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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.
281

Epstein-Barr virus latency in transplant patients and health carriers /

Zou, JieZhi. January 2005 (has links)
Lic.-avh. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 3 uppsatser.
282

Carcinoma de células escamosas oral: relevância do Papiloma vírus humano (HPV) e do vírus Epstein-Barr (EBV) na expressão de proteinas p16INK4a, E-caderina, COX-2, MLH1, p53 e MYC. / Oral squamous cell carcinoma: Relevance of Human Papillomavirus (HPV) and Epstein-Barr virus (EBV) on the expression of the proteins p16INK4a, E-cadherin, COX-2, MLH1, p53 e MYC.

Lima, Marcos Antonio Pereira de January 2013 (has links)
LIMA, Marcos Antonio Pereira de. Carcinoma de células escamosas oral: relevância do Papiloma vírus humano (HPV) e do vírus Epstein-Barr (EBV) na expressão de proteinas p16INK4a, E-caderina, COX-2, MLH1, p53 e MYC. 2013. 180 f. : Tese (doudorado) - Universidade Federal do Ceará, Programa de Pós-Graduação em Biotecnologia, Rede Nordestes de Biotecnologia -Renorbio, Fortaleza-CE, 2013. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-05-27T13:30:28Z No. of bitstreams: 1 2013_tese_maplima.pdf: 16584856 bytes, checksum: 9b25880d41a42f87ebcd6222528b072e (MD5) / Approved for entry into archive by demia Maia (demiamlm@gmail.com) on 2016-05-27T13:30:59Z (GMT) No. of bitstreams: 1 2013_tese_maplima.pdf: 16584856 bytes, checksum: 9b25880d41a42f87ebcd6222528b072e (MD5) / Made available in DSpace on 2016-05-27T13:30:59Z (GMT). No. of bitstreams: 1 2013_tese_maplima.pdf: 16584856 bytes, checksum: 9b25880d41a42f87ebcd6222528b072e (MD5) Previous issue date: 2013 / The oral cancer represents a serious world public health problem. The oral squamous cell carcinomas (OSCC) account for up to 94% of the tumors of this anatomic site. The molecular mechanisms involved in the genesis and progression are still not well elucidated. Some evidences have suggested the involvement of viruses in this process. Also, these tumors still lack of reliable markers to determine the aggressiveness profile. In this context, the aim of the present study was to evaluate the expression of the proteins p53, E-cadherin, COX-2, p16, MLH1 and MYC in a serie of OSCC, including the cytoplasmic staining eventually observed for the latter three proteins, confronting the results between them and with demographic and clinico-pathological features. Besides evaluating the prevalence of Human Papillomavirus (HPV) and Epstein-Barr virus (EBV) in the sample and compare them with the expression of the referred proteins. Materials and Methods – One hundred formalin-fixed paraffin-embedded OSCC specimens were submitted to immunohistochemistry for detection of the referred proteins, and to in situ hybridization for HPV and EBV detection. Results – OSCC was associated with a concomitant lack of expression of p16 and MLH1 (p=0.029) and coexpression of p53 and COX-2 (p=0.045). Additionally, COX-2 and nuclear MYC were found to be related to exclusively cytoplasmic staining of MLH1 (p=0.060 and p=0.018, respectively). The combination analyses of the markers revealed five main groups of altered protein expression, which were mostly of the more aggressive tumors, mainly the MLH1(-)/COX-2(+)/p16(-) group. The cases with cytoplasmic staining for p16, MLH1 and/or MYC were more frequent in advanced tumors (p=0.009) and in those with lymph node metastasis (p=0.001). Thirty-one cases showed staining for HPV in tumor tissue. The EBV was not detected in any case investigated, neither in the tumor tissue nor in the non-neoplastic epithelium. The HPV(+) group demonstrated high positivity for nuclear p16 (p=0,029) and cytoplasmic MYC (p=0,039), and an increase of the lack of MLH1 nuclear expression (p=0,031). There was also a trend related to the increase of the COX-2 positivity in the HPV(+) group (p=0,084). Conclusions – The significance between p16 and MLH1 suggests that the lack of this