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The anticancer, antimicrobial, and insecticidal activities of sarcotrocheliol (1) and cholesterol (2) obtained from the soft coral Sarcophyton trocheliophorum (S. trocheliophorum) were intensively studied. According to this study, both compounds 1 and 2 showed potential cytotoxicity towards the human colorectal carcinomaHCT-116 (IC 50 10.4, 11.8 µg/mL) and human liver carcinoma HepG2 cell lines (IC 50 8.8, 12.0 µg/mL), respectively. Compounds 1 and 2 were evaluated as potential inhibitors of caspase-3, a member of the cysteine protease family, which is considered a key enzyme in inducing cell apoptosis. Results showed that compounds 1 and 2 have induced apoptosis via up-regulation of caspase-3. Sarcotrocheliol (1) displayed antimicrobial activity against P. aeruginosa (15 mm), B. subtilis (15 mm), M. luteus (14 mm) and C. albicans (15 mm), with a MIC of 1.5 µg/mL against the reported test microorganisms. On the other hand, cholesterol (2) showed less activity towards P. aeruginosa (10 mm), B. subtilis (14 mm), S. aureus (12 mm) and C. albicans (10 mm) with MICs of 3.0, 1.5, 1.5 and 3.0 µg/mL against the tested microorganisms, respectively. Larvicidal activity revealed that compounds 1 and 2 induced remarkable toxicity against the third instar larvae of the mosquito, Culex pipiens even at concentration of 2 ppm. Adulticidal activity data showed that tested compounds are distinctly potent toxicants against the housefly, Musca domestica adult females. Overall, compound 2induced much more insecticidal activity than 1, and M. domestica adult females were more sensitive to tested compounds than C. pipiens larvae. Computationally, Density Functional Theory (DFT) analyses revealed that compound 2 had a higher dipole moment and lower band gap energy when compared to compound 1. So, compounds 2 is chemically more reactive and less stable than compound 1. According to the molecular docking study against PDB IDs: 3KJF, 5UHF and 1ACJ, compounds 1 and 2 demonstrated their activity mode as anticancer, antimicrobial, and insecticidal agents. The compounds exerted many interactions and showed high binding to the proteins, recognizing their potential as drug candidates with broad bioactivities., Competing Interests: Declarations Conflict of interest The authors declare no conflict of interest. Declarations Ethics approval Not applicable. Human Ethics and Consent to participate Not applicable. Consent for publication Not applicable., (© 2024. The Author(s).)

The house fly (Musca domestica L.) is a ubiquitous fly species commonly associated with confined animal and urban waste storage facilities. It is known for its pestiferous nature and ability to mechanically vector numerous disease-causing pathogens. Effective control of adult house fly populations has traditionally relied upon insecticidal food baits; however, due to the overuse of insecticides, resistance has proven to yield many insecticidal baits and chemical classes less effective. Imidacloprid, the most widely used neonicotinoid, has been formulated and commonly used in house fly baits for over 2 decades. However, widespread evidence of physiological and behavioral resistance to imidacloprid has been documented. While previous studies have investigated the mechanisms of behavioral resistance to imidacloprid in the house fly, it remains unclear whether behavioral resistance is specific to imidacloprid or if behavioral cross-resistance exists to other compounds within the neonicotinoid class of insecticides. The current study used no-choice and choice-feeding bioassays to examine a lab-selected imidacloprid behaviorally resistant house fly colony for cross-resistance to other insecticides in the neonicotinoid chemical class. All flies exhibited high mortality (97-100%) in no-choice assays, even when exposed to imidacloprid, indicating physiological susceptibility to all tested neonicotinoids. House flies exhibited high mortality (98-100%) in choice assays when exposed to all neonicotinoid insecticides tested besides imidacloprid. These results confirm that imidacloprid behavioral resistance is specific to the compound imidacloprid and that alternative neonicotinoids remain viable options for control. Our study showed no evidence of behavioral cross-resistance to other compounds in the neonicotinoid class., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Glutathione S-transferases (GSTs) are an important class of enzymes that facilitate the conjugation of reduced glutathione (GSH) with electrophilic substrates, including some insecticides. Two inhibitors of GSTs, ethacrynic acid (EA) and diethyl maleate (DEM), are often used as diagnostic tools to implicate GST involvement in insecticide resistance, but their modes of action against insect GSTs are largely assumed based on mammalian studies. In mammalian studies, there are two proposed mechanisms of inhibition of GST function by EA and DEM: 1) scavenging or "depleting" cytosolic GSH through non-enzymatic conjugation, and 2) inhibition of GST activity directly by the inhibitor-GSH conjugate (EA-SG and DEM-SG). The objective of this study was to characterize putative inhibitory mechanisms of EA and DEM against insect (house fly) GSTs and the co-factor GSH. Both EA and DEM synergized topical applications of naled and propoxur but not permethrin. As a GSH scavenger, EA was ∼10-fold more potent compared to DEM. Conditions such as pH, GSH concentration, and incubation time significantly affected the ability of both inhibitors to scavenge GSH. EA demonstrated scavenging at a wider pH range than DEM and scavenged GSH at a faster rate than DEM. Whereas EA peak scavenging was observed almost instantly, there was a 54.4 % increase in scavenged GSH for DEM between 0 and 30 min of incubation. Increasing concentration of GSH diminished the effect of scavenging at the highest tested concentrations of both inhibitors. In the presence of both GSH and GSTs in crude homogenate, EA was 300-fold more potent as a GST inhibitor compared to DEM at pH 7.5. No comparison was made at pH 6.5 because the tested concentrations of DEM did not produce enough inhibition to derive an IC 50 value while EA concentrations did. With purified GSTs, EA-SG was 205-fold more potent as an inhibitor compared to DEM-SG, while EA alone was 7.6-fold more potent than EA-SG and 1565-fold more potent than DEM-SG. These findings establish in insects that the insecticide synergists EA and DEM function mainly by scavenging the GST co-factor GSH, with some inhibition due to interactions with GSTs and the inhibitor-GSH conjugates, rather than through interaction between the inhibitors and the GST protein itself. These resulting impacts are two-fold, whereby (i) GSH bioavailability is limited and (ii) the GSH-inhibitor complex attenuates GST-based xenobiotic metabolism., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Decreased cuticular penetration has been documented as a mechanism of resistance in several insects, yet this mechanism remains poorly understood. Levels of resistance conferred, effects of the physicochemical properties on the manifestation of resistance and the effects of different routes of exposure are largely unknown. We recently selected a strain (FlurR) of house fly that was >11,000-fold resistance to fluralaner, and decreased cuticular penetration was one of the mechanisms of resistance (Norris et al., 2023). We sought to isolate the decreased penetration mechanism from FlurR into the background of the susceptible aabys strain, and to characterize the protection it conferred to fluralaner and other insecticides. We successfully isolated the decreased penetration mechanism and found that it conferred 7.1-fold resistance to fluralaner, and 1.4- to 4.9-fold cross-resistance to five other insecticides by topical application. Neither mass, metabolic lability, vapor pressure, nor logP explained the differences in the resistance ratios. The mechanism also conferred cross resistance by residual and feeding exposure, although at reduced levels compared to topical application. Remaining data gaps in our understanding of this mechanism are discussed., (Copyright © 2024. Published by Elsevier Inc.)

