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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.
231

Estudo prospectivo de infecção por calicivírus (norovírus e sapovírus) em pacientes submetidos a transplante alogênico de células progenitoras hematopoiéticas / Prospective study of calicivirus infection (norovirus and sapovirus) in patients undergoing allogeneic hematopoietic stem cell transplantation

Lemes, Lucianna Gonçalves Nepomuceno 20 December 2013 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-09-25T17:34:38Z No. of bitstreams: 2 Dissertação_Lucianna G. N. Lemes.pdf: 2661301 bytes, checksum: c0238e41dfbe2adbd10e5ddcff7a139e (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-26T11:31:18Z (GMT) No. of bitstreams: 2 Dissertação_Lucianna G. N. Lemes.pdf: 2661301 bytes, checksum: c0238e41dfbe2adbd10e5ddcff7a139e (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-26T11:31:18Z (GMT). No. of bitstreams: 2 Dissertação_Lucianna G. N. Lemes.pdf: 2661301 bytes, checksum: c0238e41dfbe2adbd10e5ddcff7a139e (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-12-20 / The calicivirus (norovirus and sapovirus) are important etiologic agents of acute gastroenteritis. Recent studies show that in immunocompromised patients such as those undergoing allogeneic hematopoietic stem cell transplantation (HSCT), norovirus infection can lead to worsening of symptoms and be confused with clinical symptoms of graft versus host disease (GVHD). However, calicivirus screening is not performed, routinely, as part of the patients’ follow-up laboratory exams. The main objective of this study was to evaluate the occurrence of norovirus (NoV) and sapovirus (SaV) in patients who underwent HSCT, and to conduct the molecular characterization of the samples positive for these viruses. Fecal samples were collected weekly, and serum samples were obtained every two weeks of ten patients who underwent HSCT, for a minimum period of five months and a maximum of one year. The secretor status was determined by an enzyme immunoassay and the detection of calicivirus was performed by RT-PCR using primers specific for a partial region of the gene encoding the NoV genogroup I and II (GI and GII) and SaV capsid protein. The genomic sequencing was performed for positive samples. The results showed that from ten patients participating in the study, eight had diarrhea. Among these, six (60%) had positive samples for NoV, and all of them had a secretor phenotype. The duration of NoV excretion in feces ranged from five to 143 days. Viral RNA was also detected in serum specimens, ranging from 29 to 36 days in the five patients infected with NoV. Three of the six patients had acute intestinal GVHD. Through genomic sequencing and phylogenetic analysis all NoV-positive samples were characterized as genotype GI.3, and because they had a high nucleotide identity, they were all characterized as a single haplotype. The data highlight the urgent need of the inclusion of calicivirus screening in the routine testing performed before transplantation and during follow-up of these patients. This is the first report of the occurrence of NoV in patients undergoing HSCT in Brazil. / Os calicivírus (norovírus e sapovírus) são importantes agentes etiológicos da gastroenterite aguda. Estudos recentes mostram que em pacientes imunocomprometidos, como os submetidos a transplante alogênico de células progenitoras hematopoiéticas (TACPH), a infecção por norovírus pode levar ao agravamento dos sintomas e ser confundida com quadro clínico da doença do enxerto contra o hospedeiro (DECH). Entretanto, a triagem para calicivírus não é realizada, rotineiramente, como parte dos exames laboratoriais de acompanhamento destes pacientes. O principal objetivo deste estudo foi avaliar a ocorrência de norovírus (NoV) e sapovírus (SaV) em pacientes que foram submetidos ao TACPH e proceder à caracterização molecular das amostras positivas para estes vírus. Foram obtidas amostras de fezes, coletadas semanalmente, e de soro, a cada quinze dias, de dez pacientes que realizaram o TACPH, por um período mínimo de cinco meses e máximo de um ano. O fenótipo secretor dos pacientes foi determinado utilizando um teste imunoenzimático e a pesquisa de calicivírus foi realizada pela RT-PCR, utilizando-se iniciadores específicos para uma região parcial do gene codificante para a proteína dos capsídeos dos NoV do genogrupo I e II (GI e GII) e dos SaV. Os amplicons das amostras positivas foram submetidos ao sequenciamento genômico e análise filogenética. Os resultados obtidos revelaram que de dez pacientes participantes do estudo, oito apresentaram diarreia e vômito. Dentre esses, seis (60%) apresentaram amostras positivas para NoV, sendo que todos foram identificados como secretores. O período de excreção de NoV nas fezes variou de cinco a 143 dias. Foi também detectado RNA viral nas amostras de soro, variando de 29 a 36 dias, em cinco pacientes infectados por NoV. Três, dos seis pacientes, apresentaram DECH aguda intestinal. Através do sequenciamento genômico e análise filogenética, todas as amostras positivas para NoV, de todos os pacientes, foram caracterizadas como genótipo GI.3 dos NoV, e como foi comprovada elevada identidade nucleotídica entre elas, foram caracterizadas como um único haplótipo. Os dados obtidos ressaltam a urgente necessidade da inclusão da pesquisa de calicivírus na rotina de exames realizados antes do transplante, bem como durante o acompanhamento destes pacientes. Este é o primeiro relato da ocorrência de NoV em pacientes submetidos ao TACPH no Brasil.
232

