Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| cytochemical characterization of microvillar and perimicrovillar membranes in the posterior midgut epithelium of rhodnius prolixus. | perimicrovillar membranes (pmm) are structures present on the surface of midgut epithelial cells of the hematophagous insect, rhodnius prolixus. they cover the microvilli and are especially evident 10 days after blood meal, providing the compartmentalization of the enzymatic processes in the intestinal microenvironment. using an enzyme cytochemical approach, mg2+-atpase and ouabain-sensitive na+k+-atpase activities were observed in the plasma (or microvillar) membrane (mm) of midgut cells and in ... | 2009 | 18602023 |
| ecdysteroid receptor (ecr) is associated with microtubules and with mitochondria in the cytoplasm of prothoracic gland cells of rhodnius prolixus (hemiptera). | we have shown previously that ecr in larval rhodnius is present in the cytoplasm of various cell types and undergoes daily cycling in abundance in the cytoplasm (vafopoulou and steel, 2006. cell tissue res 323:443-455). it is unknown which organelles are associated with ecr. here, we report that cytoplasmic ecr in prothoracic gland cells is associated with both microtubules and mitochondria, and discuss the implications for both nuclear and non-genomic actions of ecr. ecr was localized immunohis ... | 2009 | 19847923 |
| cloning and characterization of dorsal homologues in the hemipteran rhodnius prolixus. | rhodnius prolixus is an ancient haematophagous hemipteran insect capable of mounting a powerful immune response. this response is transcriptionally regulated in part by transcription factors of the rel/nuclear factor kappa b (rel/nf-kappab) family. we have cloned and characterized three members of this transcription factor family in this insect. dorsal 1a is primarily expressed in early developmental stages. in contrast, dorsal 1b and 1c, both differentially spliced products of dorsal 1a, are ex ... | 2009 | 19754745 |
| behavioural and physiological state dependency of host seeking in the blood-sucking insect rhodnius prolixus. | vertebrate blood is essential for the growth and the reproduction of haematophagous insects. provided that hosts play the double role of food sources and predators, feeding on their blood exposes these insects to a high predation risk. therefore, it is expected that host seeking occurs only when insects need to feed. in the present study, we analyse how the feeding status affects the response to host-associated cues in the blood-sucking insect rhodnius prolixus. we show that the responsiveness t ... | 2009 | 19617431 |
| functional anatomy of vagina muscles in the blood-feeding insect, rhodnius prolixus. | the physiology of the muscles associated with the vagina in the blood-feeding insect, rhodnius prolixus stal, was investigated with the use of methylene blue staining to visualize the anatomy, and a micro force transducer to record spontaneous and neurally-evoked contractions. the vagina is associated with a dorsal muscle and a set of paired lateral muscles. the dorsal muscle extends from the base of the common oviduct to apodemes located laterally on sternite viii, the first genital segment. th ... | 2009 | 19573623 |
| synthesis and mobilization of glycogen and trehalose in adult male rhodnius prolixus. | the vector of chagas' disease, rhodnius prolixus, feeds exclusively on blood. the blood meals are slowly digested, and these insects wait some weeks before the next meal. during the life of an insect, energy-requiring processes such as moulting, adult gonadal and reproductive growth, vitellogenesis, muscular activity, and fasting, lead to increased metabolism. carbohydrates are a major source of energy and their mobilization is important. we determined the amounts of glycogen, trehalose, and glu ... | 2009 | 19514081 |
| fumigant insecticidal activity and repellent effect of five essential oils and seven monoterpenes on first-instar nymphs of rhodnius prolixus. | the aim of this study was to evaluate the fumigant and repellent activity of five essential oils (from eucalyptus, geranium, lavender, mint, and orange oil) and seven monoterpenes (eucalyptol, geraniol, limonene, linalool, menthone, linalyl acetate, and menthyl acetate) on first-instar nymphs of the bloodsucking bug rhodnius prolixus stahl (vector of chagas disease in several latin american countries). fumigant activity was evaluated by exposing the nymphs to the vapors emitted by 100 microl of ... | 2009 | 19496421 |
| the neuropeptidome of rhodnius prolixus brain. | we show a sensitive and straightforward off-line nano-lc-maldi-ms/ms workflow that allowed the first comprehensive neuropeptidomic analysis of an insect disease vector. this approach was applied to identify neuropeptides in the brain of rhodnius prolixus, a vector of chagas disease. this work will contribute to the annotation of genes in the ongoing r. prolixus genome sequence project. peptides were identified by de novo sequencing and comparisons to known neuropeptides from different organisms ... | 2009 | 19137558 |
| [effect of the desiccant dry-die-67 on rhodnius prolixus stal. bugs]. | 2009 | 6341798 | |
| [toxicity of the preparation drayon for the bug rhodnius prolixus stal (order hemiptera, family triatomidae)]. | 2009 | 803609 | |
| the triatominae species of french guiana (heteroptera: reduviidae). | an annotated list of the triatomine species present in french guiana is given. it is based on field collections carried out between 1993-2008, museum collections and a literature review. fourteen species, representing four tribes and six genera, are now known in this country and are illustrated (habitus). three species are recorded from french guiana for the first time: cavernicola pilosa, microtriatoma trinidadensis and rhodnius paraensis. the two most common and widely distributed species are ... | 2009 | 20140371 |
| physiological activity of neuropeptide f on the hindgut of the blood-feeding hemipteran, rhodnius prolixus. | current hypotheses propose that, in the invertebrates, neuropeptide f (npf), the vertebrate npy homologue, may be capable of regulating responses to diverse cues related to nutritional status and feeding. an investigation into the effects of drosophila melanogaster npf (drmnpf) and anopheles gambiae npf (angnpf) on hindgut physiology of rhodnius prolixus stal (heimptera: reduviidae) suggests a myoinhibitory role for these peptides and the r. prolixus native peptide. extracts of the central nervo ... | 2009 | 20050776 |
| behavioral and electrophysiological responses of triatoma brasiliensis males to volatiles produced in the metasternal glands of females. | in many insects, mate finding is mediated by volatile sex pheromones, but evidence for this phenomenon in triatomines (heteroptera: reduviidae) is still fragmentary. recently, it was shown that metasternal glands (mgs) are involved in producing signals related to the sexual communication of triatoma infestans and rhodnius prolixus. based on this, we tested whether mg volatiles could be involved in the sexual communication of triatoma brasiliensis. odor-mediated orientation responses were studied ... | 2009 | 19902303 |
| trypanosoma rangeli genotypes association with rhodnius prolixus and r. pallescens allopatric distribution in central america. | previous kdna polymorphism-based reports have revealed the existence of two trypanosoma rangeli genotypes (kp1+ and kp1-): sl and ssu rrna gene polymorphism-based studies have revealed that five genotypes (a-e) are distributed throughout different latin-american countries. some evidence has shown that the genotypes' biogeographical distribution is associated with sympatric rhodnius species. 12 t. rangeli isolates from humans and reservoirs from el salvador, guatemala, honduras, costa rica and pa ... | 2009 | 19778637 |
