Thesis (M. S.)--Biology, Georgia Institute of Technology, 2006. / Donald Doyle, Committee Member ; Harish Radhakrishna, Committee Member ; Alfred Merrill, Committee Member ; Marion Sewer, Committee Chair Includes bibliographical references.

Proefschrift--Rijksuniversiteit te Utrecht. / Includes bibliographical references.

Undergraduate honors paper--Mount Holyoke College, 2005. Dept. of Biological Sciences. / Includes bibliographical references (leaves 74-79).

Thesis (Ph. D.)--University of Oregon, 2006. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 71-82). Also available for download via the World Wide Web; free to University of Oregon users.

Thesis (Ph.D.) -- University of Texas Southwestern Medical Center at Dallas, 2006. / Embargoed. Vita. Bibliography: 217-242.

Made available in DSpace on 2015-05-14T12:59:30Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 4079723 bytes, checksum: 557a5e2177144da21ce60f2cab677ba0 (MD5) Previous issue date: 2012-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Sargassum is a genus of brown seaweeds from the family Sargassaceae and is represented by 150 species. The literature reports the presence of alginates, phlorotanins, coumarins, chromones, quinones, phaeophitins and terpenoids. The metabolites produced by algae of the genus Sargassum show biological activities such as anticoagulant, antioxidant, antipyretic and analgesic. The objective of this study was to present phycochemical study of the species Sargassum vulgare var. nanum E. de Paula. The material was collected on the beach in Coqueirinho, Conde- PB, then was washed and lyophilized. The dried powder (841.19 g) was extracted by maceration with ethanol 96 oG.L, obtaining the crude extract (56.96 g) was dissolved in a solution H2O-MeOH (7:3) and partitioned with ethyl ether, dichloromethane and ethyl acetate. The ether extract (17.04 g) was subjected to silica gel chromatography column eluting with hexane, dichloromethane and ethyl and MeOH pure or in binary mixtures. The combined fractions (75-93) were subjected to chromatography with Sephadex LH-20 eluted with CH2Cl2-MeOH (1:1). The purified fraction Sv-1 was identified as fucosterol, the first reported in this specie. Other fractions (119-121 and 135.1) were subjected preparative thin layer chromatography (PTLC) with AcOEt-Hexane (25:75) and (40:60) to afford mixture -(132)-(R) and (132)-(S)-132-hydroxy-phaeophytin-a encoded as Sv-2 and 151-hydroxy-(151-S)-porphyrin lactone encoded as Sv-3. The R isomer of 132-hydroxy-phaeophytin-a is first reported in the genus and S isomer for the first time in this specie, while the porphyrin lactone is first reported in the family Sargassaceae. Structural elucidations were carried out based on the analysis of their 1H NMR and 13C NMR spectra and and on the basis of literature data. / Sargassum é um gênero de algas pardas da família Sargassaceae representada por 150 espécies. A literatura relata a presença de alginatos, florotaninos, cumarinas, cromonas, quinonas, feofitinas e terpenóides. Os metabólitos produzidos por algas do gênero Sargassum mostram atividades biológicas, tais como: anticoagulantes, antioxidante, antipirético e analgésica. O objetivo deste estudo foi apresentar estudo ficoquímico da espécie Sargassum vulgare var. nanum E. de Paula. O material foi coletado na praia de Coqueirinho, Conde-PB, e depois lavado e liofilizado. O pó seco (841,19 g) foi extraído por maceração com etanol a 96 oG.L, obtendo o extrato etanólico bruto (56,96 g) que foi dissolvido em uma solução de H2O-MeOH (7:3) e particionado com éter etílico, diclorometano e acetato de etila. O extrato etéreo (17,04 g) foi submetido a uma cromatografia em coluna de sílica gel, eluído com hexano, diclorometano e acetato de etila e MeOH puros ou em misturas binárias. As frações reunidas (75-93) foram submetidos a cromatografia em Sephadex LH-20 eluída com CH2Cl2-MeOH (1:1). A fração purificada Sv-1 foi identificado como fucosterol relatada pela primeira vez na espécie. As frações 119-121 e 135.1 foram submetidas cromatografia em camada delgada preparativa (CCDP) em AcOEt-hexano (25:75) e AcOEt-Hex (40:60) das quais foram possivel isolar duas feofitinas Sv-2 e Sv-3 identificada como a mistura de (132)-(R) e (132)-(S)-132-hidroxi-feofitina-a e 151-hidroxi-(151-S)-porfirinolactona a respectivamente. O isômero R da 132-hidroxi-feofitina-a é relatado pela primeira vez no gênero e o isômero S pela primeira vez na espécie, enquanto a porfirinolactona é relatada pela primeira vez na família Sargassarceae. As elucidações estruturais foram realizadas com base na análise de seus espectros de IV, RMN de 1H e 13C uni e bidimensionais e bem como com base em dados da literatura.

