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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

Biologie der Transplantatabstoßung : Nachweis antigenspezifischer T-Lymphozyten und Charakterisierung ihres T-Zellrezeptor-Repertoires / The immunobiology of allograft rejection: Detection of antigen-specific T lymphocytes and characterisation of their T cell receptor repertoire

Kerteß, Tünde January 2007 (has links) (PDF)
Die Organtransplantation stellt ein therapeutisches Verfahren für Patienten mit irreversibel geschädigten Organen dar. Doch weist dieses Behandlungskonzept weiterhin einen wesentlichen Nachteil auf: noch immer wird der langfristige Erfolg der Therapie zu oft durch die so genannte Transplantatabstoßung gefährdet. Hierbei handelt sich um eine vom Organtransplantat ausgelöste Immunantwort, die zu dessen Zerstörung führt. Die derzeit einzige Möglichkeit eine Abstoßung zu verhindern, ist die Unterdrückung des Immunsystems mit so genannten Immunsuppressiva. Auch wenn diese erstmals in den 60er Jahren des 20. Jahrhunderts erfolgreich eingesetzten Medikamente ständig verbessert werden, bleiben die von ihnen ausgelösten Nebenwirkungen weiterhin ein ernstzunehmendes Problem. Sie unterdrücken die gesamte körpereigene Abwehr, was zum Schutz der Organtransplantate vor Abstoßung gewünscht ist, doch fördern sie hierdurch die Entstehung von Tumoren und Infektionen. Bei der Transplantatabstoßung handelt es sich um eine von CD4+ T-Lymphozyten ausgelöste Immunantwort. Diese Lymphozyten werden von allogenen Peptiden, die von Spender-MHC-Molekülen stammen, über den indirekten Weg der Alloantigenerkennung aktiviert. An der Transplantatabstoßung ist zwar eine Vielzahl von Alloantigenen beteiligt, doch ist es möglich, Peptidantigene zu identifizieren, die einen nachweisbaren Effekt auf die Transplantatabstoßung ausüben. So wurde in der eigenen Arbeitsgruppe die für die Abstoßung allogener Organtransplantate beteiligten MHC (RT1u)-Peptidantigene charakterisiert. Insbesondere die Bedeutung des aus 19 Aminosäuren bestehenden allogenen Peptids P1 für die Alloimmunantwort wurde intensiv untersucht. So weisen P1-spezifische T-Lymphozyten ein ausgeprägtes Th1-Cytokin-Muster auf und beschleunigen die Abstoßung von Wistar-Furth-Organtransplantaten in Lewis-Ratten. Das Ziel dieser Arbeit war die Charakterisierung des T-Zellrezeptor Vb-Repertoires P1-spezifischer T-Lymphozyten mit der Methode des PCR-ELISA. In einem ersten Schritt wurden Thymozyten und T-Lymphozyten unterschiedlicher Lymphknotenstationen untersucht. Thymozyten exprimierten alle 22 TCR Vb-Elemente und einzig TCR Vb14 war überrepräsentiert. Die T-Lymphozyten der cervikalen, mesenterialen, iliakalen und poplitealen Lymphknoten zeigten ebenfalls eine charakteristische Überexpression bestimmter TCR Vb-Elemente. So exprimierten cervikale T-Lymphozyten bevorzugt die TCR Vb-Elemente 2, 6, 8.3 und 16, mesenteriale T-Lymphozyten die TCR Vb-Elemente 2, 4, und 8.1, illiakale T-Lymphozyten die TCR Vb-Elemente 2 und 6 und popliteale T-Lymphozyten die TCR Vb-Elemente 2, 4 und 9. Die Immunisierung mit dem nicht-immunogenen Kontrollpeptid (Autoantigen) Ac führte zu einer leichten Veränderung des T-Zellrezeptor-Repertoires, bei der die TCR Vb-Elemente 14 und 16 überexprimiert waren. Das Adjuvant TiterMax beeinflusste kaum das TCR Vb-Repertoire. Die Immunisierung mit dem allogenen Peptid P1 führte zu einer eindeutigen Beeinflussung des T-Zellrezeptor-Repertoires. Popliteale T-Lymphozyten, die 7 Tage nach Immunisierung analysiert wurden, zeigten ein Repertoire, bei dem die TCR Vb-Elemente 15, 16, 17 und 20 überexprimiert waren. Dieses Repertoire war am Tag 3 nach Immunisierung noch nicht so ausgebildet. Wurden die antigenspezifischen T-Lymphozyten nach ihrer Isolierung mit P1 in vitro restimuliert, so waren in diesem T-Zellrezeptor-Repertoire die TCR Vb-Elemente 8.3, 15, 16 und 20 überexprimiert. Zum Vergleich: in naiven T-Lymphozyten