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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.
31

Estudos farmacocineticos do sup131I-steviosideo e seus metabolitos

CARDOSO, VALBERT N. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:37:34Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:32Z (GMT). No. of bitstreams: 1 05177.pdf: 1071515 bytes, checksum: 549d323670762fe6597fcda6cf7ea4fc (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
32

Determinacao de impurezas metalicas em oxidos de terras raras de alta pureza pela espectrometria de massa (setor magnetico) com fonte de plasma induzida por argonio (HR ICP-MS) e cromatografia liquida de alto desempenho (HPLC)

PEDREIRA FILHO, WALTER dos R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:21Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:26Z (GMT). No. of bitstreams: 1 07290.pdf: 4641586 bytes, checksum: f9e82ba22fb397706f6ac72a5f266c6c (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
33

Desenvolvimento e validação da metodologia SPE-LC-MS/MS para a determinação de fármacos e droga de abuso nas águas da represa Guarapiranga - São Paulo/SP, Brasil / Development and validation of methodology SPE-LC-MS/MS for pharmaceuticals and illicit drug determination in the waters of Guarapiranga dam - Sao Paulo/SP, Brazil

SHIHOMATSU, HELENA M. 20 May 2015 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-05-20T18:11:19Z No. of bitstreams: 0 / Made available in DSpace on 2015-05-20T18:11:19Z (GMT). No. of bitstreams: 0 / Este estudo apresenta o desenvolvimento da metodologia de extração em fase sólida e separação em cromatográfica líquida acoplada a espectrometria de massas em sequencia, SPE-LC-MS/MS, para a determinação de 21 (vinte e um) fármacos pertencentes a diferentes classes terapeuticas, 1 (uma) droga de abuso e seu principal metabólito, em amostras de água superficial. A separação cromatográfica foi otimizada estudando o desempenho de fases estacionárias e fases móvies. A quantificação dos compostos selecionados foi realizada com a ionização por eletronebulização (electrospray ionization- ESI) e o espectrômetro de massas operando no modo de Monitoramento de Múltiplas Reações (Multiplas Reaction Monitoring- MRM). A validação da metodologia proposta foi realizada utilizando os parâmetros de seletividade, efeito de matriz, faixa de trabalho, linearidade, limites de detecção (LD) e quantificação (LQ), precisão, exatidão, recuperação e robustez. A validação da metodologia permitiu a sua aplicação na avaliação da distribuição dos 23 compostos selecionados, nas águas da represa Guarapiranga, um dos principais sistemas produtor de água potável da Região Metropolitana de São Paulo (RMSP). A presença desses poluentes nos ambientes aquáticos é proveniente da liberação direta do esgoto urbano das habitações do seu entorno, como consequência do precário sistema de saneamento básico. As águas da represa Guarapiranga foram avaliadas em 14 (quatorze) locais estrategicamente escolhidos e amostradas durante 3 (três) campanhas de coleta de amostra (agosto de 2011, setembro de 2012 e abril de 2013). Nessas amostras foram quantificados acetaminofeno (9,6 - 254 ng L-1), atenolol (8,5 177 ng L-1), benzoilegonina (7,9 139 ng L-1), cafeína (27 27386 ng L-1), carbamazepina (12 358 ng L-1), clortalidona (9,4 35 ng L-1), cocaína (12,8 2650 ng L-1), diclofenaco (8 35 ng L-1), enalapril (20 ng L-1), losartana (6,7 114 ng L-1) e valsartana (9,7 - 47 ng L-1). O ponto de coleta denominado de GU103-12 (23°4188.5S 46°4467.3W) foi a região que apresentou os valores mais elevados quanto ao nível de concentração dos compostos avaliados e ao índice de risco integrado de poluição química aquática (Integrated Risk Index of Chemical Aquatic Pollution IRICAP). O estudo também foi realizado em amostras de água de reservatórios das Unidades de Gerenciamento de Recursos Hídricos (UGRHI) 5 e 6 do Estado de São Paulo. Os resultados demonstraram que o uso e a ocupação do solo influenciam diretamente na qualidade da água dos reservatórios, evidenciando a necessidade de implementar melhorias no sistema de coleta de esgoto e de ocupação irregular para evitar a contaminação e o descarte inadequado em ambientes aquáticos. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
34

Carotenóides e composição centesimal de ervilhas (Pisum sativum L.) cruas e processadas / Carotenoids and centesimal composition of raw and cooked peas (Pisum sativum L.)

