Dissertations / Theses: 'C3b'

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Paramaswara, Bamini. "Characterization of the promoter for the human factor I (C3b/C4b inactivator) gene." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ34077.pdf.

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Jakob, Stephan Mathias. "Klinische und biochemische Aspekte des vollständigen, hereditären Komplement Faktor I-(C3b/C4b-Inaktivor)Mangels /." Bern, 1990. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

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Holme, E. R. "C3b receptors (CR1) on peripheral human blood cells." Thesis, University of Glasgow, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381473.

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Kucukkilic, Ezgi. "Copy number variation and relevance to disease of the complement C3b/C4b receptor 1 (CR1) gene." Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/40701.

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The complement 3b/4b receptor 1 (CR1) gene is located at chromosome 1q32.2 in a cluster of complement-related genes. CR1 regulates both classical and alternative pathways of the complement system. CR1 is a major receptor for Plasmodium falciparum, and variation within the gene has been associated with different malarial clinical phenotypes. CR1 shows intragenic copy number variation (CNV) resulting in variation in protein length and number of C3b/C4b binding domains. Previously, CR1 was related to Alzheimer’s disease (AD) via complement system regulation. Furthermore, CR1 variation is responsible for the alleles of the Knops blood group, including McCoy and Swain-Langley. In this thesis, Novel paralogue ratio test (PRT) assays were developed to robustly type CNV of the low-copy repeat (LCR) regions (which defines the common CR1-A and CR1-B alleles, but also rarer alleles) within the gene in large cohorts, and an allele-specific hybridisation assay to genotype alleles of the Knops blood group system. Variation was analysed across global populations, and in the Tori-Bossito cohort (563 infants) from Benin, followed since birth to observe malaria acquisition and treatment. This showed that the Swain-Langley Sl2 polymorphism is not in strong linkage disequilibrium (LD) with the CNV, nor with other Knops blood group alleles. It appears to provide protection against early acquisition of malaria and subsequent number of malarial infections in the Tori-Bossito cohort but these results were not confirmed in an independent cohort (n=276). The association between the CR1-B allele and AD (early-onset (EOAD) and late-onset (LOAD)) was explored, showing that the CR1 risk loci (rs3818361, rs6656401 (only for EOAD) and rs6701713) were in moderate LD with CR1-B, but revealing no association between CR1-B (p=0.755) and EOAD (n=633). However, the CR1-B allele (risk) appears to be associated with LOAD (n=2185) with (p=0.015) and without (p=0.048) use of a junction fragment PCR assay.

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Birmingham, Daniel J. "The characterization of the baboon erythrocyte C3b binding protein /." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu148767311411266.

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Chaumonnot, Killian. "La protéine de choc thermique Gp96 dans les macrophages au cours du stress du RE : Interaction avec le complément C3." Thesis, Bourgogne Franche-Comté, 2020. http://www.theses.fr/2020UBFCJ002.

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La protéine de stress Gp96, est une protéine du réticulum endoplasmique (RE) de la famille des HSP90, exprimée dans toutes les cellules. En situation de stress du RE, elle est induite et peut alors être exprimée au niveau membranaire et extracellulaire. Gp96 est connue pour moduler de manière ambivalente les réponses immunitaires, ayant des effets à la fois pro- et anti-inflammatoires. Bien qu’elle ait été montrée nécessaire pour la tolérance au microbiote des macrophages intestinaux, son rôle n’a pas été pas élucidé au niveau moléculaire. De plus, ses effets dans les macrophages en situation de stress du RE n’est pas connu, malgré leur implication dans de nombreuses pathologies. Dans ces travaux, nous montrons dans un premier temps que Gp96 est exprimée à la membrane des macrophages M2 et non des macrophages M1 dérivés de monocytes du sang périphérique de volontaires sains. Nous mettons en évidence que le stress du RE, généré par la perturbation de l’homéostasie calcique induite par la thapsigargine (Tg), a pour conséquence un switch du phénotype M2 vers un profil pro-inflammatoire dépendant de Gp96 fonctionnelle. Ce switch est associé à la diminution de l’expression membranaire de Gp96 et à sa sécrétion. Dans un second temps, nous démontrons que Gp96 interagit avec le complément C3 intracellulaire dans les macrophages M1 et M2. Cette interaction est plus importante dans les macrophages M2 stressés comparé aux M2 non stressés et, C3b, le fragment issu du clivage de C3, est présent uniquement dans le surnageant de culture des M2 stressés, et a pu de plus être co-immunoprécipité avec Gp96. Enfin, comme Gp96, le fragment inactivé de C3b, iC3b, est détecté uniquement à la membrane des M2 non stressés et sa présence dépend de Gp96 fonctionnelle. Ces résultats suggèrent que Gp96 membranaire et iC3b pourraient être des marqueurs des macrophages M2 anti-inflammatoires. Ils montrent que Gp96 est impliquée dans la modulation du phénotype M2 vers un profil pro-inflammatoire induite par une perturbation de l’homéostasie du calcium. Cet effet pourrait être lié à sa capacité à interagir avec le complément C3 dont les fragments de clivage C3a et C3b ont des effets pro-inflammatoires
The stress protein Gp96, is an endoplasmic reticulum (ER) protein of the HSP90 family, expressed in all cells. Under ER stress, it is induced and can then be expressed at the membrane and extracellular levels. Gp96 is known to have a dual role in immune responses, having both pro- and anti-inflammatory effects. Although it has been shown to be necessary for the tolerance of intestinal macrophages to the microbiota, its role has not been elucidated at the molecular level. Moreover, its effects in macrophages under ER stress are not known, despite their involvement in many pathologies. In this work, we first show that Gp96 is expressed at the membrane of M2 and not M1 macrophages derived from blood monocytes of healthy volunteers. We show that ER stress, generated by the disruption of calcium homeostasis induced by thapsigargine (Tg), results in a switch from the M2 phenotype to a functional Gp96-dependent pro-inflammatory profile. This switch is associated with the decrease in membrane expression of Gp96 and its secretion. In a second step, we demonstrate that Gp96 interacts with intracellular complement C3 in macrophages M1 and M2. This interaction is more important in stressed M2 macrophages than in untreated M2 and, C3b, the fragment resulting from the cleavage of C3, is present only in the culture supernatant of the stressed M2, and could moreover be co-immunoprecipitated with Gp96. Finally, like Gp96, the inactivated fragment of C3b, iC3b, is detected only at the membrane of unstressed M2 and its presence is dependent on functional Gp96. These results suggest that membrane Gp96 and iC3b could be markers of anti-inflammatory M2 macrophages. They show that Gp96 is involved in the modulation of the M2 phenotype towards a pro-inflammatory profile induced by a disruption of calcium homeostasis. This effect could be related to its ability to interact with the C3 complement whose C3a and C3b cleavage fragments have pro-inflammatory effects

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Ng, Y. C. "Complement and the C3b receptor (CR1) in immune complex associated with disease." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382666.

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Serra, Vincent. "Influence de l'association C3b-toxine tétanique sur la production de peptides immunogéniques." Université Joseph Fourier (Grenoble), 1998. http://www.theses.fr/1998GRE10046.

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La proteine c3 est impliquee dans de nombreux mecanismes de defense de l'organisme contre des elements etrangers pathogenes. C3 participe a la reponse immune naturelle : element clef du syteme du complement, elle intervient dans l'elimination des complexes immuns. Cette proteine participe egalement a la reponse immune specifique : son influence dans l'activation b a clairement ete etablie. Un role dans l'appretement et la presentation de l'ag a egalement ete suggere. Mon projet de recherche a vise a determiner l'influence de c3b sur la generation de peptides antigeniques de la tt au cours de l'appretement dans la cpa. Je me suis d'abord interesse a mieux definir les effets de l'association de c3b a la toxine tetanique (tt) dans la presentation par les cpa aux cellules t. Les complexes tt-c3b activent tous les clones t specifiques des epitopes p2 et p30 a des doses 100 fois moins importantes, par rapport a la tt libre. Cette meilleure efficacite de presentation des cpa ne resulte pas, dans mon systeme experimentale, d'une modification de neosynthese de molecules hla-dr ou de b7. Mon etude s'est portee dans un deuxieme temps sur l'analyse de l'influence des complexes tt-c3b sur la stabilite en sds des molecules hla-dr. L'appretement de complexes tt-c3b permet la synthese de 2 fois plus de formes hla-dr1 compactes qu'avec la tt libre. Ces resultats demontrent que la proteine c3b modifie une ou plusieurs etapes de l'appretement de l'ag qui lui est associe. La production de formes hla-dr compactes en presence de complexes tt-c3b est preferentiellement observee dans les compartiments tardifs de la voie endocytaire, de type lysosomal. Je me suis enfin efforce de determiner les sequences des peptides de la tt naturellement generes par une cpa et associes aux molecules hla-dr, ainsi que d'analyser l'influence de l'association de c3b. L'appretement des complexes tt-c3b permet de generer des epitopes t differents de ceux de la tt, dont la quantite (ou l'immunogenicite) est responsable d'une meilleure activation des clones t utilises. Ces resultats suggerent donc un role direct de c3b dans la generation des epitopes t au cours de l'appretement de la tt, en favorisant la production de peptides immunogeniques differents, capables de se lier aux molecules hla-dr et d'activer de facon plus importante les clones t specifiques.

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9

Kisserli, Aymric. "Distribution, rôle et régulation du CRI (CD35, récepteur pour le C3b/C4b) érythrocytaire. Analyse de dépôts érythrocytaires de fractions du complément." Reims, 2008. http://theses.univ-reims.fr/exl-doc/GED00000886.pdf.

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CR1 (CD35, récepteur pour le C3b/C4b) est une glycoprotéine transmembranaire présente sur de nombreux types cellulaires. Son rôle principal à la surface des érythrocytes (E) est le transport des complexes immuns vers le foie et la rate où ils sont éliminés. Nous avons montré que le Macaque rhésus (Macaca mulatta, MM) exprime un CR1 équivalent à celui de l’Homme en taille, en densité et réparti en bouquets. Ce CR1 présente des polymorphismes allotypiques. Il exprime aussi un CR1 plus court (CR1like, CR1L), plus abondant, plus diffus, à ancrage glycophosphatidylinositol. Nous avons décrit des polymorphismes de la région Sla de CR1 impliquée dans les phénomènes d'adhérence inter-érythrocytaire entre les E parasités par P. Falciparum et les E sains chez 12 espèces de primates. Ils ne protègent pas les E de MM contre la formation des rosettes avec des E humains parasités. Nous avons séquencé les promoteurs de CR1 et CR1L de MM (MCR1, MCR1L). AML1 activateur de CR1 humain est présent dans MCR1 mais absent de MCR1L. Ets et MZF1 sont conservés. Nous avons identifié un polymorphisme allèlique (délétion de 18 nucléotides) dans CR1L humain. Nous avons étudié le dépôt de C4d érythrocytaire (EC4d) de transplantés rénaux concomitamment à l'analyse de la biopsie du greffon. Il existe une relation entre le EC4d et le marquage diffus C4d des capillaires péritubulaires du greffon ; et entre le EC4d et les lésions histologiques retrouvées en situation de rejet aigu humoral. Le EC4d offre un intérêt pour le diagnostic et le suivi des rejets en transplantation rénale. Le mécanisme des dépôts de C4d reste à élucider. L’activation de la voie classique du complément ne semble pas impliqué
@CR1 (CD35, the C3b/C4b receptor) is a transmembrane glycoprotein found on few cell types. Erythrocyte CR1 (E-CR1) is involved in immune complex (IC) clearance in liver and spleen. The binding of IC on E is improved by cluster distribution of CR1 enabling a strong avidity multivalent binding. Rhesus macaque (Macaca mulatta) was shown to express a transmembrane E-CR1 as observed in Human (same length, density, cluster distribution). This “human-type” CR1 was characterized by allotypic polymorphisms. A shorter CR1 was also observed, called CR1like (CR1L) which was more abundant, more diffuse and glycophosphatidylinositol anchored. Polymorphisms of CR1 Sla region involved in rosetting between healthy E and P. Falciparum infected E were described in 12 primate species. E from rhesus macaque were not prevented from rosetting with human infected E by those polymorphisms. CR1 and CR1L promoters from rhesus macaque (MCR1, MCR1L) were sequenced. AML1 known as human CR1 activator was found in MCR1 but was missing in MCR1L. Ets and MZF1 were conserved. HES1 et LBP1 might downregulate MCR1 and human CR1L. An allelic polymorphism corresponding to a 18 nucleotide deletion was observed in human CR1L promoter. C4d deposition at E surface (EC4d) of patients suffering from kidney acute humoral rejection was compared with biopsy analysis and related to C4d tissue deposits. EC4d appears a promising non-invasive marker of acute humoral rejection. The mechanism of C4d deposition remains to be investigated. Complement classical pathway activation did not seem to be involved

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Soames, Candida J. "Factor H : a major complement regulatory protein." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307011.

