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topical mosquito repellents xiii: cyclic analogs of lactic acid.numerous cyclic analogs of lactic acid were synthesized to ascertain whether they might act as agonists of antagonists of lactic acid, a known attractant for mosquitoes. these compounds were evaluated with an in vitro blood-feeding test system and an in vivo cloth test. two of the compounds in the blood-feeding test system showed biphasic results, acting as attractants at low concentrations and as repellents at higher concentrations. several compounds (iii, v, vii, and x) repelled aedes aegypti ...19807359323
genetics and the origin of a vector population: aedes aegypti, a case study.thirty-four population samples representing the worldwide distribution of the mosquito aedes aegypti were analyzed for variation at 19 to 22 enzyme-coding genes. a multivariate discriminant analysis revealed that the genetic differences among populations in six geographic regions and between two subspecies enable one to determine the regional origin of a population. such studies of population genetics may have quite general applicability in studying vector-borne diseases.19807375945
the reinvasion of colombia by aedes aegypti: aspects to remember. 19807386716
aedes aegypti as a surrogate host for onchocerca spp. 19807386718
infection of aedes aegypti with onchocerca gutturosa. 19807410805
the urban mosquitoes of suva, fiji: seasonal incidence and evaluation of environmental sanitation and ulv spraying for their control.larval surveys and oviposition traps were used to monitor urban mosquito populations in two adjacent transects in suva, fiji between may 1978 and august 1979. populations of aedes aegypti and ae. pseudoscutellaris fluctuated seasonally with changes in rainfall, the latter species being most prevalent throughout the year. populations of these two species were highest between december and july and lowest between august and october. larval populations of culex quinquefasciatus did not show a season ...19807411679
a comparison of the number of multiple enzymatic forms in gravid and nongravid aedes aegypti (diptera: culicidae). 19807420365
yellow fever in the gambia, 1978--1979: epidemiologic aspects with observations on the occurrence of orungo virus infections.an epidemic of yellow fever (yf) occurred in the gambia between may 1978 and january 1979. retrospective case-finding methods and active surveillance led to the identification of 271 clinically suspected cases. a confirmatory or presumptive laboratory diagnosis was established in 94 cases. the earliest serologically documented case occurred in june 1978, at the extreme east of the gambia. small numbers of cases occurred in august and september. the epidemic peaked in october, and cases continued ...19807435793
yellow fever in the gambia, 1978--1979: entomological aspects and epidemiological correlations.an entomological survey was conducted in the gambia in january 1979, during the last phase of a yellow fever (yf) outbreak which began during the previous rainy season. in the dry conditions which prevailed in january, aedes aegypti was the only yf vector present. two yf virus strains were isolated from females of this mosquito species caught in a village of western gambia, where active human cases were documented. the ae. aegypti breeding sites were exclusively of the domestic type. larval indi ...19807435794
the presence of oviposition attractants of aedes albopictus larval holding water on aedes aegypti. 19807444586
malathion resistance in aedes aegypti of puerto rico induced by selection pressure on larvae.a high level of tolerance to malathion occurred in aedes aegypti larvae of san juan, puerto rico in 1978. the tolerance was 7-fold when compared with a susceptible strain. malathion selection pressure in the laboratory on this tolerant strain resulted in resistance after only six filial generations. the resistance of the f6 generation as 10-fold when compared with the strain as it was in the field in 1969, and 19-fold when compared with a susceptible laboratory strain. the results, together with ...19807446832
the genetic basis of susceptibility to infection with dirofilaria immitis in aedes aegypti. 19807458468
effects of two insect growth regulators on ecdysteroid production in aedes aegypti (diptera: culicidae).diflubenzuron and oms 2017 are insect growth regulators that affect larval to adult development in aedes aegypti (l.) by altering ecdysis. when larvae were exposed to sublethal concentrations, surviving adults express reduced reproductive potential. in mosquitoes, ecdysteroids are important in larval and adult ovarian development. we applied 30% emergence reduction concentrations (ei30) of oms 2017 and diflubenzuron to 4th-instar ae. aegypti to determine if changes in ecdysteroid production may ...19957473612
feeding the mosquito aedes aegypti with tmof and its analogs; effect on trypsin biosynthesis and egg development.female aedes aegypti that were given a blood meal by enema deposited yolk in their oocytes and synthesized trypsinlike enzymes in their midgut. when females were given an enema of aea-tmof (trypsin modulating oostatic factor) (nh2-ydpapppppp-cooh) and blood both egg development and trypsin biosynthesis were inhibited. similar results were observed if tmof was mixed with the blood meal and fed to female mosquitoes through a membrane. renin inhibitor (nh2-phpfhffvyk-cooh) or poly proline given by ...19957480877
aedes aegypti control in the lao people's democratic republic, with reference to copepods.an evaluation of the lao aedes aegypti control program and of the predatory abilities of copepods from vientiane, lao people's democratic republic was undertaken before a field release of copepods in thongkankam village, vientiane. copepods were transported to australia for evaluation of predatory abilities and their survival under various nutrient and ph conditions. mesocyclops guangxiensis was chosen for release over m. aspericornis due to its higher reproduction rate and its ability to surviv ...19957485682
a simulation model of the epidemiology of urban dengue fever: literature analysis, model development, preliminary validation, and samples of simulation results.we have developed a pair of stochastic simulation models that describe the daily dynamics of dengue virus transmission in the urban environment. our goal has been to construct comprehensive models that take into account the majority of factors known to influence dengue epidemiology. the models have an orientation toward site-specific data and are designed to be used by operational programs as well as researchers. the first model, the container-inhabiting mosquito simulation model (cimsim), a wea ...19957485707
