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Marsh, Maija. "The effect of behaviour in disease transmission : Understanding RHDV Dynamics in Austrlian rabbit populations." Thesis, University of York, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520028.
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Fages, Marie-Philippe Bertagnoli Stéphane. "Identification d'un nouveau variant apathogène du virus de la maladie hémorragique virale du lapin (RHDV)." [S.l.] : [s.n.], 2007. http://oatao.univ-toulouse.fr/1755/1/debouch_1755.pdf.
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Joubert, Pascale. "Etude des mécanismes de maturation de la polyprotéine du virus de la maladie hémorragique du lapin (RHDV)." Tours, 2000. http://www.theses.fr/2000TOUR4009.
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Le rabbit haemorrhagic disease virus (RHDV) est responsable d'hépatites fulminantes et peut tuer 90% d'une population de lapins en moins de 48h. Le RHDV est un calicivirus du genre lagovirus. Non enveloppé, il présente un ARN simple brin de polarité positive de 7,5 KB pour génome. Cet ARN génomique possède 2 ORF : l'ORF1 codant pour une polyprotéine de 257 KDA et l'ORF2 codant pour la protéine structurale VP10. Cette polyprotéine présente 6 protéines non structurales dont l'hélicase, la protéase et l'ARN polymérase et 2 protéines structurales, la VPG et la protéine de capside. La protéase, apparentée au groupe des chymotrypsine-like cystéine protéases, semble être la seule protéine virale impliquée dans le processus de maturation. Les études réalisées jusqu'alors ont permis de montrer que le processus de maturation se déroulait en au moins 2 étapes et conduisait à la libération de 8 protéines impliquant 7 sites de clivage protéolytique. Trois sites spécifiquement clivés par la protéase avaient été décrits auparavant par différents auteurs : EG (718-719), EG (1108-1109) et EG (1767-1768) et, aussi, un 4ème site suspecté, le site ET (1251-1252). Le virus RHDV ne se multipliant pas en culture cellulaire, nous avons développé une technique basée sur l'utilisation du gène de la luciférase comme gène rapporteur. Cette technique originale a permis de confirmer les 3 sites EG déjà décrits, d'identifier le quatrième responsable de la maturation primiaire, le site EG (143-144) et 2 sites faiblement clivés EG (339-340) et EG (776-777). Ces 6 sites de clivage s'intègrent parfaitement dans le modèle de maturation proposé par König et al. (1998). Ce travail de thèse permet de comparer pour la première fois l'activité protéolytique de la protéase courte (1109-1251) avec celle du précurseur P72 (protéase-polymérase). La protéase courte est capable d'une activité protéolytique trans et cis au niveau de 4 sites cités précédemment. Cependant, le précurseur P72 présente la meilleure efficacité de clivage et semble responsable de la maturation complète de la polyprotéine du RHDVNo summary available
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Müller, Claudia [Verfasser], and Gerd [Akademischer Betreuer] Sutter. "A new RHDV-2 vaccine based on recombinant baculovirus : generation and characterization of induced immunity in rabbits / Claudia Müller ; Betreuer: Gerd Sutter." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1158496206/34.
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Guillon, Patrice. "Antigènes tissulaires de groupe sanguin ABH acteurs de la protection innée antivirale : exemples des Calicivirus (NV et RHDV) et du Coronavirus SRAS-CoV." Nantes, 2008. https://archive.bu.univ-nantes.fr/pollux/show/show?id=d7627fae-7b41-4797-ad78-963bffc5f6c7.
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Les antigènes tissulaires de groupe sanguin sont des motifs glycanniques présents sur les cellules épithéliales ou dans les sécrétions et également trouvés sur les érythrocytes de certains primates. Leur synthèse nécessite l’action de glycosyltransférases codées par les gènes Fut1, Fut2, Sec1 ou Abo. Ils servent de ligands à diverses souches de Calicivirus du genre norovirus responsables de gastro-entérites chez l’homme, le polymorphisme aux loci FUT2 et ABO contrôlant la sensibilité à ces virus. Dans ce travail nous montrons que le lait maternel contient des molécules de type mucine qui inhibent la fixation de la souche NV. L’inhibition est dépendante de la présence d’un allèle FUT2 permettant la synthèse de glycannes α1,2fucosylés. Un autre Calicivirus, le RHDV, responsable de la maladie hémorragique du lapin (RHD), se fixe sur un glycanne α1,2fucosylé. Nous avons observé qu’il existe des lapins sauvages présentant un déficit d’expression de ce ligand dont la fréquence dans les populations est augmentée à la suite d’épidémies de RHD. Un allèle du gène Sec1 a pu être associé à la survie des animaux, suggérant une sélection par le virus. La protéine d’enveloppe du Coronavirus du SRAS lui permet de se fixer sur son récepteur cellulaire et peut porter des antigènes ABH. Des anticorps anti-A du plasma de sujets O inhibent la fixation de cette protéine sur son récepteur lorsqu’elle est synthétisée dans des cellules A, expliquant la plus grande sensibilité des individus A (ou B) au SRAS. Ainsi les antigènes de groupes sanguins tissulaires pourraient contribuer à la protection innée antivirale par des mécanismes complémentaires, expliquant leur maintien au cours de l’évolutionHisto-blood group antigens are glycan motifs present on mammalian epithelial surfaces and in secretion. They are also found on erythrocytes from apes. Their synthesis requires glycosyltransferases encoded by the Futi, Fut2, Seel and Abo genes. They are ligands for various Calicivirus strains of the norovirus genus which cause gastroenteritis in humans and polymorphisms at the FUT2 and ABO loci control sensitivity to these viruses. In this work, we show that maternal milk contains mucin-type molecules that inhibit NV strain binding to its α1,2fucosylated ligand. The inhibition depends upon a FUT2 allele that allows α1,2fucosylation. Another Calicivirus, RHDV, responsible for the rabbit hemorrhagic disease, binds to an α1,2fucosylated ligand. We observed that there exist wild rabbits presenting a deficit of expression of the ligand. Their frequency is increased following RHD outbreaks. Moreover, a Seel allele has been associated with the survival of animals, suggesting a selection by the virus. The enveloppe protein of the SARS Coronavirus allows binding to its cellular receptor and may carry ABH antigens. We show that natural antibodies from the plasma of 0 individuals inhibit attachment of this protein to its receptor when it is synthesized in A cells. This may explain the higher sensitivity of A (or B) individuals to SARS. Overall, the results are discussed to suggest that histo-blood group antigens could contribute to innate antivirus protection by various complementary mechanisms, which could explain why they have been maintained throughout mammalian evolution
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Müller, Alexandra. "Virus-host adatation and co-evolution of myxoma virus (MV) and rabbit haemorrhagic disease virus (RHDV) in their natural host, the wild rabbit (oryctolagus cuniculus)." Doctoral thesis, Instituto de Ciências Biomédicas Abel Salazar, 2009. http://hdl.handle.net/10216/45396.
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Müller, Alexandra. "Virus-host adatation and co-evolution of myxoma virus (MV) and rabbit haemorrhagic disease virus (RHDV) in their natural host, the wild rabbit (oryctolagus cuniculus)." Tese, Instituto de Ciências Biomédicas Abel Salazar, 2009. http://hdl.handle.net/10216/45396.
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Le, Gall Ghislaine. "Calicivirus des lagomorphes : détermination de la séquence nucléotidique de l'EBHSV (european brown hare syndrome virus) : épidémiologie moléculaire des virus EBHSV et RHDV(rabbit haemorrhagic disease virus)." Brest, 1997. http://www.theses.fr/1997BRES3103.
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Laurent, Sylvie. "Étude de la protéine de capside des calicivirus des lagomorphes RHDV (Rabbit Haemorrhagic Disease Virus) et EBHSV (European Brown Hare Syndrome Virus) : antigénicité, vaccination et assemblage." Compiègne, 1997. http://www.theses.fr/1997COMP1029.
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Les virus RHDV (Rabbit Haemorrhagic Disease Virus) et EBHSV (European Brown Hare Syndrome Virus) ont été décrits pour la première fois sur le continent européen au début des années 1980. Ces deux virus, responsables d'hépatites nécrosantes, sont capables de tuer 90% d'une population de lapins ou de lièvres en moins 48h. Ils ont été affiliés récemment à la famille des Caliciviridae. Les calicivirus possèdent un génome à ARN simple brin de polarité positive et sont composés d'une simple capside constituée d'une unique protéine structurale de 60KDa. Les protéines de capside de RHDV et EBHSV ont été exprimées dans le système baculovirus/cellules d'insecte. Les protéines de capside recombinantes produites en quantité massive ont été retrouvées dans le surnageant de culture sous la forme de pseudo-particules, présentant les mêmes caractéristiques morphologiques et antigéniques que les virions infectieux. Les particules recombinantes de RHDV utilisées dans des tests de vaccination ont conféré une protection équivalente à celle démontrée par les vaccins actuellement commercialisés. L'étude de la séroconversion des lapins vaccinés a mis en évidence le rôle clef de la réponse humorale dans la protection contre la maladie. Ces résultats ont conduit à l'élaboration d'un vaccin recombinant actuellement en cours de développement industriel. L'utilisation des particules recombinantes de RHDV et de EBHSV lors d'études comparatives, réalisées à l'aide de plusieurs anticorps monoclonaux anti-RHDV et anti-EBHSV, ont permis de caractériser les réactions antigéniques croisées entre les deux virus. Ces résultats couplés à ceux de tests de protection croisée ont permis de classer ces deux virus dans deux sérotypes du même sérogroupe au sein de la famille des Caliciviridae. Plusieurs données concernant l'assemblage des calicivirus, obtenues par l'analyse des particules recombinantes en conditions non dénaturantes, ainsi que par l'analyse des séquences peptidiques, sont discutées.
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Rodrigues, Artemis Socorro do Nascimento. "Caracterização molecular dos antigenos RhD, (RhD fraco e RhD parcial) e sua aplicação na pratica transfusional." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310418.
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Orientador: Lilian Maria de CastilhoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: Considerando a imunogenicidade e importância clínica do antígeno RhD bem como o grande número de variantes RhD identificadas, estudos que possam esclarecer sua expressão e mecanismos moleculares envolvidos são importantes para a padronização de técnicas moleculares e sorológicas em diferentes populações. Assim foram nossos objetivos: padronizar técnicas moleculares para realização da genotipagem RHD fraco e determinar sua ocorrência na população brasileira; associar os tipos de RhD fracos encontrados com os haplótipos Rh presentes; e avaliar a aplicação da determinação do antígeno RhD na prática transfusional. Estudamos 503 amostras de DNA de doadores voluntários de sangue fenotipados como RhD ftaco. Destas amostras de DNA estudadas, 415 (82,5%) foram caracterizadas como RhD ftaco, 65 (12,9%) como RhD parcial, 15 (3%) apresentaram associações de RhD parcial e RhD ftaco e 8 (1,6%) foram RhD normal. I Os antígenos RhD fraco tipos 1, 3 e 4 foram os mais fteqüentes em nossa população. Como estes três tipos de RhD fraco não apresentam risco de aloimunização anti-D, pacientes assim classificadospodem ser transfundidos com sangue RhD-positivo. Nossos resultados demonstraram que 12,~A>das amostras fenotipadas como RhD fraco eram na verdade RhD parcial. Os antígenos RhD parciais encontrados em nosso estudo foram D~ DHMi e DVI. Quarenta (7,9%) amostras de DNA foram caracterizadas como D~ 16 (3,2%) como DHMi e 9 (1,8%) como DVI. A caracterização dos antígenos RhD parciais que reagem sorologicamente como RhD ftaco, tais como D DHMi e RhD categoria VI pode ser de grande auxilio na prevenção da aloimunização anti-D em pacientes politransfundidos e gestantes. A freqüência dos antígenos RhD parciais D~ DHMi e DVI encontrada em nossas amostras sugere um elevado risco de aloimunização ao antígeno RhD em pacientes fenotipados como RhD ftaco. - Das 503 amostras estudadas, 15 apresentaram mutações responsáveis pela expressão do antígeno RhD fraco e ao mesmo tempo mutações características de antígenos RhD parciais, ou seja, estas amostras possuíam os antígenos RhD fraco e RhD parcial associados. Estudamos quatro amostras de DNA de pacientes fenotipados como RhD :fraco que apresentavam anti-D. Nosso estudo demonstrou que a aloimunização anti-D nestes pacientes estava relacionada à presença de um antígeno RhD parcial e não a um antígeno RhD :fraco como diagnosticado sorologicamente. Duas amostras foram classificadascomo RhD parcial DAR, 1 como RhD parcial DHMi e 1 como DVI. Os resuhados demonstraram que os tipos de RhD fraco 1, 2, 3 e 4 que foram detectados à TA ou à 3'te e apresentaram grau de aglutinação superior a 1+ na AGH podem ser considerados como RhD positivo, pois não foram associados ao antígeno RhD parcial. Apesar deste trabalho ter sido o único que relacionou os tipos de RhD ftaco com o grau de aglutinação, a literatura revela que ainda não foi demonstrada aloimunização anti-D em pacientes portadores dos antígenos RhD fraco tipos 1,2 e 3. De acordo com os nossos resultados pode-se concluir que: 1. A transfusão com sangue RhD-positivo pode ser recomendada para todos os pacientes que apresentam os tipos do antígeno RhD :ftaco 1, 3 e 4 identificados por técnicas moleculares e para aqueles que apresentarem grau de aglutinação superior a 1+ na fenotipagem RhD. 2. A utilização de métodos de fenotipagem mais sensíveis em combinação com reagentes anti-D de alta afinidade é recomendada na detecção de antígenos RhD ftaco com baixa densidade antigênica em doadores de sangue; 3. Há necessidade da utilização de dois anti-soros monoc1onais (IgM e IgG) na determinação do antígeno RhD :ftacoem pacientes; 4. As genotipagens RHD, RHD ftaco e RHD parcial devem ser rea1i73dasquando os resuhados sorológicos não forem claros ou quando o paciente for politransfundido. 5. A biologia molecular associada à hemaglutinação pode aumentar consideravelmente a segurança transfusional pela mellior caracterização dos antígenos RhD em nossa população
Abstract: The purpose of this study was to characterize by molecular studies theRhD antigens (weak D and partial D) in Brazilian blood donors. DNA samples ftom 503 blood donors phenotyped as weak D were tested by two different sequence-specific primers (pCR-SSP) assays to determine the presence or absence of RHD gene (PCR-SSP intron 4 and exon 10) and to detect the common weak D types. Ofthe 503 weak D samples studied, 415 (82,5%) were identified as weak D, 65 (12,9%) as partial D, 15 (3%) showed association ofweak D and partial D and 8 (1,6%) were normal D. Weak D types 1, 3 and 4 contributed more than 85% of alI molecular weak D types. For these 3 types, D-positive transfusion can be considered safe because no immunization events have been documented yet. These findings show for the first time the frequency of weak D types in Brazilians. Molecular analysis showed that 12,9% of the weak D phenotype samples studied carried a partia! D alIele. The partial Ds found in our study were DAR, DVI and DHMi. Forty (7,9%) DNA samples were characterized as DAR, 16 (3,8%) as DHMi and 9 (1,8%) as DVI. The characterization of the partia! D antigens DAR, DHMi and DVI may avoid alIoimmunization in patients phenotyped as weak D. Fiffeteen patients showed mutations to weak D and partia! D showing that these samples had the weak D and partia! D antigens associated. We also studied 4 DNA samples of patients phenotyped as weak D who had developed anti-D. Our study showed that anti-D alIoimmunization in these patients was associated with the presence of partia! D antigens. Two samples were classified as partia!, D DAR, 1 as DHMi and 1 was DVI.AlI the weak D types identified in our study were associated with the intensity of agglutination obtained at room temperature (RT), 3'fC and AGH. The sensitivity of detecting weak D depends on the anti-D reagent and on the exact conditions of the methods. Our results showed that the weak D types 1, 2, 3 and 4 were frequently detected at RT and 3'fC and therefore could be considered as D-positive for transfusion. According to our results we could recommend the use ofmonoclonal anti-DIgM with high avidity to detect weak D antigen with low antigen density in blood donors and two monoclonals, one IgM and one IgG in combination with AGT to detect the weak D antigen in patients
Doutorado
Ciencias Basicas
Doutor em Clínica Médica
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Axelsson, Lena. "Karakterisering av blodgruppsgenen RHD hos patienter med svagt RhD-antigenuttryck." Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-24168.
