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[scanning microscopical observations on the foregut structures o mosquitoes and their role for the ingestion of microfilariae (author's transl)].experiments on the transmission of brugia malayi by various mosquitoes had shown that microfilariae ingested by some species were badly damaged when they reached the stomach, but were much less hurt in others. the structures of the foregut likely to cause these injuries, were investigated and documented by scanning microscope techniques. in anopheles albimanus, a. arabiensis, a. stephensi and a. pharoensis which have well developed armatures the microfilariae showed a high rate of destruction. i ...197944040
toxicity of parasporal crystals of bacillus thuringiensis subsp. israelensis to mosquitoes.toxicity of bacillus thuringiensis subsp. israelensis (onr-60a/who 1897) parasporal crystals to three medically important mosquito larvae is described. the numbers of larvae killed are in relation to crystal dry weight. the crystals are lethally toxic to aedes aegypti linnaeus (mean 50% lethal concentration [lc50] = 1.9 x 10(-4) micrograms/ml), culex pipiens var. quinquefasciatus say (lc50 = 3.7 x 10(-4) micrograms/ml), and anopheles albimanus wiedemann (lc50 = 8.0 x 10(-3) micrograms/ml). purfi ...197944177
morphologic variants of anopheles albimanus and susceptibility to plasmodium vivax and p. falciparum.three morphologically different, true-breeding phenotypes have been isolated from a strain of anopheles albimanus from lake apastepeque, el salvador. studies with coindigenous strains of plasmodium vivax and p. falciparum show that these phenotypes differ significantly in their susceptibility to malaria parasites. this difference is apparent both in the number of mosquitoes that become infected and the level of infection obtained. variations in malaria susceptibility are markedly greater with p. ...1977329696
genetic method for the preferential elimination of females of anopheles albimanus.recent field experiments demonstrated the possibility of using the sterile male method for the control of anopheles albimanus wiedemann, the most important vector of human malaria in central america. until now there was no practical method for excluding females from the releases of sterile males. a genetic method was developed for the preferential elimination of females during any of the four life stages. this genetic sexing system utilizes propoxur (o-isopropoxyphenyl methyl-carbamate) suscepti ...1978663614
release of romanomermis culicivorax for the control of anopheles albimanus in el salvador i. mass production of the nematode.the mosquito parasite, romanomermis culicivorax, was mass produced for the treatment of 144,000 m2 of anopheles albimanus breeding area in el salvador. the production of the necessary inoculum required the exposure of 1.6 x 10(6) first-instar culex p. quinque-fasciatus larvae to 137 x 10(6) preparasites (1:14 ratio) each week for 6 weeks. the method employed produced an average 13.7 g (ca. 2,200/g) of postparasitic nematodes per rearing tray (20,000 mosquitoes), a total of 6,392 g (14.1 lb) for ...1978727330
release of romanomermis culicivorax for the control of anopheles albimanus in el salvador ii. application of the nematode.the mosquito breeding area of lake apastepeque, el salvador, was treated 11 times over a 7-week period with romanomermis culicivorax to control anopheles albimanus and an. p. pseudopunctipennis. parasitism averaged 58% but varied greatly from treatment to treatment and from site to site. however, three applications made during evening hours to avoid wind and wave action on the lake produced an average 86% parasitism. no significant differences in susceptibility to r. culicivorax were found betwe ...1978727331
studies on human malaria in aotus monkey. vii. comparative infectivity of two strains of plasmodium vivax to to anopheles freeborni, a. maculatus, and for strains of a. albimanus.a strain of plasmodium vivax from el salvador was shown to be more infectious to the apastepeque strain of anopheles albimanus from el salvador than was a strain of p. vivax from colombia, s. a. the apastepeque mosquito strain was also more susceptible to the savadoran strain of p. vivax than were 2 other strains of this mosquito from el salvador. a strain of a. albimanus from panama was more susceptible to both of the parasite than were any of the salvadoran strains of a. albimanus.1976817008
a prospective study of the effects of ultralow volume (ulv) aerial application of malathion on epidemic plasmodium falciparum malaria. iv. epidemiologic aspects.in the miragoane valley of haiti a consistent pattern in the incidence of plasmodium falciparum malaria over a 10-year period made it possible to predict an annual outbreak and perform a prospective study to test the effects of aerial ultralow volume (ulv) malathion on epidemic levels of this disease. at the end of october 1972, after epidemic levels (100 cases/month/10,000 population) had been reached, spray operations were begun. the first spray cycle produced a sharp and immediate drop in pop ...19751091170
natural infections of anopheles albimanus with plasmodium in a small malaria focus.entomologic surveys conducted in a small village in an area of known high malaria transmission in el salvador yielded a high rate of infection in anopheles albimanus collected inside houses in which cases of malaria had occurred. of 324 specimens dissected, 12 were found to harbor sporozoites or oocysts. this is in contrast to prior reports of extremely low infection rates in collections of this species from malarious areas, and suggests that under some circumstances a. albimanus does meet the c ...19751098498
results of spraying with ultra-low-volume malathion at ground level in panama city.several ultra-low-volume (ulv) sprayings of technical malathion (95 per cent) were carried out in panama city. their purpose was to find out how useful this ulv technique could be in helping to combat mosquitoes, especially aedes aegypti. two residential areas were selected as sites for the trials. one of these was san francisco, a district near the shoreline of the bay of panama with many individual houses and a few tall buildings. the other was el cangrejo, a district further inland containing ...19751212538
virus-dependent mortality in rift valley fever, eastern equine encephalomyelitis, and chikungunya virus-inoculated mosquito (diptera: culicidae) larvae.the effect of inoculation of mosquito larvae with rift valley fever (rvf) virus on survival to the adult stage was evaluated in aedes aegypti (l.), ae. fowleri (charmoy), ae. mcintoshi huang, ae. taeniorhynchus (wiedemann), ae. triseriatus (say), eretmapodites quinquevittatus theobald, anopheles albimanus wiedemann, and culex pipiens l. pupation rates were similar for rvf virus-inoculated and diluent-inoculated larvae of all mosquito species tested except cx. pipiens. however, with the exception ...19921357176