isolation and identification of novel toxins from a new mosquitocidal isolate from malaysia, bacillus thuringiensis subsp. jegathesan.a new mosquitocidal bacillus thuringiensis subsp., jegathesan, has recently been isolated from malaysia. parasporal crystal inclusions were purified from this strain and bioassayed against fourth-instar larvae of culex quinquefasciatus, aedes aegypti, aedes togoi, aedes albopictus, anopheles maculatus, and mansonia uniformis. the 50% lethal concentration of crystal inclusions for each species was 0.34, 8.08, 0.34, 17.59, 3.91, and 120 ng/ml, respectively. these values show that parasporal inclus ...19957487029
non-linear dynamics of neurochemical modulation of mosquito oviduct and hindgut contractions.microphysiological techniques and computer-based methods of data acquisition and analysis were used to investigate the dynamics of neurochemical action on spontaneous contractions of continuously perfused oviducts and hindguts isolated from female mosquitoes (aedes aegypti). proctolin, leucomyosuppressin (lms), serotonin and octopamine, which are known to modulate insect muscle contractions, and a mosquito neuropeptide, aedes head peptide i (aea-hp-i), which inhibits host-seeking behavior, were ...19957490571
the apyrase gene of the vector mosquito, aedes aegypti, is expressed specifically in the adult female salivary glands.the yellow fever mosquito, aedes aegypti, expresses a gene, apyrase (apy), that encodes an atp-diphosphohydrolase. the product of this gene is a secreted enzyme that facilitates hematophagy by preventing platelet aggregation in the host. apy gene expression is limited to the cells of the distal-lateral and medial lobes of the adult female salivary glands. apyrase protein levels, detectable by antibodies, peak in the salivary glands about 4 days after adult emergence and remain high after a blood ...19957498420
two genes encoding midgut-specific maltase-like polypeptides from anopheles gambiae.full-length cdna clones of two genes have been isolated from the african malaria vector mosquito, anopheles gambiae. these genes, designated agm1 and agm2, encode maltase-like polypeptides of 498 and 599 residues, respectively. deduced amino acid sequences contain a putative signal peptide sequence and four potential glycosylation sites. agm1 and agm2 show highest similarities to the mal1 gene from aedes aegypti and three clustered maltase genes from drosophila melanogaster. both genes are locat ...19957498424
a factor xa-directed anticoagulant from the salivary glands of the yellow fever mosquito aedes aegypti.salivary gland extracts from the yellow fever mosquito aedes aegypti contain a factor xa-specific anticoagulant detectable in vitro by clotting assays. the anticoagulant is found only in female salivary glands, which is consistent with its role in bloodfeeding. extracts of adult female glands significantly delay both the prothrombin time and the activated partial thromboplastin time, but have no effect on the thrombin clotting time. the anticoagulant has been shown to result from the specific in ...19957498429
plasmodium gallinaceum: sporozoite invasion of aedes aegypti salivary glands is inhibited by anti-gland antibodies and by lectins.there is evidence which suggests that malaria sporozoites recognize mosquito salivary glands by specific receptor-ligand interactions. we are interested in identifying the putative salivary gland receptor(s) for sporozoite invasion. we used an in vivo bioassay for sporozoite invasion of salivary glands. in this assay, purified sporozoites from mature oocytes of plasmodium gallinaceum were injected into aedes aegypti mosquitoes and salivary glands were dissected at different time points after inj ...19957498430
aedes aegypti: a quantitative trait locus (qtl) influencing filarial worm intensity is linked to qtl for susceptibility to other mosquito-borne pathogens.because intensity of infection was significantly increased in a substrain of aedes aegypti selected for susceptibility to the filarial worm, brugia malayi, experiments were designed to assess numbers of microfilariae (mf) ingested and midgut penetration by mf in this susceptible substrain as compared to a refractory substrain selected from the same parental stock. refractory mosquitoes ingested significantly fewer mf than susceptible mosquitoes and significantly fewer numbers of mf penetrated th ...19957498432
plasmodium gallinaceum: mosquito peritrophic matrix and the parasite-vector compatibility.transmission of malaria parasites occurs by relatively few species of mosquitoes. one proposed mechanism of refractoriness is an inability of certain plasmodium spp. to cross the peritrophic matrix (pm) in the midgut of an incompatible mosquito. we have tested this hypothesis by studying sporogonic development of plasmodium gallinaceum in susceptible (aedes aegypti and anopheles gambiae g3) and refractory (anopheles stephensi) mosquito species in the presence and absence of the pm. in the presen ...19957498435
the salivary glands of the vector mosquito, aedes aegypti, express a novel member of the amylase gene family.several cdna clones with similarity to alpha-amylases have been characterized from a library made from adult female salivary gland rna isolated from the vector mosquito, aedes aegypti. the corresponding gene, designated amylase i (amy i), is expressed specifically in the proximal-lateral lobes of the adult female salivary gland, a pattern overlapping that of another gene, mal i, involved in carbohydrate metabolism. the deduced amino acid sequence of amy i indicates that this gene encodes a prote ...19937505701
dietary control of late trypsin gene transcription in aedes aegypti.in aedes aegypti the levels of midgut trypsin activity after feeding are directly proportional to the protein concentration in the meal. the mechanisms of this up-regulatory event were investigated by analyzing the expression of the late trypsin gene under different dietary conditions. transcription of the gene was dependent on both the quality and quantity of protein in the meal. as measured by northern blot analysis, the levels of late trypsin gene expression increased up to 100-fold 24 h afte ...19947519098
studies on the effect of translocation of chemical insecticides in eicchornia host plant on mansonia mosquitos--a potential control method.a novel method for the control of mansonia larvae was developed and tested. in this method, foliar absorption and translocation of a chemical insecticide, monocrotophos, a known systemic insecticide was studied in the eicchornia plant. acetone solution of the insecticide was painted onto leaves of the plant. at daily intervals, stems were severed and divided into equal sections which were introduced into bowls. larvae of aedes aegypti were tested for the presence of monocrotophos. it was found t ...19937526473