Modulação do microambiente periférico pelas células-tronco mesenquimais e meio condicionado na fibrose pulmonar experimental / Modulation of the peripheral microenvironment by mesenchymal stem cells and conditioned medium in experimental lung fibrosis

Renato Gonçalves Felix 29 May 2018 (has links)
Introdução: A fibrose pulmonar idiopática (FPI) é definida como um tipo de doença fibrosante intersticial crônica de etiologia desconhecida limitada aos pulmões e que apresenta padrão histológico de pneumonia intersticial usual. A prevalência de FPI é estimada em, aproximadamente, 20/100.000 em homens e em 13/100.000 em mulheres, sendo que a idade média do diagnóstico é 67 anos e a sobrevivência média é 2 a 5 anos. Estima-se que 5 milhões de pessoas sejam afetadas em todo o mundo. O tratamento clínico atual está associado com melhora parcial e transitória, com resultados duvidosos ou insatisfatórios. Na abordagem cirúrgica da FPI, tem destaque o transplante pulmonar, cuja realização é rara, devido à escassez de doadores e à limitação das equipes capazes de realizar tais procedimentos. A terapia celular é uma alternativa terapêutica com grande potencial de aplicabilidade na fibrose pulmonar. Objetivos: Utilizar um modelo de fibrose pulmonar induzida pela bleomicina em ratos para investigar os efeitos da terapia com células-tronco mesenquimais (CTM) e o meio condicionado no remodelamento pulmonar com objetivo de elucidar o mecanismo de ação das CTM e meio condicionado, na reversão da fibrose pulmonar. Para tanto, buscamos: 1) padronizar a cultura de células-tronco mesenquimais e meio de cultura; 2) caracterizar o modelo experimental de fibrose pulmonar induzida pela bleomicina por microscopia óptica antes e após o tratamento com CTM e meio de cultura; 3) avaliar a expressão de biomarcadores sorológicos (Fibrinogênio, Fator von Willebrand e PDGF); 4) quantificar a expressão de proteínas relacionadas ao estresse oxidativo (NOS), citocinas pró-inflamatórias e pró-fibróticas (IL-17 e TGF-beta) e pró-angiogênicas (VEGF e endotelina) por imuno-histoquímica; e 5) quantificar a deposição de fibras do colágeno I e V por imunofluorescência. Materiais e Métodos: Utilizou-se um total de 44 ratos Wistar machos albinos com peso médio de 250-300g e 8 semanas de idade. Quatro grupos experimentais foram compostos de 10 animais, que participaram do experimento divididos em três momentos: D0, D10 e eutanásia (D14 ou D21). Em D0, foi realizada a instilação orotraqueal de bleomicina na dose de 1,5 U/kg; em D10, foi realizada a infusão em veia caudal de células-tronco mesenquimais na dose de 106 CTM/Kg ou 200 ?l de meio condicionado. Para o preparo das CTM, foi obtido, em média, 1,2 g de tecido adiposo, procedida a dissociação com colagenase tipo I, sendo que a contagem média de células foi de 3,05 x 106 células linfomononucleares/g de tecido adiposo. Estas células foram cultivadas durante 21 dias em meio Knockout DMEM-F12 suplementado com 10% de soro fetal bovino. Os seguintes três critérios foram utilizados para comprovar o perfil das células-tronco mesenquimais: aderência plástica, expressão de CD90 por citometria de fluxo ( > 90%) e capacidade de diferenciação em três linhagens mesodérmicas. Em D10, um pool destas células alogênicas foi infundido intravenosamente, na veia caudal, a uma concentração de 1 x 106 células/ animal num volume de 200 ul de solução salina. Em D14 ou D21, os animais foram eutanasiados e analisados quanto ao peso e conforme análises microscópico-laboratoriais. As análises histológicas foram realizadas por dois especialistas diferentes em estudo duplo-cego. Os parâmetros de ganho de peso e recuperação microscópica do tecido pulmonar foram analisados em cada grupo. Resultados: Nossos dados mostram que as células-tronco mesenquimais oriundas do tecido adiposo abdominal de ratos Wistar tiveram seu perfil fenotípico, capacidade de adesão plástica e diferenciação em 3 linhagens mesodérmicas estabelecidas inequivocamente, conforme estabelecido internacionalmente pela ISSCR. As células-tronco mesenquimais e o meio condicionado induziram: a recuperação clínica após tratamento; a reversão da inflamação e de fibrose pulmonar induzida pela bleomicina; a reversão da arteriopatia no parênquima pulmonar distal; a redução das concentrações de fibrinogênio, fator von Willebrand e PDGF (marcadores sorológicos); a diminuição da expressão de enzimas oxidantes; a diminuição da expressão de endotelina e a modulação da expressão da proteína de remodelamento (IL-17), da ativação dos fibroblastos TGF-B e da síntese de colágeno. Conclusão: Neste estudo, comprovamos que as terapias com células-tronco mesenquimais derivadas do tecido adiposo e com o meio condicionado foram eficazes na modulação dos processos inflamatórios e fibrogênicos no modelo induzido por bleomicina, agindo na ativação miofibroblástica, e, também, na restauração