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identification and mapping of the promoter for the gene encoding the ferritin heavy-chain homologue of the yellow fever mosquito aedes aegypti.mosquitoes are responsible for the transmission of numerous human diseases. the recent development of transgenic mosquitoes provides a new tool to examine molecular interactions between insect vectors and the pathogens they transmit. one focus in generating transgenic mosquito lies on expressing anti-pathogenic proteins at primary sites of pathogenic invasions, specifically the mosquito gut. promoters that direct the expression of anti-pathogenic proteins in the mosquito gut are thus sought afte ...200312459200
novel cost-effective method of screening soils for the presence of mosquito-pathogenic bacilli.the aim was to simplify the cumbersome conventional process of isolating virulent bacilli, which involves isolating all bacilli strains from a source followed by screening for strains that are effective for bio-control of mosquito vectors.200212460424
[main breeding-containers for aedes aegypti and associated culicids, argentina].breeding containers for aedes (stegomyia) aegypti were identified in two cities of chaco province (northeast argentina): presidencia roque saenz peña and machagai. all water-retaining recipients found in house backyards capable to retain water were classified according to their type and size, counted and checked. aedes aegypti and culex quinquefasciatus were the most frequently collected species, being also found cx. maxi, cx. saltanensis and ochlerotatus scapularis. tires and car batteries repr ...200212471389
laboratory vector competence experiments with yellow fever virus and five south african mosquito species including aedes aegypti.three domestic and peridomestic mosquito species, selected because their prevalence, distribution and ecology favoured them as potential urban vectors of yellow fever (yf) in south africa, were submitted to numerous tests for infectivity [measured as dose needed to infect 50% of the mosquitoes (mid50)], mainly with a kenyan strain (bc7914) of the virus. use of a nigerian virus strain (tvp1617) did not significantly alter infectivity. after artificial infective blood meals with titres of 7.0-8.0 ...200212474475
[cytopathological effect of bacillus thuringiensis israelensis endotoxins on the intestines of aedes aegypti mosquito larvae].the dynamics of pathological changes in the intestine of aedes aegypti larvae under the influence of toxins cry11a and cry4b produced by bacillus thuringiensis israelensis was studied by means of electron microscope. most significant ultrastructure changes in the intestine of the second instar larvae were observed in the midgut. the cytoplasm of cells disintegrated, and elongated lacunae appeared. the number of microvilli decreased, or they disappeared in the result of destruction. the peritroph ...200212481602
geographic genetic variation in populations of the dengue virus vector aedes aegypti.isoenzyme variation was assessed in 79 mosquito samples of aedes aegypti, and susceptibility to a dengue 2 virus strain was evaluated in 83 samples. analysis of fst values, differentiation indexes, and geographic distances separating populations revealed that genetic differences between populations depended on the species' history of migration and colonization. three major clusters were identified: (1). the sylvan form, ae. ae. formosus, from west africa and some islands in the indian ocean; (2) ...200212486524
evaluation of the residual effect of temephos on aedes aegypti (diptera, culicidae) larvae in artificial containers in manaus, amazonas state, brazil.trial tests and container observations were conducted in households to verify the residual effect of temephos in manaus, amazonas state, brazil. three plastic buckets, three tin cans, and three tires filled with water from an artesian well and larvicide were used in the experiment, with twenty-five third-instar larvae, which remained exposed for 24h, followed by mortality readings. the same types of containers were selected from common households. collection and counts followed by chemical treat ...200212488878
cross-resistance to pyrethroid and organophosphorus insecticides induced by selection with temephos in aedes aegypti (diptera: culicidae) from cuba.a sample of aedes aegypti (l.) from santiago de cuba, cuba, with a high level of temephos resistance (19.58x at the 50% lethal concentration [lc50]), was subjected to temephos selection to evaluate the utility of this organophosphate insecticide for mosquito control. high resistance developed after six generations of selection (200.00x). little or no cross-resistance was observed to the organophosphates, malathion and fenitrothion, but high cross-resistance was observed for the pyrethroid deltam ...200212495187
identification and molecular characterization of a chitinase from the hard tick haemaphysalis longicornis.a cdna encoding tick chitinase was cloned from a cdna library of mrna from haemaphysalis longicornis eggs and designated as cht1 cdna. the cht1 cdna contains an open reading frame of 2790 bp that codes for 930 amino acid residues with a coding capacity of 104 kda. the deduced amino acid sequence shows a 31% amino acid homology to aedes aegypti chitinase and a multidomain structure containing one chitin binding peritrophin a domain and two glycosyl hydrolase family 18 chitin binding domains. the ...200312502707
molecular characterization of a hamster viscerotropic strain of yellow fever virus.a hamster viscerotropic strain of yellow fever (yf) virus has been derived after serial passage of strain asibi through hamsters. the parental asibi/hamster p0 virus causes a mild and transient viremia in hamsters with no outward, clinical signs of illness. in contrast, the viscerotropic asibi/hamster p7 virus causes a robust viremia, severe illness, and death in subadult hamsters. the genome of the hamster viscerotropic asibi/hamster p7 virus has been sequenced and compared with the parental no ...200312502861
a live, attenuated dengue virus type 1 vaccine candidate with a 30-nucleotide deletion in the 3' untranslated region is highly attenuated and immunogenic in monkeys.the delta30 deletion mutation, which was originally created in dengue virus type 4 (den4) by the removal of nucleotides 172 to 143 from the 3' untranslated region (3' utr), was introduced into a homologous region of wild-type (wt) dengue virus type 1 (den1). the resulting virus, rden1delta30, was attenuated in rhesus monkeys to a level similar to that of the rden4delta30 vaccine candidate. rden1delta30 was more attenuated in rhesus monkeys than the previously described vaccine candidate, rden1mu ...200312502885
completion of the sequence of the nuclear ribosomal dna subunit of simulium sanctipauli, with descriptions of the 18s, 28s genes and the igs.we describe the igs-ets, 18s and 28s ribosomal gene sequences of simulium sanctipauli vajime & dunbar, a member of the s. damnosum theobald (diptera: simuliidae) complex of blackflies (diptera: simuliidae). these regions, together with the its-1, its-2 and 5.8s rdna presented elsewhere (accession number u36206), constitute the composite sequence of the entire rdna unit, making s. sanctipauli the second dipteran species of medical importance for which the entire rdna has been sequenced. despite t ...200212510891