tests for the existence of genetic determination or conditioning in host selection by anopheles albimanus (diptera: culicidae).the existence of sympatric populations within anopheles albimanus wiedemann with specific host preferences and the question of whether host selection has a genetic basis or is a learned characteristic were investigated. progeny of wild females collected from corrals or human bait were reared in an insectary. f1 females were fed on a cow or on a human host, allowed to oviposit, and then were released in an experimental hut divided into three compartments. the side rooms occupied by two human or o ...19921404273
field evaluation of an enzyme-linked immunosorbent assay for estimating the sporozoite rate in anopheles albimanus.we have verified for specimens of anopheles albimanus that an enzyme-linked immunosorbent assay (elisa) used to assess plasmodium vivax and p. falciparum sporozoite antigen rates gives results comparable to the salivary gland dissection method for estimating sporozoite rates. for 14,150 adults of an. albimanus, captured at five locations in guatemala, we report sporozoite antigen rates of 0.03-0.57%, which correlate with the malaria prevalences at the study sites. we also present data that sugge ...19921443346
gonotrophic cycle and survivorship of anopheles albimanus (diptera: culicidae) in southern mexico.the length of the gonotrophic cycle of anopheles albimanus was estimated by 12 mark-release-recapture studies conducted in corrals in southern mexico from 1987 to 1990. the initial set of three mark-release studies indicated that the gonotrophic cycle takes at least 4 d based on the day when gravid mosquitoes were first recaptured. however, in later experiments, mosquitoes recaptured seeking hosts at 48 h after release were in sella's and christophers' stages i and ii, but parity rates had nearl ...19921625288
efficacy assessment of quwenling, a mosquito repellent from china.quwenling, an insect repellent product of china derived from extracts of the lemon eucalyptus plant (eucalyptus maculata citriodon), was evaluated. laboratory tests compared quwenling with deet against anopheles albimanus, an. quadrimaculatus, aedes aegypti, ae. albopictus and field tests with ae. taeniorhynchus. cloth treated with quwenling at greater than 2x the dosage of deet was effective against 2 of 4 species tested (ae. albopictus 29 days, an. quadrimaculatus 28 days). on the skin of volu ...19911791453
genetic structure of natural populations of anopheles albimanus in colombia.electrophoretic and cytogenetic studies were undertaken on the population structure of anopheles albimanus from 11 localities in colombia, 3 from northern (atlantic coast) and 8 from southern (pacific coast) regions. of the 25 allozyme loci examined, significant allele frequency differences were observed at 4 loci: hydroxy acid dehydrogenase (had-1) and 3 esterases (est-2, est-4 and est-6). the northern populations had higher variability, with 55% polymorphic loci, a mean heterozygosity of 20.4% ...19911791454
field evaluation of ultra-low volume applications with a mixture of d-allethrin and d-phenothrin for control of anopheles albimanus in haiti.ultra-low volume applications of d-allethrin and d-phenothrin could possibly reduce populations of anopheles albimanus when used in conjunction with residual spraying of fenitrothion. the experiments were carried out in les cayes, haiti.19911791463
comparative sensitivity of four anopheles (diptera: culicidae) to five repellents.five repellents were evaluated against anopheles albimanus wiedemann an. freeborni aitken, an. gambiae giles, and an. stephensi liston, using a "free choice," dose-response testing procedure on rabbits. overall, deet was the most effective repellent based on effective dosages (ed50's and ed95's), except against an. albimanus. an. albimanus was significantly more tolerant to deet compared with dimethyl phthalate or ethyl hexanediol. permethrin was effective against all four anopheline species at ...19911875369
age structure and abundance levels in the entomological evaluation of an insecticide used in the control of anopheles albimanus in southern mexico.applications of bendiocarb produced a high insecticidal residual effect lasting up to 3 months on the most common indoor house surfaces. no significant decreases in mosquito man-biting rate levels were observed between treated and untreated villages. it was shown that almost equal proportions of intra- and peridomicillary mosquitoes came into contact with the insecticide, indicating that mosquitoes commonly enter houses, rest on treated surfaces and return to bite both indoors and outdoors. alth ...19911895076
plasmodium berghei ookinete densities in three anopheline species.plasmodium berghei ookinete kinetics and densities were examined in the blood meals of 3 species of anopheles mosquitoes fed simultaneously from a gametocytemic mouse. simple techniques were developed for estimating relative and absolute ookinete densities within individual mosquito blood meals. the kinetics of ookinete formation were similar in all 3 species, with peak ookinete densities occurring from 12 to 24 hr postingestion. ookinete densities consistently were lower in anopheles stephensi ...19911919925
structural diversity of trypsin from different mosquito species feeding on vertebrate blood.mosquito trypsin was purified using a combination of ion exchange and affinity chromatography with the ligand soybean trypsin inhibitor. three aedes and three anopheles species were tested, all of which are specialized in the digestion of vertebrate blood. amino-terminal sequences of hplc-purified trypsins from aedes aegypti and anopheles quadrimaculatus revealed homologies of 30-40% with vertebrate and other invertebrate proteases previously identified as serine-proteases. the purified mosquito ...19912065758
studies of the susceptibility of anopheles albimanus and anopheles vestitipennis from dajabon, dominican republic, to insecticides.insecticide susceptibility of anopheles albimanus and an. vestitipennis in dajabon province, dominican republic, was investigated. only 74.3% of an. albimanus exposed to 4% ddt for 1 h died. the mortality in this species following exposure for 1 h to 0.25% permethrin was also 74.3%. however, this species was susceptible to malathion, fenitrothion and propoxur. the mortality obtained following exposure of an. vestitipennis to 4% ddt and 0.1% propoxur, both for 1 h, was 71% and 100%, respectively. ...19902098471