| immunogenic salivary proteins of triatoma infestans: development of a recombinant antigen for the detection of low-level infestation of triatomines. | triatomines are vectors of trypanosoma cruzi, the etiological agent of chagas disease in latin america. the most effective vector, triatoma infestans, has been controlled successfully in much of latin america using insecticide spraying. though rarely undertaken, surveillance programs are necessary in order to identify new infestations and estimate the intensity of triatomine bug infestations in domestic and peridomestic habitats. since hosts exposed to triatomines develop immune responses to sal ... | 2009 | 19841746 |
| allatostatin c and its paralog allatostatin double c: the arthropod somatostatins. | arthropods do not have one, but two genes encoding an allatostatin c-like peptide. the newly discovered paralog gene was called ast-cc, and the peptide which it is predicted to make was called allatostatin double c (astcc). genes for both allatostatin c (astc) and its paralog were found in the tick ixodes scapularis as well as dipteran, lepidopteran, coleopteran, aphidoidean and phthirapteran insect species. in addition partial or complete cdnas derived from ast-ccs were found in a number of spe ... | 2009 | 19063967 |
| invitro effect of canavalia ensiformis urease and the derived peptide jaburetox-2ec on rhodnius prolixus malpighian tubules. | ureases are metalloenzymes that are widespread among plants, fungi and bacteria. urease isoforms (jack bean urease-jbu and canatoxin) from canavalia ensiformis seeds are toxic to insects and fungi, suggesting a role in plant defense. the entomotoxic effect is due to the release of a 10-kda peptide by cathepsin-like enzymes in the insect's midgut. urease causes a decrease in post-feeding weight loss in rhodnius prolixus, suggesting an effect on water balance. to investigate how this impairment oc ... | 2009 | 19121321 |
| haplotype identification within trypanosoma cruzi i in colombian isolates from several reservoirs, vectors and humans. | genetic variability in the trypanosoma cruzi i group has recently been revealed in colombian isolates from humans, reservoirs and vectors. genomic rearrangements and the polymorphic regions in taxonomic markers, such as the miniexon gene, have led to the development of molecular tools to identify phylogenetic haplotypes in t. cruzi isolates. from genetic polymorphisms found in t. cruzi i isolates, they have been classified into four haplotypes according to their epidemiologic transmission cycles ... | 2009 | 19135020 |
| physalin b inhibits rhodnius prolixus hemocyte phagocytosis and microaggregation by the activation of endogenous paf-acetyl hydrolase activities. | the effects of physalin b (a natural secosteroidal chemical from physalis angulata, solanaceae) on phagocytosis and microaggregation by hemocytes of 5th-instar larvae of rhodnius prolixus were investigated. in this insect, hemocyte phagocytosis and microaggregation are known to be induced by the platelet-activating factor (paf) or arachidonic acid (aa) and regulated by phospholipase a(2) (pla(2)) and paf-acetyl hydrolase (paf-ah) activities. phagocytic activity and formation of hemocyte microagg ... | 2009 | 19232405 |
| state-dependency of host-seeking in rhodnius prolixus: the post-ecdysis time. | the source of blood of most haematophagous insects plays at the same time the double role of host and potential predator. feeding behaviour should be triggered only when necessary and should be completed as quickly as possible. from an epidemiological point of view, this modulation has an impact on the feeding frequency of disease vectors and, as a consequence, on the transmission of parasites. at present, not many data are available on the influence of the physiological state on the motivation ... | 2009 | 19418597 |
| diuretic and antidiuretic hormones in the blood-gorging bug rhodnius prolixus. | insect salt and water homeostasis is controlled by diuretic and antidiuretic hormones that can act upon the malpighian tubules, midgut, and hindgut. much is known about the physiological events stimulating diuresis and their signaling cascades; however, the factors inhibiting diuresis are less well known. an endogenous peptide in rhodnius prolixus inhibits absorption by the anterior midgut and secretion from the malpighian tubules. we have cloned the gene, sequenced this antidiuretic peptide, an ... | 2009 | 19456399 |
| the metasternal and brindley's glands of triatoma brasiliensis neiva (hemiptera: reduviidae). | triatoma brasiliensis neiva is the most important vector of the chagas' disease in the semiarid zones of north-eastern brazil. adult bugs have two main pairs of exocrine glands, the metasternal and the brindley's glands, which release volatiles possibly with defense, alarm and/or mating functions. to date, anatomical and histological studies of the metasternal and the brindley's glands in the genus triatoma are scarce and, considering the relevance of these exocrine glands, the present work aime ... | 2009 | 19488512 |
| the role of salivary and intestinal complement system inhibitors in the midgut protection of triatomines and mosquitoes. | saliva of haematophagous arthropods contain biomolecules involved directly or indirectly with the haematophagy process, and among them are encountered some complement system inhibitors. the most obvious function for these inhibitors would be the protection of the midgut against injury by the complement. to investigate this hypothesis, triatoma brasiliensis nymphs were forced to ingest human serum in conditions in which the protection of midgut by the inhibitors is bypassed. in these conditions, ... | 2009 | 19557176 |
| transmission dynamics of trypanosoma cruzi determined by low-stringency single primer polymerase chain reaction and southern blot analyses in four indigenous communities of the sierra nevada de santa marta, colombia. | this study attempted to evaluate the transmission dynamics of trypanosoma cruzi in four indigenous communities of sierra nevada de santa marta (snsm), colombia. low-stringency single primer-polymerase chain reaction (lssp-pcr) of the minicircles and southern blot analyses were used to characterize samples from patients, vectors, and reservoirs in these communities. the lssp-pcr profiles revealed a high genetic variability but with similarities among the parasites present in the samples of vector ... | 2009 | 19706903 |
| biology, diversity and strategies for the monitoring and control of triatomines--chagas disease vectors. | despite the relevant achievements in the control of the main chagas disease vectors triatoma infestans and rhodnius prolixus, several factors still promote the risk of infection. the disease is a real threat to the poor rural regions of several countries in latin america. the current situation in brazil requires renewed attention due to its high diversity of triatomine species and to the rapid and drastic environmental changes that are occurring. using the biology, behaviour and diversity of tri ... | 2009 | 19753457 |
| sylvatic triatominae: a new challenge in vector control transmission. | over the last 10 years, uruguay, chile and brazil have been certified as being free from disease transmission by triatoma infestans, the main domiciliated vector for chagas disease in the southern cone countries. this demonstrates that programmes addressing the vector for the disease's transmission are effective. these programmes have resulted in a dramatic decrease in the incidence of chagas disease in latin america. guatemala was certified a few months ago as being free from disease transmissi ... | 2009 | 19753461 |