isoenzyme variation in aedes aegypti correlated with dirofilaria immitis infectability.from the vero beach strain of the mosquito aedes (stegomyia) aegypti (l.) (diptera: culicidae), substrains were selected for susceptibility (ss) and refractoriness (rr) to the dog heartworm dirofilaria immitis (leidy) (filarioidea: onchocercidae). these two lines and their reciprocal f1 hybrids were analysed for genetic variation at 14 enzyme loci, using polyacrylamide gel electrophoresis. six of the enzyme loci showed variation (sample size 48 alleles/locus/line). three of these were monomorphi ...200212510895
isoenzyme differentiation of aedes aegypti populations in french guiana.population genetics of peri-domestic aedes aegypti (diptera: culicidae), vector of dengue and yellow fever, were investigated by gel electrophoresis of 10 enzyme loci in 14 samples of mosquito larvae collected in 1997-1998 from localities separated by distances of 3-275 km in french guiana. genetic differentiation between geographical populations was generally high (mean fst = +0.111, p < 10(-5)) even among seven sites <30 km apart (fst = +0.137, p < 0.05), but not positively correlated with dis ...200212510901
host-specific cues cause differential attractiveness of kenyan men to the african malaria vector anopheles gambiae.many studies have suggested that variability in the attractiveness of humans to host-seeking mosquitoes is caused by differences in the make-up of body emanations, and olfactory signals in particular. most investigations have either been laboratory-based, utilising odour obtained from sections of the body, or have been done in the field with sampling methods that do not discriminate between visual, physical and chemical cues of the host. accordingly, evidence for differential attractiveness base ...200212513703
[an etiological and serological study on dengue epidemic in guangdong province].in 1978-1995, dengue fever epidemics(serotype 1-4) occurred in guangdong province. among 9 species of mosquitoes found in the epidemic areas, the positive rate of virus isolation in aedes albopictus was 20.69%, in aedes aegypti 18.95%, in culex quinquefasciatus 10.29%, dengue viruses were not isolated in other 6 species of mosquitoes. the positive rate of virus isolation in the three species showed no significant differences (chi 2 = 2.77 p > 0.05). aedes aegypti was the main transmitting vector ...199812515199
cloning and characterization of a cytolytic and mosquito larvicidal delta-endotoxin from bacillus thuringiensis subsp. darmstadiensis.the cytolytic delta-endotoxin gene from bacillus thuringiensis subsp. darmstadiensis was amplified from genomic dna by pcr by using primers designed from the sequence of cyt2aa1 gene of b. thuringiensis subsp. kyushuensis. dna sequence analysis revealed an open reading frame translating to a 259-amino acid sequence. the cloned gene was designated cyt2aa2. this gene was highly expressed in escherichia coli as inclusion bodies that could be solubilized in 50 m m na(2)co(3), ph 10.5. activation of ...200312520362
cyclicity of mosquito vitellogenic ecdysteroid-mediated signaling is modulated by alternative dimerization of the rxr homologue ultraspiracle.in anautogenous mosquitoes, egg maturation requires a blood meal. as a consequence, mosquitoes are vectors of numerous devastating human diseases. blood feeding triggers a 20-hydroxyecdysone (20e) hormonal cascade, which activates yolk protein precursor (ypp) genes in the female fat body, an insect metabolic tissue. an important adaptation for anautogeny is the previtellogenic arrest preventing activation of ypp genes. equally essential is termination of their expression, so that another arrest ...200312522263
[detection of dengue virus genome rna in some kinds of animals caught from dengue fever endemic areas in hainan island with reverse transcription-polymerase chain reaction].detection of dengue virus genome rna in brain of bats caught from dengue fever endemic areas in hainan island were carried out with reverse transcription-polymerase chain reaction(rt-pcr). positive result was demonstrated in 20 of 35 bats tested, with a positive rate of 57.14%; rt-pcr was applied for the detection of dengue virus genome rna in sera of bats caught from the endemic areas in hainan island, 3(16.66%) of 18 sera were positive. dengue virus genome rna in female aedes aegypti captured ...199812526321
texas lifestyle limits transmission of dengue virus.urban dengue is common in most countries of the americas, but has been rare in the united states for more than half a century. in 1999 we investigated an outbreak of the disease that affected nuevo laredo, tamaulipas, mexico, and laredo, texas, united states, contiguous cities that straddle the international border. the incidence of recent cases, indicated by immunoglobulin m antibody serosurvey, was higher in nuevo laredo, although the vector, aedes aegypti, was more abundant in laredo. environ ...200312533286
cloning and characterization of trypsin- and chymotrypsin-like proteases from the midgut of the sand fly vector phlebotomus papatasi.trypsin and chymotrypsin serine proteases are the main digestive proteases in diptera midguts and are also involved in many aspects of the vector-parasite relationship. in sand flies, these proteases have been shown to be a potential barrier to leishmania growth and development within the midgut. here we describe the sequence and partial characterization of six phlebotomus papatasi midgut serine proteases: two chymotrypsin-like (ppchym1 and ppchym2) and four trypsin-like (pptryp1-pptryp4). all s ...200312535675
a hat trick--plasmodium, anopheles and homo.the genomes of the malaria parasite, its vector and its host are now sequenced. this has been a tremendous scientific achievement. but will it offer hope to the millions who die from malaria each year? yes, but only if combined with political will and social change.200312537542
evaluation of polymer-based granular formulations of bacillus thuringiensis israelensis against larval aedes aegypti in the laboratory.a strategy to increase residual activity of bacillus thuringiensis serovar. israelensis (bti) extract through slow-release formulations and protection from solar radiation was studied. the median lethal concentration (lc50) and 90% lethal concentration (lc90) levels of laboratory-reared early 4th-stage larval aedes aegypti after exposure to bti extract were determined. formulations with 4 polymers and 1 solar protectant were prepared, and their shelf lives were evaluated for year-long storage at ...200212542194
isolation and expression of a sterol carrier protein-2 gene from the yellow fever mosquito, aedes aegypti.trafficking of cholesterol in insects is a very important process due to the fact that insects depend on dietary cholesterol to fulfil their physiological needs. we identified a putative mosquito sterol carrier protein-2 (scp-2) cdna from fourth instar subtracted cdna library. the aescp-2 protein has high degree homology in the sterol transfer domain to both rat and human scp-2. transcripts of aescp-2 in fourth instars were detected strongly in the midgut, and weakly in the head and hindgut. in ...200312542635
laboratory evaluation of vectobac as against aedes aegypti in monterrey, nuevo león, mexico.intensive use of the organophosphate insecticide malathion against adults and temephos against larvae of aedes aegypti in mexico over the past 30 years has led to problems requiring the use of new larvicides. toward this objective, bacillus thuringiensis var. israelensis (bti), a target-specific and environmentally safer control agent, was evaluated. laboratory bioassays were done to determine the susceptibility of 2nd- and 3rd-stage larvae of ae. aegypti to vectobac 12 as (aqueous suspension, 6 ...200212545970
