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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.
211

EXPRESSÃO E CARACTERIZAÇÃO DE UM FRAGMENTO DA GLICOPROTEÍNA E DO HERPESVÍRUS BOVINO TIPO 1 E USO EM UM TESTE SOROLÓGICO DIFERENCIAL / EXPRESSION AND CHARACTERIZATION OF A TRUNCATED FORM OF BOVINE HERPESVIRUS TYPE 1 ENVELOPE GLYCOPROTEIN E AND ITS USE IN A DIFFERENTIAL SEROLOGICAL TEST

Oliveira, Stephan Alberto Machado de 05 March 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Bovine herpesvirus type 1 (BoHV-1) is distributed worldwide and produces high economic losses to the in livestock industry. BoHV-1 infection causes respiratory, reproductive and may also be associated with neurological signs. There are several tests that can diagnose the infection, however, serological techniques currently used are not able to differentiate antibodies produced by vaccination from those produced in response to natural infection. What is sought is a mean to differentiate vaccinated animals of those infected by the field strain. Vaccines with deletion in the glycoprotein E (gE) gene have been developed for this purpose. However, this also requires the development of tests capable to differentiate the serological response between infected and vaccinated animals. To this end, a 651 nucleotide fragment corresponding to the amino-terminal third (217 amino acids) of the BoHV-1 gE gene - that shares a high identity with the homologous BoHV-5 counterpart - was cloned as a 6×His-tag fusion protein in an Escherichia coli expression vector pET16b. A soluble protein of approximately 25 kDa was purified from lysates of transformed E. coli. The recombinant protein was detected in Western blot (WB) by anti-6-his tag and anti BoHV-1 gE monoclonal antibodies. Antibodies present in the sera of cattle infected with BoHV-1 and BoHV-5 reacted specifically with the 25 kDa recombinant protein in WB. Moreover, mice immunized with the purified protein developed antibodies that recognized the viral gE in lysates of cell monolayers infected with BoHV-1 and BoHV-5. An indirect ELISA for gE antibodies, based on the expressed protein, was able to differentiate serologically calves vaccinated with a gE-deleted BoHV- 5 strain from calves experimentally infected with BoHV-1 or BoHV-5. These data demonstrate that the antigen retained its immunological properties and, thus, can be used in serological tests for bovine herpesvirus infections. It has a potential use in a indirect ELISA to differentiate naturally infected animals from those vaccinated whit the recombinant, gE-negative strains. / O herpesvírus bovino tipo 1 (BoHV-1) é um vírus de distribuição mundial e produz grandes prejuízos econômicos em rebanhos de corte e de leite. A infecção pelo BoHV-1 produz manifestações respiratórias, reprodutivas e também pode cursar com sinais nervosos. Existem diversos testes laboratoriais capazes de diagnosticar a infecção. Contudo, as técnicas sorológicas empregadas atualmente não são capazes de diferenciar anticorpos produzidos pela vacinação daqueles produzidos em resposta à infecção natural. Assim, vacinas diferenciais com deleção da glicoproteína E (gE) têm sido desenvolvidas com essa finalidade. No entanto, necessita-se também de testes capazes de diferenciar a produção de anticorpos vacinais dos induzidos pelo vírus vacinal. Com essa finalidade, essa dissertação relata a expressão e caracterização de um fragmento da glicoproteína E do BoHV-1 e seu uso no desenvolvimento e padronização de um ELISA indireto para detecção de anticorpos anti-gE. Um fragmento de 651 nucleotídeos correspondente ao terço amino-terminal (217 aminoácidos) do gene da gE do BoHV-1, que possui uma alta identidade com o homólogo herpesvírus bovino tipo 5 (BoHV-5), foi clonado com proteína de fusão 6xHis-tag em Escherichia coli utilizando vetor de expressão pET16b. Uma proteína solúvel de aproximadamente 25kDa foi purificada a partir de lisados de E. coli transformadas. A proteína recombinante foi detectada por Western blot (WB) por anticorpos monoclonais anti-histidina e anti-gE do BoHV-1. Anticorpos presentes no soro de animais infectados com BoHV-1 e BoHV-5 reagiram especificamente com a proteína recombinante no WB. Além disso, camundongos imunizados com a proteína purificada desenvolveram anticorpos que reconheceram a gE viral proveniente de lisados de monocamadas celulares infectadas com BoHV-1 e BoHV-5. Um ELISA indireto para detecção de anticorpos anti-gE, baseado na proteína expressa, foi capaz de diferenciar sorologicamente animais vacinados com a cepa gE deletada do BoHV-5 dos animais experimentalmente infectados com BoHV-1 ou BoHV-5. Esses resultados demonstram que o antígeno obtido conservou suas características imunológicas e pode ser utilizado na detecção sorológica das infecções por herpesvírus bovinos. Possui potencial para uso em grande escala como antígeno em testes de ELISA para diferenciar animais naturalmente infectados de animais vacinados com a cepas defectivas na gE
212

