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1.
J Inherit Metab Dis ; 29(4): 588, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16802109

RESUMEN

L-2-Hydroxyglutaric aciduria (L-2-HGA) is a rare progressive neurometabolic disease, defined as a characteristic clinical and radiological entity, mainly including mental retardation, cerebellar dysfunction and involvement of the subcortical white matter, cerebellum and basal ganglia on brain MRI. The biochemical hallmark is an increased urinary excretion of L-2-hydroxyglutaric acid. Management is only supportive. A child born to a Turkish mother in whom L-2-HGA was previously diagnosed is reported. Although pregnancy was repeatedly advised against because of the important degree of mental retardation and the potential risk of a toxic effect on the embryo and/or fetus (at that time no reports of maternal L-2-HGA were available), she became pregnant at 30 years of age and the pregnancy passed uneventfully. On amniocentesis, performed at 5 months of gestational age, elevated 2-hydroxyglutarate, previously shown to be almost exclusively the L-2-stereoisomer, was present in the amniotic fluid: 27.5mu mol/L (controls <1.3; n=5). The child, not affected by the disease as shown by a normal urinary excretion of 2-hydroxyglutaric acid, was normal at birth. When last examined at the age of 3 years, both somatic and mental development were excellent. As the pathogenesis of the extensive brain damage in affected persons remains largely unknown, notwithstanding the recent identification of the mutated gene and the deficient enzyme, one can only speculate on the mechanism by which embryo and fetus from a L-2-HGA mother are spared, at least in this case.


Asunto(s)
Encefalopatías Metabólicas Innatas/fisiopatología , Glutaratos/orina , Complicaciones del Embarazo/fisiopatología , Resultado del Embarazo , Adulto , Encéfalo/patología , Encefalopatías Metabólicas Innatas/patología , Femenino , Humanos , Recién Nacido , Imagen por Resonancia Magnética , Embarazo
2.
Acta Clin Belg ; 61(1): 38-41, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16673616

RESUMEN

A case of purple urine bag syndrome, a rare condition in which the urinary catheter bag of chronically catheterised patients develops a discolouration, is reported. The excretion of indoxyl sulphate, an intermediate in the causal mechanism of this unusual phenomenon, was measured using Ehrlich's reagent and found not to be elevated in this 77 year-old man, when compared to elderly male control subjects.


Asunto(s)
Pigmentos Biológicos/metabolismo , Plásticos/metabolismo , Prostatectomía/efectos adversos , Cateterismo Urinario/efectos adversos , Incontinencia Urinaria/terapia , Anciano , Anciano de 80 o más Años , Bacterias/metabolismo , Estudios de Casos y Controles , Enfermedad Crónica , Color , Estudios de Seguimiento , Humanos , Masculino , Prostatectomía/métodos , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/cirugía , Medición de Riesgo , Síndrome , Cateterismo Urinario/métodos , Incontinencia Urinaria/etiología
4.
Biochem Biophys Res Commun ; 338(3): 1322-6, 2005 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-16274666

RESUMEN

This is the first report of a patient with aminoacylase I deficiency. High amounts of N-acetylated amino acids were detected by gas chromatography-mass spectrometry in the urine, including the derivatives of serine, glutamic acid, alanine, methionine, glycine, and smaller amounts of threonine, leucine, valine, and isoleucine. NMR spectroscopy confirmed these findings and, in addition, showed the presence of N-acetylglutamine and N-acetylasparagine. In EBV transformed lymphoblasts, aminoacylase I activity was deficient. Loss of activity was due to decreased amounts of aminoacylase I protein. The amount of mRNA for the aminoacylase I was decreased. DNA sequencing of the encoding ACY1 gene showed a homozygous c.1057 C>T transition, predicting a p.Arg353Cys substitution. Both parents were heterozygous for the mutation. The mutation was also detected in 5/161 controls. To exclude the possibility of a genetic polymorphism, protein expression studies were performed showing that the mutant protein had lost catalytic activity.