fast and slow blood-feeding durations of aedes aegypti mosquitoes in trinidad.the duration of blood feeding by similar-sized aedes aegypti (l.) was determined under laboratory conditions in trinidad, west indies. ae. aegypti from the f0 generation contained individuals that fed quickly (106.2 seconds) as well as slowly (330.0 seconds). among the fast feeders (<2 min), the time taken for blood feeding during the first gonotrophic cycle was much shorter than that observed for the 2nd, 3rd and 4th gonotrophic cycles. in contrast, among the slow feeders the time taken was muc ...200212546453
isolation of a pseudomonas fluorescens metabolite/exotoxin active against both larvae and pupae of vector mosquitoes.a formulation was developed from the metabolite(s) of a novel pseudomonas fluorescens migula strain (vcrc b426) and tested against 4th-instar larvae and pupae of three species of vector mosquitoes, anopheles stephensi liston, culex quinquefasciatus say and aedes aegypti (l). the larvae and pupae of an. stephensi were the most susceptible to the formulation, followed by those of c. quinquefasciatus and ae. aegypti, in that order, and the dosage requirement for pupal mortality was less than that r ...200312558096
recombinant strain of bacillus thuringiensis producing cyt1a, cry11b, and the bacillus sphaericus binary toxin.a novel recombinant bacillus thuringiensis subsp. israelensis strain that produces the b. sphaericus binary toxin, cyt1aa, and cry11ba is described. the toxicity of this strain (50% lethal concentration [lc(50)] = 1.7 ng/ml) against fourth-instar culex quinquefasciatus was higher than that of b. thuringiensis subsp. israelensis ips-82 (lc(50) = 7.9 ng/ml) or b. sphaericus 2362 (lc(50) = 12.6 ng/ml).200312571069
meliternatin: a feeding deterrent and larvicidal polyoxygenated flavone from melicope subunifoliolata.we screened more than 60 malaysian plants against two species of insects and found that melicope subunifoliolata (stapf) t.g. hartley (rutaceae) showed strong feeding deterrent activity against sitophilus zeamais motsch. (curculionidae) and very good larvicidal activity against aedes aegypti l. (diptera). one anti-insect compound, meliternatin (3,5-dimethoxy-3',4',6,7-bismethylendioxyflavone) (6) and six other minor polyoxygenated flavones were isolated from m. subunifoliolata.200312591266
relish-mediated immune deficiency in the transgenic mosquito aedes aegypti.the lack of genetic means has been a serious limitation in studying mosquito immunity. we generated relish-mediated immune deficiency (rmid) by transforming aedes aegypti with the delta rel transgene driven by the vitellogenin (vg) promoter using the pbac[3xp3-egfp, afm] vector. a stable transformed line had a single copy of the vg-delta rel transgene. the vg-delta rel transgene expression was highly activated by blood feeding, and transgenic mosquitoes were extremely susceptible to the infectio ...200312594340
vector competence of australian mosquitoes (diptera: culicidae) for japanese encephalitis virus.australian mosquitoes were evaluated for their ability to become infected with and transmit a torres strait strain of japanese encephalitis virus. mosquitoes, which were obtained from either laboratory colonies and collected using centers for disease control and prevention light traps baited with co2 and octenol or reared from larvae, were infected by feeding on a blood/sucrose solution containing 10(4.5 +/- 0.1) porcine stable-equine kidney (ps-ek) tissue culture infectious dose50/mosquito of t ...200312597658
antifungal, antioxidant and larvicidal activities of compounds isolated from the heartwood of mansonia gagei.eleven compounds isolated from the heartwood of mansonia gagei were tested for their antifungal activities against cladosporium cucumerinum and candida albicans, as well as for their larvicidal activities against aedes aegypti and radical scavenging properties in a dpph assay. mansonone c (4) was found to be the most interesting compound with antifungal activities against cladosporium cucumerinum and candida albicans as well as for its larvicidal properties against aedes aegypti. mansonone e (5) ...200312601687
determination of 'irritant' threshold concentrations for intradermal testing with allergenic insect extracts in normal horses.sixteen healthy horses with no history of skin or respiratory disease were used for an intradermal testing (idt) threshold study, in order to determine the concentrations of 13 commercial allergenic insect extracts most appropriate for idt. five dilutions of each extract were used, which included the manufacturer's recommended concentrations for equine idt, plus one dilution higher and three lower than these standard concentrations. allergens tested included caddisfly (trichoptera spp.), mayfly ...200312603683
sex-specific and blood meal-induced proteins of anopheles gambiae midguts: analysis by two-dimensional gel electrophoresis.anopheles gambiae is the main vector of plasmodium falciparum in africa. the mosquito midgut constitutes a barrier that the parasite must cross if it is to develop and be transmitted. despite the central role of the mosquito midgut in the host/parasite interaction, little is known about its protein composition. characterisation of an. gambiae midgut proteins may identify the proteins that render an. gambiae receptive to the malaria parasite.200312605724
a potential role for phenylalanine hydroxylase in mosquito immune responses.in mosquitoes the melanotic encapsulation immune response is an important resistance mechanism against filarial worms and malaria parasites. the rate limiting substrate for melanin production is tyrosine that is hydroxylated by phenoloxidase (po) to produce 3, 4-dihydroxyphenylalanine. the single pathway for endogenous production of tyrosine is by hydroxylation of phenylalanine by phenylalanine hydroxylase (pah). in this study we describe a potential role for pah in melanotic immune responses in ...200312609519
beenomes to bombyx: future directions in applied insect genomics.the recent sequencing of the anopheles gambiae genome showcases the genetic breadth of insects and a trend towards sequencing organisms directly involved with human welfare. we describe traits in other insect species that make them important candidates for genomics projects, and review several recent workshops aimed at uniting researchers working with insect species to efficiently address problems in medicine, biotechnology, and agriculture.200312620096
vector competence of brazilian aedes aegypti and ae. albopictus for a brazilian yellow fever virus isolate.because the potential urban yellow fever (yf) mosquito vectors aedes aegypti and ae. albopictus are at historical highs in brazil, both in terms of density and geographical range, we assessed the risk of an urban yf epidemic in brazil. we evaluated and confirmed in a laboratory setting the vector competence of brazilian ae. aegypti for a currently circulating strain of yf virus, and investigated the potential for brazilian ae. albopictus to transmit yf.200212625133
control of the aedes vectors of the dengue viruses and wuchereria bancrofti: the french polynesian experience.in most of the 130 islands of french polynesia, the stenotopic mosquitoes aedes aegypti (the main local vector for the viruses causing dengue) and aedes polynesiensis (the main local vector of wuchereria bancrofti) share many breeding sites in water containers such as discarded cans, coconut shells, buckets and water-storage pots and drums. in addition to selective application of insecticides, non-polluting methods of controlling these mosquitoes have been evaluated during the last decade in two ...200212625924
