Neste estudo, foi determinado o dano celular em linfócitos periféricos após exposição ao 153Sm-EDTMP (Samário-153 etilenodiaminotetrametilenofosfonato) por meio da técnica de análise de micronúcleos e coloração diferencial. O 153Sm-EDTMP é um radiofármaco utilizado para alívio da dor em pacientes com metástase óssea. A análise da freqüência de micronúcleos em amostras sangüíneas de pacientes obtidas uma hora após a administração endovenosa do radiofármaco (41 MBq/kg) mostrou que não houve diferença estatística em relação aos valores basais em células binucleadas. Porém, a análise da distribuição do dano em células mononucleadas mostrou que os pacientes sem tratamento radioterápico prévio apresentaram um aumento significativo na freqüência de células com um micronúcleo e aqueles com tratamento radioterápico prévio, nas células com dois ou mais micronúcleos. Os experimentos in vitro realizados com exposição de sangue total a três concentrações radioativas de 153Sm-EDTMP (0,370; 0,555 e 1,110 MBq/mL) por uma hora mostraram um aumento na freqüência de micronúcleos e de células necróticas e apoptóticas com o aumento da dose de radiação. Foram construídas curvas dose-resposta para os indivíduos sadios e para os pacientes com metástases óssea sem prévio tratamento radioterápico. A comparação das curvas mostrou que os pacientes apresentaram uma radiossensibilidade mais alta que os indivíduos sadios tanto quanto a porcentagem de células com micronúcleos como de células mortas (necróticas e apoptóticas). / In this study the cellular damage in peripheral lymphocytes after exposure to 153Sm-EDTMP (Samarium-153 ethylenediaminetetrametylenephosphonate) was determined using the technique of micronuclei analysis and differential coloration. 153Sm- EDTMP is a radiopharmaceutical used for pain relief in patients with bone metastases. The analysis of the frequency of micronuclei in patient blood samples obtained one hour after endovenous administration of radiopharmaceutical (41 MBq/kg) showed no statistical difference in relation to basal values in binucleated cells. However the analysis of damage distribution in mononucleated cells, showed that the patients without previous radiotherapic treatment presented a significant increase in the frequency of cells with one micronucleus and in those who had taken previous radiotherapic treatment, in cells with two or more micronuclei. The in vitro experiments conducted with the exposition of total blood to three radiation concentrations of 153Sm-EDTMP (0.370, 0.555 and 1.110 MBq/mL) during one hour showed an increase in the frequency of micronuclei and necrotic and apoptotic cells with increasing radiation dose. Dose-response curves for healthy donors and patients with bone metastasis without previous radiotherapic treatment were constructed. The comparison of the curves showed that patients presented higher radiosensitivity, either micronuclei or dead cell (necrotic or apoptotic) percentages, than healthy donors.

A new lattice-Boltzmann finite-element method is used to simulate large numbers of deformable red blood cells and platelets in suspension for the investigation of stress-mediated platelet-deposition mechanisms in blood. The coupled lattice-Boltzmann finite-element method provides the novel ability to simulate hundreds of realistic and deformable red blood cells and produce continuum-scale physics at physiologic hematocrit and low arterial-shear rates. The new method is developed and shown to produce single red blood cell deformation consistent with experimental results in flow chambers. Simulations of 77 to 216 cells in unbounded shear flow produce bulk and micro-rheological behavior consistent with experimental results in viscometers and tubes, including shear-thinning behavior at various shear rates. Investigation of the local stress environment in blood indicates that, although the majority of platelets experience a time-averaged shear stress equal to the suspension stress, 25% of platelets experience a localized shear stress greater than twice the suspension stress. The lattice-Boltzmann finite-element method developed in this work has been shown capable of investigating the fundamental gap between cell-level processes and continuum-level function. The complex stress environment in whole blood has been described for simple shear flow and the methodology may be extended to more complex flow geometries and incorporate platelet-adhesion models for adhesion studies. Thus, this research fits into the greater objective of prediction and control of platelet deposition in clinical and engineering applications. Furthermore, the ability to bridge the gap between cell-level processes and continuum-level function is useful in other important cardiovascular areas including leukocyte adhesion, platelet aggregate embolization, and artheriogenesis.