Otilia Teixeira de Carvalho 10 September 2007 (has links)
A ervilha é um dos alimentos mais produzidos no mundo e, conseqüentemente, tem uma grande importância para a nutrição humana, sendo comercializada sob várias formas: fresca, seca, congelada e enlatada, necessitando de cozimento antes de ser consumida. Sendo assim, podem ocorrer alterações em sua composição durante esses processamentos. O presente trabalho teve como objetivos avaliar as mudanças ocorridas devido ao processamento na composição centesimal e no perfil de carotenóides em ervilhas frescas (tortas - com vagem comestível - e em grão), secas e enlatadas e relacionar esses dados com sua origem e safra. Foram analisados seis lotes de ervilhas tortas provenientes de duas regiões produtoras (cruas e cozidas por 5 minutos), três lotes de ervilhas frescas (cruas e cozidas por 7 minutos), dois lotes de ervilhas enlatadas (processadas e sua matéria-prima) e três lotes de ervilhas secas (cruas e cozidas por 35 minutos). A umidade em ervilhas tortas diferiu entre safras e regiões produtoras e em ervilhas em grão, aumentou após o cozimento em duas amostras e variou entre safras. O cozimento ocasionou perdas nos teores de Resíduo Mineral Fixo (RMF) em ervilhas em grão e secas. Em ervilhas enlatadas, o processamento causou aumento da umidade e RMF, devido à incorporação de água e sais. Os carotenóides encontrados foram a luteína, o β-caroteno e traços de violaxantina. O perfil de carotenóides em ervilhas tortas, em grão e secas não se alterou após o cozimento, já o enlatamento revelou um aumento aparente no teor de luteína em apenas um dos lotes estudados. Os teores de luteína e β-caroteno variaram entre as diferentes épocas de coleta de ervilhas tortas, em grão e secas, porém não foi observada variação entre as duas regiões produtoras de ervilhas tortas. Os teores de luteína variaram entre as matérias-primas dos diferentes fornecedores de ervilhas enlatadas. Apenas o β-caroteno possui atividade pró-vitamínica A, porém está presente em quantidade insuficiente para fazer das ervilhas fontes desse nutriente. / Pea is one of the world\'s most produced foods and therefore has great importance for human nutrition, being commercialized under different conditions: fresh, dried, frozen and canned, and further cooking is needed before being consumed. As a result, processing can cause some changes in its composition. The aim of the present work was to evaluate the changes in the centesimal composition and carotenoids profile of garden peas, snow peas, dry peas and canned peas due to processing and to compare these data according to geographic origin and crop. Six batches of snow peas from two different regions (raw and cooked for 5 min), three batches of garden peas (raw and cooked for 7 min), two batches of canned peas (processed and raw material) and three batches of dry peas (raw and cooked for 35 min) were analyzed. Water content in snow peas differed between crops and region and, in garden peas, it increased after cooking and varied between crops. Cooking caused losses in the ash content of garden and dry peas. In canned peas, processing increased water and ash contents due to absorption of water and salt. Lutein, β-carotene and traces of violaxanthin were identified in all samples. Carotenoids profile of snow, garden and dry peas did not change after cooking while canning caused an apparent increase in lutein contents only in one batch. Snow, garden and dry peas showed differences in lutein and β-carotene amount due to crops, though different regions revealed not to influence snow peas carotenoids content. The raw material from two suppliers of canned peas differed in their content of lutein. Only β-carotene is a pro-vitamin A carotenoid, however it was found in such small quantities that peas can not be considered source of this nutrient.
35

