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Sample records for rhodnius prolixus stal

  1. Mecanismo antidiurético en Rhodnius Prolixus (Stal, 1859 (Hemiptera, Reduviidae

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    Ivonne Gómez

    1986-12-01

    Full Text Available Se propone para R. prolixus un mecanismo antidiurético, cuya actividad se pone de manifiesto una vez transcurrido el periodo diurético y se mantiene hasta que el insecto es alimentado nuevamente. Presumiblemente este mecanismo actua a nivel del esfinter rectal proximal y es inhibido por la ingesta, distención mecanica del buche y desinhibición central por decapitación. Se sugiere que la actividad antidiurética es mantenida por vía nerviosa y se modifica cuando hay distensión del buche o canudo es interrumpida la senãl nerviosa por decapitación. Se pone de manifiesto que la excreción de orina en R. prolixus no es controlada exclusivamente por la hormona diurética, sino que factores no ligados a la hemolinfa mantienen en estado diurético y no diurético a los insectos.An antidiuretic mechanism is proposed for Rhodnius prolixus, whose activity is manifested when the diuretic phase has terminated and is maintained until the insect has fed again. Presumably this mechanism acts at the level of the proximal rectal sphincter and is inhibited by ingestion, mechanical distension of the gut and central desinhibition by decapitation. It is suggested that the antidiuretic activity is maintained by the nervous system and is modified when there is distention of the gut or when the nervous signal is interrupted by decapitacion. It is demonstrated that the excretion of urine in R. prolixus is not controlled exclusively by the diuretic hormone, but rather that factors not linked to the haemolvmph maintain the insects in a diuretic or nondiuretic state.

  2. Efecto de la alternación de fuentes sanguíneas sobre la fecundidad y la fertilidad de Rhodnius prolixus Stal (Heteroptera: Reduviidae

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    Elis José Aldana

    2009-04-01

    Full Text Available En este trabajo se evidencia que si el éxito reproductivo de Rhodnius prolixus Stal está relacionado a la fuente alimentaria, entonces las necesidades biológicas del insecto son satisfechas en modos diferentes según el tipo de alternancia entre dichas fuentes de alimentación; tales diferencias son reveladas mediante los cambios en fertilidad y fecundidad del insecto. Se realizaron nueve alternancias, en cada una se suministraron dos alimentaciones, en unas se alternó la fuente de alimentación y en los controles se suministraron dos alimentaciones con la misma fuente. Las fuentes alimentarias fueron paloma, gallina y humano, esta última mediante un aparato de alimentación artificial; estas fuentes se escogieron en el supuesto que son fuentes alimentarias encontradas en los ecotopos silvestre, peri-domicilio y domicilio respectivamente. En todos los tipos de alternancia se encontró una relación lineal entre la fecundidad y el tiempo de oviposición, que la relación entre cantidad de sangre ingerida y la fecundidad varían, que la tasa de fecundidad aumenta en la segunda alimentación respecto a la primera y que la fertilidad fue superior al 95 %. Effects of alternating blood sources on fecundity and fertility of Rhodnius prolixus Stal (Heteroptera: ReduviidaeIn this work it is argued that if the reproductive parameters of Rhodnius prolixus Stal are related to the blood source upon which it feeds, then the insects biological needs must be satisfied in different ways by the alternation between blood sources, reveled through changes in the fecundity and fertility of individuals of this insect species. Nine experiments were conducted, each one consisting of two feedings, in which the blood source were either alternated or remained the same. The meal sources used were pigeon, hen and human blood, selected according to the resources found in the sylvatic, peri-domestic and domestic ecotopes respectively. It was found that the quantity of

  3. The ACBP gene family in Rhodnius prolixus

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    Majerowicz, David; Hannibal-Bach, Hans K; Castro, Rodolfo S C

    2016-01-01

    The acyl-CoA-binding proteins (ACBP) constitute a family of conserved proteins that bind acyl-CoA with high affinity and protect it from hydrolysis. Thus, ACBPs may have essential roles in basal cellular lipid metabolism. The genome of the insect Rhodnius prolixus encodes five ACBP genes similar...

  4. Metabolism and gas exchange patterns in Rhodnius prolixus.

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    Schilman, Pablo E

    Insect's metabolic rate and patterns of gas-exchange varies according to different factors such as: species, activity, mass, and temperature among others. One particular striking pattern of gas-exchange in insects is discontinuous gas-exchange cycles, for which many different hypotheses regarding their evolution have been stated. This article does not pretend to be an extensive review on the subject, rather to focus on the work performed on the haematophagous bug Rhodnius prolixus, a model organism used from the mid XX century until present days, with the great influence of Wigglesworth and his students/collaborator's work. I have no doubt that the renovated field of insect gas-exchange has a bright future and will advance at large gaits thank to the help of this model organism, R. prolixus, whose entire genome has recently being unraveled. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Effects of azadirachtin in Rhodnius prolixus: data and hypotheses

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    E. S. Garcia

    1991-01-01

    Full Text Available The effects of azadirachtin A, a tetranortriterpenoid from the neem tree Azadirachta indica J., on both development and interaction between Trypanosoma cruzi, the causative agent of Chagas' disease, and its vector Rhodnius prolixus were studied. Given through a blood meal, a dose-rsponse relationship of azadirachtin was established using antifeedant effect and ecdysis inhibition as effective parameters. A singlo dose of azadirachtin A was able to block the onset of mitosis in the epidermis and ecdysteroid titers in the hemnolymph, determined by radioimmuneassay, were too low for an induction of ecadysis. The survival of T. cruzi was also studied in R. prolixus treated with the drug. If the trypomastigotes were fed in presence of azadirachtin A the number of parasites drastically decreased. If the drug was applied after infection of the bug with T. cruzi, the parasite was still abolished from the gut. If the insect was pretreated with azadirachtin A before infection the same observation was obtained. A single dose of azadirachtin A was enough for a permanent resistance of the insect host against its reinfection with T. cruzi and for blocking the ecdysis for a long time. The effects of azadirachtin A on the hormonal balance of the host and growth inhibition of the parasite will be discussed on the basis of the present results.

  6. Functional anatomy of vagina muscles in the blood-feeding insect, Rhodnius prolixus.

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    Chiang, R G; O'Donnell, M J

    2009-11-01

    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. The lateral muscles extend from a medially-located apodeme on the posterior edge of sternite VI around each side of the common oviduct to travel posteriorly along the side of the vagina before inserting laterally on apodemes on sternite VIII. The vagina muscles display spontaneous and neurally-evoked contractions that are prolonged but transient. The response to evoked contractions shows that the muscles are innervated by both excitatory and inhibitory motor axons. The degree of tension generated by evoked contractions is dependent on the frequency of stimulation with maximal tension being generated at 20-30Hz. This tension, which often exceeds 400mg, is transient and returns to a baseline within 1 to 2min during continuous stimulation. These results, which are the first to describe this chamber in this well-studied insect, are discussed with respect to the act of egg laying.

  7. Unsaturated Glycerophospholipids Mediate Heme Crystallization: Biological Implications for Hemozoin Formation in the Kissing Bug Rhodnius prolixus

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    Stiebler, R.; Majerowicz, David; Knudsen, Jens

    2014-01-01

    Hemozoin (Hz) is a heme crystal produced by some blood-feeding organisms, as an efficient way to detoxify heme derived from hemoglobin digestion. In the triatomine insect Rhodnius prolixus, Hz is essentially produced by midgut extracellular phospholipid membranes known as perimicrovillar membrane...

  8. Glycogen Synthase Kinase-3 is involved in glycogen metabolism control and embryogenesis of Rhodnius prolixus.

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    Mury, Flávia B; Lugon, Magda D; DA Fonseca, Rodrigo Nunes; Silva, Jose R; Berni, Mateus; Araujo, Helena M; Fontenele, Marcio Ribeiro; Abreu, Leonardo Araujo DE; Dansa, Marílvia; Braz, Glória; Masuda, Hatisaburo; Logullo, Carlos

    2016-10-01

    Rhodnius prolixus is a blood-feeding insect that transmits Trypanosoma cruzi and Trypanosoma rangeli to vertebrate hosts. Rhodnius prolixus is also a classical model in insect physiology, and the recent availability of R. prolixus genome has opened new avenues on triatomine research. Glycogen synthase kinase 3 (GSK-3) is classically described as a key enzyme involved in glycogen metabolism, also acting as a downstream component of the Wnt pathway during embryogenesis. GSK-3 has been shown to be highly conserved among several organisms, mainly in the catalytic domain region. Meanwhile, the role of GSK-3 during R. prolixus embryogenesis or glycogen metabolism has not been investigated. Here we show that chemical inhibition of GSK-3 by alsterpaullone, an ATP-competitive inhibitor of GSK3, does not affect adult survival rate, though it alters oviposition and egg hatching. Specific GSK-3 gene silencing by dsRNA injection in adult females showed a similar phenotype. Furthermore, bright field and 4'-6-diamidino-2-phenylindole (DAPI) staining analysis revealed that ovaries and eggs from dsGSK-3 injected females exhibited specific morphological defects. We also demonstrate that glycogen content was inversely related to activity and transcription levels of GSK-3 during embryogenesis. Lastly, after GSK-3 knockdown, we observed changes in the expression of the Wingless (Wnt) downstream target β-catenin as well as in members of other pathways such as the receptor Notch. Taken together, our results show that GSK-3 regulation is essential for R. prolixus oogenesis and embryogenesis.

  9. Effects of precocene and azadirachtin in Rhodnius prolixus: some data on development and reproduction

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    Eloi S. Garcia

    1987-01-01

    Full Text Available The results presented in this paper clearly indicate that precocene and azadirachtin are effective inhibitors of moulting and reproduction in the hemipteran Rhodnius prolixus. The time of application is important and only applications of these substances early in the intermoulting period cause their effects in nymphs. The inhibition of moulting is fully reversed by ecdysone therapy. Precocene and azadirachtin also affected drastically the oogenesis and egg deposition in this insect. Precocene-induced sterilization is reversed by application of juvenile hormone III. However, this hormone is unable to reverse the effect of azadirachtin on reproduction. Ecdysteroid titers in nymphs and adult females are decreased by these treatments. In vitro analysis suggest that precocene and azadirachtin may act directly on the prothoracic glands and ovaries producing ecdysteroids. Based on these and other findings the possible mode of action of these compounds on the development and reproduction of Rhodnius prolixus is discussed.

  10. Experimental Infection of Rhodnius prolixus (Hemiptera, Triatominae with Mycobacterium leprae Indicates Potential for Leprosy Transmission.

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    Arthur da Silva Neumann

    Full Text Available Leprosy is a chronic dermato-neurological disease caused by infection with Mycobacterium leprae. In 2013 almost 200,000 new cases of leprosy were detected around the world. Since the first symptoms take from years to decades to appear, the total number of asymptomatic patients is impossible to predict. Although leprosy is one of the oldest records of human disease, the mechanisms involved with its transmission and epidemiology are still not completely understood. In the present work, we experimentally investigated the hypothesis that the mosquitoes Aedes aegypti and Culex quinquefasciatus and the hemiptera Rhodnius prolixus act as leprosy vectors. By means of real-time PCR quantification of M. leprae 16SrRNA, we found that M. leprae remained viable inside the digestive tract of Rhodnius prolixus for 20 days after oral infection. In contrast, in the gut of both mosquito species tested, we were not able to detect M. leprae RNA after a similar period of time. Inside the kissing bug Rhodnius prolixus digestive tract, M. leprae was initially restricted to the anterior midgut, but gradually moved towards the hindgut, in a time course reminiscent of the life cycle of Trypanosoma cruzi, a well-known pathogen transmitted by this insect. The maintenance of M. leprae infectivity inside the digestive tract of this kissing bug is further supported by successful mice footpad inoculation with feces collected 20 days after infection. We conclude that Rhodnius prolixus defecate infective M. leprae, justifying the evaluation of the presence of M. leprae among sylvatic and domestic kissing bugs in countries endemic for leprosy.

  11. Experimental Infection of Rhodnius prolixus (Hemiptera, Triatominae) with Mycobacterium leprae Indicates Potential for Leprosy Transmission.

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    Neumann, Arthur da Silva; Dias, Felipe de Almeida; Ferreira, Jéssica da Silva; Fontes, Amanda Nogueira Brum; Rosa, Patricia Sammarco; Macedo, Rafael Enrique; Oliveira, José Henrique; Teixeira, Raquel Lima de Figueiredo; Pessolani, Maria Cristina Vidal; Moraes, Milton Ozório; Suffys, Philip Noel; Oliveira, Pedro L; Sorgine, Marcos Henrique Ferreira; Lara, Flavio Alves

    2016-01-01

    Leprosy is a chronic dermato-neurological disease caused by infection with Mycobacterium leprae. In 2013 almost 200,000 new cases of leprosy were detected around the world. Since the first symptoms take from years to decades to appear, the total number of asymptomatic patients is impossible to predict. Although leprosy is one of the oldest records of human disease, the mechanisms involved with its transmission and epidemiology are still not completely understood. In the present work, we experimentally investigated the hypothesis that the mosquitoes Aedes aegypti and Culex quinquefasciatus and the hemiptera Rhodnius prolixus act as leprosy vectors. By means of real-time PCR quantification of M. leprae 16SrRNA, we found that M. leprae remained viable inside the digestive tract of Rhodnius prolixus for 20 days after oral infection. In contrast, in the gut of both mosquito species tested, we were not able to detect M. leprae RNA after a similar period of time. Inside the kissing bug Rhodnius prolixus digestive tract, M. leprae was initially restricted to the anterior midgut, but gradually moved towards the hindgut, in a time course reminiscent of the life cycle of Trypanosoma cruzi, a well-known pathogen transmitted by this insect. The maintenance of M. leprae infectivity inside the digestive tract of this kissing bug is further supported by successful mice footpad inoculation with feces collected 20 days after infection. We conclude that Rhodnius prolixus defecate infective M. leprae, justifying the evaluation of the presence of M. leprae among sylvatic and domestic kissing bugs in countries endemic for leprosy.

  12. Analysis of antenal sensilla patterns of Rhodnius prolixus from Colombia and Venezuela

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    Lyda Esteban

    2005-12-01

    Full Text Available Antennal sensilla patterns were used to analyze population variation of domestic Rhodnius prolixus from six departments and states representing three biogeographical regions of Colombia and Venezuela. Discriminant analysis of the patterns of mechanoreceptors and of three types of chemoreceptors on the pedicel and flagellar segments showed clear differentiation between R. prolixus populations east and west of the Andean Cordillera. The distribution of thick and thin-walled trichoids on the second flagellar segment also showed correlation with latitude, but this was not seen in the patterns of other sensilla. The results of the sensilla patterns appear to be reflecting biogeographic features or population isolation rather than characters associated with different habitats and lend support to the idea that domestic R. prolixus originated in the eastern region of the Andes.

  13. Phase contrast X-ray synchrotron imaging for assessing external and internal morphology of Rhodnius prolixus

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    Almeida, Andre P. de, E-mail: apalmeid@gmail.com [Physics Institute, State University of Rio de Janeiro (Brazil); Nuclear Engineering Program, COPPE, Federal University of Rio de Janeiro (Brazil); Soares, Jose [Physics Institute, State University of Rio de Janeiro (Brazil); Meneses, Anderson A.M. [Radiological Sciences Laboratory, State University of Rio de Janeiro (Brazil); Federal University of Western Para (Brazil); Cardoso, Simone C. [Physics Institute, Federal University of Rio de Janeiro (Brazil); Braz, Delson [Nuclear Engineering Program, COPPE, Federal University of Rio de Janeiro (Brazil); Garcia, Eloi S. [Laboratory of Biochemistry and Physiology of Insects, Oswaldo Cruz Institute, FIOCRUZ (Brazil); Gonzalez, Marcelo S. [Department of General Biology, Federal University Fluminense (Brazil); Azambuja, Patricia [Laboratory of Biochemistry and Physiology of Insects, Oswaldo Cruz Institute, FIOCRUZ (Brazil); Barroso, Regina C. [Physics Institute, State University of Rio de Janeiro (Brazil)

    2012-07-15

    PhC-SR-{mu}CT is a nondestructive technique that allows the microanatomical investigations and 3D images reconstructions. This technique is performed in blood sucker, Rhodnius prolixus-one of the most important insect vectors of Trypanosoma cruzi, ethiologic agent of Chagas' disease in Latin America-was able to provide excellent information about the microanatomy of the thorax and head allowing a new tool for further studies of development and physiology of triatomine by a non-invasive method of observation. - Highlights: Black-Right-Pointing-Pointer In this work we used SR-PhC-{mu}CT to study the microanatomy of R. prolixus. Black-Right-Pointing-Pointer We investigate SR-PhC-{mu}CT to the 3D reconstruction of internal structures. Black-Right-Pointing-Pointer We get information about the tissues responsible for the development of the insect.

  14. Mariner transposons are sailing in the genome of the blood-sucking bug Rhodnius prolixus.

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    Filée, Jonathan; Rouault, Jacques-Deric; Harry, Myriam; Hua-Van, Aurélie

    2015-12-15

    The Triatomine bug Rhodnius prolixus is a vector of Trypanosoma cruzi, which causes the Chagas disease in Latin America. R. prolixus can also transfer transposable elements horizontally across a wide range of species. We have taken advantage of the availability of the 700 Mbp complete genome sequence of R. prolixus to study the dynamics of invasion and persistence of transposable elements in this species. Using both library-based and de novo methods of transposon detection, we found less than 6 % of transposable elements in the R. prolixus genome, a relatively low percentage compared to other insect genomes with a similar genome size. DNA transposons are surprisingly abundant and elements belonging to the mariner family are by far the most preponderant components of the mobile part of this genome with 11,015 mariner transposons that could be clustered in 89 groups (75 % of the mobilome). Our analysis allowed the detection of a new mariner clade in the R. prolixus genome, that we called nosferatis. We demonstrated that a large diversity of mariner elements invaded the genome and expanded successfully over time via three main processes. (i) several families experienced recent and massive expansion, for example an explosive burst of a single mariner family led to the generation of more than 8000 copies. These recent expansion events explain the unusual prevalence of mariner transposons in the R. prolixus genome. Other families expanded via older bursts of transposition demonstrating the long lasting permissibility of mariner transposons in the R. prolixus genome. (ii) Many non-autonomous families generated by internal deletions were also identified. Interestingly, two non autonomous families were generated by atypical recombinations (5' part replacement with 3' part). (iii) at least 10 cases of horizontal transfers were found, supporting the idea that host/vector relationships played a pivotal role in the transmission and subsequent persistence of transposable

  15. Perimicrovillar membrane assembly: the fate of phospholipids synthesised by the midgut of Rhodnius prolixus

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    Paula Rego Bittencourt-Cunha

    2013-06-01

    Full Text Available In this study, we describe the fate of fatty acids that are incorporated from the lumen by the posterior midgut epithelium of Rhodnius prolixus and the biosynthesis of lipids. We also demonstrate that neutral lipids (NL are transferred to the haemolymphatic lipophorin (Lp and that phospholipids remain in the tissue in which they are organised into perimicrovillar membranes (PMMs. 3H-palmitic acid added at the luminal side of isolated midguts of R. prolixus females was readily absorbed and was used to synthesise phospholipids (80% and NL (20%. The highest incorporation of 3H-palmitic acid was on the first day after a blood meal. The amounts of diacylglycerol (DG and triacylglycerol synthesised by the tissue decreased in the presence of Lp in the incubation medium. The metabolic fates of 3H-lipids synthesised by the posterior midgut were followed and it was observed that DG was the major lipid released to Lp particles. However, the majority of phospholipids were not transferred to Lp, but remained in the tissue. The phospholipids that were synthesised and accumulated in the posterior midgut were found to be associated with Rhodnius luminal contents as structural components of PMMs.

  16. Effects of azadirachtin on Rhodnius prolixus: immunity and trypanosoma interaction

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    Patricia de Azambuja

    1992-01-01

    Full Text Available The effects of azadirachtin, a tetranortriterpenoid from the neem tree Aradirachta indica J. on both immunity and Trypanosoma cruzi interaction within Rhodniusprolixus and other triatomines, were presented Given through a blood meal, azadirachtin affected the immune reactivity as shown by a significant reduction in numbers of hemocytes and consequently nodule formation follwing challenge with Enterobacter cloacae ß12, reduction in ability to produce antibacterial activities in the hemolymph when injected with bacteria, and decreased ability to destroy the infection caused by inoculation of E. cloacae cells. A single dose of azadirachtin was able to block the development of T. cruzi in R. prolixus if given through the meal at different intervals, together with, before or after parasite infection. Similary, these results were observed with different triatomine species and different strains of T. cruzi. Azadirachtin induced a permanent resistance of the vector against reinfection with T. cruzi. The significance of these data is discussed in relation to the general mode of azadirachtin action in insects.

  17. The proctolin gene and biological effects of proctolin in the blood-feeding bug, Rhodnius prolixus.

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    Ian eOrchard

    2011-10-01

    Full Text Available We have reinvestigated the possible presence or absence of the pentapeptide proctolin in Rhodnius prolixus and report here the cloning of the proctolin cDNA. The transcript is highly expressed in the central nervous system (CNS with some low expression associated with peripheral tissues. The proctolin prepropeptide encodes a single copy of proctolin along with a proctolin-precursor-associated peptide. We have biochemically identified proctolin in CNS extracts and shown its distribution using proctolin-like immunoreactivity. Immunostained processes are found on the salivary glands, female and male reproductive organs, and heart and associated alary muscles. Proctolin-like immunoreactive bipolar neurons are found on the lateral margins of the common oviduct and bursa. Proctolin is biologically active on R. prolixus tissues, stimulating increases in contraction of anterior midgut and hindgut muscles, and increasing heartbeat frequency. Contrary to the previous suggestion that proctolin is absent from R. prolixus, proctolin is indeed present and biologically active in this medically-important bug.

  18. Activity and Residual Effect of Two Formulations of Lambdacyhalothrin Sprayed on Palm Leaves to Rhodnius prolixus

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    Mazariego-Arana Miguel Angel

    2002-01-01

    Full Text Available The insecticidal activity and residual effect of two formulations of lambdacyhalothrin were evaluated with Rhodnius prolixus;laboratory and field tests were conducted in the State of Chiapas, Mexico. The results indicate that the lethal concentrations of the active ingredient of SC (LC50 = 2.37 and LC90 = 8.5 mg, a.i./m² were 4-8 times than those with the insecticide WP applied on R. prolixus bugs in palm leaves, a common building material for thatched roofs. Other investigators in South America recommended applying 30 mg a.i./m² in porous materials; we obtained that the products WP and SC were 3.5 and 16 times more effective on palm leaves. Regarding the evaluation of the residual effects in field spraying, there was up to 15 months persistence after the application of WP in two doses (8.6 mg a.i./m² and 3.752 mg a.i./m² with SC. We consider R. prolixus highly susceptible to the employed pyrethroids; they could be used to control this vector in the state of Chiapas, Mexico.

  19. Rhodnius prolixus supergene families of enzymes potentially associated with insecticide resistance.

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    Schama, Renata; Pedrini, Nicolás; Juárez, M Patricia; Nelson, David R; Torres, André Q; Valle, Denise; Mesquita, Rafael D

    2016-02-01

    Chagas disease or American trypanosomiasis, is a potentially life-threatening illness caused by the protozoan parasite, Trypanosoma cruzi. Once known as an endemic health problem of poor rural populations in Latin American countries, it has now spread worldwide. The parasite is transmitted by triatomine bugs, of which Rhodnius prolixus (Hemiptera, Reduviidae, Triatominae) is one of the vectors and a model organism. This species occurs mainly in Central and South American countries where the disease is endemic. Disease prevention focuses on vector control programs that, in general, rely intensely on insecticide use. However, the massive use of chemical insecticides can lead to resistance. One of the major mechanisms is known as metabolic resistance that is associated with an increase in the expression or activity of detoxification genes. Three of the enzyme families that are involved in this process - carboxylesterases (CCE), glutathione s-transferases (GST) and cytochrome P450s (CYP) - are analyzed in the R. prolixus genome. A similar set of detoxification genes to those of the Hemipteran Acyrthosiphon pisum but smaller than in most dipteran species was found in R. prolixus genome. All major CCE classes (43 genes found) are present but the pheromone/hormone processing class had fewer genes than usual. One main expansion was detected on the detoxification/dietary class. The phosphotriesterase family, recently associated with insecticide resistance, was also represented with one gene. One microsomal GST gene was found and the cytosolic GST gene count (14 genes) is extremely low when compared to the other hemipteran species with sequenced genomes. However, this is similar to Apis mellifera, a species known for its deficit in detoxification genes. In R. prolixus 88 CYP genes were found, with representatives in the four clans (CYP2, CYP3, CYP4 and mitochondrial) usually found in insects. R. prolixus seems to have smaller species-specific expansions of CYP genes than

  20. Changes associated with laboratory rearing in antennal sensilla patterns of Triatoma infestans, Rhodnius prolixus, and Rhodnius pallescens (Hemiptera, Reduviidae, Triatominae

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    Catalá SS

    2004-01-01

    Full Text Available We examined changes in the array of antennal sensilla of three species of Triatominae (Triatoma infestans, Rhodnius prolixus, and R. pallescens following their establishment for different periods in laboratory culture. In each case, the laboratory colonies were compared with conspecific samples taken directly from the field, by quantitative analysis of the sensilla arrays on the three distal segments of the antenna in terms of the densities of three types of chemoreceptors (basiconics and thick and thin walled trichoids and one type of mechanoreceptor (bristles. Sensilla densities were compared by ANOVA or non-parametric tests, and by multivariate discriminant analysis. Strains of the same species reared in different laboratories showed significant differences in their sensilla arrays, especially when compared to field-collected material from the same geographic origin. A Bolivian strain of T. infestans reared in the laboratory for 15 years and fed at monthly intervals, showed greatest differences from its conspecific wild forms, especially in terms of reductions in the number of chemoreceptors. By contrast, an Argentine strain of T. infestans reared for 25 years in the laboratory and fed weekly, showed a relative increase in the density of mechanoreceptors. A Colombian strain of R. prolixus reared for 20 years and fed weekly or fortnightly, showed only modest differences in the sensilla array when compared to its wild populations from the same area. However, a Colombian strain of R. pallescens reared for 12 years and fed fortnightly, did show highly significant reductions in one form of chemoreceptor compared to its conspecific wild populations. For all populations, multivariate analysis clearly discriminated between laboratory and field collected specimens, suggesting that artificial rearing can lead to modifications in the sensory array. This not only supports the idea of morphological plasticity in these species, but also suggests caution in

  1. Effects of juvenile hormone analogue on ecdysis prevention induced by precocene in Rhodnius prolixus (Hemiptera: Reduviidae

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    Patricia de Azambuja

    1984-12-01

    Full Text Available Precocene II, added to the meal of fourth-instar larvae of Rhodnius prolixus (25 mug/ml of blood, induced an in crease 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 mug/insect together with Precocene II treatment avoided atrophy of the prothoracic glands and induced a higher number of epidermal mitosis accelerating the time of subsequent ecdysis. A possible relationship between juvenile hormone and production of ecdysone is discussed.Adicionado ao sangue alimentar na dose de 25 mug/ml o precoceno II causou um aumento no período de intermuda em ninfas de 4o. estadio de Rhodnius prolixus. Este atraso da muda foi relacionado com a diminuição da área dos núcleos das celulas das glandulas protoracicas e com a queda da atividade mitotica das células da epiderme do inseto. Um análogo de hormônio juvenil aplicado topicamente (60 mug/inseto junto com o tratamento oral com precoceno II preveniu a atrofia das glândulas protorácicas e induziu um aumento no número de mitoses nas células da epiderme, diminuindo o período de intermuda nestes insetos.A possivel relação entre a ação do hormônio juvenil e a producao de ecdisona pelas glândulas protorácicas e discutida.

  2. Unsaturated glycerophospholipids mediate heme crystallization: biological implications for hemozoin formation in the kissing bug Rhodnius prolixus.

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    Renata Stiebler

    Full Text Available Hemozoin (Hz is a heme crystal produced by some blood-feeding organisms, as an efficient way to detoxify heme derived from hemoglobin digestion. In the triatomine insect Rhodnius prolixus, Hz is essentially produced by midgut extracellular phospholipid membranes known as perimicrovillar membranes (PMVM. Here, we investigated the role of commercial glycerophospholipids containing serine, choline and ethanolamine as headgroups and R. prolixus midgut lipids (RML in heme crystallization. All commercial unsaturated forms of phospholipids, as well as RML, mediated fast and efficient β-hematin formation by means of two kinetically distinct mechanisms: an early and fast component, followed by a late and slow one. The fastest reactions observed were induced by unsaturated forms of phosphatidylethanolamine (uPE and phosphatidylcholine (uPC, with half-lives of 0.04 and 0.7 minutes, respectively. β-hematin crystal morphologies were strikingly distinct among groups, with uPE producing homogeneous regular brick-shaped crystals. Interestingly, uPC-mediated reactions resulted in two morphologically distinct crystal populations: one less representative group of regular crystals, resembling those induced by uPE, and the other largely represented by crystals with numerous sharp edges and tapered ends. Heme crystallization reactions induced by RML were efficient, with a heme to β-hematin conversion rate higher than 70%, but clearly slower (t1/2 of 9.9-17.7 minutes than those induced by uPC and uPE. Interestingly, crystals produced by RML were homogeneous in shape and quite similar to those mediated by uPE. Thus, β-hematin formation can be rapidly and efficiently induced by unsaturated glycerophospholipids, particularly uPE and uPC, and may play a role on biological heme crystallization in R. prolixus midgut.

  3. Comparative Analysis of Repetitive DNA between the Main Vectors of Chagas Disease: Triatoma infestans and Rhodnius prolixus.

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    Pita, Sebastián; Mora, Pablo; Vela, Jesús; Palomeque, Teresa; Sánchez, Antonio; Panzera, Francisco; Lorite, Pedro

    2018-04-24

    Chagas disease or American trypanosomiasis affects six to seven million people worldwide, mostly in Latin America. This disease is transmitted by hematophagous insects known as "kissing bugs" (Hemiptera, Triatominae), with Triatoma infestans and Rhodnius prolixus being the two most important vector species. Despite the fact that both species present the same diploid chromosome number (2 n = 22), they have remarkable differences in their total DNA content, chromosome structure and genome organization. Variations in the DNA genome size are expected to be due to differences in the amount of repetitive DNA sequences. The T. infestans genome-wide analysis revealed the existence of 42 satellite DNA families. BLAST searches of these sequences against the R. prolixus genome assembly revealed that only four of these satellite DNA families are shared between both species, suggesting a great differentiation between the Triatoma and Rhodnius genomes. Fluorescence in situ hybridization (FISH) location of these repetitive DNAs in both species showed that they are dispersed on the euchromatic regions of all autosomes and the X chromosome. Regarding the Y chromosome, these common satellite DNAs are absent in T. infestans but they are present in the R. prolixus Y chromosome. These results support a different origin and/or evolution in the Y chromosome of both species.

  4. Trypanosoma cruzi: effects of azadirachtin and ecdysone on the dynamic development in Rhodnius prolixus larvae.

    Science.gov (United States)

    Cortez, M R; Provençano, A; Silva, C E; Mello, C B; Zimmermann, L T; Schaub, G A; Garcia, E S; Azambuja, P; Gonzalez, M S

    2012-07-01

    The effects of azadirachtin and ecdysone on the Trypanosoma cruzi population in the Rhodnius prolixus gut were investigated. T. cruzi were rarely found in the gut compartments of azadirachtin-treated larvae. High parasite numbers were observed in the stomach of the control and ecdysone groups until 10 days after treatment and in the small intestine and rectum until 25 days after treatment. High percentages of round forms developed in the stomachs of all groups, whereas azadirachtin blocked the development of protozoan intermediate forms. This effect was counteracted by ecdysone therapy. In the small intestine and rectum, epimastigotes predominated for all groups, but more of their intermediates developed in the control and ecdysone groups. Azadirachtin supported the development of round forms and their intermediates into trypomastigotes. In the rectum, trypomastigotes did not develop in the azadirachtin group and developed much later after ecdysone therapy. The parallel between the effects of azadirachtin and ecdysone on the host and parasite development is discussed on the basis of the present results because ecdysone appears to act directly or indirectly in determining the synchronic development of T. cruzi forms from round to epimastigotes, but not metacyclic trypomastigotes, in the invertebrate vector. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. A resposta de Rhodnius prolixus a estímulos térmicos

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    Terezinha Fujita

    1976-06-01

    Full Text Available Uma série de experiências com formas adultas de Rhodnius prolixus, realizadas tanto no laboratório como em recinto de dimensões mais amplas, demonstrou uma acentuada atração para fontes de calor, com um máximo de atividades em torno dos 37 graus Centígrados. Nossos estudos revelaram que o inseto percebe estímulos térmicos a uma certa distância da fonte. Embora o reconhecimento de radiações infra-vermelhas possa servir para uma orientação do triatomíneo em direção ao animal de sangue quente, não acreditamos que seja o único fator envolvido. Com a continuação de pesquisas deste gênero visa-se o aperfeiçoamento de uma técnica que se preste para o combate ao vetor.

  6. Effects of the essential oil obtained from Pilocarpus spicatus Saint-Hilaire (Rutaceae on the development of Rhodnius prolixus nymphae

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    Cícero B. Mello

    Full Text Available Bioassays against fifth-instar nymphae of Rhodnius prolixus were conducted with essential oil of Pilocarpus spicatus extracted by hydrodistillation. The main results may be summarized as follows: (i high levels of toxicity and paralysis together with discrete moulting inhibition were caused by topical application of either 0.5 µL or 1.0 µL per insect of the crude essential oil; (ii partial fagoinhibition, high moulting inhibition, prolonged intermoulting period and high number of paralyzed insects, but no toxicity were observed after oral treatment using either 5 µL or 10 µL of Pilocarpus spilcatus essential oil per mL of ingested blood meal. The importance of these results in relation to the relevant biological events in R. prolixus is herein discussed.

  7. Environmental variables, remote sensing and geographical information systems applied to the study of Rhodnius prolixus distribution in Colombia

    International Nuclear Information System (INIS)

    Guhl, Felipe

    2010-01-01

    A data base of the entomological survey performer during the Chagas Disease National Control Programme (CHDNCP) in 1997 - 2001 and temporal satellite images masp containing 57 environmental variables were used to build Rhodnius prolixus dispersion predictive maps in Colombia, based on temporal images, Fourier analyses and a discriminative multivaried statistical analyses of the variables studied. The maps show the dispersion of this species and its implication on the Chagas disease transmission in Colombia. A clear division in the predictive dispersion of R. prolixus in two geographical zones was found: one area in the southeast of the Eastern Cordillera associated with the environmental variables used in the present study and a second zone in the Andean Valleys, East of the Eastern Cordillera not much defined by the same variables. This would suggest that the Southwest Region. of Colombia presents a tendency to a wider dispersion of R. prolixus associated to other variables like human intervention. Sylvatic populations of R. prolixus were found recently in Attalea butyracea palm trees in this Region of the Eastern Planes demonstrating the prediction of the presence of this species.

  8. Modeling horizontal gene transfer (HGT in the gut of the Chagas disease vector Rhodnius prolixus

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    Durvasula Ravi V

    2011-05-01

    Full Text Available Abstract Background Paratransgenesis is an approach to reducing arthropod vector competence using genetically modified symbionts. When applied to control of Chagas disease, the symbiont bacterium Rhodococcus rhodnii, resident in the gut lumen of the triatomine vector Rhodnius prolixus (Hemiptera: Reduviidae, is transformed to export cecropin A, an insect immune peptide. Cecropin A is active against Trypanosoma cruzi, the causative agent of Chagas disease. While proof of concept has been achieved in laboratory studies, a rigorous and comprehensive risk assessment is required prior to consideration of field release. An important part of this assessment involves estimating probability of transgene horizontal transfer to environmental organisms (HGT. This article presents a two-part risk assessment methodology: a theoretical model predicting HGT in the gut of R. prolixus from the genetically transformed symbiont R. rhodnii to a closely related non-target bacterium, Gordona rubropertinctus, in the absence of selection pressure, and a series of laboratory trials designed to test the model. Results The model predicted an HGT frequency of less than 1.14 × 10-16 per 100,000 generations at the 99% certainty level. The model was iterated twenty times, with the mean of the ten highest outputs evaluated at the 99% certainty level. Laboratory trials indicated no horizontal gene transfer, supporting the conclusions of the model. Conclusions The model treats HGT as a composite event, the probability of which is determined by the joint probability of three independent events: gene transfer through the modalities of transformation, transduction, and conjugation. Genes are represented in matrices and Monte Carlo method and Markov chain analysis are used to simulate and evaluate environmental conditions. The model is intended as a risk assessment instrument and predicts HGT frequency of less than 1.14 × 10-16 per 100,000 generations. With laboratory studies that

  9. Acidocalcisomes as calcium- and polyphosphate-storage compartments during embryogenesis of the insect Rhodnius prolixus Stahl.

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    Isabela Ramos

    Full Text Available BACKGROUND: The yolk of insect eggs is a cellular domain specialized in the storage of reserve components for embryo development. The reserve macromolecules are stored in different organelles and their interactions with the embryo cells are mostly unknown. Acidocalcisomes are lysosome-related organelles characterized by their acidic nature, high electron density and large content of polyphosphate bound to several cations. In this work, we report the presence of acidocalcisome-like organelles in eggs of the insect vector Rhodnius prolixus. METHODOLOGY/PRINCIPAL FINDINGS: Characterization of the elemental composition of electron-dense vesicles by electron probe X-ray microanalysis revealed a composition similar to that previously described for acidocalcisomes. Following subcellular fractionation experiments, fractions enriched in acidocalcisomes were obtained and characterized. Immunofluorescence showed that polyphosphate polymers and the vacuolar proton translocating pyrophosphatase (V-H(+-PPase, considered as a marker for acidocalcisomes are found in the same vesicles and that these organelles are mainly localized in the egg cortex. Polyphosphate quantification showed that acidocalcisomes contain a significant amount of polyphosphate detected at day-0 eggs. Elemental analyses of the egg fractions showed that 24.5±0.65% of the egg calcium are also stored in such organelles. During embryogenesis, incubation of acidocalcisomes with acridine orange showed that these organelles are acidified at day-3 (coinciding with the period of yolk mobilization and polyphosphate quantification showed that the levels of polyphosphate tend to decrease during early embryogenesis, being approximately 30% lower at day-3 compared to day-0 eggs. CONCLUSIONS: We found that acidocalcisomes are present in the eggs and are the main storage compartments of polyphosphate and calcium in the egg yolk. As such components have been shown to be involved in a series of dynamic

  10. Nuevos aspectos del método de xenodiagnóstico con Rhodnius prolixus

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    Ernesto Osorno Mesa

    1963-04-01

    Full Text Available The efficiency of Xenodiagnostico is noted, as a biological method of making an etiological diagnosis of Chagas disease, It is pointed out that the fourth and fifth nymph stages are the most appropriate, not only because of the great amount of blood which they ingurgitate to repletion, but also because of the facility of the routine operations without the necessity of extraeting and placing the specimens in receptacles of superficial cleanliness in order to separate the full specimens from the empty ones. The advantages of a partial diet of blood is indicated in order to prevent the nymphs from becoming adults. The technique used in the study of spontaneous dejection in Rhodnius prolixus experimentally infected is described and the advantages noted. The article describes an original method "Dejectograma" of recording the total digestion of blood during one month in normal and infected fifth stage nymphs. The recording apparatus is an adapted thermograph which we call a "Dejectografo". Some observations are made concerning the discovery of evolved forms of S. cruzi, in several spontaneous dejections and the survival of metacyclic forms in hyaline for 30 hours between the slide and cover slide at a temperature of 150 C. Attention is called to the intermission of ejection of evolved forms of S. cruzi, with the conclusion that in order to avoid false negative results, dissection of the digestive tracts is necessary in these cases. The possibility of complete studies is set forth, aided by the techniques explained, and along the lines of the few observations made from pilot experiments.

  11. Jaburetox-induced toxic effects on the hemocytes of Rhodnius prolixus (Hemiptera: Reduviidae).

    Science.gov (United States)

    Moyetta, Natalia R; Broll, Valquiria; Perin, Ana Paula A; Uberti, Augusto F; Coste Grahl, Matheus V; Staniscuaski, Fernanda; Carlini, Celia R; Fruttero, Leonardo L

    2017-10-01

    Jaburetox is a recombinant peptide derived from a Canavalia ensiformis urease that presents toxic effects upon several species of insects, phytopathogenic fungi and yeasts of medical importance. So far, no toxicity of Jaburetox to mammals has been shown. Previous reports have identified biochemical targets of this toxic peptide in insect models, although its mechanism of action is not completely understood. In this work, we aimed to characterize the effects of Jaburetox in hemolymphatic insect cells. For this purpose, the model insect and Chagas' disease vector Rhodnius prolixus was used. In vivo and in vitro experiments indicated that Jaburetox interacts with a subset of hemocytes and it can be found in various subcellular compartments. In insects injected with Jaburetox there was an increase in the gene expression of the enzymes UDP-N-acetylglucosamine pyrophosphorylase (UAP), chitin synthase and nitric oxide synthase (NOS). Nevertheless, the expression of NOS protein, the enzyme activities of UAP and acid phosphatase (a possible link between UAP and NOS) as well as the phosphorylation state of proteins remained unchanged upon the in vivo Jaburetox treatment. Nitric oxide (NO) imaging using fluorescent probes showed that Jaburetox augmented NO production in the hemocyte aggregates when compared to controls. Even though Jaburetox activated the hemocytes, as demonstrated by wheat germ agglutinin binding assays, the peptide did not lead to an increase of their phagocytic behavior. Taken together, these findings contribute to our understanding of toxic effects of Jaburetox, a peptide with biotechnological applications and a prospective tool for rational insect control. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Transcriptome and gene expression profile of ovarian follicle tissue of the triatomine bug Rhodnius prolixus

    Science.gov (United States)

    Medeiros, Marcelo N.; Logullo, Raquel; Ramos, Isabela B.; Sorgine, Marcos H. F.; Paiva-Silva, Gabriela O.; Mesquita, Rafael D.; Machado, Ednildo Alcantara; Coutinho, Maria Alice; Masuda, Hatisaburo; Capurro, Margareth L.; Ribeiro, José M.C.; Cardoso Braz, Glória Regina; Oliveira, Pedro L

    2013-01-01

    Insect oocytes grow in close association with the ovarian follicular epithelium (OFE), which escorts the oocyte during oogenesis and is responsible for synthesis and secretion of the eggshell. We describe a transcriptome of OFE of the triatomine bug Rhodnius prolixus, a vector of Chagas disease, to increase our knowledge of the role of FE in egg development. Random clones were sequenced from a cDNA library of different stages of follicle development. The transcriptome showed high commitment to transcription, protein synthesis, and secretion. The most abundant cDNA was a secreted (S) small, proline-rich protein with maximal expression in the vitellogenic follicle, suggesting a role in oocyte maturation. We also found Rp45, a chorion protein already described, and a putative chitin-associated cuticle protein that was an eggshell component candidate. Six transcripts coding for proteins related to the unfolded protein response (UPR) by were chosen and their expression analyzed. Surprisingly, transcripts related to UPR showed higher expression during early stages of development and downregulation during late stages, when transcripts coding for S proteins participating in chorion formation were highly expressed. Several transcripts with potential roles in oogenesis and embryo development are also discussed. We propose that intense protein synthesis at the FE results in reticulum stress (RS) and that lowering expression of a set of genes related to cell survival should lead to degeneration of follicular cells at oocyte maturation. This paradoxical suppression of UPR suggests that ovarian follicles may represent an interesting model for studying control of RS and cell survival in professional S cell types. PMID:21736942

  13. MDL28170, a calpain inhibitor, affects Trypanosoma cruzi metacyclogenesis, ultrastructure and attachment to Rhodnius prolixus midgut.

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    Vítor Ennes-Vidal

    Full Text Available BACKGROUND: Trypanosoma cruzi is the etiological agent of Chagas' disease. During the parasite life cycle, many molecules are involved in the differentiation process and infectivity. Peptidases are relevant for crucial steps of T. cruzi life cycle; as such, it is conceivable that they may participate in the metacyclogenesis and interaction with the invertebrate host. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we have investigated the effect of the calpain inhibitor MDL28170 on the attachment of T. cruzi epimastigotes to the luminal midgut surface of Rhodnius prolixus, as well as on the metacyclogenesis process and ultrastructure. MDL28170 treatment was capable of significantly reducing the number of bound epimastigotes to the luminal surface midgut of the insect. Once the cross-reactivity of the anti-Dm-calpain was assessed, it was possible to block calpain molecules by the antibody, leading to a significant reduction in the capacity of adhesion to the insect guts by T. cruzi. However, the antibodies were unable to interfere in metacyclogenesis, which was impaired by the calpain inhibitor presenting a significant reduction in the number of metacyclic trypomastigotes. The calpain inhibitor also promoted a direct effect against bloodstream trypomastigotes. Ultrastructural analysis of epimastigotes treated with the calpain inhibitor revealed disorganization in the reservosomes, Golgi and plasma membrane disruption. CONCLUSIONS/SIGNIFICANCE: The presence of calpain and calpain-like molecules in a wide range of organisms suggests that these proteins could be necessary for basic cellular functions. Herein, we demonstrated the effects of MDL28170 in crucial steps of the T. cruzi life cycle, such as attachment to the insect midgut and metacyclogenesis, as well as in parasite viability and morphology. Together with our previous findings, these results help to shed some light on the functions of T. cruzi calpains. Considering the potential roles of

  14. Rhodnius prolixus en Nicaragua: distribución geográfica, control y vigilancia entre 1998 y 2009 Rhodnius prolixus in Nicaragua: geographical distribution, control, and surveillance, 1998-2009

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    Kota Yoshioka

    2011-11-01

    Full Text Available OBJETIVO: Presentar la perspectiva general del control de Rhodnius prolixus, el principal vector en la transmisión de la enfermedad de Chagas en Centroamérica, durante el período 1998-2009 en Nicaragua. Describir el control vectorial realizado y presentar la distribución geográfica de las localidades infestadas. MÉTODOS: Se estudió y analizó la información disponible en el Ministerio de Salud de Nica ragua. Se visualizó la distribución geográfica de R. prolixus mediante el programa visualiza dor de mapas Quantum GIS 1.5.0. RESULTADOS: Se determinó que 59 localidades en 14 municipios de 8 departamentos presen taron antecedentes de infestación con R. prolixus entre 1998 y 2009. La altitud de las locali dades infestadas oscila entre 160 y 1 414 metros sobre el nivel del mar. Se han tratado con más de dos ciclos de control químico 56 localidades. En el segundo ciclo de rociamiento se detectó la presencia del vector, pero durante el tercer ciclo no se lo encontró en ninguna localidad. CONCLUSIONES: La mayor concentración geográfica de R. prolixus se observó en dos depar tamentos de la región norte: Madriz y Nueva Segovia. La cantidad de localidades infestadas es menor en Nicaragua que en otros países centroamericanos. El control químico ha sido exitoso en las localidades intervenidas, pero es necesario fortalecer el sistema de vigilancia institucio nal y comunitaria tanto para vigilar la reinfestación con R. prolixus como para ampliar la cobertura del control vectorialOBJECTIVE: Present an overview of the control of Rhodnius prolixus, the principal vector in the transmission of Chagas' disease in Central America, during the period 1998-2009 in Nicaragua. Describe the vector control carried out and the geographical distribution of the infested localities. METHODS: The available information in Nicaragua's Ministry of Health was studied and analyzed. The geographical distribution of R. prolixus was visualized using the Quantum

  15. In vitro and in vivo documentation of quantum dots labeled Trypanosoma cruzi--Rhodnius prolixus interaction using confocal microscopy.

    Science.gov (United States)

    Feder, Denise; Gomes, Suzete A O; de Thomaz, André A; Almeida, Diogo B; Faustino, Wagner M; Fontes, Adriana; Stahl, Cecília V; Santos-Mallet, Jacenir R; Cesar, Carlos L

    2009-12-01

    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 as lectins to label specific carbohydrates involved on the parasite-vector interaction. These QDs were successfully used for the study of in vitro and in vivo interaction of Trypanosoma cruzi and the triatomine Rhodnius prolixus. These QDs allowed us to acquire real time confocal images sequences of live T. cruzi-R. prolixus interactions for an extended period, causing no damage to the cells. By zooming to the region of interest, we have been able to acquire confocal images at the three to four frames per second rate. Our results show that QDs are physiological fluorescent markers capable to label living parasites and insect vector cells. QDs can be functionalized with lectins to specifically mark surface carbohydrates on perimicrovillar membrane of R. prolixus to follow, visualize, and understand interaction between vectors and its parasites in real-time.

  16. Identification and expression of the CCAP receptor in the Chagas' disease vector, Rhodnius prolixus, and its involvement in cardiac control.

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    Dohee Lee

    Full Text Available Rhodnius prolixus is the vector of Chagas' disease, by virtue of transmitting the parasite Trypanosoma cruzi. There is no cure for Chagas' disease and therefore controlling R. prolixus is currently the only method of prevention. Understanding the physiology of the disease vector is an important step in developing control measures. Crustacean cardioactive peptide (CCAP is an important neuropeptide in insects because it has multiple physiological roles such as controlling heart rate and modulating ecdysis behaviour. In this study, we have cloned the cDNA sequence of the CCAP receptor (RhoprCCAPR from 5(th instar R. prolixus and found it to be a G-protein coupled receptor (GPCR. The spatial expression pattern in 5(th instars reveals that the RhoprCCAPR transcript levels are high in the central nervous system, hindgut and female reproductive systems, and lower in the salivary glands, male reproductive tissues and a pool of tissues including the dorsal vessel, trachea, and fat body. Interestingly, the RhoprCCAPR expression is increased prior to ecdysis and decreased post-ecdysis. A functional receptor expression assay confirms that the RhoprCCAPR is activated by CCAP (EC50 = 12 nM but not by adipokinetic hormone, corazonin or an extended FMRFamide. The involvement of CCAP in controlling heartbeat frequency was studied in vivo and in vitro by utilizing RNA interference. In vivo, the basal heartbeat frequency is decreased by 31% in bugs treated with dsCCAPR. Knocking down the receptor in dsCCAPR-treated bugs also resulted in loss of function of applied CCAP in vitro. This is the first report of a GPCR knock-down in R. prolixus and the first report showing that a reduction in CCAPR transcript levels leads to a reduction in cardiac output in any insect.

  17. An Insight into the Transcriptome of the Digestive Tract of the Bloodsucking Bug, Rhodnius prolixus

    Science.gov (United States)

    Ribeiro, José M. C.; Genta, Fernando A.; Sorgine, Marcos H. F.; Logullo, Raquel; Mesquita, Rafael D.; Paiva-Silva, Gabriela O.; Majerowicz, David; Medeiros, Marcelo; Koerich, Leonardo; Terra, Walter R.; Ferreira, Clélia; Pimentel, André C.; Bisch, Paulo M.; Leite, Daniel C.; Diniz, Michelle M. P.; Junior, João Lídio da S. G. V.; Da Silva, Manuela L.; Araujo, Ricardo N.; Gandara, Ana Caroline P.; Brosson, Sébastien; Salmon, Didier; Bousbata, Sabrina; González-Caballero, Natalia; Silber, Ariel Mariano; Alves-Bezerra, Michele; Gondim, Katia C.; Silva-Neto, Mário Alberto C.; Atella, Georgia C.; Araujo, Helena; Dias, Felipe A.; Polycarpo, Carla; Vionette-Amaral, Raquel J.; Fampa, Patrícia; Melo, Ana Claudia A.; Tanaka, Aparecida S.; Balczun, Carsten; Oliveira, José Henrique M.; Gonçalves, Renata L. S.; Lazoski, Cristiano; Rivera-Pomar, Rolando; Diambra, Luis; Schaub, Günter A.; Garcia, Elói S.; Azambuja, Patrícia; Braz, Glória R. C.; Oliveira, Pedro L.

    2014-01-01

    The bloodsucking hemipteran Rhodnius prolixus is a vector of Chagas' disease, which affects 7–8 million people today in Latin America. In contrast to other hematophagous insects, the triatomine gut is compartmentalized into three segments that perform different functions during blood digestion. Here we report analysis of transcriptomes for each of the segments using pyrosequencing technology. Comparison of transcript frequency in digestive libraries with a whole-body library was used to evaluate expression levels. All classes of digestive enzymes were highly expressed, with a predominance of cysteine and aspartic proteinases, the latter showing a significant expansion through gene duplication. Although no protein digestion is known to occur in the anterior midgut (AM), protease transcripts were found, suggesting secretion as pro-enzymes, being possibly activated in the posterior midgut (PM). As expected, genes related to cytoskeleton, protein synthesis apparatus, protein traffic, and secretion were abundantly transcribed. Despite the absence of a chitinous peritrophic membrane in hemipterans - which have instead a lipidic perimicrovillar membrane lining over midgut epithelia - several gut-specific peritrophin transcripts were found, suggesting that these proteins perform functions other than being a structural component of the peritrophic membrane. Among immunity-related transcripts, while lysozymes and lectins were the most highly expressed, several genes belonging to the Toll pathway - found at low levels in the gut of most insects - were identified, contrasting with a low abundance of transcripts from IMD and STAT pathways. Analysis of transcripts related to lipid metabolism indicates that lipids play multiple roles, being a major energy source, a substrate for perimicrovillar membrane formation, and a source for hydrocarbons possibly to produce the wax layer of the hindgut. Transcripts related to amino acid metabolism showed an unanticipated priority for

  18. An insight into the transcriptome of the digestive tract of the bloodsucking bug, Rhodnius prolixus.

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    José M C Ribeiro

    Full Text Available The bloodsucking hemipteran Rhodnius prolixus is a vector of Chagas' disease, which affects 7-8 million people today in Latin America. In contrast to other hematophagous insects, the triatomine gut is compartmentalized into three segments that perform different functions during blood digestion. Here we report analysis of transcriptomes for each of the segments using pyrosequencing technology. Comparison of transcript frequency in digestive libraries with a whole-body library was used to evaluate expression levels. All classes of digestive enzymes were highly expressed, with a predominance of cysteine and aspartic proteinases, the latter showing a significant expansion through gene duplication. Although no protein digestion is known to occur in the anterior midgut (AM, protease transcripts were found, suggesting secretion as pro-enzymes, being possibly activated in the posterior midgut (PM. As expected, genes related to cytoskeleton, protein synthesis apparatus, protein traffic, and secretion were abundantly transcribed. Despite the absence of a chitinous peritrophic membrane in hemipterans - which have instead a lipidic perimicrovillar membrane lining over midgut epithelia - several gut-specific peritrophin transcripts were found, suggesting that these proteins perform functions other than being a structural component of the peritrophic membrane. Among immunity-related transcripts, while lysozymes and lectins were the most highly expressed, several genes belonging to the Toll pathway - found at low levels in the gut of most insects - were identified, contrasting with a low abundance of transcripts from IMD and STAT pathways. Analysis of transcripts related to lipid metabolism indicates that lipids play multiple roles, being a major energy source, a substrate for perimicrovillar membrane formation, and a source for hydrocarbons possibly to produce the wax layer of the hindgut. Transcripts related to amino acid metabolism showed an unanticipated

  19. Impact of residual spraying on Rhodnius prolixus and Triatoma dimidiata in the department of Zacapa in Guatemala

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    J Nakagawa

    2003-03-01

    Full Text Available As a vector control program to control Chagas disease in Guatemala, residual spraying of Rhodnius prolixus and Triatoma dimidiata was performed, and its impact was measured in the department of Zacapa. In order to identify infested villages and determine the degree of infestation, a baseline entomological survey to identify municipalities infested with vectors followed by an additional vector survey in areas known to be infested was conducted. Residual spraying using pyrethroid insecticides was performed at all the villages identified as being infested with the vectors. The residual spraying was shown to be highly effective against both vectors by the decrease in infestation indices after spraying. Analysis of the cost-effectiveness of the spraying showed that the average cost of insecticides per house is high when compared with that in Southern Cone countries.

  20. Short and long-term effects of azadirachtin A on development and egg production of Rhodnius prolixus

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    Eloi S. Garcia

    1990-03-01

    Full Text Available Azadirachtin A was given through a blood meal to 4th-instar larvae and to adult females of Rhodnius prolixus. Development (ecdysis and egg production were inhibited in a dose-dependent manner. Long-term experiments with subsequent four feedings on azadirachtin-free blood were performed with 4th-instar larvae and with adult females. Only in the low-dose azadirachtin larval groups (0.01 and 0.1 microng/ml of blood, development was partially restored; after a single 1.0 microng/ml treatment about 50% of the treated larvae were still alive 120 days later without any adult emergence. Similarly fed females had a dose-dependent lower survival and egg deposition rate. The results are discussed in relation to the mode of azadirachtin A action.

  1. Elemental content changes in hemolymph of Rhodnius prolixus due to mercury contamination: a study using SR-TXRF

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    Mantuano, A.; Oliveira, A.P.; Barroso, R.C. [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil); Almeida, A.P.; Braz, D.; Cardoso, S.C. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Figueiredo, M.B.; Azambuja, P. [Fundacao Instituto Osvaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil); Gonzalez, M.S. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2012-07-01

    Full text: In recent years, the effects of pollution on the health of humans and other vertebrates have been extensively studied. However, the effects on some invertebrates are comparatively unknown. Research has demonstrated that toxic metals interfere with the reproduction, development and immune defenses of some terrestrial and marine invertebrates. Depending on environmental conditions, pollution produces chronic and acute effects on different systems and organs of animals. In general, some more toxic elements like arsenic, cadmium, lead, mercury and nickel in contact with organisms change cellular structures, enzyme activities, and in some cases destroy the physiological integrities of the tissues. In insects, the effects of pollutants depend upon the species studied. In this work, we investigated the changes in elemental contents in the hemolymph of Rhodnius prolixus on 2 and 5 days after feeding on blood containing mercury chloride. R. Prolixus is an obligated hematophagous Hemiptera and one of the most important insect vectors of trypanosoma cruzi, the causative agent of Chagas disease. The SR-TXRF measurements were performed at the X-ray fluorescence (XRF) beamline facility in Brazilian Synchrotron Light Laboratory LNLS/Brazil. The major elements Cl, K, Ca, Mn, Fe, Cu, Zn, Se, Br, Rb, K were found in all hemolymph samples analysed. Insects treated with HgCl2 had reduced Cl and Ca levels, whereas the same treatment had enhanced Br levels in comparison with non- treated control insects. (author)

  2. Fungal flora of the digestive tract of Rhodnius prolixus, Rhodnius neglectus, Diptelanogaster maximus and Panstrongylus megistus, vectors of Trypanosoma cruzi, Chagas, 1909 Flora fúngica do trato digestivo de Rhodnius prolixus, Rhodnius neglectus, Diptelanogaster maximus e Panstrongylus megistus vetores de Trypanosoma cruzi, Chagas 1909

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    Aurea Maria Lage de Moraes

    2004-12-01

    Full Text Available This paper reports a study on the mycobiota in the digestive tract of four important species of triatomines: Rhodnius prolixus, R. neglectus, Diptelanogaster maximus and Panstrongylus megistus. The digestive tracts of 90 adults and 425 nymphs of these four triatomine species were studied and 365 fungal strains were isolated. The genera with the greatest number of species were Aspergillus, Penicillium (14 species in each genus, Acremonium and Cladosporium (three species in each genus, and the most frequent species, in decreasing order, were Aspergillus awamori, Penicillium corylophilum, Cladosporium herbarum and Aspergillus niger. It was concluded that, among the isolated fungi, Aspergillus niger and Penicillium corylophilum might be part of the natural flora of the digestive tract of triatomines.Um estudo da micobiota do trato digestivo de quatro importantes espécies de triatomíneos, Rhodnius prolixus, R. neglectus, Diptelanogaster maximus e Panstrongylus megistus, foi realizado. Foram examinados os tratos digestivos de 90 adultos e 425 ninfas destas espécies de triatomíneos e 365 cepas fúngicas foram isoladas. Os gêneros com o maior número de espécies encontradas foram Aspergillus, Penicillium (14 espécies cada, Acremonium e Cladosporium (3 espécies cada e as espécies mais freqüentes, em ordem decrescente, foram Aspergillus awamori, Penicillium corylophilum, Cladosporium herbarum e Aspergillus niger. Dentre os fungos isolados, concluímos que Aspergillus niger e Penicillium corylophilum possam fazer parte da flora natural do trato digestivo destes triatomíneos.

  3. Differential effects of ambient temperature on warm cell responses to infrared radiation in the bloodsucking bug Rhodnius prolixus.

    Science.gov (United States)

    Zopf, Lydia M; Lazzari, Claudio R; Tichy, Harald

    2014-03-01

    Thermoreceptors provide animals with background information about the thermal environment, which is at least indirectly a prerequisite for thermoregulation and assists bloodsucking insects in the search for their host. Recordings from peg-in-pit sensilla and tapered hairs on the antennae of the bug Rhodnius prolixus revealed two physiologically different types of warm cells. Both types responded more strongly to temperature pulses produced by switching between two air streams at different constant temperatures than to infrared radiation pulses employed in still air. In addition, both warm cells were better able to discriminate small changes in air temperature than in infrared radiation. As convective and radiant heat determines the discharge, it is impossible for a single warm cell to signal the nature of the stimulus unequivocally. Individual responses are ambiguous, not with regard to temperature change, but with regard to its source. We argue that the bugs use mechanical flow information to differentiate between pulses of convective and radiant heat. However, if pulses of radiant heat occur together with a constant temperature air stream, the mechanical cues would not allow avoiding ambiguity that convective heat introduces into radiant heat stimulation. In this situation, the warm cell in the tapered hairs produced stronger responses than those in the peg-in-pit sensilla. The reversal in the excitability of the two types of warm cells provides a criterion by which to distinguish the combination of convective and radiant heat from the stimuli presented alone.

  4. The distribution and function of serotonin in the large milkweed bug, Oncopeltus fasciatus. a comparative study with the blood-feeding bug, Rhodnius prolixus.

    Science.gov (United States)

    Miggiani, L; Orchard, I; TeBrugge, V

    1999-11-01

    The blood-feeding hemipteran, Rhodnius prolixus, ingests a large blood meal at the end of each larval stage. To accommodate and process this meal, its cuticle undergoes plasticisation, and its gut and Malpighian tubules respectively absorb and secrete a large volume of water and salts for rapid diuresis. Serotonin has been found to be integral to the feeding process in this animal, along with a diuretic peptide(s). The large milkweed bug, Oncopeltus fasciatus, tends to feed in a more continuous and abstemious manner, and therefore may have different physiological requirements than the blood feeder. Unlike R. prolixus, O. fasciatus is lacking serotonin-like immunoreactive dorsal unpaired median neurons in the mesothoracic ganglionic mass, and lacks serotonin-like immunoreactive neurohaemal areas and processes on the abdominal nerves, integument, salivary glands, and anterior junction of the foregut and crop. The salivary glands and crop do, however, respond to serotonin with increased levels of cAMP, while the integument and Malpighian tubules do not. In addition, O. fasciatus Malpighian tubules respond to both O. fasciatus and R. prolixus partially purified CNS extracts, which are likely to contain any native diuretic peptides. Thus, while serotonin and diuretic peptides may be involved in tubule control in R. prolixus, the latter may be of greater importance in O. fasciatus.

  5. Efecto teratogénico y toxico de ácidos grasos de cadena corta insaturados, en Rhodnius prolixus Teratogenic and toxic effect of unsaturated fatty acids of short chain, in Rhodnius prolixus

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    Ivonne Gomez

    1985-12-01

    Full Text Available Se estudia el papel teratogénico de dos ácidos grasos insaturados de cadena corta, ácido octinoico y ácido undecilénico, sobre insectos de metamorfosis hemimetábola, Rhodnius prolixus (Hemiptera. La penetración de los ácidos, se realiza a través de la cutícula del abdomen y de los tarsos, se presenta como una acción independiente del grado de distensión de la misma, ya que sus efectos se registran tanto en los insectos repletos, como en los hambrientos; tanto en los tratados tópicamente como en aquellos donde la droga se aplicó al papel de soporte. Los ácidos estudiados aparentemente no afectan la formación de la cutícula, ni la melanización, como tampoco afecta el proceso de la muda. Los daños inducidos por estos ácidos se presentam al azar tanto en los apéndices locomotores como en los cefálicos, observándose un desplazamiento a la proboscide a medida que se incrementa la dosis. De las malformaciones en la proboscide, es el labio el mas dramáticamente dañado, aunque también se presentan daños en los otros apéndices bucales, aisladamente o junto con el daño del labio. El daño en los apéndices locomotores está frecuentemente desplazado al segundo y tercer par de patas, mientras que el par, fue el menos afectado. El ácido octinoico se comportó como teratogénico en las dosis que fueron letales para el insecto con el ácido undecilénico.The teratogenic role of two short-chain unsaturated fatty acids, octinoic acid and undecylenic acid on the hemimetabolic metamorphosis of the insect Rhodnius prolixus (Hemipter is studied. The acids penetrate through the cuticle of the abdomen and tarsi, independently of the amount of distention. The effects are registered equally in satiated or hungry insects, in those treated topically or in those where the treatment was applied to the support paper. The acids apparently do not affect the formation of the cuticle, melanization, nor the metamorphic process. The damage induced by

  6. Allosteric regulation of 6-phosphofructo-1-kinase activity of fat body and flight muscle from the bloodsucking bug Rhodnius prolixus

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    Gutemberg G. Alves

    2007-03-01

    Full Text Available 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. Muscle extracts are more responsible than fat body to ATP and fructose 6-phosphate, both substrates of PFK. Allosteric regulation exerted by different effectors such as ADP, AMP and fructose 2,6-phosphate presented a singular pattern for each tissue. Optimal pH (8.0-8.5 and sensitivity to pH variation was very similar, and citrate was unable to inhibit PFK activity in both extracts. Our results suggest the existence of a particular PFK activity for each tissue, with regulatory patterns that are consistent with their physiological roles.A atividade da fosfofrutocinase (PFK de Rodnius prolixus, um inseto hematófago, o qual vôa somente pequenas distâncias, foi medida e comparada em dois tecidos metabolicamente ativos - músculo de asa e corpo gorduroso. A atividade desta importante enzima glicolítica regulatória foi muito mais pronunciada em músculo de asa (15,1 ±1,4 U/mg do que em extrato de corpo gorduroso (3,6 ±0,4 U/mg embora este último tenha apresentado níveis mais altos da enzima por quantidade de proteína, como medido por western-blotting. Extratos de músculo foram mais responsivos do que corpo gorduroso para ATP e frutose-6-fosfato, ambos substratos da PFK. A regulação alostérica exercida por diferentes efetores tais como ADP, AMP, frutose-2,6-bisfosfato apresentou um padrão singular para cada tecido. O pH ótimo (8,0-8,5 e a sensibilidade a variações de pH, foram muito similares e o citrato foi incapaz de inibir a atividade da PFK em

  7. Técnica para extraer cantidad apreciable de hemolinfa y sacar fácilmente glándulas salivales en ninfas de quinto estadio y adultos de Rhodnius Prolixus

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    Ernesto Osorno Mesa

    1965-07-01

    Full Text Available Se describen minuciosamente los diferentes pasos para extracción de hemolinfa con micropipetas, en ninfas de 5º estadio y adultos de Rhodnius prolixus, lo mismo que para el aislamiento de las glándulas salivales. Se anotan las ventajas y aplicaciones de estas técnicas, en investigaciones parasitológicas, especialmente sobre Trypanosomiasis.

  8. Cloning and Functional Characterization of Octβ2-Receptor and Tyr1-Receptor in the Chagas Disease Vector, Rhodnius prolixus

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    Sam Hana

    2017-09-01

    Full Text Available Octopamine and tyramine, both biogenic amines, are bioactive chemicals important in diverse physiological processes in invertebrates. In insects, octopamine and tyramine operate analogously to epinephrine and norepinephrine in the vertebrates. Octopamine and tyramine bind to G-protein coupled receptors (GPCRs leading to changes in second messenger levels and thereby modifying the function in target tissues and insect behavior. In this paper, we report the cDNA sequences of two GPCRs, RhoprOctβ2-R, and RhoprTyr1-R, have been cloned and functionally characterized from Rhodnius prolixus. Octopamine and tyramine each activate RhoprOctβ2-R and RhoprTyr1-R in a dose-dependent manner. Octopamine is one order of magnitude more potent than tyramine in activating RhoprOctβ2-R. Tyramine is two orders of magnitude more potent than octopamine in activating RhoprTyr1-R. Phentolamine and gramine significantly antagonize RhoprOctβ2-R, whereas yohimbine and phenoxybenzamine are effective blockers of RhoprTyr1-R. The transcripts of both receptors are enriched in the central nervous system (CNS and are expressed throughout the adult female reproductive system. It has been shown in other insects that Octβ2-R is essential for processes such as ovulation and fertilization. We previously reported that octopamine and tyramine modulate oviducts and bursa contractions in R. prolixus. Our data confirm the importance of octopamine and tyramine signaling in the reproductive system of R. prolixus.

  9. Alimentación y defecación en triatominos del género Rhodnius (Hemiptera: Reduviidae alimentados con sangre humana

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    E. Aldana

    2001-06-01

    Full Text Available Se estudió el comportamiento alimenticio y de defecación de Rhodnius prolixus Stal, 1859, R. robustus Larrousse, 1927, R. neivai Lent, 1953 y R. pictipes Stal, 1872 alimentados artificialmente con sangre humana en condiciones de laboratorio. La ninfa I de todas las especies no defecaron en la primera media hora después de haber iniciado la ingesta. R. pictipes no se acercó a picar en el alimentador artificial aunque si lo hizo cuando el alimento se ofreció directamente sobre el cuerpo humano. Las ninfas y adultos de R. prolixus mostraron índices de defecación (ID superiores a los correspondientes de las otras especies, y la ninfa III presentó el mayor ID=1.62. La mayoría de individuos de todos los estadíos de desarrollo aceptaron el alimento en un tiempo entre 0 y 3 min y se alimentaron en menos de 15 minutos.Feeding and defecaction behavior of Rhodnius prolixus Stal, 1859, R. robustus Larrousse, 1927, R. neivai Lent, 1953 and R. pictipes Stal, 1872, artificially fed on human blood, were studied under laboratory conditions. In all species, first instar nymphs did not defecate in the first 30 minutes after feeding. R. pictipes did not accept artificial feeding but fed directly on humans. Nymph and adult R. prolixus had a higher defecation index (DI than other species; third instar nymphs had the highest DI=1.62. In all instars, most individuals accepted the food in £ 3 minutes and finished feeding in less than 15 minutes.

  10. Silencing of Iron and Heme-Related Genes Revealed a Paramount Role of Iron in the Physiology of the Hematophagous Vector Rhodnius prolixus

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    Ana B. Walter-Nuno

    2018-02-01

    Full Text Available Iron is an essential element for most organisms However, free iron and heme, its complex with protoporphyrin IX, can be extremely cytotoxic, due to the production of reactive oxygen species, eventually leading to oxidative stress. Thus, eukaryotic cells control iron availability by regulating its transport, storage and excretion as well as the biosynthesis and degradation of heme. In the genome of Rhodnius prolixus, the vector of Chagas disease, we identified 36 genes related to iron and heme metabolism We performed a comprehensive analysis of these genes, including identification of homologous genes described in other insect genomes. We observed that blood-meal modulates the expression of ferritin, Iron Responsive protein (IRP, Heme Oxygenase (HO and the heme exporter Feline Leukemia Virus C Receptor (FLVCR, components of major pathways involved in the regulation of iron and heme metabolism, particularly in the posterior midgut (PM, where an intense release of free heme occurs during the course of digestion. Knockdown of these genes impacted the survival of nymphs and adults, as well as molting, oogenesis and embryogenesis at different rates and time-courses. The silencing of FLVCR caused the highest levels of mortality in nymphs and adults and reduced nymph molting. The oogenesis was mildly affected by the diminished expression of all of the genes whereas embryogenesis was dramatically impaired by the knockdown of ferritin expression. Furthermore, an intense production of ROS in the midgut of blood-fed insects occurs when the expression of ferritin, but not HO, was inhibited. In this manner, the degradation of dietary heme inside the enterocytes may represent an oxidative challenge that is counteracted by ferritins, conferring to this protein a major antioxidant role. Taken together these results demonstrate that the regulation of iron and heme metabolism is of paramount importance for R. prolixus physiology and imbalances in the levels of

  11. Elemental changes in hemolymph and urine of Rhodnius prolixus induced by in-vitro exposure to mercury: A study using SR-TXRF

    Energy Technology Data Exchange (ETDEWEB)

    Mantuano, Andrea; Barroso, Regina C. [Physics Institute/State University of Rio de Janeiro (UERJ), RJ (Brazil); Almeida, Andre P. de; Braz, Delson [Nuclear Engineering Program/COPPE/Federal University of Rio de Janeiro, RJ (Brazil); Cardoso, Simone C. [Physics Institute/Federal University of Rio de Janeiro, RJ (Brazil); Penna, Patricia A.; Gonzalez, Marcelo S. [Laboratory of Biochemistry and Physiology of Insects/Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, RJ (Brazil)

    2011-07-01

    Full text: In the last years have been studied the effects of the pollution of humans and others vertebrates, however, the effects on invertebrates are poorly knows. Some pollutants introduced in aquatic and terrestrial ecosystems are potentially toxic to living organisms. Almost the environmental pollutants, the heavy metals are not degradable and can persist during long time of many ecosystems causing ecologic changes often disastrous to species that habit there. Actually some works has shown that the heavy metals beyond be toxic and interfere on development and reproduction of some species of terrestrial and marine invertebrates. When are present in cells, the chemical form and connection type of metals are critical factors that determinate the toxicity. So, the ambient pollution has chronic effects and acute of animals health and can affect any systems and organs. The intoxications that current often are caused by aluminum, arsenic, barium, beryllium, cadmium, lead, mercury and nickel. Know that these elements can change cellular structures, enzymes and replace metal cofactors in enzyme activities. In insects, the effects of pollution change according to specie studied. The pollution can act on the weight reduction and increasing the relative growth rate. In this work, we investigated the effect of mercury exposure on the elemental content in hemolymph and urine of Rhodnius prolixus the insect vector of Chagas' disease, which is one of the most important vectors in Latin American and also, the most well-know studied insect in terms of both physiology and vector-parasite interactions. Five-stage nymphs of Rhodnius prolixus were collected from colony of a Laboratory Physiology and Biochemistry of Insects, Institute Oswaldo Cruz RJ. For treatment of insects, mercury chloride has been added to rabbit blood. After feeding the nymphs were separated and packed for two days for collection of hemolymph and urine. The SR-TXRF measurements were performed at the X

  12. Elemental changes in hemolymph and urine of Rhodnius prolixus induced by in-vitro exposure to mercury: A study using SR-TXRF

    International Nuclear Information System (INIS)

    Mantuano, Andrea; Barroso, Regina C.; Almeida, Andre P. de; Braz, Delson; Cardoso, Simone C.; Penna, Patricia A.; Gonzalez, Marcelo S.

