Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| a phylogenetic approach to following west nile virus in connecticut. | the 1999 outbreak of west nile (wn) virus in the northeastern united states was the first known natural occurrence of this flavivirus in the western hemisphere. in 1999 and 2000, 82 independent connecticut wn virus isolates were cultured from nine species of birds, five species of mosquitoes, and one striped skunk. nucleotide sequences obtained from these isolates identified 30 genetic changes, compared with wn-ny99, in a 921-nt region of the viral genome beginning at nucleotide position 205 and ... | 2001 | 11606791 |
| aromatic plants in bird nests as a protection against blood-sucking flying insects? | the nest protection hypothesis suggests that some of the fresh plant material, brought by some bird species to their nests, contain secondary compounds that repel parasites or mask the chemical cues that parasites use to find the host. corsican blue tits (parus caeruleus) bring pieces of several species of aromatic plants to the nest at dusk, suggesting a protection against nocturnal agents such as blood-sucking flying insects. the potential repellent or masking effect of these aromatic plant sp ... | 2001 | 11672937 |
| immunization of mice against west nile virus with recombinant envelope protein. | west nile (wn) virus is a mosquito-borne flavivirus that emerged in the united states in 1999 and can cause fatal encephalitis. envelope (e) protein cdna from a wn virus isolate recovered from culex pipiens in connecticut was expressed in escherichia coli. the recombinant e protein was purified and used as ag in immunoblot assays and immunization experiments. patients with wn virus infection had abs that recognized the recombinant e protein. c3h/hen mice immunized with e protein developed e prot ... | 2001 | 11673542 |
| various levels of cross-resistance to bacillus sphaericus strains in culex pipiens (diptera: culicidae) colonies resistant to b. sphaericus strain 2362. | we studied the cross-resistance to three highly toxic bacillus sphaericus strains, iab-59 (serotype h6), iab-881 (serotype h3), and iab-872 (serotype h48), of four colonies of the culex pipiens complex resistant to b. sphaericus 2362 and 1593, both of which are serotype h5a5b strains. two field-selected highly resistant colonies originating from india (kochi, 17,000-fold resistance) and france (sphae, 23,000-fold resistance) and a highly resistant laboratory-selected colony from california (geor ... | 2001 | 11679325 |
| isolation and characterization of a bacillus thuringiensis ssp. kurstaki strain toxic to spodoptera exigua and culex pipiens. | a strain of bacillus thuringiensis with dual toxicity was isolated from korean soil samples and named k2. k2 was determined as ssp. kurstaki (h3a3b3c) by serological test and produced bipyramidal-shaped parasporal inclusions. the plasmid and protein profiles of b. thuringiensis k2 were different from those of the reference strain, ssp. kurstaki hd-1. to verify gene type of b. thuringiensis k2, pcr analysis with specific cry gene primers was performed. the result showed that b. thuringiensis k2 h ... | 2001 | 11683364 |
| invasions by insect vectors of human disease. | nonindigenous vectors that arrive, establish, and spread in new areas have fomented throughout recorded history epidemics of human diseases such as malaria, yellow fever, typhus, and plague. although some vagile vectors, such as adults of black flies, biting midges, and tsetse flies, have dispersed into new habitats by flight or wind, human-aided transport is responsible for the arrival and spread of most invasive vectors, such as anthropophilic fleas, lice, kissing bugs, and mosquitoes. from th ... | 2002 | 11729075 |
| dissecting the cost of insecticide resistance genes during the overwintering period of the mosquito culex pipiens. | in several insects, there appears to be a high fitness cost associated with insecticide resistance genes during the overwintering period. in order to understand when and how this cost operates, all mosquitoes entering a natural cave for overwintering were regularly sampled, and their resistance genes at two loci (ester and ace.1) were individually identified. during the main period of entry (october and november), susceptible mosquitoes were first observed, followed by resistant ones, this trend ... | 2001 | 11737292 |
| using a dynamic hydrology model to predict mosquito abundances in flood and swamp water. | we modeled surface wetness at high resolution, using a dynamic hydrology model, to predict flood and swamp water mosquito abundances. historical meteorologic data, as well as topographic, soil, and vegetation data, were used to model surface wetness and identify potential fresh and swamp water breeding habitats in two northern new jersey watersheds. surface wetness was positively associated with the subsequent abundance of the dominant floodwater mosquito species, aedes vexans, and the swamp wat ... | 2002 | 11749741 |
| efficacy of interferon alpha-2b and ribavirin against west nile virus in vitro. | 2002 | 11749765 | |
| characterization of human ige and mouse igg1 responses to allergens in three mosquito species by immunoblotting and elisa. | ige-mediated allergic reactions caused by mosquito bites are a common problem all over the world. this study was undertaken to determine ige levels in subjects, to elucidate human ige and mouse igg1 binding patterns and to investigate the cross-reactivity of salivary gland antigens with three mosquitoes. | 2001 | 11752877 |
| tissue localization of overproduced esterases in the mosquito culex pipiens (diptera: culicidae). | we have investigated the tissue distribution of overproduced esterases a (a1 and a2) and b (b1 and b2) in strains of culex pipiens l. by immunocytochemistry. s-lab mosquitoes, lacking overproduced esterases, were used as reference. tissues showing a strong specific reaction (fluorescence) were observed with anti-esterase a1 antiserum in s54 (with a1) and bouake (with a2) strains, and with anti-esterase b1 antiserum in tem-r and edit (with b1) and bouake (with b2) strains. overproduction of ester ... | 2001 | 11761376 |
| effect of midgut bacteria of culex pipiens l. on digestion and reproduction. | an investigation was carried out to evaluate the influence of symbiotic bacteria associated with culex pipiens l. on pre-oviposition and blood meal digestion periods, and reproductive potential (fecundity and fertility). aposymbiotic females were obtained by feeding the normal females on 10% sucrose solution mixed with antibiotic (tarivid) for three days before feeding them on normal blood meals from a pigeon host. a total of 4 genera were previously isolated from the midgut of c. pipiens. these ... | 2001 | 11775103 |
| studies on the molluscicidal and larvicidal properties of solanum nigrum l. leaves ethanol extract. | toxicological studies on three ethanol extract preparations of solanum nigrum l. leaves were made on biomphalaria alexandrina. extract (a), made by soaking leaves powder over night in cold 70% ethanol, has the highest activity, (lc50 3.37 mg/l within 24 hr). this extract also showed larvicidal activity against larvae of two mosquito species, aedes caspius and culex pipiens, (lc50 51.29 and 125.89 mg/l within 24 hr, and 21.38 and 38.11 mg/l within 48 hr, respectively). sunlight, ph, and turbidity ... | 2001 | 11775110 |
