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1
Duboucher, Christophe. "Contribution à l'étude des trichomonoses pulmonaires." Lille 2, 2007. http://www.theses.fr/2007LIL2S034.
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A ce jour, les trichomonadines (appelées communément trichomonas) n'ont qu'une place très limitée en pathologie humaine, à l'exception de Trichomonas vaginalis (T. Vaginalis) au niveau du tractus génito-urinaire. La présence de trichomonadines dans les voies respiratoires a parfois été signalée chez des patients présentant des pathologies broncho-pulmonaires chroniques. Ayant été confrontés à quelques cas privilégiés de la sphère ORL puis de la pathologie respiratoire, il nous est apparu que la situation était tout à fait différente. Tout d'abord, nous avons étudié la prévalence de l'infection à trichomonadines chez les patients atteints de pneumonie à Pneumocystis jirovecii. Les cytospins de lavages bronchoalvéolaires archivés sur une période de 10 ans ont été revues. De façon surprenante, il est apparu que l'association des deux agents pathogènes y est fréquente: 60% de l'ensemble des PcP sont co-infectées. L'association apparaît systématique dans le PcP riches en Pneumocystis (réf 2 et 7). La maladie pulmonaire "pneumonie à pneumocystis" (PcP) peut donc être considérée comme une co-infection à Pneumocystis et à trichomonadine. Le développement de la trichomonadine au sein de l'alvéole pulmonaire ne serait pas lié directement à l'immunodépression, mais plutôt à l'environnement local particulier induit par la croissance du champignon. Nous avons aussi recherché la prévalence de l'infection à trichomonadine chez les patients atteints d'affection respiratoire grave hospitalisés dans une unité de réanimation polyvalente. Nous avons retrouvé une prévalence de 30% au cours du syndrome de détresse respiratoire aiguë (SDRA). Il est apparu que l'incidence augmente avec la durée d'évolution de l'oedème lésionnel, atteignant 65% au-delà du 5ème jour. Ainsi, cette surinfection se présente comme une évolution naturelle du SDRA (réf 6). La surinfection à trichomonadines apparaît bien dans un second temps, favorisée par les conditions locales à l'intérieur de la lumière alvéolaire (hypoventilation, débris organiques). Ces conditions locales sont aussi présentes au cours de la PcP et doivent être favorables au développement de ce parasite microaérophile. Cette surinfection lors des SDRA renforce l'idée que la trichomonadine manifeste un opportunisme de condition locale, et non de condition générale - telle que l'immunodépression - ainsi que le font la plupart des agents infectieux opportunistes (réf 4 et 5). Dans deux cas, la trichomonadine co-infectant une PcP a pu être identifiée par PCR suivie de séquençage de l' ARNr 16S ou de l'ARNr 5. 8S. Il s'agissait de T. Vaginalis dans le premier cas, et de Tritrichomonas foetus (T. Foetus) dans l'autre cas (réf 1 et 3). Concernant ce second cas, l'origine de cette trichomonadine, qui est connue chez les ruminants, est restée imprécise. Une espèce proche du T. Foetus bovin, mais adaptée à l'homme, n'est pas écartée. L'identification de ces deux espèces va à l'encontre de l'opinion que seul Trichomonas tenax, saprophyte de la cavité buccale, pourrait se développer dans le système respiratoire. T. Vaginalis et T. Foetus ont en commun d'être des pathogènes au niveau des voies génito-urinaires de l'humain et du bovin respectivement. La poursuite (en projet) de l'identification de la trichomonadine co-infectant la PcP ou surinfectant le SDRA pourrait confirmer l'impression que les trichomonadines en cause sont des espèces zoonotiques ou non décrites à ce jour. Le dernier volet a été la recherche d'un système de détection et de typage des trichomonadines dans les échantillons biologiques à l'aide de sondes oligonucléotidiques en hybridation in situ chromogénique (HISC). Différentes sondes, complémentaires de l'ARNr 16S et spécifiques de la classe Trichomonadida ou de ses genres et espèces, ont été testées et ont pu marquer les trichomonadines dans les échantillons cytologiques (réf 6). La transposition aux prélèvements solides, formolés et inclus en paraffine, n'est pas au point à ce jour. Par contre, avec des sondes complémentaires de séquences répétées présentes dans le génome de T. Vaginalis, des marquages ont été obtenus sur coupe en paraffine. Dans l'avenir, la réalisation de marquages en HISC devrait permettre de compléter la liste des conditions où les trichomonadines peuvent être impliquées. L'HISC sur coupe tissulaire devrait par ailleurs permettre de préciser visuellement les rapports entre le parasite et l'environnement, et donc de préjuger l'éventuelle action pathogène du parasite.
2
Malli, Sophia. "Formulations multifonctionnelles pour le traitement des infections parasitaires cutanéo-muqueuses." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS043.
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Ce projet vise à proposer des nouveaux candidats médicaments pour lutter contre les infections parasitaires cutanéo-muqueuses qui représentent un problème de santé majeur. C’est notamment le cas de la Trichomonose urogénitale et la leishmaniose cutanée.Malheureusement, l’administration systémique de première intention par le métronidazole (MTZ) pour traiter la trichomonose urogéntitale occasionne des problèmes de résistances et des effets secondaires indésirables. Ainsi, nous avons développé de nouvelles stratégies thérapeutiques en ciblant à la fois les mécanismes pharmacologiques et physiques de l’infection par Trichomonas vaginalis. Après avoir réussi à augmenter la solubilité apparente du MTZ dans l’eau en utilisant une beta-cyclodextrine méthylée, nous l’avons formulé dans un hydrogel thermosensible et mucoadhésif composé de pluronic® F127 et d’un biopolymère cationique et mucoadhésif, le chitosane. Cette formulation est spécifiquement adaptée à une application topique tout en offrant un contrôle de la libération du MTZ et une réduction de son passage systémique à travers la muqueuse vaginale. La viscosité élevée de l’hydrogel à température corporelle nous a conduit à étudier son effet sur la mobilité du protozoaire Trichomonas vaginalis. Il s’agit d’une stratégie physique d’immobilisation du parasite en parallèle à la chimiothérapie par le MTZ. Le suivi des trajectoires des parasites par vidéo-microscopie a montré la capacité de l’hydrogel seul ou en association avec le chitosane à immobiliser complètement T. vaginalis et à inhiber son attachement à la muqueuse. Ces évaluations ont été réalisées chez la souris. Cependant, le chitosane seul n’a pas permis d’immobilier les parasites et n’a pas montré une activité anti-T. vaginalis propre. Dans ce contexte, nous nous sommes inspirés des travaux antérieurs menés par notre équipe sur le développement de formulations à base de chitosane, et plus particulièrement des nanoparticules (NPs) composées de poly(isobutylcyanoacrylates) recouvertes de chitosane. Ces NPs ont une activité trichomonacide propre, même sans rajouter des substances actives, alors que des NPs sans chitosane étaient inactives. Nous avons étudié le mécanisme d’action et nous avons montré une meilleure internalisation des NPs lorsqu’elles étaient recouvertes de chitosane. Ces NPs ont provoqué des altérations morphologiques drastiques de la membrane du parasite. Cette activité pourrait être due en partie à l’interaction électrostatique entre la surface de T. vaginalis chargée négativement et les NPs recouvertes de chitosane cationique.Dans le but d’élargir le champ des applications de ces NPs à d’autres parasites, nous nous sommes intéressés à l’évaluation de leur effet anti-leishmanien vis-à-vis de Leishmania major. En effet, le chitosane connu pour ces propriétés cicatrisantes nous a paru particulièrement adapté pour cette pathologie. Nous avons ainsi montré in vitro et in vivo que les NPs recouvertes de chitosane avaient une activité anti-L. major propre, sans ajouter de substances actives. Dans un deuxième temps, nous avons décidé de nous orienter vers des particules de formes allongées et d’évaluer leur activité anti-leishmanienne. Ces particules appelées « plaquettes » sont constituées d’assemblages de chitosane hydrophobisé avec l’acide oléique et l’alpha-cyclodextrine dans l’eau. Cette stratégie nous a paru intéressante pour améliorer l’interaction des plaquettes avec la membrane de L. major, vue que ces parasites sont également de morphologie non-sphérique. Les résultats histologiques et immunohistochimiques des lésions cutanées ont montré une diminution significative du granulome inflammatoire et une réduction de la charge parasitaire par rapport à l'amphotéricine B seule utilisée comme référence.En conclusion, au cours de cette thèse, plusieurs formulations ont été développées et ont montré des efficacités biologiques en agissant sur des mécanismes pharmacologiques et/ou physiques des parasites<br>This project aims at developing new therapeutic strategies against parasitic muco-cutaneous infections such as urogenital trichomonosis and cutaneous leishmaniasis which still represents a major health problem worldwide.Unfortunately, metronidazole (MTZ) is a first-line systemic treatment for urogenital trichomoniasis that causes resistance and side effects. We have thus developed new strategies by acting on both the pharmacological and the physical mechanisms of Trichomonas vaginalis infection. After a successfull increase of the apparent solubility of MTZ in water using a methylated -cyclodextrin, we formulated it in a thermosensitive and mucoadhesive hydrogel composed of pluronic® F127 and a cationic and mucoadhesive biopolymer, chitosan. This formulation is specifically adapted for topical application providing a control of MTZ release and reduction of its systemic passage through the vaginal mucosa.Then, the ability of the high viscosity hydrogel to immobilize T. vaginalis was investigated by video-microscopy. Monitoring the trajectories of each parasite by multiple particle tracking showed the ability of the hydrogel alone or in combination with chitosan to completely immobilize T. vaginalis and to inhibit parasite attachment to the mucosa. These evaluations were performed on mice experimental model. However, chitosan alone did not allow parasite immobilization and did not show any anti-T. vaginalis activity. In this context, we were inspired by previous works conducted by our team on the development of formulations based on chitosan, and more particularly nanoparticles (NPs) composed of poly(isobutylcyanoacrylates) coated with chitosan. These NPs have their own trichomonacidal activity, even without adding active substances, while NPs without chitosan were inactive. Investigated of the mechanism of the activity showed better internalization of NPs when coated with chitosan. These NPs caused drastic morphological alterations on the parasite membrane. This activity could be due to the electrostatic interaction between negatively charged T. vaginalis surface and cationic chitosan coated NPs.In order to broaden the applications of these NPs to other parasites, we were interested in evaluating the anti-L. major activity of NPs coated or not with chitosan. Indeed, chitosan known for its healing properties could be particularly adapted for this pathology. We thus showed in vitro and in vivo that NPs coated with chitosan had intrinsic anti-L. major activity without adding any drug. In a second step, we decided to design chitosan elongated particles and to evaluate their anti-leishmanial activity. These particles called "platelets" are composed of chitosan hydrophobically-modified with oleic acid and cyclodextrin in water. This strategy could be interesting to improve the interaction of platelets with the L. major membrane, as these parasites had also non-spherical morphology. The histological and immunohistochemical results of skin lesions showed a significant decrease in inflammatory granuloma and a reduction in parasitic load compared with amphotericin B alone, used as a reference.In conclusion, during this thesis, several formulations were developed and showed biological activities by acting on pharmacological and/or physical mechanisms of the parasites
3
Chapman, A. "Biochemistry of Trichomonas vaginalis." Thesis, Bucks New University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373578.
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Zuo, Yuting. "Trichomonas vaginalis cell cycle studies /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/9301.
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Patel, Nimisha Navinchandra. "Expression and analysis of a legumain from trichomonas vaginalis." Scholarly Commons, 2009. https://scholarlycommons.pacific.edu/uop_etds/733.
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Trichomonas vaginalis and Tritrichomonas foetus are the etiologic agents of human and bovine trichomoniasis, respectively. As microaerophilic protozoans; both share a wide array of clinical manifestations ranging from vaginitis to abnormal pregnancies. Human trichomoniasis receives minimal public health attention despite of its worldwide high prevalence rate. Emerging evidence of metronidazole-resistant T vaginalis strains facilitates a concern to understand this protozoan. Cysteine proteases have been implicated as important virulence factors produced by T vagina/is. This study explores the expression of one particular legumain-like cysteine protease known as Tv AE 1. Furthermore, it highlights the relationship between inhibitory effects of trichomonal cells caused by sanguinarine and chelerythrine. A system for obtaining legumains by expressing it in methylotrophic yeast, Pichia pastor is, has been described. The recombinant legumains were produced and processed by the yeast to their inactive and mature forms. Secondly, T foetus cells were transfected with TvAEl construct.
Localization and enzymatic studies on legumains will provide evidence into the pathogenicity ofT vagina/is. This study revealed the vesicularization of recombinantly unprocessed TvAEl proteins. Thirdly, plant derived compounds, sanguinarine (SA) and chelerythrine (CHE) were assessed in vitro for their inhibitory effects against T vagina/is and T. foetus. Treatment of SA and CHE for 24 h led to a significant inhibitory growth of in vitro cultures for all three trichomonal strains, G3, Tl and Dl, compared to untreated cells. For these bovine and human trichomonal strains, SA was slightly more effective inhibitor than CHE. With IC5o values between 3 - 8 micromolar for the alkaloids, CHE had less inhibitory effect compared to SA. These findings are significant considering the association between cysteine pro teases and trichomoniasis. Further elucidation of the exact anti protozoal mechanism of both compounds toward legumains may lead to the development of these potent agents against trichomonads.
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Bradley, Peter John. "Hydrogenosomal protein import in Trichomonas vaginalis." Diss., Restricted to subscribing institutions, 1997. http://proquest.umi.com/pqdweb?did=736748871&sid=10&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Jauregui, Jose. "Auranofin Targets Thioredoxin Reductases in Trichomonas vaginalis." Scholarly Commons, 2017. https://scholarlycommons.pacific.edu/uop_etds/2976.
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Trichomonas vaginalis is an anaerobic, parasitic protozoan, responsible for trichomoniasis, the world’s most common, non-viral sexually transmitted infection. Lacking many of the defenses present in other organisms to combat oxidative stress, Trichomonas vaginalis relies extensively on the thioredoxin system—NADPH, thioredoxin reductase, and thioredoxin—as a means to protect against exposure to excess oxygen. Current trichomoniasis treatment relies exclusively on the 5-nitroimidazole drugs, but fear of drug-resistant strains and allergic reactions to 5-nitroimidazole treatment necessitate the discovery of a new treatment method for trichomoniasis. Previous research has shown that auranofin, an FDA-approved drug, was effective at inhibiting activity of one of Trichomonas vaginalis’ isoforms of thioredoxin reductase (of which the organism has five total). Our research showed that only two of the isoforms were transcribed and expressed at high levels, and that both of these isoforms were susceptible to auranofin treatment. Not only that, these two isoforms were also shown to be susceptible to various auranofin analogs, having comparable or lower IC50 values. Further tests on these analogs might show that they are actually better treatment candidates if they exhibit less symptoms than auranofin. Experiments examining how mRNA and protein levels were modulated in response to two different concentrations of auranofin treatment showed that while some isoforms show increased levels, no one isoform experienced any drastic changes. Together, this data suggests that further studies should focus on these two most highly expressed isoforms of thioredoxin reductase.
