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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.
851

Mechanistic approaches towards understanding particle formation in biopharmaceutical formations : the role of sufactant type and level on protein conformational stability, as assessed by calorimetry, and on protein size stability as assessed by dynamic light scattering, micro flow imaging and HIAC

Vaidilaite-Pretorius, Agita January 2013 (has links)
Control and analysis of protein aggregation is an increasing challenge to biopharmaceutical research and development. Therefore it is important to understand the interactions, causes and analysis of particles in order to control protein aggregation to enable successful biopharmaceutical formulations. This work investigates the role of different non-ionic surfactants on protein conformational stability, as assessed by HSDSC, and on protein size stability as assessed by Dynamic Light Scattering (DLS), HIAC and MFI. BSA and IgG2 were used as model proteins. Thermal unfolding experiments indicated a very weak surfactant-immunoglobulin IgG2 interaction, compared to much stronger interactions for the BSA surfactant systems. The DLS results showed that BSA and IgG2 with different surfactants and concentration produced different levels of particle size growth. The heat treatment and aging of samples in the presence of Tween 20, Tween 80, Brij 35 and Pluronic F-68 surfactants led to an increase in the populations of larger particles for BSA samples, whereas IgG2 systems did not notably aggregate under storage conditions MFI was shown to be more sensitive than HIAC technique for measuring sub-visible particles in protein surfactant systems. Heat treatment and storage stress showed a significant effect on BSA and IgG2 protein sub-visible particle size stability. This work has demonstrated that both proteins with different Tween 20, Tween 80, Brij 35 and Pluronic F-68 concentrations, have different level of conformational and size stability. Also aging samples and heating stress bears the potential to generate particles, but this depends on surfactant type. Poor predictive correlations between the analytical methods were determined.
852

Perfil de ativação de basófilos e evidência de fatores liberadores de histamina na urticária crônica idiopática / Basophils activation profile and evidence of histamine release factor in Chronic Idiopathic Urticaria

Francinelson Duarte Lourenço 07 December 2009 (has links)
INTRODUÇÃO: A Urticária Crônica é caracterizada pelo aparecimento de pápulas eritematosas, pruriginosas recorrentes e transitórias que duram por mais de seis semanas. Na maioria dos pacientes a causa é indeterminada, definida como idiopática (UCI), entretanto, um sub-grupo apresentam autoanticorpos contra a cadeia alfa do receptor de alta afinidade para IgE (FceRI), que são expressos na superfície de mastócitos e basófilos, tornando-os células alvo nesta doença. OBJETIVOS: Avaliar em pacientes com UCI, submetidos ao teste intradérmico de soro autólogo (ASST), o perfil de ativação dos basófilos, pela intensidade de expressão de marcadores de ativação/desgranulação e pela capacidade dos basófilos em responder aos estímulo com a IL-3 e anticorpo anti-IgE. Além disto, a presença de fator liberador de histamina foi avaliado nos soros dos pacientes. METODOLOGIA: Pacientes com UCI (n= 37) foram selecionados no Ambulatório de Urticária do Departamento de Dermatologia do Hospital das Clínicas da Faculdade de Medicina da USP e submetidos ao ASST. O grupo controle foi constituído por indivíduos saudáveis (n=38). A análise da expressão de FceRI, CD63, CD123 e CD203c em basófilos de sangue periférico foi realizada por citometria de fluxo. No ensaio in vitro de estimulação dos basófilos com anti-IgE, as células foram previamente incubadas com IL-3. O ensaio de liberação de histamina mediada por soros de pacientes com UCI foi realizado com três diferentes doadores de leucócitos e a histamina liberada dosada por ELISA de competição. RESULTADOS: Há um baixo número de basófilos no sangue periférico nos pacientes com UCI, coincidente com o baixo nível sérico de histamina. Os escassos basófilos no sangue periférico mostram elevada expressão de FceRI e uma regulação positiva da expressão de CD203c e CD63, independentemente do ASST. A análise funcional dos basófilos, mostra que somente a incubação com IL-3 recombinante já induz aumento significante da expressão de CD203c e da liberação de histamina dos basófilos de pacientes com UCI, que são intensificados com o estímulo por anticorpos anti-IgE após 15 e 40 minutos em relação ao grupo controle. Já a expressão de CD63 em basófilos após estímulo com anti-IgE, aumentou somente nos basófilos de indivíduos sadios, uma vez que os níveis de expressão basal estavam previamente aumentados. A presença de autoanticorpos liberadores de histamina foi analisada nos soros de pacientes com UCI. Três experimentos independentes foram realizados, evidenciando a ocorrência de 17% de positividade. CONCLUSÕES: Os resultados mostram que na UCI, os basófilos são sensibilizados in vivo, por fatores além dos autoanticorpos anti-FceRI e que funcionalmente, estão hiper-reativos a estímulos imunológicos. A presença de fatores séricos liberadores de histamina, independente do ASST, enfatiza que o teste intradérmico é sugestivo de autorreatividade e não de autoimunidade na UC / INTRODUCTION: Chronic Urticaria is characterized by recurrent, transitory, pruritic and erythematous wheals present for at least six weeks. In most patients the cause is unknown, defined as idiopathic (CIU), however, a sub-group has autoantibodies against the alfa chain of the high affinity IgE receptor (FceRIa) expressed on mast cells and basophils surface making it the target cells in this disease. OBJECTIVES: To evaluate in CIU patients, undergone autologous serum skin test (ASST), the activation profile of the basophils assessed by the expression of activation/degranulation markers and by the ability to release histamine in response to IL-3 priming and cross-linking with anti-IgE antibodies. Furthermore, the presence of histamine releasing factor in sera of patients was evaluated. METHODS: CIU patients (n = 37) were selected from the Dermatological Outpatient Clinic of the Hospital das Clínicas de São Paulo (HC-FMUSP) and submitted to the ASST. The control group consisted of healthy subjects (n=38). The analysis of the expression of FceRI, CD63, CD123 and CD203c on basophils from peripheral blood was assessed by flow cytometry. For the in vitro stimulation with anti-IgE antibodies, the cells were previously primed with human recombinant IL-3. The histamine release assay mediated by sera from patients with CIU was performed with three different donors of leukocytes and released histamine measured by competition ELISA. RESULTS: There is a low number of basophils in peripheral blood of patients with CIU, reflecting a low serum levels of histamine. The scarce basophils in peripheral blood show high expression of FceRI and an up-regulation of CD203c and CD63 marker expression, independently of the ASST. The functional analysis of basophils, revealed that recombinant IL-3 per se induces a significant increase in CD203c expression and the histamine release from basophils of patients with CIU, which are enhanced followed for 15 and 40 minutes of anti-IgE estimulation. The expression of CD63 in basophils upon anti-IgE stimulation, increased only in basophils of healthy individuals, since the baseline levels of CD63 expression on basophils of patients was already up-regulated. The presence of histamine release factors was examined in sera from CIU patients. Three independent experiments were performed, showing the occurrence of 17% of positivity. CONCLUSION: The results show that in CIU, the basophils are primed in vivo due to factor other than autoantibodies anti-FceRI and they have an hyperactive status to the immunological stimuli. The presence of serum histamine releasing factors, independent of the ASST, emphasizes that the intradermal test is suggestive of autorreactivity and not for autoimmunity in UC
853

