larval occurrence, oviposition behavior and biting activity of potential mosquito vectors of dengue on samui island, thailand.a 1995 outbreak of dengue haemorrhagic fever (dhf) occurred on samui island in thailand with an incidence of almost 500 cases/100,000 population. to find and develop effective strategies to control this disease through cost-effective vector control programs, entomological studies were carried out on the island between 1996 and 1998. there were two species of dhf vectors, aedes aegypti and ae. albopictus prevailing on the island, and the population of ae. aegypti remained relatively constant thro ...200111813654
[incidence of aedes (s) aegypti and other culicidae in the municipality of playa, la habana city].an analysis was made on the incidence of culicidae present in playa municipality, havana city, during the intensive stage of the anti-aegypti campaign from june to july, 1997, according to its requirements. culex quinquefasciatus was the predominant species with a total of 269 focuses. it was collected in all the people's councils and in every type of repository, excepting clay repositories. the second most abundant species was the aedes aegypti with 199 focuses, followed by aedes mediovittatus ...200011826519
[the community and the control of aedes aegypti: perception and behavior regarding temephos larvicide].given the persistence of aedes aegypti foci in the santiago de cuba municipality in 1998, a survey was made among the dwellers of the houses to find out their acceptance and behaviour in relation with temephos, to precise over the reasons why the product was not kept in water containers and to know the aspects associated with the existence of foci and their control. it was found that there were filled water tanks in houses where there was daily water supply so that dirt can deposit and water be ...200111826537
a cluster of four d7-related genes is expressed in the salivary glands of the african malaria vector anopheles gambiae.four genes expressed in the anopheles gambiae adult female salivary glands and similar in sequence to the aedes aegypti d7 gene were identified. the genes, called d7-related (d7r), are included in a single cluster encompassing approximately six kilobases on chromosome arm 3r. the deduced proteins contain secretory signals and they are probably injected by the mosquito into the host with the saliva during blood feeding. the region of similarity to d7 encompasses the carboxy-terminal part of the a ...200211841502
toxicity and synergism in transgenic escherichia coli expressing four genes from bacillus thuringiensis subsp. israelensis.the genes cyt1aa and p20, encoding, respectively, cytolytic and accessory proteins of bacillus thuringiensis subsp. israelensis, were introduced into previously constructed clones expressing cry4aa and cry11aa in escherichia coli (ben-dov et al., 1995). fifteen clones with all possible combinations of the four genes were obtained and found to express the genes included. two new combinations, pve4-adrc and pve4-arc, expressing cyt1aa, p20 and cry4aa, with or without cry11aa, respectively, were mo ...200111846773
screening of some romanian plants for their activity against medically important insects.the effects of the action of extracts from 82 plant species included in 39 families of indigenous flora against the larvae and adults of house fly (musca domestica), the mosquitoes (aedes aegypti and anopheles atroparvus) and the german cockroach (blattella germanica) are presented. some of the extracts were prepared from air-dried and ground plant material which was exhaustively extracted with successive solvents of different polarity: ethyl ether, ethyl alcohol and water. other extracts were p ...200011850879
naturally exposed populations differ in their t1 and t2 responses to the circumsporozoite protein of plasmodium falciparum.t-cell responses directed against the circumsporozoite protein (cs) of plasmodium falciparum can mediate protection against malaria. we determined the frequency of t cells reactive to different regions of the cs in the blood of donors naturally exposed to p. falciparum by examining t1 (gamma interferon [ifn-gamma] elispot assay), t2 (interleukin 4 [il-4] elispot assay), and proliferative t-cell responses. the proliferative responses were weak, which confirmed previous observations. the responses ...200211854234
monoclonal antibody against the plasmodium falciparum chitinase, pfcht1, recognizes a malaria transmission-blocking epitope in plasmodium gallinaceum ookinetes unrelated to the chitinase initiate invasion of the mosquito midgut, plasmodium ookinetes secrete chitinases that are necessary to cross the chitin-containing peritrophic matrix en route to invading the epithelial cell surface. to investigate chitinases as potential immunological targets of blocking malaria parasite transmission to mosquitoes, a monoclonal antibody (mab) was identified that neutralized the enzymatic activity of the sole chitinase of plasmodium falciparum, pfcht1, identified to date. this mab, designate ...200211854247
yellow fever: an update.yellow fever, the original viral haemorrhagic fever, was one of the most feared lethal diseases before the development of an effective vaccine. today the disease still affects as many as 200,000 persons annually in tropical regions of africa and south america, and poses a significant hazard to unvaccinated travellers to these areas. yellow fever is transmitted in a cycle involving monkeys and mosquitoes, but human beings can also serve as the viraemic host for mosquito infection. recent increase ...200111871403
characterization of cyt2bc toxin from bacillus thuringiensis subsp. medellin.we cloned and sequenced a new cytolysin gene from bacillus thuringiensis subsp. medellin. three is240-like insertion sequence elements and the previously cloned cyt1ab and p21 genes were found in the vicinity of the cytolysin gene. the cytolysin gene encodes a protein 29.7 kda in size that is 91.5% identical to cyt2ba from bacillus thuringiensis subsp. israelensis and has been designated cyt2bc. inclusions containing cyt2bc were purified from the crystal-negative strain spl407 of b. thuringiensi ...200211872472
transfer rna-dependent amino acid biosynthesis: an essential route to asparagine formation.biochemical experiments and genomic sequence analysis showed that deinococcus radiodurans and thermus thermophilus do not possess asparagine synthetase (encoded by asna or asnb), the enzyme forming asparagine from aspartate. instead these organisms derive asparagine from asparaginyl-trna, which is made from aspartate in the trna-dependent transamidation pathway [becker, h. d. & kern, d. (1998) proc. natl. acad. sci. usa 95, 12832-12837; and curnow, a. w., tumbula, d. l., pelaschier, j. t., min, ...200211880622
dengue virus infections.dengue is the most important arthropod-borne viral disease of public health significance. its geographic distribution includes more than 100 countries worldwide, where more than 2.5 billion people are at risk for dengue infections. most people will have asymptomatic infections, but the disease manifestations range from an influenza-like disease known as dengue fever to a severe, sometimes fatal disease characterized by hemorrhage and shock, known as dengue hemorrhagic fever/dengue shock syndrome ...200211880737
