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uptake and development of wuchereria bancrofti in aedes aegypti and haitian culex quinquefasciatus that were fed on a monkey with low-density microfilaremia.colonized mosquitoes of culex quinquefasciatus (haitian strain) and aedes aegypti (liverpool strain) were blood fed on a patas monkey (erythrocebus patas) that had been experimentally infected with the haitian strain of wuchereria bancrofti and harbored a consistently low microfilaremia (1-3 mf per 20 mm3). both species ingested more than twice the expected number of microfilariae (mf), i.e. 1.9 and 0.77 mf per mosquito, respectively. however, at 10-16 hours post ingestion only 4.2% of the mf ha ...19883057592
effect of nosema algerae vavra and undeen spores infection on longevity and fecundity of larval instars of aedes aegypti l. and culex fatigans weid. 19863108151
mechanical transmission of bacillus anthracis by stable flies (stomoxys calcitrans) and mosquitoes (aedes aegypti and aedes taeniorhynchus).we evaluated the potential of stable flies, stomoxys calcitrans, and two species of mosquitoes, aedes aegypti and aedes taeniorhynchus, to transmit bacillus anthracis vollum 1b mechanically. after probing on hartley guinea pigs with a bacteremia of ca. 10(8.6) cfu of b. anthracis per ml of blood, individual or pools of two to four stable flies or mosquitoes were allowed to continue feeding on either uninfected guinea pigs or a/j mice. all three insect species transmitted lethal anthrax infection ...19873112013
complement effects of the infectivity of plasmodium gallinaceum to aedes aegypti mosquitoes. ii. changes in sensitivity to complement-like factors during zygote development.during transformation into ookinetes, the zygotes of plasmodium gallinaceum are initially resistant to lysis by heat-labile and edta-sensitive factors in the serum of their natural host, the chicken. between 6 and 8 hr postgametogenesis, zygotes cultured in vitro lose their resistance to these factors. loss of resistance to these factors in vitro is reflected by loss of infectivity of the zygotes to aedes aegypti mosquitoes in the presence of native chicken serum. these factors are probably comp ...19873116195
exsheathment of microfilariae of brugia pahangi in the susceptible and refractory strains of aedes aegypti.exsheathment of microfilariae of brugia pahangi was studied in susceptible (liverpool) and refractory (bora-bora) strains of aedes aegypti. it was found that the microfilariae tend to carry their sheaths into the haemocoel of both strains of ae. aegypti within two hours after the engorgement of mosquitoes from a rat parasitized by filariae. the percentage of sheathed microfilariae in the haemocoel then progressively decreased to 0% at eight hours and to 1% at 24 hours post-ingestion in the bora- ...19883178339
toxicity of bacillus sphaericus crystal toxin to adult mosquitoes.adult culex quinquefasciatus mosquitoes were killed by alkaline-solubilized bacillus sphaericus toxin when it was introduced by enema into the midgut of the insect but not when it was administered orally. adult aedes aegypti mosquitoes were not affected by the toxin.19883190228
host range and selected factors influencing the mosquito larvicidal activity of the pg-14 isolate of bacillus thuringiensis var. morrisoni.laboratory bioassay of the pg-14 isolate of bacillus thuringiensis var. morrisoni (serotype 8a:8b) against early fourth instar larvae of 8 species of mosquitoes revealed a range of susceptibilities similar to the susceptibilities of these species to bacillus thuringiensis var. israelensis (serotype 14). the most susceptible species were: culex quinquefasciatus, cx. salinarius, anopheles albimanus and aedes aegypti. the least susceptible species tested was an. quadrimaculatus. separate bioassays ...19883193097
effects of larval nutrition on the host-seeking behavior of adult aedes aegypti mosquitoes.adult female aedes aegypti that were reared on a suboptimal diet as larvae were less likely to engage in host-seeking behavior than were adults derived from larvae reared on an optimal diet. a postemergence carbohydrate diet of either 1 or 10% sucrose solution did not affect this response. when the progeny of field-collected aedes vexans were reared in the laboratory, the adults were significantly larger than their parents. this indicated that the larvae of the field population were not as adequ ...19883193101
method for determining settling rates of bacillus thuringiensis serotype h-14 formulations.a water-column apparatus is described in which settling rates of bacillus thuringiensis serotype h-14 [b.t. (h-14)] formulations can be indirectly quantified using mortality of mosquito larvae at restricted depths as an index of b.t. (h-14) activity. to illustrate the type of data provided by this method, commercial b.t. (h-14) products (bactimos, teknar, vectobac) and experimental formulations were compared at the manufacturers' recommended rates for mosquito control. all evaluations utilized l ...19883193109
evaluating ultra-low volume ground applications of malathion against aedes aegypti using landing counts in puerto rico, 1980-84.landing counts made in a residential area in san juan, puerto rico during the 5-year period, 1980-84 indicated that malathion ulv applied by leco fog generators was not effective against aedes aegypti. of 25 applications only 6 resulted in a decrease on the first day after treatment and only one remained much less than the pretreatment count on the second and third days after treatment. daily, the number of mosquitoes landing for a 5-minute period at each of 2 stations was recorded. an ideal yea ...19883193113
feeding behavior of aedes aegypti larvae and toxicity of dispersed and of naturally encapsulated bacillus thuringiensis var. israelensis. 19883198932
