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comparison of the in vivo and in vitro activity of the delta-endotoxin of bacillus thuringiensis var. morrisoni (hd-12) and two of its constituent proteins after cloning and expression in escherichia coli.the insecticidal crystal delta-endotoxin of bacillus thuringiensis var. morrisoni hd-12 contains at least five polypeptides in the range 126-140 kda. immune blotting revealed that individual proteins in this complex share homology with a range of other b. thuringiensis delta-endotoxins. in vivo the native hd-12 crystal killed a lepidopteran larva (pieris brassicae) and a dipteran larva (anopheles gambiae), but not the related dipteran aedes aegypti. in vitro the solubilized activated crystal lys ...19882832170
common features of bacillus thuringiensis toxins specific for diptera and lepidoptera.the complete nucleotide sequence of a cloned gene encoding a 130-kda crystal protein of bacillus thuringiensis (b.t.) subspecies israelensis has been determined. the recombinant protein (bt8) was purified and shown to be a mosquito-specific toxin with a lc50 value of 43 ng/ml to third-instar larvae of aedes aegypti. bt8 is processed by proteases or midgut extracts of mosquito larvae into toxic fragments of 68-78 kda. deletion mapping indicated that the active fragment of bt8 is localized in the ...19882833395
a bacillus thuringiensis subsp. israelensis gene encoding a 125-kilodalton larvicidal polypeptide is associated with inverted repeat sequences.a gene encoding a 125-kilodalton (kda) mosquitocidal delta-endotoxin was cloned from the 72-mda resident plasmid of bacillus thuringiensis subsp. israelensis. this gene is similar in its 3' region to the gene encoding the 135-kda protein previously cloned (c. bourgouin, a. klier, and g. rapoport, mol. gen. genet. 205:390-397, 1986). escherichia coli recombinant clones harboring the 125-kda gene were toxic to larvae of the three mosquito species aedes aegypti, anopheles stephensi, and culex pipie ...19882841292
vector competence of aedes albopictus from houston, texas, for dengue serotypes 1 to 4, yellow fever and ross river viruses.a combination of virus infection and transmission experiments showed that a houston, texas strain of aedes albopictus is a competent vector for dengue (den), yellow fever (yf) and ross river (rr) viruses. however, at 14 days incubation, den virus infection rates in a puerto rican strain of aedes aegypti were significantly higher for each of the four den serotypes, except den-1, than in houston ae. albopictus fed simultaneously on the same virus suspensions. the degree of correlation between diss ...19872849638
induction of salivation in biting midges and mosquitoes, and demonstration of virus in the saliva of infected insects.culicoides biting midges and aedes aegypti (linnaeus) mosquitoes were induced to salivate by the topical application of pilocarpine, neostigmine, malathion and dimethoate; of these, malathion was the most effective. drops of saliva produced by virus-infected midges and mosquitoes were shown to contain virus. the method could be used to demonstrate transmission in insects infected with a variety of pathogens.19872856508
comparative susceptibility of mosquito species and strains to oral and parenteral infection with dengue and japanese encephalitis viruses.thirty-four strains of asian and pacific mosquitoes belonging to 22 species of 7 genera were compared for oral and/or parenteral susceptibility to infection with 1 or more strains of each of the 4 dengue serotypes. surprisingly, several species of common man-biting aedes were much more susceptible to oral infection with each of the 4 dengue serotypes than was aedes aegypti. these species included aedes albopictus and members of the scutellaris group of the subgenus stegomyia found on south pacif ...19852860816
effect of weekly releases of toxorhynchites amboinensis (doleschall) on aedes aegypti (l.) (diptera: culicidae) in new orleans, louisiana. 19852861216
disease-bearing insects brought in by international aircraft into singapore.fifty-seven (17.3%) of 330 incoming aircraft landing at changi international airport were found to harbour mosquitoes and other insects on board. the frequency of insects detected in aircraft from the southeast asian countries varied from 7.1% to 32.2%. live insects were found in 5 (6.1%) of 82 aircraft disinsectized by the "block away" method. the species of mosquitoes brought in were: culex quinquefasciatus (96), culex tritaeniorhynchus (1), aedes albopictus (2) and aedes aegypti (1). none of ...19852862709
arboviruses and lemurs in madagascar: experimental infection of lemur fulvus with yellow fever and west nile viruses.in previous serological surveys of lemurs in madagascar, antibodies against flaviviruses were frequently detected. to examine the epidemiological role of lemur fulvus, experimental infections with yellow fever (yf) virus and west nile (wn) virus were performed. yf and wn infections were clinically unapparent. a 3 to 4-day-long viremia, with moderate levels was observed with yf virus. wn virus, especially the strain isolated in madagascar, provoked a 4 to 6-day-long viremia sufficient to infect a ...19852862804
experimental study of the reproduction of karshi virus (togaviridae, flavivirus) in some species of mosquitoes and ticks.the strain kaz-816 of karshi virus was isolated in 1976 from h. asiaticum ticks collected in the north of central asia (alma-ata region of the kazakh soviet socialist republic). both ticks and mosquitoes can be vectors of karshi virus as proved experimentally by reproduction of the virus in hyalomma asiaticum and dermacentor daghestanicus ticks and culex pipiens molestus, anopheles atroparvus an aedes aegypti mosquitoes as well as by transmission to newborn mice by the bite of infected mosquitoe ...19852864824
variable infectivity of third-stage larvae of brugia malayi.infectivity of third-stage larvae of brugia malayi was assessed following intraperitoneal inoculation into jirds, meriones unguiculatus. larvae were of two ages and were derived from two sites in aedes aegypti mosquitoes, i.e., specimens collected from the thorax 11 days after infection and from the head on day 14. larvae from the thorax had just completed the second moult and measured 990 to 1100 micron in length. only 6% of these specimens developed to adult worms in jirds. larvae that migrate ...19852866213
