<p>Intervertebral disc (IVD) disorders can cause pain and disability for affected individuals. A subset of IVD disorders are thought to originate in the nucleus pulposus (NP) region of the IVD, due to alterations in tissue structure and composition with age and injury. Cells of the NP undergo a phenotypic and behavioral shift with age, changes that are thought to disrupt tissue homeostasis and lead to disc degeneration. There is significant interest in developing biomaterials and strategies to revert adult degenerate NP cells to healthy, young NP cell phenotypes with increased biosynthesis and cell clustering. Studies demonstrate that healthy porcine NP cells interact with laminin proteins through specific integrin subunits on soft substrates in a process that regulates cell morphology and biosynthesis. The central hypothesis of this dissertation is that the engagement of cell-surface adhesion receptors, using laminin-mimetic peptides on a controlled stiffness material, can revert adult degenerate NP cellular phenotype and behaviors to their healthy, biosynthetically active form.</p><p>In the first part of this dissertation, integrin subunits used by adult degenerate human NP cells to attach to laminin were revealed using flow cytometric analyses, function blocking antibodies, and immunohistochemistry. Secondly, NP cell recognition peptides were identified by screening laminin-mimetic peptides for cell attachment. Finally, human NP cells were cultured on peptide functionalized polyacrylamide gels to examine the effect of ligand and substrate stiffness in regulating adult human NP cell phenotype and biosynthesis. </p><p>Findings reveal that adult human NP cells express and utilize integrin subunits α3, α5, and β1 to attach to laminins, in contrast to integrin α6β1 found previously for healthy porcine NP cells. This difference between current and previous findings likely arises from aging-associated difference in NP cells between human and porcine tissues. Select laminin-mimetic peptides, chosen from the literature and informed by NP cell integrin expression, were found to promote significant NP cell attachment in a concentration dependent manner. Finally, a subset of laminin mimetic peptides were found to promote a young NP cell phenotype by increasing cell clustering on soft (0.3 kPa) and stiff (14 kPa) substrates as well as increasing proteoglycan synthesis on soft substrates. </p><p>The studies presented in this dissertation demonstrate that adult degenerate human NP cells attach to laminin proteins in an integrin dependent manner. Furthermore, laminin-mimetic peptides are able to mediate human NP cell attachment at levels comparable to full-length laminin, increase cell clustering when presented on soft and stiff substrates, and can increase NP cell biosynthesis when presented on soft substrates. Utilizing laminin-mimetic peptides may allow for the design of biomaterials that promote a healthy young NP phenotype for a variety of disc therapies.</p> / Dissertation

No description available.

Densification of tailings slurries to mature fine tailings (MFT) is important in the oil sands industry for tailings inventory reduction, pore water recovery and tailings reclamation. The cause of methane release from the tailings pond of Shell Albian Sands (Albian) and the effects this process has on densification of Albian tailings was investigated. Citrate, added to tailings with polyacrylamide and hydrocarbon-diluent, was identified as the methanogenic substrate. Bacterial and Archaeal 16S rRNA gene sequences in Albian MFT were dominated by matches to Rhodoferax, some Clostridia and sulfate-reducing bacteria, and acetoclastic methanogens. Citrate-, diluent-, and polyacrylamide-amendments to Albian MFT did not cause a microbial shift over a 10-month laboratory incubation period. A potential pathway for microbial methane production in Albian MFT is proposed. Methane production and release from citrate-amended Albian MFT correlated to accelerated densification. Though diluent and polyacrylamide did not affect methanogenesis, they potentially affect gas bubble formation and release. / Microbiology and Biotechnology

Thesis (M.S.)--Rochester Institute of Technology, 1989. / Includes bibliographical references (leaves 81-83).

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 82-88).

Techn. Universiẗat, Diss., 2001--Darmstadt.