efficacy of two formulations of bacillus thuringiensis var. israelensis (h-14) against aedes vexans and safety to non-target macroinvertebrates.an experimental sandoz formulation of bacillus thuringiensis var. israelensis (san 402 sc 98) was several times more effective than abbott abg 6188 against larvae of aedes aegypti and ae. vexans in the laboratory. field applications of san 402 sc 98 at 0.25 liter/ha and abg 6188 at 1.00 liter/ha resulted in more than 97% control of ae. vexans larvae after 48 hours, with residual activity of 24 hours or less. the amphipod, hyallela azteca, and 4 species of water beetles were apparently unaffected ...19883199115
[susceptibility of aedes aegypti l. mosquitoes infected with an entomopathogenic virus to malarial plasmodia]. 19883231163
[arbovirus infections on the island of nosy-be; serologic and entomologic findings].since 1977, the pasteur institute of madagascar has been studying, during six surveys, the arboviruses of nosy-be area, in the north-west of madagascar. 47.2 p. 100 out of 271 human sera and 11.3 p. 100 out of 150 animal sera (mostly from lemurs), tested for antibodies to 16 arboviruses by the haemagglutination inhibition test, are positive. the results show an important prevalence of flaviviruses. west-nile and dengue 1 viruses were probably circulating some years before the surveys. antibodies ...19883242421
[toxic effects of bacillus thuringiensis var. kurstaki to the immature stage of aedes aegypti]. 19883244164
comparative toxicity of bacillus thuringiensis var. israelensis crystal proteins in vivo and in vitro.bacillus thuringiensis var. israelensis crystal proteins were purified by fplc on a mono q column to yield 130, 65, 28, 53, 30-35 and 25 kda proteins. all the purified proteins killed aedes aegypti larvae after citrate precipitation, but the 65 kda protein was the most toxic. a precipitated mixture of 27 and 130 kda proteins was almost as toxic as solubilized crystals. in assays against a range of insect cell lines, the activated form (25 kda) of the 27 kda protein was generally cytotoxic with t ...19883254944
the stegomyia survey and susceptibility status of aedes aegypti to insecticides in calcutta seaport area. 19883256570
pathogenesis of dengue: challenges to molecular biology.dengue viruses occur as four antigenically related but distinct serotypes transmitted to humans by aedes aegypti mosquitoes. these viruses generally cause a benign syndrome, dengue fever, in the american and african tropics, and a severe syndrome, dengue hemorrhagic fever/dengue shock syndrome (dhf/dss), in southeast asian children. this severe syndrome, which recently has also been identified in children infected with the virus in puerto rico, is characterized by increased vascular permeability ...19883277268
dengue and dengue hemorrhagic fever in the americas.there has been a constant increase in the incidence of dengue in the americas over the past 15 years. this has been caused by increased frequency of epidemic activity in most countries, as a result of increased numbers of virus serotypes circulating in the region. the change in disease ecology has resulted in the emergence of dengue hemorrhagic fever/dengue shock syndrome (dhf/dss) in the region, first with a major epidemic in cuba, followed by increased occurrence of sporadic cases of dhf/dss i ...19873313490
dengue in puerto rico: clinical manifestations and management from 1960's to 1987.dengue is a viral disease transmitted by the aedes aegypti mosquito. it is endemic in puerto rico and the caribbean with periodic epidemics occurring at varying intervals. there are three dengue serotypes present in puerto rico, at the present time. the clinical manifestations of dengue in puerto rico are presented from a historical perspective. dengue in puerto rico has evolved from a clinically mild illness in the 1960's to a devastating disease with hemorrhagic manifestations in the 1980's an ...19873313491
dengue haemorrhagic fever in malaysia: a review.the historical background, epidemiology and changing pattern of clinical disease as seen in malaysia is reviewed. the preliminary results of the longitudinal study of epidemiology of dengue in malaysia is also presented. studies led by rudnick et al. over some 18 years have established that the disease is endemically transmitted by both aedes aegypti and aedes albopictus causing illnesses ranging from mild febrile episodes through classical dengue fever, dengue haemorrhagic fever and the dengue ...19873324361
characterization of the toxicity and cytopathic specificity of a cloned bacillus thuringiensis crystal protein using insect cell culture.an insecticidal protein gene from bacillus thuringiensis var. aizawai was cloned in escherichia coli. the cloned gene expressed at a high level and the synthesized protein appeared as an insoluble, phase-bright inclusion in the cytoplasm. these inclusions were isolated by density gradient centrifugation, the isolated protein was activated in vitro by different proteolytic regimes and the toxicity of the resulting preparations was studied using insect cells grown in tissue culture. the inclusions ...19873330756
further characterization of refractoriness in aedes aegypti (l.) to infection by dirofilaria immitis (leidy).factors which control the expression of the refractory or susceptible condition to infection with dirofilaria immitis in the mosquito. aedes aegypti, were investigated using three protocols. (1) microfilariae and prelarvae were injected into the hemocoel of susceptible a. aegypti. some microfilariae and prelarvae developed to the l1 larval stage but they failed to complete development to the infective stage. (2) enema of microfilariae and prelarvae from infected susceptible and refractory donor ...19883366210
