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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

Compostos de ferro de interesse farmacológico: avaliação da estabilidade, toxicidade em organismos aquáticos, transporte em células e capacidade de gerar reservatórios de ferro lábil / Iron compound of pharmacological interest: evaluation of stability, toxicity against aquatic organisms, transport in cells and capacity to generate labile iron pool

Vitorino, Hector Aguilar 07 December 2015 (has links)
A sobrecarga de ferro é uma condição desfavorável tanto para humanos (portadores de disfunções no metabolismo desse metal, ou submetidos a intensos regimes de transfusão) como, possivelmente, para os organismos aquáticos. Metalofármacos de ferro compreendem agentes anti-hipertensivos, anti-microbianos e suplementos minerais; mais recentemente, o uso de nanomateriais magnéticos à base de ferro vem sendo proposto para diversas aplicações clínicas ou farmacológicas. Contudo, os possíveis danos por sobrecarga induzida desses compostos não são totalmente compreendidos tanto para humanos e no ambiente aquático. Neste trabalho se usaram fármacos comerciais com diferentes revestimentos, de uso animal e humano, obtidos de diferentes indústrias brasileiras. Também se sintetizaram derivados de ferroceno (Fc) (TMH-Fc, TMH2-Fc), e nanopartículas magnéticas solúveis em água de três tamanhos (5,8,12 nm) pelo método de decomposição térmica a partir do Fe(acac)3. Em seguida, se avaliou a estabilidade dos metalofármacos de ferro em meios fisiologicamente relevantes, frente a sideróforos e/ou moléculas envolvidas no transporte do metal (CAL, Fl-Tf, Fl-DFO), mostrando disponibilidade de ferro só para os derivados de Fc a pH 7,4. A capacidade de geração de espécies reativas de oxigênio, medida por oxidação da DHR, foi detectada só para os derivados de Fc e nanomaterias. Um teste de toxicidade em Artemia salina de primeiro estágio foi positivo para o TMH-Fc (LC50 76,7 µM). Finalmente se estudou a capacidade de estocagem de ferro em células epiteliais de hepatopâncreas do caranguejo de mangue Ucides cordatus, em diferentes etapas de desenvolvimento (E, R, F e B). Todas mostraram transporte de metalofármacos e nanomaterias, e só os tipos celulares F e B incorporaram os derivados de Fc. Vários dos compostos de ferro estudados, com aplicações principalmente farmacológicas, poderiam ser disponibilizados no meio ambiente, principalmente no aquático. Os nossos resultados mostram que a capacidade de disponibilizar ferro e de gerar EROs podem ser quantificadas eficazmente por métodos de fluorescência. Além disso, sua possível toxicidade pode ser monitorada no meio marinho por bioindicadores de toxicidade e de acúmulo de metais. / Iron overload is an unfavorable condition for both humans (patients with disorders in the metabolism of the metal, or subjected to intense transfusion) and possibly to aquatic organisms. Iron metallodrugs include antihypertensive agents, antimicrobial and mineral supplements. More recently, the use of magnetic iron based nanomaterials has been proposed for various clinical or pharmacological applications. However, possible overload damage induced by these compounds is not fully understood for both humans and aquatic organisms. For this work, we used commercial drugs with different coatings, for animal and human use, obtained from different Brazilian industries. Also we synthesized ferrocene (Fc) derivatives (TMH-Fc TMH2-Fc) and water soluble magnetic nanoparticles in three different sizes (5,8,12 nm) by the thermal decomposition method from Fe(acac)3. We evaluated the stability of iron metallodrugs in physiologically relevant medium against siderophores and/or molecules involved in metal transport (CAL, Fl-Tf, Fl-DFO), where we found iron availability only for ferrocene derivatives at pH 7.4. The ability to generate reactive oxygen species was measured by oxidation of DHR, and was present in the ferrocene derivative and nanomaterials. A toxicity assay on first stage Artemia salina was positive for TMH-Fc (LC50 76.7 µM). Finally, we studied the iron storage capacity of hepatopancreatic cells of a mangrove crab, Ucides cordatus, at different stages of development (E, R, F and B). All displayed transport of metallodrugs and nanomaterials, and only the cell types F and B incorporated ferrocene derivatives. Several of the iron compounds studied, particularly of pharmaceutical application, could be made available in the environment, especially in water. Our results show that the ability to supply iron and to generate ROS can be effectively quantified by fluorescence methods. In addition, their possible toxicity can be monitored in the marine environment with biomarkers of toxicity and accumulation of metals.
32