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Petrin, Dino P. "Molecular and biochemical studies of Trichomonas vaginalis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0011/MQ28454.pdf.
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Acquistapace, Bethany R. "Analysis of a trichomonas vaginalis cysteine protease." Scholarly Commons, 2007. https://scholarlycommons.pacific.edu/uop_etds/669.
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Trichomoniasis affects 170 million people worldwide, and 7.4 million in the USA. There is increasing focus on the role of cysteine proteases in Trichomonas vaginalis because of their role in virulence of other parasitic protozoa. Determining their location and function will provide insight about their role in the pathogenicity of T. vaginalis and their feasibility as a drug target. This study begins to characterize the first sequenced cysteine protease (CP1). E. coli and P. pastoris expression systems were developed to produce CP1 to generate antiserum, and to have enough active protein for biochemical characterization. Secondly, endogenous and epitope tagged CP1 were localized in T. vaginalis vesicles. These vesicles were confirmed to have alkaline phosphatase activity which is a characteristic of lysosomes. Lastly, deletion mutants of CP1 were created to determine the role of the prodomain in targeting CP1 to vesicles.
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Lockwood, B. C. "Proteinases in trichomonads and trichomoniasis." Thesis, University of Stirling, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377537.
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Santos, Alene Vanessa Azevedo dos. "Reações de oxido redução como alvo na quimioterapia triconomicida." Centro de Pesquisas Gonçalo Moniz, 2008. https://www.arca.fiocruz.br/handle/icict/8879.
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Previous issue date: 2008<br>Fundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Salvador, BA, Brasil<br>Trichomonas vaginalis e Tritrichomonas foetus são os agentes etiológicos da tricomoníase humana e bovina, respectivamente. A primeira é uma parasitose de grande importância em saúde pública, sendo a principal doença sexualmente transmissível não viral e a segunda ocasiona extensos prejuízos econômicos na pecuária. A tricomoníase humana pode promover a incidência de câncer de colo de útero e a transmissão do HIV. Na infestação humana a droga de escolha é o metronidazol, mas não há um composto eficiente para o tratamento de bovinos. Como este fármaco é usado para outras parasitoses e infecções bacterianas desde a década de 60, tem sido documentado o surgimento de casos refratários e cepas resistentes. Além disso, o fármaco pode ter efeitos mutagênicos e carcinogênicos. Assim sendo a busca por novos compostos tricomonicidas constitui uma demanda premente. No presente estudo foram avaliados os efeitos do dietilditiocarbamato de sódio (DETC) sobre os protozoários parasitas T. vaginalis e T. foetus. Observamos que a adição de DETC inibiu significativamente a proliferação de T. vaginalis, produzindo uma IC50 de 269,7nM, enquanto o metronidazol teve uma IC50 de 523,1nM. Em T. foetus os valores de IC50 foram semelhantes, sendo 497,8 e 459,7nM para o DETC e para o metronidazol, respectivamente. Estes compostos não afetaram significativamente a incorporação de [3H]timidina por esplenócitos murinos em concentrações de até 1000M. A atividade mitocondrial de macrófagos peritoneais murinos também não foi afetada por DETC, mesmo em 200μM, sugerindo seletividade no modo de ação. Objetivando determinar a existência de sinergismo entre DETC e metronidazol, foram determinados os valores de FIC (concentração inibitória fracionada) para os dois protozoários. Os valores de FIC foram 0,3 e 0,7 para T. vaginalis e T. foetus, respectivamente. Esta observação indica que ocorre a interação sinergística no protozoário parasita de humanos. A fim de determinar se a incubação com DETC poderia afetar a expressão de grupos sulfidrila dos parasitos empregamos a reação de Ellman para dosar os grupamentos tiol totais de T. vaginalis antes e após a adição do composto. Observamos que o tratamento com DETC por 24h significativamente (p<0,01) reduziu a concentração de grupos tióis do parasito. A detecção de tióis livres pela sonda fluorescente orto-phthalaldeído (OPA) em T. foetus sugere a participação de sulfidrilas no mecanismo de ação do DETC, uma vez que este reduz marcadamente a marcação dos parasitos pelo OPA, mas este efeito foi revertido pela pré-incubação com cisteína. Vale salientar que o aminoácido reverte, ainda, os efeitos do composto na proliferação parasitária. A mensuração de radicais livres por quimioluminescência amplificada pelo luminol indicou que a geração de espécies reativas de oxigênio foi significativamente (p <0,05) aumentada por DETC em T. vaginalis, mas não em T. foetus. O estresse oxidativo sobre os parasitas foi avaliado pela medida de substâncias reativas ao ácido tiobarbitúrico (TBARs). Observou-se que a combinação metronidazol-DETC significativamente aumenta a peroxidação lipídica em T. vaginalis (p <0,01) e T. foetus (p <0,05). A análise ultraestrutural por microscopia eletrônica de transmissão revelou que tanto DETC quanto o metronidazol produziram danos hidrogenossomais e desencadearam autofagia e esses efeitos foram mais acentuadas no parasitas incubados com a combinação de drogas. Tomados em conjunto, estes dados sugerem que a combinação metronidazol-DETC pode fornecer novas ferramentas para a efetiva quimioterapia da tricomoníase<br>Trichomonas vaginalis e Tritrichomonas foetus are the etiologic agents of the human and bovine trichomoniasis, respectively. The former is a parasitic disease of great relevance in public health – the major non-viral sexually-transmitted disease, whereas the latter causes remarkable losses in livestock productivity. Human trichomoniasis can promote the incidence of cervical cancer and HIV transmission. In human infestation the drug of choice is metronidazole, but there is no efficient compound for treating the cattle. Since the medication is also used for other parasitic and bacterial diseases, since the 60s, refractory cases and resistant strains have been documented. Besides, the drug may be mutagenic and carcinogenic. Therefore the search for new trichomonicidal compounds is required. In the present study we investigated the effects of sodium N,N-diethylthiolcarbamate (DETC) alone or combined with metronidazole upon the parasitic protozoa T. vaginalis and T. foetus. We notice that DETC significantly inhibited the T. vaginalis proliferation, producing an IC50 of 269.7nM, whereas metronidazole produced an IC50 of 523.1. In T. foetus the IC50 values were similar, being 497.8 and 459.7nM for DETC and metronidazole, respectively. These compounds did not significantly affect the incorporação de [3H]timidine incorporation by murine splenocytes in concentrations up to 1000μM. The mitochondrial activity of murine peritoneal macrophages was not affected by 200μM DETC, suggesting a selective mode of action. In order to determine whether there is synergism between DETC and metronidazole, we determined the fractional inhibitory concentrations (FIC) of these compounds upon both protozoa. The FIC values for T.vaginalis and T. foetus were 0.3 and 0.7, respectively. This observation indicates that synergistic interaction takes place only on the human pathogen. To determine whether the incubation with DETC could affect the expression of sulphydril groups of parasites we employed the Ellman’s reaction to measure the total thiol groups of T. vaginalis before and after the addition of the compound. We observed that treatment with DETC for 24h significantly (p <0.01) reduced the concentration of thiol groups of the parasite. The detection of free thiols by the fluorescent probe ortho- phthaldialdehyde (OPA) in T. foetus suggests the involvement of sulphydrils in the DETC mechanism of action, since it markedly reduces the OPA labeling of parasites, but this effect was reversed by cysteine preincubation with. It is noteworthy that the amino acid addition also reverts, the effects of the compound on the parasite proliferation. The measurement of free radicals by luminol-enhanced chemiluminescence indicated that reactive oxygen species generation was significantly (p <0.05) enhanced by DETC in T. vaginalis, but not T. foetus. The oxidative stress on the parasites was evaluated by measurement of the thiobarbituric acid-reactive substances (TBARs). We observed that the metronidazole-DETC combination significantly enhanced lipid peroxidation in T. vaginalis (p <0.01) and T. foetus (p <0.05). The ultrastructural analysis by transmission electron microscopy revealed that both DETC and metronidazole produced hydrogenosomal damage and triggered autophagy and these effects were more pronounced on the parasites incubated with the combined drugs. Taken together these data suggest that the metronidazole-DETC combination may furnish new tools in the effective chemotherapy of trichomoniasis.
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N'Diaye, Ibrahima. "Annelation du benzimidazole : étude chimique et parasitologique des dérivés tricycliques et de leurs précurseurs." Paris 11, 1986. http://www.theses.fr/1986PA112140.
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Ce travail a été réalisé dans le but d'obtenir des dérivés tricycliques du benzimidazole susceptibles d'avoir une activité antiparasitaire. L'étude chimique est présentée en quatre chapitres. Le premier consiste en la synthèse de chloro-2 benzimidazoles substitués en 1 par une chaîne fonctionnalisée. Les homologues nitrés au noyau benzénique ont également été préparés en raison du caractère pharmacophore antiparasitaire de ce substituant. Les autres chapitres portent sur les réactions des nucléophiles azotés ou oxygénés avec les chloro-2 benzimidazoles substitués en 1. Des benzimidazoles substitués non encore décrits ainsi qu'un nouveau squelette tricyclique (dihydro-1,2 triazino-1,2,4 [4,3-a] benzimidazole) ont été obtenus. De nouvelles voies d'accès au dihydro-1,4 triazino-1,2,4 [4, 3-a] et au dihydro-2,3 oxazolo [3,2-a] benzimidazole ont été étudiées. Les structures des produits ont été établies par l'analyse spectrale (I. R. , RMN et masse) et les mécanismes des réactions discutés. L'étude pharmacologique a porté sur les principaux types de composés préparés dans ce travail. Ceux-ci ont été évalués sur quatre espèces de parasites : deux protozoaires, Entamoeba histolytica et Trichomonas vaginalis et deux helminthes, Hymenolepis nana et Nippostrongylus brasiliensis. Certains dérivés présentent une activité intéressante vis-à-vis du Trichomonas vaginalis<br>The aim of this work is to obtain tricyclic derivatives of benzimidazole with potential antiparasitic activity. Chemical studies were presented in four chapters. The first chapter contains the synthesis of activated N-substituted 2-chlorobenzimidazoles. Homologous nitro derivatives have also been prepared in order to study the influence of the nitro group as an antiparasitic pharmacophore. The other chapters concern the reactions of oxygen and nitrogen nucleophiles with N-substituted 2-chlorobenzimidazoles. New benzimidazole derivatives and a new tricyclic skeleton related to benzimidazole (1,2-dihydro 1,2,4-triazino [4,3-a] benzimidazole)have been prepared. An original approach for the synthesis of 1,4-dihydro 1,2,4-triazino [4,3-a] and 2,3-dihydrooxazolo [3,2-a] benzimidazoles has also been studied. The structures of the compounds were elucidated by spectroscopic studies (I. R. , NMR and mass spectrography) and the mechanisms of reactions were discussed. Most of the prepared compounds were tested on four different parasites: two protozoa, Entamoeba histolytica and Trichomonas vaginalis and two helminths, Hymenolepis nana and Nippostrongylus brasiliensis. Interesting activities were found in the case of certain derivatives, especially against Trichomonas vaginalis
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LEMOS, Patrícia Abreu Pinheiro de. "Ocorrência da infecção por Trichomonas vaginalis em mulheres HIV positivas e negativas atendidas em hospitais de referência em Goiânia, Goiás, Brasil." Universidade Federal de Goiás, 2008. http://repositorio.bc.ufg.br/tede/handle/tde/1798.
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Previous issue date: 2008-12-17<br>This study evaluated the frequency of Trichomonas vaginalis infection in
human immunodeficiency virus positive (HIV+) and negative (HIV-) women in
Goiania, Goiás, Brazil, comparing the presence of the parasite in the two groups and
correlating it with the conditions of immunodeficiency present in these women. The
diagnostic techniques used, wet mount microscopy, culture and cytology, were also
evaluated, and the principal inflammatory alterations in the two groups were
assessed. The HIV+ samples (test group) were collected at the Hospital of Tropical
Diseases and in the Maternal and Child Healthcare Hospital, whereas the HIVnegative
samples (control group) were collected at the Maternity Hospital. Swabs
were used for wet mount microscopy (saline solution) and for culture (Diamond s
medium), and Ayre s spatula and brush were used for the cytology smears, which
were fixed using a commercial fixative. A total of 237 samples were analyzed, 125
HIV-positive test samples and 112 HIV-negative controls. The overall frequency of T.
vaginalis was 13.9%, 18.4% in the HIV+ and 8.9% in the HIV- group. This difference
was statistically significant (p<0.05); however, the infection was not associated with
immunodeficiency according to CD4, viral count and lymphocytes. There was a
significant difference in the prevalence of the parasite between HIV+ and HIVpregnant
women (22.6% versus 12.5%). Culture identified a frequency of T.
vaginalis of 13.9%, while cytology identified a rate of 13.5% and wet mount
microscopy 11.4%. Perinuclear halos were the most frequent inflammatory
alteration; however, there was no difference between the groups<br>O estudo avaliou a freqüência da infecção por Trichomonas vaginalis em
mulheres HIV+ (vírus imunodeficiência humana) e HIV- em Goiânia-GO,
comparando a presença do parasito e correlacionando com as condições de
imunodeficiência. Avaliou também as técnicas de diagnóstico: exame a fresco, cultura
e citologia, e apontou as principais alterações inflamatórias nos dois grupos. As
amostras de HIV+ (grupo teste) foram coletadas no Hospital de Doenças Tropicais e
no Hospital Materno Infantil e as de HIV negativas (grupo controle) na Maternidade
Nascer Cidadão. Foram utilizados swabs para os exames a fresco (salina) e para a
cultura (meio Diamond), espátula de Ayre e escovinha para os esfregaços citológicos
que foram submetidos a fixadores comerciais. Foram examinadas 237 amostras: 125
do teste e 112 do controle. A freqüência por T. vaginalis foi 13,9%, sendo 18,4% nas
HIV+ e 8,9% nas HIV-. O resultado foi estatisticamente significativo (p<0,05), porém
a infecção não foi associada à imunodeficiência (CD4, carga viral e linfócitos). Houve
diferença significativa entre grávidas HIV+ e HIV- (22,6% vs 12,5%). A Cultura
obteve 13,9% da presença de T.vaginalis, a Citologia 13,5% e o exame a fresco 11,4%.
