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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.
61

Molecular techniques for therapeutic and diagnostic applications in Mucopolysaccharidosis IIIB and Gaucher disease

Christensen, Chloe L. 22 December 2020 (has links)
There is an unmet need to develop and test treatments for rare lysosomal disease (LD). Most LDs are present in childhood and do not currently have approved therapies. Rare diseases individually are uncommon but taken together account for a population prevalence of 3.5-5.9% worldwide. Due to their rarity, it often takes significant time and effort to diagnose rare diseases. New diagnostic tools, especially for early detection, will offer an advantage in avoiding this diagnostic odyssey. This dissertation is focused on investigating novel diagnostic and treatment methods in vitro for two neurodegenerative LDs: Gaucher disease (GD) and mucopolysaccharidosis IIIB (MPS IIIB). Mutations in NAGLU and GBA1, the genes that encode for lysosomal hydrolases required for degradation of heparan sulfate and glucocerebrosides, lead to the observed pathogenesis in MPS IIIB and GD, respectively. Since many LDs, including MPS IIIB and some forms of GD, are neurodegenerative, cell and gene-based therapeutic strategies are of significant interest. Therapeutics that offer some symptom mitigation in other LDs, such as enzyme replacement or substrate reduction therapies, do not offer appreciable disease mitigation in MPS IIIB or neurodegenerative GD. Here, a novel compound heterozygous mutation, NAGLUY140C/R297X, that results in approximately 50% residual NAGLU protein and 0.6% NAGLU enzyme activity is reported in NAGLU. Furthermore, a RFLP and site-directed mutagenesis strategy was developed to identify the presence of the relatively common p.R297X mutation in patient cell samples, in addition to two other novel molecular assays for the detection of the p.E153K mutation in NAGLU and p.N370S mutation in GBA1. MPS IIIB and GD human skin fibroblasts were reprogrammed to iPSCs using non-integrating Sendai viral vectors with a reprogramming efficiency of 0.2% and 0.3%, respectively. Resulting iPS cell lines were confirmed as being pluripotent through a barrage of analyses for markers of pluripotency and differentiation. Intriguingly, early passage MPS IIIB iPSCs were found to exhibit increased cell death and spontaneous differentiation to embryoid body-like structures, which was hypothesized to be caused by fibroblast growth factor 2 (FGF2) sequestration or degradation due to inherent heparan sulfate dysregulation. Supplemental FGF2 (100 ng/mL) was found to significantly increase confluency of MPS IIIB iPSCs after 48 hours (n = 5, p ≤ 0.05) and persisting to 96 hrs (n = 5, p ≤ 0.05), thus providing evidence for an important role of FGF2-heparan sulfate interactions in the maintenance of stem cell pluripotency. These findings highlight the importance of considering inherent disease pathology when developing disease models. Three genome editing strategies, CRISPR-Cas9, base and prime editing, are addressed throughout this dissertation. Genome editing outcomes in NAGLU and GBA1, as well as a control gene, HPRT1, are reported in HEK293 cells, human skin fibroblasts, and induced pluripotent stem cells (iPSCs). Although CRISPR-HDR failed to yield mutation correction, base editing of the common p.N370S (c.1226 A>G) in GD skin fibroblasts using with 42% efficiency is reported. Base editing of HPRT1 in HEK293 cells with an overall editing efficiency of 6 ± 0.5% (n = 3), but interestingly, when base editing at the centered nucleotide was analyzed, the editing efficiency increases to 27 ± 4.3% (n = 3). These findings align with other reports of a centered nucleotide preference for base editors and will help direct genome editing strategies in the future. This dissertation describes the first genome editing in NAGLU, and the first base editing in GBA1, and underscores the importance of optimizing genome editing strategies when targeting disease-causing mutations in patient-derived cells. The findings reported here will direct future genome editing strategies for developing cell and gene-based therapies for MPS IIIB and GD. / Graduate / 2021-12-15
62

Pain and Fatigue Associated with Generalized Joint Hypermobility in Gaucher Disease

Mahan, Farrah R., B.A. 21 September 2018 (has links)
No description available.
63

Clonagem e expressão da glucocerebrosidase humana em células de ovário de hamster chinês (CHO). / Cloning and expression of human glucocerebrosidase in Chinese hamster ovary (CHO) cells.

Novo, Juliana Branco 24 June 2010 (has links)
Deficiência na enzima lisossomal glucocerebrosidase (GCR) resulta na doença de Gaucher. O tratamento atual consiste na administração da enzima exógena, produzida em células CHO. Porém, o medicamento disponível no mercado é extremamente custoso. Neste trabalho, propusemos a clonagem e a expressão da GCR humana em células CHO, visando a obtenção de um clone celular produtor para viabilizar a produção futura da enzima, a um custo menor, no Instituto Butantan. A expressão estável da GCR recombinante foi obtida a partir da transfecção de células CHO-dhfr- com o plasmídeo pED de expressão em células de mamíferos contendo o cDNA da GCR, seguido de amplificação gênica por MTX. A GCR foi detectada no extrato celular (~ 64 kDa) e secretada para o sobrenadante (63-69 kDa) em ensaios de western blotting, usando o anticorpo policlonal anti-GCR gerado neste trabalho. A enzima secretada hidrolisou o substrato 4-MUG e a sua produtividade foi estimada em 5,14 pg/célula/dia para o melhor subclone produtor, selecionado para a produção futura da GCR em larga escala. / Deficiency of the lysosomal glucocerebrosidase (GCR) enzyme results in Gaucher\'s disease. Current treatment consists on enzyme replacement therapy by the administration of recombinant GCR produced in CHO cells. However, the medicine available in the market is extremely expensive. In this work, we proposed the cloning and expression of human GCR in CHO cells, in order to obtain a productive cellular clone for future production of GCR enzyme at a lower cost at the Butantan Institute. The stable expression of recombinant GCR was obtained after transfection of CHO-dhfr- cells with pED mammalian expression vector containing the GCR cDNA, followed by gene amplification with MTX. The GCR was detected by western blotting analysis, either as cell-associated (~ 64 kDa) or as secreted forms (63-69 kDa), using the anti-GCR polyclonal antibody produced in this work. The secreted enzyme was active on 4-MUG and was produced at a level of about 5,14 pg/cell/day for the best producer subclone, selected for subsequent steps of GCR production on large scale in next future.
64

