| identification and biochemical characterization of the anopheles gambiae 3-hydroxykynurenine transaminase. | spontaneous oxidation of 3-hydroxykynureine (3-hk), a metabolic intermediate of the tryptophan degradation pathway, elicits a remarkable oxidative stress response in animal tissues. in the yellow fever mosquito aedes aegypti the excess of this toxic metabolic intermediate is efficiently removed by a specific 3-hk transaminase, which converts 3-hk into the more stable compound xanthurenic acid. in anopheline mosquitoes transmitting malaria, xanthurenic acid plays an important role in plasmodium g ... | 2005 | 16262702 |
| repellent properties of celery, apium graveolens l., compared with commercial repellents, against mosquitoes under laboratory and field conditions. | in our search for new bioactive products against mosquito vectors, we reported the slightly larvicidal and adulticidal potency, but remarkable repellency of apium graveolens both in laboratory and field conditions. repellency of the ethanolic preparation of hexane-extracted a. graveolens was, therefore, investigated and compared with those of 15 commercial mosquito repellents including the most widely used, deet. hexane-extracted a. graveolens showed a significant degree of repellency in a dose- ... | 2005 | 16262746 |
| evaluation of ko-tab 1-2-3: a wash-resistant 'dip-it-yourself' insecticide formulation for long-lasting treatment of mosquito nets. | insecticide-treated nets (itn) are an important method of preventing malaria. to remain effective, they need to be re-treated with pyrethroid insecticide at approximately yearly intervals. systems for re-treating nets in africa are limited, and the vast majority of nets in use have never been treated or were treated only once. bayer environmental science (bes) has developed a long-lasting formulation 'ko-tab 1-2-3' which can be applied to the net post-manufacture, under field conditions, and ren ... | 2005 | 16269088 |
| 16s rrna gene-based identification of midgut bacteria from field-caught anopheles gambiae sensu lato and a. funestus mosquitoes reveals new species related to known insect symbionts. | field-collected mosquitoes of the two main malaria vectors in africa, anopheles gambiae sensu lato and anopheles funestus, were screened for their midgut bacterial contents. the midgut from each blood-fed mosquito was screened with two different detection pathways, one culture independent and one culture dependent. bacterial species determination was achieved by sequence analysis of 16s rrna genes. altogether, 16 species from 14 genera were identified, 8 by each method. interestingly, several of ... | 2005 | 16269761 |
| invasion and maintenance of dengue virus type 2 and type 4 in the americas. | dengue virus type 4 (denv-4) was first reported in the americas in 1981, where it caused epidemics of dengue fever throughout the region. in the same year, the region's first epidemic of dengue hemorrhagic fever was reported, caused by an asian strain of dengue virus type 2 (denv-2) that was distinct from the american subtype circulating previously. despite the importance of these epidemics, little is known about the rates or determinants of viral spread among island and mainland populations or ... | 2005 | 16282468 |
| a web-based multimedia spatial information system to document aedes aegypti breeding sites and dengue fever risk along the us-mexico border. | this paper describes a web-based multimedia spatial information system used to support a study of the re-invasion of aedes aegypti, the mosquito vector for dengue fever, in the deserts of the southwest united states/northwest mexico. the system was developed applying open geospatial consortium and world wide web consortium open specifications and using open source software. the system creates a sensory-rich environment, one which allows users to interact with the system to explore connections am ... | 2006 | 16290210 |
| efficacy of igr compound starycide 480 sc (triflumuron) against mosquito larvae in clear and polluted water. | an environmental friendly formulation starycide 480 sc (triflumuron-oms-2015 ), a new insect growth regulator with chitin synthesis inhibitor type mode of action was evaluated against mosquito larvae in laboratory and small-scale field trials carried out in and around delhi. | 2005 | 16294809 |
| discrimination of aedes aegypti (diptera: culicidae) laboratory lines based on wing geometry. | recent techniques of geometric morphometrics were applied to the study of four thailand laboratory lines of the dengue vector aedes aegypti. these lines differed by their geographic origin and the number of generations spent in the laboratory. using a phase contrast microscope, a set of sixteen landmarks of the wings could be identified. a subsequent procrustean superposition analysis produced the corresponding size and shape variables which were statistically analyzed. size showed a significant ... | 2005 | 16295537 |
| surveillance of dengue vector at thiruvananthapuram (kerala) international airport. | a survey of aedes (stegomyia) mosquitoes was undertaken in and around the international airport at thiruvananthapuram during premonsoon season. an attempt has been made in this paper to elaborate on the presence of risk potential for dengue /yellow fever at the airport with the detection of aedes breeding. the entomological indices have also been discussed with regard to presence of potential wet containers and rate of infestation by aedes mosquitoes. the airport area was searched for aedes (ste ... | 2004 | 16295677 |
| function and evolution of a mosquito salivary protein family. | saliva of blood-sucking arthropods contains a complex and diverse mixture of antihemostatic, antiinflammatory, and immunomodulatory compounds. the d7 salivary family of proteins is abundantly expressed in blood-feeding diptera and is distantly related to the odorant-binding protein superfamily. in mosquitoes, two subfamilies exist, the long and short d7 proteins. ticks and kissing bugs evolved salivary lipocalins that act as efficient scavengers of biogenic amines, and a similar function was pos ... | 2006 | 16301315 |
| genetic lineages in the yellow fever mosquito aedes (stegomyia) aegypti (diptera: culicidae) from peru. | the yellow fever mosquito aedes aegypti was introduced in peru in 1852 and was considered to be eradicated in 1958. in 2001, ae. aegypti had been recorded in 15 out of 24 peruvian departments. peru has great ecological differences between the east and west sides of andes. because of this, we consider that ae. aegypti populations of both east and west sides can have a genetically distinct population structure. in this study we examined genetic variability and genealogical relationships among thre ... | 2005 | 16302064 |
| clade replacements in dengue virus serotypes 1 and 3 are associated with changing serotype prevalence. | the evolution of dengue virus (denv) is characterized by phylogenetic trees that have a strong temporal structure punctuated by dramatic changes in clade frequency. to determine the cause of these large-scale phylogenetic patterns, we examined the evolutionary history of denv serotype 1 (denv-1) and denv-3 in thailand, where gene sequence and epidemiological data are relatively abundant over a 30-year period. we found evidence for the turnover of viral clades in both serotypes, most notably in d ... | 2005 | 16306584 |
