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induction of trypanosoma cruzi metacyclogenesis in the gut of the hematophagous insect vector, rhodnius prolixus, by hemoglobin and peptides carrying alpha d-globin sequences.trypanosoma cruzi, a protozoan responsible for the american trypanosomiasis (chagas disease), multiplies and differentiates in the gut of triatomine insect vectors. the effects of hemoglobin and synthetic peptides carrying alpha d-globin fragments on both the growth and the transformation of t. cruzi epimastigotes (noninfective) into metacyclic trypmastigotes (infective forms) were studied. this differentiation in the insect's gut is expressed when hemoglobin and synthetic peptides corresponding ...19957498422
density estimates of the domestic vector of chagas disease, rhodnius prolixus stål (hemiptera: reduviidae), in rural houses in venezuela.we reported the use of the timed manual method, routinely employed as an indicator to the relative abundance of domestic triatomine bugs, to estimate their absolute density in houses. a team of six people collected rhodnius prolixus stål bugs from the walls and roofs of 14 typical palm-leaf rural houses located in cojedes, venezuela, spending 40 minutes searching in each house. one day after these manual collections, all the houses were demolished and the number of triatomine bugs were identifie ...19957614667
a salivary nitrophorin (nitric-oxide-carrying hemoprotein) in the bedbug cimex lectularius.salivary gland homogenate of the bedbug cimex lectularius caused vasodilation of the preconstricted rabbit aortic ring in the absence of endothelium. vasodilation was augmented in the presence of superoxide dismutase and inhibited in the presence of methylene blue. utilization of the griess reaction indicated the presence of reactive nitrogen equivalents of the order of 337 +/- 57 pg equivalent no2- per pair of salivary glands (mean +/- s.e.m.; n = 3). salivary gland homogenates have a nitrosyl- ...19957658188
genetic variability and differentiation between populations of rhodnius prolixus and r. pallescens, vectors of chagas' disease in colombia.enzyme polymorphism in rhodnius prolixus and r. pallescens (hemiptera, reduviidae), principal vectors of chagas' disease in colombia, was analyzed using starch gel electrophoresis. three geographic locations were sampled in order to determine gene flow between populations and to characterize intra- and interspecific differences. of 25 enzymes assayed 10 were successfully resolved and then used to score the genetic variation. the enzymes pepd, gpi, pgm and icd were useful to differentiate these s ...19958544739
a heme-binding protein from hemolymph and oocytes of the blood-sucking insect, rhodnius prolixus. isolation and characterization.a heme-binding protein has been isolated and characterized from both the hemolymph and oocytes of the blood-sucking insect, rhodnius prolixus. the protein from both sources is identical in most aspects studied. the rhodnius heme-binding protein (rhbp) is composed of a single 15-kda polypeptide chain coiled in a highly alpha-helical structure which binds non-covalently one heme/polypeptide chain. this rhbp is not produced by limited degradation of hemoglobin from the vertebrate host, since specif ...19957738030
trypanosoma cruzi and trypanosoma rangeli: interplay with hemolymph components of rhodnius prolixus.studies were carried out on the course of infection of trypanosoma cruzi (clone dm28c) and trypanosoma rangeli (clone san agustin) and their interactions with hemolymph components of rhodnius prolixus. these parasites when inoculated into the hemocoel of adult r. prolixus (i) had different courses of infection (t. rangeli had high rates of both multiplication and infection and t. cruzi had no division and disappeared soon from the hemolymph); (ii) induced high but no differential increases in ly ...19957745280
trypanosoma cruzi: metacyclogenesis in vitro--i. changes in the properties of metacyclic trypomastigotes maintained in the laboratory by different methods.in this work we have studied the modifications in the biological properties of trypanosoma cruzi when the parasite is maintained for a long time in axenic culture. the studies were done with a clone from an avirulent strain (dm30l) and a non-cloned virulent strain (ep) of t. cruzi. both parasites were maintained, for at least three years, by successive triatomine/mouse alternate passage (control condition), or by serial passage in axenic medium (culture condition), or only in the mouse (mouse co ...19947885254
a kazal-type inhibitor of human mast cell tryptase: isolation from the medical leech hirudo medicinalis, characterization, and sequence analysis.human tryptase, a tetrameric proteinase expressed by mast cells, is virtually unique among the serine proteinases as it is not inhibited by any proteinaceous inhibitor tested so far. we have now isolated, sequenced, and characterized an inhibitor of human tryptase from the medical leech hirudo medicinalis. ldti (leech-derived tryptase inhibitor) was purified to apparent homogeneity by cation exchange and affinity chromatography. amino acid sequencing of the protein consisting of 46 residues (m(r ...19947888081
high affinity histamine-binding and antihistaminic activity of the salivary nitric oxide-carrying heme protein (nitrophorin) of rhodnius prolixus.the salivary glands of rhodnius prolixus contain a nitrosyl-heme protein, named nitrophorin, that releases the vasodilatory and antiplatelet compound nitric oxide (no). because imidazole compounds such as histamine can interact with fe(iii) heme proteins, we investigated whether such substances could interact with rhodnius nitrophorins. both imidazole and histamine, but not histidine can produce full of the difference spectra of the soret band in the 1-3 microm concentration range (at a heme pro ...19947964498
randomly amplified polymorphic dna (rapd) and isoenzyme analysis of trypanosoma rangeli strains.sixteen trypanosoma rangeli strains were compared by isoenzyme and randomly amplified polymorphic dna (rapd) analysis. eight strains were isolated from either rhodnius prolixus or homo sapiens from honduras, colombia and venezuela. another eight strains were isolated from either panstrongylus megistus or the rodent echimys dasythrix from the state of santa catarina, southern brazil. all six t. rangeli strains isolated from p. megistus were co-infections with trypanosoma cruzi, demonstrating an o ...19948049688
structural specialization in the flagellum of the spermatozoon of the bloodsucking bug (rhodnius prolixus; hemiptera, reduviidae).spermatozoa of the triatomideo rhodnius prolixus possess an axoneme with a 9 + 9 + 2 microtubule pattern and two mitochondrial derivatives. bridges occur between axoneme and mitochondrial derivatives. two paracrystalline structures embedded in amorphous regions were observed in the mitochondrial derivative. the use of the negative staining technique shows a zig-zag profile in the mitochondrial derivatives due to infolding to the cristae, regularly spaced with approximately 50 nm. this spacing is ...19948073413