Dinâmica de proteínas: efeitos da hidratação em estrato córneo e de detergentes em albumina / Protein dynamics: effects of hydration in stratum corneum and detergents in albumin

Silva, Junaine Vasques da 19 December 2002 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-07-25T13:32:13Z No. of bitstreams: 2 Dissertação - Junaine Vasques da Silva - 2002.pdf: 3727327 bytes, checksum: 4cb8c1db4d3fb95798779f39aae78673 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-07-26T12:05:00Z (GMT) No. of bitstreams: 2 Dissertação - Junaine Vasques da Silva - 2002.pdf: 3727327 bytes, checksum: 4cb8c1db4d3fb95798779f39aae78673 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-07-26T12:05:00Z (GMT). No. of bitstreams: 2 Dissertação - Junaine Vasques da Silva - 2002.pdf: 3727327 bytes, checksum: 4cb8c1db4d3fb95798779f39aae78673 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2002-12-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The main function of the most superficial layer of the epidermis, the Stratum Corneum (SC), is to provide a physical barrier that controls the transepidermal water loss as well as the permeation of another substances in both directions across the skin. The SC is formed by anabolically dead cells, the terminally differentiated corneocyte, and its function is essentially accomplished by forming a highly insoluble protein structure on the surface of the corneocytes, termed the cornified cell envelope, and by impeding water diffusion across the SC by mortaring the corneocytes together by layers of skin-specific lipids, essentially ceramide, cholesterol and fatty acid. In this work the cell envelope of the SC was spin labeled with a sulfhydryl-specific nitroxide reagent to investigate the water content effects upon the protein dynamics directly in the intact tissue. A two-state model for the nitroxide side chain described the coexistence of two spectral components in the electron paramagnetic resonance (EPR) spectra. The so-called strongly immobilized component, S, is associated with the EPR signal of a motionally restricted nitroxide fraction having its N-O group hydrogen bonded to protein (rigid structure) while the weakly immobilized component, W, corresponds to the signal provided by the spin labels with higher mobility (~10 times greater) exposed to the aqueous environment. The relative populations between these two mobility states, S and W, are in thermodynamic equilibrium. The standard Gibbs free energy, enthalpy and entropy changes for transferring the nitroxide side chain from the state contacting the solvent, W, to the one contacting protein, S, indicated that the reduction of the SC water content to below ~h 0.69, g H2O per g dry SC, stabilizes the protein interacting state, S. Upon decreasing the SC hydration level below ~h 0.69 the segmental motion of the polypeptide chains and the rotational motion of the spin-labeled side chain were also constrained. To test our methodology in a pure and very well known protein, we also studied the effects of two types of detergents on the bovine serum albumin (BSA). Both detergents, the anionic sodium dodecyl sulfate (SDS) and the zwitterionic N-hexadecyl-N,N-dimethyl-3-ammonium-1-propanesulfonate (HPS) increase the mobility of the protein backbone and of the nitroxide side chain. The thermodynamic parameters indicated that these detergents destabilize the protein favoring less compact conformations. This work can also be useful to improve the spectral analysis of site-directed spin labeling, especially for a more quantitative description in terms of thermodynamic parameters. / A camada mais superficial da epiderme, o Estrato Córneo (EC), tem como função principal a formação de uma barreira física que controla a perda de água do corpo bem como a permeação de outras substâncias em ambas as direções da pele. O EC é formado por células anabolicamente mortas, os corneócitos, os quais sofreram diferenciação celular terminal, e sua função é realizada formando uma estrutura de proteínas altamente insolúveis na superfície do corneócito, chamada de envelope celular, e também uma matriz lipídica, essencialmente ceramídios, colesterol e ácidos graxos, que dificultam a difusão da água. Neste trabalho, o EC foi marcado com marcadores de spin específicos para reagir com os grupos sulfidrilas das proteínas, para investigar os efeitos do conteúdo de água na dinâmica de proteínas diretamente no tecido intacto. Um modelo de dois estados para a cadeia lateral do nitróxido descreveu a coexistência de duas componentes espectrais de ressonância paramagnética eletrônica (RPE). A componente denominada fortemente imobilizada (S), surge de uma fração de marcadores com o átomo de oxigênio do nitróxido ligado à proteína (estrutura rígida) enquanto a componente fracamente imobilizada é gerada pelos marcadores com mobilidade mais alta (~10 vezes maior) e expostos ao ambiente aquoso. As populações relativas entre estes dois estados de mobilidade, S e W, estão em equilíbrio termodinâmico. Os parâmetros da termodinâmica: energia livre padrão de Gibbs, entalpia e entropia, envolvidos na transferência da cadeia lateral do nitróxido do estado W, contatando ao solvente, para o estado S, contatando a proteína, indicaram que a redução do conteúdo de água para abaixo de ~0.69g de H2O por g de EC seco, estabiliza o estado S (cadeia lateral do nitróxido dobrada sobre a cadeia principal da proteína). Ao diminuir o nível de hidratação para abaixo de ~ h 0.69 (g H2o/g EC seco) o movimento local da cadeia polipeptídica e o movimento rotacional da cadeia lateral do marcador de spin foram ambos reduzidos. Para testar nossa metodologia em uma proteína pura e bem conhecida, estudamos os efeitos de dois tipos de detergentes sobre a albumina do soro bovino (BSA). Ambos os detergentes, o aniônico dodecil sulfato de sódio (SDS) e o ziteriônico N-hexadecil-N,N-dimetil-3-amônio-1-propanosulfonato (HPS) aumentaram a mobilidade da cadeia principal da proteína e da cadeia lateral do nitróxido. Os parâmetros termodinâmicos indicaram que estes detergentes desestabilizam a proteína favorecendo conformações menos compactas. Os resultados do presente trabalho também podem contribuir para aprimorar a
854

