WorldWideScience

Sample records for flies trypanosomes humans

  1. Through the dark continent: African trypanosome developments in the tsetse fly

    Directory of Open Access Journals (Sweden)

    Brice eROTUREAU

    2013-09-01

    Full Text Available African trypanosomes are unicellular flagellated parasites causing trypanosomiases in Africa, a group of severe diseases also known as sleeping sickness in human and nagana in cattle. These parasites are almost exclusively transmitted by the bite of the tsetse fly. In this review, we describe and compare the three development programs of the main trypanosome species impacting human and animal health, with focus on the most recent observations. From here, some reflections on research issues on the trypanosome developmental biology in the tsetse fly to be addressed in the future are given.

  2. The bacterial flora of tsetse fly midgut and its effect on trypanosome transmission

    OpenAIRE

    Soumana, I. H.; Simo, G.; Njiokou, F.; Tchicaya, B.; Abd-Alla, A.M.M.; Cuny, Gérard; Geiger, Anne

    2013-01-01

    The tsetse fly, Glossina palpalis is a vector of the trypanosome that causes sleeping sickness in humans and nagana in cattle along with associated human health problems and massive economic losses. The insect is also known to carry a number of symbionts such as Sodalis, Wigglesworthia, Wolbachia whose effects on the physiology of the insect have been studied in depth. However, effects of other bacterial flora on the physiology of the host and vector competence have received little attention....

  3. A co-evolutionary arms race: trypanosomes shaping the human genome, humans shaping the trypanosome genome

    OpenAIRE

    Capewell, Paul; Cooper, Anneli; Clucas, Caroline; Weir, William; MacLeod, Annette

    2014-01-01

    Trypanosoma brucei is the causative agent of African sleeping sickness in humans and one of several pathogens that cause the related veterinary disease Nagana. A complex co-evolution has occurred between these parasites and primates that led to the emergence of trypanosome-specific defences and counter-measures. The first line of defence in humans and several other catarrhine primates is the trypanolytic protein apolipoprotein-L1 (APOL1) found within two serum protein complexes, trypanosome l...

  4. A tsetse and tabanid fly survey of African great apes habitats reveals the presence of a novel trypanosome lineage but the absence of Trypanosoma brucei.

    Science.gov (United States)

    Votýpka, Jan; Rádrová, Jana; Skalický, Tomáš; Jirků, Milan; Jirsová, Dagmar; Mihalca, Andrei D; D'Amico, Gianluca; Petrželková, Klára J; Modrý, David; Lukeš, Julius

    2015-10-01

    Tsetse and tabanid flies transmit several Trypanosoma species, some of which are human and livestock pathogens of major medical and socioeconomic impact in Africa. Recent advances in molecular techniques and phylogenetic analyses have revealed a growing diversity of previously unidentified tsetse-transmitted trypanosomes potentially pathogenic to livestock and/or other domestic animals as well as wildlife, including African great apes. To map the distribution, prevalence and co-occurrence of known and novel trypanosome species, we analyzed tsetse and tabanid flies collected in the primary forested part of the Dzanga-Sangha Protected Areas, Central African Republic, which hosts a broad spectrum of wildlife including primates and is virtually devoid of domestic animals. Altogether, 564 tsetse flies and 81 tabanid flies were individually screened for the presence of trypanosomes using 18S rRNA-specific nested PCR. Herein, we demonstrate that wildlife animals are parasitized by a surprisingly wide range of trypanosome species that in some cases may circulate via these insect vectors. While one-third of the examined tsetse flies harbored trypanosomes either from the Trypanosoma theileri, Trypanosoma congolense or Trypanosoma simiae complex, or one of the three new members of the genus Trypanosoma (strains 'Bai', 'Ngbanda' and 'Didon'), more than half of the tabanid flies exclusively carried T. theileri. To establish the putative vertebrate hosts of the novel trypanosome species, we further analyzed the provenance of blood meals of tsetse flies. DNA individually isolated from 1033 specimens of Glossina spp. and subjected to high-throughput library-based screening proved that most of the examined tsetse flies engorged on wild ruminants (buffalo, sitatunga, bongo), humans and suids. Moreover, they also fed (albeit more rarely) on other vertebrates, thus providing indirect but convincing evidence that trypanosomes can be transmitted via these vectors among a wide range of

  5. Trypanosome infection establishment in the tsetse fly gut is influenced by microbiome-regulated host immune barriers.

    Directory of Open Access Journals (Sweden)

    Brian L Weiss

    Full Text Available Tsetse flies (Glossina spp. vector pathogenic African trypanosomes, which cause sleeping sickness in humans and nagana in domesticated animals. Additionally, tsetse harbors 3 maternally transmitted endosymbiotic bacteria that modulate their host's physiology. Tsetse is highly resistant to infection with trypanosomes, and this phenotype depends on multiple physiological factors at the time of challenge. These factors include host age, density of maternally-derived trypanolytic effector molecules present in the gut, and symbiont status during development. In this study, we investigated the molecular mechanisms that result in tsetse's resistance to trypanosomes. We found that following parasite challenge, young susceptible tsetse present a highly attenuated immune response. In contrast, mature refractory flies express higher levels of genes associated with humoral (attacin and pgrp-lb and epithelial (inducible nitric oxide synthase and dual oxidase immunity. Additionally, we discovered that tsetse must harbor its endogenous microbiome during intrauterine larval development in order to present a parasite refractory phenotype during adulthood. Interestingly, mature aposymbiotic flies (Gmm(Apo present a strong immune response earlier in the infection process than do WT flies that harbor symbiotic bacteria throughout their entire lifecycle. However, this early response fails to confer significant resistance to trypanosomes. Gmm(Apo adults present a structurally compromised peritrophic matrix (PM, which lines the fly midgut and serves as a physical barrier that separates luminal contents from immune responsive epithelial cells. We propose that the early immune response we observe in Gmm(Apo flies following parasite challenge results from the premature exposure of gut epithelia to parasite-derived immunogens in the absence of a robust PM. Thus, tsetse's PM appears to regulate the timing of host immune induction following parasite challenge. Our results

  6. A phylogenetic lineage of closely related trypanosomes (Trypanosomatidae, Kinetoplastida) of anurans and sand flies (Psychodidae, Diptera) sharing the same ecotopes in brazilian amazonia.

    Science.gov (United States)

    Ferreira, Robson C; De Souza, Adelson A; Freitas, Rui A; Campaner, Marta; Takata, Carmem S A; Barrett, Toby V; Shaw, Jeffrey J; Teixeira, Marta M G

    2008-01-01

    Analysis of the phylogenetic relationships among trypanosomes from vertebrates and invertebrates disclosed a new lineage of trypanosomes circulating among anurans and sand flies that share the same ecotopes in Brazilian Amazonia. This assemblage of closely related trypanosomes was determined by comparing whole SSU rDNA sequences of anuran trypanosomes from the Brazilian biomes of Amazonia, the Pantanal, and the Atlantic Forest and from Europe, North America, and Africa, and from trypanosomes of sand flies from Amazonia. Phylogenetic trees based on maximum likelihood and parsimony corroborated the positioning of all new anuran trypanosomes in the aquatic clade but did not support the monophyly of anuran trypanosomes. However, all analyses always supported four major clades (An01-04) of anuran trypanosomes. Clade An04 is composed of trypanosomes from exotic anurans. Isolates in clades An01 and An02 were from Brazilian frogs and toads captured in the three biomes studied, Amazonia, the Pantanal and the Atlantic Forest. Clade An01 contains mostly isolates from Hylidae whereas clade An02 comprises mostly isolates from Bufonidae; and clade An03 contains trypanosomes from sand flies and anurans of Bufonidae, Leptodactylidae, and Leiuperidae exclusively from Amazonia. To our knowledge, this is the first study describing morphological and growth features, and molecular phylogenetic affiliation of trypanosomes from anurans and phlebotomines, incriminating these flies as invertebrate hosts and probably also as important vectors of Amazonian terrestrial anuran trypanosomes.

  7. The Evolution of Trypanosomes Infecting Humans and Primates

    Directory of Open Access Journals (Sweden)

    Stevens Jamie

    1998-01-01

    Full Text Available Based on phylogenetic analysis of 18S rRNA sequences and clade taxon composition, this paper adopts a biogeographical approach to understanding the evolutionary relationships of the human and primate infective trypanosomes, Trypanosoma cruzi, T. brucei, T. rangeli and T. cyclops. Results indicate that these parasites have divergent origins and fundamentally different patterns of evolution. T. cruzi is placed in a clade with T. rangeli and trypanosomes specific to bats and a kangaroo. The predominantly South American and Australian origins of parasites within this clade suggest an ancient southern super-continent origin for ancestral T. cruzi, possibly in marsupials. T. brucei clusters exclusively with mammalian, salivarian trypanosomes of African origin, suggesting an evolutionary history confined to Africa, while T. cyclops, from an Asian primate appears to have evolved separately and is placed in a clade with T. (Megatrypanum species. Relating clade taxon composition to palaeogeographic evidence, the divergence of T. brucei and T. cruzi can be dated to the mid-Cretaceous, around 100 million years before present, following the separation of Africa, South America and Euramerica. Such an estimate of divergence time is considerably more recent than those of most previous studies based on molecular clock methods. Perhaps significantly, Salivarian trypanosomes appear, from these data, to be evolving several times faster than Schizotrypanum species, a factor which may have contributed to previous anomalous estimates of divergence times.

  8. Trypanosomes - versatile microswimmers

    Science.gov (United States)

    Krüger, Timothy; Engstler, Markus

    2016-11-01

    Evolution has generated a plethora of flagellate microswimmers. They populate all natural waters, from the deep sea to the ponds in our neighbourhood. But flagellates also thrive in the bodies of higher organisms, where they mostly remain undetected, but can also become pathogenic. Trypanosomes comprise a large group of mostly parasitic flagellates that cause many diseases, such as human sleeping sickness or the cattle plague nagana. We consider African trypanosomes as extremely versatile microswimmers, as they have to adapt to very diverse microenvironments. They swim efficiently in the blood of their mammalian hosts, but also in various tissue spaces and even in the human brain. Furthermore, in the transmitting tsetse fly, trypanosomes undergo characteristic morphological changes that are accompanied by amazing transitions between solitary and collective types of motion. In this review, we provide a basic introduction to trypanosome biology and then focus on the complex type of rotational movement that trypanosomes display. We relate their swimming performance to morphological parameters and the respective microenvironment, developing a contemporary view on the physics of trypanosome motility. The genetically programmed successions of life style-dependent motion patterns provide challenges and opportunities for interdisciplinary studies of microswimmers.