| dirofilariasis in argentina: historical review and first report of dirofilaria immitis in a natural mosquito population. | argentina is one of the four south american countries where the presence of dirofilaria immitis is currently confirmed. the objective of this study was to review information on dirofilariasis in the country, and to report our recent findings on mosquito vectors. since the first report of dogs with unidentified microfilariae in 1926, d. immitis was found in seven provinces and canine prevalence ranged 0-71% at local scale. national prevalence was 8% by the end of the 1980s and current information ... | 2006 | 16310953 |
| identification and composition of cuticular hydrocarbons of the major afrotropical malaria vector anopheles gambiae s.s. (diptera: culicidae): analysis of sexual dimorphism and age-related changes. | forty-eight cuticular hydrocarbons (chcs) were characterized by gas chromatography-mass spectrometry from the epicuticular surface of the major afrotropical malaria vector anopheles gambiae. the hydrocarbons identified were 14 n-alkanes, 16 monomethyl alkanes, 13 dimethyl alkanes, 5 alkenes, with main-chain lengths ranging from c(17) to c(47), and the results are consistent with those from other culicidae species. qualitative differences were not observed between laboratory pools of three female ... | 2005 | 16320293 |
| outlook of dengue in malaysia: a century later. | dengue continues to be a major health threat to malaysia a century after its first reported outbreak in 1902. examination of the available outbreak data suggested that a major df/dhf outbreak occurred in malaysia in a cyclical pattern of approximately every 8 years. all four dengue virus serotypes are found co-circulating in malaysia, but after the first and only major outbreak involving den-4 in 1960's, only den-1, den-2 and den-3 were associated with df/dhf outbreaks. it is argued that perhaps ... | 2002 | 16329552 |
| the angiotensin-converting enzyme (ace) gene family of anopheles gambiae. | members of the m2 family of peptidases, related to mammalian angiotensin converting enzyme (ace), play important roles in regulating a number of physiological processes. as more invertebrate genomes are sequenced, there is increasing evidence of a variety of m2 peptidase genes, even within a single species. the function of these ace-like proteins is largely unknown. sequencing of the a. gambiae genome has revealed a number of ace-like genes but probable errors in the ensembl annotation have left ... | 2005 | 16329762 |
| spray-dried bacillus thuringiensis serovar israelensis formulations for control of aedes aegypti larvae. | suspensions containing 0.25 and 1.25 g/liter of bacillus thuringiensis subsp. israelensis (bti) spore-toxin complex were spray-dried by using maltodextrin de-6, corn starch, and nixtamalized corn flour (25 g/liter) as materials to entrap active delta-endotoxin. the inlet air temperature of the drier was kept constant at 141 degrees c and the outlet temperature was maintained at 60 or 70 degrees c. the probit analysis of the concentration-mortality response of third instars of aedes aegypti (l.) ... | 2005 | 16334315 |
| genetic structure of anopheles gambiae populations on islands in northwestern lake victoria, uganda. | alternative means of malaria control are urgently needed. evaluating the effectiveness of measures that involve genetic manipulation of vector populations will be facilitated by identifying small, genetically isolated vector populations. the study was designed to use variation in microsatellite markers to look at genetic structure across four lake victoria islands and two surrounding mainland populations and for evidence of any restriction to free gene flow. | 2005 | 16336684 |
| bacillus thuringiensis subsp. israelensis cyt1aa synergizes cry11aa toxin by functioning as a membrane-bound receptor. | bacillus thuringiensis subsp. israelensis produces crystal proteins, cry (4aa, 4ba, 10aa, and 11aa) and cyt (1aa and 2ba) proteins, toxic to mosquito vectors of human diseases. cyt1aa overcomes insect resistance to cry11aa and cry4 toxins and synergizes the toxicity of these toxins. however, the molecular mechanism of synergism remains unsolved. here, we provide evidence that cyt1aa functions as a receptor of cry11aa. sequential-binding analysis of cyt1aa and cry11aa revealed that cyt1aa binding ... | 2005 | 16339907 |
| comparison of immunoreactivity to serotonin, fmrfamide and scpb in the gut and visceral nervous system of larvae, pupae and adults of the yellow fever mosquito aedes aegypti. | in all life stages, the gut of the mosquito is innervated by a small number (typically 4) of central neurons immunoreactive to serotonin (si). the serotonergic system appears to pass through metamorphosis largely intact, despite extensive remodeling of the gut. axons immunoreactive to antibodies raised against molluscan fmrfamide (rf-i) constitute peptidergic innervation that anatomically parallels the serotonergic system. in the larva, two clusters of 3 neurons project to the anterior regions o ... | 2005 | 16341252 |
| distribution, frequency, and diversity of bacillus thuringiensis in an animal feed mill. | bacillus thuringiensis was isolated from 36 of 50 residue samples obtained from an animal feed mill (a stored-product environment). of 710 selected colonies having bacillus cereus-b. thuringiensis morphology isolated from the samples, 477 were classified as b. thuringiensis because of production of parasporal delta-endotoxin crystals. there was a diverse population of b. thuringiensis, as revealed by differentiation of the isolates into 36 subgroups by using (i) their spectra of toxicity to the ... | 1992 | 16348699 |
| expression of cryiva and cryivb genes, independently or in combination, in a crystal-negative strain of bacillus thuringiensis subsp. israelensis. | the cryiva and cryivb genes, encoding the 125- and 135-kda proteins, respectively, of bacillus thuringiensis subsp. israelensis, were cloned either alone or together into a shuttle vector and expressed in a nontoxic strain of b. thuringiensis subsp. israelensis. the cryivb protein was produced at a high level during sporulation and accumulated as inclusions; in contrast, the cryiva polypeptide did not form such structures unless it was cloned on a higher-copy-number plasmid. transcriptional fusi ... | 1993 | 16349095 |
| asn183 in alpha5 is essential for oligomerisation and toxicity of the bacillus thuringiensis cry4ba toxin. | the proposed toxicity mechanism of the bacillus thuringiensis cry insecticidal proteins involves membrane penetration and lytic pore formation of the alpha4-alpha5 hairpins in the target larval midgut cell membranes. in this study, alanine substitutions of selected polar residues (tyr(178), gln(180), asn(183), asn(185), and asn(195)) in the hydrophobic helix-alpha5 of the cry4ba mosquito-larvicidal protein were initially conducted via pcr-based directed mutagenesis. upon iptg induction, all the ... | 2006 | 16356469 |
| host range, amplification and arboviral disease emergence. | etiologic agents of arboviral diseases are primarily zoonotic pathogens that are maintained in nature in cycles involving arthropod transmission among a variety of susceptible reservoir hosts. in the simplest form of human exposure, spillover occurs from the enzootic cycle when humans enter zoonotic foci and/or enzootic amplification increases circulation near humans. examples include eastern (eeev) and western equine encephalitis viruses (weev), as well as west nile (wnv), st. louis encephaliti ... | 2005 | 16358422 |
