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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
291

Optimalizace sítě transfúzních míst v České republice / Network Optimization of Transfusion Sites in the Czech Republic

Konderlová, Nicolle January 2015 (has links)
This thesis is about medical transfusion sphere, which has nowadays many deficits - as the other spheres in medical industry. Target of this thesis is a proposal of new equipment structure in transfusion service in the Czech Republic, which will be more effective then the existing one and which occurs a reduction of blood processing department. It includes not only calculation of basic expenses needed for installation new system and ensure operations for 5 years and comparison of both variants, but it includes also proposal of centralized managing and changes of staff secure of production process.
292

Bioética e crença religiosa: estudo da relação médico-paciente Testemunha de Jeová com potencial risco de transfusão de sangue / Bioethics and religious belief: a study on the physician-Jehovah\'s Witness patient at potential risk of blood transfusion

Graziela Zlotnik Chehaibar 13 July 2010 (has links)
As Testemunhas de Jeová têm preceitos religiosos que sustentam a recusa da transfusão de sangue e, frequentemente, vivenciam situações nas quais essa recusa pode ser sustentada por aspectos científicos, legais e bioéticos. Este estudo teve como objetivo analisar a relação médico-paciente Testemunha de Jeová, sob a potencial recomendação de transfusão de sangue durante a internação hospitalar. Além disso, também buscou investigar o momento e a forma da identificação do paciente Testemunha de Jeová; analisar a conduta dos médicos frente a um eventual impasse na relação com os pacientes e analisar as escolhas dos pacientes na relação com os médicos; verificar as condutas realizadas após o processo de tomada de decisão entre médico e seu paciente; e verificar se os médicos conhecem o parecer n.º 007/2004 - \"Orientação sobre Recusa de Transfusão de Sangue da Testemunha de Jeová\", da Comissão de Bioética (CoBi) do Hospital das Clínicas da FMUSP. A pesquisa foi realizada no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) no período de fevereiro de 2007 a maio de 2009. Foram selecionados 46 pacientes e 48 médicos, buscando-se entrevistar o paciente e seu respectivo médico. Trata-se de um estudo de caso exploratório, em pesquisa clínica, com abordagem qualitativa e com uso de dados quantitativos. A análise dos dados revelou que 89,6% passaram por cirurgia e 29,2% estiveram em iminente risco de morte. Foram transfundidos 12,5%, e 8,3% chegaram a óbito. Ao se analisar as posturas dos médicos e pacientes entrevistados, quanto à maneira de lidar com a questão das escolhas foi possível identificar cinco categorias de dados, sendo 3 delas para os médicos - deliberador, pragmático e autonomista e 2 para os pacientes Testemunhas de Jeová - liberal e ortodoxo. Os dados revelaram que existe uma busca genuína dos médicos em disponibilizar técnicas alternativas para evitar a transfusão, porém, quando se trata de iminente risco de morte, a decisão é pela transfusão. Observou-se que a identificação dos pacientes como TJ ocorre tardiamente (79,2% somente após a internação) e, em situações de impasse, sempre que envolvido iminente risco de morte, a maioria dos médicos afirmou que optariam pela transfusão, mesmo sem o consentimento do paciente (91,7%). Também foi identificado que há um conhecimento limitado dos médicos sobre as leis e sobre o parecer 007/2004, sendo que 50% dos médicos entrevistados declararam conhecer a comissão de bioética, enquanto e 64,6 % declaram não conhecem o parecer. A maioria dos médicos (72,9%) é favorável a uma conduta padronizada para os pacientes Testemunhas de Jeová. Além disso, outros dados revelaram que pacientes e médicos fazem uso de documentos para salvaguardar suas decisões. Entretanto, na prática, esses documentos se mostram ineficazes, já que não evitam processos contra médicos, nem transfusões em pacientes. Salvar a vida do seu paciente é o principal compromisso da maior parte dos médicos. / Jehovah\"s Witnesses have religious beliefs that support their refusal to blood transfusion which frequently lead them to experience situations in which such refusal may be based on scientific, legal and bioethical principles. The goal of this study is to analyze the relation between physician and Jehovah\"s Witness patient under the potential recommendation of blood transfusion during hospitalization. Besides this goal, the study also sought to investigate the moment and the manner of identifying a Jehovah\"s Witness patient as so; to analyze the physicians\" procedures when facing an impasse in their relation with patients and analyze the patients\" choice in their relation with the physician; analyze the procedures performed after the decision-making process between the physician and his patient; and establish whether physicians know Recommendation No. 007/2004 \"Guidelines about refusal of blood transfusion by Jehovah\'s Witness patients\", from the Bioethics Committee (CoBi) of Hospital das Clínicas da FMUSP. This research was carried out at Clínicas Hospital of University of São Paulo Medical School (HCFMUSP) between February 2007 and May 2009.A total of 46 patients and 48 physicians were interviewed, always trying to interview the patient and his/her respective physician. It is a case-study of exploratory nature in clinical research using a qualitative approach with quantitative data. Data analysis revealed 89.6% of patients underwent surgery and 29.2% were under life threat. A total of 12.5% received blood and 8.3% died. When analyzing physicians`and patient` postures in relation to way they dealt with the issue of choices, five categories were found : three for physicians - deliberator, pragmatic, autonomist - and two for Jehovah\'s Witness patient - liberal and orthodox. The analysis of scientific aspects showed there is a genuine pursuit by the doctors to make alternative techniques available to avoid transfusion, but if there is an imminent risk of death the decision is to use transfusion. Results show the patients identification as JW happens late in the admission process (79.2% only after admission) and, in an impasse, whenever there is an imminent risk of death the majority of the doctors state they would choose to use transfusion even without the patient\'s consent (91.7%). Data also revealed a limited knowledge of doctors about laws and about Recommendation No. 007/2004, with 50% of interviewed doctors affirming they did not know the bioethics committee, and 64.6% did not know the recommendation. Most physicians (72.9%) favor a standard procedure to deal with Jehovah\'s Witnesses patients. Other data show patients and doctors use documents to secure their decisions.However, in practical termos these documents prove to be inefficient as they neither prevent lawsuits against physicians nor transfusions in patients.Saving the patient\'s life is the main commitment for the majority of doctors
293

