Greater nasal nitric oxide output during inhalation: effects on air temperature and water content.

The nose conditions the temperature and humidity of nasal air, and the nasal mucosal vasculature supplies heat and water for these processes. We hypothesize that nitric oxide (NO) modulates these processes through vasoactive effects on nasal mucosal vasculature. We measured the temperature, humidity and NO concentrations of nasal air during inhalation and exhalation across the nose and calculated net heat, water and NO output before (controls, n=7) and after inhibition of NO synthase by topical l-NAME (N=5) in healthy humans.

Direct coextensive plethysmography for non-invasive measurement of systemic pressures and volumes.

A method for noninvasive measurement of pressures and fluid volumes of the complete systemic vascular circuit, called direct coextensive plethysmography, is proposed. This includes the pressures of the large veins, small veins, venules, capillaries, arterioles, small arteries, large arteries and nonvascular fluid compartments. It uses a conventional pressure cuff on the outside of the arm, combined with a tetrapolar bioimpedance electrode band to derive a fluid volume indication (impedance) versus pressure profile for the entire system.

Exhaled nasal nitric oxide output is reduced in humans at night during the sleep period.

The physiologic function of nasal nitric oxide (NO) release is unknown. In prior experiments, topical NG-nitro-L-arginine methyl ester (L-NAME) on nasal mucosa reduced exhaled nasal NO output and caused daytime sleepiness. We hypothesized that nasal NO output is reduced at night during the sleep period.

Effects of Ginkgo biloba on exhaled nasal nitric oxide during normobaric hypoxia in humans.

Ginkgo biloba, an extract of the ginkgo tree, may prevent or lessen symptoms of acute mountain sickness in humans. The mechanism of this effect is poorly understood. One hypothesis is that ginkgo alters nitric oxide (NO) metabolism, possibly by scavenging NO or altering nitric oxide synthase expression and thereby lessening the vasodilatory effects of NO.

Use of a clinical pathway to manage unsuspected radiographic findings.

Study Objectives: To describe our 5-year experience with a clinical pathway used to ensure the timely communication and evaluation of unsuspected radiologic findings (URFs) noted on clinically requested chest imaging.

Design: Prospective data collection on clinical practice.

Setting: Academically affiliated Veterans Affairs medical center.