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Bile Pigment
The Experts below are selected from a list of 93 Experts worldwide ranked by ideXlab platform
Peter L M Jansen – 1st expert on this subject based on the ideXlab platform
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the differential diagnosis of crigler najjar disease types 1 and 2 by Bile Pigment analysis
Gastroenterology, 1991Co-Authors: M Sinaasappel, Peter L M JansenAbstract:Phenobarbital response, Bile Pigment composition, and the fractional biliary excretion ratio of bilirubin were studied in nine children with Crigler—Najjar disease. In five children, serum bilirubin levels decreased during phenobarbital treatment by 26% or more and the Pigment composition in Bile changed with a decrease in the proportion of unconjugated bilirubin from 33% ± 12% to 13% ± 1% and an increase in monoconjugates and diconjugates from 57% ±14% and 10% ± 2%, respectively, to 72% ± 4% and 16% ± 3%. In four children, serum bilirubin levels did not change significantly during phenobarbital treatment. In these patients, Bile Pigments comprised 91% ± 10% unconjugated bilirubin, 9% ± 11% monoconjugates, and 1% ± 1% diconjugates. On the basis of these differences, the former group can be classified as having type 2 Crigler—Najjar disease and the latter, type 1. Bile Pigment analysis in parents of patients with Crigler—Najjar disease showed an increased proportion of monoconjugates in at least one of the partners in three of four couples tested, despite normal serum bilirubin levels. Serum bilirubin levels were about the same in type 1 and 2 patients and amounted to 236 ± 62 μmol/L and 214 ± 82 μmol/L, respectively. In addition the fractional bilirubin excretion ratio, calculated as the ratio ([bilirubin in Bile]/[bilirubin in serum])/([Bile acid in Bile]/[Bile acid in serum]) could not differentiate between these two groups. However, there was a 10-fold and 100-fold difference of this ratio between patients with Crigler—Najjar disease and those with Gilbert’s syndrome and between patients with Crigler—Najjar disease and controls. The fractional bilirubin excretion ratio proved an excellent tool to differentiate between Gilbert’s syndrome and Crigler—Najjar disease, whereas Crigler—Najjar disease types 1 and 2 could be differentiated on the basis of Bile Pigment analysis.
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The differential diagnosis of Crigler—Najjar disease, types 1 and 2, by Bile Pigment analysis
Gastroenterology, 1991Co-Authors: M Sinaasappel, Peter L M JansenAbstract:Phenobarbital response, Bile Pigment composition, and the fractional biliary excretion ratio of bilirubin were studied in nine children with Crigler—Najjar disease. In five children, serum bilirubin levels decreased during phenobarbital treatment by 26% or more and the Pigment composition in Bile changed with a decrease in the proportion of unconjugated bilirubin from 33% ± 12% to 13% ± 1% and an increase in monoconjugates and diconjugates from 57% ±14% and 10% ± 2%, respectively, to 72% ± 4% and 16% ± 3%. In four children, serum bilirubin levels did not change significantly during phenobarbital treatment. In these patients, Bile Pigments comprised 91% ± 10% unconjugated bilirubin, 9% ± 11% monoconjugates, and 1% ± 1% diconjugates. On the basis of these differences, the former group can be classified as having type 2 Crigler—Najjar disease and the latter, type 1. Bile Pigment analysis in parents of patients with Crigler—Najjar disease showed an increased proportion of monoconjugates in at least one of the partners in three of four couples tested, despite normal serum bilirubin levels. Serum bilirubin levels were about the same in type 1 and 2 patients and amounted to 236 ± 62 μmol/L and 214 ± 82 μmol/L, respectively. In addition the fractional bilirubin excretion ratio, calculated as the ratio ([bilirubin in Bile]/[bilirubin in serum])/([Bile acid in Bile]/[Bile acid in serum]) could not differentiate between these two groups. However, there was a 10-fold and 100-fold difference of this ratio between patients with Crigler—Najjar disease and those with Gilbert’s syndrome and between patients with Crigler—Najjar disease and controls. The fractional bilirubin excretion ratio proved an excellent tool to differentiate between Gilbert’s syndrome and Crigler—Najjar disease, whereas Crigler—Najjar disease types 1 and 2 could be differentiated on the basis of Bile Pigment analysis.
