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M D Laryea

Publications and source records attributed to M D Laryea.

At least 19 recordsLinked to original sources
PubMed1998

Simple method for the routine determination of betaine and N,N-dimethylglycine in blood and urine.

A simple and convenient method using commercially available derivatization reagents is described for the measurement of betaine and N,N-dimethylglycine (DMG) in blood and urine. Precolumn derivatization of plasma or urine is performed directly in acetonitrile without extraction with p-bromophenacyl bromide and crown ether as catalyst. The p-bromophenacyl ester derivatives are then separated by high-performance liquid chromatography, using an isocratic system of acetonitrile and water containing choline. Effluent was monitored at 254 nm. The limit of detection was 5 micromol/L for betaine and 2 micromol/L for DMG. Analytical recovery was >97% for both analytes. Total and within-day CVs were 2.0-4.4% and 0.9-2.2% for DMG. For betaine, the total and within-day CVs were 1.3-5.3% and 0.4-3.8%, respectively. The method is precise and cost-effective and has been used successfully to determine the concentrations of DMG and betaine in human plasma and urine.

Adult↗
PubMed1995

Macronutrient, copper, and zinc intakes of young German children as determined by duplicate food samples and diet records.

Daily energy, protein, fat, carbohydrate, zinc, and copper intakes of 47 healthy 5- to 9-year-old children living in Duisburg, an industrial area of North Rhine-Westphalia, and consuming self-selected diets were calculated using a 4-day weighed dietary records and food composition values. In addition, the parents of the subjects also collected a 24-hour food composite on 2 of the recording days for analysis of the nutrients. This allowed us to compare the calculated value of the nutrients on days when only dietary records were made with those on which also duplicate samples were collected. Daily analyzed intakes were also compared with those calculated from the recording days. Zinc and copper were estimated by atomic absorption spectrometry. The results show that there were reductions in the intake of all nutrients on days when duplicate samples were also collected as compared with the days when only dietary records were made. Median daily calculated intakes for all children on the 4 record days were: energy 1,578 kcal, protein 46.5 g, fat 67.3, carbohydrates 174.7 g, zinc 5.3 mg, and copper 1.0 mg. The median analyzed intakes were: energy 1,367.7 kcal, protein 37.1 g, fat 49.1, carbohydrates 178.7 g, zinc 5.3 mg, and copper 0.7 mg. The use of the duplicate diet method has shown that a 4-day recording period gives an overestimation of the nutrient intake. The calculated and the analyzed zinc intakes did not meet the recommended levels of the Deutsche Gesellschaft für Ernährung. The median copper intakes were in the lower range of the levels recommended by the Deutsche Gesellschaft für Ernährung.

Child↗
PubMed1995

Fatty acid composition of the milk of well-nourished Sudanese women.

The fatty acid (FA) composition of samples of breast milk obtained from well-nourished Sudanese women was determined by capillary gas chromatography. Saturated fatty acids (SFA) constituted 46%, monoenoic acids (MONOENE) 33% and polyunsaturated fatty acids (PUFA) accounted for 21% of total fatty acids. The mean value (18.28%) of the essential fatty acid linoleic acid was comparable to the levels reported for well-nourished mothers from industrialised countries. The proportions of fatty acids synthesised de novo in the mammary gland (10:0, 12:0, 14:0) were less than expected from published studies of mothers consuming low fat diet averaging 17.4%. The amount of 22:6 n-3 which is synthesised from 18:3 n-3 and also taken up by consumption of fish were found to be low. The possible nutritional implications of the low n-3 fatty acids for the infants should therefore be investigated.

Adolescent↗
PubMed1994

Simultaneous determination of betaine and N,N-dimethylglycine in urine.

A method is described for the determination of betaine and its metabolite N,N-dimethylglycine in human urine. The method involves a deamination step and a solid-phase extraction to isolate both substances from urine followed by high performance liquid chromatography (HPLC) separation on a 5-microns SCX column with UV absorbance detection. Limit of detection is about 0.9 micrograms for both substances. Recoveries were > 85%. The method appears to be suitable for monitoring betaine and its metabolite in urine of patients undergoing therapy with betaine.

