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J.w. Knight - One of the best experts on this subject based on the ideXlab platform.
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Cytochemical localization of lectin-binding to intracellularly melanized first stage larvae of Brugia malayi (Buckley) (Nematoda: Filarioidea) in Anopheles Quadrimaculatus (Say) (Diptera: Culicidae)
International Journal of Insect Morphology and Embryology, 1996Co-Authors: Jai K. Nayar, J.w. KnightAbstract:Abstract Cytochemical localization of Concanavalin A (Con A) lectin followed by gold-labeled horseradish peroxidase binding to carbohydrate moieties on intracellularly developing normal and melanized first stage (L 1 ) larvae of Brugia malayi (Nematoda: Filarioidea) was investigated in the thoracic muscles of Anopheles Quadrimaculatus (Diptera: Culicidae) females. Con A did not bind to the carbohydrate moieties on the larval cuticle or in tissues around the normally developing L 1 , but bound moderately to the carbohydrate moieties in the cellular matrix of the larva. It bound intensely to the carbohydrate moieties of the dense cytoplasmic material and melanin deposits in the melanized capsule surrounding the melanized L 1 . The results suggest that the dense cytoplasmic material in the melanized capsule surrounding the L 1 contains materials with exposed carbohydrate moieties specific for Con A.
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wounding increases intracellular encapsulation melanization of developing brugia malayi nematoda filarioidea larvae in thoracic muscles of Anopheles Quadrimaculatus
Comparative Biochemistry and Physiology Part A: Physiology, 1995Co-Authors: J K Nayar, J.w. KnightAbstract:Wounding of females of the refractory strain of Brugia malayi-infected Anopheles Quadrimaculatus by an injection of saline solution resulted in a significant increase in encapsulation and melanization of intracellularly located first stage (L1) larvae of B. malayi in their thoracic muscles 24 and 48 hr after the injection, when compared to uninjected infected females. This increased encapsulation and melanization response was inhibited by injecting saline solution containing prophenoloxidase and phenoloxidase inhibitors and competitors (benzamidine HCl, p-nitrophenyl-p′guanidinobenzoate HCl, soybean trypsin inhibitor, diethyldithiocarbamic acid-sodium salt, 1-phenyl-2-thiourea, and reduced glutathione) into B. malayi-infected An. Quadrimaculatus females. These results demonstrate for the first time that wounding of the cuticle by injecting saline solution into the hemocoel of the infected females activated the prophenoloxidase cascade that increased encapsulation and melanization of intracellularly located L1 of B. malayi in infected thoracic muscles of An. Quadrimaculatus.
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comparison of migration and encapsulation of brugia malayi microfilariae from the midgut to the hemocoel between Anopheles Quadrimaculatus and aedes aegypti
Journal of Invertebrate Pathology, 1995Co-Authors: J K Nayar, J.w. KnightAbstract:Abstract Comparisons were made of migration and encapsulation of ingested sheathed microfilariae of Brugia malayi from the midgut into the hemocoel between Anopheles Quadrimaculatus (refractory and susceptible strains to B. malayi) and Aedes aegypti (Black-eyed, Liverpool strain susceptible to B. malayi). Encapsulation and melanization of microfilarial sheaths and microfilariae occurred in both strains of An. Quadrimaculatus and in Ae. aegypti . In both strains of An. Quadrimaculatus, by 4 hr and by 24 hr after the ingestion of sheathed microfilariae of B. malayi in the infected bloodmeal, significantly more sheathed microfilariae penetrated the midgut and reached the hemocoel and thoracic muscles compared with those in Ae. aegypti . During the same time periods significantly more encapsulated and melanized microfilarial sheaths and a larger percentage of encapsulated and melanized microfilariae were observed in the hemocoel of both strains of An. Quadrimaculatus than in Ae. aegypti. The results suggest that differences observed in the numbers of encapsulated and melanized microfilarial sheaths and percentages of melanized microfilariae between An. Quadrimaculatus (both strains) and Ae. aegypti are due to different rates of penetration of the sheathed microfilariae from the midgut to the hemocoel.
