Thesis (Ph.D.)--University of Alabama at Birmingham, 2007. / Title from PDF title page (viewed on Feb. 19, 2010). Includes bibliographical references.

Thesis (Ph.D. in Immunology) -- University of Colorado Denver, 2008. / Typescript. Includes bibliographical references (leaves 174-182). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;

abstract: ATP synthase is a large multimeric protein complex responsible for generating the energy molecule adenosine triphosphate (ATP) in most organisms. The catalysis involves the rotation of a ring of c-subunits, which is driven by the transmembrane electrochemical gradient. This dissertation reports how the eukaryotic c-subunit from spinach chloroplast ATP synthase has successfully been expressed in Escherichia coli and purified in mg quantities by incorporating a unique combination of methods. Expression was accomplished using a codon optimized gene for the c-subunit, and it was expressed as an attachment to the larger, more soluble, native maltose binding protein (MBP-c1). The fusion protein MBP-c1 was purified on an affinity column, and the c1 subunit was subsequently severed by protease cleavage in the presence of detergent. Final purification of the monomeric c1 subunit was accomplished using reversed phase column chromatography with ethanol as an eluent. Circular dichroism spectroscopy data showed clear evidence that the purified c-subunit is folded with the native alpha-helical secondary structure. Recent experiments appear to indicate that this monomeric recombinant c-subunit forms an oligomeric ring that is similar to its native tetradecameric form when reconstituted in liposomes. The F-type ATP synthase c-subunit stoichiometry is currently known to vary from 8 to 15 subunits among different organisms. This has a direct influence on the metabolic requirements of the corresponding organism because each c-subunit binds and transports one H+ across the membrane as the ring makes a complete rotation. The c-ring rotation drives rotation of the gamma-subunit, which in turn drives the synthesis of 3 ATP for every complete rotation. The availability of a recombinantly produced c-ring will lead to new experiments which can be designed to investigate the possible factors that determine the variable c-ring stoichiometry and structure. / Dissertation/Thesis / Ph.D. Biochemistry 2011

No description available.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / IntroduÃÃo: HipÃxia constitui em uma caracterÃstica comum de tumores sÃlidos, como em cÃnceres de cabeÃa e pescoÃo, e nessas condiÃÃes, uma via de sinalizaÃÃo envolvendo um regulador de resposta a oxigÃnio, chamado de Fator Induzido por HipÃxia-1 (HIF-1) tem-se destacado, na tentativa de permitir uma melhor compreensÃo sobre a biologia tumoral do cÃncer. Objetivo: Investigar o papel do HIF-1 em carcinoma epidermÃide oral (CEO) e em lesÃes potencialmente malignas que apresentam displasia epitelial oral (DEO). MÃtodos: Estudo observacional, analÃtico e transversal, atravÃs do diagnÃstico e anÃlise imuno-molecular de lesÃes malignas e potencialmente malignas. Foram incluÃdos 10 casos biopsiados com diagnÃstico histopatolÃgico de CEO e 10 casos de DEO. Utilizou-se a tÃcnica imunohistoquÃmica da Estreptoavitina-Biotina com o anticorpo HIF-1 (marca Abcam, diluiÃÃo 1:200, 60 minutos, recuperaÃÃo antigÃnica com citrato pH6 Pascal), analisando 05 campos de cada caso no aumento de 400X. O nÃmero de cÃlulas em cada um dos cinco campos foi somado e considerou-se como unidade amostral o percentual de cÃlulas imuno-positivas para HIF-1α conforme marcaÃÃo nuclear e citoplasmÃtica, bem como intensidade desta Ãltima. Os resultados foram obtidos e comparados entre grupos por meio dos testes t de Student e ANOVA multifatorial, seguido do pÃs-teste de Bonferroni, tomando como base os nÃveis de significÃncia de 5%. Resultados: Foi observado uma expressÃo citoplasmÃtica de HIF-1α em 58.4Â6.0% das cÃlulas epiteliais das DEO e em 77.8Â3.9% das cÃlulas dos CEO, com diferenÃa significante (p=0.022). O percentual de cÃlulas positivas para HIF-1α com marcaÃÃo nuclear tambÃm mostrou diferenÃa significante (p=0.021) entre DEO (0.2Â0.1%) e CEO (2.4Â0.8). NÃo houve diferenÃa significante entre o percentual de cÃlulas com imunomarcaÃÃo positiva fraca em citoplasma entre DEO e CEO (p=0.337), no entanto, houve aumento