Asunto(s)
Amidohidrolasas/deficiencia , Amidohidrolasas/metabolismo , Errores Innatos del Metabolismo/enzimología , Amidohidrolasas/genética , Animales , Arginina/genética , Arginina/metabolismo , Células Cultivadas , Genoma Humano/genética , Humanos , Recién Nacido , Linfocitos/enzimología , Masculino , Errores Innatos del Metabolismo/genética , Errores Innatos del Metabolismo/orina , Mutación/genética , Péptido Hidrolasas/metabolismo , ARN Mensajero/genética
5.
J Med Genet ; 41(2): 120-4, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14757859

RESUMEN

In patients with mitochondrial encephalomyopathies an increasing number of causative gene defects have been detected. The number of identified pathogenic mitochondrial DNA mutations has largely increased over the past 15 years. Recently, much attention has turned to the investigation of nuclear oxidative phosphorylation (OXPHOS) gene defects. Within the OXPHOS defects, complex V deficiency is rarely found and, so far, these defects have only been attributed to mutations in the mitochondrial MTATP6 gene. Mutation analysis of the complete coding regions at the cDNA level of the nuclear ATP11, ATP12, ATPalpha, ATPbeta and ATPgamma genes and the mitochondrial MTATP6 and MTAT8 genes was undertaken in two unrelated patients. Blue Native polyacrylamide gel electrophoresis followed by catalytic staining had already documented their complex V decreased activity. Extensive molecular analysis of five nuclear and two mitochondrial genes revealed a mutation in the ATP12 assembly gene in one patient. This mutation is believed to be the cause of the impaired complex V activity. To our knowledge, this is the first report of a pathogenic mutation in a human nuclear encoded ATPase assembly gene.


Asunto(s)
Adenosina Trifosfatasas/deficiencia , Adenosina Trifosfatasas/genética , Proteínas Portadoras , Chaperoninas/genética , Proteínas de la Membrana/deficiencia , Proteínas de la Membrana/genética , Enfermedades Mitocondriales/genética , Mutación/genética , ATPasas de Translocación de Protón/genética , Proteínas de Saccharomyces cerevisiae/genética , Anomalías Múltiples/genética , Anomalías Múltiples/patología , Adenosina Trifosfatasas/fisiología , Secuencia de Aminoácidos/genética , Chaperoninas/química , Chaperoninas/fisiología , Consanguinidad , Resultado Fatal , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Proteínas de la Membrana/fisiología , Enfermedades Mitocondriales/diagnóstico , ATPasas de Translocación de Protón Mitocondriales , Chaperonas Moleculares , Datos de Secuencia Molecular , Mutación/fisiología , Fosforilación Oxidativa , ATPasas de Translocación de Protón/química , ATPasas de Translocación de Protón/fisiología , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/fisiología
6.
Acta Paediatr ; 92(7): 806-10, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12892159

RESUMEN

AIM: To establish reference values for disaccharidase activities in Belgian children and to compare enzyme activities with those of non-Belgian Caucasian children. METHODS: Data from Belgian children who had undergone endoscopic jejunal biopsies (1994-2000) for suspected malabsorption were reviewed. The patients were divided into three groups based on histology: (A) normal (n = 201), (B) moderate changes (n = 58) and (C) (sub)total atrophy (n = 14). The 95% reference limits for disaccharidase activities (U/g protein) were calculated for group A after exclusion of patients with a positive hydrogen breath test, a history of lactose intolerance or coeliac disease (final population: n = 151, 0.1-12 y). Values were compared with those of 34 non-Belgian Caucasian children with normal histology (28 of Mediterranean origin). RESULTS: The reference limits (90% confidence interval) were 86 (65-111)-423 (366-494) for maltase, 9 (6-12)-91 (78-122) for lactase and 24 (18-30)-155 (120-184) for sucrase. No gender-related differences in enzyme activities were found. Lactase levels showed a slight decrease with increasing age. Disaccharidase activities of children with histologically confirmed mucosal injury were significantly lower than those of children with normal histology: median values for groups A, B and C were 208, 181 and 96, respectively, for maltase, 40, 28 and 7, respectively, for lactase and 69, 54 and 25, respectively, for sucrase. Median disaccharidase activities in biopsies with normal histology were lower in non-Belgian children, the difference being only statistically significant for lactase, 33 versus 40. CONCLUSION: The reference values for Belgian children are well in line with other reported values from Caucasian children. Although enzyme activities are lower in children with histologically confirmed mucosal damage, they do not allow differentiation between histology groups. Lower lactase values were found in non-Belgian children.


