MicroRNAs (miRNAs) are short, 22–25 nucleotide long transcripts that may suppress entire signaling pathways by interacting with the 3’-untranslated region (3’-UTR) of coding mRNA targets, interrupting translation and inducing degradation of these targets. The long 3’-UTRs of brain transcripts compared to other tissues predict important roles for brain miRNAs. Supporting this notion, we found th...

BACKGROUND We applied untargeted mass spectrometry-based metabolomics to the diseases methylmalonic acidemia (MMA) and propionic acidemia (PA). METHODS We used a screening platform that used untargeted, mass-based metabolomics of methanol-extracted plasma to find significantly different molecular features in human plasma samples from MMA and PA patients and from healthy individuals. Capillary...

BACKGROUND Analysis of carnitine and acylcarnitines by tandem mass spectrometry (MS/MS) has limitations. First, preparation of butyl esters partially hydrolyzes acylcarnitines. Second, isobaric nonacylcarnitine compounds yield false-positive results in acylcarnitine tests. Third, acylcarnitine constitutional isomers cannot be distinguished. METHODS Carnitine and acylcarnitines were isolated b...

492 CLINICAL CHEMISTRY, Vol.31, No. 3, 1985 1. Fishlock RC, Bieber LL, Snoswell AM. Sources of error in determinations of carnitine and acylcarnitine in plasma. Clin Chem 30, 316-318 (1984). 2. Brass EP, Hoppel CL. Carnitine metabolism in the fasting rat. J Biol Chem 253, 2688-2693 (1978). 3. Genuth SM, Hoppel CL. Plasma and urine carnitine in diabetic ketosis. Diabetes 28, 1083-1087 (1978). 4....

By their very nature, rare inborn errors of metabolism challenge the generation and application of evidence-based medicine. • On the basis of limited research evidence as well as consensus, newborn screening for select metabolic disorders, including phenylketonuria, medium-chain acyl CoA dehydrogenase deficiency, and glutaric acidemia type I, may improve long-term outcomes for affected children...

OBJECTIVE To describe the influence that gestational age and chronological age have on amino acid and acylcarnitine profiles in an at-risk population of premature infants. METHODS Metabolic profiles (15 amino acids and 35 acylcarnitines) were obtained by using standard newborn techniques on infants born between 23 and 31 completed weeks of gestation. The profiles were drawn within the first 2...

BACKGROUND It has been reported that hemodialysis patients have elevated plasma acylcarnitine concentrations, which correlates to reduced red blood cell integrity. It has also been reported that the supplementation of L-carnitine for these patients improves anemia, glucose metabolism and muscle function, but the mechanism of these relationships remains unknown. We hypothesized that the cause of...

The concentrations of malonyl-CoA, citrate, ketone bodies and long-chain acylcarnitine were measured in freeze-clamped liver samples from fed or starved normal, partially hepatectomized or sham-operated rats. These parameters were used in conjunction with measurements of the concentration of plasma non-esterified fatty acids and the rates of hepatic lipogenesis to obtain correlations between ra...