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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.
51

Applying Mesenchymal Stromal Cells and Platelet-Rich Plasma on a Collagen Matrix to Improve Fascial Repair

Perko, John C. 12 July 2012 (has links)
No description available.
52

Anticancer roles of platelets and aspirin tested on A549 cells

Shang, Lijun, Zhang, Z., Chen, F. 08 1900 (has links)
No / Aspirin, formally known as acetylsalicylic (ASA), is most widely used and cheapest over-the counter drugs. It is used not only for the common fevers, headaches and inflammation, but also for reducing the risk of heart attacks. In recent years, it is also linked to anti-cancer potential. Recently the US Preventive Services Working Group (UPSTF) release aspirin as a guide for cardiovascular disease and primary prevention of colorectal cancer. Platelets have been shown to play a crucial role in cancer metastasis for many years and are proposed to have an intimate reciprocal crosstalk with cancer cells. They may alter the properties of each other and have reciprocal effects. But the exact role of platelets in modifying the tumor cell properties has not been established. In clinical, cancer patients may receive platelets from outside to treat thrombocytopenia and bleeding induced by intensive chemotherapy. Therefore understanding the exact role of platelets in carcinogenesis always is a research interest, especially when evaluating anti-cancer drugs. In this study we exam the effect of platelets on viability, proliferation and adhesion of lung cancer cells A549 in culture conditions, using different concentrations of platelet rich plasma (PRP) with and without the presence of antiplatelet drug aspirin. The tumor cell EMT transformation was also investigated under different combination of PRP and aspirin in vitro. Our data showed that low-dose of aspirin can promote cell proliferation and high-dose of aspirin could inhibit cell proliferation. High concentrations of platelet-rich plasma can inhibit cell proliferation but low concentrations of platelet-rich plasma had no significant effect on cell proliferation. Platelet-rich plasma can gather around the cell to form a gelatinous film, and this lead us to a promoted tumor cell distant metastasis model. We further found out that the combination of aspirin and PRP could increase cell viability compared to single use of PRP and Aspirin can affect cell proliferation by inhibiting platelet effects. Platelet-rich plasma reduces the adhesion of A549 cell can be attenuated by aspirin. Further works will focus on combination of different doses of aspirin and PRP to confirm the above results. Other format of aspirin (nano-form) and other NSAID inflammatory drugs like Ibuprofen will also be tested. / Abstract of conference paper.
53

Compréhension du métabolisme cellulaire et de la synthèse du polyoside capsulaire chez Haemophilus influenzae de type b / Understanding the cell metabolism and synthesis of the capsular polysaccharide from Haemophilus influenzae type b