Gelatinases, their tissue inhibitors and p53 in lymphomas

Kyllönen, H. (Heli) 26 May 2009 (has links)
Abstract Lymphomas are a heterogeneous group of malignancies, which usually have a good prognosis and high cure rates. Lymphomas are sensitive to chemotherapy and radiotherapy, and many patients can be cured even after a relapse, resulting in a need for effective follow-up. However, the cost-benefit ratio of radiological imaging in predicting the forthcoming relapses is poor. Consequently, there is a need for biological prognostic and predictive markers to distinguish patients at the highest risk of relapse at the time of diagnosis or during follow-up. Despite rapid progress in lymphoma treatments, some patients still die from lymphoma. Thus, more data on the basic biological features of lymphomas are also needed. Gelatinases (MMP-2 and MMP-9) and their tissue inhibitors (TIMP-1 and TIMP-2) have been found to play a role in the progression of solid tumours. TP53 is a tumour suppressor gene, the mutations and protein over-expression of which have been demonstrated to be associated with survival in most cancer types. There is also some evidence that these proteins could have prognostic significance in lymphomas as well. In the present study, the tissue expression, plasma concentrations and clinical value of gelatinases and their tissue inhibitors were evaluated in lymphomas. 249 primary tissue samples from patients with Hodgkin, follicular, or diffuse large B-cell lymphoma were analysed for expression of gelatinases and/or their inhibitors using immunohistochemistry. In follicular lymphoma, p53 protein expression was also investigated. The plasma samples of 126 lymphoma patients and a control group of 44 healthy volunteers were collected and studied by ELISA. TIMP-1 expression correlated with bulky tumour and nodular sclerosis subtype of Hodgkin lymphoma. In follicular lymphoma, p53 over-expression was an independent adverse prognostic factor for survival and a predictor of histological transformation. Plasma MMP-2-TIMP-2 complex appeared to be a potential follow-up marker predicting the risk of relapse in lymphoma patients. Plasma levels of the MMP-2-TIMP-2 complex, proMMP-2, TIMP-2 and proMMP-2/TIMP-2 ratio were at abnormal levels both in patients with newly diagnosed lymphoma and those in remission compared to healthy controls. The clinical significance of these markers needs further studies.
213

Expression of human coronavirus NL63 and SARS-CoV nucleocapsid proteins for antibody production

