ABSTRACT
An unknown urinary amino acid, present in small amounts in many children with various diseases, has been isolated and identified as N-Epsilon-(carboxymethyl)lysine. The identity of this compound was confirmed by synthesis. Its chromatographical characteristics are described. The compound also occurred in the urine of prematurely born infants. Even in healthy adults trace amounts could be detected. In a few patients strikingly higher excretions were observed, up to 67 mg/g creatinine, as determined by cation-exchange column chromatography. No clear correlation with a distinct clinical picture could be established. Speculations are given about the origin of the compound.
Subject(s)
Lysine/analogs & derivatives , Adolescent , Adult , Chemical Phenomena , Chemistry , Child , Child, Preschool , Creatinine/urine , Female , Humans , Infant , Infant, Newborn , Infant, Premature , Lysine/metabolism , Lysine/urine , PregnancyABSTRACT
The occurrence of gamma-glutamylphenylalanine in the urine of patients with phenylketonuria could be demonstrated using chromatographic techniques and mass spectrometry. Concentrations ranged up to 35 mg/l. Only a weak correlation between the urinary excretion of this compound and phenylalanine was seen. The ages of the patients investigated ranged from 2 weeks to 18 years. The origin of the dipeptide is discussed.
Subject(s)
Dipeptides/urine , Phenylketonurias/urine , Adolescent , Child , Child, Preschool , Chromatography, Gas , Chromatography, Thin Layer , Female , Humans , Infant , Infant, Newborn , Mass Spectrometry , Phenylalanine/blood , Phenylalanine/urineABSTRACT
Tyrosyluria and for a part also tyrosinemia were studied in 60 healthy prematures of various birth weights and gestational ages. The first analyses were performed between the 6th and the 14th day after birth. A normal milk diet was given and the protein-intake was between 3 and 4 g/kg. After the first collection of urine half the patients received extra ascorbic acid, 100 mg/kg daily. Urinary analyses of tyrosine and p-hydroxyphenyl metabolites were performed once a week, until the excretion of p-hydroxyphenylpyruvic plus p-hydroxyphenyllactic acids was lower than 5 mmoles per gram creatinine. In 22 out of the 60 prematures (or 37%) a tyrosyluria of more than 5 mmoles/g creatinine and in 19 out of 44 (43%) patients analysed serum tyrosine was higher than 5 mg/100 ml at first analysis. No inverse correlation between tyrosyluria and tyrosinemia on the one hand and birth weight and gestational age on the other hand existed. But in children with a delayed intra-uterine development the incidence of tyrosyluria was higher as prematurity was more pronounced. Ascorbic acid had no effect on the rate of disappearance of tyrosyluria. It was concluded that the addition of extra vitamin C to the diet of prematures is not useful for the normalization of tyrosine metabolism.
Subject(s)
Ascorbic Acid/therapeutic use , Infant Nutrition Disorders/diagnosis , Infant Nutrition Disorders/drug therapy , Infant, Premature , Tyrosine/metabolism , Animals , Birth Weight , Creatinine/blood , Diet , Dietary Proteins , Female , Gestational Age , Humans , Hydroxybenzoates/urine , Infant, Newborn , Male , Methionine/blood , Milk , Phenylacetates/urine , Pregnancy , Time Factors , Tyrosine/blood , Tyrosine/urineABSTRACT
1. The metabolic fate of orally given deuterated L-tyrosine, 50 mg/kg body weight, was investigated in seven patients with tyrosinemia type I in order to obtain evidence that the primary defect is at the level of fumarylacetoacetase. 2. The absence of fumarylacetoacetase could be proved in liver biopsy specimens obtained from four patients. 3. All patients excreted deuterated succinylacetoacetate and deuterated succinylacetone was detected in six out of seven. The total amount of these compounds was rather low; maximal 8.3% of the dose. The peak of the excretion occurred 3-6 h after loading, indicating an endogenous formation of the metabolites. 4. All patients excreted deuterated 4-hydroxyphenyl acids, probably reflecting secondary 4-hydroxyphenylpyruvate dioxygenase deficiency connected with liver damage. 5. No evidence for other secondary routes of tyrosine metabolism was found.
Subject(s)
Acetoacetates/urine , Amino Acid Metabolism, Inborn Errors/urine , Heptanoates/urine , Heptanoic Acids/urine , Hydrolases/deficiency , Tyrosine/blood , 4-Hydroxyphenylpyruvate Dioxygenase/deficiency , Deuterium , Female , Humans , Infant , Liver/enzymology , Male , Tyrosine/urineABSTRACT
Patients with 3-hydroxy-3-methylglutaric aciduria due to a deficiency of 3-hydroxy-3-methylglutaryl Coenzyme A lyase usually present with a life-threatening crisis of hypoglycemia, metabolic acidosis and hyperammonemia. Diagnosis of this inborn error of leucine degradation is usually based upon gas-chromatographic analysis of organic acids in a patient's urine. In this paper we describe a simple spectrophotometric method allowing the activity of HMG-CoA lyase to be measured in leukocytes or platelets within a few hours, thus contributing to a rapid, unequivocal diagnosis and subsequent treatment. The validity of the method was established by demonstrating a deficient activity of HMG-CoA lyase in two patients with 3-hydroxy-3-methylglutaric aciduria. Furthermore, using this method, heterozygote detection can be done with great reliability.