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Rh-blodgruppssystemet är mycket komplext med 54 blodgruppsantigen som kodas av två nära varandra belägna gener på kromosom 1 – RHD och RHCE. RHD-genen kodar för RhD-proteinet, ett membranbundet protein på erytrocyter vars antigen utgör de kliniskt viktigaste och mest immunogena efter ABOsystemets, och som kan ge upphov till transfusionskomplikationer och hemolytisk sjukdom hos foster och nyfödda. Vissa individer har varianter av RhD-protein som uttrycks svagare än normalt (”svaga D”), eller där vissa epitoper saknas (”partiella D”), och för vilka serologiska metoder inte kan ge enhetliga resultat. Detta orsakar problem vid blodtransfusion, graviditet och bloddonation, och leder ofta till användning av det redan knappa lagret av RhD-negativa blodenheter för att skydda patienten. I detta projekt har åtta prover med svaga RhD-antigenuttryck sekvenserats med avseende på RHD-genen i syfte att fastställa individernas RhDfenotyp. I sex av proverna hittades sex nukleotidpolymorfismer och två deletioner, som alla är sällsynta men dock är kända sedan tidigare. I två prover kunde inga mutationer i exon eller intilliggande intron påvisas som förklaring till de svaga uttrycken av RhD hos dessa individer.The Rh blood group system is very complex with 54 blood group antigens encoded by two adjacent genes on chromosome 1 – RHD and RHCE. The RHD gene encodes the RhD protein, a membrane bound protein on erythrocytes whose antigens are the most clinically important and immunogenic after those of the ABO system, and which can result in transfusion complications and haemolytic disease of the fetus and newborn. Some individuals have variants of the RhD proteins that are expressed more weakly than normal (“weak D”), or have some of the epitopes missing (“partial D”), and for which serological methods cannot give a uniform result. This provides a problem in blood transfusion, pregnancy, and blood donation, and often results in the use of the already sparse supply of RhDnegative blood units for the safety of the patient. In this project, eight samples with weak RhD antigen expression have been sequenced with regard to the RHD gene in order to determine the RhD phenotype of the individuals. In six of the samples, six single nucleotide polymorphisms and two deletions were found, all of which are rare but are previously known. For two of the samples, no mutations in exons or adjacent introns could be detected to explain the weak expression of RhD in those individuals.
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Castilho, Shirley Lopes de. "Mapeamento das condições necessárias para a incorporação da genotipagem RhDa partir do DNA fetal livre no plasma materno na rotina pré-natal de gestantes RhD-negativo acompanhadas no SUS." Instituto Fernandes Figueira, 2011. https://www.arca.fiocruz.br/handle/icict/6659.
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Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Ensino. Programa de Pós-Graduação em Saúde da Criança e da Mulher. Rio de Janeiro, RJ, Brasil
O desconhecimento do grupo sanguíneo RhD fetal durante o período gestacional faz com que gestantes RhD-negativo tenham o mesmo acompanhamento pré-natal independente do feto ser RhD-positvo ou RhD-negativo. Assim, gestantes sem risco para o desenvolvimento de Doença Hemolítica Perinatal (DHPN) são mantidas no pré-natal de alto risco aumentando a taxa de ocupação destes serviços e dificultando a oferta para aquelas que realmente necessitariam de assistência especializada. Um método atual, não invasivo, a genotipagem RhDa partir do DNA fetal livre no plasma materno permite o conhecimento do grupo sanguíneo fetal antes do nascimento possibilitando excluir do pré-natal de alto risco gestantes com fetos sem risco para a DHPN (fetos RhD-negativos). Este estudo objetiva mapear o Fluxo da assistência pré-natal, em especial de gestantes RhD-negativo, no Município do Rio de Janeiro visando analisar a viabilidade da incorporação da genotipagem RhDa partir do DNA fetal livre no plasma materno na rotina pré-natal de gestantes RhD-negativo acompanhadas no SUS. Esta análise foi realizada aplicando o método de Planejamento Estratégico Situacional (PES) proposto por Carlos Matus. O método PES prevê quatro momentos para o processamento dos problemas. O Momento explicativo prevê o diagnóstico situacional, O momento normativo formula os objetivos e o prazo para executá-los, o Momento estratégico analisa a viabilidade dos planos e os atores envolvidos no processo e o momento operacional estabelece a execução dos planos e a avaliação das mudanças. Concluímos que a implantação da genotipagem RhDfetal utilizando o DNA livre no plasma materno e a PCR em tempo real, no SUS, é factível. O cenário atual é extremamente favorável. A preocupação das três esferas do governo com a assistência integral à saúde materna e infantil promove um leque de investimentos amplos neste segmento. A possível ação conjunta entre o governo e as instituições públicas, com expertise em desenvolvimento de métodos diagnóstico como Biomanguinhos, possibilitaria a implantação desta tecnologia para diferentes segmentos da saúde pública no Brasil.
The lack of knowledge about the Rhblood group during the pregnancy period make the D-negative pregnant women have the same prenatal follow-up whether the fetal blood type isD positive or D-negative. In this way, pregnant women without risk to develop Hemolytic Disease of newborn (HDN) are kept in High Risk Prenatal Care increasing the occupancy rate of the assistance servicesdecreasing the viability for who those really need it. Nowadays a non-invasive method, the RHD genotyping using free-fetal DNA from maternal plasma allows the fetal blood group knowledge before the birth. This makes possible to exclude from High Risk Prenatal Care, pregnant women with fetus without HDN risk. This study aims the understanding of prenatal care flow of D-negative pregnant women in Rio de Janeiro city trying to check the viability of the introduction of RHD genotyping test using free-fetal DNA from maternal plasma in the D-negative pregnant women in prenatal care public service. This analysiswas made using strategic-situational approach of CarlosMatus. There are four (4) moments of strategic planning, according to Carlos Matus.The analytical moment describes the stage of formulation of initial situation (diagnosis), the Normative Moment designs the aims and defines the strategy of action. The Strategic Moment analyzes the actors enrolled in the process and the viability of plans. The Operational Moment establishes the execution of plans and evaluates the changes. In conclusion, the introduction of RHD genotyping test in free-fetal DNA from maternal plasma using real-time PCR, in public services, is factual. Brazil’s Health Ministry is working on improving the public health system. The government issues about full assistance to women and children promote wide investments in this heath area. Actions joining both government and public institutions with expertise as Biomanguinhos would make possible the development of different diagnoses methods in health care in Brazil.
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Bustamante-Gallardo, Pedro. "Molecular studies on Rice hoja blanca virus (RHBV)." Thesis, University of East Anglia, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338096.
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Baldauff, Rachel Michelle. "Interaction of Recombinant Paraoxonase-1 with Reconstituted High-Density Lipoproteins." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1321986125.
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Doyle, Caitlin. "Isolation and characterization of genetic modifiers of Arabidopsis RHD3." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110637.
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AbstractRoot hair cells of Arabidopsis are a model system for investigations of polarized cell expansion. Root hairs are long, cellular extensions, produced by tip growth on trichoblast cells of the root epidermis. Many genes necessary for proper tip growth have been identified in Arabidopsis including RHD3. The Arabidopsis root hair defective3 (rhd3) mutant produces short, misshapen root hairs. RHD3 was cloned as a large GTP binding protein, and recently it was shown to be involved in the formation of the tubular ER network. To date, the role of RHD3 in ER formation and the cause of the defective root hairs in rhd3 mutants are still not clear. To uncover genetic interactions of RHD3, a genetic modifier screen was conducted in an rhd3 mutant background. Through this experiment 10 genetic modifiers of rhd3 were isolated. Characterization of these modifiers, revealed that 9 of them carry single, recessive mutations which, in combination with the rhd3 mutation, disrupt the growth of root hairs. Three of the mutations cause mutant root hair phenotypes without the rhd3 mutation. The remaining mutations fall into two groups; those that appear to be epistatic to mutations in RHD3 and those that are only able to affect root hair development in an rhd3 mutant background. A test for genetic interactions between RHD3 and two known genes, SHV2 and BOT1, was also conducted. The SHV2 gene encodes a GPI-anchored, COBRA-like protein, and mutations in SHV2 impair root hair elongation. Analysis of shv2 rhd3 double mutants, revealed that mutations in SHV2 can synthetically enhance the rhd3 mutant root hair phenotype.BOT1 encodes a Katanin-like, microtubule severing protein. Mutations in BOT1 lead to the growth of ectopic root hairs. Double mutant analysis revealed that mutations in BOT1 can partially suppress the effects of mutations in RHD3 on the growth of root hairs.Résumé Les poils absorbants sont de longues extensions cellulaires produits dans la racine au niveau de la zone pilifère. Le mutant root hair defective3 (rhd3) d'Arabidopsis produit des poils absorbants courts et malformé. RHD3 est une grande protéine de liaison de GTP. Récemment il a été démontré que RHD3 est impliquée dans la formation du réseau tubulaire du réticulum endoplasmique (RE), mais l'implication de RHD3 dans la malformation des poils absorbants reste à élucider. Pour mieux comprendre le rôle de RHD3 lors de l'élongation des poils absorbants, nous avons crée d'autres mutants à partir d'Arabidopsis thaliana rhd3. Ce criblage nous a permis d'identifier 10 nouveaux gènes impliqués dans la croissance de l'apex racinaire, nommés de ren1 à ren10. L'analyse de ces mutants a révélé qu'à l'exception de ren5 les 9 autres mutants sont des mutations ponctuelles récessives qui associées la mutation rhd3 affectent la formation des poils absorbants. Trois de ces mutations (ren6, ren7 et ren9) causent des phénotypes anormaux des poils absorbant en l'absence de la mutation rhd3. Les mutations restantes se répartissent en deux groupes : ren1, ren2 et ren8, qui sont difficile à interpréter et ren3, ren4 et ren10, qui ont la capacité d'affecter le développement des poils des racines seulement dans le cadre du mutant rhd3.Nous avons également étudié l'interaction entre rhd3 et deux autres gènes connus, shv2 et bot1, pour leur implication dans la formation des poils absorbants. Le gène shv2 code pour une protéine ancrée à un GPI (Glycosylphosphatidylinositol), semblable à la protéine COBRA. Le mutant shv2 ralentit l'allongement des poils. L'analyse du double mutant shv2/rhd3 a révélé que la mutation shv2 accentue le phénotype de rhd3. Le gène bot1 code pour une protéine semblable à la katanine qui sert à sectionner les microtubules. Le mutant bot1 est connu pour induire la formation ectopique de poils absorbants. Le double mutant bot1/rhd3 présente quant à lui un phénotype atténué de rhd3.
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Chan, Man-lok Mandy, and 陳文樂. "A study of RhoV and PAK4 signaling in hepatocarcinogenesis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47053434.
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Lüttringhaus, Timo. "RHD-Genotypisierung bei D-negativen Ostasiaten." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:289-vts-61148.
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Yi, Keke. "Temporal regulation of root hair development by RHD6 family genes." Thesis, University of East Anglia, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502367.
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The key transcriptional regulators that regulate root hair initiation and tip growth are unknown. While many genes have been reported that participate in root hair development, especially root hair tip growth, none that regulate root hair initiation and tip growth has been identified to date. The aim of this thesis is to characterise the role of a family of transcription factors that control these processes and to construct a regulatory network for root hair growth and initiation. Previously, we isolated two bHLH transcription factors, RHD6 and RSL1, that positively regulate root hair initiation. These two genes belong to the bHLH VIllc subfamily, which includes four other paralogues (RSL2 to RSL5) that form a sister clade to RHD6 and RSL1. To characterize the function of the sister clade genes, I examined the phenotypes of all the available knockout mutants and determined their expression patterns. The genetic data shows that the sister clade genes function downstream of RHD6 and RSLl in root hair development, with RSL4 regulating both root hair initiation and tip growth and RSL2, RSL3 and RSL5 controlling root hair tip growth. Root hair tip growth is totally abolished in plants having mutations in both RSL2 and RSL4. Consistent with the genetic data, expression of RHD6 family genes follows a temporal pattern that reflects the timing of their roles during development. RHD6 and RSLl are expressed in root hair cells around the root meristem and elongation zones to regulate the early event of root hair initiation. RSL4 is expressed in root hair cells around root hair initiation zone to direct late event of root hair initiation; then, together with RSL2 and RSL3, which are also expressed in root hair cells around root hair initiation zone, RSL4 maintains root hair tip growth; RSL5, which is regulated by the other members, is also expressed in root hair cells. As auxin and ethylene also regulate root hair initiation and tip growth, and can partially restore the root hair development in rhd6/rsll mutant, I also investigated how auxin and ethylene interact with the RHD6 family genes to regulate root hair development. I showed that auxin and ethylene can bypass RHD6 and RSLl to regulate the down stream sister clade genes during root hair development. Furthermore, RHD6 and auxin/ethylene regulate root hair tip growth through RSL2 and RSL4. And low phosphate stress also regulates root hair by modulating RSL2 and RSL4 transcription. In summary, we found a subgroup of key regulator genes in the same bHLH subfamily form a regulatory network and temporally control root hair initiation and tip growth, and the internal and external (phosphate availability) factors regulate root hair development through these genes.