| efficacy of thermal fog application of deltacide, a synergized mixture of pyrethroids, against aedes aegypti, the vector of dengue. | we evaluated the efficacy of indoor and peridomestic thermal fog applications of deltacide, a synergized mixture of pyrethroids (s-bioallethrin 0.7% w/v, deltamethrin 0.5% w/v and piperonyl butoxide 8.9% w/v) against adult populations of aedes aegypti in chennai, tamil nadu, india. we bioassayed adult caged mosquitoes, counted indoor resting and human landing adult mosquitoes and assessed the percentage of potential breeding sites with aedes larvae. the bioassay mortalities indicated that the kn ... | 2005 | 16359411 |
| molecular cloning and functional characterization of an aspartic protease from the hard tick haemaphysalis longicornis. | haemaphysalis longicornis cdna encoding an aspartic protease (longepsin) was identified from a midgut cdna library. the longepsin cdna contains 1176bp that code for 392 amino acid residues with a predictable molecular weight of 39.3kda. the cdna has a signal peptide sequence associated with the n-terminal domains and domain structure analysis revealed that the deduced protein has two aspartic acid residues that are characteristic of a single active site for aspartic proteases. this novel longeps ... | 2006 | 16360947 |
| geographic distribution and breeding site preference of aedes albopictus and aedes aegypti (diptera: culicidae) in cameroon, central africa. | presence in cameroon of the recently introduced aedes (stegomyia) albopictus (skuse) in association with the indigenous aedes aegypti (l.) raises public heath concerns because it might alter the risk of arbovirus transmission. the breeding site and distribution of the two stegomyia species are updated and reported following entomological surveys carried out in 22 localities throughout cameroon, with a total of 1,353 containers with water visited. ae. aegypti was found in every location sampled, ... | 2005 | 16363155 |
| insecticide susceptibility of aedes aegypti and aedes albopictus across thailand. | aedes aegypti (l.) and aedes albopictus (skuse), two important vectors of dengue fever and dengue hemorrhagic fever, were collected from mae sot, nakhon sawan, nakhon ratchasima, surat thani, and phatthalung, thailand, from july 2003 to april 2004. the patterns of insecticide susceptibility to temephos, malathion, and permethrin of both ae. aegypti and ae. albopictus larvae were determined. ae. aegypti from all study sites were resistant to permethrin, they but were susceptible to malathion. res ... | 2005 | 16363166 |
| effectiveness of methoprene, an insect growth regulator, against temephos-resistant aedes aegypti populations from different brazilian localities, under laboratory conditions. | the susceptibility of aedes aegypti (l.) larvae from several brazilian populations to the juvenile hormone analog methoprene and the organophosphate insecticide temephos were investigated. populations from natal (northeastern region), macapá (northern region), and jardim américa, rio de janeiro (southeastern region) are temephos-resistant (rr90 = 24.4, 13.3, and 15.8, respectively), whereas populations from presidente prudente (southeastern region) and porto velho (northern region) exhibit only ... | 2005 | 16363168 |
| blood feeding patterns of aedes aegypti and aedes albopictus in thailand. | aedes aegypti (l.) and aedes albopictus (skuse) were collected with aspirators from mae sot, nakhon sawan, nakhon ratchasima, surat thani, and phatthalung study sites in thailand from july 2003 though april 2004. the sandwich-b enzyme-linked immunosorbent assay was used to analyze 1,021 blood-fed specimens. ae. aegypti almost exclusively fed on humans (99%, 658/664) in single host species, and 97% (86/88) of multiple-host bloodmeals included at least one human host. a low frequency of other host ... | 2005 | 16363170 |
| vertical and venereal transmission of chandipura virus (rhabdoviridae) by aedes aegypti (diptera: culicidae). | experiments in the laboratory documented vertical and venereal transmission of chandipura virus (chpv) in aedes aegypti (l.). the minimum filial infection rate among the progeny of infected females was 1.2%; the rate among male and female progeny was 0.9 and 1.4%, respectively. the venereal infection rate of chpv among inseminated females was 32.7%. our study indicates the possible occurrence of vertical and venereal transmission of chpv in insect vectors. | 2005 | 16363175 |
| a plasmodium whole-genome synteny map: indels and synteny breakpoints as foci for species-specific genes. | whole-genome comparisons are highly informative regarding genome evolution and can reveal the conservation of genome organization and gene content, gene regulatory elements, and presence of species-specific genes. initial comparative genome analyses of the human malaria parasite plasmodium falciparum and rodent malaria parasites (rmps) revealed a core set of 4,500 plasmodium orthologs located in the highly syntenic central regions of the chromosomes that sharply defined the boundaries of the var ... | 2005 | 16389297 |
| a bacillus thuringiensis s-layer protein involved in toxicity against epilachna varivestis (coleoptera: coccinellidae). | the use of bacillus thuringiensis as a biopesticide is a viable alternative for insect control since the insecticidal cry proteins produced by these bacteria are highly specific; harmless to humans, vertebrates, and plants; and completely biodegradable. in addition to cry proteins, b. thuringiensis produces a number of extracellular compounds, including s-layer proteins (slp), that contribute to virulence. the s layer is an ordered structure representing a proteinaceous paracrystalline array whi ... | 2006 | 16391064 |
| heterologous expression of an entamoeba histolytica chitin synthase in saccharomyces cerevisiae. | chitin in the cyst wall of entamoeba histolytica is made by two chitin synthases (chs), one of which is unique (ehchs-1) and one of which resembles those of insects and nematodes (ehchs-2). ehchs-1 is deposited chitin in the lateral wall of transformed saccharomyces cerevisiae chs mutants, independent of accessory proteins (chs4p to chs7p) required by yeast chs3p. | 2006 | 16400183 |
| cage trials using an endogenous meiotic drive gene in the mosquito aedes aegypti to promote population replacement. | control of arthropod-borne diseases based on population replacement with genetically modified non-competent vectors has been proposed as a promising alternative to conventional control strategies. due to likely fitness costs associated with vectors manipulated to carry anti-pathogen effector genes, the effector genes will need to be coupled with a strong drive system to rapidly sweep them into natural populations. endogenous meiotic drive systems have strong and stable population replacement pot ... | 2006 | 16407347 |
| quantitative analysis of dengue-2 virus rna during the extrinsic incubation period in individual aedes aegypti. | dengue virus-2 (denv-2) rna was quantified from the midgut and legs of individual aedes aegypti at each of 14 days postinfectious blood meal (dpi) in a denv-2 susceptible strain from chetumal, mexico. a sybr green i based strand-specific, quantitative real-time reverse transcription-polymerase chain reaction (rt-pcr) assay was developed. the lower detection and quantitation limits were 20 and 200 copies per reaction, respectively. amounts of positive and negative strand viral rna strands were co ... | 2006 | 16407358 |
| acmnpv in permissive, semipermissive, and nonpermissive cell lines from arthropoda. | insect cell lines from arthropoda represented by lepidoptera, coleoptera, diptera, and homoptera were evaluated for their ability to support replication of acmnpv. in addition, some of the cell lines that were refractive to acmnpv were tested with acmnpv hsp70 red, a recombinant carrying the red fluorescent protein (rfp) gene, for their ability to express this protein after inoculation. of the 10 lepidopteran cell lines tested, only three cell lines from helicoverpa zea (bcirl-hz-am1), lymantria ... | 2005 | 16409117 |