Vie et mort au creux du berceau de la parentalité gémellaire : devenir d’une survivance du prénatal dans le cas du syndrome transfuseur-transfusé / Life and died in the hollow of the cradle of the twin parenthood : survival of the prenatal in the case of the twin-to- twin transfusion syndrome

Staraci, Stéphanie 22 November 2013 (has links)
L’objectif principal de cette recherche est de comprendre la place de la vie intra utérine dans le cas de la gémellité compliquée d’un syndrome transfuseur-transfusé (STT). Le second objectif concerne la singularité du deuil périnatal d’un jumeau et son devenir pour les parents et pour le jumeau vivant. Une méthodologie a été construite afin de mettre en perspective le vécu de la grossesse à travers le discours des parents (entretien semi-directif de recherche) et le développement psychique de l’enfant à 6 ans, à travers le bilan psychologique (WISC IV, dessin du bonhomme, dessin de la famille et CAT). Le recueil des données s’est fait à partir de 60 familles. Au sein de cette population, une analyse singulière a été faite à partir du matériel recueilli pour 10 enfants du groupe jumeaux et 10 enfants du groupe singletons. Une analyse transversale a été effectuée pour chacun des groupes et pour la totalité de la population. Mes résultats montrent que l’on retrouve chez l’enfant des traces agissantes d’inscriptions traumatiques pré-psychiques. Au WISC IV, les résultats indiquent que 73% des enfants ont un QI total dans la moyenne. Il existe un état de sidération des processus de pensée et un faible investissement dans les apprentissages. Au CAT, on observe des défenses narcissiques liées à une difficulté de l’élaboration de la position dépressive ainsi qu’une inhibition importante. La confusion et l’indifférenciation des espaces psychiques sont présentes. Dans le dessin de la famille et le CAT, les processus d’identifications se retrouvent d’un jumeau vers l’autre-jumeau, aboutissant à des limites du moi aux contours mal définis. Les identifications aux imagos parentales apparaissent comme secondaires. Cette recherche a montré que la présence du STT contient une potentialité traumatique dans les chaines générationnelles parents/enfants qui s’organise en trois temps. La relation d’objet gémellaire a été décrite comme « le nid prénatal » des relations objectales ultérieures, formées par le trio et le quartet. Ce type de relation inaugure une triadification primaire. Le complexe gémellaire a été décrit selon trois versants : archaïque, oedipianisé et selon l’effet du couple dans la gémellité. Pour les parents qui ont perdu un jumeau durant la grossesse, la perte d’un fœtus jumeau peut devenir un objet de survivance, liée au fonctionnement psychique des parents et au statut du fœtus-jumeau. Chez l’enfant, la place qu’occupe le jumeau décédé pour le vivant est fonction de l’élaboration du deuil des parents. La perte du jumeau peut devenir un objet de survivance, compte tenu de la nature narcissique et pré objectale de la gémellité. Le syndrome du survivant peut se retrouver chez l’enfant. / This thesis explores the phenomenon of twins who develop Twin to twin Transfusion Syndrome (TTTS), and the subsequent metaphyschological effects on both the perinatal and future development of children. The objective of this research is to understand intrauterine life using the context of afterward. Therefore, this research is focused on the link between parents’ experiences of afterward during their pregnancy, and the physical development of 6 year old twins. The second objective of this research concerns the perinatal death of one twin and how life develops in the future for the parents and for the living twin. The methods used are the psychoanalytic and the test method, in a psychodynamic approach. The tools used are the semi-direct research interview and the psychological evaluation of the child. (WISC IV, the drawing of man, the drawing of family and the projective test of the CAT). The collection of data is conducted with more than 60 families who have 6 year old children. At the heart of the population, a single analysis was made from material received for 10 children from a group of twins and 10 single children. A cross sectional analysis was done for each group and for the total of the population. My results show that we can find traces of registered pre-psychic trauma. From the WISC IV test, the results indicate that 73% of children have an average IQ. There is a state of paralysis in thought processes, and little interest in learning. The CAT showed narcissistic defenses related to difficulty in developing the depressive position, as well as significant inhibition. Confusion and lack of differentiation of psychic spaces are present. In the drawing of the family and in the CAT, the identification of one twin with the other twin can be found, resulting in poorly defined boundaries of self. Identification with parental images appears to be secondary. The presence of TTTS has the potential to cause trauma through the generational chain of parent/ child that is organised in three stages. Twin object relations have been described as “the prenatal nest” of subsequent object relations, formed by the trio and the quartet. This type of relationship introduces a primary triadification. Three aspects of the twin complex have been described: archaic, oedipianized and according to the effect of the couple in the twinning. For those parents who have lost a twin during pregnancy, the loss of a twin foetus can become an object of survival, or an object of trauma, linked to the psychic functioning of the parents and the status of the twin foetus. The place the living twin takes, in place of the dead twin, is dependent on the grieving process of the parents. Based on this, the loss of a twin can become an object of survival, taking into account the narcissistic and pre objectal nature of the twinning. Survival Syndrome can be found in children.
294

Problematika dárcovství krve z pohledu lékařů a laické veřejnosti / The issue of blood donation from the perspective of doctors and the general public

Cicák, Filip January 2021 (has links)
Introduction: The properties of human blood are so specific that it has not yet been possible to replace human blood with any other fluid than obtaining it as a blood gift from donors. In recent years, there has not been a sufficient number of new blood donors in the Czech Republic to compensate for the decrease in the number of donors due to the increasing incidence of a number of civilization diseases and age (Czech Red Cross, 2020). Blood donation and the need for blood products are constantly increasing with the development of the methods of treatment and medicine as a science. Ensuring a sufficient number of blood donors and sufficient deposition of blood obtained from donors is a permanent task of healthcare (Society for Transfusion Medicine of the Czech Medical Association JEP, 2019). Aim of the work: The main goal of the research was to map the issue of blood donation, to identify the factors by which blood donors are motivated to donate. Furthermore, what can cause stagnation in the growth of blood donors and what means doctors motivate potential blood donors. Methodology: A qualitative research method was chosen for the research survey. Data collection took place in the form of semi-structured interviews and was completed by achieving theoretical data saturation. In order to preserve...
295

Avancées en médecine transfusionnelle féline : de l’optimisation du prélèvement à la découverte de nouveaux antigènes érythrocytaires

