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1.
Maria Do Carmo Antunes-Madeira Leonor M. Almeida Vitor M. C. Madeira 《Pest management science》1991,33(3):347-357
The effects of DDT (0-100 μM) in pure phospholipid and phospholipid/cholesterol bilayers were investigated by fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH), a probe located in the bilayer interior, and by excimer to monomer fluorescence intensity ratio (I′/I) of 1,3-di(l-pyrenyl)propane (Py(3)Py), a probe sitting closer to the polar region. In the gel phase of dimyristoylphosphatidylcholine (DMPC) bilayers, DDT induces concentration-dependent fluidizing effects into the hydrophobic membrane regions, but no effects are observed in the outer regions of the membrane, as evaluated by DPH and Py(3)Py, respectively. Furthermore, in the fluid phase of DMPC and for DDT concentrations higher than 10 μM, I′/I of Py(3)Py decreases, reflecting an order increase of the probe environment and DPH fails to detect any apparent effect. Similar effects were observed in other pure lipid bilayers, namely dipalmitoylphosphatidylcholine (DPPC) and distearoylphosphatidylcholine (DSPC). Unlike DPH, Py(3)Py is very sensitive to DPPC and DSPC pre-transitions which are not abolished by 50 μM DDT. This DDT concentration inhibits to some extent the cholesterol-induced ordering in DMPC bilayers and high cholesterol concentrations (? 30 mol%) do not prevent insecticide interaction, as evaluated by DPH. On the other hand, the effects of DDT reported by Py(3)Py depend on temperature and cholesterol content of DMPC bilayers. Thus, for cholesterol levels ranging from 10 to 50 mol% and for temperatures below the phase transition temperature of DMPC, Py(3)Py fails to detect any significant effect. Nevertheless, above the phase transition temperature of DMPC, Py(3)Py detects either ordering effects of DDT at low cholesterol contents (< 20 mol%) or fluidizing DDT effects at high cholesterol levels (> 20 mol%). 相似文献
2.
The organophosphorus insecticides, parathion and azinphos (10?5-10?4M), significantly stimulate the Ca2+-pump activity of sarcoplasmic reticulum, while malathion has a limited effect. The rates of Ca2+ translocation and ATP hydrolysis are both stimulated and, apparently, the ratio is improved. Parathion and azinphos maximally increase this ratio by 26 and 14%, respectively. The organochlorine compounds, DDT and aldrin, also stimulate the Ca2+ pump, and lindane has a reduced effect. These effects are smaller than those observed for parathion and azinphos. The order of effectiveness is similar to the toxicity of the compounds to mammals and can be described as follows: parathion > azinphos > DDT ≈ aldrin > malathion ≈ lindane. 相似文献
3.
M.C. Antunes-Madeira A.P. Carvalho Vítor M.C. Madeira 《Pesticide biochemistry and physiology》1980,14(2):161-169
The organophosphorus insecticides, parathion and azinphos, significantly lower the midpoint temperature of thermotropic phase transitions of lipid bilayers, but malathion has no effect. The effects of parathion and azinphos are more pronounced on bilayers of short-chain lipids. These compounds induce phase separations in binary lipid mixtures containing dimyristoyl and distearoyl phosphatidylcholines, although similar effects could not be noticed in mixtures of dimyristoyl phosphatidylcholine and dimyristoyl phosphatidylethanolamine. Furthermore, the compounds partially restore phase transitions abolished by cholesterol. It is concluded that parathion and azinphos induce molecular disorders in lipid bilayers, either by having fluidizing effects or by promoting phase separations as a consequence of preferential interaction with more fluid lipids. The interaction of the compounds with cholesterol-containing bilayers produces phospholipid-rich lateral domains. 相似文献
4.