| a new black fly isolate of bacillus thuringiensis autoagglutinating strain highly toxic to simulium pertinax (kollar) (diptera, simuliidae) larvae. | formulations containing the entomopathogenic bacillus thuringiensis serovar israelensis strain ips-82 has been widely applied for mosquito control around the world. strain ips-82 is highly active against aedes aegypti but less active against other well-known vectors such as culex quinquefasciatus and simulium spp. larvae. eighteen strains of b. thuringiensis were isolated from simulium pertinax larvae naturally occurring in rivers of southeast brazil with one demonstrating special toxic effects. ... | 2006 | 16410971 |
| [cultural conceptions on dengue in urban contexts in mexico]. | to explore the conceptual dimensions of dengue in the urban context, aiming at creating hypotheses about community attitudes toward prevention campaigns. | 2006 | 16410993 |
| genomic analysis of a 1 mb region near the telomere of hessian fly chromosome x2 and avirulence gene vh13. | to have an insight into the mayetiola destructor (hessian fly) genome, we performed an in silico comparative genomic analysis utilizing genetic mapping, genomic sequence and est sequence data along with data available from public databases. | 2006 | 16412254 |
| eastern cottontail rabbits (sylvilagus floridanus) develop west nile virus viremias sufficient for infecting select mosquito species. | the potential of the eastern cottontail rabbit (ctr; sylvilagus floridanus) to contribute to an enzootic west nile virus (wnv) cycle was demonstrated by characterizing the wnv viremia profile of 15 ctrs and demonstrating that mosquitoes could become infected by feeding on these ctrs. eight ctrs were infected with a titer of 10(5.0) cell-infectious dose 50% endpoints (cid50s) of wnv (ny99-crow) by needle and seven ctrs by bite of one or more wnv-infected mosquitoes. there were no marked differenc ... | 2005 | 16417430 |
| malaria vectors in angola: distribution of species and molecular forms of the anopheles gambiae complex, their pyrethroid insecticide knockdown resistance (kdr) status and plasmodium falciparum sporozoite rates. | malaria is by far the greatest cause of morbidity and mortality in angola, being responsible for 50% of all outpatient attendance and around 22% of all hospital deaths, yet by 2003 only 2% of under-5s used insecticide-treated nets. entomological studies are an essential foundation for rational malaria control using insecticide-treated nets and indoor residual spraying, but there have been no published studies of malaria vectors in angola over the 27 years of the civil war, to its end in 2002. th ... | 2006 | 16420701 |
| effect of temperature and insecticide stresses on aedes aegypti larvae and their influence on the susceptibility of mosquitoes to dengue-2 virus. | two major factors, higher temperatures and the application of insecticides, can drastically alter the genetic structure of a vector mosquito population. due to these two stresses, the majority of the population gets wiped out, but the ones that withstand the stress and survive are likely to pass on survivability, and have an altered physiology. our study shows that exposures to higher temperatures and ddt during the larval stage affects their susceptibility as adult mosquitoes to the den-2 virus ... | 2005 | 16438138 |
| a preliminary study on in vitro transmission of dirofilaria immitis infective stage larvae by aedes aegypti (l.) (diptera: culicidae). | this study was performed to study an in vitro transmission of infective stage larvae from the mosquito proboscis. there were five experiments with 949 mosquitoes. liverpool strain of aedes aegypti (l.) were used in this study. they were allowed to feed on d. immitis infected dogs with different microfilarial levels which were 1,650, 1,950, 9,000, 9,250, and 11,550 microfilariae per one ml of blood. mosquitoes were forced to feed on solution (5% sucrose in 5% dog serum) in capillary tubes for 20 ... | 2005 | 16438186 |
| three indigenous thai medicinal plants for control of aedes aegypti and culex quinquefasciatus. | the potential larvicidal activity and insect growth regulator (igr) properties of three selected indigenous medicinal thai plants were tested against two species of mosquito with special reference to the late 3rd and early 4th instar larvae (l3 and l4, respectively). in case of larvicidal activity, thevetia peruviana was the most potent, followed by pueraria mirifica, and butea superba was the least effective. in all cases, the late 3rd instar was more susceptible than the early 4th instar larva ... | 2005 | 16438204 |
| detection of dengue virus serotype 3 by reverse transcription-polymerase chain reaction in aedes aegypti (diptera, culicidae) captured in manaus, amazonas. | the detection of dengue virus serotypes from aedes aegypti in manaus, state of amazonas was carried out using the reverse transcription-polymerase chain reaction technique. fourteen pools out 82 (17.1%) were positive for denv3, providing a minimal infection rate of 2.1% of all analyzed infected female specimens of three different areas of the city. | 2006 | 16444413 |
| use of carbon-13 as a population marker for anopheles arabiensis in a sterile insect technique (sit) context. | monitoring of sterile to wild insect ratios in field populations can be useful to follow the progress in genetic control programmes such as the sterile insect technique (sit). of the numerous methods for marking insects most are not suitable for use in mass rearing and mass release. suitable ones include dye marking, genetic marking and chemical marking. | 2006 | 16445865 |
| prevalence and seasonality of ascogregarina culicis (apicomplexa: lecudinidae) in natural populations of aedes aegypti (diptera: culicidae) from temperate argentina. | ascogregarina infections from south america were recently documented in brazil and argentina. the aim of this study was to report our recent findings on the prevalence and seasonality of ascogregarina culicis in aedes aegypti adults from temperate argentina. between december 2003 and may 2005, 391 females of ae. aegypti were captured in two areas of greater buenos aires. overall prevalence of a. culicis was 21.2% (83/391), and a significant difference was observed between both areas (28.4% vs. 8 ... | 2006 | 16445937 |
| regulation of lipid metabolism genes, lipid carrier protein lipophorin, and its receptor during immune challenge in the mosquito aedes aegypti. | in the mosquito aedes aegypti, the expression of two fat body genes involved in lipid metabolism, a lipid carrier protein lipophorin (lp) and its lipophorin receptor (lprfb), was significantly increased after infections with gram (+) bacteria and fungi, but not with gram (-) bacteria. the expression of these genes was enhanced after the infection with plasmodium gallinaceum. rna interference (rnai) knockdown of lp strongly restricted the development of plasmodium oocysts, reducing their number b ... | 2006 | 16449228 |
| insights into the role of gp63-like proteins in lower trypanosomatids. | any actual understanding of trypanosomatids in general requires a comprehensive analysis of the less-specialized species as thorough as our knowledge of the more specialized leishmania and trypanosoma. in this context, we have shown by antibody cross-reactivity that purified extracellular metallopeptidases from phytomonas françai, crithidia deanei (cured strain) and crithidia guilhermei share common epitopes with the leishmanial gp63. flow cytometry and fluorescence microscopy analyses indicated ... | 2006 | 16451193 |