significante no percentual de cÃlulas com marcaÃÃo citoplasmÃtica moderada (p=0.029) e forte (p=0.031) entre DEO e CEO. ConclusÃo: Foi observada uma aumento da expressÃo, nuclear e citoplasmÃtica, de HIF-1α de DEO para CEO, sugerindo seu envolvimento em estÃgios iniciais da carcinogÃnese oral. RelevÃncia ClÃnica: Buscar o entendimento das complexas vias de sinalizaÃÃo, bem como do microambiente tumoral, e diferentes comportamentos biolÃgicos no cÃncer oral. / Introduction: Hypoxia is a common feature in solid tumors, such as head and neck cancers, and in these conditions a signaling pathway involving a response regulator oxygen, called hypoxia-inducible factor-1 (HIF-1) we have highlighted in an attempt to provide a better understanding of tumor biology of cancer. Objective: To investigate the role of HIF-1 in oral squamous cell carcinoma and premalignant lesions presenting oral epithelial dysplasia. Methods: Observational, analytical and cross through the diagnosis and immuno-molecular analysis of malignant and premalignant lesions. 10 biopsied cases with histopathological diagnosis of the CEO and DEO 10 cases were included. It was used the technique of immunohistochemistry Estreptoavitina-Biotin with HIF-1 antibody (Abcam mark, 1:200 dilution, 60 min pH6 citrate antigen retrieval Pascal) analysis of 05 fields each case at 400X magnification. The number of cells in each of five fields was added and the sample was considered as a unit the percentage of positive cells immuno-HIF-1α nuclear and cytoplasmic as well as intensity thereof. The results were obtained and compared between groups by the Student and multifactor ANOVA followed by Bonferroni post-test t test, based on the significance levels of 5%. Results: Cytoplasmic expression of HIF-1α was observed in 58.4 Â 6.0% of the epithelial cells of the DEO and 77.8 Â 3.9% of the cells of the CEO, with a significant difference (p = 0.022). The percentage of cells positive for HIF-1α nuclear staining also showed significant difference (p = 0.021) between DEO (0.2 Â 0.1%) and CEO (2.4 Â 0.8). There was no significant difference between the percentage of cells with weak positive immunostaining in the cytoplasm between DEO and CEO (p = 0.337), however, a significant increase in the percentage of cells with moderate cytoplasm staining (p = 0.029) and strong (p = 0.031) between DEO and CEO. Conclusion: One increasing the expression, nuclear and cytoplasmic HIF-1α DEO to CEO was observed, suggesting their involvement in the early stages of oral carcinogenesis. Clinical Relevance: Seek understanding of the complex signaling pathways, as well as the tumor microenvironment, and different biological behaviors in oral cancer.

Com o objetivo de fornecer ferramenta para auxiliar no dimensionamento da subunidade em irrigação localizada, especificamente para o método de irrigação por gotejamento, foi desenvolvido um Modelo Computacional, para o ambiente Windows em linguagem Visual Basic. Este modelo permitirá que esses sistemas de irrigação possam ser dimensionados sem negligenciar a perda localizada de carga ocasionada pela inserção dos emissores nas linhas laterais e pela inserção das linhas laterais nas linhas de derivação, o que muitas vezes causa desbalanço hidráulico destes sistemas. O modelo considera todas as etapas do desenvolvimento do projeto de irrigação para dimensionamento da subunidade, as características agronômicas do solo, do clima e da cultura, determinando-se condições de armazenamento da água no solo, a evapotranspiração e o ciclo de desenvolvimento da cultura. Para o dimensionamento da subunidade o modelo utiliza parâmetros como, declividade do terreno, pressão de entrada na linha, espaçamento entre emissores e linhas laterais, diâmetro da linha lateral, comprimento da linha de derivação, variação máxima de carga de pressão na lateral e variação máxima de vazão dos emissores. Estes dois últimos parâmetros considerados como critério de projeto. Por último, as características do emissor, sua vazão e área de protrusão, assim como o conector utilizado na conexão da linha lateral com a linha de derivação, que determinarão as perdas localizadas de carga. Com esses parâmetros o modelo determina e fornece como resultado, de forma ágil e precisa, o comprimento máximo da linha lateral pelo método da aproximação hidráulica, a perda