PMID(sorted descending)
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
changes in ribonuclease activity during development of the mosquito, aedes the mosquito aedes aegypti, quantitative and qualitative changes have been detected in ribonuclease activity during development. ribonuclease activity is particularly high in extracts from larvae, relative to that in extracts from pupae or adults. larval extract is enriched for a ribonuclease that is heat-labile, has an alkaline ph optimum, and is extremely sensitive to the divalent cation, manganese. extract from adult females is enriched for a heat-stable component that has an acidic ph opt ...19863743028
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
influence of developing brugia pahangi on spontaneous flight activity of aedes aegypti (diptera: culicidae). 19863735352
ultrastructural organization of spermatocysts in the testes of aedes aegypti (diptera: culicidae). 19863735341
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
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
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
improved development of brugia microfilariae following cryopreservation in liquid nitrogen using a technique suitable for field conditions.a technique for improved cryopreservation at -196 degrees c of brugia spp. microfilariae has been developed by modifications of a procedure previously used with onchocerca spp. a double incubation in ethanediol (ed) solutions, firstly at 37 degrees c in 10% (v/v) ed for 15 min and secondly at 0 degrees c in 40% (v/v) ed for 45 sec followed by plunging into liquid nitrogen, resulted in over 90% of the microfilariae of b. malayi exhibiting normal motility. when used with b. pahangi microfilariae, ...20133726977
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
selection for resistance to bacillus thuringiensis subspecies israelensis in field and laboratory populations of the mosquito aedes aegypti. 19863701104
influence of developing dirofilaria immitis on the spontaneous flight activity of aedes aegypti (diptera: culicidae). 19873694634
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
the problem of aedes aegypti in brazil. 19863685524
absence of transovarial transmission of chikungunya virus in aedes aegypti & ae. albopictus mosquitoes. 19873666861
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
linkage relationships between a low-mobility esterase locus and group i markers in larvae of the yellow fever mosquito, aedes aegypti (diptera: culicidae). 19873625727
life cycle and mode of infection of leptolegnia chapmanii (oomycetes) parasitizing aedes aegypti. 19873624894
genetic studies on hexokinase in the mosquito aedes togoi.hexokinases (ec 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
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
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
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
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
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
potential for organophosphate resistance in aedes aegypti (diptera: culicidae) in the caribbean area and neighboring countries. 19873585923
inheritance of ddt dehydrochlorination and of a mechanism restricting uptake of ddt in the mosquito aedes aegypti.crosses and backcrosses were made between the t8 dichlorodiphenyltrichloroethane (ddt) resistant strain and ns susceptible strain. each generation was tested for resistance, for internal levels of ddt and dichlorodiphenyldichloroethylene (dde) (thus "ddt uptake" (ddt + dde) and percentage ddt dehydrochlorination in vivo), and for ddt dehydrochlorination in vitro, both at the larval and adult stages. the patterns of inheritance of uptake and dehydrochlorination were different. at both life stages ...19873582976
multiple forms of cerebral peptides with steroidogenic functions in pupal and adult brains of the yellow fever mosquito, aedes the adult mosquito, aedes aegypti, the cerebral egg development neurosecretory hormone (ednh) regulates reproduction by activating the ovaries to synthesize the steroid hormone ecdysone, while during postembryonic development the cerebral prothoracicotropic hormone (ptth) activates the prothoracic glands to synthesize ecdysone. in each case, ecdysone than drives stage-specific physiological processes. since ednh and ptth share a common steroidogenic function, it is conceivable that they are s ...19873582726
the impact of sequential ultra-low volume ground aerosol applications of malathion on the population dynamics of aedes aegypti (l.).the efficacy of sequential, ultra-low volume ground aerosol applications of malathion at current u.s. label rates was evaluated as an emergency control measure for adult populations of aedes aegypti (l.) in new orleans, louisiana. replicates of 11 sequential aerosol treatments applied 12 hr apart during a 5.5-day period reduced mean adult captures and oviposition rates during the treatment period 73% and 75%, respectively. we hypothesize that oviposition was not completely suppressed because fem ...19873578659
[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
ribosome metabolism during the vitellogenic cycle of the mosquito, aedes aegypti.ribosome accumulation and synthesis in the fat body of the mosquito aedes aegypti increased by approx. 4-fold during 18 h after the blood meal, consistent with the pattern of total rna accumulation during the synthetic phase of the vitellogenic cycle. by 24-30 h after the blood meal, the accumulated ribosomes began to be degraded, and the total rna content in the fat body eventually returned to previtellogenic levels. a method has been developed for isolation of ribosomal subunits from fat body, ...19873567223
