the infectivity of microfilariae of brugia pahangi of different ages to aedes transferring microfilariae of brugia pahangi which had been born over a 24-hour period in the peritoneal cavities of jirds (meriones unguiculatus) to the blood circulation of other jirds, infections of known age were tested for their ability to develop into third-stage larvae (l3) in mosquitoes aedes aegypti. microfilariae less than three days old were not able to develop to l3. microfilariae which had been in circulation for three days to six months were capable of developing if ingested.19827096971
[on an outbreak caused by dengue type 4 virus, in thio, new caledonia. epidemiological and clinical aspects (author's transl)].after imported cases, a dengue outbreak, caused by type 4 virus, affected 11 per cent of the habitants of thio, new caledonia. distribution of cases by sex, by ethnic and age group, by locality and by week is established on cases confirmed by serology and/or by virus isolation. clinical aspect was classical but liver and digestive tract of patients were frequently affected. five haemorrhagic forms were observed. aedes aegypti was found in each visited house; pooled specimens were found infected ...19827105285
infection of aedes aegypti with zygotes of plasmodium gallinaceum fertilized in vitro.female gametes of plasmodium gallinaceum fertilized in vitro, cleaned of all other blood constituents, resuspended in blood, and fed to aedes aegypti through a membrane were infective. at the lowest zygote concentration, 10(4)/ml, nearly every ingested parasite produced an oocyst. as the concentration ingested increased, efficiency to infect diminished, until above 10(7) zygotes/ml the number of oocysts produced became constant. this method should be valuable for determining the nutrient require ...19827119992
estimation of the amount of venezuelan equine encephalomyelitis virus transmitted by a single infected aedes aegypti (diptera: culicidae). 19827120306
dengue-2 vaccine: infection of aedes aegypti mosquitoes by feeding on viremic recipients.colonized aedes aegypti mosquitoes were fed on voluntary recipients of an experimental, live, attenuated, dengue type 2 (pr 159/s-1) vaccine to estimate the frequency of vector infection and the stability of the virus in mosquitoes. two volunteers were viremic at the time of mosquito feeding, but only two of 114 mosquitoes that took a viremic blood meal became infected with the vaccine virus. strains of virus recovered from the bodies of the mosquitoes and the volunteer's blood retained the temp ...19827149107
dengue-2 vaccine: oral infection, transmission, and lack of evidence for reversion in the mosquito, aedes aegypti.the dengue-2 vaccine virus (s-1), and its parent virus (pr-159), were compared for their ability to infect orally, to replicate in, and subsequently to be transmitted by aedes aegypti mosquitoes. the vaccine virus was markedly less efficient in its ability to infect mosquitoes orally. after ingesting infectious bloodmeals containing 3, 7 to 8.2 log10mid50/ml of the respective viruses, 56% (220/396) of the mosquitoes became orally infected with the parent virus contrasted with 16% (66/397) for th ...19827149108
laboratory evaluation of bacillus thuringiensis var. israelensis serotype h-14 against mosquito larvae with particular reference to aedes aegypti. 19827153478
transmission of venezuelan equine encephalomyelitis virus by aedes aegypti (diptera: culicidae) to mice previously exposed to vector antigens. 19827154017
a kinetic and ultrastructural comparison of alphavirus infection of cultured mosquito and vertebrate cells.vero cells and aedes pseudoscutellaris cells showed rapid production of semliki forest virus (sfv) whereas in aedes aegypti and anopheles stephensi cells no rapid production of sfv was observed. ultrastructurally the only virally induced cell inclusion in early infection was the cytopathic vacuole type 1. later in infection, in mosquito cells, electron-dense bodies appear and budding of new virions appears to be very efficient. in vero cells large accumulations of envelope proteins and nucleocap ...19827154145
well breeding behaviour of aedes aegypti. 19827166362
the ultrastructure of the larval malpighian tubules of a saline-water mosquito.the larval malpighian tubules of the saline-water mosquito aedes taeniorhynchus were examined using light and electron microscopy. the tubules contain two cell types; primary cells and stellate cells. primary cells are characterized by their size (70 microns x 70 microns x 10 microns) and an abundance of intracellular membrane-bound crystals. two types of microvilli are found on the luminal surface of the primary cells: (1) small microvilli containing core microfilaments and extensions of endopl ...19827170712
multiplication of coxiella burnetii in aedes aegypti. 19827174009
distribution and density of aedes aegypti (l) and aedes albopictus (skuse) in sarawak. 19827176997
[distribution of aedes aegypti in china and its comprehensive control]. 19827185486
[dipetalonema dessetae in proechimys oris. ii. evaluation of the model for pharmacologic investigations of antifilarial chemotherapy (author's transl)].dipetalonema dessetae in proechimys oris is a new model of rodent feafilariasis with several interesting features with respect to its utilisation in antifilarial pharmacology. 1. in the first part of these studies, it has been shown that the final host of the filaria, a rodent, was easy to breed. a prolific mosquito aedes aegypti was an effective vector, and with the selected mode of infection i.e. 200 infesting larvae subcutaneously injected, 80% of the rodents were infected. 2. from 90 to 150 ...19827200173