aedes aegypti transducing densovirus pathogenesis and expression in aedes aegypti and anopheles gambiae larvae.aedes aegypti densovirus (aednv) is a small dna virus that has been developed into an expression and transducing vector for mosquitoes [afanasiev et al. (1994) exp parasitol 79: 322-339; afanasiev et al. (1999) virology 257: 62-72; carlson et al. (2000) insect transgenesis: methods and applications (handler, a.m. & james, a.a., eds), pp. 139-159. crc press, boca raton]. virions carrying a recombinant genome expressing the gfp gene were used to characterize the pathogenesis of the virus in 255 in ...200111881803
cloning and molecular characterization of two mosquito iron regulatory proteins.iron regulatory proteins (irps) control the synthesis of various proteins at the translational level by binding to iron responsive elements (ires) in the mrnas. iron, infection, and stress can alter irp/ire binding activity. insect messenger rnas for ferritin and succinate dehydrogenase subunit b have ires that are active translational control sites. we have cloned and sequenced cdnas encoding proteins from the irp1 family for the mosquitoes, aedes aegypti and anopheles gambiae. both deduced ami ...200211891134
dengue: an update.this review is an update of dengue and dengue haemorrhagic fever (dhf) based on international and cuban experience. we describe the virus characteristics and risk factors for dengue and dhf, and compare incidence and the case fatality rates in endemic regions (southeast asia, western pacific, and the americas). the clinical picture and the pathogenesis of the severe disease are explained. we also discuss the viral, individual, and environmental factors that determine severe disease. much more re ...200211892494
nk t cells are a source of early interleukin-4 following infection with third-stage larvae of the filarial nematode brugia pahangi.infection of c57bl/6 mice with the third-stage larvae of brugia pahangi results in a rapid expansion of nk1.1(+) t cells in the spleen and draining lymph nodes. nk t cells produced interleukin-4 in the spleen within 24 h of infection, and these cells were cd4(-).200211895990
observations on the breeding habitat of aedes species in the steel township, rourkela.prompted by report of large number of dengue fever cases in township of rourkela steel plant, entomological surveys were carried out to know the distribution and extent of aedes breeding in and around the dengue fever affected areas. out of 2062 water containers searched, 819 were positive for aedes larvae. the house index (hi), container index (ci) and breteau index (bi) were 53.4, 39.7 and 118.5 respectively. 27.9% of the houses had single breeding habitats. the breateau index of single storey ...200111898460
larvicidal activity of isobutylamides identified in piper nigrum fruits against three mosquito species.the insecticidal activity of materials derived from the fruits of piper nigrum against third instar larvae of culex pipiens pallens, aedes aegypti, and a. togoi was examined and compared with that of commercially available piperine, a known insecticidal compound from piper species. the biologically active constituents of p. nigrum fruits were characterized as the isobutylamide alkaloids pellitorine, guineensine, pipercide, and retrofractamide a by spectroscopic analysis. retrofractamide a was is ...200211902925
microsatellite markers for population genetic studies in aedes aegypti (diptera: culicidae) from côte d'ivoire: evidence for a microgeographic genetic differentiation of mosquitoes from bouaké.in west africa, aedes aegypti (diptera: culicidae) (linnaeus, c., 1762. zweyter theil, enhalt beschreibungen veschiedener wichtiger naturalien. in: hasselquist, f. (ed.), reise nach palastina in den jahren von 1749 bis 1752, rostock, germany, pp. 267-606) represents the principal vector of yellow fever. this study reports the use of microsatellite markers to characterise various a. aegypti populations from côte d'ivoire according to a north-south transect, and to perform a temporal genetic surve ...200211904102
specific detection of chikungunya virus using a rt-pcr/nested pcr combination.chikungunya (chik) virus is enzootic in many countries in asia and throughout tropical africa. in asia the virus is transmitted from primates to humans almost exclusively by aedes aegypti, while various aedine mosquito species are responsible for human infections in africa. the clinical picture is characterized by a sudden onset of fever, rash and severe pain in the joints which may persist in a small proportion of cases. although not listed as a haemorrhagic fever virus, illness caused by chik ...200211911593
epidemiological significanceof subterranean aedes aegypti (diptera: culicidae) breeding sites to dengue virus infection in charters towers, 1993.the objective of this study wasto determine the epidemiological significance of subterranean mosquito breeding sites to the 1993 outbreak of dengue fever (type 2) in the northern queensland town of charters towers, australia. in recent studies on subterranean mosquito breeding, containers such as wells and service manholes have been shown to be important breeding sites to australia's only dengue vector, aedes aegypti (l.). this study demonstrates a direct epidemiological association between subt ...200211931248
dengue in cuba: mobilisation against aedes aegypti. 200211937420
dengue virus infection rate in field populations of female aedes aegypti and aedes albopictus in singapore.we developed a single-step reverse transcription-polymerase chain reaction (rt-pcr) followed by a semi-nested pcr using an upstream consensus primer and four type-specific primers within the non-structural protein gene (ns3) of dengue viruses to type dengue viruses in field populations of female aedes mosquitoes. this yielded diagnostic fragments of 169, 362, 265 and 426 base pairs for dengue virus types 1, 2, 3 and 4, respectively. from 1997 to 2000, 54 (6.9%) of 781 aedes aegypti and 67 (2.9%) ...200211952948
isolation of cdna clones encoding putative odourant binding proteins from the antennae of the malaria-transmitting mosquito, anopheles way of controlling disease transmission by blood-feeding mosquitoes is to reduce the frequency of insect-host interaction, thus reducing the probability of parasite transmission and re-infection. a better understanding of the olfactory processes responsible for allowing mosquitoes to identify human hosts is required in order to develop methods that will interfere with host seeking. we have therefore initiated a molecular approach to isolate and characterize the genes and their products that ...200211966877
germ line transformation of the yellow fever mosquito, aedes aegypti, mediated by transpositional insertion of a piggybac vector.mosquito-vectored diseases such as yellow fever and dengue fever continue to have a substantial impact on human populations world-wide. novel strategies for control of these mosquito vectored diseases can arise through the development of reliable systems for genetic manipulation of the insect vector. a piggybac vector marked with the drosophila melanogaster cinnabar (cn) gene was used to transform the white-eyed khw strain of aedes aegypti. microinjection of preblastoderm embryos resulted in fou ...200211966878