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Amaral, Daphne Renata Tavares. "Determinação do genótipo RHD fetal através do plasma materno em gestantes RhD-negativo de uma população do Brasil." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310413.
Full textAbstract:
Orientador: Lilian Maria de CastilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: A análise de plasma materno para a determinação do genótipo RHD fetal é uma importante ferramenta no acompanhamento de gestantes RhD-negativo, especialmente em pacientes aloimunizadas. Este trabalho verificou a acurácia da genotipagem RHD fetal pela análise do plasma materno em uma população do Brasil. Foram analisadas 88 gestantes RhD-negativo entre 11 e 39 semanas de gestação, com idade mediana de 28 anos. Treze (14,78%) pacientes encontravam-se aloimunizadas com anti-D. Foram utilizados primers e sondas para detecção do gene RHD (exons 4, 5 e 10) por PCR em tempo real. Como controle interno, utilizou-se um conjunto de primers e sondas para identificar o genes SRY e CCR5. Sangue periférico ou sangue de cordão umbilical dos respectivos neonatos foram coletados durante o parto para a realização da fenotipagem RhD. A genotipagem RHD convencional foi realizada em todas as 88 amostras de DNA materno. Oitenta e três (94,32%) gestantes apresentaram a deleção do gene RHD e em 5 (5,68%) amostras foram identificadas variantes do gene RHD (3 RHD e 2 DFR). A genotipagem RHD convencional foi também realizada em 17 amostras de DNA paternas. Quinze amostras (88,24%) foram genotipadas como RHD+ (5 RHD+/RHD+ e 10 RHD+/RHD-) e 2 (11,76%), como RHD-. Cinqüenta e oito (65,91%) fetos foram genotipados como RHD+. Vinte e sete (30,68%) amostras apresentaram ausência completa do gene RHD e três fetos apresentaram amplificação apenas para o exon 10, demonstrando a presença de uma possível variante RHD ou RHD-CE-Ds. Todos os resultados da genotipagem RHD fetal foram concordantes com a fenotipagem neonatal incluindo os 3 fetos com a variante RHD, fenotipados como RhD-. Nossos resultados indicam que a genotipagem RHD fetal através da análise do plasma materno amplificando 3 regiões do gene RHD (exons 4, 5 e 10) é adequada para a aplicação clínica. Este protocolo pode-se tornar prática em um futuro próximo
Abstract: Maternal plasma analysis for determination of the fetal RHD status is an important tool for the management of RhD-negative pregnant, specially alloimunized women. We assessed the accuracy of fetal RHD genotyping by analysis of maternal plasma in a multi-ethnic population. We analyzed plasma samples from 88 RhD-negative pregnant women between 11 and 39 weeks of gestation, median age of 28 years old to determine the fetal RHD genotype. This population was from Southeastern Brazil with high mixed ethnic background. Thirteen patients (14,78%) had anti-D alloantibody. We used TaqMan primers and probes to detect exons 4, 5 and 10 of RHD, by real-time PCR. As internal controls, we used primers/probes sets to SRY and CCR5. Peripheral or umbilical cord bloods from respective neonates were collected during delivery and hemagglutination was performed. Conventional RHD genotyping was realized in all pregnant. Eighty-three patients had a deletion of RHD gene and five samples were identified RHD variants (3 RHD and 2 DFR). The conventional RHD genotyping was also performed on 17 DNA samples from fathers. Fifteen samples were genotyped as RHD+ (5 RHD+/RHD+ and 10 RHD+/RHD-) and 2 RHD-negative. Fifty-eight (65,91%) fetuses were genotyped as RHD+. Twenty-seven (30,68%) samples showed completely absence of RHD and three fetuses showed amplification only for the exon 10, demonstrating the presence of a possible variant (RHD or RHD-CE-Ds). All fetal RHD results agreed with the neonatal typing including the 3 fetuses with RHD variant, phenotyped as RhD-negative. Thus, the accuracy of the fetal RHD genotyping in this population was 100%. The earliest pregnancy in which fetal RHD was detected was 11 weeks. Our findings indicate that the accuracy of fetal RHD genotyping from maternal plasma using 3 regions (exons 4, 5 and 10) can be sufficient for clinical application in a multi-ethnic population. This knowledge helped us on the development of a feasible protocol for fetal RHD genotyping on DNA from maternal plasma in our population and should become practice in the near future
Mestrado
Ciencias Basicas
Mestre em Clinica Medica
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Nagl, Lisa P. "Improving the detection of donations within the RHD negative blood donor panel which weakly express the RHD antigen." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/73333/1/Lisa_Nagl_Thesis.pdf.
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This project improved the detection and classification of very weakly expressed RhD variants in the Australian blood donor panel and contributed to the knowledge of anti-D reactivity patterns of RHD alleles that are undescribed. As such, the management of donations possessing these RHD alleles can be improved upon and the overall safety of transfusion medicine pertaining to the Rh blood group system will be increased. Future projects at ARCBS will be able to utilise the procedures developed in this project, thereby decreasing throughput time. The specificity of current testing will be improved and the need for outsourced RHD testing diminished.
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Rosdahl, Karl Joakim. "Cosmological RHD simulations of early galaxy formation." Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10075/document.
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Avec l’essor actuel de la sophistication et de l’efficacité des codes de cosmologie hydrodynamique,il est devenu possible d’inclure le transfert radiatif (RT) des photons ionisants dansles simulations cosmologiques, soit en post-traitement, soit en simulations couplées rayonnement+hydrodynamique (RHD). Malgré de nombreux obstacles, il y a eu cette derniéredécennie beaucoup de recherches menées sur les différentes stratégies et implémentations,dû au fait qu’un nombre de problèmes intéressants peuvent être désormais abordés par laRT et RHD, par exemple comment et quand l’Univers s’est réionisé, comment l’émissionradiative des étoiles et des noyaux actifs de galaxies se comportent pour réguler la formationdes structures à des échelles petites et grandes, et quelles prédictions et interprétationsnous pouvons faire des phénomènes observés, tels que la forêt Lyman-alpha et des sourcesdiffuses de rayonnement.Cela coïncide avec l’avènement du télescope spatial James Webb (JWST) et d’autresinstruments de pointe qui sont sur le point de nous donner un aperçu sans précédent sur lafin des âges sombres de l’Univers, quand le cosmos est passé d’un état froid et neutre à unétat chaud et ionisé, à la suite de l’apparition des sources radiatives.Notre préoccupation principale étant les rétroactions radiatives des premieres structures,nous avons mis en place une version RHD du code cosmologique Ramses, que nous appelonsRamsesRT, basée sur la méthode des moments. Ce code nous permet d’étudier les effets durayonnement ionisant dans les simulations cosmologiques RHD qui tirent pleinement profitdes stratégies de raffinement adaptif de grille et de parallélisation de Ramses. Pour rendreauto-cohérent le RHD nous avons également mis en oeuvre une thermochimie hors-équilibreincluant des espèces de l’Hydrogène et de l’Hélium qui interagissent avec le rayonnementtransporté.Je présente dans cette thèse une description détaillée de RamsesRT et de nombreux testscontribuant à sa validation.Jusqu’à présent nous avons utilisé RamsesRT pour étudier l’émission Lyman-alpha decourants d’accrétion, qui sont prédits à grand redshift par les simulations cosmologiques,mais n’ont jamais été clairement identifiés par les observations. Nous avons également étudiéle chauffage gravitationnel dans ces courants pour déterminer si ce dernier pouvait être lasource motrice principale des Lyman-alpha blobs, un phénomène observé qui a été beaucoupétudié et débattu au cours de la dernière décennie. Cet étudie nous permet de conclure queles Lyman-alpha blobs peuvent, en principe, être alimentés par le chauffage gravitationnel,et que d’autre part, les courants d’accrétion sont sur le point d’être directement détectablesavec des instruments à venir.Mes intentions futures sont d’utiliser RamsesRT dans les simulations cosmologiques àhaute résolution, de la formation des premiéres galaxies jusqu’à l’époque de la réionisation,et ainsi étudier comment la rétroaction radiative affecte la formation et l’évolution de cesgalaxies et de faire des prévisions d’observation qui peuvent être testées avec des instrumentssophistiqués tels que le JWSTWith the increasing sophistication and efficiency of cosmological hydrodynamics codes, ithas become viable to include ionizing radiative transfer (RT) in cosmological simulations,either in post-processing or in full-blown radiation-hydrodynamics (RHD) simulations. Inspite of the many hurdles involved, there has been much activity during the last decade or soon different strategies and implementations, because a number of interesting problems canbe addressed with RT and RHD, e.g. how and when the Universe became reionized, howradiation from stars and active galactic nuclei plays a part in regulating structure formationon small and large scales, and what predictions and interpretations we can make of observedphenomena such as the Lyman-alpha forest and diffuse sources of radiation.This coincides with the advent of the James Webb space telescope (JWST) and otherstate-of-the-art instruments which are about to give us an unprecedented glimpse into theend of the dark ages of the Universe, when the cosmos switched from a cold and neutralstate to a hot and ionized one, due to the turn-on of ionizing radiative sources.With a primary interest in the problem of radiative feedback in early structure formation,we have implemented an RHD version of the Ramses cosmological code we call RamsesRT,which is moment based and employs the local M1 Eddington tensor closure. This code allowsus to study the effects of ionizing radiation on-the-fly in cosmological RHD simulationsthat take full advantage of the adaptive mesh refinement and parallelization strategies ofRamses. For self-consistent RHD we have also implemented a non-equilibrium chemistry ofthe atomic hydrogen and helium species that interact with the transported radiation.I present in this thesis an extensive description of the RamsesRT implementation andnumerous tests to validate it.Thus far we have used the RHD implementation to study extended line emission fromaccretion streams, which are routinely predicted to exist at early redshift by cosmologicalsimulations but have never been unambiguously verified by observations, and to investigatewhether gravitational heating in those streams could be the dominant power source ofso-called Lyman-alpha blobs, an observed phenomenon which has been much studied anddebated during the last decade or two. Our conclusions from this investigation are thatLyman-alpha blobs can in principle be powered by gravitational heating, and furthermorethat accretion streams are on the verge of being directly detectable for the first time withupcoming instruments.My future intent is to use RamsesRT for high-resolution cosmological zoom simulations ofearly galaxy formation, up to the epoch of reionization, to study how radiative feedbackaffects the formation and evolution of those galaxies and to make observational predictionsthat can be tested with upcoming instruments such as the JWST
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Perera, W. Shermal. "Binding and molecular characterisation of monoclonal RhD antibodies." Thesis, University of Aberdeen, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342706.
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Monoclonal RhD antibodies (anti-RhD) may potentially be used in preventing Rh alloimmunisation of women delivering RhD-positive babies, and thereby preventing haemolytic disease of the newborn (HDN). Binding and molecular analyses were performed on a range of monoclonal anti-RhDs to understand the interaction between the antibody and antigen. A flow cytometry (FCM) assay system was developed to analyse the binding of the anti-RhD to human group O R1R2 red blood cells (RBC). A panel of 30 anti-RhD preparations were studied using this assay and Vmax (maximum binding) and KD (equilibrium constant) were determined for each antibody. The antibodies were categorised into 3 groups (low, medium and high binders) according to their Vmax. Furthermore, the Vmax was converted to the number of antibody molecules bound per RBC (NMBR) by using a correlation curve generated from running parallel FCM and radioiodination assays (RIA). Scatchard analysis of the RIA data indicated that the total NMBR for O R1R2 RBC was 27,300 antigen sites/cell. Molecular analysis involved cloning and sequencing of 11 anti-RhD. Heavy chains (HC) preferentially used gene segments from the VH3 and VH4 families, and kappa chain (κ LC) usage was restricted to DPK9. Four sets of antibodies, showed restricted D gene segments (encode part of the HCDR3) which indicated possible importance for epitope specificity. Analysis of V gene sequence indicated that common VH and VL pairings were found used by the medium binders. The high and low binders had unique VH and VL pairings, although the high binders also showed greater somatic mutations from their respective germline genes. It was concluded that the fit of the antibody to the RhD antigen is dependent on both the VH and VL usage and pairing, and that the precise epitope specificity of these antibodies may require HCDR3 interaction.
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Credidio, Débora Castilho. "Variantes do antígeno RhD = estudo sorológico e molecular." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310414.
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Orientador: Lilian Maria de CastilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: Discrepâncias na tipagem Rh ocorrem devido à presença de variantes do antígeno RhD, em especial D fraco e D parcial. Diferentes reagentes anti-D monoclonais tem sido desenvolvidos para identificar estas variantes, mas a caracterização molecular pode garantir um resultado mais específico com melhor definição do tipo de variante presente. O fenótipo D fraco ocorre por alterações de nucleotídeos que levam a substituição de aminoácidos na região transmembranar e intracelular da proteína Rh enquanto que o fenótipo D parcial ocorre por alterações de nucleotídeos ou rearranjos gênicos que levam a substituição de aminoácidos na região extracelular da proteína Rh, resultando em fenótipos sorológicos distintos e aloimunização anti-D. Nossos objetivos foram avaliar reagentes anti-D e métodos sorológicos e moleculares na detecção e identificação destas variantes. Foram estudadas 335 amostras de sangue e DNA de doadores e pacientes fenotipados previamente como RhD fraco, ou que apresentaram resultados discrepantes na tipagem RhD. Das 335 amostras estudadas, 215 (64,1%) foram identificadas como D fraco, 89 (26,5%) como D parcial, 3 (1%) como DEL, 11 como RhD-positivo e 17 como RhD-negativo. Entre as amostras D fraco, 76 eram DF1 (35,3%); 75 DF2 (34,9%); 13 DF3 (6,1%); 49 DF4 (22,8%) e 2 DF5 (0,9%). Entre as amostras D parcial, 9 (10,1%) eram DAR, 25 (28,1%) DFR, 6 (6,7%) DBT, 1 (1,1%) DHMi, 1(1,1%) RoHAR, 26 (29,2%) DVI, 14 (15,8%) DVa, 5 DIVb (6,6%) e 2 (2,3%) DVII . Nas amostras DEL, duas foram identificadas molecularmente como RHD(IVS5-38DEL4) e uma como RHD(K409K). Nossos resultados demonstram que a utilização de diferentes reagentes anti-D e métodos na rotina sorológica pode indicar a presença de uma variante do antígeno RhD que deve ser investigada por análise molecular. Esta estratégia pode auxiliar na diferenciação entre D fraco e D parcial e caracterizar as variantes que levam a aloimunização anti-D. Esta distinção é importante na seleção de sangue para pacientes e na prevenção da doença hemolítica do feto e recém-nascido
Abstract: Rh discrepancies are becoming a problem during routine testing due to partial D or weak D phenotypes. Panels of monoclonal antibodies (MoAb) are being developed in order to identify D variants such as partial D and weak D when there are anomalous RhD typing results but molecular characterization offers a more specific grouping of weak and partial D. The weak D phenotype is caused by many different RHD alleles encoding aberrant RhD proteins, resulting in distinct serologic phenotypes and anti-D immunizations. We evaluated currently used serologic methods and reagents to detect and identify D variants and correlated the results with molecular analyses. A total of 335 blood samples from Brazilian blood donors and patients with discrepant results of D typing in routine were analyzed. In total, 215 (64.1%) weak D, 89 (26.5%) partial D, 3 (1%) DEL, 11 RhD-positive and 17 RhD-negative were identified. Among weak D samples, 76 weak D Type 1 (35.3%); 75 weak D Type 2 (34.9%); 13 weak D Type 3 (6.1%); 49 weak D Type 4 (22.8%) and 2 weak D Type 5 (0.9%) alleles were found. Among the partial D samples, 9 (10.1%) DAR, 25 (28.1%) DFR, 6 (6.7%) DBT, 1 (1.1%) DHMi, 1(1.1%) RoHAR, 26 (29.2%) DVI, 14 (15.8%) DVa, 5 DIVb (6.6%) and 2 (2.3%) DVII were observed. Two samples identified as DEL by adsorption/elution were characterized by molecular analyses as RHD(IVS5-38DEL4) and one sample as RHD(K409K). Our results showed that the use of different methods and anti-D reagents in the serologic routine reveal some D variants that can be further investigated. Molecular methods can help to differentiate between partial D and weak D and characterize the weak D types providing additional information of value in the RhD typing. This distinction is important for selection of blood products and to prevent anti-D hemolytic disease of the fetus and newborn
Mestrado
Ciencias Basicas
Mestre em Clinica Medica
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Mota, Mariza Aparecida 1956. "Identificação do gene RHD em doadores voluntários de sangue fenotipados como RHD negativo utilizando pools de DNA = RHD allelic identification among D-brazilian blood donors as a routine test using pools of DNA." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310410.
