Keary A. Cope

Obesity and female gender increase breath ethanol concentration: potential implications for the pathogenesis of nonalcoholic steatohepatitis

Obesity and female gender increase breath ethanol concentration: potential implications for the pathogenesis of nonalcoholic steatohepatitis

Breath biomarkers and non-alcoholic fatty liver disease: Preliminary observations

Abstract Breath biomarkers have the potential to offer information that is similar to conventional clinical tests or they are entirely unique. Preliminary data support the use of breath biomarkers in the study of liver disease, in particular non-alcoholic fatty liver disease (NAFLD). It was evaluated whether breath ethanol, ethane, sulfur compounds and acetone would be associated with hepatic histopathology amongst morbidly obese patients presenting for bariatric surgery. Breath samples were collected during a preoperative visit and compared with liver biopsies obtained during the surgery. A Students two-tailed t-test was used to compare differences between the two groups. Linear regression was used to analyse associations between the concentrations of breath molecules and independent predictor variables. It was found that breath ethanol, ethane and acetone can be useful biomarkers in patients with NAFLD. In particular, breath ethanol can be associated with hepatic steatosis, and breath acetone can be associated with non-alcoholic steatohepatitis.

Abnormal exhaled ethane concentrations in scleroderma

Abstract Scleroderma (systemic sclerosis) is a chronic multisystem autoimmune disease in which oxidative stress is suspected to play a role in the pathophysiology. Therefore, it was postulated that patients with scleroderma would have abnormally high breath ethane concentrations, which is a volatile product of free-radical-mediated lipid peroxidation, compared with a group of controls. There was a significant difference (p<0.05) between the mean exhaled ethane concentration of 5.27 pmol ml–1 CO2 (SEM=0.76) in the scleroderma patients (n=36) versus the mean exhaled concentration of 2.72 pmol ml−1 CO2 (SEM=0.71) in a group of healthy controls (n=21). Within the scleroderma group, those subjects taking a calcium channel blocker had lower ethane concentrations compared with patients who were not taking these drugs (p=0.05). There was a significant inverse association between lung diffusion capacity for carbon monoxide (per cent of predicted) and ethane concentration (b=−2.8, p=0.026, CI=−5.2 to −0.35). These data support the presence of increased oxidative stress among patients with scleroderma that is detected by measuring breath ethane concentrations.

ORGANIZATIONAL FEATURES AFFECTING THE USE OF COERCION IN THE ADMINISTRATION OF PSYCHIATRIC CARE

Historically, the use of coercion in psychiatric hospital admissions, and research on such use, have reflected social circumstances that impact on psychiatric care. Currently, the social emphasis on cost-saving in the U.S. and corresponding shifts in the organization, financing, and management of psychiatric and mental health care, have begun to affect research on the use of coercion in psychiatric admissions. Such research has begun to incorporate hospital organizational dynamics which affect the use of coercion in these admissions. The authors propose that this emphasis should be expanded into a comprehensive research agenda that examines the most pertinent organizational features affecting the use of coercion in psychiatric hospital admissions.

Propofol and in vivo oxidative stress: effects of preservative*

Reactive oxygen species are associated with tissue inflammation and injury. Our laboratory has demonstrated that ethane, a stable product of lipid peroxidation, in exhaled breath can be used to measure total body oxidative stress. An ischemia-reperfusion model of lung injury in sheep has been studied in which pulmonary and bronchial lung perfusion could be interrupted and restored. The goal of this study was to investigate whether two commercial formulations of propofol and the individual components of the commercial formulations attenuated the oxidative stress produced in this model. Breath ethane and breath carbon monoxide were measured as biomarkers of oxidative stress that occur at reperfusion of ischemic tissue. Data were analyzed by a standard least-squares-fit model. One of the formulations for propofol, which contained the preservative ethylenediaminetetraacetic acid (EDTA), was found to decrease the overall level of oxidative stress in sheep. Furthermore, while several models of severe lung injury demonstrate additional production of reactive oxygen species, our model of ischemia/reperfusion of lung tissue did not.