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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Untersuchungen zu tanninbindenden Speichelproteinen des Rehs und anderer Wiederkäuer / Investigation of tannin binding salivary proteins of roe deer and other ruminants

Gehrke, Janin January 2002 (has links)
Am Beispiel der Wiederkäuer wurde unter Zuhilfenahme von biochemischen und molekularbiologischen Methoden die Adaptation von Pflanzenfressern (Herbivoren) an pflanzliche Sekundärmetabolite wie z.B. Tannine untersucht. Tannine können in nicht an ihren Verzehr adaptierten Spezies durch ihr Proteinbindungsvermögen die Nahrungsverwertung und damit Wachstum und Gesundheit des Pflanzenfressers beeinträchtigen (antinutritive Wirkung). <br /> Einige Wiederkäuerarten wie z.B. das Reh (Capreolus capreolus) haben in ihrem Nahrungsspektrum viele stark tanninhaltige Pflanzen, leiden aber nicht unter den erwähnten postdigestiven Konsequenzen. Eine Möglichkeit, die antinutritive Wirkung von Tanninen zu neutralisieren, besteht in der Produktion tanninbindender Speichelproteine. <br /> Der Speichel verschiedener Wiederkäuerarten wurde auf das Vorhandensein tanninbindender Proteine untersucht. Diese Arten wurden so ausgewählt, dass alle drei Ernährungstypen (Konzentratselektierer, Intermediärtyp, Gras- und Rauhfutterfresser) in den Vergleich eingeschlossen werden konnten. Als Referenzspezies wurde der Konzentratselektierer Reh herangezogen.<br /> Die Speichelproteine des Rehs und die der Intermediärtypen (Rentier, Rangifer tarandus; Damhirsch, Cervus dama; Moschusochse, Ovibos moschatus) banden ungefähr doppelt so effektiv an hydrolysierbare Tannine (Tanninsäure), wie die der untersuchten Gras- und Rauhfutterfresser (Rind, Bos taurus; und Mufflon, Ovis orientalis musimon). Diese Abstufung zeigte sich auch bei der Untersuchung der Bindung an kondensierte Tannine (Quebracho). Eine Ausnahme stellte Mufflonspeichel dar, dieser band ebenso gut an Quebracho wie die Speichelproteine der anderen Ernährungstypen.<br /> Über eine Aminosäuretotalanalyse konnte festgestellt werden, dass der Speichel einiger untersuchter Wiederkäuerarten prolinreiche Proteine (PRPs) enthielt. Unter Ausnutzung ihrer Trichloressigsäure (TCA)-Löslichkeit wurden diese angereichert und genauer untersucht. Die Analyse der TCA-löslichen Speichelproteine der Konzentratselektierer (Reh, Elch) ergab einen relativen Prolingehalt von über 35 %, während beim Moschusochsen noch 29 % gemessen wurden. In Damhirsch- und Rinderspeichel wurden keine prolinreichen Proteine gefunden.<br /> Für die TCA-löslichen Speichelproteine des Rehs konnte eine hohe Tanninbindungskapazität nachgewiesen werden. Diese banden 24 - 30 x effektiver an Tannine als die TCA-löslichen Speichelproteine des Rindes. Die Tanninbindungskapazitäten der TCA-löslichen Speichelproteine von Moschusochse und Damhirsch waren ebenfalls höher als die des Rindes, aber niedriger als die des Rehs. <br /> Die Kohlenhydrat-Analyse der TCA-löslichen Speichelproteine des Rehs erbrachte, dass es sich bei ihnen um Glykoproteine handelt. Mittels Gelfiltration und zweidimensionaler Polyacrylamidgelektrophorese konnten fünf Proteingruppen mit Molekulargewichten zwischen 15 und 50 kd sowie isoelektrischen Punkten zwischen 4,0 und 8,2 detektiert werden. <br /> Von 15 dieser Proteine konnten die N-terminalen Aminosäuresequenzen ermittelt werden. Ausgehend von diesen Informationen wurden Reh-PRP spezifische mRNAs isoliert und partiell sequenziert. Die meisten dieser Fragmente hatten eine gemeinsame 18 Aminosäuren lange C-terminale Sequenz PPPEEQPEE/QSPDEE/DSPSE. <br /> Die Suche nach Übereinstimmungen der analysierten