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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.
171

Estudo e caracterização bioquímica e biologíca do veneno da serpente Bothrops moojeni e mecanismo antiveneno do plasma desses animais. / Bothrops moojeni\'s snake venom and plasma anti-venom mechanisms: a biochemical and biological characterization.

Weslei da Silva Aguiar 08 November 2016 (has links)
Foi observado no Laboratório de Herpetologia do Instituto Butantan que indivíduos da espécie Bothrops moojeni, quando acidentados entre si, apresentavam casos de mortalidade ocasionados por efeitos do envenenamento. Um modelo composto de análises bioquímicas e biológicas de 13 amostras de veneno e plasma de serpentes B. moojeni foi utilizado. SDS-PAGE mostrou perfis proteicos bem distintos para as amostras de veneno, e não para as de plasma. Western Blottings (WB) com amostras desses plasmas mostraram uma zona de detecção na faixa de 25 kDa em alguns indivíduos. Outro teste de WB, cruzando amostras de plasmas e venenos, mostrou que alguns indivíduos possuem proteínas que se ligam à estas regiões do plasma, o que não ocorre com o veneno dos outros indivíduos testados. Espectrometria de massas mostrou que esses indivíduos apresentam maiores concentrações proteicas e outras tantas exclusivas, incluindo inibidores de fosfolipases. A Dose Letal 50% mostrou uma maior eficiência nesses venenos, enquanto que a Dose Mínima Hemorrágica se mostrou inferior. Conclui-se que alguns indivíduos dessa espécie apresentam diferenças na composição dos seus venenos que se tornam significativas para o envenenamento. / It was observed in the Herpetology Laboratory of the Butantan Institute that individuals of the species Bothrops moojeni, when injured among themselves, presented cases of mortality caused by the effects of envenoming. A model composed of biochemical and biological analyzes of 13 venom and plasma samples of B. moojeni snakes was used. SDS-PAGE showed very different protein profiles for the venom samples, and not for the plasma ones. Western Blottings (WB) with samples of these plasmas showed a detection zone in the range of 25 kDa in some individuals. Another WB test, cross-linking plasma and venom samples, showed that some individuals have proteins that bind to these regions of the plasma, which does not occur with the venom of the other individuals tested. Mass spectrometry results showed that these individuals have higher protein and other unique concentrations, including phospholipase inhibitors. The Lethal Dose 50% showed a higher efficiency in these venoms, whereas the Minimum Hemorrhagic Dose was inferior. It is concluded that some individuals of this species present differences in the composition of their poisons that become significant for the envenoming process.
172

Estudo comparativo das características bioquímicas e biológicas do veneno da serpente Bothrops atrox (Linnaeus, 1758) (Serpente: Viperidae, Crotalinae) em indivíduos machos e fêmeas irmãos. / Comparative study of the biochemical and biological characteristics of the venom of Bothrops atrox (Linnaeus, 1758) (Serpentes: Viperidae, Crotalinae) in male and female siblings.

