The clinical manifestations of hemolytic disease of the fetus and newborn mediated by anti-K, an antibody of the Kell blood group system, are distinguishable from the classical form of the disease. Affected fetuses have low numbers of circulating reticulocytes and antibody titers and bilirubin levels are not reliable predictors of anemia. These observations suggest that antibodies to Kell glycoprotein lead to anemia through suppression of erythropoiesis. This study established a liquid erythroid progenitor cell culture model in which to perform analyses on the mechanism of the suppressive growth effect of anti-Kell glycoprotein. Using this culture model, this study demonstrated the requirement for co-ligation of Kell glycoprotein by a bivalent antibody for growth suppression. The absence of markers of apoptosis in cell cultures treated with anti-Kell glycoprotein suggests that the mechanism of growth suppression is distinct from programmed cell death and necrosis. Furthermore, this growth suppression cannot be rescued by erythropoietin.

The clinical manifestations of hemolytic disease of the fetus and newborn mediated by anti-K, an antibody of the Kell blood group system, are distinguishable from the classical form of the disease. Affected fetuses have low numbers of circulating reticulocytes and antibody titers and bilirubin levels are not reliable predictors of anemia. These observations suggest that antibodies to Kell glycoprotein lead to anemia through suppression of erythropoiesis. This study established a liquid erythroid progenitor cell culture model in which to perform analyses on the mechanism of the suppressive growth effect of anti-Kell glycoprotein. Using this culture model, this study demonstrated the requirement for co-ligation of Kell glycoprotein by a bivalent antibody for growth suppression. The absence of markers of apoptosis in cell cultures treated with anti-Kell glycoprotein suggests that the mechanism of growth suppression is distinct from programmed cell death and necrosis. Furthermore, this growth suppression cannot be rescued by erythropoietin.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Objetivos: obter o perfil epidemiolÃgico e resultados perinatais de pacientes com diagnÃstico de hipertensÃo na gravidez. Analisar a hipertensÃo grave, presente nas patologias prÃ-eclÃmpsia grave, prÃ-eclÃmpsia superposta à hipertensÃo crÃnica, sÃndrome HELLP e eclÃmpsia, como fator de risco para complicaÃÃes maternas e neonatais em relaÃÃo a sÃndromes hipertensivas menos graves como prÃ-eclÃmpsia leve, hipertensÃo crÃnica e hipertensÃo gestacional. Sujeitos e mÃtodos: realizou-se estudo transversal na Maternidade-Escola Assis Chateaubriand entre junho de 2007 e agosto de 2008 com 201 pacientes com sÃndromes hipertensivas na gravidez. Agruparam-se pacientes com sÃndromes hipertensivas mais graves e seus desfechos perinatais usando o teste do qui-quadrado e seguiu-se anÃlise comparativa de suas caracterÃsticas sÃcio-demogrÃficas e obstÃtricas e resultados perinatais com mulheres com sÃndromes hipertensivas menos graves. Para mensurar a magnitude do risco foi calculado o odds ratio. Resultados: observaram-se 81,6% de pacientes pertencentes ao grupo da hipertensÃo mais grave, sendo 52,7% de prÃ-eclÃmpsia grave. As pacientes nulÃparas representaram 47%, sobrepeso 41% e obesidade 38%. Encontrou-se 44,2% de prematuridade, 37% recÃm-nascidos com peso abaixo de 2.500g e taxa de 65 Ãbitos por mil nascidos vivos. A anÃlise comparativa das caracterÃsticas das mulheres e resultados perinatais em sÃndromes hipertensivas graves em relaÃÃo as menos graves nÃo mostrou associaÃÃo significativa pelo odds ratio. ConclusÃo: o perfil das mulheres com sÃndromes hipertensivas graves foi similar ao de pacientes com quadros menos graves. Destacaram-se alta incidÃncia de prÃ-eclÃmpsia grave, sobrepeso e obesidade e altas taxas de prematuridade e de Ãbito neonatal. NÃo foi observada diferenÃa entre o comprometimento neonatal conforme os grupos de sÃndromes. / Objectives: To obtain epidemiological profile and perinatal outcome of patients diagnosed with hypertension in pregnancy. To analyze the severe hypertension, present in the pathologies pre-eclampsia, preeclampsia superimposed on chronic hypertension, HELLP syndrome and eclampsia as a risk factor for maternal and neonatal complications for hypertensive disorders and less severe mild preeclampsia, chronic hypertension and gestational hypertension. Subjects and methods: cross-sectional study was carried out in Maternidade Escola Assis Chateaubriand between June 2007 and August 2008 with 201 patients with hypertensive disorders in pregnancy. Patients with more severe hypertensive disorders and their perinatal outcomes were grouped using the chi-square test and followed up a comparative analysis of their socio-demographic characteristics and obstetric and perinatal outcomes of women with less severe disorders. To measure the magnitude of risk was calculated odds ratio. Results: there were 81.6% of patients in the group of more severe hypertension, and 52.7% of pre-eclampsia. The nulliparous patients accounted for 47%, 41% overweight and obesity 38%. It was found 44.2% of preterm births, 37% of newborns weighing less than 2500g and the rate of 65 deaths per thousand live births. The comparative analysis of characteristics of women and perinatal outcome in severe hypertensive disorders in relation to less serious showed no significant association by odds ratio. Conclusions: The profile of women with severe hypertensive disorders was similar to patients with less severe disorders. Of note is the high incidence of severe preeclampsia, overweight and obesity and high rates of prematurity and neonatal deaths. No difference was observed between the impairment groups as neonatal syndromes.