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Rey-Millet, Macary Catherine. "Association covalente antigène-protéine C3b du complément : rôle dans l'apprêtement intracellulaire de l'antigène." Grenoble 1, 1993. http://www.theses.fr/1993GRE10212.

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La proteolyse limitee de c3 est induite, soit lors de l'activation du complement par les c3 convertases, soit par d'autres proteases (trypsine). Cette proteolyse conduit a la formation d'un fragment c3b doue du pouvoir de former une liaison covalente de type ester ou amide avec des proteines solubles ou membranaires. C3b peut egalement interagir de facon non covalente avec des recepteurs specifiques. C3b, proteine bivalente, peut donc jouer un role preponderant au cours de la reponse immune. C3b est notamment implique dans les etapes conduisant a la presentation d'un antigene aux lymphocytes t. Afin d'etudier l'influence de c3b sur ces differentes etapes, nous avons elabore un systeme modele constitue de c3b lie a une particule de superose par liaison ester. Nous utilisons comme cpa la lignee monocytaire humaine u937. En presence de fractions purifiees enrichies en endosomes/lysosomes la liaison ester est stable. C3b est partiellement proteolyse en c3c et en un fragment de 32 kda c3d-like qui reste lie au superose par liaison ester. Ceci suggere que c3b peut evoluer lors du trafic intracellulaire en restant lie a l'ag. L'utilisation d'inhibiteurs de proteases nous a permis d'observer que des enzymes appartenant a la famille des proteases acides, a serine, et a cysteine dont la cathepsine b, cooperent aux activites esterolytiques et proteolytiques exercees par la fraction enrichie en endosomes/lysosomes, sur le c3b-superose. Pour poursuivre l'etude in situ, nous avons incube les cellules u937 en presence de complexes formes de c3b lie a la toxine tetanique (tt) par liaison ester, et adopte une technique permettant de separer les lysosomes des endosomes. Cette etude a montre que c3b influence la prise en charge, le routage intracellulaire et la proteolyse de la tt. Ceci se traduit sur un plan fonctionnel: l'ag, plus tardivement disponible a partir des complexes tt-c3b, est presente avec plus d'efficacite que l'ag libre aux lymphocytes t specifiques de la tt. L'influence de c3b sur ces etapes est due a la stabilite de la liaison ester au cours du trafic intracellulaire. Par ailleurs, nous avons mis en evidence un effet modulateur direct de c3 sur la proteolyse de la tt dans les lysosomes. C3, proteolyse dans ces fractions, parait agir directement sur les proteases des lysosomes, sans intervenir comme competiteur de la tt

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Mallin, Rosie L. "Structural study of the C3b-binding site of complement receptor type 1 (CD 35)." Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/15256.

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GREDY, PHILIPPE. "Etude du polymorphisme de longueur du gene du recepteur pour le fragment c3b/c4b du complement (cr1-cd35) chez des patients lupiques et des sujets sains." Reims, 1991. http://www.theses.fr/1991REIMMO96.

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Jacquier, Muriel. "Association covalente de C3b à la toxine tétanique : rôle dans l'apprêtement et la présentation de l'antigène aux lymphocytes T." Grenoble 1, 1992. http://www.theses.fr/1992GRE10200.

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Le travail presente constitue une premiere etape dans l'etude du role du ligand bifonctionnel c3b associe la toxine tetanique, sur la fonction d'appretement et de presentation de cet antigene par des clones b humains transformes par le virus d'epstein-barr, specifiques de la toxine tetanique, aux lymphocytes t. Dans une premiere partie, l'analyse en sds-page des fragments de c3b fixes sur les lymphocytes b indique que 60% de cette proteine est impliquee dans la formation de complexes covalents par pont disulfure avec des proteines membranaires et 40% dans des interactions non covalentes avec les recepteurs cellulaires du complement. L'implication de la cys1010 du thioester dans la formation des complexes covalents a ete confirmee apres alkylation de cet unique groupement sh libre par l'iodoacetamide. Lorsque ces cellules sont preincubees avec la toxine tetanique puis avec #1#2#5i-c3b, des complexes disulfure #1#2#5i-c3b-tt sont immunoprecipites a partir des lysats subcellulaires avec des antiserum contre c3 ou la tt. L'expression membranaire et la secretion dans les surnageants de culture d'une proteine reconnue par des anticorps anti-thioredoxine suggerent l'implication de cette enzyme dans la formation du disulfure. Dans une seconde partie, nous avons analyse le role de l'association covalente de c3b a la toxine tetanique, sur l'appretement et la presentation de la tt aux lymphocytes t, par ces clones b specifiques. Deux types de complexes c3b-tt ont ete utilises: des complexes disulfure ou des complexes ester prepares in vitro. L'analyse a ete faite en gel sds-page a partir de proteolysats obtenus apres endocytose de l'antigene in situ, ou par des fractions subcellulaires enrichies en lysosomes. Les resultats indiquent que les fragments de proteolyse de tt observes a partir de la tt ou de c3b-tt sont identiques. Des experiences de cinetiques revelent un effet retard de la proteolyse de la tt elle est associee a c3b. D'autre part, la presentation par des cellules b fixees de proteolysats de tt seule ou de c3b-tt obtenus a differents temps, montre que la production de peptides est maximale a 6 heures de traitement avec la tt, alors qu'elle est maintenue au bout de 24 heures avec les complexes. Ces derniers constituent un reservoir d'ag dans la cellule presentatrice et assurent une liberation graduelle de peptides immunogenes responsables d'une stimulation (10) de la proliferation des cellules th specifiques. Ces effets sont a relier a la stabilite de la liaison ester ou disulfure dans les compartiments subcellulaires, ainsi qu'au role chaperon de c3b. L'utilisation de cathepsines purifiees indique que cet effet protecteur de c3b resulte d'une susceptibilite differente pour les proteases intracellulaires de la tt seule ou associee a c3b

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APPAY, MARIE-DOMINIQUE. "Etude de la localisation et de la synthese du recepteur cr1 (cd35) du fragment c3b du complement dans le rein humain." Paris 6, 1990. http://www.theses.fr/1990PA066781.

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Le recepteur cr1 (cd35) du fragment c3b du complement a ete detecte sur la membrane cytoplasmique, dans l'appareil de golgi et dans les vesicules d'endocytose des podocytes du rein humain normal, par immunofluorescence et en immunohistochimie ultrastructurale. Le cr1 est un marqueur precoce de differenciation des podocytes du rein ftal. L'expression antigenique du cr1 est alteree dans trois types de maladies glomerulaires. Le cr1 est le seul type de recepteur des fractions du c3 present a la surface des glomerules. Ceci a ete demontre par la fixation de rosettes et par l'inhibition de cette fixation a l'aide d'anticorps anti-c3. Le cr1 glomerulaire purifie possede la meme fonction d'inhibition de la formation de la c3 convertase alterne que le cr1 isole des globules rouges. L'arnm du cr1 a ete mis en evidence dans les glomerules immatures du rein ftal par hybridation in situ avec une sonde d'adn complementaire de l'arnm du cr1, marquee au s#3#5. L'arnm du cr1 n'a pas pu etre detecte dans les glomerules matures ftaux ni dans les glomerules du rein adulte. Par contre, l'arnm du cr1 est exprime dans tous les cas de glomerulonephrites lupiques etudies, mais pas de facon constante dans les autres cas de glomerulonephrites. La presence d'arnm du cr1, detecte dans un cas de nephroblastome a permis d'etablir que les cellules proliferantes sont des podocytes immatures

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PORTEU, DE LA MORANDIERE FRANCOISE. "Recepteur cr1 pour le fragment c3b du complement : modulation de la fonction et de l'expression du cr1 sur les cellules phagocytaires humains." Paris 6, 1988. http://www.theses.fr/1988PA066487.

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Etude du taux de recepteurs cri presents a la surface des neutrophiles dans deux pathologies: le deficit genetique en facteur i et le lupus erythemateux dissemine. Dans les deux cas, les defauts fonctionnels ne sont pas associes a une diminution du nombre de recepteurs cri a la surface des cellules. Etude in vitro de l'effet modulateur du c3b sur son recepteur. L'expression du cri a la surface des neutrophiles de sujets normaux augmente apres incubation de ces cellules avec du c3b. Mise en evidence d'une cooperativite negative entre les sites cri. Implication dans les deux maladies envisagees

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Porteu, Françoise. "Récepteur CR1 pour le fragment C3b du complément modulation de la fonction et de l'expression du CR1 sur les cellules phagocytaires humaines /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37617665h.

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Devaux, Patricia. "Une molécule CD46 et deux fonctions : récepteur du virus de la rougeole et régulateur de l'activation du complément." Paris 7, 1998. http://www.theses.fr/1998PA077036.

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La molécule CD46 humaine est à la fois un régulateur de l'activation du complément humain et un récepteur du virus de la rougeole. La régulation de l'activation du complément protège les cellules de l'organisme contre I' «auto»-agression du complément. Notre objectif a été de déterminer quelle est la conséquence d'une mise en jeu simultanée de ces deux fonctions. 1-Les interactions moléculaires, entre les partenaires viraux et cellulaires impliqués dans l'entrée du virus, ont été étudiées, à l'aide de formes recombinantes solubles des molécules CD46 et hémagglutinine. (i) L'interaction entre les domaines extracellulaires de l'hemagglutinine du virus de la rougeole et de son récepteur, la molécule CD46 humaine, est la première étape de l'entrée du virus. (ii) Le virus de la rougeole et la forme soluble de l'hémagglutinine du virus ont des sites communs de liaison sur les domaines SCR I et II de CD46, et les SCR III et IV renforcent la liaison du virus. Comme la fonction de régulation de l'activation du complément est localisée au niveau des SCR II, III, et IV, il y a chevauchement entre les deux fonctions de CD46. 2-Nous avons établi les paramètres cinétiques et quantitatifs du dépôt de l'élément C3b du complément humain, et sa régulation par la molécule CD46. (i) L'activation du complément sur des cellules xénogéniques, conduit successivement à un faible puis un fort dépôt de C3b. (ii) L'activation de la voie classique est plus rapide et plus efficace que la voie alterne, mais seulement dans l'induction du dépôt initial de C3b. (iii) La molécule CD46 retarde seulement le dépôt initial du C3b de la voie alterne, et bloque le second dépôt des deux voies d'activation. 3-Lors de la mise en jeu des deux fonctions de CD46: (i) la liaison du virus est insensible au C3b pré-déposé; (ii) le virus de la rougeole active la voie alterne du complément, (iii) l'infection ou du virus préfixé à la surface des cellules, augmente le dépôt de C3b. Nous proposons un modèle de l'entrée du virus de la rougeole dans une cellule cible via la molécule CD46, un modèle du dépôt de C3b et de sa régulation par la molécule CD46 lors de l'activation du complément, et un modèle des perturbations réciproques entre la fonction immunologique de la molécule CD46 et sa fonction récepteur pour le virus de la rougeole

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Le, Mignon Maxime. "Régulation de la voie alterne du complément par le facteur H : élucidation de son assemblage avec C3b par marquage oxydatif et pontage chimique couplés à la spectrométrie de masse." Thesis, Evry-Val d'Essonne, 2010. http://www.theses.fr/2010EVRY0006.

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La formation du complexe C3b-H est essentielle au bon fonctionnement de la voie alterne du système du complément puisqu’elle permet d’inhiber la formation du complexe d’attaque membranaire à la surface de nos cellules, préservant l’organisme de toute destruction auto-immune. L’interaction de H avec C3b permet notamment de favoriser l’inactivation protéolytique de C3b par le facteur I, bloquant de ce fait l’activation de la voie alterne. Malgré l’importance du complexe C3b-H, l’interaction entre ces deux protéines à l’échelle moléculaire reste méconnue. En effet, à l’heure actuelle, aucune structure tridimensionnelle de ce complexe n’a pu être obtenue, que ce soit par cristallographie ou par résonance magnétique nucléaire, en raison de sa taille (335 kg.mol-1) et de la flexibilité de H. Cependant, la connaissance de l’organisation de ce complexe est nécessaire à la compréhension de la régulation de la voie alterne et pourrait de plus, se révéler utile quant au développement de thérapies vis-à-vis des maladies auto-immunes tel que le syndrome hémolytique et urémique atypique. Au cours de ces travaux, nous nous sommes donc intéressés à l’étude du complexe C3b-H à l’échelle de l’édifice entier par marquage oxydatif et pontage chimique couplés à la spectrométrie de masse. Ces approches expérimentales nous ont ainsi permis de proposer, à l’échelle de la molécule entière, un modèle tridimensionnel de ce complexe de haut poids moléculaire
The C3b-H complex plays an essential role in regulation of the complement alternative pathway (AP) because it blocks the attack membrane complex (MAC) formation on our self-surface, thus preserving host from autoimmune disease. The C3b-H interaction leads to the proteolytic inactivation of C3b induced by factor I, thus blocking the MAC formation and consequently AP activation. Despite this importance of C3b-H complex for the innate immunity, the mechanism of interaction between these two molecules at the molecular level remains to be established. Indeed, up to date, no three-dimensional structure of this complex is available, either by X-ray crystallography or nuclear magnetic resonance, due to its large size (335 kg.mol-1) and flexibility of H. Yet, these data are required for a better understanding of AP regulation and, might moreover, be useful for the implementation of therapy against autoimmune disorders. In this study, we investigate the C3b-H complex by using oxidative footprinting and cross-linking coupled with mass spectrometry. Our experimental approaches have been successfully applied, allowing us to propose a three-dimensional model of this high molecular complex

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Santoro, Lyse. "Appretement et présentation d'un anticorps monoclonal murin par une lignée monocytaire ou lymphocytaire B humaine : influence de la liaison covalente entre anticorps et fragment C3b du complément." Grenoble 1, 1994. http://www.theses.fr/1994GRE10126.

