The externally derived portion of the hyperosmotic shock-activated cytosolic calcium pulse mediates adaptation to ionic stress in suspension-cultured tobacco cells.

The influx of Ca(2+) into the cytosol has long been suggested to serve as a signaling intermediate in the acquisition of tolerance to hyperosmotic and/or salinity stresses. Here we use aequorin-transformed suspension-cultured tobacco cells to directly assess the role of cytosolic calcium (Ca(2+)(cyt)) signaling in salinity tolerance acquisition. Aequorin luminescence recordings and (45)Ca influx measurements using inhibitors of Ca(2+) influx (Gd(3+) and the Ca(2+)-selective chelator EGTA), and modulators of organellar Ca(2+) release (phospholipase C inhibitors U73122 or neomycin) demonstrate that hyperosmolarity, whether imposed by NaCl or by a non-ionic molecule sorbitol, induces a rapid (returning to baseline levels of Ca(2+) within 10 min) and complex Ca(2+)(cyt) pulse in tobacco cells, deriving both from Gd(3+)-sensitive externally derived Ca(2+) influx and from U73122- and neomycin-sensitive Ca(2+) release from an organelle.

Specificity of the fluorescein transport process in Malpighian tubules of the cricket Acheta domesticus.

We demonstrate the presence of an efficient, multispecific transport system for excretion of organic anions in the Malpighian tubules of the cricket Acheta domesticus using fluorescein (FL) as a model substrate. Malpighian tubules rapidly accumulated FL via a high affinity process (Km = 7.75 micromol l(-1)); uptake was completely eliminated by the prototypical organic anion transport inhibitor probenecid (1 mmol l(-1)), but not by p-aminohippuric acid (3 mmol l(-1)).

Informed nursing practice: the administration of oxygen to patients with COPD.

Although the Hypoxic Drive Theory has been a long-time influence on the care of patients with chronic obstructive pulmonary disease (COPD), in reality a relatively fine line exists between optimal and excessive oxygen therapy. Medical-surgical nurses need a clear understanding of the benefits and the possible complications of oxygen therapy in patients with COPD.

Preoperative anxiety in women.

Preoperative anxiety and fear can have adverse effects on patients' perioperative experiences. This study emerged from a larger study in which the researcher examined the perioperative experiences of women. The purpose of this study was to further investigate and describe the nature of preoperative anxiety in female subjects.

Lived experiences, values, and behavior of effective nurse faculty.

This study explored the lived experiences of effective female nurse faculty. The study was guided by a feminist framework. A field study was the specific qualitative approach employed.