Publications

host-feeding patterns of culex pipiens and cx. antennatus (diptera: culicidae) from a village in sharqiya governorate, egypt.	host-selection patterns of mosquitoes were determined over a 1-yr period at abu heif, a village in sharqiya governorate, egypt, that has had a history of rift valley fever virus (rvfv) transmission. culex pipiens l. and cx. antennatus becker were the most common mosquito species collected, and 8,252 blood meals from both species were analyzed by a precipitin technique. host availability was estimated by a monthly census of human and animal populations. both mosquito species exhibited opportunist ...	1995	7473609
[characters and insecticidal polypeptide of a new strain of bacillus thuringiensis subsp. kenyae in china].	a new strain of bacillus thurinigiensis bt with high toxicity against noctuidae larvae has been screened for many generations since isolated from larvae candle of aphomia gularis in yiyang county, jiangxi province, in china. by comparison and analysis of results of physiological and biochemical test, flagella antigen identification and esterase type, the strain is identified as h4a-4c bt serovar. kenyae. since its crystal protein type and plasmid type are different from those of bt serovar. keny ...	1995	7483588
rift valley fever virus in the cardia of culex pipiens: an immunocytochemical and ultrastructural study.	in this paper, we consider the movement of rift valley fever (rvf) virus from infected mosquito midgut epithelial cells into the hemocoel as an important factor in the ultimate ability of the insect to transmit the virus. our results are therefore significant in the context of vector competence. the mosquito culex pipiens was identified as the primary vector of rvf in an epidemic that occurred in egypt in the 1970s. on this basis, we have carried out several studies of rvf virus in this mosquito ...	1995	7485683
characterization of clone 13, a naturally attenuated avirulent isolate of rift valley fever virus, which is altered in the small segment.	the 74hb59 strain of rift valley fever (rvf) virus, isolated from a human case in the central african republic, was shown to be composed of a heterogeneous population of viruses when plaque-purified clones were analyzed for their reactivity with monoclonal antibodies (mabs) directed against the nucleocapsid (n) protein or the nonstructural (nss) protein. one of these clones, c13, was of particular interest in that it proved to be avirulent in mice and hamsters, and highly immunogenic. although c ...	1995	7485695
characterization of the unlinked 16s rdna and 23s-5s rrna operon of wolbachia pipientis, a prokaryotic parasite of insect gonads.	the rrna-encoding genes (rdnas) have been cloned and characterized from wolbachia pipientis (wp), the gonadial bacteria-like parasite of the mosquito culex pipiens (cp) and the moth ephestia cautella (ec). in wp from both insect species the rdnas are organized in a way which appears to be very unusual. the rrnas are encoded by two unlinked transcription units, each present in a single copy per genome. one contains the 16s rdna only, while the other is an operon encoding both the 23s and 5s rdnas ...	1995	7489921
resistance to temephos, an organophosphorous insecticide, in culex pipiens from tunisia, north africa.	resistance to temephos, an organophosphorous insecticide (op), was found to be low (2-fold) in 2 culex pipiens populations collected in sayada (mid-eastern tunisia). this resistance was synergized by an esterase inhibitor (def). two sets of over-produced esterases (a2-b2 and a4-b4), known to be involved in resistance, were identified in almost 50% of the examined insects. in addition, 3% of insects had an insensitive acetylcholinesterase. after selecting larvae of one of the samples (es) with te ...	1993	7504077
resistance monitoring in culex pipiens (diptera: culicidae) from central-eastern france.	insensitive acetylcholinesterase (acer) and five over-produced esterases (a1, a2 and b2, and a4 and b4) involved in detoxification are responsible for resistance to organophosphorous insecticides (ops) in culex pipiens l. from the rhône-alpes region, where c. pipiens control is mainly accomplished with the ops temephos and chlorpyrifos using 0.15 mg/liter doses. the strong linkage disequilibria observed between esterases a1 and est-20(0.64), esterases a4 and b4, and esterases a2 and b2 indicate ...	1994	7514668
[resistance to the organophosphate insecticides temephos and malathion in culex pipiens l. (diptera, culicidae) from the adriatic coast near friuli].	susceptibility to organophosphorus insecticides temephos and malathion was tested in culex pipiens l. larvae from friuli adriatic coast (north-east of italy). the samples were collected in various sites of three zones with different intensity of insecticidal treatments. tests were made following the w.h.o. recommendations. the tests were made on larval samples which were exposed for 24 hours to ascending concentrations of each insecticide. from the observed percentage mortalities the lc50 and lc ...	1993	7520564
the same esterase b1 haplotype is amplified in insecticide-resistant mosquitoes of the culex pipiens complex from the americas and china.	in culex pipiens, overproduction of nonspecific esterases is a common mechanism of resistance to organophosphate insecticides. the esterases are attributed to closely linked loci named a and b, and overproduction of all esterases b is due to gene amplification. in order to determine if the esterase b1 identified by electrophoretic studies in culex pipiens mosquitoes from different countries is overproduced due to the amplification of the same dna haplotype, the amplified region encompassing the ...	1995	7538988
resistance to organophosphorous insecticides in culex pipiens quinquefasciatus (diptera: culicidae) from martinique.	before beginning a widespread control program against culex pipiens quinquefasciatus in martinique, resistance to temephos, chlorpyrifos, and two organophosphorous insecticides, was investigated at seven breeding sites. at lc95, populations exhibited resistance ratios between 6.9 and 11.6 for temephos and between 6.4 and 51.4 for chlorpyrifos. overproduced esterases a2-b2 and b1, known to be involved in organophosphorous-resistance, were present at all breeding sites; esterases a2-b2 frequency w ...	1995	7541837
mosquito sensitivity to a scorpion neurotoxin expressed using an infectious sindbis virus vector.	the scorpion, androctonus australis hector, produces an insect-specific toxin (aahit) encoded by the scotox gene. to assess the toxicity of aahit for mosquitoes, we have taken a novel approach to express the scotox gene in vivo. we have engineered a double subgenomic sindbis (dssin) virus that contains the scotox gene in the viral genome and intrathoracically inoculated the virus (te/3'2j/scotox) into mosquitoes (aedes aegypti, ae. triseriatus and culex pipiens), houseflies (musca domestica) and ...	1995	7551198
bacillus thuringiensis serovar higo (flagellar serotype 44), a new serogroup with a larvicidal activity preferential for the anopheline mosquito.	eight strains of bacillus thuringiensis, isolated in japan, formed spherical parasporal inclusions and exhibited low to moderate larvicidal activities for two mosquito species, anopheles stephensi and culex pipiens molestus, but not for another dipteran, telmatoscopus albipunctatus, or two lepidopterans, bombyx mori and hyphantria cunea. the anopheline toxicity (lc50 = 6.3 micrograms ml-1) was > 10 times greater than the activity on the culex mosquito. these strains were assigned to a previously ...	1995	7576527