Cesar Adolfo Bravo Tobar 31 October 2016 (has links)
A Bothrops atrox é uma serpente de amplia distribuição na Sul América e é responsável por um número importante de mortes de pessoas, principalmente na Amazônia. As alterações na composição do veneno desta espécie têm sido associados a fatores como a ontogenia, distribuição geográfica e alimentação. Assim, este projeto visa comparar e identificar a partir da diferença entre os sexos, as características bioquímicas e biológicas do veneno de irmãos de B. atrox, sob condições ambientais controladas, contribuindo no conhecimento das mudanças nas características do veneno da espécie e pudendo auxiliar no aprimoramento da produção de antissoros mais efetivos. Os venenos foram coletados de 5 fêmeas e 4 machos irmãos de B. atrox, nascidas em cativeiro. Os venenos foram analisados quanto individualmente como o pool de cada grupo. As análises consistiram em dosagem de proteína através de BCA, eletroforese mono e bidimensional, cromatografia liquida, espectrometria de massas, atividades caseinolítica, fosfolipásica A2, L-aminoácido oxidase, zimografias contendo gelatina e caseína como substrato, dose mínima coagulante sobre o plasma e fibrinogênio, dose leta 50% e dose mínima hemorrágica. A análise individual dos venenos mostrou que os machos apresentaram maior concentração de proteínas e atividade fosfolipásica A2. No quanto aos pools de veneno, o das fêmeas apresentou maior letalidade e capacidade coagulante sobre plasma e fibrinogênio e o dos machos apresentaram maior capacidade hemorrágica e atividade L-aminoácido oxidase. O perfil espectrométrico mostrou que o pool de veneno das fêmeas, teve um 29% a mais na quantidade de proteínas identificadas em relação aos machos. Em conclusão, a ação do veneno das fêmeas estaria relacionado a uma maior capacidade para gerar dano sistêmico na presa, entanto que os venenos dos machos poderiam ocasionar um maior dano local. Além, a variabilidade nas atividades biológicas dos venenos confirma que além dos fatores ambientais existem outros que poderiam influir na plasticidade da composição dos venenos. / Bothrops atrox snake is widespread in South America and causing a large number of human deaths, mainly in the Amazon. Changes in the composition of the venom of this species have been linked to factors such as ontogeny, geographical distribution and feeding. Thus, this study aims to compare and identify from the sex difference, the biochemical and biological characteristics of venom of B. atrox siblings, under controlled environmental conditions, contributing to the knowledge of changes in the characteristics of the venom of the species and can assist in improving the production of more effective antisera. Venoms were collected from 5 females and 4 males of B. atrox siblings, born in captivity. The venoms were analyzed both, individually and as a pool of each group. The assays consisted in protein quantification using BCA, one and two-dimensional electrophorese, liquid chromatography, mass spectrometry, caseinolytic, phospholipase A2, and L-amino acid oxidase activities, zimography containing gelatin and casein as substrate, minimum coagulant dose upon plasma and fibrinogen, lethal dose 50 % and minimum hemorrhagic dose. Individual analysis of venoms showed that males had higher proteins concentration and phospholipase A2 activity. Concerning the venoms pool, the female showed higher lethality and coagulant capacity upon plasma and fibrinogen and the male had higher L-amino acid oxidase activity and hemorrhagic capacity. Spectrometric profile showed that the venom pool of female snakes had a 29 % increase in the number of proteins identified in comparison to males. In conclusion, the action of the female venom would be related to a higher capacity to generate systemic damage in the prey and male venoms could lead to higher local damage. In addition, variability in the biological activities of venoms confirms that there are other factors that could would be influencing the plasticity of the composition of venoms, in addition to environmental.
173

Evaluation multi-échelle de toxines de venins comme agents antinociceptifs potentiels / Multiscale evaluation of venom toxins as potential antinociceptive agents

