PubMed Health⌕ Search

Biomedical subjects

L Coleman

Publications and source records attributed to L Coleman.

At least 37 records · Page 2Linked to original sources
PubMed1992

Cultivation of Borrelia burgdorferi from erythema migrans lesions and perilesional skin.

Skin biopsy specimens from the peripheral aspect of erythema migrans lesions (site 1) and from clinically normal perilesional areas (site 2) were compared as sources of Borrelia burgdorferi. This spirochete was isolated from the skin of 18 of 21 (86%) patients with untreated early Lyme disease at one or both biopsy sites. Site 1 specimens were superior to site 2 specimens for the isolation of B. burgdorferi. Site 1 specimens from 18 (86%) patients were culture positive, and site 2 specimens from 12 (57%) patients were culture positive. For patients whose site 2 specimens were culture positive, site 1 specimens were also found to be culture positive. B. burgdorferi was isolated from two patients with atypical lesions and from two patients with erythema migrans lesions that were less than 5 cm in diameter. This study demonstrates that the cultivation of B. burgdorferi from skin biopsy specimens from cutaneous lesions thought to be erythema migrans can be an efficacious procedure for confirming the diagnosis of Lyme disease and that the spirochete is present in clinically normal appearing perilesional skin.

Adult↗
PubMed1991

MR of progressive neurodegenerative change in treated Menkes' kinky hair disease.

MR examinations of a male child with Menkes' kinky hair disease, a genetic disorder of copper metabolism, at four months and 30 months, document the progression of neurodegenerative changes despite parenteral copper therapy. These changes include severe cortical and cerebellar atrophy, deranged cerebral vasculature, and subdural fluid collection.

Brain↗
PubMed1991

Chloride channels on epithelial cells cultured from human fetal epididymis.

Using single-channel recording techniques, we have detected two types of outwardly rectifying chloride channel on epithelial cells cultured from human fetal epididymis. A small-conductance channel (2.8-5.0 pS) was spontaneously active in 29% of cell-attached patches but rapidly disappeared on patch excision. This channel often occurred in clusters and exhibited slow kinetics with open and closed times of the order of tens or hundreds of msec; an open-state probability that was essentially independent of voltage; and a very low permeability to bicarbonate relative to chloride. Exposing epididymal cells to either forskolin (3 microM) or adrenaline (1 microM) activated this channel (up to 350-fold), suggesting that it may be involved in cyclic AMP-mediated anion secretion by the male reproductive tract. The large-conductance channel (14 to 29 pS) was never detected in cell-attached patches but could be activated by depolarization (40 mV) in 3% of excised, inside-out patches. Once activated, opening of this 'large' channel was voltage independent, and it had a relatively high permeability to both gluconate (Pgluconate/Pchloride = 0.24) and bicarbonate (Pbicarbonate/Pchloride = 0.4). The proportion of excised patches that contained this channel was increased 2.5-fold by prior stimulation of the epididymal cells; however, because the channel was never observed in cell-attached patches its physiological role must remain uncertain.

Cells, Cultured↗
PubMed1991

Community acquired pneumonia: aetiology and prognostic index evaluation.

A 10 month prospective study of all adults admitted to Waikato Hospital with community acquired pneumonia was performed to assess aetiology, mortality, hospital stay, and the value of a prognostic index based on that obtained from a British Thoracic Society study. The 92 patients in the survey had a mean age of 56 (range 13-97) years. A microbiological diagnosis was established in 72%; Streptococcus pneumoniae (33%), Mycoplasma pneumoniae (18%), and influenza A virus (8%) were the most common microorganisms. Other causative organisms were Legionella pneumophila (4 cases), Staphylococcus aureus (3), Klebsiella pneumoniae (2), Haemophilus influenzae (2), Nocardia brasiliensis (1), and Acinetobacter calcoaceticus (1). Chlamydia sp, influenza B virus and adenovirus were each found in one case; all were cultured on nasopharygeal aspirates. Aspiration was considered to be the underlying cause in five patients, two with epilepsy and one with pseudobulbar palsy. Five of the six deaths that occurred were in patients over 75 years of age and the other was 69. In four of the six the established causative organisms were Chlamydia sp (1), K pneumoniae (1), and S aureus (2). Patients had a 16 fold increased risk of death if they had two or more of the following on admission: a respiratory rate of 30/minute or more, diastolic blood pressure of 60 mm Hg or less, and either confusion or a plasma urea concentration greater than 7.0 mmol/l.