Fly control for any species is most effectively implemented in the immature stages when insects can be eliminated before emerging as adults capable of transmitting pathogens or becoming nuisance pests. Yet a limited number of insecticide classes are available for treating larval development sites for dipteran pest species. The most recently introduced class of insecticides in the United States (US) is the isoxazolines, including fluralaner. In the US, fluralaner is currently exclusively labeled for use against ectoparasites in companion animals. However, research has shown that it has a wider effective target range beyond ectoparasites and could be developed as an insecticide for vector control. Here we tested a novel, proprietary, yeast microencapsulated (YME) formulation of fluralaner against the larvae of three pest species: Musca domestica L. (Diptera: Muscidae), Aedes albopictus Skuse (Diptera: Culicidae), and Culicoides sonorensis Wirth and Jones (Diptera: Ceratopogonidae). These species all naturally consume microorganisms as larvae, including yeasts. Fluralaner was successfully microencapsulated in Saccharomyces cerevisiae yeast. YME fluralaner was reconstituted in water at concentrations of 0.00001-0.1 mg/mL (Aedes and Culicoides) or 1-50 mg/mL (Musca) for use in dose-response assays. For each species, the LC 50 at 24 h was estimated using probit analyses. YME fluralaner was highly effective against all species tested (Ae. albopictus LC 50 = 0.000077 mg/mL; C. sonorensis LC 50 = 0.00067 mg/mL; M. domestica LC 50 = 2.58 mg/mL). Additionally, laboratory assays were conducted to determine product reapplication rates using LC 50 rates. Reapplication rates to maintain <50 % emergence were five weeks (Ae. albopictus) and greater than eight weeks (C. sonorensis). The results presented here indicate YME fluralaner is a promising candidate for controlling larval insects that naturally feed on detritus, thereby bypassing cuticular penetration barriers and safely delivering the active ingredient to the target species., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The house fly, Musca domestica, is a cosmopolitan species known for its pestiferous nature and potential to mechanically vector numerous human and animal pathogens. Control of adult house flies often relies on insecticides formulated into food baits. However, due to the overuse of these baits, insecticide resistance has developed to all insecticide classes currently registered for use in the United States. Field populations of house flies have developed resistance to imidacloprid, the most widely used neonicotinoid insecticide for fly control, through both physiological and behavioral resistance mechanisms. In the current study, we conducted a comprehensive analysis of the inheritance and dominance of behavioral resistance to imidacloprid in a lab-selected behaviorally resistant house fly strain. Additionally, we conducted feeding preference assays to assess the feeding responses of genetic cross progeny to imidacloprid. Our results confirmed that behavioral resistance to imidacloprid is inherited as a polygenic trait, though it is inherited differently between male and female flies. We also demonstrated that feeding preference assays can be instrumental in future genetic inheritance studies as they provide direct insight into the behavior of different strains under controlled conditions that reveal, interactions between the organism and the insecticide. The findings of this study carry significant implications for pest management and underscore the need for integrated pest control approaches that consider genetic and ecological factors contributing to resistance., (© 2024 The Authors. Insect Science published by John Wiley & Sons Australia, Ltd on behalf of Institute of Zoology, Chinese Academy of Sciences.)

Extensive traumatic injuries and difficult-to-heal wounds, induced by many circumstances, impose a significant social and economic burden on an annual basis. Thus, innovative wound dressings that encourage wound healing are greatly needed. In this work, we prepared a novel insect chitosan (MCS) using waste pupal shells from housefly (Musca domestica L.) culture. After conducting comparative investigations with commercially available chitosan, it was shown that MCS exhibited comparable qualities and may be used as a substitute source of commercial chitosan. A quaternized chitosan/pullulan/citric acid three-dimensional nanofiber sponge (3D-NS) of natural origin was prepared by electrostatic spinning and gas foaming techniques after MCS was quaternized. In vitro, tests showed that the 3D-NS had a higher liquid absorption capacity than the two-dimensional nanofibrous membrane (2D-NM). Additionally, the 3D-NS showed improved hemostatic, pro-cell proliferation, antibacterial, and anti-inflammatory qualities. In vitro, tests demonstrated that 3D-NS could inhibit the release of inflammatory factors, promote angiogenesis, accelerate collagen deposition, and promote wound contraction. These effects considerably facilitated the healing process of wounds in rats with full-thickness skin damage. In conclusion, the great bioactivity and physicochemical properties of 3D-NS render it an optimal candidate for developing novel wound dressings., Competing Interests: Declaration of competing interest The authors declare that there are no financial or other relationships that might lead to a conflict of interest in the present article. All authors have reviewed the final version of the manuscript and approved it for publication., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The common housefly, Musca domestica, known for transmitting over 100 infections, was studied using green-synthesized Cadmium Sulfide nanoparticles (CdS NPs) from Agaricus bisporus. These CdS NPs were tested on third-instar larvae under laboratory conditions using dipping and feeding methods with concentrations (75, 100, 125, 150, 175, and 200 µg/mL). The toxicity, measured by LC50, was found to be 138 µg/mL for dipping treatment and 123 µg/mL for feeding treatment. Analysis with an energy-dispersive X-ray microanalyzer confirmed Cd accumulation in the larval midgut, indicating penetration of CdS NPs into the organism, which may potentially increase their toxicity. CdS NPs caused disruptions in Heat Shock Protein 70, cell apoptosis, and various biochemical components. Scanning electron microscopy revealed morphological abnormalities in larvae, pupae, and adults exposed to CdS NPs. Ultrastructural examination showed significant midgut tissue abnormalities in larvae treated with 123 µg/mL of CdS NPs. Our study demonstrated that green-synthesized CdS NPs from A. bisporus can effectively control the development of M. domestica larvae., (© 2024. The Author(s).)

The synthesized pyrazolopyrimidine derivatives conjugated with selenium nanoparticles were prepared via a reaction of pyrazolone 1 with aryl-aldehyde and malononitrile or 3-oxo-3-phenylpropanenitrile in the presence ammonium acetate or pipridine using an ultrasonic bath as a modified method in the organic synthesis for such materials. The structure of the synthesized compounds was elucidated through various techniques. All the synthesized pyrazolopyrimidines were used in the synthesis of selenium nanoparticles (SeNPs). These nanoparticles were confirmed using UV-spectra, Dynamic Light scattering and (TEM) techniques. The larvicidal efficiency;of the synthesized;compounds; was investigated against some strains such as Culex pipiens;and Musca domestica larvae. Bioassay test showed pyrazolopyrimide derivatives to exhibit an acceptable larvicidal;bio-efficacy. The derivative (3) exhibited;the highest;efficiency for more than; lab strains of both species. Moreover, C. pipiens larvae were more sensitive towards the examined compounds than M. domestica. The field;strain displayed lower affinity for the 2 folds compounds. Some biochemical changes were tracked through analysis of insect main metabolites (protein, lipid and carbohydrate), in addition to measuring the changes in seven enzymes after treatment. Generally, there was a reduction in the protein, lipids and carbohydrates after treatment with all tested compounds. Moreover, a decrement was noticed for acetylcholine esterase and glutathione;S-transferase; enzymes. There was an increment in the acid;phosphatase; and alkaline phosphatase. In addition, there was elevation in Phenoloxidase level but it noticed the declination in both Cytochrome P450 and Ascorbate peroxidase activity after treatment both flies with derivatives of selenium-nanoparticles in both lab and field strain. Generally, the experiments carried out indicate that antioxidant and detoxification enzymes may play a significant role in mechanism of action of our novel nanocompounds. The cytotoxicity of the synthesized compounds and conjugated with SeNPs showed enhanced compatibility with human normal fibroblast cell line (BJ1) with no toxic effect., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The house fly, Musca domestica (Linnaeus) (Diptera: Muscidae), is a significant threat to human and animal health and is also resistant to a variety of insecticides. Plant-derived benzoates are known to have insecticidal activities against various insects. In this study, the larvicidal, pupicidal, and adulticidal activities of benzoate derivatives (benzyl alcohol BA, benzyl benzoate BB, and methyl benzoate MB) were assessed and investigated for their effects on larval structure and acetylcholinesterase activity. Six concentrations (2.5 to 100 mg/mL) of benzoate derivatives were applied to larvae and pupae through the residual film method and topical application, respectively. Meanwhile, concentrations from 0.625 to 50 mg/L air were applied to adult flies through a fumigation assay. BA and MB achieved promising results against larvae with LC 50 values of 10.90 and 11.53 mg/mL, respectively. Moreover, BA killed 100% of the larvae at a concentration of 25 mg/mL, and MB achieved the same effect at a concentration of 50 mg/mL. Regarding the pupicidal activity, MB showed a percentage inhibition rate (PIR) of 100% at a concentration of 100 mg/mL, while the same effect was achieved by BA at a concentration of 50 mg/mL. Meanwhile, BB did not show any effect on the larvae or pupae at any of the tested concentrations. Moreover, the scanning microscopy observations on the treated larvae by BA and MB estimated flaccid and deformity in the larva body with a shrunken cuticle. Additionally, both BA and MB suppress nerve signal transmission by inhibiting acetylcholinesterase. In conclusion, the results of this study indicate that BA and MB may be useful in control housefly populations. These substances cause severe muscular relaxation and deformities in insects., (© 2024. Sociedade Entomológica do Brasil.)