Submitted by Aline Diorio Dos Santos (aline_sduarte@yahoo.com.br) on 2018-06-08T13:12:54Z No. of bitstreams: 1 Dissertação_Aline_23_4_1.pdf: 4336751 bytes, checksum: b04bc967fc2ebdfb6b4208fbc09f7000 (MD5) / Approved for entry into archive by Ana Paula Santulo Custódio de Medeiros null (asantulo@rc.unesp.br) on 2018-06-08T16:42:40Z (GMT) No. of bitstreams: 1 santos_ad_me_rcla.pdf: 4221486 bytes, checksum: 64fef6cda169d205f99769d9b9e4f33f (MD5) / Made available in DSpace on 2018-06-08T16:42:40Z (GMT). No. of bitstreams: 1 santos_ad_me_rcla.pdf: 4221486 bytes, checksum: 64fef6cda169d205f99769d9b9e4f33f (MD5) Previous issue date: 2018-04-23 / Um dos materiais presentes nos lodos oriundos das estações de tratamento (LETAs) é o polímero denominado Poliacrilamida (PAM). Acredita-se que o mesmo seja inerte no solo, porém sua degradação pode estar associada a presença de compostos nitrogenados no solo, como amônio, nitratos e nitritos. Assim, é essencial avaliar a degradação de polímeros no sistema de tratamento de água que auxiliará na seleção e uso de produtos poliméricos no tratamento de água potável. Através da revisão bibliográfica apresentada neste trabalho, foi elaborado um Modelo Conceitual para a disposição de LETAs em aterro, com enfoque na degradação de poliacrilamidas e sua degradação em compostos nitrogenados, validando-o através de dados observados em estudo de caso. Conforme o Modelo Conceitual elaborado, pela via aeróbia, em que os processos de nitrificação podem ser observados, esperavam-se menores valores de pH (resultado da liberação de íons H+), assim como ambiente oxidante para ocorrência do processo de nitrificação (meio aeróbio necessita de oxigênio disponível), enquanto na área fora da zona de nitrificação, esperava-se maior valores de pH, presença maior de OD e maiores valores de Eh, uma vez que o oxigênio não estará sendo consumido pelas bactérias nitrificantes, podendo ainda haver incremento de OD pela recarga do aquífero através das precipitações. Observa-se outra via de degradação anaeróbia, pela reação anamox, em que amônio é oxidado e nitrito reduzido, liberando gás nitrogênio, em ambiente redutor. Adicionalmente, podem ser observados o íon amônio e óxido de manganês e hidróxido de ferro (abundantes no solo) sendo oxidados a nitrogênio gasoso, consumindo íons H+ no meio. A flutuação do nível de água no aquífero pode influenciar as concentrações observadas, através da recarga do aquífero, devido a precipitação e infiltração da água no solo, a espessura do aquífero livre pode se tornar maior, entrando em contato com camadas superficiais de PAM, ocorrendo maior lixiviação dos íons presentes nestas camadas e aumento das concentrações, havendo incremento de massa. Esse fenômeno pode ocorrer em conjunto com os processos biológicos citados, ocorrendo alternância da dissociação dos compostos nitrogenados por meio aeróbio e anaeróbio, conforme OD disponível no meio. Torna-se, portanto, indispensável a discussão sobre quais tipos de polieletrólitos podem ser utilizados no sistema de tratamento de água, pois conforme dados apresentados neste trabalho, a poliacrilamida presente no LETA pode degradar-se em amônio e por sua vez em nitrato por via aeróbia, contaminando o aquífero local, não se apresentando como resíduo inerte como preconizado pelo mercado e alguns autores. / One of the materials present in the sludge originated from water treatment is the polymer polyacrylamide, which some people believes is inert in the soil however its degradation may be associated with nitrogenous compounds in the soil, such as ammonium, nitrates and nitrites. So, it is essential to evaluate the degradation of polymers in the water treatment system due to it will assist in the selection and use of polymer products in the water treatment. Through the bibliographic review presented, a Conceptual Model for the disposition of sludge from water treatment in soil was developed, with the focus on the degradation of polyacrylamides and their degradation in nitrogenous compounds, validating it through data observed in a case study. According to the Conceptual Model elaborated, considering the aerobic route, where the nitrification processes can be observed, were expected lower pH values and oxidizing environment, while in the area outside the nitrification zone were expected higher pH values, presence of dissolved oxygen and reduction environment, once oxygen will not be consumed by nitrifying bacteria and also oxygen could be increased by water from precipitation which recharges the aquifer. Another anaerobic degradation route is observed, considering the anamox reaction, where ammonia is oxidized and nitrite reduced, releasing nitrogen gas, in a reducing environment. In addition, ammonium ion plus manganese oxide plus iron hydroxide can be oxidized to a vapour nitrogen, consuming hydrogen ions. The water level fluctuation in the aquifer can influence the observed concentrations, through the recharge of the aquifer, due to precipitation and infiltration of the water in the soil, the thickness of the free aquifer can become larger, coming into contact with sludge, occurring higher lixiviation of the ions present in these layers and increasing of the concentrations and mass. This phenomenon can occur together with the biological processes, occurring alternation of dissociation of the nitrogen compounds by aerobic and anaerobic, according to dissolved oxygen available. Therefore, it is essential to discuss what types of polyelectrolytes can be used in the water treatment system, due to according to data presented, the polyacrylamide present in the sludge can degrade in ammonium and in turn in nitrate by aerobic process, contaminating the local aquifer, not presenting as inert residue as recommended by the market and some authors.

