| 1. inheritance of the ability to transmit t. cruzi in rhodnius prolixus. 2. natural and acquired inhibitory factors in animal sera against t. cruzi in culture. 3. ability of all immature and mature stages of rhodnius prolixus to infection with t. cruzi. | | 1973 | 4591209 |
| rhodnius prolixus: inheritance of the ability to transmit schizotrypanum cruzi. | | 1973 | 4593648 |
| transmission of trypanosoma cruzi by rhodnius prolixus. | | 1973 | 4593649 |
| trypanosome density in the rectum of rhodnius prolixus infected with t. cruzi. | | 1973 | 4594459 |
| [the cycle of intestinal protease activity in larval and adult rhodnius prolixus (hemiptera, reduviidae)]. | | 1973 | 4612636 |
| [sterilization of rhodnius prolixus stal, by metepa (tris (1-(2 methyl) aziridinil phosphoric oxide) and its action of trypanosoma cruzi]. | | 1972 | 4615357 |
| the effect of abnormal human hemoglobin (hbs) on the blood meal size of the hematophagous bug rhodnius prolixus. | | 1974 | 4617277 |
| [a laboratory experiment with the chemosterilant hempa in rhodnius prolixus]. | | 1972 | 4632845 |
| laboratory studies of trypanosoma cruzi infections in: rhodnius prolixus--larvae and adults in: triatoma infestans, t. protracta and t. maculata--adults. | | 1967 | 4861087 |
| some observations on xenodiagnosis with rhodnius prolixus and triatoma infestans in human infections with bahian strains of trypanosoma cruzi. | | 1969 | 4980623 |
| natural infections and behavior of trypanosoma rangeli and trypanosoma cruzi in the vector rhodnius prolixus in colombia. | | 1969 | 4980776 |
| histology of rhodnius prolixus infected with trypanosoma rangeli. | | 1971 | 4997588 |
| the uptake of trypanosoma cruzi by rhodnius prolixus and its later excretion. | | 1969 | 5368019 |
| observations on the development of trypanosoma rangeli in the hemocoel of rhodnius prolixus. | | 1970 | 5442845 |
| trypanosoma rangeli: effect on excretion in rhodnius prolixus. | | 1971 | 5558074 |
| the use of artificial diets to determine some of the effects of nocardia rhodnii on the development of rhodnius prolixus. | | 1968 | 5649234 |
| pathogenicity of trypanosoma rangeli for rhodnius prolixus stal in nature (hemiptera: reduviidae) (kinetoplastida: trypanosomatidae). | | 1968 | 5699971 |
| mechanical transmission of trypanosoma lewisi (kinetoplastida: trypanosomidae) by rhodnius prolixus (hemiptera: reduviidae). | | 1968 | 5699976 |
| experimental infection of triatoma infestans and rhodnius prolixus with trypanosomatidae of the genera crithidia and blastocrithidia. | | 1968 | 5703437 |
| the effect of nutrient intake on the development and the egg production of rhodnius prolixus ståhl (hemiptera: reduviidae). | | 1965 | 5838417 |
| biological factors influencing transmission of trypanosoma rangeli by rhodnius prolixus. | | 1965 | 5857287 |
| ultrastructure of trypanosoma cruzi in the rectum of rhodnius prolixus. | | 1966 | 5960783 |
| effects of sublethal dose exposure to dieldrin on rhodnius prolixus (hemiptera: reduviidae) under laboratory conditions. | the effects of a sublethal dose of dieldrin (7.2 x 10(-5) g/day) were evaluated on oxygen consumption, survivorship, moulting and reproduction of rhodnius prolixus. no difference was found in oxygen consumption between treated and control male insect. survivorship proved to be very much affected by the sublethal exposure, but this was strongly dependent on the feeding stage of the individuals. moulting times were prolonged by 2 to 3 days depending on the instar, but the number of individuals tha ... | 1980 | 6104425 |
| experimental infections in venezuelan lizards by trypanosoma cruzi. | virulent trypomastigotes of the y strain of trypanosoma cruzi were administered to tropidurus hispidus, ameiva ameiva, cnemidophorus lemniscatus, polychrus marmoratus, and phyllodactylus ventralis (sauria). intraperitoneal and subcutaneous inoculations of lizards with mouse blood or with feces of infected rhodnius prolixus (reduviidae, triatominae), as well as forced ingestion of triturated rhodnius, produced no parasitaemias detectable either directly or by xenodiagnosis, while control mice bec ... | 1981 | 6115559 |
| cross-reactivity of vector-borne metacyclic forms of trypanosoma cruzi with mammalian and culture stages. | metacyclic forms of trypanosoma cruzi isolated from the hindgut of infected insect vectors (rhodnius prolixus) were found to be immunologically cross-reactive with cultured epimastigote, amastigote, and metacyclic stages of the parasite as well as with bloodstream trypomastigote forms by direct agglutination and indirect immunofluorescence techniques. sera specific for each of these forms of the parasite systematically yielded maximal antibody titers when measured against the homologous antigen, ... | 1983 | 6195335 |
