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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Neonatal testosterone treatment affects the paw elevation of the Mongolian gerbil (Meriones unguiculatus)

Robertson, Rohan 08 1900 (has links)
<p> The present thesis reports an experiment that investigated the phenomenon of asymmetric paw elevation in the tripedal stance of the Mongolian gerbil, and tested the Geschwind-Galaburda extra-genetic theory of human handedness. Neonate gerbils of both sexes were injected with testosterone propionate during the "critical" period of brain development. They were then assessed for asymmetry in eye opening, for anogenital distance, and for paw elevation and scent marking before and after puberty. Eye opening asymmetry was not affected by treatment. Paw elevation was affected by treatment, with treated gerbils of both sexes displaying more right elevations before and after puberty than untreated gerbils. Control females displayed systematic patterns in paw elevation before and after puberty. Adult gerbils in all conditions displayed more consistency in paw elevation than young gerbils. Anogenital distance was increased with treatment, but only in the females. Adult scent marking behavior was marginally reduced with treatment, but only in the males. Results are interpreted within the Geschwind-Galaburda theory of handedness, and the hormonal basis of paw elevation is discussed. </p> / Thesis / Master of Science (MSc)
2

Murine Metapodophalangeal Sesamoid Bone Mineralization: A Light and Electron Microscopy Study

Doherty, Alison R. H. 17 November 2007 (has links)
No description available.
3

Cálculos ab initio de interações entre Cd e bases nitrogenadas do DNA / Ab Initio calculations of interactions betweeen Cd and nitrogenous bases o DNA

Petersen, Philippe Alexandre Divina 11 May 2011 (has links)
As interações hiperfinas são uma ótima ferramenta para estudar um sítio específico e obter informações importantes sobre o sistema. No presente trabalho analisamos de forma teórica as propriedades eletrônicas, estruturais e hiper nas do Cádmio (Cd) ligado às bases nitrogenadas do DNA. A motivação surgiu da colaboração com o grupo do prof. Artur W. Carbonari do Instituto de Pesquisas Energéticas e Nucleares (IPEN) e que tem como objetivo investigar o DNA e anticorpos de linhagens de camundongos infectados pela cepa Y de Trypanosoma cruzi, protozoário causador da doença de Chagas. A técnica Time Differential Perturbed Angular Correlation (TDPAC) foi utilizada para obter as medidas das interações hiperfinas do DNA. O núcleo de prova das medidas foi o 111Cd. Utilizamos uma abordagem quântica ab initio all-electron, dentro da Teoria do Funcional da Densidade (DFT), através do código computacional CP-PAW que combina o método Projector Augmented Wave (PAW) e a dinâmica molecular quântica de Car-Parrinello (CPMD). Ressaltamos que, até o presente momento, nenhum estudo com esta abordagem teórica e com este código computacional foi realizado para investigar as propriedades hiper nas do Cd ligado as bases nitrogenadas do DNA. / The Hyperfine interactions are good tools to study speci c sites and obtain important information about a given system. In this work we study electronic, structural and hyper ne properties of the Cadmium (Cd) coordinated to the DNA nitrogenous bases. The motivation for this study arose from a collaboration with the group of prof. Arthur W. Carbonari at the Institute of Energy and Nuclear Research (IPEN), which aims to investigate DNA and antibodies to strains of mice infected with the Trypanosoma cruzi, the protozoan that causes Chagas disease. The Time Differential Perturbed Angular Correlation (TDPAC) technique was used to obtain hypefine interactions measurements at a Cd probe bonded to DNA. We use ab initio all-electron calculations, within the Density Functional Theory (DFT) and we use the computer code CP-PAW that combines the Projector Augmented Wave (PAW) method and the Car-Parrinello (CP) quantum molecular dynamics approach to. We emphasize that, until now, no study with this theorectical approach and with this computer code was conducted to investigate the hyper ne properties of the Cd binding to the DNA bases.
4

