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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Avaliação da bioequivalência de comprimidos contendo 10 mg de cloridrato de ciclobenzaprina / Bioequivalence avaliation of tables contain 10 mg of cyclobenzaprine hydrochloride

Tatiane Maria de Lima Souza Brioschi 13 November 2006 (has links)
A ciclobenzaprina é um relaxante muscular de ação central estruturalmente similar aos antidepressivos tricíclicos. O objetivo deste trabalho foi avaliar a bioequivalência de comprimidos contendo 10 mg de cloridrato de ciclobenzaprina em voluntários sadios. O estudo de bioequivalência entre o produto teste (Miosan®) e referência (Flexeril®) foi do tipo randomizado, aberto e cruzado. Os produtos foram administrados por via oral aos voluntários em dose única de 10 mg de cloridrato de ciclobenzaprina. Amostras de sangue foram coletadas até 240 horas após a administração do fármaco e quantificadas por método previamente validado através de cromatografia líquida de alta eficiência acoplada a um detector de massas. As curvas médias de decaimento plasmático dos produtos teste (Miosan®) e referência (Flexeril®) foram semelhantes ASC0-t (teste: 193,00 ngxh/mL; referência: 191,66 ngxh/mL) e ASC0∞ (teste: 211,34 ngxh/mL; referência: 209,35 ngxh/mL). Assim como os parâmetros farmacocinéticos relativos à absorção de ciclobenzaprina, Cmax (teste: 7,16 ng/mL; referência: 6,95 ng/mL), tmax (teste: 4,61 h; referência: 4,48 h), Ka (referência: 0,79; teste: 0,67) e t(1/2)a (referência: 1,79 h; teste: 2,02 h). Os parâmetros farmacocinéticos relativos à eliminação plasmática de ciclobenzaprina Cl (teste: 31,15 L/h; referência: 31,73 L/h), Vd (teste: 1378,54 L e referência (1357,87 L), kß (referência: 0,08; teste: 0,08), t(1/2)ß (referência: 9,43 h; teste: 9,20 h), k&#947 (referência: 0,02; teste: 0,02) e t(1/2)&#947 (referência: 32,92 h; teste: 31,67 h) também apresentaram-se semelhantes entre os dois produtos. A análise multivariada realizada por meio da análise de variância (ANOVA), para a avaliação dos efeitos produto, grupo e período, revelou a ausência destes efeitos, indicando que o delineamento do estudo foi adequado. Os resultados do intervalo de confiança (I.C. 90 %) para a razão de Cmax (93,0 % - 112,0 %), ASC0-t(92,6 % - 111,1 %) e ASC0&#8734 (93,1 % - 110,4 %), encontram-se dentro dos limites estabelecidos pela ANVISA e FDA (80 - 125 %). A análise estatística dos parâmetros Cmax, ASC0-t e ASC0-&#8734 indicam que não há diferenças entre os dois produtos contendo 10 mg de cloridrato de ciclobenzaprina. Com base nos resultados deste estudo, conclui-se que os produtos avaliados são bioequivalentes e podem ser considerados intercambiáveis na terapêutica. / Cyclobenzaprine is a centrally acting muscle relaxant that has similarity with a tricyclic antidepressant. The purpose of this study was to evaluate the bioequivalence of two brands of cyclobenzaprine 10 mg tablets in healthy volunteers. The procedure of bioequivalence between test product (Miosan®) and reference product (Flexeril®) was a randomized, open and crossover study. The products were administered in a single oral dose of 10 mg of cyclobenzaprine hydrochloride to healthy volunteers. Blood samples were collected until 240 hours after administration and quantified by validated method using high-pressure liquid chromatography with mass spectrometric detection. The average plasmatic decay curves of test (Miosan&#174) and reference (Flexeril&#174) products were similar ASC0-t (test: 193,00 ngxh/mL; reference: 191,66 ngxh/mL), in the same way that absorption parameters Cmax (test: 7,16 ng/mL; reference: 6,95 ng/mL), tmax (test: 4,61 h; reference: 4,48 h), Ka (reference: 0,79; test: 0,67) e t(1/2)a (reference: 1,79 h; test: 2,02 h). The elimination parameters Cl (test: 31,15 L/h; reference: 31,73 L/h), Vd (test: 1378,54 L e reference (1357,87 L), k&#914 (reference: 0,08; test: 0,08), t(1/2)&#946 (reference: 9,43 h; test: 9,20 h), k&#947 (reference: 0,02; test: 0,02) e t(1/2)&#947 (reference: 32,92 h; test: 31,67 h) were similar between products too. The multivariate analysis accomplished trough analysis of variance (ANOVA), for assessment of product, group and period effects, revealed the absence of any of these effects in the present study, indicating that the crossover design was properly performed. The 90 % confidence intervals for the ratio of Cmax(93,0 % - 112,0 %), AUC0-t(92,6 % - 111,1 %) and AUC0&#8734 (93,1 % - 110,4 %) values for the test and reference products are within the 80 - 125 % interval proposed by ANVISA e FDA. Statistical analysis of Cmax, AUC0-t e AUC0-&#8734 parameters indicated no significant difference between two brands of 10 mg cyclobenzaprine hydrochloride products. Based in the results of this study, we can conclude that the two products are bioequivalent and can be considered interchangeable in the medical practice.
22