identification of damaged adult female specimens of aedes albopictus and aedes aegypti in the new world.two introduced species of aedes (stegomyia), aedes albopictus and aedes aegypti, occur in the new world. three characters, easily and simultaneously observed from an anteroventral view, allow for rapid and reliable specific identification of most specimens that lack the characteristic scutal scale patterns. these 3 characters are the presence or absence of pale scales on the clypeus; the presence or absence of a narrow, median line of pale scales on the anterior face of the midfemora; and the pa ...19947528784
unique specificity of in vitro inhibition of mosquito midgut trypsin-like activity correlates with in vivo inhibition of malaria parasite infectivity.synchrony in the egress of plasmodium ookinetes from the food bolus and enzymatic digestion of the blood meal in the mosquito midgut suggests that digestive enzymes play a role in the successful transmission of malaria parasites. previously, we found that parasite-produced chitinase is essential for parasite transmission and can be activated by mosquito midgut protease. to determine the suitability of developing a transmission-blocking vaccine directed against mosquito trypsin-like enzyme(s), ae ...19957534722
hemocyte alterations during melanotic encapsulation of brugia malayi in the mosquito armigeres subalbatus.the involvement of hemocytes in melanotic encapsulation reactions against brugia malayi was assessed in armigeres subalbatus. hemocyte populations, epitope changes, phenol oxidase (po) activity, and the presence of an 84-kda polypeptide were investigated in mosquitoes exposed to a b. malayi-infective bloodmeal (= immune-activated), in mosquitoes given a noninfective bloodmeal (= controls), in nonbloodfed mosquitoes (= naive), or in some combination of these. total hemocyte populations in immune- ...19957535848
resistance in some caribbean populations of aedes aegypti to several insecticides.thirty-four strains of aedes aegypti larvae from 17 caribbean countries were bioassayed for sensitivity to temephos, malathion, fenitrothion, fenthion, and chlorpyrifos. there were fairly high levels of resistance in tortola (10-12-fold resistance) and antigua (6-9-fold resistance) strains to temephos and to fenthion (tortola, 7-10-fold; antigua, 6-10-fold resistance). most other strains showed some resistance to malathion, fenitrothion, and chlorpyrifos, but only moderate levels. adult populati ...19957542312
improved medium for aedes aegypti tissue culture. 19957548955
analysis of a vitellogenin gene of the mosquito, aedes aegypti and comparisons to vitellogenins from other organisms.a genomic clone of the aedes aegypti vitellogenin a1 gene was sequenced including 2015 bp of 5' untranscribed sequence, 6369 bp of open reading frame interrupted by two introns, and a short 3' untranslated region. primer extension was used to identify the transcription initiation site. the amino termini of the large and small subunits were located by n-terminal sequencing of vitellin purified from eggs. the length of the signal sequence and the position of the cleavage site between the two subun ...19957550249
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 ...19957551198
effect of ethylene bis isobutyl xanthate isolated from a marine green alga dictyosphaeria favulosa on mosquito aedes aegypti. 19957558202
venezuelan equine encephalitis--colombia, 1995.an outbreak of venezuelan equine encephalitis (vee) that began in northwestern venezuela in april 1995 has spread westward to the guajira peninsula and to colombia (figure 1), resulting in an estimated minimum of 13,000 cases in humans and an undetermined number of equine deaths. governments of both countries have initiated efforts to control the spread of this outbreak by quarantining and vaccinating equines and applying insecticides. this report summarizes the ongoing investigation of the outb ...19957565549
full sequence and characterization of two insect defensins: immune peptides from the mosquito aedes aegypti.we report the complete amino acid sequence and biological activity of two immune peptides, from the yellow fever mosquito aedes aegypti, that are induced in response to infection. both peptides display biological activity against the gram positive microbe micrococcus luteus and substantial sequence homology to insect defensins, small heat-stable, antibiotic peptides previously described from several non-vector insects. these mosquito peptides, designated ae. aegypti defensins a and b, are isofor ...19957568275
aminopropeptide of human procollagen type i: a marker for the identification of blood from children in the mosquito blood meal.a capture enzyme-linked immunosorbent assay (elisa) to distinguish between blood from children and adults in the mosquito blood meal was examined using the alpha 1 chain of the aminopropeptide of human procollagen type i (pinp) as antigenic marker. rabbit anti-human pinp (alpha 1) antibody was used as catching antibody, and either normal serum from 288 african and 58 caucasian children and adults, or blood meals from 93 fed aedes aegypti, were examined. pinp in excess of 40 optical density units ...19957570897
post-inoculation changes in enzyme activity of aedes aegypti infected with chikungunya virus.levels of acetylcholinesterase, non-specific esterases, glutathione-s-transferase and glucose-6-phosphate dehydrogenase in aedes aegypti (l.) mosquitoes inoculated intrathoracally with chikungunya virus were elevated, as compared to uninoculated control insects. a number of these enzymes are important in the insects defence mechanism against xenobiotics, such as pesticides. malathion bioassays indicated a reduction in the susceptibility of experimentally injected insects with virus or virus-free ...19957572467
partial purification of plasma phenoloxidase of the yellow fever mosquito aedes aegypti l. (diptera: culicidae).a nitrocellulose-based assay was developed using a dot-blot apparatus to detect phenoloxidase activity in column fractions. using this assay, plasma phenoloxidase was partially purified from aedes aegypti larvae using hydrophobic interaction chromatography, gel filtration, and ion-exchange chromatography. the molecular weight (m(r)) native enzyme was 130,000, and it contained subunits of 76,000, 62,000, and 58,000. two phenoloxidase peaks were observed by ion exchange chromatography, and these f ...19957584838
control of mosquito breeding using wood scrapings treated with neem oil.wood scrapings were given shape of a ball and soaked in 5, 10 and 20% neem (azadirachta indica) oil diluted in acetone. control of anopheles stephensi and aedes aegypti breeding in water storage overhead tanks (ohts) with the application of these balls was achieved for 45 days. two balls soaked in 5% neem oil produced the best results among other concentrations tested.19957589730
