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F A Muskiet

Publications and source records attributed to F A Muskiet.

At least 19 recordsLinked to original sources
PubMed2001

Effect of three low-dose fish oil supplements, administered during pregnancy, on neonatal long-chain polyunsaturated fatty acid status at birth.

Adequate long-chain polyunsaturated fatty acid (LCP) status during pregnancy is important. We studied the effect of three low-dose fish oil supplements, administered during uncomplicated pregnancy, on neonatal LCP status at term delivery. Supplements were administered from the second trimester to delivery, either as fish oil capsules ("fish-1": 336 mg LCPomega3, n=15; and "fish-3": 1,008 mg LCPomega3, n=20) or milk-based supplement ("Mum": 528 mg LCPomega3, n=24). Fifty-seven untreated women served as controls. Fatty acids of umbilical veins (UV) and arteries (UA) were measured. The fish-1 group showed no differences, compared to controls. The Mum group had higher 20:5omega3, 22:5omega3, 22:6omega3, LCPomega3 and 22:6omega3/22:5omega6 in UV and UA. The fish-3 group had higher 22:5omega3 and 22:6omega3 (UA), LCPomega3 and 22:6omega3/22:5omega6 (UV and UA) and 20:3omega6 (UV). A 500-1000 mg daily LCPomega3 supplement, taken either as a milk-based supplement or fish oil capsules, effectively increases fetal LCPomega3 status, without affecting LCPomega6 status.

Adult↗
PubMed2001

Influence of vitamin-optimized plasma homocysteine cutoff values on the prevalence of hyperhomocysteinemia in healthy adults.

BACKGROUND: Hyperhomocysteinemia is a cardiovascular disease (CVD) risk factor. We determined plasma homocysteine (Hcy) reference values at optimized vitamin status and investigated their influence on the prevalence of hyperhomocysteinemia in healthy adults. Results were compared with those obtained using European Concerted Action Project (ECAP) cutoff values. METHODS: Healthy adults (n = 101) received folic acid (5 mg/day) and vitamin B(12) (1 mg/day) for 2 weeks and the same dosages of folic acid and vitamin B(12) plus vitamin B(6) (1 mg. kg(-1). day(-1)) during the following 2 weeks. Hcy concentrations, both fasting and 6-h post-methionine load, were determined at baseline and after 4 weeks. RESULTS: Baseline (4 weeks) fasting and 6-h postload Hcy reference values were 4.7-14.6 (4.1-9.3) and 18.8-49.7 (12.9-35.1) micromol/L, respectively. Mean fasting and 6-h postload Hcy decreased after 4 weeks of vitamin supplementation by 3.5 micromol/L (33.5%) and 8.5 micromol/L (26.3%), respectively. The percentages of subjects exhibiting significant decreases in fasting Hcy following vitamin supplementation were 88% (all subjects), 92% (non-vitamin users), and 72% (vitamin users). The prevalences of hyperhomocysteinemia with use of ECAP cutoff values were 29% for all groups, 29% for men, 27% for premenopausal women, and 53% for postmenopausal women. With vitamin-optimized cutoff values, prevalences were 58%, 58%, 76%, and 89%, respectively. Use of vitamin-optimized cutoff values increased the diagnostic value of fasting Hcy and decreased that of a 6-h postload Hcy compared with use of ECAP cutoff values. CONCLUSIONS: Use of vitamin-optimized cutoff values gives rise to high hyperhomocysteinemia pretest probabilities in the general population and, therefore, precludes any meaningful role for Hcy testing. Future demonstration of a beneficial effect of decreasing Hcy on CVD risk would justify use of vitamin-optimized cutoff values for assessment of CVD risk.

Adolescent↗
PubMed2000

Clinical chemistry of serotonin and metabolites.