Estudo espectroscópico da interação entre as proteínas séricas humanas Albumina e transferrina com o potencial agente quimioterapêutico cloreto de cis-tetraminodiclorutênio (III) / Spectroscopic study of the interaction between human serum proteins albumin and transferrin with the potential chemotherapeutic agent cis-tetraminodiclororutênio chloride (III)

Guedes, Adriana Pereira Mundim 13 September 2013 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-10-13T21:33:03Z No. of bitstreams: 2 Dissertação - Adriana Pereira Mundim Guedes - 2013.pdf: 2999561 bytes, checksum: 755cb864a8446e6ff5c334be00ea5367 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-10-16T18:47:44Z (GMT) No. of bitstreams: 2 Dissertação - Adriana Pereira Mundim Guedes - 2013.pdf: 2999561 bytes, checksum: 755cb864a8446e6ff5c334be00ea5367 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-16T18:47:44Z (GMT). No. of bitstreams: 2 Dissertação - Adriana Pereira Mundim Guedes - 2013.pdf: 2999561 bytes, checksum: 755cb864a8446e6ff5c334be00ea5367 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-09-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Motivated by the perspective of ruthenium complexes to be used in cancer treatment, our research group has tested the hipotesis that some complexes of Ru (III) are able to interact with serum proteins, particularly albumin and transferrin. The Complex cis- [RuCl2(NH3)4]Cl (CTRu(III)) have been tested against different kind of tumor cells, obtaining good results. Starting from promising results obtained with this compound, subsequent studies are required to understanding the mechanism by which it exerts specificity for tumor cells. In this article, we report the first application of absorption UV-Vis, Fluorescence and Electron Paramagnetic Resonance (EPR) spectroscopy, to study the complex CTRu(III) interaction with human serum albumin (hsA) and bovine serum albumin (bsA). Fluorescence measurements revealed strong proteinsbound complex with Ksv of 1.32 x 105 and 3.71 x 105 for hsA and bsA, respectively. EPR spectra from mono-nuclear Ru(III) complexes in buffer, showed a significant decrease in the overall signal intensity following the first aquation step, is consistent with the formation of oxo-bridged Ru(III) dimers. EPR spectra revealed that the BSA very rapid binding to the protein via covalent binding through ligand-exchange with protein side chains, likely with histidine imidazoles. On the other hand, the complex binds non-covalently in hsA, probably as a product of the oligomerization of the complex in hemin-biding pocket. Furthermore, two species are slowly formed by covalent binding of the complex with the histidine residues, producing a species of axial symmetry and the other rhombic symmetry. These bonds seem to arise from the interaction of the complex with the histidine residue located in the binding Sudlow’s site II. / Motivado pela perspectiva de complexos de rutênio podem ser utilizados no tratamento do câncer, o nosso grupo de pesquisa testou a Hipótese que alguns complexos de Ru (III) são capazes de interagir com as proteínas do soro, particularmente albumina e transferrina. O complexo de cis-[RuCl2(NH3)4]Cl (CTRu(III)) foi testado contra diferentes tipos de células tumorais, obtendo bons resultados. A partir de resultados promissores obtidos com este composto, estudos subsequentes são necessários para a compreensão do mecanismo pelo qual ele exerce sua especificidade para células de tumor. Neste artigo, apresentamos a aplicação de espectroscopia de absorção UV-vis, fluorescência e ressonância paramagnética eletrônica (RPE), para estudar a interação do complexo CTRu(III) com albumina sérica humano (hsA) e a albumina sérica bovina (bsA). Medidas de fluorescência revelaram uma forte ligação do complexo com as proteínas com Ksv de 1,32 x 105 e 3,71 x 105 para hsA e bsA, respectivamente. Espectros de RPE de complexos de Ru (III) mono-nucleares em tampão mostraram um decréscimo significativo na intensidade do sinal global após a primeira passo de aquação, que é consistente com a formação de dímeros de oxo complexos de Ru (III). Os espectros de RPE revelaram que a ligação à bsA é muito rápida, a ligação covalente à proteína ocorre através de troca dos ligantes com cadeias laterais de proteínas, provavelmente com o imidazol da histidina. Por outro lado, o complexo se liga não covalentemente na hsA, provalente como produto da oligomerização do complexo no bolso de ligação hemin. Além disso, duas espécies são formadas lentamente por ligação covalente do complexo com os resíduos histidina, produzindo uma espécie de simetria axial e a outra de simetria rômbica. Essas ligações parecem surgir pela interação do complexo com o resíduo histidina localizado no sítio de ligação Sudlow II.
855

