Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A detailed study of the qualitative and quantitative composition of bile acids in human fetal gallbladder bile is described. Bile was collected during early gestation (weeks 16-19) and analyzed by gas chromatography and mass spectrometry, fast atom bombardment ionization mass spectrometry, and high performance liquid chromatography. Bile acids were separated into different conjugate groups by chromatography on the lipophilic anion exchange gel, diethylaminohydroxypropyl Sephadex LH-20. Quantitatively more than 80% of the bile acids were secreted into bile conjugated to taurine. Unconjugated bile acids and glycine conjugates accounted for 5-10% of the total biliary bile acids. Bile acid sulfates were present only in trace amounts indicating that quantitatively sulfation is not an important pathway in bile acid metabolism during development. Total biliary bile acid concentrations were low (0.1-0.4 mM) when compared to reported values for adult bile (greater than 10 mM). Chenodeoxycholic acid was the major biliary bile acid and exceeded cholic acid concentrations by 1.43-fold indicating either a relative immaturity in 12 alpha-hydroxylase activity during early life or a dominance of alternative pathways for chenodeoxycholic acid synthesis. A relatively large proportion of the biliary bile acids comprised metabolites not found in adult bile. The presence of relatively high proportions of hyocholic acid (often greater than cholic acid) and several 1 beta-hydroxycholanoic acid isomers indicates that C-1 and C-6 hydroxylation are important pathways in bile acid synthesis during development. We describe, for the first time, evidence for the existence of a C-4 hydroxylation pathway in the metabolism of bile acids, which may be unique to early human development. Mass spectrometry was used to confirm the identification of 3 alpha,4 beta,7 alpha-trihydroxy-5 beta-cholanoic and 3 alpha,4 beta-dihydroxy-5 beta-cholanoic acids. Quantitatively, these C-4 hydroxylated bile acids accounted for 5-15% of the total biliary bile acids of the fetus, suggesting that C-4 hydroxylation is quantitatively an important pathway in the bile acid metabolism during early life.
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PMID:Hepatic bile acid metabolism during early development revealed from the analysis of human fetal gallbladder bile. 318 6

Using analytical techniques, which included capillary column gas-liquid chromatography and mass spectrometry, detailed bile acid profiles were obtained for 24 fetal bile samples collected after legal abortions were performed between the 14th and 20th wk of gestation. Qualitatively, the bile acid profiles of all fetal bile samples were similar. The predominant bile acids identified were chenodeoxycholic and cholic acid. The presence of small but variable amounts of deoxycholic acid and traces of lithocholic acid suggested placental transfer of these bile acids from the maternal circulation. 3 beta-Hydroxy-5-cholenoic acid was detected at higher levels than lithocholic acid. A conspicuous feature of the profiles was the presence of bile acids with hydroxyl groups at positions C-1 and C-6, and one other nuclear position of unknown origin, indicating fetal hepatic synthesis via pathways different from those normally seen in the adult. Quantitatively total biliary bile acid concentrations were extremely low (less than 0.05 mM) before wk 17 of gestation, but thereafter concentrations markedly increased reflecting a possible surge in bile acid synthesis; however, the ratio of cholic:chenodeoxycholic acids remained relatively constant over this period (mean +/- SD = 0.85 +/- 0.36) and different from that reported for the healthy newborn (ca. 2.5) and adult (ca. 1.6). These data indicate an immaturity in hepatic 12 alpha-hydroxylation of bile acids during early development and may explain why other pathways, in particular 1 beta and 6 alpha-hydroxylation, are activated at this stage of life.
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PMID:Biliary bile acid composition of the human fetus in early gestation. 382 1

The 24h urinary bile acid excretion was prospectively studied during the neonatal period in healthy, fully breastfed, premature and full-term infants. The urinary bile acids were identified by gas-liquid chromatography (GLC)-mass spectrometry and quantified by GLC. The excretion of bile acids in urine increased after birth, reaching maximum levels by the 3-4th day. Taurine conjugates predominated and the excretion of bile acid sulphates was remarkably low. Cholic acid and atypical bile acids were the main bile acids in urine during the first week. Tetrahydroxylated bile acids carrying hydroxyl groups at C-1, C-2 and C-6 were common, and also other 1- and 6-hydroxylated bile acids, including hyocholic and hyodeoxycholic acids. Three tentatively identified 4-hydroxylated bile acids, including one ketonic bile acid, were also found. Ketonic bile acids constituted an average of 16% of total urinary bile acids during the first week. Unsaturated bile acids were scantily found only during the first days. The excretion of atypical bile acids decreased to 1 month of age, parallel with the total bile acid excretion. The data support earlier hypothesis of a physiological cholestasis in the newborn. Atypical hydroxylated and ketonic bile acids, as well as cholic acid, constituted the major part of the urinary bile acids. The persistent atypical pattern of bile acids in urine during the first month of life indicates a longer period of immaturity of bile acid metabolism in healthy infants than previously described.
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PMID:The urinary bile acid excretion in healthy premature and full-term infants during the neonatal period. 817 Dec 65

The use of spinal implants in the pediatric population is controversial in terms of skeletal immaturity. The authors present the case of a 12-year-old boy with displaced Type III odontoid fracture, successfully treated by direct screw fixation. Fractures defined as Type II and Type III according to the classification by Anderson and D'Alonzo are instable spinal injuries. Type III fractures generally heal when treated conservatively. In certain circumstances, like displaced fractures or patients refusing long-term external immobilization, Type III fractures are treated surgically. A 12-year-old boy had neck injury caused by a bike accident. His main symptoms were neck pain and limitation of neck movements. Displaced Type III odontoid fracture was diagnosed. The authors treated this lesion surgically by screw fixation in order to correct displacement and to preserve the normal range of head motion. Fixation was performed by means of a single cannulated screw. Healing of the fracture was confirmed by roentgenograms done at follow-up examinations. The range of motion of the cervical spine examined 6 months after operation was normal. Direct anterior screw fixation was an effective method for treating displaced Type III odontoid fracture in a child. The rotatory motion between C-1 and C-2 was preserved.
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PMID:[Direct fixation of the odontoid fracture in a child]. 1538 60