Le hir, Jerome 25 October 2012 (has links)
Réalisé au sein du LISBP (Laboratoire d’Ingénierie des Systèmes Biologiques et des Procédés, INSA Toulouse), ce travail porte sur l’étude du germe pathogène Haemophilus influenzae de type b (Hib). L’objectif du travail est l’amélioration de la compréhension du métabolisme cellulaire et de la synthèse du polyoside capsulaire chez Hib, utilisé pour la fabrication du vaccin. Ainsi, une étude bibliographique associée à une analyse in silico et à une démarche expérimentale rationnelle a permis de développer un milieu chimiquement défini répondant aux critères de robustesse du procédé et de qualité du produit. Par ce travail, il a pu être défini les facteurs nutritionnels et environnementaux influents sur la production de biomasse et de PRP. Plus généralement, ce travail a permis une meilleure compréhension de la physiologie cellulaire. Une étude Bioinformatique et Transcriptomique a permis l’établissement de cartes métaboliques spécifiques de la souche Hib de notre étude, et de mieux comprendre l’influence du milieu de culture sur la production de polyoside capsulaire. En complément, une étude Fluxomique a permis de développer les connaissances sur le métabolisme général de la souche et plus particulièrement sur la voie de synthèse du polyoside.Sur un plan plus appliqué, une corrélation directe entre la consommation de glucose et la production de polyoside a pu être établie, et ce, dans un environnement maîtrisé de culture en fermenteur. La combinaison du travail développé tant sur le procédé que sur le milieu de culture chimiquement défini ou la sélection de souche, a permis, à l’échelle laboratoire, une multiplication par 6,2 de la production de polyoside capsulaire (7,8 en spécifique) par rapport à la condition initiale de l’étude en milieu complexe. Ce résultat a alors pu être validé chez Sanofi-pasteur à l’échelle pré-industrielle (1000L), tout en conservant une qualité du produit conforme aux critères de production pharmaceutique / This work, undertaken at LISBP (Laboratoire d’Ingénierie des Systèmes Biologiques et des Procédés, INSA Toulouse), concerns the study of the pathogen Haemophilus influenzae type b (Hib). The objective was to improve the understanding of cellular metabolism and the synthesis of the capsular polysaccharide in Hib, used for vaccine production. A literature review coupled with a rational experimental approach has enabled a chemically defined medium that meets the criteria of process robustness and product quality to be developed. This work has defined the key nutritional and environmental factors affecting biomass and PRP production. Bioinformatics and Transcriptomic studies have allowed the specific metabolic characteristics of the Hib strain to be mapped and enabled a better understanding of the influence of culture medium on capsular polysaccharide production to be obtained. A Fluxomics study points to specific organization of the central pathways and more specifically the interaction between the pentose phosphate pathway and the pathway of polysaccharide biosynthesis. On a more applied aspect, direct correlation between glucose consumption and production of polysaccharide was established in a batch culture. The combined knowledge obtained in this study enabled a 6.2-fold increase in production of capsular polysaccharide (7.8 in specific production) to be obtained in laboratory scale installations as compared to the initial fermentation process using complex media. This result was then validated at Sanofi-pasteur at the pilot-plant level (1000L), and shown to maintain product quality as defined by pharmaceutical production criteria
54

Importance of dimerization in aggregation and neurotoxicity of Prion and [alpha]-Synuclein in prion and Parkinson's diseases