| in vitro and in vivo documentation of quantum dots labeled trypanosoma cruzi--rhodnius prolixus interaction using confocal microscopy. | semiconductor quantum dots (qds) are highly fluorescent nanocrystals markers that allow long photobleaching and do not destroy the parasites. in this paper, we used fluorescent core shell quantum dots to perform studies of live parasite-vector interaction processes without any observable effect on the vitality of parasites. these nanocrystals were synthesized in aqueous medium and physiological ph, which is very important for monitoring live cells activities, and conjugated with molecules such a ... | 2009 | 19756738 |
| attraction of triatoma dimidiata and rhodnius prolixus (hemiptera: reduviidae) to combinations of host cues tested at two distances. | the "kissing bugs," triatoma dimidiata (latreille) and rhodnius prolixus (stål) (reduviidae: triatominae) are major vectors of chagas disease in central and south america. to further uncover the attraction to certain host cues by these vectors at long and short distances from their host, the behavioral responses of two life stages (fifth-instar nymphs and adult males) of these two species to different known or suspected attractants, alone or in combination, were investigated. tests were done usi ... | 2009 | 19769037 |
| genomic resources for invertebrate vectors of human pathogens, and the role of vectorbase. | high-throughput genome sequencing techniques have now reached vector biology with an emphasis on those species that are vectors of human pathogens. the first mosquito to be sequenced was anopheles gambiae, the vector for plasmodium parasites that cause malaria. further mosquitoes have followed: aedes aegypti (yellow fever and dengue fever vector) and culex pipiens (lymphatic filariasis and west nile fever). species that are currently in sequencing include the body louse pediculus humanus (typhus ... | 2009 | 18262474 |
| oral transmission of trypanosoma cruzi with opposing evidence for the theory of carnivory. | we present the first demonstration of oral transmission of trypanosoma cruzi to raccoons (procyon lotor), a natural reservoir host in the united states, by ingestion of trypomastigotes and infected bugs, but not infected tissue. to investigate an alternative, non-vector-based transmission method, we tested the hypothesis that raccoons scavenging on infected hosts results in patent infection. macerated tissue from selected organs infected with amastigote stages of t. cruzi was orally administered ... | 2009 | 18763853 |
| trypanosoma cruzi congenital transmission in wild bats. | trypanosoma cruzi congenital transmission in wild bats (molossus molossus), associated with infected rhodnius prolixus in a natural habitat from a rural locality in western venezuela, is reported. t. cruzi blood circulating trypomastigotes in a pregnant bat were detected by parasitological methods. polymerase chain reaction (pcr) assays carried out in samples from the heart and the fetus of the same infected female, revealed the presence of t. cruzi-specific dna in both of the tissues, demonstra ... | 2009 | 18823929 |
| trypanosoma cruzi: biological characterization of lineages i and ii supports the predominance of lineage i in colombia. | the causes of the particular distribution of both trypanosoma cruzi lineages throughout the american continent remain unknown. in colombia, t. cruzi i is the predominant group in both domestic and sylvatic cycles. here, we present the biological characterization of t. cruzi parasites belonging to both t. cruzi i and t. cruzi iib groups. our results show the inability of the t. cruzi iib clones to infect mammalian cells, produce trypomastigotes and replicate in rhodnius prolixus, the main vector ... | 2009 | 18950627 |
| the role of salivary nitrophorins in the ingestion of blood by the triatomine bug rhodnius prolixus (reduviidae: triatominae). | to assist haematophagy, rhodnius prolixus produces several bioactive molecules in its saliva which it injects into the host skin. the most abundant of these molecules are the nitrophorins (nps). in this work, we reduced the expression of np1-4 in the saliva of r. prolixus by rnai and evaluated the subsequent feeding performance of the bugs using the cibarial pump electromyogram either on the dorsal skin or on the tail vein of the mice. nps salivary mrna was reduced by >99% in comparison to contr ... | 2009 | 18992340 |
| arrest of oogenesis in the bug rhodnius prolixus challenged with the fungus aspergillus niger is mediated by immune response-derived pge2. | in this work we characterized the immune response of the insect rhodnius prolixus to a direct injection into the hemocoel of the non-entomopathogenic fungus aspergillus niger, and evaluated its consequences on host oogenesis. these animals were able to respond by mounting effective cellular and humoral responses to this fungus; these responses were shown, however, to have reproductive fitness costs, as the number of eggs laid per female was significantly reduced. the disturbance of egg formation ... | 2009 | 19059412 |
| a panel of ten microsatellite loci for the chagas disease vector rhodnius prolixus (hemiptera: reduviidae). | rhodnius prolixus is the main vector of chagas disease in venezuela, where it is found colonising rural housing consisting of unplastered adobe walls with palm and/or metal roofs. vector control failure in venezuela may be due to the invasion of houses by silvatic populations of r. prolixus found in palms. as part of a study to determine if domestic and silvatic populations of r. prolixus are isolated, thus clarifying the role of silvatic populations in maintaining house infestations, we constru ... | 2009 | 19061974 |
| alpha-glucosidase promotes hemozoin formation in a blood-sucking bug: an evolutionary history. | hematophagous insects digest large amounts of host hemoglobin and release heme inside their guts. in rhodnius prolixus, hemoglobin-derived heme is detoxified by biomineralization, forming hemozoin (hz). recently, the involvement of the r. prolixus perimicrovillar membranes in hz formation was demonstrated. | 2009 | 19742319 |
| trypanosoma rangeli: a new perspective for studying the modulation of immune reactions of rhodnius prolixus. | abstract: insects are exposed to a wide range of microorganisms (bacteria, fungi, parasites and viruses) and have interconnected powerful immune reactions. although insects lack an acquired immune system they have well-developed innate immune defences that allow a general and rapid response to infectious agents.over the last few decades we have observed a dramatic increase in the knowledge of insect innate immunity, which relies on both humoral and cellular responses. however, innate reactions t ... | 2009 | 19615044 |
| [action of insect growth inhibitors on aedes aegypti l. mosquitoes and rhodnius prolixus stal. bugs. iii. the activity of diarylidene cyclonones]. | 2009 | 364291 | |
| lipid mediators and vector infection: trypanosoma rangeli inhibits rhodnius prolixus hemocyte phagocytosis by modulation of phospholipase a2 and paf-acetylhydrolase activities. | in this work we investigated the effects of trypanosoma rangeli infection through a blood meal on the hemocyte phagocytosis in experiments using the 5th instar larvae of rhodnius prolixus. hemocyte phagocytic activity was strongly blocked by oral infection with the parasites. in contrast, hemocyte phagocytosis inhibition caused by t. rangeli infection was rescued by exogenous arachidonic acid (20 microg/insect) or platelet activating factor (paf; 1 microg/insect) applied by hemocelic injection. ... | 2008 | 18835273 |
