The distribution of resources is vital to any system or society. This is particularly true of social insect colonies where independent access to resources is not available to all members. Only a fraction of individuals are responsible for obtaining food for the colony from outside the nest. Surprisingly little is known about how this food is subsequently distributed to members inside the nest. The work in this thesis is focused around a set of food distribution experiments conducted using four colonies of the ant Temnothorax albipennis. The study applies a well-used technique in a new way to investigate the distribution of food under two different scenarios: feeding under normal conditions and famine relief feeding after a period of starvation. All ants in each colony are marked and then individually tracked recording every feeding interaction to obtain a complete network of food transmission. This work has shown that all four colonies efficiently relieved the famine within 30 minutes of introducing new food. This process was facilitated by workers abandoning their spatial structure and expanding their space use; feeding multiple recipients from a single donor; and simultaneously spreading stored food and new food. Recruitment of foragers did not play a major role in relieving the famine but foragers were responsible for most of the first round of feeding. The study revealed that not all members received the same amount of food and most ants received food in multiple feeding interactions. The transmission pathways used to distribute the food present an opportunity for harmful substances to spread. The pathways are explored in this context to see whether the colonies might aim to minimize the spread by partitioning the pathways or maximise spread by mixing to promote social immunity. The study reveals behavioural differences between the four colonies which are likely to result from the inherent variation in demographic and geometric properties. These differences highlight the flexibility of ant colonies during problem solving under different conditions.

Conventional treatments for prostate cancer have significant limitations making it difficult to control the disease. Cyclopropabenzindoles (CBI) are more biologically potent, stable and synthetically accessible analogues of cyclopropapyrroloindole (CPI) anti-tumour antibiotics, such as duocarmycin-SA and CC1065. A polymeric prodrug carrying a CBI drug attached to the polymeric backbone through a PSA cleavable linker peptide has two modes of selectivity: activation by PSA and the EPR effect. To synthesise a 5-amino-seco-CBI analogue, 2,4-dinitronaphthalen- 1-ol gave di-Boc-1-iodonaphthalene-2,4-diamine in five steps (triflation, SNAr displacement with iodide, reduction (loss of iodine), protection and restoration of the iodine. For the amino-seco-CBI, it was important to discriminate between N2 and N4. Acidic removal of the Boc-group(s) resulted in deiodination. NMR investigations showed an unexpected Wheland-like cationic intermediate. N3 of naphthalene-1,3-diamine was selectively trifluoroacetylated and N1 was masked with Boc. Electrophilic iodination gave an orthogonally protected 1-iodonaphthalene-2,4-diamine. Allylation at the trifluoroacetamide was followed by free radical cyclisation with TEMPO trap. Removal of the trifluoroacetyl group allowed coupling to 5-(2-(dimethylamino)ethoxy)-1H-indole-2-carboxylic acid. Reductive removal of 2,2,6,6-tetramethylpiperidine, substitution of the exposed hydroxy group with chloride and removal of the Boc-group gave the amino-seco-CBI drug, 5-amino-1-chloromethyl-3-(5-(2-dimethylaminoethoxy)indole-2-carbonyl)-2,3-dihydro-1H-benz[e]indole. A DNA-melting assay confirmed that it binds very strongly to dsDNA causing a 13 deg. C increase in melting temperature. The drug was a highly potent cytotoxin in vitro, with IC50 = 18 nM against LNCaP prostate cancer cells. The polymeric prodrug system involved the synthesis of the pentapeptide SSKLQ. The amide side chain of glutamine can be masked as the nitrile and this can be quantitatively hydrated to the γ-carboxamide of L-Gln with hydroperoxide. The pentapeptide was coupled to 4-methoxynaphthalen-1-amine and to poly(ethylene glycol) as a model polymeric prodrug system. Efficient release of the model drug from the polymeric prodrug by PSA will allow this polymeric prodrug system to be adopted for the synthesised amino-seco-CBI drug.