tecidual e endotelial. Além disso, o meio condicionado se mostrou tão eficiente quanto as células-tronco propriamente ditas, no efetivo remodelamento pulmonar, devendo ser considerado como uma proposta terapêutica viável e inovadora / Introduction: Idiopathic pulmonary fibrosis (IPF) is defined as a type of chronic interstitial fibrosing disease of unknown etiology limited to the lungs and presenting a histological pattern of usual interstitial pneumonia. The prevalence of IPF is estimated at approximately 20/100,000 in men and 13/100,000 in women, with the mean age of diagnosis being 67 years and the average survival is 2 to 5 years. It is estimated that 5 million people are affected worldwide. The current clinical treatment is associated with partial and transient improvement, with dubious or unsatisfactory results. In the surgical approach to IPF, pulmonary transplantation is a prominent feature, which is rare because of the scarcity of donors and the limitation of the teams capable of performing such procedures. Cell therapy is a therapeutic alternative with great potential for applicability in pulmonary fibrosis. Objectives: To use a model of bleomycin-induced lung fibrosis in rats to investigate the effects of mesenchymal stem cell (MSC) therapy and conditioned medium on lung remodeling in order to elucidate the mechanism of action of MSC and conditioned medium, in the reversion of pulmonary fibrosis. To do so, we aim to: 1) standardize the culture of mesenchymal stem cells and conditioned medium; 2) characterize the experimental model of lung fibrosis induced by bleomycin by optical microscopy before and after treatment with MSC and conditioned medium; 3) to evaluate the expression of serological biomarkers (Fibrinogen, Factor von Willebrand and PDGF); 4) to quantify the expression of proteins related to oxidative stress (NOS), pro-inflammatory and pro-fibrotic (IL-17 and TGF-beta) and pro-angiogenic cytokines (VEGF and endothelin) by immunohistochemistry; and 5) to quantify the deposition of collagen I and V fibers by immunofluorescence. Materials and methods: A total of 44 male albino Wistar rats weighing 250-300g and 8 weeks of age were used. Four experimental groups were composed of 10 animals, which participated in the experiment divided in three moments: D0, D10 and euthanasia (D14 or D21). In D0, orotracheal instillation of bleomycin at the dose of 1.5 U/ kg was performed; in D10 caudal vein infusion of mesenchymal stem cells at the dose of 106 MSC/ kg or 200 ul of conditioned medium was performed. To prepare the MSC, a mean of 1.2 g of adipose tissue was obtained, dissociated with type I collagenase and the mean cell count was 3.05 x 106 lymphomonuclear cells / g of adipose tissue. These cells were cultured for 21 days in DMEM-F12 Knockout medium supplemented with 10% fetal bovine serum. The following three criteria were used to prove the profile of mesenchymal stem cells: plastic adherence, expression of CD90 by flow cytometry ( > 90%) and differentiation capacity in three mesodermal lines. In D10, a pool of these allogeneic cells was infused intravenously into the caudal vein at a concentration of 1 x 106 cells / animal in a volume of 200 ul of saline. In D14 or D21 the animals were euthanized and analyzed for weight and microscopic-laboratory analyzes. Histological analyzes were performed by two different specialists in a double-blind study. The parameters of weight gain and microscopic recovery of lung tissue were analyzed in each group. Results: Our data show that the mesenchymal stem cells derived from the abdominal adipose tissue of Wistar rats had their phenotypic profile, plastic adhesion capacity and differentiation in 3 mesodermal lines established unequivocally, as established internationally by ISSCR. Mesenchymal stem cells and conditioned medium induced: clinical recovery after treatment; bleomycin-induced reversal of inflammation and pulmonary fibrosis; the reversal of arteriopathy in the distal pulmonary parenchyma; the reduction of fibrinogen, von Willebrand factor and PDGF concentrations (serologic markers); decreased expression of oxidizing enzymes; the reduction of endothelin expression and the modulation of the expression of the remodeling protein (IL-17), the activation of TGF-B fibroblasts and the synthesis of collagen. Conclusion: In this study we demonstrated that therapies with mesenchymal stem cells derived from adipose tissue and conditioned medium were effective in the modulation of inflammatory and fibrogenic processes in the bleomycin-induced model, acting to modulate myofibroblastic activation and also in tissue restoration and endothelial cells. In addition, the conditioned medium proved to be as efficient as the stem cells themselves, in effective pulmonary remodeling, and should be considered as a viable and innovative therapeutic proposal
233