Musca domestica L., a common housefly, and Culex quinquefasciatus mosquito are quite well-known pests that can transfer a wide range of diseases to humans as well as animals. In this study, various isoborneol derivatives including esters, ethers, and thioethers were synthesized from isoborneol under mild conditions. These derivatives were evaluated for inhibition of house-fly M. domestica adults and Cx. quinquefasciatus larvae. Two of the synthesized isoborneol ester derivatives (2 and 3) showed good activity against both insect species. Additional two derivatives (6 and 9) were active against M. domestica L., and the derivatives (1-3, 8) were active against Cx. quinquefasciatus larvae., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Musca flies (Diptera: Muscidae) have been found culpable in the mechanical transmission of several infectious agents, including viruses, bacteria, protozoans, and helminths, particularly in low-income settings in tropical regions. In large numbers, these flies can negatively impact the health of communities and their livestock through the transmission of pathogens. In some parts of the world, Musca sorbens is of particular importance because it has been linked with the transmission of trachoma, a leading cause of preventable and irreversible blindness or visual impairment caused by Chlamydia trachomatis, but the contribution these flies make to trachoma transmission has not been quantified and even less is known for other pathogens. Current tools for control and monitoring of house flies remain fairly rudimentary and have focused on the use of environmental management, insecticides, traps, and sticky papers. Given that the behaviors of flies are triggered by chemical cues from their environment, monitoring approaches may be improved by focusing on those activities that are associated with nuisance behaviors or with potential pathogen transmission, and there are opportunities to improve fly control by exploiting behaviors toward semiochemicals that act as attractants or repellents. We review current knowledge on the odor and visual cues that affect the behavior of M. sorbens and Musca domestica, with the aim of better understanding how these can be exploited to support disease monitoring and guide the development of more effective control strategies., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

As the first marketed phenylpyrazole insecticide, fipronil exhibited remarkable broad-spectrum insecticidal activity. However, it poses a significant threat to aquatic organisms and bees due to its high toxicity. Herein, 35 phenylpyrazole derivatives containing a trifluoroethylthio group on the 4 position of the pyrazole ring were designed and synthesized. The predicted physicochemical properties of all of the compounds were within a reasonable range. The biological assay results revealed that compound 7 showed 69.7% lethality against Aedes albopictus ( A. albopictus ) at the concentration of 0.125 mg/L. Compounds 7 , 7g , 8d, and 10j showed superior insecticidal activity for the control of Plutella xylostella ( P. xylostella ). Notably, compound 7 showed similar insecticidal activity against Aphis craccivora ( A. craccivora ) compared with fipronil. Potential surface calculation and molecular docking suggested that different lipophilicity and binding models to the Musca domestica ( M. domestica ) gamma-aminobutyric acid receptors may be responsible for the decreased activity of the tested derivatives. Toxicity tests indicated that compound 8d (LC 50 = 14.28 mg/L) induced obviously 14-fold lower toxicity than fipronil (LC 50 = 1.05 mg/L) on embryonic-juvenile zebrafish development.

The dinoflagellate Karenia brevis is a causative agent of red tides in the Gulf of Mexico and generates a potent family of structurally related brevetoxins that act via the voltage-sensitive Na + channel. This project was undertaken to better understand the neurotoxicology and kdr cross-resistance to brevetoxins in house flies by comparing the susceptible aabys strain to ALkdr (kdr) and JPskdr (super-kdr). When injected directly into the hemocoel, larvae exhibited rigid, non-convulsive paralysis consistent with prolongation of sodium channel currents, the known mechanism of action of brevetoxins. In neurophysiological studies, the firing frequency of susceptible larval house fly central nervous system preparations showed a > 200% increase 10 min after treatment with 1 nM brevetoxin-3. This neuroexcitation is consistent with the spastic paralytic response seen after hemocoel injections. Target site mutations in the voltage-sensitive sodium channel of house flies, known to confer knockdown resistance (kdr and super-kdr) against pyrethroids, attenuated the effect of brevetoxin-3 in baseline firing frequency and toxicity assays. The rank order of sensitivity to brevetoxin-3 in both assays was aabys > ALkdr > JPskdr. At the LD 50 level, resistance ratios for the knockdown resistance strains were 6.9 for the double mutant (super-kdr) and 2.3 for the single mutant (kdr). The data suggest that knockdown resistance mutations may be one mechanism by which flies survive brevetoxin-3 exposure during red tide events., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Controlling housefly populations relies on the use of insecticides, which inevitably leads to the development of resistance. A better and more comprehensive understanding of the spatial and temporal distribution of resistance could guide the control of houseflies. However, most studies on housefly resistance in China are scattered and poorly coordinated. We collected resistance data from houseflies in the published literature and from the vector biomonitoring system of the Chinese Center for Disease Control and Prevention. A 5- or 10-year resolution was used to study the temporal dynamics of resistance to five commonly used insecticides: deltamethrin, permethrin, beta-cypermethrin, dichlorvos, and propoxur. ArcGIS was used to visualize their spatial distributions. The correlation between year and resistance coefficient was determined using SPSS 26.0 and RStudio to explore the changes in resistance over the years. A total of 2128 data were included in this study, ranging from 1982 to 2022, based on which we found significant increases in resistance over the past forty years for the five studied insecticides. Among them, pyrethroids had the most strikingly elevated resistance level and were mainly distributed in the northern and southeastern coastal areas. Dichlorvos and propoxur had intermediate increases in resistance, and most of these increases were identified in North China and the Yangtze River. Housefly resistance to commonly used insecticides in China is increasing and spatially heterogeneous. This finding also highlights the necessity of continuous routine surveillance of housefly resistance, which could guide future housefly control operations and slow the development of resistance., (Copyright © 2024. Published by Elsevier Inc.)

The housefly (Musca domestica) is a common insect species with only a few recurrent bacterial taxa in its gut microbiota, because the numerous microbial acquisition routes in its septic habitats can favor transient microbes. Here, we investigated the role of the diet on the microbiota and the developmental success of a housefly strain reared on three substrates. We used a control wheat bran-based substrate, and added clotted cream and sucrose to make a high-fat, and a high-sugar substrate, respectively. The conducted survey revealed that, in contrast to the high-fat diet, the high-sugar diet caused lower developmental success and less diverse microbiota, in which several lactobacilli were replaced with Weissella bacterial phylotypes. Cultures with sucrose as the sole carbon source confirmed that a Weissella confusa strain, isolated from larvae, could utilize sucrose more efficiently than other tested lactic acid bacteria; a result also supported by gene function prediction analysis. Enhancing the rearing substrate with Limosilactobacillus fermentum and Lactiplantibacillus plantarum strains, which were isolated from control larvae, could not only revert the negative effect of the high-sucrose diet on development, but also increase the gut bacterial diversity. In our study, we show that the microbiota shifts in response to the high-sucrose diet did not benefit the host, that showed lower developmental success. In contrast, high-sucrose favored specific components of the microbiota, that continued to be enriched even after multiple generations, outcompeting beneficial bacteria. Also, microbiome manipulation showed the potential of probiotics to rescue host performance and restore the microbiome., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Society for Microbial Ecology.)

A number of novel annulated pyrazolopyranopyrimidines were prepared via reaction of iminoether of the corresponding 6-amino-5-cyano-pyrano[2,3-c]pyrazole derivative 1 with different nitrogen nucleophiles. The structure of the synthesized compounds was deduced based on IR, MS, 1 H NMR and 13 C NMR spectroscopic data. The larvicidal potency of the synthesized compounds against the lab and field strains of Culex pipiens and Musca domestica larvae was evaluated and the structure-activity relationship (SAR) was discussed. The assay revealed that the tested pyranopyrazole derivatives exhibited good larvicidal bio-efficacy whereas iminoether 4 exhibited the highest efficiency, for lab more than field strains of both species. Also, M. domestica larvae were more sensitive to tested compounds than C. pipiens. The field strain showed low resistance ratios to all compounds with only about 2 folds. The inhibitory effects of synthesized molecules on nAChRs were evaluated by molecular docking. Moreover, the cytotoxicity of the newly synthesized compounds against normal human fibroblasts (WI-38) was investigated. The cytotoxic assay showed that derivatives 4 and 5 were not harmful to normal fibroblasts., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The house fly (Musca domestica Linnaeus) is an important disease vector. Insecticide resistance is an obstacle to effective house fly control. Previous studies have demonstrated that point mutations in acetylcholinesterase (Ace), carboxylesterase (MdαE7) and voltage-sensitive sodium channel (Vssc), and over-expression of CYP6D1v1 confer insecticide resistance in the house fly. However, information about the status and underlying mechanisms of insecticide resistance in Kazakhstani house flies is lacking. In this study, we investigated the occurrence of genetic mutations associated with insecticide resistance in field house flies collected at six different locations in southern Kazakhstan. Four mutations (V260L, G342A/V, and F407Y) in Ace and three mutations (G137D and W251L/S) in MdαE7 were detected with appreciable frequencies. Notably, haplotypes carrying triple-loci mutations in Ace and double mutations in MdαE7 were found in Kazakhstan. The L1014H and L1014F mutations in Vssc, and CYP6D1v1 resistance allele were detected at a low frequency in some of the six investigated house fly populations. Phylogenetic analyses of haplotypes supported multiple origins of resistance mutations in Ace and MdαE7. These observations suggest that house flies in southern Kazakhstan may exhibit significant resistance to organophosphates and carbamates. Regular monitoring of insecticide resistance is recommended to achieve effective house fly control by chemical agents in southern Kazakhstan., (© The Author(s) 2021. Published by Oxford University Press on behalf of Entomological Society of America.All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Musca sorbens is a synanthropic filth fly that aggressively attacks people to feed from mucous membranes of the eyes, nose or mouth, from open sores, or from sweat. It has long been suspected that this fly contributes to the transmission of eye infections, particularly trachoma, and recent work has added to the evidence base that M. sorbens is a trachoma vector in Ethiopia. There are few options to control M. sorbens, largely due to a lack of evidence. Space spraying with insecticides is effective, but an environmentally sound and long-term sustainable solution would be better, for example, mass trapping. We tested commercially available and homemade trap types in a pilot (laboratory) study and three field studies. A homemade design, built from a bucket and two empty water bottles, baited with a commercially available lure, The Buzz, was found to be most effective. This trap caught 3848 M. sorbens over 26 trap 'events' (3- or 4-day periods); mean/median per 24 h 43.6 (standard deviation 137.10)/2.25 (IQR 0.25-12.67). The Buzz lure is cheap and effective for 4 weeks, and trap components cheap and locally available. Further studies are needed to understand the impact of this trap on local fly populations and the local transmission of trachoma., (© 2021. The Author(s).)