Made available in DSpace on 2015-04-14T14:50:53Z (GMT). No. of bitstreams: 1 407730.pdf: 978627 bytes, checksum: 207551daea7acbf96e0c911484083687 (MD5) Previous issue date: 2008-10-29 / Herpes Simplex V?rus-1 (HSV-1) ? um membro da fam?lia Herpesviridae e subfam?lia alfaherpesvirinea bastante disseminado entre os seres humanos. Esse v?rus inicia seu processo de infec??o a partir das c?lulas epiteliais da superf?cie da pele e mucosas, atingindo o sistema nervoso perif?rico. O HSV-1 inicia a infec??o atrav?s da mucosa oral e fica localizado na forma latente no nervo trig?mio da face, algumas vezes, pela a??o de fatores end?genos ou ex?genos, esse v?rus volta a sua forma ativa, ocasionando a reincidiva . Nesse processo de reativa??o do v?rus ele pode se localizar, na mucosa oral (gengivoestomatite herp?tica), no nervo ?ptico (queratite herp?tica) e no sistema nervoso central (encefalite). No caso da gestante, a reativa??o herp?tica pode ser assintom?tica, o que pode infectar o filho no momento do parto, levando a danos neurol?gicos irrevers?veis ou a morte. O processo de lat?ncia ? coordenado por dois mecanismos principais, a express?o dos genes LAT e a resposta imunol?gica. As c?lulas da resposta imune que bloqueiam a reativa??o viral a partir do nervo s?o os linf?citos T CD8+ de mem?ria. Esses linf?citos ficam justapostos ? membrana do corpo celular do neur?nio, interagindo com o ep?topo SSIEFARL de uma glicopote?na gB do envelope viral. Os linf?citos T CD8+ SSIEFARL espec?ficos produzem citocinas, como IFN-g, que penetram no neur?nio e impedem a express?o de genes que est?o envolvidos na constru??o do caps?deo, determinantes para forma??o de novos v?rions. Quando o n?mero dessas c?lulas diminui, o v?rus volta a sua forma ativa. A prolifera??o e fun??o das c?lulas T CD8+ ? controlada por citocinas, principalmente a IL-15 e a IL-21. Muitos estudos indicam que elas t?m um papel na prolifera??o homeost?tica de c?lulas T CD8+. Nesse trabalho, foram elaboradas constru??es g?nicas com o DNA da IL-15 e da IL-21 para avaliar o potencial dessas citocinas na otimiza??o da resposta T CD8+ de mem?ria ao HSV-1. In vitro, a IL-21 aumentou a freq??ncia de c?lulas T CD8+, com ou sem estimula??o de TCR. Na fase efetora, a IL-15 e IL-21 aumentaram os n?meros de c?lulas T CD8+ ant?genoespec?ficas produtoras de IFN-g. Para os estudos de mem?ria foi utilizado um sistema de transfer?ncia de c?lulas SSIEFARL transg?nicas de camundongos CD90.2 doadores para camundongos CD90.1 receptores. Os camundongos receptores foram infectados com HSV-1 pela rota intraperitoneal e tratados com o plasm?deo contendo de cada citocina ou a combina??o deles, um plasm?deo que codificava a glicoprote?na gB do HSV-1 foi utilizado com fonte de ant?geno Os resultados mostraram que cada pIL-15 ou pIL-21 isoladamente induz a prolifera??o de c?lulas T CD8+ de mem?ria ao herpes e que a administra??o do ant?geno n?o teve grande influ?ncia. Por outro lado, a combina??o de pIL-15, pIL-21 e pgB foi mais eficiente, tanto no aumento dos n?meros de c?lulas T CD8+, quanto na express?o de IFN-g.