Análise dos fatores que influenciam o desenvolvimento da mucosite oral em transplante de células-tronco hematopoiéticas autólogo / Analysis of factors that influence the oral mucositis development in autologous stem cell transplantation

Walmyr Ribeiro de Mello 22 September 2016 (has links)
A mucosite é um efeito grave e dose-limitante do tratamento antineoplásico, cujas lesões ulceradas apresentam grande impacto na morbidade e mortalidade dos pacientes, por apresentar dor, restrição alimentar e servindo como porta de entrada para infecções originadas da mucosa bucal, com incidência variável de acordo com a doença de base, idade, condição de saúde bucal, dose e frequência da quimioterapia. A ocorrência de mucosite oral é frequente nos pacientes que receberam altas doses de quimioterapia seguidas de transplante autólogo de células tronco hematopoiéticas. O objetivo deste estudo foi analisar os fatores que influenciam o desenvolvimento da mucosite oral. Foi realizada uma análise retrospectiva em 413 prontuários de pacientes consecutivos submetidos ao transplante autólogo de células tronco hematopoiéticas e os dados coletados incluíram dados demográficos (sexo, idade, doença de base), dados do TCTH (tipo de transplante, regime de condicionamento) e incidência de mucosite oral. Os resultados deste estudo mostraram que a incidência de mucosite foi maior em pacientes do sexo masculino e nos pacientes do sexo feminino com idade média de 29 anos, nos pacientes submetidos ao regime de condicionamento BU/MEL e naqueles pacientes portadores de LMA. Os resultados deste estudo permitiram concluir que a incidência de mucosite oral na casuística analisada foi maior nos pacientes do sexo masculino; nas mulheres jovens quando analisados sexo e idade separadamente, nos pacientes portadores de LMA e naqueles submetidos ao regime de condicionamento BU/MEL / Oral mucositis remains as a serious and dose-limiting side-effect of antineoplastic treatment and ulcerated lesions lead to a great impact on morbidity and mortality of patients due to pain, food restriction and serving as a gateway to originate infections of the oral mucosa patients. The incidence of oral mucositis remains uncertain and it is variable according to the underlying disease, age, oral health condition, dose and frequency of chemotherapy. The incidence of oral mucositis is high in patients receiving high-dose chemotherapy followed by autologous transplantation of hematopoietic stem cells. The aim of this study was to analyze the factors that influence the development of oral mucositis. a retrospective analysis of 413 medical records of consecutive patients undergoing autologous hematopoietic stem cell transplantation. Data collected included demographic data was performed (sex, age, underlying disease), HSCT data (type of transplant conditioning regimen) and incidence oral mucositis. The results of this study showed that the incidence of mucositis was higher in male patients and female patients with a mean age of 29 years, in patients undergoing conditioning regimen comprises BU / MEL and in those patients with AML. The results of this study showed that the incidence of oral mucositis in the analyzed sample was higher in males; in young women when analyzed separately sex and age, in patients with AML and those submitted to the BU / MEL conditioning regimen
234

Adrenoleucodistrofia ligada ao cromossomo x e estresse oxidativo : papel do transplante de células hematopoiéticas e da interleucina 6