| biological characterization of trypanosoma cruzi stocks from domestic and sylvatic vectors in sierra nevada of santa marta, colombia. | sierra nevada of santa marta is one of the most endemic regions of chagas disease in colombia. in this study, we compared the biological behavior and genetic features of trypanosoma cruzi stocks that were isolated from domestic and sylvatic insects in this area. rhodnius prolixus (from domestic environments) and triatoma dimidiata (from sylvatic, peridomestic and domestic environments) are the most important vectors in this region. genetic characterization showed that all stocks corresponded to ... | 2008 | 18804443 |
| comparative peptidomics of four related hemipteran species: pyrokinins, myosuppressin, corazonin, adipokinetic hormone, snpf, and periviscerokinins. | we performed the first comprehensive peptidomic analysis of neurohormones from hemipteran insects by analyzing the neuropeptides of two major neurohemal organs, namely the corpora cardiaca and abdominal perisympathetic organs. for the experiments we selected four related species of polyphagous stinkbugs (pentatomidae), three of which are known to attack several important food crops. peptide sequences were identified by maldi-tof mass spectrometry; tandem fragmentation of myosuppressin, snpf, cap ... | 2008 | 18201800 |
| recent advances in understanding the mechanism of hemozoin (malaria pigment) formation. | the recent literature on hemozoin/beta-hematin formation is reviewed, with an emphasis on the mechanism of its formation. recent findings from unrelated organisms that produce hemozoin, namely the malaria parasite plasmodium falciparum, the worm schistosoma mansoni and the kissing bug rhodnius prolixus all of which consume human hemoglobin show that the formation of this crystalline substance occurs within or at the surface of lipids. biomimetic experimental models of the lipid-water interface a ... | 2008 | 18226838 |
| immune depression in rhodnius prolixus by seco-steroids, physalins. | a comparative study of the effects of physalins, seco-steroidal substances of physalis angulata (solanaceae), on the immune reactions of r. prolixus was carried out. ecdysis and mortality were not affected by treatment with physalins b, d, f or g (1-10 microg/ml of blood meal). r. prolixus larvae fed with blood containing physalins and inoculated with 1 microl of enterobacter cloacae beta12 (5 x 10(3)/insect) exhibited mortality rates three times higher than controls. the insects treated with ph ... | 2008 | 18234209 |
| identification and characterization of two novel lysozymes from rhodnius prolixus, a vector of chagas disease. | lysozymes have been described in invertebrates as digestive or immune molecules. we report here the characterization of two novel c-type lysozymes, rplys-a (eu250274) and rplys-b (eu250275), isolated from the fat body and digestive tract of immune stimulated rhodnius prolixus, a major vector of chagas disease. transcriptional profiles indicate that the temporal and spatial expression patterns of these two peptides are very different. rplys-a is expressed predominantly in the midgut after ingesti ... | 2008 | 18258253 |
| microsatellite markers from the chagas disease vector, rhodnius prolixus (hemiptera, reduviidae), and their applicability to rhodnius species. | ten microsatellites were isolated and characterized from a partial genomic library of rhodnius prolixus, the principal chagas disease vector in venezuela, colombia and central america. these polymorphic molecular markers could be particularly useful in chagas disease control initiatives. a wider applicability of the primer-pairs isolated was shown, from 6 to 10 loci being amplifiable in five out of the ten rhodnius species tested, namely r. domesticus, r. nasutus, r. neglectus, r. neivai and r. ... | 2008 | 18304894 |
| genetic transformation of a corynebacterial symbiont from the chagas disease vector triatoma infestans. | insect-borne diseases have experienced a troubling resurgence in recent years. emergence of resistance to pesticides greatly hampers control efforts. paratransgenesis, or the genetic transformation of bacterial symbionts of disease vectors, is an alternative to traditional approaches. previously, we developed paratransgenic lines of rhodnius prolixus, a vector of chagas disease in central america. here, we report identification of a corynebacterial species as a symbiont of triatoma infestans, a ... | 2008 | 18331732 |
| molecular genetics reveal that silvatic rhodnius prolixus do colonise rural houses. | rhodnius prolixus is the main vector of chagas disease in venezuela. here, domestic infestations of poor quality rural housing have persisted despite four decades of vector control. this is in contrast to the southern cone region of south america, where the main vector, triatoma infestans, has been eliminated over large areas. the repeated colonisation of houses by silvatic populations of r. prolixus potentially explains the control difficulties. however, controversy surrounds the existence of s ... | 2008 | 18382605 |
| ecto-phosphatase activity on the external surface of rhodnius prolixus salivary glands: modulation by carbohydrates and trypanosoma rangeli. | the salivary glands of insect's vectors are target organs to study the vectors-pathogens interactions. rhodnius prolixus an important vector of trypanosoma cruzi can also transmit trypanosoma rangeli by bite. in the present study we have investigated ecto-phosphatase activity on the surface of r. prolixus salivary glands. ecto-phosphatases are able to hydrolyze phosphorylated substrates in the extracellular medium. we characterized these ecto-enzyme activities on the salivary glands external sur ... | 2008 | 18407240 |
| preliminary characterization of a rhodnius prolixus hemolymph trypanolytic protein, this being a determinant of trypanosoma rangeli kp1(+) and kp1(-) subpopulations' vectorial ability. | rhodnius prolixus is the main trypanosoma rangeli vector in several latin-american countries and is susceptible to infection with kp1(+) strains; however, it presents an invasion-resistant response to kp1(-) strains. the present work has identified a trypanolytic protein against t. rangeli kp1(-) in the r. prolixus hemolymph which was fractioned with ammonium sulfate (following dialysis). the results revealed a protein component which did not depend on divalent cations for its biological functio ... | 2008 | 18425269 |
| characteristics of plasminogen binding to trypanosoma cruzi epimastigotes. | the binding constants of the interaction between plasminogen and trypanosoma cruzi epimastigotes were determined. an indirect method in which the bound plasminogen is detached from the cell by epsilon-aminocaproic acid and a direct method through biotinylated plasminogen were used. the analyses revealed a dissociation constant (kd) from 0.4 to 1.2microm, these values being compatible with recognition in vivo. moreover, epimastigotes from the gut of rhodnius prolixus were able to bind plasminogen ... | 2008 | 18501871 |
| learning and orientation to odor in the bug rhodnius prolixus stal 1859 under laboratory conditions. | two experiments are described investigating learning and orientation in the triatomine rhodnius prolixus. in experiment 1, pavlovian conditioning was investigated. the experiment differed from our previous work in that the intensity of the conditioned and unconditioned stimuli were reduced and the number of training trials increased. once again, no evidence for pavlovian conditioning was found. in experiment 2, an "orientation arena" was developed in which the orientation of r. prolixus to a hum ... | 2008 | 18509679 |