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La proteine c3 du complement influence l'elaboration de la reponse immune specifique dirigee contre un antigene defini. L'etude presentee dans cette these contribue a demontrer que le fragment c3b du complement, en se fixant de facon covalente a un antigene d'origine exogene, module l'appretement de l'antigene par une cellule presentatrice de l'antigene. Des donnees bibliographiques recentes concernant l'appretement d'antigenes, le fragment c3b et son implication dans la reponse immune specifique sont presentees dans un chapitre d'introduction. L'etude experimentale decrite a ete realisee en utilisant des anticorps monoclonaux murins comme antigenes et des cellules monocytaires ou lymphocytaires b humaines comme cellules presentatrices ; des complexes covalents anticorps monoclonaux-c3b ont ete produits et caracterises. Les resultats obtenus sont exposes dans trois chapitres. Dans un premier chapitre, des experiences montrent que la presentation d'anticorps monoclonaux murins a des cellules t humaines specifiques de ces anticorps est modulee lorsqu'ils sont complexes au fragment c3b. Puis certaines des principales etapes de l'appretement des anticorps utilises sont caracterisees dans des cellules monocytaires u937 ou lymphocytaires b humaines non specifiques de l'antigene (fixation a des recepteurs membranaires, internalisation, transit intracellulaire, modifications biochimiques) ; enfin, l'influence de la liaison covalente entre anticorps et c3b sur ces differentes etapes est mise en evidence. Des hypotheses sont proposees concernant un role chaperon de c3b

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21

Favero, Marco. "Modern in-situ XRD investigations on C3S-C3A-GY systems." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3423113.

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The origin of cement, employed as a binding material, can be attributed to Romans who found that a mixture of lime and crushed volcanic ashes was able to set under water, the resistance being increased along the time, in a way completely different to any other material. Since that age, a huge amount of different kind of cements have been produced to satisfy the request of different mechanical behaviors. To deeply understand the mechanisms that lead to the development of mechanical strength, reaction kinetics that occur during the hydration process must be known. Nowadays we can affirm that cement research has set many important results but despite of this “long-time story”, a lot of improvements are required to better understand the mechanisms of kinetics. Cements mixed with water are complex systems undergoing critical chemical and physical changes during the hydration process. A unique hydration model able to explain the controlling mechanisms is the main purpose of cement research, but the physical-chemical parameters involved are actually too many. To partly overcome the chemical complexity of common cement materials, simplified cement systems are often used for research purposes. A project has been set to investigate the fundamental reactions occurring during the hydration process and has been divided within 3 different partners: NIST (National Institute of Standards and Technology), W.R. GRACE and University of Padua. Our part of the project was to collect x-ray powder diffraction patterns on the hydrating suspensions, using Rietveld refinement for quantitative phase analysis. Three simplified cement systems formed by the synthetic phases tricalcium silicate Ca3SiO5 (C3S), tricalcium aluminate Ca3Al2O6 (C3A) and a varying amount of gypsum CaSO4∙2H2O (CŠH2) were investigated by means of in-situ x-ray powder diffraction (XRPD) and isothermal calorimetry (IC) in order to evaluate dissolution-precipitation kinetics. The main hydration products detected by means of XRPD were ettringite, hemicarboaluminate, portlandite, Ca-Si hydrates (C-S-H): the same occurring in real cements. The Avrami nucleation and growth model successfully fits the degree of hydration data, confirming that C-S-H should have a layered structure as well as the phases resulting from the decomposition of ettringite. The mass balance method was used to calculate the exact amount of C-S-H formed during hydration, which is not directly accessible from Rietveld refinement. The comparison between the degree of hydration calculated from isothermal calorimetry data and the degrees of hydration calculated from x-ray diffraction has revealed how much the reactant phases are responsible for heat release. In particular, it was seen that the study of C3S-C3A-Gy systems is not a simple sum of the investigations of C3S-Gy and C3A-Gy systems, which are two further simplified model cements. The synthetic materials suffered a loss on reactivity despite of the under-vacuum sealing, leading to a continuous and unpredictable change of the materials features (particle size, degree of reactivity) during time. The obtained experimental data should be necessary to proof the effectiveness of software modelling (HydratiCA). The software has been tested and returned satisfactory results for further simplified systems, such C3S-Gy. Nevertheless, the software is still under a development stage and improvements has to be planned for C3A-Gy systems before testing more complex blends
L’origine del cemento, utilizzato come legante nell’industria costruttiva, può essere attribuita direttamente ai Romani, i quali osservarono come una miscela di calcare e ceneri vulcaniche finemente macinate fosse in grado, quando miscelata con acqua, di dar luogo a presa, prima, e ad alte resistenze meccaniche, poi, in un modo così efficace mai osservato precedentemente con altri materiali. Da quando i Romani hanno dato il via all’utilizzo di leganti idraulici, diverse tipologie di cemento sono state prodotte per diversi impieghi costruttivi. Per comprendere esaustivamente i meccanismi che conducono allo sviluppo delle resistenze meccaniche, è fondamentale conoscere a fondo come procedano le cinetiche di reazione durante il processo di idratazione. La ricerca sui materiali cementizi ha oramai raggiunto risultati ragguardevoli in merito allo studio delle cinetiche chimiche ma, nonostante la lunga storia relativa a questi materiali ancora molto lavoro dev’essere svolto. I cementi miscelati con acqua formano miscele complesse che si modificano in maniera significativamente complessa, sia dal punto di vista chimico sia dal punto di vista fisico, durante il processo di idratazione. Un modello di idratazione univoco che riesca a spiegare tutte le fasi del processo di idratazione è il fine ultimo della ricerca sui materiali cementizi, sebbene questo obiettivo sia ancora lontano, a causa dei numerosi parametri chimico-fisici coinvolti. Per ovviare almeno in parte la complessità dei materiali cementizi tradizionali, per scopi scientifici vengono prodotti sistemi cementizi semplificati, caratterizzati soprattutto da un numero di fasi inferiore rispetto ad un cemento tradizionale. Un progetto di ricerca è stato messo a punto per approfondire l’aspetto delle cinetiche di reazione. Tre partner sono coinvolti: NIST (National Institute of Standards and Technology), W.R. GRACE ed Università degli Studi di Padova. La parte di progetto inerente al nostro gruppo di ricerca riguardava l’utilizzo della diffrazione in-situ di raggi X per polveri sulle paste in idratazione, utilizzando l’analisi quantitativa con il metodo Rietveld per quantificare l’andamento delle fasi nel tempo. Sono stati scelti tre diversi sistemi cementizi semplificati, formati da materiali sintetizzati in laboratorio: silicato tricalcico Ca3SiO5 (C3S), alluminato tricalcico Ca3Al2O6 (C3A) e diverso contenuto di gesso CaSO4∙2H2O (CŠH2). Sono state impiegate le tecniche di diffrazione in-situ di raggi X per polveri (XRPD) e calorimetria isoterma (IC) per valutare le cinetiche di dissoluzione e precipitazione di reagenti e prodotti. Dall’analisi qualitativa dei diffrattogrammi, i principali prodotti di idratazione individuati sono ettringite, emicarbonato, portlandite, idrati di Ca-Si (C-S-H): gli stessi prodotti di idratazione che si possono individuare nei cementi tradizionali. Il modello di nucleazione e crescita di Avrami descrive adeguatamente la curva del grado di idratazione, confermando che il C-S-H mostra una struttura a strati, come pure le fasi che derivano dalla decomposizione dell’ettringite. Il metodo del bilancio di massa è stato utilizzato per ricavare quanto C-S-H precipita durante l’idratazione, quantità che non è direttamente calcolabile neanche attraverso l’analisi quantitativa col metodo Rietveld. Confrontando la curva del grado di idratazione calcolato dalla calorimetria isoterma e le curve del grado di idratazione ricavate dai dati in diffrazione rivelano le fasi che qualitativamente e quantitativamente sono maggiormente implicate nello sviluppo di calore. In particolare, si è visto che lo studio dei sistemi C3S-C3A-Gy non coincide con la “somma algebrica” dei risultati sugli studi di C3S-Gy e C3A-Gy (due sistemi cementizi ulteriormente semplificati). I materiali di partenza hanno subito una perdita di reattività, nonostante siano stati conservati sottovuoto. La perdita di reattività ha di fatto modificato continuamente i materiali, cambiando spesso le condizioni iniziali (distribuzione granulometrica, grado di reattività) portando a risultati non facilmente prevedibili. I risultati ottenuti sperimentalmente dovrebbero essere propedeutici per provare l’efficacia del software di modellazione (HydratiCA). Il software è stato provato sul sistema C3S-Gy, fornendo risultati incoraggianti. Tuttavia, tale software, essendo ancora in fase di sviluppo, necessita di miglioramenti soprattutto per quanto riguarda il sistema C3A-Gy, prima di poter passare alla simulazione di miscele più complesse

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Blanc, Caroline. "Etude des auto-anticorps anti-Facteur H dans le Syndrome Hémolytique et Urémique atypique et dans la glomérulonéphrites membrano-prolifératives." Paris 7, 2012. http://www.theses.fr/2012PA077003.

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Deux maladies rénales sont liées à une dérégulation du complément : le SHUa et la GNMP. La forme auto-immune du SHUa est liée à la présence d'auto-anticorps dirigés contre le Facteur H, également retrouvés dans des GNMP. La forme de SHUa-AI est caractérisée par la présence de complexes immuns circulants, une perturbation de la protection membranaire par le FH et de son interaction avec ses ligands protéiques, non retrouvées chez les patients atteints de GNMP. Les sites de liaison au FH sont différents, les anticorps associés au SHUa reconnaissent les régions N- et C-terminales tandis que les anticorps associés à une GNMP que la région N-terminale. Le déficit complet d'une protéine structurellement proche du FH (CFHR1) n'est associé qu'à la forme de SHUa-AI et pourrait jouer un rôle dans la génération et la pathogénicité des anticorps anti-FH. L'étude in silico des épitopes potentiellement présentés par HLA-A24 a révélé une possible cross-réactivité avec des protéines parasitaire, compatible avec l'étude clinico-biologique des patients atteints de SHUa-AI. Nos données suggèrent l'existence de mécanismes d'auto-immunisation liés à une perte de tolérance par deletion d'un gène et d'une réaction croisée avec une réponse anti-parasitaire chez ces patients atteints de SHUa. Dans la GNMP, les anticorps anti-FH sont fréquemment associés à un anticorps anti-C3 convertase ou à une immunoglobuline monoclonale révélant des mécanismes d'immunisation plus hétérogènes. Ces résultats permettent de mieux comprendre les différences physiopathologiques entre le SHUa et la GNMP, et pourraient révéler de nouveaux concepts généraux d'immunisation dans le cadre de maladies auto-immunes
Dysregulation of the complement System is linked to two different renal diseases: aHUS and MPGN The autoimmune form of aHUS is due to generation of autoantibodies directed Factor H. Moreover, we have characterized anti-FH IgG in patients presenting with MPGN. AI-aHUS patients had increased levels of FH-containing immune complexes and perturbation of FH-dependent cell-protection, in contrast to MPGN patients. AI-aHUS associated antibodies bound both N-and C-terminal domains of FH, while in case of AI-MPGN they bound the FH N-terminal domain only. The homozygous deletion of Factor H related protein CFHR1 is strongly associated with AI-aHUS and may play a role in the underlying mechanisms of anti-FH autoantibodies generation and in their pathological role. An in silico prediction of the epitopes potentially presented by the HLA-A24 was conducted and revealed a high sequence similarity between FH-derived peptides and peptides of a parasitic origin, correlated with the analysis of the clinical and biological symptoms of the AI-aHUS. Taken together, these results suggested that the mechanisms underlying the auto-immunization are related to a loss of tolerance due to a deletion of a FH homologous gene and a cross-reactivity towards a parasite antigen in AI-aHUS. In MPGN, anti-FH antibodies are frequently associated to monoclonal gammopathy or with other autoantibodies, directed against and stabilizing the C3 convertase, therefore revealing more heterogeneous mechanisms of immunization. These results led to a better understanding of the pathophysiological differencies between aHUS and MPGN. They could also reveal new auto-immunization scenario in autoimmune diseases

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Maniyar, Abhishek Sanjay. "From the CMB to CIB : dusty star formation, dark energy and kSZ." Thesis, Aix-Marseille, 2019. http://theses.univ-amu.fr.lama.univ-amu.fr/190919_MANIYAR_759uunye462vklkb421iixa572jct_TH.pdf.