Testing selected micro-contaminants for their applicability as water quality indicators

Nödler, Karsten 31 July 2012 (has links)
Die Verwendung anthropogener organischer Spurenstoffe wie beispielsweise Pharmazeutika, Lifestyle-Produkte, Biozide und Pestizide als Indikatoren für die Bewertung der Wasserqualität hat großes Interesse in der Wissenschaftsgemeinde geweckt, und die Verwendung dieser Substanzen als Indikatoren für die Prozessoptimierung, Quellzuordnung und zur Abschätzung des Ausmaßes einer möglichen Kontamination (z. B. den Abwasseranteil von Oberflächen- und Grundwasser) besitzt ein sehr großes Anwendungspotential. Die hier präsentierte Arbeit ist die erfolgreiche und konsequente Weiterführung bestehender Forschungsaktivitäten zur Eignung ausgewählter Spurenstoffe als Indikatoren für die Bewertung der Wasserqualität, ihrem Vorkommen und Verhalten in der Umwelt sowie ihrer Redox-spezifischen Transformation. Um eine Substanz als Indikator verwenden zu können, müssen sensitive und selektive Analysenmethoden verfügbar sein. In der vorliegenden Arbeit wird die Entwicklung einer Multimethode für den Nachweis von 46 basischen, neutralen und sauren Analyten mittels der Hochleistungs-Flüssigchromatographie und Elektronenspray-Ionisation (ESI) mit anschließender Tandem-Massenspektrometrie (HPLC-ESI-MS/MS) beschrieben. Das ausgewählte Analytenspektrum deckt einen weiten Bereich hinsichtlich der Polarität der Stoffe (log Kow <0–5,9) sowie ihrer repräsentierten Kontaminationsquellen ab. Die Besonderheit der entwickelten Methode stellt die simultane Festphasenanreicherung (SPE), Trennung und Detektion aller Analyten dar. Um dieses realisieren zu können, wird das ESI-Interface in beiden möglichen Operationsmodi (+/−) verwendet, so dass pro Probe nur eine Injektion notwendig ist. Die Bestimmungsgrenzen der Methode in Fluss- und Meerwasser liegen im Bereich weniger ng/L. Im weiteren Verlauf der Arbeit wird die hohe Flexibilität der Methode (Integration zusätzlicher Analyten und Anpassung an andere Wassertypen) demonstriert. Im darauf folgenden Abschnitt werden die Ergebnisse eines intensiven Fluss-Monitorings vorgestellt. Der Fokus liegt dabei auf der Korrelation von 41 Spurenstoffen mit Kalium (K+) und deren räumlichen und zeitlichen Varianz. Da Urin je nach K+-Hintergrundkonzentration des Gewässers eine signifikante K+-Quelle darstellen kann, ist in Gewässern mit hohem Abwasseranteil eine positive Korrelation von abwasserbürtigen Stoffen und K+ zu erwarten. Diese Korrelation ist für Stoffe mit folgenden Charakteristika bestätigt worden: 1) Kläranlagenabläufe sind die Hauptquelle der Substanz; 2) Die Fracht der Substanz in der Kläranlage ist nur geringen zeitlichen Schwankungen unterworfen; und 3) Hohe Persistenz der Verbindung bei der Abwasserbehandlung und in der Umwelt. Neben anderen Spurenstoffen zeigen Carbamazepin, Sulfamethoxazol und Tolyltriazol die beste Korrelation. Darüber hinaus sind die K+-Äquivalente der einzelnen Stoffe offensichtlich abhängig von Landnutzung und Bevölkerungsstruktur im Einzugsgebiet des untersuchten Flussabschnitts. Eine Korrelation mit K+ zeigt, dass die Konzentration des korrelierenden Spurenstoffs nur vom Abfluss des Fließgewässers abhängig ist. Nach diesem Konzept könnte die Vorhersage der Konzentration entsprechender Spurenstoffe an bestimmten Flussabschnitten erheblich vereinfacht werden. Analog zu den genannten Charakteristika 1–3 kann der Ansatz zur Quellidentifizierung neu auftretender/identifizierter Substanzen genutzt werden. Darüber hinaus könnten Eintragsfunktionen für die korrelierenden Spurenstoffe hinsichtlich Oberflächenwasser/Grundwasser-Interaktion hergeleitet werden. Dies würde eine realistischere Bewertung der Reinigungsleistung von Anlagen zur (künstlichen) Grundwasseranreicherung ermöglichen. Anschließend wird eine Methode präsentiert, mit Hilfe derer sich das Volumen von schnell transportiertem, unbehandeltem Abwasser in einem Karstaquifer abschätzen lässt. Eine Kontamination mit unbehandeltem Abwasser und die damit verbundene bakterielle Belastung stellen eine ernsthafte Bedrohung für die Trinkwasserqualität und die öffentliche Gesundheit dar. Das Ausmaß einer Kontamination quantifizieren zu können ist allerdings meist problematisch. Daher wurde ein bereits bekannter Massenbilanzansatz der aktuellen Fragestellung angepasst. In die Berechnung der Abwassermenge fließen ein: Die Coffein-Fracht an der Quelle, die übliche Coffein-Belastung in unbehandeltem Abwasser und der tägliche durchschnittliche Trinkwasserverbrauch pro Person im beobachteten Quelleinzugsgebiet. Der entwickelte Ansatz wurde zur Berechnung der täglich zuströmenden Abwassermenge an einem bereits gut charakterisierten Karstaquifer (Gallusquelle, Deutschland) angewendet. Weiterhin werden die Ergebnisse einer Mikrokosmos-Studie zur Transformation des Antibiotikums Sulfamethoxazol (SMX) unter denitrifizierenden Bedingungen vorgestellt. Ein selektiver Reaktionsmechanismus mit den unter denitrifizierenden Bedingungen gebildeten N-Spezies Stickstoffmonoxid (NO) und Nitrit (NO2−) ist die zugrunde liegende Arbeitshypothese und die Bildung der daraus abgeleiteten Transformationsprodukte (TP) 4-Nitro-N-(5-methylisoxazol-3-yl)-benzenesulfonamid (4-Nitro-SMX) und N-(5-methylisoxazol-3-yl)-benzenesulfonamid (Desamino-SMX) während des zeitlichen Verlaufs eines Wasser/Sediment-Batchversuchs wird dargestellt. Beide TPs können auch in Umweltproben nachgewiesen werden. Unter geeigneten Reaktionsbedingungen kann das TP 4-Nitro-SMX zudem zu SMX retransformiert werden. Dies zeigt die hohe Relevanz der vorliegenden Arbeit hinsichtlich des Vorkommens und Verhaltens dieses Antibiotikums in der Umwelt und für das Monitoring der Wasserqualität. Darüber hinaus können Redox-spezifische TPs als Indikatoren für den reaktiven Stofftransport verwendet werden.
23