Stanovení těžkých polycyklických aromatických uhlovodíků v půdách a sedimentech / Determination of heavy polycyclic aromatic hydrocarbons in soils and sediments

Cáhová, Miroslava January 2008 (has links)
This diploma thesis will be focused on the identification and quantification of PAHs with molecular mass exceeding 278 Da by separation and spectrometric methods available at the laboratories of ICTEP.
36

Anticancer activity of ceratotheca triloba

Naicker, Leeann January 2016 (has links)
Submitted in complete fulfillment for the Degree of Doctorate of Philosophy in Biotechnology, Durban University of Technology, Durban, South Africa, 2016. / Plants have provided a source of medicine from the beginning of human history and are the core of modern medicine. Moreover, plant based drug discovery has led to the development of various anticancer drugs (such as vincristine, vinblastine, etoposide, paclitaxel, camptothecin, topotecan and irinotecan). The use of botanical, phytochemical, biological and molecular techniques have facilitated the discovery of anthraquinones from Ceratotheca triloba that can inhibit the human topoisomerase II enzyme (target for anticancer drugs) and kill cancer cells. However, the C. triloba plant has not been extensively studied for its anticancer activity. Therefore, the aim of this study was to further investigate the anticancer activity of C. triloba and determine the classes of compounds that contributed towards its activity. In this study the leaf and root extracts were prepared by using hexane, DCM, hexane: DCM (1:1), methanol and/or water. These extracts were examined for their growth inhibitory potential on three cancer cell lines (A375 [melanoma], MDA-MB-231[breast] and WHCO1 [esophageal]) by using the MTT assay. Then, different mobile phases were prepared for optimizing the separation of the compounds of the active extract by TLC. Column chromatography was performed with the active extract by using five mobile phases (hexane : DCM [60 : 40, 40 : 60], DCM, DCM : ethyl acetate [90 : 10, 70 : 30, 60 : 40, 50 : 50, 50 : 60, 30: 60, 20 : 80], ethyl acetate and ethyl acetate: methanol [80 : 20, 70 : 30, 50 : 50]). The fractions collected from the column were examined for their growth inhibitory potential on two melanoma cell lines (A375 and UACC-62). The IC50 and TGI (total growth inhibition) values of the active fractions were determined. Also, the apoptosis inducing effects of the active fractions and standards (camptothecin and doxorubicin) were determined by using flow cytometer based assays (FITC annexin assay, PE active caspase 3 assay and BD MitoScreen assay). Subsequently, the chemical structures of the compounds that contributed towards the activity of these fractions were obtained by EI-LC-MS analysis. The results demonstrated that the hexane root extract exhibited the best percentage of growth inhibition (%GI) on all three cancer cell lines. The separation of the compounds of the hexane root extract was optimized on TLC plates by using different ratios of hexane and DCM. Column chromatography allowed for fractionation of this extract. Purified compounds were not obtained due to co-elution. Further research would have to be conducted to obtain purified compounds. This may involve the use of mini-column chromatography and PTLC. Overall a total of ten combined fractions were collected from the column. Four of these fractions (F2, F4, F5 and F8) displayed a high %GI on the A375 and UACC-62 cell lines. Moreover, fraction F4 was the most active fraction as it had the lowest IC50 (0.70 µg.ml-1 [A375] and 0.39 µg.ml-1 [UACC-62]) and TGI (12.50 µg.ml-1[A375] and 25 µg.ml-1 [UACC-62]) values in comparison to the other fractions. All four fractions induced depolarization of the mitochondria membrane potential (ΔΨ), caspase 3 activation, early apoptosis (phospholipid phosphatidylserine exposure) and/or late apoptosis in the melanoma cells. The results also revealed that fraction F4 (25 µg.ml-1) induced depolarization of the ΔΨ in a higher percentage of A375 (78.11%) and UACC-62 (87.4%) cells than the other fractions and standards. This fraction also induced caspase 3 activation in a high percentage of A375 (90.56%) and UACC-62 (96.78%) cells. Therefore fraction F4 was also the most active fraction in terms of apoptosis activity. Based on our results and literature findings we can deduce that the active fractions induced the intrinsic or extrinsic (type II) apoptosis pathway in the melanoma cells. Six classes of compounds were identified from the four active fractions. These were: benzothiophenones, benzopyranones, naphthoquinones, anthraquinones, androstanes and quinazolines. In conclusion, this is the first study that evaluated the growth inhibition potential of the leaf and root extracts of C. triloba on a panel of cancer cells. This research indicated that the hexane root extract displayed the best levels of cell growth inhibition. The active constituents of this extract were isolated into four fractions which elicited apoptosis inducing effects that promoted the extrinsic (type II) or intrinsic apoptosis pathway in the melanoma cells. Furthermore, fraction F4 contained the most active compounds from C. triloba as it had the lowest IC50 and TGI values (in comparison to the other fractions) and induced depolarization of the ΔΨ in the highest percentage of melanoma cells. It was confirmed that six classes of compounds were accountable for the anticancer activity of these fractions. Thus, the C. triloba plant is a rich source of anticancer compounds. / D
37

