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Venezuelan equine encephalitis virus (VEEV) is an alphavirus that causes disease in humans and equines eliciting both an agricultural and public health threat. In humans, the disease typically presents as a febrile illness with common signs of fever and malaise. Four to fourteen percent of Venezuelan equine encephalitis (VEE) cases are associated with severe neurological complications due to encephalitis caused by VEEV's propensity to infect the brain. Public health concerns are exacerbated by VEEV's aerosolization capabilities, low infectious dose and affordability to mass produce. These qualities drove interest in the pathogen as a bioweapon by the US and the former Soviet Union during the cold war. As a precautionary response to VEEV's notoriety as a biothreat, the National Institute of Allergies and Infectious Diseases has classified VEEV as a category B priority pathogen, and the Human Health Services and United States Department of Agriculture list live virulent strains of VEEV as a select agent and require the pathogen to be manipulated in highly regulated biosafety level 3 (BSL3) facilities. There are currently no FDA approved vaccines or antivirals to target VEEV or other closely related alphaviruses associated with clinical disease in humans. The research performed in this dissertation aimed to elucidate new antiviral targets and treatments to help bridge gaps in current understanding of alphaviruses. The current market lacks available antibodies for E1 specific isolation. In response, a recombinant VEEV TC-83 was produced with a V5 tag at the C-terminal of the E1 sequence to enable VEEV E1 detection. Sequencing was used to verify V5 insertion in the plasmid and immunoprecipitation was used to verify V5 insertion within the E1 glycoprotein. Replication kinetics experiments verified the virus replicated similarly to the parental VEEV TC-83 strain, while passaging experiments verified the tag was highly stable for up to 10 passages. This research produced a

Background: Hepatocellular carcinoma (HCC) is one of the most common primary liver tumors in humans and dogs. Excessive adrenocortical hormone exposure may cause steroid hepatopathy, which may develop into HCC. In our previous study, hyperadrenocorticism (HAC) was a highly concurrent disease in dogs with HCC. Therefore, this study hypothesized that adrenal steroid alterations might be involved in hepatocarcinogenesis and aimed to specify the relationship between HAC and HCC in dogs. Materials and methods: This study included 46 dogs brought to the Hokkaido University Veterinary Teaching Hospital between March 2019 and December 2020. Owners gave their signed consent for blood collection on their first visit. A total of 19 steroids (14 steroids and 5 metabolites) in the baseline serum of 15 dogs with HCC, 15 dogs with HAC, and 10 dogs with both diseases were quantitatively measured using the developed liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) method. Results: In each group, 11 steroids were detected higher than 50%. The detection rate of steroid hormones did not significantly differ between the groups (p > 0.05). Principle component analysis (PCA) showed that the steroid profiles of the three groups were comparable. Median steroid hormone concentrations were not significantly different between the study diseases (p > 0.05). Conclusion: The developed LC/MS/MS was useful for measuring steroid hormones. Although it was clear that HAC was concurrent in dogs with HCC, none of the serum steroids was suggested to be involved in HCC.

Background: Hepatocellular carcinoma (HCC) is one of the most common primary liver tumors in humans and dogs. Excessive adrenocortical hormone exposure may cause steroid hepatopathy, which may develop into HCC. In our previous study, hyperadrenocorticism (HAC) was a highly concurrent disease in dogs with HCC. Therefore, this study hypothesized that adrenal steroid alterations might be involved in hepatocarcinogenesis and aimed to specify the relationship between HAC and HCC in dogs. Materials and methods: This study included 46 dogs brought to the Hokkaido University Veterinary Teaching Hospital between March 2019 and December 2020. Owners gave their signed consent for blood collection on their first visit. A total of 19 steroids (14 steroids and 5 metabolites) in the baseline serum of 15 dogs with HCC, 15 dogs with HAC, and 10 dogs with both diseases were quantitatively measured using the developed liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) method. Results: In each group, 11 steroids were detected higher than 50%. The detection rate of steroid hormones did not significantly differ between the groups (p > 0.05). Principle component analysis (PCA) showed that the steroid profiles of the three groups were comparable. Median steroid hormone concentrations were not significantly different between the study diseases (p > 0.05). Conclusion: The developed LC/MS/MS was useful for measuring steroid hormones. Although it was clear that HAC was concurrent in dogs with HCC, none of the serum steroids was suggested to be involved in HCC.

Okadaic acid (OA) and its main structural analogs dinophysistoxin-1 (DTX1) and dinophysistoxin-2 (DTX2) are marine lipophilic phycotoxins distributed worldwide that can be accumulated by edible shellfish and can cause diarrheic shellfish poisoning (DSP). In order to study their toxicokinetics, mice were treated with different doses of OA, DTX1, or DTX2 and signs of toxicity were recorded up to 24 h. Toxin distribution in the main organs from the gastrointestinal tract was assessed by liquid chromatography-mass spectrometry (LC/MS/MS) analysis. Our results indicate a dose-dependency in gastrointestinal absorption of these toxins. Twenty-four hours post-administration, the highest concentration of toxin was detected in the stomach and, in descending order, in the large intestine, small intestine, and liver. There was also a different toxicokinetic pathway between OA, DTX1, and DTX2. When the same toxin doses are compared, more OA than DTX1 is detected in the small intestine. OA and DTX1 showed similar concentrations in the stomach, liver, and large intestine tissues, but the amount of DTX2 is much lower in all these organs, providing information on DSP toxicokinetics for human safety assessment

RATIONALE Glyphosate is one of the most widely used herbicides and it is suspected to affect the intestinal microbiota through inhibition of aromatic amino acid synthesis via the shikimate pathway. In vitro microbiome bioreactors are increasingly used as model systems to investigate effects on the intestinal microbiota and consequently methods for the quantitation of glyphosate and its degradation product AMPA in microbiome model systems are required. METHODSAn optimized protocol enables the analysis of both glyphosate and AMPA by simple extraction with methanol:acetonitrile:water (2:3:1) without further enrichment steps. Glyphosate and AMPA are separated by liquid chromatography on an amide column and identified and quantified with a targeted MS/MS method on a QTRAP 5500 system (AB Sciex). RESULTS Our method has a limit of detection (LOD) in extracted water samples of < 2 ng/mL for both glyphosate and AMPA. In complex intestinal medium the LOD is 2 ng/mL and 5 ng/mL for glyphosate and AMPA, respectively. These LODs allow for measurement at exposure‐relevant concentrations. Glyphosate levels in a bioreactor model of porcine colon were determined and consequently it was verified whether AMPA was produced by porcine gut microbiota. CONCLUSIONS The method presented here allows quantitation of glyphosate and AMPA in complex bioreactor fluids and thus enables studies on the impact of glyphosate and its metabolism on the intestinal microbiota. In addition, the extraction protocol is compatible with an untargeted metabolomics analysis, thus allowing other perturbations caused by glyphosate in the same sample to be looked for.

Breastfeeding is strongly encouraged for infant and maternal health. Benzodiazepines (BZDs) are widely prescribed drugs for symptoms, such as anxiety and insomnia, which many women could experience during the postpartum period. However, limited information is currently available to evaluate the transfer of different BZDs into breastmilk. In order to assess the proprieties of this medication during breastfeeding, robust and sensitive analytical methods to quantify BZDs are required. For this purpose, we developed a method for quantification of BZDs, including alprazolam, bromazepam, clonazepam, clotiazepam, etizolam, flunitrazepam, lorazepam, and CM7116 (a metabolite of ethyl loflazepate), in human breastmilk and plasma using liquid chromatography/tandem mass spectrometry (LC/MS/MS). Sample preparation was performed by a simple liquid-liquid extraction (LLE) with ethyl acetate. For sample preparation of CM7116, the pretreatment process to completely obtain the metabolite was added before the LLE step. The BZDs were separated by a C column using a gradient elution of acetonitrile in aqueous ammonium acetate solution, and were detected in the positive ion electrospray mode with multiple reaction monitoring (MRM). Lower limits of quantification (LLOQs) in breastmilk ranged from 0.25 to 0.5 ng/mL, and those in plasma ranged from 0.5 to 1.0 ng/mL. The intra-day and inter-day precision, and accuracy of data were assessed and found to be acceptable. The developed method was successfully applied to measure the concentration of alprazolam in breastmilk and plasma, which were donated by a lactating woman who had been regularly treated with alprazolam. Milk to plasma (M/P) ratios were calculated as 0.52 (before oral administration) and 0.49 (2 h after administration) 3 days after delivery. The M/P ratio 1 month after delivery was calculated as 0.41 (2 h after administration). We estimated that the relative infant dose (RID) values of alprazolam ranged from 3.11 to 4.61%.

