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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.
71

Alluvial stratigraphy and soil formation at Cox Ranch Pueblo, New Mexico

Vanbuskirk, Stephanie, January 2004 (has links) (PDF)
Thesis (M.A. in anthropology)--Washington State University. / Includes bibliographical references.
72

Expressão de aromatase no endométrio e seu papel no desenvolvimento de patologias uterinas / Programa de pós-graduação em medicina e saúde

Maia Filho, Hugo da Silva January 2013 (has links)
p. 1-78 / Submitted by Antonio Geraldo Couto Barreto (ppgms@ufba.br) on 2013-10-02T18:05:28Z No. of bitstreams: 1 Hugo Maia.pdf: 4715178 bytes, checksum: 067aa12a42b4bcfc56dd4ac8e4173ab8 (MD5) / Approved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-10-02T22:07:53Z (GMT) No. of bitstreams: 1 Hugo Maia.pdf: 4715178 bytes, checksum: 067aa12a42b4bcfc56dd4ac8e4173ab8 (MD5) / Made available in DSpace on 2013-10-02T22:07:54Z (GMT). No. of bitstreams: 1 Hugo Maia.pdf: 4715178 bytes, checksum: 067aa12a42b4bcfc56dd4ac8e4173ab8 (MD5) Previous issue date: 2013 / A expressão de aromatase no endométrio eutópico é desencadeada pela constante exposição a mediadores inflamatórios, que são produzidos durante o período menstrual e proliferativo do ciclo menstrual. A presença de aromatase nas células endometriais é um dos fatores desencadeantes de endometriose na cavidade peritonial, miomas submucosos e intra-murais, pólipos endometriais e adenomiose. Diante disso, esta tese tem como objetivo investigar os efeitos da expressão de aromatase no endométrio, compreendendo a ação desta e como se evitar o desenvolvimento das patologias endometriais. Para isso, foram analisados resultados de biopsias de pacientes submetidas à histerectomia e laparoscopia, no período de janeiro de 2007 a março de 2009 de dois centros de tratamento da cidade de Salvador- Bahia, as quais apresentavam algumas das patologias citadas, seguindo os critérios da American Sciety of Reproductive Medicine. Por fim concluiu-se que a diminuição da expressão de aromatase induzida por progestínicos foi acompanhada por uma redução na expressão de enzimas como ciclooxigenase-2 (Cox-2) ou de fatores angiogênicos como VEGF no endométrio. A inflamação no endométrio também foi reduzida pela progesterona ou por progestínicos e este mecanismo envolveu a inibição da ativação do NF-kappa B. Estes achados sustentam a hipótese do papel que teriam os progestínicos como agentes anti-aromatase e anti-inflamatórios no manejo atual da endometriose e de outras patologias ginecológicas. E que o uso contínuo de contraceptivos orais combinados contendo gestodeno ou o uso de sistemas intra-uterinos liberadores de levonorgetsrel são efetivos na prevenção tanto da recorrência de endometriose, quanto da menorragia associada a miomas. / Salvador
73

Evaluating multiple endpoints in heart failure clinical trials

Yang, Yijun 12 March 2016 (has links)
The selection of the best response variables in a clinical trial is often not straightforward; the primary endpoint of a trial should be clinically relevant, directly related to the primary objective of the trial, and with favorable efficiency to detect the treatment benefit with a reasonable sample size and duration of the trial. With the recent success in the management of heart failure, the mortality rate has dropped significantly compared to two decades ago, and patients with heart failure have high rates of hospitalization and morbid complications along with multiple symptoms and severe limitations in daily activities. Although mortality still remains important as a measure of the clinically relevant benefit and the safety of the intervention, with the low event rate of mortality, it requires large and longer clinical trials to detect treatment benefit of new intervention using mortality as the sole primary endpoint. Thus most heart failure trials use the combined endpoint of death and a second efficacy outcome, such as hospitalizations. This is often analyzed with time-to-first-event survival analysis which ignores possible subsequent hospitalization events and treating the death and first hospitalization equally in the importance and hierarchy of clinical relevance. Accounting for the recurrent events or subsequent death after the hospitalization(s) provides more detailed information on the disease-control process and treatment benefit. In this dissertation we propose a hierarchical endpoint with death in the higher priority and number of hospitalization events in the lower priority as primary endpoint to assess experimental treatment benefit versus a control using a non-parametric generalized Gehan-Wilcoxon test. In addition to the hierarchical endpoint, we also evaluated assessment of experimental treatment benefit on recurrent events with a multi-state model using extended stratified Cox model, considering the multi-states in which patients might transition during the study. We compared the false positive rate and power of the above mentioned methods with the composite endpoint approach and recurrent event endpoint approach analyzed using Andersen-Gill, WLW, and PWP models in simulation studies. Finally we applied all evaluated procedures to the Digitalis Investigation Group (DIG) trial.
74