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Orientador: Lilian Maria de CastilhoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: Alelos RHD que levam à redução da expressão do antígeno D na superfície dos eritrócitos podem levar à tipagem errônea como D- por técnica sorológica e podem causar imunização anti-D quando transfundidos em pacientes. A fim de determinar a ocorrência de tais alelos em doadores de sangue aparentemente D-, foi implementada técnica molecular de rotina utilizando um pool de DNAs de doadores de sangue. Um total de 2450 amostras previamente tipadas como D- foram testadas em pools de 10 amostras para o polimorfismo RHD específico, intron 4 e éxon 7. Nos pools que apresentaram resultado de PCR positivo, as amostras foram reavaliadas individualmente utilizando PCR exon-específico, métodos sorológicos e sequenciamento genético. Dentre as 2.450 amostras de doadores D- testadas, 101 (4,1%) carreavam o gene RHD. Foi identificada a presença de RHD não funcional (RHD'psi', RHD*CE(2-9)-D e RHD*CE(3-7)-D), diferentes alelos de D fraco tais como RHD*weak D type 1, RHD*weak D type 4.3, RHD*weak D type 5, RHD*weak D type 38 e RHD*DEL. Uma metodologia utilizando a técnica de PCR foi empregada como teste de rotina para o gene RHD utilizando pools de 10 amostras de DNA de doadores de sangue. Foi possível a integração da genotipagem RHD em programas de triagem de rotina utilizando pools de DNA. Como resultado, 19 (0,8%) dos doadores de sangue que carreavam fenótipos D fraco ou Del, com potencial de causar imunização anti-D em receptores, foram reclassificados como D+. Entretanto, seria necessário adaptar a estratégia de genotipagem RHD ao espectro de alelos prevalente em cada população
Abstract: RHD alleles leading to a reduced expression of D antigen of the red blood cell (RBC) surface may be erroneously typed as D negative by serology and may cause anti-D immunizations when transfused to recipients. We have therefore investigated the occurrence of such alleles among apparent D negative blood donors, molecular typing was implemented as a routine test using a pool of DNA. A total of 2,450 pretyped D negative samples was tested in pools of 10 for the RHD-specific polymorphism in intron 4 and exon 7. Samples in PCR positive pools were individually reevaluated by exon-specific PCRs, sequencing and serologic methods. Our results showed that among 2,450 serologically D negative blood donor samples tested, 101 (4.1%) carried the RHD gene. Nonfunctional RHD (RHD*'psi', RHD*CE(2-9)-D and RHD*CE(3- 7)-D), different weak D alleles such as RHD*weak D type 1, RHD*weak D type 4.3, RHD*weak D type 5, RHD*weak D type 38 and RHD*DEL were identified. We employed a PCR-based assay for RHD as a routine test using pools of 10 DNA blood donor samples. The integration of RHD genotyping into the routine screening program using pools of DNA samples was straightforward. As a consequence, 19 (0.8%) blood donors carrying a weak D and Del phenotypes with the potential of causing anti-D immunizations in recipients were reclassified as RhD positive. For each population, it would be necessary to adapt the RHD genotyping strategy to the spectrum of prevalent alleles
Doutorado
Clinica Medica
Doutora em Ciências
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Schmidt, Luciana Cayres. "Genotipagem RHD fetal no plasma materno como ferramenta não invasiva na predição do risco da doença Hemolítica Perinatal em gestantes RHD negativo." Universidade Federal de Minas Gerais, 2011. http://hdl.handle.net/1843/BUOS-8L7MQ6.
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The management of RhD negative pregnant women is based on the premise that their fetuses may be at risk of developing hemolytic disease (DHPN), which could bring serious risks to the fetus. Invasive procedures such as amniocentesis or cordocentesis can be used to define the fetal RhD phenotype, however, it offers risks to both fetus and pregnant woman. The ability to detect fetal RHD gene in DNA from maternal plasma allowed a major advance in the care protocol to RhD negative pregnant women for being a non-invasive procedure and therefore carries no risk to the mother or fetus. Methods: 55 blood samples from RhD negative pregnants were processed for extraction of fetal DNA. Real time PCR was performed to amplify segments of exons 5 and 7 of RHD gene. The results of fetal genotyping using maternal plasma were compared with the RhD phenotype of newborns, performed in cord blood sample obtained at birth. PCR for detection of SRY gene and for the study of RHD zygosity was also performed, when the paternal sample was available. Results: The results of fetal RHD genotyping could be compared with 43 RhD phenotypes of newborn. There were five inconclusive results, no false negative and one false positive due to a probable incorrect RhD phenotyping. The test sensitivity was 100%, specificity was 94,1% and concordance between molecular and serological tests was 97,7% if we consider that the only discordant serological results was correct. However, in this case, genotyping from maternal plasma was concordant to that determined from the newborn buccal cells. Conclusion: The test for noninvasive fetal RHD genotyping was a sensitive and viable tool in management of RhD negative pregnants.O acompanhamento a gestantes RhD negativo é baseado na premissa de que seus fetos podem estar em risco de desenvolver a doença hemolítica perinatal (DHPN), o que pode trazer sérios riscos ao feto. Procedimentos invasivos como amniocentese ou cordocentese podem ser utilizados para se conhecer o fenótipo RhD fetal, entretanto, oferecem riscos ao feto e à gestante. A possibilidade de se detectar o gene RHD no DNA fetal extraído do plasma materno possibilitou um grande avanço no protocolo de atendimento a gestantes RhD negativo por ser um procedimento não invasivo e que, portanto, não acarreta qualquer risco à mãe ou ao feto. Material e métodos: 55 amostras de sangue de gestantes RhD negativo foram processadas para purificação do DNA fetal. PCR em tempo real foi realizada para amplificar segmentos dos exons 5 e 7 do gene RHD. Os resultados da genotipagem fetal no plasma materno foram comparados com a fenotipagem RhD dos recém-nascidos, realizada em amostras de sangue umbilical colhida ao nascimento. Também foram realizadas PCR para detecção do gene SRY e para estudo da zigozidade RHD paterna, quando a amostra paterna estava disponível. Resultados: Os resultados da genotipagem RHD fetal puderam ser comparados com 43 fenótipos RhD dos recém-nascidos. Houve cinco resultados inconclusivos, nenhum falso negativo e um falso positivo, devido a uma provável fenotipagem RhD incorreta. A sensibilidade do teste foi de 100%, a especificidade foi de 94,1% e a concordância dos resultados moleculares com os sorológicos foi de 97,7%, se considerarmos que o único resultado sorológico discordante estava correto. Entretanto, este não parece ser o caso, uma vez que a genotipagem usando DNA fetal extraído de plasma materno foi concordante com a genotipagem RHD a partir de células da mucosa bucal do recém-nascido. Conclusão: O teste para a genotipagem RHD fetal não invasiva mostrou-se sensível e viável como ferramenta auxiliar na rotina de atendimento a gestantes RhD negativo.
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Schweidler, Kerstin. "Pränatale RhD- und AB0-Diagnostik aus Fruchtwasser mittels Polymerasekettenreaktionen." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=965811506.
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Machado, Isabela Nelly. "Genotipagem RHD fetal atraves da analise do plasma materno." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313178.
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Orientadores: Ricardo Barini, Lilian Maria de CastilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: A Doença Hemolítica Perinatal ainda contribui para as taxas de morbi-mortalidade perinatal, a despeito do amplo uso da imunoprofilaxia. A determinação da tipagem sanguínea RhD fetal é útil para o acompanhamento pré-natal das gestantes RhD-negativo sensibilizadas e para a profilaxia da Doença Hemolítica Perinatal, evitando-se desnecessários procedimentos invasivos, investigações sorológicas e administração da imunoglobulina humana nos casos de fetos RhD-negativo. A análise molecular do plasma matemo abriu novas possibilidades para o diagnóstico pré-natal não invasivo, onde a genotipagem RHD fetal é uma das aplicações clínicas mais relevantes até o momento. Objetivo: Avaliar o desempenho da genotipagem RHD fetal através da análise do plasma matemo como método diagnóstico pré-natal não invasivo. Método: Foi conduzido um estudo de validação de teste diagnóstico a partir de 81 amostras sangüneas obtidas de gestantes RhD-negativo, entre 4 e 41 semanas de gestação. O DNA fetal foi extraído dos respectivos plasmas matemos utilizando kits comercialmente disponíveis. As regiões exon 10 e intron 4 do gene RHD foram testadas através da reação em cadeia da polimerase alelo- específica (AS-PCR) convencional. Os resultados da genotipagem fetal foram comparados com a tipagem sanguínea neonatal e os dados analisados pelo softwware SAS - versão 8.2@ (1999-2001). Resultados: 15 amostras foram obtidas no primeiro trimestre, 37 no segundo trimestre e 29 no terceiro trimestre. Houve falha de amplificação em 6 amostras, 3 RhD-negativo e 3 RhD-positivo à tipagem neonatal. A concordância entre os resultados da genotipagem e da tipagem neonatal foi de 97,3%, sensibilidade de 98,3% e especificidade de 93,8%. Foi observado 1 falso positivo no terceiro trimestre e 1 falso negativo no primeiro trimestre. Conclusão: AS-PCR convencional é um método com bom desempenho para a genotipagem RHD fetal através da análise do plasma matemo, como método diagnóstico pré-natal não invasivo
Abstract: Hemolytic Disease of the Fetus and Newborn still contributes to perinatal morbidity and mortality, in spite of the widespread munoprophylaxis. Prenatal identification of fetal RHD status is a goal of obstetrical practice, in order to prevent maternal immunization and to help in the management of alloimmunized pregnant women. The analysis of the maternal plasma opened up new posibilities for noninvasive prenatal diagnosis and the determination of fetal RHD genotype is one of the most relevant application of this molecular analysis. Objective: To establish the performance of conventional PCR analysis of the maternal plasma as a method to genotype fetal RHD. Method: A validity of diagnostic test was conduced with 81 peripheral blood samples obtained from RhD-negative pregnant women, between 4 and 41 weeks of gestation. Commercially available kits were used to extract DNA from the maternal plasma. Exon 10 and intron 4 RHD gene regions were tested using conventional Allele-Specific Polymerase Chain Reaction (AS-PCR). Fetal RHD genotyping by PCR on maternal plasma was compared to conventional Rh typing in neonatal period and data analysed by SAS- 8.2 version@ (1999-2001). Results: Samples were obtained as follows: 15 on 1 si, 37 on 2nd and 29 on 3rd trimester. Amplification failed in six of the specimens, 3 were RhD-negative and 3 RhD-positive at neonatal typing. Concordance between the genotyping and neonatal typing was 97.3%, sensitivity of 98.3% and specificity of 93.8%. One false positive in the third trimester and one false negative in the first trimester were observed. Conclusion: Conventional AS-PCR is an accurate method for fetal RHD genotyping on maternal plasma, as a noninvasive prenatal dignosis
Mestrado
Tocoginecologia
Mestre em Tocoginecologia
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Santos, Fábio Alexandre Abade dos. "Quadro anatomo-histopatológico e diagnóstico molecular da doença hemorrágica viral em coelho-bravo." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2018. http://hdl.handle.net/10400.5/15206.
