Biomedical subjects

J C Philcox

Publications and source records attributed to J C Philcox.

39 records · Page 3Linked to original sources

PubMed1984

Fasting and non-fasting serum amino acid values in three home parenteral nutrition patients: a comparison between Synthamin 17R and vamin N 7%R.

Serum amino acid concentrations were measured during the fasting and non-fasting stages of nutrition in three home parenteral nutrition patients who received their nitrogen requirement as Synthamin 17R for 12 months then Vamin N 7%R for 12 months. When the patients received Synthamin 17R, the fasting serum amino acid values revealed consistently elevated levels of glycine, phenylalanine, methionine and alanine and low levels of leucine, iso-leucine, valine, lysine, histidine, cystine and serine. When the patients received Vamin N 7%R, the fasting serum amino acid levels showed consistently elevated levels of proline, phenylalanine, glutamate, alanine, cystine and valine and low levels of arginine. Many of the serum amino acid abnormalities observed reflected the differences in the amino acid profiles of Vamin N 7%R and Synthamin 17R when compared with a normal diet.

Adult↗

PubMed1983

Preparation and characterization of a human serum matrix suitable for quality control or reference materials.

We describe the preparation of a human serum based matrix suitable for inclusion in long-term control materials. The procedure entails the removal of cells, fibrin and lipoproteins from blood to produce a clear, stable material which has been stored frozen at -70 degrees C for up to 14 mth without any apparent deterioration. When incorporated into a quality control material, storage at 4 degrees and -20 degrees C may cause a change in several unstable constituents, but the material remains optically clear. A noticeable reduction in lipoprotein as a result of the preparative procedure is probably responsible for the continued clarity of the matrix. The nature of the matrix has been examined by polyacrylamide gel electrophoresis and does not reveal any unusual protein bands, whereas commercially available materials when similarly examined often reveal protein bands not present in normal serum. The matrix has been used to prepare control material for the Chemical Pathology Quality Assurance Programme Group of the Royal College of Pathologists of Australasia/Australian Association of Clinical Biochemists.

Blood Chemical Analysis↗

PubMedDate not supplied

Serum amino acid concentrations in patients receiving total parenteral nutrition with an amino acid plus dextrose mixture.

The results of monitoring the serum amino acid concentrations during three infusion regimens using a 5:4 mixture of 70% glucose and the synthetic L-amino acid solution, Synthamin 17 (Travasol) are reported. Twelve stabilized patients received continuous total parenteral nutrition (TPN), eight of whom were subsequently placed on a second regimen of cyclical feeding. A separate group of five patients was infused with amino acids, both with and without simultaneous glucose. The serum amino acid concentrations indicated that the supply of valine, leucine, isoleucine, lysine, and histidine, and the synthesis of taurine from the infused methionine was suboptimal, particularly if the period of TPN was prolonged. The synthesis of tyrosine from phenylalanine appeared to be inversely proportional to the infusion rate of the TPN mixture, in particular the glucose component, resulting in depressed tyrosine and increased phenylalanine concentrations in serum during continuous iv nutrition. Cyclical infusions, on the other hand, permitted the tyrosine and phenylalanine concentrations to return to normal during the noninfusion stage of the cycle. Amino acid measurements enabled us to design an amino acids additive mixture which normalized the serum concentrations in three long-term home parenteral nutrition patients. As a result of these investigations serum amino acid measurements are used routinely to monitor the efficacy of TPN and accommodate any specific amino acid requirements of individual patients.

Adult↗