| txp40, a ubiquitous insecticidal toxin protein from xenorhabdus and photorhabdus bacteria. | xenorhabdus and photorhabdus are gram-negative bacteria that produce a range of proteins that are toxic to insects. we recently identified a novel 42-kda protein from xenorhabdus nematophila that was lethal to the larvae of insects such as galleria mellonella and helicoverpa armigera when it was injected at doses of 30 to 40 ng/g larvae. in the present work, the toxin gene txp40 was identified in another 59 strains of xenorhabdus and photorhabdus, indicating that it is both highly conserved and ... | 2006 | 16461722 |
| aedes aegypti (l.) and aedes polynesiensis marks (diptera: culicidae) in moorea, french polynesia: a study of adult population structures and pathogen (wuchereria bancrofti and dirofilaria immitis) infection rates to indicate regional and seasonal epidemiological risk for dengue and filariasis. | populations of aedes aegypti (l.) and aedes polynesiensis (marks) on moorea island, french polynesia, the local vectors of dengue and filariasis, respectively, were sampled by landing/biting collection at nine localities on the east, north, and west coasts, during the late dry season, early and late wet season (september-may) 2003 and 2004, to investigate epidemiologically important features of the populations and compare them between regions and months. biting rates of both species tended to in ... | 2005 | 16465747 |
| use of the pupal survey technique for measuring aedes aegypti (diptera: culicidae) productivity in puerto rico. | the hypothesis tested was that most pupae of aedes aegypti are produced in a few types of containers so that vector control efforts could concentrate on eliminating the most productive ones and thus prevent dengue outbreaks. pupal surveys were conducted twice in 2004 in an urban area in southern puerto rico. a total 35,030 immature mosquitoes (iii and iv instars, pupae) was counted in 1,367 containers found with water in 624 premises during the first survey. only pupae were counted in the second ... | 2006 | 16474086 |
| rna secondary structure in the coding region of dengue virus type 2 directs translation start codon selection and is required for viral replication. | dengue virus is a positive-strand rna virus and a member of the genus flavivirus, which includes west nile, yellow fever, and tick-borne encephalitis viruses. flavivirus genomes are translated as a single polyprotein that is subsequently cleaved into 10 proteins, the first of which is the viral capsid (c) protein. dengue virus type 2 (denv2) and other mosquito-borne flaviviruses initiate translation of c from a start codon in a suboptimal context and have multiple in-frame augs downstream. here, ... | 2006 | 16474125 |
| two unusual rotenoid derivatives, 7a-o-methyl-12a-hydroxydeguelol and spiro-13-homo-13-oxaelliptone, from the seeds of derris trifoliata. | the crude methanol extract of the seeds of derris trifoliata showed potent and dose dependent larvicidal activity against the 2nd instar larvae of aedes aegypti. from this extract two unusual rotenoid derivatives, a rotenoloid (named 7a-o-methyl-12a-hydroxydeguelol) and a spirohomooxarotenoid (named spiro-13-homo-13-oxaelliptone), were isolated and characterised. in addition a rare natural chromanone (6,7-dimethoxy-4-chromanone) and the known rotenoids rotenone, tephrosin and dehydrodeguelin wer ... | 2006 | 16483619 |
| toxin-binding proteins from midgut epithelium membranes of anopheles stephensi larvae. | proteins of 65 and 57 kd were isolated from the apical membranes of midgut epithelium of anopheles stephensi larvae by affinity chromatography. these proteins can specifically bind endotoxin cry11a and activate toxin cry4b (cry4b-tox) under conditions of ligand blotting, and both cry proteins compete for this binding. at least in the case of cry4b-tox, the binding with 65 and 57 kd proteins is reversible. the ability of the products of limited proteolysis of cry11a and cry4b to bind the 65 and 5 ... | 2006 | 16489916 |
| gata factor translation is the final downstream step in the amino acid/target-of-rapamycin-mediated vitellogenin gene expression in the anautogenous mosquito aedes aegypti. | ingestion of blood is required for vector mosquitoes to initiate reproductive cycles determining their role as vectors of devastating human diseases. nutritional signaling plays a pivotal role in regulating mosquito reproduction. transcription of yolk protein precursor genes is repressed until mosquitoes take blood. previously, we have shown that to signal the presence of blood in the gut, mosquitoes utilize the target-of-rapamycin (tor) pathway. the tor signaling pathway transduces the amino ac ... | 2006 | 16490782 |
| identification of aedes aegypti and its respective life stages by real-time polymerase chain reaction. | an aedes aegypti-specific, fluorogenic probe hydrolysis (taq-man), polymerase chain reaction assay was developed for real-time screening using a field-deployable thermocycler. laboratory-based testing of a. aegypti, a. aegypti (trinidad strain), culex pipiens, culex quinquefasciatus, anopheles stephensi, and ochlerotatus taeniorhynchus individual adult mosquitoes and mixed pools (n = 10) demonstrated 100% concordance in both in vitro sensitivity (six of six samples) and specificity (10 of 10 sam ... | 2005 | 16491948 |
| peptidases and gp63-like proteins in herpetomonas megaseliae: possible involvement in the adhesion to the invertebrate host. | the cell-associated and extracellular peptidases of herpetomonas megaseliae grown in brain-heart infusion and in modified roitman's complex media were analyzed by measuring peptidase activity on gelatin, casein and hemoglobin in zymograms. casein was the best proteinaceous substrate for the peptidase detection on both growth conditions. however, no proteolytic activity was detected when hemoglobin was used. our results showed that cellular cysteine peptidase (115-100, 40 and 35 kda) and metallop ... | 2006 | 16500661 |
| identification and characterization of an odorant receptor from the west nile virus mosquito, culex quinquefasciatus. | members of the culex pipens mosquito group including c. quinquefasciatus are responsible for the transmission of bancroftian filarisis as well as west nile virus (wnv) in the united states. as is the case for other mosquitoes, the host preference of this disease vector relies on olfaction and accordingly mediated via g-protein coupled signal transduction pathways. here, we identify and characterize cqor7, the first candidate member of the odorant receptor gene family from c. quinquefasciatus. cq ... | 2006 | 16503478 |
| repellent and deterrent effects of ss220, picaridin, and deet suppress human blood feeding by aedes aegypti, anopheles stephensi, and phlebotomus papatasi. | a series of behavioral tests with aedes aegypti (l.), anopheles stephensi liston, mosquitoes, and the sand fly phlebotomus papatasi scopoli in the presence of deet, ss220, and picaridin topically applied to the skin of human volunteers showed that the insects were deterred from feeding on and repelled from surfaces emanating the compounds. when offered a 12- or 24-cm2 area of skin, one-half treated with compound and one-half untreated, the insects fed almost exclusively on untreated skin. the sa ... | 2006 | 16506445 |
