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

Molecular Analysis of Human T-cell Leukemia Virus Type 2 Accessory Protein p28

Yamamoto, Brenda Michiyo 26 June 2009 (has links)
No description available.
2

Hydraulic model study of a manhole junction

Parker, David G. January 1967 (has links)
The object of this investigation was the experimental investigation of the hydraulics of a flow-through manhole with one lateral connection. An attempt was made to use the conservation of momentum principle to develop a mathematical relationship which satisfied the data obtained in the model study. Three forms of the momentum equation were developed by statistical evaluation of loss coefficients. The best of the three equations was chosen on the basis of its ability to predict flow depths and its consistency with hydraulic concepts. A procedure was then developed for using this equation to obtain a value of the required outlet pipe invert 'drop for a given set of flow conditions. The use of the procedure was illustrated by the solution of an example problem·of a system of three pipes. / Master of Science
3

p28 DYNEIN LIGHT CHAINS AND CILIARY MOTILITY IN Tetrahymena thermophila

Subramanian, Aswati 17 January 2014 (has links)
No description available.
4

Modulation zellulärer Signalwege und antiviraler Mechanismen in Makrophagen durch Orthopockenviren

Bourquain, Daniel 13 May 2013 (has links)
Nach der Eradikation der humanen Pockenerkrankung stellen zoonotische Orthopockenvirus-(OPV-)Infektionen heute eine mögliche Bedrohung der öffentlichen Gesundheit dar. Hierbei sind insbesondere Kuhpocken-(CPXV), Affenpocken-(MPXV) und Vaccinia Viren (VACV) von Bedeutung. In dieser Arbeit wurde das Genexpressionsprofil humaner (HeLa) Zellen nach Infektion mit CPXV, MPXV oder VACV untersucht. Es wurden sowohl zelluläre Gene identifiziert, welche generell von allen verwendeten Viren reguliert wurden, als auch Gene, die eine Virus-spezifische Regulation durch individuelle OPV aufwiesen. Gemeinsamkeiten zeigten sich insbesondere zwischen CPXV und MPXV, welche, im Gegensatz zu VACV, die Expression zahlreicher Cytokine und Chemokine induzierten. Insbesondere für Interleukin-6, -8 und CXCL1 konnte auch auf Proteinebene eine gesteigerte Sekretion durch CPXV-infizierte Zellen nachgewiesen werden. Vermutlich aufgrund dieser Induktion, trat in vitro eine verstärkte Rekrutierung von Monozyten und Makrophagen in Folge einer CPXV-, nicht aber einer VACV-Infektion auf. Makrophagen spielen eine kontroverse Rolle im Rahmen einer OPV-Infektion und sind sowohl für deren Bekämpfung, als auch, im infizierten Zustand, für die Ausbreitung der Viren im Organismus von Bedeutung. Daher wurde die Replikationsfähigkeit von CPXV und VACV in Makrophagen charakterisiert. Der Virulenzfaktor p28, welcher von den meisten VACV Stämmen nicht kodiert wird, konnte als essentiell für die Replikation von CPXV in einer murinen Makrophagen-Zelllinie, primären peritonealen Makrophagen der Ratte und in Makrophagen aus primären humanen PBMCs identifiziert werden. In Anbetracht der Bedeutung der Replikationsfähigkeit in Makrophagen für die Ausbreitung einer OPV-Infektion im Wirtsorganismus, deuten diese Ergebnisse darauf hin, dass CPXV, im Fall einer weiteren Adaption an den Menschen, ein höheres Bedrohungspotential im Vergleich zu VACV aufweisen könnten. / Today, following the eradication of human smallpox, zoonotic infections caused by orthopoxviruses (OPV) are emerging as a potential human health threat. Especially cowpox viruses (CPXV), vaccinia viruses (VACV), and monkeypox viruses (MPXV) are gaining importance as a cause of infectious disease of man and livestock. This study aimed to analyse and compare the gene expression profile of human (HeLa) cells following infection with CPXV, MPXV or VACV. Cellular genes were identified which were either commonly modulated by infection with any of the three viruses, or which were specifically modulated by one individual OPV. Particularly similar effects on cellular gene expression were observed in the case of CPXV and MPXV infection, which both induced the expression of several cytokine and chemokine genes. Especially interleukin-6, -8, and CXCL1 were strongly secreted by CPXV-infected cells but not by VACV-infected cells. Consequently, CPXV infection also induced a strong chemotactic recruitment of monocytes and macrophages in vitro in contrast to VACV infection. Especially macrophages are known to play a controversial role during OPV infection. On the one hand, macrophages are of importance for the control of the infection. On the other hand, infected macrophages also facilitate virus spread across the organism. Therefore, the capability of CPXV and VACV to replicate in macrophages was analysed. Thereby, the poxviral virulence factor p28, which is absent from most strains of VACV, was identified as an essential factor, allowing CPXV replication in a murine macrophage cell line, primary peritoneal rat macrophages and in human PBMC-derived macrophages. Concerning the importance of productively infected macrophages for OPV spread, these results suggest that CPXV, if further adapted to human beings as host species, may harbor a greater threat to human health when compared to VACV.
5

