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G Wolfram

Publications and source records attributed to G Wolfram.

At least 55 records · Page 3Linked to original sources
PubMed1997

[Differences in nutrient intake using different nutrient databases-- an example].

Mean dietary intake calculated from 25 7-day-food records by means of the three nutrient data bases modified Souci/Fachmann/Kraut (mSFK) 1986/87, extract of Bundeslebensmittelschlüssel (BLS) version 2.1, and extract of BLS version 2.2 revealed comparable results only for four of 27 nutrients considered. The greatest deviations were found for zink, fluoride, iodine, vitamin D, vitamin C, and dietary fiber. Comparing the revised BLS version 2.2 and mSFK, the differences in fluoride, iodine and dietary fiber intake data were markedly lower than found with the comparison of BLS 2.1 and mSFK; statistically significant differences no longer existed for the vitamins C and A (equivalents). As expected, using the mSFK data base with some missing fields for analytical data underestimation of nutrient intake could be shown for the trace elements zink, fluoride and iodine. With regard to the given results of the investigated group, care has to be taken with some nutrient intake data gathered by means of BLS 2.1, too.

Diet Records↗
PubMed1997

[Flavonoid intake of adults in a Bavarian subgroup of the national food consumption survey].

Flavonoids as naturally occurring compounds of plant derived foodstuff reveal some biological effects (antioxidative, antimutagenic, anticarcinogenic) which makes them interesting substances in the prevention of atherosclerosis and cancer in humans. Data on the flavonoid content of food are not considered in food composition tables, and human intake data are scarce (flavonols) or missing. Consequently, after installing a flavonoid data base by means of literature data, 7-d dietary protocols of 119 adults (63 women and 56 men, age 19-49 years) representing a bavarian subgroup of the German National Food Consumption Survey (NVS) were evaluated. In all subjects, average intake of all flavonoids (calculated as aglycons) amounts to 54.0 mg/d (median) with a great range of variability. The most important flavonoid groups are flavonols (12.0 mg/d), catechins (8.3 mg/d), and flavanons (13.2 mg/d), followed by anthocyanidins (2.7 mg/d), proanthocyanins (3.7 mg/d) and phloretin (dihydrochalcone) (0.7 mg/d). Sex differences did not reach statistical significance. Fruits, fruit products and fruit juices were the most important flavonoid sources. Vegetables and its products provided about half of the flavonol intake. Therefore, statistically significant correlations (p < 0.001) exist between total flavonoid intake and the intake of vitamin C (r = 0.59) or dietary fiber (r = 0.49). Compared to other countries, flavonol intake of the investigated group of persons is rather low. With the built data base it was possible for the first time to calculate the intake of further flavonoids besides flavonols. In comparison to the intake of other antioxidants (e.g. vitamins C and E) the amount of flavonoids in the diet is considerably high and therefore should be regarded in further investigations on the role of diet in certain diseases.

Adult↗
PubMed1997

Transcripts encoding three types of guanylyl-cyclase-coupled trans-membrane receptors in inner ear tissues of guinea pigs.

The distribution of membrane-bound guanylyl cyclase (GC) transcription in inner ear tissues of the guinea pig was addressed by a reverse transcription-PCR approach using consensus primers flanking a region of about 630 bp in the intracellular domains in the target sequences. Restriction mapping of such amplificates obtained from cochlear and vestibular specimens permitted us to demonstrate GC-A, GC-B, and GC-C expression by differentiating overall PCR signals. This assay indicated that GC-A was expressed in the cochlea and vestibular organ. PCR products resulting from transcripts of the GC-B gene were obtained at considerably lower abundance than amplificates typical of the GC-A gene. The consensus primer approach with subsequent restriction mapping provided the opportunity to examine at the same time expression of GC-C in the inner ear and revealed the occurrence of GC-C transcripts in both inner ear compartments under investigation. The distribution pattern found by analysing the intracellular domains of membrane-bound guanylyl cyclases was confirmed by demonstrating transcription of the corresponding extracellular receptor domains. In addition, single-strand conformation polymorphism analysis of cDNA amplificates comprising the catalytic domain of guanylyl cyclases also indicated the presence of GC-C expression in the inner ear tissues examined. The GC-C transcripts detected in inner ear tissues appeared to correlate with functional receptor expression, since the production of cyclic GMP catalyzed by cochlear and vestibular specimens was stimulated by 1 microM of heat-stable enterotoxin to 18 and 80% above basal levels, respectively. Thus, GC-C may be involved in the fluid regulation by typical ligands (e.g., the peptide hormone guanylin or the toxins causing travellers' diarrhea), not only in the intestine but also in the organs responsible for hearing and gravitational orientation.