Binvel, Marie 07 1900 (has links)
La médecine transfusionnelle féline a connu une croissance exponentielle au cours des dix dernières années. La découverte du système de groupes sanguins AB et la meilleure compréhension des mécanismes d’incompatibilité donneur-receveur, ainsi que le développement de systèmes de collecte adaptés au chat et de techniques de typage sanguin au chevet du patient ont permis d’améliorer la sécurité des transfusions. Notre travail s’est intégré dans cette volonté d’optimiser la sécurité des transfusions sanguines chez le chat en se concentrant sur deux aspects différents : le prélèvement de sang et les antigènes érythrocytaires à l’origine d’incompatibilités donneur-receveur non expliquées par le système AB. Dans un premier temps, un système de collecte de sang adapté au chat a été fabriqué afin de permettre un prélèvement fermé et autoriser le stockage des produits sanguins. Ce système a été comparé à un système ouvert composé de seringues. Le système fermé apparaît adapté au prélèvement de sang car aucune différence significative n’a été enregistrée dans les paramètres vitaux des donneurs après le prélèvement, le succès du prélèvement, ou la qualité du produit sanguin en termes de contamination bactérienne et d’hémolyse, entre les deux systèmes. Le net avantage du système fermé est qu’il assure un temps de prélèvement plus rapide que le système ouvert. Dans un second temps, en réalisant des tests de compatibilité chez 258 chats de type A, nous avons montré que la probabilité de détecter des incompatibilités entre deux chats de groupe A sélectionnés aléatoirement était de 3.9 %, et que 7 % des chats de groupe A présentaient des allo-anticorps naturels extérieurs au système AB. Sept des 18 allo-anticorps naturels détectés ont été utilisés comme réactifs lors d’un typage sanguin extensif. Les analyses sur l’accord des résultats du typage obtenus avec les différents réactifs ont permis d’identifier cinq nouveaux antigènes érythrocytaires félins différents, nommés FEA 1 à FEA 5 (pour feline erythrocyte antigen), dont l’hérédité, la prévalence, la distribution géographique et par race, ainsi que l’immunogénicité restent encore à déterminer. / Feline transfusion medicine has grown exponentially over the past decade. The discovery of the AB blood group system and the better understanding of the mechanisms of donor-receiver incompatibility, as well as the development of cat-friendly collection systems and bedside blood typing techniques have improved transfusion safety. Our work has been part of this effort to optimize the safety of blood transfusions in cats by focusing on two different aspects: blood collection and red blood cell antigens that cause donor-recipient incompatibilities unexplained by the AB system. First, a blood collection system adapted to the cat was manufactured to allow collection in a closed-system and storage of blood products. This system was compared to an open system consisting of syringes. The closed system appeared well-adapted for feline blood collection because no significant difference was found in the vital parameters of the donors after collection, the success of the collection, or the quality of the blood product in terms of bacterial contamination and hemolysis. The distinct advantage of the closed system was that it provided a shorter duration of collection than the open system. Secondly, based on the systematic crossmatches of 258 cats, we showed that the probability of detecting incompatibilities by randomly crossmatching two type A cats was 3.9 %, which resulted in at least 7 % of type A cats having naturally occurring alloantibodies outside the AB blood group system. Seven of the 18 detected naturally occurring alloantibodies were used as reagents in an extensive blood typing. Comparison of the results obtained from this extensive blood typing supports the existence of five, presumably different, new feline erythrocyte antigens, named FEA 1 to FEA 5, whose mode of inheritance, geographical and breed distribution, frequency and immunogenicity have yet to be determined.
296

Transfusions de globules rouges en néonatologie et syndrome de défaillance multiviscérale aiguë