fmrfamide- and adipokinetic hormone-like immunoreactivity in the nervous system of the mosquito, aedes aegypti.as demonstrated with immunocytochemistry, specific cells and axons in the nervous system of female aedes aegypti contain antigens immunologically related to fmrfamide (phenylalanine-methionine-arginine-phenylalanine-amide) and locust adipokinetic hormone i (akh). in the supra-esophageal ganglion, including some medial neurosecretory cells, and in all ganglia of the ventral nerve cord, there are 100-120 cells immunoreactive to a fmrfamide antiserum. the same cells cross-react with a bovine pancre ...19883372750
susceptibility & transmissibility of different geographical strains of aedes aegypti mosquitoes to chikungunya virus. 19883397145
[the experimental pathogenic effect of spiroplasma isolated from mosquitoes on the hatching of aedes aegypti ova and the growth of larva hatched from these eggs].the authors did study the experimental effects on aedes aegypti ova of different spiroplasma strains, isolated from mosquitoes in french savoy and in taiwan. the sp7 strain, from armigeres subalbatus (taiwan), demonstrates a true pathogenic effect on the larval evolution, without sex ratio modifications, nor bacterial transmission to the adult mosquitoes. the authors present their results and emphasize the difficult use of spiroplasmas sp.19883400962
properties of a ribonuclease from aedes aegypti larvae.1. the properties of a soluble ribonuclease from aedes aegypti larvae have been compared with ribonuclease activity in adult female tissue. 2. in larval extracts ribonuclease activity was maximal at 40-45 degrees c whereas activity in tissue from adult females was highest at 50 degrees c. 3. ribonuclease activity that was recovered in a 20-60% ammonium sulfate precipitate was further purified by batch elution from deae-sephacel and from carboxymethylcellulose. 4. ribonuclease activity in the par ...19873427905
aedes aegypti and yellow fever virus: the effect of chloroquine on infection and transmission rates. 19873445296
overproduction of detoxifying esterases in organophosphate-resistant culex mosquitoes and their presence in other insects.antisera raised against the denatured polypeptide of two organophosphate-detoxifying esterases (b1 and a1) of culex mosquitoes were used in an immunoblot method to quantify esterase production in resistant versus susceptible strains and to detect the presence of immunologically related proteins in other insects. it was demonstrated that esterase b1 of culex quinquefasciatus and esterase a1 of culex pipiens are overproduced in resistant strains by factors of at least 500-fold and 70-fold, respect ...19873470782
control of aedes aegypti larvae in household water containers by chinese cat fish.in 1980-81 an outbreak of dengue fever occurred in guangdong province and in guangxi-zhuang autonomous region in the central-southern part of china. subsequently, a nationwide survey indicated that the vector of the disease, aedes aegypti, was confined to the coastal strip of guangdong and guangxi-zhuang. since the first case in the outbreak occurred in guangxi-zhuang, a community-based programme to control a. aegypti was set up in eight fishing villages of this region where the mosquito was bre ...19873500803
increased yellow fever virus infection and dissemination rates in aedes aegypti mosquitoes orally exposed to freshly grown virus. 19873503398
a behavioral mechanism for resting site selection by pupae in three mosquito species.pupae of aedes aegypti, ae. triseriatus and culex restuans dive less frequently when resting in a concave meniscus than when resting in open water. they also tend to terminate diving after contacting submerged vertical surfaces, increasing their chances of surfacing in a concave meniscus. as a result pupae tend to rest in concave menisci associated with emergent vertical surfaces, a behavioral adaptation by which they probably conserve energy and avoid predation.19873504897
strategies for the emergency control of arboviral epidemics in new orleans.a study was initiated to evaluate the effectiveness of aerial ulv spraying for the control of aedes aegypti and culex quinquefasciatus as an emergency antiepidemic measure against dengue fever and st. louis encephalitis, respectively. malathion was aerially applied at 219 ml/ha over 344 ha area of the ninth ward in new orleans. laboratory susceptibility tests and field-cage exposures indicated that the target populations were susceptible to malathion and that acceptable coverage of the study are ...19873504901
an alternative bioassay employing neonate larvae for determining the toxicity of suspended particles to mosquitoes.an alternative bioassay using neonate larvae of aedes aegypti is described for determining the toxicity of suspended particles, particularly insecticidal bacteria, to mosquitoes. this new assay is comparable in precision to the 4th instar bioassay recommended by the world health organization, but is quicker and requires much less space. values obtained using neonate larvae as the test insect showed less variation within and between replicates in regard to lc50 and slope of the regression line, a ...19873504908
variation in the vector competence of geographic strains of aedes albopictus for dengue 1 virus.eight geographic strains of aedes albopictus from asia and north america and one north american strain of aedes aegypti were tested for their vector competence with dengue 1 virus. three groups of ae. albopictus were established based on their vector competence: a) the oahu laboratory strain, b) the three malaysian strains, and c) the tokyo and three north american strains. the three north american strains were similar to the strain of ae. aegypti from houston, texas in their ability to transmit ...19873504922
natural transmission of dirofilaria immitis by aedes aegypti.the liverpool strain of the mosquito aedes aegypti was infected with microfilariae of the canine heartworm, dirofilaria immitis, and was used to transmit heartworm larvae to three dogs. methods of confirming heartworm infection in these dogs included the modified knott's test, a commercial enzyme-linked-immunosorbent assay (elisa), an indirect fluorescent antibody (ifa) test, and post-mortem examination.19863507470