response of iowa mosquito populations to unusual precipitation patterns as measured by new jersey light trap collections.	new jersey light trap data from 1993, a year with unusually high amounts of precipitation, and 1994 were compared with mean light trap counts for the previous 8-10 years in each of 6 locations. the study took place in iowa. in 1993, aedes trivittatus and culex tarsalis populations were unchanged. anopheles punctipennis and culex pipiens complex populations were significantly higher, and aedes vexans populations increased in all 6 sites, significantly so in 2 sites. species composition was unchan ...	1995	7595446
absence of mating barriers between autogenous and anautogenous culex pipiens l. in egypt.	the existence of pre-mating and post-mating barriers between culex pipiens l. populations and the possibility of interbreeding between autogenous and anautogenous mosquitoes were examined. test mosquito populations were stenogamous with > 83% insemination rates in 20 x 20 x 20 cm cages, regardless of autogeny rates ranging from 10 to 91%. bi-directional crosses between three geographical populations resulted in > 80% hatch rates, indicating full cytoplasmic compatibility. both autogenous and ana ...	1995	7602173
development of a species-diagnostic polymerase chain reaction assay for the identification of culex vectors of st. louis encephalitis virus based on interspecies sequence variation in ribosomal dna spacers.	culex pipiens complex mosquitoes (cx. p. pipiens and cx. p. quinquefasciatus) are among the principal vectors of st. louis encephalitis (sle) virus in the eastern united states; cx. restuans and cx. salinarius play secondary roles in the transmission and maintenance of the virus cycle. accurate identification of these three species in field collections is required for epidemiologic studies of sle virus transmission. we have developed a polymerase chain reaction (pcr) assay for this purpose. spec ...	1995	7625528
the ultrastructure of the foregut and its influence on bancroftian microfilariae ingestion in three egyptian mosquito species.	laboratory observations on the uptake of bancroftian microfilariae (mf.) by three egyptian mosquito species revealed that microfilariae ingested by some tested species were badly damaged during ingestion. the foregut structures in culex pipiens, aedes caspius and anopheles multicolor were investigated by light and scanning microscope techniques. in ae. caspius which have well developed pharyngeal armatures, and an multicolor which have well developed cibarial armatures, high proportion of microf ...	1995	7665933
nutritional reserves in autogenous and anautogenous populations of culex pipiens and aedes caspius (diptera: culicidae).	proteins, carbohydrates, and lipids were compared in larval, pupal, and adult stages of autogenous and anautogenous populations of culex pipiens and aedes caspius. all developmental stages of autogenous mosquitoes accumulated significantly more proteins and carbohydrates than did anautogenous sibligns. for lipids, the same pattern was observed with the exception that adult females of both autogenous and anautogenous ae. caspius had comparable quantities (170-176 micrograms/mg). in general, mosqu ...	1995	7665946
epidemiological surveillance of filariasis after its control in shandong province, china.	shandong province used to be the highly endemic area of wuchereria bancrofti. culex pipiens pallens was the main mosquito vector. after about 30 years of large scale anti-filariasis control campaign, filariasis was controlled throughout the province in 1983. since then, extensive cross-sectional and consecutive longtitudinal surveillances have been carried out. parasitological and entomological data indicated that the microfilaremia rate of the human population, and the natural infection rate of ...	1994	7667720
organophosphorous insecticide susceptibility of mosquitoes in maryland, 1985-89.	from 1985 to 1989, the susceptibility of the 9 major culicine mosquito species in maryland to the larvicide temephos or the adulticide malathion was studied. the susceptibility of culex spp. to temephos has declined in most areas of maryland since 1967; however, only one strain of culex pipiens was found to be temephos resistant in this study. aedes sollicitans, ae. albopictus and ae. taeniorhynchus were temephos susceptible. all mosquitoes tested in the adult stage were susceptible to malathion ...	1993	7682258
mechanisms of insecticide resistance in field populations of culex pipiens from italy.	results of a study on organophosphate (op) resistance carried out on 4 italian field populations of culex pipiens are reported. the a1, a4-b4 and/or a5-b5 nonspecific esterases and insensitive acetylcholinesterase (ache) were detected in our samples. a2-b2 esterases previously recorded in italy were not observed. the a4-b4 and/or a5-b5 esterases were first found in italy where they are at present widespread. both nonspecific esterases and insensitive ache are involved in op resistance, although ...	1993	7688795
evolution of resistance genes in absence of insecticide selection in a hypogeous population of culex pipiens from the french alps.	a monthly survey of resistance gene frequencies was conducted in a larval population of culex pipiens breeding in an hypogeous site ("molestus" form) between july 1989 and september 1991, after interrupting mosquito control. several significant variations in resistance gene frequency were observed. some variations are explained by fitness differences between resistant and susceptible insects, others by an immigration of insects from the surrounding epigeous populations ("pipiens" form), which ar ...	1993	7688796
[the discovery of culex pipiens (diptera: culicidae) in southern yakutia].	the results of the investigation of the distribution of the synanthropic mosquito culex pipiens in dwelling buildings in nehryungri in 1992-1993 are reported. it has been recovered that this mosquito species inhabits all stone buildings and therefore it is a very important problem for city people in the region of investigation.	1994	7700687
protocol for the introduction of new bacillus thuringiensis israelensis products into the routine mosquito control program in germany.	the efficacy of new and frequently used formulations of bacillus thuringiensis israelensis (b.t.i.) has been evaluated in the laboratory and in the field conditions under which they will be used in germany. the principles governing the successful introduction of new formulations of microbial control agents into routine programs have been highlighted. the potency of the formulations in use (teknar, bactimos, and vectobac) and their efficacy against the indigenous mosquito species aedes vexans, ae ...	1994	7707059
mosquito bite anaphylaxis: immunotherapy with whole body extracts.	adverse reactions to mosquito bites have been recognized for some time. these usually consist of large local swellings and redness, generalized urticaria, angioedema and less easily definable responses such as nausea, dizziness, headaches, and lethargy.	1995	7719881
[the recycling of waste water and mosquitoes].	recycling waste water in the achères complex (north-west paris) is based on both sophisticated industrial techniques and simple agricultural methods. the sewage farms and settling pools provide suitable breeding sites for more than ten mosquito species. aedes caspius is the major pest for the local population. moreover culex pipiens (anthropophilic form) breeds in the sewers of the neighbouring towns. mosquito control is based early ground treatment of breeding sites. temephos and fenotrothion a ...	1995	7780672