american genotype structures decrease dengue virus output from human monocytes and dendritic cells.the dengue virus type 2 structures probably involved in human virulence were previously defined by sequencing the complete genome of both american and southeast (se) asian genotype templates in patient serum (k. c. leitmeyer et al., j. virol. 73:4738-4747, 1999). we have now evaluated the effects of introducing a mutation in the envelope glycoprotein (e) gene and/or replacement of 5'- and 3'-nontranslated regions on dengue virus replication in human primary cell cultures. a series of chimeric in ...200312634353
diverse dengue type 2 virus populations contain recombinant and both parental viruses in a single mosquito host.envelope (e) protein genes sampled from populations of dengue 2 (den-2) virus in individual aedes aegypti mosquitoes and in serum from dengue patients were copied to cdna, cloned, and sequenced. the nucleotide sequences of the e genes in more than 70% of the clones differed from the consensus sequence for the corresponding virus population at up to 11 sites, and 24 of the 94 clones contained at least one stop codon. virus populations recovered up to 2 years apart yielded clones with similar poly ...200312634407
observations on the swarming and mating behaviour of anopheles funestus from southern mozambique.control of malaria by the release of genetically modified mosquitoes refractory to transmission is now becoming a possibility. in many areas of africa, anopheles gambiae is found together with an equally important vector, an. funestus. given their sympatry and the likelihood of a similar mating period some aspects of the mating behaviour of an. gambiae s.l. and an. funestus are likely to differ. we therefore attempted to characterise the swarming behaviour of an. funestus and to determine if any ...200312636875
low oral receptivity for dengue type 2 viruses of aedes albopictus from southeast asia compared with that of aedes aegypti.dengue hemorrhagic fever has been a major health problem in asia since the 1950s. during this period, the former principal vector of dengue viruses in asia, aedes albopictus, was replaced by aedes aegypti in most major cities of the area. ae. aegypti is now considered the main vector of dengue viruses in asia. surprisingly, however, this mosquito has been described as having a relatively low oral receptivity for dengue viruses compared with ae. albopictus. in the present study, we compared the r ...200312641412
dengue and its vectors in thailand: calculated transmission risk from total pupal counts of aedes aegypti and association of wing-length measurements with aspects of the larval habitat.working in a village dengue focus in chachoengsao province, thailand, aedine mosquito larvae and pupae were counted in all containers of 10 houses per month. the wings of female aedes aegypti (l.) emerging from pupae were measured. number of pupae and size of emerging females increased in containers with qualities that favored availability of larval food sources (e.g., uncovered containers). the small size of most mosquitoes compared with those raised in the laboratory indicated that the larval ...200312641413
amplification of the sylvatic cycle of dengue virus type 2, senegal, 1999-2000: entomologic findings and epidemiologic considerations.after 8 years of silence, dengue virus serotype 2 (denv-2) reemerged in southeastern senegal in 1999. sixty-four denv-2 strains were isolated in 1999 and 9 strains in 2000 from mosquitoes captured in the forest gallery and surrounding villages. isolates were obtained from previously described vectors, aedes furcifer, ae. taylori, ae. luteocephalus, and--for the first time in senegal--from ae. aegypti and ae. vittatus. a retrospective analysis of sylvatic denv-2 outbreaks in senegal during the la ...200312643833
isolation and properties of floral defensins from ornamental tobacco and petunia.the flowers of the solanaceous plants ornamental tobacco (nicotiana alata) and petunia (petunia hybrida) produce high levels of defensins during the early stages of development. in contrast to the well-described seed defensins, these floral defensins are produced as precursors with c-terminal prodomains of 27 to 33 amino acids in addition to a typical secretion signal peptide and central defensin domain of 47 or 49 amino acids. defensins isolated from n. alata and petunia flowers lack the c-term ...200312644678
development of an orally infectious sindbis virus transducing system that efficiently disseminates and expresses green fluorescent protein in aedes aegypti.we have constructed an orally infectious sindbis virus, me2/5'2j/gfp, that expresses green fluorescent protein (gfp) in the midgut of aedes aegypti and in other tissues as the virus disseminates. this virus has two unique features that are improvements over the sin-based expression systems currently used in mosquitoes. first, a subgenomic rna promoter and gfp coding sequence is located 5'- to the second subgenomic promoter and structural genes of the virus. second, the e2 glycoprotein gene of te ...200312653932
a model of dengue fever.dengue is a disease which is now endemic in more than 100 countries of africa, america, asia and the western pacific. it is transmitted to the man by mosquitoes (aedes) and exists in two forms: dengue fever and dengue haemorrhagic fever. the disease can be contracted by one of the four different viruses. moreover, immunity is acquired only to the serotype contracted and a contact with a second serotype becomes more dangerous.200312657162
rapid phagocytosis and melanization of bacteria and plasmodium sporozoites by hemocytes of the mosquito aedes aegypti.mosquitoes are vectors of many deadly and debilitating pathogens. in the current study, we used light and electron microscopies to study the immune response of aedes aegypti hemocytes to bacterial inoculations, plasmodium gallinaceum natural infections, and latex bead injections. after challenge, mosquitoes mounted strong phagocytic and melanization responses. granulocytes phagocytosed bacteria singly or pooled them inside large membrane-delimited vesicles. phagocytosis of bacteria, plasmodium s ...200312659304
[aedes aegypti, vector of the dengue virus: spatio-temporal structure of its genetic variation].aedes aegypti is the main vector of dengue viruses. methods for limiting the spread of dengue outbreaks are currently based on vector control. estimates of population genetic organization and gene flow with respect to vector capacity have provided great insights into dengue epidemiology. in vietnam, dengue hemorrhagic fever was detected in the 1950's and becomes today the major problem of public health. among factors influencing dengue epidemiology, ecological disturbances have a direct impact o ...200212669664
spatial distribution of the larval indices of aedes aegypti in guadalupe, nuevo león, mexico, with circular distribution analysis.a census of all outdoor larval breeding sites (951) present in 361 dwellings in a neighborhood of guadalupe in northeastern mexico was conducted in october 1997 to determine larval indices of aedes aegypti, and their relationship to human population density and vegetation type. here we present a method that allows finding the direction and extrapolar flight range of vectors, as parameters in the dynamics of dengue transmission. by using circular statistics applied to each block of data, ranges ( ...200312674529