morphometric variability in the chagas' disease vector rhodnius prolixus.morphometric variability was studied in six domestic venezuelan populations of the blood-sucking bug rhodnius prolixus stal 1897 (reduviidae, triatominae) and in a sylvatic population identified as r. robustus larrousse 1927. evidence is here provided by both uni- and multifactorial analyses of extensive variation of morphological traits between the r. prolixus populations studied. regardless the geographic or climatic environmental factor tested, none can be retained in a selective model accoun ...19948080655
rhodnius prolixus: salivary antihemostatic components decrease with trypanosoma rangeli infection.feeding behavior and some antihemostatic properties of the saliva of rhodnius prolixus infected with trypanosoma rangeli were studied and compared with those of uninfected controls. insects with salivary gland infection pierced host skin more often and drew less blood and at a lower rate than controls when feeding on a rabbit. none of these differences was observed when feeding was performed through a membrane feeder. salivary gland homogenates from infected insects, at 30 days after feeding/inf ...19948162960
immunogold labelling of serotonin-like and fmrfamide-like immunoreactive material in neurohaemal areas on abdominal nerves of rhodnius prolixus.the ultrastructure of neurohaemal areas on abdominal nerves of the blood-sucking bug rhodnius prolixus was investigated. four types of axon terminals were found, distinguished by the morphology of their neurosecretory granules. by use of post-embedding immunogold labelling, granules in type i axon terminals were shown to contain serotonin-like immunoreactive material, and granules in type ii axon terminals were shown to contain fmrfamide-like immunoreactive material. there was no colocalization ...19947954695
protein phosphorylation in rhodnius prolixus oocytes: identification of a type ii casein kinase.a protein kinase activity in chorionated oocytes of rhodnius prolixus phosphorylates in vitro vitellin (vt), the major yolk protein. phosphatase inhibitors including naf, sodium vanadate, beta-glycerophosphate and okadaic acid did not alter the protein phosphorylation profile to a visible extent. among the exogenous protein substrates tested, casein was readily phosphorylated, but histones were not. several different protein kinase activators, including camp, ca2+ plus calmodulin, ca2+ plus diol ...199311446384
ionic basis of bioelectric currents during oogenesis in an insect.transmembrane bioelectric currents around insect ovaries are well documented but as yet poorly understood. in the present study we describe the ionic basis of such currents around the telotrophic ovariole of rhodnius prolixus using a two-dimensional vibrating probe and ion-substituted media and inhibitors. current efflux from the base and apex of the terminal follicle is carried by electrogenic na+ transport, and the return circuit over the middle of the terminal follicle is the result of na+ in ...19937688328
dynamics of the oocyte cortical cytoskeleton during oogenesis in rhodnius prolixus.the oocyte cortex undergoes dramatic changes during oogenesis in rhodnius prolixus. despite numerous studies examining oogenesis in the telotrophic ovariole, none has investigated the ultrastructural details of the oocyte cortex, in particular, the lateral cortical cytoskeleton. indirect immunofluorescent staining of sections, rhodamine phalloidin staining of whole mounts and scanning and transmission em of permeabilized and unpermeabilized preparations revealed the dynamic changes of the oocyte ...199318621240
cdna cloning and expression of rhodnius prolixus vitellogenin.it was shown that rhodnius prolixus vitellogenin (vg) is synthesized as precursors of 205 and 190 kda. each vg subunit is antigenically related to a domain in the precursor molecules. since vg has been previously detected in r. prolixus male adults, protein synthesis by fat bodies from 5th instar male nymphs was investigated and no vg synthesis could be detected. also, a 6.1 kb rna is present in female adults but not in 5th instar male nymphs. therefore, cdnas from female adult and 5th instar ma ...19938508188
reversible binding of nitric oxide by a salivary heme protein from a bloodsucking insect.the bloodsucking bug rhodnius prolixus has a salivary vasodilator, previously characterized as a nitrovasodilator, with salivary smooth muscle-relaxing and antiplatelet activity. rhodnius salivary glands are bright red owing to the abundance of heme proteins. electron paramagnetic resonance and optical spectroscopic experiments indicated that the salivary vasodilator is a nitrosylheme protein with an fe(iii) heme that binds nitric oxide (no) reversibly. dilution of the protein in neutral ph prom ...19938386393
the regulation of haemolymph potassium activity during initiation and maintenance of diuresis in fed rhodnius prolixus.the blood-sucking insect rhodnius prolixus rapidly eliminates a na(+)-rich k(+)-poor urine after its large meals. k(+)-rich fluid is first secreted by the upper malpighian tubules and passes to the lower tubules where most of the potassium is reabsorbed. during the initial stimulation of the tubules, the lower tubules must be activated first to avoid loss of potassium. the major element in this is that they respond more rapidly than do the upper tubules to particular hormonal concentrations rath ...19938486999
[comparative study of the susceptibility of 5 triatomine species (insecta: reduviidae) to trypanosoma cruzi infection].in order to determine the most suitable species of triatomine for xenodiagnosis of the chagas disease, five species triatomine (triatoma barberi, t. infestans, t. pallidipennis, t. phyllosoma, and rhodnius prolixus) in third and fourth instars were used to evaluate their susceptibility to one t. cruzi strain isolated in mexico. the susceptibility was determined by: a) percentage of infected triatomines, b) amount of flagellates in bug feces and c) amount of blood ingested. we found that in most ...19938209115
use of the median process of the pygophore in the identification of rhodnius nasutus, r. neglectus, r. prolixus and r. robustus (hemiptera: reduviidae).the morphometrics of the median process of the male pygophore of four species of blood-sucking bugs (rhodnius prolixus, r. robustus, r. nasutus and r. neglectus) were compared using one-way analysis of variance. although there were no significant differences in the pygophoral patterns within the r. nasutus-r. neglectus or r. prolixus-r. robustus species pairs, there were clear-cut differences between them; the median process of r. nasutus-r. neglectus is stout and subtriangular whereas that of r ...19938257239
a kazal-type inhibitor with thrombin specificity from rhodnius prolixus.a thrombin-specific inhibitor with an apparent molecular mass of 11 kda has been purified from the insect rhodnius prolixus. amino-terminal protein sequence analysis allowed the molecular cloning of the corresponding cdna. the open reading frame codes for a protein of about 103 amino acid residues and displays an internal sequence homology of residues 6-48 with residues 57-101 indicating a two-domain structure. based on the amino acid sequence the two domains exhibit high homology to protease in ...19938344906