| isolation, cloning, and expression mapping of a gene encoding an antidiuretic hormone and other capa-related peptides in the disease vector, rhodnius prolixus. | after a blood meal, rhodnius prolixus undergoes a rapid diuresis to eliminate excess water and salts. during the voiding of this primary urine, r. prolixus acts as a vector of chagas' disease, with the causative agent, trypanosoma cruzi, infecting the human host via the urine. diuresis in r. prolixus is under the neurohormonal control of serotonin and peptidergic diuretic hormones, and thus, diuretic hormones play an important role in the transmission of chagas' disease. although diuretic hormon ... | 2008 | 18511504 |
| is rhodnius prolixus (triatominae) invading houses in central brazil? | sylvatic triatomines of the genus rhodnius commonly fly into houses in latin america, maintaining the risk of chagas disease transmission in spite of control efforts. in the recent past, adult bugs collected inside houses in central brazil were identified as r. prolixus, a primary disease vector whose natural geographical range excludes this region. three nearly sibling species (r. neglectus, r. nasutus, and r. robustus), secondary vectors with limited epidemiological significance, occur natural ... | 2008 | 18550022 |
| expression of gp82 and gp90 surface glycoprotein genes of trypanosoma cruzi during in vivo metacyclogenesis in the insect vector rhodnius prolixus. | trypanosoma cruzi, the parasite causing chagas' disease, relies on triatomines for its transmission. t. cruzi metacyclic trypomastigotes express gp82 and gp90, which are developmentally regulated surface proteins that have been implicated in host cell invasion. we used quantitative rt-pcr to quantify gp90 and gp82 mrna levels expressed by t. cruzi in the digestive tract of experimentally infected rhodnius prolixus at different times post infection. translation of these transcripts was assessed b ... | 2008 | 17889817 |
| trypanosoma cruzi infection is enhanced by vector saliva through immunosuppressant mechanisms mediated by lysophosphatidylcholine. | trypanosoma cruzi, the etiological agent of chagas disease, is transmitted by bug feces deposited on human skin during a blood meal. however, parasite infection occurs through the wound produced by insect mouthparts. saliva of the triatominae bug rhodnius prolixus is a source of lysophosphatidylcholine (lpc). here, we tested the role of both triatomine saliva and lpc on parasite transmission. we show that vector saliva is a powerful inducer of cell chemotaxis. a massive number of inflammatory ce ... | 2008 | 18794282 |
| hyaluronidase of bloodsucking insects and its enhancing effect on leishmania infection in mice. | salivary hyaluronidases have been described in a few bloodsucking arthropods. however, very little is known about the presence of this enzyme in various bloodsucking insects and no data are available on its effect on transmitted microorganisms. here, we studied hyaluronidase activity in thirteen bloodsucking insects belonging to four different orders. in addition, we assessed the effect of hyaluronidase coinoculation on the outcome of leishmania major infection in balb/c mice. | 2008 | 18820742 |
| blockades of phospholipase a(2) and platelet-activating factor receptors reduce the hemocyte phagocytosis in rhodnius prolixus: in vitro experiments. | the hemocytes phagocytosis in response to microorganisms may play an important role in the cellular immune responses of insects. here, we have evaluated the effects of the platelet-activating factor (paf) and eicosanoids in the phagocytosis of hemocyte monolayers of rhodnius prolixus to the yeast saccharomyces cerevisiae. experiments showed that the phagocytosis of yeast cells by rhodnius hemocytes is very efficient in both controls and cells treated with paf and arachidonic acid. phagocytosis o ... | 2008 | 18036540 |
| haemozoin formation. | formation of malaria pigment or haemozoin is the major route of haem detoxification in the malaria parasite plasmodium falciparum as well as several other species of haematophagous organisms, including other plasmodium species, helminth worms such as schistosoma mansoni and blood-sucking insects such as rhodnius prolixus. recent advances in our understanding of the formation of haemozoin, both from new observations that it is formed within lipid bodies in p. falciparum and s. mansoni and biomime ... | 2008 | 18083247 |
| differential actions of diuretic factors on the malpighian tubules of rhodnius prolixus. | the effects of corticotropin-releasing factor (crf)-related (zoonedh), calcitonin (ct)-related (rhoprdh(31)) and kinin-related (leucokinin i) peptides on the ion composition of fluid secreted by upper rhodnius prolixus malpighian tubules and on kcl reabsorption by the lower tubules were assessed. zoonedh stimulated fluid secretion while increasing the [na(+)] of secreted fluid at the expense of [k(+)]. upper tubules responded to zoonedh with a characteristic triphasic change in the transepitheli ... | 2008 | 18083731 |
| phagocytosis of latex beads and bacteria by hemocytes of the triatomine bug rhodnius prolixus (hemiptera: reduvidae). | insect circulating hemocytes are primarily responsible for the immune defense against parasites and pathogens. here, we have analyzed phagocytosis of both biotic (bacteria) and abiotic (latex) particles by circulating hemocytes of 5th-instar nymphs of the triatomine bug rhodnius prolixus. the following hemocyte types were identified: prohemocytes, plasmatocytes, granulocytes, oenocytoids and adipohemocytes. there was a considerable change in the relative percentage of plasmatocytes and prohemocy ... | 2008 | 17368036 |
| degradation of the neolignan, burchellin in the hemolymph of the bloodsucking insect rhodnius prolixus. | the neolignan, burchellin, a natural compound that reduces urine excretion in larvae of the bloodsucking bug, rhodnius prolixus, a vector of chagas' disease, is rapidly degraded in the hemolymph of the insect. the main product that accumulates in this tissue has been shown to be piperonyl alcohol. other catabolites have been identified by gc-ms analysis. | 2008 | 17904765 |
| distribution and activity of a dippu dh31-like peptide in the large milkweed bug oncopeltus fasciatus. | the milkweed bug, oncopeltus fasciatus, is a plant feeding hemipteran. while there has been much research done on the neurohormonal control of the post-feeding diuresis in the blood-feeding hemipteran, rhodnius prolixus, little is known about the control of the post-feeding diuresis in o. fasciatus. one of the neurohormones that may play a role in this rapid diuresis belongs to the calcitonin-like diuretic hormone (dh31) family of insect peptides. in this study we demonstrate the presence of dh3 ... | 2008 | 18206263 |
| assignment of the ferriheme resonances of high- and low-spin forms of the symmetrical hemin-reconstituted nitrophorins 1-4 by 1h and 13c nmr spectroscopy: the dynamics of heme ruffling deformations. | the four major nitrophorins (nps) of the adult blood-sucking insect rhodnius prolixus have been reconstituted with the "symmetrical hemin" 2,4-dimethyldeuterohemin, and their nmr spectra have been investigated as the high-spin (s=5/2) aqua and low-spin (s=1/2) n-methylimidazole (nmeim) and cyanide complexes. the nmeim complexes allow assignment of the high-spin hemin resonances by saturation transfer difference spectroscopy. the cyanide complexes were investigated as paramagnetic analogues of th ... | 2008 | 18458965 |