field evaluation of a smoke-generating formulation containing beta-cypermethrin against the dengue vector in argentina.previous results from laboratory and prefield assays obtained by our laboratory indicated that the fumigant canister cipein pf-7 (bolate) a smoke-generating formulation containing 5% beta-cypermethrin, has excellent performance as an adulticide for aedes aegypti control. a field trial was carried out to evaluate the effectiveness of cipein pf-7 to control adult mosquitoes of ae. aegypti inside houses. the trial was carried out in colonia delicia, a locality of 4,750 inhabitants, located in misio ...200312674535
evaluation of the efficacy of lambda-cyhalothrin applied by three spray application methods for emergency control of aedes aegypti in costa rica.an extended duration formulation of lambda-cyhalothrin (icon cs) applied as either an ultra-low volume (ulv) or thermal fog spray from a new hand-held sprayer (twin-fog) or as a low-volume spray (lv) from a backpack mist blower against aedes aegypti was evaluated in costa rica. spray applications were made at the front door for 1 min or to each room for 15 sec for the ulv and lv, and thermal fog applications were made to houses in separate blocks for each treatment. the efficacy and duration of ...200312674536
detection of lysozyme-like enzymatic activity secreted by an immune-responsive mosquito cell line.using molecular approaches, we have recently shown that the c7-10 mosquito cell line from aedes albopictus, and the aag-2 line from aedes aegypti, secrete a variety of immune peptides into the culture medium, including cecropins, defensins, transferrin, and lysozyme. the diversity of these peptides makes it difficult to quantify the relative activities of each molecule, because possible synergistic interactions may occur. using a microtiter plate assay with live bacteria, we now show that c7-10 ...200312676552
differential susceptibility of aedes aegypti to infection by the american and southeast asian genotypes of dengue type 2 virus.outbreaks of dengue hemorrhagic fever have coincided with the introduction of the southeast (se) asian genotype of dengue type 2 virus in the western hemisphere. this introduced genotype appears to be rapidly displacing the indigenous, american genotype of dengue 2 virus throughout the region. these field observations raise the possibility that the se asian genotype of dengue 2 is better adapted for vector transmission than its american counterpart. to evaluate this hypothesis, we compared the a ...200112680353
persistent transovarial infection of successive generations of aedes aegypti mosquitoes with dengue-3 virus. 200312685627
resistance of aedes aegypti to organophosphates in several municipalities in the state of rio de janeiro and espírito santo, brazil.chemical insecticides have been widely used in brazil for several years. this exposes mosquito populations to an intense selection pressure for resistance to insecticides. in 1999, the brazilian national health foundation started the first program designed to monitor the resistance of aedes aegypti to insecticides. we analyzed populations from 10 municipalities (from 84 selected in brazil) in the states of rio de janeiro and espírito santo. exposure of larvae to a diagnostic dose of temephos sho ...200312685640
[a challenge for the public health system in brazil: dengue control].this article presents a critical analysis of the traditional strategy used to control aedes aegypti using "health surveillance patrols", with periodic visits to all urban buildings. the strategy is not viable and/or is administratively unfeasible at present, since it has been proposed since the 1980s but has not been implemented. brazilian health reform prioritized the expansion of coverage for basic health services, and not measures to control specific diseases. a. aegypti, which was reintroduc ...200312700811
mice genetically deficient in immunoglobulin e are more permissive hosts than wild-type mice to a primary, but not secondary, infection with the filarial nematode brugia malayi.primary and secondary murine and human infections with brugia malayi are characterized by substantial increases in levels of immunoglobulin e (ige). to investigate whether this is necessary for worm clearance, ige(-/-) mice were subjected to primary- and secondary-infection protocols. following a primary infection, ige(-/-) mice displayed a profound deficit in their ability to clear an intraperitoneal injection of l3 infective-stage larvae in comparison to wild-type counterparts and maintained s ...200312704117
breeding habitats and larval indices of aedes aegypti (l) in residential areas of rajahmundry town, andhra pradesh.entomological studies on relative prevalence and distribution of adults and immatures of aedes aegypti were conducted in rajahmundry town of andhra pradesh from december 1998 to november 1999. adults and immature stages of aedes aegypti were found in all the 22 localities viz; posh area (8), mixed area (8) and slum area (6) of the town. larval indices were found to be higher in slum areas as compared to mixed or posh areas of the town. however, the larval habitats were observed to be similar in ...200212718342
specific mutations within the alpha4-alpha5 loop of the bacillus thuringiensis cry4b toxin reveal a crucial role for asn-166 and tyr-170.the widely accepted model for toxicity mechanisms of the bacillus thuringiensis cry delta-endotoxins suggests that helices alpha4 and alpha5 form a helix-loop-helix hairpin structure to initiate membrane insertion and pore formation. in this report, alanine substitutions of two polar amino acids (asn-166 and tyr-170) and one charged residue (glu-171) within the alpha4-alpha5 loop of the 130-kda cry4b mosquito-larvicidal protein were initially made via polymerase chain reaction-based directed mut ...200312721492
synthetic propeptide inhibits mosquito midgut chitinase and blocks sporogonic development of malaria parasite.incessant transmission of the parasite by mosquitoes makes most attempts to control malaria fail. blocking of parasite transmission by mosquitoes therefore is a rational strategy to combat the disease. upon ingestion of blood meal mosquitoes secrete chitinase into the midgut. this mosquito chitinase is a zymogen which is activated by the removal of a propeptide from the n-terminal. since the midgut peritrophic matrix acts as a physical barrier, the activated chitinase is likely to contribute to ...200312727225
characterization of flagellar antigens and insecticidal activities of bacillus thuringiensis populations in animal feces.in total, 287 bacillus thuringiensis isolates, recovered from feces of 28 zoo-maintained animal species, were examined for flagellar (h) antigenicity and insecticidal activity. serologically, 209 isolates (72.8%) were allocated to the 8 h serogroups, 4 were untypable, and 74 were untestable. among the 8 h serotypes detected, h3abc (serovar kurstaki) predominated at a high frequency of 88.0%, followed by h6 (serovar entomocidus) with a frequency of 7.7%. insecticidal activity was associated with ...200312732979
bacillus thuringiensis associated with faeces of the kerama-jika, cervus nippon keramae, a wild deer indigenous to the ryukyus, japan.faeces of the kerama-jika (cervus nippon keramae), a wild shika deer indigenous to the ryukyus, japan, were examined for the natural occurrence of bacillus thuringiensis. of the ten faecal samples tested, seven contained this organism. the frequency of b. thuringiensis was 8.5% among 387 colonies of spore-forming bacteria belonging to the bacillus cereus/b. thuringiensis group. of 33 b. thuringiensis isolates recovered, only one isolate, assigned to the serotype h3abc (serovar kurstaki), exhibit ...200312746858
