| genetic study of the susceptibility of anopheles gambiae to infection with malaria parasites. | | 1993 | 8233605 |
| dna probes for the identification of malaria vectors. | the correct identification of the mosquito vectors of malaria is essential to determine the vectorial significance of the different species within species complexes and to optimise vector control programmes. a number of methods are available including cytogenetic analysis, isoenzyme characterisation, and mating incompatibility. we describe here the development of a simplified dna probe methodology for the identification of malaria vector specimens, with particular emphasis on the identification ... | 1993 | 8233607 |
| the ecology and behaviour of the forest form of anopheles gambiae s.s. | studies on the ecology of anopheles gambiae s.s. and the transmission of malaria were undertaken in a high rainfall forested area in southern sierra leone. anopheles gambiae s.s., identified by chromosomal techniques as the forest form, was the only malaria vector in the study village. surprisingly, rice fields or swamps were not favoured breeding places for this species; breeding mainly occurred in temporary pools. the mean annual sporozoite rate of an. gambiae s.s. determined by elisa was 3.9% ... | 1993 | 8233612 |
| malaria transmission-blocking activity in the plasma of plasmodium falciparum gametocyte carriers in cameroon. | experimental infections of anopheles gambiae were carried out with plasmodium falciparum gametocytes from 65 naturally infected patients in cameroon. a comparison was made between infections with blood containing autologous plasma and blood in which the plasma was replaced by plasma from donors without previous malaria exposure. a lower mosquito-infection rate was observed in 50 out of 65 autologous plasma samples. the transmission was completely blocked in 8 infections, whilst belonging exposur ... | 1993 | 8233616 |
| temporal and spatial expression of serine protease genes in anopheles gambiae. | serine proteases play a crucial role during the digestion of the blood meal in the mosquito gut. the isolation and the analysis of the genomic organisation of the corresponding genes may lead to the characterization of gut-specific, inducible promoters, suitable for the expression of anti-parasitic agents in the gut of transgenic mosquitoes. we report here on the identification of a trypsin and a chymotrypsin gene family of anopheles gambiae. following a blood meal, the transcription of all memb ... | 1993 | 8233618 |
| polytene chromosome microdissection and molecular genome mapping in drosophila and other dipterans. | we are constructing a molecular physical map of the drosophila melanogaster genome, using microdissection of polytene chromosomes as a source of region specific probes applied to direct mapping work. chromosome microdissection has been used for a low resolution map of the anopheles gambiae s.s. genome. | 1993 | 8233623 |
| evaluation of light traps for sampling anopheline mosquitoes in kilifi, kenya. | anopheline mosquitoes were sampled inside houses, where residents slept under untreated bednets, by cdc light traps and human-biting catches to evaluate light traps as a means for determining human exposure to malaria vectors in kilifi district, kenya. mosquitoes were sampled during 2 all-night collections by light traps and one all-night biting catch in a series of 262 houses. collections yielded 1,721 anopheles gambiae s.l. and 46 an. funestus, and 60.3% of the houses were negative for anophel ... | 1993 | 8245934 |
| laboratory evaluation of the irritancy of bendiocarb, lambda-cyhalothrin and ddt to anopheles gambiae. | in a laboratory study, the irritancy of bendiocarb, lambda-cyhalothrin and ddt to anopheles gambiae was evaluated at field, 1/3 field and 1/10 field rates using who conical exposure chambers and excito-repellency test boxes. bendiocarb was the least irritant insecticide at all rates, inducing levels of takeoff, flight and exiting behavior similar to those of a distilled water control treatment. of those mosquitoes introduced to the bendiocarb-treated boxes, not more than 1% exited and survived a ... | 1993 | 8245937 |
| immunological localization of bacillus thuringiensis serovar israelensis toxins in midgut cells of intoxicated anopheles gambiae larvae (diptera: culicidae). | fourth instar larvae of anopheles gambiae were intoxicated with doses of purified crystals from bacillus thuringiensis serovar israelensis (bti) corresponding to 50-fold the lc50 after 24 h. midguts were dissected after various contact times, then processed for immuno-light and -electron microscopy. immunodetection on thin sections was performed using affinity-purified rabbit igg against bti crystal cryivd or cyta polypeptides, in combination with anti-rabbit igg/peroxidase. both polypeptides we ... | 1993 | 8248622 |
| importance of low dispersion of anopheles gambiae (diptera: culicidae) on malaria transmission in hilly towns in south cameroon. | the dispersion of anopheles gambiae giles s.l. from larval breeding places was examined in the towns of yaounde and edea, cameroon. the study areas are characterized by hilly reliefs of approximately 40 m and by larval breeding places in the swampy valleys. mosquito density was estimated by night-biting indoor catches carried out during 1 yr in three districts, with four collecting houses in each, along a transect from 0 (at the valley bottom) to 350 m (at the hilltop). in each district, the hum ... | 1993 | 8254644 |
| evaluation of the polymerase chain reaction method for identifying members of the anopheles gambiae (diptera: culicidae) complex in southern africa. | chromosomally and electrophoretically identified field samples of members of the anopheles gambiae giles complex from southern africa and colony material were used to test the polymerase chain reaction (pcr) method of identification. the samples included an. arabiensis patton, an. quadriannulatus theobald, and an. merus donitz. only one of the 217 specimens examined was disputed. twenty specimens (9%) were reamplified because of the presence of multiple bands or lack of amplification after the f ... | 1993 | 8254648 |
| visual assessment of sporozoite elisa results is as reliable as a plate reader in determining infection rates in field samples of anopheles gambiae s.s. | | 1993 | 8266421 |
| effects of adult body size on fecundity and the pre-gravid rate of anopheles gambiae females in tanzania. | the influence of adult body size on the pre-gravid state and fecundity was studied in anopheles gambiae giles females hand-caught inside houses and virgin females collected as pupae in tanzania. blood-fed mosquitoes were kept for 2-3 days before dissection and examination for insemination and ovarian condition. those females which did not develop eggs were classified as pre-gravid. the number of mature eggs in those mosquitoes which became gravid was counted. virgin females were fed and kept for ... | 1993 | 8268486 |