Sequenzen mit anderen Säugetier-PRPs in der Genbank ergab keine sinnvollen Ähnlichkeiten. Die Ergebnisse können zu Informationen über tanninbindende Proteine anderer Wiederkäuer führen. Die Sequenzinformationen stellen einen Ausgangspunkt bei der Analyse der evolutiven Zusammenhänge der Cerviden dar. / Investigation of tannin binding salivary proteins of roe deer and other ruminants: <br /> In this work the adaptation of herbivores to plant secondary metabolites was investigated with help of biochemical and molecular biological methods. In unadapted species plant secondary metabolites as tannins can reduce food digestibility and thus diminish growth rate and health status (antinutritive action). Tannins act through its astringency, that means the high capacity to bind proteins, other macromolecules and metal ions. Some ruminant species feed on tannin containing plant but do not suffer from the mentioned nutritive consequences. The production of tannin binding proteins is one possible adaptation mechanism to neutralize the effects of the tannins.<br /> Saliva of six different ruminant species was investigated for the presence of tannin binding proteins. All three feeding types (concentrate selector, intermediate type and grass and roughage eater) were included in the comparison. <br /> Salivary proteins from roe deer (Capreolus capreolus, concentrate selector) and from the intermediate feeding types (rein deer, Rangifer tarandus; fallow deer, Cervus dama; musk ox, Ovibos moschatus) bound twice as effective to hydrolysable tannins (tannic acid) as those from the investigated grass and roughage eaters (cattle, Bos taurus; moufflon, Ovis orientalis). This differentiation could also be observed investigating the binding capacities to condensed tannins (quebracho) except for moufflon. Moufflon salivary proteins bound with the same intensity to quebracho as the salivary proteins from the other feeding types.<br /> Proline rich proteins (PRPs) could be accumulated from roe deer, moose and musk ox saliva by use of its solubility properties in 5 % trichloro acetic acid (TCA). Roe deer and moose TCA soluble salivary proteins contained more than 35 %, musk ox proteins 29 % proline. In fallow deer and cattle saliva PRPs could not be detected.<br /> A tannin binding assay demonstrated for the TCA soluble salivary proteins from roe deer, musk ox and fallow deer but not from cattle, that they are able to bind tannins. Roe deer salivary proteins bound 24 to 30 more effective to tannins as cattle proteins. Tannin binding capacity of the proteins from musk ox and fallow deer saliva was higher as those from cattle but lower as those from roe deer.<br /> For further analysis of ruminant tannin binding proteins we chose roe deer as reference species. Carbohydrate analysis of TCA soluble proteins from roe deer saliva showed that they were glycoproteins. With help of gel filtration and two dimensional polyacrylamid gel electrophoresis five proteins groups with molecular weights from 15 to 50 kd and isoelectric points from 4.0 to 8.2 could be detected.<br /> N-terminal amino acid sequences of 15 of the roe deer salivary TCA soluble proteins were determined by Edmann degradation. This information led to partially sequenced roe deer PRP specific cDNA. An 18 amino acid long C-terminal sequence was common in most of the clones. The obtained roe deer PRP sequences did not match with known mammalian PRP sequences from data banks. <br /> The finding in this work can lead to information about salivary tannin binding proteins in other ruminants. The sequence information represent a starting-point for the investigation of cervid evolution.
32