Coumarin (2H-1-benzopyran-2-one) is a phenolic compound derived from the shikimate pathway and synthesized by various medicinal and aromatic plants as parent molecule of a large group of secondary metabolites, namely coumarins. Its main utilization is as fixative in perfumes and flavour enhancer. Given its role as phytoalexin and phagodepression activity, herein we evaluated for the first time its efficacy against several insect species: the green peach aphid, Myzus persicae , the moth Spodoptera littoralis , the housefly, Musca domestica and the filariasis vector Culex quinquefasciatus . Two non-target species were also included in our toxicity evaluation experiments: the ladybug Harmonia axyridis and the earthworm Eisenia fetida . Results highlighted remarkable selectivity of coumarin, being highly toxic to M . persicae aphids (LC 50(90) values of 1.3(1.9) mg L -1 ) and friendly to natural enemies of aphids as well as soil invertebrates.

The fumigant and topical activities exhibited by 27 plant-derived essentials oils (EOs) on adult M. domestica housefly are predicted through the Quantitative Structure-Activity Relationship (QSAR) theory. These molecular structure based calculations are performed on 253 structurally diverse compounds from the EOs, where the number of constituents in each essential oil mixture varies between 2 to 24. A large number of 86,048 non-conformational mixture descriptors are derived as linear combinations of the molecular descriptors of the EO components. Two strategies are compared for the mixture descriptor formulation, which consider or avoid the use of the chemical composition. The multivariable linear regression QSAR models of the present work are useful for fumigant and topical applications, describing predictive parallelisms for the insecticidal activity of the analysed complex mixtures.

This study was conducted to determine the susceptibility and resistance of some house fly strains of Musca domestica L. to the insect growth regulator insecticides triflumuron and pyriproxyfen in some locations in Riyadh city. Field-collected strains of M. domestica L. from five sites in Riyadh city that represented five slaughterhouse sites where flies spread significantly were tested against triflumuron and pyriproxyfen. Triflumuron LC50 values for the five collected strains ranged from 2.6 to 5.5 ppm, and the resistance factors (RFs) ranged from 13-fold to 27-fold that of the susceptible laboratory strain. Pyriproxyfen LC50 values for the field strains ranged from 0.9 to 1.8 ppm with RFs of 3-fold to 5-fold. These results indicate that pyriproxyfen is an effective insecticide to control house flies and should be used in rotation with other insecticides in the control programs applied by Riyadh municipality., Competing Interests: The authors have declared that no competing interests exist.

The Tibellus oblongus spider is an active predator that does not spin webs and remains poorly investigated in terms of venom composition. Here, we present a new toxin, named Tbo-IT2, predicted by cDNA analysis of venom glands transcriptome. The presence of Tbo-IT2 in the venom was confirmed by proteomic analyses using the LC-MS and MS/MS techniques. The distinctive features of Tbo-IT2 are the low similarity of primary structure with known animal toxins and the unusual motif of 10 cysteine residues distribution. Recombinant Tbo-IT2 (rTbo-IT2), produced in E. coli using the thioredoxin fusion protein strategy, was structurally and functionally studied. rTbo-IT2 showed insecticidal activity on larvae of the housefly Musca domestica (LD 100 200 μg/g) and no activity on the panel of expressed neuronal receptors and ion channels. The spatial structure of the peptide was determined in a water solution by NMR spectroscopy. The Tbo-IT2 structure is a new example of evolutionary adaptation of a well-known inhibitor cystine knot (ICK) fold to 5 disulfide bonds configuration, which determines additional conformational stability and gives opportunities for insectotoxicity and probably some other interesting features.

Pesticides are used to control and combat insects and pests in the agricultural sector, households, and public health programs. The frequent and disorderly use of these pesticides may lead to variety of undesired effects. Therefore, natural products have many advantages over to synthetic compounds to be used as insecticides. The goal of this study was to find natural products with insecticidal potential against Musca domestica and Mythimna separata. To achieve this goal, we developed predictive QSAR models using MuDRA, PLS, and RF approaches and performed virtual screening of 117 natural products. As a result of QSAR modeling, we formulated the recommendations regarding physico-chemical characteristics for promising compounds active against Musca domestica and Mythimna separata. Homology models were successfully built for both species and molecular docking of QSAR hits vs known insecticides allowed us to prioritize twenty-two compounds against Musca domestica and six against Mythimna separata. Our results suggest that pimarane diterpenes, abietanes diterpenes, dimeric diterpenes and scopadulane diterpenes obtained from aerial parts of species of the genus Calceolaria (Calceolariaceae: Scrophulariaceae) can be considered as potential insecticidal., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

To control the development of resistance to conventional insecticides acting as γ-aminobutyric acid (GABA) receptor antagonists (e.g., fipronil), new GABAergic 5,5-disubstituted 4,5-dihydropyrazolo[1,5- a ]quinazolines were designed via a scaffold-hopping strategy and synthesized with a facile method. Among the 50 target compounds obtained, compounds 5a , 5b , 7a , and 7g showed excellent insecticidal activities against a susceptible strain of Plutella xylostella (LC 50 values ranging from 1.03 to 1.44 μg/mL), which were superior to that of fipronil (LC 50 = 3.02 μg/mL). Remarkably, the insecticidal activity of compound 5a was 64-fold better than that of fipronil against the field population of fipronil-resistant P. xylostella . Electrophysiological studies against the housefly GABA receptor heterologously expressed in Xenopus oocytes indicated that compound 5a could act as a potent GABA receptor antagonist, and IC 50 was calculated to be 32.5 nM. Molecular docking showed that the binding poses of compound 5a with the housefly GABA receptor can be different compared to fipronil, which explains the effectiveness of compound 5a against fipronil-resistant insects. These findings have suggested compound 5a as a lead compound for a novel GABA receptor antagonist controlling field-resistant insects and provided a basis for further design, structural modification, and development of 4,5-dihydropyrazolo[1,5- a ]quinazoline motifs as new insecticidal GABA receptor antagonists.

Insecticide resistance in pest populations is an increasing problem in both urban and rural settings caused by over-application of insecticides and lack of rotation among chemical classes. The house fly (Musca domestica L.) is a cosmopolitan fly species implicated in the transmission of numerous pathogens, and which can be extremely pestiferous when present in high numbers. The evolution of insecticide resistance has long been documented in house flies, with resistance reported to all major insecticide classes. House fly resistance to imidacloprid, the most widely used neonicotinoid insecticide available for fly control, has been selected for in field populations through both physiological and behavioral resistance mechanisms. In the current study, house flies collected from a southern California dairy were selectively bred for behavioral resistance to imidacloprid, without increasing the physiological resistance profile of the selected flies. Flies were also successfully selected for behavioral susceptibility to imidacloprid. The rapid selection for either behavioral resistance or behavioral susceptibility suggests that inheritable alleles conferring behavioral resistance were already present in the wild-type fly population collected from the dairy site. The methods used for the specific selection of behavioral resistance (or susceptibility) in the fly population will be useful for further studies on the specific mechanisms conferring this resistance. House fly behavioral resistance was further investigated using behavioral observation and feeding preference assays, with resistance determined to be both contact-dependent and specific to the insecticide (imidacloprid) rather than to a non-insecticidal component of a bait matrix as previously documented., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America.All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Veterinary and medical entomologists who are involved in research on pest control often need to perform dose-response bioassays and analyze the results. This article is meant as a beginner's guide for doing this and includes instructions for using the free program R for the analyses. The bioassays and analyses are described using previously unpublished data from bioassays on house flies, Musca domestica Linnaeus (Diptera: Muscidae), but can be used on a wide range of pest species. Flies were exposed topically to beta-cyfluthrin, a pyrethroid, or exposed to spinosad or spinetoram in sugar to encourage consumption. LD50 values for beta-cyfluthrin in a susceptible strain were similar regardless of whether mortality was assessed at 24 or 48 h, consistent with it being a relatively quick-acting insecticide. Based on LC50 values, spinetoram was about twice as toxic as spinosad in a susceptible strain, suggesting a benefit to formulating spinetoram for house fly control, although spinetoram was no more toxic than spinosad for a pyrethroid-resistant strain. Results were consistent with previous reports of spinosad exhibiting little cross-resistance. For both spinosad and spinetoram, LC50 values were not greatly different between the pyrethroid-resistant strain and the susceptible strain., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America.)