    2011-01-01

    Full text: In the last years have been studied the effects of the pollution of humans and others vertebrates, however, the effects on invertebrates are poorly knows. Some pollutants introduced in aquatic and terrestrial ecosystems are potentially toxic to living organisms. Almost the environmental pollutants, the heavy metals are not degradable and can persist during long time of many ecosystems causing ecologic changes often disastrous to species that habit there. Actually some works has shown that the heavy metals beyond be toxic and interfere on development and reproduction of some species of terrestrial and marine invertebrates. When are present in cells, the chemical form and connection type of metals are critical factors that determinate the toxicity. So, the ambient pollution has chronic effects and acute of animals health and can affect any systems and organs. The intoxications that current often are caused by aluminum, arsenic, barium, beryllium, cadmium, lead, mercury and nickel. Know that these elements can change cellular structures, enzymes and replace metal cofactors in enzyme activities. In insects, the effects of pollution change according to specie studied. The pollution can act on the weight reduction and increasing the relative growth rate. In this work, we investigated the effect of mercury exposure on the elemental content in hemolymph and urine of Rhodnius prolixus the insect vector of Chagas' disease, which is one of the most important vectors in Latin American and also, the most well-know studied insect in terms of both physiology and vector-parasite interactions. Five-stage nymphs of Rhodnius prolixus were collected from colony of a Laboratory Physiology and Biochemistry of Insects, Institute Oswaldo Cruz RJ. For treatment of insects, mercury chloride has been added to rabbit blood. After feeding the nymphs were separated and packed for two days for collection of hemolymph and urine. The SR-TXRF measurements were performed at the X

  13. X-ray cone beam microtomography for quantitative assessment of tracheal and pharyngeal volumes of Rhodnius prolixus

    International Nuclear Information System (INIS)

    Souza, Izabella Soares de

    2017-01-01

    In the past decade microcomputerized tomography imaging using synchrotron radiation has become a powerful technique to generate high resolution images of Rhodinus prolixus. Images of soft tissues (protocerebrum and muscles) and dense structures (pharynx, trachea and esophagus) of R. prolixus head have been obtained using synchrotron radiation microtomography in mono and polychromatic configuration, respectively. Advancements in conventional microtomography have increased the achievable resolution and contrast, making this relatively inexpensive and widely available technology potentially useful for studies of insect internal morphology. The main goal of this work was to provide a new set of high quality microtomographic images of R. prolixus achieved by means of a desktop X-ray microtomograph. It allows the three-dimensional visualization of important chitinized structures: pharynx and tracheae. Pharyngeal and tracheal volumes were quantitatively evaluated at different days (1, 4, 10, 15 and 20) after feeding. The results suggest that variation of average volumes could be attributed to insect hormone 20-hydroxy-ecdysone (20-OH-Ec) pulse at 11 days after feeding. Pharyngeal volumes decrease 3.80 times. On the other hand, tracheal volumes increase 1.78 times. Head total volume showed similar trends than trachea. (author)

  14. Application of synchrotron radiation phase-contrast microtomography with iodine staining to Rhodnius prolixus head during ecdysis period

    Science.gov (United States)

    Sena, G.; Nogueira, L. P.; Braz, D.; Colaço, M. V.; Azambuja, P.; Gonzalez, M. S.; Tromba, G.; Mantuano, A.; Costa, F. N.; Barroso, R. C.

    2018-05-01

    Synchrotron radiation phase-contrast microtomography (SR-PHC-CT) has become an important tool in studies of insects, mainly Rhodinius prolixus, the insect vector of Chagas disease. A previous work has shown that SR-PHC-CT is an excellent technique in studies about the ecdysis process of R.prolixus head. The term ecdysis refers to the set of behaviors by which an insect extracts itself from an old exoskeleton. The exoskeleton formation is indispensable for the evolutionary success of insect species, so failure to complete ecdysis will, in most cases result in death, making this process an excellent target in the search for new insect pest management strategies. Understanding the behavior of the ecdysis process is fundamental for the non-proliferation of Chagas disease. Despite it has been possible to identify the moulting process in the first work, main structures of the R.prolixus head could not be identified. In this work, it was developed a staining protocol which enabled the identification of these important structures using Iodine at SYRMEP beamline of ELETTRA. In the 3D images, it was possible to segment essential structures in the process of ecdysis. These structures have never been presented previously in the moulting period with SR-PHC-CT.

  15. [Development of Rhodnius pictipes Stal, 1872 fed on mice and through a silicone membrane (Hemiptera, Reduviidae, Triatominae)].

    Science.gov (United States)

    Rocha, D da S; da Fonseca, A H; Costa, F A; Jurberg, J; Galvão, C

    1997-01-01

    Rhodnius pictipes (Hemiptera, Reduviidae) from Serra Norte, State of Pará, Brazil, acclimatized in an insectary at the Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Departamento de Entomologia, Instituto Oswaldo Cruz, were fed through a silicone membrane. In order to know the viability and the efficiency of this membrane compared with insects fed on mice, the number of bloodmeals taken, period of development of the five nymphal instars, longevity of adults, average amount of blood intake in each meal and percent of mortality were observed. A total of 310 insects, were used, comprising 50 nymphs of each instar, as well as 30 male and 30 female adults. Insects fed artificially had reduced minimal and maximal periods of development than the group fed on mice. The largest relative increase of body weight was observed in the 2nd instar followed by the 1st, and the amount of blood ingested increased during the development, to the 5th instar for both groups. There were no significant differences between the groups fed artificially and in vivo according to Tukey's test for p > 0.05. The percent of mortality in the 1st instar was 18% for artificially fed and 16% for the group fed on mice; these percentages decreased as insects developed until the 4th instar, without mortality, returning to increase in the 5th instar. R. pictipes was shown to be easily adaptable to artificial feeding, and could be considered as an important and viable experimental model.

  16. Psammolestes arthuri NATURALMENTE INFECTADO CON Trypanosoma cruzi ENCONTRADO EN SIMPATRÍA CON Rhodnius prolixus Y Triatoma maculata EN NIDOS DE AVES EN EL ESTADO ANZOÁTEGUI, VENEZUELA I Psammolestes arthuri NATURALLY INFECTED WITH Trypanosoma cruzi FOUND IN SYMPATRY WITH Rhodnius prolixus AND Triatoma maculata ON BIRD NESTS IN ANZOÁTEGUI STATE, VENEZUELA

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    Pedro José Cruz-Guzmán

    2018-04-01

    Full Text Available In Venezuela, Chagas' disease is a public health problem with around 2 million people infected and more than 6 million under risk of infection. In this study the presence of the triatomid Psammolestes arthuri is reported in nests of different species of birds from rural communities of Anzoátegui State, some of them found naturally infected with Trypanosoma cruzi , in sympatry with other species of triatomines ( Rhodnius prolixus y Triatoma maculata . A total of 3,277 triatomine specimens were collected in 478 nests from 6 species of birds ( Phacellodomus rufifrons , Troglodytes aedon , Icterus icterus , I. nigrogularis , Cacicus cela y Psarocolius decumanus . It was found that 99.05% (3246/3277 of specimens were P. arthuri and 0.95% (31/3277 other triatomine species, from which 0.57% (19/3277 were R. prolixus and 0.37% (12/3277 T. mac ulata . Only 0.12% (4/3246 of P. arthuri were infected with T. cr u z i . The parasitological characterization of one T. cr u z i isolate in white male NMRI mice showed high affinity for cardiac, skeletal and smooth muscle cells, with a peak parasitemia of 2.4 x 10 4 parasites/ mL blood stream forms of T. cr u z i and 100% mortality of inoculated mice. This isolate was molecularly typed as belonging to TcIII genotype. The results show that in Anzoátegui State, P. arthuri predominantly feed on blood of birds, representing a low risk for vector transmission of Chagas' disease to humans

  17. Exploring the Role of Rhodtestolin, A Cardio-Inhibitor from the Testes of Rhodnius prolixus, in Relation to the Structure and Function of Reproductive Organs in Insect Vectors of Chagas Disease

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    Marli Maria Lima

    2013-10-01

    Full Text Available Rhodtestolin is a cardio-inhibitor that was first discovered in testes extracts of the blood-feeding insect, Rhodnius prolixus. Its role in reproduction remains unconfirmed, but if delivered to the female during spermatophore formation, it may serve to calm the female and/or relax the vaginal muscles to facilitate delivery and storage of the spermatophore. We describe here the anatomy of reproductive organs in R. prolixus and show that rhodtestolin is present in a low-molecular weight fraction of testes extracts separated by gel filtration, as well as in spermatophores delivered to the female during spermatophore formation. We also report that a rhodtestolin-like factor is present in the testes of R. brethesi, Triatoma dimidiata, T. klugi and Nesotriatoma bruneri, other Reduviidae, which are vectors of Chagas disease. Male secretions in insects are known to modify female behavior after copulation, and the presence of rhodtestolin in several genera of Reduviidae suggests that it plays an important role in reproductive success. Determining this role could lead to developing additional population control strategies for these bugs.

  18. Estructura poblacional y variabilidad genética de Rhodnius prolixus (Hemiptera: Reduviidae procedente de diferentes áreas geográficas de Colombia

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    Diana Carolina López

    2007-01-01

    Resultados. R. prolixus presenta variabilidad genética moderada (Fst 0,057-0,15, entre las poblaciones domiciliadas se encontraron tasas de migración (Nm>1 que revelan flujo genético. Se encontró diferenciación genética de moderada-alta entre la población silvestre de Casanare y las poblaciones domésticas del centro del país (Tolima y Cundinamarca. Conclusión. Las poblaciones domiciliadas de R. prolixus son homogéneas debido a que existe flujo genético entre éstas; lo cual es favorable para el control químico, mientras que la población silvestre agrupa aparte de las domiciliadas. Se evidencia la necesidad de estudiar la estructura genética de los focos silvestres, sus posibles rutas de dispersión y el riesgo epidemiológico que representan.

  19. Monitoring of the Parasite Load in the Digestive Tract of Rhodnius prolixus by Combined qPCR Analysis and Imaging Techniques Provides New Insights into the Trypanosome Life Cycle.

    Directory of Open Access Journals (Sweden)

    Felipe de Almeida Dias

    Full Text Available Here we report the monitoring of the digestive tract colonization of Rhodnius prolixus by Trypanosoma cruzi using an accurate determination of the parasite load by qPCR coupled with fluorescence and bioluminescence imaging (BLI. These complementary methods revealed critical steps necessary for the parasite population to colonize the insect gut and establish vector infection.qPCR analysis of the parasite load in the insect gut showed several limitations due mainly to the presence of digestive-derived products that are thought to degrade DNA and inhibit further the PCR reaction. We developed a real-time PCR strategy targeting the T. cruzi repetitive satellite DNA sequence using as internal standard for normalization, an exogenous heterologous DNA spiked into insect samples extract, to precisely quantify the parasite load in each segment of the insect gut (anterior midgut, AM, posterior midgut, PM, and hindgut, H. Using combined fluorescence microscopy and BLI imaging as well as qPCR analysis, we showed that during their journey through the insect digestive tract, most of the parasites are lysed in the AM during the first 24 hours independently of the gut microbiota. During this short period, live parasites move through the PM to establish the onset of infection. At days 3-4 post-infection (p.i., the parasite population begins to colonize the H to reach a climax at day 7 p.i., which is maintained during the next two weeks. Remarkably, the fluctuation of the parasite number in H remains relatively stable over the two weeks after refeeding, while the populations residing in the AM and PM increases slightly and probably constitutes the reservoirs of dividing epimastigotes.These data show that a tuned dynamic control of the population operates in the insect gut to maintain an equilibrium between non-dividing infective trypomastigote forms and dividing epimastigote forms of the parasite, which is crucial for vector competence.

  20. X-ray cone beam microtomography for quantitative assessment of tracheal and pharyngeal volumes of Rhodnius prolixus; Utilizacao da microtomografia computadorizada com feixe de raios-X conico para a determinacao quantitativa do volume da traqueia e faringe do Rhodnius prolixus

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Izabella Soares de

    2017-07-01

    In the past decade microcomputerized tomography imaging using synchrotron radiation has become a powerful technique to generate high resolution images of Rhodinus prolixus. Images of soft tissues (protocerebrum and muscles) and dense structures (pharynx, trachea and esophagus) of R. prolixus head have been obtained using synchrotron radiation microtomography in mono and polychromatic configuration, respectively. Advancements in conventional microtomography have increased the achievable resolution and contrast, making this relatively inexpensive and widely available technology potentially useful for studies of insect internal morphology. The main goal of this work was to provide a new set of high quality microtomographic images of R. prolixus achieved by means of a desktop X-ray microtomograph. It allows the three-dimensional visualization of important chitinized structures: pharynx and tracheae. Pharyngeal and tracheal volumes were quantitatively evaluated at different days (1, 4, 10, 15 and 20) after feeding. The results suggest that variation of average volumes could be attributed to insect hormone 20-hydroxy-ecdysone (20-OH-Ec) pulse at 11 days after feeding. Pharyngeal volumes decrease 3.80 times. On the other hand, tracheal volumes increase 1.78 times. Head total volume showed similar trends than trachea. (author)

  1. Rhodnius prolixus and Rhodnius robustus–like (Hemiptera ...

    Indian Academy of Sciences (India)

    2013-06-09

    Jun 9, 2013 ... non-directional deviations between the left and the right values of a ... 2011). For example, in Drosophila spp contradictory results have been .... of a lower selection pressure on individuals with reduced flying activity in ...

  2. Description of Rhodnius marabaensis sp. n. (Hemiptera, Reduviidae, Triatominae) from Pará State, Brazil

    Science.gov (United States)

    Souza, Eder dos Santos; Von Atzingen, Noé Carlos Barbosa; Furtado, Maria Betânia; de Oliveira, Jader; Nascimento, Juliana Damieli; Vendrami, Daniel Pagotto; Gardim, Sueli; da Rosa, João Aristeu

    2016-01-01

    Abstract Rhodnius marabaensis sp. n. was collected on 12 May 2014 in the Murumurú Environmental Reserve in the city of Marabá, Pará State, Brazil. This study was based on previous consultation of morphological descriptions of 19 Rhodnius species and compared to the identification key for the genus Rhodnius. The examination included specimens from 18 Rhodnius species held in the Brazilian National and International Triatomine Taxonomy Reference Laboratory in the Oswaldo Cruz Institute in Rio de Janeiro, Brazil. The morphological characteristics of the head, thorax, abdomen, genitalia, and eggs have been determined. Rhodnius prolixus and Rhodnius robustus were examined in more detail because the BLAST analysis of a cyt-b sequence shows they are closely related to the new species, which also occurs in the northern region of Brazil. The most notable morphological features that distinguish Rhodnius marabaensis sp. n. are the keel-shaped apex of the head, the length of the second segment of the antennae, the shapes of the prosternum, mesosternum and metasternum, the set of spots on the abdomen, the male genitalia, the posterior and ventral surfaces of the external female genitalia, and the morphological characteristics of the eggs. Rhodnius jacundaensis Serra, Serra & Von Atzingen (1980) nomen nudum specimens deposited at the Maraba Cultural Center Foundation - MCCF were examined and considered as a synonym of Rhodnius marabaensis sp. n. PMID:27833419

  3. Molecular characterisation of Trypanosoma rangeli strains isolated from Rhodnius ecuadoriensis in Peru, R. colombiensis in Colombia and R. pallescens in Panama, supports a co-evolutionary association between parasites and vectors.

    Science.gov (United States)

    Urrea, D A; Carranza, J C; Cuba, C A Cuba; Gurgel-Gonçalves, R; Guhl, F; Schofield, C J; Triana, O; Vallejo, G A

    2005-03-01

    We present data on the molecular characterisation of strains of Trypanosoma rangeli isolated from naturally infected Rhodnius ecuadoriensis in Peru, from Rhodnius colombiensis, Rhodnius pallescens and Rhodnius prolixus in Colombia, and from Rhodnius pallescens in Panama. Strain characterisation involved a duplex PCR with S35/S36/KP1L primers. Mini-exon gene analysis was also carried out using TrINT-1/TrINT-2 oligonucleotides. kDNA and mini-exon amplification indicated dimorphism within both DNA sequences: (i) KP1, KP2 and KP3 or (ii) KP2 and KP3 products for kDNA, and 380 bp or 340 bp products for the mini-exon. All T. rangeli strains isolated from R. prolixus presented KP1, KP2 and KP3 products with the 340 bp mini-exon product. By contrast, all T. rangeli strains isolated from R. ecuadoriensis, R. pallescens and R. colombiensis, presented profiles with KP2 and KP3 kDNA products and the 380 bp mini-exon product. Combined with other studies, these results provide evidence of co-evolution of T. rangeli strains associated with different Rhodnius species groups east and west of the Andean mountains.

  4. partial characterisation of a trypanosome-lysing

    African Journals Online (AJOL)

    2003-11-01

    Nov 1, 2003 ... Crithidia or Leishmania parasites. Ibrahim et al.(9) further showed that the haemolymph factor was a lectin. ' andahat the midgut. also contained another lectin with different specificity. In Rhodnius prolixus Stal, the vector for Trypanosoma cruzi Chagas, lectins from the haemolymph and the gut agglutinated ...

  5. Novel adipokinetic hormones in the kissing bugs Rhodnius prolixus, Triatoma infestans, Dipetalogaster maxima and Panstrongylus megistrus

    Czech Academy of Sciences Publication Activity Database

    Marco, H. G.; Šimek, Petr; Clark, K. D.; Gäde, G.

    2013-01-01

    Roč. 41, MAR 10 (2013), s. 21-30 ISSN 0196-9781 R&D Projects: GA MZd(CZ) NT11513 Grant - others:National Research Foundation(ZA) IFR 2008071500048; National Research Foundation(ZA) FA 2007021300002 Institutional support: RVO:60077344 Keywords : insects * kissing bugs * reduviidae Subject RIV: ED - Physiology Impact factor: 2.614, year: 2013 http://www.sciencedirect.com/science/article/pii/S0196978112004433

  6. Application of phase-contrast X-ray microtomography to study the internal structures of Rhodium prolixus

    International Nuclear Information System (INIS)

    Almeida, Andre P. de; Soares, Jose; Barroso, Regina C.; Braz, Delson; Cardoso, Simone C.; Garcia, Eloi S.; Azambuja, Patricia; Gonzalez, Marcelo S.

    2011-01-01

    The PhC-SR-μCT is a nondestructive technique that allows the microanatomical investigations and 3D images reconstructions within a short time. This technique performed in blood sucker, Rhodnius prolixus - one of the most important primary vectors of of Trypanosoma cruzi, ethiologic agent of Chagas' disease in Latin America and also the most well-know studied insect in terms of both physiology and vector-parasite interactions. However, little is known about the development and structure of its internal organs. The aim of this work is to provide a non-invasive option for studying the internal structures of the main vector of Chagas' disease, which should help to answer important questions concerning anatomy, development, structure and plasticity of insect in general. Three-dimensional rendering images can provide a detailed knowledge of the interior of the insect, which is crucial for a better understanding of its function and evolution. (author)

  7. Application of phase-contrast X-ray microtomography to study the internal structures of Rhodium prolixus

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Andre P. de; Soares, Jose; Barroso, Regina C. [State University of Rio de Janeiro (UERJ), RJ (Brazil). Physics Institute; Braz, Delson, E-mail: delson@lin.ufrj.b [Federal University of Rio de Janeiro (COPPE/UFRJ), RJ (Brazil). Nuclear Engineering Program; Cardoso, Simone C., E-mail: simone@if.ufrj.b [Federal University of Rio de Janeiro (IF/UFRJ), RJ (Brazil). Physics Institute; Garcia, Eloi S.; Azambuja, Patricia [Oswaldo Cruz Institute (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Lab. of Biochemistry and Physiology of Insects; Gonzalez, Marcelo S. [Federal University Fluminense (UFF), Niteroi, RJ (Brazil). Dept. of General Biology

    2011-07-01

    The PhC-SR-{mu}CT is a nondestructive technique that allows the microanatomical investigations and 3D images reconstructions within a short time. This technique performed in blood sucker, Rhodnius prolixus - one of the most important primary vectors of of Trypanosoma cruzi, ethiologic agent of Chagas' disease in Latin America and also the most well-know studied insect in terms of both physiology and vector-parasite interactions. However, little is known about the development and structure of its internal organs. The aim of this work is to provide a non-invasive option for studying the internal structures of the main vector of Chagas' disease, which should help to answer important questions concerning anatomy, development, structure and plasticity of insect in general. Three-dimensional rendering images can provide a detailed knowledge of the interior of the insect, which is crucial for a better understanding of its function and evolution. (author)

  8. Billgren versus Edelfelt : The Illustrations for J. L. Runeberg's Fanrik Stals sagner

    NARCIS (Netherlands)

    van der Hoeven, Adriaan

    2008-01-01

    Albert Edelfelt's Illustrations for Runeberg's Fanrik Stals sagner from 1900 are without doubt the best known of all made for this epic narrative. Nevertheless, in 2004, Swedish artist Ernst Billgren took up the challenge of creating a new image of the Tales of Ensign Stal. Edelfelt works in a

  9. Behandeling van lucht uit een traditionele stal voor vleeskuikens met een chemische wasser

    NARCIS (Netherlands)

    Hol, J.M.G.; Wever, A.C.; Groot Koerkamp, P.W.G.

    1999-01-01

    In dit onderzoek werd de reductie van de ammoniakemissie gemeten door toepassing van een chemische wasser. Deze wasser behandelde de lucht die afkomstig was uit een traditionele stal voor vleeskuikens.

  10. Cysteine proteases from bloodfeeding arthropod ectoparasites

    Czech Academy of Sciences Publication Activity Database

    Sojka, Daniel; Francischetti, I.M.B.; Calvo, E.; Kotsyfakis, Michalis

    2011-01-01

    Roč. 712, - (2011), s. 177-191 ISSN 0065-2598 R&D Projects: GA AV ČR IAA600960910; GA AV ČR IAA600960811; GA AV ČR KJB600960911; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : TICK HAEMAPHYSALIS-LONGICORNIS * PROLIXUS STAL HEMIPTERA * YELLOW-FEVER MOSQUITO * BLOOD-MEAL DIGESTION * L-LIKE ENZYME * BOOPHILUS-MICROPLUS * RHODNIUS-PROLIXUS * CATHEPSIN-B * ASPARAGINYL ENDOPEPTIDASES/LEGUMAINS * PROTEOLYTIC ACTIVATION Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.093, year: 2011

  11. Sodium pumps in the Malpighian tubule of Rhodnius sp.

    Directory of Open Access Journals (Sweden)

    CARUSO-NEVES CELSO

    2000-01-01

    Full Text Available Malpighian tubule of Rhodnius sp. express two sodium pumps: the classical ouabain-sensitive (Na+ + K+ATPase and an ouabain-insensitive, furosemide-sensitive Na+-ATPase. In insects, 5-hydroxitryptamine is a diuretic hormone released during meals. It inhibits the (Na+ + K+ATPase and Na+ -ATPase activities indicating that these enzymes are involved in fluid secretion. Furthermore, in Rhodnius neglectus, proximal cells of Malpighian tubule exposed to hyperosmotic medium, regulate their volume through a mechanism called regulatory volume increase. This regulatory response involves inhibition of the (Na+ + K+ATPase activity that could lead to accumulation of active osmotic solute inside the cell, influx of water and return to the normal cell volume. Adenosine, a compound produced in stress conditions, also inhibits the (Na+ + K+ATPase activity. Taken together these data indicate that (Na+ + K+ATPase is a target of the regulatory mechanisms of water and ions transport responsible for homeostasis in Rhodnius sp.

  12. Jak se z úspěchu stal neúspěch

    Czech Academy of Sciences Publication Activity Database

    Řípa, Milan

    -, říjen (2015) Institutional support: RVO:61389021 Keywords : John Cockcroft * ZETA * Peter Thonemann * Harwell Subject RIV: BL - Plasma and Gas Discharge Physics http://www.vedaprozivot.cz/sd/novinky/hlavni-stranka/151007-jak-se-z-uspechu-stal-neuspech.html

  13. Morphology and Histology of the Female Reproductive System of Abedus ovatus Stal (Belostomatidae: Hemiptera: Insecta

    Directory of Open Access Journals (Sweden)

    Lalitha TG

    1997-01-01

    Full Text Available In Abedus ovatus Stal, the female reproductive system consists of a pair of ovaries leading to oviduct and opens out by genital aperture. Each ovary is composed of five telotrophic ovarioles, with four different regions, terminal filament, germarium, vitellarium and pedicel. Germarium and vitellarium are the germ tubes in which the development of oocyte occurs. In the germarium, the differentiation of trophocytes into young oocytes was observed in three zones, ZI, ZII and ZIII. Further development of oocytes in the vitellarium could be divided into seven stages, STI STVII. The developed eggs are lodged in the pedicel

  14. Observations on the Domestic Ecology of Rhodnius ecuadoriensis (Triatominae

    Directory of Open Access Journals (Sweden)

    Abad-Franch F

    2002-01-01

    Full Text Available Rhodnius ecuadoriensis infests peridomiciles and colonises houses in rural southern Ecuador. Six out of 84 dwellings (7% surveyed in a rural village were infested (78 bugs/infested domicile; 279 bugs were collected in a single dwelling. Precipitin tests revealed R. ecuadoriensis fed on birds (65%, rodents (31%, marsupials (8%, and humans (15% - mixed bloodmeals detected in 37.5% of individual samples. Trypanosoma cruzi from opossums and rodents may thus be introduced into the domestic cycle. Wasp parasitoidism was detected in 6.5% of 995 R. ecuadoriensis eggs (only in peridomestic habitats. Control strategies should integrate insecticide spraying (indoors and peridomestic, better management of poultry, and housing improvements. A possible inefficacy of Malathion is reported.

  15. Chagas' disease in the Amazon Basin: V. Periurban palms as habitats of Rhodnius robustus and Rhodnius pictipes - triatomine vectors of Chagas' disease

    Directory of Open Access Journals (Sweden)

    M. A. Miles

    1983-12-01

    Full Text Available Trypanosoma cruzi infected Rhodnius robustus and/or Rhodnius pictipes were commonly found, in large numbers, in the Brazilian Amazonian palms Maximiliana regia ("inajá", Acrocomia sclerocarpa ("mucajá" and Orbignya speciosa ("babaçu". The common opossum, Didelphis marsupialis, was the animal most frequently associated with triatomine infested palms. R. pictipes, frequently light-attracted into houses from palm trees, was the probable source of an acute case of Chagas' disease in the vicinity of Belém. It is considered that triatomine infested palms are likely to cause some cases of acute Chagas' disease in the States of Amazonas and Rondônia. Possible control methods are suggested.Rhodnius robustus e/ou Rhodnius pictipes, infectados com Trypanosoma cruzi foram comumente encontrados, em grande numero, nas palmeiras Maximiliana regia (inaja, Acrocomia sclerocarpa (mucaja e Orbignya speciosa (babacu na Amazonia brasileira. O marsupial Didelphis marsupialis foi o animal encontrado mais frequentemente nas palmeiras associadas a alta prevalencia de triatomineos. R. pictipes que e atraido pela luz nas residencias de palmeiras vizinhas, provavelmente e a fonte de um caso agudo de doenca de Chagas nas vizinhancas de Belem. Sugere-se que as palmeiras albergando triatomineos poderiam ser relacionadas com infeccoes humanas de doenca de Chagas nos Estados de Amazonas e Rondonia. Sugere-se, tambem, possiveis metodos de controle.

  16. Silencing of RpATG6 impaired the yolk accumulation and the biogenesis of the yolk organelles in the insect vector R. prolixus.

    Directory of Open Access Journals (Sweden)

    Priscila H Vieira

    2018-05-01

    Full Text Available In oviparous animals, the egg yolk is synthesized by the mother in a major metabolic challenge, where the different yolk components are secreted to the hemolymph and delivered to the oocytes mostly by endocytosis. The yolk macromolecules are then stored in a wide range of endocytic-originated vesicles which are collectively referred to as yolk organelles and occupy most of the mature oocytes cytoplasm. After fertilization, the contents of these organelles are degraded in a regulated manner to supply the embryo cells with fundamental molecules for de novo synthesis. Yolk accumulation and its regulated degradation are therefore crucial for successful development, however, most of the molecular mechanisms involved in the biogenesis, sorting and degradation of targeted yolk organelles are still poorly understood. ATG6 is part of two PI3P-kinase complexes that can regulate the recruitment of the endocytic or the autophagy machineries. Here, we investigate the role of RpATG6 in the endocytosis of the yolk macromolecules and in the biogenesis of the yolk organelles in the insect vector Rhodnius prolixus. We found that vitellogenic females express high levels of RpATG6 in the ovaries, when compared to the levels detected in the midgut and fat body. RNAi silencing of RpATG6 resulted in yolk proteins accumulated in the vitellogenic hemolymph, as a consequence of poor uptake by the oocytes. Accordingly, the silenced oocytes are unviable, white (contrasting to the control pink oocytes, smaller (62% of the control oocyte volume and accumulate only 40% of the yolk proteins, 80% of the TAG and 50% of the polymer polyphosphate quantified in control oocytes. The cortex of silenced oocytes present atypical smaller vesicles indicating that the yolk organelles were not properly formed and/or sorted, which was supported by the lack of endocytic vesicles near the plasma membrane of silenced oocytes as seen by TEM. Altogether, we found that RpATG6 is central for the

  17. Efecto insecticida del extracto de semillas de Neem (Azadirachta indica sobre Collaria scenica, Stal (Hemiptera: Miridae

    Directory of Open Access Journals (Sweden)

    Daniel Villamil Montero

    2012-07-01

    Abstract. This work was developed with the objetive to evaluate the insecticidal effect of the Neem (Azadirachta indica A. Juss seeds against grass bug nymphs Collaria scenica Stal. For that, an extract was prepared from green fruits of Neem by rotaevaporación. The extract was diluted in three ppm concentrations corresponding to treatments. Using thin-layer chromatography we identified the presence of Azaridactina. DCA essay was carried out with 4 treatments and 5 repetitions that included the three extract concentrations and a control. In each repetition were used 15 nymphs, randomly placed in plastic boxes with food and the corresponding concentration. Every day an extract application was made and recorded mortality percentage, number of exuviae and number of individuals who came to adulthood in each treatment. The results were analyzed using Kruskal-Wallis and Games-Howell for each variable. The three concentrations of Neem seed extract had a negative effect on the development of the bugs. The more concentrated treatment (250 ppm was the most effective, showing a 97% mortality, fewer exuvias and and fewer adults in the end of the experiment.

  18. Description and characterization of the melanic morphotype of Rhodnius nasutus Stål, 1859 (Hemiptera: Reduviidae: Triatominae

    Directory of Open Access Journals (Sweden)

    Fernando Braga Stehling Dias

    2014-10-01

    Full Text Available Introduction For the first time we provide the description of the melanic (dark morphotype of Rhodnius nasutus and determine the pattern of genetic inheritance for this characteristic. Methods Dark morph R. nasutus specimens were crossbred with standard (typically patterned R. nasutus. Results We present the first occurrence of the melanic morphotype in the genus Rhodnius. The crossbreeding results demonstrate that the inheritance pattern of this characteristic follows Mendel's simple laws of segregation and an independent assortment of alleles. Conclusions Phenotypic variation of R. nasutus reinforces the heterogeneity found in the Triatominae. Descriptions of new species in this subfamily require rigorous validation criteria.

  19. Evaluasi Sifat Ovisidal dan Nimfasidal Insektisida Buprofezin 100 g/l terhadap Telur dan Nimfa Wereng Coklat, Nilaparvata lugens (Stal.) (Hemiptera: Delphacidae)

    OpenAIRE

    BAEHAKI SUHERLAN EFFENDI; EKO HARI ISWANTO; AMIR HAMZAH

    2016-01-01

    Evaluation of ovicidal and nymphcidal properties of buprofezin 100 g/linsecticide to eggs and nymphs of brown planthopper, Nilaparvata lugens(Stal.) (Hemiptera: Delphacidae). Research was carried out in screen house ofSukamandi, Indonesian Center for Rice Research (ICRR) in the wet season of 2013. Theresearch used randomized block design with 5 doses levels insecticide treatment of buprofezin100 g/l and four replications. The buprofezin treatments were 250, 500, 750, 1000, and 1500ml/ha compa...

  20. Influência da temperatura e umidade no desenvolvimento ninfal de Rhodnius robustus Influence of temperature and humidity on the nymphal development of Rhodnius robustus

    Directory of Open Access Journals (Sweden)

    Dayse da S Rocha

    2001-08-01

    Full Text Available OBJETIVO: Avaliar as diferenças significativas de desenvolvimento ninfal da espécie Rhodnius robustus Larrousse, 1927, submetida a diferentes condições de temperatura e umidade, que se encontra distribuída na região Norte do Brasil (Acre, Amazonas e Pará e na Colômbia, no Equador, no Peru e na Venezuela. MÉTODOS: Formaram-se três grupos de Rhodnius robustus, mantidos em diferentes condições de laboratório: 33/40 (33+/-1°C e 40+/-5% UR -- umidade relativa, 33/70 (33+/-1°C e 70+/-5% UR e 28/70 (28+/-1°C e 70+/-5% UR, para observar o período de incubação dos ovos, o desenvolvimento de cada estádio, os percentuais de mortalidade e os número de repastos realizados. RESULTADOS: O menor período médio de desenvolvimento ninfal foi observado no grupo 28/70 com as médias: 14,4; 17,3; 20,3; 22,8 e 40. O desenvolvimento embrionário apresentou diferenças significativas entre os tratamentos utilizados (pOBJECTIVE: To assess the significant differences in the nymphal development of the Rhodnius robustus Larrousse, 1927 under different temperatures and humidity conditions. This is a species found in the northern region of Brazil (states of Acre, Amazonas, and Pará, Colombia, Equator, Peru and Venezuela. METHODS: Three groups of triatominae were kept under the following laboratory conditions: 33/40 (33+1°C and 40+/-5% of relative humidity -- RH, 33/70 (33+/-1°C and 70+/-5% RH, and 28/70 (28+/-1°C and 70+/-5% RH. The incubation period of the eggs, developmental time of each stage, mortality percentage, number of bloodmeals, and the total amount of time from the egg hatching to adult ecdysis were observed. RESULTS: The shortest average time of nymphal development was observed in the 28/70 group, with following averages: 14.4, 17.3, 20.3, 22.8, and 40. Significant differences were observed in the embryonic development between the groups (p<0.01. For all groups, the number of bloodmeals had a gradual increase near the adult phase

  1. Genetic, cytogenetic and morphological trends in the evolution of the Rhodnius (Triatominae: Rhodniini) trans-Andean group.

    Science.gov (United States)

    Díaz, Sebastián; Panzera, Francisco; Jaramillo-O, Nicolás; Pérez, Ruben; Fernández, Rosina; Vallejo, Gustavo; Saldaña, Azael; Calzada, Jose E; Triana, Omar; Gómez-Palacio, Andrés

    2014-01-01

    The Rhodnius Pacific group is composed of three species: Rhodnius pallescens, R. colombiensis and R. ecuadoriensis, which are considered important vectors of trypanosomes (Trypanosoma cruzi and T. rangeli) infecting humans. This group is considered as a recent trans-Andean lineage derived from the widespread distributed sister taxa R. pictipes during the later uplift of northern Andes mountain range. The widest spread species R. pallescens may be a complex of two divergent lineages with different chromosomal attributes and a particular biogeographical distribution across Central America and Colombia with several southern populations in Colombia occupying the same sylvatic habitat as its sister species R. colombiensis. Although the taxonomy of Rhodnius Pacific group has been well studied, the unresolved phylogenetic and systematic issues are the target of this paper. Here we explore the molecular phylogeography of this species group analyzing two mitochondrial (ND4 and cyt b) and one nuclear (D2 region of ribosomal 28S gene) gene sequences. The molecular analyses suggest an early divergence of the species R. ecuadoriensis and R. colombiensis, followed by a recent expansion of R. pallescens lineages. The phylogenetic relationship between sympatric R. pallescens Colombian lineage and R. colombiensis was further explored using wing morphometry, DNA genome size measurements, and by analyzing chromosomal behavior of hybrids progeny obtained from experimental crosses. Our results suggest that the diversification of the two R. pallescens lineages was mainly influenced by biogeographical events such as (i) the emergence of the Panama Isthmus, while the origin and divergence of R. colombiensis was associated with (ii) the development of particular genetic and chromosomal features that act as isolation mechanisms from its sister species R. pallescens (Colombian lineage). These findings provide new insights into the evolution of the Rhodnius Pacific group and the underlying

  2. Induction of insect plant resistance to the spittlebug Mahanarva fimbriolata Stal (Hemiptera: Cercopidae) in sugarcane by silicon application

    International Nuclear Information System (INIS)

    Korndorfer, A.P.; Grisoto, E.; Vendramim, J.D.

    2011-01-01

    Changes in the agroecosystem with the increase of green cane harvesting in Brazil affected the insect populations associated to this crop, and secondary pests like the spittlebug Mahanarva fimbriolata Stal, became much more important. Many studies have demonstrated the active role played by silicon in plant defense against herbivory. The objective of this study was to evaluate the effects of silicon applications on the biology of the spittlebug reared on two resistant (SP79-1011 and SP80-1816) and one susceptible (SP81-3250) sugarcane cultivars. Sugarcane plants were grown under greenhouse conditions and submitted to different treatments: with and without silicon fertilizer in two different soil type (sandy and clay soil). The newly hatched nymphs were transferred to sugarcane roots and placed into boxes with lids, to keep a moistened and dark environment favoring their growth and maintenance of the root system, providing food access to the developing nymphs. After emergence, adult males and females were placed in cages for mating and oviposition. The silicon absorbed and accumulated in the plant caused an increase in nymphal mortality, and depending on the sugarcane cultivar tested this element also provided an increase in the duration of the nymphal stage and a decrease in the longevity of males and females. 'SP79-1011' presented the highest silicon content in leaves, and M. fimbriolata had the highest nymph mortality and the shortest female longevity. The pre-oviposition period, fecundity and egg viability were not affected by the silicon content in plants or the cultivar used. (author)

  3. Induction of insect plant resistance to the spittlebug Mahanarva fimbriolata Stal (Hemiptera: Cercopidae) in sugarcane by silicon application

    Energy Technology Data Exchange (ETDEWEB)

    Korndorfer, A.P.; Grisoto, E.; Vendramim, J.D., E-mail: korndorfer@hotmail.co [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Entomologia e Acarologia

    2011-05-15

    Changes in the agroecosystem with the increase of green cane harvesting in Brazil affected the insect populations associated to this crop, and secondary pests like the spittlebug Mahanarva fimbriolata Stal, became much more important. Many studies have demonstrated the active role played by silicon in plant defense against herbivory. The objective of this study was to evaluate the effects of silicon applications on the biology of the spittlebug reared on two resistant (SP79-1011 and SP80-1816) and one susceptible (SP81-3250) sugarcane cultivars. Sugarcane plants were grown under greenhouse conditions and submitted to different treatments: with and without silicon fertilizer in two different soil type (sandy and clay soil). The newly hatched nymphs were transferred to sugarcane roots and placed into boxes with lids, to keep a moistened and dark environment favoring their growth and maintenance of the root system, providing food access to the developing nymphs. After emergence, adult males and females were placed in cages for mating and oviposition. The silicon absorbed and accumulated in the plant caused an increase in nymphal mortality, and depending on the sugarcane cultivar tested this element also provided an increase in the duration of the nymphal stage and a decrease in the longevity of males and females. 'SP79-1011' presented the highest silicon content in leaves, and M. fimbriolata had the highest nymph mortality and the shortest female longevity. The pre-oviposition period, fecundity and egg viability were not affected by the silicon content in plants or the cultivar used. (author)

  4. Resistance to starvation of Rhodnius neivai Lent, 1953 (Hemiptera: Reduviidae: Triatominae under experimental conditions

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    Daniel R Cabello

    2001-05-01

    Full Text Available The period of resistance to starvation and the loss of weight until death of Rhodnius neivai in all stages of development were studied. Work was based on experiments conducted under controlled laboratory conditions. One hundred specimens of each nymphal instar were observed: 50 were fed on chicken and 50 on rabbit. Adult females and males were kept together and fed on each host. All bugs were weighed weekly until death. Laid eggs were collected weekly and observed during five weeks to obtain hatchability. Resistance to starvation was similar with both hosts and increased with the evolutionary stage, excepting the 5th nymphal instar and adults. With both hosts, loss of weight was abrupt in the first week and steady in the following weeks. In adults, on the first weeks after eating, there was little or no mortality, after which mortality increased rapidly with the starving time. Reproductive output was higher in the bugs fed on rabbit. R. neivai is among the least resistant triatomine species.

  5. Alpinia Essential Oils and Their Major Components against Rhodnius nasutus, a Vector of Chagas Disease

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    Thamiris de A. de Souza

    2018-01-01

    Full Text Available Species of the genus Alpinia are widely used by the population and have many described biological activities, including activity against insects. In this paper, we describe the bioactivity of the essential oil of two species of Alpinia genus, A. zerumbet and A. vittata, against Rhodnius nasutus, a vector of Chagas disease. The essential oils of these two species were obtained by hydrodistillation and analyzed by GC-MS. The main constituent of A. zerumbet essential oil (OLALPZER was terpinen-4-ol, which represented 19.7% of the total components identified. In the essential oil of A. vittata (OLALPVIT the monoterpene β-pinene (35.3% was the main constituent. The essential oils and their main constituents were topically applied on R. nasutus fifth-instar nymphs. In the first 10 min of application, OLALPVIT and OLALPZER at 125 μg/mL provoked 73.3% and 83.3% of mortality, respectively. Terpinen-4-ol at 25 μg/mL and β-pinene at 44 μg/mL provoked 100% of mortality. The monitoring of resistant insects showed that both essential oils exhibited antifeedant activity. These results suggest the potential use of A. zerumbet and A. vittata essential oils and their major constituents to control R. nasutus population.

  6. Phenotypic variability of Rhodnius ecuadoriensis populations at the Ecuadorian central and southern Andean region.

    Science.gov (United States)

    Villacís, Anita G; Grijalva, Mario J; Catalá, Silvia S

    2010-11-01

    Rhodnius ecuadoriensis is an important vector of Chagas disease in Ecuador. Whereas only sylvatic and peridomestic populations are common in Manabi province, this species occupies domestic, peridomestic, and sylvatic habitats in Loja province where high reinfestation of houses was observed. To explore the existence of phenetic changes linked to the domiciliation of the species, this study set out to analyze the wing and antennal phenotypes of R. ecuadoriensis in these two provinces where the vector presents different affinity for domestic habitats. The antennal phenotype and the wing size and shape distinguish the two geographical populations of R. ecuadoriensis. In Manabí, sylvatic and peridomestic specimens were very similar. In Loja, sylvatic and nonsylvatic (domestic and peridomestic) populations showed distinctive characteristics. Remarkable sexual dimorphism of wing and antenna, exclusive of domestic specimens, and high metric disparity in the wing shape of the domestic females point out the existence of a particular situation in this habitat. The results of this phenotypic analysis and previous evidence of behavioral differences support the hypothesis of disruptive selection acting upon R. ecuadoriensis populations.

  7. Presence of Rhodnius ecuadoriensis in sylvatic habitats in the southern highlands (Loja Province) of Ecuador.

    Science.gov (United States)

    Grijalva, M J; Villacis, A G

    2009-05-01

    The main vectors of Chagas disease in Ecuador are Triatoma dimidiata and Rhodnius ecuadoriensis. The latter species occupies domestic and peridomestic habitats, as well as sylvatic ecotopes--particularly associated with Phytelephas aequatorialis palm trees--in the western coastal region of Ecuador. In the southern highlands, however, such palm tree habitats are uncommon, and sylvatic populations of R. ecuadoriensis have not previously been reported to date. This study was carried out in five rural communities in Loja Province in southern Ecuador, where manual triatomine searches were conducted in various sylvatic habitats. A total of 81 squirrel nests (Sciurus stramineus) and > 200 bird nests and other habitats were searched. One hundred three R. ecuadoriensis individuals were found in 11 squirrel nests (infestation index = 13.6%, density = 2 bugs per nest searched, crowding = 9.5 bugs per infested nest, colonization index = 72.7% of infested nests with nymphs). No triatomines were found in bird nests or other sylvatic habitats. The presence of sylvatic R. ecuadoriensis in the southern highlands of Ecuador has important implications for the long-term control of Chagas disease in the region because of the possibility of reinfestation of dwellings after insecticide-based control interventions.

  8. A Deep Insight into the Sialome of Rhodnius neglectus, a Vector of Chagas Disease.

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    Paula Beatriz Santiago

    2016-04-01

    Full Text Available Triatomines are hematophagous insects that act as vectors of Chagas disease. Rhodnius neglectus is one of these kissing bugs found, contributing to the transmission of this American trypanosomiasis. The saliva of hematophagous arthropods contains bioactive molecules responsible for counteracting host haemostatic, inflammatory, and immune responses.Next generation sequencing and mass spectrometry-based protein identification were performed to investigate the content of triatomine R. neglectus saliva. We deposited 4,230 coding DNA sequences (CDS in GenBank. A set of 636 CDS of proteins of putative secretory nature was extracted from the assembled reads, 73 of them confirmed by proteomic analysis. The sialome of R. neglectus was characterized and serine protease transcripts detected. The presence of ubiquitous protein families was revealed, including lipocalins, serine protease inhibitors, and antigen-5. Metalloproteases, disintegrins, and odorant binding protein families were less abundant.The data presented improve our understanding of hematophagous arthropod sialomes, and aid in understanding hematophagy and the complex interplay among vectors and their vertebrate hosts.

  9. The effect of Ageratum fastigiatum extract on Rhodnius nasutus, vector of Chagas disease

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    Bethânia A. Avelar-Freitas

    2013-04-01

    Full Text Available Control of Chagas disease is based on insecticide spraying in domiciles in order to exterminate triatomine populations. However, since the vectors differ in susceptibility to currently used insecticides, the screening of the toxic potential of Brazilian flora may identify new molecules lethal to triatomines. This study evaluated the toxicity of ethanolic extract of Ageratum fastigiatum (Gardner R.M. King & H. Rob., Asteraceae, on Rhodnius nasutus, a known vector of Chagas disease. Ethanolic extracts of the aerial parts of A. fastigiatum were prepared at 25 and 50 mg/mL concentrations, and 5 µL was applied to fifth-instar nymphs of R. nasutus (n=30. Controls included nymphs that were treated with 5 µL ethanol (n=30 or left untreated (n=30. The percentage of dead insects in each group was observed at 24, 48, 72, 96 and 120 h after application. The extracts of A. fastigiatum showed a mortality rate of about 37% and 77% after 120 h, at concentrations of 25 and 50 mg/mL, respectively. In control groups, the mortality rate remained under 7%. The extract of A. fastigiatum contains a coumarin, a molecule with recognized toxicity in insects, and which may be responsible for killing the triatomines.

  10. Climatic factors and populational dynamics of Mahanarva posticata (Stal-1855) (Homoptera-Cercopidae) as a contribution to a possible regional implantation of the sterile male technique

    International Nuclear Information System (INIS)

    Oliveira, M.L. de

    1981-01-01

    A field study on the population dynamics of M. posticata (STAL, 1855) (Homoptera-Cercopidae) was carried out from 1971 to 1978 under the ecological conditions prevailing in the Litoral-Mata-Sul Zone of Pernambuco, Brazil. The results indicated that maximal infestation of the sugar cane crops by the insect generally occured in June and in July, and it was dependent on rainfall, temperature and relative humidity. The population density of adults was decreased markedly during the months of January, February and March. Technical and economical viability of the insect control by the male-sterilization-techniques through radiation was also demonstrated. The technique is to be used isolated or with other conventional procedures in the combat of froghopper infestations in the sugar cane growing in Pernambuco, Brazil. (Author) [pt

  11. First report of Rhodnius stali (Hemiptera, Reduviidae, Triatominae in the State of Acre and in the Brazilian Amazon

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    Dionatas Ulises de Oliveira Meneguetti

    2016-06-01

    Full Text Available Abstract: INTRODUCTION: This paper reports, for the first time, the presence of Rhodnius stali in the state of Acre and in the Brazilian Amazon. METHODS: Specimens of R. stali were collected by the Federal University of Acre in Rio Branco. RESULTS: The number of Triatominae species in the State of Acre increased from five to six. This was also the first report of R. stali in the Brazilian Amazon. CONCLUSIONS: The occurrence of R. stali is worrisome, since this species has been found naturally infected by Trypanosoma cruzi and there has been evidence of its domiciliation capabilities.

  12. NOTA PRÉVIA SOBRE ALGUNS DADOS BIONÔMICOS DO PREDADOR DE ABELHAS Apiomerus nigrilobus Stal, 1872 OBTIDOS EM CONDIÇÕES DE LABORATÓRIO PRELIMINARY NOTE ON BIONOMIC DATA OF THE HONEYBEE PREDATOR Apiomerus nigrilobus STAL, 1872 GOTTEN IN LABORATORY CONDITIONS

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    Érico Amaral

    2007-09-01

    Full Text Available

    Esta nota prévia apresenta alguns dados bionômicos do predador de abelhas Apiomerus nigrilobus Stal, 1872 obtidos sob condições de laboratório. O estudo foi realizado no Departamento de Entomologia da Escola Superior de Agricultura “Luiz de Queiroz” da Universidade do Estado de São Paulo, no período de março de 1972 a dezembro de 1973. O ciclo biológico médico constatado para este predador foi de 246 dias. Os autores apresentam três quadros que resumem os dados obtidos.

    This preliminary note presents some bionomics data of the honeybee predator Apiomerus nigrilobus Stal, 1872 obtained in laboratory. The study was conducted at the Agricultural College ";Luiz de Queiroz” U.S.P. — São Pau1o, Brazil, from March 1972 to December 1973. The evolutionary cycle of this predator, on an average, is 246 days. A table is presented showing the results.

  13. Biocide activity of Annona coriacea seeds extract on Rhodnius neglectus (Hemiptera: Reduviidae

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    Ângela Pinheiro Carneiro

    2013-03-01

    Full Text Available The use of synthetic insecticides for insect control may lead to different kind of problems, such as vector resistance to insecticides. To avoid these problems, a new research area to study botanical products as possible disease vectors controls, has become a feasible alternative. The purpose of this research was to evaluate the biocide activity of the ethanol extract of seeds of Annona coriacea on Rhodnius neglectus (Chagas disease vector nymphs and adults. For this, different concentrations extracts were evaluated: 25, 50, 100 and 200mg/ mL, and water in DMSO (20% was used as control. The experimental design was completely randomized and we conducted the bioassay with nymphs and adults, with 10 nymphs and 10 adults (five males and five females per treatment. Extract action was evaluated in both bioassays, in order to identify possible effects of mortality and life cycle interruption of nymphs and adults during a 28-day-period. The results obtained showed that the extract of A. coriacea was able to disrupt the development of nymphs and adults of R. neglectus, with a mortality rate of more than 90%, 36% and 100%, at the highest concentrations, respectively. There was also molting inhibition in nymphs, lower reproductive capacity in females, feeding deterrence and morphological changes in nymphs and adults. We concluded that the extract of A. coriacea has insecticide action on nymphs and adults of R. neglectus.La enfermedad de Chagas se convirtió en un problema de salud debido a su importancia epidemiológica, es producida por el protista Trypanosoma cruzi, cuyos insectos vectores son del género Triatoma y Panstrongylus. El objetivo de este estudio fue evaluar la actividad biocida del extracto de Annona coriacea en las ninfas de Rhodnius neglectus y en sus adultos. Se evaluaron 14 concentraciones de 25, 50, 100 y 200mg/ml del extracto etanólico, así como el control, en este caso agua de DMSO (20%. Se utilizo un diseño completamente

  14. Estudo sobre a utilização de Rhodnius neglectus para xenodiagnósticos realizados em marsupiais (Didelphis The utilization of Rhodnius neglectus in xenodiagnosis: a study performed on opossums

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1976-12-01

    Full Text Available Em marsupiais (Didelphis, portadores de infecção natural pelo T. cruzi, procurou-se levar a efeito xenodiagnósticos com o emprego de ninfas de Rhodnius neglectus e de Triatoma infestans e através do exame periódico de lotes formados por cinco insetos. Pôde-se observar o melhor rendimento por parte do exame do intestino posterior, mediante dissecção. O tempo ótimo foi situado no intervalo correspondente a 15 e 20 dias, e a eficiência de R. neglectus foi superior. Esse resultado, aliado à facilidade de sua manutenção em laboratório, sugere a utilização rotineira desse triatomíneo para fins de xenodiagnóstico.Third and fourth instars of Rhodnius neglectus and Triatoma infestans were fed on wild opossums (Didelphis with natural infeccions by Trypanosoma cruzi and, examined at regular 3.5 days intervals. Best results were obtained with rectum examinations and the infeccion was more easily detected from the 15th to the 20th days. R. neglectus showed better performance than T. infestans and so its utilisation in the xenodiagnosis technique is suggested.

  15. Ecological factors related to the widespread distribution of sylvatic Rhodnius ecuadoriensis populations in southern Ecuador

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    Grijalva Mario J

    2012-01-01

    Full Text Available Abstract Background Chagas disease transmission risk is a function of the presence of triatomines in domestic habitats. Rhodnius ecuadoriensis is one of the main vectors implicated in transmission of Trypanosoma cruzi in Ecuador. This triatomine species is present in domestic, peridomestic and sylvatic habitats in the country. To determine the distribution of sylvatic populations of R. ecuadoriensis and the factors related to this distribution, triatomine searches were conducted between 2005 and 2009 in southern Ecuador. Methods Manual triatomine searches were conducted by skilled bug collectors in 23 communities. Sylvatic searched sites were selected by a directed sampling, where microhabitats were selected by the searchers and b random sampling, where sampling points where randomly generated. Domiciliary triatomine searches were conducted using the one man-hour method. Natural trypanosome infection was determined by microscopic examination and PCR. Generalized linear models were used to test the effect of environmental factors on the presence of sylvatic triatomines. Results In total, 1,923 sylvatic individuals were collected representing a sampling effort of 751 man-hours. Collected sylvatic triatomines were associated with mammal and bird nests. The 1,219 sampled nests presented an infestation index of 11.9%, a crowding of 13 bugs per infested nest, and a colonization of 80% of the nests. Triatomine abundance was significantly higher in squirrel (Sciurus stramineus nests located above five meters from ground level and close to the houses. In addition, 8.5% of the 820 examined houses in the same localities were infested with triatomines. There was a significant correlation between R. ecuadoriensis infestation rates found in sylvatic and synanthropic environments within communities (p = 0.012. Parasitological analysis revealed that 64.7% and 15.7% of the sylvatic bugs examined (n = 300 were infected with Trypanosoma cruzi and T. rangeli

  16. Ecological factors related to the widespread distribution of sylvatic Rhodnius ecuadoriensis populations in southern Ecuador

    Science.gov (United States)

    2012-01-01

    Background Chagas disease transmission risk is a function of the presence of triatomines in domestic habitats. Rhodnius ecuadoriensis is one of the main vectors implicated in transmission of Trypanosoma cruzi in Ecuador. This triatomine species is present in domestic, peridomestic and sylvatic habitats in the country. To determine the distribution of sylvatic populations of R. ecuadoriensis and the factors related to this distribution, triatomine searches were conducted between 2005 and 2009 in southern Ecuador. Methods Manual triatomine searches were conducted by skilled bug collectors in 23 communities. Sylvatic searched sites were selected by a) directed sampling, where microhabitats were selected by the searchers and b) random sampling, where sampling points where randomly generated. Domiciliary triatomine searches were conducted using the one man-hour method. Natural trypanosome infection was determined by microscopic examination and PCR. Generalized linear models were used to test the effect of environmental factors on the presence of sylvatic triatomines. Results In total, 1,923 sylvatic individuals were collected representing a sampling effort of 751 man-hours. Collected sylvatic triatomines were associated with mammal and bird nests. The 1,219 sampled nests presented an infestation index of 11.9%, a crowding of 13 bugs per infested nest, and a colonization of 80% of the nests. Triatomine abundance was significantly higher in squirrel (Sciurus stramineus) nests located above five meters from ground level and close to the houses. In addition, 8.5% of the 820 examined houses in the same localities were infested with triatomines. There was a significant correlation between R. ecuadoriensis infestation rates found in sylvatic and synanthropic environments within communities (p = 0.012). Parasitological analysis revealed that 64.7% and 15.7% of the sylvatic bugs examined (n = 300) were infected with Trypanosoma cruzi and T. rangeli respectively, and 8% of the

  17. Comportamiento de Rhodnius robustus Larousse, 1927 (Hemiptera, Reduviidae durante su alimentación en condiciones de laboratorio

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    Camilo Rubio

    2013-06-01

    Full Text Available Introducción. A pesar del control de los insectos domiciliados, se siguen presentando casos de enfermedad de Chagas con la participación en la transmisión de especies peridomiciliarias y selváticas,una de las cuales es Rhodnius robustus, especie reportada con infecciones naturales de Trypanosoma cruzi y T. rangeli. Objetivo. Describir el comportamiento de R. robustus durante su alimentación en condiciones delaboratorio.Materiales y métodos. En cada estadio de desarrollo de R. robustus se analizó el tiempo promedio para alcanzar la repleción, número promedio de deyecciones, porcentaje de individuos que defecan durante la comida y ganancia de peso después de la alimentación. Resultados. Rhodnius robustus tardó entre 19:26 y 44:55 (minutos:segundos en alimentarse arepleción; los insectos defecaron en todos sus diferentes estadios durante la alimentación. El porcentaje de individuos que defecan durante la alimentación varía de 13,3 % a 93,3 %. Por otro lado, el consumo promedio de sangre en el quinto estadio, 337,19 mg, duplica la cantidad ingerida por los adultos, 161,25 mg. Conclusiones. En todos los estadios de R. robustus hay defecación durante la alimentación, factor que favorece su competencia vectorial. Sin embargo, el tiempo para la primera deyección, el porcentaje dedeyecciones y los individuos que defecan durante la comida, así como la cantidad de sangre ingerida, varían entre los estadios, lo cual indica que el comportamiento alimenticio está mediado por variables dependientes de la edad/estadio.   http://dx.doi.org/10.7705/biomedica.v33i2.743

  18. Evaluasi Sifat Ovisidal dan Nimfasidal Insektisida Buprofezin 100 g/l terhadap Telur dan Nimfa Wereng Coklat, Nilaparvata lugens (Stal. (Hemiptera: Delphacidae

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    BAEHAKI SUHERLAN EFFENDI

    2016-11-01

    Full Text Available Evaluation of ovicidal and nymphcidal properties of buprofezin 100 g/linsecticide to eggs and nymphs of brown planthopper, Nilaparvata lugens(Stal. (Hemiptera: Delphacidae. Research was carried out in screen house ofSukamandi, Indonesian Center for Rice Research (ICRR in the wet season of 2013. Theresearch used randomized block design with 5 doses levels insecticide treatment of buprofezin100 g/l and four replications. The buprofezin treatments were 250, 500, 750, 1000, and 1500ml/ha compared with control without insecticide. The objective of the research to evaluate ofovicidal and nymphcidal of buprofezin to brown planthopper (BPH. The results showed thatthe ovicidal properties of buprofezin 100 g/l with a range doses of treatments to BPH eggsthat application at 5 days after inoculation with eggs remains in the plant tissue were 39,79-94,88%. The raising ovicidal of buprofezin were 74,84-99,5% that applied at 9 days afterinoculation with eggs remains in the plant tissue. In the other hand the ovicidal properties ofbuprofezin decreased dramatically were 20-48% that applied at 5 days after inoculation andthen BPH eggs removed from plant tissue (dissected at 9 days after inoculation. The higherovicidal properties of buprofezin is better in the plant tissue than in the dissected eggs treated,because buprofezin working on eggs in plant tissue as a systemic insecticide. The dissectedBPH eggs of rice treated to show the normal eggs shape and no eggs contracted. Theunhatched eggs of buprofezin treatments were milk white due to insecticide effect, sometranslucent color with a red dot as a fertile eggs or without a red dot as unfertile eggs.Buprofezin was the excellent nymphcidal insecticide with the value of the efficacy to BPHnymphs were very high about 87,44 -100% for a range doses treatments. Buprofezin did notresurgence effect, moreover this insecticides still have ovicidal and nimphcidal properties as abasic to reduce offspring of brown planthopper.

  19. Effects of environmental temperature on life tables of Rhodnius neivai Lent, 1953 (Hemiptera: Reduviidae under experimental conditions

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    Daniel R Cabello

    1999-09-01

    Full Text Available Changes in life tables of Rhodnius neivai due to variations of environmental temperature were studied, based on nine cohorts. Three cohorts were kept at 22°C, three at 27°C and three at 32°C. Cohorts were censused daily during nymphal instars and weekly in adults. Nine complete horizontal life tables were built. A high negative correlation between temperature and age at first laying was registered (r=-0,84. Age at maximum reproduction was significantly lower at 32°C. Average number of eggs/female/week and total eggs/female on its life time were significantly lower at 22°C. Total number of egg by cohort and total number of reproductive weeks were significantly higher at 27°C. At 32°C, generational time was significantly lower. At 27°C net reproductive rate and total reproductive value were significantly higher. At 22°C, intrinsic growth, finite growth and finite birth rates were significantly lower. At 22°C, death instantaneous rate was significantly higher.

  20. Trypanosoma cruzi-infected Panstrongylus geniculatus and Rhodnius robustus adults invade households in the Tropics of Cochabamba region of Bolivia.

    Science.gov (United States)

    Rojas-Cortez, Mirko; Pinazo, Maria-Jesus; Garcia, Lineth; Arteaga, Mery; Uriona, Liliana; Gamboa, Seyla; Mejía, Carolina; Lozano, Daniel; Gascon, Joaquim; Torrico, Faustino; Monteiro, Fernando A

    2016-03-16

    There are hardly any data available on the relationships between the parasite and the vector or regarding potential reservoirs involved in the natural transmission cycle of Trypanosoma cruzi in the Tropics of Cochabamba, Bolivia. Local families from communities were responsible for the capture of triatomine specimens, following a strategic methodology based on entomological surveillance with community participation developed by the National Chagas Programme of the Ministry of Health of Bolivia. We describe the collection of adult Panstrongylus geniculatus and Rhodnius robustus naturally infected with Trypanosoma cruzi from houses and from the hospital of Villa Tunari municipality. The flagellates found in the digestive tract of P. geniculatus belong to genetic lineages or DTUs TcI and TcIII, whereas only lineage DTU TcI was found in R. robustus. The detection of these vectors infected with T. cruzi reveals the vulnerability of local communities. The results presented here highlight the risk of Chagas disease transmission in a region previously thought not to be endemic, indicating that the Tropics of Cochabamba should be placed under permanent entomological and epidemiological surveillance.

  1. The Triatomines of Northern Peru, with Emphasis on the Ecology and Infection by Trypanosomes of Rhodnius ecuadoriensis (Triatominae

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    Cuba Cuba César A

    2002-01-01

    Full Text Available Information on the distribution and synanthropic behaviour of triatomines is essential for Chagas disease vector control. This work summarises such information from northern Peru, and presents new data on Rhodnius ecuadoriensis - an important local vector infesting 10-35% of dwellings in some zones. Three species are strongly synanthropic and may be suitable targets for chemical control of domestic/peridomestic bug populations. Panstrongylus herreri, the main domestic vector in the area, is probably present in sylvatic ecotopes in the Marañón river system. R. ecuadoriensis and Triatoma dimidiata seem exclusively domestic; biogeographical and ecological data suggest they might have spread in association with humans in northern Peru. Confirmation of this hypothesis would result in a local eradication strategy being recommended. Presence of trypanosome natural infection was assessed in 257 R. ecuadoriensis; Trypanosoma rangeli was detected in 4% of bugs. Six further triatomine species are potential disease vectors in the region (T. carrioni, P. chinai, P. rufotuberculatus, P. geniculatus, R. pictipes, and R. robustus, whilst Eratyrus mucronatus, E. cuspidatus, Cavernicola pilosa, Hermanlentia matsunoi, and Belminus peruvianus have little or no epidemiological significance. A strong community-based entomological surveillance system and collaboration with Ecuadorian public health authorities and researchers are recommended.

  2. 2b-RAD genotyping for population genomic studies of Chagas disease vectors: Rhodnius ecuadoriensis in Ecuador.

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    Luis E Hernandez-Castro

    2017-07-01

    Full Text Available Rhodnius ecuadoriensis is the main triatomine vector of Chagas disease, American trypanosomiasis, in Southern Ecuador and Northern Peru. Genomic approaches and next generation sequencing technologies have become powerful tools for investigating population diversity and structure which is a key consideration for vector control. Here we assess the effectiveness of three different 2b restriction site-associated DNA (2b-RAD genotyping strategies in R. ecuadoriensis to provide sufficient genomic resolution to tease apart microevolutionary processes and undertake some pilot population genomic analyses.The 2b-RAD protocol was carried out in-house at a non-specialized laboratory using 20 R. ecuadoriensis adults collected from the central coast and southern Andean region of Ecuador, from June 2006 to July 2013. 2b-RAD sequencing data was performed on an Illumina MiSeq instrument and analyzed with the STACKS de novo pipeline for loci assembly and Single Nucleotide Polymorphism (SNP discovery. Preliminary population genomic analyses (global AMOVA and Bayesian clustering were implemented. Our results showed that the 2b-RAD genotyping protocol is effective for R. ecuadoriensis and likely for other triatomine species. However, only BcgI and CspCI restriction enzymes provided a number of markers suitable for population genomic analysis at the read depth we generated. Our preliminary genomic analyses detected a signal of genetic structuring across the study area.Our findings suggest that 2b-RAD genotyping is both a cost effective and methodologically simple approach for generating high resolution genomic data for Chagas disease vectors with the power to distinguish between different vector populations at epidemiologically relevant scales. As such, 2b-RAD represents a powerful tool in the hands of medical entomologists with limited access to specialized molecular biological equipment.

  3. Pioneer study of population genetics of Rhodnius ecuadoriensis (Hemiptera: Reduviidae) from the central coastand southern Andean regions of Ecuador.

    Science.gov (United States)

    Villacís, Anita G; Marcet, Paula L; Yumiseva, César A; Dotson, Ellen M; Tibayrenc, Michel; Brenière, Simone Frédérique; Grijalva, Mario J

    2017-09-01

    Effective control of Chagas disease vector populations requires a good understanding of the epidemiological components, including a reliable analysis of the genetic structure of vector populations. Rhodnius ecuadoriensis is the most widespread vector of Chagas disease in Ecuador, occupying domestic, peridomestic and sylvatic habitats. It is widely distributed in the central coast and southern highlands regions of Ecuador, two very different regions in terms of bio-geographical characteristics. To evaluate the genetic relationship among R. ecuadoriensis populations in these two regions, we analyzed genetic variability at two microsatellite loci for 326 specimens (n=122 in Manabí and n=204 in Loja) and the mitochondrial cytochrome b gene (Cyt b) sequences for 174 individuals collected in the two provinces (n=73 and=101 in Manabí and Loja respectively). The individual samples were grouped in populations according to their community of origin. A few populations presented positive F IS, possible due to Wahlund effect. Significant pairwise differentiation was detected between populations within each province for both genetic markers, and the isolation by distance model was significant for these populations. Microsatellite markers showed significant genetic differentiation between the populations of the two provinces. The partial sequences of the Cyt b gene (578bp) identified a total of 34 haplotypes among 174 specimens sequenced, which translated into high haplotype diversity (Hd=0.929). The haplotype distribution differed among provinces (significant Fisher's exact test). Overall, the genetic differentiation of R. ecuadoriensis between provinces detected in this study is consistent with the biological and phenotypic differences previously observed between Manabí and Loja populations. The current phylogenetic analysis evidenced the monophyly of the populations of R. ecuadoriensis within the R. pallescens species complex; R. pallescens and R. colombiensis were more

  4. 2b-RAD genotyping for population genomic studies of Chagas disease vectors: Rhodnius ecuadoriensis in Ecuador.

    Science.gov (United States)

    Hernandez-Castro, Luis E; Paterno, Marta; Villacís, Anita G; Andersson, Björn; Costales, Jaime A; De Noia, Michele; Ocaña-Mayorga, Sofía; Yumiseva, Cesar A; Grijalva, Mario J; Llewellyn, Martin S

    2017-07-01

    Rhodnius ecuadoriensis is the main triatomine vector of Chagas disease, American trypanosomiasis, in Southern Ecuador and Northern Peru. Genomic approaches and next generation sequencing technologies have become powerful tools for investigating population diversity and structure which is a key consideration for vector control. Here we assess the effectiveness of three different 2b restriction site-associated DNA (2b-RAD) genotyping strategies in R. ecuadoriensis to provide sufficient genomic resolution to tease apart microevolutionary processes and undertake some pilot population genomic analyses. The 2b-RAD protocol was carried out in-house at a non-specialized laboratory using 20 R. ecuadoriensis adults collected from the central coast and southern Andean region of Ecuador, from June 2006 to July 2013. 2b-RAD sequencing data was performed on an Illumina MiSeq instrument and analyzed with the STACKS de novo pipeline for loci assembly and Single Nucleotide Polymorphism (SNP) discovery. Preliminary population genomic analyses (global AMOVA and Bayesian clustering) were implemented. Our results showed that the 2b-RAD genotyping protocol is effective for R. ecuadoriensis and likely for other triatomine species. However, only BcgI and CspCI restriction enzymes provided a number of markers suitable for population genomic analysis at the read depth we generated. Our preliminary genomic analyses detected a signal of genetic structuring across the study area. Our findings suggest that 2b-RAD genotyping is both a cost effective and methodologically simple approach for generating high resolution genomic data for Chagas disease vectors with the power to distinguish between different vector populations at epidemiologically relevant scales. As such, 2b-RAD represents a powerful tool in the hands of medical entomologists with limited access to specialized molecular biological equipment.

  5. COLONIZATION OF PALM TREES BY Rhodnius neglectus AND HOUSEHOLD AND INVASION IN AN URBAN AREA, ARAÇATUBA, SÃO PAULO STATE, BRAZIL

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    Vera Lúcia Cortiço Corrêa Rodrigues

    2014-06-01

    Full Text Available The objective of this study is to report on the colonization of palm trees by Rhodnius neglectus, its invasion in an urban area, in Araçatuba - São Paulo, and the control and surveillance measures that have been put in place. Domiciliary triatomine searches occurred in apartments upon the inhabitants' notification. The collected insects were identified and examined for natural infection and food sources with a precipitin test. To search the palm trees, tarps were used to cover the floor, and a “Munck” truck equipped with a tree-pruning device was utilized. Chemical control was performed with the utilization of a manual compression. In 2009, 81 specimens of Rhodnius neglectus were collected from the domiciles by the population. The precipitin test revealed a presence of human blood in 2.7% of the samples. Entomological studies were carried out in these domiciles and in those located within a radius of 200 meters. The search performed in the palm trees resulted in the capture of 882 specimens of triatomines, negative for tripanosomatids. Mechanical and chemical controls were carried out. New searches conducted in the palm trees in the same year resulted in the capture of six specimens. The mechanical and chemical controls of the palm trees, together with the population's work, proved to be effective, therefore preventing these insects' colonization of the city's domiciles.