Analyses of serotonin and other 5-hydroxyindoles, such as its precursor 5-hydroxytryptophan and major metabolite 5-hydroxyindoleacetic acid (5-HIAA), are indispensable for the elucidation of their (patho)physiological roles. In clinical chemistry attention is mainly focused on the diagnosis and follow-up of carcinoid tumours. For this most laboratories routinely measure urinary 5-HIAA. More recently, measurements of serotonin in platelets and urine have been advocated. Platelet serotonin may be the most sensitive indole marker for the detection of carcinoid tumours that secrete only small amounts of serotonin and/or its precursor 5-hydroxytryptophan. Although several chromatographic techniques have emerged for the analysis of tryptophan-related indoles, HPLC with either electrochemical or fluorometric detection have become the methods of choice for their quantification. HPLC-based methods combine selectivity, sensitivity and high precision, and enable the simultaneous investigation of several metabolically related indoles. This review aims to place the analysis of indoles in biological matrices in a biochemical, physiological and clinical perspective and highlights several important steps in their chromatographic analysis and quantification.

Humans↗
PubMed2000

Vitamin D(3) and vitamin K(1) supplementation of Dutch postmenopausal women with normal and low bone mineral densities: effects on serum 25-hydroxyvitamin D and carboxylated osteocalcin.

OBJECTIVE: Improvement of vitamin D and K status of about 60 -y-old postmenopausal Dutch women. DESIGN: In a randomized study postmenopausal women with normal (T-score >-1; n=96) and low (T-score< or =-1; n=45) bone mineral density (BMD) of the lumbar spine, were supplemented with 350-400 IU vitamin D(3), 80 microg vitamins K(1) vitamins K(1)+D(3), or placebo for 1 y. Serum 25-hydroxyvitamin D [25(OH)D] and percentage carboxylated osteocalcin (%carbOC) were measured at baseline and after 3, 6 and 12 months. RESULTS: Baseline %carbOC of the entire study population was positively correlated with BMD of the lumbar spine and femoral neck. Correspondingly, women with low BMD had lower %carbOC at baseline than women with normal BMD but this difference disappeared after 1 y of supplementation with vitamin K(1) ((mean+/-s.d.) 68+/-11% (95% CI, 64. 5-71.2%) vs 72+/-6% (95% CI, 70.1-72.9%), respectively). One year of supplementation with vitamin D(3) showed maximum increases in 25(OH)D of 33+/-29% (95% CI, 24.8-41.8%) and 68+/-58% (95% CI, 50.1-84.6%) in women with normal and low BMD, respectively. During winter, however, a 29% decline in maximum 25(OH)D levels was not prevented in women with low BMD. CONCLUSION: Daily supplementation of Dutch postmenopausal women with >400 IU vitamin D(3) is indicated to prevent a winter decline in 25(OH)D and to control serum parathyroid hormone levels. Daily supplementation with 80 microg vitamin K(1) seems to be necessary to reach premenopausal %carbOC levels. A stimulatory effect of calcium and/or vitamin D on %carbOC cannot be excluded. European Journal of Clinical Nutrition (2000) 54, 626-631.

Aged↗
PubMed2000

Associations of alpha-linolenic acid and linoleic acid with risk factors for coronary heart disease.