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Dissertação de Mestrado Integrado em Medicina VeterináriaO vírus da doença hemorrágica dos coelhos de tipo 2 (RHDV2) foi detetado em Portugal pela primeira vez, em 2012, e encontra-se atualmente disseminado em todo o território nacional incluindo Madeira, Açores e Berlengas. O papel ecológico e económico do coelho-bravo, aliado à sua importância para os níveis tróficos superiores, levou a que o Governo Português ativasse em 2017 um plano para controlo desta doença (Despacho 4757/2017 de 31 de Maio). Este trabalho teve como objetivo estabelecer padrões de lesão histopatológica nos principais órgãos afetados (fígado, pulmão, baço, duodeno, coração, entre outros) durante a infeção por RHDV2 e relacioná-los com os padrões de distribuição de cargas virais (medidos através dos valores de Cq obtidos por RT-qPCR) em sete matrizes (fígado, baço, duodeno, fezes, rim, pulmão e ventrículo esquerdo). Todos os coelhos-bravos investigados (n=49), foram obtidos no âmbito deste estudo, durante suspeitas de surtos de DHV, sendo oriundos de vários locais. No grupo dos animais não vacinados, o diagnóstico virológico e histopatológico raramente suscitou dúvidas e não foram encontradas lesões macro e microscópicas diferentes entre os coelhos jovens e os animais adultos. No entanto foi observada uma diminuição significativa das cargas virais nos órgãos dos animais vacinados para RHDV2 quando comparados com os animais não vacinados, tal como já descrito na literatura. Em alguns animais vacinados, foi difícil detetar o vírus por métodos moleculares apesar da presença de graves lesões histopatológicas compatíveis com DHV. No caso dos animais vacinados, a valores de Cq tendencialmente maiores, correspondeu uma menor prevalência do padrão lesional hepático mais grave. Contrariamente, nos animais não vacinados, foram encontrados valores de Cq tendencialmente mais baixos no fígado (maiores cargas virais), correspondendo a um padrão lesional mais grave. Os dados obtidos indicam também que o fígado não é o órgão de eleição para diagnóstico de RHDV2 em animais vacinados, já que o pulmão foi a matriz onde o vírus foi mais detetado. Curiosamente, o ventrículo esquerdo apresentou-se como a matriz com maior percentagem de positividade em todos os grupos pelo que a pertinência da sua utilização sistemática no diagnóstico molecular, deve ser investigada. Foi ainda realizada a pesquisa de RHDV2 em outras espécies simpátricas: lebre ibérica (n=2), toirão (n=1), texugo (n=1), sacarrabos (n=1), roedores (n=18), pardalcomum (n=1), insetos (n> 2568) e ixodídeos (n=28)). Foi detetado RNA viral no pulmão de um toirão, no fígado e ventrículo esquerdo de uma lebre, nas fezes do pardal comum, e em 3 famílias de insetos (Ceratopogonidae, Staphylinidae e Simuliidae). Este trabalho trouxe novos dados para a compreensão da interface patogenia-diagnóstico e para a compreensão da eco-epidemiologia da DHV
ABSTRACT - Anatomo-histopathological analysis and molecular diagnosis of Viral Haemorrhagic Disease in wild rabbit - Rabbit haemorrhagic disease virus 2 (RHDV2) was detected in Portugal for the first time in 2012. It is currently widespread in the continent and islands (Azores, Madeira and Berlengas). The ecological and economic role of the wild rabbit and its crucial importance for the higher trophic levels, led the Portuguese Government to activate, in 2017, an action plan to control this disease (Dispatch 4757/2017 of 31 May). This work aimed to establish patterns of histopathological lesions in the organs affected during infection (liver, lung, spleen, thymus, duodenum, heart among others) and to relate them to the viral load distribution patterns, measured by the Cq values obtained with a RHDV2-specific RT-qPCR, in seven biological matrices (liver, spleen, duodenum, faeces, kidney, lung and left ventricle). All the wild rabbits investigated (n = 49) were obtained within the scope of this study and originated from several locations (mainly two wild-rabbit farms with management conditions and different purposes) during suspected outbreaks of haemorrhagic viral disease. In the group of unvaccinated animals, the virological and histopathological diagnosis rarely raised doubts and no different macro and microscopic lesions were found between young rabbits and adult animals No differences in the macro and microscopic lesions were found between young and adult rabbits but a significant decrease in the viral loads of organs was observed in RHDV2 vaccinated rabbits, when compared to non-vaccinated rabbits, as described before in the literature. In some animals that had been vaccinated, it was difficult to detect the virus by molecular methods, although severe histopathological lesions were identified. For the vaccinated group, the increase in the Cq values tended to be accompanied by a more variable lesional pattern, with the more severe ones being less prevalent. In the liver of nonvaccinated rabbits, for example, as Cq values decreased (corresponding to higher viral charges), more severe lesional patterns were observed. Our data indicate that the liver is not the organ of choice for RHDV2 molecular diagnosis in vaccinated animals, since the virus was more often detected in the lungs. Interestingly, the left ventricle showed the highest percentage of positivity in all groups, so the relevance of its systematic use for diagnosis should be considered and investigated. RHDV2 was also investigated in other sympatric species, such as Iberian hare (n=2), toad (n=1), badger (n=1), rodents (n=18), common sparrow (n=1), insects (n>2568) and ixodids (n=38). Viral RNA was detected in the lung of a toad, in the liver and heart of a hare in the faeces of the common sparrow, and in 3 families of insects (Ceratopogonidae, Staphylinidae and Simuliidae). This work brought new insights to the pathogeny-diagnosis interface and to the comprehension of the disease eco-epidemiology.
Financiado por: Fundo Florestal Permanente
N/A
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Coutinho, Conrado Milani. "Diagnóstico do fator RhD utilizando a reação em cadeia da polimerase convencional." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/17/17145/tde-14012009-183745/.
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A aplicação dos métodos de biologia molecular tem acrescentado benefícios aos métodos convencionais de diagnóstico do grupo sangüíneo Rhesus (Rh). Alguns estudos evidenciaram a superioridade prática da genotipagem RhD por reação em cadeia da polimerase (PCR) em relação às técnicas de identificação do fenótipo dos antígenos do grupo Rh obtidas pela hemaglutinação. Esta análise molecular tem sido realizada utilizando-se várias seqüências cromossômicas e diferentes tipos de técnicas. O grupo Rh contém dois genes homólogos, um codificando o antígeno D e o outro os antígenos C/c e E/e. Os objetivos deste projeto foram: (1) Detectar a presença de seqüência RhD específica dos indivíduos Rh positivo; (2) Comparar a presença/ausência destas seqüências com o grupo sanguíneo detectado pela hemaglutinação e calcular a sensibilidade e a especificidade da PCR. Para cumprir estes objetivos, foram analisadas amostras de DNA extraídas de sangue periférico de 23 indivíduos (4 homens e 19 mulheres) Rh positivo (11) e negativo (12) para amplificação de seqüências dos genes RhD e RhCE utilizando a técnica de PCR convencional. Nestas amostras, a comparação dos resultados da PCR com os da hemaglutinação demonstrou total concordância entre os testes. A sensibilidade do método foi avaliada pela realização da PCR em amostras de sangue Rh positivo diluídas em água e em sangue Rh negativo, amplificando o DNA na concentração de até 4 pg/l. Estes resultados indicaram que a técnica de PCR mostrou-se efetiva no diagnóstico da genotipagem do fator Rh, vislumbrando-se a possibilidade de sua utilização em outros tecidos de origem êmbrio-fetal para orientação de diagnóstico fetal invasivo e do uso profilático da imunoglobulina anti-D apenas nos casos de incompatibilidade Rh materno-fetal. Adicionalmente, indicaram que havendo melhora da sensibilidade desta técnica será possível detectar quantidades objetivamente menores de DNA fetal na circulação materna, fundamentando um importante passo rumo ao diagnóstico do fator Rh fetal por técnica não invasiva.Molecular biology techniques have added some advantages to conventional diagnosis of the Rhesus (Rh) blood group. Many researches have demonstrated the practical superiority of RhD genotyping using polymerase chain reaction (PCR) over phenotypic identification tests obtained by hemagglutination. The use of different kinds of molecular analysis techniques and genetic sequences has been described. The Rh blood group contains two homologous genes, one encoding the D antigen and the other one coding C/c and E/e antigens. This study objectives were: (1) Detect the RhD sequence specific for the Rh positive individuals; (2) Compare the presence/absence of these sequences with the blood group identified by hemagglutination to calculate PCRs sensitivity and specificity rates. To accomplish these objectives, DNA extracted from venous blood of 23 individuals (4 men and 19 women), Rh positive (11) and negative (12), were analyzed using conventional PCR to amplify RhD and RhCE gene sequences. The comparison of PCR with hemagglutination results has shown total agreement. The sensitivity of this PCR method was evaluated using progressive dilutions of Rh positive samples on water and also on Rh negative samples, which demonstrated successful amplification of until 4 pg/l DNA concentration. These results have indicated that PCR was effective for the RhD genotyping, foreseeing the possibility of its utilization with other embryofetal tissues for invasive diagnosis orientation and anti-D immunoglobulin use only in cases of maternal-fetal incompatibility. Also, with an increase of this techniques sensitivity, fewer DNA amounts could be detected, which will certainly be an important step towards noninvasive fetal RhD diagnosis.
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Plata, Becerril Adriana. "PREPARACIÓN Y CARACTERIZACIÓN DE LIPOPROTEÍNAS DE ALTA DENSIDAD COMO TRANSPORTADORES DE RODAMINA PARA TERAPIA FOTODINÁMICA." Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2019. http://hdl.handle.net/20.500.11799/105207.
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Las lipoproteínas de alta densidad (HDL), participan en el transporte en reversa del colesterol, mecanismo mediante el cual suministran a las células del colesterol necesario para desempeñar sus funciones vitales.
Las células de cáncer tienen una alta demanda de colesterol y otros nutrientes, por lo que sobreexpresan el receptor SR-B1, encargado de internalizar el colesterol contenido en HDL a la célula. Valiéndose de este principio, se espera una alta afinidad de las células de cáncer por las lipoproteínas de alta densidad reconstituidas (rHDL) por lo que serían un buen vehículo para el transporte de fármacos.
La terapia fotodinámica (PDT) es un tratamiento emergente contra el cáncer que promete múltiples beneficios. Se basa en la administración de un fotosensibilizador (PS), una sustancia que, al ser irradiada a la longitud de onda adecuada, provoca daño a biomoléculas y muerte celular.
La presente investigación se centra en el desarrollo de un vehículo de administración de rHDL para las rodaminas 123, 6G y B; sustancias con potencial actividad fotosensibilizadora. La capacidad fotosensibilizadora de las rodaminas fue demostrada al irradiar una solución de ácido fólico + rodaminas que resultó en la disminución de la concentración del ácido fólico. Se determinó el coeficiente de partición octanol/agua de las rodaminas antes mencionadas, con el fin de predecir si podrían internalizarse en las nanopartículas de rHDL.
Se prepararon nanopartículas de rHDL vacías a las que se les determinó su espectro de absorción e infrarrojo, así como el tamaño de partícula mediante espectrometría UV-Vis, espectrometría IR y DLS respectivamente. Posteriormente, fueron preparadas NPs de rHDL cargadas con las rodaminas 123, 6G y B de las que se obtuvieron los espectros de absorbancia UV-vis con la finalidad de encontrar las bandas de las rodaminas, que demostraran que se encuentran dentro de las NPs.
Se realizó un ensayo in vitro en el que células de cáncer de la línea celular T-47D fueron administradas con rodaminas: Rod 123, Rod 6G y Rod B y alternativamente otras células fueron administradas con rHDL + rodaminas: rHDL-rod123, rHDL-rod6G y rHDL-rodB, encontrándose cualitativamente mediante microscopía de fluorescencia que las células que fueron administradas con rHDL-rodaminas cargaron una mayor cantidad del PS.PRODEP 2018 511-6/18-8981
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Evans, Rachael Yvonne. "The production of anti-idiotopic antibodies to monoclonal anti-RhD antibodies." Thesis, Lancaster University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274194.
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Stott, Lisa M. "Characterisation of the alloreactive T helper epitopes on the RhD protein." Thesis, University of Aberdeen, 2002. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU170746.
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The Rhesus (Rh) D antigen is important in transfusion medicine and is the major target in haemolytic disease of the newborn (HDN). The aims of this project were to characterise the helper-T (Th) cell response that drives anti-D alloantibody production in HDN as a first step towards developing an improved or alternative strategy to the current programme of prophylaxis, based on the manipulation the T-cell response. Peripheral blood mononuclear cells (PBMC) were obtained from 22 individuals, who had developed anti-RhD alloantibodies following natural or deliberate immunisation, and from 22 RhD negative and from 12 RhD positive control donors who had not been immunised with RhD. A panel of 69 overlapping synthetic 15-mer peptides, spanning the sequence of the RhD protein, was screed for the ability to stimulate recall proliferation and cytokine production from T-cells in cultures of the PBMC. T cells from all 22 of the alloimmunised donors proliferated in response to RhD peptides and typically multiple peptides were stimulatory. In contrast, only a few minor responses were observed in the control donors. RhD peptides 6, 13, 17, and 28 were identified as immunodominant peptides that stimulated proliferation in over 50% of the alloimmunised donors. Each of these peptides were promiscuous in their ability to stimulate T-cells from donors of the common HLA allotypes in this study. Each immunodominant peptide contains multiple core epitopes and multiple sets of MHC/TCR contacts. Preliminary findings indicate that neither peptides shorter than 15mer length nor analogues can be designed to boost or tolerise alloimmunised donors. The RhD peptides induced a complex pattern of cytokine production from alloreactive T cells. Both IFN-gamma and IL-4 could be produced to the RhD peptides indicative of a Th0 response. In addition, particular peptides elicited the production of the potentially inhibitory cytokines IL-10 or TGFb and not proliferation.
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Chen, Qing [Verfasser]. "Random survey for RHD alleles among D positive Europeans / Qing Chen." Ulm : Universität Ulm. Medizinische Fakultät, 2004. http://d-nb.info/1015471439/34.
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Lobo, Guilherme Antonio Rago [UNIFESP]. "O desfecho perinatal da aloimunização eritrocitária não-relacionada ao antígeno RhD." Universidade Federal de São Paulo (UNIFESP), 2007. http://repositorio.unifesp.br/handle/11600/23554.
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Previous issue date: 2007Objetivos: Analisar o desfecho perinatal da Aloimunização eritrocitária não-relacionada ao antígeno RhD. De forma complementar, confrontar os resultados perinatais com os da Aloimunização RhD e com aqueles de gestantes Rh- não-sensibilizadas. Método: Estudo observacional descritivo realizado no período de Janeiro de 2000 a Julho de 2005. Foram avaliadas 15 gestantes sensibilizadas por anticorpos não-D (grupo A), 55 grávidas Rhsensibilizadas pelo anti-D (grupo B) e 130 gestantes Rh- não-sensibilizadas (grupo controle C). Foram apurados os seguintes parâmetros relativos à gestante e ao recémnascido: título do anticorpo, alterações ultra-sonográficas ao longo do acompanhamento pré-natal, transfusão intra-uterina, via de parto, idade gestacional ao nascimento, peso ao nascimento, índice de Apgar no quinto minuto, hematócrito do recém-nascido, necessidade de transfusão e/ou exsanguino transfusão no período neonatal, tempo de internação no berçário, natimortalidade e mortalidade no período neonatal. Resultados: No grupo A encontramos sete gestantes sensibilizadas por anticorpos do sistema Lewis, três por anticorpos do sistema Kell, três por anticorpos relacionados ao sistema MNS e duas pelo sistema Diego. Título de anticorpo ≥ 1/16 foi encontrado em todas as pacientes do grupo B e em 27% do grupo A. As alterações ultra-sonográficas estiveram presentes de maneira semelhante entre as grávidas dos grupos A e B (20% e 25%). Transfusão intra-uterina, embora mais freqüente no grupo B, em relação ao grupo A (20% e 7%), não apresentou significância estatística. O parto cesáreo foi realizado de forma crescente nos grupos C, A e B (44%, 53% e 78%). O parto pré-termo teve maior incidência no grupo B em comparação aos grupos A e C (40%, 27% e 7%), assim como o baixo peso ao nascer (39%, 27% e 7%). Índice de Apgar < 7 no 5º minuto foi semelhante entre os três grupos. O hematócrito médio, obtido de sangue do cordão umbilical, foi significativamente maior entre os recém-nascidos do grupo A, em relação ao grupo B (43% e 40,5%). Transfusão e/ou exsanguino transfusão foram indicadas mais vezes nos infantes do grupo B em relação àqueles dos grupos A e C (69%, 14% e 1%). Internação prolongada no berçário (maior que três dias) foi mais encontrada também no grupo B, quando comparada aos grupos A e C ( 75%, 14% e 2%). Verificaram-se quatro óbitos intra-uterinos, um no grupo A, dois no grupo B e um no grupo C. Nenhum óbito foi registrado no período neonatal entre infantes dos grupos A e C, enquanto no grupo B, três recém-nascidos tiveram êxito letal. Conclusões: A Aloimunização eritrocitária não-relacionada ao antígeno D pode determinar quadro de Doença hemolítica perinatal grave, com necessidade de tratamento intra-uterino. Em comparação à Aloimunização RhD, no entanto, determina melhor desfecho perinatal, considerando-se o hematócrito ao nascimento, a necessidade de transfusão e/ou exsanguino transfusão no período neonatal, o tempo de internação no berçário e o decesso perinatal.