Betaine↗
PubMed1993

Scaly skin alterations and plasma fatty acids in Congolese children.

Scaly skin alterations on the surface of the legs are frequently found in African children. Because similar signs occur in essential fatty acid deficiency, the fatty acid status of a group of African children with (n = 10) and without (n = 27) such skin alterations was determined. Analysis of the fatty acid composition of the plasma phospholipid and cholesterol ester fractions as well as clinical examinations were performed. Constantly low levels of linoleic acid and arachidonic acid were not associated with the occurrence of scaly skin alterations, which were also found in children with normal values for these polyunsaturated fatty acids. It is suggested that scaly skin alterations in Congolese children are not a sign of essential fatty acid deficiency.

Adolescent↗
PubMed1992

The fatty acid composition of subcutaneous fat in German adults.

The fatty acid (FA) composition of subcutaneous fat (SCF) was analyzed in 47 German adults. No influences of sex or age on the FA status of the probands could be detected. SCF consisted mainly of monoenoic fatty acids. Linoleic acid was the major polyunsaturated fatty acid. Linoleic acid metabolites were found in small quantities only. In comparison to the results of studies in the USA and the Netherlands the FA composition of SCF in German probands was characterized by lower levels of linoleic acid and higher contents of palmitic acid. The trans-FA content was similar to that in Dutch women, but lower than in American male probands. However, in evaluating the differences in the FA composition of SCF in different countries, it has to be noted that there are wide ranges in the proportions of the major FA in all populations studied.

Adipose Tissue↗
PubMed1992

Fatty acid composition of blood lipids in Chinese children consuming high erucic acid rapeseed oil.

The fatty acid patterns of oils, blood plasma and erythrocyte lipids from 28 children in the Shaanxi province of the People's Republic of China were determined by capillary gas liquid chromatography. The main source of fat in this region is rapeseed oil. The analysis of locally available rapeseed oil shows a high erucic acid content (mean 43.83%, range 33.91-50.48%). According to protocol data, about 3% of the daily nutrient energy is provided by erucic acid. Despite a low fat intake in Chinese children, the composition of the fatty acids of the fractions analyzed showed normal patterns. However, erucic acid was found in all fractions analyzed. Data on erucic acid in human tissue are scarce. Although there are no indications of erucic acid toxicity in man, it is known to cause cardiac lipidosis and necrosis in rats. The question remains open if erucic acid aggravates selenium deficiency symptoms which are known to be associated with Keshan disease, an endemic cardiomyopathy.

Adolescent↗
PubMed1992

Relationship among the fatty acid composition of various lipid fractions in normally nourished German adults.

The relationship among the fatty acid (FA) composition of plasma cholesteryl esters (CE), plasma phospholipids (PL), total erythrocyte lipids, erythrocyte phosphatidylethanolamine (PE), erythrocyte phosphatidylcholine (PC), and total lipids of the subcutaneous fat (SCF) was investigated by parallel analyses of samples from 47 normally nourished German adults. Each lipid fraction revealed a characteristic FA pattern. A close relation between major FA in plasma lipids, especially in CE, and those in PC was found. The FA composition of PE, however, appeared to be more independent from plasma values. Of all FA in SCF only linoleic acid values showed a correlation to the values in CE and PC. It is concluded that, in clinical studies, FA analyses of total plasma lipids or total erythrocyte lipids fractions should be avoided in favour of separate analyses of various lipid fractions.

Adolescent↗
PubMed1990

Fatty acid composition of phospholipids of plasma and of mononuclear blood cells in children with allergic asthma and the influence of glucocorticoids.

