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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.
11

Estudo sobre as manifestações gastrointestinais em pacientes com mucopolissacaridoses

Giugliani, Luciana January 2013 (has links)
Introdução: As Mucopolissacaridoses (MPS) são doenças lisossômicas causadas pela deficiência de enzimas envolvidas na degradação dos glicoaminoglicanos. O acúmulo anormal dessa molécula compromete a função celular e orgânica, levando a um espectro de manifestações clínicas, de caráter multissistêmico e progressivo. Manifestações gastrointestinais, tais como episódios frequentes de fezes amolecidas e diarréia, têm sido frequentemente evidenciadas e relatadas por pacientes com MPS. Ainda que os sintomas gastrointestinais sejam frequentemente ofuscados pelos fenótipos neurológicos graves, eles podem afetar a qualidade de vida dos pacientes e de seus familiares. Objetivo: Avaliar as manifestações gastrointestinais em pacientes com MPS que estavam ou não recebendo Terapia de Reposição Enzimática (TRE). Adicionalmente, para melhor compreender o assunto, avaliamos a histologia da mucosa intestinal em camundongos com MPS I. Métodos: Estudo transversal com amostragem de conveniência. Foram incluídos no estudo pacientes com diagnóstico de qualquer tipo de MPS que estavam ou não em TRE. Os sujeitos foram avaliados através de inquérito alimentar, questionamentos quanto ao aparecimento de sintomas gastrointestinais e realização de uma série de exames bioquímicos. Adicionalmente, foram realizados testes de bioimpedância elétrica (para avaliação da composição corporal) e teste molecular para hipolactasia primária a partir de amostras de DNA dos pacientes, assim como análise da histologia da mucosa intestinal em um modelo de camundongo com MPS I. Resultados: Foram incluídos 27 pacientes com diferentes tipos de MPS, sendo 15 (55,6%) do sexo feminino e 12 (44,4%) do sexo masculino, com mediana de idade de 12 (1-28) anos. Os sintomas gastrointestinais mais prevalentes foram flatulência, distensão abdominal, dor abdominal e fezes amolecidas. Houve diferença significativa na prevalência de flatulência entre os tipos de MPS (p=0,004). A prevalência de flatulência e de distensão abdominal foi significativamente maior no grupo dos que não recebiam TRE, em comparação ao grupo dos que recebia TRE (p = 0,04 e 0,03, respectivamente). A maioria dos exames bioquímicos realizados para investigação e/ou exclusão de alguma patologia específica apresentaram resultados normais, sugerindo que o aparecimento de sintomas gastrointestinais nesses pacientes possa ser decorrente da própria MPS através de mecanismo fisiopatológico independente. A análise da histologia do intestino delgado de camundongos MPS I identificou células aumentadas de volume, sugerindo algum tipo de acúmulo intracelular. Em relação ao Teste Molecular para Hipolactasia, 58,8% dos pacientes apresentaram genótipo CC, o qual é compatível com intolerância à lactose. Os exames de Bioimpedância Elétrica sugerem que, os pacientes em TRE apresentam menor proporção de massa gorda (MG) em relação aos pacientes que não estavam em TRE. Conclusão: Este foi o primeiro estudo sobre manifestações gastrointestinais de pacientes brasileiros com MPS realizado em nosso meio. Inúmeros sinais e sintomas foram observados, com maior prevalência relativa nas MPS I, II, III e IV do que na MPS VI. O sintoma mais frequentemente relatado foi flatulência. Embora não tenha sido estatisticamente significativo a diferença, a proporção de pacientes com sintomas gastrointestinais foi menor nos pacientes que estavam em TRE. A Intolerância à lactose observada em maior proporção nos pacientes com MPS com manifestações gastrointestinais, a avaliação da composição corporal e as alterações observadas na mucosa intestinal do camundongo com MPS I devem ser levadas em consideração na interpretação dos resultados. Acreditamos que mais estudos, dirigidos para as manifestações gastrointestinais, devam ser realizados para comprovar esses achados e melhor compreender os mecanismos fisiopatológicos dos sintomas relacionados nos pacientes aferidos. / Introduction: The mucopolysaccharidoses (MPS) are lysosomal storage disorders characterized by a deficiency in enzymes involved in glycosaminoglycan degradation. Abnormal accumulation of this molecule compromises cellular and organic function, leading to a spectrum of progressive, multisystem clinical manifestations. Gastrointestinal manifestations, such as frequent episodes of loose stools and diarrhea, are often reported by patients with MPS. Although these gastrointestinal symptoms are often overshadowed by severe neurological phenotypes, they can have a negative impact on the quality of life of patients and their family members. Objective: To assess gastrointestinal manifestations in patients with MPS who were or not receiving enzyme replacement therapy (ERT). Furthermore, we sought to assess bowel mucosa histology in a mouse model of MPS I. Methods: Cross-sectional study with a convenience sampling strategy. The sample comprised patients with a diagnosis of MPS of any type and regardless of ERT status. Patients were assessed by means of a dietary recordatory and an interview focused on gastrointestinal symptoms, as well as a battery of biochemical tests. Bioelectrical Impedance was performed for body composition assessment.Patient DNA samples were also tested by molecular tests for primary lactase hypolactasia, and bowel mucosa specimens from MPS I mice underwent histological examination. Results: A total of 27 MPS patients were included, 15 (55.6%) female and 12 (44.4%) male, with a median age of 12 (1-28) years. The most prevalent gastrointestinal symptoms were flatulence, abdominal distension, abdominal pain, and loose stools. A significant difference in the prevalence of flatulence was observed among different MPS types (p=0.004). The prevalence of flatulence and abdominal distension was significantly higher in the non-ERT group than in the ERT group (p = 0.04 and 0.03 respectively). Most biochemical tests performed to work up and/or rule out specific conditions were within normal limits, which suggests that the development of gastrointestinal systems in these patients may be due to MPS itself through an independent pathophysiological mechanism. Histological analysis of smallbowel tissue from MPS I mice found increased cell volume indicative of some form of intracellular accumulation. On molecular testing for lactase deficiency, 58.8% of patients had the CC genotype, which is consistent with lactose intolerance. Bioelectrical Impedance analysis suggest that patients with TRE have lower proportion of fat mass (FM) compared to patients who were not on ERT. Conclusion: This was the first study to assess gastrointestinal manifestations in Brazilian patients with different MPS subtypes.Several signs and symptoms were observed with higher relative prevalence in MPS I, II, III and IV to that in MPS VI. The most frequently reported symptom was flatulence. Although was no statistical difference the proportion of patients with gastrointestinal symptoms was lower in patients on ERT.The lactose intolerance observed in a higher proportion of MPS patients with gastrointestinal manifestations, body composition assessment and observed changes in the bowel mucosa of MPS I mice should be taken into account when interpreting the results. Further studies focusing on the gastrointestinal manifestations of MPS are warranted to corroborate our findings and provide a better understanding of the pathophysiological mechanisms associated with these symptoms in affected patients.
12