PurificaÃÃo, caracterizaÃÃo fÃsico-quÃmica e biolÃgica de SLA: uma nova lectina extraÃda de sementes de Swartzia laevicarpa Amshoff / Purification, physico-chemical and biological characterization of SLA: a new lectin extracted from seeds of Swartzia laevicarpa Amshoff

Rafael da ConceiÃÃo SimÃes 20 June 2013 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Lectinas sÃo proteÃnas de origem nÃo imune que possuem pelo menos um domÃnio de ligaÃÃo especÃfica e reversÃvel a carboidratos, sem aÃÃo enzimÃtica. Estas proteÃnas sÃo amplamente distribuÃdas na natureza. As lectinas isoladas de sementes de leguminosas estÃo entre as mais estudadas e possuem homologia, sendo importantes marcadores moleculares da evoluÃÃo dentro desta famÃlia vegetal. Existem poucas informaÃÃes sobre as lectinas das tribos da base da subfamÃlia Papilionoideae e novas informaÃÃes sÃo importantes para solidificar os conhecimentos sobre as lectinas dessas tribos. Este trabalho teve como objetivo purificar uma nova lectina de sementes de Swartzia laevicarpa, caracteriza-la fÃsicoquimicamente e por espectrometria de massas e testa-la quanto a sua capacidade de causar inflamaÃÃo e dor e quanto a sua toxidade contra nÃuplios de Artemia sp. A lectina foi purificada por fracionamento por sulfato de amÃnio seguido de cromatografia de troca iÃnica e exclusÃo molecular. Denominada de SLA, a lectina apresenta o perfil eletroforÃtico de uma cadeia de 30 kDa e, diferente de SLL, apresenta subunidades por volta de 13 e 17 kDa. Possui afinidade por GalNAc e derivados de galactose, e apresenta caracterÃsticas termodinÃmicas de ligaÃÃo diferente para Gal e GalNAc. A lectina em estudo causou inflamaÃÃo em modelo de edema de pata de camundongos e hipernocicepÃÃo ligada a inflamaÃÃo. SLA tambÃm apresentou toxicidade contra nÃuplios de fase II de Artemia sp. A lectina isolada e caracterizada nesse trabalho demonstra ser uma ferramenta taxonÃmica interessante para corroborar o posicionamento de Swartzeae alÃm de demonstrar tambÃm um potencial biotecnolÃgico no estudo de modelos de inflamaÃÃo e dor. AtravÃs da espectrometria de massas foi possÃvel verificar que SLA apresenta pelo menos duas isoformas e apresenta glicoformas. Possui aproximadamente 250 resÃduos de aminoÃcidos e nesse trabalho foram determinados 179 deles. SLA apresentou similaridade com lectinas de outras tribos basais como VML e SJA, corroborando com a classificaÃÃo de Swartzieae como tribo de Papilionoideae e demonstrando a utilizaÃÃo de lectinas como ferramenta taxonÃmica. / Lectins are proteins of non-immune origin that have at least one specific and reversible carbohydrate binding domain without enzymatic action. These proteins are widely distributed in nature. Lectins isolated from legume seeds are among the most studied, have homology and are important markers of evolution within this plant family. There is little information about the lectins of the basal tribes of the subfamily Papilionoideae and new information is important to solidify your knowledge of the lectins of these tribes. This study aimed to purify a new lectin from Swartzia laevicarpa, to characterize its physical-chemical and mass spectrometry proprieties and test as its ability to cause inflammation and pain and their toxicity against Artemia sp. The lectin was purified by ammonium sulfate fractionation followed by ion exchange chromatography and molecular exclusion. Named SLA, the lectin shows the electrophoretic profile of a chain of 30 kDa and, unlike SLL presents subunits around 13 and 17 kDa. Has affinity for GalNAc and Gal derivatives, and presents thermodynamic binds characteristics of different for Gal and GalNAc. SLA caused inflammation in a model of paw edema of mice and hypernociception linked to inflammation. SLA also showed toxicity against stage II nauplii of Artemia sp. The lectin isolated and characterized in this work proves to be an interesting tool and corroborate the taxonomic placement of Swartzeae. SLA also demonstrate the biotechnological potential in the study of models from inflammation and pain. By mass spectrometry we found that SLA has at least two isoforms and provides glycoforms. It has approximately 250 amino acid residues and in this work were determined 179 of them. SLA showed similarity with lectins from other basal tribes as VML and SJA, corroborating the classification as Swartzieae Papilionoideae tribe and demonstrating the use of lectins as a taxonomic tool.
33