| evaluation of a pcr-elisa to detect wuchereria bancrofti in culex pipiens from an egyptian village with a low prevalence of filariasis. | the programmes for the elimination of bancroftian filariasis that have been implemented in the nile delta of egypt are expected to lead to substantial reductions in filarial loads in the treated populations. better methods than those currently available are needed for monitoring the efficacy of these and similar efforts at intervention. a pcr-elisa was therefore evaluated as an epidemiological tool for the detection of the wuchereria-bancrofti-specific sspi repeat in pools of culex pipiens colle ... | 2001 | 11784438 |
| binding properties of bacillus thuringiensis cry4a toxin to the apical microvilli of larval midgut of culex pipiens. | cry4a is a dipteran-specific delta-endotoxin produced by bacillus thuringiensis, and toxic to culex pipiens (mosquito) larvae. the immunohistochemical staining of the midgut sections of c. pipiens larvae revealed that cry4a bound in vitro and in vivo to the microvilli of the epithelial cells of posterior midgut and gastric caecae. the binding of digoxigenin-labeled cry4a (dig-cry4a) to the apical microvilli was almost abolished in the presence of excess unlabeled cry4a, suggesting that the bindi ... | 2001 | 11791714 |
| structure and seasonality of nearctic culex pipiens populations. | the abundance and structure of urban autogenous and anautogenous populations of culex pipiens mosquitoes were documented systematically in boston, ma, during three successive years. autogenous larvae become abundant mainly in enclosed sites and anautogenous larvae in sites that provide free access and egress. both populations begin to proliferate when the water temperature exceeds 15 degrees c during june. larval anautogenous mosquitoes increase in abundance 10-fold in two weeks and autogenous i ... | 2001 | 11797779 |
| west nile virus: uganda, 1937, to new york city, 1999. | west nile virus, first isolated in 1937, is among the earliest arthropod-borne viruses discovered by humans. its broad geographical distribution, not uncommon infection of humans, transmission by mosquitoes, and association with wild birds as enzootic hosts were well documented by the mid-1960s. however, west nile virus was not considered to be a significant human pathogen because most infections appeared to result in asymptomatic or only mild febrile disease. several epidemics had been document ... | 2001 | 11797781 |
| potential north american vectors of west nile virus. | the outbreak of disease in the new york area in 1999 due to west nile (wn) virus was the first evidence of the occurrence of this virus in the americas. to determine potential vectors, more than 15 mosquito species (including culex pipiens, cx. nigripalpus, cx. quinquefasciatus, cx. salinarius, aedes albopictus, ae. vexans, ochlerotatus japonicus, oc. sollicitans, oc. taeniorhynchus, and oc. triseriatus) from the eastern united states were evaluated for their ability to serve as vectors for the ... | 2001 | 11797788 |
| west nile virus surveillance using sentinel birds. | captive and free-ranging birds have been used for decades as living sentinels in arbovirus surveillance programs. this review summarizes information relevant to selecting sentinel bird species for use in surveillance of west nile (wn) virus. although experience using avian sentinels for wn virus surveillance is limited, sentinels should be useful for both detecting and monitoring wn virus transmission; however, sentinel bird surveillance systems have yet to be adequately tested for use with the ... | 2001 | 11797805 |
| west nile virus infection in birds and mammals. | west nile virus (wnv) was found throughout new york state in year 2000. the epicenter was located in new york city with a high level of activity in the immediately surrounding counties, including rockland, westchester, nassau, and suffolk. during 2000, wnv testing was performed by the wadsworth center on 3,687 dead birds, representing 153 species, 46 families, and 18 orders. there were 1,203 wnv-positive birds, representing 63 species, 30 families and 14 orders. the percentage of wnv-positive bi ... | 2001 | 11797807 |
| epidemic west nile encephalitis in romania: waiting for history to repeat itself. | seroprevalence data suggest that west nile virus activity in southern romania dates to the 1960s or earlier. in the summer of 1996, southeastern romania and especially bucharest experienced an unprecedented epidemic of west nile encephalitis/meningitis, with at least 393 hospitalized cases and 17 deaths. contributing factors included a susceptible avian population and urban/suburban infrastructural conditions that favored the production of large numbers of culex pipiens pipiens. the epidemic end ... | 2001 | 11797808 |
| a sensitive and rapid assay for homologous recombination in mosquito cells: impact of vector topology and implications for gene targeting. | recent progress in insect transgenesis has been dramatic but existing transposon-based approaches are constrained by position effects and potential instability. gene targeting would bring a number of benefits, however progress requires a better understanding of the mechanisms involved. much can be learned in vitro since extrachromosomal recombination occurs at high frequency, facilitating the study of multiple events and the impact of structural changes among the recombining molecules. we have i ... | 2001 | 11801182 |
| larvicidal activity of extracts from quercus lusitania var. infectoria galls (oliv.). | the present study indicates the efficacy of extracts and fractions of quercus lusitania var. infectoria galls (oliv.) as larvicidal agents and their possible use in biological control of culex pipiens, the urban nuisance mosquito. extracts and fractions were tested against second and fourth instar larvae. the lc(50) values of gallotannins were 335 and 373 ppm, respectively for the 2nd and 4th instar period. the most interesting value of lc(50) (24 h) is obtained with the fraction f(2) (60 ppm). | 2002 | 11801390 |
| larvicidal properties of decomposed leaf litter in the subalpine mosquito breeding sites. | the larvicidal properties of the dietary leaf litter originating from the vegetation surrounding the subalpine mosquito breeding sites were investigated by using 10-month decomposed alder leaf litter against different field collections of culicine taxa of various ecological origin (aedes cantans, aedes caspius, aedes cataphylla, aedes detritus, aedes punctor, aedes pullatus, aedes rusticus, anopheles claviger, culex hortensis, culex pipiens, culiseta morsitans). larvae originating from sites wit ... | 2002 | 11804062 |
| identification and characterization of novel organophosphate detoxifying esterase alleles in the guangzhou area of china. | in the mosquito culex pipiens, various alleles at the ester locus provide insecticide resistance. these resistance alleles display a heterogeneous geographical distribution, particularly in china, where they are highly diverse. a new resistance allele, ester9, coding for the overproduced esterases a9 and b9, is characterized and compared to the known resistant allele ester8 isolated from the same southern china sample (from guangzhou). both alleles provide low but significant resistance to chlor ... | 2001 | 11804460 |