the d7 family of salivary proteins in blood sucking diptera.the d7 subfamily of salivary proteins is widespread in blood sucking diptera and belongs to the superfamily of pheromone/odourant binding proteins. although d7 proteins are among the most abundant salivary proteins in adult female mosquitoes and sand flies, their role in blood feeding remains elusive. in the present work we report the sequence of seventeen novel d7 proteins, and propose an evolutionary scenario for the appearance of the several forms of this protein, based on a total of twenty-o ...200211966880
potential application of nonstructural protein ns1 serotype-specific immunoglobulin g enzyme-linked immunosorbent assay in the seroepidemiologic study of dengue virus infection: correlation of results with those of the plaque reduction neutralization ns1 serotype-specific indirect enzyme-linked immunosorbent assay (elisa) was developed to differentiate primary and secondary dengue virus infections and serotypes of primary dengue virus infection. for this report, we carried out retrospective seroepidemiologic studies on serum samples collected from residents of liuchiu hsiang, pingtung county, an isolated island in southern taiwan during 1997-1998. the results demonstrated that good correlation existed between dengue virus ns1 serotype-spe ...200211980973
hospital-based diagnosis of hemorrhagic fever, encephalitis, and hepatitis in cambodian children.surveillance was conducted for three clinical syndromes (hemorrhagic fever, encephalitis, and hepatitis) in cambodian children admitted to the national pediatric hospital in phnom penh from july 1996 through september 1998. acute- and convalescent-phase sera, and cerebrospinal fluid, when applicable, underwent diagnostic evaluation for infections with dengue virus (denv), japanese encephalitis virus (jev), and hepatitis a, b, c, and e viruses. of 621 children admitted with hemorrhagic fever, 499 ...200211996683
do plasmodium ookinetes invade a specific cell type in the mosquito midgut?recent debate in plasmodium ookinete invasion has been centered on whether the parasite chooses a specific cell type to cross the midgut epithelium in the mosquito. a few publications have described the mosquito midgut being composed of complex surface-structures, histochemically and biochemically diverse cell types, and have proposed that plasmodium gallinaceum ookinetes prefers a specific cell type (ross cell) in aedes aegypti for crossing the midgut epithelium. two recent publications reporte ...200211998702
an inexpensive intervention for the control of larval aedes aegypti assessed by an improved method of surveillance and analysis.a sampling method coupled with statistical calibration factors was developed to accurately assess the numbers of larvae and pupae of aedes aegypti in large water-storage containers of variable capacities and water levels. aedes aegypti productivity in different types of breeding sites found in an urban study area in central colombia was assessed and compared. in this study, water-storage tanks and drums were found to comprise 79% of the containers positive for larval ae. aegypti, which contribut ...200211998929
indoor thermal fogging against vector mosquitoes with two bacillus thuringiensis israelensis formulations, vectobac abg 6511 water-dispersible granules and vectobac 12as liquid.bioefficacy of thermal fogging application of 2 bacillus thuringiensis israelensis formulations, vectobac abg 6511 water-dispersible granules (3,000 international toxic unit [itu]/mg) and vectobac 12as liquid (1,200 itu/mg), was assessed for larvicidal activities against aedes aegypti, aedes albopictus, anopheles dirus, and culex quinquefasciatus. portable agrofog af35 sprayers were used to apply the 2 formulations indoors in residential premises on penang island, malaysia. vectobac abg 6511 sho ...200211998931
an isolate of bacillus circulans toxic to mosquito larvae.a new strain of bacillus circulans isolated from a larva of culex quinquefasciatus showed larvicidal activity on 3 mosquitoes of medical importance. compared to bacillus sphaericus strain 2362, this b. circulans isolate proved less toxic to cx. quinquefasciatus and anopheles gambiae but was 107 times more toxic to aedes aegypti. moreover, in comparison to other studies, b. circulans was at least as pathogenic as b. thuringiensis var. israelensis in ae. aegypti. the tests have showed that the tox ...200211998934
ecdysteroids and oocyte development in the black fly simulium vittatum.oocyte development was studied in the autogenous black fly, simulium vittatum (diptera, nematocera), a vector of onchocerca volvulus, the causative agent of onchocerciasis.200212015816
vector infection determinants of venezuelan equine encephalitis virus reside within the e2 envelope glycoprotein.epizootic subtype iab and ic venezuelan equine encephalitis viruses (veev) readily infect the epizootic mosquito vector aedes taeniorhynchus. the inability of enzootic subtype ie viruses to infect this mosquito species provides a model system for the identification of natural viral determinants of vector infectivity. to map mosquito infection determinants, reciprocal chimeric viruses generated from epizootic subtype iab and enzootic ie veev were tested for mosquito infectivity. chimeras containi ...200212021373
detection of west nile virus antigen in mosquitoes and avian tissues by a monoclonal antibody-based capture enzyme antigen capture immunoassay to detect west nile (wn) virus antigen in infected mosquitoes and avian tissues has been developed. with this assay purified wn virus was detected at a concentration of 32 pg/0.1 ml, and antigen in infected suckling mouse brain and laboratory-infected mosquito pools could be detected when the wn virus titer was 10(2.1) to 10(3.7) pfu/0.1 ml. in a blindly coded set of field-collected mosquito pools (n = 100), this assay detected wn virus antigen in 12 of 18 (66.7%) ...200212037058
polygamy: the possibly significant behavior of aedes aegypti and aedes albopictus in relation to the efficient transmission of dengue virus.the polygamous behavior of male aedes aegypti (l.) and ae. albopictus (skuse) was investigated by co-habiting a newly-emerged male and females in a 30 cm3 cage (1 male: 20 females) for up to 5 consecutive days. as determined by insemination rates, the results indicated that one ae. aegypti and ae. albopictus male could successfully mate with 1.10 (0-4), 4.10 (1-8), 5.40 (4-8), 5.10 (2-8), 5.15 (3-9) and 0.20 (0-3), 1.70 (0-3), 2.35 (1-4), 2.30 (0-4), 2.35 (1-4) ae. aegypti and ae. albopictus fem ...200112041548
[epidemiology of dengue infection in ribeirão preto, sp, brazil].to assess dengue transmission in a correctional facility for juvenile delinquents in ribeirão preto, state of são paulo, brazil.200212045796
[presence of aedes aegypti in bromeliaceae and plant breeding places in brazil].the frequency of bromeliaceae and other plant breeding places where aedes aegypti can be found is reported during two consecutive operational cycles (focal treatment) in the city of rio de janeiro. these cycles took place from november 12 2000 to march 9 2001 and from march 12 2001 to june 15 2001. this study concentrates on the epidemiological implications resulting from the growing use of these plants as decorative living objects.200212045807
education in primary school as a strategy to control dengue.the proliferation of aedes aegypti, a species of mosquito that is the vector of the dengue pathogen, is being augmented by the population's lack of care in allowing the formation of larval habitats. one form of controlling dengue is the distribution of information on the mosquito to improve awareness and to provide the means necessary for the elimination of its reproductive habitats. to evaluate a teaching method concerning the vector and dengue, students from the 5th and 6th years of primary ed ...200212045814