Estudo sobre as manifestações gastrointestinais em pacientes com mucopolissacaridoses

Giugliani, Luciana January 2013 (has links)
Introdução: As Mucopolissacaridoses (MPS) são doenças lisossômicas causadas pela deficiência de enzimas envolvidas na degradação dos glicoaminoglicanos. O acúmulo anormal dessa molécula compromete a função celular e orgânica, levando a um espectro de manifestações clínicas, de caráter multissistêmico e progressivo. Manifestações gastrointestinais, tais como episódios frequentes de fezes amolecidas e diarréia, têm sido frequentemente evidenciadas e relatadas por pacientes com MPS. Ainda que os sintomas gastrointestinais sejam frequentemente ofuscados pelos fenótipos neurológicos graves, eles podem afetar a qualidade de vida dos pacientes e de seus familiares. Objetivo: Avaliar as manifestações gastrointestinais em pacientes com MPS que estavam ou não recebendo Terapia de Reposição Enzimática (TRE). Adicionalmente, para melhor compreender o assunto, avaliamos a histologia da mucosa intestinal em camundongos com MPS I. Métodos: Estudo transversal com amostragem de conveniência. Foram incluídos no estudo pacientes com diagnóstico de qualquer tipo de MPS que estavam ou não em TRE. Os sujeitos foram avaliados através de inquérito alimentar, questionamentos quanto ao aparecimento de sintomas gastrointestinais e realização de uma série de exames bioquímicos. Adicionalmente, foram realizados testes de bioimpedância elétrica (para avaliação da composição corporal) e teste molecular para hipolactasia primária a partir de amostras de DNA dos pacientes, assim como análise da histologia da mucosa intestinal em um modelo de camundongo com MPS I. Resultados: Foram incluídos 27 pacientes com diferentes tipos de MPS, sendo 15 (55,6%) do sexo feminino e 12 (44,4%) do sexo masculino, com mediana de idade de 12 (1-28) anos. Os sintomas gastrointestinais mais prevalentes foram flatulência, distensão abdominal, dor abdominal e fezes amolecidas. Houve diferença significativa na prevalência de flatulência entre os tipos de MPS (p=0,004). A prevalência de flatulência e de distensão abdominal foi significativamente maior no grupo dos que não recebiam TRE, em comparação ao grupo dos que recebia TRE (p = 0,04 e 0,03, respectivamente). A maioria dos exames bioquímicos realizados para investigação e/ou exclusão de alguma patologia específica apresentaram resultados normais, sugerindo que o aparecimento de sintomas gastrointestinais nesses pacientes possa ser decorrente da própria MPS através de mecanismo fisiopatológico independente. A análise da histologia do intestino delgado de camundongos MPS I identificou células aumentadas de volume, sugerindo algum tipo de acúmulo intracelular. Em relação ao Teste Molecular para Hipolactasia, 58,8% dos pacientes apresentaram genótipo CC, o qual é compatível com intolerância à lactose. Os exames de Bioimpedância Elétrica sugerem que, os pacientes em TRE apresentam menor proporção de massa gorda (MG) em relação aos pacientes que não estavam em TRE. Conclusão: Este foi o primeiro estudo sobre manifestações gastrointestinais de pacientes brasileiros com MPS realizado em nosso meio. Inúmeros sinais e sintomas foram observados, com maior prevalência relativa nas MPS I, II, III e IV do que na MPS VI. O sintoma mais frequentemente relatado foi flatulência. Embora não tenha sido estatisticamente significativo a diferença, a proporção de pacientes com sintomas gastrointestinais foi menor nos pacientes que estavam em TRE. A Intolerância à lactose observada em maior proporção nos pacientes com MPS com manifestações gastrointestinais, a avaliação da composição corporal e as alterações observadas na mucosa intestinal do camundongo com MPS I devem ser levadas em consideração na interpretação dos resultados. Acreditamos que mais estudos, dirigidos para as manifestações gastrointestinais, devam ser realizados para comprovar esses achados e melhor compreender os mecanismos fisiopatológicos dos sintomas relacionados nos pacientes aferidos. / Introduction: The mucopolysaccharidoses (MPS) are lysosomal storage disorders characterized by a deficiency in enzymes involved in glycosaminoglycan degradation. Abnormal accumulation of this molecule compromises cellular and organic function, leading to a spectrum of progressive, multisystem clinical manifestations. Gastrointestinal manifestations, such as frequent episodes of loose stools and diarrhea, are often reported by patients with MPS. Although these gastrointestinal symptoms are often overshadowed by severe neurological phenotypes, they can have a negative impact on the quality of life of patients and their family members. Objective: To assess gastrointestinal manifestations in patients with MPS who were or not receiving enzyme replacement therapy (ERT). Furthermore, we sought to assess bowel mucosa histology in a mouse model of MPS I. Methods: Cross-sectional study with a convenience sampling strategy. The sample comprised patients with a diagnosis of MPS of any type and regardless of ERT status. Patients were assessed by means of a dietary recordatory and an interview focused on gastrointestinal symptoms, as well as a battery of biochemical tests. Bioelectrical Impedance was performed for body composition assessment.Patient DNA samples were also tested by molecular tests for primary lactase hypolactasia, and bowel mucosa specimens from MPS I mice underwent histological examination. Results: A total of 27 MPS patients were included, 15 (55.6%) female and 12 (44.4%) male, with a median age of 12 (1-28) years. The most prevalent gastrointestinal symptoms were flatulence, abdominal distension, abdominal pain, and loose stools. A significant difference in the prevalence of flatulence was observed among different MPS types (p=0.004). The prevalence of flatulence and abdominal distension was significantly higher in the non-ERT group than in the ERT group (p = 0.04 and 0.03 respectively). Most biochemical tests performed to work up and/or rule out specific conditions were within normal limits, which suggests that the development of gastrointestinal systems in these patients may be due to MPS itself through an independent pathophysiological mechanism. Histological analysis of smallbowel tissue from MPS I mice found increased cell volume indicative of some form of intracellular accumulation. On molecular testing for lactase deficiency, 58.8% of patients had the CC genotype, which is consistent with lactose intolerance. Bioelectrical Impedance analysis suggest that patients with TRE have lower proportion of fat mass (FM) compared to patients who were not on ERT. Conclusion: This was the first study to assess gastrointestinal manifestations in Brazilian patients with different MPS subtypes.Several signs and symptoms were observed with higher relative prevalence in MPS I, II, III and IV to that in MPS VI. The most frequently reported symptom was flatulence. Although was no statistical difference the proportion of patients with gastrointestinal symptoms was lower in patients on ERT.The lactose intolerance observed in a higher proportion of MPS patients with gastrointestinal manifestations, body composition assessment and observed changes in the bowel mucosa of MPS I mice should be taken into account when interpreting the results. Further studies focusing on the gastrointestinal manifestations of MPS are warranted to corroborate our findings and provide a better understanding of the pathophysiological mechanisms associated with these symptoms in affected patients.
13

Purification of human recombinant Naglu from Sf9 cells and uptake studies with MPS IIIB fibroblasts