member of mismatch repair system also favors the occurrence of mutations in the p16 gene, culminating in inactivation of this tumor suppressor. The associations of COX-2 and MYC with cytoplasmic MLH1 suggest a blocking mechanism for the entry of MLH1 into the nucleus. The combined analyses of the proteins investigated, as well as the cytoplasmic staining of p16, MLH1 and MYC, may be useful in the evaluation of the aggressive profile and probably prognosis of OSCC. Regarding the viruses, our findings suggest that the HPV is involved in an important portion of OSCC cases and that may promote the expression of the nuclear p16, cytoplasmic MYC and COX-2, and suppress the nuclear expression of MLH1. About EBV, it was not detected the EBV-encoded small RNAs (EBERs) in the sample. / O câncer oral representa um sério problema de saúde pública mundial. Entre os tumores deste sítio anatômico, os carcinomas de células escamosas orais (CCEO) respondem por até 94% do total. Os mecanismos moleculares envolvidos na gênese e desenvolvimento tumoral ainda não estão completamente elucidados. Algumas evidências têm sugerido a participação viral neste processo. Além disso, estes tumores ainda carecem de marcadores confiáveis para determinar o perfil de agressividade. Neste contexto, o presente estudo teve como objetivo avaliar a expressão das proteínas p53, E-caderina, COX-2, p16, MLH1 e MYC numa série de CCEO, considerando também a marcação citoplasmática eventualmente observada para as últimas três proteínas, confrontando os resultados entre elas e com as características demográficas e clínico-patológicas. Além de avaliar a prevalência do Papilomavírus Humano (HPV) e do Vírus Epstein-Barr (EBV) na amostra e compará-las com a expressão das referidas proteínas. Materiais e Métodos – Cem espécimes de CCEO, fixados em formalina e incluídos em blocos de parafina, foram submetidos à imunohistoquímica para a detecção das referidas proteínas e à hibridação in situ para detecaçõ de HPV e EBV. Resultados – Foi observada associação referente à perda de expressão concomitante de p16 e MLH1 (p=0,029) e na coexpressão de p53 e COX-2 (p=0,045). Ademais, foi verificado que a COX-2 e o MYC nuclear estavam relacionados com a marcação citoplasmática de MLH1 (p=0,060 e p=0,018; respectivamente). A análise combinada dos marcadores revelou cinco grupos principais de expressão alterada que eram constituídos, em sua maioria, de tumores mais agressivos, principalmente o grupo MLH1(-)/COX-2(+)/p16(-). Os casos com marcação citoplasmática para p16, MLH1 e/ou MYC foram mais frequentes em tumores avançados (p=0,009) e naqueles com metástases em linfonodos (p=0,001). Trinta e um casos demonstraram marcação para HPV em tecido tumoral. O EBV não foi detectado em nenhum dos casos investigados, nem no tecido tumoral nem no epitélio não neoplásico. O grupo HPV(+) exibiu elevada positividade para o p16 nuclear (p=0,029) e MYC cytoplasmático (p=0,039), também uma maior perda de expressão nuclear de MLH1 (p=0,031). Houve ainda uma tendência referente ao aumento da positividade de COX-2 no grupo infectado (p=0,084). Conclusões – As significâncias verificadas entre p16 e MLH1 sugerem que a ausência do membro do sistema de reparo de encaixe (MMR) também favoreça a ocorrência de mutações no gene p16, culminando na inativação deste supressor tumoral. As associações de COX-2 e MYC com o MLH1 de expressão citoplasmática suscitam um mecanismo de bloqueio de entrada de MLH1 no núcleo. A análise combinada das proteínas, bem como, a marcação citoplasmática de p16, MLH1 e MYC, podem representar indicadores úteis na avaliação do perfil de agressividade e, provavelmente, de prognóstico em CCEO. Acerca dos vírus, nossos achados sugerem que o HPV esteja envolvido em uma importante parcela de casos de CCEO e que possa promover a expressão de p16 nuclear, MYC citoplasmático e COX-2, e suprimir a expressão nuclear de MLH1. Quanto ao EBV, não foram detectados EBERs (EBV-encoded small RNAs) na amostra.
283