Biotic challenges for extremophiles : reproductive interference and parasite specialization in Artemia / Des défis biotiques pour des extrêmophiles : l'interférence reproductive et la spécialisation parasitaire chez Artemia

Lievens, Eva J.P. 12 December 2016 (has links)
Les défis posés par des facteurs biotiques – les interactions avec des compétiteurs, des parasites, etc. – jouent un rôle important dans l’évolution des populations, mais sont souvent difficiles à étudier. Dans cette étude, nous avons utilisé le système biologique Artemia dans les salins d’Aigues-Mortes, France, pour étudier le caractère et l’évolution de plusieurs interactions interspécifiques. Le système est particulièrement bien adapté à cette recherche : il est simple, contenant deux espèces d’Artemia, trois parasites fortement prévalents (un helminthe et deux microsporidies), et des microbiota variés ; et beaucoup des interactions du système ont été nouvellement établies, car une des espèces d’Artemia est invasive. Nous avons étudié deux types d’interactions. Premièrement, la présence et l’évolution de l’interférence reproductive entre les espèces native et invasive d’Artemia. Nous avons trouvé que l’espèce invasive, qui est sexuée, subit une interférence sévère en allocation des sexes en présence de l’espèce native et asexuée, mais pas d’interférence en gardiennage de partenaire. Deuxièmement, l’évolution de la spécialisation de deux parasites microsporidiennes qui infectent les espèces d’Artemia. En nous basant sur des données de terrain, des infections expérimentales, et de l’évolution expérimentale, nous avons investigué l’état, les causes, et les conséquences de la spécialisation des microsporidies. Les résultats démontrent que les microsporidies sont spécialisées dans l’utilisation d’une des espèces d’hôte, même si elles sont capables de compléter leur cycle de vie dans chacun des deux hôtes. Cette spécialisation paraît être imposée par les outils précis nécessaires à l’exploitation de chaque hôte ; dans les hôtes non-spécialistes, ils provoquaient de l’exploitation sous-optimale, de la virulence maladaptative, et de l’immunopathologie. En général, ces études suggèrent que les facteurs biotiques imposent des pressions de sélection fortes sur Artemia, auxquelles elles ne peuvent pas toujours répondre facilement. L’importance des facteurs biotiques dans un système qui est autrement dominé par des conditions abiotiques extrêmes souligne l’importance des interactions interspécifiques dans l’évolution. / The challenges posed by biotic factors – interactions with competitors, parasites, etc. – play a large role in the evolution of populations, but are generally difficult to study. In this work, we used the Artemia system in the hypersaline salterns of Aigues-Mortes, France, to study the character and evolution of several interspecific interactions. The system is eminently suited to such studies: it is simple, containing two Artemia species, three highly prevalent parasites (one helminth and two microsporidians), and various microbiota; and many of its interactions are newly-established, because one of the Artemia species is invasive. We studied two types of interactions. First, the presence and evolution of reproductive interference between the native and invasive Artemia species. We found that the invasive Artemia species, which is sexual, undergoes severe interference in sex allocation when in the presence of the native, asexual Artemia, but no interference in mate guarding. Second, the evolution of parasite specialization in two microsporidian parasites infecting the Artemia species. Using field data, experimental infections, and experimental evolution, we investigated the state, causes, and consequences of specialization in the microsporidians. Results consistently indicated that the microsporidians are specialized for one host species, despite being able to complete their life cycle in either host. This specialization appears to be imposed by the precise toolkits needed to exploit each host species; in the non-specialized hosts, these triggered suboptimal exploitation, maladaptive virulence, and immunopathology. Overall, these studies suggest that the biotic factors acting on Artemia impose strong selection pressures, to which they cannot always respond easily. The importance of biotic factors in a system which is otherwise dominated by extreme abiotic conditions underlines the importance of species interactions in shaping evolution.
34