Imunização de cães com produtos oriundos de Lutzomyia Longipalpis em duas diferentes abordagens: Canarypoxvirus sp. expressando o gene que codifica para a proteína salivar LJM17 e/ou LJL143, e a proteína do intestino médio luloper1 como vacina a proteína salivar LJM17 e/ou LJL143, e a proteína do intestino médio luloper1 como vacina bloqueadora de transmissão

Abbehusen, Melissa Moura Costa January 2015 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-02-04T14:13:01Z No. of bitstreams: 1 Melissa Moura Costa Abbehuden Imunização...2015.pdf: 2688379 bytes, checksum: ee3a425f3866123bc591a289919d408a (MD5) / Approved for entry into archive by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-02-04T14:13:16Z (GMT) No. of bitstreams: 1 Melissa Moura Costa Abbehuden Imunização...2015.pdf: 2688379 bytes, checksum: ee3a425f3866123bc591a289919d408a (MD5) / Made available in DSpace on 2016-02-04T14:13:16Z (GMT). No. of bitstreams: 1 Melissa Moura Costa Abbehuden Imunização...2015.pdf: 2688379 bytes, checksum: ee3a425f3866123bc591a289919d408a (MD5) Previous issue date: 2015 / Fundação Oswaldo Cruz, Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / As interações entre flebótomo, parasita e hospedeiro desempenham um papel importante na transmissão da leishmaniose. As moléculas provenientes do vetor são relevantes para estas interações e incluem as proteínas da saliva e do intestino médio. Nos flebótomos, as Leishmanias passam por um ciclo de desenvolvimento complexo dentro do intestino médio sob a proteção da matriz peritrófica, necessário para a geração de formas metacíclicas infectantes. As Leishmanias são transmitidas pelos flebótomos que co-injetam parasitas juntamente com a saliva, na derme do hospedeiro. Estudos anteriores demonstraram que a imunização de cães com duas proteínas salivares (LJM17 ou LJL143) de L. longipalpis, resultaram em uma imunidade mediada por células Th1 sistêmica e local afetando a sobrevivência do parasita in vitro. Assim, o objetivo deste trabalho foi avaliar a imunidade conferida pela imunização de cães com DNA e rCanarypoxvirus expressando o gene que codifica para as proteínas salivares de L. longipalpis (LJM17 e/ou LJL143). A imunização com ambas LJL143 e/ou LJM17 induziu uma forte resposta imune humoral. A produção específica do IFN-γ foi observada apenas nas CMSP dos grupos imunizados estimuladas com a proteína. Trinta dias após a última imunização, os cães foram desafiados por via intradérmica com 107 de L. infantum na presença de saliva de L. longipalpis, e a infecção foi detectada no segundo mês após o desafio em todos os grupos. Os cães imunizados com a LJM17 apresentaram maior produção de IFN-γ, IL-2, IL-6, IL-7, IL-15, IL-18, TNF-α, IP-10 e GM-CSF durante a infecção quando comparados com os controles, indicando que o efeito da imunização induzida por LJM17 persistiu mesmo após o desafio. Adicionalmente, diversos estudos realizados no controle da malária, têm demonstrado o uso de antígenos provenientes do vetor para o desenvolvimento de vacinas bloqueadoras de transmissão. Esta estratégia altruísta de imunização visa criar anticorpos que interfiram no desenvolvimento do parasita no interior do vetor. Assim, na segunda etapa do nosso trabalho, foi testada em cães uma estratégia de imunização utilizando uma proteína extraída do intestino médio do L. longipalpis (Luloper1) para induzir a produção de anticorpos em cães saudáveis e infectados e a interrupção da transmissão no flebótomo. Dessa forma, a imunização de cães saudáveis não infectados ou infectados assintomáticos induziu uma potente produção de anticorpos, porém nenhum efeito de bloqueio de transmissão foi detectado em flebótomos alimentados com o sangue desses animais contendo promastigotas de L. infantum. / Sand fly, parasite, host interactions play an important role in the transmission of leishmaniasis. Vector molecules are relevant for such interactions and include midgut and salivary proteins. In vector sand fly species, Leishmania parasites undergo a complex developmental cycle within the midgut, protected by the peritrophic matrix that is necessary for generation of infectious metacyclics. Leishmania parasites are transmitted by sand flies that co-inject parasites and saliva, in the host’s skin. Previous studies showed immunization of dogs with two proteins (LJM17 or LJL143) from Lutzomyia longipalpis, resulted in a systemic and local Th1 cell-mediated immunity affecting parasite survival in vitro. In this work we evaluated the immunity conferredbyimmunization of dogs with DNA and recombinant Canarypoxvírusexpressing the gene encoding the salivary ofL.longipalpis (LJM17and/orLJL143). Immunization with both LJL143 and LJM17 induced a strong specific humoral response. Specific production of IFN-γ was observed only in protein stimulated PBMC immunized groups. Thirty days after last immunization, dogs were challenged intradermally with 107L. infantum in the presence of L. longipalpis saliva and infection was detected in the second month after challenge in all the groups. It was observed that dogs immunized with LJM17 presented higher IFN-γ, IL-2, IL-6, IL-7, IL-15, IL-18, TNF-α, IP-10 and GM-CSF production during infection when compared with controls, indicating that the effect of immunization induced by LJM17 persisted even after challenge. Adittionally, previous studies, mostly with malaria control, have shown the use of several vector antigens for the development of transmission blocking vaccines. This altruist strategy of immunization aims to raise antibodies that could affect the development of the parasite inside the vector. Thus, in the second stage of our work we tested in dogs an immunization using a protein extracted from L. longipalpis midgut (Luloper1) to evaluate antibodies production in healthy and infected dogs and the interruption of transmission in the sand fly. Immunization of either healthy non infected or asymptomatic infected dogs induced a potent antibodies production, but no blocking transmission effect was detect in sand flies fed with blood of these animals containing L. infantum promastigotes
33

Identification et validation de nouveaux bio-marqueurs immuno-épidémiologiques pour évaluer l'exposition humaine aux piqûres d'Anophèles, vecteurs de paludisme / Identification and validation of new immuno-epidemiological biomarkers for evaluating the human exposure to Anopheles malaria vectors

