Submitted by JEFFERSON HONORIO FRANCO null (jeffersonhfranco@gmail.com) on 2016-12-01T15:16:17Z No. of bitstreams: 1 TESE FINAL-IMPRESSÃO CD.pdf: 4568825 bytes, checksum: 666b30b163102c69eb93110502678419 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-05T12:50:59Z (GMT) No. of bitstreams: 1 franco_jh_dr_araiq_par.pdf: 1149871 bytes, checksum: 4c942fc016c94499d690f6474dda7078 (MD5) / Made available in DSpace on 2016-12-05T12:50:59Z (GMT). No. of bitstreams: 1 franco_jh_dr_araiq_par.pdf: 1149871 bytes, checksum: 4c942fc016c94499d690f6474dda7078 (MD5) Previous issue date: 2016-11-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Corantes sintéticos do tipo azo têm sido um assunto de grande preocupação ambiental devido ao potencial genotóxico e mutagênico dos produtos de biotransformação. Deste modo, nos últimos anos a consequência da ingestão destes corantes presentes na agua potável servida à população é discutida por diversos autores. Este estudo avalia a ação de microssomas de fígado de rato, enzimas redutoras produzidas pela bactéria Escherichia coli (E. coli) e nitroredutase imobilizada na biotransformação de três corantes dispersos que possuem grupos azo, Disperse Red 73 (DR 73), Disperse Red 78 (DR 78) e Disperse Red 167 (DR 167). A técnica de Espectrofotometria de absorção molecular na região do Uv- visível, Cromatografia Líquida de Alta Eficiência com detector de arranjo de diodos (CLAE-DAD) e Cromatografia líquida acoplada à espectrometria de massas (LC-MS/MS) foram técnicas usadas para identificar os principais produtos gerados após os processos de degradação dos corantes. Polímeros de impressão molecular magnéticos (MMIPs) foram investigados usando reações de polimerização por precipitação para pré-concentração do corante DR 73, juntamente com a degradação por fotoeletrocatálise e subsequente análise dos produtos por LC-MS/MS. Os estudos in vitro do metabolismo de biotransformação dos corantes têxteis com microssoma de fígado de rato mostraram que as reações ocorreram preferencialmente no grupo azo e nitro dos corantes, indicando a redução destes grupos pelas enzimas do citocromo P-450. Foram obtidos dois produtos de degradação para cada corante após reação com a bactéria E. coli; o corante DR 73 originou os produtos 3-((4-aminofenil)(etil)amino)propanitrila e 4-nitroanilina, os produtos 3-((4-aminofenil)(etil)amino)propanitrila e 2-cloro-4-nitroanilina foram obtidos após reação com o corante DR78 e o DR 167 originou dimetil 3,3`-((3-acetamido-4aminofenil)azanediyl)dipropanoato e 2-cloro-4-nitroanilina, indicando a clivagem do grupo azo, possivelmente, pela enzima azoredutase, produzida pela bacteria. A enzima nitroredutase, imobilizada em partículas magnéticas modificadas com tosil, mostrou que a redução dos corantes ocorreu preferencialmente no grupo nitro, enquanto que a enzima livre no meio reacional resultou em mais de um produto de biotransformação para cada corante, atuando em mais de um sítio da molécula, comprovando a eficácia da imobilização enzimática para estudos de biotransformação e formação de produtos majoritários. A mutagenicidade dos corantes foi avaliado pelo ensaio de Salmonella/microssoma realizado nas estirpes TA 98 e TA 100, com e sem S9. De acordo com este ensaio, DR 73 foi o mais mutagênico. O MMIP para o corante DR 73 apresentou excelentes valores de religação (16 mg g−1 e 6 mg g−1, para MMIP e MNIP, respectivamente) indicando que o polímero molecularmente impresso formou cavidades específicas para retenção do corante. Através dos resultados obtidos por LCMS/MS, observou-se 100% de degradação do corante em apenas 60 min de tratamento via fotoeletrocatálise para soluções mais diluidas do mesmo, comprovando a eficiência da técnica na degradação de poluentes. Sendo assim, estes resultados sugerem que o MMIP mostrou uma excelente especificidade e seletividade para o corante DR 73 e uma técnica promissora na captação de corantes mutagênicos de águas superficiais, com grande potencial de aplicação e exploração na pré-concentração antes do tratamento. Além disso, a redução destes corantes por sistemas biológicos representa uma grande preocupação ambiental devido ao aumento da genotoxicidade para os seres vivos, em especial a seres humanos, produzindo compostos nocivos, tais como aminas condenadas pela Agência Internacional de Pesquisa sobre o Câncer. / Synthetic azo dyes have been a matter of great concern due to the genotoxic and mutagenic potential of the products originating from azo dye biotransformation. Thus, in recent years the result of the intake of these dyes present in drinking water supplied to a population is discussed by several authors. This work evaluates the action of rat liver microsomes, reducing enzymes produced by the Escherichia coli (E. coli) and nitroreductase immobilized on biotransformation of three disperse dyes bearing azo groups, namely Disperse Red 73 (DR 73), Disperse Red 78 (DR 78), and Disperse Red 167 (DR 167). UV-Vis spectrophotometry, high-performance liquid chromatography with diode array detector (HPLC-DAD), and liquid chromatography coupled to mass spectrometry (LC-MS/MS) were techniques used to identify the main products generated after the process degradation of dyes. Magnetic molecularly imprinted polymers (MMIPs) were investigated using precipitation polymerization reactions for preconcentration of the dye DR 73, together with the photoelectrocatalysis degradation and subsequent analysis of the products by LC-MS/MS. In vitro studies of biotransformation metabolism of textile dyes with rat liver microsome showed that the reactions occur preferentially in the group of azo and nitro dyes, indicating the reduction of these groups by enzymes of the cytochrome P-450. There were obtained two degradation products for each dye after reaction with E. coli; the dye DR 73 gave the product 3 - ((4-aminophenyl) (ethyl) amino) propanitrila and 4-nitroaniline, the product 3 - ((4-aminophenyl) (ethyl) amino) propanitrila and 2-chloro-4-nitroaniline were obtained after reaction with the dye DR78 and DR 167 gave 3,3`-dimethyl-((3-acetamido-4-aminophenyl) azanediyl) dipropanoato and 2chloro-4-nitroaniline; indicating cleavage of the azo group, possibly by azoredutase enzyme produced by bacteria. The nitroreductase enzyme