bionomic studies of the anopheles mosquitoes of dajabon, dominican republic.field studies of dajabon province, dominican republic, revealed that anopheles albimanus and an. vestitipennis were the most abundant anopheline species followed by an. crucians and an. grabhamii. three of the species were collected as adults and larvae whereas an. grabhamii was found only in the adult stage. perennial ponds and rice fields were the most important larval habitats. the anophelines were predominantly exophilic and exophagic; however, outdoor resting sites could not be identified. ...19902098472
field evaluation of four biorational larvicide formulations against anopheles albimanus in honduras.four biorational larvicide formulations: teknar (b.t.i.), arosurf msf (monomolecular surface film), arosurf msf combined with teknar, and san-809-i ([s]-methoprene combined with b.t.i.), were evaluated against naturally occurring populations of the malaria vector mosquito anopheles albimanus wiedemann in honduras. all formulations reduced the mean number of larvae per sample area to 0 within 48 h after treatment, and gave significant (p less than 0.05) control when compared with similar untreate ...19902133006
[water pollution and presence of anopheles albimanus wiedemann, 1821 and culex nigripalpus theobald, 1901]. 19902259776
small scale field trials of bacillus sphaericus (strain 2362) against anopheline and culicine mosquito larvae in southern mexico.experimental breeding sites simulating natural conditions were used to evaluate the efficacy of 2 formulations of bacillus sphaericus (strain 2362) against anopheles albimanus and culicine (mostly culex coronator and cx. quinquefasciatus) mosquito larvae of southern mexico. three doses of each formulation were used in a first field trial: 2, 3 and 4 g/m2 (granular) or 2, 3 and 4 ml/m2 (liquid); and in a second field trial: 0.125, 0.24 and 0.5 g/m2 (granular) or 0.125, 0.25 and 0.5 ml/m2 (liquid) ...19902370538
variation in binding of bacillus sphaericus toxin and wheat germ agglutinin to larval midgut cells of six species of mosquitoes.bacillus sphaericus toxin labeled with fluorescein isothiocyanate was readily ingested by culex pipiens, aedes aegypti, anopheles stephensi, anopheles gambiae, anopheles quadrimaculatus, and anopheles albimanus larvae. fluorescent toxin bound to the luminal cell surface in discrete regions of the posterior midgut and gastric caecum in c. pipiens. in anopheles spp., toxin bound in a variable pattern to these structures and central and anterior midgut as well. the toxin did not bind to midgut cell ...19892566636
isolation and characterization of histones from anopheles albimanus weidemann.1. histones from anopheles albimanus adults were prepared by a combination of techniques including chromatin isolation and selective extractions. 2. the anopheline histones were identified on acid urea gels by comparing their electrophoretic profile with that of calf thymus histones and histones isolated from other tissue. 3. excellent separation of histones was obtained after the extractions by a single electrophoretic run. 4. in addition to the five major classes of histones found in eukaryote ...19892721151
factors influencing ingestion of particulate materials by mosquito larvae (diptera: culicidae).relative ingestion rates of mosquito larvae, as indicated by the number of substrate-filled gut segments per unit time, were determined for culex tarsalis coquillett, aedes aetypti l., and anopheles albimanus wiedemann. among the three species, ae. aegypti larvae were the most rapid feeders. f50 (median time for complete repletion of 50% of the larvae) was 61, 42, and 100 min for the three species feeding on a wheat flour suspension, respectively. food particles with nutritive values (dried yeas ...19892724318
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
microplate assay analysis of reduced fenitrothion susceptibility in haitian anopheles albimanus.reduced fenitrothion susceptibility in haitian anopheles albimanus is documented using time/mortality measurements from otherwise standard world health organization (who) bioassays. survival beyond a time threshold in bioassays is shown to be highly correlated with elevated non-specific esterase levels. a shift in resistance incidence from less than 20 to over 60% in a six-month period is documented using both the bioassay and microassay procedures, showing the potential of microplate assay meth ...19883193111
laboratory evaluation of formulations of bacillus thuringiensis var. israelensis combined with methoprene or a monomolecular surface film against anopheles albimanus and an. stephensi. 19883193121
microplate assay analysis of the distribution of organophosphate and carbamate resistance in guatemalan anopheles albimanus.simple microplate assay methods for determining the frequency of insecticide resistance in single mosquitos were used to study the distribution and localization of organophosphate and carbamate resistance in field populations of anopheles albimanus weidemann in guatemala, where such resistance, caused by heavy use of agricultural pesticides, has long been assumed to be widespread. areas of complete susceptibility to organophosphates and carbamates were observed, as well as areas where the resist ...19883262440
[susceptibility and/or resistance of adult anopheles albimanus wiedemann, 1821 (diptera: culicidae) to insecticides used in public health and in agriculture]. 19873313561
reduction of malaria prevalence after introduction of romanomermis culicivorax (mermithidae: nematoda) in larval anopheles habitats in colombia.the worldwide resurgence of malaria has become a major public health problem. new methods of controlling the vectors of the disease are required, and we therefore studied the biological control of anopheles albimanus by romanomermis culicivorax in colombia. the investigation was carried out in el valle and nuquí, two towns on the northern pacific coast of the country. all of the mosquito larval habitats surrounding el valle were seeded with the eggs and adults of r. culicivorax. the nematode est ...19873499249
efficacy of arosurf msf and formulations of bacillus thuringiensis var. israelensis against anopheles albimanus: laboratory bioassay.the efficacy of arosurf msf alone and in combination with three preparations of bacillus thuringiensis var. israelensis (b.t.i.) against anopheles albimanus larvae, pupae and eggs was determined by bioassay. arosurf msf alone was effective against the egg, 4th larval instar and pupal stages. all arosurf msf and b.t.i. combined formulations produced over 90% mortality of all larvae and pupae, 48 hr posttreatment. egg eclosion was reduced to approximately 25% with all formulations containing arosu ...19873504934