Clonagem e expressão da glucocerebrosidase humana em células de ovário de hamster chinês (CHO). / Cloning and expression of human glucocerebrosidase in Chinese hamster ovary (CHO) cells.

Juliana Branco Novo 24 June 2010 (has links)
Deficiência na enzima lisossomal glucocerebrosidase (GCR) resulta na doença de Gaucher. O tratamento atual consiste na administração da enzima exógena, produzida em células CHO. Porém, o medicamento disponível no mercado é extremamente custoso. Neste trabalho, propusemos a clonagem e a expressão da GCR humana em células CHO, visando a obtenção de um clone celular produtor para viabilizar a produção futura da enzima, a um custo menor, no Instituto Butantan. A expressão estável da GCR recombinante foi obtida a partir da transfecção de células CHO-dhfr- com o plasmídeo pED de expressão em células de mamíferos contendo o cDNA da GCR, seguido de amplificação gênica por MTX. A GCR foi detectada no extrato celular (~ 64 kDa) e secretada para o sobrenadante (63-69 kDa) em ensaios de western blotting, usando o anticorpo policlonal anti-GCR gerado neste trabalho. A enzima secretada hidrolisou o substrato 4-MUG e a sua produtividade foi estimada em 5,14 pg/célula/dia para o melhor subclone produtor, selecionado para a produção futura da GCR em larga escala. / Deficiency of the lysosomal glucocerebrosidase (GCR) enzyme results in Gaucher\'s disease. Current treatment consists on enzyme replacement therapy by the administration of recombinant GCR produced in CHO cells. However, the medicine available in the market is extremely expensive. In this work, we proposed the cloning and expression of human GCR in CHO cells, in order to obtain a productive cellular clone for future production of GCR enzyme at a lower cost at the Butantan Institute. The stable expression of recombinant GCR was obtained after transfection of CHO-dhfr- cells with pED mammalian expression vector containing the GCR cDNA, followed by gene amplification with MTX. The GCR was detected by western blotting analysis, either as cell-associated (~ 64 kDa) or as secreted forms (63-69 kDa), using the anti-GCR polyclonal antibody produced in this work. The secreted enzyme was active on 4-MUG and was produced at a level of about 5,14 pg/cell/day for the best producer subclone, selected for subsequent steps of GCR production on large scale in next future.
65

Purifica??o da enzima glucocerebrosidase humana produzida no leite do primeiro clone caprino transg?nico da Am?rica Latina