immobilized on modified magnetic particles Tosyl showed that the reduction of dyes occurred preferentially in the nitro group, while the free enzyme in the reaction medium resulted in more than a product of biotransformation for each dye, acting in more than one site of the molecule, proving the efficacy of enzyme immobilization for biotransformation studies and formation of major products. The mutagenicity of the dyes was evaluated by the Salmonella/microsome assay performed on strains TA 98 and TA 100, with and without S9. According to this assay, DR 73 was the most mutagenic. The MMIP to the dye DR 73 showed excellent rebinding values (16 mg g−1 and 6 mg g−1, for MMIP and MNIP, respectively) indicating that the molecularly imprinted polymer formed cavities for specific dye retention. Through the results obtained by LC-MS/MS, it was observed 100% dye degradation in 60 min treatment for more dilute solutions thereof, proving the efficiency of technique in pollutant degradation. Thus, these results suggest that MMIP showed excellent specificity and selectivity for the dye DR 73 and a promising technique in capturing mutagenic dyes of surface water, with great potential for application and operation in the pre-concentration before treatment. Moreover, the reduction of these dyes by biological systems is a major environmental concern due to increased of genotoxicity for living beings, especially humans, producing harmful compounds, such as condemned amines by the International Agency for Research on Cancer.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Bottled mineral water is a widely consumed product in Brazil because it is considered a reliable source of drinking water. On the other hand, there is the great use of pesticides, which can reach and contaminate groundwater, the main source of mineral water. The present research had the objective of developing a method for the determination of residues of pesticides in bottled mineral water, using the technique of solid phase extraction with alternative adsorbent to the base of graphene oxide and liquid chromatography/mass spectrometry. For that, tests were performed to optimize the instrumental and extraction conditions for the analysis of 6 pesticides (alachlor, atrazine, carbaryl, carbofuran, pyrimicarb and endosulfan sulfate). The analytes were extracted with graphene oxide and a mixture of methanol and acetonitrile, presenting satisfactory recovery values (76 ± 1.6 and 100 ± 2.4%) in a concentration range of 0.5 to 2.5 μg L-1. In optimal conditions good linearity and sensitivity were obtained in a range of 1 to 1000 μg L-1 with determination coefficients above 0.99. The relative standard deviations for triplicate determinations were less than 12% and the limits of detection and quantification were in the range of 0.0003-0.017 μg L-1 0.001-0.05 μg L-1, respectively. The proposed method was applied in the determination of pesticides residues in bottled mineral water produced in Sergipe. / A água mineral engarrafada é um produto largamente consumido no Brasil por ser considerada fonte confiável de água potável. Em contrapartida, há o grande uso de agrotóxicos, que podem atingir e contaminar águas subterrâneas, principal fonte de água mineral. O presente trabalho tem como objetivo desenvolver um método para determinação de resíduos de agrotóxicos em água mineral engarrafada, utilizando a técnica de extração em fase sólida com adsorvente alternativo a base de óxido de grafeno e cromatografia líquidaespectrometria de massas. Para tanto, foram realizados testes para otimizar as condições instrumentais e de extração para análise de 6 agrotóxicos (alacloro atrazina, carbaril, carbofurano, pirimicarbe e sulfato de endosulfam). Os analitos foram extraídos com óxido de grafeno e uma mistura de metanol e acetonitrila, apresentando valores de recuperação satisfatórios (76±1,6 e 100±2,4%) em um intervalo de concentração 0,5 a 2,5 μg L-1. Sob condições ótimas foi obtida boa linearidade e sensibilidade em um intervalo de 1 a 1000 μg L-1 com coeficientes de determinação superiores a 0,99. Os desvios padrão relativos para determinações em triplicata foram inferiores a 12% e os limites de detecção e quantificação ficaram no intervalo de 0,0003–0,017 μg L-1 0,001–0,05 μg L-1, respectivamente. O método proposto foi aplicado na determinação de resíduos de agrotóxicos em água mineral engarrafada produzida em Sergipe. / São Cristóvão, SE

Orientador: Isabel Cristina Sales Fontes Jardim / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-13T14:12:56Z (GMT). No. of bitstreams: 1 Chiaradia_MarizaCampagnolli_D.pdf: 1242763 bytes, checksum: 4ac5b4a27010b8220c940b8c68bc5922 (MD5) Previous issue date: 2009 / Resumo: O Brasil é o maior produtor mundial de citrus e o principal exportador de suco. Dentre as espécies cultivadas no Brasil, há a predominância de laranjas Pera e tangerinas Murcote. Porém, os agricultores brasileiros tem enfrentado a incidência de várias pragas agrícolas na cultura de citrus, de forma que, para manter a produção e a qualidade, tem sido necessário aplicar agrotóxicos de forma constante e cada vez maior. Por outro lado, devido ao risco resultante da exposição dos consumidores aos resíduos de agrotóxicos presentes nos alimentos, agencias governamentais reguladoras tem estabelecido limites máximos de resíduos (LMR) para todos os agrotóxicos. Neste contexto, três métodos para a determinação de resíduos dos principais agrotóxicos (aldicarbe, difenoconazol, diflubenzurom, diurom, imidacloprido e tiofanato metílico) aplicados no cultivo de laranjas Pera e tangerinas Murcote foram desenvolvidos e validados. Vários métodos de preparo de amostras foram avaliados e o método QuEChERS foi o que se mostrou mais eficiente, rápido e simples. Foram utilizadas diferentes técnicas cromatográficas para a validação do método: cromatografia líquida de alta eficiência com detecção por arranjo de diodos (CLAE-DAD), cromatografia líquida acoplada a espectrometria de massas em série (CL-EM-EM) e cromatografia líquida de ultra eficiência com detecção por arranjo de diodos (CLUE-DAD). Os parâmetros analíticos mostraram que o método proposto extrai de maneira satisfatória os agrotóxicos das matrizes, permitindo sua detecção por todas as técnicas analíticas