dengue transmission risk maps of argentina.dengue is an emerging disease that has become important in argentina because of its vector's presence (aedes aegypti) and its endemicity in neighbouring countries. thematic maps were built for argentina considering four main factors: population susceptibility to dengue virus infection (population density); entrance of the virus from endemic countries (main roads and airports); conditions for the vector (urbanization, altitude, minimum, maximum and mean daily temperatures) and virus extrinsic inc ...200111299033
limited potential for transmission of live dengue virus vaccine candidates by aedes aegypti and aedes evaluate the transmission risk of four live dengue (den) vaccine candidates developed by the u.s. army (den-1, 45az5 pdk 20; den-2, s16803 pdk 50; den-3, ch53489 pdk 20; and den-4, 341750 pdk 20), we tested 3,010 aedes aegypti and 1,576 aedes albopictus mosquitoes blood-fed on 21 volunteers who had been administered one of the four vaccine candidates or the licensed yellow fever (yf) vaccine (17d). we used an indirect immunofluorescence assay (ifa) to detect den or yf viral antigen in the hea ...200011304057
mosquito allergy: recombinant mosquito salivary antigens for new diagnostic patients with mosquito allergy, lack of a readily available, sensitive, specific, safe test is the major obstacle to accurate diagnosis. three recombinant mosquito salivary antigens, raed a 1 (68 kd), raed a 2 (37 kd) and raed a 3 (30 kd), from aedes aegypti have been cloned, expressed, purified and characterized. all three recombinant antigens are shared by aedes vexans and other mosquito species, and all have been found to have biologic activity in humans. in recent studies, 43% of 28 mosqu ...200111307029
anti-mosquito midgut antibodies block development of plasmodium falciparum and plasmodium vivax in multiple species of anopheles mosquitoes and reduce vector fecundity and survivorship.the mosquito midgut plays a central role in the sporogonic development of malaria parasites. we have found that polyclonal sera, produced against mosquito midguts, blocked the passage of plasmodium falciparum ookinetes across the midgut, leading to a significant reduction of infections in mosquitoes. anti-midgut mabs were produced that display broad-spectrum activity, blocking parasite development of both p. falciparum and plasmodium vivax parasites in five different species of mosquitoes. in ad ...200111309510
a preliminary study of the population genetics of aedes aegypti (diptera: culicidae) from mexico using microsatellite and aflp markers.dengue fever recently reemerged in the americas. because vaccines are still under development, dengue prevention depends entirely on vector control. since aedes aegypti (linnaeus, 1762) is the principal vector of this arbovirus, knowledge of the genetic structure of the insect is therefore required to maintain effective vector control strategies and to estimate levels of gene flow from which movement can be inferred. this preliminary study uses microsatellite and amplified fragment length polymo ...200111311187
detection and culture of bartonella quintana, serratia marcescens, and acinetobacter spp. from decontaminated human body part of a survey for trench fever among homeless people in marseilles, france, we attempted isolation of bartonella quintana from body lice. a decontamination protocol of immersion in 70% ethanol with 0.2% iodine was devised and was tested with a laboratory colony of body lice. lice which had been experimentally contaminated with either escherichia coli, staphylococcus epidermidis, or acinetobacter spp. were successfully decontaminated, and this process did not prevent the culture of b. quint ...200111325978
plant biology in the the beginning of modern plant biology, plant biologists followed a simple model for their science. this model included important branches of plant biology known then. of course, plants had to be identified and classified first. thus, there was much work on taxonomy, genetics, and physiology. ecology and evolution were approached implicitly, rather than explicitly, through paleobotany, taxonomy, morphology, and historical geography. however, the burgeoning explosion of knowledge and great adva ...200111344291
indoor thermal fogging application of pesguard fg 161, a mixture of d-tetramethrin and cyphenothrin, using portable sprayer against vector mosquitoes in the tropical environment.indoor bioefficacy of the thermal fogging application of pesguard fg 161, a formulation containing both knockdown and killing agents (active ingredient [ai]: d-tetramethrin 4% [w/w] and cyphenothrin 12% [w/w]) was compared with resigen5 (ai: s-bioallethrin 0.8% [w/w], permethrin 125/75] 18.7% [w/w], and piperonyl butoxide 16.8% [w/w]), another pyrethroid formulation, as larvicides and adulticides against aedes aegypti, aedes albopictus, anopheles sinensis, and culex quinquefasciatus using a port ...200111345415
evaluation of liquid bacillus thuringiensis var. israelensis products for control of australian aedes arbovirus vectors.laboratory bioassay studies were conducted in southeast queensland, australia, on the efficacy of teknar, vectobac 12as, and cybate (active ingredient: 1,200 international toxic units bacillus thuringiensis var. israelensis [bti]) against 3rd instars of the arbovirus vectors aedes aegypti, ae. notoscriptus, ae. vigilax, and ae. camptorhynchus. probit analyses were then used to determine ld50 (median lethal dose), ld50, and lethal dose ratios (ldr). aedes aegypti and ae. notoscriptus, both contai ...200111345425
knockout of the rodent malaria parasite chitinase pbcht1 reduces infectivity to mosquitoes.during mosquito transmission, malaria ookinetes must cross a chitin-containing structure known as the peritrophic matrix (pm), which surrounds the infected blood meal in the mosquito midgut. in turn, ookinetes produce multiple chitinase activities presumably aimed at disrupting this physical barrier to allow ookinete invasion of the midgut epithelium. plasmodium chitinase activities are demonstrated targets for human and avian malaria transmission blockade with the chitinase inhibitor allosamidi ...200111349074
disruption of plasmodium falciparum chitinase markedly impairs parasite invasion of mosquito initiate invasion of the mosquito midgut, plasmodium ookinetes secrete chitinolytic activity to penetrate the peritrophic matrix surrounding the blood meal. while ookinetes of the avian malaria parasite plasmodium gallinaceum appear to secrete products of two chitinase genes, to date only one chitinase gene, pfcht1, has been identified in the nearly completed plasmodium falciparum strain 3d7 genome database. to test the hypothesis that the single identified chitinase of p. falciparum is neces ...200111349075
transmission efficiency of culex quinquefasciatus and aedes aegypti to wuchereria bancrofti infection: an experimental study.present study was undertaken to evaluate the suitability of natural (culex quinquefasciatus) and experimental (aedes aegypti) vectors for supporting the development of w. bancrofti larvae for onward transmission. both the species permitted development of w. bancrofti mf to infective larvae (l3) within 11 to 13 days. the mf intake by both the species of mosquitoes was directly related to mf density in donor's blood. culex exhibited higher l3 recovery than aedes. in aedes maximum percent l3 develo ...200111349538
