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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.
1

Peptídeos antimicrobianos da hemolinfa do escorpião: Tityus serrulatus. / Antimicrobial peptides from the hemolymph of the scorpion: Tityus serrulatus.

Oliveira, Thiago de Jesus 05 October 2016 (has links)
Em artrópodes o sistema imune inato contribui para a adaptação de animais como os escorpiões à diferentes ambientes. Esse sistema é composto por mecanismos capazes de agir contra injúrias e a ação de microrganismos e entre esses mecanismos estão os peptídeos antimicrobianos (PAMs). O objetivo deste trabalho foi identificar PAMs presentes na hemolinfa de Tityus serrulatus. Para isso sua hemolinfa foi extraída e separados os hemócitos e plasma, em seguida fracionamos em 3 concentrações de acetonitrila em TFA 0,05% (05, 40 e 80%). Estas frações foram submetidas a uma cromatografia liquida de alta eficiência (CLAE) e os picos foram avaliados quanto a sua ação antimicrobiana e hemolítica. Foram identificadas 16 frações que apresentam atividade antimicrobiana. Uma das frações com atividade antimicrobiana, presente nos hemócitos apresentou similaridade com defensina descrita em carrapatos da espécie Ixodes scapularis. Essa fração possui aproximadamente 3486 Da, não apresenta atividade hemolítica e foi denominada como Serrulina. / In arthropods, its innate immune system contributes to the adaptation of animals like scorpions to different environments. This system consists of mechanisms that act avoiding injuries and against the action of microorganisms, among these mechanisms are antimicrobial peptides (AMPs). The aim of this study was to identify AMPs, present in the hemolymph of Tityus serrulatus. The hemolymph was extracted and then we separated hemocyte and plasma. The samples were fractionated in different concentrations of acetonitrile in TFA 0.05% (05, 40 and 80%). These fractions were subjected to high-performance liquid chromatography (HPLC) and the peaks obtained were evaluated for its antimicrobial and hemolytic action. We found sixteen fractions with antimicrobial activity. One of the fractions with antimicrobial activity, present in hemocytes, is similar with a defensin described in ticks, Ixodes scapularis. This fraction has about 3486 Da, has no hemolytic activity and was named as Serrulina.
2

Proteínas de resposta imune expressas na hemolinfa da Diatraea saccharalis (Lepidoptera: crambidae) em resposta a diferentes microrganismos / Immune response proteins expressed in the hemolymph of Diatraea saccharalis (Lepidoptera: crambidae) in response to different microrganisms