oral susceptibility to yellow fever virus of aedes aegypti from brazil.the oral susceptibility to yellow fever virus was evaluated in 23 aedes aegypti samples from brazil. six ae. aegypti samples from africa, america and asia were also tested for comparison. mosquito samples from asia showed the highest infection rates. infection rates for the brazilian ae. aegypti reached 48.6%, but were under 13% in 60% of sample tested. we concluded that although the low infection rates estimated for some brazilian mosquito samples may not favor the establishment of urban cycle ...200212048581
[critical aspects of dengue control in brazil].dengue is now the main reemerging disease in the world. in the absence of an efficacious preventive vaccine and effective etiologic treatment and chemoprophylaxis, the only vulnerable link for reducing dengue transmission is the mosquito aedes aegypti, its principal vector. there are many difficulties in combating this mosquito in large and medium-sized cities. the complexity of contemporary urban life generates factors that facilitate the mosquito's proliferation and constraints on the reductio ...200212048612
in vitro cultivation of infective larvae of dirofilaria immitis.infective larvae (l3) of dirofilaria immitis were cultivated in various synthetic media. l3 obtained from aedes aegypti mosquitoes by mass dissection were inoculated into the media, viz: rpmi 1640 medium with 10 per cent human ab serum (medium-a); tc-199 medium with organic acids, sugars of grace's insect medium and 10 per cent foetal calf serum (fcs) (medium-b); and grace's insect medium with 10 per cent fcs (medium-c). maximum survival of 26 days was found in medium 'a'. approximately 80 per c ...198412055792
a theoretical approach to predicting the success of genetic manipulation of malaria mosquitoes in malaria control.mosquitoes that have been genetically modified to better encapsulate the malaria parasite plasmodium falciparum are being considered as a possible tool in the control of malaria. hopes for this have been raised with the identification of genes involved in the encapsulation response and with advances in the tools required to transform mosquitoes. however, we have only very little understanding of the conditions that would allow such genes to spread in natural populations.200212057019
interaction of 65- and 62-kd proteins from the apical membranes of the aedes aegypti larvae midgut epithelium with cry4b and cry11a endotoxins of bacillus thuringiensis.a protein with the molecular weight of 65 kd is the only component of aedes aegypti larvae bbm capable to specifically bind mosquitocidal toxins cry4b and cry11a of bacillus thuringiensis. this protein lacks the leucine aminopeptidase activity which is characteristic for the toxin-binding proteins from the membranes of caterpillars. cry-toxins inactive against a. aegypti larvae either fail to bind to the 65-kd protein and to a putative product of its proteolysis with the molecular weight of 62 k ...200212059773
mating alters the cuticular hydrocarbons of female anopheles gambiae sensu stricto and aedes aegypti (diptera: culicidae).the cuticular hydrocarbons of female anopheles gambiae giles sensu stricto and aedes aegypti (l.) mosquitoes were analyzed before and after they mated. in an. gambiae, the proportions of the two cuticular hydrocarbon components, n-heneicosane and n-tricosane, were significantly reduced as the female aged and after it mated. there were no changes in the hydrocarbon composition of males after they mated. hydrocarbon extracts from mated and unmated an. gambiae females as well as those from males ca ...200212061454
temporal genetic variation in aedes aegypti populations in ho chi minh city (vietnam).aedes aegypti, the main vector of dengue viruses in asia, displays variation in population density over time. the larval habitats of this species being unevenly distributed and transient (depending on cycles of drought and flood), the forces generating temporal variation in gene frequencies in populations are studied. we sampled seven mosquito populations from ho chi minh city (vietnam) and its suburbs on five occasions between april 1999 and august 2000. we investigated genetic variation by stu ...200212080364
isolation of chikungunya virus from aedes aegypti mosquitoes collected in the town of yawat, pune district, maharashtra state, india.chikungunya (chik) virus is prevalent throughout southeast asia and africa. it has caused numerous large outbreaks in india. no active or passive surveillance has been carried out since the last epidemic occurring in 1971. during a recent outbreak of dengue (den)-like illness in eastern india, aedes aegypti mosquitoes collected from the affected area were positive for chik virus. evidence of dual infection with chik and den typel virus was also obtained. a widely circulating low-virulent chik vi ...200112083330
preadult stage parasites and multiple timed exposure to infective larvae are involved in development of limb edema in brugia malayi-infected indian leaf monkeys (presbytis entellus).the pathogenesis of filarial limb edema is not known. the role of parasitological variables and parasite-mediated phenomena in the development of limb edema was investigated in the presbytis entellus-brugia malayi model. infection was initiated with subcutaneous inoculation of infective third-stage larvae (l(3)), and the animals were reexposed to different doses of l(3) at the prepatent, patent, and diminishing microfilaremia (0 to 5% of peak microfilaremia count) stages of infection. a large l( ...200212093695
first outbreak of dengue hemorrhagic fever, bangladesh.during the first countrywide outbreak of dengue hemorrhagic fever in bangladesh, we conducted surveillance for dengue at a hospital in dhaka. of 176 patients, primarily adults, found positive for dengue, 60.2% had dengue fever, 39.2% dengue hemorrhagic fever, and 0.6% dengue shock syndrome. the dengue virus 3 serotype was detected in eight patients.200212095447
new enamine derivatives of lapachol and biological activity.a convenient synthesis of the new enamine derivatives 2-(4-morpholinyl)-3-(3-methyl-2-butenyl)-1,4-naphthalenedione, 2-(1-piperidinyl)-3-(3-methyl-2-butenyl)-1,4-naphtalenedione and 2-(1-pyrrolidinyl)-3-(3-methyl-2-butenyl)-1,4-naphthalenedione was carried out from natural 2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphthalenedione (lapachol) and morpholine, piperidine and pyrrolidine. the structures of the products were established mainly by nmr analysis, including 2d experiments. biological activiti ...200212098751
insulin receptor expression during development and a reproductive cycle in the ovary of the mosquito aedes aegypti.a key tyrosine kinase receptor regulates steroidogenesis during egg maturation in the mosquito aedes aegypti. this study examined expression patterns and phosphorylation states of the mosquito insulin receptor (mir) in ovaries during the previtellogenic stage and a reproductive cycle. little or no mir protein was present until 24 h after adult eclosion, when the mature mir appeared as a approximately 400-kda tetrameric protein composed of two 116-kda alpha-subunits and two 95-kda beta-subunits. ...200212107434