Animals↗
PubMed1997

Determination of total homocysteine in human plasma by isocratic high-performance liquid chromatography.

A simple, sensitive and precise isocratic HPLC method for the determination of total homocysteine in human plasma is described. The thiol compounds were liberated from plasma proteins by reduction with tri-n-butylphosphine and derivatized with a thiol-specific fluorogenic marker, 7-fluoro-benzo-2-oxa-1,3-diazole-4-sulphonate. The derivatives were separated isocratically within 7 min by reversed-phase HPLC using a Superspher 100 RP-18 column as stationary phase. By using this approach more than 200 samples a day can be assayed for total homocysteine. The method was linear up to 100 mumol/l and proved to be sensitive with a detection limit of 0.1 mumol/l and the lowest limit of reliable quantification of 0.5 mumol/l for homocysteine in buffer. Intra- and inter-assay coefficients of variation were both < 4% at a concentration of 10 mumol/l homocysteine. Similar results were obtained for homocysteine concentrations between 0.5 and 100 mumol/l. The analytical recovery for these concentrations ranged from 94.9 to 117.0%. As compared to other protocols published so far, this modified method is less complicated but equally sensitive and reproducible and allows a rapid determination of total homocysteine and cysteine in human plasma under routine conditions.

Chromatography, High Pressure Liquid↗
PubMed1996

Effect of organic nitrates on ex vivo platelet aggregation and fibrinolysis in man.

Previous in vitro studies have suggested that nitric oxide-releasing agents can increase the fibrinolytic capacity while platelet aggregability is decreased. We have therefore directly compared the influence of organic nitrates on ex vivo platelet aggregation and the fibrinolytic system in 16 healthy volunteers. Each subject received glyceryl trinitrate (GTN, 2 x 32 mg patches), isosorbide-dinitrate (ISDN, 120 mg p.o.), isosorbide-5-mononitrate (ISMN, 50 mg p.o.), and placebo in a randomized double-blind manner. Ex vivo platelet aggregation, activities and concentrations of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) were measured before, 90 and 150 minutes after drug intake. GTN, ISDN, and ISMN were equipotent in respect to their hemodynamic responses. Platelet aggregation induced with a low (1 microM) but not with a high (4 microM) agonist concentration (adenosine diphosphate, ADP) was reduced after GTN and ISDN. ISMN had no influence on aggregation. An increase of t-PA activity was significantly reduced after GTN and ISDN (p<0.05), whereas t-PA concentrations were not affected by the nitrates. A decrease of PAI-1 activity after ISMN and placebo was not apparent after GTN and ISDN. In the case of GTN, the decrease of PAI-1 concentration was delayed. In conclusion, GTN and ISDN did not increase the fibrinolytic capacity but decreased the reversible phase of ADP-induced platelet aggregation, while ISMN had neither an effect on the fibrinolytic system nor on platelet aggregation.

Adenosine Diphosphate↗
PubMed1996

Influence of knowledge on iodine content in foodstuffs and prophylactic usage of iodized salt on urinary iodine excretion and thyroid volume of adults in southern Germany.

Thyroid volume, urinary iodine excretion as well as personal nutritional knowledge and individual iodine prophylaxis were determined during a health education program on iodine deficiency and prophylaxis in 1992. Participants were 472 male and 568 female (mean age 27.7 years) students and employees of five universities in the southern part of Germany. The study aimed to clarify the relationship between personal knowledge on iodine, individual iodine prophylaxis and parameters of iodine deficiency (thyroid volume, iodine excretion) in a well known iodine deficient area. Mean thyroid volume (mean +/- SD) was 19.7 +/- 8.3 ml in males and 15.8 +/- 7.1 ml in females. 25.5% of females and 19.9% of males showed thyroid volume above the upper normal values. Total mean urinary iodine excretion was 70.7 +/- 42 micrograms I/g creatinine reflecting WHO-grade-I iodine deficiency. 80.8% of total subjects used iodized salt and 43.2% stated to consume salt-water fish to meet their iodine requirement. The female non-users had significantly lower iodine excretion (no iodized salt, no salt-water fish: 61.4 +/- 31.3 vs. +iodized salt, +salt-water fish: 83.9 +/- 47.6 micrograms I/g creatinine; p < 0.05), however, thyroid volume was identical in these groups. The area of residence over the last 10 years did not significantly influence the thyroid volume. The goiter incidence increased with age. Although our study population was highly educated (81.8% students) and the subjects were provided with educational brochures immediately prior to the study, knowledge about iodine content of food was poor. We conclude that despite a high degree of voluntary iodine prophylaxis and educational programs the iodine intake is insufficient. The use of iodized salt in households, cafeterias, and also in food manufacturing must be increased for sufficient iodine prophylaxis.