Marie, Alexandra 04 April 2014 (has links)
Le paludisme constitue un problème majeur de santé publique en zone tropicale et subtropicale. La morbidité ainsi que la mortalité sont principalement dues au parasite Plasmodium falciparum transmis à l'homme par la piqûre de moustiques femelles du genre Anopheles. Dans le but d'orienter au mieux les stratégies d'élimination du paludisme et d'une meilleure évaluation de l'efficacité des méthodes de lutte, les indicateurs mesurant le risque de transmission doivent être plus sensibles. Il a été montré que la réponse anticorps humaine contre des protéines/peptides salivaires d'Anopheles représente un bio-marqueur d'exposition aux piqûres de moustiques et pouvait être un indicateur de la transmission du paludisme. Toutefois cet outil doit être optimisé. Ce travail a ainsi un double objectif : i) valider la protéine salivaire CE5 comme bio-marqueur d'exposition aux piqûres d'Anopheles et comme indicateur évaluant l'efficacité de stratégie de lutte anti-vectorielle, et 2) identifier de nouvelles protéines salivaires comme candidat bio-marqueur spécifique à l'exposition de l'homme aux seules piqûres infectantes d'Anopheles. Tout d'abord, nous avons démontré que la réponse anticorps IgG contre la protéine CE5 pourrait être un indicateur du contact homme-vecteur, complémentaire et très sensible, en mesurant l'exposition de l'homme aux piqûres d'Anopheles et un outil évaluant l'efficacité, à court terme, des moustiquaires imprégnées d'insecticide. Par la suite, les méthodes de protéomique 2D-DIGE et de spectrométrie de masse ont permis d'identifier cinq protéines salivaires (gSG6 , gSG1b , TRIO , SG5 et la forme longue D7) qui sont surexprimées dans les glandes salivaires d'An. gambiae infectées par P. falciparum. Des peptides de chaque protéine, définis in silico, apparaissent antigéniques chez des individus exposés aux piqûres d'Anopheles, après évaluation par la technique d'épitope mapping. L'ensemble de ces travaux est non seulement une première étape pour optimiser cet outil immuno-épidémiologique évaluant le contact homme-vecteur mais démontre également la possibilité de définir un nouveau bio-marqueur qui serait spécifique des piqûres infectantes d'Anopheles. / Malaria is a major public health problem in tropical and subtropical areas. Morbidity and mortality are mainly due to Plasmodium falciparum transmitted to human individuals by the bite of female Anopheles mosquitoes. In order to orientate appropriate strategies for malaria elimination and for a better evaluation of the efficacy of control methods, the indicators measuring the risk of transmission should be more sensitive. It has been shown that the human antibody response against Anopheles salivary proteins/peptides represents a biomarker of exposure to mosquito bites and could be an indicator of malaria transmission. However, this tool must be optimized. This work has thus two objectives: i) to validate the salivary protein cE5 as biomarker of exposure to Anopheles bites and as an indicator for evaluating the efficacy of vector control strategy, and 2) to identify new salivary proteins as a candidate biomarker only specific to human exposure to infective bites of Anopheles.First, we demonstrated that the IgG antibody response to cE5 protein could be an indicator of human-vector contact, complementary and very sensitive, measuring the human exposure to Anopheles bites and a tool evaluating the short-term efficacy of insecticide treated nets. Subsequently, the proteomic methods, 2D - DIGE and mass spectrometry, allowed to identify five salivary proteins (gSG6, gSG1b, TRIO, SG5 and the long form D7) which are overexpressed in the salivary glands of An . gambiae infected by wild P. falciparum. Peptides for each protein, identified in silico, appear antigenic in individuals exposed to Anopheles bites, after the evaluation by the epitope mapping technique.Altogether, this work is not only the first step to optimize this immuno-epidemiological tool assessing the human-vector contact, but also demonstrates the possibility to define a new biomarker specific to the infective bites of Anopheles.
34

Vlastnosti slinných proteinů flebotomů rodu Sergentomyia a Phlebotomus / Comparison and characterization of salivary proteins from Sergentomyia and Phlebotomus sand flies