  6. Diversity of anti-haemostatic proteins in the salivary glands of Rhodnius species transmitters of Chagas disease in the greater Amazon.

    Science.gov (United States)

    Bussacos, Ana C M; Nakayasu, Ernesto S; Hecht, Mariana M; Parente, Juliana A; Soares, Célia M A; Teixeira, Antônio R L; Almeida, Igor C

    2011-08-24

    The triatomines in the tribe Rhodniini are the main vectors of the Trypanosoma cruzi to humans in recent outbreaks of acute Chagas disease in the Amazon. These insects dwelling in palm trees do not colonize the human domicile. Their success to transmit the infection relies partially on the efficacy of their salivary gland apparatuses. Here we show the transcriptome of the Rhodnius brethesi and Rhodnius robustus salivary glands, comprising 56 and 122 clusters, respectively. Approximately one third of these clusters are described for the first time. The LC-MS/MS analysis identified 123 and 111 proteins in R. brethesi and R. robustus sialome, respectively. Noteworthy, lipocalin platelet aggregation inhibitors, inositol polyphosphate 5-phosphatases, and Kazal domain proteins, which are essential for the insect's successful acquisition of blood meals, were found in our analysis. Moreover, glutathione S transferase and antigen-5, which play roles in the insect's defense and resistance against insecticide, were also observed. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. The Afrotropical Miomantiscaffra Saussure 1871 and Miomantispaykullii Stal 1871: first records of alien mantid species in Portugal and Europe, with an updated checklist of Mantodea in Portugal (Insecta: Mantodea).

    Science.gov (United States)

    Marabuto, Eduardo

    2014-01-01

    The recent growing interest on the Mantodea fauna of southern Europe and Portugal in particular, has enabled the discovery of two geographically separated populations of hitherto unknown species in Europe. Analysis of specimens shows that they belong to two Afrotropical mantids: Miomantiscaffra Saussure, 1871 and Miomantispaykullii Stal, 1871, thus raising the number of known species in Europe to 39 and in Portugal to 11. While these are remarkable findings, they also represent the first alien mantis species recorded from this continent. As yet, these species appear to be confined to artificial humanised gardened areas but call for more attention to the problem of biological invasions and the need for better bio-security measures for the conservation of natural ecosystems. In the absence of recent revisionary work on the Mantodea of Portugal and given the need to provide an accessible identification tool, both a checklist and a key to species are provided for all species in the country.

  8. Killer stal kinozvezdoi / Mihhail Sidilin

    Index Scriptorium Estoniae

    Sidilin, Mihhail

    2003-01-01

    Dokumentaalse varjundiga mängufilm "Kandahar" ("Safar e Ghandehar") : stsenarist ja režissöör Mohsen Makhmalbaf : Iraan - Prantsusmaa 2001. Pikemalt näitlejana esinevast Hassan Tantai'st, kes on olnud poliitiline palgamõrvar

  9. Sensibilidad de diferentes especies de Rhodnius (Hemiptera, Reduviidae, Triatominae a una cepa brasileña de Trypanosoma rangeli (SC58/KP1-

    Directory of Open Access Journals (Sweden)

    Daniella Barreto-Santana

    2015-03-01

    Materiales y métodos. Se seleccionaron treinta ninfas de cada especie después de xenodiagnóstico artificial en sangre infectada con T. rangeli. Se examinaron periódicamente muestras de heces y hemolinfa. Los insectos con hemolinfas infectadas fueron alimentados en ratones a fin de comprobar la transmisión por picadura y posteriormente disecados para confirmar la infección de las glándulas salivales. Resultados. En Rhodnius pictipes se encontró un mayor porcentaje de infección intestinal que en las otras especies. Se detectaron epimastigotes y tripomastigotes en la hemolinfa de las cuatro especies, y se encontró que el parasitismo fue menor en las especies del linaje R. robustus. Rhodnius robustus y R. neglectus no transmitían T. rangeli a ratones por picadura: después de la disección, sus glándulas no estaban infectadas. Solo un espécimen de R. nasutus y dos de R. pictipes transmitieron el parásito por la picadura. La tasa de infección glandular fue de 16 % para R. pictipes y de 4 % para R. nasutus. Conclusiones. La capacidad infecciosa (hemolinfática, intestinal y glandular y la transmisión de T. rangeli (SC-58/KP1- fueron mayores y más eficientes en R. pictipes. Estos resultados refuerzan la hipótesis de que estos triatominos actúan como filtros biológicos en la transmisión de T. rangeli.

  10. Estudio de la viabilidad de fabricación de un sistema codo (fundición inoxidable ferrítica, GX 260 Cr27-tubo composite (Incolloy 800 HT+Stal 2465 solidario por fusión

    Directory of Open Access Journals (Sweden)

    Gutiérrez de Solabarría, S.

    1995-10-01

    Full Text Available Flying ashes captured by ciclones in the experimental plant for combustion in pressure fluid bed, in Escatrón Power Plant (Zaragoza, Spain, circulate through the gas cleaning system and are evacuated by means of pneumatic transport. The temperature of these ashes is aprox. 800 °C and the relative pressure is up to 8 negative bars relating the outdoor pressure of the transport pipe. The configuration of the pneumatic transport lines is Incolloy 800 HT quality composite tubes lined with Stal 2465 in straight stretches. Regarding direction changes, ferritic stainless casting, quality GX 260 Cr 27 elbows are used. The aim of this work is to study the possibility of manufacturing a solidary system by means of melting between the ferritic stainless casting elbow and the composite pipe.

    Las cenizas volantes captadas por ciclones en la planta experimental de combustión en lecho fluido a presión, de la central térmica de Escatrón (Zaragoza, circulan por el sistema de depuración de gases y son evacuadas mediante transporte neumático. Estas cenizas se encuentran a una temperatura aproximada de 800 °C y a una presión relativa de hasta 8 bares negativos con respecto a la presión en el exterior de la tubería de transporte. Para configurar las líneas de transporte neumático, se utilizan en los tramos rectos tubos composite de calidad Incolloy 800 HT recubiertos interiormente de material Stal 2465. Para los cambios de dirección, se utilizan codos de fundición inoxidable ferrítica de calidad GX 260 Cr 27. El objetivo del presente trabajo es estudiar la viabilidad de fabricación de un sistema solidario por fusión entre el codo de fundición inoxidable ferrítica y la tubería composite.

  11. Ecological aspects of Rhodnius nasutus Stål, 1859 (Hemiptera: Reduviidae: Triatominae in palms of the Chapada do Araripe in Ceará, Brazil

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    Fernando Braga Stehling Dias

    2008-12-01

    Full Text Available The aim of this work is to present aspects related to the ecology of Rhodnius nasutus Stål, 1859 in palms from Chapada do Araripe in Ceará, Brazil. The following five species of palms were investigated: babaçu (Attalea speciosa, buriti (Mauritia flexuosa, carnaúba (Copernicia prunifera, catolé (Syagrus oleracea and macaúba-barriguda (Acrocomia intumescens. Fifth palms were dissected (10 specimens for each species. The overall infestation index was 86%, with a total of 521 triatomines collected. The Trypanosoma cruzi Chagas, 1909 Index was 16.8% and two insects presented mixed infection with Trypanosoma rangeli Tejera, 1920. A precipitin test showed that R. nasutus from palms of Chapada do Araripe are associated with opossum and bird although other possible bloodmeals were observed. Our results showing a high index of infestation of the palms as well as T. cruzi infection, the association of R. nasutus with the most diverse species of palms and proximity of these palms to houses demonstrate the importance of this area for sylvatic T. cruzi transmission and suggest the need for epidemiological surveillance in the region of the Chapada do Araripe.

  12. Life cycle, feeding and defecation patterns of Rhodnius ecuadoriensis (Lent & León 1958) (Hemiptera: Reduviidae: Triatominae) under laboratory conditions.

    Science.gov (United States)

    Villacís, Anita G; Arcos-Terán, Laura; Grijalva, Mario J

    2008-11-01

    Rhodnius ecuadoriensis is the second most important vector of Chagas Disease (CD) in Ecuador. The objective of this study was to describe (and compare) the life cycle, the feeding and defecation patterns under laboratory conditions of two populations of this specie [from the provinces of Manabí (Coastal region) and Loja (Andean region)]. Egg-to-adult (n = 57) development took an average of 189.9 +/- 20 (Manabí) and 181.3 +/- 6.4 days (Loja). Mortality rates were high among Lojan nymphs. Pre-feeding time (from contact with host to feeding initiation) ranged from 4 min 42 s [nymph I (NI)] to 8 min 30 s (male); feeding time ranged from 14 min 45 s (NI)-28 min 25 s (male) (Manabí) and from 15 min 25 s (NI)-28 min 57 s (nymph V) (Loja). The amount of blood ingested increased significantly with instar and was larger for Manabí specimens (p Ecuador and Northern Peru.

  13. Life cycle, feeding and defecation patterns of Rhodnius ecuadoriensis (Lent & León 1958 (Hemiptera: Reduviidae: Triatominae under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Anita G Villacís

    2008-11-01

    Full Text Available Rhodnius ecuadoriensis is the second most important vector of Chagas Disease (CD in Ecuador. The objective of this study was to describe (and compare the life cycle, the feeding and defecation patterns under laboratory conditions of two populations of this specie [from the provinces of Manabí (Coastal region and Loja (Andean region]. Egg-to-adult (n = 57 development took an average of 189.9 ± 20 (Manabí and 181.3 ± 6.4 days (Loja. Mortality rates were high among Lojan nymphs. Pre-feeding time (from contact with host to feeding initiation ranged from 4 min 42 s [nymph I (NI] to 8 min 30 s (male; feeding time ranged from 14 min 45 s (NI-28 min 25 s (male (Manabí and from 15 min 25 s (NI-28 min 57 s (nymph V (Loja. The amount of blood ingested increased significantly with instar and was larger for Manabí specimens (p < 0.001. Defecation while feeding was observed in Manabí specimens from stage nymph III and in Lojan bugs from stage nymph IV. There was a gradual, age-related increase in the frequency of this behaviour in both populations. Our results suggest that R. ecuadoriensis has the bionomic traits of an efficient vector of Trypanosoma cruzi. Together with previous data on the capacity of this species to infest rural households, these results indicate that control of synanthropic R. ecuadoriensis populations in the coastal and Andean regions may have a significant impact for CD control in Ecuador and Northern Peru.

  14. Domestic Rhodnius ecuadoriensis (Hemiptera, Reduviidae) infestation in Northern Peru: a comparative trial of detection methods during a six-month follow-up.

    Science.gov (United States)

    Cuba Cuba, César Augusto; Vargas, Franklin; Roldan, Judith; Ampuero, Cynthia

    2003-01-01

    Two passive methods in the assessment of intradomiciliary infestation by Rhodnius ecuadoriensis were tested: (i) the Gomes Nu ez sensor box (GN), (ii) sheets of white typing paper and (iii) one active timed manual method. The study was carried out in the Alto Chicama River Valley, Province of Gran Chim , Department of La Libertad. The study design consisted of an initial searching of triatomines inside of the domestic environment by the manual capture active procedure (man/hour) covering all the studied houses. Then, matched pairs of GN boxes and paper sheets were simultaneously installed in the bedrooms of 207 households distributed in 19 localities. A comparative prospective trial of these passive detection devices were monitored at 2, 4 and, finally 6 months follow-up. Parasitological Trypanosoma rangeli and/or T. cruzi infections were investigated in two houses with high level of infestation by R. ecuadoriensis. 16.9% of the 207 households investigated by an initial active manual method were infested with R. ecuadoriensis. The proportion of infested houses fluctuated from 6.2 to 55.5% amongst the 19 localities investigated. T. rangeli natural infection was detected in R. ecuadoriensis specimens collected in two households. Parasite rates in the bugs ranged from 16.6 to 21.7% respectively. The most striking fact was an average rate of salivary gland infection ranging from 7.4 to 8.3%. At the end of the sixth month period, a cumulative incidence of 31.4% of positive GN boxes against 15.9% for paper sheets was recorded. All three methods combined detected domestic infestation in 129 (62.3%) of the 207 houses studied in the 19 localities. The range of houses infested varies from 6.7% to 92.9%. In areas with low bug density infestation rates, the methodology experienced in our studies, seems to be the best choice for investigations on domestic R. ecuadoriensis populations.

  15. Conocimientos y factores de riesgo relacionados con la enfermedad de Chagas en dos comunidades panameñas donde Rhodnius pallescens es el vector principal

    Directory of Open Access Journals (Sweden)

    Lisbeth A. Hurtado

    2014-06-01

    Full Text Available Introducción. La implementación de los programas de vigilancia, prevención y control de la enfermedad de Chagas requiere una aproximación integral. La sostenibilidad de los programas depende de la participación comunitaria amparada en un conocimiento básico del problema. Objetivo. Evaluar los conocimientos de los entrevistados que facilitan o limitan la vigilancia, prevención y control de la enfermedad de Chagas en dos comunidades endémicas de Panamá donde Rhodnius pallescens es el vector principal. Materiales y métodos. Mediante un cuestionario se evaluaron los conocimientos y los factores de riesgo relacionados con la enfermedad de Chagas en 201 personas mayores de 10 años de las comunidades endémicas de Las Pavas y Lagartera Grande, ubicadas en la ribera oeste del Canal de Panamá. Con ayuda de los moradores también se evaluó la presencia de chinches triatominos en 93 viviendas a lo largo de un año. Resultados. De las personas entrevistadas, 69,2 % (139/201 tenía pocos o muy pocos conocimientos sobre la enfermedad de Chagas y 93 % (187/201 estaba expuesto a factores de riesgo moderados o altos. Se capturaron chinches triatominos en 20,4 % (19/93 de las viviendas evaluadas, de los cuales, el 86,8 % (66/76 era R. pallescens. Se encontró asociación significativa entre la presencia de chinches dentro de las viviendas y las viviendas catalogadas como precarias (p<0,01. Conclusión. A pesar de que en estas dos comunidades se han desarrollado programas de educación sanitaria, es necesario reforzar los conocimientos básicos sobre la enfermedad de Chagas antes de establecer medidas de prevención y vigilancia que involucren la participación activa de sus habitantes.

  16. Potencial reprodutivo de Supputius cincticeps (Stal (Heteroptera: Pentatomidae influenciado pelo peso do corpo da fêmea - DOI: 10.4025/actascibiolsci.v25i1.2081 Reproductive potential of the predator Supputius cincticeps (Heteroptera: Pentatomidae affected by female body weight - DOI: 10.4025/actascibiolsci.v25i1.2081

    Directory of Open Access Journals (Sweden)

    Jose Eduardo Serrão

    2003-04-01

    Full Text Available O potencial reprodutivo de fêmeas de Supputius cincticeps (Stal (Heteroptera: Pentatomidae de duas classes de peso foi avaliado. Machos e fêmeas desse predador foram obtidos de ninfas alimentadas com pupas de Tenebrio molitor L. (Coleoptera: Tenebrionidae. Foram analisadas fêmeas com peso inferior a 45 mg (fêmeas leves e superior a 60 mg (fêmeas pesadas. A longevidade e os períodos de pré-oviposição, oviposição e pós-oviposição foram semelhantes entre fêmeas das duas classes de peso, enquanto aquelas mais pesadas apresentaram maior número de posturas, ovos, ovos/postura e ninfas. Períodos entre posturas e de incubação dos ovos foram menores para fêmeas com peso superior a 60mg. Esses resultados são discutidos em relação ao uso de fêmeas mais pesadas de S. cincticeps para aumentar a produção em criação massal desse predadorThe reproductive potential of Supputius cincticeps (Stal (Heteroptera: Pentatomidae females of two weight classes was evaluated with males and females of this predator obtained from nymphs fed on Tenebrio molitor L. (Coleoptera: Tenebrionidae pupae. Females of S. cincticeps weighing less than 45 mg (light females and more than 60 mg (heavy females constituted the treatments. Pre-oviposition, oviposition and post-oviposition periods besides adult longevity were similar between treatments while number of egg masses, eggs, eggs/egg mass and number of nymphs hatched were higher for heavier females. Periods between egg mass laying and egg incubation were shorter for insects of the last treatment. These results are discussed in relation to the use of heavier females of S. cincticeps to improve mass rearing of this predator in laboratory

  17. Índice de defecación y éxito reproductivo de Triatoma maculata (Hemiptera:Reduviidaeen condiciones de laboratorio

    Directory of Open Access Journals (Sweden)

    E Aldana

    2004-12-01

    Full Text Available Se estudió el comportamiento reproductivo y de defecación de Triatoma maculata (Erichson 1848alimentando artificialmente con sangre humana.Los estadios II y III mostraron mayor frecuencia de defecaciones (ID=0.6 n=40,el estadio V no alcanzó la diferenciación sexual, la fertilidad fue 55%(n=865,fecundidad 8 huevos/hembra/semana (n=26,22 días de desarrollo embrionario (n=477,longevidad de hembras 51 días (n=26,el tiempo intermuda aumenta progresivamente desde 35 días en el estadio I hasta 46 días en el estadio IV,el porcentaje de muda varió desde 0%en el estadio V hasta 63%en el estadio III,la mortalidad varió desde 8%en el estadio III hasta 100%en el estadio V (n=40.Los resultados del presente trabajo aportan evidencias que explican la menor capacidad vectorial y la baja densidad de T.maculata en el domicilio humano.Defecation index and reproductive success of Triatoma maculata (Hemiptera: Reduviidae under laboratory conditions.The reproductive and defecating behavior of Triatoma maculata (Erichson 1848was studied on animals from an university culture in Venezuela.This species does not reach the importance of Rhodnius prolixus Stal 1859 as Chagas disease vector in Venezuela.This study addressed the role of defecating frequency,an index of how dangerous the animals are for the human population,and its relationship with why T.maculata is a less important vector than R.prolixus .Human blood was fed to the insects through an artificial feeding device.The 2nd and 3rd instar nymphs defecated more frequently (Id=0.6,n=40,and our Vth instar nymphs did not complete sexual differentiation.Fertility was 55%(n=865and fecundity 8 eggs/female/week (n=26. Egg incubation lasted 22 days (n=477.Female longevity was 51 days (n=26.Intermould time grew progressively from 35 days for 1st to 40 days for 4th instar nymphs (n=40.Mould percentage varied from 0% for Vth to 63%for 3rd instar nymphs.Mortality varied from 8% for 3rd to 100% for Vth instar nymphs

  18. The characterization of new hormonal systems in arthropods with a focus on neuropeptide GPCRs

    DEFF Research Database (Denmark)

    Stafflinger, Elisabeth

    Anopheles gambiae, Aedes aegypti, and Culex pipiens, the silkworm Bombyx mori, T. castaneum, N. vitripennis, and the bug Rhodnius prolixus but not in all the other sequenced insect genomes. Bioassays showed that only ACP can activate the ACPR, but not AKH or corazonin, showing that this system...

  19. Estrutura de populações de Rhodnius neglectus Lent e Psammolestes tertius Lent & Jurberg (Hemiptera, Reduviidae em ninhos de pássaros (Furnariidae presentes na palmeira Mauritia flexuosa no Distrito Federal, Brasil Population structure of Rhodnius neglectus Lent and Psammolestes tertius Lent & Jurberg (Hemiptera, Reduviidae in bird nests (Furnariidae on Mauritia flexuosa palm trees in Federal District of Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Gurgel-Gonçalves

    2007-03-01

    Full Text Available Rhodnius neglectus Lent, 1954 {Rn}e Psammolestes tertius Lent & Jurberg, 1965 {Pt} são triatomíneos que ocorrem em ninhos de aves, principalmente da família Furnariidae. O ciclo biológico dessas espécies é conhecido em condições de laboratório, sendo poucos estudos em ecótopos silvestres. Para analisar a infestação e estrutura de populações de Rn e Pt em ninhos de aves presentes na palmeira Mauritia flexuosa Linnaeus, em duas estações climáticas do Brasil Central, foram amostradas 41 palmeiras com evidências de nidificação de Phacellodomus ruber Vieillot, 1817 (22 na estação chuvosa e 19 na estação seca em quatro áreas do Distrito Federal. Os insetos foram capturados usando-se coleta manual na copa da palmeira, identificados morfologicamente, separados por sexo e estádio ninfal. Fezes e glândulas salivares de Rn foram examinadas para verificar infecção por Trypanosoma cruzi Chagas, 1909 e/ou T. rangeli Tejera, 1920. Trinta e cinco palmeiras com ninhos de P. ruber estavam infestadas por Rn (85% e 22 por Pt (53%. 442 indivíduos foram coletados na estação seca (200 Rn e 242 Pt e 267 na estação chuvosa (136 Rn e 131 Pt. O único fator relacionado significativamente com a densidade de triatomíneos nas palmeiras foi a área. A estrutura etária das populações mostrou: a maior abundância de adultos nas populações de Pt, b maior abundância de machos em ambas as espécies e c presença de fêmeas ovipondo em ambas as estações. Nenhum dos 177 triatomíneos examinados estava infectado por T. cruzi ou T. rangeli. A estrutura etária das populações de Rn e Pt não diferiu significativamente entre as estações amostradas, indicando ausência de marcada sazonalidade para essas espécies.Rhodnius neglectus Lent, 1954 {Rn}and Psammolestes tertius Lent & Jurberg, 1965 {Pt} are triatomines that occur in bird nests, mainly furnarid nests. Their biological cycles are known in laboratory conditions and few studies were

  20. "Mir stal grubeje, zhesttshe, tsinitshneje" / Jevgeni Levik

    Index Scriptorium Estoniae

    Levik, Jevgeni

    2005-01-01

    Mängufilmid "Rünnak 13. jaoskonnale" ("Assault on Precinct 13"), režissöör Jean-Francois Richet, Ameerika Ühendriigid-Prantsusmaa 2005 ja "Peitusemäng" ("Hide and Seek"), režissöör John Polson, Ameerika Ühendriigid 2005

  1. A novel association between Rhodnius neglectus and the Livistona australis palm tree in an urban center foreshadowing the risk of Chagas disease transmission by vectorial invasions in Monte Alto City, São Paulo, Brazil.

    Science.gov (United States)

    Carvalho, Danila B; Almeida, Carlos E; Rocha, Cláudia S; Gardim, Sueli; Mendonça, Vagner J; Ribeiro, Aline R; Alves, Zulimar C P V T; Ruellas, Kellem T; Vedoveli, Alan; da Rosa, João A

    2014-02-01

    After several public notifications of domiciliary invasions, palm trees were investigated in downtown Monte Alto City, São Paulo State, Brazil, in proximity to the city hall building, the main church, condominiums and marketing establishments. One hundred seventy four palm trees of 10 species were investigated, in which 72 specimens of Rhodnius neglectus, a potential Chagas disease vector, were captured via manual methods. All insects were collected from dead leaves, organic debris and bird nests in the only three Livistona australis palm trees in the central park square. This was the first record of R. neglectus colonizing this palm species. Although no Trypanosoma cruzi was found by abdominal compression followed by light microscopy, the poor nutritional status of the bugs hampered the examination of gut contents for parasite detection. Furthermore, the central crowns of the trees, which shelter bats (Chiroptera: Mammalia), could not be carefully searched for insects due to difficult access. This new finding highlights the sudden alteration in insect behavior, probably as a result of man's interference. This report aims to warn those involved in the health system about this new threat, justifying detailed research of the area to evaluate the magnitude of this emerging public health issue. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Hematophagous insects as vectors for frog trypanosomes.

    Science.gov (United States)

    Ramos, B; Urdaneta-Morales, S

    1977-12-01

    Experimental infections of three hematophagous arthropods (Rhodnius prolixus, Aedes aegypti, and Culex pipiens) with a trypanosome of the Trypanosoma rotatorium complex found in the frogs Hyla crepitans and Leptodactylus insularum revealed that A. aegypti is a good host for the flagellate; the course of development in the intestinal tract of the mosquito is described from 15 minutes to 168 hours. C. pipiens showed only low intestinal infections and R. prolixus did not permit development of the parasite. It is postulated that, in addition to the transmission of T. rotatorium by leeches, batrachophilic mosquitoes may transmit the parasite to frogs of more terrestrial habits by being ingested by these anurans.

  3. Epidemiologia da doença de Chagas na zona rural do Município de Teresina-Piauí, Brasil

    Directory of Open Access Journals (Sweden)

    Dalva Neves da Costa Bento

    1992-03-01

    Full Text Available Na área rural do município de Teresina-Piauí, foram capturados 129 triatomíneos distribuídos em (a ecótopos artificiais: habitações (1 Triatoma brasiliensis, 1 Panstrongylus geniculatus, 1 Rhodnius pictipes e 1 Rhodnius prolixusj e galpão abandonado (7 Rhodnius nasutusj e (b ecótopos naturais: Orbignya martiana (41 Rhodnius neglectus, 33 Rhodnius prolixus e 41 Rhodnius nasutus, e Copernicia cerifera (3 Rhodnius neglectus,. Cerca de 22,6% dos triatomíneos capturados estavam infectados por flagelados, sendo 30% no ambiente artificial e 21,9% no ambiente natural. Dos 28 mamíferos capturados e examinados, 7 Didelphis aibiventris, 2 Rattus rattus e 1 Tamandua tetradacty la apresentavam-se positivos para flagelados. Os flagelados encontrados nos triatomíneos e nos mamíferos eram semelhantes ao Trypanosoma cruzi. Das 123 reações sorológicas, por imunojluorescência indireta, realizadas na população, duas (1,6% foram reativas.

  4. Otrok, který se stal králem

    Czech Academy of Sciences Publication Activity Database

    Květina, Petr

    2017-01-01

    Roč. 19, prosinec (2017), s. 52-58 ISSN 1213-1628 Institutional support: RVO:67985912 Keywords : slavery * power strategy * style of material culture Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology

  5. Gasvormige stikstofverliezen uit stal en opslag: verschillen in berekeningsmethoden

    NARCIS (Netherlands)

    Hoogeveen, M.W.; Luesink, H.H.; Bruggen, van C.

    2006-01-01

    Ingevolge de Wet Milieubeheer brengt het Milieu- en Natuurplanbureau van het RIVM (MNP-RIVM) jaarlijks een Milieubalans uit. Berekeningen met het Mest- en Ammoniakmodel van ammoniakemissie en andere gasvormige stikstofverliezen liggen ten grondslag aan de cijfers in de publicatie. De geconstateerde

  6. Lethal mutation of internal irradiation brown planthopper (Nilaparvita lugens Stal)

    International Nuclear Information System (INIS)

    Wahid, R.A.

    1988-01-01

    The moulting IVth of BPH nympha were irradiated internally with radiophosphorous 32-P 1 uCi/ml, 10 uCi/ml, 50 uCi/ml, 100 uCi/ml, and 500 uCi/ml concentrations respectivelly. An observation was carried out to determines heredity of hopper sterilities from the mating groups of R male x N female, R male x R female, and N male x R female. The 32-P concentration below of 50 uCi/ml seemed to be the substerile dose, however, the dominant lethal mutation has been visually shown by R male x R female F1 mating group. The hereditary lines of F1, F2, F3, and F4 of the hopper sterilities wich were indicated by the nympha hatch ability have some significant correlations (r1= -0.77, r2= -0.92, r3= -0.93 and r4= -0.85). Thus, the resesif lethal mutations visually showed by F3 and F4 from all of the 100 uCi/ml and 50 uCi/ml treated groups. (author). 10 refs, 2 figs, 2 tabs

  7. Countercurrent heat exchange and thermoregulation during blood-feeding in kissing bugs.

    Science.gov (United States)

    Lahondère, Chloé; Insausti, Teresita C; Paim, Rafaela Mm; Luan, Xiaojie; Belev, George; Pereira, Marcos H; Ianowski, Juan P; Lazzari, Claudio R

    2017-11-21

    Blood-sucking insects experience thermal stress at each feeding event on endothermic vertebrates. We used thermography to examine how kissing-bugs Rhodnius prolixus actively protect themselves from overheating. During feeding, these bugs sequester and dissipate the excess heat in their heads while maintaining an abdominal temperature close to ambient. We employed a functional-morphological approach, combining histology, µCT and X-ray-synchrotron imaging to shed light on the way these insects manage the flow of heat across their bodies. The close alignment of the circulatory and ingestion systems, as well as other morphological characteristics, support the existence of a countercurrent heat exchanger in the head of R. prolixus , which decreases the temperature of the ingested blood before it reaches the abdomen. This kind of system has never been described before in the head of an insect. For the first time, we show that countercurrent heat exchange is associated to thermoregulation during blood-feeding.

  8. Biology, diversity and strategies for the monitoring and control of triatomines--Chagas disease vectors.

    Science.gov (United States)

    Costa, Jane; Lorenzo, Marcelo

    2009-07-01

    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 triatomines as a basis for new strategies for monitoring and controlling the vectorial transmission are discussed here. The importance of ongoing long-term monitoring activities for house infestations by T. infestans, Triatoma brasiliensis, Panstrongylus megistus, Triatoma rubrovaria and R. prolixus is also stressed, as well as understanding the invasion by sylvatic species. Moreover, the insecticide resistance is analysed. Strong efforts to sustain and improve surveillance procedures are crucial, especially when the vectorial transmission is considered interrupted in many endemic areas.

  9. Dicty_cDB: Contig-U04780-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available Ancylostoma ceylanicum L3 Ancylostoma ... 44 6.7 1 ( GE813038 ) EST_scau_evk_974138 scauevk mixed_tissue Sebaste...s... 44 6.7 1 ( GE802768 ) EST_scau_evk_897256 scauevk mixed_tissue Sebastes... 44 6.7 1 ( GE802767 ) ES...T_scau_evk_896872 scauevk mixed_tissue Sebastes... 44 6.7 1 ( GE800881 ) EST_scau..._evk_891797 scauevk mixed_tissue Sebastes... 44 6.7 1 ( FD779328 ) NADG-aaa04h04.g1 Rhodnius_prolixus_EST_NA

  10. A mathematical model of Chagas disease transmission

    Science.gov (United States)

    Hidayat, Dayat; Nugraha, Edwin Setiawan; Nuraini, Nuning

    2018-03-01

    Chagas disease is a parasitic infection caused by protozoan Trypanosoma cruzi which is transmitted to human by insects of the subfamily Triatominae, including Rhodnius prolixus. This disease is a major problem in several countries of Latin America. A mathematical model of Chagas disease with separate vector reservoir and a neighboring human resident is constructed. The basic reproductive ratio is obtained and stability analysis of the equilibria is shown. We also performed sensitivity populations dynamics of infected humans and infected insects based on migration rate, carrying capacity, and infection rate parameters. Our findings showed that the dynamics of the infected human and insect is mostly affected by carrying capacity insect in the settlement.

  11. Nitric oxide heme interactions in nitrophorin from Cimex lectularius

    Energy Technology Data Exchange (ETDEWEB)

    Christmann, R.; Auerbach, H., E-mail: auerbach@physik.uni-kl.de [University of Kaiserslautern, Department of Physics (Germany); Berry, R. E.; Walker, F. A. [The University of Arizona, Department of Chemistry and Biochemistry (United States); Schünemann, V. [University of Kaiserslautern, Department of Physics (Germany)

    2016-12-15

    The nitrophorin from the bedbug Cimex lectularius (cNP) is a nitric oxide (NO) carrying protein. Like the nitrophorins (rNPs) from the kissing bug Rhodnius prolixus, cNP forms a stable heme Fe(III)-NO complex, where the NO can be stored reversibly for a long period of time. In both cases, the NPs are found in the salivary glands of blood-sucking bugs. The insects use the nitrophorins to transport the NO to the victim’s tissues, resulting in vasodilation and reduced blood coagulation. However, the structure of cNP is significantly different to those of the rNPs from Rhodnius prolixus. Furthermore, the cNP can bind a second NO molecule to the proximal heme cysteine when present at higher concentrations. High field Mössbauer spectroscopy on {sup 57}Fe enriched cNP complexed with NO shows reduction of the heme iron and formation of a ferrous nitric oxide (Fe(II)-NO) complex. Density functional theory calculations reproduce the experimental Mössbauer parameters and confirm this observation.

  12. Feeding sources and trypanosome infection index of Rhodnius pallescens in a Chagas disease endemic area of Amador County, Panama Fontes de alimentação de R. pallescens e índice de infecção por Trypanosoma em área endêmica da doença de Chagas em Amador, região central do Panamá

    Directory of Open Access Journals (Sweden)

    Vanessa Pineda

    2008-04-01

    Full Text Available The sylvatic triatomine Rhodnius pallescens is considered to be the most important and widespread vector of Trypanosoma cruzi and Trypanosoma rangeli in Panama. However, its behavior and biological characteristics have only been partially investigated. Thus, to achieve sustainable and efficient control over Chagas disease in Panama, a better understanding of the ecology and biology of R. pallescens is essential. In this study we evaluated R. pallescens host feeding sources using a dot-blot assay, and the trypanosome infection index by PCR analysis in a Chagas disease endemic area of central Panama. It was found that in peridomestic palm trees, 20.3% of the examined bugs had fed on opossums (Didelphis marsupialis. However, we observed an increased anthropophagy (25.4% for those bugs collected inside houses. Considering the domestic and peridomestic habitats as a whole, the proportion of collected R. pallescens infected with trypanosomes was 87.4%. In the two habitats the predominant infection was with T. cruzi (80-90%. Between 47-51% of the analyzed triatomines were infected with T. rangeli. Mixed infections (40-51% were also detected. These findings provide a better basis for the implementation of a rational control and surveillance program for Chagas disease in regions where R. pallescens is endemic.O triatomíneo silvestre Rhodnius pallescens é considerado o mais importante vetor do Trypanosoma cruzi e Trypanosoma rangeli no Panamá. Entretanto, seu comportamento e características biológicas são pouco estudados. Para controlar a doença de Chagas no Panamá é necessário melhorar a compreensão dos aspectos eco-biológicos do R. pallescens. Neste estudo, investigaram-se as fontes de alimentação de R. pallescens usando dot-blot e o índice de infecção por Trypanosoma por metodologia molecular, em área endêmica da doença de Chagas na região central do Panamá. Foi observado que 20,3% dos barbeiros coletados em palmeiras peridom

  13. GENETICS OF BROWN PLANTHOPPER (NILAPARVATA LUGENS STAL.) RESISTANCE IN ELITE DONORS OF RICE (ORYZA SATIVA L.)

    OpenAIRE

    B BALAKRISHNA; P V SATAYANARAYANA

    2013-01-01

    The inheritance of resistance to the brown planthopper (BPH) in four BPH resistant donors of rice i. e., Sinna Sivappu, Sudu Hondarawala, PTB 33 and BM 71 was studied both in field and greenhouse conditions. The F2 population of crosses involving donors Sinna Sivappu, Sudu Hondarawala and PTB 33 fit into the ratio of 13:3 indicating the resistance to BPH was controlled by two genes i. e., one dominant and one recessive gene segregating independent to each other. The F2 populat...

  14. Use of P-32 for determining varietal resistance of rice to brown planthopper (Nilaparvata lugens stal)

    Energy Technology Data Exchange (ETDEWEB)

    Kuswadi, A.N. (National Atomic Energy Agency, Jakarta (Indonesia). Pasar Djumat Research Centre)

    1981-07-01

    The resistance was assessed based on the feeding activities of the insect on 15-day old seedling of six test varieties namely TN 1, Asahan, Brantas, Citarum, Serayu and Mudgo. A level of 175 ..mu..Ci per seedling appeared to give sufficiently high absorption of radiophosphorus by the brown planthoppers. The level of radioactivity in the brown planthopper fed for 24 hours on labelled rice plants appeared to be correlated with the susceptibility of the rice plant to brown planthopper. The radioactivity in the honeydew of those hoppers was less correlated with the rice susceptibility. The promising resistance screening method using P-32 tracer is thus more reliable when the radioactivity is detected in the insect rather than in the honeydew.

  15. [Use of new tools for controlling triatomines in different entomologic situations in the American continent].

    Science.gov (United States)

    Oliveira Filho, A M

    1997-01-01

    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-treatment results for the three countries show an efficient control when insecticide paints were used indoors and in the peridomicilium, keeping reinfestation near zero. The final results presented for Chile two years post-treatment confirmed the superiority of the slow-release "paints". Sensor boxes were less effective than man/hour captures in the detection of infested houses.

  16. Genetic basis of triatomine behavior: lessons from available insect genomes

    Directory of Open Access Journals (Sweden)

    Jose Manuel Latorre-Estivalis

    2013-01-01

    Full Text Available Triatomines have been important model organisms for behavioural research. Diverse reports about triatomine host search, pheromone communication in the sexual, shelter and alarm contexts, daily cycles of activity, refuge choice and behavioural plasticity have been published in the last two decades. In recent times, a variety of molecular genetics techniques has allowed researchers to investigate elaborate and complex questions about the genetic bases of the physiology of insects. This, together with the current characterisation of the genome sequence of Rhodnius prolixus allows the resurgence of this excellent insect physiology model in the omics era. In the present revision, we suggest that studying the molecular basis of behaviour and sensory ecology in triatomines will promote a deeper understanding of fundamental aspects of insect and, particularly, vector biology. This will allow uncovering unknown features of essential insect physiology questions for a hemimetabolous model organism, promoting more robust comparative studies of insect sensory function and cognition.

  17. Seroprevalence of human Trypanosoma cruzi infection in diferent geografic zones of Chiapas, Mexico.

    Science.gov (United States)

    Mazariego-Arana, M A; Monteón, V M; Ballinas-Verdugo, M A; Hernández-Becerril, N; Alejandre-Aguilar, R; Reyes, P A

    2001-01-01

    A serologic survey was carried out in four different geographic zones of Chiapas, Mexico. A total of 1,333 samples were collected from residents of thirteen communities located on the Coast, Central Mountain, Lacandon Forest and a zone called Mesochiapas. One hundred and fifty one seropositive individuals (11.3%) were identified. Human Trypanosoma cruzi infection was influenced by geography. In the Lacandon Forest and Central Mountains there was a higher seroprevalence 32.1 and 13.8% respectively, than on the coast (1.2%). In Mesochiapas there were no seropositive individuals among the 137 persons tested. An active transmission is probably continuing because seropositive cases (13.8%) were detected in children under 10 years of age. The vector recognized on the Coast was Triatoma dimidiata while in the Lacandon Forest it was Rhodnius prolixus.

  18. Lysophosphatidylcholine: A Novel Modulator of Trypanosoma cruzi Transmission

    Science.gov (United States)

    Silva-Neto, Mário A. C.; Carneiro, Alan B.; Silva-Cardoso, Livia; Atella, Georgia C.

    2012-01-01

    Lysophosphatidylcholine is a bioactive lipid that regulates a large number of cellular processes and is especially present during the deposition and infiltration of inflammatory cells and deposition of atheromatous plaque. Such molecule is also present in saliva and feces of the hematophagous organism Rhodnius prolixus, a triatominae bug vector of Chagas disease. We have recently demonstrated that LPC is a modulator of Trypanosoma cruzi transmission. It acts as a powerful chemoattractant for inflammatory cells at the site of the insect bite, which will provide a concentrated population of cells available for parasite infection. Also, LPC increases macrophage intracellular calcium concentrations that ultimately enhance parasite invasion. Finally, LPC inhibits NO production by macrophages stimulated by live T. cruzi, and thus interferes with the immune system of the vertebrate host. In the present paper, we discuss the main signaling mechanisms that are likely used by such molecule and their eventual use as targets to block parasite transmission and the pathogenesis of Chagas disease. PMID:22132309

  19. The isolation and identification of Trypanosoma cruzi from raccoons in Maryland

    Science.gov (United States)

    Walton, B.C.; Bauman, P.M.; Diamond, L.S.; Herman, C.M.

    1958-01-01

    Five raccoons trapped at Patuxent Research Refuge, Laurel, Maryland, were found to have trypanosomes in the blood which were morphologically indistinguishable from Trypanosoma cruzi on stained smears. The organism grew well in culture. It developed and reproduced in Triatoma protracta, T. infestans, T. phyllosoma, and Rhodnius prolixus. Experimental infections were produced in raccoons, opossums, mice, rats, and monkeys by inoculation of blood, culture, and triatome forms. Typical leishmaniform bodies were found in tissue sections of cardiac muscle fibers from naturally and experimentally infected animals. Cross agglutinations carried out with Iiving cultural forms and rabbit antisera demonstrated a close antigenic relationship between the raccoon trypanosome and T. cruzi (Brazil strain). On the basis of (1) morphology, (2) presence of leishmaniform tissue stages, (3) development in triatomes, (4) infectivity to a variety of mammals, (5) culture characteristics, and (6) cross reactions in serological tests, this parasite is considered conspecific with Trypanosoma cruzi (Chagas, 1909), the causative agent of American human trypanosomiasis.

  20. Modeling the effects of palm-house proximity on the theoretical risk of Chagas disease transmission in a rural locality of the Orinoco basin, Colombia

    Directory of Open Access Journals (Sweden)

    Diana Erazo

    2016-11-01

    Full Text Available Abstract Background Chagas disease is a major public health concern in Latin America and it is transmitted by insects of the subfamily Triatominae, including Rhodnius spp. Since palm trees are ubiquitous in Colombia and a habitat for Rhodnius spp., the presence of palms near villages could increase contact rates between vectors and humans. Therefore, knowing whether a relationship exists between the proximity of palms to villages and the abundance and distribution of vectors therein, may be critical for Chagas disease prevention programs. Adapting a mathematical model for R. prolixus population dynamics in a small village, we model the implications of changing distances between palms and dwellings, to the risk of Chagas disease infection. Methods We implemented a mathematical model that reflects R. prolixus population dynamics in a small village located in the department of Casanare (Colombia to study the role of palm-house proximity. We varied the distance between palms and houses by monitoring the network global efficiency metric. We constructed 1,000 hypothetical villages varying distances and each one was run 100 times. Results According to the model, as palm-house proximity increases, houses were more likely to be visited by triatomine bugs. The number of bugs per unit time increased progressively in a non-linear fashion with high variability. We stress the importance of village configuration on the model output. Conclusions From a theoretical perspective, palm-house proximity may have a positive effect on the incidence of Chagas disease. The model predicts a 1% increase in new human cases per year when houses and palms are brought closer by 75%.

  1. A multidisciplinary approach to the study of the fluminense vegetation

    Directory of Open Access Journals (Sweden)

    ALPHONSE KELECOM

    2002-03-01

    Full Text Available The fluminense vegetation, more specifically the flora from the Jurubatiba restinga has been investigated by a multidisciplinary team of botanists, chemist, radiobiologist, insect physiologists and geneticist. Vouchers of 564 specimens have been collected, identified, organized in an herbarium, and a database is being build up containing, in addition to classical botanical data, chemical data and information on the potential economic use either for landscape gardening, alternative foods or as medicinal plants. Phytochemical studies of the Guttiferae, Clusia hilariana, yielded oleanolic acid and nemorosone. Their biological activities against the haematophagous insect Rhodnius prolixus vector of Chagas disease have been investigated. Finally, it has been observed that aquatic plants possessed high levels of the natural radionuclide polonium-210, which seems to be originated mainly from soil rather than from atmospheric supply.A vegetação fluminense, em particular aquela proveniente da Restinga de Jurubatiba, foi investigada por um grupo multidisciplinar de botânicos, químico, radiobiólogo, fisiologistas de insetos e geneticista. Amostras de 564 espécimes foram coletadas, identificadas, organizadas em herbário e um banco de dados está sendo elaborado contendo, além das clássicas informações botânicas, dados químicos e indicações quanto ao uso econômico potencial destas plantas, em paisagismo, como alimentos alternativos ou como plantas medicinais. Estudos fitoquímicos da Guttiferae, Clusia hilariana, forneceram ácido oleanólico e nemorosona. Estes metabólitos foram ensaiados no barbeiro Rhodnius prolixus, vetor da doença de Chagas. Por fim, observou-se que plantas aquáticas apresentaram teores muito altos do radionuclídeo natural, polônio-210, fato este que parece estar relacionado mais com as condições de solo do que com um aporte atmosférico.

  2. Seroprevalence of human Trypanosoma cruzi infection in diferent geografic zones of Chiapas, Mexico Soroprevalência da infecção humana pelo Trypanosoma cruzi em diferentes regiões de Chiapas, México

    Directory of Open Access Journals (Sweden)

    Miguel Angel Mazariego-Arana

    2001-10-01

    Full Text Available A serologic survey was carried out in four different geographic zones of Chiapas, Mexico. A total of 1,333 samples were collected from residents of thirteen communities located on the Coast, Central Mountain, Lacandon Forest and a zone called Mesochiapas. One hundred and fifty one seropositive individuals (11.3% were identified. Human Trypanosoma cruzi infection was influenced by geography. In the Lacandon Forest and Central Mountains there was a higher seroprevalence 32.1 and 13.8% respectively, than on the coast (1.2%. In Mesochiapas there were no seropositive individuals among the 137 persons tested. An active transmission is probably continuing because seropositive cases (13.8% were detected in children under 10 years of age. The vector recognized on the Coast was Triatoma dimidiata while in the Lacandon Forest it was Rhodnius prolixus.Foi feito um estudo sorológico em quatro zonas geográficas do estado de Chiapas México. Foram colhidas 1333 amostras dos habitantes das 13 comunidades situadas na costa, na região central montanhosa, na floresta lacandona e na região chamada mesochiapas. Cento cinqüenta e uma pessoas (11,3% foram identificadas como soropositivas. A infecção pelo Trypanosoma cruzi teve a influência da geografia local. Na floresta lacandona nas montanhas centrais, foi encontrada uma prevalência de 32,1 e 13,8% respectivamente, mais que na costa 1,2%. Na zona de mesochiapas não foi encontrada nenhuma pessoa com sorologia positiva entre 137 estudadas. Como encontramos sorologia positiva em crianças menores de 10 anos, pensamos que exista uma transmissão ativa contínua. Na costa foi reconhecido o vetor Triatoma dimidiata e na floresta Lacandona o Rhodnius prolixus.

  3. Triatominos (Reduviidae: Triatominae en un foco de enfermedad de Chagas en Talaigua Nuevo (Bolívar, Colombia.

    Directory of Open Access Journals (Sweden)

    Luis Alberto Corté

    2005-12-01

    Full Text Available Introducción. Se describen las características e importancia epidemiológica de los triatominos presentes en un foco de enfermedad de Chagas en el municipio de Talaigua Nuevo, departamento de Bolívar. Objetivo. Determinar y correlacionar características ecológicas de los triatominos presentes en un foco de Chagas en el municipio de Talaigua Nuevo, Bolívar. Materiales y métodos. La captura de los triatominos se realizó en 300 domicilios del casco urbano en los que se revisaron el intra y peridomicilio, así como ambientes extradomésticos (palmas de vino y cúmulos de madera y leña. Resultados. Se capturaron 103 triatominos pertenecientes a cuatro especies: Triatoma maculata, Eratyrus cuspidatus, Panstrongylus geniculatus y Rhodnius prolixus. T. maculata, fue la especie predominante (92,3%. El 93% de los triatominos fueron capturados en ambientes intradomiciliarios. Conclusión. Se reporta por primera vez en Bolívar la captura de individuos de T. maculata infectados naturalmente con Trypanosoma sp. Se amplía la distribución geográfica de P. geniculatus y R. prolixus. El análisis de correspondencias múltiples no encontró ninguna relación significativa entre las características físicas de las viviendas y la presencia de triatominos dentro de ellas.

  4. Structure and ligand-binding properties of the biogenic amine-binding protein from the saliva of a blood-feeding insect vector of Trypanosoma cruzi

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xueqing; Chang, Bianca W. [NIH/NIAID, 12735 Twinbrook Parkway, Rockville, MD 20852 (United States); Mans, Ben J. [NIH/NIAID, 12735 Twinbrook Parkway, Rockville, MD 20852 (United States); Agricultural Research Council, Onderstepoort 0110 (South Africa); Ribeiro, Jose M. C.; Andersen, John F., E-mail: jandersen@niaid.nih.gov [NIH/NIAID, 12735 Twinbrook Parkway, Rockville, MD 20852 (United States)

    2013-01-01

    Biogenic amine-binding proteins mediate the anti-inflammatory and antihemostatic activities of blood-feeding insect saliva. The structure of the amine-binding protein from R. prolixus reveals the interaction of biogenic amine ligands with the protein. Proteins that bind small-molecule mediators of inflammation and hemostasis are essential for blood-feeding by arthropod vectors of infectious disease. In ticks and triatomine insects, the lipocalin protein family is greatly expanded and members have been shown to bind biogenic amines, eicosanoids and ADP. These compounds are potent mediators of platelet activation, inflammation and vascular tone. In this paper, the structure of the amine-binding protein (ABP) from Rhodnius prolixus, a vector of the trypanosome that causes Chagas disease, is described. ABP binds the biogenic amines serotonin and norepinephrine with high affinity. A complex with tryptamine shows the presence of a binding site for a single ligand molecule in the central cavity of the β-barrel structure. The cavity contains significant additional volume, suggesting that this protein may have evolved from the related nitrophorin proteins, which bind a much larger heme ligand in the central cavity.

  5. Structure and ligand-binding properties of the biogenic amine-binding protein from the saliva of a blood-feeding insect vector of Trypanosoma cruzi

    International Nuclear Information System (INIS)

    Xu, Xueqing; Chang, Bianca W.; Mans, Ben J.; Ribeiro, Jose M. C.; Andersen, John F.

    2013-01-01

    Biogenic amine-binding proteins mediate the anti-inflammatory and antihemostatic activities of blood-feeding insect saliva. The structure of the amine-binding protein from R. prolixus reveals the interaction of biogenic amine ligands with the protein. Proteins that bind small-molecule mediators of inflammation and hemostasis are essential for blood-feeding by arthropod vectors of infectious disease. In ticks and triatomine insects, the lipocalin protein family is greatly expanded and members have been shown to bind biogenic amines, eicosanoids and ADP. These compounds are potent mediators of platelet activation, inflammation and vascular tone. In this paper, the structure of the amine-binding protein (ABP) from Rhodnius prolixus, a vector of the trypanosome that causes Chagas disease, is described. ABP binds the biogenic amines serotonin and norepinephrine with high affinity. A complex with tryptamine shows the presence of a binding site for a single ligand molecule in the central cavity of the β-barrel structure. The cavity contains significant additional volume, suggesting that this protein may have evolved from the related nitrophorin proteins, which bind a much larger heme ligand in the central cavity

  6. [Entomological study of Trypanosoma cruzi vectors in the rural communities of Sucre state, Venezuela].

    Science.gov (United States)

    García-Jordán, Noris; Berrizbeitia, Mariolga; Concepción, Juan Luis; Aldana, Elis; Cáceres, Ana; Quiñones, Wilfredo

    2015-01-01

    The ecological niche of Reduvidae vectors has been modified due to environmental changes and human encroachment into the rural areas. This study evaluates the current entomological indices of triatomines responsible for Trypanosoma cruzi infection in Sucre State, Venezuela. A cross-sectional and prospective study was conducted in 95 towns and 577 dwellings in the 15 municipalities of the state of Sucre, Venezuela, from August to November, 2008. Triatomine bugs were identified on the basis of morphological characteristics, and their feces examined for T. cruzi infection through direct microscopy. Positive slides were stained with Giemsa and parasites were identified by morphologic characterization. The entomological indices expressing the highest values were dispersion (16.67%) and household colonization (33.33%). The triatomine species captured were: Rhodnius prolixus , Rhodnius main intradomiciliary vector. Despite the low index of vector infection (1.72%), the existence of species with domiciliary and peridomiciliary reproductive success ensures the persistence of the epidemiological chain both for the disease and the parasite.

  7. 2-DE-based proteomic investigation of the saliva of the Amazonian triatomine vectors of Chagas disease: Rhodnius brethesi and Rhodnius robustus

    DEFF Research Database (Denmark)

    Costa, Camila M; Sousa, Marcelo V; Ricart, Carlos André O

    2011-01-01

    The triatomine bugs are obligatory haematophagous organisms that act as vectors of Chagas disease by transmitting the protozoan Trypanosoma cruzi. Their feeding success is strongly related to salivary proteins that allow these insects to access blood by counteracting host haemostatic mechanisms...

  8. Estudos sobre a resistência ao jejum e aspectos nutricionais de Triatoma lecticularia (Stal, 1859 (Hemiptera, Reduviidae, Triatominae Studies on the resistance to fasting and nutritional aspects of Triatoma lecticularia (Stal, 1859 (Hemiptera, Reduviidae, Triatominae

    Directory of Open Access Journals (Sweden)

    José Jurberg

    1989-09-01

    Full Text Available Foi feito um estudo sobre a resistência ao jejum em todas as fases evolutivas e pesagens em diferentes situações nutricionais de Triatoma lecticularia (alimentado; não alimentado; na morte após o jejum com temperatura e umidade registradas. Observou-se que os períodos de resistência das fases ninfais apresentaram médias (dias crescentes: 1º: 45,84; 2º: 61; 3º: 88,74; 4º: 123,47; 5º 162,30. Na fase adulta as médias foram aproximadas à do 3º estádio (para os machos 88,94 e para as fêmeas 83,66. O procedimento de pesagens permitiu registrar a quantidade de sangue ingerido, a perda de peso durante o jejum e o respectivo percentual em relação ao peso inicial. Esta espécie tem assinalada sua distribuição geográfica na região Neártica, onde tem sido encontrda infectada com Trypanosoma cruzi associada a Neotoma micropus Baird e Spermophilus variagatus (Erxeleben.The resistance to fasting of Triatoma lecticularia was studied in all phases of the life cycle and the insect weighed in different nutritional situations (fed, not fed, death after starvation. The temperature and humidity level were also recorded. The nymphal phases showed increasing resistance to fasting as demonstrated by the following averages (days 1st 45.84; 2nd 61; 3rd 88.74; 4th 123.44; 5th 162.30. Upon the adult phase, the averages were similar to those of the 3rd stage for the male insects 88.94 and for females 83.66. The weighing technique allowed for the measeurement of the quantity of blood ingested, the weight loss during the fast and the percentage weight lost as related to the initial weight. The species is found in the Neartic region where it has been found infected with Trypanosoma cruzi and is associated with the terrestial rodents Neotoma micropus Baird and Spermophilus variagatus (Erxelebem.

  9. Chřástal polní - a jeho tajemný hlas našich luk

    Czech Academy of Sciences Publication Activity Database

    Brlík, V.; Koleček, Jaroslav

    2014-01-01

    Roč. 2014, č. 3 (2014), s. 14-15 ISSN 1803-0092 R&D Projects: GA MŠk EE2.3.35.0026 Institutional support: RVO:68081766 Keywords : agri-environmental schemes * conservation management * intensification * succession Subject RIV: EG - Zoology

  10. Effect of extracts of plants with insecticidal activity on the control of Microtheca ochroloma Stal (Col: Chrysomelidae in the laboratory

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    Cíntia Grendene Lima

    2008-03-01

    Full Text Available Extracts of plants with insecticidal activity were tested on the control of Microtheca ochroloma (Col.: Chrysomelidae, an important insect-pest of Brassicaceae, in the larval and adult phases. Two 3-day-old larvae, kept under laboratory conditions (25ºC temperature, 70% relative humidity and 14 hours of photophase, were placed in a glass tube with a leaf of Chinese cabbage (Brassica chinensis previously treated with aqueous extracts (10% p/v of chinaberry leaf (Melia azedarach, chinaberry branch, and tobacco powder (Nicotiana tabacum. The same procedure was repeated in two assays with adult insects. In the first assay, all the previously-mentioned extracts were used, in addition to DalNeem (commercial product of Azadirachta indica. In the second, the insects were exposed to extracts of tabasco pepper fruits (Capsicum frutescens, Surinam cherry (Eugenia unifl ora, jambolan (Syzygium cuminii and eucalyptus leaves (Eucalyptus sp.. All the tests consisted of 10 insects per treatment, with five repetitions in the first test using adult insects and six repetitions in the others. Observations were made daily up to the fifth day, aiming to evaluate the mortality of the insects. All the tested extracts resulted in an effective control of the larvae of M. ochroloma. In relation to the adult insects, only the extracts of tobacco powder and DalNeem showed effective control.

  11. Identification of a rice gene (Bph 1) conferring resistance to brown planthopper (Nilaparvata lugens Stal) using STS markers.

    Science.gov (United States)

    Kim, Suk-Man; Sohn, Jae-Keun

    2005-08-31

    This study was carried out to identify a high-resolution marker for a gene conferring resistance to brown planthopper (BPH) biotype 1, using japonica type resistant lines. Bulked segregant analyses were conducted using 520 RAPD primers to identify RAPD fragments linked to the BPH resistance gene. Eleven RAPDs were shown to be polymorphic amplicons between resistant and susceptible progeny. One of these primers, OPE 18, which amplified a 923 bp band tightly linked to resistance, was converted into a sequence-tagged-site (STS) marker. The STS marker, BpE18-3, was easily detectable as a dominant band with tight linkage (3.9cM) to Bph1. It promises to be useful as a marker for assisted selection of resistant progeny in backcross breeding programs to introgress the resistance gene into elite japonica cultivars.

  12. Inheritance Mode and Realized Heritability of Resistance to Imidacloprid in the Brown Planthopper, Nilaparvata lugens (Stal) (Homoptera: Delphacidae)

    Science.gov (United States)

    BACKGROUND: The brown planthopper, Nilaparvata lugens (Stål) is a serious pest which causes enormous losses to the rice crop in Asia. The genetic basis of imidacloprid resistance was investigated in N. lugens. RESULTS: The resistant strain, selected for imidacloprid resistance from a laboratory pop...

  13. The use of P-32 for determining varietal resistance of rice to brown planthopper (Nilaparvata lugens stal)

    International Nuclear Information System (INIS)

    Kuswadi, Achmad Nasroh

    1981-01-01

    The resistance was assessed uased on the feeding activities of the insect on 15-day old seedling of six test varietes namely TN 1, Asahan, Brantas, Citarum, Serayu and Mudgo. A level of 175 μCi per seedling appeared to give sufficiently high absorption of radiophosphorus by the brown planthoppers. The level of radioactivity in the brown planthopper fed for 24 hours on labelled rice plants appeared to be correlated with the susceptibility of the rice plant to brown planthopper. The radioactivity in the honeydew of those hoppers was less correlated with the rice susceptibility. The promising resistance screening method using P-32 tracer is thus more reliable when the radioactivity is detected in the insect rather than in the honeydew. (author)

  14. Uptake of 14C-carbofuran from rice plants by brown planthopper (nilaparvata lugens stal) and green leafhopper (Nephotettix virencence)

    International Nuclear Information System (INIS)

    Sumatra, M.; Anwar, E.; Kuswadi, A.N.; Soekarna, D.

    1988-01-01

    An experiment was carried out to determine the amount of 14-C-carbofuran taken up by brown planthopper (BPH) and green leafhopper (GLH) from ride plants containing 14-C-carbofuran. The roots of 30 days old rice plants were immersed in Kimura B solution containing carbofuran (0.6ug/ml) with activity of 18600 pCi/ml. After 3 days, 20 BPH and 20 GLH released onto the rice stems and leaves. The mortalities of BPH and GLH were similar after 24 and 48 hours of the release. The average radioactivity found in living GLH was 3.5 times of those found in living GLH was 3.5 times of those found in living BPH. And in dead GLH was 3.2 times on those in dead BPH. Radioactivity in rice leaves was 3.5 times of those in stems. This layer chromatograph of extracts of Kimura B solution, stems, and leaves showed that small amounts of carbofuran had degraded to substances like 3-OH-carbofuran and 3-keto-carbofuran. The percentage of radioactivity found as carbofuran decreased with time, while the amount of 3-ket-carbofuran increased. (authors). 6 refs, 2 figs, 6 tab

  15. Estudo comparativo do ciclo evolutivo de Rhodnius neglectus alimentados em pombos ou camundongos

    Directory of Open Access Journals (Sweden)

    Liléia Diotaiuti

    1987-06-01

    Full Text Available Baseados no encontro de 77,2% de reação de precipitina positiva para soro antiave de R. neglectus capturados em palmeiras da periferia de Belo Horizonte, estudamos o ciclo evolutivo de uma colonia recém-estabelecida no laboratório alimentada com sangue de pombo ou camundongo, na expectativa de demonstrarmos maior adaptação deste triatomíneo ao sangue da ave. Para comparação, estudamos o ciclo evolutivo destes insetos numa colônia há muito mantida em insetário. Nossos resultados mostram um desenvolvimento mais rápido da colônia recém- estabelecida, assim como do lote de triatomíneos alimentado em camundongo. Esses achados sugerem menor potencial biológico para triatomíneos criados por longo tempo em insetário em comparação a novas colônias. Sendo as aves os principais habitantes das palmeiras, a aparente preferência alimentar por sangue de aves demonstrada pela reação de precipitina parece ser circunstancial e não seletiva na busca do sangue com o qual o triatomíneo obteria melhor desenvolvimento.Feeding pattems of R. neglectus collected in palm trees around Belo Horizonte (Minas Gerais, Brazil were investigated. Precipitin tests showed 77.2% of avian blood. In view of these results, a new colony of R. neglectus established in the laboratory was fed regularly on pigeons or mice, in order to verify a possible better adaptation of this insect to the avian blood. As a control group a colony of R neglectus which has been maintained for several years in the laboratory was also observed. The results show a better development of the “new" colony in comparison with the old one, and of those bugs nourished with mice blood. Such findings suggest a poorer biological potential for triatomines maintained for long time in artificial conditions, in comparison with those living in the natural environment. As birds are the main vertebrate inhabitants of palm trees (the natural ecotope of R neglectus, the apparent feeding preference of this species for avian blood seems to be merely circumstancial and not related to a better biological performance provided by this kind of blood.

  16. Epidemiología de la enfermedad de Chagas en el municipio Andrés Eloy Blanco, Lara, Venezuela: infestación triatomínica y seroprevalencia en humanos Epidemiology of Chagas disease in Andrés Eloy Blanco, Lara, Venezuela: triatomine infestation and human seroprevalence

    Directory of Open Access Journals (Sweden)

    Claudina Rodríguez-Bonfante

    2007-05-01

    Full Text Available Se realizó un despistaje serológico y recolección de vectores en cuatro comunidades rurales del municipio Andrés Eloy Blanco, Estado Lara, Venezuela. La muestra fue escogida en forma sistemática y aleatoria basada en conglomerados familiares. Se muestrearon 869 habitantes para determinar anticuerpos anti-Trypanosoma cruzi y anti-Leishmania sp. por inmunofluorescencia indirecta, aceptando como positivo diluciones > a 1:32 para anticuerpos anti-T. cruzi no reactivos para antígenos de Leishmania sp., obteniendo una frecuencia de anticuerpos en la muestra de 6,9% (n = 60; de los cuales 46,66% son femeninos, 53,33% masculinos y 60% mayores de 40 años. Se observó que 5 (8,33% de los seropositivos eran menores de 10 años y 10 (16,66% menores de 20 años. Rhodnius prolixus y Panstrongylus geniculatus fueron los triatominos capturados, con índice de infestación de 1,9 y 10,54%, índice de colonización, del 0 y 18,18% en las viviendas infestadas e índice de infección a T. cruzi del 20 y 5,07%, respectivamente. Los resultados sugieren que existe una transmisión activa de la enfermedad de Chagas en el Municipio Andrés Eloy Blanco en las últimas dos décadas y que P. geniculatus está substituyendo a R. prolixus como vector de la enfermedad de Chagas.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 > 1:32 for anti-T. cruzi antibody and non-reactive to Leishmania sp. antigen, revealing an antibody frequency of 6.9% (n = 60, of whom 46.66% were females and 53.33% males and 60% were over 39 years of age. Some 5 (8.33% seropositive individuals were under 10 years of age and 10 (16.66% under 20 years. Rhodnius prolixus and

  17. Febre maculosa das Montanhas Rochosas: ensaios negativos de transmissão experimental do virus por Triatomideos Rocky Mountain spotted fever: failure of Triatomid bugs to transmit the virus experimentally

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    Cornelius B. Philip

    1938-01-01

    Full Text Available 1. - As seguintes especies de Triatomideos não puderam transmitir pela picada o virus da febre maculosa das Montanhas Rochosas a cobayas normaes, nos seguintes prazos após a sucção de animal infectado: Eutriatoma uhleri, 33, 47, 75 e 141 dias (1 exemplar; Triatoma protracta, 15 e 37 dias (1 exemplar, Triatoma infestans, 8 dias (15 exemplares, e Rhodnius prolixus, 2 dias (1 exemplar. Foi demonstrado por inoculaçao que o ultimo insecto ainda continha o virus vivo. 2. - Experiencias de transmissão mechanica, por picada interrompida em animal infectado e continuada immediatamente em animal são, foram tambem negativas, com as especies T. protracta e R. prolixus. Um unico insecto da primeira especie picou 2 vezes cada animal, emquanto que 22 exemplares da segunda especie picaram de 1 a 3 vezes cada cobaya. 3. - A inoculação de gottas de dejecções de um R. prolixus eliminadas 2 dias depois de sugar animal infectado, não produziu a infecção em cobaya normal, não obstante ter sido demonstrada a presença do virus no organismo do barbeiro, por inoculação do conteúdo estomacal em outra cobaya. 4. - Foram feitas experiencias para determinar o tempo de sobrevivencia do virus nos barbeiros, inoculando-se conteúdo intestinal a diversos intervallos depois da sucção de cobayas infectadas, com os seguintes resultados: T. infestans: positivo 1 vez em 24 horas e 2 vezes em 48 horas; negativo 2 vezes em 72. 96, 120 e 192 horas. P. megistus: positivo 3 vezes em 24 horas, 2 vezes em 48 horas e 1 vez em 72 horas; negativo 1 vez em 72 e 96 horas; resultado duvidoso ou sem valor (infecção intercorrente 1 vez em 48 horas e 2 vezes a 72, 96 e 144 horas cada um. R. prolixus: positivo 1 vez em 24, 48 e 72 horas e negativo em 96 horas. 5. - Em vista dos resultados destas experiencias, feitas com 5 especies pertecentes a 4 generos de Triatomideos, torna-se muito pouco provavel que estes Hemipteros possam transmitir pela picada o virus da febre maculosa

  18. Screening of Fungi for Biological Control of a Triatomine Vector of Chagas Disease: Temperature and Trypanosome Infection as Factors.

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    Aline R M Garcia

    2016-11-01

    Full Text Available Entomopathogenic fungi have been investigated as an alternative tool for controlling various insects, including triatomine vectors of the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. Here we tested the pathogenicity and virulence of ten isolates of the fungi Metarhizium spp. and Beauveria bassiana against Rhodnius prolixus and found all of the isolates to be virulent. We used two isolates (URPE-11 Metarhizium anisopliae and ENT-1 Beauveria bassiana for further screening based on their prolific sporulation in vitro (an important property of fungal biopesticides. We characterized their virulences in a dose-response experiment and then examined virulence across a range of temperatures (21, 23, 27 and 30°C. We found isolate ENT-1 to maintain higher levels of virulence over these temperatures than URPE-11. We therefore used B. bassiana ENT-1 in the final experiment in which we examined the survival of insects parasitized with T. cruzi and then infected with this fungus (once again over a range of temperatures. Contrary to our expectations, the survival of insects challenged with the pathogenic fungus was greater when they had previously been infected with the parasite T. cruzi than when they had not (independent of temperature. We discuss these results in terms of aspects of the biologies of the three organisms. In practical terms, we concluded that, while we have fungal isolates of potential interest for development as biopesticides against R. prolixus, we have identified what could be a critical problem for this biological tool: the parasite T. cruzi appears to confer a measure of resistance to the insect against the potential biopesticide agent so use of this fungus as a biopesticide could lead to selection for vector competence.

  19. Insecticide resistance in vector Chagas disease: evolution, mechanisms and management.

    Science.gov (United States)

    Mougabure-Cueto, Gastón; Picollo, María Inés

    2015-09-01

    Chagas disease is a chronic parasitic infection restricted to America. The disease is caused by the protozoa Trypanosoma cruzi, which is transmitted to human through the feces of infected triatomine insects. Because no treatment is available for the chronic forms of the disease, vector chemical control represents the best way to reduce the incidence of the disease. Chemical control has been based principally on spraying dwellings with insecticide formulations and led to the reduction of triatomine distribution and consequent interruption of disease transmission in several areas from endemic region. However, in the last decade it has been repeatedly reported the presence triatomnes, mainly Triatoma infestans, after spraying with pyrethroid insecticides, which was associated to evolution to insecticide resistance. In this paper the evolution of insecticide resistance in triatomines is reviewed. The insecticide resistance was detected in 1970s in Rhodnius prolixus and 1990s in R. prolixus and T. infestans, but not until the 2000s resistance to pyrthroids in T. infestans associated to control failures was described in Argentina and Bolivia. The main resistance mechanisms (i.e. enhanced metabolism, altered site of action and reduced penetration) were described in the T. infestans resistant to pyrethrods. Different resistant profiles were demonstrated suggesting independent origin of the different resistant foci of Argentina and Bolivia. The deltamethrin resistance in T. infestans was showed to be controlled by semi-dominant, autosomally inherited factors. Reproductive and developmental costs were also demonstrated for the resistant T. infestans. A discussion about resistance and tolerance concepts and the persistence of T. infestans in Gran Chaco region are presented. In addition, theoretical concepts related to toxicological, evolutionary and ecological aspects of insecticide resistance are discussed in order to understand the particular scenario of pyrethroid

  20. NMR Studies of the Dynamics of Nitrophorin 2 Bound to Nitric Oxide†

    Science.gov (United States)

    Muthu, Dhanasekaran; Berry, Robert E.; Zhang, Hongjun; Walker, F. Ann

    2013-01-01

    The Rhodnius nitrophorins are β-barrel proteins of the lipocalin fold with a heme protruding from the open end of the barrel. They are found in the saliva of the blood-sucking insect Rhodnius prolixus, which synthesizes and stores nitric oxide (NO) in the salivary glands, where NO is bound to iron. NO is released by dilution and pH rise when the insect spits its saliva into the tissues of a victim, to aid in obtaining a blood meal. In the adult insect there are four nitrophorins, NP1, NP2, NP3 and NP4. At pH 7.3, NP4 releases NO 17 times faster than does NP2, as measured by stopped-flow kinetics. A number of crystal structures of the least abundant protein, NP4, are available. These structures have been used to propose that two loops between adjacent β-strands at the front opening of the protein, the A-B and G-H loops, determine the rate of NO release. In order to learn how the protein loops contribute to release of NO for each of the nitrophorins, the dynamics of these proteins are being studied in our laboratory. In this work, the NP2-NO complex has been investigated by NMR relaxation measurements to probe the pico- to nanosecond and micro- to millisecond time scale motions at three pH values, 5.0, 6.5, and 7.3. It is found that at pH 5.0 and 6.5, NP2-NO is rigid and only a few residues in the loop regions show dynamics, while at pH 7.3 somewhat more dynamics, particularly of the A-B loop, are observed. Comparison to other lipocalins shows that all are relatively rigid, and that the dynamics of lipocalins in general are much more subtle than those of mainly α-helical proteins. PMID:24116947

  1. Cardiac contractility structure-activity relationship and ligand-receptor interactions; the discovery of unique and novel molecular switches in myosuppressin signaling.