mosquito transposable elements.	most of the transposons so far characterized from mosquito genomes are retroelements which seem to be distributed worldwide. the juan transposons constitute a family of non-ltr retroelements, or line-retroposons, which are dispersed in the genomes of several mosquito species. three different juan subfamilies have been characterized, each being amplified in the genomes of many strains, if not all, of a given mosquito species. these subfamilies have been designated respectively juan-c in culex pip ...	1994	7813911
[the siphonal index of culex pipiens mosquito larvae (diptera: culicidae) from russia and adjacent countries: its variability and use for the diagnosis of forms].	in 70 natural populations and laboratory strains of culex pipiens from the former soviet union (32 settlements, 37-62 n, 38-93 degrees e) the larval siphonal index was studied, in 29 populations the adult biological peculiarities (the autogeny, the stenogramy and the bloodsucking activity on the human) were studied also in the laboratory. the individual siphonal index varies considerably from 2.2 to 7.9 and has the normal distribution shape. the mean index is correlated with the larval biotope ( ...	1994	7816513
prevention of changes in the electrophoretic mobility of overproduced esterases from organophosphate-resistant mosquitoes of the culex pipiens complex.		1994	7841496
the development of hepatozoon sipedon sp. nov. (apicomplexa: adeleina: hepatozoidae) in its natural host, the northern water snake (nerodia sipedon sipedon), in the culicine vectors culex pipiens and c. territans, and in an intermediate host, the northern leopard frog (rana pipiens).	the life cycle of hepatozoon sipedon sp. nov. was studied in two snake species, the northern water snake and the eastern garter snake, in its mosquito hosts culex pipiens and c. territans, and in the northern leopard frog. gametogenesis, fertilization and sporogony occurred within fat body cells in the haemocoel of mosquitoes that had fed on infected water snakes. mature oocysts averaging 263 microns in diameter and containing more than 500 sporocysts were observed in mosquitoes 28 days post-fee ...	1994	7855120
the suitability of restriction fragment length polymorphism markers for evaluating genetic diversity among and synteny between mosquito species.	restriction fragment length polymorphism (rflp) markers derived from the yellow fever mosquito, aedes aegypti, were used in hybridizations to genomic dna of the following mosquito species: ae. albopictus, ae. togoi, armigeres subalbatus, culex pipiens, and anopheles gambiae. interspecific hybridization with ae. aegypti probes varied from 50% (an. gambiae) to 100% (ae. albopictus) under high stringency conditions. we demonstrated the usefulness of using rflp profiles to examine genetic diversity ...	1994	7909414
rapid assessment of vectorborne diseases during the midwest flood--united states, 1993.	heavy spring and summer rainfall during 1993 caused the most extensive flash and riverine flooding ever recorded in the upper midwestern united states. in portions of the flood region,* standing water provided large expanses of habitat capable of producing large populations of the mosquitoes culex pipiens and cx. tarsalis. these species can rapidly amplify transmission of the arboviruses that cause st. louis encephalitis (sle) and western equine encephalitis (wee). although information from stat ...	1994	7911970
efficacy of clostridium bifermentans serovar malaysia on target and nontarget organisms.	clostridium bifermentans serovar malaysia (c.b.m.) is highly toxic to mosquito larvae. in this study, the following aquatic nontarget invertebrates were treated with high c.b.m. concentrations (up to 1,600-fold the toxic concentration for anopheles stephensi) to study their susceptibility towards the bacterial toxin: planorbis planorbis (pulmonata); asellus aquaticus (isopoda); daphnia pulex (cladocera); cloeon dipterum (ephemeroptera); plea leachi (heteroptera); and eristalis sp., chaoborus cry ...	1994	7912261
insecticide resistance genes in culex pipiens (diptera: culicidae) from italy: esterase b locus at the dna level.	restriction fragment length polymorphism (rflp) analysis at the esterase b locus was performed in samples from four populations of italian culex pipiens pipiens l. to identify correctly, at the molecular level, the resistance gene. the absence of the amplified b2 haplotype was confirmed, indicating that it has not increased in frequency after its detection in continental italy around 1985. the b4 haplotype was detected in all populations at the same frequencies as a previous starch gel survey. t ...	1994	7914542
insecticide susceptibility in mosquitoes (diptera: culicidae) from french polynesia.	susceptibility to six organophosphate (op), two pyrethroid (py), and one carbamate (c) insecticides was investigated in culex pipiens quinquefasciatus say, aedes aegypti (l.), and aedes polynesiensis marks larvae from the island of tahiti. cx. p. quinquefasciatus and ae. aegypti were compared with susceptible reference strains treated simultaneously. a low, but significant, resistance to bromophos (4.6x), chlorpyrifos (5.7x), fenthion (2.4x), fenitrothion (5.0x), temephos (4.3x) and permethrin ( ...	1994	7966164
exposure variables in bancroftian filariasis in the nile delta.	to demonstrate focality of filariasis within endemic rural areas and to define exposure variables which may influence this phenomenon, the population of an agrarian endemic village, of 12,500 individuals, in the nile delta of egypt was censused. a sequential sample of individuals residing in every fifth house was tested for microfilaremia (239 households with 8.6 +/- 3.5 individuals per household (hhd). three areas of the village were tested simultaneously and a questionnaire was filled out for ...	1994	8077763
patterns of erythrocyte digestion by bloodsucking insects: constraints on vector competence.	two general patterns of erythrocyte digestion were observed in representative species from four insect orders. ingested erythrocytes were hemolyzed rapidly, and blood meals remained liquefied within body lice, pediculus humanus l. and the fleas ctenocephalides felis (bouché) and xenopyslla cheopis (rothschild). peritrophic membrane was absent. in contrast, there was a lag time of 6-18 h before substantial degradation of erythrocytes within the blood meals of bed bugs, cimex lectularius l.; the s ...	1993	8094460
endosymbiotic relationship between a rickettsia-like microorganism and the male germ-cells of culex tigripes.	the male mosquitoes of the species culex tigripes possess endosymbionts localized in the cytoplasm of the germ-cells. the somatic cells of the testis do not exhibit this particularity. the spermatogonia, spermatocytes and spermatids all possess a few symbionts. they are eliminated in the residual body at the end of spermiogenesis when the spermatozoon matures. they are absent from the seminal vesicles. a few spermatocytes and spermatids show a proliferation of the endosymbionts. this seems to be ...	1993	8096432
variation of larval susceptibility to lagenidium giganteum in three mosquito species.	a significantly greater number of lagenidium giganteum zoospores were found encysting on the dorsal thoracic surface of anopheles gambiae larvae than on the larvae of aedes aegypti and culex pipiens. however, germ tube penetration in the cuticle of a. gambiae provoked an intense and diffuse melanization which encapsulated the fungus and protected 56% from death. although a small number of zoospores attach to and penetrate the cuticular surface of a. aegypti and c. pipiens approximately 99% of bo ...	1993	8104999