Adult↗
PubMed1996

Trans fatty acid contents in spreads and cold cuts usually consumed by children.

A high intake of trans fatty acids in children may be disadvantageous because of untoward effects on lipoprotein metabolism and a possible impairment of arachidonic acid synthesis. We measured the trans fatty acid content of different brands of spreads and cold cuts typically consumed by German children because these foods may contribute a considerable portion of total trans fatty acid intake. The highest trans fatty acid contents were found in regular margarines (4.5, 0.0-10.6; median %-wt/wt of fatty acids, minimal-maximal), chocolate spreads (5.5, 0.7-11.1), butter (4.7, 3.7-5.2) and cheese (3.6, 1.8-4.0), while lower values were present in diet margarines (0.2, 0.0-0.4), vegetarian spreads (0.2, 0.1-0.4), peanut butter (0.0, 0.0-0.3) and sausages (1.7, 0.6-6.4). Calculations of typical dietary plans for young children show that food selection and variations in trans fatty acid contents may lead to marked differences in daily trans intake of > 100% (3.1 g/d vs. 1.5 g/d). We propose that trans fatty acid content should be declared on labels of fatty food products to enable the consumer to choose, and further attempts should be made to lower trans fatty acid formation during technical hydrogenation.

Animals↗
PubMed1996

Weight gain and increased concentrations of receptor proteins for tumor necrosis factor after patients with symptomatic HIV infection received fortified nutrition support.

OBJECTIVE: To determine whether certain nutrients and dietary factors act as modulators of the immune system and improve the nutritional status of immunocompromised patients. DESIGN: Controlled, double-blind, crossover phase trials of the effects of a fortified formula in patients infected with the human immunodeficiency virus (HIV). Patients consumed a control formula for 4 months and a study formula for 4 months. SUBJECTS: Ten men with symptomatic HIV infection who were following stable medication regimens and had no malignancies, mycobacteriosis, or additional virus infection requiring systemic treatment. INTERVENTION: Formula fortified with alpha-linolenic acid (1.8 g/day), arginine (7.8 g/day), and RNA (0.75 g/day) and a standard formula. MAIN OUTCOME MEASURES: Nutritional status determined by anthropometric, bioelectrical, biochemical, and dietary assessment; energy expenditure determined by indirect calorimetry; disease progression; CD4 lymphocyte counts; HIV p24 antigen plasma concentrations; tumor necrosis factor (TNF) receptor proteins; and compliance control parameters. STATISTICAL ANALYSES PERFORMED: Student's t tests for paired and unpaired data. RESULTS: Fortified nutrition resulted in a weight gain (+ 2.9 kg/4 months vs -0.5 kg/4 months with the control formula, P < .05), an incorporation of eicosaenoic acid into erythrocyte cell membranes (+ 47% of baseline values, P < .05), and increased plasma arginine concentrations (96.8 +/- 45.1 vs 51.8 +/- 20.9 mumol/L, P < .01). The serum concentrations of the soluble tumor necrosis factor receptor (sTNFR) proteins increased during the study period (sTNFR 55 = + 0.23 vs -0.40 ng/mL, P < .001; sTNFR 75 = + 0.90 vs -0.36 ng/mL, P < .01), whereas no changes in CD4+ lymphocyte counts were observed. CONCLUSION: Increasing dietary intakes of n-3 polyunsaturated fatty acids, L-arginine, and RNA increased body weight, possibly by modulating the negative effects of TNF.

Adolescent↗
PubMed1996

Effect of fluvastatin or bezafibrate on the distribution of high density lipoprotein subpopulations in patients with familial hypercholesterolemia.