M.C. Antunes-Madeira A.P. Carvalho Vitor M.C. Madeira 《Pesticide biochemistry and physiology》1981,15(1):79-89
Insecticides exert antilytic effects on pig erythrocytes by preventing osmotic disruption of membranes in critical hypotonic saline media. The order of effectiveness is the following: lindane > aldrin ≈ azinphos > parathion ≈ DDT > malathion; empirical protective indexes estimated for K+ leakage, at 0.09 M NaCl, were 5.6, 3.9, 2.9, 2.8, and 2.0, respectively. Erythrocytes swell and hemolyze in solutions containing glycerol below 0.6 M. At higher concentrations and temperatures below 20°C, the extent of cell lysis is very limited and virtually nil in 1 M glycerol. In hypertonic glycerol solutions, cells swell until the initial equilibrium volume is reached and, then, the swelling process ceases. Swelling in 1 M glycerol is related to its permeation through hydrophobic membrane domains. The activation energies of permeation are similar to the dehydration energies of glycerol molecules. As the temperature is increased above 20°C, erythrocytes undergo lysis. The organophosphorus insecticides, parathion and azinphos (10?4M), significantly increase the swelling rates and the extent of cell lysis. Malathion and chlorinated insecticides do not exert apparent effects. However, these compounds are effective in liposomes reconstituted with lipids extracted from erythrocyte membranes. 相似文献
5.
Many insecticides (e.g. DDT, lindane, pyrethroids) are hydrophobic molecules which bind extensively to biological membranes. Binding of insecticides to phospholipid bilayers frequently shows saturation, with binding increasing with increasing insecticide concentration up to some limit, beyond which no further insecticide is incorporated into the bilayer. For lindane, this limit has been shown to correspond to the concentration at which the aqueous phase becomes saturated. Simple alkanes show similar saturation phenomena, and binding of halogenated alkanes can be followed by fluorescence quenching methods. It is shown that effects of hydrophobic molecules on bilayer fluidity are small. Effects of alkanes and insecticides on the activity of the (Ca2+-Mg2+)-ATPase purified from sarcoplasmic reticulum follow from direct binding to the ATPase, at sites which are not at the lipid-protein interface of the ATPase. 相似文献
6.
Resistance and cross-resistance to insecticides in human head lice from Florida and California 总被引：1，自引：0，他引：1
Kyong Sup Yoon Jian-Rong Gao Si Hyeock Lee Gerald C. Coles Terri L. Meinking David Taplin John D. Edman MiwaKo Takano-Lee J. Marshall Clark 《Pesticide biochemistry and physiology》2004,80(3):192-201
Head lice from Florida (SF-HL) and California (SC-HL) were resistant to permethrin compared with colonized susceptible lice from Panama (PA-HL) (5.5- and 3.4-fold, respectively) and Ecuador (EC-HL) (8.5- and 5.3-fold, respectively). Permethrin-resistant lice were cross-resistant to pyrethrum and DDT. DNA sequencing validated presence of kdr-type mutations (T929I and L932F). Permethrin resistance was synergized by piperonyl butoxide (PBO) in SC-HL. Resistance to malathion in SF-HL (1.4–2.2-fold) and SC-HL (2.1–3.6-fold) was detected. Malathion resistance in SF-HL was synergized by S,S,S-tributylphosphorotrithioate (DEF) and by PBO in SC-HL. Malathion/permethrin-resistant lice from the UK (BR-HL) were synergized by DEF but not synerziged by PBO. PBO protected BR-HL from malathion, indicating suppressed desulfuration. Abamectin resistance in SF-HL (1.7–2.5-fold) and SC-HL (1.8–2.3-fold) was detected. No resistance to lindane was found. Thus, multiple resistance mechanisms against commonly available and widely used pediculicides and insecticides are apparently occurring. 相似文献
7.
