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Biomedical subjects

G A van den Berg

Publications and source records attributed to G A van den Berg.

At least 19 recordsLinked to original sources
PubMed2003

Enteropathy-associated T-cell lymphoma presenting with eosinophilia.

Hypereosinophilia can be related to various diseases; when it occurs without an obvious cause it is called idiopathic hypereosinophilic syndrome (IHES). We describe a patient with increasing eosinophilia, which in spite of extensive diagnostic procedures initially remained unexplained. However, during follow-up it became apparent that this patient had a lethal enteropathy-associated T lymphoma (EATL) causing the hypereosinophilia.

Aged↗
PubMed2001

Dredging-related mobilisation of trace metals: a case study in The Netherlands.

Mobilisation of contaminants is an important issue in environmental risk assessment of dredging projects. This study has aimed at identifying the effects of dredging on mobilisation of trace metals (Zn, Cu, Cd and Pb). The intensities and time scales of trace metal mobilisation were investigated during an experimental dredging project conducted under field conditions. The loss of contaminated dredge spoil is mainly reflected by increasing levels of trace metals in the suspended matter, dissolved trace metal concentrations in the water column are not significantly influenced by the dredging activities. This indicates a strong binding mechanism of trace metals to the solid phase or a fast redistribution over sorptive phases in response to oxidation of e.g. trace metal sulphides. Given the differences in levels of reactive phases (Mn, Fe, sulphides and organic matter) between the riverine suspended matter and the sediments, changes in the levels of these parameters in the suspended matter upon dredging may give information on the processes influencing the behaviour of trace metals and on the potential loss of sediment during dredging operations. Therefore, we recommend to routinely measure these parameters in studies on contaminant behaviour related to dredging activities.

Cadmium↗
PubMed1998

Elevated homocysteine levels indicate suboptimal folate status in pediatric sickle cell patients.

We investigated whether pediatric patients with sickle cell disease (SCD) (9 +/- 4 years; 27 homozygous SCD [HbSS]; 19 sickle-C disease [HbSC]) have different folate status compared with age-, sex-, and race-matched normal hemoglobin (HbAA) controls (n = 20), and whether their folate status can be improved by folate supplementation. The patients were supplemented with vitamins B6 and B12 during one week and with folate during the following week. Circulating folate, homocysteine, vitamin B6 and vitamin B12 levels were measured at baseline (patients and controls), after one week and after two weeks (patients). The patients had similar folate, vitamin B6, and vitamin B12, but higher homocysteine levels compared with HbAA controls (12.7 +/- 4.5 vs. 10.9 +/- 3.5 micromol/l; P = 0.04). Vitamin B6 and B12 supplementation did not change their homocysteine levels, but folate supplementation caused a 53% reduction (to 5.7 +/- 1.6). We conclude that patients with SCD have adequate vitamin B6 and B12 status, but suboptimal folate status, leading to elevated plasma homocysteine levels. They may therefore benefit from folate supplementation to reduce their high risk for endothelial damage.

Adolescent↗
PubMed1995

Investigation of polyamine metabolism by high-performance liquid chromatographic and gas chromatographic profiling methods.

Measurements of polyamines, polyamine conjugates and their metabolites in tissues, cells and extracellular fluids are used in biochemistry, (micro)biology, oncology and parasitology. Decarboxylation of ornithine yields putrescine. Aminopropylation of putrescine yields spermidine, and aminopropylation of spermidine yields spermine. Spermidine and spermine are retroconverted to putrescine and spermidine, respectively, by initial N-acetylation and subsequent polyamine oxidation. The intermediate N-acetylputrescine, N1-acetylspermidine and N8-acetylspermidine are the major urinary N-acetylpolyamines. Polyamines and N-acetylpolyamines are terminally degraded to non-alpha-amino acid metabolites by oxidative deamination and aldehyde dehydrogenation. Chromatography with on-line detection is the most commonly applied profiling method for polyamines, N-acetylpolyamines and their non-alpha-amino acid metabolites. Cation-exchange and reversed-phase high-performance liquid chromatography require pre- or post-column derivatisation, followed by UV-Vis spectrophotometric or fluorimetric detection. Isolation and derivatisation precedes gas chromatography with flame-ionisation, nitrogen-phosphorus, electron-capture or mass spectrometric detection. High-performance liquid chromatography and gas chromatography of polyamines are not competitive techniques, but rather supplementary.

Chromatography, Gas↗
PubMed1992

Screening cord blood for hemoglobinopathies and thalassemia by HPLC.

