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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.
251

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.
252

Characterization of the Human Host Gut Microbiome with an Integrated Genomics / Proteomics Approach

Erickson, Alison Russell 01 December 2011 (has links)
The new field of ‘omics’ has spawned the development of metaproteomics, an approach that has the ability to identify and decipher the metabolic functions of a proteome derived from a microbial community that is largely uncultivable. With the development and availabilities of high throughput proteomics, high performance liquid chromatography coupled to mass spectrometry (MS) has been leading the field for metaproteomics. MS-based metaproteomics has been successful in its’ investigations of complex microbial communities from soils to the human body. Like the environment, the human body is host to a multitude of microorganisms that reside within the skin, oral cavity, vagina, and gastrointestinal tract, referred to as the human microbiome. The human microbiome is made up of trillions of bacteria that outnumber human genes by several orders of magnitude. These microbes are essential for human survival with a significant dependence on the microbes to encode and carryout metabolic functions that humans have not evolved on their own. Recently, metaproteomics has emerged as the primary technology to understand the metabolic functional signature of the human microbiome. Using a newly developed integrated approach that combines metagenomics and metaproteomics, we attempted to address the following questions: i) do humans share a core functional microbiome and ii) how do microbial communities change in response to disease. This resulted in a comprehensive identification and characterization of the metaproteome from two healthy human gut microbiomes. These analyses have resulted in an extended application to characterize how Crohn’s disease affects the functional signature of the microbiota. Contrary to measuring highly complex and representative gut metaproteomes is a less complex, controlled human-derived microbial community present in the gut of gnotobiotic mice. This human gut model system enhanced the capability to directly monitor fundamental interactions between two dominant phyla, Bacteroides and Firmicutes, in gut microbiomes colonized with two or more phylotypes. These analyses revealed membership abundance and functional differences between phylotypes when present in either a binary or 12-member consortia. This dissertation aims to characterize host microbial interactions and develop MS-based methods that can provide a better understanding of the human gut microbiota composition and function using both approaches.
253

Induktion der Eicosanoide bei Gesunden und Patienten mit Sepsis

Ludwig, Ute 04 January 2016 (has links) (PDF)
Ziel der vorliegenden Promotionsarbeit war die Untersuchung von Sepsis-assoziierten Veränderungen des Arachidonsäure (AA)-Metabolismus und die Identifikation differentiell regulierter AA-Metabolite mit Prüfung ihres diagnostischen Potentials bei Patienten mit Sepsis unter Anwendung eines in-vitro Lipopolysaccharid (LPS) Vollblutaktivierungs-Modells. In Zellüberständen von nicht-aktiviertem und LPS-aktiviertem Heparinblut (25 Sepsis- Patienten, 15 Gesunde) wurden AA-Metabolite mittels Flüssigkeitschromatographie-Tandem- Massenspektrometrie analysiert. In einer unabhängigen Kohorte (10 Sepsis-Patienten, 3 Gesunde) wurden nach RNA-Isolation aus Zellmaterial zusätzlich Target-Gene des AAMetabolismus (Cyclooxygenase (COX)-2 und mikrosomale Prostaglandin-E-Synthase (mPGES)-1 mittels quantitativer Reverse Transkriptase-Polymerase Kettenreaktion (RT-PCR) untersucht. Es konnte eine differentielle Freisetzung von AA, AA-Analoga und der COX-assoziierten Metabolite Prostaglandin (PG) E2, 11-Hydroxyeicosatetraensäure (HETE) und Thromboxan (TX) B2 zwischen Patienten und gesunden Kontrollpersonen gezeigt werden. Sepsis-Patienten wiesen dabei gegenüber Gesunden eine deutlich reduzierte Freisetzung von AA und den COXassoziierten Metaboliten 11-HETE und PGE2 auf. Das Ausmaß der reduzierten Mediatorenfreisetzung bei Sepsis-Patienten war mit der Schwere der Erkrankungssymptomatik und dem klinischen Outcome assoziiert. Auf Genexpressionsebene zeigte sich eine reduzierte Induzierbarkeit der COX-2 mRNA-Expression bei Sepsis-Patienten gegenüber Gesunden, jedoch eine erhaltene Induzierbarkeit auf der Ebene der mPGES-1.
254