Asunto(s)
Disacaridasas/metabolismo , Yeyuno/patología , Síndromes de Malabsorción/etnología , Síndromes de Malabsorción/enzimología , Atrofia/patología , Bélgica/epidemiología , Biopsia , Preescolar , Endoscopía Gastrointestinal , Etnicidad/estadística & datos numéricos , Femenino , Humanos , Lactante , Lactasa/metabolismo , Síndromes de Malabsorción/diagnóstico , Masculino , Valores de Referencia , Sacarasa/metabolismo , alfa-Glucosidasas/metabolismo
7.
Am J Med Genet A ; 120A(1): 13-8, 2003 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-12794685

RESUMEN

A homozygous mutation in the flavoprotein (Fp) gene associated with complex II deficiency was demonstrated in a patient with consanguineous parents. She succumbed at 5(1/2) months of age following a respiratory infection. The c1664G-->A transition detected, predicted the substitution of the small uncharged glycine at position 555 by glutamic acid. Her clinical course was at variance with the Leigh syndrome in three previously reported patients due to Fp gene mutations. In this proband, CRM for flavoprotein as well as iron-containing protein (Ip) was decreased, CRM for the entire complex II (130 kDa) being reduced even more. This observation prompts speculation of a labile interaction between Ip and Fp polypeptides and of a key role of the amino acid at position 555 in the interacting domain.


Asunto(s)
Núcleo Celular/metabolismo , Transporte de Electrón/genética , Flavoproteínas/genética , Glutamina/química , Glicina/química , Homocigoto , Mutación , Aminoácidos/química , Cardiomegalia/genética , Electroforesis en Gel de Poliacrilamida , Femenino , Fibroblastos/metabolismo , Ácido Glutámico/genética , Glicina/genética , Humanos , Lactante , Hierro/química , Modelos Moleculares , Músculo Esquelético/metabolismo , Oxígeno/metabolismo , Péptidos/química , Fosforilación , Estructura Terciaria de Proteína
8.
J Anal Toxicol ; 25(2): 77-80, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11300510

RESUMEN

In methanol intoxication, increased levels of the metabolite formate are associated with metabolic acidosis and an increased risk for ocular and neurological dysfunction. A simple method for plasma formate measurement by adaptation of a manual enzymatic assay to a Cobas Mira S analyzer is presented. Six microliters of sample is incubated for 5 min with buffer containing nicotinamide-adenine dinucleotide. Fifteen microliters of a suspension of formate dehydrogenase is then added. Absorbance at 340 nm is measured every 25 s. The NADH produced when formate is oxidized is stoichiometric to the amount of formate. The method is sensitive, reproducible, and specific and has a broad measurement range. The frozen reagents are stable for at least six months, so the described method can be applied to irregular and semi-urgent requests. A recent case is reported.


Asunto(s)
Formiato Deshidrogenasas/metabolismo , Formiatos/sangre , Metanol/metabolismo , Acidosis/diagnóstico , Acidosis/metabolismo , Adulto , Humanos , Indicadores y Reactivos , Masculino , Metanol/toxicidad , NAD/metabolismo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Clin Chem Lab Med ; 39(1): 20-4, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11256795

RESUMEN

The plasma concentration of glycerol, the backbone of triglycerides and the end product of triacylglycerol breakdown, is considered to reflect lipolysis in adipose tissue. We evaluated an automated enzymatic procedure for the measurement of glycerol in plasma. The assay was linear up to 250 micromol/l. The detection limit was 8 micromol/l. Recovery averaged 94% from spiked plasma and 104% from diluted plasma. An extensive precision study performed according to the guidelines of the National Committee for Clinical Laboratory Standards showed within-run coefficients of variation between 14.8% and 2.6% for concentrations ranging from 28 micromol/l to 164 micromol/l. The reference range for fasting healthy adult men was 14-69 micromol/l. Glycerol levels were significantly correlated with free fatty acid levels. This automated enzymatic method is rapid and reliable, and provides greater sensitivity or convenience than previously described procedures.