effects of cyromazin and methoprene on the developmental stages of anopheles dirus, aedes aegypti and culex quinquefasciatus (diptera : culicidae).the effects of two chemical compounds, cyromazin and methoprene, on the developmental stages of anopheles dirus, aedes aegypti and culex quinquefasciatus were investigated under laboratory conditions, with the mean temperature of 24 degrees +/- 1 degree c and the relative humidity at 65-75%. both compounds were tested against the second, third and fourth instar larvae. the concentrations of cyromazin used for an. dirus and cx. quinquefasciatus ranged from 0.0008 to 0.5 mg/l; and for ae. aegypti ...19852866585
variations of four aedes aegypti mosquito strains in their susceptibility to and transmissibility of tahyna virus.aedes aegypti mosquitoes originating from different colonies were infected with tahyna virus by sucking on viraemic newborn mice (peak titre 10(2) x 5 mouse i.c. ld50/0.01 ml). the mosquitoes of laboratory strain "london" proved most susceptible (infection rate 74.2%, transmission rate 60%), while mosquitoes of the laboratory strain "basel" and strain "bangkok" (southeast asia) were less susceptible (infection rate 23.7 and 17.6%, respectively, transmission rate 6.0 and 10.0%, respectively). mos ...19852866696
[abundance of larvae of urban mosquitoes during the campaign of the eradication of aedes aegypti (linnaeus, 1762) and of dengue in cuba (1981-82)]. 19852870540
transovarial transmission of tahyna virus by aedes aegypti mosquitoes (strain bangkok) 19862873736
efficacy of arosurf--a monomolecular surface film, in controlling culex quinquefasciatus say, anopheles stephensi liston & aedes aegypti (l). 19862874113
[effect of delta-endotoxin of bacillus thuringiensis israëlensis on biochemical functional relationships in diptera aedes aegypti].a study of the action of very low doses of the delta-endotoxin of bacillus thuringiensis israëlensis on the larvae of aedes aegypti (diptera) gave evidence for peculiar properties of the dose/effect relations based on the variations of the regression slopes of functional relationships between the pairs cysteine/serine and fatty acids/histidine, by contrast with the pair fatty acids/glucose which exhibited a classical shaped relation. this indicates "crypto-toxicological" processes, not lethal by ...19862876759
the integrated use of toxorhynchites amboinensis and ground-level ulv insecticide application to suppress aedes aegypti (diptera: culicidae). 20102877093
[dengue vector density survey in liuchiu, pintung, taiwan].the first outbreak of dengue in taiwan in 35 years was recorded in the summer of 1981 in liuchiu, pintung, a small offshore island of southern taiwan. an investigation team visited the affected area during the period of 14-17 october 1981 and collected 8,641 mosquito larvae, of which 4,432 were aedes aegypti and 4,182 were ae. albopictus. the house index, container index and breteau index were 44.2, 23.9 and 73.0 for ae. aegypti and 41.3, 17.0 and 51.9 for ae. albopictus, respectively. both spec ...19862880696
laboratory study on the mosquito larvicidal properties of leaf and seed extract of the plant agave americana.experiments on the leaf extract tested against three mosquito species led to 100% mortality of stage 4 anopheles, aedes and culex larvae at a concentration of 0.08% within 24-48 h, whereas 100% mortality of stage 1 larvae occurred at lower concentrations: 0.0032% for aedes aegypti, 0.016% for culex quinquefasciatus and 0.08% for anopheles stephensi, and was more rapid. at the end of 24 h, the highest dilution of the seed extract studied (1:200) produces a larval mortality of 100% for anopheles a ...19872882030
efficacy of czechoslovak and soviet bacillus thuringiensis (serotype h-14) formulations against mosquito larvae.laboratory and field comparisons were made with two wettable powder formulations of bacillus thuringiensis serotype h-14 (b. t. h-14) prepared in czechoslovakia ("moskitur") and the ussr ("baktokulicid"). expressed in the international aedes aegypti toxic units (tu x mg-1) the potency of these two test formulations was greater than that of the institute pasteur standard ips-78 (= 1,000 tu x mg-1), i.e. moskitur had a potency of about 1,500 tu x mg-1 and the soviet baktokulicid 2,000 tu x mg-1. t ...19872883232
immunoelectron microscopic demonstration of pancreatic polypeptide in midgut epithelium of hematophagous dipterans.midguts of mosquitoes, aedes aegypti and anopheles stephensi, and of the tsetse fly, glossina morsitans morsitans, as well as guinea pig pancreas, were prepared for electron microscopy by using low-temperature embedding in lowicryl k4m. rabbit antiserum to bovine pancreatic polypeptide (pp) crossreacted with secretory granules of pancreatic pp-producing cells and of the clear cells in mosquito gut. rabbit antiserum to human somatostatin crossreacted with the control tissue, guinea pig pancreas d ...19872885369
proteolysis in the gut of mosquito larvae results in further activation of the bacillus sphaericus toxin.gut proteases from the larvae of the mosquito culex pipiens convert the 43-kilodalton (kda) toxin from bacillus sphaericus 2362 to a 40-kda peptide. the 50% lethal concentration of this peptide for tissue culture-grown cells of culex quinquefasciatus was 1.0 microgram/ml (as determined by the intracellular atp assay), 54-fold less than that of the 43-kda peptide. gut proteases from anopheles gambiae and aedes aegypti, as well as bovine pancreatic trypsin, also converted the 43-kda protein to a 4 ...19872886104
cloning and expression of 130-kd mosquito-larvicidal delta-endotoxin gene of bacillus thuringiensis var. israelensis in escherichia coli.five recombinant e. coli clones exhibiting toxicity to aedes aegypti larvae were obtained from a library of 800 clones containing xbai dna fragments of 110 kb plasmid from b. thuringiensis var. israelensis. all the five clones (pmu 14/258/303/388/679) had the same 3.8-kb insert and encoded a major protein of 130 kda which was highly toxic to a. aegypti larvae. three clones (pmu 258/303/388) transcribed the 130 kd a gene in the same direction as that of lac z promoter of puc12 vector whereas the ...19872890080
use of enzyme immunoassay and nucleic acid hybridization for detecting sindbis virus in infected mosquitoes.aedes aegypti mosquitoes were inoculated intrathoracically with prototype sindbis virus, held at 26.7 degrees c for from 0-95 h and placed at -70 degrees c. individual mosquitoes were tested for virus by plaque assay in vero cells, for viral rna by nucleic acid hybridization using a cloned cdna probe, and for viral protein by enzyme-linked immunosorbent assay. virus was detected by plaque assay as early as 8 h after infection. sindbis virus rna was detected by nucleic acid hybridization 18 h aft ...19872890652