waren die Vb-Elemente 2, 4 und 9 überexprimiert. Damit war es zu einer deutlichen Verschiebung im T-Zellrezeptor-Repertoire antigenspezifischer T-Lymphozyten gekommen, die auf das Peptidantigen P1 zurückzuführen ist. Mit der Methode des PCR-ELISA wurde das T-Zellrezeptor-Repertoire antigenspezifischer T-Lymphozyten bestimmt. Hiermit sind wesentliche Voraussetzungen geschaffen worden, um T-Zellklone zu etablieren und ihre Bedeutung für die Transplantatabstoßung genauer zu untersuchen. / Organ transplantation is an important medical therapy for patients with irreversibly damaged organs. However, this therapeutic intervention has a great disadvantage because the long-term success of organ allografts is still too often endangered by the so called allograft rejection, an immune response directed to the allograft and leading to its destruction. The major approach for the prevention and management of allograft rejection is to suppress the immune system with immunosuppressive agents. These agents were introduced into transplantation medicine in the 1960s and since that time they have been continually improved. However, their side effects remain a seriousness problem because the suppression of the immune defence inhibits the allograft rejection on the one hand but causes infections and increases tumour incidence on the other hand. The allograft rejection is mediated by CD4+ T lymphocytes and the responsible antigens recognized by them are allogenic peptides processed from donor MHC molecules. Although a large number of allgenenic peptides are involved in allograft rejection, it is possible to identify certain peptide antigens involved in allograft rejection. In our group allogeneic peptides from MHC class I molecules from Wistar Furth rats were investigated. The significance of the allogeneic peptide P1, consisting of 19 amino acids, in inducing allograft rejection was analysed in detail. P1-specific T lymphocytes demonstrated a Th1-cytokine dominated profile and accelerated the rejection of allografts in Lewis rats donated by Wistar Furth rats. The aim of this study was to characterise the T cell receptor (TCR) Vb repertoire of P1-specific T lymphocytes with the PCR-ELISA technique. First, thymocytes and T lymphocytes from different lymph nodes were analysed. Thymocytes expressed all 22 TCR Vb elements and only TCR Vb14 was overrepresented. The T lymphocytes of cervical, mesenteric, iliacal und popliteal lymph nodes also demonstrated a certain repertoire of overrepresented TCR Vb elements. In cervical T lymphocytes the expression levels of the TCR Vb elements 2, 6, 8.3 and 16 were increased; in mesenteric T lymphocytes the TCR Vb elements 2, 4 and 8.1; in illiacal T lymphocytes the TCR Vb elements 2 and 6; and in popliteal T lymphocytes the TCR Vb elements 2, 4 and 9. The immunisation with the autoantigen Ac led to a small variation of the TCR Vb repertoire and the TCR Vb elements 14 and 16 were overrepresented. The adjuvant TiterMax did not influence the TCR Vb repertoire. In contrast, the immunisation with the allogeneic peptide P1 clearly influenced the T cell receptor repertoire. Popliteal T lymphocytes analysed 7 days after immunisation demonstrated a TCR Vb repertoire where the TCR Vb elements 15, 16, 17 und 20 were overrepresented. On day 3 after immunisation this repertoire was not yet clearly developed. In P1-specific T lymphocytes restimulated in vitro the expression levels of the TCR Vb elements 8.3, 15, 16 and 20 were increased. In comparison, in naïve T lymphocytes the TCR Vb elements 2, 4 and 9 were overrepresented. These results underline that the immunisation with peptide P1 induces a characteristic TCR Vb repertoire. The TCR Vb repertoire of P1-specific T lymphocytes was analysed with the PCR-ELISA technique. The determination of the T cell receptor repertoire is a prerequisite to establish T cell clones and to analyse their involvement in allograft rejection.
282