Multiple sclerosis in Västerbotten county, northern Sweden

Sundström, Peter January 2003 (has links)
One out of several distinguishing features of multiple sclerosis (MS) is the epidemiological variation of geographic distribution. Population-based studies on the prevalence and incidence of MS in Sweden have previously been performed only in Göteborg. Another feature of MS is the clinical variation between individuals. To a large extent data on the clinical characteristics of MS come from studies on cases frequenting MS clinics and therefore, may be biased. Also rare are population-based studies of the consequences of MS-related incapacity on socio­economic factors. As for MS aetiology, both environment and genes are involved. Human herpesviruses are often the main suspected environmental aetiological agents. Our aim was to estimate the prevalence of MS in Västerbotten County for 1 January 1990, the incidence during a 10-year period 1988-97, and the prevalence 31 December 1997; and also to present detailed clinical data including onset symptoms and the disability distribution for the latter two MS populations. Furthermore, we wanted to estimate the prevalence of sick leave, professional assistance, and housing; and also, to study the risk factors for sick leave. In order to investigate the association between MS and human herpesviruses, samples were identified in two regional population-based serumbank registers. This linkage identified samples collected from before MS-onset in 73 MS cases and after MS onset in 161 cases The prevalence and incidence populations were identified through multiple sources. Diagnostic ascertainment, the reliability of clinical data, and additional information were assured from a questionnaire with follow-up interview and neurological examination. The onset adjusted crude prevalence of MS was 125/100,000 (95% CI: 112-140) in January 1990, and 154/100,000 (95% Cl: 139-170) in December 1997. The increase was mainly attributable to a higher incidence than mortality. The crude incidence rate 1988-97 was 5.2/100,000 (95% CI: 4.4-6.2). The disability distribution in the 1997 prevalence population in Västerbotten was compared to the disability distribution in a Canadian MS population, which has been used for publications on the natural history of MS. One difference from the Canadian studies appears to be the better recognition of cases with more benign disease. Nevertheless almost half of prevalent MS cases aged 18-64 years were fully sick-listed, and one-fourth of all prevalent cases received professional assistance. High disability level was the strongest predictor for sick leave. All MS cases showed signs of past Epstein-Barr virus (EBV) infection. High activity to EBV (EBNA-1 but not VCA) and human herpesvirus 6 (HHV-6) significantly (borderline significance for HHV-6) increased the risk to develop MS. These estimates show that Västerbotten County is a high risk area for MS. Both incidence and prevalence were significantly higher when compared to estimates from Göteborg. The comparison with the Canadian MS population shows that MS might be a slightly more benign disease than previously recognized. Still, the consequences of MS regarding socio-economic aspects are considerable. We suggest that EBV is a prerequisite for the development of MS. Individuals that will develop MS exhibit an altered immune response against the EBV virus characterised by high activities to EBNA-1 in the absence of high VCA activities, this being most pronounced in the five-year period preceding MS onset. A pathogenetic role is suggested for EBV and remains possible also for HHV-6. / digitalisering@umu
284

Control of chronic Epstein-Barr virus infection : consequences of altered B lymphocyte activation / Conséquences de l'altération de l'activation des lymphocytes B sur le contrôle de l'infection chronique par EBV