Analysis of toxigenic fungi and their mycotoxins in biotic interactions

Döll, Katharina 16 May 2013 (has links)
No description available.
24

New investigations into the Uluburun resin cargo

Stern, Ben, Heron, Carl P., Tellefsen, T., Serpico, M. January 2008 (has links)
Resin found within Canaanite amphorae from the Late Bronze Age shipwreck discovered off the coast of southwest Turkey at Uluburun has previously been identified as Pistacia sp. Although evidence from Egypt suggests that this resin was in high demand and typically transported in such amphorae, it has also been proposed that the amphorae contained wine, with the resin used to seal the interior surfaces and to flavour and/or preserve the wine. To attempt to resolve this question, we have analysed five samples of pistacia resin found in amphorae from the shipwreck using a range of analytical techniques which have used in the past for the analysis of wine residues: spot tests, FT-IR, and HPLC-MS-MS. As well as the archaeological samples, we have analysed modern samples of pistacia resin, leaves and fruit to determine the effectiveness of each technique and to exclude the possibility of false positive results. In addition to the analyses for wine we also detail analysis (GC-MS) of the terpenoids for the purpose of further molecular characterisation of the resin. Bulk stable isotope analysis was used in comparison with similar resins to attempt to identify the geographical origin of the resin.
25

Stereoselective disposition of bupropion and its three major metabolites : 4-hydroxybupropion, erythro-dihydrobupropion, and threo-dihydrobupropion / Stereoselective method to quantify bupropion and its three major metabolites, hydroxybupropion, erythro-dihydrobupropion, and threo-dihydrobupropion using HPLC-MS/MS