Pricing models for inflation linked derivatives in an illiquid market

Takadong, Thibaut Zafack 15 September 2009 (has links)
Recent nancial crises have highlighted the sensitivity and vulnerability of nancial markets to in ation, which reduces the value of money and a ects the net returns of nancial instruments. In response to this, investors who are concerned with maintaining their investment's purchasing power rather than its market value are resorting to in ation linked (IL) products to hedge their in ation risk. Consequently, the in ation market has been rapidly growing for the last decade and has further great potential growth worldwide. It is highly probable that in ation linked derivatives will eventually be as common as conventional products. Another cause of the in ation market boost is the growing extension of the time frame of nancial transactions, which has generated an increase in in ation expectation; since 1980 the average time to maturity of long-dated transactions went from one decade to three decades. This is, in part, due to the ageing population in the developed world. This research investigates some alternative models in order to improve the match between model prices and observed prices in the American and South African in ation markets. It takes into account the relative illiquidity of IL products. The main tools used are L evy distributions, macroeconomic factors, no-arbitrage and pricing kernel models. L evy processes can replicate the behaviour of the return innovations of a wide range of nancial securities. Adding a stochastic time change to the L evy process randomises the market clock, thus generating stochastic volatilities, higher stochastic return moments and eventually stochastic skewness. These are observed stylised facts most conventional models do not achieve. Moreover, in contrast to the hidden factor approach, each L evy process component and its stochastic time change can readily be assigned an economic meaning. This explicit economic mapping facilitates the interpretation of current models and provides a more intuitive approach to building new models that capture other observed behaviours. Finally, L evy processes also provide tractable formulas for derivative pricing and market estimations. In general, in ation is a consequence of macroeconomic factors. Exogenous dynamics of the most signi cant of these factors are used to deduce the endogenous in ation dynamics in some of the considered models. In these cases, the calibration of the pricing kernel models requires little historical data on IL derivatives. In fact, the required macroeconomic historical data is easily available because of the current national and international legislation.
283

"Pesquisa do anticorpo antitransglutaminase tissular avaliando as interações da transglutaminase com a fibronectina e comparação com os resultados de dois ensaios comerciais" / Standardization of anti-tissue transglutaminase antibody detection and assessment of transglutaminase interactions with fibronectin : comparison of the results with two commercially available essays

Lemos, Clarice Pires Abrantes 24 August 2005 (has links)
Os objetivos desse estudo foram: 1) Padronizar a pesquisa do anti-tTg, comparando-o com o anticorpo antiendomísio (AAE) e 2) Avaliar as interações da tTg com a fibronectina. 49 celíacos e 124 controles com AAE negativo foram avaliados. O AAE foi pesquisado por imunofluorescência indireta e a reatividade contra a tTg e a fibronectina por ELISA in house e com kits comerciais. O antitTg foi positivo em 46,9% e 100% dos celíacos com o ELISA in house e com kits comerciais, respectivamente. A adição de fibronectina não melhorou a sensibilidade do ELISA. Em conclusão: a detecção do antitTg por ELISA apresenta percentual elevado de falso-positivos, não podendo substituir a pesquisa do AAE / The aims of the current study were: to standardize the detection of anti-tTg antibodies, comparing them with antiendomysial antibodies (EMA) and to assess the interaction of tTg with fibronectin. 49 celiac patients and 124 controls were enrolled. EMA was detected by indirect immunofluorescence reaction and tTg and fibronectin reactivity by in house ELISA and with commercially available kits. Seropositivity to anti-tTG was found in 46.9% and 100% of patients by the in house technique and by commercial kits, respectively. Fibronectin addition did not improve the ELISA sensibility. In conclusion, ELISA for anti-tTG detection has a high rate of false positive results and does not replace EMA
284