Mnyamana, Yanga Eddie January 2012 (has links)
>Magister Scientiae - MSc / Human Coronaviruses (HCoVs) are found within the family Coronaviridae (genus, Coronavirus) and are enveloped, single-stranded, positive-sense RNA viruses. Infections of humans by coronaviruses are not normally associated with severe diseases. However, the identification of the coronavirus responsible for the outbreak of severe acute respiratory syndrome (SARS-CoV) showed that highly pathogenic coronaviruses can enter the human population. The SARS-CoV epidemic resulted in 8 422 cases with 916 deaths globally (case fatality rate: 10.9%). In 2004 a group 1 Coronavirus, designated Human Coronavirus NL63 (HCoV-NL63), was isolated from a 7 month old Dutch child suffering from bronchiolitis. In addition, HCoV-NL63 causes disease in children (detected in approximately 10% of respiratory tract infections), the elderly and the immunocompromised. This study was designed to express the full length nucleocapsid (N) proteins of HCoV-NL63 and SARS-CoV for antibody production in an animal model. The NL63-N/pFN2A and SARSN/ pFN2A plasmid constructs were used for this study. The presence of the insert on the Flexi ® vector was confirmed by restriction endonuclease digest and sequence verification. The sequenced chromatographs obtained from Inqaba Biotec were consistent with sequences from the NCBI Gen_Bank. Proteins were expressed in a KRX Escherichia coli bacterial system and analysed using 15% SDS-PAGE and Western Blotting. Thereafter, GST-tagged proteins were purified ith an affinity column purification system. Purified fusion proteins were subsequently cleaved with Pro-TEV Plus protease, separated on 15% SDS-PAGE gel and stained with Coomassie Brilliant Blue R250. The viral fusion proteins were subsequently used to immunize Balbc mice in order to produce polyclonal antibodies. A direct ELISA was used to analyze and validate the production of polyclonal antibodies by the individual mice. This is a preliminary study for development of diagnostic tools for the detection of HCoV-NL63 from patient samples collected in the Western Cape. / South Africa
214

Uso do óleo de arroz na cicatrização de úlceras cutâneas em ratos (Rattus norvegicus albinus) / Use of rice oil for treatment of cutaneous ulcers (Rattus norvegicus albinus)

Lania, Bruno Grosselli, 1987- 22 August 2018 (has links)
Orientadores: Paulo Eduardo Neves Ferreira Velho, Maria Letícia Cintra / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-22T07:25:40Z (GMT). No. of bitstreams: 1 Lania_BrunoGrosselli_M.pdf: 3238329 bytes, checksum: 957e602fc97c4a033665229ade46faca (MD5) Previous issue date: 2013 / Resumo: Introdução: o processo de cicatrização é longo e complexo, dura meses nos humanos, e depende de diversos fatores locais e gerais. Ele pode ser divido em três fases: inflamatória, proliferativa e de remodelação. Para que ocorra, é necessária uma cascata de eventos e a participação de diversos tipos de células, bem como de substâncias por elas secretadas. Entre estas destacam-se as substâncias pró-cicatriciais, como a leptina, IL-2, IL-4, IL-6 e o IGF-1, as anti-cicatriciais, como a adiponectina, IL-12, o IFN-?, o IFN-? e, finalmente, o TNF-?, que possui ação variável, de acordo com a concentração circulante desta substância. Muito há para se pesquisar nesse campo, e o desenvolvimento de produtos, com princípios ativos que estimulam a cicatrização, mas de baixo custo, que aproveite matérias-primas encontradas na região, poderia beneficiar um número grande de indivíduos. Foi demonstrado que o uso do óleo do farelo de arroz induz a proliferação de linfócitos, a síntese de citocinas, o aumento da hematopoese e a atividade fagocítica de macrófagos. Objetivos: testar a efetividade do óleo de arroz na cicatrização de feridas cutâneas, e avaliar, tanto no tecido lesado, como no sangue, a sua ação em fatores que atuam na cicatrização. Material e métodos: sobre feridas cirúrgicas circulares produzidas pela exérese da pele, com bisturi, no dorso de ratos, (45 animais, divididos em três grupos) foi aplicado um produto à base de óleo de arroz (patente BR 10 2012 008718 9). O processo de cicatrização foi avaliado por meio do estudo histológico e da quantificação tissular (por meio da PCR real time) e sérica (por meio da técnica Elisa), de fatores que atuam na cicatrização: leptina, IL-2, IL-4, IL-6, IGF-1, adiponectina, IL-12, IFN-?, IFN- ? e TNF- ?. Resultados e conclusões: comparativamente com o controle, foi encontrada diferença significante na celularidade das feridas e detectada ação sistêmica do produto, face ao aumento dos níveis séricos de adiponectina, leptina, IL-2, IL-6, TNF-? e IFN-?. Os resultados deste trabalho poderão ser úteis para a indústria farmacêutica e cosmecêutica brasileira ou internacional / Abstract: The wound healing process is long and complex, lasts months and depends on many local and general factors. It can be divided into three phases: inflammatory, proliferative and remodeling. For that to occur, it is necessary a cascade of events involving several cell types, as well as substances secreted by them. Among these we highlight the pro-healing substances such as leptin, IL-2, IL-4, IL-6 and IGF-1, anti-scarring such as IL-12, IFN-?, IFN- ? and, finally, TNF-?, which possesses variable action, according to the circulating concentration of this substance. More research is needed in this field, and the development of products with active ingredients that stimulate healing, but of low cost, which uses raw materials found in the region, could benefit a large number of individuals. It has been shown that the use of rice bran oil induces lymphocyte proliferation, cytokine synthesis, increased hematopoiesis and phagocytic activity of macrophages. The objectives of this study were to test the effectiveness of rice oil topical use and assess both the injured tissue and blood to evaluate its action on factors that act in healing. Methods: Circular surgical wounds were produced by excision of skin with a scalpel in the back of rats (45, divided into three groups), then applied saline solution or essentials fatty acids or rice bran oil (patent BR 10 2012 0087 18 9). The healing process was evaluated by histological examination and quantification of tissue (by real time PCR) and serum (by ELISA technique), factors that act in healing, namely leptin, IL-2, IL -4, IL-6, IGF-1, adiponectin, IL-12, IFN-?, IFN-? and TNF-?. Compared with control, there was significant difference in the cellularity of the wound healing area and systemic action of the product detected by the increases in serum levels of adiponectin, leptin, IL-2, IL-6, TNF-? and IFN -?. The results of this study may be useful to the Brazilian or international pharmaceutical and cosmeceutical industry / Mestrado / Clinica Medica / Mestre em Clinica Medica
215