Plusieurs études ont démontré une association entre l’agrégation érythrocytaire du milieu sanguin et plusieurs anomalies hémorhéologiques. Cette agrégation peut être quantifiée à l'aide du coefficient de rétrodiffusion ultrasonore. Pour décrire l’interaction entre l'onde ultrasonore et les tissus biologiques, on se sert de modèles. Ainsi, le modèle de facteur de structure (MFS) est utilisé pour évaluer le coefficient de rétrodiffusion des globules rouges agrégés. Toutefois, ce modèle numérique ne permet pas des mesures en temps réel du niveau d’agrégation et n'informe pas sur la structure du milieu sanguin comme par exemple la taille de l’agrégat. Pour pallier à ces difficultés, nous proposons un modèle où la théorie du milieu effectif est combinée au modèle de facteur de structure. Tout en permettant une mesure en temps réel de l’agrégation, ce modèle nommé TMEMFS fournit en plus deux indices structuraux de l’agrégation: le rayon de l’agrégat ainsi que sa compacité. Par le biais de simulations numériques en 3D, on a comparé le coefficient de rétrodiffusion suivant les modèles MFS et TMEMFS. Ceci dans le but de vérifier que dans la solution du problème direct, les propriétés acoustiques des globules rouges et les propriétés structurales du milieu agrégeant correspondaient à la réalité. Pour simuler des agrégats de globules rouges, une disposition hexagonale compacte a été utilisée. Les effets du rayon et de la compacité sur le coefficient de rétrodiffusion ont été étudiés. Basé sur la microstructure sanguine considérée, les résultats obtenus avec le modèle TMEMFS sont semblables à ceux du modèle MFS. Ce travail constitue un support théorique pour une mesure quantitative in vivo de l’agrégation érythrocytaire à des fins diagnostics. / Many studies have reported that an enhanced level of red blood cell aggregation is associated with the presence of hemorheological disorders. Pathological aggregation has been characterized by quantitative ultrasound based on the backscattering coefficient. In order to describe the interaction between the incident ultrasound and the interrogated biological tissues, mathematical models are used. Mathematical modeling is known to be the optimal way to describe the interaction occurring between ultrasound and tissues at the cellular level. The structure factor model (SFM), considered as the exact scattering model has been developed to predict the backscattering coefficient from blood. However, the numerical SFM cannot be applied in real time for practical measurements and does not provide aggregate size to assess the level of aggregation. Therefore, we come up with a new model based on the effective medium theory in order to tackle this difficulty. The effective medium theory combined with the structure factor model (EMTSFM) can be applied in real time and contrary to the SFM provides two indices of the aggregate state in vivo: aggregate size and compactness. Based on a 3D simulation study, the backscattering coefficients (BSCs) predicted by the effective medium theory combined with the Structure Factor Model (EMTSFM) are compared to the BSCs computed with SFM. Our aim here is to assess the accuracy of the EMTSFM against the SFM by comparing their BSC in the framework of a forward problem, i.e., the calculation of the BSC from the known acoustic and structure aggregate parameters. This was done in order to validate the proposed model. To simulate aggregates, RBCs are stacked following a hexagonal close packing scheme. The influences of the aggregate radius and compactness on the BSC are studied as well. The results showed good agreement between the SFM and the EMTSFM based on our simulated microstructure of RBC aggregates. Our work provides thus the theoretical background to assess locally the aggregation level for diagnosis purposes. / Le travail a été réalisé en collaboration avec le laboratoire de mécanique acoustique de Marseille, France. Les simulations ont été menées avec les langages Matlab et C. Ce projet s'inscrit dans le champ de recherche dénommé caractérisation tissulaire par ultrasons.