Fatty acid (FA) composition of plasma phospholipids and phospholipids extracted from peripheral mononuclear white blood cells (MNC) was investigated in 11 allergic asthmatic children (age 8.9 +/- 4.6 years), in 10 age-matched non-allergic healthy controls and in 14 allergic and non-allergic children with an acute attack of asthma, who had received prednisolone medication for 2-4 days. In allergic asthmatics eicosapentaenoic acid (20:5n-3) was significantly elevated in both plasma and MNC. The relative amount of 20:5n-3 in MNC as well as in plasma correlated positively with increasing levels of total serum IgE (P less than 0.02). The pattern of the other FAs in plasma and of MNC phospholipids did not differ between allergic asthmatic and non-allergic control children. In children with an acute attack of asthma, who had been treated with glucocorticoids (2 mg prednisolone/kg body weight for 2-4 days), distinct changes of relative FA composition of phospholipids were restricted to plasma, where some very long chain FA (22:4n-6, 22:5n-6) were elevated. No significant changes in FA from MNC phospholipids could be observed after glucocorticoid treatment. These findings may indicate a possible role of 20:5n-3, the precursor of "group 3" eicosanoids, in allergic asthmatic children.

Adolescent↗
PubMed1990

Vitamin E status in Sudanese children with protein-energy malnutrition.

Total tocopherols and alpha-tocopherols were estimated in the plasma of children with severe malnutrition (14 marasmus; 11 marasmic kwashiorkor; five kwashiorkor) and related to the total plasma lipids and different plasma lipid classes. If the mere plasma concentrations were taken as an index of the vitamin E status, five children with marasmus, five children with marasmic kwashiorkor, and two children with kwashiorkor would have been regarded as deficient (less than 500 micrograms/dl). However, if total tocopherols and alpha-tocopherols were related to the total plasma lipids, all malnourished children--except one--showed values within the limits found in healthy American children. The study shows that low tocopherol/lipid ratios are not a constant feature in severely malnourished children.

Child, Preschool↗
PubMed1990

Vitamin E status of Congolese children in a rural area.

The role of vitamin E in severe malnutrition is controversially discussed. In order to evaluate the vitamin E status of unselected African children the plasma tocopherol levels of 52 children from a village in the People's Republic of Congo were assessed by HPLC and related to the plasma lipid values. Although plasma concentrations of total tocopherols (mean 351.1 +/- 59.4 micrograms/dl) and alpha-tocopherol (mean 313.3 +/- 57.0 micrograms/dl) were found to be low, normal ratios of total tocopherols to total lipids (mean 0.99 +/- 0.17 mg/g) and alpha-tocopherol to total lipids (mean 0.89 +/- 0.09 mg/g) were estimated. It is concluded that plasma vitamin E levels should be related to plasma lipids if populations are monitored in which low lipid concentrations have to be expected. These data on Congolese children may be used for comparison if the vitamin E status in other agrogeographical areas of Africa or in clinically abnormal groups is investigated.

Adolescent↗
PubMed1989

A screening method for the evaluation of selenium status.

A screening test for the estimation of the Se content in whole blood was developed. Blood was administered on to filter paper, dried at room temperature and circles of 28 mm circumference cut out. The blood volume corresponding to the stained circle amounted to 17.0 +/- 1.4 microL. The Se content was estimated by atomic absorption spectrophotometry + hydride generation technique after stepwise digestion of the blood stained filter papers. Precision (within-run 6.3%) and recovery rate (102%) were good. The screening test was used for samples from Magnesia, an area on the east coast of Greece, and Ningxia, a rural area in northeast China. The blood Se content was significantly lower in Greek mothers after birth than in Chinese mothers. Greek newborns had higher blood Se than their mothers. Greek infants showed a drastic decline in the blood Se values within the airst 4 months of life. The screening method showed good practicability in testing the blood Se content in samples from different areas of the world.

Capillaries↗
PubMed1989

Plasma tocopherol and tocopherol to lipid ratios in a normal population of infants and children.