  9. Identification of different trypanosome species in the mid-guts of tsetse flies of the Malanga (Kimpese sleeping sickness focus of the Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Simo Gustave

    2012-09-01

    Full Text Available Abstract Background The Malanga sleeping sickness focus of the Democratic Republic of Congo has shown an epidemic evolution of disease during the last century. However, following case detection and treatment, the prevalence of the disease decreased considerably. No active survey has been undertaken in this focus for a couple of years. To understand the current epidemiological status of sleeping sickness as well as the animal African trypanosomiasis in the Malanga focus, we undertook the identification of tsetse blood meals as well as different trypanosome species in flies trapped in this focus. Methods Pyramidal traps were use to trap tsetse flies. All flies caught were identified and live flies were dissected and their mid-guts collected. Fly mid-gut was used for the molecular identification of the blood meal source, as well as for the presence of different trypanosome species. Results About 949 Glossina palpalis palpalis were trapped; 296 (31.2% of which were dissected, 60 (20.3% blood meals collected and 57 (19.3% trypanosome infections identified. The infection rates were 13.4%, 5.1%, 3.5% and 0.4% for Trypanosoma congolense savannah type, Trypanosoma brucei s.l., Trypanosoma congolense forest type and Trypanosoma vivax, respectively. Three mixed infections including Trypanosoma brucei s.l. and Trypanosoma congolense savannah type, and one mixed infection of Trypanosoma vivax and Trypanosoma congolense savannah type were identified. Eleven Trypanosoma brucei gambiense infections were identified; indicating an active circulation of this trypanosome subspecies. Of all the identified blood meals, about 58.3% were identified as being taken on pigs, while 33.3% and 8.3% were from man and other mammals, respectively. Conclusion The presence of Trypanosoma brucei in tsetse mid-guts associated with human blood meals is indicative of an active transmission of this parasite between tsetse and man. The considerable number of pig blood meals combined

  10. Identification of different trypanosome species in the mid-guts of tsetse flies of the Malanga (Kimpese) sleeping sickness focus of the Democratic Republic of Congo.

    Science.gov (United States)

    Simo, Gustave; Silatsa, Barberine; Flobert, Njiokou; Lutumba, Pascal; Mansinsa, Philemon; Madinga, Joule; Manzambi, Emile; De Deken, Reginald; Asonganyi, Tazoacha

    2012-09-19

    The Malanga sleeping sickness focus of the Democratic Republic of Congo has shown an epidemic evolution of disease during the last century. However, following case detection and treatment, the prevalence of the disease decreased considerably. No active survey has been undertaken in this focus for a couple of years. To understand the current epidemiological status of sleeping sickness as well as the animal African trypanosomiasis in the Malanga focus, we undertook the identification of tsetse blood meals as well as different trypanosome species in flies trapped in this focus. Pyramidal traps were use to trap tsetse flies. All flies caught were identified and live flies were dissected and their mid-guts collected. Fly mid-gut was used for the molecular identification of the blood meal source, as well as for the presence of different trypanosome species. About 949 Glossina palpalis palpalis were trapped; 296 (31.2%) of which were dissected, 60 (20.3%) blood meals collected and 57 (19.3%) trypanosome infections identified. The infection rates were 13.4%, 5.1%, 3.5% and 0.4% for Trypanosoma congolense savannah type, Trypanosoma brucei s.l., Trypanosoma congolense forest type and Trypanosoma vivax, respectively. Three mixed infections including Trypanosoma brucei s.l. and Trypanosoma congolense savannah type, and one mixed infection of Trypanosoma vivax and Trypanosoma congolense savannah type were identified. Eleven Trypanosoma brucei gambiense infections were identified; indicating an active circulation of this trypanosome subspecies. Of all the identified blood meals, about 58.3% were identified as being taken on pigs, while 33.3% and 8.3% were from man and other mammals, respectively. The presence of Trypanosoma brucei in tsetse mid-guts associated with human blood meals is indicative of an active transmission of this parasite between tsetse and man. The considerable number of pig blood meals combined with the circulation of Trypanosoma brucei gambiense in this focus

  11. Trypanosomes Infection in Field-Captured Tsetse Flies of the Subgenus: Nemorhina In Southern Guinea Savanna Zone of Nigeria

    Directory of Open Access Journals (Sweden)

    K.E. Okoh

    2012-11-01

    Full Text Available An investigation aimed at assessing the Trypanosomes infection in the Palpalis group was conducted between January and December of 2007 at Kamuku National Park, using Biconical and Nitse traps. Flies were trapped along riverine vegetation for two trapping days each month and were harvested daily. Out of 213 tsetse flies examined, 14 (6.6% were infected with trypanosome. Infection rate in G. tachinoides 9.4% (11 out of 117 were statistically (p<0.05 higher than G. Palpalis 3.1% (3 out of 96 flies examined. Also, infection rate were higher in males 5.2% (11 than females 1.4% (3. Infection due to Trypanosoma vivax 5.2% (11 dominated, followed by T. congolense 0.9% (2 then T. brucei 0.5% (1. The Mean Hunger Stages of 3.5 and 3.6 for G. tachinoides and G. palpalis respectively indicated a hungry population. Infections were highest in the month of May. The presence of Tsetse and Trypanosome infection in the park may pose public health risk.

  12. Hemoglobin is a co-factor of human trypanosome lytic factor

    DEFF Research Database (Denmark)

    Widener, Justin; Nielsen, Marianne Jensby; Shiflett, April

    2007-01-01

    by increasing the affinity of TLF for its receptor, and by inducing Fenton chemistry within the trypanosome lysosome. These findings suggest that TLF in uninfected humans may be inactive against T. b. brucei prior to initiation of infection. We propose that infection of humans by T. b. brucei causes hemolysis...

  13. Social motility of African trypanosomes is a property of a distinct life-cycle stage that occurs early in tsetse fly transmission.

    Science.gov (United States)

    Imhof, Simon; Knüsel, Sebastian; Gunasekera, Kapila; Vu, Xuan Lan; Roditi, Isabel

    2014-10-01

    The protozoan pathogen Trypanosoma brucei is transmitted between mammals by tsetse flies. The first compartment colonised by trypanosomes after a blood meal is the fly midgut lumen. Trypanosomes present in the lumen-designated as early procyclic forms-express the stage-specific surface glycoproteins EP and GPEET procyclin. When the trypanosomes establish a mature infection and colonise the ectoperitrophic space, GPEET is down-regulated, and EP becomes the major surface protein of late procyclic forms. A few years ago, it was discovered that procyclic form trypanosomes exhibit social motility (SoMo) when inoculated on a semi-solid surface. We demonstrate that SoMo is a feature of early procyclic forms, and that late procyclic forms are invariably SoMo-negative. In addition, we show that, apart from GPEET, other markers are differentially expressed in these two life-cycle stages, both in culture and in tsetse flies, indicating that they have different biological properties and should be considered distinct stages of the life cycle. Differentially expressed genes include two closely related adenylate cyclases, both hexokinases and calflagins. These findings link the phenomenon of SoMo in vitro to the parasite forms found during the first 4-7 days of a midgut infection. We postulate that ordered group movement on plates reflects the migration of parasites from the midgut lumen into the ectoperitrophic space within the tsetse fly. Moreover, the process can be uncoupled from colonisation of the salivary glands. Although they are the major surface proteins of procyclic forms, EP and GPEET are not essential for SoMo, nor, as shown previously, are they required for near normal colonisation of the fly midgut.

  14. Social motility of African trypanosomes is a property of a distinct life-cycle stage that occurs early in tsetse fly transmission.

    Directory of Open Access Journals (Sweden)

    Simon Imhof

    2014-10-01

    Full Text Available The protozoan pathogen Trypanosoma brucei is transmitted between mammals by tsetse flies. The first compartment colonised by trypanosomes after a blood meal is the fly midgut lumen. Trypanosomes present in the lumen-designated as early procyclic forms-express the stage-specific surface glycoproteins EP and GPEET procyclin. When the trypanosomes establish a mature infection and colonise the ectoperitrophic space, GPEET is down-regulated, and EP becomes the major surface protein of late procyclic forms. A few years ago, it was discovered that procyclic form trypanosomes exhibit social motility (SoMo when inoculated on a semi-solid surface. We demonstrate that SoMo is a feature of early procyclic forms, and that late procyclic forms are invariably SoMo-negative. In addition, we show that, apart from GPEET, other markers are differentially expressed in these two life-cycle stages, both in culture and in tsetse flies, indicating that they have different biological properties and should be considered distinct stages of the life cycle. Differentially expressed genes include two closely related adenylate cyclases, both hexokinases and calflagins. These findings link the phenomenon of SoMo in vitro to the parasite forms found during the first 4-7 days of a midgut infection. We postulate that ordered group movement on plates reflects the migration of parasites from the midgut lumen into the ectoperitrophic space within the tsetse fly. Moreover, the process can be uncoupled from colonisation of the salivary glands. Although they are the major surface proteins of procyclic forms, EP and GPEET are not essential for SoMo, nor, as shown previously, are they required for near normal colonisation of the fly midgut.

  15. Trypanosomes of non-human primates from the National Centre of Primates, Ananindeua, State of Pará, Brazil

    Directory of Open Access Journals (Sweden)

    Ziccardi Mariangela

    2000-01-01

    Full Text Available Trypanosome infections were sought in 46 non-human primates captured principally in Amazonian Brazil. Twenty-two (47.8% were infected with four Trypanosoma species: T. cruzi, T. minasense, T. devei and T. rangeli. These preliminary results confirmed the high prevalence and diversity of natural infections with trypanosomes in primates from Brazilian Amazon and were the first formal record of simian infections with trypanosomes in the State of Acre. The presence of T. cruzi-like and T. rangeli-like parasites are recorded in four new hosts.

  16. Protease activated receptor signaling is required for African trypanosome traversal of human brain microvascular endothelial cells.

    Directory of Open Access Journals (Sweden)

    Dennis J Grab

    Full Text Available BACKGROUND: Using human brain microvascular endothelial cells (HBMECs as an in vitro model for how African trypanosomes cross the human blood-brain barrier (BBB we recently reported that the parasites cross the BBB by generating calcium activation signals in HBMECs through the activity of parasite cysteine proteases, particularly cathepsin L (brucipain. In the current study, we examined the possible role of a class of protease stimulated HBMEC G protein coupled receptors (GPCRs known as protease activated receptors (PARs that might be implicated in calcium signaling by African trypanosomes. METHODOLOGY/PRINCIPAL FINDINGS: Using RNA interference (RNAi we found that in vitro PAR-2 gene (F2RL1 expression in HBMEC monolayers could be reduced by over 95%. We also found that the ability of Trypanosoma brucei rhodesiense to cross F2RL1-silenced HBMEC monolayers was reduced (39%-49% and that HBMECs silenced for F2RL1 maintained control levels of barrier function in the presence of the parasite. Consistent with the role of PAR-2, we found that HBMEC barrier function was also maintained after blockade of Galpha(q with Pasteurella multocida toxin (PMT. PAR-2 signaling has been shown in other systems to have neuroinflammatory and neuroprotective roles and our data implicate a role for proteases (i.e. brucipain and PAR-2 in African trypanosome/HBMEC interactions. Using gene-profiling methods to interrogate candidate HBMEC pathways specifically triggered by brucipain, several pathways that potentially link some pathophysiologic processes associated with CNS HAT were identified. CONCLUSIONS/SIGNIFICANCE: Together, the data support a role, in part, for GPCRs as molecular targets for parasite proteases that lead to the activation of Galpha(q-mediated calcium signaling. The consequence of these events is predicted to be increased permeability of the BBB to parasite transmigration and the initiation of neuroinflammation, events precursory to CNS disease.