Desenvolvimento de modelo animal de leucemia linfóide aguda pediátrica : teste ELISA para monitorar a progressão da leucemia / Acute lymphoblastic leukemia animal model development : leukemia progression monitoring by ELISA

Milani, Mateus, 1985- 02 December 2014 (has links)
Orientador: José Andrés Yunes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T08:28:04Z (GMT). No. of bitstreams: 1 Milani_Mateus_M.pdf: 3959646 bytes, checksum: a36674e099fefbc487286cdc33006c0a (MD5) Previous issue date: 2014 / Resumo: A leucemia linfoide aguda (LLA) é o câncer mais comum na infância. O transplante de células primárias de LLA humana em camundongos imunosuprimidos tem sido de suma importância para o entendimento da fisiopatologia da doença e para o teste de novos fármacos. Ao contrário de modelos animais de tumores sólidos, cujo volume é facilmente medido na superfície dos animais, a LLA infiltra órgãos inacessíveis ao exterior, daí a necessidade de definir métodos adequados para o monitoramento da progressão da doença. Resultados aqui apresentados indicam que proteínas secretadas pela LLA podem servir como marcadores quantitativos da carga leucêmica, facilmente aferidos por ELISA de amostras de plasma sanguíneo. Dentre três proteínas testadas (B2M, IGFBP2 e Hsp90), o ELISA de Hsp90 apresentou sensibilidade superior à análise da porcentagem de células leucêmicas no sangue dos animais, por citometria de fluxo de células marcadas com anti-huCD45. Os níveis de Hsp90 humano no plasma sanguíneo mostraram-se positivamente correlacionados com o porcentual de células leucêmicas na medula óssea e fígado e em menor grau com os níveis do baço e sangue periférico (SP) ao longo do tempo, tanto nas LLA de linhagem B quanto nas LLA-T. O ELISA de Hsp90 permite detectar a instauração da leucemia nos animais transplantados, até duas semanas antes da detecção pelo método tradicional de análise de sangue periférico por citometria de fluxo. Ao contrário do observado para IGFBP2, o tratamento dos animais leucêmicos com Dexametasona ou um inibidor da PI3K não interferiu nos níveis de Hsp90, que se mantiveram proporcionais à porcentagem de células leucêmicas huCD45+ no sangue periférico. No conjunto, os resultados demonstram que a análise do plasma dos animais por ELISA de Hsp90 é um método melhor do que os atualmente utilizados, para diagnóstico precoce e acompanhamento de LLA humana quando em níveis de doença residual mínima, ou seja, quando a porcentagem de células de LLA é inferior a 5% do total de células da medula óssea / Abstract: Acute lymphoblastic leukemia (ALL) is the most common type of childhood cancer . The transplantation of human primary ALL cells in immunodeficient mice has been of much importance for understanding the disease's pathophysiology and testing new drugs. Unlike animal models of solid tumors whose volume is easily measured on the animal surface, the ALL infiltrates organs that are inaccessible to external antigens, hence the need to define more suitable methods for monitoring the disease's progression. Results presented here indicate that proteins secreted by the ALL can serve as quantitative markers of leukemic burden and are easily measured by ELISA of blood plasma samples. Among three tested proteins (B2M, IGFBP2 and Hsp90), Hsp90 ELISA analysis showed higher sensitivity than the analysis of leukemic cells on animal blood by flow cytometry of anti- huCD45 labeled cells. The levels of Hsp90 in human blood plasma were shown to be positively correlated with the percentage of leukemic cells in the bone marrow and liver and to a lesser extent with the levels in the spleen and peripheral blood (PB) over time, both in B-lineage ALL as in ALL-T. The Hsp90 ELISA allows the leukemia's engraftment detection in transplanted animals up to two weeks prior to detection by the traditional method of peripheral blood analysis by flow cytometry. Unlike observed for IGFBP2, treatment of leukemic animals with Dexamethasone or PI3K inhibitors did not interfere in Hsp90 levels, which remained proportional to the percentage of huCD45+ leukemic cells in the peripheral blood. Taken together, the results demonstrate that the analysis of animal plasma by Hsp90 ELISA is a better method than those currently used for early diagnosis and monitoring of human ALL on minimal residual disease levels, when the percentage of ALL cells is less than 5 % of the total bone marrow cells / Mestrado / Genetica Animal e Evolução / Mestre em Genética e Biologia Molecular