CHARACTERIZATION OF THE HUMAN T-CELL LEUKEMIA VIRUS TYPE-2 P28 ACCESSORY PROTEIN

Doueiri, Rami 27 August 2012 (has links)
No description available.
6

Structural prediction analysis of ehrlichia chaffeensis outer membrane proteins, p28 Omp-14 and p28 Omp-19 assessed by circular dichrosim and porin assays

Thotakura, Gangadaar January 1900 (has links)
Master of Science / Department of Diagnostic Medicine/Pathobiology / Roman Reddy R. Ganta / Ehrlichia chaffeensis, a Gram-negative organism belonging to the order Rickettsiales, is responsible for an emerging infectious disease in humans, the human monocytic ehrlichiosis. E. chaffeensis also infects several other vertebrate hosts including dogs, goats, coyotes and white tailed deers. This organism is transmitted by an infected tick, Amblyomma americanum. The exact pathogenic mechanisms involved for the persistence of the pathogen in vertebrate hosts are still unclear. E. chaffeensis protein expression varies significantly in vertebrate and tick hosts. Differentially expressed proteins include the immunodominant outer membrane proteins encoded by the p28-Omp multigene locus. The p28-Omp 14 is expressed primarily in tick cells and the p28-Omp 19 is the major expressed protein in macrophages both under in vitro and in vivo conditions. The objective of this study is to prepare recombinant proteins and use them to assess the secondary structures and protein functions. The protein sequences were analyzed with the aid of bioinformatics programs to make structural predictions. The analysis suggested the presence of eight β barrel structures for both the p28-Omp proteins. The coding sequence of the p28-Omp genes were cloned and over expressions of proteins in in E. coli was accomplished by using the plasmid expression construct, pET28. The proteins were purified to near homogeneity and used to refold using detergents to mimic native protein structure in the bacterial outer membrane. Refolding of proteins was analyzed by two methods; SDS-PAGE and Circular Dichroism. The Circular dichroism spectroscopy analysis suggested the formation of β-sheet structures of proteins in micelles formed with the detergents. β-sheet structures may have been formed with the hydrophobic domains of the protein imbedded in the micelles. The hydrophilic segments (predicted by bio informatics analysis) may be exposed to the aqueous phase. The recombinant proteins were also iii used to prepare proteoliposomes and tested for the porin activity. The analysis demonstrated the porin activity for both p28-Omp 14 and 19 recombinant proteins by using mono-, di- and tetra- saccharides as well as for amino acid L-glutamine. This study forms the basis for initiating studies to compare the structural difference between the two differentially expressed proteins of E. chaffeensis.
7

Identification and Characterization of the Expression Profile of Oligodendrocyte-Derived and Associated Proteins via Unilateral X-Irradation of the Rat Optic Nerve