    Directory of Open Access Journals (Sweden)

    Megan Leander

    Full Text Available Peptidergic signaling regulates cardiac contractility; thus, identifying molecular switches, ligand-receptor contacts, and antagonists aids in exploring the underlying mechanisms to influence health. Myosuppressin (MS, a decapeptide, diminishes cardiac contractility and gut motility. Myosuppressin binds to G protein-coupled receptor (GPCR proteins. Two Drosophila melanogaster myosuppressin receptors (DrmMS-Rs exist; however, no mechanism underlying MS-R activation is reported. We predicted DrmMS-Rs contained molecular switches that resembled those of Rhodopsin. Additionally, we believed DrmMS-DrmMS-R1 and DrmMS-DrmMS-R2 interactions would reflect our structure-activity relationship (SAR data. We hypothesized agonist- and antagonist-receptor contacts would differ from one another depending on activity. Lastly, we expected our study to apply to other species; we tested this hypothesis in Rhodnius prolixus, the Chagas disease vector. Searching DrmMS-Rs for molecular switches led to the discovery of a unique ionic lock and a novel 3-6 lock, as well as transmission and tyrosine toggle switches. The DrmMS-DrmMS-R1 and DrmMS-DrmMS-R2 contacts suggested tissue-specific signaling existed, which was in line with our SAR data. We identified R. prolixus (RhpMS-R and discovered it, too, contained the unique myosuppressin ionic lock and novel 3-6 lock found in DrmMS-Rs as well as transmission and tyrosine toggle switches. Further, these motifs were present in red flour beetle, common water flea, honey bee, domestic silkworm, and termite MS-Rs. RhpMS and DrmMS decreased R. prolixus cardiac contractility dose dependently with EC50 values of 140 nM and 50 nM. Based on ligand-receptor contacts, we designed RhpMS analogs believed to be an active core and antagonist; testing on heart confirmed these predictions. The active core docking mimicked RhpMS, however, the antagonist did not. Together, these data were consistent with the unique ionic lock, novel 3-6 lock

  2. Estrategia para determinar la línea base en áreas de interrupción vectorial de la enfermedad de Chagas

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    Diego Montenegro

    Full Text Available RESUMEN Objetivos Presentar una estrategia para determinar la línea de base en áreas endémicas en el proceso de interrupción vectorial de la enfermedad de Chagas (ECh. Métodos Con un cuestionario socioambiental y una encuesta entomológica, se evaluaron las condiciones físicas de los domicilios, el conocimiento de los habitantes sobre la ECh, los indicadores entomológicos de triatominos y la relación estadística entre estas variables. Resultados Existe colonización e infección natural con Trypanosoma cruzi en Rhodnius prolixus, el principal vector de la ECh en Colombia. La colonización estuvo relacionada con casas de techos de hojas de palma y paredes de adobe o bahareque. Se encontró el vector Panstrongylus geniculatus con hábitos de colonización. Casi 50% de la población encuestada asociaba el término ECh con una enfermedad humana y 37%, con los triatominos. Conclusiones R. prolixus puede considerarse el principal vector de T. cruzi en ambientes domésticos y el proceso de interrupción vectorial es factible dentro del municipio priorizado. Se necesitan nuevos estudios que comprueben la existencia de poblaciones silvestres de R. prolixus que puedan afectar las etapas futuras del proceso y demostrar si hay una participación de P. geniculatus en la dinámica de transmisión de T. cruzi. Los anteriores escenarios pueden ser viabilizados con la inclusión de los habitantes en todo el proceso, ya que han sido altamente sensibles en la detección de vectores dentro de sus casas. El diseño del estudio aquí presentado puede ser adaptado en otras áreas endémicas de la Región de las Américas.

  3. Distribution and activity of a Dippu DH31-like peptide in the large milkweed bug Oncopeltus fasciatus.

    Science.gov (United States)

    Te Brugge, V A; Orchard, I

    2008-02-01

    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 DH31-like immunoreactivity in the central nervous system (CNS) and gut of O. fasciatus 5th instars. As well, DH31-like material was quantified and partially purified from the CNS of 5th instar O. fasciatus using reversed-phase liquid chromatography (RPLC) and monitored with an enzyme-linked immunosorbent assay (ELISA). When tested on O. fasciatus 5th instar Malpighian tubules, DH31-like peptides significantly increased the rate of secretion over saline controls. The results suggest that there is a DH31-like peptide(s) present in the CNS of O. fasciatus and that this peptide may play a role in the control of Malpighian tubule secretion.

  4. Geographic distribution and morphometric differentiation of Triatoma nitida usinger 1939 (Hemiptera: Reduviidae: Triatominae in Guatemala

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    Monroy Carlota

    2003-01-01

    Full Text Available Triatoma nitida was found in 14 (0.4% out of 3,726 houses located in six departments across Guatemala, which were surveyed from 1994 to 1998 by the man-hour collection method. Compared to previous information, the distribution of T. nitida in Guatemala has increased from five to nine departments; the species is present in mild climates at altitudes from 960 to 1,500 m. Fourteen percent of the intradomestic T. nitida were infected with Trypanosoma cruzi. The species was often found in conjunction with other triatomines (T. dimidiata and Rhodnius prolixus. The domestic and peridomestic presence of T. nitida in Guatemala was rare, but occasionally this species was colonizing human-made constructions. T. nitida appears to have a low importance as Chagas disease vector in Guatemala, as indicated by its scarce presence in the domestic habitats and defecation patterns. However, it clearly has potential to become a Chagas vector so we recommend an on-going study of the intradomestic presence of T. nitida following the control programs in Guatemala. Morphometric analysis of 47 T. nitida males from three localities showed quantitative differences between the populations, which indicates that geographic distance is an important factor in the structuring of T. nitida populations.

  5. Anti-complement activity in the saliva of phlebotomine sand flies and other haematophagous insects.

    Science.gov (United States)

    Cavalcante, R R; Pereira, M H; Gontijo, N F

    2003-07-01

    The saliva of haematophagous insects has a series of pharmacological activities which may favour blood feeding. In the present study, an inhibitory effect on the complement system was observed in salivary extracts obtained from the phlebotomine sand flies Lutzomyia longipalpis and Lu. migonei. Saliva from Lu. longipalpis was capable of inhibiting both the classical and alternative pathways, while that from Lu. migonei acted only on the former. Other haematophagous insect species were screened for inhibition of the classical pathway. The triatomine bugs Panstrongylus megistus, Triatoma brasiliensis and Rhodnius prolixus were also able to inhibit the classical pathway whereas the mosquito Aedes aegyti and flea Ctenocephalides felis were not. The activity of Lu. longipalpis saliva on the classical pathway was partially characterized. The inhibitor is a protein of Mr 10000-30000 Da, which is very resistant to denaturation by heat. The inhibition of the complement system by phlebotomine sand flies may have a role in the transmission of Leishmania to the vertebrate hosts. The inhibitor molecule is thus a promising component of a vaccine to target salivary immunomodulators.

  6. A revision of thirteen species of Triatominae (Hemiptera: Reduviidae vectors of Chagas disease in Mexico

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    Salazar-Schettino Paz Maria

    2010-10-01

    Full Text Available Vectors of Trypanosoma cruzi, parasite responsible for Chagas disease, are divided in intradomestic, peridomestic and sylvatic. The intradomestic are Triatoma barberi and Triatoma dimidiata, two species that represent the highest health risk among the Mexican population. Triatoma dimidiata is a species found mainly inside human habitats, but in Yucatan, it corresponds to the peridomicile vectors. Also in the peridomicile most of Chagas disease vectors are found: Meccus bassolsae, M. longipennis, M. mazzottii, M pallidipennis, M. phyllosomus, M picturata, Triatoma gerstaeckeri, T mexicana, T rubida, Dipetalogaster máxima (the last two are in the process of becoming adapted to the domicile, Panstrongylus rufotuberculatus which occasionally enters the domicile in its adult stage, and Rhodnius prolixus, which is practically controlled in the country. Peridomestic vectors are of lower risk in the transmission dynamics, as compared to the intradomestic ones. For the control of the intradomestic vectors, health education programs, improvements of housing, and the use of pesticides are essential To control the peridomestic vectors, health education programs are required, as well as the use of mosquito nets on doors and windows and around beds, aside from cementing the stone wall fences.

  7. Uso de nuevas herramientas para el control de triatominos en diferentes situaciones entomológicas en el continente americano

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    Oliveira Filho Alfredo M.

    1997-01-01

    Full Text Available Se relatan los resultados obtenidos en el terreno seis meses y dos años post-tratamiento con las nuevas herramientas para el control de triatominos desarrolladas con apoyo de la OMS/TDR, o sea, a pinturas insecticidas, una suspensión emulsionable de lenta liberación conteniendo el 8,3% de malathion, aplicada por rociamiento; b potes fumígenos que, después de encendidos, echan humos que contienen cypermetrina y DDVP; c cajas sensoras para detección de triatominos. Los ensayos en el terreno fueron realizados en Chile, Honduras y Paraguay contra tres especies principales de vectores de la enfermedad de Chagas - Triatoma infestans, T. dimidiata y Rhodnius prolixus, según el protocolo elaborado por un comité de expertos de la OMS. Los resultados indican que las pinturas insecticidas constituyen un eficaz medio de control de estos vectores en cualquiera de las condiciones estudiadas, sea en el domicilio, sea en el peridomicilio, manteniendo los porcentajes de infestación muy próximos a cero. Comparaciones preliminares de la técnica de cajas sensoras para detección de casas infestadas por triatominos, con la búsqueda hecha por personal entrenado (hora/hombre indican esta última como la mas apropiada.

  8. Substrate texture properties induce triatomine probing on bitten warm surfaces

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    Lorenzo Marcelo G

    2011-06-01

    Full Text Available Abstract Background In this work we initially evaluated whether the biting process of Rhodnius prolixus relies on the detection of mechanical properties of the substrate. A linear thermal source was used to simulate the presence of a blood vessel under the skin of a host. This apparatus consisted of an aluminium plate and a nickel-chrome wire, both thermostatized and presented at 33 and 36°C, respectively. To evaluate whether mechanical properties of the substrate affect the biting behaviour of bugs, this apparatus was covered by a latex membrane. Additionally, we evaluated whether the expression of probing depends on the integration of bilateral thermal inputs from the antennae. Results The presence of a latex cover on a thermal source induced a change in the biting pattern shown by bugs. In fact, with latex covered sources it was possible to observe long bites that were never performed in response to warm metal surfaces. The total number of bites was higher in intact versus unilaterally antennectomized insects. These bites were significantly longer in intact than in unilaterally antennectomized insects. Conclusions Our results suggest that substrate recognition by simultaneous input through thermal and mechanical modalities is required for triggering maxillary probing activity.

  9. Lysophosphatidylcholine: A Novel Modulator of Trypanosoma cruzi Transmission

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    Mário A. C. Silva-Neto

    2012-01-01

    Full Text Available Lysophosphatidylcholine is a bioactive lipid that regulates a large number of cellular processes and is especially present during the deposition and infiltration of inflammatory cells and deposition of atheromatous plaque. Such molecule is also present in saliva and feces of the hematophagous organism Rhodnius prolixus, a triatominae bug vector of Chagas disease. We have recently demonstrated that LPC is a modulator of Trypanosoma cruzi transmission. It acts as a powerful chemoattractant for inflammatory cells at the site of the insect bite, which will provide a concentrated population of cells available for parasite infection. Also, LPC increases macrophage intracellular calcium concentrations that ultimately enhance parasite invasion. Finally, LPC inhibits NO production by macrophages stimulated by live T. cruzi, and thus interferes with the immune system of the vertebrate host. In the present paper, we discuss the main signaling mechanisms that are likely used by such molecule and their eventual use as targets to block parasite transmission and the pathogenesis of Chagas disease.

  10. Mitochondrial dysfunction in Trypanosoma cruzi: the role of Serratia marcescens prodigiosin in the alternative treatment of Chagas disease

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    Triana Omar

    2011-05-01

    Full Text Available Abstract Background Chagas disease is a health threat for many people, mostly those living in Latin America. One of the most important problems in treatment is the limitation of existing drugs. Prodigiosin, produced by Serratia marcescens (Rhodnius prolixus endosymbiont, belongs to the red-pigmented bacterial prodiginine family, which displays numerous biological activities, including antibacterial, antifungal, antiprotozoal, antimalarial, immunosuppressive, and anticancer properties. Here we describe its effects on Trypanosoma cruzi mitochondria belonging to Tc I and Tc II. Results Parasites exposed to prodigiosin altered the mitochondrial function and oxidative phosphorylation could not have a normal course, probably by inhibition of complex III. Prodigiosin did not produce cytotoxic effects in lymphocytes and Vero cells and has better effects than benznidazole. Our data suggest that the action of prodigiosin on the parasites is mediated by mitochondrial structural and functional disruptions that could lead the parasites to an apoptotic-like cell death process. Conclusions Here, we propose a potentially useful trypanocidal agent derived from knowledge of an important aspect of the natural life cycle of the parasite: the vector-parasite interaction. Our results indicate that prodigiosin could be a good candidate for the treatment of Chagas disease.

  11. Catalase expression impairs oxidative stress-mediated signalling in Trypanosoma cruzi.

    Science.gov (United States)

    Freire, Anna Cláudia Guimarães; Alves, Ceres Luciana; Goes, Grazielle Ribeiro; Resende, Bruno Carvalho; Moretti, Nilmar Silvio; Nunes, Vinícius Santana; Aguiar, Pedro Henrique Nascimento; Tahara, Erich Birelli; Franco, Glória Regina; Macedo, Andréa Mara; Pena, Sérgio Danilo Junho; Gadelha, Fernanda Ramos; Guarneri, Alessandra Aparecida; Schenkman, Sergio; Vieira, Leda Quercia; Machado, Carlos Renato

    2017-09-01

    Trypanosoma cruzi is exposed to oxidative stresses during its life cycle, and amongst the strategies employed by this parasite to deal with these situations sits a peculiar trypanothione-dependent antioxidant system. Remarkably, T. cruzi's antioxidant repertoire does not include catalase. In an attempt to shed light on what are the reasons by which this parasite lacks this enzyme, a T. cruzi cell line stably expressing catalase showed an increased resistance to hydrogen peroxide (H2O2) when compared with wild-type cells. Interestingly, preconditioning carried out with low concentrations of H2O2 led untransfected parasites to be as much resistant to this oxidant as cells expressing catalase, but did not induce the same level of increased resistance in the latter ones. Also, presence of catalase decreased trypanothione reductase and increased superoxide dismutase levels in T. cruzi, resulting in higher levels of residual H2O2 after challenge with this oxidant. Although expression of catalase contributed to elevated proliferation rates of T. cruzi in Rhodnius prolixus, it failed to induce a significant increase of parasite virulence in mice. Altogether, these results indicate that the absence of a gene encoding catalase in T. cruzi has played an important role in allowing this parasite to develop a shrill capacity to sense and overcome oxidative stress.

  12. Eco-epidemiological aspects of Trypanosoma cruzi, Trypanosoma rangeli and their vector (Rhodnius pallescens in Panama Generalidades do Trypanosoma cruzi, do Trypanosoma rangeli e do seu vetor (Rhodnius pallescens no Panamá

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    Ana Maria de Vasquez

    2004-08-01

    Full Text Available The eco-epidemiology of T. cruzi infection was investigated in the Eastern border of the Panama Canal in Central Panama. Between 1999 and 2000, 1110 triatomines were collected: 1050 triatomines (94.6% from palm trees, 27 (2.4% from periurban habitats and 33 (3.0% inside houses. All specimens were identified as R. pallescens. There was no evidence of vector domiciliation. Salivary glands from 380 R. pallescens revealed a trypanosome natural infection rate of 7.6%, while rectal ampoule content from 373 triatomines was 45%. Isoenzyme profiles on isolated trypanosomes demonstrated that 85.4% (n = 88 were T. cruzi and 14.6% (n = 15 were T. rangeli. Blood meal analysis from 829 R. pallescens demonstrated a zoophilic vector behavior, with opossums as the preferential blood source. Seroprevalence in human samples from both study sites was less than 2%. Our results demonstrate that T. cruzi survives in the area in balanced association with R. pallescens, and with several different species of mammals in their natural niches. However, the area is an imminent risk of infection for its population, consequently it is important to implement a community educational program regarding disease knowledge and control measures.A epidemiologia da infecção do T. cruzi foi investigada na margem oriental do canal do Panamá, na região central da Republica do Panamá. A informação obtida durante o estudo avaliou fatores de risco da doença de Chagas nesta área. Entre 1999 e 2000, 1110 triatomíneos foram coletados: 1050 triatomíneos (94,6% em palmeiras, 27 (2,4% em habitats periurbanos e 33 (3,0% no interior de casas. Todos os espécimens foram identificados como R. pallescens. Não havia nenhuma evidência de domiciliação do vetor. O exame de glândulas salivares de 380 R. pallescens revelaram taxa de infecção natural por Trypanosoma de 7,6%, mas o conteúdo da ampola rectal de 373 triatomíneos mostrou 45% de positividade. Os perfis de isoenzimas em Trypanosomas isolados demonstraram que 85,4% (n = 88 eram T. cruzi e 14,6% (n = 15 eram T. rangeli. A análise da refeição de sangue de 829 R. pallescens demonstrou comportamento zoofílico do vetor, sendo os gambás a fonte preferencial de sangue. Soroprevalência nos seres humanos de ambos locais de estudo foi menos que 2%. Nossos resultados demonstram que T. cruzi sobrevive na área em associação equilibrada com R. pallescens e com diversas espécies diferentes de mamíferos em seus nichos naturais. Entretanto, a área é um risco eminente de infecção para sua população, pelo que é importante executar um programa educacional na comunidade a respeito das medidas, do conhecimento e do controle da doença.

  13. Prokrastinace jako stalý problém mezi studenty: analýza situace v Jihomoravském regionu

    OpenAIRE

    Slezar, Pavel

    2014-01-01

    This bachelor thesis deals with a problem of chronic procrastination which makes people, especially students, to postpone given tasks. This behavior leads to stress, decrease of self-esteem and in poor results. This work focuses on academic procrastination among students in South Moravian region. The theoretical part shows different views from different researchers on procrastination, what types of procrastinations and what kind of procrastinators are there, what are the causes and how to dea...

  14. Genomic insights into the glutathione S-transferase gene family of two rice planthoppers, Nilaparvata lugens (Stal and Sogatella furcifera (Horvath (Hemiptera: Delphacidae.

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    Wen-Wu Zhou

    Full Text Available BACKGROUND: Glutathione S-transferase (GST genes control crucial traits for the metabolism of various toxins encountered by insects in host plants and the wider environment, including insecticides. The planthoppers Nilaparvata lugens and Sogatella furcifera are serious specialist pests of rice throughout eastern Asia. Their capacity to rapidly adapt to resistant rice varieties and to develop resistance to various insecticides has led to severe outbreaks over the last decade. METHODOLOGY/PRINCIPAL FINDINGS: Using the genome sequence of N. lugens, we identified for the first time the complete GST gene family of a delphacid insect whilst nine GST gene orthologs were identified from the closely related species S. furcifera. Nilaparvata lugens has 11 GST genes belonging to six cytosolic subclasses and a microsomal class, many fewer than seen in other insects with known genomes. Sigma is the largest GST subclass, and the intron-exon pattern deviates significantly from that of other species. Higher GST gene expression in the N. lugens adult migratory form reflects the higher risk of this life stage in encountering the toxins of non-host plants. After exposure to a sub-lethal dose of four insecticides, chlorpyrifos, imidacloprid, buprofezin or beta-cypermethrin, more GST genes were upregulated in S. furcifera than in N. lugens. RNA interference targeting two N. lugens GST genes, NlGSTe1 and NlGSTm2, significantly increased the sensitivity of fourth instar nymphs to chlorpyrifos but not to beta-cypermethrin. CONCLUSIONS/SIGNIFICANCE: This study provides the first elucidation of the nature of the GST gene family in a delphacid species, offering new insights into the evolution of metabolic enzyme genes in insects. Further, the use of RNA interference to identify the GST genes induced by insecticides illustrates likely mechanisms for the tolerance of these insects.

  15. Biology of Triatominae (Reduviidae Hemiptera from North of Formosa County (Goiás-Brazil I. Length of life cycle of Triatoma sordida (Stal. 1859

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    Dalva A. Mello

    1976-12-01

    Full Text Available In the present paper the life cycle of Triatoma sordida was studied. The mean length from egg to adult was 213 days. The mean length in days from each stage was: 24.3 (± 1.30 for the first. 32.8 (± 1.45 (2nd, 36.1 (± 1.50 (3rd, 44.6 (± 1.85 (4th and 52.0 (± 1.92 (5th. The mean egg incubation períod was 23.2 (± 1.40. Overall mortality was 18.8% and egg viability was 82.5%.Foi estudado no presente trabalho o ciclo biológico do Triatoma sordida A média da duração do ciclo de ovo a adulto foi 213 dias. A média de duração em dias para cada estágio foi 24,3 (± 1,30 para o primeiro, 32,8 (± 1,45 para o segundo, 36,1 (± 1,50 para o terceiro, 44,6 (± 1,85 para o quarto e 52,0 (± 1,92 para o quinto. A média do período de incubação dos ovos foi 23,2 (± 1,40. A mortalidade em todos ps estágios foi 18,8% e a viabilidade dos ovos foi 82,5%.

  16. Efeito de extratos de plantas com atividade inseticida no controle de Microtheca ochroloma Stal (Col.: Chrysomelidae, em laboratório

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    Sônia Thereza Bastos Dequech

    2008-01-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2008v21n1p41 Extratos de plantas com atividade inseticida foram testados no controle de  Microtheca ochroloma (Col.: Chrysomelidae, uma importante praga de brassicáceas nas fases larval e adulta. Duas larvas com três dias de idade, mantidas sob condições de laboratório (T:25ºC, U.R:70% e 14 horas de fotofase, foram colocadas em tubos de vidro contendo folha de  couve-chinesa (Brassica chinensis previamente tratada com extratos aquosos (10% p/v de folha de cinamomo (Melia azedarach, de ramo de  cinamomo e de pó-de-fumo (Nicotiana tabacum. O mesmo procedimento foi repetido em dois ensaios com insetos adultos. No primeiro, foram utilizados todos os extratos anteriormente citados mais o extrato de Dal- Neem (produto comercial à base de Azadirachta indica. No segundo, os insetos foram expostos a extratos de frutos de pimenta malagueta (Capsicum frutescens e de folhas de pitangueira (Eugenia uniflora, de jambolão (Syzygium cuminii e de eucalipto (Eucalyptus sp.. Todos os testes constaram de 10 insetos por tratamento, com cinco repetições no primeiro ensaio com insetos adultos e com seis repetições nos demais. As  observações foram realizadas diariamente até o quinto dia, objetivando avaliar a mortalidade dos insetos. Todos os extratos testados  resultaram num controle efetivo de larvas de M.ochroloma.Em  relação aos insetos adultos, apenas os extratos de pó-de-fumo e de Dal- Neem apresentaram efi ciência de controle.

  17. Peridomiciliary colonies of Triatoma vitticeps (Stal, 1859 (Hemiptera, Reduviidae, Triatominae infected with Trypanosoma cruzi in rural areas of the state of Espírito Santo, Brazil

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    Claudiney Biral dos Santos

    2005-08-01

    Full Text Available In Brazil, the colonization of human dwellings by triatomines occurs in areas with native vegetation of the caatinga or cerrado types. In areas of Atlantic forest such as in the Brazilian state of Espírito Santo, there are no species adapted to live in human habitations. The few autochthonous cases of Chagas disease encountered in Espírito Santo have been attributed to adult specimens of Triatoma vitticeps that invade houses from forest remnants. In recent years, the entomology unit of the Espírito Santo State Health Secretariat has recorded nymphs infected with flagellates similar to Trypanosoma cruzi in rural localities. Entomological surveys were carried out in the residences and outbuildings in which the insects were found, and serological examinations for Chagas disease performed on the inhabitants. Four colonies were found, all associated with nests of opossums (Didelphis aurita, 111 specimens of T. vitticeps, and 159 eggs being collected. All the triatomines presented flagellates in their frass. Mice inoculated with the faeces presented trypomastigotes in the circulating blood and groups of amastigotes in the cardiac muscle fibres. Serological tests performed on the inhabitants were negative for T. cruzi. Even with the intense devastation of the forest in Espírito Santo, there are no indications of change in the sylvatic habits of T. vitticeps. Colonies of this insect associated with opossum nests would indicate an expansion of the sylvatic environment into the peridomicile.

  18. Impact of the invasive brown marmorated stink bug, Halyomorpha halys (Stal) in Mid-Atlantic tree fruit orchards in the United States: case studies of commercial management

    Science.gov (United States)

    Four commercial orchards in the mid-Atlantic region of the United States were surveyed weekly in 2010 and 2011 for the presence of brown marmorated stink bug and the injury caused to both apple and peaches. Among tested sampling techniques, baited pyramid traps yielded the most brown marmorated sti...

  19. Nitrided steel with increased reliability for steam turbine blades of low pressure cylinders; Vysokoazotistaya stal` s povishennoj nadezhdnostni dlya lopatok ha tsilindrov niskogo davleniya parnikh turbin

    Energy Technology Data Exchange (ETDEWEB)

    Andreev, Ch; Lengarski, P [Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. po Metaloznanie i Tekhnologiya na Metalite

    1996-12-31

    A new type of steel has been developed, containing 0.11-0.20% N and less than 0.05% C, the sum of both components being within the range 0.16-0.26%. The metal has an austenite-martensite structure with 10-30% austenite content. Samples obtained by counter-pressure casting have been investigated with respect to the influence of the thermal treatment on mechanical properties. The best properties are obtained when applying hardening by heating at 1050{sup o} C and cooling at 550{sup o} C: fluidity limit R{sub 0}.2>=850 MPa, relative elongation A>=15%, relative shortening Z>=50%, impact viscosity KCU >= 588 kJ/m{sup 2} at critical temperature of brittleness <-40{sup o} C. These properties are combined with high corrosion and wear resistance and make the steel suitable for steam turbine blades. 5 refs., 2 figs., 4 tabs.

  20. Criteria for Return to Sport after Anterior Cruciate Ligament reconstruction with lower reinjury risk (CR'STAL study): protocol for a prospective observational study in France.

    Science.gov (United States)

    Rambaud, Alexandre J M; Semay, Bertrand; Samozino, Pierre; Morin, Jean-Benoît; Testa, Rodolphe; Philippot, Rémi; Rossi, Jérémy; Edouard, Pascal

    2017-06-30

    The decision regarding when to return to sport after an anterior cruciate ligament reconstruction (ACLR) is an important one. Using a variety of subjective and objective parameters, various attempts have been made to determine an optimal timeline for a return to sport after ACLR, but none have been validated.The aim of the present study is therefore to determine which criteria or combination of criteria could allow to return to sport with the lowest possible risk of reinjury. This study is a prospective cohort, single-centre study, with repeated assessments at 6, 9 and 12 months post-ACL surgical reconstruction and including a 3-year follow-up of patients' sporting activity and reinjuries. 275 patients will be included to test explanatory variables. Postural control analysis, knee laxity, questionnaires (International Knee Documentation Committee (IKDC), Tampa Scale of Kinesiophobia-11 (TSK-11), Anterior Cruciate Ligament-Return to Sport After Reinjury (ACL-RSI) and Single Assessment Numeric Evaluation (SANE)), modified Star Excursion Balance Test, running and sprinting biomechanics, Hop Tests and Isokinetic Tests will all be used. The primary outcome will be any reinjury during the follow-up period, defined as a graft rupture, a contralateral ACL rupture or any injury necessitating an interruption of training and requiring a medical consultation. Two groups will be constituted during the follow-up, separating reinjured from non-reinjured patients. In addition, classic analysis and data mining approaches will be used to build predictive models. The results of this study will be disseminated through peer-reviewed publications and scientific presentations. Ethical approval was obtained through the ethics committee of the University Hospital of Saint-Etienne (reference number IRBN522015/CHUSTE). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. Risk assessment of insecticides used in rice on miridbug, Cyrtorhinus lividipennis Reuter, the important predator of brown planthopper, Nilaparvata lugens (Stal.).

    Science.gov (United States)

    Preetha, G; Stanley, J; Suresh, S; Samiyappan, R

    2010-07-01

    The green miridbug, Cyrtorhinus lividipennis, an important natural enemy of the rice brown planthopper (BPH), Nilaparvata lugens plays a major role as a predator in suppressing the pest population. The study assessed the impact of certain potential insecticides used in the rice ecosystem on the miridbug predator and brown planthopper through contact toxicity. Eleven insecticides, including neonicotinoids, diamides, azomethine pyridines, carbamates, pyrethroids, organophosphates and cyclodienes were selected to test their toxicities against the nymphs of C. lividipennis and N. lugens. Median lethal concentration (LC(50)) was determined for each insecticide using an insecticide-coated vial (scintillation) residue bioassay, which revealed BPMC as the highly toxic chemical with an LC(50) of 0.003mga.iL(-1) followed by ethofenprox and clothianidin with LC(50) of 0.006mga.iL(-1) at 48 HAT against C. lividipennis and ethofenprox as the highly toxic chemical with an LC(50) of 0.009mga.iL(-1) followed by clothianidin with an LC(50) of 0.211mga.iL(-1) at 48h after treatment (HAT) against N. lugens. Among the insecticides tested, the cyclodiene compound, endosulfan had the lowest acute contact toxicity (LC(50)=66.65mga.iL(-1) at 48 HAT) to C. lividipennis. Among the insecticides tested, endosulfan, chlorpyriphos, acephate and methyl parathion are regarded as safer to C. lividipennis based on selectivity ratio, hazard quotient and probit substitution method of risk assessments. 2010 Elsevier Ltd. All rights reserved.

  2. Peridomiciliary colonies of Triatoma vitticeps (Stal, 1859) (Hemiptera, Reduviidae, Triatominae) infected with Trypanosoma cruzi in rural areas of the state of Espírito Santo, Brazil

    OpenAIRE

    Santos, Claudiney Biral dos; Ferreira, Adelson Luiz; Leite, Gustavo Rocha; Ferreira, Gabriel Eduardo Melim; Rodrigues, Andressa Alencastre Fuzari; Falqueto, Aloísio

    2005-01-01

    In Brazil, the colonization of human dwellings by triatomines occurs in areas with native vegetation of the caatinga or cerrado types. In areas of Atlantic forest such as in the Brazilian state of Espírito Santo, there are no species adapted to live in human habitations. The few autochthonous cases of Chagas disease encountered in Espírito Santo have been attributed to adult specimens of Triatoma vitticeps that invade houses from forest remnants. In recent years, the entomology unit of the Es...

  3. Fine mapping of the rice Bph1 gene, which confers resistance to the brown planthopper (Nilaparvata lugens stal), and development of STS markers for marker-assisted selection.

    Science.gov (United States)

    Cha, Young-Soon; Ji, Hyeonso; Yun, Doh-Won; Ahn, Byoung-Ohg; Lee, Myung Chul; Suh, Seok-Cheol; Lee, Chun Seok; Ahn, Eok Keun; Jeon, Yong-Hee; Jin, Il-Doo; Sohn, Jae-Keun; Koh, Hee-Jong; Eun, Moo-Young

    2008-08-31

    The brown planthopper (BPH) is a major insect pest in rice, and damages these plants by sucking phloem-sap and transmitting viral diseases. Many BPH resistance genes have been identified in indica varieties and wild rice accessions, but none has yet been cloned. In the present study we report fine mapping of the region containing the Bph1 locus, which enabled us to perform marker-aided selection (MAS). We used 273 F8 recombinant inbred lines (RILs) derived from a cross between Cheongcheongbyeo, an indica type variety harboring Bph1 from Mudgo, and Hwayeongbyeo, a BPH susceptible japonica variety. By random amplification of polymorphic DNA (RAPD) analysis using 656 random 10-mer primers, three RAPD markers (OPH09, OPA10 and OPA15) linked to Bph1 were identified and converted to SCAR (sequence characterized amplified region) markers. These markers were found to be contained in two BAC clones derived from chromosome 12: OPH09 on OSJNBa0011B18, and both OPA10 and OPA15 on OSJNBa0040E10. By sequence analysis of ten additional BAC clones evenly distributed between OSJNBa0011B18 and OSJNBa0040E10, we developed 15 STS markers. Of these, pBPH4 and pBPH14 flanked Bph1 at distances of 0.2 cM and 0.8 cM, respectively. The STS markers pBPH9, pBPH19, pBPH20, and pBPH21 co-segregated with Bph1. These markers were shown to be very useful for marker-assisted selection (MAS) in breeding populations of 32 F6 RILs from a cross between Andabyeo and IR71190, and 32 F5 RILs from a cross between Andabyeo and Suwon452.

  4. The implementation of the case assignment method of patient care at the Dr. A.J. Stals care and rehabilitation centre

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    N.L. Daniels

    1980-09-01

    Full Text Available The modern approach to the care of the mentally retarded in institutional settings is no longer to provide only custiodial care, but to train and rehabilitate each patient to be able to function at his maximal potential. This requires that each resident must have his abilities assessed and a programme implemented for his training, according to his particular needs and capabilities. Residents requiring similar training programmes are therefore grouped together under the care of one nurse, the number of residents in each group depending upon their selfcare skills. The nurse is assigned the responsibility of carrying out the training programme under the supervision of the Ward Sister and with the guidance of the multidisciplinary team under the leadership of the psychiatrist.

  5. Fonte alimentar e potencial vetorial de Triatoma vitticeps (Stal, 1859 com relação à doença de Chagas humana no estado do Espírito Santo, Brasil (Hemiptera, Reduviidae Feeding and vectorial capacity of Triatoma vitticeps (Stal, 1859 in relation with human chagas' disease in Espírito Santo State, Brazil

    Directory of Open Access Journals (Sweden)

    João Carlos Pinto Dias

    1989-01-01

    Full Text Available In paralel with several other epidemiologic and entomologic data of 19 Municipalities of Espírito Santo State, Brazil, the feeding pattern of 222 Triatoma vitticeps is studied through precipitin tests. Very high levels of natural infection with Trypanosoma cruzi are observed in adult insects, in contrast with the abscence or minimum degrees of infection among nymphs and human individuals. The precipitin tests showed the contact of the insects with multiple blood sources, chiefly human and birds, followed by rodents and marsupials. The data suggest that T. vitticeps in spite of being highly antropophilic, become infected by T. cruzi in sylvatic ambient and occasionally invade houses. The species doesn't seem to be - at least until now - a good vector in the domestic cycle of Chagas' disease. Several factors seem to be involved in this conclusion, mainly the low density of the insect in the houses, its hardness to coloniza them, its slowness concerning to suction and defecation and possibly its low susceptibility to different T. cruzi strains.

  6. Ciclo de vida y aspectos poblacionales de Edessa aff. aulacosterna Stal, 1872 (Heteroptera: Pentatomidae chinche del fruto del camu camu (Myrtaceae en zona de restinga, Ucayali, Perú Life cycle and population aspects of camu camu fruit stink bug Edessa aff. aulacosterna Stal, 1872 (Heteroptera: Pentatomidae in restinga zone, Ucayali, Peru

    Directory of Open Access Journals (Sweden)

    José Iannacone

    2007-01-01

    Full Text Available El camu camu es uno de los frutales nativos con gran potencial económico para la agroindustria y agro exportación. Edessa es una de las plagas del camu camu que provoca sequedad en los brotes, y en los frutos una mancha decolorada con círculos concéntricos bien marcados y un punto central al alimentarse. El objetivo del presente trabajo fue determinar el ciclo biológico bajo condiciones de laboratorio y la fluctuación poblacional de Edessa aff. aulacosterna "Chinche del fruto del camu camu" durante enero a noviembre del 2004 en el cultivo de camu camu, en parcelas en desarrollo y producción ubicadas en áreas de restinga inundables en Pucallpa, Ucayali, Perú. Se colectaron huevos, ninfas y adultos procedentes del distrito de Yarinacocha, Pucallpa, Ucayali, Perú para iniciar la crianza artificial. El tiempo de duración del huevo al I estadio ninfal fue 5,1 días. Se encontró un 94,6% de eclosión de los huevos, variando entre 12 hasta 14 huevos por postura. El tiempo transcurrido desde el huevo hasta II estadío fue de 37,3 días y del III al V estadío ninfal fue de 81,9 días. El porcentaje de mortalidad del primer estadio ninfal a adulto fue de 98,1%. Los adultos colectados se localizaron preferentemente sobre las ramas y el tallo de la planta, mientras que las ninfas se encontraron en los brotes tiernos. Con relación a su fluctuación poblacional, solo se registró posturas a lo largo del año en parcelas en producción. No se encontraron diferencias entre ninfas I a V, y adultos de Edessa aff. aulacosterna, entre plantaciones en producción y desarrollo de camu camu. Solo se encontró diferencias entre la época seca y lluviosa en las ninfas de III a V estadio en las plantas de camu camu en desarrollo. Edessa aff. aulacosterna presentó mayormente una distribución contagiosa. El adecuado conocimiento de la bioecología nos permite mejorar la estrategia de control de esta plaga.Camu camu is one of the native fruits with a great economic potential for agroindustry and agro exportation. Edessa is one camu camu pest that produces in dry buds and fruits with a mark decolorated with concentric circles well marked and a central point when they feed. The aim of the current research was to determinate the biological cycle under laboratory conditions and population fluctuations of Edessa aff. aulacosterna. "Camu camu fruit stink bug" during January to November, 2004 in camu-camu culture, in development and production parcels located in flooded areas of restinga in Pucallpa, Ucayali, Peru. Eggs, nymphs and adults were colected to begin artificial rearing proceeding of distrit of Yarinacocha, Pucallpa, Ucayali, Peru. Development time of eggs to 1th nymphal instar was 5.1 days. 94.6% of egg hatchability, varied between 12 until 14 egg-laying was found. The time passed since eggs until III nymphal instar was 37.3 días and of III to V nymphal instar was de 81.9 days. Percentage of mortality of 2nd nymphal instar to adult was 98,1%. Adults collected were localized mainly on branches and stem of the plants, while nymphs were found in delicated buds. In relation to seasonal populations only were registered eggs laying throught the year in parcels in production. Differences between nymphs I to V and adults of Edessa aff. aulacosterna, in production and development plantations were not found. Only differences in dry and wet period in III to V nymphs instar in development camu camu plants were found. Edessa aff. aulacosterna mainly presented a contagious distribution. Suitable knowledge of bioecology of Edessa aff. aulacosterna permit improves strategy of pest control.

  7. Ecologia de triatomíneos e transmissão do Trypanosoma cruzi, com especial referência ao Brasil

    Directory of Open Access Journals (Sweden)

    Mauro Pereira Barreto

    1976-12-01

    ecótopos naturais e artificiais. Embora tenham conseguido adaptar-se com maior ou menor sucesso à habitação humana e suas dependências, são encontradas também em diferentes ecótopos naturais. Além de participar do ciclo silvestre do T. cruzi têm importância no transporte do parasita para os ecótopos artificiais e na infestação inicial ou na reinfestação destes ecótopos livres de insetos pelo expurgo, constituindo também elos na cadeia de transmissão domiciUária da infecção. Exemplos: Panstrongylus megistus, Rhodnius prolixus, Rhodnius pallenscens, Triatoma sórdida, Triatoma brasiliensis, Triatoma maculata, Triatoma pseudomaculata, Triatoma quasayana etc. 5 Triatomíneos bem adotados aos ecótopos artificiais, mas, às vezes, ainda encontrados em focos residuais naturais. São os insetos mais importantes no ciclo domiciiiário do T.cruzi, mas podem, pelo menos em certas áreas, participar do ciclo silvestre da infecção. Exemplo: Triatoma infestans. 6 Triatomíneos estritamente domiciliados. Apesar disto, parecem ter menor importância no ciclo domiciiiário, especialmente na transmissão do T. cruzi ao homem, porque convivem mais com ratos comensais, embora também entrem em contacto com o homem. Exemplo: Triatoma rubrofasciata.On the basis of their ecological behavior the triatomines are distributed into six groups: 1. Typically wild insects, i. e., species that are found only in natural ecotopes, never being collected in human dweellings and their annexes. Consequently they never come into contact with man and domestic, commensal or synantropic mammals, unless they enter the natural foci. But these insects may have a more or less important role in maintaining the wild trypanosome enzooty. Examples: Psammolestes coreodes, Psammolestes tertius, Cavernicola pilosa, Triatoma dispar, Triatoma delpontei and other little known species. 2. Essentially wild insects whose adults occasionally invade human dwellings and their annexes but are unable to

  8. Comparative and functional triatomine genomics reveals reductions and expansions in insecticide resistance-related gene families.

    Science.gov (United States)

    Traverso, Lucila; Lavore, Andrés; Sierra, Ivana; Palacio, Victorio; Martinez-Barnetche, Jesús; Latorre-Estivalis, José Manuel; Mougabure-Cueto, Gaston; Francini, Flavio; Lorenzo, Marcelo G; Rodríguez, Mario Henry; Ons, Sheila; Rivera-Pomar, Rolando V

    2017-02-01

    Triatomine insects are vectors of Trypanosoma cruzi, a protozoan parasite that is the causative agent of Chagas' disease. This is a neglected disease affecting approximately 8 million people in Latin America. The existence of diverse pyrethroid resistant populations of at least two species demonstrates the potential of triatomines to develop high levels of insecticide resistance. Therefore, the incorporation of strategies for resistance management is a main concern for vector control programs. Three enzymatic superfamilies are thought to mediate xenobiotic detoxification and resistance: Glutathione Transferases (GSTs), Cytochromes P450 (CYPs) and Carboxyl/Cholinesterases (CCEs). Improving our knowledge of key triatomine detoxification enzymes will strengthen our understanding of insecticide resistance processes in vectors of Chagas' disease. The discovery and description of detoxification gene superfamilies in normalized transcriptomes of three triatomine species: Triatoma dimidiata, Triatoma infestans and Triatoma pallidipennis is presented. Furthermore, a comparative analysis of these superfamilies among the triatomine transcriptomes and the genome of Rhodnius prolixus, also a triatomine vector of Chagas' disease, and other well-studied insect genomes was performed. The expression pattern of detoxification genes in R. prolixus transcriptomes from key organs was analyzed. The comparisons reveal gene expansions in Sigma class GSTs, CYP3 in CYP superfamily and clade E in CCE superfamily. Moreover, several CYP families identified in these triatomines have not yet been described in other insects. Conversely, several groups of insecticide resistance related enzymes within each enzyme superfamily are reduced or lacking in triatomines. Furthermore, our qRT-PCR results showed an increase in the expression of a CYP4 gene in a T. infestans population resistant to pyrethroids. These results could point to an involvement of metabolic detoxification mechanisms on the high

  9. Comparative and functional triatomine genomics reveals reductions and expansions in insecticide resistance-related gene families.

    Directory of Open Access Journals (Sweden)

    Lucila Traverso

    2017-02-01

    Full Text Available Triatomine insects are vectors of Trypanosoma cruzi, a protozoan parasite that is the causative agent of Chagas' disease. This is a neglected disease affecting approximately 8 million people in Latin America. The existence of diverse pyrethroid resistant populations of at least two species demonstrates the potential of triatomines to develop high levels of insecticide resistance. Therefore, the incorporation of strategies for resistance management is a main concern for vector control programs. Three enzymatic superfamilies are thought to mediate xenobiotic detoxification and resistance: Glutathione Transferases (GSTs, Cytochromes P450 (CYPs and Carboxyl/Cholinesterases (CCEs. Improving our knowledge of key triatomine detoxification enzymes will strengthen our understanding of insecticide resistance processes in vectors of Chagas' disease.The discovery and description of detoxification gene superfamilies in normalized transcriptomes of three triatomine species: Triatoma dimidiata, Triatoma infestans and Triatoma pallidipennis is presented. Furthermore, a comparative analysis of these superfamilies among the triatomine transcriptomes and the genome of Rhodnius prolixus, also a triatomine vector of Chagas' disease, and other well-studied insect genomes was performed. The expression pattern of detoxification genes in R. prolixus transcriptomes from key organs was analyzed. The comparisons reveal gene expansions in Sigma class GSTs, CYP3 in CYP superfamily and clade E in CCE superfamily. Moreover, several CYP families identified in these triatomines have not yet been described in other insects. Conversely, several groups of insecticide resistance related enzymes within each enzyme superfamily are reduced or lacking in triatomines. Furthermore, our qRT-PCR results showed an increase in the expression of a CYP4 gene in a T. infestans population resistant to pyrethroids. These results could point to an involvement of metabolic detoxification mechanisms

  10. Automated segmentation of synchrotron radiation micro-computed tomography biomedical images using Graph Cuts and neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Alvarenga de Moura Meneses, Anderson, E-mail: ameneses@ieee.org [Radiological Sciences Laboratory, Rio de Janeiro State University, Rua Sao Francisco Xavier 524, CEP 20550-900, RJ (Brazil); Giusti, Alessandro [IDSIA (Dalle Molle Institute for Artificial Intelligence), University of Lugano (Switzerland); Pereira de Almeida, Andre; Parreira Nogueira, Liebert; Braz, Delson [Nuclear Engineering Program, Federal University of Rio de Janeiro, RJ (Brazil); Cely Barroso, Regina [Laboratory of Applied Physics on Biomedical Sciences, Physics Department, Rio de Janeiro State University, RJ (Brazil); Almeida, Carlos Eduardo de [Radiological Sciences Laboratory, Rio de Janeiro State University, Rua Sao Francisco Xavier 524, CEP 20550-900, RJ (Brazil)

    2011-12-21

    Synchrotron Radiation (SR) X-ray micro-Computed Tomography ({mu}CT) enables magnified images to be used as a non-invasive and non-destructive technique with a high space resolution for the qualitative and quantitative analyses of biomedical samples. The research on applications of segmentation algorithms to SR-{mu}CT is an open problem, due to the interesting and well-known characteristics of SR images for visualization, such as the high resolution and the phase contrast effect. In this article, we describe and assess the application of the Energy Minimization via Graph Cuts (EMvGC) algorithm for the segmentation of SR-{mu}CT biomedical images acquired at the Synchrotron Radiation for MEdical Physics (SYRMEP) beam line at the Elettra Laboratory (Trieste, Italy). We also propose a method using EMvGC with Artificial Neural Networks (EMANNs) for correcting misclassifications due to intensity variation of phase contrast, which are important effects and sometimes indispensable in certain biomedical applications, although they impair the segmentation provided by conventional techniques. Results demonstrate considerable success in the segmentation of SR-{mu}CT biomedical images, with average Dice Similarity Coefficient 99.88% for bony tissue in Wistar Rats rib samples (EMvGC), as well as 98.95% and 98.02% for scans of Rhodnius prolixus insect samples (Chagas's disease vector) with EMANNs, in relation to manual segmentation. The techniques EMvGC and EMANNs cope with the task of performing segmentation in images with the intensity variation due to phase contrast effects, presenting a superior performance in comparison to conventional segmentation techniques based on thresholding and linear/nonlinear image filtering, which is also discussed in the present article.

  11. NMR studies of the dynamics of high-spin nitrophorins: comparative studies of NP4 and NP2 at close to physiological pH.

    Science.gov (United States)

    Berry, Robert E; Muthu, Dhanasekaran; Yang, Fei; Walker, F Ann

    2015-01-20

    The β-barrel nitrophorin (NP) heme proteins are found in the saliva of the blood-sucking insect Rhodnius prolixus, which synthesizes and stores nitric oxide (NO) in the salivary glands. NO is bound to iron of the NPs and is released by dilution and an increase in pH when the insect spits its saliva into the tissues of a victim, to aid in obtaining a blood meal. In the adult insect, there are four nitrophorins, NP1-NP4, which have sequence similarities in two pairs, NP1 and NP4 (90% identical) and NP2 and NP3 (80% identical). The available crystal structures of NP4 have been used to propose that pH-dependent changes in the conformation of two loops between adjacent β-strands at the front opening of the protein, the A-B and G-H loops, determine the rate of NO release. At pH 7.3, NP4 releases NO 17 times faster than NP2 does. In this work, the aqua complexes of NP4 and NP2 have been investigated by nuclear magnetic resonance (NMR) relaxation measurements to probe the pico- to nanosecond and micro- to millisecond time scale motions at two pH values, 6.5 and 7.3. It is found that NP4-OH2 is fairly rigid and only residues in the loop regions show dynamics at pH 6.5; at pH 7.3, much more dynamics of the loops and most of the β-strands are observed while the α-helices remain fairly rigid. In comparison, NP2-OH2 shows much less dynamics, albeit somewhat more than that of the previously reported NP2-NO complex [Muthu, D., Berry, R. E., Zhang, H., and Walker, F. A. (2013) Biochemistry 52, 7910-7925]. The reasons for this major difference between NP4 and NP2 are discussed.

  12. Cathepsin L of Triatoma brasiliensis (Reduviidae, Triatominae): sequence characterization, expression pattern and zymography.

    Science.gov (United States)

    Waniek, Peter J; Pacheco Costa, Juliana E; Jansen, Ana M; Costa, Jane; Araújo, Catarina A C

    2012-01-01

    Triatoma brasiliensis is considered one of the main vectors of Chagas disease commonly found in semi-arid areas of northeastern Brazil. These insects use proteases, such as carboxypeptidase B, aminopeptidases and different cathepsins for blood digestion. In the present study, two genes encoding cathepsin L from the midgut of T. brasiliensis were identified and characterized. Mature T. brasiliensis cathepsin L-like proteinases (TBCATL-1, TBCATL-2) showed a high level of identity to the cathepsin L-like proteinases of other insects, with highest similarity to Rhodnius prolixus. Both cathepsin L transcripts were highly abundant in the posterior midgut region, the main region of the blood digestion. Determination of the pH in the whole intestine of unfed T. brasiliensis revealed alkaline conditions in the anterior midgut region (stomach) and acidic conditions in the posterior midgut region (small intestine). Gelatine in-gel zymography showed the activity of at least four distinct proteinases in the small intestine and the cysteine proteinase inhibitors transepoxysuccinyl-l-leucylamido-(4-guanidino)butane (E-64) and cathepsin B inhibitor and N-(l-3-trans-propylcarbamoyl-oxirane-2-carbonyl)-l-isoleucyl-l-proline (CA-074) were employed to characterize enzymatic activity. E-64 fully inhibited cysteine proteinase activity, whereas in the samples treated with CA-074 residual proteinase activity was detectable. Thus, proteolytic activity could at least partially be ascribed to cathepsin L. Western blot analysis using specific anti cathepsin L antibodies confirmed the presence of cathepsin L in the lumen of the small intestine of the insects. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Estudo sobre a epidemiologia da doença de Chagas no Ceará. V. Quirópteros infectados com Tripanosomo tipo cruzi

    Directory of Open Access Journals (Sweden)

    J.E. de Alencar

    1976-12-01

    Full Text Available Numa série de pesquisas sobre a epidemiologia da Doença de Chagas no Ceará, muitas espécies de mamíferos foram examinadas, dentre elas algumas espécies de quirópteros. Já antes, no Brasil, 15 espécies foram encontradas infectadas com tripanosomo tipo cruzi, dentre as 30 encontradas infectadas na América, de 1931 a 1964. Esses estudos se fizeram aproveitando o material do Censo Relativo de Morcegos na área da Serra de Maranguape (realizado por dois autores, abrangendo os municípios de Maranguape e Caucaia. Em 141 exemplares (18 espécies e 5 famílias foram feitos xenos com 5 ninfas de Rhodnius prolixus. Examinando o material 30 a 45 dias depois, foram encontrados infectados 9 exemplares, todos da família Phyllostomidae: 7 Artibeus jamaicensis, 1 Glossophaga soricina e 1 Trachops cirrhosus. O primeiro já havia sido encontrado infectado na Colombia e no Panamá; o segundo o foi na Colombia e no Brasil (Estado do Pará; o terceiro o é pela primeira vez. As duas primeiras espécies são insetívoras e frugívoras; a terceira é carnívora, além de frugívora e insetívora. Os parasitos isolados apresentaram características morfológicas e de cultura que permitem colocá-los no grupo dos tripanosomos tipo cruzi.' infectaram triatomíneos e produziram parasitemia (baixa e lesões típicas em camundongos brancos. A cepa de T. cirrhosus não foi isolada, mas as formas metacíclicas em triatomíneos eram semelhantes.

  14. Characterization of burdock mottle virus, a novel member of the genus Benyvirus, and the identification of benyvirus-related sequences in the plant and insect genomes.

    Science.gov (United States)

    Kondo, Hideki; Hirano, Shuichi; Chiba, Sotaro; Andika, Ida Bagus; Hirai, Makoto; Maeda, Takanori; Tamada, Tetsuo

    2013-10-01

    The complete nucleotide sequence of the burdock mottle virus (BdMoV) isolated from an edible burdock plant (Arctium lappa) in Japan has been determined. BdMoV has a bipartite genome, whose organization is similar to RNA1 and RNA2 of benyviruses, beet necrotic yellow vein virus (BNYVV), beet soil-borne mosaic virus (BSBMV), and rice stripe necrosis virus (RSNV). BdMoV RNA1 (7038 nt) contains a single open reading frame (ORF) encoding a 249-kDa polypeptide that consists of methyl-transferase, helicase, papain-like protease, AlkB-like, and RNA-dependent RNA polymerase domains. The AlkB-like domain sequence is not present in the proteins encoded by other known benyviruses, but is found in replication-associated proteins of viruses mainly belonging to the families Alfaflexiviridae and Betaflexiviridae. BdMoV RNA2 (4315 nt) contains six ORFs that are similar to those of benyviruses: these are coat protein (CP), CP readthrough, triple gene block movement and cysteine-rich proteins. Phylogenetic analyses showed that BdMoV is more closely related to BNYVV and BSBMV than to RSNV. Database searches showed that benyvirus replicase-related sequences are present in the chromosomes of a chickpea plant (Cicer arietinum) and a blood-sucking insect (Rhodnius prolixus). Some other benyvirus-related sequences are found in the transcriptome shotgun libraries of a few species of plants and a bark beetle. Our results show that BdMoV is a distinct species of the genus Benyvirus and that ancestral and extant benyviruses may have infected or currently infect a wide range of hosts, including plants and insects. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. [Possible oral transmission of Chagas disease among hydrocarbons sector workers in Casanare, Colombia, 2014].

    Science.gov (United States)

    Zuleta-Dueñas, Liliana Patricia; López-Quiroga, Ángela Johana; Torres-Torres, Fernando; Castañeda-Porras, Oneida

    2017-06-01

    Trypanosoma cruzi, the etiological agent for Chagas disease, can be transmitted by oral intake of contaminated food or drinks. During epidemiological week 14 of 2014, two cases of acute Chagas disease were notified among hydrocarbons sector workers in Paz de Ariporo, Casanare. To characterize the affected population, to establish control and prevention measures and to confirm the outbreak. We conducted an outbreak investigation that included the following components: a) Search for symptomatic people compatible with Chagas disease according to the case definition for their referral to medical services; b) entomological survey (192/197 houses); c) sanitary inspection and microbiological analysis of food samples; and d) study of reservoirs. Data management and analysis were done with Epi-Info 7.1.5 using descriptive statistics. We also calculated intradomicile and peridomicile triatomine infestation indexes. We detected 552 exposed people; 40 had the disease (7.2%), of whom seven were women (17,5%) and 33, men (82.5%), i.e., a male-female ratio of 5:1. The mean age was 39.1 ± 10.8 years; the attack rate was 7.2% and lethality, 5% (2/40). Symptoms included fever (100% of cases), headache (80%), myalgia and arthralgia (65%), facial edema (55%), and abdominal pain (37.5%). The mean incubation time was 17 days (range: 3-21). Rhodnius prolixus domiciliary infestation index was 3.3 % and 2.2% in the peridomicile. In the five restaurants inspected sanitary conditions were deficient and food samples were microbiologically non-conforming. We found a dog and two opossums positive for IgG antibodies by ELISA. Environmental, sanitary and epidemiological conditions at the place confirmed an outbreak of Chagas diseases related to occupational exposure, possibly by oral transmission, which may be the largest to date in Colombia.

  16. Automated segmentation of synchrotron radiation micro-computed tomography biomedical images using Graph Cuts and neural networks

    International Nuclear Information System (INIS)

    Alvarenga de Moura Meneses, Anderson; Giusti, Alessandro; Pereira de Almeida, André; Parreira Nogueira, Liebert; Braz, Delson; Cely Barroso, Regina; Almeida, Carlos Eduardo de

    2011-01-01

    Synchrotron Radiation (SR) X-ray micro-Computed Tomography (μCT) enables magnified images to be used as a non-invasive and non-destructive technique with a high space resolution for the qualitative and quantitative analyses of biomedical samples. The research on applications of segmentation algorithms to SR-μCT is an open problem, due to the interesting and well-known characteristics of SR images for visualization, such as the high resolution and the phase contrast effect. In this article, we describe and assess the application of the Energy Minimization via Graph Cuts (EMvGC) algorithm for the segmentation of SR-μCT biomedical images acquired at the Synchrotron Radiation for MEdical Physics (SYRMEP) beam line at the Elettra Laboratory (Trieste, Italy). We also propose a method using EMvGC with Artificial Neural Networks (EMANNs) for correcting misclassifications due to intensity variation of phase contrast, which are important effects and sometimes indispensable in certain biomedical applications, although they impair the segmentation provided by conventional techniques. Results demonstrate considerable success in the segmentation of SR-μCT biomedical images, with average Dice Similarity Coefficient 99.88% for bony tissue in Wistar Rats rib samples (EMvGC), as well as 98.95% and 98.02% for scans of Rhodnius prolixus insect samples (Chagas's disease vector) with EMANNs, in relation to manual segmentation. The techniques EMvGC and EMANNs cope with the task of performing segmentation in images with the intensity variation due to phase contrast effects, presenting a superior performance in comparison to conventional segmentation techniques based on thresholding and linear/nonlinear image filtering, which is also discussed in the present article.

  17. Infestación por triatominos en comunidades indígenas de Valledupar, Colombia Infestação por barbeiros em comunidades indígenas de Valledupar, Colômbia Infestation by triatomine bugs in indigenous communities of Valledupar, Colombia

    Directory of Open Access Journals (Sweden)

    Marleny Montilla

    2011-08-01

    Full Text Available OBJETIVO: Calcular los índices infestación por triatominos en comunidades indígenas en Colombia. MÉTODOS: Se realizó estudio descriptivo en 19 comunidades indígenas del municipio de Valledupar Departamento de Cesar, Colombia. Durante junio a diciembre de 2007 se recolectaron triatominos por búsqueda activa en las viviendas de los indígenas. Los insectos luego fueron identificados por las claves de Lent & Wygodzinsky. Se desarrolló estudio del proceso infectivo en modelo animal y análisis enzimático de cepas de Trypanosoma cruzi, detectadas en heces de triatominos. RESULTADOS: Rhodnius prolixus presentó índice de densidad en las viviendas de 154,7%, Triatoma dimidiata de 102,45%, Triatoma maculata de 109,25% y Panstrogylus geniculatus de 0,3%. El índice promedio de infestación de las cuatro especies fue de 40,54% y, el de infección con T. cruzi de 9,4%. De cinco hemocultivos positivos para T. cruzi, tres se caracterizaron por isoenzimas, clasificándose en T. cruzi grupo I. El estudio de las biopsias reveló pocas características patológicas durante el proceso de infección con las cepas de T. cruzi aisladas de triatominos domiciliados. CONCLUSIÓN: Los altos índices de infestación por triatominos en las viviendas y el índice de infección por T. cruzi, evidencian la transmisión activa de la enfermedad de Chagas, situación que amerita la aplicación de medidas de control vectorial y el estudio seroepidemilógico de la población en riesgo. La identificación de las cepas de T. cruzi como grupo I concuerda con otros estudios realizados en esta región colombiana.OBJETIVO: Calcular índices de infestação por barbeiros em comunidades indígenas da Colômbia. MÉTODOS: Estudo descritivo em 19 comunidades do município de Valledupar, departamento de Cesar, Colômbia. A coleta de barbeiros foi realizada por busca ativa nas casas dos indígenas de junho e dezembro de 2007. A identificação taxonômica foi feita conforme Lent

  18. The Afrotropical Miomantis caffra Saussure 1871 and M. paykullii Stal 1871: first records of alien mantid species in Portugal and Europe, with an updated checklist of Mantodea in Portugal (Insecta: Mantodea

    Directory of Open Access Journals (Sweden)

    Eduardo Marabuto

    2014-11-01

    In the absence of recent revisionary work on the Mantodea of Portugal and given the need to provide an accessible identification tool, both a checklist and a key to species are provided for all species in the country.

  19. Příběh fyzika Lavrentěva – muže, který zůstal věrný své myšlence

    Czech Academy of Sciences Publication Activity Database

    Řípa, Milan

    2012-01-01

    Roč. 15, č. 6 (2012), s. 22-25 ISSN 1212-1673 Institutional research plan: CEZ:AV0Z20430508 Keywords : fusion * tokamak * Charkov * inertial electrostatic confinement * electromagnetic trap * Sacharov * Berija Subject RIV: BL - Plasma and Gas Discharge Physic s

  20. Differences in morphometrics and reproductive physiology between two populations of Trissolcus japonicus, a promising biological control agent candidate for brown marmorated stink bug (Halyomorpha halys Stal) in the US

    Science.gov (United States)

    Trissolcus japonicus (Ashmead), a solitary egg parasitoid of Pentatomidae native to Southeast Asia, has been undergoing host-range testing in U.S. quarantine facilities since 2009 as a candidate for the biological control of brown marmorated stink bug (Halyomorpha halys Stål)(BMSB), an invasive agri...

  1. Nitrided steel 38CrN3MAFA for supporting elements in nuclear power plants; Vysokoazotistaya stal` tipa 38HN3MAFA dlya krepezhnikh detajlej reaktorov AEhS

    Energy Technology Data Exchange (ETDEWEB)

    Rasheva, I; Argirov, Kh; Stojchev, T [Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. po Metaloznanie i Tekhnologiya na Metalite

    1996-12-31

    Nitride doping of steel at different concentrations is achieved by counter-pressure casting in nitrogen ambience. A new type of steel is developed containing 0.05-0.2% N{sub 2}. It is compared to a standard 34NiCrMoV145 steel (DIN). The mechanical properties are improved significantly after a two-stage thermal treatment and are as follows: fluidity limit R{sub 0}.2>=1045 MPa, relative elongation A>=15%, relative shortening Z>=62%, impact viscosity KCU >= 1 MJ/m{sup 2}. The quench hardening consists of heating to 800-850{sup o} C in oil and cooling to 600{sup o} C in air. The steel is suitable for rotors, turbines, compressor shafts and reactor supporting elements in nuclear power plants. 3 refs., 6 figs., 6 tabs.

  2. An Investigation on the Ecology of Triatoma vitticeps (Stal, 1859 and its Possible Role in the Transmission of Trypanosoma cruzi, in the Locality of Triunfo, Santa Maria Madalena Municipal District, State of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Gonçalves Teresa Cristina M

    1998-01-01

    Full Text Available From January 1989 to April 1995, 465 specimens of Triatoma vitticeps were collected in the locality of Triunfo, 2nd District of Santa Maria Madalena municipal district, State of Rio de Janeiro. The bugs were found indoors by local residents with predominance of adults. The flight activity was high in hot months when the incidence in the domicile also increased. Two hundred and two bugs (111 alive and 91 dead were examined for Trypanosoma cruzi infection. This was detected in 31 of the dead bugs (34% and 88 (79% of the live bugs examined. With a view to investigate the possible vertebrate hosts of the T. cruzi isolates, the blood of 122 mammals was examined through Giemsa-stained smears, hemocultures and xenodiagnosis. T. cruzi was detected in three specimens of Didelphis marsupialis and T. (M. theileri was detected in one specimen of Bos taurus. The parasites were isolated from triatomine feces, xenoculture and hemoculture. No evidence of human infection was detected in 58 inhabitants examined, as evaluated by indirect imunofluorescence technique using T. cruzi epimastigotes as antigens. These results show that T. vitticeps is still a sylvatic species although nymphs have been found inside the domicile. Thus, an epidemiological vigilance is necessary to know the behaviour of this species following the continuous modifications promoted by the presence of man.

  3. Dimerization of nitrophorin 4 at low pH and comparison to the K1A mutant of nitrophorin 1.

    Science.gov (United States)

    Berry, Robert E; Yang, Fei; Shokhireva, Tatiana K; Amoia, Angela M; Garrett, Sarah A; Goren, Allena M; Korte, Stephanie R; Zhang, Hongjun; Weichsel, Andrzej; Montfort, William R; Walker, F Ann

    2015-01-20

    Nitrophorin 4, one of the four NO-carrying heme proteins from the salivary glands of Rhodnius prolixus, forms a homodimer at pH 5.0 with a Kd of ∼8 μM. This dimer begins to dissociate at pH 5.5 and is completely dissociated to monomer at pH 7.3, even at 3.7 mM. The dimer is significantly stabilized by binding NO to the heme and at pH 7.3 would require dilution to well below 0.2 mM to completely dissociate the NP4-NO homodimer. The primary techniques used for investigating the homodimer and the monomer-dimer equilibrium were size-exclusion fast protein liquid chromatography at pH 5.0 and (1)H{(15)N} heteronuclear single-quantum coherence spectroscopy as a function of pH and concentration. Preparation of site-directed mutants of NP4 (A1K, D30A, D30N, V36A/D129A/L130A, K38A, R39A, K125A, K125E, D132A, L133V, and K38Q/R39Q/K125Q) showed that the N-terminus, D30, D129, D132, at least one heme propionate, and, by association, likely also E32 and D35 are involved in the dimerization. The "closed loop" form of the A-B and G-H flexible loops of monomeric NP4, which predominates in crystal structures of the monomeric protein reported at pH 5.6 but not at pH 7.5 and which involves all of the residues listed above except D132, is required for dimer formation. Wild-type NP1 does not form a homodimer, but NP1(K1A) and native N-terminal NP1 form dimers in the presence of NO. The homodimer of NP1, however, is considerably less stable than that of NP4 in the absence of NO. This suggests that additional aspartate or glutamate residues present in the C-terminal region of NP4, but not NP1, are also involved in stabilizing the dimer.

  4. Hallazgo de Trypanosoma Cruzi en momias de más de 4000 años de antigüedad

    Directory of Open Access Journals (Sweden)

    Carlos Jaramillo

    2000-08-01

    Full Text Available

    Se presentan los antecedentes de la presencia de triatominos domiciliados en Colombia desde la primera publicación hecha por el doctor César Uribe en 1929 (Editorial Minerva, Bogotá donde se consigna el hallazgo de Trypanosoma cruzi y Trypanosoma rangeli en 15 ejemplares de Rhodnius prolixus provenientes de Prado, Tolima. A continuación se analizan las demás publicaciones en orden cronológico. Informe del Profesor Emile Brumpt (Revista de Higiene, año XX – Números 11 y 12, 1939, Distribución de los Triatominos en Colombia, Hernando Ucrós, Hernando Rocha, Marcos Duque (Antioquia Médica Vol. 21 – 1971 No. 8; Distribution of Triatomine – transmitted trypanosomamiasis in Colombia and vew records of the bugs and infections. A. D’Alessandro, Pablo Barreto and C. A. Duarte R. (1972, J. Med. Ent. Vol. 8, No. 2: 159-172; Colombian Triatominae and their infestation with Trypanosomatid Flagellates. Marinkelle Cornelis J. (1972 Mitt Inst. – Aleman Invest. Cient. 6:13-29; Nuevos registros de triatominos domiciliarios y extradomiciliarios en Colombia. Antonio D’Alessandro, Pablo Barreto y Mauricio Thomas. Colombia Médica Vol. 12 No. 2 – 1981.

    Basándose en la anterior información se llega a la conclusión de que los Triatominae domiciliados en Colombia se encuentran en poblaciones situadas sobre los 2.000msnm, principalmente en las zonas central y oriental del país.

    El Instituto Nacional de Salud en el año de 1990, como una primera etapa para tratar de determinar la magnitud del problema de la tripanosomiasis americana en Colombia, realizó una investigación para establecer la verdadera distribución de los triatominos domiciliarios en el país.

    El estudio se hizo usando el sistema de muestreo, en una muestra estadísticamente representativa. Se inspeccionaron las viviendas de las zonas rurales; se capturaron triatominos vectores que, posteriormente, fueron examinados sistemáticamente en búsqueda de

  5. Distribución de Triatomíneos domiciliados en Colombia.

    Directory of Open Access Journals (Sweden)

    Augusto Corredor Arjona

    2000-08-01

    Full Text Available

    Se presentan los antecedentes de la presencia de triatominos domiciliados en Colombia desde la primera publicación hecha por el doctor César Uribe en 1929 (Editorial Minerva, Bogotá donde se consigna el hallazgo de Trypanosoma cruzi y Trypanosoma rangeli en 15 ejemplares de Rhodnius prolixus provenientes de Prado, Tolima. A continuación se analizan las demás publicaciones en orden cronológico. Informe del Profesor Emile Brumpt (Revista de Higiene, año XX – Números 11 y 12, 1939, Distribución de los Triatominos en Colombia, Hernando Ucrós, Hernando Rocha, Marcos Duque (Antioquia Médica Vol. 21 – 1971 No. 8; Distribution of Triatomine – transmitted trypanosomamiasis in Colombia and vew records of the bugs and infections. A. D’Alessandro, Pablo Barreto and C. A. Duarte R. (1972, J. Med. Ent. Vol. 8, No. 2: 159-172; Colombian Triatominae and their infestation with Trypanosomatid Flagellates. Marinkelle Cornelis J. (1972 Mitt Inst. – Aleman Invest. Cient. 6:13-29; Nuevos registros de triatominos domiciliarios y extradomiciliarios en Colombia. Antonio D’Alessandro, Pablo Barreto y Mauricio Thomas. Colombia Médica Vol. 12 No. 2 – 1981.

    Basándose en la anterior información se llega a la conclusión de que los Triatominae domiciliados en Colombia se encuentran en poblaciones situadas sobre los 2.000msnm, principalmente en las zonas central y oriental del país.

    El Instituto Nacional de Salud en el año de 1990, como una primera etapa para tratar de determinar la magnitud del problema de la tripanosomiasis americana en Colombia, realizó una investigación para establecer la verdadera distribución de los triatominos domiciliarios en el país.

    El estudio se hizo usando el sistema de muestreo, en una muestra estadísticamente representativa. Se inspeccionaron las viviendas de las zonas rurales; se capturaron triatominos vectores que, posteriormente, fueron examinados sistemáticamente en búsqueda de

  6. Comparación de métodos para la captura de triatominos (Hemiptera: Reduviidae en palmas Attalea butyracea en los Llanos Orientales de Colombia

    Directory of Open Access Journals (Sweden)

    Víctor Manuel Angulo

    2013-12-01

    Full Text Available Introducción. El estudio de los triatominos en sus ecótopos naturales tiene gran significado en la epidemiología de la enfermedad de Chagas. La recolección de insectos vivos y su establecimiento en insectarios permite realizar incontables estudios. Por ello se necesitan métodos efectivos para la captura de triatominos silvestres, especialmente especies intrusas como Rhodnius prolixus. Objetivo. Comparar cuatro métodos para la captura de triatominos en palmas para medir su efectividad. Materiales y métodos. El estudio se llevó a cabo en la localidad de Maní, departamento de Casanare, Colombia, con predominio de Attalea butyracea. Se compararon cuatro metodologías en 67 palmas: trampas con cebo vivo, búsqueda directa en palmas, tala y disección. Resultados. Los métodos fueron efectivos para recolectar ejemplares juveniles y adultos. La tala y la búsqueda manual mostraron los mayores índices de infestación (100 % y 83,33 %. La trampa Angulo mostró mayores índices de hacinamiento (4,93, densidad (3,76, rango de abundancia (1-13 e índice adulto/ninfa (0,22. La tala y la disección fue el método que significativamente recolectó más triatominos en comparación con los otros (p0,05. Conclusiones. Aunque la tala fue el mejor método para la recolección del mayor número de triatominos, los métodos con el cebo vivo con adhesivos o refugios para atrapar los insectos, fueron una buena alternativa. Entre ellos, la trampa Angulo mostró mejores resultados y evitó la exposición del investigador al riesgo y la intervención de ecotopos naturales.   doi: http://dx.doi.org/10.7705/biomedica.v33i4.835

  7. Decoding the anti-Trypanosoma cruzi action of HIV peptidase inhibitors using epimastigotes as a model.

    Directory of Open Access Journals (Sweden)

    Leandro S Sangenito

    Full Text Available BACKGROUND: Aspartic peptidase inhibitors have shown antimicrobial action against distinct microorganisms. Due to an increase in the occurrence of Chagas' disease/AIDS co-infection, we decided to explore the effects of HIV aspartic peptidase inhibitors (HIV-PIs on Trypanosoma cruzi, the etiologic agent of Chagas' disease. METHODOLOGY AND PRINCIPAL FINDINGS: HIV-PIs presented an anti-proliferative action on epimastigotes of T. cruzi clone Dm28c, with IC50 values ranging from 0.6 to 14 µM. The most effective inhibitors, ritonavir, lopinavir and nelfinavir, also had an anti-proliferative effect against different phylogenetic T. cruzi strains. The HIV-PIs induced some morphological alterations in clone Dm28c epimastigotes, as reduced cell size and swollen of the cellular body. Transmission electron microscopy revealed that the flagellar membrane, mitochondrion and reservosomes are the main targets of HIV-PIs in T. cruzi epimastigotes. Curiously, an increase in the epimastigote-into-trypomastigote differentiation process of clone Dm28c was observed, with many of these parasites presenting morphological alterations including the detachment of flagellum from the cell body. The pre-treatment with the most effective HIV-PIs drastically reduced the interaction process between epimastigotes and the invertebrate vector Rhodnius prolixus. It was also noted that HIV-PIs induced an increase in the expression of gp63-like and calpain-related molecules, and decreased the cruzipain expression in epimastigotes as judged by flow cytometry and immunoblotting assays. The hydrolysis of a cathepsin D fluorogenic substrate was inhibited by all HIV-PIs in a dose-dependent manner, showing that the aspartic peptidase could be a possible target to these drugs. Additionally, we verified that ritonavir, lopinavir and nelfinavir reduced drastically the viability of clone Dm28c trypomastigotes, causing many morphological damages. CONCLUSIONS AND SIGNIFICANCE: The results

  8. Disintegrins from Hematophagous Sources

    Directory of Open Access Journals (Sweden)

    Ivo M. B. Francischetti

    2012-04-01

    Full Text Available Bloodsucking arthropods are a rich source of salivary molecules (sialogenins which inhibit platelet aggregation, neutrophil function and angiogenesis. Here we review the literature on salivary disintegrins and their targets. Disintegrins were first discovered in snake venoms, and were instrumental in our understanding of integrin function and also for the development of anti-thrombotic drugs. In hematophagous animals, most disintegrins described so far have been discovered in the salivary gland of ticks and leeches. A limited number have also been found in hookworms and horseflies, and none identified in mosquitoes or sand flies. The vast majority of salivary disintegrins reported display a RGD motif and were described as platelet aggregation inhibitors, and few others as negative modulator of neutrophil or endothelial cell functions. This notably low number of reported disintegrins is certainly an underestimation of the actual complexity of this family of proteins in hematophagous secretions. Therefore an algorithm was created in order to identify the tripeptide motifs RGD, KGD, VGD, MLD, KTS, RTS, WGD, or RED (flanked by cysteines in sialogenins deposited in GenBank database. The search included sequences from various blood-sucking animals such as ticks (e.g., Ixodes sp., Argas sp., Rhipicephalus sp., Amblyomma sp., tabanids (e.g., Tabanus sp., bugs (e.g., Triatoma sp., Rhodnius prolixus, mosquitoes (e.g., Anopheles sp., Aedes sp., Culex sp., sand flies (e.g., Lutzomyia sp., Phlebotomus sp., leeches (e.g., Macrobdella sp., Placobdella sp. and worms (e.g., Ancylostoma sp.. This approach allowed the identification of a remarkably high number of novel putative sialogenins with tripeptide motifs typical of disintegrins (>450 sequences whose biological activity remains to be verified. This database is accessible

  9. Infestación por triatominos en comunidades indígenas de Valledupar, Colombia

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    Marleny Montilla

    2011-08-01

    Full Text Available OBJETIVO: Calcular los índices infestación por triatominos en comunidades indígenas en Colombia. MÉTODOS: Se realizó estudio descriptivo en 19 comunidades indígenas del municipio de Valledupar Departamento de Cesar, Colombia. Durante junio a diciembre de 2007 se recolectaron triatominos por búsqueda activa en las viviendas de los indígenas. Los insectos luego fueron identificados por las claves de Lent & Wygodzinsky. Se desarrolló estudio del proceso infectivo en modelo animal y análisis enzimático de cepas de Trypanosoma cruzi, detectadas en heces de triatominos. RESULTADOS: Rhodnius prolixus presentó índice de densidad en las viviendas de 154,7%, Triatoma dimidiata de 102,45%, Triatoma maculata de 109,25% y Panstrogylus geniculatus de 0,3%. El índice promedio de infestación de las cuatro especies fue de 40,54% y, el de infección con T. cruzi de 9,4%. De cinco hemocultivos positivos para T. cruzi, tres se caracterizaron por isoenzimas, clasificándose en T. cruzi grupo I. El estudio de las biopsias reveló pocas características patológicas durante el proceso de infección con las cepas de T. cruzi aisladas de triatominos domiciliados. CONCLUSIÓN: Los altos índices de infestación por triatominos en las viviendas y el índice de infección por T. cruzi, evidencian la transmisión activa de la enfermedad de Chagas, situación que amerita la aplicación de medidas de control vectorial y el estudio seroepidemilógico de la población en riesgo. La identificación de las cepas de T. cruzi como grupo I concuerda con otros estudios realizados en esta región colombiana.