| functional design of microvilli in the malpighian tubules of the insect rhodnius prolixus. | the malpighian tubules of rhodnius prolixus are divided into two regions; the upper tubule, which is the site of isosmotic secretion and haemolymph filtration, and the lower tubule where water and kcl are resorbed. in the upper tubule the microvilli are arranged in clumps consisting of several hundred microvilli lying closely parallel. the microvillar plasma membranes do not touch but are held approximately equal to 16 nm apart along the full length of the microvilli. as a consequence, the extra ... | 1983 | 6348047 |
| crystallized hemoglobin in rhodnius prolixus after a blood meal on guinea-pig. | several blood-sucking arthropods, after a blood meal, are able to store the hemoglobin from their hosts in a crystalline state in their digestive system. guinea-pig hemoglobin crystallizes in the stomach of the reduviid bug rhodnius prolixus in two different crystal types. we show them to be crystallographically identical and to contain the same liganded state of hemoglobin, i.e. they represent different habits of the same crystal modification. the hemoglobin crystallizes in oxy-form and ages in ... | 1983 | 6360705 |
| secretion by the malpighian tubules of rhodnius prolixus stal: electrical events. | transepithelial and intracellular potentials have been simultaneously recorded from rhodnius upper malpighian tubules before and after stimulation of fluid secretion. the transepithelial electrical response to the diuretic hormone mimic 5-hydroxytryptamine (5-ht) was triphasic; recordings of intracellular potential changes indicated that the three phases represented successive events at the apical membrane. depolarizations produced by increasing the bathing medium potassium concentration indicat ... | 1984 | 6379094 |
| effects of juvenile hormone analogue on ecdysis prevention induced by precocene in rhodnius prolixus (hemiptera:reduviidae). | precocene ii, added to the meal of fourth-instar larvae of rhodnius prolixus (25 micrograms/ml of blood), induced an increase in the duration of the molting cycle. this effect was related to the decrease of both the nuclear area of the prothoracic gland cells and the mitotic activity in epidermal cells. juvenile hormone analogue applied topically (60 micrograms/insect) together with precocene ii treatment avoided atrophy of the prothoracic glands and induced a higher number of epidermal mitosis ... | 1984 | 6398393 |
| studies on trypanosoma rangeli tejera, 1920. vii--its effect on the survival of infected triatomine bugs. | the pathological effects of trypanosoma rangeli on rhodnius prolixus and r. robustus, and the relation of mortality to infection, were studied under laboratory conditions. frequent observations revealed that when the first instar nymphs of r. prolixus and r. robustus were infected with t. rangeli, survival of the bugs during the stages of development to the adult stage decreased. this decrease was statistically significant when compared with uninfected control-bugs, indicating that t. rangeli is ... | 1984 | 6399091 |
| studies on trypanosoma rangeli tejera, 1920. vi. developmental pattern in the haemolymph of rhodnius prolixus. | the morphological sequence of trypanosoma rangeli development in the body cavity of rhodnius prolixus is described. the metacyclic trypanosome is the product of successive division and transformation during the intra and extracellular development in the haemocoele. the significance of the early invasion of t. rangeli into the haemolymph is discussed. the epidemiological importance of the developmental pattern of t. rangeli in the vectors haemolymph and the host-response to the parasite are consi ... | 1983 | 6400168 |
| susceptibility of insect-borne, metacyclic forms of trypanosoma cruzi to antibody-mediated mechanisms of destruction. | the effect of passive antibody transfer against infection with vector-borne, metacylic forms of trypanosoma cruzi, and possible mechanisms of immunologic lysis of these organisms, were examined in this work. anti-t. cruzi antibodies from mice surviving an infection conferred marked protection against challenge with a lethal dose (2,000 organisms) of metacyclic flagellates isolated from the reduviid insect rhodnius prolixus. in vitro lysis of these parasites by immune sera from mice or chronic ch ... | 1983 | 6418013 |