Greco, Nicholas 01 January 2005 (has links)
Recent studies examining cell-cell interactions during CNS development and following disease or trauma have highlighted our limited understanding of the in vivo functions of the myelinating cell of the CNS, the oligodendrocyte. With this in mind, our laboratory has developed techniques by which a profile of proteins derived from or regulated by oligodendrocytes can be elucidated. Specifically, we have demonstrated that oligodendrocytes can be selectively eliminated from one optic nerve of a rat by treating the animal with a unilateral exposure of X-irradiation at the time of birth. Consequently, this approach allowed us to experimentally create, within the same animal, one optic nerve devoid of oligodendrocytes and their progenitors (the X- irradiated side) and one optic nerve containing the normal oligodendrocyte population (the untreated side). Using this experimental animal model we hypothesized that uncharacterized proteins, derived from and regulated by oligodendrocytes, which are crucial for CNS development can be identified. Specifically, by comparing protein profiles found within the normal myelinating optic nerve versus the X-irradiated optic nerve, where oligodendrocytes are absent, potential oligodendrocyte-derived proteins can be quickly identified. Further verification that these proteins are indeed related to oligodendrocytes and/or the processes of myelination can be obtained by their reappearance in the 2-D gel protein profile of P28 X-irradiated nerves that, as we have shown previously, undergo a delayed myelination. We then employed mass spectrometric analysis to determine the identities of oligodendrocyte derivedregulated proteins. In this thesis, I will begin by describing our current knowledge of the proteins expressed by oligodendrocytes and their role(s) in oligodendrocyte function. This will be followed by a detailed description of the experimental model system we utilized in an attempt to elucidate the complete repertoire of oligodendrocyte-regulated proteins. We will then describe the results generated fiom our methodology and discuss the implications of our findings in relation to the functional cooperation between oligodendrocytes and other cells of the developing central nervous system. The results generated fiom this project should lead to a clearer understanding of the role of oligodendrocytes and'of the array of proteins whose expression patterns are associated with these cells during CNS development.
8

François Villon in English : translation and cross-cultural poetic influence

Pascolini-Campbell, Claire January 2014 (has links)
This thesis argues that François Villon becomes a significant, but overlooked, influence in the tradition of English poetry, and that this influence reveals itself in translations, adaptations, and responses to his work. By focusing on the way in which numerous high profile poets in the United Kingdom and the United States have reacted to Villon, this study will posit that the reasons behind the appeal of his oeuvre as a source text lie both in the protean nature of his narrative voice and in the myth of his life. The inter-lingual intertextual relationships established through translation and the residue of Villon in English poetic tradition will be presented by means of five case studies, all taking the work of a specific poet as their theme: Algernon Charles Swinburne; Dante Gabriel Rossetti; Ezra Pound; Basil Bunting; and Robert Lowell. These five poets are presented as being exemplary of a greater tradition of translating Villon into English, and will take the reader from the first verse translations of his work in the nineteenth century, to postmodern adaptations and parodies of Villon in the twentieth. They will illustrate the specified intertextual relationships that exist both between source text and target text, and the work of one translator and another, thereby demonstrating the accumulation of influences at play in any one translation of this medieval French poet. In so doing, this thesis will also explore translation and adaptation as dialogical and transformative spaces, distinct from other genres in their ability to establish cross-cultural and interlingual intertexts. Translation and adaptation as spaces of cultural and linguistic hybridity will be demonstrated by observing some of the ways in which Villon has left his mark on English verse, and some of the Villons that anglophone poets have created in their turn.
9

Caractérisation du motif acidique de la sous-unité p28 de l’IL-27 et étude des propriétés partagées entre cette protéine, le CNTF, CLC/CLF et l’interleukine-6

