Age group characteristics of children who visited the emergency department with acute poisoning by ingestion

PURPOSE: To investigate the age group characteristics of children who visited the emergency department with acute poisoning by ingestion. METHODS: We reviewed children under 19 years who visited the emergency department for acute poisoning by ingestion from 2012 to 2017. The children were divided into 3 age groups; infants (0-1 years), preschoolers (2-5 years), and schoolers (6-18 years). Clinical characteristics, intentional ingestion, involved substances (drugs, household products, artificial substances, and pesticides), decontamination and antidote therapy, and outcomes of the 3 age groups were compared. We also performed multivariable logistic regression analysis to identify factors associated with hospitalization. RESULTS: A total of 622 children with acute poisoning by ingestion were analyzed. Their annual proportions to overall pediatric emergency patients ranged from 0.3% to 0.4%. Age distribution showed bimodal peaks at 0-2 years and 15-17 years. The infants showed lower frequency of girls, intentional ingestion, ingestion of drugs, performance of decontamination and antidote therapy, and hospitalization than 2 older groups (P < 0.001). Most decontamination, antidote therapy, and hospitalization occurred in the schoolers (P < 0.001). The most frequently reported substances were household cleaning substances in the infants (18.2%), antihistamines in the preschoolers (15.8%), and analgesics in the schoolers (37.5%). The factors associated with hospitalization were intentional ingestion (adjusted odds ratio [aOR], 7.08; 95% confidence interval [CI], 2.85-17.61; P = 0.001) and schoolers (aOR, 2.33; 95% CI, 1.10-7.53; P = 0.031; compared with infants). Only 1 in-hospital mortality was found in a boy aged 2 years who ingested methomyl. CONCLUSION: Infants may experience non-intentional ingestion, ingestion of non-pharmacologic substances (especially household cleaning substances), discharge without decontamination and antidote therapy more frequently than older children. Thus, we need age group-specific, preventive and therapeutic plans for children with acute poisoning.

A Case of Methomyl-induced Acute Allergic Tubulointerstitial Nephritis

Drug-induced interstitial nephritis is one of the causes of acute kidney injury. Although methomyl is widely used as an insecticide in many countries, methomyl-induced interstitial nephritis has not been reported thus far in the general population. We report a case of a 39-year-old male patient with acute allergic tubulointerstitial nephritis due to methomyl intoxication. He took methomyl 250 mL to commit suicide. He was treated with hemodialysis, but his renal function continued to deteriorate. Kidney biopsy demonstrated mononuclear cell and some eosinophils infiltration into the renal interstitium with tubular invasion. Immediate steroid pulse therapy, appropriate education, and conservative management resulted in gradual restoration of his renal function. This case suggests that methomyl may be a causative allergen inducing acute interstitial nephritis in some patients.

acetylcholinesterase [AChE] inhibition analysis of medaka [Oryzias latipes] in the exposure of three insecticides

The continuous effects on Acetylcholinesterase [AChE] activity of medaka [Oryzias latipes] caused by dichlorvos, methomyl and deltamethrin in vivo were investigated, and the trends of AChE activity inhibition due to the influence of these insecticides were discussed. The LC[50]-24 h of dichlorvos, methomyl and deltamethrin on medaka were 2.3 mg/L, 0.2 mg/L, and 2.9×10[-3] mg/L respectively. The result suggested that at the beginning of the exposure, the AChE activity might increase, and the AChE activity in dead individuals was obviously lower than the live individuals. Though the de novo synthesis of AChE in medaka might help the AChE activity recover, the trends during the exposure in different treatments were downward, and it showed both exposure time and concentration dependent. Meanwhile, higher temperature might cause the AChE inhibition earlier due to the higher metabolic rate. Therefore, as a specific biomarker for organophosphate, carbamate pesticides and pyrethroids, the degree of the AChE inhibition with in vivo conditions is a good tool in continuous monitoring of insecticides, which may induce the nerve conduction disorders