| characterization of wolbachia host cell range via the in vitro establishment of infections. | maternally transmitted bacteria of the genus wolbachia are obligate, intracellular symbionts that are frequently found in insects and cause a diverse array of reproductive manipulations, including cytoplasmic incompatibility, male killing, parthenogenesis, and feminization. despite the existence of a broad range of scientific interest, many aspects of wolbachia research have been limited to laboratories with insect-rearing facilities. the inability to culture these bacteria outside of the invert ... | 2002 | 11823204 |
| insecticide resistance in the mosquito culex pipiens: what have we learned about adaptation? | resistance to organophosphate (op) insecticide in the mosquito culex pipiens has been studied for ca. 30 years. this example of micro-evolution has been thoroughly investigated as an opportunity to assess precisely both the new adapted phenotypes and the associated genetic changes. a notable feature is that op resistance is achieved with few genes, and these genes have generally large effects. the molecular events generating such resistance genes are complex (e.g., gene amplification, gene regul ... | 2001 | 11838771 |
| naturally exposed populations differ in their t1 and t2 responses to the circumsporozoite protein of plasmodium falciparum. | t-cell responses directed against the circumsporozoite protein (cs) of plasmodium falciparum can mediate protection against malaria. we determined the frequency of t cells reactive to different regions of the cs in the blood of donors naturally exposed to p. falciparum by examining t1 (gamma interferon [ifn-gamma] elispot assay), t2 (interleukin 4 [il-4] elispot assay), and proliferative t-cell responses. the proliferative responses were weak, which confirmed previous observations. the responses ... | 2002 | 11854234 |
| selection in the evolution of gene duplications. | gene duplications have a major role in the evolution of new biological functions. theoretical studies often assume that a duplication per se is selectively neutral and that, following a duplication, one of the gene copies is freed from purifying (stabilizing) selection, which creates the potential for evolution of a new function. | 2002 | 11864370 |
| characterization of cyt2bc toxin from bacillus thuringiensis subsp. medellin. | we cloned and sequenced a new cytolysin gene from bacillus thuringiensis subsp. medellin. three is240-like insertion sequence elements and the previously cloned cyt1ab and p21 genes were found in the vicinity of the cytolysin gene. the cytolysin gene encodes a protein 29.7 kda in size that is 91.5% identical to cyt2ba from bacillus thuringiensis subsp. israelensis and has been designated cyt2bc. inclusions containing cyt2bc were purified from the crystal-negative strain spl407 of b. thuringiensi ... | 2002 | 11872472 |
| synergistic interaction between two cockroach sodium channel mutations and a tobacco budworm sodium channel mutation in reducing channel sensitivity to a pyrethroid insecticide. | pyrethroid insecticide resistance due to reduced nerve sensitivity, known as knockdown resistance (kdr or kdr-type), is linked to multiple point mutations in the para-homologous sodium channel genes. previously we demonstrated that two mutations (e434k and c764r) in the german cockroach sodium channel greatly enhanced the ability of the l993f mutation (a known kdr -type mutation) to reduce sodium channel sensitivity to deltamethrin, a pyrethroid insecticide. neither e434k nor c764r alone, howeve ... | 2002 | 11886774 |
| novel sodium channel gene mutations in blattella germanica reduce the sensitivity of expressed channels to deltamethrin. | pyrethroid insecticides alter the normal gating of voltage-gated sodium channels in the nervous system. three sodium channel mutations (e434k, c764r, l993f) were recently identified in pyrethroid resistant german cockroach populations. in this report, we show that the l993f mutation decreased sodium channel sensitivity to the pyrethroid, deltamethrin, by five-fold in xenopus oocytes. in contrast, neither e434k nor c764r alone decreased channel sensitivity to deltamethrin. however, e434k or c764r ... | 0 | 11886779 |
| larvicidal activity of isobutylamides identified in piper nigrum fruits against three mosquito species. | the insecticidal activity of materials derived from the fruits of piper nigrum against third instar larvae of culex pipiens pallens, aedes aegypti, and a. togoi was examined and compared with that of commercially available piperine, a known insecticidal compound from piper species. the biologically active constituents of p. nigrum fruits were characterized as the isobutylamide alkaloids pellitorine, guineensine, pipercide, and retrofractamide a by spectroscopic analysis. retrofractamide a was is ... | 2002 | 11902925 |
| temperature and genotypic effects on life history and fluctuating asymmetry in a field strain of culex pipiens. | fluctuating asymmetry (fa) has been proposed as a tool to measure levels of stress experienced by populations of organisms during development. to be of value as a bio-marker to highlight conditions at particular sites, it is important that variation in fa is due to environmental (eg pollution) variation and not genetic variation among populations and families, in other words heritability for fa should be very close to zero. a full-sib design was set up in which families of culex pipiens mosquito ... | 2002 | 11920140 |
| effect of holding conditions on the detection of west nile viral rna by reverse transcriptase-polymerase chain reaction from mosquito (diptera: culicidae) pools. | we evaluated the effect of holding temperature and time between mosquito death and processing mosquito pools for virus detection on our ability to detect west nile (wn) viral rna from pools of mosquitoes by reverse transcriptase-polymerase chain reaction (rt-pcr). pools of 24 uninfected culex pipiens l. mosquitoes were "spiked" with either a single cx. pipiens that had been inoculated previously with wn virus or with an uninfected mosquito. these pools were held dry at 20, 4, -20, or -70 degrees ... | 2002 | 11931239 |
| reproductive activity and survival of culex pipiens pallens and culex quinquefasciatus (diptera: culicidae) in japan at high temperature. | the egg hatchability, insemination, and longevity of japanese culex pipiens pallens coquillett and japanese culex quinquefasciatus say were compared at 25 and 30 degrees c. egg hatchability was high in cx. p. pallens at 25 degrees c, but it was very low at 30 degrees c because almost no females were inseminated at this temperature. in cx. quinquefasciatus, the egg hatchability and insemination rates were very high, even at 30 degrees c. the longevity of adult females and males was generally shor ... | 2002 | 11931255 |