nitric oxide synthase activity from a hematophagous insect salivary gland.the salivary glands of the hematophagous insect, rhodnius prolixus, contain a nitrosylhemeprotein that dissociates its ligand, no, to the host tissues while the insect is searching for a blood meal. we now report a salivary nitric oxide synthase activity in this insect. the activity is dependent on nadph, fad, tetrahydrobiopterin, calmodulin, ca2+, and converts arginine to citrulline while producing vasorelaxing activity. molecular sieving indicates a molecular weight of 185 kda, coeluting with ...19937689981
transfer of phospholipids from fat body to lipophorin in rhodnius prolixus.32p-labeled fat bodies (32p-fat bodies) of rhodnius prolixus females were incubated in the presence of non radioactive purified lipophorin and the release of radioactivity to the medium was analysed to answer the question of whether lipophorin is a reusable shuttle for phospholipids. the radioactivity found in the medium was associated with lipophorin phospholipids. when the 32p-fat bodies were incubated in the absence of lipophorin, only a small amount of radioactivity was released and it was n ...199211488301
lethal effect of a bait for rhodnius prolixus (hemiptera: reduviidae), the vector of chagas' disease, containing hexachlorocyclohexane (hch), under laboratory conditions.the lethal effect of a bait containing an aqueous hexachlorocyclohexane (hch) suspension at the concentration of 1g/l and maintained at room temperature was studied in the laboratory over a period of 12 weeks. the suspension was placed in a latex bag hanging inside a 1000-ml beaker tightly covered with nylon netting, and left there with no changes for 85 days. sixteen groups of r. prolixus bugs, consisting on average of 30 specimens each, were successively exposed to the bait and observed at dif ...19921285256
didelphis marsupialis: a primary reservoir of trypanosoma cruzi in urban areas of caracas, venezuela.direct blood examination and xenodiagnosis of 45 sylvatic, peridomestic or domestic mammals from the caracas valley, venezuela, revealed trypanosome infection in six of the 24 opossums, didelphis marsupialis, collected in urban areas. isolates were successfully made of trypanosomes from four of the opossums, using the parasites which developed in rhodnius prolixus fed on the infected opossums to infect nmri mice. the prepatent period, course of parasitaemia, morphology of bloodstream trypomastig ...19921304702
[the epidemiology of chagas' disease in a rural area of the city of teresina, piauí, brazil].in the rural areas of teresina, 129 triatomines were captured distributed in (a) artificial ecotopes; a house with one triatoma brasiliensis, one panstrongylus geniculatus, rhodnius pictipes, and one rhodnius prolixus and in a uninhabited chicken house (7 rhodnius nasutus). (b) natural ecotopes; pahus orbignya martiana (41 rhodnius neglectus, 33 rhodnius prolixus and 41 rhodnius nasutus) and copernicia cerifera (3 rhodnius neglectus). the 22.6% of captured triatomines were infected by flagellate ...19921308066
analytic morphometry of the trypanosoma cruzi (bolivia strain) forms found in the intestine of rhodnius prolixus. 19921308547
effects of azadirachtin on rhodnius prolixus: immunity and trypanosoma interaction.the effects of azadirachtin, a tetranortriterpenoid from the neem tree azadirachta indica j., on both immunity and trypanosoma cruzi interaction within rhodnius prolixus and other triatomines, were presented. given through a blood meal, azadirachtin affected the immune reactivity as shown by a significant reduction in numbers of hemocytes and consequently nodule formation following challenge with enterobacter cloacae beta 12, reduction in ability to produce antibacterial activities in the hemoly ...19921342719
relative susceptibility of different stages of rhodnius prolixus to the entomopathogenic hyphomycete beauveria bassiana.laboratory bioassays were conducted to determine the relative susceptibility of eggs, 1st-, 3rd-, 5th-instar nymphs and adults of rhodnius prolixus to one isolate of the entomopathogenic hyphomycete, beauveria bassiana. treatments consisted of directly spraying on insects of increasing doses of inoculum (3 x 10(2) to 3 x 10(5) conidia per cm2). mortality due to all doses of conidia was very high in the five tested stages of the target insect. experiments on eggs demonstrated that the fungal isol ...19921343645
[presence of neuraminidase in rhodnius prolixus infected with trypanosoma rangeli].using three different methods, the activity of neuraminidase was studied in the promesenteron, postmesenteron, rectal ampulla, haemolymph and salivary glands in 600 rhodnius prolixus experimentally infected with trypanosoma rangeli stock san agustín. the haemagglutination method with peanut lectin, and the fluorescence test with peanut lectin conjugated with fluorescein isothiocyanate, and the fluorescence emitted by 4-methylumbelliferone showed in all cases the presence of neuraminidase in the ...19921345317
a fmrfamide-like peptide is associated with the myotropic ovulation hormone in rhodnius prolixus.the protocerebral neurosecretory cells previously shown to be the source of the myotropin controlling ovulation in rhodnius prolixus react in an immunocytochemical assay using an antiserum against fmrfamide. when the same antiserum was injected into fed mated females at the appropriate time the timing of oviposition was delayed, but the total number of eggs developed was unaffected compared to controls injected with pre-immune rabbit serum. the titer of fmrfamide-like peptide (assayed by ria) in ...19921450451
autogeny in three species of triatominae: rhodnius prolixus, triatoma rubrovaria, and triatoma infestans (hemiptera: reduviidae).autogeny, the capacity of a female to lay eggs without having ingested any blood meal in the adult stage, was studied in three species of triatominae: triatoma infestans, triatoma rubrovaria, and rhodnius prolixus. when nymphs of t. rubrovaria and r. prolixus were fed chicken blood, autogeny occurred frequently, even with only one meal. in t. infestans autogeny was frequent as well, but demanded at least two nymphal blood meals. total number of autogenic eggs was positively correlated with the b ...19921495041
transformation of an insect symbiont and expression of a foreign gene in the chagas' disease vector rhodnius prolixus.a shuttle plasmid was developed that is capable of replicating both in escherichia coli and in rhodococcus rhodnii, a bacterial symbiont of the chagas' disease vector rhodnius prolixus. we have been able to transform r. rhodnii with this plasmid, infect aposymbiotic r. prolixus with the transformed symbionts, select with the antibiotic thiostrepton, and re-isolate genetically altered symbionts from the insects following successive molts. symbiotic bacteria are potentially valuable as vehicles fo ...19921539755