[intake of microfilariae by the vector in the case of a low microfilareamia (author's transl)].the study of the intake of microfilariae of dipetalonema dessetae by aedes aegypti leads to two conclusions with respect to the microfilaraemia: --there is no concentration of microfilariae in the uptake of blood by aedes. --the microfilariae are nearly homogeneously distributed in the vertebrate host blood available to the vector for feeding. such a distribution of microfilariae in the cutaneous blood supply of the host gives the maximum chance for a mosquito to become infected when taking a bl ...19827200752
brugia pahangi: development in aedes aegypti reared axenically on a defined synthetic diet. 19817202630
[attractant properties of peptides for oviparous female aedes aegypti and culex pipiens molestus mosquitoes]. 19807207386
a preliminary survey of aedes aegypti in selangor, peninsular malaysia. 19807219273
[effect of conditions and duration of aedes aegypti densonucleosis virus storage on its infective properties]. 19817253970
factors affecting syncytial development in aedes pseudoscutellaris cells by dengue viruses.several factors that were suspected of affecting the development of syncytia in cultured aedes pseudoscutellaris cells inoculated with dengue viruses were studied. the results indicated that fresh media (less than 1 week old), low cell density at inoculation (2.8 x 10(5) cells/cm2), and low cell passage level (less than 52 passages) favored the development of syncytia. all three types (1, 2, and 3) of dengue viruses tested could be isolated from human sera by aedes pseudoscutellaris cell culture ...19817258498
morphogenesis of yellow fever virus in aedes aegypti cultured cells. ii. an ultrastructural study.the growth and intracytoplasmic development of two yellow fever virus strains (wild and french neurotropic) were studied in aedes aegypti cells (clone c 17). despite a longer period of latency for the vaccine virus, infected cells appeared similar. the cisternae of the rough endoplasmic reticulum (rer) were swollen and formed vesicles which contained the virus. this rer appeared to be the predominant locus of viral synthesis and maturation. cytopathic effect appeared when the cells were filled w ...19817283005
[ph variations in the midgut of aedes aegypti in relation to bacillus thuringiensis var. israelensis (serotype h14) crystal intoxication].after feeding aedes aegypti larvae with b. thuringiensis var. israelensis crystals the very alkaline ph (greater than or equal to 10) of the anterior midgut remains stable during the first twenty minutes, in spite of important cytological damage. thereafter, the ph drops to surround the neutrality and the death occurs. these results are discussed according to the knowledge on the action of b. thuringiensis var. israelensis.19817296735
laboratory transmission of brugia pahangi by nulliparous aedes aegypti (diptera: culicidae). 19817299793
relative activity of bacillus thuringiensis var. kurstaki and b. thuringiensis var. israelensis against larvae of aedes aegypti, culex quinquefasciatus, trichoplusia ni, heliothis zea, and heliothis virescens. 19817320315
infection of aedes aegypti with brugia pahangi administered by enema: results of quantitative infection and loss of infective larvae during blood feeding.a technique for infecting mosquitoes with known numbers of brugia pahangi microfilariae by enema is described. virtually all mosquitoes receiving three microfilariae or more by this route contained infective larvae 10 days later. within a range of 1 to 40 microfilariae, numbers of infective larvae recovered (y) were related to the numbers of microfilariae administered (x) by the equation log10y=0.04 + 0.84 log10x. mosquitoes feeding on sugar for up to 20 days did not lose a significant number of ...19817324102
transmission of ross river virus by aedes polynesiensis and aedes aegypti.laboratory studies were carried out with two geographic strains of aedes polynesiensis and one strain of aedes aegypti to determine whether they could transmit ross river virus (rrv). both species were shown to be good vectors of rrv, but ae. polynesiensis was the most susceptible. ae. polynesiensis represents a new vector for this virus and the epidemiologic implications of rrv spread by both mosquito species are discussed.19817325287
sequential development changes in microfilariae of subperiodic brugia malayi to infective larvae in susceptible strain of aedes aegypti (macdonald). 19817343589
comparative sensitivity of mosquito inoculation and mammalian cell culture for isolation of some arboviruses in indonesia.the sensitivity of parenteral inoculation of colony reared male aedes aegypti and mammalian cell cultures for isolation of japanese encephalitis virus and dengue virus were compared. the mosquito inoculation technique proved to be more sensitive for the isolation of dengue virus from the sera of febrile patients than did the mammalian cell cultures (vero and bhk21) employed in these studies. mosquito inoculation proved to be no more sensitive that the mammalian system for the isolation of japane ...19817344103
the reinvasion of colombia by aedes aegypti: aspects to remember. 19807386716
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
yellow fever in the gambia, 1978--1979: epidemiologic aspects with observations on the occurrence of orungo virus 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 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
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 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
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
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