Caracterização físico-química da foliculotrofina humana (hFSH) recombinante e de suas subunidades, por cromatografia líquida de alta eficiência (HPLC) em fase reversa: comparação com a preparação de referência de hFSH de origem hipofisária do \"National Hormone and Pituitary Program\" dos EUA / Physico-chemical characterization of human recombinant follicle-stimulating hormone (hFSH) and its subunits by reversed-phase high-performance liquid chromatography (RP-HPLC): comparison with pituitary hFSH reference preparation from National Hormone and Pituitary Program from USA

Renan Fernandes Loureiro 06 November 2006 (has links)
Um método de cromatografia líquida de alta eficiência por fase reversa (RP-HPLC) para análise qualitativa e quantitativa do hormônio folículo estimulante humano íntegro (hFSH), foi estabelecido e validado quanto à exatidão, precisão e sensibilidade. O FSH humano é um hormônio glicoprotéico dimérico largamente utilizado em medicina reprodutiva tanto para diagnóstico quanto para terapia. A metodologia desenvolvida preserva a integridade da proteína, permitindo a análise da forma heterodimérica intacta, e não somente de suas subunidades, como é normalmente obtida na maioria das condições geralmente empregadas. Esta técnica foi também utilizada para a comparação da hidrofobicidade relativa de preparações de hFSH hipofisária, urinária e derivadas de células de ovário de hamster chinês (CHO) bem como de outros dois hormônios glicoprotéicos, sintetizados na hipófise anterior: hormônio humano estimulante da tireóide (hTSH) e hormônio luteinizante humano (hLH). O menos hidrofóbico dos três hormônios analisados foi o hFSH, seguido do hTSH e do hLH. Uma diferença significativa (p<0,005) foi observada entre o tempo de retenção (tR) das preparações hipofisária e recombinante de hFSH, refletindo diferenças estruturais nas suas cadeias de carboidratos. Duas isoformas principais foram detectadas no hFSH urinário, incluindo uma forma que foi significativamente diferente (p<0,005) das preparações hipofisária e recombinante. Foram demonstradas linearidade da curva dose-resposta (r=0,9965, n=15) para esta metodologia de RP-HPLC, bem como uma precisão inter-ensaio, cujo coeficiente de variação é menor que 4%, para a quantificação de diferentes preparações de hFSH e uma sensibilidade da ordem de 40 ng. Foram também analisados o comportamento cromatográfico e a hidrofobicidade relativa das subunidades individuais das preparações recombinantes e hipofisária de hFSH. Além disso, a exata massa molecular das subunidades individuais de hFSH e do heterodímero foram simultaneamente determinadas por espectrometria de massa MALDI-TOF. A presente metodologia representa, em nossa opinião, uma ferramenta essencial para a caracterização e controle de qualidade deste hormônio, que ainda não consta das principais farmacopéias. / A reversed-phase high-performance liquid chromatography (RP-HPLC) method for the qualitative and quantitative analysis of intact human follicle-stimulating hormone (hFSH) was established and validated for accuracy, precision and sensitivity. Human FSH is a dimeric glycoprotein hormone widely used as a diagnostic analyte and as therapeutic product in reproductive medicine. The technique developed preserves the protein integrity, allowing the analysis of the intact heterodimeric form rather than just of its subunits, as it is the case for the majority of the conditions currently employed. This methodology has also been employed for comparing the relative hydrophobicity of pituitary, urinary and two Chinese hamster ovary (CHO)-derived hFSH preparations, as well as of two other related glycoprotein hormones of the anterior pituitary: human thyroid-stimulating hormone (hTSH) and human luteinizing hormone (hLH). The least hydrophobic of the three glycohormones analyzed was hFSH, followed by hTSH and hLH. A significant difference (p<0.005) was observed in tR between the pituitary and recombinant hFSH preparations, reflecting structural differences in their carbohydrate moieties. Two main isoforms were detected in urinary hFSH, including a form which was significantly different (p<0.005) for the pituitary and recombinant preparations. The linearity of the dose-response curve (r = 0.9965, n = 15) for this RP-HPLC methodology, as well as an inter-assay precision with relative standard deviation less than 4% for the quantification of different hFSH preparations and a sensitivity of the order of 40 ng, were demonstrated. The chromatographic behavior and relative hydrophobicity of the individual subunits of the pituitary and recombinant preparations were also analyzed. Furthermore, the accurate molecular mass of the individual hFSH subunits and of the heterodimer were simultaneously determined by matrix-assisted laser desorption ionization time-of-flight mass spectral analysis (MALDI-TOF-MS). The present methodology represents, in our opinion, an essential tool for characterization and quality control of this hormone that is not yet described in the main pharmacopoeias.
38