Breastfeeding is strongly encouraged for infant and maternal health. Benzodiazepines (BZDs) are widely prescribed drugs for symptoms, such as anxiety and insomnia, which many women could experience during the postpartum period. However, limited information is currently available to evaluate the transfer of different BZDs into breastmilk. In order to assess the proprieties of this medication during breastfeeding, robust and sensitive analytical methods to quantify BZDs are required. For this purpose, we developed a method for quantification of BZDs, including alprazolam, bromazepam, clonazepam, clotiazepam, etizolam, flunitrazepam, lorazepam, and CM7116 (a metabolite of ethyl loflazepate), in human breastmilk and plasma using liquid chromatography/tandem mass spectrometry (LC/MS/MS). Sample preparation was performed by a simple liquid-liquid extraction (LLE) with ethyl acetate. For sample preparation of CM7116, the pretreatment process to completely obtain the metabolite was added before the LLE step. The BZDs were separated by a C column using a gradient elution of acetonitrile in aqueous ammonium acetate solution, and were detected in the positive ion electrospray mode with multiple reaction monitoring (MRM). Lower limits of quantification (LLOQs) in breastmilk ranged from 0.25 to 0.5 ng/mL, and those in plasma ranged from 0.5 to 1.0 ng/mL. The intra-day and inter-day precision, and accuracy of data were assessed and found to be acceptable. The developed method was successfully applied to measure the concentration of alprazolam in breastmilk and plasma, which were donated by a lactating woman who had been regularly treated with alprazolam. Milk to plasma (M/P) ratios were calculated as 0.52 (before oral administration) and 0.49 (2 h after administration) 3 days after delivery. The M/P ratio 1 month after delivery was calculated as 0.41 (2 h after administration). We estimated that the relative infant dose (RID) values of alprazolam ranged from 3.11 to 4.61%.

Striatal-enriched protein tyrosine phosphatase (STEP) is a brain-specific protein phosphatase that regulates a variety of synaptic proteins, including NMDA receptors (NAMDRs). To better understand STEP's effect on other receptors, we used mass spectrometry to identify the STEP61 interactome. We identified a number of known interactors, but also ones including the GluA2 subunit of AMPA receptors (AMPARs). We show that STEP61 binds to the C termini of GluA2 and GluA3 as well as endogenous AMPARs in hippocampus. The synaptic expression of GluA2 and GluA3 is increased in STEP-KO mouse brain, and STEP knockdown in hippocampal slices increases AMPAR-mediated synaptic currents. Interestingly, STEP61 overexpression reduces the synaptic expression and synaptic currents of both AMPARs and NMDARs. Furthermore, STEP61 regulation of synaptic AMPARs is mediated by lysosomal degradation. Thus, we report a comprehensive list of STEP61 binding partners, including AMPARs, and reveal a central role for STEP61 in differentially organizing synaptic AMPARs and NMDARs.

Breastfeeding is strongly encouraged for infant and maternal health. Benzodiazepines (BZDs) are widely prescribed drugs for symptoms, such as anxiety and insomnia, which many women could experience during the postpartum period. However, limited information is currently available to evaluate the transfer of different BZDs into breastmilk. In order to assess the proprieties of this medication during breastfeeding, robust and sensitive analytical methods to quantify BZDs are required. For this purpose, we developed a method for quantification of BZDs, including alprazolam, bromazepam, clonazepam, clotiazepam, etizolam, flunitrazepam, lorazepam, and CM7116 (a metabolite of ethyl loflazepate), in human breastmilk and plasma using liquid chromatography/tandem mass spectrometry (LC/MS/MS). Sample preparation was performed by a simple liquid-liquid extraction (LLE) with ethyl acetate. For sample preparation of CM7116, the pretreatment process to completely obtain the metabolite was added before the LLE step. The BZDs were separated by a C column using a gradient elution of acetonitrile in aqueous ammonium acetate solution, and were detected in the positive ion electrospray mode with multiple reaction monitoring (MRM). Lower limits of quantification (LLOQs) in breastmilk ranged from 0.25 to 0.5 ng/mL, and those in plasma ranged from 0.5 to 1.0 ng/mL. The intra-day and inter-day precision, and accuracy of data were assessed and found to be acceptable. The developed method was successfully applied to measure the concentration of alprazolam in breastmilk and plasma, which were donated by a lactating woman who had been regularly treated with alprazolam. Milk to plasma (M/P) ratios were calculated as 0.52 (before oral administration) and 0.49 (2 h after administration) 3 days after delivery. The M/P ratio 1 month after delivery was calculated as 0.41 (2 h after administration). We estimated that the relative infant dose (RID) values of alprazolam ranged from 3.11 to 4.61%.

La DCE a défini des Normes de Qualité Environnementale (NQE) pour les substances identifiées comme prioritaires. Parmi les substances ciblées, le dichlorvos, insecticide acaricide aujourd’hui interdit en France pose un challenge analytique car sa NQE est très faible (NQEeau douce : 0,6 ng/L, NQE eau marine : 0,06 ng/L, ce qui implique de pouvoir atteindre une limite de quantification (LQ) de 0,02 ng/L selon la directive QA/QC (2009/90/CE). L’objectif principal de ce travail est d’atteindre la limite de quantification visée (0,02 ng/L) à travers l’amélioration des techniques d’échantillonnage, d’extraction et d’analyse du dichlorvos. L’analyse est faite en chromatographie en phase liquide. Le mode d’acquisition qui a été choisi pour le développement de la quantification du dichlorvos par spectrométrie de masse en tandem est le mode MRM (Multiple Reaction Monitor). Le type de source utilisée est une source à ionisation par électronébuliseur (ESI : electrospray ionization source) en mode positif. En parallèle de l’amélioration de la méthodologie analytique, un travail particulier a été mené sur la calibration afin d’obtenir un taux d’échantillonnage pour le dichlorvos et le protocole d’extraction des échantillonneurs passifs de type POCIS (Polar Organic Chemical Integrative Sampler) a également été optimisé. Les développements réalisés (LC/MS/MS couplé aux capacités de concentration des échantillonneurs passifs de type POCIS) ont permis d’abaisser la limite de quantification du dichlorvos à 0,9 pg/L (ou 0,0009 ng/L) pour une durée d’exposition de 15 jours. Ces performances analytiques obtenues sont compatibles avec le suivi du dichlorvos selon les performances demandées par les directives Cadre sur l’Eau (DCE) (2000/60/EC) et directive QA/QC (2009/90/CE).

La DCE a défini des Normes de Qualité Environnementale (NQE) pour les substances identifiées comme prioritaires. Parmi les substances ciblées, le dichlorvos, insecticide acaricide aujourd’hui interdit en France pose un challenge analytique car sa NQE est très faible (NQEeau douce : 0,6 ng/L, NQE eau marine : 0,06 ng/L, ce qui implique de pouvoir atteindre une limite de quantification (LQ) de 0,02 ng/L selon la directive QA/QC (2009/90/CE). L’objectif principal de ce travail est d’atteindre la limite de quantification visée (0,02 ng/L) à travers l’amélioration des techniques d’échantillonnage, d’extraction et d’analyse du dichlorvos. L’analyse est faite en chromatographie en phase liquide. Le mode d’acquisition qui a été choisi pour le développement de la quantification du dichlorvos par spectrométrie de masse en tandem est le mode MRM (Multiple Reaction Monitor). Le type de source utilisée est une source à ionisation par électronébuliseur (ESI : electrospray ionization source) en mode positif. En parallèle de l’amélioration de la méthodologie analytique, un travail particulier a été mené sur la calibration afin d’obtenir un taux d’échantillonnage pour le dichlorvos et le protocole d’extraction des échantillonneurs passifs de type POCIS (Polar Organic Chemical Integrative Sampler) a également été optimisé. Les développements réalisés (LC/MS/MS couplé aux capacités de concentration des échantillonneurs passifs de type POCIS) ont permis d’abaisser la limite de quantification du dichlorvos à 0,9 pg/L (ou 0,0009 ng/L) pour une durée d’exposition de 15 jours. Ces performances analytiques obtenues sont compatibles avec le suivi du dichlorvos selon les performances demandées par les directives Cadre sur l’Eau (DCE) (2000/60/EC) et directive QA/QC (2009/90/CE).

