Organophosphorus resistance in the sheep blowfly, Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae): a genetic study incorporating synergists

1982 ◽  
Vol 72 (4) ◽  
pp. 573-582 ◽  
Author(s):  
P. B. Hughes
Keyword(s):  
Organophosphorus Compounds ◽  
Dominant Gene ◽  
Piperonyl Butoxide ◽  
Lucilia Cuprina ◽  
Chromosome 4 ◽  
Organophosphorus Insecticides ◽  
Resistance Factors ◽  
Nitrophenyl Phosphate ◽  
Pre Treatment ◽  
Esterase Inhibitor

AbstractPre-treatment of females of Lucilia cuprina (Wied.) with the synergist piperonyl butoxide increased the resistance factors of an organophosphorus-resistant strain Q to four organophosphates in comparison to the susceptible strain LS. However, pre-treatment with S,S,S-tributylphosphorothrithioate (TBPT) reduced the resistance factors of Q to three organophosphorus insecticides. As TBPT is an esterase inhibitor, it is suggested that esterases contribute to resistance in the Q strain. Resistance to diazinon in the Q strain is due to a single, partially-dominant gene on chromosome 4. By the use of the backcross and discriminating dose technique, resistance to parathion, fenitrothion, chlorfenvinphos and fenitro-oxon (dimethyl 3-methyl-4-nitrophenyl phosphate) (the latter two were synergised by piperonyl butoxide to obtain a genetically discriminating dose) was also shown to be controlled by a single, partially-dominant gene on chromosome 4. It is concluded that this gene confers resistance to organophosphorus compounds in L. cuprina, probably by providing an esterase with enhanced ability to degrade organophosphates.

Effect of piperonyl butoxide on diazinon resistance in field strains of the sheep blowfly, Lucilia cuprina (Diptera: Calliphoridae), in New Zealand

1999 ◽  
Vol 89 (4) ◽  
pp. 295-301 ◽  
Author(s):  
J.A. Wilson ◽  
A.G. Clark ◽  
N.A. Haack
Keyword(s):  
New Zealand ◽  
Piperonyl Butoxide ◽  
Lucilia Cuprina ◽  
Biphasic Response ◽  
Resistance Factors ◽  
Development Of Resistance ◽  
First Instar ◽  
Mixed Function Oxidases ◽  
Resistant Strains ◽  
Independent Effects

AbstractPretreatment of first instar larvae of 28 resistant strains of Lucilia cuprina(Wiedemann) with the inhibitor of microsomal oxidases, piperonyl butoxide, resulted in a biphasic response to the phosphorothioate insecticide diazinon. Analysis of the data revealed a complex response in which both synergist-dependent and independent effects occurred. The responses varied markedly from strain to strain. A laboratory susceptible strain and field strains with resistance factors of less than 20-fold exhibited, in the presence of piperonyl butoxide, an increased LC50 with respect to diazinon whereas those strains with > 20-fold resistance were synergized by the compound. We conclude tentatively that microsomal mixed-function oxidases play a contributory role in the development of resistance and that the variation in synergist effect from strain to strain may be attributed, at least in part, to the two-fold effect of these enzymes on phosphorothioate insecticides such as diazinon.

Cross resistance spectra and effects of synergists in insecticide-resistant strains of Lucilia cuprina (Diptera: Calliphoridae)

1994 ◽  
Vol 84 (3) ◽  
pp. 355-360 ◽  
Author(s):  
A.C. Kotze ◽  
N. Sales
Keyword(s):  
Piperonyl Butoxide ◽  
Lucilia Cuprina ◽  
Cross Resistance ◽  
Resistance Factors ◽  
Deltamethrin Resistance ◽  
Detoxification Systems ◽  
Australian Sheep ◽  
Resistant Strains ◽  
Level Resistance