Asunto(s)
Química Clínica/métodos , Glicerol/sangre , Adulto , Bilirrubina/farmacología , Ácidos Grasos no Esterificados/metabolismo , Glicerol/farmacología , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Obstet Gynecol ; 97(1): 57-61, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11152908

RESUMEN

OBJECTIVE: To assess the influence of chronic active maternal smoking on cord blood amino acid and enzyme levels at term. METHODS: The concentrations of 24 free amino acids, total protein, and five enzymes were measured in samples of maternal and fetal cord venous plasma from 24 nonsmokers who were not exposed to tobacco smoke and 24 chronic smokers. Cotinine levels were also measured in maternal plasma to evaluate fetal tobacco exposure. The pregnancies were between 37 and 40 weeks' gestation, were uncomplicated, and were delivered vaginally. RESULTS: Fetal weight was significantly (P <.01) lower in the smokers than in controls. A positive significant (P <.001) correlation was found between maternal and umbilical venous cotinine concentrations. Significantly lower concentrations of aspartic acid (P <.01), hydroxyproline (P <.05), threonine (P <.005), alanine (P <.05), alpha-aminobutyric acid (P <.001), methionine (P <.05), tyrosine (P <.001), phenylalanine (P <.01), and lysine (P <.05) were found in the venous cord plasma of the smokers compared with nonsmokers. The fetomaternal ratios were similar in both groups. The umbilical plasma alkaline phosphatase activity was significantly (P <.01) lower in the smokers than in the controls. CONCLUSION: Chronic maternal smoking is associated with alterations of protein metabolism and enzyme activity in fetal cord blood. These may be secondary to irreversible changes in the cellular functions of the trophoblast and may contribute to fetal growth restriction.


Asunto(s)
Aminoácidos/análisis , Sangre Fetal/química , Fumar/fisiopatología , Adulto , Fosfatasa Alcalina/sangre , Cotinina/sangre , Femenino , Sangre Fetal/enzimología , Peso Fetal , Humanos , Masculino , Embarazo
11.
Am J Respir Crit Care Med ; 162(3 Pt 1): 1023-6, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10988124

RESUMEN

Currently, no reliable data are available on the volume or on the cellular content of pleural fluid in normal humans. In analogy with bronchoalveolar lavage (a technique enabling retrieval of small volumes of epithelial lining fluid from the lung), we developed a pleural lavage (PL) technique consisting of injection and retrieval of 150 ml of saline into the right pleural space, performed during a thoracoscopic sympathicolysis procedure in otherwise healthy subjects suffering from essential hyperhidrosis. With urea used as an endogenous marker of dilution, measured mean right-sided pleural fluid volume was 8.4 +/- 4.3 ml. In a subgroup of subjects, we confirmed that right- and left-sided pleural fluid volumes were similar. Expressed per kilogram of body mass, total pleural fluid volume in normal, nonsmoking humans is 0.26 +/- 0.1 ml/kg. Total cell count in the PL fluid of nonsmoking normal subjects yielded a median of 91 x 10(3) white blood cells (WBC) per milliliter of lavage fluid (interquartile range [IR] = 124 x 10(3) cells/ml). Taking into account a measured dilution factor of 18.86, the total WBC count in the original pleural fluid was 1,716 x 10(3) cells/ml. Differential cell counts yielded a predominance of macrophages (median: 75%; IR: 16%) and lymphocytes (median: 23%; IR: 18%). Mesothelial cells (median: 1%; IR: 2%), neutrophils (median: 0%; IR: 1%), and eosinophils (median: 0%; IR: 0%) were only marginally present. There were no significant differences between males and females or between right- and left-sided pleural fluid in total and differential cell counts. In contrast, in smokers a small but statistically significant increase in pleural fluid neutrophils (median: 1%; IR: 2%; p < 0.015) was observed. In conclusion, PL performed during thoracoscopy for sympathicolysis allowed for the first time determination of the volume and of the total and differential cell contents of the pleural fluid present in normal human pleura.