Corsato, Ana Cláudia Malagutti 05 March 2018 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2018-05-24T18:44:26Z No. of bitstreams: 2 Ana Cláudia Malagutti Corsato.pdf: 1319419 bytes, checksum: c4de080588607227096826021e800839 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-05-24T18:44:26Z (GMT). No. of bitstreams: 2 Ana Cláudia Malagutti Corsato.pdf: 1319419 bytes, checksum: c4de080588607227096826021e800839 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-05 / The Diatraea saccharalis is the pest responsible for a great economic loss to the cultivation of sugar cane. As well as others members of Lepidoptera order, the D. saccharalis has a fast and efficient immune innate response, characterized by primary defense barrier, cellular immune response and humoral immune response. The antimicrobial peptides (AMPs) are included in humoral immune response that show cationic and amphiphilic characteristics besides its low molecular weight, what makes them potentially therapeutic agents. In this study were analyzed proteins with low molecular weight differently expressed in the hemolymph of D. saccharalis, after the interval of six and twelve hours of humoral immune response induction with different microorganisms compared to non-challenged worms (control). The 5th instar worms were divided in groups (n= 50) and submitted to six and twelve hours of septic challenges: control (group 1), challenged by Bacillus subtilis ATCC 6623 (group 2), challenged by Escherichia coli ATCC 11229 (group 3), and challenged by Beauveria bassiana 88 strain (group 4). In each worm was inoculated a known concentration of microorganism, and after the established time, the hemolymph was collected. The low molecular weight proteins were obtained submitting each hemolymph sample to an extraction solution containing Methanol, Acetic Acid and Water. After that, the protein extracts were concentrated in columns and protein dosage was realized in 280 nm. About 500 μg of proteins were submitted to two-dimensional electrophoresis (2-DE). The spots were excised from gels, digested with Tripsin and submitted to MALDI-ToF/ToF type mass spectrometry. The identification of protein orthologs was realized using the obtained data against the data available on the MASCOT online server (Matrix science), with the database (NCBI and Swiss rot) specified for Drosophila melanogaster and an internal database of Lepidoptera. The TagIdent tool was utilized for searching proteins through their molecular weight and isoelectric point. It was possible to identify eighteen proteins, of which twelve demonstrated to be involved with immune response in D. saccharalis. The six hours septic challenge with B. subtilis was responsible for modification of expression of Peptidoglycan recognition protein (PGRP), for increase of expression of Chitin-binding protein and for induction of expression of proteins like the Attacin-A and the Serine-protease inhibitor-like. The six hours septic challenge with E. coli increased the expression of a putative defense protein. The twelve hours septic challenge using B. subtilis and E. coli were responsible for increase of expression of Lysozyme. The six hours septic challenge with B. bassiana induced of expression of a Cecropin A2 and a Drosomycin-like. On the order hand, after twelve hours of fungal challenge, there was the induction of expression of multifunctional protein Apolipophorin-3. It was concluded that the septic challenge with different microorganisms were capable of change the expression of some proteins involved in the immune response in D. saccharalis, significant for understanding this process as well as for pointing the substances with antimicrobial functions. / A Diatraea saccharalis é a praga responsável por grandes perdas econômicas à cultura da cana-de-açúcar. Assim como outros integrantes da ordem Lepidoptera, a D. saccharalis possui resposta imunológica inata rápida e eficiente, constituída por barreira primária de defesa, resposta imune celular e resposta imune humoral. Os peptídeos antimicrobianos (PAMs) são parte da resposta imune humoral que apresentam características catiônicas e anfifílicas, além de sua massa molecular baixa, o que os tornam potenciais agentes terapêuticos. Neste estudo foram analisadas proteínas com baixa massa molecular, diferencialmente expressas na hemolinfa da D. saccharalis, após os intervalos de 6 e 12 horas de indução da resposta imune humoral com diferentes microrganismos em comparação às lagartas não desafiadas (controle). As lagartas em 5º instar foram divididas em grupos (n= 50) e submetidas a desafios sépticos de 6 e 12 horas: controle (grupo 1), desafiadas por Bacillus subtilis ATCC 6623 (grupo 2), desafiadas por Escherichia coli ATCC 11229 (grupo 3) e desafiadas por Beauveria bassiana cepa 88 (grupo 4). Em cada lagarta foi inoculada uma concentração conhecida do microrganismo e, após o tempo estabelecido, a hemolinfa foi coletada. As proteínas de baixa massa molecular foram obtidas submetendo cada amostra de hemolinfa a uma solução de extração contendo Metanol, Ácido Acético e Água. Posteriormente, os extratos proteicos foram concentrados em colunas e a dosagem proteica realizada em 280 nm. Aproximadamente 500 μg de proteínas foram submetidas à eletroforese bidimensional (2-DE). Os spots foram retirados dos géis, digeridos com Tripsina, e submetidos à espectrometria de massas do tipo MALDI-ToF/ToF. A identificação das proteínas ortólogas foi realizada utilizando os dados obtidos contra os dados disponíveis no servidor online MASCOT (Matrixscience), especificando a base de dados (NCBI e Swissprot) para Drosophila melanogaster e um banco interno de Lepidoptera. A ferramenta TagIdent foi utilizada para a busca de proteínas por meio de suas massas moleculares e ponto isoelétrico. Foram identificadas dezoito proteínas, das quais doze se mostraram envolvidas com a resposta imune em D. saccharalis. O desafio séptico de 6 horas com B. subtilis foi responsável pela alteração na expressão da proteína de reconhecimento de peptideoglicano (PGRP), pelo aumento da expressão da proteína ligadora de quitina e pela indução da expressão de proteínas como a Atacina-A e a proteína inibidora de serino-protease. O desafio imunológico de 6 horas com E. coli levou ao aumento da expressão de uma provável proteína de defesa. Os desafios de 12 horas utilizando as bactérias B. subtilis e E. coli se mostraram responsáveis pelo aumento da expressão da Lisozima. O desafio de 6 horas com B. bassiana causou indução da expressão de uma Cecropina A2 e uma possível Drosomicina. Por sua vez, após o desafio fúngico de 12 horas, houve a indução da expressão da proteína multifuncional Apolipoforina-3. Concluiu-se que desafios sépticos com diferentes microrganismos foram capazes de alterar a expressão de algumas proteínas envolvidas na resposta imune em D. saccharalis, importantes para o entendimento deste processo e também para o apontamento de substâncias com funções antimicrobianas.
3