Villeneuve, Andréanne 04 1900 (has links)
Le niveau d’hémoglobine (Hb) d’un nouveau-né diminue dans les premiers mois de vie. Cette anémie dite physiologique est plus sévère chez les nourrissons admis aux soins intensifs néonataux (SIN), et ceux-ci nécessitent souvent une transfusion sanguine. En néonatalogie, les indications de transfuser sont controversées et les pratiques transfusionnelles sont très variables. Pour mieux comprendre ces pratiques, nous avons mené l’étude prospective «Epidemiology and determinants of red blood cells transfusion in a neonatal intensive care unit: a cohort study». 13.4% des patients consécutifs admis aux SIN pendant l’étude ont reçu au moins une transfusion sanguine. Les prématurés nés à moins de 28 semaines d’âge gestationnel ont reçu la majorité des transfusions (62.2%) mais les nourrissons à terme admis aux SIN sont aussi fréquemment transfusés (4.9% des transfusions). Les principales justifications évoquées par les cliniciens prescrivant des transfusions sont un niveau bas d’Hb, la maladie de base et le désir d’améliorer l’oxygénation des organes. Notre étude a confirmé une grande variabilité du seuil d’Hb justifiant une transfusion, s’étendant de 62 à 137 g/L. Le syndrome de défaillance multiviscérale (SDMV), défini par l’observation simultanée d’au moins deux dysfonctions d’organes, est un facteur important de mortalité-morbidité chez les enfants traités en soins intensifs pédiatriques. L’association entre SDMV et transfusions est bien décrite dans cette population. Deux listes de critères diagnostiques du SDMV pédiatrique sont utilisées dans la littérature médicale : celles de Proulx et de Goldstein. Nous avons entrepris l’étude de cohorte prospective «Multiple organ dysfunction syndrome in critically ill children : clinical value of two lists of diagnostic criteria» dans le but de valider et de comparer leur valeur diagnostique respective. Nos résultats ont démontré que l’épidémiologie du SDMV varie selon la définition utilisée : l’incidence était de 21.4% vs. 37.3% selon les critères de Proulx et de Goldstein respectivement. Les deux listes de critères diagnostiques ont une bonne reproductibilité inter- et intra-observateur; celle de Proulx est cependant associée à une plus haute mortalité à 90 jours (17.8% vs. 11.5%, p = 0.038). Le SDMV a été décrit chez les nouveau-nés en SIN en utilisant le NEOMOD, un score adapté à cette population. Avec une meilleure caractérisation, le SDMV deviendrait un critère de jugement intéressant pour les essais cliniques randomisés en médecine transfusionnelle en néonatologie. / In the first few months of life, the level of hemoglobin (Hb) in the newborn normally decreases. This physiological anemia is more severe in neonates admitted to a neonatal intensive care unit (NICU), who frequently require a red blood cells (RBC) transfusion. In neonatal medicine, the indications for transfusion are controversial and practices are highly variable. To better understand those practices, we conducted the prospective study: «Epidemiology and determinants of red blood cells transfusion in a neonatal intensive care unit: a cohort study». Among the patients consecutively admitted to NICU during the study period, 13.4% received at least one RBC transfusion. Although premature babies born at less than 28 weeks gestation received the majority of transfusions (62.2%), term neonates admitted to NICU were also frequently transfused (4.9% of transfusions). The main justifications for giving a RBC transfusion were: low Hb level, underlying illness and to improve oxygen delivery. We also observed a wide range of Hb