Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851341 (infestation)
 10,121 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adult, male rats were infected with 20 metacercariae of Fasciola hepatica given orally, other rats were left untreated. Five weeks after infestation, some animals received phenobarbitone, 3-methylcholanthrene, beta-naphthoflavone or Arochlor 1254, to induce liver drug metabolizing enzymes. Fascioliasis provoked decreases in aminopyrine N-demethylase, aniline hydroxylase, the mutagenic activity of cyclophosphamide and cytochrome P-450 concentration in untreated or phenobarbitone or Arochlor pretreated rats. In contrast, cytochrome b5, NADPH cytochrome c reductase, ethyoxycoumarin O-deethylase and the enzymatic activation of ethidium bromide were not affected by fascioliasis whatever pretreatment was given. Fascioliasis decreased liver drug metabolizing enzymes which were specifically induced by both phenobarbitone and Arochlor, this could be due to either the specific action of toxic excretions of flukes or to the particular localization of tissue damage within the liver lobule.
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PMID:Induction of drug metabolizing enzymes in the liver of rats infested with Fasciola hepatica. 286 51

The macrocyclic trichothecenes are a group of potent protein synthesis inhibitors that have been encountered in indoor air and food as a result of infestation by the fungus Stachybotrys. To evaluate the capacity of these mycotoxins to alter immune functions, the effects of satratoxin G, H, F, roridin A, and verrucarin A on interleukin 2 (IL-2) production and viability were evaluated in a murine T-cell model. EL-4 thymoma cells were stimulated with phorbol 12-myristate 13-acetate and ionomycin and concurrently exposed to various concentrations of the trichothecenes. Enzyme-linked immunosorbent assay (ELISA) of supernatants revealed that IL-2 concentrations at 24 and 72 h were significantly increased in cultures that were incubated in the presence of 0.5 to 1 ng/ml of satratoxin H, 1 to 5 ng/ml of isosatratoxin F, 0.1 to 0.5 ng/ml of roridin A, and 0.25 to 0.5 ng/ml of verrucarin A. However, IL-2 levels at these time points were significantly depressed when incubated in the presence of higher concentrations of satratoxin G (> or =2.5 ng/ml), satratoxin H and isosatratoxin F (> or =5 ng/ml), and roridin A and verrucarin A (> or =1 ng/ml). Cell viability, as measured by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, was depressed by each of the trichothecenes in a concentration-dependent manner. MTT responses were significantly decreased by as little as 0.5 ng/ml satratoxin G, roridin A, and verrucarin A and by 2.5 ng/ml of isosatratoxin F and satratoxin H. When these data were compared to those found in EL-4 cells for the 8-ketotrichothecene vomitoxin (deoxynivalenol), a common food contaminant, the macrocyclic trichothecenes were at least 100 times more potent. The results indicate that, at low concentrations, macrocyclic trichothecenes as a group could superinduce IL-2 production even while partially decreasing cell viability, whereas higher concentrations suppressed cytokine production and were markedly cytotoxic. The capacity of these compounds to dysregulate cytokine production in a biphasic fashion may play an etiologic role in outbreaks of human illnesses associated with indoor Stachybotrys contamination.
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PMID:Effects of satratoxins and other macrocyclic trichothecenes on IL-2 production and viability of EL-4 thymoma cells. 1049 15

In laboratory experiments toxicity of acetone, acrolein and carbon dioxide were investigated against 4 species of stored-product insects. In all experiments, acrolein was the most toxic compound to the tested insects. In empty-space trials, estimated LD50 values of acrolein for adults of Tribolium castaneum (Herbst) (Tenebrionidae), Rhizopertha dominica (F.) (Bostrychidae), Sitophilus oryzae L. (Curculionidae) and Oryzaephilus surinamensis L. (Silvanidae) were 7.26, 6.09, 6.37 and 5.65 microl L(-1), respectively. Penetration tests revealed that acetone and acrolein vapors could penetrate into the wheat mass and kill concealed insects in interkernel spaces. Comparison of LD50 values of acrolein between empty-space tests and penetration experiments indicated that the increase in penetration toxicity was 4.96, 4.54, 3.64 and 3.43-fold for T. castaneum, R. dominica, S. oryzae and O. surinamensis, respectively. The effect of carbon dioxide on the toxicity of acrolein and acetone was synergistic. In the hidden infestation trials, the acrolein vapors destroyed the developmental stages of S. oryzae concealed inside the wheat kernels and resulted in a complete control with concentration of 80 microl L(-1) for 24 h and subsequently observed during 8 weeks after the exposure. Wheat germination and plumule length was reduced following exposure to all doses of acrolein. Acetone and carbon dioxide were harmless to wheat seed viability. The mixture of carbon dioxide with acrolein can be considered as a potential fumigant for replacing methyl bromide or phosphine under ambient storage conditions specifically in empty-space fumigations.
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PMID:Studies on the toxicity of acetone, acrolein and carbon dioxide on stored-product insects and wheat seed. 1881 Sep 63