the effectiveness of mosquito coils containing esbiothrin under laboratory and field conditions.tests were made to correlate the chemical content of mosquito coils with the knockdown and bite-inhibitory action of the smoke in the laboratory and with the protective effect in field use. smoke from a blank coil, containing no pyrethroid, gave no knockdown, 10% inhibition of biting in the laboratory using aedes aegypti, and 39% protection in field tests in village huts on the kenyan coast with a mixed population of mosquitoes including 71% anopheles gambiae. coils containing low experimental c ...19872891344
effects of azadirachtin on insect cytochrome p-450 dependent ecdysone 20-monooxygenase activity.the effects of the insect growth and ecdysis inhibitor azadirachtin on ecdysone 20-monooxygenase activity were examined in three insect species. homogenates of wandering stage third instar larvae of drosophila melanogaster, or abdomens from adult female aedes aegypti, or fat body or midgut from last instar larvae of manduca sexta were incubated with radiolabelled ecdysone and increasing concentrations of azadirachtin and the ecdysone 20-monoxygenase activity quantified by radioassay. azadirachti ...19882900005
[monitoring of mosquito vectors at international airports of the south pacific region].a survey conducted in eight airports of the south pacific, yielded 2,044 larvae and 136 adult forms, belonging to 25 culicidae species. breeding places were found in every airport, either within the perimeter (6 airports) or in the protective zone. some potentially dangerous vectors were identified: aedes aegypti (4 airports), ae. polynesiensis, ae. vigilax, anopheles farauti (2 airports), culex annulirostris, c. p. quinquefasciatus. vector control measures should be strengthened to suppress eve ...19882900080
[arboviroses in the region of nosy-bé, madagascar. serologic and entomologic data].since 1977, the pasteur institute of madagascar has been studying, during six surveys, the arboviruses of nosy-be area, in the north-west of madagascar. 47.2% out of 271 human sera and 11.3% out of 151 sera of lemurs, tested for antibodies to 16 arboviruses by the haemagglutination inhibition test, are positive. the results show an important prevalence of flaviviruses. west nile and dengue 1 viruses were probably circulating some years before the surveys. antibodies against sindbis and rift vall ...19882900082
biological characterization of plaque-size variants of yellow fever virus in mosquitoes and mice.we isolated plaque-size variants of a south american strain of yellow fever virus, and compared their ability to infect orally and be transmitted by vector aedes aegypti mosquitoes with that of the uncloned, parental virus. we analyzed the same clonal isolates in mouse virulence experiments. no significant differences could be demonstrated in the capacities of the variants to infect and be transmitted by mosquitoes or in mouse virulence tests. the 17d vaccine virus (derived from the african asib ...19882902770
factors affecting oviposition site preference by toxorhynchites splendens in the laboratory.in a series of laboratory oviposition assays, gravid toxorhynchites splendens exhibited a preference for cups containing aedes aegypti larval rearing water, but not for cups containing liquid cultures of bacteria, live ae. aegypti in distilled water, ae. aegypti larval holding water with reduced bacterial contamination, or methyl propionate at 0.1, 0.2 and 0.3% in distilled water. preoviposition flight behavior was elicited by dark-colored containers, but few eggs were deposited if they containe ...19882903901
polycyclic aromatic compounds as phototoxic mosquito larvicides.the phototoxicity of 2-acetylnaphthalene, 1-acetylnaphthalene, 1-naphthalenecarboxaldehyde, 9-xanthenone, 9-thioxanthenone, 9-methylanthracene, anthracene, alpha-terthienyl, pyrene and fluoranthene was tested with larvae of aedes aegypti, ae. taeniorhynchus and culex quinquefasciatus. the larvae were exposed to the chemicals in the presence of sunlight for intervals from 1 to 6 hr and the corresponding lc50 values calculated. the lc50 values determined when the 6-hr exposure was followed by 18 h ...20092904948
studies on bioassay of the entomopathogenic hyphomycete fungus tolypocladium cylindrosporum in mosquitoes.larvae of aedes aegypti, ae. vexans and culiseta inornata were used to study the pathogenicity of the hyphomycete fungus tolypocladium cylindrosporum. experiments consisted of continuous exposure of second-instar larvae to 5 concentrations of conidia at 10, 15, 20 and 25 degrees c. the 3 test species were susceptible at all temperatures tested. there was generally a direct relationship between dosage and pathogenicity in the host population, however linear relationships between probit mortality ...19872904966
[effect of temperature on the infectivity of the iridovirus and densonucleosis virus of blood-sucking mosquitoes].mosquito densonucleosis virus and iridovirus were used to study the influence of temperature on their infectivity. biological assays of mosquito densonucleosis virus were carried out in larvae of i-ii instar of aedes aegypti mosquitoes, those of mosquito iridovirus in larvae of galleria mellonella. the rate of inactivation was found to be directly dependent on the dose of the heat treatment. treatment at 60 degrees c led to complete loss of iridovirus infectivity; the virus activity declined con ...20102905849
toxicity, localization and elimination of the phototoxin, alpha-terthienyl, in mosquito larvae.mosquito larvae were examined to determine interspecific and interstrain differences in susceptibility to the larvicidal effects of the plant-derived phototoxin, alpha-terthienyl (alpha-t). the lc50 values were as follows: aedes aegypti, 4 ppb; ae. epactius, 6 ppb; anopheles stephensi, 14 ppb; malathion-susceptible culex tarsalis (s), 12 ppb; malathion-resistant cx. tarsalis (r), 16 ppb. fluorescence studies indicated localization of alpha-t in the midgut epithelium and in the lumen of malpighia ...19882906359
specificity of action on mosquito larvae of bacillus thuringiensis israelensis toxins encoded by two different genes.a 135 kda protein gene and two open reading frames (orf1 and orf2) have been cloned from a large plasmid of bacillus thuringiensis israelensis (bourgouin et al. 1986). the escherichia coli recombinant clones containing these genes were highly toxic to larvae of aedes aegypti, anopheles stephensi and culex pipiens. from subcloning experiments it was deduced that the 135 kda polypeptide alone was responsible for the toxic activity on both a. aegypti and an. stephensi larvae. in contrast, the prese ...19882906402