Papel de caveolina-1 na produção de mediadores inflamatórios / Papel de caveolina-1 na produção de mediadores inflamatórios

Zampier, Carolina da Paz January 2012 (has links)
Submitted by Alessandra Portugal (alessandradf@ioc.fiocruz.br) on 2013-10-01T21:53:22Z No. of bitstreams: 1 Carolina da Paz Zampier.pdf: 2134379 bytes, checksum: d822f378a88e2cf44b02c5ea60f52ea0 (MD5) / Made available in DSpace on 2013-10-01T21:53:22Z (GMT). No. of bitstreams: 1 Carolina da Paz Zampier.pdf: 2134379 bytes, checksum: d822f378a88e2cf44b02c5ea60f52ea0 (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil / A caveolina-1 (Cav-1), uma proteína essencial para a formação de cavéolas, apresenta atividade na modulação da sinalização intracelular. Cav-1 é capaz de interagir com diversas proteínas através de seu domínio CSD (caveolin scaffolding domain) e, em geral, essa interação leva à inibição das proteínas associadas. O peptídeo CSD tem sido utilizado como um mimético de Cav-1 em relação à sua capacidade modulatória sobre a atividade de outras proteínas. Recentemente, tem sido mostrado que Cav-1 é capaz de modular a resposta inflamatória em diversos aspectos. Neste trabalho, examinamos o papel de Cav-1 na regulação da síntese de mediadores inflamatórios por macrófagos. O lipopolissacarídeo (LPS) de E.coli, um protótipo de estímulo inflamatório, foi capaz de induzir a expressão de Cav-1 e Cox-2 em macrófagos peritoneais in vitro. Estas proteínas são induzidas em um curso temporal semelhante, sendo detectadas por Western blot a partir de 3h com níveis de expressão crescentes até 18h. Por imunofluorescência, observamos que Cav-1 e Cox-2 apresentam um padrão de expressão mutualmente exclusivo em macrófagos estimulados com LPS. Mostramos por Western blot que a expressão de Cox-2 é induzida por LPS e que o tratamento com CSD leva à inibição da expressão de Cox- 2, mas não de Cox-1. Observamos, também, a redução parcial dos níveis de PGE2 no sobrenadante de macrófagos estimulados com LPS e tratados com CSD. O tratamento com o peptídeo CSD também foi capaz de reduzir os níveis de IL-1, IL- 6, e IL-12 induzidos por LPS. O LPS induz o aumento da expressão e fosforilação de STAT-1. A fosforilação de STAT-1 foi diminuída após o tratamento com CSD, indicando que Cav-1 modula negativamente a ativação de STAT-1. Estudos posteriores são necessários para complementar os dados obtidos até o momento para esclarecer os mecanismos de modulação da síntese de mediadores inflamatórios por Cav-1. Em conclusão, Cav-1 apresenta uma atividade inibitória sobre a expressão de Cox-2 e produção dos mediadores inflamatórios PGE2, IL1, IL-6, e IL-12 em macrófagos estimulados com LPS in vitro. O mecanismo de inibição possivelmente envolve inibição da ativação de STAT-1. / Caveolin-1 (Cav-1), a protein essential for the formation of caveolae, shows activity in the modulation of intracellular signaling. Cav-1 can interact with several proteins by its caveolin scaffolding domain (CSD) and, in general, this interaction leads to inhibition of associated proteins. The peptide CSD has been used as a Cav- 1 mimetic in relation to its capacity on the modulatory activity of other proteins. Recently, it has been shown that Cav-1 can modulate the inflammatory response in several respects. We examined the role of Cav-1 in regulating the synthesis of inflammatory mediators by macrophages. Lipopolysaccharide (LPS) from E. coli, a prototype of inflammatory stimulus, was able to induce the expression of Cav-1 and Cox-2 in peritoneal macrophages in vitro. These proteins are induced in a similar time course, being detected by Western blot at 3 hours with increasing levels of expression up to 18 hours. By immunofluorescence, we observed that Cav-1 and Cox-2 have a mutually exclusive pattern of expression in macrophages stimulated with LPS. Western blot analysis showed that the expression of Cox-2 is induced by LPS and that treatment with CSD leads to inhibition of Cox-2 but not Cox-1. We also observed the partial reduction of PGE2 levels in supernatants of macrophages stimulated with LPS and treated with CSD. Treatment with CSD peptide was also able to reduce the levels of IL1, IL-6 and IL-12 induced by LPS. LPS induces increased expression and phosphorylation of STAT-1. The phosphorylation of STAT- 1 was decreased after treatment with the CSD, indicating that a Cav-1 negatively modulates activation of STAT-1. Further studies are needed to supplement the data obtained so far to clarify the mechanisms of modulation of the synthesis of inflammatory mediators by Cav-1. In conclusion, Cav-1 shows an inhibitory activity on Cox-2 expression and production of the inflammatory mediators PGE2, IL1β, IL-6 and IL-12 in macrophages stimulated with LPS in vitro. The mechanism of inhibition possibly involves inhibition of STAT-1 activation.
75