Peptídeos antimicrobianos da hemolinfa do escorpião: Tityus serrulatus. / Antimicrobial peptides from the hemolymph of the scorpion: Tityus serrulatus.

Thiago de Jesus Oliveira 05 October 2016 (has links)
Em artrópodes o sistema imune inato contribui para a adaptação de animais como os escorpiões à diferentes ambientes. Esse sistema é composto por mecanismos capazes de agir contra injúrias e a ação de microrganismos e entre esses mecanismos estão os peptídeos antimicrobianos (PAMs). O objetivo deste trabalho foi identificar PAMs presentes na hemolinfa de Tityus serrulatus. Para isso sua hemolinfa foi extraída e separados os hemócitos e plasma, em seguida fracionamos em 3 concentrações de acetonitrila em TFA 0,05% (05, 40 e 80%). Estas frações foram submetidas a uma cromatografia liquida de alta eficiência (CLAE) e os picos foram avaliados quanto a sua ação antimicrobiana e hemolítica. Foram identificadas 16 frações que apresentam atividade antimicrobiana. Uma das frações com atividade antimicrobiana, presente nos hemócitos apresentou similaridade com defensina descrita em carrapatos da espécie Ixodes scapularis. Essa fração possui aproximadamente 3486 Da, não apresenta atividade hemolítica e foi denominada como Serrulina. / In arthropods, its innate immune system contributes to the adaptation of animals like scorpions to different environments. This system consists of mechanisms that act avoiding injuries and against the action of microorganisms, among these mechanisms are antimicrobial peptides (AMPs). The aim of this study was to identify AMPs, present in the hemolymph of Tityus serrulatus. The hemolymph was extracted and then we separated hemocyte and plasma. The samples were fractionated in different concentrations of acetonitrile in TFA 0.05% (05, 40 and 80%). These fractions were subjected to high-performance liquid chromatography (HPLC) and the peaks obtained were evaluated for its antimicrobial and hemolytic action. We found sixteen fractions with antimicrobial activity. One of the fractions with antimicrobial activity, present in hemocytes, is similar with a defensin described in ticks, Ixodes scapularis. This fraction has about 3486 Da, has no hemolytic activity and was named as Serrulina.
4

Moléculas biotivas do veneno da aranha migalomorfa Avicularia juruensis. / Bioactive molecules from the venom of mygalomorph spider Avicularia juruensis.

Nascimento, Soraia Maria do 21 September 2016 (has links)
Venenos de aranhas podem ser boas fontes de moléculas com potencial terapêutico e biotecnológico. Sendo assim, esse estudo teve como objetivo analisar moléculas bioativas do veneno de Avicularia juruensis, com foco em PAMs e enzimas. O veneno foi extraído por estimulação elétrica e, através de CLAE-FR, ensaio de inibição do crescimento microbiano e LC-MS/MS, foram identificados e caracterizados 7 PAMs. Todos possuem o motivo nó de cistina do tipo ICK e têm similaridade com neurotoxinas de venenos de outras aranhas. O perfil eletroforético do veneno de A. juruensis indicou que ele possui moléculas com massa entre 130 e abaixo de 10 kDa. Utilizando LC-MS/MS e análise transcriptômica foi possível identificar 6 metaloproteinases. Elas possuem domínios conservados de proteínas do tipo ADAMs, MMPs e metalopeptidases astacina-like. A presença destas enzimas é, provavelmente, importante para a digestão extracorpórea, visto que esta aranha geralmente consome pequenas aves. O estudo de venenos de aranhas terafosídeas é essencial, visto que este é um grupo pouco estudado. / Spider venoms can be good sources of molecules with therapeutic and biotechnological potential. Thus, this study aimed to analyze bioactive molecules from venom of Avicularia juruensis, focusing on AMPs and enzymes. The venom was extracted by electrical stimulation. By RP-HPLC, liquid growth inhibition assay and LC-MS/MS, seven AMPs were identified and characterized. All these peptides have inhibitory cystine knot motif and they showed similarity with venom neurotoxins from others spiders. The electrophoretic profile of A. juruensis venom shows that it has molecules with molecular masses between 130 kDa and below 10 kDa. By LC-MS/MS and transcriptomic analysis yielded the identification of six metalloproteinases, which possess typical conserved domains from ADAMs, MMPs and astacin-like metallopeptidases. These metalloproteinases may be involved in a key role during preoral digestion. The study of Theraphosidae spider venom is essential, since this group is poorly studied.
5