laboratory and field trials of four repellents with culex pipiens (diptera: culicidae).	during operation "desert shield," 16 volunteers field-tested four insect repellents (deet, the lactone cic-4, and the piperidine compounds ai3-37220 and ai3-35765) against biting mosquitoes at king fahd airport, eastern province, saudi arabia. cic-4 and ai3-37220 (25% wt/vol) provided effective (> 90%) protection against bites for 4 h. deet and ai3-35765 protected for only 2 h. the compounds subsequently were evaluated for repellency against laboratory-reared culex pipiens l. cic-4 was more effe ...	1994	8158621
variability in circadian activity patterns within the culex pipiens complex (diptera: culicidae).	circadian activity was compared among four strains of culex pipiens molestus forskal from iran, egypt, two localities (ebira and yanagawa) in nagasaki, japan, and one strain of cx. p. pallens coquillett from japan. under a 16:8 (l:d) h photoperiod, all the strains showed peaks of activity at lights on and off, with additional activity during both light and dark periods; egyptian females and both sexes of cx. p. pallens were inactive during the photophase. under 0:24 (l:d) h, the length of the fr ...	1994	8158629
the selection and genetic analysis of esterase electromorphs in an organophosphate-resistant strain of culex pipiens from italy.	an italian organophosphate-resistant strain of culex pipiens (lucca) was found to be polymorphic for elevated and nonelevated esterases. selection for high esterase activity produced a strain homozygous for elevated esterases a2 and b2. selection for low activity produced a strain homozygous for nonelevated esterases, a4i and b1i. crossing experiments showed that a2 and b2 are coded by separate but closely linked genes, as are a4i and b1i. results indicate that elevated a2 and nonelevated a4i ar ...	1993	8166620
study of the present status of filariasis in an endemic area in giza governorate, egypt.	in a trial to throw some light on the present status of filariasis in giza governorate, both human and mosquitoes were surveyed in two endemic areas: kafr-ghataty and azizya. in kafr-ghataty the clinical cases detected were very rare (0.77%), while no microfilaraemic cases were obtained. the situation was different in azizya village, where no clinical cases were detected but microfilaraemic cases were relatively higher (8%). the results of the larval survey, carried out only in kafr-ghataty, sho ...	1994	8169434
[studies on the susceptibility of anopheles anthropophagus to experimental infection with wuchereria bancrofti].	this paper reports the susceptibility of anopheles anthropophagus (xu et feng, 1975) to experimental infection with wuchereria bancrofti (cobbold, 1877), comparing with that of an. sinensis wiedemann, 1828, culex pipiens quinque fasciatus say, 1823, and aedes togoi (theobald, 1907). of 188 an. anthropophagus, 202 an. sinensis, 280 cx. pipiens quinque fasciatus and 129 ae. togoi infected by the blood of a bancroftian microfilaremia with mff density of 190 mff/20cmm, the infective rates were 35.64 ...	1993	8174212
[analysis of the protein/polypeptide in culex pipiens pallens (diptera:culicidae) during hibernation by two-dimensional gel electrophoresis].	analysis on the protein/polypeptide in culex pipiens pallens (diptera: culicidae) caught from the resting or overwintering places during the 3rd ten-day of september, the 2nd ten-day of december and the 1st ten-day of march in next year in zhengzhou (34 degrees 43' n, 113 degrees 39' e) during hibernation by two-dimensional gel electrophoresis indicated that there were 153, 118 and 169 protein/polypeptide spots in unoverwintering, overwintering and recovering mosquitoes respectively. the molecul ...	1993	8174216
predation by a cyprinodontid fish, aphanius mento, on culex pipiens: effects of alternative prey and vegetation.	we assessed the effects of an alternative prey species (daphnia magna) and a submergent plant (ceratophyllum demersum) on the efficiency of the fish, aphanius mento, to prey on mosquito (culex pipiens) larvae in the laboratory. aphanius mento is an untested biological control candidate of mosquitoes. when d. magna was introduced with equal numbers of cx. pipiens larvae, there was a 50.7% reduction in predation by a. mento on the mosquito larvae. however, the more d. magna a fish ate, the more cx ...	1993	8245949
entrainability of circadian activity of the mosquito culex pipiens pallens to 24-hr temperature cycles, with special reference to involvement of multiple oscillators.	entrainability of the circadian rhythm of mosquito flight and locomotor activity was investigated by giving a 24-hr temperature cycle (28 degrees c for 16 hr, 23 degrees c for 8 hr) to the free-running rhythm or by shifting the temperature cycle. the phase angle difference between the entrained rhythm and the temperature cycle depended on the free-running period, but not on the circadian phase at which the temperature cycle started. the rhythm transients (advancing or delaying) to entrainment de ...	1993	8280910
role of the cryivd polypeptide in the overall toxicity of bacillus thuringiensis subsp. israelensis.	the gene encoding the cryivd protein of b. thuringiensis subsp. israelensis crystals was disrupted by in vivo recombination. the toxicity of the cryivd protein-free inclusions was similar to that of the wild-type crystals on anopheles stephensi larvae but was half the wild-type toxicity on culex pipiens and aedes aegypti larvae.	1993	8285695
mosquito age as a factor influencing the transmission of wuchereria bancrofti.	two mosquito species; culex pipiens and aedes caspius of different ages were experimentally infected with moderate microfilarial densities of wuchereria bancrofti and examined for their vector potential to transmit this parasite. tested age groups of cx. pipiens supported the development of the infective stage of the parasite (l3) but those of ae. caspius arrested its development especially aged mosquitoes. for cx. pipiens, infection rates and the mean number of microfilaria (mf) were found decr ...	1993	8308347
[the effect of water temperature on the action of bacterial insecticides against mosquito larvae].	the ld50 logarithm of bacillus thuringiensis and b. sphaericus toxins effects on the larvae of aedes aegypti and culex pipiens is in inverse correlation with the water temperature. the influence of the temperature on the toxins effect on c. pipiens larvae is higher than that for a. aegypti larvae. similarly, b. sphaericus toxin effect depends on the water temperature to a greater measure than that of b. thuringiensis toxin. the authors predict a high efficacy of b. sphaericus-based insecticides ...	1993	8336659
entomologic investigations of an epidemic of st. louis encephalitis in pine bluff, arkansas, 1991.	an epidemic of st. louis encephalitis (sle) occurred in jefferson county, arkansas during july-august 1991. at least 26 human cases were involved, with 25 cases in the town of pine bluff. twelve isolates of sle virus were obtained from mosquitoes collected in pine bluff between august 13 and 24: 11 from pools of culex pipiens quinquefasciatus, resulting in a minimum infection rate of 1.6 per 1,000 (n = 6,768) for this subspecies, and one isolate from a pool of 22 mosquitoes identified as cx. (cu ...	1993	8352390
temperature-related activity loss and mobility changes of esterases associated with insecticide resistance in culex pipiens mosquitoes.		1993	8369565