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
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
mosquito trypsin: immunocytochemical localization in the midgut of blood-fed aedes aegypti (l.).a polyclonal antibody was raised against trypsin purified from the midgut of blood-fed aedes aegypti. using this antibody and our modification of the peroxidase-antiperoxidase immunocytochemical reaction, strong activity was found in the lumen of the midgut at the light-microscopical level. the activity was localized mainly in the posterior part of the distensible, abdominal midgut, along the periphery of the blood bolus and within the peritrophic membrane. immunoreactivity appeared 8 h after th ...19863524850
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
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
the vitellogenin gene family of aedes aegypti.we have been interested in identifying genes that play a role in reproduction of the mosquito aedes aegypti. our interests are currently focused on the vitellogenin genes which in the mosquito are expressed only in the fat body in response to the insect steroid hormone, 20-hydroxyecdysone. four of the five vitellogenin genes in the genome have been cloned. we have examined the relationships between these genes and find that they form a small gene family exhibiting different levels of relationshi ...19873509110
[the aedes aegypti problem in brazil]. 19873507740
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
toxicity in carcasses of bacillus thuringiensis var. israelensis-killed aedes aegypti larvae against scavenging larvae: implications to bioassay. 19863507532
a model for polygenic inheritance of abdominal tergal scale pattern in aedes aegypti.there is much variation in the amount of white scaling on the abdominal tergites of aedes aegypti. the genetic basis for this white scale pattern was investigated in two laboratory strains established by selection from the carn strain of ae. aegypti. these experimental strains were crossed in all possible directions in single pair matings. based on analysis of their progeny it is proposed that genes at three separate independently assorting loci control abdominal tergal scale pattern. correlatio ...19863507526
laboratory and field studies with 32p labeled toxorhynchites rutilus rutilus.females and eggs of toxorhynchites r. rutilus were labeled with 32p by feeding fourth-stage larvae 32p labeled aedes aegypti larvae. eggs from females up to 3 weeks in age had detectable levels of radioactivity and individual eggs contained ca. 0.3% of the mother's total radioactivity. comparisons of labeled and unlabeled females in indoor and outdoor cage tests indicated that survival and fecundity of the 2 groups were approximately equal. no differences were noted for dispersal and fecundity o ...19863507524
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 of pyrethroids to aedes aegypti larvae in relation to temperature.the influence of temperature on the toxicity of the pyrethroids cypermethrin, permethrin, fenvalerate, d-phenothrin, flucythrinate and bioallethrin to 3rd instar aedes aegypti larvae was determined. based on lc50 levels, the toxicities of all pyrethroids were in the range of 1.33- to 3.63-fold greater at 20 degrees c than at 30 degrees c. our laboratory results suggest that for larval control of ae. aegypti, field performance of these pyrethroids may be reduced at warmer temperatures.19863507510
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
effect of three pyrethroids on blood feeding and fecundity of aedes aegypti.caged aedes aegypti were exposed to a range of concentrations of d-phenothrin, d-allethrin and tetramethrin in a wind tunnel. mortality, blood engorgement and egg production among these mosquitoes and their progeny were recorded. tetramethrin was the most effective (lc50 of 0.0017%), followed by d-phenothrin (lc50 0.0031%) and d-allethrin (lc50 0.01%). blood engorgement was decreased by treatment with each pyrethroid at the high concentration (0.002%, 0.003% and 0.01% respectively). treatment wi ...19863507504
a laboratory study of cyromazine on aedes aegypti and culex quinquefasciatus and its activity on selected predators of mosquito a laboratory study, the insect growth regulator, cyromazine, exerted a high level of biological activity on aedes aegypti and culex quinquefasciatus treated in the 4th larval instar. at 1.5 and 1.0 ppm this igr produced 97 and 99% inhibition of emergence in adult ae. aegypti, respectively. in cx. quinquefasciatus, there was 99% inhibition at 1 ppm and complete inhibition at 1.5 ppm. the overall pupal mortality was higher than larval or adult stages of both species. this material induced diffe ...19863507502
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
aedes aegypti larvae in portsmouth, rhode island. 19863507481
the size of emerging and host-seeking aedes aegypti and the relation of size to blood-feeding success in the field.the average wing length of aedes aegypti females collected as pupae was 2.47 mm, which was significantly smaller than the 2.64 mm average wing length of the host-seeking females collected in the field. the average wing length of nulliparous host-seeking females was 2.62 mm, which was significantly smaller than the 2.76 mm wing length of parous host-seeking females. thus, small ae. aegypti females exhibited reduced blood-feeding success and, most likely, reduced survival when compared with large ...19863507471