Rockenbach, Francieli Juliana January 2012 (has links)
Objetivos. Avaliar o papel do transplante de células hematopoiéticas (TCH) e da interleucina 6 (IL – 6) sobre vários parâmetros de estresse oxidativo em pacientes com Adrenoleucodistrofia ligada ao cromossomo X (X-ALD). Métodos. A concentração de malondialdeído (MDA), o conteúdo de carbolinas e sulfidrilas e a concentração de ácido hexacosanóico (C26:0) foram quantificados no plasma de pacientes X-ALD antes e após serem submetidos ao TCH. E, a concentração de MDA, a formação de carbonilas e a concentração de IL-6 foram quantificados em plasma e o conteúdo de glutationa reduzida (GSH) foi quantificado em eritrócitos de pacientes X-ALD com fenótipos cerebral infantil (cALD) ou assintomáticos no momento diagnóstico. Resultados. Observamos um aumento significativo na concentração de MDA em plasma de pacientes X-ALD antes e após o TCH em comparação ao grupo controle e uma redução significativa nesses valores após o transplante em comparação aos anteriores ao procedimento. Verificamos uma redução significativa no conteúdo de sulfidrilas no plasma de pacientes X-ALD antes do TCH em comparação ao grupo controle e um aumento significativo desses níveis após o TCH. Não observamos diferenças significativas no conteúdo de carbonilas no plasma de X-ALD antes e após o TCH, em comparação aos controles, apesar de observarmos uma redução significativa nesta determinação nos pacientes após o transplante em relação a antes do TCH. Os pacientes X-ALD apresentam níveis plasmáticos de C26:0 significativamente aumentados antes do TCH em comparação aos controles e, após o TCH, as concentrações de C26:0 foram reduzidas. Observamos uma correlação negativa significativa entre a medida do conteúdo de sulfidrilas e os níveis plasmáticos de C26:0 de indivíduos X-ALD antes do TCH. Também evidenciamos elevados níveis de MDA e da formação de carbonilas no plasma de pacientes cALD e assintomáticos em comparação ao grupo controle. Ainda, observamos redução significativa do conteúdo de GSH nos dois grupos testados comparados aos controles. A quantificação de IL-6 foi significativamente maior nos pacientes cALD, o que não foi observado nos pacientes assintomáticos, apesar destes mostrarem uma tendência de aumento da concentração de IL-6. Conclusões. Os resultados obtidos a partir do plasma de pacientes X-ALD antes e após o TCH demonstram que esta terapia, quando bem indicada e bem sucedida, tem alta efetividade em reduzir a concentração plasmática de C26:0 e é eficaz em reduzir a peroxidação lipídica e o dano oxidativo às proteínas nos pacientes X-ALD. Ainda, é possível relacionar o acúmulo de C26:0 e o dano oxidativo na patogênese da X-ALD. Nossos dados permitem sugerir que a lipoperoxidação e o dano oxidativo às proteínas possam de alguma forma estar envolvidos na fisiopatologia da X-ALD. Além disso, podemos presumir que, nos pacientes X-ALD assintomáticos estudados, o dano oxidativo e os aspectos inflamatórios desempenham papéis importantes na evolução e nas futuras manifestações do fenótipo neuronal. Também podemos supor que a administração de antioxidantes deve ser considerada como uma terapia adjuvante potencial para os pacientes assintomáticos e sintomáticos afetados pela X-ALD, inclusive para aqueles submetidos ao TCH. / Objective. We aimed to evaluate the role of hematopoietic stem cell transplantation (HSCT) and interleukin 6 (IL – 6) on various parameters of oxidative stress in X-linked adrenoleukodystrophy (X-ALD) patients. Methods. Malondialdehyde (MDA), sulfhydryl, carbonyl and hexacosanoic acid (C26:0) levels were measured in plasma from X-ALD patients before and after HSCT. And, MDA, carbonyl and IL-6 levels were measured in plasma and reduced glutathione (GSH) content was measured in erythrocytes from X-ALD patients with different phenotype (asymptomatic and childhood cerebral (CCER patients) at diagnosis moment. Results. We observed increased levels of MDA in plasma from X-ALD before and after HSCT compared to control group, but there was a significant reduction in MDA values after transplantation compared to levels found before the procedure. We verified a significant decrease in sulfhydryl content in plasma of X-ALD patients before HSCT compared with the control group and we also verified a significant increase in the levels of sulfhydryl content after HSCT. No significant differences were observed in carbonyl content in plasma of X-ALD before and after HSCT, compared to controls. However, we observed a significant reduction of plasma carbonyl content from X-ALD patients after HSCT compared to before HSCT. X-ALD patients presented a significant increase of C26:0 plasma level before HSCT when compared to controls and an important reduction of C26:0 plasma concentration in X-ALD patients after HSCT when compared to before HSCT C26:0 levels. We observed an inverse significant correlation between sulfhydryl content and plasma C26:0 levels of X-ALD individuals before HSCT. We also evidenced high levels of MDA and carbonyl formation in plasma from CCER and asymptomatic patients compared to controls. Still, we observed a significant decrease of GSH content in both groups tested compared to controls. The quantification of IL-6 is significantly higher in CCER patients, which is not observed in asymptomatic patients, despite these patients show a tendency of increased concentration of IL-6. Conclusions. The results obtained from plasma of X-ALD patients before and after HSCT demonstrate that this therapy, when well indicated and successful, has high effectiveness in reducing C26:0 plasma and is effective in reducing lipid peroxidation and oxidative damage to proteins in X-ALD patients. Still, it is possible to relate the accumulation of C26:0 and oxidative damage in the pathogenesis of X-ALD. Our data also suggest that lipid peroxidation and protein damage may somehow be involved in the pathophysiology of X-ALD. Moreover, we can assume that in our asymptomatic X-ALD patients, oxidative damage and inflammatory issues seem to play an important role in the evolution and future manifestations of neuronal phenotype. We can also assume that the administration of antioxidants should be considered as a potential adjuvant therapy for asymptomatic and symptomatic patients affected by X-ALD, including those that are submitted to HSCT.
235

Incidence of Vancomycin-Resistant Enterococci (vre) Infection in High-Risk Febrile Neutropenic Patients Colonized with Vre