mechanical transmission of lumpy skin disease virus by aedes aegypti (diptera: culicidae).aedes aegypti female mosquitoes are capable of the mechanical transmission of lumpy skin disease virus (lsdv) from infected to susceptible cattle. mosquitoes that had fed upon lesions of lsdv-infected cattle were able to transmit virus to susceptible cattle over a period of 2-6 days post-infective feeding. virus was isolated from the recipient animals in 5 out of 7 cases. the clinical disease recorded in the animals exposed to infected mosquitoes was generally of a mild nature, with only one cas ...200111349983
genetic relationships among aedes aegypti (diptera: culicidae) populations from argentina using random amplified polymorphic dna polymerase chain reaction markers.random amplified polymorphic dna polymerase chain reaction (rapd-pcr) polymorphism was analyzed in five aedes aegypti (l.) populations from argentina and one from puerto rico to estimate levels of intraspecific polymorphism and genetic relatedness. allele frequencies were estimated assuming that rapd products segregate as dominants and that genotype frequencies at those loci are in hardy-weinberg equilibrium. mean expected heterozygosity (he) was 0.350; f(st) values were significant at all loci ...200111372960
why do female aedes aegypti (diptera: culicidae) feed preferentially and frequently on human blood?adult female aedes aegypti (l.), the vector of dengue and yellow fever viruses, have an affinity for feeding on human blood and a tendency to forego feeding on sugar. this observation challenges two tenets of mosquito biology: (1) mosquitoes imbibe plant carbohydrates for synthesis of energy reserves and blood for reproduction and (2) egg production is reduced when mosquitoes feed on human blood compared with blood from other species. sub-optimal amounts of the amino acid isoleucine in human blo ...200111372967
survival of aedes aegypti (diptera: culicidae) eggs in surface and subterranean breeding sites during the northern queensland dry season.the effect of a protracted dry season on the viability of ae. aegypti (l.) eggs was examined in townsville, northern queensland, australia. eggs were placed in several different surface and subterranean larval habitats; and after four dry season months, only 1-10% of eggs remained viable in the surface and subterranean sites, respectively. low humidity and predation by periplaneta americana (l.) were the major causes of egg mortality in eggs in surface sites. p. americana was the most significan ...200111372971
[dengue imported from paraguay to buenos aires. clinical and epidemiological report of 38 cases].thirty eight patients with classic dengue fever, were studied from december 1999 up to april 2000. all of them acquired the infection in paraguay; 66% of patients arrived at buenos aires metropolitan area within the viremia period. given aedes aegypti abundance in the region they represent a high risk for local transmission. unusual clinical findings in these patients were diarrhea (29%), transitory rise of seric aspartate aminotransferase (52%) and pruritic rash in all cases. only 15.7% showed ...200111374134
environmental characteristics of the cemeteries of buenos aires city (argentina) and infestation levels of aedes aegypti (diptera: culicidae).cemeteries with many water-filled containers, flowers, sources of human blood, and shade are favorable urban habitats for the proliferation of aedes aegypti, a vector of yellow fever and dengue. a total of 22,956 containers was examined in the five cemeteries of the city of buenos aires, argentina. the vector was found in four cemeteries that showed an average infestation level of 5.5% (617 positive out of 11,196 water-filled containers). the four cemeteries positive for ae. aegypti showed signi ...200111391417
dengue/dhf: an emerging disease in india.dengue/dhf is an emergent disease in india and some parts of country are endemic and periodically contributing annual outbreaks of dengue/dhf. dengue infection manifests as undifferentiated fever, dengue haemorrhagic fever (dhf) which leads to hospitalization large number of people in a localized area. there is high mortality and morbidity associated with the onset of each dengue outbreak leading to great socio-economic impact. the prevention and control of dengue outbreak depends upon the prope ...200011407002
breeding habitats and larval indices of aedes aegypti and ae. albopictus in the residential areas of calcutta city.aedes aegypti and ae. albopictus larvae were found breeding in almost all indoor and outdoor, temporary and/or permanent collections of water, either alone or in association with each other in residential areas of the city, the former throughout the year (june'97-may'98) and the latter during monsoons and post-monsoons only. ae. aegypti showed preference for breeding in chowbachhas, indoors and ae. albopictus for collections of water in flower pots and discarded containers and outdoors. the larv ...200011407003
essential role of cyclization sequences in flavivirus rna replication.a possible role in rna replication for interactions between conserved complementary (cyclization) sequences in the 5'- and 3'-terminal regions of flavivirus rna was previously suggested but never tested in vivo. using the m-fold program for rna secondary-structure predictions, we examined for the first time the base-pairing interactions between the covalently linked 5' genomic region (first ~160 nucleotides) and the 3' untranslated region (last ~115 nucleotides) for a range of mosquito-borne fla ...200111413342
the effect of lactic acid on odour-related host preference of yellow fever a behavioural study we have investigated the role of lactic acid for the host preferences of yellow fever mosquitoes (aedes aegypti) by comparing the attractiveness of rubbings from the hands of different human individuals and extracts obtained from skin rubbings from different mammals (bos primigenius f. taurus, capra aegagrus f. hircus, felis silvestris f. catus and homo sapiens). certain human individuals were consistently more attractive to mosquitoes than others. addition of lactic acid ...200111418498
five new prenylated stilbenes from the root bark of lonchocarpus chiricanus.besides the known compounds longistylines c (1), d (2), and 3,5-dimethoxystilbene (5), five new prenylated stilbenes, named chiricanines a--e (3, 4, 6--8), have been isolated from the root bark of lonchocarpus chiricanus. their structures were resolved on the basis of spectrometric methods including (1)h, (13)c, and 2d nmr experiments and mass spectrometry. compound 3 was the only prenylated stilbene to demonstrate antifungal effects against cladosporium cucumerinum. four of the isolated compoun ...200111421729
expression of the p20 gene from bacillus thuringiensis h-14 increases cry11a toxin production and enhances mosquito-larvicidal activity in recombinant gram-negative bacteria.experimental analyses with recombinant escherichia coli and pseudomonas putida transformed with plasmids bearing genes coding for the cry11a toxin and p20 protein from bacillus thuringiensis h-14 showed that cells producing both proteins were more toxic when fed to third-instar aedes aegypti larvae than were cells expressing cry11a alone; the 50% lethal concentrations were in the range of 10(4) to 10(5) cells/ml. western blots revealed a higher production of cry11a when the p20 gene was coexpres ...200111425714