laboratory evaluation of a new repellent camouflage face paint.a combined formulation of the u.s. army's camouflage face paints and the new extended duration topical insect/arthropod repellent was tested on human volunteers to determine repellency and duration of protection (2-12 h) against aedes aegypti and anopheles stephensi. under laboratory conditions (27 degrees c and 80% rh), the face paint/repellent formulation provided > or = 95% repellency or better for up to 6 h for ae. aegypti and 8 h for an. stephensi. an analysis of variance showed no signific ...19957595441
impact of deltamethrin-impregnated bednets on biting rates of mosquitoes in zaire.in a rural area of zaire, the whole population of a village was protected by deltamethrin-impregnated mosquitoes bednets. a similar village was observed as a control. biting rates for mosquitoes were recorded in both villages. the principal man-biting species were mansonia africana, mansonia uniformis, and aedes aegypti. in the village protected by the impregnated mosquito bednets, the number of mansonia bites was reduced 96% indoors and at a lesser rate outdoors. biting rates of ae. aegypti dro ...19957595444
aedes albopictus and other aedes (stegomyia) species in fiji.during an assessment of the dengue situation in fiji in early 1992, a house-to-house survey of container-breeding aedes was made. discarded tires and water drums were identified as key breeding sites for the 4 potential dengue vectors: aedes aegypti, aedes albopictus, aedes pseudoscutellaris, and aedes polynesiensis. aedes albopictus were detected on viti levu, vanua levu, and on taveuni. examination of early records and of used tire importation suggests entry into fiji after july 1985 but well ...19957595450
gene for cytochrome c oxidase subunit ii in the mitochondrial dna of culex quinquefasciatus and aedes aegypti (diptera: culicidae).the cytochrome c oxidase subunit ii (coii) gene between transfer rna for leu and lys in the mitochondrial dna of culex quinquefasciatus say and aedes aegypti (l.) was amplified by the polymerase chain reaction (pcr) technique. both the gene order and direction of transcription were identical to anopheles and drosophila. nucleotide sequences of the pcr-amplified coii genes in these two mosquitoes exhibited 88% homology, and the frequency of transition was very close to that of transversion. the h ...19957608924
risk factors for dengue infection during an outbreak in yanes, puerto rico in 1991.in november 1991, during a five-month dengue outbreak, we performed epidemiologic and serologic surveys linked to an earlier entomologic study in a community of 425 houses in yanes (florida), puerto rico. we obtained a household response rate of 95% (98 of 103) and blood samples from 84% (345 of 410) of the participants. dengue incidence, as volunteered by the respondents, was 5% (21 of 410), but serologic diagnosis (immunoglobulin m and igg-enzyme-linked immunosorbent assays [elisa]) indicated ...19957611553
dna sequence and site of mutation of the gaba receptor of cyclodiene-resistant red flour beetle, tribolium castaneum.using polymerase chain reactions (pcr) on cdna, the dna sequence of a membrane spanning region of a gaba receptor of the red flour beetle, tribolium castaneum was identified. the deduced amino acid sequence indicates that its basic structure is similar to the gaba receptor of rdl type subunits of drosophila melanogaster and of blattella germanica. particularly conserved are m1, m2 and m3 segments. within this 146 amino acid stretch, the gaba receptor from the red flour beetle differed from corre ...19957613764
insect repellent formulations of n,n-diethyl-m-toluamide (deet) in a liposphere system: efficacy and skin uptake.novel formulations for a deet in liposphere microdispersion in the form of lotion were prepared from natural solid triglycerides and phospholipids dispersed in buffer solution. the formulations containing 6.5, 10, and 20% deet were effective as a repellent against the common aggressive biting mosquitoes, aedes aegypti and anopheles stephensi, for up to 6 h. the acute dermal absorption of the 10% loaded formulation was conducted in rabbits using 14c-labeled deet. 14c-labeled deet, 10% in alcohol ...19957616186
relationship between cold hardiness and supercooling point in aedes albopictus eggs.for many insects, low temperatures are not lethal unless their tissues freeze. to determine whether freezing is the cause of low temperature mortality of aedes albopictus eggs, we measured their lower lethal temperature, the temperature that causes 50% mortality in a population, and supercooling point, the temperature at which the tissues freeze. tropical and temperate ae. albopictus eggs were tested under different diapause and cold acclimation conditions. temperate ae. albopictus eggs had a lo ...19957616187
an immunological factor that affects anopheles gambiae survival.high titers of antibodies against anopheles gambiae midguts were produced in new zealand rabbits to identify midgut targets for an antimosquito vaccine. the serum from one of 8 rabbits (designated r2b6) killed 71.6% (abbott's adjusted % mortality) of an. gambiae within 7 days. mosquitoes ingesting r2b6 serum were unable to absorb their blood meal nutrients, resulting in reduced oviposition and egg hatching rates. anopheles stephensi and anopheles arabiensis were also killed when ingesting r2b6 s ...19957616189
field evaluation of alphacypermethrin and lambda-cyhalothrin against aedes aegypti and aedes albopictus in malaysia.alphacypermethrin (fendona) and lambda-cyhalothrin (icon) were evaluated against sentinel bloodfed adults and 4th-instar larvae of aedes aegypti in a housing estate in malaysia. the impact of both pyrethroids on field populations of ae. aegypti and aedes albopictus were monitored weekly using oviposition trap samples. both alphacypermethrin and lambda-cyhalothrin showed adulticidal and larvicidal effects.19957616191
mosquito vitellogenin receptor: purification, developmental and biochemical characterization.vitellogenin receptors (vgrs) play a critical role in egg development of oviparous animals by mediating endocytosis of the major yolk protein precursor, vitellogenin. a modification of the method for extracting the mosquito (aedes aegypti) vgr from ovary membranes resulted in an 11-fold higher yield and 56-fold increase in relative purity of the vgr, in turn permitting purification, antibody production, and microsequencing. a kd of 15 nm was estimated from binding assays for the enriched vgr, in ...19957633468
insect immunity: isolation of three novel inducible antibacterial defensins from the vector mosquito, aedes aegypti.the injection of escherichia coli and micrococcus luteus into the hemocoel of aedes aegypti induces a potent antibacterial activity in the hemolymph. we have purified and fully characterized three 40-residue antibacterial peptides from the hemolymph of bacteria-challenged mosquitoes that are absent in naive mosquitoes. the peptides are potently active against gram-positive bacteria and against one of the gram-negative bacteria that were tested. the amino acid sequences clearly show that the thre ...19957633471