Made available in DSpace on 2015-04-14T14:50:54Z (GMT). No. of bitstreams: 1 408007.pdf: 7713390 bytes, checksum: bf92d92b7f1e311023e32849423ed23c (MD5) Previous issue date: 2008-12-17 / O carrapato Rhipicephalus (Boophilus) microplus ? um ectoparasito hemat?fago de bovinos, amplamente distribu?do nos rebanhos da Am?rica, ?sia, ?frica e Oceania. O uso de acaricidas ? o principal m?todo para o controle do carrapato, por?m o custo das drogas e da m?o-de-obra requerida para aplicar o tratamento, o aparecimento crescente de carrapatos resistentes a v?rios acaricidas, a perman?ncia de res?duos qu?micos nos alimentos e a polui??o ambiental decorrente do seu uso tornam importante o desenvolvimento de outras formas de controle. O desenvolvimento de um m?todo de controle imunol?gico como uma alternativa para o controle qu?mico depende da identifica??o de mol?culas antig?nicas que geram uma resposta imune protetora. Como bovinos desenvolvem resist?ncia ao carrapato durante sucessivas infesta??es, a an?lise da resposta imune desenvolvida por bovinos infestados pode tornar-se de grande import?ncia na busca por ant?genos protetores. ELISA e Western Blot foram utilizados para investigar o padr?o de respostas de anticorpos de seis bovinos infestados doze vezes com R. microplus (seis infesta??es pesadas seguidas por seis infesta??es leves) contra extratos de gl?ndula salivar, intestino e larva. Durante infesta??es pesadas foram observados n?veis maiores de IgGs reconhecendo extratos prot?icos de gl?ndula salivar, intestino e larva, e uma diminui??o no n?mero e no peso de carrapatos que completam o ciclo parasit?rio. O padr?o mudou iniciando na s?tima infesta??o, mostrando uma diminui??o nos n?veis de IgG, e um aumento inicial seguido por uma significante diminui??o na propor??o de carrapatos que completam o ciclo parasit?rio. O n?mero de mol?culas reconhecidas em Western Blot foi maior pelos soros das infesta??es pesadas do que das infesta??es leves, embora uma grande varia??o nos perfis detectados pode ser visto entre os bovinos. Esses resultados indicam que n?veis de anticorpos contra o carrapato n?o est?o necessariamente relacionados de forma direta com n?veis de resist?ncia. Al?m disso, infesta??es pesadas e leves parecem modular de forma diferente a magnitude da resposta humoral e possivelmente os mecanismos imunes na aquisi??o natural de resist?ncia ao carrapato.

Made available in DSpace on 2015-04-14T14:51:11Z (GMT). No. of bitstreams: 1 432438.pdf: 2038170 bytes, checksum: 505895940d1e38c8e3925441d22f197d (MD5) Previous issue date: 2011-03-29 / Vermes do g?nero Angiostrongylus s?o parasitos intra-arteriais em roedores. A. costaricensis vive no sistema mesent?rico, enquanto A. cantonensis habita as art?rias pulmonares de ratos. No homem, hospedeiro acidental destas parasitoses, elas causam a gastroenterite eosinof?lica e meningite devido ? migra??o de adultos jovens de A. cantonensis nos tecidos do sistema nervoso central. O exame parasitol?gico de fezes n?o pode ser utilizado para diagn?stico humano das angiostrongil?ases porque n?o s?o encontradas larvas nas fezes, o que torna importante o desenvolvimento de t?cnicas moleculares. Os m?todos de imunodiagn?stico empregando ant?genos brutos apresentam reatividade cruzada com outras parasitoses e tamb?m resultados falso-negativos. Com o objetivo de aprimorar o diagn?stico molecular das angiostrongil?ases, direcionamos os esfor?os na tentativa de reduzir a complexidade dos extratos de ant?genos a fim de encontrar prote?nas mais espec?ficas e sens?veis para o diagn?stico. Primeiramente foi testado o uso de ant?genos de A. cantonensis para o diagn?stico de A. costaricensis pela t?cnica de ELISA. A partir disso, ant?genos de tubo reprodutor (TR) de f?meas de A. cantonensis foram fracionados por diversas t?cnicas e sua reatividade a soros controle foi testada por Western blot (WB). Colunas de prote?na A foram incubadas com soro de pacientes infectados, por?m este fracionamento n?o teve sucesso. Foi realizado o fracionamento subcelular dos extratos TR e com a fra??o de ant?genos de membrana celular (F2) foi realizado o fracionamento por ponto isoel?trico. As fra??es de pH apresentaram reatividade espec?fica aos soros controle positivos quando submetidas ao WB, sugerindo que as prote?nas encontradas possam ser importantes alvos para o diagn?stico das angiostrongil?ases. A possibilidade de clonar as prote?nas de interesse para produ??o em grande escala, poder? constituir fonte permanente de ant?genos com redu??o do volume de trabalho e do emprego de animais no laborat?rio