| molecular and morphological characterization of aedes albopictus in northwestern greece and differentiation from aedes cretinus and aedes aegypti. | the presence of aedes albopictus (skuse) was recently confirmed for the first time in northwestern greece. this location is within the distribution range of a morphologically similar species, aedes cretinus edwards, and is a potentially favorable region for the reintroduction of aedes aegypti (l.). it was thus compelling to use methods in addition to morphology-based keys to correctly identify specimens badly damaged, rubbed, or otherwise altered in their external characteristics. it was decided ... | 2006 | 16506446 |
| evaluation of novel insecticides for control of dengue vector aedes aegypti (diptera: culicidae). | insecticides are one of the major tools for controlling vector populations and for reducing the transmission of human pathogens. however, there are few new insecticides being developed and marketed for vector control. herein, we report on the toxicity of six novel insecticides to both adult and larval aedes aegypti (l). and the toxicity of three novel insect growth regulators (igrs) to larvae. four insecticides were highly or moderately toxic to larvae with lc50 values of 16 (chlorfenapyr), 70 ( ... | 2006 | 16506447 |
| mosquito larvicidal activity of active constituent derived from chamaecyparis obtusa leaves against 3 mosquito species. | mosqutio larvicidal activity of chamaecyparis obtusa leaf-derived materials against the 4th-stage larvae of aedes aegypti (l.), ochlerotatus togoi (theobald), and culex pipiens pallens (coquillett) was examined in the laboratory. a crude methanol extract of c. obtusa leaves was found to be active (percent mortality rough) against the 3 species larvae; the hexane fraction of the methanol extract showed a strong larvicidal activity (100% mortality) at 100 ppm. the bioactive component in the c. obt ... | 2005 | 16506565 |
| laboratory and field evaluation of hilmilin against mosquitoes. | hilmilin (diflubenzuron), an insect growth regulator, was tested for efficacy against anopheles stephensi, anopheles culicifacies, aedes aegypti, and culex quinquefasciatus in the laboratory and in field conditions. fifty percent and 90% lethal concentrations (lc50 and lc90) of hilmilin formulations were determined by exposing early 4th-stage larvae to serial dilutions of the formulation, and data were subjected to log probit analysis. two doses (0.004 and 0.008 g/m2) were applied in different b ... | 2005 | 16506568 |
| pyrethroid insecticide-resistant strain of aedes aegypti from cuba induced by deltamethrin selection. | a sample of aedes aegypti l. from santiago de cuba with a high level of deltamethrin resistance (113.7 x at the 50% lethal concentration [lc50]), was subjected to deltamethrin selection to determine the capacity of this population to evolve higher resistance under intensive laboratory selection pressure, to characterize that resistance, to attempt to identify some of the mechanisms involved, and to use it as a reference strain for future molecular research. high resistance developed after 12 gen ... | 2005 | 16506569 |
| spinosad: a new larvicide against insecticide-resistant mosquito larvae. | among the characteristics of spinosad that are worth noting is its environmentally favorable toxicity profile. it is a compound of biological origin, whose insecticide action is highly effective against a great number of insects. laboratory larval bioassays of spinosad on aedes aegypti, culex quinquefasciatus, and anopheles gambiae (specimens that were either susceptible or resistant to pyrethroids, carbamates, and organophosphates) showed that this product had a lethal action (mortality after 2 ... | 2005 | 16506584 |
| study on susceptibility status in aquatic and adult stages of aedes aegypti and ae. albopictus against insecticides at international airports of south india. | a study on susceptibility status in aquatic and adult stages of aedes aegypti and ae. albopictus was undertaken at international airports of thiruvananthapuram and cochin located in southern india. who standard test kits were used to conduct insecticide susceptibility tests against various organophosphates, organochlorines, carbamates and synthetic pyrethroids. the results indicate that adult aedes aegypti and ae. albopictus were resistant to ddt and dieldrin, but susceptible to propoxur, fenitr ... | 2004 | 16509254 |
| purification and crystallization of dengue and west nile virus ns2b-ns3 complexes. | both dengue and west nile virus infections are an increasing risk to humans, not only in tropical and subtropical areas, but also in north america and parts of europe. these viral infections are generally transmitted by mosquitoes, but may also be tick-borne. infection usually results in mild flu-like symptoms, but can also cause encephalitis and fatalities. approximately 2799 severe west nile virus cases were reported this year in the united states, resulting in 102 fatalities. with this alarmi ... | 2006 | 16511290 |
| conjugal transfer of a toxin-coding megaplasmid from bacillus thuringiensis subsp. israelensis to mosquitocidal strains of bacillus sphaericus. | both bacillus sphaericus and bacillus thuringiensis subsp. israelensis produce mosquitocidal toxins during sporulation and are extensively used in the field for control of mosquito populations. all the known toxins of the latter organism are known to be encoded on a large plasmid, pbtoxis. in an attempt to combine the best properties of the two bacteria, an erythromycin resistance-marked pbtoxis plasmid was transferred to b. sphaericus by a mating technique. the resulting transconjugant bacteria ... | 2006 | 16517620 |
| response of aedes aegypti (diptera: culicidae) larvae to three xenobiotic exposures: larval tolerance and detoxifying enzyme activities. | the ability of mosquito larvae to tolerate toxic compounds (temephos, bacillus thuringiensis var. israelensis, toxic vegetable leaf litter) was examined on a laboratory larval strain of aedes aegypti l. bioassays and detoxifying enzyme activity measurements were performed to compare tolerance/resistance capacities. the possibility of a functional plasticity of detoxifying equipment was investigated through experimental determination of the inductive effect of each xenobiotic within a given gener ... | 2006 | 16519308 |
| a new clothing impregnation method for personal protection against ticks and biting insects. | the efficacy and residual activity of a factory-based, permethrin-impregnated military battle dress uniform (bdu) using a new polymer-coating technique has been evaluated by laboratory and field testing during deployment to afghanistan and compared with two commercially available, widely used dipping methods. residual permethrin concentrations and remaining contact toxicities on treated fabrics before laundering, after up to 100 launderings as well as after being worn-out during deployment were ... | 2006 | 16524779 |
| evaluating the costs of mosquito resistance to malaria parasites. | costly resistance mechanisms have been cited as an explanation for the widespread occurrence of parasitic infections, yet few studies have examined these costs in detail. a malaria-mosquito model has been used to test this concept by making a comparison of the fitness of highly susceptible lines of mosquitoes with lines that are resistant to infection. malaria infection is known to cause a decrease in fecundity and fertility of mosquitoes; resistant mosquitoes were thus predicted to be fitter th ... | 2005 | 16526504 |