Adolescent↗
PubMed1991

Expression of the cystic fibrosis gene in human development.

The specialised epithelia lining the respiratory tract, pancreatic ducts, male genital ducts and sweat gland ducts are defective in the severe inherited disease, cystic fibrosis (CF). We have looked at the expression of the CF gene in human fetal tissues to throw light on the development of function in specialised ductal epithelia and to determine the age of onset of the CF disease process. The CF gene is already seen to be transcribed in mid-trimester fetal lung, pancreas and male genital ducts. Hence, by this developmental stage, and before they are fully differentiated, these epithelia have the capability to perform important transport functions. Epithelial cell cultures derived from fetal pancreas and male genital ducts maintain expression of the CF gene in vitro and so form good models for analysing CF gene function and differentiation of these specialised epithelia.

Blotting, Northern↗
PubMed1991

Immortalization of male genital duct epithelium: an assay system for the cystic fibrosis gene.

The epithelia lining the vas deferens and epididymis are directly involved in the pathology of the autosomal recessive disease cystic fibrosis (CF). We have established culture systems for these epithelial cells. Long-term cell lines have now been generated from these primary epithelial cells by transformation with a plasmid containing an origin-defective simian virus 40 (SV40). Lines have been established from vas deferens and epididymis and both maintain expression of the CF gene.

Base Sequence↗
PubMed1991

Heart healthy education. Effectiveness of teaching methods in the workplace.

One fourth to one third of employed workers in this country have at least one of three major risk factors for coronary heart disease. This pilot study examined differences between educational methods used in an occupational setting. The specific aims of the quasi-experimental study were: to determine differences between two groups of subjects who received either group support and instruction or only written instruction; and to determine the association between the practice of heart healthy behaviors and decreased blood cholesterol levels. No significant differences were found between the two groups in cholesterol and behavior changes. However, there was a significant difference between pre- and post-instruction for all subjects. The study documented significant changes in cholesterol levels, cholesterol and fat intake, and weight reduction.

Adult↗
PubMed1990

Anion selectivity and block of the small-conductance chloride channel on pancreatic duct cells.

Rat and human pancreatic duct cells have small-conductance Cl- channels in their apical plasma membranes. These channels are regulated by secretin and adenosine 3',5'-cyclic monophosphate and may function in parallel with Cl(-)-HCO3- exchangers to allow HCO3- secretion from the duct cell. Using the patch-clamp technique, we have now determined the anion permeability sequence of the channel as NO3- greater than Br- approximately I- approximately Cl- much greater than HCO3- much greater than gluconate. From this we conclude 1) that anion permeation involves a weak interaction with charged sites inside the channel pore, 2) that because of the low HCO3-/Cl- permeability ratio it is unlikely that significant amounts of HCO3- could be secreted directly via the channel, and 3) that channel permeability may determine the anion selectivity of secretion. We also show that 5-nitro-2-(3-phenylpropylamino)benzoic acid blocks the small-conductance Cl- channel, whereas 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid has no effect.

Animals↗
PubMed1989

Two types of chloride channel on duct cells cultured from human fetal pancreas.

Using the patch-clamp technique, we have identified two types of chloride channel on duct cells cultured from human fetal pancreas. The channel we observed most frequently exhibited slight outward rectification, had a conductance of 4-7 pS in cell-attached patches, and was present on the apical plasma membrane where it usually occurred in clusters. Its open-state probability was not markedly voltage dependent but was increased up to threefold by exposing duct cells to secretin (10 nM), dibutyryl cyclic AMP (1 mM), or forskolin (1 microM). The other type of chloride channel was only rarely observed. Its current-voltage relationship exhibited marked outward rectification, giving chord conductances of 19 pS for inward currents and 53 pS for outward currents. Although this channel could be activated by sustained depolarization of excised patches, once activated the open state probability was not voltage dependent. While the physiological role of these channels is not firmly established, the small-conductance channel might function in parallel with a Cl- -HCO-3 exchanger to provide a mechanism for electrogenic bicarbonate secretion from the duct cell.