Compostos de ferro de interesse farmacológico: avaliação da estabilidade, toxicidade em organismos aquáticos, transporte em células e capacidade de gerar reservatórios de ferro lábil / Iron compound of pharmacological interest: evaluation of stability, toxicity against aquatic organisms, transport in cells and capacity to generate labile iron pool

Hector Aguilar Vitorino 07 December 2015 (has links)
A sobrecarga de ferro é uma condição desfavorável tanto para humanos (portadores de disfunções no metabolismo desse metal, ou submetidos a intensos regimes de transfusão) como, possivelmente, para os organismos aquáticos. Metalofármacos de ferro compreendem agentes anti-hipertensivos, anti-microbianos e suplementos minerais; mais recentemente, o uso de nanomateriais magnéticos à base de ferro vem sendo proposto para diversas aplicações clínicas ou farmacológicas. Contudo, os possíveis danos por sobrecarga induzida desses compostos não são totalmente compreendidos tanto para humanos e no ambiente aquático. Neste trabalho se usaram fármacos comerciais com diferentes revestimentos, de uso animal e humano, obtidos de diferentes indústrias brasileiras. Também se sintetizaram derivados de ferroceno (Fc) (TMH-Fc, TMH2-Fc), e nanopartículas magnéticas solúveis em água de três tamanhos (5,8,12 nm) pelo método de decomposição térmica a partir do Fe(acac)3. Em seguida, se avaliou a estabilidade dos metalofármacos de ferro em meios fisiologicamente relevantes, frente a sideróforos e/ou moléculas envolvidas no transporte do metal (CAL, Fl-Tf, Fl-DFO), mostrando disponibilidade de ferro só para os derivados de Fc a pH 7,4. A capacidade de geração de espécies reativas de oxigênio, medida por oxidação da DHR, foi detectada só para os derivados de Fc e nanomaterias. Um teste de toxicidade em Artemia salina de primeiro estágio foi positivo para o TMH-Fc (LC50 76,7 µM). Finalmente se estudou a capacidade de estocagem de ferro em células epiteliais de hepatopâncreas do caranguejo de mangue Ucides cordatus, em diferentes etapas de desenvolvimento (E, R, F e B). Todas mostraram transporte de metalofármacos e nanomaterias, e só os tipos celulares F e B incorporaram os derivados de Fc. Vários dos compostos de ferro estudados, com aplicações principalmente farmacológicas, poderiam ser disponibilizados no meio ambiente, principalmente no aquático. Os nossos resultados mostram que a capacidade de disponibilizar ferro e de gerar EROs podem ser quantificadas eficazmente por métodos de fluorescência. Além disso, sua possível toxicidade pode ser monitorada no meio marinho por bioindicadores de toxicidade e de acúmulo de metais. / Iron overload is an unfavorable condition for both humans (patients with disorders in the metabolism of the metal, or subjected to intense transfusion) and possibly to aquatic organisms. Iron metallodrugs include antihypertensive agents, antimicrobial and mineral supplements. More recently, the use of magnetic iron based nanomaterials has been proposed for various clinical or pharmacological applications. However, possible overload damage induced by these compounds is not fully understood for both humans and aquatic organisms. For this work, we used commercial drugs with different coatings, for animal and human use, obtained from different Brazilian industries. Also we synthesized ferrocene (Fc) derivatives (TMH-Fc TMH2-Fc) and water soluble magnetic nanoparticles in three different sizes (5,8,12 nm) by the thermal decomposition method from Fe(acac)3. We evaluated the stability of iron metallodrugs in physiologically relevant medium against siderophores and/or molecules involved in metal transport (CAL, Fl-Tf, Fl-DFO), where we found iron availability only for ferrocene derivatives at pH 7.4. The ability to generate reactive oxygen species was measured by oxidation of DHR, and was present in the ferrocene derivative and nanomaterials. A toxicity assay on first stage Artemia salina was positive for TMH-Fc (LC50 76.7 µM). Finally, we studied the iron storage capacity of hepatopancreatic cells of a mangrove crab, Ucides cordatus, at different stages of development (E, R, F and B). All displayed transport of metallodrugs and nanomaterials, and only the cell types F and B incorporated ferrocene derivatives. Several of the iron compounds studied, particularly of pharmaceutical application, could be made available in the environment, especially in water. Our results show that the ability to supply iron and to generate ROS can be effectively quantified by fluorescence methods. In addition, their possible toxicity can be monitored in the marine environment with biomarkers of toxicity and accumulation of metals.
35