The plasma tocopherol concentrations were measured by HPLC in 73 apparently healthy West German children aged from 1 to 14 years and in 7 cord blood samples and 5 infants below 1 year of age. Total tocopherols ranged from 584 to 2024 micrograms/dl in the children above 1 year of age (mean 1046 +/- 283 micrograms/dl) and from 511 to 1155 micrograms/dl in the infants below 1 year of age (mean 879 +/- 270 micrograms/dl). The total tocopherol/total lipid ratio-representing the reliable index for vitamin E status-was far above 0.6 mg/g lipid, a level which is regarded as the lower limit of normal (range 1.23 to 4.09 mg/g total lipid in the older children and 1.52 to 2.05 in the infants below 1 year). A positive correlation was found between plasma lipids and total tocopherol (r = 0.71). Our investigation demonstrated an excellent vitamin E status in the children investigated which is considered to reflect the high supply of West German food with PUFA and vitamin E.

Adolescent↗
PubMed1989

Plasma retinol and tocopherols of breast-feeding Sudanese women.

The status of vitamin A and vitamin E has been evaluated in 69 well-nourished breast-feeding Sudanese women of two villages of the irrigated Gezira area. All were consuming local Sudanese food. Plasma retinol, alpha-tocopherol, and total tocopherol were estimated by HPLC. Tocopherol values have been related to total plasma lipids, cholesterol and phospholipids. The plasma retinol concentrations ranged between 29.19-141.37 micrograms/dl (mean 63.01 micrograms/dl). All values are well above 20 micrograms/dl, the lower cut-off point of normal, and reveal a good vitamin A status. The ratio of total tocopherol/total lipids (mg/g) was with 1.35-2.72 far above the lowest normal ratio of 0.60. This means an excellent vitamin E status. Neither the retinol nor the tocopherol values showed a correlation to parity or duration of breast-feeding.

Adolescent↗
PubMed1988

Analysis of the fatty acid composition of erythrocyte phospholipids by a base catalysed transesterification method--prevention of formation of dimethylacetals.

A sensitive method for the analysis of the fatty acid composition of erythrocyte phospholipids with capillary column GLC is described. Under the assay conditions (base catalysed transesterification with sodium methoxide), only the fatty acids of the phospholipids are converted to their methylesters. The alkenyl ether chains of the plasmalogens are not transmethylated. This eliminates the need for thin layer chromatography for the separation of dimethylacetals and esterified fatty acids. The method is suitable for the measurement of the fatty acid patterns of erythrocyte phospholipids in small blood samples.

Acetals↗
PubMed1988

Investigation of the nutritional state of children in a Congolese village. II. Plasma fatty acid composition.

The fatty acid status of an unselected group of 84 Congolese children was determined by estimating the fatty acid composition of the plasma phospholipid (PL) and cholesterolester (CE) fractions using capillary gas chromatography. In comparison with North American and European children a wide range of values and low mean percentages (related to the fatty acids of a chain length of 14-24 carbon atoms) were found for the following fatty acids (mean +/- SD): linoleic acid (LA) (PL: 17.19 +/- 3.85; CE: 40.13 +/- 7.72); arachidonic acid (AA) (PL: 6.60 +/- 2.28; CE 4.32 +/- 1.71); dihomo-gamma-linolenic acid (DHLA) (PL: 1.80 +/- 0.68; CE 0.41 +/- 0.22). On average, omega 3 fatty acids were higher than in reference groups, while similar values were found for the monoenoic and omega 9 fatty acids. No sample contained eicosatrienoic acid, 20:3 omega 9 (ETA) which, dependent on analytical methods, may be difficult to separate from behenic acid (22:0). Changes in the relation between the two lipid fractions occurred when the LA content in CE was less than 35%. Also the correlation between LA and AA in CE, which was significant below 35% LA (r = 0.84), changed with higher values for LA (r = 0.01). These findings may indicate that alterations in fatty acid metabolism occur when LA values in CE--which are supposed to be directly related to the dietary intake of polyunsaturated fatty acids--fall below 35% of all fatty acids in this lipid fraction.

Adolescent↗