| isolation of a new strain of the flavivirus cell fusing agent virus in a natural mosquito population from puerto rico. | the genus flavivirus contains approximately 70 single-stranded, positive-sense rna viruses that are mosquito-borne, tick-borne or have no known vector. two discoveries support previous suggestions of the existence of a large number of unsampled flaviviruses: (i) a new flavivirus, kamiti river virus, was recently isolated from kenyan mosquitoes, and (ii) sequences with high similarity to those of flaviviruses have been found integrated into the genome of aedes mosquitoes, suggesting a past infect ... | 2006 | 16528021 |
| engineering rna interference-based resistance to dengue virus type 2 in genetically modified aedes aegypti. | mosquitoes (aedes aegypti) were genetically modified to exhibit impaired vector competence for dengue type 2 viruses (denv-2). we exploited the natural antiviral rna interference (rnai) pathway in the mosquito midgut by constructing an effector gene that expresses an inverted-repeat (ir) rna derived from the premembrane protein coding region of the denv-2 rna genome. the a. aegypti carboxypeptidase a promoter was used to express the ir rna in midgut epithelial cells after ingestion of a bloodmea ... | 2006 | 16537508 |
| comparative salivary gland transcriptomics of sandfly vectors of visceral leishmaniasis. | immune responses to sandfly saliva have been shown to protect animals against leishmania infection. yet very little is known about the molecular characteristics of salivary proteins from different sandflies, particularly from vectors transmitting visceral leishmaniasis, the fatal form of the disease. further knowledge of the repertoire of these salivary proteins will give us insights into the molecular evolution of these proteins and will help us select relevant antigens for the development of a ... | 2006 | 16539713 |
| cytokine profiles of filarial granulomas in jirds infected with brugia pahangi. | a granulomatous inflammatory response develops in jirds infected subcutaneously or intraperitoneally with filarial nematodes namely brugia pahangi and b. malayi. previous studies by light and electron microscopy have shown cellular inflammatory responses in and around these granulomas. furthermore, the cellular inflammatory responses of granulomas found in the lymphatics and peritoneal cavity appear to be similar. the purpose of this study was to determine the cytokine profiles of granulomas in ... | 2006 | 16542426 |
| comparative genomics of insect juvenile hormone biosynthesis. | the biosynthesis of insect juvenile hormone (jh) and its neuroendocrine control are attractive targets for chemical control of insect pests and vectors of disease. to facilitate the molecular study of jh biosynthesis, we analyzed ests from the glands producing jh, the corpora allata (ca) in the cockroach diploptera punctata, an insect long used as a physiological model species and compared them with ests from the ca of the mosquitoes aedes aegypti and anopheles albimanus. the predicted genes wer ... | 2006 | 16551550 |
| inflammatory responses to migrating brugia pahangi third-stage larvae. | despite being central to parasite establishment and subsequent host pathological and immunologic responses, host-parasite interactions during early third-stage filarial larva (l3) migration are poorly understood. these studies aimed to define early tissue migration of brugia pahangi l3 in the gerbil (meriones unguiculatus) and measure host cellular responses during this period. gerbils were intradermally inoculated in the hind limb with 100 b. pahangi l3, and necropsies were performed at various ... | 2006 | 16552066 |
| development of a live attenuated dengue virus vaccine using reverse genetics. | there are four serotypes of dengue (den1-den4) virus that are endemic in most areas of southeast asia, central and south america, and other subtropical regions. the number of cases of severe disease associated with den virus infection is growing because of the continued spread of the mosquito vector, aedes aegypti, which transmits the virus to humans. infection with den virus can result in an asymptomatic infection, a febrile illness called dengue fever (df), and the very severe disease called d ... | 2006 | 16553547 |
| early determination of the reproductive number for vector-borne diseases: the case of dengue in brazil. | to evaluate a new method of deriving the reproductive number for vector-borne diseases from the early epidemic curves for vector-borne diseases with incubations in the vectors and in the hosts. | 2006 | 16553913 |
| the distribution of hatching time in anopheles gambiae. | knowledge of the ecological differences between the molecular forms of anopheles gambiae and their sibling species, an. arabiensis might lead to understanding their unique contribution to disease transmission and to better vector control as well as to understanding the evolutionary forces that have separated them. | 2006 | 16553960 |
| [community participation in dengue prevention: an approach from the perspective of different social actors]. | to explore the perceptions about community participation in dengue fever control during formative research for a community project. | 2006 | 16555533 |
| spatial variability in the density, distribution and vectorial capacity of anopheline species in a high transmission village (equatorial guinea). | malaria transmission varies from one country to another and there are also local differences in time and space. an important variable when explaining the variability in transmission is the breeding behaviour of the different vector species and the availability of breeding sites. the aim of this study was to determine the geographical variability of certain entomological parameters: human biting rate (hbr), sporozoitic index (si) for plasmodium falciparum and entomological inoculation rate (eir). | 2006 | 16556321 |
| using green fluorescent malaria parasites to screen for permissive vector mosquitoes. | the plasmodium species that infect rodents, particularly plasmodium berghei and plasmodium yoelii, are useful to investigate host-parasite interactions. the mosquito species that act as vectors of human plasmodia in south east asia, africa and south america show different susceptibilities to infection by rodent plasmodium species. p. berghei and p. yoelii infect both anopheles gambiae and anopheles stephensi, which are found mainly in africa and asia, respectively. however, it was reported that ... | 2006 | 16569221 |
| mosquito vector control and biology in latin america--a 15th symposium. abstracts. | the 15th annual latin american symposium presented by the american mosquito control association (amca) was held as part of the 71st annual meeting in vancouver, british columbia, canada, in april 2005. the principal objective, as for the previous 14 symposia, was to promote participation in the amca by vector control specialists, public health workers, and academicians from latin america. this publication includes summaries of 40 presentations that were given orally in spanish or presented as po ... | 2005 | 16570381 |
| colonization of aedes aegypti midgut by the endosymbiont-bearing trypanosomatid blastocrithidia culicis. | monoxenous trypanosomatids inhabit invertebrate hosts throughout their life cycle. however, there have been cases of hiv-positive patients who have presented opportunistic infections caused by these protozoa, offering new perspectives to the study of interactions between monoxenics and hematophagous insect vectors. some monoxenous trypanosomatids present a symbiotic bacterium in the cytoplasm, which seems to promote biochemical and morphological changes in the host trypanosomatids, such as alter ... | 2006 | 16572337 |