Gonçalves, Tânia Cristina 19 December 2018 (has links)
L’objectif de ma thèse était d’identifier, comme agents antinociceptifs potentiels, des toxines de venins originales par leur séquence et/ou leur provenance. Dans cette optique, un criblage à haut débit de deux banques de venins a été réalisé par des méthodes électrophysiologiques de "patch-clamp" automatique, sur des lignées cellulaires exprimant le sous-type neuronal hNaV1.7 de canaux sodium (versus celles exprimant le sous-type cardiaque hNaV1.5), une cible antidouleur validée génétiquement et fortement exprimée au niveau des neurones sensoriels primaires des ganglions de la racine dorsale, premier support de la transmission du message nociceptif.Le criblage de la première banque de venins (appartenant à Smartox Biotechnology) a permis l’identification et la caractérisation, par des approches structurales et fonctionnelles multi-échelles (de la cellule in vitro à l’organisme in vivo), de 2 peptides de venins d’araignées ayant des propriétés potentiellement antinociceptives : (1) la cyriotoxine-1a du venin de Cyriopagopus schioedtei, dont les propriétés fonctionnelles sont proches de celles des peptides appartenant à la famille 1 des toxines d’araignées inhibant les canaux sodium, et (2) la poecitoxine-1a du venin de Poecilotheria subfusca, qui présente une meilleure affinité pour le sous-type hCaV1.2 de canaux calcium que pour le sous-type hNaV1.7. Nous avons également mené une étude de "structure-activité" afin d’améliorer le profil de sélectivité de la phlotoxine-1 d’une araignée Phlogiellus, connue pour son activité antinocieptive. Finalement, nous avons mis en évidence une interaction directe entre l’huwentoxine-IV, déjà connue comme agent antinociceptif potentiel, et le sous-type neuronal NaV1.6, responsable d’effets neuromusculaires indésirables. Le criblage de la deuxième banque de venins (appartenant à SANOFI) a permis d’identifier des hits intéressants provenant de venins d’araignées et de scorpions non étudiés jusqu’à présent et ayant une séquence originale présentant peu d’homologie avec les séquences déjà connues. / The aim of my thesis was to identify original venom toxins, by their sequence and/or origin, as potential antinociceptive agents. In this context, a high-throughput screening of two venom libraries was performed, by automated patch-clamp electrophysiology, on cell lines expressing the hNaV1.7 neuronal subtype of sodium channels (versus those expressing the hNaV1.5 cardiac subtype), a genetically-validated and strongly expressed pain target in the primary sensory neurons of dorsal root ganglia, the first support of nociceptive message transmission.The screening of the first venom library (belonging to Smartox Biotechnology) allowed the identification and characterization, by structural and multiscale functional approaches (from the cell in vitro to the organism in vivo), of 2 peptides from spider venoms having potential antinociceptive properties : (1) cyriotoxin-1a from Cyriopagopus schioedtei venom, whose functional properties are close to those of peptides belonging to family 1 of spider toxins inhibiting sodium channels, and (2) poecitoxin-1a from Poecilotheria subfusca venom, which has a better affinity for the hCaV1.2 subtype of calcium channels than for the hNaV1.7 subtype. We also conducted a "structure-activity" study to improve the selectivity profile of phlotoxin-1 from a Phlogiellus spider, known for its antinociceptive activity. Finally, we evidenced a direct interaction between huwentoxin-IV, already known as a potential antinociceptive agent, and the NaV1.6 neuronal subtype which is the main cause of undesirable neuromuscular effects. The screening of the second venom library (belonging to SANOFI) allowed to identify interesting hits from spider and scorpion venoms, not studied until now, having an original sequence with little homology with already known sequences.
174

Interaction immunitaire dans un modèle Drosophiles-parasitoïde : effet de la température et potentiel évolutif du venin en lien avec l’espèce hôte / Immune interaction in a Drosophila-parasitoid model : effect of the temperature and evolvability of the venom in relation to the host species

Cavigliasso, Fanny 22 December 2017 (has links)
Les larves des insectes endoparasitoïdes se développent aux dépens d’un hôte, conduisant à sa mort. Leur réussite dépend de leur capacité à neutraliser la réponse immunitaire de l’hôte (formation d’une capsule mélanisée) et réguler sa physiologie, via l’injection de venin lors de l’oviposition. Bien que les parasitoïdes subissent des changements importants de leur environnement, son impact sur la composition protéique de leur venin a rarement été étudié. Dans cette thèse, j’ai étudié (i) l’impact de la température sur l’interaction immunitaire Drosophile – Leptopilina boulardi et la composition de son venin et (ii) le potentiel évolutif du venin en réponse à différents hôtes. La température influe sur le succès parasitaire de L. boulardi via la capacité de l’hôte à encapsuler et/ou celle du parasite à s’échapper de la capsule. De plus, il y a une plasticité de la composition du venin avec la température. Par ailleurs, une 1ère évolution expérimentale a montré une évolution rapide de composition du venin en réponse à la résistance/sensibilité de l’hôte et un coût à la présence de certains facteurs du venin. La 2nd évolution expérimentale sur des espèces hôtes différentes suggère (i) une spécialisation des parasitoïdes sur l’hôte d’élevage et (ii) une évolution différentielle de la réussite parasitaire (virulence) et de la composition du venin. Le venin assurant la réussite sur différents hôtes contiendrait donc une combinaison de protéines « spécialisées » pour chaque hôte et des protéines à effet « large-spectre » sur certains hôtes testés. Les résultats suggèrent un fort potentiel adaptatif des parasitoïdes en réponse à différents paramètres biotiques et abiotiques. / Endoparasitoid wasp larvae develop at the expense of a host, leading to its death. Their success depends on their ability to overcome the immune response of the host (formation of a melanized capsule) and regulate its physiology, via the injection of venom upon oviposition. Although parasitoids undergo significant changes in their environment, its impact on the protein composition of their venom has rarely been tested. In this thesis, I studied (i) the impact of temperature on the Drosophila - Leptopilina boulardi immune interaction and the composition of its venom and (ii) the evolutionary potential of venom in response to different hosts. Temperature influences the parasitic success of L. boulardi via the ability of the host to encapsulate and / or that of the parasite to escape from the capsule. Besides, there is a plasticity of the venom composition with temperature. A first experimental evolution showed a rapid evolution of the composition of the venom in response to the resistance / susceptibility of the host, and a cost to the presence of certain factors of the venom. The second experimental evolution on different host species suggests (i) a specialization of parasitoids on the rearing host and (ii) a differential evolution of the parasite success (virulence) and the composition of the venom. The venom ensuring success on different hosts would therefore contain a combination of "specialized" proteins for each host as well as "broad-spectrum" effect proteins on some hosts tested. The results suggest a strong adaptive potential of parasitoids in response to different biotic and abiotic parameters.
175

