Expression, purification, and characterization of BsSco, an accessory protein involved in the assembly of cytochrome c oxidase in Bacillus subtilis.

The studies described here were performed to characterize further the plasma membrane associated protein BsSco, which is the product of the gene ypmQ, in Bacillus subtilis. BsSco is a member of the Sco family of proteins found in the inner mitochondrial membrane of yeast and humans and implicated as an accessory protein in the assembly of the Cu(A) site of cytochrome c oxidase. We have cloned the gene expressing BsSco, placed a six-histidine tag on its C-terminus, and over-expressed this protein in B.

Contrasted pollen capture mechanisms in Phyllocladaceae and certain Podocarpaceae (Coniferales).

Comparative study shows that Phyllocladus and representative Podocarpaceae differ in the mechanism by which pollen is introduced into the pollen chamber and onto the apex of the nucellus ("pollen capture"). Both types involve a pollination drop, but only in Podocarpaceae is it consistently inverted and in contact with adjacent surfaces. Phyllocladus has functionally nonsaccate pollen (although a vestigial saccus has been claimed); its pollen is wettable and sinks in water.

Serum glutathione S-transferase B1 activity as an index of liver function in cystic fibrosis.

Aims: To evaluate serum glutathione S-transferase B1 (GST B1), a highly sensitive test of hepatocellular function, as a means of identifying liver disease in patients with cystic fibrosis (CF).

Methods: The presence of liver disease was sought over a three year period in 60 children with CF, using a combination of clinical assessment, ultrasound examination, conventional biochemical tests of liver function (LFTs), and measurement of GST B1.

Results: Reference ranges for serum GST B1 were established in a paediatric control population.

Familial hypercholesterolaemia: pilot study to identify children at risk.

Aims: To evaluate a more effective method of identifying children with familial hypercholesterolaemia by screening a population at high risk.

Methods: Domiciliary measurement of random cholesterol concentration was made in 200 children who were first or second degree relatives of subjects with premature onset coronary artery disease. Measurements were taken by a health visitor using a portable analyser.

Homozygous acute intermittent porphyria: compound heterozygosity for adjacent base transitions in the same codon of the porphobilinogen deaminase gene.

A sister and brother with severe porphobilinogen (PBG) deaminase deficiency are described. Each of their parents carries a different mutation for acute intermittent porphyria and the children are homozygous for the PBG-deaminase deficiency that causes this disorder. Both are compound heterozygotes for adjacent base transitions in the same codon in exon 10 of the PBG deaminase gene.

The ratio of plasma phenylalanine to other large neutral amino acids is not a risk factor for tardive dyskinesia.

The ratio of the plasma concentration of phenylalanine (PA) to the sum of the plasma concentrations of other large neutral amino acids (LNAA) was calculated in 26 chronic, in-patient schizophrenics who met diagnostic criteria for tardive dyskinesia and 22 patients who did not. No difference in the PA/LNAA ratio was found between the two groups. Small positive correlations were found between age and both PA/LNAA ratio and tardive dyskinesia.

D(+)-glyceric aciduria: etiology and clinical consequences.

A family comprising mother, father, and five children is described. Four of the children were found to excrete massive amounts of D(+)-glyceric acid in their urine. This was verified by gas chromatography-mass spectrometry and the configuration determined by capillary gas chromatography of O-acetylated menthyl esters.

Isolated fructose malabsorption.

A patient with isolated fructose malabsorption presented with diarrhoea and colic during the first year of life and subsequently responded to a fructose free diet. Fructose malabsorption has been implicated in some cases of irritable bowel syndrome in adults and may also be an infrequently recognised cause of gastrointestinal symptoms in children.

Establishment of an external quality-assessment scheme for amino acid analyses: results from assays of samples distributed during two years.

Ten different samples of lyophilized plasma and two of liquid urine were distributed during two years to 26 laboratories performing quantitative amino acid analyses in a scheme designed to provide external quality assessment. After each distribution, statistical summaries and performance scores based on delta standard deviations and percentage biases from the all-laboratory trimmed means were returned to participants, who also received annual performance summaries based on their accumulated results. Coefficients of variation calculated from returns across all the samples ranged from 13% for glycine to 65% for methionine.