| dynamics of lipid accumulation by the fat body of rhodnius prolixus: the involvement of lipophorin binding sites. | in insects, lipids are stored in the fat body, mainly as triacylglycerol (tag). in rhodnius prolixus, a hematophagous hemipteran, lipids are accumulated after blood meal to be used later on. in adult females, at the second day after feeding, the amount of tag was 57+/-17 microg/fat body, it increased almost five times and at fourth day it was 244+/-35 microg/fat body. tag content remained constant until day 13, but it then decreased and, at day 20th it was very low (31+/-4.9 microg/fat body). ra ... | 2008 | 18395740 |
| metasternal gland volatiles and sexual communication in the triatomine bug, rhodnius prolixus. | twelve compounds produced by the metasternal glands (mgs) of the triatomine bug rhodnius prolixus were identified by solid phase microextraction (spme) combined with coupled gas chromatography-mass spectrometry (gc-ms) using achiral and chiral columns. all substances were ketones or alcohols, and the same compound profile was found in the secretions produced by either sex. the most abundant compounds were 2-methyl-3-buten-2-ol, (2s)-pentanol, (3e)-2-methyl-3-penten-2-ol, and (2r/2s)-4-methyl-3-p ... | 2008 | 18317844 |
| amino acid sequence and biological activity of a calcitonin-like diuretic hormone (dh31) from rhodnius prolixus. | diuresis in the blood-gorging hemipteran rhodnius prolixus is under neurohormonal control and involves a variety of processes and tissues. these include ion and water movement across the epithelium of the crop and the malpighian tubules, and muscle contractions of the crop, hindgut and dorsal vessel, which facilitate mixing of the blood-meal, mixing of the haemolymph, as well as the expulsion of waste. one of the neurohormones that might play a role in this rapid diuresis belongs to the calciton ... | 2008 | 18203994 |
| characterization of neuropeptide f-like immunoreactivity in the blood-feeding hemipteran, rhodnius prolixus. | the invertebrate neuropeptide y (npy) homolog, neuropeptide f (npf), has been characterized for a wide range of invertebrate phyla, including platyhelminthes, molluscs, and arthropods. current hypotheses suggest that npf may be capable of regulating responses to diverse external cues related to nutritional status and feeding. the qualitative and quantitative distribution of an npf-like peptide in fifth instar rhodnius prolixus was undertaken using an antiserum raised against drosophila npf. immu ... | 2008 | 18201798 |
| decrease in deet repellency caused by nitric oxide in rhodnius prolixus. | n,n-diethyl-3-methylbenzamide (deet) is widely used as an insect repellent; however, little is known about its mode of action. on the other hand, nitric oxide (no) participates in the olfaction transduction pathway of insects. in this work, nitroso-acetyl-cysteine (snac), a nitric oxide donor, or dibutyril-cyclic-gmp (db-cgmp), the cyclic nucleotide analog, were applied on fifth instar nymphs of rhodnius prolixus before exposing them to deet, to obtain information about the possible role of no/c ... | 2008 | 18088059 |
| carbohydrate accumulation and utilization by oocytes of rhodnius prolixus. | the processes of accumulation and mobilization of carbohydrate stores in eggs of rhodnius prolixus were analyzed. during oogenesis, the total amounts of glycogen, glucose, and trehalose increased with an accumulation of proteins, especially when oocytes grew from 1.0 to 1.5 mm in length. at 2.0 mm length, when oocytes were ready for oviposition, nutrient reserves did not increase appreciably and trehalose content decreased. mating did not affect the final content of carbohydrates or proteins in ... | 2008 | 18064701 |
| temporal modulation and adaptive control of the behavioural response to odours in rhodnius prolixus. | it has been demonstrated in several insect species that a circadian clock makes the whole of antennal chemoreceptors more sensitive during a particular temporal window every day. this assessment raises the question about how insects exhibiting bimodal activity handle their sensitivity to odours which are relevant at different moments of the day. to shed some light on this problem, we studied in rhodnius prolixus the daily dynamics of their responsiveness to co(2) (host-associated cue) and aggreg ... | 2008 | 18692504 |
| laboratory evaluation of the effects of triflumuron on the development of rhodnius prolixus nymph. | studies were carried out to evaluate the efficacy of the growth regulator, triflumuron (tfm) (starycide sc 480 bayer), for disrupting the development of rhodnius prolixus fifth-instar nymph by oral, topical or continuous treatment. all treatments were able to induce high levels of mortality, delay development and molt inhibition. oral treatment induced molt inhibition in all insects that survived at doses of 0.25, 0.50 and 5.0 mg/ml of a blood meal. the highest levels of both mortality in 24 h a ... | 2008 | 19148427 |
| assignment of ferriheme resonances for high- and low-spin forms of nitrophorin 3 by h and c nmr spectroscopy and comparison to nitrophorin 2: heme pocket structural similarities and differences. | nitrophorin 3 (np3) is the only one of the four major no-binding heme proteins found in the saliva of the blood-sucking insect rhodnius prolixus (also called the kissing bug) for which it has not been possible to obtain crystals of diffraction quality for structure determination by x-ray crystallography. thus we have used nmr spectroscopy, mainly of the hyperfine-shifted ferriheme substituent resonances, to learn about the similarities and differences in the heme pocket and the iron active site ... | 2008 | 19262680 |
| spectroscopic and functional characterization of nitrophorin 7 from the blood-feeding insect rhodnius prolixus reveals an important role of its isoform-specific n-terminus for proper protein function. | nitrophorins (nps) are a class of no-transporting and histamine-sequestering heme b proteins that occur in the saliva of the bloodsucking insect rhodnius prolixus. a detailed study of the newly described member, np7, is presented herein. no association constants for np7 [kiii(eq)(no)] reveal a drastic change when the ph is varied from 5.5 (reflecting the insect's saliva) to slightly above plasma ph (7.5) (>10(9) m-1 --> 4.0 x 10(6) m-1); thus, the protein promotes the storage of no in the insect ... | 2007 | 17958381 |
| effects of retinoids and juvenoids on moult and on phenoloxidase activity in the blood-sucking insect rhodnius prolixus. | retinoic acid and insect juvenile hormone (jh) are structurally related terpenoids which are widespread in nature and are involved in many biological events such as morphogenesis, embryogenesis and cellular differentiation. here, we investigated the effects of the retinoids 9-cis retinoic acid (9cisra), all trans retinol (atroh), all trans retinoic acid (atra) and the juvenoids methoprene (met) and jh injection on moult and on phenoloxidase activity in the blood-sucking insect rhodnius prolixus. ... | 2007 | 17686447 |
| neuroanatomical relations of prothoracicotropic hormone neurons with the circadian timekeeping system in the brain of larval and adult rhodnius prolixus (hemiptera). | this paper reports the localization in the rhodnius prolixus brain of neurons producing the key neuropeptide that regulates insect development, prothoracicotropic hormone (ptth) and describes intimate associations of the ptth neurons with the brain circadian timekeeping system. immunohistochemistry and confocal laser scanning microscopy revealed that the ptth-positive neurons in larvae are located in a single group in the lateral protocerebrum. their number increases from two in the last larval ... | 2007 | 17534946 |