Bossaer, John B., Hall, Philip D., Garrett-Mayer, Eliabeth 01 February 2011 (has links)
Purpose: This study seeks to determine the incidence of vancomycin-resistant enterococci (VRE) infection in high-risk neutropenic fever patients colonized with VRE and to determine patient characteristics associated with VRE infection. Methods: We conducted a retrospective, single-center, unmatched case-control study. Fifty-three VRE-colonized, high-risk patients with neutropenic fever were identified between January 2006 and February 2009. The two most common diagnoses/conditions included acute myeloid leukemia and hematopoietic stem cell transplantation. Data collected included days of neutropenia, days of fever, demographic data, culture results, and antimicrobial therapy. Results: Twenty of the 53 patients (38%) with VRE colonization developed a VRE infection. The most common VRE infections were bacteremias (26%). The presence of neutropenia lasting longer than 7 days was associated with the development of VRE infection in this high-risk population colonized with VRE. The timeframe to develop VRE infection varied from 1 day to 2 weeks. Conclusion: For patients colonized with VRE, approximately 38% of high-risk neutropenic patients developed a VRE infection. This is the first study to specifically evaluate the incidence of VRE infections in febrile neutropenic patients colonized with VRE. Future research into the use and efficacy of empiric VRE coverage is needed.
236

An investigation into the potential of mesenchymal stromal cells to attenuate graft-versus-host disease

Melinda Elise Christensen Unknown Date (has links)
Survival of patients with poor prognosis or relapsed haematopoietic malignancies can be markedly improved by allogeneic haematopoietic stem cell transplantation (HSCT). HSCT reconstitutes the immune and haematopoietic systems after myeloablative conditioning and inhibits the recurrence of the malignancy by a graft-versus-leukaemia (GVL) response mediated by donor T cells. However, significant post-transplant complications such as graft-versus-host disease (GVHD) continue to plague the event-free survival of this curative procedure. GVHD is facilitated by donor T cells that recognise histocompatibility antigens on host antigen presenting cells (APC), such as dendritic cells (DC). Current treatment options for GVHD are focused on these T cells. However, these treatments result in an increased incidence of infection, graft rejection and relapse. A novel means of immunosuppression in GVHD is the use of multi-potent, mesenchymal stromal cells (MSC). MSC are non-immunogenic cells that actively suppress T cell function in vitro, and can resolve steroid-refractory GVHD in the clinic. Despite their use in the clinic, there is a paucity of pre-clinical data. Our aim was to investigate the in vivo efficacy of MSC to control GVHD while maintaining the beneficial GVL effect, and to begin to understand the mechanism by which MSC exert their immunosuppressive effects. We isolated and characterised MSC from murine bone/bone marrow and demonstrated that they suppressed T cell proliferation in vitro, even at low ratios of 1 MSC per 100 T cells. This was true of both donor-derived MSC, and MSC derived from unrelated donors (third party). Importantly, we observed that MSC significantly reduced T cell production of the pro-inflammatory cytokines TNFα and IFNγ in culture supernatants and that IFNγ plays a key role in the ability of MSC to suppress T cell proliferation. In vivo, we examined the effects of donor-derived MSC on GVHD severity and onset in two myeloablative murine models of HSCT. A major histocompatibility complex (MHC)-mismatched donor-recipient pair combination was used as a proof–of-principle model [UBI-GFP/BL6 (H-2b)àBALB/c (H-2d)], and an MHC-matched, minor histocompatibility antigen (miHA) mismatched donor-recipient pair combination was used to mimic MHC-matched sibling transplantation [UBI-GFP/BL6 (H-2b)àBALB.B (H-2b)]. We examined a number of variables related to MSC infusion including timing, dose and route of injection. We found that early post transplant infusion of MSC by the intraperitoneal injection was most effective at delaying death from GVHD, compared to pre-transplant infusion or intravenous injection. Furthermore, we found that the dose of MSC was critical, as infusion of too few MSC was ineffective and infusion of too many MSC exacerbated the development of GVHD. Taken together, these results suggest that timing, dose and route of injection are all important factors to be considered to ensure successful therapeutic outcome. To investigate the in vivo mechanism of action, we conducted timed sacrifice experiments in the MHC-mismatched model to determine if MSC altered cytokine secretion and cellular effectors, such as DC, known to play a key role in GVHD. Despite the fact that MSC given post-HSCT enter an environment full of activated DC and IFNγ levels, by day 3 and 6 post infusion, these activated DC and IFNγ levels are decreased compared to controls or mice infused with MSC pre-transplant (p<0.05). This confirmed our in vitro data that IFNγ played an important role in MSC-mediated immunosuppression. In addition, when we removed a major source of IFNγ production in vivo by administering the T cell depleting antibody KT3 to mice with or without MSC, we found that although T cell depletion prolonged survival, MSC were unable to further enhance this effect. This was also true when MSC were used in combination with the conventional immunosuppressant cyclosporine. Finally, we examined whether the infusion of MSC would compromise the GVL effect. We found that whilst MSC could delay the onset of GVHD, in our model they did not alter the anti-tumour effects of the donor T cells. Overall, we have shown that MSC can delay but not prevent death from GVHD when administered at an appropriate time and dose and that IFNγ is required for MSC-mediated immunosuppression in our model. These data suggest that patients undergoing HSCT should be monitored for IFNγ, and administered MSC when high levels are reached. Whilst MSC may be a promising therapy for patients with severe GVHD, we highlight that further investigation is warranted before MSC are accepted for widespread use in the clinic. The risks and benefits for transplant recipients should be carefully considered before utilising MSC to treat or prevent GVHD.
237

