Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0034063 (pulmonary edema)
 10,665 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hexafluorocyclobutene (HFCB) and derivatives have been used as fumigants, refrigerants and polymerization monomers. When inhaled they produce a potentially fatal pulmonary oedema similar to that induced by perfluoroisobutene (PFIB), a by-product of Teflon manufacture. This study determined the relationship between the chemical structure, respiratory retention and toxicity of HFCB and five analogues in rats and mice. Retention in the rat was determined using a flow-through system combining nose-only exposure and plethysmography. Structural changes to HFCB modified retention. At concentrations of ca. 1 ppm, where uptake was independent of exposure time, the rate of uptake was increased by halogen substitution in the order 3-Br = 1-Br = 1-Cl > 3-Cl = 1-H > HFCB, and was a function of volatility. At concentrations of 6 or 30 ppm, the percentage retained and rate of uptake decreased with time. The total mass retained (micromol kg(-1)) was not proportional to inhaled concentration and was best described by the calculated partition coefficient (octane-water). No clear relationship between retention and reactivity was apparent. The contribution of volatility, partition coefficient and reactivity to the uptake process depended on inhaled concentration. The toxicity of the fluorocyclobutenes agreed with reactivity relationships based on electrophilicity (lowest unoccupied molecular orbital energy), carbanion stability and leaving-group mobility. Toxicity is based principally on the number of successive alkylations (1, 2 or 3) that can occur with tissue nucleophiles.
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PMID:Structure-pulmonary toxicity/retention relationships of inhaled fluorocyclobutenes. 1021 83

The acute respiratory distress syndrome (ARDS) is a complication of critical illness that is characterized by acute onset, protein rich, pulmonary edema. There is no treatment for ARDS, other than the reduction of additional ventilator induced lung injury. Prediction or earlier recognition of ARDS could result in preventive measurements and might decrease mortality and morbidity. Exhaled breath contains volatile organic compounds (VOCs), a collection of hundreds of small molecules linked to several physiological and pathophysiological processes. Analysis of exhaled breath through gas-chromatography and mass-spectrometry (GC-MS) has resulted in an accurate diagnosis of ARDS in several studies. Most identified markers are linked to lipid peroxidation. Octane is one of the few markers that was validated as a marker of ARDS and is pathophysiologically likely to be increased in ARDS. None of the currently studied breath analysis methods is directly applicable in clinical practice. Two steps have to be taken before any breath test can be allowed into the intensive care unit. External validation in a multi-center study is a prerequisite for any of the candidate breath markers and the breath test should outperform clinical prediction scores. Second, the technology for breath analysis should be adapted so that it is available at a decentralized lab inside the intensive care unit and can be operated by trained nurses, in order to reduce the analysis time. In conclusion, exhaled analysis might be used for the early diagnosis and prediction of ARDS in the near future but several obstacles have to be taken in the coming years. Most of the candidate markers can be linked to lipid peroxidation. Only octane has been validated in a temporal external validation cohort and is, at this moment, the top-ranking breath biomarker for ARDS.
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PMID:Diagnosis of acute respiratory distress syndrome by exhaled breath analysis. 2943 Apr 50