isozyme variability and differentiation between rhodnius prolixus, r.robustus and r.pictipes, vectors of chagas disease in venezuela.enzyme polymorphism in triatomine bugs of the genus rhodnius (hemiptera: reduviidae), vectors of chagas disease, is analysed using both starch and polyacrylamide gel electrophoresis. out of forty-five enzymes assayed, the electromorphs of seventeen of them: ao, ca, dia, es, es-a, fh, gpd, g6pd, gpi, mdh, me, 6pgd, pgm, acon, acph, lap and sod, involving twenty-two putative structural loci, were scorable. these gene-enzyme systems were therefore selected for routine characterization of r.prolixus ...19921600225
spatial and temporal transcellular current patterns during oogenesis.we have used the two-dimensional vibrating probe to examine spatial and temporal patterns in the transcellular current flow around telotrophic ovarioles of the insect rhodnius prolixus. we demonstrate a dynamic pattern of currents which correlates with various stages of vitellogenesis. asymmetries exist in the radial current pattern around intact ovarioles, particularly around the terminal follicle, and may correlate with early developmental axes. the extra-cellular current pattern is largely re ...19921397687
insulin-like immunoreactivity and molting in rhodnius prolixus.two prominent cells were observed when fifth stage rhodnius female larval brains were stained with anti-insulin serum. the staining intensity of these cells varied during the instar, being lowest on day 1 and days 5 and 6 after feeding. injection of anti-insulin serum into 5th stage larvae immediately after feeding and on days 4 and 5 in females and on days 5 and 6 in males prevented molting. control antiserum had no effect on the molting process. injections at other times during the instar had ...19921601272
cell proliferation and rearrangement in the development of the malpighian tubules of the hemipteran, rhodnius prolixus.the pattern of cell activities resulting in the generation of a simple tubular epithelium, the malpighian tubules of rhodnius prolixus, is examined during embryogenesis. the anlage of the tubules is shown to be of ectodermal origin. an evolving pattern of cycling cells in the primordia is revealed using the immunocytochemical localization of a substituted nucleotide, budr. a cell unique to each tubule is shown not to enter the cell cycle but to be required for the proliferation of the remaining ...19921551481
in vitro photosensitivity of ecdysteroid synthesis by prothoracic glands of rhodnius prolixus (hemiptera).the effects of light:dark transitions on in vitro ecdysteroid synthesis by prothoracic glands (pgs) of male fifth instar rhodnius have been studied. pgs were rendered arrhythmic by prolonged maintenance of the animals in continuous light (ll). pgs were then explanted and ecdysteroid synthesis was measured hourly by radioimmunoassay. pgs were transferred from ll to darkness at various times after explanation and hourly synthesis was measured for several more hours. transfer of pgs to darkness in ...19921505717
role of phospholipids in the lipophorin particles of rhodnius prolixus.the lipophorin of rhodnius prolixus metabolically labelled with 32p exclusively in the phospholipid moiety was purified on a potassium bromide gradient and treated with phospholipase a2 in the presence of an excess of fatty acid-free albumin. the treatment completely removed the phospholipids from the particles and generated [32p]-lysophosphatidylcholine, [32p]-lysophosphatidylethanolamine, and free fatty acids that remained bound to albumin. the phospholipid-depleted lipophorin particles remain ...19921504321
identification of yolk platelet-associated hydrolases in the oocytes of rhodnius prolixus.the yolk platelets from rhodnius prolixus, a blood-sucking bug, are composed mostly of vitellin and here are shown to contain at least two hydrolytic enzymes, a phosphatase and a cathepsin d-like proteinase. both the proteinase and the phosphatase have an acid ph optimum. no hydrolytic activity was observed under alkaline or neutral conditions. among several proteinase inhibitors tested, only pepstatin could abolish vitellin breakdown in vitro. the proteinase appears to be bound to the yolk plat ...19921286200
feeding behavior of different species of chagas' disease vectors stimulated with blood sources at different temperatures.1. the feeding behavior of six triatomid species toward latex condoms filled with blood at 26 +/- 1 and 36 +/- 1 degrees c was observed for 4 h. 2. the species studied were triatoma infestans, triatoma brasiliensis, triatoma vitticeps, triatoma pseudomaculata, rhodnius prolixus and panstrongylus megistus, and 34 to 348 insects were studied in each group (average, 190). all the life stages of each species were used. 3. although most insects (80%, average for 6 species) preferred the warmer blood, ...19921304939
circadian regulation of synthesis of ecdysteroids by prothoracic glands of the insect rhodnius prolixus: evidence of a dual oscillator system.rhythmic synthesis of moulting hormones (ecdysteroids) by prothoracic glands (pgs) of the insect rhodnius prolixus during the last larval instar was studied in vitro following explantations every 4-5 hr for up to 96 hr. ecdysteroid synthesis was measured by radioimmunoassay as the quantity of ecdysteroid produced during 4 hr in vitro. a massive daily rhythm is seen, with synthesis at night being three- to fivefold higher than during the day. this rhythm of ecdysteroid synthesis by pgs free-runs ...19911879670
5-hydroxytryptamine: a second diuretic hormone in rhodnius prolixus.bioassays of 5-hydroxytryptamine (5-ht) in fifth-instar rhodnius prolixus haemolymph using calliphora salivary glands indicate that: (1) biologically active 5-ht is present, (2) in unfed animals there is not enough 5-ht to stimulate malpighian tubule fluid secretion, and (3) there is enough 5-ht soon after the initiation of feeding to stimulate rapid tubule secretion. the 5-ht receptor antagonists ketanserin and spiperone reversibly and selectively inhibit 5-ht-induced fluid secretion, indicatin ...19912051136
effects of proallatotoxins (precocenes) on the development and reproduction of rhodnius prolixus: some data.proallatotoxins, and particularly precocenes, are exceptionally promising models for studying rhodnius prolixus physiology and for comparison with other natural compounds with antihormonal activities. effects of precocenes on feeding, development and reproduction of r. prolixus are being detailed. the precocenes reveal significant effects on feeding, moulting cycle (inducing precocious metamorphosis and ecdysial stasis), and reproduction of these insects. the mechanism of action of proallatotoxi ...19911841983
lethality of triatomines (hemiptera: reduviidae), vectors of chagas' disease, feeding on blood baits containing synthetic insecticides, under laboratory conditions.a laboratory study was conducted to test the toxicity of synthetic insecticides added to defibrinated sheep blood kept at room temperature and offered as food to the following triatomine species: triatoma infestans, panstrongylus megistus, triatoma vitticeps, triatoma pseudomaculata, triatoma brasiliensis and rhodnius prolixus. the insecticides used, at a concentration of 1 g/l, were: hch, ddt, malathion and trichlorfon, and the lethalithy observed at the end of a 7-day period varied according t ...19911726952