Mutação no gene ACSL4 (acyl-CoA synthetase long-chain family member 4) como causa de deficiência mental de herança ligada ao X / Mutation in the ACSL4 (acyl-CoA synthetase long-chain family member 4) as the cause of X linked mental retardation

Reis, Sarita Badiglian Ascenço 30 September 2009 (has links)
Estudamos uma família com cinco homens (dois falecidos) afetados por deficiência mental (DM) não-sindrômica em duas gerações, num padrão de herança ligada ao cromossomo X. A análise do padrão de inativação do cromossomo X, com base na metilação do gene AR, evidenciou que a mulher portadora obrigatória tinha desvio completo de inativação nos leucócitos, uma característica freqüente em portadoras de mutações do cromossomo X relacionadas com DM. Para o mapeamento da DM, genotipamos 28 locos de microssatélites ao longo do cromossomo X e delimitamos um segmento de cerca de 32 Mb, entre os marcadores DXS986 e DXS8067, compartilhado pelos afetados e pela portadora obrigatória, mas não pelo homem normal ou pelas possíveis portadoras que não tinham desvio do padrão de inativação do cromossomo X. Na busca do gene mutado, analisamos, por seqüenciamento direto, genes mapeados no intervalo compartilhado e já relacionados a DM ou que tivessem expressão em cérebro e leucócitos. Nos afetados e na portadora obrigatória, encontramos a mutação c.845C→T no gene ACSL4, que resulta na substituição do aminoácido histidina, conservado na família de sintetases de acil-CoA humanas e em diversos outros organismos, por tirosina (p.H323Y da isoforma cérebro-específica). Tratando-se de mutação que altera um aminoácido evolutivamente conservado em gene já relacionado com DM, que segregava com a DM na família, não tendo sido encontrada em amostra controle de 160 indivíduos do sexo masculino, concluímos que era a causa da DM na família. Mutações de ponto no gene ACSL4 foram relacionadas com a DM não sindrômica em três famílias descritas na literatura. O gene ACSL4 codifica a acil-coA sintetase 4 da família das sintetases de cadeia longa, que catalisa a formação de ésteres acil-coA a partir de ácidos graxos de cadeia longa. Sua expressão já foi documentada em vários tecidos, incluindo o cérebro e dados recentes mostraram que a proteína é essencial para a formação normal de espinhos dendríticos. A nova mutação do gene ACSL4 que descrevemos como causa de DM vem reforçar a relação alterações desse gene e a DM de herança ligada ao X. O padrão de inativação do X totalmente desviado foi mais uma vez observado em mulher portadora da mutação, indicando a importância da expressão desse gene em leucócitos. A presença de dificuldades de aprendizado na portadora da mutação concorda com o observado nas três famílias da literatura em que o estudo das portadoras foi relatado, indicando o efeito de mutações do gene ACSL4 sobre a função intelectual mesmo em heterozigose. A ausência de correlação entre o padrão de inativação do cromossomo X em células do sangue periférico e o comprometimento intelectual foi confirmada. Na família estudada, a identificação da mutação permitiu o aconselhamento genético. / We studied a family with five men (two of them deceased) affected by nonsyndromic mental retardation in two generations, in a pattern of X-linked inheritance (MRX). The study aimed at identifying the causative mutation. The obligate female carrier showed completely skewed inactivation of the X chromosome, based on the methylation status of the AR gene in peripheral blood in leukocytes, a common feature in carriers of X-linked mutations that cause mental retardation. We genotyped 28 microsatellite loci mapped throughout the X chromosome and delimited a 32 Mb segment, between markers DXS986 and DXS8067, that was shared by the affected males and obligate carrier, but was not present in a normal man or in two women who did not show skewed X-inactivation. We searched for the causative mutation by sequencing genes mapped to this candidate interval that had been associated with MR and/or were expressed in brain and leukocytes. In the affected men and obligate carrier, we found a c.845C→T mutation in the ACSL4 gene, resulting in the amino acid tyrosine substituting for a histidine (p.H323Y in brain isoform), which is conserved in the acyl-CoA synthetase family in humans and others organisms. This mutation was not found in a control sample of 160 men. Previously, point mutations in the ACSL4 gene had been identified as the cause of MRX in three families. ACSL4 encodes the acyl-CoA synthetase long-chain family member 4, which catalyzes the formation of acyl-CoA esters from long-chain fatty acids. It is expressed in several tissues, and in brain it is essential for the normal formation of dendritic spines. The novel mutation here described confirmed the causal association of ACSL4 mutations with non-syndromic mental retardation. The completely skewed Xinactivation, also observed in the previously described carriers, supported a functional role for this gene in peripheral blood leukocytes. The intellectual impairment present in the carrier in the family here reported is in accordance with previous findings pointing to the effect on intellectual abilities of ACSL4 mutations in heterozygosis. The absence of correlation between the pattern of X-inactivation in leukocytes and mental status was confirmed.
285