Masters, Andrea Renee 14 February 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / A version of this thesis was published as: Masters AR, McCoy M, Jones DR, and Desta Z. Stereoselective method to quantify bupropion and its three major metabolites, hydroxybupropion, erythro-dihydrobupropion, and threo-dihydrobupropion using HPLC-MS/MS. J Chromatography B Analyt Technol Biomed Life Sci 1015-1016:201-208, 2016. / Bupropion is a dual dopamine-norepinephrine uptake inhibitor and a nicotine receptor antagonist. Clinically, bupropion is given as a racemate for the management of depression, smoking cessation aid, and for the management of weight. Bupropion has also been targeted as a phenotypic probe of CYP2B6 activity. Bupropion metabolites are formed via oxidation (4-hydroxybupropion) through CYP2B6, and reduction (erythro- and threo-dihydrobupropion) through carbonyl reductases. These metabolites exhibit pharmacological activity, but little is known regarding their stereoselective disposition due to the lack of a chiral assay. A novel reversed phase chiral-HPLC-MS/MS method involving a simple liquid-liquid extraction procedure and a small plasma sample volume (50µL) was developed that allowed simultaneous separation and quantification of enantiomers of bupropion, 4-hydroxybupropion, and those of threo- and erythro-dihydrobupropion in human plasma. This method was successfully implemented to determine the unique stereoselective disposition of bupropion and its metabolites in 15 human volunteers administered a single 100 mg oral dose of racemic bupropion. Significant differences (p<0.05) in the stereoselective metabolism were observed for all of the enantiomers. The highest plasma exposure (AUC0-∞) was (2R, 3R)-4-hydoxybupropion, almost 65 fold higher, than (2S, 3S)-4-hydoxybupropion, and over 32 fold greater than the parent R-bupropion. The second highest plasma exposure was threo-dihydrobupropion A, which was almost 5 fold higher than threo-dihydrobupropion B. (Nomenclature of the enantiomers for erythro- and threo-dihydrobupropion was based on the chromatography of the first eluting peak as “A” and the second eluting peak as “B”.) Threo-dihydrobupropion A and B showed the most significant difference between the racemic and enantiomer profiles. Although the AUC was greater for threo-dihydrobupropion B, threo-dihydrobupropion A had a significantly (p<0.05) higher Cmax. The half-life for threo-dihydrobupropion A and erythro-dihydrobupropion A were the longest for all analytes, which could indicate accumulation in multiple dosing. The importance of this study was, for the first time, to be able to characterize the stereoselective metabolism of bupropion and its three major metabolites. This new method and subsequent pharmacokinetic data should enhance further research into bupropion stereoselective metabolism, drug interactions, and effect. / A version of this thesis was published as: Masters AR, McCoy M, Jones DR, and Desta Z. Stereoselective method to quantify bupropion and its three major metabolites, hydroxybupropion, erythro-dihydrobupropion, and threo-dihydrobupropion using HPLC-MS/MS. J Chromatography B Analyt Technol Biomed Life Sci 1015-1016:201-208, 2016.
26

Hexabromcyclododecan

Esslinger, Susanne 14 November 2013 (has links)
Das Ziel dieser Arbeit war die Untersuchung des enantiomerenspezifischen Umweltverhaltens des Flammschutzmittels Hexabromcyclododecan (HBCD). Zu Beginn erfolgte daher die Optimierung und Validierung eines enantiomerenspezifischen Analysenverfahrens für die Bestimmung von HBCD in Biota. Die errechneten mittleren Wiederfindungen lagen im Bereich von 100-102 % und die Nachweisgrenzen zwischen 0,131 und 0,255 pg g-1. Untersuchungen zur ubiquitären Verteilung von HBCD erfolgten an Eiern der Silbermöwe deutscher Nord- und Ostseeinseln (Probenahme 1988-2008). In allen Fällen dominierte alpha-HBCD das Diastereomerenmuster, wobei eine bevorzugte Anreicherung von (-)-alpha-HBCD sowie ein zeitlicher Trend aller Enantiomeren-Gehalte festgestellt wurde. Zur Klärung der Frage einer Bioakkumulation sowie -isomerisierung der HBCD-Stereoisomere erfolgten Langzeit-Fütterungsversuche an Spiegelkarpfen. Die Untersuchungen ergaben eine signifikante Akkumulation des jeweils gefütterten HBCD-Enantiomers, jedoch konnte die Hypothese der Bioisomerisierung nicht bestätigt werden. Ein weiterer Schwerpunkt lag in Untersuchungen zur cytochromabhängigen enantiomerenspezifischen Biotransformation von HBCD im Rahmen des Metabolismus an Lebermikrosomen diverser Spezies. Hier konnte gezeigt werden, dass HBCD dem Phase I-Metabolismus unterliegt und hydroxyliert wird. Dabei weist jedes HBCD-Enantiomer ein spezifisches Metabolitenmuster auf, was eine Zuordnung der hydroxylierten Verbindungen zum entsprechenden HBCD-Enantiomer erlaubt. Anhand von Zeitreihen sowie der Berechnung von Halbwertszeiten konnte der Verdacht eines enantiomerenspezifischen Metabolismus in Richtung einer Anreicherung von (-)-alpha- und (+)-gamma-HBCD bestätigt werden. Inkubationsansätze mit reinen Cytochrom (CYP)-Isoformen sowie molekülmechanische Berechnungen legen die Vermutung nahe, dass dem CYP3A4 eine Schlüsselrolle bei der Metabolisierung von HBCD zukommt. / The main emphasis of this thesis was on the enantio-specific environmental behaviour of the polybrominated flame retardant hexabromocyclododecane (HBCD). Initially, an enantio-specific analytical method for the determination of HBCD in biota was optimised and validated. The calculated mean recoveries ranged from 100 to 102 % and the limits of detection are in the range of 0.131 to 0.255 pg g-1. First investigations of the ubiquitous environmental distribution of HBCD were performed using herring gull eggs from different islands in the North and Baltic Sea (sampling 1988 to 2008). In all cases alpha-HBCD was the predominant diastereomer. Significant deviations from the racemic mixture revealed a preferred enrichment of the first eluting (-)-alpha-HBCD. In addition, a temporal trend of HBCD levels was observed. To clarify the issue of accumulation as well as bioisomerisation of HBCD stereoisomers, a long-term feeding study with mirror carps was performed. The results showed an accumulation of each initially fed HBCD enantiomer, but hypothesis of a bioisomerisation could not be confirmed. Another important focus of this work was to study the cytochrome-dependent enantio-specific biotransformation of HBCD enantiomers in various species of liver microsomes. It was shown that HBCD is subject to phase I metabolism. In the course of this process, HBCD is metabolised to hydroxylated products, whereas each HBCD enantiomer results in a specific metabolite pattern allowing the allocation of the corresponding hydroxylated compounds. Investigation of time series as well as the calculation of half-lives, the hypothesis of an enantio-specific metabolism towards an enrichment of (-)-alpha- and (+)-gamma-HBCD could be confirmed. Incubation mixtures with pure cytochrome (CYP) isoforms, as well as molecular mechanic calculations suggest that CYP3A4 plays a key role in the biotransformation processes of HBCD.
27