Polanská, Nikola January 2020 (has links)
Sand flies (Diptera, Phlebotominae) are small biting insects and vectors of Leishmania spp. which cause medically and veterinary important disease - leishmaniasis. During the piercing of the host skin, sand fly females inject saliva to facilitate the blood feeding. The sand fly saliva is composed of many bioactive molecules which were shown to possess anti-inflammatory and anti-haemostatic functions. The saliva affects host's immunity in the bite site and consequently enhances the survival and development of transmitted pathogens. Most of the studies focus on salivary proteins and enzymes of sand flies belonging to Phlebotomus and Lutzomyia genera, while salivary proteins from sand flies of the third genus Sergentomyia were neglected so far. In this thesis we focused on comparison of salivary proteins from two Phlebotomus species, namely Phlebotomus perniciosus and Phlebotomus orientalis, and Sergentomyia schwetzi. These sand fly species differ not only by the ecology and geographical distribution but also by host preferences. Both Phlebotomus species prefer large or medium-size mammals as the bloodmeal source, particularly rabbits, hares and dogs for P. perniciosus and cattle, goats, sheep and humans for P. orientalis. Contrarily, Sergentomyia sand flies are known for preferred feeding on reptiles...
35

Host ligands and oral bacterial adhesion studies on phosphorylated polypeptides and gp-340 in saliva and milk /

Danielsson Niemi, Liza, January 2010 (has links)
Diss. (sammanfattning) Umeå : Umeå universitet, 2010.
36

Interactions entre muqueuse orale, salive et molécules de la flaveur / Interactions between oral mucosa, saliva and flavour compounds

Ployon, Sarah 05 December 2016 (has links)
Le rôle de la salive dans la perception sensorielle est de plus en plus reconnu, notamment par le biais des interactions physico-chimiques pouvant s’établir entre protéines salivaires et constituants alimentaires. Ce travail s’intéresse à la pellicule salivaire, la couche de protéines salivaires ancrées aux cellules épithéliales, et vise à caractériser les interactions pouvant s’établir d’une part entre ces protéines et épithélium oral, et d‘autre part entre ces protéines et les molécules de la flaveur. Pour cela, un modèle in vitro de muqueuse orale a été développé. Une lignée cellulaire stable (TR146/MUC1) a été obtenue par transfection de la lignée cellulaire TR146 de manière à exprimer la mucine membranaire MUC1. Afin de former une pellicule salivaire, les cellules confluentes ont été incubées avec de la salive humaine. La rétention des mucines salivaires MUC5B par les cellules TR146/MUC1 est augmentée par rapport aux TR146, apportant ainsi un argument en faveur de l’implication de MUC1 dans l’ancrage des MUC5B aux cellules épithéliales. Le modèle développé a été appliqué à l’étude des interactions entre la muqueuse orale et les molécules d’arôme et les tanins. L’analyse des coefficients de partage par GC-FID a mis en évidence 1- l’importance de l’hydratation de la muqueuse sur la libération des composés les plus hydrophiles, 2- la capacité des cellules à métaboliser certaines molécules d’arôme, 3- l’absence d’effet de la pellicule sur la libération des molécules d’arôme à l’équilibre. En revanche, l’analyse par PTR-MS a révélé un effet de la muqueuse et de la pellicule sur la cinétique de libération des molécules d’arôme. Les interactions entre les protéines de la pellicule salivaire et les tanins modifient les caractéristiques structurales de la pellicule, en particulier le tapissage des cellules par les MUC5B. Les possibles implications sensorielles, respectivement dans les phénomènes de persistance aromatique et d’astringence, sont discutées. / The role of saliva in food sensory perception is increasingly recognized, especially through physicochemical interactions occurring between salivary proteins and food components. This work focuses on the mucosal pellicle, a layer of salivary proteins anchored onto epithelial cells, and aims at characterizing interactions that may occur between the proteins of the mucosal pellicle and flavour compounds. For that purpose, an in vitro model of oral mucosa was developed. A stable cell line (TR146/MUC1) was obtaining by transfecting the TR146 cell line in order to express the membrane bound mucin MUC1. In order to form a salivary pellicle, confluent cells were incubated with human saliva. A higher retention of salivary MUC5B by TR146/MUC1 cells was observed compared to TR146 cells, emphasising the involvement of MUC1 in MUC5B anchoring to epithelial cells. The model was applied to the investigation of interactions between the oral mucosa and aroma molecules and tannins. Measurements of partition coefficients by GC-FID revealed 1- the role of hydration of the mucosa on the release of the most hydrophilic compounds, 2- the ability of cells to metabolize some aroma compounds, 3- the absence of effect of the mucosal pellicle itself on aroma release at the thermodynamic equilibrium. Oppositely, analyses by PTR-MS evidenced an effect of the mucosa and of the pellicle on aroma release kinetic. Interactions between proteins of the mucosal pellicle and tannins modified structural characteristics of the pellicle, especially the coating of cells by salivary MUC5B. Sensory relevance for the phenomena of aroma persistence and astringency, respectively, are discussed.
37