In eight patients with familial hypercholesterolemia the effects of two lipid reducing drugs on subpopulations of high density lipoproteins (HDL) were examined. After a 14-week period of diet and diet/placebo a 12-week therapy followed with either bezafibrate (CAS 41859-67-0) or fluvastatin (CAS 93957-55-2). Throughout both treatments a significant decrease of total and low density lipoprotein (LDL)-cholesterol, apolipoprotein B and triglycerides during both therapies were noted as well as an insignificant increase of HDL-cholesterol during bezafibrate. The nondenaturating gradient gel electrophoresis is a valid method for the investigation of the behaviour of HDL and was therefore chosen for this investigation. The individual HDL pattern and HDL diameters did not change in these subjects. The effect on the amounts of HDL 3b and HDL 3c was significantly more extensive during fluvastatin (+2.4% resp. + 2.9%) as compared to during bezafibrate therapy (+1.7% resp. + 2.9%). The changes noted in the HDL subclasses are probably due to a variable lipoprotein metabolism, for example increased activity of lipoprotein lipase, hepatic triglyceride lipase, lecithin-cholesterol acyltransferase and cholesterol ester transfer protein.

Adult↗
PubMed1995

Iodine concentration in canteen meals prepared with or without iodized salt.

In each of two university canteens differing in the use (canteen A) or non-use (canteen B) of iodized salt for food preparation, 15 mostly equal lunch meals were collected for iodide and NaCl analysis. With similar NaCl content, the meals of canteen A contained on average 6.1 micrograms I/100 g ww (8.5 micrograms I/g NaCl) more I than the meals of canteen B. Total I intake by consumption of an average meal of canteen A was estimated as 56.5 +/- 24.1 micrograms (canteen B: 17.0 +/- 9.9 micrograms). Consequently, the use of iodized salt in central catering seems to play a more important role in a sufficient I intake than assumed so far.

Cooking↗
PubMed1995

Identification of the valine 408 to methionine mutation in the LDL receptor in a Greek patient with homozygous familial hypercholesterolemia.

We have identified the cytosine to thymine change in the codon for amino acid 408 which causes valine to be replaced by methionine in exon 9 of the LDL receptor gene in a 12-year-old Greek boy living in Germany, with homozygous familial hypercholesterolemia, by using polymerase chain reaction-amplified genomic DNA and subsequent restriction digestion. Homozygosity was confirmed by direct DNA sequencing. The mutation was present in both his parents, and his brother, grandmother, uncle and cousin. Six restriction fragment length polymorphisms of the LDL receptor gene were used to determine the haplotype of the defective allele. The haplotype was different from the one reported earlier in African Afrikaners and from Holland. We conclude that the mutation in the Greek boy probably occurred as an independent mutation. Because the parents are from different areas in Greece, this mutation may be common in Greeks.

Base Sequence↗
PubMed1995

Ten LDL receptor mutants explain one third of familial hypercholesterolemia in a German sample.

Mutational defects in the LDL receptor are responsible for familial hypercholesterolemia (FH); thus far more than 150 mutations have been described. Nevertheless, systematic searches among the Germans have not been conducted. We used single-strand conformational polymorphism and polymerase chain reaction to find mutations in 10 index patients and in 40 other individuals with heterozygous FH. Our screen in the 10 index patients revealed 7 hitherto undescribed mutations. A screen of the 40 additional FH patients disclosed 20 defective of 54 total alleles and allowed specific diagnoses in 88 family members. We also found two families in which the children were markedly affected by FH, but the expected parental expression of the trait was not manifest. This observation suggests a role for additional environmental and genetic influences. Our report represents the first comprehensive effort to identify FH mutations in Germany. We found 10 mutations and these mutations explain 37% of FH cases. Our data may have relevance to expected FH patterns in central Europe.

Adult↗
PubMed1995

[Diet therapy in gout].

In gout, an effective diet is important to avoid or to lower complications and expenses of drug treatment. Most important dietary measures are reduction of purine uptake and alcohol consumption and normalization of body weight. Purine content of food can be altered quantitatively and qualitatively by storage and cooking with consequences for digestion and absorption of purines. The modern concept of diet in gout takes into consideration the purine content of food per weight, per portion and per energy.

Alcohol Drinking↗