Objectives: Evaluate perinatal outcomes of non-D alloimmunization. Additionally to compare perinatal results with those of D alloimmunized pregnancies and RhD negative not sensitized. Methods: Descriptive observational study with a control group. The study involved 200 women examined between January 2000 and July 2005. Patients were divided in three groups: 15 non-D alloimmunized pregnant (group A), 55 D alloimmunized pregnant (group B) and 130 RhD negative women not sensitized (control group – C). Obstetric and neonatal variables analyzed were: antibody titer, ultrasound findings during pregnancy, intrauterine transfusion, mode and timing of delivery, birthweight, 5-minute Apgar score, neonatal hematocrit, need for neonatal transfusion or exchange transfusion, duration of neonatal stay, intrauterine and neonatal death. Results: Group A comprised 7 patients with Lewis sensitization, 3 with Kell sensitization, 3 with MNS sensitization and 2 with antibodies against Diego system antigens. Antibody titer ≥ 1/16 were seen in all group B patients and in 27% of group A pregnant. Abnormal ultrasound findings were similar between group A and B (20% and 25%). Intrauterine transfusion although more frequent in group B, compared to group A, did not reach statistically significance (20% e 7%). Rate of cesarean deliveries was crescent in C, A and B groups (44%, 53% and 78%). Prematurity was more incident in group B, compared to A and C groups (40%, 27% and 7%), and the same was found related to the low birthweight (39%, 27% e 7%). There were no significant differences regarding the 5-minute Apgar score between all groups. Mean neonatal hematocrit was higher in group B than in group A (43% and 40,5%). The need for neonatal transfusion or exchange transfusion was higher among group B infants, compared to A and C groups (69%, 14% and 1%). Neonatal stay was longer in group B newborn, in comparison to A and C groups (75%, 14% and 2%). There were 4 intrauterine deaths, one in group A, two in group B and one in group C. No death in the neonatal period was registered in group A and C infants while it occurred in three liveborns of group B. Conclusions: Non-D alloimmunization may cause hemolytic disease severe enough to require intrauterine treatment. Compared to D alloimmunization, yelds better perinatal results taking into consideration neonatal hematocrit, need for neonatal transfusion or exchange transfusion, duration of neonatal stay and perinatal mortality
BV UNIFESP: Teses e dissertações
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Pacheco, Cynthia Amaral Moura Sá. "Doença hemolítica perinatal Rhd: um problema de saúde pública no Brasil." Instituto Nacional de Saúde da Mulher e da Criança Fernandes Figueira, 2013. https://www.arca.fiocruz.br/handle/icict/7929.
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Previous issue date: 2013Fundação Oswaldo Cruz. Instituto Nacional de Saúde da Mulher, da Criança e do AdolescenteFernandes Figueira. Departamento de Ensino. Programa de Pós-Graduação em Saúde da Criança e da Mulher. Rio de Janeiro, RJ, Brasil.
Introdução: A Doença Hemolítica Perinatal RhD (DHPN-RhD) é decorrente da passagem transplacentária de anticorpos maternos anti Rh positivo causando hemólise no feto e recém-nascido. Este processo pode ser prevenido pela administração de imunoglobulina anti-Rh D, no entanto, quando instalada, é irreversível. Os pacientes afetados poderão desenvolver anemia e icterícia que se não tratadas adequadamente, levam a dano cerebral irreversível, clinicamente conhecido como Kernicterus ou morte. Apesar da existência de profilaxia adequada, a DHPN-RhD ainda é prevalente no Brasil, mas não é considerada para cálculo nos Estudos de Carga de Doença. Considerando que ela possa representar uma fração importante da morbidade e mortalidade perinatal e neonatal este trabalho propõe o cálculo da carga da DHPN-RhD no Brasil Objetivo: Calcular a Carga da DHPN-RhD no Brasil e Regiões do País Método: O indicador utilizado neste estudo foi o número de anos de vida perdidos ajustados por incapacidade DALY (DisabilityAdjusted Life Years). O número de DALY foi calculado a partir da soma de duas parcelas: Anos de Vida Perdidos por Morte Prematura (YLL -Years of Life Lost,) e os Anos de Vida Perdidos devido à Incapacidade (YLD - Years Lived with Disability. Os dados para o cálculo do YLL foram obtidos através do Sistema de Informação sobre Mortalidade (SIM/DATASUS). No processo de estimação do YLD, foram utilizados, como parâmetros clínicos epidemiológicos, os casos incidentes, a duração e o peso médio das incapacidades. O considerada foi de até 30 dias. Devido à gravidade do Kernicterus, considerou-se como duração 50% da expectativa de vida estimada para o País e para as macrorregiões. Para avaliar as estimativas dos pesos das incapacidades optou-se utilizar o peso 0,894 para os casos de DHPN-RhD sem sequelas e 0,459 para os casos de Kernicterus, considerando as sequelas neurológicas relacionadas ao quadro. Resultados: A DHPN-RhD possui as menores taxas de DALY em todas as regiões do País comparando com os outros eventos perinatais. As regiões Norte e Nordeste tiveram as maiores taxas para todos os eventos neonatais com exceção da DHPN-RhD cuja segunda maior taxa foi a da região Sul. Quando analisados o componente YLL, as maiores taxas estão nas regiões Norte e Nordeste e a menor no Sudeste. Em relação ao YLD, observa-se uma inversão em relação aos valores encontrados para o componente YLL, isto é, as maiores taxas foram aquelas das regiões Sudeste e Sul. Conclusão: Apesar de a Carga da DHPN-RhD no Brasil ser muito inferior aos outros eventos perinatais ele demonstra uma herança histórica de ausência de investimentos no Norte e Nordeste como demonstrado em nosso trabalho, onde o risco de morrer por DHPN-RhD é maior que nas regiões Sul e Sudeste. Assim, para o declínio da DHPN-RhD no nosso país há necessidade de melhorar a assistência perinatal e também de um reconhecimento político da contingência dessas desigualdades regionais e da necessidade de priorizar a profilaxia ao invés de tratamento.
Introduction: Rhesus Haemolytic Disease (RHD) occurs due passage of maternal antibodies anti RhD by placenta causing hemolysis in fetus and newborn. This can be prevented by administration of anti-Rh D immunoglobulin, however, when installed, is irreversible. Affected patients may develop anemia and jaundice which if not treated, lead to irreversible brain damage known as kernicterus or death. Despite the existence of appropriate prophylaxis to RhD-DHPN is still prevalent in Brazil, but is not considered for calculating the Burden of Disease Study. Whereas it may represent an important fraction of perinatal morbidity and mortality and neonatal this paper proposes calculation the burden of Rhesus Haemolytic Disease in Brazil Objective: To calculate burden of Rhesus Haemolytic Disease in Brazil and Macroregions Methods: The indicator used in this study was the number of years of life lost disability-adjusted DALY (Disability Adjusted Life Years). The number of DALYs was calculated from the sum of two components: Years of Life Lost to Premature Death (YLL-Years of Life Lost) and Years of Life Lost due to Disability (YLD - Years Lived with Disability. Data for the calculation of YLL was obtained through the Information System (SIM / DATASUL.) In the process of estimation of YLD were used as clinical epidemiological incident cases, the length and weight of disabilities. The number of incident cases calculated through analysis of the Hospital Information System of the Unified Health System (SIH-SUS). In the case of RhD without sequelae was considered the duration of up to 30 days due but to the severity of kernicterus it was considered as 50% of the duration estimated life expectancy. To evaluate the estimates of the weights of disabilities we use the weight to 0,894 cases of RHD without sequelae and 0.459 for cases of kernicterus considering neurological sequelae. Results: RHD has the lowest rates of DALYs in all regions of the country compared to other perinatal events. The North and Northeast had the highest rates for all events with the exception in the South were the rates RHD DALYS was the second highest. When analyzed the component YLL rates are the highest in the North and Northeast and the lowest rate in the Southeast. Regarding the YLD observed a reversal of the values found for the YLL component is the highest rates were those from Southeast and South Conclusion: Despite the burden of RhD Hemolytic Disease Perinatal in Brazil is much lower than the other perinatal events there is a historical legacy of lack of investment in the North and Northeast as demonstrated in our work where the risk of dying from DHPN-RhD is higher than in the South and Southeast. So for the decline of DHPN-RhD in our country there is a need to improve perinatal care and also a political recognition of the contingency of these regional inequalities and the need to prioritize the prevention rather than treatment.
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Nasr, Hosaam Hassan. "The effect of reconstituted high density lipoprotein (rHDL) infusion on patients with symptomatic carotid disease." Thesis, St George's, University of London, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604014.
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Background - Elevation of plasma HDL concentration reduces cardiovascular mortality and morbidity. HDLs have been shown to possess acute anti -inflammatory, anti -oxidant and anti -thrombotic properties. We hypothesise that HDL therapy can acutely alter local and systemic manifestations of plaque instability, Methods and Results - Forty patients with early symptomatic carotid disease were randomised to either receive reconstituted HDL (rI-IDL) - 40mg/kg (11=20), or placebo (11=20). Carotid endarterectomies (CEAs) were performed 24 hours later. Plaques were obtained intra-operatively and used for measurement of thrombomodulatory genes expression. Plasma samples were collected prior to the infusion, 24 and 48 hours later to measure changes in systemic markers of plaque instability. No significant differences were noted in thrombomodulatory genes expression between the two groups. Systemic levels of TF, MMP-9 and MCP-l were significantly reduced in the rHDL group. However, the effects on MMP-9 and MCP-I were abolished in the immediate post-operative period. Although rHDL did not affect plasma IL-6levcls 24 hours following the infusion, it prevented the significant postoperative elevation seen in the placebo group. A similar, but non-significant trend was demonstrated with CRP levels. Conclusion - A single infusion of rHDL can acutely alter plasma biomarkers associated with plaque instability and cardiovascular morbidity.
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Kacem, Narjess. "Détermination de la zygotie du gène RHD dans la population tunisienne : impacts des polymorphismes des "boîtes Rhésus" dans la pertinence des analyses moléculaires." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM5093/document.
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La prédiction de la zygotie à partir du génotype le plus probable en la comparant à la PCR-SSP, n’était pas fiable liée à la possibilité d’avoir d’autres génotypes possibles pour le même phénotype. En effet, la fréquence très proche de l’haplotype R0 et r dans la population tunisienne rend la déduction du génotype le plus probable très aléatoire. Dans un deuxième temps, l’évaluation de la méthode moléculaire la plus convenable à la détermination de la zygotie RHD a été réalisée par comparaison des trois techniques moléculaires (PCR-SSP, PCR-RFLP et Q-PCR) et par l’analyse des résultats discordants par séquençage du gène RHD et des « boîtes Rhésus ». L’analyse de 370 échantillons RH:1 à l'aide de ces trois tests moléculaires a montré que 81,9% des résultats étaient en concordance alors que 18,1% en discordance. L’analyse des cas discordants a montré que notre cohorte se compose de 193 sujets dizygotes et 145 hémizygotes et 32 dont la zygotie reste inconnue. Cette étude a révélé 19 nouveaux polymorphismes des « boîtes Rhésus » et a permis aussi de décrire trois nouveaux allèles RHD: RHD(Trp185Stop), RHD(Ala176Thr) et RHD(Ile342Ile). Cette étude a également mis en valeur l’hétérogénéité des « boîtes Rhésus » et la complexité des allèles RHD en décrivant les nouveaux polymorphismes obtenus, ce qui met en évidence les limites des approches moléculaires de la détermination de la zygotie. La Q-PCR a été la méthode la plus adaptée à la détermination de la zygotie, mais en raison des contraintes économiques locales, la PCR-RFLP pourrait être une alternative malgré l’hétérogénéité des « boîtes Rhésus » et la complexité du gène RHDDetermination of paternal RHD zygosity can help the clinician to assess the risk of HDN. It was determined initially by both assignment of the most probable genotype and PCR-SSP. The prediction of zygosity based on the most probable genotype was not reliable due to the possibility of other genotypes for the same phenotype. In fact, the frequencies of R0 and r haplotypes in the Tunisian population are approached and make the deduction of the most probable genotype very aleatory. Secondly, the evaluation of the most convenient molecular method for RHD zygosity determination was realized by comparison of three molecular techniques (PCR-SSP, PCR-RFLP and RQ-PCR) and analysis of discordant results by sequencing of the RHD gene and Rhesus boxes. Analysis of 370 RH:1 samples by these three molecular tests showed concordant results in 81.9% and discordant results in 18.1%. Molecular investigations revealed that our cohort consists of 193 dizygous and 145 hemizygous samples and 32 which zygosity remains unknown. This study revealed 19 novel Rhesus boxes polymorphisms, and described 3 novel RHD alleles: RHD(Trp185Stop), RHD(Ala176Thr) and RHD(Ile342Ile). This study also underlined Rhesus boxes heterogeneity and RHD alleles complexity by describing of new polymorphisms which showed the limits of molecular approaches for RHD zygosity determination. RQ-PCR is the most convenient method for first intension paternal RHD zygosity determination in Tunisians. However taking into account local economic constraints PCR-RFLP could be an alternative despite the Rhesus boxes heterogeneity and RHD complexity
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Ziza, Karen Nogueira Chinoca. "Determinação do genótipo RHD fetal no plasma materno: acurácia do teste semiautomatizado." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5139/tde-03022016-093418/.