utilizadas. Entretanto, devido a complexidade da matriz estudada foi necessário fazer a calibração na matriz. As recuperações obtidas foram de 79 a 124% com CLAE-DAD, de 83 a 119% com CL-EM-EM e de 78 a 113% com CLUEDAD, com coeficientes de variação menores que 15% para todas as tecnicas cromatograficas. Os limites de quantificacao obtidos mostraram que os métodos podem ser utilizados para a detecção dos agrotóxicos em concentrações abaixo dos LMR estabelecidos pela legislação brasileira e dos EUA. Com a CLUE-DAD obtiveram-se os menores tempos de análise, 7 min, e a CL-EM-EM foi a técnica cromatografica mais seletiva e com a melhor detectabilidade (4 mg L) utilizada neste trabalho. O método foi aplicado a amostras coletadas no comercio da cidade de Campinas-SP e o agrotóxico encontrado com maior frequência foi o imidacloprido, mas em concentrações abaixo dos LMR / Abstract: Brazil is the world's largest producer of oranges and the largest exporter of juice. Among the species grown in Brazil, there is a predominance of Pera oranges and Murcote tangerines. Brazilian agriculturist have faced several diseases during orange and tangerine cultivation that demand constant and even expensive applications of pesticides to mantain production and quality. On the other hand, because of potential health risk to the consumers, resulting from acute and/or chronic dietary exposure, government regulatory agencies have established maximum residue limits (MLR) for all the pesticides. Thus, this work developed and validated three methods to determine the main pesticides applied to Pera orange and Murcote tangerine cultivation in Brazil: aldicarb, difenoconazole, diflubenzuron, diuron, imidacloprid and thiophanate-methyl. Several sample preparation methods were evaluated and the QuEChERS method was the more suitable, rapid and simplest extraction method for the matrices studied. The methods were validated using different chromatographic techniques: high performance liquid chromatography ¿ diode array detection (HPLC-DAD), liquid chromatography ¿ tandem mass spectrometry (LC-MSMS) and ultra-performance liquid chromatography ¿ diode array detection (UPLC-DAD). The analytical parameters demonstrate that the proposed methodologies satisfactorily extract the pesticides from the matrices, allowing detection using all the quantification techniques employed. Because of the complexity of the matrices studied, it was necessary to employ matrix-matched calibration. When using HPLC-DAD recoveries of 79 to 124% were obtained, with LC-MS-MS the recoveries were 83 to 119% and when using UPLC they were 78 to 113%, with coefficients of variation below to 15% for all chromatographic techniques. These limits of quantification show that the methods developed can be used to detect these pesticides at concentrations below the MRL established by Brazilian and USA legislation. UPLC-DAD had a more rapid analysis time, 7 min, and LC-MS-MS had the best selectivity and detectivity (4 mg L). The methods were applied to samples collected in markets of Campinas city, and the pesticide most frequently found was imidacloprid, with concentrations well below the listed MRL / Doutorado / Quimica Analitica / Doutor em Ciências

Made available in DSpace on 2016-08-16T18:18:42Z (GMT). No. of bitstreams: 1 TESE SELMA DO NASCIMENTO SILVA.pdf: 3613537 bytes, checksum: e7528662a8a3d2ec2dc6bf7166cc0e52 (MD5) Previous issue date: 2012-10-02 / The hypoestrogenism in climacteric is associated with vasomotor symptoms, cardiovascular disease, osteoporosis and urogenital changes. At this stage of life of women, hormone replacement HRT can alleviate some consequences of decreased estrogen caused by ovarian failure. However, estrogen therapy may cause adverse effects such as breast tenderness, uterine bleeding and increase the relative risk for cancers of the breast and endometrium. Morus nigra L. (mulberry) is a plant species most used in Brazil for the treatment of menopausal symptoms. Thus, this study aims to assess the likely effects phytoestrogenics the hydroalcoholic extract (HE) from the leaves of M. nigra in ovariectomized female rats. Therefore, the dried leaves were pulverized and soaked in 70% ethanol in the proportion 1:3 (v/v) to obtain the HE (yield=21.90%). The HE was subjected to evaluation of the antioxidant activity by capturing free radical 2,2-diphenyl-1-picryl-hidrazil, analyzed by liquid chromatography coupled to mass spectrum (LC-MS/MS) for identification of compound and then partitioned with hexane, chloroform, ethyl acetate and methanol/water. The safety of extract was determined by the test of acute toxicity in mice at doses of 0.1 to 10.0 g/kg orally (p.o.). To evaluate the estrogenic activity of the extract from M. nigra leaves, the rats were divided into two control groups: sham-operated (SHAM) and ovariectomized (OVX), which received 0.1 mL/100 g saline, and two test groups: ovariectomized and treated with a solution estroprogestative (OVX-EP-50g/kg) and ovariectomized and treated with HE M. nigra 500mg/kg (OVX-HE500), n = 8-10, daily, p.o., for 14 weeks. Throughout the treatment period were analyzed the frequency stage of the estrous cycle, food intake and body weight. At the end of treatment were evaluated biochemical parameters and hormone, histomorphometry of the uterus, vagina and breast. Furthermore, the influence of M. nigra on the proliferation of breast tumor cell line MCF-7 was determined by MTT method. HE showed high antioxidant activity when compared to standard quercetin. The analysis by LC-MS/MS EH compared with literature data allowed the identification of flavonoids (kaempferol and quercetin) and quinic acid derivatives (caffeoylquinic acid and isomers dicaffeoylquinic acid). In the analysis of the estrous cycle, the group OVX-HE500 showed an increase in proestrous and estrous phases at 15.25% and 26.6%, respectively, when compared to OVX group. Ovariectomy caused an increase in body mass, which was prevented by treatment with HE and EP solution. The weight of abdominal adipose tissue was also significantly lower in groups OVX-HE and OVX-EP compared to the OVX group. Ovariectomy also induced atrophy of uterine tissue (OVX group) compared to SHAM group, indicating the efficiency of the surgical procedure, and