Estudo epidemiológico de Leishmaniose Tegumentar Americana (LTA) no município de Itambaracá, região norte do Estado do Paraná, Brasil, em áreas de influência do complexo hidrelétrico na bacia do rio Paranapanema, 2004-2006 / Epidemiological study of American Cutaneous Leishmaniasis (ACL), in northern Paraná State, Brazil, in areas around the hydroelectric plants on the Paranapanema river, 2004 -2006.

Mariza Fordelone Rosa Cruz 29 February 2008 (has links)
Resumo. Foi realizado um estudo epidemiológico para avaliação dos fatores determinantes para a transmissão da LTA. O estudo foi realizado na área urbana, periurbana e rural da cidade de Itambaracá, incluindo a Vila Rural e as localidades de Porto Almeida e São Joaquim do Pontal, as duas últimas próximas à área impactada pelas hidrelétricas de Canoas I e II, no rio Paranapanema. Capturou-se de fevereiro de 2004 a junho 2006, 3.187 flebotomíneos. As espécies predominantes foram Nyssomyia neivai (34,36%), Pintomyia pessoai (32,57%), Migonemya migonei (11,61%), Nyssomyia whitmani (8,82%) e Pintomyia fischeri (2,73%) todas elas com capacidade de transmissão da doença. Para Ny neivai, houve predominância de machos e para as outras espécies vetoras, as fêmeas prevaleceram, com diferença estatística significante (p<0,001). As espécies mais abundantes, segundo o índice de abundância das espécies padronizado, foram Ny neivai, Pi. pessoai, Ny whitmani, Br. brumpti, Mg migonei e Pi fischeri. As maiores freqüências e diversidade das espécies foram encontradas na localidade de Porto Almeida (PA), seguida por São Joaquim do Pontal (SJP). Ny neivai apresentou médias sazonais mais elevadas e na distribuição mensal, picos em fevereiro, maio e outubro. A maior média horária desta espécie foi registrada das 19:00 às 20:00 h (1,2) mas mostrou-se ativa das 23:00 às 10:00 h da manhã. A prevalência de Acs da classe IgG para LTA em RIFI, na população humana foi de 6,73%, nos caninos de 1,75% e nos equídeos de 16,0 %. Em EIE/ELISA, a prevalência para os caninos foi de 16,49%. Na PCR, todos os cremes leucocitários correspondentes à soros reagentes a Acs da classe IgG (humanos), e Ac totais (eqüinos e caninos) foram negativos para Leishmania sp. No inquérito sócio econômico, verificou-se que a população entrevistada em sua maioria pertence à etnia branca e à faixa etária de 30-50 anos, recebem em torno de dois salários mínimos, possuem ocupações voltadas à agricultura e pecuária, nível de escolaridade fundamental (1º grau), habita casas de alvenaria, possuem animais domésticos com seus abrigos próximos às casas. Realizam atividades de trabalho e lazer em áreas de risco em proximidades às matas, áreas com animais silvestres e domésticos e com presença de matéria orgânica, que são fatores atrativos aos flebotomíneos. A população entrevistada, de uma forma geral, desconhece os aspectos da transmissão da LTA. Observou-se em todas as localidades amostradas a presença de flebotomíneos, com predominância de cinco espécies com capacidade vetorial de agentes da LTA, destacando-se Ny. Neivai , incluindo os peridomicílios. Houve transmissão ativa da doença, ocorrendo dois casos notificados e autóctones, em área de baixa freqüência de espécimes. A soroprevalência na população humana (6,73%) foi considerável, embora seja uma área de baixa ocorrência da doença. Nas localidades onde havia um foco mais recente da doença, em SJP, os cães e eqüinos apresentaram sorologia positiva. A alta prevalência de reagentes na sorologia observada em eqüídeos sugere que estes animais poderiam ser usados como sentinela para a detecção precoce da circulação do agente da LTA nas áreas estudadas. / Abstract. An epidemiological study was carried out in the urban area of Itambaracá and rural areas of the same municipality, including Vila Rural, Porto Almeida and São Joaquim do Pontal, to investigate the phlebotomine fauna and behavioral aspects of its species and also some determining factors of the transmission of American cutaneous leishmaniasis (ACL). The last two localities mentioned are situated close to the areas impacted by the Canoas I and II hydroelectric plants on the Paranapanema river. A total of 3,187 phlebotomines were captured between February 2004 and June 2006. Nyssomyia neivai predominated (34.36%), followed by Pintomyia pessoai (32.6%), Migonemyia migonei (11.6%), Nyssomyia whitmani (8.8%) and Pintomyia fischeri (2.7%), all of them implicated in the transmission of the disease. Regarding Ny. neivai, males predominated over females which may indicate the proximity of its breeding places to the capture sites. As for all the other vector species, the females were predominant, with significant statistical differences (p < 0,001). Ny neivai, Pi. pessoai, Ny. whitmani, Br. brumpti, Mg. migonei and Pi. fischeri presented the highest values for the species standardized abundance index. The greatest frequencies and diversity of the species were found at Porto Almeida (PA), a locality situated close to a well preserved forest fragment and secondly at São Joaquim do Pontal (SJP), with degraded forest. Of all the species, Ny. neivai presented the highest monthly averages with the main peak occurring in successive months of April. Its greatest hourly average was registered at 19:00-20:00 hours, but the species presented activity from 23:00 p.m. to 10:00 a.m. The prevalence of Ac IgG class, serum-reagents for Leishmania obtained with RIFI from the human, canine and equine populations was 6.73% (20/297), 1.75% (5/285) and 16% (8/50), respectively. A prevalence of 16.4% was observed by the EIE/ELISA test only for the canine population. The buffy-coat of all the reagent human and animal blood samples was tested by the polymerase chain reaction (PCR) to investigate the presence of Leishmania, with negative results. In the socioeconomic survey, it was found that the majority of the people interviewed belonged to the white ethnic and 30-50 year-old groups, earning two minimum salaries, exercising occupations associated with agriculture and livestock breeding, of fundamental school level, inhabiting brick houses and keeping pets and domestic animals in and around them. They exercise their work and leisure activities in risk areas close to forest fragments, thus in areas containing both wild and domestic animals with the presence of organic matter, which attract the sandflies. The population interviewed was, in general, ignorant of the facts involved in ACL transmission. Sandflies were observed at all the sites sampled, with the predominance of five vectors of the ACL agents, with Ny. neivai, the main vector in all three areas, also being captured in the peridomiciles. Active transmission of the disease, with two cases registered, was observed at sites with very low frequency of this sandfly. The serum prevalence in the human population (6.73%) was considerable, despite this being an area of few registered ACL cases. In the localities in which there was a more recent focus of the disease, in SJP, the dogs and equines presented positive serology. The high prevalence of equine serum reagents suggests that these animals could be used as sentinels for the early detection of the presence of the ACL agent in the area studied.
856