AbstractCross-resistance spectra were determined in strains of the Australian sheep blowfly, Lucilia cuprina (Wiedemann), which had been pressured for several years in the laboratory with diflubenzuron, butacarb or deltamethrin. Each strain was highly resistant to its selecting chemical (resistance factors > 1000-fold), however, cross-resistance levels were variable and often low. In particular, strains selected with diflubenzuron and butacarb showed very little resistance to deltamethrin (resistance factors <7-fold). Each strain showed resistance levels to diazinon only slightly higher than the highest levels currently detected in field strain larvae. Piperonyl butoxide and triphenyl phosphate significantly synergized each pressured strain with its selecting chemical, suggesting the involvement of both monooxygenases and esterases in the observed resistances. Synergism ratios in each case were greater with piperonyl butoxide. The lack of any alteration in in vitro acetylcholinesterase sensitivity to butacarb inhibition in the butacarb-selected strain, and only low level resistance to DDT in the deltamethrin-selected strain, provided no evidence for target-site insensitivities in these strains. The low-moderate levels of cross-resistance therefore imply the existence of qualitative differences in the detoxification systems in each strain.

scholarly journals Recombinant Human C1 Esterase Inhibitor for the Management of Adverse Events Related to Intravenous Immunoglobulin Infusion in Patients With Common Variable Immunodeficiency or Polyneuropathy: A Pilot Open-Label Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Isaac R. Melamed ◽  
Holly Miranda ◽  
Melinda Heffron ◽  
Joseph R. Harper
Keyword(s):  
Adverse Events ◽  
Intravenous Immunoglobulin ◽  
Common Variable Immunodeficiency ◽  
Treatment Phase ◽  
Open Label ◽  
Ivig Infusion ◽  
C1 Esterase Inhibitor ◽  
Pre Treatment ◽  
Common Variable ◽  
Esterase Inhibitor

It has been hypothesized that low levels of C1 esterase inhibitor (C1-INH), a key inhibitor of the complement pathway, may play a role in the occurrence of adverse events (AEs) associated with intravenous immunoglobulin (IVIG) therapy. This open-label pilot study evaluated C1-INH replacement, with recombinant human C1-INH (rhC1-INH), as a potential therapy for adults requiring IVIG and experiencing AEs. Patients received two rounds of IVIG infusion [pre-treatment phase (no rhC1-INH), 4–8 weeks] and then three rounds of one dose of intravenous rhC1-INH 50 U/kg (maximum, 4,200 U) with subsequent IVIG infusion (treatment phase, 6–12 weeks). Nineteen adults completed the study; all had an autoimmune condition linked to common variable immunodeficiency (CVID) or polyneuropathy, and 57.9% had low baseline C1-INH levels. Mean ± SD total scores improved significantly with the Headache Impact Test (from 62.8 ± 6.2 at pre-treatment to 57.7 ± 9.1 after treatment; mean Δ, −5.0; p = 0.02) and Modified Fatigue Impact Scale (from 59.3 ± 13.1 to 51.2 ± 15.4; mean Δ, −8.1; p = 0.006). Significant improvements in the Migraine Disability Assessment were observed for three of five items (p ≤ 0.002). Mean ± SD C1-INH level increased from 26.8 ± 5.9 mg/dl after the second round of IVIG (pre-treatment) to 32.1 ± 7.8 mg/dl after the third rhC1-INH treatment; functional C1-INH levels increased from 115.8 ± 34.7% to 158.3 ± 46.8%. Future research is warranted to explore the benefit of C1-INH therapy for reduction of IVIG-related AEs, as well as the role of C1-INH in patients with CVID and autoimmune disease.Clinical Trial RegistrationClinicalTrials.gov, identifier NCT03576469.