the administration of EP significantly increased uterine weight compared with OVX group. Average uterine weight of the OVX-HE group was also higher than the OVX group, but smaller than the OVX-EP group. In the histological analysis, it was observed that the characteristics of the squamous epithelium of the vagina of OVX-EP group (57.79 ± 1.49m), relative to thickness, were similar to that of SHAM group (50 66 ± 1.60m). After 14 weeks of administration of HE was a partial reversal of vaginal atrophy (37.34 ± 1.77m), when compared to the OVX group (12.92 ± 0.53m), showing maturation of this tissue with the treatment, however, the HE did not alter breast tissue, unlike the stimulus EP-induced. Regarding biochemistry was observed that the treatments (HE and EP) reduced concentrations of triglycerides in 27.5% and 23.8% respectively, when compared to OVX. In in vitro tests, the data indicate that the HE M. nigra acts as a weak phytoestrogen and protects against cell proliferation of human breast carcinoma (MCF-7). In acute toxicity study, the treatment of mice with HE did not produce behavioral changes or deaths. Together, the data demonstrate that the HE M. nigra L. has beneficial effects in models of induced menopause in rats, decreased uterine and vaginal atrophy, without changing the mammary structure, improving triglyceride levels and shows up secure and potent oxidant activity. These effects may be related to their flavonoid constituents, and thus the plant species may be useful in controlling symptoms of menopause as an alternative to Hormone Replacement Therapy. / O hipoestrogenismo no climatério associa-se com sintomas vasomotores, doenças cardiovasculares, osteoporose e alterações urogenitais. Nesta fase da vida da mulher, a reposição hormonal pode amenizar algumas consequências da diminuição estrogênica ocasionada pela falência ovariana. Porém, a terapia estrogênica pode ocasionar efeitos adversos como mastalgia, sangramentos uterinos, além de aumentar o risco relativo para neoplasias de mama e endométrio. Morus nigra L. (amora) é uma das espécies vegetais mais utilizadas no Brasil para o tratamento dos sintomas do climatério. Assim, o presente estudo objetiva avaliar os prováveis efeitos fitoestrogênicos do extrato hidroalcoólico (EH) das folhas de M. nigra em ratas Wistar ovariectomizadas. Para tanto, as folhas secas foram pulverizadas e maceradas em etanol a 70% na proporção 1:3 (v/v), para obtenção do EH (rendimento=21,90%). O EH foi submetido à avaliação da atividade antioxidante pela captura do radical livre 2,2-difenil-1-picril-hidrazila, analisado por cromatografia líquida acoplada ao espectro de massa (LC-MS/MS) para identificação de composto e, em seguida, particionado com hexano, clorofórmio, acetato de etila e metanol/água. A segurança do extrato foi determinada pelo teste de toxidade aguda em camundongos, nas doses de 0,1 10,0g/kg, por via oral (v.o.). Para avaliar a atividade estrogênica do extrato das folhas de M. nigra, as ratas foram divididas em dois grupos controle: falso-operados (SHAM) e ratas ovariectomizadas (OVX), que receberam 0,1mL/100g de solução salina; e dois grupos teste: ovariectomizadas e tratadas com solução estroprogestativa (OVX-EP-50g/Kg) e ovariectomizadas e tratadas com EH de M. nigra 500mg/kg (OVX-EH500), n=8-10, diariamente, por v.o., durante 14 semanas. Durante todo o período de tratamento foram analisadas a frequência das fases do ciclo estral, a ingestão de alimentos e o peso corporal. Ao final do tratamento foram avaliados os parâmetros bioquímicos e hormonais, histomorfometria do útero, vagina e mama. Além disso, a influência de M. nigra sobre a proliferação de células tumorais de mama da linhagem MCF-7 foi determinada pelo método MTT. O EH apresentou alta atividade antioxidante quando comparada ao padrão quercetina. Na análise do EH por LC-MS/MS em comparação com dados da literatura permitiu a identificação de flavonoides (caempferol e quercetina) e derivados do ácido quínico (ácido cafeoilquínico e isômeros de ácido dicafeoilquínico). Na análise do ciclo estral, o grupo OVX-EH500 apresentou um aumento nas fases estro e proestro em 15,25% e 26,6%, respectivamente, quando comparado ao grupo OVX. A ovariectomia promoveu um aumento no peso corporal, que foi inibido pelo tratamento com o EH e solução EP. O peso do tecido adiposo abdominal também foi significativamente menor nos grupos OVX-EP e OVX-EH, quando comparados ao grupo OVX. A ovariectomia também induziu atrofia do tecido uterino (Grupo OVX) em comparação ao grupo SHAM, indicando a eficiência do procedimento cirúrgico; e a administração de EP aumentou significativamente o peso do útero em comparação com grupo OVX. A média do peso uterino do grupo OVX-EH também foi maior do que o grupo OVX, porém menor que o grupo OVX-EP. Quanto à análise histológica, observou-se que as características do epitélio escamoso da vagina do grupo OVX-EP (57,79 ± 1,49m), em relação à espessura, se assemelharam à das ratas do grupo SHAM (50,66 ± 1,60m). Após 14 semanas de administração de EH houve uma reversão parcial da atrofia vaginal (37,34 ± 1,77m), quando comparado ao grupo OVX (12,92 ± 0,53 m), mostrando maturação deste tecido com o tratamento; entretanto, o EH não alterou o tecido mamário, diferente do estímulo induzido pelo EP. Em relação à bioquímica foi observado que os tratamentos (EH e EP) reduziram as concentrações de triglicérides em 27,5% e 23,8% respectivamente, quando comparado ao grupo OVX. Nos testes in vitro, os dados indicam que o EH de M. nigra atua como um fraco fitoestrógeno e protege contra a proliferação de células de carcinoma de mama humano (MCF-7). No estudo toxicológico agudo, o tratamento de camundongos com o EH não produziu alterações comportamentais nem mortes. Em conjunto, os dados demonstram que o EH de M.nigra apresenta efeitos benéficos em modelos de hipoestrogenismo induzida em ratas, diminuindo a atrofia uterina e vaginal, sem alterar a estrutura mamária, melhorando os níveis de triglicérides, tendo potencial antioxidante, além de mostrar-se seguro. Esses efeitos podem estar relacionados com seus constituintes flavonoídicos, e dessa forma, a espécie vegetal pode ser útil no controle de sintomas da menopausa como uma alternativa para Terapia de Reposição Hormonal.