Cultivo de célula BHK-21 C13 em meio de cultura livre de soro fetal bovino adaptada para crescimento em suspensão / Cell bhk-21 c13 culture in the means of free culture of fetal bovine serum adapted for suspension growth

Jaci Leme 14 December 2016 (has links)
Células de mamíferos são os hospedeiros mais frequentemente utilizados para a fabricação de proteínas biofarmacêuticas e para a produção de vacinas virais, A qualidade é um elemento-chave para o estabelecimento de um processo de bioconversão eficiente. No presente trabalho utilizamos a linhagem de células BHK- 21C13(Baby Hamster Kidney) adaptadas para cultivo em suspensão. O uso de Soro Fetal Bovino (SFB) é tradicionalmente utilizado, sendo considerado um suplemento universal, pois permite o crescimento em várias linhagens de células de mamíferos; porém, uso de SFB apresenta risco de infecção por prions, variabilidade entre lotes e aumento no custo em etapa de purificação (Downstream processing). O objetivo do presente trabalho foi comparar o cultivo de células BHK-21 C13 entre dois meios suplementados com SFB e sem SFB, através do estudo cinético para cultivo em suspensão estático e agitado com frascoT, frasco spinner e biorreator, respectivamente. Os parâmetros; Xmáx e &#181;máx, não foram significativamente influenciados pelo meio de cultura em cultivo estático, em cultivo com agitação em frasco spinner e também no cultivo em biorreator. O tempo de duplicação ficou próximo para todas as condições testadas. A produtividade alcançada foi: 0,032x106 cel/mL.h-1 para o meio com SFB e 0,031 X106 cel/mL.h-1 para o meio sem SFB. Ao final do processo foi possível obter uma concentração celular em torno de 4,7x106 cel/mL, tanto para o cultivo com SFB quanto para o cultivo sem SFB. Dessa forma, o uso de meio de cultivo sem SFB não alterou os principais parâmetros cinéticos, não apresentando as desvantagens do uso do SFB. / Mammalian cells are the most frequently used hosts for the production of biopharmaceutical proteins and viral vaccines. Quality is a key element for the establishment of an efficient bioconversion process. In this work, we used the cell line Baby Hamster Kidney C13 (BHK-21 C13) adapted to suspension culture was used. Fetal Bovine Serum (FBS) is traditionally used and it is considered a universal insert due to its power to increase cell growth in this kind of animal cells. However, the utilization of FBS introduces risks of infection from prions, variability between batches and increase in cost associated to purification stages (downstream processing). This work aimed to compare the kinetic behaviors of BHK-21 C13 cells in two media supplemented with FBS and without FBS using both one static and two suspension systems, T-flask, spinner flask and bioreactor respectively. The parameters; Xmax and &#181;max were not significantly influenced by the culture medium in T- flask culture static, in spinner flask cultivation and were neither significantly influenced by growing in culture media stirred bioreactor. The doubling time was close to all conditions tested. At the end of the growth phase it was possible to obtain a nearby cell concentration of 4.7 x 106 cells / ml, both for cultivation with FBS as for FBS without cultivation. Thus, the use of culture medium without FBS did not affect the main kinetic parameters. Besides, it does not show the disadvantages of culture media using FBS.
857