We evaluated the use of an HPLC method for screening hemoglobins in cord blood. We studied the genotype frequencies of the structural hemoglobin variants HbS and HbC and the synthesis variants alpha- and beta(+)-thalassemia in babies born on Curaçao. During three months, 67.2% of all (748) newborns were screened: 122 (24.3%) had an abnormal hemoglobin pattern, of which 53 (43.4%) had a hemoglobinopathy (HbS or HbC), 64 (52.2%) had alpha-thalassemia (HbBarts greater than 0.5%, corresponding to heterozygous or homozygous alpha-thalassemia-2), and 5 (4.1%) had a hemoglobinopathy plus alpha-thalassemia. None of the newborns with heterozygous HbS and HbC had concomitant beta(+)-thalassemia. The population genotype frequency of heterozygous alpha-thalassemia-2 was calculated to be 30.7%. The data are in excellent agreement with those previously established for the adult population and those available from the black population in the United States and Jamaica. Based on the HPLC results, we estimate that 67.1% of newborns with heterozygous alpha-thalassemia-2 remain undetected. A coincidental finding was a relation between demonstrable alpha-thalassemia and short gestation. Because of its superior separating power and high sensitivity for quantifying relatively low percentages of hemoglobins in the presence of HbF0, the HPLC method was preeminently suitable for screening cord-blood samples.

Chromatography, High Pressure Liquid↗
PubMed1991

Gas chromatographic determination of N-acetylisoputreanine-gamma-lactam, a unique catabolite of N1-acetylspermidine.

A capillary gas chromatographic method with nitrogen-phosphorus detection for the determination of N-acetylisoputreanine-gamma-lactam (acisoga) in urine is described. The method was validated by comparing the results with those given by an isotope dilution mass fragmentographic method. Making use of specific inhibitors for copper-dependent amine oxidase and polyamine oxidase in rats, it was demonstrated that acisoga is formed by oxidative deamination of N1-acetylspermidine by the former enzyme. Moreover, acisoga is not a substrate for pig liver polyamine oxidase. Increased concentrations of acisoga, relative to N1-acetylspermidine, in urines of patients with non-Hodgkin's lymphoma indicated that this conversion diminishes the sensitivity of N1-acetylspermidine as a marker for (tumour) cell death.

Animals↗
PubMed1990

Urinary polyamine and metabolite excretion by children with Zellweger's syndrome.

In order to investigate whether, due to a lack of peroxisomes, polyamine degradation is altered in patients with the cerebro-hepato-renal syndrome of Zellweger, we determined total, free and acetylated polyamines and some of their catabolites in urines of six patients and age-matched healthy children. The normal polyamine excretion patterns of the patients, compared to the control group, suggest that either the intracellular localisation of the polyamine degrading enzyme, polyamine oxidase, is not exclusively limited to peroxisomes or that the enzyme is located in the peroxisomal matrix.

Amino Acids, Diamino↗
PubMed1989

Microbial flora in the gastrointestinal tract abolishes cytostatic effects of alpha-difluoromethylornithine in vivo.

Although treatment with the ornithine decarboxylase inhibitor alpha-difluoromethylornithine (DFMO) leads to depletion of intracellular polyamines and to related growth inhibition in vitro, its cytostatic effects in vivo are disappointing. This may be due to abolition of DFMO-induced growth inhibition by polyamines released during normal body cell turnover, to dietary polyamines, or to putrescine synthesized by the microbial flora in the GI tract. We studied selectively (aerobic) and totally (aerobic + anaerobic) GI tract-decontaminated LI210-bearing mice fed with 3 types of diet differing in their polyamine and carbohydrate residue contents and treated with combinations of intraperitoneal DFMO and oral deuterium-labelled putrescine. Our data show that, irrespective of diet type, total decontamination markedly potentiates the moderate tumor growth inhibition that is caused by DFMO alone. During total decontamination, growth-inhibited L1210 cells accumulate in the G0/G1 phase of the cell cycle. Although orally administered deuterium-labelled putrescine gave rise to deuterium labelling of L1210 putrescine, spermidine and spermine, the polyamine levels in our diets played only a minor role.

Animals↗
PubMed1989

Microbial influences on urinary polyamine excretion.

