HYPOKALAEMIA IN ORGANOPHOSPHOROUS COMPOUND POISONING

ABSTRACT Bioassays are little used to detect individual toxins in the environment because, compared to analytical methods, these assays are still limited by several problems, such as the sensitivity and specificity of detection. We tentatively solved these two drawbacks for detection of anatoxin-a(s) by engineering an acetylcholinesterase to increase its sensitivity and by using a combination of mutants to obtain increased analyte specificity. Anatoxin-a(s), a neurotoxin produced by some freshwater cyanobacteria, was detected by measuring the inhibition of acetylcholinesterase activity. By using mutated enzyme, the sensitivity of detection was brought to below the nanomole-per-liter level. However, anatoxin-a(s) is an organophosphorous compound, as are several synthetic molecules which are widely used as insecticides. The mode of action of these compounds is via inhibition of acetylcholinesterase, which makes the biotest nonspecific. The use of a four-mutant set of acetylcholinesterase variants, two mutants that are sensitive to anatoxin-a(s) and two mutants that are sensitive to the insecticides, allows specific detection of the cyanobacterial neurotoxin.

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Effects of an organophosphorous compound on cardiac rhythm and haemodynamics in anaesthetized and conscious beagle dogs

Toxicology Letters ◽

10.1016/0378-4274(87)90173-1 ◽

1987 ◽

Vol 37 (1) ◽

pp. 95-102 ◽

Cited By ~ 16

Author(s):

P. Robineau ◽

P. Guittin

Keyword(s):

Cardiac Rhythm ◽

Beagle Dogs ◽

Organophosphorous Compound

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Influence of cholinergic and adrenergic blocking drugs on hyperglycemia and brain glycogenolysis in diazinon-treated animals

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y88-188 ◽

1988 ◽

Vol 66 (8) ◽

pp. 1144-1147 ◽

Cited By ~ 15

Author(s):

K. Husain ◽

R. A. Ansari

Keyword(s):

Glycogen Phosphorylase ◽

Glycogen Content ◽

Organophosphorous Compound ◽

Adrenergic Blocking ◽

The Brain

Diazinon, an organophosphorous compound, produced hyperglycemia and reduced the glycogen content of the brain 2 h after its administration to rats (40 mg/kg, i.p.). The activities of the glycogenolytic enzymes, glycogen phosphorylase and phosphoglucomutase, were significantly increased, while that of glucose-6-phosphatase was not altered. Atropine (20 mg/kg, i.p.) given immediately after diazinon abolished the changes; tolazoline or propranolol (each at 10 mg/kg, i.p.) injected 30 min before the administration of diazinon significantly reduced the hyperglycemia and the increase in brain glycogenolysis. A combination of tolazoline and propranolol was more effective than either of them alone and completely abolished the hyperglycemia and the changes in brain glycogenolysis. It may be concluded that diazinon initially activates central cholinergic processes leading to hyperglycemia and increased cerebral glycogenolysis in animals.

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Clinico-Epidemiological Study of Self-Poisoning by Different Pharmaceutical Agents

Journal of Shaheed Suhrawardy Medical College ◽

10.3329/jssmc.v8i1.31499 ◽

2017 ◽

Vol 8 (1) ◽

pp. 17-22

Author(s):

Habib Ahmed ◽

Ferdousi Rahman ◽

Mahbubur Rahman ◽

Mohammad Enamul Karim ◽

Sayeda Rahim ◽

...

Keyword(s):

Urban Area ◽

Urban Areas ◽

Previous History ◽

Socioeconomic Background ◽

Tertiary Level ◽

Organophosphorous Compound ◽

History Of ◽

Pharmaceutical Agents ◽

Age Range ◽

Level Hospital

Background: In Bangladesh self-poisoning cases are mostly of organophosphorous compound (OPC). It is documented that 14% of all deaths amongst 10 to 50 year old women in Bangladesh were due to poisoning, the majority following suicidal ingestion of pesticides. In tertiary level hospital, a large number of self-poisoning cases are of different pharmaceutical agents, mostly from urban areas and mostly of teenager group. So the trend of self-poisoning is different in urban area than that of rural area. These pharmaceutical agent self-poisoning cases admitted into the hospitals have different modalities of clinical features with variable outcomes and socioeconomic background. But there is no actual data of these self-poisoning by the different pharmaceutical agents. Therefore, this study was aimed to describe the pattern of self-poisoning by different pharmaceutical agents.Methods: A descriptive longitudinal study was conducted in five adult medicine units of a tertiary level hospital from January 2008 to June 2008. All self-poisoned patients with different pharmaceutical agents were included with their prior informed written consent. A pre-tested questionnaire was used for data collection.Results: A total of 281 patients were interviewed. Most of the patients were female (70.8%) with highest age range from 13 to 30 years (91.81%). Most of the patients were students (53%) and 40.9% were secondary school certificate pass. 60.1% patients were unmarried. Most of the patients were from urban area (84%). The commonest background for self-poisoning was family disharmony (74.46%). Most common offending pharmaceutical agents were benzodiazepines (44.10%), collected mostly from local dispensary without prescription (89.33%). Most of the patients consulted within 1 to 2 hours of poisoning (44.5%). Commonest consultation before admission was in a Government hospital (48.40%). Only 3 patients (1.10%) were known to have psychiatric illness. Five patients (1.80%) had previous history of self-poisoning. Most of the patients (89.3%) stayed in the hospital for 1 day with no mortality.Conclusion: Self poisoning by pharmaceutical agents is common especially in urban areas. Common offending pharmaceutical agents were benzodiazepines. The commonest background for self-poisoning was family disharmony.J Shaheed Suhrawardy Med Coll, June 2016, Vol.8(1); 17-22

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Self-assembly of acetylcholinesterase on gold nanoparticles electrodeposited on graphite

Open Chemistry ◽

10.2478/s11532-013-0307-3 ◽

2013 ◽

Vol 11 (11) ◽

pp. 1740-1748 ◽

Cited By ~ 4

Author(s):

Nina Dimcheva ◽

Elena Horozova ◽

Yavor Ivanov ◽

Tzonka Godjevargova

Keyword(s):

Gold Nanoparticles ◽

Self Assembly ◽

Enzyme Inhibitors ◽

Gold Nanostructures ◽

Electrochemical Biosensors ◽

Organophosphorous Compound ◽

Enzyme Immobilisation ◽

Prospective Application ◽

Acetylcholinesterase Enzyme

AbstractThe immobilisation of AChE enzyme through chemisorption on Au-modified graphite was examined with view of its prospective application in the design of membraneless electrochemical biosensors for the assay of enzyme inhibitors. The developed immobilisation protocol has been based on a two-stage procedure, comprising i) electrodeposition of gold nanostructures on spectroscopic graphite; followed by ii) chemisorption of the enzyme onto gold nanoparticles. Both the coverage of the electrode surface with Au nanostructures and the conditions for enzyme immobilisation were optimised. The proposed electrode architecture together with the specific type of enzyme immobilisation allow for a long-term retaining of the enzyme catalytic activity. The extent of inhibition of the immobilised acetylcholinesterase enzyme by the organophosphorous compound monocrotophos has been found to depend linearly on its concentration over the range from 50 to 400 nmol mL−1 with sensitivity 77.2% inhibition per 1 µmol mL−1 of monocrotophos.

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