  10. Prevalencia de patologías tropicales y factores de riesgo en la comunidad indígena de bunkwimake, sierra nevada de Santa Marta

    Directory of Open Access Journals (Sweden)

    Juan C. Dib

    2013-10-01

    Full Text Available Las enfermedades tropicales son endémicas en la Sierra Nevada de Santa Marta, sin embargo se carece de información acerca de la distribución de estas enfermedades en las comunidades indígenas que la habitan. Mediante estudios entomológicos y seroepidemiológicos, se estudiaron los factores de riesgo y la prevalencia de enfermedad de Chagas, leishmaniosis, hepatitis B y parasitosis intestinales en la comunidad indígena de Bunkwimake, ubicada en la vertiente norte de la Sierra Nevada. Los resultados de los estudios serológicos en 94 individuos reportaron una positividad de 18 (19%, 52(55% y 19(20% para infección por Tripanosoma cruzi, leishmania y el virus de la hepatitis B respectivamente. Adicionalmente, en 41(74% de 56 niños indígenas se encontró la presencia de parasitosis intestinales al examen coprológico. En los estudios entomológicos se captu-raron 37 triatominos en 16 viviendas distribuidos de la siguiente manera: 13 Triatoma dimidiata, 12 Rhodnius prolixus y 12 Pastrongylus geniculatus. Las tres especies se encontraron colonizando las viviendas indígenas y presentaron infeccilón para Trypanosoma cruzi. Dos especies de flebotominos fueron capturados en las vivien-das: 5 lutzomyia Gomezi y 7 Lutzomyia hirsute hirsute. El presente estudio demostró una importante prevalencia de infección por T. Cruzi y Leishmania en la población infantil, indicando transmisión reciente de ambas infec-ciones. Adicionalmente, los estudios entomológicos indican que existe un riesgo de transmisión doméstica de T. Cruzi y Leishmania por especies selváticas de triatominos y flebotominos. Se necesitan estudios adicionales que determinen la ecoepidemiología y dinámicas de trasnmisión de la Leishmanisosis y la enfermedad de Chagas en esta población para diseñar estrategias de control más adecuadas. Debido a que los programas verticales de fumigación y mejoramiento de vivienda en las comunidades indígenas no son viables, nuevas

  11. Ecological and biogeographical observations on Cerambycidae (Coleoptera) from California, USA

    OpenAIRE

    Swift, Ian

    2009-01-01

    New ecological and biogeographical observations are presented for the following 32 species of Cerambycidae from California: Atimia confusa dorsalis LeConte, Anelaphus albofasciatus (Linell), Aneflus prolixus prolixus LeConte, Anoplocurius incompletus Linsley, Brothylus conspersus LeConte, Callidiellum virescens Chemsak and Linsley, Calloides lorquini (Buquet), Clytus chemsaki Hovore and Giesbert, Enaphalodes hispicornis (Linnaeus), Methia brevis Fall, Neaneflus fuchsi (Wickham), Neoclytus bal...

  12. Journal of the Cameroon Academy of Sciences - Vol 2, No 1 (2002)

    African Journals Online (AJOL)

    Observations on the Meiotic Process in the African Pest Grasshopper Taphronota thaelephora Stal. (Orthoptera : Pyrgomorphidae), EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. RA Seino, DA Focho, FA Njukeng, 3-6 ...

  13. 'Welzijnsvloer verdient zich op den duur terug'; van den Berg beproeft de groene vlag roostervloer

    NARCIS (Netherlands)

    Anoniem,

    2010-01-01

    Het onderzoek van Wageningen UR naar de welzijnsvloeren is nog in volle gang. Maar vleeskalverhouder Wijnand van den Berg uit Kootwijkerbroek heeft op eigen initiatief al een welzijnsrooster in zijn stal op proef

  14. Interrupting Chagas disease transmission in Venezuela A interrupção da transmissão da doença de Chagas na Venezuela

    Directory of Open Access Journals (Sweden)

    Alberto ACHÉ

    2001-02-01

    Full Text Available The interruption of vectorial transmission of Chagas disease in Venezuela is attributed to the combined effects of ongoing entomoepidemiological surveillance, ongoing house spraying with residual insecticides and the concurrent building and modification of rural houses in endemic areas during almost five decades. The original endemic areas which totaled 750,000 km², have been reduced to 365,000 km². During 1958-1968, initial entomological evaluations carried out showed that the house infestation index ranged between 60-80%, the house infection index at 8-11% and a house density index of 30-50 triatomine bugs per house. By 1990-98, these indexes were further reduced to 1.6-4.0%, 0.01-0.6% and 3-4 bugs per house respectively. The overall rural population seroprevalence has declined from 44.5% (95% C.I.: 43.4-45.3% to 9.2% (95% C.I.: 9.0-9.4% for successive grouped periods from 1958 to 1998. The annual blood donor prevalence is firmly established below 1%. The population at risk of infection has been estimated to be less than four million. Given that prevalence rates are stable and appropriate for public health programmes, consideration has been given to potential biases that may distort results such as: a geographical differences in illness or longevity of patients; b variations in levels of ascertainment; c variations in diagnostic criteria; and d variations in population structure, mainly due to appreciable population migration. The endemic areas with continuous transmission are now mainly confined to piedmonts, as well as patchy foci in higher mountainous ranges, where the exclusive vector is Rhodnius prolixus. There is also an unstable area, of which landscapes are made up of grasslands with scattered broad-leaved evergreen trees and costal plains, where transmission is very low and occasional outbreaks are reported.A interrupção da transmissão da doença de Chagas é atribuida aos efeitos conjuntos da vigilância soroepidemiol

  15. Evaluación de la actividad tóxica de los insecticidas piretroides deltametrina y lambdacihalotrina en dos poblaciones de campo de Rhodnius pallescens (Hemíptera: Reduviidae de Panamá

    Directory of Open Access Journals (Sweden)

    Lorenzo Cáceres

    2011-04-01

    Conclusiones. En ninfas de estadios I y V de ambas poblaciones de R. pallescens, se observó mediante los valores obtenidos de factor de resistencia que no existen ninguna diferencia significativa en el efecto tóxico de los insecticidas estudiados. Esto permite establecer que las dos cepas de R. pallescens son sensibles a los insecticidas deltametrina y lambdacihalotrina.

  16. Příběh vzácného motýla, který se stal na Šumavě obyčejným aneb co k životu potřebuje perleťovec mokřadní

    Czech Academy of Sciences Publication Activity Database

    Slámová, Irena; Vrba, Pavel; Konvička, Martin

    2012-01-01

    Roč. 2012, - (2012), s. 16-17 ISSN 0862-5166 R&D Projects: GA ČR GAP505/10/2248; GA ČR GAP505/10/2167; GA MŠk LC06073 Grant - others:Grantová agentura Jihočeské univerzity(CZ) GA JU 135/2010/P; Grantová agentura Jihočeské univerzity(CZ) 144/2010/P Institutional support: RVO:60077344 Keywords : Proclossiana eunomia

  17. Historia de la Tripanosomiasis Americana en Colombia

    Directory of Open Access Journals (Sweden)

    Fernando Serpa Florez

    2000-08-01

    cruzi fueron realizados por César Uribe Piedrahita en 1929. Encontró vectores del mal infectados con estos flagelados en Prado (Tolima como lo públicó en su trascendental comunicación “Infección de Rhodnius prolixus Stahl por Trypanosoma cruzi y Trypanosoma rangeli”, en la Revista Médico-Quirúrgica de los Hospitales de Bogotá, de dicho año (3...

  18. Miocardite no macaco Cebus após inoculações repetidas com Schizotrypanum cruzi

    Directory of Open Access Journals (Sweden)

    C. Magarinos Torres

    1958-07-01

    Full Text Available Transmission of Chagas disease is realized through contamination of ocular conjunctiva, mucosa or skin with infected dejections eliminated by the insect vectors of Schizotrypanum cruzi (Triatoma infestans, Panstrongylus megistus and Rhodnius prolixus. The triatomid bugs live in holes and craks in the walls, in beds, behind trunks, etc. Found in primitive mud huts covered with thatched roofs, and so the human dwellers have many chances to contract the disease, reinfections being reasonably more to expect than a single inoculation. Experimental work reproducing those natural conditions is welcomed as some important features in the pathologic picture of the disease such as the extensive myocardial fibrosis seen in chronic cases are still incompletely known. Microscopic changes were studied in the heart muscle of seven Cebus monkeys infected by S. cruzi. This animal survives the acute stage of the disease and so is particularly suited to experiments of long duration in which several inoculations of S. cruzi are performed. Three different strains of S. cruzi isolated from acute cases of Chagas' disease were employed. One monkey was injected in the skin with infected blood and necropsied after 252 days. Two monkeys were three times, and one, eight times infected in skin, one of them with contaminated blood, and two with contaminated blood and dejections from infected bugs. The necropsies were performed after 35, 95 and 149 days. One monkey was three times inoculated through the intact ocular conjunctiva (one time with infected blood, two times with dejections from infected bugs, and one time through the wounded buccal mucosa, and necropsied after 134 days. Another monkey was six times inoculated, four times through the intact ocular conjunctiva (one time with contaminated blood, three times with dejections from infected bugs and two times injected in the skin with infected blood, and necropsied after 157 days. Finally, another monkey was nine times

  19. The impact of Chagas disease control in Latin America: a review.

    Science.gov (United States)

    Dias, J C P; Silveira, A C; Schofield, C J

    2002-07-01

    Discovered in 1909, Chagas disease was progressively shown to be widespread throughout Latin America, affecting millions of rural people with a high impact on morbidity and mortality. With no vaccine or specific treatment available for large-scale public health interventions, the main control strategy relies on prevention of transmission, principally by eliminating the domestic insect vectors and control of transmission by blood transfusion. Vector control activities began in the 1940s, initially by means of housing improvement and then through insecticide spraying following successful field trials in Brazil (Bambui Research Centre), with similar results soon reproduced in São Paulo, Argentina, Venezuela and Chile. But national control programmes only began to be implemented after the 1970s, when technical questions were overcome and the scientific demonstration of the high social impact of Chagas disease was used to encourage political determination in favour of national campaigns (mainly in Brazil). Similarly, large-scale screening of infected blood donors in Latin America only began in the 1980s following the emergence of AIDS. By the end of the last century it became clear that continuous control in contiguous endemic areas could lead to the elimination of the most highly domestic vector populations - especially Triatoma infestans and Rhodnius prolixus - as well as substantial reductions of other widespread species such as T. brasiliensis, T. sordida, and T. dimidiata, leading in turn to interruption of disease transmission to rural people. The social impact of Chagas disease control can now be readily demonstrated by the disappearance of acute cases and of new infections in younger age groups, as well as progressive reductions of mortality and morbidity rates in controlled areas. In economic terms, the cost-benefit relationship between intervention (insecticide spraying, serology in blood banks) and the reduction of Chagas disease (in terms of medical and

  20. The impact of Chagas disease control in Latin America: a review

    Directory of Open Access Journals (Sweden)

    JCP Dias

    2002-07-01

    Full Text Available Discovered in 1909, Chagas disease was progressively shown to be widespread throughout Latin America, affecting millions of rural people with a high impact on morbidity and mortality. With no vaccine or specific treatment available for large-scale public health interventions, the main control strategy relies on prevention of transmission, principally by eliminating the domestic insect vectors and control of transmission by blood transfusion. Vector control activities began in the 1940s, initially by means of housing improvement and then through insecticide spraying following successful field trials in Brazil (Bambui Research Centre, with similar results soon reproduced in São Paulo, Argentina, Venezuela and Chile. But national control programmes only began to be implemented after the 1970s, when technical questions were overcome and the scientific demonstration of the high social impact of Chagas disease was used to encourage political determination in favour of national campaigns (mainly in Brazil. Similarly, large-scale screening of infected blood donors in Latin America only began in the 1980s following the emergence of AIDS. By the end of the last century it became clear that continuous control in contiguous endemic areas could lead to the elimination of the most highly domestic vector populations - especially Triatoma infestans and Rhodnius prolixus - as well as substantial reductions of other widespread species such as T. brasiliensis, T. sordida, and T. dimidiata, leading in turn to interruption of disease transmission to rural people. The social impact of Chagas disease control can now be readily demonstrated by the disappearance of acute cases and of new infections in younger age groups, as well as progressive reductions of mortality and morbidity rates in controlled areas. In economic terms, the cost-benefit relationship between intervention (insecticide spraying, serology in blood banks and the reduction of Chagas disease (in terms

  1. Presencia de Malameba locustae (Protozoa: Rhizopoda en acridios (Orthoptera: Acrididae de la provincia de Misiones, Argentina Presence of Malameba locustae (Protozoa: Rhizopoda in grasshoppers (Orthoptera: Acrididae of Misiones province, Argentina

    Directory of Open Access Journals (Sweden)

    Carlos E. Lange

    2004-07-01

    Full Text Available La ameba patógena Malameba locustae King y Taylor fue detectada parasitando ejemplares del acridio Ronderosia bergi (Stal recolectados en las cercanías del Parque Nacional Iguazú, Misiones. El hallazgo constituye el segundo registro de M. locustae para acridios sudamericanos.Individuals of the grasshopper Ronderosia bergi (Stal collected in the surroundings of Iguazú National Park, Misiones, were found to be parasitized by the pathogenic amoeba Malameba locustae King & Taylor. The finding constitutes the second record of M. locustae for southamerican grasshoppers.

  2. Arnold Rüütel - tshelovek goda!

    Index Scriptorium Estoniae

    2001-01-01

    Saar Polli küsitlusuuringu tulemusel pidas 35% vastanuist aasta inimeseks Arnold Rüütlit. Pealk. ajalehes Molodjozh Estonii (2001) 28. dets.: "Glavnõi tshelovek", lk. 2 ; pealk. ajalehes Narvskaja Gazeta (2001) 28. dets.: "Tshelovekom goda v Estonii stal novõi prezident stranõ", lk. 3 ; pealk. ajalehes Narvskaja Nedelja (2001) 29. dets.: "Titula tshelovek goda zhiteli Estonii udostoili Arnolda Rüütelja i ben Ladena", lk. 3 ; pealk. ajalehes Severnoje Poberezhje (2001) 28. dets.: "Tshelovekom goda stal novõi prezident", lk. 3. Arvamust avaldavad Tiit Sinissaar ja Villu Reiljan

  3. Reseña Histórica de algunos estudios Colombianos sobre Trypanosoma rangeli

    Directory of Open Access Journals (Sweden)

    Hernando Groot Liévano

    2000-08-01

    Full Text Available

    Parecerá extraño que uno de los primeros artículos de esta revista no se refiera a la enfermedad de Chagas. Tanto es así que cuando el doctor Felipe Guhl tuvo la idea de llamarme para esta presentación, mi primera respuesta fue negativa porque, obviamente debería hablarse del Trypanosoma cruzi y no del Trypanosoma rangeli. El presente artículo es un breve recuento de mi experiencia con este parásito y su importancia dado que coexiste con el T. cruzi y que, en ocasiones la diferenciación morfológica entre los dos no es tan clara cuando se examinan preparaciones de sangre en “gota gruesa” de vertebrados o preparaciones del contenido intestinal de los insectos vectores, y además porque tiene ciertas relaciones inmunológicas que es necesario tener en cuenta para evitar posibles confusiones. Por otra parte, su distribución geográfica es muy amplia extendiéndose desde México hasta el Perú y el Brasil.

    El Trypanosoma rangeli, llamado así por un distinguido médico y posteriormente diplomático de Venezuela, el doctor Enrique Tejera, quien encontró en los chipos, o sea en los Rhodnius prolixus de Venezuela, un pequeño flagelado muy largo, bastante diferente del Trypanosoma cruzi y resolvió ponerle el nombre de Trypanosoma o Crithidia rangeli pues no estaba muy seguro del género en el cual debía colocarlo. Evidentemente, sólo había visto la morfología de estos flagelados en el intestino de los Rhodnius y por consiguiente no tenía ningún otro elemento para identi-ficarlos.

    Únicamente comprobó que eran diferentes del cruzi. ¿Por qué le dedicó su descubrimiento a Rangel? Creo que es importante que nosotros los latinoamericanos conozcamos bien los valores científicos que han habido en nuestros países y en vez de preocuparnos por las artificiales fronteras políticas, lo cual en nada contribuye al progreso de la ciencia, comencemos a tener claro conocimiento de lo que en todas estas naciones hermanas por

  4. Environmental Compliance Assessment and Management Program

    Science.gov (United States)

    1994-04-01

    coa- stal waters between Makahuena Point and the westerly boundary of Hoai Bay 8. Niihau - All open coastal waters surrounding the island 9. All other...Beach (continued) 11 - 105 Table 11 - 16 (contaued) On Nihau: All wave-exposed reef communities On Lehua (off Niihau ): All wave-exposed reef communities

  5. Ventilatie en koeling in de zomerperiode

    NARCIS (Netherlands)

    Ellen, H.H.

    1997-01-01

    Na twee zomers met hoge buitentemperaturen over lange(re) periodes is er veel aandacht voor koelinstallaties in de vleeskuikensector. Deze installaties maken gebruik van het koelende effect van het verdampen van water door het water te vernevelen in de stal. In dit artikel wordt ingegaan op de

  6. ORF Alignment: NC_004431 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available stal ... Structure Of Vshp_bpp21 In Space Group C2 pdb|1TD3|B ... Chain B, Crystal Structure Of Vshp_bpp21 In Space...f Vshp_bpp21 ... In Space Group C2 gb|AAA32345.1| capsid protein small ... subunit ... L

  7. Author Details

    African Journals Online (AJOL)

    Meiotic study of Acrida turrita (Linnaeus 1758), Paracinema luculenta Karsch 1896 and Morphacris fasciata (Thunberg 1815) (Orthoptera: Acrididae) Abstract PDF · Vol 6, No 4 (2012) - Articles Cytogenetic characterization of Taphronota thaelephora Stal. 1873. (Orthoptera: Pyrgomorphidae) from Cameroon. II. Description of ...

  8. Author Details

    African Journals Online (AJOL)

    Focho, DA. Vol 2, No 1 (2002) - Articles Observations on the Meiotic Process in the African Pest Grasshopper Taphronota thaelephora Stal. (Orthoptera : Pyrgomorphidae) Details PDF · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's ...

  9. Invloed krachtvoerniveau op vleesproduktiekenmerken van Piemontese met zwartbont kruislingstieren

    NARCIS (Netherlands)

    Hanekamp, W.J.A.

    1989-01-01

    Met 3 ronden van elk 36 Piemontese X zwartbonte kruislingstieren is het effect van extra krachtvoer vergeleken met de normaal gangbare gift naast onbeperkt snijmaoskuil. De stieren waren gehuisvest in een natuurlijk geventileerde stal (space-boarding)en op een volledige roostervloer.

  10. CTC Sentinel. Volume 3, Number 11-12, November 2010

    Science.gov (United States)

    2010-11-01

    discrete ethnic and geographic entities, Umarov’s imagined community lacks meaningful cohesion. These deficiencies inform the fragmentation now evident...with more than 20 local commanders flocking to the troika’s banner.20 15 “Amir IK Dokku Abu Usman obyavil o svoem preem- nike . Im stal Amir

  11. Effect of Al doping on microstructure and optical band gap of ZnO ...

    Indian Academy of Sciences (India)

    micrograph shows that pure ZnO particles are spherical shaped. ... tions) on the other hand, are versatile, simple and cost-effective compared to ..... [45] G Knuyt, C Quaeyhagens, J D'Haen and L M Stals, Thin Solid Films 258, 159 (1995).

  12. A prospective study comparing the efficacy and safety of two sublingual birch allergen preparations

    NARCIS (Netherlands)

    Klimek, Ludger; Sperl, Annette; van Twuijver, Esther; van Ree, Ronald; Kleinjans, Huub; Boot, Johan Diderik; Pfaar, Oliver

    2014-01-01

    Background: SUBLIVAC FIX Birch (SUB-B) is a liquid oral preparation of Betula verrucosa pollen extract for the treatment of allergic rhinitis/rhinoconjuctivitis induced by birch pollen. The major allergen content of SUB-B and Staloral Birch (Stal-B) have been shown to be comparable. In order to

  13. Diervriendelijk dieren houden zonder rugklachten

    NARCIS (Netherlands)

    Roelofs, H.; Vermeer, H.M.

    2007-01-01

    Onderzoekers hebben de fysieke belasting van diervriendelijke systemen in de varkens- en leghennenhouderij vergeleken met die op gangbare gezinsbedrijven. Het blijkt dat bij de (ver)bouw van een diervriendelijke stal de hoeveelheid arbeid en fysieke belasting is te beperken door rekening te houden

  14. Onderzoek naar de ammoniak- en geuremissie van stallen LVI : scharrelstal voor leghennen met frequente mest- en strooiselverwijdering = Free range housing system for laying hens with frequent manure and litter removal

    NARCIS (Netherlands)

    Scheer, A.; Hol, J.G.M.; Mol, G.

    2002-01-01

    Door IMAG werd onderzoek verricht naar de ammoniak- en geuremissie van een scharrelstal voor leghennen met volledige ontmesting. Het ammoniakemissiereducerend principe berustte op het eenmaal per week verwijderen van de mest onder de beun en het strooisel in de stal. Hiervoor werden met behulp van

  15. Waterverdamping uit dunne mest; resultaten van modelberekeningen

    NARCIS (Netherlands)

    Wagenberg, van A.V.; Verdoes, N.; Vranken, E.; Berckmans, D.

    1999-01-01

    In een geïntegreerd luchtbehandelingsysteem kunnen technische oplossingen voor de emissieproblematiek (ammoniak, geur) en de mestproblematiek worden gecombineerd. Door ventilatielucht uit de stal intensief in contact te brengen met mest kan water uit de mest verdampen. Daardoor droogt de mest. Het

  16. ALGUNAS INVESTIGACIONES DEL DR. GROOT EN LA REVISTA MEDICINA. RESEÑA HISTÓRICA DE ALGUNOS ESTUDIOS COLOMBIANOS SOBRE TRYPANOSOMA RANGELI

    Directory of Open Access Journals (Sweden)

    Hernando Groot Liévano

    2016-12-01

    Full Text Available

    Artículo publicado en la revista MEDICINA Vol. 22 (2 del año 2000.

    Parecerá extraño que uno de los primeros artículos de esta revista no se refiera a la enfermedad de Chagas. Tanto es así que cuando el doctor Felipe Guhl tuvo la idea de llamarme para esta presentación, mi primera respuesta fue negativa porque, obviamente debería hablarse del Trvpanosoma cruzi y no del Trypanosoma rangeli. El presente artículo es un breve recuento de mi experiencia con este parásito y su importancia dado que coexiste con el T. cruzi y que, en ocasiones, la diferenciación morfológica entre los dos no es tan clara cuando se examinan preparaciones de sangre en ‘gota gruesa’ de vertebrados o preparaciones del contenido intestinal de los insectos vectores, y además porque tiene ciertas relaciones inmunológicas que es necesario tener en cuenta para evitar posibles confusiones. Por otra parte, su distribución geográfica es muy amplia extendiéndose desde México hasta el Perú y el Brasil.

    El Trypanosoma rangeli fue llamado así por un distinguido médico y posteriormente diplomático de Venezuela, el doctor Enrique Tejera, quien encontró en los chipos, o sea en los Rhodnius prolixus de Venezuela, un pequeño flagelado muy largo, bastante diferente del T. cruzi y resolvió ponerle el nombre de Trypanosoma o Crithidia rangeli, pues no estaba muy seguro del género en el cual debía colocarlo. Evidentemente, sólo había visto la morfología de estos flagelados en el intestino de los Rhodnius y, por consiguiente, no tenía ningún otro elemento para identificarlos. Únicamente comprobó que eran diferentes del T. cruzi.

    ¿Por qué le dedicó su descubrimiento a Rangel? Creo que es importante que nosotros los latinoamericanos conozcamos bien los valores científicos que han habido en nuestros países y en vez de preocuparnos por las artificiales fronteras políticas, lo cual en nada contribuye al progreso de la

  17. Enfermedad de Chagas y Colonización en el Alto Catatumbo

    Directory of Open Access Journals (Sweden)

    Felipe Guhr

    1992-03-01

    Full Text Available

    Introducción
    El protozoario parásito Trypanosoma cruzi, agente causal de la enfermedad de Chagas, infecta alrededor de 10 millones de individuos en Latinoamérica pudiendo ocasionarse en algunos de ellos, patologías cardíacas o digestivas.

    En Colombia, el T.cruzi se detecta frecuentemente en el Valle del Río Magdalena en la región del Catatumbo, la Sierra Nevada de Santa Marta y los Llanos Orientales.

    Se estima que alrededor de17% de la población colombiana está infectada y cerca del 23% se encuentra bajo riesgo de adquirir la infección dependiendo de la distribución de los vectores (l.

    Se han reportado 17 especies de triatomineos en el país y en siete de ellas se ha demostrado la presencia del parásito. Rhodnius prolixus es el insecto vector de mayor distribución en las áreas endémicas debido a sus hábitos antropofílicos y domiciliarios (2.

    El esquema tradicional de la cadena epidemiológica de 1′. cruzi muestra que la transmisión estuvo primitivamente restringida a ciclos específicos en el ambiente selvático donde triatomineos silvestres acometían mamíferos pequeños y medianos en vastas extensiones del Continente Americano, sin que el hombre interviniera en este ciclo natural.

    Esta situación persiste hasta hoy en regiones vírgenes de América configurándose el carácter epidemiológico de una enzootia silvestre (figura 1.

    La presencia de T. cruzi parece no afectar significativamente a los triatomineos ni a los mamíferos silvestres naturales infectados, lo que sugiere un equilibrio entre las especies, fruto de largos períodos de adaptación. Es común encontrar mamíferos portadores de T. cruzi en el país; por ejemplo, se ha descrito más de un centenar de reservorios pertenecientes a especies diferentes (1.

    La existencia de la enfermedad de Chagas humana es un hecho puramente accidental. En la medida en que el hombre fue entrando en contacto con los focos

  18. Fluidized bed combustion research and development in Sweden: A historical survey

    Directory of Open Access Journals (Sweden)

    Leckner Bo.

    2003-01-01

    Full Text Available A survey is made on research and development related to fluidized bed boilers in Sweden during the past two decades, where several Swedish enterprises took part: Generator, Götaverken, Stal Laval (ABB Carbon and Studsvik. Chalmers University of Technology contributed in the field of research related to emissions, heat transfer and fluid dynamics, and some results from this activity are briefly summarized.

  19. INTERNATIONAL SURVEY OF PUBLICATIONS IN INTERNATIONAL BUSINESS: RISING THROUGH THE BASE OF WEB SCIENCE

    OpenAIRE

    Carpes, Aletéia de Moura; Velter, Aline Nadalin; Scherer, Flavia Luciane; Lütz, Carolina

    2011-01-01

    Internationalization is an alternative to business growth, allowing its exposure to international standards of products, technologies and management methods, generating significant returns for domestic transactions (STAL, 2010). The evolution of commercial transactions between the countries have brought a lot of issues to be understood, that seek to check the reflection of international activity in the individual, company and nation experiencing this context of globalization. This article was...

  20. Journal of Biosciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Habitat change in Rhodnius spp may represent an environmental challenge for the development of the species, particularly when feeding frequency and population density vary in nature. To estimate the effect of these variables in stability on development, the degree of directional asymmetry (DA) and fluctuating asymmetry ...

  1. American Trypanosomiasis

    Science.gov (United States)

    2011-06-01

    infected reduviid bugs, including Triatoma sp, Panstron- gylus sp, and Rhodnius sp (Figs 2.9 & 2.10). These large bugs (sometimes called kissing or...cause abor- tion of the fetus or its premature delivery by the infected mother . Congenitally acquired infection may be asymptom- atic or it may

  2. Letterman Army Institute of Research Annual Research Progress Report, FY 1981.

    Science.gov (United States)

    1981-10-01

    five species of mosquitoes. These compounds were tested against sand flies ( Lutzomyia longipalpis), fleas (Xenopsylla cheopis ) and bugs (Rhodnius...BUESCHER, M.D., L.C. RUTLEDGE, R.A. WIRTZ, K.B. GLACKIN, and M.A. MOUSSA. Laboratory tests of repellents against Lutzomyia longipalpis (Diptera

  3. Distribuição espacial de populações de triatomíneos (Hemiptera: Reduviidae em palmeiras da espécie Mauritia flexuosa no Distrito Federal, Brasil Spatial distribution of Triatominae populations (Hemiptera: Reduviidae in Mauritia flexuosa palm trees in Federal District of Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Gurgel-Gonçalves

    2004-06-01

    Full Text Available Para determinar e analisar a distribuição espacial de populações silvestres de triatomíneos no Distrito Federal, Brasil, foram amostradas 150 palmeiras da espécie Mauritia flexuosa em seis veredas de diferentes paisagens (silvestre, rural e periurbana na estação chuvosa. Os triatomíneos foram identificados morfologicamente, separados por sexo e estadio ninfal e examinados para verificar infecção por Trypanosoma cruzi e Trypanosoma rangeli. Vinte e oito (18,6% palmeiras estavam infestadas por Rhodnius neglectus e 14 (9,5% por Psammolestes tertius. A freqüência dessas espécies em palmeiras com e sem ninhos foi significativamente diferente, sendo superior nas palmeiras com ninhos de aves e mamíferos na copa. O maior número médio de insetos/palmeira foi observado nas áreas rurais, com estimativas de até 838 insetos/hectare. A composição etária das espécies apresentou um padrão diferente, Rhodnius neglectus com predomínio de ninfas e Psammolestes tertius com predomínio de adultos, sendo que muitos ovos de Rhodnius neglectus foram coletados indicando um evento reprodutivo em fevereiro de 2003. Entre os ninhos encontrados nas palmeiras, o do pássaro Phacellodomus ruber (Furnariidae apresentou as maiores abundâncias de triatomíneos, ocorrendo em 42% das palmeiras. A abundância relativa de Rhodnius neglectus e Psammolestes tertius foi maior em áreas rurais que possuíram maior número de ninhos nas palmeiras e menor densidade de palmeiras por hectare. Nenhum dos 96 triatomíneos examinados estava infectado por Trypanosoma cruzi ou Trypanosoma rangeli, apesar de encontrarmos infecção de Rhodnius neglectus por esses parasitas em estudos anteriores.To determine and analyze the distribution of Triatominae sylvatic populations in the Federal District of Brazil, 150 Mauritia flexuosa palm trees were sampled in six veredas of different landscapes (sylvatic, rural and peri-urban in the rainy season. Triatomines were

  4. Efficacy of a tool to predict short-term mortality in older people presenting at emergency departments: Protocol for a multi-centre cohort study.

    Science.gov (United States)

    Cardona, Magnolia; Lewis, Ebony T; Turner, Robin M; Alkhouri, Hatem; Asha, Stephen; Mackenzie, John; Perkins, Margaret; Suri, Sam; Holdgate, Anna; Winoto, Luis; Chang, Chan-Wei; Gallego-Luxan, Blanca; McCarthy, Sally; Kristensen, Mette R; O'Sullivan, Michael; Skjøt-Arkil, Helene; Ekmann, Anette A; Nygaard, Hanne H; Jensen, Jonas J; Jensen, Rune O; Pedersen, Jonas L; Breen, Dorothy; Petersen, John A; Jensen, Birgitte N; Mogensen, Christian Backer; Hillman, Ken; Brabrand, Mikkel

    Prognostic uncertainty inhibits clinicians from initiating timely end-of-life discussions and advance care planning. This study evaluates the efficacy of the CriSTAL (Criteria for Screening and Triaging to Appropriate aLternative care) checklist in emergency departments. Prospective cohort study of patients aged ≥65 years with any diagnosis admitted via emergency departments in ten hospitals in Australia, Denmark and Ireland. Electronic and paper clinical records will be used to extract risk factors such as nursing home residency, physiological deterioration warranting a rapid response call, personal history of active chronic disease, history of hospitalisations or intensive care unit admission in the past year, evidence of proteinuria or ECG abnormalities, and evidence of frailty to be concurrently measured with Fried Score and Clinical Frailty Scale. Patients or their informal caregivers will be contacted by telephone around three months after initial assessment to ascertain survival, self-reported health, post-discharge frailty and health service utilisation since discharge. Logistic regression and bootstrapping techniques and AUROC curves will be used to test the predictive accuracy of CriSTAL for death within 90 days of admission and in-hospital death. The CriSTAL checklist is an objective and practical tool for use in emergency departments among older patients to determine individual probability of death in the short-term. Its validation in this cohort is expected to reduce clinicians' prognostic uncertainty on the time to patients' death and encourage timely end-of-life conversations to support clinical decisions with older frail patients and their families about their imminent or future care choices. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Jet spoiler arrangement for wind turbine

    Science.gov (United States)

    Cyrus, J. D.; Kablec, E. G.; Klimas, P. C.

    1983-09-01

    An air jet spoiler arrangement is provided for a Darrieus-type vertical axis wind-powered turbine. Air is drawn into hollow turbine blades through air inlets at the end thereof and is ejected in the form of air jets through small holes or openings provided along the lengths of the blades. The air jets create flow separation at the surfaces of the turbine blades, thereby including stal conditions and reducing the output power. A feedback control unit senses the power output of the turbine and controls the amount of air drawn into the air inlets accordingly.

  6. Archeological Investigations in the Truscott Reservoir Area. King and Knox Counties, Texas,

    Science.gov (United States)

    1978-06-01

    postdate the deposit. Collections consist of an upper molar of Equus sp., two di’stal epiphyses of metapodials of Bison sp., a glenoid fossa of a...includes two lower molars of Equus sp., a fragment of a jaw condyle, and a rib fragment. Since very little material was found at any of these sites, and...Archeological Survey Report No. 6. Austin. 364 McCormick, Olin F. 1976 The Archaic Period in North Central Texas. In The Texas Archaic: A Symposium, edited

  7. Differential pathogenicity of Metarhizium anisopliae and the control of the sugarcane root spittlebug Mahanarva fimbriolata

    Directory of Open Access Journals (Sweden)

    Patricia Vieira Tiago

    2011-06-01

    Full Text Available In order to assess the effectiveness of Metarhizium anisopliae var. anisopliae (Metschnikoff Sorokin isolates in controlling the sugarcane root spittlebug Mahanarva fimbriolata (Stal (Hemiptera: Cercopidae, nine isolates obtained from a single geographical region were studied. 'Confirmed cumulative' and 'corrected cumulative' spittlebug mortality rates were measured for each of the isolates. Based on the confirmed mortality curve, the isolates URM5946, URM5951 and URM6033 were considered to be potentially the most effective in a biological control program for M. fimbriolata.

  8. Triatominos del departamento de San Martín, Perú, 2005

    OpenAIRE

    Cáceres, Abraham; Zavaleta, Gina; Ruiz, Juan; Vega, Silvia; Arevalo, Heriberto; Náquira, César

    2005-01-01

    La presencia de los triatominos transmisores de Trypanosoma cruzi y Trypanosoma rangeli ha sido reportada en todos los departamentos del Perú, excepto en Huancavelica. En el sudoeste, el Triatoma infestans es de hábitos domiciliarios y en la zona norte y nororiente hay numerosas especies de hábitos intradomiciliarios (Panstrongylus herreri, Rhodnius ecuadoriensis) aunque ocasionalmente ingresan a las viviendas (T. Carroni, P. geniculatus, P. chinai), mientras que otras son de hábitos silvestr...

  9. Attraction of Chagas disease vectors (Triatominae) to artificial light sources in the canopy of primary Amazon rainforest.

    Science.gov (United States)

    Castro, Marcelo C M; Barrett, Toby V; Santos, Walter S; Abad-Franch, Fernando; Rafael, José A

    2010-12-01

    Adult triatomines occasionally fly into artificially lit premises in Amazonia. This can result in Trypanosoma cruzi transmission to humans either by direct contact or via foodstuff contamination, but the frequency of such behaviour has not been quantified. To address this issue, a light-trap was set 45 m above ground in primary rainforest near Manaus, state of Amazonas, Brazil and operated monthly for three consecutive nights over the course of one year (432 trap-hours). The most commonly caught reduviids were triatomines, including 38 Panstrongylus geniculatus, nine Panstrongylus lignarius, three Panstrongylus rufotuberculatus, five Rhodnius robustus, two Rhodnius pictipes, one Rhodnius amazonicus and 17 Eratyrus mucronatus. Males were collected more frequently than females. The only month without any catches was May. Attraction of most of the known local T. cruzi vectors to artificial light sources is common and year-round in the Amazon rainforest, implying that they may often invade premises built near forest edges and thus become involved in disease transmission. Consequently, effective Chagas disease prevention in Amazonia will require integrating entomological surveillance with the currently used epidemiological surveillance.

  10. Attraction of Chagas disease vectors (Triatominae to artificial light sources in the canopy of primary Amazon rainforest

    Directory of Open Access Journals (Sweden)

    Marcelo CM Castro

    2010-12-01

    Full Text Available Adult triatomines occasionally fly into artificially lit premises in Amazonia. This can result in Trypanosoma cruzi transmission to humans either by direct contact or via foodstuff contamination, but the frequency of such behaviour has not been quantified. To address this issue, a light-trap was set 45 m above ground in primary rainforest near Manaus, state of Amazonas, Brazil and operated monthly for three consecutive nights over the course of one year (432 trap-hours. The most commonly caught reduviids were triatomines, including 38 Panstrongylus geniculatus, nine Panstrongylus lignarius, three Panstrongylus rufotuberculatus, five Rhodnius robustus, two Rhodnius pictipes, one Rhodnius amazonicus and 17 Eratyrus mucronatus. Males were collected more frequently than females. The only month without any catches was May. Attraction of most of the known local T. cruzi vectors to artificial light sources is common and year-round in the Amazon rainforest, implying that they may often invade premises built near forest edges and thus become involved in disease transmission. Consequently, effective Chagas disease prevention in Amazonia will require integrating entomological surveillance with the currently used epidemiological surveillance.

  11. UCLA space-time area law model: A persuasive foundation for hadronization

    International Nuclear Information System (INIS)

    Abachi, S.; Buchanan, C.; Chien, A.; Chun, S.; Hartfiel, B.

    2007-01-01

    From the studies of rates and distributions of heavy quark (c,b) mesons we have developed additional evidence that hadron formation, at least in the simplest environment of e + e - collisions, is dominantly controlled by a space-time area law (''STAL''), an approach suggested by both non-perturbative QCD and relativistic string models. From the dynamics of heavy quarks whose classical space-time world-lines deviate significantly from the light-cone, we report the exact calculation of the relevant space-time area and the derivation of a Lorentz invariant variable, z eff , which reduces to the light-cone momentum fraction z for low mass quarks. Using z eff in the exponent of our fragmentation function in place of z, we find persuasive agreement with L=0,1 charmed and bottom meson data as well as for u,d,s L=0 states. Presuming STAL to be a valid first-order description for all these meson data, we find the scale of other possible second-order effects to be limited to ∝20% or less of the observed rates. The model favors a b-quark mass of ∝4.5 GeV. (orig.)

  12. MOD-AGE - an algorithm for age-depth model construction; U-series dated speleothems case study

    Science.gov (United States)

    Hercman, H.; Pawlak, J.

    2012-04-01

    We present MOD-AGE - a new system for chronology construction. MOD-AGE can be used for profiles that have been dated by different methods. As input data, the system uses the following basic measurements: activities, atomic ratios or age, as well as depth measurement. Based on probability distributions describing the measurement results, MOD-AGE estimates the age~depth relation and its confidence bands. To avoid the use of difficult-to-meet assumptions, MOD-AGE uses nonparametric methods. We applied a Monte Carlo simulation to model age and depth values based on the real distribution of counted data (activities, atomic ratios, depths etc.). Several fitting methods could be applied for estimating the relationships; based on several tests, we decide to use LOESS method (locally weighted scatterplot smoothing). The stratigraphic correction procedure applied in the MOD-AGE program uses a probability calculus, which assumes that the ages of all the samples are correctly estimated. Information about the probability distribution of the samples' ages is used to estimate the most probable sequence that is concordant according to the superposition rule. MOD-AGE is presented as a tool for the chronology construction of speleothems that have been analyzed by the U-series method, and it is compared to the StalAge algorithm presented by D. Scholtz and D.L Hoffmann (2011). Scholtz, D., Hoffmann, D. L., 2011. StalAge - An algorithm designed for construction of speleothem age models. Quaternary Geochronology 6, 369-382.

  13. Thermomechanical fatigue in single crystal superalloys

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    Moverare Johan J.

    2014-01-01

    Full Text Available Thermomechanical fatigue (TMF is a mechanism of deformation which is growing in importance due to the efficiency of modern cooling systems and the manner in which turbines and associated turbomachinery are now being operated. Unfortunately, at the present time, relatively little research has been carried out particularly on TMF of single crystal (SX superalloys, probably because the testing is significantly more challenging than the more standard creep and low cycle fatigue (LCF cases; the scarcity and relative expense of the material are additional factors. In this paper, the authors summarise their experiences on the TMF testing of SX superalloys, built up over several years. Emphasis is placed upon describing: (i the nature of the testing method, the challenges involved in ensuring that an given testing methodology is representative of engine conditions (ii the behaviour of a typical Re-containing second generation alloy such as CMSX-4, and its differing performance in out-of-phase/in-phase loading and crystallographic orientation and (iii the differences in behaviour displayed by the Re-containing alloys and new Re-free variants such as STAL15. It is demonstrated that the Re-containing superalloys are prone to different degradation mechanisms involving for example microtwinning, TCP precipitation and recrystallisation. The performance of STAL15 is not too inferior to alloys such as CMSX-4, suggesting that creep resistance itself does not correlate strongly with resistance to TMF. The implications for alloy design efforts are discussed.

  14. Production and physicochemical assessment of new stevia amino acid sweeteners from the natural stevioside.

    Science.gov (United States)

    Khattab, Sherine N; Massoud, Mona I; Jad, Yahya El-Sayed; Bekhit, Adnan A; El-Faham, Ayman

    2015-04-15

    New stevia amino acid sweeteners, stevia glycine ethyl ester (ST-GL) and stevia l-alanine methyl ester (ST-GL), were synthesised and characterised by IR, NMR ((1)H NMR and (13)C NMR) and elemental analysis. The purity of the new sweeteners was determined by HPLC and their sensory properties were evaluated relative to sucrose in an aqueous system. Furthermore, the stevia derivatives (ST-GL and ST-AL) were evaluated for their acute toxicity, melting point, solubility and heat stability. The novel sweeteners were stable in acidic, neutral or basic aqueous solutions maintained at 100 °C for 2 h. The sweetness intensity rate of the novel sweeteners was higher than sucrose. Stevia amino acid (ST-GL and ST-AL) solutions had a clean sweetness taste without bitterness when compared to stevioside. The novel sweeteners can be utilised as non-caloric sweeteners in the production of low-calorie food. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Distribution of triatomine species in domestic and peridomestic environments in central coastal Ecuador

    Science.gov (United States)

    Villacís, Anita G.; Moncayo, Ana L.; Ocaña-Mayorga, Sofia; Yumiseva, Cesar A.; Baus, Esteban G.

    2017-01-01

    Background Although the central coast of the Ecuador is considered endemic for Chagas disease, few studies have focused on determining the risk of transmission in this region. In this study we describe the triatomine household infestation in Manabí province (Central Coast region), determine the rate of Trypanosoma cruzi infection and study the risk factors associated with infestation by Rhodnius ecuadoriensis. Methodology/Principal findings An entomological survey found three triatomine species (Rhodnius ecuadoriensis, Panstrongylus rufotuberculatus and P. howardi) infesting domiciles in 47.4% of the 78 communities visited (total infestation rate of 4.5%). Four percent of domiciles were infested, and nymphs were observed in 77% of those domiciles. The three species were found in altitudes below 500 masl and in all ecological zones except cloud forest. Within the domicile, we found the three species mostly in bedrooms. Rhodnius ecuadoriensis and P. rufotuberculatus were abundant in bird nests, including chicken coops and P. howardi associated with rats in piles of bricks, in the peridomicile. Triatomine infestation was characterized by high rates of colonization, especially in peridomicile. Flagelates infection was detected in only 12% of the samples by microscopy and Trypanosoma cruzi infection in 42% of the examined triatomines by PCR (n = 372). The most important risk factors for house infestation by R. ecuadoriensis were ecological zone (w = 0.99) and presence of chickens (w = 0.96). Determinants of secondary importance were reporting no insecticide applications over the last twelve months (w = 0.86) and dirt floor (w = 0.70). On the other hand, wood as wall material was a protective factor (w = 0.85). Conclusion/Significance According the results, approximately 571,000 people would be at high risk for T. cruzi infection in Manabí province. A multidisciplinary approximation and the adhesion to a periodic integrated vector management (IVM) program are essential

  16. Distribution of triatomine species in domestic and peridomestic environments in central coastal Ecuador.

    Directory of Open Access Journals (Sweden)

    Mario J Grijalva

    2017-10-01

    Full Text Available Although the central coast of the Ecuador is considered endemic for Chagas disease, few studies have focused on determining the risk of transmission in this region. In this study we describe the triatomine household infestation in Manabí province (Central Coast region, determine the rate of Trypanosoma cruzi infection and study the risk factors associated with infestation by Rhodnius ecuadoriensis.An entomological survey found three triatomine species (Rhodnius ecuadoriensis, Panstrongylus rufotuberculatus and P. howardi infesting domiciles in 47.4% of the 78 communities visited (total infestation rate of 4.5%. Four percent of domiciles were infested, and nymphs were observed in 77% of those domiciles. The three species were found in altitudes below 500 masl and in all ecological zones except cloud forest. Within the domicile, we found the three species mostly in bedrooms. Rhodnius ecuadoriensis and P. rufotuberculatus were abundant in bird nests, including chicken coops and P. howardi associated with rats in piles of bricks, in the peridomicile. Triatomine infestation was characterized by high rates of colonization, especially in peridomicile. Flagelates infection was detected in only 12% of the samples by microscopy and Trypanosoma cruzi infection in 42% of the examined triatomines by PCR (n = 372. The most important risk factors for house infestation by R. ecuadoriensis were ecological zone (w = 0.99 and presence of chickens (w = 0.96. Determinants of secondary importance were reporting no insecticide applications over the last twelve months (w = 0.86 and dirt floor (w = 0.70. On the other hand, wood as wall material was a protective factor (w = 0.85.According the results, approximately 571,000 people would be at high risk for T. cruzi infection in Manabí province. A multidisciplinary approximation and the adhesion to a periodic integrated vector management (IVM program are essential to guarantee sustainable preventive and control

  17. Sexual distinction between 5th instar nymphs of six species of Triatominae (Hemiptera, Reduviidae

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    João Aristeu da Rosa

    1992-06-01

    Full Text Available The aim of this paper is to present the analysis of sexual morphological differences observed in 5th instar nymphs of the following species: Panstrongylus megistus; Rhodnius neglectus; Triatoma brasiliensis; T. infestans; T. matogrosensis and T. tibiamaculata. Male and female nymphs were examined and photographed with a Scanning Electron Microscope. The 9th segment dimensions of dorsal and ventral faces were determined through a Profile Projector. Results and statistical analysis showed significant differences: the 9th sternite is significantly broader in male than female nymphs, while in five species; tergites in female nymphs are broad and in male are narrow.

  18. [Triatominae and Cactaceae: a risk for the transmission of the American trypanosomiasis in the peridomicilary space (Northeast Brazil)].

    Science.gov (United States)

    Emperaire, L; Romaña, C A

    2006-06-01

    Field observations carried in semi-arid Brazil Northeast point out the frequent association, in the peridomiciliary space, between a cactus, Cereus jamacaru, the occurrence of nests in its branches and the occurrence of two species of insects vectors of Trypanosoma cruzi, pathogenic agent of Chagas disease: Rhodnius neglectus and Triatoma pseudomaculata. The analysis of the architectural variables of this Cactaceae shows that the presence of nests, and thus of insects, depends on the traditional practices of management of this cactus. This study underlines the relevance of an integrated approach of the ecology of Triatominae for the identification of factors of risk.

  19. Digamacris n. gen. (Orthoptera, Acrididae, Melanoplinae de la region atlantica meridional de Brasil Digamacris n. gen. (Orthoptera, Acrididae, Melanoplinae from the Atlantic Meridional region of Brazil

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    Carlos S. Carbonell

    1989-01-01

    Full Text Available Digamacris, a new genus of the Dichroplini (Acrididae, Melanoplinae is described for the species Pezotettix amoenus Stal, 1878 and Dichroplus fratemus Carl, 1916, both included at present in the genus Dichroplus. These species live in edges and clearings of the Atlantic Forest (Mata Atlantica of Brazil. D. fratemus is found in the states of Minas Gerais, Espirito Santo and Rio de Janeiro east of the Bay of Guanabara. D. amoenus in the state of Rio de Janeiro W. of the Bay of Guanabara and in the coastal area of the state of São Paulo. The species are illustrated and redescribed. Both have two neatly different chromatic forms of females, while the males are uniform in coloration and closely correspond with one of the female forms.

  20. THE ROLES OF DETOXIFYING ENZYMES AND AChE INSENSITIVITY IN METHAMIDOPHOS RESISTANCE DEVELOPMENT AND DECLINE IN NILAPARVATA LUGENS

    Institute of Scientific and Technical Information of China (English)

    Ze-wenLiu; Zhao-junHan; Ling-chunZhang

    2003-01-01

    Methamidophos resistance of brown planthopper (Nilaparvata lugens Stal, BPH) was selected in laboratory. After successive selection for 9 generations, the selection was ceased by rearing BPH without contact with any insecticide for 9 generations. In the full course, the successive changes of esterase activity, MFO activity, GSTs activity and AChE insensitivity were analyzed. The results showed that the change of esterase activity was high correlated with that of methamidophos in the full course, which indicated that esterase played very important role both in the resistance development and in the resistance decline. However, the change of AChE insensitivity only significantly correlated with that of resistance in the development stage, and the change of MFO activity or GSTs activity only significantly correlated with that of the resistance in the decline stage, which indicated the changes of AChE insensitivity, MFO activity or GSTs activity only played some roles in different stages of the resistance change.

  1. An analysis of the fate of eggs of Gratiana spadicea (Klug, 1829 (Coleoptera: Chrysomelidae: Cassidinae in relation to the position in the ootheca

    Directory of Open Access Journals (Sweden)

    Miriam Becker

    1987-01-01

    Full Text Available Randomly sampled oothecae of a natural population of Gratiana spadicea from the outskirts of Porto Alegre, RS, were dissected. The overlapping of the egg membranes makes possible to enumerate the eggs in a batch and therefore to relate mortality to position in the ootheca. The ootheca of this cassid provides a spatial refuge for some of its eggs. Successful eggs of G. spadicea amounted to less than one fifth of the total in each batch. Parasitoids and predators were responsible for a high mortality of eggs whatever the size of the ootheca. The main cause of mortality was the eulophid wasp Emersonella ooecia De Santis, 1983. A large proportion of eggs were sucked dry by the mirid Tupiocoris cincticornis (Stal, 1860. The sucked eggs could have contained either the embryo of G. spadicea or the parasitoid in the pre-emergence stages.

  2. Tensile Instability and Artificial Stresses in Impact Problems in SPH

    International Nuclear Information System (INIS)

    Mehra, Vishal; Sijoy C D; Mishra, Vinayak; Chaturvedi, Shashank

    2012-01-01

    The smooth particle hydrodynamics (SPH) is a meshless computational technique that is popular in the modeling of impact and penetration problems. However, SPH is liable to a tensile instability that manifests itself as a bunching of nodes and formation of artificial voids and no generally accepted formulation exists to counter this instability. We examine the performance of two methods that have been proposed to deal with the tensile instability— the Monaghan artificial stresses and the Godunov-type SPH. The impact and penetration of 0.5 cm radii steel spheres on 2 mm thick aluminium plate at 3.1 km/s is chosen for comparison. We show that the artificial void formation in St-Al impact is suppressed but not eliminated by using Monaghan stresses while the void formation is entirely eliminated by using Godunov-type formulation of SPH that was proposed by Parshikov and Medin.

  3. Distribuição Geográfica e Dispersão Alti-latitudinal de Alguns Gêneros e Espécies da Tribo Triatomini Jeannel, 1919 (Hemiptera, Reduviidae, Triatominae

    Directory of Open Access Journals (Sweden)

    Galvão Cleber

    1998-01-01

    Full Text Available Geographical Distribution and Alti-latitudinal Dispersion of Some Genera and Species of the Tribe Triatomini Jeannel, 1919 (Hemiptera, Reduviidae, Triatominae - With the currently known distribution of genera and species of the tribe Triatomini Jeannel, 1919, maps and diagrams were prepared, showing the geographical area occupied by the species and their respective dispersion in grades of latitude and altitude. Two genera are not treated: Panstrongylus Berg, 1879, already published and Triatoma Laporte, 1832, that is being published partially in several articles. Genus Eratyrus Stal, 1859, has two species, while Dipetalogaster Usinger, 1939, Mepraia Mazza, Gajardo & Joerg, 1940, Paratriatoma Barber, 1938 and recently created genus Hermanlentia Jurberg & Galvão, 1997, have only one each. The study of these maps and diagrams permits a better knowledge about some ecological requirements of Chagas' disease vectors and detects gaps in the geographical distribution, where the species were not found but probably they could be prevalent

  4. The chemical volatiles (semiochemicals) produced by neo tropical stink bugs (Hemiptera: Pentatomidae)

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Maria C.B.; Pareja, Martin; Laumann, Raul A.; Borges, Miguel [EMBRAPA Recursos Geneticos e Biotecnologia, Brasilia, DF (Brazil). Nucleo Tematico Controle Biologico

    2008-09-15

    In recent years the growing concern about environmental changes and how we are using the natural resources have triggered a search for natural products as alternatives to synthetic pesticides. The stink bugs produce a wide variety of chemical compounds (semiochemicals) that show potential to manage these insects. The stink bugs Chinavia impicticornis (Stal), C. ubica (Rolston), Dichelops melacanthus (Dallas), Euschistus heros (F.), Piezodorus guildinii (Westwood), Thyanta perditor (Westwood) and Tibraca limbativentris (Stal) had their blends of defensive compounds evaluated both qualitative and quantitatively. The main compounds identified on the glands of Brazilian stink bugs are: 2-alkenals, mainly the E isomer; saturated aliphatic hydrocarbons; and 4 oxo-(E)-2-alkenals. The first sex attractant determined from a stink bug was obtained from Nezara viridula L., and consists on a mix of two isomers cis - and trans bisabolene-epoxides. Later the soybean stink bug E. heros was also studied and its sex attractant was identified as three esters methyl: 2,6,10-trimethyl decanoate, methyl 2,6,10-trimethyl dodecanoate, and methyl E2, Z4-decadienoate. Recently, three new Brazilian sting bugs were studied and had their sex attractant elucidated. Males of T. perditor produce the ester, methyl 2E, 4Z, 6Z-decatrienoate. Whereas, the stink bug, P. guildinii has as sexual pheromone, the sesquiterpene beta-sesqui phellandrene, and the stink bug T. limbativentris produces as sex attractant the zingiberenol. In this review we discuss the advances obtained on the behaviour and identification of sex and defensive compound of stink bugs from Brazilian crops and the application of this knowledge to manage the stink bugs. (author)

  5. The chemical volatiles (semiochemicals) produced by neo tropical stink bugs (Hemiptera: Pentatomidae)

    International Nuclear Information System (INIS)

    Moraes, Maria C.B.; Pareja, Martin; Laumann, Raul A.; Borges, Miguel

    2008-01-01

    In recent years the growing concern about environmental changes and how we are using the natural resources have triggered a search for natural products as alternatives to synthetic pesticides. The stink bugs produce a wide variety of chemical compounds (semiochemicals) that show potential to manage these insects. The stink bugs Chinavia impicticornis (Stal), C. ubica (Rolston), Dichelops melacanthus (Dallas), Euschistus heros (F.), Piezodorus guildinii (Westwood), Thyanta perditor (Westwood) and Tibraca limbativentris (Stal) had their blends of defensive compounds evaluated both qualitative and quantitatively. The main compounds identified on the glands of Brazilian stink bugs are: 2-alkenals, mainly the E isomer; saturated aliphatic hydrocarbons; and 4 oxo-(E)-2-alkenals. The first sex attractant determined from a stink bug was obtained from Nezara viridula L., and consists on a mix of two isomers cis - and trans bisabolene-epoxides. Later the soybean stink bug E. heros was also studied and its sex attractant was identified as three esters methyl: 2,6,10-trimethyl decanoate, methyl 2,6,10-trimethyl dodecanoate, and methyl E2, Z4-decadienoate. Recently, three new Brazilian sting bugs were studied and had their sex attractant elucidated. Males of T. perditor produce the ester, methyl 2E, 4Z, 6Z-decatrienoate. Whereas, the stink bug, P. guildinii has as sexual pheromone, the sesquiterpene beta-sesqui phellandrene, and the stink bug T. limbativentris produces as sex attractant the zingiberenol. In this review we discuss the advances obtained on the behaviour and identification of sex and defensive compound of stink bugs from Brazilian crops and the application of this knowledge to manage the stink bugs. (author)

  6. Aspectos ecológicos da tripanossomíase americana: XIV - Persistência e potencial de domiciliação de populações triatomínicas silvestres em região de intensa atividade agropecuária Ecological aspects of South American tripanosomiasis: XIV - Persistence and domiciliation potential of sylvatic triatominae populations in an intensive agricultural and cattle breeding region

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1979-06-01

    Full Text Available São apresentados os resultados de observações sobre populações triatomínicas extradomiciliares em região de intensa atividade agropecuária. Os restos de vegetação primitiva, embora reduzidos a menos de 8,0%, mostraram-se suficientes para manter essas populações. Pelo menos para Triatoma sordida, a destruição progressiva parece favorecer sua sobrevivência, graças à multiplicação de ecótopos preferidos por esse triatomíneo. Tanto essa espécie como Panstrongylus megistus e Rhodnius neglectus mostraram-se aptos à colonização em ecótopos artificiais representados por galinheiros experimentais.The results of observation of sylvatic triatominae population in a region of intensive agricultural and cattle breeding activity are reported. Important environmental changes had occurred in the area, including destruction of the primitive vegetation and intensive use of pesticides. Nevertheless, these modifications apparently did not affect the survival of Triatominae, since they were found in the remaining vegetation. Moreover, this destruction seems to have favored, to some extent, survival of Triatoma sordida by increasing the available ecotopes. This species, as well as Panstrongylus megistus and Rhodnius neglectus, showed enough ecological valence to colonize experimental fowes houses, used as artificial ecotopes.

  7. Levantamento da fauna de Triatominae (Hemiptera: Reduviidae em ambiente domiciliar e infecção natural por Trypanosomatidae no Estado de Mato Grosso do Sul Survey of Triatominae (Hemiptera: Reduviidae fauna in domestic environments and natural infection by Trypanosomatidae in the State of Mato Grosso do Sul

    Directory of Open Access Journals (Sweden)

    Paulo Silva de Almeida

    2008-08-01

    Full Text Available Entre 2000 a 2004, foi realizado levantamento da fauna de Triatominae (Hemiptera: Reduviidae e exame de infecção natural por Trypanosomatidae, no Estado de Mato Grosso do Sul. Um total de 13.671 espécimes foram capturados. Na análise faunística das espécies capturadas, Triatoma sordida foi caracterizada como muito abundante, muito freqüente, constante e dominante. Os índices de infecção natural para Trypanosoma cruzi apresentaram os valores de 3,2% para Panstrongylus geniculatus, 0,6% para Rhodnius neglectus e 0,1% para Triatoma sordida, apesar do Estado de Mato Grosso do Sul apresentar-se livre da transmissão vetorial endêmica.Between 2000 and 2004, a survey of Triatominae fauna (Hemiptera: Reduviidae and examination of natural infection caused by Trypanosomatidae in the State of Mato Grosso do Sul, Brazil, was conducted. A total of 13,671 specimens were collected. Through fauna analysis on the insects that were caught, Triatoma sordida was characterized as very abundant, very frequent, constant and dominant. The rates of natural infection with Trypanosoma cruzi were 3.2% for Panstrongylus geniculatus, 0.6% for Rhodnius neglectus and 0.1% for Triatoma sordida. Nevertheless, the State of Mato Grosso do Sul is free from endemic vector transmission.

  8. Epidemiologia de um caso de doença de Chagas na Ilha do Mosqueiro - Pará

    Directory of Open Access Journals (Sweden)

    Adelson A.A. de Souza

    1988-12-01

    Full Text Available Os autores apresentam os resultados do estudo epidemiológico de um caso autóctone da fase aguda da doença de Chagas na ilha do Mosqueiro, Estado do Pará, aproximadamente 75km da capital, Belém. 0 caso já havia sido objeto de uma publicação anterior. Agora são apresentadas informações epidemiológicas. Nas proximidades da casa do paciente foram capturados em duas palmeiras de Inajá ('Maximilian regi ay e em uma de Mucajá (Acrocomia sclerocarpia 114 triatomíneos: Rhodnius pictipes, R. robustus, Panstrongylus lignarius, P. geniculatus e Microtriatoma trinidadensis, com tripanossomas em 31 deles. Na casa do paciente foram encontrados exemplares de Rhodnius pictipes, infectados com formas metacíclicas do Trypanosoma cruzi. Em 14 marsupiais, capturados na localidade, haviam 3 infectados com organismos semelhantes ao T. cruzi. A eletroforese dos isoenzimas nos tripanossomas isolados do paciente, de R. pictipes e de Didelphis marsupialis os classificou como zimodema 1. Os autores concluem que a doença de Chagas do paciente teve origem silvestre.

  9. Epidemiologia de um caso de doença de Chagas na Ilha do Mosqueiro - Pará

    Directory of Open Access Journals (Sweden)

    Adelson A.A. de Souza

    1988-12-01

    Full Text Available Os autores apresentam os resultados do estudo epidemiológico de um caso autóctone da fase aguda da doença de Chagas na ilha do Mosqueiro, Estado do Pará, aproximadamente 75km da capital, Belém. 0 caso já havia sido objeto de uma publicação anterior. Agora são apresentadas informações epidemiológicas. Nas proximidades da casa do paciente foram capturados em duas palmeiras de Inajá ('Maximilian regi ay e em uma de Mucajá (Acrocomia sclerocarpia 114 triatomíneos: Rhodnius pictipes, R. robustus, Panstrongylus lignarius, P. geniculatus e Microtriatoma trinidadensis, com tripanossomas em 31 deles. Na casa do paciente foram encontrados exemplares de Rhodnius pictipes, infectados com formas metacíclicas do Trypanosoma cruzi. Em 14 marsupiais, capturados na localidade, haviam 3 infectados com organismos semelhantes ao T. cruzi. A eletroforese dos isoenzimas nos tripanossomas isolados do paciente, de R. pictipes e de Didelphis marsupialis os classificou como zimodema 1. Os autores concluem que a doença de Chagas do paciente teve origem silvestre.The authors present the results of an epidemiological study relating to a case of acute Chagas' disease acquired in the island of Mosqueiro, State of Para, approximately 75 km from the capital Belem. The patient has been the object of a previous publication but now epidemiological information is reported. Near the house of the patient in two Inaja palm trees (Maximilian regia and one Mucaja palm (Acrocomia sclerocarpia 114 triatomine bugs were captured of the following species: Rhodnius pictipes, R. robustus, Panstrongylus lignarius, P. geniculatus and Microtriatoma trinidadensis. Trypanosomes were found in 31 bugs. In the house of the patient specimens of R. pictipes were captured infected with metacyclic forms óf Trypanosoma cruzi. In 14 marsupials captured in the locality three had infections with cruzi like trypanosomes. Enzyme electrophoresis of the trypanosomes isolated from the patient, R

  10. The Cementation of Boron to Steels by the Method of Electrolytic Deposition; Cementation Electrolytique d'Aciers par le Bore; Tsementirovanie bora v stali putem ehlektroliticheskogo osazhdeniya; Cementacion de Aceros con Boro por Deposito Electrolitico

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, M. [Tokyo Institute of Technology (Japan)

    1964-06-15

    aceros al carbono, aceros inoxidables, acero de elevado contenido de cromo, etc.; todos ellos dan resultados satisfactorios. (author) [Russian] Privoditsja metod izgotovlenija upravljajushhego sterzhnja s cementirovaniem bora. Jetot process osushhestvljaetsja posredstvom jelektroliza rasplavlennogo tetrabornokislogo natrija pri temperature okolo 900 Degree-Sign S . Obrabatyvaemyj stal'noj sterzhen' sluzhit katodom, v k a chestve anoda ispol'zuetsja grafitovyj jelektrod. V processe jelektroliza bor osazhdaetsja na stal'noj sterzhen' i diffundiruet v sta l'. Pri podhodjashhih uslovijah jelektroliza legko udaetsja poluchit' stal'noj sterzhen', soderzhashhij po 20% bora. Issledovalis' sledujushhie tipy stali: uglerodistaja, nerzhavejushhie, hromistaja i t.d. , vo vseh sluchajah byli polucheny polozhitel'nye rezul'taty. (author)

  11. The importance of the opossum (Didelphis albiventris as a reservoir for Trypanosoma cruzi in Bambuí, Minas Gerais state

    Directory of Open Access Journals (Sweden)

    Alexandre José Fernandes

    1991-03-01

    Full Text Available In a survey realized on the sylvatic and peridomestic environment at Bambuí county, Minas Gerais State, 44 (37.9% out of 116 opossums (Didelphis albiventris captured were found to be naturally infected with Trypanosoma cruzi. One handred and forty three parasite samples were obtanied from 43 infected opossums using simultaneously hemoculture, xenodiagnosis (Triatoma infestans, Panstrongylus megistus and Rhodnius neglectus and examination of anal glands contents. The parasite samples were characterized according to six isoenzyme patterns. All samples, independently of the method of isolation, presented an isoenzyme pattern similar to the standard T. cruzi Z1, showing that either xenodiagnosis or hemoculture can used without selecting parasite subpopulation from naturally infected opossums. Preveous isoenzyme patterns reported for human T.cruzi isolates from same region were completely different. This isoenzyme dissimilarity between sylvatic and domiciliar environments suggests the existence of two independent T. cruzi transmission cycles in Bambuí. The epidemiological implicatinos of these results are discussed.

  12. On the possibility of autochthonous Chagas disease in Roraima, Amazon region, Brazil, 2000-2001 Sobre a possibilidade da ocorrência de doença de Chagas autóctone em Roraima, Amazônia brasileira, 2000-2001

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    José Francisco Luitgards-Moura

    2005-02-01

    Full Text Available Chagas disease has been almost entirely eradicated from the arid zones in Central and Northeastern Brazil where rare or no autochthonous cases have been reported. However, in the last 10 years the disease has increasingly been registered in the Amazon Region. Aiming to investigate the possibility of the occurrence of autochthonous cycle of Chagas disease in Roraima, triatomine collections, vectorial susceptibility studies (this one to be shown elsewhere, parasitological and serological analyses were conducted in three agricultural settlement areas (Rorainópolis, Passarão Project and Ilha Community. Blood-donor candidates were also investigated. This is the first epidemiological survey on Chagas disease conducted in agricultural settlements in Roraima. Triatomine species found were Triatoma maculata, Rhodnius pictipes, Rhodnius robustus and Panstrongylus geniculatus. Trypanosoma cruzi detection analyses included xenodiagnosis, indirect immunofluorescence, indirect hemaglutination, ELISA and kinetoplast PCR amplification. Natural triatomine infection was not found in intestinal contents. Twenty-five adult settlers (1.4% out of 1821, all > 15 year-old, 20 migrants presented anti-T. cruzi antibodies. Two migrant settlers (from Minas Gerais and Maranhão tested positive for more than two serological tests, besides either being positive for xenodiagnosis or PCR. Results show that Chagas disease is not endemic in the areas studied. However, all elements of the transmission cycle are present, demanding for an adequate and continuous vigilance.A doença de Chagas foi quase inteiramente erradicada das zonas áridas do Brasil Central e Nordeste, onde ciclos autóctones de transmissão praticamente inexistem. Contudo, na última década a doença vem sendo registrada na Região Amazônica. Objetivando investigar a possibilidade da ocorrência de ciclos autóctones de transmissão em áreas de colonização agrícola no Estado de Roraima, foram realizadas

  13. Absence of domestic triatomine colonies in an area of the coastal region of Ecuador where Chagas disease is endemic

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    Mario J Grijalva

    2010-08-01

    Full Text Available Rhodnius ecuadoriensis is considered the second most important vector of Chagas disease in Ecuador. It is distributed across six of the 24 provinces and occupies intradomiciliary, peridomiciliary and sylvatic habitats. This study was conducted in six communities within the coastal province of Guayas. Triatomine searches were conducted in domestic and peridomestic habitats and bird nests using manual searches, live-bait traps and sensor boxes. Synantrhopic mammals were captured in the domestic and peridomestic habitats. Household searches (n = 429 and randomly placed sensor boxes (n = 360 produced no live triatomine adults or nymphs. In contrast, eight nymphs were found in two out of six searched Campylorhynchus fasciatus (Troglodytidae nests. Finally, Trypanosoma cruzi DNA was amplified from the blood of 10% of the 115 examined mammals. Environmental changes in land use (intensive rice farming, mosquito control interventions and lack of intradomestic adaptation are suggested among the possible reasons for the lack of domestic triatomine colonies.