floating bait formulations increase effectiveness of bacillus thuringiensis var. israelensis against anopheles larvae.the development and screening of floating-type bait formulations designed to improve the activity of bacterial toxins against larval anopheles is described. floating and spreading abilities of carrier particles (wheat flour) were compared using corn oil, lecithin, and two products yielding surface films on water (arosurf and liparol). mixtures containing 1 or 5% arosurf showed the best spreading abilities on a water surface, but strongly inhibited the ingestion of wheat flour by anopheles albima ...19873504944
field trial in chiapas, mexico, of a rapid detection method for malaria in anopheline vectors with low infection rates.a method consisting of filtration of up to 100 macerated mosquitoes in a batch, followed by fixation with glutaraldehyde and concentration of filtrate by centrifugation has been developed to rapidly assess malaria infection in anopheline mosquitoes. determination of the presence of sporozoites is made by observation of a sample of the final filtrate with a phase microscope. the method is simple and field adaptable, essential factors for the application of any technique to large scale field opera ...19863513640
an evaluation of bendiocarb and deltametrin applications in the same mexican village and their impact on populations of anopheles albimanus. 19873664052
the sporogonic cycle of plasmodium reichenowi.plasmodium reichenowi, a malarial parasite of the chimpanzee, was infective to anopheles freeborni, anopheles quadrimaculatus, anopheles stephensi, anopheles maculatus, anopheles dirus, and anopheles culicifacies mosquitoes. anopheles gambiae and anopheles albimanus were not infected. mean oocyst diameters of p. reichenowi were smaller than those of the other chimpanzee parasite, plasmodium schwetzi. sporozoites were present in the salivary glands of an. freeborni at 15 days when held at 25 to 2 ...19863734994
maintenance of anopheles albimanus on frozen blood. 19853880275
infectivity of two strains of plasmodium vivax to anopheles albitarsis mosquitoes from colombia.anopheles albitarsis obtained from villavicencio, colombia, were colonized in the laboratory using force-mating techniques. laboratory reared mosquitoes were allowed to feed on aotus monkeys infected with the salvador ii or the rio meta strains of plasmodium vivax from el salvador and colombia, respectively. in comparison with other species, the an. albitarsis were less susceptible than anopheles freeborni, anopheles culicifacies and strains of anopheles albimanus from el salvador, panama and co ...19853912483
vector competence of cartagena strain of anopheles albimanus for plasmodium falciparum and p. vivax. 19853913070
evaluation of chlorphoxim used against anopheles albimanus on the south coast of mexico: 2. use of two curtain-trap techniques in a village-scale evaluation trial. 19854027455
studies on a newly isolated strain of plasmodium brasilianum in aotus and saimiri monkeys and different anophelines.a strain of plasmodium brasilianum was isolated from an aotus vociferans monkey from peru. the parasite readily infected aotus monkeys from bolivia and columbia and saimiri sciureus monkeys from peru and bolivia. highest level mosquito infections were obtained by feeding on the saimiri monkeys. the most susceptible mosquito was anopheles freeborni, followed by anopheles dirus, anopheles stephensi, anopheles gambiae, anopheles culicifacies, anopheles maculatus and anopheles albimanus. anopheles q ...19854093810
aliphatic amines against insecticide-susceptible and resistant strains of culex pipiens quinquefasciatus and anopheles albimanus. 19694387585
population patterns of anopheles albimanus and their significance to malaria abatement.data obtained between 1967 and 1972 on naturally occurring populations of a. albimanus in el salvador were used to construct 24-hour and seasonal patterns of activity for the species. the resulting patterns are discussed in terms of control implications, and specific examples are given to relate the importance of a knowledge of population dynamics to the success of conventional and alternative methods of anopheline control in malaria abatement programmes. a retrospective view of a successful fea ...19744548395
recent developments in methods of mosquito control.since residual insecticide spraying in domiciles does not sufficiently control some species of anophelines to halt malaria transmission, alternate methods of control have been investigated. these include ultra-low-volume (ulv) sprays or aerosols, the release of sterile males to suppress or eradicate populations, and the use of diseases or parasites to interfere with transmission or to reduce populations of mosquitos. the ulv aerial sprays gave practical control of anopheles albimanus in haiti an ...19744548396
release of chemosterilized males for the control of anopheles albimanus in el salvador. i. characteristics of the test site and the natural population. 19744817672
release of chemosterilized males for the control of anopheles albimanus in el salvador. ii. methods of rearing, sterilization, and distribution. 19744817673
release of chemosterilized males for the control of anopheles albimanus in el salvador. 3. field methods and population control. 19744817674
release of chemosterilized males for the control of anopheles albimanus in el salvador. iv. dynamics of the test population. 19744817675
selection for resistance to carbamate and organophoshorus insecticides in anopheles albimanus. 19714937399
plasmodium vivax transmitted from man to monkey to man.blood forms of human vivax malaria infected splenectomized night monkeys (aotus trivirgatus). anopheles albimanus mosquitoes transmitted the in fection from a monkey to two human volunteers; parasites and symptoms ap peared 11 days later. blood forms of vivax malaria from each of the two humans infected other night monkeys.19664958354
studies on resistance to carbamate and organophosphorus insecticides in anopheles albimanus. 19725074693
results of fenitrothion selection of culex pipiens fatigans wied. and anopheles albimanus wied.laboratory selection of culex pipiens fatigans (=c. quinquefasciatus) and anopheles albimanus by fenitrothion pressure for 30 and 25 generations, respectively, resulted in only 2.2-fold and 1.1-fold increases in tolerance to this compound. cross-resistance to arprocarb in culex increased 12.2-fold but smaller increases in tolerance to fenthion, malathion, ddt, and dieldrin, may be manifestations of vigour tolerance. since the essential conditions for selection are believed to have been fulfilled ...19695306322