[en] DEVELOPMENT AND COMPARATIVE STUDY OF SPECTROFLUORIMETRIC AND VOLTAMMETRIC METHODOLOGIES FOR THE DETERMINATION OF THALIDOMIDE IN ONE COMMERCIAL FORMULATION, URINE AND BLOOD SERUM / [pt] DESENVOLVIMENTO E ESTUDO COMPARATIVO DE METODOLOGIAS ESPECTROFLUORIMÉTRICA E VOLTAMÉTRICA PARA A DETERMINAÇÃO DE TALIDOMIDA EM UM FÁRMACO, URINA E SORO SANGÜÍNEO

CARLOS EDUARDO CARDOSO 21 July 2003 (has links)
[pt] No presente trabalho foram desenvolvidas duas metodologias analíticas para a determinação de talidomida, um composto de reconhecida importância farmacológica. As metodologias espectrofluorimétrica e voltamétrica desenvolvidas foram comparadas em termos de desempenho analítico.As características fluorescentes e eletroquímicas da talidomida foram estudadas para que se encontrassem condições experimentais que fornecessem máximo sinal fluorescente do analito em solução na temperatura ambiente e possibilidade de pré-concentração do analito no eletrodo de mercúrio.Nas condições experimentais otimizadas para a talidomida, limites de detecção compreendidos entre 10-6 e 10-9 g L-1 foram obtidos para o método espectrofluorimétrico e voltamétrico, respectivamente. Faixas lineares dinâmicas entre 2 e 4 ordens de grandeza foram alcançadas dependendo do método e do interferente presente na amostra. Esses parâmetros de mérito se mostraram adequados para o problema proposto. O possível efeito interferente de substâncias geralmente usadas em associação com o analito foi estudado, e estratégias para minimização das interferências foram desenvolvidas. Enquanto a tetraciclina não interferiu no método espectrofluorimétrico, o uso combinado de meio ácido e irradiação UV da amostra foi necessária para permitir a quantificação do analito em presença de sulfanilamida. Na voltametria, as interferências da tetraciclina e da sulfanilamida puderam ser compensadas pelo uso da quantificação pelo método de adição do analito. Nas determinações dos fluídos biológicos, o uso da extração em coluna de sílica C18 mostrou-se bastante eficiente na separação do analito dos interferentes da matriz para o método espectrofluorimétrico e para o voltamétrico, no caso do soro sangüíneo. Para a urina, apenas a clarificação da amostra com sulfato de amônio foi suficiente no caso da determinação voltamétrica.Os métodos desenvolvidos foram testados na dosagem de talidomida presente em uma formulação comercial e em amostras de urina e soro sangüíneo enriquecidas com o analito. Para tal, utilizaram-se os procedimentos de curva de calibração (espectrofluorimetria) e método da adição do analito (voltametria). Em todos os casos, as recuperações obtidas estiveram compreendidas na faixa de 96,5 a 107,6 %, dentro da faixa de recuperação estabelecida pela Farmacopéia dos Estados Unidos da América. / [en] In the present work two analytical methodologies were developed aiming the determination of thalidomide, an important pharmacological compound. The developed spectrofluorimetric and the voltammetric based analytical methodologies were compared in terms of analytical performance. The thalidomide fluorescent and the electrochemical characteristics were studied in order to find experimental conditions for maximum fluorescence in solution and at room temperature and to allow analyte pre- concentration on the mercury electrode. Using the optimized experimental conditions, limits of detection between 10-6 to 10-9 g L-1 were achieved respectively for the spectrofluorimetric method and for the voltammetric method. Dynamic linear ranges between 2 and 4 orders of magnitude were obtained depending on the method utilized and the interferent substances present in the sample. Those parameters of merit were suitable for this proposed analytical problem. The potential interference effect from substances usually used in association with thalidomide, were studied and strategies for the minimization of such interferences were developed. While no interference in the spectrofluorimetric method was observed for tetracycline, the combined use of acidic medium and UV irradiation of the samples was necessary to allow the analyte determination in the presence of sulfanilamide. For the voltammetric method, interferences from tetracycline and sulfanilamide could be compensated by quantifying thalidomide using the analyte addition method. For the determination in biological fluids, the use a solid-liquid extraction on a C18 column was found to be very effective for the analyte separation and elimination of matrix interferences for the spectrofluorimetric method and for the voltammetric method developed for blood serum. For urine samples, a clean-up step using ammonium sulfate was found to be sufficient for the voltammetric determination of thalidomide. The developed methodologies were tested by determining the thalidomide content in a commercial pharmaceutical formulation and in analyte spiked biological fluids using calibration curves (spectrofluorimetric) and analyte addition method (voltammetric). In all cases, the recoveries were between the 96,5 and 107,6 %, within the recovery range considered adequate according to the United States Pharmacopoeia.
858

Associação entre carga ácida da dieta e bicarbonato sérico em portadores de doença renal crônica / Association between dietary acid load and serum bicarbonate in patients with chronic kidney disease

