Publications

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the poly(a) polymerase gld2 is required for spermatogenesis in drosophila melanogaster.the dna of a developing sperm is normally inaccessible for transcription for part of spermatogenesis in many animals. in drosophila melanogaster, many transcripts needed for late spermatid differentiation are synthesized in pre-meiotic spermatocytes, but are not translated until later stages. thus, post-transcriptional control mechanisms are required to decouple transcription and translation during spermatogenesis. in the female germline, developing germ cells accomplish similar decoupling throu ...021427144
visceral leishmaniasis in far western nepal: another case and concerns about a new area of endemicity. 021363996
male mating history and body size influence female fecundity and longevity of the dengue vector aedes aegypti.male reproductive success is dependent on insemination success and reproductive output. during mating, male mosquitoes transfer not just sperm, but also seminal fluid proteins that may have profound effects on mated female biology and behavior. in this study, we investigated the role of male body size and mating history on semen depletion, female longevity, and reproductive success in aedes aegypti l. small and large males were mated in rapid succession with up to five females. our results indic ...021485355
proteome changes in the plasma of pieris rapae parasitized by the endoparasitoid wasp pteromalus puparum.parasitism by the endoparasitoid wasp pteromalus puparum causes alterations in the plasma proteins of pieris rapae. analysis of plasma proteins using a proteomic approach showed that seven proteins were differentially expressed in the host pupae after 24-h parasitism. they were masquerade-like serine proteinase homolog (msph), enolase (eno), bilin-binding protein (bbp), imaginal disc growth factor (idgf), ornithine decarboxylase (odc), cellular retinoic acid binding protein (crabp), and one unkn ...021265041
ecoepidemiologia del dengue: relevancia de dos vectores invasores. 025284912
characterization of cry2-type genes of bacillus thuringiensis strains from soilisolated of sichuan basin, china.sichuan basin, situated in the west of china, is the fourth biggest basin in china. in order to describe a systematic study of the cry2-type genes resources from bacillus thuringiensis strains of sichuan basin, a total of 791 bacillus thuringiensis strains have been screened from 2650 soil samples in different ecological regions. the method of pcr-restriction fragment length polymorphism (pcr-rflp) was used to identify the type of cry2 genes. the results showed that 322 bacillus thuringiensis st ...024031615
bilateral premacular subhyaloid hemorrhage in dengue fever. 022454709
sampling considerations for designing aedes aegypti (diptera:culicidae) oviposition studies in iquitos, peru: substrate preference, diurnal periodicity, and gonotrophic cycle length.when devising methods to sample aedes aegypti (l.) eggs from naturally-occurring containers to investigate selective oviposition, failure to take into account certain aspects of ae. aegypti behavior can bias study inferences. in iquitos, peru, we tested three assumptions related to designing ae. aegypti oviposition field studies, as follows: 1) lining containers with paper as an oviposition substrate does not affect oviposition; 2) diurnal egg-laying activity peaks in the late afternoon or early ...021337947
differential selection within the drosophila retinal determination network and evidence for functional divergence between paralog pairs.the retinal determination (rd) network in drosophila comprises 14 known nuclear proteins that include dna-binding proteins, transcriptional coactivators, kinases, and phosphatases. the composition of the network varies considerably throughout the animal kingdom, with the network in several basal insects having fewer members and with vertebrates having potentially significantly higher numbers of rd genes. one important contributing factor for the variation in gene number within the network is gen ...021210943
prevalence of chikungunya in urban field practice area of a private medical college, chennai.the outbreak of chikungunya in india started during december 2005 with more than 11,00,000 cases. many cases with symptoms suggestive of chikungunya reported to our urban health-training centre. hence this study was done to estimate the prevalence of chikungunya, to study the common treatment-seeking behavior, control measures and the sequalae of chikungunya by follow-up.021976797
discrete pulses of molting hormone, 20-hydroxyecdysone, during late larval development of drosophila melanogaster: correlations with changes in gene activity.periodic pulses of the insect steroid molting hormone 20-hydroxyecdysone (20e), acting via its nuclear receptor complex (ecr/usp), control gene expression at many stages throughout drosophila development. however, during the last larval instar of some lepidopteran insects, subtle changes in titers of ecdysteroids have been documented, including the so-called "commitment peak." this small elevation of 20e reprograms the larva for metamorphosis to the pupa. similar periods of ecdysteroid immunorea ...016273522
the drosophila microrna iab-4 causes a dominant homeotic transformation of halteres to wings.the drosophila bithorax complex encodes three well-characterized homeodomain proteins that direct segment identity, as well as several noncoding rnas of unknown function. here, we analyze the iab-4 locus, which produces the micrornas iab-4-5p and iab-4-3p. iab-4 is analogous to mir-196 in vertebrate hox clusters. previous studies demonstrate that mir-196 interacts with the hoxb8 3' untranslated region. evidence is presented that mir-iab-4-5p directly inhibits ubx activity in vivo. ectopic expres ...016357215
light on the moth-eye corneal nipple array of butterflies.the outer surface of the facet lenses in the compound eyes of moths consists of an array of excessive cuticular protuberances, termed corneal nipples. we have investigated the moth-eye corneal nipple array of the facet lenses of 19 diurnal butterfly species by scanning electron microscopy, transmission electron microscopy and atomic force microscope, as well as by optical modelling. the nipples appeared to be arranged in domains with almost crystalline, hexagonal packing. the nipple distances we ...016608684
