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genes and odors underlying the recent evolution of mosquito preference for humans.mosquito species that specialize in biting humans are few but dangerous. they include the african malaria vectors anopheles gambiae and anopheles coluzzii, as well as aedes aegypti, the cosmopolitan vector of dengue, chikungunya, and yellow fever. these mosquitoes have evolved a remarkable innate preference for human odor that helps them find and bite us. here i review what is known about this important evolutionary adaptation, from its historical documentation to its chemical and molecular basi ...026766234
larval competition between aedes japonicus and aedes atropalpus (diptera: culicidae) in simulated rock pools.the success of an invasive species becoming established in a new region often depends on its interactions with ecologically similar resident species. the propensity of the newly-established mosquito aedes japonicus to inhabit rock pools throughout the eastern united states provides a natural setting for interspecific larval competition with the native aedes atropalpus. a laboratory experiment conducted in simulated rock pools to evaluate larval interactions between and within these two species s ...019263842
acoustic communication in insect disease vectors.acoustic signalling has been extensively studied in insect species, which has led to a better understanding of sexual communication, sexual selection and modes of speciation. the significance of acoustic signals for a blood-sucking insect was first reported in the xix century by christopher johnston, studying the hearing organs of mosquitoes, but has received relatively little attention in other disease vectors until recently. acoustic signals are often associated with mating behaviour and sexua ...024473800
identification and molecular characterization of a prophenoloxidase involved in aedes aegypti chorion melanization.chorion melanization is a vital biochemical event for the survival of mosquito eggs in the environment. this study describes the identification and molecular characterization of a prophenoloxidase (propo) involved in chorion melanization in aedes aegypti by various biochemical and molecular techniques. results revealed that transcription of the chorion propo occurs only in adults, blood feeding greatly stimulated its transcription and haemocytes are responsible for its transcription. our study p ...015796752
effects of elevated atmospheric co(2) on water chemistry and mosquito (diptera: culicidae) growth under competitive conditions in container habitats.we investigated the direct and indirect effects of elevated atmospheric co(2) on freshwater container habitats and their larval mosquito occupants. we predicted that a doubling of atmospheric co(2) would (1) alter the chemical properties of water in this system, (2) slow degradation of leaf litter, and (3) decrease larval growth of aedes albopictus (skuse) mosquitoes raised on that litter under competitive conditions. effects of elevated co(2) on water quality parameters were not detected, but t ...022661767
description of the transcriptomes of immune response-activated hemocytes from the mosquito vectors aedes aegypti and armigeres subalbatus.mosquito-borne diseases, including dengue, malaria, and lymphatic filariasis, exact a devastating toll on global health and economics, killing or debilitating millions every year (54). mosquito innate immune responses are at the forefront of concerted research efforts aimed at defining potential target genes that could be manipulated to engineer pathogen resistance in vector populations. we aimed to describe the pivotal role that circulating blood cells (called hemocytes) play in immunity by gen ...015213157
filariasis of uncommon nature in india. 023509678
intron retention in the drosophila melanogaster rieske iron sulphur protein gene generated a new protein.genomes can encode a variety of proteins with unrelated architectures and activities. it is known that protein-coding genes of de novo origin have significantly contributed to this diversity. however, the molecular mechanisms and evolutionary processes behind these originations are still poorly understood. here we show that the last 102 codons of a novel gene, noble, assembled directly from non-coding dna following an intronic deletion that induced alternative intron retention at the drosophila ...021610726
mosquito hemocyte-mediated immune responses.hemocytes are a key component of the mosquito immune system that kill pathogens via phagocytic, lytic and melanization pathways. individual mosquitoes contain between 500 and 4,000 hemocytes, which are divided into three populations named granulocytes, oenocytoids and prohemocytes. hemocytes can also be divided by their anatomical location with 75% of hemocytes circulating in the hemocoel (circulating hemocytes) and 25% of hemocytes attaching themselves to tissues (sessile hemocytes). greater th ...025309850
design and testing of a novel, protective human-baited tent trap for the collection of anthropophilic disease vectors.currently, there exists a deficit of safe, active trapping methods for the collection of host-seeking anopheles and other disease-causing arthropod vectors. the gold-standard approach for mosquito collection is that of human landing catch (hlc), in which an individual exposes bare skin to possibly infected vectors. here, we present the development of a new method for mosquito collection, the infoscitex tent, which uses modern tent materials coupled with a novel trap design. this provides an effi ...024605476
diversity and convergence of sodium channel mutations involved in resistance to pyrethroids.pyrethroid insecticides target voltage-gated sodium channels, which are critical for electrical signaling in the nervous system. the intensive use of pyrethroids in controlling arthropod pests and disease vectors has led to many instances of pyrethroid resistance around the globe. in the past two decades, studies have identified a large number of sodium channel mutations that are associated with resistance to pyrethroids. the purpose of this review is to summarize both common and unique sodium c ...024019556
resistance of aedes aegypti to temephos and adaptive disadvantages.to evaluate the resistance of aedes aegypti to temephos fersol 1g (temephos 1% w/w) associated with the adaptive disadvantage of insect populations in the absence of selection pressure.025372168
o'nyong-nyong virus infection imported to europe from kenya by a traveler. 025271361