thresholds that triggered a decision to transfuse (from 62 to 137 g/L). The multiple organ dysfunction syndrome (MODS), which is defined as the simultaneous dysfunction of at least two organs or systems, is highly associated with mortality and morbidity in critically ill children. The association between MODS and transfusions is also well described in this population. Two sets of criteria of pediatric MODS are currently used in the medical literature: one by Proulx, and another by Goldstein. We did the prospective cohort study «Multiple organ dysfunction syndrome in critically ill children : clinical value of two lists of diagnostic criteria» to validate and compare the diagnostic value of those two definitions of MODS. We observed that the epidemiology of MODS varies according to which list of criteria is used: the incidence was 21.4% vs. 37.3% with Proulx and Goldstein criteria, respectively. Both sets of criteria have a good inter- and intra-rater reproducibility. The diagnostic of MODS according to Proulx criteria is associated with higher 90-days mortality (17.8% vs. 11.5%, p = 0.038). MODS is also described in neonates, using a score adapted to this population, the NEOMOD. Neonatal MODS represents an interesting outcome measure in clinical trials in neonatal transfusion medicine. However, prior to that, it needs to be better characterized.
297

Régulations homéostatiques cardiovasculaires suite à une transfusion par échange avec du sang hyperagrégeant chez le rat

Vanier, Julie 12 1900 (has links)
Dans le but de vérifier l’impact d’un changement soudain dans l’agrégation érythrocytaire sur certains paramètres cardiovasculaires, une transfusion par échange sanguin du tiers du volume a été effectuée avec du sang hyperagrégeant chez le rat de souche Brown Norway. La pression caudale, le volume cardiaque systolique, la fraction d’éjection, le débit cardiaque, le rythme cardiaque et la résistance périphérique à l’écoulement sanguin ont été observés non-intrusivement sur 19 jours suite à la transfusion. Les rats ont été sacrifiés plus d’un mois suivant la transfusion et une étude ex vivo de la réponse à deux agents dilatateurs (l’acétylcholine et le nitroprussiate de sodium) a été menée sur les artérioles mésentériques. Des variations des paramètres cardiovasculaires, soit le débit, le volume systolique et la résistance périphérique, ont été remarquées dans les trois premiers jours posttransfusion. Une résistance du muscle vasculaire lisse au monoxyde d’azote a été notée chez les rats transfusés au sang hyperagrégeant alors qu’aucune dysfonction endothéliale n’était apparente en réponse à l’acétylcholine. / The aim of this study was to evaluate the effects of an acute change in erythrocyte aggregation on cardiovascular parameters by exchanging one third of the blood volume with hyperaggregating blood in the Brown Norway rat model. Values of caudal pressure, systolic cardiac volume, ejection fraction, cardiac output, heart rate and peripheral resistance to blood flow were observed non-invasively over 19 days after transfusion. The rats were sacrificed after more than a month following the procedure and an ex vivo study in response to pharmacological agents (acetylcholine and sodium nitroprussiate) was performed on mesenteric arterioles. Variations in cardiac output, systolic volume and peripheral resistance were noted for the first three days post-transfusion. The vascular smooth muscles of rats transfused with the hyperaggregating erythrocytes seemed to have developed a resistance to nitric oxide but no endothelial dysfunction was observed in response to acetylcholine.
298

