BACKGROUND It is a common practice to anesthetize patients before performing a thoracentesis. We postulated that this technique may cause a clinically significant difference in the pH of the pleural fluid. METHODS We compared two methods of determining pleural fluid pH. Fifty patients undergoing diagnostic or therapeutic thoracentesis were enrolled. Two 4-mL aliquots of pleural fluid were ana...

BACKGROUND Ventilator management for children with hypoxemic respiratory failure may benefit from ventilator protocols, which rely on blood gases. Accurate noninvasive estimates for pH or P(aCO2) could allow frequent ventilator changes to optimize lung-protective ventilation strategies. If these models are highly accurate, they can facilitate the development of closed-loop ventilator systems. W...

The limitations of fungal laccases at higher pH and salt concentrations have intensified the search for new extremophilic bacterial laccases. We report the cloning, expression, and characterization of the bacterial cotA from Bacillus clausii, a supposed alkalophilic ortholog of cotA from B. subtilis. Both laccases were expressed in E. coli strain BL21(DE3) and characterized fully in parallel fo...

In biocatalytic conversions, substrates and products may display inhibitory or toxic effects on the biocatalyst. Rhodococcus erythropolis 1awq could further remove sulfur from hydrodesulfurized diesel oil, and the biodesulfurization was enhanced by the surfactant Tween 80. Tween 80 was shown to decrease the product concentration associated with the cells, reducing product inhibition.

Steroid hormones alter dendritic architecture in many animals, but the exact relationship between dendritic anatomy, synaptic strength, and behavioral expression is typically unknown. In larvae of the moth Manduca sexta, the tip of each abdominal proleg (locomotory appendage) bears an array of mechanosensory hairs, each innervated by a planta hair sensory neuron (PH-SN). In the CNS, PH-SN axons...

The thermoacidophilic archaeon Sulfolobus solfataricus P2 encodes three hypothetic endo-beta-glucanases, SSO1354, SSO1949 and SSO2534. We cloned and expressed the gene sso1949 encoding the 334 amino acids containing protein SSO1949, which can be classified as a member of glycoside hydrolase family 12. The purified recombinant enzyme hydrolyses carboxymethylcellulose as well as cello-oligomers, ...

The effects of tear-film hypoxia and contact lens wear on human in vivo stromal pH was tested using a non-invasive fluorometric technique. Hypoxia was produced by exposing the normal open eye to 100% nitrogen gas passed through tight-fitting goggles. Stromal pH dropped from 7.53 +/- 0.02 to 7.34 +/- 0.03 (n = 12, +/- SD) within 90 min of nitrogen gas exposure, t1/2 = 20 min. After removing the ...

The structures of micelles of the surfactant polysorbate 80 (Tween 80) in 0-50% aqueous dimethyl sulfoxide (DMSO) solutions (pH 7.2, ionic strength 2.44 mM) were investigated by means of small-angle X-ray scattering. At DMSO concentrations of 0-20%, core-shell cylinder micelles formed, and at 30-50% DMSO, core-shell discus micelles formed, that is, changing the hydrophobicity of the DMSO solven...

The molten globule (MG) state of proteins is widely detected through binding with 1-anilino-8-naphthalene sulphonate (ANS), a fluorescent dye. This strategy is based upon the assumption that when in molten globule state, the exposed hydrophobic clusters of protein are readily bound by the nonpolar anilino-naphthalene moiety of ANS molecules which then produce brilliant fluorescence. In this wor...