Searched for: subject%3A%22Cholinesterase%22
(1 - 20 of 49)

Pages

document
de Koning, M.C. (author), Joosen, M.J.A. (author), Worek, F. (author), Nachon, F. (author), van Grol, M. (author), Klaassen, S.D. (author), Alkema, D.P.W. (author), Wille, T. (author), de Bruijn, H.M. (author)
Recently, a new class of reactivators of chemical warfare agent inhibited acetylcholinesterase (AChE) with promising in vitro potential was developed by the covalent linkage of an oxime nucleophile and a peripheral site ligand. However, the complexity of these molecular structures thwarts their accessibility. We report the compatibility of...
article 2017
document
Reinen, J. (author), Nematollahi, L. (author), Fidder, A. (author), Vermeulen, N.P.E. (author), Noort, D. (author), Commandeur, J.N.M. (author)
Tri-ortho-cresyl phosphate (ToCP) is a multipurpose organophosphorus compound that is neurotoxic and suspected to be involved in aerotoxic syndrome in humans. It has been reported that not ToCP itself but a metabolite of ToCP, namely, 2-(ortho-cresyl)-4H-1,2,3-benzodioxaphosphoran-2-one (CBDP), may be responsible for this effect as it can...
article 2015
document
Johnson, D. (author), Carter, M.D. (author), Crow, B.S. (author), Isenberg, S.L. (author), Graham, L.A. (author), Erol, H.A. (author), Watson, C.M. (author), Pantazides, B.G. (author), van der Schans, M.J. (author), Langenberg, J.P. (author), Noort, D. (author), Blake, T.A. (author), Thomas, J.D. (author), Johnson, R.C. (author)
Tri-ortho-cresyl phosphate (ToCP) is an anti-wear, flame retardant additive used in industrial lubricants, hydraulic fluids and gasoline. The neurotoxic effects of ToCP arise from the liver-activated metabolite 2-(o-cresyl)-4H-1,3,2-benzodioxaphosphoran-2-one (cresyl saligenin phosphate or CBDP), which inhibits esterase enzymes including...
article 2015
document
de Koning, M.C. (author), van Grol, M. (author), Noort, D. (author)
Commonly employed pyridinium-oxime (charged) reactivators of nerve agent inhibited acetylcholinesterase (AChE) do not readily pass the blood brain barrier (BBB) because of the presence of charge(s). Conversely, non-ionic oxime reactivators often suffer from a lack of reactivating potency due to a low affinity for the active site of AChE. It was...
article 2011
document
van der Meer, J.A. (author), Trap, H.C. (author), Noort, D. (author), van der Schans, M.J. (author), TNO Defensie en Veiligheid (author)
Recently, several methods have been developed to verify exposure to nerve agents. Most of these methods, such as the fluoride reactivation technique and the analysis of inhibited phosphonylated butyrylcholinesterase (BuChE), are based on mass spectrometry. The high specificity of the mass spectrometer might also imply a disadvantage, because the...
article 2010
document
Joosen, M.J.A. (author), Jousma, E. (author), van den Boom, T.M. (author), Kuijpers, W.C. (author), Smit, A.B. (author), Lucassen, P.J. (author), van Helden, H.P.M. (author), TNO Defensie en Veiligheid (author)
To date, treatment of organophosphate (OP) poisoning shows several shortcomings, and OP-victims might suffer from lasting cognitive deficits and sleep–wake disturbances. In the present study, long-term effects of soman poisoning on learning ability, memory and neurogenesis were investigated in rats, treated with the anticholinergic atropine and...
article 2009
document
TNO Defensie en Veiligheid (author), Tuin, A.W. (author), Mol, M.A.E. (author), van den Berg, R.M. (author), Fidder, A. (author), van der Marel, G.A. (author), Overkleeft, H.S. (author), Noort, D. (author)
Elucidation of noncholinesterase protein targets of organophosphates, and nerve agents in particular, may reveal additional mechanisms for their high toxicity as well as clues for novel therapeutic approaches toward intoxications with these agents. Within this framework, we here describe the synthesis of the activity-based probe 3, which...
article 2009
document
TNO Defensie en Veiligheid (author), Langenberg, J.P. (author), van der Schans, M.J. (author), Noort, D. (author)
The perceived threat of the use of nerve agents by terrorists against civilian targets implies the need for methods for point-of-care (POC) diagnosis. This review presents an overview of methods that are currently available for the assessment of exposure to nerve agents. Since these methods are mostly MS based, they require complex and expensive...
article 2009
document
Noort, D. (author), Fidder, A. (author), van der Schans, M.J. (author), Hulst, A.G. (author), TNO Defensie en Veiligheid (author)
We present a generic mass spectrometric method to verify exposure to organophosphates, based on the chemical conversion of the phosphylated peptides obtained after pepsin digestion of human butyrylcholinesterase (HuBuChE) to a common precursor peptide. After exposure of plasma to various organophosphates (nerve agents, pesticides), HuBuChE was...
article 2006
document
Sweeney, R.E. (author), Langenberg, J.P. (author), Maxwell, D.M. (author), TNO Defensie en Veiligheid (author)
A physiologically based pharmacokinetic (PB/PK) model has been developed in advanced computer simulation language (ACSL) to describe blood and tissue concentration-time profiles of the C(±)P(-) stereoisomers of soman after inhalation, subcutaneous and intravenous exposures at low (0.8-1.0 × LD50), medium (2-3 × LD50) and high (6 × LD50) levels...
article 2006
document
