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São João da Madeira, Portugal

Rymen D.,Catholic University of Leuven | Rymen D.,University Hospital Gasthuisberg | Peanne R.,Catholic University of Leuven | Millon M.B.,National University of Cordoba | And 12 more authors.
PLoS Genetics | Year: 2013

Congenital disorders of glycosylation (CDG) are a group of rare metabolic diseases, due to impaired protein and lipid glycosylation. In the present study, exome sequencing was used to identify MAN1B1 as the culprit gene in an unsolved CDG-II patient. Subsequently, 6 additional cases with MAN1B1-CDG were found. All individuals presented slight facial dysmorphism, psychomotor retardation and truncal obesity. Generally, MAN1B1 is believed to be an ER resident alpha-1,2-mannosidase acting as a key factor in glycoprotein quality control by targeting misfolded proteins for ER-associated degradation (ERAD). However, recent studies indicated a Golgi localization of the endogenous MAN1B1, suggesting a more complex role for MAN1B1 in quality control. We were able to confirm that MAN1B1 is indeed localized to the Golgi complex instead of the ER. Furthermore, we observed an altered Golgi morphology in all patients' cells, with marked dilatation and fragmentation. We hypothesize that part of the phenotype is associated to this Golgi disruption. In conclusion, we linked mutations in MAN1B1 to a Golgi glycosylation disorder. Additionally, our results support the recent findings on MAN1B1 localization. However, more work is needed to pinpoint the exact function of MAN1B1 in glycoprotein quality control, and to understand the pathophysiology of its deficiency. © 2013 Rymen et al. Source


Decker C.,BioMarin Pharmaceutical | Yu Z.-F.,Statistics Collaborative Inc. | Giugliani R.,Federal University of Rio Grande do Sul | Schwartz I.V.D.,Federal University of Rio Grande do Sul | And 16 more authors.
Journal of Pediatric Rehabilitation Medicine | Year: 2010

Background and Methods: Growth failure is characteristic of untreated mucopolysaccharidosis type VI (MPS VI: Maroteaux-Lamy syndrome). Growth was studied in fifty-six MPS VI patients (5 to 29 years old) prior to and for up to 240 weeks of weekly infusions of recombinant human arylsulfatase B (rhASB) at 1 mg/kg during Phase 1/2, Phase 2, Phase 3 or Phase 3 Extension clinical trials. Height, weight, and Tanner stage data were collected. Pooled data were analyzed to determine mean height increase by treatment week, growth impacts of pubertal status, baseline urinary GAG, and age at treatment initiation. Growth rate for approximately 2 years prior to and following treatment initiation was analyzed using longitudinal modeling. Results: Mean height increased by 2.9 cm after 48 weeks and 4.3 cm after 96 weeks on enzyme replacement therapy (ERT). Growth on ERT was not correlated with baseline urinary GAG. Patients under 16~years of age showed greatest increases in height on treatment. Model results based on pooled data showed significant improvement in growth rate during 96~weeks of ERT when compared to the equivalent pretreatment time period. Delayed pubertal onset or progression was noted in 10 patients entering the clinical trials; all of whom showed progression of at least one Tanner stage during 2 years on ERT, and 6 of whom (60%) completed puberty. Conclusion: Analysis of mean height by treatment week and longitudinal modeling demonstrate significant increase in height and growth rate in MPS VI patients receiving long-term ERT. This impact was greatest in patients aged below 16 years. Height increase may result from bone growth and/or reduction in joint contractures. Bone growth and resolution of delayed puberty may be related to improvements in general health, bone cell health, nutrition, endocrine gland function and reduced inflammation. © 2010 IOS Press and the authors. Source


Kolker S.,University of Heidelberg | Cazorla A.G.,Servicio de Neurologia and CIBERER | Valayannopoulos V.,Institut Universitaire de France | Lund A.M.,Copenhagen University | And 47 more authors.
Journal of Inherited Metabolic Disease | Year: 2015

