• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2189-2198
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• 2014

Paraquat (PQ) is a very effective and widely used herbicide that was commercially introduced in 1962. In this study, instead of using antioxidants like in the past, to inhibit the formation of PQ-induced ROS, we attempted to reduce the oxygen concentration by using non-lethal hypoxia therapy. Therefore, we studied the toxicity of PQ in vivo, analyzed the major effects of ROS on the targeted lung tissue and compared the results with the gross histological changes after the cell protective effect of non-lethal hypoxia therapy. In vivo studies demonstrated that low-concentration oxygen therapy (i.e., 10-12% oxygen) in rats administered with PQ was associated with a higher survival rate than in rats that received only PQ. In vivo non-lethal hypoxia treatment showed better survival and less lung tissue damage. Using a hypoxic/anaerobic incubator with integrated multifaceted molecular analysis, including MDA assay, glutathione assay, and SOD assay, we established an optimal, significantly reduced in vivo non-lethal hypoxia treatment by exploiting the PQ-induced cytotoxicity responses.

• Tuberculosis and Respiratory Diseases
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• v.62 no.2
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• pp.113-118
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• 2007

Background: Paraquat is known to induce oxidant injury that results in multiorgan failure and lung fibrosis. Iron has been considered to play a key role in paraquat-induced oxidant lung injury. This study examined the effect of deferoxamine, an iron-chelating agent, in the treatment of paraquat poisoning. Methods: From September, 2001 to April, 2005, 28 patients with paraquat poisoning who were admitted at a medical intensive care unit of a University-affiliated hospital, were enrolled in this study. Sixteen patients were treated according to the paraquat poisoning treatment guidelines and 12 received an intravenous infusion of deferoxamine in addition to the treatment guidelines. Results: There were no differences between the two groups in terms of age, gender, severity of paraquat poisoning, and the time elapsed from ingestion to presentation at hospital. There was no difference in overall mortality between the two groups but the incidence of respiratory failure in the deferoxamine group was higher than in the conventional group(4/7 versus 0/9, p=0.019). Conclusion: Deferoxamine seems to have no clinical benefit compared with the conventional treatment.

• Journal of Veterinary Clinics
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• v.19 no.3
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• pp.379-382
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• 2002

A patient (Pointer+Viszula mixed breed, 4 months old, male), with chief historic sign of acute vomiting, hemorrhagic diarrhea, anorexia and dyspnea during 4 days was admitted to College of Veterinary Medicine, Kyungpook National University. Necropsy findings were revealed ulcer and hemorrhage contained hemorrhagic diarrhea in gastrointestinal tract, severe emphysema and hemorrhage in the lung and kidney and cardiac hypertropy. Histopathological changes showed emphysema, hyperemia and hemorrhage in the lung, severe hyperemia, hemorrhage, hepatic vacuolation and cellular necrosis in the liver, hyperemia, hemorrhage, necrosis of tubular epithelium in the kidney, hemorrhage in cardiac muscle and hyperemia, necrosis and sloughing of epithelium in the intestine. Histopathological diagnosis was made as paraquat poisoning.

• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.339-344
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• 2003

Paraquat is an effective and widely used herbicide, but it is also very toxic to humans. It is well-known that urine paraquat concentration is one of the most important prognostic indicator for paraquat-poisoning. Quantitative analysis of paraquat, however, are not generally used in clinical laboratories. In this work, a new test strip to detect paraquat concentration using sodium dithionite in urine was developed. Using these second-derivative method, the test strip prepared in $0.5{\%}$ borate buffer (pH 8.0), 0.25 M $Na_2S_2O_4,\0.1~0.8{\%}$ PVP, and $1{\%}$ decanol showed not only better color reaction but also an excellent application possibility to be used in automatic analyzer.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1232_1233
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• 2009