Estudo de biomarcadores de mercúrio em peixes da amazônia por meio da metalômica e análise do estresse oxidativo

Bittarello, Alis Correia January 2017 (has links)
Orientador: Pedro de Magalhães Padilha / Resumo: O mercúrio é um metal tóxico, de distribuição ubíqua, com capacidade para bioacumulação e biomagnificação, que provoca alterações em biomoléculas importantes no metabolismo e contribui para o estabelecimento do estresse oxidativo em organismos aquáticos. Logo, o presente estudo teve por objetivo identificar e avaliar possíveis biomarcadores proteicos e/ou enzimáticos da toxicidade do mercúrio em peixes da região amazônica, por meio do estudo metaloproteômico e avaliação do estresse oxidativo. Foram utilizadas metodologias de fracionamento e identificação de proteínas por eletroforese bidimensional (2D PAGE) associada à espectrometria de massas (MS), mapeamento do mercúrio, em spots proteicos, por espectrometria de absorção atômica em forno de grafite (GFAAS) e avaliação de marcadores de estresse oxidativo. As espécies utilizadas foram o Plagioscion squamosissimus (corvina) e Colossoma macropomum (tambaqui), coletados na área da Usina Hidrelétrica de Jirau (rio Madeira-RO), que foram selecionadas em função da abundância populacional, interesse para a pesca e posição diferente na cadeia trófica (carnívoro e onívoro, respectivamente). Os tecidos amostrados foram o hepático, renal e muscular. Os resultados obtidos demonstraram maior concentração de mercúrio total no P. squamosissimus, espécie carnívora, e padrão de distribuição deste elemento igual para ambas as espécies (fígado>rim>músculo). Há tendência para maior atividade enzimática nos tecidos hepático e renal da espécie com... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
255

Investigation in stability of eight synthetic piperazines in human whole blood under various storage conditions over time