Predição e desenho racional assistido por computador para bioprospecção de novos peptídeos antimicrobianos

Porto, William Farias 08 August 2017 (has links)
Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-08-14T21:36:36Z No. of bitstreams: 1 WilliamFariasPortoTese2017.pdf: 13965916 bytes, checksum: 627497be290e274ade4f2d64a0b0d119 (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-08-14T21:37:32Z (GMT) No. of bitstreams: 1 WilliamFariasPortoTese2017.pdf: 13965916 bytes, checksum: 627497be290e274ade4f2d64a0b0d119 (MD5) / Made available in DSpace on 2018-08-14T21:37:33Z (GMT). No. of bitstreams: 1 WilliamFariasPortoTese2017.pdf: 13965916 bytes, checksum: 627497be290e274ade4f2d64a0b0d119 (MD5) Previous issue date: 2017-08-08 / Antimicrobial peptides (AMPs) are part of the innate immune system. Genetic modifications can lead to the imbalance in the production of AMPs, which in turn, can lead to several inflammatory and/or infectious conditions. In this context, the identification and characterization of AMPs variants caused by point mutations are important to medical monitoring of bearers of such mutations; mainly due to the fact that the effectiveness of conventional antimicrobial agents has been reduced due to the development of resistance by bacteria, a breakthrough of new drugs is made. In this context, synthetic AMPs, generated through several rational design methods, have been proposed as an alternative. Thus, aiming at solutions to this scenario, the present work presents two new approaches, which consist of a model for the prediction of activities of variants of human defensins; and the computer-aided design of plant peptides. In the first approach, it was elaborated a system of median lethal dose prediction, correlating previously published data and the solvation potential energy of the variants. This model was applied to human defenses, HD5 and HBD1, which in turn showed that several variants may be less potent and consequently their carriers may be more susceptible to bacterial infections. In this way, in the second approach, the guava peptide, Pg-AMP1, was used as a model for the development of new synthetic peptides, the guavanins. Structural analyzes of Pg- AMP1 indicated an extremely flexible and variable structure. Thus, a genetic algorithm for computer-aided rational design was applied to obtain a more stable structure. The prototype, guavanin 2, presented α-helix structuring in hydrophobic environments, and showed 100% efficacy against Gram-negative bacteria at low concentrations through the rupture of the bacterial membrane and causing hyperpolarization of the same. In sum, the methodologies and the molecules developed here bring new perspectives for the treatment of infections. / Os peptídeos antimicrobianos (PAMs) fazem parte do sistema imune inato. Alterações genéticas podem levar ao desequilíbrio em sua produção, podendo gerar diversos quadros inflamatórios e/ou infecciosos. Neste contexto, a identificação e caracterização de variantes de PAMs geradas por mutações pontuais em seus respectivos genes são importantes para o acompanhamento médico dos portadores destas mutações; principalmente pelo fato de que a eficácia dos antimicrobianos convencionais está sendo reduzida devido ao desenvolvimento de resistência por parte das bactérias, tornando necessário o desenvolvimento de novos fármacos. Desta forma, PAMs sintéticos, gerados por meio de métodos de desenho racional, têm sido propostos como uma alternativa. Assim, visando desenvolver soluções para este cenário, o presente trabalho apresenta duas novas abordagens, que consistem em um modelo para predição de atividade de variantes de defensinas humanas; e o desenho assistido por computador de peptídeos de planta. Na primeira abordagem foi elaborado um sistema de predição de dose letal mediana correlacionando dados previamente publicados e a energia potencial de solvatação das variantes. Este modelo foi aplicado a defensinas humanas, HD5 e HBD1, indicando que diversas variantes são menos potentes e consequentemente seus portadores podem ser mais susceptíveis às infecções bacterianas. Neste sentido, na segunda abordagem, o peptídeo de goiaba, Pg-AMP1, foi utilizado como modelo para o desenvolvimento de novos peptídeos sintéticos, as guavaninas. As análises estruturais do Pg-AMP1 indicaram uma estrutura extremamente flexível e variável. Desse modo, um algoritmo genético para o desenho racional assistido por computador foi aplicado para a obtenção de uma estrutura mais estável. O protótipo, guavanina 2, apresentou estruturação em α-hélice em ambientes hidrofóbicos, e mostrou eficácia de 100% contra bactérias Gram-negativas em baixas concentrações através do rompimento da membrana bacteriana e causando hiperpolarização da mesma. Em suma, as metodologias e as moléculas desenvolvidas aqui trazem novas perspectivas para o tratamento de infecções.
6

