Sökresultat

Filtyp

Din sökning på "*" gav 529814 sökträffar

Vitamin B6 Vitamer concentrations in cerebrospinal fluid differ between preterm and termnewborn infants

BACKGROUND AND OBJECTIVE: Vitamin B6 plays a pivotal role in brain development and functioning. Differences in vitamin B6 homeostasis between preterm and term newborn infants have been reported. The authors sought to investigate whether B6 vitamers in cerebrospinal fluid (CSF) of preterm and term newborn infants are different. METHODS: B6 vitamer concentrations were determined in 69 CSF samples of

Increased concentrations of both NMDA receptor co-agonists d-serine and glycine in global ischemia : A potential novel treatment target for perinatal asphyxia

Worldwide, perinatal asphyxia is an important cause of morbidity and mortality among term-born children. Overactivation of the N-methyl-d-aspartate receptor (NMDAr) plays a central role in the pathogenesis of cerebral hypoxia-ischemia, but the role of both endogenous NMDAr co-agonists d-serine and glycine remains largely elusive. We investigated d-serine and glycine concentration changes in rat gl

Identification of a human trans-3-hydroxy-L-proline dehydratase, the first characterized member of a novel family of proline racemase-like enzymes

A family of eukaryotic proline racemase-like genes has recently been identified. Several members of this family have been well characterized and are known to catalyze the racemization of free proline or trans-4-hydroxyproline. However, the majority of eukaryotic proline racemase-like proteins, including a human protein called C14orf149, lack a specific cysteine residue that is known to be critical

Quantification of vitamin B6 vitamers in human cerebrospinal fluid by ultra performance liquid chromatography-tandem mass spectrometry

Since vitamin B6 is essential for normal functioning of the central nervous system, there is growing need for sensitive analysis of B6 vitamers in cerebrospinal fluid (CSF). This manuscript describes the development and validation of a rapid, sensitive and accurate method for quantification of the vitamin B6 vitamers pyridoxal (PL), pyridoxamine (PM), pyridoxine (PN), pyridoxic acid (PA), pyridoxa

A sensitive and simple ultra-high-performance-liquid chromatography-tandem mass spectrometry based method for the quantification of d-amino acids in body fluids

d-Amino acids are increasingly being recognized as important signaling molecules in mammals, including humans. d-Serine and d-aspartate are believed to act as signaling molecules in the central nervous system. Interestingly, several other d-amino acids also occur in human plasma, but very little is currently known regarding their function and origin. Abnormal levels of d-amino acids have been impl

Orthopaedic management of Hurler's disease after hematopoietic stem cell transplantation : A systematic review

Objective: The introduction of hematopoietic stem cell transplantation (HSCT) has significantly improved the life-span of Hurler patients (mucopolysaccharidosis type I-H, MPS I-H). Yet, the musculoskeletal manifestations seem largely unresponsive to HSCT. In order to facilitate evidence based management, the aim of the current study was to give a systematic overview of the orthopaedic complication

D-Serine : The right or wrong isoform?

Only recently, d-amino acids have been identified in mammals. Of these, d-serine has been most extensively studied. d-Serine was found to play an important role as a neurotransmitter in the human central nervous system (CNS) by binding to the N-methyl-d-aspartate receptor (NMDAr), similar to glycine. Therefore, d-serine may well play a role in all physiological and pathological processes in which

Intracranial bleeding due to vitamin K deficiency : Advantages of using a pediatric intensive care registry

Aim: To determine the incidence of late intracranial vitamin K deficiency bleeding (VKDB) in The Netherlands using the Dutch Pediatric Intensive Care Evaluation (PICE) registry. Methods: The PICE registry was used to identify all infants who were admitted to a Dutch pediatric intensive care unit (PICU) with intracranial bleeding between 1 January 2004 and 31 December 2007. Cases of confirmed late

Expanding the clinical spectrum of 3-phosphoglycerate dehydrogenase deficiency

3-Phosphoglycerate dehydrogenase (3-PGDH) deficiency is considered to be a rare cause of congenital microcephaly, infantile onset of intractable seizures and severe psychomotor retardation. Here, we report for the first time a very mild form of genetically confirmed 3-PGDH deficiency in two siblings with juvenile onset of absence seizures and mild developmental delay. Amino acid analysis showed se