Lau, Timothy Wan Tsun 13 July 2017 (has links)
Over the past decade, synthetic piperazines have been associated with multiple fatalities and was one of the top 25 identified drugs in 2011. While circumventing legislative controls and preventing the detection in standard drug tests, synthetic piperazine derivatives are encountered in forensic casework as “legal” alternatives to ecstasy (3,4-methylenedioxymethamphetamine). These chemically-produced compounds share very similar pharmacological and psychological effects with ecstasy which in turn has led to their popularity as “party pills”. The long-lasting duration of synthetic piperazines, especially when 1-benzylpiperazine (BZP) is mixed with 1-(3-trifluoromethylphenyl)-piperazine (TFMPP), has also made them desirable to drug users to receive enhanced hallucinogenic effects. Although most methods are optimized to accurately quantify the amount of drugs in biological specimens submitted for forensic toxicology testing, unforeseeable challenges may arise to complicate the analysis such as postmortem redistribution, enzymatic reactions, the presence of bacterial activities, chemical and matrix interferences as well as the lack of reference materials. Thus, the purpose of this research was to investigate the stability of synthetic piperazines in human whole blood under various storage conditions and time ranges. A total of eight synthetic piperazines were assessed on their degrees of degradation using a Shimadzu Ultra-Fast Liquid Chromatography (UFLC) with SCIEX 4000 Q-Trap Electrospray Ionization Tandem Mass Spectrometry in positive ionization mode. These analytes included: 1-benzylpiperazine (BZP), 1-(4-fluorobenzyl)-piperazine (FBZP), 1-(4-methylbenzyl)-piperazine (MBZP), 1-(4-methoxyphenyl)-piperazine (MeOPP), 1-(para-fluorophenyl)-piperazine (pFPP), 1-(3-chlorophenyl)-piperazine (mCPP), 2,3-dichlorophenylpiperazine (DCPP), and 1-(3-trifluoromethylphenyl)-piperazine (TFMPP). Individual unknown samples were prepared by spiking certified reference standards (Cayman Chemical, Ann Arbor, MI, U.S.A.) of each synthetic piperazine into certified drug-free human whole blood (UTAK Laboratories, Inc., Valencia, CA, U.S.A.) independently at 1000 ng/mL. To closely monitor the stability of each compound and potential drug-drug interactions, mixed samples consisted of all eight piperazines were also stored at room temperature (~20°C), 4°C and -20°C for one, three, six, nine and twelve months in dark sealed containers. Solid phase extraction (SPE) was performed to remove unwanted components prior to the injection into the LC system. Drug of Abuse (DAU) mixed-mode copolymeric columns (Clean Screen®, UCT Inc., Levittown, PA, U.S.A.) were utilized with a positive pressure manifold rack followed by evaporating to dryness with low heat at 65°C. All samples were then reconstituted with 250 µL of 50:50 mixture of methanol and 2mM ammonium formate buffer with 0.2% formic acid (Fisher Scientific, Waltham, MA, U.S.A.). Analysis was performed in triplicate using a reversed-phase column (Kinetex® F5, Phenomenex®, Torrance, CA, U.S.A.) with a binary gradient of a 2mM ammonium formate buffer with 0.2% formic acid and methanol with 0.1% formic acid. The total run time was 11.5 minutes including equilibration and the flow rate was 0.4 mL/min. Three internal standards including BZP-d7, mCPP-d8 and TFMPP-d4 (Cerilliant, Round Rock, TX, U.S.A) were used to generate calibration curves that were ranged from 20 ng/mL to 2000 ng/mL. Results revealed that BZP, MBZP and FBZP were more stable than phenyl piperazines over time under all storage conditions, in which MBZP was consistently more stable and still had more than 70% remaining after 12 months. Data showed a smaller degree of degradation when samples were kept frozen or refrigerated; whereas storing at room temperature should be avoided to ensure minimal degradation and detrimental impacts on stability of piperazine compounds. For crime laboratories that are facing backlog situations, case samples with synthetic piperazines should be kept frozen or refrigerated even for time period as short as 30 days or less. However, storing them for too long will clearly affect the quantitation accuracy because phenyl piperazines are more susceptible to degrade completely after six months regardless of storage conditions. Additionally, matrix interference was present due to the outlier of MBZP quantified on Day 270. Drug-drug interaction was also observed in the analyte mixture but the exact stability pattern of phenyl piperazines when mixed together could not be determined from this data set alone due to discrepancies observed on Day 91 and 270. This research project had shown a solid method to examine how quickly or slowly synthetic piperazines degrade in blood at different storage conditions. To further this study, it would be also important to evaluate the number of freeze-thaw cycles on each specimen in order to minimize the effect of non-metabolic degradation.
256

Análise comparativa de parâmetros bioquímicos e fisiológicos de um genótipo de feijão-de-corda (Vigna unguiculata L. Walp.) suscetível e seu mutante derivado, resistente, infectados com o vírus do mosaico severo do caupi (CPSMV) / Comparative Analysis of Physiological and Biochemical Parameters from a Susceptible Cowpea (Vigna unguiculata L. Walp.) genotype and its derivative mutagenized-Resistant both infected with Cowpea Severe Mosaic Virus