A contagem de células vermelhas do sangue desempenha um papel importante no diagnóstico de animais silvestres e domésticos. Apesar da existência de muitas tecnologias em diferentes contadores automatizados para análise de sangue, quando se trata do sangue de animais silvestres ainda é difícil encontrar uma solução simples e economicamente viável para múltiplas espécies. O objetivo deste estudo é desenvolver um contador automático de células vermelhas. Amostras de sangue (1 jaguatirica - Leopardus pardalis, 1 macaco - Cebus apella, 1 quati - Nasua nasua, 62 cães - Canis familiaris e 5 cavalos - Equus caballus) foram analisadas usando três métodos: 1-contagem manual, 2-contagem automática por imagem e 3-contagem semiautomática por imagem; as amostras de cães e cavalos foram analisadas por um quarto método: 4-contagem automática por impedância. As contagens dos métodos 2 e 3 foram obtidas usando o contador de células vermelhas proposto. Os resultados foram comparados usando a correlação de Pearson e gráficos com diferentes métodos como valor de referência. As contagens dos métodos 1, 2 e 3 correlacionaram muito bem com as contagens do método 4 (r ≥ 0.94). As contagens produzidas pelo método 2 apresentaram alta correlação com o método 3 (r = 0.998). Os resultados indicam que o contador proposto pode ser usado como um método de contagem automática ou semiautomática em clínicas que usam o método manual para contagem de células vermelhas do sangue de animais. / A RBC count plays an important role in the diagnostic of wild and domestic animals. Despite the many technologies available in different automated hematology analyzers, when it comes to blood of wild animals it is still difficult to find an easy and affordable solution for multiple species. This study aims to develop an automatic red blood cell counter. Blood samples (1 ocelot - Leopardus pardalis, 1 monkey - Cebus apella, 1 coati - Nasua nasua, 62 dogs - Canis familiaris and 5 horses - Equus caballus) were analyzed using three methods: 1-manual count, 2automatic count by image and 3-semi-automatic count by image; blood from dogs and horses were also analyzed by a fourth method: 4-automatic count by impedance. The counts of methods 2 and 3 were produced by the proposed red blood cell counter. Results were compared using Pearson’s correlation and plots with different methods as the criterion standard. RBC counts of methods 1, 2 and 3 correlated very well with those on the method 4 (r ≥ 0.94). RBC counts produced by method 2 were highly correlated with method 3 (r = 0.998). The results indicate that the proposed method can be used as an automatic or semi-automatic counting method in clinics that are currently using the manual method for RBC assessment.

L'objectif de cette thèse est d'améliorer la compréhension des phénomènes jouant un rôle dans la mesure effectuée dans un analyseur sanguin, en particulier le comptage et la mesure de volumétrie d'une population de globules rouges reposant sur l'effet Coulter. Des simulations numériques sont effectuées dans le but de prédire la dynamique des globules rouges dans les zones de mesure et pour reproduire la mesure électrique associée, servant au comptage et à la volumétrie des cellules. Ces simulations sont effectuées à l'intérieur de configurations industrielles d'analyseur sanguin, en utilisant un outil numérique développé à l'IMAG, le solveur YALES2BIO. En utilisant la méthode des frontières immergées avec suivi de front, un modèle de particule déformable est introduit, celui-ci prend en compte le contraste de viscosité ainsi que les effets mécaniques de la courbure et de l'élasticité sur la membrane. Le solveur est validé grâce à de nombreux cas tests parcourant différents régimes et effets physiques. L'écoulement fluide dans cette géométrie d'analyseur sanguin est caractérisée par un fort gradient de vitesse axial dans la direction de l'écoulement, impliquant la présence d'un écoulement extensionnel au niveau du micro-orifice, là où a lieu la mesure. La dynamique des globules rouges est étudiée par des simulations numériques pour différentes conditions initiales, telles que sa position ou son orientation. Il est observé que les globules rouges vont se réorienter selon l'axe principal de l'analyseur sanguin dans tous les cas. Pour comprendre le phénomène, des modèles analytiques sont adaptés au cas des écoulements extensionnels et reproduisent correctement les tendances de réorientation.Cette thèse présente également la reproduction de la mesure électrique utilisée pour le comptage et la mesure de la distribution des volumes de globules rouges. De nombreuses simulations de la dynamique des globules rouges sont effectuées et utilisées pour générer l'impulsion électrique correspondant au passage du globule rouge dans le micro-orifice. Les amplitudes d'impulsions électriques résultantes permettent la caractérisation de la réponse électrique en fonction des paramètres initiaux de la simulation par une approche statistique. Un algorithme de Monte-Carlo est utilisé pour la quantification des erreurs de mesure liées à l'orientation et la position des globules rouges dans le micro-orifice. Ceci permet la génération d'une distribution de volume mesurée pour une population de globules rouges bien définie et la caractérisation des erreurs de mesure associées. / The aim of this thesis is to improve the understanding of the phenomena involved in the measurement performed in a blood analyzer, namely the counting and sizing of red blood cells based on the Coulter effect. Numerical simulations are performed to predict the dynamics of red blood