Orientador: Marcelo Alexandre Prado / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-21T09:52:53Z (GMT). No. of bitstreams: 1 MirandaeSilva_LigiaMaria_M.pdf: 148256 bytes, checksum: 789cac2002bb2e8dcb1bf70832d395b6 (MD5) Previous issue date: 2012 / Resumo: O crescente aumento populacional em escala mundial, tornou necessário um grande esforço por parte da agricultura para aumentar, a cada ano, a produção de alimentos para atender as necessidades do mercado externo e interno do Brasil. Recursos técnicos e científicos passaram então, a serem aplicados em busca da melhoria na produção dos cultivos,principalmente mediante o uso de fertilizantes e praguicidas. Com isso, a sociedade se deparou com problemas de ordem de equilíbrio ambiental e saúde pública, pois devido à contínua diversificação dos fitoparasitas, surgem, a todo momento, reduções do período de tempo entre aplicações consecutivas, e mais importante talvez, usos de doses mais altas e emprego simultâneo de diferentes pesticidas, por parte dos agricultores, objetivando complementar ações específicas ou alcançar efeitos sinérgicos para maiores rendimentos na produção. Tal situação traz como conseqüência óbvia e direta, o aumento, inaceitável, dos riscos de contaminação do meio ambiente com resíduos químicos de defensívos da área agropecuarista prejudiciais à saúde, o que leva a inúmeros problemas relativos à segurança alimentar dos produtos consumidos, e à uma preocupação de âmbito nacional evidenciada pela criação do Programa de Análise de Resíduos de Agrotóxicos em alimentos (PARA) da ANVISA. O aumento na necessidade de detecção e quantificação destes compostos, acarretou o desenvolvimento de pesquisas no setor, a fim de atingir uma melhoria na eficiência,qualidade e rapidez de resposta nas análises. A possibilidade do estudo de não apenas um de cada vez, mas de até 300 compostos sendo extraídos, detectados e quantificados simultâneamente se tornou a saída mais viável, tanto qualitativa quanto economicamente, facilitando o monitoramento contínuo do fornecimento de produtos do setor alimentício pelos chamados métodos multiresíduos. O presentre trabalho teve como princípio a validação de um método multiresíduo para análise de 14 analitos usando uma técnica de alto poder de concentração e limpeza do extrato como o GPC (Gel Permeation Chromatography) e detecção e quantificação por GC-MS/MS e LC-MS/MS. Os pesticidas investigados englobam classes como: acaricidas, inseticidas, fungicidas, nematicidas e formicidas de aplicação foliar, em sementes ou em solo, sendo que o acefato, metamidofós, acetamiprido e o thiamethoxan foram extraídos de amostras de batata e feijão e analisados por LC-MS/MS e a azoxistrobina, bifentrina, carbofuran, chlorotalonil, clorpirifós, clorfenapir, etofenprox, famoxadone,metalaxil, procimidone e o tebuconazole em amostras de batata e tomate e analisados por GCMS/MS. Os limites de detecção (LD) encontrados variaram de 0,06 a 2,89µg/L, e os coeficientes de variação (CV), de 0,036 a 2,036%. As recuperações foram determinadas em cada tipo de amostras, e os valores encontrados estavam entre 93,34% e 109,67%. Nenhuma das matrizes utilizadas apresentaram resultados insatisfatórios e o método utilizado mostrouse robusto e de fácil aplicação para todos os analitos testados / Abstract: The growing population worldwide, has required a great effort on the part of agriculture to increase each year, the production of food to meet the needs of external and internal market of Brazil. Technical and scientific resources spent then, to be applied in pursuit of improved crop production, mainly through the use of fertilizers and pesticides.With this, the company encountered problems in the balance of environmental and public health, since due to the continuous diversification of plant parasites, arise at any moment,reductions in the time period between consecutive applications, and perhaps most important,uses more doses high and simultaneous use of different pesticides by farmers, aiming to complete specific actions or to achieve synergistic effects in producing higher yields. This situation brings obvious and direct consequence, the increase unacceptable risk of environmental contamination with chemical residues from pesticides in farms are harmful to health, which leads to numerous problems relating to food safety of the products consumed, and to a concern nationwide evidenced by the creation of the Program Analysis of Pesticide Residues in Food (TO) of ANVISA. The increase in the necessity for detection and quantification of these compounds, led the development of research in the sector in order to achieve an improvement in efficiency, quality and responsiveness in the analyzes. The possibility of studying not just one at a time, but up to 300 compounds being extracted,detected and quantified simultaneously output became more viable, both qualitatively and economically, facilitating continuous monitoring of the supply of products by the food industry called methods multiresidue. The principle presentre work was the validation of a multiresidue method for analysis of 14 analytes using a technique of high power concentration and cleanup of the extract as GPC (Gel Permeation Chromatography) and detection and quantification by GC-MS/MS and LC- MS / MS. The pesticides investigated include classes such as acaricides, insecticides, fungicides, insecticides and nematicides foliar, seed or soil,and acephate, methamidophos, and Acetamiprid thiamethoxan were extracted from samples of potatoes and beans and analyzed by LC-MS / MS and azoxystrobin, bifenthrin, carbofuran,chlorothalonil, chlorpyrifos, chlorfenapyr, etofenprox, famoxadone, metalaxyl, procymidone and tebuconazole in samples of potato and tomato and analyzed by GC-MS/MS. The limits of detection (LOD) ranged from 0.06 to 2.89 mg / L, and the coefficients of variation (CV), 0.036 to 2.036%. The recoveries were determined for each type of samples, and the values were between 93.34% and 109.67%. None of the arrays used had unsatisfactory results and method proved to be robust and easy to apply for all analytes tested / Mestrado / Ciência de Alimentos / Mestra em Ciência de Alimentos