| confirmation that plasmodium falciparum has aperiodic infectivity to anopheles gambiae. | in preparation for field studies of transmission-blocking malaria vaccines, a study was carried out to determine whether p. falciparum infections obtained in an. gambiae blood-fed at 16.00 hours were quantitatively similar to infections obtained at 23.00 hours. using a group of children aged 5-12 years from villages at ahero, near kisumu in kenya, 71/74 (96%) of whom were found to be positive for p.falciparum parasitaemia, one batch of fifty colony-bred an.gambiae females were fed on volunteers ... | 1993 | 8268494 |
| codon usage patterns in chromosomal and retrotransposon genes of the mosquito anopheles gambiae. | codon usage was compiled for fourteen chromosomal genes and four retrotransposons from the mosquito anopheles gambiae. variation exists among chromosomal genes in the degree of bias. the genes showing the highest bias are probably most highly expressed. in these genes, the base composition at the third codon position is much richer in g + c than is the overall coding sequence. thus, codon usage is biased toward g- or c-ending codons. codon usage in each retrotransposon is quite different, not on ... | 1993 | 8269095 |
| random amplified polymorphic dna (rapd) markers readily distinguish cryptic mosquito species (diptera: culicidae: anopheles). | the usefulness of random amplified polymorphic dna (rapd) was examined as a potential tool to differentiate cryptic mosquito species. it proved to be a quick, effective means of finding genetic markers to separate two laboratory populations of morphologically indistinguishable african malaria vectors, anopheles gambiae and an. arabiensis. in an initial screening of fifty-seven rapd primers, 377 bands were produced, 295 of which differed between the two species. based on criteria of interpretabil ... | 1993 | 8269099 |
| 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 ... | 1993 | 8271256 |
| salivary gland surface carbohydrate variations in three species of the anopheles gambiae complex. | fluorescein isothiocyanate (fitc)-conjugated lectins (agglutinins) were employed as probes to distinguish between the various carbohydrates present on the surface of salivary glands of three species of mosquito of the anopheles gambiae complex. of twenty lectins tested, eight (concanavalin a- con a, lathyrus odoratus- loa, lens culinaris, pisum sativum-psa, vicia faba- vfa, triticum vulgaris, maclura pomifera- mpa and ulex europaeus) specifically reacted with the salivary gland membrane. both ma ... | 1993 | 8279867 |
| [malaria indices, larval ecology and trophic activity of anopheles mosquitoes in djohong (adamaoua, cameroon) in the rainy season]. | in djohong in the wet season the prevalence of malaria is 17.5% for plasmodium falciparum and 1.1% for plasmodium malariae. in children 2 to 9 years of age the plasmodic index is 38.6% (mesoendemicity) for the children of the peasants and 9.4% for those belonging to other socioeconomical groups. in infants less than 12 months old, the plasmodic index is 9.3%, this relatively high rate corresponding to the high transmission period of the rainy season. anopheles gambiae is the mosquito species mos ... | 1993 | 8289630 |
| entomological risk factors for severe malaria in a peri-urban area of the gambia. | a study was undertaken of possible entomological risk factors for severe malaria in a peri-urban area of the gambia. households of children who had experienced a severe or a mild attack of malaria and of matched controls were visited and their characteristics recorded. mosquitoes were then collected in the bedrooms of study subjects using both insecticide spray catches and light traps. mud-walled buildings and bedrooms without ceilings were found more frequently in the households of children who ... | 1993 | 8311575 |
| [mosquito nets impregnated against malaria in zaire]. | on the bateké plateau 60 km east of kinshasa, zaïre, where malaria is stable, three villages have been selected for a trial of malaria control using bednets impregnated with deltamethrin at 25 mg per square meter from february to november 1991. one village (3,000 inhabitants) has been provided 800 impregnated bednets and an other one (2,900 inhabitants) kept 800 non impregnated bednets. the third village (900 inhabitants) served as a control and has remained without nets. anopheles gambiae was t ... | 1993 | 8323407 |
| members of a trypsin gene family in anopheles gambiae are induced in the gut by blood meal. | serine proteases are among the enzymes that play a crucial role during the digestion of the blood meal in the gut of mosquitoes. the identification of the corresponding genes would have important implications for the control of mosquitoes and mosquito-borne diseases. analysis of the genomic organization of these genes may lead to the isolation of a gut-specific, inducible promoter for the expression of anti-parasitic agents in transgenic mosquitoes. moreover, specific inhibitors could be designe ... | 1993 | 8335004 |
| a detailed genetic map for the x chromosome of the malaria vector, anopheles gambiae. | anopheles gambiae, the primary vector of human malaria in africa, is responsible for approximately a million deaths per year, mostly of children. despite its significance in disease transmission, this mosquito has not been studied extensively by genetic or molecular techniques. to facilitate studies on this vector, a genetic map has been developed that covers the x chromosome at an average resolution of 2 centimorgans. this map has been integrated with the chromosome banding pattern and used to ... | 1993 | 8342025 |
| bloodfeeding behavior of anopheles gambiae s.l. and anopheles funestus in kilifi district, kenya. | blood meal samples were tested by elisa for 534 anopheles gambiae s.l. and 76 anopheles funestus collected from 25 sites in kilifi district, kenya. human igg was detected in 94.4% of the an. gambiae s.l. and in 90.8% of the an. funestus. no samples were positive for cow and only a few were positive for goat. both species fed predominantly on humans irrespective of host availability. at these sites on the kenyan coast, the high degree of human-feeding by malaria vectors contributes to the efficie ... | 1993 | 8350080 |
| low-level plasmodium falciparum transmission and the incidence of severe malaria infections on the kenyan coast. | the transmission of plasmodium falciparum was studied in relation to the incidence of severe malaria infections at sokoke and kilifi town, kilifi district, kenya. intensive mosquito sampling during a one-year period yielded anopheles gambiae s.l., an. funestus, and an. coustani. anopheles gambiae s.l. was the predominant vector, comprising 87.9% and 97.9% of the total anophelines collected in sokoke and kilifi town, respectively. the proportion of an. gambiae s.l. with p. falciparum sporozoite i ... | 1993 | 8357087 |
| analysis of mosquito bloodmeals by dna profiling. | human specific genetic markers have been used to profile the human dna found within a mosquito bloodmeal. in this technique, variable numbers of tandem repeat (vntr) sequences are employed to prime amplification of human dna in the polymerase chain reaction (pcr) and the radiolabelled products are analysed by high resolution denaturing gel electrophoresis. matching of dna profiles allows identification of the individual human host. bloodmeals of 125 female anopheles gambiae giles mosquitoes, cau ... | 1993 | 8369554 |