Tormo, Aurélie 06 1900 (has links)
L’interleukine 6 (IL-6) est une cytokine qui joue un rôle essentiel dans l’inflammation. Son récepteur (IL-6R) est composé de la chaîne non signalétique IL-6Rα et de la chaîne transductrice du signal gp130, commune aux cytokines de la famille IL-6. La liaison de l’IL-6 à son récepteur permet l’activation de plusieurs voies de signalisation, notamment des voies Jak/STAT1 et préférentiellement Jak/STAT3. De façon complémentaire, nous avons démontré que l’IL-6 est capable d’activer la voie Jak/STAT5 dans les lymphocytes T CD4. L’activation de cette voie de signalisation pourrait être impliquée dans le rétrocontrôle des effets pro-inflammatoires de l’IL-6 sur les cellules T CD4. Le facteur neurotrophique ciliaire (CNTF) et la « cardiotrophin-like cytokine/cytokine-like factor 1 » (CLC/CLF) sont deux cytokines de la famille de l’IL-6 qui signalent à travers un récepteur commun, le récepteur au CNTF (CNTFR), composé du CNTFRα, « leukaemia inhibitory factor receptor β » (LIFRβ) et gp130. Toutes deux exercent des actions au niveau du système immunitaire, or la chaîne CNTFRα de leur récepteur n’y est pas exprimée. Il a été montré que le CNTFR humain peut également activer un récepteur formé des sous-unités IL-6Rα, LIFRβ et gp130. Nous avons comparé les effets du CNTF et du CLC/CLF de souris sur des transfectants exprimant LIFRβ et gp130 et les chaines α connues de la famille IL-6 (IL-6Rα, IL-11Rβ et CNTFRα). Nos résultats indiquent que le CNTF de souris, comme le CNTF humain est capable d’activer un récepteur formé de l’IL-6Rα, LIFRβ et gp130. Toutefois cette propriété n’est pas partagée par CLC/CLF et le récepteur impliqué dans les effets de cette cytokine sur le système immunitaire reste donc à identifier. L’IL-27 appartient à la famille de l’IL-6 composée d’une sous-unité cytokinique, p28, associée à un récepteur soluble « l’Epstein-Barr virus-induced gene 3» (EBI3). La sous-unité p28 peut s’associer avec le récepteur soluble CLF pour former une cytokine capable d’activer les lymphocytes T. Dans le but de caractériser cette cytokine, nous avons montré que p28/CLF agit aussi sur les lymphocytes B et permet leur différenciation en plasmocytes. Le partage de l’IL-6R par l’IL-6 et p28/CLF semble être à l’origine de la similarité des effets de ces deux cytokines. De plus, nous avons observé des effets semblables à ceux de l’IL-6 suite à l’association de la sous-unité p28 seule avec la chaîne IL-6Rα. En effet, afin de mieux caractériser la cytokine p28/CLF, nous avons étudié les effets dus au recrutement de la chaîne IL-6Rα par la sous-unité p28. Les cytokines de la famille de l’IL-6 sont composées de quatre hélices α disposées de façon anti-parallèle deux à deux. La sous-unité p28 possède, au niveau d’une boucle reliant deux hélices α, un motif de plusieurs acides glutamiques consécutifs (motif polyE) qui n’est retrouvé dans aucune autre cytokine de cette famille. Nous avons démontré que ce motif est impliqué dans la liaison de cette sous-unité avec l’hydroxyapatite et l’os. Cette caractéristique de p28 pourrait permettre un ciblage de l’IL-27 (p28/EBI3) et de p28/CLF préférentiellement vers la niche endostéale des cellules souches et des cellules immunitaires. / Interleukin 6 (IL-6) is a well known cytokine, characterized for its essential function in inflammation. IL-6 receptor (IL-6R) is composed of IL-6Rα, an unsignalling chain, associated with the signaling transducing chain gp130. This glycoprotein is shared by all IL-6 family cytokines. After binding with its receptor, IL-6 preferentially induces the activation of the Jak/STAT3 pathway but can also activate the Jak/STAT1 pathway. Unexpectedly we demonstrated that IL-6 can activate the Jak/STAT5 pathway in CD4 T cells. This STAT5 could act as negative feedback mechanism in response to the pro-inflammatory effects induced by an excess of IL-6. Ciliary neurotrophic factor (CNTF) and cardiotrophin-like cytokine (CLC/CLF) both belong to the IL-6 cytokine family and share the same receptor, the CNTF receptor (CNTFR). CNTFR is composed of CNTFRα, leukaemia inhibitory factor receptor β (LIFRβ) and the glycoprotein gp130. Interestingly, the CNTFRα chain is not expressed by immune cells even though CNTF and CLC/CLF are active on these cells. These effects can be due to the formation of a complex between cytokine and CNTFRα, which can be shedded. This complex can then activate cells expressing only gp130 and LIFRβ. In human, it has been demonstrated that the CNTFRα chain can be substitute with IL-6Rα. Here, we compare mouse CNTF- and CLC/CLF-induced effects in transfected cells expressing LIFRβ, gp130 and different α chains belonging to the IL-6 family (IL-6Rα, IL-11Rα or CNTFRα). Our data demonstrate that like human CNTF, mouse CNTF is able to activate a receptor comprising of IL-6Rα, gp130 and LIFRβ. However, this property is not shared with CLC/CLF. Therefore, second receptor for this cytokine within the immune system still remains to be identify. Interleukin 27 (IL-27) belongs to the IL-6 cytokine family and is composed of the cytokine subunit p28 associated with a soluble receptor chain Epstein-Barr virus-induced gene 3 (EBI3). We demonstrate that the p28 subunit can bind the soluble receptor CLF to form a new dimeric cytokine named p28/CLF. This cytokine is active on T cells and our study demonstrates its activity on B cells. Our results show that p28/CLF sustains plasma cell differentiation. Those IL-6-like properties can be explained by the use of a common receptor, IL-6R. Moreover, our findings demonstrate that p28 has IL-6-like properties when associated with IL-6Rα. In order to better characterize p28/CLF, we next studied effects of to the recruitment of the IL-6Rα chain by p28 subunit. Cytokines belonging to the IL-6 family share a structural particularity by forming a four helix bundle cytokines family. The p28 subunit uniquely expresses a motif composed of a dozen of glutamic acids (polyE motif). We demonstrate that this motif permits p28 binding to hydroxyapatite and bone matrix. This observation could allow a preferential targeting to bone of IL-27 (p28/EBI3) and p28/CLF, and specifically a targeting of stem or immune cells to endosteal niches.
10