cyt1ab1 and cyt2ba1 from bacillus thuringiensis subsp. medellin and b. thuringiensis subsp. israelensis synergize bacillus sphaericus against aedes aegypti and resistant culex quinquefasciatus (diptera: culicidae).the interaction of two cytolytic toxins, cyt1ab from bacillus thuringiensis subsp. medellin and cyt2ba from bacillus thuringiensis subsp. israelensis, with bacillus sphaericus was evaluated against susceptible and resistant culex quinquefasciatus and the nonsensitive species aedes aegypti. mixtures of b. sphaericus with either cytolytic toxin were synergistic, and b. sphaericus resistance in c. quinquefasciatus was suppressed from >17,000- to 2-fold with a 3:1 mixture of b. sphaericus and cyt1ab ...200111425753
[urbanization and dengue ecology].demographic changes occurring in underdeveloped countries due to intense rural-urban migration since the 1960s have resulted in overcrowded cities with multiple deficiencies, particularly in housing and basic sanitation. some 20% of the population in large and medium-sized cities live in slums or under similar conditions. lack of regular water supply and public garbage collection foster the proliferation of potential breeding sites for aedes aegypti (the main mosquito vector for dengue), includi ...200111426270
comparative linkage map development and identification of an autosomal locus for insensitive acetylcholinesterase-mediated insecticide resistance in culex tritaeniorhynchus.a comparative linkage map for culex tritaeniorhynchus was constructed based on restriction fragment length polymorphism markers using cdnas from aedes aegypti. linear orders of marker loci in cx. tritaeniorhynchus were identical to culex pipiens wherein chromosomes 2 and 3 reflect whole-arm rearrangements compared to a. aegypti. however, the sex determination locus in cx. tritaeniorhynchus maps to chromosome 3, in contrast to cx. pipiens and ae. aegypti where it is located on chromosome 1. our r ...200111437911
microsatellite loci are not abundant in all arthropod genomes: analyses in the hard tick, ixodes scapularis and the yellow fever mosquito, aedes aegypti.plasmid libraries enriched for microsatellites were generated in the tick, ixodes scapularis and in the mosquito aedes aegypti. libraries were enriched for genomic dna containing (ac)n, (ag)n, (atg)n, (cag)n, (tag)n, (aat)n, (ctgy)n or (gata)n motifs. clones containing each motif were sequenced in both species for pcr primer design. in i. scapularis, most primers amplified a single locus and alleles varied in the number of microsatellite repeats and segregated as codominant markers. in contrast ...200111437914
sindbis virus-induced silencing of dengue viruses in mosquitoes.aedes aegypti were injected intrathoracically with double subgenomic sindbis (dssin) viruses with inserted sequences derived from the genome of one or more of the four dengue (den) virus serotypes. mosquitoes were highly resistant to challenge with homologous den viruses from which the effector sequences were derived, and resistance to den viruses was independent of the orientation of the effector rna. dssin viruses designed to express rna derived from the premembrane coding region of den-2 prev ...200111437918
the salivary adenosine deaminase activity of the mosquitoes culex quinquefasciatus and aedes aegypti.a cdna coding for a protein with significant similarity to adenosine deaminase (ada) was found while randomly sequencing a cdna library constructed from salivary gland extracts of adult female culex quinquefasciatus. prompted by this result, we found high ada activities in two culicine mosquitoes, culex quinquefasciatus and aedes aegypti, but not in the anopheline anopheles gambiae. homogenates from culex quinquefasciatus also have an amp deaminase activity that is three times greater than the a ...200111441041
interaction between host complement and mosquito-midgut-stage plasmodium berghei.after ingestion by mosquitoes, gametocytes of malaria parasites become activated and form extracellular gametes that are no longer protected by the red blood cell membrane against immune effectors of host blood. we have studied the action of complement on plasmodium developmental stages in the mosquito blood meal using the rodent malaria parasite plasmodium berghei and rat complement as a model. we have shown that in the mosquito midgut, rat complement components necessary to initiate the altern ...200111447187
identification of a polymorphic mucin-like gene expressed in the midgut of the mosquito, aedes aegypti, using an integrated bulked segregant and differential display analysis.the identification of putative differentially expressed genes within genome regions containing qtl determining susceptibility of the mosquito, aedes aegypti, to the malarial parasite, plasmodium gallinaceum, was investigated using an integrated, targeted approach based on bulked segregant and differential display analysis. a mosquito f2 population was obtained from pairwise matings between the parasite-susceptible red strain and the resistant moyo-r substrain. dna from female carcasses was used ...200111454761
[epidemiology of dengue in salvador-bahia, 1995-1999].since 1981, brazil has registered dengue epidemic and simultaneous circulation of the den-1 and den-2 serotypes in over 2,700 municipalities. in salvador- bahia, located in the northeastern region of the country, two epidemic outbreaks occurred in the years of 1995 and 1996, with further endemic spread of the disease. this study analyses the incidence of the virosis within this municipal area, from 1995 to 1999, considering, among other variables, its distribution in the sanitary districts and d ...200111460213
construction, safety, and immunogenicity in nonhuman primates of a chimeric yellow fever-dengue virus tetravalent vaccine.we previously reported construction of a chimeric yellow fever-dengue type 2 virus (yf/den2) and determined its safety and protective efficacy in rhesus monkeys (f. guirakhoo et al., j. virol. 74:5477-5485, 2000). in this paper, we describe construction of three additional yf/den chimeras using premembrane (prm) and envelope (e) genes of wild-type (wt) clinical isolates: den1 (strain puo359, isolated in 1980 in thailand), den3 (strain pah881/88, isolated in 1988 in thailand), and den4 (strain 12 ...200111462001
tmof-like factor controls the biosynthesis of serine proteases in the larval gut of heliothis virescens.proteolytic enzyme biosynthesis in the midgut of the 4th instar larva of heliothis virescens is cyclical. protease activity increases immediately after the molt from the 3rd to the 4th instar larvae and declines just before the molt into the 5th instar. characterization of the midgut proteases using soybean tryspin inhibitor (sbti) bowman birk inhibitor (bbi) 4-(2-aminoethyl)benzensulfonylfluoride (aebsf) and n-tosyl-l-phenylalanine chloromethylketone (tpck) indicate that protease activity is mo ...200111462221
both mosquito-derived xanthurenic acid and a host blood-derived factor regulate gametogenesis of plasmodium in the midgut of the mosquito.gametogenesis of plasmodium in vitro can be induced by the combined stimulus of a 5 degrees c fall in temperature and the presence of xanthurenic acid (xa). in-vitro experiments showed that p. gallinaceum (ec(50)=80 nm) is much more sensitive to xa than p. berghei (9 microm), p. yoelii (8 microm), and p. falciparum (2 microm). however, in the mosquito vector, we do not know whether the temperature shift and xa are the only gametocyte-activating factors (gaf), nor do we know with certainty the tr ...200111463462