dengue expansion in africa-not recognized or not happening?an expert conference on dengue in africa was held in accra, ghana, in february 2013 to consider key questions regarding the possible expansion of dengue in africa. four key action points were highlighted to advance our understanding of the epidemiology of dengue in africa. first, dengue diagnostic tools must be made more widely available in the healthcare setting in africa. second, representative data need to be collected across africa to uncover the true burden of dengue. third, established net ...025271370
effects of pygidial secretion (zoopesticide) on histopathological changes in the male accessory reproductive glands of adult male insect odontopus varicornis in relation to reproduction.indiscriminate use of pesticides for the eradication of pests causes tremendous changes to the environment and also to other nontarget organisms. to prevent such contamination of the environment and save nontarget species, zoopesticides are increasingly used as they are cost effective, eco-friendly, safe, and sustainable in the field of agriculture. the present study was undertaken to find out the effect of pygidial secretion (zoopesticide) on odontopus varicornis. the insects were exposed to py ...021042469
functional consequences of mutations in the drosophila histamine receptor hclb.the gene hclb encodes a histamine-gated chloride channel subunit in drosophila melanogaster. mutations in hclb lead to defects in the visual system and altered sensitivity to the action of ivermectin. to investigate whether this member of the cys-loop receptors is common across the insecta, we analysed the genomes of seven other insect species (diptera, hymenoptera, coleoptera) and revealed orthologues of hclb in all of them. sequence comparisons showed high identity levels between the orthologu ...019716373
the epidemiology of dengue in the americas over the last three decades: a worrisome reality.we have reported the epidemic patterns of dengue disease in the region of the americas from 1980 through 2007. dengue cases reported to the pan american health organization were analyzed from three periods: 1980-1989 (80s), 1990-1999 (90s), and 2000-2007 (2000-7). age distribution data were examined from brazil, venezuela, honduras, and mexico. cases increased over time: 1,033,417 (80s) to 2,725,405 (90s) to 4,759,007 (2000-7). the highest concentrations were reported in the hispanic caribbean ( ...020065008
eco-bio-social determinants of dengue vector breeding: a multicountry study in urban and periurban asia.to study dengue vector breeding patterns under a variety of conditions in public and private spaces; to explore the ecological, biological and social (eco-bio-social) factors involved in vector breeding and viral transmission, and to define the main implications for vector control.020428384
chromatin-remodelling proteins of the pea aphid, acyrthosiphon pisum (harris).aphids display extraordinary developmental plasticity in response to environmental cues. these differential responses to environmental changes may be due in part to changes in gene expression patterns. to understand the molecular basis for aphid developmental plasticity, we attempted to identify the chromatin-remodelling machinery in the recently sequenced pea aphid genome. we find that the pea aphid possesses a complement of metazoan histone modifying enzymes with greater gene family diversity ...020482651
alkaline phosphatase from venom of the endoparasitoid wasp, pteromalus puparum.using chromogenic substrates 5-bromo-4-chloro-3'-indolyl phosphate and nitro blue tetrazolium, alkaline phosphatase (alpase) was histochemically detected in the venom apparatus of an endoparasitoid wasp, pteromalus puparum l. (hymenoptera: pteromalidae). ultrastructural observations demonstrated its presence in the secretory vesicles and nuclei of the venom gland secretory cells. using p-nitrophenyl phosphate as substrate to measure enzyme activity, the venom alpase was found to be temperature d ...020575745
dengue spatial and temporal patterns, french guiana, 2001.to study a 2001 dengue fever outbreak in iracoubo, french guiana, we recorded the location of all patients' homes and the date when symptoms were first observed. a geographic information system (gis) was used to integrate the patient-related information. the knox test, a classic space-time analysis technique, was used to detect spatiotemporal clustering. analysis of the relative-risk (rr) variations when space and time distances vary, highlighted the maximum space and time extent of a dengue tra ...015200850
dengue fever outbreak in a recreation club, dhaka, bangladesh.an outbreak of dengue fever occurred among employees of a recreation club in bangladesh. occupational transmission was characterized by a 12% attack rate, no dengue among family contacts, and aedes vectors in club areas. early recognition of the outbreak likely limited its impact.015200876
signature of the oligomeric behaviour of nuclear receptors at the sequence and structural level.nuclear receptors (nrs) are ligand-dependent transcription factors that control a large number of physiological events through the regulation of gene transcription. nrs function either as homodimers or as heterodimers with retinoid x receptor/ultraspiracle protein (rxr/usp). a structure-based sequence analysis aimed at discovering the molecular mechanism that controls the dimeric association of the ligand-binding domain reveals two sets of differentially conserved residues, which partition the e ...015105832
stereodivergent construction of cyclic ethers by a regioselective and enantiospecific rhodium-catalyzed allylic etherification: total synthesis of gaur acid. 015366088
interspecific differences in feeding behavior and survival under food-limited conditions for larval aedes albopictus and aedes aegypti (diptera: culicidae).aedes albopictus has replaced aedes aegypti in much of the latter species' historic range within the united states. the leading hypothesis for this displacement is exclusion via resource competition; however, the proximate mechanism producing a competitive advantage for a. albopictus over a. aegypti has not been identified. we performed laboratory experiments to test the hypotheses that these species differ in feeding behavior, and that these differences result in differences in survival when re ...023197877
yellow fever: readily prevented but difficult to treat. 015210636
concurrent malaria and dengue fever: a need for rapid diagnostic methods.malaria and dengue fever are endemic in the south-east asian region including india. both the illnesses share similar symptomatology, but differ in certain respects such as different- causative organisms and mosquito vector with diverse habitat. hence, concurrent malaria and dengue fever in the same patient is said to be unusual. there have been cases of concurrent malaria and dengue, but they are scarce from highly endemic region like ours. here, we describe three unusual cases of plasmodium vi ...025657963