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Le fond diffus infrarouge (CIB) provient de l'émission IR cumulée des galaxies sur toute l'histoire de l'Univers. Ainsi, le CIB sonde la formation et l'évolution des galaxies sur une grande gamme de décalage vers le rouge. Dans cette thèse, nous utilisons les anisotropies du CIB pour: i) Mesurer l'histoire de la formation des étoiles de l'Univers et le biais effectif des halos de matière noire hébergeant les galaxies CIB jusqu'à un décalage rouge élevé. En utilisant ces mesures, nous calculons la masse typique de ces halos de matière noire, sur une grande gamme de décalage vers le rouge. ii) En utilisant le CIB comme traceur de la structure à grande échelle, la corrélation croisée avec le CMB fournit une sonde alternative de l'énergie noire. Nous montrons que le CIB, extrait sur une grande fraction du ciel, peut fournir la meilleure mesure de l'effet ISW. En utilisant un formalisme matriciel de Fisher, nous prédisons l'amélioration des contraintes sur les paramètres cosmologiques en utilisant l'ISW mesuré avec le CIB. iii) Mesurer le spectre de puissance de l'effet Sunyaev-Zel'dovich cinétique (kSZ) caché dans les données du CMB. Nous améliorons les analyses existantes en combinant les mesures du CIB (de Planck/HFI et Herschel/SPIRE) et les observations de Planck, SPT et ACT pour étendre la gamme des échelles spatiales et des fréquences afin de faciliter la mesure du kSZ. Nous développons un nouveau modèle pour le CIB (pour pouvoir tenir compte des petites échelles spatiales), et modélisons de façon cohérente l'effet SZ thermique (tSZ) et la corrélation CIBxtSZ. Ceci est nécessaire pour séparer avec précision ces différentes composantes dans le spectre de puissance
The CIB is the cumulative infrared emission from all the galaxies throughout cosmic history. Its distinct frequency-redshift dependence allows to probe a large span of redshifts. In this thesis, we utilise the CIB anisotropies detected by the Planck satellite to:i) Measure the star formation history of the Universe and the effective bias of the dark matter halos hosting the CIB galaxies to a high redshift. Using these measurements, we calculate the typical mass of the host dark matter halos for the CIB galaxies at different times.ii) Using the CIB as a tracer of the large scale structure, the cross-correlation with the CMB provides with an alternative probe of the dark energy. We showed that the CIB, extracted on a large fraction of the sky, may provide the best Integrated Sachs Wolf measurement (in terms of S/N ratio). Using a Fisher matrix formalism, we also predict the improvement on the constraints on the cosmological parameters using the ISW measured with this technique. We cross-correlate the best available maps of the CIB and the CMB and find that the dust residuals in the CIB maps are too high to detect the ISW through this method.iii) Measure the kinetic Sunyaev-Zel'dovich (kSZ) power spectrum hidden in the CMB power spectrum. We improve upon the existing analysis by combining the CIB measurements (from Planck/HFI and Herschel/SPIRE) and multi-frequency observations by Planck, SPT and ACT to extend the range of scales and frequencies to facilitate the kSZ measurement. We develop a power spectrum analysis based on physically motivated but simplistic and consistent models of foreground components (CIB, tSZ, tSZxCIB) to accurately separate the kSZ from the CMB

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Aydin, Gunay Semra. "Influence de la cinétique d'hydratation des phases aluminates en présence de sulfate de calcium sur celles des phases silicates : conséquences sur l'optimum de sulfatage des ciments." Thesis, Dijon, 2012. http://www.theses.fr/2012DIJOS007/document.

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Les propriétés mécaniques des ciments hydratés nécessitent d'être optimisées suivant la nature des ciments produits. Parmi les facteurs d'optimisation, l'ajout de sulfate de calcium destiné à réguler la réactivité de l’aluminate tricalcique (C3A), en quantité et en qualité, dans le ciment est un paramètre primordial. Enjeu industriel majeur, cette notion d'Optimum de sulfatage mérite aujourd'hui du fait de l'avancement des connaissances sur les mécanismes d'hydratation de chacune des phases du ciment qu'une étude lui soit entièrement consacrée. La démarche adoptée pour répondre à cette problématique a été l’étude de système simple que l’on a compliqué petit à petit. L’évolution de l’hydratation du ciment, de la porosité et des propriétés mécaniques du ciment ont été déterminés à différentes échéances. Le premier système étudié était le mélange C3S/gypse, l'objectif était de déterminer s'il existait un effet optimal du sulfate de calcium sur l'hydratation et les résistances mécaniques du C3S tel que présenté dans la littérature [1]. Les résultats ont montré qu’il n’existait pas d’optimum de sulfatage dans le système C3S/gypse mais qu’il existait un effet spécifique du sulfate de calcium sur l’hydratation et les propriétés mécaniques du C3S. L’adsorption des sulfates à la surface des C-S-H serait à l’origine de la modification du processus de germination croissance des C-S-H qui aurait pour conséquence l’augmentation du degré d’hydratation du C3S et des résistances en compression. Le deuxième système étudié était le clinker biphasique C3S/C3A cobroyé avec du semi-hydrate et avec du gypse. Un optimum de sulfatage a bien été observé, cet optimum se décale avec le temps vers les fortes teneurs en sulfate comme dans les cimenteries. L’optimum de sulfatage a été constaté lorsque l’hydratation du C3S, pendant la période accélérée, a lieu simultanément ou légèrement avant le pic exothermique dû à la forte dissolution du C3A et à la précipitation d’Afm. Il a été montré que la présence d’AFm pendant la période accélérée de l’hydratation du C3S, serait à l’origine de la modification observée de la microstructure de la pâte de ciment : la porosité augmente avec l’ajout du sulfate de calcium mais l’assemblage des hydrates est plus dense
The mechanical properties of hydrated cements need to be optimized according to the nature of cement products. Among the factors of optimization, the addition of calcium sulphate intended to regulate the reactivity of tricalcium aluminate (C3A), in quantity and quality in cement is an essential parameter.The advancement of knowledge on the mechanisms of hydration of each cement phase allows a study devoted entirely to the concept of optimum of sulphate. We studied simple system that we complicated and we studied the evolution of hydration, porosity and mechanical properties of cement at different age. The first system studied was the mixture C3S/gypsum, the objective was to determine whether there was an optimal effect of calcium sulfate on hydration and mechanical strength of C3S as presented in the literature [1]. The results showed there was not optimum sulfate in the C3S/gypsum system but there was a specific effect of calcium sulfate on the hydration and the mechanical properties of C3S. The sulfate adsorption on the C-S-H surface is the cause of the change nucleation and growth process of C-S-H. This has resulted in increasing hydration degree of C3S and compressive strength. The second system studied was biphasic clinker C3S/C3A ground with hemi-hydrate and gypsum. An optimum sulfate has been observed, which move out with time to high rate of sulfate. The optimum sulfate was observed when the hydration of C3S, during the accelerated period, takes place simultaneously or slightly before the exothermic peak due to the high dissolution of C3A and precipitation of AFm. We showed the presence of AFm during the accelerated hydration of C3S, is the cause of the microstructure modification in the cement paste: the porosity increases with calcium sulfate addition but the hydrate assembly is more dense

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Li, K. "Interactions of complement receptor type 2 with C3d and factor H with C3u." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/769696/.

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Complement receptor type 2 (CR2, CD21) is a cell surface protein that links the innate and adaptive immune response through its binding to C3d, a cleavage fragment of the major complement component C3. Factor H (FH) is a major plasma protein that is the major regulator of the activity of C3b in the alternative pathway. FH binds to C3u, which is formed from C3 by hydrolysis, and C3u shows functional similarities to C3b. In this thesis, X-ray scattering, analytical ultracentrifugation and constrained modelling were used to determine solution structures and interactions of CR2 with C3d and FH with C3u. Structural studies reveal that the overall CR2 structure is unaffected by change in ionic strength or when C3d is bound to it. Unbound C3d exists in monomerdimer and monomer-trimer equilibria in low salt buffer, but as a monomer only in physiological buffer. The CR2-C3d interaction is not formed in physiological salt conditions, but was observed in low salt conditions. The solution structure and selfassociation of C3u were investigated. C3u underwent weak salt-dependent dimerisation, similar to that for C3d. Modelling showed that the functionally-important TED/CUB domains in the C3d part of C3u were extended away from the rest of the C3u structure. This TED/CUB conformation is intermediate between those of C3 and C3b. C3u and FH were observed to interact as 1:1 and 2:1 complexes in a salt-dependent manner. The modelling of the interaction showed that no major conformational changes occurred in C3u or FH, and suggested that C3u binds separately to FH at two independent sites. These results provide new insights in the activation of C3 and the complement regulatory activity of CR2 and FH.

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Leoratti, Fabiana Maria de Souza. "Influência de variantes de receptores de reconhecimento padrão na suscetibilidade à malária." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-19112008-173242/.