В работе выявлены возможности одновременного определения четырех противотуберкулезных препаратов (ПТП) ( этамбутол, пиразинамид, изониазид, рифампицин ) методами обращённо-фазовой ВЭЖХ (ОФ ВЭЖХ) и ион-парной хроматографии. Предложен вариант одновременного определения этих ПТП в плазме крови человека методом ОФ ВЭЖХ с тандемным масс-спектрометрическим детектированием с электроспрей ионизацией. Детектирование осуществляли в режиме положительной ионизации путём мониторинга множественных реакций (MRM). Оптимизированы условия фрагментации для каждого лекарственного вещества. Найдены условия подготовки плазмы крови к ВЭЖХ/МС анализу, включающие осаждение белков плазмы крови ацетонитрилом. Значения степеней извлечения ПТП составили 85-90 %. Проведена оценка влияния матрицы пробы на разделение и ионизацию ПТП методом пост-экстракционной добавки. Показано, что разбавление экстракта плазмы крови в 10 раз достаточно для требуемого снижения матричного эффекта. Изучена стабильность ПТП в процессе анализа (автосамплер 1 и 12 ч.) и в условиях хранения (3 цикла заморозка-разморозка). Предложен способ увеличения стабильности рифампицина с добавлением в качестве антиоксиданта аскорбиновой кислоты (1 мг/мл). Пределы обнаружения с УФ детектированием составили от 2 до 20 мкг/мл, с МС детектированием в SIM-режиме от 2 до 15 нг/мл и в MRM-режиме от 0.5 до 10 нг/мл. В оптимизированных условиях показана возможность обнаружения и количественного определения всех четырех ПТП в плазме крови больного туберкулезом с проводимой лекарственной терапией., In the current study the possibility of the simultaneous determination of anti-tuberculosis (anti-TB) drugs (isoniazid, pyrazinamide, ethambutol and rifampicin) using the reversed-phase HPLC (RP-HPLC) and ion-pair chromatography was investigated. A selective and highly sensitive liquid chromatography/tandem mass spectrometry method for the simultaneous determination of four anti-TB drugs (isoniazid, pyrazinamide, ethambutol and rifampicin) in the human plasma was developed. The detection was carried out using the multiple reaction-monitoring (MRM) modes with positive polarity. The fragmentation conditions for each drug were optimized, and the conditions for the blood plasma preparation for HPLC/MS analysis, including the protein precipitation with ACN with a ratio of 3:1 (by volume), were chosen. The matrix effects on the separation and ionization of anti-TB drugs were estimated by the post-extraction additives method. It was shown that the 10-fold dilution of plasma extracts was sufficient to decrease the influence of the sample matrix. The stability of anti-TB drugs during the analysis (in autosampler at 1 and 12 hours) and at storage conditions (3 cycles of freeze-thaw) was studied. The method for increasing the stability of rifampicin using ascorbic acid (1 mg/ml) as antioxidant was provided. The LOD with UV detection were 2 - 20 µg/ml, in SIM-mode - 2 - 15 ng/ml and in MRM-mode - 0.5 - 10 ng/ml respectively. The possibility of the determination of four anti-TB drugs in real plasma samples of patients with tuberculosis undergoing drug therapy in optimized conditions HPLC/MC was shown.

Humans are exposed to electrophilically reactive compounds, both formed endogenously and from exogenous exposure. Such compounds could react and form stable reaction products, adducts, at nucleophilic sites in proteins and DNA. The formation of adducts constitutes a risk for effects, such as cancer and contact allergy, and plays a role in ageing processes. Adducts to proteins offer a possibility to measure electrophilic compounds in vivo. Adductomic approaches aim to study the totality of adducts, to specific biomolecules, by mass spectrometric screening. This thesis describes the development and application of an adductomic approach for the screening of unknown adducts to N-terminal valine (Val) in hemoglobin (Hb) by liquid chromatography tandem mass spectrometry (LC/MS/MS). The adductomic approach is based on the FIRE procedure, a modified Edman procedure for the analysis of adducts to N-terminal Val in Hb by LC/MS/MS. The adduct screening was performed by stepwise scanning of precursor ions in small mass increments and monitoring four fragments common for derivatives of detached Val adducts, in the multiple reaction monitoring mode. Samples from 12 smokers/nonsmokers were screened with the adductomic approach, and seven previously identified adducts and 19 unknown adducts were detected. A semiquantitative approach was applied for approximate quantification of adduct levels. A strategy for identifying unknown Hb adducts using adductome LC/MS/MS data was formulated and applied for the identification of unknown adducts. Identifications were based on the observed m/z of precursor ions and retention times combined with databases and Log P calculations. Hypothesized adducts were generated in vitro for comparison and matching with the corresponding unknown adducts. Five identified adducts correspond to the precursor electrophiles ethyl vinyl ketone (EVK), glyoxal, methylglyoxal, acrylic acid, and 1-octen-3-one. These adducts, except the adducts corresponding to glyoxal, At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.

Humans are exposed to electrophilically reactive compounds, both formed endogenously and from exogenous exposure. Such compounds could react and form stable reaction products, adducts, at nucleophilic sites in proteins and DNA. The formation of adducts constitutes a risk for effects, such as cancer and contact allergy, and plays a role in ageing processes. Adducts to proteins offer a possibility to measure electrophilic compounds in vivo. Adductomic approaches aim to study the totality of adducts, to specific biomolecules, by mass spectrometric screening. This thesis describes the development and application of an adductomic approach for the screening of unknown adducts to N-terminal valine (Val) in hemoglobin (Hb) by liquid chromatography tandem mass spectrometry (LC/MS/MS). The adductomic approach is based on the FIRE procedure, a modified Edman procedure for the analysis of adducts to N-terminal Val in Hb by LC/MS/MS. The adduct screening was performed by stepwise scanning of precursor ions in small mass increments and monitoring four fragments common for derivatives of detached Val adducts, in the multiple reaction monitoring mode. Samples from 12 smokers/nonsmokers were screened with the adductomic approach, and seven previously identified adducts and 19 unknown adducts were detected. A semiquantitative approach was applied for approximate quantification of adduct levels. A strategy for identifying unknown Hb adducts using adductome LC/MS/MS data was formulated and applied for the identification of unknown adducts. Identifications were based on the observed m/z of precursor ions and retention times combined with databases and Log P calculations. Hypothesized adducts were generated in vitro for comparison and matching with the corresponding unknown adducts. Five identified adducts correspond to the precursor electrophiles ethyl vinyl ketone (EVK), glyoxal, methylglyoxal, acrylic acid, and 1-octen-3-one. These adducts, except the adducts corresponding to glyoxal, At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.

Humans are exposed to electrophilically reactive compounds, both formed endogenously and from exogenous exposure. Such compounds could react and form stable reaction products, adducts, at nucleophilic sites in proteins and DNA. The formation of adducts constitutes a risk for effects, such as cancer and contact allergy, and plays a role in ageing processes. Adducts to proteins offer a possibility to measure electrophilic compounds in vivo. Adductomic approaches aim to study the totality of adducts, to specific biomolecules, by mass spectrometric screening. This thesis describes the development and application of an adductomic approach for the screening of unknown adducts to N-terminal valine (Val) in hemoglobin (Hb) by liquid chromatography tandem mass spectrometry (LC/MS/MS). The adductomic approach is based on the FIRE procedure, a modified Edman procedure for the analysis of adducts to N-terminal Val in Hb by LC/MS/MS. The adduct screening was performed by stepwise scanning of precursor ions in small mass increments and monitoring four fragments common for derivatives of detached Val adducts, in the multiple reaction monitoring mode. Samples from 12 smokers/nonsmokers were screened with the adductomic approach, and seven previously identified adducts and 19 unknown adducts were detected. A semiquantitative approach was applied for approximate quantification of adduct levels. A strategy for identifying unknown Hb adducts using adductome LC/MS/MS data was formulated and applied for the identification of unknown adducts. Identifications were based on the observed m/z of precursor ions and retention times combined with databases and Log P calculations. Hypothesized adducts were generated in vitro for comparison and matching with the corresponding unknown adducts. Five identified adducts correspond to the precursor electrophiles ethyl vinyl ketone (EVK), glyoxal, methylglyoxal, acrylic acid, and 1-octen-3-one. These adducts, except the adducts corresponding to glyoxal, At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.

