Chemistry Techniques, Analytical ; instrumentation ; Herbicides ; analysis ; Humans ; Paraquat ; analysis

Biocompatible Materials ; analysis ; Chromatography ; methods ; Chromatography, Gas ; methods ; Chromatography, Liquid ; methods ; Paraquat ; analysis ; Pesticide Residues ; analysis

Air Pollutants ; analysis ; Chromatography, High Pressure Liquid ; methods ; Paraquat ; analysis ; Workplace

BACKGROUND: Activated charcoal has been widely used as an adsorbent for the management of drug intoxicated patients in the emergency department(ED). Although there are several commercial ready-mixed charcoal suspension preparations in the market, we are using custom-made suspension from hospital grade bulk charcoal powder. We designed this study to compare the adsorptive capacity of the Actidose Aqua(R), which is a commercial charcoal product, Fuller's earth, and custom-made activated charcoal used in our ED. METHODS: First, we performed modified USP methylene blue adsorption test which is a standard adsorption test for activated charcoal. Then, the drug adsorption test for phenobarbital, acetaminophen, salicylate, and aminophylline was done. Graded amount of three adsorptives were added to the stock solutions of each drugs. The adsorption test were performed as follows: The vials containing drugs and adsorptives were shaken for 30 minutes to ensure adsorption equilibrium, then the suspension was filtered through in-line filter. The filtrates were analyzed by ultraviolet spectroscopy to determine the residual drug concentrations. Finally we examined and compared the surface area and the structure of activated charcoal and Fuller's earth using scanning electron microscopy. RESULTS: In methylene blue adsorption test, the adsorption rate was 60.1% in Actidose Aqua(R) and 59.0% in custom-made charcoal, and 70.2% in Fuller's earth. For the phenobarbital, acetaminophen, and sallcylate, the adsorption rate of Actidose Aqua(R) and custom-made charcoal was greater than 90% with the ratio o adsorptives to drugs over 10:1. For aminophylline, two charcoal products showed excellent adsorption in 5:1 ratio. But Fuller's earth showed poor adsorption in all rages. CONCLUSION: Custom-made activated charcoal showed a comparable adsorption capacity to Actidose Aqua(R). Fuller's earth showed a poor performance to be used as a substitute for activated charcoal in acute drug poisoning otherwise paraquat.
Acetaminophen ; Adsorption ; Aminophylline ; Charcoal* ; Emergencies ; Humans ; Methylene Blue ; Microscopy, Electron, Scanning ; Paraquat ; Phenobarbital ; Poisoning ; Rage ; Spectrum Analysis

A 20-year-old male patient was admitted in our department 14 h after paraquat poisoning at the dose of about 50 mL. The patient underwent intensive hemoperfusion for 2 h (3 times a day) for 9 consecutive days and received continuous renal replacement therapy (CRRT) in the mode of continuous veno-venous hemofiltration (CVVH) for 10 consecutive days in addition to routine medications. The biochemical indexes were monitored during the therapy. After the treatment, paraquat concentrations in the blood and urine were decreased, and the patient's urine volume (UV) increased, serum creatinine (Cr) level decreased, and the oxygenation index became normal. Dynamic CT scan showed no obvious pulmonary fibrosis. The patient was followed up for 6 months after discharge and no complaint of discomforts was reported. This case suggests that early intensive hemoperfusion and long-term CVVH may help improve the prognosis after paraquat poisoning.
Blood Gas Analysis ; Blood Pressure ; Body Fluids ; Hemofiltration ; Hemoperfusion ; Humans ; Male ; Paraquat ; poisoning ; Poisoning ; therapy ; Prognosis ; Renal Dialysis ; Young Adult

OBJECTIVE: To establish an HPLC method for the determination of Paraquat in biological samples. METHODS: Paraquat in biological samples was extracted by C18 columns which were pre-treated with cetyl-trimethyl ammonium bromide (CTAB) and soudium dodecyl sulphate (SDS), and analysed by HPLC/DAD. RESULTS: The detection limit of the method was 1 ng x mL(-1), and the average recoveries were 81%-94%. CONCLUSION The method can be used to analysis of paraquat in biological samples.
Animals ; Chromatography, High Pressure Liquid/methods* ; Herbicides/chemistry* ; Liver/chemistry* ; Paraquat/analysis* ; Rabbits ; Sensitivity and Specificity ; Sodium Dodecyl Sulfate ; Solvents ; Swine