evaluation of the cdc gravid trap for the surveillance of st. louis encephalitis vectors in memphis, tennessee.collections with cdc gravid mosquito traps on 954 trap-nights from may through september 1983 are compared to 2,608 concurrent resting site collections made in the same area of memphis, tennessee. gravid traps yielded 88 times more culex per collection and 96 times more culex per man hour. the total gravid trap catch was 135,724 mosquitoes, 99% of which were either culex pipiens or cx. restuans, whereas these species comprised only 63% of the 6,613 mosquitoes collected from resting sites. gravid ...19863507491
effects of sublethal exposure to bacillus thuringiensis var. israelensis on larval development and adult size in aedes aegypti.the effects of exposure to sublethal concentrations of bacillus thuringiensis var. israelensis (serotype h-14) on second instar aedes aegypti larvae were investigated. a test system was developed in which adverse effects would be detected as increased duration of larval development and decreased adult body size. no evidence of negative effects on survivors could be detected when sufficient b.t.i. dosages were applied to kill approximately half of the larvae in the treatment groups. however, when ...19863507506
the perspective of aedes albopictus from the administrative viewpoint.mosquito control administrators should consider a newly introduced species in view of local conditions. aedes albopictus was discovered in harris county while surveying for aedes aegypti. recognizing a potential threat to public health, local and state officials were notified of the discovery. questions posed by the introduction of a foreign species requires a cooperative application of research resources. the centers for disease control (cdc) should serve as the coordinator of this effort.19863507521
toxicity in carcasses of bacillus thuringiensis var. israelensis-killed aedes aegypti larvae against scavenging larvae: implications to bioassay. 19863507532
association of chlamydia trachomatis with mammalian and cultured insect cells lacking putative chlamydial receptors.the association of radiolabelled chlamydia trachomatis (strains dk-20 and 434) with cultured cell monolayers has been examined. previously, n-acetyl neuraminic acid and n-acetyl-glucosamine had been suggested to be involved in the association of certain strains of c. trachomatis with cultured cell monolayers. we have now studied the association of non-lgv (dk-20) and lgv (434) strains of c. trachomatis with cultured cells lacking these putative receptor components. comparison of the association ...19873507553
[the aedes aegypti problem in brazil]. 19873507740
complement effects on the infectivity of plasmodium gallinaceum to aedes aegypti mosquitoes. i. resistance of zygotes to the alternative pathway of complement.gametocytes are the intraerythrocytic stages of malaria parasites that infect mosquitoes. when gametocytes of the chicken malaria parasite plasmodium gallinaceum are ingested by a mosquito they become extracellular in the mosquito midgut, form gametes, and fertilize within 10 to 15 min after the insect has taken a blood meal. gametocytes of p. gallinaceum were infectious when fed to aedes aegypti mosquitoes in blood meals containing native serum from chickens or from the non-host species, man or ...19863517168
bacteriolytic factor in the salivary glands of aedes aegypti.salivary gland homogenates from adult aedes aegypti lyse micrococcus lysodeikticus cells. the bacteriolytic factor is present in a cell type common to both male and female mosquitoes, as well as in the crop of sugar-feeding mosquitoes. the bacteriolytic factor releases digestion products from sacculi of escherichia coli that are different from those of hen egg white lysozyme.19863519067
aedes aegypti mosquitoes in the americas: a review of their interactions with the human population.this paper describes the significant changes in the relationship between aedes aegypti mosquitoes and the human population in the americas from the 1800s to present. first, the history of the arrival of the mosquito, the consequent epidemics of yellow fever and dengue, and the eventual implication of the mosquito as vector is described. second, the pan american health organization's aedes aegypti eradication program is discussed and the potential threat to the americas of development of the deng ...19863532349
expression in escherichia coli of a cloned crystal protein gene of bacillus thuringiensis subsp. israelensis.a ca. 10-kilobase (kb) hindiii fragment of plasmid dna from bacillus thuringiensis subsp. israelensis was cloned into plasmid puc9 and transformed into escherichia coli. extracts of the recombinant strain contained a 27-kilodalton (kda) peptide that reacted with antibodies to a 27-kda peptide isolated from crystals produced by b. thuringiensis subsp. israelensis. extracts of the recombinant strain were hemolytic and toxic to aedes aegypti larvae. full expression of the 27-kda peptide required th ...19873546262
[are sugars always necessary for the infection of mosquitoes with malarial plasmodia?].the possibility of the completion of the sporogony cycle of plasmodium gallinaceum in aedes aegypti mosquitoes, which were not given preliminary carbohydrate feeding, is considered. the significance of the obtained data for tracing the connection between the type of feeding of arthropods and their ability to be specific vectors of agents of transmissible infections is discussed.19873574981
potential for organophosphate resistance in aedes aegypti (diptera: culicidae) in the caribbean area and neighboring countries. 19873585923
a study on susceptibility of indonesia colonies of aedes aegypti and aedes albopictus mosquitoes to experimental infection with dengue type 3 and chikungunya viruses. 19873586577