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Ultrastructure of the intracellular melanization of Brugia malayi (Buckley) (Nematoda : Filarioidea) in the thoracic muscles of Anopheles Quadrimaculatus (Say) (Diptera : Culicidae)
International Journal of Insect Morphology and Embryology, 1995Co-Authors: Marta L. Chikilian, Jai K. Nayar, Timothy J. Bradley, Cora E. Cash-clark, J.w. KnightAbstract:Ultrastructural details of the melanization of the filarial parasite Brugia malayi (Nematoda : Filarioidea) in the thoracic muscle cell of selected susceptible and refractory strains of Anopheles Quadrimaculatus (Diptera : Culicidae) were examined. In both susceptible and refractory strains, following infection of the muscle cells, there is a dissolution of the sarcoplasmic cytoskeletal matrix surrounding the myofibrils, causing the myofibrils and mitochondria to drift apart and lose their regular spacing. This is coupled with a reorganization of the cytoplasm near the normally developing intracellular larva. Masses of vesicles and vesiculated cytoplasmic bodies accumulate near the larva. Eventually, these form a dense layer of cytoplasm around the parasite. Fine grains of melanin begin to appear in this dense cytoplasmic layer, increasing gradually until a nearly complete capsule of melanin surrounds the larva. The time course of melanization was found to be quite variable among and even within mosquitoes. Strains of A. Quadrimaculatus selected to be refractory or susceptible to B. malayi, were found to vary substantially in the frequency of intracellular melanization, but not in the mechanism.
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Ultrastructural comparison of extracellular and intracellular encapsulation of Brugia malayi in Anopheles Quadrimaculatus.
The Journal of parasitology, 1994Co-Authors: Marta L. Chikilian, Jai K. Nayar, Timothy J. Bradley, J.w. KnightAbstract:Ultrastructural aspects of extracellular humoral encapsulation of microfilariae of Brugia malayi in the hemocoel of Anopheles Quadrimaculatus were compared with those of intracellular encapsulation of first-stage larvae (L1) of the same parasite species, in the thoracic muscle cells of the same species of mosquito. The results showed that extracellular humoral encapsulation of microfilarial sheaths, and sheathed and exsheathed microfilariae, in the hemocoel of mosquitoes occurs around the parasite within the first 6 hr postingestion, apparently without initial participation of hemocytes. Hemocytes and their remnants were observed near the parasite during the first 6 hr postingestion. Within the next 24 hr, hemocytes attach to the initial humoral capsule. By contrast, intracellular encapsulation of L1S is initiated by the accumulation of a dense cytoplasmic layer derived from the infected thoracic muscle cell. Melanin deposits accumulate in this layer adjacent to the parasite cuticle, again without visible participation of hemocytes.
Phillip E. Kaufman - One of the best experts on this subject based on the ideXlab platform.
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vapor toxicity of five volatile pyrethroids against aedes aegypti aedes albopictus culex quinquefasciatus and Anopheles Quadrimaculatus diptera culicidae
Pest Management Science, 2018Co-Authors: Christopher S Bibbs, Ulrich R Bernier, Ruide Xue, Maia Tsikolia, Jeffrey R Bloomquist, Phillip E. KaufmanAbstract:BACKGROUND Mosquito mortality has been documented in numerous studies of spatial repellents but the concentration-dependent toxicity of spatial repellent vapors has not been documented. To address this issue, prallethrin, flumethrin, metofluthrin, transfluthrin, and meperfluthrin were selected for comparative study against Aedes albopictus (Skuse), Ae. aegypti (L.), Culex quinquefasciatus Say, and Anopheles Quadrimaculatus Say. Mosquito were exposed to vapors of each chemical for 2, 4, and 24 h with mortality recorded at each time point. A second experiment involved exposing mosquitoes to vapors for 2 h, then transferring them to untreated holding containers and held for 24 h. For these mosquitoes, readings were only taken after 24 h to allow for metabolic detoxification and recovery. RESULTS LC50 and LC90 data indicated that transfluthrin and meperfluthrin had the greatest toxicity across all species, followed by metofluthrin, prallethrin, and flumethrin. CONCLUSION Our findings, through the direct comparison of these compounds, suggest that transfluthrin, meperfluthrin, and metofluthrin be considered for further development. The vapor toxicity for the aforementioned compounds significantly exceeds prallethrin, which is currently market available as an adulticidal active ingredient in public health pest control. © 2018 Society of Chemical Industry.
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Evaluation of semiochemical toxicity to Aedes aegypti, Ae. albopictus and Anopheles Quadrimaculatus (Diptera: Culicidae).