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
the genetic basis of resistance and sensitivity to the meiotic drive gene d in the mosquito aedes aegypti l.a study has been made on the genetic basis of meiotic drive at the distorter (d) locus which, in coupling with the male-determining gene (or region) m on the y chromosome, causes production of excess male progeny. its effect is regulated by the sensitivity/resistance of the x chromosome. this study demonstrates that there are two major loci controlling resistance/sensitivity to md: (1) the m gene (or region) on the x chromosome (allelic with m) which may be either mr or ms (resistant or sensitiv ...19873505880
factors affecting the acquisition of plagiorchis noblei (trematoda: plagiorchiidae) metacercariae by larvae and pupae of aedes aegypti in the laboratory.when exposed to concentrations of less than one plagiorchis noblei cercariae per cc of water, the acquisition of metacercariae by aedes aegypti larvae increased significantly with each successive instar but declined precipitously upon pupation. thus, 1st instar larvae acquired no metacercariae, whereas 4th instars had a mean abundance of 6.15: pupae only acquired a mean of 0.62 parasites. parasite acquisition was largely a function of host size and activity. other factors, such as grooming and f ...19873504947
the origin and movement of gas during adult emergence in aedes aegypti: an hypothesis.several events which precede adult emergence in aedes aegypti were studied, including changes in buoyancy, changes visible through the pupal cuticle and changes at the foregut-midgut junction. our data suggest tht the gas which is present in the posterior midgut at the time of emergence originates in the tracheal system. during the process of emergence this gas moves into the exuvial space through the adult spiracles and then follows the exuvial fluid into the alimentary canal.19873504927
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
susceptibility of aedes aegypti and anopheles quadrimaculatus larvae to infection with the cercariae of plagiorchis noblei (trematoda: plagiorchiidae).the impact of interspecific behavioral differences on the relative susceptibility of third instar aedes aegypti and anopheles quadrimaculatus larvae to infection with cercariae of plagiorchis noblei was determined. when permitted to move freely in a column of water, larvae of ae. aegypti were significantly more susceptible to infection with the parasite than were an. quadrimaculatus larvae. this difference is ascribed to the significantly greater activity of ae. aegypti larvae in the water colum ...19873504909
an alternative bioassay employing neonate larvae for determining the toxicity of suspended particles to 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
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
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
increased yellow fever virus infection and dissemination rates in aedes aegypti mosquitoes orally exposed to freshly grown virus. 19873503398
control of aedes aegypti larvae in household water containers by chinese cat 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
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
[development and basic properties of the viral preparation viroden].laboratory studies demonstrated the effectiveness of viroden preparation in different doses against preimago stages of aedes aegypti mosquitoes. after treatment of larvae of instar 1 at preimago stages about 77% of the insects died. the preparation is stable on storage and resistant to unfavourable environmental factors: sun radiation, heating, ph variations, without significant loss of activity. the study of the host range of densonucleosis virus, the active principle of the viroden preparation ...20163445591
aedes aegypti and yellow fever virus: the effect of chloroquine on infection and transmission rates. 19873445296
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
defense reactions by larvae of aedes aegypti during infection by the aquatic fungus lagenidium giganteum (oomycete).the adherence of zoospores of lagenidium giganteum to the cuticle of mosquito larvae is the initial step in the infection process. subsequently, a germ tube penetrates the integument, inducing a rapid melanization of the injured cuticle and epidermis. after entering the hemocoel the developing hyphae are occasionally encapsulated locally. this process is slow (6 to 12 h postincubation) and most frequently cell-free, although it can be mediated by circulating hemocytes. sporadic hemocyte mediatio ...19883416342
[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
susceptibility & transmissibility of different geographical strains of aedes aegypti mosquitoes to chikungunya virus. 19883397145
categorization of domestic breeding habitats of aedes aegypti (diptera: culicidae) in northern queensland, australia. 19883392713
reexamination of chemically mediated oviposition behavior in aedes aegypti (l.) (diptera: culicidae). 19883392710
time and site of assembly of the peritrophic membrane of the mosquito aedes aegypti.we determined the time and site of secretion of the precursors of the peritrophic membrane (pm) in aedes aegypti and when the structure is assembled. the fine structure of the developing membrane of blood-feed females was described, and the pattern of secretion of injected tritiated glucosamine analyzed autoradiographically. immediately following blood feeding, ingested red cells rapidly become compressed, such that the surrounding plasma is extruded to the margin of the midgut contents. thereby ...19883383223