Cytochrome P-450, the terminal oxidase of the metabolic mono-oxygenase system, is thought to exist in multiple forms, which have differing substrate specificities, and are variably inducible by different enzyme inducers. Many mutagens, themselves unreactive, require metabolic activation by one or more of these cytochrome P-450-dependent microsomal enzymes for mutagenic activity. Such mutagens may be detected in the Salmonella mutagenicity test only by the incorporation of an hepatic microsomal (59) fraction into the assay (as a first approximation to in vivo metabolism). Induction of the microsomal enzymes by different agents enhances the metabolic activation of mutagens; in fact, many mutagens are only detected when the 59 fraction has been induced by appropriate agents. Inducers of the phenobarbital-type are known to enhance microsomal steroid hydroxylation when administered at supraphysiological levels, inducers of several mono-oxygenase activities. In turn, the steroids, have been reported to be The inductive effects of the female sex-steroids and the combined effects of steroid and phenobarbital (PB) pretreatment on the metabolic activation of four mutagens have been investigated using the Salmonella assay. Female Sprague-Dawley rats were pret reated with 17a-oestradiol (E2) or progesterone (PRG) , at a level of either 1 mg/kg or 20 mg / kg daily for 14 days. A duplicate set of similarly pretreated groups were also induced with PB. Hepatic microsomal fractions were prepared from each group and incubated with each of the te st mutagens in the presence of a tester strain known to detect each particular type of mutagen. Induction of the hepatic metabolizing system by PB increased the activation of the mutagens significantly (as reflected by an increased number of revertant prototrophic S .typhimurium colonies). The administration of PRG also caused significant, and dose-dependent, induction of the activation of af l atoxin B1, benzo(a)pyrene, and dimethylnitrosamine. In general, E2 exhibited no inductive effect, but it did produce an increase in the activation of aflatoxin B1 (a reaction which is known to be catalysed by a mono-oxygenase prefe rentially inducible by PB). When use was made of a microsomal fraction that was prepared from animals which were both steroidpretreated and induced by PB, mutagenic activation was of the same order of magnitude as that observed when induction was brought about by PB alone. The absence of additive effect, taken together with the observations already mentioned, indicate that steroids induce the same cytochrome isozymes that are induced by PB. The implications of sex-hormonal regulation of the metabolic activation of mutagens are briefly discussed. / KMBT_363 / Adobe Acrobat 9.53 Paper Capture Plug-in

Steroid hormone receptors (SHRs) are well validated therapeutic targets in a number of diseases. Current therapies competitively antagonise the ligand binding domain (LBD), blocking activation of the receptor and downstream signalling pathways. However cross-reactivity can be seen amongst the antagonists of different SHRs eliciting unwanted side effects. Additionally the acquisition of resistance to current therapies in diseases such as prostate cancer limits their use. The amino-terminal domain (NTD) of SHRs provides an alternative target for antagonism by allowing potential therapies to block receptor transactivation and inhibit interactions with co-activator proteins. Reduced homology between different SHR NTDs also increases the specificity of drug interactions. However development of targeted therapies using rational drug design has been hindered by its intrinsically disordered structure. Establishing cell lines which stably express a SHR responsive reporter gene alongside variants of SHRs lacking the LBD provides a method by which small molecules specifically targeting the NTD of each receptor can be identified. This assay has been designed to overcome the barriers to drug discovery that are presented by an intrinsically disordered protein. The project follows the design, development, optimisation and implementation of a high throughput screening assay with the potential to identify novel small molecule inhibitors of SHRs. The applications of these inhibitors are highlighted throughout, with specific reference to their potential to inhibit the androgen receptor in prostate cancer.