ultrastructural study of early development of nosema algerae in anopheles albimanus. 19836411825
evaluation of chlorphoxim used against anopheles albimanus on the south coast of mexico: 1. results of indoor chlorphoxim applications and assessment of the methodology employed. 19846525482
progress in malaria vector control.malaria control, except in tropical africa, will probably continue to be based to a large extent on the use of insecticides for many years. however, the development of resistance to insecticides in the vectors has caused serious difficulties and it is necessary to change the strategy of insecticide use to maximize their efficacy. a thorough knowledge of the ecology and behaviour of each vector species is required before the control strategy can be adapted to different epidemiological situations. ...19816976842
studies on the west pakistan strain of plasmodium vivax in aotus monkeys and anopheline mosquitoes.the west pakistan strain of plasmodium vivax was established in 17 aotus trivirgatus griseimembra monkeys. parasitemias were moderate. prior experience of the animals with p. falciparum and a heterologous strain of p. vivax resulted in a marked reduction in parasitemias, but maintenance of mosquito infectivity similar to that of animals with no prior malaria. comparative infectivity studies indicated that this strain in aotus monkeys was most infective to anopheles freeborni mosquitoes followed ...19807007600
efficiency of techniques for the mass release of sterile male anopheles albimanus wiedemann in el salvador.during a 3-year program that required daily releases of large numbers of sterile male anopheles albimanus wiedemann mosquitoes in a coastal area of el salvador, we were able to compare methods of transport and release of adults and pupae. the disadvantages of the laboratory handling and packaging of adults were largely overcome when improved methods were devised for release of pupae. such releases saved time and laboratory space and overcame several logistical problems arising from evening relea ...19807406117
variation in ribosomal dna intergenic spacers among populations of anopheles albimanus in south and central america.variation in the length and copy number of intergenic spacers (igs) of nuclear ribosomal dna were examined to test for genetic differentiation among anopheles albimanus populations. extensive collections were made in guatemala but populations were also sampled over a large range of its distribution in central and south america. discriminant analysis of igs patterns in individual mosquitoes indicated that populations generally had unique sets of igs length variants. the igs patterns from populati ...19957485704
development of sporogonic cycle of plasmodium vivax in experimentally infected anopheles albimanus mosquitoes.the sporogonic cycle of plasmodium vivax was established and maintained under laboratory conditions in two different strains of anopheles albimanus mosquitoes using as a parasite source blood from human patients or from aotus monkeys infected with the vcc-2 p.vivax colombian isolate. both the tecojate strain isolate from guatemala and the cartagena strain from the colombian pacific coast were susceptible to infections with p.vivax. a higher percentage of cartagena mosquitoes was infected per tri ...19947565121
an immunological factor that affects anopheles gambiae survival.high titers of antibodies against anopheles gambiae midguts were produced in new zealand rabbits to identify midgut targets for an antimosquito vaccine. the serum from one of 8 rabbits (designated r2b6) killed 71.6% (abbott's adjusted % mortality) of an. gambiae within 7 days. mosquitoes ingesting r2b6 serum were unable to absorb their blood meal nutrients, resulting in reduced oviposition and egg hatching rates. anopheles stephensi and anopheles arabiensis were also killed when ingesting r2b6 s ...19957616189
effect of a cecropin-like synthetic peptide (shiva-3) on the sporogonic development of plasmodium berghei.the effect of a synthetic cecropin-like peptide, shiva-3, on in vitro ookinete development and on the early sporogonic stages of plasmodium berghei in the midgut of anopheles albimanus was investigated. peptide concentrations of 75 and 100 microm were effective (p < 0.05) in reducing ookinete production and the number of infected mosquitoes in almost all experiments. these peptide concentrations in the midgut were not toxic for the survival of the mosquitoes. complete inhibition was obtained if ...19957758540
knowledge, beliefs, and practices in relation to malaria transmission and vector control in guatemala.as part of an effort to involve community members in malaria control activities, we studied knowledge, beliefs, and practices of residents of both the pacific coastal plain and northeastern guatemala related to malaria transmission and anopheles albimanus control. most residents recognized the role of mosquitoes in malaria transmission, but few knew how mosquitoes acquired their infections or understood the risk of having an untreated person in their midst. if this were more widely known, reside ...19957771601
low-volume application by mist-blower compared with conventional compression sprayer treatment of houses with residual pyrethroid to control the malaria vector anopheles albimanus in mexico.village-scale trials were carried out in southern mexico to compare the efficacy of indoor-spraying of the pyrethroid insecticide lambda-cyhalothrin applied either as low-volume (lv) aqueous emulsion or as wettable-powder (wp) aqueous suspension for residual control of the principal coastal malaria vector anopheles albimanus. three indoor spray rounds were conducted at 3-month intervals using back-pack mist-blowers to apply lambda-cyhalothrin 12.5 mg a.i./m2 by lv, whereas the wp was applied by ...19957787228
influence of human breath on selection of biting sites by anopheles albimanus.the selection of biting sites by anopheles albimanus on a human host was studied in the laboratory. the perception of exhaled breath guided the mosquitoes towards the head region, and was associated with a preference (p < 0.001) for biting this part of the body. subsequent removal of breath resulted in a strong reduction of the number of bites on the head (from 49 to 20%). the significance of these findings in relation to host location is discussed.19947807088