entomopathogenic activities of environmental isolates of bacillus thuringiensis against dipteran larvae.twenty-five field isolates of bacillus thuringiensis from the lower silesia region of poland, the osola plain, and phylloplane niches and soil samples from the karkonosze national park were tested for insecticidal activity against larvae of the dipterans aedes aegypti, drosophila melanogaster and musca domestica. the spore-crystal mixture of b. thuringiensis finitimus (soil isolate) killed nearly half of the fourth instar larvae of ae. aegypti. similar mortality of between 39-61% was recorded af ...200111469180
repellency of volatile oils from plants against three mosquito vectors.volatile oils extracted by steam distillation from four plant species (turmeric (curcuma longa), kaffir lime (citrus hystrix), citronella grass (cymbopogon winterianus) and hairy basil (ocimum americanum)), were evaluated in mosquito cages and in a large room for their repellency effects against three mosquito vectors, aedes aegypti, anopheles dirus and culex quinquefasciatus. the oils from turmeric, citronella grass and hairy basil, especially with the addition of 5% vanillin, repelled the thre ...200111469188
detection of dengue viral rna using a nucleic acid sequence-based amplification assay.faster techniques are needed for the early diagnosis of dengue fever and dengue hemorrhagic fever during the acute viremic phase of infection. an isothermal nucleic acid sequence-based amplification (nasba) assay was optimized to amplify viral rna of all four dengue virus serotypes by a set of universal primers and to type the amplified products by serotype-specific capture probes. the nasba assay involved the use of silica to extract viral nucleic acid, which was amplified without thermocycling ...200111473994
detection of dengue viruses in field caught male aedes aegypti and aedes albopictus (diptera: culicidae) in singapore by type-specific pcr.field male aedes aegypti (l.) and aedes albopictus (skuse) adults caught from fixed monitoring stations weekly for 1 yr were screened for dengue viruses (den-1, den-2, den-3, and den-4). the assay was carried out using a single-step reverse transcription (or transcriptase)-polymerase chain reaction (pcr) (rt-pcr) followed by a semi-nested pcr using an upstream consensus primer and four type-specific primers within the nonstructural protein three gene (ns3) of dengue viruses. the diagnostic fragm ...200111476326
analysis of survival of young and old aedes aegypti (diptera: culicidac) from puerto rico and generally is assumed that the daily probability of survival of wild adult mosquitoes is independent of age. to test this assumption we conducted mark-release-recapture studies in puerto rico and thailand to determine if estimated daily survival rates between two different age cohorts of the dengue vector aedes aegypti (l.) were the same. survivorship was estimated with nonlinear regression analysis using bootstrapping to obtain estimates of errors. initial recapture success of the younger coh ...200111476334
efficacy of australian quarantine procedures against the mosquito aedes aegypti.methods employed by australian quarantine officers to control aedes mosquitoes in containers were tested against all stages of aedes aegypti. saltwater emersion killed all larvae but not pupae or eggs that were briefly exposed. swimming pool chlorine, methyl bromide fumigation, and permethrin (2% active ingredient) spray provided 100% mortality of eggs, larvae, and pupae. aerosol sprays incorporating synthetic pyrethrins are practical and also provide effective control of adults.200111480817
concurrent control of mosquitoes and domestic pests by use of deltamethrin-treated curtains in the new delhi municipal committee, india.a field trial was conducted in block f of the moti bagh area of new delhi municipal committee to demonstrate composite control of anopheles stephensi and aedes aegypti by spraying deltamethrin at 100 mg/m2 on window and door curtains of habitations. results revealed drastic reduction (87.9-93.7%, p < 0.05) of target species in the experimental area. the impact of deltamethrin-treated curtains was also evident against nontarget species (67.9-85.7%. p < 0.05). treated curtains provided 100% kill o ...200111480821
the use of sticky ovitraps to estimate dispersal of aedes aegypti in northeastern mexico.a newly designed sticky ovitrap was used to determine the dispersal flight of the dengue vector aedes aegypti in northeastern mexico. unfed marked females were released in the field where 100 sticky ovitraps had been positioned within a circular area 300 m in diameter. success of this method was represented by a 7.7% (31 of 401) recapture rate during a 19-day sampling period. the maximum dispersal distance was 120 m with a mean of 30.5 m +/- 4.5 sd. drastic hot and dry climatic conditions at the ...200111480827
host switching in lyssavirus history from the chiroptera to the carnivora orders.lyssaviruses are unsegmented rna viruses causing rabies. their vectors belong to the carnivora and chiroptera orders. we studied 36 carnivoran and 17 chiropteran lyssaviruses representing the main genotypes and variants. we compared their genes encoding the surface glycoprotein, which is responsible for receptor recognition and membrane fusion. the glycoprotein is the main protecting antigen and bears virulence determinants. point mutation is the main force in lyssavirus evolution, as sawyer's t ...200111483755
tick-borne langat/mosquito-borne dengue flavivirus chimera, a candidate live attenuated vaccine for protection against disease caused by members of the tick-borne encephalitis virus complex: evaluation in rhesus monkeys and in mosquitoes.langat virus (lgt), strain tp21, a naturally avirulent tick-borne flavivirus, was used to construct a chimeric candidate virus vaccine which contained lgt genes for premembrane (prem) and envelope (e) glycoprotein and all other sequences derived from dengue type 4 virus (den4). the live virus vaccine was developed to provide resistance to the highly virulent, closely related tick-borne flaviviruses that share protective e epitopes among themselves and with lgt. toward that end the chimera, initi ...200111483771
[larval susceptibility to chemical insecticides of two aedes aegypti populations].insect susceptibility has been one of the most important aspects to be monitored in public health programs for vector control. the purpose of the study is to assess the susceptibility to chemical insecticides of aedes aegypti larvae in both areas under vector control and no vector control.200111486144
[aedes aegypti (l.) population in an endemic area of dengue in southeast brazil].a aedes aegypti population from an area of dengue transmission was studied to determine mosquito's frequency, spatial distribution, parity, its ovarian development and midgut contents.200111486145
rapid elimination of gb virus c (hepatitis g virus) in the mosquito aedes aegypti.the transmissibility of the gb virus c (hepatitis g virus; hgv), a member of the flaviviridae, by a typical flavivirus vector was investigated. female mosquitoes of the species aedes aegypti were fed with hgv-infected human blood and assayed 1, 24, 48, 72 and 96 h after the blood meal for viral rna, human glyceraldehyde-3-phosphate dehydrogenase mrna, human beta-actin dna and a. aegypti actin mrna by total nucleic acid extraction, reverse transcription and pcr. viral rna had already disappeared ...200111489416