cells in the measurement regions, and to reproduce the associated electrical measurement used to count and size the cells. These numerical simulations are performed in industrial configurations using a numerical tool developed at IMAG, the YALES2BIO solver. Using the Front-Tracking Immersed Boundary Method, a deformable particle model for the red blood cell is introduced which takes the viscosity contrast as well as the mechanical effects of the curvature and elasticity on the membrane into account. The solver is validated against several test cases spreading over a large range of regimes and physical effects.The velocity field in the blood analyzer geometry is found to consist of an intense axial velocity gradient in the direction of the flow, resulting in a extensional flow at the micro-orifice, where the measurement is performed. The dynamics of the red blood cells is studied with numerical simulations with different initial conditions, such as its position or orientation. They are found to reorient along the main axis of the blood analyzer in all cases. In order to understand the phenomenon, analytical models are adapted to the case of extensional flows and are found to reproduce the observed trends.This thesis also presents the reproduction of the electrical measurement used to count red blood cells and measure their volume distribution. Numerous dynamics simulations are performed and used to generate the electrical pulse corresponding to the passage of a red blood cell inside the micro-orifice. The resulting electrical pulse amplitudes are used to characterize the electrical response depending on the initial parameters of the simulation by means of a statistical approach. A Monte-Carlo algorithm helps quantifying the errors on the measurement of cell depending on its orientation and position inside the micro-orifice. This allows the generation of a measured volume distribution of a well defined red blood cell population and the characterization of the associated measurement errors.

Cette thèse traite plusieurs aspects scientifiques inhérents à la simulation numérique de problèmes d'interaction fluide-structure impliquant de fines membranes déformables. Deux cas spécifiques relatifs à la biomécanique cardiovasculaire sont considérés : l'interaction de l'écoulement sanguin avec la valve aortique (qui se produit à l'échelle macroscopique), et l'interaction de la membrane des globules rouges avec ses fluides interne et externe (qui se produit à l'échelle microscopique). Dans les deux cas, le couplage fluide-structure est géré par l'intermédiaire d'un formalisme de frontières immergées, en représentant la membrane par un maillage Lagrangien se mouvant au travers d'un maillage fluide Eulérien. Lorsque l'on traite la dynamique des globules rouges, la membrane est considérée comme étant une structure sans masse et infiniment fine. La première question à laquelle on s'intéresse dans cette thèse est la manière de modéliser la microstructure complexe de la membrane des globules rouges. Un moyen possible pour caractériser un modèle de membrane adapté est de simuler l'expérience des pinces optiques, qui consiste en une configuration expérimentale bien contrôlée qui permet d'étudier la mécanique individuelle d'un globule rouge isolé dans une large gamme de déformations. Plusieurs modèles pertinents sont identifiés, mais les caractéristiques de déformation mesurées durant l'expérience des pinces optiques se révèlent n'être pas assez sélectives pour être utilisées dans un contexte de validation. Des mesures de déformation additionnelles sont proposées, qui pourraient permettre une meilleure caractérisation de la mécanique de la membrane des globules rouges. En ce qui concerne les configurations macroscopiques, une méthode numérique innovante est proposée afin de gérer des simulations numériques de membranes 3D continues, en conservant le formalisme de frontières immergées. Dans cette méthode, appelée méthode des frontières immergées épaisses, la membrane a une épaisseur finie. La précision et la robustesse de la méthode sont démontrées par l'intermédiaire d'une variété de cas tests bien choisis. La méthode proposée est ensuite appliquée à un problème d'interaction fluide-structure réaliste, à savoir l'interaction d'un écoulement (sanguin) pulsé avec une valve aortique biomimétique. Une étude combinée expérimentale et numérique est menée, montrant que la méthode est capable de capturer la dynamique globale de la valve, ainsi que les principales caractéristiques de l'écoulement en aval de la valve. Tous les développements ont été effectués dans le solveur YALES2BIO (http://www.math.univ-montp2.fr/~yales2bio/) développé à l'IMAG, qui est donc disponible pour toutes autres améliorations, validations et études applicatives. / This thesis deals with several scientific aspects inherent to the numerical simulation of fluid-structure interaction problems involving thin deformable membranes. Two specific cases relevant to cardiovascular biomechanics are considered: the interaction of the blood flow with the aortic valve (which occurs at the macroscopic scale), and the interaction of the red blood cells membrane with its inner and outer fluids (which occurs at the microscopic scale). In both cases, the fluid-structure interaction coupling is handled using an immersed boundary formalism, representing the membrane by a Lagrangian mesh moving through an Eulerian fluid mesh.When dealing with red blood cells dynamics, the membrane is considered to be an infinitely thin and massless structure. The first question which is addressed in the present