Desenvolvimento farmacotécnico e analítico de comprimidos revestidos de montelucaste: equivalência farmacêutica e bioequivalência / Pharmaceutical and analytical development film coated tablets of montelukast: pharmaceutical equivalence and bioequivalence

ALVES, Carina Pimentel Itapema 18 March 2011 (has links)
Made available in DSpace on 2014-07-29T15:25:22Z (GMT). No. of bitstreams: 1 Tese Carina-pos defesa.pdf: 485460 bytes, checksum: 2ca505db4ca73a05349dd92fbfc7df1d (MD5) Previous issue date: 2011-03-18 / Montelukast is a potent reversible selective inhibitor of cysteinilleukotrien- 1 receptor, avoiding that these mediators promote the asthmatic response. Its commercialization in Brazil, as a terminated product, is protected by patent up to 2010. Once the active ingredient Montelukast is recent in the pharmaceutical market and there is no methodology description in official compendiums capable to assure the quality of new formulations, the objective of this paper was the pharmaceutics of montelukast film coated tablets, the development and the validation of analytical and bioanalytical methodologies foreseeing the pharmaceutical equivalence and bioequivalence with the reference medication of the market. With this purpose, some physicalchemical parameters were characterized, assay and dissolution methodologies were developed and validated per high performance liquid chromatography with ultraviolet detection (HPLC-UV) for the quantification of montelukast present in 10.0mg film coated tablets. The quantification of montelukast sodium in human plasma was performed using Loratadine as internal standard and high performance liquid chromatography attached to mass detector (HPLC - MS / MS). The active ingredient was extracted from the human plasma using precipitation extraction. The results found for the parameters of specificity, linearity, accuracy, precision, quantification and detection limits and stability in the methodologies validation confirm they were adequate for the objective proposed. The analytical methodologies developed and validated were applied in the pharmaceutics of the tablets for the determination of the formulation similar to the market reference medication Singulair®. This formulation was submitted to stability assays to assure its quality and to allow the performance of pharmaceutical equivalence and bioequivalence with the purpose of registering as a generic medication. / O Montelucaste é um potente inibidor seletivo reversível do receptor cisteinil-leucotrieno-1, evitando que os mediadores provoquem a resposta asmática. Sua comercialização no Brasil, na forma de produto acabado, é protegida por patente até 2010. Uma vez que o fármaco Montelucaste é recente no mercado farmacêutico e não há descrição de metodologia em compêndios oficiais capaz de assegurar a qualidade das novas formulações, o objetivo deste trabalho foi o desenvolvimento farmacotécnico de comprimidos revestidos de montelucaste, desenvolvimento e validação de métodos analítico e bioanalítico visando obtenção de equivalência farmacêutica e bioequivalência com o medicamento referência de mercado. Com esta finalidade, foram caracterizados alguns parâmetros físico-químicos, desenvolvidos e validados métodos de doseamento e dissolução por cromatografia líquida de alta eficiência com detecção ultravioleta (HPLC-UV) para quantificação de montelucaste presente em comprimidos revestidos de 10,0 mg. A determinação de montelucaste sódico em plasma humano foi realizada utilizando-se loratadina como padrão interno e cromatografia líquida de alta eficiência acoplada a detector de massas (HPLC MS/MS). O fármaco foi extraído do plasma humano utilizando extração por precipitação. Os resultados encontrados dos parâmetros de especificidade, linearidade, exatidão, precisão, limites de quantificação e detecção e estabilidade nas validações dos métodos confirmam que os mesmos foram adequados para a finalidade proposta. Os métodos analíticos desenvolvidos e validados foram aplicados no desenvolvimento farmacotécnico dos comprimidos para determinação de uma formulação próxima ao medicamento referência de mercado Singulair®. Esta formulação foi submetida a ensaios de estabilidade para assegurar sua qualidade e permitir a realização de equivalência e bioequivalência farmacêutica com o intuito de registro como medicamento genérico.
28