| sequence of a cdna from the mosquito anopheles gambiae encoding a homologue of human ribosomal protein s7. | | 1993 | 8371989 |
| association of two esterase genes, a chromosomal inversion, and susceptibility to plasmodium cynomolgi in the african malaria vector anopheles gambiae. | the ability of a selected strain of the malaria vector anopheles gambiae to encapsulate the early oocysts of the malaria parasite plasmodium cynomolgi b has previously been shown to be genetically linked to specific esterase phenotypes. this association between plasmodium susceptibility and esterase phenotype is found in the an. gambiae g3 strain from which the plasmodium-refractory and -susceptible mosquito strains were derived. genetic crosses had suggested that the esterase phenotypes reflect ... | 1993 | 8372956 |
| the mariner transposable element is widespread in insects. | the mariner transposable element is a small member of the short inverted terminal repeat class thought to transpose through a dna intermediate. originally described in drosophila mauritiana, it is now known in several species of the family drosophilidae, and in a moth hyalophora cecropia. here i use primers designed to represent regions of amino-acid conservation between the putative transposase genes of the d. mauritiana and h. cecropia elements to amplify equivalent regions of presumed mariner ... | 1993 | 8384700 |
| prospects for the use of larvivorous fish for malaria control in ethiopia: search for indigenous species and evaluation of their feeding capacity for mosquito larvae. | because of problems with drug and insecticide resistance, the national organization for the control of malaria and other vectorborne diseases, ethiopia, has embarked on a programme of research on alternative malaria control methods, including the use of biological control agents, such as larvivorous fish. the objectives of the study were to identify indigenous larvivorous fish species which could be potential candidates for use as biological control agents; to extend knowledge of their distribut ... | 1993 | 8429570 |
| enzyme variation at the aspartate aminotransferase locus in members of the anopheles gambiae complex (diptera: culicidae). | the enzyme aspartate aminotransferase (aat) currently is used to identify anopheles quadriannulatus theobald, the animal-biting, nonmalaria vector species of the anopheles gambiae complex. samples of an. quadriannulatus from south africa and an. gambiae giles s.str. from the island of grand comoros and the people's republic of congo have shown variation in electromorph frequencies that indicate that aat has five alleles. the three slowest alleles are found in an. quadriannulatus and the three fa ... | 1993 | 8459407 |
| variation in attractiveness of human subjects to malaria mosquitoes (diptera: culicidae) in the gambia. | during experimental hut trials to assess the efficacy of insecticide-treated bednets against malaria mosquitoes, we observed that human subjects varied consistently in their attractiveness to mosquitoes. attractiveness was assessed by estimating the numbers of wild anopheles gambiae giles mosquitoes entering a hut in which a man was sleeping, and the numbers of human-bloodfed an. gambiae sensu lato collected from each hut each morning. five trials were carried out at wali kunda in rural gambia d ... | 1993 | 8459413 |
| experimental infection of anopheles gambiae s.s., anopheles freeborni and anopheles stephensi with plasmodium malariae and plasmodium brasilianum. | susceptibility to infection of 2 strains of anopheles gambiae s.s., an. freeborni and an. stephensi, was determined for 2 closely related malaria parasites, plasmodium malariae and p. brasilianum. neither strain of an. gambiae supported development of oocyst densities as great as the other 2 anopheline mosquitoes. the zan strain of an. gambiae s.s. from zanzibar was more susceptible to infection with the strain of p. malariae from uganda than the g-3 strain of an. gambiae s.s. from the gambia. a ... | 1993 | 8468576 |
| laboratory colonization of anopheles quadriannulatus from sympatry with other sibling species of the anopheles gambiae complex in zimbabwe. | a laboratory colony of the mosquito anopheles quadriannulatus was established from a wild population occurring sympatrically with an.arabiensis in zimbabwe. these sibling species are members of the an.gambiae giles complex and were distinguished primarily by means of their specific polytene chromosome banding patterns. by using an ox-baited trap, we sampled selectively for the more zoophilic an.quadriannulatus. it was confirmed that an.quadriannulatus has the diagnostic slow allozyme of aspartat ... | 1993 | 8481528 |
| malaria in urban and rural kinshasa: the entomological input. | mosquitoes were collected on human bait over a 16-month period (september 1988 to december 1989) in an urban and a rural area of kinshasa, zaïre. p. falciparum malaria sporozoite rates were determined by elisa. in the urban area culex quinquefasciatus accounts for 96% of the 121 bites/person/night (b/p/n). the only anopheline is anopheles gambiae, sensu stricto, with an average of 5.1 b/p/n and a sporozoite rate of 1.86%. the entomological inoculation rate (eir) averages 0.08 infective b/p/n. ma ... | 1993 | 8481529 |
| deforestation: effects on vector-borne disease. | this review addresses changes in the ecology of vectors and epidemiology of vector-borne diseases which result from deforestation. selected examples are considered from viral and parasitic infections (arboviruses, malaria, the leishmaniases, filariases, chagas disease and schistosomiasis) where disease patterns have been directly or indirectly influenced by loss of natural tropical forests. a wide range of activities have resulted in deforestation. these include colonisation and settlement, tran ... | 1993 | 8488073 |
| [the culicidian fauna and its nuisance in kinshasha (zaire)]. | a public health study to inventory bloodsucking mosquitoes was conducted in kinshasa and its regions. 20 culicidian species were represented by 7 anopheles, 6 culex, 5 aedes and 2 mansonia. in general, the number of bites/man/night (b/m/n) was in average 141.5 of cx. quinquefasciatus, 60.1 of cx. antennatus, 21.1 of m. africana, 16.3 of an. gambiae and 7.7 of m. uniformis. the nuisance is different from region to other. culex quinquefasciatus is the most abundant and aggressive species in the ur ... | 1993 | 8504267 |
| baseline entomological data for a pilot malaria control program in equatorial guinea. | entomological studies conducted on the island of bioko and the mainland province, río muni, in equatorial guinea provided baseline data for a pilot malaria control program. the main species collected resting in houses at low density were anopheles gambiae s.l. giles and anopheles funestus giles. an. gambiae s.l. density increased during the rainy season, whereas an. funestus populations remained stable during both dry and wet seasons. both species tended to be endophilic and were not collected r ... | 1993 | 8510123 |