multiplication of chikungunya virus in salivary glands of aedes albopictus (oahu strain) mosquitoes: an electron microscopic study.aedes albopictus as well as aedes aegypti is an important vector of chikungunya and dengue viruses. electron microscopic observations on the salivary glands of ae. albopictus infected with chikungunya virus were performed in comparing with those of ae. aegypti infected with dengue virus. no virus budding from the cell surface of the chikungunya-infected mosquito's salivary glands was found as shown in dengue-infected ones, in contrast to the findings of the mammalian cells such as vero, kb, imr, ...19863599528
development of brugia malayi and dirofilaria immitis in aedes aegypti: effect of the host's nutrition.the purpose of the study was to establish the importance of single and multiple blood meals taken by a vector in the development of larval filariae, dwelling in tissues other than the fat body. the black eye strain of aedes aegypti was used as experimental vector for brugia malayi and dirofilaria immitis, filariae species which develop in the flight muscles and malphighian tubules respectively. under similar conditions, both filariae species molted for the first time on the 6th day and a second ...19873602836
increased dissemination of dengue 2 virus in aedes aegypti associated with concurrent ingestion of microfilariae of brugia malayi.we investigated whether concurrent ingestion of dengue 2 virus and microfilariae of brugia malayi would increase viral infection and dissemination rates in aedes aegypti. infection rates were similar in mosquitoes that ingested virus alone or both virus and microfilariae concurrently. however, viral dissemination rates, as determined by recovery of dengue virus from both legs and bodies separately, were significantly greater in mosquitoes that ingested both agents concurrently than in those that ...19873605503
purification of the mosquitocidal and cytolytic proteins of bacillus thuringiensis subsp. israelensis.two proteins from parasporal crystals of bacillus thuringiensis subsp. israelensis were purified to electrophoretic homogeneity by gel filtration and anion-exchange chromatography. the larger of the two proteins (molecular weight, 68,000) was not cytolytic, whereas the smaller protein (molecular weight, 28,000) was highly cytolytic when assayed against rat erythrocytes. when these proteins were assayed against larvae of the yellow fever mosquito, aedes aegypti, the larger protein was at least 10 ...19873606108
genetic studies on hexokinase in the mosquito aedes togoi.hexokinases (ec 2.7.1.1) were genetically analyzed in the mosquito aedes togoi by agar gel electrophoresis. enzyme activity was observed anodally in one major banding region (hk-1) on the gel and in another faintly stained region (hk-2). a total of six bands was detected in the hk-1 region. all six bands could be detected in three body parts, head, thorax, and abdomen, of adults with different banding intensities. the third and fourth bands, numbered from the more anodal side, showed the broades ...19873619882
ultrastructural midgut events in culicidae larvae fed with bacillus sphaericus 2297 spore/crystal complex.ingestion of bacillus sphaericus 2297 spore/crystal complex by culicidae larvae anopheles stephensi, culex pipiens subsp. pipiens and aedes aegypti was rapidly followed by a dissolution of the protein crystalline inclusions inside the anterior stomach of the three species. during the first day of intoxication, b. sphaericus spores germinated within the midgut lumen, and were in a vegetative stage between 36-48 h after ingestion when the larvae began to die. ultrastructural observations focused o ...19873663390
absence of transovarial transmission of chikungunya virus in aedes aegypti & ae. albopictus mosquitoes. 19873666861
the problem of aedes aegypti in brazil. 19863685524
seasonal incidence and diel patterns of oviposition in the field of the mosquito, aedes aegypti (l.) (diptera:culicidae) in trinidad, west indies: a preliminary study.diel patterns of oviposition of domestic aedes aegypti in the field in trinidad, west indies were monitored weekly for one year using standard ovitraps. during the wet season (may to november) a large, well defined peak of oviposition (comprising more than 80% of eggs laid) occurred one to two hours before sunset, and a much smaller peak (about 5% of eggs laid) occurred one to two hours after sunrise. during the dry season (december to may) a broad, poorly defined peak (about 36% of eggs laid) f ...19873689024
influence of developing dirofilaria immitis on the spontaneous flight activity of aedes aegypti (diptera: culicidae). 19873694634
selection for resistance to bacillus thuringiensis subspecies israelensis in field and laboratory populations of the mosquito aedes aegypti. 19863701104
the migration of infective larvae of brugia pahangi within the mosquito, aedes aegypti.the course of the migration of infective larvae of brugia pahangi within the mosquito, aedes aegypti, is described. the presence of blood or eggs in the abdomens of mosquitoes at a time when the infective larvae are beginning their migration out of the thorax leads to a significant increase in the proportion of larvae accumulating in the abdomen. the evidence supports the hypothesis that infective larvae may accumulate in the labium as a direct consequence of the insect's internal anatomy i.e. i ...19863714302
defense reactions of mosquitoes to filarial worms: effect of host age on the immune response to dirofilaria immitis microfilariae.the melanization response of aedes aegypti black-eyed liverpool strain (lvp) and aedes trivittatus against intrathoracically inoculated dirofilaria immitis microfilariae (mff) was assessed in mosquitoes less than 1, 14, 21, and 28 days after adult ecdysis. there was a significant decrease in the melanization response of a. aegypti 14 days of age and older at 1, 3, and 5 days postinoculation (pi) compared to less than 1-day-old mosquitoes. the response also was reduced significantly in 14- to 28- ...19863734989