Ashmead, Rhea 15 July 2019 (has links)
Mucopolysaccharidosis IIIB (MPS IIIB) is a rare, metabolic disorder that results from a deficiency in the lysosomal hydrolase, α-N-acetylglucosaminidase (Naglu). Naglu is a housekeeping enzyme involved in the degradation pathway of heparan sulfate. A deficiency in active Naglu leads to an accumulation of heparan sulfate within the lysosome, initiating a pathological cascade within the cell. Patients with MPS IIIB experience progressive central nervous system degeneration and die within the first few decades of life. Presently, enzyme replacement therapy, which is a standard of care for other lysosomal storage disorders, is an ineffective treatment for MPS IIIB. This is due to impermeability of the blood-brain barrier (BBB) to exogenous recombinant enzymes. A promising approach to this therapeutic obstacle is protein transduction domains. Protein transduction domains have been shown to facilitate the delivery of active enzyme across the BBB in mice. Previously, our laboratory used Spodoptera frugiperda (Sf9) insect cell system to express human recombinant Naglu fused to a synthetic protein transduction domain (PTD4). The purpose was to use PTD4 to the facilitate the delivery of Naglu across biological membranes, including the blood-brain barrier. However, a missing stop codon following PTD4 limited its transducibility. The stop codon was re-introduced and the improved fusion enzyme, Naglu-PTD4X, was stably expressed in Sf9 cells. The overarching goal of this project is to create a large-scale production of human recombinant Naglu that has the potential to be used to treat the neuropathology of patients with MPS IIIB. This project used a three-step purification system to purify Naglu-PTD4X. Uptake of Naglu-PTD4X was assessed in MPS IIIB fibroblasts using a fluorogenic activity assay, immunoblotting, and immunocytochemistry. Our purification system was successful at purifying Naglu-PTD4X to homogeneity with a 26% yield and specific activity of 84,000 units/mg. An increase in Naglu activity was detected in MPS IIIB fibroblasts following incubation with Naglu-PTD4X. Future directions will focus on optimizing immunodetection and conducting BBB penetration studies in murine models. / Graduate / 2020-06-21
14

Avaliação do uso de amostras de leucócitos impregnados em papel filtro para o diagnóstico de doenças lisossômicas

Camelier, Marli Teresinha Viapiana January 2016 (has links)
Introdução: As Doenças lisossômicas (DLs) são condições genéticas, herdadas na sua maioria de forma autossômica recessiva, caracterizadas usualmente pela deficiência de enzimas lisossômicas específicas, envolvidas na síntese, degradação, armazenamento ou transporte de macromoléculas necessárias para o funcionamento normal do organismo. Nas situações mais típicas, o substrato não degradado acumula-se progressivamente nos lisossomos, com repercussões estruturais e funcionais, levando a sinais e sintomas característicos. Os pacientes apresentam um amplo espectro de manifestações clínicas, que podem incluir disfunção de órgãos, anormalidades esqueléticas, envolvimento neuronal, entre outras. O diagnóstico é usualmente obtido pela identificação da deficiência enzimática específica em leucócitos obtidos do sangue periférico, usualmente realizado em laboratórios de referência. O transporte da amostra pode ser um obstáculo quando o serviço requisitante está situado longe do centro de referência ou em outro país, situação em que a amostra de sangue pode chegar ao laboratório já sem condições de ser analisada. Objetivo: Este estudo teve como objetivo principal, tornar disponível um método mais simples, seguro e acessível que utiliza amostras de leucócitos impregnados em papel filtro (LIPF) como uma nova ferramenta para o diagnóstico bioquímico de pacientes com DLs. Métodos: O estudo envolveu amostras de pacientes com diagnóstico previamente confirmado de DLs (amostra de conveniência, por se tratarem de doenças raras, com incidências individuais ao redor de 1:100.000 recém-nascidos