condition-specific competition in container mosquitoes: the role of noncompeting life-history stages.condition-specific competition, wherein competitive superiority varies with the abiotic environment, can determine species' distributions in a spatially heterogeneous environment. we investigated this phenomenon with two competing container-dwelling mosquitoes. we tested the hypothesis that habitat drying alters the outcome of interspecific competition, predicting that the competitive impact of aedes albopictus on aedes aegypti would be severe in wetter environments, but greatly reduced in drier ...017450188
mutually exclusive splicing of the insect dscam pre-mrna directed by competing intronic rna secondary structures.drosophila dscam encodes 38,016 distinct axon guidance receptors through the mutually exclusive alternative splicing of 95 variable exons. importantly, known mechanisms that ensure the mutually exclusive splicing of pairs of exons cannot explain this phenomenon in dscam. i have identified two classes of conserved elements in the dscam exon 6 cluster, which contains 48 alternative exons--the docking site, located in the intron downstream of constitutive exon 5, and the selector sequences, which a ...016213213
females use self-referent cues to avoid mating with previous mates.females of many species mate repeatedly throughout their lives, often with many different males (polyandry). females can secure genetic benefits by maximizing their diversity of mating partners, and might be expected, therefore, to forego matings with previous partners in favour of novel males. indeed, a female preference for novel mating partners has been shown in several taxa, but the mechanism by which females distinguish between novel males and previous mates remains unknown. we show that fe ...016271971
a dynamic paracellular pathway serves diuresis in mosquito malpighian tubules.female mosquitoes gorge on vertebrate blood, a rich nutrient source for developing eggs, but gorging meals increase the risk of predation. mosquitoes are quick to reduce the flight payload with a potent diuresis. diuretic peptides of the insect kinin family induce a tenfold reduction in the paracellular resistance of malpighian tubules and increase the paracellular permeation of cl(-), the counterion of the transepithelial secretion of na(+) and k(+). as a result, the transepithelial secretion o ...022731730
identification, characterization and structure of a new delta class glutathione transferase isoenzyme.the insect gst (glutathione transferase) supergene family encodes a varied group of proteins belonging to at least six individual classes. interest in insect gsts has focused on their role in conferring insecticide resistance. previously from the mosquito malaria vector anopheles dirus, two genes encoding five delta class gsts have been characterized for structural as well as enzyme activities. we have obtained a new delta class gst gene and isoenzyme from a. dirus, which we name adgstd5-5. the ...015717864
influence of spatial heterogeneity on an emerging infectious disease: the case of dengue epidemics.the importance of spatial heterogeneity and spatial scales (at a village or neighbourhood scale) has been explored with individual-based models. our reasoning is based on the chilean easter island (ei) case, where a first dengue epidemic occurred in 2002 among the relatively small population localized in one village. even in this simple situation, the real epidemic is not consistent with homogeneous models. conversely, including contact heterogeneity on different scales (intra-households, inter- ...016024379
persistent emergence of dengue. 015898171
location of and landing on a source of human body odour by female culex quinquefasciatus in still and moving air.the orientation to and landing on a source of human odour by female culex quinquefasciatus say (diptera: culicidae) is observed in a wind tunnel without an airflow or with a laminar airflow of 0.2 m s(-1). odours from human feet are collected by 'wearing' clean glass beads inside a stocking and presenting beads in a petri dish in a wind tunnel. mosquitoes are activated by brief exposure to a 1 l min(-1) jet of 4% co2 positioned 10 cm from the release cage. in moving air at 0.2 m s(-1), a mean of ...026472918
high level of awareness but poor practices regarding dengue fever control: a cross-sectional study from north india.delhi, the capital of india, has suffered many outbreaks of dengue in recent past and despite the obvious magnitude of problem, very scarce evidence exists that documents the knowledge, awareness and practices of the people regarding dengue.022754880
a vitellogenin polyserine cleavage site: highly disordered conformation protected from proteolysis by phosphorylation.vitellogenin (vg) is an egg-yolk precursor protein in most oviparous species. in honeybee (apis mellifera), the protein (amvg) also affects social behavior and life-span plasticity. despite its manifold functions, the amvg molecule remains poorly understood. the subject of our structure-oriented amvg study is its polyserine tract - a little-investigated repetitive protein segment mostly found in insects. we previously reported that amvg is tissue specifically cleaved in the vicinity of this trac ...022573762
histone recognition and nuclear receptor co-activator functions of drosophila cara mitad, a homolog of the n-terminal portion of mammalian mll2 and mll3.mll2 and mll3 histone lysine methyltransferases are conserved components of compass-like co-activator complexes. in vertebrates, the paralogous mll2 and mll3 contain multiple domains required for epigenetic reading and writing of the histone code involved in hormone-stimulated gene programming, including receptor-binding motifs, set methyltransferase, hmg and phd domains. the genes encoding mll2 and mll3 arose from a common ancestor. phylogenetic analyses reveal that the ancestral gene underwent ...022569554
the combination of npk fertilizer and deltamethrin insecticide favors the proliferation of pyrethroid-resistant anopheles gambiae (diptera: culicidae).in this laboratory study, we investigated how the biological cycle of anopheles gambiae s.s. (vkpr strain) would be like when grew in an environment containing more or less plant matter (2.5 or 5 g/l) and fertilizer (8-12-8 or 17-23-17 mg/l). half of the environments studied were not exposed to insecticide (control) whereas the other half was submitted to deltamethrin treatment at the concentration of 0.015 mg/l. the bioassays showed that 2.5 g/l of plant matter in water are not sufficient to fe ...022550627