pathogenesis of the hyphomycete tolypocladium cylindrosporum in the mosquito aedes aegypti. 19883373005
fmrfamide- and adipokinetic hormone-like immunoreactivity in the nervous system of the mosquito, aedes 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
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
a decrease in cysteine levels causes the glutathione deficiency of aging in the mosquito.our previous results indicated that a glutathione (gsh) deficiency is a determinant of the aging process in many tissues and organisms. correction of this deficiency in the aging mosquito by feeding the cysteine (cys) precursor magnesium thiazolidine carboxylic acid (mgtc) suggested that the cause could be a lack of cys. adult mosquitoes (aedes aegypti) were fed either a control diet or a diet supplemented with mgtc and then were analyzed for their cys, cystine, gsh, and glutathione disulfide co ...19883340632
characterization of the toxicity and cytopathic specificity of a cloned bacillus thuringiensis crystal protein using insect cell 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
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
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 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
monoclonal antibodies as probes for processing of the mosquito yolk protein; a high-resolution immunolocalization of secretory and accumulative pathways.a library of monoclonal antibodies (mab) directed against yolk polypeptides of the mosquito aedes aegypti was utilized to visualize the secretory pathway of these polypeptides in the fat body and their accumulative pathway in developing oocytes. single and double immunolabelling using mabs and colloidal gold of different sizes confirmed biochemical observation that 200 +/- 5 and 65 +/- 3 kda polypeptides represent subunits of the yolk protein. this immunocytochemical analysis showed that, in tro ...19873307021
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
the stegomyia survey and susceptibility status of aedes aegypti to insecticides in calcutta seaport area. 19883256570
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
[toxic effects of bacillus thuringiensis var. kurstaki to the immature stage of aedes aegypti]. 19883244164
[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
[susceptibility of aedes aegypti l. mosquitoes infected with an entomopathogenic virus to malarial plasmodia]. 19883231163
phenotypic variability and heterozygosity at an esterase locus in the mosquito aedes aegypti.populations of the yellow fever mosquito, aedes aegypti l. are polymorphic for esterase alleles. this could be because the alleles are neutral or because selection protects the polymorphism, as had been concluded from a study of allele frequencies. a test has been carried out to look for possible associations of esterase heterozygosity with speed of development, body size and spine number symmetry in two spine rows. heterozygotes were found to be larger and slower growing than homozygotes, but t ...19883230031
phototaxis in aquatic invertebrates: possible use in ecotoxicity tests.a series of experiments has been carried out aimed at (i) a deeper study of the phototaxis of some aquatic invertebrates and (ii) its possible use in ecotoxicity tests. for the first point the phototaxis of the nauplii of artemia salina was examined: through tests carried out under different conditions, it was observed that a marked complex response to light existed, which led to a subdivision between individuals with different phototactic response, mainly depending on the density of the nauplii ...19883229377
the collection of aedes aegypti and ae. albopictus from baltimore, maryland. 19883199132
mosquito repellents: monocarboxylic esters of aliphatic diols.selected monocarboxylic esters of aliphatic diols that contained an alicyclic group in the acyl portion of the molecule were effective repellents for aedes aegypti, anopheles quadrimaculatus and an. albimanus when tested on cloth. although 25 of the esters provided greater than 21 days of protection against all 3 species, the repellent potency of the 143 hydroxyesters that were tested was found to vary with mosquito species. anopheles quadrimaculatus was especially susceptible to this type of st ...19883199120
efficacy of two formulations of bacillus thuringiensis var. israelensis (h-14) against aedes vexans and safety to non-target 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
feeding behavior of aedes aegypti larvae and toxicity of dispersed and of naturally encapsulated bacillus thuringiensis var. israelensis. 19883198932
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
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
effects of larval nutrition on the host-seeking behavior of adult aedes aegypti 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
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
toxicity of bacillus sphaericus crystal toxin to 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
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
[determination of the efficacy of repellent preparations in relation to the feeding behavior of aedes aegypti and aedes togoi mosquitoes]. 20093173249
[effect of the viral preparation viroden on aedes aegypti l. mosquitoes in an experiment]. 20093173248
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
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