[en] EARLY WARNING OF BANKING FAILURE IN BRAZIL: AN APPLICATION OF DIFFERENT MODELS BETWEEN 1995 AND 1998 / [pt] PREVISÃO DE INSOLVÊNCIA BANCÁRIA NO BRASIL: APLICAÇÃO DE DIFERENTES MODELOS ENTRE 1995 E 1998

MARCIO MAGALHAES JANOT 30 October 2009 (has links)
[pt] O objetivo principal dessa dissertação é identificar, com antecedência, as instituições financeiras mais propensas a se tornarem insolventes, propiciando a implementação de medidas corretivas em tempo hábil e uma alocação mais eficiente dos recursos disponíveis para o acompanhamento direto (on-site) das instituições por parte do Banco Central. Para isso, é necessário a utilização de algum tipo de modelo estatístico, convencionalmente chamado de modelo de early warning, que traduza as características dos bancos em estimativas de risco. Este estudo examina a eficácia de dois tipos de modelos de early warning - o modelo de regressão logística e o modelo de risco proporcional de Cox - em prever o fenômeno de insolvência bancária no Brasil durante o período 1995/1998. Estes modelos basicamente produzem estimativas da probabilidade de um banco, com um dado conjunto de características, sobreviver mais que um determinado intervalo de tempo no futuro, classificando-o como solvente ou insolvente. Apontam também quais as características que mais contribuíram para a insolvência das instituições financeiras. O alto percentual de acerto de classificação dos bancos pelos dois modelos estimados, com a identificação de uma proporção considerável das insolvências com antecedência, indicam que a insolvência bancária é passível de ser prevista no Brasil, sendo recomendável a utilização destes como um instrumento adicional de supervisão do sistema financeiro pelo Banco Central. / [en] The purpose of this study is to identify problem banks and to predict bankrupticies with sufficient lead time for regulators to institute remedial action at these banks. It requires the use of some sort of statistical model, conventionally labeled an early warming model, to translate bank characteristics into estimates of risk. This dissertation presents a pair of early warming models - the logistic regression and the Cox proportional hazards model - and applies them to the prediction of bank failures in Brazil between 1995 and 1998. These models basically produce estimates of the probability that a bank with given set of characteristics will survive longer than some specified length of time into the future. In addiction, these models point out which were the characteristics that most contributed to the bank insolvency. The models identify both failed and healthy banks with a high degree of accuracy. Furthermore, a large proportion of banks that subsequently failed are flagged as potential failures in periods prior their actual demise. This results demonstrate that reasonably accurate early warming models can be built and maintained at relatively low cost. The use of these models could be of great benefit as an additional instrument to the banking supervision activity.
76