216

The development of a university-based sex counselling programme in the age of AIDS.

Nicholas, Lionel John January 1993 (has links)
Philosophiae Doctor - PhD / The sexual behaviours, attitudes, beliefs and communication of 1896 black first-year university students were examined by means of a structured questionnaire for their contribution to the development of a university-based sex counselling programme. The areas of sexuality investigated included intra-familial communication about contraception and sexuality, belief in sex myths, knowledge of and myths about AIDS and the manner of acquisition of sex knowledge. The results of this study are consistent in reflecting much greater deficits in the knowledge of respondents about sexuality than encountered in the literature. Statistically significant gender differences were found for intra-familial communication about contraception, prejudice towards AIDS victims, knowledge of the modes of HIV infection, prejudice towards homosexuals, belief in myths about sexuality, age at which sex information was acquired, the preferred source of information about sexuality, attitude towards pre-marital intercourse, experience of pre-marital intercourse, belief about the acceptability of abortion, experience of pre-marital intercourse and worry about masturbation. No gender differences were found for belief in myths about high-risk AIDS infection, exposure to sex information within educational institutions and approval of sex education. The statistically significant gender differences which were found for most of the questionnaire items reflect the different sexual socialization experiences of respondents. Male and female students may therefore require counselling interventions geared to their respective needs Concern about AIDS has become central to university student sexual behaviour as well as protection against rape and sexual harassment and male responsibility for contraception. All campus counsellors will eventually experience the impact of AIDS and other sexually·transmitted diseases in their sessions with clients. Sexual harassment, rape, contraceptive failure and abortion will also increasingly impact on counselling sessions and require the university-based counsellor's involvement in broader university-wide prevention programmes as well as group based interventions. The development of a university-based sex counselling programme requires comprehensive interventions ranging from individual counselling to human sexuality courses. An awareness of the high profile sexuality problems as perceived by students, is essential for the development of preventive programmes at the group and academic class level as well as at the level of inf luencing uni versi ty policy. Knowledge of the merits of different theoretical positions and interventions for particular sexual problems is crucial for counselling intervention or referral. A systemic model of intervention for sexuality problems is proposed. The task of university-based sex counselling programmes is made more onerous by the paucity and ineffectiveness of sex information students are exposed to, the lack of sex education in the schools and the inadequate quality and degree of intrafamilial communication about sexuality. A significant proportion of respondents engage in pre-marital sexual intercourse without the benefit of adequate sex knowledge. The results of this study emphasize the need for research on the sexuality of, black South Africans, the particular vulnerabilities of first-year university students to sexuality problems and the dire need for structured sex education programmes at school as well as university.
217