molecular analysis of the serine/threonine kinase akt and its expression in the mosquito aedes aegypti.a key component of the insulin-signalling pathway, the protein kinase akt, was identified and cloned as a cdna from ovaries of the mosquito aedes aegypti. an ortholog gene was found in the anopheles gambiae genome database, and like other akts, both mosquito akts possess pleckstrin homology domains for membrane binding and a serine/threonine kinase domain. when ae. aegypti ovaries were treated with bovine insulin in vitro, a putative akt was threonine-phosphorylated, as expected for akts. aaegak ...200312752655
analysis of genetic relatedness between populations of aedes aegypti from different geographic regions of são paulo state, brazil.rapd markers have been used for the analysis of genetic differentiation of aedes aegypti, because they allow the study of genetic relationships among populations. the aim of this study was to identify populations in different geographic regions of the s o paulo state in order to understand the infestation pattern of a. aegypti. the dendrogram constructed with the combined data set of the rapd patterns showed that the mosquitoes were segregated into two major clusters. mosquitoes from the western ...200312754576
isolation of a new flavivirus related to cell fusing agent virus (cfav) from field-collected flood-water aedes mosquitoes sampled from a dambo in central kenya.cell fusing agent virus (cfav) is an rna insect virus that was isolated from a line of aedes aegypti mosquito cells and has been assigned to the family flaviviridae, genus flavivirus. we report here the first isolation of a cfa-like virus from field-collected mosquitoes. mosquito larvae and pupae were sampled from flooded dambos in central province, kenya during the short rain season of 1999. specimens were reared to adults, identified and pooled by species and were tested for the presence of vi ...200312756616
t cells are required for host protection against brugia malayi but need not produce or respond to interleukin-4.t cells are known to be required for host protection in mouse models of brugia malayi infection. several independent studies in murine models have also highlighted the rapid induction of th2-like responses after infection with b. malayi or b. pahangi. previous data from our laboratory have described a significant increase in permissiveness in the absence of interleukin-4 (il-4), the "prototypical" th2 cytokine, involved in both the induction and maintenance of th2 responses. these observations l ...200312761087
dispersal of aedes aegypti and aedes albopictus (diptera: culicidae) in an urban endemic dengue area in the state of rio de janeiro, brazil.experimental releases of female aedes (stegomyia) aegypti and aedes (stegomyia) albopictus were performed in august and september 1999, in an urban area of nova igua u, state of rio de janeiro, brazil, to estimate their flight range in a circular area of 1,600 m where 1,472 ovitraps were set. releases of 3,055 ae. aegypti and 2,225 ae. albopictus females, fed with rubidium (rb)-marked blood and surgically prevented from subsequent blood-feeding, were separated by 11 days. rb was detected in ovit ...200312764433
ovarian development induced in decapitated female culex pipiens pallens mosquitoes by infusion of physiological quantities of 20-hydroxyecdysone together with amino acids.infusion of 20-hydroxyecdysone into the hemocoel of unfed decapitated female culex pipiens pallens mosquitoes, at a very low rate of 500-2000pg per day, often stimulated oögenesis of this species, when the hormone was infused together with amino acids. the hormone alone or amino acids alone showed no such stimulatory effect. previous reports that using an abdomen ligated immediately after a blood meal for hormone injection reduced the quantity of 20-hydroxyecdysone needed to activate unfed femal ...199812770172
larval growth and biosynthesis of reserves in mosquitoes.developmental instars of four species of mosquitoes have been analyzed for growth and synthesis of biomass with respect to their caloric content of protein, lipids, and carbohydrates for each instar of aedes aegypti and culex pipiens of the subfamily culicinae, and anopheles albimanus, and an. gambiae of the subfamily anophelinae. the diameter of the thorax grows during the intermolt, reflecting continuous increase in biomass because it correlates significantly with the larval synthesis of total ...199912770329
natriuretic and depolarizing effects of a stable fly (stomoxys calcitrans) factor on malpighian tubules.a two-step hplc purification procedure resulted in a factor from the stable fly that depolarizes the lumen-negative transepithelial voltage (v(t)) of the adult stable fly malpighian tubule. when applied to tubules of the female mosquito, aedes aegypti, this factor partially mimics the electrophysiological actions of the mosquito natriuretic factor (mnf). it also selectively increases active transepithelial na transport by the mosquito malpighian tubule. the blood meal causes a transient increase ...199712770470
the v-type h(+)-atpase in malpighian tubules of aedes aegypti: localization and activity.the v-type h(+)-atpase is thought to provide the driving force for transepithelial electrolyte and fluid secretion in malpighian tubules. to confirm the presence of this proton pump in malpighian tubules of the yellow fever mosquito aedes aegypti, we used several antibodies raised against the v-type h(+)-atpase of manduca sexta. western blot analysis confirmed the presence of the v-type h(+)-atpase in malpighian tubules of aedes aegypti. in situ immunostaining identified the v-type h(+)-atpase a ...200312771170
functional characterization of a glutamate/aspartate transporter from the mosquito aedes aegypti.glutamate elicits a variety of effects in insects, including inhibitory and excitatory signals at both neuromuscular junctions and brain. insect glutamatergic neurotransmission has been studied in great depth especially from the standpoint of the receptor-mediated effects, but the molecular mechanisms involved in the termination of the numerous glutamatergic signals have only recently begun to receive attention. in vertebrates, glutamatergic signals are terminated by na(+)/k(+)-dependent high-af ...200312771173
laboratory surveillance of dengue in argentina, 1995-2001.local transmission of dengue fever virus in argentina is increased by the presence of aedes aegypti mosquitoes and dengue outbreaks in neighboring countries. from 1995 to 2001, a laboratory-based active surveillance program detected 922 dengue cases. indigenous transmission involving dengue-1 and -2 serotypes was confirmed only in subtropical areas in northern argentina.200312781019
dendritic-cell-specific icam3-grabbing non-integrin is essential for the productive infection of human dendritic cells by mosquito-cell-derived dengue viruses.dengue virus (dv) is a mosquito-borne flavivirus that causes haemorrhagic fever in humans. dv primarily targets immature dendritic cells (dcs) after a bite by an infected mosquito vector. here, we analysed the interactions between dv and human-monocyte-derived dcs at the level of virus entry. we show that the dc-specific icam3-grabbing non-integrin (dc-sign) molecule, a cell-surface, mannose-specific, c-type lectin, binds mosquito-cell-derived dvs and allows viral replication. conclusive evidenc ...200312783086