functional characterizations of residues arg-158 and tyr-170 of the mosquito-larvicidal bacillus thuringiensis cry4ba.the insecticidal activity of bacillus thuringiensis (bt) cry toxins involves toxin stabilization, oligomerization, passage across the peritrophic membrane (pm), binding to midgut receptors and pore-formation. the residues arg-158 and tyr-170 have been shown to be crucial for the toxicity of bt cry4ba. we characterized the biological function of these residues. in mosquito larvae, the mutants r158a/e/q (r158) could hardly penetrate the pm due to a significantly reduced ability to alter pm permeab ...024286331
an unusual ocular emergency in severe dengue.dengue, one of the most common mosquito-borne flavivirus diseases affecting humans, is spread by the aedes aegypti mosquito. most people infected with dengue virus are asymptomatic or only have mild symptoms such as an uncomplicated fever; few have more severe features, while in a small proportion it is life-threatening. severe dengue is defined as that associated with severe bleeding, severe organ dysfunction, or severe plasma leakage. ophthalmic manifestations can involve both the anterior and ...025371643
three-way interactions between mosquito population, viral strain and temperature underlying chikungunya virus transmission potential.interactions between pathogens and their insect vectors in nature are under the control of both genetic and non-genetic factors, yet most studies on mosquito vector competence for human pathogens are conducted in laboratory systems that do not consider genetic and/or environmental variability. evaluating the risk of emergence of arthropod-borne viruses (arboviruses) of public health importance such as chikungunya virus (chikv) requires a more realistic appraisal of genetic and environmental cont ...025122228
cellular mechanisms of acid secretion in the posterior midgut of the larval mosquito (aedes aegypti).the gut contents of larval mosquitoes are alkalinized by the anterior midgut and reacidified by the posterior midgut. in the present study the cellular mechanisms of reacidification were studied in isolated, perfused posterior midgut by measuring the transepithelial voltage (v(te)) and the rate of acid secretion as indicated by the color change of m-cresol purple during intervals of perfusion stop. the lumen-positive v(te) and reacidification were significantly increased by serotonin (0.2 mumol ...020038664
comparative analysis of nuclear trna genes of nasonia vitripennis and other arthropods, and relationships to codon usage bias.using bioinformatics methods, we identified a total of 221 and 199 trna genes in the nuclear genomes of nasonia vitripennis and honey bee (apis mellifera), respectively. we performed comparative analyses of nasonia trna genes with honey bee and other selected insects to understand genomic distribution, sequence evolution and relationship of trna copy number with codon usage patterns. many trna genes are located physically close to each other in the form of small clusters in the nasonia genome. h ...020167017
chikungunya fever in traveler from angola to japan, 2016.simultaneous circulation of multiple arboviruses presents diagnostic challenges. in may 2016, chikungunya fever was diagnosed in a traveler from angola to japan. travel history, incubation period, and phylogenetic analysis indicated probable infection acquisition in angola, where a yellow fever outbreak is ongoing. thus, local transmission of chikungunya virus probably also occurs in angola.027983938
biosynthetic pathway of insect juvenile hormone iii in cell suspension cultures of the sedge cyperus iria.in most insect species, juvenile hormones regulate critical physiological processes such as metamorphosis and reproduction. in insects, these sesquiterpenoids are synthesized by retrocerebral endocrine organs, the corpora allata, via the classical mevalonate (mva) pathway. one of these compounds, juvenile hormone iii (jh iii), has also been identified in the sedge cyperus iria. in higher plants, biosynthesis of the sesquiterpenoid backbone may proceed through two distinct pathways: the mva pathw ...011598232
vector-borne diseases and global warming: are both on an upward swing? scientists are still debating whether global warming will lead to a further spread of mosquitoes and the diseases they transmit. 011559583
from genome to "venome": molecular origin and evolution of the snake venom proteome inferred from phylogenetic analysis of toxin sequences and related body proteins.this study analyzed the origin and evolution of snake venom proteome by means of phylogenetic analysis of the amino acid sequences of the toxins and related nonvenom proteins. the snake toxins were shown to have arisen from recruitment events of genes from within the following protein families: acetylcholinesterase, adam (disintegrin/metalloproteinase), avit, complement c3, crotasin/beta defensin, cystatin, endothelin, factor v, factor x, kallikrein, kunitz-type proteinase inhibitor, lynx/slur, ...015741511
the changing tails of a novel short interspersed element in aedes aegypti: genomic evidence for slippage retrotransposition and the relationship between 3' tandem repeats and the poly(da) tail.a novel family of trna-related sines named gecko was discovered in the yellow fever mosquito, aedes aegypti. approximately 7200 copies of gecko were distributed in the a. aegypti genome with a significant bias toward a + t-rich regions. the 3' end of gecko is similar in sequence and identical in secondary structure to the 3' end of mosqui, a non-ltr retrotransposon in a. aegypti. nine conserved substitutions and a deletion separate gecko into two groups. group i includes all gecko that end with ...015611173
bracoviruses contain a large multigene family coding for protein tyrosine phosphatases.the relationship between parasitic wasps and bracoviruses constitutes one of the few known mutualisms between viruses and eukaryotes. the virions produced in the wasp ovaries are injected into host lepidopteran larvae, where virus genes are expressed, allowing successful development of the parasite by inducing host immune suppression and developmental arrest. bracovirus-bearing wasps have a common phylogenetic origin, and contemporary bracoviruses are hypothesized to have been inherited by chrom ...015542661
cysteine and keto acids modulate mosquito kynurenine aminotransferase catalyzed kynurenic acid production.kynurenine aminotransferase (kat) catalyzes the formation of kynurenic acid (kyna), the natural antagonist of ionotropic glutamate receptors. this study tests potential substrates and assesses the effects of amino acids and keto acids on the activity of mosquito kat. various keto acids, when simultaneously present in the same reaction mixture, display a combined effect on kat catalyzed kyna production. moreover, methionine and glutamine show inhibitory effects on kat activity, while cysteine fun ...015556614