We determined diamines, polyamines, their monoacetylated conjugates and some of their catabolites in urines of healthy persons during decontamination of the gastrointestinal tract and patients with urinary tract infections. The compounds were also measured after in vitro incubation of urines from healthy persons and patients. During decontamination the urinary excretion of total putrescine decreased by a small amount. This fall was for the greater part accountable to monoacetylated putrescine. Free putrescine levels were increased in urines of patients with urinary tract infections, decreased after therapy, and increased after incubation of the pretherapeutical samples. Total cadaverine decreased during decontamination and increased during recontamination. The changes were partly accountable to monoacetylated cadaverine. Free cadaverine levels of patients with urinary tract infections were normal and did not change after therapy. These data show that, under normal conditions, a small part of monoacetylated putrescine and a considerable part of monoacetylated cadaverine originate from the gastrointestinal tract, and that urinary tract infections lead to an increase of free putrescine. The microbial synthesis of putrescine in the gastrointestinal- and urinary tracts, should therefore be taken into account for the interpretation of urinary putrescine levels as a parameter for body cell turnover.

Adult↗
PubMed1989

Catecholamine metabolism during additional administration of DL-threo-3,4-dihydroxyphenylserine to patients with Parkinson's disease.

DL-threo-3,4-dihydroxyphenylserine (DL-threo-DOPS) was administered during 10 days to 4 patients with longstanding Parkinson's disease in addition to their treatment with L-3,4-dihydroxyphenyl-L-alanine (L-DOPA)-carbidopa (Sinemet). All patients tended to improve in their symptoms freezing, all day life activity and mood. There were no improvements in rigidity, tremor, and akinesia (in general). During the DL-threo-DOPS-treatment cerebrospinal fluid (CSF), serum and urine concentrations of catecholamines were measured. The results show that DL-threo-DOPS is transported to the brain and CSF in a way comparable with L-DOPA. However, no measurable increase of 3-methoxy-4-hydroxyphenylethyleneglycol (MOPEG) in CSF could be demonstrated. This suggests that the synthesis of noradrenaline from DL-threo-DOPS in the brain is doubtful. In addition measurements in urine reveals that at the dose used Sinemet prevents peripheral decarboxylation of DL-threo-DOPS into noradrenaline. Other possible metabolic pathways of DL-threo-DOPS are discussed.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1988

Gestational-age-dependent concentrations of polyamines, their conjugates and metabolites in urine and amniotic fluid.

The metabolism and fate of polyamines during cell proliferation, differentiation, and cell loss were investigated by measuring the concentration of polyamines, their conjugates and some of their metabolites in amniotic fluid of 24 subjects, and in urine of 85 women during pregnancy. The increase of putrescine and spermine in acid-hydrolysed urines during pregnancy appeared to be almost completely due to increases in monoacetylated putrescine and N1,N12 diacetylated spermine, respectively. The latter two were the quantitatively most important polyamines in amniotic fluid. In urine, monoacetylated putrescine showed the highest levels at the end of pregnancy, whereas N1,N12 diacetylated spermine reached the highest values at about 32 weeks gestation. It was impossible to establish whether extracellular monoacetylated putrescine is linked either to cell growth or cell loss. The appearance of N1,N12 diacetylated spermine is probably due to cell loss and dependent on the degree of differentiation during fetal development. The decline and eventual disappearance of urinary N1,N12 diacetylated spermine during the first 2 years after birth may be coherent with maturation of the FAD-dependent polyamine oxidase activity.

Amniotic Fluid↗
PubMed1987

Determination of polyamines and metabolites in cerebrospinal fluid by isotope dilution mass fragmentography, and a clinical application.

Capillary gas chromatography and mass fragmentography was used to determine simultaneously 1,3-diaminopropane, putrescine, cadaverine, spermidine, spermine, isoputreanine and putreanine in cerebrospinal fluid. After addition of deuterium labelled analogs and acid hydrolysis, the compounds were isolated by adsorption onto silica and converted into their N-heptafluorobutyryl-methylesters. Quality control data and an application of the method are given. A patient harbouring an astrocytoma was monitored during chemotherapeutic treatment.

Astrocytoma↗
PubMed1987

Urinary polyamines and their metabolites during new combination chemotherapeutic treatments of high grade non-Hodgkin lymphoma.