Metabolic profiles in children during fasting

BACKGROUND: Hypoglycemia is one of the most common metabolic derangements in childhood. To establish the cause of hypoglycemia, fasting tolerance tests can be used. Currently available reference values for fasting tolerance tests have limitations in their use in daily practice. OBJECTIVE: The aim of this study was to determine the reference values of metabolites involved in glucose homeostasis dur

Whole body composition analysis by the BodPod air-displacement plethysmography method in children with Phenylketonuria shows a higher body fat percentage

Background Phenylketonuria (PKU) causes irreversible central nervous system damage unless a phenylalanine (PHE) restricted diet with amino acid supplementation is maintained. To prevent growth retardation, a protein/amino acid intake beyond the recommended dietary protein allowance is mandatory. However, data regarding disease and/or diet related changes in body composition are inconclusive and re

Fatal cerebral edema associated with serine deficiency in CSF

Two young girls without a notable medical history except for asthma presented with an acute toxic encephalopathy with very low serine concentrations both in plasma and cerebrospinal fluid (CSF) comparable to patients with 3-phosphoglycerate dehydrogenase (3-PGDH) deficiency. Clinical symptoms and enzyme measurement (in one patient) excluded 3-PGDH deficiency. Deficiencies in other serine biosynthe

Hydrolysed formula is a risk factor for vitamin K deficiency in infants with unrecognised cholestasis

OBJECTIVES:: Vitamin K deficiency (VKD) may cause life-threatening haemorrhages, especially in breast-fed infants with unrecognised cholestasis. Interestingly, hypoallergenic formulas appear overrepresented in reported cases of VKD bleeding (VKDB) in formula-fed infants. We therefore assessed whether the risk of VKD in formula-fed infants with cholestasis is associated with hypoallergenic formulas

Magnetic resonance imaging pattern recognition in hypomyelinating disorders

Hypomyelination is observed in the context of a growing number of genetic disorders that share clinical characteristics. The aim of this study was to determine the possible role of magnetic resonance imaging pattern recognition in distinguishing different hypomyelinating disorders, which would facilitate the diagnostic process. Only patients with hypomyelination of known cause were included in thi

Multicentre age-related reference intervals for cerebrospinal fluid serine concentrations : Implications for the diagnosis and follow-up of serine biosynthesis disorders

The disorders of serine biosynthesis are a group of inborn errors of metabolism characterised by congenital microcephaly, seizures and severe psychomotor retardation. Although these disorders are rare the prompt recognition of serine deficiency is important as these disorders are treatable. The diagnosis is based on decreased concentrations of serine in cerebrospinal fluid (CSF). It has previously

No title

In this clinical case, the importance of early detection of Hurler syndrome for outcomes of stem cell transplantation in this patient population is illustrated. Nowadays, children with Hurler syndrome can be treated with stem cell transplantation, but the results largely depend on the moment of treatment. If the procedure is initiated in an early stage of disease, better results can be obtained. T

Fatal outcome due to deficiency of subunit 6 of the conserved oligomeric Golgi complex leading to a new type of congenital disorders of glycosylation

Deficiency of subunit 6 of the conserved oligomeric Golgi (COG6) complex causes a new combined N-and O-glycosylation deficiency of the congenital disorders of glycosylation, designated as CDG-IIL (COG6-CDG). The index patient presented with a severe neurologic disease characterized by vitamin K deficiency, vomiting, intractable focal seizures, intracranial bleedings and fatal outcome in early infa

Dried Blood Spot Analysis : An Easy and Reliable Tool to Monitor the Biochemical Effect of Hematopoietic Stem Cell Transplantation in Hurler Syndrome Patients

Hurler syndrome (HS), the most severe phenotype in the spectrum of mucopolysaccharidosis type I, is caused by a deficiency of the lysosomal enzyme alpha-L-iduronidase (IDUA). At present, hematopoietic stem cell transplantation (HSCT) is the only treatment able to prevent disease progression in the central nervous system, and therefore considered the treatment of choice in HS patients. Because IDUA

Liquid chromatography-tandem mass spectrometry assay for the quantification of free and total sialic acid in human cerebrospinal fluid

Background: Analysis of sialic acid (SA) metabolites in cerebrospinal fluid (CSF) is important for clinical diagnosis. In the present study, a high-performance liquid chromatography-tandem mass spectrometry (HPLC/MS/MS) method for free sialic acid (FSA) and total sialic acid (TSA) in human CSF was validated. Methods: The method utilized a simple sample-preparation procedure of protein precipitatio