  14. Correlação entre a positividade do xenodiagnóstico artificial e a quantidade de sangue e triatomíneos utilizados no exame, em pacientes chagásicos crônicos

    OpenAIRE

    Franco,Yara Bandeira Azevedo; Silva,Ionizete Garcia da; Rassi,Anis; Rocha,Alessandra Carla Rodrigues Galvão; Silva,Heloisa Helena Garcia da; Rassi,Gustavo Gabriel

    2002-01-01

    Estudou-se a correlação entre a positividade do xenodiagnóstico artificial e a quantidade utilizada de sangue e de triatomíneos, em 200 pacientes na fase crônica da doença de Chagas. Colheram-se 10 ou 40ml de sangue através de tubos a vácuo, heparinizados com 20,4UI, sendo realizado com 60 e 360 triatomíneos, respectivamente. Usou-se Dipetalogaster maximus, Triatoma infestans, Triatoma vitticeps e Rhodnius neglectus, nos estádios 1°, 3°, 3° e 4°, respectivamente. A coproscopia dos triatomíneo...

  15. [Geographical distribution and indicators entomologic of sinantropic triatomines captured in the State of Goiás].

    Science.gov (United States)

    de Oliveira, Antônio Wilson Soares; da Silva, Ionizete Garcia

    2007-01-01

    The geographic distribution of triatomines in Goiás and entomological indicators in the home environment are presented: home infestation, home triatomine density and vector infection by Trypanosoma cruzi. The indicators studied were from triatomines captured inside and outside homes in 201 municipalities in the State of Goiás, Brazil, between 2000 and 2003. A total of 249,868 home units were investigated and 51,570 triatomines were captured, and 335 specimens were found to be infected with Trypanosoma cruzi. Infestation outside the home was significantly greater than infestation inside the home for the species Triatoma sordida, followed by Panstrongylus megistus. The contrary was observed with the species Rhodnius neglectus, Panstrongylus geniculatus and Triatoma pseudomaculata (p<0.018). There was no significant difference between infestations inside and outside the home for the species Panstrongylus diasi, Triatoma costalimai and Triatoma williami. Only one specimen of Triatoma infestans was captured in the year 2000.

  16. Enzootic transmission of Trypanosoma cruzi and T. rangeli in the Federal District of Brazil Transmissão enzoótica de Trypanosoma cruzi e T. rangeli no Distrito Federal, Brasil

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    Rodrigo Gurgel-Gonçalves

    2004-04-01

    Full Text Available The Federal District of Brazil (DF lies within the Cerrado biome, where open shrubland (savannas is interspersed with riverside gallery forests and permanent swamps (veredas. Trypanosoma cruzi-infected native triatomines occur in the area, but the enzootic transmission of trypanosomatids remains poorly characterized. A parasitological survey involving sylvatic triatomines (166 Rhodnius neglectus collected from Mauritia flexuosa palms and small mammals (98 marsupials and 70 rodents, totaling 18 species was conducted in 18 sites (mainly gallery forests and veredas of the DF. Parasites were isolated, morphologically identified, and characterized by PCR of nuclear (mini-exon gene and kinetoplast DNA (kDNA. Six R. neglectus, seven Didelphis albiventris and one Akodon cursor were infected by trypanosomes; wild reservoir infection is documented for the first time in the DF. kDNA PCR detected T. cruzi in five R. neglectus and mini-exon gene PCR revealed T. cruzi I in isolates from D. albiventris. Parasites infecting one bug yielded T. rangeli KP1+ kDNA amplicons. In spite of the occurrence of T. cruzi-infected D. albiventris (an important wild and peridomestic reservoir and R. neglectus (a secondary vector displaying synanthropic behavior, a low-risk of human Chagas disease transmission could be expected in the DF, considering the low prevalence infection recorded in this work. The detection of T. rangeli KP1+ associated with R. neglectus in the DF widens the known range of this parasite in Brazil and reinforces the hypothesis of adaptation of T. rangeli populations (KP1+ and KP1- to distinct evolutionary Rhodnius lineages.O Distrito Federal (DF do Brasil está localizado no bioma Cerrado, um complexo de fisionomias savânicas incluindo matas de galeria e campos úmidos permanentes (veredas. Triatomíneos silvestres infectados por Trypanosoma cruzi ocorrem na área, mas a transmissão enzoótica de tripanossomatídeos permanece insuficientemente

  17. Contribuição ao estudo da distribuição geográfica de triatomíneos no estado do Piauí

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    Paulo Zábulon de Figueirêdo

    1975-08-01

    Full Text Available Os autores apresentam a atual distribuição geográfica dos triatomineos no Estado do Piauí. Dos 28 municípios trabalhados em três diferentes regiões naturais, 18 apresentaram capturas positivas, com as seguintes espécies: Triatoma brasiliensis, T. maculata, T. sórdida, Rhodnius pictepes, R. neglectus e Panstrongylus geniculatus. Das espécies citadas, o T. brasiliensis foi a mais freqüente e de maior distribuição. Os autores admitem ser essa espécie a mais importante transmissora da Doença de Chagas, no Estado. Chamam a atenção, ainda, para o papel que as espécies de R. pictepes e R. neglectus possam desempenhar na manutenção do ciclo silvestre do Trypanosoma cruzi, ao lado do P. geniculatus.

  18. Triatominae et Cactaceae : un risque pour la transmission de la Trypanosomose américaine dans le péridomicile (nord-est du Brésil

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    Emperaire L.

    2006-06-01

    Full Text Available Les observations de terrain réalisées dans le nord-est du Brésil ont montré la fréquente association, dans l’espace péridomiciliaire, entre un cactus, le Cereus jamacaru, la présence de nids dans ses branches et celle de Rhodnius neglectus et de Triatoma pseudomaculata, espèces vectrices du parasite Trypanosoma cruzi, agent de la maladie de Chagas. L’analyse des variables architecturales de cette Cactaceae montre que la présence de nids, et donc d’insectes, est inféodée aux pratiques traditionnelles de gestion de ce cactus. Cette étude souligne l’intérêt d’une approche intégrée de l’écologie des Triatominae pour l’identification des variables indicatrices de risque.

  19. Trapping Triatominae in Silvatic Habitats

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    Noireau François

    2002-01-01

    Full Text Available Large-scale trials of a trapping system designed to collect silvatic Triatominae are reported. Live-baited adhesive traps were tested in various ecosystems and different triatomine habitats (arboreal and terrestrial. The trials were always successful, with a rate of positive habitats generally over 20% and reaching 48.4% for palm trees of the Amazon basin. Eleven species of Triatominae belonging to the three genera of public health importance (Triatoma, Rhodnius and Panstrongylus were captured. This trapping system provides an effective way to detect the presence of triatomines in terrestrial and arboreal silvatic habitats and represents a promising tool for ecological studies. Various lines of research are contemplated to improve the performance of this trapping system.

  20. Trypanosoma cruzi I genotypes in different geographic regions and transmission cycles based on a microsatellite motif of the intergenic spacer of spliced leader genes✯

    Science.gov (United States)

    Cura, Carolina I.; Mejía-Jaramillo, Ana M.; Duffy, Tomás; Burgos, Juan M.; Rodriguero, Marcela; Cardinal, Marta V.; Kjos, Sonia; Gurgel-Gonçalves, Rodrigo; Blanchet, Denis; De Pablos, Luis M.; Tomasini, Nicolás; Silva, Alex Da; Russomando, Graciela; Cuba Cuba, Cesar A.; Aznar, Christine; Abate, Teresa; Levin, Mariano J.; Osuna, Antonio; Gürtler, Ricardo E.; Diosque, Patricio; Solari, Aldo; Triana-Chávez, Omar; Schijman, Alejandro G.

    2011-01-01

    The intergenic region of spliced-leader (SL-IR) genes from 105 Trypanosoma cruzi I (Tc I) infected biological samples, culture isolates and stocks from 11 endemic countries, from Argentina to the USA were characterised, allowing identification of 76 genotypes with 54 polymorphic sites from 123 aligned sequences. On the basis of the microsatellite motif proposed by Herrera et al. (2007) to define four haplotypes in Colombia, we could classify these genotypes into four distinct Tc I SL-IR groups, three corresponding to the former haplotypes Ia (11 genotypes), Ib (11 genotypes) and Id (35 genotypes); and one novel group, Ie (19 genotypes). Genotypes harboring the Tc Ic motif were not detected in our study. Tc Ia was associated with domestic cycles in southern and northern South America and sylvatic cycles in Central and North America. Tc Ib was found in all transmission cycles from Colombia. Tc Id was identified in all transmission cycles from Argentina and Colombia, including Chagas cardiomyopathy patients, sylvatic Brazilian samples and human cases from French Guiana, Panama and Venezuela. Tc Ie gathered five samples from domestic Triatoma infestans from northern Argentina, nine samples from wild Mepraia spinolai and Mepraia gajardoi and two chagasic patients from Chile and one from a Bolivian patient with chagasic reactivation. Mixed infections by Tc Ia + Tc Id, Tc Ia + Tc Ie and Tc Id + Tc Ie were detected in vector faeces and isolates from human and vector samples. In addition, Tc Ia and Tc Id were identified in different tissues from a heart transplanted Chagas cardiomyopathy patient with reactivation, denoting histotropism. Trypanosoma cruzi I SL-IR genotypes from parasites infecting Triatoma gerstaeckeri and Didelphis virginiana from USA, T. infestans from Paraguay, Rhodnius nasutus and Rhodnius neglectus from Brazil and M. spinolai and M. gajardoi from Chile are to our knowledge described for the first time. PMID:20670628

  1. Distribuição geográfica e indicadores entomológicos de triatomíneos sinantrópicos capturados no Estado de Goiás Geographical distribution and indicators entomologic of sinantropic triatomines captured in the State of Goiás

    Directory of Open Access Journals (Sweden)

    Antônio Wilson Soares de Oliveira

    2007-04-01

    Full Text Available Apresenta-se a distribuição geográfica de triatomíneos em Goiás e indicadores entomológicos no ambiente domiciliar: infestação domiciliar, densidade triatomínica domiciliar e infecção vetorial pelo Trypanosoma cruzi. Os indicadores estudados foram de triatomíneos capturados no intra e peridomicílio, em 201 municípios, no Estado de Goiás, Brasil, no período entre 2000 e 2003. Foram investigadas 249.868 unidades domiciliares e capturados 51.570 triatomíneos, com 335 espécimes infectados com Trypanosoma cruzi. A infestação peridomiciliar foi significativamente maior do que a intradomiciliar na espécie Triatoma sordida, seguida de Panstrongylus megistus. O inverso ocorreu nas espécies Rhodnius neglectus, Panstrongylus geniculatus e Triatoma pseudomaculata (pThe geographic distribution of triatomines in Goiás and entomological indicators in the home environment are presented: home infestation, home triatomine density and vector infection by Trypanosoma cruzi. The indicators studied were from triatomines captured inside and outside homes in 201 municipalities in the State of Goiás, Brazil, between 2000 and 2003. A total of 249,868 home units were investigated and 51,570 triatomines were captured, and 335 specimens were found to be infected with Trypanosoma cruzi. Infestation outside the home was significantly greater than infestation inside the home for the species Triatoma sordida, followed by Panstrongylus megistus. The contrary was observed with the species Rhodnius neglectus, Panstrongylus geniculatus and Triatoma pseudomaculata (p<0.018. There was no significant difference between infestations inside and outside the home for the species Panstrongylus diasi, Triatoma costalimai and Triatoma williami. Only one specimen of Triatoma infestans was captured in the year 2000.

  2. Cultivation-independent methods reveal differences among bacterial gut microbiota in triatomine vectors of Chagas disease.

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    Fabio Faria da Mota

    Full Text Available BACKGROUND: Chagas disease is a trypanosomiasis whose agent is the protozoan parasite Trypanosoma cruzi, which is transmitted to humans by hematophagous bugs known as triatomines. Even though insecticide treatments allow effective control of these bugs in most Latin American countries where Chagas disease is endemic, the disease still affects a large proportion of the population of South America. The features of the disease in humans have been extensively studied, and the genome of the parasite has been sequenced, but no effective drug is yet available to treat Chagas disease. The digestive tract of the insect vectors in which T. cruzi develops has been much less well investigated than blood from its human hosts and constitutes a dynamic environment with very different conditions. Thus, we investigated the composition of the predominant bacterial species of the microbiota in insect vectors from Rhodnius, Triatoma, Panstrongylus and Dipetalogaster genera. METHODOLOGY/PRINCIPAL FINDINGS: Microbiota of triatomine guts were investigated using cultivation-independent methods, i.e., phylogenetic analysis of 16s rDNA using denaturing gradient gel electrophoresis (DGGE and cloned-based sequencing. The Chao index showed that the diversity of bacterial species in triatomine guts is low, comprising fewer than 20 predominant species, and that these species vary between insect species. The analyses showed that Serratia predominates in Rhodnius, Arsenophonus predominates in Triatoma and Panstrongylus, while Candidatus Rohrkolberia predominates in Dipetalogaster. CONCLUSIONS/SIGNIFICANCE: The microbiota of triatomine guts represents one of the factors that may interfere with T. cruzi transmission and virulence in humans. The knowledge of its composition according to insect species is important for designing measures of biological control for T. cruzi. We found that the predominant species of the bacterial microbiota in triatomines form a group of low

  3. The ecotopes and evolution of triatomine bugs (triatominae and their associated trypanosomes

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    Gaunt Michael

    2000-01-01

    Full Text Available Triatomine bug species such as Microtriatoma trinidadensis, Eratyrus mucronatus, Belminus herreri, Panstrongylus lignarius, and Triatoma tibiamaculata are exquisitely adapted to specialist niches. This suggests a long evolutionary history, as well as the recent dramatic spread a few eclectic, domiciliated triatomine species. Virtually all species of the genus Rhodnius are primarily associated with palms. The genus Panstrongylus is predominantly associated with burrows and tree cavities and the genus Triatoma with terrestrial rocky habitats or rodent burrows. Two major sub-divisions have been defined within the species Trypanosoma cruzi, as T. cruzi 1 (Z1 and T. cruzi 2 (Z2. The affinities of a third group (Z3 are uncertain. Host and habitat associations lead us to propose that T. cruzi 1 (Z1 has evolved in an arboreal, palm tree habitat with the triatomine tribe Rhodniini, in association with the opossum Didelphis. Similarly we propose that T. cruzi (Z2 and Z3 evolved in a terrestrial habitat in burrows and in rocky locations with the triatomine tribe Triatomini, in association with edentates, and/or possibly ground dwelling marsupials. Both sub-divisions of T. cruzi may have been contemporary in South America up to 65 million years ago. Alternatively, T. cruzi 2 (Z2 may have evolved more recently from T. cruzi 1 (Z1 by host transfers into rodents, edentates, and primates. We have constructed a molecular phylogeny of haematophagous vectors, including triatomine bugs, which suggests that faecal transmission of trypanosomes may be the ancestral route. A molecular clock phylogeny suggests that Rhodnius and Triatoma diverged before the arrival, about 40 million years ago, of bats and rodents into South America.

  4. Drivers of house invasion by sylvatic Chagas disease vectors in the Amazon-Cerrado transition: A multi-year, state-wide assessment of municipality-aggregated surveillance data.

    Science.gov (United States)

    Brito, Raíssa N; Gorla, David E; Diotaiuti, Liléia; Gomes, Anália C F; Souza, Rita C M; Abad-Franch, Fernando

    2017-11-01

    Insecticide spraying efficiently controls house infestation by triatomine bugs, the vectors of Trypanosoma cruzi. The strategy, however, is ineffective against sylvatic triatomines, which can transmit Chagas disease by invading (without colonizing) man-made structures. Despite growing awareness of the relevance of these transmission dynamics, the drivers of house invasion by sylvatic triatomines remain poorly understood. About 12,000 sylvatic triatomines were caught during routine surveillance in houses of Tocantins state, Brazil, in 2005-2013. Using negative binomial regression, information-theoretic model evaluation/averaging, and external model validation, we investigated the effects of regional (Amazon/Cerrado), landscape (preservation/disturbance), and climate covariates (temperature, rainfall) on the municipality-aggregated numbers of house-invading Rhodnius pictipes, R. robustus, R. neglectus, and Panstrongylus geniculatus. House invasion by R. pictipes and R. robustus was overall more frequent in the Amazon biome, tended to increase in municipalities with more well-preserved land, and decreased in rainier municipalities. Across species, invasion decreased with higher landscape-disturbance levels and in hotter-day municipalities. Invasion by R. neglectus and P. geniculatus increased somewhat with more land at intermediate disturbance and peaked in average-rainfall municipalities. Temperature effects were more pronounced on P. geniculatus than on Rhodnius spp. We report widespread, frequent house invasion by sylvatic triatomines in the Amazon-Cerrado transition. Our analyses indicate that readily available environmental metrics may help predict the risk of contact between sylvatic triatomines and humans at coarse geographic scales, and hint at specific hypotheses about climate and deforestation effects on those vectors-with some taxon-specific responses and some seemingly general trends. Thus, our focal species appear to be quite sensitive to higher

  5. Cultivation-independent methods reveal differences among bacterial gut microbiota in triatomine vectors of Chagas disease.

    Science.gov (United States)

    da Mota, Fabio Faria; Marinho, Lourena Pinheiro; Moreira, Carlos José de Carvalho; Lima, Marli Maria; Mello, Cícero Brasileiro; Garcia, Eloi Souza; Carels, Nicolas; Azambuja, Patricia

    2012-01-01

    Chagas disease is a trypanosomiasis whose agent is the protozoan parasite Trypanosoma cruzi, which is transmitted to humans by hematophagous bugs known as triatomines. Even though insecticide treatments allow effective control of these bugs in most Latin American countries where Chagas disease is endemic, the disease still affects a large proportion of the population of South America. The features of the disease in humans have been extensively studied, and the genome of the parasite has been sequenced, but no effective drug is yet available to treat Chagas disease. The digestive tract of the insect vectors in which T. cruzi develops has been much less well investigated than blood from its human hosts and constitutes a dynamic environment with very different conditions. Thus, we investigated the composition of the predominant bacterial species of the microbiota in insect vectors from Rhodnius, Triatoma, Panstrongylus and Dipetalogaster genera. Microbiota of triatomine guts were investigated using cultivation-independent methods, i.e., phylogenetic analysis of 16s rDNA using denaturing gradient gel electrophoresis (DGGE) and cloned-based sequencing. The Chao index showed that the diversity of bacterial species in triatomine guts is low, comprising fewer than 20 predominant species, and that these species vary between insect species. The analyses showed that Serratia predominates in Rhodnius, Arsenophonus predominates in Triatoma and Panstrongylus, while Candidatus Rohrkolberia predominates in Dipetalogaster. The microbiota of triatomine guts represents one of the factors that may interfere with T. cruzi transmission and virulence in humans. The knowledge of its composition according to insect species is important for designing measures of biological control for T. cruzi. We found that the predominant species of the bacterial microbiota in triatomines form a group of low complexity whose structure differs according to the vector genus.

  6. Detekce malware na počítačové síti

    OpenAIRE

    Šolar, Tomáš

    2008-01-01

    V současné době se stal firewall již nedostatečným prostředkem pro ochranu počítačových sítí. Kvůli stále se zvyšujícím hrozbám pocházejícím z internetu třeba v podobě malwaru či útoků hackerů se vyvinuly systémy detekce (IDS) a prevence (IPS) narušení. Tyto systémy fungují jako další stupeň zabezpečení počítačových sítí, přičemž IDS systémy mají jako hlavní funkčnost především detekci, kdežto IPS systémy jsou schopné i na napadení zareagovat. Cílem této práce je provádět detekci na modelovém...

  7. Danish firms visit CERN

    CERN Multimedia

    FP Department

    2011-01-01

    30 – 31 JANUARY 2012 09:00 to 17:00 Monday 30 January 09:00 to 17:00 Tuesday 31 January Individual interviews will take place in technicians’ offices. The firms will contact relevant users/technicians but any user wishing to make contact with a particular firm is welcome to use the contact details available from the secretariat of their department or from the GS Department web page. List of Companies: · Axcon APS · BB Electronics A/S · B.Rustfrit Stal A/S · CIM Industrial Systems A/S · Danfysik A/S · Develco A/S · Eletronic A/S · GPV Group · Innoware A/S · JLI Vision A/S · NECAS A/S· NKT Cables A/S · Noliac A/S · Prodan A/S · Röttger’s Vaerktoj A/S · Vengcon APS For further information please contact Claudia Bruggmann Furlan  GS-IS-LS 73312 or Caroline Laignel GS-DI 73722.

  8. Visit of Danish firms at CERN

    CERN Multimedia

    GS Department

    2012-01-01

    30 – 31 JANUARY 2012 09h00 to 17h00 Monday 30 January 09h00 to 17h00 Tuesday 31 January Individual interviews will take place in technicians’ offices. The firms will contact relevant users/technicians but any user wishing to make contact with a particular firm is welcome to use the contact details which are available from each secretariat of department or from the GS Department web pages at the following URL http://gs-dep.web.cern.ch/en/content/Industrial-Exhibitions List of Companies: Axcon APS BB Electronics A/S B.Rustfrit Stal A/S CIM Industrial Systems A/S Danfysik A/S Develco A/S Eletronic A/S GPV Group Innoware A/S JLI Vision A/S NECAS A/S NKT Cables A/S Noliac A/S Röttger’s Vaerktoj A/S   For further information please contact Claudia Bruggmann Furlan  GS-IS-LS 73312 or Caroline Laignel GS-DI 73722.

  9. Residual Acute Toxicity of Some Modern Insecticides Toward Two Mirid Predators of Tomato Pests.

    Science.gov (United States)

    Wanumen, Andrea C; Carvalho, Geraldo A; Medina, Pilar; Viñuela, Elisa; Adán, Ángeles

    2016-03-31

    The successful integration of chemical and biological control strategies for crop pests depends on a thorough evaluation of the effects of pesticides on the natural enemies of pests. A case-by-case review is difficult to achieve because of the many combinations of pests, natural enemies, and crops that need to be tested. Within this framework, we tested and compared seven insecticides representative of four different modes of action (MoAs) groups on closely related predators (Miridae): flubendiamide, spirotetramat, metaflumizone, and sulfoxaflor onNesidiocoris tenuisReuter and flubendiamide, spiromesifen, indoxacarb, and imidacloprid onMacrolophus basicornis(Stal). We follow the standardized methodology of the International Organization for Biological Control, a sequential testing exposure scheme. The lethal effect of each insecticide was evaluated in adults after three days of contact with treated surfaces in the laboratory, extended laboratory, and semifield tests (inert substrate, tomato leaves, and tomato plant as the treated surface, respectively). Flubendiamide, spiromesifen, and spirotetramat were classified as harmless (class 1), metaflumizone was slightly harmful (class 2) but persistent, indoxacarb was harmless (class 1), and sulfoxaflor and imidacloprid were toxic (class 4) and exhibited a long residual activity. Our results suggest similarities in the acute toxicities of insecticides from the same MoA group on related species of natural enemies. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Infestation of froghopper nymphs changes the amounts of total phenolics in sugarcane

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    Silva Rafael José Navas da

    2005-01-01

    Full Text Available The increased rate of sugarcane harvest without previous burn has provided a very favorable environment to the froghopper Mahanarva fimbriolata (Stal, 1854, with high moisture and low temperature variation. Few works have studied the response of sugarcane to this pest, so little is known about resistant cultivars. Plant phenolics are widely studied compounds because of their known antiherbivore effect. This research aims to determine if the attack of M. fimbriolata nymphs stimulates the accumulation of total phenolics in sugarcane. The experiment was carried out in greenhouse and arranged in completely randomized design, in a 3 X 2 X 4 factorial with three replications. Second instar nymphs of M. fimbriolata were infested at the following rates: control, 2-4 and 4-8 nymphs per pot (first-second infestations, respectively. Pots were covered with nylon net and monitored daily to isolate the effect of leaf sucking adults. Leaf and root samples were collected and kept frozen in liquid nitrogen until analyses. Infested plants showed higher levels of phenolics in both root and leaf tissues. In roots, the cultivar SP80-1816 accumulated more phenolic compounds in response to the infestation of M. fimbriolata. On the other hand, higher levels were found in leaves and roots of control plants of SP86-42, which might be an indication of a non-preference mechanism. The increase of total phenolics in sugarcane infested with root-sucking froghopper nymphs does not seem to be useful to detect the resistance to this pest.

  11. Farmers' Perceptions of and Adaptations to Changing Climate in the Melamchi Valley of Nepal

    Directory of Open Access Journals (Sweden)

    Nani Maiya Sujakhu

    2016-02-01

    Full Text Available Knowledge of farmers’ perceptions of and adaptations to climate change is important to inform policies addressing the risk of climate change to farmers. This case study explored those issues in the Melamchi Valley of Nepal through a survey of 365 households and focus group discussions in 6 communities using a Community-Based Risk Screening Tool–Adaptation and Livelihoods (CRiSTAL. Analysis of climate trends in the study area for 1979–2009 showed that mean annual temperatures rose by 1.02°C and the frequency of drought increased measurably after 2003. Farmers reported increases in crop pests, hailstorms, landslides, floods, thunderstorms, and erratic precipitation as climate-related hazards affecting agriculture. They responded in a variety of ways including changing farming practices, selling livestock, milk, and eggs, and engaging in daily wage labor and seasonal labor migration. With more efficient support and planning, some of these measures could be adjusted to better meet current and future risks from climate change.

  12. Nové generace sídel

    OpenAIRE

    Zhuravlyova, Yelena

    2014-01-01

    Každé velké město se postupem času dostává do těžko řešitelných problémů: přelidnění, dopravní zácpy, zhoršení ekologické situace. Přechod od průmyslové k informační fázi růstu proběhl v některých zemích rychleji, než se podařilo přetvořit infrastrukturu. Například v Asii je prakticky nemožné změnit situaci tradičními způsoby. Proto se objevuje nový trend - výstavba nových měst prakticky na zelené louce. Lisabon se stal v roce 2010 místem, kde byl prezentován nový, tentokrát „portugalský“ pro...

  13. Molecular cloning and expression profile of an ATP-binding cassette (ABC) transporter gene from the hemipteran insect Nilaparvata lugens.

    Science.gov (United States)

    Zha, W J; Li, S H; Zhou, L; Chen, Z J; Liu, K; Yang, G C; Hu, G; He, G C; You, A Q

    2015-03-30

    The ATP-binding cassette (ABC) transporters belong to a large superfamily of proteins that have important physiological functions in all living organisms. In insects, ABC transporters have important functions in the transport of molecules, and are also involved in insecticide resistance, metabolism, and development. In this study, the Nilaparvata lugens Stal (Hemiptera: Delphacidae) ABCG (NlABCG) gene was identified and characterized. The complete mRNA sequence of NlABCG was 2608-bp long, with an open reading frame of 2064 bp encoding a protein comprised of 687 amino acids. The conserved regions include three N-glycosylation and 34 phosphorylation sites, as well as seven transmembrane domains. The amino acid identity with the closely related species Acyrthosiphon pisum was 42.8%. Developmental expression analysis using quantitative real-time reverse transcriptase PCR suggested that the NlABCG transcript was expressed at all developmental stages of N. lugens. The lowest expression of NlABCG was in the 1st instar, and levels increased with larval growth. The transcript profiles of NlABCG were analyzed in various tissues from a 5th instar nymph, and the highest expression was observed in the midgut. These results suggest that the sequence, characteristics, and expression of NlABCG are highly conserved, and basic information is provided for its functional analysis.

  14. ANALYSIS OF DRINKING WATER QUALITY IN THE KIZILYURT DISTRICT OF THE REPUBLIC OF DAGESTAN

    Directory of Open Access Journals (Sweden)

    Juliana Kadieva

    2015-01-01

    Full Text Available Aim. The problem of accessibility to the population with quality drinking water is a major and urgent problems in Russia. At the same time, providing the population with clean drinking water is essential for socio-economic development of the Republic of Dagestan. The paper presents the results of studies of the quality of drinking water in settlements of the Kizilyurt district of Dagestan. Methods. During the monitoring works conducted a questionnaire survey on the quality of life of the population, conducted research to assess the extent of soil contamination, as well as analysis of drinking water quality at 16 inhabited locality in 13 rural settlements Kizilyurt district (Sultan-Yangi-Yurt, Chontaul, Komsomol'skoe, Novyi Chirkei, Stal'skoe, Nechaevka, Zubutli-Miatli, Miatli, Aknada, Kul'zeb, Kirovaul, Shushanovka, Nizhnii Chiryurt, Gel'bakh, Novye Gadari, Matseevka. Studies performed with modern physico-chemical methods of quantitative chemical analysis, regulated by normative documentation approved in the established procedure for monitoring and environmental control. Results. In studies of water sources, it was identified that the main elements of pollution in drinking waters of the study area are compounds of arsenic and iron. Main conclusions. The studies show that, in spite of the undertaken measures aimed at providing the population with quality drinking water, the problems of access of the population Kizilyurt district to clean water are acute today and need a speedy solution.

  15. Knowledge-based on-line vibration monitoring diagnose

    International Nuclear Information System (INIS)

    Johansson, L.G.; Karlsson, A.; Noeremark, A.

    1990-01-01

    ABB STAL developed some years ago a knowledge-based on-line vibration analysis system (working-name KOVA). KOVA is intended to work together with some type of vibration monitoring system, at present it is adapted to TVM 300. KOVA has no controlling function. It will only diagnose the actual situation and give the user explanations and proposals for actions to be taken. During the developing work, great experience has been gained of the features this type of system demands. This paper will present the outlines of the application and also discuss how to make diagnoses based both on general rules as well as on historical vibration cases for that particular unit (or identical units9. Another subject that this paper will outline, is the representation and evaluation of knowledge. KOVA serves as a decision-support system for the operator. Since KOVA will often give the operator more than one possible diagnosis as the cause of a fault, it is of great importance to give the operator comprehensive explanations and as many facts as possible. It is also important to rank the suggested diagnoses in some way. In KOVA these demands are effectively supported. The models and tools used to realize this functionality will be described in this paper

  16. Population dynamic of the swallowtail butterfly, Papilio polytes (Lepidoptera: Papilionidae in dry and wet seasons

    Directory of Open Access Journals (Sweden)

    SUWARNO

    2010-01-01

    Full Text Available Suwarno (2010 Population dynamic of the swallowtail butterfly, Papilio polytes (Lepidoptera: Papilionidae in dry and wet seasons. Biodiversitas 11: 19-23. The population dynamic of Papilio polytes L. (Lepidoptera: Papilionidae in dry and wet seasons was investigated in the citrus orchard in Tasek Gelugor, Pulau Pinang, Malaysia. Population of immature stages of P. polytes was observed alternate day from January to March 2006 (dry season, DS, from April to July 2006 (secondary wet season, SWS, and from October to December 2006 (primary wet season, PWS. The population dynamics of the immature stages of P. polytes varied between seasons. The immature stages of P. polytes are more abundance and significantly different in the PWS than those of the DS and the SWS. The larval densities in all seasons decreased with progressive development of the instar stages. Predators and parasitoids are the main factor in regulating the population abundance of immature stages of P. polytes. There were positive correlations between the abundance of immature stages of P. polytes and their natural enemies abundance in each season. Ooencyrtus papilioni Ashmead (Hymenoptera: Encyrtidae is the most egg parasitoid. Oxyopes quadrifasciatus L. Koch. and O. elegans L. Koch. (Araneae: Oxyopidae are the main predators in the young larvae, meanwhile Sycanus dichotomus Stal. (Heteroptera: Reduviidae, Calotes versicolor Fitzinger (Squamata: Agamidae, birds and praying mantis attacked the older larvae.

  17. The extension of Ubungo power plant in Dar es Salaam, Tanzania, to a combined cycle - A prestudy

    Energy Technology Data Exchange (ETDEWEB)

    Grinneland, L; Oehrstroem, K

    1996-05-01

    The report deals with the consequences concerning a future extension of Ubungo Power Plant. Today the power plant consists of four gas turbines, two of model General Electric LM6000 and two of model ABB Stal GT10 of which the latter were the ones focused on. In the report four different applications are presented; Simple two pressure system, Two pressure system with reheat, Two pressure system with heat exchange between feedwater and condensate, and single pressure system with an additional evaporating loop. The calculations are divided into three sections; thermodynamic calculations, calculations of the heat exchanger surface areas, and economic calculations. From the thermodynamic calculations the applications with the highest thermal efficiency was selected. The power output increased with about 55% and the thermal efficiency of the complete combined cycle is 48.2%. This is, of course, a theoretical value calculated without consideration to a number of losses that will decrease both the power output and the thermal efficiency. At part load (50% load assumed, i.e. one gas turbine is operating) the thermal efficiency is 46.7%. The economic calculations indicated that the extension is highly worthwhile in an economic point of view; both cases studied have a payback time of less than six years for full load operation, provided that the charging system which is to be imposed by the World Bank has come into force. 18 refs, 33 figs

  18. GEODATA: Information System Based on Geospatial for Early Warning Tracking and Analysis Agricultural Plant Diseases in Central Java

    Science.gov (United States)

    Prasetyo, S. Y. J.; Agus, Y. H.; Dewi, C.; Simanjuntak, B. H.; Hartomo, K. D.

    2017-03-01

    The Government of Indonesia is currently faced with the problems of food, especially rice. It needs in large numbers that have to import from neighboring countries. Actually, the Indonesian government has the ability to produce rice to meet national needs but is still faced with the problem of pest attack rice annually increasing extent. One of the factors is that geographically Indonesia located on the migration path of world rice insect pests (called BPH or Brown Planthoppers) (Nilaparvata lugens Stal.) It leads endemic status annually. One proposed strategy to be applied is to use an early warning system based on a specific region of the main pest population. The proposed information system called GEODATA. GEODATA is Geospatial Outbreak of Disease Tracking and Analysis. The system works using a library ESSA (Exponential Smoothing - Spatial Autocorrelation) developed in previous studies in Satya Wacana Christian University. GEODATA built to meet the qualifications required surveillance device by BMKG (Indonesian Agency of Meteorology, Climatology and Geophysics’ Central Java Provinces), BPTPH (Indonesian Agency of Plant Protection and Horticulture) Central Java Provinces, BKP-KP District Boyolali, Central Java, (Indonesian Agency of Food Security and Agriculture Field Supervisor, District Boyolali, Central Java Provinces) and farmer groups. GIS GEODATA meets the needs of surveillance devices that include: (1) mapping of the disease, (2) analysis of the dynamics of the disease, and (3) prediction of attacks / disease outbreaks in a particular region. GIS GEODATA is currently under implementation in the laboratory field observations of plant pest in Central Java province, Indonesia.

  19. Sphaerionini (Coleoptera, Cerambycidae, Cerambycinae: novos taxons, sinonímia, chaves e nova combinação

    Directory of Open Access Journals (Sweden)

    Ubirajara R Martins

    1990-01-01

    Full Text Available New taxa described: Neomallocera, gen. n., type-species, Mallocera opulenta Newman, 1841; Protomallocera, gen. n., type-species, Mallocera hilairei Gounelle, 1908; Championa chemsaki, sp. n. (Mexico: Chiapas; Parasphaerion, gen. n., type-species, P. granulosum, sp. n. (Suriname; Mephritus quadrimaculatus, sp. n. (Bolivia: Cochabamba. M. castaneus, sp. n. (Peru: Pasco; M. fraterculus, sp. n. (Peru: Cajamarca; Nesostizocera suturalis. sp. n. (Peru and Ecuador; Morphaneflus, gen. n., type-species, M. prolixus, sp. n. (Argentina: Salta, Jujuy; Amethysphaerion eximium, sp. n. (Ecuador; A. jocosum, sp. n. (Brazil: Espírito Santo; A. submetallicum, sp. n. (Brazil: Minas Gerais; A. guarani, sp. n. (Paraguay; Aposphaerion punctulatum, sp. n. (Brazil: Amazonas; Pilisphaerion, gen. n., type-species, P. exoticum, sp. n. (Brazil: Pará; Adiposphaerion, gen n., type-species. A. rubrum, sp. n. (Brazil: Amazonas; Minipsyrassa guanabarina, sp. n. (Brazil: Rio de Janeiro; Sphaerioeme, gen. n., type-species, S. rubristerna, sp. n. (Suriname, Brazil: Goiás, Mato Grosso, Minas Gerais, São Paulo, Paraná; Apoclausirion. gen. n., type-species, A. nigricorne (Brazil: Mato Grosso. Mallocera pickeli Melzer, 1931 is considered a synonym of M. simplex White, 1853. Psyrassa trinidadensis Gilmour, 1963 is transferred to the genus Amethysphaerion. Keys to the genera related with Mallocera and to the species of Amethysphaerion are added.

  20. Genome sequencing of the sweetpotato whitefly Bemisia tabaci MED/Q.

    Science.gov (United States)

    Xie, Wen; Chen, Chunhai; Yang, Zezhong; Guo, Litao; Yang, Xin; Wang, Dan; Chen, Ming; Huang, Jinqun; Wen, Yanan; Zeng, Yang; Liu, Yating; Xia, Jixing; Tian, Lixia; Cui, Hongying; Wu, Qingjun; Wang, Shaoli; Xu, Baoyun; Li, Xianchun; Tan, Xinqiu; Ghanim, Murad; Qiu, Baoli; Pan, Huipeng; Chu, Dong; Delatte, Helene; Maruthi, M N; Ge, Feng; Zhou, Xueping; Wang, Xiaowei; Wan, Fanghao; Du, Yuzhou; Luo, Chen; Yan, Fengming; Preisser, Evan L; Jiao, Xiaoguo; Coates, Brad S; Zhao, Jinyang; Gao, Qiang; Xia, Jinquan; Yin, Ye; Liu, Yong; Brown, Judith K; Zhou, Xuguo Joe; Zhang, Youjun

    2017-05-01

    The sweetpotato whitefly Bemisia tabaci is a highly destructive agricultural and ornamental crop pest. It damages host plants through both phloem feeding and vectoring plant pathogens. Introductions of B. tabaci are difficult to quarantine and eradicate because of its high reproductive rates, broad host plant range, and insecticide resistance. A total of 791 Gb of raw DNA sequence from whole genome shotgun sequencing, and 13 BAC pooling libraries were generated by Illumina sequencing using different combinations of mate-pair and pair-end libraries. Assembly gave a final genome with a scaffold N50 of 437 kb, and a total length of 658 Mb. Annotation of repetitive elements and coding regions resulted in 265.0 Mb TEs (40.3%) and 20 786 protein-coding genes with putative gene family expansions, respectively. Phylogenetic analysis based on orthologs across 14 arthropod taxa suggested that MED/Q is clustered into a hemipteran clade containing A. pisum and is a sister lineage to a clade containing both R. prolixus and N. lugens. Genome completeness, as estimated using the CEGMA and Benchmarking Universal Single-Copy Orthologs pipelines, reached 96% and 79%. These MED/Q genomic resources lay a foundation for future 'pan-genomic' comparisons of invasive vs. noninvasive, invasive vs. invasive, and native vs. exotic Bemisia, which, in return, will open up new avenues of investigation into whitefly biology, evolution, and management. © The Author 2017. Published by Oxford University Press.

  1. Morphology of the spermathecae of twelve species of Triatominae (Hemiptera, Reduviidae) vectors of Chagas disease.

    Science.gov (United States)

    Nascimento, Juliana Damieli; Ribeiro, Aline Rimoldi; Almeida, Larissa Aguiar; de Oliveira, Jader; Mendonça, Vagner José; Cilense, Mário; da Rosa, João Aristeu

    2017-12-01

    Trypanosoma cruzi, the etiological agent of Chagas disease, is transmitted by triatomines that have been described in a large number of studies. Most of those studies are related to external morphology and taxonomy, but some biochemical, genetic and physiological studies have also been published. There are a few publications in the literature about the internal organs of Triatominae, for instance the spermathecae, which are responsible for storing and maintaining the viability of the spermatozoids until the fertilization of the oocytes. This work aims to study the spermathecae of twelve species of triatomines obtained from the Triatominae Insectarium of the Faculty of Pharmaceutical Sciences, UNESP, Araraquara, using optical microscopy and scanning electron microscopy. The spermathecae of the twelve species studied showed three morphological patterns: a) P. herreri sn, P. lignarius, P. megistus, Triatoma brasiliensis, T. juazeirensis, T. sherlocki and T. tibiamaculata have spermathecae with a thin initial portion and an oval-shaped final portion; b) R. montenegrensis, R. nasutus, R. neglectus, R. pictipes and R. prolixus have tubular and winding spermathecae; c) T. infestans has oval spermathecae. In addition to the three morphological patterns, it was noted that each of the twelve species has particular features that differentiate them. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Prevalência, índices de infecção e hábitos alimentares de triatomíneos capturados em uma área de vigilância epidemiológica

    Directory of Open Access Journals (Sweden)

    Vera Lúcia C. Corrêa Rodrigues

    1992-09-01

    Full Text Available Em continuação a estudo anterior, relativo à prevalência e infecção por Trypanosoma cruzi dos triatomíneos capturados na região administrativa de Campinas, SP, os autores apresentam dados do período de 1982-1986, acrescentando informações sobre respastos sangüíneos realizados por 7.785 exemplares. Para tanto, foram utilizados os anti-soros: ave, marsupial, roedor e humano, através dos quais constataram o ecletismo alimentar de Panstrongylus megistus, espécie predominante na região, cujas formas aladas são encontradas com freqüência, infectadas por T. cruzi, nas casas habitadas. Desses, 14,78% reagiram frente ao anti-soro humano. Com Rhodnius neglectus foi observada situação assemelhada, mas com números menos expressivos. Em relação ao Triatoma sórdida, não foi constatada infecção natural e tampouco sinais de ingestão de sangue humano. Foi constatado acentuado aumento de T. arthurneivai nas casas, fruto da provável modificação ocorrida no ambiente natural. No período, foi encontrado Microtiatoma borbai, detectado pela primeira vez no Estado de São Paulo. Ressaltam também a importância da "investigação de foco " nas áreas em fase de vigilância.Prevalence of triatomines and their infection by Trypanosoma cruzi, were studied during 1974-1981, in the Administrative Region of Campinas, São Paulo, Brazil. This investigation was continued (1982-1986, blood meal tests with bird, marsupial, rodent and human antisera having been added. Panstrongylus megistus, predominant in the region, whose winged instars are often found infected by T. cruzi in inhabited houses, displayed and alimentary eclecticism. From a sample of 7,785, 14.78 percent reacted positively with human antisera. A similar, but less marked behaviour was observed in Rhodnius neglectus. Triatoma sordida, the secondmost important species in the Region, was neither demonstrated to be feeding on humans nor to be infected by T. cruzi. Changes in their

  3. Tripanosomiasis americana: determinación de riesgo epidemiológico de transmisión en el municipio de Amalfi, Antioquia American trypanosamiasis: determination of epidemiologic transmission risk in Amalfi, Antioquia, Colombia

    Directory of Open Access Journals (Sweden)

    John Jairo Arboleda

    2001-02-01

    Full Text Available Se presenta por primera vez en antioquia un estudio sobre la enfermedad de Chagas, en el cual se evaluaron simultáneamente los tres componentes fundamentales de esta parasitosis: vector, parásito y reservorio. Se evaluaron 640 domicilios en 9 veredas del municipio de Amalfi, se capturaron 196 triatominos, pertenecientes a las especies Panstrongylus geniculatus (49%, P. rufotuberculatus (47%, Triatoma dispar (3% y Rhodnius pallescens (0.5%. En total se capturaron 33 animales silvestres, pertenecientes a las especies Didelphis marsupialis (8, Marmosa robinsoni (1, Hoplomys gimnurus (3, Dasypus novemcinctus (2, Proechymis sp (13, Oryzomis sp (3, Philander opossum (3, así como 63 perros (Canis lupus. Los indicadores de riesgo de transmisión de Tripanosoma cruzi por triatominos, fueron: dispersión (100%, infestación domiciliaria (14,5%, densidad (30,5%, hacinamiento (204,2% e infección relativa (12,5%. Se obtuvo una alta prevalencia de anticuerpos en los perros de las veredas Montebello (61.1% y La Gardenia (70.0% y serología positiva en un humano adulto. In this paper we report the first Chagas disease study in Antioquia-Colombia, in which the main components of this disease were simultaneously evaluated: vector, parasite and host. Field studies were carried out evaluating 640 houses in nine localities from the municipality of Amalfi; 196 triatomine bugs were captured: Panstrongylus geniculatus (49%, Panstrongylus rufotuberculatus (47%, Triatoma dispar (3% and Rhodnius pallescens (0.5%. Thirty three wild animals were captured: Didelphis marsupialis (8, Marmosa robinsoni (1, Hoplomys gimnurus (3, Dasypus novemcinctus (2, Proechymis sp (13, Oryzomis sp (3, Philander opossum (3 as well as 63 dogs (Canis lupus. Transmission risk indicators for Trypanosoma cruzi were: Dispersion (100%, Domiciliary infestation (14,5%, Insect density (30,5%, crowding (204,2% and Relative infection (12,5%. Of the nine localities studied, Montebello (61.1% and La

  4. Drivers of house invasion by sylvatic Chagas disease vectors in the Amazon-Cerrado transition: A multi-year, state-wide assessment of municipality-aggregated surveillance data.

    Directory of Open Access Journals (Sweden)

    Raíssa N Brito

    2017-11-01

    Full Text Available Insecticide spraying efficiently controls house infestation by triatomine bugs, the vectors of Trypanosoma cruzi. The strategy, however, is ineffective against sylvatic triatomines, which can transmit Chagas disease by invading (without colonizing man-made structures. Despite growing awareness of the relevance of these transmission dynamics, the drivers of house invasion by sylvatic triatomines remain poorly understood.About 12,000 sylvatic triatomines were caught during routine surveillance in houses of Tocantins state, Brazil, in 2005-2013. Using negative binomial regression, information-theoretic model evaluation/averaging, and external model validation, we investigated the effects of regional (Amazon/Cerrado, landscape (preservation/disturbance, and climate covariates (temperature, rainfall on the municipality-aggregated numbers of house-invading Rhodnius pictipes, R. robustus, R. neglectus, and Panstrongylus geniculatus. House invasion by R. pictipes and R. robustus was overall more frequent in the Amazon biome, tended to increase in municipalities with more well-preserved land, and decreased in rainier municipalities. Across species, invasion decreased with higher landscape-disturbance levels and in hotter-day municipalities. Invasion by R. neglectus and P. geniculatus increased somewhat with more land at intermediate disturbance and peaked in average-rainfall municipalities. Temperature effects were more pronounced on P. geniculatus than on Rhodnius spp.We report widespread, frequent house invasion by sylvatic triatomines in the Amazon-Cerrado transition. Our analyses indicate that readily available environmental metrics may help predict the risk of contact between sylvatic triatomines and humans at coarse geographic scales, and hint at specific hypotheses about climate and deforestation effects on those vectors-with some taxon-specific responses and some seemingly general trends. Thus, our focal species appear to be quite sensitive to

  5. Ganancia de peso del depredador Podisus distinctus (Heteroptera: Pentatomidae en combinaciones de las presas Tenebrio molitor (Coleoptera: Tenebrionidae y Musca domestica (Diptera: Muscidae

    Directory of Open Access Journals (Sweden)

    Fausto da Costa Matos Neto

    2004-03-01

    Full Text Available Entre las ninfas de los asopíneos usados para el control de gusanos desfoliadores en plantaciones de eucalipto, Podisus distinctus (Stal (Heteroptera: Pentatomidae representa un potencial agente de control biológico, sin embargo esta especie ha sido poco estudiada. El presente trabajo evaluó el efecto de las diferentes combinaciones de las presas Musca domestica L. (Diptera: Muscidae y Tenebrio molitor L. (Coleoptera: Tenebrionidae sobre el peso de ninfas de P. distinctus. El experimento se realizó en laboratorio do "Instituto de Biotecnologia Aplicada à Agropecuaria (BIOAGRO", a 25 ± 0.5ºC, 60 ± 10% de humedad relativa y 14 horas de fotoperiodo. Las ninfas de P. distinctus fueron individualizadas en cajas de Petri y alimentadas de acuerdo con los siguientes tratamientos: T1- larvas de M. domestica durante toda la fase ninfal; T2- larvas de M. domestica en el II estadio y de T. molitor en los III, IV y V estadios; T3- larvas de M. domestica en el II y III estadios y de T. molitor en los IV y V estadios; T4- larvas de M. domestica en el II, III y IV estadios y de T. molitor en el V estadio; T5- larvas de T. molitor en todos los estadios. Los mejores resultados de peso y ganancia de peso fueron encontrados cuando P. distinctus fue alimentado alternadamente con larvas de M. domestica y T. molitor. Cuando esse depredador fue solamente alimentado con larvas de M. domestica, presentó pesos menoresLitlle is known about Podisus distinctus (Stal (Heteroptera: Pentatomidae one of the Asopinae species with good possibilities for mass rearing and releasing against defoliator caterpillars in eucalyptus reforested areas in Brazil. We evaluated the impact of prey combinations on weight of nymphs and adults of P. distinctus. The prey were Musca domestica L. (Diptera: Muscidae and Tenebrio molitor L. (Coleoptera: Tenebrionidae. The experiment was developed under 25 ± 0.5ºC, 60 ± 10% R.H. and photophase of 14 hr, with nymphs of P. distinctus

  6. Effectiveness of emission reducing measures for cattle farms; Effectiviteit van emissiereducerende maatregelen rondom veehouderijbedrijven

    Energy Technology Data Exchange (ETDEWEB)

    Kraai, A.; Bleeker, A. [ECN, Biomassa, Kolen en Milieuonderzoek, Petten (Netherlands)

    2007-11-15

    The results of a survey on the cost effectiveness of measures with the goal to reduce emissions of fine dust from livestock production are presented. All these measures have their advantages and disadvantages. This report mainly focuses on the reduction of particulate matter. Other environmental problems in agriculture, e.g. ammonia and odour, can also be tackled with these measures. Different measures are compared for cost effectiveness in Euro per kg PM10 reduction and also the reduction percentage. Oil sprinkling and electrostatic filter systems appear as cost effective and the air quality in the air as well as in the stable is improved. These techniques can be combined with end-of-pipe techniques, e.g. air scrubbers, or even better, combined scrubbers to reduce other emissions as ammonia and odour. Many techniques are still in a research phase; therefore estimations are made most of the times. More measuring has to be carried to improve the accuracy of the reduction percentages. Besides, practical feasibility and animal welfare have to be taken into account with every measure taken. [Dutch] In deze rapportage is de kosteneffectiviteit van maatregelen in kaart gebracht, die als doel hebben de fijnstofemissies vanuit de landbouw te reduceren. In deze rapportage is vooral gezocht naar maatregelen om fijn stof te reduceren. De andere milieuproblemen in de landbouw als ammoniak en geur zouden hiermee eveneens gereduceerd kunnen worden. Uit de analyse is gebleken dat alle voermaatregelen kostbaar zijn terwijl de reductie niet erg groot is, deze opties zijn daardoor minder kosteneffectief. Olie vernevelen en het toepassen van een elektrostatisch filter lijken effectieve en niet te kostbare maatregelen, waarbij ook de luchtkwaliteit in de stal wordt verbeterd. Deze technieken zouden gecombineerd kunnen worden met de luchtwassers of gecombineerde wassers om meerdere luchtverontreinigingscomponenten te reduceren. Vegetatie aanplanten rondom boerderijen is een optie die

  7. Monitoramento populacional das cigarrinhas vetoras de Xylella fastidiosa, através de armadilhas adesivas amarelas em pomares comerciais de citros Population monitoring of leafhopper vectors of Xylella fastidiosa, through yellow sticky traps in commercial citrus orchards

    Directory of Open Access Journals (Sweden)

    Rúbia de Oliveira Molina

    2010-12-01

    Full Text Available A Clorose variegada dos citros (CVC é uma doença causada pela bactéria de xilema Xylella fastidiosa Wells. A disseminação ocorre por meio de insetos vetores pertencente à ordem Hemiptera, família Cicadellidae (subfamília Cicadellinae, os quais transmitem a bactéria depois de se alimentarem em plantas contaminadas. Neste trabalho, objetivou-se identificar e monitorar as espécies de cigarrinhas vetoras em um pomar comercial no município de Paranavaí, Paraná. O experimento foi realizado em um talhão comercial de laranja doce (Citrus sinensis (L. Osbeck, variedade Pera, com 1.000 plantas de dez anos de idade. A amostragem foi realizada por meio de armadilhas adesivas amarelas, distribuídas na área periférica e central do pomar, com duas repetições por rua amostrada. As etiquetas foram distribuídas entre a 5ª e 30ª plantas em 10 ruas, totalizando 20 armadilhas que foram renovadas no pomar, a cada trinta dias, durante o período de avaliação que foi entre junho de 2005 e setembro de 2006. As principais espécies de Cicadellinae capturadas foram Acrogonia citrina Marucci & Cavichioli, Dilobopterus costalimai Young e Macugonalia cavifrons Stal. Essas espécies apresentaram ocorrência constante e frequência de 3,97%, 4,2%, 13,0% respectivamente, em relação ao total de cigarrinhas coletadas.Citrus variegated chlorosis (CVC is the disease caused by the bacteria Xylella fastidiosa Wells. Dissemination occurs through insect vectors belonging to the order Hemiptera, family Cicadellidae (subfamily Cicadellinae, which transmit the bacteria after feeding on infected plants. The objective of this study was to identify the species of insect vectors in an orchard in the municipality of Paranavaí, in the State of Paraná. The experiment was conducted in a commercial stand of sweet orange (Citrus sinensis (L. Osbeck, Pêra variety with 1,000 10-year-old plants. Monitoring was performed using yellow sticky traps, distributed in the central

  8. Seleksi Resistansi Wereng Batang Padi Coklat terhadap Insektisida Fipronil

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    Melhanah Melhanah

    2002-12-01

    Full Text Available The rice brown planthoper, Nilaparvata lugens Stal (Homoptera: Delphacidae, is one of  key pests on rice. The use of insecticides unwisely has caused N. lugens to develop resistance. The objective of this research was to determine the potency of N. lugens to develop resistance through laboratory, selections to fipronil, a relatively new insecticide.  A population of N. lugens was collected from rice field in Muntilan, Central Java during the outbreak in 2001. Selections were carried out every generation for four generations against third instars. Selection was started by dipping Cisadane rice seedlings in a solution of fipronil (50 ppm. The concentration was increased every generation, and the concentration used for the last selection (the fourth generation was 250 ppm. To determine the rate of resistance development, biassays were carried out to estimate LC50 of fipronil against selected and non-selected populations of N. lugens, and their LC50 values were compared to that of the laboratory population. The laboratory population has been in the laboratory for 15 years without any insecticides exposure. The founding population was as susceptible as the laboratory population to fipronil because their LC50 values were similar. Even though the concentration for selections was increased from generation to generation, the survival rate of N. lugens increased steadily. After four generations of selection, the resistance of selected population was 27.3 times than the non-selected population. These findings indicate that N. lugens population has the potency to develop resistance to fipronil in a continuous selection pressure is applied.

  9. Una metodología muestral sugerida para la estimación de la población de la chinche de los pastos en la sabana de Bogotá

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    Galindo Julio Ricardo

    2001-12-01

    Full Text Available La chinche de los pastos (Collaria scenica Stal es una plaga
    del pasto kikuyo (Pennisetum clandestinum que causa alrededor de un 25% de pérdidas en el ingreso de los ganaderos en la Sabana de Bogotá. La evaluación de las poblaciones del insecto y su dinámica es esencial para el desarrollo de investigación en métodos de manejo del problema. En este trabajo se seleccionaron dos lotes de kikuyo de aproximadamente 1 ha, para determinar
    una metodología eficiente, económica y precisa de estimación
    de la población de estados inmaduros y adultos del insecto,
    utilizando la técnica deljameo. Se tomaron 39 muestras aproximadamente por lote y se hicieron visitas cada dos semanas, para un total de cinco. Con esta información se determinó el patrón de disposición espacial de la plaga y se definieron tamaños de muestra para niveles de precisión determinados. Además se propuso un tamaño del lote con fines de realización de pruebas experimentales, de 1/3 de ha. Finalmente se determinó la conveniencia de hacer paso y repaso sobre el recorrido de la unidad de muestreo, con el fin de lograr una mejor aproximación a la población total del insecto en el lote.

  10. Stainless-Steel-Gadolinium Alloys; Alliages Acier Inoxydable-Gadolinium; Splavy iz nerzhaveyushchej stali i gadoliniya; Aleaciones de Acero Inoxidable-Gadolinio

    Energy Technology Data Exchange (ETDEWEB)

    Copeland, M.; Kato, H. [Albany Metallurgy Research Center, Bureau Of Mines, United States Department of the Interior, Albany, OR (United States)

    1964-06-15

    -niquel, se observan dos fases menores, Fe{sub 9}Gd y Ni{sub 7}Gd.'que funden a 1080 Degree-Sign C, lo que limita las temperaturas de tratamiento termico y de trabajo. Se lograron obtener aleaciones que contenian 5% en peso de gadolinio y se determinaron sus propiedades mecanicas y de corrosion. Aleando el acero con hasta un 3% en peso de gadolinio, no se observaron alteraciones de las propiedades mecanicas ni de la resistencia a la corrosion por agua caliente. Las restricciones de la temperatura de obtencion que el punto de fusion'de las fases menores impone a los aceros al cromo-niquel obligaron a estudiar los efectos del gadolinio sobre los aceros al cromo. Al investigar el isopleta correspondiente al 10% en peso de gadolinio en el sistema cromo-hierro-gadolinio, solo se observo una fase menor cuyo punto de fusion es 1320 Degree-Sign C. Por consiguiente, los autores estiman posible equilibrar y elaborar estos aceros al gadolinio a las temperaturas normalmente empleadas en esos casos. (author) [Russian] Vsledstvie horoshej stojkosti k korrozii nerzhavejushhej stali i interesa k gadoliniju, kak k veshhestvu, pogloshhaeshhemu nejtrony, izuchalis' splavy jetih dvuh materialov. Gadolinij byl splavlen s nerzhavejushhej stal'ju tipa AISI 304 i hromirovannoj nerzhavejushhej stal'ju i zatem byli izucheny sootnoshenija fa z, svojstva i vozmozhnost' izgotovlenija. Tochki plavlenija vtorostepennyh faz v splavah, v kotoryh imelos' nizkoe procentnoe soderzhanie gadolinija, kak bylo otmecheno, okazyvajut bol'shoe vlijanie na struktury vsledstvie ravnomernoj obrabotki i izgotovlenija stali. Pri izuchenii splava gadolinija s hromo-nikelevoj stal'ju nabljudalis' dve vtorostepennye fazy Fe{sub 9}Gd i Ni{sub 7}Gd plavlenija pri temperature 1,080 Degree-Sign S, chto ogranichilo temperaturu gorjachej obrabotki i izgotovlenija. Uspeshno izgotovljalis' splavy s soderzhaniem gadolinija do 5 ves.% i byli opredeleny mehanicheskie i korrozijnye svojstva. Ne nabljudalos' izmenenij v mehanicheskih

  11. Development of 25 near-isogenic lines (NILs) with ten BPH resistance genes in rice (Oryza sativa L.): production, resistance spectrum, and molecular analysis.

    Science.gov (United States)

    Jena, Kshirod K; Hechanova, Sherry Lou; Verdeprado, Holden; Prahalada, G D; Kim, Sung-Ryul

    2017-11-01

    A first set of 25 NILs carrying ten BPH resistance genes and their pyramids was developed in the background of indica variety IR24 for insect resistance breeding in rice. Brown planthopper (Nilaparvata lugens Stal.) is one of the most destructive insect pests in rice. Development of near-isogenic lines (NILs) is an important strategy for genetic analysis of brown planthopper (BPH) resistance (R) genes and their deployment against diverse BPH populations. A set of 25 NILs with 9 single R genes and 16 multiple R gene combinations consisting of 11 two-gene pyramids and 5 three-gene pyramids in the genetic background of the susceptible indica rice cultivar IR24 was developed through marker-assisted selection. The linked DNA markers for each of the R genes were used for foreground selection and confirming the introgressed regions of the BPH R genes. Modified seed box screening and feeding rate of BPH were used to evaluate the spectrum of resistance. BPH reaction of each of the NILs carrying different single genes was variable at the antibiosis level with the four BPH populations of the Philippines. The NILs with two- to three-pyramided genes showed a stronger level of antibiosis (49.3-99.0%) against BPH populations compared with NILs with a single R gene NILs (42.0-83.5%) and IR24 (10.0%). Background genotyping by high-density SNPs markers revealed that most of the chromosome regions of the NILs (BC 3 F 5 ) had IR24 genome recovery of 82.0-94.2%. Six major agronomic data of the NILs showed a phenotypically comparable agronomic performance with IR24. These newly developed NILs will be useful as new genetic resources for BPH resistance breeding and are valuable sources of genes in monitoring against the emerging BPH biotypes in different rice-growing countries.

  12. High-resolution genetic mapping at the Bph15 locus for brown planthopper resistance in rice (Oryza sativa L.).

    Science.gov (United States)

    Yang, Haiyuan; You, Aiqing; Yang, Zhifan; Zhang, Futie; He, Ruifeng; Zhu, Lili; He, Guangcun

    2004-12-01

    Resistance to the brown planthopper (BPH), Nilaparvata lugens Stal, a devastating sucking insect pest of rice, is an important breeding objective in rice improvement programs. Bph15, one of the 17 major BPH resistance genes so far identified in both cultivated and wild rice, has been identified in an introgression line, B5, and mapped on chromosome 4 flanked by restriction fragment length polymorphism markers C820 and S11182. In order to pave the way for positional cloning of this gene, we have developed a high-resolution genetic map of Bph15 by positioning 21 DNA markers in the target chromosomal region. Mapping was based on a PCR-based screening of 9,472 F(2) individuals derived from a cross between RI93, a selected recombinant inbred line of B5 bearing the resistance gene Bph15, and a susceptible variety, Taichung Native 1, in order to identify recombinant plants within the Bph15 region. Recombinant F(2) individuals with the Bph15 genotype were determined by phenotype evaluation. Analysis of recombination events in the Bph15 region delimited the gene locus to an interval between markers RG1 and RG2 that co-segregated with the M1 marker. A genomic library of B5 was screened using these markers, and bacterial artificial chromosome clones spanning the Bph15 chromosome region were obtained. An assay of the recombinants using the sub-clones of these clones in combination with sequence analysis delimited the Bph15 gene to a genomic segment of approximately 47 kb. This result should serve as the basis for eventual isolation of the Bph15 resistance gene.

  13. Movimentos de migração e dispersão de adultos da cigarrinha-das-pastagens

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    SUJII EDISON RYOITI

    2000-01-01

    Full Text Available O efeito do movimento de adultos da cigarrinha-das-pastagens (Deois flavopicta Stal em sua dinâmica populacional foi avaliado em pastagens de Brachiaria ruziziensis na região do Distrito Federal, Brasil. Foram utilizados painéis de plástico com cola adesiva para monitorar as taxas de movimentação. Os dados sugerem a ausência de um padrão predominante de movimentação em relação à posição geográfica das armadilhas. A ocorrência de vegetação baixa, semelhante às pastagens em volta da área estudada, aparentemente favoreceu a dispersão, ao passo que a ocorrência de cerrados ou matas na vizinhança inibiu o movimento nesta direção e aumentou a taxa de retorno da cigarrinha às pastagens. O inseto se deslocou principalmente mediante saltos ou vôos curtos e baixos (abaixo de 1 m. Uma proporção aproximada de 4:1 (macho:fêmea foi capturada nas armadilhas, indicando que os machos movimentam-se mais que as fêmeas. A velocidade média de movimentação, de populações marcadas com pó fluorescente atóxico e recapturadas após períodos variáveis de liberação, foi inferior a 5 m por dia. O movimento de dispersão de adultos não contribui significativamente para a perda ou recrutamento de adultos em populações de D. flavopicta, a não ser em casos de explosões populacionais ou extinção local.

  14. Effects of dating errors on nonparametric trend analyses of speleothem time series

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    M. Mudelsee

    2012-10-01

    Full Text Available A fundamental problem in paleoclimatology is to take fully into account the various error sources when examining proxy records with quantitative methods of statistical time series analysis. Records from dated climate archives such as speleothems add extra uncertainty from the age determination to the other sources that consist in measurement and proxy errors. This paper examines three stalagmite time series of oxygen isotopic composition (δ18O from two caves in western Germany, the series AH-1 from the Atta Cave and the series Bu1 and Bu4 from the Bunker Cave. These records carry regional information about past changes in winter precipitation and temperature. U/Th and radiocarbon dating reveals that they cover the later part of the Holocene, the past 8.6 thousand years (ka. We analyse centennial- to millennial-scale climate trends by means of nonparametric Gasser–Müller kernel regression. Error bands around fitted trend curves are determined by combining (1 block bootstrap resampling to preserve noise properties (shape, autocorrelation of the δ18O residuals and (2 timescale simulations (models StalAge and iscam. The timescale error influences on centennial- to millennial-scale trend estimation are not excessively large. We find a "mid-Holocene climate double-swing", from warm to cold to warm winter conditions (6.5 ka to 6.0 ka to 5.1 ka, with warm–cold amplitudes of around 0.5‰ δ18O; this finding is documented by all three records with high confidence. We also quantify the Medieval Warm Period (MWP, the Little Ice Age (LIA and the current warmth. Our analyses cannot unequivocally support the conclusion that current regional winter climate is warmer than that during the MWP.

  15. Occurrence of synanthropic triatomines (Hemiptera: Reduviidae in the Federal District of Brazil

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    Maicon Hitoshi Maeda

    2012-02-01

    Full Text Available INTRODUCTION: Entomological surveillance of Chagas disease in the Federal District of Brazil (DF, has recorded the following triatomine species: Panstrongylus megistus, P. geniculatus, P. diasi, Rhodnius neglectus, Triatoma pseudomaculata, and T. sordida. We aimed to analyze the spatial and temporal occurrence of triatomine species collected in DF, and their indices of natural infection with trypanosomes. METHODS: The Health State Secretariat of DF recorded triatomines between 2002 and 2010 in 20 administrative regions. This retrospective analysis considered the number of adults and nymphs of each species collected and infected in both intradomicile and peridomicile. RESULTS: A total of 754 triatomines were collected in 252 reported domiciles. Panstrongylus megistus was the most frequent species (65%, followed by T. pseudomaculata (14%. Of the 309 examined insects, only 3 (1% specimens of P. megistus were infected with flagellates morphologically similar to Trypanosoma cruzi. The spatial occurrence indicated a higher diversity of triatomines and frequency of T. sordida in rural areas. Moreover, there was a predominance of P. megistus in urban areas. The number of records of P. megistus in the rainy season was two times higher than that during the dry season. The largest number of triatomines was collected in November. CONCLUSIONS: The presence of P. megistus specimens infected with trypanosomes in domiciles, shows the potential risk of human infection in DF. Thus, it is essential to continue entomological surveillance, intensifying it in the rainy season and in regions of greater occurrence.

  16. Risk factors associated with Trypanosoma cruzi exposure in domestic dogs from a rural community in Panama.

    Science.gov (United States)

    Saldaña, Azael; Calzada, José E; Pineda, Vanessa; Perea, Milixa; Rigg, Chystrie; González, Kadir; Santamaria, Ana Maria; Gottdenker, Nicole L; Chaves, Luis F

    2015-11-01

    Chagas disease, caused by Trypanosoma cruzi infection, is a zoonosis of humans, wild and domestic mammals, including dogs. In Panama, the main T. cruzi vector is Rhodnius pallescens, a triatomine bug whose main natural habitat is the royal palm, Attalea butyracea. In this paper, we present results from three T. cruzi serological tests (immunochromatographic dipstick, indirect immunofluorescence and ELISA) performed in 51 dogs from 24 houses in Trinidad de Las Minas, western Panama. We found that nine dogs were seropositive (17.6% prevalence). Dogs were 1.6 times more likely to become T. cruzi seropositive with each year of age and 11.6 times if royal palms where present in the peridomiciliary area of the dog's household or its two nearest neighbours. Mouse-baited-adhesive traps were employed to evaluate 12 peridomestic royal palms. All palms were found infested with R. pallescens with an average of 25.50 triatomines captured per palm. Of 35 adult bugs analysed, 88.6% showed protozoa flagellates in their intestinal contents. In addition, dogs were five times more likely to be infected by the presence of an additional domestic animal species in the dog's peridomiciliary environment. Our results suggest that interventions focused on royal palms might reduce the exposure to T. cruzi infection.

  17. Chromosomal divergence and evolutionary inferences in Rhodniini based on the chromosomal location of ribosomal genes

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    Sebastian Pita

    2013-05-01

    Full Text Available In this study, we used fluorescence in situ hybridisation to determine the chromosomal location of 45S rDNA clusters in 10 species of the tribe Rhodniini (Hemiptera: Reduviidae: Triatominae. The results showed striking inter and intraspecific variability, with the location of the rDNA clusters restricted to sex chromosomes with two patterns: either on one (X chromosome or both sex chromosomes (X and Y chromosomes. This variation occurs within a genus that has an unchanging diploid chromosome number (2n = 22, including 20 autosomes and 2 sex chromosomes and a similar chromosome size and genomic DNA content, reflecting a genome dynamic not revealed by these chromosome traits. The rDNA variation in closely related species and the intraspecific polymorphism in Rhodnius ecuadoriensis suggested that the chromosomal position of rDNA clusters might be a useful marker to identify recently diverged species or populations. We discuss the ancestral position of ribosomal genes in the tribe Rhodniini and the possible mechanisms involved in the variation of the rDNA clusters, including the loss of rDNA loci on the Y chromosome, transposition and ectopic pairing. The last two processes involve chromosomal exchanges between both sex chromosomes, in contrast to the widely accepted idea that the achiasmatic sex chromosomes of Heteroptera do not interchange sequences.

  18. Species of the subfamily Triatominae Jeannel, 1919 (Hemiptera: Reduviidae present in the Collection of Chagas Disease Vectors (FIOCRUZ-COLVEC, State of Minas Gerais

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    Rita de Cássia Moreira de Souza

    2014-12-01

    Full Text Available Introduction Biological collections are depositories of information on different species and contribute to the knowledge, protection, conservation and maintenance of biodiversity. Methods A list of triatomine species currently included in the Collection of Chagas Disease Vectors (FIOCRUZ-COLVEC was prepared from the database made available by the Reference Center on Environmental Information. Results COLVEC curatorship houses 4,778 specimens of triatomines, of which 811 come from other American countries (Argentina, Bolivia, Colombia, Costa Rica, the United States of America, Guatemala, Mexico, Peru, Uruguay and Venezuela and 3,967 are autochthonous from Brazil. Altogether, 56 species of Chagas disease vectors are represented in the COLVEC: two species of the Tribe Cavernicolini Usinger, 1944; fifteen species of the tribe Rhodniini Pinto, 1926, of which 12 are of the genus Rhodnius and 3 are of the genus Psamolestes; and 39 species of the tribe Triatomini Jeannel, 1919, represented by the genus Dipetalogaster, two species of the genus Eratyrus, two of the genus Meccus, seven of the genus Panstrongylus and 27 of the genus Triatoma. Conclusions This list provides important data on the diversity of triatomines currently included in COLVEC, including the expanded area of Panstrongylus lutzi occurrence in the municipalities Pirapora and Januária, State of Minas Gerais. The maintenance and expansion of the collection ensures the preservation of biodiversity and further studies.

  19. Infestation of arboreal nests of coatis by triatomine species, vectors of Trypanosoma cruzi, in a large Neotropical wetland.

    Science.gov (United States)

    de Lima, Juliane Saab; Rocha, Fabiana Lopes; Alves, Fernanda Moreira; Lorosa, Elias Seixas; Jansen, Ana Maria; de Miranda Mourão, Guilherme

    2015-12-01

    The coati (Nasua nasua, Carnivora) is a medium-sized mammal common in the Pantanal of Brazil. Unlike most mammals, coatis construct arboreal nests used for resting and reproduction. In this region, the coati is an important host of Trypanosoma cruzi, the causative agent of Chagas disease. There are two possible routes through coatis can be infected by T. cruzi: the oral route or the vectorial route. However, the relative importance of each of these routes in the infection of coatis and its role in the sylvatic cycle of the parasite are unknown. Our objectives were to investigate: (i) whether coati nests were infested by triatomine bugs, (ii) what species were frequent in the nests, (iii) whether the triatomines in nests were infected by T. cruzi, and (iv) what were the food resources of these triatomines. Eight of the 24 nests sampled were infested with triatomines, a total of 37 specimens of at least two species (Rhodnius stali and Triatoma sordida). In one nest, R. stali and T. sordida co-occurred and both fed on multiple resources, including coatis. This is the first report of triatomines occurring in arboreal nests of coatis. The co-occurrence of two different genera of triatomine vectors and coatis within the limited space of the coati nests provide multiple opportunities for the exchange of the protozoan parasite through both the vectorial and oral transmission routes. © 2015 The Society for Vector Ecology.