dietary control of late trypsin gene transcription in aedes 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
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
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
venezuelan equine encephalitis--colombia, 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
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 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
risk factors for dengue infection during an outbreak in yanes, puerto rico 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
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
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
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
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
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
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 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 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
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
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, 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
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
emergency control of aedes aegypti in the dominican republic using the scorpion 20 ulv forced-air 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
a convenient mosquito membrane feeding system.a convenient, electronically controlled, in situ, membrane feeding system is described. evaluation of the system for feeding single pair-mated aedes aegypti with defibrinated, refrigerated pig blood indicated no significant difference from mouse-fed controls in rat of egg maturation, fecundity, or pupal yield. the feeding system is also suitable for use with substitute protein meals.19947807091
infection, dissemination, transmission, and biological attributes of dengue-2 pdk53 candidate vaccine virus after oral infection in aedes aegypti.the capacity for oral infection, dissemination, and transmission of the dengue-2 candidate vaccine virus den-2 pdk53 and an isolate from a vaccinate individual, den-2 ia8, were compared with the parent strain den-2 16681. capacity for oral infection and dissemination to the brain and salivary gland tissues were significantly lower in the first two than in the parent strain (p < 0.001). replication was more than 100 times higher for the parent strain when compared with the dengue-2 candidate vacc ...19947810824
mosquito transposable elements.most of the transposons so far characterized from mosquito genomes are retroelements which seem to be distributed worldwide. the juan transposons constitute a family of non-ltr retroelements, or line-retroposons, which are dispersed in the genomes of several mosquito species. three different juan subfamilies have been characterized, each being amplified in the genomes of many strains, if not all, of a given mosquito species. these subfamilies have been designated respectively juan-c in culex pip ...19947813911
salivarectomy effects on the ingestion of brugia pahangi (nematoda: filarioidea) microfilariae by susceptible and refractory strains of aedes aegypti (diptera: culicidae).ingestion of brugia pahangi buckley & edeson microfilariae by susceptible (liverpool) and refractory (bora-bora) strains of salivary duct-severed aedes aegypti (l.) was investigated. the transection at either the salivary common duct or the two lateral ducts of mosquitoes did not affect the mean number of microfilariae nor the mean amount of blood ingested per mosquito. these results indicated that mosquito salivary secretion did not have a chemotropic effect on microfilariae.19947815410
[dengue epidemic in new caledonia (1989). environmental factors and prevention].an extensive dengue epidemic was reported in new caledonia en 1989. environmental factors (temperature and rainfalls) directly controlled the mosquitos population at the end of 1988. the introduction of a new dengue virus, transmitted by aedes aegypti, was responsible for an epidemic that occurred in january-april 1989 and lasted until july 1989. the estimated number of cases was 25,000 and the attack rate was close to 120 per thousand inhabitants for a six month-period. the epidemic involved ma ...19937819798
[current situation of yellow fever in latin america].yellow fever endemicity is currently stabilized in south america: an average of 115 cases has officially been notified each year since 25 years (between 12 and 304 annual cases). these figures are underevaluated but no epidemic has been observed since 1983. only sporadic or limited grouped cases have been reported. all declared cases correspond to people who have been infected within sylvatic areas, mainly adult forestmen. within the last years, the majority of cases have occurred in peru and bo ...19937819801
comparative study of hemolymph phenoloxidase activity in aedes aegypti and anopheles quadrimaculatus and its role in encapsulation of brugia malayi microfilariae.hemolymph phenoloxidase activity of sugar-fed and blood-fed females of anopheles quadrimaculatus and aedes aegypti showed similar characteristics. phenoloxidase was present as an inactive proenzyme in both mosquito species and was partially activated during collection of the hemolymph. in both mosquito species, phenoloxidase activity was modulated by different buffers and activated phenoloxidase did not need ca2+. enzymatic activity was higher in the hemocytes than in the plasma in both mosquito ...19947828033
larvicidal microcystin toxins of cyanobacteria affect midgut epithelial cells of aedes aegypti mosquitoes. 19947841498
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