We read with great interest the study in CHEST by Dr. Yasuda and colleagues (June 2004)1 elucidating the role of arteriovenous carboxyhemoglobin (a-vHb-CO) difference in patients with fevers of unknown origin. The authors reported that the presence of an a-vHb-CO difference may be a useful indicator to differentiate between pulmonary and extrapulmonary diseases. This hypothesis was generated fr...

Carbon monoxide (CO) poisoning causes brain damage, which is attenuated by treatment with hydrogen [1], [2], a scavenger selective to hydroxyl radical (•OH) [3]. This suggests a role of •OH in brain damage due to CO poisoning. Studies have shown strong enhancement of •OH production in rat striatum by severe CO poisoning with a blood carboxyhemoglobin (COHb) level > 70% due to 3000 ppm CO, but n...

Carbon monoxide (CO), a highly toxic gas produced by incomplete combustion of hydrocarbons, is a relatively common cause of human injury. Human toxicity is often overlooked because CO is tasteless and odorless and its clinical symptoms and signs are non specific. The brain and the heart may be severely affected after CO exposure with carboxyhemoglobin (COHb) levels exceeding 20%. Damage occurs ...

The aim of the present study was to investigate the effect of endogenous carbon monoxide (CO) on the hydrogen sulfide/cystathionine-γ-lyase (H2S/CSE) pathway in cirrhotic rat livers. The rats were allocated at random into four groups: Sham, cirrhosis, cobalt protoporphyrin (CoPP) and zinc protoporphyrin IX (ZnPP). The expression of hepatic CSE mRNA was evaluated using a quantitative polymerase ...

BACKGROUND Carbon monoxide (CO) is one of the primary components of emissions from light-duty vehicles, and reportedly comprises 77% of all pollutants emitted in terms of concentration. Exposure to CO aggravates cardiovascular disease and causes other health disorders. The study was aimed to assess the negative effects by injecting different amounts of CO concentration directly to human volunte...

We would like to alert toxicologists to the importance of testing for gasoline, and for volatile hydrocarbons in general, in deaths involving inhalation of exhaust fumes occurring in closed spaces with running motors or machinery. We present here a case of suicidal inhalation of motorbike exhaust, a mixture of carbon monoxide (CO) and gasoline vapor, by a 38-year-old female. She was found in he...

We investigated the suitability of a lyophilized bovine hemoglobin (LBH) preparation containing various fractions of oxyhemoglobin (O2Hb), carboxyhemoglobin (COHb), and methemoglobin (MetHb) for quality assessment in multicomponent analysis (MCA) of hemoglobin derivatives. It was demonstrated that a stable preparation of these components after reconstitution yields a hemoglobin solution that is...

Heme oxygenase (HO)-1 is an oxygen-dependent enzyme that may regulate vascular tone and cell proliferation through the production of carbon monoxide (CO). We tested the hypothesis that HO-1 is upregulated in the lung in chronic hypoxia by exposing male Sprague-Dawley rats to 17,000 feet (395 Torr) for 0, 1, 3, 7, 14, or 21 days. After exposure, blood gases, carboxyhemoglobin (COHb) levels, and ...

Carraway, Martha Sue, Andrew J. Ghio, Jacqueline D. Carter, and Claude A. Piantadosi. Expression of heme oxygenase-1 in the lung in chronic hypoxia. Am. J. Physiol. Lung Cell. Mol. Physiol. 278: L806–L812, 2000.—Heme oxygenase (HO)-1 is an oxygen-dependent enzyme that may regulate vascular tone and cell proliferation through the production of carbon monoxide (CO). We tested the hypothesis that ...

In the early 1970s, it was already evident that nicotine dependence was the major factor underlying the maintenance of smoking (1); it was also clear that smokers unconsciously regulate their nicotine intake by reducing puff rate when smoking a high-nicotine cigarette and by increasing it to compensate for the drop in yield when smoking a low-nicotine cigarette (2-5). Confirmation of this self-...