Exposition continue aux xéno-hormones à faibles doses chez le rat : effets multi-générationnels de mélanges sur les préférences gustatives, le comportement maternel et le développement / Lifelong exposure to low dose xeno-hormones in rats : multi-generational effects of xeno-hormone mixtures on taste preferences, maternal behavior, and development

Boudalia, Sofiane 04 December 2012 (has links)
Durant la dernière décennie, la problématique de santé liée aux perturbateurs endocriniens (PE) s’est étendue à la toxicité des mélanges. L’objectif de ce travail était de définir les conséquences d’une exposition continue à des cocktails des PE, à des doses faibles et définies comme «non nocives » par les autorités réglementaires. Des mélanges associant la génistéine, la vinclozoline, et le Bisphénol A, ont fait l’objet d’étude intégrative et multi-générationnelle chez le rat qui prend en compte le comportement maternel, le comportement alimentaire et le développement. Nos résultats montrent que ces mélanges peuvent: a) diminuer le comportement maternel, b) modifier les préférences gustatives (sucré, salé), c) affecter le développement dès la période utérine (malformations) jusqu’à l’âge adulte (surpoids), d) perturber le bilan métabolique (femelles) et l’expression par la glande salivaire de gènes codant des protéines impliquées dans la gustation, d’engendrer des effets épigénétiques sur sur la génération F2 non exposée. L’étude in vitro confirme que la Génistéine et/ou la Vinclozoline, introduites durant l’induction de la différenciation adipocytaire affectent le développement des 3T3-L1et leur activité endocrine (leptine; triglycérides), et révèle que la Vinclozoline potentialise l’effet anti-adipogénique de la Génistéine.En conclusion, ce travail montre qu’une exposition à des mélanges de PE peut altérer le comportement et le développement, et prédisposer l’organisme à développer des maladies métaboliques telles que le diabète et l’obésité, mais que les propriétés hormonales de chaque composant ne sont pas prédictives des effets cocktails / During the last decade, the issue of health-related endocrine disruptors (ED) has been extended to the toxicity of mixtures. The objective of this study was to define the effects of lifelong exposure to ED mixtures, at low doses defined as "non-harmful" by the authorities. In this aim, the effects of mixtures combining genistein, vinclozolin and bisphenol A, have been investigated in the rat by using an integrative and multi-generational experimental approach which takes into account maternal behavior, feeding behavior and development. Our results show that these mixtures could: a) reduce maternal behavior, b) change taste preferences (sweet, salty), c) affect the development from the in utero period (birth defects) up to adulthood (body overweight) d) disrupt the metabolic balance (females) and the salivary gland expression of genes encoding proteins involved in gustation, and e) generate epigenetic effects on the unexposed F2 generation.An in vitro study confirms that Genistein and / or Vinclozolin, introduced at the step of the induction of adipocyte differentiation affect the development and endocrine activity (leptin, triglycerides) of 3T3-L1 cells and reveals that Vinclozolin potentiates the anti-adipogenic effect of Genistein. To conclude, this study shows that exposure to PE mixtures could affect behavior and development, and could predispose the body to develop metabolic diseases such as diabetes and obesity, but the own hormonal properties of component could not be used to predict the cocktails toxicity
38

Estudo do Fator Inibitório da Migração de Macrófagos(MIF) em pacientes com carcinoma epidermoide da cavidade bucal / Study of Macrophage Migration Inhibitory Factor (MIF) in patients with oral squamous cell carcinoma