Estudo das propriedades mecânicas em união de aços dissimilares soldadas pelo processo a plasma e a laser / Study of the mechanical properties in joints of dissimilar steels welded by the plasma and laser process

Silva, Deivid Ferreira da [UNESP] 27 July 2018 (has links)
Submitted by Deivid Ferreira Da Silva (deividferreira@yahoo.com.br) on 2018-10-03T04:44:50Z No. of bitstreams: 1 Doutorado Deivid Ferreira da Silva.pdf: 10141229 bytes, checksum: 7567992adf30e9e3b21fc1984e079772 (MD5) / Approved for entry into archive by Pamella Benevides Gonçalves null (pamella@feg.unesp.br) on 2018-10-05T12:48:01Z (GMT) No. of bitstreams: 1 silva_df_dr_guara.pdf: 10141229 bytes, checksum: 7567992adf30e9e3b21fc1984e079772 (MD5) / Made available in DSpace on 2018-10-05T12:48:01Z (GMT). No. of bitstreams: 1 silva_df_dr_guara.pdf: 10141229 bytes, checksum: 7567992adf30e9e3b21fc1984e079772 (MD5) Previous issue date: 2018-07-27 / O objetivo deste trabalho é avaliar e comparar a resistência mecânica da união de aços dissimilares, o aço Maraging 300 com o aço 300M-ESR pelos processos de soldagens autógenas a Plasma (Plasma Arc Welding – PAW) e a Laser (Laser Beam Welding – LBW). As juntas foram submetidas à avaliação da resistência mecânica através de ensaios de tração e de dureza Vickers (HV) no cordão de solda e zona termicamente afetada. Foram também realizadas análises químicas e metalográficas das juntas soldadas, correlacionando a microestrutura com as propriedades observadas. Em ambos os processos foram aplicados tratamentos térmicos antes e após as soldagens, com o objetivo de endurecer os materiais e procurando aproximar a dureza de ambos os aços e da zona fundida (ZF) e zona termicamente afetada pelo calor (ZTA). Foram realizados vários testes com tempos e temperaturas para se definir quais eram os melhores tratamentos térmicos adotados para a equalização das propriedades mecânicas. Os tratamentos térmicos aplicados após a solda mostraram-se convenientes para o nivelamento dos valores das durezas, somente exibindo poucas perdas nas ZTAs dos aços Maraging. Com a aplicação destes tratamentos também foi possível notar uma equalização nas resistências à tração, em torno de 1300 MPa e aumentos consideráveis das mesmas, comparado com a mesma condição sem tratamento. As soldas mostraram-se eficientes para a união das chapas, porém, em algumas situações da soldagem a Laser, apresentou pequenas falhas, presença de poros, nos cordões das soldas, com isso contribuindo para a diminuição do limite da resistência à tração. / The objective of this work is to evaluate and compare the mechanical strength of welded joints made of the dissimilar steels such as Maraging 300 steel with 300M-ESR steel by the autogenous Plasma Arc Welding (PAW) and Laser welding process (LBW). The joints were submitted to the mechanical strength evaluation by tensile test and hardness Vickers (HV) at the weld bead and thermally affected zone. Chemical analysis and metallographic analysis of the welded joints were also performed, correlating the microstructure observed with the properties. In both processes, heat treatments were applied before and after welding, with the objective of at harden the materials and seeking to approximate the hardness of both steels and the fusion zone and heat affected zone. Several tests were carried using different times and temperatures to determine which ones were the best heat treatments to be adopted aiming the equalization of mechanical properties. The heat treatments applied after welding proved to be convenient for the leveling of the hardness values, only showing few losses in the HAZs of the Maraging steels. Applying of these treatments, it was also possible to note the equalization of tensile strengths, around 1300 MPa and considerable increases of the same, compared to the same condition without treatment. The welds showed to be efficient for the joining of the plates, however, in some situations the Laser welding presented small flaws, such as presence of pores, in the weld beads, causing to the reduction of the tensile strength limit.
5