| effect of environmental temperature on the ability of culex pipiens (diptera: culicidae) to transmit west nile virus. | environmental temperature can affect the ability of mosquitoes to transmit an arbovirus. however, results of various studies indicate that these effects are not consistent among viruses or mosquito species, and there is no information available on the effect of environmental temperature on the ability of north american mosquito species to transmit west nile (wn) virus. we evaluated the effect of incubation temperature (18, 20, 26, or 30 degrees c) on the ability of culex pipiens l. derived from ... | 2002 | 11931261 |
| chemical composition and biological activity of the volatiles of anthemis melampodina and pluchea dioscoridis. | the volatile fractions obtained by hydrodistillation of the fresh leaves of anthemis melampodina and pluchea dioscoridis were analysed by gc-ms technique. of 38 components identified in the volatile oil of a. melampodina, santolinatriene was the major component (27.33%). the oil was characterized by a high percentage of monoterpene hydrocarbons (49.94%) while sesquiterpene hydrocarbons and oxygenated sesquiterpenes represented only 7.41% and 11.43% of the oil. 36 components were identified in th ... | 2002 | 11933125 |
| late season commercial mosquito trap and host seeking activity evaluation against mosquitoes in a malarious area of the republic of korea. | field trials evaluating selected commercially available mosquito traps variously baited with light, carbon dioxide, and/or octenol were conducted from 18-27 september 2000 in a malarious area near paekyeon-ri (tongil-chon) and camp greaves in paju county, kyonggi province, republic of korea. the host-seeking activity for common mosquito species, including the primary vector of japanese encephalitis, culex tritaeniorhynchus giles, was determined using hourly aspirator collections from a human and ... | 2002 | 11949213 |
| [cloning and sequence analysis of full-length trypsin cdna of culex pipiens pallens]. | the expression difference of trypsin gene between deltamethrin-resistant strain and -susceptible strain of culex pipiens pallens was further investigated, and the results showed that the expression of trypsin gene were respectively 4.3 and 3.9 fold more in the resistant strain than in the susceptible strain, by reverse northern blot and northern blot assays. a full-length trypsin cdna of 909 base pairs (genbank/ncbi ay034060) with an open reading frame of 786 base pairs was cloned from the const ... | 2002 | 11958130 |
| effects of insect hormones on hemagglutination activity in two members of the culex pipiens complex. | effects of methoprene and 20-hydroxyecdysone on the development and hemagglutination activity (ha) were studied in both sexes of two members of the culex pipiens complex-anautogenous c. p. quinquefasciatus and autogenous c. p. molestus. juvenile hormone analogue (methoprene) and 20-hydroxyecdysone caused developmental changes in both mosquito strains. high larval mortality, prolongation of intermolt period in each larval instar and in the pupal stage, and morphological changes in the larval-pupa ... | 2002 | 11971657 |
| insecticide resistance genes induce a mating competition cost in culex pipiens mosquitoes. | resistance to organophosphorus insecticides (op) in culex pipiens mosquitoes represents a convenient model for investigating the fitness cost of resistance genes and its origin, since both the environmental changes in nature and the adaptive genes are clearly identified. two loci are involved in this resistance--the super-locus ester and the locus ace.1--each displaying several resistance alleles. population surveys have shown differences in fitness cost between these resistance genes and even b ... | 2002 | 11974602 |
| loss of the membrane anchor of the target receptor is a mechanism of bioinsecticide resistance. | the mosquitocidal activity of bacillus sphaericus is because of a binary toxin (bin), which binds to culex pipiens maltase 1 (cpm1), an alpha-glucosidase present in the midgut of culex pipiens larvae. in this work, we studied the molecular basis of the resistance to bin developed by a strain (geo) of c. pipiens. immunohistochemical and in situ hybridization experiments showed that cpm1 was undetectable in the midgut of geo larvae, although the gene was correctly transcribed. the sequence of the ... | 2002 | 11983886 |
| insecticidal properties of essential plant oils against the mosquito culex pipiens molestus (diptera: culicidae). | the insecticidal activities of essential oil extracts from leaves and flowers of aromatic plants against fourth-instar larvae of the mosquito culex pipiens molestus forskal were determined. extracts of myrtus communis l were found to be the most toxic, followed by those of origanum syriacum l, mentha microcorphylla koch, pistacia lentiscus l and lavandula stoechas l with lc50 values of 16, 36, 39, 70 and 89 mg litre-1, respectively. over 20 major components were identified in extracts from each ... | 2002 | 11997977 |
| chemicals of predatory mosquitofish (gambusia affinis) influence selection of oviposition site by culex mosquitoes. | ovipositing insects may avoid aquatic sites where there is high predation risk to their offspring, but the proximate mechanisms that mediate avoidance behavior are poorly resolved. we conducted an experiment to determine whether mosquitoes would reduce oviposition rates in pools containing chemicals of the mosquitofish (gambusia affinis), a voracious predator that is widely employed to control mosquitoes. experimental treatments consisted of outdoor pools that contained known concentrations of f ... | 2002 | 12035927 |
| detection of west nile virus antigen in mosquitoes and avian tissues by a monoclonal antibody-based capture enzyme immunoassay. | an antigen capture immunoassay to detect west nile (wn) virus antigen in infected mosquitoes and avian tissues has been developed. with this assay purified wn virus was detected at a concentration of 32 pg/0.1 ml, and antigen in infected suckling mouse brain and laboratory-infected mosquito pools could be detected when the wn virus titer was 10(2.1) to 10(3.7) pfu/0.1 ml. in a blindly coded set of field-collected mosquito pools (n = 100), this assay detected wn virus antigen in 12 of 18 (66.7%) ... | 2002 | 12037058 |
| experimental transmission of eastern equine encephalitis virus by ochlerotatus j. japonicus (diptera: culicidae). | we evaluated the potential for ochlerotatus j. japonicus (theobald), a newly recognized invasive mosquito species in the united states, to transmit eastern equine encephalitis (eee) virus. aedes albopictus (skuse) and culex pipiens (l.) were similarly tested for comparison. ochlerotatus j. japonicus and ae. albopictus became infected and transmitted eee virus by bite after feeding on young chickens 1 d after they had been inoculated with eee virus (viremias ranging from 10(7.0-8.7) plaque-formin ... | 2002 | 12061444 |
| strategies for the management of resistance in mosquitoes to the microbial control agent bacillus sphaericus. | bacillus sphaericus (b.spi) strain 2362 has been recognized as a promising mosquito larvicide, and various preparations of this strain have been tested and used in mosquito control programs worldwide. this control agent has advantages of high efficacy, specificity, persistence, and environmental safety. however, resistance in culex pipiens complex mosquitoes to bsph has occurred in both laboratory and field populations, necessitating development of resistance management strategies. studies were ... | 2002 | 12061449 |