ABSTRACT Sudden death syndrome (SDS) of soybean is caused by the soilborne Fusarium solani f. sp. glycines (synonym F. virguliforme). In a sequential approach, two multifactor factorial-design microplot experiments were conducted to investigate the effects of fungal infestation levels and soil moisture on both root necrosis and foliar SDS severity, and the interaction between F. solani f. sp. glycines and Heterodera glycines in fumigated versus nonfumigated soil. In 2003, soybean cv. Spencer was grown in nonfumigated or methyl bromide-fumigated soil and infested with increasing levels of F. solani f. sp. glycines, either under rainfall or irrigated after growth stage V6/R1. In 2004, interactions between F. solani f. sp. glycines and H. glycines were explored in a factorial inoculation design in fumigated or nonfumigated soil, planted to Williams 82 or Cyst-X20-18. In both years, higher levels of foliar SDS severity and root necrosis were found in F. solani f. sp. glycines-infested soils with H. glycines than in soils without the nematode on the soybean cultivars susceptible to both pathogens. Both natural infestations of H. glycines in 2003 and artificially amended populations of H. glycines in 2004 contributed to higher foliar SDS severity. More severe foliar SDS symptoms always were associated with more root necrosis, but elevated levels of root necrosis did not predict severe leaf symptoms. In contrast to the critical role of H. glycines, increasing fungal infestation levels had no significant effects on increasing either foliar SDS symptoms or root necrosis. Effects of moisture regime and fungal infestation levels also were examined in factorial greenhouse and growth chamber experiments. High soil moisture resulted in higher levels of SDS root necrosis. In the greenhouse, root necrosis increased at a higher rate in low soil moisture than the rate in high soil moisture. The two pathogens acted as a complex and the disease development was strongly dependent on high soil moisture.
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PMID:Interaction of Fusarium solani f. sp. glycines and Heterodera glycines in Sudden Death Syndrome of Soybean. 1894 50

ABSTRACT Two field experiments were conducted to study the effects of added nitrogen, calcium, and indoleacetic acid, in the presence or absence of ring nematodes (Mesocriconema xenoplax), on susceptibility of peach to bacterial canker. When noninfested soil was inoculated with ring nematodes, peach tree susceptibility to bacterial canker infection caused by Pseudomonas syringae pv. syringae was dramatically increased after a period of 2 years. However, no evidence was found that ring nematode infestation increased tree water stress or, in turn, altered plant calcium uptake. Soil fumigation with methyl bromide prior to planting in a commercial orchard significantly reduced both nematode populations and peach tree susceptibility to bacterial canker infection when compared with nonfumigated treatments. In both experiments, tree susceptibility, as measured by canker length following inoculation of stems with P. syringae pv. syringae, was negatively correlated with plant tissue nitrogen content and positively correlated with tissue calcium content. A principal components analysis showed that tissue nitrogen and calcium levels were negatively correlated, and that high-nitrogen, low-calcium tissues were less susceptible to bacterial canker than low-nitrogen, high-calcium tissues. These results indicate that the increased susceptibility of peach to P. syringae pv. syringae under nematode infestation conditions is mediated by both nutritional effects (primarily nitrogen) and nutritional-independent effects, but do not support previous reports of beneficial effects of calcium for reducing bacterial canker.
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PMID:Influence of Ring Nematode Infestation and Calcium, Nitrogen, and Indoleacetic Acid Applications on Peach Susceptibility to Pseudomonas syringae pv. syringae. 1894 78

Meloidogyne incognita (Mi) and Rotylenchulus reniformis (Rr) interactions on sweet potato were studied in naturally and artificially infested field plots for 3 years. In a naturally infested field, early season counts of Mi or Rr were positively correlated with later counts of the same nematode, but negative correlations were found between early Mi and subsequent Rr, and early Rr and subsequent Mi counts. In field plots fumigated with methyl bromide and then infested with low levels of Rr, Mi, and Rr + Mi, final population densities of Mi juveniles were reduced by Rr, but Rr was not affected by Mi. In field plots with a high natural population density of Rr, artificial infestation with high levels of Mi in both fumigated and nonfumigated treatments inhibited Rr, while the final Mi juvenile population density was not affected. Results indicate that a competitive interaction exists with each species capable of inhibiting the other and becoming the dominant population. The nematodes had no apparent effect on yield at the inoculum densities used, either alone or mixed. Both nematodes increased cracking of sweet potatoes, but mixed populations did not differ in incidence of cracking from either Rr or Mi alone.
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PMID:Population Dynamics of Meloidogyne incognita and Rotylenchulus reniformis Alone and in Combination, and Their Effects on Sweet Potato. 1929 92

