Noninvasive Surrogate for Physiologic Dead Space Using the Carbon Dioxide Ventilatory Equivalent: Testing in a Single-Center Cohort, 2017-2023.

Objectives: We sought to evaluate the association between the carbon dioxide ( co2 ) ventilatory equivalent (VEq co2 = minute ventilation/volume of co2 produced per min), a marker of dead space that does not require a blood gas measurement, and mortality risk. We compared the strength of this association to that of physiologic dead space fraction (V D /V t = [Pa co2 -mixed-expired P co2 ]/Pa co2 ) as well as to other commonly used markers of dead space (i.e.

A bias in the "mass-normalized" DTT response - an effect of non-linear concentration-response curves for copper and manganese.

The dithiothreitol (DTT) assay is widely used to measure the oxidative potential of particulate matter. Results are typically presented in mass-normalized units (e.g.

Accelerated wound closure in a diabetic mouse model after exposure to phenanthrenequinone.

Background: Reactive oxygen species (ROS) have been shown to be important in wound healing by promoting angiogenesis (also mentioned by Ushio-Fukai and Nakamura). Likewise ROS have been implicated by toxicological studies as a primary mechanism of air pollution-associated morbidity. We sought to determine how exposure to a reactive diesel exhaust chemical (phenanthrenequinone [PQ]), which promotes formation of ROS and is considered an air pollutant, would affect wound healing.

Method development for the measurement of quinone levels in urine.

A method was developed for the quantification of 1-4 ring quinones in urine samples using liquid-liquid extraction followed by analysis with gas chromatography-mass spectrometry. Detection limits for the ten quinones analyzed are in the range 1-2 nmol dm(-3). The potential use of this approach to monitor urinary quinone levels was then evaluated in urine samples from both Sprague-Dawley rats and human subjects.