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-05-28T12:30:06Z No. of bitstreams: 1 469532 - Texto Completo.pdf: 772339 bytes, checksum: b1ca6d60639abd0248f0ea693f8f7d1f (MD5) / Made available in DSpace on 2015-05-28T12:30:06Z (GMT). No. of bitstreams: 1 469532 - Texto Completo.pdf: 772339 bytes, checksum: b1ca6d60639abd0248f0ea693f8f7d1f (MD5) Previous issue date: 2015-03-04 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Introduction: There has been a continuous search for safe tests that can predict antibody-mediated rejection in organ transplants, and the positive complement dependent cytotoxic crossmatch, developed in the 1960?s, was until recently considered the gold standard and the main test for prediction of rejection. The new methods for assessing humoral immunity, notably flow cytometric crossmatching and the Luminex? technology significantly increased the sensitivity of these assessments, but also the complexity in the interpretation of these results, as well as in the correlation of different methodologies. Despite the sensitivity of these methods, not any donor-specific antibody detected by solid phase assay results in positive or negative crossmatch. Information obtained with the specificities (such as fluorescence intensity) of anti-HLA antibodies may define the immunological risk for the patient, assisting in the selection of the ideal donor, as well as in the immunosuppressive regimen, for prophylactic and therapeutic uses. Objectives: The present study aimed to establish a cut-off point at the fluorescence intensity of antibodies detected by the panel Single Antigen Beads of class I and II that correlates to positive flow cytometric crossmatching (FCXM). It also aimed to assess whether there are differences between the use of DSAs with higher MFI alone and the sum of all the DSAs of a given patient. Methodology: A cross-sectional study of two databases of results of panels (Luminex?) and flow cytometric crossmatching of patients on a waiting list for kidney transplantation registered at the Laborat?rio de Imunologia de Transplantes da Santa Casa de Miseric?rdia, in Porto Alegre. Database 1 was composed of 1,316 crossmatches against deceased donors and panels of anti-HLA antibodies for loci A, B and DRB1 performed in 2010. Database 2 was composed of 2,288 crossmatches against deceased donors and panels of anti-HLA antibodies for loci C and DQB1 performed between July 2013 and July 2014. As an inclusion criterion for both databases, only samples with results available in the Panel on the same date of the serum tested in flow cytometry crossmatches were used resulting in 834 samples in database 1. Besides, for database 2 only samples with donor-specific antibody (DSA) for loci C and or DQB1, resulting in 348 crossmatches. Results and Conclusions: we demonstrated that 97.6% of the patients with DSAs anti-HLA- ABDRB1 with MFI ? 5000 resulted in positive FCXM. These were the optimal MFI cut-off values for donor selection when we assessed sensitivity and specificity for correlation with positive flow cytometric crossmatching. For DSAs HLA-DQB1, fluorescence intensities above 15,000 MFI offer high specificity (97.8%). Anti-HLA-C sensitization is less frequent (n=40). Only 5 patients showed MFI?5000. Of these, the crossmatch was positive in only one patient (20%). Virtual crossmatch is a resource that can assist in making pre-kidney transplantation decisions. / Introdu??o: A busca por testes seguros que possam prever a rejei??o mediada por anticorpo em transplantes de ?rg?os tem sido cont?nua e a prova cruzada por citotoxicidade dependente de complemento, desenvolvida na d?cada de 60, at? pouco tempo era considerada padr?o ouro e principal teste preditor de rejei??o. Os novos m?todos de aferi??o da imunidade humoral, notadamente a prova cruzada por citometria de fluxo e a tecnologia Luminex?, aumentaram significativamente a sensibilidade destas avalia??es, mas tamb?m a complexidade na interpreta??o destes resultados, assim como na correla??o das diferentes metodologias Embora bastante sens?vel, nem todo anticorpo doador espec?fico detectado pelo teste de fase s?lida resulta em uma prova cruzada positiva ou com rejei??o. As informa??es obtidas com as especificidades (assim como a intensidade de fluoresc?ncia) dos anticorpos anti-HLA podem definir o risco imunol?gico do paciente, auxiliando