ex vivo cytotoxicity of the bacillus thuringiensis cry4b delta-endotoxin to isolated midguts of aedes aegypti larvae.the pathological effect of the bacillus thuringiensis cry delta- endotoxins on susceptible insect larvae had extensive damage on the midgut epithelial cells. in this study, an ex vivo assay was devised for assessing the insecticidal potency of the cloned cry4b mosquito-larvicidal protein that is expressed in escherichia coli. determination of toxicity was carried out by using a cell viability assay on the midguts that were dissected from 5-day old aedes aegypti mosquito larvae. after incubation ...200312787485
dynamics of molecular markers linked to the resistance loci in a mosquito-plasmodium system.models on the evolution of resistance to parasitism generally assume fitness tradeoffs between the costs of being parasitized and the costs associated with resistance. this study tested this assumption using the yellow fever mosquito aedes aegypti and malaria parasite plasmodium gallinaceum system. experimental mosquito populations were created by mixing susceptible and resistant strains in equal proportions, and then the dynamics of markers linked to loci for plasmodium resistance and other unl ...200312807772
efficiency of dengue serotype 2 virus strains to infect and disseminate in aedes aegypti.dengue serotype 2 (den-2) viruses with the potential to cause dengue hemorrhagic fever have been shown to belong to the southeast (se) asian genotype. these viruses appear to be rapidly displacing the american genotype of den-2 in the western hemisphere. to determine whether distinct genotypes of den-2 virus are better adapted to mosquito transmission, we classified 15 viral strains of den-2 phylogenetically and compared their ability to infect and disseminate in different populations of aedes a ...200312812340
thioredoxin from brugia malayi: defining a 16-kilodalton class of thioredoxins from nematodes.thioredoxins are a family of small redox proteins that undergo nadph-dependent reduction by thioredoxin reductase. this results in a supply of reducing equivalents that cells use in a wide variety of biological reactions, which include maintaining reduced forms of the enzymes important for protection against damage from high-energy oxygen radicals, the regulation of transcription factor activity, and the inhibition of apoptosis. here we report on a new member of the thioredoxin family of protein ...200312819103
mosquito larval consumption of toxic arborescent leaf-litter, and its biocontrol potential.previously we described the mosquito larvicidal properties of decomposed leaf-litter from deciduous trees, especially the alder alnus glutinosa (l) gaertn., due to toxic polyphenols and other secondary compounds. to further examine the biocontrol potential of toxic leaf-litter for mosquito control, feeding rates of third-instar mosquito larvae were assessed for examples of three genera: anopheles stephensi liston, aedes aegypti (l) and culex pipiens l. (diptera: culicidae). when immersed in a su ...200312823832
sublethal iridovirus disease of the mosquito aedes aegypti is due to viral replication not cytotoxicity.invertebrate iridescent viruses (iridoviridae) possess a highly cytotoxic protein. in mosquitoes (diptera: culicidae), invertebrate iridescent virus 6 (iiv-6) usually causes covert (inapparent) infection that reduces fitness. to determine whether sublethal effects of iiv-6 are principally due to cytotoxicity of the viral inoculum (which inhibits macromolecular synthesis in the host), or caused by replication of the virus larvae of the mosquito aedes aegypti (l) were exposed to untreated iiv-6 vi ...200312823836
natural skip oviposition of the mosquito aedes aegypti indicated by codominant genetic markers.this study examines the use of codominant restriction fragment length polymorphism (rflp) markers to estimate the number of sibling families found within and among oviposition sites used by the mosquito aedes aegypti (l) (diptera: culicidae). estimates were made using pairwise relatedness (rxy) calculations based on alleles shared between individuals. genotypes for eight laboratory mosquito families were determined at six rflp loci and the observed allele frequencies were used to generate simula ...200312823837
field evaluation of a lethal ovitrap against dengue vectors in brazil.field evaluation of a "lethal ovitrap" (lo) to control dengue vector aedes mosquitoes (diptera: culicidae), was undertaken in two brazilian municipalities, areia branca and nilopolis, in the state of rio de janeiro. the lo is designed to kill aedes via an insecticide-treated ovistrip (impregnated with deltamethrin). in each municipality, the intervention was applied to a group of 30 houses (10 los/house) and compared to 30 houses without los in the same neighbourhood. five los were put outside a ...200312823838
evaluation of selected traps as tools for conducting surveillance for adult aedes aegypti in thailand.the efficacy of the omnidirectional fay-prince trap (odfp), the centers for disease control wilton trap (wt), and sticky lures (sl) were assessed as a means of evaluating population densities of adult aedes aegypti in thailand. human landing/biting (l/b) collection was used as the reference method. the l/b collection method was significantly more effective at capturing ae. aegypti than any of the other methods, with 84% (1,072/1,272), 8.5% (108/1,272), 7.2% (92/1,272) and 0% (0/1,272) of mosquit ...200312825666
climatic and social risk factors for aedes infestation in rural thailand.an intense epidemic of dengue haemorrhagic fever in 1998 prompted the thai government to investigate the feasibility of focalized vector (aedes aegypti) control programmes. we tested for correlations of three indices of aedes larval abundance (housing index, container index and breteau index) against 38 socio-economic and four climatic variables. availability of public water wells, existence of transport services and proportion of tin houses were positively associated with larval indices. privat ...200312828549
comparison of the effect of two excipients (karite nut butter and vaseline) on the efficacy of cocos nucifera, elaeis guineensis and carapa procera oil-based repellents formulations against mosquitoes biting in ivory coast.repellents in the form of dermal pomades are recommended as a protection against awakening and bedtime mosquito bites. if synthesis repellents are available, they are nevertheless not common and the prices remain out of reach for the communities concerned. the people therefore have to resort more and more to traditional concoctions, some of which have been shown to be effective. after demonstrating that oil-based formulations (lotions, creams, pomades) of cocos nucifera (coconut), elaeis guineen ...200312847928
the structural determination of an insect sterol carrier protein-2 with a ligand-bound c16 fatty acid at 1.35-a resolution.yellow fever mosquito sterol carrier protein (scp-2) is known to bind to cholesterol. we report here the three-dimensional structure of the complex of scp-2 from aedes aegypti with a c16 fatty acid to 1.35-a resolution. the protein fold is exceedingly similar to the human and rabbit proteins, which consist of a five-stranded beta-sheet that exhibits strand order 3-2-1-4-5 with an accompanying layer of four alpha-helices that cover the beta-sheet. a large cavity exists at the interface of the lay ...200312855689
kinetics of cellular responses to intraperitoneal brugia pahangi infections in normal and immunodeficient mice.filarial infections evoke exuberant inflammatory responses in the peritoneal cavities of immunocompetent mice. clearance of infection appears to be dependent on complex interactions between b1 and b2 b lymphocytes, t cells, eosinophils, macrophages, and the products of these cells. in an earlier communication, we described the course of infection in normal immunocompetent mice. in this study, we utilize mice with well-characterized mutations that disable one or more effector components of adapti ...200312874313