parasite-induced suppression of the immune response in aedes aegypti by brugia pahangi.the melanization response against intrathoracically inoculated brugia pahangi and dirofilaria immitis microfilariae (mff) isolated from vertebrate host blood was evaluated in both uninfected aedes aegypti black-eyed liverpool strain and in mosquitoes harboring a developing b. pahangi infection. the immune response against inoculated mff of either species was significantly reduced by 28-47% in infected as compared with uninfected mosquitoes. attempts to passively transfer this suppression factor( ...19863734990
hemocyte-mediated melanization of microfilariae in aedes aegypti.the melanization response of adult female aedes aegypti (black-eyed liverpool strain) against intrathoracically inoculated dirofilaria immitis microfilariae (mff) was assessed with transmission electron microscopy. the initial reaction involved the lysis of hemocytes at or near the surface of the parasite prior to the deposition of pigment. subsequently, melanin formation was noted in the area of lysed cells and appeared to cascade onto the parasite surface. observations suggest that melanin may ...19863734991
influence of developing brugia pahangi on spontaneous flight activity of aedes aegypti (diptera: culicidae). 19863735352
fmrfamide- and pancreatic polypeptide-like immunoreactivity of endocrine cells in the midgut of a mosquito.immunocytochemical surveys of midguts from female mosquitoes, aedes aegypti, reveal that half of the estimated 500 endocrine cells in a midgut contain a substance recognized by antisera to bovine pancreatic polypeptide and a molluscan peptide, fmrfamide (phenylalanine-methionine-arginine-phenylalanine-amide). with light microscopy the cells resemble an endocrine type because of their basal position in the epithelium, conical shape, and, in some instances, apical extensions to the lumen. at the u ...19863738889
trichostrongylus colubriformis: isolation and characterization of ovicidal activity from bacillus thuringiensis israelensis.bioassay of media fractions from cultivation of bacillus thuringiensis israelensis revealed that ovicidal activity for eggs of the ruminant nematode trichostrongylus colubriformis was found in microbial crystals, but was not released into culture medium. the purified delta-endotoxin of b. t. israelensis, composed of two 25 kda proteins, had no effect on nematode eggs. a fraction that had high ovicidal activity for eggs of t. colubriformis was isolated by high performance liquid chromatography fr ...19863743716
the ability of aedes aegypti mosquitoes to survive and transmit infective larvae of brugia pahangi over successive blood meals.the mortality of aedes aegypti mosquitoes increased; immediately following a blood meal containing microfilariae of brugia pahangi, when infective larvae began to migrate out of the flight muscles and when infective larvae were lost from the mosquitoes during a blood meal. when infective mosquitoes took a second blood meal 86.2% of the infective larvae escaped from their bodies. however, only 50.3% escaped when mosquitoes fed through a thin layer of cotton. infective larvae in the abdomen of the ...19863745870
etiologic and serologic investigations of the 1980 epidemic of dengue fever on hainan island, china.virologic and seroepidemiologic studies were carried out during an epidemic of dengue fever on hainan island in 1980. dengue 3 virus was isolated from 46 of 77 acute phase sera and from 1 of 10 pools of adult aedes aegypti. dengue 1 virus virus was isolated from a single acute phase serum. seroepidemiologic investigations showed that 74% of healthy individuals in the epidemic area had antibody to dengue virus compared to 54% in an area where epidemic dengue had occurred in 1978, and less than or ...19863766851
comparative studies on the melanization response of male and female mosquitoes against microfilariae.the melanization response of adult male and female aedes trivittatus and the black-eyed liverpool strain of aedes aegypti against intrathoracically inoculated dirofilaria immitis microfilariae (mff) was assessed at 1, 3, and 5 days postinoculation (pi). the melanization reaction of males is significantly less effective than the response elicited by female mosquitoes. no mff in male a. aegypti and only 17% of mff recovered from a. trivittatus were fully melanized by day 5 pi compared with 80% and ...19863770266
analysis of mosquito larvicidal potential exhibited by vegetative cells of bacillus thuringiensis subsp. israelensis.vegetative bacillus thuringiensis subsp. israelensis cells (6 x 10(5)/ml) achieved 100% mortality of aedes aegypti larvae within 24 h. this larvicidal potential was localized within the cells; the cell-free supernatants did not kill mosquito larvae. however, they did contain a heat-labile hemolysin which was immunologically distinct from the general cytolytic (hemolytic) factor released during solubilization of b. thuringiensis subsp. israelensis crystals. the larvicidal potential of the vegetat ...19863777922
ultrastructure of malpighian tubules of aedes aegypti infected with dirofilaria immitis. 19863782853
the effect of repeated blood meals on the larval development of dirofilaria corynodes in the fat body of aedes aegypti.the objective of the study was to determine whether blood meals taken by a vector subsequent to the infective one have any influence on the course of development of a filarial parasite in its tissue. the filaria dirofilaria corynodes (von linstow, 1899) was selected for study and the black-eye strain of aedes aegypti served as the experimental vector. the microfilaria of d. corynodes develops to the infective stage in the fat bodies of the vector. following an infective blood meal, mosquitoes we ...19863787121