salivary vasodilators of aedes triseriatus and anopheles gambiae (diptera: culicidae).salivary vasodilators of aedes aegypti (l.) and anopheles albimanus (wiedemann) were characterized previously as a tachykinin peptide and a catechol oxidase/peroxidase activity, respectively. to verify whether these two different vasodilators also were found in other distantly related members of each mosquito genus, we characterized the vasodilators from a. triseriatus and a. gambiae. a. triseriatus salivary gland homogenates produced a reversible, endothelium dependent vasorelaxation of rabbit ...19947966179
[the presence of mosquitoes (diptera: culicidae) and bioregulators in existing breeding grounds in areas served by a family physician in the municipality of fomento].research was made on the presence of mosquitoes (diptera: culicidae) in the fomento municipality health areas attended to by 52 family doctors, in sancti spíritus province. 19 species were found. culex quinquefasciatus and anopheles albimanus were the most widely found. fish and aquatic insect species serving as biological regulators were determined in each reservoir. the gambusia punctata was the larvivorous fish most frequently found and most widely disseminated. among predacious insects, thos ...19937984821
susceptibility of three laboratory strains of anopheles albimanus (diptera: culicidae) to coindigenous plasmodium vivax in southern mexico.three morphologically different pupal phenotypes (green, striped, brown) were selected from a parent strain of anopheles albimanus wiedemann collected from the suchiate region in the state of chiapas, mexico. significant differences in susceptibility to coindigenous plasmodium vivax grassi & feletti were observed when striped was compared with the parent colony as well as with brown and with green phenotypes. differences in susceptibility were not significant between the other phenotypes and the ...19948057314
salivary apyrase in african and new world vectors of plasmodium species and its relationship to malaria transmission.the salivary gland activities of apyrase, an enzyme that prevents platelet aggregation by eliminating adp, were compared among five members of the anopheles gambiae species complex and an. albimanus. within the an. gambiae group, an. quadriannulatus exhibited the lowest amount of enzyme activity at all ph levels measured. apyrase activity could be separated into three groups at ph 7.5 and 8.0. the two most anthropophilic species (an. gambiae and an. arabiensis) exhibited higher activity at ph 9. ...19948116818
preliminary observations on the changing roles of malaria vectors in southern belize.a survey for larval and adult anopheles mosquitoes was conducted in toledo district of southern belize during august-september 1992. we surveyed for larvae in 145 habitats and conducted paired indoor-outdoor collections of adult mosquitoes landing on humans at 6 houses. in 1940-41, kumm and ram reported anopheles darlingi females to be the most common anopheles mosquitoes inside houses and reported no specimens of anopheles vestitipennis in southern belize. in our 1992 survey we found no an. dar ...19938126482
plasmodium vivax sporozoite rates from anopheles albimanus in southern chiapas, mexico.anopheles albimanus mosquitoes were collected from august 1984 to november 1987 on intra- and peridomicile human bait in rancheria el gancho, chiapas, mexico. the mosquitoes were desiccated and stored in silicon chambers from 3 mo to 3 yr post-collection prior to being assayed using a direct enzyme-linked immunosorbent assay to detect plasmodium vivax predominant-type sporozoite protein. peridomicile-collected mosquitoes had a 10-fold higher sporozoite rate than those collected indoors, but only ...19948195955
effects of transmission-blocking immunity on plasmodium vivax infections in anopheles albimanus populations.two colonized populations of anopheles albimanus isolated from the suchiate region, chiapas state, mexico, were compared for their susceptibility to coindigenous plasmodium vivax. groups of mosquitoes were fed in vitro with either autologous donor blood or the same blood cells substituted with serum negative for anti-gametocyte antibody. significant differences in susceptibility between the 2 colonies were encountered if the autologous blood from a patient was fed to mosquitoes: mean infection r ...19948308663
cytostatic effect of lutzomyia longipalpis salivary gland homogenates on leishmania parasites.salivary gland homogenates (sgh) of female lutzomyia longipalpis, in concentrations as small as 0.05 pairs of glands/ml, inhibit the in vitro multiplication of promastigotes of leishmania mexicana amazonensis. the effect seems to be cytostatic since promastigote viability 24 hr after exposure ranged from 55% to 100% in different experiments. the cells cultivated in the presence of sgh were characterized by a very slender shape, with cell bodies that were almost two times as long as controls. the ...19938333578
indoor low-volume insecticide spray for the control of anopheles albimanus in southern mexico. village-scale trials of bendiocarb, deltamethrin and cyfluthrin.a comparative insecticide village-scale trial was carried out to determine the efficacy of low-volume (lv) indoor spray of bendiocarb, deltamethrin and cyfluthrin for the control of anopheles albimanus in a coastal plain of southern mexico. low-volume spray was conducted with knapsack mist-blowers, giving an average discharge rate of 215 ml/min, which deposited droplets of 50-100 microns. using this technique, 25 houses were treated/sprayman/day as compared with 8 houses/sprayman/day using conve ...19938350078
the salivary catechol oxidase/peroxidase activities of the mosquito anopheles albimanus.salivary gland homogenates from adult female anopheles albimanus mosquitoes relaxed aortic rings preconstricted with noradrenaline (na). this relaxation is slow and is due to destruction of na. incubation of na with the homogenate yielded a product with a spectrum consistent with the corresponding adrenochrome. oxidation of na was enhanced by a superoxide generation system and inhibited by the combined action of superoxide dismutase and catalase. additionally, peroxidase activity on both synthet ...19938393473
dynamics of population densities and vegetation associations of anopheles albimanus larvae in a coastal area of southern chiapas, mexico.spatial and seasonal variations on anopheles albimanus larval densities and their plant associations were investigated in larval habitats in southern mexico between april 1989 and may 1990. thirty-four plant groups were dominant in larval habitats. dense larval populations were associated with 3 genera of plants, cynodon, echinocloa and fimbristylis and no larvae were found in habitats with salvinia and rhizophora. low significant positive or negative associations were documented with the other ...19938468574
