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Biomedical subjects

E J Thompson

Publications and source records attributed to E J Thompson.

At least 181 records · Page 10Linked to original sources
PubMed1982

On the relationship of CSF pleocytosis to immunoglobulin levels as estimated by different techniques.

One might expect a positive correlation between the number of CSF lymphocytes and the relative amount of CSF IgG, especially in cases of local synthesis of IgG within the CNS. However, previous attempts at correlating the number of CSF lymphocytes with IgG levels have yielded varying results. Since it is known that the estimation of CSF IgG levels can vary according to the method of immunoglobulin determination used, we decided to perform the analyses by three separate methods: (1) the commonly used, immunoprecipitation technique of radial immunodiffusion; (2) physico-chemical separation on the basis of hydrated size/charge using alkaline electrophoresis through the molecular sieving effects of polyacrylamide gels, followed by densitometry of the gamma region of Coomassie Blue-stained proteins; (3) separation into constituent Ig heavy chains and light chains on the basis of unfolded chain lengths by molecular sieving using sodium dodecyl sulphate (SDS), followed by densitometry of heavy chains of immunoglobulins having been labelled with the fluorescent dye dansyl chloride. Our results show a correlation of white count with the latter two techniques but not the former. Possible reasons for discrepancies in the literature are discussed with regard to the peculiar physical properties of the selected CSF IgG molecules.

Cerebrospinal Fluid↗
PubMed1982

Measurement of body fluid proteins by polyacrylamide gel electrophoresis.

A development of the disc polyacrylamide gel electrophoretic system of Ornstein and Davis, which has been applied to the analysis of unconcentrated cerebrospinal fluid, is described. Modifications to the scanning densitometer have improved the signal:noise ratio of the gel scanning system. Using this technique, we have studied the dye-binding properties of albumin, and of beta- and gamma-globulins, and have shown that reproducible quantification of proteins can be achieved. The advantages of electrophoretic methods over immunochemical methods of quantification are discussed.

Cerebrospinal Fluid Proteins↗
PubMed1982

Electrophoretic separation and identification of perilymph proteins in cases of acoustic neuroma.

Previous studies of perilymph proteins have emphasised the difficulty of obtaining samples free of blood or serum proteins. The present investigation has established a method of polyacrylamide gel electrophoresis, which enables contaminated specimens to be readily identified and therefore discarded. Analysis of uncontaminated samples has confirmed the presence of an elevated perilymph protein in cases of acoustic neurinomata. Perilymph proteins have been separated and identified and although no characteristic pattern of proteins associated with acoustic neurinomata has emerged, further work should be undertaken to establish the site of origin of perilymph proteins and the pattern of abnormalities to be expected in pathological processes.

Electrophoresis, Polyacrylamide Gel↗
PubMed1982

Electrophoresis of CSF proteins.

In this review we have tried to indicate the potential importance and interest of the proteins of the CSF and have argued that only by electrophoresis can these be examined in context. Without the need for expensive or elaborate equipment, a small volume of CSF can be used to demonstrate the pattern of proteins present, various qualitative changes, and the amounts of some individual proteins. For routine work this is of practical help in the diagnosis of certain neurological conditions, and as a research tool it can be utilized to investigate changes in protein structure and function occurring as part of immune or other responses. Access to neural tissue is necessarily restricted, but there is a great deal to be learned from the CSF.

Blood-Brain Barrier↗
PubMed1981

The Hurler syndrome: detection of patients and heterozygotes using a microassay for alpha-L-iduronidase in fibroblasts.

The activities of alpha-L-iduronidase (EC 3.2.1.76) were measured, by a microassay with phenyl-alpha-L-iduronide as the substrate, in cultured fibroblasts from patients with the Hurler syndrome (MPS IH) or the Scheie syndrome (MPS IS) and from heterozygotes.l The iduronidase activities in the cells from 44 MPS IH and 7 MPS IS patients were all strongly reduced and distinct from the activities in heterozygotes and normal controls. In a group of 24 obligate heterozygotes for MPS IH, 23 could be classified as heterozygotes when the average iduronidase activities of two independent assays were considered. The use of a standard enzyme preparation as a reference in the assays further improved the identification of heterozygosity. The testing of possible heterozygotes (relatives of patients) and their partners may be a valuable contribution in genetic counselling.

Fibroblasts↗
PubMed1981

Creatine kinase isoenzymes in cultured human muscle cells. I. Comparison of Duchenne muscular dystrophy with other myopathic and neurogenic disease.

The amounts of creatine kinase (CK) and the proportions of isoenzymes have been investigated in human primary cultures. There were increases in total CK activity and the transitions in the isoenzyme profiles showed initial patterns in which only the brain form is present, and later in culture showed patterns in which the muscle or hybrid forms are also present. These changes are similar to those found in muscle cultures grown from other species. These parameters have been compared in cultures derived from boys with Duchenne muscular dystrophy and from patients with various neurological diseases. The dystrophic CK activities were significantly lower and the amounts of brain-type isoenzyme were significantly higher than in the cultures from patients with neurogenic disorders, but the values were similar to the cultures from the myopathic group of diseases. The dystrophic CK isoenzyme profiles resembled those produced by cultures examined at time points, early in their growth period when they were less differentiated.