| perimicrovillar membranes promote hemozoin formation into rhodnius prolixus midgut. | rhodnius prolixus is a hematophagous insect that ingests large quantities of blood in each blood-feeding session. this ingested blood provides important nutrients to sustain the insect's oogenesis and metabolic pathways. during the digestive process, however, huge amounts of heme are generated as a consequence of the hemoglobin breakdown. heme is an extremely dangerous molecule, since it can generate reactive oxygen species in the presence of oxygen that impair the normal metabolism of the insec ... | 2007 | 17517329 |
| rhodnius prolixus malpighian tubules and control of diuresis by neurohormones. | rhodnius prolixus malpighian tubules (mts) are a good model for fluid and ion secretion studies in view of the dramatic postprandial diuresis, which follows its massive blood meals. ingestion of a blood meal equals to 10-12 times their initial body mass, leads to rapid activation of high output by excretory system, which eliminates 40-50% of the fluid mass. secretion of ions and water is stimulated 1000-fold by serotonin and diuretic hormone. these hormones cooperate synergistically to activate ... | 2007 | 17401478 |
| allosteric regulation of 6-phosphofructo-1-kinase activity of fat body and flight muscle from the bloodsucking bug rhodnius prolixus. | 6-phosphofructo-1-kinase (phosphofructokinase; pfk) activity from rhodnius prolixus, a haematophagous insect which is usually a poor flyer, was measured and compared in two metabolically active tissues - flight muscle and fat body. the activity of this important regulatory glycolytic enzyme was much more pronounced in muscle (15.1 +/- 1.4 u/mg) than in fat body extracts (3.6+/-0.4 u/mg), although the latter presented higher levels of enzyme per protein content, as measured by western-blotting. m ... | 2007 | 17401475 |
| calcium-regulated fusion of yolk granules is important for yolk degradation during early embryogenesis of rhodnius prolixus stahl. | this study examined the process of membrane fusion of yolk granules (ygs) during early embryogenesis of rhodnius prolixus. we show that eggs collected at days 0 and 3 after oviposition contain different populations of ygs, for example day-3 eggs are enriched in large ygs (lygs). day-3 eggs also contain the highest free [ca(2+)] during early embryogenesis of this insect. in vitro incubations of day-0 ygs with [ca(2+)] similar to those found in day-3 eggs resulted in the formation of lygs, as obse ... | 2007 | 17170157 |
| the interaction of feeding and mating in the hormonal control of egg production in rhodnius prolixus. | the evidence relating feeding and mating to hormonal control of egg production in rhodnius prolixus is reviewed from two perspectives. it identifies crucial areas in which information is lacking, and it attempts to relate the findings, most of which have been obtained on laboratory colonies isolated for many years, to the sylvan life of the insect as an opportunistic micropredator. | 2007 | 17126364 |
| overexpression in escherichia coli and functional reconstitution of the liposome binding ferriheme protein nitrophorin 7 from the bloodsucking bug rhodnius prolixus. | a number of ferriheme proteins, termed nitrophorins (nps), occur in the saliva of the bloodsucking insect rhodnius prolixus ('kissing bug'), which is a vector for chagas' disease. nitrophorins bind the heme b cofactor in the beta-barrel of their lipocalin fold, which is further anchored through a proximal histidine-fe(iii) bond. the distal fe(iii) coordination site then binds nitric oxide (no) for delivery into a host's tissues during blood feeding, where, upon no release, the distal fe(iii) sit ... | 2007 | 17428677 |
| differential modulation of rhodnius prolixus nitric oxide activities following challenge with trypanosoma rangeli, t. cruzi and bacterial cell wall components. | nitric oxide (no) is a key immune effector and signaling molecule in many organisms. however, the contribution no makes towards insect immunity has received little attention, particularly in non-dipteran species. in this study, tissue- and time-specific alterations in no synthase (nos) gene expression and no production were documented in the hemipteran vector of chagas' disease, rhodnius prolixus, following in vivo immune challenge by trypanosoma cruzi, t. rangeli and crude bacterial lipopolysac ... | 2007 | 17456439 |
| [using elisa for identifying triatominae feeding behaviour in colombia]. | standardising the elisa technique for identifying triatomine insects' feeding behaviour. | 2007 | 18209827 |
| trypanosoma cruzi: involvement of glycoinositolphospholipids in the attachment to the luminal midgut surface of rhodnius prolixus. | trypanosoma cruzi epimastigotes adhere in vivo to the luminal surface of their triatomid vector digestive tract by molecular mechanisms, as yet, unknown. here, we show that the administration of 0.5 microm epimastigote major surface glycoinositolphospholipids (gipls) to the infected bloodmeal inhibits up to 90% parasite infection in rhodnius prolixus. the parasite behavior was investigated in vitro using fragments of the insect midgut. the addition of gipls in concentration as low as 50-100 nm i ... | 2007 | 17306256 |
| rhodnius prolixus: identification of immune-related genes up-regulated in response to pathogens and parasites using suppressive subtractive hybridization. | we report the identification of immune-related molecules from the fat body, and intestine of rhodnius prolixus, an important vector of chagas disease. insects were challenged by introducing pathogens or trypanosoma cruzi, the parasite that causes chagas disease, into the hemocoel. rna from intestines, or fat body were isolated 24h after stimulation. we used suppressive subtractive hybridization to identify immune-related genes, generated three subtracted libraries, sequenced the clones and assem ... | 2007 | 16824597 |
| exploring the role of insect host factors in the dynamics of trypanosoma cruzi-rhodnius prolixus interactions. | members of the subfamily triatominae, family reduviidae, comprise a large number of insect species of which some are vectors of trypanosoma cruzi, the causative agent of chagas' disease. this article outlines research on the process of transformation and the dynamics of developmental stages of trypanosoma cruzi in the triatomine insect hosts. special attention is given to the interactions of parasites with gut molecules, and the gut environment, and with host developmental physiology and intesti ... | 2007 | 17141801 |
| trypanosoma cruzi: attachment to perimicrovillar membrane glycoproteins of rhodnius prolixus. | studies were carried out to identify proteins involved in the interface of trypanosoma cruzi with the perimicrovillar membranes (pmm) of rhodnius prolixus. video microscopy experiments demonstrated high level of adhesion of t. cruzi dm 28c epimastigotes to the surface of posterior midgut cells of non-treated r. prolixus. the parasites however were unable to attach to gut cells obtained from decapitated or azadirachtin-treated insects. the influence of carbohydrates on the adhesion to insect midg ... | 2007 | 17250827 |