Caractérisation du motif acidique de la sous-unité p28 de l’IL-27 et étude des propriétés partagées entre cette protéine, le CNTF, CLC/CLF et l’interleukine-6

Tormo, Aurélie 06 1900 (has links)
L’interleukine 6 (IL-6) est une cytokine qui joue un rôle essentiel dans l’inflammation. Son récepteur (IL-6R) est composé de la chaîne non signalétique IL-6Rα et de la chaîne transductrice du signal gp130, commune aux cytokines de la famille IL-6. La liaison de l’IL-6 à son récepteur permet l’activation de plusieurs voies de signalisation, notamment des voies Jak/STAT1 et préférentiellement Jak/STAT3. De façon complémentaire, nous avons démontré que l’IL-6 est capable d’activer la voie Jak/STAT5 dans les lymphocytes T CD4. L’activation de cette voie de signalisation pourrait être impliquée dans le rétrocontrôle des effets pro-inflammatoires de l’IL-6 sur les cellules T CD4. Le facteur neurotrophique ciliaire (CNTF) et la « cardiotrophin-like cytokine/cytokine-like factor 1 » (CLC/CLF) sont deux cytokines de la famille de l’IL-6 qui signalent à travers un récepteur commun, le récepteur au CNTF (CNTFR), composé du CNTFRα, « leukaemia inhibitory factor receptor β » (LIFRβ) et gp130. Toutes deux exercent des actions au niveau du système immunitaire, or la chaîne CNTFRα de leur récepteur n’y est pas exprimée. Il a été montré que le CNTFR humain peut également activer un récepteur formé des sous-unités IL-6Rα, LIFRβ et gp130. Nous avons comparé les effets du CNTF et du CLC/CLF de souris sur des transfectants exprimant LIFRβ et gp130 et les chaines α connues de la famille IL-6 (IL-6Rα, IL-11Rβ et CNTFRα). Nos résultats indiquent que le CNTF de souris, comme le CNTF humain est capable d’activer un récepteur formé de l’IL-6Rα, LIFRβ et gp130. Toutefois cette propriété n’est pas partagée par CLC/CLF et le récepteur impliqué dans les effets de cette cytokine sur le système immunitaire reste donc à identifier. L’IL-27 appartient à la famille de l’IL-6 composée d’une sous-unité cytokinique, p28, associée à un récepteur soluble « l’Epstein-Barr virus-induced gene 3» (EBI3). La sous-unité p28 peut s’associer avec le récepteur soluble CLF pour former une cytokine capable d’activer les lymphocytes T. Dans le but de caractériser cette cytokine, nous avons montré que p28/CLF agit aussi sur les lymphocytes B et permet leur différenciation en plasmocytes. Le partage de l’IL-6R par l’IL-6 et p28/CLF semble être à l’origine de la similarité des effets de ces deux cytokines. De plus, nous avons observé des effets semblables à ceux de l’IL-6 suite à l’association de la sous-unité p28 seule avec la chaîne IL-6Rα. En effet, afin de mieux caractériser la cytokine p28/CLF, nous avons étudié les effets dus au recrutement de la chaîne IL-6Rα par la sous-unité p28. Les cytokines de la famille de l’IL-6 sont composées de quatre hélices α disposées de façon anti-parallèle deux à deux. La sous-unité p28 possède, au niveau d’une boucle reliant deux hélices α, un motif de plusieurs acides glutamiques consécutifs (motif polyE) qui n’est retrouvé dans aucune autre cytokine de cette famille. Nous avons démontré que ce motif est impliqué dans la liaison de cette sous-unité avec l’hydroxyapatite et l’os. Cette caractéristique