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Malária é uma das principais causas de doença e morte no mundo, principalmente de crianças. É considerada a força de seleção evolucionária mais forte que se conhece na história recente do genoma humano. Além dos fatores ambientais e do próprio parasito, fatores genéticos do hospedeiro têm um papel fundamental tanto na suscetibilidade como na evolução clínica da infecção. O sistema imune inato reconhece os plasmódios através de um número limitado de receptores de reconhecimento padrão (PRRs) e inicia vários mecanismos de defesa que resultam no desenvolvimento de inflamação e resistência do hospedeiro à infecção. Mas, a eliminação completa do parasito requer respostas imunes adaptativas que são amplificadas pela ativação do sistema imune inato. As manifestações clínicas de malária são dependentes dos níveis de citocinas próinflamatórias circulantes produzidas, as quais em níveis altos contribuem para a imunopatologia da doença. O balanço entre respostas pró e antiinflamatórias dirigidas contra o parasito é considerado crítico para a proteção clínica, assim a resposta imune inata pode contribuir tanto para proteção da malária como para modular a resposta imune adaptativa. Neste estudo, nós investigamos polimorfismos de um único nucleotídeo (SNP) dos genes de três PRRs: TLR, MBL e CR1 de indivíduos infectados por Plasmodium e residentes em áreas endêmicas de malária no Brasil. Os SNPs TLR1 (I602S), TLR4 (D229G), TLR6 (S249P), TLR9 (T-1237C/ -1486C), MBL [exon 1 nos códons 52, 54, e 57 (MBL2*A ou D, A ou B e A ou C, respectivamente); na região do promotor na posição -221 (*X ou *Y); e na posição +4 da região não traduzida (*P ou *Q)] e CR-1(C5507G) foram determinados por PCR-RFLP. Nós observamos associações entre os polimorfismos TLR1 I602S, TLR6 S249P e da região não traduzida +4 (*Q) e manifestações clínicas de malária e entre os polimorfismos TLR9 T-1486C, TLR T-1237C, MBL*D (códon 52) e do diplótipo de produção insuficiente de MBL (XA+O/O) e parasitemias mais altas. Nenhuma associação foi observada entre o polimorfismo CR-1 C5507G e manifestações clínicas de malária ou com parasitemia. Ao analisarmos juntos os polimorfismos de MBL e TLR, observamos que indivíduos com diplótipo de produção suficiente de MBL (YA/YA+YA/XA+YA/O+XA/XA) TLR1 I602S tinham menos manifestações clínicas de malária e indivíduos com diplótipo de produção suficiente de MBL e não carreadores do alelo TLR9 -1486C tinham parasitemias mais baixas do que os indivíduos com diplótipo de produção insuficiente de MBL e carreadores dos alelos variantes de TLR1 I602S e TLR9 -1486C, respectivamente. Juntos, nossos dados indicam que polimorfismos do promotor de TLR-9 e os diplótipos de produção insuficiente de MBL (XA+O/O) devem de algum modo controlar o nível de parasitemia por plasmódios enquanto a deficiência de TLR1 parece predispor para a presença de manifestações clínicas de malária. Também, podemos sugerir que existe uma cooperação entre TLR1, TLR9 e MBL na ativação da resposta imune inata na malária. Estes achados genéticos devem contribuir para o entendimento da patogênese da malária e levantar uma questão potencialmente interessante que é digna de investigações posteriores em outras populações a fim de validar a contribuição genética destes loci na patogênese da malária
Malaria is one of the major causes of disease and death worldwide, mainly of children. It is also the strongest known force for evolutionary selection in the recent history of the human genome. Besides environmental and parasite factors, host genetic factors play a major role in determining both susceptibility to malaria and the course of infection. Innate immune mechanisms directed against Plasmodium parasites both contribute to protection from malaria and modulate adaptive immune responses. The innate immune system recognizes Plasmodium via a limited number of pattern-recognition receptors (PRRs) and initiates a broad spectrum of defense mechanisms that result in the development of inflammation and host resistance to infection. But, the complete control of the infection requires adaptive immune responses; and the innate immune system is also very efficient in instructing the cellular mediators of adaptive immunity to lead a powerful additional strike force against the parasite. Clinical malaria is characterized by high levels of circulating proinflammatory cytokines, which are thought to contribute to the immunopathology of the disease. The balance between pro- and anti-inflammatory responses toward the parasite is considered critical for clinical protection. The innate immune system initiates and thus sets the threshold of immune responses. In this study, we investigated single nucleotide polymorphisms (SNP) in the genes of three PRRs: TLR, MBL and CR1 in Plasmodium-infected individuals living in endemic areas of Brazil. The SNPs TLR1 (I602S), TLR4 (D229G), TLR6 (S249P), TLR9 (T-1237C/ -1486C), MBL [in the coding sequence of exon 1 at codons 52, 54, and 57 (MBL2*A or D, A or B, and A or C, respectively); in the promoter region at position -221 (*X or *Y); and in the untranslated sequence at position +4 (*P or *Q)] and CR-1(C5507G) were determined by PCR-RFLP. We observed associations of the TLR1 I602S, TLR6 S249P and untranslated sequence at position +4 MBL (*Q) variants with clinical manifestations of malaria and of the TLR9 T-1486C, TLR9 T-1237C, MBL2*D and MBL-insufficient diplotype (XA+O/O) with higher parasitemias. No association was observed to the CR-1 C5507G ) and clinical manifestations of malaria or parasitemia. Also, we observed that individuals with MBLsufficient haplotype (YA/YA+YA/XA+YA/O+XA/XA) and not bearing the allele TLR1 I602S had less clinical manifestations of malaria and individuals with MBL-sufficient haplotype and not bearing TLR9 -1486C had lower parasitemias when compared to individuals with MBL-insufficient diplotype and bearing the variant alleles TLR1 I602S and TLR9 -1486C, respectively. Altogether, our data indicate that TLR-9 promoter and MBL-insufficient haplotype (XA+O/O) polymorphisms to some extent may control the level of Plasmodium parasitemia while TLR1 deficiency seems to predispose to mild malaria. Also, they could suggest cooperation among TLR1, TLR9 and MBL in the immune response against malaria. These genetic findings may contribute to the understanding of the pathogenesis of malaria and raise a potentially interesting issue that is worthy of further investigation in other population in order to validate the genetics contribution of these loci to the pathogenesis of malaria

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Verger, Denis. "Etude cristallographique préliminaire de la région globulaire de C1q et d'un fragment de C3 du complément humain : structures cristallines de complexes entre la subtilisine de Bacillus lentus et des inhibiteurs de type acide boronique." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10097.

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C1q initie la voie classique du complement grace a sa region globulaire (gr). C3de correspond a la partie de c3b qui se fixe sur les cellules cibles. Nous avons cristallise ces proteines et enregistre un jeu de donnees a 3,2 a pour la gr, a 3,7 a pour c3de. Des problemes de reproductibilite et de taille des cristaux nous ont empeche de poursuivre l'etude. La subtilisine de bacillus lentus (savinase#t#m) est utilisee comme additif dans les detergents des lessives. Des inhibiteurs competitifs et reversibles (acides boroniques) sont ajoutes dans ces solutions pour eviter que la savinase#t#m ne degrade les autres enzymes presentes. Nous avons resolu la structure de 4 complexes a 2 a puis 1,7 a par remplacement moleculaire a partir d'une nouvelle forme cristalline. Les acides boroniques interagissent avec la proteine par une liaison covalente entre leur atome de bore et l'oxygene gamma de la serine active, et par des contacts hydrophobes entre leur groupement r et la poche de specificite s1. L'acide benzo furane 2 boronique (bf2ba) est l'inhibiteur le plus efficace parmi les 4 etudies. La reactivite entre le bore et la serine active depend de la nature du groupement r, du ph, de la concentration en inhibiteur. A partir du modele savinase#t#m/bf2ba, nous proposons des inhibiteurs potentiellement plus efficaces

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Minard, Hélène. "Etude intégrée des processus d'hydratation, de coagulation, de rigidification et de prise pour un système C3S-C3A - sulfates - alcalins." Dijon, 2003. http://www.theses.fr/2003DIJOS049.

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L'objectif de ce travail est d'étendre la validité des concepts développés au Laboratoire pour l'hydratation et la prise du système simple: le silicate tricalcique ou alite (principal composant du ciment Portland) au cas d'un système plus complexe, proche d'un ciment réel, constitué d'un mélange de phases pures: l'alite et l'aluminate tricalcique, auxquelles sont ajoutés du gypse (sulfates) et des alcalins. L'étude systématique de l'hydratation des pâtes de mélanges modèles, par microcalorimétrie isotherme, montre qu'il existe de fortes interactions entre les différents constituants. La notion de "rendement mécanique des hydrosilicates de calcium" permet d'évaluer l'influence des autres constituants que l'alite sur les propriétés élastiques des pâtes de mélanges. Le rendement mécanique des mélanges alite-aluminate tricalcique est accru en présence de gypse et en présence d'alcalins
The aim of this work is to use a similar approach developed in Laboratory for the hydration and the setting of simple system : the tricalcium silicate or alite (the most important composant of Portland cement) to a system more complex, close to a real cement, composed of a mixture of pures phases : alite and tricalcium aluminate, which are added gypsum and alkalines. The hydration study, by isotherm microcalorimetry, of pastes of models mixtures shows that strong interactions exist between different constituants. The "mecanic yield of calcium hydrosilicates" notion allows the evaluation of the influence of constituants different from alite, on the elastic properties of pastes of mixtures. The mecanic yield of mixtures of alite and tricalcium aluminate increase in presence of gypsum and alkalines

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Grisin, Aleksandr. "Diastereoselective synthesis of syn-1,3-polyols and studies towards the C1-C31 and C32-C52 fragments of amphidinol 3." Thesis, University of Liverpool, 2012. http://livrepository.liverpool.ac.uk/10373/.

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Diastereoselective Synthesis of syn-1,3-Polyols The stereoselective construction of polyacetate 1,3-diols has attracted considerable attention due to the ubiquity of this motif in complex biologically active polyene macrolides (amphotericin B, RK-397, mycoticin, candidin). We have developed a highly stereoselective bismuth(III)-mediated two-component hemiacetal/oxa-conjugate addition reaction, which directly provides syn-1,3-diols in the form of cyclic acetals having an adjacent electron-withdrawing group in the form of aldehydes and ketones. The scope and limitations of this transformation were examined and culminated with the synthesis of the C18-C28 fragment of antibiotic RK-397. Studies towards the C1-C31 and C32-C52 Fragments of Amphidinol 3 Temporary-tethered reactions provide an important strategy for target- directed synthesis, since they circumvent the problems encountered with entropically unfavorable reactions. The temporary silicon-tethered ring-closing metathesis (TST- RCM) allows for the highly (Z)-selective coupling of mixed silaketals in the formation of the medium sized rings. The latter compounds can undergo a substrate controlled stereoselective electrophilic functionalisation, for example, hydroboration, dihydroxylation or epoxidation, and produce polyoxygenated motifs that are present in many biologically important natural products. In the course of these studies we have developed a highly convergent asymmetric synthesis of the C1-C31 polyol fragment of amphidinol 3, where the TST-RCM/hydroboration reaction is successfully employed for the efficient coupling ii of the C16-C23 and C24-C30 units of the natural product with concomitant introduction of the crucial propionate-type C23-C24 stereocentres. In the final part of thesis the investigation of the stereoselective dihydroxylation reaction of mixed syn and anti eight-membered cyclic silaketals was carried out. The resulting oxygenated products can be efficiently transformed via an intramolecular cyclisation of δ-hydroxy epoxides into the highly substituted syn- and anti-tetrahydropyrans (THPs), a strategy that could also have application in related natural products, for example, ladder polyether polyketides. The merit of the developed methodology was highlighted in the asymmetric synthesis of the common C31(52)-C39(44) THP fragment of amphidinol 3, which could be ultimately used in the bidirectional route towards the bis-THP segment of the natural product.

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Ptchelkine, Denis. "Etudes structurales sur le complexe spécifique de l’arn polymérase III C82/C34/C31 et le facteur de transcription végétal Leafy." Université Joseph Fourier (Grenoble), 2008. http://www.theses.fr/2008GRE10236.

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Dans cette thèse deux sujets sont abordés. Dans la première partie de thèse les résultas de la caractérisation structurale du sous-complexe C82/C34/C3l obtenus pendant les deux premières années de ma thèse sont présentés. La plupart des expériences effectuées pendant cette période avaient pour but la production de cristaux du sous-complexe qui auraient servi pour la collection des données de diffraction. Dans ma thèse, je décris différentes approches pour la production du sous-complexe et pour la cristallisation. Malheureusement, les cristaux du sous-complexe n'ont jamais été obtenus. La deuxième partie de mon travail portait sur la caractérisation biochimique et structurale du complexe C82/C34/C31. Une analyse des données biochimiques sur l'interaction entre la sous-unité C34 et des composants du complexe TFIIIB est exposée en détail. Dans la deuxième partie de cette thèse je décris l'étude structurale du facteur de transcription végétal LEAFY par cristallographie aux rayons X. En collaboration avec l'équipe de Dr. François Parcy (CEA, Grenoble), nous avons obtenu la structure de ce facteur de transcription en complexe avec deux fragments d'ADN des promoteurs APl et AG-I avec des résolutions de 2. 1 et 2. 3Â. Ces structures ont permis d'établir les déterminants majeurs de la reconnaissance spécifique de l'ADN par LFY. Une liaison coopérative des deux monomères de LFY au site APl et AG-I explique en partie la fonction de LFY comme un déclencheur de la transition du méristème vers son état déterminé
The first part of my thesis describes my work on the RNA polymerase III specific subcomplex. Since the first studies on the subcomplex C82/C34/C3l there were a number of functional studies on this subcomplex that revealed its involvement in the transcription pre initiation process. During my thesis 1 tried to advance more deeply into the understanding of this process from the structural point of view by X-ray crystallography. Although no crystals of the subcomplex could be obtained, a wealth ofvaluable results have been gathered on different strategies of co-expression of the components of the subcomplex and the crystallization approaches that 1 have explored during my thesis. On the other hand, 1 established the minimal interacting parts of the proteins in the C82/C34/C3l subcomplex and in the TFIIffi complex. One of the most intriguing pro cesses in plant development is the switch from the vegetative into generative growth. LEAFY (LFY) is a key player in this transition as it integrates signaIs from multiple pathways and induces the differentiation of the floral meristem. On the other hand, LFY is found in non-flowering plants, in which it controls the key transitions in the plant life cycle. Ln spite of a number of genetics studies on LFY, The function of LFY on the molecular level remained elusive until now. Ln collaboration with the group ofF. Parcy (CEA, Grenoble) we solved the crystal structure of the LFY DNA binding domain in complex with two different DNA fragments bearing the sequences from the AP-l and AG-I promoters recognized by LFY. This work is presented in the second part of the thesis

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Proctor, Lavinia M. "Pharmacological activity of C3a and C3a receptor ligands /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18423.pdf.

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Pedrazzi, Pietro. "Studio della sostenibilità ambientale nel ciclo di vita di un edificio in terra cruda in Mali." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21503/.