Souza, Mariana Barbosa de 15 April 2014 (has links)
INTRODUÇÃO. A proteína Fator Inibitório da Migração de Macrófagos (MIF) é frequentemente observada com expressão elevada em tecidos tumorais quando comparados aos tecidos equivalentes normais e estudos têm sugerido seu papel como marcador prognóstico de neoplasias malignas, incluindo carcinomas hepatocelular, de ovário, de esôfago e também de cabeça e pescoço. Adicionalmente, alguns de seus mecanismos de ação já demonstrados, como a indução da proliferação e migração celular permitem implicar essa expressão diferencial no desenvolvimento tumoral e, consequentemente, no prognóstico das neoplasias malignas. OBJETIVO. Esse estudo objetivou avaliar o papel diagnóstico e prognóstico da proteína MIF em carcinoma epidermóide da cavidade bucal. METODOLOGIA. O estudo foi composto por 50 pacientes com carcinoma epidermoide da cavidade bucal coletados prospectivamente e 57 casos retrospectivos admitidos nos Serviços de Cirurgia de Cabeça e Pescoço do Hospital Heliópolis e da Faculdade de Medicina da Fundação ABC. As análises foram feitas por meio de imunoistoquímica dos tecidos tumorais e margens epiteliais normais e de ELISA das amostras de soro e saliva, coletadas pré e pós-tratamento cirúrgico, dos pacientes participantes. Os resultados foram correlacionados aos achados clínicos e histopatológicos. RESULTADOS. A expressão da proteína MIF e seu receptor CD74 mostrou-se elevada em tecido tumoral quando comparado ao tecido epitelial livre de neoplasia (p < 0,0001). Associação entre a alta expressão da MIF no tumor e infiltração vascular linfática foi observada (p=0,005) e alta expressão da MIF no epitélio livre de tumor apresentou correlação marginalmente significativa com ocorrência de segundo tumor primário (p=0,072). A expressão positiva do receptor CD74 não apresentou associação com variáveis clínicas ou histopatológicas. A concentração sorológica da proteína MIF apresentou associação inversa com metástase linfonodal (p=0,018) e estádios patológicos avançados (p=0,040) e foi significativamente reduzida após a ressecção do tumor (p=0,001). A concentração da MIF na saliva não apresentou redução significativa após o tratamento cirúrgico, mas foi associada aos estágios pT3 e pT4 (p=0,001) e a estádios patológicos avançados (p=0,032). CONCLUSÕES. A redução significante da concentração da MIF observada no soro dos pacientes após a ressecção cirúrgica do tumor permite sugerir papel potencial dessa proteína como biomarcador para a detecção precoce de recorrência do carcinoma epidermoide da cavidade bucal. A expressão tecidual da proteína MIF e seu receptor CD74 apresentou papel controverso, mas a concentração salivar da proteína MIF parece relacionar-se a um possível papel pró-tumoral em carcinoma epidermoide da cavidade bucal / INTRODUCTION. The Macrophage Migration Inhibitory Factor (MIF) overexpression is frequently observed in tumor tissues compared to normal tissues and some previous studies have suggested its role as a prognostic marker of malignancies, including hepatocellular, ovarian, esophageal and also head and neck carcinoma. Additionally, some of its mechanisms of action, as migration and cell proliferation induction, have been demonstrated, which allow imply a differential expression in tumor progression and therefore in the prognosis of malignant neoplasms. OBJECTIVES. This study aimed to evaluate the role of MIF protein and its receptor CD74 in prognosis and diagnostic of oral squamous cell carcinoma. METHODS. The study consisted of 50 patients with oral squamous cell carcinoma prospectively collected and 57 patients retrospectively collected admitted at the Head and Neck Surgery Service from Heliópolis Hospital and ABC Medical School. The analysis were performed by Imunohistochemistry of tumor and normal tissues and by ELISA of serum and saliva samples collected pre and post-surgical treatment. Results were correlated to clinical and histopathological data. RESULTS. The expression of MIF protein and of its receptor CD74 was higher in OSCC than in normal epithelium (p < 0,0001). Association between overexpression of MIF in tumor tissue and lymphatic vessel invasion was observed (p=0,005) and higher concentration of MIF in normal epithelium showed correlation of marginal significance with second primary tumor occurrence (p=0,072). The positive expression of the receptor CD74 did not presented association with clinical or histopathological variables. Serum MIF concentration presented inverse association with lymph node metastasis (p=0,018) and advanced pathological stage (p=0,040) and it was significantly reduced after the surgery (p=0,001). The salivary MIF concentration was not significantly reduced after the surgery, but it was associated with pT3 and pT4 stages (p=0,001) and advanced pathological findings (p=0,032). CONCLUSIONS. The results showing significant reduction of MIF concentration in post-surgical serum of patients suggest its potential role as a biomarker to early detection of oral squamous cell carcinoma recurrence. The MIF and CD74 expression presented controversial role, but the salivary concentration of MIF seems to develop a possible pro-tumoral role
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Estudo do Fator Inibitório da Migração de Macrófagos(MIF) em pacientes com carcinoma epidermoide da cavidade bucal / Study of Macrophage Migration Inhibitory Factor (MIF) in patients with oral squamous cell carcinoma