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INTRODUÇÃO: A determinação do genótipo RHD fetal no plasma materno é um teste de diagnóstico pré-natal não invasivo oferecido a gestantes RhD negativo que apresentam potencial de sensibilização e/ou Doença Hemolítica Perinatal. Atualmente, este exame é realizado de rotina em diversos países, mas não no Brasil. A Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) oferece atendimento terciário a gestantes RhD negativo, com monitorização dos títulos de anticorpos irregulares, administração da imunoglobulina anti-D e/ou terapêutica fetal, quando necessários. OBJETIVO: Avaliar a acurácia do teste semiautomatizado para determinação do genótipo RHD fetal no plasma materno. METODOLOGIA: Foram coletadas prospectivamente amostras de sangue de 220 gestantes RhD negativo, com idade gestacional entre 8-28 semanas. O plasma foi obtido em no máximo 2 horas após a coleta, e uma alíquota de 1 mL foi submetida à extração de ácidos nucléicos no equipamento automatizado MagNA Pure Compact (Roche), empregando o kit Large Volume. O DNA extraído foi submetido a PCR em tempo real (Step One Plus - Applied Biosystems), usando o protocolo do grupo SAFE, que tem como alvos os éxons 5 e 7 do gene RHD. RESULTADOS: Ocorreu exclusão de 35 amostras devido a problemas pré-analíticos, aborto ou desconhecimento do fenótipo do recém-nascido. Entre as 185 amostras analisadas, 130 (70,2%) foram genotipadas como RHD+ e 55 (29,8%) RHD-. Os resultados obtidos foram comparados com a fenotipagem do cordão umbilical, e houve concordância completa (100%). Sete amostras exibiram amplificação exclusiva para o éxon 7. Essas amostras foram submetidas aos protocolos em PCR convencional, e PCR em tempo real específico para o pseudogene RHD. Ambos os ensaios apresentaram os mesmos resultados: cinco positivos e dois negativos. Nesses mesmos 7 casos, após extração da camada de leucócitos materna, os protocolos foram repetidos, e o resultado confirmou que cinco mães eram RHD. As duas amostras com resultado negativo foram submetidas ao protocolo Multiplex, envolvendo os éxons 3-9 do gene RHD, com resultados negativos, confirmando que as mães são verdadeiramente RHD- portanto o sinal do éxon 7 é provindo dos fetos que são D variantes. CONCLUSÃO: O método para a determinação do RHD fetal no plasma materno descrito demonstrou ser rápido, de fácil execução, alta precisão e reprodutível, além de indicar possíveis variantes RHD em nossa populaçãoBACKGROUND: Fetal RHD genotype determination in maternal plasma is a noninvasive prenatal diagnostic test performed in RhD negative pregnant women at risk of alloimmunization and/or Hemolytic Disease of Fetus and Newborn. Currently, this test is routinely performed in many countries but not in Brazil. The Department of Obstetrics at Hospital das Clínicas, São Paulo University Medical School provides tertiary antenatal care for RhD negative pregnant women including anti-D immunoglobulin administration, antibody levels monitoring and intrauterine treatment if necessary. AIMS: To validate the accuracy of a semi-automated test for fetal RHD genotype determination in maternal plasma. METHODS: Two-hundred and twenty blood samples were prospectively collected between 8 and 28 weeks of gestational age. Plasma processing was performed within 2 hours after blood collection, and nucleic acids were extracted from 1mL aliquots with an automated extraction platform (MagNA Pure Compact Roche) and the Large Volume kit. RHD gene exons 5 and 7 were amplified with real-time PCR (Step One Plus - Applied Biosystems) using the SAFE group protocol. RESULTS: Thirty-five samples were excluded due to pre-analytical problems, miscarriage and missing follow-up. In the remaining 185 samples, 130 (70.2%) were genotyped as RhD+ and 55 (29.8%) RhD-. Comparison with umbilical cord blood group phenotype showed 100% concordance. Seven samples showed amplification for exon 7 only. These were further investigated with conventional and real-time PCR with an specific protocol for RHD? pseudogene: 5 were positive and 2, negative. In these 7 cases, maternal buffy-coat DNA analysis also confirmed that 5 women were RHD?. In the remaining 2 cases, a multiplex protocol directed at RHD gene exons 3-9 confirmed that both mothers were truly RhD negative so exon 7 signal comes from the fetuses, further found to harbor D variants. CONCLUSION: The present study demonstrates that fetal RHD determination in maternal plasma is a fast, easy-to-perform and reproducible technique with high accuracy in our population. Moreover, it helps in the identification of possible RHD variants in our population
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Oyebamiji, Oyeleke. "The household economic impact of Rheumatic Heart Disease (RHD) in South Africa." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29377.
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Background: Rheumatic heart disease (RHD) remains a major public health concern in African countries due to the high rates of complications such as atrial fibrillation, stroke, infective endocarditis, and heart failure, all of which can result in premature death. In 2015, RHD was estimated to affect 33 million people globally and resulted in at least 320,000 deaths, nearly all of which were in low and middle-income countries. Comparing to other non-communicable diseases (NCDs), RHD imposes economic burden on households that if measures are not in place to mitigate this, it can impoverish such household. However, there are several literatures on the intergenerational economic consequences of other chronic diseases. But, there is no study regarding the household economic of RHD. This mini-dissertation sets out to estimate the household economic impact of RHD. Methods: This study was a follow-on study from the Global Rheumatic Heart Disease Registry (REMEDY), which was a multi-center, international, hospital-based prospective registry of patients with RHD. It was designed as a cohort study to document the disease characteristics and outcomes of individuals with RHD across many countries. We recruited participants in the REMEDY study who were resident in Cape Town and received care at Groote Schuur Hospital (GSH). This study made use of patient and household member surveys to estimate the economic consequences of RHD among households in which REMEDY participants reside. REMEDY registry participants (index cases), their caregivers, and other household members were considered as respondents. 100 REMEDY participants receiving care at GSH was sampled. This sample size was chosen to balance feasibility and precision and to align with a parallel study of the cost of RHD to the health system that aimed to sample medical records from the same 100 REMEDY participants. Patient and household data collection was carried out between September 2017 to December 2017. Direct costs, indirect costs, and the downstream economic behaviors (coping strategies) that lead to medical impoverishment and other consequences were estimated. Cost of illness (COI) was used to assess the effect of ill-health and health-related expenditure on the consumption possibilities of households. Direct costs comprise both medical and nonmedical costs, which may include both the financial cost of resources as well as opportunity costs (e.g., of capital items). Human capital approach was used to calculate indirect cost. Implicit in the human capital approach is the assumption that changes in health status of household members can be reflected by losses in productivity, and losses in income generation. Productivity losses was estimated using the new South Africa minimum wage rate per month as proxy. Coping was estimated with the direct costs (e.g., borrowing from friends or relatives, or taking out formal loans) or indirect costs (e.g., intra-household labor substitution) and can be cost prevention strategies (e.g., ignoring illness, non-treatment) to cost management strategies (e.g., borrowing, selling assets, or labor substitution). Economic costs were valued in United State dollar (USD) converted from South African rand (ZAR) in 2017. Results: Direct medical cost was estimated to ZAR 0, because all patients were exempt from medical fees. Total direct non-medical cost for outpatient and inpatient visits was estimated to be ZAR 27,000 (USD 2000) and 29,000 (USD 2200) (respectively) over 302 and 74 encounters (respectively), an average of ZAR 270 (USD 20) and ZAR 290 (USD 22) per patient (respectively). Indirect costs incurred over the 302 outpatient encounters and 74 hospital admissions were estimated to be ZAR 41,000 (USD 3100) and ZAR 26,000 (USD 1900) (respectively), an average of ZAR 410 (USD 31) and ZAR 260 (USD 19) per patient. Direct cost had a very high impact on the household and they were compelled to adopt coping. Households observed in the study recorded that seventeen percent of households took out loans at an average of ZAR 1200 (USD 91) per loan (range ZAR 100 to ZAR 7000) (range USD 7 to 500). Fifteen percent received financial gifts at an average of ZAR 800 (USD 61) per gift. Two percent sold assets valued at ZAR 5600 (USD 120) on average. Five percent engaged in multiple coping strategies. Also, HH had to cope with indirect cost of illness as 15% of household caregivers changed jobs and 10% worked extra hours. About 4% of household members dropped out of school. Four percent adopted more than one coping strategy. A considerable share of participants reported that they had reduced education to take care of the affected patient. Most of the caregivers of patients with RHD were spouses and children, and 6 % were heads of household. The total cost of RHD to the average affected household is valued at about ZAR 1600 annually. In total, the overall annual economic impact of RHD in this sample of 100 households affected by RHD was estimated at ZAR 160,000 (USD 12200) (ZAR 1600 per household) (USD 120), representing 4.4% of annual household income or 4.9% of annual household expenditure patient spending that exceeded 10% threshold was estimated to be 8% and increasing the threshold to 40 % of non- food expenditure reduced the prevalence of catastrophic spending to 4%. Conclusions: The economic impact of RHD in South Africa is substantial despite government efforts to provide free care. The total cost of RHD to the average affected household is valued at about ZAR 1600 annually. A broader and more robust range of social policies will be required to mitigate non-medical and indirect costs and reduce distortions in household economic activity.
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Meshi, Abdullah Ahmed. "Characterisation of humoral immune responses to Rhd blood group antigen-derived synthetic peptides." Thesis, University of Aberdeen, 2012. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=186873.
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The aim of this project was to characterise the humoral immune responses to RhD-derived synthetic peptides as a first step towards developing alternative peptide immunogens to replace RBC in immunising donors for anti-D IgG antibody production for clinical use. In the first part, 4 peptides (Dp6, Dp13, Dp17, and Dp28) containing Th-cell epitopes on the RhD protein were used to stimulate PBMC from 2 D-alloimmunised donors in vitro. A mixture of the four peptides was also utilised to boost HLA-DR15 transgenic mice previously immunised with purified RhD protein. The ability of the four peptides to boost anti-D titre significantly varied between the two donors, with a maximum 3-fold increase in anti-D titre induced by Dp17 in donor 2. The mouse antibody response to peptide boosting was also variable, with 4 of the 6 (66.7%) peptide-boosted DR15 mice demonstrating positive changes in anti-RhD antibody levels. The findings from the in vitro and mice studies demonstrated that these four peptides had the potential to boost anti-D titres in D-alloimmunised donors. In the second part of this study, an alternative approach to designing a totally synthetic peptide immunogen was investigated. An RhD mimotope (DM4) was selected from a set of previously identified RhD mimotopes, and its antigenic mimicry for the D antigen was verified. The DM4 peptide was coupled with the Dp6 peptide as a Th-cell epitope, to construct a chimeric T-B peptide immunogen. The immunogenicity of the T-B and DM4 peptides were evaluated in DR15-transgenic mice. Both peptides were able to induce significant DM4-specific IgG antibodies. The immunogenicity of the DM4 was significantly augmented by colinear coupling to the Dp6 peptide. The immunogenic mimicry of the DM4 peptide for the D antigen was examined through the ability of mouse anti-DM4 antibodies to recognise human D antigen on D-positive RBC. However, these antibodies appeared to recognise D antigen non-specifically, reacting with all tested human RBC regardless of their D phenotypes.
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Finning, Kirstin M. "Prediction of fetal RhD blood group status using fetal genetic material in maternal blood." Thesis, University of the West of England, Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275889.
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Harkness, Mairi. "Policy and practice concerning women with an RhD negative blood type : a midwifery perspective." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/9625.
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In May 2002 the National Institute for Clinical Excellence (NICE) made the recommendation that all pregnant women with an RhD negative blood type should be offered routine antenatal anti-D immunoglobulin (Ig) prophylaxis (RAADP). Midwives were the key professional group who would be involved in administration of anti-D Ig and yet they had little input to formation of policy and contributed little to the evidence base that informs policy and practice. A midwifery perspective is however important and relevant, and forms the basis of this work. The thesis comprises three distinct, but related, pieces of research: a survey conducted in 2005 to determine implementation of RAADP at UK maternity units; secondary analysis of anti-D Ig errors involving midwives that were reported to the Serious Hazards of Transfusion (SHOT) scheme in 2007/8; and focus group interviews conducted in 2010 to explore midwives’ views on issues that impact the care provided for women with an RhD negative blood type. The aim of the RAADP survey was to establish current {2005} policy in the United Kingdom in relation to the NICE recommendation for RAADP (NICE, 2002). The survey formed the foundation on which to build the thesis by determining that by 2005 RAADP had become an integral aspect of maternity care within the UK. However it also found that there were significant variations within local policies and among the information that was provided to pregnant women and healthcare professionals. The aim of the survey was to determine implementation of policy and not to explain findings, raising important questions which were used to inform the subsequent research. The second piece of research was secondary analysis of existing anti-D Ig error reports collated by SHOT. The analysis was unique in that it included only those errors involving midwives. The findings highlight both individual and organisational impact on errors, building on the findings of the RAADP survey. The research identified proximal errors, trigger events and fallible practices providing a framework within which the common pathways to error involving anti-D Ig can be understood. This will allow midwives to better understand and improve the care they provide. This piece of research also raised further questions about midwifery practice and those questions informed the focus group research. The focus group research aimed to consolidate the findings of the previous research by gaining direct input from midwives. Two focus group interviews were held, with clinical midwives as participants. The research found that the midwives and the organisations within which they worked provided care in line with policy and procedure at the apparent expense of a woman centred approach. This appeared to be linked to the midwives’ understanding of their responsibility, accountability and the education and information that underpinned the care they provided. The other important finding from the focus group research was that the midwives regarded RAADP as a less important intervention than they did anti-D Ig given following a potentially sensitising event (PSE) during pregnancy or given following delivery. When considered as a whole body of work, this research provides unique and valuable insight to midwifery involvement in the care of women with an RhD negative blood type. The research highlights the challenge of achieving government objectives for individualised, woman centred care within the present framework of clinical governance and evidence based care. In doing so it also raises questions about how individual midwives and the midwifery profession have engaged with medical colleagues and policy makers to maintain a midwifery context to the care they provide. Although the research findings relate to care provided for women with an RhD negative blood type the findings are pertinent to other aspects midwifery practice, particularly those originating within the medical profession that are now a routine part of midwifery care.
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Tezza, Lucianna Corrêa. "Estudo das variantes RHD em pacientes portadores da Doença Falciforme do Estado do Amazonas, Brasil." Universidade Federal do Amazonas, 2014. http://tede.ufam.edu.br/handle/tede/5172.