Caracterização físico-química da foliculotrofina humana (hFSH) recombinante e de suas subunidades, por cromatografia líquida de alta eficiência (HPLC) em fase reversa: comparação com a preparação de referência de hFSH de origem hipofisária do \"National Hormone and Pituitary Program\" dos EUA / Physico-chemical characterization of human recombinant follicle-stimulating hormone (hFSH) and its subunits by reversed-phase high-performance liquid chromatography (RP-HPLC): comparison with pituitary hFSH reference preparation from National Hormone and Pituitary Program from USA

Loureiro, Renan Fernandes 06 November 2006 (has links)
Um método de cromatografia líquida de alta eficiência por fase reversa (RP-HPLC) para análise qualitativa e quantitativa do hormônio folículo estimulante humano íntegro (hFSH), foi estabelecido e validado quanto à exatidão, precisão e sensibilidade. O FSH humano é um hormônio glicoprotéico dimérico largamente utilizado em medicina reprodutiva tanto para diagnóstico quanto para terapia. A metodologia desenvolvida preserva a integridade da proteína, permitindo a análise da forma heterodimérica intacta, e não somente de suas subunidades, como é normalmente obtida na maioria das condições geralmente empregadas. Esta técnica foi também utilizada para a comparação da hidrofobicidade relativa de preparações de hFSH hipofisária, urinária e derivadas de células de ovário de hamster chinês (CHO) bem como de outros dois hormônios glicoprotéicos, sintetizados na hipófise anterior: hormônio humano estimulante da tireóide (hTSH) e hormônio luteinizante humano (hLH). O menos hidrofóbico dos três hormônios analisados foi o hFSH, seguido do hTSH e do hLH. Uma diferença significativa (p<0,005) foi observada entre o tempo de retenção (tR) das preparações hipofisária e recombinante de hFSH, refletindo diferenças estruturais nas suas cadeias de carboidratos. Duas isoformas principais foram detectadas no hFSH urinário, incluindo uma forma que foi significativamente diferente (p<0,005) das preparações hipofisária e recombinante. Foram demonstradas linearidade da curva dose-resposta (r=0,9965, n=15) para esta metodologia de RP-HPLC, bem como uma precisão inter-ensaio, cujo coeficiente de variação é menor que 4%, para a quantificação de diferentes preparações de hFSH e uma sensibilidade da ordem de 40 ng. Foram também analisados o comportamento cromatográfico e a hidrofobicidade relativa das subunidades individuais das preparações recombinantes e hipofisária de hFSH. Além disso, a exata massa molecular das subunidades individuais de hFSH e do heterodímero foram simultaneamente determinadas por espectrometria de massa MALDI-TOF. A presente metodologia representa, em nossa opinião, uma ferramenta essencial para a caracterização e controle de qualidade deste hormônio, que ainda não consta das principais farmacopéias. / A reversed-phase high-performance liquid chromatography (RP-HPLC) method for the qualitative and quantitative analysis of intact human follicle-stimulating hormone (hFSH) was established and validated for accuracy, precision and sensitivity. Human FSH is a dimeric glycoprotein hormone widely used as a diagnostic analyte and as therapeutic product in reproductive medicine. The technique developed preserves the protein integrity, allowing the analysis of the intact heterodimeric form rather than just of its subunits, as it is the case for the majority of the conditions currently employed. This methodology has also been employed for