Made available in DSpace on 2015-04-09T12:28:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-08Bitstream added on 2015-04-09T12:48:01Z : No. of bitstreams: 1 000814587.pdf: 233099 bytes, checksum: 86c73283cfc6d5c2954be91ce17d3f29 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Endotoxins are often found in high concentration in the peritoneal fluid from horses with acute gastrointestinal disease and blood of septicemic foals. The conditions mentioned earlier can lead to inflammatory processes and cause changes in the concentrations of acute phase proteins. The objectives of this study were to determine by means of polyacrylamide gel electrophoresis (SDS-PAGE), the concentrations of acute phase proteins (transferrin, ceruloplasmin, albumin, haptoglobin and acid glycoprotein) in serum and peritoneal fluid of horses submitted to experimental endotoxemia and evaluate the possible effects of the administration of lidocaine on the production of these proteins after intraperitoneal injection of endotoxin in these animals. To this end, 12 animals were distributed in two groups, control which was treated with 0.9% NaCl solution and the experimental which was treated with continuous infusion for 6 hours of 2% lidocaine solution. It is concluded that in this experimental model the intraperitoneal administration of endotoxin caused an increase in the concentrations of peritoneal transferrin, ceruloplasmin and haptoglobin in the control group, of albumin in both groups, and the acid glycoprotein in the group treated with infusion of lidocaine. However, the absence of changes in the concentrations of serum ceruloplasmin, serum albumin, haptoglobin and acidic glycoprotein indicate that the amount of the circulatory endotoxin was not enough to alter serum concentrations of these proteins. The continuous infusion of lidocaine interfered in peritoneal acute phase proteins values and had an anti-endotoxemic effect / FAPESP: 2009/15683-0

