Search results for "Cholinesterases"
showing 10 items of 16 documents
Pseudocholinesterases and human red cell acid phosphatases in Koreans.
1969
The authors reveal the results of pseudocholinesterase and human red cell acid phosphatase typings in a sample of 115 unrelated female Koreans aged from 20–30. No atypical pseudocholinesterase variants could be demonstrated. The frequencies of human red cell acid phosphatase alleles run up to: phA=0.231, phB=0.769, phC=0.000.
Parallel reduction of plasma levels of high and low molecular weight kininogen in patients with cirrhosis
1999
SummaryLittle is known about the regulation of high-molecular-weight-kininogen (HK) and low-molecular-weight-kininogen (LK) or the relationship of each to the degree of liver function impairment in patients with cirrhosis. In this study, we evaluated HK and LK quantitatively by a recently described particle concentration fluorescence immunoassay (PCFIA) and qualitatively by SDS PAGE and immunoblotting analyses in plasma from 33 patients with cirrhosis presenting various degrees of impairment of liver function. Thirty-three healthy subjects served as normal controls. Patients with cirrhosis had significantly lower plasma levels of HK (median 49 μg/ml [range 22-99 μg/ml]) and LK (58 μg/ml [15…
Cholinesterase variants: rapid characterisation by PCR/SSCP and evidence for molecular homogeneity.
1995
We have applied the technique of PCR-SSCP (polymerase chain reaction-single stranded conformation polymorphism) to characterise the molecular basis of cholinesterase deficiency and variants in a Jordanian family. PCR-SSCP proved to be a quick and sensitive method of screening cholinesterase variants in a clinical setting. An AG insertion at position 351 was found to cause a silent allele, for which the parents were heterozygous and three children homozygous. In addition, the father and two sons were heterozygous for an A to G transition at position 209, known to cause the dibucaine resistant variant. No linkage to the K variant was found, which has been reported previously in white populati…
External and internal exposure of wine growers spraying methyl parathion.
2005
Organophosphates, used in agriculture, are readily absorbed through the skin. We investigated the relationship between dermal and inhalative methyl parathion exposure and the plasma levels. Twenty-three healthy wine growers sprayed the insecticide for 50 min. Fluorescent brilliant sulfoflavin was added to the spraying fluids and filter papers were fixed on the subjects. The filter papers were used to evaluate the amount of brilliant sulfoflavine on the unprotected skin fluorometrically. Inhalative exposure was measured with personal air sampler. Plasma concentrations of methyl parathion and its metabolite methyl paraoxon were determined with gas chromatography. Cholinesterase activity in se…
End-plate dysfunction in acute organophosphate intoxication.
1989
Acute organophosphate intoxication resulting from suicide attempts in 14 patients produced a series of electrophysiologic abnormalities that correlated with the clinical course. Spontaneous repetitive firing of single evoked compound muscle action potentials (CMAP) was the earliest and most sensitive indicator of the acetylcholinesterase inhibition. A decrement of evoked CMAP following repetitive nerve stimulation was the most severe abnormality. At the height of the intoxication no CMAP was evoked after the first few stimuli. The decrement-increment phenomenon occurred only at milder stages of intoxication and its features are characteristic of acetylcholinesterase inhibition. These electr…
On the geographical distribution of pseudocholinesterase variants.
1975
The incidence of pseudocholinesterase (PCHE equals E.C. 3.1.1.8) variants in samples of 8 different population (total of 2218 individuals) is reported. Together with previously mentioned data from the literature, a general survey on the geographical distribution of PCHE isoenzymes is given. Possible reasons for present-day heterogeneity of their distribution are also discussed. Concerning the incidence of the C5 variant, it is pointed out that the validity of applying population genetic models depends upon the accuracy of the genetic basis.
Cholinesterase Activity and Hematological Parameters as Biomarkers of Sublethal Molinate Exposure in Anguilla anguilla
2000
Cholinesterase (ChE) activity was measured in plasma, whole blood [using 5,5'-dithiobis(2-nitrobenzoic acid) and 2-PDS as chromophores], brain, and whole eyes of Anguilla anguilla exposed to a sublethal concentration of 11.15 mg/L (one-third of the 96-h LC(50)) of the carbamate herbicide molinate. ChE activity was evaluated after 6, 24, 48, 72, and 96 h of pesticide exposure. Results indicated that ChE activity in eel tissues decreased as time of exposure increased, especially in eel blood. Eels exposed to molinate were transferred to a pesticide-free water for a recovery period of 4 days and ChE activity was also evaluated. Results indicated that ChE activity for those animals with preexpo…
Frequencies of pseudocholinesterase variants in Icelanders, Greeks and Pakistanis.
1968
THE formation of the human pseudocholinesterase variants is controlled by at least four alleles at one autosomal locus termed E1 (ref. 1). The four alleles are , , and (refs. 2–5). The heterozygotes have been found in remarkably uniform frequencies, about 3 to 6 per cent, in Caucasians from Europe and North America3,8–11, and also in Australian aborigines12 and Mexican Indians13, but are relatively rare among Negroes11 and Mongoloids10,11,14.
Acute toxicity of dichlorvos to Aphanius iberus (Cuvier & Valenciennes, 1846) and its anti-cholinesterase effects on this species
2008
This study evaluates the toxic effects of the organophosphate pesticide (OP) dichlorvos to the endangered Iberian toothcarp (Aphanius iberus). To this end, the lethal toxicity of dichlorvos based on 96 h-LC50 bioassays was determined in saline water (50 g/L), and in vivo effects of dichlorvos on cholinesterase (ChE) activity were investigated in adult female and male specimens. The 96 h-LC50 value determined by probit analysis was 3.17 mg/L (95% confidence limits: 1.34-3.97). The characterisation of the ChE using different substrates and specific inhibitors was also carried out in head and muscle tissues. Acetylthiocholine was the substrate preferred by both head and muscle ChE in males and…
The effect of physostigmine on the vagally induced muscarinic inhibition of noradrenaline release from the isolated perfused rabbit atria.
1982
1. Presynaptic cholinergic-adrenergic interactions were studied on isolated perfused rabbit atria with the extrinsic right vagus and sympathetic innervation intact. The transmitter stores were labelled with 14C-choline and 3H-noradrenaline. The radioactive compounds were separated on columns and determined by scintillation spectrometry. The stimulation-evoked overflow of both transmitters was calcium-dependent and abolished by tetrodotoxin. 2. Methacholine caused a concentration-dependent decrease of atrial tension development and 3H-noradrenaline overflow evoked by 3 Hz sympathetic stimulation. Vagus nerve stimulation (1–20Hz), although nearly abolishing tension development at 20Hz, decrea…