Effects of a Commercially Available Energy Drink on Anaerobic Performance

Downing, Jason J 17 July 2009 (has links)
In an attempt to improve aerobic and anaerobic performance, athletes and fitness enthusiasts consume a variety of supplements. Because of this, energy drinks are quickly becoming more and more popular every day. Despite its highly addictive nature, caffeine, which is the main active ingredient in energy drinks, is gaining recognition as an ergogenic aid. However, due to the many factors that affects the action of caffeine, and because the research on caffeine and anaerobic performance is limited, the potential for studying energy drinks and anaerobic performance is quite large. PURPOSE: To determine if a commercially available energy drink has any ergogenic effects on lower body and upper body resistance exercise performance. METHODS: In a block randomized, double-blind, placebo-controlled, crossover study thirteen recreationally trained male and female volunteers (mean ± SD age = 22.5 ± 3.4 years) performed 4 sets of the leg press and 4 sets of the bench press exercises (at 80% of 1 RM with all sets separated by 2 minutes). Acting as their own controls, participants were tested on each dependent variable (i.e., bench press total volume, leg press total volume and total workout volume) twice, after ingesting a Venom® Energy Drink and after ingesting a placebo drink. RESULTS: Data were tested via a dependent samples t-test with p value set at < 0.05. No significant differences were found for any of the three dependent variables. DISCUSSION: The major finding of this study is that consumption of a Venom® Energy Drink does not produce an ergogenic effect by improving anaerobic exercise performance when the exercises are performed forty-five minutes following ingestion. Future studies should focus more on examining the factors behind the actions of caffeine. More specifically, the exercise performed, the training status of the participants, individual differences of the participants, and the dose of caffeine.
176

Characterization of bioactive peptides without disulfide bridges from the venom of Lycosa poonaensis species inhabiting the Egyptian environment / エジプト地域に棲息するLycosa poonaensisの毒液に含まれるジスルフィド結合を持たない生理活性ペプチドの構造決定

Megaly, Alhussin Mohamed Abdelhakeem 26 September 2022 (has links)
京都大学 / 新制・課程博士 / 博士(農学) / 甲第24241号 / 農博第2520号 / 新制||農||1094(附属図書館) / 学位論文||R4||N5412(農学部図書室) / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 宮川 恒, 教授 三芳 秀人, 教授 森 直樹 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
177

Evolution of Rattlesnake Venom involves Geographically Structured Coevolution and Local Adaptation to Prey

Holding, Matthew Landon 23 October 2017 (has links)
No description available.
178

Effects of temperature on hunting performance of an ectothermic venomous predator (Gloydius blomhoffii, Viperidae) / 外温性有毒捕食者ニホンマムシ(クサリヘビ科)の捕食パフォーマンスにおける温度の効果

Kodama, Tomonori 25 March 2024 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第25140号 / 理博第5047号 / 新制||理||1719(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 森 哲, 教授 中務 真人, 准教授 城野 哲平 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
179

Isolamento e caracterização de toxinas do veneno de Bothrops alcatraz Marques, Martins e Sazima, 2002 e aspectos coevolutivos com a dieta / Isolation and characterization of toxins of Bothrops alcatraz Marques, Martins e Sazima, 2002 venom and coevolutive aspects with diet