a escolha do doador ideal, bem como do esquema imunossupressor, tanto profil?tico quanto terap?utico. Objetivos: O objetivo deste trabalho foi estabelecer um ponto de corte no n?vel de fluoresc?ncia de anticorpos detectados pelo painel Single Antigen Beads de classe I e II que se correlacione com a prova cruzada positiva por citometria de fluxo (XMCF). Tamb?m objetivou-se avaliar se existem diferen?as entre o emprego de apenas DSAs com maior MFI e a soma de todos os DSAs de um determinado paciente. Metodologia: Foi realizado estudo transversal de dois bancos de dados de resultados de Paineis (Luminex?) e prova cruzada por citometria de fluxo de pacientes em lista de espera para transplante renal cadastrados no Laborat?rio de Imunologia de Transplantes da Santa Casa de Miseric?rdia de Porto Alegre. O banco n?mero 1 era composto de 1316 provas cruzadas contra doadores falecidos e pain?is de anticorpos anti-HLA dos loci A, B e DRB1, realizados no ano de 2010. O banco n?mero dois era composto de 2288 provas cruzadas contra doadores falecidos e pain?is de anticorpos anti-HLA dos loci C e DQB1 realizadas entre julho de 2013 e julho de 2014. Como crit?rio de inclus?o para ambos os bancos de dados foram utilizadas somente amostras que possu?am resultados de Painel na mesma data do soro testado nas provas cruzadas por citometria de fluxo, resultando em 834 amostras no banco de n?mero 1. Al?m disso, para o banco de dados n?mero 2 foram utilizados apenas amostras que possu?am anticorpo espec?fico contra o doador (DSA) dos loci C e ou DQB1, resultando em 348 provas cruzadas. Resultados e Conclus?es: demonstramos que 97,6% dos pacientes com DSAs anti-HLA- ABDRB1 com MFI?5000 resultaram em XMCF positiva. Os n?veis de MFI nesta faixa corresponderam aos melhores pontos de corte de escolha quando avaliamos a sensibilidade e especificidade para a correla??o com a prova cruzada positiva por citometria de fluxo. Para os DSAs HLA-DQB1, n?veis de fluoresc?ncia acima de 15.000 MFI ofereceram elevada especificidade (97,8%). A sensibiliza??o anti-HLA-C ? menos frequente (n=40). Apenas 5 pacientes apresentaram MFI?5000. Destes, apenas em um (20%) a prova cruzada foi positiva. A prova cruzada virtual ? um recurso que pode auxiliar na tomada de decis?es pr?-transplante renal.

Made available in DSpace on 2015-04-14T13:09:31Z (GMT). No. of bitstreams: 1 437829.pdf: 3097644 bytes, checksum: 63052063f3fb08648c7ca5a4506262bc (MD5) Previous issue date: 2011-12-16 / The genus Angiostrongylus Kamensky, 1905 belongs to the Phylum Nematode, with round shape as its main feature. Two species have medical importance, A. costaricensis living in mesenteric arteries of wild mice and causing abdominal angiostrongyliasis in human and A. cantonensis which lives in pulmonary arteries of rats and may cause eosinophilic meningoencephalitis in humans. The diagnosis of both diseases is difficult due to absence of parasite in feces in case of the infection by A. costaricensis and seldom detected larvae in the cerebrospinal fluid in case of eosinophilic meningoencephalitis. Several studies have been performed to improve the diagnosis of angiostrongyliasis which should be able to differentiate in a specific and sensitive way among other parasitic infections. The 31kDa antigen has been considered the main antigen for eosinophilic meningoencephalitis diagnosis due to A. cantonensis infection. However this antigen is obtained from crude extracts of the worm by a laborious process of purification with low yielding and insufficient amount for large distribution to other diagnostic centers. In order to improve the serologic diagnostic of angiostrongyliasis and make the antigens widely available the present work aimed to identify new antigenic targets and also characterize the 31kDa antigen for further recombinant production. Besides that, essential molecules for parasite survival were investigated which in the future may be targets for disease treatment. Two sources of antigen from female worms were used: excretion and secretion products (ES) and total extract (TE). In ES, sample antioxidant enzymes activity were detected such as catalase and superoxide dismutase. Also was identified by Western blot and Mass spectrometry (MS), 17 proteins target for disease diagnosis and treatment like hemoglobinases, heat shock proteins and proteases inhibitors. In TE sample antioxidant enzymes as well as glutathione transferases (GST) which is another kind of defense