Subject(s)
Blood Platelets/enzymology , Leukocytes/enzymology , Oxo-Acid-Lyases/deficiency , Child, Preschool , Female , Humans , Hydrogen-Ion Concentration , Infant , Infant, Newborn , Male , Metabolism, Inborn Errors/blood , Metabolism, Inborn Errors/diagnosis , Oxo-Acid-Lyases/blood , Spectrophotometry/methodsSubject(s)
Amino Acid Metabolism, Inborn Errors/enzymology , Carbohydrate Metabolism, Inborn Errors/enzymology , Fructose-1,6-Diphosphatase Deficiency , Tyrosine/metabolism , Alanine/blood , Amino Acid Metabolism, Inborn Errors/diagnosis , Amino Acids/blood , Amino Acids/urine , Carbohydrate Metabolism, Inborn Errors/diagnosis , Chromatography, Gas , Cystathionine/urine , Dietary Carbohydrates/metabolism , Female , Fructose-Bisphosphatase/metabolism , Humans , Infant , Lactates/urine , Methionine/blood , Phenylalanine/urine , Sucrose/metabolism , Tyrosine/urineSubject(s)
Amino Acid Metabolism, Inborn Errors/blood , Amino Acid Metabolism, Inborn Errors/urine , Chromatography , Acetates/urine , Acrylates/urine , Adolescent , Adult , Amino Acid Metabolism, Inborn Errors/drug therapy , Autoanalysis , Buffers , Child , Child, Preschool , Colorimetry , Creatine/urine , HumansSubject(s)
Amino Acid Metabolism, Inborn Errors/therapy , Diet Therapy , Histamine/metabolism , Amino Acid Metabolism, Inborn Errors/blood , Amino Acid Metabolism, Inborn Errors/urine , Child , Creatinine/urine , Dietary Proteins , Electroencephalography , Fasting , Histidine/blood , Histidine/urine , Humans , Imidazoles/blood , Imidazoles/urine , MaleSubject(s)
Purine-Pyrimidine Metabolism, Inborn Errors/metabolism , Pyrimidines/metabolism , Child, Preschool , Chromatography, Gas , Gas Chromatography-Mass Spectrometry , Humans , Purine-Pyrimidine Metabolism, Inborn Errors/diagnosis , Purines/urine , Pyrimidines/urine , Thymine/urine , Uracil/urineSubject(s)
Metabolism, Inborn Errors/diagnosis , Biological Transport , DNA, Recombinant/analysis , Deficiency Diseases/diagnosis , Enzymes/analysis , Enzymes/biosynthesis , Female , Humans , Infant , Malabsorption Syndromes/diagnosis , Male , Membrane Proteins/metabolism , Metabolism, Inborn Errors/enzymologySubject(s)
Amino Acid Metabolism, Inborn Errors , Liver Diseases/metabolism , Tyrosine/metabolism , Acute Disease , Amino Acid Metabolism, Inborn Errors/complications , Ascorbic Acid/therapeutic use , Chronic Disease , Female , Growth Disorders/etiology , Hematuria/etiology , Humans , Infant, Newborn , Liver/pathology , Liver Diseases/diet therapy , Male , Methionine/metabolism , PregnancySubject(s)
Amino Acid Metabolism, Inborn Errors/diagnosis , Malonates/metabolism , Methylmalonic Acid/metabolism , Acidosis/metabolism , Amino Acid Metabolism, Inborn Errors/therapy , Female , Humans , Infant , Infant, Newborn , Intellectual Disability/etiology , Male , Methylmalonic Acid/urine , Methylmalonyl-CoA Mutase/metabolismABSTRACT
In 6 patients with PKU, being on a low phenylalanine diet, the effect of reintroduction of phenylalanine on the E.E.G. was studied. The children, therefore, received daily loads of 100 or 150 mg phenylalanine/Kg bodyweight, equally divided over the meals. Computerized spectral analysis of the E.E.G's was performed during and after the loading tests. This made quantification possible of the following E.E.G. changes: 1) the increase of activities in the theta frequency band (4-8 Hz); 2) the frequency change of the alpha rhythm; 3) the change of the degree of synchrony between identical frequencies occurring in different derivations. A linear relation was found between these quantified E.E.G. parameters and the phenylalanine blood-level. After stopping the loading test E.E.G. abnormalities reversed suggesting that they could be considered as a measure for the degree of intoxication caused by the phenylalanine and/or its metabolites. It is suggested that the E.E.G. data may be useful parameters for alleviation or termination of the diet.