Halos perinucleares predominaram na avaliação das alterações inflamatórias, porém
não houve diferença entre os grupos.
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Williams, K. P. "Studies on pyruvate : ferredoxin oxidoreductase from Trichomonas vaginalis." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234978.
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In the anaerobic protozoon <i>Trichomonas vaginalis</i>, the oxidative decarboxylation of pyruvate is catalysed in a CoA-dependent reaction by pyruvate: ferredoxin oxidoreductase (PFOR). This enzyme has been identified as a potential target for the development of a relatively non-toxic anti-trichomonal agent. 1. <i>T. vaginalis</i> PFOR was localised in the hydrogenosomal membrane fraction, and could be solubilised by buffer of high ionic strength. A high salt concentration was required to prevent aggregation of PFOR. These results suggested that PFOR was either an extrinsic protein bound to the hydrogenosomal membrane or that the enzyme exists <i>in vivo</i> in the hydrogenosomal matrix in an aggregated state. PFOR was solubilised and purified to homogeneity, the most _ffective step being salting-out chromatography on Sepharose 4B. Low recoveries of active enzyme were caused by inactivation by oxygen and the irreversible loss of thiamin pyrophosphate (TPP). 2. PFOR is a dimeric enzyme of overall M<SUB>r</SUB>240000. The enzyme contains 0.5 mol of TPP per mol of dimer, and equivalent amounts of non-haem iron and acid-labile sulphur, consistent with the presence of two [4Fe-4S] centres per enzyme molecule. Flavin nucleotides and lipoic acid are absent. PFOR from <i>T. vaginalis</i> is therefore broadly similar to the 2-oxo acid:ferredoxin (flavodoxin) oxidoreductases purified from bacterial sources, and clearly different from the 2-oxo acid dehydrogenase multienzyme complexes which occur in aerobic organisms. 3. A steady-state kinetic analysis of purified PFOR demonstrated that the enzyme obeyed Bi Bi Ping Pong kinetics except at very high CoA concentrations, where substrate inhibition occurred. The inhibition produced by the product of acetyl-CoA, in the presence of saturating CoA, was competitive with respect to pyruvate. In the absence of CoA, stoichiometric amounts of pyruvate were decarboxylated by PFOR. These results suggest that decarboxylation, formation of the stable imtermediate and its reaction with CoA to form acetyl-CoA all take place at one active site. 4. Spectroscopic investigations using electron paramagnetic resonance indicated that the stable intermediate formed after pyruvate decarboxylation was a free-radical species. This substrate-based radical is proposed to arise by the transfer of a single electron from the initial decarboxylation product to a [4Fe-4S] centre. The free-radical signal was greatly diminished if the enzyme was subsequently incubated with CoA, suggesting that it represents a real catalytic intermediate. 5. <i>T. vaginalis</i> PFOR was inactivated by incubation with pyruvate alone, a reaction the enzyme has in common with the <i>E. coli</i> pyruvate dehydrogenase (PDH) complex and yeast pyruvate decarboxylase, suggesting similarities between these enzymes at least in the initial formation of the decarboxylated intermediate, presumed to be the enamine of hydroxyethyl-TPP. The conjugated 2-oxo acid, (E)-4-(-chorophenyl)-2-oxo-3-butenoic acid, was an irreversible inhibitor of <i>T. vaginalis</i> PFOR and yeast pyruvate decarboxylase, a result taken to reflect the initial formation of an enamine intermediate in each case. 6. 3-hydroxypyruvate was a potent irreversible inhibitor of <i>T. vaginalis</i> PFOR. The observation that 3-hydroxypyruvate was also an alternative substrate for pyruvate in the overall reaction suggested that it might be acting as a mechanism-based inactivator. 3-hydroxypyruvate was ineffective against <i>E. coli</i> PDH complex suggesting an interesting difference in active site geometry that might be exploited for potential drug design.
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Trein, Marcia Rodrigues. "Síntese e atividade anti-Trichomonas vaginalis de chalconas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/164467.
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Tricomoníase é a doença sexualmente transmissível não-viral mais comum no mundo e pode gerar sérias consequências na saúde reprodutiva, câncer e transmissão e aquisição do HIV. Por esta razão, esta infecção resulta em um pesado fardo para os sistemas de saúde pública. O único tratamento aprovado para esta infecção, que consiste nos 5-nitromidazois metronidazol e tinidazol, apresenta efeitos adversos e há uma subestimada taxa de resistência da infecção, atualmente considerada uma doença negligenciada, a estes fármacos. Portanto, há uma necessidade urgente de novas alternativas terapêuticas para a tricomoníase. Chalconas são uma família de moléculas que apresenta várias aplicações biológicas, como atividade contra diversos patógenos, incluindo protozoários patogênicos. Este trabalho apresenta o potencial anti-Trichomonas vaginalis de derivados de chalcona sintetizados e seus efeitos sobre os trofozoítos. Os valores de IC50 dos compostos mais ativos variaram de 27,5 a 76,4 μM, e as moléculas 4’-hidroxichalcona e 3’-aminochalcona apresentaram os valores mais baixos (27,5 e 28,9 μM). Estes dois compostos foram citotóxicos contra a linhagem de células epiteliais vaginais HMVII, consequentemente apresentaram baixos Índices de Seletividade; contudo, ao se utilizar larvas de Galleria mellonella, como modelo de toxicidade in vivo, não foi observada diminuição da viabilidade após o tratamento. As moléculas também não provocaram hemólise em eritrócitos humanos em 1 e 24 horas. Os compostos não induziram significativa produção de espécies reativas de oxigênio (EROs) nos trofozoítos. Neutrófilos humanos apresentaram aumento na produção de EROs quando coincubados com trofozoítos tratados com os compostos. Os resultados indicam que as chalconas são uma família de moléculas com potencial atividade contra T. vaginalis.<br>Trichomoniasis is the most common non-viral sexually transmitted disease worldwide and can lead to serious consequences in reproductive health, cancer and HIV acquisition. For this reason, this infection results in a heavy burden for public health systems. Current approved treatment, which consists in 5-nitromidazole drugs, metronidazole and tinidazole, present adverse effects and there is underestimate drug resistance data on this parasitic infection, currently considered a neglected disease. Therefore, there is an urgent need for new alternatives for trichomoniasis treatment. Chalcones are a family of molecules that present various biological applications, such as activity against many pathogenic organisms including protozoan pathogens. This study presents the anti-Trichomonas vaginalis potential of synthetized chalcone derivatives and their effects on the trophozoites. IC50 values of the most active compounds ranged from 27.5 to 76.4 μM, and 4’-hydroxychalcone and 3’- aminochalcone presented the lowest values of IC50 (27.5 and 28.9 μM). These two compounds showed cytotoxicity against HMVII vaginal epithelial cells, thus presenting a low Selectivyty Index; however, when Galleria mellonella larvae were used as model for in vivo toxicity no significant decrease in viability after treatment was observed. The chalcones also did not induce hemolysis in human erythrocytes The compounds did not induce significant reactive oxygen species (ROS) production in the trophozoites. Human neutrophils have increased ROS production when exposed to treated trophozoites. Results indicate that chalcones are a family of molecules with potential activity against T. vaginalis.
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Senger, Franciane Rios. "Micro-organismos marinhos como fonte de metabólitos bioativos: atividade anti-trichomonas vaginalis, antibiofilme e antibaceriana." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/148116.
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Nos últimos anos, os metabólitos isolados de fungos marinhos vêm ganhando considerável atenção em razão de possuírem estruturas químicas únicas com diversas atividades biológicas já descritas, incentivando novas pesquisas na área. A tricomoníase é a doença sexualmente transmissível (DST) de origem não viral mais comum no mundo, estando associada a sérias consequências à saúde, sendo relatado um aumento no número de isolados clínicos resistentes ao tratamento de escolha. Infecções causadas por bactérias com diferentes mecanismos de resistência, representam um grande desafio para a saúde pública atual, acarretando em altas taxas de mortalidade e morbidade. As bactérias patogênicas dispõem de fatores de virulência, como a formação de biofilme, que agravam infecções tornando-as persistentes. Devido ao potencial biológico dos produtos de origem marinha e a importância dessas infecções, o objetivo deste estudo foi avaliar a atividade anti-T. vaginalis, antimicrobiana e antibiofilme de moléculas obtidas da fermentação de fungos associados a organismos marinhos. As 14 cepas fúngicas foram isoladas de esponjas e corais marinhos, obtidos da costa do estado de Alagoas, Brasil. Após produção do metabólito, o micélio foi separado do meio. O micélio foi extraído com metanol e o meio com acetato de etila. As frações foram submetidas aos ensaios de atividade anti-T.vaginalis, antimicrobiana e antibiofilme (inibição da formação e erradicação). As frações que demonstraram atividade foram submetidas ao ensaio de hemólise, avaliação da citotoxicidade (HMVII e Vero) e toxicidade em modelo de Galleria mellonella. A fração que demonstrou os melhores resultados nos ensaios de atividade foi submetida ao fracionamento bioguiado. As frações orgânicas dos fungos Aspergillus niger (FMPV 03) e complexo Trichoderma harzianum/Hypocrea lixii (FMPV 09) foram ativas frente ao T. vaginalis ATCC 30236, com valores de MIC de 2 mg/mL e 1 mg/mL, respectivamente. Quando investigadas, essas frações mantiveram a atividade frente ao isolado clínico resistente ao metronidazol (TV-LACM2R), apresentado os mesmo valores de MIC encontrados para o isolado ATCC. Para a atividade antimicrobiana, as frações orgânicas do Aspergillus niger (FMPV 03), Aspergillus tubingensis (FMPV 06), complexo Trichoderma harzianu/Hypocrea lixii (FMPV 09) e Aspergillus sydowii (FMPV 10) foram ativas contra S. epidermidis ATCC 35984. Ainda, frente a P. aeruginosa ATCC 27853 somente as frações orgânicas do Aspergillus niger (FMPV 03) e Aspergillus tubingensis (FMPV 06) demonstraram atividade. Neste ensaio, para ambas as bactérias, os valores de MIC não ultrapassaram 1,5 mg/mL. A atividade destas frações também foi observada frente às mesmas bactérias no ensaio de antiformação de biofilme, já que ocorreu a morte das células. A habilidade de erradicar biofilmes foi detectada somente para a fração orgânica do fungo Aspergillus flavus (FMPV 01), o qual foi capaz de remover 52% do biofilme já formado de S. epidermidis ATCC 35984. A ausência de hemólise dos eritrócitos foi observada em todas as frações ativas estudadas. Na avaliação da citotoxicidade in vitro frente às linhagens celulares HMVII e Vero, apenas a fração orgânica do Aspergillus niger (FMPV 03), não apresentou efeito citotóxico. No entanto, no ensaio de avaliação da toxicidade in vivo, nenhuma das amostras testadas causou redução na sobrevivência das larvas de Galleria mellonella. Então, a fração orgânica do fungo Aspergillus niger (FMPV 03) foi submetida ao fracionamento bioguiado utilizando coluna RP-18. Sete frações foram obtidas, sendo que a primeira (100% água), foi ativa contra T. vaginalis, S. epidermidis e P. aeruginosa. Quando submetida à Cromatografia em Camada Delgada (CCD), demonstrou quatro bandas que foram coradas com anisaldeído-ácido sulfúrico e ninhidrina. Além disso, a fração 100% água não demonstrou redução da sobrevivência das larvas de Galleria mellonella, nas três concentrações testadas. Portanto, a gama de atividades relatadas corrobora o potencial dos fungos marinhos na produção de moléculas bioativas.<br>In recent years, the isolated metabolites from marine fungi have been attracted considerable attention due to unique chemical structures with diverse biological activities, encouraging further research in the area. Trichomoniasis is the most prevalent non-viral sexually transmitted disease (STD) worldwide. This has been linked to serious health consequences and an increase in the number of clinical isolates resistant to the treatment of choice has been reported. Infections caused by bacteria with different resistance mechanisms represent a major challenge to the current public health, resulting in high rates of mortality and morbidity. Pathogenic bacteria present virulence factors, such as biofilm formation, which migth enhance the persistence of infections. Due to the biological potential of marine products and the importance of these infections, the aim of this study was to evaluate the anti-T. vaginalis, antimicrobial and antibiofilm activities of the obtained molecule from the fermentation of fungi associated with marine organism. The 14 fungal strains were isolated from sponges and corals marine obtained from the coast of Alagoas, Brazil. After production of the metabolite the mycelium was separated from the medium. The mycelium was extracted with methanol and the medium with ethyl acetate. The fractions were subjected to the assays anti-T. vaginalis, antimicrobial and antibiofilm (inhibition of the formation and eradication) activities. The fractions that showed activity were subjected to the assays of hemolysis, cytotoxicity evaluation (HMVII and Vero) and toxicity Galleria mellonella model. The fraction which showed the best results in activity assays was subjected to fractionation bioguided. The organic fraction of Aspergillus niger (FMPV 03) and Trichoderma harzianum/Hypocrea lixii complex (FMPV 09) were active against T. vaginalis ATCC 30236 with MIC values of 2 mg/mL and 1 mg/mL, respectively. When investigated, these fractions maintained activity against resistant clinical isolate to metronidazole (TV-LACM2R), presented the same MIC values found to isolate ATCC. For the antimicrobial activity, the organic fractions of Aspergillus niger (FMPV 03), Aspergillus tubingensis (FMPV 06), Trichoderma harzianum/Hypocrea lixii complex (FMPV 09) and Aspergillus sydowii (FMPV 10) were active against S. epidermidis ATCC 35984. Even, against P. aeruginosa ATCC 27853 only the organic fractions of Aspergillus niger (FMPV 03) and Aspergillus tubingensis (FMPV 06) demonstrated activity. In this test, for both bacteria, MIC values did not exceed 1.5 mg/mL. The activity of these fractions was also observed across the same bacteria in the antibiofilm formation assay, since cell death occurred. The ability to eradicate biofilms was detected only for the organic fraction of the fungus Aspergillus flavus (FMPV 01) which was able to remove 52% of the already formed biofilm of S. epidermidis ATCC 35984. The absence of hemolysis of red cells was observed in all active fractions studied. In the assessment of cytotoxicity in vitro against the cell lines HMVII and Vero, only the organic fraction of Aspergillus niger (FMPV 03), showed no cytotoxic effect. However, in the test evaluation of in vivo toxicity, none of the samples tested caused a reduction in the survival of the larvae of Galleria mellonella. Then, the organic fraction of the fungus Aspergillus niger (FMPV 03) was submitted to bioguided fractionation using RP-18 column. Seven fractions were obtained, of which the first (100% water), was active against T. vaginalis, S. epidermidis e P. aruginosa. When subjected to thin layer chromatography (TLC) showed four bands were stained with ninhydrin and anisaldehyde-sulfuric acid. In addition, 100% water fraction showed no reduction of the survival of larvae of Galleria mellonella at the three concentrations tested. Therefore, the range of activities reported corroborates the potential of marine fungi to produce bioactive molecules.