Asunto(s)
Derrame Pleural/citología , Adolescente , Adulto , Femenino , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Neutrófilos/inmunología , Valores de Referencia , Fumar/patología , Subgrupos de Linfocitos T/inmunología
12.
Obstet Gynecol ; 93(5 Pt 1): 680-3, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10912966

RESUMEN

OBJECTIVE: To assess the influence of active maternal smoking on fetal amino acid and enzyme levels in early pregnancy. METHODS: The concentrations of 23 free amino acids and total protein, and the activity levels of four enzymes were measured in samples of maternal and fetal plasma from nine nonsmokers who were not exposed to tobacco smoke and nine long-term, heavy smokers matched for gestational age. To determine fetal exposure to smoking, cotinine levels were measured in maternal and fetal plasma and fetal liver samples from both groups. The pregnancies were between 12 and 17 weeks' gestation. RESULTS: In women who smoke, the median cotinine concentrations were 156 mg/mL in maternal plasma and 89 ng/mL in fetal plasma, but only one fetal liver sample contained detectable cotinine. Significantly lower concentrations of serine, proline, alpha-aminobutyric acid, leucine, and arginine were found in smokers compared with nonsmokers, with the lowest in arginine. Fetal plasma amylase activity was significantly higher in smokers than controls. There were no differences in concentrations of other amino acids or activity levels of other enzymes in the two groups. CONCLUSION: Maternal smoking affected placental and fetal protein metabolism and enzyme activity from at least 12 weeks' gestation. That finding indicates that high levels of tobacco exposure in the first trimester might cause irreversible changes in the cellular functions of the villous trophoblastic barrier.


Asunto(s)
Aminoácidos/sangre , Enzimas/sangre , Sangre Fetal/enzimología , Fumar/efectos adversos , Contaminación por Humo de Tabaco/efectos adversos , Alanina Transaminasa/sangre , Amilasas/sangre , Aspartato Aminotransferasas/sangre , Femenino , Edad Gestacional , Humanos , Recién Nacido , Hígado/embriología , Hígado/enzimología , Pruebas de Función Hepática , Intercambio Materno-Fetal/efectos de los fármacos , Intercambio Materno-Fetal/fisiología , Embarazo , Fumar/sangre , gamma-Glutamiltransferasa/sangre
14.
Early Hum Dev ; 51(2): 159-69, 1998 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-9605468

RESUMEN

The trophoblast functions of nutrient transport and protein synthesis generate high concentrations of amino acids in the placenta and in fetal blood during the second half of pregnancy, but little is known about these metabolic processes in embryonic and early fetal periods. The aim of this study is to compare the distribution of amino acids inside the first trimester gestational sac. Free amino acid concentrations were measured in homogenates of placental villi, in samples of coelomic and amniotic fluid, and in the maternal serum from 17 normal pregnancies between 7 and 11 weeks of gestation. Significant positive relationships between maternal serum and placental tissue were found for 10 amino acids, indicating that active amino acid transport and accumulation by the human syncytiotrophoblast occurs as early as 7 weeks of gestation. The transplacental flux of most amino acid transport from maternal blood to the exocoelomic cavity was against a concentration gradient. The highest placental amino acid concentrations were found for taurine, glutamic acid, glycine and alanine. The amniotic fluid contained lower mean concentration of all amino acids than coelomic fluid and maternal serum. The concentration distribution of individual amino acids in coelomic and amniotic fluid were related indicating a passive transfer through the amniotic membrane. A coelomic-maternal gradient was observed in 19 out of 24 amino acids measured and positive correlations were found between maternal serum and coelomic fluid for concentrations of alpha-aminobutyric acid, tyrosine and histidine, suggesting that these amino acids are only partially retained and/or transferred more rapidly by the early placenta.