use of an artificial bromeliad to show the importance of color value in restricting colonization of bromeliads by aedes aegypti and culex quinquefasciatus.an artificial bromeliad was developed which, painted and containing an infusion water, elicited ovipositional response by caged adult aedes aegypti, culex quinquefasciatus, wyeomyia vanduzeei and wy. mitchellii. comparison was made of the ovipositional response of adults of the four mosquito species to artificial bromeliads painted black, white, dark green and deep blue. adult ae, aegypti and wy. vanduzeei did not discriminate significantly between white, dark green and deep blue, but whereas ae ...19852906654
mathematical models of the effectiveness and persistence of mosquito repellents.two models of the effectiveness and persistence of mosquito repellents on the skin were developed from published functions and data. the probit plane model, y = a + b1x1 + b2x2, relates the response (y, in probits) of the mosquito test population to the log dose (x1) of repellent applied and the test period, or elapsed time from the time of application (x2). the exponential decay model, z = x1 + (b2/b1)x2, estimates the repellent residue (log-1 z) from x1 and x2. the models were validated with o ...19852906657
tests of ultrasonic emissions on mosquito attraction to hosts in a flight chamber.five ultrasonic devices generating fundamental frequencies of 20-70 khz were tested for their efficacy in repelling mosquitoes. four species (anopheles quadrimaculatus, aedes aegypti, ae. triseriatus and haemagogus equinus), were used in a flight chamber in which females must fly upwind against the direction of the sound waves and around the ultrasonic devices to reach a trap downwind of a source of human breath and skin emanations. repellency was rated by the number of mosquitoes entering the t ...19852906666
the effect of tolypin in tolypocladium niveum crude extract against mosquito and blackfly larvae in the laboratory.the efficacy of tolypin against mosquito and blackfly larvae was studied under laboratory conditions. it was tested against culex molestus, aedes aegypti, anopheles maculipennis, simulium noelleri and odagmia ornata. a concentration 0.1 mg/ml caused 100% mortality in all species tested and a concentration 0.001 mg/ml caused 100% mortality only in the two species of blackflies used within 24 hours.19882906895
evaluation of two new insect growth regulators against mosquitoes in the laboratory.biological activity of two new igrs was studied under laboratory conditions against 2nd- and 4th-instar larvae and pupae of anopheles quadrimaculatus, aedes aegypti and culex tarsalis. the igr s-21149, an oxime [0-(2-(4'-phenoxyphenoxy)ethyl propionaldoxime], produced an overall mortality or inhibition of emergence of 95% (when 4th instar treated) at 0.0047, 0.0013 and 0.00041 mg/liter in the three species, respectively. the ei95 values for the second igr s-31183, a pyridine compound, [1-(4'-phe ...19862906962
determination and significance of suspended protein in wastewater.a simple method is presented to measure the nutrient load of wastewater. suspended particles, including microorganisms, are collected on a membrane filter by vacuum filtration, followed by colorimetric protein assay. soluble proteins can be determined in the filtrate by precipitation. in domestic sewage and agricultural dairy wastewater, the largest portion of protein was retained on the membrane. young larvae of culex nigripalpus, cx. quinquefasciatus and aedes aegypti pupated when maintained i ...19862906966
differences between the nutritional reserves of laboratory-maintained and field-collected adult mosquitoes.individual female mosquitoes from field populations of aedes aegypti, culex nigripalpus and coquillettidia perturbans were analyzed for sugar, glycogen and lipids. controls were maintained in the laboratory for 7 to 10 days on 2% and either 10 or 20% sucrose. mosquitoes held in the laboratory had significantly more glycogen and lipid than field-collected mosquitoes of the same species. laboratory mosquitoes maintained on 10 or 20% sucrose contained more sugar than did field mosquitoes. mosquitoe ...19862906967
growth of three mosquitoes on two larval diets measured by protein accumulation.larval growth recorded as accumulation of protein was measured in aedes aegypti, culex nigripalpus and culex quinquefasciatus, raised on liver powder or dry brewer's yeast. in the early stages all 3 species grew faster on liver powder, but at pupation there was no significant difference in protein content between diets and among species. aedes aegypti pupated one day ahead of culex.19862906975
comparative studies of metarhizium anisopliae and tolypocladium cylindrosporum as pathogens of mosquito larvae.mosquito fungal pathogens, metarhizium anisopliae and tolypocladium cylindrosporum, were compared with regard to virulence against the larvae of aedes aegypti, anopheles stephensi and culex pipiens. culex pipiens larvae were much more susceptible to m. anisopliae conidia than an. stephensi or ae. aegypti. but ae. aegypti and cx. pipiens larvae were equally susceptible to t. cylindrosporum propagules which weakly attack an. stephensi. using a high concentration conidial suspension (10(7) sp/ml) o ...19862906985
detection of yellow fever virus nucleic acid in infected mosquitoes by rna:rna in situ hybridization.an in situ hybridization technique was developed for the strand-specific detection of yellow fever virus (yfv) rna. an 35s-labeled, transcribed rna probe was used to detect positive-sense polarity yfv genomic rna in infected c6/36 (aedes albopictus) cells, dissected mosquito tissues, and sections of plastic-embedded, yfv-infected aedes aegypti mosquitoes. mosquito tissues fixed in buffered formalin retained morphological integrity. the low concentrations of probe used yielded high specific signa ...19882907776
the functional response of toxorhynchites rutilus rutilus to changes in the population density of its prey aedes aegypti.we present an analysis of the functional response of the predator toxorhynchites rutilus rutilus (coquillett) to changes in the density of the larvae of aedes aegypti (l.) (diptera: culicidae). the experiment was replicated for five different ages, and at three different densities of the predator. the data were fitted to rogers' (1972) random predator equation by non-linear least-squares in order to estimate searching efficiency and handling time for each experimental treatment. the data show th ...19882908786
two highly related insecticidal crystal proteins of bacillus thuringiensis subsp. kurstaki possess different host range specificities.two genes encoding insecticidal crystal proteins from bacillus thuringiensis subsp. kurstaki hd-1 were cloned and sequenced. both genes, designated cryb1 and cryb2, encode polypeptides of 633 amino acids having a molecular mass of ca. 71 kilodaltons (kda). despite the fact that these two proteins display 87% identity in amino acid sequence, they exhibit different toxin specificities. the cryb1 gene product is toxic to both dipteran (aedes aegypti) and lepidopteran (manduca sexta) larvae, whereas ...19892914879
