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Biomedical subjects

K Pietrzik

Publications and source records attributed to K Pietrzik.

62 records · Page 4Linked to original sources
PubMed1975

[Urinary excretion of pantothenic acid as a measurement of nutritional requirements].

Several groups of male Wistar-Rats were fed for 15 month with a purified diet containing different amounts of pantothenic acid. The groups received 150, 100, 25 and 0% pantothenic acid of the requirement respectively. A further group was fed without pantothenic acid in the diet but administered with the antagonist omega-methyl-pantothenic acid. The excretion of pantothenic acid in the urine was measured at different times, and a groups specific level of excretion could be established for the different groups. Differences to the controls were highly significant in the test groups after 2-18 weeks. Studies of this type were conducted in order to obtain basic informations for later experiments in human beings.

Animals↗
PubMed1975

[Influencing of acetylation and corticosterone biosynthesis through long-term pantothenic acid deficiency in rats].

The effect of different dietary intake of pantothenic acid (150;100;25 and 0% of the requirement) on the metabolism of rats was studied during 15 months. The ability of the adrenals for synthesis of corticosterone and the rate of acetylation of a sulfonamid (Sulfisomidin) were taken as parameters. The above mentioned parameters were influenced significantly already after two weeks and a pantothenic acid free diet containing the antagonist omega-methyl-pantothenic acid. With a 25% supply of pantothenic acid and without omega-methyl-pantothenic acid it lasted half a year until significant alterations of acetylation could be demonstrated. The synthetic ability of the adrenals for corticosteroids was significantly increased after a year in the 25% group. After the end of the study, this hyperfunctional state was followed by hypofunction, resulting in a significantly reduced ability of synthesis of the glands. Studies of this type were conducted to obrain basic informations for later experiments in human beings.

Acetylation↗
PubMedDate not supplied

B-vitamin status and intake in European adolescents. A review of the literature.

BACKGROUND: National and international recommendations for the intake of B vitamins in adolescents consist of estimates and extrapolations from adult values. Due to increasing growth and therefore relatively high energy and nutrient requirements adolescents are a vulnerable group from the nutritional point of view. In addition, a deficient intake of several B vitamins is strongly connected with the development of cancer, neural tube defects and cardiovascular diseases. OBJECTIVE: The aim of this work is to assess dietary intake and status of B vitamins and homocysteine of European adolescents on the basis of published data. METHODS: The database Medline (www.ncvi.nlm.nih.gov) was searched for terms like "Vitamin B", "homocysteine", "Europe", etc. Studies published between June 1980 and December 2004 were analysed for this review. Results of the intake of B vitamins were compared with the EAR or AI, respectively, as recommended by the U.S. Institute of Medicine. Due to lacking reference values for adolescents results of blood status as well as homocysteine were compared to different thresholds for adults. RESULTS: Considering the limitations of the comparability between the reviewed studies e.g. by different methodologies, sample size, age groups, the average intake of B vitamins surpassed the EAR and AI. Boys were better supplied with B vitamins than girls. The intake decreased with increasing age in both genders. A possible deficiency of folate was noticed and girls in particular seemed to be more at risk. Clear regional tendencies for the vitamin intake could not be observed. Results of vitamin B6, B12, folate in blood, and homocysteine were levelled in-between the thresholds. Though the great standard deviation of folate increased the probability of a deficient supply in parts of the population. CONCLUSIONS: European girls seem to be at risk of folate deficiency. Supplements and fortified food were not taken into consideration by most of the published studies which additionally distorts the real intake. Standardized methods of dietary surveys and reference values for B vitamins as well as homocysteine still must be established. Hence, further investigations are of great relevance. folate increased the probability of a deficient supply in parts of the population. CONCLUSIONS: European girls seem to be at risk of folate deficiency. Supplements and fortified food were not taken into consideration by most of the published studies which additionally distorts the real intake. Standardized methods of dietary surveys and reference values for B vitamins as well as homocysteine still must be established. Hence, further investigations are of great relevance.

Adolescent↗
PubMedDate not supplied

Maternal and fetal serum and red blood cell folate and vitamin B12 concentrations in pregnancies affected by neural tube defects.

In the present study maternal and fetal serum and red cell folate and vitamin B12 concentrations were determined in NTD affected and in control pregnancies. Fetal serum folate (p < 0.001) and red cell folate (p < 0.001) concentrations were significantly higher than maternal levels in the cases as well as in the controls. Maternal and fetal vitamin B12 concentrations did not differ significantly in both groups. There were also no significant differences in maternal and fetal vitamin concentrations in the peripheral blood between cases and controls. However, when a subgroup analysis was performed according to the type of NTD we found significant differences in fetal vitamin B12 status between anencephaly and spina bifida cases as well as between anencephaly cases and the controls.

Anencephaly↗