Paraquat is well-known to cause hepatotoxic responses in human and other mammal species. In solution, it forms free radicals and charge-transfer complex of which formation plays an important role in determination of its biological activity in the presence of various anions. The HepG2 cells were cultured onto a quartz crystal sensor which is possible to detect the density and a viscosity changes using the resonance frequency (F) and the resonance resistance (R). The plot of F-R diagram is able to explain the rheological change of cells onto the surface of the quartz crystal sensor. In this paper, we investigated the physical properties of the HepG2 cells cultured onto a ITO electrode of the quartz crystal sensor according to the paraquat injection at various concentrations (100 mM, 10 mM, 1 mM). We also observed the morphological changes with a micro CCD camera, simultaneously. The HepG2 cells were cultured onto the ITO electrode surface of the quartz crystal modified a collagen film in $CO_2$ incubator. After the paraquat injection, we observed the changes of the morphologies by the micro CCD camera depending on time and analyzed the physical changes of cells on the electrode surface of quartz crystal using F-R diagram. From all results, we proved the effect of paraquat at various concentrations which is led to an apoptosis such as weakening and death of the cells by oxidation and reduction reaction that were produced the superoxide anions and other free radicals.

• Journal of Trauma and Injury
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• v.26 no.1
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• pp.6-13
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• 2013

Purpose: Sulforaphane is a naturally-occurring isothiocyanate abundant in broccoli. It has been suggested as a promising antioxidant. In this study, the therapeutic effect of sulforaphane in paraquat intoxication was investigated. Methods: Paraquat was administered via the tail vein, after which sulforaphane or a vehicle (4% DMSO) was administered intraperitoneally 15 minutes after paraquat administration. Histological injury, lipid peroxidation, plasma cytokine (IL-6, IL-10), and nitric oxide were measured. In addition, the effect of sulforaphane on survival in paraquat-intoxication was observed. Results: Regarding histological injury, lipid peroxidation, and plasma cytokine and nitric-oxide response, sulforaphane administration showed no protective effects in paraquat-intoxicated rats. Rather, it increased mortality (log rank p=0.03) and caused lipid peroxidation, as well as plasma cytokine and nitric-oxide production, to be increased. Conclusion: Sulforaphane had no therapeutic effect on paraquat-intoxicated rats; rather, it increased mortality.

• Journal of The Korean Society of Clinical Toxicology
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• v.9 no.1
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• pp.14-19
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• 2011

Purpose: Most paraquat poisonings are easily diagnosed by history taking on physical examination, however, some are failed to be diagnosed initially if the poisoning was veiled. The purpose of this study was to explore the clinical characteristics of veiled paraquat poisoning. Methods: We retrospectively reviewed the medical records of patients whose discharge diagnosis was paraquat poisoning in one university teaching hospital between 1 Jan, 2001 and 31 Dec, 2010. Veiled paraquat poisoning was determined when there was a positive urine paraquat kit in patients who did not mention paraquat poisoning in an initial physical examination or had unknown cause of pulmonary fibrosis, acute renal failure, or multi-organ failure. Results: Of the 117 patients with paraquat poisoning during the study period, 6 patients (5.1%) had veiled paraquat poisoning. The clinical characteristics were 1) proteinuria - 6 (100%), 2) increased creatinine - 4 (66.7%), 3) green skin stains - 2 (33.3%), 4) mucosal ulcer - 3 (50%). Blood chemistry results were variable. Conclusion: We should suspect veiled paraquat poisoning for patients who have proteinuria, increased creatinine, green skin stain, mucosal ulcer and vomiting, or if they have rapidly progressing acute renal failure or multi-organ failure with unknown cause, even if patients didn't mention about paraquat poisoning upon the initial physical examination. In cases with the above clinical conditions, a thorough repeated physical examination including history taking and use of urine paraquat kits should be performed.