Pest management science, 2010Co-Authors: Phillip E. Kaufman, Rajinder S. Mann, Jerry F. ButlerAbstract:BACKGROUND: Mosquitoes are the most important vectors of human pathogens. Wide-scale use of pesticides has led to the development of resistance to most common insecticide groups. The need to develop novel products that have a low impact on human health and the environment is well established. The toxicity of selected semiochemicals with molecular structures indicative of insecticidal activity was determined against adult Aedes aegypti (L.) and Anopheles Quadrimaculatus (Say). The two most active insecticides against Ae. aegypti were also evaluated against Ae. albopictus (Skuse). RESULTS: Fifteen semiochemicals classified as terpenoid alcohols, ketones or carboxylic esters showed toxicity to both mosquito species. Geranyl acetone (LC50 = 38.51 µg cm−2) followed by citronellol (LC50 = 48.55 µg cm−2) were the most toxic compounds to Ae. aegypti, while geraniol and lavonax, with LC50 values of 31.88 and 43.40 µg cm−2, showed the highest toxicity to An. Quadrimaculatus. Both geranyl acetone and citronellol were highly toxic to Ae. albopioctus. No semiochemical showed fumigation activity against either species. All semiochemicals persisted for less than 24 h when tested on filter paper. CONCLUSION: Quantification of LC50 values of several semiochemicals against Ae. Aegypti, An. Quadrimaculatus and Ae. albopioctus showed that semiochemicals not only modify insect behaviors but also hold potential as potent insecticides for mosquito control programs. Copyright © 2010 Society of Chemical Industry
J K Nayar - One of the best experts on this subject based on the ideXlab platform.
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wounding increases intracellular encapsulation melanization of developing brugia malayi nematoda filarioidea larvae in thoracic muscles of Anopheles Quadrimaculatus
Comparative Biochemistry and Physiology Part A: Physiology, 1995Co-Authors: J K Nayar, J.w. KnightAbstract:Wounding of females of the refractory strain of Brugia malayi-infected Anopheles Quadrimaculatus by an injection of saline solution resulted in a significant increase in encapsulation and melanization of intracellularly located first stage (L1) larvae of B. malayi in their thoracic muscles 24 and 48 hr after the injection, when compared to uninjected infected females. This increased encapsulation and melanization response was inhibited by injecting saline solution containing prophenoloxidase and phenoloxidase inhibitors and competitors (benzamidine HCl, p-nitrophenyl-p′guanidinobenzoate HCl, soybean trypsin inhibitor, diethyldithiocarbamic acid-sodium salt, 1-phenyl-2-thiourea, and reduced glutathione) into B. malayi-infected An. Quadrimaculatus females. These results demonstrate for the first time that wounding of the cuticle by injecting saline solution into the hemocoel of the infected females activated the prophenoloxidase cascade that increased encapsulation and melanization of intracellularly located L1 of B. malayi in infected thoracic muscles of An. Quadrimaculatus.
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comparison of migration and encapsulation of brugia malayi microfilariae from the midgut to the hemocoel between Anopheles Quadrimaculatus and aedes aegypti
Journal of Invertebrate Pathology, 1995Co-Authors: J K Nayar, J.w. KnightAbstract:Abstract Comparisons were made of migration and encapsulation of ingested sheathed microfilariae of Brugia malayi from the midgut into the hemocoel between Anopheles Quadrimaculatus (refractory and susceptible strains to B. malayi) and Aedes aegypti (Black-eyed, Liverpool strain susceptible to B. malayi). Encapsulation and melanization of microfilarial sheaths and microfilariae occurred in both strains of An. Quadrimaculatus and in Ae. aegypti . In both strains of An. Quadrimaculatus, by 4 hr and by 24 hr after the ingestion of sheathed microfilariae of B. malayi in the infected bloodmeal, significantly more sheathed microfilariae penetrated the midgut and reached the hemocoel and thoracic muscles compared with those in Ae. aegypti . During the same time periods significantly more encapsulated and melanized microfilarial sheaths and a larger percentage of encapsulated and melanized microfilariae were observed in the hemocoel of both strains of An. Quadrimaculatus than in Ae. aegypti. The results suggest that differences observed in the numbers of encapsulated and melanized microfilarial sheaths and percentages of melanized microfilariae between An. Quadrimaculatus (both strains) and Ae. aegypti are due to different rates of penetration of the sheathed microfilariae from the midgut to the hemocoel.
