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L X Wang

Publications and source records attributed to L X Wang.

59 records · Page 4Linked to original sources
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The inhibition and protection of cholinesterase by physostigmine and pyridostigmine against Soman poisoning in vivo.

It has been shown that some reversible cholinesterase (ChE) inhibitors as physostigmine and pyridostigmine are prophylactically effective in organophosphate poisoning. The inhibition and protection of ChE against Soman poisoning with the above mentioned drugs was investigated in mice. (1) Physostigmine and pyridostigmine significantly inhibited the ChE in whole blood in vivo and their inhibitory potencies with equitoxic doses were approximately equal (1/5LD50 about 30%; 1/2 LD50 about 45% respectively). Physostigmine also significantly inhibited brain ChE and its potency was slightly weaker than that in blood; but pyridostigmine only slightly inhibited brain ChE (17%) with large dose (1/2 LD50). The extent of inhibition was in parallel with the dosage of the drugs used. (2) Physostigmine had definite protection in the blood and brain ChE against Soman poisoning. The extent of protection was in parallel with the dosage used. The protection of blood ChE by pyridostigmine was weaker than that by physostigmine. There was no protection of brain ChE by pyridostigmine. (3) The inhibitory potency of equitoxic doses of physostigmine and pyridostigmine in the ChE of diaphragm muscle was equal too (1/2 LD50 about 45%), and the protective effect of physostigmine was still greater than that of pyridostigmine in Soman poisoning. (4) The time course of blood ChE inhibition by physostigmine in vivo was of short duration. While 30 minutes after administration of physostigmine, the ChE activity gradually recovered and it returned to normal level after 4 hours. The blood ChE inhibition by pyridostigmine reached a peak level after 2 hours, and the ChE activity slowly increased after 4 hours, but there was 30% of ChE activity still inhibited after 8 hours. Physostigmine and pyridostigmine, the reversible ChE inhibitors with carbamate structure, have definite ChE protection against Soman poisoning. The prophylactic efficacy was obviously correlated with their ChE protective potency. Evaluating physostigmine and pyridostigmine based on their efficacy, toxicity, adverse effects, duration, availability and stability, we recommend that pyridostigmine is the drug of choice in the prophylaxis against nerve gas poisoning.

Animals↗
PubMedDate not supplied

Role of left cardiac sympathetic denervation in the management of congenital long QT syndrome.

Congenital long QT syndrome (LQTS) is a rare but life-threatening disorder affecting cardiac electrophysiology. It occurs due to mutation in genes encoding for the ion channels in ventricular cell membrane. Syncopal attacks and cardiac arrest are the main symptoms of the disease. Anti-adrenergic therapy with oral beta-blockers has been the mainstay of treatment for LQTS. However, up to 30% of patients fail to respond to medical therapy and remain symptomatic. An alarming 10% of patients still experience cardiac arrest or sudden cardiac death during the course of therapy. Left cardiac sympathetic denervation (LCSD) has been used as an alternative therapy in patients who are resistant to beta-blockers. Although LCSD appears effective in reducing the frequency of syncopal attacks and improving the survival rate in both the short and long-term, its use has not gained popularity. The recent advent of minimally invasive thoracoscopic sympathectomy may improve the acceptance of LCSD by physicians and patients in the future. The primary objective of this article was to review the current evidence of the clinical efficacy and safety of LCSD in the management of LQTS. The review was based on Medline search of articles published between 1966 and 2002.

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