Houseflies were pretreated with olive oil by two methods, topical application or injection, then exposed to residues of DDT, dieldrin, methyl parathion, or dimethoate. Knockdown was recorded for normal and pretreated flies. Knockdown rates of pretreated flies were significantly different (generally lower) from normal flies in practically all cases. Protection against knockdown was positively correlated with olive oil-water partition coefficients of the insecticides. The effect of dosage on the degree of protection was investigated with DDT. These data support the possibility that hemolymph distributes insecticides throughout the body in exposed insects. 相似文献
8.
The toxicity of DDT and malathion to the larvae of Mamestra brassicae was determined following several methods of application. The toxicity (LD50), expressed as μg insecticide per g of insect, did not change significantly between larval instars (a) when either insecticide was injected into fourth to sixth instars; (b) when DDT was applied in the food of fifth and sixth instars; or (c) when malathion was applied topically to second to sixth instars. Significant changes in toxicity were found between successive instars when DDT was applied topically, but there was no clear trend. When malathion was applied in the food, the fifth instars were more susceptible than the sixth instars; it was found that the former consumed a toxic dose of malathion at a greater rate, and that probably malathion was degraded in the gut at a slower rate. In a contact test, the first to third instars were far more susceptible than the later instars to malathion; with DDT this trend was much less marked. Uptake studies with [14C]malathion showed that differences in the contact toxicity of malathion between instars could be explained, at least partly, by the decline in uptake per unit weight with increasing larval size. 相似文献
9.
The effect of DDT and several analogs upon bilayer membranes was studied, using the fluorescent dye di (octadecyl)oxycarbocyanin as a probe. It was shown in flat bilayers of Torpedo electroplax phospholipids, using fluorescence correlation spectroscopy, that neither DDT nor its physiologically inactive analog, p,p′-hydroxy-DDT, affected the fluidity of the membrane. However DDT, and not the analog, displaced half of the dye from the membrane. In studies with lecithin or Torpedo electroplax phospholipid vesicles, using simple fluorescence measurements, no displacement of the dye was observed by DDT or its analogs. 相似文献
10.
A study of the metabolism of 14C-labeled dieldrin, DDT, malathion, and carbaryl during penetration of the isolated midgut of two insects (Blaberus discoidalis and Manduca sexta) and a section of the intestine of a mammal (Mus musculus) is reported. There was appreciable metabolism of malathion during penetration, including differences in the activation reaction to malaoxon, between insects and mammals. Metabolism was relatively slow during penetration of carbaryl and the chlorinated hydrocarbon insecticides, and little difference in metabolic patterns was noted among the three species. The penetration studies were supported by experiments in which insecticides were incubated with intact and homogenized midgut preparations. 相似文献
11.
Twenty-seven insecticides, including organochlorine, organophosphorus compounds and carbamates were tried for potentiation of the toxic effect of malathion. Carbaryl, diazinon, fenthion, gamma-BHC, parathion and tetrachlorvinphos potentiated the action of malathion. Fourteen insecticides gave additive effects while seven proved antagonistic. Insecticides which showed potentiation, were further tested by mixing with malathion in the ratios of 1:9, 3:7, 5:5, 7:3 and 9:1. All the five combinations in the six mixtures gave potentiating effects. Maximum potentiation of 17.6 times was observed in 1:9 combination of malathion and gamma-BHC. The proportions in which the insecticides were mixed had a pronounced effect on the toxic effect of malathion. 相似文献
12.