Wagner, Elisamar Santos Marin 01 March 2016 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-10-20T16:27:57Z No. of bitstreams: 1 DIS_ELISAMAR_SANTOS_MARIN_WAGNER_COMPLETO.pdf: 909420 bytes, checksum: 855d83fc62f091978eab516fd6b1df35 (MD5) / Made available in DSpace on 2016-10-20T16:27:57Z (GMT). No. of bitstreams: 1 DIS_ELISAMAR_SANTOS_MARIN_WAGNER_COMPLETO.pdf: 909420 bytes, checksum: 855d83fc62f091978eab516fd6b1df35 (MD5) Previous issue date: 2016-03-01 / Gaucher disease, first described in 1882, is a rare autosomal recessive genetic disorder characterized by a deficiency of glucocerebrosidase, an enzyme that catalyses the hydrolysis of lysosomal glucocerebroside into glucose and ceramide. The presence of two mutant alleles located on chromosome 1 q21 region confirms the diagnosis of Gaucher disease, with N370S and L444P being the most common mutations. Clinical characteristics commonly associated with Gaucher disease include hepatosplenomegaly, anemia, thrombocytopenia and bone involvement, hematological and neurological impairment in type II and III. The accumulation of mutant enzyme and subsequent depletion of normal enzyme can be treated with enzyme replacement therapy using recombinant glucocerebrosidase. Enzyme replacement therapy is quite effective in the treatment of this disease, often reversing the cascade of biochemical events that lead to clinical manifestations and improving many of the patient's signs and symptoms. There are three recombinant enzymes for enzyme replacement therapy in Gaucher disease: Velaglucerase alfa, Alfataliglucerase and Imiglucerase. These enzymes differ from each other mainly in relation to the form of production, the amino acid sequence, and the glycosylation pattern. Currently, enzyme replacement therapy is administered by a drug called Cerezyme? (imiglucerase), produced by recombinant DNA technology using cell cultures obtained from Chinese hamster ovary. The imiglucerase differs from natural glucocerebrosidase, from placental origin, by an amino acid at position 495, where histidine is replaced with arginine. However, the cost of Cerezyme? is very high, hindering access to therapy. In Brazil, there are nearly 600 carriers of the disease. Although the treatment is guaranteed by law to all patients, the expenses on the purchase of the medicine are very high. The cost could be considerably reduced if the enzyme could be produced in an alternative way. Studies have shown that advanced reproductive techniques allow transgenic animals to be used as bioreactors for production of recombinant proteins of high potential biological and pharmaceutical interest. The Molecular Biology Laboratory and the development of University of Fortaleza in partnership with Quatro G developed the first Latin America transgenic goat clone, whose mammary gland is used as a bioreactor for producing recombinant protein human glucocerebrosidase. This study presented an alternative of glucocerebrosidase enzyme purification. The alternative method was achieved by using milk obtained through an induced lactation of the transgenic and cloned goat. According to the results, one can create a positive expectation for glucocerebrosidase through the procedure cited throughout this study. The confirmation of the presence of glucocerebrosidase enzyme activity was carried out by fluorimetry test. Cerezyme? and goat?s milk control (not genetically modified) were used with positive and negative control, respectively. The objective of this study was to establish protocols for purification of glucocerebrosidase enzyme from the cloned and transgenic goat's milk and confirm the enzyme activity, to evaluate the expression of the enzyme by electrophoresis, and to characterize the recombinant protein by mass spectrometry. / A doen?a de Gaucher, descrita pela primeira vez em 1882, ? uma rara desordem gen?tica autoss?mica recessiva caracterizada pela defici?ncia da atividade da glucocerebrosidase, uma enzima lisossomal que catalisa a hidr?lise de glucocerebros?deo em glicose e ceramida. A presen?a de dois alelos mutantes localizado na regi?o q21 do cromossomo 1 confirma o diagn?stico, sendo as muta??es mais comuns s?o N370S e L444P. O ac?mulo desta enzima pode ser tratada com terapia de reposi??o enzim?tica, usando glucocerebrosidase recombinante, bastante eficaz no tratamento da doen?a, revertendo toda a cascata de eventos bioqu?micos que acabam por ocasionar as manifesta??es cl?nicas apresentadas pelos pacientes ou melhorando muitos dos seus sinais e sintomas. As caracter?sticas cl?nicas comumente associados com a doen?a de Gaucher incluem hepatoesplenomegalia, anemia, trombocitopenia e envolvimento ?sseo, hematol?gico e comprometimento neurol?gico no tipo II e III. H? tr?s enzimas recombinantes para a terapia de reposi??o enzim?tica na doen?a de Gaucher: Velaglucerase alfa, Alfataliglucerase e Imiglucerase que diferem entre si principalmente em rela??o ? forma de produ??o, ? sequ?ncia de amino?cidos e ao padr?o de glicosila??o. Atualmente, a terapia de reposi??o enzim?tica ? administrada por um medicamento chamado Cerezyme? (imiglucerase), produzido atrav?s da tecnologia do DNA recombinante utilizando culturas de c?lulas obtidas do ov?rio de hamster chin?s. A imiglucerase difere da glucocerebrosidase natural, de origem placent?ria, por um amino?cido na posi??o 495, onde a histidina ? substitu?da por arginina. Entretanto, o custo do medicamento dispon?vel ? muito alto, dificultando o acesso ? terapia. No Brasil, h? aproximadamente 600 portadores da doen?a e o tratamento ? garantido por lei a todos os pacientes, embora os gastos com a compra do medicamento sejam muito elevados. Este custo poderia ser consideravelmente reduzido se a enzima pudesse ser produzida de forma alternativa. Estudos demonstraram que t?cnicas reprodutivas avan?adas permitem que animais transg?nicos possam ser usados como biorreatores para a produ??o de prote?nas recombinantes de elevado potencial biol?gico e interesse farmac?utico. O Laborat?rio de Biologia Molecular e do Desenvolvimento da Universidade de Fortaleza em parceria com a Quatro G Pesquisa e Desenvolvimento desenvolveu o primeiro clone transg?nico de cabras da Am?rica Latina cuja gl?ndula mam?ria ? usada como um biorreator para a produ??o da prote?na glucocerebrosidase humana recombinante. Neste presente estudo, foi apresentado uma alternativa de purifica??o da enzima glucocerebrosidase a partir do leite obtido atrav?s da lacta??o induzida da cabra transg?nica e clonada. De acordo com os resultados, pode-se criar uma expectativa positiva para a obten??o da glucocerebrosidase atrav?s do procedimento citado ao longo deste estudo. A confirma??o da presen?a de atividade enzim?tica de glucocerebrosidase foi realizada pelo ensaio fluorim?trico, Cerezyme? e leite da cabra controle (n?o transg?nica) foram usados com controle positivo e negativo, respectivamente. O objetivo deste estudo foi estabelecer protocolos de purifica??o da enzima glucocerebrosidase a partir do leite da cabra clonada e transg?nica e confirmar a atividade enzim?tica, avaliar a express?o da enzima por eletroforese e caracterizar a prote?na recombinante atrav?s da espectrometria de massa.
66

Μελέτη της γονιδιακής μεταφοράς του γονιδίου της γλυκοκερεβροσιδάσης με ιικά οχήματα σε προγονικά αιμοποιητικά κύτταρα του ανθρώπου / Study of the glucocerebrosidase gene transfer with viral vectors into human hematopoietic progenitor cells