localizada de carga, ocasionada pela inserção dos emissores na linha, expresso em termos de comprimento equivalente, os diâmetros para a linha de derivação, a perda localizada de carga, ocasionada pela inserção dos conectores na linha de derivação e o numero de linhas laterais conectadas na linha de derivação. Apresentando a tabela do dimensionamento da linha e o gráfico do perfil de pressão. Nos dimensionamentos realizados, utilizando os tipos de emissores existentes na base de dados do modelo, o emissor que proporcionou maior perda localizada de carga, em termos de comprimento equivalente, foi o emissor in-line (Uniram) com 0,758 m, resultando acréscimo do comprimento da linha lateral em 197,25 m, se desconsideradas as perdas localizadas de carga. O emissor que resultou menor acréscimo nas perdas localizadas de carga foi o do tipo online (Katif), com 0,11 m de comprimento equivalente, correspondendo 29 m de acréscimo no comprimento da linha lateral se desconsideradas as perdas localizadas de carga. Portanto, o modelo permite realizar as comparações do dimensionamento da subunidade considerando e desconsiderando as perdas localizadas de carga, possibilitando observar as diferenças resultantes no dimensionamento da subunidade quando negligenciadas estas perdas. / This research had the objective to develop a tool to design drip irrigation systems subunit. The computational model was developed to Windows in Visual Basic language. The model takes into account in the design both the local head loss due to the insertion of emitters in the lateral line and the insertion the lateral line in the main line. These local head losses are responsible for hydraulic unbalance of this type of irrigation system. The model considers all irrigation project steps for design of a sub-unit: soil properties, climate and crop characteristics. The model determines soil water content, evapotranspiration and crop cycle stage. In the sub-unit design, the model utilizes some parameters, such as, slope, pressure head in the main line, space between emitters and lateral lines, lateral line diameter, length of derivation line, maximum variation of pressure head in the lateral line, and maximum variation of emitters discharge. Emitter characteristics, its discharge and protrusion area, connector used to connect the lateral line into the derivation line, are also taken into account in the model. The model with previous parameters determines and provides precisely results of: maximum length of lateral line by hydraulic approximation method; local head losses, due to emitter insertion into lateral line, expressed as equivalent length losses; derivation line diameter; local head loss, due to connector insertion in the derivation line; and number of lateral line connected in the derivation line. It shows a design table and pressure profile. It was utilized some emitter types in the model database. The in-line emitter (Uniram) showed the biggest local head losses, 0,758 m in terms of equivalent length, it resulted in a increment in the lateral line length of the 197,25 m compared to lateral line without consider the local losses. Emitter online type (Katif) showed the lowest local head losses, 0,11 m of equivalent length which correspond 29 m in the lateral line length. Therefore, the model allows to compare the differences in the sub-unit design when it is considered the local head losses with the sub-units design neglecting theses losses.

Made available in DSpace on 2014-08-20T13:32:49Z (GMT). No. of bitstreams: 1 tese_katia_leston_bacelo.pdf: 1389207 bytes, checksum: b5ad0bea30c73a3ecb9d5b196b2a8b64 (MD5) Previous issue date: 2013-12-10 / A major challenge for the development of vaccines based on purified or recombinant protein subunits, and synthetic peptides resides in the fact that these are poorly immunogenic and mobilize insufficient immunoprotective response. Adjuvants are often used in association with these subunits in order to amplify and direct the immune response induced. Nowadays, there is a wide range of compounds that demonstrate adjuvant activity, however, few are approved for human use, and these often fail to induce appropriate immune response against a particular pathogen. Thus, there is a need to develop new adjuvants that are safe, effective and represent an alternative to currently available. In