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Elizabeth A Gamble

Publications and source records attributed to Elizabeth A Gamble.

2 recordsLinked to original sources

Safety of bronchoscopy, biopsy, and BAL in research patients with COPD.

BACKGROUND: Bronchoscopy with biopsy and BAL is being performed increasingly in patients with COPD as a research tool. Previous reports have shown these procedures to be safe in asthmatic patients, but there is little safety data specific to COPD. METHODS: We studied 57 patients with COPD (11 women and 46 men; median FEV(1), 1.2 L [range, 0.64 to 2.69 L]; percent predicted FEV(1), 44.5% [range, 25 to 74.8%]). Eleven patients had mild disease, 28 patients had moderate disease, and 18 patients had severe disease according to British Thoracic Society classification. Ninety-eight bronchoscopies were performed according to American Thoracic Society guidelines: 68 procedures with endobronchial biopsy and BAL and 30 procedures with biopsy alone. Controlled oxygen was administered via nasal cannula, and pulse oximetry and vital signs were monitored. RESULTS: Five adverse events occurred. One patient in the moderate-disease group had severe bronchospasm requiring 4 days of inpatient treatment. One patient in the severe-disease group had a pneumothorax requiring 7 days of inpatient treatment. There were three episodes of hemoptysis, two with pleuritic pain (in the BAL group) that settled without intervention. No deaths or prolonged morbidity were observed. We found a 2.0% incidence of adverse events requiring hospital treatment and a 3.1% incidence of minor hemoptysis requiring no intervention. CONCLUSIONS: Bronchoscopy, biopsy, and BAL can be performed safely in patients with COPD, including those with severe disease, provided careful assessment is performed and guidelines are adhered to.

Adult↗

Ionic strength dependence of protein-polyelectrolyte interactions.

The effect of univalent electrolyte concentration on protein-polyelectrolyte complex formation has been measured by frontal analysis continuous capillary electrophoresis (FACCE) and turbidimetry for the interaction of bovine serum albumin (BSA) with a synthetic hydrophobically modified polyacid, for BSA with (porcine mucosal) heparin (Hp), a highly charged polyanion, and for Hp and insulin. All three highly diverse systems display maxima or plateaus in complex formation in the range of ionic strength 5 < I < 30 mM, confirmed in the case of BSA-Hp by multiple techniques. Similar maxima are reported in the literature, but with little discussion, for BSA-poly(dimethyldiallylammonium chloride), lysozyme-hyaluronic acid, and lysozyme-chondroitin sulfate, always in the I range 5-30 mM. While inversion of salt effect has been discussed specifically for the interaction of gelatin and sodium polystyrenesulfonate with gelatin(28) and with beta-lactoglobulin,(10) the general nature of this phenomenon, regardless of polyelectrolyte origin, molecular weight, and charge sign has not been recognized. The position of the maxima and their occurrence when protein and polyelectrolyte have the same net charge imply that they arise when Debye lengths extend, at low I, beyond half the protein diameter so that addition of salt screens repulsions, as well as attractions. This appears to be a general effect caused by electrostatic repulsions that can coexist simultaneously with hydrophobic interactions. Modeling of protein electrostatics via Delphi is used to visualize this effect for BSA, lysozyme, insulin, and beta-lactoglobulin.

Electrolytes↗