J. A. J. Veenenbos 《European journal of plant pathology / European Foundation for Plant Pathology》1953,59(2):35-50
Samenvatting Gedurende de laatste twee jaren werden door de P.D. een aantal bestrijdings-proeven genomen tegen enkele koolzaadinsecten.Tegen de koolzaadaardvlo (Psylliodes chrysocephala L.) bleken twee, of nog beter drie behandelingen met DDT (500 g technisch DDT/ha) beter te voldoen dan een even groot aantal behandelingen met parathion (250 g technisch parathion/ha). Het effect van drie behandelingen met HCH (65 g gamma/ha) bleef bij dat van beide bovengenoemde middelen sterk ten achter.Is de bestrijding van de aardvlooien zelf, welke dus bij voorkeur met DDT dient te geschieden, niet geslaagd of om bepaalde redenen niet mogelijk geweest, dan moet de bestrijding zich richten tegen de larven in de bladstelen, waarvoor parathion in aanmerking komt.Bij de bestrijding van de koolzaadsnuitkever (Ceuthorrhynchus assimilis
Payk.) werden gunstige resultaten bereikt met een middel, dat zowel HCH als dieldrin bevat. HCH (400 g gamma/ha) en toxapheen (1500 g chloorcampheen/ha) gaven een iets minder goede werking te zien, terwijl de werking van parathion (250 g technisch parathion/ha) slechter was dan van alle bovengenoemde middelen.De bestrijding van de galmuglarven (Dasyneura brassicae
Winn.) in de hauwen door middel van twee behandelingen met parathion (250 g technisch parathion/ha) leidde niet tot het gewenste resultaat.Vangpalen zullen vermoedelijk nuttige gegevens kunnen verstrekken over het moment waarop en de richting waaruit de snuitkevers komen aanvliegen.Een schatting van de kosten en de baten van de bestrijding der koolzaadsnuitkever maakt het zeer waarschijnlijk dat deze bestrijding economisch verantwoord is, indien veel kevers in het gewas aanwezig zijn.Summary During the past two years the Plant Protection Service has carried out experiments on the control of certain insect pests of colza.Two or preferably three treatments with DDT (500 g/ha technical DDT) against the cabbage stem flea beetle (Psylliodes chrysocephala L.) proved to be more satisfactory than the same number of treatments with parathion (250 g/ha technical parathion). The results of three treatments with BHC (65 g/ha gamma isomer BHC) were much behind those of the above mentioned chemicals.If control of flea beetles, which should normally take place with DDT, should fail or for any reason could not be carried out, control of the larvae in the leaf stalks can be obtained with parathion.Control of gall-midge larvae (Dasyneura brassicae
Winn.) in the pods by two treatments with parathion (250 g/ha technical parathion) was not satisfactory.Effective control of cabbage seed weevil (Ceuthorrhynchus assimilis
Payk.), was obtained with a formulation containing both BHC and dieldrin. The results with BHC (400 g/ha gamma isomer) and toxaphene (1500 g/ha chlorocamphene) were not quite as good; parathion (250 g/ha technical parathion) was less effective than all the above-mentioned chemicals.Some useful information about the time of arrival of weevils and the direction from which they come can probably be got from the use of sticky board traps.An estimate on the expenses incurred in the control of cabbageweevil and of the advantages to be expected, makes it probable that, in a heavily infected crop, control is economically justified. 相似文献
13.
BACKGROUND: To evaluate the insecticide susceptibility status of Aedes aegypti (L.) in Colombia, and as part of the National Network of Insecticide Resistance Surveillance, 12 mosquito populations were assessed for resistance to pyrethroids, organophosphates and DDT. Bioassays were performed using WHO and CDC methodologies. The underlying resistance mechanisms were investigated through biochemical assays and RT‐PCR. RESULTS: All mosquito populations were susceptible to malathion, deltamethrin and cyfluthrin, and highly resistant to DDT and etofenprox. Resistance to lambda‐cyhalothrin, permethrin and fenitrothion ranged from moderate to high in some populations from Chocó and Putumayo states. In Antioquia state, the Santa Fe population was resistant to fenitrothion. Biochemical assays showed high levels of both cytochrome P450 monooxygenases (CYP) and non‐specific esterases (NSE) in some of the fenitrothion‐ and pyrethroid‐resistant populations. All populations showed high levels of glutathione‐S‐transferase (GST) activity. GSTe2 gene was found overexpressed in DDT‐resistant populations compared with Rockefeller susceptible strain. CONCLUSIONS: Differences in insecticide resistance status were observed between insecticides and localities. Although the biochemical assay results suggest that CYP and NSE could play an important role in the pyrethroid and fenitrothion resistance detected, other mechanisms remain to be investigated, including knockdown resistance. Resistance to DDT was high in all populations, and GST activity is probably the main enzymatic mechanism associated with this resistance. The results of this study provide baseline data on insecticide resistance in Colombian A. aegypti populations, and will allow comparison of changes in susceptibility status in this vector over time. Copyright © 2011 Society of Chemical Industry 相似文献
14.