Biotechnological potential of lectins: induction of apoptosis in A549 cells, pro-healing effects on experimental wounds and cell toxicity analysis on Artemia sp. / Potencial biotecnolÃgico de lectinas: induÃÃo de apoptose em cÃlulas A549, efeito prÃ-cicatrizante em feridas experimentais e anÃlise de toxicidade sobre Artemia sp.

Francisco Vassiliepe Sousa Arruda 29 November 2011 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / This work evaluated the biotechnological potential of lectins in the induction of apoptosis of neoplastic cells; the effect on wound healing in a murine model (in vivo) and established the level of toxicity on Artemia sp. Lectins are proteins or glycoproteins ubiquitously distributed in nature, being found from bacteria to humans. Since carbohydrates can act as mediators of biological information, the interaction with lectins can trigger some biologically important effect. To verify the role of lectins in the induction of apoptosis, A549 cells (lung carcinoma) were grown for 1 hour with lectins isolated from seeds of Canavalia ensiformis (ConA), C. brasiliensis (ConBr), C. boliviana (ConBol), C. grandiflora (Cgran) and C. gladiata (CGL) labeled with FITC. In addition, the relative gene expression of p53, Bax, Bcl-2 and caspase 9 was also evaluated when the cells were cultured with ConA, ConBr and ConBol. The data showed that all lectins interacted with A549 cells. Nevertheless, p53 and Bax had no significant change. Unlike, the expression of BCL-2 was down-regulated while caspase 9 was up-regulated by treatment with lectins. Concerning the pro-healing potential, the lectin isolated from the red alga Bryothamnion seafortii (BS) was tested by topical treatment of skin lesions. The data showed that BS improved the quality of healing, probably through the induction of fibroblast proliferation. Finally, the lethality test of Artemia sp. was carried out to determine the toxicity of some Diocleinae lectins. ConBr is the most toxic lectin against Artemia, while ConA is the least toxic, and ConBol, ConM, ConGr and CGL exhibit intermediate levels of toxicity. / Este trabalho avaliou o potencial biotecnolÃgico de lectinas na induÃÃo da apoptose de cÃlulas neoplÃsicas, o efeito sobre a cicatrizaÃÃo de feridas em modelo murino (in vivo) e estabeleceu o nÃvel de toxicidade sobre Artemia sp. Lectinas sÃo proteÃnas ou glicoproteÃnas distribuÃdas ubiquamente na natureza, sendo encontradas desde bactÃrias atà seres humanos. Tais proteÃnas possuem a capacidade de ligar-se seletivamente a carboidratos. Considerando que carboidratos possam atuar como mediadores da informaÃÃo biolÃgica, a sua interaÃÃo com lectinas pode desencadear algum efeito biolÃgico importante. Para verificar o papel das lectinas sobre a induÃÃo da apoptose, cÃlulas A549 (carcinoma de pulmÃo) foram cultivadas durante 1 hora juntamente com lectinas isoladas das sementes de Canavalia ensiformis (ConA), C. brasiliensis (ConBr), C. boliviana (ConBol), C. grandiflora (Cgran) e C. gladiata (CGL) marcadas com FITC. Em adiÃÃo, a expressÃo gÃnica relativa de p53, Bax, BCL-2 e caspase 9 foi tambÃm avaliada quando as cÃlulas foram cultivadas com ConA, ConBr e ConBol. Os dados mostraram que todas as lectinas intergiram com as cÃlulas A549. NÃo obstante, p53 e Bax nÃo tiveram nenhuma alteraÃÃo significativa. PorÃm, BCL-2 teve sua expressÃo diminuÃda enquanto a da caspase 9 foi aumentada pelo tratamento com as lectinas. Com relaÃÃo ao potencial pro-cicatrizante, a lectina isolada da alga vermelha Bryothamnion seafortii (BS) foi testada atravÃs do tratamento tÃpico de lesÃes cutÃneas. Os dados mostraram que BS melhora a qualidade da cicatrizaÃÃo, muito possivelmente atravÃs da induÃÃo da proliferaÃÃo de fibroblastos. Por fim, o teste de letalidade sobre Artemia sp. foi utilizado para verificar a toxicidade de algumas lectinas da subtribo Diocleinae. Os resultados mostraran que ConBr e ConA sÃo as lectinas mais tÃxica e menos tÃxica, respectivamente. ConBol, ConM, Cgran e CGL exibiram nÃveis intermediÃrios de toxicidade.
36