thesis work is how to model the complex microstructure of the red blood cells membrane. A possible way to characterize a suitable membrane model is to simulate the optical tweezers experiment, which is a well-controlled experimental configuration enabling to study the individual mechanics of an isolated red blood cell in a large range of deformation. Some relevant membrane models are identified, but the deformation characteristics measured during the optical tweezers experiment reveal to be not selective enough to be used in a validation context. Additional deformation measurements are proposed, which could allow a better characterization of the red blood cell membrane mechanics.Regarding the macroscopic configurations, an innovative numerical method is proposed to handle numerical simulations of 3D continuum membranes, still within the immersed boundary formalism. In this method, called immersed thick boundary method, the membrane has a finite thickness. The accuracy and robustness of the method are demonstrated through a variety of well-chosen test cases. Then, the proposed method is applied to a realistic fluid-structure interaction problem, namely the interaction of a pulsatile (blood) flow with a biomimetic aortic valve. A combined experimental and numerical study is led, showing that the method is able to capture the global dynamics of the valve, as well as the main features of the flow downstream of the valve.All the developments were performed within the YALES2BIO solver (http://www.math.univ-montp2.fr/~yales2bio/) developed at IMAG, which is thus available for further improvements, validations and applicative studies.

No description available.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Evidências crescentes têm demonstrado que o exercício prejudica a estrutura da membrana eritrocitária, como consequência do aumento do estresse físico e químico. O óxido nítrico (NO) derivado dos eritrócitos afeta a fluidez da membrana e a sua biodisponibilidade depende do equilíbrio entre a sua síntese e eliminação por espécies reativas de oxigênio. Nós investigamos se o exercício realizado em diferentes intensidades afetaria biodisponibilidade do NO eritrocitário e se levaria a um quadro de estresse oxidativo. Dez homens (26 4 anos, VO2pico 44,1 4,3 mL.kg-1.min-1) realizaram um teste cardiopulmonar máximo em esteira e um teste de exercício submáximo a 70% VO2pico durante 30 min. O sangue foi coletado em repouso e imediatamente após os exercícios para isolamento dos eritrócitos. O exercício máximo aumentou a contagem de eritrócitos, hemoglobina e hematócrito, sem levar a qualquer alteração na massa corporal que pudesse sugerir hemoconcentração devido a uma redução do volume plasmático. Observou-se uma diminuição do influxo de L-arginina depois do teste submáximo, mas não no teste máximo. No entanto, a atividade da óxido nítrico sintase, ou seja, a produção de NO, foi aumentada após o teste máximo. Os níveis de GMPc não se alteraram após ambos os teste de exercício. Em relação aos biomarcadores de estresse oxidativo, o exercício submáximo reduziu a oxidação proteica e aumentou a atividade da catalase e a expressão da glutationa peroxidase, enquanto que o exercício máximo levou a uma maior peroxidação lipídica e diminuição da atividade da SOD. Nem a atividade glutationa peroxidase ou a expressão NADPH oxidase foram afetadas pelo exercício. Estes resultados sugerem que o exercício induziu alterações no estresse oxidativo de eritrócitos, que parecem estar mais associadas com a intensidade do que a duração do execicio. Além disso, nas intensidades recomendadas para a promoção da saúde, o exercício mostrou ser protetor, aumentando a atividade e a expressão de enzimas antioxidantes importantes e reduzindo os danos oxidativos. / Growing evidence has shown that exercise impairs erythrocyte membrane structure as a consequence of increased physical and chemical stress. Erythrocyte-derived nitric oxide (NO) affects membrane fluidity, and its bioavailiability depends on the balance between its synthesis and scavenging by reactive oxygen species. Here, we investigated whether aerobic exercise performed at different intensities would affect erythrocyte NO bioavailability and oxidative stress. Ten men (26 4 years old, VO2peak 44.1 4.3 mL.kg-1.min-1) performed a treadmill maximal cardiopulmonary exercise test, and a submaximal exercise at 70% VO2peak during 30 min. Blood was collected at rest and immediately after exercises for erythrocytes isolation. Maximal exercise increased erythrocytes count, haemoglobin and haematocrit levels, without any change in body mass that could suggest haemoconcentration due to a plasma volume reduction. It was observed a decrease in L-arginine influx after moderate, but not maximal exercise. Yet, nitric oxide synthase activity, and thus, NO production, was increased after maximal exercise. Cyclic GMP levels did not change after both exercise bouts. In relation to biomarkers of oxidative stress, moderate exercise reduced protein oxidation, and increased catalase activity and glutathione peroxidise expression; whereas maximal exercise led to greater lipid peroxidation, and diminished SOD activity. Neither glutathione peroxidase activity nor NADPH expression were affected by exercise. These findings suggest that exercise induced changes in erythrocyte oxidative stress are more associated with intensity than duration. Furthermore, at intensities recommended for health promotion, exercise was shown to be protective, increasing the activity and expression of important antioxidant enzymes and reducing oxidative damage.