Carposina niponensis Matsumura (Lepidoptera: Carposinadae), is widely distributed in pome fruit production areas in China and presents a problem in some export markets because it is considered a quarantine pest by some countries. Methyl bromide is the only fumigant used for fumigation of apples (Malus spp.) for export. However, phosphine is a candidate replacement that can be applied directly at low temperature. Here, laboratory tests showed that tolerance of different stages of C. niponensis to phosphine fumigation at 0 degrees C differed greatly; first-second-instar larvae were the least tolerant stage and the mature fifth instars were the most tolerant stage. In the mature larvae, fumigation tests, with a range of phosphine concentrations from 0.42 to 1.95 mg/liters and exposure periods of 24 h to 14 d at 0 degrees C indicated narcosis when phosphine concentration was > or = 1.67 mg/liter and that a 15.52-8.14-d fumigation period was required to achieve 99% mortality with different phosphine concentrations. The expression of C(0.7)T = k was obtained, which indicated that exposure time was much more important than concentration of phosphine in mortality of mature larvae of C. niponensis. All results suggested that phosphine fumigation at low temperature offers promising control of C. niponensis infestation in pome fruit.
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PMID:Toxicity of phosphine to Carposina niponensis (Lepidoptera: Carposinadae) at low temperature. 2130 17

Methyl bromide fumigation is widely used as a phytosanitary treatment. Mexican fruit fly, Anastrepha ludens (Loew) (Diptera: Tephritidae), is a quarantine pest of several fruit, including citrus (Citrus spp.), exported from Texas, Mexico, and Central America. Recently, live larvae have been found with supposedly correctly fumigated citrus fruit. This research investigates the efficacy of the previously approved U.S. Department of Agriculture-Animal and Plant Health Inspection Service treatment schedule: 40 g/m3 methyl bromide at 21-29.4 degrees C for 2 h. Tolerance ofA. ludens to methyl bromide in descending order when fumigated in grapefruit (Citrus X paradisi Macfad.) is third instar > second instar > first instar > egg. Two infestation techniques were compared: insertion into fruit of third instars reared in diet and oviposition by adult A. ludens into fruit and development to the third instar. Inserted larvae were statistically more likely to survive fumigation than oviposited larvae. When fruit were held at ambient temperature, 0.23 +/- 0.12% of larvae were still observed to be moving 4 d postfumigation. Temperatures between 21.9 and 27.2 degrees C were positively related to efficacy measured as larvae moving 24 h after fumigation, pupariation, and adult emergence. Coating grapefruit with Pearl Lustr 2-3 h before fumigation did not significantly affect the proportion of third instars moving 24 h after fumigation, pupariating, or emerging as adults. In conclusion, fumigation with 40 g/m3 methyl bromide for 2 h at fruit temperatures >26.7 degrees C is not found to be inefficacious for A. ludens. Although a few larvae may be found moving >24 h postfumigation, they do not pupariate.
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PMID:Evaluation of the efficacy of the methyl bromide fumigation schedule against Mexican fruit fly (Diptera: Tephritidae) in citrus fruit. 2140 40

The fumigation of freight containers to protect transported goods from fungal and pest infestation has increased worldwide in the last five years due to international regulations requiring fumigation or heat treatment of wooden packaging material and dunnage. We have found in 2008 that every sixth container and its contents do retain harmful concentrations of various fumigants and chemicals, representing a significant health risk for port and transport workers, customs officials, warehousemen, store employees and consumers. The shipping documents of these containers did not provide any information about the fumigation procedure or the used fumigant. We report here the cases of 26 patients introduced to our outpatient clinic with presumed intoxication to fumigants, or with symptoms due to inhaling the air out of fumigated containers. All patients were examined from 2007 to 2010 according to a standardized comprehensive diagnostic program. We were able to confirm the diagnosis based on typical symptoms and extensive clinical examination; by laboratory analysis we identified ethylene dichloride, methyl bromide, phosphine and methylene chloride. The predominant symptoms were headaches, concentration and memory problems, dizziness and nausea, irritation of the skin and mucous membranes and a reduced ability to do exercise. In addition to the neurological and neuropsychological impairments our analyses verified the development of reactive airways dysfunction syndrome (RADS) in 14 of 26 patients with long lasting symptoms due to their contact with fumigants. Intoxications with fumigants are serious and could be avoided. These systematical explored cases show the sustainable impact for health and socio-economic wellbeing. These findings also emphasize the necessity for international standards on permitted fumigants, appropriate labeling in the shipping documents and handling of fumigated containers.
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PMID:Surprises perilous: toxic health hazards for employees unloading fumigated shipping containers. 2163 9

Grain legumes are an important source of proteins in vegetarian diet besides their role in biological nitrogen fixation. They are prone to heavy pest infestation both on and off the field. Pest associated losses are an important contributing factor towards declining per capita availability of grain legumes. Synthetic chemical pesticides have played an important role in crop preservation, however their incessant use has posed several environmental and human health concerns. Methyl bromide and phosphine are commonly used for the post harvest preservation of grain legumes. However, the former has to be phased out by 2015 as per the Montreal protocol whereas the latter is showing development of resistance to it by the insects. In the light of this, alternative, safer and sustainable strategies are needed for crop protection. Plants can serve as a rich source of bioactive chemicals for this purpose. Both primary as well as secondary metabolites can be evaluated against the target pests. The paper reviews the status of research in the area of use of plant metabolites in post harvest pest management of grain legumes.
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PMID:Plant metabolites: an alternative and sustainable approach towards post harvest pest management in pulses. 2357 29


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