Mariana Barbosa de Souza 15 April 2014 (has links)
INTRODUÇÃO. A proteína Fator Inibitório da Migração de Macrófagos (MIF) é frequentemente observada com expressão elevada em tecidos tumorais quando comparados aos tecidos equivalentes normais e estudos têm sugerido seu papel como marcador prognóstico de neoplasias malignas, incluindo carcinomas hepatocelular, de ovário, de esôfago e também de cabeça e pescoço. Adicionalmente, alguns de seus mecanismos de ação já demonstrados, como a indução da proliferação e migração celular permitem implicar essa expressão diferencial no desenvolvimento tumoral e, consequentemente, no prognóstico das neoplasias malignas. OBJETIVO. Esse estudo objetivou avaliar o papel diagnóstico e prognóstico da proteína MIF em carcinoma epidermóide da cavidade bucal. METODOLOGIA. O estudo foi composto por 50 pacientes com carcinoma epidermoide da cavidade bucal coletados prospectivamente e 57 casos retrospectivos admitidos nos Serviços de Cirurgia de Cabeça e Pescoço do Hospital Heliópolis e da Faculdade de Medicina da Fundação ABC. As análises foram feitas por meio de imunoistoquímica dos tecidos tumorais e margens epiteliais normais e de ELISA das amostras de soro e saliva, coletadas pré e pós-tratamento cirúrgico, dos pacientes participantes. Os resultados foram correlacionados aos achados clínicos e histopatológicos. RESULTADOS. A expressão da proteína MIF e seu receptor CD74 mostrou-se elevada em tecido tumoral quando comparado ao tecido epitelial livre de neoplasia (p < 0,0001). Associação entre a alta expressão da MIF no tumor e infiltração vascular linfática foi observada (p=0,005) e alta expressão da MIF no epitélio livre de tumor apresentou correlação marginalmente significativa com ocorrência de segundo tumor primário (p=0,072). A expressão positiva do receptor CD74 não apresentou associação com variáveis clínicas ou histopatológicas. A concentração sorológica da proteína MIF apresentou associação inversa com metástase linfonodal (p=0,018) e estádios patológicos avançados (p=0,040) e foi significativamente reduzida após a ressecção do tumor (p=0,001). A concentração da MIF na saliva não apresentou redução significativa após o tratamento cirúrgico, mas foi associada aos estágios pT3 e pT4 (p=0,001) e a estádios patológicos avançados (p=0,032). CONCLUSÕES. A redução significante da concentração da MIF observada no soro dos pacientes após a ressecção cirúrgica do tumor permite sugerir papel potencial dessa proteína como biomarcador para a detecção precoce de recorrência do carcinoma epidermoide da cavidade bucal. A expressão tecidual da proteína MIF e seu receptor CD74 apresentou papel controverso, mas a concentração salivar da proteína MIF parece relacionar-se a um possível papel pró-tumoral em carcinoma epidermoide da cavidade bucal / INTRODUCTION. The Macrophage Migration Inhibitory Factor (MIF) overexpression is frequently observed in tumor tissues compared to normal tissues and some previous studies have suggested its role as a prognostic marker of malignancies, including hepatocellular, ovarian, esophageal and also head and neck carcinoma. Additionally, some of its mechanisms of action, as migration and cell proliferation induction, have been demonstrated, which allow imply a differential expression in tumor progression and therefore in the prognosis of malignant neoplasms. OBJECTIVES. This study aimed to evaluate the role of MIF protein and its receptor CD74 in prognosis and diagnostic of oral squamous cell carcinoma. METHODS. The study consisted of 50 patients with oral squamous cell carcinoma prospectively collected and 57 patients retrospectively collected admitted at the Head and Neck Surgery Service from Heliópolis Hospital and ABC Medical School. The analysis were performed by Imunohistochemistry of tumor and normal tissues and by ELISA of serum and saliva samples collected pre and post-surgical treatment. Results were correlated to clinical and histopathological data. RESULTS. The expression of MIF protein and of its receptor CD74 was higher in OSCC than in normal epithelium (p < 0,0001). Association between overexpression of MIF in tumor tissue and lymphatic vessel invasion was observed (p=0,005) and higher concentration of MIF in normal epithelium showed correlation of marginal significance with second primary tumor occurrence (p=0,072). The positive expression of the receptor CD74 did not presented association with clinical or histopathological variables. Serum MIF concentration presented inverse association with lymph node metastasis (p=0,018) and advanced pathological stage (p=0,040) and it was significantly reduced after the surgery (p=0,001). The salivary MIF concentration was not significantly reduced after the surgery, but it was associated with pT3 and pT4 stages (p=0,001) and advanced pathological findings (p=0,032). CONCLUSIONS. The results showing significant reduction of MIF concentration in post-surgical serum of patients suggest its potential role as a biomarker to early detection of oral squamous cell carcinoma recurrence. The MIF and CD74 expression presented controversial role, but the salivary concentration of MIF seems to develop a possible pro-tumoral role

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