cadherin binding is not a limiting step for bacillus thuringiensis subsp. israelensis cry4ba toxicity to aedes aegypti larvae.bacillus thuringiensis subsp. israelensis produces three cry toxins (cry4aa, cry4ba and cry11aa) that are active against aedes aegypti larvae. the identification of the rate-limiting binding steps of cry toxins that are used for insect control in the field, such as those of b. thuringiensis subsp. israelensis, should provide targets for improving insecticides against important insect pests. previous studies showed that cry11aa binds to cadherin receptor fragment cr7-11 (cadherin repeats 7-11) wi ...022329749
analysis of lipolysis underlying lactation in the tsetse fly, glossina morsitans.female tsetse flies undergo viviparous reproduction, generating one larva each gonotrophic cycle. larval nourishment is provided by the mother in the form of milk secretions. the milk consists mostly of lipids during early larval development and shifts to a balanced combination of protein and lipids in the late larval instars. provisioning of adequate lipids to the accessory gland is an indispensable process for tsetse fecundity. this work investigates the roles of brummer lipase (bmm) and the a ...022509523
a review on the toxicity and non-target effects of macrocyclic lactones in terrestrial and aquatic environments.the avermectins, milbemycins and spinosyns are collectively referred to as macrocyclic lactones (mls) which comprise several classes of chemicals derived from cultures of soil micro-organisms. these compounds are extensively and increasingly used in veterinary medicine and agriculture. due to their potential effects on non-target organisms, large amounts of information on their impact in the environment has been compiled in recent years, mainly caused by legal requirements related to their marke ...022039795
dengue infections in travellers.dengue has been designated a major international public health problem by the world health organization (who). it is endemic in most tropical and sub-tropical countries, which are also popular tourist destinations. travellers are not only at significant risk of acquiring dengue but they also contribute to its spread to non-endemic regions. furthermore, they may serve as sentinels to alert the international community to epidemics in dengue-endemic regions. geosentinel, a global surveillance netwo ...022668447
dengue: an escalating public health problem in latin america.dengue infection is a significant and escalating public health problem in latin america. its re-emergence and subsequent rise in the region over the past 50 years has largely been caused by a combination of a lack of political will, the radical growth of urban populations, migration flow and insufficient financial resources. its increased incidence has been compounded by climate change, poor sanitation and extreme poverty, which lead to more breeding sites of the mosquito vector aedes aegypti. i ...022668444
the dengue situation in africa.dengue outbreaks and epidemics have been reported in all regions of africa, and it is believed that all four dengue virus serotypes are in circulation. available data suggest that dengue is endemic to 34 african countries and that aedes aegypti mosquitoes--the primary vector for dengue transmission--are known to be present in all but five countries. whether populations in africa are susceptible to dengue at the same rates as in asia and latin america is difficult to determine from the available ...022668445
evidence of polyandry for aedes aegypti in semifield enclosures.female aedes aegypti are assumed to be primarily monandrous (i.e., mate only once in their lifetime), but true estimates of mating frequency have not been determined outside the laboratory. to assess polyandry in ae. aegypti with first-generation progeny from wild mosquitoes, stable isotope semen-labeled males ((15)n or (13)c) were allowed to mate with unlabeled females in semifield enclosures (22.5 m(3)) in a dengue-endemic area in southern mexico. on average, 14% of females were positive for b ...022492148
proteome of aedes aegypti in response to infection and coinfection with microsporidian parasites.hosts are frequently infected with more than one parasite or pathogen at any one time, but little is known as to how they respond to multiple immune challenges compared to those involving single infections. we investigated the proteome of aedes aegypti larvae following infection with either edhazardia aedis or vavraia culicis, and coinfections involving both. they are both obligate intracellular parasites belonging to the phylum microsporidia and infect natural populations of ae. aegypti. the re ...022837817
knockdown resistance, rdl alleles, and the annual entomological inoculation rate of wild mosquito populations from lower moshi, northern tanzania.understanding vector behavioral response due to ecological factors is important in the control of disease vectors. this study was conducted to determine the knockdown resistance (kdr) alleles, dieldrin resistance alleles, and entomological inoculation rates (eirs) of malaria vectors in lower moshi irrigation schemes for the mitigation of disease transmission.022754247
dengue and us military operations from the spanish-american war through today.dengue is a major cause of illness among travelers and a threat to military troops operating in areas to which it is endemic. before and during world war ii, dengue frequently occurred in us military personnel in asia and the south pacific. from the 1960s into the 1990s, dengue often occurred in us troops in vietnam, the philippines, somalia, and haiti. we found attack rates as high as 80% and periods of convalescence up to 3-1/2 weeks beyond the acute illness. the increase in dengue throughout ...022469290
whole-genome sequence of wolbachia strain walbb, an endosymbiont of tiger mosquito vector aedes albopictus.although bacteria of the genus wolbachia induced significant extended phenotypes to infected hosts, most molecular mechanisms involved are still unknown. to gain insight into the bacterial genetic determinants, we sequenced the whole genome of wolbachia walbb strain, a commensal obligate intracellular of the tiger mosquito aedes albopictus.022408242