laboratory evaluation of repellents against four anopheline mosquitoes (diptera: culicidae) and two phlebotomine sand flies (diptera: psychodidae).deet, the lactone cic-4, and the piperidine compounds a13-37220 and a13-35765 were evaluated for initial repellency against laboratory-reared anopheles albimanus wiedemann, an. freeborni aitken, an. gambiae giles, an. stephensi liston, and phlebotomus papatasi (scopoli) using a dose-response testing procedure on human volunteers. in addition, deet and cic-4 were tested against lutzomyia longipalpis (lutz & neiva). in general, the repellency of a13-37220, a13-35765, and cic-4 was not markedly dif ...19938510108
noninfectious sporozoites in the salivary glands of a minimally susceptible anopheline mosquito.in studies to evaluate vector-malaria parasite relationships, we have found that anopheles albimanus is minimally susceptible to the rodent malaria parasite plasmodium yoelii. normally, less than 10% of a. albimanus develop oocyst infections compared to 80-100% for anopheles stephensi and anopheles freeborni mosquitoes. although sporozoites produced in a. albimanus invade the salivary glands, they are not infectious to balb/c or icr mice. in 11 experiments with sporozoites from a. albimanus, int ...19958544063
precise limitation of concerted evolution to orfs in mosquito hsp82 genes.two hsp82 genes were isolated from the malaria vector anopheles albimanus in a single lambda phage clone. the two genes are in a head-to-head arrangement separated by approx. 0.9 kbp. northern hybridizations and 5' race demonstrate that both genes are transcribed, have moderate levels of constitutive transcription, and are also heat-inducible with maximum transcript accumulation occurring after 40 degrees c heat shocks. both genes have typical heat-shock promoters and conserved intron boundaries ...19968630537
acquired transmission-blocking immunity to plasmodium vivax in a population of southern coastal mexico.naturally acquired transmission-blocking immunity to plasmodium vivax was studied in three groups of patients from the southern coast of mexico: primary cases (group a, 61% of the study population), secondary cases with the prior infection seven or more months earlier (group b, 23%), and secondary cases with the previous malaria experience within six months of the present study (group c, 16%). anopheles albimanus mosquitoes were fed with patients' infected blood cells in the presence of autologo ...19968644898
evaluation of controlled-release mosquito repellent formulations.eight polymer and 9 microcapsule formulations of deet were tested on laboratory rabbits against aedes aegypti and anopheles albimanus. several formulations were significantly more effective than simple (unformulated) deet at the same strength for periods up to 24 h. best results were obtained with a polymer formulation containing a high molecular weight fatty acid and 3 microcapsule formulations containing lanolin, gum arabic, gelatin, tannic acid, stearic acid, polypropylene glycol, water, and ...19968723256
proteolytic enzyme activity and plasmodium falciparum sporogonic development in three species of anopheles mosquitoes.if proteolytic enzymes affect the innate vector competence of anopheles mosquitoes for plasmodium infections, then mechanistic effects should be most pronounced at the zygote to ookinete developmental transition. anopheles freeborni, anopheles gambiae, and anopheles albimanus exhibit excellent, good, and poor susceptibility to p. falciparum, respectively. aminopeptidase and trypsin activity were determined relative to the kinetics of p. falciparum ookinete development in these 3 anopheles specie ...19968627478
nad(p)h-dependent production of oxygen reactive species by the salivary glands of the mosquito anopheles albimanus.salivary gland homogenates of the adult female mosquito anopheles albimanus, but not those of aedes aegypti, induced light production in the presence of nadph and luminol, indicating a nadph oxidase activity producing reactive oxygen species (superoxide anion) by the anopheline salivary homogenate. superoxide production by the anopheline salivary homogenate was also confirmed by the nadph-dependent, superoxide dismutase inhibitable, reduction of cytochrome c. the nadph oxidase reaction measured ...19968995793
behaviour of anopheles albimanus in relation to pyrethroid-treated bednets.responses of the malaria vector anopheles albimanus to pyrethroid impregnated bednets made of cotton or nylon, compared with untreated nets, were investigated in houses occupied by two people inside and/or outside two bednets, in coastal chiapas, méxico. the pyrethroid used was lambdacyhalothrin 30 mg a.i./m2. bioassay mortality rates of an.albimanus exposed to treated nets for 3 or 15 min, rose from 40-55% to 90-100% for nylon nets 3-19 weeks post-treatment, but were consistently lower for trea ...19979061682
assessment of a remote sensing-based model for predicting malaria transmission risk in villages of chiapas, mexico.a blind test of two remote sensing-based models for predicting adult populations of anopheles albimanus in villages, an indicator of malaria transmission risk, was conducted in southern chiapas, mexico. one model was developed using a discriminant analysis approach, while the other was based on regression analysis. the models were developed in 1992 for an area around tapachula, chiapas, using landsat thematic mapper (tm) satellite data and geographic information system functions. using two remot ...19979063370
reduction of mosquito larval densities in natural sites after introduction of romanomermis culicivorax (nematoda:mermithidae) in cuba.romanomermis culicivorax ross & smith became established in 4 of 6 treated sites and produced high levels of infection in anopheles albimanus wiedemann, culex atratus theobald, psorophora confinnis lynch-arribálzaga, and uranotaenia sapphirina oster-sacken mosquitoes for 9 wk in 1993. mean levels of southern house mosquito parasitism ranged from 82 to 83% for culex quinquefasciatus say, at 2 sites, from 89 to 95% for an. albimanus at 4 sites, and from 78 to 80% at 2 sites for cx. atratus, ps. co ...19979086702
regular production of infective sporozoites of plasmodium falciparum and p. vivax in laboratory-bred anopheles albimanus.one of the major constraints for studies on the sporogonic cycle of the parasites causing human malaria, and on the protective efficacy of pre-erythrocytic vaccines, is the scarcity of laboratory-reared anopheles mosquitoes as a source of infective sporozoites. the aim of the present study was to reproduce the life-cycles of plasmodium falciparum and p. vivax in the laboratory and so develop the ability to produce infective sporozoites of these two species regularly under laboratory conditions. ...19979093429