Behavioral Assessment and HPLC/MS/MS Identification of the Synthetic Cannabinoid, CP47,497, in Mice

Samano, Kimberly L 26 March 2014 (has links)
CP47,497 and other synthetic cannabinoid compounds were incipiently synthesized as research tools to investigate the mechanisms by which marijuana affects the brain and to aid in the development of therapeutic agents. Recently, these cannabinoid compounds have resurfaced in the designer drug market, marketed as “herbal incense products” (HIPs). Their popular use has resulted in an alarming rate of reported adverse effects and toxicities. Current legislation classified CP47,497 and several other synthetic cannabinoids compounds as Schedule I agents, but abuse of these compounds persists with serious consequences to public health and safety. In vivo studies examining the behavioral consequences of abused synthetic cannabinoids are limited. As a result, the goals of this research were to elucidate the acute and chronic pharmacological effects of CP47,497 and to develop a bioanalytical method for CP47,497 drug detection in mice. Cannabimimetic effects were evaluated in well-established in vivo models, the tetrad paradigm and drug discrimination assay. The tetrad test is comprised of four outcome measures sensitive to the primary psychoactive cannabinoid present in marijuana, delta-9-tetrahydrocannabinol (THC): catalepsy (bar test), antinociception (tail withdrawal latency), hypothermia, and decreases in spontaneous locomotor activity. While many pharmacological agents can produce one or a subset of these tetrad effects, drugs that activate CB1 receptors produce characteristic effects in all four parameters. An HPLC/MS/MS method was developed and confirmed the presence of CP47,497 in brain. We investigated whether CB1 receptors mediate the pharmacological effects of CP47,497. Cumulative dose-response experiments determined CP47,497 is more potent than THC in vivo in using multiple behavioral assays. Complementary pharmacological (CB1 receptor antagonist, rimonabant) and genetic (CB1 (-/-) mice) approaches were used to investigate whether CB1 receptors mediate the effects of CP47,497. Rimonabant (3 mg/kg or 10 mg/kg, depending on independent measure) blocked all cannabinoid-like pharmacological effects of CP47,497. Supporting these findings, CB1(-/-) mice were resistant to cannabimimetic effects of CP47,497. CP47,497 fully substituted for THC in the drug discrimination assay, with a potency of more than 5 times that of THC. Collectively, these results indicate that CP47,497 is markedly more potent (i.e. 5-8 fold) than THC, and its repeated administration produces tolerance to the cataleptic, antinociceptive, hypothermic and hypolocomotor effects in mice, with significant presentation of somatic withdrawal signs (paw flutter and head shakes) upon drug cessation. These findings are consistent with the high incidence of adverse events in humans abusing synthetic cannabinoids.
29

Adutos de DNA relacionados ao estresse oxidativo e glicação avançada em ratos diabéticos / DNA adducts related to oxidative stress and advanced glycation in diabetic rats.