Made available in DSpace on 2014-12-17T14:13:35Z (GMT). No. of bitstreams: 1 BernardoMR.pdf: 260986 bytes, checksum: 17a4b2567679fec24073be98451b0953 (MD5) Previous issue date: 2008-03-25 / Blood constituents labelled with technetium-99m (99mTc) has been used with radiobiocomplexes in several procedures in nuclear medicine. Some natural and sintetic drugs are capable to interfere on the labeling of blood constituents with 99mTc, on the morphology of red blood cells (RBC) and on the biodistribution of radiobiocomplexes. The aim of this study was evaluate the effect of an extract of Passiflora edulis f. flavicarpa on the labeling of blood constituints with 99mTc, on the morphology of RBC and on the biodistribution of the radiopharmaceutical sodium perthecnetate in Wistar rats. On the in vitro studies the Passiflora edulis f. flavicarpa decreased significantly (p<0.05) the %ATI on plasma proteins and on the in vitro morhology of RBC, the passion fruit peel flour altered the shape and the perimeter/?rea ratio. On the in vivo estudies the extract did not altered the %ATI in blood constituents, and did not altered the shape of RBC. Although, on the biodistribution of the radiobiocomplex sodium perthecnetate (Na99mTcO4) this extract decreased significantly (p<0.05) the uptake in duodenum, spleen, p?ncreas and blood, and increased the uptake in stomach. It can be suggested that the effects presented by this extract could be a result of some substances contained in this extract that could alter the binding of 99mTc to plasma proteins, the morphology of RBC and the biodistribution of the radiobiocomplex sodium perthecnetate. This study was multidisciplinary experimental research. It was developed with the contribution of different Departments and Services of the Hospital Universit?rio Pedro Ernesto of the Universidade Estadual do Rio de Janeiro / Constituintes sang??neos marcados com tecn?cio-99m (99mTc) t?m sido utilizadas com radiobiocomplexos em procedimentos da Medicina Nuclear. Determinadas drogas naturais ou sint?ticas s?o capazes de interferir na marca??o de estruturas sang??neas com 99mTc, na morfometria de hem?cias e na biodisponibilidade de radiobiocomplexos. O objetivo deste estudo foi avaliar o efeito de um extrato de farinha da casca do maracuj? (Passiflora edulis f. flavicarpa) na marca??o de constituintes sangu?neos com 99mTc, na morfologia de hem?cias marcadas com 99mTc e na biodisponibilidade do radiobiocomplexo pertecnetato de s?dio. Nos estudos in vitro, o extrato foi capaz de diminuir significativamente (p<0,05) a fixa??o do 99mTc nas prote?nas plasm?ticas e tamb?m alterar a forma e a rela??o per?metro/?rea de hem?cias. Nos estudos in vivo, o extrato de farinha da casca de maracuj? n?o alterou a marca??o dos constituintes sangu?neos com 99mTc, assim como a forma de hem?cias marcadas com 99mTc. No estudo da biodisponibilidade do radiobiocomplexo pertecnetato de s?dio (Na99mTcO4), o extrato estudado aumentou significativamente (p<0,05) a capta??o no duodeno e ba?o, e diminuiu a capta??o do Na99mTcO4 no p?ncreas, est?mago e sangue. Os efeitos apresentados por este extrato podem ser derivados de subst?ncias presentes no extrato, que poderiam alterar a liga??o do 99mTc ?s prote?nas plasm?ticas, induzir altera??es morfol?gicas nas hem?cias e/ou a biodisponibilidade do radiobiocomplexo pertecnetato de s?dio.. Este trabalho foi desenvolvido em diferentes Departamentos e Servi?os da ?rea biom?dica do Hospital Universit?rio Pedro Ernesto, UERJ, atestando o car?ter multidisciplinar da pesquisa