Caracterização de juntas soldadas em PAW e GTAW de chapas finas em aço maraging 300 submetidas a vários reparos / Characterization of welded joints by PAW and GTAW Maraging 300 steel sheets submitted to several repairs

Sakai, Paulo Roberto [UNESP] 18 December 2015 (has links)
Submitted by PAULO ROBERTO SAKAI null (prsakai@yahoo.com.br) on 2016-01-15T12:06:37Z No. of bitstreams: 1 CARACTERIZAÇÃO DE JUNTAS SOLDADAS EM PAW E GTAW DE CHAPAS FINAS EM AÇO MARAGING 300 SUBMETIDAS A VÁRIOS REPAROS.pdf: 16627185 bytes, checksum: 4b08baddd60bec8be8acf6956cc8e2ee (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-01-15T12:54:59Z (GMT) No. of bitstreams: 1 sakai_pr_dr_guara_int.pdf: 16627185 bytes, checksum: 4b08baddd60bec8be8acf6956cc8e2ee (MD5) / Made available in DSpace on 2016-01-15T12:54:59Z (GMT). No. of bitstreams: 1 sakai_pr_dr_guara_int.pdf: 16627185 bytes, checksum: 4b08baddd60bec8be8acf6956cc8e2ee (MD5) Previous issue date: 2015-12-18 / Este trabalho tem como objetivo caracterizar mecanica e metalograficamente, juntas soldadas de chapas finas em aço Maraging 300, submetidas a até três reparos, usadas na fabricação de envelopes motores foguete a propelente sólido desenvolvidos no Instituto de Aeronáutica e Espaço (IAE) em atendimento às necessidades de sua gama de lançadores. O envelope motor atua como elemento estrutural e também possui a função primária de suportar a pressão de trabalho durante a queima do propelente. Atualmente, o envelope motor é fabricado em aço 300M-ESR e o IAE tomou a decisão de substituí-lo pelo aço Maraging 300. Em função dos processos existentes no Instituto, neste trabalho utilizaram-se os processos de soldagem Plasma Arc Welding - PAW com a técnica keyhole e Gas Tungsten Arc Welding - GTAW, ambos em passe único, com metal de adição. Antes de serem submetidas aos ensaios, as juntas passaram por inspeção não destrutiva de acordo com os critérios da norma AWS D17.1. Os reparos foram feitos de forma manual e processo GTAW. Amostras da junta soldada e reparadas foram submetidas a ensaios de tração, dureza Vickers (HV) por microindentações, análises químicas, análises metalográficas e fractográficas. Corpos de prova dos cordões adjacentes aos reparos também foram avaliados. Os resultados mostram que após a solda e reparos e o tratamento térmico de solubilização e envelhecimento, a zona fundida e a região da linha de fusão da solda apresentam uma dureza abaixo das outras regiões afetadas termicamente. Para as condições da solda sem reparo e reparadas, o processo PAW apresentou um valor menor de dureza em todas estas regiões com relação ao processo GTAW. As análises da superfície dos corpos de prova soldados rompidos indicam o predomínio de um processo de ruptura iniciado próximo à linha de fusão da solda e que se propaga em direção ao interior do cordão. A natureza da fratura mostrou o domínio da formação de alvéolos (dimples). Os corpos de prova soldados GTAW apresentaram uma resistência mecânica mais alta do que os do processo PAW. Igualmente, os corpos de prova soldados PAW obtidos dos cordões das regiões adjacentes aos reparos tiveram valores de resistência inferiores. Embora os valores de resistência mecânica das juntas soldadas submetidas a até três reparos no mesmo ponto tenham apresentado grande variabilidade, não há indicativo de diminuição da resistência com relação a junta sem reparo. / This work aims at mechanic and metallographic characterization of Maraging 300 welded joints sheets, submitted to up to three repairs, used for the fabrication of solid propellant rocket motors at the Institute of Aeronautics and Space – IAE as to comply with its range of launchers. The rocket motor is a structural part and also has the primary function of supporting the nominal pressure during the propellant burning. At present, the rocket motor is fabricated in 300M-ESR steel and IAE has decided to replace such a steel for the Maraging 300 one. Due to IAE’s existing processes, Plasma Arc Welding – PAW with the keyhole technique and the Gas Tungsten Arc Welding – GTAW have been used, both single-pass welding with filler. Before they have been submitted to the tests, the joints went through non-destructive inspection according to AWS D17.1 Standard. Manual repairs and GTAW process have been made. Samples of the welded and repaired joints were submitted to tensile testing, Vickers hardness, chemical analysis, fractrographic and metallographic analysis. Body tests of the beads adjacent to the repairs have also been assessed. Results show that after welding, repairs and solubilization and aging heating treatment, the melted zone as well as the weld joins lines zone present hardness below other heat affected zones. As for the conditions of the non-repaired and repaired welds, the PAW process has demonstrated lower hardness values in all zones in what regards the GTAW process. The welded and fractured body tests surfaces analysis indicate the predominance of a fracture process started next to the weld joins lines which goes towards the bead interior. The nature of the fracture has shown the predominance of dimples. The GTAW welded body tests presented higher mechanical strength than that of the PAW process. Similarly, the PAW welded body tests obtained from the beads of the zones adjacent to repairs presented lower strength values. Although the mechanical strength values of the welded joints submitted to up to three repairs in the same point have shown great variability, there is no indication of strength decrease regarding the non-repaired joint.
6