Effects of methomyl on acetylcholinesterase in erythrocyte membrane and various brain areas / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the toxicity of methomyl to acetylcholinesterase (AChE) in different regions.</p><p><b>METHODS</b>The optimal temperature and time for measurement of AChE activity were determined in vitro. The dose- and time-response relationships of methomyl with AChE activity in human erythrocyte membrane, rat erythrocyte membrane, cortical synapses, cerebellar synapses, hippocampal synapses, and striatal synapses were evaluated. The half maximal inhibitory concentration (IC50) and bimolecular rate constant (K) of methomyl for AChE activity in different regions were calculated, and the type of inhibition of AChE activity by methomyl was determined.</p><p><b>RESULTS</b>AChE achieved the maximum activity at 370 °C, and the optimal time to determine initial reaction velocity was 0-17 min. There were dose- and time-response relationships between methomyl and AChE activity in the erythrocyte membrane and various brain areas. The IC50 value of methomyl for AChE activity in human erythrocyte membrane was higher than that in rat erythrocyte membrane, while the Ki value of methomyl for AChE activity in rat erythrocyte membrane was higher than that in human erythrocyte membrane. Among synapses in various brain areas, the striatum had the highest IC50 value, followed by the cerebellum, cerebral cortex, and hippocampus, while the cerebral cortex had the highest Ki value, followed by the hippocampus, striatum, and cerebellum. Lineweaver-Burk diagram demonstrated that with increasing concentration of methomyl, the maximum reaction velocity (Vmax) of AChE decreased, and the Michaelis constant (Km) remained the same.</p><p><b>CONCLUSION</b>Methomyl is a reversible non-competitive inhibitor of AChE. AChE of rat erythrocyte membrane is more sensitive to methomyl than that of human erythrocyte membrane; the cerebral cortical synapses have the most sensitive AChE to methomyl among synapses in various brain areas.</p>

An Outbreak of Food Borne Illness Due to Methomyl Pesticide Intoxication in Korea

On February 21, 2013, 6 elderly people collapsed abruptly after eating bean sprout bibimbab (boiled rice mixed with bean sprouts and seasoned with soybean sauce) at a countryside restaurant in the Chungbuk Province, Korea. Minutes after eating the meal, all of the patients lapsed into a state of stupor. Respiratory arrest developed in 2 patients; and one of two patients died of cardiac arrest. The autopsy identified methomyl and methanol in the deceased patient's gastric contents and in the remaining soybeanbean sauce seasoning. Five of the 6 patients ingested one spoonful of the soybeanbean sauce seasoning and survived, while one patient who died of cardiac arrest, ingested approximately two spoons. Symptoms of toxicity presented quickly in the subjects and progressed rapidly, including chest tightness, an unusual sensation in the pit of the stomach, dizziness, ataxia, and finally, collapse. Three patients who drank ethanol with the meal experienced only mild toxic symptoms. Our analysis of the clinical observations in these cases suggests that ingestion of methomyl pesticide and the additive toxicity of methanol may have been responsible for the intoxication.

Protective effect of grape seeds oil [Vitis Vinifera] on methomyl induced liver damage in albino rats

Liver damage was induced in adult male albino rats, weighting about 130-140 g, by oral administration of methomyl with single dose at two concentrations [1/10 or 1/20 LD[50]/day for short term [4 weeks] and long term [8 weeks]. The markers of liver damage were investigated by evaluating biochemical parameters in serum and liver tissues such as activities of aspartate aminotransferase [AST], alanine aminotransferase [ALT]], alkaline phosphatase [ALP], total bilirubin [TB], total protein [TP], total lipids [TL], total cholesterol [TC], triacylglycerols [TAG] and malondialdhyde [MDA] levels. In addition serum urea, creatinine and uric acid were assessed after 4 and 8 weeks. The effect of oral administration of grape seed oil [GSO] 4 ml/kg. Body weight/day on the above parameters for 4 and 8 weeks were investigated as a protective and antihepatotoxic effect. Oral administration of methomyl with single dose of concentration [1/10 or 1/20 LD[50]/day for 4 and 8 weeks, showed significant increase [p < 0.05] in serum liver enzymes activity [ALT, AST, ALP], TB, and MDA levels, while total protein showed a highly significant reduction as compared to negative control and control group received GSO, and the more effect was observed at the high dose of methomyl 1/lOLDso. ALT was not affected at the methomyl dose 1/20 LD[50]/day after 4 weeks. Serum lipid profile [TL, TC and TAG], creatinine and uric acid were also elevated in methomyl intoxicated rats with slight changes in TC and TL as compared to normal group at dose 1/20 LD[50]/day after 4 and 8 weeks. A significant - decrease [p < 0.05] and a high decrease [p < 0.01] in urea values were observed after short and long term in methomyl intoxicated rats. In liver tissues, elevation was found in ALP, TB, MDA, TC and TL levels after long term, while ALT, AST and total protein were significantly decreased, and intoxicated group treated with methomyl 1/10 LD[50] /day for 4 and 8 weeks was more acute effect as compared to control groups. Oral treatment with grape seed oil GSO 4 ml/kg body weight/day improved all the above parameters being almost similar to control values with treated low dose of methomyl