Identification of toll-like receptor 9 as parapoxvirus ovis-sensing receptor in plasmacytoid dendritic cells: Identification of toll-like receptor 9 as parapoxvirusovis-sensing receptor in plasmacytoid dendritic cells

von Buttlar, Heiner, Siegemund, Sabine, Büttner, Matthias, Alber, Gottfried January 2014 (has links)
Parapoxvirus ovis (PPVO) is known for its immunostimulatory capacities and has been successfully used to generate vector vaccines effective especially in non-permissive host species. Murine conventional and plasmacytoid dendritic cells (cDC and pDC) are able to recognize PPVO. The PPVO-sensing receptor on pDC is hitherto unknown. In this study we aimed to define the pattern recognition receptor responsible for the activation of murine pDC by inactivated and replication-competent PPVO. We show that PPVO-induced expression of type I and type III interferons, pro-inflammatory cytokines, and costimulatory CD86 by bone marrow-derived pDC but not cDC is blocked by chloroquine, an inhibitor of endosomal maturation. The activation of pDC is independent of viral replication and depends mainly on TLR9. Moreover, the use of phosphatidylinositol 3-kinase inhibitor wortmannin or C-Jun-N-terminal kinase inhibitor SP600125 results in significant reduction of PPVO-induced pDC activation. Taken together, our data identify endosomal TLR9 as PPVO-sensing receptor in pDC.
218

Ability of ELISAs to detect antibodies against porcine respiratory and reproductive syndrome virus in serum of pigs after inactivated vaccination and subsequent challenge: Ability of ELISAs to detect antibodies against porcine respiratory andreproductive syndrome virus in serum of pigs after inactivated vaccination and subsequent challenge

Sattler, Tatjana, Pikalo, Jutta, Wodak, Eveline, Schmoll, Friedrich January 2016 (has links)
Background: In this study, six enzyme-linked immunosorbent assays (ELISA), intended for routine porcine reproductive and respiratory syndrome virus (PRRSV) herd monitoring, are tested for their ability to detect PRRSV specific antibodies in the serum of pigs after vaccination with an inactivated PRRSV type 1 vaccine and subsequent infection with a highly pathogenic (HP) PRRSV field strain. For this reason, ten piglets (group V) from a PRRSV negative herd were vaccinated twice at the age of 2 and 4 weeks with an inactivated PRRSV vaccine. Ten additional piglets (group N) from the sameherd remained unvaccinated. Three weeks after second vaccination, each of the piglets received an intradermal application of an HP PRRSV field strain. Serum samples were taken before first vaccination as well as before and 3, 7, 10 and 14 days after HP PRRSV application. All serum samples were tested for PRRSV RNA by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) as well as for PRRSV antibodies with all six study ELISAs. Results: At the beginning of the study (before vaccination), all of the piglets were PRRSV antibody negative with all study ELISAs. They also tested negative for PRRSV RNA measured by RT-qPCR. From day 3 after HP PRRSV application until the end of the study, a viremia was detected by RT-qPCR in all of the piglets. On day 0 (day of HP PRRSV application), nine out of ten piglets of the pre-vaccinated group tested PRRSV antibody positive with one of the tested ELISAs, although with lower S/P values than after infection. On day 10 after HP PRRSV application, all study ELISAs except one had significantly higher S/P or OD values, respectively more positive samples, in group V than in group N. Conclusions: Only one of the tested ELISAs was able to detect reliably PRRSV antibodies in pigs vaccinated with an inactivated PRRSV vaccine. With most of the tested ELISAs, higher S/P values respectively more positive samples after PRRSV infection were seen in the pre-vaccinated group than in the non-vaccinated.
219

