Ulm, Univ., Diss., 2008.

Thesis (Ph. D.)--School of Pharmacy and Dept. of Chemistry. University of Missouri--Kansas City, 2008. / "A dissertation in pharmaceutical sciences and chemistry." Advisor: Ashim K. Mitra. Typescript. Vita. Description based on contents viewed Sept. 12, 2008; title from "catalog record" of the print edition. Includes bibliographical references (leaves 193-204). Online version of the print edition.

Certaines mutations de rôle inconnu dans le gène UL97 du cytomégalovirus humain ont été retrouvées dans une étude clinique comparant l'efficacité du ganciclovir et du valganciclovir oral administrés chez des patients transplantés d'organe solide. Sans isolât clinique, il est difficile de distinguer les mutations associées à la résistance, les mutations associées au polymorphisme viral et les mutations compensatrices. L'objectif de ce projet de maîtrise consiste à caractériser les mutations détectées dans le gène UL97 à l'aide de la technologie des chromosomes bactériens artificiels. Pour évaluer le rôle de ces mutations, une méthode a été développée pour générer des virus recombinants mutants. Des cellules humaines permissives ont été transfectées avec l'ADN de virus recombinants mutants clones dans un chromosome bactérien artificiel. La sensibilité au ganciclovir des virus reconstitués a ensuite été évaluée. Les mutations de rôle inconnu retrouvées dans l'étude clinique semblent associées au polymorphisme viral.

Thèse de doctorat : Pharmacologie : Nancy 1 : 2008. / Titre provenant de l'écran-titre.

Les infections par cytomégalovirus sont un problème majeur en transplantation rénale du fait de l’augmentation du risque de perte de greffon et de l’augmentation de la morbi-mortalité des patients. Toutefois la mise en place d’un traitement prophylactique par ganciclovir a significativement fait diminuer l’incidence de ces infections. Cette efficacité est toutefois limitée par une importante hématotoxicité notamment des neutropénies. La survenue de cet évènement indésirable conduit à une réduction des doses voire à un arrêt du traitement, favorisant ainsi l’émergence de résistances virales. Ces résistances sont un problème grandissant chez les personnes transplantées du fait du manque de protocole de prise en charge de celles-ci. Dans ce contexte notre objectif était de mieux comprendre la survenue et le mécanisme de cette toxicité. Dans un premier temps nous avons étudié le métabolisme intracellulaire du ganciclovir chez des patients. Nous avons remarqué qu’il y a une forte corrélation entre l’exposition à la forme active du ganciclovir et la diminution du nombre de neutrophiles au 3ème mois de traitement. Nous avons par la suite étudié l’impact de variations génétiques sur des transporteurs. Nous avons remarqué qu’un polymorphisme était fortement associé à une diminution du nombre de neutrophiles et qu’il entrainait également une augmentation de la concentration intracellulaire de ganciclovir à l’aide d’un modèle in vitro. Cette thèse fournit de nouveaux outils d’exploration du métabolisme et de l’accumulation intracellulaire du ganciclovir qui pourraient être utiles pour la prévention de la survenue de neutropénies sous ganciclovir. / Cytomegalovirus infection is a major issue in transplant patients as it affects the graft survival and contributes to patients’ morbi-mortality. The implementation of ganciclovir prophylaxis has significantly decreased its incidence, however GCV frequently induces neutropenia. This adverse effect leads to a decrease in the ganciclovir dose or to a discontinuation of the therapy, thereby favoring viral resistance. Resistance to ganciclovir is a growing problem in solid organ transplantion because of the lack of proper data to support treatment decisions when it is encountered. In this context we aim at better understanding the factors involved in this toxicity. First we explored the intracellular metabolism of ganciclovir in patients’ white blood cells. We found that the active form of ganciclovir is associated with neutrophil toxicity at month 3 of treatment. Then we explored the effect of targeted polymorphisms among transporter genes in two cohorts of renal transplant patients. We found that a single nucleotide polymorphism is strongly associated with a decrease in the neutrophil count and in ganciclovir intracellular accumulation. This thesis provides relevant tools for a deeper exploration of ganciclovir intracellular metabolism and accumulation which might be useful for the prevention of ganciclovir induced neutropenia.