ingestion, dissolution, and proteolysis of the bacillus sphaericus toxin by mosquito larvae.larvae of culex quinquefasciatus are much more susceptible to the toxin of bacillus sphaericus than are larvae of aedes aegypti. in the present study, the rate of ingestion, dissolution, and the cleavage by midgut proteases of the b. sphaericus toxin were compared in larvae of these species to determine whether these factors account for the differences in susceptibility. during filter feeding, larvae of both species removed significant quantities of b. sphaericus toxin from suspensions. filtrati ...19892915145
hemocyte population changes during the immune response of aedes aegypti to inoculated microfilariae of dirofilaria immitis.ultrastructural and lectin-binding studies have established that the melanotic encapsulation reaction of aedes aegypti liverpool strain against inoculated dirofilaria immitis microfilariae (mff) is a hemocyte-mediated reaction. total hemocyte counts from mff-inoculated (= immune-activated), saline-inoculated, and uninoculated female a. aegypti were determined using a hemocoel perfusion technique. total hemocyte populations in uninoculated mosquitoes were significantly larger in younger mosquitoe ...19892918431
effects of the chitin synthetase inhibitor plumbagin and its 2-demethyl derivative juglone on insect ecdysone 20-monooxygenase activity.the chitin synthetase inhibitor plumbagin and its 2-demethyl derivative juglone were found to inhibit in a dose-response fashion the cytochrome p-450 dependent ecdysone 20-monooxygenase activity associated with adult female aedes aegypti, wandering stage larvae of drosophila melanogaster, and fat body and midgut from last instar larvae of manduca sexta. the concentration of these naphthoquinones required to elicit a 50% inhibition of the steroid hydroxylase activity in all the insects was approx ...19882973991
evaluation of some adhesives for collecting musca domestica and chrysomya megacephala adults or mosquito larvae in sticky traps.1. seven types of water-insoluble adhesives were evaluated in sticky traps for collecting adults of musca domestica l. and chrysomya megacephala (fabricius) or mosquito larvae (aedes aegypti (l.) and culex quinquefasciatus say). 2. adhesive viscosity affected the tackiness of the glues and this determined their trapping efficiency in air or water. 3. from the 'hyvis' range of adhesives tested, 'hyvis 200' was most effective for trapping adult flies. 4. with 24 h exposure to fourth instar ae.aegy ...19872979541
anti-mosquito antibodies decrease the reproductive capacity of aedes aegypti.aedes aegypti (l.) fed on rabbits immunized with mosquito antigens showed a reduction in fecundity in the first oviposition and decreased viability of the progeny. feeding behaviour of mosquitoes was not affected and no significant mortality was observed due to the presence of anti-mosquito antibodies in the bloodmeal. antibodies were detected in the oocytes of mosquitoes 48 h after the bloodmeal. the role of specific antibodies in influencing fecundity is discussed.19882980164
landing periodicity of the mosquito aedes aegypti in trinidad in relation to the timing of insecticidal space-spraying.diel landing periodicity (biting cycle) of domestic aedes aegypti (l.) in trinidad, west indies, was monitored using human bait during january-august 1980. the periodicity of females was predominantly diurnal (95.2% arriving during daylight or twilight) and bimodal, with consistent peaks at 06.00-07.00 and 17.00-18.00 hours. the diel periodicities at indoor and outdoor sites were virtually identical. larger numbers of adults were collected outside than inside houses. it is recommended that the t ...19882980173
effects of 'closed' houses on the aedes aegypti eradication programme in trinidad.the effects of closed (i.e. locked) houses on the efficiency of control measures against aedes aegypti (l.) were monitored weekly for 1 year (march 1981 to february 1982) using ovitraps in the towns of felicity and trincity, trinidad. regular anti-aegypti activities comprised source reduction, focal treatment with larvicidal 1% temephos sand granules and perifocal treatment with 40% wp fenthion. in felicity, only 6% of houses were closed and after each treatment cycle ovitrap indices showed 100% ...19882980174
ovitrap surveys of dengue vector mosquitoes in chiang mai, northern thailand: seasonal shifts in relative abundance of aedes albopictus and ae. aegypti.aedes aegypti (l.) and aedes albopictus (skuse) were surveyed using ovitraps in residential areas in chiang mai, northern thailand. egg populations (both species inclusive) remained low in the dry season, but increased/decreased exponentially during the first/latter half of the rainy season, respectively. this seasonal pattern was similar to the seasonal distribution of dengue haemorrhagic fever cases in the area. during the dry season (november-march) ae.aegypti was dominant in urban and indoor ...19882980189
anti-mosquito antibodies and their effects on feeding, fecundity and mortality of aedes aegypti.anti-mosquito antibodies, produced in mice inoculated with mosquito homogenates or exposed to mosquito bites, reacted with a variety of mosquito antigens including muscle, gut, fat body and nervous tissue; those in anti-mosquito bite sera reacted solely with salivary glands. mosquitoes fed on restrained immunized mice showed a significant increase in mortality correlated to both the titre and specificity of the anti-mosquito antibodies ingested. no changes in their fecundity or feeding success w ...19882980191
detection and localization of antibody ingested with a mosquito bloodmeal.mouse immunoglobulins were found to persist in aedes aegypti (l.) mosquito bloodmeals for 2-3 days after ingestion. immunoenzyme labelling revealed mouse antibody specifically bound to the mosquito midgut epithelium after ingestion; immunogold labelling of thin sections revealed mouse antibody within the cytoplasm of the microvilli on the midgut epithelium. ingested mouse antibody was not conclusively demonstrated bound to tissues outside the gut, though antibody was detected in mosquito haemoly ...19882980192
molecular cloning of the delta-endotoxin gene of bacillus thuringiensis var. israelensis.a transformant of bacillus megaterium, vb131, was isolated which carries a 6.3-kb xbai segment of the crystal toxin gene of bacillus thuringiensis var. israelensis (bti) cloned in a vector plasmid pbc16 to yield pvb131. the chimeric plasmid dna from vb131 was introduced into a transformable bacillus subtilis strain by competence transformation. both the b. megaterium vb131 strain and the b. subtilis strain harboring the chimeric plasmid produced irregular, parasporal, phase-refractile, crystalli ...19852987085