Roostaee, Alireza January 2012 (has links)
Abstract: Neurodegenerative diseases are associated with progressive loss of structure or function of neurons which results in cell death. Recent evidence indicate that all neurodegenerative disorders, sporadic or transmissible, may have a common pathological mechanism at the molecular level. This common feature consists of protein aggregation and accumulation of harmful aggregates in neuronal cells resulting in cellular apoptosis and neurotoxicity. Neurodegenerative diseases can affect abstract thinking, skilled movements, emotional feelings, cognition, memory and other abilities. This diverse group of diseases includes Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), prion diseases or transmissible spongiform encephalopathies (TSEs) and amyotrophic lateral sclerosis. In my project I worked on the molecular mechanism of protein aggregation, propagation and neurotoxicity in Parkinson's disease and prion disease. Prion disease and PD are associated with misfolding and aggregation of PrPc and a-Synuclein (a-Syn), respectively. Despite being two important neurodegenerative disorders, molecular mechanisms of a-Syn or PrPC aggregation and amyloidogenesis are still unclear in PD and prion disease. Furthermore, the toxic protein species in PD have not been characterized yet. In this study we characterize the mechanism of a-Syn and PrPc misfolding in a physiological-like cell free condition in the absence of a-Syn aggregates, PrPc ggregated isoform (Pre's), denaturants or acidic environment. A number of studies indicate that dimerization of PrPc or a-Syn may be a key step in the aggregation process. To test this hypothesis we verified if enforced dimerization of PrPc or a-Syn may induce a conformational change reminiscent of the conversion of PrPc or a-Syn to PrPR' or a-Syn aggregates, respectively. We used a well-described inducible dimerization strategy where a dimerizing domain called FK506-binding protein (Fv) was fused to PrPc or a-Syn in order to produce chimeric proteins Fv-PrP and a-SynF'''. A divalent ligand AP20187 was used to induce protein dimerization. Addition of AP20187 to recombinant Fv-PrP in physiological-like conditions resulted in a rapid conformational change characterized by an increase in beta-sheet (13-Sheet) structure and simultaneous aggregation of the proteins. However, non-dimerized PrP formed 13-Sheet conformation in very slower rates. In the presence of AP20187, we also report a rapid random coil into 13-sheet conformational transformation of a-SynF" within 24 h, whereas wild type a-Syn showed 24 h delay to achieve P-sheet structure after 48 h. Electron microscopy experiments demonstrated that dimerization induced amyloid fibril formation after 48 h for both Fv-PrP and a-Syr?", whereas in the absence of dimerizing ligand AP20187, PrP or a-Syn converted into amyloid fibrils after 3 days or even later. Dimerization-induced Fv-PrP aggregates were partially resistant to PK digestion which is a characteristics of the naturally occurring PrPR'. The rates of amyloidogenesis in the presence of dimerization was also characterized by Thioflavin T (ThT) fluorescence probing. Whereas the stable structure of Fv-PrP showed no ThT binding for over 60 h of incubation at 37°C, the addition of AP20187 to Fv-PrP resulted in a time-dependent increase in ThT binding. As for a-SynR, dimerization accelerated the rate of ThT binding and amyloid formation comparing to the slower amyloidogenesis rate of wild type a-Syn in the absence of dimerizer AP20187. The impact of dimerization on a-Syn aggregation was further determined by Fluorescence ANS probing, indicating a higher affinity of dimerization-induced a-SynF" aggregates for binding to ANS comparing to wild type a-Syn aggregates. These results indicate that dimerization increases the aggregation and amyloidogenesis processes for Fv-PrP and a-SynF". Both Fv-PrP and a-SynF" amyloids were successfully propagated in vitro by protein misfolding amplification (PMCA) cycle. These results ar in agreement with the theory that all protein aggregates in neurodegenerative diseases propagate with the same molecular mechanism. Neurotoxicity of recombinant Fv-PrP and a-SynF" aggregates was determined in cellulo and in vivo, respectively. Aggregates of Fv-PrP were toxic to cultured cells whilst soluble Fv-PrP and amyloid fibres were harmless to the cells. When injected to the mice brain, both a-Syni" and a-Syn pre-fibrillar aggregates internalized cells and induced neurotoxicity in the hippocampus of wild-type mice. These recombinant toxic aggregates further converted into non-toxic amyloids which were successfully amplified by PMCA method, providing the first evidence for the in vitro propagation of synthetic a-Syn aggregates. These results suggest an important role for protein dimerization in aggregation and amyloidogenesis, and therefore, in the pathology of PD and prion disease. The similarities between aggregation, amyloidogenesis and toxicity of PrPC and ct-Syn provide further evidence on the existance of a prion-like mechanism in all neurodegenerative disorders. // Résumé: Les maladies neurodégénératives sont associées à la perte progressive des propriétés structurales ou fonctionnelles des neurones, ce qui engendre la mort des cellules. De récentes études indiquent que tous les désordres neurodégénératifs, sporadiques ou transmissibles, peuvent avoir un mécanisme pathologique commun au niveau moléculaire. Ce dispositif commun se compose de l'agrégation de protéines, de la propagation des agrégats, et de l'accumulation d’agrégats toxiques dans les cellules neuronales, menant à l'apoptose et à la neurotoxicité cellulaire. Les maladies neurodégénératives peuvent affecter la pensée abstraite, les mouvements habiles, les sentiments émotifs, la connaissance, la Mémoire et d'autres capacités cognitives. Ce groupe divers de maladies inclut la maladie d'Alzheimer (AD), de Parkinson (PD), de Huntington (HD), les maladies à prions ou encéphalopathies spongiformes transmissibles (TSEs) et la sclérose latérale amyotrophique (ALS). [symboles non conformes]
55

Einfluss des Gravitational Platelet Separation System (GPS®-System) auf den postoperativen klinischen Verlauf nach medianer Sternotomie bei herzchirurgischem Eingriff / Influence of the Gravitational Platelet Separation System (GPS®-System) on the postoperative clinical course following median sternotomy in cardiothoracic surgery