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Questa tesi mira a valutare la sostenibilità ambientale ed economica di una scuola di tre classi, costruita in mattoni di terra cruda compressa a Dougourakoro, in Mali, seguendo i principi della progettazione bioclimatica. A questo scopo, è stata condotto uno studio LCA che compara due diversi casi di studio: l’edificio bioclimatico in mattoni compressi di terra cruda ed un edificio in mattoni forati di cemento, che rispecchia la tipologia costruttiva maggiormente diffusa localmente. L’utilizzo della terra cruda come materiale da costruzione, infatti, è stato localmente soppiantato negli ultimi decenni da mattoni in cemento che necessitano di una minore manutenzione. I risultati dell’analisi LCA indicano un minore impatto ambientale dell’edificio in terra cruda, che si crede possa essere ulteriormente accentuato da una futura inclusione nell’analisi della fase di uso. I maggiori costi che è necessario sostenere durante la costruzione corrispondono ad una maggiore quantità dei materiali utilizzati e ad una superiore complessità delle lavorazioni durante la costruzione. Sintetizzando i risultati, si conclude che, nonostante l’edificio in terra cruda abbia un minore impatto ambientale, il potenziale inespresso di questo materiale è ancora altissimo, potendo manifestarsi appieno, però, solo dopo una rinnovata accettazione sociale, stimolata attraverso attività formative in loco che potrebbero portare ad una maggiore diffusione di conoscenze, conoscenze e macchinari legati a questo materiale, abbattendone così, i costi di produzione e costruzione.

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GULOTTA, Maria Rita. "Computational methodologies applied to Protein-Protein Interactions for molecular insights in Medicinal Chemistry." Doctoral thesis, Università degli Studi di Palermo, 2021. http://hdl.handle.net/10447/479127.

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In living systems, proteins usually team up into “molecular machinery” implementing several protein-to-protein physical contacts – or protein-protein interactions (PPIs) – to exert biological effects at both cellular and systems levels. Deregulations of protein-protein contacts have been associated with a huge number of diseases in a wide range of medical areas, such as oncology, cancer immunotherapy, infectious diseases, neurological disorders, heart failure, inflammation and oxidative stress. PPIs are very complex and usually characterised by specific shape, size and complementarity. The protein interfaces are generally large, broad and shallow, and frequently protein-protein contacts are established between non-continuous epitopes, that conversely are dislocated across the protein interfaces. For this reason, in the past two decades, PPIs were thought to be “undruggable” targets by the scientific research community with scarce or no chance of success. However, in recent years the Medicinal Chemistry frontiers have been changing and PPIs have gained popularity amongst the research groups due to their key roles in such a huge number of diseases. Until recently, PPIs were determined by experimental evidence through techniques specifically developed to target a small group of interactions. However, these methods present several limitations in terms of high costs and labour- and time-wasting. Nowadays, a large number of computational methods have been successfully applied to evaluate, validate, and deeply analyse the experimentally determined protein interactomes. In this context, a high number of computational tools and techniques have been developed, such as methods designed to construct interaction databases, quantum mechanics and molecular mechanics (QM/MM) to study the electronic properties, simulate chemical reactions, and calculate spectra, and all-atom molecular dynamics simulations to simulate temporal and spatial scales of inter- and intramolecular interactions. These techniques have allowed to explore PPI networks and predict the related functional features. In this PhD work, an extensive use of computational techniques has been reported as valuable tool to explore protein-protein interfaces, identify their hot spot residues, select small molecules and design peptides with the aim of inhibiting six different studied PPIs. Indeed, in this thesis, a success story of in silico approaches to PPI study has been described, where MD simulations, docking and pharmacophore screenings led to the identification of a set of PPI modulators. Among these, two molecules, RIM430 and RIM442, registered good inhibitory activity with IC50 values even within the nanomolar range against the interaction between MUC1 and CIN85 proteins in cancer disease. Furthermore, computational alanine scanning, all-atom molecular dynamics simulations, docking and pharmacophore screening were exploited to (1) rationally predict three potential interaction models of NLRP3PYD-ASCPYD complex involved in inflammatory and autoimmune diseases; (2) identify a potentially druggable region on the surface of SARS-CoV-2 Spike protein interface and select putative inhibitors of the interaction between Spike protein and the host ACE2 receptor against COVID-19 (CoronaVIrus Disease 2019); (3) investigate intramolecular modifications as a consequence of a point mutation on C3b protein (R102G) associated with the age-related macular degeneration (AMD) disease; (4) design non-standard peptides to inhibit transcriptional events associated with HOX-PBX complex involved in cancer diseases; and (5) to optimise a patented peptide sequence by designing helix-shaped peptides embedded with the hydrogen bond surrogate approach to tackle cocaine abuse relapses associated with Ras-RasGRF1 interaction. Although all the herein exploited techniques are based on predictive calculations and need experimental evidence to confirm the findings, the results and molecular insights retrieved and collected show the potential of the computer-aided drug design applied to the Medicinal Chemistry, guaranteeing labour- and time-saving to the research groups. On the other hand, computing ability, improved algorithms and fast-growing data sets are rapidly fostering advances in multiscale molecular modelling, providing a powerful emerging paradigm for drug discovery. It means that more and more research efforts will be done to invest in novel and more precise computational techniques and fine-tune the currently employed methodologies.

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Rossi, Urquijo Javier, and Arnaldo Cano. "Advantage in Cab." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/147743.

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TESIS PARA OPTAR AL GRADO DE MAGÍSTER EN ADMINISTRACIÓN
Javier Rossi Urquijo [Parte I Análisis estratégico y de mercado], Arnaldo Cano [Parte II Análisis organizativo y financiero]
AdVantage in Cab, es un proyecto innovador que busca hacer converger tanto la evolución tecnológica en la que se encuentra la sociedad actualmente y las necesidades de 2 actores claves para el desarrollo adecuado del proyecto. Posesionados desde la demanda, se detecta la necesidad de modernización y asesoría tecnológica de los gremios de taxis convencionales incluyendo en su oferta soluciones tecnológicas como la propuesta. Por otra parte, y para poder financiar la propuesta, se detecta la necesidad creciente de las agencias publicitarias de poder segmentar cada vez con mayor exactitud, las exposiciones de sus campañas. Dado lo anterior, AdVantage in Cab ofrece una plataforma para difusión publicitaria al interior de los taxis convencionales, a través de Tablet instaladas en la parte posterior del asiento del copiloto, la cual proyecta campañas dependiendo del sector y el pasajero que contrata el servicio de transporte. Dicha Tablet es capaz de realizar una estimación de sexo y rango etario del pasajero con la finalidad de segmentar posteriormente la publicidad emitida y direccionar lo que las agencias necesiten. El análisis de la industria entrega resultados favorables, lo que, complementado con el aumento en la inversión en publicidad digital en Chile, que en la última década pasó de 1,4 a 14,7% del total invertido, aumenta las posibilidades de éxito. En cuanto al análisis financiero se aprecia un horizonte de maduración del negocio de 5 años, logrando al año 3 un VAN estimado de $11 MM.

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Dole, Herve. "La nuit n'est pas noire: le rayonnement de fond extragalactique et l'évolution des galaxies infrarouges." Habilitation à diriger des recherches, Université Paris Sud - Paris XI, 2010. http://tel.archives-ouvertes.fr/tel-00529539.

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L'Univers, en dehors de notre Galaxie, est baigné de nombreux rayonnements, le principal étant observable dans le domaine des ondes radio centimétriques et millimétriques: le fond cosmologique (ou CMB pour {\it Cosmic Microwave Background}), corps noir de température actuelle 2.7 Kelvin. Découvert dans les années soixante, et largement étudié depuis pour ses infimes fluctuations de température et de polarisation, il se propage librement depuis une époque située environ 400000 ans après le big-bang. Il nous renseigne sur l'état de l'Univers primordial, sur son contenu, ainsi que sur certains processus physiques ayant eu lieu ultérieurement, comme la réionisation ou la formation des amas de galaxie. Un autre rayonnement d'importance cosmologique a été découvert il y a seulement quatorze ans dans les données du satellite COBE, mais ici dans le domaine de l'infrarouge lointain, vers 200 microns de longueur d'onde: le {\bf rayonnement fossile des galaxies}, ou fond diffus extragalactique infrarouge. Il est environ 50 fois moins intense que le fond cosmologique (pic à pic, ou de 20 à 40 fois moins en intégrale). Cette détection a constitué une grande surprise vu la grande intensité relative de l'infrarouge lointain par rapport à la partie visible provenant directement des étoiles. Ce fond diffus a pour origine l'émission de toutes les galaxies depuis leur formation, et résume ainsi toute leur histoire. Il est donc permis d'écrire, presque sans ironie, que {\bf la nuit n'est pas noire}, dans la mesure où, si nos yeux (avec le concours d'une hypothétique fenêtre atmosphérique) étaient sensibles aux rayonnements infrarouge lointain, millimétrique et centimétrique, ils verraient une nuit brillante de rayonnements cosmologiques. Notons que la question de la nuit noire - connue sous le nom de paradoxe d'Olbers Chéseaux - est ancienne, fertile, et touche aux fondements de la description et la compréhension de notre Univers physique, de son origine et de son évolution. Mesurer précisément ce rayonnement de fond infrarouge et comprendre la nature des galaxies qui en sont à l'origine et leur évolution, constituent l'une des thématiques importantes de la cosmologie observationnelle d'aujourd'hui. Je détaille, dans ce manuscrit de HDR, quelques-unes de mes contributions à l'étude statistique des galaxies infrarouges, à la mesure et l'interprétation du rayonnement extragalactique, et esquisse quelques perspectives. Le document de la HDR -- soutenue le 21 septembre 2010 à l'Institut d'Astrophysique Spatiale, Orsay -- et ses annexes sont disponibles en ligne sur http://www.ias.u-psud.fr/dole/hdr/

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Dunkel, Ralf. "Asymmetrische Synthese der C17-C23 und C31-C37 Segmente von Spongistatin 1, de novo Synthese von C-Glycosid-Vorläufern und [beta]-C-Glycosiden [Beta-C-Glycosiden]." [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=957653050.

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Alves, Delma Pegolo. "Infecção pelo Cryptosporidium sp., linhagem humana MMC, em camundongos C.B-17/Uni scid, C57BL/6/Uni bg, C3H/Uni nu e C57BL/6 KO para INF-'gama'." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317886.

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Orientador: Ana Maria Aparecida Guaraldo
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Cryptosporidium é um protozoário oportunista que causa diarréia em indivíduos imunocompetentes e imunodeficientes. A duração e severidade dos sintomas clínicos dependem do sistema imunológico do hospedeiro. Nas pessoas imunocompetentes, a infecção pode ser as sintomática ou induzir uma diarréia autolimitante, enquanto nos indivíduos imunodeficientes, resulta em doença acentuada ou diarréia que pode ser fatal. O objetivo deste estudo foi avaliar a evolução da infecção experimental pela linhagem MMC, de Cryptosporidium sp de origem humana, nas linhagens de camundongos imunodeficientes C57BL/6 KO para IFN-y, C.B-17/Uni scid,' C57BL/Uni bg, C3H/Uni nu e imunocompetentes BALB/c/Uni e C57BL/6/Uni. Para tanto, a manutenção do cultivo "in vivo" da linhagem MMC de Cryptosporidium sp foi realizada mediante várias passagens em camundongos neonatos imunocompetentes e camundongos adultos KO para IFN-y. Foram utilizadas remeas SPF com 04 a 06 semanas de vida das linhagens imunodeficientes e imunocompetentes, inoculadas com 105 oocistos de Cryptosporidium sp por tubagem esofágica. Para a avaliação da dinâmica da eliminação de oocistos de Cryptosporidium sp, as fezes dos animais foram colhidas diariamente, durante 15 dias e armazenadas em dicromato de potássio 2,5% a 4°C. Para o estudo da patologia intestinal, os animais foram sacrificados no 15° ou 44° dias após a infecção, e retirados segmentos do jejuno, íleo, ceco e colon para posterior avaliação histológica. A análise conjunta da mortalidade dos camundongos infectados pelo Cryptosporidium sp e da eliminação de oocistos indica que o perfil da resistência à infecção nas linhagens em estudo apresentou o seguinte padrão: C57BL/6/Uni> BALB/c/Uni > scid> bg> nude > KO. As alterações histológicas no intestino das linhagens estudadas apresentaram um perfil de severidade das lesões na seguinte ordem: KO > bg> nude > scid> BALB/c/Uni = C57BL/6/Uni. Dentre as linhagens avaliadas, os camundongos KO foram os mais susceptíveis a infecção pelo Cryptosporidium sp, quanto a mortalidade, eliminação de oocistos e alterações histológicas no intestino. A linhagem C57BL/6 KO para IFN-y pode ser considerada o melhor modelo para o estudo da criptosporidiose experimental. Estes resultados também ressaltam a importância do IFN-y no controle da criptosporidiose na fase aguda da infecção, assim como a importância das células NK e linfócitos T no controle da criptosporidiose. A comparação da análise histopatológica do scid, nude e bg sugerem que a resposta humoral tem pequena participação no controle da criptosporidiose
Abstract: Cryptosporidium is a protozoan parasite that can cause chronic life-threatening diarrhea in immunocompromised persons. In immunocompetent hosts, C. parvum causes a self-limiting diarrheal illness that can persist until 3 weeks. Cryptosporidium sp isolated ttom a HIV - positive patient in Campinas (Brazil) has been maintained by repeated oocyst passage through S.P.F. suckling mice. Differences in susceptibility to cryptosporidial infections were investigated among four immunodeticient adult mice strains: C57BL/6 gamma-interferon-knockout (KO), C57BL/6/Uni bg, C3H1Uni nu and C.B-17/Uni scid. The mice were infected via oral inoculation with 105 Cryptosporidium sp MMC oocysts and monitored for infection intensity by collection of fecal pellets ttom individual mice. After 15 or 44 days, the mice were sacriticed in order to evaluate the damage at distaljejunun, ileum, caecum and colono There was differences highly signiticant in the fecal oocyst shedding among KO, bg, scid, nu and adult immunocompetent controls (C57BL/6/Uni and BALB/c/Uni). The resistance pattem conceming the mortality and oocysts shedding among the mice strains, was: C 57BL/6>BALB/c>scid>bg>nude>KO. Histological intestinal evaluation 15 days after infection, showed that KO mice showed pronounced histological changes and scid mice were less infected. The response of the epithelium to cryptosporidial infection after 44 days showed signals of recovery and it was possible to suggest the following panel conceming the recovery capacity : scid>bg>nude>KO. The results of this study demonstrated that there is correlation between resistance pattem and histological alterations. These findings support theview that IFN-y, T and NK cells are very important for the control of infection meanly during the early recovery phase against Cryptosporidium sp infection. The results also suggest that the role of B cells in the resolution of murine infection against Cryptosporidium is minore
Doutorado
Doutor em Parasitologia