Etude par RMN du solide multi-noyaux et modélisation des paramètres RMN de fluorures et d’oxyfluorures inorganiques / Mutinuclear solid state NMR and NMR parameters modeling of inorganic fluorides and oxyfluorides

Dabachi, Jamal 28 April 2017 (has links)
Cette thèse porte sur l’étude structurale de fluorures et d'oxyfluorures, en combinant la RMN du solide, la diffraction des rayons X et les calculs PAW/GIPAW des paramètres RMN. La première partie est consacrée à l’étude des cinq composés du binaire KF-YF3. Des corrélations linéaires entre valeurs expérimentales de déplacements chimiques isotropes et de constantes d’écran isotropes calculées ont été établies pour 19F, 89Y et 39K, à partir des attributions des raies RMN aux sites cristallographiques. Ces corrélations conduisent à des accords satisfaisants. Dans le cas de 19F et 89Y, le lien entre paramètres RMN et environnement a été établie. Les paramètres RMN calculés de 39K permettent des reconstructions satisfaisantes des spectres complexes.La deuxième partie est dédiée à l’étude des deux phases ordonnées de LaOF. Les optimisations et les calculs de valence de liaison montrant que les positions atomiques de F et O devaient être inversées dans ces deux phases, leurs structures ont été réaffinées. L’accord entre paramètres RMN expérimentaux et calculés de 19F et 139La valide nos modèles structuraux. Enfin les composés MO2F (M = Nb, Ta), isotypes et désordonnés vu que les atomes de O et F occupent le même site anionique, ont été étudiés. Il est montré que la synthèse en milieu aqueux conduit à des composés hydroxylés lacunaires dont les compositions ont été déterminées en combinant RMN 19F, DRX sur poudre et ATG. La synthèse en phase solide permet d’obtenir ces composés purs. Les calculs DFT ont été réalisés sur des supermailles 3 × 3 × 3 en respectant l'ordre -M-O-M-O-M-F-. Le bon accord entre paramètres RMN de 19F expérimentaux et calculés valide les modèles proposé. / This thesis focuses on the structural study of fluorides and oxyfluorides by combining solid state NMR, X-ray diffraction and PAW/GIPAW calculations of NMR parameters. The first part is devoted to the study of compounds of the KF-YF3 binary system. Linear correlation between experimental isotropic chemical shift (delta iso) and calculated isotropic shielding (sigma iso) values have been established, for 19F, 89Y and 39K, from assignments of NMR lines to crystallographic sites. These correlations lead to satisfactory agreements. In the case of 19F and 89Y, the link between NMR parameters and environment has been established. The calculated 39K NMR parameters allow satisfying reconstructions of the experimental complex spectra. The second part is dedicated to the study of the two ordered phases of LaOF. The optimizations and bond valence calculations showing that the atomic positions of F and O should be interchanged in both the phases, their structures have been refined. The agreement between experimental and calculated NMR parameters of 19F and 139La validates our structural models. Finally, the isotypic and disordered MO2F (M = Nb, Ta) compounds, since the O and F atoms occupy the same anionic site, have been studied. It is shown that the aqueous solution synthesis leads to hydroxylated and lacunary compounds, whose formulations have been determined by combining 19F NMR, XRD and TGA. The solid state synthesis enables to obtain pure compounds. DFT calculations were carried out on optimized 3 × 3 × 3 supercells that respect the partial order -M-O-M-O-M-F-. The good agreement between experimental and calculated NMR parameters of 19F validates the proposed model.
7