Drescher, Andreas 06 August 2019 (has links)
No description available.
56

Characterization of Shadoo and DPPX: Two Proteins of Potential Relevance to Prion Biology

Watts, Joel Christopher 01 August 2008 (has links)
Prion diseases are fatal neurodegenerative disorders of humans and animals. The prion hypothesis states that PrPSc, a misfolded conformational isoform of the cellular prion protein (PrPC), is the sole component of the infectious particle. Many open questions exist in prion biology including the cellular role of PrPC, the potential involvement of auxiliary factors in prion replication, and the mechanism of PrPSc-induced toxicity in prion disease. The identification of novel prion-like proteins and authentic in vivo prion protein-interacting proteins would certainly assist the process of demystifying these unsolved mysteries. Accordingly, two newly-identified proteins with potential relevance to prion protein biology, Shadoo and DPPX, were selected for biochemical and functional characterization. Shadoo, a hypothetical prion-like protein, is revealed as being a glycoprotein which possesses many overlapping properties with PrPC including neuronal expression, C1-like endoproteolytic processing, and the ability to protect against apoptotic stimuli in cerebellar neurons. Shadoo loosely resembles the disordered N-terminal domain of PrPC and consistent with this notion, Shadoo appears to lack a well-defined structure. Remarkably, Shadoo levels in the brains of mice with clinical prion disease are significantly decreased suggesting that Shadoo may be inherently linked to prion replication or prion disease pathogenesis. These experiments define Shadoo as the third member of the prion protein family and, because of its functional similarities to PrPC, Shadoo may be a useful tool for deciphering the in vivo function of PrPC. DPPX, a neuronal type II transmembrane protein, is demonstrated to be the first protein capable of interacting with all three members of the prion protein family (PrPC, Doppel, and Shadoo) in vivo. Complex formation between prion proteins and DPPX appears to be mediated by multiple binding sites. When coupled with high levels of DPPX expression in cerebellar granular neurons, DPPX is a strong candidate for mediating phenotypic interactions between prion proteins in cerebellar cells. Thus, Shadoo and DPPX comprise two new entry points for studying prion proteins. Further investigation of the roles of Shadoo and DPPX in both the cell biology of prion proteins and prion disease may yield important clues to these enigmatic topics.
57

Characterization of Shadoo and DPPX: Two Proteins of Potential Relevance to Prion Biology

Watts, Joel Christopher 01 August 2008 (has links)
Prion diseases are fatal neurodegenerative disorders of humans and animals. The prion hypothesis states that PrPSc, a misfolded conformational isoform of the cellular prion protein (PrPC), is the sole component of the infectious particle. Many open questions exist in prion biology including the cellular role of PrPC, the potential involvement of auxiliary factors in prion replication, and the mechanism of PrPSc-induced toxicity in prion disease. The identification of novel prion-like proteins and authentic in vivo prion protein-interacting proteins would certainly assist the process of demystifying these unsolved mysteries. Accordingly, two newly-identified proteins with potential relevance to prion protein biology, Shadoo and DPPX, were selected for biochemical and functional characterization. Shadoo, a hypothetical prion-like protein, is revealed as being a glycoprotein which possesses many overlapping properties with PrPC including neuronal expression, C1-like endoproteolytic processing, and the ability to protect against apoptotic stimuli in cerebellar neurons. Shadoo loosely resembles the disordered N-terminal domain of PrPC and consistent with this notion, Shadoo appears to lack a well-defined structure. Remarkably, Shadoo levels in the brains of mice with clinical prion disease are significantly decreased suggesting that Shadoo may be inherently linked to prion replication or prion disease pathogenesis. These experiments define Shadoo as the third member of the prion protein family and, because of its functional similarities to PrPC, Shadoo may be a useful tool for deciphering the in vivo function of PrPC. DPPX, a neuronal type II transmembrane protein, is demonstrated to be the first protein capable of interacting with all three members of the prion protein family (PrPC, Doppel, and Shadoo) in vivo. Complex formation between prion proteins and DPPX appears to be mediated by multiple binding sites. When coupled with high levels of DPPX expression in cerebellar granular neurons, DPPX is a strong candidate for mediating phenotypic interactions between prion proteins in cerebellar cells. Thus, Shadoo and DPPX comprise two new entry points for studying prion proteins. Further investigation of the roles of Shadoo and DPPX in both the cell biology of prion proteins and prion disease may yield important clues to these enigmatic topics.
58