Neogênese de células T e B em pacientes com doença falciforme tratados com diferentes modalidades terapêuticas / Neogenesis of T and B cells in patients with sickle cell disease treated with different therapeutic modalities

Jarduli, Luciana Ribeiro 06 April 2018 (has links)
As doenças falciformes (DF) constituem um grupo de doenças hereditárias monogênicas. São doenças extremamente relevantes no contexto de saúde pública no Brasil, portanto diferentes estratégias terapêuticas devem ser avaliadas. As oclusões vasculares afetam praticamente todos os órgãos, inclusive o baço e a medula óssea, porém não existem dados na literatura se estas comprometem também o tecido tímico. Os pacientes apresentam maior suscetibilidade às infecções cujas causas não são ainda totalmente esclarecidas Embora as infecções observadas nos pacientes sejam atribuídas à disfunção esplênica, o quadro inflamatório crônico e possíveis alterações no timo e na medula óssea, também poderiam causar uma disfunção imunológica. O objetivo deste trabalho foi avaliar a neogênese de células T e B e a diversidade do repertório de células T periféricas em pacientes com anemia falciforme (AF) sem tratamento (N = 15), tratados com hidroxiuréia (N = 20) ou transfusão crônica (N = 21) e em pacientes com DF tratados com transplante de células-tronco hematopoéticas (TCTH) alogênico (N = 29). Pacientes sem tratamento apresentaram menores níveis de sjTREC e ?-TREC, e menor taxa de divisão celular intratímica, demonstrando alterações importantes na neogênese das células T. A produção tímica de novas células T naïve foi reestabelecida em um ano pós-transplante, com normalização dos níveis de sjTREC e ?-TREC. O desenvolvimento de doença do enxerto contra o hospedeiro (DECHa) e reativação de citomegalovírus comprometeu a timopoiese nos primeiros seis meses pós-transplante, com diminuição significativa dos níveis de sjTRECs e ?-TRECs. Análises do repertório da cadeia V? dos receptores de células T (TCRs), pelo método TCRBV CDR3 spectratyping, indicaram que os pacientes com AF apresentaram um repertório menos diverso, composto predominantemente de famílias V? com padrão skewed e picos de CDR3 monoclonais, sendo a família V?3 mais frequente. A composição do repertório de células T foi alterada após o transplante, adquirindo um perfil mais policlonal dos picos de CDR3 ao longo do tempo. A família V?22 foi a mais expressa no período pré-transplante e em todos os seguimentos pós-transplante. Os pacientes com DF apresentaram aumento de linfócitos B naive, demonstrado pelos altos níveis de sjKRECs e pela taxa de proliferação homeostática. As análises multivariadas demonstraram que as alterações esplênicas influenciam diretamente os níveis de sjKREC, indicando que a baixa função esplênica leva ao aumento da produção de células B naive pela medula óssea, sugerindo um mecanismo compensatório. Os resultados desse trabalho demonstraram a existência de um desequilíbrio na neogênese de células T e B e consequentemente nesses compartimentos celulares periféricos, que pode conferir aos pacientes com DF uma maior susceptibilidade a infecções. Entre as diferentes modalidades terapêuticas, o TCTH alogênico sobressaiu-se em relação aos tratamentos convencionais, melhorando a neogênese de células T e B a longo prazo. / Sickle Cell Disease (SCD) are a group of monogenic hereditary diseases. These are extremely relevant diseases in the context of public health in Brazil, thus, different therapeutic strategies must be studied. Vascular occlusions affect practically all organs, including the spleen and bone marrow. However, there are no literature data about the impact of vaso-occlusions on the thymic tissue. Patients are more susceptible to infections whose causes are not fully elucidated. Although the infections observed in these patients are assigned to splenic dysfunction, the chronic inflammatory state and possible alterations of the thymus and bone marrow could also lead to immune dysfunction. The goal of this work was to evaluate the neogenesis of T and B cells and the diversity of peripheral T cell repertoire in patients with sickle cell anemia (SCA) without treatment (N = 15), treated with hydroxyurea (N = 20) or chronic transfusions (N = 21) and in patients with SCD treated with hematopoietic stem cell transplantation (N = 29) allogeneic. Patients without treatment had lower levels of sjTREC and ?-TREC, and lower rate of intrathymic cell division, demonstrating important alterations in the neogenesis of T cells. The thymic production of new naïve T cells was reestablished at one-year post transplantation, with normalization of sjTREC and ?-TREC levels. The development of graft-versus-host disease (aGVHD) and cytomegalovirus activation compromised thymopoiesis in the first six months post transplantation, with a significant decrease of sjTRECs and ?-TRECs levels. Analysis of the TCR V? chain repertoire by TCRBV CDR3 spectratyping indicate that patients with SCA showed a less diverse repertoire, mainly composed by V? families with a skewed pattern and monoclonal CDR3 peaks, being the V?3 family the most frequent one. The composition of the T-cell repertoire was altered after transplantation, changing over time to more polyclonal profile of the CDR3 peaks. The V?22 family was the more expressed at pre-transplantation and at all follow-up periods. Patients with SCD presented increased numbers of naive B cells, demonstrated by higher levels of sjKRECs and homeostatic proliferation. Multivariate analysis demonstrated that splenic function directly influenced sjKREC levels, indicating that compromised splenic function leads to increase of naive B cell output by the bone marrow, suggesting a compensatory mechanism. The results of this study showed the existence of an imbalanced T and B cell neogenesis and, consequently on these peripheral cell compartments, which may confer to patients with SCD an increased susceptibility to infections. Among different therapeutic modalities, allogeneic HSCT stood out in relation to the conventional treatments, improving long-term T and B cell neogenesis.
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"Prevalência do HHV - 8 em doadores de sangue e politransfundidos na cidade de São Paulo, pelas técnicas de imunofluorescência indireta e Nested PCR" / Prevalence of HHV-8 in blood donors and recipients in the city of São Paulo, by indirect imunofluorescent assay and Nested PCR