Cálculos ab initio de interações entre Cd e bases nitrogenadas do DNA / Ab Initio calculations of interactions betweeen Cd and nitrogenous bases o DNA

Philippe Alexandre Divina Petersen 11 May 2011 (has links)
As interações hiperfinas são uma ótima ferramenta para estudar um sítio específico e obter informações importantes sobre o sistema. No presente trabalho analisamos de forma teórica as propriedades eletrônicas, estruturais e hiper nas do Cádmio (Cd) ligado às bases nitrogenadas do DNA. A motivação surgiu da colaboração com o grupo do prof. Artur W. Carbonari do Instituto de Pesquisas Energéticas e Nucleares (IPEN) e que tem como objetivo investigar o DNA e anticorpos de linhagens de camundongos infectados pela cepa Y de Trypanosoma cruzi, protozoário causador da doença de Chagas. A técnica Time Differential Perturbed Angular Correlation (TDPAC) foi utilizada para obter as medidas das interações hiperfinas do DNA. O núcleo de prova das medidas foi o 111Cd. Utilizamos uma abordagem quântica ab initio all-electron, dentro da Teoria do Funcional da Densidade (DFT), através do código computacional CP-PAW que combina o método Projector Augmented Wave (PAW) e a dinâmica molecular quântica de Car-Parrinello (CPMD). Ressaltamos que, até o presente momento, nenhum estudo com esta abordagem teórica e com este código computacional foi realizado para investigar as propriedades hiper nas do Cd ligado as bases nitrogenadas do DNA. / The Hyperfine interactions are good tools to study speci c sites and obtain important information about a given system. In this work we study electronic, structural and hyper ne properties of the Cadmium (Cd) coordinated to the DNA nitrogenous bases. The motivation for this study arose from a collaboration with the group of prof. Arthur W. Carbonari at the Institute of Energy and Nuclear Research (IPEN), which aims to investigate DNA and antibodies to strains of mice infected with the Trypanosoma cruzi, the protozoan that causes Chagas disease. The Time Differential Perturbed Angular Correlation (TDPAC) technique was used to obtain hypefine interactions measurements at a Cd probe bonded to DNA. We use ab initio all-electron calculations, within the Density Functional Theory (DFT) and we use the computer code CP-PAW that combines the Projector Augmented Wave (PAW) method and the Car-Parrinello (CP) quantum molecular dynamics approach to. We emphasize that, until now, no study with this theorectical approach and with this computer code was conducted to investigate the hyper ne properties of the Cd binding to the DNA bases.
8

Agents utilisateurs pour la protection des données personnelles : modélisation logique et outils informatiques