Housefly, Musca (M) domestica L. (Diptera: Muscidae) is a pervasive insect that transmits a variety of pathogens to humans and livestock. Although numerous synthetic pesticides are available to combat houseflies, their ecological and toxicological concerns have led to the exploration of natural products as safer alternatives. The present work was designed to develop an essential oil based controlled-release evaporating tablet (EO-CRT) and investigate its repellency against M. domestica. This study assesses the toxicological impacts of the EO-CRT following its sub-chronic inhalation exposure. Briefly, repellent activity of fourteen essential oils viz. lemon grass, bergamot, mentha, basil, camphor, lavender, clove, patchouli, rosemary, cinnamon, eucalyptus, citronella, jasmine and wild turmeric against M. domestica were screened using the 'Y'-tube olfactometer. The synergistic activity of the best four oils, under preliminary screening, were further evaluated by double and triple blending. The best combination of three oils were finalized for optimization with 17-run, 3-factor, 3-level Box-Behnken design. This was then employed to construct polynomial models and predict the best optimized formulation EO-CRT. EO-CRT was characterized by Differential Scanning Calorimetry (DSC) and Gas Chromatography-Mass Spectroscopy (GC-MS). The efficacy of the EO-CRT against M. domestica was assessed by attraction and repellent assay. Chest X-ray, histopathology and scanning electron microscopy of the exposed lung was performed to study EO-CRT's sub-chronic toxicity on Wistar rats. The EO-CRT showed slow release up to a period of 10 days at room temperature, exhibited 100% repellency (%Error=1.237) against M. domestica and was found to possess all the characteristics of an ideal formulation. Sub-chronic toxicity study further revealed the non-toxic nature of the EO-CRT. Thus, our study provides an assurance that the formulated EO-CRT could be effective not only in repelling the nuisance pest, M. domestica, in human dwellings, but also in minimizing the mechanical transmission of pathogens by it., Competing Interests: Declaration of Competing Interest The authors declare no conflicts associated with this work., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The house fly, Musca domestica L. (Diptera: Muscidae), is an insect pest of public health and veterinary importance. Spiromesifen is a new chemistry insecticide widely used for the management of sucking insect pests of vegetables and crops. In the present study, assessment of resistance risk and fitness costs associated with spiromesifen resistance in M. domestica was studied. Moreover, stability of resistance to spiromesifen and other tested insecticides (fipronil, spinosad, and bifenthrin) was evaluated in the spiromesifen-selected-strain (SPIRO-SEL-POP). After 7-generations of selection with spiromesifen, SPIRO-SEL-POP developed 108.76-fold resistance compared with the unselected strain (UNSEL-POP). The estimated value of realized heritability was 0.59 for spiromesifen resistance. Due to withdrawal of spiromesifen selection for five generations (F 6 -F 10 ) on SPIRO-SEL-POP, a decline in LC 50 values against spiromesifen, spinosad and bifenthrin was 0.16, 0.14 and 0.13-folds, respectively. In biological trait experiments, larval weight of Cross 1 (SPIRO-SEL-POP♀ × UNSEL-POP♂) and SPIRO-SEL-POP was significantly lower than that of Cross 2 (SPIRO-SEL-POP♂ × UNSEL-POP♀) and UNSEL-POP. Pupal weight of SPIRO-SEL-POP was higher when compared with Cross 1 while it was similar to that of Cross 2 and UNSEL-POP. Adult emergence rate of UNSEL-POP was higher than Cross 1 , but similar to the Cross 2 and SPIRO-SEL-POP. The SPIRO-SEL-POP and Cross 1 showed the lowest relative fitness when compared with USEL-POP and Cross 2 . Intrinsic rate of natural increase of SPIRO-SEL-POP was much lower than that of UNSEL-POP and Cross 2 followed by Cross 1 . The SPIRO-SEL-POP exhibited lower biotic potential when compared with UNSEL-POP and Cross 2 but similar to Cross 1 . Fecundity and hatching rates were lower in SPIRO-SEL-POP compared to UNSEL-POP. It could be concluded that spiromesifen resistance in M. domestica comes with a cost and is instable. Therefore, spiromesifen rotation with other insecticides and withdraw of its usage for some period could help to sustain its efficacy by delaying the development of resistance., Competing Interests: Declaration of Competing Interest All the authors hereby declared no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In this study, metabolites involved in the free-biomass filtrates for three endophytic actinomycetes of Streptomyces capillispiralis Ca-1, Streptomyces zaomyceticus Oc-5, and Streptomyces pseudogriseolus Acv-11 were used as biocatalysts for green synthesis of silver nanoparticles (Ag-NPs). Characterization of biosynthesized Ag-NPs was accomplished using UV-Vis spectroscopy, X-ray diffraction patterns (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM-EDX), transmission electron microscopy (TEM), and particle size analyzer. The biosynthesized Ag-NPs showed maximum surface plasmon resonance (SPR) at 440 for strain Ca-1 and 450 for both strains of OC-5 and Acv-11. Nanoparticle spherical shape was recorded with size ranging from 23.77 to 63.14 nm, 11.32 to 36.72 nm, and 11.70 to 44.73 nm for Ca-1, Oc-5, and Acv-11, respectively. SEM-EDX analysis exhibited the weight percentages of 17.3, 22.3, and 48.7% for Ag-NPs synthesized by strains Ca-1, Oc-5 and Acv-11, respectively. The activities of biosynthesized Ag-NPs were concentration dependent and the obtained results confirmed the efficacy of Ag-NPs as antimicrobial agents against Gram-positive and Gram-negative bacteria as well unicellular and multicellular fungi. The MIC for Gram-positive bacteria, Gram-negative bacteria (E. coli), and eukaryotic microorganisms was 0.25 mM with clear zone ranging from 10.3 to 14.6 mm, while MIC for Pseudomonas aeruginosa was 1.0 mM for Ag-NPs synthesized by strain Ca-1 and 0.25 mM for those synthesized by strains Oc-5 and Acv-11. Moreover, Ag-NPs exhibited antimicrobial activity against four plant pathogenic fungi represented by Alternaria alternata, Fusarium oxysporum, Pythium ultimum, and Aspergillus niger at 2.0, 1.5, 1.0, and 0.5 mM of Ag-NPs with different degree. In vitro assessment of the antioxidant efficacy of biosynthesized Ag-NPs was achieved by scavenging assay of H 2 O 2 , reducing power of Fe 3+ , or total antioxidant assay. The results showed that antioxidant activities of Ag-NPs were concentration dependent with the highest activity at Ag-NP concentration of 2.0 mM. Furthermore, the biosynthesized NPs have prospective bioinsecticidal activity against Culex pipiens and Musca domestica. Green synthesis of NPs could be quite potential for the development of new bioactive compounds used in different biomedical applications.