Souza, Pedro Filho Noronha de January 2016 (has links)
SOUZA, Pedro Filho Noronha de. Análise comparativa de parâmetros bioquímicos e fisiológicos de um genótipo de feijão-de-corda (Vigna unguiculata L. Walp.) suscetível e seu mutante derivado, resistente, infectados com o vírus do mosaico severo do caupi (CPSMV). 2016. 180 f. Tese (Doutorado em bioquímica)- Universidade Federal do Ceará, Fortaleza-CE, 2016. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-28T15:30:39Z No. of bitstreams: 1 2016_tese_pfnsouza.pdf: 6363124 bytes, checksum: a74bcc0c69df39e0286b864e93babb1a (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-08-02T14:43:45Z (GMT) No. of bitstreams: 1 2016_tese_pfnsouza.pdf: 6363124 bytes, checksum: a74bcc0c69df39e0286b864e93babb1a (MD5) / Made available in DSpace on 2016-08-02T14:43:45Z (GMT). No. of bitstreams: 1 2016_tese_pfnsouza.pdf: 6363124 bytes, checksum: a74bcc0c69df39e0286b864e93babb1a (MD5) Previous issue date: 2016 / Cowpea is an important crop that makes major nutritional contributions as a source of proteins and carbohydrates in the diet of many people worldwide. However, its production is impaired due to various stresses including those of biotic origins. Cowpea Severe Mosaic Virus (CPSMV) infects cowpeas leading to severe symptoms and low productivity. Several studies of plant-virus interaction show that seed treatment with Ethyl methanesulfonate (EMS, chemical mutagen), results in a resistant phenotype in plants, which was previously susceptibility, to virus infection of the Potyvirus genus. The aim of this study was to investigate some physiological and biochemical parameters of a susceptible cowpea cultivar (CPI) (CE-31, sin. Pitiuba) in comparison with its derived resistant mutagenized (MCPI), both infected with CPSMV. MCPI plantlets were obtained after treatment of CE-31 seeds with 0.04% EMS. Two different approaches were used in this study: 1) biochemical (antioxidant enzymes and H2O2 content, PR-proteins and secondary metabolites) and physiological analysis (photosynthetic parameters and chlorophyll content); and 2) Label free quantitative proteomic approach (LC-ESI-MS / MS) to identify proteins responsive to viral infection. Our results showed that MCPI had no symptoms of CPSMV infection and biochemical (high H2O2, PR-proteins and secondary compounds [phenolic and lignin]) and physiological responses (High photosynthesis index and chlorophyll content) is activated in MCPI plantlets after CPSMV inoculation. With regard to proteomic analysis, 99 proteins were differentially represented, where these 68 are up- and 31 down represented in MCPI compared to CPI. Regardless whether to CPI (susceptible) or MCPI (mutagenized resistant) plantlets, CPSMV induce changes in proteome profile that involve several biological process (energy and metabolism, photosynthesis, response to stress, oxidative burst, and scavenging). Moreover, these results suggest that the CPSMV responsive proteins in the MCPI represent a complex network involving in resistant mechanisms to CPSMV. Treatment of the susceptible CE-31 genotype seeds with the mutagenic agent EMS induced genomic alterations generating a cowpea mutagenized resistant to CPSMV by apparently inducing classical biochemical and physiological responses against infection. / O feijão-de-corda tem grande importância socioeconômica no Nordeste brasileiro. Entretanto, sua produção é baixa devido a diversos fatores bióticos, como, por exemplo, o vírus do mosaico severo do caupí (CPSMV, gênero Comovirus), que apresenta grande destaque, por causar a virose que mais acomete essa cultura no país. No estudo da interação planta-vírus, diversos trabalhos mostram que o tratamento de sementes com o etil metanosulfonato (EMS, mutagênico químico) resulta no fenótipo de resistência em plantas que, anteriormente, apresentavam susceptibilidade à infecção por vírus do gênero Potyvirus. Por essa razão, o presente estudo teve como objetivo investigar as respostas de defesa bioquímicas e fisiológicas das plantas de feijão-de-corda do genótipo (CE-31) susceptível ao CPSMV (CPI) a partir de sementes tratadas com EMS (0,04% v/v), e avaliar se as plantas mutagenizadas (MCPI), produzidas a partir dessas sementes se tornaram resistentes ao CPSMV. Duas diferentes abordagens foram utilizadas neste trabalho: 1) análises bioquímicas (enzimas antioxidantes e conteúdo de H2O2, PR-proteínas e compostos secundários) e fisiológicas (parâmetros fotossintéticos e teor de clorofila); 2) abordagem proteômica quantitativa (LC-ESI-MS/MS), livre de marcação, para identificar proteínas responsivas à infecção viral. Os resultados obtidos demonstram que as plantas MCPI são capazes de induzir respostas bioquímicas (aumento de H2O2, indução de PR-proteínas e aumento no conteúdo de compostos secundários) e alterações nos parâmetros fisiológicos (alta taxa fotossintética e teor de clorofila) que, aparentemente, têm relação com o fenótipo de resistência das plantas mutagenizadas ao CPSMV. Na análise proteômica, 99 proteínas foram identificadas como sendo diferenciais, das quais 68 aumentaram e 31 diminuíram em abundância nas plantas MCPI em relação as plantas CPI. A análise proteômica, mostrou diversas vias metabólicas (Metabolismo Redox, Energia e Metabolismo, Fotossíntese, Metabolismo de RNA e Defesa) envolvidas nas respostas de defesa das plantas MCPI frente a infecção viral. O tratamento das sementes com o EMS, resultou em plantas de feijão-de-corda com fenótipo de resistência capazes de acionar mecanismos de defesa para impedir a infeção viral.
257

