Search PubMed⌕ Search

Biomedical subjects

D Edwards

Publications and source records attributed to D Edwards.

At least 109 records · Page 6Linked to original sources

In vitro modulation of the eosinophil-dependent enhancement of the permeability of the bronchial mucosa.

1. Basolateral to apical albumin flux has been measured in sheets of bovine bronchial and tracheal mucosa mounted in vitro. 2. Addition of guinea-pig peritoneal eosinophils or neutrophils to the basolateral side of such tissues had no significant influence on the transmucosal flux of albumin in either the bronchial or tracheal mucosa. 3. Stimulation of eosinophils or neutrophils by the calcium ionophore A23187, or by their presentation to an opsonized airways mucosa, resulted in a significant increase in the transbronchial flux of albumin. This effect was seen after only 60 min incubation of the leucocytes with the bronchial mucosa, and was no greater when the contact time was extended to 180 min. Incubation of bronchial mucosal tissues with 1 mg ml-1 polyarginine for 3 h produced a significant increase in albumin flux, but was ineffective at 0.5 mg ml-1. 4. In contrast to the bronchial mucosa, the tracheal mucosa appeared resistant to the effects of stimulated eosinophils and neutrophils. 5. The lipoxygenase inhibitor AA-861 failed to influence the ability of eosinophils to augment the transmembrane flux of albumin. However, insertion of a Millipore filter mask between the eosinophils and the bronchial mucosa significantly inhibited the eosinophil-dependent enhancement of mucosal permeability. 6. The broad spectrum antiproteinase alpha 2-macroglobulin achieved almost total ablation of the action of stimulated eosinophils in the bronchial mucosa. These results suggest that proteinases may make a significant contribution to the genesis of epithelial injury, whereas leukotrienes do not.

Animals↗

Concentrations of atracurium and laudanosine in cerebrospinal fluid and plasma in three intensive care patients.

We have measured concentrations of atracurium and laudanosine in cerebrospinal fluid (CSF) and plasma in three intensive care patients receiving atracurium infusions of 22.5-106 h duration to maintain neuromuscular block. Two patients had suffered severe closed head injuries and the third patient had developed respiratory failure following the clipping of two intracranial aneurysms. The total dose of atracurium given was 14.3-136.6 mg kg-1; rate of infusion was 0.6-1.38 mg kg-1 h-1. Plasma concentrations of atracurium and laudanosine were 0.73-3.11 micrograms ml-1 and 0.48-8.65 micrograms ml-1, respectively; CSF concentration of laudanosine was 70-440 ng ml-1. No adverse effects attributable to these concentrations of laudanosine were observed.

Adult↗

Bronchography in the assessment of patients with lung collapse for endoscopic laser therapy.

In an attempt to improve selection of patients and the efficacy of endoscopic laser treatment, a bronchographic technique has been developed for patients with tumours causing complete endobronchial obstruction. This technique has shown patent distal airways in 16 out of 17 patients with a collapsed lung or lobe. These airways were abnormally dilated in each case, suggesting bronchiectasis. In one patient the appearances of bronchiectasis were sufficiently severe to decide against attempting treatment. Treatment was not attempted in another patient as a large cavity was seen within the collapsed lung and this was thought to carry a risk of postoperative infection and haemorrhage. Treatment with a neodymium YAG laser under general anaesthesia successfully recanalised the airway in 12 of the 15 remaining patients and was associated with a substantial reduction in breathlessness. The procedure was abandoned prematurely in one patient because of life threatening haemorrhage. In the remaining two patients in whom treatment was unsuccessful bronchography had suggested very extensive endobronchial obstruction. Spirometry and radionuclide lung scans were performed before and after treatment in eight patients treated successfully and showed significant improvements. Four patients were investigated within two weeks of lung re-expansion by repeat bronchography (three patients) or computed tomography (one patient); in each case the calibre of the airways had returned almost to normal. Thus the radiological demonstration of bronchial dilation in a collapsed lung does not necessarily imply a diagnosis of irreversible bronchiectasis and should not be regarded as a contraindication to treatment. It is concluded that preoperative bronchography provides reliable data on the extent of tumour, the patency of the distal airways, and presence of extensive cavitation. This information should facilitate successful laser treatment.

Adult↗

Antibiotic SB22484: a novel complex of the aurodox group. II. Structure elucidation of the four factors.

SB22484, active against Neisseriae gonorrhoeae and Neisseriae meningitidis, is a complex of four factors, designed 1 through 4, which from two pairs of isomers, 1 and 3, and 2 and 4. Factors 1 and 3 account for 65% of the complex, factor 3 being the predominant one. On the basis of the existing and implemented correlations between structure and physico-chemical characteristics (UV and IR spectroscopies, ionization properties, MS as FAB and as negative and positive CI, 1H NMR spectroscopy as 2D COSY and NOESY) in the aurodox field, the complete structures were assigned. Factor 3 can be described as N-[7-[5(R)-[7-[1,2-dihydro-4-hydroxy-1H-2-oxo-3-pyridinyl]-6-methyl- 7-oxo-1(E),3(E),5(E)-heptatrienyl]tetrahydro-3(S),4(R)-dihydrox yfuran-2 (S)-yl]-6(S)-methoxy-5,7(R)-dimethyl-2(E),4(E)-heptadienyl]-alpha (S)-methyl-5(S)-methyltetrahydro-2(S),4(S or R)-dihydroxy-6(S)-[1(E), 3(Z)-pentadienyl]-2H-pyran-2-acetamide. Factor 1 is an epimer of factor 3 with the opposite configuration at the anomeric center. Factors 2 and 4 have an ethyl group instead of the methyl group alpha to the acetamide moiety and are in the same stereochemical relationship as the pair 1 and 3.