| morphometric evidence for a possible role of rhodnius prolixus from palm trees in house re-infestation in the state of barinas (venezuela). | the main vector of chagas disease in venezuela is rhodnius prolixus. specimens of rhodnius sp., identified elsewhere as r. prolixus by molecular tools, were collected in barinas state (venezuela) before insecticide application, and compared by morphometric techniques with post-spraying, re-infesting insects after control. geometric morphometry was applied, allowing separate analyses of shape and size. the idea of a single species sharing silvatic and domestic/peri-domestic ecotopes was supported ... | 2007 | 17306204 |
| replication of flock house virus in three genera of medically important insects. | flock house virus (family nodaviridae, genus alphanodavirus, fhv) was originally isolated from grass grubs costelytra zealandica (white) (coleoptera: scarabaeidae) in new zealand and belongs to a family of divided genome, plus-sense rna insect viruses. fhv replicates in insects, a nematode, plants, and yeast. we previously reported replication of fhv in four genera of mosquitoes and expression of green fluorescent protein in aedes aegypti (l.) produced by an fhv-based vector. we report here that ... | 2007 | 17294927 |
| [population structure and genetic variability of rhodnius prolixus (hemiptera: reduviidae) from different geographic areas of colombia]. | rhodnius prolixus is the most important vector of chagas disease in colombia. genetic characterization of this species is useful to understand its potential of dispersion. the distribution of the vector and the genetic population structure are important factors for the adequate implementation of control programs and epidemiological surveillance of chagas disease. | 2007 | 18154243 |
| [comparison of feeding and defecation patterns of rhodnius colombiensis and rhodnius prolixus(hempitera, reduviidae, triatominae) under laboratory conditions]. | rhodnius colombiensis occasionally comes into human dwellings and consequently its role as an important potential vector in the transmission of american trypanosomiasis has been suggested. | 2007 | 18154250 |
| [updated geographical distribution and ecoepidemiology of the triatomine fauna (reduviidae: triatominae) in colombia]. | information concerning triatomine records from provinces and municipalities was accumulated-including data indicating natural infections with trypanosomatides-that has been previously published or reported by colombian provincial health services and research institutes. altitude appeared to be the main factor responsible for the distribution of the insects. illustrations summarize the information provided by the above records. a triatomine fauna classification is presented that corresponds to th ... | 2007 | 18154255 |
| do haematophagous bugs assess skin surface temperature to detect blood vessels? | it is known that some blood-sucking insects have the ability to reach vessels under the host skin with their mouthparts to feed blood from inside them. however, the process by which they locate these vessels remains largely unknown. less than 5% of the skin is occupied by blood vessels and thus, it is not likely that insects rely on a "random search strategy", since it would increase the probability of being killed by their hosts. indeed, heterogeneities along the skin surface might offer exploi ... | 2007 | 17895973 |
| biochemical properties of the major proteins from rhodnius prolixus eggshell. | two proteins from the eggshell of rhodnius prolixus were isolated, characterized and named rp30 and rp45 according to their molecular masses. purified proteins were used to obtain specific antiserum which was later used for immunolocalization. the antiserum against rp30 and rp45 detected their presence inside the follicle cells, their secretion and their association with oocyte microvilli. both proteins are expressed during the final stage of vitellogenesis, preserved during embryogenesis and di ... | 2007 | 17916507 |
| chagas disease in andean countries. | the andean countries' initiative (aci) for controlling chagas disease was officially created in 1997 within the framework of the hipolito unanue agreement (unanue) between the ministries of health of colombia, ecuador, peru, and venezuela. its objective was to interrupt transmission via vector and transfusion in the region, taking into account that there are 12.5 million people at risk in the four andean countries forming the initiative in the area and around 3 million people are infected by try ... | 2007 | 17891273 |
| acid phosphatase activity distribution in salivary glands of triatomines (heteroptera, reduviidae, triatominae). | acid phosphatase activity (gömori technique) in salivary gland cells was investigated in adult insects (males and females) of four species of triatomines: triatoma infestans, panstrongylus megistus, rhodnius neglectus, and rhodnius prolixus. binucleated cells with bulky and polyploidy nuclei were detected, with acid phosphatase activity in the heterochromatin and nucleolus, which showed the most intense response. thus, the activity of these phosphatases during rrna molecule transcription, possib ... | 2007 | 17469069 |
| [epidemiology of chagas disease in andrés eloy blanco, lara, venezuela: triatomine infestation and human seroprevalence]. | a seroepidemiological survey and vector captures were performed in four rural communities in andrés eloy blanco, lara state, venezuela. systematic random sampling was based on family clusters, with samples drawn from 869 individuals to determine anti-trypanosoma cruzi and anti-leishmania sp. antibodies by indirect immunofluorescence. positive individuals were defined as > or = 1:32 for anti-t. cruzi antibody and non-reactive to leishmania sp. antigen, revealing an antibody frequency of 6.9% (n = ... | 2007 | 17486235 |
| risk factors for trypanosoma cruzi human infection in barinas state, venezuela. | this study attempted to quantify the transmission of trypanosoma cruzi in children less than 15 years of age in barinas state, venezuela and investigate risk factors for infection. among 3,296 children, 4 (0.12%) were seropositive. the mother of one child also was also seropositive, which suggested that congenital transmission is a possible risk factor for chagas disease in this area. seroprevalence among the dwellers of 10 localities was 3.3%. rhodnius prolixus was detected in 7 localities and ... | 2007 | 17488916 |
| lipid metabolism in rhodnius prolixus (hemiptera: reduviidae): role of a midgut triacylglycerol-lipase. | the utilization of dietary lipids was studied in adult females of rhodnius prolixus with the use of radiolabeled triacylglycerol (tag). it was shown that (3)h-triolein, when added to blood meal, was hydrolyzed to free fatty acids in the posterior midgut lumen. subsequently, free fatty acids were absorbed by posterior midgut epithelium and used in the synthesis of phospholipids, diacylglycerol (dag) and tag. phospholipids, dag and free fatty acids were then found in hemolymph, from where they wer ... | 2007 | 17517335 |
| effect of ectoparasitic pimeliaphilus plumifer mites (acari: pterygosomatidae) on meccus pallidipennis (hemiptera: reduviidae) and several other chagas' disease vectors under laboratory conditions. | several biological parameters were evaluated to determine the capacity of pimeliaphilus plumifer as biological control agent of triatominae bugs. when p. plumifer and bugs of a variety of triatomine species were forced together in cages in the laboratory, the incidence of mite infestation was the following: meccus pallidipennis > m. bassolsae > triatoma rubida > m. longipennis > m. picturatus, and practically no mites were found on t. infestans and rhodnius prolixus. adults and hexapod larvae of ... | 2007 | 17549587 |