Dosagens sanguíneas de ocitocina por enzimoimunoensaio após diferentes regimes de infusão de ocitocina em gestantes submetidas à cesariana eletiva com raquianestesia / Oxytocin blood levels following different regimens of oxytocin administration in elective cesarean delivery

Yamaguchi, Eduardo Tsuyoshi 26 April 2011 (has links)
INTRODUÇÃO: Apesar de ser a droga de primeira escolha na prevenção da hemorragia pós-parto, o uso da ocitocina em cesarianas permanece empírico. O objetivo deste estudo foi dosar a ocitocina sérica após a administração profilática de diferentes regimes de ocitocina em pacientes submetidas à cesariana eletiva. MÉTODOS: 30 pacientes que se apresentaram para cesariana eletiva foram randomizadas para receber ocitocina intravenosa, após o clampeamento do cordão umbilical, nos seguintes grupos: G1 (n=9): 10 UI de ocitocina infundidas em 30 minutos (0,33 UI/min), G2 (n=11): 10 UI de ocitocina infundidas em 3 minutos e 45 segundos (2,67 UI/min) e G3 (n=10): 80 UI de ocitocina infundidas em 30 minutos (2,67 UI/min). Este estudo foi encoberto para as pacientes e para os cirurgiões. A avaliação do tono uterino foi realizada pela equipe cirúrgica e a dosagem da concentração sérica de ocitocina foi feita pela técnica de enzimoimunoensaio (ELISA), antes da anestesia (T0) e nos tempos 5 (T5), 30 (T30) e 60 (T60) minutos após o início da infusão da ocitocina. RESULTADOS: Os níveis de ocitocina sérica (média ± erro padrão, ng/mL) foram semelhantes entre os grupos em T0 (0,062 ± 0,021; 0,039 ± 0,019 e 0,067 ± 0,041; respectivamente, p = 0,76) e em T60 (0,648 ± 0,257; 0,356 ± 0,257 e 0,683 ± 0,257; respectivamente, p = 0,58). G3 apresentou níveis maiores de ocitocina que G1 em T5 (3,651 ± 0,741 versus 0,709 ± 0,268; p = 0,01). Em T30, G3 apresentou níveis de ocitocina sérica maiores que G1 (6,190 ± 1,195 versus 1,174 ± 0,375; p < 0,01) e, também, que G2 (6,190 ± 1,195 versus 0,411 ± 0,206; p < 0,01). Os parâmetros hemodinâmicos foram semelhantes entre os grupos. O tono uterino foi considerado satisfatório em todos os intervalos estudados e não houve a necessidade de utilização de uterotônico complementar. CONCLUSÃO: Foram demonstradas dosagens séricas de ocitocina por ELISA em gestantes submetidas à cesariana eletiva. A administração de 80 UI de ocitocina em 30 minutos resulta em níveis séricos de ocitocina maiores que os outros dois métodos de administração aos 5 e 30 minutos, porém, estas concentrações não diferem aos 60 minutos / BACKGROUND: The use of oxytocin to prevent postpartum hemorrhage after elective cesarean delivery still remains empirical. The purpose of this study was to determine oxytocin serum levels following differents regimens of prophylactic oxytocin administration in pregnant women undergoing elective cesarean delivery. METHODS: 30 healthy pregnant patients were randomized to receive intravenous oxytocin, after clamping of the umbilical cord, into the following groups: G1 (n=9), 10 IU of oxytocin infused over 30 minutes (0.33 IU/min); G2 (n=11), 10 IU of oxytocin infused over 3 minutes and 45 seconds (2.67 IU/min) and G3 (n=10), 80 IU of oxytocin infused over 30 minutes (2.67 IU/min). Both patient and surgeon were blinded to the study group allocation. Uterine tone was assessed by palpation by the surgeon. Serum oxytocin concentration was determined by enzyme immunoassay (EIA) before anesthesia (T0) and at 5 (T5), 30 (T30) and 60 (T60) minutes following the start of oxytocin infusion. RESULTS: Serum oxytocin levels (mean ± standard error, ng/mL) were similar in the groups at T0 (0.062 ± 0.021, 0.039 ± 0.019 and 0.067 ± 0.041, respectively, P = 0.76), and T60 (0.648 ± 0.257, 0.356 ± 0.257 and 0.683 ± 0.257, respectively, P = 0.58). G3 presented higher serum oxytocin than G1 at T5 (3.651 ± 0.741 versus 0.709 ± 0.268, P = 0.01). At T30, serum oxytocin levels of G3 were higher than G1 (6.190 ± 1.195 versus 1.174 ± 0.375, P < 0.01) and also than G2 (6.190 ± 1.195 versus 0.411 ± 0.206, P < 0.01). Hemodynamic data were similar in all groups. Uterine tone was considered satisfactory in all intervals studied and no additional uterotonic agent was needed. CONCLUSION: We demonstrate serum oxytocin determinations by EIA in healthy pregnant women presented for elective cesarean delivery. Administering 80 IU in 30 min results in higher serum oxytocin levels at 5 and 30 min than the other two methods of oxytocin administration, but the concentrations did not differ at 60 min
286

