PubMed Health⌕ Search

Biomedical subjects

P Bührdel

Publications and source records attributed to P Bührdel.

At least 37 records · Page 2Linked to original sources
PubMed1985

Adenine therapy in Lesch-Nyhan syndrome.

In a 7-year-old patient with Lesch-Nyhan syndrome (LNS) the 15N excess frequency was determined in the excreted uric acid after oral application of 27 mg 15N glycine/kg body weight, using emission spectrometry. Incorporation of glycine into uric acid was considerably increased in untreated LNS in comparison with the control. This was due to the extremely increased endogenous de novo synthesis of purine. Allopurinol therapy caused only a gradual decrease of uric acid excretion. The pattern of purine excretion changed in favour of the better soluble oxipurines hypoxanthine and xanthine, by competitive inhibition of xanthine oxidase. In LNS, however, allopurinol had no uricostatic effect. Therapy with adenine is an alternative to influence the de novo synthesis. After adenine application a decrease of the cumulative 15N uric acid excretion occurs and the percentual proportion of 15N uric acid in total 15N excretion decreases. These changes are due to an inhibition of de novo purine biosynthesis. Adenine, however, must be applied in combination with allopurinol in order to avoid the formation of nephrotoxic 2,8-dioxiadenine by xanthine oxidase. Adenine therapy led to an improvement of the clinical course. No side-effects were observed.

Adenine↗
PubMed1982

[Activities of various enzymes in brown fat tissue of rabbits in the pre- and post-natal period].

Newborn rabbits have mainly brown or multilocular fat tissue. The activity of G-6-PDH shows a prenatal decrease. The G-6-PDH activity is clearly lower in postnatal as compared to the fetal period. This is due to the minor role of fatty acid synthesis with reduced fat storage during this time. The high capacity of glycolysis becomes apparent by the high activity of hexokinase and lactate dehydrogenase. The activity of both enzymes, however, shows only slight postnatal changes, so that HK and LDH in contrast to pyruvate kinase in the postnatal period apparently have no regulatory effect. The altogether high activity of the NADP specific isocitrate dehydrogenase indicates the high turnover rates in the Krebs cycle and suggests the adjustment of the metabolism to a high energy turnover.

Adipose Tissue, Brown↗
PubMed1982

[Carbohydrate metabolism in rabbit livers in the pre- and post-natal period].

Until the 25th day of gestation only traces of glycogen are present in the fetal liver of rabbits. Then, a steep rise can be observed until birth. The prenatal accumulation of glycogen protects the newborn against glucose deficiency after the sudden interruption of glucose supply after birth. Immediately after birth the blood glucose level falls in newborn rabbits. With insufficient gluconeogenesis stabilization during the first hours of postnatal life depends on the extent of the glucogen storage in the liver. The HK of the rabbit liver shows a higher activity during the fetal period as compared to the postnatal period. During postnatal life the relative proportion of the HK of the phosphorylation of glucose shows a consistent decrease; and in adult animals this function is nearly entirely taken over by the GK. In accordance with the occurrence of a GK activity the glycogen content shows a steep increase in the rabbit liver after the 9th day of life. The high PK activity of the fetal liver suggests a high glycolytic activity. The decrease in activity during the first days of life favours the overshooting gluconeogenesis of this phase and thus might contribute to the stabilization of the glucose blood level. The rise of activity at the 9th day of life shows a nearly synchronous behaviour in comparison with the development of the GK activity. Due to the change of food with introduction of solid nutrition rich in carbohydrates the PK shows a new rise after the 21st day of postnatal life. Whereas the activity of LDH of the fetal liver of rabbits is of the same magnitude as that of adult animals, there is a perinatal increase of activity with a peak at the 9th day of postnatal life. This step-up of activity is regarded as an adaptation phenomenon by de novo synthesis of enzyme protein.

Animals↗
PubMed1979

[Significance of early detection and early treatment of the development of children with phenylketonuria].