Πολυβίου, Σταύρος 04 December 2012 (has links)
Η ποσοτική ή ποιοτική ανεπάρκεια του λυσοσωματικού ενζύμου γλυκοκερεβροσιδάση οδηγεί στην παθολογία της νόσου Gaucher με κεντρικό το ρόλο της συσσώρευσης του υποστρώματός της, του γλυκοκερεβροσιδίου, στα μακροφάγα. Για περισσότερες από δύο δεκαετίες χρησιμοποιούνται γ-ρετροϊικά οχήματα στην ερευνητική προσέγγιση της διόρθωσης του ελλείμματος μέσω γονιδιακής μεταφοράς του γονιδίου της γλυκοκερεβροσιδάσης. Όπως έχει αναδειχθεί και σε κλινικό επίπεδο, είναι επιτακτική η ανάγκη για το σχεδιασμό γ ρετροϊικών οχημάτων, τα οποία θα είναι όχι μόνο αποτελεσματικά αλλά και ασφαλή, με κύριο στόχο τον περιορισμό της πιθανότητας εξαλλαγής του κυττάρου από τις συνέπειες της ενσωμάτωσης («μεταλλαξιγένεση κατά την ενσωμάτωση»). Η παρούσα μελέτη έχει ως στόχο τον έλεγχο της αποτελεσματικότητας νέων και θεωρητικά ασφαλέστερων σε σχέση με προηγουμένως χρησιμοποιηθέντα σε προκλινικό και κλινικό επίπεδο γ-ρετροϊικών οχημάτων για τη γονιδιακή μεταφορά του γονιδίου της γλυκοκερεβροσιδάσης σε προγονικά αιμοποιητικά κύτταρα του ανθρώπου. Στο πρώτο μέρος παρουσιάζεται η μελέτη έξι νέων και θεωρητικά ασφαλέστερων γ ρετροϊικών οχημάτων με το γονίδιο της γλυκοκερεβροσιδάσης, τα οποία είναι Self Inactivating (SIN) οχήματα και φέρουν αλληλουχίες για τη βελτίωση της ολοκλήρωσης της μεταγραφής, είτε από τον ιό WHV (WPRE, Woodchuck hepatitis virus Post-transcriptional Regulatory Element) είτε από τον ιό SV40 (2xSV40 USE, Simian Virus 40 Upstream Sequence Element σε δύο διαδοχικά αντίγραφα). Καταδεικνύεται ότι αυτά τα νέα SIN γ ρετροϊικά οχήματα είναι ικανά να μεταφέρουν ένα ενεργό φυσιολογικό γονίδιο γλυκοκερεβροσιδάσης σε CD34+ ανθρώπινο πρωτογενή προγονικό αιμοποιητικό κυτταρικό πληθυσμό. Τα οχήματα αυτά εμφάνισαν διαφορές στην αύξηση της ενζυμικής δραστικότητας, που προέκυψε από τη διαγονιδιακή έκφραση, οι οποίες οφείλονταν εν μέρει σε διαφορές στην αποδοτικότητα της διαμόλυνσης. Το δεύτερο μέρος της μελέτης περιλαμβάνει τέσσερα νέα SIN γ-ρετροϊικά οχήματα με το γονίδιο της γλυκοκερεβροσιδάσης με αντίστοιχο αριθμό οχημάτων-μαρτύρων, τα οποία είναι σχεδιασμένα με στόχο την κυτταροειδική έκφραση στα μονοκύτταρα / μακροφάγα, ώστε να περιοριστούν οι κυτταρικοί πληθυσμοί που εκτίθενται στην πιθανότητα ενεργοποίησης πρωτογκογονιδίων από τη δραστικότητα ενός εσωτερικού υποκινητή. Τα οχήματα φέρουν τους υποκινητές των ανθρώπινων γονιδίων CD11b και CD68 σε αλληλουχίες που είχαν επιδείξει στο παρελθόν μυελοειδοειδική έκφραση σε πειράματα γονιδιακής μεταφοράς. Τα νέα αυτά οχήματα ελέγχθηκαν ως προς την ικανότητά τους να παρουσιάζουν ισχυρότερη έκφραση του διαγονιδίου μετά από μονοκυτταρική / μακροφαγική διαφοροποίηση διαμολυσμένου CD34+ ανθρώπινου πρωτογενή προγονικού αιμοποιητικού κυτταρικού πληθυσμού σε σχέση με την έκφραση σε ένα λιγότερο διαφοροποιημένο διαμολυσμένο κυτταρικό πληθυσμό. Τα αποτελέσματα του δεύτερου μέρος της μελέτης σε συνδυασμό με τα ήδη υπάρχοντα βιβλιογραφικά δεδομένα ενθαρρύνουν την περαιτέρω διερεύνηση του υποκινητή του CD68 στο πλαίσιο των προσπαθειών για μυελοειδοειδική γονιδιακή μεταφορά του γονιδίου της γλυκοκερεβροσιδάσης, χωρίς να ενθαρρύνουν την περαιτέρω διερεύνηση του υποκινητή του CD11b. / Quantitative or qualitative deficiency of the lysosomal enzyme glucocerebrosidase results in the accumulation of its substrate, glucocerebroside, in macrophages, leading to the pathology of Gaucher disease. For more than two decades of research, gammaretroviral vectors have been used for gene transfer of the glucocerebrosidase gene for the correction of the enzyme’s deficit. It has been shown, even on clinical level, that the design of efficient as well as safe gammaretroviral vectors, aiming mainly at eliminating “insertional mutagenesis”, is an imperative need. The present study aims at the determination of the efficiency of new and theoretically safer, gammaretroviral vectors, compared to previously used ones on preclinical and clinical level, for the gene transfer of the glucocerebrosidase gene into human hematopoietic progenitor cells. In the first part of the study, six new and theoretically safer gammaretroviral vectors of the glucocerebrosidase gene have been evaluated. All six vectors are Self-Inactivating (SIN) and bear sequences for the improvement of transcriptional termination. These are either the WPRE (“Woodchuck hepatitis virus Post-transcriptional Regulatory Element”) from the virus WHV or the 2xSV40 USE (two copies of “Simian Virus 40 Upstream Sequence Element” in tandem repeat) from the virus SV40. It is shown that these new gammaretroviral vectors are efficient in transferring an active wild type glucocerebrosidase gene copy into a CD34+ human primary hematopoietic progenitor cell population. All six vectors showed increased enzyme activity, as compared to the untransduced cells, albeit with differences amongst them, partly due to differences in the transduction efficiency. The second part of the study focuses on the analysis of four new SIN gammaretroviral vectors of the glucocerebrosidase gene and the corresponding number of control vectors, designed for cell-specific expression in monocytes / macrophages. The aim is to thus limit the range of cell populations to be exposed to possible proto-oncogene activation from the internal promoter activity. In these vectors the expression of a glucocerebrosidase gene is driven by one of the promoters of the human genes for CD11b and CD68, which have exhibited myeloid specific expression in gene transfer experiments in the past. These new vectors were studied for their effectiveness in leading to stronger transgene expression after monocytic / macrophagic differentiation of a transduced CD34+ human primary hematopoietic progenitor cell population, compared to a less differentiated transduced cell population. The results of this study, taken together with the current bibliographical data, are encouraging for further study mainly of the CD68 promoter in the context of the research approach to myeloid specific gene transfer of the glucocerebrosidase gene.
67