Section 10. Pyrethroid resistance: resistance breaking pyrethroids

1993 ◽  
Vol 1 ◽  
pp. 83-96 ◽  
Author(s):  
Neil W. Forrester ◽  
Matthew Cahill ◽  
Lisa J. Bird ◽  
Jacquelyn K. Layland
Keyword(s):  
Resistant Strain ◽  
Pyrethroid Resistance ◽  
Residual Activity ◽  
Susceptible Strain ◽  
Piperonyl Butoxide ◽  
Monooxygenase System ◽  
Acid Moiety ◽  
Resistance Factors ◽  
Resistance Breaking ◽  
Alcohol Moiety

SummaryThe structural requirements for designing a resistance breaking pyrethroid to overcome oxidative metabolic pyrethroid resistance in Helicoverpa armigera were studied. A range of pyrethroid structures were tested on a well defined pure breeding pyrethroid resistant strain of H. armigera (homozygous for a metabolic detoxification mechanism fully suppressible by piperonyl butoxide, presumably via a microsomal monooxygenase system). Highest resistance factors were to the ester bonded phenoxybenzyl alcohol pyrethroids, particularly to those with an aromatic acid moiety. Changes to the alcohol moiety alone could overcome most, if not all, resistance. Simple benzyl alcohols were the most effective followed by cyclopentenolones and a methylated biphenyl alcohol. However, the benzylfurylmethyl alcohol (bioresmethrin) was not effective. The incorporation of a synergophore grouping into the alcohol moiety was fully effective for Scott's Py III (methylenedioxyphenyl) and prallethrin (propynyl) but only partially effective for tetramethrin (N-alkyl). Changes to the acid moiety had little effect except for the incorporation of a synergophore methylenedioxyphenyl grouping (Cheminova I) which was just as effective as for the same insertion in the alcohol moiety. The change to a central ether bond from the conventional ester bond lowered resistance. Reversion to an unsubstituted alpha carbon analogue from the conventional alpha cyano group also lowered resistance.Piperonyl butoxide (Pbo) had little effect on pyrethroid toxicity in the susceptible strain except for the single isomers deltamethrin and esfenvalerate. However, it was more than fully effective in overcoming resistance and actually reduced resistance factors to significantly below one in the resistant strain. This indicated the possibility that Pbo could be acting both as a classical monooxygenase inhibitor and a preferential penetration synergist in resistant larvae.Partial or full resolution of racemic mixtures had minimal impact on increasing toxicity in the susceptible strain. However, partially or fully resolved isomers were clearly much more toxic on resistant strains, indicating a possible blocking effect of the inactive isomers during the toxication process with the higher pyrethroid doses applied to resistant larvae. Cis isomers had only slightly higher resistance factors than trans isomers.Seven fully effective resistance breaking pyrethroids were identified in this study and one of these (the simple benzyl alcohol, Series Two) was shown to be equally effective on both adults and larvae of H. armigera. It was also shown to work equally well on laboratory or field material and gave results similar to a pyrethroid/Pbo combination. However, none of the resistance breakers identified so far are able to satisfy all of the requirements necessary for an ideal resistance breaking pyrethroid (i.e. good resistance breaking activity at low rates, photostability, residual activity similar to current pyrethroids and safety to mammals). Factors acting against the possible commercialization of successful resistance breaking compounds are discussed.

scholarly journals Accumulation and Oriented Transport of Ampicillin in Caco-2 Cells from Its Pivaloyloxymethylester Prodrug, Pivampicillin

2005 ◽  
Vol 49 (4) ◽  
pp. 1279-1288 ◽  
Author(s):  
Hugues Chanteux ◽  
Françoise Van Bambeke ◽  
Marie-Paule Mingeot-Leclercq ◽  
Paul M. Tulkens
Keyword(s):  
Multidrug Resistance ◽  
Drug Release ◽  
Intestinal Epithelium ◽  
Atp Depletion ◽  
Intestinal Cells ◽  
Apical Pole ◽  
Cell Lysate ◽  
Nitrophenyl Phosphate ◽  
Significant Release ◽  
Esterase Inhibitor