Degenhardt, C.E.A.M. (author), Pleijsier, K. (author), van der Schans, M.J. (author), Langenberg, J.P. (author), Preston, K.E. (author), Solano, M.I. (author), Maggio, V.L. (author), Barr, J.R. (author), Prins Maurits Laboratorium TNO (author)
One of the most appropriate biomarkers for the verification of organophosphorus nerve agent exposure is the conjugate of the nerve agent to butyrylcholinesterase (BuChE). The phosphyl moiety of the nerve agent can be released from the BuChE enzyme by incubation with fluoride ions, after which the resulting organophosphonofluoridate can be...
article 2004
document
van Helden, H.H.P.M. (author), Vanwersch, R.A.P. (author), Kuijpers, W.C. (author), Trap, H.C. (author), Philippens, I.H.C. (author), Benschop, H.P. (author), Prins Maurits Laboratorium TNO (author)
The main purpose of this pilot study was to estimate the lowest observable adverse effect level (LOAEL) for the electroencephalogram (EEG) upon long-term, low-level exposure of vehicle-pretreated and pyridostigmine-pretreated marmoset monkeys to sarin vapour. This is the C·t value (t = 5 h) of exposure at which the EEG becomes significantly...
article 2004
document
Smulders, C.J.G.M. (author), Bueters, T.J.H. (author), Vailati, S. (author), van Kleef, R.G.D.M. (author), Vijvergberg, H.P.M. (author)
Chronic and acute exposure to organophosphate (OP) pesticides may lead to persistent neurological and neurobehavioral effects, which cannot be explained by acetylcholinesterase (AChE) inhibition alone. It is suggested that other brain proteins are involved. Effects of commonly used organophosphate pesticides on rat neuronal α4β2 nicotinic...
article 2004
document
Prins Maurits Laboratorium TNO (author), van der Schans, M.J. (author), Polhuijs, M. (author), van Dijk, C. (author), Degenhardt, C.E.A.M. (author), Pleijsier, K. (author), Langenberg, J.P. (author), Benschop, H.P. (author)
The utility was explored of a new approach to detect retrospectively exposure to nerve agents by means of conversion of the inhibitor moiety bound to the active site of the enzyme BuChE in plasma with fluoride ions into a phosphofluoridate which is subsequently analyzed by means of gas chromatography (GC). This quantifies ≥0.01% inhibition of...
article 2004
document
Bajgar, J. (author), Ševelová, L. (author), Krejčová, G. (author), Fusek, J. (author), Vachek, J. (author), Kassa, J. (author), Herink, J. (author), de Jong, L.P.A. (author), Benschop, H.P. (author)
Soman belongs to the most dangerous nerve agents because of the low effectiveness of the presently available antidotes. Soman acts by inhibiting acetylcholinesterase (AChE) both peripherally and centrally, with a subsequent accumulation of neuromediator acetylcholine and other metabolic changes. From the data published in literature it can be...
article 2004
document
van Helden, H.P.M. (author), Trap, H.C. (author), Oostdijk, J.P. (author), Kuijpers, W.C. (author), Langenberg, J.P. (author), Benschop, H.P. (author), Prins Maurits Laboratorium TNO (author)
Realistic scenarios for low-level exposure to nerve agents will often involve exposures over several hours to extremely low doses of agent. In order to expose animals to the lowest controllable concentrations of agent and to increase exposure times until a lowest observable effect level (LOEL) becomes measurable, a validated system was developed...
article 2003
document
Prins Maurits Laboratorium TNO (author), Smulders, C.J.G.M. (author), Bueters, T.J.H. (author), van Kleef, R.G.D.M. (author), Vijverberg, H.P.M. (author)
Effects of commonly used carbamate pesticides on rat neuronal nicotinic acetylcholine receptors expressed in Xenopus laevis oocytes have been investigated using the two-electrode voltage clamp technique. The potencies of these effects have been compared to the potencies of the carbamates to inhibit rat brain acetylcholinesterase. The potency...
article 2003
document
Smit, L.A.M. (author), van Wendel- de Joode, B.N. (author), Heederik, D. (author), Peiris-John, R.J. (author), van der Hoek, W. (author)
Background: In many agricultural districts in Sri Lanka, pesticide poisoning is a leading cause of death. This study aims to evaluate the impact of pesticide use on Sri Lankan farmers' health. Methods: A total of 260 subjects were surveyed in both a low and a high exposure period. Acetylcholinesterase activity was measured and data on symptoms...
article 2003
document
Noort, D. (author), Benschop, H.P. (author), Black, R.M. (author), Prins Maurits Laboratorium TNO (author)
In this report an overview of the methods currently available for detection of exposure to a number of chemical warfare agents (CWA), i.e., sulfur mustard, lewisite and nerve agents, is presented. Such methods can be applied for various purposes, e.g., diagnosis and dosimetry of exposure of casualties, confirmation of nonexposure, verification...
article 2002
document
Fidder, A. (author), Hulst, A.G. (author), Noort, D. (author), de Ruiter, R. (author), van der Schans, M.J. (author), Benschop, H.P. (author), Langenberg, J.P. (author), Prins Maurits Laboratorium TNO (author)
In this paper a novel and general procedure is presented for detection of organophosphate-inhibited human butyrylcholinesterase (HuBuChE), which is based on electrospray tandem mass spectrometric analysis of phosphylated nonapeptides obtained after pepsin digestion of the enzyme. The utility of this method is exemplified by the positive analysis...
article 2002
Searched for: subject%3A%22Cholinesterase%22
(1 - 20 of 49)

Pages