baculovirus-mediated expression of bacterial genes in dipteran and mammalian cells.a recombinant baculovirus containing the escherichia coli chloramphenicol acetyltransferase (cat) gene under the control of the rous sarcoma virus long terminal repeat promoter and the e. coli beta-galactosidase gene under the control of the very late baculoviral polyhedrin promoter was used to determine if autographa californica nuclear polyhedrosis virus, a baculovirus of lepidoptera, can enter and express viral dna in dipteran (drosophila sp.) and mammalian (mus sp.) cells that are considered ...19852993646
micro-lipid-droplet encapsulation of bacillus thuringiensis subsp. israelensis delta-endotoxin for control of mosquito larvae.the crystal delta-endotoxin of bacillus thuringiensis subsp. israelensis is less toxic to larvae of anopheles freeborni than to larvae of aedes aegypti. however, when solubilized crystal was used, larvae from both species showed similar sensitivities. this effect presumably was due to the differences in feeding behavior between the two mosquito larvae when crystal preparations are used. a procedure is described whereby both crystal and solubilized b. thuringiensis subsp. israelensis toxin were e ...19853002272
specificity of bacillus thuringiensis var. colmeri insecticidal delta-endotoxin is determined by differential proteolytic processing of the protoxin by larval gut proteases.the native crystal delta-endotoxin produced by bacillus thuringiensis var. colmeri, serotype 21, is toxic to both lepidopteran (pieris brassicae) and dipteran (aedes aegypti) larvae. solubilization of the crystal delta-endotoxin in alkaline reducing conditions and activation with trypsin and gut extracts from susceptible insects yielded a preparation whose toxicity could be assayed in vitro against a range of insect cell lines. after activation with aedes aegypti gut extract the preparation was ...19863009187
susceptibility of indonesia colonies of aedes aegypti and aedes albopictus mosquitoes to experimental infection with chikungunya virus. 19863023740
bacillus thuringiensis var. israelensis delta-endotoxin. cloning and expression of the toxin in sporogenic and asporogenic strains of bacillus subtilis.a plasmid-borne gene from bacillus thuringiensis var. israelensis encoding a 27,340 mr insecticidal delta-endotoxin has been cloned on a bifunctional multicopy plasmid in a wild-type sporogenic strain and two asporogenic mutants of bacillus subtilis. the delta-endotoxin gene is expressed at a low level during vegetative growth in all three strains, but the synthesis of the toxin increases markedly during the third hour of stationary phase for both the sporogenic strain and an asporogenic mutant ...19863025453
structurally related bacillus thuringiensis delta-endotoxins display major differences in insecticidal activity in vivo and in vitro.many strains within the 22 serotypes of bacillus thuringiensis produce crystal delta-endotoxins with slight differences in their insecticidal toxicity spectrum in vivo. since the basis of this specificity is unknown, we chose to compare the activity of delta-endotoxins from three strains: b. thuringiensis var. kurstaki hd-1, var. aizawai hd-249 and var. thuringiensis hd-350, both in vivo and on insect cell lines in vitro. immunoblotting with antisera to activated var. kurstaki p1 lepidopteran to ...19863027111
[biochemical manifestations of the poisoning of larvae of aedes aegypti (insecta, diptera) by the delta-endotoxin of bacillus thuringiensis israelensis. i. hemolymph carbohydrates].the glycemia of 4th instar larvae of aedes aegypti (diptera culicidae) was determined over a 30 min to 36 hrs period following their immersion in water containing 0.00-0.01-0.02-0.1-1.0 mg per liter of a 12,000 i. u. per mg preparation of the delta-endotoxin of bacillus thuringiensis israelensis. seven major carbohydrate fractions were separated in the haemolymph, among which glycogen, trehalose and glucose were identified; the most concentrated of the 4 remaining unknown fractions, exhibits a s ...19863030517
characterization of the genes encoding the haemolytic toxin and the mosquitocidal delta-endotoxin of bacillus thuringiensis israelensis.the crystalline parasporal inclusions (crystals) of bacillus thuringiensis israelensis (bti), which are specifically toxic to mosquito and black fly larvae, contain three main polypeptides of 28 kda, 68 kda and 130 kda. the genes encoding the 28 kda protein and the 130 kda protein have been cloned from a large plasmid of bti. escherichia-coli recombinant clones containing the 130 kda protein gene were highly active against larvae of aedes aegypti and culex pipiens, while b. subtilis recombinant ...19863031426
[aedes aegypti (l.): importance of its bioecology in the transmission of dengue and other arboviruses. ii. bibliography]. 19883042176
[aedes aegypti (l.): importance of its bioecology in the transmission of dengue and other arboviruses. i].the bioecological parameters which are of special importance in the epidemiology of dengue, yellow fever, and other arboviruses are discussed. three levels are retained: the nature of aedes aegypti-man contacts, the susceptibility of the mosquito to the pathogen and multiplication of the latter, and the transmission. the trophic preferences, the density variations, the daily survival rate, the egg diapause, and man influences are the main vector-dependent ecological factors. temperature and gene ...19883042180
[predatory capacity of poecilia (lebistes) reticulata peters, 1895 (cyprinodontiformes: poecillidae) against larvae of culex quinquefasciatus say, 1823 and aedes aegypti linnaeus, 1762 (diptera: culicidae) under laboratory conditions in cuba]. 20093045915
uptake and development of wuchereria bancrofti in aedes aegypti and haitian culex quinquefasciatus that were fed on a monkey with low-density microfilaremia.colonized mosquitoes of culex quinquefasciatus (haitian strain) and aedes aegypti (liverpool strain) were blood fed on a patas monkey (erythrocebus patas) that had been experimentally infected with the haitian strain of wuchereria bancrofti and harbored a consistently low microfilaremia (1-3 mf per 20 mm3). both species ingested more than twice the expected number of microfilariae (mf), i.e. 1.9 and 0.77 mf per mosquito, respectively. however, at 10-16 hours post ingestion only 4.2% of the mf ha ...19883057592
