Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The major use of N-acetylcysteine in clinical toxicology is in the treatment of acetaminophen (paracetamol) overdosage. The hepatorenal toxicity of acetaminophen is mediated by a reactive metabolite normally detoxified by reduced glutathione. If glutathione is depleted, covalent binding to macromolecules and/or oxidation of thiol enzymes can lead to cell death. Oral or intravenous N-acetylcysteine or oral D,L-methionine mitigates acetaminophen-induced hepatorenal damage if given within 10 hours, but becomes less effective thereafter. In vivo, N-acetylcysteine forms L-cysteine, cystine, L-methionine, glutathione, and mixed disulfides; L-methionine also forms cysteine, thus giving rise to glutathione and other products. Oral therapy with N-acetylcysteine or methionine for acetaminophen poisoning is contraindicated in the presence of coma or vomiting, or if activated charcoal has been given by mouth. Nausea, vomiting, and diarrhea may also occur as a result of oral N-acetylcysteine administration. Anaphylactoid reactions including angioedema, bronchospasm, flushing, hypotension, nausea/vomiting, rash, tachycardia, and respiratory distress may occur 15-60 minutes into N-acetylcysteine infusion (20 hours intravenous regimen) in up to 10% of patients. Following accidental intravenous overdosage, the adverse reactions of N-acetylcysteine are similar but more severe; fatalities have occurred. A reduction in the loading dose of N-acetylcysteine may reduce the risk of adverse reactions while maintaining efficacy. Administration of N-acetylcysteine for a longer period might provide enhanced protection for patients in whom acetaminophen absorption or elimination is delayed. N-acetylcysteine may also have a role in the treatment of toxicity from carbon tetrachloride, chloroform, 1,2-dichloropropane, and other compounds. The possible use of N-acetylcysteine and other agents in the prevention of the neuropsychiatric sequelae of acute carbon monoxide poisoning is an important area for future research.
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PMID:Use of N-acetylcysteine in clinical toxicology. 192 4

Reaction of sulfhydryl-containing compounds, RSH, with Ce4+ in the presence of the spin trap phenyl-N-t-butylnitrone results in the appearance of a nitroxide ESR spectrum, which is greatly diminished if the sulfhydryl group is blocked prior to reaction. The spectra have short lifetimes which can be increased two- to fivefold to half-lives of 5-60 min by prior flushing of the solutions with nitrogen. For small molecules, such as cysteine, N-acetylcysteine, glutathione, and 2-mercaptoethanol, the spectrum is that of a freely rotating nitroxide while for the proteins, bovine serum albumin and myosin, the spectrum is characteristic of a strongly immobilized nitroxide spin label rigidly attached to the protein. Since Ce4+ is reported to oxidize the sulfhydryl group via the thiyl radical, RS, the following reactions are proposed to account for the formation of the nitroxide: (formula; see text) These reactions permit the spin labeling of sulfhydryl proteins such that the nitroxide is much closer to the point of attachment than when using conventional spin-labeling methods.
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PMID:Spin labeling of protein sulfhydryl groups by spin trapping a sulfur radical: application to bovine serum albumin and myosin. 631 94

Treatment of paracetamol intoxication with N-acetylcysteine (NAC) is standard in Denmark. NAC is considered safe with relatively few side effects. It is recommended that all patients be treated irrespective of paracetamol dose or time from intoxication to treatment start. Consequently a higher number of patients will be treated with NAC than with previous regimens based on plasma concentrations of paracetamol. In this retrospective study we evaluated the incidence of side effects of NAC in 310 patients admitted to the Department of Hepatology, Rigshospitalet, Copenhagen, over a four-year period (1.1.1994-31.12.1997). Twenty-six (8.4%) patients developed side effects. Side effects were anaphylactoid, mainly from skin (25 rash, pruritus or flushing), in rare cases more serious (four bronchospasm, three angioedema, one hypotension). None were life-threatening and all patients received the full course of NAC. In all cases the recommended treatment with antihistamine or steroids against adverse effects was administered. We conclude that treatment with NAC is safe. Accordingly we find no reason to change the recommendation for treatment of paracetamol intoxication in Denmark.
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PMID:[Side-effects of N-acetylcysteine treatment in patients with paracetamol poisoning]. 1048 14