Thomas M Laue – 2nd expert on this subject based on the ideXlab platform
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influence of phosphatidylcholine and calcium on self association and Bile salt mixed micellar binding of the natural Bile Pigment bilirubin ditaurate
Biochemistry, 2015Co-Authors: Michael W Neubrand, Martin C Carey, Thomas M LaueAbstract:Recently [Neubrand, M. W., et al. (2015) Biochemistry 54, 1542–1557], we determined a concentration-dependent monomer–dimer–tetramer equilibrium in aqueous bilirubin ditaurate (BDT) solutions and explored the nature of high-affinity binding of BDT monomers with monomers and micelles of the common taurine-conjugated Bile salts (BS). We now investigate, employing complementary physicochemical methods, including fluorescence emission spectrophotometry and quasi-elastic light scattering spectroscopy, the influence of phosphatidylcholine (PC), the predominant phospholipid of Bile and calcium, the major divalent biliary cation, on these self-interactions and heterointeractions. We have used short-chain, lyso and long-chain PC species as models and contrasted our results with those of parallel studies employing unconjugated bilirubin (UCB) as the fully charged dianion. Both Bile Pigments interacted with the zwitterionic headgroup of short-chain lecithins, forming water-soluble (BDT) and insoluble ion-pair comple…
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self assembly of aqueous bilirubin ditaurate a natural conjugated Bile Pigment to contraposing enantiomeric dimers and m and p tetramers and their selective hydrophilic disaggregation by monomers and micelles of Bile salts
Biochemistry, 2015Co-Authors: Michael W Neubrand, Martin C Carey, Thomas M LaueAbstract:The solution behavior of bilirubin ditaurate (BDT), the first naturally occurring conjugated Bile Pigment to be physically and chemically characterized, was assessed in aqueous solution and in monomeric and micellar solutions of common taurine-conjugated Bile salts (BS). Analytical ultracentrifugation revealed that BDT self-associates in monomer–dimer equilibria between 1 and 500 μM, forming limiting tetramers at low millimolar concentrations. Self-association was enthalpically driven with ΔG values of ≈5 kcal/mol, suggesting strong hydrophobic interactions. Added NaCl and decreases in temperature shifted the oligomerization to lower BDT concentrations. On the basis of circular dichroism spectra and the limiting size of the self-aggregates, we infer that the tetramers are composed of 2P(+) and 2M(−) enantiomeric BDT pairs in “ridge-tile” conformations interacting in a “double-bookend” structure. With added monomeric BS, blue shifts in the UV–vis spectra and tight isosbestic points revealed that BDT/BS het…
M Sinaasappel – 3rd expert on this subject based on the ideXlab platform
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the differential diagnosis of crigler najjar disease types 1 and 2 by Bile Pigment analysis
Gastroenterology, 1991Co-Authors: M Sinaasappel, Peter L M JansenAbstract:Phenobarbital response, Bile Pigment composition, and the fractional biliary excretion ratio of bilirubin were studied in nine children with Crigler—Najjar disease. In five children, serum bilirubin levels decreased during phenobarbital treatment by 26% or more and the Pigment composition in Bile changed with a decrease in the proportion of unconjugated bilirubin from 33% ± 12% to 13% ± 1% and an increase in monoconjugates and diconjugates from 57% ±14% and 10% ± 2%, respectively, to 72% ± 4% and 16% ± 3%. In four children, serum bilirubin levels did not change significantly during phenobarbital treatment. In these patients, Bile Pigments comprised 91% ± 10% unconjugated bilirubin, 9% ± 11% monoconjugates, and 1% ± 1% diconjugates. On the basis of these differences, the former group can be classified as having type 2 Crigler—Najjar disease and the latter, type 1. Bile Pigment analysis in parents of patients with Crigler—Najjar disease showed an increased proportion of monoconjugates in at least one of the partners in three of four couples tested, despite normal serum bilirubin levels. Serum bilirubin levels were about the same in type 1 and 2 patients and amounted to 236 ± 62 μmol/L and 214 ± 82 μmol/L, respectively. In addition the fractional bilirubin excretion ratio, calculated as the ratio ([bilirubin in Bile]/[bilirubin in serum])/([Bile acid in Bile]/[Bile acid in serum]) could not differentiate between these two groups. However, there was a 10-fold and 100-fold difference of this ratio between patients with Crigler—Najjar disease and those with Gilbert’s syndrome and between patients with Crigler—Najjar disease and controls. The fractional bilirubin excretion ratio proved an excellent tool to differentiate between Gilbert’s syndrome and Crigler—Najjar disease, whereas Crigler—Najjar disease types 1 and 2 could be differentiated on the basis of Bile Pigment analysis.
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The differential diagnosis of Crigler—Najjar disease, types 1 and 2, by Bile Pigment analysis
Gastroenterology, 1991Co-Authors: M Sinaasappel, Peter L M JansenAbstract:Phenobarbital response, Bile Pigment composition, and the fractional biliary excretion ratio of bilirubin were studied in nine children with Crigler—Najjar disease. In five children, serum bilirubin levels decreased during phenobarbital treatment by 26% or more and the Pigment composition in Bile changed with a decrease in the proportion of unconjugated bilirubin from 33% ± 12% to 13% ± 1% and an increase in monoconjugates and diconjugates from 57% ±14% and 10% ± 2%, respectively, to 72% ± 4% and 16% ± 3%. In four children, serum bilirubin levels did not change significantly during phenobarbital treatment. In these patients, Bile Pigments comprised 91% ± 10% unconjugated bilirubin, 9% ± 11% monoconjugates, and 1% ± 1% diconjugates. On the basis of these differences, the former group can be classified as having type 2 Crigler—Najjar disease and the latter, type 1. Bile Pigment analysis in parents of patients with Crigler—Najjar disease showed an increased proportion of monoconjugates in at least one of the partners in three of four couples tested, despite normal serum bilirubin levels. Serum bilirubin levels were about the same in type 1 and 2 patients and amounted to 236 ± 62 μmol/L and 214 ± 82 μmol/L, respectively. In addition the fractional bilirubin excretion ratio, calculated as the ratio ([bilirubin in Bile]/[bilirubin in serum])/([Bile acid in Bile]/[Bile acid in serum]) could not differentiate between these two groups. However, there was a 10-fold and 100-fold difference of this ratio between patients with Crigler—Najjar disease and those with Gilbert’s syndrome and between patients with Crigler—Najjar disease and controls. The fractional bilirubin excretion ratio proved an excellent tool to differentiate between Gilbert’s syndrome and Crigler—Najjar disease, whereas Crigler—Najjar disease types 1 and 2 could be differentiated on the basis of Bile Pigment analysis.