Nineteen patients with non-Hodgkin lymphoma of unfavourable histology (15 high grade and 4 intermediate grade) were treated with two new combination chemotherapeutic schemes. Except for one all were partial (8) or complete (10) responders to treatment. Polyamines were measured in every spontaneously voided urine sample. Pretherapeutically all (11) stage III and IV patients had borderline or increased urinary putrescine (Pu) and sum of isoputreanine, spermidine and spermine (sigma Isoputr,Sd,Sp), except for the non-responder. Except for one, all (8) stage I and II patients had normal urinary Pu and sigma Isoputr,Sd,Sp. Posttherapeutically patients with pretherapeutically increased sigma Isoputr,Sd,Sp returned to normal (5), borderline (2), or slightly increased (3) levels. The post-therapeutic achievement of normal or borderline sigma Isoputr,Sd,Sp was not necessarily connected with accomplishment of complete remission. From the start of therapy until clinical restaging, partially or completely responding stage III and IV patients excreted 5-234 mmol sigma Isoputr,Sd,Sp per mol of creatinine above the mean normal value plus 2 SD. For stage I and II patients and the clinical non-responder this parameter amounted to 0-5 mmol/mol of creatinine. Peaks in urinary Pu and sigma Isoputr,Sd,Sp follow-up curves were related in time to the administration of chemotherapeutics. For responding stage III and IV patients the rate of the decrease of sigma Isoputr,Sd,Sp levels paralleled the clinically observed rate of tumour load reduction. This study suggests that notably for non-Hodgkin lymphoma patients with high tumour loads the constant monitoring of polyamines can provide information on pretherapeutic spontaneous tumour cell loss, the efficacy of chemotherapeutic combinations, the kinetics-, and (within certain limitations) the extent of therapeutically induced tumour cell death.

Adolescent↗
PubMed1987

Determination of polyamines in human erythrocytes by capillary gas chromatography with nitrogen-phosphorus detection.

A capillary gas chromatographic method with nitrogen-phosphorus detection is used to determine simultaneously 1,3-diaminopropane, putrescine, cadaverine, spermidine and spermine in human erythrocytes. The compounds are isolated by adsorption on silica and converted into their heptafluorobutyryl derivatives. We give quality-control data and (age-dependent) normal values for 48 apparently healthy controls.

Adult↗
PubMed1986

Determination of N-(3-acetamidopropyl)pyrrolidin-2-one, a metabolite of spermidine, in urine by isotope dilution mass fragmentography.

A capillary gas chromatographic method with mass spectrometric detection for the determination of N-(3-acetamidopropyl)pyrrolidin-2-one, the monoacetyl conjugate of isoputreanine-gamma-lactam, in urine has been developed. Using a quantification based on stable isotope dilution mass fragmentography, age-dependent normal values for the urinary excretion of N-(3-acetamidopropyl)pyrrolidin-2-one by 44 apparently healthy control subjects were determined. Quality control data and normal values for 27 adults are given. The method was applied to the monitoring of the chemotherapeutic treatment of two patients with high-grade non-Hodgkin lymphoma.

Adolescent↗
PubMed1986

Determination of pipecolic acid in urine and plasma by isotope dilution mass fragmentography.

A capillary gas chromatographic method with mass spectrometric detection for the determination of pipecolic acid in urine and plasma (or serum) has been developed. Using a quantification based on stable isotope dilution mass fragmentography the concentration of pipecolic acid was determined in urines of 34 healthy children and 8 patients with Zellweger's syndrome. The urinary pipecolic acid excretion of healthy infants decreases with age. Its concentration in urines of patients with Zellweger's syndrome was not consistently elevated. Normal values for pipecolic acid in plasma were established for 19 healthy children. Pipecolic acid concentrations in 47 urine samples (range 0.02-228.3 mmol/mol of creatinine) and 6 serum samples of Zellweger patients after oral loading with DL-pipecolic acid (range 65-1334 mumol/l) were found to correlate satisfactorily with the results obtained by an amino acid analyzer method. The major advantage of the presented method over the amino acid analyzer method concerns its greater sensitivity and its much shorter analysis time.

Abnormalities, Multiple↗
PubMed1986

Simultaneous gas-chromatographic determination of free and acetyl-conjugated polyamines in urine.

A capillary gas-chromatographic method with nitrogen-phosphorus detection is used to determine simultaneously urinary 1,3-diaminopropane, monoacetyl-1,3-diaminopropane, putrescine, monoacetylputrescine, cadaverine, monoacetylcadaverine, spermidine, N1-acetylspermidine, N beta-acetylspermidine, spermine, N1-acetylspermine, isoputreanine, N-(3-aminopropyl)pyrrolidin-2-one, and putreanine. The compounds are isolated by adsorption onto silica and converted into their methyl-heptafluorobutyryl derivatives. We give quality-control data and age-dependent "normal" values for urinary excretion of these analytes from 51 apparently healthy control subjects. Normal values for 31 adults are compared with those reported in the literature. Monoacetyl-1,3-diaminopropane and N1-acetylspermine are identified by mass fragmentography. We applied the method to monitor chemotherapeutic treatment of a patient with advanced non-Hodgkin's lymphoma; we identified by mass spectrometry N1,N12-diacetylspermine in this patient's urine.

Acetylation↗