BACKGROUND: Prevention of coronary heart disease (CHD) in high-risk subjects. OBJECTIVE: To investigate the associations of dietary intake of alpha-linolenic acid (ALA) and linoleic acid (LA) as assessed by food frequency questionnaire and in the plasma cholesteryl ester (CE), with CHD risk factors. DESIGN: Baseline data of a double-blind, randomized placebo-controlled trial. Subjects have hypercholesterolemia (6.0-8.0 mmol/l) and at least two other CHD risk factors (n=266). RESULTS: The reported dietary ALA and LA intakes and the LA/ALA ratio were associated with the contents in the CE (r=0.37, r=0.21, and r=0.42, respectively; P<0.01). In multivariate analysis, CE ALA was inversely associated with diastolic blood pressure (r=-0.13; P<0.05) and positively with serum triacylglycerol (r=0.13; P<0.05), and CE LA was inversely associated with serum triacylglycerol (r=-0.32; P<0.01). The CE LA/ALA ratio was strongly inversely associated with CE ALA (r=-0.95; P<0.01). In the lowest quintile of CE ALA, mean dietary intake was 0.4 energy % ALA (1.2 g/day), 8.4 energy % LA and an LA/ALA ratio of 21, and in the highest quintile 0.6 energy % ALA (1.7 g/day), 6.8 energy % LA and 12 (ratio). In the lowest quintile of CE ALA the diastolic blood pressure was 4 mm Hg lower (P trend<0.05), and the serum triacylglycerol 0.3 mmol/l higher (P trend NS) when compared with the top quintile. CONCLUSIONS: In a CHD high-risk population with LA-rich background diet, these cross-sectional data suggest that replacing LA in the diet by ALA may decrease diastolic blood pressure, and may increase serum triacylglycerol concentration.

Adult↗
PubMed2000

Effect of supplementation of arachidonic acid (AA) or a combination of AA plus docosahexaenoic acid on breastmilk fatty acid composition.

We investigated whether supplementation with arachidonic acid (20:4 omega 6; AA), or a combination of AA and docosahexaenoic acid (22:6 omega 3; DHA) would affect human milk polyunsaturated fatty acid (PUFA) composition. Ten women were daily supplemented with 300 mg AA, eight with 300 mg AA, 110 mg eicosapentaenoic acid (20:5 omega 3; EPA) and 400 mg DHA, for one week and eight women served as unsupplemented controls. Milk samples were collected on days 0, 1 and 7. The fatty acid composition of the milk was analyzed by capillary gas chromatography with flame ionisation detection. Supplementation with AA alone had no effect on breastmilk AA, but tended to reduce EPA and DHA levels. Administration of a combination of AA, EPA and DHA tended to increase both milk AA and long chain PUFA (LCPUFA)omega 3 content. A larger simultaneous increase of milk AA, DHA and EPA than observed in the present study can probably be accomplished by the use of a combination of a lower LCPUFA omega 6/LCPUFA omega 3 ratio and higher AA, EPA and DHA dosages.

Adult↗
PubMed2000

Polyunsaturated fatty acid status of Dutch vegans and omnivores.

We compared the polyunsaturated fatty acid (PUFA) status of Dutch vegans and omnivores to investigate whether disparities can be explained by different diets and long chain PUFA (LCP) synthesis rates. Dietary intakes and fatty acid compositions of erythrocytes (RBC), platelets (PLT), plasma cholesterol esters (CE) and plasma triglycerides (TG) of 12 strict vegans and 15 age- and sex-matched omnivores were determined. Vegans had higher omega 6 (CE, TG), 18:2 omega 6 (RBC, CE, TG), 18:3 omega 6 (TG), 20:3 omega 6 (TG), 22:4 omega 6 (TG), 22:5 omega 3 (RBC, PLT), 22:5 omega 3/22:6 omega 3 (RBC, PLT) and 22:5 omega 6/22:6 omega 3 (RBC, PLT), and lower 22:4 omega 6 (RBC, PLT), 22:4 omega 6/22:5 omega 6 (RBC, PLT), omega 3 (CE), LCP omega 3 (CE, TG), 20:5 omega 3 (RBC, PLT, CE), 22:5 omega 3 (TG) and 22:6 omega 3 (all compartments). Vegans had lower 20:4 omega 6 (TG) after normalization of PUFA to 100%, and normalization of eicosanoid precursors to 100% revealed similar 20:4 omega 6 (all), higher 20:3 omega 6 (TG) and lower 20:5 omega 3 (all). High omega 6 (notably 18:2 omega 6) and low omega 3 (notably 20:5 omega 3, 22:6 omega 3) status in Dutch vegans derives from low dietary LCP omega 3 and 18:3 omega 3/18:2 omega 6 ratio. Higher 18:3 omega 6 and 20:3 omega 6 in their TG may reflect higher hepatic 20:4 omega 6 production rate, whereas higher 20:4 omega 6 and 22:4 omega 6 in omnivores indicates 20:4 omega 6 intake from meat.