Narvaes, Laura Virginia Pereira 18 April 2007 (has links)
Os venenos de serpentes são misturas complexas com composição variada, possuindo constituintes orgânicos e inorgânicos. Dentre os compostos orgânicos, destacam-se as proteínas, tóxicas e/ou com altas atividades enzimáticas. Desta forma, os venenos desenvolvem importante papel na captura de presas e auxílio à digestão. Venenos de serpentes da família Viperidae apresentam ampla e variada gama de ações biológicas, como proteólise, coagulação, hemorragia, neurotoxicidade e miotoxidade. Populações de serpentes habitantes endemicamente em ilhas são bons modelos para estudos de evolução, especialmente quando comparadas a espécies de mesmo gênero que habitam o continente. Espécies ancestrais de serpentes do gênero Bothrops sofreram isolamento geográfico cerca de 9 mil anos atrás, quando no Período Pleistoceno porções de terra na região Sudeste do Brasil foram isoladas do continente, levando a formação de ilhas costeiras, devido a elevação do nível do mar. Tal isolamento deu origem a novas espécies insulares pertencentes ao gênero Bothrops. Estudos relacionados aos venenos destas espécies, suas especificidades e diferenças com relação a serpentes continentais são escassos. O Arquipélago de Alcatrazes localiza-se no litoral de São Paulo, distando aproximadamente 35 Km da costa. Não há relatos da existência de mamíferos na ilha, com exceção de morcegos. Serpentes adultas da espécie Bothrops alcatraz, endêmica da Ilha de Alcatrazes, apresentam características encontradas em serpentes juvenis do grupo das jararacas, como a dieta baseada exclusivamente em animais ectotérmicos e a composição diferenciada do veneno. O presente trabalho tem como objetivo caracterizar as principais ações do veneno da serpente B. alcatraz, espécie endêmica e ilhoa, isolando cromatograficamente suas frações. Resultados indicam no veneno de B. alcatraz apresenta as atividades coagulante sobre plasma humano, fosfolipásica, miotóxica e edematogênica mais ativas quando comparadas com as ações do veneno de B. jararaca do continente. As ações proteolítica, hemorrágica e toxicidade para camundongos são mais potentes no veneno de B. jararaca. A presença de ação neurotóxica específica para artrópodes no veneno de B. alcatraz sugere a ação de uma fosfolipase A2, a qual foi isolada cromatograficamente. As propriedades e composição do veneno de B. alcatraz indicam uma provável evolução de toxinas adaptadas a seu tipo de presa/alimento. / Snakes venoms are complex mixtures with varied composition constituted by organic and inorganic molecules. The main organic components are proteins, which can be toxic and show high enzymatic activities, thus playing important role in prey capture and digestion in snakes. Viperidae snakes family show wide range of biological actions, as proteolytic, coagulant, hemorrhagic, neurotoxic and myotoxic activities. Snake populations inhabiting endemically islands are useful models for evolution studies, specially when compared to their congeneric continental species. Bothrops species ancestors from Southeastern Brazil underwent geographic isolation about 9 thousand years ago, during the Pleistocene Period, when land portions were separated from the continent by the sea. The isolation originated new (island endemic) Bothrops species. Studies related to those snake venoms, its specialties and differences among continental species of the genera Bothrops are scarce. The Alcatrazes Archipelago is located in São Paulo coast, 35 kilometer far from the continent. There are no register of mammals in those islands, except for bats. Bothrops alcatraz is endemic from the Alcatrazes Island. Adults show some similarities to young specimens from the continental jararaca group. They feed exclusively on ectothermic animals and their venom shows a different composition. The aim of this study was to analyze the endemic island snake, B. alcatraz, venom, isolating by chromatography the venom fractions. Results indicated that B. alcatraz venom presents coagulant, phospholipase, myotoxic and edema forming activities higher than continental B. jararaca venom. The proteolytic, haemorrhagic and mice toxicity are higher on B. jararaca venom. The specific neurotoxic action in arthropods of B. alcatraz venom suggests a phospholipase A2 action, which was isolated bt cromatography. The properties and composition of B. alcatraz venom indicates a possible evolution of toxins adapted to the prey kinds.
180

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.

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