| passage of solutes through walls of malpighian tubules of rhodnius by paracellular and transcellular routes. | the walls of isolated upper malpighian tubules of the insect, rhodnius prolixus, are much more permeable to small relatively unchanged solutes (ethanol, xylose, and mannitol) than to larger or more charged solutes (acetate, glycine, tyrosine, and inulin). the more permeable solutes rapidly reach concentrations in the tubule cells equivalent to their concentrations in the bathing medium; the less permeable solutes do not penetrate into the cells. the time course of accumulation of permeable solut ... | 1984 | 6426328 |
| epidemiology of trypanosoma cruzi in the oriental plains of colombia. | epidemiologic studies to define the domiciliary and extradomiciliary transmission cycles of trypanosoma cruzi and trypanosoma rangeli in the oriental plains of colombia were conducted in the gallery forests near carimagua and el porvenir. one-hundred and seven palm trees belonging to nine genera were examined; triatomines were found in only three palm species, the leaves of which are locally used for roof thatching: 2/29 maximiliana elegans, 1/7 mauritia flexuosa and 7/7 scheelea sp. bugs were a ... | 1984 | 6439062 |
| [finding of rhodnius prolixus stal, 1859, in babassu palm trees]. | | 1984 | 6443714 |
| dissociation of insect malpighian tubules into single, viable cells. | the malpighian tubules of insects are generally composed of more than one cell type. in the hemipteran rhodnius prolixus, the tubules are divided into two regions, termed the upper and lower tubules, each of which is composed of a distinct cell type. in the dipteran aedes taeniorhynchus, primary and stellate cells are interspersed throughout the length of the tubules. we report here techniques for the dissociation of the malpighian tubules of both of these species into single cells. tubules are ... | 1984 | 6533146 |
| studies on trypanosomes in the taiwan monkey. | fifty-three or 9% of 594 taiwan monkeys, macaca cyclopis, were found infected with a trypanosome species. the parasites were recovered from monkey blood in diaphasic blood-agar culture medium with a locke's solution overlay. trypanosomes were found on only a few thick blood smears and no dividing or multiplying forms were found. some of the organisms had a free-flagellum (4.7 microns), an undulating membrane and both ends of the body were pointed. the total length averaged 41.7 microns; nucleus ... | 1983 | 6673131 |
| description of new fibrinolytic enzyme, isolated from the haemolymph of rhodnius prolixus stal (heteroptera reduviidae). | a new fibrinolytic enzyme, isolated from the haemolymph of rhodnius prolixus stal (heteroptera, reduviidae) has been discovered. this enzyme does not act by activating plasminogen to plasmin. however, the split products obtained with this new enzyme inhibit fibrin formation in normal plasma. this enzyme seems to act specifically on the proteins involved in blood coagulation. its origin has induced us to name it prolixase. | 1982 | 6762857 |
| [feeding preferences in 3 species of triatominae (hemiptera: reduviidae) in experimental conditions]. | feeding preferences of three species of triatomines (triatoma infestans, t. dimidiata, and rhodnius prolixus) on four vertebrate hosts (opposum, dog, chicken and toad) were studied in a specially designed cage during daylight (2 hours) and at night (14 hours). t. infestans and r. prolixus remained close to the host after feeding, while t. dimidiata wandered a short distance away, apparently for protection against preying by the host. r. prolixus showed the lightest values of ingestion in relatio ... | 1982 | 6763728 |
| [rhodnius prolixus stal, 1859, in goiás, brazil. preliminary report]. | | 1982 | 6764950 |
| the effect of lampit on trypanosoma rangeli in experimentally infected mice. | mice experimentally inoculated with metacyclic forms of trypanosoma rangeli were given orally 10, 25, 50 or 100 mg/kg of body weight/day of lampit on 20 consecutive days. the results of combined examinations of fresh blood, giemsa stained blood preparations, blood cultures, blood concentration, repeated xenodiagnosis with rhodnius prolixus and blind passages via triatomine bites to other mice demonstrated that a dose of 50 to 100 mg/kg/day of the drug eliminated t. rangeli from the blood of all ... | 1982 | 6814024 |
| the activity of nifluridide on reduviids and rodent and human trypanosomes. | the ability of nifluridide to kill reduviids was assayed in mice fed 7 ppm in diet and on cattle injected subcutaneously at 5 mg/kg body weight. nifluridide was systemically active against triatoma infestans on mice and rhodnius prolixus on cattle. no effects on trypanosoma (schizotrypanum) cruzi could be detected in the intestinal contents of triatoma infestans killed by the compound. in vitro and in vivo studies were conducted to determine the effects of nifluridide on trypanosomes growing in ... | 1982 | 6815915 |