Made available in DSpace on 2014-09-09T12:22:45Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 69594.pdf: 1287197 bytes, checksum: 097f898f1364f075660a2a3257570c38 (MD5) Previous issue date: 2013 / Fundação Oswaldo Cruz. Instituto Nacional de Saúde da Mulher, da Criança e do Adolescente Fernandes Figueira. Departamento de Ensino. Programa de Pós-Graduação em Saúde da Criança e da Mulher. Rio de Janeiro, RJ, Brasil. / Objetivo: Identificar fatores de risco associados à necessidade de exsanguíneotransfusão (EXT) em gestações acometidas por doença hemolítica perinatal (DHPN) e avaliar a influência da terapêutica aplicada. Métodos: Foi realizado estudo de coorte e analisados 124 casos referentes a nascimentos de crianças com DHPN no período de abril de 2006 a junho de 2009, cujo parto ocorreu no Instituto Fernandes Figueira. Dados da história materna, pré-natal, parto e recém-nascido foram avaliados quanto a sua relação com a necessidade de transfusão intrauterina (TIU) e com o desfecho grave da doença, definido por EXT. Resultados: Paridade (RR:1,22; IC:1,00-1,49), história de filhos com doença (RR:3,21; IC:1,27-7,99) e hidropisia fetal (RR:1,86; IC:1,11-3,11) são fatores de risco importantes para a necessidade de TIU. Realização de TIU (RR:1,82; IC:1,12-2,97), parto normal (RR:0,53; IC:0,30-0,93), icterícia (RR:2,31; IC: 1,46-3,68), nível de hematócrito ao nascimento (RR:0,95; IC:0,93-0,98), bilirrubina total máxima durante a internação (RR:1,23; IC:1,16-1,31), tempo de fototerapia (RR:0,90; IC:0,85-0,95) e tempo total de internação (RR:097; IC:0,95-0,99), são variáveis que estabelecem relação independente e estatisticamente significativa com o desfecho de gravidade. A necessidade de EXT após TIU difere entre fetos menos graves (RR: 1,29; IC:0,94-1,77) e mais graves (RR: 1,61; IC:1,11-2,34). Conclusão: A identificação de fatores de risco é possível e importante para o cuidado do recém-nascido no período neonatal precoce acometido por DHPN. O impacto da terapêutica no desfecho neonatal varia de acordo com a gravidade no momento do diagnóstico. / Objective : To identify the major risk factors related to exchange transfusion (EXT) in pregnancies afflicted with hemolytic disease of the fetus and newborn (HDFN) and to evaluate the influence of applied therapy . Methods: A cohort study of 124 infants born with HDFN between A pril 2006 and June 2009 at the Fernandes Figuei ra National Institute . Data on maternal history, prenatal care, delivery and neonatal paramet ers were subjected to analysis to de termine their relationship with the need for i ntrauterine transfusion (IUT) du ring prenatal care and severe disease outcome, represented by EXT. Results: Parity (RR:1,22; C I :1,00 - 1,49) , obstetric history related to HDFN (RR:3,21; C I :1,27 - 7,99) and hydrops fetalis (RR:1,86; C I :1,11 - 3,11) are important risk factors related with the need for IUT. The need for IUT (RR:1,82; C I :1,12 - 2,97), vaginal delivery (RR:0,53; C I :0,30 - 0,93), jaundice (RR:2,31; C I : 1,46 - 3,68), hematocrit level at birth (RR:0,95; C I :0,93 - 0,98), peak serum bilirubin leve ls during hospitalization (RR:1,23; C I :1,16 - 1,31), duration of phototherapy (RR:0,90; CI:0,85 - 0,95) and total duration of hospital stay (RR:097; C I :0,95 - 0,99 ) were the variables found to establish an independent and statistically significant relationship w ith severe outcome. The need for EXT after IUT was different between fetus with less severe disease (RR: 1,29; C I :0,94 - 1,77) and more severe disease (RR: 1,61; C I :1,11 - 2,34). Conclusion: To identify risk factors is possible and important in early neonatal assistance of newborn afflicted with HDFN. The impact of therapy on the neonatal outcome depends on severity of the disease at the moment of diagnosis.