Made available in DSpace on 2014-12-17T14:13:46Z (GMT). No. of bitstreams: 1 Raquel Terra Agostinho_DISSERT.pdf: 212655 bytes, checksum: afa93fe07c8ba1db5dc83395a1dc586d (MD5) Previous issue date: 2009-09-29 / Clinical evaluations have been made possible with radiobiocomplexes marked with tecnecium-99m (99mTc). Natural or synthetic drugs are able to interfere in the marking of blood structures with 99m Tc. Also, the toxicity of several natural products has been described. The aim of this study was evaluating the effect of an extract of Ganoderma lucidum (Reishi) in the marking of blood constituents with 98m Tc and in the survival of Escherichia coli. Blood samples from Wistar rats were treated with reishi extract. Radiomarking procedure was performed. Samples of plasma (P), blood cells (CS), and insoluble (FI) and soluble (FS) fractions of P and CS were separated and the radioactivity was counted to determine radioactivity percentages (%ATI). Escherichia coli AB1157 cultures were treated with stannous chloride in the presence and absence of the reishi extract. Blood samples and bacterial cultures treated with NaCl 0.9% were used as controls. Data indicated that the reishi extract has significantly altered (p<0,05) the %ATI of P, CS, FI-P, FS-P, FI-CS e FS-CS, as well as it has increased survival of bacterial cultures treated with stannous chloride. Our results suggest that the Reishi extract would be able to present a redox/ chelant action by altering blood constituent marking with 99mTc and by protecting bacterial cultures against stannous chloride-induced oxydating lesions. The study had a multidisciplinary character, with the participation of the following areas of knowledge: Biophysics, Radiobiology, Botanics, Phytotherapy, and Hematology / Avalia??es cl?nicas t?m sido poss?veis com radiobiocomplexos marcados com tecn?cio-99m (99mTc). Drogas naturais ou sint?ticas s?o capazes de interferir na marca??o de estruturas sangu?neas com 99mTc, e tamb?m tem sido descrita a toxicidade de v?rios produtos naturais. O objetivo deste estudo foi avaliar o efeito de um extrato de Ganoderma lucidum (Reishi) na marca??o de constituintes sangu?neos sang??neas com 99mTc e na sobreviv?ncia de Escherichia coli. Amostras de sangue de ratos Wistar foram tratadas com extrato de reishi. O procedimento de radiomarca??o foi realizado. Amostras de plasma (P), c?lulas sang??neas (CS) e fra??es insol?vel (FI) e sol?vel (FS) de P e CS foram separadas e a radioatividade foi contada para determina??o das porcentagens de radioatividade (%ATI).Culturas de Escherichia coli AB1157 foram tratadas com cloreto estanoso na presen?a e aus?ncia do extrato de reishi. Amostras de sangue e culturas bacterianas tratadas com NaCl 0.9% foram usadas como controles. Dados indicaram que o extrato de reishi alterou significativamente (p<0,05) a %ATI de P, CS, FI-P, FS-P, FI-CS e FS-CS, bem como, aumentou a sobreviv?ncia de culturas bacterianas tratadas com cloreto estanoso. Nossos resultados sugerem que o extrato de Reishi poderia apresentar a??o redox/quelante alterando a marca??o de constituintes sang??neos com 99mTc e protegendo culturas bacterianas contra les?es oxidativas induzidas pelo cloreto estanoso. O estudo teve car?ter multidisciplinar com a participa??o das seguintes ?reas do conhecimento: Biof?sica, Radiobiologia, Bot?nica, Fitoterapia e Hematologia