The effect of DDT, 11 analogs, dieldrin, and lindane was studied on the pressure-area curves obtained by compressing monolayers of lecithin. The minimum cross-sectional area of lecithin and the compounds was measured by photography of models. All compounds shifted the pressure area curves in a direction and to an amount that suggested they formed 1:1 complexes with lecithin, and the complex had the cross-sectional area of the compound. DDT did not complex with cholesterol monolayers. Both DDT and DDMU formed complexes with phospholipids from Torpedo electroplax which resembled those with lecithin. The lack of difference in effects on monolayers between physiologically active and inactive analogs indicated that the monolayer effects did not explain the physiological action of DDT. 相似文献
15.
Effect of several insecticides on pomegranate aphid,Aphis punicae (Passerini) (Homoptera: Aphididae) and its predators under field conditions 
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下载免费PDF全文 A. A. Abd‐Ella 《EPPO Bulletin》2015,45(1):90-98
The pomegranate aphid, Aphis punicae (Passerini) (Homoptera: Aphididae) is one of the most important pests in Egypt on pomegranate trees. The study presented in this paper was conducted from 2012 to 2013 to compare the efficiency and selectivity of neonicotinoids (acetamiprid, imidacloprid, thiamethoxam and dinotefuran), organophosphate (malathion) and carbamate (pirimicarb) insecticides against pomegranate aphid and the associated predators, Coccinella undecimpunctata Linnaeus, Chrysoperla carnea (Stephens) and Syrphus corolla Fabricius. These insecticides significantly reduced the pomegranate aphid population by an average of between 70.6 and 90.7%. The effects persisted for up to 15 days after the end of treatment. The greatest control of A. punicae was achieved by thiamethoxam > acetamiprid > imidacloprid > pirimicarb > dinotefuran > malathion. Acetamiprid, imidacloprid, thiamethoxam, malathion and pirimicarb were harmful to predators and the observed reduction ranged from 75.4 to 100% and dinotefuran was moderately harmful to lacewings with an average reduction about 64.4%. These results suggested that the neonicotinoid insecticides can be considered as promising candidates for controlling the pomegranate aphid as, although they do have harmful to moderately harmful effects on predators, they are significantly less toxic to these beneficial organisms than malathion and pirimicarb. 相似文献
16.
The effects of aldrin, carbaryl, α- and γ-chlordane, dichlorodiphenyldichloroethane (DDD), dichlorodiphenyltrichloroethane (DDT), dieldrin, endrin, heptachlor, lindane, methoxychlor, and nonachlor on the short-circuit current and resistance of the isolated intact frog skin were studied. The short-circuit current is approximately equivalent to the rate of active transport of sodium, while the resistance indicates the summed ionic permeability of the skin. At a concentration of 2 × 10?4M, only carbaryl, DDD, dieldrin, and lindane produced significant (P<0.05, paired t test) changes in the short-circuit current. Nonachlor produced a decrease (P=0.12) in the short-circuit current and also increased the resistance (P=0.07). DDD, dieldrin, and carbaryl caused significant increases in short-circuit current while at the same time the resistance was significantly decreased. Lindane increased both the short-circuit current and the resistance. It was concluded that the frog skin probably contains effective permeability barriers that prevent externally applied insecticides from reaching the site of active sodium transport. It appeared likely that most of the insecticides produced the observed effects on the frog skin by altering the sodium permeability of the outer barrier. 相似文献
17.