vivos). Foram incluídos no estudo os pacientes com diagnóstico já estabelecido de DLs selecionadas (MPS IVA, Doença de Krabbe, Doença de Gaucher e Doença de Pompe), independente do sexo e/ou idade, atendidos no Serviço de Genética Médica do HCPA, que concordaram em participar do estudo. O grupo de referência negativo foi constituído pelas amostras de 50 indivíduos hígidos, adultos, de ambos os sexos. Resultados: Os resultados obtidos nos ensaios enzimáticos de pacientes com MPS IVA, Doença de Krabbe, Doença de Gaucher e Doença de Pompe, indicaram que as enzimas analisadas em amostras de LIPF permitiram a identificação de todos os pacientes, com sensibilidade de 100%. Os testes de estabilidade realizados nas amostras de LIPF indicaram que as amostras, quando mantidas a 4ºC, se mostram estáveis por pelo menos 30 dias. Conclusões: Nas condições utilizadas, amostras de LIPF se mostraram adequadas para a identificação segura de pacientes com MPS tipo IVA, Doença de Krabbe, Doença de Gaucher e Doença de Pompe. As amostras de leucócitos secos em papel filtro são mais estáveis e seguras para o transporte, indicando que possa ser esta uma importante ferramenta para facilitar a identificação de pacientes com DLDs, especialmente daqueles que vivem em áreas que tem dificuldades para a remessa de amostras líquidas para serviços de referência. / Background: Lysosomal Disorders (LDs) are genetic conditions, mostly inherited in autosomal recessive fashion, usually characterized by a deficiency of specific lysosomal enzymes involved in the synthesis, degradation, storage or transportation of macromolecules necessary for normal functioning of the organism. Typically, the non-degraded substrate is progressively accumulated in lysosomes, with structural and functional repercussions, leading to characteristic signs and symptoms. Affected patients present a wide range of clinical manifestations, which may include organ dysfunction, skeletal anomalies, neuronal involvement, etc. The diagnosis is normally made through identification of the specific enzyme deficiency in white blood cells from a sample of peripheral blood, usually performed in reference laboratories. The transporting of a liquid sample can be a problem when the test orderer is located far from the reference center or in a foreign country, as often the blood sample arrives at the laboratory in poor condition and cannot be properly analyzed. Aim: The main aim of this study was to make available a new technique that is simpler, safer and more accessible, using leukocytes impregnated on filter paper (LIFP) as a new tool for the biochemical diagnosis of patients with LSDs. Methods: This study involved samples of patients with previously confirmed diagnosis of selected LSDs (a convenience sample, as these are rare diseases, with individual incidences around 1:100.000 live newborns). Patients with an established diagnosis of MPS IVA, Krabbe Disease, Gaucher’s disease and Pompe disease regardless of sex and/or age, cared for at the Genetics Service of HCPA and who agreed to participate were included in the study. The negative reference group comprised blood samples from 50 healthy adults of both genders. Results: The results obtained in the enzymatic assays of patients with MPS IVA, Krabbe Disease, Gaucher’s disease, and Pompe disease indicated that the analyzed enzymes in LIFP samples allowed the identification of all patients, with sensitivity of 100%. The stability tests performed in LIFP samples indicated that samples, when maintained at 4ºC, were stable for at least 30 days. Conclusions: In the conditions used, LIFP samples were shown to be adequate for a reliable identification of patients with MPS IVA, Krabbe Disease, Gaucher’s disease, and Pompe disease. Blood samples on filter paper are more stable and reliable for transportation, indicating that this may be an important tool to facilitate the identification of patients with LSDs, particularly those living in areas with difficulties for the shipment of liquid samples to reference cervices.
15