Ce projet de recherche comporte deux parties principales qui possèdent comme lien unificateur l’amélioration des méthodes et techniques utilisées actuellement pour évaluer aussi bien l’activité que l’expression des cytochromes P450 (CYP450s) et menant par la suite à leur application en clinique. Le premier volet de ce projet de recherche porte sur le développement de méthodes LC-MS/MS pour un cocktail de 7 substrats marqueurs des CYP450s. Notre objectif est de développer et valider une méthode LC-MS/MS spécifique et sensible permettant l’évaluation des activités des CYP1A2, 2B6, 2C9, 2C19, 2D6, 3A4/5 et 2E1 suivant l’administration orale et à faible dose d’un cocktail de substrats marqueurs chez des patients et sujets sains. Les méthodes développées peuvent être utilisées pour évaluer les mécanismes de variabilité interindividuelle comme l’impact de polymorphismes génétiques, de facteurs environnementaux et de maladies dans le processus de métabolisme et d’élimination des médicaments, mais également pour investiguer les interactions médicamenteuses. Ce cocktail a été appliqué avec succès, dans un projet clinique portant sur l’évaluation des effets du diabète sur la capacité métabolique par les CYP450s. Le deuxième volet de ce projet de recherche vise à développer des méthodes analytiques par LC-HRMS afin de caractériser et quantifier les CYP1A1, 1A2, 1B1, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, 2J2, 3A4, 3A5, 3A7 et 4F2 dans l’intestin grêle humain. Notre hypothèse suggère que les CYP450s retrouvés le long de l’intestin grêle peuvent affecter significativement l’effet de premier passage de certains médicaments administrés par voie orale et influencer leurs concentrations plasmatiques et conséquemment, leurs effets pharmacologiques et/ou toxiques. Ma participation à ce projet a permis d’identifier des peptides protéotypiques par digestion in silico et in vitro et de développer des méthodes de quantification absolue par LC-HRMS. Ce projet est une première étape dans la caractérisation des CYP450s majeurs le long de l'intestin grêle. Il permettra de mieux comprendre les mécanismes de variabilité interindividuelle dans la réponse aux médicaments associés au processus d'absorption intestinal et de mieux prédire la variabilité dans la biodisponibilité des médicaments et de développer des modèles pharmacocinétiques plus complexes. / This research project is divided into two sections, both aiming at the development of sensitive and specific LC-MS methods to evaluate activity and expression of CYP450 and finally, looking at their clinical application. The first section of this research project focuses on the development of analytical methods by LC-MS/MS for a seven CYP450 probe-drug cocktail. Although these cocktails have shown value they also suffer from many limitations. Our objective was to develop and validate highly sensitive and selective LC-MS/MS assays allowing the determination of CYP1A2, 2B6, 2C9, 2C19, 2D6, 3A4/5 and 2E1 activities following administration of low oral doses of a modified CYP450 probe-drug cocktail in patients. These methods can be used to phenotype CYP450 activities, evaluate inter-individual variabilities, study the impact of pathological conditions on drug metabolism and elimination, and evaluate drug-drug interactions. Our CYP450 cocktail assays have been successfully applied to phenotype CYP450 activities in type 2 diabetic patients. The second section of this project aims at the development of a LC-HRMS method for the characterization and absolute quantification of CYP1A1, 1A2, 1B1, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, 2J2, 3A4, 3A5, 3A7 and 4F2 in the human small intestine. Our hypothesis suggests that CYP450 isoenzymes found along the small intestine can significantly affect the first-pass effect of certain drugs administered orally and thus influence their pharmacological and/or toxic effects. My participation in this project allowed to identify proteotypic peptides by in silico and in vitro digestion and to develop LC-HRMS methods allowing the absolute quantification of CYP450. This project is a first step in the characterization of the main CYP450 along the small intestine. This project will allow a better understanding of inter-individual variability in drug response associated with intestinal absorption of drugs, a better prediction of variability in drug bioavailability and to develop more complex pharmacokinetic models.

The stem bark of the protected tree species, Curtisia dentata (Burm. f.)C.A.Sm., is one of the most popular plant species harvested and traded at traditional medicine markets in South Africa. The overexploitation of C. dentata trees lead to a “Near Threatened” conservation status and the population trend is portrayed as “declining”. In the KwaZulu-Natal Province of South Africa, C. dentata is completely conservation dependent. This study is not based on drug discovery or toxicological studies, but on the concern that the stem bark of C. dentata trees are harvested, prepared into remedies and consumed as traditional medicine without knowledge regarding the chemical compounds in the stem bark, particularly since the chemical composition of C. dentata stem bark was unknown to date. Phytochemical analyses were firstly conducted to determine the chemical composition of C. dentata stem bark using various solvents and various analytical methods, and secondly, to determine how seasons and regional separation of C. dentata trees affect the chemical profiles of C. dentata stem bark from an environmental and nature conservation perspective. Plants are known to contain numerous chemical compounds. Compounds isolated from a particular plant species are therefore not the only compounds present in that species, and although a plant has proven pharmacological properties, they can still cause harm. Previous studies on C. dentata aimed at validating the plant species as a medicinal plant by examining extracts of the leaves, twigs and stem bark’s potentials against known pathogens and selected cancer cells in vitro and in vivo, and its anti-inflammatory, antioxidant and antiverotoxic properties. Four pentacyclic triterpenoids and one steroidal compound were also previously isolated from C. dentata leaves, however, the leaves are not used in traditional medicines, but were suggested as alternative for stem bark as the harvesting of leaves is less destructive. The efficacy of these compounds as therapeutic agents is, however, compromised by their low solubility in water and thus their potential to penetrate permeating biological membranes. Moreover, in vitro toxicity studies distort the picture of its actual potentials on human health as the whole human metabolome and all its processes, including uptake and phase I and phase II biotransformation are not included. In vivo toxicity studies on mammalian animal species may also not present a true picture of a chemical or extract’s toxic effects on humans as animal metabolisms differ from those of humans. The chemical composition of leaves and stem bark may furthermore also be in contrast to some extent, and therefore chemical compounds were also isolated from C. dentata stem bark in this study. Scientific studies on plant-based medicines generally involve the discovery or identification of compounds that may be beneficial, and which can be exploited in future. Chemical compounds in traditional medicines or other plant-based health products which may cause adverse effects are generally ignored. Moreover, scientific studies that consider that some compounds present in plant extracts may derive from contaminants are equally limited. Traditional plant-based medicines are neither standardized nor regulated in