natively unfolded domains in endocytosis: hooks, lines and linkers.it is commonly assumed that a protein must adopt a tertiary structure to achieve its active native state and that regions of a protein that are devoid of alpha-helix or beta-sheet structures are functionally inert. although extended proline-rich regions are recognized as presenting binding motifs to, for example, src homology 2 (sh2) and sh3 domains, the idea persists that natively unfolded regions in functional proteins are simply 'spacers' between the folded domains. such a view has been chall ...015520805
reappearance of chikungunya, formerly called dengue, in the americas.after an absence of ≈200 years, chikungunya returned to the american tropics in 2013. the virus is maintained in a complex african zoonotic cycle but escapes into an urban cycle at 40- to 50-year intervals, causing global pandemics. in 1823, classical chikungunya, a viral exanthem in humans, occurred on zanzibar, and in 1827, it arrived in the caribbean and spread to north and south america. in zanzibar, the disease was known as kidenga pepo, swahili for a sudden cramp-like seizure caused by an ...025816211
climate change influences on global distributions of dengue and chikungunya virus vectors.numerous recent studies have illuminated global distributions of human cases of dengue and other mosquito-transmitted diseases, yet the potential distributions of key vector species have not been incorporated integrally into those mapping efforts. projections onto future conditions to illuminate potential distributional shifts in coming decades are similarly lacking, at least outside europe. this study examined the global potential distributions of aedes aegypti and aedes albopictus in relation ...025688023
dengue: recent past and future threats.this article explores four key questions about statistical models developed to describe the recent past and future of vector-borne diseases, with special emphasis on dengue: (1) how many variables should be used to make predictions about the future of vector-borne diseases? (2) is the spatial resolution of a climate dataset an important determinant of model accuracy? (3) does inclusion of the future distributions of vectors affect predictions of the futures of the diseases they transmit? (4) whi ...025688021
present and future projections of habitat suitability of the asian tiger mosquito, a vector of viral pathogens, from global climate simulation.climate change can influence the transmission of vector-borne diseases (vbds) through altering the habitat suitability of insect vectors. here we present global climate model simulations and evaluate the associated uncertainties in view of the main meteorological factors that may affect the distribution of the asian tiger mosquito (aedes albopictus), which can transmit pathogens that cause chikungunya, dengue fever, yellow fever and various encephalitides. using a general circulation model at 50 ...025688015
molecular evolution, structure, and function of peroxidasins.peroxidasins represent the subfamily 2 of the peroxidase-cyclooxygenase superfamily and are closely related to chordata peroxidases (subfamily 1) and peroxinectins (subfamily 3). they are multidomain proteins containing a heme peroxidase domain with high homology to human lactoperoxidase that mediates one- and two-electron oxidation reactions. additional domains of the secreted and glycosylated metalloproteins are type c-like immunoglobulin domains, typical leucine-rich repeats, as well as a von ...022976969
chikungunya outbreak in bueng kan province, thailand, 2013. 025061989
transfusion support in patients with dengue fever.dengue fever has emerged as a global public health problem in the recent decades. the clinical spectrum of the disease ranges from dengue fever to dengue hemorrhagic fever and dengue shock syndrome. the disease is characterized by increased capillary permeability, thrombocytopenia and coagulopathy. thrombocytopenia with hemorrhagic manifestations warrants platelet transfusions. there is lack of evidence-based guidelines for transfusion support in patients with dengue fever. this contributes to i ...025298950
laboratory evaluation of the development of aedes aegypti in two seasons: influence of different places and different densities.aedes aegypti is an important vector in brazil being the main vector of the dengue-fever. this paper employs survival curves to describe the time in days from larvae to adult forms of aedes aegypti raised, individually and collectively, and compares it during winter and spring when positioned inside and outside a laboratory. the study was conducted in são vicente, a coastal city in southeastern brazil. the lowest water temperature in winter and in spring was 20 °c and the highest was 26 °c in sp ...025229215
detection and characterization of wolbachia infection in silkworm.wolbachia naturally infects a wide variety of arthropods, where it plays important roles in host reproduction. it was previously reported that wolbachia did not infect silkworm. by means of pcr and sequencing we found in this study that wolbachia is indeed present in silkworm. phylogenetic analysis indicates that wolbachia infection in silkworm may have occurred via transfer from parasitic wasps. furthermore, southern blotting results suggest a lateral transfer of the wsp gene into the genomes o ...025249781
bacillus thuringiensis cry1a toxins are versatile proteins with multiple modes of action: two distinct pre-pores are involved in toxicity.cry proteins from bacillus thuringiensis are insecticidal pfts (pore-forming toxins). in the present study, we show that two distinct functional pre-pores of cry1ab are formed after binding of the protoxin or the protease-activated toxin to the cadherin receptor, but before membrane insertion. both pre-pores actively induce pore formation, although with different characteristics, and contribute to the insecticidal activity. we also analysed the oligomerization of the mutant cry1abmod protein. th ...024456341
clinical, virologic, and epidemiologic characteristics of dengue outbreak, dar es salaam, tanzania, 2014.we investigated a dengue outbreak in dar es salaam, tanzania, in 2014, that was caused by dengue virus (denv) serotype 2. denv infection was present in 101 (20.9%) of 483 patients. patient age and location of residence were associated with infection. seven (4.0%) of 176 patients were co-infected with malaria and denv.027088845