comparative inhibitory action of 4 standard bacteriophages on the larvicidal activity of certain mosquito pathogenic bacteria against culex pipiens larvae.	four bacteriophage (cp-51, cp-54, yousten-4 and yousten-14) were assayed against 7 entemopathogenic bacterial strains. the two cp ones, indicating variability of the host range of the tested phages which was suggested to be related to the environmental characteristics of the tested strains. on testing the susceptibility of 5 bacterial strains to the phage yousten-4 at different cultural ages, a correlation was found between incubation time and level of bacterial susceptibility to the tested phag ...	1993	8376850
a field survey of bacteriophage contamination of mosquito breeding places, inhibiting bacterial insecticide.	twelve geographically different mosquito breeding places were described and sampled for the detection of naturally existed bacteriophage viruses which could transduct and lysate 5 entomopathogenic bacteria. the surveyed places are classified into seepage, sewage, and irrigation breeding water. bacterial free filtrates of the collected samples were assayed against the tested bacteria in vitro and against 3rd instar culex pipiens larvae as well. nine out of the twelve places could demonstrate the ...	1993	8376856
rate of ingestion of culex pipiens (l.) larvae (diptera: culicidae) stimulated by nutritive substances.	relative rates of ingestion of fourth instar larvae of culex pipiens as indicated by the number of substrate filled gut segments per unit time were determined and compared after exposure to nutritive and inert particles. food particles with nutritive values (yeast; dried green algae, chlamydomonas reinhordtii; wheat flour; fishmeal and corn flour) were ingested approximately 3-4 times faster than inert particles (koalin, talk, charcoal and chalk). aqueous extracts of yeast or dried algae acceler ...	1993	8376871
respective role of the 42- and 51-kda components of the bacillus sphaericus toxin overexpressed in bacillus thuringiensis.	the 42- and 51-kda protein genes of bacillus sphaericus 1593 have been subcloned independently downstream from the cyta gene promoter of bacillus thuringiensis serovar israelensis and introduced into a non-mosquitocidal strain of bacillus thuringiensis. consequently, each protein was overproduced and accumulated as inclusion bodies which were purified. for the first time, the 42-kda protein inclusions alone were found to be toxic to culex pipiens larvae (lc50 at 48 h 300 ng ml-1); in contrast, t ...	1993	8384140
characterization and genetic organization of full-length copies of a line retroposon family dispersed in the genome of culex pipiens mosquitoes.	many full-length copies of a long interspersed repetitive element family, designated juan-c, are reiterated in the genome of culex pipiens mosquitoes. the complete juan-c elements have a length of 4.48 kb. they are terminated at one end with an adenosine-rich sequence preceded with an aataaa polyadenylation signal, lack terminal repeats and cause duplication of the host dna at the site of their integration. full-length juan-c copies display two long open reading frames potentially encoding two p ...	1993	8394766
[variations of free amino acids in hemolymph of culex pipiens pallens during overwintering period].	an analysis of the amino acids present in the hemolymph of culex pipiens pallens caught from resting or overwintering places (blood meal: sella 1, i.e. empty; ovary stage: under christophers iib) in zhengzhou (34 degrees 43'n, 113 degrees 39e) indicated that 19, 18 and 18 kinds of free amino acids (faas) were detected during stages of preoverwintering, overwintering and postoverwintering respectively. comparison of hemolymph amino acids between overwintering and preoverwintering stages revealed ...	1993	8403270
commensalism, adaptation and gene flow: mosquitoes of the culex pipiens complex in different habitats.	two ecotypes have been described for culex pipiens mosquitoes of the temperate zone: a human commensal type and a feral type, but their degree of evolutionary differentiation and taxonomic status are still unclear. the commensal form is characterized by life-history traits probably adaptive to underground man-made environments. this situation has sometimes been considered as an example of recent speciation although the existence of intermediate forms indicates that the balance between gene flow ...	1995	8522156
cloning and expression of a novel toxin gene from bacillus thuringiensis subsp. jegathesan encoding a highly mosquitocidal protein.	a gene, designated cry11b, encoding a 81,293-da crystal protein of bacillus thuringiensis subsp. jegathesan was cloned by using a gene-specific oligonucleotide probe. the sequence of the cry11b protein, as deduced from the sequence of the cry11b gene, contains large regions of similarity with the cry11a toxin (previously cryivd) from b. thuringiensis subsp. israelensis. the cry11b protein was immunologically related to both cry11a and cry4a proteins. the cry11b gene was expressed in a nontoxic s ...	1995	8534090
comparison of carbon dioxide, octenol and a host-odour as mosquito attractants in the upper rhine valley, germany.	field studies were conducted in the upper rhine valley to determine the responses of mosquitoes to cdc traps baited with either co2, octenol, light or paired combinations of these. among eight mosquito species caught, the attractant effect on trap catches was studied in the four most abundant: aedes vexans, ae.rossicus, ae.cinereus and culex pipiens. traps baited only with light or octenol caught few mosquitoes, whereas many were caught by traps baited with co2 alone or in combination with eithe ...	1995	8541587
mosquito productivity and surveillance for st. louis encephalitis virus in chicago during 1993.	the city of chicago's department of health monitors weekly deposition of egg rafts of culex species, prevalence of st. louis encephalitis (sle) virus-specific antibodies in feral birds, and prevalence of the virus in mosquito pools. the total number of culex egg rafts collected in 1993 (4,623) was 2-fold greater than for the 1992 mosquito season. virtually all of the early summer egg rafts were identified as culex restuans. after the week of july 18, culex pipiens accounted for 20-70% of the tot ...	1995	8551297
role of larval cadavers in recycling processes of bacillus sphaericus.	the influence of larval cadavers of culex pipiens on recycling processes of bacillus sphaericus was investigated by bioassays and spore counts in the laboratory. studies conducted with 3 different b. sphaericus concentrations (0.005, 0.01, 0.05 mg b. sphaericus/liter) indicated that the presence of cadavers in the water contributed to the maintenance of toxic levels of b. sphaericus. larval cadavers seem to contain all the nutrients necessary both for vegetative multiplication and for toxin synt ...	1995	8551302
detoxifying esterases in culex pipiens quinquefasciatus from the caribbean countries.	several over-produced esterases confer resistance to organophosphorus insecticides in the culex pipiens complex. we describe their distribution in islands and countries of the caribbean region based on new collections and previous studies, and discuss the need to: 1) undertake dna studies to correctly identify the esterase b alleles that are amplified in different regions, and 2) investigate the variability among gene copies within each amplification system in order to fully understand their ori ...	1995	8551309