Degradation of methomyl by the novel bacterial strain Stenotrophomonas maltophilia M1 / Degradación del metomil por la nueva cepa bacteriana Stenotrophomonas maltophilia M1

The use of microorganisms in the degradation and detoxification of many toxic xenobiotics, especially pesticides, is an efficient tool for the decontamination of polluted sites in the environment. A novel bacterial strain (M1) was isolated from several water samples contaminated with methomyl which is capable of degrading methomyl pesticide (1000 ppm) in the presence of 0.05 percent glucose. These water samples were collected from different irrigation sites in Egypt where methomyl is heavily applied. The partial sequence of 16SrRNA gene of the isolate showed the highest similarity to Stenotrophomonas maltophilia. Restriction fragment patterns of isolated plasmid DNA showed that this strain harbours two different plasmids PMa (8Kb) and PMb (5Kb). PMb succeeded to be transferred to Escherichia coli DH5á strain. This transformed strain (M2) acquired the ability to grow in the presence of methomyl (1000 ppm) and 0.05 percent glucose. So it was deduced that the gene responsible for the degradation process was encoded by this plasmid. The ability of the two strains M1 and M2 to degrade methomyl was detected by using solid phased extraction coupled to capillary liquid chromatography-electrospray ionization-mass spectrometry (SPE-LC-ESI-MS).

Toxic effects of five insecticides and their mixture on male albino rats

Five insecticides namely; abamectin, carbosulfan, fenpropathrin, methomyl and profenofos were given by gavages to male albino rats. These insecticides were administered daily for 28 days with doses equaled 1/20 LD 50 either singly or in a mixture of all the insecticides together. The study revealed significant decreases in body and kidneys weights, while increases in liver weights in all the treatments. Most of the treatments induced significant elevations in serum alanine aminotransferase [ALT] and aspartate aminotransferase [AST], while caused decreases in acetylcholinesterase [AChE] activities. Fenpropathrin and the mixture induced significant increase in total protein content of the serum, while the other treatments induced significant decreases. Creatinine concentrations recorded significant elevations in fenpropathrin and methomyl treatments, while significant decrease in case of Profenofos. Degenerative changes and granularity of hepatocytes with Kupffer cells activation were observed in the treatments with the mixture or and methomyl. Shrinking in Bowman's capsule and degenerative changes of epithelium lining renal tubules were observed in rats treated with the mixture. Moreover, necrotic changes associated with desquamation of epithelium lining tubules were shown in rats treated with the mixture, fenpropathrin and methomyl. From the biochemical data, the joint action was estimated for the mixture composed of the five insecticides. The mixture interacts antagonistically with most of the measured biochemical parameters

Influence of parasitism by Chelonus insularis Cresson (Hymenoptera: Braconidae) on the susceptibility of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) to insecticides

The egg-larval parasitoid Chelonus insularis Cresson is a key parasitoid of the fall armyworm Spodoptera frugiperda (J. E. Smith) during the second field generation in the upper Magdalena River Basin, Colombia. In spite of selection pressure, the higher susceptibility of the second generation fall armyworm larvae to insecticides, compared with that of the first generation, suggests that the parasitism may be responsible for the apparent difference in susceptibility. Parasitized and non-parasitized 2nd-instar larvae of the fall armyworm were tested for susceptibility to chlorpyriphos, methomyl, cypermethrin, and Bacillus thuringiensis in the laboratory, using the leaf dip test. Parasitized larvae were up to 3.93 times more susceptible to chlorpyriphos, 3.71 times to methomyl, and 14.11 times to cypermethrin than non-parasitized larvae. The least effect of parasitism on susceptibility was found for B. thuringiensis. We discuss the negative influence of synthetic insecticide on the parasitoid population dynamics and its impact on insecticide resistance.

El parasitoide huevo-larva Chelonus insularis Cresson es un parasitoide clave del cogollero del maíz, Spodoptera frugiperda (J.E. Smith) durante la segunda generación de campo en el Valle Superior del Río Magdalena de Colombia. A pesar de la presión de selección se encuentra una susceptibilidad mayor a insecticidas en la segunda generación, comparado con la primera, siendo para esto la única diferencia aparente el parasitismo. Por esta razón, la susceptibilidad a clorpirifos, metomyl, cipermetrina y Bacillus thuringiensis de larvas parasitadas y no parasitadas del segundo instar del cogollero fueron evaluadas, utilizando el test de inmersión foliar. Las larvas parasitadas fueron 3,93 veces más suscptibles a clorpirifos, 3,71 veces más a metomyl y 14,11 veces más a cipermetrina que las no parasitadas. El menor efecto del parasitismo sobre la susceptibilidad se encontró con B. thuringiensis. Se discute la influencia negativa de las aplicaciones de insecticidas sintéticos sobre la dinámica poblacional del parasitoide, lo mismo que sus implicaciones en estudios de resistencia.