isolation, characterization, and functional expression of kynurenine aminotransferase cdna from the yellow fever mosquito, aedes aegypti(1).this study describes the molecular and biochemical characterization of kynurenine aminotransferase (kat) from aedes aegypti mosquitoes. through screening an a. aegypti larval cdna library, a 1695-bp full-length cdna clone with a 1434-bp open reading frame (orf) was isolated. its deduced amino acid sequence consists of 477 amino acid residues with a predicted molecular mass of 53,490 and the amino acid sequence shares 47 and 42% identity with kats from homo sapiens and rattus norvegicus, respecti ...200212110301
the use of commercial saponin from quillaja saponaria bark as a natural larvicidal agent against aedes aegypti and culex pipiens.the larvicidal activity of commercial bark saponin extract (sigma) from quillaja saponaria was studied on 3rd-4th instar larvae of aedes aegypti and culex pipiens (vectors for dengue fever and western nile virus, respectively). the larvae were exposed to serial concentrations (1000, 800, 500, 300, 100, 10, 1, 0.1 and 0.01 mg/l) of the extract for 1, 3, 5, 7 and 11 days. the results indicate that commercial bark saponin is toxic, causing 100% larval mortality in a. aegypti and c. pipiens after 1 ...200212127245
gender-related family head schooling and aedes aegypti larval breeding risk in southern investigate if family head genre-associated education is related to the risk of domiciliary aedes aegypti larval breeding in a dengue-endemic village of southern mexico.200212132321
dengue virus selectively induces human mast cell chemokine production.severe dengue virus infections usually occur in individuals who have preexisting anti-dengue virus antibodies. mast cells are known to play an important role in host defense against several pathogens, but their role in viral infection has not yet been elucidated. the effects of dengue virus infection on the production of chemokines by human mast cells were examined. elevated levels of secreted rantes, mip-1alpha, and mip-1beta, but not il-8 or ena-78, were observed following infection of ku812 o ...200212134044
control of aedes vectors of dengue in three provinces of vietnam by use of mesocyclops (copepoda) and community-based methods validated by entomologic, clinical, and serological surveillance.we describe remarkable success in controlling dengue vectors, aedes aegypti (l.) and aedes albopictus (skuse), in 6 communes with 11,675 households and 49,647 people in the northern provinces of haiphong, hung yen, and nam dinh in vietnam. the communes were selected for high-frequency use of large outdoor concrete tanks and wells. these were found to be the source of 49.6-98.4% of ae. aegypti larvae, which were amenable to treatment with local mesocyclops, mainly m. woutersi van der velde, m. as ...200212135266
breeding structure of aedes aegypti populations in mexico varies by region.a population genetic analysis of aedes aegypti was conducted among 38 collections from throughout coastal regions of mexico. multiple collections were made within 5 cities to examine local patterns of gene flow. single-strand conformation polymorphism analysis was used to screen for variation in a 387-bp region of the nicotinamide adenine dinucleotide dehydrogenase subunit 4 mitochondrial gene (nd4) and 25 haplotypes were detected. northeastern mexico collections were genetically differentiated ...200212135296
comparison of penaeid shrimp and insect parvoviruses suggests that viral transfers may occur between two distantly related arthropod groups.the dna and putative amino acid sequences of representative insect and shrimp parvoviruses (subfamily densovirinae) were analyzed using computer programs. shrimp viruses included hepatopancreatic parvovirus (hpv) of penaeus monodon (hpvmon) and p. chinensis (hpvchin), spawner-isolated mortality virus from p. monodon (smvmon) and infectious hypodermal and hematopoietic necrosis virus (ihhnv) from p. vannamei. insect viruses included aedes aegypti densovirus (aaednv), aedes albopictus densovirus ( ...200212135792
[repellent activity against aedes aegypti (l.) of formulas based on natural vegetable extracts or synthetic active agents].a comparison of 5 commercial mosquito repellents was made on adult male and female volunteers in laboratory trials. the products tested in forms of cream or lotion included 4 natural oil formulations (containing citronella, clover, eucalyptus, geranium, lavender, peppermint, sandalwood, thyme, etc.) and 1 synthetic chemical repellent containing 10% kbr 3023). natural oil products showed essentially poor or no repellency against ae, aegypti: the protection times were less than or equal to 1 hour. ...200212162118
[aedes albopictus (s) in the region of são josé do rio preto, sp, brazil: a study of its infestation in an area where aedes aegypti was already established and a discussion of its role as a possible vector of dengue and yellow fever].the objectives of this survey were to study the evolution of aedes albopictus infestation in são josé do rio preto region, sp, an area already occupied by aedes aegypti and also to discuss its role in transmitting diseases. analyzing data from urban mosquito larval density surveys of the region's municipalities, year and site of the occurrence, composition and location of larval samples, breeding containers and breteau indices were studied. by may 2001, the vector was found in 96 of 100 municipa ...200212170331
comparative toxicity of selected larvicidal formulations against anopheles stephensi liston and aedes aegypti linn.toxicity of selected larvicidal formulations of bacillus sphaericus, bacillus thuringiensis h-14 israelensis (bti) and insect growth regulators was determined against anopheles stephensi and aedes aegypti, the two major urban mosquito vectors of malaria and dengue fever in india respectively. the study revealed that the formulations of bacillus thuringiensis h-14 and igr compounds were highly toxic against both the mosquito species but bacillus sphaericus formulation was less toxic against aedes ...200112170930
the characterization of ion regulation in amazonian mosquito larvae: evidence of phenotypic plasticity, population-based disparity, and novel mechanisms of ion uptake.this study is the first step in characterizing ion uptake mechanisms of mosquito larvae from the amazon region of brazil. hemolymph nacl levels and rates of unidirectional na(+) and cl(-) uptake were measured in larvae of aedes aegypti and culex quinquefasciatus in a series of environmental manipulations that are known to challenge ion regulation in other aquatic animals. despite being reared for numerous generations in dilute media (20 micromol l(-1) nacl), both species were able to maintain hi ...200212177826
complete mitochondrial dna sequence and amino acid analysis of the cytochrome c oxidase subunit i (coi) from aedes aegypti.the complete sequence of the yellow fever mosquito, aedes aegypti, mitochondrial cytochrome c oxidase subunit 1 gene has been identified. the nucleotide sequence codes for a 512 amino acid peptide. the aecoi sequence is a + t rich (68.6%) and the codon usage is highly biased toward a preference for a- or t-ending triplets. the a. aegypti coi peptide shows high homology, up to 93% identity, with several other insect sequences and a phylogenetic analysis indicates that the a. aegypti sequence is c ...200212180346