Investigação da capacidade antioxidante, perfil inflamatório e dano ao DNA em pacientes com Doença de Gaucher tratados com a terapia de reposição enzimática

Turcatel, Elias January 2015 (has links)
A doença de Gaucher (DG) é uma doença de armazenamento lisossômico causada por uma mutação no gene que codifica a enzima β-glicosidase, a deficiência dessa enzima provoca o acúmulo de glicosilceramidas nos lisossomos do sistema retículo endotelial. A DG é divididas em três tipos, o tipo I é a forma mais branda e mais prevalente da doença. As consequências desta doença incluem hepatoesplenomegalia, deficiências ósseas, manifestações hematológicas e neurodegeneração, porém os mecanismos fisiopatológicos ainda não estão totalmente esclarecidos. Portanto, a fim de esclarecer a fisiopatologia envolvida na DG, o presente estudo avaliou a produção de espécies reativas de oxigênio, as atividades da superóxido dismutase, catalase e glutationa peroxidase, os níveis de nitritos, os imunoconteúdos de iNOS e de pNF-kB, os danos ao DNA e o conteúdo sulfidrilas em diferentes componentes da sangue de indivíduos afetados. Os pacientes foram divididos em dois grupos: controles com diagnóstico negativo para DG e pacientes diagnosticados com DG tipo I, tratados com terapia de reposição enzimática. O sangue foi coletado 5 minutos antes do tratamento. Os resultados mostraram que a atividade de superóxido dismutase foi reduzida em eritrócitos, enquanto atividade da glutationa peroxidase foi aumentada no plasma de pacientes com DG. Os níveis de nitritos e o imunoconteúdo pNF-kB estavam significativamente aumentados no plasma e leucócitos, respectivamente. Ensaio do cometa foi realizada no sangue total e indicou danos no DNA. Observou-se também um dano oxidativo a proteínas, devido a redução do conteúdo sulfidrilas em plasma e eritrócitos. Nossos resultados sugerem que pacientes com DG, mesmo em tratamento, apresentam alteração no status oxidativo/nitrativo e parâmetros inflamatórios, bem como evidências de danos ao DNA no sangue, o que poderia ser, pelo menos em parte, associado à fisiopatologia da DG. / Gaucher disease (GD) is a lysosomal storage disorder caused by a mutation in the gene encoding β-glucosidase enzyme, this enzyme deficiency leads to glucosylceramides accumulation in the lysosomes of the reticulum endothelial system. GD divided into three types, where in type I is the mildest and most prevalent form of disease. The consequences of this disease include hepatosplenomegaly, bone impairments, hematologic manifestations and neurodegeneration, but pathophysiology mechanisms are still not well elucidated. Therefore, in order to clarify the pathophysiology involved in GD, the present study evaluated reactive oxygen species production, superoxide dismutase, catalase and gluthatione peroxidase activities, nitrite levels, immunocontent of iNOS and pNF-κB, DNA damage and sulfhydryl content in differents components of blood from affected individuals.Patients were divided into two groups: controls with negative diagnosis to GD and patients diagnosed to GD type I treated with enzyme replacement therapy. Blood were collected 5 minutes before the treatment. Results showed that superoxide dismutase activity was reduced in erythrocytes while gluthatione peroxidase activity was increased in plasma of GD patients. Nitrite levels and pNF-κB immunocontent were significantly increased in plasma and leukocytes, respectively. Comet assay was performed in whole blood and indicated DNA damage. We also observed an oxidative damage to proteins elicited by decreased sulfhydryl content in plasma and erythrocytes. Our findings suggest that patients with GD, even in treatment, have altered oxidative/nitrative status and inflammatory parameters, as well as evidence of DNA damage in blood, what could be at least in part, associated with pathophysiology of GD.
68