Resumo:As endotoxinas são frequentemente detectadas em alta concentração no líquido peritoneal de equinos com doença gastrintestinal aguda e no sangue de potros septicêmicos. As condições citadas anteriormente podem levar a processos inflamatórios e provocar alterações nas concentrações de proteínas de fase aguda. Os objetivos deste estudo foram determinar, por meio de eletroforese em gel de poliacrilamida (SDS-PAGE), as concentrações de proteínas de fase aguda (transferrina, ceruloplasmina, albumina, haptoglobina e glicoproteína ácida) no soro e no líquido peritoneal de equinos submetidos à endotoxemia experimetal, e avaliar os possíveis efeitos da administração da lidocaína sobre a produção destas proteínas depois da injeção intraperitoneal de endotoxina nestes animais. Para tanto, foram utilizados 12 animais distribuídos em dois grupos, o controle, tratado com solução de NaCl a 0,9%, e o experimental, tratado com infusão contínua de solução de lidocaína a 2% por 6 horas. Conclui-se que neste modelo experimental a administração intraperitoneal de endotoxina causou o aumento nas concentrações peritoneais de transferrina, ceruloplasmina e haptoglobina no grupo controle, da albumina em ambos os grupos, e da glicoproteína ácida no grupo tratado com infusão de lidocaína. Porém a ausência de alterações nas concentrações séricas de ceruloplasmina, albumina, haptoglobina e glicoproteína ácida indicam que a quantidade de endotoxina que chegou à corrente circulatória não foi suficiente para alterar as concentrações séricas destas proteínas. A infusão contínua de lidocaína interferiu nos valores peritoneais das proteínas mensuradas, tendo efeito anti-endotoxêmico / Abstract:Endotoxins are often found in high concentration in the peritoneal fluid from horses with acute gastrointestinal disease and blood of septicemic foals. The conditions mentioned earlier can lead to inflammatory processes and cause changes in the concentrations of acute phase proteins. The objectives of this study were to determine by means of polyacrylamide gel electrophoresis (SDS-PAGE), the concentrations of acute phase proteins (transferrin, ceruloplasmin, albumin, haptoglobin and acid glycoprotein) in serum and peritoneal fluid of horses submitted to experimental endotoxemia and evaluate the possible effects of the administration of lidocaine on the production of these proteins after intraperitoneal injection of endotoxin in these animals. To this end, 12 animals were distributed in two groups, control which was treated with 0.9% NaCl solution and the experimental which was treated with continuous infusion for 6 hours of 2% lidocaine solution. It is concluded that in this experimental model the intraperitoneal administration of endotoxin caused an increase in the concentrations of peritoneal transferrin, ceruloplasmin and haptoglobin in the control group, of albumin in both groups, and the acid glycoprotein in the group treated with infusion of lidocaine. However, the absence of changes in the concentrations of serum ceruloplasmin, serum albumin, haptoglobin and acidic glycoprotein indicate that the amount of the circulatory endotoxin was not enough to alter serum concentrations of these proteins. The continuous infusion of lidocaine interfered in peritoneal acute phase proteins values and had an anti-endotoxemic effect / Orientador: Francisco Leydson Formiga Feitosa / Banca: Marcos Pinheiro Franque / Banca: Taciana Rabelo Ramalho Ramos / Banca: Paulo Sérgio Patto dos Santos / Banca: Juliana Regina Peiró / Doutor