Humans are exposed to electrophilically reactive compounds, both formed endogenously and from exogenous exposure. Such compounds could react and form stable reaction products, adducts, at nucleophilic sites in proteins and DNA. The formation of adducts constitutes a risk for effects, such as cancer and contact allergy, and plays a role in ageing processes. Adducts to proteins offer a possibility to measure electrophilic compounds in vivo. Adductomic approaches aim to study the totality of adducts, to specific biomolecules, by mass spectrometric screening. This thesis describes the development and application of an adductomic approach for the screening of unknown adducts to N-terminal valine (Val) in hemoglobin (Hb) by liquid chromatography tandem mass spectrometry (LC/MS/MS). The adductomic approach is based on the FIRE procedure, a modified Edman procedure for the analysis of adducts to N-terminal Val in Hb by LC/MS/MS. The adduct screening was performed by stepwise scanning of precursor ions in small mass increments and monitoring four fragments common for derivatives of detached Val adducts, in the multiple reaction monitoring mode. Samples from 12 smokers/nonsmokers were screened with the adductomic approach, and seven previously identified adducts and 19 unknown adducts were detected. A semiquantitative approach was applied for approximate quantification of adduct levels. A strategy for identifying unknown Hb adducts using adductome LC/MS/MS data was formulated and applied for the identification of unknown adducts. Identifications were based on the observed m/z of precursor ions and retention times combined with databases and Log P calculations. Hypothesized adducts were generated in vitro for comparison and matching with the corresponding unknown adducts. Five identified adducts correspond to the precursor electrophiles ethyl vinyl ketone (EVK), glyoxal, methylglyoxal, acrylic acid, and 1-octen-3-one. These adducts, except the adducts corresponding to glyoxal, At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.

Humans are exposed to electrophilically reactive compounds, both formed endogenously and from exogenous exposure. Such compounds could react and form stable reaction products, adducts, at nucleophilic sites in proteins and DNA. The formation of adducts constitutes a risk for effects, such as cancer and contact allergy, and plays a role in ageing processes. Adducts to proteins offer a possibility to measure electrophilic compounds in vivo. Adductomic approaches aim to study the totality of adducts, to specific biomolecules, by mass spectrometric screening. This thesis describes the development and application of an adductomic approach for the screening of unknown adducts to N-terminal valine (Val) in hemoglobin (Hb) by liquid chromatography tandem mass spectrometry (LC/MS/MS). The adductomic approach is based on the FIRE procedure, a modified Edman procedure for the analysis of adducts to N-terminal Val in Hb by LC/MS/MS. The adduct screening was performed by stepwise scanning of precursor ions in small mass increments and monitoring four fragments common for derivatives of detached Val adducts, in the multiple reaction monitoring mode. Samples from 12 smokers/nonsmokers were screened with the adductomic approach, and seven previously identified adducts and 19 unknown adducts were detected. A semiquantitative approach was applied for approximate quantification of adduct levels. A strategy for identifying unknown Hb adducts using adductome LC/MS/MS data was formulated and applied for the identification of unknown adducts. Identifications were based on the observed m/z of precursor ions and retention times combined with databases and Log P calculations. Hypothesized adducts were generated in vitro for comparison and matching with the corresponding unknown adducts. Five identified adducts correspond to the precursor electrophiles ethyl vinyl ketone (EVK), glyoxal, methylglyoxal, acrylic acid, and 1-octen-3-one. These adducts, except the adducts corresponding to glyoxal, At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.

Humans are exposed to electrophilically reactive compounds, both formed endogenously and from exogenous exposure. Such compounds could react and form stable reaction products, adducts, at nucleophilic sites in proteins and DNA. The formation of adducts constitutes a risk for effects, such as cancer and contact allergy, and plays a role in ageing processes. Adducts to proteins offer a possibility to measure electrophilic compounds in vivo. Adductomic approaches aim to study the totality of adducts, to specific biomolecules, by mass spectrometric screening. This thesis describes the development and application of an adductomic approach for the screening of unknown adducts to N-terminal valine (Val) in hemoglobin (Hb) by liquid chromatography tandem mass spectrometry (LC/MS/MS). The adductomic approach is based on the FIRE procedure, a modified Edman procedure for the analysis of adducts to N-terminal Val in Hb by LC/MS/MS. The adduct screening was performed by stepwise scanning of precursor ions in small mass increments and monitoring four fragments common for derivatives of detached Val adducts, in the multiple reaction monitoring mode. Samples from 12 smokers/nonsmokers were screened with the adductomic approach, and seven previously identified adducts and 19 unknown adducts were detected. A semiquantitative approach was applied for approximate quantification of adduct levels. A strategy for identifying unknown Hb adducts using adductome LC/MS/MS data was formulated and applied for the identification of unknown adducts. Identifications were based on the observed m/z of precursor ions and retention times combined with databases and Log P calculations. Hypothesized adducts were generated in vitro for comparison and matching with the corresponding unknown adducts. Five identified adducts correspond to the precursor electrophiles ethyl vinyl ketone (EVK), glyoxal, methylglyoxal, acrylic acid, and 1-octen-3-one. These adducts, except the adducts corresponding to glyoxal, At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.

Zolpidem is a nonbenzodiazepine sedative hypnotic drug used for the short-term treatment of insomnia. Its use is common and wide-spread. While quite effective in producing sedation, zolpidem has potentially hazardous side effects when put in the context of complex tasks. Side effects include drowsiness, dizziness, amnesia, nausea, double vision, diminished reflexes, and a lack of coordination. Due to its potentially deleterious effects on aviation safety, it is important for our laboratory to more fully understand its postmortem concentrations and distribution. Therefore, our laboratory has developed a sensitive method to identify and quantitate zolpidem in biological specimens. Furthermore, we have evaluated the distribution of this compound in various postmortem tissues and fluids from 10 fatal aviation accident cases. Each of these cases had a majority of the desired biological tissues and fluids available for analysis (blood, urine, vitreous humor, liver, lung, kidney, spleen, muscle, heart, and brain). This method incorporated a modified acetonitrile crash and shoot extraction and a Waters Xevo TQ-S (MS/MS) with an Acquity UPLC. The linear dynamic range was 0.39 - 800 ng/mL. The extraction efficiencies ranged from 78 - 87%, depending on concentration. Postmortem blood zolpidem concentrations in these 10 cases ranged from 8 - 77 ng/mL. The highest concentrations of zolpidem present in each victim were found in the liver, spleen, lung, and kidney tissues. Distribution coefficients for zolpidem were determined for each of the specimen types analyzed. These coefficients are expressed relative to the blood concentration in each case. This method proved to be simple, accurate, and robust for the identification and quantitation of zolpidem in postmortem fluids and tissues., The original document contains color images.

U ovoj doktorskoj disertaciji prikazani su rezultati istraživanja 15 vrsta biljaka koje pripadaju rodovima Rumex, Polygonum, Bistorta, Persicaria i Fagopyrum, podfamilije Polygonoideae, familije Polygonaceae, sakupljenih na teritoriji centralnog i zapadnog Balkana u periodu od 2009-2011. godine. Sprovedena istraživanja su se odvijala u dva pravca: fitohemijska i biohemijsko-biološka ispitivanja. Predmet analiza bili su ekstrakti herbi i rizoma ispitivanih biljaka. Fitohemijska ispitivanja obuhvatila su, pored spektrofotometrijskog određivanja ukupnih fenola, ukupnih flavonoida i ukupnih antrahinonskih jedinjenja, i određivanje sadržaja 51 komponente iz standardne smeše različitih klasa fenolnih jedinjenja LC-MSMS metodom, odnosno hromatografsko profilisanje ekstrakata LC-DAD-MS metodom. Odabirom nekoliko različitih model sistema za merenje antioksidantne aktivnosti (neutralizacija DPPH radikala, redoks kapacitet - FRAP test, skevindžer aktivnost prema superoksidanjon radikalu, NO radikalu i OH radikalu, kao i inhibicija lipidne peroksidacije) procenjen je antioksidantni potencijal ekstrakata, dok je za procenu njihove antiinflamatorne aktivnosti korišćen potencijal inhibicije biosinteze medijatora inflamacije u humanim trombocitima (kao model sistemu). Mikrobiološka ispitivanja su obuhvatila određivanje potencijala ovih vrsta u inhibiciji rasta serije gram pozitivnih i gram negativnih sojeva batkerija. Konačno, urađena je analiza korelacije hemijskog sastava, biološke aktivnosti i pripadnosti taksonomskim grupama., Phytochemical and biochemical analysis of herbal and root ethanol extracts of 15 species belonging to different genera (Rumex, Polygonum, Bistorta, Persicaria and Fagopyrum) of subfamily Polygonoideae, was examined. Phytochemical characterization included spectrophotometric determination of total phenolic, total flavonoids and total anthraquinone contents, quantification of 51 secondary metabolites by LC/MS/MS analysis and chromatographic fingerprinting by LC/DAD/MS technique, of prepared extracts. The antioxidant activity was evaluated by measuring ferric reducing ability (FRAP) of the extracts and their radical scavenging capacity towards DPPH, OH, NO and O2– radicals, and inhibition of lipid peroxidation). Antiinflammatory activity was evaluated by LC/MS/MS monitoring of selected metabolites (12-(S)-HHT, 12(S)-HETE, PGE2 , PGF2α, and TXB2) formed in cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism. Human platelets were used as a source of enzymes, while inflammation was induced by calcimycin. The antibacterial activity of prepared extracts against nine bacterial strains was evaluated by microtiter assay with resazurin as a colorimetric growth indicator.