| high human malarial infectivity to laboratory-bred anopheles gambiae in a village in burkina faso. | the malarial infectivity of an african village population was tested by selecting a demographically representative sample of individuals for study, regardless of parasitemia or gametocytemia. the infectivity of this population people to laboratory-bred mosquitoes was investigated using membrane feeding techniques. tests on 322 subjects (greater than four years of age) indicated that approximately 48.4% were capable of infecting mosquitoes. there were similar proportions of infectious individuals ... | 1993 | 8517489 |
| malaria epidemiology in the province of moyen ogoov, gabon. | in the course of epidemiological and immunological baseline studies parasitological surveys were conducted, in 1992, in three localities situated in our near rain forest in the area of lambaréné, gabon, western central africa. anopheles gambiae s.s. and a. funestus are considered to be the main vectors of malaria. the three localities represent strata with obvious differences in the intensity of malaria transmission. the lowest parasite rates were recorded in the village around the albert-schwei ... | 1995 | 8525289 |
| vectorial capacity and entomological inoculation rates of anopheles gambiae in a high rainfall forested area of southern sierra leone. | we report the first study of gonotrophic cycle duration, survival rates, pre-gravid rates, vectorial capacity and chromosomal polymorphism of anopheles gambiae s.s. in sierra leone. in the village of bayama in the southern province, an. gambiae was the only species found to be naturally infected with plasmodium falciparum and it constituted 99.7% of 22,541 anopheline mosquitoes caught. chromosomal studies revealed only an. gambiae s.s. out of 66 females examined for chromosomal polymorphism, 61 ... | 1995 | 8533019 |
| olfactory responses of host-seeking anopheles gambiae s.s. giles (diptera: culicidae). | | 1995 | 8533668 |
| movement of anopheles gambiae s.l. malaria vectors between villages in the gambia. | movement of mosquitoes belonging to the anopheles gambiae complex (mixed wild populations of an.arabiensis, an.gambiae and an.melas) between three neighbouring rural villages in the gambia was investigated by mark-release-recapture. a total of 12,872 mosquitoes were collected in bednets, marked with a magenta fluorescent powder and released over a 15-day period in one of the villages. a further 15,507 mosquitoes were collected in exit traps, marked with a yellow powder and released over the same ... | 1995 | 8541594 |
| detection of plasmodium sporozoites in mosquitoes by polymerase chain reaction and oligonucleotide rdna probe, without dissection of the salivary glands. | dried anopheles gambiae mosquito head+thorax portions, infected with plasmodium falciparum sporozoites, were processed by the polymerase chain reaction. the pcr product was hybridized to an oligonucleotide probe (known as 114r or aw34) diagnostic for plasmodium. the detection level by autoradiography was ten sporozoites per mosquito. head+thorax of mosquitoes that contained mature p.falciparum oocysts, without sporozoites, gave no positive signal, indicating that the test detects only infective ... | 1995 | 8541598 |
| towards malaria control in nigeria: a qualitative study on the population of mosquitoes. | malaria is still highly prevalent in many tropical countries and this disease can only survive in areas where mosquitoes and infected human populations are high. relevant information on the species of mosquitoes, their habitats and their population are important in planning preventative strategies in the control of malaria, hence this study. mosquito species and their habitats were investigated in both high and low density areas of benin city, edo state, nigeria. the results showed that culex pi ... | 1995 | 8568784 |
| the sequence, organization, and evolution of the locusta migratoria mitochondrial genome. | the sequencing of the cloned locusta migratoria mitochondrial genome has been completed. the sequence is 15,722 bp in length and contains 75.3% a+t, the lowest value in any of the five insect mitochondrial sequences so far determined. the protein coding genes have a similar a+t content (74.1%) but are distinguished by a high cytosine content at the third codon position. the gene content and organization are the same as in drosophila yakuba except for a rearrangement of the two trna genes trnalys ... | 1995 | 8587138 |
| the effect of permethrin-impregnated wall-curtains on malaria transmission and morbidity in the suburbs of maputo, mozambique. | the effect of nylon-netting wall-curtains impregnated with 0.5 g permethrin/m2 upon the biting rate of malaria vectors (anopheles gambiae s.l. and an. funestus) and on the plasmodium falciparum parasite rate, and morbidity due to malaria in children under five and between five and fourteen years was tested in the maputo area. the curtains significantly lowered biting rates of both vector species inside curtained houses, but reduced inside resting and outside biting only in an. funestus. the perc ... | 1995 | 8592765 |
| differential attractiveness of isolated humans to mosquitoes in tanzania. | individually occupied tents, modified for sampling mosquitoes, were used to assess the attractiveness of 3 humans for anopheles gambiae giles s.l., a. funestus giles, culex quinquefasciatus say and mansonia spp. in north-east tanzania. significant differences (p < 0.025) in attractiveness were observed for the first 3 species, whereas mansonia did not show any preference. because of the objective sampling method used, these results provide the first conclusive evidence that isolated people vary ... | 1995 | 8594668 |
| conserved function of anopheles gambiae midgut-specific promoters in the fruitfly. | control of malaria by a methodology that would permit the effective blockage of the anopheles gambiae midgut wall penetration by plasmodium parasites requires a detailed understanding of both the physiology of the mosquito's digestion, and of the interactions between the parasite and its host. we have transformed drosophila melanogaster with several constructs that allow the study of the promoter region of two of the major late trypsin genes of a. gambiae. using several deletions, we have identi ... | 1996 | 8617209 |
| effect of the sickle cell trait status of gametocyte carriers of plasmodium falciparum on infectivity to anophelines. | insect-reared anopheles gambiae were experimentally fed with the blood of naturally infected human volunteers carrying gametocytes of plasmodium falciparum. infection of at least one mosquito was successful in 86 experiments. for these gametocyte carriers, the hemoglobin types studied were aa (normal, n = 77), as (heterozygous sickle cell, n = 8), and ss (homozygous sickle cell, n = 1). the mean of the percentages of infected mosquitoes by gametocyte carriers of as hemoglobin was almost double t ... | 1996 | 8619431 |