Expression variation in lysosomal storage disorder genes

Mason, Lyndel Ann January 2006 (has links)
Metachromatic leukodystrophy (MLD) and Gaucher disease (GD) are caused by a deficiency of arylsulphatase A (ASA) and b-glucocerebrosidase (GBA), respectively. They are lysosomal storage disorders with a heterogeneous clinical spectrum encompassing visceral, skeletal and neurologic involvement resulting in high morbidity and mortality. The overall aim of this study is to elucidate the genetic component/s of high ASA and GBA enzyme activity in normal healthy individuals with the ultimate goal of using this information to produce greater protein activity from a recombinant protein. A wide variation in ASA and GBA enzyme activity levels has been observed in the normal population. The first objective of this project was to identify and characterise single nucleotide polymorphisms (SNPs) in the arylsulphatase A (ARSA) and glucocerebrosidase (GBA) genes that are responsible for determining the levels of expressed enzyme activity in the normal population. The second objective was to assess the contribution of transcriptional regulation and TCP80 mediated translational control to normal enzyme variation. TCP80, a translational control protein that interacts with the GBA coding region, is a splice variant of the interleukin binding factor 3 (ILF3) gene. Ten samples from individuals with high ASA activity and twenty samples from individuals with high GBA activity were screened for polymorphisms via denaturing high pressure liquid chromatography (dHPLC) and sequencing. The frequency of these polymorphisms in the normal population was determined using dot-blot hybridisation. Fifteen ARSA polymorphisms (4 promoter, 5 coding, 5 intronic and 1 poly(A) signal) and two GBA polymorphisms (1 intronic and 1 in 3¢-UTR) were identified. Two low frequency ASA polymorphisms (2723A > G, W193C) were found to be correlated with low activity, while another low frequency ASA polymorphism (1101+123C > T) was found to be correlated with high activity in a population of 113 individuals. Real time PCR was used to measure mRNA levels of GBA, ASA and LF3 along with enzyme activity levels of GBA and ASA in two cell types (leucocytes and skin fibroblasts) from four healthy individuals and seven cell lines (HL60, THP1, Huh7, U118, SW1353, Hep G2, and B-cells). Transcriptional control was evident for all three genes with GBA mRNA levels varying over 30 fold, ASA mRNA levels varying over seven fold and ILF3 levels varying more than 24 fold. The 5¢-flanking region of GBA was investigated for the cis-elements responsible for tissue-specific expression. However, it was not possible to demonstrate that the cis-element region was influencing GBA expression. Translational efficiency was measured using the magnitude of the mRNA:enzyme activity ratio as an indicator. GBA translational inefficiency was most pronounced in B cells which require four times more mRNA molecules than hepatocytes (Hep G2) and over 25 times more mRNA molecules than chondrocytes (SW1353) to produce one unit of GBA enzyme activity. Except in B-cells, GBA translational efficiency appears to increase as ILF3 mRNA levels decrease. The tissue-specific variation observed in the protein levels of the ILF3 splice variants, TCP80 and DRBP76, may play a role. The correlation of several low frequency SNPs with low ASA enzyme activity or high ASA activity indicates a role in determining the distribution of enzyme activity levels in the normal population. However, there do not appear to be any common high activity polymorphisms. Knowledge of the exact mechanisms responsible for the observed transcriptional and translational control of these lysosomal genes will greatly enhance the understanding of genotype-phenotype correlation and the contribution of genetic variants to natural variation.
16

Patobiochemie lysosomálních střádavých onemocnění: studie Fabryho nemoci a příprava buněčných modelů X-vázaných chorob. / Pathobiochemistry of lysosomal storage disorders: Study of Fabry disease and generation of cellular models of X-linked disorders.