Thesis (Ph. D.)--School of Pharmacy and Dept. of Chemistry. University of Missouri--Kansas City, 2005. / "A dissertation in pharmaceutical science and chemistry." Advisor: Ashim K. Mitra. Typescript. Vita. Description based on contents viewed Mar. 12, 2007; title from "catalog record" of the print edition. Includes bibliographical references (leaves 138-147). Online version of the print edition.

Thesis (Ph. D.)--School of Pharmacy. University of Missouri--Kansas City, 2005. / "A dissertation in pharmaceutical sciences and pharmacology." Advisor: Ashim K. Mitra. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed June 26, 2006. Includes bibliographical references (leaves 174-192). Online version of the print edition.

Objetivo: comparar a profilaxia universal com a terapia preemptiva com ganciclovir endovenoso no manejo da citomegalovirose em pacientes transplantados de pulmão em uma coorte retrospectiva. Metodologia: de março de 1999 a dezembro de 2009 foram estudados, no Serviço de Transplante do Complexo Hospitalar Santa Casa de Porto Alegre, todos os pacientes submetidos a transplante pulmonar, procurando-se verificar a ocorrência de citomegalovirose relacionada ao tipo de tratamento profilático anti-viral utilizado (universal e preemptiva). Foram excluídos, em ambos os grupos, os pacientes nos quais não tivesse sido registrada a antigenemia no primeiro mês após o transplante, e os que foram a óbito dentro dos primeiros trinta dias após a cirurgia. Resultados: de 224 pacientes transplantados no período referido, 66 (29,5%) foram excluídos por óbito precoce. Os 158 pacientes que entraram no estudo tinham idade de 51±15 anos (7 anoa-71 anos), e 61,0% eram do sexo masculino; 150 (95%) receberam o órgão de doador cadavérico, e 134 (85,0%) foram submetidos a transplante unilateral. A profilaxia universal para citomegalovirus (CMV) foi realizada em 70 pacientes (44,0%) e a terapia preemptiva em 88 (56,0%). O grupo que recebeu profilaxia universal levou maior tempo para positivar o exame (p<0.001) comparado com o grupo que não a recebeu. Houve associação significativa entre profilaxia e antigenemia positiva no primeiro ano após o transplante (p=0.024). A mortalidade no primeiro e no quinto ano foi respectivamente de 20% e 50%. A sobrevida mediana do grupo com profilaxia universal foi 3.8 anos (IC95% de 2.5 a 5.0) e o grupo com terapia preemptiva de 4,3 anos (IC95% de 2.5 a 6.0), não apresentando diferença significativa. Conclusão: com base nos dados obtidos neste estudo a profilaxia universal e a terapia preemptiva demonstraram-se seguras e efetivas, entretanto os achados desta pesquisa não se demonstraram conclusivos para definir a melhor opção terapêutica. / Objective: To compare the universal prophylaxis and preemptive therapy for the treatment of cytomegalovirus in lung transplant patients in a retrospective cohort. Method: Performed at the Lung Transplant service in Santa Casa de Porto Alegre during the period from March 1999 to December 2009, upon reviewing the records and results of cytomegalovirus detection. Were excluded in both groups the patients who were not registered antigenemia in the first month after lung transplantation, due to death during this period. Results: 224 patients transplanted during the study period, 66 patients were excluded due to death within 30 days after transplantation. Mean age of patients was 51 ± 15 years old, 61.0% were men, 95.0% received organ of cadaveric donors, 85.0% were submited to unilateral transplant. The universal prophylaxis was performed in 44.0% of patients and preemptive therapy in 56.0%. The group receiving prophylaxis universal took longer to make positive antigenemia (p <0.001) when compared with the group not receiving prophylaxis. It was observed significant association between positive antigenemia and prophylaxis in the first year after transplantation (p = 0.024). The general mortality in the first and fifth year was 20.0% and 50.0% respectively. Survival of patients with prophylaxis presented a median of 3.8 (95% CI 2,5 to 5.0) years and the group that received no prophylaxis had a survival of 4,3 years (95% CI 2.5 to 6.0). Conclusion: Based on the data obtained in this study universal prophylaxis and preemptive therapy demonstrated to be safe and effective, however the findings of this research did not prove conclusive to determine the best treatment.