ABSTRACT Pivampicillin (PIVA), an acyloxymethylester of ampicillin, is thought to enhance the oral bioavailability of ampicillin because of its greater lipophilicity compared to that of ampicillin. The fate of PIVA in intestinal cells and the exact location of its conversion into ampicillin have, however, never been unambiguously established. Polarized Caco-2 cells have been used to examine the handling of PIVA and the release of ampicillin from PIVA by the intestinal epithelium. Experiments were limited to 3 h. Cells incubated with PIVA (apical pole) showed a fast accumulation of ampicillin and transport toward the basolateral medium, whereas PIVA itself was only poorly accumulated and transported. Cells incubated with free ampicillin accumulated and transported only minimal amounts of this drug. Release of ampicillin from cells incubated with PIVA was unaffected by PEPT1 and OCTN2 inhibitors but was sharply decreased after ATP depletion or addition of bis(4-nitrophenyl)-phosphate (BNPP; an esterase inhibitor). PIVA incubated with Caco-2 lysates released free ampicillin, and this release was inhibited by BNPP. Efflux studies showed that the ampicillin that accumulated in cells after incubation with PIVA was preferentially transported out of the cells through the basolateral pole. This efflux was decreased by multidrug resistance-associated protein (MRP) inhibitors (probenecid, MK-571) and by ATP depletion. A phthalimidomethylester of ampicillin that resists cellular esterases failed to cause any significant release (cell lysate) or transport (polarized Caco-2 cells) of ampicillin. These results show that when PIVA is given to Caco-2 cells from their apical pole, ampicillin is released intracellularly and that ampicillin is thereafter preferentially effluxed into the basolateral medium through an MRP-like transporter.

Evaluation of resistance, cross-resistance and synergism of abamectin and teflubenzuron in a multi-resistant field population of Plutella xylostella (Lepidoptera: Plutellidae)

1997 ◽  
Vol 87 (5) ◽  
pp. 481-486 ◽  
Author(s):  
M. Iqbal ◽  
D.J. Wright
Keyword(s):  
Plutella Xylostella ◽  
Maleic Acid ◽  
Diamondback Moth ◽  
Laboratory Strain ◽  
Piperonyl Butoxide ◽  
Diethyl Ester ◽  
Cross Resistance ◽  
Glutathione S Transferases ◽  
Pre Treatment ◽  
Selection Of

AbstractThe efficacy of abamectin (AgrimecR) and teflubenzuron (NomoltR) was assessed by leaf-dip bioassay against larvae of the diamondback moth, Plutella xylostella Linnaeus from a population (SERD3) collected originally in lowland Malaysia in December 1994. Evidence for resistance to both abamectin and teflubenzuron was found in the F7 generation (LC50 ratio of 60 and 24 respectively compared with a laboratory, insecticide-susceptible strain). Selection of sub-populations of SERD3 (F7–F9) with abamectin and teflubenzuron increased the LC50 ratio to 220 and 360 respectively and estimates of realized heritability [h2] were high (c. 0.8 and 0.9) for both compounds. There was no cross-resistance between these compounds in the abamectin and teflubenzuron-selected sub-populations but some indication of negatively-correlated resistance. Topical application of the synergists piperonyl butoxide, S,S,S-tributylphosphorotrithioate and maleic acid diethyl ester to the laboratory strain had no significant effect on the toxicity of abamectin or teflubenzuron in subsequent leaf-dip assays. In contrast, pre-treatment with piperonyl butoxide and S,S,S-tributylphosphorotrithioate significantly increased the toxicity of abamectin (c. 4- and 3-fold) and teflubenzuron (c. 7- and 19-fold) in the abamectin and teflubenzuron-selected sub-populations of SERD3, suggesting that microsomal monoxygenases and/or esterases may be involved in resistance. Pre-treatment with maleic acid diethyl ester only increased the toxicity of abamectin by c. 2-fold and had no significant effect on the toxicity of teflubenzuron, providing limited evidence for the involvement of glutathione-S-transferases in resistance to the former compound alone.