characterization of the culex pipiens complex (diptera: culicidae) in madagascar.	morphological analysis of phallosome and multilocus electrophoresis were used to characterize populations of the culex pipiens l. complex from madagascar. samples phenotypically and genetically corresponding to cx. p. quinquefasciatus say were found on the east and west coasts, whereas, on the high plateau, 1 sample was composed mostly of phenotypical cx. p. pipiens l., genetically introgressed with quinquefasciatus at some loci (hbdh, aat-2, and hk-1). a hybrid zone between the 2 taxa was detec ...	1995	8551499
laboratory transmission of sindbis virus by aedes albopictus, ae. aegypti, and culex pipiens (diptera: culicidae).	the susceptibility of aedes albopictus (skuse) for sindbis (sin) virus was examined in the laboratory. ae. albopictus, ae. aegypti (l.), and culex pipiens (l.) became infected with and subsequently transmitted sin virus by bite to chicks after feeding on viremic 1-d-old chicks. after ingesting 10(5.3) plaque-forming units (pfu)/ml, ae. albopictus had the highest transmission rate (30%) of the 3 species. transmission by ae. aegypti was less efficient (7%), whereas none of the cx. pipiens transmit ...	1995	8551504
assessment of plant tissue feeding by sand flies (diptera: psychodidae) and mosquitoes (diptera: culicidae).	plant tissue feeding by culex pipiens molestus (forskål) was determined by identification of plant residues, differentially stained with calcofluor, in dissected mosquito guts. such residues were found in 42.3% of 286 field-caught mosquitoes. a method for determination of plant tissue feeding from specific sources is described. before feeding branches were suffused with calcofluor stain which binds to plant cell walls; stained residues of this tissue in the insect gut are indicative of feeding. ...	1995	8551514
characterization of six highly mosquitocidal bacillus thuringiensis strains that do not belong to h-14 serotype.	four strains belonging to bacillus thuringiensis serovars thompsoni, malaysiensis, canadensis, jegathesan and two auto-agglutinating b.t. strains were identified as being highly toxic to the mosquito larvae of the species aedes aegypti, anopheles stephensi, and culex pipiens. their larvicidal and hemolytic activities were determined and compared with those of strains known to be highly mosquitocidal and/or cytolytic from serovars of b.t. israelensis, morrisoni, darmstadiensis, medellin, kyushuen ...	1996	8555944
towards malaria control in nigeria: a qualitative study on the population of mosquitoes.	malaria is still highly prevalent in many tropical countries and this disease can only survive in areas where mosquitoes and infected human populations are high. relevant information on the species of mosquitoes, their habitats and their population are important in planning preventative strategies in the control of malaria, hence this study. mosquito species and their habitats were investigated in both high and low density areas of benin city, edo state, nigeria. the results showed that culex pi ...	1995	8568784
distribution and ecology of the mosquito fauna in the southwestern saudi arabia.	a mosquito larval survey was carried out in the southwestern region of saudi arabia for a two subsequent years period. nine mosquito species were identified; 4 anopheline species; anopheles arabiensis, an. sergentii, an. multicolor and an. tenebrosus and 3 culicine species, culex pipiens, cx. quinquefaciatus and cx. theileri as well as one aedine species, aedes caspius and culiseta subochrea. a map was made showing the distribution of the encountered species and a full description of all breedin ...	1995	8586876
vector competence of egyptian mosquitoes for rift valley fever virus.	reintroduction of rift valley fever (rvf) into egypt in 1993 raised concerns about the potential for egyptian mosquitoes to transmit the virus. we evaluated the ability of aedes caspius, culex pipiens, cx. antennatus, cx. perexiguus, cx. poicilipes, and anopheles pharoensis collected in the aswan area and cx. pipiens collected in the nile delta to transmit rvf virus. all mosquito species tested were susceptible to rvf virus infection, with an. pharoensis and ae. caspius being the most sensitive ...	1996	8619436
the midgut bacterial flora of wild aedes triseriatus, culex pipiens, and psorophora columbiae mosquitoes.	the midgut bacterial flora of wild-caught aedes triseriatus, culex pipiens, and psorophora columbiae mosquitoes was investigated. dissected midgut contents were examined using quantitative aerobic bacterial cultures. individual colonies (n = 134) were subcultured and identified to species. midgut bacterial counts changed dramatically during mosquito development. a 280-1,100-fold decrease in the bacterial population occurred between the larval stage and pupal emergence, whereas a subsequent 70-16 ...	1996	8619452
cloning and expression of the first anaerobic toxin gene from clostridium bifermentans subsp. malaysia, encoding a new mosquitocidal protein with homologies to bacillus thuringiensis delta-endotoxins.	a gene (cbm71) encoding a 71,128-da mosquitocidal protein (cbm71) was obtained by screening a size-fractionated xbai digest of total genomic dna from clostridium bifermentans subsp. malaysia ch18 with two gene-specific oligonucleotide probes. the sequence of the cbm71 protein, as deduced from the sequence of cbm71, corresponds to that of the 66-kda protein previously described as one of the mosquitocidal components of c. bifermentans subsp. malaysia. cbm71 shows limited similarities with bacillu ...	1996	8655486
phylogeny of fourteen culex mosquito species, including the culex pipiens complex, inferred from the internal transcribed spacers of ribosomal dna.	ribosomal dna sequence divergence in the internal transcribed spacer regions (its-1 and its-2) was examined for fourteen species and four subgenera (sixty-two clones) in the mosquito genus culex (diptera: culicidae). a neighbour-joining tree produced with kimura 2-parameter distances showed that each of the four subgenera was monophyletic at confidence probabilities of 70-99%. culex (lutzia) formed the sister group of cx. (culex). two major clades, a cx. pipiens complex-cx. torrentium assemblage ...	1996	8673266
[the attraction of the female urban mosquito culex pipiens (diptera, culicidae) for oviposition by different attractants].	for urban female mosquitoes to lay eggs, the following potential attractants were dark containers, larval feed, ammonia solutions, larval culture medium and hay infusion were tested. the latter was found to be the best attractant since it was the most attractive and cheaper. the combination of the attractants did not enhance their efficiency. it is recommended that egg traps should be used to detect and measure the number of the mosquitos. the possibility of suppressing the quantity of the urban ...	1996	8700008
short report: lack of virus replication in arthropods after intrathoracic inoculation of ebola reston virus.	to evaluate the potential for arthropods to serve as reservoir hosts of ebola virus, three mosquito species, aedes albopictus, aedes taeniorhynchus, and culex pipiens, and a soft tick, ornithodoros sonrai, were inoculated with 1o2.5 plaque-forming units of ebola reston virus. after incubation at 22 degrees c for 11 days, at least six specimens of each species were triturated and examined for evidence of viral replication by enzyme-linked immunosorbent assay and plaque assay. there was no evidenc ...	1996	8702028