South Africa. Users of traditional plant-based traditional medicines therefore consume uncertain dosages of both beneficial and hazardous substances, as well as contaminants simultaneously. Certain chemical compounds are carcinogens or mutagens or have the ability to accumulate in human tissues. Adverse effects may therefore only manifest after several years of use and will subsequently not be connected to the use of a particular traditional plant-based medicine. The goal of the thesis is therefore to provide a holistic portrayal of the full spectrum of chemical compounds in extracts of C. dentata stem bark and to discuss, where literature is available, the effect(s) each chemical compound may have on human health. Moreover, this thesis investigates variations in chemical composition and concentration in individual trees, seasonal variations and variations in composition and concentrations in the stem bark of C. dentata trees from geographically distinct regions. Most unexpected was that not all C. dentata stem bark samples contained chemical compounds with known beneficial potentials at each sampling date, and that chemical compounds may be region-specific and also tree-specific, which confirms that plants produce secondary metabolites according to the needs of each individual plant. Additional insight into the chemical composition and concentration of C. dentata trees is provided by the distribution profiles of amino acids in C. dentata stem bark. Extreme variations within populations and between geographical areas support the need for the cultivation of C. dentata trees to ensure sustainable production of homogenous material for chemical homogeneity. / Environment Science / PhD. (Environment Science)

Plasmodium falciparum is a protozoan parasite responsible for causing the most severe form of malaria in humans. This species is responsible for over 90% of malaria mortalities which occur predominantly in Africa. An increase in drug resistant parasites in recent years is threatening the progress made against malaria and thus new antimalarial drugs and vaccines are needed to combat this disease. During the intraerythrocytic phase, merozoites egress from mature schizonts to invade new uninfected erythrocytes. Glycophosphatidylinositol (GPI) -anchored proteins cover most of the exterior surface of the merozoite prior to invasion, while other GPI-anchored proteins are released onto the merozoite surface through apical organelle secretions. These proteins are involved in interactions with erythrocytes and are thought to be vital to erythrocyte invasion. GPI-anchored proteins have also been implicated as a cause of pathogenic symptoms and activation of immune components. These proteins are then released or cleaved to enable merozoite entry into the erythrocyte. Several enzymes are thought to be involved in their cleavage including the serine proteases subtilisin-like proteases (SUB) 1 and 2, and phosphatidylinositol-phospholipase C (PIPLC); GPI-anchored proteins are also generally sensitive to phospholipase A2 (PLA2). Cleaved proteins are released into the host blood system, while uncleaved proteins are carried into the erythrocyte during invasion. Merozoites have a limited period in which they retain invasive capacity. A previous lack of available techniques that are specifically adapted to merozoite analysis has resulted in an incomplete understanding of invasion and GPI-anchored protein involvement in invasion. This study aimed to determine how GPI-anchored proteins on the merozoite surface are altered in the invasive phase, and explore the possibility of using merozoite GPI-anchored proteins as potential drug targets to block erythrocyte invasion. Optimised methods of in vitro parasite culturing which produce highly synchronised merozoites was essential to this study. Parasite culturing techniques were optimised by utilising low haematocrit cultures with frequent culture splitting and optimised synchronisation. The “Malarwheel” is a tool that was developed for this research to provide a means for scheduling sorbitol treatments and MACs isolations. This tool and optimised culturing methods enabled large volumes of highly synchronised invasive merozoites to be harvested. Four compounds (vanadate, edelfosine, dioctyl sodium sulfosuccinate (DSS), and gentamicin) suspected to interfere with GPIanchored cleavage or processes were screened on intraerythrocytic stages and merozoites. Antimalarial and anti-invasive properties of these compounds were screened by modified malaria SYBR Green I-based fluorescence (MSF) assay and merozoite invasion assays (MIA) respectively. DSS and gentamicin showed limited potential as antimalarials or as anti-invasive agents. Vanadate and edelfosine both showed antimalarial and anti-invasive activity, while edelfosine was the most potent anti-invasive agent at physiological concentrations. The merozoite GPI-anchored proteome was analysed by sodium dodecyl sulphatepolyacrylamide gel electrophoresis (SDS-PAGE) followed by complete gel lane analyses conducted by liquid chromatography-tandem mass spectrometry (LC-MS/MS) on soluble and pelleted merozoite proteins in samples from either invasive or non-invasive merozoites. Thirteen known or predicted GPI-anchored proteins were identified in samples. Several changes were identified in merozoite GPI-anchored proteins between the invasive phase and after its completion, and minor differences were observed following treatment with edelfosine. Edelfosine showed partial inhibition of erythrocyte invasion, however, the primary cause of inhibition cannot be directly related to interferences with GPI-anchored proteins. These results suggest that GPIanchored proteins are controlled by various complex processes, and are cleaved or processed by diverse mechanisms during the invasive phase. These mechanisms may be controlled by multiple signals which effect proteins or groups of proteins in specific ways. These signals may be influenced by “checkpoints” during invasion processes including the time period after egress from schizonts, and possibly the recognition of erythrocyte targets. These methods and results provide a foundation for future research to enable culturing of P. falciparum parasites specifically for merozoite research, and to identify merozoite proteins active during the invasive phase. These results confirm and challenge previous ideas reported in literature on the GPI-anchored processes of merozoites and further characterise less studied GPIanchored proteins. The results suggest that the processes controlling GPI-anchored proteins may be more complex than previously thought. These results form a basis to further identify and characterise GPI-anchored proteins in the aim to develop antimalarial medications and vaccines that target merozoites and their GPI-anchored processes. / Dissertation (MSc)--University of Pretoria, 2017. / Pharmacology / MSc / Unrestricted

No description available.

