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The intensity of light produced from synchrotrons enables X-ray imaging down to the micron and submicron scale. This high degree of resolution is necessary to study metals in hydrated biological samples, where trace (metal) elements are found in the lowest concentration. Water within these aqueous samples will undergo radiolysis and produce various reactive oxygen species, which degrades the quality of information gathered from the sample during X-ray imaging. Studies have shown that the best way to counter the effects of radiolysis and preserve samples in their metabolic state during X-ray imaging is to keep them cryogenically frozen. We have developed affordable cryostats and novel protocol to not only improve cryo-imaging at current third-generation synchrotrons, but also enable cryo-imaging at existing synchrotrons that have limited accessibility. This dissertation will provide a detailed description of the tasks that were accomplished to contribute to the development cryo-imaging. The first task was the fabrication of a portable cryostage. The cryostage's discreet profile and unique design successfully enabled it to be effortlessly adapted into three beamlines across two different DOE facilities and facilitate multiple imaging modalities, i.e., correlative imaging. With the next task, we explored adding an ice frame about the stage to help reduce the accumulation of frost on the surface of a frozen sample that was explored. The addition of the ice frame significantly improved the imaging of frozen samples, nearly doubling the overall image clarity in comparison to when it was absent. The final task saw the application of a cryostream, in place of a cryostage, to provide a cooled convective flux across the sample for 2D and 3D visualization for cryo X-ray imaging. / Doctor of Philosophy / Synchrotrons are light producing particle accelerators that enable X-ray imaging down to the micron and submicron scale. This high degree of resolution is necessary to study metals in hydrated biological samples, where trace elements are found in low concentrations. The X-ray beam from the synchrotron will force any water within these aqueous samples to undergo radiation induced water decomposition, i.e., radiolysis, and produce hydroxyl radicals that will degrade the quality of information gathered from the sample during X-ray imaging. Early studies have shown that the best counter to the effects of radiolysis, while also preserving samples in their metabolic state during X-ray imaging, is to keep them cryogenically frozen. We have developed affordable cryostats and novel protocols to not only improve cryo-imaging at current third-generation synchrotrons, but also enable cryo-imaging at existing synchrotrons that have limited accessibility. This dissertation will describe, in detail, three tasks that were accomplished. The first task was to the fabrication of a portable cryostage. The cryostage unique design successfully enabled it to be used within different beamlines and for multiple imaging perspectives. With the next task, an ice frame to help reduce the accumulation of frost on the surface of a frozen sample being explored. The ice frame was shown to significantly improve the imaging of frozen samples. The final task saw the application of a cryostream, a jet stream of cold nitrogen gas, to enable an alternative approach for 2D and 3D visualization for cryo X-ray imaging.

No / Set in the context of efforts to utilise chemicals as weapons of war, that have their origins in collaborative efforts between the UK and the US during World War I, this chapter examines the origins, the evolution, and the hostile misuse of chemical anti-crop agents and defoliants. Out of efforts between the two countries that endured throughout World War II, military interest in chemical anti-crop agents and defoliants emerged in-part as a consequence of a close association between civilian chemistry and military chemistry. It is shown by way of insights provided from official sources from the United Kingdom (UK) National Archive that UK use of such agents in Malaya resulted in the emergence of new techniques concerning the large-scale use of chemical anti-plant agents, as well as methods for their widespread dissemination. It is argued here that the above can be seen as a prelude to subsequent use in Vietnam, the latter having implications of relevance to human health and for the environment. It is shown that the role of science policy experts in bringing influence to bear on policy-makers during the latter part of the Vietnam War was significant in bringing about change in policy and an end to use in Vietnam. Also of significance is the issue of chemical weapons in the context of efforts to codify the norm of non-use under the Geneva Protocol, under the Chemical Weapons Convention (CWC), and under a range of related prohibition regimes. This chapter considers the implications of the scientific and technological developments in phytobiology of relevance, in particular, to auxins (work on endogenous growth regulators—auxins—would lead to the discovery of “the first systemic or hormone herbicides”). The findings are drawn together in a concluding section at the end of this chapter.