\"Padronização e desenvolvimento de reagentes imunoenzimáticos para pesquisa de ciprofloxacina em produtos de origem animal\" / Standardization and development of immunoenzymatics reagents for ciprofloxacin in animal products

Gobbo, Sarita Priscila 31 July 2006 (has links)
O crescimento cada vez maior da industrialização e a existência de um mercado globalizado vêm exigindo dos produtores rurais à utilização de modernas tecnologias ligadas à produção animal. O baixo custo de produção e o aumento da qualidade do produto final gerado têm sido a grande meta dos pecuaristas e centros de pesquisa voltados à agropecuária. Devido à necessidade de aumento na produção, propriedades agropecuárias têm recorrido ao uso de todo e qualquer recurso disponível que possa promover melhorias na atividade produtiva.O uso indiscriminado dos antimicrobianos com a intenção de aumentar a produção animal pode resultar em concentrações residuais nos produtos como carne, ovos e leite acima das doses aceitáveis para o consumo humano. Inicialmente, os antibióticos eram usados como medida terapêutica, mas com o avanço do conhecimento e desenvolvimento de novos compostos, passaram a ser utilizados também como medida preventiva e como promotores do crescimento.O que se deve questionar não é a presença destes resíduos, mas sim o tipo e as concentrações dos mesmos. De fato, as modernas tecnologias analíticas têm permitido a detecção de partes por bilhão de substâncias químicas, componentes ou metabólitos de medicamentos de uso veterinário em alimentos e, nestas quantidades, dificilmente elas representariam perigo à saúde dos consumidores. Portanto, há necessidade de se estabelecer metodologias analíticas mais eficientes que possam auxiliar os órgãos de fiscalização da agricultura no controle do uso desses antimicrobianos na produção animal. Assim como auxiliar no controle de qualidade, principalmente em indústrias exportadoras que almejam expansão de mercado, onde essa prática é quase uma imposição no contexto do comércio internacional de produtos pecuários \"in natura\" e processados. Devido a essas necessidades, o objetivo do presente foi padronizar e desenvolver reagentes imunoenzimáticos para a pesquisa da ciprofloxacina em produtos de origem animal. Os resultados obtidos no desenvolvimento desses imunoreagentes foram positivos quando correlacionado (r2 = 0,9588) com o kit referência RIDASCREEN® Enro/Cipro da R-Biopharm. Diante disso, é possível concluir que o Brasil possui infra-estrutura adequada para padronizar esses testes rápidos, evitando com isso um grande gasto na importação desses kits / The growth each time higher of industrialization and the existence of a global market forces the rural producers to use modern technologies related to animal production. The low production cost and the increasing of obtained final product quality have been the great aim of cattle farmers and cattle farming research centers. Due to the necessity of increasing the production, rural properties have required the use of any available source able to promote better productive activities. The indiscriminated antibiotics use aiming to increase animal production may result in residual concentrations found in products such as meat, eggs and milk over acceptable doses to the human consumption. Firstly, antibiotics were used as therapeutic prescriptions although the advances on knowledge and development of new compounds were also used as a preventive way and as growth promoters. What must be questionable its not the presence of these residuals but surely what kind of residual and their concentrations. In fact, the modern analytic technologies