La cholestase intrahépatique de la grossesse (CIG) est la maladie du foie la plus répandue au cours de la grossesse. Elle est caractérisée par un prurit et est associée à une augmentation de la concentration des acides biliaires dans le sang, ce qui peut mener à un risque accru de conséquences périnatales indésirables, y compris un accouchement prématuré spontané et une augmentation des risques de mort de l’enfant à l’accouchement, entre autres. Le traitement médical de cette maladie repose actuellement sur l’acide ursodésoxycholique (UDCA) qui diminue le prurit et les anomalies biochimiques maternelles dans certains cas. Actuellement, le diagnostic de la CIG est posé suite à un test de quantification des acides biliaires sériques totaux par une méthode enzymatique. Nous émettons l'hypothèse que certains profils d’acides biliaires permettraient d’évaluer le risque de complications chez les femmes atteintes de CIG. En analysant les profilages, il pourrait être possible de déterminer la ou les espèces responsables de ces complications et ainsi déterminer des sous-groupes de patientes plus à risque de complications ou qui répondraient mieux au traitement. De plus, nous pensons que le traitement à l’UDCA, étant lui-même un acide biliaire, pourrait interférer lors de la quantification des acides biliaires totaux sériques, particulièrement dans les cas les plus problématiques de CIG où de fortes doses de ce composé sont administrées. Si c’était le cas, cela ferait en sorte que les valeurs de référence pourraient être modifiées en fonction du traitement administré. Le projet de recherche présenté vise au développement d’une méthode de quantification des acides biliaires sériques par la chromatographie liquide couplée à un spectromètre de masse en tandem (LC-MS/MS), qui permettrait un profilage des acides biliaires sériques chez les femmes enceintes atteintes de la CIG et qui permettrait également d’évaluer l’effet du traitement à l’UDCA sur ce profilage. Une méthode de quantification des acides biliaires par chromatographie liquide couplée à un spectromètre de masse en tandem a été développée et validée. Les surnageants obtenus par précipitation de protéines avec le méthanol ont été injectés sur le LC-MS/MS. La séparation est réalisée par chromatographie en phase inverse sur une colonne C18 de type interactions hydrophobes. Les transitions ioniques sur le spectromètre de masse ont été déterminées pour toutes les espèces d’acides biliaires au préalable et l’acide cholique deutéré, l’acide chénodésoxycholique deutéré ainsi que l’acide désoxycholique deutéré ont été utilisés comme standards internes. Quinze acides biliaires, y compris les acides biliaires conjugués et libres, ont été séparés et quantifiés par LC–MS/MS en utilisant l’ionisation par électro nébulisation (ESI) en mode ion négatif. La quantification a été réalisée en mode de surveillance de réactions multiples (MRM) avec des méthodes de courbes d'étalonnage externes. Les coefficients de corrélation des courbes standards pour tous les acides biliaires étaient supérieurs à 0,9966. La méthode développée a démontré une précision acceptable, avec une imprécision intra analyse inférieure à 3,2% pour toutes les espèces d’acide biliaire étudiées (pour des échantillons à 0,8 et 5 μg/mL) et une imprécision inter analyse inférieure à 15%. Une suppression d’ion moyenne de 8,2% a été observée, qui a été jugée acceptable. Une bonne corrélation a été obtenue entre la méthode LC-MS/MS et une méthode enzymatique (r=0,964). En conclusion, une méthode fonctionnelle, efficace et rapide a été développée pour quantifier les acides biliaires sériques individuels et différents profils d’acides biliaires représentant une large gamme de concentrations ont été comparés. La comparaison des profilages d’acides biliaires suggère que les acides biliaires principaux responsables de l’augmentation de la concentration des acides biliaires totaux dans le sang pour des échantillons à une concentration de plus de 10 μmol/L sont l’acide cholique glyco-conjugué (GCA), l’acide cholique tauro-conjugué (TCA) ainsi que l’acide ursodésoxycholique glyco- conjugué (GUDCA). Cette nouvelle méthode validée, et les données préliminaires sur les profils d’acides biliaires dans les échantillons cliniques, permettront de lancer des analyses cliniques prospectives pour évaluer l’effet du traitement par l’UDCA sur les concentrations totales d’acides biliaires sériques et sur les profils d’acides biliaires individuels chez les patientes atteintes de la CIG. / Intrahepatic cholestasis of pregnancy (ICP) is the most common liver disease during pregnancy. It is characterized by pruritus and is associated with an increased concentration of bile acids in blood, which may lead to an increased risk of perinatal consequences, including spontaneous preterm delivery and an increased risk of death at birth, among others. The medical treatment of this disease currently relies on ursodeoxycholic acid (UDCA) which reduces pruritus and maternal biochemical abnormalities in some cases. Currently, the diagnosis of ICP is made using an enzymatic assay to measure total serum bile acids. We hypothesize that profiling of the individual bile acids would make it possible to assess the risk of complications in women with ICP. By analyzing the bile acid profiles, it could be possible to determine which specie(s) is responsible for these complications and thus to distinguish subgroups of patients at higher risk of complications or who would respond better to treatment. In addition, we believe that UDCA treatment, being a bile acid itself, could interfere with the quantification of total serum bile acids, particularly in the most problematic cases of CIG where high doses of this compound are administered. If this was the case, it would mean that the reference values would need to be changed depending on the administered treatment. The research project aims to develop and validate a method for quantifying bile acids in serum by liquid chromatography coupled to a tandem mass spectrometer (LC-MS/MS), which would allow profiling of serum bile acids in affected women and which would also make it possible later to evaluate the effects of UDCA treatment on this profiling. A method for the quantification of bile acids by liquid chromatography coupled to tandem mass spectrometry has been developed and validated. The supernatants obtained by precipitation of proteins with methanol were injected onto the LC-MS/MS. The separation was carried out using reversed-phase chromatography on a C18 hydrophobic interactions type column. Ionic transitions on the mass spectrometer were determined for all bile acids species beforehand and deuterated cholic acid, deuterated chenodeoxycholic acid and deuterated deoxycholic acid were used as internal standards. Fifteen bile acids, including conjugated and free bile acids, were separated and quantified by LC–MS/MS using electrospray ionization (ESI) in negative ion mode. Quantification was performed in multiple reaction monitoring (MRM) mode with external calibration curve methods. Correlation coefficients for standard curves for all bile acids were greater than 0.9966. The method developed showed acceptable precision, with intra-assay imprecision of less than 3.2% for all the bile acid species studied (for samples at 0.8 and 5 μg/mL) and inter-assay imprecision under 15%. An average ion suppression of 8.2% was observed, which was judged acceptable. Finally, a good correlation was obtained between the LC-MS/MS method and an enzymatic method (r = 0.964). In conclusion, a functional, efficient and rapid method was developed to quantify the individual serum bile acids and different bile acids profiles representing a wide range of concentrations were compared. The comparison of the bile acid profiles suggests that the main bile acids responsible for the increase in total bile acids concentration in blood for samples at a concentration of more than 10 μmol/L are glycocholic acid (GCA), taurocholic acid (TCA), glycoursodeoxycholic acid (GUDCA). This new validated method, and the preliminary data on bile acid profiles in clinical samples, will allow us to initiate prospective clinical analyses to assess the effect of UDCA treatment on total bile acid concentrations and profiles in patients with intrahepatic cholestasis of pregnancy.