enzyme were also detected. GSTs were purified by affinity chromatography and analyzed by MS. Peptide sequences from this experiment matched with homologous sequences of sigma class GST. In TE samples was possible to characterize the 31kDa and after two-dimensional electrophoresis was shown to be composed of four spots around 4.5 of isoelectric point (pI) and being recognized by sera from patients infected with Angiostrongylus spp. The spots were analyzed by MS and three different proteins were identified: 14-3-3 protein, NAC domain containing protein, and epsilon subunit of the coatomer protein complex isoform 2. The 31kDa antigen was characterized as a glycoprotein through studies of oxidation of carbohydrate where it was observed that the antigenicity of four spots was dependent on sugar residues. The DNA sequences of the antigens were obtained by random sequencing of the genome for 454 platform (Roche) and deposited in Genbank. The data generated in this study contribute significantly to the development of recombinant antigens that may be widely distributed for independent diagnostic validation / O g?nero Angiostrongylus Kamensky, 1905 agrupa animais pertencentes ao filo Nematoda, cuja caracter?stica marcante ? a forma corporal cil?ndrica. Duas esp?cies possuem import?ncia m?dica: A. costaricensis cujo habitat natural s?o as art?rias mesent?ricas de camundongos silvestres e na infec??o humana pode levar ao desenvolvimento de angiostrongil?ase abdominal; e A. cantonensis que habita as art?rias pulmonares de roedores e na infec??o humana pode causar meningoencefalite eosinof?lica. O diagn?stico de ambas as doen?as ? dificultado pela aus?ncia de formas parasit?rias nas fezes, no caso de infec??es por A. costaricensis e raramente encontradas no l?quido cefaloraquidiano no caso de meningoencefalite eosinof?lica. Muitos estudos v?m sendo desenvolvidos para o aprimoramento da detec??o das angiostrongil?ases visando testes que sejam capazes de discernir das diferentes infec??es parasit?rias de forma sens?vel e espec?fica. O ant?geno de 31kDa ? considerado atualmente o principal ant?geno para o diagn?stico da meningoencefalite eosinof?lica, causada por A. cantonensis, entretanto ? proveniente da purifica??o de extratos brutos do parasito o que acarreta num processo laborioso e dispendioso que em ?ltima an?lise gera quantidades insuficientes para que haja ampla distribui??o e compartilhamento entre os centros de diagn?stico. Com o intuito de aprimorar o diagn?stico sorol?gico das angiostrongil?ases e tornar os ant?genos dispon?veis globalmente o presente trabalho buscou identificar novos alvos antig?nicos e caracterizar o ant?geno de 31kDa para posterior propaga??o de formas recombinantes. Al?m disso, foram estudadas mol?culas que podem ser fundamentais na manuten??o do parasitismo, que futuramente poder?o ser alvos para o tratamento das angiostrongil?ases. Duas fontes de ant?genos a partir de vermes adultos f?meas foram empregadas: produtos de excre??o e secre??o (ES) e extrato bruto (TE). Nos ES foi detectada a atividade de enzimas antioxidantes como catalase e super?xido dismutase e identificadas, por western blot e espectrometria de massas (MS), 17 prote?nas alvo para o diagn?stico e tratamento das angiostrongil?ases dentre elas hemoglobinases, prote?nas de choque t?rmico e inibidores de proteases. Nas amostras de TE al?m da identifica??o de enzimas antioxidantes, estavam presentes glutationas transferases (GST), outra classe de enzimas de defesa. Estas prote?nas foram purificadas por cromatografia de afinidade e analisadas por MS o que revelou sequencias pept?dicas hom?logas a GST de classe sigma. Em TE tamb?m foi poss?vel a caracteriza??o do ant?geno de 31kDa que quando submetido a eletroforese bidimensional mostrou-se ser composto por 4 spots com ponto isoel?trico (pI) em torno de 4,5 sendo reconhecidos pelo soro de pacientes infectados com Angiostrongylus spp. Os spots foram analisados por MS e tr?s diferentes prote?nas foram identificadas: 14-3-3; prote?na com dom?nio NAC e a subunidade ?psilon do coatamero. O ant?geno de 31kDa foi caracterizado como uma glicoprote?na atrav?s de estudos de oxida??o de glic?deos, onde se observou que a antigenicidade dos 4 spots foi dependente de res?duos de a??car. As sequ?ncias de DNA dos ant?genos foram obtidas pelo sequenciamento aleat?rio do genoma pela plataforma 454 (Roche) e depositadas no Genbank. Os dados gerados no presente trabalho contribuem de forma significativa para o desenvolvimento de ant?genos recombinantes que poder?o ser amplamente distribu?dos para valida??o e aplica??o em diagn?stico

