Manganese balance studies in infants after operations on the heart.

Manganese balance studies have been performed on 16 infants, aged 3 days to 8 months, in the period following operation for the correction of congenital heart defects. Samples were analyzed by flameless atomic absorption spectroscopy or by solvent extraction with 8-hydroxyquinoline followed by flame atomic absorption spectroscopy. A higher manganese content was found in either whole blood (710 +/- 320 nmole X litre-1) or purified plasma protein (1130 +/- 770 nmole X litre-1) compared with fresh frozen plasma (215 +/- 35 nmole X litre-1) used in intravenous drips.

Secretion of plasminogen activator by the human macrophage-like cell line, GCT: separation from colony-stimulating and erythropoiesis-enhancing activities.

The human macrophage-like cell line, GCT, elaborates monokines such as colony-stimulating activity (CSA) and erythropoiesis-enhancing activity (EEA) which stimulate the growth of primitive blood progenitors in culture. These cells also secrete a fibrinolysis activator (FA), which can be identified if cells are cultured in serum-free medium. FA was found to have a similar molecular weight to CSA and EEA by gel filtration but could be separated from them by ion exchange chromatography.

Hydrophobic adsorption chromatography of colony-stimulating activities and erythroid-enhancing activity from the human monocyte-like cell line, GCT.

The human cell line, GCT, secretes hemopoietins into serum-free culture medium. The conditioned medium contains activities that stimulate neutrophil-monocyte, macrophage, eosinophil, and erythroid colony growth in human marrow cultures. We have used hydrophobic adsorption chromatography to separate a neutrophil-monocyte colony-stimulating factor (CSF) from the other colony-stimulating activities.

Autostimulation of growth by human myelogenous leukemia cells (HL-60).

We have studied the effects of medium conditioned by the human progranulocytic leukemia cell line, HL-60, on the subsequent growth of new inocula of HL-60 cells. When HL-60 cells were cultured at high cell density, optimal growth rate occurred in liquid suspension and confluent colony growth was observed in viscous medium without the addition of conditioned medium. However, when cells were cultured at lower cell density, growth rate was reduced and colony growth was nil unless conditioned medium from HL-60 culture was added.

Plasmic degradation of crosslinked fibrin. Characterization of new macromolecular soluble complexes and a model of their structure.

Crosslinked fibrin was digested by plasmin, and three soluble complexes larger than DD/E were purified and characterized. After gel filtration chromatography, the purified complexes were shown to have molecular weights of 465,000, 703,000, and 850,000, as determined by equilibrium sedimentation. Each of the complexes was dissociated into two or more fragments by SDS-polyacrylamide gel electrophoresis.

Separation of peptides and amino acids by ion-exchange chromatography of their copper complexes.

The method of separating peptides and amino acids using their copper (II) complexes has been reexamined by studying model compounds. A marked improvement in the separation was achieved on DEAE Sephadex columns by variation of the ionic strength of the eluting buffers. The use of the method is illustrated by an examination of a protein hydrolysate used in intravenous feeding (Aminosol).

Excretion of polyamines by children with Beckwith's syndrome.

The urinary excretion of the polyamines--putrescine, spermidine, and spermine--was measured in 7 children with Beckwith's syndrome. Putrescine excretion was raised and spermidine excretion reduced. The raised putrescine and the low spermidine ratios were highly significant.

The excretion of alkaline ribonuclease by children undergoing surgery.

The excretion of alkaline ribonuclease has been measured in the urine of two groups of children after major operations. The excretion was significantly increased in all patients after open operations on the heart and in many of those who were operated on soon after birth for anomalies in the intestine. It is suggested that these elevations may indicate a disturbance of pancreatic function.

Metabolism of nicotinic acid in children with burns and scalds.

The excretions of two metabolites of nicotinic acid, N1-methylnicotinamide and N1-methyl-2-pyridone-5-carboxamide have been measured at varying times after injury in a group of 27 burned or scalded children. Compared with control patients the excretions of both of these metabolites were significantly raised after injury, which suggests that the utilisation of nicotinic acid is increased.

Plasminogen activator from human embryonic kidney cell cultures. Evidence for a proactivator.

The nature of the trypsin-activatable plasminogen activator produced by kidney cell cultures (Bernik, M.B (1973), J. Clin.