Cadmium (Cd) is a widespread environment contaminant due to the development of electroplating and metallurgical industry. Cd can be enriched by organisms via food chain, causing the enlarged environmental problems and posing threats to the health of humans. Polydatin (PD), a natural stilbenoid compound derived from Polygonum cuspidatum, shows pronouncedly curative effect on oxidative damage. In this work, the protective effects of PD on oxidative damage induced by Cd in Musca domestica (housefly) larvae were evaluated. The larvae were exposed to Cd and/or PD, subsequently, the oxidative stress status, mitochondria activity, oxidative phosphorylation efficiency, and survival rate were assessed. Cd exposure generated significant increases of malondialdehyde (MDA), reactive oxygen species (ROS) and 8-hydroxy-2-deoxyguanosine (8-oxoG) in the housefly larvae, causing mitochondrial dysfunction and survival rate decline. Interestingly, pretreatment with PD exhibited obviously mitochondrial protective effects in the Cd-exposed larvae, as evidenced by reduced MDA, ROS and 8-oxoG levels, and increased activities of superoxide dismutase (SOD), mitochondrial electron transfer chain, and mitochondrial membrane potential, as well as respiratory control ratio. These results suggested that PD could attenuate Cd-induced damage via maintaining redox balance, stimulating SOD activity, and regulating mitochondria activity in housefly larvae. As a natural polyphenolic chemical, PD can act as a potential candidate compounds to relieve Cd injury., Competing Interests: Declaration of competing interest The authors declare they have no actual or potential competing financial interests., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Two unique housefly strains, PSS and N-PRS (near-isogenic line with the PSS), were used to clarify the mechanisms associated with propoxur resistance in the housefly, Musca domestica. The propoxur-selected resistant (N-PRS) strain exhibited >1035-fold resistance to propoxur and 1.70-, 12.06-, 4.28-, 57.76-, and 57.54-fold cross-resistance to beta-cypermethrin, deltamethrin, bifenthrin, phoxim, and azamethiphos, respectively, compared to the susceptible (PSS) strain. We purified acetylcholinesterase (AChE) from the N-PRS and PSS strains using a procainamide affinity column and characterized the AChE. The sensitivity of AChE to propoxur based on the bimolecular rate constant (K i ) was approximately 100-fold higher in the PSS strain compared to the N-PRS strain. The cDNA encoding Mdace from both the N-PRS strain and the PSS strain were cloned and sequenced using RT-PCR. The cDNA was 2073 nucleotides long and encoded a protein of 691 amino acids. A total of four single nucleotide polymorphisms (SNPs), I162M, V260L, G342A, and F407Y, were present in the region of the active site of AChE from the N-PRS strain. The transcription level and DNA copy number of Mdace were significantly higher in the resistant strain than in the susceptible strain. These results indicated that mutations combined with the up-regulation of Mdace might be essential in the housefly resistance to propoxur.

Toll-like receptors (TLRs) are the earliest reported pathogen recognition receptors (PRRs), and these receptors play pivotal roles in the innate immune system. Systematic studies of TLR family at the genome-wide level are important to understand its functions but are currently lacking in the insect lineage. Here, 6 TLR genes were identified and characterized in housefly (Musca domestica). The TLR genes of housefly were classified into five families according to the phylogenetic analysis of insect TLRs. The domain organization analyses indicated that the TLRs were composed by three major components: a leucine-rich repeat (LRR) domain, a transmembrane region (TM) and a Toll/interleukin-1 receptor (TIR) domain. Primary and tertiary structure analysis showed that the ectodomains of arthropod TLRs were longer than that of other phyla or classes. The mRNA expression levels of all 6 TLRs downregulated in the resistant housefly strain. Moreover, the expression levels of 6 TLRs varied between tissue and gender. Additionally, the 3D structures of the TIR domain were highly conserved during evolution. Collectively, these results help elucidate the crucial roles of TLRs in the immune response of housefly and provide a foundation for further understanding of innate immunity of the housefly., Competing Interests: Declaration of competing interest The authors declare no competing interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Thymus alternans and Teucrium montanum subsp. jailae are medicinal and aromatic plants, typical of Slovakian flora, producing bioactive essential oils. In the present study, we evaluated the insecticidal potential of the essential oils, obtained by hydrodistillation from the plant aerial parts and analysed by GC-MS, as insecticidal agents. For the purpose, they were assayed against three insect species acting as agricultural pests or vectors of medical relevance, such as the common housefly, Musca domestica L., the lymphatic filariasis vector, Culex quinquefasciatus and the Egyptian cotton leafworm Spodoptera littoralis; α-cypermethrin was tested as positive control. The two essential oils exhibited a different chemical profile, with monoterpenes and sesquiterpenes being the main fractions in the essential oils from Th. alternans and T. montanum subsp. jailae, respectively. Insecticidal tests showed that the T. montanum essential oil was effective against S. littoralis (LD 50(90)  = 56.7 (170.0) μg larva -1 ) and Cx. quinquefasciatus larvae (LC 50(90)  = 180.5 (268.7) mg L -1 ), whereas T. alternans essential oil displayed good toxicity against M. domestica adults (LD 50(90)  = 103.7 (223.9) μg adult -1 ). Overall, our results add useful knowledge about the potential of Slovakian flora as a source of botanicals for the eco-friendly management of insect pests and vectors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Marsh rosemary (Ledum palustre, Ericaceae) has been widely used in the traditional medicine of various regions worldwide, and as insect repellent. Little is known on its essential oil insecticidal potential. This study explored the insecticidal effects of the essential oil obtained from L. palustre growing in Poland on selected insect pests and vectors. GC-MS analysis evidenced an uncommon chemotype characterized by ascaridole (35.3% as sum of cis-ascaridole and isoascaridole) and p-cymene (25.5%). The essential oil was effective against Culex quinquefasciatus, Spodoptera littoralis and Musca domestica, showing LC 50 /LD 50 of 66.6 mg L -1 , 117.2 μg larva -1 and 61.4 μg adult -1 , respectively. It was not toxic to non-target Eisenia fetida earthworms and moderately toxic to Daphnia magna microcrustaceans, over the positive control α-cypermethrin. The essential oil cytotoxicity on human keratinocytes and fibroblasts showed high IC 50 values (71.3 and 84.4 μg mL -1 , respectively). Comet assay data highlighted no DNA damages. Based on our findings, this essential oil, characterized by the ascaridole/p-cymene chemotype, could be a candidate for the formulation of botanical insecticides; large-scale production of green insecticides by this rare species may be assured by ex situ cultivation and biotechnological techniques., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