For the first time, dried saliva spot (DSS) was used as a sampling technique for saliva samples. In the DSS technique 50 L of saliva was collected on filter paper and the saliva was then extracted with an organic solvent. The local anesthetic lidocaine was used as a model compound, which was determined in the DSS using liquid chromatography and mass spectrometry. The results obtained for the determination of lidocaine in saliva using DSS were compared with those from a previous study using a microextraction by packed sorbent syringe as the sampling method for saliva. This study shows that DSS can be used for the analysis of saliva samples. The method is promising and very easy in terms of sampling and extraction procedures. The results from this study are in good agreement with those from our previous work on the determination of lidocaine in saliva. DSS can open a new dimension in the saliva handling process in terms of sampling, storing and transport., AuthorCount:2

U ovoj doktorskoj disertaciji prikazani su rezultati istraživanja 15 vrsta biljaka koje pripadaju rodovima Rumex, Polygonum, Bistorta, Persicaria i Fagopyrum, podfamilije Polygonoideae, familije Polygonaceae, sakupljenih na teritoriji centralnog i zapadnog Balkana u periodu od 2009-2011. godine. Sprovedena istraživanja su se odvijala u dva pravca: fitohemijska i biohemijsko-biološka ispitivanja. Predmet analiza bili su ekstrakti herbi i rizoma ispitivanih biljaka. Fitohemijska ispitivanja obuhvatila su, pored spektrofotometrijskog određivanja ukupnih fenola, ukupnih flavonoida i ukupnih antrahinonskih jedinjenja, i određivanje sadržaja 51 komponente iz standardne smeše različitih klasa fenolnih jedinjenja LC-MSMS metodom, odnosno hromatografsko profilisanje ekstrakata LC-DAD-MS metodom. Odabirom nekoliko različitih model sistema za merenje antioksidantne aktivnosti (neutralizacija DPPH radikala, redoks kapacitet - FRAP test, skevindžer aktivnost prema superoksidanjon radikalu, NO radikalu i OH radikalu, kao i inhibicija lipidne peroksidacije) procenjen je antioksidantni potencijal ekstrakata, dok je za procenu njihove antiinflamatorne aktivnosti korišćen potencijal inhibicije biosinteze medijatora inflamacije u humanim trombocitima (kao model sistemu). Mikrobiološka ispitivanja su obuhvatila određivanje potencijala ovih vrsta u inhibiciji rasta serije gram pozitivnih i gram negativnih sojeva batkerija. Konačno, urađena je analiza korelacije hemijskog sastava, biološke aktivnosti i pripadnosti taksonomskim grupama., Phytochemical and biochemical analysis of herbal and root ethanol extracts of 15 species belonging to different genera (Rumex, Polygonum, Bistorta, Persicaria and Fagopyrum) of subfamily Polygonoideae, was examined. Phytochemical characterization included spectrophotometric determination of total phenolic, total flavonoids and total anthraquinone contents, quantification of 51 secondary metabolites by LC/MS/MS analysis and chromatographic fingerprinting by LC/DAD/MS technique, of prepared extracts. The antioxidant activity was evaluated by measuring ferric reducing ability (FRAP) of the extracts and their radical scavenging capacity towards DPPH, OH, NO and O2– radicals, and inhibition of lipid peroxidation). Antiinflammatory activity was evaluated by LC/MS/MS monitoring of selected metabolites (12-(S)-HHT, 12(S)-HETE, PGE2 , PGF2α, and TXB2) formed in cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism. Human platelets were used as a source of enzymes, while inflammation was induced by calcimycin. The antibacterial activity of prepared extracts against nine bacterial strains was evaluated by microtiter assay with resazurin as a colorimetric growth indicator.

Prostanoids and PGE2 in particular have been long viewed as one of the major mediators of inflammation in arthritis. However, experimental data indicate that PGE2 can serve both pro- and anti-inflammatory functions. We have previously shown (Kojima et al., J. Immunol. 180 (2008) 8361-8368) that microsomal prostaglandin E synthase-1 (mPGES-1) deletion, which regulates PGE2 production, resulted in the suppression of collagen-induced arthritis (CIA) in mice. This suppression was attributable, at least in part, to the impaired generation of type II collagen autoantibodies. In order to examine the function of mPGES-1 and PGE2 in a non-autoimmune form of arthritis, we used the collagen antibody-induced arthritis (CAIA) model in mice deficient in mPGES-1, thereby bypassing the engagement of the adaptive immune response in arthritis development. Here we report that mPGES-1 deletion significantly increased CAIA disease severity. The latter was associated with a significant (~3.6) upregulation of neutrophil, but not macrophage, recruitment to the inflamed joints. The lipidomic analysis of the arthritic mouse paws by quantitative liquid chromatography/tandem mass-spectrometry (LC/MS/MS) revealed a dramatic (~59-fold) reduction of PGE2 at the peak of arthritis. Altogether, this study highlights mPGES-1 and its product PGE2 as important negative regulators of neutrophil-mediated inflammation and suggests that specific mPGES-1 inhibitors may have differential effects on different types of inflammation. Furthermore, neutrophil-mediated diseases could be exacerbated by inhibition of mPGES-1.

Vzhledek k rostoucí populaci ve světě, je důležité neustále zvyšovat zemědělskou produkci, jež s sebou přináší i vyšší nároky na kvalitu. K dosažení tohoto cíle je zapotřebí nejen organických hnojiv, ale též pesticidů, tedy látek působící proti biologickým škůdcům a plísním. Bohužel tyto látky často představují velkou zátěž pro životní prostředí včetně lidského zdraví. Z toho důvodu je zapotřebí kontroly a regulace jejich užívání. Cílem této práce bylo pro vybrané pesticidy vyvinout rychlou a nenáročnou extrakční metodu pro jejich stanovení ve vzorcích půdy. Jako citlivá analytická metoda byla použita technika LC/MS/MS., Since the population in the world has been constantly increasing, the rise in the crop production is needed as well. The increase in production demands higher quality too. To achieve the goal of making an agrarian production higher, it is necessary to use organic fertilisers as well as pesticides, to protect the crop against plant pests and fungal diseases. Unfortunately, these chemical substances are not always enviromentally-friendly and have an impact to human health as well. The aim of this diploma thesis was to develop a fast and easy extraction procedure for determination of chosen pesticides from soil. LC/MS/MS was used as the sensitive analytical technique. As the result of being ecologically unsound, the pesticides must always undergo many strict inspections and regulations., Katedra analytické chemie, Dimplomantka seznámila členy komise s tématem své diplomové práce, úspěšně zodpověděla dotazy členů komise, vyslechla posudek vedoucího diplomové práce a oponenta diplomové práce a úspěšně odpověděla dotazy oponenta diplomové práce. Dotazy: 1. prof. Ing. Komers - jakého řádu jsou presentované závisloti? 2. Ing. Česla - jaké jednotky jsou uvedeny v presentovaných chromatogramech?