reverse genetics in the mosquito anopheles gambiae: targeted disruption of the defensin gene.anopheles gambiae, the major vector of human malaria parasite, is an important insect model to study vector-parasite interactions. here, we developed a simple in vivo double-stranded rna (dsrna) knockout approach to determine the function of the mosquito antimicrobial peptide gene defensin. we injected dsrna into adults and observed efficient and reproducible silencing of defensin. analysis of the knockdown phenotype revealed that this peptide is required for the mosquito antimicrobial defense a ...200212189180
hepatozoon species (apicomplexa: hepatozoidae) of the corn snake, elaphe guttata (serpentes: colubridae) and the pigmy rattlesnake, sistrurus miliarius barbouri (serpentes: viperidae) in south florida.hepatozoon guttata n. sp. is described from the corn snake (elaphe guttata guttata) from south florida. gamonts average 14.6 x 4.6 (13-17 x 3.5-6) and are not recurved, with nucleus situated in the second quarter of the gamont. erythrocyte cytoplasm rarely appears partially dehemoglobinized. the infected cells are usually distorted and are longer than the uninfected erythrocytes but do not differ in width; nuclei are smaller in length and width than those of uninfected cells. sporogony in aedes ...200212197130
the status of haemogregarina mansoni sambon and seligmann from zamenis flagelliformis laurenti.haemogregarina mansoni sambon and seligmann 1907, a parasite of the coachwhip snake (masticophis flagellum) is redescribed on the basis of sporogonic stages obtained in the experimental vector aedes aegypti and designated as hepatozoon mansoni from hosts collected in north florida. gamonts average 14.7 x 4.7 (13-16 x 4-6) and are not recurved, with nuclei situated in the second quarter of the gamont. erythrocyte cytoplasm is often thin, appearing partially dehemoglobinized, or contracted into a ...200212197131
effect of anticoagulants on the susceptibility of aedes aegypti mosquitoes to dengue virus infection. 200212197636
comparative safety and immunogenicity of two yellow fever 17d vaccines (arilvax and yf-vax) in a phase iii multicenter, double-blind clinical trial.yellow fever (yf) is a significant health problem in south america and africa. travelers to these areas require immunization. the united states, infested with aedes aegypti mosquitoes, is at risk of introduction of this disease. there is only a single u.s. manufacturer of yf 17d vaccine, and supplies may be insufficient in an emergency. a randomized, double-blind outpatient study was conducted in 1,440 healthy individuals, half of whom received the u.s. vaccine (yf-vax) and half the vaccine manu ...200212201587
large genetic distances among aedes aegypti populations along the south pacific coast of mexico.a population genetic analysis was conducted among 20 aedes aegypti collections from 19 cities along the south pacific coast in the mexican states of guerrero, oaxaca, and chiapas and in coatepeque, guatemala. genetic variation was scored at 131 random amplified polymorphic dna loci. the amount of genetic differentiation among collections was approximately 3 times as great as detected among collections in an earlier study in northeastern mexico. regression analysis of linear or road distances on ...200212201597
genetic differentiation of the dengue vector, aedes aegypti (ho chi minh city, vietnam) using microsatellite markers.dengue haemorrhagic fever emerged in the 1950s and has become a major public health concern in most asian countries. in vietnam, little is known about the intraspecific variation of the vector and its consequences on vectorial capacity. here we report the use of microsatellite markers to differentiate aedes aegypti populations in ho chi minh city, a typical, overcrowded asian city. six microsatellite loci, with 5-14 alleles per locus, were scored in 20 mosquito samples collected in 1998 in ho ch ...200212207714
reduced efficacy of the immune melanization response in mosquitoes infected by malaria parasites.although the mosquito vectors of malaria have an effective immune system capable of encapsulating many foreign particles, they rarely encapsulate malaria parasites in natural populations. a possible reason for this apparent paradox is that infection by malaria reduces the capability of the mosquito to mount an effective immune response. to investigate this possibility, we blood-fed aedes aegypti mosquitoes on an uninfected chicken or on one infected with plasmodium gallinaceum, and compared the ...200212211612
dynamics of dengue virus circulation: a silent epidemic in a complex urban area.serotypes of dengue den-1 and den-2 have been reported in much of brazil over the last 15 years, and den-3 serotype was only recently detected. this prospective study was conducted in salvador, a large city in north-east brazil, where two epidemics were previously recorded (den-1 and den-2). we obtained the seroprevalence and 1-year incidence of dengue infections in the population of 30 sampling areas of salvador and analysed the relationship between intensity of viral circulation, standard of l ...200212225506
engineering mosquito resistance to malaria parasites: the avian malaria model.genetic approaches to controlling the transmission of mosquito-borne diseases are being developed to augment the available chemical control practices and environmental manipulation methods. much progress has been made in laboratory-based research that seeks to develop antipathogen or antivector effector genes and methods for genetically manipulating host vector strains. research is summarized here in the development of a malaria-resistant phenotype using as a model system the avian parasite, pla ...200212225922
developing arbovirus resistance in mosquitoes.diseases caused by arthropod-borne viruses are increasingly significant public health problems, and novel methods are needed to control pathogen transmission. the hypothesis underlying the research described here is that genetic manipulation of aedes aegypti mosquitoes can profoundly and permanently reduce their competence to transmit dengue viruses to human hosts. recent key findings now allow us to test the genetic control hypothesis. we have identified viral genome-derived rna segments that c ...200212225924
infectious diseases in mexico. a survey from obtained at a central laboratory for emerging, re-emerging, and other infectious diseases in mexico from 1995-2000 are presented. an outstanding increase of den-3 circulation was identified. aedes aegypti, the dengue vector, is widely distributed. leptospirosis has become the most important differential diagnosis for dengue. identification of rabies virus variants allowed cataloging of new transmitters of rabies. rotavirus showed a clear seasonal distribution, while different proportions of ...200212234523
flavivirus susceptibility in aedes aegypti.aedes aegypti is the primary vector of yellow fever (yf) and dengue fever (df) flaviviruses worldwide. in this review we focus on past and present research on genetic components and environmental factors in aedes aegypti that appear to control flavivirus transmission. we review genetic relationships among ae. aegypti populations throughout the world and discuss how variation in vector competence is correlated with overall genetic differences among populations. we describe current research into h ...200212234528