construction and characterization of a recombinant bacillus thuringiensis subsp. israelensis strain that produces cry11b.the mosquitocidal bacterium bacillus thuringiensis subsp. israelensis (bti) produces four major endotoxin proteins, cry4a, cry4b, cry11a, and cyt1a, and has toxicity in the range of many synthetic chemical insecticides. cry11b, which occurs naturally in b. thuringiensis subsp. jegathesan, is a close relative of cry11a, but is approximately 10-fold as toxic to culex quinquefasciatus. to determine whether the addition of cry11b to bti would improve its toxicity, we produced this protein in bti. hi ...200111500092
vectorial competence of aedes aegypti (linnaeus 1762) rio de janeiro strain, to dirofilaria immitis (leidy 1856).dirofilaria immitis (leidy 1856), a nematode parasite, is the etiologic agent of canine heartworm disease and mosquitoes are essential intermediate hosts. mosquito susceptibility to the worms differ with species, strains and also among individuals of the same strain. to evaluate the degree of susceptibility of rio de janeiro laboratory raised strain of aedes aegypti, we fed mosquitoes on canine blood with different densities of microfilariae (mf). there was no significant difference in the rate ...200111500754
reappearance of aedes aegypti (diptera: culicidae) in lima, peru.we report here the reappearance of aedes aegypti in the rimac district, and summarize the history of this mosquito species in peru since its first detection in 1852. on march 17 2000 were found ae. aegypti and culex quinquefasciatus in mariscal castilla town, flor de amancaes, san juan de amancaes, el altillo and santa rosa in the rimac district, lima province.200111500764
comparison between precipitin and elisa tests in the bloodmeal detection of aedes aegypti (linnaeus) and aedes fluviatilis (lutz) mosquitoes experimentally fed on feline, canine and human hosts.the identification of arthropod bloodmeals is important in many epidemiological studies, as, the understanding of the life cycle of vectors and the pathogens they transmit, as well as helping to define arthropods' control strategies. the precipitin test has been used for decades, but elisa is slowly becoming more popular. to compare the two tests for sensitivity, specificity and accuracy to detect small insect bloodmeals, aedes aegypti or ae. fluviatilis mosquitoes were fed either on feline, can ...200111500773
screening of malian medicinal plants for antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities.a total of 78 different extracts from 20 medicinal plants belonging to 14 plant families from mali were tested for their antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities. dichloromethane, methanol, water and ethanol extracts were used. tlc autobiography for antifungal activity was run with cladosporium cucumerinum and candida albicans. extracts were also tested on the larvae of the mosquitoes aedes aegypti, anopheles gambiae and culex quinquefasciatus. mollusc ...200111507731
cloning and characterization of a dopachrome conversion enzyme from the yellow fever mosquito, aedes this study we describe the purification and molecular cloning of a dopachrome conversion enzyme (dce) from the yellow fever mosquito, aedes aegypti. dce catalyzes the conversion of l-dopachrome to 5,6-dihydroxyindole in the melanization pathway. melanin biosynthesis is involved with crucial protective phenomena in mosquitoes, including egg chorion and cuticular tanning, wound healing, and the melanotic encapsulation immune response. the enzyme was purified to homogeneity by various chromatogr ...200111520691
laboratory & field evaluation of controlled release formulation of the insect repellents n,n-diethyl-m-toluamide (deet) & n,n-diethyl phenylacetamide (depa) against mosquito vectors.repellents can play a useful role in reducing the man-vector contact and help in interrupting disease transmission. newer formulations are necessary to improve the efficacy of the repellent on the treated sites for enhanced protection.200111525153
effect of bacillus thuringiensis cry1 toxins in insect hemolymph and their neurotoxicity in brain cells of lymantria dispar.little information is available on the systemic effects of bacillus thuringiensis toxins in the hemocoel of insects. in order to test whether b. thuringiensis-activated toxins elicit a toxic response in the hemocoel, we measured the effect of intrahemocoelic injections of several cry1 toxins on the food intake, growth, and survival of lymantria dispar (lepidoptera) and neobellieria bullata (diptera) larvae. injection of cry1c was highly toxic to the lymantria larvae and resulted in the complete ...200111525986
existence of hepatitis c virus in culex quinquefasciatus after ingestion of infected blood: experimental approach to evaluating transmission by mosquitoes.we used pcr to detect hepatitis c virus (hcv) rna among supernatants of ground culex quinquefasciatus mosquitoes that (i) had been fed hcv-positive blood, (ii) had been intrathoracically inoculated with hcv-positive blood, or (iii) were from homes of hepatitis c patients. hcv rna was detectable under all three conditions, but it did not replicate in mosquitoes and was not detectably transmitted during feeding.200111526176
plasmodium gallinaceum: ookinete formation and proteolytic enzyme dynamics in highly refractory aedes aegypti populations.despite significant progress in the identification of the genetic basis of the refractory phenotype, little is known about the physiological mechanism of refractoriness. this study therefore examined the physiological basis of mosquito refractoriness in the aedes aegypti/p. gallinaceum system, in which a selected refractory strain does not permit plasmodium oocyst formation. we examined the kinetics of two major proteolytic enzymes involved in blood meal digestion and the dynamics of ookinete fo ...200111527434
haemogregarine specificity in two communities of florida snakes, with descriptions of six new species of hepatozoon (apicomplexa: hepatozoidae) and a possible species of haemogregarina (apicomplexa: haemogregarinidae).five species of snakes in florida, from palm beach county in the south and alachua county 450 km to the north, occur in similar habitat but have distinctive hepatozoon species characteristic of each host species. in palm beach county, diadophis punctatus is host to hepatozoon punctatus n. sp., thamnophis sauritus sackenii to hepatozoon sauritus n. sp., and nerodia fasciata pictiventris to hepatozoon pictiventris n. sp. in alachua county, n. fasciata pictiventris is parasitized by hepatozoon fasc ...200111534655
chitinase from bacillus thuringiensis subsp. pakistani.the chitinase gene (chia71) from bacillus thuringiensis subsp. pakistani consists of an open reading frame of 1,905 nucleotides encoding 635 amino acid residues with an estimated molecular mass of 71 kda. comparison of the deduced amino acid sequence of the mature enzyme to other microbial chitinases shows a putative catalytic domain and a region with conserved amino acids similar to that of the type iii module of fibronectin and a chitin-binding domain. by activity detection of chitinase on sds ...200111549008