Acid-Base Equilibrium↗

Method for evaluating performance of clinical pharmacists.

A performance-evaluation process that satisfies Joint Commission on Accreditation of Healthcare Organizations criteria and state policies is described. A three-part, criteria-based, weighted performance-evaluation tool specific for clinical pharmacists was designed for use in two institutions affiliated with the University of Washington. The three parts are self-appraisal and goal setting, peer evaluation, and supervisory evaluation. Objective criteria within each section were weighted to reflect the relative importance of that characteristic to the job that the clinical pharmacist performs. The performance score for each criterion is multiplied by the weighted value to produce an outcome score. The peer evaluation and self-appraisal/goal-setting parts of the evaluation are completed before the formal performance-evaluation interview. The supervisory evaluation is completed during the interview. For this evaluation, supervisors use both the standard university employee performance evaluation form and a set of specific criteria applicable to the clinical pharmacists in these institutions. The first performance evaluations done under this new system were conducted in May 1989. Pharmacists believed that the new system was more objective and allowed more interchange between the manager and the pharmacist. The peer-evaluation part of the system was seen as extremely constructive. This three-part, criteria-based system for evaluation of the job performance of clinical pharmacists could easily be adopted by other pharmacy departments.

Employee Performance Appraisal↗

Liquid chromatography-mass spectrometry coupling and its application in pharmaceutical research.

The advantages and technical problems related to the on-line connection of liquid chromatography and mass spectrometry are described, with special emphasis on applications in pharmaceutical chemistry. The most important characteristics of various interfaces, such as direct liquid introduction, Magic, continuous flow fast atom bombardment and thermospray, are discussed. Special applications to the study of thermally very labile compounds are considered.

Chromatography, Liquid↗

Concentrations of atracurium and laudanosine in cerebrospinal fluid and plasma during intracranial surgery.

Concentrations of atracurium and laudanosine in cerebrospinal fluid (CSF) and plasma were assayed in nine patients receiving atracurium infusions of 111-251 min duration to maintain neuromuscular block during intracranial surgery. The total dose of atracurium was 1.57-2.60 mg kg-1 and the plasma concentration of atracurium was 1.27-5.44 micrograms ml-1. Concentrations of laudanosine in CSF and plasma increased during the infusion period, and after 125-140 min reached means of 202.5 ng ml-1 and 1448.7 ng ml-1, respectively. The highest recorded concentration of laudanosine in CSF was 570 ng ml-1, in one of two CSF samples found to contain atracurium. After operation, two patients had fits, but these were not thought to be related to laudanosine. It is concluded that during infusion of atracurium, laudanosine accumulates in both plasma and CSF.

Adult↗

Atracurium overdose in a small infant.

An error in setting a syringe driver caused a 2.75 kg infant to receive 37 mg atracurium over 75 minutes. Clinically full recovery of muscle power had returned spontaneously 135 minutes after the infusion was stopped. The child suffered no ill effects. Assay of blood and urine for atracurium and laudanosine confirmed rapid clearance of the drug.

Atracurium↗

Mechanism of hypoxic injury to pulmonary artery endothelial cell plasma membranes.

We exposed monolayer cultures of pulmonary artery endothelial cells or plasma membranes derived from these cells to hypoxic (0 and 5% O2) and normoxic (20% O2; control) conditions and measured cellular contents of malondialdehyde and conjugated dienes, plasma membrane fluidity and lipid composition, and plasma membrane-dependent transport of 5-hydroxytryptamine (5-HT). Hypoxia caused significant increases in malondialdehyde and conjugated dienes, in fluidity, and in 5-HT transport. Hypoxia also caused a significant decrease in plasma membrane total phospholipids and a marked increase in plasma membrane free fatty acids that appeared to be due to release of fatty acids from the plasma membrane phospholipids. The increases in fluidity and 5-HT transport and the alterations in fatty acids were reversible after return to control conditions. These results indicate that hypoxia alters the physical state, lipid composition, and function of endothelial cell plasma membranes by a combination of stimulation of membrane lipid peroxidation and accelerated degradation of membrane phospholipids, the latter probably secondary to activation of membrane phospholipases.

Aerobiosis↗

An air photo analysis of an airplane crash.

Crash patterns-such as cut and damaged vegetation, gouges, debris scatter, burn areas, etc.,-and their spatial relations can be very effectively evaluated by the analysis of stereo aerial photographs. Results from the Canadian Aviation Safety Board's use of aerial photography in the Gander, Nfld., crash of Dec. 12, 1985, show that the technique can lend direct support to an investigation in several ways. It provides an overall perspective view of the regional relations of the crash patterns. It helps direct ground activities. In three-covered areas, it can help establish aircraft attitude and orientation. When combined with debris plots and attitude determinations, it can help establish the breakup sequence. And, when coupled to photogrammetric procedures, it can assign dimensional values to attitude, descent path, areas, lengths, etc.

Accidents, Aviation↗

Ergometrine--a partial agonist at 5-HT receptors in the uterus isolated from the oestrogen-primed rat.

The mechanism of action of ergometrine has been studied in isolated uterus from the oestrogen-primed non-pregnant rat. Ergometrine (30 nM-1 microM) induced spasm and was antagonised selectively by methysergide and ICI 169,369, a proposed competitive antagonist at 5-hydroxytryptamine (5-HT2) receptors. The pA2 values of ICI 169,369 against 5-HT and ergometrine were not significantly different. Ergometrine (0.1-10 microM) was also a selective antagonist of 5-HT with no effect against acetylcholine or potassium chloride. It is suggested that ergometrine is a partial agonist involving 5-HT receptors in rat uterus.

Animals↗

Chlamydia screening.

Explore the source record for details and available documents.

Chlamydia Infections↗