Contaminação de agrotóxicos na água para consumo humano no RS : avaliação de riscos, desenvolvimento e validação de método empregando SPE e LC-MS/MS

Zini, Luciano Barros January 2016 (has links)
Os agrotóxicos, quando presentes na água, são definidos como micropoluentes: mesmo em baixas concentrações, conferem à água características de toxicidade. Aponta-se o RS como o quarto estado do Brasil com maior volume de vendas anuais de agrotóxicos, chegando a mais de 50 mil toneladas por ano. Desde 2014 está em vigência no território gaúcho uma portaria estadual que acrescenta a exigência de 46 parâmetros de agrotóxicos no padrão de potabilidade da água, além dos 27 já exigidos pela portaria nacional. Neste trabalho, 89 pesticidas foram avaliados conforme três métodos teóricos de predição de risco de contaminação em mananciais subterrâneos e superficiais: índice Ground Ubiquity Score (GUS), método Screening da USEPA e método de GOSS, baseados nas propriedades físico-químicas dos pesticidas. Nos anos de 2015 e 2016, foram realizadas 143 coletas de água para consumo humano em 45 municípios da bacia hidrográfica do Alto Jacuí (G-50), a que possui a maior taxa de aplicação de agrotóxicos do estado, para análises de vigilância através de laboratório contratado, envolvendo os 89 pesticidas presentes na portaria nacional e estadual. Em paralelo, 183 pesticidas presentes em uma solução-padrão foram empregados no desenvolvimento de um novo método de análise multiresíduos, com etapas de pré-tratamento por filtração seguidas por extração em fase sólida e LC-MS/MS, aplicada para os três maiores municípios da G-50 (Carazinho, Soledade e Cruz Alta) em amostras de água bruta e tratada, durante quatro períodos de aplicação de agrotóxicos dos principais cultivos agrícolas da região. Dos pesticidas mencionados nas portarias nacional e estadual, 12 foram classificados com o maior risco de contaminação tanto em água superficial e subterrânea de acordo com os três métodos teóricos empregadas. Nas análises de vigilância foi detectado permetrina em Carazinho e alaclor em Espumoso. No método desenvolvido, 75 pesticidas foram validados de acordo com os critérios propostos e atingiram limites de detecção (LD) e limites de quantificação (LQ) que variaram de 10 a 300 ng L-1. Na aplicação do método nas coletas dos três municípios da G-50 não houve detecção de nenhum pesticida. / Agrochemicals, when present in water, are defined as micropollutants, thus giving the water toxic characteristics, even at low concentrations. The Rio Grande do Sul state in Brazil was found to rank fourth in annual agrochemical sales in the country, surpassing 50 thousand tons per year. A state regulation in effect in the RS state since 2014 requires the inclusion of 46 new agrochemical parameters concerning the standards for potable drinking water, in addition to 27 existing parameters mandated by national ordinance. Seventy-five pesticides were evaluated based on three theoretical methodologies of contamination risk prediction in underground and surface water sources, by measuring the physicochemical properties of pesticides: GUS index, USEPA screening method and Goss method. In 2015 and 2016, 143 water samples were collected from sources of potable water in 45 municipalities located in the Alto Jacuí river basin, a region which has the highest pesticide application rate in the RS state. A private laboratory analyzed samples from 89 pesticides present in the national and state regulation. Paralely, 183 pesticides were evaluated by a new multi-residue analysis method. Filtration was conducted in the pre-treatment steps, followed by a solid phase extraction liquid chromatography coupled with mass spectrometry analysis (SPE-LC-MS/MS) of raw and treated water samples from the three largest G-50 municipalities (Carazinho, Soledade and Cruz Alta), during the four pesticide application periods of the main crops cultivated in the region. Twelve pesticides were classified as of high risk in terms of contamination for both surface and groundwater, in accordance with the three theoretical methodologies implemented. During analysis of the surveillance data collected, the pesticides permethrin and alachlor were found in Carazinho and Espumoso, respectively. Through the methodology developed, 75 pesticides were evaluated according to the criteria proposed, reaching lower detection limit (LD) and quantification limit (LQ) ranging from 10 to 300 ng L-1, respectively. During the implementation of the methodology for sample collections in the three G-50 municipalities, no pesticides were detected.
258