| [genetic analysis of deltamethrin resistance in culex pipiens pallens]. | to analyse the genetic character of deltamethrin resistant laboratory strain (resistant factor being 518) of cx. pipiens pallens. | 1998 | 12078202 |
| high wolbachia density in insecticide-resistant mosquitoes. | wolbachia symbionts are responsible for various alterations in host reproduction. the effects of the host genome on endosymbiont levels have often been suggested, but rarely described. here, we show that wolbachia density is strongly modified by the presence of insecticide-resistant genes in the common house mosquito, culex pipiens. the wolbachia density was estimated using a real-time quantitative pcr assay. strains harbouring different genes conferring resistance were more infected than a susc ... | 2002 | 12079666 |
| tightly bound binary toxin in the cell wall of bacillus sphaericus. | we have shown that urea-extracted cell wall of entomopathogenic bacillus sphaericus 2297 and some other strains is a potent larvicide against culex pipiens mosquitoes, with 50% lethal concentrations comparable to that of the well-known b. sphaericus binary toxin, with which it acts synergistically. the wall toxicity develops in b. sphaericus 2297 cultures during the late logarithmic stage, earlier than the appearance of the binary toxin crystal. it disappears with sporulation when the binary tox ... | 2002 | 12089007 |
| evidence for p-glycoprotein modification of insecticide toxicity in mosquitoes of the culex pipiens complex. | pesticide resistance has parallels with multi-drug resistance syndrome of tumours in clinical medicine, which has been linked to an atp-dependent pump, p-glycoprotein (p-gp). p-gps pump drugs out of the cell, thereby reducing cellular concentrations of the chemical. p-gps have been found in several invertebrate species and have been shown to provide a defence against environmental xenobiotics, including pesticides. this study used a model cell culture system to investigate the interaction of pes ... | 2002 | 12109718 |
| locomotion through use of the mouth brushes in the larva of culex pipiens (diptera: culicidae). | the larva of the mosquito culex pipiens is a filter-feeder and is able to use the feeding current generated by its mouth brushes to glide slowly through the water. the hydrodynamics of the mouth brushes, and of gliding, were investigated by visualizing the feeding current using dyes. unlike the mouth brushes of a sessile filter-feeder such as the blackfly larva, those of c. pipiens function more like 'paddles' than 'rakes', a beneficial adaptation to life in still as opposed to running water. te ... | 2001 | 12123291 |
| the use of commercial saponin from quillaja saponaria bark as a natural larvicidal agent against aedes aegypti and culex pipiens. | the larvicidal activity of commercial bark saponin extract (sigma) from quillaja saponaria was studied on 3rd-4th instar larvae of aedes aegypti and culex pipiens (vectors for dengue fever and western nile virus, respectively). the larvae were exposed to serial concentrations (1000, 800, 500, 300, 100, 10, 1, 0.1 and 0.01 mg/l) of the extract for 1, 3, 5, 7 and 11 days. the results indicate that commercial bark saponin is toxic, causing 100% larval mortality in a. aegypti and c. pipiens after 1 ... | 2002 | 12127245 |
| experimental vertical transmission of west nile virus by culex pipiens (diptera: culicidae). | despite the detection of west nile (wn) virus in overwintering culex pipiens l. in new york in february 2000, the mechanism by which this virus persists throughout the winter to initiate infections in vertebrate hosts and vectors the following spring remains unknown. after a blood meal, parous mosquitoes generally do not survive until spring and gonotrophic dissociation occurs in only a small percentage of the population. to investigate vertical transmission as a means of viral survival during i ... | 2002 | 12144296 |
| identification of mosquito avian-derived blood meals by polymerase chain reaction-heteroduplex analysis. | a polymerase chain reaction (pcr) heteroduplex assay (hda) was developed to identify avian derived mosquito blood meals to the species level. the assay used primers amplifying a fragment of the cytochrome b gene from vertebrate but not invertebrate species. in culex tarsalis fed on quail, pcr products derived from the quail cytochrome b gene were detected seven days post-engorgement. in an analysis of wild-caught mosquitoes, 85% of blood-fed mosquitoes produced detectable pcr products. heterodup ... | 0 | 12201598 |
| what can we hope to gain for trypanosomiasis control from molecular studies on tsetse biology ? | at times of crisis when epidemics rage and begin to take their toll on affected populations, as we have been witnessing with african trypanosomiasis in subsahara, the dichotomy of basic versus applied research deepens. while undoubtedly the treatment of thousands of infected people is the top priority, without continued research and development on the biology of disease agents and on ecological and evolutionary forces impacting these epidemics, little progress can be gained in the long run for t ... | 2002 | 12234385 |
| behavioural determinants of gene flow in malaria vector populations: anopheles gambiae males select large females as mates. | plasmodium-refractory mosquitoes are being rapidly developed for malaria control but will only succeed if they can successfully compete for mates when released into the wild. pre-copulatory behavioural traits maintain genetic population structure in wild mosquito populations and mating barriers have foiled previous attempts to control malaria vectors through sterile male release. | 2002 | 12296972 |
| larvicidal activity of leguminous seeds and grains against aedes aegypti and culex pipiens pallens. | larvicidal activity of methanol extracts of 26 leguminous seeds and 20 grains against early 4th-stage larvae of aedes aegypti and culex pipiens pallens was examined. at 200 ppm of the extracts from cassia obtusifolia, cassia tora, and vicia tetrasperma, more than 90% mortality was obtained in larvae of ae. aegypti and cx. pipiens pallens. extract of c. tora gave 86.7 and 100% mortality in the larvae of ae. aegypti and cx. pipiens pallens at 40 ppm but 59.2 and 78.3% mortality against larvae of a ... | 2002 | 12322944 |
| high resistance to bacillus sphaericus binary toxin in culex pipiens (diptera: culicidae): the complex situation of west mediterranean countries. | this study was aimed at clarifying the nature of the resistance to bacillus sphaericus neide (bs) that culex pipiens l. has developed in west mediterranean countries, france, and tunisia. two recessive and sex-linked mutants, sp-1r and sp-2r, were previously detected in southern france. here, the tunisian resistance was also shown to involve a single recessive and sex-linked gene that was temporarily named sp-t(r). in addition, sp-1r, sp-2r, and sp-t(r) were shown to separately confer a similar ... | 2002 | 12349855 |