DESENVOLVIMENTO, CARACTERIZAÇÃO, ESTUDOS DE ESTABILIDADE, GENOTOXICIDADE, CITOTOXICIDADE E ECOTOXICIDADE DE SISTEMAS NANOESTRUTURADOS CONTENDO ÓLEO ESSENCIAL DE GENGIBRE OU TRANS-ANETOL

Pinto, Cláudia Grigolo 27 March 2018 (has links)
Submitted by MARCIA ROVADOSCHI (marciar@unifra.br) on 2018-08-20T13:06:20Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_ClaudiaGrigoloPinto.pdf: 2951768 bytes, checksum: d150d2a4b45b72a14b6089d1bcad085b (MD5) / Made available in DSpace on 2018-08-20T13:06:20Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_ClaudiaGrigoloPinto.pdf: 2951768 bytes, checksum: d150d2a4b45b72a14b6089d1bcad085b (MD5) Previous issue date: 2018-03-27 / This study explored the profile of the ginger essential oil and of the trans-anethole, which are medicinal plants active ingredients extensively used in traditional medicine. These have been popularized in recent years, due to several properties, which are, however, significantly toxic. These ingredients were manipulated by methods used in nanotechnology. Thus, lipid- and polymer-based nanostructure systems, such as nanocapsules, nanoemulsions, and lipid carriers were produced. For the polymer systems, a preliminary study was carried out in order to determine which polymer would be used, which was later tested using a polymer swelling test. After the definition of the polymer and of the best methodology, the systems were produced. These had their physical-chemical parameters, such as polydispersity index, zeta potential, mean particle diameter, pH and stability evaluated for 90 days to verify in which conditions they were stable, thus allowing the determination of the best storage conditions. Nanocapsules, nanoemulsions, and lipid carriers containing ginger essential oil were produced. Similarly, systems which contained trans-anethole were produced. For comparison purposes, blank systems, which do not have the studied ingredients, were also produced. After characterization and stability studies, each of the systems was analyzed for the following: cytotoxicity and cell viability in macrophages by the MTT assay, genotoxicity by the Comet assay, antimicrobial activity by disk diffusion, antimicrobial activity by broth microdilution, and ecotoxicity by bioassay with Artemia. As for the antimicrobial activity, only some of the formulations presented significant activity on the analyzed strains. In general, the results obtained indicated a reduction in the cyto-, geno- and the eco-toxicity of the nanostructured systems when compared with the free forms of the studied ingredients and their respective controls. This study made it possible to corroborate other studies which have also demonstrated the great potential of the use of nanotechnology to explore the profile of medicinal plants. Through these methodologies, their toxicity could be reduced and pharmacological and environmental safety could be promoted. Considering the results obtained, four scientific articles were produced and submitted to scientific journals. / O óleo essencial de gengibre e o trans-anetol, que são ativos oriundos de plantas medicinais com extensa utilização na medicina tradicional os quais tiveram sua popularização nos últimos anos, sendo relacionados a várias propriedades, que, no entanto, apresentam toxicidade bastante significativa. Através de métodos empregados na Nanotecnologia foram produzidos sistemas nanoestruturados poliméricos e de base lipídica, no caso, nanocápsulas, nanoemulsões e carreadores lipídicos. Para os sistemas poliméricos, foi realizado um estudo preliminar para a escolha do polímero que seria utilizado. Este estudo empregou o teste do inchamento do polímero. Após a definição do polímero e da melhor metodologia, os sistemas foram produzidos e tiveram seus parâmetros físico-químicos, como índice de polidisperssão, potencial zeta, diâmetro médio de partículas, pH e a estabilidade avaliados por 90 dias para verificar em que condições permaneciam estáveis, possibilitando determinar as melhores condições de