Une méthode de réaction de polymérisation en chaîne en temps réel (t-PCR), permettant de déterminer dès 12 semaines d'aménorrhée (SA) le statut RhD dun foetus à partir d'ADN libre dans le plasma maternel, a été mise au point dans notre laboratoire. Cette technique est appliquée en routine clinique depuis novembre 2002 aux patientes RhD négatif dans le cadre de leur suivi immuno-hématologique. Ce développement ainsi quune première évaluation portant sur 218 grossesses et 223 nouveau-nés ont été rapportés dans un travail original publié dans le J Gynecol Obstet Biol Reprod en 2005 (Minon et al. 2005). La qualité de la prédiction du statut RhD ftal a permis d'envisager l'extension du génotypage à toute patiente RhD négatif. En parallèle, différentes PCR conventionnelles ont été développées pour rechercher les gènes RHD silencieux. Lexistence de variants non fonctionnels du gène RHD - principalement trouvés dans les populations africaine et asiatique - a conduit à amplifier des segments spécifiques du gène RHD fonctionnel (séquences des exons 4 et 5) en plus dune séquence de lexon 10, afin déviter les faux positifs. Toutefois, un résultat faux positif inhabituel, lié en fait à la présence d'un greffon rénal chez l'une de nos patientes, a fait l'objet d'une publication dans Transfusion en 2006 (Minon et al. 2006). La place du génotypage foetal RHD a été réfléchie dans un contexte plus général de prise en charge et de prévention de l'alloimmunisation foeto-maternelle anti-D. Cette réflexion a permis de définir de nouvelles stratégies qui ont été décrites dans la Revue Médicale de Liège en 2006 (Minon et al. 2006). Une synthèse de notre activité tant régionale que nationale entre 2002 et 2006 a été récemment publiée dans Transfusion en 2008 (Minon et al. 2008). Elle reprend l'étude de 563 patientes et de leurs 581 nouveau-nés. Notre expérience dans les grossesses gémellaires y est rapportée. Les pièges (faux positifs et négatifs) de la technique sont abordés et des moyens de prévention pour les éviter sont proposés. Elle a été loccasion dune discussion assez exhaustive sur le génotypage RHD foetal à partir du sang maternel. La faible expression de l'antigène D chez certaines mamans pose un double problème: le premier est lié à la présence d'un gène RHD maternel "intact" qui invalide la recherche du gène RHD foetal dans le plasma. Le second est lié à la confusion induite dans lesprit de l'obstétricien par la présence d'un gène RHD maternel « normal » mais associé à une expression faible de l'antigène D, la patiente étant par ailleurs connue sérologiquement D négative. Sur ce sujet déjà épineux viennent se greffer les particularités des variants D partiels. Une nouvelle stratégie a été définie afin d'orienter l'obstétricien dans le suivi immuno-hématologique et la prophylaxie par anti-D des patientes présentant un D variant (D faible et/ou D partiel). Cette nouvelle approche concerne aussi la politique transfusionnelle à adopter en matière de sang D phéno-compatible. Cette discussion fait partie intégrante de notre sujet et reprendra notre expérience reposant maintenant sur plus de 700 déterminations de RHD ftal réalisées depuis 2007. L'extension du génotypage RHD à toutes les patientes RhD négatif encourage nos équipes à réaliser de manière systématique une prévention par immunoglobulines anti-D à 28 semaines daménorrhée (SA) chez les patientes Rh D négatif dont le foetus est RHD positif. L'introduction de cette prophylaxie modifie le suivi immuno-hématologique obstétrical traditionnel et fait l'objet d'une publication sous presse dans Acta Clinica Belgica (Minon et al. 2008). En corollaire de notre travail, nous avons démontré la fiabilité de la prédiction du sexe foetal par la recherche du gène SRY utilisé comme contrôle interne de la présence de DNA foetal dans le plasma maternel lorsque le foetus est de sexe masculin.