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Giordani, Raquel Brandt. "Atividade anti-trichomonas vaginalis de alcaloides de amaryllidaceae e análogos de poliaminas : análise química, semi-síntese e investigação do mecanismo de ação." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/26891.
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A família Amaryllidaceae é reconhecida como fonte de compostos bioativos, sendo o isolamento e elucidação estrutural de seus alcaloides, aliado às avaliações farmacológicas, um tema importante. Estudos mostram que o mecanismo de ação da citotoxicidade desses alcaloides é seletivo e depende da linhagem celular. Trichomonas vaginalis é um protozoário parasita que causa a tricomonose, a doença sexualmente transmissível de origem não viral mais comum no mundo. Além de ser considerado um importante organismo patogênico, suas características bioquímicas peculiares, como a ausência de mitocôndrias, torna o tricomonas um adequado modelo para estudos de vias metabólicas de morte celular. A atividade anti-T. vaginalis dos alcaloides de Amaryllidaceae licorina e candimina, assim como o potencial citotóxico de diaminas sintéticas, foram investigados. Estudos de semi-síntese com a licorina também foram desenvolvidos. Nossos resultados mostraram que a licorina e candimina induzem importantes alterações na ultraestrutura dos parasitos e nenhum marcador morfológico clássico de apoptose, como corpos apoptóticos, foi observado. Além disso, nem a fragmentação do DNA genômico nem a exposição de resíduos de fosfatidilserina foram detectadas. Por outro lado, ambos os alcaloides atrasaram o ciclo celular do parasito e inibiram a atividade das enzimas NTPDase e ecto-5`- nucleotidase, importantes na manutenção da relação parasito/hospedeiro. O alcaloide pró-apoptótico licorina e a candimina induziram morte celular no parasito amitocondriado T. vaginalis por um mecanismo de ação que não cumpre as características morfológicas de apoptose. Entretanto, similaridades com a morte celular denominada paraptose foram observadas: intensa vacuolização citoplasmática periférica aliada à integridade nuclear. Considerando que a citotoxicidade dos alcaloides pode ser considerada moderada (250 μM), derivados de poliaminas foram escolhidos para desenvolver estudos de semi-síntese com a licorina e aperfeiçoar a atividade do alcalóide. Poliaminas são moléculas catiônicas de estruturas simples, essenciais para a diferenciação celular e regulação do ciclo celular. Neste trabalho demonstrou-se a síntese e avaliação da atividade anti-T. vaginalis de uma série de derivados de diaminas, dos quais N-hexadecil-1,4-butanodiamina apresentou CIM igual a 2,5 μg/ml, duas vezes mais ativo em comparação ao metronidazol, utilizado como composto de referência. A hibridização molecular da licorina com as diaminas foi prejudicada pela instabilidade da licorina mesilada, intermediário chave para prosseguir a rota sintética. No entanto, seis derivados inéditos da licorina, todos ésteres, aromáticos ou alifáticos, foram sintetizados.<br>Amaryllidaceae family has proven to be plentiful sources for therapeutic agents. Hence, the isolation, biology and chemistry of the Amaryllidaceae alkaloids make an important subject. Investigations on cytotoxic mechanisms of these alkaloids indicate a promising selective cell-type-dependent cytotoxicity. Trichomonas vaginalis is a parasite that causes trichomonosis, the number one non-viral sexually-transmitted disease in the world. However, whilst T. vaginalis is a prime pathogenic target, its lack of mitochondria makes it a suitable biochemical model to study cell death-related mechanisms. Anti-T. vaginalis activity of lycorine and candimine alkaloids were investigated, as well as the cytotoxic potential of diamine analogs. Finally, studies on lycorine semi-synthesis were developed. Our results showed that, after lycorine and candimine treatment, no hallmark suggestive of apoptosis were observed, such as apoptotic bodies, but instead several important ultrastructural alterations, assessed by electronic microscopy. Additionally, DNA fragmentation and membrane phosphatidylserine exposure were not detected. Analysis showed that lycorine and candimine arrested T. vaginalis cell cycle and inhibited the NTPDase and ecto-5`- nucleotidase activities, important enzymes on parasite/host relationship. The proapoptotic alkaloid, lycorine, and the lactone alkaloid, candimine, caused cell death in the amitochondriate T. vaginalis by a mechanism of action that fails to completely fulfill the criteria for apoptosis. However, some similarities were observed to paraptotic cell death, like intense cytoplasmic periferic vacuolization and nuclear integrity. Since the cytotoxic potential of the alkaloids was moderated (250 μM), the polyamines analogs were chosen to investigate the anti-T. vaginalis activity and to develop semi-synthesis studies with lycorine in order to improve the alkaloid cytotoxicity. Polyamines are simple structured aliphatic amines essential for cell proliferation and differentiation and it has been shown that interfering with their function or biosynthesis the cellular growth can be blocked. Our results showed the synthesis of a series of diamine derivatives, and N-hexadecil-1,4-butanediamine was found to be the most active compound in vitro against T. vaginalis with MIC of 2.5 μg/mL, twice more active in comparison to the reference drug metronidazole. The molecular hybridization of lycorine with diamines was impaired by the unsuccessful synthesis of the lycorine mesilate, a key intermediary on the synthetic route. However, six new lycorine ester derivatives were synthesized.
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Sanon, Aouba Albertine M. A. "Purification et caracteristiques physico-chimiques de la n-acetyl-beta-d-hexosaminidase membranaire de trichomonas vaginalis (doctorat : interactions hotes-parasites)." Paris 11, 2000. http://www.theses.fr/2000PA114812.
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Hedlund, Charise Ann 1966. "Trichomonas gallinae in avian populations in urban Tucson, Arizona." Thesis, The University of Arizona, 1998. http://hdl.handle.net/10150/278648.
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I studied Trichomonas gallinae, a flagellated protozoan that is the causative agent of the avian disease trichomoniasis. The purpose of my study was to assess (1) the incidence of trichomonads in wild birds, (2) the prevalence of trichomonads in water sources utilized by wild birds, and (3) possible methods to control the transmission of trichomonads in water sources utilized by wild birds. I trapped 403 birds during 1994 and 1995. Approximately 1/3 of these birds tested positive for T. gallinae, however, none exhibited any signs of lesions. I collected water samples from 10 bird baths, isolating flagellated protozoa from 2 of them. I could not identify the species of flagellated protozoa. I determined that high temperatures (50°C), near ultra-violet radiation, and natural sunlight are effective against trichomonads. In addition, the highest effective dilutions of Chlorox, Nolvasan, and distilled white vinegar active against trichomonads were determined.
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Borges, Fernanda Pires. "Estudo da hidrólise extracelular de nucleotídeos em Trichomonas gallinae." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2006. http://hdl.handle.net/10183/8611.
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Trichomonas gallinae é um protozoário flagelado que parasita o trato digestivo superior de várias aves, incluindo pombos domésticos, frangos e perus. O estudo dos mecanismos de patogenicidade deste parasito é de fundamental importância, uma vez que a infecção causada pelo mesmo tem envolvido grandes perdas econômicas. Sabe-se que além da função energética, o ATP desempenha inúmeras funções fisiológicas, como sinalização extracelular e mecanismos citolíticos. As concentrações dos nucleotídeos, tais como ATP e ADP, no meio extracelular são controladas por um grupo de enzimas denominadas ectonuncleotidases. Fazem parte deste grupo as NTPDases (nucleosídeo trifosfato difosfoidrolases) e a ecto-5´- nucleotidase, as quais participam do controle dos níveis extracelulares dos nucleotídeos e nucleosídeos. A presença dessas atividades enzimáticas pode estar associada com a virulência e evasão dos parasitos, servindo como um mecanismo de escape dos efeitos citolíticos do ATP. Portanto, este estudo teve como objetivo caracterizar as atividades da NTPDase e 5´-nucleotidase, envolvidas na degradação dos nucleotídeos extracelulares em T. gallinae. A hidrólise de ATP, ADP e AMP foi ativada na presença de cátions divalentes e a adição de quelantes de cátions no meio de incubação reduziu significativamente a atividade específica da NTPDase e 5´-nucleotidase. As enzimas apresentaram ampla especificidade de substrato, observada através da hidrólise de outros nucleotídeos trifosfatados, difosfatados e monofosfatados, quando adicionados ao meio como substrato. O KM para o ATP foi de 65,62 ± 15,55 μM e para o ADP foi de 122,66 ± 3,51 μM. A Vmax para o ATP e o ADP foi de 0,20 ± 0,03 e 0,70 ± 0,09 nmolPi/min/106 trofozoítos, respectivamente. Para o AMP, o KM foi 466 ± 57 μM, com uma Vmax de 3,70 ± 0,59 nmolPi/min/106 trofozoítos. A influência de outras enzimas que hidrolisam nucleotídeos extracelulares foi descartada através do uso de inibidores específicos. A hidrólise do ATP, ADP e AMP indicou a presença de uma cadeia enzimática na superfície do parasito, composta por uma NTPDase e uma ecto-5’-nucleotidase. A presença de atividades enzimáticas capazes de hidrolisar nucleotídeos extracelulares pode representar um mecanismo de sobrevivência dos parasitos nos seus ambientes naturais. A compreensão dos processos bioquímicos extracelulares destes parasitos pode ampliar o conhecimento a respeito dos mecanismos envolvidos no parasitismo.<br>Trichomonas gallinae is a flagellated protozoan which parasitizes a variety of birds all over the world, including domestic pigeons, chickens and turkeys. The study of patogenicity mechanisms is relevant, since the infection caused by this parasite involves significant economic loss. Besides the energetic function, extracellular ATP plays several physiological functions, such as extracellular signaling and cytolysis. Extracellular nucleotide levels are controlled by group of enzymes named ectonucleotidases. This group of enzymes includes the NTPDases (nucleoside triphosphate diphosphohydrolases) and an ecto-5´-nucleotidase, which participates in the control of extracellular nucleotide and nucleoside levels. The presence of these enzyme activities could be associated with the virulence and evasion of the parasites, escaping from the cytolytic effects of ATP. Therefore, the aim of this study was to characterize the NTPDase and 5´-nucleotidase activities, involved in extracellular nucleotide degradation in T. gallinae. ATP, ADP and AMP hydrolysis were activated in the presence of divalent cations and the addition of cation chelating agents in the incubation medium significantly decreased the specific activity of NTPDase and 5´-nucleotidase. The enzymes presented broad substrate specificity because others triphosphate, diphosphate and monophosphate nucleotides were also hydrolysed when they were added to the mixture as substrates. The KM value for ATP was 65.62 ± 15.55 μM and for ADP was 122.66 ± 3.51 μM. The Vmax values for ATP and ADP were 0.20 ± 0.03 and 0.70 ± 0.09 nmolPi/min/106 trichomonads, respectively. For AMP, KM was 466 ± 57 μM, with the Vmax value of 3.70 ± 0.59 nmolPi/min/106 trichomonads. The influence of other enzymes able to hydrolyze extracellular nucleotides was tested through the use of specific inhibitors. ATP, ADP and AMP hydrolysis indicated the presence of an enzyme chain in the surface of the parasite, composed by an NTPDase and an ecto-5´-nucleotidase. The presence of enzyme activities able to hydrolyze extracellular nucleotides can represent a survival mechanism of the parasites in their natural environments. The study of extracellular biochemical processes of these parasites can improve the knowledge related to the mechanisms involved in the parasitism.
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Duarte, Mariana. "Atividade anti-trichomonas vaginalis de moléculas produzidas por basidiomicetos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/40410.
Full textAbstract:
O protozoário flagelado, Trichomonas vaginalis, causa a tricomonose, a doença sexualmente transmissível (DST) não viral mais comum no mundo. Metronidazol e tinidazol são os dois fármacos de escolha recomendados pelo Food and Drug Administration (FDA, USA) para o tratamento da tricomonose humana. Entretanto, isolados de T. vaginalis clínicos ou laboratoriais resistentes e reações adversas comuns têm sido reportados. Sabe-se que fungos produzem moléculas bioativas podendo ser uma fonte em potencial de novas moléculas antiparasitárias, sendo assim, a busca por compostos naturais bioativos em basidiomicetos pode ser uma abordagem interessante para descoberta de fármacos alternativos. O objetivo desse estudo foi investigar a presença, purificar e identificar substâncias com atividade anti-Trichomonas no meio de cultivo de micélios de basidiomicetos. Para a obtenção dos compostos bioativos, os basidiomicetos Amauroderma camerarium, família Ganodermataceae, e Gymnopilus pampeanus, família Cortinariceae, foram cultivados em meio caldo extrato de malte (CEM) com variação da fonte de nitrogênio e tempo de cultivo. O extrato bruto com maior atividade anti-T. vaginalis para A. camerarium (CEM + KNO3 28 dias de cultivo) foi escolhido para ensaios de purificação e caracterização, que indicaram que o composto bioativo é de natureza protéica. Uma proteína sem alta identidade com outra proteína foi purificada e foi denominada amaurocina. Amaurocina apresenta atividade contra isolados clínicos de T. vaginalis – TV LACH1 e TV LACM2 – (CIM= 62,4 μg/mL), sendo um isolado resistente ao metronidazol (TV LACM2), e contra o isolado ATCC 30236 (CIM= 31,2 μg/mL). A Amaurocina também apresenta atividade próinflamatória por induzir aumento da liberação de óxido nítrico de neutrófilos, o qual é um importamente mecanismo de defesa do hospedeiro durante a infecção parasitária. Para G. pampeanus, os extratos mais ativos foram produzidos em meio CEM + KNO3 por 28 dias de cultivo e CEM + KNO3 por 21 dias de cultivo, porém a purificação desses extratos é necessária. Esses resultados estão em concordância com o alto potencial de produção de biocompostos dos basidiomicetos, o qual tem sido reportado na literatura por décadas.<br>The flagellated protozoan, Trichomonas vaginalis, causes trichomonosis, the most common non-viral sexual transmitted disease (STD) in the world. Metronidazole and tinidazole are two drugs of choice recommended by Food and Drug Administration (FDA, USA) for treatment of human trichomonosis. However, clinical or laboratory-generated drug-resistant isolates of T. vaginalis and common adverse reactions have been reported. It is known that fungi produce bioactive molecules and they can be a potential source of new antiparasitic molecules. Thus, in order to improve the current chemotherapy of T. vaginalis infection, the search for natural bioactive compounds in basidiomycetes can be an interesting approach to discover alternative drugs. The aim of this study was to investigate the presence, to purify and to identify substances in cultivation of basidiomycetes’ mycelia, which have anti-Trichomonas activity. Mycelia of basidiomycete Amauroderma camerarium, family Ganodermataceae, and Gymnopilus pampeanus, family Cortinariceae, were transferred to flasks containing malt extract broth (MEB) medium with variation of the nitrogen source and time of growth. The preparation with higher anti-T. vaginalis activity (MEB + KNO3 28 days of growth) for A. camerarium basidiomycete was chosen for purification and characterization assays, that indicated that the bioactive compound is a protein-like molecule. A protein without high homology with any other protein was found and was named amaurocine. Amaurocine presents activity against clinical isolates of T. vaginalis – TV LACH1 and TV LACM2 – (MIC=62.4 μg/mL), one of these a metronidazole-resistant isolate, and it presents activity against the T. vaginalis ATCC 30236 isolate (MIC=31.2 μg/mL). Amaurocine also presents proinflamatory activity. Since it was able to enhance nitric oxide release from neutrophils, which is an important host defense mechanism during the parasitic infection. For G. pampeanus, the most active extracts were produced in MEB + KNO3 28 days of growth and MEB + KNO3 21 days of growth, but further steps of purification are necessary. These results are in agreement with the high potential of biocompounds production of basidiomycetes that has been reported in the literature for decades.