Desenvolvimento e validação de métodos analíticos e estudos de estabilidade da rivaroxabana

Wingert, Nathalie Ribeiro January 2015 (has links)
A análise de fármacos é fundamental nas diversas fases do desenvolvimento farmacêutico, tais como estudos de formulação, estabilidade e controle de qualidade do produto. A rivaroxabana (RIV) é um anticoagulante de uso oral indicado para prevenção da formação de coágulos venosos. A literatura pesquisada apresenta poucos relatos de determinação quantitativa e de estudos de estabilidade do fármaco em comprimidos. E ainda nenhum método analítico em compêndios oficiais Diante do exposto, o objetivo deste trabalho foi desenvolver e validar métodos analíticos para determinação qualitativa e quantitativa da RIV por cromatografia líquida de alta eficiência com detecção por UV e de ultra eficiência com detecção por espectrometria de massas (CLAE-UV e CLUE-EM) e eletroforese capilar (EC). Os resultados encontrados foram adequados conforme o preconizado nos guias oficiais nacionais e internacionais. Foi avaliada também a viabilidade da técnica de eletroforese capilar em microchip para análise de RIV. Através de método desenvolvido por CLAE foi realizado estudo de cinética de degradação e posterior avaliação do potencial tóxico in vitro das amostras de degradação forçada da RIV. A identificação de três produtos de degradação majoritários da RIV, formados a partir de estresse ácido, alcalino e fotolítico, foi realizada por CLUE-EM/EM, possibilitando a proposição da estrutura molecular de cada produto de degradação. O potencial tóxico da RIV antes e depois da exposição à degradação forçada foi avaliado através dos métodos in vitro MTT, Vermelho Neutro, Ensaio Cometa e DNA de baixo peso molecular. Não foram encontrados sinais de dano ao DNA celular, contudo, amostras de RIV expostas ao meio alcalino apresentaram maior redução da viabilidade celular. O trabalho avaliou ainda o perfil de dissolução da RIV em comprimidos baseado nos dados de absorção in vitro conforme modelagem in silico dos dados, estabelecendo uma correlação linear entre a fração absorvida e fração dissolvida. As diferentes metodologias e técnicas desenvolvidas e aplicadas nesse trabalho contribuem para o desenvolvimento do controle de qualidade farmacêutico na direção de ensaios mais confiáveis que garantam a segurança e eficácia de medicamentos. / Drug analysis is critical at various stages of pharmaceutical development, such as formulation studies, stability and quality control products. Rivaroxaban (RIV) is an oral anticoagulant indicated for prevention of thromboembolism. Literature contains few reports of quantitative determination and drug stability studies of RIV on pharmaceutical formulation. Analytical method for RIV quality control are not evaluable on official guides yet. This research work aimed to develop and validate analytical methods for qualitative and quantitative determination of RIV by high and ultra performance liquid chromatography with UV detection mass spectrometry detection (HPLC -UV and UPLC-MS) and capillary electrophoresis (CE). The results were adequate as recommended in national and international official guides. Reliability of RIV analysis by microchip capillary electrophoresis was also assessed. Through the method developed by HPLC degradation kinetic studies were performed, zero order kinetic has better description of RIV degradation behaviour. RIV toxic potential before and after exposure to forced degradation was assessed by in vitro methods of MTT, Neutral Red, Comet Assay, and Low Molecular Weight DNA. There were no signals of DNA damage however, RIV samples exposed to alkaline medium showed increased reduction in cell viability. Identification of RIV degradation products formed after exposure to acid and alkaline media and UVC radiation was performed by UPLC-MS / MS. It was possible to elucidate molecular structures of three major degradation products. This study also assessed the dissolution profile of RIV tablets based on in vitro absorption data, a linear point-to-point correlation was found for fraction absorbed and dissolved. Different methodologies and techniques developed and applied in this work can contribute to the development of pharmaceutical quality towards more reliable tests to ensure safety and efficacy of medicines.
259