gene expression profiling in the thiamethoxam resistant and susceptible b-biotype sweetpotato whitefly, bemisia tabaci.thiamethoxam has been used as a major insecticide to control the b-biotype sweetpotato whitefly, bemisia tabaci (gennadius) (hemiptera: aleyrodidae). due to its excessive use, a high level of resistance to thiamethoxam has developed worldwide over the past several years. to better understand the molecular mechanisms underlying this resistance in b. tabaci, gene profiles between the thiamethoxam-resistant and thiamethoxam-susceptible strains were investigated using the suppression subtractive hyb ...022957505
complementary chimeric isoforms reveal dscam1 binding specificity in vivo.dscam1 potentially encodes 19,008 ectodomains of a cell recognition molecule of the immunoglobulin (ig) superfamily through alternative splicing. each ectodomain, comprising a unique combination of three variable (ig) domains, exhibits isoform-specific homophilic binding in vitro. although we have proposed that the ability of dscam1 isoforms to distinguish between one another is crucial for neural circuit assembly, via a process called self-avoidance, whether recognition specificity is essential ...022542180
community-based control of aedes aegypti by using mesocyclops in southern vietnam.we previously reported a new community-based mosquito control strategy that resulted in elimination of aedes aegypti (linn.) in 40 of 46 communes in northern and central vietnam, and with annual recurrent total costs (direct and indirect) of only $0.28-$0.89 international dollars per person. this control strategy was extended to four provinces in southern vietnam in long an and hau giang (2004-2007) and to long an, ben tre, and vinh long (2005-2010). in a total of 14 communes with 124,743 reside ...022556087
the economic burden of dengue. 022556068
return of epidemic dengue in the united states: implications for the public health practitioner.conditions that facilitate sustained dengue transmission exist in the united states, and outbreaks have occurred during the past decade in texas, hawaii, and florida. more outbreaks can also be expected in years to come. to combat dengue, medical and public health practitioners in areas with mosquito vectors that are competent to transmit the virus must be aware of the threat of reemergent dengue, and the need for early reporting and control to reduce the impact of dengue outbreaks. comprehensiv ...022547856
evolution of bmp signaling in drosophila oogenesis: a receptor-based mechanism.the bone morphogenetic protein (bmp) signaling pathway is a conserved regulator of cellular and developmental processes in animals. the mechanisms underlying bmp signaling activation differ among tissues and mostly reflect changes in the expression of pathway components. bmp signaling is one of the major pathways responsible for the patterning of the drosophila eggshell, a complex structure derived from a layer of follicle cells (fcs) surrounding the developing oocyte. activation of bmp signalin ...022768927
infertility resulting from transgenic i-ppoi male anopheles gambiae in large cage trials.anopheles gambiae is the primary vector of malaria in sub-saharan africa and is a potential target of genetic control programs. we determined the capacity of male a. gambiae created by germline transformation to introduce infertility into stable age-distribution populations. we also determined effects of the transgenes on life history.022595271
the effect of ivermectin in seven strains of aedes aegypti (diptera: culicidae) including a genetically diverse laboratory strain and three permethrin resistant strains.seven different strains of aedes aegypti (l.), including a genetically diverse laboratory strain, three laboratory-selected permethrin-resistant strains, a standard reference strain, and two recently colonized strains were fed on human blood containing various concentrations of ivermectin. ivermectin reduced adult survival, fecundity, and hatch rate of eggs laid by ivermectin-treated adults in all seven strains. the lc50 of ivermectin for adults and the concentration that prevented 50% of eggs f ...022493855
study on the correlation of premises condition index and the presence of larvae of aedes species mosquitoes in human dwellings of the cuddalore district of tamil nadu, india.it is concluded that this study helps in conducting rapid survey to identify the presence of aedes larvae with a minimum number of staff for both inspection and treatment of aedes larvae during the epidemic situation.024159479
mosquitocidal properties of natural product compounds isolated from chinese herbs and synthetic analogs of curcumin.because of resistance to current insecticides and to environmental, health, and regulatory concerns, naturally occurring compounds and their derivatives are of increasing interest for the development of new insecticidal compounds against vectors of disease-causing pathogens. fifty-eight compounds, either extracted and purified from plants native to china or synthetic analogs of curcumin, were evaluated for both their larvicidal activity against aedes aegypti (l.) and their ability to inhibit bin ...022493854
aedes albopictus mosquitoes, yucatan peninsula, mexico. 022377491
wedding fever: fever in the returning traveler. diagnosis: dengue fever. 023851538
distinct intracellular motifs of delta mediate its ubiquitylation and activation by mindbomb1 and neuralized.dsl proteins are transmembrane ligands of the notch receptor. they associate with a ring (really interesting new gene) family e3 ubiquitin ligase, either neuralized (neur) or mindbomb 1 (mib1), as a prerequisite to signaling. although neur and mib1 stimulate internalization of dsl ligands, it is not known how ubiquitylation contributes to signaling. we present a molecular dissection of the intracellular domain (icd) of drosophila melanogaster delta (dl), a prototype dsl protein. using a cell-bas ...022162135
aedes aegypti mosquitoes imported into the netherlands, 2010.during summer 2010, aedes aegypti mosquitoes were discovered in the netherlands. using genetic markers, we tracked the origin of these mosquitoes to a tire shipment from miami, florida, usa. surveillance of tire exports from the united states should be included as part of a comprehensive surveillance system.022172498