Integrated network application management (INAM)

Nelson, Mark D. 12 1900 (has links)
Approved for public release, distribution is unlimited / This thesis attempts to create a desire for change in DoD's current approach to Network Application Management (NAM). The evolution of NAM into Integrated Network Application Management (INAM) is a crucial component of Network Centric Warfare and achieving Information Superiority and Interoperability. INAM is outlined as three functional requirements, which are Network Awareness, Mission Prioritization linkage to Network Resources, and the Balancing of Service Management. Scenarios play a key role in illustrating the new threats that DoD faces today. These scenarios also identify limitations and challenges to NAM as it exists today. These challenges require significant improvements in flexibility and responsiveness, while providing for wide integration. Trends supporting change are identified in this thesis. Two of the more important trends are the rise of Architectural and Object Oriented Development. Examples such as Training and Testing Enabled Architecture (TENA), Surveillance and Target Acquisition Network (STAN), and Virtual Proving Ground (VPG) are clear examples of these trends. The merging of the Computer Industry's efforts to expand the reach of Operating Systems with the traditional efforts from Network Management is also a trend that is examined. Organizations like Distributed Management Task Force (DMTF) are important to such examinations. Successful change can not be achieved without planning for the transition. This thesis also presents some active transition efforts addressing Network Centric Warfare. TENA, VPG and Naval Postgraduate School's Information Technology Management Master's Program provide three examples of addressing transition in DoD. / Civilian, United States Army Yuma Proving Ground
7

Mechanical design, dynamic modeling and control of hydraulic artificial muscles

Nikkhah, Arman 18 August 2020 (has links)
Artificial human muscles have traditionally been operated through pneumatic means, and are known as Pneumatic Artificial Muscles (PAMs). Over the last several decades, Hydraulic Artificial Muscles (HAMs) have also been investigated due to their high power-to-weight ratio and human-like characteristics. Compared to PAMs, HAMs typically exhibit faster response, higher efficiency, and superior position control; characteristics which provide potential for application in rehabilitation robotics. This thesis presents a new approach to actuate artificial muscles in an antagonistic pair configuration. The detailed mechanical design of the test platform is introduced, along with the development of a dynamic model for actuating an artificial elbow joint. Also, custom manufactured Oil-based Hydraulic Artificial Muscles (OHAMs) are implemented in a biceps-triceps configuration and characterized on the test platform. Furthermore, an integrator-backstepping controller is derived for HAMs with different characteristics (stiffness and damping coefficients) in an antagonistic pair configuration. Finally, simulations and experimental results of the position control of the artificial elbow joint are discussed to confirm the functionality of the OHAMs utilizing the proposed actuating mechanism and the effectiveness of the developed control algorithm. / Graduate

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