  17. Hemoglobin is a co-factor of human trypanosome lytic factor.

    Directory of Open Access Journals (Sweden)

    Justin Widener

    2007-09-01

    Full Text Available Trypanosome lytic factor (TLF is a high-density lipoprotein (HDL subclass providing innate protection to humans against infection by the protozoan parasite Trypanosoma brucei brucei. Two primate-specific plasma proteins, haptoglobin-related protein (Hpr and apolipoprotein L-1 (ApoL-1, have been proposed to kill T. b. brucei both singularly or when co-assembled into the same HDL. To better understand the mechanism of T. b. brucei killing by TLF, the protein composition of TLF was investigated using a gentle immunoaffinity purification technique that avoids the loss of weakly associated proteins. HDL particles recovered by immunoaffinity absorption, with either anti-Hpr or anti-ApoL-1, were identical in protein composition and specific activity for T. b. brucei killing. Here, we show that TLF-bound Hpr strongly binds Hb and that addition of Hb stimulates TLF killing of T. b. brucei by increasing the affinity of TLF for its receptor, and by inducing Fenton chemistry within the trypanosome lysosome. These findings suggest that TLF in uninfected humans may be inactive against T. b. brucei prior to initiation of infection. We propose that infection of humans by T. b. brucei causes hemolysis that triggers the activation of TLF by the formation of Hpr-Hb complexes, leading to enhanced binding, trypanolytic activity, and clearance of parasites.

  18. The trypanosome Rab-related proteins RabX1 and RabX2 play no role in intracellular trafficking but may be involved in fly infectivity.

    Directory of Open Access Journals (Sweden)

    Senthil Kumar A Natesan

    Full Text Available BACKGROUND: Rab GTPases constitute the largest subgroup of the Ras superfamily and are primarily involved in vesicle targeting. The full extent of Rab family function is unexplored. Several divergent Rab-like proteins are known but few have been characterized. In Trypanosoma brucei there are sixteen Rab genes, but RabX1, RabX2 and RabX3 are divergent within canonical sequence regions. Where known, trypanosome Rab functions are broadly conserved when orthologous relationships may be robustly established, but specific functions for RabX1, X2 and X3 have yet to be determined. RabX1 and RabX2 originated via tandem duplication and subcellular localization places RabX1 at the endoplasmic reticulum, while RabX2 is at the Golgi complex, suggesting distinct functions. We wished to determine whether RabX1 and RabX2 are involved in vesicle transport or other cellular processes. METHODOLOGY/PRINCIPAL FINDINGS: Using comparative genomics we find that RabX1 and RabX2 are restricted to trypanosomatids. Gene knockout indicates that RabX1 and RabX2 are non-essential. Simultaneous RNAi knockdown of both RabX1 and RabX2, while partial, was also non-lethal and may suggest non-redundant function, consistent with the distinct locations of the proteins. Analysis of the knockout cell lines unexpectedly failed to uncover a defect in exocytosis, endocytosis or in the morphology or location of multiple markers for the endomembrane system, suggesting that neither RabX1 nor RabX2 has a major role in intracellular transport. However, it was apparent that RabX1 and RabX2 knockout cells displayed somewhat enhanced survival within flies. CONCLUSIONS/SIGNIFICANCE: RabX1 and RabX2, two members of the trypanosome Rab subfamily, were shown to have no major detectable role in intracellular transport, despite the localization of each gene product to highly specific endomembrane compartments. These data extend the functional scope of Rab proteins in trypanosomes to include non

  19. Fruit Flies Help Human Sleep Research

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues Fruit Flies Help Human Sleep Research Past Issues / Summer 2007 ... courtesy of NIGMS Neuroscientist Chiara Cirelli uses experimental fruit flies to study sleep. Although it may be tough ...

  20. Genome of the avirulent human-infective trypanosome--Trypanosoma rangeli.

    Directory of Open Access Journals (Sweden)

    Patrícia Hermes Stoco

    2014-09-01

    Full Text Available Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts.The T. rangeli haploid genome is ∼ 24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93% are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heat-shock proteins.Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets.

  1. Social motility in african trypanosomes.

    Directory of Open Access Journals (Sweden)

    Michael Oberholzer

    2010-01-01

    Full Text Available African trypanosomes are devastating human and animal pathogens that cause significant human mortality and limit economic development in sub-Saharan Africa. Studies of trypanosome biology generally consider these protozoan parasites as individual cells in suspension cultures or in animal models of infection. Here we report that the procyclic form of the African trypanosome Trypanosoma brucei engages in social behavior when cultivated on semisolid agarose surfaces. This behavior is characterized by trypanosomes assembling into multicellular communities that engage in polarized migrations across the agarose surface and cooperate to divert their movements in response to external signals. These cooperative movements are flagellum-mediated, since they do not occur in trypanin knockdown parasites that lack normal flagellum motility. We term this behavior social motility based on features shared with social motility and other types of surface-induced social behavior in bacteria. Social motility represents a novel and unexpected aspect of trypanosome biology and offers new paradigms for considering host-parasite interactions.

  2. The evolution of pathogenic trypanosomes

    Directory of Open Access Journals (Sweden)

    Jamie R. Stevens

    Full Text Available In the absence of a fossil record, the evolution of protozoa has until recently largely remained a matter for speculation. However, advances in molecular methods and phylogenetic analysis are now allowing interpretation of the "history written in the genes". This review focuses on recent progress in reconstruction of trypanosome phylogeny based on molecular data from ribosomal RNA, the miniexon and protein-coding genes. Sufficient data have now been gathered to demonstrate unequivocally that trypanosomes are monophyletic; the phylogenetic trees derived can serve as a framework to reinterpret the biology, taxonomy and present day distribution of trypanosome species, providing insights into the coevolution of trypanosomes with their vertebrate hosts and vectors. Different methods of dating the divergence of trypanosome lineages give rise to radically different evolutionary scenarios and these are reviewed. In particular, the use of one such biogeographically based approach provides new insights into the coevolution of the pathogens, Trypanosoma brucei and Trypanosoma cruzi, with their human hosts and the history of the diseases with which they are associated.

  3. Zoonotic trypanosomes in South East Asia: Attempts to control Trypanosoma lewisi using human and animal trypanocidal drugs.

    Science.gov (United States)

    Desquesnes, Marc; Yangtara, Sarawut; Kunphukhieo, Pawinee; Jittapalapong, Sathaporn; Herder, Stéphane

    2016-10-01

    Beside typical human trypanosomes responsible of sleeping sickness in Africa and Chagas disease in Latin America, there is a growing number of reported atypical human infections due to Trypanosoma evansi, a livestock parasite, or Trypanosoma lewisi, a rat parasite, especially in Asia. Drugs available for the treatment of T. brucei ssp. in humans are obviously of choice for the control of T. evansi because it is derived from T. brucei. However, concerning T. lewisi, there is an urgent need to determine the efficacy of trypanocidal drugs for the treatment in humans. In a recent study, pentamidine and fexinidazole were shown to have the best efficacy against one stock of T. lewisi in rats. In the present study suramin, pentamidine, eflornitine, nifurtimox, benznidazole and fexinidazole, were evaluated at low and high doses, in single day administration to normal rats experimentally infected with a stock of T. lewisi recently isolated in Thailand. Because none of these treatments was efficient, a trial was made with the most promising trypanocide identified in a previous study, fexinidazole 100mg/kg, in 5 daily administrations. Results observed were unclear. To confirm the efficacy of fexinidazole, a mixed infection protocol was set up in cyclophosphamide immunosuppressed rats. Animals were infected successively by T. lewisi and T. evansi, and received 10 daily PO administrations of 200mg/kg fexinidazole. Drastic effects were observed against T. evansi which was cleared from the rat's blood within 24 to 48h; however, the treatment did not affect T. lewisi which remained in high number in the blood until the end of the experiment. This mixed infection/treatment protocol clearly demonstrated the efficacy of fexinidazole against T. evansi and its inefficacy against T. lewisi. Since animal trypanocides were also recently shown to be inefficient, other protocols as well as other T. lewisi stocks should be investigated in further studies.

  4. Antigenic variation in trypanosomes: enhanced phenotypic variation in a eukaryotic parasite.

    Science.gov (United States)

    Barry, J D; McCulloch, R

    2001-01-01

    African trypanosomes are unicellular, eukaryotic parasites that live extracellularly in a wide range of mammals, including humans. They have a surface coat, composed of variant surface glycoprotein (VSG), which probably is essential and acts as a defence against general innate immunity and against acquired immunity directed at invariant surface antigens. In effect, the VSG is the only antigen that the host can target, and each trypanosome expresses only one VSG. To counter specific antibodies against the VSG, trypanosomes periodically undergo antigenic variation, the change to expression of another VSG. Antigenic variation belongs to the general survival strategy of enhanced phenotypic variation, where a subset of 'contingency' genes of viruses, bacteria and parasites hypermutate, allowing rapid adaptation to hostile or changing environments. A fundamental feature of antigenic variation is its link with the population dynamics of trypanosomes within the single host. Antigenic variants appear hierarchically within the mammalian host, with a mixture of order and randomness. The underlying mechanisms of this are not understood, although differential VSG gene activation may play a prominent part. Trypanosome antigenic variation has evolved a second arm in which the infective metacyclic population in the tsetse fly expresses a defined mixture of VSGs, although again each trypanosome expresses a single VSG. Differential VSG expression enhances transmission to new hosts, in the case of bloodstream trypanosomes by prolonging infection, and in the metacyclic population by generating diversity that may counter existing partial immunity in reservoir hosts. Antigenic variation employs a huge repertoire of VSG genes. Only one is expressed at a time in bloodstream trypanosomes, as a result of transcription being restricted to a set of about 20 bloodstream expression sites (BESs), which are at chromosome telomeres. Only one BES is active at a time, probably through

  5. Human and animal Trypanosomes in Cote d'Ivoire form a single breeding population.

    Directory of Open Access Journals (Sweden)