Piolle, Guillaume 02 June 2009 (has links) (PDF)
Les usages dans le domaine des systèmes multi-agents ont évolué de manière à intégrer davantage les utilisateurs humains dans les applications. La manipulation d'informations privées par des agents autonomes appelle alors à une protection adaptée des données personnelles. Les présents travaux examinent d'abord le contexte légal de la protection de la vie privée, ainsi que<br />les divers moyens informatiques destinés à la protection des données personnelles. Il en ressort un besoin de solutions fondées sur les méthodes d'IA, autorisant à la fois un raisonnement sur les réglementations et l'adaptation du comportement d'un agent à ces réglementations. Dans cette perspective, nous proposons le modèle d'agent PAw (Privacy-Aware) et la logique DLP (Deontic Logic for Privacy), conçue pour traiter des réglementations provenant d'autorités multiples. Le composant de raisonnement normatif de l'agent analyse son contexte hétérogène et fournit une politique cohérente pour le traitement des données personnelles. L'agent PAw contrôle alors automatiquement sa propre utilisation des données en regard de cette politique. Afin d'appliquer cette politique de manière distante, nous étudions les différentes architectures d'applications distribuées orientées vers la protection de la vie privée, notamment celles fondées sur les principes du Trusted Computing. Nous en proposons une complémentaire, illustrant la possibilité d'utiliser différemment cette technologie. L'implémentation de l'agent PAw permet la démonstration de ses principes sur trois scénarios, montrant ainsi l'adaptabilité de l'agent à son contexte normatif et l'influence des réglementations sur le comportement de l'application.
9

Zavedení a optimalizace \kur{in vivo} modelů zánětu a jejich využití pro funkční analýzu inhibitorů proteáz z klíštěcích slin

CHLASTÁKOVÁ, Adéla January 2016 (has links)
Two murine models of acute inflammation, namely thioglycollate-induced peritonitis and carrageenan-induced paw edema, were optimized using non-steroidal anti-inflammatory drug indomethacin and corticosteroid dexamethasone. During the optimization phase, the presence of neutrophils, monocytes, macrophages, eosinophils, B cells and T cells in the peritoneal cavity at various time points after injection of thioglycollate medium was assessed via multicolor flow cytometry. Moreover, two different thioglycollate media (suppliers BD and Sigma-Aldrich) were compared for their ability to induce an inflammatory response. The optimization of thioglycollate-induced peritonitis and carrageenan-induced paw edema was followed by the evaluation of the anti-inflammatory activity of Ixodes ricinus cystatins G1 and G9 in both mouse models.
10

Estudo comparativo de carragenanas comerciais Kappa, Iota e Lambda no processo inflamat?rio em ratos :edema intraplantar e pleurisia