the present study, we used as a model antigen the non- identical portion of the Leptospira LigA protein (Leptospiral immunoglobulin-like protein A), an outer membrane protein of great interest as a mediator pathogenic mechanisms, used in serological diagnosis and as experimental vaccines. This antigen was formulated with various adjuvants, and the formulations tested for their immunoprotective potential in hamsters, challenged with a virulent strain of L. interrogans serovar Copenhageni. For this, the LigAni protein was produced in recombinant form (rLigAni) using Escherichia coli as the expression system and associated to xanthan polysaccharide, in its variants xanthan pruni strains 106 (X1) and 101 (X2), commercial xanthan and also to oligodinucleotídeo CpG (CpG ODN), carbon nanotubes (CNTs) and aluminum hydroxide (Alhydrogel). Formulations containing rLigAni associated with xanthan polysaccharide and CNTs induced significant IgG antibody titers, comparable to that induced when the protein was associated with Alhydrogel. Protection against lethal challenge was observed in 100%, 100%, 67% and 50% of the hamsters immunized with rLigAni-X1, rLigAni- CpG-X1, rLigAni-Alhydrogel and rLigAni-X2, respectively (Fisher test P < 0.05). The preparations containing rLigAni associated with CNTs, although induced an antibody response, failed to confer immunoprotection. Additionally, xanthan and CNTs adjuvants were not toxic to Chinese hamster ovary (CHO) cells, in vitro. The results of this study indicate xanthan as a new adjuvant for subunit vaccines against leptospirosis, presenting the ability to potentiate the immune response against the antigen, besides biocompatibility and the possibility of reduction of number of doses required for protection. / O maior desafio para o desenvolvimento de vacinas baseadas em subunidades proteicas, recombinantes ou purificadas e peptídeos sintéticos, reside no fato destas serem pouco imunogênicas e mobilizarem uma resposta imunoprotetora insuficiente. Adjuvantes são utilizados associados a estas subunidades com o intuito de amplificar e direcionar a resposta imune induzida. Na atualidade, existe uma grande gama de compostos que demostram ação adjuvante, contudo, poucos são aprovados para uso humano, e estes muitas vezes falham em induzir resposta imune adequada contra determinado agente patogênico. Assim, existe a necessidade do desenvolvimento de novos adjuvantes que sejam seguros, efetivos e representem uma alternativa aos atualmente disponíveis. No presente estudo, utilizamos como antígeno modelo a porção não-idêntica da proteína LigA (Leptospiral immunoglobulin-like protein A) de Leptospira spp., uma proteína de membrana externa de grande interesse como mediadora de mecanismos de patogenicidade, utilizada em sorodiagnóstico e em vacinas experimentais. Esta proteína foi associada a diferentes adjuvantes, e as formulações testadas quanto ao seu potencial imunoprotetor em hamsters desafiados com cepa virulenta de Leptospira interrogans sorovar Copenhageni. Para isso, a proteína LigAni foi produzida em sua forma recombinante (rLigAni) utilizando Escherichia coli como sistema de expressão e associada ao polissacarídeo xantana, em suas variantes xantana pruni cepas 106 (X1) e 101 (X2), xantana comercial, e também ao oligodinucleotídeo CpG (CpG ODN), nanotubos de carbono (CNTs) e hidróxido de alumínio (Alhydrogel). Formulações contendo rLigAni associada ao polissacarídeo xantana e aos CNTs induziram títulos de anticorpos IgG significativos e comparáveis aos induzidos quando a proteína foi associada ao Alhydrogel. Proteção contra o desafio letal foi observada em 100%, 100%, 67% e 50% dos hamsters imunizados com rLigAni-X1, rLigAni-CpG-X1, rLigAni-Alhydrogel e rLigAni-X2, respectivamente (Fisher test P < 0,05). As preparações contendo rLigAni associada aos CNTs, embora tenham induzido resposta de anticorpos, falharam em conferir imunoproteção. Adicionalmente, os adjuvantes xantana e CNTs não se mostraram tóxicos em células de ovário de hamster Chinês (CHO), in vitro. Os resultados desse estudo apontam a xantana como um novo adjuvante para vacinas de subunidade contra leptospirose, apresentando a propriedade de potencializar a resposta imune contra o antígeno, além de biocompatibilidade e a possibilidade de redução no número de doses requeridas para proteção.