    Paul Capewell

    Full Text Available BACKGROUND: Trypanosoma brucei is the causative agent of African Sleeping Sickness in humans and contributes to the related veterinary disease, Nagana. T. brucei is segregated into three subspecies based on host specificity, geography and pathology. T. b. brucei is limited to animals (excluding some primates throughout sub-Saharan Africa and is non-infective to humans due to trypanolytic factors found in human serum. T. b. gambiense and T. b. rhodesiense are human infective sub-species. T. b. gambiense is the more prevalent human, causing over 97% of human cases. Study of T. b. gambiense is complicated in that there are two distinct groups delineated by genetics and phenotype. The relationships between the two groups and local T. b. brucei are unclear and may have a bearing on the evolution of the human infectivity traits. METHODOLOGY/PRINCIPAL FINDINGS: A collection of sympatric T. brucei isolates from Côte d'Ivoire, consisting of T. b. brucei and both groups of T. b. gambiense have previously been categorized by isoenzymes, RFLPs and Blood Incubation Infectivity Tests. These samples were further characterized using the group 1 specific marker, TgSGP, and seven microsatellites. The relationships between the T. b. brucei and T. b. gambiense isolates were determined using principal components analysis, neighbor-joining phylogenetics, STRUCTURE, FST, Hardy-Weinberg equilibrium and linkage disequilibrium. CONCLUSIONS/SIGNIFICANCE: Group 1 T. b. gambiense form a clonal genetic group, distinct from group 2 and T. b. brucei, whereas group 2 T. b. gambiense are genetically indistinguishable from local T. b. brucei. There is strong evidence for mating within and between group 2 T. b. gambiense and T. b. brucei. We found no evidence to support the hypothesis that group 2 T. b. gambiense are hybrids of group 1 and T. b. brucei, suggesting that human infectivity has evolved independently in groups 1 and 2 T. b. gambiense.

  6. The silicon trypanosome

    NARCIS (Netherlands)

    Bakker, Barbara M.; Krauth-Siegel, R. Luise; Clayton, Christine; Matthews, Keith; Girolami, Mark; Westerhoff, Hans V.; Michels, Paul A. M.; Breitling, Rainer; Barrett, Michael P.

    2010-01-01

    African trypanosomes have emerged as promising unicellular model organisms for the next generation of systems biology. They offer unique advantages, due to their relative simplicity, the availability of all standard genomics techniques and a long history of quantitative research. Reproducible cultiv

  7. Palpebral myiasis in a Danish traveler caused by the human bot-fly (Dermatobia hominis)

    DEFF Research Database (Denmark)

    Bangsgaard, Regitze; Holst, Bengt; Krogh, Erik

    2000-01-01

    ophthalmology, dermatobia hominis, human bot-fly, palpebral myiasis, parasite infection, myiasis......ophthalmology, dermatobia hominis, human bot-fly, palpebral myiasis, parasite infection, myiasis...

  8. Post eclosion age predicts the prevalence of midgut trypanosome infections in Glossina.

    Directory of Open Access Journals (Sweden)

    Deirdre P Walshe

    Full Text Available The teneral phenomenon, as observed in Glossina sp., refers to the increased susceptibility of the fly to trypanosome infection when the first bloodmeal taken is trypanosome-infected. In recent years, the term teneral has gradually become synonymous with unfed, and thus fails to consider the age of the newly emerged fly at the time the first bloodmeal is taken. Furthermore, conflicting evidence exists of the effect of the age of the teneral fly post eclosion when it is given the infected first bloodmeal in determining the infection prevalence. This study demonstrates that it is not the feeding history of the fly but rather the age (hours after eclosion of the fly from the puparium of the fly when it takes the first (infective bloodmeal that determines the level of fly susceptibility to trypanosome infection. We examine this phenomenon in male and female flies from two distinct tsetse clades (Glossina morsitans morsitans and Glossina palpalis palpalis infected with two salivarian trypanosome species, Trypanosoma (Trypanozoon brucei brucei and Trypanosoma (Nannomonas congolense using Fisher's exact test to examine differences in infection rates. Teneral tsetse aged less than 24 hours post-eclosion (h.p.e. are twice as susceptible to trypanosome infection as flies aged 48 h.p.e. This trend is conserved across sex, vector clade and parasite species. The life cycle stage of the parasite fed to the fly (mammalian versus insect form trypanosomes does not alter this age-related bias in infection. Reducing the numbers of parasites fed to 48 h.p.e., but not to 24 h.p.e. flies, increases teneral refractoriness. The importance of this phenomenon in disease biology in the field as well as the necessity of employing flies of consistent age in laboratory-based infection studies is discussed.

  9. Tsetse fly saliva: Could it be useful in fly infection when feeding in chronically aparasitemic mammalian hosts

    Directory of Open Access Journals (Sweden)

    E.O. Awuoche

    2012-09-01

    Full Text Available Sleeping sickness and nagana are two important diseases cuased by African trypanosomes in humans and animals respectively, in tropical african countries. A number of trypanosome species are implicated in these diseases, but it is the Trypanosoma brucei group that is responsible for the chronic form of sleeping sickness. During the course of this chronic infection the parasite shows a clear tropism for organs and tissues and only sporadically appears in the blood stream. Notwithstanding this feature, tsetse flies normally get infected from chronically infected apparasitemic hosts. For some pathogens like the microfilaria, it has already shown that the saliva of the vector, black fly saliva contribute to orient the pathogen to the site of the vector bite. Chemotaxis of tsetse saliva may perhaps stimulate movement of Trypanosoma brucei parasites from tissues to the bloodstream and via the vascular to the tsetse feeding site, and could explain the relatively high infection rate of tsetse flies feeding on chronically infected animals. This review paper looks into the possible role of trypanosome-vector saliva in ensuring parasite acquisition and its application in the tsetse – trypanosome interaction at the host skin interphase.

  10. Identification of a tsetse fly salivary protein with dual inhibitory action on human platelet aggregation.

    Directory of Open Access Journals (Sweden)

    Guy Caljon

    Full Text Available BACKGROUND: Tsetse flies (Glossina sp., the African trypanosome vectors, rely on anti-hemostatic compounds for efficient blood feeding. Despite their medical importance, very few salivary proteins have been characterized and functionally annotated. METHODOLOGY/PRINCIPAL FINDINGS: Here we report on the functional characterisation of a 5'nucleotidase-related (5'Nuc saliva protein of the tsetse fly Glossina morsitans morsitans. This protein is encoded by a 1668 bp cDNA corresponding at the genomic level with a single-copy 4 kb gene that is exclusively transcribed in the tsetse salivary gland tissue. The encoded 5'Nuc protein is a soluble 65 kDa glycosylated compound of tsetse saliva with a dual anti-hemostatic action that relies on its combined apyrase activity and fibrinogen receptor (GPIIb/IIIa antagonistic properties. Experimental evidence is based on the biochemical and functional characterization of recombinant protein and on the successful silencing of the 5'nuc translation in the salivary gland by RNA interference (RNAi. Refolding of a 5'Nuc/SUMO-fusion protein yielded an active apyrase enzyme with K(m and V(max values of 43+/-4 microM and 684+/-49 nmol Pi/min xmg for ATPase and 49+/-11 microM and 177+/-37 nmol Pi/min xmg for the ADPase activity. In addition, recombinant 5'Nuc was found to bind to GPIIb/IIIa with an apparent K(D of 92+/-25 nM. Consistent with these features, 5'Nuc potently inhibited ADP-induced thrombocyte aggregation and even caused disaggregation of ADP-triggered human platelets. The importance of 5'Nuc for the tsetse fly hematophagy was further illustrated by specific RNAi that reduced the anti-thrombotic activities in saliva by approximately 50% resulting in a disturbed blood feeding process. CONCLUSIONS/SIGNIFICANCE: These data show that this 5'nucleotidase-related apyrase exhibits GPIIb/IIIa antagonistic properties and represents a key thromboregulatory compound of tsetse fly saliva.

  11. Trypanosomes of Australian Mammals: Knowledge Gaps Regarding Transmission and Biosecurity.

    Science.gov (United States)

    Thompson, Craig K; Thompson, R C Andrew

    2015-11-01

    Trypanosomes infect humans, domestic animals, and wildlife, and are transmitted by haematophagous invertebrate vectors. Eight native trypanosome species have been described from Australian indigenous mammals, along with other unnamed isolates and genotypes. Associated difficulties relating to the confirmation of cyclical and mechanical vector candidates has hindered vector identification in Australia, with no successful experimental transmission documented for any of these native trypanosomes to indigenous mammals. We discuss pending biosecurity issues, with significant importance placed on the close phylogenetic and phenotypic relationship shared between Trypanosoma cruzi and some Australian trypanosomes. With such a dearth of information, we highlight the importance of keeping an open mind, which considers all possibilities during future investigations of vectors and their associated biosecurity issues in Australia.

  12. Tsetse fly microbiota: form and function

    Directory of Open Access Journals (Sweden)

    Jingwen eWang

    2013-10-01

    Full Text Available Tsetse flies are the primary vectors of African trypanosomes, which cause Human and Animal African trypanosomiasis in 36 countries in sub-Saharan Africa. These flies have also established symbiotic associations with bacterial and viral microorganisms. Laboratory-reared tsetse flies harbor up to four vertically transmitted organisms - obligate Wigglesworthia, commensal Sodalis, parasitic Wolbachia and Salivary Gland Hypertrophy Virus (SGHV. Field-captured tsetse can harbor these symbionts as well as environmentally acquired commensal bacteria. This microbial community influences several aspects of tsetse’s physiology, including nutrition, fecundity and vector competence. This review provides a detailed description of tsetse’s microbiome, and describes the physiology underlying host-microbe, and microbe-microbe, interactions that occur in this fly.

  13. Trypanosomes of some Fennoscandian birds

    Directory of Open Access Journals (Sweden)

    Gordon F. Bennett

    1994-12-01

    Full Text Available Linear measurements and derived indices of trypanosomes from species of Fennoscandian birds were compared to those reported form Trypanosoma avium, T. everetti, T. ontarioensis and T. paddae. The trypanosomes encountered in the Fennoscandian birds were identified as T. avium from Tengmalm's owl Aegolius funereus and the pied flycatcher Ficedula hypoleuca, T. everetti from the great tit Parus major and collared flycatcher F. albicollis and T. ontarioensis from the collared flycatcher; T. paddae was not seen.