Implementação e padronização de técnicas de dosagem enzimática para detecção de doenças de depósito lisossômico / Implementation and standardization of enzymatic activity techniques for lysosomal storage disease diagnosis

Müller, Karen Barbosa [UNIFESP] 27 February 2009 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-27 / Objetivo: Implementar e padronizar técnicas de dosagem de atividade enzimática em gota seca de sangue em papel de filtro para as seguintes enzimas lisossomais: - galactosidase A, que permite diagnosticar pacientes com Doença de Fabry, - iduronidase, que permite identificar pacientes com Mucopolissacaridose tipo I; - glicosidase e quitotriosidase, que permitem diagnosticar pacientes com Doença de Gaucher e -glicosidase, que permite identificar pacientes com Doença de Pompe, além da enzima -galactosidase, que possibilita avaliar a qualidade do material. Determinar o valor de corte para todas estas enzimas, que irá possibilitar a diferenciação dos indivíduos saudáveis dos pacientes. Metodologia: Ao todo foram selecionados 302 indivíduos, de ambos os sexos e com idades entre 18 e 82 anos. Foram coletados de 5 a 10 mL de sangue periférico de cada voluntário, e posteriormente 4 ou 5 gotas de sangue foram transferidas com o auxílio de uma pipeta tipo Pasteur para um papel de filtro. Todas as técnicas de dosagem de atividade enzimática realizadas neste trabalho baseiam-se na ação da enzima de interesse sobre um substrato sintético específico, que libera após clivagem uma molécula que emite fluorescência. A atividade enzimática será proporcional à quantidade de fluorescência detectada pelo equipamento. Resultados: Com as dosagens de atividade enzimática realizadas neste trabalho foram obtidos os seguintes resultados (média±desvio-padrão; valores mínimos e máximos), expressos em μmol/L/h: -galactosidase (14,09±4,36; 4,04-29,65); -galactosidase A (4,57±1,37; 1,44-10,67); -iduronidase (3,45±1,21; 1,40-7,78); -glicosidase (4,57±1,37; 1,44-10,67); quitotriosidase (12,88±9,84; 0,00- 48,07); -glicosidase (5,41±1,74; 2,10-10,65); também expressa pela razão - glicosidase neutra/ -glicosidase ácida inibida (13,19±4,26; 5,03-28,58); e pela por cento inibição da -glicosidase ácida (70,66±7,60; 36,38-87,08). Os cálculos de sensibilidade e especificidade, realizados confrontando a técnica que utiliza papel de filtro com a técnica que utiliza leucócitos, resultaram em valores acima de 50 por cento, que são considerados adequados. Conclusões: As análises estatísticas dos resultados obtidos possibilitaram a escolha do valor de corte mais preciso, o que permite a diferenciação entre indivíduos saudáveis e pacientes com Doença de Fabry, Doença de Pompe, Doença de Gaucher e Mucopolissacaridose tipo I. Os valores de atividade enzimática observados se mostraram de acordo com os descritos na literatura, com pequenas variações. As técnicas de diagnóstico que utilizam papel de filtro podem ser consideradas uma ferramenta eficiente, barata e simples de serem realizadas. Objetivo: Implementar e padronizar técnicas de dosagem de atividade enzimática em gota seca de sangue em papel de filtro para as seguintes enzimas lisossomais: - galactosidase A, que permite diagnosticar pacientes com Doença de Fabry, - iduronidase, que permite identificar pacientes com Mucopolissacaridose tipo I; - glicosidase e quitotriosidase, que permitem diagnosticar pacientes com Doença de Gaucher e -glicosidase, que permite identificar pacientes com Doença de Pompe, além da enzima -galactosidase, que possibilita avaliar a qualidade do material. Determinar o valor de corte para todas estas enzimas, que irá possibilitar a diferenciação dos indivíduos saudáveis dos pacientes. Metodologia: Ao todo foram selecionados 302 indivíduos, de ambos os sexos e com idades entre 18 e 82 anos. Foram coletados de 5 a 10 mL de sangue periférico de cada voluntário, e posteriormente 4 ou 5 gotas de sangue foram transferidas com o auxílio de uma pipeta tipo Pasteur para um papel de filtro. Todas as técnicas de dosagem de atividade enzimática realizadas neste trabalho baseiam-se na ação da enzima de interesse sobre um substrato sintético específico, que libera após clivagem uma molécula que emite fluorescência. A atividade enzimática será proporcional à quantidade de fluorescência detectada pelo equipamento. Resultados: Com as dosagens de atividade enzimática realizadas neste trabalho foram obtidos os seguintes resultados (média±desvio-padrão; valores mínimos e máximos), expressos em μmol/L/h: -galactosidase (14,09±4,36; 4,04-29,65); -galactosidase A (4,57±1,37; 1,44-10,67); -iduronidase (3,45±1,21; 1,40-7,78); -glicosidase (4,57±1,37; 1,44-10,67); quitotriosidase (12,88±9,84; 0,00- 48,07); -glicosidase (5,41±1,74; 2,10-10,65); também expressa pela razão - glicosidase neutra/ -glicosidase ácida inibida (13,19±4,26; 5,03-28,58); e pela por cento inibição da -glicosidase ácida (70,66±7,60; 36,38-87,08). Os cálculos de sensibilidade e especificidade, realizados confrontando a técnica que utiliza papel de filtro com a técnica que utiliza leucócitos, resultaram em valores acima de 50 por cento, que são considerados adequados. Conclusões: As análises estatísticas dos resultados obtidos possibilitaram a escolha do valor de corte mais preciso, o que permite a diferenciação entre indivíduos saudáveis e pacientes com Doença de Fabry, Doença de Pompe, Doença de Gaucher e Mucopolissacaridose tipo I. Os valores de atividade enzimática observados se mostraram de acordo com os descritos na literatura, com pequenas variações. As técnicas de diagnóstico que utilizam papel de filtro podem ser consideradas uma ferramenta eficiente, barata e simples de serem realizadas. / Objectives: To implement and to standardize enzymatic activity techniques using dried blood spots on filter paper for the enzymes -galactosidase A, for the diagnosis of Fabry Disease patients; -iduronidase, for the diagnosis of Mucopolysaccharidosis type I patients; -glucosidase and chitotriosidase, for the diagnosis of Gaucher Disease patients and acid -glucosidase, that allows the diagnosis of Pompe Disease patients; besides the enzyme -galactosidase, that allows assessing the quality of the material. In addition, to determine the cut-off value for each enzyme, that will enable the discrimination between healthy subjects and patients. Methodology: 302 volunteers of both gender were selected, with ages between 18 and 82 years old. Peripheral blood was collected in heparin containing tubes and blood spots were prepared according to the protocol. All enzymatic activity techniques carried out in this work were based in the cleavage of a specific synthetic substrate, by the action of target enzymes which then releases a fluorescent molecule that will be detected by the fluorimeter. Results: The values of enzyme activity obtained in this work were the following (mean±standard deviation; minimum and maximum values), expressed in μmol/L/h: -galactosidase (14,09±4,36; 4,04-29,65); -galactosidase A (4,57±1,37; 1,44-10,67); -iduronidase (3,45±1,21; 1,40-7,78); -glucosidase (4,57±1,37; 1,44-10,67); chitotriosidase (12,88±9,84; 0,00-48,07); -glucosidase (5,41±1,74; 2,10-10,65); also expressed in the ratio of neutral -glucosidase/inhibited acid -glucosidase (13,19±4,26; 5,03-28,58); and as % of acid -glucosidase inhibition (70,66±7,60; 36,38-87,08). The sensibility and specificity values obtained with the comparison of leukocytes and dried blood spots results showed that all techniques are reliable and appropriate. Conclusions: The results from this work enabled us to choose the most accurate cut-off values which to distinguish between healthy subjects and patients with Fabry Disease, Mucopolysaccharidosis type I, Gaucher Disease and Pompe Disease. Enzyme activity values are in agreement with the literature data. The use of dried blood spots for lysosomal disease diagnosis can be considered efficient, inexpensive and simple to be performed. / TEDE / BV UNIFESP: Teses e dissertações
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Investigação da capacidade antioxidante, perfil inflamatório e dano ao DNA em pacientes com Doença de Gaucher tratados com a terapia de reposição enzimática