an operational framework for insecticide resistance management planning.arthropod vectors transmit organisms that cause many emerging and reemerging diseases, and their control is reliant mainly on the use of chemical insecticides. only a few classes of insecticides are available for public health use, and the increased spread of insecticide resistance is a major threat to sustainable disease control. the primary strategy for mitigating the detrimental effects of insecticide resistance is the development of an insecticide resistance management plan. however, few exa ...027089119
double trouble: combined action of meiotic drive and wolbachia feminization in eurema butterflies.arthropod sex ratios can be manipulated by a diverse range of selfish genetic elements, including maternally inherited wolbachia bacteria. feminization by wolbachia is rare but has been described for eurema mandarina butterflies. in this species, some phenotypic and functional females, thought to be zz genetic males, are infected with a feminizing wolbachia strain, wfem. meanwhile, heterogametic wz females are not infected with wfem. here, we establish a quantitative pcr assay allowing reliable ...025948567
chile confronts its environmental health future after 25 years of accelerated growth.chile has recently been reclassified by the world bank from an upper-middle-income country to a high-income country. there has been great progress in the last 20 to 30 years in relation to air and water pollution in chile. yet after 25 years of unrestrained growth, there remain clear challenges posed by air and water pollution, as well as climate change.026615070
chikungunya outbreak in garo hills, meghalaya: an epidemiological perspective.chikungunya (chik) fever is a mosquito-borne disease caused by chikungunya virus (chikv). chikungunya infection was first reported from india in 1963 from kolkata. we report the serological and molecular evidence of an outbreak of chikungunya in northeast india that occurred in tura, a hilly and forested terrain in garo hills district of meghalaya.026139776
how mathematical epidemiology became a field of biology: a commentary on anderson and may (1981) 'the population dynamics of microparasites and their invertebrate hosts'.we discuss the context, content and importance of the paper 'the population dynamics of microparasites and their invertebrate hosts', by r. m. anderson and r. m. may, published in the philosophical transactions of the royal society as a stand-alone issue in 1981. we do this from the broader perspective of the study of infectious disease dynamics, rather than the specific perspective of the dynamics of insect pathogens. we argue that their 1981 paper fits seamlessly in the systematic study of inf ...025750231
big data: the future of biocuration. 018769432
seasonality and the effectiveness of mass vaccination.many infectious diseases have seasonal outbreaks, which may be driven by cyclical environmental conditions (e.g., an annual rainy season) or human behavior (e.g., school calendars or seasonal migration). if a pathogen is only transmissible for a limited period of time each year, then seasonal outbreaks could infect fewer individuals than expected given the pathogen's in-season transmissibility. influenza, with its short serial interval and long season, probably spreads throughout a population un ...027105983
detection of all four dengue serotypes in aedes aegypti female mosquitoes collected in a rural area in colombia.the aedes aegypti vector for dengue virus (denv) has been reported in urban and periurban areas. the information about denv circulation in mosquitoes in colombian rural areas is limited, so we aimed to evaluate the presence of denv in ae. aegypti females caught in rural locations of two colombian municipalities, anapoima and la mesa. mosquitoes from 497 rural households in 44 different rural settlements were collected. pools of about 20 ae. aegypti females were processed for denv serotype detect ...027074252
molecular determinants of odorant receptor function in insects.the olfactory system of drosophila melanogaster provides a powerful model to study molecular and cellular mechanisms underlying function of a sensory system. in the 1970s siddiqi and colleagues pioneered the application of genetics to olfactory research and isolated several mutant drosophila with odorant-specific defects in olfactory behaviour, suggesting that odorants are detected differentially by the olfactory system. since then basic principles of olfactory system function and development ha ...025116610
spatiotemporal distribution of dengue vectors & identification of high risk zones in district sonitpur, assam, india.dengue is an arboviral disease of public health importance in many parts of india and recently many cases have been reported from northeastern india. aedes mosquitoes, which are the vectors of dengue, are widely prevalent in the region. a study was initiated in sonitpur district of assam to understand the spatiotemporal distribution and seasonal prevalence of dengue vectors and to identify the high risk zones.025297362
bioactivity of indigenous medicinal plants against the cotton whitefly, bemisia tabaci.forty-one methanol extracts of 28 indigenous medicinal plant species were tested for their insecticidal bioactivity against cotton whitefly, bemisia tabaci (gennadius) (hemiptera: aleyrodidae), adults and second nymphal instars under controlled conditions. this study is within a bioprospection context, in the form of utilizing local plant species as an alternative in sustainable agriculture development. eighteen and nine plant extracts caused a significant decrease in number of live adult and ny ...025204756
expression of a toll signaling regulator serpin in a mycoinsecticide for increased virulence.serpins are ubiquitously distributed serine protease inhibitors that covalently bind to target proteases to exert their activities. serpins regulate a wide range of activities, particularly those in which protease-mediated cascades are active. the drosophila melanogaster serpin spn43ac negatively controls the toll pathway that is activated in response to fungal infection. the entomopathogenic fungus beauveria bassiana offers an environmentally friendly alternative to chemical pesticides for inse ...024837378
differential behavioral responses to water-borne cues to predation in two container-dwelling mosquitoes.larvae of the mosquito toxorhynchites rutilus (coquillett) prey upon other container-dwelling insects, including larvae of aedes albopictus (skuse), which is native to asia but was introduced into the united states, and on the native tree hole mosquito ochlerotatus triseriatus (say). previous work has established that o. triseriatus adopts low-risk behaviors in the presence of predation risk from t. rutilus. it is unknown whether introduced a. albopictus show a similar response to this predator. ...017710216