| developmental stages of trypanosoma cruzi-like flagellates in cavernicola pilosa. | the developmental stages of trypanosoma cruzi ssp., found in the intestinal tract of cavernicola pilosa, are described and measurements given for nine life stages. the frequencies of the various stages in foregut, midgut and hindgut of the triatomines are provided; parasites were rare in the foregut and metatrypomastigotes were seen only in the mid- and hindguts. all adult bugs examined harboured intestinal infections of t. cruzi-like flagellates, large clumps of amastigotes were frequently obse ... | 1982 | 6820697 |
| diuresis from stimulation of left atrial receptors in dogs: further purification of the causative agent from plasma. | stimulation of atrial receptors by distension of a balloon in the left atrium of anaesthetized dogs results in a reflex diuresis mediated by an unknown humoral agent. this paper reports the further purification from plasma of acetone extracts of the humoral agent which may mediate the diuretic response. activity of the humoral agent was detected using the malpighian tubules of rhodnius prolixus. gel filtration of the acetone extracts on sephadex g-25 and g-100, followed by dialysis of the fracti ... | 1983 | 6856747 |
| abolition of atrial receptor diuresis and of release of humoral agent by cooling the vagal nerves. | stimulation of atrial receptors in anaesthetized dogs results in a reflex increase in urine flow mediated by vagal myelinated fibres and, in part, by a humoral agent of unknown identity. the humoral agent has been detected by an in vitro preparation of the malpighian tubules of rhodnius prolixus. the purpose of this investigation was to determine whether the present extract of plasma purporting to contain the humoral agent is also related to the reflex diuresis. in nine chloralose anaesthetized ... | 1983 | 6856748 |
| diuresis from stimulation of left atrial receptors: adh and the malpighian tubules of rhodnius prolixus. | stimulation of left atrial receptors causes a diuresis partly through a blood borne agent. malpighian tubules of rhodnius prolixus can detect a blood borne agent during the diuresis. it has been suggested that the agent is adh but this is in dispute. in the present investigation, vasopressin (1-300 mu i.u. cm-3) was found to have no effect on malpighian tubule secretion when added to plasma, rhodnius ringer and rhodnius ringer + 5-ht. in addition, it was shown that incubation with sodium thiogly ... | 1981 | 6910734 |
| the penetration of the salivary glands of rhodnius prolixus by trypanosoma rangeli. | ultrastructural studies of the mechanism of penetration of the salivary gland of the reduviid bug rhodnius prolixus by trypanosoma rangeli showed that trypanosomes from the haemocoele penetrate the outer "membranes" of the gland flagellum foremost, disrupting the inner layers, to pass between the muscle cells to reach the gland cell basement membrane. this latter is also penetrated flagellum foremost, the parasite invaginating the gland cell plasmalemma beneath, to create a vacuole in which the ... | 1980 | 6994382 |
| [resistance to fast in venezuelan triatomidae (hemiptera, reduviidae). i- rhodnius prolixus stal]. | | 1980 | 7001606 |
| early invasion of trypanosoma rangeli into the haemolymph of rhodnius prolixus. | | 1980 | 7001694 |
| role of angiotensin ii and bradykinin in the diuresis caused by stimulation of atrial receptors. | the diuretic response to stimulation of left atrial receptors, by distending balloons located either at the pulmonary vein-left atrial junctions or in the body of the left atrium, was studied during blockade of the generation of angiotensin ii using a continuous infusion of angiotensin converting enzyme inhibitor, sq 14,225, in anaesthetized dogs. despite blockade of angiotensin conversion, known also to potentiate the activity of bradykinin, a diuretic response was obtained in each dog; the res ... | 1980 | 7005924 |
| lectins of distinct specificity in rhodnius prolixus interact selectively with trypanosoma cruzi. | lectins of different activities were found in the crop, midgut, and hemolymph of the insect rhodnius prolixus. these were not specific for n-acetyl-d-mannosamine, alpha-n-acetyl-d-galactosamine, and alpha- and beta-galactose, respectively. lectin receptors were detectable in epimastigote but not in trypomastigote forms of trypanosoma cruzi, a protozoan parasite of the insect and of humans. | 1981 | 7006082 |
| [ultrastructure of the antennal sensillae of the bug, rhodnius prolixus (hemiptera, reduviidae)]. | on the antenna of the bug r. prolixus we found numerous receptors which can be classified into three categories: mechanoreceptors (sensilla chaetica), olfactory (sensillae trichodea, basiconica and caeloconica) and gustatory (sensilla trichodea) receptors. the number, size and distribution on the antenna of each type have been recorded. a description of each of these sense organs is given. tactile hairs are present on all of the antennal segments while thin-walled chemoreceptors are limited to s ... | 1980 | 7007992 |