spatial stability of adult aedes aegypti populations.vector control programs could be more efficient by identifying the location of highly productive sites of aedes aegypti. this study explored if the number of female adults of ae. aegypti in bg-sentinel traps was clustered and if their spatial distribution changed in time in two neighborhoods in san juan, puerto rico. traps were uniformly distributed across each neighborhood (130 m from each other), and samples were taken every 3 weeks. global and local spatial autocorrelations were explored. spa ...022144449
the monarch butterfly genome yields insights into long-distance migration.we present the draft 273 mb genome of the migratory monarch butterfly (danaus plexippus) and a set of 16,866 protein-coding genes. orthology properties suggest that the lepidoptera are the fastest evolving insect order yet examined. compared to the silkmoth bombyx mori, the monarch genome shares prominent similarity in orthology content, microsynteny, and protein family sizes. the monarch genome reveals a vertebrate-like opsin whose existence in insects is widespread; a full repertoire of molecu ...022118469
public health as an international problem: 1944. 022676498
advances in developing a climate based dengue outbreak models in dhaka, bangladesh: challenges & opportunities. 022885257
characterization of lipophorin receptor (lpr) mediating the binding of high density lipophorin (hdlp) in the silkworm, bombyx mori.in an earlier report, we described the gene encoding a lipophorin receptor (lpr) of the silkworm, bombyx mori l. (lepidoptera: bombycidae), and recombinant expression of the protein. the present study was performed to characterize the corresponding native bmlpr and its binding characteristics. polyclonal anti-lpr antibody prepared against the cloned receptor fragment from the cytoplasmic domain specifically detected the receptor. through immunoblotting, ovary and brain membrane protein samples o ...022236107
cdna cloning and expression pattern of homolog of alpha subunit of platelet-activating factor acetylhydrolase ib from the chinese oak silkworm, antheraea pernyi.platelet-activating factor acetylhydrolase (paf-ah) is an enzyme that catalyzes the hydrolysis of platelet-activating factor (paf). a homolog of alpha subunit of paf-ah(ib) from antheraea pernyi (guérin-méneville) (lepidoptera: saturniidae) (appafahibĪ±) was isolated and characterized. the obtained cdna sequence was 1843 base pairs (bp) long with an open reading frame (ore) of 678 bp encoding 225 amino acids. the predicted amino acid sequence shared several conserved features of paf-ahs of other ...022224584
new approaches to the inhibition of replication of viral pathogens.this meeting was a special symposium sponsored by the american society for biochemistry and molecular biology. the conference was held in gangzhou, china on 24-26 july 2011 and shared a venue with the society of chinese bioscientists in america thirteenth international symposium. over 150 participants from the americas, europe, asia and australia attended the meeting. this article focuses on two areas of research in which there have been exciting developments that have application to the develop ...022029515
genetics and morphology of aedes aegypti (diptera: culicidae) in septic tanks in puerto rico.dengue viruses, primarily transmitted by the mosquito aedes aegypti (l.), affect an estimated 50-100 million people yearly. traditional approaches to control mosquito population numbers, such as the use of pesticides, have had only limited success. atypical mosquito behavior may be one reason why current vector control efforts have been less efficacious than expected. in puerto rico, for example, adult ae. aegypti have been observed emerging from septic tanks. interestingly, adults emerging from ...022238867
the basic reproduction number r0 and effectiveness of reactive interventions during dengue epidemics: the 2002 dengue outbreak in easter island, chile.we use a stochastic simulation model to explore the effect of reactive intervention strategies during the 2002 dengue outbreak in the small population of easter island, chile. we quantified the effect of interventions on the transmission dynamics and epidemic size as a function of the simulated control intensity levels and the timing of initiation of control interventions. because no dengue outbreaks had been reported prior to 2002 in easter island, the 2002 epidemic provided a unique opportunit ...024245625
evaluation of the traditional and revised world health organization classifications of dengue cases in brazil.dengue is a worldwide public health problem with approximately 50 million cases reported annually. the world health organization proposed a revised classification system in 2008 to more effectively identify the patients who are at increased risk of complications from dengue. few studies have validated this new classification system in clinical practice. we conducted a cross-sectional study of patients hospitalized for dengue in dourados, mato grosso do sul, brazil, to evaluate the capacity of th ...024212835
birth of three stowaway-like mite families via microhomology-mediated miniaturization of a tc1/mariner element in the yellow fever mosquito.eukaryotic genomes contain numerous dna transposons that move by a cut-and-paste mechanism. the majority of these elements are self-insufficient and dependent on their autonomous relatives to transpose. miniature inverted repeat transposable elements (mites) are often the most numerous nonautonomous dna elements in a higher eukaryotic genome. little is known about the origin of these mite families as few of them are accompanied by their direct ancestral elements in a genome. analyses of mites in ...024068652
bacteria mediate oviposition by the black soldier fly, hermetia illucens (l.), (diptera: stratiomyidae).there can be substantial negative consequences for insects colonizing a resource in the presence of competitors. we hypothesized that bacteria, associated with an oviposition resource and the insect eggs deposited on that resource, serve as a mechanism regulating subsequent insect attraction, colonization, and potentially succession of insect species. we isolated and identified bacterial species associated with insects associated with vertebrate carrion and used these bacteria to measure their i ...023995019