Preservação de plasma rico em plaquetas de coelhos em nitrogênio líquido e freezer

Vieira, Raissa Brauner Kamla 23 February 2017 (has links)
Plasma rico em plaquetas (PRP) é um subproduto sanguíneo obtido por meio de centrifugações e subsequente separação dos elementos sanguíneos. As plaquetas são responsáveis pela produção e liberação de fatores que favorecem o reparo de diferentes tecidos. Este estudo teve como objetivo comparar e avaliar a viabilidade do PRP após congelamento e criopreservação. Foram utilizados 12 coelhos da raça Nova Zelândia adultos saudáveis para coleta de 12 mL de sangue de cada animal por meio de punção cardíaca. Para protocolo de congelamento foi usada centrífuga Centribio 14 cm de diâmetro, e para o protocolo de preservação em nitrogênio foi usada centrífuga fria a 4ºC 18 cm de diâmetro Centurion Scientific K3 Series. Foram feitas, para ambos os protocolos, duas centrifugações, a 2000 rpm por 20 minutos cada. O PRP obtido foi submetido a dois protocolos de preservação, sendo um o congelamento em freezer a -20°C (protocolo F) e outro a redução gradativa de temperatura à criopreservação a -196°C (protocolo N), usando DMSO a 6% como crioprotetor e analisados nos momentos zero (0) e decorridos 15, 30, 45 e 60 dias de preservadas. Foram realizadas contagens em câmara de Neubauer, análises através dos testes do 3-(4,5-dimetiltiazol-2yl)-2,5-difenil brometo de tetrazolina (MTT) para viabilidade celular, eletroforese SDS-PAGE para identificação proteica e cultura para fungos e mesófilas. Verificou-se que o PRP preservado sob protocolo N apresentou maior número de plaquetas preservadas quando comparado ao protocolo F (p<0,05). Ao teste de MTT o protocolo N exibiu maior variação metabólica, porém, maior viabilidade das plaquetas, confirmado pela eletroforese, onde observou-se prevalência de proteínas nas amostras criopreservadas. Ao teste microbiológico, todas as amostras se mostraram livres de contaminantes de origem bacteriana e fúngica. O método de preservação em nitrogênio líquido foi mais eficaz do que em freezer, mantendo as plaquetas metabolicamente mais ativas, as proteínas de ação reparadora tecidual e a esterilidade. / Platelet rich plasma (PRP) is a blood by-product obtained from centrifugations and subsequent separation of blood elements. Platelets are responsible for the production and release of factors that favor the repair of different tissues. This study aimed to compare and evaluate the viability of PRP after freezing and cryopreservation. Twelve healthy adult New Zealand rabbits were used to collect 12 mL of blood from each animal through cardiac puncture. Centribio centrifuge with 14 cm in diameter was used for the freezing protocol, and Centurion Scientific K3 Series cold centrifuge at 4 ° C 18 cm in diameter was used for the nitrogen preservation protocol. For both protocols, two centrifugations were done at 2000 rpm for 20 minutes each. The obtained PRP was submitted to two preservation protocols, one being the freezing at -20 ° C (protocol F) and the other the gradual reduction of temperature to cryopreservation at -196 ° C (protocol N). In both protocols were used 6% DMSO as cryoprotectant and analysis made at zero (0) times and after 15, 30, 45 and 60 days after preserved. Neubauer chamber counts were performed, tests of 3- (4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazoline bromide (MTT) for cell viability, SDS-PAGE electrophoresis for protein identification and culture for fungi and mesophiles. It was verified that PRP preserved under N protocol had a higher number of platelets preserved when compared to protocol F (p <0.05). In the MTT test, the N protocol showed greater metabolic variation, but a higher platelet viability, confirmed by electrophoresis, where protein prevalence was observed in the cryopreserved samples. At the microbiological test, all the samples were free of contaminants of bacterial and fungal origin. The preservation method in liquid nitrogen was more effective than in freezer, keeping platelets more active metabolically, tissues repairing proteins presents and sterility. / Dissertação (Mestrado)
59