Angeloco, Larissa Rodrigues Neto 15 December 2017 (has links)
A acidose metabólica é um achado comum em pacientes portadores de Doença Renal Crônica (DRC). Acredita-se que a dieta pode afetar o equilíbrio ácidobase do corpo por meio do fornecimento de precursores ácidos ou de base. No entanto, os resultados inconclusivos apontados na literatura indicam que ainda são necessários estudos bem delineados para comprovar a existência dessa associação. O principal objetivo desse estudo foi determinar o potencial de carga ácida renal (PRAL) proveniente da dieta e avaliar a sua associação com o bicarbonato sérico (HCO3) em pacientes com DRC enquanto em suas dietas habituais. Associações do HCO3 com o gasto energético de repouso (GER) e com oxidações proteicas e lipícas também foram estudadas. Trata-se de um estudo transversal realizado com 100 pacientes distribuídos igualmente nos estágios 3 e 4 da DRC entre 20 e 69 anos. Avaliação do estado nutricional foi feita por meio da antropometria, registro alimentar e exames bioquímicos, o qual incluiu os produtos proteicos de oxidação avançada e os isoprostanos. O HCO3 foi determinado por meio da gasometria venosa. GER foi medido pela calorimetria indireta. O PRAL foi determinado por meio do registro alimentar usando um algoritmo que inclui dados dietéticos da ingestão de proteína, fósforo, magnésio, cálcio e potássio descritos por Remer e Manz (1995). Também foi feita a diferenciação no consumo de proteína animal e vegetal. A análise dos resultados foi feita em quartis de HCO3 para as variáveis GER e parâmetros de oxidação, o restante das análises foram feitas por quartis de PRAL. Para comparação das variações médias dos quartis foi utilizado o teste one-way ANOVA. A associação entre a estimativa do PRAL e o HCO3 foi avaliada por modelos de regressão linear ajustados. A maior parte dos nossos pacientes portadores de DRC encontravam-se com excesso de peso associado a um aumento da circunferência abdominal e da porcentagem de gordura corporal. A mediana do PRAL foi de 6,8 mEq/dia com uma variação entre -24 a 52 mEq/dia. O PRAL mais elevado foi associado com o HCO3 mais baixo de uma forma graduada (p < 0.02). Encontramos uma diferença de 2,07 mmol/L no HCO3 entre o primeiro e o último quartil, sendo o valor do último quartil de PRAL menor em relação ao primeiro. A proteína animal apresentou uma correlação inversa com o bicarbonato sérico. O GER e os marcadores de oxidação lipíca e proteica não apresentaram associações com os níveis de HCO3. Esses resultados reforçam a possibilidade de que dietas com alto teor de carga ácida podem desempenhar um papel relevante no equilíbrio ácidobase em pacientes portadores de DRC, além de consolidar o uso da carga ácida da dieta como uma abordagem diferencial e complementar às outras estratégias no tratamento dietético da DRC. / Metabolic acidosis is a common complication in patients with chronic kidney disease (CKD). Acid-inducing diets are believed to impact on acid-base balance. However, well-designed studies are still needed to prove the association between dietary acid load and serum bicarbonate. The main aim of this study was to calculate the potential renal acid load (PRAL) of selected, frequently consumed foods and to evaluate its association with serum bicarbonate (HCO3) in patients with CKD. Associations of HCO3 with resting energy expenditure (REE) and with protein and lipid oxidation were also studied. It is a cross-sectional study with 100 patients equally distributed in stages 3 and 4 of CKD between 20 and 69 years. Nutritional status was assessed by anthropometric measurements, 3-day food recall, biochemical analysis including advanced oxidation protein products and isoprostanes. Venous blood gases was used to measure HCO3. GER was measured by indirect calorimetry. PRAL was determined by food record using an algorithm that includes protein, phosphorus, magnesium, calcium and potassium intake described by Remer and Manz (1995). Dietary intake of animal and vegetable protein were also evaluate. For analysis, we used quartiles of HCO3 for GER and oxidation parameters and for the others variables we used quartilhes of PRAL. ANOVA one-way test was used to compare the mean of the quartiles. The association between PRAL and HCO3 was assessed by linear regression models. Most of the patients were overweight with increased waist circumference and body fat. The median PRAL was 6.8 mEq/day with a variation between -24 to 52 mEq/day. Higher PRAL was associated with lower serum bicarbonate in a graded fashion (P trend 0.02). Serum bicarbonate was 2.07 mEq/L lower among those in the highest compared with the lowest quartile of PRAL. Animal protein was inversely correlated with serum bicarbonate. REE and lipid and protein oxidation markers showed no association with HCO3 levels. These results reinforce the possibility that diets with high dietary acid load may play a relevant role in the acid-base balance in CKD patients. In addition to consolidating the use of PRAL as a differential and complementary approach to other strategies in the nutritional treatment of CKD.
859

Développement et caractérisation d'outils immunologiques dirigés contre des récepteurs membranaires d'intérêt thérapeutique / Development and characterization of immunological tools directed against membrane proteins of therapeutic interest

Hartmann, Lucie 16 May 2019 (has links)
Les Récepteurs Couplés aux Protéines G (RCPG) constituent la plus grande famille de protéines membranaires chez l’Homme, et leur implication dans un grand nombre de processus physiologiques justifie pleinement l’intérêt de leur étude. Les anticorps spécifiques de ces récepteurs sont des outils polyvalents à haute valeur ajoutée, qui restent toutefois encore trop rarement disponibles, notamment en raison des difficultés techniques posées par leur génération. Ce manuscrit présente la mise au point d’une méthode d’immunisation alternative et innovante, mettant en jeu des particules virales recombinantes dérivées du Virus de la Forêt de Semliki (SFV) codant pour le récepteur d’intérêt. Appliquée au récepteur de l’adénosine A2A humain, l’immunisation permet d’engendrer la surexpression de celui-ci à la surface des cellules de l’animal infecté, et de provoquer l’apparition d’une réponse immunitaire. Cette approche permet d’une part de générer un sérum polyclonal de souris spécifique au récepteur, et ouvre donc une nouvelle voie pour l’obtention d’anticorps monoclonaux murins. Elle semble d’autre part prometteuse pour la génération de nanobodies. / G Protein Coupled Receptors (GPCRs) constitute the largest membrane protein family represented in the human genome. Their involvement in a wide number of biological processes fully supports their study. GPCR-targeting antibodies are versatile and valuable tools, which remain scarcely available, chiefly because their generation is a challenging process. This thesis presents an alternative and innovative strategy in which recombinant Semliki Forest Virus (SFV) particles coding for the receptor of interest are used as immunogens. When applied to the human version of the Adenosine A2A receptor, this method enables to cause the receptor’s overexpression at the surface of the infected animal cells, which generates an immune response. This strategy enables to raise receptor-specific mouse polyclonal serum. It opens a new path towards the generation of monoclonal mouse antibodies. Additionally, it seems to also be a promising approach to develop nanobodies.
860