Dried blood spot glucose measurement in hyperinsulinaemic hypoglycaemia.

A retrospective analysis of dried blood spot glucose profiles found them to provide useful information about the progress of a child with hyperinsulinism due to nesidiodysplasia. The potential for their use in the management of such cases is discussed.

Urinary excretion of 3-methylhistidine, creatinine and total nitrogen by Kenyan children during acute measles and after recovery.

The urinary excretion of 3-methylhistidine (3MH), creatinine and total nitrogen was measured during the course of energy balance studies on 20 black Kenyan children. Studies were carried out over 24 h during an acute attack of measles with a second (control) study after recovery, and complete urinary collections were obtained on 14 ill and 18 recovered children. The nutritional status was assessed by anthropometry, and energy intake was determined by duplicate diet analysis.

Identification of the cause of separation (creaming) of lipid emulsions in intravenous infusion.

Over a 2-month period, white deposits were found in infusion sets delivering parenteral nutrition mixtures that included a lipid emulsion. When components of the infusion were mixed in the laboratory, separation (creaming) of the emulsion could be demonstrated, and this enabled us to predict the concentrations of the prescribed infusates that were likely to cream. Further investigations showed that creaming occurred when the lipid emulsion was mixed with heparin and calcium ions at concentrations above 1 U/ml and 1 mumol/ml, respectively.

Acceptance of domiciliary theophylline monitoring using dried blood spots.

Filter paper cards incorporating dried blood spots for the measurement of theophylline concentrations were returned by 62 out of 100 asthmatic children sent kits with instructions for their collection. Analysis of the blood spots showed that 37 (61%) of the children who returned them had less than therapeutic blood theophylline concentrations, in 21 (34%) they were therapeutic, and in three (5%) they were potentially toxic. The results indicate that most asthmatic children would comply with requests for home monitoring of theophylline concentrations, and that only one third of children receiving theophylline achieved blood concentrations and that only one third of children receiving theophylline achieved blood concentrations within the therapeutic range.

Transient neonatal galactosaemia.

A 4 week old infant who failed to thrive was found to have galactose in his urine. Plasma galactose concentration was grossly raised (4.48 mmol/l; reference range less than 0.

Measurement of theophylline in dried blood spots by spectrophotometric enzyme immunoassay.

A widely-used enzyme immunoassay for the measurement of theophylline in plasma (EMIT) has been adapted for use with dried blood spots. Potential interference from haemoglobin in eluates of the spots was avoided by autoclaving them prior to analysis. The method was investigated in terms of the recovery of theophylline added to samples, precision, and the correlation of results in DBS with those in plasma samples.

Screening tests for glycosaminoglycans in urine: experience from regional interlaboratory surveys.

Three urine samples were distributed to laboratories in the Trent and Yorkshire regions to assess their ability to detect glycosaminoglycans. Satisfactory results were obtained for samples from patients with Hunter's and Morquio's diseases but six of 14 laboratories reporting a result for a Sanfilippo sample missed the abnormality. Replies to a subsequent questionnaire showed that unsuccessful laboratories were not using recommended screening methods, that they lacked experience in testing for these diseases, and that rationalisation of such screening services may be indicated.

Clodronate in the medical management of hyperparathyroidism.

The skeletal manifestations of hyperparathyroidism are due to the stimulation of osteoclast-mediated bone resorption by high circulating concentrations of parathyroid hormone (PTH). Since diphosphonates inhibit PTH-mediated bone resorption, we assessed the effects of clodronate in 42 patients with hypercalcaemia and increased bone resorption due to primary hyperparathyroidism (20 patients), secondary hyperparathyroidism in chronic renal failure (12 patients on haemodialysis replacement therapy) and tertiary hyperparathyroidism following successful renal transplantation (10 patients). Clodronate (0.