Monitoring of resistance to three insecticides on pepper weevil (Anthonomus eugenii) in populations from baja California Sur, México

Se determinaron los niveles de toxicidad en poblaciones de picudo del chile Anthonomus eugenii a tres insecticidas, carbaril, endosulfan y metomil. Las poblaciones de insectos fueron obtenidas a tres localidades en Baja California Sur, México: Benito Juárez (27º53'N 113º46'W), San José Viejo (23º07'N, 109º43'W) and San Juan de los Planes (23º58'N, 109º56'W). Las CL50 más elevadas corresponden al carbaril (178,4;635,4 y 5462,1 µgr/ml); endosulfan, tuvo valores intermedios (36,5; 34,1 y 47,1 µg/ml); mientras que los valores intermedios (36,5; 34,1 y 47,1 µg/ml); mientras que los valores más bajos correspondieron a metomil (1,3; 1,7 y 2,7 µg/ml), para Benito Juárez, San José Viejo y San Juan de los Planes respectivamente. Se puede concluir que las poblaciones de picudo del chile de San Juan de los Planes son resistentes a los tres insecticidas utilizados, teniendo mayor resistencia a carbaril, en comparación con las poblaciones provenientes de San José el Viejo y Benito Juárez. Los niveles susceptibilidad corresponden con las cantidades de insecticidas usados en contra del picudo del chile en las tres localidades de estudio y son una respuesta a la presión selectiva ejercida por esos compuestos

Stimulation single fiber electromyography in rats with myasthenia induced by organophosphorus insecticides and their mixtures poisoning / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the neuromuscular function and its relation with the occurrence of myasthenia in rats poisoned by dimethoate (D), phoxim (P), methomyl (M), M + D and M + P respectively.</p><p><b>METHODS</b>The stimulation single fiber electromyography(SSFEMG) at different stimulus frequencies(5, 10 and 20 Hz) was used. The whole blood cholinesterase (ChE) activity was measured 1 h before and after poisoning.</p><p><b>RESULTS</b>(1) Myasthenia occurred in 5 out of 9.5 out of 10.5 out of 5, and 8 rats poisoned by D, P, M + D, and M + P, respectively. (2) The average mean consecutive differences(MCD) at 5, 10, and 20 Hz in myasthenic rats were significantly higher than those of poisoned rats without myasthenia and the control ones. (3) SSFEMG changes at 5, 10 and 20 Hz were significantly consistent with the clinical manifestation of myasthenia, especially at 10 Hz and 20 Hz. (4) ChE activity was significantly lower in rats with P or D poisoning while ChE inhibition was of no difference in rats with M, M + D, and M + P poisoning. In the D poisoning and P poisoning groups, there was no significant difference in ChE inhibition between the rats with and without myasthenia.</p><p><b>CONCLUSION</b>Muscle weakness was associated with neuromuscular transmission dysfunction, but not well correlated with ChE inhibition. The SSFEMG with stimulus frequency at 10 Hz or 20 Hz could be used to detect the neuromuscular dysfunction during myasthenia induced by organophosphate insecticides and their mixtures poisoning.</p>

Children's plasma cholinesterase activity and fatal methomyl poisoning.

There is a case of a couple who intentionally killed their children with methomyl insecticide. This was presented as our initial investigation of plasma cholinesterase (ChE) activity in Thai children. A hundred and five healthy Thai children 5-6 years of age, participated in the project. Their plasma was drawn to measure ChE activity. Mean +/- standard deviation of the children ChE was 7,417 +/- 1,620 U/L. The enzyme activity of the children was not significantly different between gender and parents' occupations. However, the mean of female ChE activity appeared to be lower than male ChE. Children whose parents were farmers appeared to have lower ChE activity than those whose parents were employees, merchants, government officers, unemployed parents, or private business owners. Two victims of child homicide were presented with ChE activity approximately 6 and 9 per cent of the average, considering healthy children. It was concluded that children's plasma ChE activity lower than 10 per cent of normal, could be a lethal indicator of anti-ChE insecticide poisoning.