Culture of an organophosphorus-resistant strain ofBoophilus microplus(Can.) and an assessment of its resistance spectrum

1966 ◽  
Vol 56 (3) ◽  
pp. 389-405 ◽  
Author(s):  
R. D. Shaw
Keyword(s):  
Resistant Strain ◽  
Specific Resistance ◽  
Dominant Gene ◽  
Resistance Mechanism ◽  
Tick Control ◽  
Boophilus Microplus ◽  
Test Method ◽  
Organophosphorus Insecticides ◽  
Development Of Resistance ◽  
Low Order

Field observations indicated that a strain ofBoophilus microplus(Can.) in the Rockhampton area in Queensland was resistant to an organophosphorus insecticide, dioxathion (applied as Delnav), which had previously controlled it successfully. Ticks of this strain were despatched to the Cooper Technical Bureau in England, where a culture was established and maintained under selective pressure from dioxathion.The non-parasitic stages of the culture were maintained in an incubator under controlled conditions, and the parasitic stages on cattle in a tick rearing house designed for the purpose. Careful security precautions were taken to ensure that there was no dissemination of tick life outside the confines of the culture. The tick rearing house was provided with double doors, the inner ones of which were screened with copper gauze to prevent the possible transmission of anaplasmosis by biting flies.The activities of 23 insecticides against larvae of this strain and larvae of a strain ofB. microplussusceptible to organophosphorus poisoning were compared. The test method was an immersion technique, usually employing the insecticide in the form of an emulsion. Mortality was assessed 17 hours after treatment. These comparisons indicated that the strain was resistant to the organophosphorus insecticides carbophenothion (62 ×), dioxathion (25 ×), diazinon (15 ×), parathion (10×) and a carbamate, carbaryl (38×). It is suggested that these resistances may be due to a specific mechanism effective against these compounds.Nine other organophosphorus insecticides, one carbamate and rotenone were subject to low-order resistance by this strain significant at P ≤0·05. This was considered to be non-specific resistance.Dioxathion had been in use for tick control on the property concerned for four years before resistance was demonstrated. The property is situated in an area where the tick season lasts for ten months. In other parts of the world, dioxathion has been in use againstBoophilusticks for seven years without the development of resistance to it. The length of time resistance has taken to develop suggests that the resistance mechanism is not the expression of a single dominant gene, as has been demonstrated for dieldrin-resistance.The results suggest that resistance to one or more organophosphorus insecticides will not necessarily prevent the use of other members of this wide and diverse group for tick control. Several of the insecticides shown here to be subject to low-order non-specific resistance are known to be effective tick dips, and one of them, ethion, has been used with success against the resistant strain.An interesting corollary of the results was that the organophosphorus thions showed greater activity than their corresponding oxons against the susceptible strain.

scholarly journals Studies of the acetylcholinesterase from houseflies (Musca domestica L.) resistant and susceptible to organophosphorus insecticides

1975 ◽  
Vol 149 (2) ◽  
pp. 463-469 ◽  
Author(s):  
A L Devonshire
Keyword(s):  
Musca Domestica ◽  
Rate Constants ◽  
Gel Electrophoresis ◽  
Organophosphorus Compounds ◽  
Organophosphorus Insecticides ◽  
Triton X ◽  
Kinetics Of ◽  
Kinetics Of Inhibition ◽  
Single Enzyme

Acetylcholinesterase from the heads of insecticide-resistant and -susceptible houseflies (Musca domestica L.) was studied in vitro. The enzymes could not be distinguished electrophoretically, and their behaviour on polyacrylamide-disc-gel electrophoresis was influenced by the presence of Triton X-100 in both the homogenate and the gels. In the absence of detergent, the acetylcholinesterase was heterogeneous, but behaved as a single enzyme when it was present. By analogy with studies of acetylcholinesterase from other sources, these observations were attributed to aggregation of the enzyme when not bound by membranes. The enzyme from resistant flies was more slowly inhibited than the susceptible enzyme, bimolecular rate constants (ki) differing by approx. 4-20-fold for a range of organophosphorus compounds. The kinetics of inhibition of acetylcholinesterase were consistent with the results of electrophoresis, i.e. they corresponded to those of a single enzyme in the presence of Triton X-100, but a mixture of enzymes in its absence. The susceptibility of the more sensitive components in these mixtures was determined.

Sign in / Sign up

Export Citation Format

Share Document