Santos, Fabiana Almeida dos 17 October 2014 (has links)
O diabetes mellitus é considerado um dos problemas de saúde globalmente mais desafiadores do século 21. De acordo com as estimativas recentes do International Diabetes Federation - IDF, cerca de 382 milhões de pessoas são diabéticas e esse número tende a aumentar para além de 592 milhões em menos de 25 anos. Para melhor compreensão do Diabetes mellitus e suas complicações torna-se necessário buscar novos marcadores para a doença. O DM promove estresse oxidativo, inflamação e a formação de produtos avançados de glicação não enzimática (AGES), o que leva a dano tecidual no paciente diabético. Marcadores de dano oxidativo em proteínas e lipídeos na vigência do DM têm sido amplamente abordados na literatura, no entanto o estudo de lesões em DNA ainda requer mais atenção em modelos in vivo. Este trabalho teve como objetivo avaliar o dano oxidativo e resultante de glicação avançada em rim, fígado, cerebelo, sangue e urina de animais diabéticos, assim como a modulação do dano por diferentes períodos de tratamento com insulina, a fim de verificar se o controle da glicemia nos animais diabéticos protege contra a indução dos danos em biomoléculas. Para a indução do DM nos ratos Sprague-Dawley foram administrados 40 mg de STZ por kg de peso corpóreo por via intravenosa. Os níveis de MDA e 5-metildC foram avaliados por HPLC-DAD. A quantificação de HbA1c e dos adutos 1,N2-&#949;dGuo, 1,N6-&#949;dAdo, 8-oxodG e CEdG foi realizada por sistema HPLC-ESI-MS/MS. Os níveis de nitrito sérico foram determinados por leitura da absorbância em espectrofotômetro e a concentração de creatinina plasmática foi determinada por analisador bioquímico. Os resultados mostraram que as alterações metabólicas desencadeadas pela condição de hiperglicemia persistente não são prontamente revertidas após o controle da glicemia. Os níveis glicêmicos e de HbA1c apresentam diferença significativa entre os grupos de animais hiperglicêmicos e sadios, sendo observada uma queda dos valores de HbA1c somente a partir do tratamento com insulina por 6 semanas. Em plasma, rim e fígado as concentrações de MDA seguem o perfil de concentração de hemoglobina glicada (HbA1c), indicando que os eventos de glicação e estresse oxidativo podem estar relacionados. O controle glicêmico também apresentou efeito benéfico para a excreção de CEdG e 1,N6-&#949;dAdo em urina, apesar de ser observado a partir dos níveis de 8- oxodG que a hiperinsulinemia leva a um quadro de estresse oxidativo. As três lesões são geradas por vias distintas: glicação avançada, peroxidação lipídica e ROS. Portanto, além do controle glicêmico, é importante que se desenvolvam estratégias de intervenção nas vias bioquímicas alteradas pela condição de hiperglicemia, a fim de reduzir os riscos das complicações decorrentes do diabetes mellitus. / Diabetes mellitus is generally considered one of the most challenging health problems of the 21st century. According to recent estimates from the International Diabetes Federation - IDF, about 382 million people have diabetes and this number is expected to increase beyond 592 million in less than 25 years. For a better understanding of diabetes mellitus and its complications becomes necessary to search for new biomarkers for the disease. The DM promotes oxidative stress, inflammation and the formation of advanced glycation end products (AGEs), which leads to tissue damage in the diabetic patient. Markers of oxidative damage to proteins and lipids in the presence of DM have been widely discussed in literature, however the study of DNA lesions in vivo models still requires more attention. This study aimed to evaluate the oxidative damage and advanced glycation in the kidney, liver, cerebellum, blood and urine of diabetic animals, as well as damage modulation for different periods of insulin treatment in order to verify that the glycaemic control in diabetic animals protects against induction of biomolecules damage. For induction of diabetes in Sprague-Dawley rats were administered 40 mg STZ per kg body weight intravenously. MDA and 5-metildC were evaluated by HPLC-DAD. The quantification of HbA1c and adducts 1,N2-&#949;dGuo, 1,N6-&#949;dAdo, 8-oxodG and CEdG was performed by HPLC-ESI-MS / MS system. The serum nitrite was determined by reading the absorbance in a spectrophotometer and the plasma creatinine concentration was determined by biochemical analyzer. The results showed that metabolic changes triggered by the condition of persistent hyperglycemia are not readily reversed after glycemic control. Blood glucose and HbA1c levels are significantly different between the groups of hyperglycemic and healthy animals, and was observed a fall in HbA1c only from insulin treatment for 6 weeks. In plasma, kidney and liver concentrations follow the profile of MDA concentration of glycated hemoglobin (HbA1c), indicating that the events of glycation and oxidative stress may be related. Glycemic control also showed beneficial effect for urine excretion of CEdG and 1,N6-&#949;dAdo despite could be seen from 8-oxodG levels that the hyperinsulinaemia leads to a frame of oxidative stress. The three lesions are generated by distinct pathways: advanced glycation, lipid peroxidation and ROS. Therefore, beyond glycaemic control, it is important to develop intervention strategies in biochemical pathways altered by the condition of hyperglycemia in order to reduce the complications risk of diabetes mellitus.
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Adutos de DNA relacionados ao estresse oxidativo e glicação avançada em ratos diabéticos / DNA adducts related to oxidative stress and advanced glycation in diabetic rats.