dispersal and other population parameters of aedes aegypti in an african village and their possible significance in epidemiology of vector-borne diseases.dispersal of aedes aegypti aegypti adults within shauri moyo, an african village in the rabai area north of mombasa, kenya, was studied using the mark-release-recapture method. a total of 920 mosquitoes were captured and uniquely marked, of which 828 (90%) were released and 332 (40%) recaptured. a great majority of mosquitoes were recaptured once, but some individuals were recaptured up to 10 times. most females visited 1 or 2 houses (40.8%, 44.9%, respectively), but there were females that visi ...19863789275
passage of yellow fever virus: its effect on infection and transmission rates in aedes aegypti.the effect of successive lytic passage of yellow fever virus on mosquito infection and transmission rates in the vector, aedes aegypti, was determined. three strains of yellow fever virus from trinidad and peru were passaged five times in suckling mouse brains and seven times in bhk-21 cells. mosquitoes were fed meals containing passaged and unpassaged viruses and infection and transmission rates were compared. rates were similar for all but one of the three virus strains grown in both substrate ...19863789277
surface changes on brugia pahangi microfilariae and their association with immune evasion in aedes aegypti. 19873794383
microfilarial perforation of the midgut of a mosquito.to determine whether the midgut envelope of mosquitoes is disrupted by the passage of microfilariae, ultrastructural changes induced by microfilariae of brugia malayi were observed in midguts of aedes aegypti mosquitoes. basal and apical plasma membranes were destroyed, disrupting the full depth of the midgut wall. ingested ferritin lay against the gut wall, suggesting absence of the peritrophic membrane during penetration. exsheathment of microfilariae appears to be enhanced by movement against ...19863806321
effect of temperature on the vector efficiency of aedes aegypti for dengue 2 virus.the effect of temperature on the ability of aedes aegypti to transmit dengue (den) 2 virus to rhesus monkeys was assessed as a possible explanation for the seasonal variation in the incidence of dengue hemorrhagic fever in bangkok, thailand. in two laboratory experiments, a bangkok strain of ae. aegypti was allowed to feed upon viremic monkeys infected with den-2 virus. blood-engorged mosquitoes were separated into two groups and retained at constant temperatures. virus infection and transmissio ...19873812879
hemocyte cell surface changes in aedes aegypti in response to microfilariae of dirofilaria immitis.this study involved the assessment of surface changes on hemocytes of aedes aegypti black-eyed liverpool strain in association with the melanization response against intrathoracically inoculated dirofilaria immitis microfilariae (mff). surface changes on hemocytes were identified using fluorescein-labeled wheat germ agglutinin (wga). in mosquitoes eliciting a melanization response against inoculated mff, there was a 5-fold increase in the percentages of hemocytes exhibiting wga binding compared ...19863819964
effect of plasmodium gallinaceum infection on the mortality and body weight of aedes aegypti (diptera: culicidae). 19873820241
avermectins, mk-933 and mk-936, for mosquito control.two avermectins were shown to be effective as mosquito larvicides or when fed to adult female mosquitoes in sucrose solution or in blood. larval lc50 values of compounds mk-933 and mk-936, expressed as parts per billion, were found to be 3.94 and 2.42 for culex pipiens, 5.85 and 2.90 for anopheles stephensi and 23.4 and 10.4 for aedes aegypti. when fed to adult females of an. stephensi, ae. aegypti or cx quinquefasciatus, mk-933 at 2.8mg active ingredient per litre in sucrose solution caused com ...19853832491
oral infection of aedes aegypti with yellow fever virus: geographic variation and genetic considerations.twenty-eight populations representing a worldwide distribution of aedes aegypti were tested for their ability to become orally infected with yellow fever virus (yfv). populations had been analyzed for genetic variations at 11 isozyme loci and assigned to one of 8 genetic geographic groups of ae. aegypti. infection rates suggest that populations showing isozyme genetic relatedness also demonstrate similarity to oral infection rates with yfv. the findings support the hypothesis that genetic variat ...19853834804
selection for susceptibility and refractoriness of aedes aegypti to oral infection with yellow fever virus.artificial selection on strains of aedes aegypti showing susceptibility and refractoriness to oral infection with yellow fever virus (yfv) suggests that there is a significant genetic component to this trait. using a population with an average susceptibility of 15%, inbreeding of isofemale lines followed by individual selection produced susceptible (29% infected) and refractory (11% infected) lines. the difference between lines was largely apparent before individual selection, which failed to in ...19853834805
rainfall, abundance of aedes aegypti and dengue infection in selangor, malaysia.an epidemio-meteorotropic analytical study of selangor, in the southwest coast of peninsular malaysia, examines the monthly incidence of dengue for the period 1973-1982 to assess possible quantitative association with the monthly rainfall. the relationships between rainfall, abundance of a. aegypti and dengue infection during 1982 in jinjang, a dengue-prone area in selangor, were also examined. a quantitative association between rainfall and the number of dengue cases was found during the first ...19853835698
[new data on the transmission of filariae].this paper summarizes research of the past several years on two phases of filarial transmission: the ingestion of microfilariae by the vector and the regulation of the percentage of successful parasites by the vector. experiments involved several different models for study: injection of inert particles into the bloodstream of a rodent and their subsequent ingestion by a vector; ingestion of gametocytes of different ages by vectors of a rodent malaria; and a monkey simultaneously infected with fo ...19853836764