Cells, Cultured↗
PubMed1981

Creatine kinase isoenzymes in cultured human muscle cells. II. A study of carrier females for Duchenne muscular dystrophy by needle and open biopsy.

Creatine kinase (CK) isoenzymes, total and specific CK activities and protein concentrations were measured in the cultured cells from muscle biopsies of 18 carriers of Duchenne muscular dystrophy (DMD) and the results compared with those in the cultures of patients with DMD and other neuromuscular disorders. The proportion of MB and BB isoenzyme in the carriers was similar to that in boys with DMD and in patients with other myogenic disorders, and significantly different from neurogenic patients. CK isoenzyme analysis appears to be a more sensitive index of in vitro differentiation than estimation of CK activities. Cell differentiation is reduced and the incidence of cell death increased in cultures derived from needle rather than open biopsies.

Biopsy↗
PubMed1981

Growth of adult human cells in culture at clonal densities.

The effect of varying medium concentrations of fetal calf serum (FCS), horse serum (HS) and chicken embryo extract (EE) on the growth capacity of adult human cells cultured at clonal densities was investigated. The best growth was consistently obtained with medium containing 20 parts FCS and 2 parts heat-treated commercial EE. The growth potential of human muscle cells was not related to the age of the patient from which the biopsy was taken, but was dependent on the microenvironment of the culture and the cell density.

Animals↗
PubMed1981

Effect of beta-bungarotoxin on the release of endogenous amino aids from the sensorimotor cortex.

beta-Bungarotoxin, a snake neurotoxin purified from the venom of Bungarus multicinctus, caused a significant increase in the in vivo release of glutamate from the superfused sensorimotor cortex of awake animals. A smaller effect on GABA release was observed, but no change was detected in the release of six other amino acids measured. The effects on glutamate and GABA release were entirely blocked by tetrodotoxin (1 micrometer) and were reversible when the cortical tissue was washed with saline.

Amino Acids↗
PubMed1981

Freeze-dried cadaveric dural grafts can stimulate a damaging immune response in the host.

Clinical experience with freeze-dried cadaveric dura mater has suggested that it is an acceptable dural substitute which does not seem to provoke a significant immune response in the host. A patient is described in whom a cadaveric dural graft provoked an immune reaction leading to meningitis, long after any bacterial contamination or 'chemical' reaction would have declared itself. Removal of the graft resulted in full recovery of the patient in parallel with abatement of the immune response as measured in the cerebrospinal fluid. We discuss the experimental basis for claims that this material is not immunogenic and point out that the mechanism for a damaging immune response does exist.

Adult↗
PubMed1980

The morphology of rat soleus neuromuscular junctions treated in vitro with purified beta-bungarotoxin.

Pairs of isolated rat soleus nerve-muscle preparations were maintained in vitro in oxygenated Ringer solution containing 3 microgram/ml beta-bungarotoxin prepared by the method of MacDermot et al. End-plate potentials and twitch tensions generated in response to continuous stimulation via the nerve at 0.5 Hz were recorded from one muscle, while miniature end-plate potential amplitude and frequencies were monitored in the corresponding unstimulated member of the pair. The results obtained were compared with the fine structure of end-plates from identical preparations sampled after varying periods of intoxication, and from unpoisoned muscles maintained for comparable times in vitro. The electron micrographs obtained were analyzed quantitatively using simple stereological techniques. Our results show that: (1) nerve terminal synaptic vesicle content declines for the first hour of intoxication but returns to near normal levels following conduction block; (2) there is a rapid increase in the 'coated' vesicle population of the nerve terminals, both attached to the plasmalemma and within the terminal cytoplasm, which persists to the end of the experiment; and that (3) there is no significant increase in the incidence of damaged mitochondria within the poisoned nerve terminals. These findings are discussed in relation to previous observations and the putative mechanisms of action of beta-bungarotoxin.

Animals↗
PubMed1980

Double-blind, controlled trial of immunosuppression in treatment of multiple sclerosis.

30 multiple sclerosis patients in a double-blind, controlled trial were given immunosuppressive treatment consisting of antilymphocyte globulin, prednisolone, and azathioprine, or placebo. After 15 months of treatment the immunosuppressed group had a reduction in the number of relapses and some retardation of the clinical course of the disease (p < 0.06). The beneficial effect was seen only in females.

Antilymphocyte Serum↗
PubMed1980

Acetylcholine receptors in cultured human muscle cells.

Primary cultures prepared from human muscle biopsies were examined for the presence and distribution of acetylcholine receptors, as measured by the binding of 125iodine-labelled alpha-bungarotoxin. The toxin bound to the human muscle cultures with a similar time dependence and specificity as found in muscle cultures from other species. The amount of toxin bound was lower than that obtained for neonatal mouse muscle under similar conditions. The distribution of receptors was similar in cultures derived from the muscles of patients with a variety of neuromuscular disorders. The toxin was located along the myotubes in a fairly even distribution; however, variations in labelling along a single myotube were observed, as well as variations between different myotubes in the same culture. Occasionally, the toxin also bound to other cells, which may have been mononucleated. Cultures prepared from patients with Duchenne muscular dystrophy produced multi-layered cell clusters, instead of the usual monolayer of cells. Within these clusters, only the myotubes bound alpha-bungarotoxin.

Bungarotoxins↗