The cox collection, the museums of Malawi and the politics of repatriation, 1892-2016

Mtotha, Comfort Tamanda January 2016 (has links)
Magister Artium - MA / A wide range of scholarly inquiries have engaged with how museums all over the world deal with societal issues and the way the public interacts with the museum as a space of transaction and knowledge production. In Malawi, only a small proportion of literature deals with the museums and their relationship to the wider understanding of the country's history and the question of nationalism. However, as modern museums are transforming and reconfiguring themselves in dealing with histories of collection and calls for repatriation of ethnographic objects and human remains from their European counterparts are being made, there is no scholarly work or a nuanced representation on these issues for the Museums of Malawi. This study engages with a biography of a collection to think about museums, nationalism and the politics of repatriation. This biography begins when this collection of objects was collected from the tea plantations of Malawi and how it metamorphosizes from souvenirs to artifacts of rarity and then to "national treasures." The life of the collection is analysed and understood through its multiple journeys from Malawi to Europe and then to the United States of America where it attains a new meaning in a museum before its return to Malawi for a nationalist cause. / Centre for Humanities Research (CHR), University of the Western Cape
77

“Análisis Micro Econométrico de la Decisión de Jubilación en Chile

Atal Chomali, Juan Pablo January 2008 (has links)
No description available.
78

Função renal de cães hígidos tratados com anti-inflamatórios não-esteroidais / Renal function in healthy dogs therapy with anti-inflammatory drugs