the biology of aedes albopictus.the biology of aedes albopictus is reviewed, with emphasis on studies of ecology and behavior. the following topics are discussed: distribution and taxonomy, genetics, medical importance, habitat, egg biology, larval biology, adult biology, competitive interactions, comparative studies with aedes aegypti, population dynamics, photoperiodism, and surveillance and control.19883068349
effect of nosema algerae vavra and undeen spores infection on longevity and fecundity of larval instars of aedes aegypti l. and culex fatigans weid. 19863108151
mechanical transmission of bacillus anthracis by stable flies (stomoxys calcitrans) and mosquitoes (aedes aegypti and aedes taeniorhynchus).we evaluated the potential of stable flies, stomoxys calcitrans, and two species of mosquitoes, aedes aegypti and aedes taeniorhynchus, to transmit bacillus anthracis vollum 1b mechanically. after probing on hartley guinea pigs with a bacteremia of ca. 10(8.6) cfu of b. anthracis per ml of blood, individual or pools of two to four stable flies or mosquitoes were allowed to continue feeding on either uninfected guinea pigs or a/j mice. all three insect species transmitted lethal anthrax infection ...19873112013
complement effects of the infectivity of plasmodium gallinaceum to aedes aegypti mosquitoes. ii. changes in sensitivity to complement-like factors during zygote development.during transformation into ookinetes, the zygotes of plasmodium gallinaceum are initially resistant to lysis by heat-labile and edta-sensitive factors in the serum of their natural host, the chicken. between 6 and 8 hr postgametogenesis, zygotes cultured in vitro lose their resistance to these factors. loss of resistance to these factors in vitro is reflected by loss of infectivity of the zygotes to aedes aegypti mosquitoes in the presence of native chicken serum. these factors are probably comp ...19873116195
[effect of the viral preparation viroden on aedes aegypti l. mosquitoes in an experiment]. 20093173248
[determination of the efficacy of repellent preparations in relation to the feeding behavior of aedes aegypti and aedes togoi mosquitoes]. 20093173249
exsheathment of microfilariae of brugia pahangi in the susceptible and refractory strains of aedes aegypti.exsheathment of microfilariae of brugia pahangi was studied in susceptible (liverpool) and refractory (bora-bora) strains of aedes aegypti. it was found that the microfilariae tend to carry their sheaths into the haemocoel of both strains of ae. aegypti within two hours after the engorgement of mosquitoes from a rat parasitized by filariae. the percentage of sheathed microfilariae in the haemocoel then progressively decreased to 0% at eight hours and to 1% at 24 hours post-ingestion in the bora- ...19883178339
toxicity of bacillus sphaericus crystal toxin to adult mosquitoes.adult culex quinquefasciatus mosquitoes were killed by alkaline-solubilized bacillus sphaericus toxin when it was introduced by enema into the midgut of the insect but not when it was administered orally. adult aedes aegypti mosquitoes were not affected by the toxin.19883190228
host range and selected factors influencing the mosquito larvicidal activity of the pg-14 isolate of bacillus thuringiensis var. morrisoni.laboratory bioassay of the pg-14 isolate of bacillus thuringiensis var. morrisoni (serotype 8a:8b) against early fourth instar larvae of 8 species of mosquitoes revealed a range of susceptibilities similar to the susceptibilities of these species to bacillus thuringiensis var. israelensis (serotype 14). the most susceptible species were: culex quinquefasciatus, cx. salinarius, anopheles albimanus and aedes aegypti. the least susceptible species tested was an. quadrimaculatus. separate bioassays ...19883193097
effects of larval nutrition on the host-seeking behavior of adult aedes aegypti mosquitoes.adult female aedes aegypti that were reared on a suboptimal diet as larvae were less likely to engage in host-seeking behavior than were adults derived from larvae reared on an optimal diet. a postemergence carbohydrate diet of either 1 or 10% sucrose solution did not affect this response. when the progeny of field-collected aedes vexans were reared in the laboratory, the adults were significantly larger than their parents. this indicated that the larvae of the field population were not as adequ ...19883193101
method for determining settling rates of bacillus thuringiensis serotype h-14 formulations.a water-column apparatus is described in which settling rates of bacillus thuringiensis serotype h-14 [b.t. (h-14)] formulations can be indirectly quantified using mortality of mosquito larvae at restricted depths as an index of b.t. (h-14) activity. to illustrate the type of data provided by this method, commercial b.t. (h-14) products (bactimos, teknar, vectobac) and experimental formulations were compared at the manufacturers' recommended rates for mosquito control. all evaluations utilized l ...19883193109
evaluating ultra-low volume ground applications of malathion against aedes aegypti using landing counts in puerto rico, 1980-84.landing counts made in a residential area in san juan, puerto rico during the 5-year period, 1980-84 indicated that malathion ulv applied by leco fog generators was not effective against aedes aegypti. of 25 applications only 6 resulted in a decrease on the first day after treatment and only one remained much less than the pretreatment count on the second and third days after treatment. daily, the number of mosquitoes landing for a 5-minute period at each of 2 stations was recorded. an ideal yea ...19883193113
feeding behavior of aedes aegypti larvae and toxicity of dispersed and of naturally encapsulated bacillus thuringiensis var. israelensis. 19883198932
efficacy of two formulations of bacillus thuringiensis var. israelensis (h-14) against aedes vexans and safety to non-target macroinvertebrates.an experimental sandoz formulation of bacillus thuringiensis var. israelensis (san 402 sc 98) was several times more effective than abbott abg 6188 against larvae of aedes aegypti and ae. vexans in the laboratory. field applications of san 402 sc 98 at 0.25 liter/ha and abg 6188 at 1.00 liter/ha resulted in more than 97% control of ae. vexans larvae after 48 hours, with residual activity of 24 hours or less. the amphipod, hyallela azteca, and 4 species of water beetles were apparently unaffected ...19883199115
mosquito repellents: monocarboxylic esters of aliphatic diols.selected monocarboxylic esters of aliphatic diols that contained an alicyclic group in the acyl portion of the molecule were effective repellents for aedes aegypti, anopheles quadrimaculatus and an. albimanus when tested on cloth. although 25 of the esters provided greater than 21 days of protection against all 3 species, the repellent potency of the 143 hydroxyesters that were tested was found to vary with mosquito species. anopheles quadrimaculatus was especially susceptible to this type of st ...19883199120