Made available in DSpace on 2015-02-04T21:42:06Z (GMT). No. of bitstreams: 1 Maria Heloiza.pdf: 504743 bytes, checksum: 4fde6c28fc11e48070d8c696d00b78e9 (MD5) Previous issue date: 2009-10-23 / Este estudo epidemiológico foi realizado com o objetivo de definir a soroprevalência das hepatites virais B e C em escolares que freqüentavam regularmente as escolas municipais de Ensino Fundamental no município de Santos, no período de novembro de 2008 a março de 2009,. Foram analisadas 98 amostras de sangue de escolares com idade entre 4 e 14 anos, através da técnica de ELISA, para detecção da presença de anticorpos anti-HVC, anti-HBc anti-HBs e HBsAg, Setenta e duas amostras foram positivas para a detecção do anti-HBs, mostrando uma eficácia na vacinação contra hepatite B de 75%. Em duas crianças foi detectada a presença do HVC, demonstrando uma prevalência de 2,8%. A pesquisa do anti-HBc foi positiva em duas crianças (prevalência de 2,8%) e o HBs-Ag foi detectado em uma criança (prevalência de 1,3%).

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-05-12T21:06:34Z No. of bitstreams: 1 DenilsonVieira.pdf: 1857476 bytes, checksum: 07173b7d3884285218ba141bb85ab291 (MD5) / Made available in DSpace on 2017-05-12T21:06:34Z (GMT). No. of bitstreams: 1 DenilsonVieira.pdf: 1857476 bytes, checksum: 07173b7d3884285218ba141bb85ab291 (MD5) Previous issue date: 2012-08-31 / Himatanthus drasticus (Mart.) Plumel is popularly known in the North and Northeast Regions of Brazil as janaúba, janaguba, tiborna, jasmim-manga and pau-de-leite, as well. Brazilian traditional medicine knowledge attributes to the species antiinflammatory, analgesic, antitumoral and dewormer properties. Thus, the present study sought to investigate the anti-inflammatory, analgesic and wound-healing effects of the hidroalcoholic extract (HAE) made from Himatanthus dratiscus stem bark, which were collected in São Bento (MA) Brazil. Oral administration of HAE (0.5, 0.75 and 1.0 g/kg) reduced in a dose-dependent manner both oedema’s formation and leukocyte migration in mice submitted to intraplantar injection of 1% carragenin. Similarly, HAE also reduced the number of contortions in the acetic acid-induced writhing test. However, HAE had no effect on pain’s central perception. Corroborating these data, HAE showed significant wound-healing effect since it accelerated the wound contraction time in the mice. Finally, assessment of in vitro antioxidant activity of HAE suggested that phenolic compounds found in the extract is able to scavenger DPPH radical as fast as well-known antioxidants like -tocopherol. Therefore, this study shows that HAE promotes relevant analgesic, anti-inflammatory, woundhealing and antioxidant activity. Moreover, this study contributes to validation of popular use of the species as well as open up new perspectives for future investigations. / Himatanthus drasticus (Mart.) Plumel é popularmente conhecida nas regiões Norte e Nordeste do Brasil como janaúba, janaguba, tiborna, jasmim-manga, pau-de-leite entre outras denominações. Na prática popular, esta espécie é usada como antiinflamatória, antitumoral, analgésica e vermífuga. O presente estudo investigou os efeitos analgésico, anti-inflamatório, cicatrizante e antioxidante do extrato hidroalcoólico das cascas do caule da Himatanthus drasticus (EHA) coletadas no município de São Bento - MA. Quando administrado nas doses de 0,5; 0,75 e 1,0 g/kg (v.o.), o EHA reduziu de forma dependente de dose a formação de edema e a migração leucocitária em camundongos machos, submetidos a injeção intraplantar de carragenina 1%. De forma similar, o EHA reduziu o número de contorções abdominais induzidas por ácido acético 1%, evidenciando a atividade antinociceptiva. Entretanto, o EHA não promoveu qualquer efeito sobre a percepção central da dor. Em consonância com estes efeitos, o EHA também mostrou significante atividade cicatrizante, uma vez que, acelerou o tempo de contração da ferida induzida por excisão de pele nos camundongos. Finalmente, a avaliação da atividade antioxidante in vitro do EHA foi sugestiva de que a mistura fenólica presente no extrato é capaz de sequestrar o radical DPPH em velocidade semelhante a antioxidantes clássicos como o α-tocoferol. Sendo assim, este estudo mostra que o EHA das cascas da Himatanthus drasticus possui importante ação analgésica, anti-inflamatória, cicatrizante e antioxidante. Ademais, este estudo contribui para a validação do uso popular da espécie e abre perspectivas para novas investigações.

Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2015-04-08T22:07:57Z No. of bitstreams: 1 Isabella Vargas de Souza Lima.pdf: 9375405 bytes, checksum: a3d913a7254631a76ea5f2fc0da63ddc (MD5) / Made available in DSpace on 2015-04-08T22:07:57Z (GMT). No. of bitstreams: 1 Isabella Vargas de Souza Lima.pdf: 9375405 bytes, checksum: a3d913a7254631a76ea5f2fc0da63ddc (MD5) Previous issue date: 2012 / É reconhecida a interface entre a reumatologia, particularmente no que diz respeito às doenças autoimunes, e a infectologia, seja pela hipótese de agentes infecciosos atuando como gatilho das disfunções imunológicas, seja pelo risco infeccioso atribuído aos tratamentos imunossupressores. Adicionalmente, tem sido observada a produção de alguns autoanticorpos no curso de infecções. Por exemplo: em pacientes com tuberculose (TB), foi demonstrada a produção de anticorpos descritos como de alta especificidade para artrite reumatóide (AR) como os anticorpos antipeptídeos citrulinados (ACPAs) e, do mesmo modo, foi demonstrada a presença de anticorpos anticitoplasma de neutrófilos (ANCA) dentre os quais antiproteinase 3 (anti-PR3) e antimieloperoxidase (anti-MPO), que são marcadores de vasculites sistêmicas. Objetivos: a) revisar as publicações sobre positividade dos ACPAs em doenças infecciosas, b) pesquisar a prevalência destes anticorpos assim como do ANCA em uma população de portadores de tuberculose. Métodos: a) inicialmente foi realizada uma revisão sistemática sobre os estudos avaliando a presença de ACPAs em doenças infecciosas; b) posteriormente, um grupo de 50 pacientes com TB pulmonar não tratada ou com até 30 dias do início do tratamento foi avaliado quanto à presença de sintomas reumatológicos e, principalmente, quanto à positividade de anticorpos ACPAs, incluindo antipeptídeo citrulinado cíclico (anti-CCP) e antivimentina citrulinada modificada (anti-MCV) e quanto à positividade de ANCA por imunofluorescência indireta (IFI) e anticorpos anti-PR3 e anti-MPO por enzimaimunoensaio (ELISA). Resultados: a) a revisão sistemática foi publicada e encontra-se apresentada “Revisão de literatura” com o título Antibodies against cyclic citrullinated peptides in infectious diseases – a systematic review. Clin Rheumatol 2010, Dec 29(12): 1345-51. b) encontrou-se positividade de ACPAs em apenas dois (4%) dos 50 pacientes com TB e não houve positividade de ANCA por IFI ou a presença de anticorpos anti-PR3 ou anti-MPO por ELISA no soro desses pacientes. Estes resultados estão apresentados em dois artigos que foram submetidos para a revista Clinical Rheumatology (Canadá, fator de impacto 2011: 1,996), aguardando o parecer do corpo editorial. As versões submetidas encontram-se na sessão “Artigos”. Conclusões: embora estudos prévios tenham relatado a presença de ACPAs e ANCA em pacientes com TB, no presente estudo a positividade dos ACPAs foi baixa e não foi observada positividade para ANCA, anti-PR3 e anti-MPO, confirmando a alta especificidade destes testes para AR e vasculites sistêmicas, respectivamente.