| detection of trypanosoma rangeli by salivation of infected rhodnius prolixus on glass slides. | | 1980 | 7008724 |
| trypanosoma cruzi development is independent of protein digestion in the gut of rhodnius prolixus. | | 1980 | 7012289 |
| an energy budget for rhodnius prolixus (hemiptera: reduviidae) under laboratory conditions. | | 1981 | 7021833 |
| 5-hydroxytryptamine-stimulated mitochondrial movement and microvillar growth in the lower malpighian tubule of the insect, rhodnius prolixus. | rapid initiation of ion transport occurs in the lower malpighian tubule of the insect rhodnius prolixus following feeding in vivo or stimulation with 5-hydroxytryptamine (5-ht) in vitro. using the electron microscope, we have conducted a morphometric analysis of cells in the lowest one-third of the lower tubule, demonstrating that 5-ht also induces mitochondrial movement and microvillar growth simultaneously with, but independent of, the onset of ion transport. mitochondria move from a position ... | 1981 | 7031069 |
| the effects of precocene ii on reproduction and development of triatomine bugs (reduviidae: triatominae). | precocene ii is a botanically derived chemical that inhibits the production of juvenile hormone (jh) in insects. the effects of this anti-jh compound on molting and growth by rhodnius prolixus and triatoma dimidiata and reproduction in r. prolixus were tested and the efficacy of precocene ii as a fumigant was assessed. precocene ii induced precocious metamorphosis in both species when applied by either contact exposure or fumigation, and this effect could be prevented by juvenile hormone replace ... | 1982 | 7041667 |
| infectivity of trypanosoma rangeli in a promonocytic mammalian cell line. | the existence of an intracellular stage of trypanosoma rangeli in the vertebrate host was evaluated by experimental infection of the u937 histiocytic cell line with the san agustín strain and the ub66-5b clone. the identity of the parasites at the beginning and end of the experiments was confirmed through biological behavior in the vector and mammal hosts, isoenzymes, polymerase chain reaction (pcr), and monoclonal antibodies. infectivity to u937 cells of t. rangeli obtained from culture and sal ... | 1995 | 7472856 |
| two heads are better than one: crystal structure of the insect derived double domain kazal inhibitor rhodniin in complex with thrombin. | rhodniin is a highly specific inhibitor of thrombin isolated from the assassin bug rhodnius prolixus. the 2.6 angstrum crystal structure of the non-covalent complex between recombinant rhodniin and bovine alpha-thrombin reveals that the two kazal-type domains of rhodniin bind to different sites of thrombin. the amino-terminal domain binds in a substrate-like manner to the narrow active-site cleft of thrombin; the imidazole group of the p1 his residue extends into the s1 pocket to form favourable ... | 1995 | 7489704 |
| 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 ... | 1995 | 7498422 |
| 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 ... | 1995 | 7614667 |
| 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- ... | 1995 | 7658188 |
| 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 ... | 1993 | 7689981 |
| 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 ... | 1995 | 7738030 |
| 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 ... | 1995 | 7745280 |
| 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 ... | 1994 | 7885254 |
| 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 ... | 1994 | 7888081 |
| 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 ... | 1994 | 7964498 |
| 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 ... | 1994 | 8049688 |
| 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 ... | 1994 | 8073413 |
| 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 ... | 1994 | 8080655 |
| 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 ... | 1994 | 8162960 |
| [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 ... | 1993 | 8209115 |
| 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 ... | 1993 | 8257239 |
| 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 ... | 1993 | 8344906 |
| 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 ... | 1995 | 8544739 |