A LLE-GC-MS method was developed to detect PPCPs in surface water samples from Big Cypress National Park, Everglades National Park and Biscayne National Park in South Florida. The most frequently found PPCPs were caffeine, DEET and triclosan with detected maximum concentration of 169 ng/L, 27.9 ng/L and 10.9 ng/L, respectively. The detection frequencies of hormones were less than PPCPs. Detected maximal concentrations of estrone, 17β-estradiol, coprostan-3-ol, coprostane and coprostan-3-one were 5.98 ng/L, 3.34 ng/L, 16.5 ng/L, 13.5 ng/L and 6.79 ng/L, respectively. An ASE-SPE-GC-MS method was developed and applied to the analysis of the sediment and soil area where reclaimed water was used for irrigation. Most analytes were below detection limits, even though some of analytes were detected in the reclaimed water at relatively high concentrations corroborating the fact that PPCPs do not significantly partition to mineral phases. An online SPE-HPLC-APPI-MS/MS method and an online SPE-HPLC-HESI-MS/MS method were developed to analyze reclaimed water and drinking water samples. In the reclaimed water study, reclaimed water samples were collected from the sprinkler for a year-long period at Florida International University Biscayne Bay Campus, where reclaimed water was reused for irrigation. Analysis results showed that several analytes were continuously detected in all reclaimed water samples. Coprostanol, bisphenol A and DEET’s maximum concentration exceeded 10 µg/L (ppb). The four most frequently detected compounds were diphenhydramine (100%), DEET (98%), atenolol (98%) and carbamazepine (96%). In the study of drinking water, 54 tap water samples were collected from the Miami-Dade area. The maximum concentrations of salicylic acid, ibuprofen and DEET were 521 ng/L, 301 ng/L and 290 ng/L, respectively. The three most frequently detected compounds were DEET (93%), carbamazepine (43%) and salicylic acid (37%), respectively. Because the source of drinking water in Miami-D

Primary marine aerosol particles containing biogenic polymer microgels play a potential role for cloud formation in the pristine high Arctic summer. One of the major sources of the polymer gels in Arctic aerosol was suggested to be the surface water and more specifically, the surface microlayer (SML) of the open leads within the perennial sea ice as a result of bubble bursting at the air-sea interface. Phytoplankton and/or ice algae are believed to be the main origins of the polymer gels. In this thesis, we examine the chemical composition of biogenic polymers, with focus on polysaccharides, in seawater and airborne aerosol particles collected during the Arctic Summer Cloud Ocean Study (ASCOS) in the summer of 2008. The main results and findings include: A novel method using liquid chromatography coupling with tandem mass spectrometry was developed and applied for identification and quantification of polysaccharides. The enrichment of polysaccharides in the SML was shown to be a common feature of the Arctic open leads. Rising bubbles and surface coagulation of polymers are the likely mechanism for the accumulation of polysaccharides at the SML. The size dependencies of airborne polysaccharides on the travel-time since the last contact with the open sea are indicative of a submicron microgel source within the pack ice. The similarity of polysaccharides composition observed between the ambient aerosol particles and those generated by in situ bubbling experiments confines the microgel source to the open leads. The demonstrated occurrence of polysaccharides in surface sea waters and in air, with surface-active and hygroscopic properties, has shown their potential to serve as cloud condensation nuclei and subsequently promote cloud-drop activation in the pristine high Arctic. Presumably this possibility may renew interest in the complex but fascinating interactions between marine biology, aerosol, clouds and climate., At the time of doctoral defence, the following paper was unpublished and had a status as follows: Paper 4: Manuscript

Primary marine aerosol particles containing biogenic polymer microgels play a potential role for cloud formation in the pristine high Arctic summer. One of the major sources of the polymer gels in Arctic aerosol was suggested to be the surface water and more specifically, the surface microlayer (SML) of the open leads within the perennial sea ice as a result of bubble bursting at the air-sea interface. Phytoplankton and/or ice algae are believed to be the main origins of the polymer gels. In this thesis, we examine the chemical composition of biogenic polymers, with focus on polysaccharides, in seawater and airborne aerosol particles collected during the Arctic Summer Cloud Ocean Study (ASCOS) in the summer of 2008. The main results and findings include: A novel method using liquid chromatography coupling with tandem mass spectrometry was developed and applied for identification and quantification of polysaccharides. The enrichment of polysaccharides in the SML was shown to be a common feature of the Arctic open leads. Rising bubbles and surface coagulation of polymers are the likely mechanism for the accumulation of polysaccharides at the SML. The size dependencies of airborne polysaccharides on the travel-time since the last contact with the open sea are indicative of a submicron microgel source within the pack ice. The similarity of polysaccharides composition observed between the ambient aerosol particles and those generated by in situ bubbling experiments confines the microgel source to the open leads. The demonstrated occurrence of polysaccharides in surface sea waters and in air, with surface-active and hygroscopic properties, has shown their potential to serve as cloud condensation nuclei and subsequently promote cloud-drop activation in the pristine high Arctic. Presumably this possibility may renew interest in the complex but fascinating interactions between marine biology, aerosol, clouds and climate., At the time of doctoral defence, the following paper was unpublished and had a status as follows: Paper 4: Manuscript

Primary marine aerosol particles containing biogenic polymer microgels play a potential role for cloud formation in the pristine high Arctic summer. One of the major sources of the polymer gels in Arctic aerosol was suggested to be the surface water and more specifically, the surface microlayer (SML) of the open leads within the perennial sea ice as a result of bubble bursting at the air-sea interface. Phytoplankton and/or ice algae are believed to be the main origins of the polymer gels. In this thesis, we examine the chemical composition of biogenic polymers, with focus on polysaccharides, in seawater and airborne aerosol particles collected during the Arctic Summer Cloud Ocean Study (ASCOS) in the summer of 2008. The main results and findings include: A novel method using liquid chromatography coupling with tandem mass spectrometry was developed and applied for identification and quantification of polysaccharides. The enrichment of polysaccharides in the SML was shown to be a common feature of the Arctic open leads. Rising bubbles and surface coagulation of polymers are the likely mechanism for the accumulation of polysaccharides at the SML. The size dependencies of airborne polysaccharides on the travel-time since the last contact with the open sea are indicative of a submicron microgel source within the pack ice. The similarity of polysaccharides composition observed between the ambient aerosol particles and those generated by in situ bubbling experiments confines the microgel source to the open leads. The demonstrated occurrence of polysaccharides in surface sea waters and in air, with surface-active and hygroscopic properties, has shown their potential to serve as cloud condensation nuclei and subsequently promote cloud-drop activation in the pristine high Arctic. Presumably this possibility may renew interest in the complex but fascinating interactions between marine biology, aerosol, clouds and climate., At the time of doctoral defence, the following paper was unpublished and had a status as follows: Paper 4: Manuscript

Primary marine aerosol particles containing biogenic polymer microgels play a potential role for cloud formation in the pristine high Arctic summer. One of the major sources of the polymer gels in Arctic aerosol was suggested to be the surface water and more specifically, the surface microlayer (SML) of the open leads within the perennial sea ice as a result of bubble bursting at the air-sea interface. Phytoplankton and/or ice algae are believed to be the main origins of the polymer gels. In this thesis, we examine the chemical composition of biogenic polymers, with focus on polysaccharides, in seawater and airborne aerosol particles collected during the Arctic Summer Cloud Ocean Study (ASCOS) in the summer of 2008. The main results and findings include: A novel method using liquid chromatography coupling with tandem mass spectrometry was developed and applied for identification and quantification of polysaccharides. The enrichment of polysaccharides in the SML was shown to be a common feature of the Arctic open leads. Rising bubbles and surface coagulation of polymers are the likely mechanism for the accumulation of polysaccharides at the SML. The size dependencies of airborne polysaccharides on the travel-time since the last contact with the open sea are indicative of a submicron microgel source within the pack ice. The similarity of polysaccharides composition observed between the ambient aerosol particles and those generated by in situ bubbling experiments confines the microgel source to the open leads. The demonstrated occurrence of polysaccharides in surface sea waters and in air, with surface-active and hygroscopic properties, has shown their potential to serve as cloud condensation nuclei and subsequently promote cloud-drop activation in the pristine high Arctic. Presumably this possibility may renew interest in the complex but fascinating interactions between marine biology, aerosol, clouds and climate., At the time of doctoral defence, the following paper was unpublished and had a status as follows: Paper 4: Manuscript

Primary marine aerosol particles containing biogenic polymer microgels play a potential role for cloud formation in the pristine high Arctic summer. One of the major sources of the polymer gels in Arctic aerosol was suggested to be the surface water and more specifically, the surface microlayer (SML) of the open leads within the perennial sea ice as a result of bubble bursting at the air-sea interface. Phytoplankton and/or ice algae are believed to be the main origins of the polymer gels. In this thesis, we examine the chemical composition of biogenic polymers, with focus on polysaccharides, in seawater and airborne aerosol particles collected during the Arctic Summer Cloud Ocean Study (ASCOS) in the summer of 2008. The main results and findings include: A novel method using liquid chromatography coupling with tandem mass spectrometry was developed and applied for identification and quantification of polysaccharides. The enrichment of polysaccharides in the SML was shown to be a common feature of the Arctic open leads. Rising bubbles and surface coagulation of polymers are the likely mechanism for the accumulation of polysaccharides at the SML. The size dependencies of airborne polysaccharides on the travel-time since the last contact with the open sea are indicative of a submicron microgel source within the pack ice. The similarity of polysaccharides composition observed between the ambient aerosol particles and those generated by in situ bubbling experiments confines the microgel source to the open leads. The demonstrated occurrence of polysaccharides in surface sea waters and in air, with surface-active and hygroscopic properties, has shown their potential to serve as cloud condensation nuclei and subsequently promote cloud-drop activation in the pristine high Arctic. Presumably this possibility may renew interest in the complex but fascinating interactions between marine biology, aerosol, clouds and climate., At the time of doctoral defence, the following paper was unpublished and had a status as follows: Paper 4: Manuscript