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Rukasha, Ivy. "Characterization and drug resistance of Trichomonas vaginalis clinical isolates." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/30760.
Full textAbstract:
Sexually transmitted infections (STIs) are a major cause of acute illnesses, infertility, long term
disability and death with far reaching health, social and economic consequences. Trichomonas
vaginalis is the causative organism of trichomoniasis which classically presents in women as a
malodorous green-yellowish discharge accompanied by itching and burning. In men infection
can cause non-gonococcocal urethritis and chronic prostatitis. Complications of T. vaginalis
include preterm delivery, low birth weight, predisposition to HIV infection and cervical cancer.
Previous studies in South Africa have focused mostly on T. vaginalis detection with reported
rates of prevalence of T. vaginalis infections ranging between 20% to 49%. Despite estimates
showing T. vaginalis being the most prevalent sexually transmitted disease worldwide, very
little is known about the genetic diversity of T. vaginalis clinical isolates. Furthermore, the
degree of metronidazole resistance in a particular setting needs to be investigated, since this has
implications on the treatment regimen of trichomoniasis.
The purpose of this study was: i) To detect T. vaginalis in HIV positive female patients from
the Anti-Retroviral clinic of the Tshwane District Hospital, Pretoria using three methods,
namely microscopy, culture and PCR; ii) To characterize T. vaginalis isolates using both the
random amplified polymorphic DNA (RAPD) assay and the intergenic spacer regionpolymerase
chain reaction-restriction fragment length polymorphism (IGS-PCR RFLP) assay and iii) To phenotypically determine metronidazole resistance of the T. vaginalis isolates and
to compare the results with random amplified polymorphic DNA (RAPD) assay results.
Self-collected vaginal swabs from 380 women were included in the first part of the study.
Trichomonas vaginalis was detected using: wet mount microscopy, culture (modified
Diamond’s medium) and molecular detection using a commercial kit, Trichomonas vaginalis
240/250 IC (Sacace Biotechnology, Italy). The genetic relatedness of 92 culture positive
T. vaginalis isolates was determined. Five primers (TV1, TV2, TV3, TV5 and TV6) were used
for the RAPD assay. The PCR-IGS-RFLP products were digested with five enzymes, namely:
AluI, HinfI, RsaI, Sau3AI and Tsp509. A 24 h and 48 h interval microtiter assay was used to
detemine the metronidazole antimicrobial susceptibility of 30 T. vaginalis isolates.
A total of 8% (30/380) of specimens were positive for T. vaginalis using microscopy, 24%
(92/380) of specimens were positive using culture and 31% (118/380) of the specimens were
positive using the commercial PCR kit Trichomonas vaginalis 240/250 IC (Sacace
Biotechnology, Italy). RAPD assay analysis showed a high level of genetic diversity between
the different T. vaginalis isolates. The dendrogrammes obtained from the RAPD markers
grouped the 92 T.vaginalis isolates into between nine to 24 clusters with a 70% similarity,
while the PCR-IGS RFLP assay results for the isolates were genetically indistinguishable. The
minimal inhibitory concentration (MIC) for metronidazole was between 0.06 to 25 μg/ml.
Only 6% (2/30) of the T. vaginalis isolates were resistant. The dendrogrammes constructed in
the second part of the study did not group the metronidazole resistant isolates together in one
cluster. No link between resistance and a specific T. vaginalis genotype could be indicated.
This study proved that PCR is a more sensitive diagnostic tool for the detection of T. vaginalis
to improve the diagnosis of trichomoniasis. A high prevalence of T. vaginalis in HIV positive
women in South Africa was observed. The RAPD assay proved to be useful in discriminating
between the different T. vaginalis isolates, while the IGS-PCR RFLP assay was not a suitable
marker. In future, other T. vaginalis genes, such as the ferredoxin and beta-tubulin genes could
be investigated to determine the genetic variability of T. vaginalis isolates. Although
metronidazole is the only antimicrobial drug used for treatment of trichomoniasis in South
Africa, a low prevalence of in vitro resistance was found. This study emphasized the
importance of in vitro antimicrobial drug susceptibility testing to ensure continunous screening
for possible cases of metronidazole resistance and to monitor MIC changes.<br>Dissertation (MSc)--University of Pretoria, 2013.<br>Medical Microbiology<br>MSc<br>Unrestricted
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Sugino, Raquel K. "Characterization of subtilisin-like serine proteases in trichomonas vaginalis." Scholarly Commons, 2011. https://scholarlycommons.pacific.edu/uop_etds/777.
Full textAbstract:
Trichomonas vaginalis is the etiologic agent causing human trichomoniasis, a sexually transmitted infection found worldwide. In this study, subtilisin-like serine proteases (subtilases) were examined for their putative role in cell viability. Published data of other eukaryotic protozoan parasites confirm the importance of subtilases for adhesion and invasion. Serine protease inhibitor assays show that 3,4 DIC and TPCK inhibited cell growth from 79.6 to 98.4% respectively. To examine subtilases in more detail, a number of putative subtilases were cloned from T vaginalis. Two proteases were expressed recombinantly for antiserum production. TvSUB-12 (SP12) was localized to the posterior cell surface as using immunofluorescence and a kexin homolog called TvSUB-6 (SP6), revealed perinuclear staining. This study illustrated an essential role for subtilases in trichomonad cell viability and preliminary examination of two specific serine proteases revealing two different locations in the cell. To date, both of these proteases have never been characterized in this important human parasite.
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Stockdale, Heather Dawn Blagburn Byron L. "Biological characterization of Tritrichomonas foetus of bovine and feline origin." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Biomedical_Sciences/Dissertation/Stockdale_Heather_51.pdf.
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Madden, Tanya D. "Effects of fecal contaminant Eschericia [sic] coli on the bovine venereal pathogen Tritrichomonas foetus in culture." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1453232681&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Leal, Diogo Ramos. "Estudo da campilobacteriose e tricomonose genitais bovina no Distrito Federal e Goiás." reponame:Repositório Institucional da UnB, 2012. http://repositorio.unb.br/handle/10482/11157.
Full textAbstract:
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, Programa de Pós-Graduação em
Ciências Animais, 2012.<br>Submitted by Alaíde Gonçalves dos Santos (alaide@unb.br) on 2012-09-13T13:45:24Z
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2012_DiogoRamosLeal.pdf: 470837 bytes, checksum: d797fb6fe6116d5c430378002bffff11 (MD5)<br>A Campilobacteriose Genital Bovina (CGB) e a Tricomonose Genital Bovina (TGB) são doenças de transmissão venérea que têm como algumas de suas características a ausência de sinais clínicos nos touros e a condição de portadores assintomáticos. Nas fêmeas, as principais manifestações são retorno ao estro em intervalos irregulares e aumento do intervalo de partos, esses sinais podem fazer com que essas doenças não sejam detectadas de imediato e permaneçam no rebanho trazendo prejuízos. A CGB e a TGB são responsáveis por perdas econômicas devido principalmente ao descarte e necessidade de reposição de animais subférteis, à queda na produção de bezerros e ao aumento no intervalo de partos. Exames negativos para as duas doenças são exigidos para o ingresso de um animal em centrais de coleta e processamento de sêmen, bem como em transações comerciais internacionais. Devido à importância dessas doenças, o objetivo deste trabalho foi estudar a prevalência da CGB e da TGB na região do Distrito Federal e entorno, bem como em criatórios da raça Curraleiro Pé- Duro em fazendas localizadas nos estados do Distrito Federal e Goiás. Para detecção da CGB foi utilizado o exame de imunofluorescencia direta (IFD) e para TGB o cultivo em meio de Diamond. Os estudos demonstraram a presença da CGB em alguns animais abatidos em frigoríficos do Distrito Federal e entorno e em alguns rebanhos de Curraleiro Pé-Duro, determinando a necessidade de diagnóstico dessa enfermidade em rebanhos que apresentem baixos índices reprodutivos, bem como em rebanhos que comercializem reprodutores. O cultivo para TGB não apresentou resultados positivos, o que não significa a ausência do agente nesses rebanhos, mas levanta a necessidade de estudos mais amplos com outros métodos mais sensíveis de diagnóstico. Medidas de prevenção e controle da CGB e da TGB, bem como algumas práticas de manejo foram avaliadas e apresentadas neste trabalho. _______________________________________________________________________________________ ABSTRACT<br>The bovine genital campylobacteriosis (BGC) and the bovine genital trichomoniasis (BGT) are venereal transmitted diseases which absence of clinical signs in bulls and the male carrier state are some of their characteristics. In females, the main manifestations are return to estrus (repeated breeding) at irregular intervals and elongation of the calving interval, these signals can be not detected and remain in the herd resulting in economic loss. The BGC and the BGT are responsible for economic losses due to the need for disposal and replacement of infected animals, the reduction in calving rate and the increase in calving interval. Negative tests are required for a bull to enter in an artificial insemination centre, as well as in international trades. The aim was to study the prevalence of BGC and BGT in the region of the Federal District and the surrounding areas, as well as herds of Curraleiro Pé-Duro breed on farms located in the states of the Federal District and Goiás. To detect BGC, it was used the direct immunofluorescence (DIF) survey and to BGT cultivation on Diamond`s medium. The results have shown the presence of BGC in animals at slaughterhouses in the Federal District and surrounding areas and in some herds of Curraleiro Pé-Duro, exposing the need for the diagnosis of disease in herds that have low reproductive rates, as well as trading in livestock breeding. The cultivation for BGT did not show positive results, which does not mean the absence of the agent in these herds, but it alerts to the necessity in further studies with others diagnostic methods. Measures of prevention and control of BGC and BGT and some management practices have been reviewed and are presented in this study.
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Goodall, Gordon. "Studies on sulphur amino acid metabolising enzymes of trichomonas vaginalis." Thesis, University of Glasgow, 2001. http://theses.gla.ac.uk/1806/.
Full textAbstract:
Methionine--lyase (MGL) from Trichomonas vaginalis has been crystallised and the structure solved by molecular replacement at 2.2 A. The enzyme has a similar overall secondary structure arrangement as the search model, cystathionine -lyase from Escherichia coli, but differs in the active site. In addition to the holoenzyme, the structure of the enzyme in complex with the acetylenic suicide inhibitor L-propargylglycine has also been solved. This has revealed the mechanism of inhibition by this compound. It has also provided insights into the catalytic mechanism of the enzyme and allowed the postulation of a scheme for its action. Particularly, this predicts core roles for active site tyrosine and cysteine residues (111 and 113, respectively). To test the hypothesised mechanism of catalysis, seven site-directed mutants were produced. The activities of the mutants were determined and the structure solved for one of the most interesting. The resulting data confirm the mode of action of L-propargylglycine and also reveal a proton relay which activates the important active site cysteine which mediates much of the enzyme activity. This mechanism is substantially different from that proposed for other members of the same family of enzymes and explains the substrate specificity of MGL. The structure also reveals a potential role for the enzyme. The active site cysteine is positioned ideally to form an internal persulphide with a sulphur atom released from the substrate. This implies a possible role for the enzyme in iron-sulphur cluster formation in an analogous fashion to the enzyme, cysteine desulphurase. Cultivation of the parasite in medium supplemented with L-cysteine has revealed reduced expression of the enzyme. This is the first demonstration of part of the de novo synthesis of cysteine in the T. vaginalis.
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Wakukawa, Christopher Keith. "The recombinant expression and localization of TvCP2 of trichomonas vaginalis." Scholarly Commons, 2012. https://scholarlycommons.pacific.edu/uop_etds/813.
Full textAbstract:
Trichomonas vagina/is, one of the most common sexually transmitted diseases, has been shown to increase patients' susceptibility to HIV infection and cervical cancer; moreover, resistance to metronidazole is increasing, and new drug targets must be identified in order to combat resistant strains. T vagina/is expresses cysteine proteases that have been implicated in vaginal epithelial apoptosis as well as immune system evasion. In the past the various cysteine proteases have been studied as a group, and the following work examines, one specific protease, TvCP2, in detail through Western blot analysis, immunofluorescent staining, and recombinant expression. The experiments 5 presented here suggest that aT l-CP2 over-expressing transfectant line processes CP2 and sequesters it in cellular compartments. Previous data gives strong evidence of the secretion of cysteine protease CP4 and hints at the possibility of CP2 secretion as well; however, our results show no co-localization between CP2 and CP4 in T l-CP2 over expressing transfectants, suggesting separate trafficking and different roles. To better characterize CP2 function, we attempted to express active, recombinant protein. Although Pichia pastoris serves as a reliable expression vehicle, a processing event following translation ofTvCP2 appears to have cleaved the pro-domain and, along with it, the a-secretion signal, trapping active TvCP2 within the cellular pellet. A thioreoxintagged version ofTvCP2 has been expressed in E. coli, and preliminary experiments show it may auto-activate under certain conditions, but further experimentation is required to confirm the presence of active CP2 within the fraction purified from these cells.
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Faucher, Ryan Michael John. "CHARACTERIZATION OF PHYTOCYSTATIN-LIKE CYSTEINE PROTEASE INHIBITORS OF TRICHOMONAS VAGINALIS." Scholarly Commons, 2017. https://scholarlycommons.pacific.edu/uop_etds/2970.