The prolonged use of dimethoate, introduced into Denmark to control houseflies (Musca domestica L.) that had become resistant to parathion and diazinon, resulted ultimately in dimethoate resistance. Selection with dimethoate led to the disappearance of the hydrolytic phosphatase, a major mechanism of resistance to parathion and diazinon, and its replacement by the acetylcholinesterase AChER with somewhat decreased sensitivity to inhibition by organophosphorus (OP) insecticides. The hydrolytic phosphatase probably disappeared because low substrate turn-over made it ineffective against dimethoxon (O, O-dimethyl S-methylcarbamoylmethyl phosphorothioate, also known as omethoate). which accumulates at higher concentrations than paraoxon (diethyl4-nitrophenyl phosphate) in the haemolymph. Dimethoate selected AChER preferentially because it improved the chances of houseflies surviving against the relatively poor AChE inhibitor dimethoxon, whereas its relatively small insensitivity to OP insecticides, unimportant against good inhibitors such as paraoxon, prevented its selection by parathion. 相似文献
18.
Field efficacy of five insecticides to a greenhouse strain ofFrankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) of known resistance status was studied. In a greenhouse trial, the mortality of aF. occidentalis strain (Uncali) which exhibited resistance only against cypermethrin in laboratory assays, reached 56%, 68%, 82%, 94% and
99%, 24 h after application of abamectin, cypermethrin, endosulfan, malathion and methomyl, respectively. In the laboratory,
for larval mortality equal to that achieved in the field, much lower doses — half of the field dose of cypermethrin and endosulfan,
and one-third and one-sixth of malathion and methomyl, respectively, were required in topical application. Because of differences
between laboratory and field responses ofF. occidentalis to insecticides, a sound resistance evaluation program to determine field efficacy of insecticides is needed. Resistance
increased 28.0- and 139.3-fold at LC50 in theF. occidentalis strain subjected to 27 and 44 cycles of cypermethrin selection, respectively. A slight cross-resistance of two- to threefold
was found with endosulfan, malathion and methomyl and no cross-resistance was observed with abamectin.
http://www.phytoparasitica.org posting August 4, 2008. 相似文献
19.
Melissa C. Hardstone 《Pesticide biochemistry and physiology》2006,84(3):236-242
Cytochrome P450-dependent monooxygenases are important in the activation and detoxification of numerous insecticides. In this study, a Drosophila melanogaster Cyp6d4 null mutant was used to determine the role of this P450 in insecticide metabolism. This null mutant was generated by imprecise excision of a mobile P element located upstream to the P450 gene Cyp6d4. Comparative analysis between the non-functional mutant and relevant control strains shows that Cyp6d4 does not appear to be involved in the metabolism of chlorfenapyr, cypermethrin, diazinon, imidacloprid, malathion, oxamyl, parathion, or pyrethrum extract, even though these insecticides are known to be activated or detoxified by P450-monooxygenases. No obvious abnormalities in development were seen in the Cyp6d4 null mutant, indicating that Cyp6d4 is not critical for the metabolism of vital endogenous substrates. 相似文献
20.
Studies of the uptake of dieldrin, lindane, and DDT by isolated rat hepatocytes in Krebs-Henseleit salt solution containing 2.34% bovine serum albumin have shown that the partition equilibrium of these hydrophobic organochlorine compounds is established very rapidly between the hepatocytes and the extracellular medium by reversible uptake and release processes. In the hepatocyte suspension system, these compounds are in dynamic partition equilibrium between the hepatocytes and the Krebs-Henseleit salt solution, and also between the bovine serum albumin molecules and the solution. The respective rate constants for the uptake and release processes were 0.83 and 2.52 × 10?2 sec?1 in a 2-ml suspension containing 106 cells. It has thus been demonstrated that the transport of hydrophobic organochlorine compounds between the hepatocytes and the extracellular medium is a much faster process than the metabolic transformation reaction in hepatocytes. 相似文献