Borges, Marina 24 February 2011 (has links)
Made available in DSpace on 2016-01-26T18:55:31Z (GMT). No. of bitstreams: 1 DISSERTACAO.pdf: 506827 bytes, checksum: 85183faa6a63e1b561cacb568f6cf77e (MD5) Previous issue date: 2011-02-24 / The anti-inflammatory nonsteroidal compounds have extremely widespread use in the therapy of small animals, due to their anti-inflammatory and analgesic properties. However, the use of these drugs can produce changes in kidney function. The present study was conducted to assess kidney function in healthy dogs undergoing therapy with anti-inflammatory nonsteroidal compounds. Thirty mongrel dogs, adults, males and females, clinically healthy, were divided randomly into 5 groups (G) of six animals each receiving the following therapies: Gceto ketoprofen, a 2 mg/kg dose (VO), every 24 hours, during 10 days; Gnime nimesulide, 5 mg/Kg, VO, every 24 hours, during 10 days; Gmelo- meloxican, 0.2 mg/Kg on the first day, followed by 0.1 mg/Kg, VO, every 24 hours, 7 days; Geto etodolac, 15 mg/Kg, VO, every 24 hours, 7 days; Gcele- celecoxibe, 5 mg/Kg, VO, every 12 hours, for 20 days. The physical examination and renal function (urinalysis, urinary GGT, creatinine and sodium, serum urea, creatinine, potassium and sodium, and endogenous creatinine clearance) were assessed prior to the treatment, on the 5th and 10th days (T0, T5 and T10) into the treatment in all groups, and also on the 20th day (T20) into the treatment in Gcele. Few changes were observed in urinalysis parameters, only with significant increase in the presence of renal cells in the urine in T5, in the nimesulide group. There was a significant reduction in sodium elimination in the animals urine in the nimesulide group. The clearance values showed significant decrease in the celecoxibe group in T20, in relation to T5. The enzyme GGT urinary showed no variation among groups or moments. Values of sodium, potassium, urea and creatinine serum remained within normal ranges in all times, in the different groups. In conclusion, minimal changes of renal function occur 10 days after therapy on set with NSAIDS nimesulide, after 10 days with ketoprofen, on the 20th days of therapy with celecoxibe in health dogs. / Os anti-inflamatórios não-esteroidais têm uso extremamente difundido na clínica de pequenos animais, devido às suas propriedades analgésicas e anti-inflamatórias. Entretanto, o uso desses fármacos pode produzir alterações da função renal. O presente estudo teve como objetivo avaliar a função renal de cães saudáveis, submetidos à terapia com anti-inflamatórios não-esteroidais não seletivos, COX-2 preferenciais e COX-2 seletivos. Foram utilizados 30 cães, sem raça definida, adultos, machos e fêmeas, clinicamente sadios, divididos aleatoriamente em 5 grupos (G) de 6 animais cada, que receberam as seguintes terapias: Gceto cetoprofeno, na dose de 2 mg/Kg, por via oral (VO), a cada 24 horas, durante 10 dias; Gnime nimesulida, 5 mg/Kg, VO, a cada 24 horas, durante 10 dias; Gmelo - meloxican, 0,2 mg/Kg no primeiro dia, seguido por 0,1 mg/Kg, VO, a cada 24 horas, por 10 dias; Geto etodolaco, 15 mg/Kg, VO, a cada 24 horas, 10 dias; Gcele - celecoxibe, 5 mg/Kg, VO, a cada 12 horas, por 20 dias. O exame físico e a função renal (urinálise; GGT, creatinina e sódio urinários; uréia, creatinina, sódio e potássio séricos; e clearance endógeno de creatinina) foram avaliados antes, aos 5, 10 dias (T0, T5 e T10) de tratamento em todos os grupos, e também aos 20 dias (T20) de tratamento no Gcele. Poucas alterações foram observadas na urinálise, apenas com aumento significativo da presença de células renais na urina no T5 e T10 em relação ao T0, no grupo nimesulida. Houve redução significativa da eliminação de sódio na urina, nos animais do grupo nimesulida, no T5. Os valores de clearance foram os mais baixos no grupo Cetoprofeno no T10, e revelaram diminuição significativa no grupo Celecoxibe no T20, em relação ao T5. A enzima GGT urinária não apresentou variação entre grupos ou momentos. Valores de sódio, potássio, uréia e creatinina séricos mantiveram-se dentro da normalidade em todos os momentos nos diferentes grupos. Conclui-se que, em cães hígidos, alterações mínimas da função renal ocorrem aos cinco dias de terapia com o AINE nimesulida, aos dez dias com cetoprofeno, e aos vinte dias de terapia com celecoxibe.
79

Função renal de cães hígidos tratados com anti-inflamatórios não-esteroidais / Renal function in healthy dogs therapy with anti-inflammatory drugs