the collection of aedes aegypti and ae. albopictus from baltimore, maryland. 19883199132
phototaxis in aquatic invertebrates: possible use in ecotoxicity tests.a series of experiments has been carried out aimed at (i) a deeper study of the phototaxis of some aquatic invertebrates and (ii) its possible use in ecotoxicity tests. for the first point the phototaxis of the nauplii of artemia salina was examined: through tests carried out under different conditions, it was observed that a marked complex response to light existed, which led to a subdivision between individuals with different phototactic response, mainly depending on the density of the nauplii ...19883229377
phenotypic variability and heterozygosity at an esterase locus in the mosquito aedes aegypti.populations of the yellow fever mosquito, aedes aegypti l. are polymorphic for esterase alleles. this could be because the alleles are neutral or because selection protects the polymorphism, as had been concluded from a study of allele frequencies. a test has been carried out to look for possible associations of esterase heterozygosity with speed of development, body size and spine number symmetry in two spine rows. heterozygotes were found to be larger and slower growing than homozygotes, but t ...19883230031
[susceptibility of aedes aegypti l. mosquitoes infected with an entomopathogenic virus to malarial plasmodia]. 19883231163
[arbovirus infections on the island of nosy-be; serologic and entomologic findings].since 1977, the pasteur institute of madagascar has been studying, during six surveys, the arboviruses of nosy-be area, in the north-west of madagascar. 47.2 p. 100 out of 271 human sera and 11.3 p. 100 out of 150 animal sera (mostly from lemurs), tested for antibodies to 16 arboviruses by the haemagglutination inhibition test, are positive. the results show an important prevalence of flaviviruses. west-nile and dengue 1 viruses were probably circulating some years before the surveys. antibodies ...19883242421
[toxic effects of bacillus thuringiensis var. kurstaki to the immature stage of aedes aegypti]. 19883244164
comparative toxicity of bacillus thuringiensis var. israelensis crystal proteins in vivo and in vitro.bacillus thuringiensis var. israelensis crystal proteins were purified by fplc on a mono q column to yield 130, 65, 28, 53, 30-35 and 25 kda proteins. all the purified proteins killed aedes aegypti larvae after citrate precipitation, but the 65 kda protein was the most toxic. a precipitated mixture of 27 and 130 kda proteins was almost as toxic as solubilized crystals. in assays against a range of insect cell lines, the activated form (25 kda) of the 27 kda protein was generally cytotoxic with t ...19883254944
the stegomyia survey and susceptibility status of aedes aegypti to insecticides in calcutta seaport area. 19883256570
pathogenesis of dengue: challenges to molecular biology.dengue viruses occur as four antigenically related but distinct serotypes transmitted to humans by aedes aegypti mosquitoes. these viruses generally cause a benign syndrome, dengue fever, in the american and african tropics, and a severe syndrome, dengue hemorrhagic fever/dengue shock syndrome (dhf/dss), in southeast asian children. this severe syndrome, which recently has also been identified in children infected with the virus in puerto rico, is characterized by increased vascular permeability ...19883277268
monoclonal antibodies as probes for processing of the mosquito yolk protein; a high-resolution immunolocalization of secretory and accumulative pathways.a library of monoclonal antibodies (mab) directed against yolk polypeptides of the mosquito aedes aegypti was utilized to visualize the secretory pathway of these polypeptides in the fat body and their accumulative pathway in developing oocytes. single and double immunolabelling using mabs and colloidal gold of different sizes confirmed biochemical observation that 200 +/- 5 and 65 +/- 3 kda polypeptides represent subunits of the yolk protein. this immunocytochemical analysis showed that, in tro ...19873307021
dengue and dengue hemorrhagic fever in the americas.there has been a constant increase in the incidence of dengue in the americas over the past 15 years. this has been caused by increased frequency of epidemic activity in most countries, as a result of increased numbers of virus serotypes circulating in the region. the change in disease ecology has resulted in the emergence of dengue hemorrhagic fever/dengue shock syndrome (dhf/dss) in the region, first with a major epidemic in cuba, followed by increased occurrence of sporadic cases of dhf/dss i ...19873313490
dengue in puerto rico: clinical manifestations and management from 1960's to 1987.dengue is a viral disease transmitted by the aedes aegypti mosquito. it is endemic in puerto rico and the caribbean with periodic epidemics occurring at varying intervals. there are three dengue serotypes present in puerto rico, at the present time. the clinical manifestations of dengue in puerto rico are presented from a historical perspective. dengue in puerto rico has evolved from a clinically mild illness in the 1960's to a devastating disease with hemorrhagic manifestations in the 1980's an ...19873313491
dengue haemorrhagic fever in malaysia: a review.the historical background, epidemiology and changing pattern of clinical disease as seen in malaysia is reviewed. the preliminary results of the longitudinal study of epidemiology of dengue in malaysia is also presented. studies led by rudnick et al. over some 18 years have established that the disease is endemically transmitted by both aedes aegypti and aedes albopictus causing illnesses ranging from mild febrile episodes through classical dengue fever, dengue haemorrhagic fever and the dengue ...19873324361
characterization of the toxicity and cytopathic specificity of a cloned bacillus thuringiensis crystal protein using insect cell culture.an insecticidal protein gene from bacillus thuringiensis var. aizawai was cloned in escherichia coli. the cloned gene expressed at a high level and the synthesized protein appeared as an insoluble, phase-bright inclusion in the cytoplasm. these inclusions were isolated by density gradient centrifugation, the isolated protein was activated in vitro by different proteolytic regimes and the toxicity of the resulting preparations was studied using insect cells grown in tissue culture. the inclusions ...19873330756
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