Comunicação entre mitocôndria e núcleo controla a transcrição do gene GAL1 de Saccharomyces cerevisae / Communication between mitochondrial and nuclear controls Saccharomyces cerevisiae GAL1 gene transcription

O gene nuclear GAL1 de Saccharomyces cerevisiae codifica uma galactoquinase induzida por galactose e reprimida por glicose. Três evidências indicam que a transcrição de GAL1 é dependente da atividade mitocondrial. Linhagens petite, com deleção no DNA da organela (pî) ou rompimento em gene nuclear, que codifica a farnesil transferase mitocondrial, são incapazes de induzir GAL1. Os inibidores de respiração antimicina-A e azoteto de sódio (NaN3), que atuam, respectivamente, nos complexos III e IV da cadeia de transporte de elétrons, impedem a indução de GAL1. Em células crescidas em glicose ou glicerol, o oligômero formado pela proteína URF13, na presença de metomil, produz um poro na membrana mitocondrial...

Clinical Observation of Anticholinesterase-inhibitor Insecticides Poisoning / 대한내과학회지

BACKGROUND: Organophosphate and carbamate insecticides have been used extensively in agriculture resulting in serious increases in poisoning. Levels of poisoning by carbamates and organic phosphorus compounds and the severity of associated symptoms are dependent not only on the degree of reduction of acetylcholinesterase activity in the nervous system but also on the rate of inhibition and the type of inhibitive action. The most striking differences between the clinical effects of the two groups of compounds are the much more rapid and spontaneous recovery from poisoning by carbamates and the relatively large difference between the smallest dosage of any carbamate that will cause mild illness and the lethal dosage of the same compound. The purpose of this study is to compare the clinical characteristics of acute intoxication by organophosphate and carbamate insecticides. METHOD: We retrospectively analyzed the clinical characteristics of 41 patients poisoned with organophsphates and 12 patients poisoned with carbamates, who were admitted to the department of internal medicine, Soonchunhyang Chunan hospital from January 1995 to December 1996. RESULTS: 1) The most common organophosphate was EPN (9 cases) followed by Dichlorvos (7 cases). In the carbamates group, Carbofuran (5 cases) was the most common followed by Methomyl (3 cases).2) The main cause of poisoning was ingestion for the purpose of suicide in both groups.3) The severity of poisoning was more acute in the organophosphate group than in the carbamate group.4) Altered consciousness and respiratory depression occurred more frequently in the organophosphate group than in the carbamate group. Six cases out of the organophosphate group suffered from respiratory depression 24 hours to 96 hours after poisoning.5) The activity of serum cholinesterase showed no significant difference between poisoning with organophosphates and with carbamates.6) The mortality rate was 22% in organophosphate intoxication and 16.7% in carbamate intoxication. The most common complication of organophosphate and carbamate intoxication was aspiration pneumonia. CONCLUSION: Carbamate insecticides exhibited less toxicity than organophosphates.

Clinical observation of Acute Carbamate Intoxication

We observed and analysed relating problems concerned to 21 patients of the acute carbamate intoxications, visited the emergency room of cheonju Presbyterian Medical center, from Oct 1993 to july 1996. The results were as follows : 1) Male was more prevalent than female with a ratio of 2:1 in sex distribution and the highest incidence of age group was in third decade and sixth decade of age in male sex 2) the most common drug of intoxication was deltanet in 7 cases, the remainders were bassa in 3 cases, b.p in 3 cases, huradan, qratel and methomyl in 2 cases, each, in order of frequency. 3)Among the exposed carbamate in 13 patients with respiratory failure, detanet was the most common in 6 cases, b.p in 3 cases, methomyl in 2 cases, bassa and huradan each in 1 case. 4) The serum ChE activity of patients were significantly reduced compare to normal.8 patients were between 20~50% of normal,8 patients were above 50% of normal, 4 patients were between 10~20% of normal, only 1 patient was below 10~20% of normal. 5) In 13 patients with respiratory failure, seam ChE activities were below 50% of normal. 6) In all patients with respiratory failure except 1 case time to recovery of the respiratory failure was below 48hrs. 7) Mean dose of atropine administered within first full atropinization and fist 24 hours was significantly higher in patients with than patients without respiratory failure in staitistics(29.3+/-23.3mg, 54.5+/-49.5mg VS 7.6+/-3.6mg, 13.6+/-6.9m) 8) 3 patients among a total of 21 patients expired. So that motality rate was 14.3%. Among the expired cases, 1 patients discontinued treatment due to economic problems and only 2 patients died in hospital during the treatment.