We present a model for the molecular traffic of ligands, substrates, and products through the active site of cholinesterases (ChEs). First, we describe a common treatment of the diffusion to a buried active site of cationic and neutral species. We then explain the specificity of ChEs for cationic ligands and substrates by introducing two additional components to this common treatment. The first...

BACKGROUND The circulating cholinesterases acetyl- and butyrylcholinesterase may be suppressed and subsequently released from the brain in acute bacterial meningitis. METHODS We report serum activities of acetylcholinesterase and butyrylcholinesterase in paired arterial and jugular venous samples from seven patients with acute bacterial meningitis and eight healthy controls. Paraoxonase 1, wh...

Acetylcholinesterase (AChE) is responsible for the hydrolysis of the neurotransmitter, acetylcholine, in the nervous system. The functional localization and oligomerization of AChE T variant are depending primarily on the association of their anchoring partners, either collagen tail (ColQ) or proline-rich membrane anchor (PRiMA). Complexes with ColQ represent the asymmetric forms (A(12)) in mus...

BACKGROUND Alzheimer's disease (AD) is the most common cause of dementia among the elderly and is characterized by loss of memory and other cognitive functions. An increase in AChE (a key enzyme in the cholinergic nervous system) levels around β-amyloid plaques and neurofibrillary tangles is a common feature of AD neuropathology. Amnesic effects of scopolamine (acetylcholine receptor antagonist...

The structure of malathion, S-[1,2-di(ethoxycarbonyl)ethyl] 00-dimethyl phosphorodithioate, has suggested to many investigators (e.g. Murphy & Dubois, 1957; Seume & O'Brien, 1960) that hydrolases may be involved in the synergism observed by Frawley, Fuyat, Hagan, Blake & Fitzhugh (1957) between malathion and O-ethyl O-p-nitrophenyl phenyl phosphorothioate. On the basis of their known substrate ...

Cryostat sections from 160 rectal suction biopsies were stained for cholinesterases by the method of Karnovsky and Roots (1964) in an attempt to facilitate the diagnosis of Hirschsprung's disease. The method proved at least as reliable as experienced assessment of paraffin haematoxylin-eosin sections, and appeared to offer the advantages of reduced scanning fatigue and superior demonstration of...

An early differentiation between AD and FTD may help choosing a therapeutic approach with cholinesterases inhibitors, which are restricted to AD, while for FTD there is no symptomatic or diseasemodifying therapy. Furthermore, both AD and FTD have significant implications for family members and a correct genetic counselling is largely dependent on a correct diagnosis. Lastly, AD and FTD have dif...

A 20-year-old male who attempted suicide by injecting subcutaneously 10 ml of Sistemin 40 (40% dimethoate) was admitted 16 h later. General weakness, muscular fibrillations and a marked inhibition of red blood cell and serum cholinesterases were the prominent signs of intoxication. The antidotal treatment of intermittent boluses of atropine, oxime HI-6 and diazepam was combined with symptomatic...

BACKGROUND Organophosphorus compounds (OP) are a group of substances used in agriculture as pesticides and are also used as military poisoning agents (MPA). Intoxication by these agents may cause severe systemic disturbances related to both the exposure time and lethal agent concentration. Toxic effects result from an excess of the endogenous neurotransmitter, acetylcholine (ACh), because decom...