| host-feeding habits of culex and other mosquitoes (diptera: culicidae) in the borough of queens in new york city, with characters and techniques for identification of culex mosquitoes. | the host-feeding patterns of mosquitoes (n = 247) collected in the borough of queens in new york city in july and august 2000 were investigated using an indirect elisa and a polymerase chain reaction (pcr)-heteroduplex assay. culex pipiens l. and cx. restuans theobald fed primarily on birds, and their feeding habits support their implication as enzootic vectors of west nile virus. culex salinarius coquillett and coquillettidia perturbans (walker) fed mainly on mammals, with fewer blood meals tak ... | 2002 | 12349862 |
| trypanosoma avium of raptors (falconiformes): phylogeny and identification of vectors. | avian trypanosomes are widespread parasites of birds, the transmission of which remains mostly unclear, with various blood-sucking insects mentioned as possible vectors. a search for vectors of trypanosomes of sparrowhawk (accipiter nisus), buzzard (buteo buteo), lesser-spotted eagle (aquila pomarina) and kestrel (falco tinnunculus) was performed in czech and slovak republics. black flies (eusimulium spp.), hippoboscid flies (ornithomyia avicularia), mosquitoes (culex pipiens pipiens) and biting ... | 2002 | 12358422 |
| laboratory evaluation of mesocyclops annulatus (wierzejski, 1892) (copepoda: cyclopidea) as a predator of container-breeding mosquitoes in argentina. | in laboratory bioassays we tested the predatory capacity of the copepod mesocyclops annulatus on aedes aegypti and culex pipiens larvae. a single adult female of m. annulatus caused 51.6% and 52.3% mortality of 50 first instar larvae of ae. aegypti and cx. pipiens respectively, in a 72 h test period. when alternative food was added to the containers, mortality rates declined to 16% and 10.3% for ae. aegypti and cx. pipiens respectively. when 50 first instar larvae of each of the two mosquito spe ... | 2002 | 12386705 |
| potential of origanum compactum as a cercaricide in morocco. | at 1 mg/litre, an ethyl-acetate extract of the molluscicidal plant origanum compactum benth. (lamiaceae) immobilized all of the furcocercariae of schistosoma haematobium exposed to it, within 15 min. this apparently cercaricidal activity was attributed to the presence of terpenoids and flavonoids in the extract. encouragingly, several non-target aquatic organisms (larvae of culex pipiens and artemia salina and adult gambusia affinis) and drosophila melanogaster appeared largely unaffected by exp ... | 2002 | 12396321 |
| a novel acetylcholinesterase gene in mosquitoes codes for the insecticide target and is non-homologous to the ace gene in drosophila. | acetylcholinesterase (ache) is the target of two major insecticide families, organophosphates (ops) and carbamates. ache insensitivity is a frequent resistance mechanism in insects and responsible mutations in the ace gene were identified in two diptera, drosophila melanogaster and musca domestica. however, for other insects, the ace gene cloned by homology with drosophila does not code for the insensitive ache in resistant individuals, indicating the existence of a second ace locus. we identifi ... | 2002 | 12396499 |
| effects of diflubenzuron on growth and glutathione in mosquito fish (gambusia affinis). | although some biological control agents and related biorational approaches are available for mosquito control, insecticides remain the principal control method. in addition, the secondary affects of conventional insecticides in environment has led to the discovery of more target-specific chemical such as insect growth regulators. dimilin (25% wp), the common name of diflubenzuron, prevent molting by interfering with chitin synthesis in several insect orders. this study evaluate toxicity of this ... | 2001 | 12425112 |
| intradermal skin tests in equine dermatology: a study of 83 horses. | allergic diseases are often diagnosed clinically in the horse without performing diagnostic tests. the purpose of this work was to contribute to the validation of intradermal skin tests in the horse. eighty-three horses, 14 showing skin or respiratory signs of supposed allergic origin, were subjected to an intradermal skin test using 6 different allergens, positive and negative controls. the tests were read for all animals after 20 min, and for 29 horses after 1 and 4 h. additionally, 19 horses ... | 2002 | 12455836 |
| detection of west nile virus-infected mosquitoes and seropositive juvenile birds in the vicinity of virus-positive dead birds. | mosquitoes and wild birds were collected from three sites near locations in the new york city metropolitan area where single, west nile (wn) virus-positive dead birds were found early in the 2000 transmission season. the mosquitoes were tested for the presence of infectious virus with a vero cell culture assay and for wn viral rna by using reverse transcriptase-polymerase chain reaction (rt-pcr) protocols. serum samples from wild birds were tested for the presence of neutralizing antibodies agai ... | 2002 | 12479550 |
| positive findings of borrelia burgdorferi in culex (culex) pipiens pipiens larvae in the surrounding of brno city determined by the pcr method. | after first finding borrelia in the midgut of imago mosquitoes, we concentrated on the presence of borrelia in mosquito development stages--larvae of the third or fourth instar. in the summer season in the years of 2000-2001 a total of 439 culex (culex) pipiens pipiens larvae were collected from a barrel of rainwater in the obrany holiday area of brno city (east moravia, czech republic). the larvae midgut was observed under dark-field microscopy. ten dfm positive samples (2.28%) were further ana ... | 2002 | 12498597 |
| role of the domestic chicken (gallus gallus) in the epidemiology of urban visceral leishmaniasis in brazil. | zoonotic visceral leishmaniasis (zvl) is a serious public health problem in several brazilian cities. although the proximity of chicken houses is often cited as a risk factor in studies of urban zvl, the role chickens play in the epidemiology of the disease has not been defined. chickens attract both male and female sand flies (lutzomyia longipalpis) but are unable to sustain leishmania infections, and their presence may exert a zooprophylactic effect. we discuss environmental, physiologic, soci ... | 2002 | 12498667 |
| isolation and genetic characterization of rift valley fever virus from aedes vexans arabiensis, kingdom of saudi arabia. | an outbreak of rift valley fever in the kingdom of saudi arabia and yemen in 2000 was the first recognized occurrence of the illness outside of africa and madagascar. an assessment of potential mosquito vectors in the region yielded an isolate from aedes vexans arabiensis, most closely related to strains from madagascar (1991) and kenya (1997). | 2002 | 12498669 |
| hepatitis c virus and culex pipiens complex. | 2002 | 12512831 | |
| malariasphere: a greenhouse-enclosed simulation of a natural anopheles gambiae (diptera: culicidae) ecosystem in western kenya. | the development and implementation of innovative vector control strategies for malaria control in africa requires in-depth ecological studies in contained semi-field environments. this particularly applies to the development and release of genetically-engineered vectors that are refractory to plasmodium infection. here we describe a modified greenhouse, designed to simulate a natural anopheles gambiae giles ecosystem, and the first successful trials to complete the life-cycle of this mosquito ve ... | 2002 | 12537599 |