effects of azadirachtin in rhodnius prolixus: data and hypotheses.the effects of azadirachtin a, a tetranortriterpenoid from the neem tree azadirachta indica j., on both development and interaction between trypanosoma cruzi, the causative agent of chagas' disease, and its vector rhodnius prolixus were studied. given through a blood meal, a dose-response relationship of azadirachtin was established using antifeedant effect and ecdysis inhibition as effective parameters. a single dose of azadirachtin a was able to block the onset of mitosis in the epidermis and ...19911841982
the distribution of agglutinins and lytic activity against trypanosoma rangeli and erythrocytes in rhodnius prolixus and triatoma infestans tissue extracts and haemolymph.haemolymph, heads, salivary glands, crops, midguts, hindguts, and malpighian tubules from rhodnius prolixus and triatoma infestans were extracted in phosphate or tris buffer saline with calcium, and tested for agglutination and lytic activities by microtitration against both vertebrate erythrocytes and cultured epimastigote forms of trypanosoma rangeli. haemagglutination activity against rabbit erythrocytes was found in the crop, midgut and hindgut extracts of t. infestans but only in the haemol ...19911842412
[behavior of trypanosoma cruzi strains after passage in different triatominae species].to study the influence of the intermediate host stage on the course of mouse infection, trypanosoma cruzi belonging to the peruvian (type i), 12 sf (type ii) and colombian (type iii) strains were passaged through either rhodnius prolixus, panstrongylus megistus or triatoma infestans. t. cruzi metacyclic forms (dose 10(4)) from the different strains were obtained from each bug and inoculated into 8-10 gm mice. comparison was made in mice inoculated with blood forms. parasitaemia curves were plott ...19911845005
the prophenoloxidase system and in vitro interaction of trypanosoma rangeli with rhodnius prolixus and triatoma infestans haemolymph.the presence of the prophenoloxidase (propo) system in the haemolymph of rhodnius prolixus and triatoma infestans and the role played by trypanosoma rangeli in the in vitro activation of propo were tested. both r. prolixus and t. infestans whole blood preparations showed a very active propo system. the propo cascade of the two insect species were differentially activated by microbial-derived extracts: laminarin was a better activator of t. infestans haemolymph than of r. prolixus blood, and lipo ...19911956701
the fate of calcium in the diet of rhodnius prolixus: storage in concretion bodies in the malpighian tubules.we have investigated the fate of the large amounts of calcium ingested by rhodnius prolixus in its meals of blood. 45ca2+ injected into the haemolymph or fed to fifth-stage rhodnius reared on rabbits is accumulated at high concentrations in the cells of the upper malpighian tubules; very little is excreted from the body this 45ca2+ accumulation goes on continuously for at least 12 days and the rate of uptake is increased several-fold within 3-4 days of a meal. the extent of calcium accumulation ...19912061707
a salivary vasodilator in the blood-sucking bug, rhodnius prolixus.1. salivary gland homogenates of the blood-sucking bug, rhodnius prolixus induced transient, dose-dependent relaxation of rabbit aortic preparations pre-constricted with 200 ng ml-1 noradrenaline, 1 microgram ml-1 histamine or 20 ng ml-1 angiotensin ii. such relaxations were less marked when the aorta was constricted by 60 mm kc1. these effects were observed with as little as 0.2 microgram ml-1 of crude salivary gland protein. 2. the vasodilator effect was endothelium-independent, abolished by 5 ...19902085715
comparative studies on the growth and reproductive performances of rhodnius prolixus reared on different blood sources.host blood source was found to affect both the development and the reproductive performance of rhodnius prolixus. the insects were reared on citrated human, rabbit, chicken, sheep and horse blood sources, through a membrane feeder, during an entire life cycle, from eggs to adults. development and reproduction in terms of the number of unfed insects, number of moulting, mortality intermoulting period, number of egg/female, conversion of blood into egg (mg meal/egg) and percentage of hatch as effe ...19902134703
cyclic amp in the malpighian tubule fluid and in the urine of rhodnius prolixus.we demonstrate the presence of cyclic adenosine monophosphate (camp) in the fluid secreted by isolated malpighian tubules of rhodnius prolixus. in addition, we show that fifth-instar r. prolixus excrete camp in the urine after a meal of human blood. nonstimulated isolated malpighian tubules secrete small amounts of camp that increase about 10-fold after the addition of 5-hydroxytryptamine (5-ht). 5-ht is known to mimic r. prolixus diuretic hormone. the present findings demonstrate that 5-ht also ...19902153089
development and interactions of trypanosoma rangeli in and with the reduviid bug rhodnius prolixus.two strains of trypanosoma rangeli and three strains of rhodnius prolixus were used in various combinations to transmit the trypanosomes via the reduviid bug. a persisting infection in the midgut lumen posterior to the stomach resulted in all 2,500 bugs being third and fourth instars. infectious, metacyclic forms developed exclusively in the salivary glands; forms excreted with bug feces were noninfectious to mice. the midgut epithelium was the main barrier to transmission of the parasite. in on ...19902186407
use of total parasite dna probes for the direct detection of trypanosoma cruzi and trypanosoma rangeli in domicilliary rhodnius prolixus. 19902189249
tyrosine hydroxylase-like immunoreactivity in the brain of fifth instar rhodnius prolixus stål (hemiptera: reduviidae).the distribution of tyrosine hydroxylase-like immunoreactivity was mapped in whole-mount preparations of the brain of fifth instar rhodnius prolixus stål. immunoreactivity was limited to neuronal cell bodies and processes, which were distributed over both ventral and dorsal surfaces of the cns. the brain, excluding the optic lobes, contained about 160 tyrosine hydroxylase-like immunoreactive cells. each optic lobe contained two groups of small round cell bodies, which were too numerous to count. ...19901981216
the biochemical basis of tolerance to malathion in rhodnius prolixus.1. lc50 of malathion, fenitrothion and lindane were determined in r. prolixus and t. infestans. r. prolixus was shown to be tolerant to malathion. 2. the penetration rate of (14c)-malathion into r. prolixus and t. infestans was similar. 3. acetylcholinesterase from r. prolixus heads was 3.3-fold less sensitive to inhibition by malaoxon than the similar enzyme of t. infestans. 4. r. prolixus showed more activity of gsh-s-transferases against dcnb than t. infestans. 5. the in vitro degradation of ...19901703470