cloning, sequencing and functional expression of an acetylcholinesterase gene from the yellow fever mosquito aedes aegypti.a degenerate pcr strategy was used to isolate a fragment of the acetylcholinesterase gene (ace) homolog from aedes aegypti and screen for a cdna clone containing the complete open reading frame of the gene. the predicted amino acid sequence of the aedes gene shares 64% identity with ace from drosophila and 87% identity with the acetylcholinesterase gene from another mosquito species anopheles stephensi. high levels of expression of the aedes gene were achieved by infection of sf21 cells with a r ...19957635199
laboratory evaluation of an ovipositional trap for mosquito adults aedes aegypti (l.) (diptera: culicidae).a trap was designed, fabricated and evaluated for trapping and killing ovipositing females of the yellow fever mosquito aedes. aegypti. water in which larval stages had previously dwelt for 48 hrs. formed the attractant source for ovipositing mosquito females. the trap was evaluated under different experimental conditions. single choice and double choice experiments were performed with or without glue applied to inner surfaces, to determine trap efficacy. effect of population size and alteration ...19957636150
dengue in french guiana, 1965-1993.while it seems likely that dengue fever (df) has existed in french guiana for at least one century, data on outbreaks are sketchy before temporary eradication of the dengue vector mosquito aedes aegypti and its reestablishment in the early 1960s. dengue cases were serologically confirmed for the first time in 1965, and since then dengue epidemics have occurred at two to six year intervals, the most important occurring in 1968-1969, 1970, 1972, 1976, 1982, 1986, and 1992. three of the four dengue ...19957640693
molecular cloning of a major cockroach (blattella germanica) allergen, bla g 2. sequence homology to the aspartic proteases.inhalation of allergens produced by the german cockroach (blattella germanica) elicits ige antibody formation and the development of asthma in genetically predisposed individuals. we compared the allergenic importance of two cockroach (cr) allergens, bla g 1 and bla g 2, and determined the complete amino acid sequence of the major 36-kda allergen, bla g2. a survey of 106 sera from cr allergic patients showed the prevalence of ige antibodies to bla g 1 and bla g 2 to be 30.2% and 57.6%, respectiv ...19957642642
age and body size effects on blood meal size and multiple blood feeding by aedes aegypti (diptera: culicidae).ten-day-old, parous aedes aegypti (l.) had a higher threshold of blood meal size for the inhibition of continued host-seeking than did 5 d-old, nulliparous females of the same size. older females of a smaller-bodied cohort had a higher threshold of blood meal size for the initiation of egg development than did younger females. in contrast, older larger-sized females had a lower blood meal-size threshold for egg development. the blood of paired avian hosts was marked with rubidium and cesium to s ...19957650708
edhazardia aedis (microspora: culicosporidae) effects on the reproductive capacity of aedes aegypti (diptera: culicidae).the influence of the microsporidium edhazardia aedis (kudo) on the survival and reproduction of its mosquito host, aedes aegypti (l.), was studied in the laboratory. survival, fecundity, egg hatch, and percentage of emergence for 4 gonotrophic cycles were compared for control and infected mosquitoes. control females oviposited an average of 123.1 eggs over 4 gonotrophic cycles, 86.1% of which hatched, whereas infected females laid an average of 38.0 eggs with a 69.3% hatch. emergence in progeny ...19957650718
spread of aedes albopictus and decline of ae. aegypti (diptera: culicidae) in florida.waste tires and other types of artificial containers were sampled for immature aedes to monitor changes in the occurrence of aedes aegypti (l.) and aedes albopictus (skuse) in florida. the initial invasion and spread of ae. albopictus in florida occurred in the northern part of florida. throughout this region, major declines in the abundance of ae. aegypti have been associated with the expansion of ae. albopictus in both urban and rural areas. generally, the same results have occurred in central ...19957650719
isolation and characterization of mosquito ferritin and cloning of a cdna that encodes one subunit.ferritin, an iron storage protein, was isolated from larvae and pupae of aedes aegypti grown in an iron-rich medium. mosquito ferritin is a high molecular weight protein composed of several different, relatively small, subunits. subunits of molecular mass 24, 26, and 28 kda are equally abundant, while that of 30 kda is present only in small amounts. the n-terminal sequence of the 24 and 26 kda subunits are identical for the first 30 amino acids, while that of the 28 kda subunit differs. studies ...19957655055
population interaction of toxorhynchites splendens and aedes aegypti (diptera: culicidae) in the laboratory.population interaction of toxorhynchites splendens and aedes aegypti in relation to the complexity of the breeding habitats and their initial number was studied in the laboratory. the predator and the prey were introduced in different ratios in the colony cages (1 m3) with different oviposition structures. predator-prey interaction lasted for 5-9 weeks without structural complexity of the oviposition containers. when there was a structural complexity, their interaction lasted for 18 weeks. durin ...19947667726
larvicidal potential of five philippine plants against aedes aegypti (linnaeus) and culex quinquefasciatus (say).five species of philippine plants, reported in the literature to have insecticidal properties, were selected for investigation, namely: anona squamosa ("atis" or sugar apple), eucalyptus globulus ("bagras" or olive gum eucalyptus), lansium domesticum ("lansones"), azadirachta indica ("neem") and codiaeum variegatum ("san francisco" or croton). these were screened and assayed for their larvicidal potential against aedes aedes aegypti (linnaeus) and culex quinquefasciatus (say) by exposing 3rd-4th ...19947667727
hirsutellin a, a toxic protein produced in vitro by hirsutella thompsonii.a toxic protein, hirsutellin a, has been purified from the mite fungal pathogen, hirsutella thompsonii, using ammonium sulphate precipitation, ion exchange chromatography and gel filtration on bio-gel p-10. the protein has been characterized as a monomer with a molecular mass of 15 kda and an isoelectric point of 10.5. the amino acid composition and the n-terminal sequence of hirsutellin a (34 amino acids) have been determined. from these results, the toxin appears to be distinct from other know ...19957670635