Comparison of rice bran oil margarine with Flora margarine and Flora pro-activ margarine for lowering cholesterol : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Human Nutrition at Massey University, Turitea Campus, Palmerston North, New Zealand

Eady, Sarah Louise January 2008 (has links)
Phytosterols have been shown to be effective in reducing serum cholesterol levels in numerous human clinical studies and regular consumption is recommended as part of therapeutic lifestyle changes aimed at reducing low density lipoprotein (LDL-C) in the treatment of hyperlipidaemia, a risk factor for cardiovascular disease. Fat based spreads have been shown to be a very successful vehicle for delivery of plant sterols, readily accepted by consumers and efficacious in reducing cholesterol levels. Alfa One™ Rice Bran Oil (RBO) spread is a new product entering into the market place. It is derived from rice bran oil and contains high levels of unsaponifiable material rich in phytosterols, triterpene alcohols, ferulic acid esters ([gamma]-oryzanol) and vitamin E isomers. As such it may have the potential to lower serum cholesterol levels when consumed on a daily basis. In order to establish the effectiveness of Alfa One™ Rice Bran Oil (RBO) spread compared with Flora pro-activ® margarine, a well established brand of plant sterol margarine already proven to lower cholesterol, a randomised double blind cross-over human clinical trial over 12 weeks was conducted. The study was divided into two treatment arms. The first arm of the study was to determine whether Alfa One™ RBO spread (containing 1.5% plant sterols) could lower total and LDL cholesterol levels to a greater extent than standard Flora margarine (containing no plant sterols) or Flora Pro-activ® margarine (containing 8% plant sterols). The second study arm tested the proposition that daily consumption of Alfa One™ Rice Bran Oil (RBO) spread in conjunction with rice bran oil (containing 0.5% plant sterols) would lower total and LDL cholesterol to a greater extent than Alfa One™ RBO spread in isolation and more than Flora margarine in conjunction with sunflower oil. Eighty mildly hypercholesterolaemic individuals (total cholesterol [greater than or equal to] 5 mmol/L and [less than or equal to] 7.5 mmol/L) were recruited and randomised into two groups of forty. Participants were asked to continue with their normal dietary pattern but to replace any margarine/butter/fat consumption with the trial products. One group of 40 were then assigned to the first treatment arm of the study (margarine-only group) and were randomised to consume 20 g (4 teaspoons) Alfa One™ RBO spread daily for 4 weeks, or 20 g Flora margarine daily for 4 weeks, or 20 Flora pro-activ® daily for 4 weeks. Phytosterol levels delivered in these amounts were: RBO margarine: 118mg phytosterol and 14 mg [gamma]-oryzanol; Flora proactiv® 1600 mg phytosterol; Flora margarine 0mg phytosterol. The second group of 40 were allocated to the second arm of the trial (margarine and oil group) and consumed 20 g Alfa One™ RBO spread and 30 ml rice bran oil (RBO) daily for 4 weeks, or 20 g Flora margarine and 30 ml sunflower oil daily for 4 weeks, or 20 g Alfa One™ RBO spread daily for 4 weeks, changing treatment at the end of each 4-week period. Phytosterol amounts delivered in these amounts were: RBO margarine: 118 mg phytosterol and 14 mg [gamma] oryzanol; RBO 222mg mg phytosterol, 150 mg [gamma] oryzanol. Each participant consumed all three treatments in a random order over a 12 week period. At baseline and following each 4 week intervention period, measurements were made of weight and blood pressure. Venous blood samples were collected for analysis of total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), total cholesterol: HDL-C, triglycerides and plasma phytosterols. Three-day diet records from each individual were also collected for analysis of normal dietary intake. Results showed that compared to a standard Flora margarine, Alfa One™ RBO spread significantly reduced total cholesterol by 2.2% (P=0.045), total cholesterol:HDL by 4.1% (P=0.005) and LDL-C by 3.5% (P=0.016), but was not as effective overall as Flora Pro-activ® which reduced total cholesterol by 4.4% (P=0.001), total cholesterol:HDL by 3.4% (P=0.014) and LDL-C by 5.6% (P=0.001). Consumption of Flora margarine alone produced no significant decrease from baseline figures in any of the cholesterol parameters measured. Surprisingly, in group two, the addition of rice bran oil to the Alfa One™ RBO spread produced no differences in cholesterol levels. The reason for this unexpected result is being explored further. These results confirm that Alfa One™ RBO spread is effective in lowering serum cholesterol levels when consumed as part of a normal diet. Studies have shown that a 1% reduction in LDL-C can equate to a 2% decrease in coronary heart disease (CHD) risk thus suggesting that the 3.5% reduction demonstrated by Alfa One™ RBO spread in this study could be effective in reducing CHD risk as much as 6% in a mildly hypercholesterolaemic population.

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