sex differences in the profiles of prothoracic gland synthetic activity and of hemolymph ecdysteroid titers during development in the last larval instar of rhodnius prolixus (hemiptera).the synthesis of ecdysteroids by prothoracic glands (pgs) of rhodnius prolixus was measured in vitro by radioimmunoassay in both male and female larvae following initiation of development in the last larval instar by a blood meal. neither ecdysteroid synthesis nor hemolymph titer differ between the sexes during the first few days following a blood meal. however, on day 4 the pgs of female larvae commence a surge of increased synthesis, while in males this surge does not commence until day 5. thi ...19892583469
a subpopulation of dorsal unpaired median neurons in the blood-feeding insect rhodnius prolixus displays serotonin-like immunoreactivity.we describe, for the first time in insects, the presence of serotonin-like immunoreactive dorsal unpaired median (dum) neurons. in unfed, untreated rhodnius prolixus, the cell bodies of these dum neurons displayed only faint serotonin-like immunofluorescence without any detectable fluorescence in the axons. there was, however, an extensive serotonin-like immunoreactive peripheral complex. we have enhanced the immunostaining of the cell bodies and axons of these dum neurons by using 5,7-dihydroxy ...19892681279
developmental and diurnal changes in ecdysteroid biosynthesis by prothoracic glands of rhodnius prolixus (hemiptera) in vitro during the last larval instar.the synthesis of ecdysteroids by prothoracic glands (pgs) of male last instar larvae of rhodnius prolixus was measured in vitro by radioimmunoassay throughout the course of larval-adult development. large and systematic changes in relative rates of synthesis occur during development. two bursts of elevated synthetic activity were found. the first commences as soon as development is initiated by a blood meal and lasts approximately 1 day. the second commences 4 days later and increases progressiv ...19892663631
pattern and composition of ionic currents around ovarioles of the hemipteran, rhodnius prolixus (stahl).two-dimensional vibrating probe analysis of extracellular currents around rhodnius prolixus ovarioles correlated with an earlier one-dimensional analysis but revealed asymmetrical circumferential current patterns and large tangential currents. na+, k+, and ca+2 have been tentatively identified as the major ions involved in these currents, with na+ being the major ion involved in current efflux.198929300571
the development of microtubular arrays in the germ tissue of an insect telotrophic ovary.the microtubular arrays characteristic of the trophic core and cords of the adult rhodnius prolixus ovary develop prior and during the larval--adult transformation. development of the microtubules was revealed by immunocytochemistry, electron microscopy and polyacrylamide electrophoresis and western blot analysis. microtubular arrays were first detected in the trophic cords and presumptive trophic core 6 days before the adult molt. cord microtubules increase in length and numbers as the trophic ...19892672416
biological characterization of a strain of trypanosoma cruzi chagas isolated from a human case of trypanosomiasis in california.in august 1982, the first autochthonous case of human american trypanosomiasis in california occurred. the isolate, the tuolumne strain of trypanosoma, was infective to young laboratory mice and capable of causing death or chronic disease in these animals. the morphology and mensural characteristics are described. this strain can develop in 2 species of triatominae native to california, triatoma protracta and t. rubida. the flagellates isolated from these insects were infective to vertebrate hos ...19892508500
in vitro cytotoxicity of rhodnius prolixus hemolytic factor and mellitin towards different trypanosomatids.trypanosoma cruzi strain y and clone dm28c and other trypanosomatids were exposed to two lytic agents, rhodnius prolixus hemolytic factor (rhf) and mellitin, in vitro. in both cases, the result was a significant decrease in the number of parasites after a 30-min treatment at 37 degrees c. rhf and mellitin had distinct activities on different strains and species of trypanosomatids. these observations suggest that rhf may be an important factor in selecting resistant strains of trypanosomes for de ...19892515905
action of activated 27,000 mr toxin from bacillus thuringiensis var. israelensis on malpighian tubules of the insect, rhodnius prolixus.the action of activated 27,000 mr toxin from bacillus thuringiensis var. israelensis (bti toxin) on malpighian tubules of rhodnius prolixus has been investigated. its binding to the tubules is slowed by low temperature but is not prevented even at 0 degree c. the binding is less effective at ph 10 than at ph7. pretreatment of the tubules with 0.1 mmol l-1 ouabain or bumetanide or 1 mumol l-1 5-hydroxytryptamine did not affect the toxicity of the toxin. the toxin causes very large changes in the ...19892632587
azadirachtin inhibits trypanosoma cruzi infection of its triatomine insect host, rhodnius prolixus. 19892657439
chagas' disease and its insect vector. effect of azadirachtin a on the interaction of a triatomine host (rhodnius prolixus) and its parasite (trypanosoma cruzi).the ed50 for moulting inhibition by injected azadirachtin a is for fourth instar larvae of all the triatomines, triatoma vitticepes, t. pseudomaculata, t. maculata, t. brasiliensis, t. lecticularis, t. matogrossensis, t. infestans, rhodnius prolixus. r. neglectus, r. robustus, panstrongylus megistus, and p. herrera in the range of 10-25 ng/larva. in rhodnius prolixus, the survival of t. cruzi was studied after treatment with the drug. if the trypomastigotes were fed in presence of 1.0 microgram ...19892663004
the effects of artificial diets on the anterior intestinal cell ultrastructure of rhodnius prolixus (hemiptera:reduviidae).mated female rhodnius prolixus were fed diets of washed rabbit erythrocytes (rbc), rabbit plasma, edestin (a plant storage protein) in ringer's or ringer's solution alone. all diets contained 1 mm atp. the effects of these diets on anterior intestinal cell ultrastructure were evaluated and compared to changes induced by normal blood feeding. separation of basal labyrinth membranes was induced earlier after ringer's-feeding than with all other diets. normal modifications of the rough endoplasmic ...19892668208
endpolyploidy and digestion in the midgut of rhodnius prolixus stål (hemiptera: reduviidae).the feulgen-dna content of the midgut cell nuclei of rhodnius prolixus is estimated by microspectrophotometry. midgut cells contain 23.35-32.16 pg dna/nucleus, which represents an increase of up to 26c when compared to diploid r. prolixus brain tissue. a high copy number cell population disappears from the anterior intestinal cells after feeding, and the presence of a new population of low copy number cells indicates that there may be some regeneration of the midgut epithelium in adult insects, ...19892688578
binding of lectins to culture and vector forms of trypanosoma rangeli tejera, 1920 (protozoa, kinetoplastida) and to structures of the vector gut.culture forms of trypanosoma rangeli could be agglutinated with canavalia ensiformis (con a) lectin and, less effectively with pisum sativum agglutinin (pea), at a concentration of 200 micrograms/ml. ricinus communis agglutinin i (rca i) agglutinated trypanosomes only if they were not previously washed with physiological ringer's solution. three other lectins did not react with the same parasite forms. direct or indirect lectin-gold labeling techniques were applied to lr-white embedded thin sect ...19892689636