make possible the detection of parts per billions (ppb) of chemical substances, compounds or medicine metabolites of veterinary use in food and in these quantities, hardly they would be dangerous to the consumer health. However, it\'s necessary to establish more efficient analytic methodologies to help on agriculture supervising organs in the control of these antibiotics use in the animal production. Thus, how to help in the quality control, mainly in industries that export to get the market expansion, where this activity is almost an imposition at the international trade context of farming products \"in natura\" and industrialized ones. Due to these necessities, the goal of our present work was to standard and develop immunoenzymatics reagents to the ciprofloxacin researching from animal products. The results obtained on development of these immunoreagents were positive when correlated (r2= 0,9588) to the kit RIPASCREEN® Enro/Cipro from R-Biopharm reference. At the light of these knowledge, it?s possible to conclude that Brazil has adequate proper-structure to standardize these quick tests, to avoid in this way a high cost to import these kits.
287

Synthesis of Rigidly Linked Polychromophores for Intramolecular Energy Transfer Study

Zhang, Rong 09 January 2002 (has links)
Intramolecular energy transfer is reviewed from several perspectives, such as the generally accepted mechanism and molecular structure dependence. Some unique molecules with bichromophores or trichromophores linked by rigid bridges were designed to serve as models for studying the intramolecular triplet-triplet energy transfer. Bichromophoric molecules containing an anthracene donor and phenanthrene or diphenylpolyene acceptors linked by linearly fused norbornane units were synthesized. Approaches to the analogous compounds with anthracene as the donor and benzophenone or p-terphenyl as acceptors are presented. Synthetic approaches to cis, exo-1, 4-dihydro-1, 4-methanotriphenylene, a precursor to the polynorbornyl-linked polychromophore, and trichromophoric compounds linked by adamantane spacers were explored.
288

Hledání a vytváření relací mezi sloupci v CSV souborech s využitím Linked Dat / Discovering and Creating Relations among CSV Columns Using Linked Data Knowledge Bases

Brodec, Václav January 2019 (has links)
A large amount of data produced by governmental organizations is accessible in the form of tables encoded as CSV files. Semantic table interpretation (STI) strives to transform them into linked data in order to make them more useful. As significant portion of the tabular data is of statistical nature, and therefore comprises predominantly of numeric values, it is paramount to possess effective means for interpreting relations between the entities and their numeric properties as captured in the tables. As the current general-purpose STI tools infer the annotations of the columns almost exclusively from numeric objects of RDF triples already present in the linked data knowledge bases, they are unable to handle unknown input values. This leaves them with weak evidence for their suggestions. On the other hand, known techniques focusing on the numeric values also have their downsides. Either their background knowledge representation is built in a top-down manner from general knowledge bases, which do not reflect the domain of input and in turn do not contain the values in a recognizable form. Or they do not make use of context provided by the general STI tools. This causes them to mismatch annotations of columns consisting from similar values, but of entirely different meaning. This thesis addresses the...
289