leishmania amazonensis exhibits phosphatidylserine-dependent procoagulant activity, a process that is counteracted by sandfly saliva.leishmania parasites expose phosphatidylserine (ps) on their surface, a process that has been associated with regulation of host's immune responses. in this study we demonstrate that ps exposure by metacyclic promastigotes of leishmania amazonensis favours blood coagulation. l. amazonensis accelerates in vitro coagulation of human plasma. in addition, l. amazonensis supports the assembly of the prothrombinase complex, thus promoting thrombin formation. this process was reversed by annexin v whic ...024037188
distribution, seasonal variation & dengue transmission prediction in sisaket, thailand.environmental factors including weather variables may play a significant role in the transmission of dengue. this study investigated the effect of seasonal variation on the abundance of aedes aegypti and ae. albopictus larvae and explored the impact of weather variability on dengue transmission in sisaket, thailand.024135179
rapid evolution of reduced receptivity to interspecific mating in the dengue vector aedes aegypti in response to satyrization by invasive aedes albopictus.in this paper we examine the effect of reproductive interference on the dynamics of two mosquito vectors of public health concern and add to the growing literature on the strength and speed with which interspecific reproductive interference may drive evolution. recent evidence supports a role for asymmetric reproductive interference, or satyrization, in competitive displacements of aedes aegypti by aedes albopictus. however, populations of a. aegypti sympatric with a. albopictus in nature evolve ...024563572
lessons from studying insect symbioses.as in mammals, insect health is strongly influenced by the composition and activities of resident microorganisms. however, the microbiota of insects is generally less diverse than that of mammals, allowing microbial function in insects to be coupled to individual, identified microbial species. this trait of insect symbioses facilitates our understanding of the mechanisms that promote insect-microbial coexistence and the processes by which the microbiota affect insect well-being. as a result, ins ...022018236
identification and characterization of heat shock 70 genes in aedes aegypti (diptera: culicidae).heat shock genes are highly evolutionarily conserved and are expressed to varying degrees in all organisms in response to stress. heat shock 70 (hsp70) genes have been well characterized in a number of organisms, most notably drosophila melanogaster, but not as yet for any of the major arthropod-borne viral mosquito vectors. to identify hsp70 genes in the yellow fever mosquito, aedes aegypti (diptera: culicidae), basic local alignment searches of the ae. aegypti genome were performed using d. me ...019496419
density-dependent intraspecific competition in the larval stage of aedes aegypti (diptera: culicidae): revisiting the current paradigm.density-dependent intraspecific competition has been considered an important determinant of the dynamics of larval stages of aedes aegypti. a model was published in 1984 providing a mathematical description of this density dependence, based on field data, that has since been widely used. this description, however, is based on the strong assumption that all mortality is density-dependent. we re-examine the data without this premise and find a reduced importance of density dependence, as well as a ...019496407
mucopolysaccharidosis type i in 21 czech and slovak patients: mutation analysis suggests a functional importance of c-terminus of the idua protein.mucopolysaccharidosis type i (mps i) is an autosomal recessive lysosomal storage disorder that is caused by a deficiency of the enzyme alpha-l-iduronidase (idua). of the 21 czech and slovak patients who have been diagnosed with mps i in the last 30 years, 16 have a severe clinical presentation (hurler syndrome), 2 less severe manifestations (scheie syndrome), and 3 an intermediate severity (hurler/scheie phenotype). mutation analysis was performed in 20 mps i patients and 39 mutant alleles were ...019396826
the ldl receptor.in this article, the history of the ldl receptor is recounted by its codiscoverers. their early work on the ldl receptor explained a genetic cause of heart attacks and led to new ways of thinking about cholesterol metabolism. the ldl receptor discovery also introduced three general concepts to cell biology: receptor-mediated endocytosis, receptor recycling, and feedback regulation of receptors. the latter concept provides the mechanism by which statins selectively lower plasma ldl, reducing hear ...019299327
mosquito wars. 019377708
editorial: 2008 year in review. 025567842
on-chip solid-phase extraction pre-concentration/focusing substrates coupled to atmospheric pressure matrix-assisted laser desorption/ionization ion trap mass spectrometry for high sensitivity biomolecule analysis.atmospheric pressure matrix-assisted laser desorption/ionization (ap-maldi) has proven a convenient and rapid method for ion production in the mass spectrometric (ms) analysis of biomolecules. ap-maldi and electrospray ionization (esi) sources are easily interchangeable in most mass spectrometers. however, ap-maldi suffers from less-than-optimal sensitivity due to ion losses during transport from the atmosphere into the vacuum of the mass spectrometer. here, we study the signal-to-noise ratio (s ...019140128
dengue transmission. 019270769
revisiting the cellular mechanisms of strong luminal alkalinization in the anterior midgut of larval mosquitoes.here we critically review two recent hypotheses about the mechanism of strong alkalinization by the anterior midgut of mosquito larvae and our tests of these hypotheses. we present experimental evidence against the major components of transport models proposed in these hypotheses. measurements of the transapical and transbasal proton electrochemical gradients provide an indication of driving forces faced by and generated by the transport mechanisms of the tissue. these measurements confirmed tha ...019151212
an extraovarian protein accumulated in mosquito oocytes is a carboxypeptidase activated in embryos.we report a phenomenon previously unknown for oviparous animals; in aedes aegypti mosquitoes a serine carboxypeptidase is synthesized extraovarially and then internalized by oocytes. the cdna encoding mosquito vitellogenic carboxypeptidase (vcp) was cloned and sequenced. the vcp cdna hybridizes to a 1.5-kilobase mrna present only in the fat body of vitellogenic females. the deduced amino acid sequence of vcp shares significant homology with members of the serine carboxypeptidase family. binding ...01961751