  14. A Receptor’s Tale: An Eon in the Life of a Trypanosome Receptor

    Science.gov (United States)

    Lane-Serff, Harriet; MacGregor, Paula; Carrington, Mark

    2017-01-01

    African trypanosomes have complex life cycles comprising at least ten developmental forms, variously adapted to different niches in their tsetse fly vector and their mammalian hosts. Unlike many other protozoan pathogens, they are always extracellular and have evolved intricate surface coats that allow them to obtain nutrients while also protecting them from the immune defenses of either insects or mammals. The acquisition of macromolecular nutrients requires receptors that function within the context of these surface coats. The best understood of these is the haptoglobin–hemoglobin receptor (HpHbR) of Trypanosoma brucei, which is used by the mammalian bloodstream form of the parasite, allowing heme acquisition. However, in some primates it also provides an uptake route for trypanolytic factor-1, a mediator of innate immunity against trypanosome infection. Recent studies have shown that during the evolution of African trypanosome species the receptor has diversified in function from a hemoglobin receptor predominantly expressed in the tsetse fly to a haptoglobin–hemoglobin receptor predominantly expressed in the mammalian bloodstream. Structural and functional studies of homologous receptors from different trypanosome species have allowed us to propose an evolutionary history for how one receptor has adapted to different roles in different trypanosome species. They also highlight the challenges that a receptor faces in operating on the complex trypanosome surface and show how these challenges can be met. PMID:28125726

  15. Assembling the components of the quorum sensing pathway in African trypanosomes.

    Science.gov (United States)

    Mony, Binny M; Matthews, Keith R

    2015-04-01

    African trypanosomes, parasites that cause human sleeping sickness, undergo a density-dependent differentiation in the bloodstream of their mammalian hosts. This process is driven by a released parasite-derived factor that causes parasites to accumulate in G1 and become quiescent. This is accompanied by morphological transformation to 'stumpy' forms that are adapted to survival and further development when taken up in the blood meal of tsetse flies, the vector for trypanosomiasis. Although the soluble signal driving differentiation to stumpy forms is unidentified, a recent genome-wide RNAi screen identified many of the intracellular signalling and effector molecules required for the response to this signal. These resemble components of nutritional starvation and quiescence pathways in other eukaryotes, suggesting that parasite development shares similarities with the adaptive quiescence of organisms such as yeasts and Dictyostelium in response to nutritional starvation and stress. Here, the trypanosome signalling pathway is discussed in the context of these conserved pathways and the possible contributions of opposing 'slender retainer' and 'stumpy inducer' arms described. As evolutionarily highly divergent eukaryotes, the organisation and conservation of this developmental pathway can provide insight into the developmental cycle of other protozoan parasites, as well as the adaptive and programmed developmental responses of all eukaryotic cells.

  16. Methods to determine the transcriptomes of trypanosomes in mixtures with mammalian cells: the effects of parasite purification and selective cDNA amplification.

    Directory of Open Access Journals (Sweden)

    Julius Mulindwa

    2014-04-01

    Full Text Available Patterns of gene expression in cultured Trypanosoma brucei bloodstream and procyclic forms have been extensively characterized, and some comparisons have been made with trypanosomes grown to high parasitaemias in laboratory rodents. We do not know, however, to what extent these transcriptomes resemble those in infected Tsetse flies - or in humans or cattle, where parasitaemias are substantially lower. For clinical and field samples it is difficult to characterize parasite gene expression because of the large excess of host cell RNA. We have here examined two potential solutions to this problem for bloodstream form trypanosomes, assaying transcriptomes by high throughput cDNA sequencing (RNASeq. We first purified the parasites from blood of infected rats. We found that a red blood cell lysis procedure affected the transcriptome substantially more than purification using a DEAE cellulose column, but that too introduced significant distortions and variability. As an alternative, we specifically amplified parasite sequences from a mixture containing a 1000-fold excess of human RNA. We first purified polyadenylated RNA, then made trypanosome-specific cDNA by priming with a spliced leader primer. Finally, the cDNA was amplified using nested primers. The amplification procedure was able to produce samples in which 20% of sequence reads mapped to the trypanosome genome. Synthesis of the second cDNA strand with a spliced leader primer, followed by amplification, is sufficiently reproducible to allow comparison of different samples so long as they are all treated in the same way. However, SL priming distorted the abundances of the cDNA products and definitely cannot be used, by itself, to measure absolute mRNA levels. The amplification method might be suitable for clinical samples with low parasitaemias, and could also be adapted for other Kinetoplastids and to samples from infected vectors.

  17. The diurnal activity, movement and trypanosome infection rates of Glossina fuscipes fuscipes (Diptera: Glossinidae)in Buvuma Island, Lake Victoria, Uganda

    Institute of Scientific and Technical Information of China (English)

    LONJINO M. OGWAL; ANDREW KALYEBI; JOHN B. KADDU

    2007-01-01

    The diurnal activity patterns, trypanosome infection rates and movement of Glossina fuscipes fuscipes(Diptera: Glossinidae) were investigated in Buvuma Island, Lake Victoria, Uganda. Hourly trapping of tsetse flies was undertaken to determine their activity rhythm while a capture-mark-release-recapture method was conducted to assess the movement and dispersal of tsetse flies between lakeshore, hinterland and further inland sites along a transected area. Dissection of tsetse flies was also undertaken to determine the trypanosome infection rates in salivary glands, proboscis and mid-gut. Results indicated a bimodal diurnal activity profile for G. f. fuscipes on the Island, both on the lakeshore and in the hinterland.Movement and dispersal of G. f. fuscipes tsetse flies occurred between lakeshore, hinterland and further inland sites with a greater tendency of flies to move to the lakeshore. Trypanosome infection rates of 4.32% for Trypasoma vivax and 1.15% for T. congolense were found in G. f. fuscipes.

  18. Counterflow Dielectrophoresis for Trypanosome Enrichment and Detection in Blood

    Science.gov (United States)

    Menachery, Anoop; Kremer, Clemens; Wong, Pui E.; Carlsson, Allan; Neale, Steven L.; Barrett, Michael P.; Cooper, Jonathan M.

    2012-10-01

    Human African trypanosomiasis or sleeping sickness is a deadly disease endemic in sub-Saharan Africa, caused by single-celled protozoan parasites. Although it has been targeted for elimination by 2020, this will only be realized if diagnosis can be improved to enable identification and treatment of afflicted patients. Existing techniques of detection are restricted by their limited field-applicability, sensitivity and capacity for automation. Microfluidic-based technologies offer the potential for highly sensitive automated devices that could achieve detection at the lowest levels of parasitemia and consequently help in the elimination programme. In this work we implement an electrokinetic technique for the separation of trypanosomes from both mouse and human blood. This technique utilises differences in polarisability between the blood cells and trypanosomes to achieve separation through opposed bi-directional movement (cell counterflow). We combine this enrichment technique with an automated image analysis detection algorithm, negating the need for a human operator.

  19. Early invasion of brain parenchyma by African trypanosomes.

    Directory of Open Access Journals (Sweden)

    Ute Frevert

    Full Text Available Human African trypanosomiasis or sleeping sickness is a vector-borne parasitic disease that has a major impact on human health and welfare in sub-Saharan countries. Based mostly on data from animal models, it is currently thought that trypanosome entry into the brain occurs by initial infection of the choroid plexus and the circumventricular organs followed days to weeks later by entry into the brain parenchyma. However, Trypanosoma brucei bloodstream forms rapidly cross human brain microvascular endothelial cells in vitro and appear to be able to enter the murine brain without inflicting cerebral injury. Using a murine model and intravital brain imaging, we show that bloodstream forms of T. b. brucei and T. b. rhodesiense enter the brain parenchyma within hours, before a significant level of microvascular inflammation is detectable. Extravascular bloodstream forms were viable as indicated by motility and cell division, and remained detectable for at least 3 days post infection suggesting the potential for parasite survival in the brain parenchyma. Vascular inflammation, as reflected by leukocyte recruitment and emigration from cortical microvessels, became apparent only with increasing parasitemia at later stages of the infection, but was not associated with neurological signs. Extravascular trypanosomes were predominantly associated with postcapillary venules suggesting that early brain infection occurs by parasite passage across the neuroimmunological blood brain barrier. Thus, trypanosomes can invade the murine brain parenchyma during the early stages of the disease before meningoencephalitis is fully established. Whether individual trypanosomes can act alone or require the interaction from a quorum of parasites remains to be shown. The significance of these findings for disease development is now testable.

  20. Survey of the Synanthropic Flies Associated with Human Habitations in Ubon Ratchathani Province of Northeast Thailand

    Directory of Open Access Journals (Sweden)

    Tarinee Chaiwong

    2012-01-01

    Full Text Available Synanthropic fly surveys were performed to determine the species composition and abundance in Ubon Ratchathani province in Northeast Thailand. Adult fly collections were conducted in various human habitations from two districts—Muang Ubon Ratchathani and Warinchamrap, at fresh-food markets, garbage piles, restaurants, school cafeterias, and rice paddy fields. Customized reconstructable funnel fly traps baited with 250 g of 1-day tainted beef were used for fly collections from September 2010–February 2011. A total of 3,262 flies were captured, primarily consisting of three families including: Calliphoridae (6 species, Muscidae (3 species, and Sarcophagidae (11 species. The blow fly, Chrysomya megacephala, and the house fly, Musca domestica, were the dominant species collected from both districts at all collection sites. C. megacephala was predominant in paddy fields, restaurants and garbage piles, while M. domestica was numerically dominant in fresh-food markets and school cafeterias. The current survey identified various species of synanthropic flies with close associations to humans and with the ability to transmit human pathogens in Ubon Ratchathani province; providing crucial information that may be used for developing control and sanitation management plans in this particular area.

  1. A QMRA for the Transmission of ESBL-Producing Escherichia coli and Campylobacter from Poultry Farms to Humans Through Flies.

    Science.gov (United States)

    Evers, Eric G; Blaak, Hetty; Hamidjaja, Raditijo A; de Jonge, Rob; Schets, Franciska M

    2016-02-01

    The public health significance of transmission of ESBL-producing Escherichia coli and Campylobacter from poultry farms to humans through flies was investigated using a worst-case risk model. Human exposure was modeled by the fraction of contaminated flies, the number of specific bacteria per fly, the number of flies leaving the poultry farm, and the number of positive poultry houses in the Netherlands. Simplified risk calculations for transmission through consumption of chicken fillet were used for comparison, in terms of the number of human exposures, the total human exposure, and, for Campylobacter only, the number of human cases of illness. Comparing estimates of the worst-case risk of transmission through flies with estimates of the real risk of chicken fillet consumption, the number of human exposures to ESBL-producing E. coli was higher for chicken fillet as compared with flies, but the total level of exposure was higher for flies. For Campylobacter, risk values were nearly consistently higher for transmission through flies than for chicken fillet consumption. This indicates that the public health risk of transmission of both ESBL-producing E. coli and Campylobacter to humans through flies might be of importance. It justifies further modeling of transmission through flies for which additional data (fly emigration, human exposure) are required. Similar analyses of other environmental transmission routes from poultry farms are suggested to precede further investigations into flies.