armazenamento. Foram produzidas nanocápsulas, nanoemulsões e carreadores lipídicos contendo óleo essencial de gengibre e as mesmas categorias de sistemas contendo trans-anetol. Para fins de comparação, também foram produzidos sistemas brancos, ou seja, nanocápsulas, nanoemulsões e carreadores lipídicos sem os ativos de estudo. Após os estudos de caracterização e de estabilidade, cada um dos sistemas foi analisado em relação às seguintes atividades: citotoxicidade e viabilidade celular pelo ensaio MTT, genotoxicidade pelo ensaio Cometa, atividade antimicrobiana por disco-difusão, atividade antimicrobiana por microdiluição em caldo e atividade ecotóxica por bioensaio com artêmias. Quanto à atividade antimicrobiana, apenas os tratamentos com óleo de gengibre livre apresentaram atividade significativa sobre as cepas de E. coli, P. aeruginosa, S. aureus e C. albicans. Os resultados obtidos, conforme objetivo proposto apontaram redução da cito, geno e ecotoxicidade dos sistemas nanoestruturados testados quando comparados com as formas livres dos ativos estudados e com seus respectivos controles, o que tornou possível corroborar com outros estudos que também demonstram o grande potencial do uso de Nanotecnologia para explorar o perfil de ativos oriundos de plantas medicinais, que, mediante essas metodologias, reduzem a toxicidade, promovendo a segurança farmacológica e ambiental para a utilização dos mesmos. Diante dos resultados obtidos, quatro artigos científicos foram produzidos e submetidos a revistas científicas para divulgação.
37

Estudo químico e biológico dos constituintes do Cerne de Abuta Refescens AUBL. (Menispermaceae)

Albuquerque, Vanessa Homobono Santa Brígida de 19 October 2004 (has links)
Made available in DSpace on 2015-04-22T22:01:52Z (GMT). No. of bitstreams: 1 Vanessa Homobono Santa Brigida de Albuquerque.pdf: 2068823 bytes, checksum: f4287d8860ffadfb930d9adb010eeefd (MD5) Previous issue date: 2004-10-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The bôta, Abuta rufescens Aubl. (MENISPERMACEAE), is a medicinal plant used popularly in the treatment of malaria, uterine inflammations, hepatic illnesses and gastric ulcer, besides having action as antimycotic, diuretic and abortive. Previous chemical studies had disclosed to the presence in its stem of oxoaporphines and azafluoranthenes alkaloids. Of the chromatographic fractionate of the extract of stem in dichloromethane it was isolated, from chromatographic techniques, a crystal in form of orange needles that was identified through spectrometric methods (IR, MS, 13C NMR, 1H NMR) as the Homomoschatoline alkaloid. This work tells the gotten results of the toxicity evaluation of this alkaloid by the bioessay in Artemia franciscana, and of antitumoral activity with ancestries of cells of human breast tumors (Mcf-7), of human colon (Hct-8), of promielocitic human leukemia (Hl-60) and tumor skin (B-16). / A bôta, Abuta rufescens Aubl. (MENISPERMACEAE), é uma planta medicinal usada popularmente no tratamento da málaria, de inflamações uterinas, de doenças hepáticas e úlcera gástrica, além de ter ação como antimicótico, diurético e abortivo. Estudos químicos anteriores revelaram a presença em seu caule de alcalóides oxoaporfínicos e azafluorantenos. A partir do fracionamento cromatográfico do extrato do cerne em diclorometano isolou-se, através de técnicas cromatográficas, um cristal em forma de agulhas alaranjadas que foi identificado por métodos espectrométricos (IV, EM., RMN de 13C, RMN de 1H) como o alcalóide Homomoschatolina. Este trabalho relata os resultados obtidos da avaliação da toxicidade deste alcalóide pelo bioensaio em Artemia franciscana, e de atividade antitumoral com linhagens de células de tumores de mama humano (MCF-7), de cólon humano (HCT-8), de leucemia promielocítica humana (HL-60) e pele murino (B-16).
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The Economics of Partial Artemia Replacement Using Two Commercially Available Feeds in the Diets of Litopenaeus vannamei from Z3/M1 – PL10