A Musca domestica L. strain collected from Pakistan has recently been shown to be resistant to spinosad; however, there is scarce information about the mechanism of resistance. For this reason, we explored whether a metabolic-based mechanism was responsible by analyzing the activities of the metabolic detoxifying enzymes, carboxylesterases, glutathione S-transferases, and mixed-function oxidases, in both a spinosad-selected (Spin-SEL) strain of M. domestica and a susceptible counterpart (Lab-susceptible). The results revealed that both strains were statistically at par in terms of enzyme activities. The activity of carboxylesterases in the Lab-susceptible strain was 78.17 ± 3.06 in comparison to 79.16 ± 3.31 nmol min-1 mg-1 in the Spin-SEL strain. The activity of mixed-function oxidases was 51.58 ± 4.20 in the Lab-susceptible strain, whereas 54.33 ± 4.08 pmol min-1 mg-1 was recorded in the Spin-SEL strain. The activity of glutathione S-transferases was 86.50 ± 4.59 (Lab-susceptible) and 90.33 ± 2.81 nmol min-1 mg-1 (Spin-SEL). These results revealed that the studied enzymes might not be responsible for spinosad resistance in the studied strain of M. domestica. Therefore, studies should be extended to find out other possible mechanisms of spinosad resistance., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Ethnopharmacological Relevance: The use of Hazomalania voyronii, popularly known as hazomalana, to repel mosquitoes and resist against insect attacks is handed down from generation to generation in Madagascar. In the present study, we investigated the ability of the essential oils (EOs) obtained from the stem wood, fresh and dry bark of H. voyronii to keep important mosquito vectors (Aedes aegypti and Culex quinquefasciatus) away, as well as their toxicity on three insect species of agricultural and public health importance (Cx. quinquefasciatus, Musca domestica and Spodoptera littoralis)., Materials and Methods: Hydrodistillation was used to obtain EOs from stem wood, fresh and dry bark. The chemical compositions were achieved by gas chromatography-mass spectrometry (GC-MS). Toxicity assays using stem wood and bark EOs were performed on larvae of Cx. quinquefasciatus and S. littoralis, and adults of M. domestica by WHO and topical application methods, respectively. Mosquito repellent activity of the most effective EO, i.e. the bark one, was determined on human volunteers by arm-in-cage tests, and results were compared with that of the commercial repellent N,N-ddiethyl-m-toluamide (DEET)., Results: The H. voyronii EOs were characterized by oxygenated monoterpenes with perilla aldehyde (30.9-47.9%) and 1,8-cineole (19.7-33.2%) as the main constituents. The fresh and dry bark EOs were the most active on Cx. quinquefasciatus and S. littoralis larvae, respectively, with LC 50 /LD 50 of 65.5  mg L -1 , and 50.5  μg larva -1 ; the EOs from wood and fresh bark displayed the highest toxicity on M. domestica (LD 50 values 60.8 and 65.8 μg adult -1 , respectively). Repellence assay revealed an almost complete protection (>80%) from both mosquito species for 30 min when pure fresh bark EO was applied on the volunteers' arm, while DEET 10% repelled >80% of the mosquitoes up to 120 min from application., Conclusion: The traditional use of the bark EO to repel insects has been demonstrated although an extended-release formulation based on H. voyronii EOs is needed to increase the repellent effect over time. A wide spectrum of insecticidal activity has been provided as well, suggesting a possible use of H. voyronii EOs in the fabrication of green repellents and insecticides useful to control mosquito vectors and agricultural pests., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Insecticidal usage in the rice farming system may affect non-target insect species present in the same fields. Musca domestica, a well-known pest of medical and veterinary importance worldwide, is one of the important non-target insect species present in the rice farming system. In this study, five strains of M. domestica were exclusively collected from rice fields in major rice cultivated areas of Punjab, Pakistan, and evaluated for the presence of insecticide resistance against nine commonly used insecticides in the rice farming system. Moreover, the performance of life-history traits was also studied. Compared with a Lab-susceptible reference strain of M. domestica, all the field strains exhibited moderate levels of resistance to carbofuran (RRs = 27.96-46.00 fold) and cartap hydrochloride (RRs = 31.48-48.21 fold), low to moderate levels of resistance to gamma-cyhalothrin (RRs = 19.00-43.00 fold), chlorantraniliprole (RRs = 11.90-27.10 fold), monomehypo (RRs = 14.38-25.84 fold), and fipronil (RRs = 13.23-40.15 fold), low levels of resistance to triazophos (RRs = 11.13-19.83 fold), and very low to low levels of resistance (RRs = 7.83-13.28 fold) to flonicamid. The performance of life-history traits (developmental time, adult eclosion rate, fecundity, egg hatch rate, and longevity of adults) of field strains was weaker as compared with that of the Lab-susceptible strain. These results contribute to the growing knowledge on the effects of insecticidal usage in agriculture on non-target invertebrates, and necessitate the need to explore alternate insecticides that can effectively control insect pests but safe for non-target organisms., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Carlina acaulis (Compositae) is traditionally used for food and medicinal purposes in central and southern Europe. Its root essential oil (EO), mainly composed by carlina oxide, is included in the BELFRIT botanical list of food supplements. It is also recognized as a potent mosquito larvicide. It is matter of concern whether this EO could be endowed with intrinsic toxicity to limit its use on a food level. Focusing on the insecticidal activity of this EO, we investigated the acute toxicity and sublethal effects on Musca domestica. In topical assays, the EO was extremely effective (LD 50  = 2.74 and 5.96 μg fly -1 , on males and females, respectively). The exposure to a sublethal dose (LD 30 ) led to significant reductions of female longevity (LT 50  = 6.7-9.0 days vs. control LT 50  = 12.9-13.7 days). Treated females laid 2.5 times fewer eggs over control ones. F 1 vitality decreased: F 1 larvae and pupae showed high mortality, 2-4-fold higher over the control. The EO also showed high cytotoxicity on normal human fibroblasts (NHF-A12, IC 50  = 9.4-14.2 μg mL -1 after 6-48 h). Overall, our findings support the employ of this EO for developing botanical insecticides. At the same time, they encourage food safety authorities to perform a full toxicological assessment for possible restrictions at food level., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Ninety-four putative G protein-coupled receptors (GPCRs) were identified in the Musca domestica genome. They were annotated and compared with their homologues in Drosophila melanogaster. Phylogenetic analyses of the GPCRs from both species revealed that several family members shared a closer relationship based on the domain architecture. The expression profiles of these genes were examined by quantitative real-time PCR amongst three strains of the house fly, a near-isogenic line strain with imidacloprid resistance (N-IRS), the corresponding susceptible strain (CSS) and another strain derived from field populations with imidacloprid resistance (IRS). We found that five GPCR genes were upregulated in the N-IRS and eight GPCR genes were upregulated in the IRS strains compared to the CSS strain. The transgenic lines of D. melanogaster with the GPCR genes (LOC101899380 in the N-IRS strain and LOC101895664 in the IRS strain) exhibited significantly increased tolerance to imidacloprid, and higher expression of cytochrome P450 genes. Bioinformatic analysis of LOC101899380 was carried out based on its full-length nucleic acid sequence and putative amino acid sequence, and it was named Methuselah-like10 (Mthl10) owing to its homology with D. melanogaster Mthl10. A cell-base cell counting kit-8 toxicity assay demonstrated that the expression of the GPCR gene LOC101899380 in Spodoptera frugiperda (Sf9) cells using a baculovirus-mediated expression system can elevate the cell tolerance to imidacloprid, indirectly supporting the hypothesis that the GPCR gene LOC101899380 plays some role in imidacloprid resistance. These results should be useful for furthering understanding of the regulatory pathway by which house flies develop resistance., (© 2019 The Royal Entomological Society.)

Fitness is closely associated with the development of pesticide resistance in insects, which determines the control strategies employed to target species and the risks of toxicity faced by non-target species. After years of selections with beta-cypermethrin in laboratory, a strain of housefly was developed that was 684,521.62-fold resistant (CRR) compared with the susceptible strain (CSS). By constructing ≤ 21 d and ≤ 30 d life tables, the differences in life history parameters between CSS and CRR were analyzed. The total production numbers of all the detected development stages in CRR were lower than in CSS. Except for the lower mortality of larvae, all the other detected mortalities in CRR were higher than in CSS. ♀:♂ and normal females of CRR were also lower than those of CSS. For CRR, the relative fitness was 0.25 in the ≤ 21 d life table and 0.24 in the ≤ 30 d life table, and a lower intrinsic rate of increase (rm) and net reproductive rate (Ro) were detected. Based on phenotype correlation and structural equation model (SEM) analyses, fecundity and viability were the only directly positive fitness components affecting fitness in CRR and CSS, and the other components played indirect roles in fitness. The variations of the relationships among fitness, fecundity and viability seemed to be the core issue resulting in fitness differences between CRR and CSS. The interactions among all the detected fitness components and the mating frequency-time curves appeared to be distinctly different between CRR and CSS. In summary, fecundity and its related factors separately played direct and indirect roles in the fitness costs of a highly beta-cypermethrin-resistant housefly strain., Competing Interests: The authors have declared that no competing interests exist.

Although esterase-mediated spinosad resistance has been proposed for several insects, the associated molecular mechanism remains poorly understood. In this study, we investigated the mechanism of esterase-based spinosad resistance in house flies using a susceptible strain (SSS) and a spinosad-resistant, near-isogenic line (N-SRS). Combined with the synergistic effect of DEF on spinosad in the N-SRS strain, decreased ali-esterase activity in the spinosad-resistant strain has implicated the involvement of mutant esterase in spinosad resistance in house flies. Examination of the carboxylesterase gene MdαE7 in the two strains revealed that four non-synonymous mutations (Trp 251 -Leu, Asp 273 -Glu, Ala 365 -Val, and Ile 396 -Val) may be associated with spinosad resistance in house flies. Single nucleotide polymorphism analysis further indicated a strong relationship between these four mutations and spinosad resistance. Moreover, quantitative real-time PCR revealed a female-linked MdαE7 expression pattern in the N-SRS strain, which may contribute to sex-differential spinosad resistance in house flies.

House flies are global pests and notoriously difficult to control. Essential oils of vetiver, cinnamon, and lavender and their blends were tested for toxic and repellent effects against larval and adult flies. All of the oils had moderate toxicity for eggs. Mortality of 2 nd instar larvae was 57-78% in dipping assays, 38-100% in contact assays, and 94-100% in treated media. Lavender was less effective (38% mortality) than the others (91-100%) in contact bioassays. Oil blends were not more effective against larvae than individual oils. Vetiver and cinnamon oils were strongly repellent (84 and 78%, respectively) for larvae in treated media. None of the oils were repellent for adult house flies in olfactometer assays, but testing of additional products demonstrated significant repellency for neem oil, p-menthane-3,8-diol (PMD), and vanillin. Contact/fumigant toxicity of vetiver, cinnamon, and lavender oils was 100%, significantly higher than mortality from sunflower oil (67%). Blends of oils were not more effective against adults than the individual oils, but blends diluted with sunflower oil were as effective as the individual oils. Essentials oils of vetiver and cinnamon may have potential for fly management in situations where conventional insecticides cannot be used., (© 2019 The Society for Vector Ecology.)