| possible contributing factors to the paucity of yellow fever epidemics in the ashanti region of ghana, west africa. | yellow fever virus vectors identified in the ashanti region of ghana included aedes aegypti, aedes africanus, aedes luteocephalus and aedes vittatus. other mosquito species, unrelated to yellow fever transmission, identified in this study included culex tigripes, culex thalassius, culex decens, culex tarsalis, anopheles gambiae, anopheles stephansi and toxorynchites brevipalpis. factors generally known to influence yellow fever transmission were also studied in the ashanti region. these included ... | 1996 | 8625858 |
| some emerging issues on the malaria problem in kenya. | malaria in kenya has been characterised by marked variability in its epidemiology, partly reflecting the obstacles and progress made in the control strategies. the impact of anti-vector activities in the 1970s and before have been observed for variable lengths of time afterwards. malaria has re-emerged in areas previously with little or no transmission. the recovery of infective anopheles gambiae vector in higher altitudes affirms the potential for transmission in areas where epidemics have been ... | 1996 | 8625864 |
| evolutionary conservation and molecular characteristics of repetitive sequences of drosophila koepferae. | thirteen middle repetitive dna clones obtained from the genome of drosophila koepferae have been tested for their evolutionary conservation in the other seven species of the buzzatii and martensis clusters (repleta group). all but two of these clones exhibit qualitatively similar patterns of hybridization in the eight species. the average interspecific hybridization signal is 85 per cent of that found intraspecifically, ranging from 73 to 93 per cent. partial sequencing of six of these clones ha ... | 1996 | 8626221 |
| 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 ... | 1996 | 8627478 |
| molecular characterization of the anopheles gambiae 2l telomeric region via an integrated transgene. | a drosophila p-element derivative (puchsneo) integrated into the telomeric region of the left arm of the second chromosome of anopheles gambiae was used to clone the proximally flanking an. gambiae sequences. molecular analyses revealed that the puchsneo construct was partially duplicated and had integrated into a subterminal minisatellite. this satellite has a repeat unit of 820 bp and is located exclusively at the tip of 2l. no sequence similarity to subterminal minisatellites from other dipte ... | 1996 | 8630530 |
| evolution of the mitochondrial dna control region in the anopheles gambiae complex. | we have sequenced the at-rich control region of the mitochondrial dna (mtdna) of six species in the afrotropical anopheles gambiae complex and the closely related a. christyi. contrary to expectations, the at-rich region in this group is evolving rather slowly, more slowly than the third position of mtdna protein-coding genes. despite being relatively conserved between species, we detected intraspecific and intra-individual (heteroplasmy) variation in this region. phylogenetically, we found we c ... | 1996 | 8630535 |
| isolation and characterization of three serine protease genes in the mosquito anopheles gambiae. | three genes encoding serine proteases (sp6a, sp6t and sp8t) were isolated from the malaria mosquito an. gambiae. the proteins that are conceptually translated from these genes contain all amino acids that have been described for this class of proteolytic enzymes, namely the his, asp and ser residues at the active site, and the six cysteine residues that form the three disulphide bridges in invertebrate serine proteases. the genes are expressed at low levels and the transcripts were detected only ... | 1996 | 8630536 |
| some observations on the biting behavior of anopheles gambiae s.s., anopheles arabiensis, and anopheles funestus and their implications for malaria control. | studies were carried out in three villages in western kenya on the biting behavior of anopheles gambiae s.s., anopheles arabiensis, and anopheles funestus. blood feeding behavior and departure from houses were studied under the impact of permethrin-impregnated eaves-sisal curtains. only 2-13% of the female vector population was collected biting before 2200 hr. over 90% of the villagers went to bed by 2100 hr. an. funestus was 6.6-8.2 times more likely to bite people indoors than outdoors, while ... | 1996 | 8631382 |
| the nigerian i/cdc strain of plasmodium ovale in chimpanzees. | the chimpanzee is the only animal host currently available that can support the development of the human malaria parasite plasmodium ovale. thirty-one infections with the nigerian i/cdc strain were induced in splenectomized chimpanzees. maximum parasite counts ranged from 1,240 to 127,224/microliters. infections were transient and unpredictable. anopheles stephensi, anopheles gambiae, anopheles freeborni, and anopheles dirus mosquitoes were infected by feeding through parafilm membranes on hepar ... | 1996 | 8636850 |
| [experimental infections of anopheles gambiae with plasmodium falciparum gametocytes: epidemiology of malaria man-vector transmission in the urban milieu]. | | 1995 | 8649244 |
| [bred anopheles gambiae infectivity of a population sample living in a malaria endemic zone]. | | 1995 | 8649246 |
| [the utilization of molecular biological tools in the study of malaria transmission: example of programs conducted in senegal]. | some informations about malaria transmission, which has until nox difficult to get, can be obtained thanks to the use of molecular biology tools, pcr mainly. in senegal, we use that technique to solve two kinds of problems: -identification of species of the anopheles gambiae complex: pcr technique is useful compared to other diagnostic methods (chromosome pattern, dna probes, etc.) because it enables quickly and simply identification of captured anopheles from the dna contained in their legs. th ... | 1995 | 8649267 |
| pantropic retroviral vectors integrate and express in cells of the malaria mosquito, anopheles gambiae. | the lack of efficient mechanisms for stable genetic transformation of medically important insects, such as anopheline mosquitoes, is the single most important impediment to progress in identifying novel control strategies. currently available techniques for foreign gene expression in insect cells in culture lack the benefit of stable inheritance conferred by integration. to overcome this problem, a new class of pantropic retroviral vectors has been developed in which the amphotropic envelope is ... | 1996 | 8650240 |
| distribution of t1, q, pegasus and mariner transposable elements on the polytene chromosomes of pest, a standard strain of anopheles gambiae. | the chromosomal locations of four families of transposable elements, t1, q, pegasus and mariner, have been determined by in situ hybridization to polytene chromosomes of ovarian nurse cells of the mosquito anopheles gambiae. as part of this effort, we have developed a vigorous pink-eyed laboratory strain of a. gambiae (pest), rendered homozygous standard for chromosomal inversions on all autosomes. ten different individuals of this strain were studied with each transposable element probe. the av ... | 1996 | 8662251 |