  2. Indoors forensic entomology: colonization of human remains in closed environments by specific species of sarcosaprophagous flies.

    Science.gov (United States)

    Pohjoismäki, Jaakko L O; Karhunen, Pekka J; Goebeler, Sirkka; Saukko, Pekka; Sääksjärvi, Ilari E

    2010-06-15

    Fly species that are commonly recovered on human corpses concealed in houses or other dwellings are often dependent on human created environments and might have special features in their biology that allow them to colonize indoor cadavers. In this study we describe nine typical cases involving forensically relevant flies on human remains found indoors in southern Finland. Eggs, larvae and puparia were reared to adult stage and determined to species. Of the five species found the most common were Lucilia sericata Meigen, Calliphora vicina Robineau-Desvoidy and Protophormia terraenovae Robineau-Desvoidy. The flesh fly Sarcophaga caerulescens Zetterstedt is reported for the first time to colonize human cadavers inside houses and a COI gene sequence based DNA barcode is provided for it to help facilitate identification in the future. Fly biology, colonization speed and the significance of indoors forensic entomological evidence are discussed.

  3. CRYSTAL-STRUCTURE OF RECOMBINANT HUMAN TRIOSEPHOSPHATE ISOMERASE AT 2.8 ANGSTROM RESOLUTION - TRIOSEPHOSPHATE ISOMERASE-RELATED HUMAN GENETIC-DISORDERS AND COMPARISON WITH THE TRYPANOSOMAL ENZYME

    NARCIS (Netherlands)

    MANDE, SC; MAINFROID, [No Value; KALK, KH; GORAJ, K; MARTIAL, JA; HOL, WGJ

    1994-01-01

    The crystal structure of recombinant human triosephosphate isomerase (hTIM) has been determined complexed with the transition-state analogue 2-phosphoglycolate at a resolution of 2.8 Angstrom. After refinement, the R-factor is 16.7% with good geometry. The asymmetric unit contains 1 complete dimer o

  4. African Trypanosomes Undermine Humoral Responses and Vaccine Development: Link with Inflammatory Responses?

    Directory of Open Access Journals (Sweden)

    Benoit Stijlemans

    2017-05-01

    Full Text Available African trypanosomosis is a debilitating disease of great medical and socioeconomical importance. It is caused by strictly extracellular protozoan parasites capable of infecting all vertebrate classes including human, livestock, and game animals. To survive within their mammalian host, trypanosomes have evolved efficient immune escape mechanisms and manipulate the entire host immune response, including the humoral response. This report provides an overview of how trypanosomes initially trigger and subsequently undermine the development of an effective host antibody response. Indeed, results available to date obtained in both natural and experimental infection models show that trypanosomes impair homeostatic B-cell lymphopoiesis, B-cell maturation and survival and B-cell memory development. Data on B-cell dysfunctioning in correlation with parasite virulence and trypanosome-mediated inflammation will be discussed, as well as the impact of trypanosomosis on heterologous vaccine efficacy and diagnosis. Therefore, new strategies aiming at enhancing vaccination efficacy could benefit from a combination of (i early parasite diagnosis, (ii anti-trypanosome (drugs treatment, and (iii anti-inflammatory treatment that collectively might allow B-cell recovery and improve vaccination.

  5. Attentional switching in humans and flies: rivalry in large and miniature brains

    Directory of Open Access Journals (Sweden)

    Steven Mark Miller

    2012-01-01

    Full Text Available Human perception, and consequently behaviour, is driven by attention dynamics. In the special case of rivalry, where attention alternates between competing percepts, such dynamics can be measured and their determinants investigated. A recent study in the fruit fly, Drosophila melanogaster, now shows that the origins of attentional rivalry may be quite ancient. Furthermore, individual variation exists in the rate of attentional rivalry in both humans and flies, and in humans this is under substantial genetic influence. In the pathophysiological realm, slowing of rivalry rate is associated with the heritable psychiatric condition, bipolar disorder. Fly rivalry may therefore prove a powerful model to examine genetic and molecular influences on rivalry rate, and may even shed light on human cognitive and behavioural dysfunction.

  6. Bromodomain Proteins Contribute to Maintenance of Bloodstream Form Stage Identity in the African Trypanosome.

    Directory of Open Access Journals (Sweden)

    Danae Schulz

    2015-12-01

    Full Text Available Trypanosoma brucei, the causative agent of African sleeping sickness, is transmitted to its mammalian host by the tsetse. In the fly, the parasite's surface is covered with invariant procyclin, while in the mammal it resides extracellularly in its bloodstream form (BF and is densely covered with highly immunogenic Variant Surface Glycoprotein (VSG. In the BF, the parasite varies this highly immunogenic surface VSG using a repertoire of ~2500 distinct VSG genes. Recent reports in mammalian systems point to a role for histone acetyl-lysine recognizing bromodomain proteins in the maintenance of stem cell fate, leading us to hypothesize that bromodomain proteins may maintain the BF cell fate in trypanosomes. Using small-molecule inhibitors and genetic mutants for individual bromodomain proteins, we performed RNA-seq experiments that revealed changes in the transcriptome similar to those seen in cells differentiating from the BF to the insect stage. This was recapitulated at the protein level by the appearance of insect-stage proteins on the cell surface. Furthermore, bromodomain inhibition disrupts two major BF-specific immune evasion mechanisms that trypanosomes harness to evade mammalian host antibody responses. First, monoallelic expression of the antigenically varied VSG is disrupted. Second, rapid internalization of antibodies bound to VSG on the surface of the trypanosome is blocked. Thus, our studies reveal a role for trypanosome bromodomain proteins in maintaining bloodstream stage identity and immune evasion. Importantly, bromodomain inhibition leads to a decrease in virulence in a mouse model of infection, establishing these proteins as potential therapeutic drug targets for trypanosomiasis. Our 1.25Å resolution crystal structure of a trypanosome bromodomain in complex with I-BET151 reveals a novel binding mode of the inhibitor, which serves as a promising starting point for rational drug design.

  7. The Silicon Trypanosome : A Test Case of Iterative Model Extension in Systems Biology

    NARCIS (Netherlands)

    Achcar, Fiona; Fadda, Abeer; Haanstra, Jurgen R.; Kerkhoven, Eduard J.; Kim, Dong-Hyun; Leroux, Alejandro E.; Papamarkou, Theodore; Rojas, Federico; Bakker, Barbara M.; Barrett, Michael P.; Clayton, Christine; Girolami, Mark; Krauth-Siegel, R. Luise; Matthews, Keith R.; Breitling, Rainer; Poole, RK

    2014-01-01

    The African trypanosome, Ttypanosoma brucei, is a unicellular parasite causing African Trypanosomiasis (sleeping sickness in humans and nagana in animals). Due to some of its unique properties, it has emerged as a popular model organism in systems biology. A predictive quantitative model of glycolys

  8. Evolutionary history of trypanosomes from South American caiman (Caiman yacare) and African crocodiles inferred by phylogenetic analyses using SSU rDNA and gGAPDH genes.

    Science.gov (United States)

    Viola, L B; Almeida, R S; Ferreira, R C; Campaner, M; Takata, C S A; Rodrigues, A C; Paiva, F; Camargo, E P; Teixeira, M M G

    2009-01-01

    In this study, using a combined data set of SSU rDNA and gGAPDH gene sequences, we provide phylogenetic evidence that supports clustering of crocodilian trypanosomes from the Brazilian Caiman yacare (Alligatoridae) and Trypanosoma grayi, a species that circulates between African crocodiles (Crocodilydae) and tsetse flies. In a survey of trypanosomes in Caiman yacare from the Brazilian Pantanal, the prevalence of trypanosome infection was 35% as determined by microhaematocrit and haemoculture, and 9 cultures were obtained. The morphology of trypomastigotes from caiman blood and tissue imprints was compared with those described for other crocodilian trypanosomes. Differences in morphology and growth behaviour of caiman trypanosomes were corroborated by molecular polymorphism that revealed 2 genotypes. Eight isolates were ascribed to genotype Cay01 and 1 to genotype Cay02. Phylogenetic inferences based on concatenated SSU rDNA and gGAPDH sequences showed that caiman isolates are closely related to T. grayi, constituting a well-supported monophyletic assemblage (clade T. grayi). Divergence time estimates based on clade composition, and biogeographical and geological events were used to discuss the relationships between the evolutionary histories of crocodilian trypanosomes and their hosts.

  9. Human intestinal parasites in non-biting synanthropic flies in Ogun State, Nigeria.

    Science.gov (United States)

    Adenusi, Adedotun Adesegun; Adewoga, Thomas O Sunday

    2013-01-01

    Filth-feeding and breeding, non-biting synanthropic flies have been incriminated in the dissemination of human enteropathogens in the environment. This study determined the species of non-biting synanthropic flies associated with four filthy sites in Ilishan, Ogun State, southwest Nigeria, and assessed their potentials for mechanical transmission of human intestinal parasites. 7190 flies identified as Musca domestica (33.94%), Chrysomya megacephala (26.01%), Musca sorbens (23.23%), Lucilia cuprina (8.76%), Calliphora vicina (4.59%), Sarcophaga sp. (2.78%) and Fannia scalaris (0.70%) were examined for human intestinal parasites by the formol-ether concentration and modified Ziehl-Neelsen techniques. Eggs of the following parasites: Ascaris lumbricoides (34.08%), Trichuris trichiura (25.87%), hookworms (20.45%), Taenia sp. (2.36%), Hymenolepis nana (1.11%), Enterobius vermicularis (0.56%), Strongyloides stercoralis (larvae; 3.89%) and cysts of Entamoeba histolytica/dispar (27.26%), Entamoeba coli (22.67%), Giardia lamblia (3.34%) and Cryptosporidium sp. (1.81%) were isolated from the body surfaces and or gut contents of 75.24% of 719 pooled fly batches. The helminths A. lumbricoides and T. trichiura and the protozoans, E. histolytica/dispar and E. coli were the dominant parasites detected, both on body surfaces and in the gut contents of flies. C. megacephala was the highest carrier of parasites (diversity and number). More parasites were isolated from the gut than from body surfaces (P parasites than those from abattoir, garbage or open-air market. Synanthropic fly species identified in this study can be of potential epidemiological importance as mechanical transmitters of human intestinal parasites acquired naturally from filth and carried on their body surfaces and or in the gut, because of their vagility and feeding mechanisms.

  10. Tsetse Flies (Glossina) as Vectors of Human African Trypanosomiasis: A Review.

    Science.gov (United States)

    Wamwiri, Florence Njeri; Changasi, Robert Emojong

    2016-01-01

    Human African Trypanosomiasis (HAT) transmitted by the tsetse fly continues to be a public health issue, despite more than a century of research. There are two types of the disease, the chronic gambiense and the acute rhodesiense-HAT. Fly abundance and distribution have been affected by changes in land-use patterns and climate. However, disease transmission still continues. Here, we review some aspects of HAT ecoepidemiology in the context of altered infestation patterns and maintenance of the transmission cycle as well as emerging options in disease and vector control.