comparing the relative hydrophobicity of pituitary, urinary and two Chinese hamster ovary (CHO)-derived hFSH preparations, as well as of two other related glycoprotein hormones of the anterior pituitary: human thyroid-stimulating hormone (hTSH) and human luteinizing hormone (hLH). The least hydrophobic of the three glycohormones analyzed was hFSH, followed by hTSH and hLH. A significant difference (p<0.005) was observed in tR between the pituitary and recombinant hFSH preparations, reflecting structural differences in their carbohydrate moieties. Two main isoforms were detected in urinary hFSH, including a form which was significantly different (p<0.005) for the pituitary and recombinant preparations. The linearity of the dose-response curve (r = 0.9965, n = 15) for this RP-HPLC methodology, as well as an inter-assay precision with relative standard deviation less than 4% for the quantification of different hFSH preparations and a sensitivity of the order of 40 ng, were demonstrated. The chromatographic behavior and relative hydrophobicity of the individual subunits of the pituitary and recombinant preparations were also analyzed. Furthermore, the accurate molecular mass of the individual hFSH subunits and of the heterodimer were simultaneously determined by matrix-assisted laser desorption ionization time-of-flight mass spectral analysis (MALDI-TOF-MS). The present methodology represents, in our opinion, an essential tool for characterization and quality control of this hormone that is not yet described in the main pharmacopoeias.
39

The Isolation and Electrochemical Studies of Flavanoids from Galenia africana and Elytropapus rhinocerotis from the North Western Cape

Maiko, Khumo Gwendoline January 2010 (has links)
<p>In this study two medicinal plant species, namely Galenia africana and Elytropapus rhinocerotis, the former belonging to the family Aizoceae and the latter belonging to the family Asteraceae, have been investigated and different compounds isolated and characterized. Both species are important plants used in traditional medicine in Africa and particularly in South Africa. Flavanoids are secondary metabolites found in plants. They have a protective function against UV radiation and have a defence against invading illnesses due to their important antioxidant activity. Much of the food we eat and some beverages we drink contain flavonoids. The aim of this study was to investigate the electrochemistry of flavanoids isolated from these species.</p>
40

The Isolation and Electrochemical Studies of Flavanoids from Galenia africana and Elytropapus rhinocerotis from the North Western Cape

Maiko, Khumo Gwendoline January 2010 (has links)
<p>In this study two medicinal plant species, namely Galenia africana and Elytropapus rhinocerotis, the former belonging to the family Aizoceae and the latter belonging to the family Asteraceae, have been investigated and different compounds isolated and characterized. Both species are important plants used in traditional medicine in Africa and particularly in South Africa. Flavanoids are secondary metabolites found in plants. They have a protective function against UV radiation and have a defence against invading illnesses due to their important antioxidant activity. Much of the food we eat and some beverages we drink contain flavonoids. The aim of this study was to investigate the electrochemistry of flavanoids isolated from these species.</p>

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