| the polyubiquitin gene of the mosquito anopheles gambiae: structure and expression. | the polyubiquitin gene from the mosquito anopheles gambiae has been cloned and sequenced, and its structure is reported along with sequence analysis results. the gene consists of approximately seven tandem head-to-tail repeat units of the seventy-six amino acid-coding ubiquitin monomer. it is expressed constitutively in larvae, pupae and adults of an. gambiae, as well as in a cell line derived from this mosquito species. a probe made from a dna fragment containing the coding region of the gene r ... | 1996 | 8673261 |
| short report: simultaneous detection by polymerase chain reaction of mosquito species and plasmodium falciparum infection in anopheles gambiae sensu lato. | total rna purified from anopheles gambiae mosquitoes can be used for detection of both 1) infection by plasmodium falciparum using a reverse transcriptase-polymerase chain reaction (rt-pcr) assay specific for p. falciparum ribosomal rna (rrna) of sporogonic stage parasites, and 2) mosquito species using a pcr assay that distinguishes members of the anopheles gambiae complex. | 1996 | 8686783 |
| enzyme polymorphisms in the anopheles gambiae (diptera:culicidae) complex related to feeding and resting behavior in the imbo valley, burundi. | a cellulose acetate electrophoresis system was used to study the anopheles gambiae complex at 2 villages in central imbo valley and at 1 village in south imbo valley (burundi). in south imbo, only an. gambiae giles sensu stricto was present. in the drier central imbo, the dominant species was an. arabiensis patton (97.5%); an. gambiae s.s. represented only 2.5%. both species were separated readily by odh and mpi, because they did not share alleles at those loci. indoor resting an. gambiae s.s. f ... | 1996 | 8699447 |
| effects of sugar availability on the blood-feeding behavior of anopheles gambiae (diptera:culicidae). | blood-feeding behavior and survivorship of individual anopheles gambiae giles females were observed daily in cohorts with either access to sugar (n = 76) or without sugar (n = 80). individual mosquitoes were allowed to feed daily on an anesthetized mouse. mosquitoes provided with sugar lived on average almost 3 d longer than females without sugar (19.0 versus 16.2 d). after stratification by age, mosquitoes in the youngest (5-12 d) and middle (13-19 d) age strata showed no differences in blood-f ... | 1996 | 8699455 |
| frequent blood-feeding and restrictive sugar-feeding behavior enhance the malaria vector potential of anopheles gambiae s.l. and an. funestus (diptera:culicidae) in western kenya. | natural blood-feeding and sugar-feeding behaviors were investigated for populations of anopheles gambiae s.l. and an. funestus giles at 2 sites in western kenya. during peak levels of malaria parasite transmission, > 85% of 1,569 indoor-resting females contained fresh blood meals. findings that up to 55.4% of blood-fed resting females and 72.0% of host-seeking females had either stage iv or v oocytes provided strong evidence that females were refeeding before oviposition. such gonotrophic discor ... | 1996 | 8699456 |
| an integrated genetic map of the african human malaria vector mosquito, anopheles gambiae. | we present a genetic map based on microsatellite polymorphisms for the african human malaria vector, anopheles gambiae. polymorphisms in laboratory strains were detected for 89% of the tested microsatellite markers. genotyping was performed for individual mosquitos from 13 backcross families that included 679 progeny. three linkage groups were identified, corresponding to the three chromosomes. we added 22 new markers to the existing x chromosome map, for a total of 46 microsatellite markers spa ... | 1996 | 8725240 |
| integrated genetic map of anopheles gambiae: use of rapd polymorphisms for genetic, cytogenetic and sts landmarks. | randomly amplified polymorphic dna (rapd) markers have been integrated in the genetic and cytogenetic maps of the malaria vector mosquito, anopheles gambiae. fifteen of these markers were mapped by recombination, relative to microsatellite markers that had been mapped previously. thirty-four gel-purified rapd bands were cloned and sequenced, generating sequence tagged sites (stss) that can be used as entry points to the a. gambiae genome. thirty one of these stss were localized on nurse cell pol ... | 1996 | 8725241 |
| measurement by membrane feeding of reduction in plasmodium falciparum transmission induced by endemic sera. | the standard laboratory test for reduction in malaria transmission is based on the measurement of oocyst numbers in mosquitoes fed on blood meals containing test and control sera. interpretation of the results, however, is often hampered by the large variation in numbers of infected mosquitoes and oocysts. the objective of this study was to compare 3 measures for the assessment of transmission reduction (so-called r values) and to define the experimental criteria that allow interpretation of the ... | 1996 | 8730302 |
| the late biting habit of parous anopheles mosquitoes and pre-bedtime exposure of humans to infective female mosquitoes. | using the all-night landing catch method (18:00-06:00) we showed, for anopheles gambiae in sierra leone and a. punctulatus in papua new guinea, that parous females have a tendency to bite later than nulliparous ones. the biting habit of sporozoite-infected a. punctulatus was also investigated. the sporozoite rates for plasmodium falciparum and p. vivax were 1.8 and 1.4% respectively, but only one (1.3%) of 76 females infected with p. falciparum was caught between 18:00 and 21:00. a significantly ... | 1996 | 8730303 |
| polymerase chain reaction used to describe larval habitat use by anopheles gambiae complex (diptera: culicidae) in the environs of ifakara, tanzania. | larvae of the anopheles gambiae complex were collected in and around the town of ifakara, southern tanzania during the wet season of 1994 and identified to species by polymerase chain reaction. all but 1 surface pool contained mixed populations of an. gambiae and an. arabiensis larvae. the 2 species varied among locations rather than types of water. an. arabiensis predominated in pools close to cattle. the numbers of identified early instars of both species were similar, but more an. gambiae 4th ... | 1996 | 8742521 |
| variability in the relationship between weight and wing length of anopheles gambiae (diptera: culicidae). | the relationship between wing length and body weight of female anopheles gambiae giles reared at 3 densities and at 3 temperatures was examined. although overall, weight was proportional to wing length raised to the 4th power, the relationship within treatments was linear. the slope of the regression line varied significantly among treatments. therefore, wing length of mosquitoes caught from field populations may not be an adequate measure of body weight if the conditions under which the mosquit ... | 1996 | 8742532 |