  20. Geographic Distribution of Chagas Disease Vectors in Brazil Based on Ecological Niche Modeling

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    Rodrigo Gurgel-Gonçalves

    2012-01-01

    Full Text Available Although Brazil was declared free from Chagas disease transmission by the domestic vector Triatoma infestans, human acute cases are still being registered based on transmission by native triatomine species. For a better understanding of transmission risk, the geographic distribution of Brazilian triatomines was analyzed. Sixteen out of 62 Brazilian species that both occur in >20 municipalities and present synanthropic tendencies were modeled based on their ecological niches. Panstrongylus geniculatus and P. megistus showed broad ecological ranges, but most of the species sort out by the biome in which they are distributed: Rhodnius pictipes and R. robustus in the Amazon; R. neglectus, Triatoma sordida, and T. costalimai in the Cerrado; R. nasutus, P. lutzi, T. brasiliensis, T. pseudomaculata, T. melanocephala, and T. petrocchiae in the Caatinga; T. rubrovaria in the southern pampas; T. tibiamaculata and T. vitticeps in the Atlantic Forest. Although most occurrences were recorded in open areas (Cerrado and Caatinga, our results show that all environmental conditions in the country are favorable to one or more of the species analyzed, such that almost nowhere is Chagas transmission risk negligible.

  1. Prevalence, Genetic Characterization, and 18S Small Subunit Ribosomal RNA Diversity of Trypanosoma rangeli in Triatomine and Mammal Hosts in Endemic Areas for Chagas Disease in Ecuador.

    Science.gov (United States)

    Ocaña-Mayorga, Sofia; Aguirre-Villacis, Fernanda; Pinto, C Miguel; Vallejo, Gustavo A; Grijalva, Mario J

    2015-12-01

    Trypanosoma rangeli is a nonpathogenic parasite for humans; however, its medical importance relies in its similarity and overlapping distribution with Trypanosoma cruzi, causal agent of Chagas disease in the Americas. The genetic diversity of T. rangeli and its association with host species (triatomines and mammals) has been identified along Central and the South America; however, it has not included data of isolates from Ecuador. This study reports infection with T. rangeli in 18 genera of mammal hosts and five species of triatomines in three environments (domestic, peridomestic, and sylvatic). Higher infection rates were found in the sylvatic environment, in close association with Rhodnius ecuadoriensis. The results of this study extend the range of hosts infected with this parasite and the geographic range of the T. rangeli genotype KP1(-)/lineage C in South America. It was not possible to detect variation on T. rangeli from the central coastal region and southern Ecuador with the analysis of the small subunit ribosomal RNA (SSU-rRNA) gene, even though these areas are ecologically different and a phenotypic subdivision of R. ecuadoriensis has been found. R. ecuadoriensis is considered one of the most important vectors for Chagas disease transmission in Ecuador due to its wide distribution and adaptability to diverse environments. An extensive knowledge of the trypanosomes circulating in this species of triatomine, and associated mammal hosts, is important for delineating transmission dynamics and preventive measures in the endemic areas of Ecuador and Northern Peru.

  2. [Anatomy and histology of salivary glands of Triatominae].

    Science.gov (United States)

    Lacombe, D

    1999-01-01

    Histological studies upon the salivary glands of ten species of triatomine bugs were performed looking for their number and structural organization in different genera. It was possible to evaluate the celular epithelium type of each gland, as well as the merocrine and apocrine secretions of the glands. Secretion run until the hilo and after to salivary pump and hypofaringe. The glandular components, D1, D2 and D3 are always present in the Triatoma, Panstrongylus and Diptelogaster but in Rhodnius there are only the first two pairs of glands. The salivary channels and the hilo are analyzed by histology. The whole pair D3 has a clear valve that regularizes the exit of the secretions to the hilo. According to the genus the valves appear in different locations. They have low and dense epithelium, and their nucleus are rich in chromatin. The secondary channels leaving these valves, are very different, with clear chitinous ringer, low level of chromatin in the nucleus and homogeneous cytoplasm.

  3. Prevalence, Genetic Characterization, and 18S Small Subunit Ribosomal RNA Diversity of Trypanosoma rangeli in Triatomine and Mammal Hosts in Endemic Areas for Chagas Disease in Ecuador

    Science.gov (United States)

    Ocaña-Mayorga, Sofia; Aguirre-Villacis, Fernanda; Pinto, C. Miguel; Vallejo, Gustavo A.

    2015-01-01

    Abstract Trypanosoma rangeli is a nonpathogenic parasite for humans; however, its medical importance relies in its similarity and overlapping distribution with Trypanosoma cruzi, causal agent of Chagas disease in the Americas. The genetic diversity of T. rangeli and its association with host species (triatomines and mammals) has been identified along Central and the South America; however, it has not included data of isolates from Ecuador. This study reports infection with T. rangeli in 18 genera of mammal hosts and five species of triatomines in three environments (domestic, peridomestic, and sylvatic). Higher infection rates were found in the sylvatic environment, in close association with Rhodnius ecuadoriensis. The results of this study extend the range of hosts infected with this parasite and the geographic range of the T. rangeli genotype KP1(−)/lineage C in South America. It was not possible to detect variation on T. rangeli from the central coastal region and southern Ecuador with the analysis of the small subunit ribosomal RNA (SSU-rRNA) gene, even though these areas are ecologically different and a phenotypic subdivision of R. ecuadoriensis has been found. R. ecuadoriensis is considered one of the most important vectors for Chagas disease transmission in Ecuador due to its wide distribution and adaptability to diverse environments. An extensive knowledge of the trypanosomes circulating in this species of triatomine, and associated mammal hosts, is important for delineating transmission dynamics and preventive measures in the endemic areas of Ecuador and Northern Peru. PMID:26645579

  4. Trypanosoma cruzi: Correlations of Biological Aspects of the Life Cycle in Mice and Triatomines

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    Lima Valdirene S

    1999-01-01

    Full Text Available The infection pattern in Swiss mice and Triatomine bugs (Rhodnius neglectus of eleven clones and the original stock of a Trypanosoma cruzi isolate, derived from a naturally infected Didelphis marsupialis, were biochemically and biologically characterized. The clones and the original isolate were in the same zymodeme (Z1 except that two clones were found to be in zymodeme 2 when tested with G6PDH. Although infective, neither the original isolate nor the clones were highly virulent for the mice and lesions were only observed in mice infected with the original stock and one of the clones (F8. All clones and the original isolate infected bugs well while only the original isolate and clones E2 and F3 yielded high metacyclogenesis rates. An observed correlation between absence of lesions in the mammal host and high metacyclogenesis rates in the invertebrate host suggest a evolutionary trade off i.e. a fitness increase in one trait which is accompanied by a fitness reduction in a different one. Our results suggest that in a species as heterogeneous as T. cruzi, a cooperation effect among the subpopulations should be considered.

  5. Investigación de vectores y reservorios en brote de Chagas agudo por posible transmisión oral en Aguachica, Cesar, Colombia

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    Hugo Soto

    2014-04-01

    Full Text Available Colombia tiene un registro de 11 casos de Chagas agudo y 80 casos por contaminación oral con Trypanosoma cruzi. Este trabajo analiza los hallazgos entomológicos y parasitológicos del brote de Aguachica, Cesar, en 2010. Un grupo interdisciplinario de profesionales de la salud y de universidades regionales realizó las pruebas de laboratorio a los pacientes y el estudio del foco de transmisión. Se detectaron 11 casos agudos de enfermedad de Chagas en una sola familia con vivienda sin triatominos domiciliados y, Rhodnius pallescens, Pantrongylus geniculatus, Eratyrus cuspidatus y dos Didelphis marsupialis infectados con T. cruzi en palmas de Attalea butyracea y Elaeis oleifera del área urbana de Aguachica. Se analiza la participación del R. pallescens y el rol de las palmas en el ciclo silvestre de T. cruzi y para la transmisión oral de la enfermedad de Chagas. Incursiones esporádicas de R. pallescens, P. geniculatus y E. cuspidatus silvestres desde palmas cercanas al domicilio humano pueden provocar brotes cada vez más frecuentes de Chagas oral.

  6. Epidemiology of Chagas disease in Ecuador. A brief review

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    Aguilar V H Marcelo

    1999-01-01

    Full Text Available Chagas disease is a complex public health problem that has been underestimated in Ecuador. Here we review the relevant published information, and present unpublished and new data that help to understand the current Chagas disease epidemiological situation and its evolution in the country. Three main characteristics have been identified: (i persistence of Trypanosoma cruzi transmission in already known foci; (ii a marked endemicity in some urban areas of Guayaquil; and (iii the transformation of new Amazon foci into truly endemic areas. The situation in other suspect areas remains uncertain. Five Triatominae species have been implicated in the transmission of T. cruzi to people in Ecuador (Triatoma dimidiata, Rhodnius ecuadoriensis, R. pictipes, R. robustus and Panstrongylus geniculatus, but some others may also play a role in some areas (P. rufotuberculatus, P. howardi, T. carrioni and P. chinai. Other Triatominae reported seem to have little or no epidemiological relevance (T. venosa, T. dispar, Eratyrus mucronatus, E. cuspidatus, P. lignarius and Cavernicola pilosa. High frequency of acute cases and severe chronic disease has been observed. Although cardiomyopathy is more frequent, serious digestive disease is also present. It is estimated that around 120,000-200,000 people may be infected. 2.2 to 3.8 million people are estimated to live under transmission risk conditions.

  7. Biogeography of Triatominae (Hemiptera: Reduviidae in Ecuador: implications for the design of control strategies

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    Abad-Franch Fernando

    2001-01-01

    Full Text Available Chagas disease control strategies strongly depend on the triatomine vector species involved in Trypanosoma cruzi transmission within each area. Here we report the results of the identification of specimens belonging to various species of Triatominae captured in Ecuador (15 species from 17 provinces and deposited in the entomological collections of the Catholic University of Ecuador (Quito, Instituto Oswaldo Cruz (Brazil, the Natural History Museum London (UK, the London School of Hygiene and Tropical Medicine (UK, the National Institute of Hygiene (Quito, and the Vozandes Hospital (Quito. A critical review of published information and new field records are presented. We analysed these data in relation to the life zones where triatomines occur (11 life zones, excluding those over 2,200 m altitude, and provide biogeographical maps for each species. These records are discussed in terms of epidemiological significance and design of control strategies. Findings relevant to the control of the main vector species are emphasised. Different lines of evidence suggest that Triatoma dimidiata is not native to Ecuador-Peru, and that synanthropic populations of Rhodnius ecuadoriensis in southern Ecuador-northern Peru might be isolated from their sylvatic conspecifics. Local eradication of T. dimidiata and these R. ecuadoriensis populations might therefore be attainable. However, the presence of a wide variety of native species indicates the necessity for a strong longitudinal surveillance system.

  8. Book review of Insect Symbiosis. Volume 2. Bourtzis, K.A. and Miller, T.A. editros. 2006 CRC Press, Taylor and Francis Group, Boca Raton, FL, 276 pp. ISBN 0-8493-1286-8

    International Nuclear Information System (INIS)

    Hoy, M.A.

    2007-01-01

    There are several definitions of symbiosis, but in this book it involves an association where one organism (the symbiont) lives within or on the body of another organism (the host), regardless of the actual effect on the host. Some symbioses are mutualistic, some parasitic, and some involve commensalism, in which one partner derives some benefit without either harming or benefiting the other. This is the second volume in this exciting and rapidly advancing topic by these editors. The first volume was published in 2003 and during the intervening three years additional data have been produced that make this book a useful addition to your library. The first book provided chapters that provided an overview of insect symbiosis, discussions of the primary aphid symbiont Buchnera and other aphid symbionts, symbiosis in tsetse, symbionts in the weevil Sitophilus , the possible use of paratransgenic symbionts of Rhodnius prolixis to prevent disease transmission, bark beetle and fungal symbiosis, symbionts of tephritid fruit flies, symbionts affecting termite behavior, an overview of microsporidia as symbionts (parasites?) of insects, an overview of a newly discovered bacterium that causes sex-ratio distortion in insects and mites (from the Bacteroides group), symbionts that selectively kill male insects, and several chapters on the ubiquitous endosymbiont Wolbachia

  9. DataTri, a database of American triatomine species occurrence

    Science.gov (United States)

    Ceccarelli, Soledad; Balsalobre, Agustín; Medone, Paula; Cano, María Eugenia; Gurgel Gonçalves, Rodrigo; Feliciangeli, Dora; Vezzani, Darío; Wisnivesky-Colli, Cristina; Gorla, David E.; Marti, Gerardo A.; Rabinovich, Jorge E.

    2018-04-01

    Trypanosoma cruzi, the causative agent of Chagas disease, is transmitted to mammals - including humans - by insect vectors of the subfamily Triatominae. We present the results of a compilation of triatomine occurrence and complementary ecological data that represents the most complete, integrated and updated database (DataTri) available on triatomine species at a continental scale. This database was assembled by collecting the records of triatomine species published from 1904 to 2017, spanning all American countries with triatomine presence. A total of 21815 georeferenced records were obtained from published literature, personal fieldwork and data provided by colleagues. The data compiled includes 24 American countries, 14 genera and 135 species. From a taxonomic perspective, 67.33% of the records correspond to the genus Triatoma, 20.81% to Panstrongylus, 9.01% to Rhodnius and the remaining 2.85% are distributed among the other 11 triatomine genera. We encourage using DataTri information in various areas, especially to improve knowledge of the geographical distribution of triatomine species and its variations in time.

  10. Molecular epidemiology of Trypanosoma cruzi and Triatoma dimidiata in costal Ecuador.

    Science.gov (United States)

    Wong, Yim Yan; Sornosa Macias, Karen Jeniffer; Guale Martínez, Doris; Solorzano, Luis F; Ramirez-Sierra, Maria Jesus; Herrera, Claudia; Dumonteil, Eric

    2016-07-01

    Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. In Ecuador, Triatoma dimidiata and Rhodnius ecuadoriensis are the main vector species, responsible for over half of the cases of T. cruzi infection in the country. T. dimidiata is believed to have been introduced in Ecuador during colonial times, and its elimination from the country is thus believed to be feasible. We investigated here the molecular ecology of T. dimidiata and T. cruzi in costal Ecuador to further guide control efforts. Analysis of the Internal Transcribed Spacer 2 (ITS-2) of 23 specimens from Progreso, Guayas, unambiguously supported the likely importation of T. dimidiata from Central America to Ecuador. The observation of a very high parasite infection rate (54%) and frequent feeding on humans (3/5) confirmed a continued risk of transmission to humans. All genotyped parasites corresponded to TcI DTU and Trypanosoma rangeli was not detected in T. dimidiata. TcI subgroups corresponded to TcIa (25%), and mixed infections with TcIa and TcId (75%). Further studies should help clarify T. cruzi genetic structure in the country, and the possible impact of the introduction of T. dimidiata on the circulating parasite strains. The elevated risk posed by this species warrants continuing efforts for its control, but its apparent mobility between peridomestic and domestic habitats may favor reinfestation following insecticide spraying. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Revisiting Trypanosoma rangeli Transmission Involving Susceptible and Non-Susceptible Hosts.

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    Luciana de Lima Ferreira

    Full Text Available Trypanosoma rangeli infects several triatomine and mammal species in South America. Its transmission is known to occur when a healthy insect feeds on an infected mammal or when an infected insect bites a healthy mammal. In the present study we evaluated the classic way of T. rangeli transmission started by the bite of a single infected triatomine, as well as alternative ways of circulation of this parasite among invertebrate hosts. The number of metacyclic trypomastigotes eliminated from salivary glands during a blood meal was quantified for unfed and recently fed nymphs. The quantification showed that ~50,000 parasites can be liberated during a single blood meal. The transmission of T. rangeli from mice to R. prolixus was evaluated using infections started through the bite of a single infected nymph. The mice that served as the blood source for single infected nymphs showed a high percentage of infection and efficiently transmitted the infection to new insects. Parasites were recovered by xenodiagnosis in insects fed on mice with infections that lasted approximately four months. Hemolymphagy and co-feeding were tested to evaluate insect-insect T. rangeli transmission. T. rangeli was not transmitted during hemolymphagy. However, insects that had co-fed on mice with infected conspecifics exhibited infection rates of approximately 80%. Surprisingly, 16% of the recipient nymphs became infected when pigeons were used as hosts. Our results show that T. rangeli is efficiently transmitted between the evaluated hosts. Not only are the insect-mouse-insect transmission rates high, but parasites can also be transmitted between insects while co-feeding on a living host. We show for the first time that birds can be part of the T. rangeli transmission cycle as we proved that insect-insect transmission is feasible during a co-feeding on these hosts.

  12. New World species of the genus Calliscelio Ashmead (Hymenoptera, Platygastridae, Scelioninae

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    Hua-yan Chen

    2017-01-01

    Full Text Available The genus Calliscelio Ashmead is presumed to be a diverse group of parasitoids of the eggs of crickets (Orthoptera: Gryllidae. A least one species has been found to be an important factor in depressing cricket pest populations. The New World species of Calliscelio are revised. Forty-two species are recognized, 3 are redescribed: C. bisulcatus (Kieffer, C. laticinctus Ashmead, C. rubriclavus (Ashmead, comb. n.; and 38 are described as new: C. absconditum Chen & Johnson, sp. n., C. absum Chen & Johnson, sp. n., C. alcoa Chen & Masner, sp. n., C. amadoi Chen & Johnson, sp. n., C. armila Chen & Masner, sp. n., C. bidens Chen & Masner, sp. n., C. brachys Chen & Johnson, sp. n., C. brevinotaulus Chen & Johnson, sp. n., C. brevitas Chen & Johnson, sp. n., C. carinigena Chen & Johnson, sp. n., C. crater Chen & Johnson, sp. n., C. crena Chen & Johnson, sp. n., C. eboris Chen & Johnson, sp. n., C. extenuatus Chen & Johnson, sp. n., C. flavicauda Chen & Johnson, sp. n., C. foveolatus Chen & Johnson, sp. n., C. gatineau Chen & Johnson, sp. n., C. glaber Chen & Masner, sp. n., C. granulatus Chen & Masner, sp. n., C. latifrons Chen & Johnson, sp. n., C. levis Chen & Johnson, sp. n., C. longius Chen & Johnson, sp. n., C. magnificus Chen & Masner, sp. n., C. migma Chen & Johnson, sp. n., C. minutia Chen & Johnson, sp. n., C. paraglaber Chen & Johnson, sp. n., C. pararemigio Chen & Masner, sp. n., C. prolixus Chen & Johnson, sp. n., C. punctatifrons Chen & Johnson, sp. n., C. remigio Chen & Masner, sp. n., C. ruga Chen & Johnson, sp. n., C. rugicoxa Chen & Masner, sp. n., C. sfina Chen & Johnson, sp. n., C. storea Chen & Johnson, sp. n., C. suni Chen & Johnson, sp. n., C. telum Chen & Johnson, sp. n., C. torqueo Chen & Johnson, sp. n., C. virga Chen & Johnson, sp. n. Four species are treated as junior synonyms of Calliscelio rubriclavus (Ashmead: Anteris nigriceps Ashmead, syn. n., Caloteleia marlattii Ashmead, syn. n., Caloteleia grenadensis Ashmead, syn. n

  13. Sumarliði R. Ísleifsson og Þórunn Sigurðardóttir (ritstjórar: Samfélagsleg áhrif verkalýðshreyfingarinnar á 20. öld - framtíðarsýn á 21. öldinni

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    Guðmundur Heiðar Frímannsson

    2007-06-01

    Full Text Available Tuttugasta öldin var merkileg um margt, sérstaklega fyrir einkennilega blöndu framfara, bætts mannlífs og ótrúlegrar mannvonsku. Frægustu dæmin um mannvonskuna eru heimsstyrjaldirnar tvær, stjórnmálastefnurnar kommúnismi og nasismi og stjórnmálamennirnir Hitler og Stalín. Fleira mætti nefna til að sýna fram á að myndin er ekki svart-hvít. Þekktustu dæmin um framfarirnar eru vísindin, kenningar Einsteins í eðlisfræði, uppgötvun erfðaefnisins og framfarir í læknisfræði. En það er einnig sérstök ástæða til að nefna framfarir í hagfræði og stjórnvísindum og raunar víða í félagsvísindum því að sú grein gleymist gjarnan þegar hugsað er um vísindi: Við skiljum sum samfélagsfyrirbrigði betur nú en fyrir hundrað árum. Gífurlegar tæknilegar framfarir urðu á tuttugustu öldinni og fjöldamörg samfélög heimsins urðu auðug og gerðu venjulegu fólki auðveldara að lifa af; raunar ekki einvörðungu að lifa af heldur að lifa lífi sem það gat stjórnað og var fjölbreyttara og ánægjulegra en líf forfeðra þeirra.

  14. Effects of Population Density and Host Availability on The Migration Process of Brown Planthopper Fed Using Susceptible and Resistant Rice Varieties

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    Imam Habibi

    2016-12-01

    Full Text Available Brown planthopper, Nilaparvata lugens Stal. (Hemiptera: Delphacidae, is an important pest of rice. This pest can cause hopperburn and field failure. This research aimed to determine the effects of population density and host availability on migration of N. lugens. The criteria used to justify the effects of host availability and population density on migration of N. lugens were based the hardness and tannin tests of the rice stems, fecundity of N. lugens, and the life cycle of N. lugens. The research was conducted under the temperature of 29.42°C with relative humidity of 61% and Light 12: Dark 12 times, using ten pairs of N. lugens brachypterous (F0 constant and then was added with five male adults on fifth days after the first infestation (F0 changed. The varieties used were IR64, as a resistant variety, and Ketan Lusi, as a susceptible variety. The results showed that the adding of the macropterous males did not affect the number of macropterous, because of that has been preplanned by the F0. Therefore, the percentage of existing macropterous was 51−52%.   INTISARI   Wereng Batang Cokelat (WBC merupakan salah satu hama tanaman padi yang sangat penting. Kerusakan parah dapat menyebabkan hopperburn dan puso (gagal panen. Tujuan penelitian ini adalah mengetahui pengaruh kepadatan populasi dan tanaman inang sebagai tempat migrasi WBC. Parameter yang dikaji untuk mengetahui pengaruh kepadatan populasi WBC dan tanaman inang tempat migrasi WBC berdasarkan tingkat kekerasan dan kandungan tanin batang tanaman padi, fekunditas WBC, dan siklus hidup WBC. Penelitian ini dilakukan pada temperatur 29.42˚C dengan kelembapan relatif 61% dan durasi siang hari 12 jam: durasi malam hari 12 jam. Metode yang dilakukan adalah dengan menggunakan 10 pasang imago WBC brakhiptera (F0 konstan, kemudian dilakukan penambahan 5 ekor imago jantan pada hari kelima setelah infestasi awal (F0 diubah. Varietas padi yang digunakan yaitu padi varietas IR64 sebagai varietas

  15. “Quit stalling…!”: Destiny and Destination on L.A.’s Inner City Roads

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    Martin Zeilinger

    2009-12-01

    Full Text Available If driving has today really become a Western "metaphor for being" (Hutchinson, then common roadside signs proclaiming "Right lane must exit" or "Through traf-fic merge left", inventions such as the automatic transmission, and the agreeable straightness of freeways can all be understood as symptoms of an ongoing socio-political struggle between the driver as democratic agent, and the state as institu-tionalized regulatory force. Nowhere is this more obvious than in the context of urban traffic, where private motorized transportation represents both the supreme (if illusory expression of personal freedom, and official efforts to channel indivi-dualism by obliterating its sense of direction and ideological divergence. On the concrete proving grounds of the clogged inner-city freeway, "nomad science" and "state science" (Deleuze & Guattari thus oscillate between the pseudo-liberatory expressivity of mainstream car culture and the self-effacing dromoscopic "amne-sia of driving" (Baudrillard. Are a city's multitudes of cars resistant "projectiles" (Virilio or, rather, hegemonic "sites of containment" (Jane Jacobs? This essay approaches the complex tensions between "untamable" democratic mobility and state-regulated transit by way of two Hollywood-produced films that focus on traffic in Los Angeles: in Collateral (2004, a cab driver comes to recognize and transcend the hopelessly directionless circularity dictated by his job; in Falling Down (1993, a frustrated civil service employee abandons his car on a rush-hour freeway and decides to walk home, forced to traverse the supposedly unwalkable city without the "masking screen of the windshield" (Virilio. As they "quit stal-ling", both protagonists become dangerous variants of the defiant nomad - one a driver who remains on the road but goes "under the radar", the other a transient pedestrian whose movement becomes viral and unpredictable. My analysis of the films' metropolitan setting and of the

  16. INTERNATIONAL SURVEY OF PUBLICATIONS IN INTERNATIONAL BUSINESS: RISING THROUGH THE BASE OF WEB SCIENCE

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    Aletéia de Moura Carpes

    2011-06-01

    Full Text Available Internationalization is an alternative to business growth, allowing its exposure to international standards of products, technologies and management methods, generating significant returns for domestic transactions (STAL, 2010. The evolution of commercial transactions between the countries have brought a lot of issues to be understood, that seek to check the reflection of international activity in the individual, company and nation experiencing this context of globalization. This article was developed from the perspective of a bibliometric research, aiming to increase awareness in the study area related to International Business (International Business and determine which topics studied by the administration on this issue are being investigated further and which are most relevant (hot topics. Analysis of data held on the approaches of qualitative and quantitative research. Qualitatively analyzed the issues addressed in the publications surveyed regarding the content, keywords and relevance of topics. As regards the figures sought to investigate the following variables: total number of publications, authors, subject areas, types of documents, the sources title, year of publications, institutions, funding agencies, languages, countries and analysis of the number of times each publication was cited by the hb index and the index m. According to Hirsch (2005, the total number of articles published measures the productivity of the author, but does not measure the importance and / or impact of their publications. Already the impact of publications is measured by the number of citations that each one receives can be measured by the h-index. The survey of publications housed in the Web of Science citation index with the ISI Citation Indexes from 1997 to 2010 (14 years resulted in 5,355 jobs related to international business, which were entered, especially in the areas of business (business and management (management and the studies analyzed showed a

  17. Współczesna architektura drewniana w poszukiwaniu formy swobodnej

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    Michał Golański

    2017-12-01

    Full Text Available Kształtowanie nowoczesnej architektury zgodnej z założeniami zrównoważonego rozwoju wymaga zintegrowanego i synergicznego projektowania zarówno w przypadku noworealizowanych budynków jak i w modernizacji istniejących. Obiekty budowlane powinny wykazywać się nie tylko estetyką, funkcjonalnością i trwałością, lecz również w sposób nieszkodliwy oddziaływać na środowisko, być ekonomicznymi w zużyciu materiałów i energii oraz uwzględniać wszelkie ryzyka z punktu widzenia życia i zdrowia ludzkiego. Drewno, które należy do najstarszych materiałów budowlanych używanych przez człowieka obecne jest w środowisku zabudowanym od początku historii architektury. Modernizm charakteryzował się stopniowym wypieraniem drewna przez inne materiały budowlane: ceramikę, beton i stal. Fizyczne właściwości, łatwość kształtowania i nieskomplikowany proces produkcji w połączeniu z wyjątkowym potencjałem ekologicznym drewna sprawiają, że po okresie względnego regresu konstrukcje drewniane znów stosowane są na dużą skalę. Kreowanie form złożonych w architekturze współczesnej oraz rozwój cyfrowych narzędzi projektowania sprzęgniętych z komputerową technologią obróbki drewna sprawiają, że projektanci uzyskali nowe możliwości kształtowania obiektów architektonicznych. Architektura krzywoliniowa o swobodnej geometrii (free form design odrzuca kartezjańską geometrię i konwencjonalny język brył euklidesowych. Niniejszy artykuł analizuje obiekty architektoniczne charakteryzujące się formami krzywoliniowymi oraz zastosowaniem drewna jako budowlanego materiału konstrukcyjnego.

  18. Detection of Trypanosoma cruzi and Trypanosoma rangeli infection in triatomine vectors by amplification of the histone H2A/SIRE and the sno-RNA-C11 genes Detecção da infecção por Trypanosoma cruzi e Trypanosoma rangeli em vetores triatomíneos através da amplificação dos gens de histona H2A/SIRE e sno-RNA-C11

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    Paula Ximena Pavia

    2007-02-01

    Full Text Available Trypanosoma rangeli is non pathogenic for humans but of important medical and epidemiological interest because it shares vertebrate hosts, insect vectors, reservoirs and geographic areas with T. cruzi, the etiological agent of Chagas disease. Therefore, in this work, we set up two PCR reactions, TcH2AF/R and TrFR2, to distinguish T. cruzi from T. rangeli in mixed infections of vectors based on amplification of the histone H2A/SIRE and the small nucleolar RNA Cl1 genes, respectively. Both PCRs were able to appropriately detect all T. cruzi or T. rangeli experimentally infected-triatomines, as well as the S35/S36 PCR which amplifies the variable region of minicircle kDNA of T. cruzi. In mixed infections, whereas T. cruzi DNA was amplified in 100% of samples with TcH2AF/R and S35/S36 PCRs, T. rangeli was detected in 71% with TrF/R2 and in 6% with S35/S36. In a group of Rhodnius colombiensis collected from Coyaima (Colombia, T. cruzi was identified in 100% with both PCRs and T. rangeli in 14% with TrF/R2 and 10% with S35/S36 PCR. These results show that TcH2AF/R and TrF/R2 PCRs which are capable of recognizing all T. cruzi and T. rangeli strains and lineages could be useful for diagnosis as well as for epidemiological field studies of T. cruzi and T. rangeli vector infections.Embora o Trypanosoma rangeli não seja patogênico para o homem, sua importância médica e epidemiológica reside no fato de compartilhar vetores, reservatórios e áreas geográficas com o Trypanosoma cruzi, agente causal da Doença de Chagas. Neste estudo, para distinguir T. cruzi de T. rangeli em vetores com infecções mistas, se utilizaram duas amplificações de PCR; TcH2AF/R para o gen da histona H2A/SIRE e TrFR2, para um gen repetitivo de ARN nucleolar Cl1 (sno-RNA-Cl1. Assim como a PCR S35/S36, ambas as reações foram capazes de detectar corretamente a presença de T. cruzi ou T. rangeli em triatomíneos infectados experimentalmente. Nas infecções mistas, o ADN de

  19. Estudo anatômico e morfométrico dos folículos testiculares de algumas espécies de Triatominae (Hemiptera: Reduviidae Anatomic and morphometric studies of testicular follicles of some species of Triatominae

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    Teresa Cristina M. Gonçalves

    1987-12-01

    Full Text Available Os folículos testiculares nas ordens dos insetos, vêm demonstrando papel relevante sob o ponto de vista da Sistemática e Filogenia. Nos triatomíneos, os folículos testiculares são em número de sete, sendo que o comprimento e a espesura variam consideravelmente entre os gêneros, e pouco entre as espécies. Verificou-se que em Rhodnius spp existem dois folículos longos e grossos e cinco curtos e fuinnos; em Triatoma spp existem dois longos e finos, dois médios e grossos e três curtos e finos; e em Panstrongylus spp existem sete aproximadamente iguais. Através das medições do comprimento dessas estruturas, evidenciou-se que os valores das médias e desvios padrão das médias, foram muito próximos entre as espécies do mesmo gênero, tornando-se inviável estabelecer limites que pudessem caracterizá-las. Em busca de resultados mais precisos, fizeram-se comparações interespecíficas através da análise de variância: entre as diferentes espécies do mesmo gênro (comparação simultânea; entre cada duas espécies do mesmo gênro (comparação aos pares; e entre espécies iguais de procedência diferentes. Os resultados obtidos não demostraram possibilidades de utilização na Sistemática, contudo foram promissores no que concerne à Filogenia, desde que seja observado um número maior de espécies.The testicular follicle in the varous insect orders, has given evidence of relevance from the point of view of Systematics ans Phylogeny. In the triatomines, the testicular follicles are in number of seven, their lenght and thickness ranging considerabley between the genera and with less variation between the species. It was observed that in Rhodnius spp there exist two long and thick follicles and five short and thin; in Triatoma spp there extist two long and thick, two medium and thick and three short and thin; and in Panstrongylus spp seven, almost identical. Through the measurements of length of these structures, it was observed

  20. Aspectos ecológicos da tripanossomose americana: II - distribuição e dispersão local de triatomíneos em ecótopos naturais e artificiais Ecological aspects of South American tripanosomiasis: II - local distribution and dispersion of triatomids in natural and artificial ecotopes

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    Oswaldo Paulo Forattini

    1971-12-01

    Full Text Available São apresentados os resultados de investigação destinada a estabelecer o quadro de distribuição de Triatoma sordida e Rhodnius neglectus em áreas com ecótopos naturais e artificiais. Essa distribuição revelou-se do tipo agrupado ou contagiante, dirigida uniformemente para casas e anexos por parte do primeiro, e para palmeiras por parte do segundo. Em áreas de vegetação mais densa, do tipo cerrado, a densidade é praticamente nula ou muito baixa, admitindo-se que isso deva correr por conta da competição. As modificações introduzidas pelo homem tendem a anular êsse fator, além de, as suas habitações, se transformarem em ecótopos que atraem a população de T. sordida. Êsse fato, aliado à eliminação local do T. infestans, parece explicar a tendência invasiva daquele triatomíneo. Evidenciou-se também a persistência da infecção pelo Trypanosoma cruzi em triatomíneos e vertebrados domiciliados, o que representa potencial para o incremento da transmissão.A local distribution pattern of Triatoma sordida and Rhodnius neglectus is described after an intensive investigation on natural and artificial ecotopes. The work was carried in a region at north of the State of São Paulo, Brazil. Measures of dispersion pattern were made by the Morisita's indices showing contagious distributions to both bugs. The T. sordida population was clumped at houses and surrounding dwellings, while R. neglectus presented the same aspect but relater to palm trees. The first bug showed ubiquity patter including palms, dry trees and fences. These last two situations are not favourable for obtaining blood meals, who are much more easy obtained at human dwellings. By other side, the investigations at areas with more dense vegetation like bush, resulted in very few T. sordida and none R. neglectus, probably owing of other populations competition as predators reduvids bugs, found there with great density. So it seems logic remove that competition and

  1. Prevalência, índices de infecção e hábitos alimentares de triatomíneos capturados em uma área de vigilância epidemiológica

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    Vera Lúcia C. Corrêa Rodrigues

    1992-09-01

    Full Text Available Em continuação a estudo anterior, relativo à prevalência e infecção por Trypanosoma cruzi dos triatomíneos capturados na região administrativa de Campinas, SP, os autores apresentam dados do período de 1982-1986, acrescentando informações sobre respastos sangüíneos realizados por 7.785 exemplares. Para tanto, foram utilizados os anti-soros: ave, marsupial, roedor e humano, através dos quais constataram o ecletismo alimentar de Panstrongylus megistus, espécie predominante na região, cujas formas aladas são encontradas com freqüência, infectadas por T. cruzi, nas casas habitadas. Desses, 14,78% reagiram frente ao anti-soro humano. Com Rhodnius neglectus foi observada situação assemelhada, mas com números menos expressivos. Em relação ao Triatoma sórdida, não foi constatada infecção natural e tampouco sinais de ingestão de sangue humano. Foi constatado acentuado aumento de T. arthurneivai nas casas, fruto da provável modificação ocorrida no ambiente natural. No período, foi encontrado Microtiatoma borbai, detectado pela primeira vez no Estado de São Paulo. Ressaltam também a importância da "investigação de foco " nas áreas em fase de vigilância.

  2. Aspects of peridomiciliary ecotopes in rural areas of Northeastern Brazil associated to triatomine (Hemiptera, Reduviidae infestation, vectors of Chagas disease

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    Otília Sarquis

    2006-03-01

    Full Text Available Artificial ecotopes of 121 peridomiciliary environments in four rural localities in the state of Ceará, Brazil, were studied and the type of material of the ecotopes was identified as triatomine infestation. Two thousand two hundred and four Triatoma brasiliensis Neiva, 340 Triatoma pseudomaculata Corrêa and Espínola, 121 Rhodnius nasutus Stall, and 5 Panstrongylus lutzi (Neiva and Pinto were captured. Out of the 323 ecotopes found (X =2.0 ± 1.8 per dwelling such as pigpens, henhouses, corrals, perches, dovecotes, piles of roofing tiles, bricks, wood, and straw 30.3% were infested by triatomines in all different developmental stages, including eggs. A substantial number of triatomines were found in perches, however the largest infestation took place in roofing materials used in the construction of goat/sheep corrals, henhouses, and pigpens, where 98% of them were captured: 1372 triatomines were located in the roofing tile covers, 285 in the straw, 187 in the perches, 77 in the coverings of roofing tiles and straw, and 13 in the straw and wood. Among all the different pile of materials, roofing tiles were the most infested (50% followed by bricks (38.9% and woods (36.1%. T. brasiliensis colonized mainly brick piles (chi2=16.539; p < 0.05 and roofing tiles (chi2=5,090.58; p < 0.05; T. pseudomaculata preferred wood perches (chi2= 472.39; p < 0.05 and woodpiles (chi2=126.0 p < 0.05, and R. nasutus was principally found in roofing straw (chi2=384.43; p < 0.05. These findings suggest that triatomines tend to colonize peridomiciliary ecotopes similar to their original habitats.

  3. Trypanosoma cruzi IV causing outbreaks of acute Chagas disease and infections by different haplotypes in the Western Brazilian Amazonia.

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    Wuelton Marcelo Monteiro

    Full Text Available BACKGROUND: Chagas disease is an emergent tropical disease in the Brazilian Amazon Region, with an increasing number of cases in recent decades. In this region, the sylvatic cycle of Trypanosoma cruzi transmission, which constitutes a reservoir of parasites that might be associated with specific molecular, epidemiological and clinical traits, has been little explored. The objective of this work is to genetically characterize stocks of T. cruzi from human cases, triatomines and reservoir mammals in the State of Amazonas, in the Western Brazilian Amazon. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed 96 T. cruzi samples from four municipalities in distant locations of the State of Amazonas. Molecular characterization of isolated parasites from cultures in LIT medium or directly from vectors or whole human blood was performed by PCR of the non-transcribed spacer of the mini-exon and of the 24 S alfa ribosomal RNA gene, RFLP and sequencing of the mitochondrial cytochrome c oxidase subunit II (COII gene, and by sequencing of the glucose-phosphate isomerase gene. The T. cruzi parasites from two outbreaks of acute disease were all typed as TcIV. One of the outbreaks was triggered by several haplotypes of the same DTU. TcIV also occurred in isolated cases and in Rhodnius robustus. Incongruence between mitochondrial and nuclear phylogenies is likely to be indicative of historical genetic exchange events resulting in mitochondrial introgression between TcIII and TcIV DTUs from Western Brazilian Amazon. TcI predominated among triatomines and was the unique DTU infecting marsupials. CONCLUSION/SIGNIFICANCE: DTU TcIV, rarely associated with human Chagas disease in other areas of the Amazon basin, is the major strain responsible for the human infections in the Western Brazilian Amazon, occurring in outbreaks as single or mixed infections by different haplotypes.

  4. Entomological and ecological aspects of six sylvatic species of triatomines (Hemiptera, Reduviidae from the collection of the National Biodiversity Institute of Costa Rica, Central America

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    Rodrigo Zeledón

    2001-08-01

    Full Text Available A total of 797 specimens of wild adult triatomines, belonging to six species from the entomological collections of the Costa Rican National Biodiversity Institute, was studied from the standpoint of their relative abundance, as reflected by light traps, distribution in the country, seasonal variations and climatic and altitudinal preferences. Triatoma dimidiata was the most abundant species (32.9% of the total specimens, with a very extensive distribution in different ecological zones, being more common between 100 to 400 m above sea level mainly at the end of the dry season. T. dispar was the third in frequency (21.5%, with narrower distribution, more abundant between 600 to 800 m and scarce during the dry season. Panstrongylus geniculatus and P. rufotuberculatus, second and fourth in frequency (22.1% and 15.1%, respectively, were widely distributed on both the Pacific and Caribbean basins, the former being more common between 80 to 270 m all year round and the latter below 800 m mainly during the first semester. Eratyrus cuspidatus which represented only 4.9% of the insects, was also present on both basins mainly below 200 m with a tendency to be scarce during certain months of the year, and was found in all types of ecological zones. Finally, Rhodnius pallescens, the least abundant species (3.6% was restricted to very humid areas below 20 m, on the north side and Caribbean basin. With the exception of R. pallescens, males were more commonly found than females. Some epidemiological implications related to the six species are discussed.

  5. Community-Based Entomological Surveillance Reveals Urban Foci of Chagas Disease Vectors in Sobral, State of Ceará, Northeastern Brazil.

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    Cynara Carvalho Parente

    Full Text Available The aim of this work was to explore the potential risk of vector-borne Chagas disease in urban districts in northeastern Brazil, by analyzing the spatiotemporal distributions and natural infection rates with Trypanosoma cruzi of triatomine species captured in recent years. The main motivation of this work was an acute human case of Chagas disease reported in 2008 in the municipality of Sobral.We analyzed data from community-based entomological surveillance carried out from 2010 to 2014. Triatomine natural T. cruzi infection was assessed by examination of insect feces by optical microscopy. Sites of triatomine capture were georeferenced through Google Earth and analyzed with ArcGIS. A total of 191 triatomines were collected, consisting of 82.2% Triatoma pseudomaculata, 7.9% Rhodnius nasutus, 5.8% T. brasiliensis, 3.7% Panstrongylus lutzi, and 0.5% P. megistus, with an overall natural infection index of 17.8%. Most infestations were reported in the districts of Dom José (36.2%, Padre Palhano (24.7%, and Alto do Cristo (10.6%. The overwhelming majority of insects (185/96.9% were captured inside houses, and most insects tended to be collected in intermittent peaks. Moreover, captured triatomines tended to constitute colonies. The acute case reported in 2008 was found to be situated within a T. pseudomaculata hotspot.The triatomine collection events carried out by dwellers were aggregated in time and space into distinct foci, suggesting that insects are intermittently and artificially introduced into the city, possibly via accidental migration from their natural reservoirs. The relatively high T. cruzi infection rate indicates considerable circulation of the parasite in these areas, increasing the risk of vector-borne Chagas disease infection. These data suggest a need to strengthen epidemiological surveillance and integrate appropriate control actions targeting triatomines, T. cruzi reservoirs, and human populations. Our data also identify Chagas

  6. Comprehensive Survey of Domiciliary Triatomine Species Capable of Transmitting Chagas Disease in Southern Ecuador.

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    Grijalva, Mario J; Villacis, Anita G; Ocaña-Mayorga, Sofia; Yumiseva, Cesar A; Moncayo, Ana L; Baus, Esteban G

    2015-01-01

    Chagas disease is endemic to the southern Andean region of Ecuador, an area with one of the highest poverty rates in the country. However, few studies have looked into the epidemiology, vectors and transmission risks in this region. In this study we describe the triatomine household infestation in Loja province, determine the rate of Trypanosoma cruzi infection in triatomines and study the risk factors associated with infestation. An entomological survey found four triatomine species (Rhodnius ecuadoriensis, Triatoma carrioni, Panstrongylus chinai, and P. rufotuberculatus) infesting domiciles in 68% of the 92 rural communities examined. Nine percent of domiciles were infested, and nymphs were observed in 80% of the infested domiciles. Triatomines were found in all ecological regions below 2,200 masl. We found R. ecuadoriensis (275 to 1948 masl) and T. carrioni (831 to 2242 masl) mostly in bedrooms within the domicile, and they were abundant in chicken coops near the domicile. Established colonies of P. chinai (175 to 2003 masl) and P. rufotuberculatus (404 to 1613 masl) also were found in the domicile. Triatomine infestation was associated with surrogate poverty indicators, such as poor sanitary infrastructure (lack of latrine/toilet [w = 0.95], sewage to environment [w = 1.0]). Vegetation type was a determinant of infestation [w = 1.0] and vector control program insecticide spraying was a protective factor [w = 1.0]. Of the 754 triatomines analyzed, 11% were infected with Trypanosoma cruzi and 2% were infected with T. rangeli. To date, only limited vector control efforts have been implemented. Together with recent reports of widespread sylvatic triatomine infestation and frequent post-intervention reinfestation, these results show that an estimated 100,000 people living in rural areas of southern Ecuador are at high risk for T. cruzi infection. Therefore, there is a need for a systematic, sustained, and monitored vector control intervention that is coupled with

  7. Comprehensive Survey of Domiciliary Triatomine Species Capable of Transmitting Chagas Disease in Southern Ecuador.

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    Mario J Grijalva

    Full Text Available Chagas disease is endemic to the southern Andean region of Ecuador, an area with one of the highest poverty rates in the country. However, few studies have looked into the epidemiology, vectors and transmission risks in this region. In this study we describe the triatomine household infestation in Loja province, determine the rate of Trypanosoma cruzi infection in triatomines and study the risk factors associated with infestation.An entomological survey found four triatomine species (Rhodnius ecuadoriensis, Triatoma carrioni, Panstrongylus chinai, and P. rufotuberculatus infesting domiciles in 68% of the 92 rural communities examined. Nine percent of domiciles were infested, and nymphs were observed in 80% of the infested domiciles. Triatomines were found in all ecological regions below 2,200 masl. We found R. ecuadoriensis (275 to 1948 masl and T. carrioni (831 to 2242 masl mostly in bedrooms within the domicile, and they were abundant in chicken coops near the domicile. Established colonies of P. chinai (175 to 2003 masl and P. rufotuberculatus (404 to 1613 masl also were found in the domicile. Triatomine infestation was associated with surrogate poverty indicators, such as poor sanitary infrastructure (lack of latrine/toilet [w = 0.95], sewage to environment [w = 1.0]. Vegetation type was a determinant of infestation [w = 1.0] and vector control program insecticide spraying was a protective factor [w = 1.0]. Of the 754 triatomines analyzed, 11% were infected with Trypanosoma cruzi and 2% were infected with T. rangeli.To date, only limited vector control efforts have been implemented. Together with recent reports of widespread sylvatic triatomine infestation and frequent post-intervention reinfestation, these results show that an estimated 100,000 people living in rural areas of southern Ecuador are at high risk for T. cruzi infection. Therefore, there is a need for a systematic, sustained, and monitored vector control intervention that is

  8. Comprehensive Survey of Domiciliary Triatomine Species Capable of Transmitting Chagas Disease in Southern Ecuador

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    Grijalva, Mario J.; Villacis, Anita G.; Ocaña-Mayorga, Sofia; Yumiseva, Cesar A.; Moncayo, Ana L.; Baus, Esteban G.

    2015-01-01

    Background Chagas disease is endemic to the southern Andean region of Ecuador, an area with one of the highest poverty rates in the country. However, few studies have looked into the epidemiology, vectors and transmission risks in this region. In this study we describe the triatomine household infestation in Loja province, determine the rate of Trypanosoma cruzi infection in triatomines and study the risk factors associated with infestation. Methodology/Principal Findings An entomological survey found four triatomine species (Rhodnius ecuadoriensis, Triatoma carrioni, Panstrongylus chinai, and P. rufotuberculatus) infesting domiciles in 68% of the 92 rural communities examined. Nine percent of domiciles were infested, and nymphs were observed in 80% of the infested domiciles. Triatomines were found in all ecological regions below 2,200 masl. We found R. ecuadoriensis (275 to 1948 masl) and T. carrioni (831 to 2242 masl) mostly in bedrooms within the domicile, and they were abundant in chicken coops near the domicile. Established colonies of P. chinai (175 to 2003 masl) and P. rufotuberculatus (404 to 1613 masl) also were found in the domicile. Triatomine infestation was associated with surrogate poverty indicators, such as poor sanitary infrastructure (lack of latrine/toilet [w = 0.95], sewage to environment [w = 1.0]). Vegetation type was a determinant of infestation [w = 1.0] and vector control program insecticide spraying was a protective factor [w = 1.0]. Of the 754 triatomines analyzed, 11% were infected with Trypanosoma cruzi and 2% were infected with T. rangeli. Conclusions/Significance To date, only limited vector control efforts have been implemented. Together with recent reports of widespread sylvatic triatomine infestation and frequent post-intervention reinfestation, these results show that an estimated 100,000 people living in rural areas of southern Ecuador are at high risk for T. cruzi infection. Therefore, there is a need for a systematic, sustained

  9. Dynamics of sylvatic Chagas disease vectors in coastal Ecuador is driven by changes in land cover.

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    Mario J Grijalva

    2014-06-01

    Full Text Available Chagas disease is a serious public health problem in Latin America where about ten million individuals show Trypanosoma cruzi infection. Despite significant success in controlling domiciliated triatomines, sylvatic populations frequently infest houses after insecticide treatment which hampers long term control prospects in vast geographical areas where vectorial transmission is endemic. As a key issue, the spatio-temporal dynamics of sylvatic populations is likely influenced by landscape yet evidence showing this effect is rare. The aim of this work is to examine the role of land cover changes in sylvatic triatomine ecology, based on an exhaustive field survey of pathogens, vectors, hosts, and microhabitat characteristics' dynamics.The study was performed in agricultural landscapes of coastal Ecuador as a study model. Over one year, a spatially-randomized sampling design (490 collection points allowed quantifying triatomine densities in natural, cultivated and domestic habitats. We also assessed infection of the bugs with trypanosomes, documented their microhabitats and potential hosts, and recorded changes in landscape characteristics. In total we collected 886 individuals, mainly represented by nymphal stages of one triatomine species Rhodnius ecuadoriensis. As main results, we found that 1 sylvatic triatomines had very high T. cruzi infection rates (71% and 2 densities of T. cruzi-infected sylvatic triatomines varied predictably over time due to changes in land cover and occurrence of associated rodent hosts.We propose a framework for identifying the factors affecting the yearly distribution of sylvatic T. cruzi vectors. Beyond providing key basic information for the control of human habitat colonization by sylvatic vector populations, our framework highlights the importance of both environmental and sociological factors in shaping the spatio-temporal population dynamics of triatomines. A better understanding of the dynamics of such socio

  10. Expanding the knowledge of the geographic distribution of Trypanosoma cruzi TcII and TcV/TcVI genotypes in the Brazilian Amazon.

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    Valdirene Dos Santos Lima

    Full Text Available Trypanosoma cruzi infection is a complex sylvatic enzooty involving a wide range of animal species. Six discrete typing units (DTUs of T. cruzi, named TcI to TcVI, are currently recognized. One unanswered question concerning the epidemiology of T. cruzi is the distribution pattern of TcII and hybrid DTUs in nature, including their virtual absence in the Brazilian Amazon, the current endemic area of Chagas disease in Brazil. Herein, we characterized biological samples that were collected in previous epizootiological studies carried out in the Amazon Basin in Brazil. We performed T. cruzi genotyping using four polymorphic genes to identify T. cruzi DTUs: mini-exon, 1f8, histone 3 and gp72. This analysis was conducted in the following biological samples: (i two T. cruzi isolates obtained by culturing of stools from the triatomine species Rhodnius picttipes and (ii five serum samples from dogs in which trypomastigotes were observed during fresh blood examination. We report for the first time the presence of TcII and hybrid DTUs (TcV/TcVI in the Amazon region in mixed infections with TcI. Furthermore, sequencing of the constitutive gene, gp72, demonstrated diversity in TcII even within the same forest fragment. These data show that TcII is distributed in the five main Brazilian biomes and is likely more prevalent than currently described. It is very probable that there is no biological or ecological barrier to the transmission and establishment of any DTU in any biome in Brazil.

  11. The use of radioactive inserts in the study of metal deformation during tube-making processes; Emploi de fils metalliques radioactifs pour l'etude des deformations des metaux pendant la fabrication de tubes; Ispol'zovanie radioaktivnykh vtulok dlya izucheniya deformatsii metallov pri protsesse izgotovleniya trub; Empleo de insertos radiactivos en el estudio de la deformacion de los metales durante la fabricacion de tubos

    Energy Technology Data Exchange (ETDEWEB)

    Davison, W H.T. [Tube Investments Research Laboratories, Cambridge (United Kingdom)

    1962-01-15

    experimental, que es aplicable a los estudios sobre deformacion de los metales en general. En este metodo es preciso localizar el inserto radiactivo con un error no mayor de un milimetro, lo que exige un poder de resolucion superior al que requieren normalmente las tecnicas de exploracion medica. Se examinan los problemas correspondientes en terminos de energia gamma, diseno del colimador y discriminacion de energias. (author) [Russian] V nastoyashchej rabote rassmatrivaetsya vopros ob ispol'zovanii radio- aktivnykh vtulok pri izuchenii deformatsii stali v pirsing-protsesse s pomoshch'yu goryachego rotatsionnogo metoda. ZHeleznaya ili stal'naya provoloka aktiviruetsya v reaktore, pomeshchaetsya v truby, pro- sverlennye v zheleznykh ili stal'nykh zagotovkakh, kotorye zatem podvergayutsya obrabotke v normal'nykh proizvodstvennykh usloviyakh. Tshchatel'noe nablyudenie pokazyvaet, chto radiatsionnoe obluchenie i zagryazneniya ustanovki sovershenno neznachitel'ny. Posle okhlazhdeniya zagotovki podvergayutsya analizu v laboratorii putem primeneniya kollimirovannogo stsintillyatsionnogo schetchika, raspolozhennogo perpendikulyarno k poverkhnosti prosverlennoj zagotovki; krivye izodoz pokazyvayut formu deformiro- vannoj radioaktivnoj vtulki, raspolozhennoj pod pryamym uglom k poverkhnosti truby. Drugoj grafik poluchaetsya ot podobnogo roda razvertki uchastka, nakhodyashchegosya pod pryamym uglom k osi truby; pri pomoshchi dvukh poluchennykh grafikov poluchaetsya kartina v trekh izmereniyakh. V dokumente privodyatsya nekotorye rezul'taty, no osnovnoe vnimanie v nem udelyaetsya metodam provedeniya ehksperimentov, kotorye shiroko ispol'zuyutsya pri izuchenii defor- matsii metallov. Vtulki dolzhny byt' raspolozheny na rasstoyanii millimetra ili okolo ehtogo, dlya chego trebuetsya bolee vysokaya razreshayushchaya sposobnost' po sravneniyu s normal'nymi metodami issledovaniya, primenyaemymi v meditsine. Problemy dostizheniya ehtogo ras- smatrivayutsya v nastoyashchem doklade v zavisimosti

  12. Eficiência de Metarhizium anisopliae no controle do Percevejo-do-Colmo Tibraca limbativentris (Heteroptera: Pentatomidae em lavoura de arroz irrigado Efficiency of Metarhizium anisopliae on rice stem bug Tibraca limbativentris (Heteroptera: Pentatomidae control in flooded rice field

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    José Francisco da Silva Martins

    2004-12-01

    Full Text Available O percevejo-do-colmo, Tibraca limbativentris Stal, 1860 (Heteroptera: Pentatomidae, é altamente prejudicial à cultura do arroz no Brasil, principalmente em sistemas de cultivo irrigados por inundação. O efeito de duas formas de aplicação, conídios em suspensão e veiculados em grãos de arroz autoclavado, da cepa (CP 172 de Metarhizium anisopliae (Metsch. Sorok., no controle do percevejo, foi avaliado em três experimentos conduzidos em 1991, 1993 e 1994, em lavoura comercial de arroz irrigado. Em 1991, tanto a pulverização de conídios como a distribuição manual grãos de arroz cobertos com material fúngico em dosagem equivalente a 7,2 x 10(13 conídios.ha-1, sobre o solo e entre os colmos de arroz, onde os percevejos estavam alojados, reduziram significativamente a população natural do inseto com eficiência de controle de 52,6% e 61,8%, respectivamente. Ainda em 1991, estudo sobre o estabelecimento e persistência da cepa no solo do arrozal, com base na contagem de unidades formadoras de colônias (UFC, indicou que o fungo manteve-se viável na entressafra, até 216 dias após a aplicação, época da implantação de novos arrozais. O número de UFC foi maior nas parcelas tratadas com os grãos de arroz cobertos com material fúngico. O crescimento linear do número de UFC, no solo nas parcelas testemunhas, evidenciou disseminação do fungo para partes anteriormente não tratadas do arrozal. Resultados significativos de controle com a aplicação da suspensão de conídios e dos grãos de arroz com o fungo, na dose de 5 x 10(13 conídios.ha-1, também foram obtidos em 1993, com 51,8% e 48,2% de eficiência, respectivamente. Em 1994, a aplicaç��o da suspensão de 5 x 10(13 conídios.ha-1 resultou em 39,5% de controle do inseto. O índice de confirmação de infeção, contudo, foi baixo, nos dois anos, atingindo, no máximo, 20%, em 1993. O baixo número de insetos com micose, em comparação ao índice de mortalidade

  13. A new endemic focus of Chagas disease in the northern region of Veraguas Province, Western Half Panama, Central America.

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    Azael Saldaña

    Full Text Available BACKGROUND: Chagas disease was originally reported in Panama in 1931. Currently, the best knowledge of this zoonosis is restricted to studies done in historically endemic regions. However, little is known about the distribution and epidemiology of Chagas disease in other rural areas of the country. METHODS AND FINDINGS: A cross-sectional descriptive study was carried out between May 2005 - July 2008 in four rural communities of the Santa Fe District, Veraguas Province. The study included an entomologic search to collect triatomines, bloodmeal type identification and infection rate with trypanosomes in collected vectors using a dot- blot and PCR analysis, genotyping of circulating Trypanosoma cruzi (mini-exon gene PCR analysis and the detection of chagasic antibodies among inhabitants. The vector Rhodnius pallescens was more frequently found in La Culaca and El Pantano communities (788 specimens, where it was a sporadic household visitor. These triatomines presented darker coloration and larger sizescompared with typical specimens collected in Central Panama. Triatoma dimidiata was more common in Sabaneta de El Macho (162 specimens. In one small sub-region (El Macho, 60% of the houses were colonized by this vector. Of the examined R. pallescens, 54.7.0% (88/161 had fed on Didelphis marsupialis, and 24.6% (34/138 of T. dimidiata specimens collected inside houses were positive for human blood. R. pallescens presented an infection index with T. cruzi of 17.7% (24/136, with T. rangeli of 12.5% (17/136 and 50.7% (69/136 were mixed infections. In 117 T. dimidiata domestic specimens the infection index with T. cruzi was 21.4%. Lineage I of T. cruzi was confirmed circulating in these vectors. A T. cruzi infection seroprevalence of 2.3% (24/1,056 was found in this population. CONCLUSIONS: This is the first report of Chagas disease endemicity in Santa Fe District, and it should be considered a neglected public health problem in this area of Panama.

  14. Parasitismo natural de ovos de triatomíneos por Telenomus fariai lima, 1927 no laboratório

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    Alexandre José Fernandes

    1990-09-01

    Full Text Available Em novembro/89 verificou-se que o insetário do Centro de Estudos Emmanuel Dias - Bambuí/MG apresentava alta infestação pelo micro himenóptero Telenomus fariai. Em 529 ovos de Panstrongylus megistus e Triatoma vitticeps examinados, 375 (70,9% apresentavam 1043 exemplares de T. fariai, sendo 955 (91,4% fêmeas e 90 (8,6% machos. A seguir, verificou-se também oparasitismo de ovos de Triatoma infestans, e ausência de infestação de ovos de Rhodnius neglectus. As médias de parasitóide por ovo observadas foram de 7,9 em P. megistus; 8,7 em T. vitticeps e 10 em T. infestans. A importância do relato deve-se à possibilidade da infestação de colônias mantidas para fins de pesquisa a partir da introdução em insetários de ovos procedentes do campo, com o estabelecimento de altas taxas de infestação e acentuado declínio da criação. O isolamento e a eliminação dos parasitóides pelo manejo dos ovos parasitados e vedação dos frascos do insetário com tecido de malha estreita (em tomo de 0,25mm mostraram-se eficientes no controle do T. fariai.In november/89 in the insectary of Centro de Estudos "Emmanuel Dias"/Bambui-MG a high infestation by the microhymenoptera T. fariai was found. Among the 529 eggs examined from P. megistus and T. vitticeps, 375(70.9% of them showed a total of1045parasites (91.4% females and 8.6% males. Later on it was found that T. infestans eggs were also parasitised by T. fariai but not those from R. neglectus. The observedparasitoid/egg average was 7.9 in P. megistus; 8.7 in T. vitticeps and 10 in T. infestans. The present report has special importance considering the real possibility ofT. fariai infestation due to the access of infested triatomine eggs from field captures inducing great damage to colonies maintainedfor research purposes. These eggs have to be carefully examined, isolated and eliminated. This procedure and the closing of triatomine containers with thin net (0.25 mm is show to be efficient in T

  15. Infestation of Palm Trees by Triatomines (Hemiptera: Reduviidae in the State of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Gurgel-Gonçalves

    2012-12-01

    Resumo. As palmeiras desempenham papéis importantes como habitats de reprodução e alimentação para triatomíneos silvestres, vetores da doença de Chagas. A ocorrência de triatomíneos em palmeiras peridomiciliares pode aumentar o risco de invasão desses insetos em domicílios e deve ser considerada para desenvolver estratégias de prevenção. Com objetivo de investigar a infestação de palmeiras por triatomíneos no Estado da Bahia e determinar a infecção natural desses insetos por Trypanosoma spp., foram amostradas 183 palmeiras em 12 municípios entre 2006 e 2011 utilizando captura manual e/ou armadilhas adesivas iscadas com camundongos. Os triatomíneos foram detectados em 79 palmeiras (43% das espécies Copernicia prunifera (Mart. Becc., Mauritia flexuosa L. e Attalea spp. (Attalea burretiana Bondar ou Attalea salvadorensis Glassman. Em outras espécies de palmeiras (Syagrus coronata (Mill H.E. Moore, Attalea funifera Mart ex. Spreng e Elaeis guineensis Jacq não foram detectados triatomíneos. Rhodnius neglectus Lent, Triatoma sordida (Stål, e Triatoma pseudomaculata Corrêa & Espínola ocorreram em C. prunifera ao longo do rio São Francisco. No extremo oeste da Bahia, R. neglectus e Psammolestes tertius Lent & Jurberg foram detectados em M. flexuosa, enquanto Triatoma tibiamaculata (Pinto ocorreu em Attalea sp. em áreas urbanas de Salvador. No total, 180 triatomíneos foram capturados, principalmente R. neglectus. A maior taxa de infecção natural (61% foi observada em T. tibiamaculata. Os resultados indicam que pelo menos três espécies de palmeiras são habitats favoráveis para triatomíneos no estado da Bahia e ocorrem no ambiente peridomiciliar, o que pode aumentar a probabilidade de invasão de triatomíneos nas casas.

  16. Enfermedad de chagas en la Región Nororiental del Perú. I. Triatominos (Hemiptera, Reduviidae presentes en Cajamarca y Amazonas

    Directory of Open Access Journals (Sweden)

    Abraham G Cáceres

    2002-01-01

    Full Text Available Objetivos: Conocer la diversidad de triatominos presentes en las provincias de San Ignacio y Jaén (Cajamarca y en Bagua, Condorcanqui y Utcubamba (Amazonas. Materiales y métodos: los triatominos fueron capturados de mayo 1995 a diciembre 2000 en el intra y peridomicilios de las viviendas de las provincias de San Ignacio (5 distritos y Jaén (10 distritos del departamento de Cajamarca, y en 5 distritos de Bagua, un distrito de Condorcanqui y en seis de Utcubamba (Amazonas. El muestreo fue de 08:00 a 19:00 horas con alambre de 30 cm de largo, pinzas largas y linterna de mano. Resultados: se capturaron 5567 triatominos pertenecientes a cinco especies. Panstrongylus herreri fue la especie más predominante (94%. 90% del total de triatominos fueron capturados en ambientes intradomiciliarios. Se reporta Rhodnius robustus por primera vez para Amazonas. Ejemplares de R. ecuadoriensis y R. robustus, fueron colectados en intradomicilios en porcentajes mínimos en Sallique, provincia de Jaén (Cajamarca y Nieva, provincia de Condorcanqui (Amazonas. Panstrongylus geniculatus fue colectado en intradomicilios. Se reporta en ciertas localidades de La Coipa, Huarango y Namballe (San Ignacio; así como en Bellavista y Santa Rosa (Jaén y en Aramango, Copallín e Imaza (Bagua; además, en Jamalca, Cajaruro y Bagua Grande (Utcubamba. Panstrongylus chinai, especie silvestre con tendencia a domesticarse, se encontró en Santa Rosa, Bellavista, Chontalí y San José del Alto (Jaén y en Namballe, San Ignacio, La Coipa y Chirinos (San Ignacio. También se encontró en Cajaruro y Bagua Grande (Utcubamba. 90% de P. herreri fueron colectados en el interior de las viviendas. Para Cajamarca se ha colectado en Pomahuaca, Pucará, San José del Alto, Pirias, Bellavista, Santa Rosa, La Coipa y Huarango; mientras que para Amazonas en Aramango, Parco, Bagua Grande, Cajaruro y El Milagro.

  17. Triatominae-Trypanosoma cruzi/T. rangeli: Vector-parasite interactions.

    Science.gov (United States)

    Vallejo, G A; Guhl, F; Schaub, G A

    2009-01-01

    subpathogenic for the insect host, T. rangeli strongly affects species of the genus Rhodnius and this pathogenicity seems based on a reduction of the number of symbionts.

  18. Preparation, characterization, and safety evaluation of poly(lactide-co-glycolide nanoparticles for protein delivery into macrophages

    Directory of Open Access Journals (Sweden)

    Guedj AS

    2015-09-01

    Full Text Available Anne-Sophie Guedj,1 Arnold J Kell,2 Michael Barnes,2 Sandra Stals,1 David Gonçalves,3 Denis Girard,3 Carole Lavigne11National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, 2National Research Council of Canada, Ottawa, ON, 3Laboratoire de recherche en inflammation et physiologie des granulocytes, Université du Québec, INRS-Institut Armand-Frappier, Laval, QC, CanadaAbstract: Following infection, HIV establishes reservoirs within tissues that are inaccessible to optimal levels of antiviral drugs or within cells where HIV lies latent, thus escaping the action of anti-HIV drugs. Macrophages are a persistent reservoir for HIV and may contribute to the rebound viremia observed after antiretroviral treatment is stopped. In this study, we further investigate the potential of poly(lactic-co-glycolic acid (PLGA-based nanocarriers as a new strategy to enhance penetration of therapeutic molecules into macrophages. We have prepared stable PLGA nanoparticles (NPs and evaluated their capacity to transport an active molecule into the human monocyte/macrophage cell line THP-1 using bovine serum albumin (BSA as a proof-of-concept compound. Intracellular localization of fluorescent BSA molecules encapsulated into PLGA NPs was monitored in live cells using confocal microscopy, and cellular uptake was quantified by flow cytometry. In vitro and in vivo toxicological studies were performed to further determine the safety profile of PLGA NPs including inflammatory effects. The size of the PLGA NPs carrying BSA (PLGA-BSA in culture medium containing 10% serum was ~126 nm in diameter, and they were negatively charged at their surface (zeta potential =-5.6 mV. Our confocal microscopy studies and flow cytometry data showed that these PLGA-BSA NPs are rapidly and efficiently taken up by THP-1 monocyte-derived macrophages (MDMs at low doses. We found that PLGA-BSA NPs increased cellular uptake and internalization of the protein in vitro. PLGA

  19. Facilities for Waste Management at Chalk River, Canada; Les Installations d'Elimination et d'Utilisation des Dechets a Chalk River, Canada; 041e 0411 041e 0420 0423 0414 041e 0412 ; Instalaciones Utilizadas para el Provechamiento y Evacuacion de Desechos Radiactivos en Chalk River, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Mawson, C. A.; Russell, A. E. [Environmental Research Branch, Atomic Energy of Canada Ltd. (Canada)

    1960-07-01

    rio Ottawa. Los efluentes liquidos de baja actividad se evacuan en pozos cavados en la arena, que se llenan con rocas de pequeno tamano a fin de impedir que los liquidos entren en contacto con el aire. Los liquidos de actividad media se mezclan con cemento en tambores que se apilan y entierran totalmente en zanjas de hormigon, mientras que los solidos de actividad media se introducen en zanjas revestidas de hormigon. Por su parte, los solidos de elevada actividad se colocan en hoyos revestidos de acero o de tubos de hormigon. Se emplean instalaciones especiales para los liquidos organicos y los desechos envasados. Los autores dan detalles sobre los trabajos de construccion de esas instalaciones y sobre los procedimientos de evacuacion utilizados y describen sucintamente los resultados del monitoraje del medio ambiente. (author) [Russian] Punkty udalenija othodov, ispol'zuemye Kanadskim ob{sup e}dineniem po atomnoj jenergii, raspolozheny v kamennom bassejne, zapolnjaemym valunnoj glinoj i peskom, kotorye spuskajutsja v reku Ottava. Maloaktivnyj zhidkij jefljuent pomeshhaetsja v jamy, vyrytye v peske, kotorye napolneny nebol'shimi kamnjami, chtoby predotvratit' kontakt zhidkosti s vozduhom. Zhidkij jefljuent srednej aktivnosti smeshivaetsja s cementom v barabanah, kotorye slozheny v shtabelja i zashhishheny betonirovannymi rvami; tverdye tela srednej aktivnosti pogruzhajutsja v betonirovannye rvy; tverdye tela bol'shoj aktivnosti pomeshhajutsja v jamy, vylozhennye stal'nymi i betonnymi trubami. Dlja organicheskih zhidkostej i othodov, zakljuchennyh v butylki, primenjaetsja special'noe oborudovanie. V dokumente budut podrobno opisany ustrojstvo oborudovanija i process proizvodstva, i budut privedeny rezul'taty kontrolja okruzhajushhej sredy. (author)

  20. Wear studies in the shearing process by means of irradiated tools; Etudes d'usure dans les operations de cisaillement, au moyen d'outils irradies; Issledovaniya problemy iznosa v protsesse skalyvaniya posredstvom obluchennykh instrumentov; Estudios de desgaste en las operaciones de cizallamiento, realizados con ayuda de herramientas irradiadas

    Energy Technology Data Exchange (ETDEWEB)

    Sata, Toshio; Abe, Kunio; Nakajima, Kiyoshi [Institute of Physical and Chemical Research, Komagome, Bunkyo-Ku, Tokyo (Japan)

    1962-01-15

    del punzon y de la matriz al emplear lubricantes y laminas metalicas de distintos tipos, obteniendose los resultados siguientes: 1) Al comienzo de la operacion, los indices de desgaste del punzon y de la matriz son muy elevados, pero disminuyen rapidamente, para estabilizarse despues de haber recortado entre 400 y 500 piezas; 2) El desgaste del punzon supera en un 20 por ciento al de la matriz; 3) Los lubricantes con aditivos especiales para altas presiones (compuestos de cloro, fosforo o azufre) reducen el desgaste de las herramientas, mientras que los aceites minerales refinados ejercen poco efecto; 4) Cuanto mas duro es el metal trabajado, tanto mayor es el desgaste de las herramientas; el desgaste al punzonar acero inoxidable y acero al silicio es tres y seis veces superior, respectivamente, al observado en el caso del acero pobre en carbono. (author) [Russian] Iznos instrumenta v protsesse skalyvaniya metallicheskogo lista issledovalsya s pomoshch'yu probojnikov i stal'nykh puansonov s bol'shoj skorost'yu shtampovki, obluchennykh v yadernom reaktore. Kruglye diski diametrom 10 mm shtampuyutsya iz stal'nogo lista s nizkim soderzhaniem ugleroda tolshchinoj 0,5 mm, nerzhaveyushchej stali i kremnievoj stali, sukhim sposobom i so smazkoj. Posle shtampovki izmeryalas' radioaktivnost' diskov otverstij. Kogda radioaktivnyj puanson zamenyalsya neradioaktivnym, to na diskakh obnaruzhivalas' neznachitel'naya radioaktivnost' v to vremya, kak radioaktivnost' v otverstiyakh edva izmenyalas'. EHto pokazalo, chto iznos puansona mozhno opredelit' po radioaktivnosti diskov, a iznos probojnikov - po radioaktivnosti otverstij. S pomoshch'yu ehtogo metoda iznos probojnikov i puansonov proveryalsya pri ispol'zovanii razlichnykh vidov smazochnogo materiala i metallicheskogo lista i byli polucheny sleduyushchie rezul'taty: 1) V nachale shtampovki skorost' iznosa kak probojnika, tak i puansona ochen' bol'shaya, no ona bystro snizhaetsya i stanovitsya, nakonets, postoyannoj posle

  1. Insight into the Local Solvent Environment of Biologically Relevant Iron-nitroysl Systems through Two-Dimensional Infrared Spectroscopy

    Science.gov (United States)

    Brookes, Jennifer Faith

    Iron-nitrosyl systems, particularly in the form of heme proteins, with their iron metal active sites play an important role in biological systems. Heme proteins act as storage, transporters, and receptors for nitric oxide (NO), a signaling molecule that is important in immune, nervous, and cardiovascular systems of mammals. By better understanding the local environment of the active site of NO binding heme proteins we can gain insight into disease in which the NO pathways have been implicated. This is an important step to being able to develop pharmaceuticals targeting NO pathways in humans. Sodium nitroprusside ((SNP, Na2[Fe(CN)5is NO]·2H 2O) investigated as a model system for the active site of nitric oxide binding heme proteins. Using two-dimensional infrared spectroscopy (2D IR) to obtain dephasing dynamics of the nitrosyl stretch (nuNO) in a series of solvents we are able to better understand the local environment of the more complicated metalloproteins. Rigorous line shape analysis is performed by using nonlinear response theory to simulate 2D IR spectra which are then fit to experimental data in an iterative process to extract frequency-frequency correlation functions (FFCFs). The time scales obtained are then correlated to empirical solvent polarity parameters. The analysis of the 2D IR lineshapes reveal that the spectral diffusion timescale of the nuNO in SNP varies from 0.8 -- 4 ps and is negatively correlated with the empirical solvent polarity scales. We continue to investigate NO binding of metalloproteins through 2D IR experiments on nitrophorin 4 (NP4). NP4 is a pH-sensitive NO transporter protein present in the salivary gland of the blood sucking insect Rhodius prolixus which undergoes a pH sensitive structural change between a closed and open conformation allowing for the storage and delivery of NO. The two structures are observed spectroscopically as two distinct pH-dependent nu NO frequencies at ~1904 and ~1917 cm-1. We obtain FFCFs by globally

  2. Aspectos entomológicos de la enfermedad de Chagas en Huallaga y Picota, San Martín, Perú

    Directory of Open Access Journals (Sweden)

    Abraham G. Cáceres

    2010-03-01

    Full Text Available Introducción: Existe escasa información y no actualizada sobre la presencia de triatominos en el departamento de San Martín, zona amazónica de nuestro país, y es importante actualizarla, ya que hay reportes recientes de casos de enfermedad de Chagas procedentes de la amazonía peruana cuyos vectores serían triatominos silvestres. Objetivos: Conocer la distribución geográfica de triatominos hematófagos en Huallaga y Picota, San Martín, Perú. Determinar los índices entomológicos, sus hábitos alimenticios y caracterizar los tripanosomatídeos que portan. Diseño: Investigación descriptiva observacional. Lugar: Red de Salud Huallaga y Picota, Laboratorio Regional de la Región de Salud San Martín. Laboratorios del Instituto Nacional de Salud. Participantes: Viviendas de 6 distritos de las provincia de Huallaga y 9 de Picota, del Departamento de San Martín. Intervenciones: La búsqueda de triatominos fue en 3 362 viviendas de áreas periurbanas y rurales. Mediante la prueba de precipitina, se determinó la fuente de alimentación. Se aisló tripanosomatídeos mediante infección en ratones Balb/C e inoculación en medio agar sangre, y por PCR se caracterizó el genoma por amplificación del espaciador intergénico del gen miniexón. Principales medidas de resultados: Determinar si Huallaga y Picota, San Martín, Perú, son zonas de riesgo de enfermedad de Chagas. Resultados: En 46 viviendas, de 3 362 muestreadas se capturó 53 triatominos adultos pertenecientes a Rhodnius pictipes (56,6%, Panstrongylus geniculatus (41,5% y Eratyrus mucronatus (1,9%. Se reporta P. geniculatus por primera vez para las dos provincias. Los índices de infestación para ambas provincias fueron 1,4% y 3,8%, respectivamente, y corresponden al índice de infección natural; mientras que el índice de dispersión fue 30,1%. En R. pictipes se identificó cinco fuentes de alimentación (pollo, humano, perro, cobayo y gato y en P. geniculatus un perfil

  3. Fauna Triatominae no Estado da Bahia, Brasil: as espécies e distribuição geográfica

    Directory of Open Access Journals (Sweden)

    Ítalo A. Shetlock

    1972-10-01

    Full Text Available Este é a primeira de uma série de publicações sobre os triatomíneos do Estado da Bahia, com base nos dados obtidos na inspeção de 889.972 domicílios de 11.045 localidades do Estado, nos anos de 1957 a 1971, quando se coletaram 33.588 exemplares do hemíptero. Foram identificadas 18 espécies pertencentes a 4 gêneros, conforme a seguir e relatado. Triatoma rubrovária, referida em antiga citação, não mais ocorre no Estado. Triatoma bahiensis perdeu sua validade específica, sendo considerada apenas urna variedade de T. pessoal. Existem também variedades de outras espécies, as quais serão estudadas com mais detalhes noutros trabalhes futuros. Panstrongylus megistus é principalmente abundante na faixa litorânea do Estado, com florestas latifoleadas, onde as condições de umidade são elevadas e oclima, é tropical quente e úmido. É a espécie considerada de maior importância na transmissão da Doença de Chagas na Bahia. T. brasiliensis foi encontrada comumente nas áreas de clima estépico com vegetação xerófila. A sua presença em áreas de clima, tropical quente e úmido, foi traduzida como sendo uma variedade da espécie. O seu encontro em áreas de florestas latifoleadas úmidas com clima de selvas, foi aceito como devido, possivelmente, ao transporte mecânico. Verificou-se que T. infestans, antes limitada ao paralelo 16° nos climas mesotérmicos está se disseminando, provavelmente por ação mecânica para áreas possuidoras de características climáticas diversas. T. sórdida foi encontrada somente nas áreas de clima seco seguindo de uma maneira geral o curso dos rios. T. rubrofasciata permaneceu com sua distribuição limitada a duas cidades coloniais na zona litorânea, rarefazendo-se nestes últimos anos, provavelmente devido a higienização por que passam os locais de sua antiga penetração. O gênero Rhodnius que é representado pelo R. negletus, constou de um só exemplar coletado num domicílio, em zona

  4. Hábitos alimentares, infecção natural e distribuição de triotomíneos domiciliados na região nordeste do Brasil Feeding habits, natural infection and distribution of domiciliary Triatominae bugs Northeast of Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1981-04-01

    Full Text Available São apresentadas as informações obtidas no inquérito triatomíneo levado a efeito na região nordeste do Brasil. As características biogeográficas incluem a presença de áreas semi-áridas da caatinga e amplas faixas transicionais com outras feições paisagísticas. Entre estas foram incluídas as da floresta tropical atlântica e as inclusões florestadas mais extensas. No período de 1975 a 1980 foram examinados 15.342 triotomíneos coletados no ambiente domiciliar, visando detectar as presenças de sangue ingerido e de infecção natural por Trypanosoma tipo cruzi. O conteúdo intestinal foi submetido a reações com antisoros para homem, cão, gato, roedor (Kattus, marsupial (Didelphis e ave (Gallus. Por ordem de freqüência, as espécies encontradas foram Triatoma pseudomaculada (40,6%, Panstrongylus megistus (19,7%, Triatoma brasiliensis e T. sordida (ambos com 14,3%, Rhodnius nasutus (6,1% e Triatoma infestans (1,1%; além de em algumas outras raras. A presença de sangue foi detectada em 42,4% e a infecção em 3,4% desse total de espécimens examinados. Observou-se elevada mobilidade alimentar, com coeficientes gerais de 54,8% para ave e 30,0% para homem. Em nível específico pôde determinar apreciável grau de antropofilia em P. megistus e, em menor intensidade, em T. brasiliensis. Por sua vez, T. infestans mostrou-se altamente antropófilo. Observou-se apreciável ornitofilia em T. pseudomaculata e T. sordida, com elevada intensidade em R. nasutus. Por outro lado, a presença de sangue humano em espécimens capturados no peridomicílio indicou a ocorrência de freqüente mobilidade espacial, com exceção de T. infestans que não mostrou evidências de abandonar o domicílio. A tendência à domiciliação, além desta, revelou-se apreciável em P. megistus, moderada em T. brasiliensi, T. pseudomaculata, T. sordida e praticamente nula em R. nasutus. A distribuição geográfica confirmou o caráter autóctone de T

  5. ECOFERM. The closed-cycle farm; ECOFERM. De kringloopboerderij

    Energy Technology Data Exchange (ETDEWEB)

    Van Liere, J. [Van Liere Management, Utrecht (Netherlands); Boosten, G. [Stichting DOTank, Bussum (Netherlands); Van Dijk, L. [Sustec Consulting Contracting, Wageningen (Netherlands); Hemke, G. [Hemke Nutriconsult, Best (Netherlands); Verschoor, A. [Ingrepro, Borculo (Netherlands); Van Kasteren, J. (ed.)