the sublethal effects of the entomopathic fungus leptolegnia chapmanii on some biological parameters of the dengue vector aedes aegypti.the mosquito aedes aegypti (l.) (diptera: culicidae) is the primary vector of dengue in the americas. the use of chemical insecticides is recommended during outbreaks of dengue in order to reduce the number of adult mosquitoes; however, because ae. aegypti is highly synanthropic, the use of insecticides in densely populated areas is a dangerous practice. leptolegnia chapmanii seymour (straminipila: peronosporomycetes) is an entomopathogenic microorganism that has demonstrated marked pathogenicit ...023901823
functional classification and central nervous projections of olfactory receptor neurons housed in antennal trichoid sensilla of female yellow fever mosquitoes, aedes aegypti.mosquitoes are highly dependent on their olfactory system for, e.g. host location and identification of nectar-feeding and oviposition sites. odours are detected by olfactory receptor neurons (orns) housed in hair-shaped structures, sensilla, on the antennae and maxillary palps. in order to unravel the function of the olfactory system in the yellow fever vector, aedes aegypti, we performed single-sensillum recordings from trichoid sensilla on female antennae. these sensilla are divided into four ...017880395
an empirical test of the aggregation model of coexistence and consequences for competing container-dwelling mosquitoes.we investigated the aggregation model of coexistence as a potential mechanism explaining patterns of coexistence between container mosquitoes aedes albopictus and aedes aegypti in southern florida, usa. aedes aegypti coexists with the invasive a. albopictus in many locations despite being an inferior resource competitor under most conditions. in agreement with aggregation theory we observed significant intraspecific aggregation of a. albopictus in all six field sites sampled in southern florida ...023691666
predator identity and additive effects in a treehole community.multiple predator species can interact as well as strongly affect lower trophic levels, resulting in complex, nonadditive effects on prey populations and community structure. studies of aquatic systems have shown that interactive effects of predators on prey are not necessarily predictable from the direct effects of each species alone. to test for complex interactions, the individual and combined effects of a top and intermediate predator on larvae of native and invasive mosquito prey were exami ...016676542
does differential predation permit invasive and native mosquito larvae to coexist in florida?1. the hypothesis that selective predation on larvae of the invasive aedes albopictus (skuse) could account for its stable coexistence with the native mosquito species and inferior competitor ochlerotatus triseriatus (say) in florida treeholes and container systems was tested experimentally.2. functional responses of the two dipteran predators toxorhynchites rutilus (coquillett) and corethrella appendiculata (grabham) were evaluated separately for a. albopictus and o. triseriatus prey. both pred ...022532705
cloning of the heat shock protein 60 gene from the stem borer, chilo suppressalis, and analysis of expression characteristics under heat stress.heat shock protein 60 is an important chaperonin. in this paper, hsp60 of the stem borer, chilo suppressalis (walker) (lepidoptera: pyralidae), was cloned by rt-pcr and rapid amplification of cdna end (race) reactions. the full length cdna of hsp6 degrees consisted of 2142 bp, with an orf of 1719 bp, encoding 572 amino acid residues, with a 5'utr of 158 bp and a 3'utr of 265 bp. cluster analysis confirmed that the deduced amino acid sequence shared high identity with the reported sequences from ...020673188
vasa genes: emerging roles in the germ line and in multipotent cells.sexually reproducing metazoans establish a cell lineage during development that is ultimately dedicated to gamete production. work in a variety of animals suggests that a group of conserved molecular determinants act in this germ line maintenance and function. the most universal of these genes are vasa and vasa-like dead-box rna helicase genes. however, recent evidence indicates that vasa genes also function in other cell types, distinct from the germ line. here we evaluate our current understan ...020586054
the central role of mosquito cytochrome p450 cyp6zs in insecticide detoxification revealed by functional expression and structural modelling.the resistance of mosquitoes to chemical insecticides is threatening vector control programmes worldwide. cytochrome p450 monooxygenases (cyps) are known to play a major role in insecticide resistance, allowing resistant insects to metabolize insecticides at a higher rate. among them, members of the mosquito cyp6z subfamily, like aedes aegypti cyp6z8 and its anopheles gambiae orthologue cyp6z2, have been frequently associated with pyrethroid resistance. however, their role in the pyrethroid degr ...023844938
multimodal integration of carbon dioxide and other sensory cues drives mosquito attraction to humans.multiple sensory cues emanating from humans are thought to guide blood-feeding female mosquitoes to a host. to determine the relative contribution of carbon dioxide (co2) detection to mosquito host-seeking behavior, we mutated the aaeggr3 gene, a subunit of the heteromeric co2 receptor in aedes aegypti mosquitoes. gr3 mutants lack electrophysiological and behavioral responses to co2. these mutants also fail to show co2-evoked responses to heat and lactic acid, a human-derived attractant, suggest ...024581501
nutrition-dependent control of insect development by insulin-like peptides.in metazoans, members of the insulin-like peptide (ilp) family play a role in multiple physiological functions in response to the nutritional status. ilps have been identified and characterized in a wide variety of insect species. insect ilps that are mainly produced by several pairs of medial neurosecretory cells in the brain circulate in the hemolymph and act systemically on target tissues. physiological and biochemical studies in lepidoptera and genetic studies in the fruit fly have greatly e ...026664828
cloning, expression analysis, and molecular modeling of the gamma-aminobutyric acid receptor alpha2 subunit gene from the common cutworm, spodoptera litura.intensive research on the molecule structures of the gamma-nminobutyric acid (gaba) receptor in agricultural pests has great significance to the mechanism investigation, resistance prevention, and molecular design of novel pesticides. the gaba receptor a2 (slgabarα2) subunit gene in spodoptera litura (fabricius) (lepidoptera: noctuidae) was cloned using the technologies of reverse transcription pcr and rapid amplification of cdna ends. the gemonic dna sequence of slgabarα2 has 5164 bp with 8 exo ...023909412