Asunto(s)
Aminoácidos/análisis , Edad Gestacional , Placenta/química , Alanina/análisis , Aminoácidos/sangre , Líquido Amniótico/química , Líquidos Corporales/química , Femenino , Ácido Glutámico/análisis , Glicina/análisis , Humanos , Embarazo , Primer Trimestre del Embarazo , Taurina/análisis , Distribución Tisular
15.
Eur J Clin Invest ; 27(3): 202-5, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9088855

RESUMEN

Essential hyperhidrosis (EH) is caused by a poorly understood overactivity of the sympathetic fibres passing through the upper dorsal sympathetic ganglia D2 and D3. These ganglia are also in the pathway of the sympathetic innervation of the heart and lungs. Therefore, although the predominant sympathetic neurotransmitter at the eccrine sweat glands is acetylcholine, the plasma concentration of noradrenaline (NA) (which is the main sympathetic neurotransmitter at the end organs including the heart and the lungs) may be elevated. Furthermore, as there are some indications for generalized sympathetic overactivity in EH, the plasma concentration of adrenaline (A) may also be elevated. Plasma levels of NA and A were therefore determined in 13 EH patients before and after thoracoscopic D2-D3 sympathicolysis (TS). Preoperative NA and A plasma levels were all within the normal limits used in our laboratory. After TS, mean NA plasma levels are significantly decreased, whereas mean A are unchanged. We conclude that sympathetic overactivity in EH is limited to the upper dorsal sympathetic ganglia and that some of the cardiovascular and pulmonary effects that are observed after TS may be associated with the decrease in NA.


Asunto(s)
Epinefrina/sangre , Ganglios Simpáticos/cirugía , Hiperhidrosis/sangre , Hiperhidrosis/cirugía , Norepinefrina/sangre , Simpatectomía/métodos , Adolescente , Adulto , Femenino , Ganglios Simpáticos/fisiopatología , Humanos , Hiperhidrosis/fisiopatología , Masculino , Persona de Mediana Edad , Toracoscopía
16.
JPEN J Parenter Enteral Nutr ; 21(1): 27-30, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9002081

RESUMEN

BACKGROUND: Hydrolysates are used in the treatment and prevention of cows milk protein allergy. Hydrolysis might alter the plasma level of amino acids. METHODS: Forty-five infants were included in a double-blind prospective study and were randomized in two groups: one receiving a whey predominant formula (n = 20) and the second group receiving a whey hydrolysate formula (n = 25). Weight and length gain was evaluated up to the age of 13 weeks, when blood was sampled for determination of fasting plasma amino acids. RESULTS: Four infants of the hydrolysate group dropped out because refusal to ingest the formula. Weight and length gain at 13 weeks of age were extremely comparable. Significant differences in plasma concentrations were observed for a number of nonessential and essential amino acids (p = .035 to .0001). Threonine and lysine were both higher in the hydrolysate group, and aspartic acid, cystine, methionine, tyrosine, phenylalanine, histidine, and arginine were lower in the hydrolysate group. CONCLUSIONS: These differences in plasma amino acid levels have to be regarded with care because all concentrations were within normal ranges, with the exception of threonine. Weight and length gain of the hydrolysate and the whey predominant formula were identical.


Asunto(s)
Aminoácidos/sangre , Alimentos Infantiles , Peso al Nacer , Método Doble Ciego , Humanos , Recién Nacido , Estudios Prospectivos , Distribución Aleatoria , Aumento de Peso
17.
Clin Chem ; 43(12): 2353-7, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9439454

RESUMEN

To investigate the effect of calibration with lyophilized calibrators on the interassay precision of glycohemoglobin (glyHb) measurements, we used an ion-exchange HPLC system equipped with a Pharmacia Mono S HR 5/5 column. Calibration of analytical runs substantially increased interassay variation (CV), from 1.7% to 4.4% and from 0.9% to 3.2% for control samples with low (6.5%) and high (14%) glyHb percentages, respectively. Standardization of glyHb results, though essential for interlaboratory comparisons, should not be done at the expense of assay precision, as may occur with thoughtless use of lyophilized calibrators. We therefore recommend the use of carefully determined conversion factors for standardization of glyHb results obtained with ion-exchange HPLC systems that are capable of excellent long-term interassay precision.