polyamine synthesis by the mermithid nematode romanomermis culicivorax.the polyamine and amino acid composition of the mermithid nematode, romanomermis culicivorax, and its host, aedes aegypti, was determined. putrescine, spermidine, spermine, cadaverine and two acetylated spermidine derivatives were present in parasitic juveniles, newly-emerged post-parasites, and eggs of r. culicivorax. whole insect homogenates of fourth-instar a. aegypti contained the same array of polyamines, except that the putrescine:spermidine ratio was the inverse of that in parasitic r. cu ...019287579
what can be learnt about selection from gene frequency distribution?polymorphism has been studied at the esterase 6 locus in the yellow fever mosquito aedes aegypti (l.) in laboratory stocks. at least 12 alleles are present, with up to four coexisting in a stock. the allele frequency distribution is quite sharply peaked at a mode of about 0.25. the experimental data are compared with the results of simulation based on two models, one in which the initial global distribution is taken to be the stationary distribution obtained from the neutral model assuming m = 4 ...03792826
transport of palmitic acid across the tegument of the entomophilic nematode romanomermis culicivorax.romanomermis culicivorax juveniles, dissected out of aedes aegypti larvae 7 days after infection, were incubated under controlled conditions in isotonic saline containing (1)c-u-palmitic acid to investigate the nature of the transport mechanism(s) used by the nematode for transcuticular uptake of palmitic acid. net uptake of the isotope by the nematode was of a logarithmic nature with respect to time. uptake of palmitic acid was accomplished by a combination of diffusion and a mediated process w ...019295867
effect of aedes aegypti (diptera:culicidae) age on sex ratios in romanomermis culicivorax (nematoda:mermithidae).first, second, third, early and late fourth-instar larvae, and pupae of aedes aegypti were infected with romanomerrais culicivorax and reared at 20, 25, and 30 c. an increase in the ratio of male to female nematodes was observed with increase in host age at the time of infection at each temperature. the number of pupal and late fourth-instar infections was low, but r. culicivorax continued to develop in adult a. aegypti. since male nematodes were recovered from both male and female hosts infecte ...019295853
glutathione biosynthesis in the aging adult yellow-fever mosquito [aedes aegypti (louisville)].our previous findings [hazelton & lang (1978) fed. proc. fed. am. soc. exp. biol. 37(6), 2378 (abstr.)] demonstrated a senescence-specific decrease in glutathione (gsh) concentration in the yellow-fever mosquito aedes aegypti (louisville)]. as a possible mechanism for this change, gsh biosynthesis was investigated in adult mosquitoes of different ages through the life-span. biosynthesis was measured as the incorporation rate of [14c]glycine or [14c]cystine into glutathione. essential information ...06860301
glutathione s-transferase activities in the yellow-fever mosquito [aedes aegypti (louisville)] during growth and aging.our previous findings [hazelton & lang (1978) fed. proc. fed. am. soc. exp. biol. 37(6), 2378 (abstr.)] demonstrated aging-specific changes in glutathione concentrations in the yellow-fever mosquito [aedes aegypti (louisville)]. a possible mechanism could be increased utilization via glutathione s-transferase. thus glutathione s-transferase activities were measured in mosquito samples from the entire life span, including growth, maturity and senescence. methods were validated for the quantitativ ...06860300
uptake of lipids by the entomophilic nematode romanomermis culicivorax.romanomermis culicivorax juveniles were dissected out of aedes aegypti larvae 7 days after infection and incubated under controlled conditions in isotonic saline containing a (1)c-labeled fatty acid (palmitic acid), monoacylglycerol (glycerol monoolein), or triacylglycerol (glycerol tripalmate) nutrient source. the mermithid absorbed each of these lipids from the incubation medium, the rate of uptake being greatest for glycerol monoolein. no lipase activity was detected in whole nematode homogen ...019295741
role of a modified ovitrap in the control of aedes aegypti in houston, texas, usa.a modified ovitrap from which larvae could not escape was employed for one year for the control of aedes aegypti at blossom heights, houston, texas. at the end of this period, the breteau index in the ovitrap area had declined by 36%, in contrast to a sharp increase of nearly 500% in the non-ovitrap area. the premises index in the ovitrap area remained unchanged, while the index in the non-ovitrap area increased by 440%. the problems associated with this control campaign and the use of these "au ...06980740
effects of host diet on romanomermis culicivorax, a mermithid parasite of mosquitoes.when larval mosquitoes (aedes aegypti) infected with the mermithid nematode romanomermis culicivorax were fed on a diet low in quantity or protein content or both, the number of postparasites which emerged from the hosts decreased and host mortality increased marginally. parasitic development was prolonged and became asynchronous in nutritionally deprived hosts. nematodes emerged from insects infected by more than one nematode before the remaining juveniles comprising such infections had complet ...019300764
the biosynthesis of deoxyribonucleic acid during the life-span of the mosquito.previous results from this laboratory [kao et al, (1976) biochem. j. 154, 471-480] demonstrated that a low-molecular-weight dna species, "sdna", present in high concentrations during rapid larval growth of the yellow-fever mosquito, aedes aegypti, may be an intermediate in dna replication. we have now determined the life-span profiles of synthetic rates and the steady-state contents of sdna and total dna by radiometric and biochemical procedures and by using mosquitoes grown and maintained under ...0938460