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Zhang, Yantong, and Pedro Escribano. "Active Forwarder Cab Suspension." Thesis, KTH, Maskinkonstruktion (Inst.), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-190138.

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The forest industry plays an important role in Sweden, and forest machine manufactures are underconstant pressure to achieve both high productivity and comfortable operating environment in its products. A forwarder is a forestry vehicle that carries logs which are cut by a harvester. It suffers alot of low frequency and high amplitude vibrations during the operation because of the rough terrainin forests. Therefore, it is necessary and vital to introduce an active cab suspension system in orderto reduce the whole vibrations in the forwarder cab.The main purposes of this thesis are to develop, implement and test a feasible control strategy forthe active cab suspension system as well as verify the controller’s performance in terms of vibrationreduction and power consumption. This project is focused on the available mechanical rig installedat KTH lab hall, instead of a real forwarder.A deep study has been carried out on a new valve prototype. Exhausted tests were made to testthe performance of this valve under different conditions. From the test results, the valve was tunedin order to get the best performance out of it. Once the valve has been well calibrated, a model ofthe whole system was estimated by using Black-box estimation. The model has a 96% of matchingbetween the stimulation data and the validation data. Different controllers were designed with thismodel, and the best one was designed by the gain scheduling method.The system has a delay of 36 ms, therefore, it was studied how the performance of this controllerwould increase if this delay was reduced. The study shows that reducing the delay to around 0-2ms, the suspension system is able to reduce the vibration from 60% to 90%. Smith Predictor wasimplemented into the gain scheduling controller in order to reduce the effect of the delay. The resultsdemonstrated a better and more robust performance of the controller with Smith Predictor.Several test cases were implemented to seek a wide range of possible vibrations that a forwardercould handle in the forest. These tests have been done both in a test rig and in a simulationenvironment. The final test was conducted by using a real track test model obtained from Skogforsk.This track is used for testing different systems in a test forwarder since it simulates the terrain ina forest. Based on the simulation result, the total disturbance reduction percentages of SmithPredictor controller are 75% for heave, 68% for pitch and 73% for roll, which shows the systemreduces the cab vibration. Moreover, the maximum amount of power needed during the forwarderoperation is 11.63 kW which is feasible for implementing this system on the actual forwarder.

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Louis, Thibaut. "High resolution CMB physics." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:b0d62439-37b8-4aa8-8d17-70141a70572a.

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This thesis presents the measurement of the cosmic microwave background (CMB) power spectrum for the Atacama Cosmology Telescope (ACT) experiment and its polarized upgrade, ACTPol. I present the tools that I have developed for constructing unbiased and nearly optimal statistical estimators. I discuss how to separate the cosmological and the astrophysical signal and how to characterize instrumental systematics. The goal of this work is to obtain accurate power spectra measurement that can be used for cosmological parameter estimation. I first present the analysis of the complete ACT data set. The high resolution of the telescope allows us to recover power spectra to ℓ = 10000. I report the measurement of the power spectra at 148 GHz and 218 GHz, as well as the cross-frequency spectrum between the two channels. The power spectrum measurement is consistent with the ΛCDM model and a basic foreground model. I then present the cross correlation of maps from the Atacama Cosmology Telescope with maps from the Planck satellite in two overlapping regions covering 592 square degrees. I find excel- lent agreement between the two datasets at both frequencies, quantified using the variance of the residuals between the ACT power spectra and the ACT×Planck cross-spectra. The next generation of CMB experiments are focused on measuring its polarization. I present efficient algorithms for CMB lensing simulation and power spectrum estimation for flat-sky CMB polarization maps. Finally, I discuss the first temperature and polarization power spectra measurement from the ACTPol experiment. They are the first attempt to measure the polarization of the CMB at high resolution.

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Relógio, André Gaspar Tchoia. "Importância do CFB para o desenvolvimento regional: O caso do Huambo." Master's thesis, Universidade Portucalense, 2015. http://hdl.handle.net/11328/1367.

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Dissertação de Mestrado em Gestão.
O trabalho em causa teve como objetivo central debruçar-se sobre a importância do CFB para o desenvolvimento regional, o caso do Huambo. Para a concretização do estudo recorreu-se a um conjunto de métodos dos quais sobressaem, o hipotéticodedutivo, o estudo casual comparativo, os métodos fatual e teórico e lógico-histórico, que permitiram fazer a valoração dos antecedentes patrimoniais do CFB e a sua evolução no decorrer do tempo de 1903 a 2014. Para amostra considerou-se a própria EP do CFB. Este estudo procurou analisar com base nos dados da entrevista, os 47 meses de exploração de 2004 a 2008, os trajetos no CFB da Stª. Iria à Calenga no Huambo num troço de 44 Km e 154 Km para Benguela (Lobito ao Cubal), por sua vez, com base na pesquisa documental fazer o estudo comparativo do funcionamento deste CF desde 1903 a 2014. Os resultados obtidos permitem verificar que o comboio perdeu parte do seu fulgor em Angola devido à guerra, mas com o advento da paz e das ações das autoridades este quadro tende a mudar. Os resultados do estudo permitem concluir que o meio social foi influenciado pelo CFB no do caso do Huambo, e de um modo geral em África, o CF contribuiu para a transformação profunda da geografia económica ao ponto de permitirem desencravar regiões no interior, e assim assegurar mercados para produtos manufaturados vindos das indústrias dos países mais avançados.
The work in aim has as main objective to speak about the importance of CFB for regional development, Huambo in face. For such concreteness we had to follow the several method: hypothetic - deductive, casual comparative, theoric factual and logistical historical that allow us to do valorization CFB patrimonial record and its evolution from 1903 up to 2014. For the representative illustrative the public enterprise called CFB. The study came from an interview took place in 47 month of exploration on year 2004 and 2008 from Santa Iria up to Calenga railway station in total of 44 Km and 154 km to Benguela (passing Lobito - Cubal) and finally comparative analyses of the railway company running from 1903 to 2014. The achieve statement goal let we to verify that train last many brilliant due to civilian war, but with peace and the power of authorities government this situation seems to change. The result of investigation allow us to concluding that social means push CFB, Huambo in case and in Africa in general case, the CF contributes to deeply transformation of economy geography used regional and also assure the market of manufactured product coming from advance country in industry.
Orientação: Prof. Doutor Fernando Oliveira Tavares.

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Billi, Matteo. "Joint temperature and polarisation analyses of the lack of power anomaly in the CMB anisotropy pattern." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16205/.

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La Radiazione Cosmica di Fondo (CMB) è la radiazione emessa nell’Universo primordiale dopo la ricombinazione di elettroni e protoni in idrogeno neutro. Le osservazioni della CMB negli ultimi 30 anni hanno fortemente contribuito alla nascita della cosmologia di precisione, e all’affermazione di un modello cosmologico standard, denonimato ΛCDM, i cui parametri sono stimati con un’incertezza dell’ordine del percento o addirittura inferiore. Ciò nonostante ci sono caratteristiche non ben comprese osservate alle grandi scali angolari della mappa in temperatura di CMB, note come anomalie. Una di queste, la mancanza di potenza rispetto a quanto previsto nel modello ΛCDM, potrebbe indicare l’esistenza di una nuova fase cosmologica antecedente all’epoca inflazionaria. Tale anomalia, osservata in modo consistente sia da WMAP che da Planck, non possiede però la significatività statistica necessaria per affermare l’esistenza di tale nuova fase. Al fine di studiare questa mancanza di potenza abbiamo utilizzato diversi estimatori statistici, che includono nell’analisi sia le mappe in temperatura che quelle in polarizzazione. Estimatori specifici ed innovativi, basati sullo spettro di potenza angolare della CMB, sono stati costruiti, testati e utilizzati su simulazioni e sui dati ottenuti dal satellite Planck nel 2015. Il confronto tra le simulazioni e i dati è stato valutato fornendo la percentuale di consistenza. Sono state inoltre fornite previsioni sulla sensibilità degli estimatori proposti quando impiegati su future osservazioni di CMB. Il miglioramento trovato può arrivare a un fattore dell’ordine 30, dimostrando che le misure future di polarizzazione della CMB potranno aiutare a trasformare una anomalia, attualmente osservata solo in temperatura, in una rilevazione di un nuovo fenomeno fisico.

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Todorovic, Magdolna. "CMB foregrounds at 33 GHz." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498967.

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Lam, Yukyam 1982. "Dark energy and CMB anisotropy." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32743.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2004.
Includes bibliographical references (p. 59-60).
According to the WMAP and earlier COBE observations, the Cosmic Microwave Background (CMB) anisotropy power on large angular scales appears to be significantly lower than predicted by the standard model of cosmology. We propose a scalar field model of the dark energy as a mechanism for suppressing low l multipoles through late-Universe evolution of metric fluctuations and the integrated Sachs-Wolfe (ISW) effect. We find that for a constant dark energy equation of state, theoretical predictions actually give a larger (instead of a desired smaller) value of the quadrupole and other low l multipoles.
by Yukyan Lam.
S.B.

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Rodrigues, Ana Sofia Ribeiro. "Aprendizagem cooperativa no 1º CEB." Master's thesis, Universidade de Aveiro, 2018. http://hdl.handle.net/10773/22947.

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Mestrado em Educação Pré-escolar e Ensino no 1º Ciclo do Ensino Básico
A escola tem o dever de garantir a aprendizagem de conteúdos científicos, mas também a missão de formar os alunos, através do desenvolvimento de atitudes e valores que permitam gerar cidadãos interventivos, capazes de participar de forma plena numa sociedade humana caraterizada por diversidade, liberdade, justiça e equidade, em que o potencial de cada indivíduo é otimizado. Este relatório apresenta o trabalho realizado no contexto da componente de Prática de Ensino Supervisionada, do Mestrado em Educação Pré-Escolar e Ensino do 1º CEB da Universidade de Aveiro, constituída pelas unidades curriculares Prática Pedagógica Supervisionada e Seminário de Orientação Educacional.Foi desenvolvido com um grupo de crianças do 3º ano de escolaridade, e teve como objetivos centrais, compreender e promover processos de aprendizagem colaborativa entre as crianças, com base na relação de colaboração entre os adultos intervenientes, e entre as próprias crianças. Ao longo de todo o trabalho, o bem-estar emocional e a implicação, variáveis processuais desenvolvidas no contexto da Abordagem Experiencial em Educação, permitiram obter contínuo feedback sobre a contingência da intervenção face às necessidades, interesses e motivações que as crianças evidenciavam.
The school has the obligation to ensure learning of scientific syllabus, but also the mission of educating students through the development of attitudes and values that allow the formation of interventional citizens, capable of fully participating in a human society characterized by diversity, freedom, justice and equity, where each individual's potential is optimized. This report presents the work done in the context of the Supervised Teaching Practice component of the Master on Early Childhood and Primary Education, at the University of Aveiro, consisting of the Supervised Pedagogical Practice and Educational Guidance Seminar courses. It was developed with a group of children at third. grade, aiming to understand and promote collaborative learning processes among children, based on the collaborative relationship between the intervening adults, and between the children themselves. Throughout the project, emotional well-being and involvement, process variables developed in the context of the Experiential Approach in Education, allowed to obtain continuous feedback on the contingency of intervention to the needs, interests and motivations that children evidenced

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Bártek, Petr. "Nová koncepce hydraulického pohonu CPB." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230510.