Patienters smärtupplevelser i samband med stamcellstransplantation

Gustafsson, Anna, Fernström, Marie January 2009 (has links)
<h1>Abstract</h1><p><strong>Background: </strong>Pain is usually common patients who undergo high-dose treatment in combination with HSCT. Pain is usually associated with side effects as for example mucositis. The purpose of this study was to examine patients’ experiences of pain in relation to stemcellstransplantation. The purpose was also to examine how patients experience that they have been treated by the personnel regarding their pain, and also if the pain relief correspond to the patients expectations.</p><p><strong>Method: </strong>The study is a descriptive, longitudinal study. Eight patients who underwent HSCT were interviewed. The study implemented in three parts, whereof two interviews and one questionnaire. The interview material was analyzed by means of content analysis.</p><p><strong>Results: </strong>The result shows that five of eight patients experienced pain during HSCT treatment. Three of these informants experienced pain in their mouth, their head and in their stomach. This is usually commonly side effects of the treatment. Back pain occurs in two of the patients and this pain hasn’t proceeded during the treatment.</p><p>Three informants did not experience any pain at all during the time of nursing. The result even shows that the all of the informants had experienced a well refutation of the personnel in terms of their pain. All informants reported that it was important to be well pain relieved. Those informants who had pain during their treatment were very satisfied with the pain relief they have got.</p><p><strong> </strong></p><p><strong>Keywords: </strong>stem cell transplantation, oral pain, pain treatment, oral mucositis, satisfaction with care.</p> / <p> </p><h1>Sammanfattning</h1><p><strong>Bakgrund och syfte: </strong>Smärta är vanligt förekommande bland patienter som genomgår högdosbehandling i kombination med HSCT. Smärta är vanligtvis förknippad med biverkningar som t ex mucosit. Syftet med denna studie var att undersöka patienters upplevelse av smärta i samband med stamcellstransplantation. Syftet är även att undersöka hur patienterna upplever att de blir bemötta av personalen angående sin smärta, samt om smärtlindringen motsvarar patientens förväntningar.</p><p><strong>Metod:</strong> Studien är en deskriptiv, longitudinell studie. Åtta patienter som skulle genomgå stamcellstransplantation intervjuades. Studien genomfördes i tre delar, varav två intervjuer och ett frågeformulär. Intervjumaterialet analyserades med innehållsanalys.</p><p><strong>Resultat:</strong> Resultatet visar att fem av åtta patienter upplevde smärta i samband med HSCT. Tre av dessa informanter upplevde smärtor i munnen, huvudet och i magen. Ryggsmärta förekom hos två av informanterna och denna smärta hade inte uppstått i samband med behandlingen. Tre informanter upplevde ingen smärta alls under hela vårdtiden. Resultatet visar även att samtliga informanter upplevt ett bra bemötande av personalen vad gäller deras smärta. Alla informanter uppgav att det var viktigt att vara bra smärtlindrad. De informanter som hade smärta under behandlingen var mycket nöjda med den smärtlindring de fick.</p><p><strong> </strong></p><p><strong>Nyckelord: </strong>stamcellstransplantation, oral smärta, smärtbehandling, oral mucosit, tillfredsställelse med vård.</p>
238