Full textAbstract:
Trichomoniasis is a common STD caused by the parasitic protozoan Trichomonas vaginalis. The parasite is estimated to have infected roughly 3.7 million Americans. Complications from trichomoniasis can lead to cervical cancer in women and prostate cancer in men. One of the mechanisms of the parasite employs is using cysteine proteases to break down the cellular matrix of its host. However, three endogenous phytocystatin-like protease inhibitors have been found within the parasite’s genome. By recombinantly expressing these cystatins we have been able to test their ability to inhibit cysteine proteases such as papain and those found in T. vaginalis to find their effectiveness. By characterizing these inhibitors, it appears that they are effective at reducing the ability of T. vaginalis cysteine proteases and thus could be useful against the pathogenicity of the parasite.
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Meysick, Karen C. "Trichomonas vaginalis and vaginal flora: Interactions in a mouse model." Thesis, University of Ottawa (Canada), 1990. http://hdl.handle.net/10393/5972.
Full textAbstract:
The flagellated parasite, Trichomonas vaginalis, is one of the most commonly encountered genital pathogens. Despite its frequent incidence, pathogenic mechanisms of T. vaginalis are not well characterized. The first section of this project involved the ability of T. vaginalis to grow in serum-free medium. By employing a cell culture system, it was demonstrated that T. vaginalis can exhibit growth in the absence of serum. McCoy cells utilized in the system did not appear to secrete growth factors responsible for this proliferation. The second part of this project involved establishment of a mouse model for T. vaginalis infection and subsequent employment of the model in determining the effects of T. vaginalis on vaginal flora and pH. After the endemic flora and pH in mice were identified, other factors which may have influenced flora, were investigated. Both estrogenization and inoculation of media appeared to have no effect on individual vaginal species, and only appeared to increase the number of species found per mouse. T. vaginalis infection did not appear to alter vaginal pH or flora in vivo. In vitro studies of the interaction between T. vaginalis and Lactobacillus acidophilus indicated that indirect factors, such as secreted products, may mediate the alteration in flora and pH evident during infection.
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Ardalan, Shahed. "Identification of heme- and hemoglobin-binding proteins in Trichomonas vaginalis." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27441.
Full textAbstract:
Trichomonas vaginalis is the cause of human trichomoniasis. Although acquisition of iron by binding to host hemoglobin through distinct receptor(s) has been described in this parasite, no specific hemoglobin-binding site has been reported.
Our hypotheses were: (1) hemolytic activity of T. vaginalis isolates correlates with the virulence, and (2) T. vaginalis binds hemoglobin through a specific surface receptor.
The in vitro hemolytic activities of four T. vaginalis strains were examined. No correlation between hemolytic activity and virulence in different isolates was found.
Using hemoglobin-affinity chromatography, two protein bands of approximately 48 and 63 kDa were detected, the former binds preferentially to heme. Mass spectral analysis indicated that the 48- and 63-kDa proteins had significant homology with the subunits of two T. vaginalis adhesins: AP51 and AP65, respectively.
This study confirms the existence of multifunctional proteins in T. vaginalis, which enable the parasite to survive in a constantly changing environment like human vagina.
32
Thong, Kam-Wah. "Biochemistry of sulphur-containing amino acids in trichomonads." Thesis, University of Glasgow, 1986. http://theses.gla.ac.uk/1635/.
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Lemos, Patrícia Abreu Pinheiro de. "Prevalência e validação dos testes para diagnóstico de Trichomonas vaginalis em mulheres grávidas, não grávidas e portadoras do HIV." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/6834.
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Previous issue date: 2017-02-04<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>Introduction Trichomonas vaginalis is a flagelate protozoa found in
genital human secretions. Tricomoniasis is considered the most prevalent non
viral sexually transmitted disease worldwide. Pregnant women and population
with immunossupression had the highest frequencies in accord with literature.
Purposes The presente study aimed firstly at the systematic review
“Trichomonas vaginalis, genetic variation, and HIV-positive women” and
secondly focused at the original article “ Association between T. vaginalis in
pregant, non-pregnant and HIV-positive women” in order to: a) establish the
prevalence of diagnostic techniques in 3 groups of women; b) verify whether
imunossupression and/or coinfection conditions represents a risk fator for
acquiring T. vaginalis; d) evaluate the accuracy of diagnostic techniques taking
PCR as gold standard. Methods The study population included 309 women
receiving care at 3 referral public healthcare centers in Goiânia. Pregnant
women (100) at Dona Iris Maternity and General Hospital, non-pregnant
women at Federal University of Goiás’ Teaching Hospital and 103 HIV-positive
women in heathcare at an outpatient clinic of the Tropical Diseases Hospital
in Goiânia, Goiás, Brazil. The parasite has been detected comparatively
through 4 diagnostic techniques: wet mount, culture, Papanicolaou’s smear
and PCR. Accuracy from all techniques was performed in the three women
population and PCR was considered gold standard. Results The present
study found a positive association between T. vaginalis’ frequency in HIV
positive compared with non-pregnant women (ODDS RATIO (OR) 2,26).
Comparisom between pregnant women and the non-pregnant women control
group demonstrated no association (OR 1,07). PCR technique and wet mount
presented the most elevated percentage in the pregnant and HIV positive
groups correlated with the women control group. Culture presented almost the
same acuracy percentages in the three groups (sensibiity) and the stainning
techniques were the most sensibles however with the lowest specificities due
to the vast number of false positives (FP). Precancerous lesions were
associated with T. vaginalis’ presence both in pregnant and HIV positive
women (OR=4,53 and OR-2,12). Conclusion T. vaginalis’ frequency in non-
Abstract xvi
pregant-women was 18%, in pregnant women was 19% and in HIV positive
was 33%. Physiological immunossupression (pregnancy) did not represent
risk factor for T. vaginalis’ infection however coinfection for HIV represented
risk factor. Accuracy of diagnostic techniques (wet mount and culture)
presented higher sensitivitie rates in HIV-positive women (54% e 70%).
Cultured T. vaginalis stained by Quick Panoptic presented lower specificity
rates in the 3 study groups.<br>Introdução Trichomonas vaginalis é um protozoário flagelado
encontrado em secreções genitais humanas. A Tricomoníase é considerada
a doença sexualmente transmissível não viral mais frequente no mundo.
Gestantes e portadoras do vírus da imunodeficiência são as que têm
apresentado frequências mais elevadas. Objetivos O presente estudo
realizou uma revisão sistemática “Trichomonas vaginalis, genetic variation,
and pathogenicity” e um artigo original intitulado “Association between T.
vaginalis in pregnant, non-pregnant and HIV-positive women” no intuito de: a)
estabelecer a frequência dos testes de diagnóstico para detecção do parasito
nos 3 grupos de mulheres; b) verificar se as condições de imunossupressão
ou coinfecção são fatores de risco para T. vaginalis; c) avaliar a acurácia das
técnicas de diagnóstico tendo como padrão-ouro a reação em cadeia da
polimerase (PCR). Métodos A população do estudo foi constituída por 309
mulheres atendidas em três hospitais de referência de Goiânia: gestantes no
Hospital e Maternidade Dona Iris (HMDI), 106 não gestantes atendidas no
Hospital das Clínicas/ Universidade Federal de Goiás, e 103 HIV-positivas
atendidas no Hospital de Doenças Tropicais da secretaria estadual de saúde,
Goiânia, Goiás, Brasil. A detecção do parasito foi realizada comparativamente
através de quatro técnicas de diagnóstico: exame a fresco, cultura, citologia
de Papanicolaou e PCR. A acurácia das técnicas foi realizada para as três
populações de mulheres onde a PCR foi considerada o padrão ouro.
Resultados O presente estudo encontrou chance significativa de associação
entre a frequência de T. vaginalis em HIV positivas e a sua frequência em não
grávidas representada pelo ODDS RATIO (OR) 2,26. A comparação entre
gestantes e o grupo controle de não gestantes não apresentou chance
significativa (OR=1,07). A PCR e o exame a fresco apresentaram os
percentuais mais elevados no grupo das gestantes e das HIV positivas e a
sensibilidade de ambas foi também mais elevada nos dois grupos em relação
ao grupo de não grávidas. A cultura apresentou percentuais de acurácia
quase que semelhante nos 3 grupos (sensibilidade) e as técnicas coradas
foram as mais sensíveis, porém as menos específicas devido ao elevado
Resumo xiv
número de falsos positivos (FP). A presença de lesões pré-cancerígenas
esteve associada à presença de T. vaginalis tanto no grupo das grávidas
quanto no das HIV positivas (OR= 4,65 e OR= 2,14). Conclusão A frequência
de T. vaginalis em mulheres não grávidas foi 18%, em gestantes foi 19% e em
portadoras do HIV foi 33%. A imunossupressão fisiológica (gravidez) não é
fator de risco para T. vaginalis, sendo que a co-infecção pelo HIV é fator de
risco. No teste de acurácia o exame a fresco e a cultura apresentaram taxas
de sensibilidade maior no grupo das HIV-positivas (54% e 70%). Os
percentuais de especificidade da cultura corada apresentaram-se baixos nos
3 grupos.
34
Cortez, Carbonell Luis Félix, and Herbozo Mariella Mónica Razzo. "Prevalencia de Trichomonas vaginalis en gestantes durante el primer trimestre de embarazo : en el Instituto Especializado Materno Perinatal durante el periodo mayo-julio 2004." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2004. https://hdl.handle.net/20.500.12672/2253.
Full textAbstract:
Dentro de las Enfermedades de Transmisión Sexual, la importancia de Trichomonas vaginalis es diversa. Esto debido al desconocimiento de la población de la existencia de este parásito y en muchos casos por no tener acceso a los servicios básicos de salud que permitan educar y al mismo tiempo evitar una posterior cadena de contagio. Es importante conocer cuales son las consecuencias que puede traer el padecer la infección y considerar que infectarse es innecesario, pues como en toda Enfermedad de Transmisión Sexual esta se puede y se debe prevenir.
La importancia que se le da en nuestro país esta relacionada muchas veces con la disponibilidad de medios para realizar el diagnóstico, o del uso solamente de criterios clínicos en su identificación.
La investigación llevada a cabo en los Servicios de Ginecología del Instituto Especializado Materno Perinatal entre los meses de Mayo a Julio del 2004 tiene como objetivo determinar la prevalencia de infección por Trichomonas vaginalis en gestantes en su primer trimestre de embarazo, que acuden a consulta externa del hospital. Con esta finalidad se realizó un estudio de tipo prospectivo,descriptivo, observacional, de corte transversal.
El procedimiento se llevó a cabo luego que la paciente fue informada debidamente y firmó la hoja de consentimiento, de acuerdo a lo que reglamenta la Declaración de Helsinki. (Anexo 04)
La toma de muestra de secresión vaginal, se realizó con ayuda del Gineco-Obstetra en los consultorios del hospital. La población tomada en cuenta para el estudio cumplía con los requisitos de: Encontrarse dentro del primer trimestre de embarazo, no haber tenido tratamiento contra Trichomonas vaginalis, no haber sido tratada con duchas o lavados vaginales previos al examen ginecológico.
Tomada la muestra esta fue procesada dentro de los quince minutos de obtenida. Se utilizó para esto el medio de cultivo In Pouch TV, además se realizó el examen directo de la secreción, obteniéndose un resultado preliminar que en algunos casos no fué el mismo luego de ser cultivado.
Las muestras fueron incubadas y leídas luego de 24, 48, 72 horas, cuarto y quinto día, llevándose un registro de los resultados que se obtenían luego de las lecturas.
Se obtuvo muestras de un total de 105 pacientes, las que cumplían con los criterios de inclusión de nuestro estudio. De las 105 pacientes estudiadas, 6 presentaron resultados positivos al cultivo para Trichomonas vaginalis, lo que representa un 5,7% de infección en esta población. Las gestantes presentaron al mismo tiempo un rango de edad que fue de los 16 a los 40 años, período en el que muchas de ellas aún mantenían relaciones sexuales.
Dentro de los signos y síntomas observados en las gestantes se encuentran el flujo vaginal anormal (abundante), mal olor, ardor y prurito.
El flujo vaginal presentó características como el aspecto que varió de grumoso, cremoso, espeso, a líquido y mucoso que constituyó el flujo normal. En el color se observó una variedad de ellos que iban desde el transparente, blanco, blanco-amarillento, blanco-sanguinolento, amarillo, amarillo-verdoso y verde.
Se hace también una comparación de los antecedentes de estas pacientes, en relación al uso o no de métodos anticonceptivos, uso de preservativos de la pareja y si compartían una o mas parejas sexuales; todo esto relacionado con la positividad al cultivo para Trichomonas vaginalis. Se evalúa también la importancia que existe entre el grado de instrucción de las gestantes y su ocupación, versus los cuadros de positividad al cultivo.
Se concluye que es necesario hacer una evaluación mas completa de las pacientes gestantes que son atendidas, no solo en las etapas iniciales del embarazo, sino durante toda la gestación. Así mismo se debe utilizar métodos más sensibles de identificación para el diagnóstico de Trichomonas vaginalis; debido a que no solo se deben considerar criterios clínicos en el diagnóstico, pues esta demostrado que el mejor diagnóstico es la observación directa del parásito.<br>Tesis
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McKie, Amanda Elaine. "Molecular and biochemical characterisation of Methionine γ-lyase from Trichomonas vaginalis". Thesis, University of Glasgow, 1997. http://theses.gla.ac.uk/1808/.
Full textAbstract:
Two methionine -lyase gene homologues, mgl1 and mgl2 have been isolated from Trichomonas vaginalis using a degenerate oligonucleotide/PCR approach. Degenerate oligonucleotides designed against cystathionine -lyase from yeast, rat and human were used in the PCR experiments. mgl1 and mgl2 are present at single copy in the T. vaginalis genome and are expressed to give 1.3kb mRNAs. The two genes have extremely short 5' untranslated regions. The predicted molecular mass of MGL1 and MGL2 are 42.9 and 43.1 kDa, respectively. High homology exists at the amino acid level between the two T. vaginalis methionine -lyase gene homologues and methionine -lyase from Pseudomonas putida and cystathionine -lyase from a range of organisms and other related sulphur amino acid-metabolising enzymes. The two methionine -lyase homologues were cloned into expression vectors and recombinant proteins purified and subsequently characterised. Biochemical characterisation of rMGL1 and rMGL2 revealed that both recombinant proteins were able to break down methionine, catabolise homocysteine at high rate and also able to metabolise cysteine and O-acetyl L-serine. Interestingly, the recombinant proteins were not able to break down cystathionine. The two proteins were expressed in T. vaginalis, as judged by ~43 kDa proteins being detected in T. vaginalis lysates and soluble extracts by Western blot analysis. Tritrichomonas foetus and Tritrichomonas augusta do not possess the ability to breakdown homocysteine and are thought not to contain methionine -lyase. Interestingly, however, antibodies raised against rMGL1 and rMGL2 recognised proteins of various molecular weights and upon immunostaining with intact parasites, it is probable that the Golgi apparatus of these parasites were recognised by the anti rMGL1 and rMGL2 sera. For T. vaginalis, immunostaining using the anti rMGL1 and rMGL2 sera revealed a staining of the nucleus and a more general staining of the cytoplasm of these parasites.