Fabiana Almeida dos Santos 17 October 2014 (has links)
O diabetes mellitus é considerado um dos problemas de saúde globalmente mais desafiadores do século 21. De acordo com as estimativas recentes do International Diabetes Federation - IDF, cerca de 382 milhões de pessoas são diabéticas e esse número tende a aumentar para além de 592 milhões em menos de 25 anos. Para melhor compreensão do Diabetes mellitus e suas complicações torna-se necessário buscar novos marcadores para a doença. O DM promove estresse oxidativo, inflamação e a formação de produtos avançados de glicação não enzimática (AGES), o que leva a dano tecidual no paciente diabético. Marcadores de dano oxidativo em proteínas e lipídeos na vigência do DM têm sido amplamente abordados na literatura, no entanto o estudo de lesões em DNA ainda requer mais atenção em modelos in vivo. Este trabalho teve como objetivo avaliar o dano oxidativo e resultante de glicação avançada em rim, fígado, cerebelo, sangue e urina de animais diabéticos, assim como a modulação do dano por diferentes períodos de tratamento com insulina, a fim de verificar se o controle da glicemia nos animais diabéticos protege contra a indução dos danos em biomoléculas. Para a indução do DM nos ratos Sprague-Dawley foram administrados 40 mg de STZ por kg de peso corpóreo por via intravenosa. Os níveis de MDA e 5-metildC foram avaliados por HPLC-DAD. A quantificação de HbA1c e dos adutos 1,N2-&#949;dGuo, 1,N6-&#949;dAdo, 8-oxodG e CEdG foi realizada por sistema HPLC-ESI-MS/MS. Os níveis de nitrito sérico foram determinados por leitura da absorbância em espectrofotômetro e a concentração de creatinina plasmática foi determinada por analisador bioquímico. Os resultados mostraram que as alterações metabólicas desencadeadas pela condição de hiperglicemia persistente não são prontamente revertidas após o controle da glicemia. Os níveis glicêmicos e de HbA1c apresentam diferença significativa entre os grupos de animais hiperglicêmicos e sadios, sendo observada uma queda dos valores de HbA1c somente a partir do tratamento com insulina por 6 semanas. Em plasma, rim e fígado as concentrações de MDA seguem o perfil de concentração de hemoglobina glicada (HbA1c), indicando que os eventos de glicação e estresse oxidativo podem estar relacionados. O controle glicêmico também apresentou efeito benéfico para a excreção de CEdG e 1,N6-&#949;dAdo em urina, apesar de ser observado a partir dos níveis de 8- oxodG que a hiperinsulinemia leva a um quadro de estresse oxidativo. As três lesões são geradas por vias distintas: glicação avançada, peroxidação lipídica e ROS. Portanto, além do controle glicêmico, é importante que se desenvolvam estratégias de intervenção nas vias bioquímicas alteradas pela condição de hiperglicemia, a fim de reduzir os riscos das complicações decorrentes do diabetes mellitus. / Diabetes mellitus is generally considered one of the most challenging health problems of the 21st century. According to recent estimates from the International Diabetes Federation - IDF, about 382 million people have diabetes and this number is expected to increase beyond 592 million in less than 25 years. For a better understanding of diabetes mellitus and its complications becomes necessary to search for new biomarkers for the disease. The DM promotes oxidative stress, inflammation and the formation of advanced glycation end products (AGEs), which leads to tissue damage in the diabetic patient. Markers of oxidative damage to proteins and lipids in the presence of DM have been widely discussed in literature, however the study of DNA lesions in vivo models still requires more attention. This study aimed to evaluate the oxidative damage and advanced glycation in the kidney, liver, cerebellum, blood and urine of diabetic animals, as well as damage modulation for different periods of insulin treatment in order to verify that the glycaemic control in diabetic animals protects against induction of biomolecules damage. For induction of diabetes in Sprague-Dawley rats were administered 40 mg STZ per kg body weight intravenously. MDA and 5-metildC were evaluated by HPLC-DAD. The quantification of HbA1c and adducts 1,N2-&#949;dGuo, 1,N6-&#949;dAdo, 8-oxodG and CEdG was performed by HPLC-ESI-MS / MS system. The serum nitrite was determined by reading the absorbance in a spectrophotometer and the plasma creatinine concentration was determined by biochemical analyzer. The results showed that metabolic changes triggered by the condition of persistent hyperglycemia are not readily reversed after glycemic control. Blood glucose and HbA1c levels are significantly different between the groups of hyperglycemic and healthy animals, and was observed a fall in HbA1c only from insulin treatment for 6 weeks. In plasma, kidney and liver concentrations follow the profile of MDA concentration of glycated hemoglobin (HbA1c), indicating that the events of glycation and oxidative stress may be related. Glycemic control also showed beneficial effect for urine excretion of CEdG and 1,N6-&#949;dAdo despite could be seen from 8-oxodG levels that the hyperinsulinaemia leads to a frame of oxidative stress. The three lesions are generated by distinct pathways: advanced glycation, lipid peroxidation and ROS. Therefore, beyond glycaemic control, it is important to develop intervention strategies in biochemical pathways altered by the condition of hyperglycemia in order to reduce the complications risk of diabetes mellitus.

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