The amino acid l-phenylalanine (PA) accounts for 3-6 percent of all food proteins. Its breakdown is mainly through change into tyrosine. This irreversible metabolic step which makes PA an essential amino acid occurs in the liver and is catalyzed by PA-hydroxylase. In the autosome-recessive phenylketonuria syndrome (PKU, medium incidence rate 1:10,000) there is no PA-hydroxylase activity in the hepatic tissue. Infants suffering from PKU are born without any visible damage, but the untreated disease leads to irreversible brain injury. In the GDR legislation for early screening has been in force since 1971, so that the disease is recognized in all new-born babies. Brain damage can be prevented by dietetic treatment which starts during the first month but not later than the second month of life. The results of examinations performed on 107 infants suffering from PKU, with different onsets of dietetic treatment, underline the fundamental importance of early recognition and treatment for optimal development.

Child↗
PubMed1978

Postnatal development of rats born preterm and postterm. I. Body weight.

Litters with 3 preterm, 3 term and 3 postterm littermates have been fed by one mother each. Fetal body weight continues to increase in utero if the normal gestational period is extended by 1 day. But this intrauterine weight gain is smaller than the postnatal weight gains of term rats of the same conceptional ages. While the body weights of term and postterm rats increase rapidly immediately after birth, there is a lag phase of 3 days in preterm animals. This delay in weight gain is not caught up during a period of 30 postnatal days. This appears to be due to malnutrition in the early postnatal period. After the 20th day of life, the weight gain markedly increases in all groups, indicating the effect of supplemental feeding in the weaning period.

Animal Nutritional Physiological Phenomena↗
PubMed1978

The postnatal development of rats born preterm and postterm. II. Liver, brain, heart and kidneys.

Groups of 3 preterm (duration of gestation 22 days), 3 term (23 days), and 3 postterm (24 days) rats have been fed together by 1 mother rat. The postnatal growth of liver, brain, heart and kidney has been studied up to the 30th day of life. The postnatal loss of water shows good correlation with the maturation of each organ. The postnatal loss of water is marked in brain and kidneys, but only slight in liver and heart. The pronounced growth spurt of the brain at the about 10th day of life is probably due to the opening of the eyes. The growth spurt of the liver at the 15th day may be due to the supplementary food at the time of weaning. The effect of intrauterine undernutrition in postterm rats is most strikingly demonstrated in the liver. Postnatal undernutrition in preterm rats causes a retardation of growth of the liver and kidneys.

Animals↗
PubMed1978

[Therapeutic problems in the "short-bowel-syndrome" (author's transl)].

The authors report on 6 children with short-bowel-syndrome. The expectancy of life of the patients depends on the mucosal surface of the residual intestine and on the degree of adaption. After removal of larger proportions of the intestine, nutrition should be started parenterally and followed by an early but cautious oral feeding. The administration must be distributed continuously over the day. At first carbohydrates are given as monosaccharides, fats as M. C. T. and proteins as amino acid mixtures. Carrot soup has proved useful as a water-binding substance for the improvement of stool consistency. An anabolic condition of the metabolism should be maintained. Therapy with cholestyramin is indicated in chologenic diarrhoea. Substitution of vitamins, especially vitamin B12 is very important after resection of the ileum.

Amino Acids↗
PubMed1975

[Morphology of the rat placenta in experimental, hormone-induced, prolonged pregnancy. II. Plancenta in intrauterine macerated dead rat fetuses].

In course of overdue pregnancy in rats, produced by application of synthetic gestagens the intrauterine death rate rises, when the gestation time is more than 23 days. Placentas of 47 macereted fetus rats we have investigated. The pathologic-anatomical picture of the placenta characterized by collaps and following regression of the peripheral fetal blood system. Furthermore, there are narrowing processes in great fetal vessels. In the maternal sinus occurs fibrin. The labyrinth of the placenta inclines by production of collagen fibers to a homogenous structure. The trophoblastic epithel is less differentiated. These findings in rat placentas we have compared with those in human placentas in cases of fetal maceration. The worth of these changes for differentiation of intravital against postmortal regressive processes is evident.

Animals↗