aedes aegypti: model for blood finding strategy and prediction of parasite manipulation.aedes aegypti mosquitoes salivate during intradermal probing of vertebrate prey before ingesting blood (griffiths and gordon 1952). nonsalivating mosquitoes locate blood more slowly; this difference was ascribed to an anti-platelet activity found in the mosquito's saliva (ribeiro et al. 1984). mosquitoes infected with plasmodium gallinaceum suffer pathology that specifically impairs saliva anti-hemostatic activity but without reducing volume of output (rossignol et al. 1984). the complexity of t ...19853839460
[present viability of the eradication of aedes aegypti in the control of yellow fever in brazil]. 19853843131
geographic genetic differentiation and arbovirus competency: aedes aegypti and yellow fever. 19853870635
a simple method of identifying organophosphate insecticide resistance in adults of the yellow fever mosquito, aedes aegypti.a simple filter paper spot test is described for identifying adult aedes aegypti resistant to malathion as a result of raised esterase levels. the method is compared with established polyacrylamide gel (pag) electrophoresis techniques for determining esterase-6 activity, and its applicability as a field test is discussed.19853880211
laboratory evaluation of controlled-release insect repellent formulations.seven microcapsule formulations and two polymer formulations of deet were tested on white rabbits for their repellency against the mosquito, aedes aegypti. two microcapsule formulations and one polymer formulation provided more than 80% protection for 12 hours. results demonstrated that the protection period of deet can be extended through controlled-release techniques.19853880224
development of dirofilaria immitis third stage larvae (nematoda: filarioidea) in micropore chambers implanted into surrogate hosts.groups of 100 third stage larvae of dirofilaria immitis recovered from aedes aegypti were loaded into 250 microliters capacity micropore chambers (0.3 micron pore size) and implanted into the peritoneal cavity of mice, jirds, cotton rats and ferrets. in all hosts 74-87% of larvae moulted by 74 hours, with less than 5% mortality. the fourth stage worms recovered at 74 hours were cultured in vitro in l-15 (leibovitz) medium plus 20% foetal bovine serum with a dog sarcoma feeder cell line. after 96 ...19853890119
viability of mycobacterium leprae within the gut of aedes aegypti after they feed on multibacillary lepromatous patients: a study by fluorescent and electron microscopes. 19853908862
development of mansonella ozzardi in the liverpool strain of aedes aegypti. 19853914123
isolation of a relatively nontoxic 65-kilodalton protein inclusion from the parasporal body of bacillus thuringiensis subsp. israelensis.ultrastructural studies of the mosquitocidal bacterium bacillus thuringiensis subsp. israelensis revealed that the parasporal body contained three major inclusion types, designated types 1, 2, and 3, which could be differentiated on the basis of electron opacity and size and, to some extent, shape. the type-2 inclusion, which was of moderate electron density and often appeared as a bar-shaped polyhedral body, was isolated on nabr gradients from purified parasporal bodies and characterized by sod ...19863944061
increased biting rate and reduced fertility in sporozoite-infected mosquitoes.because salivary function and blood location are impaired in sporozoite-infected mosquitoes, we determined whether such pathology also could lead to an increased biting rate. for 5 days, we compared relative daily biting rates of plasmodium gallinaceum sporozoite-infected mosquitoes (aedes aegypti) and noninfected mosquitoes with an olfactometer. mosquitoes then were exposed for 5 min to an anesthetized guinea pig. infected mosquitoes exhibited a significant increase in olfactometer response whi ...19863953943
mechanical transmission of rift valley fever virus by hematophagous diptera.experimental studies were conducted to determine if hematophagous diptera were capable of mechanical transmission of rift valley fever (rvf) virus to laboratory animals. all species tested (glossina morsitans, aedes aegypti, aedes taeniorhynchus, culex pipiens, stomoxys calcitrans, lutzomyia longipalpis, and culicoides variipennis) mechanically transmitted the virus to hamsters. mechanical transmission rates for g. morsitans ranged from 0-100%, with the probability of mechanical transmission pos ...19853970308
plasmodium gallinaceum: sporozoite activity in immune mosquito hemolymph.sporozoites of plasmodium gallinaceum are relatively inactive in hanks' balanced salt solution or in the hemolymph of the susceptible aedes aegypti mosquito. they become agitated and very active in the presence of the hemolymph of the innately immune mosquito, culex pipiens. sporozoites from the latter are more infective in chicks than the former. this behavior is likely the result of stimulation or irritation by the adverse environment.19853972059
characterization of refractoriness in aedes aegypti (diptera: culicidae) to infection by dirofilaria immitis. 19853981554
[sensitivity of aedes aegypti infected with the malaria agent to ddt]. 19853990637
the effect of different types of skin surfaces on the transmission of brugia pahangi infective larvae by the mosquito aedes aegypti.the transmission of brugia pahangi from aedes aegypti into meriones unguiculatus was compared for four different skin surfaces (hairy, cloth, clean, greasy). unshaven jirds reduced the feeding avidity of infective mosquitoes. the loss of larvae from infective mosquitoes was greatest when these insects fed on "exposed" skin surfaces. significantly fewer infective larvae penetrated the host when infective mosquitoes fed on a jird through a thin layer of cloth.19853992643
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