1-Methyl-3-isobutylxanthine↗
PubMed1989

Ductal epithelial cells cultured from human foetal epididymis and vas deferens: relevance to sterility in cystic fibrosis.

A tissue culture system for epithelial cells derived from male human foetal genital ducts has been established. The cells show morphological and biochemical characteristics of ductal epithelial cells, and can be passaged and maintained in culture for considerable periods of time. These cells will provide a suitable system for investigating, by electrophysiological, biochemical and molecular biological methods, the cause of sterility in cystic fibrosis.

Cells, Cultured↗
PubMed1988

Cultured epithelial cells derived from human foetal pancreas as a model for the study of cystic fibrosis: further analyses on the origins and nature of the cell types.

The establishment of a tissue-culture system for epithelial cells derived from human foetal pancreas has recently been reported. Further analyses have now been made on these cells in vitro, together with parallel investigation of the distribution of different cell types within the intact foetal pancreas. Results support the view that the cultured cells are ductal in origin and nature. Pancreatic epithelial cell cultures have also been established from foetuses with cystic fibrosis.

Cells, Cultured↗
PubMed1987

Hypercholesterolemia and the baboon cerebral circulation.

We investigated cerebrovascular vasodilator responses to increased arterial CO2 and the cerebrovascular response to infused 5-hydroxytryptamine (5-HT) in normal and hypercholesterolemic baboons. After 6-8 weeks of feeding an atherogenic diet the plasma cholesterol levels were increased without change in the triglycerides. The hypercholesterolemic animals showed a higher basal systemic arterial blood pressure than the normal controls without significant decrease in cerebrovascular prostacyclin production, altered basal cerebral blood flow or altered cerebrovascular response to infused 5-HT. However, the vasodilator response to hypercapnia was significantly decreased from the control value of 2.78 ml/min per mmHg increase in PCO2, to 1.62 ml/min per mmHg. Thus functional impairment of cerebral hemodynamics occurred before atherosclerotic alteration in the cerebral vessels could have been present.

Animals↗
PubMed1987

Establishment of a tissue culture system for epithelial cells derived from human pancreas: a model for the study of cystic fibrosis.

A tissue culture system for epithelial cells derived from human foetal pancreas has been established. The cultured cells show many ultrastructural features of interlobular duct cells. Immunocytochemical and histochemical evidence is presented in support of the view that these cells are ductal in origin. They are likely to be one of the few cell types that express the basic defect of cystic fibrosis in vitro. The cells may be passaged and sufficient material obtained to permit biochemical and molecular biological analysis.

Cells, Cultured↗
PubMed1986

In vivo actions of a calcium channel blocker (nimodipine) on the cerebrovascular response to infused 5-hydroxytryptamine.

Previous in vitro studies show that the calcium channel blocker, nimodipine, inhibits the cerebrovascular contraction elicited by 5-hydroxytryptamine (5-HT). The present study determined if this effect was present in vivo in the baboon cerebral circulation rendered sensitive to infused 5-HT by prior intracisternal injection of autologous blood. Five to seven days after injection of this blood the five baboon displayed a vasoconstrictor response to intracarotid 5-HT at 10 micrograms/kg/min (cerebrovascular resistance increased from 2.19 +/- 0.16 to 2.75 +/- 0.30 mm Hg/ml X min-1). Subsequent i.v. infusion of nimodipine produced cerebral vasodilation with an efficacy similar to that in normal baboons. Reinfusion of 5-HT during nimodipine infusion caused a cerebrovascular resistance increase of similar magnitude to that in the prenimodipine test. These results suggest that nimodipine produces cerebral vasodilation after a mild cerebrovascular insult but did not significantly reduce the vasoconstrictor response to 5-HT.

Animals↗