development of monoclonal antibody based antigen capture elisa to detect chikungunya virus antigen in mosquitoes.chikungunya (chik) virus has caused numerous large outbreaks in india. no active or passive surveillance has been carried out since the last epidemic which occurred in 1971. for active surveillance, it is necessary to have a test, which can detect the virus from a large number of field-collected mosquitoes.200212239836
genetic differentiation of aedes aegypti mainland and island populations from southern thailand.isozymes of 5 wild-caught collections of aedes aegypti were compared by using starch gel electrophoresis. all collections were collected from surat-thanee province, southern thailand, an area considered to be a hyperendemic zone for dengue virus. one collection was from donsak harbor, whereas the other 4 collections were from 4 districts of samui island. the percent polymorphic loci (24.2-33%) in the 4 island collections was lower than in the mainland collection (36.4%). this study revealed a la ...200212322938
chemical analysis of human skin emanations: comparison of volatiles from humans that differ in attraction of aedes aegypti (diptera: culicidae).host odors are believed to play a major role in the location of blood meals by female mosquitoes. previous work has shown that female aedes aegypti (l.) are attracted to a residuum of skin emanations deposited on glass. the attraction of mosquitoes to handled or rubbed glass varies from person to person and from day to day. this variation indicates that mosquito behavior varies over time and that a relative difference exists in the ability of people over time to attract mosquitoes. volatiles des ...200212322940
larvicidal activity of leguminous seeds and grains against aedes aegypti and culex pipiens pallens.larvicidal activity of methanol extracts of 26 leguminous seeds and 20 grains against early 4th-stage larvae of aedes aegypti and culex pipiens pallens was examined. at 200 ppm of the extracts from cassia obtusifolia, cassia tora, and vicia tetrasperma, more than 90% mortality was obtained in larvae of ae. aegypti and cx. pipiens pallens. extract of c. tora gave 86.7 and 100% mortality in the larvae of ae. aegypti and cx. pipiens pallens at 40 ppm but 59.2 and 78.3% mortality against larvae of a ...200212322944
cloning and characterization of an insecticidal crystal protein gene from bacillus thuringiensis subspecies kenyae.a sporulating culture of bacillus thuringiensis subsp. kenyae strain hd549 is toxic to larvae of lepidopteran insect species such as spodoptera litura, helicoverpa armigera and phthorimaea operculella, and a dipteran insect, culex fatigans. a 1.9-kb dna fragment, pcr-amplified from hd549 using cryii-gene-specific primers, was cloned and expressed in e. coli. the recombinant protein produced 92% mortality in first-instar larvae of spodoptera litura and 86% inhibition of adult emergence in phthori ...200212357073
genetic structure of aedes aegypti populations in chiang mai (thailand) and relation with dengue transmission.we analysed the population genetic structure and differentiation regarding vector competence for a dengue virus of 15 aedes aegypti samples collected from chiang mai in northern thailand. based on polymorphism of 10 isoenzyme loci, genetic differentiation was confirmed among samples collected in different subdistricts (high fst values and p < 0.05). based on infection rate for a dengue 2 virus, susceptibilities were similar in mosquitoes collected in san nuea subdistrict and in choeng doi subdis ...200212358622
a putative receptor for dengue virus in mosquito tissues: localization of a 45-kda glycoprotein.dengue virus (denv) infects target cells by attaching to various cell receptors, many of which are still unknown. in c6/36 cells (aedes albopictus cell line), denv-4 bound to two glycoproteins of 40 and 45 kda, located on the cell surface. preincubation of cells with polyclonal antibody against the 45-kda protein specifically blocked denv-4 infection of c6/36 cells. the antibody and purified denv-4 detected the 45-kda molecule in total extracts from eggs, larvae, and pupae as well as from the mi ...200212363068
variation in vector competence for dengue 2 virus among 24 collections of aedes aegypti from mexico and the united states.aedes aegypti from 24 collections in mexico and the united states were challenged orally with dengue 2 virus jam1409 (den-2 jam1409). the vector competence (vc) of the populations ranged from 24% to 83%. mosquito populations from the yucatan exhibited greater vc than those from other areas of mexico. the presence or absence of a midgut infection barrier (mib) and a midgut escape barrier (meb) was determined for mosquitoes in each population. the percentage of mosquitoes exhibiting an mib ranged ...200212363070
a coup-tf/svp homolog is highly expressed during vitellogenesis in the mosquito aedes the mosquito aedes aegypti, vitellogenesis is activated via an ecdysteroid hormonal cascade initiated by a blood meal. the functional ecdysone receptor is a heterodimer composed of the ecdysone receptor (ecr) and ultraspiracle, the homolog of the retinoid x receptor. the precise tuning of this hormonal response requires participation of both positive and negative transcriptional regulators. in drosophila, svp, a homolog of chicken ovalbumin upstream promoter transcription factor (coup-tf), in ...200212370123
conservation of long-range synteny and microsynteny between the genomes of two distantly related nematodes.comparisons between the genomes of the closely related nematodes caenorhabditis elegans and caenorhabditis briggsae reveal high rates of rearrangement, with a bias towards within-chromosome events. to assess whether this pattern is true of nematodes in general, we have used genome sequence to compare two nematode species that last shared a common ancestor approximately 300 million years ago: the model c. elegans and the filarial parasite brugia malayi.200212372145
infection outcome and cytokine gene expression in brugia pahangi- infected gerbils (meriones unguiculatus) sensitized with brucella abortus.filarial infections have been associated with the development of a strongly polarized th2 host immune response and a severe impairment of mitogen-driven proliferation and type 1 cytokine production in mice and humans. the role of this polarization in the development of the broad spectra of clinical manifestations of lymphatic filariasis is still unknown. recently, data gathered from humans as well as from immunocompromised mouse models suggest that filariasis elicits a complex host immune respon ...200212379668
nitric oxide limits the expansion of antigen-specific t cells in mice infected with the microfilariae of brugia pahangi.infection of balb/c mice with the microfilariae (mf) of the filarial nematode brugia pahangi results in an antigen-specific proliferative defect that is induced by high levels of no. using carboxyfluorescein diacetate succinimydl ester and cell surface labeling, it was possible to identify a population of antigen-specific t cells from mf-infected balb/c mice that expressed particularly high levels of cd4 (cd4(hi)). these cells proliferated in culture only when inducible no synthase was inhibited ...200212379675