Sanosyan, Armen 15 December 2016 (has links)
Le virus d'Epstein-Barr (EBV), est un gamma herpes virus exclusivement humain qui infecte près de 95% de la population adulte. EBV établit un cycle de latence dans les cellules B mémoires et les cellules épithéliales. EBV entre périodiquement dans une réplication lytique avec sécrétion des virions dans la salive. L’infection EBV est associée à l’apparition de lymphomes, de cancers et de maladies auto-immunes. Les conditions favorisant le développement de ces pathologies restent mal connues mais l’immunodépression et potentiellement l’activation des lymphocytes B nécessaire à la réplication d’EBV jouent un rôle clé.Nous avons examiné l’association entre activation des cellules B dans le compartiment systémique et le contrôle sur le réservoir de l’EBV. Deux situations cliniques d’activation chronique des cellules B ont été explorées ; le syndrome de Gougerot-Sjögren et la mastite subclinique dans le contexte de l’infection par le VIH.Dans ce travail de thèse, nous avons tout d’abord développé une PCR en temps réel pour la quantification de l'ADN de EBV ciblant la région répétée BamHI-W du génome. Le travail de validation de la technique a permis d’évaluer précisément le gain de sensibilité comparativement à une qPCR LMP2 (cible unique). L’impact des variations de répétition de la séquence BamHI-W suivant les souches et isolats EBV a également été analyse.Dans un deuxième travail, nous avons montré que, la mastite subclinique était fréquente au cours de l’allaitement et qu’elle était un facteur indépendant associé à une augmentation de l'excrétion EBV par le lait maternel. Cette sécrétion est associée localement à l’inflammation et à l’excrétion du VIH ce qui témoigne de phénomène de synergie entre les deux virus. Nous avons également démontré que l'ADN EBV dans le lait maternel peut être résistant à la DNase et que le virus était est probablement encapsidé dans le lait, donc potentiellement infectieux.Enfin, bénéficiant d’un accès aux prélèvements de la cohorte ASSESS nous avons recherché de possible anomalie du contrôle de l’infection EBV dans le compartiment sanguin au cours du syndrome de Gougerot-Sjögren primaire dans lequel les lésions glandulaires salivaires et lacrymales sont associées à la présence d’EBV. Nous avons démontré que le réservoir EBV et la réplication EBV dans le compartiment systémique sont bien contrôlées au cours du syndrome de Gougerot-Sjögren primaire. La réponse anticorps contre l’antigène précoce d’EBV (EA) n'était pas associée à une augmentation de l'ADN de EBV.Ce travail de thèse, souligne le lien entre l'activation des lymphocytes B, l'inflammation chronique et le contrôle sur le réservoir d’EBV. Dans la glande mammaire le contrôle de l’infection EBV est perturbé en cas de mastite subclinique. Au contraire dans le syndrome de Gougerot-Sjögren l’infection reste bien contrôlée dans le compartiment sanguin malgré l’activation des lymphocytes B et la présence renforcée du virus dans les lésions glandulaires. / TEpstein-Barr virus (EBV), an ubiquitous human gammaherpesvirus affects 95% of adult human population and establishes a lifelong latency in memory B cells periodically entering into lytic replication with further propagation in oropharyngeal epithelia and shedding through saliva. Latent EBV infection is associated with lymphomas, carcinomas and autoimmune diseases. Although the conditions favoring the development of these pathologies are not completely understood, the immunosuppression and B cell activations play an important role in EBV-associated diseases.We examined the control over the EBV reservoir in a diseases associated with B cell activation. Two clinical situations associated with altered B cell activation were explored: primary Sjogren’s syndrome and subclinical mastitis in HIV-infected mothers.Primarily, we developed an in-house real-time PCR for EBV DNA quantification targeting the repetitive BamHI-W region of EBV DNA. The validation analyses enabled to evaluate the gain in sensitivity of the BamHI-W test relative to single repeat LMP2 qPCR. The impact of the variations in BamHI-W reiteration on EBV DNA quantification was further assessed on different EBV strains and clinical samples.In a second study, we showed that subclinical mastitis was common during breastfeeding, and it was an independent factor associated with increased EBV breast milk shedding. This secretion was associated with local inflammation and HIV shedding, reflecting synergy between the two viruses. We have also demonstrated that breast milk EBV DNA may be resistant to DNase, and the virus was probably encapsidated in the breast milk and thus potentially infectious.Finally, with an access to ASSESS cohort we looked for possible abnormal control over EBV infection in the blood compartment in primary Sjögren's syndrome, where salivary and lacrimal gland lesions were shown to be associated with the local activation of EBV. We have demonstrated that in primary Sjogren's syndrome EBV reservoir and replication in the systemic compartment are well controlled. The antibody response against EBV early antigen (EA) was not associated with increased DNA EBV.This thesis points out the link between the activation of B cells, chronic inflammation and control over the reservoir of EBV. In the mammary gland disturbed control of EBV infection is linked with subclinical mastitis. In contrast, in primary Sjogren’s syndrome EBV infection remains well controlled in the blood compartment despite the activation of B cells and the increased presence of the virus in glandular lesions.
285