Turcatel, Elias January 2015 (has links)
A doença de Gaucher (DG) é uma doença de armazenamento lisossômico causada por uma mutação no gene que codifica a enzima β-glicosidase, a deficiência dessa enzima provoca o acúmulo de glicosilceramidas nos lisossomos do sistema retículo endotelial. A DG é divididas em três tipos, o tipo I é a forma mais branda e mais prevalente da doença. As consequências desta doença incluem hepatoesplenomegalia, deficiências ósseas, manifestações hematológicas e neurodegeneração, porém os mecanismos fisiopatológicos ainda não estão totalmente esclarecidos. Portanto, a fim de esclarecer a fisiopatologia envolvida na DG, o presente estudo avaliou a produção de espécies reativas de oxigênio, as atividades da superóxido dismutase, catalase e glutationa peroxidase, os níveis de nitritos, os imunoconteúdos de iNOS e de pNF-kB, os danos ao DNA e o conteúdo sulfidrilas em diferentes componentes da sangue de indivíduos afetados. Os pacientes foram divididos em dois grupos: controles com diagnóstico negativo para DG e pacientes diagnosticados com DG tipo I, tratados com terapia de reposição enzimática. O sangue foi coletado 5 minutos antes do tratamento. Os resultados mostraram que a atividade de superóxido dismutase foi reduzida em eritrócitos, enquanto atividade da glutationa peroxidase foi aumentada no plasma de pacientes com DG. Os níveis de nitritos e o imunoconteúdo pNF-kB estavam significativamente aumentados no plasma e leucócitos, respectivamente. Ensaio do cometa foi realizada no sangue total e indicou danos no DNA. Observou-se também um dano oxidativo a proteínas, devido a redução do conteúdo sulfidrilas em plasma e eritrócitos. Nossos resultados sugerem que pacientes com DG, mesmo em tratamento, apresentam alteração no status oxidativo/nitrativo e parâmetros inflamatórios, bem como evidências de danos ao DNA no sangue, o que poderia ser, pelo menos em parte, associado à fisiopatologia da DG. / Gaucher disease (GD) is a lysosomal storage disorder caused by a mutation in the gene encoding β-glucosidase enzyme, this enzyme deficiency leads to glucosylceramides accumulation in the lysosomes of the reticulum endothelial system. GD divided into three types, where in type I is the mildest and most prevalent form of disease. The consequences of this disease include hepatosplenomegaly, bone impairments, hematologic manifestations and neurodegeneration, but pathophysiology mechanisms are still not well elucidated. Therefore, in order to clarify the pathophysiology involved in GD, the present study evaluated reactive oxygen species production, superoxide dismutase, catalase and gluthatione peroxidase activities, nitrite levels, immunocontent of iNOS and pNF-κB, DNA damage and sulfhydryl content in differents components of blood from affected individuals.Patients were divided into two groups: controls with negative diagnosis to GD and patients diagnosed to GD type I treated with enzyme replacement therapy. Blood were collected 5 minutes before the treatment. Results showed that superoxide dismutase activity was reduced in erythrocytes while gluthatione peroxidase activity was increased in plasma of GD patients. Nitrite levels and pNF-κB immunocontent were significantly increased in plasma and leukocytes, respectively. Comet assay was performed in whole blood and indicated DNA damage. We also observed an oxidative damage to proteins elicited by decreased sulfhydryl content in plasma and erythrocytes. Our findings suggest that patients with GD, even in treatment, have altered oxidative/nitrative status and inflammatory parameters, as well as evidence of DNA damage in blood, what could be at least in part, associated with pathophysiology of GD.
70