Silva, Fernando Roberto Ferreira 19 July 2005 (has links)
Made available in DSpace on 2014-12-17T14:03:43Z (GMT). No. of bitstreams: 1 FernandoRFS2.pdf: 536272 bytes, checksum: 3a3c1cb63097447c30d5446bdc4b166a (MD5) Previous issue date: 2005-07-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The Iota, Kappa and Lambda commercial carrageenans are rarely pure and normally contain varying amounts of the other types of carrageenans. The exact amount of impurity depends on the seaweed source and extraction procedure. Then, different analysis methods have been applied for determination of the main constituents of carrageenans because these three carrageenans are extensively used in food, cosmetic and pharmaceutical industry. The electrophoresis of these compounds proved that the carrageenans are constituted by sulfated polysaccharides. These compounds were characterized by colorimetric methods and was observed that the Lambda carrageenan shown the greater value (33.38%) of sulfate. These polymers were examined by means of 13C NMR spectroscopy and infrared spectra. The polysaccharides consisted mainly of units alternating of sulfated galactoses and anhydrogalactoses. The aim of the study was also to test the inflammatory action of these different polysaccharides. A suitable model of inflammation is acute sterile inflammation of the rat hind limb induced by carrageenan. Paw edema was induced by injecting carrageenans (&#x3ba;, &#953; and &#955;) in saline into the hind paw of a male Wistar rats (175&#8211;200 g). The pathway to acute inflammation by carrageenan (kappa, iota and lambda) were expressed as time-edema dependence and measured by paw edema volume. For this purpose, was used an apparatus (pakymeter), which makes it possible to measure the inflammation (swelling of the rat foot) with sufficient accuracy. The results showed that &#954;-carrageenan (1%) have an edema of 3.7 mm and the paw edema increase was time and dose dependent; the &#953;-carrageenan (0.2%) caused an edema of 4 mm and the &#955;-carrageenan (1%) caused an edema of 3.6 mm. Other model was used in this study based in the inflammation of pleura for comparatives studies. Injection of carrageenans into the pleural cavity of rat induced an acute inflammatory response characterized by fluid accumulation in the pleural cavity, a large number of neutrophils and raised NO production. The levels of NO were measured by Griess reactive. The &#953;-carrageenan caused the greater inflammation, because it has high concentration of nitrite/nitrate (63.478 nmoles/rat), exudato volume (1.52 ml) and PMNs (4902 x 103 cells). Quantitative evaluation of inflammations of rats is a useful and important parameter for the evaluation of the efficacy of anti-inflammatory drugs / As carragenanas comerciais Iota, Kappa e Lambda s?o raramente puras e, normalmente, apresentam v?rios outros tipos de pol?meros. A quantidade exata de impurezas depende do m?todo de extra??o e da alga utilizada. Logo, diferentes m?todos t?m sido utilizados para a determina??o do conte?do das carragenanas, tento em vista que elas s?o extensivamente usadas nas ind?strias aliment?cia, de cosm?ticos e farmac?utica. A eletroforese desses compostos provou que eles s?o constitu?dos de polissacar?deos sulfatados. Estes compostos foram caracterizados por m?todos colorim?tricos e foi observado que a carragenana Lambda possui o maior teor de sulfato (33,38%). Esses pol?meros foram analisados por espectroscopias de IV e 13C RNM. Estes polissacar?deos consistem principalmente de unidades alternadas de galactose e anidrogalactose sulfatadas. Foi poss?vel avaliar a a??o inflamat?ria desses diferentes compostos atrav?s de um modelo cl?ssico de inflama??o, que ? o de inflama??o aguda, na pata de ratos, induzida por carragenanas. O edema plantar foi induzido pela inje??o das carragenanas (&#x3ba;, &#953; e &#955;) na pata direita de ratos machos da ra?a Wistar (175-200g). A inflama??o aguda induzida por carragenanas foi expressa pela rela??o tempo-edema e medida pelo volume do edema plantar. Para isto, foi utilizado um paqu?metro, que confere mais precis?o a mensura??o da inflama??o (incha?o na pata do rato). Os resultados mostraram que a carragenana Kappa (1%) induz um edema de 3,7mm e o aumento de volume do edema ? tempo e dose-dependente; a Iota (0,2%) provoca um edema de 4mm; e a Lambda (1%) um edema de 3,6mm. O outro modelo usado neste estudo comparativo ? baseado na inflama??o da pleura (pleurisia). A inje??o de carragenanas na cavidade pleural dos ratos induz uma resposta inflamat?ria aguda caracterizada pelo acumulo de l?quido na cavidade pleural, um grande n?mero de neutr?filos e aumento na produ??o de NO. A carragenana Iota provocou a inflama??o intensa, o que pode ser comprovado pela verifica??o do volume do exudato (1,52 ml), o teor de nitrato/nitrito (63,478 nmol/rato) e a contagem de leuc?citos polimorfonucleares - PMN (4902 x 103 c?lulas). A avalia??o quantitativa da inflama??o em ratos ? um par?metro importante para a avalia??o da efic?cia de drogas antiinflamat?rias

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