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comparative study of hemolymph phenoloxidase activity in aedes aegypti and Anopheles Quadrimaculatus and its role in encapsulation of brugia malayi microfilariae
Comparative Biochemistry and Physiology Part A: Physiology, 1994Co-Authors: J K Nayar, T J BradleyAbstract:Abstract Hemolymph phenoloxidase activity of sugar-fed and blood-fed females of Anopheles Quadrimaculatus and Aedes aegypti showed similar characteristics. Phenoloxidase was present as an inactive proenzyme in both mosquito species and was partially activated during collection of the hemolymph. In both mosquito species, phenoloxidase activity was modulated by different buffers and activated phenoloxidase did not need Ca 2+ . Enzymatic activity was higher in the hemocytes than in the plasma in both mosquito species. Trypsin, laminarin, and blood-feeding on uninfected and Brugia malayi -infected jirds enhanced hemolymph phenoloxidase activity in both mosquito species. The appearance of hemolymph phenoloxidase activity was inhibited by p -nitrophenyl p ′-guanidinobenzoate HCl, soybean trypsin inhibitor, ethylenediaminetetraacetic acid, diethyldithiocarbamic acid, saturated 1-phenyl-2-thiourea and reduced glutathione, but not by benzamidine in A. Quadrimaculatus . The appearance of hemolymph phenoloxidase activity was inhibited by benzamidine, diethyldithiocarbamic acid, saturated 1-phenyl-2-thiourea, reduced glutathione, β-nitrophenyl p ′-guanidinobenzoate and soybean trypsin inhibitor, but not by ethylenediaminetetraacetic acid in A. aegypti . It is suggested that in both mosquito species, blood-feeding and migration of sheathed microfilariae in the homocoel activated the prophenoloxidase in the hemolymph and caused the encapsulation and melanization of microfilarial sheaths and microfilariae of B. malayi .
Kenneth J Linthicum - One of the best experts on this subject based on the ideXlab platform.
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susceptibility of aedes aegypti culex quinquefasciatus say and Anopheles Quadrimaculatus say to 19 pesticides with different modes of action
Journal of Medical Entomology, 2008Co-Authors: Julia W Pridgeon, Roberto M Pereira, James J Becnel, Gary G Clark, Sandra A. Allan, Kenneth J LinthicumAbstract:Abstract To access the relative potency of pesticides to control adult mosquitoes, 19 pesticides with various modes of action were evaluated against Aedes aegypti, Culex quinquefasciatus Say, and Anopheles Quadrimaculatus Say. On the basis of 24-h LD50 values after topical application, the only pesticide that had higher activity than permethrin was fipronil, with LD50 values lower than permethrin for 107-, 4,849-, and 2-fold against Ae. aegypti, Cx. quinquefasciatus Say, and An. Quadrimaculatus Say, respectively. Abamectin, imidacloprid, spinosad, diazinon, and carbaryl showed slightly lower activity than permethrin ( 1000-fold. On the basis of 24-h LD50 values, Cx. quinquefasciatus was the least susceptible species to nine pesticides tested (DNOC, azocyclotin, chlorfenapyr, carbaryl, spinosad, imidacloprid, diazinon, abamectin, and permethrin), whereas Ae. aegypti...
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susceptibility of aedes aegypti culex quinquefasciatus say and Anopheles Quadrimaculatus say to 19 pesticides with different modes of action
Journal of Medical Entomology, 2008Co-Authors: Julia W Pridgeon, Roberto M Pereira, James J Becnel, Gary G Clark, Sandra A. Allan, Kenneth J LinthicumAbstract:To access the relative potency of pesticides to control adult mosquitoes, 19 pesticides with various modes of action were evaluated against Aedes aegypti, Culex quinquefasciatus Say, and Anopheles Quadrimaculatus Say. On the basis of 24-h LD50 values after topical application, the only pesticide that had higher activity than permethrin was fipronil, with LD50 values lower than permethrin for 107-, 4,849-, and 2-fold against Ae. aegypti, Cx. quinquefasciatus Say, and An. Quadrimaculatus Say, respectively. Abamectin, imidacloprid, spinosad, diazinon, and carbaryl showed slightly lower activity than permethrin ( 1000-fold. On the basis of 24-h LD50 values, Cx. quinquefasciatus was the least susceptible species to nine pesticides tested (DNOC, azocyclotin, chlorfenapyr, carbaryl, spinosad, imidaclorid, diazinon, abamectin, and permethrin) , whereas Ae. aegypti was the least susceptible species to six pesticides tested (dicofol, amitraz, propargite, hydramethylnon, cyhexatin, and diafenthiuron), and An. Quadrimaculatus was the least susceptible species to four pesticides tested (bifenazate, pyridaben, indoxacarb, and fipronil). Our results revealed that different species of mosquitoes had different susceptibility to pesticides, showing the need to select the most efficacious compounds for the least susceptible mosquito species to achieve successful mosquito control.
M V Meisch - One of the best experts on this subject based on the ideXlab platform.