Giguere, Monique A 01 December 2011 (has links)
The purpose of this study was twofold: 1) to identify commercially available feeds that could serve as suitable replacements for newly hatched Artemia in the diets of L. vannamei from Z3/M1 to PL10 without significantly affecting survival, final length and weight, and quality of the larvae and 2) to identify an ideal substitution rate between live Artemia and a replacement feed that maximizes feed and labor costs savings, survival, and PL quality. In Experiment 1, two commercially available Artemia replacement feeds, Zeigler EZ Artemia and Bernaqua Vitellus, were administered according to manufacturer’s guidelines in order to identify which feed served as a more suitable replacement diet. In Experiment 2, the more successful feed from Experiment 1 was administered in three different co-feeding strategies, in which the inert feed replaced a certain percentage of live Artemia. Mean percent survival was not significantly different between the Control, EZ Artemia, and Vitellus treatment groups in Experiment 1 (P<0.05). Both the EZ Artemia and Vitellus treatments yielded significantly different final mean lengths (mm) and weights (mg) from the Control group. The Vitellus feed results for all performance factors (mean percent survival, final length (mm), final weight (mg), and percent stress test mortality) were not significantly different than those of the EZ Artemia treatment, despite receiving no Artemia during the culture period, while the EZ Artemia treatment received 75% Artemia from PL5-PL10. For these reasons, the Vitellus feed was selected as the more successful feed in Experiment 1. In Experiment 2, there was no significant difference between the four treatment groups (Control, V50, V100/50, and V100/75) for mean percent survival and percent stress test mortality (P<0.05). The V100/50 and V100/75 treatments’ mean final lengths (mm) and weights (mg) were significantly different than those of the Control treatment. There were no significant differences between the V50, V100/50, and V100/75 treatments for any of the observed performance factors. These results indicate that the maximum substitution rate of Vitellus for Artemia in this experiment (the V100/75 treatment) was successful in replacing 84.33% of newly hatched Artemia in the larval culture of L. vannamei from Z3/M1-PL10 without resulting in significantly different survival and stress test mortalities compared to the Control group. Feeding schedules such as V100/75 treatment help streamline production efforts in commercial operations and result in increased production cost savings when compared to other replacement feeding schedules that begin in the early mysis stages. The V100/75 feeding schedule influences variable feed and labor costs the greatest because farmers are able to delay the culturing of Artemia an additional 7 days (until PL5) from what is typically performed in larviculture facilities.
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Food and feeding of the brine shrimp Artemia franciscana (Brazilian "Macau" population) in semi-intensive culture /

Campos, Alberto Alves, January 2000 (has links)
Thesis (M.Sc.), Memorial University of Newfoundland, 2000. / Bibliography: leaves 98-111.
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Enrichment of live feeds with various oil emulsions : effects on yellowtail flounder larvae, and on rotifers and brine shrimp /

Metusalach, January 2002 (has links)
Thesis (Ph.D.)--Memorial University of Newfoundland, 2002. / Includes bibliographical references.

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