Investigação da capacidade antioxidante, perfil inflamatório e dano ao DNA em pacientes com Doença de Gaucher tratados com a terapia de reposição enzimática

Turcatel, Elias January 2015 (has links)
A doença de Gaucher (DG) é uma doença de armazenamento lisossômico causada por uma mutação no gene que codifica a enzima β-glicosidase, a deficiência dessa enzima provoca o acúmulo de glicosilceramidas nos lisossomos do sistema retículo endotelial. A DG é divididas em três tipos, o tipo I é a forma mais branda e mais prevalente da doença. As consequências desta doença incluem hepatoesplenomegalia, deficiências ósseas, manifestações hematológicas e neurodegeneração, porém os mecanismos fisiopatológicos ainda não estão totalmente esclarecidos. Portanto, a fim de esclarecer a fisiopatologia envolvida na DG, o presente estudo avaliou a produção de espécies reativas de oxigênio, as atividades da superóxido dismutase, catalase e glutationa peroxidase, os níveis de nitritos, os imunoconteúdos de iNOS e de pNF-kB, os danos ao DNA e o conteúdo sulfidrilas em diferentes componentes da sangue de indivíduos afetados. Os pacientes foram divididos em dois grupos: controles com diagnóstico negativo para DG e pacientes diagnosticados com DG tipo I, tratados com terapia de reposição enzimática. O sangue foi coletado 5 minutos antes do tratamento. Os resultados mostraram que a atividade de superóxido dismutase foi reduzida em eritrócitos, enquanto atividade da glutationa peroxidase foi aumentada no plasma de pacientes com DG. Os níveis de nitritos e o imunoconteúdo pNF-kB estavam significativamente aumentados no plasma e leucócitos, respectivamente. Ensaio do cometa foi realizada no sangue total e indicou danos no DNA. Observou-se também um dano oxidativo a proteínas, devido a redução do conteúdo sulfidrilas em plasma e eritrócitos. Nossos resultados sugerem que pacientes com DG, mesmo em tratamento, apresentam alteração no status oxidativo/nitrativo e parâmetros inflamatórios, bem como evidências de danos ao DNA no sangue, o que poderia ser, pelo menos em parte, associado à fisiopatologia da DG. / Gaucher disease (GD) is a lysosomal storage disorder caused by a mutation in the gene encoding β-glucosidase enzyme, this enzyme deficiency leads to glucosylceramides accumulation in the lysosomes of the reticulum endothelial system. GD divided into three types, where in type I is the mildest and most prevalent form of disease. The consequences of this disease include hepatosplenomegaly, bone impairments, hematologic manifestations and neurodegeneration, but pathophysiology mechanisms are still not well elucidated. Therefore, in order to clarify the pathophysiology involved in GD, the present study evaluated reactive oxygen species production, superoxide dismutase, catalase and gluthatione peroxidase activities, nitrite levels, immunocontent of iNOS and pNF-κB, DNA damage and sulfhydryl content in differents components of blood from affected individuals.Patients were divided into two groups: controls with negative diagnosis to GD and patients diagnosed to GD type I treated with enzyme replacement therapy. Blood were collected 5 minutes before the treatment. Results showed that superoxide dismutase activity was reduced in erythrocytes while gluthatione peroxidase activity was increased in plasma of GD patients. Nitrite levels and pNF-κB immunocontent were significantly increased in plasma and leukocytes, respectively. Comet assay was performed in whole blood and indicated DNA damage. We also observed an oxidative damage to proteins elicited by decreased sulfhydryl content in plasma and erythrocytes. Our findings suggest that patients with GD, even in treatment, have altered oxidative/nitrative status and inflammatory parameters, as well as evidence of DNA damage in blood, what could be at least in part, associated with pathophysiology of GD.

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