Borges, Marina 24 February 2011 (has links)
Made available in DSpace on 2016-07-18T17:53:08Z (GMT). No. of bitstreams: 1 DISSERTACAO.pdf: 506827 bytes, checksum: 85183faa6a63e1b561cacb568f6cf77e (MD5) Previous issue date: 2011-02-24 / The anti-inflammatory nonsteroidal compounds have extremely widespread use in the therapy of small animals, due to their anti-inflammatory and analgesic properties. However, the use of these drugs can produce changes in kidney function. The present study was conducted to assess kidney function in healthy dogs undergoing therapy with anti-inflammatory nonsteroidal compounds. Thirty mongrel dogs, adults, males and females, clinically healthy, were divided randomly into 5 groups (G) of six animals each receiving the following therapies: Gceto ketoprofen, a 2 mg/kg dose (VO), every 24 hours, during 10 days; Gnime nimesulide, 5 mg/Kg, VO, every 24 hours, during 10 days; Gmelo- meloxican, 0.2 mg/Kg on the first day, followed by 0.1 mg/Kg, VO, every 24 hours, 7 days; Geto etodolac, 15 mg/Kg, VO, every 24 hours, 7 days; Gcele- celecoxibe, 5 mg/Kg, VO, every 12 hours, for 20 days. The physical examination and renal function (urinalysis, urinary GGT, creatinine and sodium, serum urea, creatinine, potassium and sodium, and endogenous creatinine clearance) were assessed prior to the treatment, on the 5th and 10th days (T0, T5 and T10) into the treatment in all groups, and also on the 20th day (T20) into the treatment in Gcele. Few changes were observed in urinalysis parameters, only with significant increase in the presence of renal cells in the urine in T5, in the nimesulide group. There was a significant reduction in sodium elimination in the animals urine in the nimesulide group. The clearance values showed significant decrease in the celecoxibe group in T20, in relation to T5. The enzyme GGT urinary showed no variation among groups or moments. Values of sodium, potassium, urea and creatinine serum remained within normal ranges in all times, in the different groups. In conclusion, minimal changes of renal function occur 10 days after therapy on set with NSAIDS nimesulide, after 10 days with ketoprofen, on the 20th days of therapy with celecoxibe in health dogs. / Os anti-inflamatórios não-esteroidais têm uso extremamente difundido na clínica de pequenos animais, devido às suas propriedades analgésicas e anti-inflamatórias. Entretanto, o uso desses fármacos pode produzir alterações da função renal. O presente estudo teve como objetivo avaliar a função renal de cães saudáveis, submetidos à terapia com anti-inflamatórios não-esteroidais não seletivos, COX-2 preferenciais e COX-2 seletivos. Foram utilizados 30 cães, sem raça definida, adultos, machos e fêmeas, clinicamente sadios, divididos aleatoriamente em 5 grupos (G) de 6 animais cada, que receberam as seguintes terapias: Gceto cetoprofeno, na dose de 2 mg/Kg, por via oral (VO), a cada 24 horas, durante 10 dias; Gnime nimesulida, 5 mg/Kg, VO, a cada 24 horas, durante 10 dias; Gmelo - meloxican, 0,2 mg/Kg no primeiro dia, seguido por 0,1 mg/Kg, VO, a cada 24 horas, por 10 dias; Geto etodolaco, 15 mg/Kg, VO, a cada 24 horas, 10 dias; Gcele - celecoxibe, 5 mg/Kg, VO, a cada 12 horas, por 20 dias. O exame físico e a função renal (urinálise; GGT, creatinina e sódio urinários; uréia, creatinina, sódio e potássio séricos; e clearance endógeno de creatinina) foram avaliados antes, aos 5, 10 dias (T0, T5 e T10) de tratamento em todos os grupos, e também aos 20 dias (T20) de tratamento no Gcele. Poucas alterações foram observadas na urinálise, apenas com aumento significativo da presença de células renais na urina no T5 e T10 em relação ao T0, no grupo nimesulida. Houve redução significativa da eliminação de sódio na urina, nos animais do grupo nimesulida, no T5. Os valores de clearance foram os mais baixos no grupo Cetoprofeno no T10, e revelaram diminuição significativa no grupo Celecoxibe no T20, em relação ao T5. A enzima GGT urinária não apresentou variação entre grupos ou momentos. Valores de sódio, potássio, uréia e creatinina séricos mantiveram-se dentro da normalidade em todos os momentos nos diferentes grupos. Conclui-se que, em cães hígidos, alterações mínimas da função renal ocorrem aos cinco dias de terapia com o AINE nimesulida, aos dez dias com cetoprofeno, e aos vinte dias de terapia com celecoxibe.
80

Elucidating the anti-inflammatory actions of docosahexaenoic acid (DHA) in preventing ovarian cancer