| the genomics of insecticide resistance. | genomic technologies are revealing several mechanisms of insecticide resistance involving enhanced detoxification or reduced target-site sensitivity that had previously defied molecular analyses. genome projects are also revealing some potentially far-reaching consequences for pest-insect genomes of the rapid accumulation of multiple resistance mutations in very short periods of evolutionary time. | 2003 | 12540295 |
| comparison of vero cell plaque assay, taqman reverse transcriptase polymerase chain reaction rna assay, and vectest antigen assay for detection of west nile virus in field-collected mosquitoes. | mosquitoes collected during the epidemic of west nile virus (wn) in staten island, ny, during 2000 were identified to species, grouped into pools of up to 50 individuals, and tested for the presence of wn by using taqman reverse transcriptase polymerase chain reaction (rt-pcr) to detect west nile viral rna, vero cell plaque assay to detect infectious virus, and vectest wnv/sle antigen panel assay. a total of 10,866 specimens was tested in 801 pools. analysis of results indicated that taqman rt-p ... | 2002 | 12542186 |
| larvicidal effect of the juvenile hormone mimic pyriproxyfen on culex pipiens. | the larvicidal activity of the juvenile hormone mimic pyriproxyfen was evaluated against the 4th larval instar of culex pipiens under 5 constant temperatures in the laboratory. toxicity of this insect compound increased with temperature. the 50% lethal concentrations ranged between 0.00111 ppm at 20 degrees c and 0.00013 ppm at 32 degrees c. a similar trend was observed for the 90% lethal concentrations, which varied from 0.00379 ppm to 0.00024 ppm at the 2 temperatures, respectively. some effec ... | 2002 | 12542190 |
| repellent activities of essential oils and monoterpenes against culex pipiens pallens. | essential oils of eulcalyptus globulus, lavender officinalis, rosemarinus officinalis, and thymus vulgaris were examined for their repellent activities against culex pipiens pallens. all 4 essential oils effectively repelled adult mosquitoes on hairless mice. essential oil of t. vulgaris (thyme) had potent repellent activity within the tested materials, with a protection rate of 91% at a concentration of 0.05% topical treatment. thyme essential oil significantly extended the duration of protecti ... | 2002 | 12542193 |
| [cloning and expression of a resistant culex gene in escherichia coli]. | recombinant plasmid prlb1 was constructed from detoxifying gene b1 of pesticide resistant culex pipiens quinquefasciatus and from plasmid prl439 contained the strong promoter ppsba. the positive clone was identified by digestion and southern analysis. expression of recombinant plasmid containing esterase gene was detected. an engineered bacterium possessing high enzyme activity was obtained and immobilized. it can effectively degrade the specific substrate alpha-naphthyl acetate (alpha-na) and b ... | 2000 | 12548933 |
| [cloning and expression of the binary toxin genes of bacillus sphaericus c3-41 in a crystal minus b. thuringiensis subsp. israelensis]. | bacillus sphearicus c3-41, belonging to serotype h5a5b, is ahighly toxic strain isolated from a mosquito-breeding site in china. it has been shown that it had a higher toxicity against culex spp. than the reference strain 2362 at the laboratory and field conditions. using synthetic oligonucleotides designed on the basis of the binary toxin gene sequence of 2362, a 1.1 kb dna fragment was produced and the genetic library was prepared from a hindiii digest of total dna from c3-41. one colony conta ... | 1999 | 12555398 |
| laboratory evaluation of a helicosporidium sp. (protozoa: helicosporida) as an agent for the microbial control of mosquitoes. | a helicosporidium sp. isolated from diseased larvae of culex pipiens l. in egypt was assessed for its microbial control potential against mosquito larvae. dose infectivity and dose mortality of the pathogen was determined for each larval instar of cx. pipiens. helicosporidium sp was infectious to aedes caspius (pallas), c. antennatus (becker), c. perexiguus theobald, and culiseta longiareolata (macquart). using 24-hr exposures of first instar larvae to a range of concentrations between 50 and 5 ... | 2001 | 12557926 |
| studies on the present status of insecticides resistance on mosquitoes using the diagnostic dosages in el-fayium governorate, a spot area of malaria in egypt. | insecticides susceptibility tests were conducted using the world health organization diagnostic doses on the adult and larvae of anopheles pharoensis and culex pipiens mosquitoes from fayium governorate in egypt. insecticides used were malathion, fenitrothion, temephos, diazinon, bromophos and fenthion from organophosphorous group and deltamethrin, permethrin and cypermethrin from synthetic pyrethroid group while propoxur was from carbamate group. larvae of a. pharoensis were resistant to fenitr ... | 2001 | 12557941 |
| the insecticidal activity of cyanobacteria against four insects, two of medical importance and two agricultural pests with reference to the action on albino mice. | acute lethal toxicity of cyanobacteria (blue-green algae) was investigated against 3rd larval stages of musca domestica, and culex pipiens, and 4th larval stages of spodoptera littoralis and agrotis ipsilon. the ld50s were 1.94, 2.33, 7.59 and 9.10 microg for m. domestica, c. pipiens, s. littoralis and a. ipsilon respectively. the slope functions were 4,045 +/- 0.332 (m. domestica), 4.122 +/- 0.336 (c. pipiens), 4.15 +/- 0.35 (s. littoralis) and 3.72 +/- 0.34 (a. ipsilon). these ld50s markedly a ... | 1999 | 12561932 |
| pathological alterations in the ovaries of culex pipiens induced by fixed oil extracts from thevetia peruvine, datura stramonium and acacia sp. | the fixed oil extracts from thevetia peruvine, datura stramonium and acacia sp. were tested on culex pipiens larvae. the estimated sublethal concentrations (lc50) were used in the present studies. the reproductive potential of females and the histochemistry of their ovaries were determined. the results indicated that oil treatments of larvae caused drastic changes in reproduction potential of female mosquitoes including the ovarian development in the first gonotrophic cycle, fecundity and fertil ... | 1999 | 12561936 |
| [cloning and identification of cytochrome p450 resistance related genes in the mosquito, culex pipiens pallens]. | to inquire into the relationship between cytochrome p450 and deltamethrin resistance. | 2000 | 12567630 |
| [cloning and identification of deltamethrin-resistance or susceptibility associated genes of culex pipiens pallens]. | to obtain deltamethrin-resistance or susceptibility associated genes of culex pipiens pallens. | 2001 | 12571962 |
| [microplate test of non-specific esterase detection for insecticide resistance of culex pipiens pallens]. | 2001 | 12572008 | |
| [relative activity of succinate dehydrogenase in mitochondria of thoracic muscles of culex tritaeniorhyncus and culex pipiens pallens]. | 2001 | 12572057 | |