phylogenetic analysis of dengue-3 viruses prevalent in guatemala during 1996-1998.dengue is an acute viral disease transmitted by the aedes aegypti mosquito which is present in most tropical urban areas of the world. there are four antigenically distinct serotypes, designated dengue-1 (den-1), dengue-2 (den-2), dengue-3 (den-3) and dengue-4 virus (den-4). in this study, we determined the serotypes of dengue viruses isolated in guatemala in 1995-1998, and found that den-3 viruses appeared in 1995 and became predominant in the following three years. we then sequenced cdnas from ...200111556713
[factors that modify the larval indices of aedes aegypti in colima, mexico].in order to investigate the variables that could have the greatest impact on larval indices of aedes aegypti, the main vector of dengue, a descriptive, longitudinal study was carried out in the city of colima, which is located in the mexican pacific coastal state of the same name.200111558250
evaluation of a new tablet formulation based on bacillus thuringiensis sorovar. israelensis for larvicidal control of aedes aegypti.the effect of sunlight on the efficacy and persistence of an experimental tablet formulation based on bacillus thuringiensis sorovar. israelensis (c4p1) was evaluated against aedes aegypti larvae under simulated field conditions. the initial mortality ranged from 93 to 100%, and the residual activity (> or = 70% mortality) recorded in containers exposed to sunlight or shade were, respectively, 13-35 days and 40-54 days. the results suggest that c4p1 can provide long-term larvicidal effect and op ...200111562715
requirement of co-factors for the ligand-mediated activity of the insect ecdysteroid receptor in insects, a steroid hormone 20-hydroxyecdysone has an important role in regulating critical events such as development and reproduction. the action of 20-hydroxyecdysone is mediated by its binding to the ecdysteroid receptor (ecr), which requires a heterodimeric partner, ultraspiracle protein (usp), a homologue of the retinoid x receptor (rxr). the ecr-usp heterodimer represents a functional receptor complex capable of initiating transcription of early genes. our goal was to establish a ligand ...200111564603
detection of insecticide resistance in aedes aegypti (diptera: culicidae) from cuba and venezuela.four strains of aedes aegypti (l.), one from cuba and three from venezuela, were bioassayed for susceptibility to eight insecticides, including the organophosphates, temephos, malathion, fenthion, pirimiphos methyl, and chlorpyrifos, and the pyrethroids, deltamethrin, lambda cyhalothrin and cypermethrin, s, s, s,-tributyl phosphorotrithioate and piperonyl butoxide were used as synergists to assess the involvement of esterases and monooxygenases in organophosphate resistance. venezuelan strains h ...200111580033
indirect evidence against delayed "skip-oviposition" behavior by aedes aegypti (diptera: culicidae) in thailand.mosquitoes that do not oviposit their entire batch of eggs in one location, but choose instead to oviposit a few eggs in several different sites exhibit skip oviposition. although skip oviposition may ensure the greater distribution of progeny from an individual female and reduce sibling competition, it also uses greater maternal energy reserves, may increase the risk of adult female mortality and does not reduce other competition. to test the hypothesis that female aedes aegypti (l.) do not ovi ...200111580036
detection of dengue viral rna in aedes aegypti (diptera: culicidae) exposed to sticky lures using reverse-transcriptase polymerase chain surveillance for dengue (den) virus infected mosquitoes can be an effective way to predict the risk of dengue infection in a given area. however, doing so may pose logistical problems if mosquitoes must be kept alive or frozen fresh to detect den virus. in an attempt to simplify mosquito processing, we evaluated the usefulness of a sticky lure and a seminested reverse-transcriptase polymerase chain reaction assay (rt-pcr) for detecting den virus rna under laboratory conditions using exper ...200111580045
evolutionary relationships and systematics of the alphaviruses.partial e1 envelope glycoprotein gene sequences and complete structural polyprotein sequences were used to compare divergence and construct phylogenetic trees for the genus alphavirus. tree topologies indicated that the mosquito-borne alphaviruses could have arisen in either the old or the new world, with at least two transoceanic introductions to account for their current distribution. the time frame for alphavirus diversification could not be estimated because maximum-likelihood analyses indic ...200111581380
evaluation of biological and chemical insecticide mixture against aedes aegypti larvae and adults by thermal fogging in improve the operational efficiency of dengue vector control in singapore, larvicide and adulticide were applied together by thermal fog generator (agrofog af40). the mixture consisted of bacillus thuringiensis var. israelensis (vectobac 12 as) as biological larvicide at 1.5 l/ha and pirimiphos-methyl (actellic 50 ec) as adulticide at 100 g ai/ha, diluted 10-fold with water. aerosol of this mixture was evaluated against the mosquito aedes aegypti (l.) (diptera: culicidae) in bioassays using ca ...200111583451
ross river virus transmission, infection, and disease: a cross-disciplinary review.ross river virus (rrv) is a fascinating, important arbovirus that is endemic and enzootic in australia and papua new guinea and was epidemic in the south pacific in 1979 and 1980. infection with rrv may cause disease in humans, typically presenting as peripheral polyarthralgia or arthritis, sometimes with fever and rash. rrv disease notifications in australia average 5,000 per year. the first well-described outbreak occurred in 1928. during world war ii there were more outbreaks, and the name ep ...200111585790
tsetse immune responses and trypanosome transmission: implications for the development of tsetse-based strategies to reduce trypanosomiasis.tsetse flies are the medically and agriculturally important vectors of african trypanosomes. information on the molecular and biochemical nature of the tsetse/trypanosome interaction is lacking. here we describe three antimicrobial peptide genes, attacin, defensin, and diptericin, from tsetse fat body tissue obtained by subtractive cloning after immune stimulation with escherichia coli and trypanosomes. differential regulation of these genes shows the tsetse immune system can discriminate not on ...200111592981
[frequency of aedes aegypti and aedes albopictus larvae and pupae in traps, brazil].to evaluate the monthly frequency of larvae and pupae of aedes albopictus, aedes aegypti and other mosquitoe species in tires, and the influence of environmental factors on that.200111600929
dengue virus and insecticide susceptibility status of aedes aegypti mosquitoes from belagola village, mandya district, karnataka state: during and post-epidemic investigations.aedes aegypti mosquitoes collected during and after dengue virus epidemic season were exposed to diagnostic dosages of insecticides. mosquitoes collected during the epidemic showed resistance to ddt only, while mosquitoes collected after the control measures showed tolerance to malathion and low resistance to ddt. since there was no indication of malathion resistance in the mosquitoes collected during the epidemic, the second batch was subjected to malathion selection pressure for 8 generations ...200011668935