Made available in DSpace on 2014-06-11T19:29:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-27Bitstream added on 2014-06-13T20:59:35Z : No. of bitstreams: 1 fioratti_eg_me_botfmvz.pdf: 886721 bytes, checksum: 138629ffeb23e3040d4251bc7120ebe1 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo deste estudo foi verificar a influência da adição de antiinflamatórios esteróides (AIES) ao diluidor seminal na motilidade e funcionalidade espermática e a eficiência da dexametasona na imunomodulação da resposta inflamatória após a cobertura. A dexametasona foi selecionada entre quinze diferentes AIES. Foram analisadas a motilidade (CASA), a integridade da membrana plasmática e acrossomal e o potencial da membrana mitocondrial dos espermatozóides nos momentos zero, 30, 60 e 120 minutos após a diluição. A intensidade da reação inflamatória provocada pelo sêmen foi mensurada em éguas resistentes e susceptíveis à endometrite persistente pós cobertura utilizando exame ultrassonográfico e citologia exfoliativa do útero, concentração de neutrófilos e de óxido nítrico do fluído uterino e taxa de recuperação embrionária. Dentre os AIES testados a dexametasona foi a que apresentou menor efeito deletério sobre as caracteísticas de motilidade e na morfofuncionalidade espermática. Quinze éguas resistentes e 15 susceptíveis à endometrite persistente após cobertura foram submetidas ao tratamento com dexametasona sistêmica e intra uterina adicionada ao diluidor de sêmen. As éguas susceptíveis apresentaram resposta inflamatória mais intensa durante as primeiras 8 horas após a inseminação artificial (p<0,05), porém, após 24 horas as concentrações de óxido nítrico foram semelhantes entre as éguas resistentes e susceptíveis, apesar das éguas susceptíveis manterem a reação inflamatória mais intensa até esse momento (p<0,05). As taxas de recuperação embrionária foram maiores para as éguas resistentes do que para as susceptíveis (p<0,05). Os tratamentos com dexametasona não se mostraram eficazes na imunomodulação da resposta inflamatória induzida pela cobertura / The objective of this study was to assess the influence of the addition of anti-inflammatory steroids (AIS) in the seminal extender in sperm viability and functionality, and efficiency of dexamethasone on immune modulation of inflammatory response after mating. Dexamethasone was selected from fifteen different AIS. Motility, membrane and acrosomal integrity and mitochondrial membrane potential of spermatozoa in moments 0, 30, 60 e 120 minutes after dilution were analyzed. The intensity of the inflammatory reaction caused by sperm was measured in resistant and susceptible mares using ultrasound examination and exfoliative cytology of the uterus, concentration of neutrophils and nitric oxide in uterine fluid and rate of embryo recovery. Among the AIS tested dexamethasone maintained the sperm motility parameters and did not show any deleterious effects on sperm structure and function (p>0.05). Fifteen mares resistant and 15 susceptible to post-breeding endometritis were subjected to treatment with dexamethasone systemic and intra uterine added to the semen extender. Susceptible mares showed more severe inflammatory response during the first 8 hours after artificial insemination (p<0.05), while 24 hours after mating the concentrations of nitric oxide were similar between resistant and susceptible mares, despite the fact that susceptible mares presented inflammatory reaction more intensive in this moment (p<0.05). The embryo recovery rates were higher for mares resistant compared to susceptible (p<0.05). Treatments with dexamethasone were not effective in the immunomodulation of the inflammatory response induced by mating

Orientador: Luis Carlos Spolidório / Resumo: Hormônios esteroides sexuais participam de diversos eventos celulares e moleculares, e exercem influência sobre o epitélio e tecido conjuntivo do periodonto. A testosterona (T), principal hormônio androgênico, pode ser convertida em estradiol (E2) pela ação da enzima aromatase, ou em di-hidrotestosterona (DHT) pela ação da enzima 5α-redutase. Para elucidar o impacto de andrógenos sobre as células que compõem os tecidos conjuntivo e epitelial, fibroblastos e queratinócitos foram avaliados em relação aos efeitos de diferentes concentrações de T e DHT, além da exposição ao anastrozol (ANA), flutamida (FLU), fulvestranto (FUL), e às associações farmacológicas T+ANA, T+FLU e T+FUL. Os resultados do presente estudo indicaram que, de modo geral, hormônios esteroides androgênicos exercem efeitos opostos sobre eventos celulares de fibroblastos gengivais humano e células epiteliais HaCaT em cultura celular. Enquanto a T e a DHT agem promovendo o aumento da proliferação e atividade de fibroblastos, a exposição de células HaCaT a estes mesmos andrógenos resulta em inibição ou exiguidade do crescimento celular, atividade metabólica ou a capacidade de repovoamento da área de arranhão in vitro. Além disso, o tratamento farmacológico com ANA, FLU, FUL, e suas respectivas associações à T, parece influenciar eventos celulares de fibroblastos gengivais humano e células epiteliais HaCaT in vitro. / Abstract: Sex steroid hormones take part in different cellular and molecular process and exert their functions on the epithelium and connective tissue of the periodontium. Testosterone (T), the main androgenic hormone can be converted to estradiol (E2) through the aromatase enzyme action, or into dihydrotestosterone (DHT) by 5α-reductase activity. To elucidate the impact of androgens on the cells that constitute the connective and epithelial tissues, fibroblasts and keratinocytes were evaluated under the effects of different concentrations of T and DHT, besides to be both exposed to anastrozole (ANA), flutamide (FLU), fulvestrant (FUL), and the pharmacological associations T+ANA, T+FLU and T+FUL. The results of this study indicated that, in general, androgenic steroid hormones exert opposite effects on cellular events of human gingival fibroblasts and epithelial cells. While androgens act stimulating gingival fibroblasts, in HaCaT cells androgens promotes a shortage or inhibition of cell growth and activity. Furthermore, pharmacological treatment with ANA, FLU, FUL, and their associations to T, appears to influence cellular events of human gingival fibroblasts and HaCaT cells in vitro. / Mestre