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riceland mosquito management practices for Anopheles Quadrimaculatus larvae
Journal of The American Mosquito Control Association, 2008Co-Authors: R A Allen, W W Wilkes, C N Lewis, M V MeischAbstract:ABSTRACT Two separate but related studies were conducted regarding management of Anopheles Quadrimaculatus larval populations in commercial rice fields near Cleveland, MS, in 2004. Study 1 was to evaluate the effectiveness of 2 treatments of aerially applied ultra-low volume applications of Bacillus thuringiensis var. israelensis (Bti) against An. Quadrimaculatus larvae in dense, high-canopy mid- to late-season rice crop. Study 2 was to investigate the effect of preflood treatments of lambda-cyhalothrin (Karate®), which is commonly used against rice water weevil (Lissorhoptrus oryzophilus), on An. Quadrimaculatus larvae. Excellent initial, but short residual control (>99% control 1 day after treatment) was observed in the Bti-treated fields in both mid- and late-season rice. Little or no effect on mosquito larvae was observed in the lambda-cyhalothrin–treated fields. Results indicate that Bti can be effectively used by mosquito management personnel to control larval populations of An. Quadrimaculatus in l...
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comparison of dilute and neat formulations of anvil by ultra low volume ground application against Anopheles Quadrimaculatus in arkansas
Journal of The American Mosquito Control Association, 2007Co-Authors: M V Meisch, David A Dame, C N LewisAbstract:ABSTRACT Neat (undiluted) and diluted ground-applied ultra-low volume (ULV) cold aerosol formulations of sumithrin (Anvil®) were evaluated against Anopheles Quadrimaculatus adults. Both formulations were applied at 1.938 g/AI/ha (0.00173 lb/AI/acre). Caged sentinel mosquitoes were placed on 1.5-m stakes 30.4, 60.9, and 91.0 m downwind and perpendicular to the line of spray. Mortality was observed at 1, 12, and 24 h posttreatment. Except for 1-h readings at 30.4 and 91.0 m the neat formulation was significantly more effective than the dilute. Droplet size and density averaged 13.6 µm and 422/cm2 for dilute formulation and 14.3 µm and 251/cm2 for the neat. There was no apparent relationship between droplet size and density when compared with mosquito mortality.
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aerial ultra low volume assessment of anvil 10 10 against Anopheles Quadrimaculatus
Journal of The American Mosquito Control Association, 2005Co-Authors: M V Meisch, David A Dame, James R BrownAbstract:ABSTRACT Against caged field-collected adults of Anopheles Quadrimaculatus, optimized aerial applications of ANVIL 10+10®at 18.4 ml (1.63 g active ingredient)/0.4 ha produced a mean mortality of 92% at 1, 12, and 24 h after treatment. These trials were conducted with 7 stacked passes applied 1,067 m upwind of the target site when wind velocity was 18–21 km/h at an application altitude of 46 m and 5–10 km/h at ground level. When the wind velocity aloft was greater than might be operationally acceptable (27 km/h), reduced efficacy (64% mortality) was observed in the bioassay site (1,524 m downwind from 11 stacked passes) in an unreplicated application. Droplets from the 2 tail-mounted Beecomist 360-A-12-V rotary atomizers (fitted with wire sleeve cages of size 40 mesh) collected on spinning Teflon®-coated slides in the target area averaged a volume mean diameter (VMD) of 29 μm and a droplet density of 39 droplets/cm2 in 18- to 21-km/h winds. With 27-km/h winds aloft and a greater application offset, the VMD...
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efficacy of biomist 30 30 and aqua reslin against Anopheles Quadrimaculatus in arkansas
Journal of The American Mosquito Control Association, 2002Co-Authors: R J Crockett, J A Dennett, C M Ham, R D Nunez, M V MeischAbstract:Aqua Reslin and Biomist 30:30 technical permethrin and piperonyl butoxide were applied via ground ultra-low volume at a rate of 237 ml/min and 0.00196 kg active ingredient/ha against wild-caught adult Anopheles Quadrimaculatus. The 2 formulations did not differ significantly at 31 m from the spray path (P < or = 0.05). However, at 61 and 91 m, percent mortality for 30:30 was significantly higher than for Aqua Reslin at each time after treatment (P < or = 0.05). Between 12 and 24 h, about 8% recovery was observed in mosquitoes treated with Aqua Reslin at 31 m.
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a simple technique for rapid colonization of Anopheles Quadrimaculatus using adults aspirated from livestock barns
Journal of The American Mosquito Control Association, 2000Co-Authors: James A Dennett, M V MeischAbstract:A technique was developed for rapid colonization of Anopheles Quadrimaculatus larvae in an improvised insectary using blood-fed mosquitoes aspirated from livestock barns. A novel device termed the mosquito aspiration transfer and ovipositional chamber (MATOC) is described. In 2 field seasons, 14 broods were successfully mass reared, yielding more than 28,500 vigorous 3rd- and 4th-stage larvae used in rice plot and other bioassays. Crowding the females over a natural ovipositional substrate induced oviposition as early as 12 h from introduction into the MATOCs.