Integrating Linked Data search results using statistical relational learning approaches

Al Shekaili, Dhahi January 2017 (has links)
Linked Data (LD) follows the web in providing low barriers to publication, and in deploying web-scale keyword search as a central way of identifying relevant data. As in the web, searchesinitially identify results in broadly the form in which they were published, and the published form may be provided to the user as the result of a search. This will be satisfactory in some cases, but the diversity of publishers means that the results of the search may be obtained from many different sources, and described in many different ways. As such, there seems to bean opportunity to add value to search results by providing userswith an integrated representation that brings together features from different sources. This involves an on-the-fly and automated data integration process being applied to search results, which raises the question as to what technologies might bemost suitable for supporting the integration of LD searchresults. In this thesis we take the view that the problem of integrating LD search results is best approached by assimilating different forms ofevidence that support the integration process. In particular, thisdissertation shows how Statistical Relational Learning (SRL) formalisms (viz., Markov Logic Networks (MLN) and Probabilistic Soft Logic (PSL)) can beexploited to assimilate different sources of evidence in a principledway and to beneficial effect for users. Specifically, in this dissertation weconsider syntactic evidence derived from LD search results and from matching algorithms, semantic evidence derived from LD vocabularies, and user evidence,in the form of feedback. This dissertation makes the following key contributions: (i) a characterisation of key features of LD search results that are relevant to their integration, and a description of some initial experiences in the use of MLN for interpreting search results; (ii)a PSL rule-base that models the uniform assimilation of diverse kinds of evidence;(iii) an empirical evaluation of how the contributed MLN and PSL approaches perform in terms of their ability to infer a structure for integrating LD search results;and (iv) concrete examples of how populating such inferred structures for presentation to the end user is beneficial, as well as guiding the collection of feedbackwhose assimilation further improves search results presentation.
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In vitro investigation of the role of human cytomegalovirus glycoprotein polymorphisms in disease pathogenesis

Abdulhakim, Jawaher January 2018 (has links)
HCMV is a common viral pathogen that infects most of the world's population by early adulthood. It is typically asymptomatic in immunologically healthy individuals but causes severe disease in immunocompromised patients and congenitally infected infants. HCMV glycoproteins are highly polymorphic, and various types of associations have been suggested between glycoprotein types and the pathogenicity of the virus. Several studies on viruses other than HCMV have related the glycosylation of the viral glycoproteins to virulence. This project aimed to determine whether there is a robust relationship between the individual glycoprotein sequence and its glycosylation, how this influences the growth characteristic of the virus and whether this is related to its pathogenicity. Glycosylation patterns of 89 clinical specimens of different infection categories and specimen types were correlated with genetic sequence alterations of the virus glycoproteins (gB, gH, gL, gM, gN, gO), followed by determining whether mutation results in specific changes in glycosylation. The aim was approached using a cell culture model and a quantitative lectin-based assay (ELLA). A significantly increased glycosylation level for the following genotypes: mixed gH, gN4a, gO4, mixed gL was detected. Whereas a decreased pattern was found to be associated with gH1, gH2, gN3a, gO1a and gL2 genotypes (P < 0.05). Glycoproteins of strains isolated from respiratory specimens were significantly highly glycosylated compared to the blood and urine samples, and from blood specimens compared to the urine samples (P < 0.05). Furthermore, strains from congenitally infected infants and urine samples had a significantly higher growth rate than others tested. No direct association between the virus growth and its virulence was found. These findings demonstrate that glycosylation of glycoproteins in HCMV is affected by the glycoprotein polymorphisms and signifies a potentially important mechanism for avoidance of antibody-mediated neutralization, which, in turn, facilitates HCMV pathogenicity. This phenomenon requires further study and may have application for the selection of novel targets for diagnosis, vaccine development and other preventive measures to combat diseases caused by this virus.

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