Made available in DSpace on 2015-04-14T13:09:35Z (GMT). No. of bitstreams: 1 440746.pdf: 8186310 bytes, checksum: 2ddc0fe8a6260707c7754fc8b9f27f5b (MD5) Previous issue date: 2012-05-07 / The Angiostrongylus genus includes two species that can infect humans, A. cantonensis and A. costaricensis. They may cause infections known as eosinophilic meningitis and abdominal angiostrongyliasis, respectively. In A. costaricensis infection, eggs and larvae are central elements in the inflammatory reactions, which may get worse with death of the worms. The currently available anthelmintics act on the parasite essential metabolic pathways with a killing effect. Therefore, an alternative substance to treat angiostrongyliasis, acting mainly in worms reproduction is necessary. An in vitro study conducted with Schistosoma mansoni showed inhibition of oviposition by Phenanthroline. In another study with Caenorhabditis elegans, it was shown that serotonin increases the egg-laying rate of the female nematode, besides controlling the change of its posture state (rest and activation). Serotonin is a neurotransmitter present in vertebrates and invertebrates. In order to test the effect on egg laying of Angiostrongylus spp., two substances that interfere with serotonin neurotransmission in humans, Buspirone and Pizotifen, were used in an experimental model in vivo. 28 rodents of species Rattus norvegicus were divided into three groups and infected with 100 L3 of A. cantonensis: a control group (untreated) and two groups treated with each substance. The substances were administered as soon as all rodents started releasing larvae, once a day, orally, for 10 days, at a concentration of 0.03 mg / mL each. In this period rodent feces were collected daily for counting the number of L1 and after 10 days the animals were euthanized for collection of the worms. The average number of larvae released in feces was 37,934 by the Control group, 10,658 by the Buspirone group and 6,658 by the Pizotifen group. The worms were counted and separated by sex: in the Control group 59 females and 40 males were obtained; in Buspirone group 86 females and 41 males were found; and in the Pizotifen group 83 females and 64 males were counted. The comparison of data from Control and Experimental groups was statistically analyzed by ANOVA and no significant difference was observed. Females were measured using a millimetric eyepiece installed in a stereomicroscope. The ANOVA analysis resulted in a significant difference between Control and Pizotifen, which had an average size of 18 mm, compared with to average size of 19 mm of Control, indicating that Pizotifen would have some effect in the nematodes development, but not affecting their reproduction. These results indicate that the search for alternative drugs that act on egg laying needs a better understanding of the pathways that regulate the reproductive system of parasitic organisms. / O g?nero Angiostrongylus engloba duas esp?cies A. cantonensis e A. costaricensis, que podem infectar o ser humano e causar infec??es conhecidas como meningite eosinof?lica e angiostrongil?ase abdominal, respectivamente. Na infec??o por A. costaricensis, ovos e larvas s?o elementos centrais nas rea??es inflamat?rias podendo haver o agravamento dessas les?es, pela morte dos vermes. Os anti-helm?nticos atualmente dispon?veis, atuam em vias metab?licas essenciais ao parasito, culminando com a morte dos vermes. Portanto, uma droga alternativa para o tratamento das angiostrongil?ases, que atue principalmente na reprodu??o dos vermes, se torna necess?ria. Um estudo in vitro realizado com Schistosoma mansoni demonstrou a inibi??o da oviposi??o pela fenantrolina. Em outro estudo com Caenorhabditis elegans foi demonstrado que a serotonina estimula o aumento da taxa de ovos liberados pela f?mea do nemat?deo, al?m de controlar a altera??o do seu estado de postura (repouso e ativa??o). A serotonina ? um neurotransmissor presente tanto em vertebrados como em invertebrados. Com o objetivo de testar o efeito na oviposi??o de Angiostrongylus cantonensis, duas subst?ncias que interferem na neurotransmiss?o da serotonina em humanos, Buspirona e Pizotifeno, foram utilizadas em modelo experimental in vivo. 28 roedores da esp?cie Rattus norvegicus foram divididos em 3 grupos e infectados com 100 L3 de