Adult↗
PubMed2000

Short-term supplementation of low-dose gamma-linolenic acid (GLA), alpha-linolenic acid (ALA), or GLA plus ALA does not augment LCP omega 3 status of Dutch vegans to an appreciable extent.

Vegans do not consume meat and fish and have therefore low intakes of long chain polyunsaturated fatty acids (LCP). They may consequently have little negative feedback inhibition from dietary LCP on conversion of alpha -linolenic acid (ALA) to the LCP omega 3 eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. We investigated whether supplementation of nine apparently healthy vegans with 2.01 g ALA (4 ml linseed oil), 1.17 g gamma-linolenic acid (GLA) (6 ml borage oil) or their combination increases the LCP omega 3 contents of erythrocytes (RBC) and platelets (PLT), and of plasma phospholipids (PL), cholesterol esters (CE) and triglycerides (TG). The supplements changed the dietary LA/ALA ratio (in g/g) from about 13.7 (baseline) to 6.8 (linseed oil), 14.3 (borage oil) and 6.4 (linseed + borage oil), respectively. ALA or GLA given as single supplements did not increase LCP omega 3 status, but their combination augmented LCP omega 3 (in CE) and EPA (in fasting TG) to a statistically significant, but nevertheless negligible, extent. We conclude that negative feedback inhibition by dietary LCP, if any, does not play an important role in the inability to augment notably DHA status by dietary ALA. The reach of a DHA plateau already at low dietary ALA intakes suggests that dietary DHA causes a non-functional DHA surplus, or is, alternatively, important for maintaining DHA status at a functionally relevant level.

Adult↗
PubMed2000

Mineral, amino acid, and hormonal composition of chicken eggshell powder and the evaluation of its use in human nutrition.

Chicken eggshell powder (ESP) might be an attractive source of Ca for human nutrition. To study its nutritional value, we analyzed minerals, amino acids, and hormones in commercially available Slovakian ESP. The mineral composition was compared with three Dutch ESP samples that differed in feed and housing, a Japanese ESP, refined CaCO3, and an oyster shell supplement. Chicken eggshell powder contains high levels of Ca (mean +/- SD/g EPS: 401+/-7.2 mg) and Sr (372+/-161 microg) when compared with recommended or estimated daily intakes for humans 51 to 70 yr of age. Levels of potentially toxic Pb, Al, Cd, and Hg were very low as were levels of V, B, Fe, Zn, P, Mg, N, F, Se, Cu, and Cr. Large differences in the levels of F, Se, Cu, Cr, and Sr in the Dutch and Slovakian ESP indicated a strong influence of feed and environment. The small protein fraction of ESP contains high levels of Gly and Arg. Furthermore, small amounts of transforming growth factor-beta1 (0.75 to 7.28 ng/g ESP), calcitonin (10 to 25 ng/g ESP), and progesterone (0.30 to 0.33 ng/g ESP) were detected. Estradiol-17beta and calcitriol were below the detection limit of the methods used. Compared with ESP, refined CaCO3 was found to contain increased levels of Cd, and the oyster shell supplement showed increased levels of Al and Cd. Therefore, ESP seems to have a beneficial composition with about 39% of elemental Ca, relevant amounts of Sr, and low levels of Al, Pb, Cd and Hg. It may be used as a Ca source in human nutrition.

Aged↗
PubMed2000

Fish oil supplementation improves docosahexaenoic acid status of malnourished infants.