| antennal sensilla of two female anopheline sibling species with differing host ranges. | volatile odors are important sensory inputs that shape the behaviour of insects, including agricultural pests and disease vectors. anopheles gambiae s.s. is a highly anthropophilic mosquito and is the major vector for human malaria in sub-sahara africa, while anopheles quadriannulatus, largely due to its zoophilic behaviour, is considered a non-vector species in the same region. careful studies of olfaction in these sibling species may lead to insights about the mechanisms that drive host prefer ... | 2006 | 16573828 |
| do herbicide treatments reduce the sensitivity of mosquito larvae to insecticides? | invasive mosquitoes are economic and sanitary concerns especially in europe and america. most work has emphasized the role of resistance [berrada, s., fournier, d., cuany, a., nguyen, t.x., 1994. identification of resistance mechanisms in a selected laboratory strain of cacopsylla pyri (homoptera: psyllidae): altered acetylcholinesterases and detoxifying oxidases. pesticide biochemistry and physiology 48, 41-47; hemingway, j., hawkes, n.j., mccarroll, l., ranson, h., 2004. the molecular basis of ... | 2006 | 16574189 |
| crystal structure of the anopheles gambiae 3-hydroxykynurenine transaminase. | in anopheles gambiae, the vector for the most deadly malaria parasite plasmodium falciparum, xanthurenic acid (xa) plays a key role in parasite gametogenesis and fertility. in mosquitoes, xa is produced by transamination of 3-hydroxykynurenine (3-hk), a reaction that represents the main route to prevent the accumulation of the potentially toxic 3-hk excess. interfering with xa metabolism in a. gambiae therefore appears an attractive avenue for the development of malaria transmission-blocking dru ... | 2006 | 16585514 |
| evaluation of the present dengue situation and control strategies against aedes aegypti in cebu city, philippines. | the present dengue situation and methods to control aedes aegypti larvae in cebu city, philippines, were evaluated for the development of an integrated community-based dengue control program. the study included the detection of dengue infection among filipino patients, surveying mosquito breeding sites to determine larval population density of aedes aegypti, an evaluation of public knowledge, attitude, and personal protection practices against dengue, and an evaluation of the efficacy of vectoba ... | 2005 | 16599163 |
| chemical composition and anti-mosquito potential of rhizome extract and volatile oil derived from curcuma aromatica against aedes aegypti (diptera: culicidae). | crude rhizome extracts and volatile oils of curcuma aromatica were evaluated for chemical composition and anti-mosquito potential, including larvicidal, adulticidal, and repellent activities against the aedes aegypti mosquito. chemical identification achieved by gc/ms analysis revealed that xanthorrhizol, 1h-3a, 7-methanoazulene and curcumene at 35.08 and 13.65%, 21.81 and 30.02%, and 13.75 and 25.71%, were the main constituents in hexane extracts and volatile oils, respectively. volatile oil of ... | 2005 | 16599168 |
| the use of an experimental hut for evaluating the entering and exiting behavior of aedes aegypti (diptera: culicidae), a primary vector of dengue in thailand. | | 2005 | 16599177 |
| determinants of vector specificity of o'nyong nyong and chikungunya viruses in anopheles and aedes mosquitoes. | the alphaviruses o'nyong nyong virus (onnv) and chikungunya virus (chikv) provide a unique system to study the viral genes involved in vector specificity. onnv infects both anopheline and culicine mosquitoes, whereas chikv infects only culicine mosquitoes. in this study, chimeric viruses were constructed that contained genes from both onnv and chikv. these chimeras and previously described full-length infectious clones of onnv and chikv were evaluated in anopheles gambiae and aedes aegypti mosqu ... | 2006 | 16607002 |
| human and mosquito infections by dengue viruses during and after epidemics in a dengue-endemic region of colombia. | we conducted a study in a dengue-endemic area of colombia to evaluate the dynamics of transmission of dengue viruses during and after epidemics. information was simultaneously gathered about occurrence of infection in humans and mosquitoes every three months in four cities with endemic transmission. viral isolation was confirmed in 6.7% of the persons and most were asymptomatic. adult mosquito and larvae house indexes were not found associated with increased burden of disease. the only entomolog ... | 2006 | 16607005 |
| dengue knowledge and practices and their impact on aedes aegypti populations in kamphaeng phet, thailand. | a knowledge, attitude, and practice (kap) survey and an extensive entomologic survey were conducted in two sub-districts of kamphaeng phet province, thailand, to test the hypothesis that correct dengue knowledge and practice reduce dengue vector populations. we found a negative association between respondents' knowledge of preventive measures and the number of unprotected containers in and around their houses. knowledge of development sites was positively associated with unprotected containers. ... | 2006 | 16607007 |
| superior reproductive success on human blood without sugar is not limited to highly anthropophilic mosquito species. | anthropophilic mosquitoes such as aedes aegypti l. (diptera: culicidae) have been shown to have superior reproductive success on human blood when sugar is not available. life-table experiments were conducted with aedes albopictus skuse and ae. aegypti to compare the effects of sugar availability on age-specific survivorship, lifetime and daily fecundity, and blood-feeding frequency when offered human blood daily. there were no significant interactions between the effects of sugar availability an ... | 2006 | 16608490 |
| screening for larvicidal activity in some thai plants against four mosquito vector species. | ninety-six ethanolic extracts from various parts of 84 thai plant species were tested for their larvicidal activity against aedes aegypti mosquitoes. extracts from rhinacanthus nasutus, derris elliptica, trigonostemon reidioides, homalomena aromatica, stemona tuberosa and acorus calamus possessed high larvicidal activity, with lc50 values between 16.0 and 48.2 mg/l. petroleum ether (pe) and methanol (meoh) extracts were tested for their larvicidal activity against 4 mosquito vector species. the ... | 2005 | 16610643 |
| characteristics of grass infusions as oviposition attractants to aedes (stegomyia) (diptera: culicidae). | ovitraps baited with grass infusions were evaluated in the field as oviposition attractants or stimulants for aedes (stegomyia) mosquitoes. significantly higher oviposition by aedes aegypti (l.) was observed in areas with no vegetation, but intense human presence, whereas aedes albopictus (skuse) oviposition was significantly higher in areas with vegetation, regardless of human presence. ovitraps baited with infusions of panicum maximum (jacq.) collected significantly more eggs than controls con ... | 2006 | 16619601 |
| laboratory evaluation of avian odors for mosquito (diptera: culicidae) attraction. | attraction of culex quinquefasciatus say, culex tarsalis coquillett, culex nigripalpus theobald, and aedes aegypti (l.) to avian and other host odors was investigated in a dual-port olfactometer. although attraction to a human arm was high for ae. aegypti (>80%) and low for all culex spp. (<25%), all species responded similarly to a chicken (55.3-73.6%). responses of ae. aegypti, cx. quinquefasciatus, and cx. nigripalpus to feathers were low (<20%) but greater than to controls. there was no diff ... | 2006 | 16619603 |