PubMed Health⌕ Search

Biomedical subjects

E Thiemann

Publications and source records attributed to E Thiemann.

8 recordsLinked to original sources
PubMed1991

Apolipoprotein A-I-containing lipoproteins in human umbilical cord blood. Relation to proapolipoprotein A-I and lecithin:cholesterol acyltransferase.

Lipids, apolipoproteins, lipoproteins, as well as lipoproteins containing both apo A-I and apo A-II (Lp A-I:A-II) or apo A-I but no apo A-II (Lp A-I), proapolipoprotein (proapo) A-I and the activity of lecithin:cholesterol acyltransferase (LCAT), were investigated in umbilical cord sera of 67 term human neonates (30 females and 37 males). Lp A-I and Lp A-I:A-II were present in umbilical cord sera with levels of 0.26 +/- 0.1 and 0.33 +/- 0.15 g/l, respectively. Furthermore, the absolute amount of proapo A-I was lower in cord blood than in adult plasma, but in view of the lower apo A-I levels in umbilical cord sera it comprised 10.48 +/- 3.86% of total apo A-I and was thus significantly higher than in adult plasma (7.1 +/- 0.9%). Proapo A-I was highly correlated with HDL cholesterol and apo A-I. Total serum LCAT activity was about 50% of adult plasma and was highly correlated with Lp A-I, but not with Lp A-I:A-II. We conclude that human umbilical cord serum contains both Lp A-I and Lp A-I:A-II particles and that the LCAT activity is predominantly related with the Lp A-I subfraction. The higher percentage in umbilical cord sera of proapo A-I may indicate a higher turnover of apo A-I or a lower activity of the proapo A-I cleaving enzyme which is still not identified.

Apolipoprotein A-I↗
PubMed1989

Polymorphism of apolipoprotein E influences levels of serum apolipoproteins E and B in the human neonate.

To gain more insight into the genetic vs. environmental influence of the apoE phenotypes on plasma lipoprotein variation we studied human umbilical cord sera at birth. Apolipoprotein E genetic phenotypes were determined in 110 individuals by immunoblotting and shown to be identical to the adult human isoforms with six phenotypes present and occurring at a similar frequency as reported previously for the adult population in the same area. Total serum cholesterol and triglyceride levels were low in the neonates and did not differ significantly between apoE phenotypes. On the other hand as in the adult, levels of apoE and B differed significantly between the phenotypes. ApoE was highest in individuals with the epsilon 2 allele and lowest in individuals expressing apoE4, and vice versa for apoB. We conclude that apoE phenotypes in human umbilical cord blood serum are already associated with pronounced differences in apoE and B levels in the newborn. The study demonstrates that the association of apoE and apoB levels with the apoE polymorphism occurs independently of significant enteral nutrition in the relatively constant in utero environment.

Apolipoproteins B↗
PubMed1988

Changes of apolipoprotein A-IV in the human neonate: evidence for different inductions of apolipoproteins A-IV and A-I in the postpartum period.

The levels, isoforms and distribution of apolipoprotein A-IV (apo A-IV) were investigated in 127 term human umbilical cord sera. In addition, apo A-IV levels and isoforms were determined on the 3rd (n = 82) and 6th (n = 68) day following parturition and compared to apo A-I concentrations. Levels of apo A-IV were low in umbilical cord serum (5.7 +/- 1.9 mg/dl) as compared to adult serum (17.6 +/- 4.8 mg/dl). No difference was found between male and female neonates. The serum distribution of apo A-IV closely resembled that seen in the adult human. Apo A-IV concentrations dramatically increased during the first week of life reaching levels of 13.4 +/- 4.1 mg/dl on day 3 and 16.7 +/- 3.4 mg/dl on day 6 post-partum. During this time apo A-I levels did not change significantly (81.0 +/- 16.5 mg/dl in cord serum, 75.3 +/- 10.6 mg/dl and 84.2 +/- 14.5 mg/dl on day 3 and 6, respectively). Cord serum already exhibited the major serum apo A-IV isoforms seen in the adult. Isofocusing of apo A-IV also identified the known genetic polymorphism of apo A-IV. Among 127 cord sera studied we identified 109 homozygote normal patterns, apo A-IV (1-1), 16 heterozygotes, apo A-IV (1-2) and 2 individuals homozygote for the variant peptide, apo A-IV (2-2). We provide evidence that apo A-IV and apo A-I are differently induced in the human neonate during the beginning of the feeding period.(ABSTRACT TRUNCATED AT 250 WORDS)

Apolipoprotein A-I↗