Made available in DSpace on 2014-08-20T13:32:50Z (GMT). No. of bitstreams: 1 dissertacao_itaua_leston_araujo.pdf: 980896 bytes, checksum: 4007b4d62827e236b56c4fe512f94f29 (MD5) Previous issue date: 2014-02-27 / Glycoprotein D (gD) is essential for attachment and penetration of bovine herpesvirus type 5 (BoHV-5) into susceptible cells, and is a major target of host immune systems, inducing strong humoral and cellular immune responses. The immunogenicity of recombinant BoHV-5 (rgD5) expressed in Pichia pastoris was evaluated in bovines. Vaccines formulated with 100 μg rgD5 dose and adjuvants (Montanide ISA50V2 or Aluminum Hydroxide) with or without inactivated BoHV-5 or rgD5 without adjuvants were administered intramuscularly. A commercial vaccine was also used as control. The vaccine formulation rgD5 + ISA50V2 stimulated humoral immune responses after two doses, and higher titer of neutralizing antibodies were obtained in all three oil-based adjuvants formulations when compared to Hydroxide Aluminium adjuvant or the commercial vaccine. The vaccine BoHV-5 + rgD5 + ISA50V2 stimulated titers of neutralizing antibodies approximately 8 log2, which demonstrated higher correlations on the Indirect ELISA. Together, the results suggest that the recombinant gD5 conserved neutralizing epitopes and was able to stimulate a efficient humoral immune response in bovines. / A glicoproteína D (gD) é essencial para ligação e penetração de herpesvírus bovino 5 (BoHV-5) em células suscetíveis, e é um alvo importante do sistema imune do hospedeiro, induzindo respostas imunes humoral e celular. A imunogenicidade da glicoproteína D recombinante de BoHV-5 (rgD5) expressa em Pichia pastoris foi avaliada em bovinos. Vacinas formuladas com 100 μg de rgD5 por dose e adjuvante a base de óleo (Montanide ISA50V2) ou hidróxido de alumínio, com ou sem adição de BoHV-5 inativado foram administradas via intramuscular, e uma vacina comercial utilizada como controle. A vacina rgD5 + ISA50V2 estimulou resposta imune humoral após duas doses, e os mais elevados títulos de anticorpos neutralizantes foram obtidos em todas as três formulações de adjuvantes à base de óleo quando comparado com a formulação de vacinas de adjuvante de hidróxido de alumínio e vacina comercial. A vacina BoHV-5 + rgD5 + ISA50V2 estimulou títulos de anticorpos neutralizantes aproximadamente a 8 log2, demonstrando correlação significativa com o ELISA indireto. Em conjunto, os resultados sugerem que a rgD5 conservou epítopos neutralizantes e foi capaz de estimular uma resposta imune humoral eficiente em bovinos.

Juvenile neuronal ceroid lipofuscinosis (JNCL, aka. juvenile Batten disease or CLN3 disease), a lethal pediatric neurodegenerative disease without cure, often presents with vision impairment and characteristic ophthalmoscopic features including focal areas of hyper-autofluorescence. In the associated research article “Loss of CLN3, the gene mutated in juvenile neuronal ceroid lipofuscinosis, leads to metabolic impairment and autophagy induction in retinal pigment epithelium” (Zhong et al., 2020) [1], we reported ophthalmoscopic observations of focal autofluorescent lesions or puncta in the Cln3Δex7/8 mouse retina at as young as 8 month old. In this data article, we performed differential interference contrast and confocal imaging analyses in all retinal layers to localize and characterize these autofluorescent lesions, including their spectral characteristics and morphology. We further studied colocalization of these autofluorescent lesions with the JNCL marker mitochondrial ATP synthase F0 sub-complex subunit C and various established retinal cell type markers.

Voltage-gated calcium (Cav) channels are a prerequisite for signal transmission at the first olfactory sensory neuron (OSN) synapse within the glomeruli of the main olfactory bulb (MOB). We showed previously that the N-type Cav channel subunit Cav2.2 is present in the vast majority of glomeruli and plays a central role in presynaptic transmitter release. Here, we identify a distinct subset of glomeruli in the MOB of adult mice that is characterized by expression of the P/Q-type channel subunit Cav2.1. Immunolocalization shows that Cav2.1+ glomeruli reside predominantly in the medial and dorsal MOB, and in the vicinity of the necklace glomerular region close to the accessory olfactory bulb. Few glomeruli are detected on the ventral and lateral MOB. Cav2.1 labeling in glomeruli colocalizes with the presynaptic marker vGlut2 in the axon terminals of OSNs. Electron microscopy shows that Cav2.1+ presynaptic boutons establish characteristic asymmetrical synapses with the dendrites of second-order neurons in the glomerular neuropil. Cav2.1+ glomeruli receive axonal input from OSNs that express molecules of canonical OSNs: olfactory marker protein, the ion channel Cnga2, and the phosphodiesterase Pde4a. In the main olfactory epithelium, Cav2.1 labels a distinct subpopulation of OSNs whose distribution mirrors the topography of the MOB glomeruli, that shows the same molecular signature, and is already present at birth. Together, these experiments identify a unique Cav2.1+ multiglomerular domain in the MOB that may form a previously unrecognized olfactory subsystem distinct from other groups of necklace glomeruli that rely on cGMP signaling mechanisms.