36
Okumura, Cheryl Yoshi Matheny. "The role of lipophosphoglycan in the pathogenesis of Trichomonas vaginalis infection." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1568430781&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
Full text
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Schneider, Rachel Ellen. "Proteome analysis of the Trichomonas vaginalis hydrogenosome and putative import machinery." Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=1835545431&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Thomas, Rebecca Claire. "Molecular epidemiology of Trichomonas gallinae in European Turtle Doves (Streptopelia turtur)." Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/18558/.
Full textAbstract:
Disease is usually ignored as a potential driver of species decline. This is concerning since disease could have a greater impact on a species as it becomes vulnerable to other extinction risks. This thesis investigated Trichomonas gallinae infection in the UK’s fastest declining farmland bird, the European Turtle Dove Streptopelia turtur. It employed molecular techniques to acquire data on parasite prevalence and identify strains, and trialled the application of Next Generation Sequencing technology to disease surveillance. Overall, 50 adult Turtle Dove samples from 2011-2015 were analysed and temporal variation in strain frequency was revealed. A degree of population structure in T. gallinae infecting different Turtle Dove populations (France 2014, n=40; Senegal, n=28) was apparent, along with some evidence of wide-ranging parasite dispersal, indirectly through their host. The potential risk of shared resources as a transmission route of T. gallinae was investigated with 226 food and 117 water samples screened for its presence. Evidence suggested T. gallinae was regularly present in both food and water resources. This has important implications for supplementary feeding being a conservation management tool. The reservoir of T. gallinae in the UK was reviewed by sampling potential hosts of Columbidae (n=166), Galliformes (n=13) and Passeriformes (n=90). The detection of strains other than the finch epidemic strain in free-ranging Passerines revealed a greater level of genetic heterogeneity than previously shown in other studies. There were no significant associations between T. gallinae strain infection or coinfection with haemosporidians and measures of reproduction, body condition or post-fledging survival in Turtle Doves however, sample sizes were small. Overall, this study increases our understanding of the epidemiology of T. gallinae both in the wider bird population and a species of Vulnerable conservation status. It demonstrates how T. gallinae infecting wild birds is a useful model for investigating aspects of host- parasite ecology and encourages further research with this system.
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Oliveira, Lígia Rodrigues e. "Planejamento, síntese e atividade contra Trichomonas vaginalis de hidroxichalconas e ferrocenilchalconas /." São José do Rio Preto, 2017. http://hdl.handle.net/11449/150697.
Full textAbstract:
Orientador: Luis Octávio Regasini<br>Coorientador: Tiana Tasca<br>Banca: Gustavo Henrique Goulart Trossini<br>Banca: Margarete Teresa Gottardo de Almeida<br>Resumo: A tricomoníase, causada pelo protozoário Trichomonas vaginalis, é considerada a doença sexualmente transmissível (DST) não-viral mais comum do mundo. Para o tratamento da tricomoníase, nitrocompostos como o metronidazol são os mais prescritos, embora existam cepas resistentes e severos efeitos adversos. Dessa forma, é premente a busca de novos agentes tricomonicidas. No presente trabalho, foram planejadas hidroxichalconas (série I) avaliando a importância da posição da hidroxila no anel A e o anel B substituído por grupos preconizados pelo Método Manual de Topliss, além da substituição do anel B fenílico por anéis π-isoeletrônicos e hidrofóbicos. A série II foi composta por ferrocenilchalconas, avaliando a importância do ferroceno como grupo doador de ferro como anel B, tendo o anel A substituído por grupos preconizados pelo Método Manual de Topliss e anéis π-isoeletrônicos. As chalconas das séries I e II foram sintetizadas por meio da reação de condensação aldólica de Claisen-Schmidt, com rendimentos que variaram de 17 a 98%. Em linhas gerais, as ferrocenilchalconas foram sintetizadas com rendimentos superiores às hidroxichalconas, devido às últimas serem purificadas por etapas adicionais de recristalização e cromatográficas. As estruturas das substâncias foram confirmadas por Ressonância Magnética Nuclear. As chalconas com hidroxila no anel A exibiram atividade contra Trichomonas vaginalis (ATCC 30236) superior àquelas com hidroxila no anel B, sendo utilizadas para etapas...<br>Abstract: Trichomoniasis, caused by the protozoa Trichomonas vaginalis, is considered the most common non-viral sexually transmitted disease (STD) around the world. For the treatment of trichomoniasis, nitro-compounds such as metronidazole are the most prescribed, although there are resistant strains and severe adverse effects. Thus, search for new trichomonicidal agents is urgent. In the present work, hydroxychalcones (series I) were designed, evaluating importance of hydroxyl position on rings A and B, as well as ring B substituted by groups recommended by the Manual Method of Topliss, ring B replaced by π-isoelectronic and hydrophobic rings. Series II was composed by ferrocenylchalcones, assessing the importance of ferrocene as an iron donor group as ring B and ring A substituted by groups recommended by Manual Method of Topliss and replaced by π-isoelectronic rings. Chalcones of series I and II were synthesized via aldol condensation reaction of Claisen-Schmidt, in yields ranging from 17 to 98%. In general, the ferrocenylchalcones were synthesized in higher yields than the hydroxychalcones, because these last were purified by recrystallization and additional chromatographic steps. The structures of the substances were confirmed by Nuclear Magnetic Resonance. Chalcones with hydroxyl on ring A exhibited activity against T. vaginalis (ATCC 30236) higher than those with hydroxyl on ring B, being the first used for bioactivity optimization steps. Among these, the 4'-hydroxychalcone (4) ...<br>Mestre
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Liu, Yuk-Chien. "The structure, biosynthesis and functions of surface glycoconjugates in Trichomonas vaginalis." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/2351/.
Full textAbstract:
Trichomonas vaginalis causes trichomoniasis, a common sexual transmitted disease. This disease has been considered as a major public health problem, as it is associated with increased HIV transmission, adverse birth outcome and prostate cancer development. Recently, attention has been drawn to the characterization of the T. vaginalis surface molecules important for disease progression. Glycosylphosphatidylinositol (GPI) molecules are considered ubiquitous in eukaryotic organisms and are particularly abundant on the surface of parasitic protozoa, where they play essential roles in parasite survival, infectivity and pathogenesis. T. vaginalis, however, has a variety of surface virulence factors with single transmembrane domains, one exception being the major surface lipophosphoglycan-like molecule TvLPG. TvLPG is an important virulence factor involved in cytotoxicity and adhesion to the host’s cells. Although very little is known about the primary structure of TvLPG, it is well established that this molecule is a lipopolysaccharide rich in glycans and attached to the parasite membrane via a lipid anchor. The biosynthesis and transfer of GPI molecules to proteins is a posttranslational modification that involves a minimum of 15 gene products. Interestingly, none of the conserved genes involved in the biosynthesis and transfer of GPI molecules were found to be present in the genome of T. vaginalis, indicating that TvLPG has an unusual lipid anchor. Here, using a combination of cell-free systems and metabolic incorporation of radioactive sugar precursors, it was shown that T. vaginalis is indeed unable to make “classical” (i.e. with a glycan core made of mannose and glucosamine residues) GPI molecules. Using a combination of mass spectrometry and chemical treatments, together with the in vivo incorporation of radioactive precursors, it was determined that: 1) TvLPG does not contain peptides or amino acids, further corroborating its identity as a lipopolysaccharide; 2) rhamnose, galactose and N-acetylglucosamine are the main constituents of this glycoconjugate; and 3) TvLPG is susceptible to the action of phosphatidylinositol-phospholipase C (PI-PLC) and serum phospholipase D (PLD), but resistant to mild alkaline treatment, suggesting inositolphosphoceramide (IPC) as its main phospholipid anchor. Furthermore, the compositional analysis corroborated rhamnose as the major carbohydrate component of TvLPG making the rhamnose biosynthetic pathway a possible drug target for the treatment of trichomoniasis. It was further shown that classical and novel approaches can be combined to identify and validate potential drug target genes essential for TvLPG biosynthesis starting with the rhamnose biosynthetic pathway. Digital transcriptomics analysis combined with sugar nucleotide pool analysis and bioinformatics was carried out to investigate genes involved in rhamnose biosynthesis and additional genes involved in sugar nucleotide, inositol and sphingolipid biosynthesis and sugar transfer. The analysis revealed that all single copy genes and at least one copy of a multiple copy gene family were expressed. During the analysis, single copy genes important for TvLPG biosynthesis were identified and were mostly derived from genes involved in sugar nucleotide biosynthesis rather than from genes involved in inositol and sphingolipd biosynthesis and sugar transfer. The list included five genes of the sugar nucleotide metabolic pathway, three genes of the inositol metabolic pathway, two genes of the sphingolipid metabolic pathway and one glycosyltransferase gene. However, only one gene (UDP-N-acetylglucosamine pyrophosphorylase guanylyltransferase) was considered as additional targets, as they were single copy and important for biosynthesis of UDP-GlcNAc, important building blocks of TvLPG. A disruption of the remaining genes would not have disrupted the biosynthesis of TvLPG precursors, as alternative routes were available which could be taken to synthesis a TvLPG precursor. Further, at the genetic level, several novel strategies were attempted to generate gene-deficient parasites, including a lectin selection approach, a positive/negative selection approach and a destabilisation domain approach, as the classical approach using targeted gene replacement with a double cross-over event did not yield gene-deficient parasites with correct integration. Two genes involved in rhamnose biosynthesis, TvrmlC-1 (Tvag_313960) and TvrmlD (encoding for UDP-6-deoxy-D-xylo-4-hexulose 3,5-epimerase and UDP-6-deoxy-L-lyxo-4-hexulose reductase, respectively) were chosen as targets. Low transfection efficiency and poor luck prevented the generation of TvrmlC-1 and TvrmlD knockout parasites. As no additional selectable marker apart from the neomycin phosphotransferase gene was available, several additional selectable markers were tested. Although puromycin N acetyltransferase did not work to confer resistance to puromycin in transgenic T. vaginalis parasites, streptothricin acetyltransferase and blasticidin S-deaminase still need to be tested, as both antibiotics were able to kill wild-type parasites. On the protein level, out of the four putative proteins involved in rhamnose biosynthetis in T. vagingalis, TvrmlB-D were expressed as recombinant proteins to establish a linked assay for TvrmlD activity tests. Preliminary results were obtained for TvrmlB characterization, supporting the idea that the recombinant protein of TvrmlB is active in a modified bacterial rmlB activity assay, while the biochemical characterization of TvrmlC and TvrmlD is pending.
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Sethowa, Jonas Tshoene. "Trichomonas vaginalis and bacterial co-infections identified in reproductive age women." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/61667.
Full textAbstract:
Sexually transmitted infections (STIs) continue to be a significant public health problem with
an increased burden on women of reproductive age. These infections can be transmitted
between humans by means of sexual activity including vaginal intercourse, oral sex and anal
sex. Having a STI increases the risk of acquiring human immune-deficiency virus (HIV),
hence the control of STIs is recommended for HIV prevention. The most common STI disease
presentations to the public health setting in South Africa are male urethritis syndrome (MUS)
and vaginal discharge syndrome (VDS). The main pathogens responsible for these two
syndromes are: Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis.
In the late 1990s the South African health department introduced the STI syndromic
management approach into the primary health care setting. This approach aims to treat the
common causes of STI syndromes through the use of specific treatment algorithms. It is cost
effective because it allows treating the majority of STI patients without the need of laboratory
diagnosis to determine the aetiological agent. People without any clear symptoms will remain
untreated by the syndromic management approach. Little is known of the STI pathogens
circulating in reproductive age women in the Tshwane region. The purpose of this study was
to determine the prevalence of T. vaginalis and its co-infection in reproductive age women.
This study included self-collected vaginal swabs obtained from 117 consenting reproductive
age women visiting either a public health clinic or a sexual private health clinic. The swabs were cultured upon receipt in the laboratory on chocolate agar and in the InPouchTV for
detection and diagnosis of N. gonorrhoeae and T. vaginalis respectively. The Nugent scoring
system was used to diagnose bacterial vaginosis. The STI causing pathogens were detected on
different molecular platforms which included Anyplex II STI-7 real-time PCR, GeneXpert
CT/NG and GeneXpert TV.
The overall prevalence for both clinics of STIs was 13.7% (16/117) and for T. vaginalis
specifically, a 10.3% (12/117) rate was observed. A co-infection rate of 2.6% (3/117) was
observed in this study. Trichomonas vaginalis occurred mostly with C. trachomatis (12.5%)
followed by N. gonorrhoeae (6.3%). Most co-infections were observed in women of younger
than 30 years old. Age was not significantly associated with the prevalent T. vaginalis
infection in this study but being unmarried showed a significant association (p-value=0.038)
with the prevalent infection in both clinics. The high rates of Trichomonas vaginalis and
coinfections with C. trachomatis and N. gonorrhoeae observed in the asymptomatic women
visiting the two clinics provide evidence that in certain key groups the simultaneous screening
for all three pathogens should be performed.<br>Dissertation (MSc)--University of Pretoria, 2017.<br>Medical Microbiology<br>MSc<br>Unrestricted
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Foray, Nathalie Emma-Marie. "Characterization of TvDMC1 and TvSOD6 expression and function in trichomonas vaginalis." Scholarly Commons, 2009. https://scholarlycommons.pacific.edu/uop_etds/721.
Full textAbstract:
Trichomonas vagina/is is a common sexually transmitted disease, affecting women more often than men. It has only been seen to undergo mitosis, even though published studies have confinned the organism has meiotic proteins. These meiotic proteins are known to function in other organisms with a key protein in homologous recombination, DMCl. RT-PCR analysis shows low expression ofDMCl in mitotically-growing cultures, and we found that some stresses on the organism increase DMCl expression. Polyclonal antibodies raised against DMCl protein have been used to test whole celllysates of the Tl and G3 strains of Trichomonas vagina/is but no obvious expression has been detected. We also used western blot analysis to show that superoxide dismutase is expressed in the standard lab strains Tl and G3 and immunocytochemistry studies showed that HA-tagged SOD6 protein localizes in the cytoplasm. Lastly, we found that SOD protein abundance increased in the CDC085 strain compared to Tl and G3, especially under aerobic conditions.
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Buchan, Morag M. "A study of hydrolases and their release from trichomonads." Thesis, University of Stirling, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335034.