Rybová, Jitka January 2018 (has links)
Human autopsy or biopsy tissue samples, mouse models and cell cultures of various types represent the most common materials in the investigation of cell pathogenesis of inherited diseases. This dissertation is devoted to all these approaches in the study of two X-linked lysosomal storage diseases, Fabry disease (FD,α-galactosidase A (AGAL) deficiency) and mucopolysaccharidosis type II (MPSII, idunorate-2- sulfatase (IDS) deficiency). The primary goal of the work was analysis of lipid blood group B antigens with terminal α-galactose (B-GSL) in the pancreas of FD patients with blood group B (FD-B).,In addition to the main glycosphingolipid (GSL) substrate, globotriaosylceramide (Gb3Cer), B-GSLs represent another minor substrate of AGAL. The deposition of undegraded B-GSL has been demonstrated in FD-B pancreas where it was significantly higher than in other organs such as the kidneys and lungs which accumulate mainly Gb3Cer. High concentration of lipid and non-lipid B-antigens was primarily confirmed in exocrine acinar epithelial cells of FD-B, accompanied by massive accumulation of ceroid (secondary sign of lysosomal storage). Unlike acini, the endocrine portion of the pancreas remained unaffected by accumulation of AGAL substrates. This interesting phenomenon of cell biology shows how a specific...
17

Avaliação do uso de amostras de leucócitos impregnados em papel filtro para o diagnóstico de doenças lisossômicas

Camelier, Marli Teresinha Viapiana January 2016 (has links)
Introdução: As Doenças lisossômicas (DLs) são condições genéticas, herdadas na sua maioria de forma autossômica recessiva, caracterizadas usualmente pela deficiência de enzimas lisossômicas específicas, envolvidas na síntese, degradação, armazenamento ou transporte de macromoléculas necessárias para o funcionamento normal do organismo. Nas situações mais típicas, o substrato não degradado acumula-se progressivamente nos lisossomos, com repercussões estruturais e funcionais, levando a sinais e sintomas característicos. Os pacientes apresentam um amplo espectro de manifestações clínicas, que podem incluir disfunção de órgãos, anormalidades esqueléticas, envolvimento neuronal, entre outras. O diagnóstico é usualmente obtido pela identificação da deficiência enzimática específica em leucócitos obtidos do sangue periférico, usualmente realizado em laboratórios de referência. O transporte da amostra pode ser um obstáculo quando o serviço requisitante está situado longe do centro de referência ou em outro país, situação em que a amostra de sangue pode chegar ao laboratório já sem condições de ser analisada. Objetivo: Este estudo teve como objetivo principal, tornar disponível um método mais simples, seguro e acessível que utiliza amostras de leucócitos impregnados em papel filtro (LIPF) como uma nova ferramenta para o diagnóstico bioquímico de pacientes com DLs. Métodos: O estudo envolveu amostras de pacientes com diagnóstico previamente confirmado de DLs (amostra de conveniência, por se tratarem de doenças raras, com incidências individuais ao redor de 1:100.000 recém-nascidos vivos). Foram incluídos no estudo os pacientes com diagnóstico já estabelecido de DLs selecionadas (MPS IVA, Doença de Krabbe, Doença de Gaucher e Doença de Pompe), independente do sexo e/ou idade, atendidos no Serviço de Genética Médica do HCPA, que concordaram em participar do estudo. O grupo de referência negativo foi constituído pelas amostras de 50 indivíduos hígidos, adultos, de ambos os sexos. Resultados: Os resultados obtidos nos ensaios enzimáticos de pacientes com MPS IVA, Doença de Krabbe, Doença de Gaucher e Doença de Pompe, indicaram que as enzimas analisadas em amostras de LIPF permitiram a identificação de todos os pacientes, com sensibilidade de 100%. Os testes de estabilidade realizados nas amostras de LIPF indicaram que as amostras, quando mantidas a 4ºC, se mostram estáveis por pelo menos 30 dias. Conclusões: Nas condições utilizadas, amostras de LIPF se mostraram adequadas para a identificação segura de pacientes com MPS tipo IVA, Doença de Krabbe, Doença de Gaucher e Doença de Pompe. As amostras de leucócitos secos em papel filtro são mais estáveis e seguras para o transporte, indicando que possa ser esta uma importante ferramenta para facilitar a identificação de pacientes com DLDs, especialmente daqueles que vivem em áreas que tem dificuldades para a remessa de amostras líquidas para serviços de referência. / Background: Lysosomal Disorders (LDs) are genetic conditions, mostly inherited in autosomal recessive fashion, usually characterized by a deficiency of specific lysosomal enzymes involved in the synthesis, degradation, storage or transportation of macromolecules necessary for normal functioning of the organism. Typically, the non-degraded substrate is progressively accumulated in lysosomes, with structural and functional repercussions, leading to characteristic signs and symptoms. Affected patients present a wide range of clinical manifestations, which may include organ dysfunction, skeletal anomalies, neuronal involvement, etc. The diagnosis is normally made through identification of the specific enzyme deficiency in white blood cells from a sample of peripheral blood, usually performed in reference laboratories. The transporting of a liquid sample can be a problem when the test orderer is located far from the reference center or in a foreign country, as often the blood sample arrives at the laboratory in poor condition and cannot be properly analyzed. Aim: The main aim of this study was to make available a new technique that is simpler, safer and more accessible, using leukocytes impregnated on filter paper (LIFP) as a new tool for the biochemical diagnosis of patients with LSDs. Methods: This study involved samples of patients with previously confirmed diagnosis of selected LSDs (a convenience sample, as these are rare diseases, with individual incidences around 1:100.000 live newborns). Patients with an established diagnosis of MPS IVA, Krabbe Disease, Gaucher’s disease and Pompe disease regardless of sex and/or age, cared for at the Genetics Service of HCPA and who agreed to participate were included in the study. The negative reference group comprised blood samples from 50 healthy adults of both genders. Results: The results obtained in the enzymatic assays of patients with MPS IVA, Krabbe Disease, Gaucher’s disease, and Pompe disease indicated that the analyzed enzymes in LIFP samples allowed the identification of all patients, with sensitivity of 100%. The stability tests performed in LIFP samples indicated that samples, when maintained at 4ºC, were stable for at least 30 days. Conclusions: In the conditions used, LIFP samples were shown to be adequate for a reliable identification of patients with MPS IVA, Krabbe Disease, Gaucher’s disease, and Pompe disease. Blood samples on filter paper are more stable and reliable for transportation, indicating that this may be an important tool to facilitate the identification of patients with LSDs, particularly those living in areas with difficulties for the shipment of liquid samples to reference cervices.
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Avaliação do uso de amostras de leucócitos impregnados em papel filtro para o diagnóstico de doenças lisossômicas