| perennial transmission of malaria by the anopheles gambiae complex in a north sudan savanna area of mali. | | 1996 | 8744717 |
| the use of synthetic dna probes for the field identification of members of the anopheles gambiae complex. | | 1996 | 8751367 |
| pcr of the ribosomal dna intergenic spacer regions as a method for identifying mosquitoes in the anopheles gambiae complex. | | 1996 | 8751368 |
| genetic differentiation of anopheles gambiae populations from east and west africa: comparison of microsatellite and allozyme loci. | genetic variation of anopheles gambiae was analysed to assess interpopulation divergence over a 6000 km distance using short tandem repeat (microsatellite) loci and allozyme loci. differentiation of populations from kenya and senegal measured by allele length variation at five microsatellite loci was compared with estimates calculated from published data on six allozyme loci (miles, 1978). the average wright's fst of microsatellite loci (0.016) was lower than that of allozymes (0.036). slatkin's ... | 1996 | 8760401 |
| [malaria in mayotte: past, present and future]. | discovered as a form of intermittent fevers in 1852 and confirmed by blin in 1905, malaria has had a large impact on the mortality and the morbidity of the population living in mayotte until 1976. an evolutionary analysis of the disease shows two distinct periods. the first period between 1792 and 1974 concerns the date of introduction of malaria to the island and the limited actions of the fight against malaria led by different organizations. the second period from 1976, when the program was es ... | 1995 | 8784540 |
| [epidemiology and control of malaria in the federal islamic republic of comoros]. | malaria constitutes a major public health problem in the federal islamic republic of comoros. this problem is relatively recent from the historical point of view of the archipelago. it represents 15 to 30% of the hospitalization cases and 15 to 20% of the registered deaths in the pediatric services. the epidemiological data collected show that the characteristics of malaria transmission continue for the stable type; however, the epidemiological situation varies from one island to another. the pr ... | 1995 | 8784541 |
| [control of malaria re-emergence in reunion]. | réunion is currently posed with the operational problem of the last phase of the struggle against malaria, that is the consolidation and the maintenance of the state of cradication. the native parasite was eliminated, but the risk of resurgence of malaria remains on the island. this risk is even increasing from year to year because of the following: 1) the regular increase of the number of travellers originating from countries with malaria and consequently, the increase in the number of imported ... | 1995 | 8784548 |
| temporal and spatial distribution of anopheline mosquitos in an ethiopian village: implications for malaria control strategies. | the spatial and temporal distribution of anopheles gambiae mosquitos in houses in the village of sille in ethiopia was monitored in 1990-91. monthly mosquito densities in over 300 houses were obtained, and the data for each month were plotted on maps, which indicated clustering of mosquitos within the village. spatial analysis using "kriging" techniques demonstrated clustering towards the edges of the village, the pattern of which changed with time. for example, the low density of mosquitos in o ... | 1996 | 8789928 |
| inducible immune factors of the vector mosquito anopheles gambiae: biochemical purification of a defensin antibacterial peptide and molecular cloning of preprodefensin cdna. | larvae of the mosquito vector of human malaria, anopheles gambiae, were inoculated with bacteria and extracts were biochemically fractionated by reverse-phase hplc. multiple induced polypeptides and antibacterial activities were observed following bacterial infection, including a member of the insect defensin family of antibacterial proteins. a cdna encoding an. gambiae preprodefensin was isolated using pcr primers based on phylogenetically conserved sequences. the mature peptide is highly conse ... | 1996 | 8799739 |
| occurrence of an unusual polymerase chain reaction product during identification of anopheles gambiae sibling species (diptera: culicidae). | using the polymerase chain reaction (pcr) for species differentiation within the anopheles gambiae complex, we examined several hundred cameroonian mosquito specimens. applying an approved routine protocol for dna extraction and pcr conditions, apart from the indubitable identification of most of the specimens, we came across ten pcr products that did not correspond in length to any of the hitherto known amplification products of the sibling species. sequencing experiments showed the ten product ... | 1996 | 8801561 |
| physical map of the malaria vector anopheles gambiae. | random cdna clones, cosmid clones and rapd polymorphic fragments have been localized by in situ hybridization to the ovarian nurse cell polytene chromosomes of the malaria vector anopheles gambiae. we thus established 85 molecular markers for 110 sites within the whole a. gambiae polytene chromosome complement. the cdna clones analyzed were isolated at random, and their exact localizations were determined by in situ hybridization. for 15 of the cdna clones, a partial nucleotide sequence has been ... | 1996 | 8807302 |
| inversion monophyly in african anopheline malaria vectors. | the african anopheles gambiae complex of six sibling species has many polymorphic and fixed paracentric inversions detectable in polytene chromosomes. these have been used to infer phylogenetic relationships as classically done with drosophila. two species, a. gambiae and a. merus, were thought to be sister taxa based on a shared x inversion designated xag. recent dna data have conflicted with this phylogenetic inference as they have supported a sister taxa relationship of a. gambiae and a. arab ... | 1996 | 8807303 |
| permeability of intact and dechorionated eggs of the anopheles mosquito to water vapor and liquid water: a comparison with drosophila. | as an initial step in the development of cryopreservation methods for anopheles gambiae embryos, we determined the permeability of intact and dechorionated a. gambiae embryos to water and ethylene glycol and compared those permeabilities with those of drosophila melanogaster embryos. most studies were conducted on embryos allowed to develop for 8 h at 26 degrees c or 15 h at 17 degrees c. intact a. gambiae embryos are some 50 times more permeable to water vapor than are d. melanogaster embryos; ... | 1996 | 8812093 |
| permeabilization of eggs of the malaria mosquito anopheles gambiae. | although anopheles gambiae embryos that have developed for 15 h at 17 degrees c are slightly permeable to water, they are impermeable to ethylene glycol, the cryoprotectant used in the cryopreservation of drosophila melanogaster embryos. success in cryopreservation requires that they be made permeable to protective solutes. permeabilization of d. melanogaster was achieved by 1) dechorionation with 50% clorox (household bleach) followed by 2) a water flush; 3) immersion in isopropyl alcohol to re ... | 1996 | 8812094 |