Using Minisequencing Technology for Analysing Genetic Variation in DNA and RNA

Fredriksson, Mona January 2005 (has links)
<p>In this thesis, the four-color fluorescence tag-microarray minisequencing system pioneered by our group was further developed and applied for analysing genetic variation in human DNA and RNA. A SNP marker panel representing different chromosomal regions was established and used for identification of informative SNP markers for monitoring chimerism after stem cell transplantation (SCT). The success of SCT was monitored by measuring the allelic ratios of informative SNPs in follow-up samples from nine patients with leukaemia. The results agreed with data obtained using microsatellite markers. Further the same SNP marker panel was used for evaluation of two whole genome amplification methods, primer extension preamplification (PEP) and multiple displacement amplification (MDA) in comparison with genomic DNA with respect to SNP genotyping success and accuracy in tag-array minisequencing. Identical results were obtained from MDA products and genomic DNA.</p><p>The tag-microarray minisequencing system was also established for multiplexed quantification of imbalanced expression of SNP alleles. Two endothelial cell lines and a panel of ten coding SNPs in five genes were used as model system. Six heterozygous SNPs were genotyped in RNA (cDNA) from the cell lines. Comparison of the relative amounts of the SNPs alleles in cDNA to heterozygote SNPs in genomic DNA displayed four SNPs with significant imbalanced expression between the SNP alleles. Finally, the tag-array minisequencing system was modified for detection of splice variants in mRNA from five leukaemia cell lines. A panel of 20 cancer-related genes with 74 alternatively splice variants was screened. Over half of the splice variants were detected in the cell lines, and similar alternative splicing patterns were observed in each cell line. The results were verified by size analysis of the PCR product subjected to the minisequencing primer extension reaction. The data from both methods agreed well, evidencing for a high sensitivity of our system.</p>
239

Acute Lymphoblastic Leukaemia in Adult Patients : Studies of Prognostic Factors, Treatment Results and in vitro Cellular Drug Resistance

Hallböök, Helene January 2005 (has links)
<p>Treatment results and clinical characteristics in adult acute lymphoblastic leukaemia (ALL) were evaluated regarding three issues: a new treatment with cytarabine up-front, stem cell transplantation and a comparison between adult and paediatric treatment protocols. All studies were conducted on a national basis. Furthermore, activity of imatinib was investigated by in vitro cytotoxicity assay. </p><p>The national protocol was evaluated in 153 adult ALL patients. A high complete remission rate, 86%, was achieved with 29% overall survival at 3-years. Favourable outcome was identified in patients < 40 years with precursor B phenotype and continuous complete remission was higher for precursor B compared to T-ALL. </p><p>Stem cell transplantation was evaluated in 187 patients. No differences in outcome between allogeneic and autologous transplantation were found, with the exception of Philadelphia-positive ALL, in which allogeneic transplantation was preferable. Limited chronic graft-versus-host disease (compared to none) resulted in superior disease free survival. </p><p>The paediatric NOPHO-92 and the Adult protocols were evaluated for 243 ALL-patients. Superior remission rate and survival were achieved for 10-18 year-olds treated according to the Paediatric protocol compared to both 15-25 and 25-40 year-olds treated according to the Adult protocol. Treatment protocol was a significant prognostic factor for patients aged 15-20 years. </p><p>Fluorometric Microculture Cytotoxicity Assey was used to analyze 15 tumour cell samples from ALL patients. High concordance was determined between in vitro sensitivity to imatinib and presence of BCR-ABL. Daunorubicin, prednisolone and cytarabine had the greatest benefit from a combination with imatinib. </p><p>The national adult treatment protocol’s results were consistent with international trials regarding precursor B ALL but may be under performing for T-ALL. Adolescents may benefit from treatment according to the Paediatric protocol. No difference in outcome between allogeneic and autologous stem cell transplantation was determined except for Philadelphia-positive patients, despite the indication of a graft-versus-leukaemia effect.</p>
240

Using Minisequencing Technology for Analysing Genetic Variation in DNA and RNA

Fredriksson, Mona January 2005 (has links)
In this thesis, the four-color fluorescence tag-microarray minisequencing system pioneered by our group was further developed and applied for analysing genetic variation in human DNA and RNA. A SNP marker panel representing different chromosomal regions was established and used for identification of informative SNP markers for monitoring chimerism after stem cell transplantation (SCT). The success of SCT was monitored by measuring the allelic ratios of informative SNPs in follow-up samples from nine patients with leukaemia. The results agreed with data obtained using microsatellite markers. Further the same SNP marker panel was used for evaluation of two whole genome amplification methods, primer extension preamplification (PEP) and multiple displacement amplification (MDA) in comparison with genomic DNA with respect to SNP genotyping success and accuracy in tag-array minisequencing. Identical results were obtained from MDA products and genomic DNA. The tag-microarray minisequencing system was also established for multiplexed quantification of imbalanced expression of SNP alleles. Two endothelial cell lines and a panel of ten coding SNPs in five genes were used as model system. Six heterozygous SNPs were genotyped in RNA (cDNA) from the cell lines. Comparison of the relative amounts of the SNPs alleles in cDNA to heterozygote SNPs in genomic DNA displayed four SNPs with significant imbalanced expression between the SNP alleles. Finally, the tag-array minisequencing system was modified for detection of splice variants in mRNA from five leukaemia cell lines. A panel of 20 cancer-related genes with 74 alternatively splice variants was screened. Over half of the splice variants were detected in the cell lines, and similar alternative splicing patterns were observed in each cell line. The results were verified by size analysis of the PCR product subjected to the minisequencing primer extension reaction. The data from both methods agreed well, evidencing for a high sensitivity of our system.

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