Camelier, Marli Teresinha Viapiana January 2016 (has links)
Introdução: As Doenças lisossômicas (DLs) são condições genéticas, herdadas na sua maioria de forma autossômica recessiva, caracterizadas usualmente pela deficiência de enzimas lisossômicas específicas, envolvidas na síntese, degradação, armazenamento ou transporte de macromoléculas necessárias para o funcionamento normal do organismo. Nas situações mais típicas, o substrato não degradado acumula-se progressivamente nos lisossomos, com repercussões estruturais e funcionais, levando a sinais e sintomas característicos. Os pacientes apresentam um amplo espectro de manifestações clínicas, que podem incluir disfunção de órgãos, anormalidades esqueléticas, envolvimento neuronal, entre outras. O diagnóstico é usualmente obtido pela identificação da deficiência enzimática específica em leucócitos obtidos do sangue periférico, usualmente realizado em laboratórios de referência. O transporte da amostra pode ser um obstáculo quando o serviço requisitante está situado longe do centro de referência ou em outro país, situação em que a amostra de sangue pode chegar ao laboratório já sem condições de ser analisada. Objetivo: Este estudo teve como objetivo principal, tornar disponível um método mais simples, seguro e acessível que utiliza amostras de leucócitos impregnados em papel filtro (LIPF) como uma nova ferramenta para o diagnóstico bioquímico de pacientes com DLs. Métodos: O estudo envolveu amostras de pacientes com diagnóstico previamente confirmado de DLs (amostra de conveniência, por se tratarem de doenças raras, com incidências individuais ao redor de 1:100.000 recém-nascidos vivos). Foram incluídos no estudo os pacientes com diagnóstico já estabelecido de DLs selecionadas (MPS IVA, Doença de Krabbe, Doença de Gaucher e Doença de Pompe), independente do sexo e/ou idade, atendidos no Serviço de Genética Médica do HCPA, que concordaram em participar do estudo. O grupo de referência negativo foi constituído pelas amostras de 50 indivíduos hígidos, adultos, de ambos os sexos. Resultados: Os resultados obtidos nos ensaios enzimáticos de pacientes com MPS IVA, Doença de Krabbe, Doença de Gaucher e Doença de Pompe, indicaram que as enzimas analisadas em amostras de LIPF permitiram a identificação de todos os pacientes, com sensibilidade de 100%. Os testes de estabilidade realizados nas amostras de LIPF indicaram que as amostras, quando mantidas a 4ºC, se mostram estáveis por pelo menos 30 dias. Conclusões: Nas condições utilizadas, amostras de LIPF se mostraram adequadas para a identificação segura de pacientes com MPS tipo IVA, Doença de Krabbe, Doença de Gaucher e Doença de Pompe. As amostras de leucócitos secos em papel filtro são mais estáveis e seguras para o transporte, indicando que possa ser esta uma importante ferramenta para facilitar a identificação de pacientes com DLDs, especialmente daqueles que vivem em áreas que tem dificuldades para a remessa de amostras líquidas para serviços de referência. / Background: Lysosomal Disorders (LDs) are genetic conditions, mostly inherited in autosomal recessive fashion, usually characterized by a deficiency of specific lysosomal enzymes involved in the synthesis, degradation, storage or transportation of macromolecules necessary for normal functioning of the organism. Typically, the non-degraded substrate is progressively accumulated in lysosomes, with structural and functional repercussions, leading to characteristic signs and symptoms. Affected patients present a wide range of clinical manifestations, which may include organ dysfunction, skeletal anomalies, neuronal involvement, etc. The diagnosis is normally made through identification of the specific enzyme deficiency in white blood cells from a sample of peripheral blood, usually performed in reference laboratories. The transporting of a liquid sample can be a problem when the test orderer is located far from the reference center or in a foreign country, as often the blood sample arrives at the laboratory in poor condition and cannot be properly analyzed. Aim: The main aim of this study was to make available a new technique that is simpler, safer and more accessible, using leukocytes impregnated on filter paper (LIFP) as a new tool for the biochemical diagnosis of patients with LSDs. Methods: This study involved samples of patients with previously confirmed diagnosis of selected LSDs (a convenience sample, as these are rare diseases, with individual incidences around 1:100.000 live newborns). Patients with an established diagnosis of MPS IVA, Krabbe Disease, Gaucher’s disease and Pompe disease regardless of sex and/or age, cared for at the Genetics Service of HCPA and who agreed to participate were included in the study. The negative reference group comprised blood samples from 50 healthy adults of both genders. Results: The results obtained in the enzymatic assays of patients with MPS IVA, Krabbe Disease, Gaucher’s disease, and Pompe disease indicated that the analyzed enzymes in LIFP samples allowed the identification of all patients, with sensitivity of 100%. The stability tests performed in LIFP samples indicated that samples, when maintained at 4ºC, were stable for at least 30 days. Conclusions: In the conditions used, LIFP samples were shown to be adequate for a reliable identification of patients with MPS IVA, Krabbe Disease, Gaucher’s disease, and Pompe disease. Blood samples on filter paper are more stable and reliable for transportation, indicating that this may be an important tool to facilitate the identification of patients with LSDs, particularly those living in areas with difficulties for the shipment of liquid samples to reference cervices.
19