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The main objective of this master's thesis is to design the new conception of hydraulic drive of the baling press CPB 100 with application of modern tendencies in the field of hydraulic engineering. This thesis contains design and calculations of new hydraulic drive, hydraulic circuit diagram and the list of hydraulic elements that are used. Moreover this thesis includes the design of an electrical control and the design of hydraulic block and manifold.

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NATALE, Umberto. "Distilling information from present and future CMB datasets: the cases of large-scale polarization and lensing." Doctoral thesis, Università degli studi di Ferrara, 2021. http://hdl.handle.net/11392/2488201.

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The level of precision expected by future cosmic microwave background experiments makes it necessary to refine the techniques used to analyse the data. It becomes essential to understand how to maximise their information content. This can be done, either by developing techniques to reduce the noise level present in the data or by systematically studying the significance of different observations for a given model. In addition, it is possible to define new estimators to test their statistical properties. In this thesis, we initially show how it is possible to construct a pixel-based dataset that combines the WMAP and low-frequency \Planck\ large-scale polarization maps. After demonstrating its robustness, we derive constraints on the optical depth obtaining $\tau = 0.069^{+ 0.012}_{- 0.011}$ (68\% CL). Adding small-scale data, BAO and lensing we find $\tau = 0.0714 _{- 0.0096}^{+ 0.0087}$ (68\% CL). As a further topic, we show how it is possible to define new estimators to study the correlation between the orientation of the Galactic plane and the low-variance anomaly shown by large angle CMB temperature data. Through the use of random rotations, we show the stability of this anomaly at high Galactic latitudes, finding a significance of $\sim 3 \sigma$. Finally, we compare two main observables in CMB experiments: lensing and large-scale polarization. We show how the information carried by these two probes affects our ability to constrain the base $\Lambda$CDM parameters. We extend the analyses considering also some of its most debated extensions, quantifying which future probe will play a crucial role in their characterisation.
Il livello di precisione atteso dai futuri esperimenti sulla radiazione cosmica di fondo rende necessario il perfezionamento delle tecniche utilizzate per analizzare i dati. Diviene indispensabile capire come massimizzare il loro contenuto informativo. Questo pu\`o essere fatto sia sviluppando tecniche per ridurre del livello di rumore presente nei dati, sia tramite lo studio sistematico della significativit\`a delle diverse osservazioni per un determinato modello. In aggiunta, \`e possibile definire nuovi estimatori per testarne le propriet\`a statistiche. In questo lavoro di tesi, inizialmente mostriamo come sia possibile costruire un dataset nello spazio dei pixel che combini le mappe di polarizzazione su larga scala ottenute dalle misure a bassa frequenza di WMAP e \Planck. Dopo averne dimostrato la robustezza, deriviamo i vincoli sullo spessore ottico ottenendo un valore pari a $\tau=0.069^{+0.012}_{-0.011}$ (68\% CL). Aggiungendo misure derivanti dalle piccole scale, BAO e lensing troviamo un valore pari a $\tau=0.0714_{-0.0096}^{+0.0087}$ (68\% CL). Come ulteriore argomento, facciamo vedere come sia possibile definire nuovi estimatori per studiare la correlazione tra l'orientazione del piano Galattico e l'abbassamento anomalo della varianza visto nei dati di temperatura della CMB su larga scala angolare. Tramite l'uso di rotazioni random mostriamo la stabilit\`a di questa anomalia ad alte latitudini Galattiche, trovando una significativit\`a di $\sim 3 \sigma$. Infine, compariamo due osservabili principali negli esperimenti di CMB: quella del lensing e quella della polarizzazione su larga scala. Mostriamo come l'informazione contenuta in queste due sonde influenzi la nostra capacit\`a di vincolare i parametri base del modello $\Lambda$CDM. Estendiamo l'analisi considerando anche alcune delle sue estensioni pi\`u dibattute, quantificando quale sar\`a la sonda che giocher\`a un ruolo cruciale nella loro caratterizzazione.

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Marinozzi, Maria Chiara. "Characterization of the complement hereditary and acquired abnormalities in atypical Hemolytic Uremic Syndrome and C3 Glomerulopathy." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCB037/document.

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Rodrigues, Tatiana Alves [UNESP]. "Estudo da interação biosortiva entre o corante reativo procion blue MXG e as linhagens CCB 004, CCB 010 e CCB 650 de Pleurotus ostreatus paramorfogênico." Universidade Estadual Paulista (UNESP), 2003. http://hdl.handle.net/11449/95023.

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Made available in DSpace on 2014-06-11T19:27:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-03-31Bitstream added on 2014-06-13T19:35:30Z : No. of bitstreams: 1 rodrigues_ta_me_rcla.pdf: 1337259 bytes, checksum: 4cefa1a7ab0cc7cf4520e68caebc9830 (MD5)
A presente pesquisa enfoca a utilização de formas paramorfogênicas de diferentes linhagens de Pleurotus ostreatus para remover o corante reativo Procion Blue MXG de soluções aquosas. O fungo induzido fisicamente em sua forma paramorfogênica (pellets) foi usado no estudo da biosorção do corante em diferentes valores de pH e em comparação entre as hifas autoclavadas e não autoclavadas, visando a remoção do mesmo em solução aquosa. O corante reativo Procion Blue MXG foi analisado em sua estabilidade espectral em diferentes valores de pH. Este corante se mostrou instável em termos de estabilidade espectral. O pH que melhor se enquadrou quanto à capacidade de remoção das biomassas pelletizadas foi o 2,50, tanto para amostras autoclavadas como não autoclavadas Em praticamente todos os experimentos de interação entre a biomassa e o corante, as autoclavadas apresentaram maior capacidade biosortiva do que as não autoclavadas. Foram também efetuados estudos comparativos a respeito das equações Isotermas de adsorção de Freundlich e Langmuir. A comparação entre os coeficientes de correlação de ambas, nas condições de 30º C e pH 2,50 indicam que a equação de Langmuir explica melhor a interação entre aa biomassa fúngica e o corante estudado em todas as linhagens, quando não autoclavadas, admitindo-se tratar de um processo biosortivo em monocamada. Para as amostras autoclavadas, a equação de Langmuir também é válida para a linhagem CCB 010, sendo que para as linhagens CCB 004 e CCB 650, a equação de Freundlich prevaleceu. Os testes de biosortividade em termos de varredura espectral indicam que as linhagens CCB 010 e CCB 650 apresentam tendência de ter potencial enzimático para degradar o corante, principalmente em pH 2,50. Pelos dados apresentados, podemos afirmar que, do ponto de vista de biosorção, o Pleurotus ostreatus e... , was used in the dye's biosorption study, in different values of pH and in comparasion between alive and dead fungi micelia, aiming at its removal in watery solution. The reactive dye Procion Blue MXG was analyzed in its spectral stability in different values of pH. This dye was showed as unstable in terms of spectral stability. The pH that has better fits in the capacity of removal of biomass was the 2,50, as much for dead samples as for alive samples. In practically all the experiments of interaction between the biomass and the dye, the deceased samples had presented greater biosorptive capacity than the alive ones. Also comparative studies regarding the isothermal equations of adsoption of Freundlich and Langmuir had been effected. The comparison between the coefficients of correlation of both, in the conditions of 30ºC and pH 2,50 indicates that the equation of Langmuir explains better the interaction between the fungic biomass and the dye in all the strains, when deceased, admitting itself to deal with a biosorptive process in monolayer. For the dead samples, the equation of Langmuir also is valid for strain CCB 010, being that for strains CCB 004 and CCB 650, the equation of Freundlich has prevailed. The tests of biosorptivity in terms of spectral sweepings indicate mainly that strains CCB 004, CCB 010 and CCB 650 present trend to have enzymatic potential to degrade the dye, in pH 2,50. For the presented data, we can affirm that, of the point of view of the biosorption., paramorphic Pleurotus ostreatus and its strains offers conditions to come to be used as biosorbent substratum in the treatment of industrial effluent who contains these azo compounds.

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Holl, Hans-Guido [Verfasser], and Helmut R. [Akademischer Betreuer] Salih. "Einfluss von Komplementfaktor C3a und synthetischem C3a-Rezeptor-Agonist auf die C3a-Rezeptorexpression und Antitumorreaktivität von natürlichen Killerzellen / Hans-Guido Holl ; Betreuer: Helmut R. Salih." Tübingen : Universitätsbibliothek Tübingen, 2016. http://d-nb.info/119812167X/34.

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Rodrigues, Tatiana Alves. "Estudo da interação biosortiva entre o corante reativo procion blue MXG e as linhagens CCB 004, CCB 010 e CCB 650 de Pleurotus ostreatus paramorfogênico /." Rio Claro : [s.n.], 2003. http://hdl.handle.net/11449/95023.

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Orientador: Carlos Renato Corso
Banca: Adriana de Mello Gugliotta
Banca: Sandra Mara Martins Franchetti
A presente pesquisa enfoca a utilização de formas paramorfogênicas de diferentes linhagens de Pleurotus ostreatus para remover o corante reativo Procion Blue MXG de soluções aquosas. O fungo induzido fisicamente em sua forma paramorfogênica (pellets) foi usado no estudo da biosorção do corante em diferentes valores de pH e em comparação entre as hifas autoclavadas e não autoclavadas, visando a remoção do mesmo em solução aquosa. O corante reativo Procion Blue MXG foi analisado em sua estabilidade espectral em diferentes valores de pH. Este corante se mostrou instável em termos de estabilidade espectral. O pH que melhor se enquadrou quanto à capacidade de remoção das biomassas pelletizadas foi o 2,50, tanto para amostras autoclavadas como não autoclavadas Em praticamente todos os experimentos de interação entre a biomassa e o corante, as autoclavadas apresentaram maior capacidade biosortiva do que as não autoclavadas. Foram também efetuados estudos comparativos a respeito das equações Isotermas de adsorção de Freundlich e Langmuir. A comparação entre os coeficientes de correlação de ambas, nas condições de 30º C e pH 2,50 indicam que a equação de Langmuir explica melhor a interação entre aa biomassa fúngica e o corante estudado em todas as linhagens, quando não autoclavadas, admitindo-se tratar de um processo biosortivo em monocamada. Para as amostras autoclavadas, a equação de Langmuir também é válida para a linhagem CCB 010, sendo que para as linhagens CCB 004 e CCB 650, a equação de Freundlich prevaleceu. Os testes de biosortividade em termos de varredura espectral indicam que as linhagens CCB 010 e CCB 650 apresentam tendência de ter potencial enzimático para degradar o corante, principalmente em pH 2,50. Pelos dados apresentados, podemos afirmar que, do ponto de vista de biosorção, o Pleurotus ostreatus e... (Resumo completo, clicar acesso eletrônico abaixo).
The present research focuses the use of paramorphic forms of different strains of Pleurotus ostreatus, to remove the reactive dye Procion Blue MXG from aqueous solutions. This fungi induced phisically in its paramorphic form (pellets), was used in the dye's biosorption study, in different values of pH and in comparasion between alive and dead fungi micelia, aiming at its removal in watery solution. The reactive dye Procion Blue MXG was analyzed in its spectral stability in different values of pH. This dye was showed as unstable in terms of spectral stability. The pH that has better fits in the capacity of removal of biomass was the 2,50, as much for dead samples as for alive samples. In practically all the experiments of interaction between the biomass and the dye, the deceased samples had presented greater biosorptive capacity than the alive ones. Also comparative studies regarding the isothermal equations of adsoption of Freundlich and Langmuir had been effected. The comparison between the coefficients of correlation of both, in the conditions of 30ºC and pH 2,50 indicates that the equation of Langmuir explains better the interaction between the fungic biomass and the dye in all the strains, when deceased, admitting itself to deal with a biosorptive process in monolayer. For the dead samples, the equation of Langmuir also is valid for strain CCB 010, being that for strains CCB 004 and CCB 650, the equation of Freundlich has prevailed. The tests of biosorptivity in terms of spectral sweepings indicate mainly that strains CCB 004, CCB 010 and CCB 650 present trend to have enzymatic potential to degrade the dye, in pH 2,50. For the presented data, we can affirm that, of the point of view of the biosorption., paramorphic Pleurotus ostreatus and its strains offers conditions to come to be used as biosorbent substratum in the treatment of industrial effluent who contains these azo compounds.
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