Orientador: Rosângela Barros Zanoni Lopes Moreno / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-20T08:17:10Z (GMT). No. of bitstreams: 1 Lopes_LeandroFreitas_M.pdf: 2721752 bytes, checksum: 3eff0862fda0329e774f1b5e9dbeaf25 (MD5) Previous issue date: 2012 / Resumo: A perfuração de poços de petróleo pode danificar fortemente a formação, incluindo a região de interesse: o reservatório. Perfurar sem que se danifique o reservatório caracteriza-se como um grande desafio, e por isso, tem sido estimulado o desenvolvimento de tecnologias de fluidos e otimização de processos de perfuração, incluindo, por exemplo, o projeto de fluidos com vistas à minimização de dano. Tem sido relatado que, um planejamento detalhado desde o projeto do fluido pode ajudar a minimizar o dano de formação e contribuir para uma melhor restauração da produtividade do poço. Este trabalho é focado na análise do dano de formação causado pela invasão de fluidos de perfuração de base água em reservatórios de petróleo areníticos. Os fluidos foram preparados com os seguintes componentes: sal, polímero e argila. O sal utilizado foi o iodeto de sódio (NaI) na concentração de 150000 ppm; o polímero foi, ora a poliacrilamida parcialmente hidrolisada (PHPA), ora a Goma Xantana (GX), e a argila utilizada foi a bentonita. Para simular o reservatório foram utilizadas amostras pequenas de arenito Botucatu de alta permeabilidade. As amostras, inicialmente 100% saturadas com óleo mineral (~ 24 cp @23º C), foram submetidas a um processo de invasão, simulando-se uma perfuração sobrebalanceada, e a um fluxo reverso de óleo, simulando-se o início de produção de petróleo, aplicando-se para ambos um diferencial de pressão manométrica de 20 psi (~ 138 kPa). A concentração de polímero foi de 3,5 lb/bbl (10 g/l ou 10000 ppm) quando preparados com PHPA, e de 3,0 lb/bbl (8,6 g/l ou 8600 ppm) quando preparados com GX. A concentração de bentonita variou de 2,5%, 2,0%, 1,5% e 0,0% em massa para ambos os polímeros, resultando em um total de oito fluidos preparados. Foram avaliadas a redução da permeabilidade e da razão de produtividade das amostras durante a invasão dos fluidos, bem como o retorno destas quando aplicado um fluxo reverso de óleo. Os resultados obtidos mostraram que os fluidos que continham argila resultaram em uma menor invasão ou perda de fluido para a formação do que os fluidos que continham somente polímero. Além disso, a concentração de argila influenciou nos resultados obtidos de redução de permeabilidade e do retorno da razão de produtividade. Quanto maior a concentração de argila, menor a invasão de filtrado, porém, o retorno da razão de produtividade também foi menor, evidenciando o potencial de dano da mesma. Os fluidos preparados com PHPA, quando injetados, resultaram em uma maior invasão de filtrado do que os fluidos preparados com GX, porém o retorno da razão de produtividade também foi maior, mostrando que estes fluidos, apesar de invadirem mais, danificaram menos as amostras. Os fluidos preparados com GX tamponaram as gargantas de poro mais rapidamente, e em alguns casos, por completo. O fato de tamponar ou não os poros das amostras teve influência no retorno da razão de produtividade, sendo observado maior retorno nas amostras não tamponadas em relação àquelas tamponadas por completo. Os resultados apresentados aqui podem contribuir para a tecnologia de fluidos de perfuração e avaliação do projeto do fluido, com vistas à minimização de dano à formação e manutenção da produtividade do reservatório o mais próximo da original / Abstract: Oil well drilling can strongly damage the formation, including the interest region: the reservoir. Drilling without damaging the reservoir is characterized as a hard challenge, and therefore, the development of technologies and optimization process has been stimulated, including, for example, the fluid design in order to minimize damage. It has been reported that a detailed fluid management plan addressing fluid design can help to minimize formation damage and contribute to a better well productivity restoration. This work is focused on formation damage analysis caused by water-based drilling fluids invasion in sandstone oil reservoirs. Fluids were prepared including the following components: salt, polymer and clay. It was used a 150,000 ppm concentration of sodium iodide (NaI) as salt, either a partially hydrolyzed polyacrylamide (HPAM) or a xanthan gum (XG) as polymer, and bentonite as clay. To simulate the reservoir, small samples of high permeability Botucatu sandstone were used. The samples, 100% initially saturated with mineral oil (~ 24 cp @ 23 ° C), were submitted to an invasion process, simulating an overbalanced drilling, and to an oil reverse flow, simulating the oil production beginning, applying to both a 20 psi (~ 138 kPa) gauge pressure difference. The polymer concentration was 3.5 lb/bbl (10 g/l or 10,000 ppm) when prepared with HPAM, and 3.0 lb/bbl (8.6 g/l or 8,600 ppm) when prepared with XG. The bentonite concentration ranged from 2.5%, 2.0%, 1.5% and 0.0% weight for both polymers, resulting in eight tested fluids. During fluids invasion, the permeability impairment and productivity ratio of the samples were evaluated, as well as their return when applied to an oil reverse flow. Obtained results pointed that fluids containing clay resulted in a lower fluid loss to the formation than fluids containing only polymer. Moreover, clay concentration influenced on permeability impairment and on obtained results for the productivity ratio return. The higher is clay concentration, the less is fluid invasion, however, productivity ratio return was also lower, highlighting the clay damage potential. HPAM fluids, when injected, resulted in a higher fluid invasion than XG fluids, but productivity ratio return was also higher, pointing that HPAM fluids, even though had invaded more, the damage was lower. XG fluids blocked pore throats faster and, in some cases, completely. The blocking effect on samples pores influenced on productivity ratio return, i. e., higher return was obtained for samples that weren't blocked. Results presented here may contribute to drilling fluids technology, fluid design evaluation and formation damage minimization aiming to keep the reservoir productivity closer to the original / Mestrado / Reservatórios e Gestão / Mestre em Ciências e Engenharia de Petróleo