Tandemová hmotnostní spektrometrie sfingolipidů s aplikací pro metabolické studie a diagnostiku sfingolipidos / Tandemová hmotnostní spektrometrie sfingolipidů s aplikací pro metabolické studie a diagnostiku sfingolipidos

Kuchař, Ladislav January 2013 (has links)
In recent years, mass spectrometry (MS) become the dominant technology in lipidomic analysis and widely influenced research and diagnosis of diseases of lipid metabolism, e.g. lysosomal storage disorders (LSD) characterized by impairment of the lysosomal functions. Defects in lysosomal processing of sphingolipids SFL belong to the category of sphingolipidoses. This condition has severe and even fatal clinical outcome. The primary aim of this work was to establish quantitative and qualitative methods of SFL analysis useful for research and diagnosis of LSD. At first, semisynthesis of mass labeled lipid standards utilizing immobilized sphingolipid ceramide N-deacylase was performed. Established methods of quantitative analysis were then used to prove the increased excretion of urinary SFL in LSD with characteristic storage in the kidney. Determination of excreted urinary SFL was found useful for differential diagnosis of prosaposin and saposin B deficiences for which routine enzymology is failing. MS also enabled monitoring of individual molecular species (isoforms) of SFL, which led to the finding that their urinary pattern is changing in some LSD. This resulted in the development of new screening method in dry urinary samples based on isoform profile evaluation. Another MS application referred to...
20

Charakterizace promotorových oblastí genů HGSNAT a GBA, a příspěvek ke studiu patogeneze MPS IIIC a Gaucherovy choroby / Characterization of promoter regions of HGSNAT and GBA genes, and a contribution to the study of pathogenesis of MPS IIIC and Gaucher disease

Richtrová, Eva January 2014 (has links)
Pathogenesis of mucopolysaccharidosis type IIIC (MPS IIIC) and Gaucher disease has not been yet fully clarified, and the causes of phenotypical variability between the patients with the same genotype in Gaucher disease remain obscure. Because the variants in the regulatory regions of genes can cause phenotypical differences mentioned above, I have studied promoter regions of HGSNAT and GBA genes mutated in these lysosomal disorders. I have shown that there is an alternative promoter of GBA (P2). Additional studies were aimed to elucidate possible physiological functions of P2, and its possible role in the pathogenesis of Gaucher disease. I have found that P2 is not tissue specific, and that its variants do not influence the variability of phenotype in Gaucher patients with the same genotype. P2 is used differentially neither during the differentiation of monocytes to macrophages nor in macrophages from controls and Gaucher patients, in whom there is a prominent storage only in cells of macrophage origin. We have thus not found any changes that would suggest a role for P2 in the pathogenesis of Gaucher disease. I have characterized the promoter region of HGSNAT and shown that the binding of Sp1 transcription factor is important for its expression. Sequence variants found in HGSNAT promoter in...

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