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FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas
Introduction:Studies have demonstrated the presence of RHD variants in sickle cell patients, resulting in subsequent alloimuzation, because of the Rh protein having structural function in membranes of these cells, other factors derived from these polymorphisms may impact on the length of life of the erythrocyte. The frequency of RHD variants is not yet known in sickle cell patients in the state of Amazonas and if there the possibility of association between these variants and blood transfusion in these individuals. Objective: Our aim was to investigate the variants of RHD in sickle cell patients in the State of Amazonas Materials and methods: We performed phenotyping of samples from patients with sickle cell disease by hemagglutination tube method using the reagent anti-D IgG clone MS201 and anti-D IgM clone MS26. The Multiplex PCR genotyping method was performed for characterization RHD regions of the Intron 4 and exon 7 and the exons 3, 4, 5, 6, 7 and 9 for the characterization of vari ant RhD.The statistical method of Chi Square was used for analysis of retrospective information on the number of transfusions and the presence of RhD variants. Results: We analyzed 128 samples, of which 45 (35.15%) showed discrepant results in serology for detec tion of RhD antigen and 12 (9.37%) patients with RhD variants. However 03 of these showed no discrepancies in RhD serology. While 33 discrepant samples in serological test s were not characterized as RhD variant. Among the variants, 07 (58.33%) were characterized as DVa, where such individuals were concentrated up to 32 RhD positive red cells without developing anti-RhD, 01 (8.33%) DFR presenting the frequency of transfusion 18 concentrated RhD positive red cells also without the presence of anti-RhD and 04 (33.33%) samples classified as indeterminate, and 2 of these patients had alloimmunization by anti-RhD. Discussion: Our results demonstrate that not all discrepancies in serological tests is indicative of variant RhD and that these results can be found 4 crosses for two reagents. The DVa variant was more frequent in our sickle cell patients and this is not associated with anti-RhD alloimmunization by patients with multiple transfusions in RhD positive red blood cells, thus contrasting with the frequency of DIIIa found in these type of patients studied in other regions of Brazil and associated with increased risk of alloimmunization. Conclusion: In conclusion, we observed that molecular biology tests are needed to detect the RHD gene. The variations DVa patients may not develop anti-D when transfused with RhD-positive erythrocytes. We found indications that the presence of RhD variants are not associated with the need for transfusions in patients with sickle cell disease.
Introdução: Estudos têm demonstrado a presença de variantes RHD em pacientes falciforme, resultando em aloimunizações subsequentes. Em razão da proteína Rh ter função estrutural na membrana destas Células, outros fatores derivados destes polimorfismos podem impactar na diminuição do tempo de vida do eritrócito. A frequência de variantes RHD ainda não é conhecida, nos pacientes falcêmicos do Estado do Amazonas e nem se há uma possível associação entre estas variantes e a transfusão sanguínea nestes indivíduos. Objetivo: Nosso objetivo foi investigar a as variantes do RHD em pacientes falciformes do Estado do Amazonas Casuísticae métodos: Pacientes falciformes atendidos no Hemocentro do Amazonas, nos quais realizamos a fenotipagem RhD, pelo método de hemaglutinação em tubo, utilizando reagentes anti-RhD IgG clone MS201 e IgM clone MS26 e genotipagem pelo método PCR multiplex para a caracterização de regiões do Intron 4 e exon 7 do gene RHD e outra PCR multiplex para detecção de regiões dos exons3, 4, 5, 6, 7 e 9 para caracterização de variantes RhD. O método estatístico do Qui Quadrado, foi utilizado para análise das informações retrospectivas do número de transfusões e a presença de variantes RhD. Resultados: Foram estudadas 128 amostras, das quais encontramos 45 (35,15%) com resultados discrepantesna sorologia para detecção do antígeno RhD e ainda 12 (9,37%) pacientes com RhD variantes, mas que 03 destes, não apresentaram discrepâncias na sorologia RhD. Ao passo que 33 amostras discrepantes nos testes sorológicos não foram caracterizadas como RhD variante. Dentre as variantes, 07 (5,33%), foram caracterizadas como DVa, em que tais indivíduos receberam até 32 concentrados de hemácias RhD positivo em desenvolver anti-RhD, 01 (8,33%) DFR apresentando a frequência de transfusão de 18 concentrados de hemácias RhD positivo tambémsem presença de anti-RhD e de 04 (33,33%) amostras que classificamos como indeterminados, sendo que 2 (50%) dos pacientes considerados indeterminados, apresentaram alo imunização por anticorpo anti-RhD. Discussão: Nossos resultados demonstram que nem toda discrepância no teste sorológico é indicativo de RhD variante e que estes podem ser encontrados mesmos resultados 4 cruzes nos dois reagentes utilizados. A variante DVa foi a mais frequente em nossos pacientes falciformes não estando associada à aloimunizaçãopor anti-RhD em pacientes politransfundidos com hemácias RhD positivo, contrastando assim com a frequência de DIIIa encontrada nestes tipo de pacientes estudados em outras regiões do Brasil e associada ao aumento de risco de aloimunização. Conclusão: Diante dos nossos resultados, observ amos que testes de biologia molecular são necessários para a detecção do gene RHD e ainda que pacientes com variantes DVa, podem não desenvolver anticorpo anti-D quando transfundidos com hemácias RhD positivo. Encontramos indicativos de que presença de variantes RhD caracterizadas nas amostras estudadas, não estão associadas à necessidade de transfusões em pacientes portadores da doença falciforme.
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Frohmajer, Alexander [Verfasser]. "Häufigkeit nicht-funktionaler Allele des RHD-Gens und Ursachen der fehlenden Antigen-Expression / Alexander Frohmajer." Ulm : Universität Ulm. Medizinische Fakultät, 1999. http://d-nb.info/1015269206/34.
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Overton, Timothy Graeme. "Minimally invasive prenatal diagnosis." Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/7869.
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St-Amour, Isabelle. "Utilisation de banque combinatoire d'anticorps phagiques afin de modifier la réactivité d'un anticorps dirigé contre l'antigène RHD." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0016/MQ49047.pdf.
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Akbulut, Derya. "Survival Modelling Approach To Time To First Claim And Actuarial Premium Calculation." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613113/index.pdf.
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Health problems of the human beings in a society are one of the main components of the social security systems due to the dimension of the financial burden it might bring on individuals, employers, insurance companies and governments. Morbidity measures, such as incidence and prevalence of a specific disease in a certain population enable researchers to estimate for individuals the probability of being diagnosed or being prone to the diseases. This information is usually not tractable because of the non-availability of the convenient data or recordings for many countries as well as Turkey. Even if it is available, it is commonly limited with largely varying characteristics about the type and coverage of the diseases. In this regard, the pattern that a population follows for an acute disease may not be the same for chronic diseases. Having those indicators determined for a group of insureds will enable underwriters to have more profitable and economical premium calculation and precision on required reserve estimation.
v
Based on their characteristics such as acute or chronic behaviour, the gender, and the location of residency of people, the diseases show different behaviour on their occurrences. From the insurer
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Hellebo, Assegid Getahun. "The Economic Impact of Rheumatic Heart Disease (RHD) on the Health System of South Africa. A Cost of Illness Study." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29245.
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Background
Rheumatic Heart Disease (RHD) is a disease of poverty that is neglected in developing countries. The consequences of RHD are increasingly becoming huge economic burden to the health system and consecutively the government. Despite RHD being preventable, most of the RHD related deaths happen in children and working age adults where the economic burden of premature death is high. Several strategies have been suggested to advance the escalation of disease severity in order to avoid medical cost including cost of surgery. However, lack of adequate evidence regarding the cost of treating RHD has hindered the needed decisions and interventions to prevent RHD related death. The main objective of this study was to evaluate the utilization of resources and quantify the annual average total cost related to RHD in a tertiary hospital in the Western Cape, South Africa.
Methods
A mixture of ingredients and step-down costing approaches were used to estimate the annual cost of RHD care from health system perspective. All costs were estimated in 2017 (base year) South African Rand (ZAR) and 3% discount rate in order to allow depreciation and opportunity cost. Data on service utilization rates were collected using a randomly selected sample of 100 patient medical records from the Global Rheumatic Heart Disease Registry (the REMEDY study), a registry of individuals living with RHD. Patient-level clinical data, including, prices and quantities of medications and laboratory tests, were collected from Groote Schuur Hospital (GSH). Step-down costing was used to estimate provider time costs and all other facility costs such as overheads. REMEDY and GSH data were aggregated to estimate the total annual costs of RHD care at GSH and the average annual per-patient cost among REMEDY participants. One-way univariate sensitivity analysis was conducted to deal with uncertainty.
Results
The total cost of RHD care at GSH was estimated at $2, 238, 294 (ZAR 27 million) in 2017, with surgery costs accounting for 65% of total costs. Per-patient average annual costs, which included outpatient care, cardiac medical and intensive care unit (ICU) care, cardiac catheterisation lab procedures, and heart valve surgery, was estimated at $4, 311 (ZAR 52, 000) per-patient annually. The cost of medications and consumables related to cardiac catheterisation and heart valve surgery were the main cost drivers.
Conclusions
RHD care consumes a significant level of tertiary hospital resources in South Africa, with annual perpatient costs much higher than many other non-communicable and infectious diseases. This analysis supports the scaling up of primary and secondary prevention programmes at primary health centres in order to reduce the future burden on tertiary services. The study may also inform resource allocation efforts related to RHD at tertiary centres and provide cost estimates for future studies of intervention cost-effectiveness.
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Albuquerque, Sérgio Roberto Lopes. "Estudo das associações entre os sistemas ABO, Duffy, antígenos RhD e a malária vivax em habitantes do Estado do Amazonas, Brasil." Universidade Federal do Amazonas, 2009. http://tede.ufam.edu.br/handle/tede/3111.
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Previous issue date: 2009-02-27Fundação de Amparo à Pesquisa do Estado do Amazonas
A malária é a mais importante doença parasitária do mundo, tendo exercido um forte efeito na evolução humana com um crescente corpo de evidências indicando que tanto o risco de adquirir esta infecção, quanto o de desenvolver severas complicações, tem sido determinado por fatores genéticos do hospedeiro e do parasito infectante. Isolados selvagens de parasitas de malária tem mostrado uma maior variabilidade para invadir hemácias humanas quando comparados com os cultivados em laboratórios, mostrando que em áreas endêmicas, estes podem ter desenvolvido diferentes habilidades para invadir particulares tipos de hemácias. Existem na literatura, resultados controversos quanto a associação entre o sistema ABO, antígenos Rh e a malária vivax, porém já foi bem demonstrada a importância da glicoproteína eritrocitária Duffy na invasão de hemácias humanas por merozoítos de Plasmodium vivax, entretanto ainda sendo pouco conhecido se mutações nesta glicoproteína podem estar associadas à frequência de infecção do P. vivax ou na densidade parasitária da malária vivax. Neste estudo investigamos associações entre o sistema sanguíneo ABO, antígeno RhD, as mutações da proteína Duffy (125 G>A (FYA/FYB) 265 C>T e 298 G>A (antígeno FyX) e do promotor GATA box, -33(T>C),) e a malária vivax, em habitantes do Estado do Amazonas, Brasil. Neste estudo, tanto a identificação do P. vivax, como a verificação das densidades parasitárias na malária vivax, foi determinada por testes microscópicos e leucometria em 497 pacientes infectados, nos quais foram realizadas fenotipagens dos sistemas ABO, Duffy antígeno RhD pela técnica da hemaglutinação, assim como as genotipagens do sistema sanguíneo Duffy pela técnica da PCR/RFLP. As possíveis associações entre as frequências encontradas dos sistemas sanguíneos citados e a malária vivax foram analisadas através do teste qui quadrado, assim como as possíveis associações das genotipagens Duffy com o nível de densidades parasitárias encontradas foram analisadas através do teste de kruskal wallis. Nossos dados mostraram, que a presença do antígeno A, genótipos FYA/FYB-33 e FYB/FYB-33 pode ser uma vantagem seletiva na população, reduzindo a taxa de infecção pelo P. vivax nesta região, porém sem estarem associados ao nível de densidade parasitária das infecções de malária. Não encontramos associação entre o antígeno RhD e a susceptibilidade ao P. vivax, no entanto os genótipos FYA/FYB, FYA/FYA mostraram-se associados ao aumento da frequência de infecção pelo P. vivax na região estudada. Os genótipos FYB/FYX e FYA/ FYX não mostraram-se associados à frequência de infecção pelo P. vivax, mas sim aos baixos níveis de densidades parasitárias encontrada entre os pacientes infectados com este genótipo. Reportamos, ainda, neste estudo, indivíduos com o genótipo FYB-33/FYB-33 com antecedentes de malária vivax. Estes resultados sugerem que, em regiões endêmicas de malária, pode estar havendo adaptações naturais tanto quanto ao surgimento de mecanismos parciais de defesa contra o Plasmodium vivax distintos dos já descritos em descendentes africanos como adaptações que podem estar também levando a um aumento a susceptibilidade a este tipo de malária.
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Zhu, Lin. "Structural studies of HDL and applications of EM on membrane proteins." Doctoral thesis, KTH, Strukturell bioteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-204045.
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A large number of proteins interact with biological membranes, either integrated in the membrane (PepTSo2), embedded on a membrane surface (5-lipoxygenase) or encircling a cutout of lipid bilayer (apolipoprotein1 (apoA-I). They function as transporters, receptors or biocatalysts in cellular processes like inflammation or cholesterol transport which are touched upon here. Malfunction of specific membrane proteins are the cause for several diseases or disorders. Knowledge of protein structure supports understanding of its mechanism of function. Here, transmission electron microscopy (TEM) was used for structure determination. To obtain structure information to high resolution for membrane proteins, normally surrounded by lipids, demands specific methods and materials for stabilization. Stabilized in detergent the structure of the bacterial transporter PepTSo2 was shown to form a tetramer even bound to substrate. However, with a protein based stabilizer, Salipro, the structure of PepTSo2 could be determined to high resolution. High density lipoprotein (HDL) in blood plasma, involved in the removal of cholesterol from peripheral tissues, have a central role in cardiovascular function, metabolic syndrome and diabetes. The HDL-particle is composed of two copies of ApoA1 and around hundred lipid molecules. From TEM data, for the first time the clearly discoidal shape could be shown by 3-dimendional reconstructions. These were used for modelling the ApoA1 protein dimer by a "biased fitting" procedure. The results indicate how ApoA1 folds around a lipid bilayer in a disc-shaped structure. Modified HDL called nanodiscs were here used to show the Ca2+ dependent binding of 5-lipoxygenase on the nanodisc bilayer and thereby increased production of the inflammatory mediator leukotrieneA4. Dimerization of 5-lipoxygenase inactivates these functions.QC 20170323