Genomic and Transcriptomic Investigation of Endemic Burkitt Lymphoma and Epstein Barr Virus

Kaymaz, Yasin 31 July 2017 (has links)
Endemic Burkitt lymphoma (eBL) is the most common pediatric cancer in malaria-endemic equatorial Africa and nearly always contains Epstein-Barr virus (EBV), unlike sporadic Burkitt Lymphoma (sBL) that occurs with a lower incidence in developed countries. Despite this increased burden the study of eBL has lagged. Additionally, while EBV was isolated from an African Burkitt lymphoma tumor 50 years ago, however, the impact of viral variation in oncogenesis is just beginning to be fully explored. In my thesis research, I focused on investigating molecular genetics of the endemic form of this lymphoma with a particular emphasis on the role of the virus and its variation in pathogenesis using novel sequencing and bioinformatic strategies. First, we sought to understand pathogenesis by investigating transcriptomes using RNA sequencing (RNAseq) from 30 primary eBL tumors and compared to sBL tumors. BL tumor samples were prospectively obtained from 2009 until 2012 in Kenya. Within eBL tumors, minimal expression differences were found based on anatomical presentation site, in-hospital survival rates, and EBV genome type; suggesting that eBL tumors are homogeneous without marked subtypes. The outstanding difference detected using surrogate variable analysis was the significantly decreased expression of key genes in the immunoproteasome complex in eBL tumors carrying type 2 EBV compared to type 1 EBV. Secondly, in comparison to previously published pediatric sBL specimens, the majority of the expression and pathway differences were related to the PTEN/PI3K/mTOR signaling pathway and was correlated most strongly with EBV status rather than the geographic designation. Moreover, the common mutations were observed significantly less frequently in eBL tumors harboring EBV type 1, with mutation frequencies similar between tumors with EBV type 2 and without EBV. In addition to the previously reported genes, we identified a set of new genes mutated in BL. Overall, these suggested that EBV, particularly EBV type 1, supports BL oncogenesis alleviating the need for particular driver mutations in the human genome. Second, we sought to comprehensively define sequence variations of EBV across the viral genome in eBL tumor cells and normal infections, and correlate variations with clinical phenotypes and disease risk. We investigated the whole genome sequence of EBV from primary tumors (N=41) and plasma from eBL patients (N=21) as well as EBV in the blood of healthy children (N=29) within the same malaria endemic region. We conducted a genome wide association analysis study with viral genomes of healthy kids and BL kids. Furthermore, we found that the frequencies of EBV types among healthy kids were at equal levels while they were skewed in favor of type 1 (70%) among eBL kids. To pinpoint the fundamental divergence between viral genome subtypes, type 1 and type 2, we constructed phylogenetic trees comparing to all public EBV genomes. The pattern of variation defined the substructures correlated with the subtypes. This investigation not only deciphers the puzzling pathogenic differences between subtypes but also helps to understand how these two EBV types persist in the population at the same time. Overall, this research provides insight into the molecular underpinning of eBL and the role of EBV. It further provides the groundwork and means to unravel the complexity of EBV population structure and provide insight into the viral variation that may influence oncogenesis and outcomes in eBL and other EBV-associated diseases. In addition, genomic and mutational analyses of Burkitt lymphoma tumors identify key differences based on viral content and clinical outcomes suggesting new avenues for the development of prognostic molecular biomarkers and therapeutic interventions.
286

Caractérisation structurale et fonctionnelle des interactions impliquant TFIIH et les domaines de transactivation viraux