Background: Permethrin (a pyrethroid) has been recommended for the management of a number of insect pests, including Musca domestica. Recently, resistance to permethrin has been reported from the Punjab province, Pakistan, which necessitates the need to manage the resistance problem. For this reason, a field strain of M. domestica was selected with permethrin for ten consecutive generations (G1-G10) to determine the risk assessment, the rapidity with which permethrin resistance can develop, and the presence or absence of the cross-resistance phenomenon., Results: The results revealed that permethrin resistance increased very quickly in response to selection experiments. The resistance ratio (RR) value increased by 16.04- to 605.92-fold and the LD 50 value increased by 100.22 to 3787.08 ng fly -1 after selection experiments. Moreover, the increase in LD 50 value remained stable when the selected strain (Perm-SEL) was cultured in the absence of permethrin for the next five generations (G11-G15). The results revealed the possibility of minor cross-resistance in the Perm-SEL strain with β-cyfluthrin and deltamethrin, and lack of cross-resistance with imidacloprid and spinosad. The realized heritability (h 2 ) value for the Perm-SEL strain was 0.23. Assuming a mean slope value of 1.27 and an h 2 value of 0.23, then ten to four generations would be estimated for a 10-fold increase in the LD 50 values at 50-90% selection intensity, respectively., Conclusion: The results of present study revealed high risk for permethrin resistance development under continuous selection pressure. Permethrin resistance developed very quickly under laboratory conditions, which might reflect the likelihood of resistance evolution in field conditions if permethrin selection pressure holds for a long time. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)

The toxicity of Origanum vulgare essential oil to the housefly Musca domestica L. was evaluated. The major constituents of the O. vulgare essential oil by gas chromatographic mass spectrometry (GC-MS) analysis were carvacrol (58.13%), p-cymene (17.85%), thymol (8.15%), γ-terpinene (4.96%), and linalool (3.69%). Toxicity of O. vulgare essential oil against larvae and pupae was evaluated using fumigation and contact assays. The contact toxicity (LC 50 ) of O. vulgare essential oil and carvacrol for larvae was 0.23 and 0.03 μL/cm 2 , respectively. The fumigation toxicity (LC 50 ) of O. vulgare essential oil and carvacrol for larvae was 9.52 and 2.78 μL/L, respectively. Pupal toxicity was evaluated by percentage inhibition rate (PIR). PIR of O. vulgare essential oil at 0.25 μL/cm 2 was 90.9% for the contact assay and 100% at 20 μL/L for the fumigation assay. PIR of carvacrol was 29.5% (0.025 μL/cm 2 ) and 81.8% (1.25 μL/L) for the contact toxicity and fumigation assay, respectively. O. vulgare essential oil and carvacrol have significant toxicity to the housefly and are potential insecticides for housefly control.

Introduction: Musca domestica is resistant to many insecticides; hence, biological control is a suitable alternative., Methods: We evaluated the lethality of strain Btk176 towards the larval and adult M. domestica and the histopathological effects in the larvae midgut., Results: We observed 99% larval and 78.9% adult mortality within 48 hours of spore ingestion (dosage, 2.4×108 CFU/ml). The histopathological effects were consistent with cytotoxicity. PCR analysis showed the presence of the cry1Ba gene. Transmission electron microscopy revealed a bipyramidal parasporal body. Thurigiensin activity was not detected., Conclusions: The serovar, Btk176 might be a potential biocontrol agent for houseflies.

Insecticide resistance in house fly populations is a major problem faced by livestock producers worldwide. A survey of insecticide resistance levels and pyrethroid resistance allele frequencies in the United States was conducted in 2008-09, but little is known about how resistance levels have changed over the last 10 years. In addition, new target-site pyrethroid resistance alleles that confer high levels of resistance have been recently identified in the voltage-sensitive sodium channel, and their frequencies in field populations are unknown. Our aim in this study was to reassess the resistance status of house flies from select locations in the United States by examining resistance levels against commonly used insecticides and frequencies of known resistance alleles. House flies were collected from animal production facilities in five different states between 2016 and 2018. Resistance levels to three insecticides (permethrin, tetrachlorvinphos, and methomyl), representing three classes of insecticides (pyrethroids, organophosphates and carbamates) varied geographically and were lowest in the population collected from New Mexico, intermediate in the population collected from Utah, and greatest in the population from Kansas. The recently identified 1B pyrethroid resistance allele increased dramatically in frequency compared to previous reports, most notably in populations from Kansas and Maryland, indicating that it may already be widespread around the United States. Based on comparison with historical data, the population collected from Kansas represents one of the most highly permethrin resistant populations ever sampled. If the alleles responsible for this level of resistance spread, pyrethroids may be of limited use for house fly control in the United States in the near future., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Females developed notably higher resistance than males in a spinosad-resistant house fly strain, however, resistance factors responsible for this phenomenon are poorly understood. In this study, the potential role of cytochrome P450 monooxygenases involved in the sex-differential spinosad resistance in house flies was investigated, using a susceptible strain (SSS) and a spinosad resistant near-isogenic line (N-SRS). Combination of the synergism of spinosad by PBO and increased cytochrome P450 monooxygenase activity in the N-SRS strain implied that cytochrome P450 monooxygenases contributed to spinosad resistance in house flies. Transcriptional levels of eight P450 genes related to insecticide resistance in two genders of the SSS and N-SRS strain were separately evaluated by quantitative real-time PCR. Notably, compared with the corresponding gender of susceptible SSS house flies, CYP4G2 and CYP6A5v2 were overexpressed in resistant N-SRS females, while the expression of these two P450 genes was significantly decreased in resistant N-SRS males. Furthermore, by measuring the expression of CYP4G2 and CYP6A5v2 in female and male house fly populations with different spinosad resistance levels, which were generated from a series of genetic crosses, the genetic linkage between spinosad resistance and P450 gene expression was analyzed. It was found that with increased spinosad resistance, CYP4G2 and CYP6A5v2 were up-regulated in females, while both of them were down-regulated in males, and this suggested their involvement in the female-linked spinosad resistance of house flies. Taken together, our results provide valuable insight into the involvement of cytochrome P450 monooxygenases in the sex-differential spinosad resistance in house flies., (Copyright © 2019. Published by Elsevier Inc.)

In this work, we evaluated the ovicidal activity and the deleterious effects of cashew (Anacardium occidentale) nut shell oil and its fractions on the development of Musca domestica and Chrysomya megacephala, important vectors of several diseases. The insecticidal effects of this plant were also measured on the first and second instar larvae of Anticarsia gemmatalis and Spodoptera frugiperda, soy and maize pests, respectively. The fly eggs and the crop pest insect larvae were exposed to the cashew (Anacardium occidentale) nut shell liquid (CNSL) and its fractions: technical CNSL, anacardic acid, cardanol and cardol. The results show that the cardol fraction, for both species of flies, presented the lowest lethal concentration with LC 50 of 80.4 mg/L for M. domestica and 90.2 mg/L for C. megacephala. For the mortality of the larvae of A. gemmatalis and S. frugiperda, the most effective fraction was anacardic acid with LC 50 of 295.1 mg/L and 318.4 mg/L, respectively. In all species, the mortality rate of the commercial compounds (cypermethrin 600 mg/L and temephos 2 mg/L) was higher than that of the evaluated compounds. Despite this, the results obtained suggest their potential in field trials, once the fractions of A. occidentale presented high mortality at low lethal concentrations in laboratory conditions, with the possibility of integrated use in the control of disease vectors and agricultural pests, employing ecofriendly compounds., (© 2019 Wiley-VHCA AG, Zurich, Switzerland.)

In this study, two endophytic actinomycetes isolates Oc-5 and Acv-11, were isolated from healthy leaves of medicinal plant Oxalis corniculata L. These isolates were identified as Streptomyces zaomyceticus Oc-5 and Streptomyces pseudogriseolus Acv-11 using 16S rRNA gene sequence. Biomass extract of these strains were used as a greener attempt for synthesis of copper oxide nanoparticles (CuO-NPs). The synthesized NPs were characterized by UV-Vis spectroscopy, Fourier transform infra-red (FT-IR) spectroscopy, X-ray diffraction (XRD)' transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS). Green synthesized NPs showed surface plasmon resonance (SPR) absorption band at 400 nm, crystalline nature, spherical-shaped with an average size of 78 nm and 80.0 nm for CuO-NPs synthesized using strain Oc-5 and Acv-11, respectively. The bioactivities of CuO-NPs were evaluated. Results revealed that CuO-NPs exhibited promising antimicrobial activity against prokaryotic and eukaryotic microbial cells (Gram positive bacteria, Gram negative bacteria, unicellular and multicellular fungi). In addition, it showed antimicrobial potential against phyto-pathogenic fungal strains Fusarium oxysporum, Pythium ultimum, Aspergillus niger and Alternaria alternata. We further explored the in vitro antioxidant activity and cytotoxicity for biosynthesized CuO-NPs. The results revealed that' scavenging and total antioxidant activity for NPs synthesized using Streptomyces pseudogriseolus Acv-11 was better than those synthesized by Streptomyces zaomyceticus Oc-5. Also, the morphological changes and cell viability for Vero and Caco-2 cell line due to NPs treatments were assessed using MTT assay method. Furthermore, Larvicidal efficacy against Musca domestica and Culex pipiens was evaluated. The results obtained in this study clearly showed that biosynthesized CuO-NPs exhibited effective bioactivity and, therefore, provide a base for the development of versatile biotechnological applications soon.