electrophysiological responses of receptor neurons in mosquito maxillary palp sensilla to carbon dioxide.sensilla basiconica on the maxillary palps of female aedes aegypti contain a receptor neuron which produces a phasic-tonic pattern of action potential response to low concentrations (150-300 ppm) of carbon dioxide (co2), a stimulus known to be involved with host seeking behavior. these receptor neurons respond reliably to small increments in co2 concentration (e.g., 50 ppm). we were particularly interested in evaluating the possibility that the sensitivity to step increases in co2 concentration ...19957674195
community participation in dengue prevention and control: a survey of knowledge, attitudes, and practice in trinidad and tobago.the priorities of public health planners are often at variance with the community's own environmental sanitation priorities and perspectives. public opinion about individual, collective, and governmental responsibilities in addressing these issues and priorities is of particular importance when designing community-based programs. in a study conducted in trinidad and tobago on knowledge, attitudes, and practice regarding dengue, its prevention and control, a high level of awareness about dengue a ...19957677210
extracts of mosquito salivary gland inhibit tumour necrosis factor alpha release from mast cells.extracts of salivary glands of the yellow fever mosquito aedes aegypti inhibit tumour cell-stimulated release of tumour necrosis factor alpha (tnf alpha) from rat mast cells, but do not inhibit antigen-induced histamine secretion. this inhibitory activity for tnf alpha is found in salivary glands of female but not in male mosquitoes. this inhibition is not mediated by bacterial contamination (lps), by calcitonin gene related peptide (cgrp), nerve growth factor (ngf), epidermal growth factor (egf ...19937679483
ultra-rapid, simple, sensitive, and economical silica method for extraction of dengue viral rna from clinical specimens and mosquitoes by reverse transcriptase-polymerase chain reaction.a rapid, simple and efficient single-tube procedure is described for the isolation of dengue virus rna from small amount of serum (10 microliters) followed by a reverse transcriptase-polymerase chain reaction (rt-pcr). recovery of rna is based on the lysing and nuclease-inactivating properties of guanidinium thiocyanate in the presence of silica. the silica rt-pcr can be completed within 5 hours starting from rna extraction to agarose gel electrophoresis. all of the 63 dengue-3 culture-positive ...19937689635
blood-feeding behavior of dengue-2 virus-infected aedes aegypti.this study was designed to determine if infection of aedes aegypti with dengue-2 virus affects the ability of the mosquito to efficiently locate and imbibe blood from an uninfected host. previous studies suggest that some parasites manipulate their arthropod host to increase the probability of transmission by interfering with blood-feeding efficiency. we found no evidence that dengue-2 virus infection by intrathoracic inoculation impaired the blood-feeding efficiency of ae. aegypti. we speculate ...19957694963
proportions of eggs laid by aedes aegypti on different substrates within an ovitrap in trinidad, west indies.ovitraps were exposed outdoors during wet and dry seasons in trinidad to determine the proportions of eggs laid on three substrates: the widely-used hardboard 'paddle' (p), the water surface (w) and the inside surface of the ovitrap wall (s) in three types of blackened ovitrap: round, glass (rg), round, plastic (rp) and rectangular, plastic (sp). of the 3556 eggs obtained, most (86.4%) were laid during the wet season when statistically significant differences were detected between substrates but ...19957696690
ovariolar 'basal body' development and physiological age of the mosquito aedes aegypti.dissection of the ovaries of the mosquito aedes aegypti (diptera: culicidae) revealed, in each ovariole, a group of seven to nine specialized epithelial cells in a region of the calyx wall that is enclosed by the end of the ovariolar sheath. this group of cells is termed the basal body. during ovulation, the mature oocyte passes from the ovariole into the calyx lumen through the basal body. subsequently, granulation occurs in the basal body cells. the granular basal bodies differ from all previo ...19957696694
dopachrome conversion activity in aedes aegypti: significance during melanotic encapsulation of parasites and cuticular tanning.phenol oxidase (po) and dopachrome conversion enzyme (dce) were partially purified from aedes aegypti larvae by ammonium sulfate fractionation. po from a. aegypti functions in the hydroxylation of monophenols (e.g., tyrosine and tyramine) to their related o-diphenols, and the oxidation of o-diphenols (e.g., l-dopa, dopamine, n-acetyldopamine) to their respective o-quinones. partially purified dce showed high specificity toward dopachrome generated from dopa with the l-configuration. the combined ...19947703986
functional expression of insecticide-resistant gaba receptors from the mosquito aedes aegypti.we are interested in cloning insecticide resistance genes from vector mosquitos for use as selectable markers in their genetic transformation. as a first step towards this goal, we here report the functional homomultimeric expression of a gamma-aminobutyric acid (gaba) receptor subunit gene, resistance to dieldrin (rdl), from the yellow fever mosquito aedes aegypti in baculovirus-infected insect cell lines. replacement of alanine296 with a serine leads to approximately 100-fold insensitivity to ...19947704314
evaluation of the laboratory mouse model for screening topical mosquito repellents.eight commercial repellents were tested against aedes aegypti 0 and 4 h after application in serial dilution to volunteers and laboratory mice. results were analyzed by multiple regression of percentage of biting (probit scale) on dose (logarithmic scale) and time. empirical correction terms for conversion of values obtained in tests on mice to values expected in tests on human volunteers were calculated from data obtained on 4 repellents and evaluated with data obtained on 4 others. corrected v ...19947707065
aedes albopictus in muzquiz city, coahuila, mexico.aedes albopictus was found in m. muzquiz, coahuila, mexico, in the summer of 1993. aedes albopictus larvae were collected in tires and bottles at low density. aedes aegypti, toxorhynchites theobaldi, culex quinquefasciatus, and culiseta incidens were collected in the same containers.19947707068
the effect of multiple host contacts on the infectivity of dengue-2 virus-infected aedes aegypti.this study was designed to determine if transmission rates for dengue-2 virus by aedes aegypti are altered by mosquitos probing a host for blood or imbibing blood prior to attempting transmission. aedes aegypti is known to contact multiple hosts during each egg-laying cycle and multiple host contacts might diminish the amount of virus in infected mosquito's salivary glands or ducts and render them functionally uninfective. probing a host 5, 10, or 20 consecutive times did not significantly alter ...19957707190