trypanosoma (herpetosoma) leeuwenhoeki in choloepus hoffmanni and didelphis marsupialis of the pacific coast of colombia.trypanosoma (herpetosoma) leeuwenhoeki, originally described in panamanian sloths, was isolated from didelphis marsupialis (marsupialia) and choloepus hoffmanni (edentata) inhabiting the pacific coast of colombia. trypanosomes were characterized by their large blood forms (total length 51-53 microns), poor infectivity for mice, and lack of development in rhodnius prolixus. isoenzyme studies, with either strains or clones, revealed homogeneous profiles clearly distinct from trypanosoma cruzi and ...19892926591
trypanosoma (herpetosoma) rangeli tejera, 1920: study of the effects of the parasite on the vector.for evaluation of the possible pathogenicity of trypanosoma (herpetosoma) rangeli tejera, 1920 to the triatomid vector, first-stage nymphs of laboratory-bred insects were engorged upon albino mice showing average parasitemias of 2 x 10(6) and 2 x 10(5) trypanosomes/ml blood. the vector strains were: rhodnius prolixus ("new" strain), triatoma pallidipennis, and triatoma vitticeps. an "old" strain of r. prolixus (maintained 30 years in the laboratory) was also employed to check the effects of labo ...19892701258
developmental time and mortality in larvae of the reduviid bugs triatoma infestans and rhodnius prolixus after coprophagic infection with blastocrithidia triatomae (trypanosomatidae). 19883127477
morphometric analysis of rhodnius prolixus stal (hemiptera:reduviidae) midgut cells during blood digestion.post-feeding ultrastructural modifications to the midgut cells of rhodnius prolixus are quantified using morphometry. changes in relative and absolute volumes and/or surface areas are demonstrated for the whole cells, nuclei, mitochondria, rough endoplasmic reticulum, lysosomes, golgi apparatus, storage vesicles, glycogen, microvilli, and basal labyrinth, before and during blood digestion. these parameters are separately determined for cells from each of the three midgut regions, and are correla ...19883043761
[behavior of the infection and morphologic differentiation of trypanosoma cruzi and t. rangeli in the intestine of the vector rhodnius prolixus]. 19883070649
[feeding and defecation patterns in 5th instar nymphs of 4 species of triatomines (rhodnius prolixus, triatoma pallidipennis, t. infestans and t. brasiliensis, hemiptera, reduviidae)]. 19883071060
effects of precocene and azadirachtin on the development of trypanosoma cruzi in rhodnius prolixus. 19883075695
the initial stages in the action of an insecticidal delta-endotoxin of bacillus thuringiensis var. israelensis on the epithelial cells of the malpighian tubules of the insect, rhodnius prolixus.the effects of the 27 x 10(3) mr insecticidal delta-endotoxin from bacillus thuringiensis var. israelensis have been studied using, as a model system, isolated insect malpighian tubules. at all concentrations of the toxin higher than 1 microgram ml-1 (4 x 10(-8) moll-1) applied to the outer surface of the tubules, fluid secretion failed within about 30 min. except at very high concentrations, where failure always takes at least 30 s, there was an inverse relationship between the concentration of ...19883198707
a novel receptor capable of monitoring applied pressure in the abdomen of an insect.a pair of receptors, responding tonically to pressure applied internally, occurs on the ventral body wall of abdominal segments two to five in the adult of the blood-feeding insect, rhodnius prolixus. these receptors are located in a region of the body wall subject to forces directly related to the size and movement of the stomach, an enlarged region of the midgut which stores the blood meal, and are therefore well suited for monitoring the degree of distension there. the initiation of many endo ...198817820895
a relationship between the inhibition of heparan sulfate and chondroitin sulfate synthesis and the inhibition of molting by selenate in the hemipteran rhodnius prolixus.the insect rhodnius prolixus synthesizes heparan sulfate and chondroitin sulfate after a blood meal containing [35s]-inorganic sulfate. a 40 to 80% inhibition of heparan sulfate synthesis was obtained when the meal was supplemented with 10(-5) and 10(-4) m sodium selenate respectively. likewise an inhibition of the molting in the order of 30 to 60% was observed when the insects were fed with blood containing 10(-5) and 10(-4) m selenate respectively. the insects after a subsequent meal without s ...19872956948
the roles of haemolymphatic lipoproteins in the oogenesis of rhodnius prolixus.the fates of purified 32p-vitellin and 32p-lipophorin were followed in vitellogenic females of rhodnius prolixus. while the radioactivity from 32p-vitellin 6 hours after injection was found almost exclusively in the ovary, the radioactivity from injected 32p-lipophorin was found distributed among several organs. in the ovary, the radioactivity from 32p-vitellin was associated with the contents of the yolk granules. 32p-lipophorin delivered a great amount of radioactive phospholipids to the ovary ...19873334405
effects of precocene and azadirachtin in rhodnius prolixus: some data on development and reproduction.the results presented in this paper clearly indicate that precocene and azadirachtin are effective inhibitors of moulting and reproduction in the hemipteran rhodnius prolixus. the time of application is important and only applications of these substances early in the intermoulting period cause their effects in nymphs. the inhibition of moulting is fully reversed by ecdysone therapy. precocene and azadirachtin also affected drastically the oogenesis and egg deposition in this insect. precocene-in ...19873334403
inputs to the hormonal control of egg development in rhodnius prolixus.this paper re-examines existing data on the environmental inputs governing egg production in rhodnius prolixus. feeding has a direct effect on egg production such that the product of the unfed weight of the female times the weight of the blood meal is a good predictor of the number of eggs produced. mating modifies this input, so that mated females produce more eggs. egg production is governed by the corpus allatum, and indirect evidence suggests that the number of eggs producted by a female is ...19873334399
demonstration of a proallatotoxin-sensitive period in 4th-instar nymphs of rhodnius prolixus.1. topical application of the proallatotoxin ethoxyprecocene ii (60 micrograms/nymph) to 4th-instar nymphs of rhodnius prolixus at various times before and after a blood meal induced precocious metamorphosis. 2. the highest percentage of adultoids was obtained when proallatotoxin was applied prior to feeding or up to day 3 after the blood meal. 3. the proallatotoxin-sensitive period ended 4 days after feeding just before the maximum peak of ecdysteroid concentration in the hemolymph. 4. the sign ...19873318976