host-parasite relationships of wuchereria bancrofti and mosquito hosts, culex pipiens l. and aedes caspius pallas.	we compared the defense mechanisms directed against wuchereria bancrofti by a filaria susceptible mosquito, culex pipiens, and a refractory one, aedes caspius. the reciprocal deleterious effects of both the mosquito host and its parasite are reported. anatomical and histological examinations of mosquitoes revealed minor differences in the general structure of the foregut of either species. the cibarial pump of ae. caspius, however, lacked a cibarial armature and damage inflicted to some of the m ...	1996	8721232
effect of ivermectin on survival and fecundity of culex pipiens the vector of wuchereria bancrofti in egypt.	the effect of two different doses of ivermectin on the survival and fecundity of culex pipiens was evaluated. female mosquitoes (50 in each group), same age and generation, were fed once on blood from ivermectin-treated rabbits. comparative treatments consisted of two different doses of ivermectin (0.1 mg or 0.4 mg/kg of body weight), and mosquito groups were fed on the rabbits at 3 days and 10 days post-treatment respectively. mosquitoes were maintained with 10% sucrose solution, at 25 degrees ...	1996	8721237
dominance of insecticide resistance presents a plastic response.	dominance level of insecticide resistance provided by one major gene (an insensitive acetylcholinesterase) in the mosquito culex pipiens was studied in two distinct environments. dominance level was found to be very different environments, varying from almost complete dominance to almost recessive when either propoxur (a carbamate insecticide) or chlorpyrifos (an organophosphorus insecticide) was used. to better understand this plastic response, three environmental parameters were manipulated an ...	1996	8722792
oviposition preferences of culex pipiens and culex restuans for infusion-baited traps.	the number of egg rafts oviposited by culex pipiens and culex restuans in infusion-baited ovitraps varied with the type of infusion substrate, infusion age, method of infusion preparation, and calendar date. in one or more tests, more culex egg rafts were collected from water infused with kentucky bluegrass sod, mixed grass clippings, straw, or a commercial rabbit chow than from a water control. infusions prepared with oak leaves, maple leaves, and sod soil were ineffective as culex oviposition ...	1996	8723254
contact toxicity of permethrin-impregnated military uniforms to culex pipiens (diptera:culicidae) and phlebotomus papatasi (diptera: psychodidae): effects of laundering and time of exposure.	the effects of laundering and time of exposure on the insecticidal activity of military uniform fabric impregnated with permethrin at 0.125 mg active ingredient (ai)/cm2 are reported from susceptibility tests with laboratory-reared mosquitoes, culex pipiens, and sand flies, phlebotomus papatasi. knockdown/mortality resulting from exposure of groups of female insects for periods of 1, 3, 5, 7, and 10 min was recorded and compared among 5 different treatment/wash groups (untreated/unwashed, treate ...	1996	8723263
organophosphate resistance in culex pipiens from cyprus.	populations of culex pipiens were sampled from 8 locations in cyprus between 1987 and 1993. all population samples generally revealed organophosphate resistance to malathion, temephos, chlorpyrifos, fenthion, dichlorvos, and pirimiphos methyl, in decreasing order of magnitude. of 7 populations assessed with the carbamate propoxur, all proved to be resistant to different degrees. of the 6 populations tested with permethrin, 2 were resistant to permethrin. resistance was associated with the presen ...	1996	8723267
attraction of aedes albopictus adults in sod infusion.	aedes albopictus adults were recovered from sod-baited gravid traps at 7 sites in 5 counties of southern and southwestern illinois in areas ranging from suburban to rural. the attraction of this species to a lure usually associated with members of the culex pipiens complex was investigated under laboratory and field conditions. olfactometer and oviposition preference tests in the laboratory showed that ae. albopictus is attracted to sod infusion and females readily oviposit on substrates in cont ...	1996	8723268
efficacy and persistence of altosid pellets against culex species in catch basins in michigan.	larvae of culex pipiens and cx. restuans in catch basins were exposed to altosid pellets (4% active ingredient, [s]-methoprene) applied at a rate of 11.3 kg/ha (7 g of pellets per catch basin). under field conditions, the pellets yielded an average 82% emergence inhibition of adult mosquitoes over the 15-wk trial period.	1996	8723274
uptake and development of wuchereria bancrofti in culex pipiens l. and aedes caspius pallas.	studies were conducted to compare early phenomena associated with w. bancrofti infection and further development in the filaria vector culex pipiens and the refractory mosquito aedes caspius. ingestion rates evaluated immediately after simultaneous feeding on an infected human were 69.1% for 43 cx. pipiens and 35.7% for 28 ae. caspius. the observed number of mf ingested by either mosquito did not vary significantly (2.7 +/- 1.4, and 2.3 +/- 0.9, respectively) and, based on the size of the blood ...	1996	8754640
sequence and secondary structure of the rdna second internal transcribed spacer in the sibling species culex pipiens l. and cx. quinquefasciatus say (diptera: culicidae).	the primary and secondary structure of the second internal transcribed spacer (its2) of ribosomal dna (rdna) of two members of the cx. pipiens complex, cx. pipiens and cx, quinquefasciatus, were examined in order to better understand the relationships between these two sibling mosquito species. the length of the sequenced rdna fragments was 512 bp (cx. pipiens) and 513 bp (cx. quinquefasciatus), including the its2 regions and flanking 5.8s-28s coding regions. the its2 sequences of cx. pipiens an ...	1996	8799736
larvicidal activity of bacillus thuringiensis natural isolates; indigenous to japan, against two nematoceran insect pests occurring in urban sewage environments.	a total of 1449 bacillus thuringiensis strains, indigenous to japan, were screened for larvicidal activity against two nematoceran insect pests, the mosquito, culex pipiens molestus (culicidae), and the moth-fly, telmatoscopus albipunctatus (psychodidae). mosquito specific strains were abundant in h serotypes 3abc (serovar kurstaki), 3ade (fukuokaensis), 4ac (kenyae), 7 (aizawai), 11ac (kyushuensis) and 29 (amagiensis), while moth-fly specific strains were predominantly found in h serotype 17 (t ...	1996	8817917
identification of endemic foci of filariasis by examination of mosquitoes for microfilariae.	studies were conducted in the nile delta of egypt to determine the feasibility of detecting wuchereria bancrofti microfilariae (mf) in mosquitoes as a primary surveillance method for the identification of filariasis-endemic villages. initial experimental studies evaluated the ingestion, survival, and migration rates of w. bancrofti mf in culex pipiens and culex antennatus after mosquitoes were fed on infected volunteers. in 2 villages, 1,684 bloodfed mosquitoes were dissected during the night im ...	1995	8825503
macroconditions of channel segments utilized by culex pipiens pallens immatures in saga city, southwest japan.	the relation between macroconditions of water channels and the breeding of culex pipiens pallens in saga city were examined, based on weekly census data over 3 years for ca. 2,000 channel segments. mosquito breeding activity was greatest in channel segments between building lots and field lots in the suburban area. the segments involved ranged from narrow roadside ditches (width < 1 m) to wide irrigation canals (width > 10 m), all of which were utilized by mosquitoes. there was a weak tendency f ...	1995	8825506