use of generalized regression tree models to characterize vegetation favoring anopheles albimanus breeding.we propose the use of generalized tree models (gtms) to analyze data from entomological field studies. generalized tree models can be used to characterize environments with different mosquito breeding capacity. a gtm simultaneously analyzes a set of predictor variables (e.g., vegetation coverage) in relation to a response variable (e.g., counts of anopheles albimanus larvae), and how it varies with respect to a set of criterion variables (e.g., presence of predators). the algorithm produces a tr ...19979152872
anopheles albimanus (diptera: culicidae) host selection patterns in three ecological areas of the coastal plains of chiapas, southern mexico.the host-feeding patterns of anopheles albimanus wiedemann were described and the effect of host availability on these patterns was assessed in three different ecological areas of coastal chiapas, mexico. resting mosquitoes were collected indoors and outdoors during rainy seasons. a 20% sample of blood-fed mosquitoes was tested to determine the source of the blood meal using an elisa. the unweighted human blood index (hbi) of an. albimanus in the three areas ranged from 0.11 to 0.21. this mosqui ...19938510111
mixed-species plasmodium infections of anopheles (diptera:culicidae)mixed-pathogen infections of vectors rarely are considered in the epidemiological literature, although they may occur in nature. a review of published reports shows that many anopheles species are capable of carrying sporozoites of > 1 plasmodium species, of doing so simultaneously in field conditions, and of acquiring and transmitting these in experimental situations. mixed-species infections in mosquito populations occur at frequencies greater than or equal to the product of the constituent sp ...19979220675
characterization and biological activity of a brazilian isolate of bacillus sphaericus (neide) highly toxic to mosquito larvae.primary powders of bacillus sphaericus strain s2 isolated from soil samples in brazil, and strain 2362 were produced in a 14 liter fermentor. growth patterns and sporulation observed in three trials with strains s2 and 2362 in the fermentor were similar. second-instar larvae of culex quinquefasciatus, anopheles albimanus, anopheles quadrimaculatus, and aedes aegypti exposed for 48 hr to strain s2 responded with lc50 values of 0.25, 5.95, 12.28 and 140.0 ppb of lyophilized primary powder, respect ...19969283664
diel oviposition periodicity of anopheline mosquitoes (diptera: culicidae) from the americas: anopheles albimanus wieldemann and anopheles freeborni aitken.the diel oviposition patterns of anopheles albimanus and an. freeborni derived from panama and california, u.s.a., respectively, were studied in the laboratory by recording the egg-laying of individuals and colonies at 2-h intervals. anopheles freeborni oviposition patterns were almost exclusively nocturnal, with 80% of eggs being laid during the scotophase. a large, well-defined peak of oviposition, comprising about 70% of eggs laid, occurred 4-6 h before sunrise. anopheles albimanus ovipositio ...19938311576
multiple blood meals as a reproductive strategy in anopheles (diptera: culicidae)multiple blood meals within one gonotrophic cycle were taken readily at 6-24-hr intervals by nulliparous female anopheles albimanus wiedemann. up to five blood meals were ingested and with each blood meal, more primary follicles matured as well as some secondary ones. this produced an irregular oviposition pattern that questioned the concept of gonotrophic concordance. the first blood meal initiated limited vitellogenesis and the maturation of few follicles. instead, protein was diverted to the ...19938271256
chymotrypsin inhibitors in mosquitoes: activity profile during development and after blood feeding.chymotrypsin and trypsin inhibitors persist throughout all developmental instars of aedes aegypti. after a blood meal, inhibitor activity against chymotrypsin was more than double that of sugar-fed females, but only weak activity was detected in midguts where proteinase inhibitors has been thought to regulate proteinases during blood digestion. a fourfold increase in the ratio of abdominal/thoracic inhibitor activity after the blood meal strongly suggested that fat body, or other abdominal tissu ...19979366013
a comparison of two collection methods for estimating abundance and parity of anopheles albimanus in breeding sites and villages of southern mexico.the abundance and age structure of anopheles albimanus populations were estimated by uv updraft light traps and human landing catches within villages and in nearby breeding sites of southern méxico. four villages and 5 breeding sites were selected for the study. light trap and human landing catches were simultaneously carried out in each breeding site and each village. anopheles albimanus was the most abundant malaria vector caught in breeding sites and in villages. significant differences in ov ...19979383764
laboratory bioassay to compare susceptibilities of aedes aegypti and anopheles albimanus to bacillus thuringiensis var. israelensis as affected by their feeding rates.this study presents the effect of differences in the feeding rates of aedes aegypti and anopheles albimanus on their susceptibilities to bacillus thuringiensis israelensis. aedes aegypti was more susceptible than an. albimanus because of its faster rate of feeding. aedes aegypti ingested 11.5 times more spores than did an. albimanus, resulting in lower lt50 values. anopheles albimanus larvae fed at a slower rate and required fewer spores than ae. aegypti to induce 50% mortality. these findings s ...19989599326
immunogenicity of four plasmodium falciparum preerythrocytic antigens in aotus lemurinus monkeys.aotus lemurinus monkeys were immunized with pools of either lipid-tailed peptides injected in pbs or peptides in montanide isa-51, all derived from four plasmodium falciparum pre-erythrocytic antigens, namely, lsa1, lsa3, salsa, and starp. these formulations were well tolerated. their immunogenicity was demonstrated by the induction of both b- and t-cell responses to most of the peptides studied (of the 12, 10 induced antibody production, 9 induced t-cell proliferative responses, and all 12 indu ...19989632616
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