predation on rhodnius prolixus (hemiptera: reduviidae) by the spider theridion rufipes (araneida: theridiidae). 19873546692
lack of enzyme polymorphism in trypanosoma rangeli stocks from sylvatic and domiciliary transmission cycles in colombia.although trypanosoma rangeli is biologically and morphologically distinct from trypanosoma cruzi, these two hemoflagellates are epidemiologically linked. we report the results of enzyme electrophoretic studies of t. rangeli stocks isolated from sylvatic and domiciliary rhodnius prolixus, and infected humans inhabiting foci in which t. cruzi was sympatrically transmitted. t. rangeli stocks displayed electrophoretically detectable polymorphism for only a single enzyme, isocitrate dehydrogenase (ic ...19873812885
polymorphic organization of the endoplasmic reticulum of the malpighian tubule. evidence for a transcellular route.isosmotic fluid absorption carried out by many mammalian epithelia appears to be similar to the isosmotic secretion of insect epithelia such as the malpighian tubules, which are responsible for urine formation and osmoregulation. we have studied by electron microscopy (80 kv) the three-dimensional characteristics of organelles in the malpighian tubules of rhodnius prolixus using thick sections (0.3-0.5 microns) and uranyl and lead impregnation. the er presents a different organization in the upp ...19873079270
insect-borne and culture-derived metacyclic trypanosoma cruzi: differences in infectivity and virulence.we report in this paper significant differences in the virulence of insect-derived and cultured metacyclic forms of trypanosoma cruzi which are morphologically indistinguishable. mice infected intraperitoneally with 10(3) metacyclic t. cruzi isolated from rhodnius prolixus showed average parasitemia levels greater than 2 x 10(5) organisms/ml around day 10 post-infection (when first measured) and peak levels recorded on day 16 post-infection exceeded 4 x 10(7) organisms/ml. none of these animals ...19873107410
[method of biological control of triatominae, vectors of chagas disease, using entomopathogenic hyphomycetes. preliminary study].bioassays determined the pathogenic activity of 14 strains of 5 entomopathogenic hyphomycetous species (fungi imperfecti), beauveria bassiana, beauveria brongniartii, metarhizium anisopliae, nomuraea rileyi and paecilomyces fumosoroseus to rhodnius prolixus. treatments consisted of direct spraying with conidial titrated suspensions on first instar larvae. when tested at 3 x 10(5) conidia/cm2, only 2 strains, b. bassiana n. 297 and b. bassiana n. 326 killed 100% of larvae at 10 days post-exposure ...19873111731
density-dependent timing of defaecation by rhodnius prolixus, and its implications for the transmission of trypanosoma cruzi.transmission of trypanosoma cruzi is crucially dependent on the timing of defaecation by their insect vectors. experimental studies on rhodnius prolixus nymphs revealed a negative correlation between blood meal weight and defaecation time. bugs which fed to repletion defaecated on average 7 min after feeding, whereas bugs with interrupted feeds defaecated about 1 h later. as blood meal weight of triatomine bugs is density-dependent, these results suggest that the greatest risk of successful t. c ...19873113007
the permeability properties of septate junctions in malpighian tubules of rhodnius.this paper describes the structural characteristics and permeability properties of the smooth septate junctions between the upper malpighian tubule cells of a blood-sucking bug, rhodnius prolixus. the permeability of the paracellular route was tested only for solutes that could be demonstrated not to cross the epithelium via the cellular route. the intercellular clefts were readily permeated by sucrose, inulin and polyethylene glycol (peg), showing a higher permeability to molecules of smaller r ...19873320067
characterization of inducible lysozyme activity in the hemolymph of rhodnius prolixus.1. the characterization and partial purification of an induced lysozyme activity in the hemolymph of adult rhodnius prolixus inoculated with micrococcus lysodeikticus is described. 2. little or no activity against m. lysodeikticus appeared in the first hours after inoculation, but the activity increased reaching a maximum 4 days later, which was maintained to day 12. 3. the activity was characterized as lysozyme on the basis of the following considerations: 1) ph optimum and thermostability at a ...19873330677
studies on trypanosoma rangeli tejera, 1920. ix. course of infection in different stages of rhodnius prolixus.frequent individual observations od different stages of rhodnius prolixus exposed to trypanosoma rangeli, revealed a higher susceptibility to infection in the bugs exposed during the two first instars. the mortality rate in infected bugs was significantly higher than in controls, indicating that the parasite was responsible for the majority of deaths. an analysis of the mortality distribution, per instar, is presented. statistical analysis of deaths among the different infected instars, showed t ...19873333807
histochemical studies of uric acid in some insects. 3. excretion of uric acid by the malpighian tubules in calliphora vicina and rhodnius prolixus.in adult calliphora uric acid is excreted throughout the malpighian tubules. histochemical preparations for the light microscope show uric acid passing through the cells and forming crystalline spheres in immediate contact with the microvilli. uric acid appears to be synthesized and discharged into the haemolymph by the fat body cells. in rhodnius there is no visible uric acid in the cells or lumen of the upper segment of the tubule (two-thirds of the total length of the tubule) apart from occas ...198718620198
chemical structure, juvenile hormone activity and persistence within the insect of juvenile hormone mimics for rhodnius prolixus. 1986323368
rhodnius neivai: a new experimental vector of trypanosoma rangeli.rhodnius neivai was as efficient as rhodnius prolixus and rhodnius robustus in transmitting by bite a colombian strain of trypanosoma rangeli following its inoculation into the hemocoel. under conditions of the study the strain of t. rangeli had a high and constant infectivity to the salivary glands of r. prolixus, its natural vector in colombia. six species of triatoma and dipetalogaster maximus likewise inoculated did not develop metatrypomastigotes in the salivary glands. of the 12 known spec ...19863518505
excretion of trypanosoma cruzi by various stages of rhodnius prolixus. 19863528006
species-specific allergens from the salivary glands of triatominae (heteroptera:reduviidae).we investigated allergenic cross-reactivity among species of the blood-feeding insects of the subfamily triatominae. by skin testing, patients allergic to either triatoma protracta or t. rubida gave positive responses only to the respective salivary antigen. rast-inhibition experiments demonstrated that binding of ige antibodies to t. protracta antigen was not inhibited by salivary extracts from t. rubida, t. cavernicola, t. rubrofasciata, or rhodnius prolixus. the same level of species specific ...19863531291
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