efficacy of ground ultra-low volume larvicidal treatments using temephos and bacillus thuringiensis var. israelensis against culex pipiens larvae.	spray drift determinations of truck-mounted ulv applications of temephos and bacillus thuringiensis var. israelensis (b.t.i.) in simulated field trials were conducted in the baix llobregat area near barcelona, spain, using larval culex pipiens as bioindicators. a 50:50 temephos:oil mixture applied at 350 ml/min, while traveling 9 kph, resulted in 100% control of larvae 10-50 m from the point of application (with the exception of 82% mortality at 30 m); control decreased rapidly to 50% at 55 m. m ...	1995	8825518
unconventional organization of amplified esterase b gene in insecticide-resistant mosquitoes of the culex pipiens complex.	the amplified esterase b gene responsible for resistance to organophosphorus insecticides in culex mosquitoes is shown to form a dna "puff" in salivary gland polytene chromosomes. this "puff" is absent in susceptible mosquitoes lacking the amplified gene, and unlike all puffs known today, it is neither related to development nor involved in protein synthesis. the "puff" therefore corresponds to a special arrangement of the very large number of copies (possibly up to 250,000) of the 25-30-kb dna ...	1996	8827593
physical and biological attributes of water channels utilized by culex pipiens pallens immatures in saga city, southwest japan.	physical and biological attributes of water channels utilized by immatures of culex pipiens pallens were studied in saga city, japan. water in mosquito-productive segments generally was stagnant or slowly running (mean < 5 cm/sec), with low and fluctuating dissolved oxygen concentrations and high electric conductivity. water flow > 20 cm/sec was considered necessary for prevention of mosquito breeding. the aquatic fauna in mosquito-productive segments was composed of taxa tolerable to polluted w ...	1996	8827594
role of dogs (canis domesticus) as hosts for african horse sickness virus.	at bet dagan culicoides imicola kieffer, c. schultzei gp. (a mammal feeder), culex pipiens l. (a laboratory vector) and culex univittatus theobald were found in significantly (p < 0.05) smaller numbers near dogs than near other hosts, while phlebotomus spp. were found in significantly (p < 0.05) higher numbers in dog kennels than in other animal houses. some 400 blood meals of culicoides spp. from israel and zimbabwe were negative for canine blood. only 1 of 16 blood meals of culex pipiens caugh ...	1996	8828119
the effects of opiates and opioid neuropeptides on mosquito hemocytes.	the effects of morphine, met-enkephalin, and its synthetic analogue dama on the hemocytes of culex pipiens mosquitoes were examined in vitro. morphine caused the cells to round up and decrease in area. met-enkephalin caused the cells to become ameboid and increase in area. this effect was accentuated with the addition of the neutral endopeptidase blocker phosphoramidon. dama caused a similar but greater enhancement of immune activation which was blocked by the opiate antagonist, naloxone. these ...	1995	8853704
existence of two acetylcholinesterases in the mosquito culex pipiens (diptera:culicidae).	two acetylcholinesterases (aches), ache1 and ache2, differing in substrate specificity and in some aspects of inhibitor sensitivity, have been characterized in the mosquito culex pipiens. the results of ultracentrifugation in sucrose gradients and nondenaturing gel electrophoresis of ache activity peak fractions show that each ache is present as two molecular forms: one amphiphilic dimer possessing a glycolipid anchor and one hydrophilic dimer that does not interact with nondenaturing detergents ...	1996	8863521
restriction analysis of the ribosomal dna internal transcribed spacer region of culex restuans and mosquitoes in the culex pipiens complex.	members of the culex pipiens linn. complex in the eastern, southern, and central united states are the primary vectors of st. louis encephalitis virus. although species and subspecies in the complex can be identified as 4th-instar larvae and by characters on the male genitalia, adult females cannot be identified accurately. in this study a ribosomal dna (rdna) segment that includes the internal transcribed spacer region (its) was amplified from culex pipiens pipiens linn., culex quinquefasciatus ...	1996	8887228
sensory aspects of host location in mosquitoes.	visual, thermal and olfactory stimuli all contribute to blood meal host location in mosquitoes but olfaction is probably the dominant sensory modality used for this purpose. much attention has been devoted to the l-lactic acid receptor because it is well characterized and because its sensitivity is a major determinant of host responsiveness in the anautogenous species aedes aegypti. studies employing statistical analysis of close to 500 single unit recordings and the scanning electron microscope ...	1996	8894299
an insensitive acetylcholinesterase in culex pipiens (diptera:culicidae) from portugal.	resistance mechanisms of a strain (praias) of northern house mosquito, culex pipiens l., collected in portugal in 1993, and highly resistant to organophosphates and carbamates, were investigated by comparing the resistance characteristics to 3 organophosphorous (temephos, chlorpyrifos, malathion) and 1 carbamate (propoxur) insecticides in the presence or absence of synergists; and by determining the possible occurrence of overproduced esterases or insensitive acetylcholinesterase (ache). the ref ...	1996	8913110
esterase polymorphism in insecticide susceptible populations of the mosquito culex pipiens.	gene amplification involving a particular haplotype has been found at the esterase b locus of mosquitoes from various countries. this similarity has been explained by a unique amplification event followed by migration and selection by organophosphate (op) insecticides. this assumes that the polymorphism of non-amplified esterase haplotypes is so large that the chance of independent amplification in two distinct populations is negligible. in order to test this assumption, three susceptible popula ...	1996	8919887
testing the unique amplification event and the worldwide migration hypothesis of insecticide resistance genes with sequence data.	in the mosquito culex pipiens, over-production of esterases is a common insecticide resistance mechanism. different alleles at the esterase a and b loci are known to occur in natural populations, as shown by enzyme electrophoresis and rflp studies on the esterase b locus. here we analyse the variability of the esterase a locus at the nucleotide level in mosquitoes possessing or lacking over-produced esterase a. a surprisingly high level of nucleotide polymorphism is found in coding and noncoding ...	1996	8939020
coamplification of esterase a and b genes as a single unit in culex pipiens mosquitoes.	in culex pipiens mosquitoes, resistance to organophosphorous insecticides often results from increased detoxification by two types of esterases, a and b, which are closely linked. overproduction of all esterase b so far investigated (b1, b2, b4, b5 and b6) is from gene amplification. an esterase a gene (esterase a2) has recently been cloned from mosquitoes with the overproduced esterases a2 and b2, and amplification of this gene has also been reported. we describe the cdna sequences of three add ...	1996	8939022