AIM: To investigate whether the low docosahexaenoic acid (DHA) status of malnourished, mostly breast fed, Pakistani children can be improved by fish oil (FO) supplementation. METHODS: Ten malnourished children (aged 8-30 months) received 500 mg FO daily for nine weeks. The supplement contained 62.8 mol% (314 mg) long chain polyunsaturated fatty acids of the omega3 series (LCPUFAomega3) and 22.5 mol% (112 mg) DHA. Seven FO unsupplemented children served as controls. Red blood cell (RBC) fatty acids were analysed at baseline and at the study end. RESULTS: FO supplementation augmented mean (SD) RBC DHA from 2.27 (0.81) to 3.35 (0.76) mol%, without significantly affecting the concentrations of LCPUFAomega6. Unsupplemented children showed no RBC fatty acid changes. One FO supplemented child with very low initial RBC arachidonic acid showed a remarkable increase from 4.04 to 13.84 mol%, whereas another with high RBC arachidonic acid showed a decrease from 15.64 to 10.46 mol%. CONCLUSION: FO supplementation improves the DHA status of malnourished children. The supplement is apparently well absorbed and not exclusively used as a source of energy.

Breast Feeding↗
PubMed2000

Breast milk docosahexaenoic acid (DHA) correlates with DHA status of malnourished infants.

AIM: To investigate whether low docosahexaenoic acid (22:6omega3; DHA) status of malnourished, mostly breast fed infants is a result of low omega3 fatty acid intake via breast milk. METHODS: Fatty acid composition of breast milk of eight Pakistani mothers, and of the erythrocytes of their malnourished children was analysed. RESULTS: The milk of the Pakistani mothers contained low percentages of all omega3 and most omega6 fatty acids, compared with milk of Dutch mothers. Breast milk DHA was positively correlated with infant erythrocyte DHA and arachidonic acid (20:4omega6). CONCLUSION: DHA status of these malnourished children is strongly dependent on the omega3 fatty acid intake from breast milk. Augmentation of the infants' omega3 long chain polyunsaturated fatty acid status, or the omega3 and omega6 fatty acid status in general, by supplementation is indicated in deprived circumstances where access to fresh fish is difficult. However, in terms of prevention, maternal supplementation of these long chain polyunsaturated fatty acids, preferably from early pregnancy onwards, may be a better option.

Biomarkers↗
PubMed2000

Phase I and pharmacological study of weekly administration of the polyamine synthesis inhibitor SAM 486A (CGP 48 664) in patients with solid tumors. European Organization for Research and Treatment of Cancer Early Clinical Studies Group.

A single-agent dose-escalating Phase I and pharmacological study of the polyamine synthesis inhibitor SAM 486A was performed. A dosing regimen of four weekly infusions followed by 2 weeks off therapy was studied. Fifty patients were entered into the study. Dose levels studied were 1.25, 2.5, 5, 8, 16, 32, 48, 70, 110, 170, 270, and 325 mg/m2/week. Pharmacokinetic sampling was done on day 1, and trough samples were taken weekly during the first treatment cycle. Pharmacodynamic sampling was done on days 1 and 22. At 325 mg/m2/week, dose-limiting toxicity was seen (one patient each with grade 4 febrile neutropenia, grade 3 neurotoxicity, and grade 3 hypotension with syncope and T-wave inversions on electrocardiogram). The recommended dose for further testing was set at 270 mg/m2/week. Infusion time was increased from 10 to 180 min due to facial paresthesias and flushing and somnolence. Drug exposure increased linearly with dose. Mean +/- SD t1,2 at 70-325 mg/m2 doses was 61.4+/-26.2 h, with a large volume of distribution at steady state. In peripheral blood leukocytes, a clear relationship between dose and inhibitory effect on S-adenosylmethionine decarboxylase or changes in intracellular polyamine pools was not recorded. SAM 486A can be administered safely using a dosing regimen of four weekly infusions followed by 2 weeks off therapy. The recommended dose for Phase II studies using this regimen is 270 mg/m2/week.

Adult↗