identification of the people from whom engorged aedes aegypti took blood meals in florida, puerto rico, using polymerase chain reaction-based dna profiling.we used polymerase chain reaction-based dna profiling to construct allelic profiles for residents and visitors of 22 houses in florida, puerto rico, and human dna from blood meals in aedes aegypti that were collected in those homes. complete profiles were obtained for < or = 2 days after blood ingestion. eighteen percent of the meals came from two different people. there was no evidence of meals from > or = 2 people. eighty percent of the meal sources were identified, > 70% were taken from resid ...200312875293
benzoquinones from millipedes deter mosquitoes and elicit self-anointing in capuchin monkeys (cebus spp.).neotropical monkeys of the genus cebus anoint themselves by rubbing arthropods and plants against their pelage. a recent study has shown that free-ranging wedge-capped capuchin monkeys (c. olivaceus) in venezuela self-anoint with a benzoquinone-secreting millipede, an activity by which they are hypothesized to appropriate chemical deterrents of mosquitoes. to evaluate the plausibility of this hypothesis, female yellow fever mosquitoes (aedes aegypti) were presented with two millipede secretory c ...200312883771
deletions in the putative cell receptor-binding domain of sindbis virus strain mre16 e2 glycoprotein reduce midgut infectivity in aedes aegypti.the sindbis virus (alphavirus; togaviridae) strain mre16 efficiently infects aedes aegypti mosquitoes that ingest a blood meal containing 8 to 9 log(10) pfu of virus/ml. however, a small-plaque variant of this virus, mre16sp, poorly infects mosquitoes after oral infection with an equivalent titer. to determine the genetic differences between mre16 and mre16sp viruses, we have sequenced the mre16sp structural genes and found a 90-nucleotide deletion in the e2 glycoprotein that spans the 3' end of ...200312885905
improved molecular detection of dengue virus serotype 1 variants.the dengue virus molecular typing method described by lanciotti and coworkers (r. s. lanciotti, c. h. calisher, d. j. gubler, g. j. chang, and a. vance-vorndam, j. clin. microbiol. 30:545-551, 1992) is used worldwide for diagnosis and surveillance. however, it failed to detect denv-1 variants in cambodia due to a point mutation. we describe an improvement of the method that allows the detection of additional denv-1 strains, including potential variants.200312904404
the dynamics of interactions between plasmodium and the mosquito: a study of the infectivity of plasmodium berghei and plasmodium gallinaceum, and their transmission by anopheles stephensi, anopheles gambiae and aedes aegypti.knowledge of parasite-mosquito interactions is essential to develop strategies that will reduce malaria transmission through the mosquito vector. in this study we investigated the development of two model malaria parasites, plasmodium berghei and plasmodium gallinaceum, in three mosquito species anopheles stephensi, anopheles gambiae and aedes aegypti. new methods to study gamete production in vivo in combination with gfp-expressing ookinetes were employed to measure the large losses incurred by ...200312906877
the histone-like c-terminal extension in ribosomal protein s6 in aedes and anopheles mosquitoes is encoded within the distal portion of exon 3.in eukaryotic cells, ribosomal protein s6 (rps6) is the major phosphorylated protein on the small ribosomal subunit. in the mosquitoes aedes aegypti and aedes albopictus, the cdna encoding rps6 contains 300 additional nucleotides, relative to the drosophila homolog. the additional sequence encodes a 100-amino acid, lysine-rich c-terminal extension of the rps6 protein with 42-49% identity to histone h1 proteins from the chicken and other multicellular organisms. using mass spectrometry we now sho ...200312915181
recombinant american cockroach component, per a 1, reactive to ige of allergic thai patients.twelve similar recombinant per a 1 clones were produced from an american cockroach (cr) cdna library. the nucleotide sequence of a representative cline, i.e. clone a6, contained 579 base pairs (bp) and a 372 bp open reading frame (2-373) encoding 124 amino acids. a stop codon was found at position 374-376 followed by a 3' end untranslated region with an aataaa polyadenylation signal and a poly (a) tail. the estimated molecular mass of the 24 amino acid residue protein was 13.8 kda, with a predic ...200312931746
utility of comparative anchor-tagged sequences as physical anchors for comparative genome analysis among the culicidae.the development of comparative genetic maps in multiple species of mosquitoes could prove extremely useful in the search for those genes that contribute to mosquito vector competence or genes associated with other phenotypes of interest. to effectively compare these gene maps, markers must be developed that are based on chromosomal regions conserved throughout the culicidae. we designed 35 polymerase chain reaction (pcr) primer pairs based upon orthlogous exons in aedes aegypti and drosophila me ...200312932106
dengue and the risk of urban yellow fever reintroduction in são paulo state, brazil.to propose a mathematical method for the estimation of the basic reproduction number, r0, of urban yellow fever in a dengue-infested area.200312937709
growth characteristics of the veterinary vaccine candidate chimerivax-west nile (wn) virus in aedes and culex mosquitoes.in 1999 west nile (wn) virus was introduced to north america where this flavivirus has spread rapidly among wildlife (especially birds) transmitted by various species of mosquitoes (diptera: culicidae). increasing numbers of cases and deaths among humans, horses and other domestic animals require development of effective vaccines. 'chimerivax-west nile(vet)' is being developed for use as a veterinary vaccine to protect against wn infection. this chimeric virus contains the pre-membrane (prm) and ...200312941006
first report of the oriental mosquito aedes albopictus on the west african island of bioko, equatorial guinea.the invasive oriental mosquito aedes (stegomyia) albopictus (skuse) (diptera: culicidae) was detected on bioko island for the first time in november 2001. it was found to be well established breeding in artificial containers at planta, near malabo, the capital of equatorial guinea. associated species of mosquito larvae were aedes aegypti (l.), ae. africanus (theobald), culex near decens theobald, cx. duttoni theobald, cx. quinquefasciatus say, cx. tigripes de grandpré & de charmoy, eretmapodites ...200312941021
synthesis and repellent efficacy of a new chiral piperidine analog: comparison with deet and bayrepel activity in human-volunteer laboratory assays against aedes aegypti and anopheles stephensi.optically active (1s,2's)-2-methylpiperidinyl-3-cyclohexen-1-carboxamide (ss220) is a new synthetic arthropod repellent. a three-step synthesis based on a chiral diels-alder reaction and diastereomeric resolution of 2-methylpiperidine was developed to prepare the compound. quantitative laboratory assays using human volunteers compared the effectiveness of ss220 with the commonly used repellents deet and bayrepel against aedes aegypti (linnaeus) and anopheles stephensi liston mosquitoes. in two e ...200312943107
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