Background: The clinical presentation of patients with organic acidurias (OAD) and urea cycle disorders (UCD) is variable; symptoms are often non-specific. Aims/methods: To improve the knowledge about OAD and UCD the E-IMD consortium established a web-based patient registry. Results: We registered 795 patients with OAD (n = 452) and UCD (n = 343), with ornithine transcarbamylase (OTC) deficiency (n = 196), glutaric aciduria type 1 (GA1; n = 150) and methylmalonic aciduria (MMA; n = 149) being the most frequent diseases. Overall, 548 patients (69 %) were symptomatic. The majority of them (n = 463) presented with acute metabolic crisis during (n = 220) or after the newborn period (n = 243) frequently demonstrating impaired consciousness, vomiting and/or muscular hypotonia. Neonatal onset of symptoms was most frequent in argininosuccinic synthetase and lyase deficiency and carbamylphosphate 1 synthetase deficiency, unexpectedly low in male OTC deficiency, and least frequently in GA1 and female OTC deficiency. For patients with MMA, propionic aciduria (PA) and OTC deficiency (male and female), hyperammonemia was more severe in metabolic crises during than after the newborn period, whereas metabolic acidosis tended to be more severe in MMA and PA patients with late onset of symptoms. Symptomatic patients without metabolic crises (n = 94) often presented with a movement disorder, mental retardation, epilepsy and psychiatric disorders (the latter in UCD only). Conclusions: The initial presentation varies widely in OAD and UCD patients. This is a challenge for rapid diagnosis and early start of treatment. Patients with a sepsis-like neonatal crisis and those with late-onset of symptoms are both at risk of delayed or missed diagnosis. © 2015, SSIEM. Source


Braunlin E.,University of Minnesota | Rosenfeld H.,Childrens Hospital and Research Center Oakland | Kampmann C.,University Medicine | Johnson J.,Childrens Hospital and Research Center Oakland | And 20 more authors.
Journal of Inherited Metabolic Disease | Year: 2013

Characteristic cardiac valve abnormalities and left ventricular hypertrophy are present in untreated patients with mucopolysaccharidosis type VI (MPS VI). Cardiac ultrasound was performed to investigate these findings in subjects during long-term enzyme replacement therapy (ERT) with recombinant human arylsulfatase B (rhASB, rhN-acetylgalactosamine 4-sulfatase, galsulfase, Naglazyme®). Studies were conducted in 54 subjects before ERT was begun and at specific intervals for up to 96 weeks of weekly infusions of rhASB at 1 mg/kg during phase 1/2, phase 2, and phase 3 trials of rhASB. At baseline, mitral and aortic valve obstruction was present and was significantly greater in those ≥12 years of age. Mild mitral and trace aortic regurgitation were present, the former being significantly greater in those <12 years. Left ventricular hypertrophy, with averaged z-scores ranging from 1.6-1.9 SD greater than normal, was present for ages both <12 and ≥12 years. After 96 weeks of ERT, ventricular septal hypertrophy regressed in those <12 years. For those ≥12 years, septal hypertrophy was unchanged, and aortic regurgitation increased statistically but not physiologically. Obstructive gradients across mitral and aortic valves remained unchanged. The results suggest that long-term ERT is effective in reducing intraventricular septal hypertrophy and preventing progression of cardiac valve abnormalities when administered to those <12 years of age. © 2012 The Author(s). Source


Martins E.,Unidade de Doencas Metabolicas | Cardoso M.L.,University of Porto | Rodrigues E.,Unidade de Doencas Metabolicas | Barbot C.,Unidade de Doencas Metabolicas | And 4 more authors.
Journal of Inherited Metabolic Disease | Year: 2011

Short-chain 3-hydroxyacyl-CoA dehydrogenase (HADH, SCHAD) deficiency (OMIM #231530) represents a recently described disorder of mitochondrial fatty acid beta-oxidation, with less than ten cases described worldwide. The main clinical presentation of this metabolic disease is different from other inherited defects of fatty acid β-oxidation as the hypoglycemia is associated with hyperinsulinism. We present the clinical, biochemical and molecular findings of four new Caucasian patients with HADH deficiency. These new cases contribute to a more comprehensive description of the phenotype, diagnostic biomarkers and treatment options for this poorly defined disease. © 2011 SSIEM and Springer. Source

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