| differential in vitro and in vivo behavior of three strains of trypanosoma cruzi in the gut and hemolymph of rhodnius prolixus. | a comparison was made of the agglutination and lysis of three strains of trypanosoma cruzi in gut extracts and hemolymph of rhodnius prolixus and the results obtained were correlated with the success or failure of the parasite strain to infect the digestive tube or to survive in the hemocel after inoculation. both t. cruzi strains dm28c and cl urine 35 days after feeding with parasites. concomitantly, both of these strains were agglutinated but not lysed by the crop extracts. in contrast, t. cru ... | 1996 | 8617337 |
| crystallographic evidence that the f2 kringle catalytic domain linker of prothrombin does not cover the fibrinogen recognition exosite. | the 2.6-a x-ray crystal structure of bovine alpha-thrombin in complex with rhodniin, a protein inhibitor isolated from the bug rhodnius prolixus, has been solved and refined. the structure has enabled us to trace the n-terminal part of the 49-residue a-chain of bovine alpha-thrombin for the first time, which is fixed in a u-shaped loop on the molecular surface opposite the active site canyon. model building shows that the 25 amino acid residues that link the a-chain and f2 kringle cannot run thr ... | 1996 | 8631941 |
| trypanosoma cruzi and erythrocyte agglutinins: a comparative study of occurrence and properties in the gut and hemolymph of rhodnius prolixus. | the activity of agglutinins found in the gut tissues and hemolymph of rhodnius prolixus was tested using rabbit erythrocytes, trypanosoma cruzi, or trypanosoma rangeli as test particles. in addition, investigations were made of the influence of parasitic infection and insect diet on the agglutination titers. a range of physicochemical tests and carbohydrate-binding studies were performed and inhibitors were subsequently found for both the crop agglutinin (p-nitrophenol-derived sugars) and the he ... | 1996 | 8654555 |
| lignanes from the brazilian melia azedarach, and their activity in rhodnius prolixus (hemiptera, reduviidae). | a study of the phagoinhibitor and anti-moulting activities of the brazilian melia azedarach, collected in the state of rio de janeiro, brazil, allowed the isolation of four lignanes identified as pinoresinol (1), bis-epi-pinoresinol (2), the hemicetal (3) and the diacid (4). these substances are devoid of anti-moulting activity. | 1995 | 8731373 |
| thrombin inhibitors of bloodsucking animals. | hematophagous animals have the unique ability to inhibit blood coagulation when sucking blood from a wound. this article concerns thrombin inhibitors from these animals, specifically the one from the insect rhodnius prolixus. to date, the most-studied inhibitor from these animals is hirudin, which specifically neutralizes thrombin but no other clotting serine proteases. the biochemical properties of hirudin are described. hirudinlike thrombin inhibitors from the asian leech hirudo manillensis, h ... | 1996 | 8807718 |
| [use of new tools for controlling triatomines in different entomologic situations in the american continent]. | the field results of new tools for triatomine control developed under the sponsorship of who/tdr are reported: a) a slow-release "paint" containing malathion; b) fumigant cans containing cypermethrin and ddvp, and c) sensor boxes for the detection of triatomine infestations. field assays were performed in chile, honduras and paraguay against triatoma infestans, t. dimidiata and rhodnius prolixus, accordingly to a standard protocol designed by a who experts committee. preliminary 6 months post-tr ... | 1996 | 9026830 |
| effect of azadirachtin a on the fine structure of the midgut of rhodnius prolixus. | rhodnius prolixus fed with azadirachtin a showed significant changes in the ultrastructural organization of the epithelial cells of the stomach and the intestine. changes included (a) clustering of the microvilli, (b) disorganization of the extracellular membrane layers, (c) modifications in the array of spherocytes, and (d) disorganization of the basal portion of the epithelial cells. we suggest that these changes interfere significantly with the intestinal environment, making it unsuitable for ... | 1997 | 9028929 |
| prevention of insect-borne disease: an approach using transgenic symbiotic bacteria. | expression of molecules with antiparasitic activity by genetically transformed symbiotic bacteria of disease-transmitting insects may serve as a powerful approach to control certain arthropod-borne diseases. the endosymbiont of the chagas disease vector, rhodnius prolixus, has been transformed to express cecropin a, a peptide lethal to the parasite, trypanosoma cruzi. in insects carrying the transformed bacteria, cecropin a expression results in elimination or reduction in number of t. cruzi. a ... | 1997 | 9096383 |