transcriptional regulation of the mosquito vitellogenin gene via a blood meal-triggered anautogenous mosquitoes, a blood meal is required for activation of genes encoding yolk protein precursors (ypp). vitellogenin (vg), the major ypp gene, is transcribed at a very high level following blood meal activation. it is expressed exclusively in the female fat body, the tissue producing most of mosquito hemolymph and immune proteins. in this paper, we analyzed the upstream region of the aedes aegypti vg gene in order to identify regulatory elements responsible for its unique expression ...200111674997
[yellow fever epidemiology in brazil].we have carried out a meticulous time-space-analysis of the incidence of yellow fever in humans in brazil from 1954 to 1972 and especially from 1973 to 1999. this study has added to our knowledge of the epidemiology of yellow fever and enabled us to redefine epidemiological zones and determine their geographical limits. the endemic area is located within the amazon basin; here cases are scattered and generally limited in number. however, there are also "foci of endemic emergence" within this are ...200111681224
development and evaluation of serotype- and group-specific fluorogenic reverse transcriptase pcr (taqman) assays for dengue virus.five fluorogenic probe hydrolysis (taqman) reverse transcriptase pcr (rt-pcr) assays were developed for serotypes 1 to 4 and group-specific detection of dengue virus. serotype- and group-specific oligonucleotide primers and fluorogenic probes were designed against conserved regions of the dengue virus genome. the rt-pcr assay is a rapid single-tube method consisting of a 30-min rt step linked to a 45-cycle pcr at 95 and 60 degrees c that generates a fluorogenic signal in positive samples. assays ...200111682539
identification of entomopathogenic bacillus isolated from simulium (diptera, simuliidae) larvae and adults.entomopathogenic bacteria isolated from simulium larvae and adults from breeding sites in the states of são paulo and rio de janeiro, brazil, were identified as 18 strains of bacillus thuringiensis and one of b. sphaericus. most of these strains were serotyped according to their flagellar antigens. however, nine of the b. thuringiensis samples, could not be serotyped and were designated as "autoagglutinating"; they were also shown to be toxic in preliminary tests against aedes aegypti larvae. ad ...200111685272
use of a computer model to identify potential hotspots for dengue fever in new describe the areas of potential dengue fever risk in new zealand for present climatic conditions and projected scenarios of climate change.200111700749
interleukin-4 receptor-stat6 signaling in murine infections with a tissue-dwelling nematode parasite.interleukin-4 (il-4) has been shown to be crucial in parasite expulsion in several gastrointestinal nematode infection models. data from both epidemiological studies with humans and experimental infections in animals imply a critical role for the type ii helper response, dominated by il-4, in host protection. here we utilized inbred mice on two distinct backgrounds to document the involvement of il-4 in the clearance of a primary infection of brugia from the murine host. our data from infections ...200111705956
the availability of potential hosts as a determinant of feeding behaviours and malaria transmission by african mosquito populations.a simple model for the influence of host availability on vector bloodmeal choice is applied to estimate the relative availabilities of humans, cattle and other host populations to malaria vectors in african communities, using published human blood indices and ratios of cattle to humans. cattle were bitten < 0.01, 0.021 +/- 0.11, 1.61 +/- 0.16 and 1.61 +/- 0.46 times as often as humans by anopheles funestus, an. gambiae sensu stricto and an. arabiensis in segera, tanzania, and an. gambiae sensu l ...200111706651
recovery of infectious pariacoto virus from cdna clones and identification of susceptible cell lines.pariacoto virus (pav) is a nodavirus that was recently isolated in peru from the southern armyworm, spodoptera eridania. virus particles are non enveloped and about 30 nm in diameter and have t=3 icosahedral symmetry. the 3.0-a crystal structure shows that about 35% of the genomic rna is icosahedrally ordered, with the rna forming a dodecahedral cage of 25-nucleotide (nt) duplexes that underlie the inner surface of the capsid. the pav genome comprises two single-stranded, positive-sense rnas: rn ...200111711613
a live attenuated recombinant dengue-4 virus vaccine candidate with restricted capacity for dissemination in mosquitoes and lack of transmission from vaccinees to mosquitoes.2adelta30 is a live dengue-4 virus vaccine candidate with a 30-nucleotide deletion in its 3'-untranslated region. to assess the transmissibility of 2adelta30 by mosquitoes, we compared its in vivo replication in mosquitoes with that of its wild type den-4 parent. both the vaccine candidate and wild type virus were equally able to infect the mosquito toxorhynchites splendens after intrathoracic inoculation. relative to its wild type parent, 2adelta30 was slightly restricted in its ability to infe ...200111716092
population genetic structure and competence as a vector for dengue type 2 virus of aedes aegypti and aedes albopictus from madagascar.starch gel electrophoresis was used to assess the polymorphism of 7 isoenzymes in single mosquitoes (field-collected f0 or f1 generation) for aedes albopictus (8 strains) from northern madagascar. mosquitoes of the f2 generation (3 strains of aedes aegypti and 10 strains of ae. albopictus) were tested for oral susceptibility to dengue type 2 virus. aedes aegypti was less susceptible to viral infection than ae. albopictus. the genetic differentiation was less high between ae. albopictus populatio ...200111716103
expression, purification, characterization and clinical relevance of raed a 1--a 68-kda recombinant mosquito aedes aegypti salivary allergen.accurate diagnosis of mosquito allergy has been precluded by the difficulty of obtaining salivary allergens. in this study, we expressed, purified, characterized and investigated the clinical relevance of a recombinant aedes aegypti salivary allergen, raed a 1. two cdna segments were ligated together to form the full-length aed a 1 gene. raed a 1 was expressed using a baculovirus/insect cell system, and purified using a combination of anion-exchange and gel-filtration chromatography. the purifie ...200111717185
horizontal and vertical transmission of dengue virus type 2 in highly and lowly susceptible strains of aedes aegypti mosquitoes.isofemale lines of aedes aegypti mosquitoes highly and lowly susceptible to dengue type 2 (den-2) virus (den(h) and den(l), respectively) were established by oral feeding and individual rearing. the susceptibility at f13 generation was found to be 61% and 25% for the den(h) and den(l) line, respectively. the virus-infected mosquito females were allowed to probe on bovine albumin phosphate saline ph 7.2 (baps) through membrane feeders. the presence of virus in the probed baps was determined eithe ...200111719984
[simplifying the sampling method for evaluating the larval density of aedes aegypti in são paulo state, brazil].to suggest changes in the sampling procedures for estimating the larval density of aedes aegypti in the state of são paulo, brazil, by assessing the efficacy and level of complexity of the current procedures.200111723519