Do integralismo ao udenismo: a trajetória política de Raymundo Padilha

Oliveira, Alexandre Luís de 06 June 2014 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-19T14:05:29Z No. of bitstreams: 1 alexandreluizdeoliveira.pdf: 1696026 bytes, checksum: 4779a19194b2ef6c5aaac97ec5a3649e (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-26T13:48:38Z (GMT) No. of bitstreams: 1 alexandreluizdeoliveira.pdf: 1696026 bytes, checksum: 4779a19194b2ef6c5aaac97ec5a3649e (MD5) / Made available in DSpace on 2016-02-26T13:48:38Z (GMT). No. of bitstreams: 1 alexandreluizdeoliveira.pdf: 1696026 bytes, checksum: 4779a19194b2ef6c5aaac97ec5a3649e (MD5) Previous issue date: 2014-06-06 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta dissertação analisa a trajetória de Raymundo Padilha, último Governador do Estado do Rio de Janeiro antes da fusão com a Guanabara. Seu objetivo é compreender a trajetória política de Padilha, levando em conta as redes nas quais se inseriu como político e onde caminhou pelas varias nuanças da direita brasileira, permanecendo por mais de duas décadas. A primeira parte se dedica aos primeiros passos de Padilha na política e sua participação na Ação Integralista Brasileira. Podemos perceber a atuação de Padilha desde os primeiros momentos de filiação na AIB de Petrópolis – RJ até sua chegada ao comando do núcleo fluminense. A segunda parte analisou a atuação de Padilha durante o Estado Novo varguista, período em que a AIB esteve na ilegalidade e Plínio Salgado, chefe e fundador do integralismo, esteve exilado em Portugal. Padilha assumiu nesse momento uma posição importante perante aos integralistas no Brasil, ele atuou como porta-voz de Plínio e ajudou na formação do Partido de Representação Popular. A terceira parte abrange o período parlamentar de Padilha, tendo como partida o ano de 1952 quando assumiu o cargo de Deputado Federal do Rio de Janeiro pelo PRP. Este capítulo também analisa sua atuação na União Democrática Nacional – UDN e posteriormente na Aliança Renovadora Nacional – ARENA. Padilha chegou ao cargo de Governador do Estado do Rio de Janeiro em 1970 e ocupou essa posição até 1975. Após esse período se afastou da política. / This academic research analyzes Raymundo Padilha’s trajectory, last Governor of the State of Rio de Janeiro before the merger with Guanabara. The research intended to understand, through the analysis of the trajectory of Padilha and taking into account the networks in which he entered as articulated in political and Brazilian right, staying for more than two decades in political activity. The first part is dedicated to the first steps of Padilha in politics and his participation in the Brazilian Integralist Action - AIB. It is possible to the action of Padilha from the first moments of membership of the AIB Petrópolis - RJ until his arrival at the command statewide. The second part analyzes the work of Padilha during the Estado Novo period in which AIB has been outlawed and Plinio Salgado, head and founder of AIB, in exile in Portugal. Padilha took that moment it an important current position at that moment, as the spokesman of Salgado and helped in the formation of the Party of Popular Representation. The third part analyzes the period of parliamentary Padilha, whose departure the year 1952 when he assumed the position of federal parliamentarian by Rio de Janeiro, as a PRP member. This chapter also analyzes his performance in the National Democratic Union - UDN and later, in the the National Renewal Alliance - ARENA. Padilha came to the office of Governor of the State of Rio de Janeiro in 1970 and held that position until 1975.
60

Identification And Characterization Of Factors That Interact With The PRP24 Gene Product During Pre-mRNA Splicing In Saccharomyces Cerevisiae

Vaidya, Vaijayanti 11 1900 (has links) (PDF)
No description available.

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