towards abolition of immunogenic structures in insect cells: characterization of a honey-bee (apis mellifera) multi-gene family reveals both an allergy-related core alpha1,3-fucosyltransferase and the first insect lewis-histo-blood-group-related antigen-synthesizing enzyme.glycoproteins from honey-bee (apis mellifera), such as phospholipase a2 and hyaluronidase, are well-known major bee-venom allergens. they carry n-linked oligosaccharide structures with two types of alpha1,3-fucosylation: the modification by alpha1,3-fucose of the innermost core glcnac, which constitutes an epitope recognized by ige from some bee-venom-allergic patients, and an antennal lewis-like galnacbeta1,4(fucalpha1,3)glcnac moiety. we now report the cloning and expression of two cdnas encod ...017029591
comparative genomics of odorant binding proteins in anopheles gambiae, aedes aegypti, and culex quinquefasciatus.about 1 million people in the world die each year from diseases spread by mosquitoes, and understanding the mechanism of host identification by the mosquitoes through olfaction is at stake. the role of odorant binding proteins (obps) in the primary molecular events of olfaction in mosquitoes is becoming an important focus of biological research in this area. here, we present a comprehensive comparative genomics study of obps in the three disease-transmitting mosquito species anopheles gambiae, a ...023292137
molecular determinants of differential ligand sensitivities of insect ecdysteroid receptors.the functional receptor for insect ecdysteroid hormones is a heterodimer consisting of two nuclear hormone receptors, ecdysteroid receptor (ecr) and the retinoid x receptor homologue ultraspiracle (usp). although ecdysone is commonly thought to be a hormone precursor and 20-hydroxyecdysone (20e), the physiologically active steroid, little is known about the relative activity of ecdysteroids in various arthropods. as a step toward characterization of potential differential ligand recognition, we ...010805730
but2 is a member of the third major group of hat transposons and is involved in horizontal transfer events in the genus drosophila.the hat superfamily comprises a large and diverse array of dna transposons found in all supergroups of eukaryotes. here we characterized the drosophila buzzatii but2 element and found that it harbors a five-exon gene encoding a 643-aa putatively functional transposase. a phylogeny built with 85 hat transposases yielded, in addition to the two major groups already described, ac and buster, a third one comprising 20 sequences that includes but2, tip100, hat-4_bm, and rp-hat1. this third group is h ...024459285
cloning and immunoreactivity of the 5-ht 1mac and 5-ht 2mac receptors in the central nervous system of the freshwater prawn macrobrachium rosenbergii.biogenic amines are implicated in several mental disorders, many of which involve social interactions. simple model systems, such as crustaceans, are often more amenable than vertebrates for studying mechanisms underlying behaviors. although various cellular responses of biogenic amines have been characterized in crustaceans, the mechanisms linking these molecules to behavior remain largely unknown. observed effects of serotonin receptor agonists and antagonists in abdomen posture, escape respon ...019184976
proteome changes in the plasma of papilio xuthus (lepidoptera: papilionidae): effect of parasitization by the endoparasitic wasp pteromalus puparum (hymenoptera: pteromalidae).although the biochemical dissection of parasitoid-host interactions is becoming well characterized, the molecular knowledge concerning them is minimal. in order to understand the molecular bases of the host immune response to parasitoid attack, we explored the response of papilio xuthus parasitized by the endoparasitic wasp pteromalus puparum using proteomic approach. by examining the differential expression of plasma proteins in the parasitized and unparasitized host pupae by two-dimensional (2 ...019489110
foreword. 024473796
cloning and sequence analysis of chitin synthase gene fragments of demodex mites.to our knowledge, few reports on demodex studied at the molecular level are available at present. in this study our group, for the first time, cloned, sequenced and analyzed the chitin synthase (chs) gene fragments of demodex folliculorum, demodex brevis, and demodex canis (three isolates from each species) from xi'an china, by designing specific primers based on the only partial sequence of the chs gene of d. canis from japan, retrieved from genbank. results show that amplification was successf ...023024043
insights into the venom composition of the ectoparasitoid wasp nasonia vitripennis from bioinformatic and proteomic studies.with the nasonia vitripennis genome sequences available, we attempted to determine the proteins present in venom by two different approaches. first, we searched for the transcripts of venom proteins by a bioinformatic approach using amino acid sequences of known hymenopteran venom proteins. second, we performed proteomic analyses of crude n. vitripennis venom removed from the venom reservoir, implementing both an off-line two-dimensional liquid chromatography matrix-assisted laser desorption/ io ...020167014
mechanisms and dynamics of orphan gene emergence in insect genomes.orphan genes are defined as genes that lack detectable similarity to genes in other species and therefore no clear signals of common descent (i.e., homology) can be inferred. orphans are an enigmatic portion of the genome because their origin and function are mostly unknown and they typically make up 10% to 30% of all genes in a genome. several case studies demonstrated that orphans can contribute to lineage-specific adaptation. here, we study orphan genes by comparing 30 arthropod genomes, focu ...023348040
a visible dominant marker for insect transgenesis.transgenesis of most insects currently relies on fluorescence markers. here we establish a transformation marker system causing phenotypes visible to the naked eye due to changes in the color of melanin pigments, which are widespread in animals. ubiquitous overexpression of arylalkylamine-n-acetyl transferase in the silkworm, bombyx mori, changes the color of newly hatched first-instar larvae from black to a distinctive light brown color, and can be used as a molecular marker by directly connect ...023250425