  11. Tsetse Flies (Glossina as Vectors of Human African Trypanosomiasis: A Review

    Directory of Open Access Journals (Sweden)

    Florence Njeri Wamwiri

    2016-01-01

    Full Text Available Human African Trypanosomiasis (HAT transmitted by the tsetse fly continues to be a public health issue, despite more than a century of research. There are two types of the disease, the chronic gambiense and the acute rhodesiense-HAT. Fly abundance and distribution have been affected by changes in land-use patterns and climate. However, disease transmission still continues. Here, we review some aspects of HAT ecoepidemiology in the context of altered infestation patterns and maintenance of the transmission cycle as well as emerging options in disease and vector control.

  12. Human Disease Models in Drosophila melanogaster and the Role of the Fly in Therapeutic Drug Discovery

    Science.gov (United States)

    Pandey, Udai Bhan

    2011-01-01

    The common fruit fly, Drosophila melanogaster, is a well studied and highly tractable genetic model organism for understanding molecular mechanisms of human diseases. Many basic biological, physiological, and neurological properties are conserved between mammals and D. melanogaster, and nearly 75% of human disease-causing genes are believed to have a functional homolog in the fly. In the discovery process for therapeutics, traditional approaches employ high-throughput screening for small molecules that is based primarily on in vitro cell culture, enzymatic assays, or receptor binding assays. The majority of positive hits identified through these types of in vitro screens, unfortunately, are found to be ineffective and/or toxic in subsequent validation experiments in whole-animal models. New tools and platforms are needed in the discovery arena to overcome these limitations. The incorporation of D. melanogaster into the therapeutic discovery process holds tremendous promise for an enhanced rate of discovery of higher quality leads. D. melanogaster models of human diseases provide several unique features such as powerful genetics, highly conserved disease pathways, and very low comparative costs. The fly can effectively be used for low- to high-throughput drug screens as well as in target discovery. Here, we review the basic biology of the fly and discuss models of human diseases and opportunities for therapeutic discovery for central nervous system disorders, inflammatory disorders, cardiovascular disease, cancer, and diabetes. We also provide information and resources for those interested in pursuing fly models of human disease, as well as those interested in using D. melanogaster in the drug discovery process. PMID:21415126

  13. Phlebotomine sand fly-borne pathogens in the Mediterranean Basin: Human leishmaniasis and phlebovirus infections.

    Science.gov (United States)

    Moriconi, Martina; Rugna, Gianluca; Calzolari, Mattia; Bellini, Romeo; Albieri, Alessandro; Angelini, Paola; Cagarelli, Roberto; Landini, Maria P; Charrel, Remi N; Varani, Stefania

    2017-08-01

    Pathogens transmitted to humans by phlebotomine sand flies are neglected, as they cause infectious diseases that are not on the priority list of national and international public health systems. However, the infections caused by protozoa of the Leishmania genus and viruses belonging to the Phlebovirus genus (family Phenuiviridae)-the most significant group of viruses transmitted by sand flies-have a relevant role for human pathology. These infections are emerging in the Mediterranean region and will likely spread in forthcoming decades, posing a complex threat to human health. Four species and 2 hybrid strains of Leishmania are pathogenic for humans in the Mediterranean Basin, with an estimated annual incidence of 239,500-393,600 cases of cutaneous leishmaniasis and 1,200-2,000 cases of visceral leishmaniasis. Among the phleboviruses, Toscana virus can cause neuroinvasive infections, while other phleboviruses are responsible for a typical "3-day fever"; the actual incidence of Phlebovirus infections in the Mediterranean area is unknown, although at least 250 million people are exposed. Here, we reviewed the current literature on epidemiology of sand fly-borne infections in the Mediterranean Basin, with a focus on humans. Our analysis indicates the need for increased public health activities directed to determine the disease burden of these infections as well as to improve their surveillance. Among the emerging challenges concerning sand fly-borne pathogens, the relationships between sand fly-borne protozoa and viruses should be considered in future studies, including epidemiological links between Leishmania and phleboviruses as well as the conditional capacity for these pathogens to be involved in interactions that may evolve towards increased virulence.

  14. Excreted/Secreted Proteins from Trypanosome Procyclic Strains

    Directory of Open Access Journals (Sweden)

    Celestine Michelle Atyame Nten

    2010-01-01

    Full Text Available Trypanosoma secretome was shown to be involved in parasite virulence and is suspected of interfering in parasite life-cycle steps such as establishment in the Glossina midgut, metacyclogenesis. Therefore, we attempted to identify the proteins secreted by procyclic strains of T. brucei gambiense and T. brucei brucei, responsible for human and animal trypanosomiasis, respectively. Using mass spectrometry, 427 and 483 nonredundant proteins were characterized in T. brucei brucei and T. brucei gambiense secretomes, respectively; 35% and 42% of the corresponding secretome proteins were specifically secreted by T. brucei brucei and T. brucei gambiense, respectively, while 279 proteins were common to both subspecies. The proteins were assigned to 12 functional classes. Special attention was paid to the most abundant proteases (14 families because of their potential implication in the infection process and nutrient supply. The presence of proteins usually secreted via an exosome pathway suggests that this type of process is involved in trypanosome ESP secretion. The overall results provide leads for further research to develop novel tools for blocking trypanosome transmission.

  15. The trypanosome Pumilio domain protein PUF5.

    Directory of Open Access Journals (Sweden)

    Bhaskar Anand Jha

    Full Text Available PUF proteins are a conserved family of RNA binding proteins found in all eukaryotes examined so far. This study focussed on PUF5, one of 11 PUF family members encoded in the Trypanosoma brucei genome. Native PUF5 is present at less than 50000 molecules per cell in both bloodstream and procyclic form trypanosomes. C-terminally myc-tagged PUF5 was mainly found in the cytoplasm and could be cross-linked to RNA. PUF5 knockdown by RNA interference had no effect on the growth of bloodstream forms. Procyclic forms lacking PUF5 grew normally, but expression of PUF5 bearing a 21 kDa tandem affinity purification tag inhibited growth. Knockdown of PUF5 did not have any effect on the ability of trypanosomes to differentiate from the mammalian to the insect form of the parasite.

  16. Aquaglyceroporin 2 controls susceptibility to melarsoprol and pentamidine in African trypanosomes.

    Science.gov (United States)

    Baker, Nicola; Glover, Lucy; Munday, Jane C; Aguinaga Andrés, David; Barrett, Michael P; de Koning, Harry P; Horn, David

    2012-07-03

    African trypanosomes cause sleeping sickness in humans, a disease that is typically fatal without chemotherapy. Unfortunately, drug resistance is common and melarsoprol-resistant trypanosomes often display cross-resistance to pentamidine. Although melarsoprol/pentamidine cross-resistance (MPXR) has been an area of intense interest for several decades, our understanding of the underlying mechanisms remains incomplete. Recently, a locus encoding two closely related aquaglyceroporins, AQP2 and AQP3, was linked to MPXR in a high-throughput loss-of-function screen. Here, we show that AQP2 has an unconventional "selectivity filter." AQP2-specific gene knockout generated MPXR trypanosomes but did not affect resistance to a lipophilic arsenical, whereas recombinant AQP2 reversed MPXR in cells lacking native AQP2 and AQP3. AQP2 was also shown to be disrupted in a laboratory-selected MPXR strain. Both AQP2 and AQP3 gained access to the surface plasma membrane in insect life-cycle-stage trypanosomes but, remarkably, AQP2 was specifically restricted to the flagellar pocket in the bloodstream stage. We conclude that the unconventional aquaglyceroporin, AQP2, renders cells sensitive to both melarsoprol and pentamidine and that loss of AQP2 function could explain cases of innate and acquired MPXR.

  17. Affinity is an important determinant of the anti-trypanosome activity of nanobodies.

    Directory of Open Access Journals (Sweden)

    Guy Caljon

    Full Text Available BACKGROUND: The discovery of Nanobodies (Nbs with a direct toxic activity against African trypanosomes is a recent advancement towards a new strategy against these extracellular parasites. The anti-trypanosomal activity relies on perturbing the highly active recycling of the Variant-specific Surface Glycoprotein (VSG that occurs in the parasite's flagellar pocket. METHODOLOGY/PRINCIPAL FINDINGS: Here we expand the existing panel of Nbs with anti-Trypanosoma brucei potential and identify four categories based on their epitope specificity. We modified the binding properties of previously identified Nanobodies Nb_An05 and Nb_An33 by site-directed mutagenesis in the paratope and found this to strongly affect trypanotoxicity despite retention of antigen-targeting properties. Affinity measurements for all identified anti-trypanosomal Nbs reveal a strong correlation between trypanotoxicity and affinity (K(D, suggesting that it is a crucial determinant for this activity. Half maximal effective (50% affinity of 57 nM was calculated from the non-linear dose-response curves. In line with these observations, Nb humanizing mutations only preserved the trypanotoxic activity if the K(D remained unaffected. CONCLUSIONS/SIGNIFICANCE: This study reveals that the binding properties of Nanobodies need to be compatible with achieving an occupancy of >95% saturation of the parasite surface VSG in order to exert an anti-trypanosomal activity. As such, Nb-based approaches directed against the VSG target would require binding to an accessible, conserved epitope with high affinity.

  18. Diversity of bats trypanosomes in hydroeletric area of Belo Monte in Brazilian Amazonia.

    Science.gov (United States)

    da Costa, Andréa P; Nunes, Pablo Henrique; Leite, Beatriz Helena Santos; Ferreira, Juliana Isabel G da S; Tonhosolo, Renata; da Rosa, Adriana Ruckert; da Rocha, Patricio Adriano; Aires, Caroline Cotrim; Gennari, Solange Maria; Marcili, Arlei

    2016-12-01

    The Trypanosoma comprises flagellates able to infect many mammalian species and is transmitted by several groups of invertebrates. The order Chiroptera can be infected by the subgenera Herpetosoma, Schizotrypanum, Megatrypanum and Trypanozoon. In this study, we described the diversity of bats trypanosomes, inferring the phylogenetic relationships among the trypanosomes from bats caught Belo Monte Hydroeletric area (Brazilian Amazonia). Trypanosomes from bats were isolated by haemoculture, and the molecular phylogeny based on small subunit rDNA (SSU rDNA) and glycosomal-3-phosphate dehydrogenase (gGAPDH) gene sequences. Morphological characterization included light and scanning electron microscopy. A total of 157 bats were caught in the area belonging 6 Families (Emballonuridae, Furipteridae, Mormoopidae, Natalidae, Phyllostomidae and Vespertilionidae) and 34 species. The bat trypanosome prevalence, as evaluated through haemoculture, was 5,7%. Phylogenetic trees grouped the isolates in T. cruzi branch (TCI and TCbat lineage), T. cruzi marinkellei and Trypanosoma wauwau from Pteronotus parnellii. This is the first isolate from T. wauwau in Para state. The occurrence of T. cruzi in the ​​ Belo Monte Hydroeletric area (UHE Belo Monte) in Amazon/Brazil attentive to the risk of migration human population required for the works of the dam and new cities that grow in the vicinity of these businesses, but it is a zoonosis already known to the Amazon region, and the presence of unclassified Trypanosoma species, attend to the large parasitic biodiversity still unknown.