Subject(s)
Computers , Electroencephalography/methods , Phenylketonurias/diet therapy , Alpha Rhythm , Cerebral Cortex/physiopathology , Child , Evaluation Studies as Topic , Humans , Phenylalanine/blood , Phenylketonurias/physiopathology , Theta RhythmABSTRACT
The effect on the EEG of the reintroduction of phenylalanine in the diet of 6 patients with PKU on treatment was studied. Patients received daily loads of 100 or 150 mg L-phenylalanine/kg, equally divided over the meals, and computerized spectral EEG analysis was performed. The following EEG changes were seen: (1) occurrence of activity in the low frequency band (2--5 c/sec), (2) change of frequency of dominant rhythms; (3) change in the degree of synchrony between identical frequencies, occurring in different derivations. EEG changes increased quantitatively parallel to increasing blood phenylalanine and reversed after stopping the phenylalanine administration, suggesting that the EEG abnormalities are a measure for the degree of intoxication caused by phenylalanine or its metabolites. It is suggested that the EEG data may be useful deciding to terminate the diet in PKU.
Subject(s)
Electroencephalography , Phenylalanine/blood , Phenylketonurias/diet therapy , Adolescent , Brain/physiopathology , Child , Child, Preschool , Diagnosis, Computer-Assisted , Humans , Infant , Infant, Newborn , Phenylalanine/poisoning , Phenylalanine/therapeutic use , Phenylketonurias/blood , Phenylketonurias/physiopathologyABSTRACT
Two sisters with isovaleric acidaemia are described. Both had multiple attacks of acetonaemic vomiting, sometimes leading to subcoma. Despite this they showed a completely normal mental development. Biochemical studies, clinical follow-up and attempts at treatment are presented.
Subject(s)
Acidosis/etiology , Amino Acid Metabolism, Inborn Errors/genetics , Intelligence , Ketosis/etiology , Valerates/blood , Amino Acid Metabolism, Inborn Errors/complications , Coma/etiology , Female , Humans , Vomiting/etiologyABSTRACT
Two male sibs with cerebro-costo-mandibular syndrome and spina bifida are described. The parents are physically and radiologically normal. A short review of the pertinent literature is given with special emphasis on the mode of inheritance.
Subject(s)
Abnormalities, Multiple/genetics , Mandible/abnormalities , Ribs/abnormalities , Spina Bifida Occulta/genetics , Child, Preschool , Humans , MaleABSTRACT
Two siblings were found to be affected by long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency, one of which died suddenly and unexpectedly on the 3rd day of life suffering from extreme hypoketotic hypoglycaemia. The younger sibling started to have feeding problems, lowered consciousness, and liver dysfunction at the age of 5 months. Her urine contained large amounts of C6-C14 3-hydroxydicarboxylic acids and conjugated 3-hydroxyoctanoic acid, as verified by gas chromatography/mass spectrometry. Plasma long-chain acylcarnitine was increased. A clue to the diagnosis was given by the results of a phenylpropionic acid loading test. This revealed small, but significant amounts of conjugated 3-hydroxyphenylpropionic acid (phenylhydracrylic acid) in the patient's urine. Subsequently, the activity of long-chain 3-hydroxyacyl-CoA dehydrogenase was found to be deficient in cultured skin fibroblasts. Based on the findings obtained by a medium-chain triglyceride load, a diet enriched in this type of fat was prescribed. On this regimen the patient started to thrive, signs of cardiomyopathy disappeared, and her liver function normalized.
Subject(s)
3-Hydroxyacyl CoA Dehydrogenases/deficiency , Dicarboxylic Acids/urine , Lipid Metabolism, Inborn Errors/diet therapy , Triglycerides/therapeutic use , Death, Sudden , Female , Humans , Infant , Infant, Newborn , Lipid Metabolism, Inborn Errors/blood , Lipid Metabolism, Inborn Errors/cerebrospinal fluidABSTRACT
The activity of medium-chain acyl-CoA dehydrogenase (MCAD) with octanoyl-CoA as a substrate was measured in human lymphocytes by a gas chromatographic technique. Phenazine methosulfate was used as the primary electron acceptor. After the addition of crotonase and subsequent hydrolysis, the reaction product 3-hydroxyoctanoic acid was quantitated by capillary gas-liquid chromatography of the trimethylsilyl derivatives. Control subjects had MCAD activities of 3.46 +/- 0.18 nmol/mg protein/min (n = 15). Five patients were investigated while receiving no therapy at all; MCAD activity ranged from 0.08 to 0.23 in four of them and was 0.65 in the fifth one. Subsequent to the long-term administration of 50-150 mg/d of riboflavin to MCAD-deficient patients (n = 11), these activities increased to an average of 0.41 in 10 patients and 2.22 in one. The activities in 15 obligate heterozygotes were 1.91 +/- 0.41 nmol/mg protein/min, thus enabling a clear distinction from controls. Neither heterozygotes nor a control responded to riboflavin. The method was also applicable to postmortem liver tissue. One patient, who had died suddenly and unexpectedly at the age of 19 mo, was correctly diagnosed as MCAD-deficient, whereas five additional children who died of the sudden infant death syndrome showed normal activities.