R. Chabot, Philippe 02 1900 (has links)
Le facteur de transcription IIH (TFIIH) joue un rôle crucial dans la transcription et dans la réparation de l’ADN. La sous-unité Tfb1/p62 (levure et humain) de TFIIH interagit avec de nombreux facteurs de transcription (p53, NFκB, TFIIEα) et de réparation (Rad2/XPG and Rad4/XPC) (1). La majorité des interactions avec Tfb1/p62 requiert le domaine d’homologie à la Pleckstrin (PH) localisé dans la région N-terminal de la protéine (2, 3). Ce domaine PH forme des complexes avec des domaines de transactivation acide provenant de protéines cibles impliquées dans la transcription et la réparation de l’ADN. De récentes études ont montré que Tfb1/p62 est une cible pour les protéines virales telles que la protéine VP16 du virus de l’herpès simplex (HSV) de type 1, la protéine E1 du virus du papillome humain (VPH) et la protéine EBNA-2 du virus Epstein-Barr (EBV) (4, 5). Ces protéines virales interagissent avec la sous-unité Tfb1/p62 par un domaine de transactivation acide suggérant une interaction similaire à ce qui est observé chez les facteurs de transcription humains comme p53. Ce mémoire présente une caractérisation structurelle et fonctionnelle du complexe formé par la protéine virale EBNA2 et la protéine humaine Tfb1/p62. L’analyse est faite en utilisant le titrage calorimétrique isotherme (ITC), la résonance magnétique nucléaire (RMN) et une expérience de transactivation chez la levure. Cette étude amène une plus grande compréhension des protéines impliquées dans les maladies comme le lymphome de Burkitt et le lymphome de Hodgkin qui sont souvent associées à l’infection à l’EBV (revue dans (6)) et caractérise une cible potentielle pour un antiviral. / The general transcription factor IIH (TFIIH) plays crucial roles in both transcription and DNA repair. Tfb1/p62 (yeast and human), one of the ten/eleven subunits of TFIIH, has been shown to interact with several important transcription (p53, NFκB, TFIIEα) and repair factors (Rad2/XPG and Rad4/XPC) (1). Most of the interactions with Tfb1/p62 require the Pleckstrin homology (PH) domain located at the amino-terminal end of the protein (2, 3). This PH domain in particular forms complexes with highly acidic domains from target proteins involved in both transcriptional activation and DNA repair. Recent studies has shown that the Tfb1/p62 subunit of TFIIH is also targeted by a number of viral proteins including the Herpes Simplex virus (HSV) protein VP16, the Human papillomavirus (HPV) protein HPV E1 and the Epstein-Barr virus (EBV) protein EBNA-2 (4, 5). These viral proteins interact with the Tfb1/p62 subunit via acidic domain which suggests that they are forming similar interactions as the one observed with human transcription and repair factors. This thesis provides a structural and functional characterization of the complex formed by the viral proteins EBNA2 and the human protein Tfb1/p62 subunit of TFIIH. The analysis is done using isothermal titration calorimetry (ITC), nuclear magnetic resonance (NMR) spectroscopy and a yeast activation assay. This study brings a greater understanding of proteins implicated in diseases such as the Burkitt’s lymphoma directly linked to an EBV infection (review in (6)) and shows a viable target for antiviral drug.
287

Parent involvement in early childhood development in Kwazulu Natal

Bridgemohan, Radhika Rani 11 1900 (has links)
This study on parent involvement in Early Childhood Development in KwaZulu Natal investigates the experiences of educators and parents of the different types of parent and community involvement as set out in the Epstein typology. In order to investigate this phenomenon a thorough background of the theory and practice of the Epstein model has been provided. In addition the work of other researchers that support the Epstein typology of parent involvement forms an integral part of the discussions. As parent involvement is the key focus of the study, parent involvement in education before and after 1994 are discussed. In this regard relevant educational policy and legislation that are designed to increase the role of parents and the community in Early Childhood Development are highlighted. Parents' role in the provision of Early Childhood Development is explored. The provision of Early Childhood Development in KwaZulu Natal, which provides a backdrop for the investigation, is explained. In addition contextual factors that influence parent involvement in KwaZulu Natal are provided. The research methodology and the research design used in this study are described in detail. By means of a qualitative approach the experiences of a small sample of educators and parents in Early Childhood Development are explored using the six types of parent involvement that include parenting, communicating, volunteering, learning at home and collaborating with the community as set out in Epstein's comprehensive model. The experiences of educators and parents of Grade R learners of the six types of involvement have been included. Although all schools engage in some form of parent involvement, it is evident that not all schools involve parents in all types of parent involvement to the same extent. The study concludes with recommendations for developing strategies to involve parents more effectively in Early Childhood Development in KwaZulu Natal. / Educational Studies / D. Ed. (Comparative Education)
288