a deoxyribonucleic acid-replication intermediate in the growing mosquito.in previous experiments on growth and aging in the yellow-fever mosquito, aedes aegypti, a low mol. wt. (500000) dna species was found in the supernatant fraction after ultracentrifugation of homogenates of rapidly-growing larvae. this dna species, "sdna", constituted 30-40% of total dna in 2-4-day-old larvae, but was less than 5% in older larvae, pupae and adults. we have now isolated and characterized sdna and initiated experiments to determine its metabolic role. isolated sdna has the same ph ...0938459
the ovary as a source of alpha-ecdysone in an adult mosquito.the ovaries of the mosquito aedes aegypti cultured in vitro secrete material that behaves like ecdysone in a radioimmunoassay. the material was identified as alpha-ecdysone by high-resolution liquid and gas-liquid chromatography. secretion reached a maximum 16 hr after a blood meal as shown by bioassay and direct determination. ovariectomy reduced the concentration of ecdysone in the adult after a blood meal. qualitative analysis of whole-body extracts indicated beta-ecdysone to be the principal ...01059110
diminution and enlargement of the mosquito rhabdom in light and darkness.the rhabdoms of the larval ocelli of the mosquito aedes aegypti undergo morphological light and dark adaptation over periods of hours. the rhabdom enlarges during dark adaptation and grows smaller during light adaptation. diminution is exponential, enlargement linear, and rates of change are proportional to log light intensity. rhabdoms maintained at a constant intensity level off at a constant volume proportional to log intensity. we argue that changes in rhabdom volume after changes in light i ...01176940
ecdysone-mediated stimulation of dopa decarboxylase activity and its relationship to ovarian development in aedes aegypti.very little dopa decarboxylase activity is detectable in adult female mosquitoes aedes aegypti which have not been allowed to engorge blood. however, when such females are injected with the molting hormone beta-ecdysone a marked stimulation of this enzyme's activity is observable. no stimulation is observed in males similarly injected, nor in females injected with cholesterol or a juvenile hormone mimic. in addition, ecdysone injection initiates ovarian development in these anautogenous non-bloo ...04827909
the control of aedes aegypti during the yellow fever epidemic in luanda, angola, in 1971.vector control was carried out in three cycles with ulv technical malathion sprayed from aircraft at the application rate of 500 ml/ha. successive reductions of 84%, 93.6%, and 96% in the pretreatment density of a. aegypti were attained, a range of 77-98% being observed over a 24-day period.04543554
spectral sensitivity of larval mosquito ocelli.the spectral sensitivity of lateral ocelli in both wild-type and white-eyed larvae of the yellow fever mosquito aedes aegypti l. (reared in darkness) was measured by means of the electroretinogram. the spectral sensitivity is maximal at about 520 nm, with a small secondary peak near 370 nm. when allowance is made for some screening and filtering by the eye tissues, the spectral sensitivity is in reasonable agreement with the absorption spectrum of ocellar rhodopsin (lambda(max) = 515 nm).05029552
rhodopsin of the larval mosquito.larvae of the mosquito aedes aegypti have a cluster of four ocelli on each side of the head. the visual pigment of each ocellus of mosquitoes reared in darkness was characterized by microspectrophotometry, and found to be the same. larval mosquito rhodopsin (lambda(max) = 515 nm) upon short irradiation bleaches to a stable photoequilibrium with metarhodopsin (lambda(max) = 480 nm). on long irradiation of glutaraldehyde-fixed tissues or in the presence of potassium borohydride, bleaching goes fur ...05029551
permeability of the ovarian follicle of aedes aegypti mosquitoes.the passage of tracers of various molecular weights into resting and vitellogenic ovarian follicles of aedes aegypti mosquitoes was studied ultrastructurally. the outermost layer of the follicular sheath (the basement lamina) is a coarse mechanical filter. it is freely permeable to particles with molecular weights ranging from 12,000 to 500,000 (i.e. cytochrome c, peroxidase, hemoglobin, catalase, ferritin, immunoglobulin (igg)-peroxidase, iron dextran and thorotrast) that have dimensions less t ...04104968
ultra-low-volume ground aerosols of technical malathion for the control of aedes aegypti l.the efficacy of malathion aerosols applied from the ground was evaluated for the control of ae. aegypti. several techniques for applying the aerosols to an inhabited locality were investigated, and it was found that excellent control of adult mosquitos could be obtained with a dosage of 438 ml/ha. two treatments carried out 3 days apart enabled the adult mosquito population to be reduced by 99%, and it took about 2 weeks to regain its pretreatment level. schedules of treatment and strategies to ...05317014
[aedes aegypti and potential vectors of yellow fever in the democratic republic of somalia and in the french territory of afars and issas]. 05316916
[sensitivity of and resistance to insecticides of aedes aegypti in west africa and methods of control of the vector]. 05316917
population control potential of heterozygous translocations as determined by computer simulations.a possible method for genetic control of insect vector species involves the use of translocation heterozygotes. the potential of single and double heterozygotes already available in aedes aegypti has been investigated with computer simulations of release strategies. such simulations indicate a possible role for translocation heterozygotes of these types in an insect population characterized by a 5-fold population growth per generation, or less.05317450
survival and development of a tropical mosquito, aedes aegypti, in southern england. 05316751
evaluation of ultra-low-volume insecticide dispensing systems for use in single-engined aircraft and their effectiveness against aedes aegypti populations in south-east asia.an evaluation study of ultra-low-volume (ulv) spraying of insecticide from aircraft was carried out in thailand, to determine if this technique could be used for the emergency control of aedes aegypti, the major vector of haemorrhagic fever. a small, single-engined aircraft, a cessna-180, was used in the trials and 2 types of spraying equipment were tested; both were found to be equally effective. the aircraft was fitted with 6 spraying nozzles and flew at an altitude of 150 feet (46 m) at a spe ...05309517
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