| cloning and characterization of the white gene from anopheles gambiae. | a 14 kb region of genomic dna containing the x-linked anopheles gambiae eye colour gene, white, was cloned and sequenced. genomic clones containing distinct white+ alleles were polymorphic for the insertion of a small transposable element in intron 3, and differed at 1% of nucleotide positions compared. sequence was also determined from a rare 2914 bp cdna. comparison of cdna and genomic sequences established an intron-exon structure distinct from drosophila white. despite a common trend in anop ... | 1995 | 8825759 |
| malaria in côte d'ivoire wet savannah region: the entomological input. | a two years study has been carried out in alloukoukro, a traditional wet savannah village in the central region of côte d'ivoire. the productive breeding sites of malaria vectors are natural puddles and some man-made shelters around the village. 576 man-nights of capture have identified anopheles gambiae s.l. and an. funestus as vectors of malaria in the study area. the low densities of an. phaorensis and an coustani implies that their possible role in transmission is very negligible. an. gambia ... | 1995 | 8826108 |
| evaluation of a eucalyptus-based repellent against anopheles spp. in tanzania. | a eucalyptus-based insect repellent (pmd) with the principal active ingredient p-menthane-3,8-diol was evaluated in the field in comparison with deet. in human landing catches in tanzania, 3 formulations of pmd were tested against anopheles gambiae and an. funestus. repellents, applied to the legs and feet at doses chosen as used in practice, gave complete protection from biting for between 6 and 7.75 h, depending upon the formulation type, with no significant difference between pmd and deet in ... | 1996 | 8827599 |
| the polymerase chain reaction method as a tool for identifying members of the anopheles gambiae complex (diptera:culicidae) in northeastern tanzania. | polymerase chain reaction (pcr) primers developed at the centers for disease control in atlanta for the identification of members of the anopheles (cellia) gambiae giles complex were tested on material collected in the bagamoyo and muheza districts of northeastern tanzania. part of the sample from bagamoyo was chromosomally identified and correlated with the pcr identifications. this sample contained 170 anopheles arabiensis, 328 an. gambiae, and 58 anopheles merus, of which 121, 237, and 54 spe ... | 1996 | 8827604 |
| comparison of different insecticides and fabrics for anti-mosquito bednets and curtains. | various formulations of six insecticides (a carbamate and five pyrethroids), were impregnated into bednets and curtains made from cotton, polyester, polyethylene or polypropylene fabric. for bioassays of insecticidal efficacy, female anopheles gambiae mosquitoes were made to walk on the fabrics for 3 min and mortality was scored after 24 h. the main concentrations tested were: bendiocarb 400 mg/m2, cyfluthrin 30-50 mg/m2, deltamethrin 15-25 mg/m2, etofenprox 200 mg/m2, lambda-cyhalothrin 5-15 mg ... | 1996 | 8834736 |
| long-term use of permethrin-impregnated nets does not increase anopheles gambiae permethrin tolerance. | previous use of permethrin-impregnated bednets (mosquito nets) and curtains in four kenyan villages for one year, 1990-91, raised the permethrin lt50 of anopheles gambiae to 2.4-fold above its baseline value, designated permethrin tolerance (pt), as measured by exposure to 0.25% permethrin-impregnated papers in w.h.o. test-kits. during 1992-93, with ongoing use of permethrin-impregnated nets and curtains, pt regressed slightly compared with the contemporary susceptibility level of an.gambiae fro ... | 1996 | 8834745 |
| rapid isolation of anopheline mosquito eye-colour mutants, based on larval colour change. | a method is presented for the rapid isolation of eye-colour mutants in anopheline mosquitoes based on their inability to undergo a background-stimulated morphological colour change. for application of this method, larval mosquitoes, whose grandfathers had been mutagenized, were reared in black containers and examined with the naked eye en masse during the third or fourth instar. the vast majority of larvae became dark-coloured; however, rare exceptional pale larvae were observed and examined ind ... | 1996 | 8834748 |
| density, survival and dispersal of anopheles gambiae complex mosquitoes in a west african sudan savanna village. | to obtain information on adult populations of afrotropical malaria vector mosquitoes, mark-release-recapture experiments were performed with anopheles females collected from indoor resting-sites in a savanna area near ouagadougou, burkina faso, during september 1991 and 1992. results were used to estimate the absolute population densities, daily survival rates, and dispersal parameters of malaria vectors in that area. in 1991 a total of 7260 female anopheles were marked and released, of which 10 ... | 1996 | 8887330 |
| mosquito responses to carbon dioxide in a west african sudan savanna village. | mosquito responses to carbon dioxide were investigated in noungou village, 30 km northeast of ouagadougou in the sudan savanna belt of burkina faso, west africa. species of primary interest were the main malaria vectors anopheles gambiae s.s. and an.arabiensis, sibling species belonging to the an.gambiae complex. data for an.funestus, an.pharoensis, culex quinquefasciatus and mansonia uniformis were also analysed. carbon dioxide was used at concentrations of 0.04-0.6% (cf. 0.03% ambient concentr ... | 1996 | 8887331 |
| identification of electrophysiologically-active compounds for the malaria mosquito, anopheles gambiae, in human sweat extracts. | human sweat samples were chemically fractionated into acid and non-acid components. the most abundant volatile compounds present in the fractions were identified by linked gas chromatography mass spectrometry. the acid fractions were found to be composed of a range of twenty aliphatic and three aromatic carboxylic acids ranging, on average, from 0.02 to 20 micrograms per ml of sweat sampled. non-acid fractions were found to contain: 6-methyl-5-hepten-2-one, 1-octen-3-ol, decanal, benzyl alcohol, ... | 1996 | 8887339 |
| immune factor gambif1, a new rel family member from the human malaria vector, anopheles gambiae. | a novel rel family member, gambif1 (gambiae immune factor 1), has been cloned from the human malaria vector, anopheles gambiae, and shown to be most similar to drosophila dorsal and dif. gambif1 protein is translocated to the nucleus in fat body cells in response to bacterial challenge, although the mrna is present at low levels at all developmental stages and is not induced by infection. dna binding activity to the kappab-like sites in the a.gambiae defensin and the drosophila diptericin and ce ... | 1996 | 8887560 |