Prostanoids are bioactive substances that contribute to various biological and pathological processes. To evaluate both extracellular and intracellular levels of prostanoids at the same time, we developed methods for quantification of extracellular and intracellular levels of prostanoids, including prostaglandin E(2) (PGE(2)), PGD(2), PGD(2 alpha), 6-keto PGF(1 alpha), and TXB(2), in cultured cells using liquid chromatography/tandem mass spectrometry (LC/MS/MS), and we validated the LC/MS/MS methods. A solid-phase extraction cartridge was used for extraction of prostanoids. The prostanoids were separated by a C(18) column with an isocratic flow of acetonitrile/water/acetic acid (40:60:0.1, v/v/v). Calibration curves of extracellular measurement for the prostanoids were linear in the range from 0.1 to 100 ng/mL (r(2) > 0.999), and those of intracellular measurement were linear in the range from 0.05 to 50 ng (r(2) > 0.999). Validation assessment showed that both methods of extracellular and intracellular measurements were highly reliable with good accuracy and precision. We also applied the methods to human airway epithelial Calu-3 cells and human lung adenocarcinoma epithelial A549 cells.

Prostanoids are bioactive substances that contribute to various biological and pathological processes. To evaluate both extracellular and intracellular levels of prostanoids at the same time, we developed methods for quantification of extracellular and intracellular levels of prostanoids, including prostaglandin E(2) (PGE(2)), PGD(2), PGD(2 alpha), 6-keto PGF(1 alpha), and TXB(2), in cultured cells using liquid chromatography/tandem mass spectrometry (LC/MS/MS), and we validated the LC/MS/MS methods. A solid-phase extraction cartridge was used for extraction of prostanoids. The prostanoids were separated by a C(18) column with an isocratic flow of acetonitrile/water/acetic acid (40:60:0.1, v/v/v). Calibration curves of extracellular measurement for the prostanoids were linear in the range from 0.1 to 100 ng/mL (r(2) > 0.999), and those of intracellular measurement were linear in the range from 0.05 to 50 ng (r(2) > 0.999). Validation assessment showed that both methods of extracellular and intracellular measurements were highly reliable with good accuracy and precision. We also applied the methods to human airway epithelial Calu-3 cells and human lung adenocarcinoma epithelial A549 cells.

Prostanoids are bioactive substances that contribute to various biological and pathological processes. To evaluate both extracellular and intracellular levels of prostanoids at the same time, we developed methods for quantification of extracellular and intracellular levels of prostanoids, including prostaglandin E(2) (PGE(2)), PGD(2), PGD(2 alpha), 6-keto PGF(1 alpha), and TXB(2), in cultured cells using liquid chromatography/tandem mass spectrometry (LC/MS/MS), and we validated the LC/MS/MS methods. A solid-phase extraction cartridge was used for extraction of prostanoids. The prostanoids were separated by a C(18) column with an isocratic flow of acetonitrile/water/acetic acid (40:60:0.1, v/v/v). Calibration curves of extracellular measurement for the prostanoids were linear in the range from 0.1 to 100 ng/mL (r(2) > 0.999), and those of intracellular measurement were linear in the range from 0.05 to 50 ng (r(2) > 0.999). Validation assessment showed that both methods of extracellular and intracellular measurements were highly reliable with good accuracy and precision. We also applied the methods to human airway epithelial Calu-3 cells and human lung adenocarcinoma epithelial A549 cells.

A liquid chromatography tandem mass spectrometry method is described for the analysis of buprenorphine and norbuprenorphine in whole blood. Linearity was achieved between 0.2-5 ng/g for buprenorphine and 0.5-5 ng/g for norbuprenorphine. Stability studies on spiked whole blood and an authentic sample showed no degradation of buprenorphine- and norbuprenorphine-glucuronide to their respective aglycones. Buprenorphine and norbuprenorphine showed some degradation when stored at 4 degrees C for three weeks, but was stable when stored at -20 degrees C for 4 weeks. The method was applied to forensic cases of driving under the influence of drugs (DUID) and petty drug offences (PDO) during 2007-2009. Out of 2459 cases analyzed, 322 were positive for both buprenorphine and norbuprenorphine (13%), 219 for buprenorphine only (9%), and 12 for norbuprenorphine only (0.5%). The mean and median concentrations (N = 322) were 1.7 and 1.0 ng/g, respectively, for buprenorphine and norbuprenorphine. The mean and median norbuprenorphine/buprenorphine ratios were 1.5 and 1.1, respectively. There was no significant difference in concentration ratios for DUID and PDO cases (p andgt; 0.05). We conclude that the described method for analysis of buprenorphine and norbuprenorphine in whole blood could be used to investigate use or misuse of buprenorphine but that many of the cases presented with very low concentrations of buprenorphine. We also conclude that analysis should be performed within two weeks unless samples are stored frozen prior to analysis.

The objective of this study was to evaluate the analytical performance of the Abbott ARCHITECT Cyclosporine (CsA) immunoassay in 7 clinical laboratories in comparison to liquid chromatography/tandem mass spectrometry (LC/MS/MS), Abbott TDx, Cobas Integra 800, and the Dade Dimension Xpand immunoassay. The ARCHITECT assay uses a whole blood specimen, a pretreatment step with organic reagents to precipitate proteins and extract the drug, followed by a 2-step automated immunoassay with magnetic microparticles coated with anti-CsA antibody and an acridinium-CsA tracer. Imprecision testing at the 7 evaluation sites gave a range of total % coefficient of variations of 7.5%-12.2% at 87.5 ng/mL, 6.6%-14.3% at 411 ng/mL, and 5.2%-10.7% at 916 ng/mL. The lower limit of quantification ranged from 12 to 20 ng/mL. Purified CsA metabolites AM1, AM1c, AM4N, AM9, and AM19 were tested in whole blood by the ARCHITECT assay and showed minimal cross-reactivity at all 7 sites. In particular, AM1 and AM9 cross-reactivity in the ARCHITECT assay, ranged from -2.5% to 0.2% and -0.8% to 2.2%, respectively, and was significantly lower than for the TDx assay, in which the values were 3.2% and 16.1%, respectively. Comparable testing of metabolites in the Dade Dimension Xpand assay at 2 evaluation sites showed cross-reactivity to AM4N (6.4% and 6.8%) and AM9 (2.6% and 3.6%) and testing on the Roche Integra 800 showed cross-reactivity to AM1c (2.4%), AM9 (10.7%), and AM19 (2.8%). Cyclosporine International Proficiency Testing Scheme samples, consisting of both pooled specimens from patients receiving CsA therapy as well as whole-blood specimens supplemented with CsA, were tested by the ARCHITECT assay at 6 sites and showed an average bias of -24 to -58 ng/mL versus LC/MSMS CsA and -2 to -37 ng/mL versus AxSYM CsA. Studies were performed with the ARCHITECT CsA assay on patient specimens with the following results: ARCHITECT CsA assay versus LC/MSMS, average bias of 31 ng/mL; ARCHITECT versus the Da

The Henares-Jarama-Tajo river system is the largest drainage basin in the Province of Madrid, Spain. This area is characterized by the presence of intensive urban and industrial activities influenced by a continental Mediterranean climate with rainfalls presenting substantial fluctuations along the different seasons. This research aimed to monitor seasonal variations in concentrations of 22 pharmaceutically active compounds (PhACs) in this river system and to establish the potential risk of sublethal effects on aquatic organisms. A total of 10 sampling sites were selected along the river system with samples collected in each of the four seasons during a year-round schedule. Most of the PhACs detected were present in sampling sites downstream in the vicinity of the most populated cities (i.e. Madrid, Guadalajara and Alcalá de Henares). Only two PhACs, fluoxetine and paraxantine, were detected in all sites regardless of the season, and showed median (± interquartile range) concentrations of 21.4 (± 31.2) ng L- 1 and 8.5 (± 5.3) ng L- 1, respectively. Other PhACs were detected with a frequency > 80% and included, caffeine, diphenylhydantoin, hydrochlorotiazide, ibuprofen, ketoprofen, diclofenac, sulfamethoxazole, atenolol, naproxen, carbamazepine and propanolol. Seasonal variations were observed with the highest concentrations in December and the lowest in September. By combining measured environmental concentrations with toxicity data (either publicly available or obtained experimentally in our laboratory), and by calculating an Maximum Risk Index (MaxRI) that each combination of PhACs should have for non exceeding the risk threshold, a high potential for long-term risk (MaxRI < 10) was estimated for most of the sampling sites and sampling dates. This research allowed the characterization of the potential risk for each of the PhACs to exert sublethal effects on aquatic organisms using acute screening methods, justifying the need for chronic data in order to refi