| nitric oxide binding and crystallization of recombinant nitrophorin i, a nitric oxide transport protein from the blood-sucking bug rhodnius prolixus. | a nitric oxide transport protein (nitrophorin i) from the salivary glands of the blood-sucking bug rhodnius prolixus has been expressed as an insoluble form in escherichia coli, reconstituted with heme, and characterized with respect to no binding kinetics and equilibria. no binding and absorption spectra for recombinant nitrophorin i were indistinguishable from those of the insect-derived protein. the degree of no binding, the rate of no release, and the soret absorption maxima for nitrophorin ... | 1997 | 9109649 |
| biological effects of canatoxin in different insect models: evidence for a proteolytic activation of the toxin by insect cathepsinlike enzymes. | canatoxin is a toxic protein isolated from the jackbean, canavalia ensiformis. the toxin injected intraperitoneally is lethal for mice and rats; however, it is inactive if given orally. in this study, manduca sexta (l.) (lepidoptera), schistocerca americana (drury) (orthoptera), drosophila melanogaster (l.) (diptera), aedes aegypti (l.) (diptera), rhodnius prolixus (stål) (hemiptera), and callosobruchus maculatus (f.) (coleoptera) were fed on canatoxin-containing diets. no effects were seen in m ... | 1997 | 9145031 |
| lipophorin density variation during oogenesis on rhodnius prolixus. | the density of lipophorin was determined in adult females of rhodnius prolixus on different days after a meal. several populations od lipoproteins, differing in density but always in the range of hdl, were found in the hemolymph. the density of the major population was analyzed and a complex profile of density variation was found associated with the principal metabolic events in these insects digestion and oogenesis. during the initial three days after the blood meal, with the onset of the diges ... | 1997 | 9177134 |
| biomorphological alterations induced by an anti-juvenile hormonal compound, 2-(2-ethoxyethoxy)ethyl furfuryl ether, on three species of triatominae larvae (hemiptera, reduviidae). | applied topically to larvae of rhodnius prolixus stal, triatoma infestans (klug) and panstrongylus herreri wygodzinsky, vectors of trypanosoma cruzi, the causative agent of chagas' disease, a synthetic, furan-containing anti-juvenile hormonal compound, 2-(2-ethoxyethoxy)ethyl furfuryl ether induced a variety of biomorphological alterations, including precocious metamorphosis into small adultoids with adult abdominal cuticle, ocelli, as well as rudimentary adultoid wings. some adultoids died duri ... | 1997 | 9332589 |
| expression, reconstitution and characterization of prolixin-s as a vasodilator--a salivary gland nitric-oxide-binding hemoprotein of rhodnius prolixus. | prolixin-s, an anticoagulant from the salivary gland of the blood-sucking insect rhodnius prolixus is also one of the members of salivary gland hemoproteins. we produced recombinant protein using a baculovirus-insect cell expression system, reconstituted the hemoprotein and made some characterization of it as a nitric oxide carrier. the reconstituted protein exhibited the absorption spectrum of a high-spin ferric hemoprotein with a soret absorption peak at 400 nm. by binding nitric oxide (no-pro ... | 1997 | 9363788 |
| [wild vectors of chagas' disease in an urban area of manaus (am): flying activity during dry and rainy seasons]. | adults of rhodnius prolixus, r. pictipes and panstrongylus geniculatus found in houses in manaus have high rates of trypanosoma cruzi infection. rhodnius spp. were found throughout the year, but males of p. geniculatus were significantly more frequent in the dry season. | 1998 | 9477705 |
| random amplification of polymorphic dna as a tool for taxonomic studies of triatomine bugs (hemiptera: reduviidae). | eleven of 27 decameric primers were found to be suitable for random amplification of polymorphic dna (rapd) from triatomine bugs on the basis that they produced discrete profiles and distinguished among panstrongylus megistus (burmeister), rhodnius prolixus stål, and triatoma infestans (klug). the legs, or single leg segments, of individual bugs were used as the source of dna so that the taxonomic value of the bug was conserved. within the scope of the specimens studied, rapd profiles allowed as ... | 1998 | 9542343 |
| synanthropic rodent reservoirs of trypanosoma (schizotrypanum) cruzi in the valley of caracas, venezuela. | direct blood examination and xenodiagnosis of 47 synanthropic rodents (rattus rattus, r. norvegicus, mus musculus) captured in the valley of caracas, venezuela, revealed trypanosomal infections in 12 r. rattus, 10 with t. lewisi and 2 with t. cruzi. of the latter the course of parasitemia, the pleomorphism of the bloodstream trypomastigotes, tissue in naturally and experimentally infected rats and mice, host mortality, morphology of fecal parasites in rhodnius prolixus used for xenodiagnosis, an ... | 1997 | 9661306 |