genome fragment of wolbachia endosymbiont transferred to x chromosome of host insect.the adzuki bean beetle, callosobruchus chinensis, is triple-infected with distinct lineages of wolbachia endosymbiont, wbrucon, wbruori, and wbruaus, which were identified by their wsp (wolbachia surface protein) gene sequences. whereas wbrucon and wbruori caused cytoplasmic incompatibility of the host insect, wbruaus did not. although wbrucon and wbruori were easily eliminated by antibiotic treatments, wbruaus persisted over five treated generations and could not be eliminated. the inheritance ...200212386340
suitability of containers from different sources as breeding sites of aedes aegypti (l.) in a cemetery of buenos aires city, argentina.cemeteries are ideal urban areas to study the importance of different types of containers as breeding sites of aedes aegypti (l.). in the present study, the suitability of plastic, glass, ceramic and metal containers was evaluated in four patches within a cemetery of buenos aires city, argentina. between october 1998 and may 2000, we found 215 breeding sites of ae. aegypti out of 13,022 water-filled containers examined. in two patches containing microenvironments sheltered from the sun, the use ...200212386697
dengue virus type 3 isolation from aedes aegypti in the municipality of nova iguaçu, state of rio de a prospective field study conducted from july 2000 to june 2001, adult aedes aegypti and ae. albopictus mosquitoes were caught from the municipality of nova iguaçu, state of rio de janeiro, brazil. virus isolation in ae. albopictus clone c6/36 cell line and a semi-nested reverse transcription-polymerase chain reaction detected only dengue virus type 3 in three pools of ae. aegypti, despite the co-circulation of den-1, den-2 and den-3 serotypes in that area. no viruses were detected in ae. alb ...200212386700
laboratory evaluation of mesocyclops annulatus (wierzejski, 1892) (copepoda: cyclopidea) as a predator of container-breeding mosquitoes in laboratory bioassays we tested the predatory capacity of the copepod mesocyclops annulatus on aedes aegypti and culex pipiens larvae. a single adult female of m. annulatus caused 51.6% and 52.3% mortality of 50 first instar larvae of ae. aegypti and cx. pipiens respectively, in a 72 h test period. when alternative food was added to the containers, mortality rates declined to 16% and 10.3% for ae. aegypti and cx. pipiens respectively. when 50 first instar larvae of each of the two mosquito spe ...200212386705
persistence of dengue-3 virus through transovarial transmission passage in successive generations of aedes aegypti mosquitoes.progeny of aedes aegypti mosquitoes infected intrathoracically with dengue-3 virus was reared to subsequent generations. in each generation, blood-fed females were confined individually and the eggs obtained from the transovarially infected females were pooled. the seventh generation obtained from the infected parental mosquitoes showed that virus could persist in mosquitoes in successive generations through transovarial passage. the rate of vertical transmission initially increased in the few g ...200212389940
roof gutters: a key container for aedes aegypti and ochlerotatus notoscriptus (diptera: culicidae) in australia.the contribution of roof gutters to aedes aegypti (l.) and ochlerotatus notoscriptus (skuse) pupal populations was quantified for the first time in cairns, australia. concurrent yard and roof surveys yielded an estimated 6,934 mosquito pupae, comprising four species. roof gutters were an uncommon but productive source of ae. aegypti in both wet season (n = 11) and dry season (n = 2) surveys, producing 52.6% and 39.5% of the respective populations. first story gutters accounted for 92.3% of the p ...200212408662
dengue and its vectors in thailand: introduction to the study and seasonal distribution of aedes larvae.a study was conducted from 1989 to 1994 that included surveillance for dengue and its mosquito vectors in 3 villages and 2 schools in chachoengsao province, 100 km east of bangkok, thailand. the study is introduced, and results of larval surveys for aedes mosquitoes (predominantly aedes aegypti (l.)), with 94, 86, and 90% of positive containers infested by this species in the hot, wet, and cool seasons, respectively), are described. these surveys were conducted in 1990-1991 during each of the 3 ...200212408663
growth characteristics of chimerivax-den2 vaccine virus in aedes aegypti and aedes albopictus mosquitoes.the chimeric yellow fever (yf) 17d-dengue type 2 (chimerivax-den2) vaccine virus developed by acambis, inc. (cambridge, ma) contains the prm and e genes of wild-type (wt) dengue 2 (den-2) (strain puo-218) virus in the yf vaccine virus (strain 17d) backbone. the potential of chimerivax-den2 virus to infect and be transmitted by aedes aegypti, the principal den and yf virus mosquito vector, and aedes albopictus, a species that occurs in areas of active transmission of yf and den viruses, was evalu ...200212408664
differential partitioning of maternal fatty acid and phospholipid in neonate mosquito animals, lipids are a source of energy, cell membrane components, signaling pathway modulators and emulsifying agents. in egg-laying animals, maternal yolk lipids, imported into the egg before laying, are metabolized or distributed in the developing embryo to serve these functions. studies with birds, reptiles and insects have described lipid metabolism in adults and in eggs, but no studies have addressed how lipids are distributed in developing organs in the embryo. here we show that materna ...200212409488
frequency, diversity, and productivity study on the aedes aegypti most preferred containers in the city of manaus, amazonas, brazil.the most preferred containers by aedes aegypti were studied april and july (rainy and dry periods) in two manaus neighbourhoods. in all, 2,700 premises and 13,912 containers were examined, most (87%) recorded outdoors. out of the 13,100 inspected premises, only 1.6% showed to be positive for aedes aegypti, summing up to 7,916 collected samples. most frequently found containers outdoors in either neighbourhood regardless of rain or dry period were bottles flasks and storage, and indoors, fixed, f ...200212436162
rna silencing of dengue virus type 2 replication in transformed c6/36 mosquito cells transcribing an inverted-repeat rna derived from the virus genome.double-stranded rna (dsrna) initiates cellular posttranscriptional responses that are collectively called rna silencing in a number of different organisms, including plants, nematodes, and fruit flies. in plants, rna silencing has been associated with protection from virus infection. in this study, we demonstrate that dsrna-mediated interference also can act as a viral defense mechanism in mosquito cells. c6/36 (aedes albopictus) cells were stably transformed with a plasmid designed to transcrib ...200212438618
the salivary purine nucleosidase of the mosquito, aedes aegypti.a cdna clone originating from adult female aedes aegypti mosquitoes was found with substantial similarity to nucleosidases of the ec enzyme class. although this type of enzyme is unusual in animals, abundant enzyme activity was found in salivary homogenates of this mosquito, but not in salivary homogenates of the mosquitoes anopheles gambiae and culex quinquefasciatus, or the sand fly lutzomyia longipalpis. aedes salivary homogenate hydrolyses inosine and guanosine to hypoxanthine and xa ...200312459196
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