Objetivo: comparar a profilaxia universal com a terapia preemptiva com ganciclovir endovenoso no manejo da citomegalovirose em pacientes transplantados de pulmão em uma coorte retrospectiva. Metodologia: de março de 1999 a dezembro de 2009 foram estudados, no Serviço de Transplante do Complexo Hospitalar Santa Casa de Porto Alegre, todos os pacientes submetidos a transplante pulmonar, procurando-se verificar a ocorrência de citomegalovirose relacionada ao tipo de tratamento profilático anti-viral utilizado (universal e preemptiva). Foram excluídos, em ambos os grupos, os pacientes nos quais não tivesse sido registrada a antigenemia no primeiro mês após o transplante, e os que foram a óbito dentro dos primeiros trinta dias após a cirurgia. Resultados: de 224 pacientes transplantados no período referido, 66 (29,5%) foram excluídos por óbito precoce. Os 158 pacientes que entraram no estudo tinham idade de 51±15 anos (7 anoa-71 anos), e 61,0% eram do sexo masculino; 150 (95%) receberam o órgão de doador cadavérico, e 134 (85,0%) foram submetidos a transplante unilateral. A profilaxia universal para citomegalovirus (CMV) foi realizada em 70 pacientes (44,0%) e a terapia preemptiva em 88 (56,0%). O grupo que recebeu profilaxia universal levou maior tempo para positivar o exame (p<0.001) comparado com o grupo que não a recebeu. Houve associação significativa entre profilaxia e antigenemia positiva no primeiro ano após o transplante (p=0.024). A mortalidade no primeiro e no quinto ano foi respectivamente de 20% e 50%. A sobrevida mediana do grupo com profilaxia universal foi 3.8 anos (IC95% de 2.5 a 5.0) e o grupo com terapia preemptiva de 4,3 anos (IC95% de 2.5 a 6.0), não apresentando diferença significativa. Conclusão: com base nos dados obtidos neste estudo a profilaxia universal e a terapia preemptiva demonstraram-se seguras e efetivas, entretanto os achados desta pesquisa não se demonstraram conclusivos para definir a melhor opção terapêutica. / Objective: To compare the universal prophylaxis and preemptive therapy for the treatment of cytomegalovirus in lung transplant patients in a retrospective cohort. Method: Performed at the Lung Transplant service in Santa Casa de Porto Alegre during the period from March 1999 to December 2009, upon reviewing the records and results of cytomegalovirus detection. Were excluded in both groups the patients who were not registered antigenemia in the first month after lung transplantation, due to death during this period. Results: 224 patients transplanted during the study period, 66 patients were excluded due to death within 30 days after transplantation. Mean age of patients was 51 ± 15 years old, 61.0% were men, 95.0% received organ of cadaveric donors, 85.0% were submited to unilateral transplant. The universal prophylaxis was performed in 44.0% of patients and preemptive therapy in 56.0%. The group receiving prophylaxis universal took longer to make positive antigenemia (p <0.001) when compared with the group not receiving prophylaxis. It was observed significant association between positive antigenemia and prophylaxis in the first year after transplantation (p = 0.024). The general mortality in the first and fifth year was 20.0% and 50.0% respectively. Survival of patients with prophylaxis presented a median of 3.8 (95% CI 2,5 to 5.0) years and the group that received no prophylaxis had a survival of 4,3 years (95% CI 2.5 to 6.0). Conclusion: Based on the data obtained in this study universal prophylaxis and preemptive therapy demonstrated to be safe and effective, however the findings of this research did not prove conclusive to determine the best treatment.