mosquito ecdysteroid receptor: analysis of the cdna and expression during vitellogenesis.an insect steroid hormone, 20-hydroxyecdysone (20e), plays an important role in regulating egg maturation in mosquitoes. to better understand its role, we cloned the cdna coding for the putative ecdysteroid receptor from the mosquito, aedes aegypti (aaecr). the 4158 bp aaecr cdna has an open reading frame of 675 amino acids with 10 potential glycosylation sites and a putative phosphorylation polyserine domain. the aaecr has a dna binding domain with two zinc fingers and a ligand binding domain c ...19957711747
early trypsin activity is part of the signal transduction system that activates transcription of the late trypsin gene in the midgut of the mosquito, aedes aegypti.trypsin activity during the first hours after feeding is essential to induce late trypsin gene expression. these results are consistent with the idea that free amino acids or other products released during digestion might be the initial signal for transcriptional activation of late trypsin. besides early trypsin, some other factor(s) have to be translated for induction of late trypsin. this is the first case in which the proteolytic activity of a digestive enzyme is part of the signal transducti ...19957711754
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.19957719881
[aedes albopictus and aedes aegypti at ile de la réunion].aedes albopictus and aedes aegypti are both found on the island. the former, being the probable vector of dengue on the island, is highly anthropophilic. it breeds in domestic environments as well as in natural breeding sites. the latter has a more restricted distribution and is never anthropophilic. larvae of ae. aegypti are only found in natural habitats, always associated with ae. albopictus, but in small proportions. such an ecology and behaviour for the typicus form of ae. aegypti are abnor ...19947726666
brugia pahangi: the effects of cecropins on microfilariae in vitro and in aedes aegypti.synthetic cecropins, antibacterial peptides from insect haemolymph, have been tested for their ability to attenuate the motility of microfilariae of the filarial nematode brugia pahangi in an in vitro assay. fifty micromolar concentrations of these peptides, equivalent to physiological concentrations in immune-stimulated insects, cause significant attenuation of motility compared with untreated microfilariae. similar results were obtained with cecropins a and b. this is the lowest concentration ...19957729475
indirect control of yolk protein genes by 20-hydroxyecdysone in the fat body of the mosquito, aedes aegypti.in response to a blood meal, the fat body of the female mosquito, aedes aegypti, begins massive production of several yolk proteins which are subsequently stored in the developing oocytes. although 20-hydroxyecdysone (20e) is important for initiation and maintenance of expression of the yolk protein genes encoding vitellogenin (vg) and vitellogenic carboxypeptidase (vcp), the exact nature of 20e action has not been clearly defined. a primary question is whether this hormone directly stimulates e ...19957742832
comparative linkage maps for the mosquitoes, aedes albopictus and ae. aegypti, based on common rflp loci.aedes albopictus and aedes aegypti are members of the mosquito family culicidae and share a haploid chromosome complement of three. although a genetic linkage map based on restriction fragment length polymorphism (rflp), markers exists for ae. aegypti, the extent of synteny and linkage order conservation between the two species was unknown. a comparative linkage map for ae. albopictus was constructed based mainly on cdna clones from ae. aegypti. nearly all ae. aegypti probes hybridized to ae. al ...19957742975
comparison of migration and encapsulation of brugia malayi microfilariae from the midgut to the hemocoel between anopheles quadrimaculatus and aedes aegypti.comparisons were made of migration and encapsulation of ingested sheathed microfilariae of brugia malayi from the midgut into the hemocoel between anopheles quadrimaculatus (refractory and susceptible strains to b. malayi) and aedes aegypti (black-eyed, liverpool strain susceptible to b. malayi). encapsulation and melanization of microfilarial sheaths and microfilariae occurred in both strains of an. quadrimaculatus and in ae. aegypti. in both strains of an. quadrimaculatus, by 4 hr and by 24 hr ...19957745283
mosquito larvicidal activity of escherichia coli with combinations of genes from bacillus thuringiensis subsp. israelensis.the genes cryiva and cryivd, encoding 134- and 72-kda proteins, respectively, and the gene for a regulatory 20-kda polypeptide of bacillus thuringiensis subsp. israelensis (serovar h14) were cloned in all seven possible combinations by the escherichia coli expression vectors pt7 and puhe. the four combinations containing cryiva (cryiva alone, with cryivd, with the 20-kda-protein gene, and with both) displayed high levels of mosquito larvicidal activity in puhe. the toxicity of the combination of ...19957751296
dengue serologic survey in ribeirão preto, são paulo, brazil.the city of ribeirão preto suffered a dengue 1 epidemic that began in november 1990 and ended in march 1991. a serologic survey designed to detect igg antibodies to the four dengue serotypes and other flaviviruses was carried out in ribeirão preto during september and october of 1992. dengue 1 antibodies were detected in 5.4% of the survey participants. significantly higher seropositivity (9.3%) was found among subjects residing in the northwest sector of ribeirão preto than among those living i ...19957757124
isolation of antifungal and larvicidal constituents of diplolophium buchanani by centrifugal partition chromatography.three phenylpropanoids, myristicin [1], elemicin [2], and trans-isoelemicin [3], together with two furanocoumarins, oxypeucedanin [4] and oxypeucedanin hydrate [5], have been isolated from the leaves of diplolophium buchanani by a separation strategy involving the almost exclusive use of centrifugal partition chromatography. all five compounds were antifungal in a tlc bioautography test using cladosporium cucumerinum. compounds 1-4 exhibited larvicidal activity against aedes aegypti.19957760070
antibacterial peptides in insect vectors of tropical parasitic disease.the induction and characterization of immune peptides in two groups of medically important insects, the mosquitoes and blackflies, is currently an important research area. mosquitoes transmit a variety of viral and parasitic diseases including yellow fever, dengue, malaria and lymphatic filariasis. simuliid black flies are vectors of river blindness. the diseases are together responsible for death and morbidity in millions of people each year. the relationship between inducible peptides and bact ...19947768149