Ferreira, Suzete Cleusa 18 August 2005 (has links)
A prevalência de anticorpos e DNA viral de HHV-8 em 400 doadores de sangue e 50 indivíduos politransfundidos da Fundação Pró-Sangue Hemocentro de São Paulo, através das técnicas de Nested PCR e IFI para antígenos lítico e latente. Foi detectada uma soroprevalência mais alta entre doadores de sangue(4%) quando comparados a indivíduos politransfundidos (14%) (p= 0,002). A prevalência também foi mais alta entre mulheres em relação a homens, 7% versus 1.8% (p= 0,012; 95% IC 1,14 - 16,6). Foram detectados DNA de HHV-8 no plasma e PBMC de um doador 0.25%. Esta amostra foi seqüenciada confirmando a presença de HHV-8. O encontro de DNA viral no plasma de um doador de sangue indica a transfusão sanguínea como um possível meio de transmissão deste agente / The prevalence of antibodies and DNA viral of HHV-8 in 400 donors of blood and 50 receiving of the Fundação Pró-Sangue Hemocentro of São Paulo, through Nested PCR'S techniques and IFI for lithic and latent antigens. A seroprevalence of 4% was detected in the donors of blood and 14% in receiving, significantly high in comparison with the prevalence in donors of blood (p = 0,002). There was a significant difference in the prevalence among men 1,8% and 7% in the women (p= 0,012; 95% CI 1,14 - 16,6). They were detected DNA of HHV-8 in the plasma and a donor's 6,3% PBMC, and it was sequenced and submitted to the Gene Bank where presented 100% of identity. This allows to define the transmission tax and the need of introducing methods for this agent's selection
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Doadores de granulócitos, plaquetas e sangue total. O real perfil altruístico e seu capital social / Granulocyte donors, platelets and whole blood donors: the real altruistic profile and their social capital