| nitrophorin-2: a novel mixed-type reversible specific inhibitor of the intrinsic factor-x activating complex. | nitrophorin-2 (np-2), isolated from salivary glands of the blood-sucking insect rhodnius prolixus, has been shown to be a specific inhibitor of the intrinsic factor x-(fx)-activating complex. the inhibitory effect of np-2 is most potent in the presence of both fviiia and phospholipids (artificial phospholipid vesicles or activated human platelets). detailed kinetic analyses of the inhibitory mechanism of np-2 demonstrated a decrease in both vmax and k(m) of activated fix-(fixa)-catalyzed fx acti ... | 1998 | 9692958 |
| the occurrence of rhodnius prolixus stal, 1859, naturally infected by trypanosoma cruzi in the state of rio de janerio, brazil (hemiptera, reduviidae, triatominae). | | 1998 | 9698882 |
| factors affecting conidial production of beauveria bassiana from fungus-killed cadavers of rhodnius prolixus. | the epizootic potential of beauveria bassiana for control of the triatomine vectors of chagas' disease was investigated by studying the effects of both biotic and abiotic factors on the recycling of a highly virulent fungal isolate from fungus-killed cadavers of rhodnius prolixus. the conidial production of b. bassiana from mummified cadavers of r. prolixus required high rh levels of at least 96.5% rh. at 97% rh and 25 degrees c, the amount of conidia per insect ranged from 5.3 x 10(6) (on first ... | 1998 | 9709008 |
| purification and cloning of the salivary nitrophorin from the hemipteran cimex lectularius. | cimex lectularius and rhodnius prolixus contain salivary nitric oxide (no) that may help them to feed on their vertebrate hosts by promoting vasodilation and inhibiting platelet aggregation. salivary no is associated with heme proteins (nitrophorins) that store and transport no from the insect salivary glands to the skin of the host. in this study, the salivary nitrophorin of cimex lectularius was purified by deae chromatography and reverse-phase high-performance liquid chromatography. the purif ... | 1998 | 9716517 |
| the crystal structure of nitrophorin 4 at 1.5 a resolution: transport of nitric oxide by a lipocalin-based heme protein. | nitrophorins are nitric oxide (no) transport proteins from the saliva of blood-feeding insects, which act as vasodilators and anti-platelet agents. rhodnius prolixus, an insect that carries the trypanosome that causes chagas' disease, releases four no-loaded nitrophorins during blood feeding, whereupon the ligand is released into the bloodstream or surrounding tissue of the host. histamine, a signaling molecule released by the host upon tissue damage, is tightly bound by the nitrophorins; this m ... | 1998 | 9782054 |
| beauveria bassiana (hyphomycetes) as a possible agent for biological control of chagas disease vectors. | beauveria bassiana (balsamo) vuillemin (isolate cg306) was tested on 3rd instars of 9 triatoma spp., 4 rhodnius spp., 2 panstrongylus spp. and dipetalogaster maxima (uhler) at 25 degrees c and 50% rh. quantitative sporulation of the fungus on cadavers was studied at 25 degrees c and 97% rh. mortality, estimates of survival time, and conidial production on cadavers differed significantly among the genera and species tested. panstrongylus herreri wygodzinsky, dipetalogaster maxima, triatoma pictur ... | 1998 | 9835689 |
| salivary heme proteins distinguish rhodnius prolixus from rhodnius robustus (hemiptera: reduviidae: triatominae). | rhodnius prolixus interpopulation variability was studied based on a new approach using salivary heme proteins (nitrophorins) electrophoresis in starch gel. we compared salivary proteins profiles of r. prolixus from three different laboratory colonies from honduras, venezuela, brazil and rhodnius robustus from venezuela, constructing a upgma. the honduran and venezuelan populations could not be distinguished from each other, but the brazilian population was well separated from the others. the hi ... | 1998 | 9879737 |
| uptake of rhodnius heme-binding protein (rhbp) by the ovary of rhodnius prolixus. | the uptake of rhbp (rhodnius heme-binding protein) by the ovaries of rhodnius prolixus was characterized. rhbp purified from occyte was labeled with 125i and used to study the process of uptake by the ovary in vivo and in vitro. after injection, the [125i]rhbp was readily removed from the hemolymph and accumulated especially in the ovary. the capacity of the ovary to take up [125i]rhbp from the hemolymph varied during the days following blood meal. it increased up to day 2, remained stable until ... | 1998 | 9880903 |