PURPOSE: Paraquat (1,1-dimethyl-4,4'-bipyridylium chloride) is widely a used non- selective herbicide. In spite of efforts to improve the outcome in patients poisoned with paraquat, the mortality rates still remains high. The purpose of this study is to identify initial stat laboratory parameters which can affect the survival rate of these patients. METHODS: A retrospective analysis by chart review was done on 67 patients who had ingested paraquat and who had presented to the Emergency Medical Center of Chonnam University Hospital from June 1997 to July 2001. RESULTS: The results were as follows: 1) Survivors were significantly younger than the nonsurvivors (38 years vs 44 years, p=0.03). The volume of paraquat ingested by survivors was significantly smaller than that ingested by the deceased (1 mouthful vs 3 mouthfuls, p<0.001). 2) The WBC count and the levels of serum AST, BUN and serum creatinine in the deceased were significantly higher than those in the survivors. The levels of serum potassium and bicarbonate, arterial pH, and base excess in survivors were significantly higher than those in the deceased. 3) A multivariate analysis revealed that serum creatinine, serum potassium, and arterial base excess were associated with the fatality rate. CONCLUSION: Initial stat laboratory parameters including arterial blood gas analysis, renal function test, and serum electrolytes could be used to predict the outcome of patients poisoned with paraquat. However, the development of readily applicable and reliable indices predicting outcome is desired for the future.
Blood Gas Analysis ; Creatinine ; Electrolytes ; Emergencies ; Humans ; Hydrogen-Ion Concentration ; Jeollanam-do ; Mortality ; Mouth ; Multivariate Analysis ; Paraquat* ; Potassium ; Retrospective Studies ; Survival Rate* ; Survivors

OBJECTIVETo investigate the protective effects of the tert-butylhydroquinone (tBHQ) pretreatment on neurotoxicity and oxidative stress induced by paraquat (PQ) in PC12 cells.

METHODSCytotoxicity of PC12 cells was measured by MTT assay, following the PC12 cells treatment with different concentrations of 100, 300 micromol/L PQ for 24 h and 48 h. PC12 cells were pretreated with or without 40 micromol/L tBHQ for 4 h, PC12 cells were exposed to PQ at the doses of 0, 100, 300 micromol/L for 24 h and 48 h, respectively. The viability of PC12 cells was measured by MTT assay, the apoptosis rates of PC12 cells were detected by flow cytometry (FCM) and the malondialdehyde (MDA) levels of PC12 cells were examine by thiobarbituric acid (TBA) method.

RESULTSWhen the exposure doses of PQ were 100 and 300 micromol/L for 24 h, the viability of PC12 cells pretreated with tBHQ was significantly higher than that of PC12 cells only exposed to PQ (P < 0.05 or P < 0.01). When the exposure dose of PQ was 100 micromol/L for 48 h, the viability of PC12 cells pretreated with tBHQ was significantly higher than that of PC12 cells only exposed to PQ (P < 0.01). When the exposure doses of PQ were 100 and 300 micromol/L for 24 h, the apoptosis rates and MDA levels of PC12 cells pretreated with tBHQ were significantly lower than those of PC12 cells only exposed to PQ (P < 0.05 or P < 0.01).

CONCLUSIONStBHQ pretreatment can reduce the cytotoxicity, apoptosis and oxidative stress induced by PQ in PC12 cells.

Animals ; Apoptosis ; drug effects ; Cell Survival ; drug effects ; Hydroquinones ; pharmacology ; Oxidative Stress ; drug effects ; PC12 Cells ; Paraquat ; toxicity ; Rats ; Reactive Oxygen Species ; analysis

Acute Disease ; Animals ; Ginkgo biloba ; Glutathione ; analysis ; Lung ; drug effects ; metabolism ; pathology ; Malondialdehyde ; analysis ; Paraquat ; toxicity ; Phytotherapy ; Plant Extracts ; therapeutic use ; Poisoning ; drug therapy ; Rats ; Superoxide Dismutase ; analysis ; Treatment Outcome

BACKGROUNDParaquat (PQ; 1, 1'-dimethyl-4, 4'-bipyridinium), a widely used herbicide that is structurally similar to the known dopaminergic neurotoxicant MPTP (1-methyl-1, 2, 3, 6-tetrahydropyridine), has been suggested as a potential etiologic factor for the development of Parkinson's disease (PD). Aging is an accepted risk factor for idiopathic Parkinson's disease. The aim of this study was to test the hypothesis that paraquat could induce PD-like nigrostriatal dopaminergic degeneration in aging C57BL/6 mice.

METHODSSenile male C57BL/6 mice were intraperitoneally injected with either saline or PQ at 2-day intervals for a total of 10 doses. Locomotor activity and performance on the pole test were measured 7 days after the last injection and animals were sacrificed one day later. Level of dopamine (DA) and its metabolites levels in the striatum were measured by high-performance liquid chromatography with an electrochemical detector (HPLC-ECD), and numbers of tyrosine hydroxylase (TH) positive neurons were estimated using immunohistochemistry.

RESULTSLocomotor activities were significantly decreased and the behavioral performance on the pole test were significantly impaired in the PQ treated group. Level of DA and its metabolites levels in the striatum were declined by 8 days after the last injection. Immunohistochemical analyses showed that PQ was associated with a reduction in numbers of tyrosine hydroxylase positive neurons.

CONCLUSIONSLong-term repeated exposes to PQ can selectively impair the nigrostriatal dopaminergic system of senile mice, suggesting that PQ could play an important role in the pathogenesis of Parkinson's disease (PD). Our results also validate a novel model of PD induced by exposure to a toxic environmental agent.

Aging ; pathology ; Animals ; Corpus Striatum ; drug effects ; Disease Models, Animal ; Dopamine ; analysis ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Motor Activity ; drug effects ; Paraquat ; toxicity ; Parkinson Disease, Secondary ; chemically induced ; Substantia Nigra ; drug effects ; enzymology ; Tyrosine 3-Monooxygenase ; analysis