Identificação e Caracterização de metabólitos de sulfaquinoxalina

Hoff, Rodrigo Barcellos January 2014 (has links)
A presença de resíduos de medicamentos antibacterianos em alimentos é um importante problema de saúde pública. Estas substâncias podem estar presentes nos alimentos em níveis inaceitáveis como resultados de práticas produtivas inadequadas. Devido a estas preocupações, são estabelecidos limites máximos de resíduos para estas substâncias (LMRs). No caso das sulfonamidas, este valor de LMR refere-se à soma do princípio ativo e de todos seus metabólitos. Neste trabalho, identificam-se e caracterizam-se metabólitos de sulfaquinoxalina (SQX) em diversas espécies animais. Dentro do processo investigativo, foram realizados estudos comparativos de métodos de extração, processos de validação e determinação de efeito de matriz. Foi elaborado e proposto um modelo para a priorização de fármacos baseado em análise de risco e discutiu-se o panorama atual da presença de resíduos de sulfonamidas em amostras ambientais. A investigação da formação de metabólitos de SQX in vitro e in vivo levaram à identificação de três compostos, dois deles ainda não descritos na literatura: N4-acetil-SQX, SQX-OH e N4-acetil-SQX-OH. O perfil de formação destes compostos em diversas espécies animais foi analisado e discutido. / The presence of antibacterial drugs residues in food is an important public health issue. These substances can be present in food at unacceptable levels due to inappropriate veterinary practices. Because of that, maximum residue levels (MRL) are established for these compounds. In the sulfonamide drugs case, this value corresponds to the sum of parent drug and their metabolites. In the present work, sulfaquinoxaline (SQX) metabolites were identified and characterized in several animal species. Inside that investigation process, several studies were developed about extraction methods, validation processes and matrix effects determination. A model for drugs residues prioritization based on risk analysis was proposed. Also, the state-of-art of sulfonamides residues analysis in environmental samples was discussed. The in vivo and in vitro investigation of SQX metabolites formation lead us to the identification of 3 compounds, 2 of them previously unreported: N4-acetyl-SQX, SQX-OH and N4-acetyl-SQX-OH. The formation profile of these compounds in several animal species was analyzed and discussed.
260

Expressão gênica diferencial e análise protéica do leite de búfalas sadias e com mastite subclínica / Differential gene expression and analysis of milk proteins from dairy buffalo with and without subclinical mastitis