kinetics of dengue virus-specific serum immunoglobulin classes and subclasses correlate with clinical outcome of infection.the kinetics of dengue virus (den)-specific serum immunoglobulin classes (immunoglobulin m [igm] and iga) and subclasses (igg1 to igg4) were studied in patients suffering from dengue fever (df), dengue hemorrhagic fever (dhf), and dengue shock syndrome (dss). serum samples from non-den febrile patients were included as controls. igm, igg1, and igg3 serum antibodies were the predominant immunoglobulins throughout the course of illness in all three patient groups. in contrast, iga antibodies were ...200111724841
candidate odorant receptors from the malaria vector mosquito anopheles gambiae and evidence of down-regulation in response to blood feeding.olfaction plays a major role in host preference and blood feeding, integral behaviors for disease transmission by the malaria vector mosquito anopheles gambiae sensu stricto (henceforth a. gambiae). we have identified four genes encoding candidate odorant receptors from a. gambiae that are selectively expressed in olfactory organs, contain approximately seven transmembrane domains, and show significant similarity to several putative odorant receptors in drosophila melanogaster. furthermore, one ...200111724964
invasions by insect vectors of human disease.nonindigenous vectors that arrive, establish, and spread in new areas have fomented throughout recorded history epidemics of human diseases such as malaria, yellow fever, typhus, and plague. although some vagile vectors, such as adults of black flies, biting midges, and tsetse flies, have dispersed into new habitats by flight or wind, human-aided transport is responsible for the arrival and spread of most invasive vectors, such as anthropophilic fleas, lice, kissing bugs, and mosquitoes. from th ...200211729075
malathion resistance and prevalence of the malathion carboxylesterase mechanism in populations of mosquito vectors of disease in sri determine the levels of malathion resistance and prevalence of the malathion carboxylesterase mechanism among mosquitoes in sri lanka.200111731814
dengue fever in pregnancy: a case report.background: dengue, a mosquito-borne flavivirus infection, is endemic in southeast asia. currently, the incidence has been increasing among adults. case presentation: a 26-year-old thai woman, g1p0 31 weeks pregnancy, presented with epigastric pain for 1 day. she also had a high-grade fever for 4 days. the physical examination, complete blood counts as well as serology confirmed dengue fever. the patient was under conservative treatment despite severe thrombocytopenia. she was well at the 3rd da ...200111747474
identification of novel plasmodium gallinaceum zygote- and ookinete-expressed proteins as targets for blocking malaria transmission.the development of transmission-blocking vaccines is one approach to malaria control. to identify novel plasmodium zygote- and ookinete-secreted proteins as targets of blocking malaria transmission, monoclonal antibodies (mabs) were produced against parasite-secreted proteins found in plasmodium gallinaceum ookinete culture supernatants. four mabs-1a6, 2a5, 2b5, and 4b6-were identified that bound to p. gallinaceum zygotes and ookinetes in diverse patterns in terms of spatial localization on para ...200211748169
recent advances in insect olfaction, specifically regarding the morphology and sensory physiology of antennal sensilla of the female sphinx moth manduca sexta.the antennal flagellum of female manduca sexta bears eight sensillum types: two trichoid, two basiconic, one auriculate, two coeloconic, and one styliform complex sensilla. the first type of trichoid sensillum averages 34 microm in length and is innervated by two sensory cells. the second type averages 26 microm in length and is innervated by either one or three sensory cells. the first type of basiconic sensillum averages 22 microm in length, while the second type averages 15 microm in length. ...200111754510
cloning and characterization of the crystal protein-encoding gene of bacillus thuringiensis subsp. yunnanensis.molecular cloning and characterization of a novel cry gene, cry32aa, of bacillus thuringiensis subsp. yunnanensis was carried out. the cry32aa protein was predicted to have a molecular mass of 139.2 kda and was found to have an unusual 42-amino-acid-long tail at the c terminus. the cry32aa gene was localized on the 103-mda plasmid of the organism. bioassays showed no toxicity against several moths and mosquitoes. however, it exhibited weak toxicity against larvae of the diamondback moth, plutell ...200211772653
a comparative genomic analysis of two distant diptera, the fruit fly, drosophila melanogaster, and the malaria mosquito, anopheles gambiae.genome evolution entails changes in the dna sequence of genes and intergenic regions, changes in gene numbers, and also changes in gene order along the chromosomes. genes are reshuffled by chromosomal rearrangements such as deletions/insertions, inversions, translocations, and transpositions. here we report a comparative study of genome organization in the main african malaria vector, anopheles gambiae, relative to the recently determined sequence of the drosophila melanogaster genome. the ances ...200211779831
evaluation of the efficacy of lambda-cyhalothrin applied as ultra-low volume and thermal fog for emergency control of aedes aegypti in extended-duration formulation of lambda-cyhalothrin (demand cs) applied as either an ultra-low volume (ulv) or thermal fog spray from a new handheld sprayer (terrier) against aedes aegypti was evaluated in honduras. spray applications were made at the front door for 1 min or to each room for 15 sec, both for the ulv and thermal fog applications to houses in separate blocks for each treatment. the efficacy and duration of effectiveness of the spray was determined from sentinel caged mosquito m ...200111804457
platelet-activating-factor-hydrolyzing phospholipase c in the salivary glands and saliva of the mosquito culex quinquefasciatus.a phospholipase c activity specific for platelet-activating factor (paf), named paf phosphorylcholine hydrolase, was found in the salivary glands and saliva of the human-feeding mosquito culex quinquefasciatus. the enzymatic activity was demonstrated by inhibition of paf-induced platelet aggregation, and by identification of substrate consumption and production of diacyl glyceride by electrospray-ionisation mass spectrometry. the activity has a neutral optimal ph and an apparent molecular mass o ...200111807106
coexpression of chitinase and the cry11aa1 toxin genes in bacillus thuringiensis serovar the spore stage, a cloned chitinase gene was coexpressed with the regulatory gene p19 and the toxin gene cry11aa1 in the hosts bacillus thuringiensis serovar israelensis strains 4q2-72 and c4q2-72. the chitinase gene was derived from a high-chitinase producer, bacillus licheniformis tp-1. two transcriptional fusion plasmids between the p19 or p19-cry11aa1 genes and the promoterless chitinase gene were constructed. in transcription order, the p16-19chi construct contained the p19 gene together ...200111812119
educational campaign versus malathion spraying for the control of aedes aegypti in colima, evaluate the effect of an educational campaign for reducing the breeding places of aedes aegypti, the principal vector of dengue; and to compare its effects with the ones obtained by spraying of malathion at ultralow volume.200211812816
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