Objetivo: comparar a profilaxia universal com a terapia preemptiva com ganciclovir endovenoso no manejo da citomegalovirose em pacientes transplantados de pulmão em uma coorte retrospectiva. Metodologia: de março de 1999 a dezembro de 2009 foram estudados, no Serviço de Transplante do Complexo Hospitalar Santa Casa de Porto Alegre, todos os pacientes submetidos a transplante pulmonar, procurando-se verificar a ocorrência de citomegalovirose relacionada ao tipo de tratamento profilático anti-viral utilizado (universal e preemptiva). Foram excluídos, em ambos os grupos, os pacientes nos quais não tivesse sido registrada a antigenemia no primeiro mês após o transplante, e os que foram a óbito dentro dos primeiros trinta dias após a cirurgia. Resultados: de 224 pacientes transplantados no período referido, 66 (29,5%) foram excluídos por óbito precoce. Os 158 pacientes que entraram no estudo tinham idade de 51±15 anos (7 anoa-71 anos), e 61,0% eram do sexo masculino; 150 (95%) receberam o órgão de doador cadavérico, e 134 (85,0%) foram submetidos a transplante unilateral. A profilaxia universal para citomegalovirus (CMV) foi realizada em 70 pacientes (44,0%) e a terapia preemptiva em 88 (56,0%). O grupo que recebeu profilaxia universal levou maior tempo para positivar o exame (p<0.001) comparado com o grupo que não a recebeu. Houve associação significativa entre profilaxia e antigenemia positiva no primeiro ano após o transplante (p=0.024). A mortalidade no primeiro e no quinto ano foi respectivamente de 20% e 50%. A sobrevida mediana do grupo com profilaxia universal foi 3.8 anos (IC95% de 2.5 a 5.0) e o grupo com terapia preemptiva de 4,3 anos (IC95% de 2.5 a 6.0), não apresentando diferença significativa. Conclusão: com base nos dados obtidos neste estudo a profilaxia universal e a terapia preemptiva demonstraram-se seguras e efetivas, entretanto os achados desta pesquisa não se demonstraram conclusivos para definir a melhor opção terapêutica. / Objective: To compare the universal prophylaxis and preemptive therapy for the treatment of cytomegalovirus in lung transplant patients in a retrospective cohort. Method: Performed at the Lung Transplant service in Santa Casa de Porto Alegre during the period from March 1999 to December 2009, upon reviewing the records and results of cytomegalovirus detection. Were excluded in both groups the patients who were not registered antigenemia in the first month after lung transplantation, due to death during this period. Results: 224 patients transplanted during the study period, 66 patients were excluded due to death within 30 days after transplantation. Mean age of patients was 51 ± 15 years old, 61.0% were men, 95.0% received organ of cadaveric donors, 85.0% were submited to unilateral transplant. The universal prophylaxis was performed in 44.0% of patients and preemptive therapy in 56.0%. The group receiving prophylaxis universal took longer to make positive antigenemia (p <0.001) when compared with the group not receiving prophylaxis. It was observed significant association between positive antigenemia and prophylaxis in the first year after transplantation (p = 0.024). The general mortality in the first and fifth year was 20.0% and 50.0% respectively. Survival of patients with prophylaxis presented a median of 3.8 (95% CI 2,5 to 5.0) years and the group that received no prophylaxis had a survival of 4,3 years (95% CI 2.5 to 6.0). Conclusion: Based on the data obtained in this study universal prophylaxis and preemptive therapy demonstrated to be safe and effective, however the findings of this research did not prove conclusive to determine the best treatment.