Rocha, Pedro Capuani 29 May 2013 (has links)
O concentrado de granulócitos é um importante componente para o tratamento de pacientes oncológicos. A doação deste componente é mais complexa do que outras doações de sangue ou hemocomponentes, porque necessita de maiores esforços e assumção de riscos por parte do doador e, também, o uso de equipamento automatizado de aférese. O presente estudo tem o objetivo de aumentar o conhecimento sobre a população de doadores de granulócitos e avaliar a diferença entre suas motivações para realizarem as doações e seu capital social geral comparando com doadores de plaquetas e doadores altruistas de sangue total. Com esses resultados os hemocentros que realizam a coleta de granulócitos não só poderão ter informações mais objetivas que tornem mais eficaz o recrutamento deste tipo de doador e, consequentemente, aumentar a disponibilidade deste componente como também, identificando um perfil semelhante dos doadores de granulócitos na população geral de doadores o banco de sangue poderá fidelizar estes indivíduos e promover doações de sangue mais seguras. O perfil dos doadores de granulócitos foi avaliado a partir de um estudo caso-controle, sendo o grupo casos formado por estes doadores (n=64) e, os controles por doadores de plaquetas (n-64) e de sangue total (n=68), na razão de um caso para dois controles. Doadores de granulócitos são principalmente do sexo masculino e com idade mais avançada do que os controles. Com referência às motivações para doarem, doadores de granulócitos não se diferem substancialmente dos doadores de plaquetas, mas em relação aos doadores de primeira vez de sangue total há diferenças consideráveis principalmente no que diz respeito ao interesse nos resultados dos testes sorológicos. Doadores de sangue total são quase duas vezes mais motivados a doarem pelo recebimento dos resultados comparados aos doadores de granulócitos, bem como também se motivam mais a doarem para tirar o dia de folga do trabalho o que indica um gesto de menor altruísmo destes daodores. O perfil sócio determinante entre os grupos de doadores também se difere, doadores de granulócitos são pessoas efetivamente mais engajadas socialmente comparados aos controles e têm de uma rede comunitária mais coesa e confiável, concordando cerca de duas vezes mais do que doadores de plaquetas que têm vizinhos conhecidos que os ajudaria financeiramente (OR=2,49) ou concordando quatro vezes mais que doadores de sangue total que têm vizinhos conhecidos que estariam sempre prontos a ajudar outros vizinhos (OR=4,02). Concluimos que os resultados indicam que há a necessidade dos bancos de sangue utilizarem novas estratégias de recrutamento para aumentar a conversão de doadores, passando a utilizar, além do recrutamento interno, comunicações mais efetivas que, consigam atingir a população foco com maior eficiência, em locais onde a probabilidade de encontrar doadores mais engajados socialmente é aumentada, como clubes, centros comunitários ou associações / The concentrate of granulocytes is an important component for oncologic patient\'s treatment. Donation of this component is more complex than other blood components donations, because it claims more efforts and risks assumptions by the donor, and also the use of automated apheresis equipment. The present study is aimed to increase knowledge about the granulocyte donors´ population and evaluate differences among their motivations to accomplish donations and their general social capital, comparing with platelets apheresis donors and altruistic whole blood donors. These results may help blood centers, which carry granulocyte collection, not just to achieve much more objective information about these donors, but also to identify similar granulocyte donors´ profile within the general population. Blood banks may be able to achieve fidelity among these individuals and to promote safer blood donations. Granulocyte donors´ profile was evaluated in a case-control study. Cases were formed by granulocytes donors (n=64) and controls by platelet apheresis donors (n-64) and first time whole blood donors (n=68), in a ratio of one case per two controls. Granulocyte donors are mainly male and older than controls. Regarding the motivation to donate, granulocyte donors are not essentially different from platelets donors, but regarding first time whole blood donors, there are considerable differences, especially in respect to test seeking. Moreover, whole blood donors are almost twice more motivated to donate to take a day off at work, which shows a minor altruistic gesture. The determinant social profile among donors´ groups is also different. Granulocyte donors are effectively more social engaged people when compared to controls, and have a much more coherent and trustful community net, assenting about twice more than platelets donors, which have acquainted neighbors that would be ever ready to help other neighbors (OR=4.02). In conclusion, these findings indicate that is necessary to blood centers to use new recruitment strategies to increase donor´s retention. More effective communications procedures, besides internal recruitment, that achieves the target with more efficiency in locals where the probability to find donors more social engaged is increased, as clubs, community centers or associations must be warranted

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