Mitigating the impact of antidrug antibodies against insulin on ELISA assay

Bøwadt, Thea January 2021 (has links)
Diabetes has, in the past three decades, surged immensely. Because of this, new insulin analogues are constantly in the making.  In clinical studies, the presence of antidrug antibodies can prove a challenge when measuring insulin. In order to overcome the interference from antidrug antibody complexes on the total insulin measurement in human serum, several pre-treatment methods on insulin and polyclonal antibodies spiked samples were tried using ELISA analysis. Several different methods were tried, acid dissociation using a glycine buffer with and without ethanol in different concentrations, high ionic strength dissociation using MgCl2, Polyethylene glycol (PEG) and filtration. The best results were found when using the acid dissociation technique. Using glycine promising results were achieved, especially when 20 % ethanol was added to the acid mixture. Pre-treatment using PEG, MgCl2 and filtration was unsuccessful with the methods used. The main goal was reached through the use of glycine with the addition of 20% ethanol for acid dissociation. The proposed method still leaves significant room for optimisation and needs further verification on real patient samples. However, it is a good step in the direction of a global methodology using ELISA to overcome antidrug antibody interference for total insulin measurement in human serum.
220

Influence d'un phosphate de calcium substitué en strontium sur la physiologie de l'ostéoblaste humain en culture et évaluation de son potentiel de réparation osseusse chez la souris / Strontium substituted calcium phosphate influence on human osteoblasts physiology and evaluation of his potential bone healing capability on a mouse model.

Braux, Julien 02 February 2011 (has links)
Les phosphates de calcium sont des biomatériaux couramment utilisés dans de nombreuses spécialités médicales. L'amélioration de ces biomatériaux vise à augmenter leur ostéointégration et leur bioactivité. Le strontium possédant d'intéressantes capacités de modification de la physiologie osseuse, l'incorporation de ce dernier au sein de phosphates de calcium par substitution ionique pourrait permettre un déplacement de la balance osseuse vers la formation osseuse.Notre travail a permis de démontrer la capacité des particules de phosphates de calcium substitués en strontium à augmenter la prolifération des ostéoblastes en culture et à modifier l'expression et la synthèse des principales protéines impliquées dans la physiologie osseuse (Collagène de type I, Serpine H1, métalloprotéinases matricielles 1 et 2, inhibiteurs tissulaires des MMPs). Par ailleurs, la poudre de phosphates de calcium ne contenant pas de strontium a entrainé une sécrétion accrue de chimiokines pro-inflammatoires (MCP-1 et GRO-?) qui n'a pas été observée pour la poudre substituée. Enfin, des études in-vivo réalisées dans un modèle de défaut osseux murin a permis de démontrer une plus grande résorbabilité de la poudre contenant du strontium et sa plus grande capacité à stimuler la réparation osseuse. / Calcium phosphate are widely used in medicine. Their upgrade tend to enhance their biocompatibility and their bioactivity. Strontium has interesting capability to modify the bone physiologie. Its incorporation in calcium phosphates could lead to modify the bone balance toward osteogenesis.The present work reveal the capacities of such biomaterials to enhance the replication of osteoblasts ant to modify the expression and the synthesis of proteins implicated in the bone balance (type I collagen, serpinH1, Matrix metalloproteinases 1 and 2, tissular inhibitors of MMPs). Moreover, non substituted calcium phosphate powders enhance the expression and synthesis of inflammatory cytokines (MCP-1 and Gro-a). This fact was not observed with the non substituted powder. In-vivo studies on a mouse model permit us to demonstrate the higher resorbability and the higher bone healing capability of the substituted powder.

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