• Journal of The Korean Society of Clinical Toxicology
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• v.3 no.2
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• pp.122-125
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• 2005

Paraquat, is a widely used for its great effect as a herbicide. But the mortality rate by paraquat intoxication is known to be very high. It is thought to act by changing form to superoxide and peroxide free radical. Almost paraquat intoxication is through ingestion. A few intoxication of paraquat is through skin absorption. But there was no known death case through skin absorption. We experienced a case of a expired patient by paraquat intoxication through skin abrasion and scratching wound. A 75-year-old man was visited emergency room after motorcycle accident during transporting paraquat. He has multiple abrasion and scratching wound on extremities, and pelvic bone fracture. There was no evidence of ingestion of paraquat. But serum/urine gramoxone level was all positive. In spite of wound irrigation and hemoperfusion, his condition was been gone form bed to worse. 2 days after, multiple organ failure and the respiratory arrest were developed and he was expired. Paraquat intoxication through skin wound is extremely dangerous and death by that could possibly happen

• Journal of The Korean Society of Clinical Toxicology
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• v.6 no.2
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• pp.130-133
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• 2008

In South Korea, attempted suicide by paraquat (PQ) intoxication is fairly common, and is lethal by pulmonary fibrosis and hypoxemia. However, the treatment of PQ poisoning is primarily supportive management. To increase the survival rate associated with PQ intoxication, many treatments have been developed. Here, we treated a case of PQ intoxication with steroid pulse therapy. A 23-year-old man was admitted to the hospital because of PQ intoxication. He drank two mouthfuls of Gramoxon (24% commercial paraquat). His vital signs were stable, but he had a throat infection, and navy blue urine in the sodium dithionite test. Standard treatment, including gastric lavage with activated charcoal was performed, and emergent hemoperfusion with a charcoal filter was initiated 11 h after PQ ingestion. Pharmacotherapy was initiated 18 h after PQ ingestion with the administration of 5 mg dexamethasone. On day 10, chest PA showed pulmonary fibrosis. Therefore, we initiated steroid pulse therapy, with 1g methylprednisolone in 100 mL of D5W administered over 1 h repeated daily for 3 days, and 1 g cyclophosphamide in 100 mL of D5W administered over 1 h daily for 2 days. On day 15, dexamethasone therapy was initiated. On day 30, pulmonary fibrosis was improved. Thus, if pulmonary fibrosis becomes exacerbated after dexamethasone therapy during the subacute stage, pulse therapy with methylprednisolone and cyclophosphamide could be helpful.

• Journal of Trauma and Injury
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• v.18 no.1
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• pp.53-63
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• 2005

Purpose: This study was designed to determine if methylene blue inhibited the lipid peroxidation, the production of NO, and the gene expression of iNOS in acute lung injury induced by paraquat and if the inhibitory effect was dose dependent. Methods: Female Sprague-Dawley rats were divided into four groups: the control group, the group treated with paraquat only, the group treated with paraquat and a low dose of methylene blue (2 mg/kg), and the group treated with paraquat and a high dose of methylene blue (20 mg/kg). Methylene blue was administered via the jugular vein 1 h after paraquat administration, and animals were sacrificed 6 and 24 h after paraquat administration. Malondialdehyde (MDA) as lipid peroxidation, reduced glutathione (GSH) as an antioxidant defense, the plasma NO concentration, and the expression of iNOS mRNA in the lung tissue were measured Results: Lung MDA contents decreased, with no significant difference between the methylene-blue groups and the paraquat-only group. Lung GSH contents were significantly elevated at 24 h in the methylene-blue groups compared with the paraquat-only group. Plasma NO concentrations were significantly reduced at 6 and 24 h in the methylene-blue groups compared with the paraquat-only group. There was also a significant decrease in the plasma NO concentration at 6 h in the high-dose methylene-blue group compared with the low-dose methylene-blue group. The expression of iNOS mRNA in the lung tissue was slightly decreased in the methylene-blue groups. It was also markedly increased at 24 h in the paraquat-only group compared with the methylene-blue groups. The gene expression was relatively decreased in the high-dose methylene-blue group compared with the low-dose methylene-blue group. Conclusion: This study suggests that methylene blue has an inhibitory effect on the plasma NO concentration and the expression of iNOS mRNA in lung injury induced by paraquat. No inhibitory effect of methylene blue on lipid peroxidation or dose-dependent inhibitory effects were clearly shown.