Essays on redistributive policies and household finance with heterogeneous agents

Hubar, Sylwia Patrycja January 2013 (has links)
The overall objective of the thesis is to investigate needs and incentives of all income/wealth groups in order to explore ways and means to remedy the excessive economic inequality. A closer examination of individual decisions across richer and poorer households allows us to recognize conflicts of wants, needs and values and subsequently to draw recommendations for future policies. The first chapter examines households' preferences over the redistribution of wealth resources. The preferences of voting households are restricted by agents' present and future resource constraints. The wealth resources vary over the business cycle, which affects the grounds for speculations of voting households. We augment the standard Real-Business-Cycle (RBC) model by the majority voting on lump-sum redistribution employing a balanced government budget. Our findings indicate that for the usual elasticity of labor supply both transfers' level and share of output are procyclical, with the procyclicality increasing in the discrepancy between richer and poorer households. In the second chapter we analytically demonstrate that all economic agents face subsistence costs that hinder economic and financial decisions of the poor. We find that the standard two-asset portfolio-selection model with a time-invariant subsistence component in the common-across agents Stone-Geary utility function is capable of explaining qualitatively and quantitatively three empirical regularities: (i) increasing saving rates in wealth, (ii) rising risky portfolio shares with wealth, (iii) more volatile consumption growth of the richer. On the contrary, "keeping-up-with-the-Joneses" utility with a time-varying weighted mean consumption produces identical saving rates and portfolio asset shares across richer and poorer agents, failing to match the micro data. Finally, in the third chapter we use Epstein-Zin-Weil recursive preferences altered to include subsistence costs, as this form of utility function enables trade-off between stability and safety. We pursue an analytical investigation of a more complex multi-asset portfolio-choice model with perfectly insurable labor risk and no liquidity constraints and find further support of the data evidence. If households' total resources are anticipated to increase over time, poorer agents can afford to gradually escape subsistence concerns by choosing lower saving rates and accepting only minor portfolio risks as their consumption hovers close to the subsistence needs. The calibration part of the model economy shows that analytical results can quantitatively reconcile the data, too.
289

Autonomia e campo ampliado: Peter Eisenman, Rosalind Krauss e The Institute for Architecture and Urban Studies (1964-1984) / Autonomy and extended field: Peter Eisenman, Rosalind Krauss and The Institute for Architecture and Urban Studies (1964-1984)