We studied the effects of advanced glycation end products (AGEs), which are known to accumulate in patients with diabetes, autoimmune diseases, or those who smoke, on embryonal development. Pronuclear (PN) embryos were obtained by flushing the fallopian tubes of rats after superovulation and mating. The cleavage rate and blastocyst yield were evaluated at 24, 72, 96, and 120 h of culture. Glyoxal, an AGE-forming aldehyde, suppressed embryonal development at every stage from PN to blastocyst in a concentration-dependent manner. The cleavage rate of the embryo was also signifi cantly decreased by treatment with glyoxal at concentrations of 1 mM or higher. The blastocyst yield was significantly decreased by treatment with glyoxal at concentrations of 0.5 mM or higher. N-acetyl-L-cysteine (L-NAC) at 1 mM significantly suppressed the glyoxal-induced embryonal toxicity. BSA-AGEs at 5 microg/ml or higher concentration signifi cantly reduced the cleavage rate and blastocyst yield compared to those for BSA-treated embryos. L-NAC at 1 mM significantly suppressed BSAAGE-induced embryonal toxicity. Because AGEs are embryo-toxic, AGE contamination may influence the pregnancy rate of in vitro fertilization and embryo transfer. AGEs, which are increased in women under pathological conditions, may also be involved in their infertility.
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PMID:Adverse effects of advanced glycation end products on embryonal development. 1846 85

N-Acetylcysteine is useful in the short-term treatment of severe Raynaud's phenomenon and digital ulcers (DU) in patients with systemic sclerosis (SSc), but its long-term effects are largely unknown. The aim of this study was to report long-term outcome (median follow-up 3 years) in a prospective study of a cohort of 50 consecutive patients with SSc who received N-acetylcysteine (NAC) infusional therapy every 2 weeks. We observed a reduction of DU/patient/year (4.5 +/- 3.1 vs 0.81 +/- 0.79) and DU ulcer visual analog scale (VAS; 6.88 +/- 2.62 vs 3.20 +/- 1.80), a decrease of the Raynaud's phenomenon (RP) number attacks (7.18 +/- 3.87 vs 3 +/- 1.92), and RP VAS (6.24 +/- 1.92 vs 3.62 +/- 1.48). In this study, we did not observe serious adverse events in patients. Minor side effects were flushing (two patients) and headache (one patient). NAC infusion was generally well tolerated, and nobody had to discontinue the treatment. In conclusion, long-term therapy with NAC, in patients with SSc, has a durable effectiveness on ischemic ulcers and Raynaud's phenomenon.
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PMID:The treatment with N-acetylcysteine of Raynaud's phenomenon and ischemic ulcers therapy in sclerodermic patients: a prospective observational study of 50 patients. 1969 Sep 39

Intravenous N-acetylcysteine is usually regarded as a safe antidote. However, during the infusion of the loading dose, different types of adverse drug reactions (ADR) may occur. The objective of this study was to investigate the relation between the incidence of different types of ADR and serum acetaminophen concentration in patients presenting to the hospital with acetaminophen overdose. This is a retrospective study of patients admitted to the hospital for acute acetaminophen overdose over a period of 5 years (1 January 2004 to 31 December 2008). Parametric and non-parametric tests were used to test differences between groups depending on the normality of the data. SPSS 15 was used for data analysis. Of 305 patients with acetaminophen overdose, 146 (47.9%) were treated with intravenous N-acetylcysteine and 139 (45.6%) were included in this study. Different types of ADR were observed in 94 (67.6%) patients. Low serum acetaminophen concentrations were significantly associated with cutaneous anaphylactoid reactions but not other types of ADR. Low serum acetaminophen concentration was significantly associated with flushing (p < 0.001), rash (p < 0.001) and pruritus (p < 0.001). However, there were no significant differences in serum acetaminophen concentrations between patients with and without the following ADR: gastrointestinal reactions (p = 0.77), respiratory reactions (p = 0.96), central nervous reactions (p = 0.82) and cardiovascular reactions (p = 0.37). In conclusion, low serum acetaminophen concentrations were associated with higher cutaneous anaphylactoid reactions. Such high serum acetaminophen concentrations may be protective against N-acetylcysteine-induced cutaneous ADR.
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PMID:Relationship between serum acetaminophen concentration and N-acetylcysteine-induced adverse drug reactions. 2037 38