This study presents the first investigation into the occurrence of N-nitrosodiphenylamine (NDPhA), a thermally unstable nitrosamine, in drinking water from Canada and the United States. NDPhA, in addition to 8 other nitrosamines, were determined in water samples collected from 38 drinking water distribution systems using high performance liquid chromatography-tandem mass spectrometry (LC/MS/MS). Of the 9 nitrosamines analyzed, NDPhA, NMor and NDMA were detected. Our results show that nitrosamine concentrations change in the distribution system, demonstrating that measurements done solely at the water treatment plant may misestimate the nitrosamine concentrations consumers are exposed to and that NDPhA exposure should be explored. These results are useful for directing future exposure assessments and chloramination treatment.

A comprehensive investigation of sensitive ecosystems in South Florida with the main goal of determining the identity, spatial distribution, and sources of both organic biocides and trace elements in different environmental compartments is reported. This study presents the development and validation of a fractionation and isolation method of twelve polar acidic herbicides commonly applied in the vicinity of the study areas, including e.g. 2,4-D, MCPA, dichlorprop, mecroprop, picloram in surface water. Solid phase extraction (SPE) was used to isolate the analytes from abiotic matrices containing large amounts of dissolved organic material. Atmospheric-pressure ionization (API) with electrospray ionization in negative mode (ESP-) in a Quadrupole Ion Trap mass spectrometer was used to perform the characterization of the herbicides of interest. The application of Laser Ablation-ICP-MS methodology in the analysis of soils and sediments is reported in this study. The analytical performance of the method was evaluated on certified standards and real soil and sediment samples. Residential soils were analyzed to evaluate feasibility of using the powerful technique as a routine and rapid method to monitor potential contaminated sites. Forty eight sediments were also collected from semi pristine areas in South Florida to conduct screening of baseline levels of bioavailable elements in support of risk evaluation. The LA-ICP-MS data were used to perform a statistical evaluation of the elemental composition as a tool for environmental forensics. A LA-ICP-MS protocol was also developed and optimized for the elemental analysis of a wide range of elements in polymeric filters containing atmospheric dust. A quantitative strategy based on internal and external standards allowed for a rapid determination of airborne trace elements in filters containing both contemporary African dust and local dust emissions. These distributions were used to qualitative and quantitative assess differenc

A fast, sensitive and specific LC/MS/MS method for the simultaneous analysis of oxcarbazepine (OXC), 10-hydroxycarbazepine (MHD) and trans-diol-carbazepine (DHD), in human serum, has been developed and validated. Serum drugs were extracted by C8 solid-phase cartridges (SPE) and separated in less than 3 min on a C18 reverse-phase column using an isocratic elution. A tandem mass spectrometer, as detector, was used for quantitative analysis in positive mode by a multiple reaction monitoring. Calibration curves, obtained on two ranges of concentration (0.78-50 mg/L for MHD and 0.078-5.0 mg/L for OXC and DHD), showed correlation coefficients (r) better than 0.997. Within day and between days quality controls imprecision, as CV%, ranged from 0.3 to 4.6% and from 1.9 to 5.8%, respectively. Cyheptamide (CYE) was used as internal standard. No detectable carry-over and no relevant cross-talk and matrix effect occurred. Samples from 24 treated patients were analysed and drug serum concentrations obtained by this method are in agreement with those of other methods and also are well correlated (r = 0.88) in comparison to our routine HPLC-UV method. Based on the analytical results and short run time, the method is suitable to support routine analysis of therapeutic drugs monitoring from human serum of treated patients or for pharmacokinetic studies. © 2007 Elsevier B.V. All rights reserved

An LC-MS-MS method was validated for the quantitation of a beta (3) agonist (A) in human urine to support Phase I studies. A was designed to accelerate metabolism for weight reduction. During assay development a significant loss of A was apparent from frozen urine quality control samples. The addition of 0.75% bovine serum albumin (BSA) in urine (v/v) was required to maximize the recovery of A from urine. Urine samples were basified and extracted into methyl t-butyl ether-isopropyl alcohol (90:10, v/v). The organic layer was washed, evaporated, reconstituted, and injected onto a 5 cm, CS HPLC column prior to MS-MS analysis. The standard curve was linear from 5 to 500 ng/ml. Intraday precision for peak area ratios from BSA urine samples at seven separate concentrations over a range of 5-500 ng/ml (n = 5) was <4.0% and calculated concentrations were within 91-115% of nominal concentrations. Interday precision for BSA urine quality control (QC) samples at four separate concentrations (n = 10 of each) was <5.0% and individual calculated concentrations were within 90-111% of nominal concentrations, This work emphasizes that potential metabolites and quality control standards should be prepared and assayed as early as possible in method development., especially before the sample collection section of the clinical protocol is prepared. The methods described here have wide utility to other compounds containing basic benzene sulfonamides and to beta (3) agonist candidates, (C) 2001 Elsevier Science B.V. All rights reserved.

Předložená bakalářská práce se zabývá metodami vhodnými k analýze fenolických látek, jako jsou polyfenolické kyseliny či flavonoidy. V teoretické části byla provedena podrobná literární rešerše, která shrnuje především moderní instrumentální techniky běžně využívané ke stanovení polyfenolů. V experimentální části byly pak analyzovány vybrané standardní polyfenolické sloučeniny s využitím kombinované metody HPLC/ESI-MS s off-line a on-line detekcí. Spektra jednotlivých standardů i jejich směsí byla stanovena v režimu MS full scan a pomocí tandemové hmotnostní spektrometrie, a to v kladném i záporném módu. Byly identifikovány kvasi-molekulární ionty reserpinu (PI 609,9, NI 607,7), kyseliny chlorogenové (NI 353), kvercetinu (PI 303,5, NI 301,5), rutinu (PI 611, NI 609) a morinu (PI 303,1, NI 301,1). Produktové ionty pak byly získány štěpením v režimu MS/MS full scan. Jako charakteristické štěpy byly určeny u kyseliny chlorogenové čára s m/z 191 (NI), u kvercetinu 229,1 a 257,1 (PI) a 179,0 a 151 (NI), u rutinu 301,0 (NI) a u morinu 285,1 a 257,1 (PI) a 283,2, 273,2, 257,1, 229,1 (NI). Štěp rutinu 301 byl dále fragmentován pomocí MS3/full scan za vzniku fragmentů 179 a 151,1 (NI). V optimalizačním experimentu byly stanoveny podmínky vhodné pro HPLC separaci polyfenolů zahrnující gradientovou eluci a separační systém s chromatografickou kolonou Restek. Ve spojení LC/MS bylo stanoveno, že jedině on-line detekce v záporném módu vede k uspokojivým výsledkům ve stanovení polyfenolů., Presented bachelor thesis was focused on suitable methods for analysis of phenolics, especially modern instrumental methods were studied. In experimental part some standard phenolic compounds were analysed using combined technique HPLC/ESI-MS with off-line and/or on-line detection. Mass spectra of individual stadards and/or mixtures were determined in MS full scan and/or MS/MS full scan mode. Ionisation of chosen standard compounds was done in pozitive and/or negative mode. Parent ions of followed compounds were identified: reserpine (PI 609.9, NI 607.7), acid chlorogenic (NI 353), quercetin (PI 303.5, NI 301.5), rutin (PI 611, NI 609), morin (PI 303.1, NI 301.1). Typical fragments of studied standards were produced using MS/MS full scan mode. By fragmentation characteristic product ions were identified: acid chlorogenic (NI 191), quercetin (PI: 229.1 and 257.1; NI: 179.0 and 151.0), rutin (in MS/MS NI: 301; in MS3 NI: 179, 151.1), morin (PI: 285.1 a 257.1; NI: 283.2, 273.2, 257.1, 229.1). Optimal conditions of phenolic HPLC separation were determined including gradient elution and Restek column use. In conclusion on-line HPLC/MS detection using negative ionization was observed as the best configuration for phenolic analysis.