    2011-06-15

    , ammoniak, waterdamp, CO2 en restwarmte) worden gebruikt voor de productie van algen, biogas, elektriciteit en schoon water. Het begint met het dagelijks en gescheiden afvoeren van de mest uit de stal. Hierdoor komen minder ammoniak en andere schadelijke stoffen vrij, met een veel aangenamer stalklimaat voor de dieren en de boer als gevolg. De door de dieren geproduceerde CO2 , waterdamp en lichaamswarmte worden samen met de ammoniak in de stallucht door een reactor gevoerd en benut voor de algenkweek. De afgevoerde, deels ontwaterde mest gaat naar een centrale vergister voor de productie van biogas en elektriciteit in een WKK. De dunne mestfractie en het verder geraffineerde digestaat leveren de mineralen (vooral stikstof en fosfor) voor de algenkweek. De voorkweek van de algen vindt plaats in een gesloten bioreactor; de verdere uitgroei in een open vijver (hybride teelt). De algen dienen als gedeeltelijke vervanging van sojaschroot en visolie in het voer, maar kunnen ook worden gebruikt als bron voor medicijnen of voedingssupplementen. De gezondheidsbevorderende stoffen (zoals de omega-3-vetzuren) in de algen en het gezondere stalklimaat verbeteren de algehele conditie en het welzijn van de dieren. Daardoor zijn minder antibiotica nodig. Het concept ECOFERM betekent op essentiële punten een breuk met de huidige varkenshouderij. Het leidt tot een beter welzijn en gezondheid van de dieren, en tot vermindering van antibioticagebruik, tot vervanging van soja en visolie en tot het tegengaan van schadelijke emissies door het sluiten van kringlopen.

  6. Dėl keleto retų vietovardžių kilmės (Greikónys, Grìkapėdis, Plasapnỹkai, Pušė́nai, Silgiónys, Tauliùkai, Vaĩsodžiai

    Directory of Open Access Journals (Sweden)

    Jonas Palionis

    2011-12-01

    augenscheinlich auf eine anthroponymische Herkunft aus dem Familiennamen Puišỹs hin, wobei man diesen auf das Adjektiv puĩšis, puĩšas ‘schmutzig’ zurückführen kann.Silgiónys, die ältere Form Stilgionys (de Stylgiany ist in den genannten Quellen des 17.–18. Jhs bezeugt. Die gegenwärtige Form (ohne t tauchte, sofern man heute schließen kann, Ende des 17. Jhs auf und verbreitete sich im 18. Jh. Ungeachtet dessen, daß solch ein Familienname wie Stilgionis (resp. Silgionis bislang nicht bezeugt ist, kann kein Zweifel bestehen, daß der entsprechende Ortsname auf dieser Grundlage entstanden ist. Den anthroponymischen Ursprung läßt u. a. der existierende Familienname Stalgỹs voraussetzen. Die mögliche Variante von Stalgỹs konnte noch *Stilgỹs sein, diese wurde mit den Verben stìlgti, stal̃gti ‘neugierig sein’ in Verbindung gesetzt. Man kann also annehmen, daß der Familienname aufgrund des Beinames, der die Bedeutung ‘der neugierige Mensch’ hatte, entstanden sein konnte.Tauliùkai ist zweifellos auch anthroponymischen Ursprungs, denn dieser Ortsname hat eine genaue Entsprechung in dem Familienname Tauliùkas (Tauluk, der bereits 1658 in den Tauf- und Trauungsurkunden fixiert ist. Die Enstehung dieses Familiennamens läßt auch keine Zweifel zu: er ist von dem Adjektiv taulùs ‘fern’ abgeleitet. Die Basis von Tauliùkas vermutlich *Taulius oder *Taulas (vgl. Taulãvičius.Vaĩsodžiai hatte, wie es aus den ältesten genannten Quellen ersichtlich ist, den Bindevokal [a] und wurde in der Singularform gebraucht (Vaitasodis: de Weytasodzia. Aber die Pluralformen kommen bereits in der zweiten Hälfte des 17. Jhs parallel vor (de Waytasady, Waytasadzi. Aus den Komponenten dieser Zusammensetzung (vaĩtas ‘Vogt’ + sõdžius ‘Dorf’ wird klar, das Vaĩsodžiai nicht als anthroponymischer Ortsname aufzufassen ist und das er im Laufe der Entwicklung manchen phonetischen Änderungen unterzogen Worden ist.

  7. Use of radioisotopes in the systematic analysis of impurities in metals of very high purity; Application des radioisotopes a l'analyse systematique des impuretes dans les metaux de tres haute purete; Primenenie radioizotopov v sistematicheskom analize primesej v vysokochistykh metallakh; Aplicacion de los radioelementos al analisis sistematico de las impurezas en los metales muy puros

    Energy Technology Data Exchange (ETDEWEB)

    Albert, Philippe; Gaittet, Jean [Centre d' Etudes de Chimie Metallurgique (C.N.R.S.), Vitry (France)

    1962-01-15

    insistiran especialmente en los resultados y en las consecuencias de los analisis por ellos realizados. (author) [Russian] tsentratsiya primesej dostigaet poryadka 10{sup -6} - 10{sup -8}. EHti metally izgotovlyayutsya v nebol'shikh kolichestvakh, i ochen' vazhno umet' tochno opredelyat' kolichestvennym analizom ochen' bol'shoe chislo ehlementov v odnoj probe. Sistematicheskij analiz alyuminiya i zheleza pri pomoshchi nejtronnogo oblucheniya pozvolil nam proizvesti kolichestvennyj analiz 45 ehlementov v odnoj probe poryadka odnogo gramma. EHtot analiz bol'shogo chisla primesej stal vozmozhnym lish' blagodarya kaskadnomu razdeleniyu poluchivshikhsya vo vremya oblucheniya radioizotopov na bolee chem 40 analiticheskikh fraktsij. Zatem bol'shinstvo radioizotopov izoliruetsya v chistom vide radiokhimicheskim putem, a ikh identifikatsiya dostigaetsya putem odnovremennogo izucheniya perioda ikh radioaktivnogo raspada i spektra ikh gamma-izlucheniya. Odnako, dopolnyaya ehtot sistematicheskij analiz k olichestvennym analizom nekotorykh ehlementov v otdel'noj probe, mozhno opredelyat' a Ktivatsionnym metodom okolo 60 ehlementov, libo obluchaya ikh nejtronami (sera, fosfor, khlor, barij...), libo pri pomoshchi reaktsij, vyzvannykh nejtronami (uglerod i bor). V nashem doklade my namereny osobo ostanovit'sya na rezul'tatakh i posledstviyakh nashikh analizov. (author)

  8. Measurement of the wear rate of cast grinding balls using radioactive tracers; Evaluation de l'usure des boulets pour concasseurs, au moyen des indicateurs radioactifs; Izmerenie skorosti iznosa litykh drobil'nykh sharov pri pomoshchi mechenykh atomov; Medicion de la velocidad de desgaste de bolas trituradoras de acero colado con ayuda de indicadores radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Keys, J D; Eichholz, G G [Department of Mines and Technical Surveys, Ottawa, ON (Canada)

    1962-01-15

    'nykh sharov v razlichnykh rabochikh usloviyakh i dlya sopostavleniya rezul'tatov, poluchaemykh s sharami raznykh tipov ili raznogo sostava, byli uspeshno ispol'zovany mechenye atomy. Na protyazhenii neskol'kikh nedel' bylo provedeno nablyudenie za partiej mechenykh stal'nykh sharov v drobil'noj rabote i byli sobrany statisticheskie dannye otnositel'no iznosa i poteri vesa. V khode opytnykh tsiklov do otlivki sharov k rasplavlennomu metallu byl dobavlen kobal't-60 i posle ehtogo bylo provedeno nablyudenie nad litymi sharami v ikh rabote na razrabotkakh zheleznoj rudy. Partiya mechenykh radioizotopami sharov byla dobavlena k drobil'nym sharam drobilki s normal'noj emkost'yu zagruzki priblizitel'no v 75 tonn, H cherez kazhduyu nedelyu iz drobilki vybiralis' obraztsy zagruzki dlya iz{sup y}atiya mechenykh sharov. EHti shary proveryalis' i vzveshivalis' i podschityvalas' skorost' ikh iznosa. EHtot metod okazalsya praktichnym sposobom issledovaniya svojstv iznosa v rabochikh usloviyakh na ustanovke. (author)

  9. Fission gas pressure build-up and fast-breeder economy; Accumulation de la pression des gaz de fission et economie des reacteurs surgenerateurs a neutrons rapides; Nakoplenie davleniya gazov produktov deleniya i ehkonomika reaktorov-razmnozhitelej na bystrykh nejtronakh; Aumento de la presion de los gases de fision y economia de los reactores reproductores rapidos

    Energy Technology Data Exchange (ETDEWEB)

    Engelmann, P [Kernforschungszentrum, Karlsruhe (Germany)

    1962-03-15

    materiales de alta resistencia, tales como el Inconel-X y el molibdeno pueden soportar la presion de los gases de fision a las temperaturas de funcionamiento corrientes. Desgraciadamente , la seccion eficaz de absorcion de estos materiales es superior a la del acero inoxidable. El autor presenta los resultados de calculos, realizados segun una teoria de varios grupos, que permite conocer el efecto de la utilizacion de estos materiales y de la disminucion de la densidad del combustible, sobre la masa critica y sobre la razon de reproduccion en los reactores reproductores de pequenas y medianas dimensiones. (author) [Russian] Na stoimost' toplivnogo tsikla i na vremya udvoeniya reaktorovbriderov na bystrykh nejtronakh sil'no vliyaet stepen' dostigaemogo vygoraniya topliva. Ispol'zovani e oksidnogo ili karbidnogo topliva daet vozmozhnost' dostignut' vygoraniya poryadka 100 000 mvt-n/t. V toplivnykh ehlementakh s pokrytiem ogranichivayushchi m faktorom yavlyaetsya rost gazov produktov deleniya. Pri rassmatrivaemo m vysokom vygoranii poddayushchayasya otsenke fraktsiya gazov, obrazuemykh pri delenii, popadaet v pory i tem samym uvelichivaet davlenie na obolochku. Iskhodya iz izvestnykh vykhodov produktov deleniya i tsepochek raspada bylo vychisleno kolichestvo obrazuyushchegosya gaza i sozdavaemoe im davlenie. Pri raschete davleniya, dejstvuyushchego na obolochku, byli ispol'zovany tri fizicheskikh modeli: i) gaz soderzhalsya v svyazanykh mezhdu soboj porakh, ii) v otdel'nykh porakh i iii) v tsentral'nom otverstii. Budet rassmotrena zavisimost' davleniya ot svobodnogo ob{sup e}ma (plotnost' topliva) i temperatury. Obolochki, izgotovlennye iz vysokoprochnykh materialov, naprimer, iz inkonelya-Kh i molibdena, mogli by vyderzhat' pri rabochikh temperaturakh davlenie gazov, vydelyayushchikhsya v rezul'tate deleniya. K sozhaleniyu, ehti materialy obladayut bolee vysokimi poperechnymi secheniyami pogloshcheniya, chem nerzhaveyushchaya stal'. Budut dany rezul'taty mnogogruppovog o

  10. Olympijské hry jako kulturní událost The Olympic Games as a cultural event

    Directory of Open Access Journals (Sweden)

    Zvezdan Savić

    2007-02-01

    Full Text Available Olympijské hry se staly událostí zahrnující mnoho sportů, která zaměstnává nejen sportovce z různých zemí, ale také milióny diváků z celého světa. Z hlediska veřejného zájmu tedy převyšují jakoukoliv jinou sportovní nebo kulturní událost. Z iniciativy několika málo zemí a malého počtu sportovců se vyvinul historický fenomén dnešní civilizace, odehrávající se na určeném místě, s vlastními soutěžícími, nabídkou a pravidly. Olympijské hry vyjadřují ideologii různých národů na jediném místě, ideologii náboženství, zvyků, tradic, jazyků nebo obecně kultur. Probíhá při nich masová komunikace mezi soutěžícími a zbytkem celého světa. Sociální, vědecký, sportovně-technický a politický vývoj otevřel sportu jako sociálně-kulturnímu jevu široké obzory a sport se stal obecně prospěšným. Olympijských her se dnes účastní více než sto devadesát zemí. Sportovci a rozhodčí pocházejí z různých sociálních prostředí, což bylo v době, ve které hry vznikly, něco nepředstavitelného. Přesto je sociální komunikace mezi mladými lidmi celého světa v rámci této grandiózní události významným prvkem dnešních olympijských her. Můžeme při nich sledovat mistrovské sportovní výkony i setkávání mladých lidí bez ohledu na ideologii, rasu a náboženství. Právě to činí hry mimořádně krásnými a významnými. Autoři výzkumu se snažili podat podrobnější vysvětlení důležitých kulturních aspektů olympijských her a ukázat jejich sociální kontext. The Olympic Games have become a multi sport event, which entertains not only athletes from different countries, but a world wide audience numbering millions. They therefore exceed any other sports or cultural event when it comes to matters of public interest. Deriving from the initiative of a few countries and a small number of athletes, a historically significant phenomenon

  11. The effective lifetime and temperature coefficient in a coupled fast-thermal reactor; Temps de vie effectif et coefficient de temperature dans un reacteur a couplage neutrons rapides-neutrons thermiques; Ehffektivnyj srok zhizni i temperaturnyj koehffitsient nejtronov v dvoyakom reaktore na bystrykh i teplovykh nejtronakh; Vida efectiva y coeficiente de temperatura en un reactor con acoplamiento rapido-termico

    Energy Technology Data Exchange (ETDEWEB)

    Haefele, W. [Kernforschungszentrum, Karlsruhe (Germany)

    1962-03-15

    . Teplovoj komponent dejstvuet kak svoego roda zamedlitel' vremeni zhizni nejtronov. Kak i v teorii zapazdyvayushchikh nejtronov, ehffekt zapazdyvaniya ischezaet, esli reaktivnost' dostatochno vysoka, chtoby bystryj komponent stal kritichnym sam po sebe. V issledovanii rassmatrivalsya sparennyj reaktor, v kotorom bystryj komponent podvergaetsya dejstviyu vnezapnogo stupenchatogo skachka reaktivnosti {alpha}{sub 0}. Izza vozrastayushchego urovnya ehnergii temperatura podnimaetsya i nachinayut rabotat' dva temperaturnykh koehffitsienta: temperaturnyj koehffitsient bystrogo komponenta i temperaturnyj koehffitsient teplovogo komponenta. Ehta problema rassmatrivaetsya s odnoj gruppoj zapazdyvayushchikh nejtronov (v obychnom znachenii). Privoditsya formalizm dlya vyrazheniya ehffektivnogo sroka zhizni i temperaturnogo koehffitsienta vo vremya razlichnykh stadij issledovaniya. Dany takie otkloneniya dlya razlichnykh znachenij {alpha}{sub 0}, pri kotorykh dostigaetsya predel kinetiki reaktorov na bystrykh nejtronakh. (author)

  12. Profesionalismus a amatérismus v zrcadle socialistického sportu [Professionalism and amateurism in the mirror of the socialistic sport

    Directory of Open Access Journals (Sweden)

    Brigita Stloukalová

    2008-02-01

    Full Text Available Po 2. světové válce se sport ocitl v nových společenských poměrech, určených existencí dvou světových hospodářských soustav. Dlouholetý předseda Mezinárodního olympijského výboru (dále MOV Avery Brundage odolal tlaku mezinárodních sportovních federací i národních olympijských výborů na vyplácení tréninkových a cestovních nákladů, jeho následovník lord Michael Killanin už uzdu povolil. Stavidla s definitivní platností otevřel ambiciózní Juan Antonio Samaranch, který se stal neomezeným diktátorem olympijského hnutí v 80. a 90. letech 20. století. Právě on umožnil vyplácení vysokých finančních částek sportovcům, a tím i účast profesionálních sportovců na olympijských hrách. Jaký vlastně byl vztah tzv. amatérského a profesionálního sportu? Byli sportovci v socialistických zemích amatéři nebo profesionálové? Jak socialistické země akceptovaly změny v olympijském hnutí v osmdesátých letech minulého století? Na tyto otázky se snaží předložený text odpovědět, přičemž hlavním zdrojem informací jsou soudobé dokumenty a denní tisk. [Professional and amateur sport formed as picture of society lay-out in modern history. The first amateur definitions considered as the professional everybody who had exercised manual labour. VIII. Olympic Congress in Prague in 1925 established the professional practised a sport for money or received a refund of wages. This definition had survived in almost unchanged form as late as the second half of the 20th century, when sport stepped foot inside new social conditions determined with two world economic systems existence. The VIII. Olympic congress in Prague in 1925 established nobody could participate in the Olympic Games: 1 who was professional or had been professional wittingly in his sport or other one, 2 who received refund of wages. This definition in unchanged form had lived through by the second half of the 20th

  13. Autoradiography of Sectioned Soil Cores; Autoradiographie de Carottes de Sol; Radioavtografiya otrezkov prob pochvy; Autorradiografia de Cortes de Testigos de Suelo

    Energy Technology Data Exchange (ETDEWEB)

    Held, E. E.; Gessel, S. P.; Matson, L. J.; Billings, R. F. [University of Washington, Seattle (United States)

    1965-10-15

    de grano extrafino. Con placas nucleares o con cubreobjetos previamente sumergidos en emulsion nuclear se puede efectuar un examen microscopico y distinguir entre emisores alfa y beta. Por estos metodos se han localizado en suelos de las islas Marshall radionuclidos emisores alfa, beta y gamma procedentes de precipitaciones radiactivas. Las partes radiactivas de los testigos se pueden separar y analizar por espectroscopia gamma o analisis radioquimicos, determinando asi translocaciones selectivas y la adsorcion de ciertos radionuclidos en el sistema suelo-raices. Los principales radionuclidos estudiados en suelos por esta tecnica comprenden el {sup 54}Mn, {sup 60}Co, {sup 90}Sb, {sup 125} Sb, {sup 1}'3{sup 7}Cs, {sup 144}Ce, {sup 155}Eu, {sup 239}Pu. (author) [Russian] Opisyvajutsja metody opredelenija otdel'nyh radioizotopov, svjazannyh s opredelennymi komponentami pochvy i kornjami rastenij v probah pochv. Pri pomoshhi stal'nyh trub iz pochvy v polevyh uslovijah brali proby diametrom do 10 sm i dlinoju 30 sm. Vysushennye v pechi proby zapolnjali plasticheskoj massoj; za iskljucheniem periferii, nikakih vidimyh narushenij pochvy na protjazhenii vsej proby ne nabljudalos'. Proby raspilivali pri pomoshhi almaznoj pily na seriju otrezkov, poverhnost' kotoryh poluchaetsja dostatochno gladkoj dlja radioavtografii. Dlja radioavtogramm so slabym razresheniem ispol'zovali bezjekrannuju rentgenovskuju plenku s otnositel'no korotkim vremenem vyderzhki. Pri nalichii dostatochnoj radioaktivnosti mozhno poluchat' bolee tochnye rezul'taty na osoboj melkozernistoj rentgenovskoj plenke, no dlja jetogo trebuetsja bol'shaja vyderzhka. Plastinki dlja proslezhivanija jadernyh sledov ili pogruzhennye v jemul'siju, soderzhashhuju sledy jader, zashhitnye stekla delajut vozmozhnym mikroskopicheskoe issledovanie i pozvoljajut obnaruzhivat' razlichie mezhdu al'fa- i beta-izluchateljami. Jeti metody pozvolili lokalizirovat' al'fa-, beta- i gamma-izluchajushhie izotopy radioaktivnyh osadkov

  14. Area-wide control of Chagas disease vectors in Latin America

    International Nuclear Information System (INIS)

    Schofield, C.J.

    2000-01-01

    transmission by the year 2000 (WHO 1997b). Programme costs were originally estimated at US$190-350 million over the 10-year period, with most of the investment to be committed during the initial attack phase over the first 3 years. In fact, investment to date has been just over US200 million and recent studies in Brazil and Argentina have revealed economic rates of return in excess of 30% and 60%, respectively (Akhavan 1996, Basombrio et al. 1998). With successful control or elimination of T. infestans and R. prolixus and control of sympatric vectors, a figure approaching 70% of Chagas disease transmission will be interrupted, while large-scale improvements in blood bank screening will interrupt a further 10-15%. But maintenance of this success and further progress, will depend very largely on improved systems of entomological surveillance and these in turn will depend crucially on maintaining political continuity for the control and surveillance programmes. Although technologically simple, the administrative scale of the regional Chagas disease control initiatives has revealed major complexities and intervention coverage has not been entirely uniform. In each country the programmes have faced difficulties primarily of an administrative nature, especially as each country has simultaneously sought to decentralise its intervention services - producing inevitable disruption to the chain of operational decisions and lapses in entomological surveillance. Already there are indications of little-known species of Triatominae adapting to new domestic habitats and our understanding of this evolutionary process is still in its infancy. It should not be forgotten - especially by those responsible for budgetary priorities - that the domestication of Triatominae and initiation of Chagas disease transmission is a relatively recent phenomenon. Experience shows that we can now combat this, but if we relax vigilance, it could happen again

  15. Fixation of Simulated Highly Radioactive Wastes in Glassy Solids; Fixation de Dechets Simules de Haute Activite dans des Soudes Vitreux; 0424 0418 041a 0421 0410 0426 0418 042f 0418 041c 0418 0422 0418 0420 041e 0412 0410 041d 041d 042b 0425 0420 0410 0414 0418 041e 0410 041a 0422 0418 0412 041d 042b 0425 041e 0422 0425 041e 0414 041e 0412 0412 042b 0421 041e 041a 041e 0419 0410 041a 0422 0418 0412 041d 041e 0421 0422 0418 0421 0422 0415 041a 041b 041e 041e 0411 0420 0410 0417 041d 042b 041c 0418 0422 0412 0415 0420 0414 042b 041c 0418 0412 0415 0429 0415 0421 0422 0412 0410 041c 0418 ; Fijacion de Desechos Simulados de Elevada Radiactividad en Solidos Vitreos

    Energy Technology Data Exchange (ETDEWEB)

    Clark, W. E.; Godbee, H. W. [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1963-02-15

    -processa'' (aljuminij, HNO{sub 3}) i ''Dareks-processa'' (nerzhavejushhaja stal', HNOa) pokazali tehnologicheskuju vypolnimost' takogo processa. Plotnye mikrokristallicheskie tverdye veshhestva mogut byt' stol' zhe priemlemymi, kak istinnye stekla; ih bol'shaja teploprovodnost' v nekotoroj mere vozmeshhaet uvelichenie poverhnosti po sravneniju s istinnymi steklami. V laboratorii byli izgotovleny fosfatnye i borfosfatnye stekla iz othodov vseh jetih treh vidov. Letuchest' cezija byla ogranichena do -v0,1% za schet fizicheskogo uvlechenija, a letuchest' rutenija byla snizhena do <0,3% dobavleniem fosfita i gipofosfita. Drugimi dobavochnymi veshhestvami sluzhili: PbO, Ca (OH){sub 2}, NaOH i MgO. Udel'nyj ves massy izmenjalsja ot 2,36 do 2,90 g/cm{sup 3} dlja othodov 'TBF-25-processa' i ot 2,63 do 2,60 g/smje dlja othodov {sup P}ureks-processa{sup .} Ob{sup e}m umenyvaloja po sravneniju s ishodnymi ob{sup e}mami koncentrirovannyh rastvorov othodov v pervom sluchae v 7,2 - 9,3 raza i vo vtorom sluchae v 5,7 - 8,3 raza; tochki nachal'nogo razmjagchenija izmenjalis' sootvetstvenno ot 675 do 1 000 Degree-Sign C i ot 830 do 975vS. Rezul'taty opytov o othodami 'Dareks-processa' vse eshhe nosjat predvaritel'nyj harakter. V rezul'tate polunepreryvnogo processa v poluproizvodstvennom masshtabe poluchalis' istinnye stekla iz othodov ''TBF-25-processa'' i mikrokristallicheskoe tverdoe veshhestvo iz othodov {sup P}ureks- processa{sup .} Teploprovodnost' stekla izmenjalas' ot 1,05 britanskih termicheskih edinic v chas na fu*g i na 1 Degree-Sign F pri 320 Degree-Sign F do 1,6 pri 1 050 Degree-Sign F, t.e. ona v 10 raz prevyshala teploprovodnost' obzhigaemogo veshhestva bez dobavok. Blagodarja dobavleniju fosfita letuchest' rutenija snizhalas' do <10%. Nerzhavejushhaja stal' javljaetsja udovletvoritel'nym materialom dlja izgotovlenija kontejnerov dlja obzhiganija i fiksacii. Pochti vsja vnutrennjaja korrozija proishodit v techenie otnositel'no korotkogo perioda vremeni (2-6 chasov), v techenie kotorogo

  16. Automatic Sample Changing System for Gamma-Ray Spectrometry; Changeur Automatique d'Echantillons Pourla Spectrometrie Gamma; Avtomaticheskaya sistema dlya smeny obraztsov pri gamma-spektrometrii; Cambiador Automatico de Muestras para Espectroscopia Gamma

    Energy Technology Data Exchange (ETDEWEB)

    Lamson, K. C.; Sesko, W. J.; Nicholson, G. C. [Northeastern Radiological Health Laboratory, Winchester, MA (United States)

    1965-10-15

    ha solicitado una patente, viene funcionando satisfactoriamente desde hace mas de un ano en el Northeastern Radiological Health Laboratory. Su costo total, inclusive la mano de obra, fue inferior a 2000 dolares. (author) [Russian] Obnaruzhenie prirodnyh kolichestv gamma-izluchajushhih radioizotopov v biologicheskoj srede trebuet vysokoj chuvstvitel'nosti schetnoj sistemy. Dlja togo, chtoby poluchit' dostatochno tochnye dannye, trebuetsja mnogo vremeni, ot odnogo do neskol'kih chasov. Naibolee jeffektivnoe ispol'zovanie dorogostojashhego gamma-spektrometricheskogo schetnogo oborudovanija s nizkim fonom trebuet ego nepreryvnoj raboty. Dlja jetogo neobhodimo libo postojannoe prisutstvie personala, libo nalichie polnost'ju avtomatizirovannoj sistemy, vkljuchajushhej smenu obrazcov i registraciju dannyh. Cel'ju nastojashhego doklada javljaetsja opisanie avtomatizirovannoj gamma-spektrometricheskoj schetnoj sistemy, sproektirovannoj, izgotovlennoj i rabotajushhej v radiologicheskoj laboratorii v Uinchestere, shtat Massachusets. Prisposoblenie dlja smeny obrazcov bylo sproektirovano dlja raboty v sochetanii s bol'shim stal'nym jekranirovannym kontejnerom, i dlja jetoj celi mozhno legko primenit' ljuboe imejushheesja v prodazhe prisposoblenie takogo roda s otkryvajushhejsja perednej dvercej. Prisposoblenie oborudovano takim obrazom, chtoby obrabatyvat' razlichnye obrazcy, v tom chisle biologicheskie i medicinskie. Ono sostoit iz vrashhajushhegosja lotka, rasschitannogo na shestnadcat' obrazcov, sistemy periodicheskoj krugovoj podachi dlja ustanovki obrazcov v nuzhnoe polozhenie, mehanicheskoj ruki s jelektromagnitom dlja vvedenija i vyemki obrazcov iz kontejnera i rychaga dlja otkryvanija i zakryvanija dvercy kontejnera. Sistema dlja smeny obrazcov soedinena s mnogokanal'nym analizatorom, kotoryj obespechivaet bezopasnost', preryvaja cikl v sluchae neispravnosti v ljuboj faze. Posle zadannogo vremeni scheta dannye nanosjatsja putem punshirovanija na bumazhnuju lentu i

  17. The Origin and Nature of Radioactive Wastes in the United States Atomic Energy Programme; Origine et Nature des Dechets Radioactifs de l'Execution des Programmes d'Energie Atomique aux Etats-Unis; 041f 0420 041e 0418 0421 0425 041e 0416 0414 ; Origen y Naturaleza de los Desechos Radiactivos en el Programa de Energia Atomica de los Estados Unidos

    Energy Technology Data Exchange (ETDEWEB)

    Bruce, F. R. [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1960-07-01

    clases de desechos: desechos de actividad media, que resultan de la disolucion quimica, y contienen el 0,1 per ciento, aproximadamente, del total de los productos de fision, y desechos de actividad elevada, que contienen el resto de los productos de fision en una solucion diluida de acido nitrico. El volumen de los desechos evaporados varia entre 0,8 1 per kilogramo de uranio, para los combustibles poco enriquecidos y 500 1 por kilogramo de uranio, para los muy enriquecidos, se prove que la industria nuecleoelectrica de los Estados Unidos producira como termino medio unos 5 1 de desechos de actividad elevada y media por kilogramo de uranio utilizado. En los Estados Unidos se calcula que para 1970 esta industria habra producido unos 3 x 10{sup 9} curies disueltos en un volumen de 2,7 x 10{sup 7} l y 6 x 10{sup 10} curies en 1,1 x 10{sup 9} l de solucion para el ano 2000. Los desechos procedentes de los reactores generadores plantean, por razon de su composicion, nuevos problemas de almacenamiento y evacuacion. (author) [Russian] Sostav othodov, obrazuemyh pri jekspluatacii reaktorov, zavisit, vo-pervyh, ot obrabotki, kotoraja primenjaetsja pri vosproizvodstve toplivnyh jelementov, i, vo-vtoryh, ot pervonachal'nogo sostava toplivnyh jelementov. Pri obrabotki s primeneniem jekstrakcii vodnyh rastvorov vysokaja, srednjaja i nizkaja aktivnost' othodov voznikaet v priblizitel'nom ob'emnom sootnoshenii, ravnom odnomu, pjati i 100 sootvetstvenno. Othody, voznikajushhie v rezul'tate vosproizvodstva vysokoobogashhennyh toplivnyh jelementov, byvajut bol'shimi po ob{sup e}mu, tak kak oni soderzhat toplivnyj razbavitel'. Nizkoobogashhennye toplivnye jelementy obychno sostojat iz uranovoj serdceviny, pokrytoj aljuminiem, cirkoniem ili nerzhavejushhej stal'ju ; jeti jelementy dajut dva vida othodov. Pervye othody srednej stepeni aktivnosti, soderzhashhie okolo 0,1% produktov raspada, voznikajut v rezul'tate himicheskogo rastvorenija. Vtoroj vid othodov s vysokoj stepen'ju aktivnosti

  18. Design, Fabrication and Performance of Boron-Carbide Control Elements; Conception, Fabrication et Comportement de Lames de Commande en Carbure de Bore; Raschety, izgotovlenie i kharakteristiki reguliruyushchikh sterzhnej. Iz karbida Bora; Proyecto, Elaboracion y Rendimiento de Elementos de Control de Carburo de Boro

    Energy Technology Data Exchange (ETDEWEB)

    Brammer, H. A.; Jacobson, J. [General Electric Company, San Jose, CA (United States)

    1964-06-15

    acero al boro y motivos por los que se abandonaron en favor del carburo de boro. 2. Desarrollo progresivo del elemento de carburo de boro, comenzando con los primeros experimentos y las mediciones iniciales llevadas a cabo en el Vallecitos Atomic Laboratory en el marco del programa de desarrollo de materiales para barras de control de la AEC, hasta llegar a una descripcion de la configuracion definitiva de la barra de control. 3. Elaboracion de los elementos y procedimientos de control de calidad. 4. Resultados de los ensayos para determinar las caracteristicas mecanicas y la reactividad. 5. Experiencia adquirida Con los elementos y datos sobre los resultados de la inspeccion mecanica y de los ensayos de la reactividad al cabo de 2 aflos de utilizacion en los reactores. (author) [Russian] Regulirujushhee ustrojstvo s ispol'zovaniem krestoobraznoj kasety, Sostojashhej iz trubok iz nerzhavejushhej stali, zapolnennyh karbidom bora (B{sub 4}C), stali primenjat' v re aktorah s kipjashhej vodoj v aprele 1961 goda. S jetogo vremeni kasety stali standartnym jetalonom upravljajushhih sterzhnej v reaktorah s kipjashhej vodoj kompanii {sup D}zhene- ral Jelektrik{sup .} Oni zamenili kasety iz nerzhavejushhej stali s 2%-nym soderzhaniem bo r a . Jeti krestoobraznye kasety sostojat iz nabora nebol'shih vertikal'nyh trub iz nerzhavejushhej stali, zapolnennyh plotnym poroshkom karbida bora. Poroshok karbida bora pomeshhen v prodol'nom napravlenii v nezavisimyh otdalenijah putem gorjachej pakovki nad sharikopodshipnikami, razmeshhennymi, razmeshhennymi vnutri trub. R azr abotka i ispol'zovanie regulirujushhih sterzhnej iz karbida bora obsuzhdaetsja po sledujushhim pjati fazam: 1. Kratkoe opisanie opyta s pomoshh'ju stal'nyh kaset, soderzhashhih bor, i prichiny perehoda k regulirujushhim sterzhnjam iz karbida bora. 2 . Ustrojstvo kaset iz karbida bora, nachinaja s jeksperimentov po ra zrab otke i vkljuchaja samye pervye meroprijatija, provedennye v KAJe po ''Materialam dlja

  19. Treatment, Processing and Future Disposal of Radioactive Wastes at the Idaho Chemical Processing Plant; Traitement et Elimination Future des Dechets Radioactifs a l'Usine de Traitement Chimique de L'Idaho; 0410 041d 0414 ; Tratamiento y Evacuacion de Desechos Radiactivos en la Planta de Tratamiento Quimico de Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, James I. [Phillips Petroleum Company, Atomic Energy Division, Idaho Falls (United States)

    1960-07-01

    tratamiento supone pueden a veces quedar compensados por la reduccion de los gastos por concepto de almacenamiento. La baja conductividad termica de los solidos obliga a conceder mayor importancia a la temperatura de almacenamiento que en el caso de los liquidos. Los desechos acidos de nitrato aluminico que se forman al tratar los combustibles del tipo utilizado en los reactores de ensayo de materiales (MTR), pueden transformarse en alumina granular por calcinacion en un lecho fluidificado, a una temperatura comprendida entre 350 Degree-Sign y 550 Degree-Sign C. Los principales componentes de tal instalacion son: el calcinador alentado por una aleacion de NaK, un sistema.de depuracion de los gases desprendidos y los tanques para el almacenamiento de solidos. El autor describe el diseno de la instalacion, asi como el programa de investigaciones y desarrollo. Basandose en los resultados favorables obtenidos con este sistema de calcinacion en lecho fluidificado y almacenamiento de solidos a elevada temperatura, y en otras consideraciones, el autor examina diversos sistemas de almacenamiento y sus relaciones con el medio ambiente. (author) [Russian] Kislotnye othody, poluchajushhiesja ot rekuperacii obogashhennogo urana iz toplivnyh jelementov s aljuminiem, cirkoniem i nerzhavejushhej stal'ju na Zavode po himicheskoj pererabotke v Ajdaho, hranjatsja v podzemnyh bakah dvuh razlichnyh geometricheskih form s nominal'noj emkost'ju v 30,000 i 300,000 gallonov. V dokumente opisyvajutsja konstrukcii i rabo ta ustanovki dlja hranenija othodov v bakah, a takzhe metody udalenija v okruzhajushhuju sredu othodov s nizkim urovnem aktivnosti. Princip ''koncentracii i uderzhanija'' pri udalenii othodov vylilsja v konechnuju formu proizvodstva tverdoj massy, soderzhashhej produkty delenija. Nevygoda ot uvelichenija stoimosti obrabotki mozhet byt' pokryta sokrashheniem stoimosti hranenija, no ne vo vseh sluchajah. Vvidu nizkoj teploprovodnosti tverdyh tel soobrazhenija o temperature hranenija

  20. FOREWORD: Tackling inverse problems in a Banach space environment: from theory to applications Tackling inverse problems in a Banach space environment: from theory to applications

    Science.gov (United States)

    Schuster, Thomas; Hofmann, Bernd; Kaltenbacher, Barbara

    2012-10-01

    iterative method. A powerful tool for proving convergence rates of Tikhonov type but also other regularization methods in Banach spaces are assumptions of the type of variational inequalities that combine conditions on solution smoothness (i.e., source conditions in the Hilbert space case) and nonlinearity of the forward operator. In Parameter choice in Banach space regularization under variational inequalities, Bernd Hofmann and Peter Mathé provide results with general error measures and especially study the question of regularization parameter choice. Daijun Jiang, Hui Feng, and Jun Zou consider an application of Banach space ideas in the context of an application problem in their paper Convergence rates of Tikhonov regularizations for parameter identifiation in a parabolic-elliptic system, namely the identification of a distributed diffusion coefficient in a coupled elliptic-parabolic system. In particular, they show convergence rates of Lp-H1 (variational) regularization for the application under consideration via the use and verification of certain source and nonlinearity conditions. In computational practice, the Lp norm with p close to one is often used as a substitute for the actually sparsity promoting L1 norm. In Norm sensitivity of sparsity regularization with respect to p, Kamil S Kazimierski, Peter Maass and Robin Strehlow consider the question of how sensitive the Tikhonov regularized solution is with respect to p. They do so by computing the derivative via the implicit function theorem, particularly at the crucial value, p=1. Another iterative regularization method in Banach space is considered by Qinian Jin and Linda Stals in Nonstationary iterated Tikhonov regularization for ill-posed problems in Banach spaces. Using a variational formulation and under some smoothness and convexity assumption on the preimage space, they extend the convergence analysis of the well-known iterative Tikhonov method for linear problems in Hilbert space to a more general Banach

  1. Relevancia de la infección natural por Trypanosoma cruzi en triatominos selváticos provenientes de seis municipios de Santander, Colombia

    Directory of Open Access Journals (Sweden)

    Sergio Gómez

    2016-06-01

    genotipificación se realizó mediante PCR del espaciador intergénico del gen mini-exón (SL-IR, que amplifica fragmentos de 350 y 300 pb para T. cruzi I (TcI y T. cruzi II o V-VI (TcII-V-VI, respectivamente. Resultados: Se analizaron 50 especímenes adultos de Panstrongylus geniculatus (64% y Rhodnius pallescens (36% capturados principalmente en el domicilio y peridomicilio, respectivamente. La TI en los triatominos fue de 53,6% al examen directo y de 68,0% mediante PCR de satADN. La TI fue mayor para R. pallescens (77,8% en comparación con P. geniculatus (62,5%. Se observaron altas tasas de infección en triatominos provenientes de Floridablanca (90,9%, Bucaramanga (66,7% y Capitanejo (50,0%. En San Vicente de Chucurí y Lebrija también se detectaron altos índices de infección, no obstante, el número de vectores capturados en estos municipios fue muy bajo (entre 1 y 3. Se determinaron las DTUs de las poblaciones de T. cruzi presentes en el 41,2% de los triatominos selváticos positivos por PCR de satADN. En ambas especies vectoriales se evidenció el predominio de TcI (86% y una alta frecuencia (33% de infección mixta por TcI y TcII-V-VI en R. pallescens. Conclusiones: Se determinó la alta tasa de infección por T. cruzi en triatominos selváticos capturados en los municipios evaluados, lo cual resalta su importancia epidemiológica por la posibilidad de transmisión del parásito por vía oral, aún en zonas de baja endemia o donde no hay reporte de vectores domiciliados. Igualmente, es urgente la implementación de estrategias de control dirigidas a prevenir la intrusión domiciliaria de estos vectores.

  2. A systematic revision of Operclipygus Marseul (Coleoptera, Histeridae, Exosternini

    Directory of Open Access Journals (Sweden)

    Michael Caterino

    2013-02-01

    . panamensis (Wenzel & Dybas, 1941], O. sejunctus group [O. depressus (Hinton, 1935, O. itoupe sp. n., O. juninensis sp. n., O. pecki sp. n., O. punctiventer sp. n., O. sejunctus (Schmidt, 1896 comb. n., O. setiventris sp. n.], O. mortavis group [O. ecitonis sp. n., O. mortavis sp. n., O. paraguensis sp. n.], O. dytiscoides group [O. carinisternus sp. n., O. crenulatus sp. n., O. dytiscoides sp. n., O. quadratus sp. n.], O. dubitabilis group [O. dubitabilis (Marseul, 1889, O. yasuni sp. n.], O. angulifer group [O. angulifer sp. n., O. impressifrons sp. n.], O. dubius group [O. andinus sp. n., O. dubius (Lewis, 1888, O. extraneus sp. n., O. intermissus sp. n., O. lunulus sp. n., O. occultus sp. n., O. perplexus sp. n., O. remotus sp. n., O. validus sp. n., O. variabilis sp. n.], O. hospes group [O. assimilis sp. n., O. belemensis sp. n., O. bulbistoma sp. n., O. callifrons sp. n., O. colombicus sp. n., O. communis sp. n., O. confertus sp. n., O. confluens sp. n., O. curtistrius sp. n., O. diffluens sp. n., O. fusistrius sp. n., O. gratus sp. n., O. hospes (Lewis, 1902, O. ibiscus sp. n., O. ignifer sp. n., O. impositus sp. n., O. incisus sp. n., O. innocuus sp. n., O. inquilinus sp. n., O. minutus sp. n., O. novateutoniae sp. n., O. praecinctus sp. n., O. prominens sp. n., O. rileyi sp. n., O. subterraneus sp. n., O. tenuis sp. n., O. tiputinus sp. n.], O. farctus group [O. atlanticus sp. n., O. bidessois (Marseul, 1889, O. distinctus (Hinton, 1935, O. distractus (Schmidt, 1896 comb. n., O. farctissimus sp. n., O. farctus (Marseul, 1864, O. gilli sp. n., O. impressistrius sp. n., O. inflatus sp. n., O. latemarginatus (Bickhardt, 1920 comb. n., O. petrovi sp. n., O. plicatus (Hinton, 1935 comb. n., O. prolixus sp. n., O. punctifrons sp. n., O. proximus sp. n., O. subrufus sp. n.], O. hirsutipes group [O. guianensis sp. n., O. hirsutipes sp. n.], O. hamistrius group [O. arquus sp. n., O. campbelli sp. n., O. chiapensis sp. n., O. dybasi sp. n., O. geometricus (Casey, 1893 comb. n

  3. Yttrium-90 Needles in Interstitial Beta-Ray Therapy; Les Aiguilles d'Yttrium-90 en Endo-Electron-Therapie (Betatherapie Interstitielle); ИГЛЫ ИЗ ИТТРИЯ-90 ДЛЯ ЭНДОЭЛЕКТРОННОЙ ТЕРАПИИ ВНУТРИТКАНЕВОЙ БЕТА-ТЕРАГИ; Agujas de Itrio-90 en la Endo-Electronterapia (Betaterapia Intersticial)

    Energy Technology Data Exchange (ETDEWEB)

    Pierquin, B.; Mortreuil, M.; Beyer, H.; Dutreix, J.; Chassagne, D.; Galle, P.; Jammes, R. [Centre d' Etudes Nucleaires, Saclay (France)

    1963-03-15

    . Ishodnyj material. Igla sostoit iz neokisljajushhejsja stal'noj trubki diametrom 1 mm, dlinoj 30 - 40 mm pri tolshhine stenok 0,1 mm. Odin ee konec zakryt ostrokonechnym pvom, a drugoj - vystupajushhej golovkoj, pozvoljajushhej fiksirovat' nit' dlja izvlechenija igly. Cilindry ili zerna okisi ittrija (5 mm h 0,6 mm) podvergajutsja oblucheniju v techenie nedeli potokom v 2,7 * 10{sup 12} n/cm{sup 2}sek i zatem pomeshhajutsja po tri ili pjat' shtuk v kazhduju iz igl. Dozimetrija. Poluchennye iz centra Sakle ittrievye igly imejut standartnuju aktivnost' ot 1 do 1,5 mk/cm (radiacionnaja dlina). Aktivnost' odnovremenno kontroliruetsja schetchikom 4{pi} i na plenke densitometra. Otschetnaja doza opredeljaetsja standartnym obrazom s uchetom tolshhiny stenok trubki 2 mm i dopuskom, pri izvestnom priblizhenii rashoda dozy v 10 rad/min pri aktivnosti v 1 mk/sm. Terapevticheskoe primenenie. Radiobiologicheskoe dejstvie igl iz ittrija-90 eshhe slabo issledovano. Dejstvie igly bystro umen'shaetsja na rasstojanii svyshe 3 mm ot igly, chto zatrudnjaet gomogennoe obluchenie tkanej. Mozhno v principe predusmotret' raspolozhenie kazhdoj igly na rasstojanii v '' ili 6 mm odna ot drugoj, odnako, jeto trebuet nalichija ustrojstva dlja vzhivlenija pri sobljudenii tshhatel'nogo kontrolja. Pri oshibke v 1 ili 2 mm mogut vozniknut' znachitel'nye kolebanija dozy obluchenija. Vot pochemu avtory predusmotreli poka isaol'zovat' igly tol'ko dlja lechenija dobrokachestvennyh angiom, ve stremjao' pri jetom k gomogennomu v biologicheskom otnoshenii oblucheniju tkani, a starajas' lish' sozdat' zony skleroza, koncentricheski raspolagajushhiesja vozle igl, otdelennye zonami elabo idi oovoem ne obluchennyh tkanej. Davaja bol'nym preimushhestvenno ochen' slabye kumuljativnye dozy, avtory nadejutsja poduchit' takim putem sklerogennyj jeffekt, dostatochnyj dlja izlechenija nekotoryh angiom. Otsutstvie diffuzii v zdorovyh tkanjah imeet znachenie dlja angiom, nahodjashhihsja poblizooti ot radiochuvetvitel

  4. Experimental studies of some of the physical features of beryllium-moderated intermediate reactors; Etude experimentale de quelques particularites physiques des reacteurs a neutrons intermediaires, ralentis au beryllium; Ehksperimental'ny e issledovaniya nekotorykh fizicheskikh osobennostej promezhutochnykh reaktorov s berillievym zamedlitelem; Estudios experimentales de algunas caracteristicas fisicas de los reactores intermedios moderados con berilio

    Energy Technology Data Exchange (ETDEWEB)

    Lejpunskij, A I; Kuznetsov, V A; Artyukhov, G Ya; Mogil' ner, A I; Prokhorov, Yu A; Steklovski, V M; Chernov, L A [Akademiya Nauk, Moskva, Union of Soviet Socialist Republics (Russian Federation)

    1962-03-15

    la evaluacion de la eficacia de los cilindros compensadores giratorios distribuidos en el limite entre el cuerpo y el reflector. (author) [Russian] Doklad posvyashchen obzoru nekotorykh ehksperimen-tal'nykh rezul'tatov, poluchennykh na stende PF-4, prednaznachennom dlya detal'nogo issledovaniya fizicheskikh osobennostej reaktorov, rabotayushchikh na nejtronakh promezhutochnykh ehnergij. Aktivnye zony i otrazhateli razlichnykh kriticheskikh sborok predstavlyali soboj plotnuyu upakovku stal'nykh ili alyuminievykh trub, v kotorykh pomeshchalis' diski iz razlichnykh materialov. Kombinatsiya diskov urana (90%-nogo obogashcheniya) i zamedlyayushchikh materialov v razlichnoj proportsii, a takzhe vvedenie v otrazhatel' zamedlyayushchikh sloev razlichnoj tolshchiny, pozvolilo menyat' spektr nejtronov, proizvodyashchikh delenie, v ochen' shirokikh predelakh. V doklade privedeno opisanie stenda i ego otdel'nykh uzlov. Analiziruetsya sravnitel'naya ehffektivnost' vnutrennego i vneshnego zamedleniya dlya reaktorov s ochen'malym otnosheniem yader zamedlitelya i urana v aktivnoj zone. Ehksperimenty pokazyvayut, chto dazhe v sluchae tolstykh zamedlyayushchikh otrazhatelej maloe razbavlenie urana zamedlitelem (otnoshenie yader berilliya i urana-235 {partial_derivative}Be/{partial_derivative}U{sup 235}{approx_equal}1) privodit k vozrastaniyu kriticheskoj massy. Znachitel'noe mesto v doklade udeleno analizu geterogennykh ehffektov v promezhutochnykh reaktorakh. Pokazano, chto dlya reaktora s {partial_derivative}Be/{partial_derivative}U{sup 235}= 30+40, vysokoobogashchenny j uran v razlichnykh tolshchinakh ot 0,023 g/sm{sup 2} do 32 g/sm{sup 2} okazyvaet odinakovoe vliyanie na reaktiv-nost' sistemy. Analiziruyutsya prichiny, privodyashchie k kompensatsii ehffekta ehkranirovki nejtronnogo potoka tolstymi sloyami urana. V doklade privoditsya interesnyj fakt vozrastaniya ehffektivnosti urana vblizi po- gloshchayushchikh sterzhnej, ehksperimental'n o obnaruzhennyj v sbor kes {partial

  5. Neutron Spectra in H{sub 2}O, D{sub 2}O, BeO and CH{sub 2}; Spectres de Neutrons dans H{sub 2}O, D{sub 2}O, BeO et CH{sub 2}; Spektry nejtronov v H{sub 2}O, D{sub 2}O, BeO i CH{sub 2}; Espectros Neutronicos en H{sub 2}O, D{sub 2}O, BeO y CH{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Neill, J. M.; Young, J. C.; Trimble, G. D.; Beyster, J. R. [General Atomic Division of General Dynamics Corporation, John Jay Hopkins Laboratory for Pure and Applied Science, San Diego, CA (United States)

    1965-08-15

    tele. Neposredstvennye izmerenija byli soprjazheny s nekotorymi jeksperimental'nymi zatrudnenijami, kak, naprimer, poluchenie zhelatel'noj intensivnosti i razreshenija i vvedenie nadlezhashhih popravok na mnogokratnoe rassejanie v obrazce. S tochki zrenija primenenija k tehnologii reaktorov poslednij metod poluchenija jader rassejanija okazalsja vo mnogih sluchajah bolee, udovletvoritel'nym. Provedennye integral'nye izmerenija odnovremenno so sravnitel'nymi raschetami spektrov nejtronov pozvoljajut vyskazat'sja otnositel'no sostojatel'nosti teoreticheskih modelej rassejanija dlja N{sub 2}O, D{sub 2}O i VeO. Dajutsja ukazanija otnositel'no spektrov, zavisjashhih ot ugla i polozhenija, izmerejnyh v N{sub 2}O i D{sub 2}O i otravlennyh borom ili kadmiem; jeti danny'e ukazyvajut na uluchshenie soglasovannostiteoreticheskimi velichinami. Po-vidimomu, model' Nelkina dlja N{sub 2}O daet dostatochno udovletvoritel'noe v pervom priblizhenii opisanie rassejanija, proizvodimogo jetim zamedlitelem. Nuzhno takzhe dumat', cht.o model' Goneka dlja D{sub 2}O, javljajushhajasja rasprostraneniem nekogerentnoj modeli Nelkina dlja N{sub 2}O, takzhe javljaetsja udovletvoritel'nym opisaniem dlja nekotoryh vidov primenenija. Jeto predstavljaetsja udivitel'nym, tak kak v protivopolozhnost' vodorodu dejterij javljaetsja v bol'shinstve sluchaev kogerentnym rasseivajushhim veshhestvom, no jeto obstojatel'stvo podtverzhdaet nedavnee issledovanie Koppelja, kotoryj pokazal, chto vklady vnutrimolekuljarnyh i mezhmolekuljarnyh interferencij rassejanija v D{sub 2}O imejut tendenciju annulirovat' drug druga. V doklade privodjatsja takzhe poluchennye zamerom zavisjashhie ot ugla spektry nejtronov v VeO, otravlennoj borirovannoj nerzhavejushhej stal'ju. Voobshhe govorja, soglasovannost' izmerenij s raschetami byla znachitel'no uluchshena. Teoreticheskoe jadro rassejanija osnovano na debaevskom spektre chastoty, porog kotoroj byl otregulirovan takim obrazom, chtoby soglasovat'sja s izmerenijami udel

  6. Incorporation of Radioisotopes into Melted Silicates; Incorporation de Radioisotopes dans des Silicates Fondus; 0412 0412 0415 0414 0415 041d 0418 0415 0420 0410 0414 0418 041e 0418 0417 041e 0422 041e 041f 041e 0412 0412 0420 0410 0421 041f 041b 0410 0412 041b 0415 041d 041d 042b 0415 0421 0418 041b 0418 041a 0410 0422 042b ; Incorporacion de Radioisotopos en Silicatos Fundidos

    Energy Technology Data Exchange (ETDEWEB)

    Rakova, J.; Saidl, J. [Nuclear Research Institute Rez near Prague, Czechoslovak Socialist Republic (Czech Republic)

    1963-02-15

    vyshhelachivanija cezija i stroncija iz rasplavlennyh porod bol'shaja chast' vyshhelochennoj radioaktivnosti byla obnaruzhena v nachal'noj faze processa vyshhelachivanija-. Po istechenii 100 chasov process vyshhelachennyh radioizotopov stal postojannoj velichinoj. Skorost' vyshhelachivanija po istechenii prodolzhitel'nogo vremeni, verojatno, opredeljaetsja obshhej korrozionnoj stojkost'ju, a takzhe vnutrennej diffuziej rastvorimyh jelementov iz serediny tverdogo tela k poverhnosti. Korrozionnaja stojkost' stekla i rasplavlennyh porod izuchalas' v staticheskom sostojanii pri postojannoj temperature (35, 60 i 90 Degree-Sign C), i najdennye kojefficienty vyshhelachivanija byli v predelah 10{sup -11} -10{sup -9} cm{sup -2}sec{sup -1} (pri 35 Degree-Sign C). Jeti rezul'taty pokazyvajut, chto issledovavshiesja mineraly javljajutsja prigodnoj osnovoj dlja vvedenija nekotoryh vysokoaktivnyh othodov. Esli vysokoaktivnye othody budu udaljat'sja pri kontroliruemyh uslovijah, iskljuchajushhih kakoj-libo kontakt s vodoj, mozhno garantirovat' bezopasnost' jetogo udalenija. (author)

  7. Canadian Food Irradiation Facilities; Installations Canadiennes d'Irradiation des Aliments; Kanadskie ustanovki dlya oblucheniya pishchevykh produktov; Instalaciones de Irradiacion de Alimentos en el Canada

    Energy Technology Data Exchange (ETDEWEB)

    Warland, H. M.F.; MacQueen, K. F. [Atomic Energy of Canada Ltd., Commercial Products, Ottawa (Canada)

    1966-11-15

    programmy po kartofelju, KAOAJe pristupilo vmeste s kanadskimi issledovatel'skimi laboratorijami pishhevyh produktov k sovmestnym programmam issledovanij s primeneniem dopolnitel'nyh kamer dlja gamma-obluchenija. V 1960 godu KAOAJe skonstruirovalo ustanovku dlja obluchenija v jekranirovannom pome shhenii na svoem sobstvennom zavode v Ottave, chtoby obluchat' bolee, krupnye predmety, naprimer svinye okoroki i grozd'ja bananov. V 1963 godu, peredvizhnoj obluchatel', kotoryj i do jetogo byl naibolee poleznym sredstvom, stal bolee universal'nym za schet uvelichenija moshhnosti istochnika i osnashhenija sistemoj ohlazhdenija produktov i ustanovkoj dlja kondicionirovanija vozduha v avtofurgone. Posle jetih modifikacij ustanovka ispol'zovalas' v Kalifornii dlja obluchenija raznoobraznyh fruktov na opytnoj stancii ministerstva sel'skogo hozjajstva SShA v Fresno. Daetsja podrobnoe opisanie kamery dlja gamma-obluchenija, peredvizhnogo obluchatelja, ustanovki v jekranirovannom pomeshhenii, promyshlennogo obluchatelja pishhevyh produktov, a takzhe nekotoryh osnovnyh programm issledovanij pishhevyh produktov. V nastojashhee vremja predprijatija pishhevoj promyshlennosti projavljajut vse bol'shij interes k oblucheniju produktov, i perspektivy ispol'zovanija budushhih ustanovok javljajutsja blagoprijatnymi. (author)

  8. Short-Lived Isotopes Used as Tracers in Industry (with Special Reference to Swedish Industry); Emploi de Radioindicateurs de Courte Periode a l'Echelle Industrielie dans les Usines Suedoises; ПРИМЕНЕНИЕ КОРОТКОЖИВУЩИХ ИЗОТОПОВ В ПРОМЫШЛЕННОСТИ В КАЧЕСТВЕ МЕЧЕНЫХ АТОМОВ; Isotopos de Periodo Corto Utilizados Como Indicadores en la Industria Sueca

    Energy Technology Data Exchange (ETDEWEB)

    Erwall, L. G.; Forsberg, H. G.; Ljunggren, K. [Isotoptekniska Laboratoriet, Stockholm (Sweden)

    1963-03-15

    prestar asistencia a las empresas industriales proporcionandoles asesoiamiento, personal y los instrumentos necesarios para las aplicaciones industriales de los radioisotopos. (author) [Russian] Metody radioaktivnyh mechenyh atomov bystro nahodjat svoe priznanie kak neocenimoe sredstvo dlja issledovanij i kontrolja v promyshlennosti. Oni uhe uspeshno primenjalis' v avarijnyh sluchajah, pri issle- dovanii harakteristik proizvodstvennyh uzlov i kak vspomogatel'noe sredstvo pri konstruirovanii takih proizvodstvennyh uzlov. Dannyj obzor soderzhit tipichnye primery primenenija korotkozhivushhih mechenyh atomov, kotorye mogut byt' polucheny v umerennyh nejtronnyh potokah, naprimer,natrija-24, magnija-56, broma-62, lantana-140, a takzhe hlora-38, kalija-42 i zolota-196. S pomoshh'ju korotkozhivushhih izotopov mozhno proizvodit': - izuchenie prohozhdenija tverdyh veshhestv cherez proizvodstvennye uzly (vrashhavshiesja sushil'nye pechi, domennye pechi, celljuloznye avtoklavy, bashni dlja otbelki, sgustiteli Dorra) ; - opredelenie skorosti potoka zhidkostej v trubah i v otkrytyh ruslah (naprimer, dlja izmerenija obshego kolichestva potreblenija vody na ustanovke); - opredelenie vremeni nahozhdenija zaderzhki i ob{sup e}ma zhidkostej v razlichnyh tehnologicheskih uzlah v celljuloznoj i bumazhnoj promyshlennosti - ''vzveshivanie'' po metodu izotopnogo razbavlenija dlja opredelenija kolichestva shlakov v martenovskih pechah; - opredelenie proishozhdenija nemetallicheskih primesej v stali dlja izyskanija luchshih materialov dlja oblicovki i dlja usovershenstvovanija metodov otlivki; - mechenie dlja opredelenija kachestva, pozvoljajushhee ustanovit' s absoljutnoj dostovernost'ju jeksperimental'nye stal'nye plavki i specificheskie materialy v chernoj metallurgii; - opredelenie jeffektivnosti mesilok v betonnoj promyshlennosti; - sostavlenie diagramm potoka v bassejnah dlja stochnyh vod ili zhidkih othodov v celjah nahozhdenija nailuchshego mesta dlja spuska takih zhidkostej

  9. Determination of Fallout Radionuclides in Environmental Samples by Gamma-Ray Spectrometry; Mesure Spectrometrique Gamma des Radionucleides de Retombee Presents dans des Echantillons du Millieu; Opredelenie radioizotopov radioaktivnykh osadkov v probakh iz okruzhayushchej sredy pri pomoshchi spektrometrii gamma-luchej; Determinacion, por Espectrometria Gamma, de los Radionuclidos de Precipitaciones en Muestras del Medio Ambiente

    Energy Technology Data Exchange (ETDEWEB)

    Ward, G. M.; Johnson, J. E.; Wilson, D. W. [Department of Animal Science, Colorado State University, Fort Collins, CO (United States)

    1965-10-15

    vremeni na universitetskoj ferme sobrali znachitel'noe kolichestvo prob iz okruzhajushhej sredy dlja izuchenija dvizhenija cezija-137 v znachitel'noj chasti pishhevoj ce- pochki cheloveka. Vse proby imeli maluju udel'nuju aktivnost', i izmerenija proizvodili pri pomoshhi spektrometricheskogo ustrojstva dlja gamma-luchej nizkogo urovnja, sostojashhego iz kristalla NaJ (T1) diametrom 8 i tolshhinoj 4 djujma, prichem jetot kristall byl zashhishhen ot fona stal'noj kameroj s tolshhinoj stenok 5 djujmov i soedinen s 400-kanal'nym anali- zatorom amplitudy impul'sov. Otschet nabivok vozdushnyh fil'trov i krupnyh prob ( 1kg) suhogo furazha, zerna i pometa krupnogo rogatog o skota proizvodili neposredstvenno v postojannoj geometrii. Proby osadkov koncentrirovali propuskaniem ih cherez kationo- obmennye kolonki, zapolnennye doveksom-50. Radioaktivnost' moloka, mjasa i mochi pod- schityvali v bol'shih kol'ceobraznyh kontejnerah iz ljucita. V moloke, mjase i moche ob- naruzhivajutsja v chisle gamma-izluchajushhih radioizotopov lish' cezij-137, kalij-40, jod-131, barij-140 i lantan-140, poskol'ku oni javljajutsja edinstvennymi produktami delenija, po- gloshhaemymi v znachitel'nyh kolichestvah. Pomimo jetogo, drugie proby soderzhali cezij-141, cezij-144, sur'mu-125, rutenij-103, rutenij-106, cirkonij-95, niobij-95 i marganec-54. V probah, sobrannyh v 1962 i 1963 godah, pri pomoshhi'gamma-spektrometrii udalos' oprede- lenno obnaruzhit' lish' cirk{sup n}ij-95 i niobij-95 vvidu ih otnositel'nogo obilija; jeto bylo prodelano priblizitel'no za 6 mesjacev posle sbora prob. Fotopiki cezija-137, marganca-54 i sur'my-125 byli sovershenno rasplyvchatymi, a radioizotopy bolee malyh jenergij (cezij-141, cezij-144 i rutenij-103) imeli znachitel'nye komptonovskie vklady ot radio- izotopov bolee vysokih jenergij. Pri nedostatochno jasnyh fotopikah posledovatel'noe vydelenie produktov delenija iz spektrov ne javljaetsja nadezhnym. Kogda vlijanie drugih radioizotopov delaet nevozmozhnym

  10. Fabrication and Testing of Prototype APM-Clad UO{sub 2} Fuel Elements; Fabrication et essai de prototypes de cartouches de combustible en bioxyde d'uranium gaine d'aluminium (APM); Izgotovlenie i ispytanie prototipa toplivnykh ehlementov na osnove UO{sub 2} s obolochkoj iz alyuminiya metodom poroshkovoj metallurgii; Elaboracion y ensayo de elementos combustibles prototipo de UO{sub 2} con revestimiento de aluminio sinterizado

    Energy Technology Data Exchange (ETDEWEB)

    Ballif, III, J. L.; Friske, W. H.; Gordon, R. B. [Atomics International, Canoga Park, California (United States)

    1963-11-15

    los elementos combustibles se extrajeron del reactor a raiz de problemas suscitados por el instrumental utilizado para los ensayos. Los tres elementos restantes continuaban en el reactor. Todos los resultados de los experimentos realizados hasta la fecha parecen indicar que el sistema de combustible PMA-UO{sub 2} permitira alcanzar los objetivos fijados para el programa relativo al reactor POPR. (author) [Russian] V podderzhku Programmy prototipov organicheskikh ehnergoreaktorov (POPR) moshchnost'yu 50 mgvt (ehl.) byla provedena obshirnaya rabota po razrabotke poroshkovoj metallurgiej alyuminievykh materialov (APM) v kachestve obolochek dlya topliva iz UO{sub 2} . Kak chast' ehtoj raboty byli issledovany ehvteticheskoe soedinenie, svarke v styk oplavleniem i kholodnaya svarka. Kolduehlla pod davleniem kak metody dlya soedineniya stykov pri sborke toplivnykh ehlementov. Vibratsionnoe uplotnenie izuchalos' kak sredstvo zapolneniya trubok APM dvuokis'yu urana. Opyty vne reaktora provodilis' dlya.ogo, chtoby poluchit' informatsiyu o svomestimosti APM - UO{sub 2} . Ehta rabota pokazala, chto pri sushchestvuyushchikh usloviyakh ehvteticheskoe soedinenie yavlyaetsya naibolee podkhodyashchim sposobom dlya soedineniya stykov; vibratsionnoe uplotnenie davalo plotnost' topliva v predelakh ot 80 do 88% teoreticheskoj plotnosti, i ne nablyudalos' vzaimodejstvie APM -UO{sub 2} v diapazone ehkspluatatsionnykh temperatur POPR (temperatura poverkhnosti razdela toplivo - obolochka maksimum 850{sup o}F). V rezul'tate ehtoj raboty bylo izgotovleno 5 prototipov UO{sub 2}-APM toplivnykh ehlementov s tsel'yu ispytaniya na opytnom reaktore s organicheskim zamedlitelem. Kazhdyj ehlement sostoyal iz 24 ili 25 toplivnykh sterzhnej v obolochke iz APM i sgruppirovannykh v sistemu 5 x 5 v stal'noj korobke, pokrytoj nikelem, ili toplivnoj korobke ieh APM. Dlya togo, chtoby uvelichit' poverkhnost' ehlementa i tem samym znachitel'no uluchshit' teploperedachu, izgotovlennaya ehkstruziej obolochka ieh