transient expression of a promoter-reporter construct in differentiated adult salivary glands and embryos of the mosquito aedes aegypti.vector-borne pathogens develop in close association with specific tissues in their insect hosts. efforts are being made to characterize insect genes that are expressed in tissues that have important roles in pathogen propagation. successful transfection and expression of exogenous genes in terminally differentiated tissues of insects has previously proven difficult. here we report a method that should allow the analysis of genes that are expressed in adult tissues and organs. transient expressio ...19957771613
effect of sublethal dosages of insecticides on chikungunya virus susceptible and refractory strains of aedes aegypti.three strains of aedes aegypti mosquitos viz (i) crs, refractory to chikungunya (chik) virus by oral route of infection but susceptible to ddt (2) css, susceptible to chik virus and also susceptible to ddt (3) css-ddtr, susceptible to chik virus but resistant to ddt, were examined for the effect of sublethal dosages of ddt and deltamethrin on their fecundity. biochemical analysis showed that there was an increase in glutathione s-transferase activity in the css-ddtr strain which was associated w ...19947777922
breeding of aedes aegypti (l.) and aedes albopictus (skuse) in urban housing of sibu town, sarawak.an aedes survey using various larval survey methods was conducted in 12 urban housing areas and 29 vacant lands in sibu town proper. aedes albopictus larvae were found in all areas surveyed while aedes aegypti larvae were present in 10 localities and 4 vacant lands. there were no significant difference in the house index, breteau and larval density index of these two aedes (stegomyia) species from the survey areas. the proportion of containers positive with ae. aegypti and ae. albopictus in area ...19947777923
[deficiency in public services and breeding of aedes aegypti in venezuela]. 19957786414
characterization of a salivary gland-specific esterase in the vector mosquito, aedes aegypti.esterase enzymatic activity was investigated in salivary gland lysates of adult aedes aegypti. esterases in lysates made from female glands had higher specific activity than those in lysates from male glands towards beta-naphthyl acetate but showed no difference with alpha-naphthyl butyrate as a substrate. female salivary gland lysates showed no difference in activity to alpha- and beta-forms of naphthyl acetate and no discernable activity towards alpha-naphthyl caprate. both female and male sal ...19957787844
restriction fragment length polymorphism mapping of quantitative trait loci for malaria parasite susceptibility in the mosquito aedes aegypti.susceptibility of the mosquito aedes aegypti to the malarial parasite plasmodium gallinaceum was investigated as a quantitative trait using restriction fragment length polymorphisms (rflp). two f2 populations of mosquitoes were independently prepared from pairwise matings between a highly susceptible and a refractory strain of a. aegypti. rflp were tested for association with oocyst development on the mosquito midgut. two putative quantitative trait loci (qtl) were identified that significantly ...19957789771
culekinin depolarizing peptide: a mosquito leucokinin-like peptide that influences insect malpighian tubule ion transport.a peptide termed culekinin depolarizing peptide (cdp) was isolated from approximately 1.2 million mosquitos (94% culex salinarius). the peptide was isolated on the basis of a rapid myotropic assay that utilized a hindgut preparation from leucophaea maderae and a transepithelial voltage assay that used mosquito malpighian tubules from aedes aegypti. a 15% trifluoroacetic acid extraction from the mosquitos, two solid phase extraction steps, and six hplc steps resulted in the isolation of 9.7 nmol ...19947800855
aquatic safety of lagenidium giganteum: effects on freshwater fish and invertebrates.eleven freshwater species were exposed to a zoosporeproducing fungus, lagenidium giganteum, with the goal of determining species sensitivity with standard and new test procedures. the tests included standard, 4-day acute exposures of cladocerans (ceriodaphnia dubia, daphnia pulex, and d. magna) and the fathead minnow (pimephales promelas). standard 7-day chronic exposures of c. dubia and a 7-day embryo-larval exposure of p. promelas were also conducted. new, 4-day acute, methods were developed f ...19947806894
utilization of bloodfed females of aedes aegypti as a vehicle for the transfer of the insect growth regulator pyriproxyfen to larval habitats.bloodfed female aedes aegypti were exposed to a surface treated with pyriproxyfen at 1.0 g m2 for 30 min and then allowed to lay eggs in cups of water containing 4th-instar larvae. adult emergence from the immatures was highly inhibited, and transmission of pyriproxyfen from the females to the water was revealed. the transfer of the chemical to the water decreased with time before the blood meal. chemical analysis for pyriproxyfen on the exoskeleton of treated females demonstrated the rapid disa ...19947807075
quantitative sampling of immature aedes aegypti in metal drums using sweep net and dipping methods.the behavior of aquatic stages of aedes aegypti was evaluated in 200-liter metal drums to develop improved surveillance. when known numbers of larvae recovered with a rectangular net and with a standard dipper were compared, all stages except 1st instar were most numerous in the top 1/3 of the drum. water temperature was the only significant variable affecting the vertical distribution of 4th-instar larvae; light intensity and ph were nonsignificant factors. rust in the water was also thought to ...19947807082
aedes albopictus distribution, abundance, and colonization in lee county, florida, and its effect on aedes aegypti.in 1992 the known southern limit of aedes albopictus in florida was in lee county. through oviposition surveillance, the distribution of ae. albopictus was determined, and its frequency relative to aedes aegypti and colonization pattern of areas previously occupied by ae. aegypti were examined in lee county. the data collected in the first year of surveillance demonstrate the ability of ae. albopictus to rapidly and preferentially colonize large expanses of rural southwest florida. urban and sub ...19947807083
emergency control of aedes aegypti in the dominican republic using the scorpion 20 ulv forced-air generator.in an effort to develop a more effective measure for use in emergency control of the dengue vector aedes aegypti. applications of a combination of a larvicide (bacillus thuringiensis israelensis [b.t.i.]) and an adulticide (permethrin) were made using a truck-mounted forced-air generator (scorpion 20) and evaluated in the dominican republic. this method has the potential to simultaneously control adults and larvae. in bioassay cages placed in household water containers at the time of application ...19947807084
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