Schiavo, Bruno 24 June 2016 (has links)
A atualidade é marcada pela descoberta contínua dos interstícios disciplinares como catalisadores de toda sorte de práticas; expressões como \"Campo ampliado\" e \"Complexo artearquitetura\" são chamadas para refletir como tais arranjos acontecem especialmente na confluência entre a arquitetura e as artes. A pesquisa busca localizar, na passagem dos anos 1960 aos 1980, um debate que solicitou desses campos a reconfiguração de seus instrumentos de análise, de crítica, de abordagem à forma, e mesmo uma nova inscrição de seus significados e abrangências: o cruzamento das trajetórias intelectuais da teórica e crítica de arte Rosalind Krauss e do arquiteto e teórico Peter Eisenman no The Institute for Architecture and Urban Studies - IAUS, sediado em Nova York de 1967 a 1985. O instituto colocou-se como núcleo da pesquisa interdisciplinar de seu tempo ao promover cursos, conferências, mostras, publicações, e ao legar dois periódicos especializados que encaminhariam as agendas da arquitetura e das artes nas décadas seguintes, respectivamente, Oppositions: A Jornal for Ideas and Criticism in Architecture (1973-1984) e October (1976 até o presente). O estudo passa pelas proposições questionadoras da primazia do suporte artístico no minimalismo até a cristalização dessas dinâmicas no ensaio \"A escultura no campo ampliado\", de Krauss; e pela verificação, no início dos anos 1960, da necessidade pela reelaboração das questões de relevância para a arquitetura e para o urbanismo, que levariam ao sentido autocrítico investido na noção de autonomia disciplinar, e ao sentido autorreferencial da autonomia da forma arquitetônica, como engendrado por Eisenman. As experiências que assumiriam o espaço físico como constitutivo do trabalho artístico contrastam em diversos níveis com a modalidade conceitual perscrutada por essa arquitetura. Alguns dos pontos de apoio compartilhados pelos movimentos teóricos em questão são as noções de objeto, ambiente, formalismo, linguagem, modernismo e pós-modernismo. Mantendo entre si relações de complementaridade, de reciprocidade, de contradição, o empréstimo a tais categorias entre disciplinas é compreendido em vista de um segundo plano institucional. / The current situation is marked by the continuous discovery of the disciplinary interstices as Catalysts of all kinds of practices; Expressions such as \"Expanded Field\" and \"Complexo artearquitetura\" Are called to reflect how such arrangements Confluence between architecture and the arts. The research seeks to locate, over the years 1960 to the 1980s, a debate that called for these areas to reconfigure their Instruments of analysis, criticism, approach to form, and even a new inscription of Their meanings and scope: the crossing of the intellectual trajectories of the theoretical and critical Rosalind Krauss and the architect and theorist Peter Eisenman at The Institute for Architecture and Urban Studies - IAUS, headquartered in New York from 1967 to 1985. The Has placed himself as the core of interdisciplinary research of his time while promoting courses, Conferences, exhibitions, publications, and by bequeathing two specialized journals Would move the agendas of architecture and the arts in the following decades, Respectively, Oppositions: The Journal for Ideas and Criticism in Architecture (1973-1984) and October (1976 to present). The study goes through the questioning propositions of primacy Of artistic support in minimalism until the crystallization of these dynamics in the essay \"The sculpture In the extended field \", by Krauss; And the verification, in the early 1960s, of the need By the re-elaboration of issues of relevance to architecture and urbanism, which Would lead to the self-critical sense invested in the notion of disciplinary autonomy, and to the sense Self-referential autonomy of the architectural form, as engendered by Eisenman. At Experiences that would take physical space as constitutive of artistic work contrast In several levels with the conceptual modality examined by this architecture. Some of Points of support shared by the theoretical movements in question are the notions of Object, environment, formalism, language, modernism and postmodernism. Keeping each other Relations of complementarity, of reciprocity, of contradiction, the loan to such Between disciplines is understood in view of a second institutional plan.
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Associations Between Rheumatoid Arthritis and Malignant Lymphomas

Baecklund, Eva January 2005 (has links)
<p>Patients with rheumatoid arthritis (RA) are at increased risk of developing malignant lymphoma, although details about this association remain unclear. The aims of this thesis were to investigate risk factors for lymphoma in patients with RA and to characterize these lymphomas regarding subtype, presence of Epstein-Barr virus (EBV), clinical manifestations and prognosis. </p><p>The Swedish hospital discharge register and the cancer register were used to identify RA patients with lymphoma. Two case-control studies were performed, one smaller including RA patients with lymphoma hospitalised in Uppsala health care region 1964-1983 (n=41) and one larger study of hospitalised RA patients with lymphoma in Sweden 1964-1995 (n=378). RA patients from the same cohorts, but without lymphoma, were matched as controls. Medical records for cases and controls were scrutinized for exposure information. The lymphoma tissues were reclassified according to the WHO classification, and presence of EBV was analysed by EBER in situ hybridisation.</p><p>The most important risk factor for lymphoma development was high RA disease activity. No association was determined between treatment with traditional disease modifying drugs, non-steroidal anti-inflammatory drugs, aspirin, peroral and intra-articular corticosteroids and lymphoma risk. Diffuse large B-cell lymphoma (DLBCL) was more frequent in RA patients than in lymphoma patients in the general population and displayed stronger association with RA disease activity than other lymphoma subtypes. RA patients with DLBCL had increased extranodal involvement and more advanced lymphoma stage at presentation than DLBCL patients in general, and the prognosis was poor. </p><p>A further subdivision of DLBCL into germinal centre (GC) and non-GC subtypes by the expression patterns of CD10, bcl-6 and IRF-4 showed a predominance of the non-GC subtype. This suggested peripheral activated B-cells as the cells of origin in these lymphomas. </p><p>The presence of EBV was low in lymphomas in RA patients (12%). </p>

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