TY  - JOUR
A1  - Nagl, Britta
A1  - Loui, Andrea
A1  - Raila, Jens
A1  - Felderhoff-Mueser, Ursula
A1  - Obladen, Michael
A1  - Schweigert, Florian J.
T1  - Urinary vitamin A excretion in very low birth weight infants
N2  - Vitamin A (VA) deficiency in very low birth weight (VLBW) infants is associated with an increased risk for disorders related to kidney and lung maturation and function. VA losses through increased urinary retinol (ROH) excretion might contribute to this deficiency risk. The mechanism accounting for ROH loss in the urine has not yet been clarified. The aim of this study was to assess the excretion of ROH, retinol-binding protein 4 (RBP4) and transthyretin (TTR) in urine from VLBW infants in comparison with that in term infants in relation to kidney function. Urine specimens were collected from 15 VLBW infants (birth weight < 1,500 g) as well as from 20 term infants during the first 2 days after birth. ROH in urine was detectable in 14 of the 15 VLBW infants at a median concentration of 234 nmol/g creatinine. In the group of term infants, 17 of the 20 excreted ROH, but at an approximately five-times lower concentration (P<0.001). Excretion of RBP4 and TTR was also much higher in VLBW infants (both P<0.001). The urinary ROH excretion in VLBW infants may be related to the impaired tubular handling of its carrier proteins RBP4 and TTR. Thus, ROH excretion might contribute to an increased risk of VA deficiency, especially in VLBW infants.
Y1  - 2009
UR  - http://www.springerlink.com/content/100382
U6  - https://doi.org/10.1007/s00467-008-0965-0
SN  - 0931-041X
ER  - 
TY  - JOUR
A1  - Frey, Simone K.
A1  - Henze, Andrea
A1  - Nagl, Britta
A1  - Raila, Jens
A1  - Scholze, Alexandra
A1  - Tepel, Martin
A1  - Schweigert, Florian J.
A1  - Zidek, Walter
T1  - Effect of renal replacement therapy on retinol-binding protein 4 isoforms
N2  - Background: Retinol-binding protein 4 (RBP4) levels are elevated in the serum of patients with kidney dysfunction. We recently showed that RBP4 isoforms including apo-RBP4 (RBP4 not bound to retinol) and RBP4 truncated at the C-terminus (RBP4-L, RBP4-LL) are increased in the serum of patients with kidney diseases but not in serum of patients with various liver diseases. The aim of this study was to investigate the effect of renal replacement therapy on RBP4 isoforms. Methods: We investigated serum levels of RBP4, apo-RBP4, holo-RBP4, RBP4-L, RBP4-LL, retinol and transthyretin (TTR) in 18 hemodialysis (HD) patients, 30 patients after renal transplantation (RTx) and in 35 healthy controls. RBP4 and TTR levels were measured by enzyme-linked immunosorbent assay, apo- and holo-RBP4 by native electrophoresis, retinol by high performance liquid chromatography and RBP4-L and RBP4-LL were analyzed by mass spectrometry. Results: HD and RTx patients had elevated RBP4, apo-RBP4 and RBP4-LL levels compared to controls. RTx patients had elevated amounts of RBP4-L compared to controls and elevated RBP4 and apo-RBP4 levels compared to HD patients. Conclusion: The results demonstrate a strong correlation between kidney function and RBP4 isoforms and provide data for investigating the relation of RBP4 and insulin resistance in these patients.
Y1  - 2009
UR  - http://www.sciencedirect.com/science/journal/00098981
U6  - https://doi.org/10.1016/j.cca.2008.11.008
SN  - 0009-8981
ER  - 
TY  - JOUR
A1  - Tschumi, Sibylle
A1  - Nagl, Britta
A1  - Simonetti, Giacomo Domenico
A1  - von Vigier, R.
A1  - Uehlinger, Dominik
A1  - Lauterburg, Bernhard
A1  - Utsch, Boris
T1  - Symptomatic pseudotumor cerebri : evidence for toxic vitamin A levels in patients with chronic renal insufficiency?
Y1  - 2009
UR  - http://www.springerlink.com/content/100382
U6  - https://doi.org/10.1007/s00467-009-1132-y
SN  - 0931-041X
ER  -