Asunto(s)
Hemoglobina Glucada/análisis , Calibración , Cromatografía Líquida de Alta Presión/métodos , Cromatografía por Intercambio Iónico , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Diabetes Res Clin Pract ; 34(2): 89-98, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9031811

RESUMEN

Diabetes mellitus is known to be associated with sodium retention. The aim of the present paper was to investigate the possible role of the renal dopaminergic system in the disturbed sodium homeostasis of Type 2 diabetic patients. The urinary dopamine excretion, which represents the local kidney production, was lower in Type 2 diabetic patients as compared to controls and decreased in insulin treated patients as compared to patients treated without insulin. Urinary dopamine excretion correlated positively with sodium excretion in non-insulin treated patients and in controls, but not in insulin treated patients. In contrast to findings in healthy volunteers, an intravenous sodium load failed to increase the dopamine excretion in Type 2 diabetic patients, despite similar increments in sodium excretion. A low-dose dopamine infusion caused significantly lower natriuretic responses in insulin treated Type 2 diabetic patients as compared to controls, but not in non-insulin treated patients. These findings suggest that Type 2 diabetic patients display a derangement of the renal dopaminergic system, which is accentuated by insulin treatment.


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Dopamina/fisiología , Natriuresis/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 2/orina , Dopamina/orina , Femenino , Homeostasis , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Distribución por Sexo , Sodio
19.
Eur J Clin Chem Clin Biochem ; 34(5): 449-53, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8790983

RESUMEN

We evaluated a homogenous immunoturbidimetric assay for haemoglobin A1c (Tina-quant Haemog bin A1c, Boehringer Mannheim, GmbH, Mannheim, Germany) adapted to a Cobas Mira S analyser (F. Hoffmann-La Roche & Co., Basel, Switzerland) and not requiring sample pretreatment. Between-day CV's determined over a 6 week period were 5.9% and 5.3% for mean haemoglobin A1c values of 5.4% and 17.0% of total haemoglobin respectively. The imprecision was higher than with an in-house ion-exchange high performance liquid chromatographic method. Bilirubin, triacylglycerols and the labile fraction of haemoglobin A1c did not interfere with the assay of haemoglobin A1c. Fetal haemoglobin is not recognized by the antibodies used. Results correlated well with those obtained by high performance liquid chromatography. In conclusion, the Tina-quant assay is not prone to common interferences and allows the rapid and automated determination of haemoglobin A1c on open photometric analysers.


Asunto(s)
Análisis Químico de la Sangre/métodos , Hemoglobina Glucada/análisis , Inmunoensayo/métodos , Nefelometría y Turbidimetría/métodos , Análisis Químico de la Sangre/instrumentación , Análisis Químico de la Sangre/estadística & datos numéricos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Líquida de Alta Presión/estadística & datos numéricos , Diabetes Mellitus/sangre , Estudios de Evaluación como Asunto , Hemoglobina Fetal/análisis , Humanos , Inmunoensayo/instrumentación , Inmunoensayo/estadística & datos numéricos , Nefelometría y Turbidimetría/instrumentación , Nefelometría y Turbidimetría/estadística & datos numéricos
20.
Acta Clin Belg ; 51(5): 320-7, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8950839

RESUMEN

The authors report a case of unsuspected fetal storage disorder initially diagnosed by placental examination performed because of a transient ascites at 28 weeks of gestation. At birth mild dysmorphic features and gradual neurological deterioration were observed. Highly elevated alkaline phosphatase levels were repeatedly noticed. Deficiency of beta-galactosidase was documented confirming GM1 gangliosidosis. Previous reports described the placental pathology after positive prenatal diagnoses of lysosomal diseases. In the present case, the postnatal diagnosis was made in view of the placental pathologic findings. Our observation indicates the need for thorough investigations in hydrops fetalis, in search for metabolic diseases.


Asunto(s)
Fosfatasa Alcalina/sangre , Gangliosidosis GM1/sangre , Hidropesía Fetal/sangre , Cromatografía en Capa Delgada , Diagnóstico Diferencial , Femenino , Gangliosidosis GM1/patología , Humanos , Recién Nacido , Oligosacáridos/orina , Placenta/patología , beta-Galactosidasa/deficiencia
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