a mosquito sperm's journey from male ejaculate to egg: mechanisms, molecules, and methods for exploration.the fate of mosquito sperm in the female reproductive tract has been addressed sporadically and incompletely, resulting in significant gaps in our understanding of sperm-female interactions that ultimately lead to fertilization. as with other diptera, mosquito sperm have a complex journey to their ultimate destination, the egg. after copulation, sperm spend a short time at the site of insemination where they are hyperactivated and quickly congregate near the entrance of the spermathecal ducts. w ...027147424
inner workings: a big role for a microbial parasite. 027095842
sub-lethal metal stress response of larvae of aedes aegypti.aedes aegypti (diptera: culicidae) has adapted to urban environments; the urbanisation process provides suitable habitats for this disease vector subsequently increasing the probability of the transmission of pathogens in high-density environments. urban environments provide metal stressed larval habitats. however, little is known about the physiological cost of metal stress or how this might affect the performance of this mosquito species. this study aims to characterise the sub-lethal physiolo ...024926118
contribution of dengue fever to the burden of acute febrile illnesses in papua new guinea: an age-specific prospective study.malaria is a major contributor to the burden of febrile illnesses in papua new guinea (png). dengue fever (df) is likely to contribute; however, its epidemiology in png is poorly understood. we performed a prospective age-stratified study in outpatient clinics investigating the prevalence of df; 578 patients were enrolled, and 317 patients with a negative rapid diagnostic test (rdt) for malaria were tested for dengue. malaria was confirmed in 52% (301/578, 95% confidence interval [ci] = 48-56%), ...021734138
mosquitocidal properties of igg targeting the glutamate-gated chloride channel in three mosquito disease vectors (diptera: culicidae).the glutamate-gated chloride channel (glucl) is a highly sensitive insecticide target of the avermectin class of insecticides. as an alternative to using chemical insecticides to kill mosquitoes, we tested the effects of purified immunoglobulin g (igg) targeting the extracellular domain of glucl from anopheles gambiae (agglucl) on the survivorship of three key mosquito disease vectors: anopheles gambiae s.s., aedes aegypti and culex tarsalis. when administered through a single blood meal, anti-a ...025994632
diversity of wolbachia pipientis strain wpip in a genetically admixtured, above-ground culex pipiens (diptera: culicidae) population: association with form molestus ancestry and host selection patterns.analysis of molecular genetic diversity in nine marker regions of five genes within the bacteriophage wo genomic region revealed high diversity of the wolbachia pipentis strain wpip in a population of culex pipiens l. sampled in metropolitan chicago, il. from 166 blood fed females, 50 distinct genetic profiles of wpip were identified. rarefaction analysis suggested a maximum of 110 profiles out of a possible 512 predicted by combinations of the nine markers. a rank-abundance curve showed that fe ...022679853
effects of temperature on emergence and seasonality of west nile virus in california.temperature has played a critical role in the spatiotemporal dynamics of west nile virus transmission throughout california from its introduction in 2003 through establishment by 2009. we compared two novel mechanistic measures of transmission risk, the temperature-dependent ratio of virus extrinsic incubation period to the mosquito gonotrophic period (bt), and the fundamental reproductive ratio (r(0)) based on a mathematical model, to analyze spatiotemporal patterns of receptivity to viral ampl ...022556092
evaluation of carbon dioxide- and 1-octen-3-ol-baited centers for disease control fay-prince traps to collect aedes albopictus.during the summer of 2001, field studies were performed to evaluate the effects of carbon dioxide (co2) and 1-octen-3-ol (octenol) on the ability to collect aedes albopictus with centers for disease control (cdc) fay-prince traps. results from these studies indicated that ae. albopictus is significantly more attracted to co2- or co2 + octenol-baited cdc fay-prince traps than unbaited or octenol-baited traps. however, the difference between the responses to co2 and co2 + octenol was not statistic ...014710753
epidemic infections and their relevance to the gulf and other arabian peninsula countries. 024019727
preliminary analysis of several attractants and spatial repellents for the mosquito, aedes albopictus using an olfactometer.mosquito attractants and spatial repellents hold great promise in controlling mosquito pests. in assessing the effectiveness of mosquito attractants and repellents, a good olfactometer system, and optimized testing conditions, are essential. in this research, we demonstrated the usefulness of an olfactometer system, and optimized testing conditions for aedes albopictus (diptera: culicidae). we found no significant difference in the biting activity of the insect between 8:00 and 22:00. furthermor ...023418948
culex mosquitoes are experimentally unable to transmit zika virus.we report that two laboratory colonies of culex quinquefasciatus and culex pipiens mosquitoes were experimentally unable to transmit zikv either up to 21 days post an infectious blood meal or up to 14 days post intrathoracic inoculation. infectious viral particles were detected in bodies, heads or saliva by a plaque forming unit assay on vero cells. we therefore consider it unlikely that culex mosquitoes are involved in the rapid spread of zikv.027605159
experimental investigation of the susceptibility of italian culex pipiens mosquitoes to zika virus infection.we investigated the susceptibility of an italian population of culex pipiens mosquitoes to zika virus (zikv) infection, tested in parallel with aedes aegypti, as a positive control. we analysed mosquitoes at 0, 3, 7, 10, 14, 20 and 24 days after an infectious blood meal. viral rna was detected in the body of cx. pipiens up to three days post-infection, but not at later time points. our results indicate that cx. pipiens is not susceptible to zikv infection.027605056
zika in the united states: how are we preparing? 027581255
the mysterious zika virus: adding to the tropical flavivirus mayhem.until now, known as the demure cousin of dengue virus (denv) inhabiting africa, zika virus (zikv) has reinvented itself to cause explosive epidemics captivating the western hemisphere. the outbreak causing potential for zikv was realized when it made its way from africa to yap island micronesia in 2007, and in french polynesia in 2013. from there, it moved on to brazil in 2015. now zikv has infected people in more than 33 countries in central and south america and the caribbean. moreover the epi ...027763483
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