Tanamati, Fernanda 27 February 2018 (has links)
Submitted by FERNANDA TANAMATI null (fertanamati@gmail.com) on 2018-03-22T00:14:15Z No. of bitstreams: 1 Tese_Tanamati_versão final.pdf: 1118298 bytes, checksum: ad444e697e657dd704d25b099b8eeede (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-03-22T10:54:04Z (GMT) No. of bitstreams: 1 tanamati_f_dr_jabo.pdf: 1118298 bytes, checksum: ad444e697e657dd704d25b099b8eeede (MD5) / Made available in DSpace on 2018-03-22T10:54:04Z (GMT). No. of bitstreams: 1 tanamati_f_dr_jabo.pdf: 1118298 bytes, checksum: ad444e697e657dd704d25b099b8eeede (MD5) Previous issue date: 2018-02-27 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A mastite em búfalas leiteiras causa perdas econômicas devido à diminuição da produção de leite, além de ter um efeito negativo no bem-estar dos animais. Deste modo, foram realizados dois estudos: o objetivo do estudo I foi avaliar o nível de expressão dos genes da lactoferrina (LTF), fator de necrose tumoral alfa (TNF-α), interleucina-1 beta (IL-1β), interleucina-8 (IL-8), e toll-like receptors 2 (TLR-2) e 4 (TLR-4) em búfalas Murrah com e sem mastite subclínica. Amostras de leite de 12 búfalas com mastite e 12 de búfalas sem mastite foram coletadas, para a extração de RNA, síntese de cDNA e validação dos perfis de expressão por qRT-PCR. O ΔΔCt foi estimado utilizando contrastes ortogonais da expressão dos genes alvo corrigidos para a expressão dos genes housekeeping entre os tratamentos. A expressão dos genes TLR-2, TLR-4, TNF-α, IL-1β e IL-8 foi regulada positivamente em búfalos com mastite, enquanto que o gene LTF não apresentou expressão diferencial. O estudo desses genes da função imune que são ativos na glândula mamária é importante para o desenvolvimento de estratégias destinadas a preservar a saúde do úbere. O objetivo do estudo II foi avaliar as proteínas presentes no soro do leite de búfalas com e sem mastite subclínica, utilizando uma abordagem proteômica para identificar proteínas diferencialmente expressas e potencial biomarcador para a doença. Para isso, 16 amostras de leite de búfalas Murrah foram coletadas, sendo oito animais com e oito animais sem mastite subclínica. O método contagem espectral foi utilizado para quantificar a abundância relativa das proteínas individuais e os bancos de dados de proteínas anotadas para Bubalus bubalis e para Bos taurus foram utilizados na análise. Após integração das anotações genéticas das referências de búfalos e bovinos, foram identificadas 1.033 proteínas, das quais 156 proteínas foram diferencialmente reguladas entre animais sadios e infectados. Foram identificados 18 processos biológicos nos quais essas proteínas participam e a catelicidina-3 foi identificada como um potencial biomarcador da mastite subclínica. Os resultados são importantes para compreender melhor o comportamento da mastite na glândula mamária das búfalas e, portanto, podem auxiliar no diagnóstico precoce da doença. / Mastitis in dairy buffalo causes economic losses due to decreased milk production, along with having a negative effect on the animals’ welfare. Thus, two studies were performed: the objective of study I was to evaluate the expression levels of lactoferrin (LTF), tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin- 8 (IL-8) and toll-like receptors 2 (TLR-2) and 4 (TLR-4) in Murrah buffaloes with and without subclinical mastitis. Milk samples were collected from 12 buffaloes with mastitis and 12 buffaloes without mastitis for RNA extraction, cDNA synthesis, and validation of expression profiles by qRT-PCR. The ΔΔCt was estimated using orthogonal contrasts of the target genes expression adjusted for the expression of the housekeeping genes between both treatments. The expression of the TLR-2, TLR-4, TNF-α, IL-1β and IL-8 genes were upregulated in buffaloes with mastitis, while the LTF gene showed no differential expression. The study of these immune function genes that are active in the mammary gland is important for the development of strategies aimed at preserving the health of the udder. The objective of study II was to evaluate the proteins present in the milk whey from buffaloes with and without subclinical mastitis, using a proteomic approach to identify differentially expressed proteins and potential biomarkers for the disease. For this, 16 samples of Murrah buffalo milk were collected, comprised of eight animals with and eight animals without subclinical mastitis. The spectral counting method was used to quantify the relative abundance of the individual proteins, and the databases of proteins annotated for Bubalus bubalis and for Bos taurus were used in the analysis. After integrating the gene annotations from the buffalo and bovine references, a total of 1,033 proteins were identified, of which 156 proteins were differentially regulated between healthy and affected animals. 18 biological processes in which these proteins participate were identified, and cathelicidin-3 was identified as a potential biomarker of subclinical mastitis. These results are important to better understand the behavior of mastitis in the buffalo mammary gland, and in turn may aid in the early diagnosis. / FAPESP: 14/19321-4 / FAPESP: 14/25309-7 / FAPESP: 16/10526-8

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