| [observation on hemocytes of culex pipiens quinquefasciatus larvae infected by lagenidium giganteum]. | to explore the possible defensive immunity of culex pipiens quinquefasciatus larvae after being infected by lagenidium giganteum. | 2001 | 12572061 |
| [inhibition of in vitro translation of esterase mrna of dipterex-resistant mosquito (culex pipiens pallens) by antisense nucleic acids]. | to examine the inhibitory effect of antisense nucleic acid on the in vitro translation of esterase mrna from dipterex-resistant culex pipiens pallens. | 2001 | 12572062 |
| [synthesis and insecticidal activity of some benzimidazolic and benzothiazolic derivatives]. | the benzimidazolic and benzothiazolic derivatives with a (ch(2))n radical in 2 position of the heterocycle had been synthesized and then tested for their insecticidal activity on culex pipiens larvae. the benzothiazolic derivatives were found to be the most active. the study has also showed that this activity was related to the nature of the substitute in 2 position of the heterocycle. this activity increased when (ch(2))n chain increased until n=6; above this value, the activity decreased. | 2003 | 12589255 |
| differences in extent of genetic introgression between sympatric culex pipiens and culex quinquefasciatus (diptera: culicidae) in california and south africa. | comparisons of five morphological characters, 12 enzyme electrophoresis profiles, and wolbachia pipientis infection rates were used to characterize populations of members of the culex pipiens l. complex in california and south africa. in south africa, male phallosome dv/d ratio, male maxillary palp index, branching of siphonal seta 1a, the enzyme locus mdhp-1, and w. pipientis infection rates proved highly diagnostic for separating culex quinquefasciatus from cx. pipiens phenotypes. in johannesb ... | 2003 | 12597651 |
| binding properties of bacillus thuringiensis cry1c delta-endotoxin to the midgut epithelial membranes of culex pipiens. | the cry1c delta-endotoxin from bacillus thuringiensis is toxic to both lepidopteran and dipteran insect larvae. to analyze the dipteran-specific insecticidal mechanisms, we investigated the properties of cry1c binding to the epithelial cell membrane of the larval midgut from the mosquito culex pipiens in comparison with dipteran-specific cry4a. immunohistochemical staining of the larval midgut sections from culex pipiens showed that cry1c and cry4a bound to the microvilli of the epithelial cells ... | 2003 | 12619679 |
| experimental infection of north american birds with the new york 1999 strain of west nile virus. | to evaluate transmission dynamics, we exposed 25 bird species to west nile virus (wnv) by infectious mosquito bite. we monitored viremia titers, clinical outcome, wnv shedding (cloacal and oral), seroconversion, virus persistence in organs, and susceptibility to oral and contact transmission. passeriform and charadriiform birds were more reservoir competent (a derivation of viremia data) than other species tested. the five most competent species were passerines: blue jay (cyanocitta cristata), c ... | 2003 | 12643825 |
| emergence of resistance and resistance management in field populations of tropical culex quinquefasciatus to the microbial control agent bacillus sphaericus. | in recent years, highly potent mosquitocidal strains of the microbial agent bacillus sphaericus (bsph) have been isolated and developed for the control of mosquito larvae around the world. laboratory selection experiments with the most active strains and their use in large-scale operational mosquito control programs resulted in the emergence of resistance in larvae of the culex pipiens complex. this generated great concern among vector control agencies around the world, who feared reduced effica ... | 2003 | 12674533 |
| migratory birds and west nile virus. | west nile virus was first recorded in the new world during august 1999 in new york city. aetiology of the disease in the old world indicated birds as the likely introductory and amplifying hosts with ornithophilous mosquitoes, e.g. culex pipiens, as the principal vectors. speculation regarding likely agents for movement of the virus in its new environment focused on migratory birds, but evidence to date is equivocal. while spread of the disease has been fairly rapid, at a rate of roughly 70 km a ... | 2003 | 12675936 |
| relationships between wuchereria bancrofti microfilaria counts in human blood and parasite uptake and maturation in culex pipiens, with observations on the effects of diethylcarbamazine treatment on these parameters. | this study examined relationships between blood microfilaria (mf) counts and parasite uptake and maturation in culex pipiens fed on egyptian volunteers with bancroftian filariasis. uptake of mf and production of infective larvae (l3) were more closely correlated with mf counts in finger prick blood than in venous blood. only a minority of ingested mf developed into l3. few mf were ingested, and very few l3 were produced by mosquitoes that fed on infected subjects who were amicrofilaremic by 50 m ... | 2003 | 12685631 |
| insecticidal activity of a nonsteroidal moulting hormone agonist on mosquito larvae and effects on ecdysteroid amounts. | the secondary effects of conventional insecticides on the environment, vertebrates and beneficial organisms have caused a move to the use of more target-specific chemicals such as insect growth regulators. halofenozide (rh-0345) is a novel nonsteroidal ecdysteroid agonist that induces a precocious and incomplete moult in several insect orders. in the present study, the insecticidal activity of a commercial formulation of halofenozide (23% ec) was evaluated at different concentrations ranging bet ... | 2002 | 12696434 |
| biological and histopathological studies of some plant extracts on larvae of culex pipiens (diptera: culicidae). | the water extract of artemisia monosperma, eichhornia crassipes and zygophyllum coccineum was tested against the 2nd instar larvae of culex pipiens and the resulting pupae and adults. the larvae were exposed to serial concentrations (0.5, 1.0 and 2.0%). all extracts showed marked effects on larval mortality, pupation and adult emergence as compared to the non-treated group. these effects were dose (concentration) dependant (p < 0.001). the results indicate that the water extract of e. crassipes ... | 2003 | 12739811 |
| preliminary field trials with culicinomyces clavosporus against some egyptian mosquitoes in selected habitats. | culicinomyces clavosporus was isolated from diseased larvae of culex pipiens collected from brackish water habitat. pure cultures of the fungus were grown on nutrient agar media. in the laboratory, the egyptian isolate of the fungus was bioassayed against first instar larvae of aedes caspius, cx. antennatus and cx. pipiens. the estimated lc50's for ae. caspius, cx. antennatus and cx. pipiens were 4.4 x 10(2), 7.6 x 10(2) and 11.8 x 10(2) conidia/ml, respectively. field studies were undertaken in ... | 2003 | 12739818 |
| specific sensitization to the common housefly (musca domestica) not related to insect panallergy. | allergy to houseflies is rare. we report a case of respiratory allergy from occupational exposure to houseflies in a farmer. | 2003 | 12752335 |