Starkweather, Kara Nicole 01 September 2020 (has links)
Ovarian cancer is the fifth most lethal cancer in women (1) and the most lethal gynecological malignancy. In 2018, there were approximately 22,240 new diagnosed cases of ovarian cancer and 14,070 deaths in the United States alone (2). The lifetime risk for developing ovarian cancer in the United States is 1.3% or approximately 1 in 78 women. The five-year survival rate for women with ovarian cancer is a grim 47.6% (2) while the average five year survival rate for all cancers is about 68%. This dismal prognosis for ovarian cancer patients indicates the critical need for improved treatment options, efficient early detection methods and effective preventative measures for ovarian cancer (1). The objective of this study was to determine if DHA causes a reduction in cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) by blocking the activation of NF-κB regulated transcription in the ovary. DHA is a 22 carbon long-chain omega-3 polyunsaturated fatty acid that is biologically derived from Alpha-linolenic acid (ALA) found in flaxseed. COX-2 is an enzyme that catalyzes the conversion of arachidonic acid to prostaglandins. Prostaglandin E2 (PGE2) is a key regulator of inflammation which has been shown to be highly associated with ovarian cancer development and progression. Our laboratory studies ovarian cancer in the laying hen because it is the only known animal model to naturally develop ovarian cancer that both pathologically and histologically matches that of the human form of the disease. Dietary flaxseed is one of the richest vegetable sources of omega-3 polyunsaturated fatty acids. Our previous studies have shown that in laying hens, a long-term flaxseed supplemented diet reduces the incidence and severity of ovarian cancer and decreases COX-2 and PGE2. It was hypothesized that DHA, derived from ALA found in flaxseed, decreases inflammation in the ovaries by suppressing the activation of COX-2 and the production of PGE2 through inhibition of the NF-κB pathway. For this study, an NF-κB reporter plasmid was transfected into HEK293 cells. The reporter plasmid (“met-luc”) produces a secreted luciferase allowing sequential analysis of media from DHA and TNF-α treated cells to assess changes in NF-κB transcriptional activation. Tumor necrosis factor alpha (TNF-α)-induced activation of NF-κB was used as a positive control. NF-κB activation was also assessed by measuring its nuclear translocation and cytoplasmic accumulation through immunocytochemistry (ICC) and western blot analysis. In a parallel study, immortalized ovarian surface epithelial (IOSE) cells were challenged with the same treatments of DHA and TNF-α. In these cells, COX-2 mRNA was assessed through RT-qPCR and COX-2 protein expression was analyzed through ICC and western blot.Our results indicate that DHA acts in a cell specific manner to reduce inflammation associated with cancer. We have found that in HEK293 cells DHA reduces TNFα induced NF-κB reporter activity. In contrast, ALA does not affect NF-κB reporter activity. HEK293 cells treated with TNFα alone indicated a dose-dependent increasing trend in nuclear translocation of the NF-κB p65 subunit and a decreasing trend in cytoplasmic p65, suggesting potential increased pathway activation. ICC suggests DHA treatment causes increased cytoplasmic sequestration of the NF-κB p65 subunits indicating inhibition of TNFα induced NF-κB activation. Western blot data also indicates a decreasing trend in nuclear NFκB p65 when cells are pretreated with DHA and subsequently challenged with TNF. The IOSE cells, were the only cells out of the cell lines tested (BG1, HEYC2, TOV112D, SKOV3, HEK293) to express COX-2. In these IOSE cells, TNFα alone showed a dose-dependent increasing trend in COX-2 protein (analyzed through ICC and western blot) and mRNA levels (analyzed through RT-qPCR). ICC analysis revealed that DHA reduces TNF induced COX-2 protein expression. However, the western blot did not further support this observation. Only a slight non-significant reduction with DHA treatment was observed. In addition, both DHA and TNFα, while also not significant, seemed to increase mRNA levels of COX-2 compared to control. This slight decreasing trend in COX-2 protein expression and increase in mRNA, could indicate a possible post-transcriptional mechanism of regulation of COX-2 by DHA independent of NF-κB in the IOSE cells. These data suggest that DHA could act via distinct mechanisms in a cell specific manner to potentially reduce COX-2 and subsequently PGE2 levels. DHA can act at the transcriptional level by reducing the nuclear translocation of NF-κB and transcriptional activation of NF-κB target genes such as COX-2 in some cell types. DHA also has the potential to work via a post-transcriptional mechanism to inhibit COX-2 and in turn reduce PGE2 levels. Both mechanisms ultimately have the potential to decrease the inflammation associated with ovarian cancer. This study describes the anti-inflammatory action of dietary flaxseed consumption, making flaxseed supplementation a promising preventive measure for reducing the risk of ovarian carcinogenesis.

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