A. cantonensis: um grupo controle (n?o tratado) e 2 grupos tratados com cada subst?ncia. As subst?ncias foram administradas a partir do momento em que todos os roedores iniciaram a larvipostura, uma vez ao dia por via oral, durante 10 dias, numa concentra??o de 0,03 mg/mL cada. Neste per?odo as fezes dos roedores foram recolhidas diariamente para a contagem do n?mero de L1 eliminadas e, ap?s os 10 dias, os animais foram eutanasiados para coleta dos vermes. A m?dia de larvas eliminadas nas fezes para o grupo controle foi 37.934, para o grupo Buspirona 10.658 e para o grupo Pizotifeno 6.658. Os vermes foram contados e separados pelo sexo: no grupo controle foram obtidas 59 f?meas e 40 machos; no grupo Buspirona foram encontradas 86 f?meas e 41 machos e no grupo Pizotifeno 83 f?meas e 64 machos. A compara??o dos dados dos grupos experimentais e do controle foram analisadas estatisticamente pelo teste ANOVA e nenhuma diferen?a significativa foi verificada. As f?meas foram medidas atrav?s de uma ocular milimetrada instalada em um estereomicrosc?pio. A an?lise foi feita tamb?m pelo teste ANOVA e resultou numa diferen?a significativa entre o grupo controle e o Pizotifeno, no qual teve um tamanho m?dio de 18 mm, em compara??o com o tamanho m?dio do controle de 19 mm, indicando que o Pizotifeno poderia ter algum efeito no desenvolvimento dos nemat?deos, por?m n?o afetando a reprodu??o. Estes resultados indicam que para a procura de drogas alternativas, que atuem na oviposi??o, ? necess?rio uma melhor compreens?o das vias reguladoras do sistema reprodutivo dos organismos parasitos.

Since the 1990’s Open Access has developed into an alternative model for scientific publication. Today an increasing political interest in promoting Open Access is commonly channeled through the implementation of policies by research funders. However, in the scientific community the uptake and acceptance of the model has been of notably different character.This Master’s thesis examines the understanding of and attitudes towards open access among eight senior Swedish researchers and how these have been affected by the implementation of the Swedish Research Council’s Open Access-policy as implemented in 2010. It further asks the question of how researchers’ publishing practices can be understood as shaped by and performed within actor-network configurations. The study is based on interviews with researchers from three academic disciplines. The empirical material has been analyzed through the perspective of actor-network theory.The study finds that the impact of the Swedish Research Council’s policy has been low. Yet, perceived as a floating object, the policy has forced the researchers to adhere to and position themselves in relation to the immanent powers of the policy and, thus, to Open Access both as movement and publishing model. The study also finds that both the traditional model for scientific publishing and the Open Access model can be understood as actor-networks, currently competing for the researchers’ loyalty and involvement in order to secure future dominance. The study finally concludes that in order to fully understand researchers’ practices and attitudes it is necessary to perceive these as shaped in and by extra-social contexts and forces. / Program: Masterutbildning: Digitala tjänster - kultur, information & kommunikation

This thesis discusses and analyses the existence of two different perspectives, a social and a technical one, in Library and Information Science (LIS). Most of the time the division between these perspectives seems to result in research only using either of them. This can be a problem when studying complex phenomena. We therefore see a need for a metatheory that unites the social and the technical. By presenting and analysing all doctoral dissertations published at the Swedish School of Library and Information Science (SSLIS) 1993-2005, we try to detect and critically discuss the dichotomy between the two perspectives. The analysis of the dissertations is done with an Actor-network theory (ANT) perspective. The outcome is that most of the dissertations are written using either a social or a technical perspective, though not all of them. As a way out of the division between the social and the technical, we discuss the possibilities for ANT as a new metatheory for LIS. A few examples of international ANT writings in LIS are also presented briefly to show the possibilities of that metatheory. / Uppsatsnivå: D