de p28 pourrait permettre un ciblage de l’IL-27 (p28/EBI3) et de p28/CLF préférentiellement vers la niche endostéale des cellules souches et des cellules immunitaires. / Interleukin 6 (IL-6) is a well known cytokine, characterized for its essential function in inflammation. IL-6 receptor (IL-6R) is composed of IL-6Rα, an unsignalling chain, associated with the signaling transducing chain gp130. This glycoprotein is shared by all IL-6 family cytokines. After binding with its receptor, IL-6 preferentially induces the activation of the Jak/STAT3 pathway but can also activate the Jak/STAT1 pathway. Unexpectedly we demonstrated that IL-6 can activate the Jak/STAT5 pathway in CD4 T cells. This STAT5 could act as negative feedback mechanism in response to the pro-inflammatory effects induced by an excess of IL-6. Ciliary neurotrophic factor (CNTF) and cardiotrophin-like cytokine (CLC/CLF) both belong to the IL-6 cytokine family and share the same receptor, the CNTF receptor (CNTFR). CNTFR is composed of CNTFRα, leukaemia inhibitory factor receptor β (LIFRβ) and the glycoprotein gp130. Interestingly, the CNTFRα chain is not expressed by immune cells even though CNTF and CLC/CLF are active on these cells. These effects can be due to the formation of a complex between cytokine and CNTFRα, which can be shedded. This complex can then activate cells expressing only gp130 and LIFRβ. In human, it has been demonstrated that the CNTFRα chain can be substitute with IL-6Rα. Here, we compare mouse CNTF- and CLC/CLF-induced effects in transfected cells expressing LIFRβ, gp130 and different α chains belonging to the IL-6 family (IL-6Rα, IL-11Rα or CNTFRα). Our data demonstrate that like human CNTF, mouse CNTF is able to activate a receptor comprising of IL-6Rα, gp130 and LIFRβ. However, this property is not shared with CLC/CLF. Therefore, second receptor for this cytokine within the immune system still remains to be identify. Interleukin 27 (IL-27) belongs to the IL-6 cytokine family and is composed of the cytokine subunit p28 associated with a soluble receptor chain Epstein-Barr virus-induced gene 3 (EBI3). We demonstrate that the p28 subunit can bind the soluble receptor CLF to form a new dimeric cytokine named p28/CLF. This cytokine is active on T cells and our study demonstrates its activity on B cells. Our results show that p28/CLF sustains plasma cell differentiation. Those IL-6-like properties can be explained by the use of a common receptor, IL-6R. Moreover, our findings demonstrate that p28 has IL-6-like properties when associated with IL-6Rα. In order to better characterize p28/CLF, we next studied effects of to the recruitment of the IL-6Rα chain by p28 subunit. Cytokines belonging to the IL-6 family share a structural particularity by forming a four helix bundle cytokines family. The p28 subunit uniquely expresses a motif composed of a dozen of glutamic acids (polyE motif). We demonstrate that this motif permits p28 binding to hydroxyapatite and bone matrix. This observation could allow a preferential targeting to bone of IL-27 (p28/EBI3) and p28/CLF, and specifically a targeting of stem or immune cells to endosteal niches.

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