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Frasson, Amanda Piccoli. "Estudo da expressão gênica das ectonucleosídeo trifosfato difosfoidrolases (e-ntpdases) em trichomonas vagilalis e participação da sinalização purinérgica na relação parasito-hospedeiro." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/148345.
Full textAbstract:
Trichomonas vaginalis é o agente etiológico da doença sexualmente transmissível não viral mais comum no mundo, sendo registrados aproximadamente 276 milhões de novos casos de tricomonose a cada ano. O estabelecimento da infecção se deve principalmente à capacidade de adesão do parasito às células epiteliais vaginais, cervicais ou de próstata, seguida pela intensa reação inflamatória, resultado da infiltração de neutrófilos no sítio da infecção. Nucleotídeos e nucleosídeos, especialmente ATP e adenosina, são liberados para o espaço extracelular por células em situações de estresse ou injúria tecidual e desenvolvem seus efeitos sinalizadores através da ativação de purinoceptores. Ainda, as ectonucleotidases, NTPDase e ecto-5’-nucleotidase, são capazes de hidrolisar os nucleotídeos gerando adenosina e finalmente, a enzima adenosina deaminase (ADA) é responsável pela conversão de adenosina em inosina. A expressão gênica de cinco NTPDases putativas presentes no genoma de T. vaginalis foram investigadas, assim como o envolvimento da sinalização purinérgica na relação parasito-hospedeiro. Nossos resultados mostraram que diferentes isolados de T. vaginalis expressam os genes TvNTPDase1, 2, 3, 4 e 5, sendo observado o maior número de transcritos para TvNTPDase1, 2 e 4. A sequência preditiva de aminoácidos revelou a presença das cinco regiões conservadas da apirase, domínios transmembrana, sítios de fosforilação, peptídeos sinais e os prováveis sítios ativos da enzima. A análise filogenética demonstrou maior similaridade das TvNTPDases com as formas intracelulares da enzima, como as NTPDases 4 e 7 humanas e a de Saccharomyces cerevisiae. Além disso, a restrição de soro promoveu aumento significativo da atividade da NTPDase de T. vaginalis, no entanto sem corresponder com o aumento de expressão gênica de determinada(s) sequência(s). Quanto à participação da sinalização purinérgica na resposta inflamatória de células do hospedeiro frente ao parasito, foram utilizados como modelos celulares as células epiteliais vaginais (HMVII), cervicais (HeLa) e neutrófilos humanos. As linhagens HMVII e HeLa mostraram expressar todos os subtipos de receptores P1, P2X e P2Y e XI os diferentes isolados de T. vaginalis, que foram cocultivados com as células, mostraram hidrolisar eficientemente os nucleotídeos ATP, ADP e AMP. Ainda, o isolado clínico fresco TV-LACM6 foi o único a apresentar elevada citotoxicidade frente às células epiteliais vaginais e cervicais, no entanto não foi detectado aumento da liberação de ATP pelas células após o cocultivo, provavelmente devido à alta atividade da enzima NTPDase observada nesse isolado. Os trofozoítos de T. vaginalis não foram capazes de aumentar a produção de IL-8 e IL-6 pelas linhagens HMVII e HeLa, e apenas os isolados ATCC30236 e TV-LACM6 causaram aumento na secreção da citocina MIP-3α pelas células epiteliais cervicais. Finalmente, o nucleotídeo ATP e o nucleosídeo adenosina não modularam a produção dos mediadores inflamatórios investigados. Em relação aos neutrófilos, estes mostraram aumentar a produção de espécies reativas de oxigênio (ERO) e IL-8 após incubação com os trofozoítos de T. vaginalis. Os nucleotídeos e nucleosídeos da adenina e guanina não produziram efeito na produção de ERO e IL-8; no entanto, quando o nucleosídeo adenosina foi incubado junto com o inibidor da enzima ADA (EHNA) observou-se uma redução significativa da produção de ERO e IL-8 pelos neutrófilos, devido à inibição da ADA e consequentemente, ao aumento da concentração de adenosina disponível no meio extracelular. Os nossos resultados indicaram a ativação do receptor A1 dos neutrófilos nessa condição. O conjunto de dados aqui obtidos contribuiu para uma melhor caracterização da família de enzimas NTPDases de T. vaginalis assim como para um maior conhecimento acerca da influência da sinalização purinérgica na relação parasito-hospedeiro.<br>Trichomonas vaginalis is the agent of the most common non-viral sexually transmitted disease worldwide, causing 276.4 million new cases a year. The establishment of the infection is closely related to the parasite ability to adhere to vaginal, cervical and prostate epithelial cells, followed by an intense inflammatory response as result of neutrophil infiltration. Nucleotides and nucleosides, mainly ATP and adenosine, are released into the extracellular space by cells under stress or injury and they exert their signaling effects through activation of the purinoceptors. Moreover, the ectonucleotidases, NTPDase and ecto-5'-nucleotidase, are capable of hydrolyzing the nucleotides producing adenosine and finally, the adenosine deaminase (ADA) is responsible for the conversion of adenosine to inosine. We investigated the gene expression of five putative NTPDases found in T. vaginalis genome as well as the involvement of purinergic signaling on the host-parasite relationship. Our results showed that different T. vaginalis isolates are able to express TvNTPDase1, 2, 3, 4 and 5 and that TvNTPDase1, 2 and 4 are the most expressed genes. Predictive amino acid sequence revealed the presence of the five apyrase conserved regions, transmembrane domains, phosphorylation sites, signal peptides and the active sites. Phylogenetic analysis showed that TvNTPDases share more similarity with the intracellular enzymes, such as human NTPDase 4 and 7 and Saccharomyces cerevisiae NTPDase. In addition, the serum limitation caused a significant increase in NTPDase activity, but without association with the gene expression of a specific TvNTPDase sequence. Regarding the participation of purinergic signaling on the inflammatory responses against the parasite, the vaginal (HMVII) and cervical (HeLa) epithelial cells and the human neutrophils were used as cellular models. HMVII and HeLa cell lines showed to express all subtypes of P1, P2X and P2Y receptors and the different T. vaginalis isolates, which were co-cultured with the cells, showed to hydrolyze efficiently ATP, ADP and AMP. Furthermore, only the fresh clinical isolate, TV-LACM6, caused a profound cytotoxicity against the vaginal and cervical epithelial cells. Interestingly, it was not detected an increase in ATP release by the cells after cocultivation, probably due to the high NTPDase activity dislplayed by TV-LACM6 isolate. The T. vaginalis trophozoites were not able to increase the production of IL-8 and IL-6 by HMVII and HeLa cells and only ATCC30236 and TV-LACM6 isolates enhanced MIP-3α secretion by the cervical epithelial cells. Finally, neither ATP nor adenosine has modulated the production of the inflammatory mediators here investigated. Considering the neutrophils, T. vaginalis stimulated the production of reactive oxygen species (ROS) and IL-8 by these immune cells and both adenine as guanine nucleotides and nucleosides did not cause any effect on ROS and IL-8 levels. However, when adenosine was incubated with an ADA inhibitor (EHNA) we observed a significant reduction of ROS and IL-8 production by neutrophils, due to inhibition of ADA with a subsequent increase of adenosine concentration in the extracellular milieu. . Our results suggested the participation of A1 receptor in this condition. The data set obtained in this study contributed to the characterization of T. vaginalis NTPDases family as well as to a better understanding of the influence of purinergic signaling on host-parasite relationship.
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蔡住當. "Study of Trichomonas vaginalis virus in Taiwan Trichomonas vaginalis isolates." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/75572180283162028655.
Full text
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Zubáčová, Zuzana. "Studium chromosomů parazita Trichomonas vaginalis." Doctoral thesis, 2011. http://www.nusl.cz/ntk/nusl-312129.
Full textAbstract:
Charles University in Prague Faculty of Science Programme of study: Parasitology Abstract of Ph.D. thesis Chromosomes of parasitic protist Trichomonas vaginalis Zuzana Zubáčová, MSc. Supervisor: Prof. RNDr. Jan Tachezy, Ph.D. Praha, 2011 Abstract Genome sequencing and associated proteome projects has revolutionized research in the field of molecular parasitology. Progress in sequencing of parasite as well as free-living species enables comparative and phylogenetic studies and provides important data sets for understanding of basic biology and identification of new drug targets. The genome sequencing of Trichomonas vaginalis revealed surprisingly large genome size of this organism (~160 Mb) that resulted from expansion of various repetitive elements, specific gene families and large scale genome duplication. I studied genome sizes of other nine selected species from Trichomonadea group to find whether other trichomonads have undergone similar genome expansion. The measurement of nuclear DNA content by flow cytometry revealed relatively large DNA content in all tested species although within a broad range (86-177 Mb). The largest genomes were observed in the Trichomonas and Tritrichomonas genera while Tetratrichomonas contains the smallest genome. The genome sizes correlated with the cell volume however no...
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Dohnálková, Alena. "Cytosolická hydrogenáza prvoka Trichomonas vaginalis." Master's thesis, 2015. http://www.nusl.cz/ntk/nusl-343773.
Full textAbstract:
Trichomonas vaginalis is a flagellated microaerophilic protozoan from the group Excavata that cause trichomoniasis, the most common nonviral sexually transmitted disease in the world. This thesis deals with the study of hydrogenases, enzymes catalyzing reversible conversion of protons and electrons to molecular hydrogen. In T. vaginalis, hydrogenases have been identified so far only in hydrogenosomes, modified anaerobic mitochondia that are involved in energy metabolism. We proved the presence of this enzyme also in the cytosol of T. vaginalis. Among several hydrogenase paralogues present in the genome, we selected an appropriate gene for the putative cytosolic hydrogenase (C-Hyd) and verified its cytosolic localization in the cells with overexpressed C-Hyd protein. Based on the determination of hydrogenase activities in different cell compartments and fractions obtained by affinity chromatography, we demonstrated the hydrogenase activity of C-Hyd protein, which means that C-Hyd is a functional hydrogenase. Identification of hydrogenase in T. vaginalis cytosol changes our understanding of trichomonad core metabolism and opens the door for the research of unexplored metabolic capabilities of this parasite.
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Campo, Beltran Neritza. "Proteomic Analysis of Trichomonas vaginalis hydrogenosone." Doctoral thesis, 2016. http://www.nusl.cz/ntk/nusl-352081.
Full textAbstract:
Trichomonas vaginalis is a human pathogen that affects annually approximately 258 million people worldwide. This parasite possesses organelles of mitochondrial origin called hydrogenosomes, which generate ATP under anaerobic conditions. The identification of the protein content at the subcellular level may provide new targets for antiparasitic drugs developments as well as it contributes for our understanding of the organelles function and evolution. The availability of protocols for organelles purification and the complete genome sequence allow the study of the organellar proteomes using mass spectrometry and bioinformatics, providing a powerful strategy that combine cell biology and proteomics. In our research, we used several approaches to identify the protein composition in hydrogenosomes and mitosomes. We performed transcriptomic and proteomic analysis to investigate the molecular responses of Trichomonas vaginalis upon iron availability. Furthermore, the changes in the proteome during the development of metronidazole resistance were also studied. The organelles separated by differential and Optiprep-sucrose gradient centrifugation were analyzed with nano- RP-HPLC/MALDI-TOF/TOF. We also used Triton X-114 phase partitioning to separate membrane proteins and iTRAQ technique to label the peptides...
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Radhakrishna, Makki Abhijith. "Translokace proteinů do hydrogenosomů "Trichomonas vaginalis"." Doctoral thesis, 2019. http://www.nusl.cz/ntk/nusl-411952.
Full textAbstract:
Mitochondria carry out several important functions in eukaryotic cells such as energy metabolism, iron-sulfur cluster assembly, apoptosis, signaling pathways, protein quality control etc. Most mitochondrial proteins are synthesized on the cytosolic ribosomes and transported to the organelles by the cytosolic chaperones and mitochondrial protein import machinery based on specific targeting signals. Although, the basic principles of protein import have been explained, many questions remain unanswered, particularly for highly modified mitochondria such as hydrogenosomes. The aim of the study was to investigate protein translocation into hydrogenosomes of a human parasite, Trichomonas vaginalis (Tv) with a focus on the composition, function and structure of protein translocases and the role of targeting signals. The translocase of the outer membrane (TOM) is responsible for the import of most proteins into the organelle. Even though, the presence of a TOM complex in trichomonad hydrogenosomes was predicted, its components were not known. Moreover, the generic structure of the mitochondrial TOM complex was not resolved. This study showed that the TvTOM complex is highly divergent consisting of two modified core subunits - channel- forming TvTom40 isoforms and a Tom22-like protein, and two...
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Tsai, Huei-Man, and 蔡惠滿. "A novel protein kinase in Trichomonas vaginalis." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/19039734038908381808.
Full textAbstract:
碩士<br>國防醫學院<br>病理學研究所<br>83<br>Mitogen-activated protein kinases (MAPK) comprise a family of
serine/threonine-specific protein kinases that mediate intrace-
llular phosphorylation events linking receptor activation to
the control of cell proliferation and differentiation. Many
steps of this cascade are conserved and homology have been
discovered in yeast, Caenorhabditis elegans, Drosophila
melanogaster and in ma- mmalian cells. However, the role of
MAPK in organisms diverging early in the eukaryotic lineage has
not yet been studied. Comparison of 11 conserved domains from
MAPK family, we have designated degenerate primers from domains
VI and VIII for the amplification of a small DNA fragment with
138 bp by polymerase chain reaction (PCR). Sequencing of this
PCR product has re- vealed that it is almost identical to the
conserved region (LKICD FGLAR) of domain VII and denoted as
TVsERK. TVsERK was used as a probe to screen Trichomonas
vaginalis genomic DNA library. We subsequently obtained a full
length intronless DNA fragment with 1695 bp for TVERK, which
could be translated into 359 amino At the amino acid level, the
TVERK gene is 34% homologous with yeast MAPK, 31% with human
MAPK. TVERK gene was subcloned into pQE vector and expressed
in E. coli. TVERK fusion protein was partial purified and
demonstrated as a single band with 20kDa in sodium dodecyl
sulfate-polyacrylamide gel electrophoresis. A polyclonal
antibody against TVERK was raised by direct injection of TVERK
into the rabbit spleen. This polyclonal antibody recog- nized
a major protein with molecular weight of 45 kDa from T.
vaginalis. Regrowth of T. vaginalis in serum-supplemented
medium after a 6-hr starvation by serum-depletion demonstrated
that TVERK ex- pressed markedly at 4-5 hr of cultivation.
Moreover, a PKC inhi- bitor, sphingosine at 20um, did not alter
TVERK activity during the growth of T. vaginalis. The role of
TVERK in the growth or cell cycle of T. vaginalis should be
futher investigated.