  19. Phenotypic characteristics and trypanosome prevalence of Mursi cattle breed in the Bodi and Mursi districts of South Omo Zone, southwest Ethiopia.

    Science.gov (United States)

    Terefe, Endashaw; Haile, Aynalem; Mulatu, Wudyalew; Dessie, Tadelle; Mwai, Okeyo

    2015-03-01

    The study was conducted to characterize the morphological features of Mursi cattle breed and to identify the species of trypanosome infecting the cattle and its prevalence in these traditionally managed cattle in the Bodi and Mursi pastoral communities. Cattle body description and measurements were made on 201 matured animals. Blood samples were collected from 409 animals into heparin-treated capillary tubes and were centrifuged to 12,000 rpm for 5 min to identify trypanosome species from the wet smeared buffy coat and to estimate the degree of anemia (PCV). Tsetse flies were collected using phenol-treated biconical trap and the caught flies identified to species level. The breed possesses variable coat color pattern, coat color type, and have small to medium hump size on the thoracic vertebrae. Body measurement of Mursi cattle in the two locations did not show significant differences except chest girth, rump width, and horn length. Trypanosome prevalence in the Mursi cattle breed was 6.1%. The highest trypanosome infection was caused by Trypanosoma congolense (56%) followed by Trypanosoma vivax (40%) and Trypanosoma brucei (4%). Trypanosome prevalence significantly varies between dry (2.0%) and late rainy (10.1%) seasons (P < 0.001) and between lean (11.9%) and medium (2.4%) body condition score (P < 0.01). The PCV value was 22.1 ± 0.5%, which is significantly varied with season (P < 0.01) and parasitism (P < 0.001). Parasitaemic cattle show the lowest PCV value (20.4 ± 1%) than aparasitaemic (23.7 ± 0.3%) cattle and cattle with lean BCS showed the lowest (P < 0.0001) PCV value (20.4 ± 0.6%). Tsetse fly species identified in the study area were Glossina pallidipes, Glossina morsitans submorsitans, and Glossina fuscipes. The number of flies captured in late rainy season was higher than in dry season (P < 0.01). Despite the existence of trypanosome and high tsetse fly infestation in the areas, large proportion of the Mursi

  20. Generation of a nanobody targeting the paraflagellar rod protein of trypanosomes.

    Directory of Open Access Journals (Sweden)

    Emmanuel Obishakin

    Full Text Available Trypanosomes are protozoan parasites that cause diseases in humans and livestock for which no vaccines are available. Disease eradication requires sensitive diagnostic tools and efficient treatment strategies. Immunodiagnostics based on antigen detection are preferable to antibody detection because the latter cannot differentiate between active infection and cure. Classical monoclonal antibodies are inaccessible to cryptic epitopes (based on their size-150 kDa, costly to produce and require cold chain maintenance, a condition that is difficult to achieve in trypanosomiasis endemic regions, which are mostly rural. Nanobodies are recombinant, heat-stable, small-sized (15 kDa, antigen-specific, single-domain, variable fragments derived from heavy chain-only antibodies in camelids. Because of numerous advantages over classical antibodies, we investigated the use of nanobodies for the targeting of trypanosome-specific antigens and diagnostic potential. An alpaca was immunized using lysates of Trypanosoma evansi. Using phage display and bio-panning techniques, a cross-reactive nanobody (Nb392 targeting all trypanosome species and isolates tested was selected. Imunoblotting, immunofluorescence microscopy, immunoprecipitation and mass spectrometry assays were combined to identify the target recognized. Nb392 targets paraflagellar rod protein (PFR1 of T. evansi, T. brucei, T. congolense and T. vivax. Two different RNAi mutants with defective PFR assembly (PFR2RNAi and KIF9BRNAi were used to confirm its specificity. In conclusion, using a complex protein mixture for alpaca immunization, we generated a highly specific nanobody (Nb392 that targets a conserved trypanosome protein, i.e., PFR1 in the flagella of trypanosomes. Nb392 is an excellent marker for the PFR and can be useful in the diagnosis of trypanosomiasis. In addition, as demonstrated, Nb392 can be a useful research or PFR protein isolation tool.

  1. Functional Insight From Fruit Flies on Human ADHD Candidate Genes

    DEFF Research Database (Denmark)

    Rohde, Palle Duun; Demontis, Ditte; Arvidson, Sandra Marie Neumann

    2015-01-01

    , and increased risk of mental comorbidities, makes ADHD a disorder with high individual and societal costs. We use Drosophila melanogaster as a model to investigate the phenotypic consequences of gene disruption of 14 genes with human orthologs, selected by their proposed contribution to increased risk...... for other mutants. Decreased activity level, when treated with dexamphetamine, is seen when using other ADHD animal models. Our findings suggest involvement of the proposed candidate genes Genes, Brain, and Behavior 2015 36 Talk Abstracts in hyperactivity in D. melanogaster, providing functional evidence...

  2. Comparison of inter- and intraspecies variation in humans and fruit flies

    Directory of Open Access Journals (Sweden)

    Juliann Shih

    2015-03-01

    Full Text Available Variation is essential to species survival and adaptation during evolution. This variation is conferred by the imperfection of biochemical processes, such as mutations and alterations in DNA sequences, and can also be seen within genomes through processes such as the generation of antibodies. Recent sequencing projects have produced multiple versions of the genomes of humans and fruit flies (Drosophila melanogaster. These give us a chance to study how individual gene sequences vary within and between species. Here we arranged human and fly genes in orthologous pairs and compared such within-species variability with their degree of conservation between flies and humans. We observed that a significant number of proteins associated with mRNA translation are highly conserved between species and yet are highly variable within each species. The fact that we observe this in two species whose lineages separated more than 700 million years ago suggests that this is the result of a very ancient process. We hypothesize that this effect might be attributed to a positive selection for variability of virus-interacting proteins that confers a general resistance to viral hijacking of the mRNA translation machinery within populations. Our analysis points to this and to other processes resulting in positive selection for gene variation.

  3. Social motility in African trypanosomes: fact or model?

    Science.gov (United States)

    Bastin, Philippe; Rotureau, Brice

    2015-02-01

    African trypanosomes grown on agarose plates exhibit behaviours akin to social motility. This phenomenon has not been observed in vivo so far but recently turned out to be instrumental in the definition of two specific stages of the parasite cycle and as a tool to probe for trypanosome sensing functions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Sex-Specific Selection and Sex-Biased Gene Expression in Humans and Flies.

    Science.gov (United States)

    Cheng, Changde; Kirkpatrick, Mark

    2016-09-01

    Sexual dimorphism results from sex-biased gene expression, which evolves when selection acts differently on males and females. While there is an intimate connection between sex-biased gene expression and sex-specific selection, few empirical studies have studied this relationship directly. Here we compare the two on a genome-wide scale in humans and flies. We find a distinctive "Twin Peaks" pattern in humans that relates the strength of sex-specific selection, quantified by genetic divergence between male and female adults at autosomal loci, to the degree of sex-biased expression. Genes with intermediate degrees of sex-biased expression show evidence of ongoing sex-specific selection, while genes with either little or completely sex-biased expression do not. This pattern apparently results from differential viability selection in males and females acting in the current generation. The Twin Peaks pattern is also found in Drosophila using a different measure of sex-specific selection acting on fertility. We develop a simple model that successfully recapitulates the Twin Peaks. Our results suggest that many genes with intermediate sex-biased expression experience ongoing sex-specific selection in humans and flies.

  5. Sex-Specific Selection and Sex-Biased Gene Expression in Humans and Flies.

    Directory of Open Access Journals (Sweden)

    Changde Cheng

    2016-09-01

    Full Text Available Sexual dimorphism results from sex-biased gene expression, which evolves when selection acts differently on males and females. While there is an intimate connection between sex-biased gene expression and sex-specific selection, few empirical studies have studied this relationship directly. Here we compare the two on a genome-wide scale in humans and flies. We find a distinctive "Twin Peaks" pattern in humans that relates the strength of sex-specific selection, quantified by genetic divergence between male and female adults at autosomal loci, to the degree of sex-biased expression. Genes with intermediate degrees of sex-biased expression show evidence of ongoing sex-specific selection, while genes with either little or completely sex-biased expression do not. This pattern apparently results from differential viability selection in males and females acting in the current generation. The Twin Peaks pattern is also found in Drosophila using a different measure of sex-specific selection acting on fertility. We develop a simple model that successfully recapitulates the Twin Peaks. Our results suggest that many genes with intermediate sex-biased expression experience ongoing sex-specific selection in humans and flies.

  6. Field and experimental evidence of a new caiman trypanosome species closely phylogenetically related to fish trypanosomes and transmitted by leeches

    Directory of Open Access Journals (Sweden)

    Bruno R. Fermino

    2015-12-01

    Full Text Available Trypanosoma terena and Trypanosoma ralphi are known species of the South American crocodilians Caiman crocodilus, Caiman yacare and Melanosuchus niger and are phylogenetically related to the tsetse-transmitted Trypanosoma grayi of the African Crocodylus niloticus. These trypanosomes form the Crocodilian clade of the terrestrial clade of the genus Trypanosoma. A PCR-survey for trypanosomes in caiman blood samples and in leeches taken from caimans revealed unknown trypanosome diversity and frequent mixed infections. Phylogenies based on SSU (small subunit of rRNA and gGAPDH (glycosomal Glyceraldehyde Phosphate Dehydrogenase gene sequences revealed a new trypanosome species clustering with T. terena and T. ralphi in the crocodilian clade and an additional new species nesting in the distant Aquatic clade of trypanosomes, which is herein named Trypanosoma clandestinus n. sp. This new species was found in Caiman yacare, Caiman crocodilus and M. niger from the Pantanal and Amazonian biomes in Brazil. Large numbers of dividing epimastigotes and unique thin and long trypomastigotes were found in the guts of leeches (Haementeria sp. removed from the mouths of caimans. The trypanosomes recovered from the leeches had sequences identical to those of T. clandestinus of caiman blood samples. Experimental infestation of young caimans (Caiman yacare with infected leeches resulted in long-lasting T. clandestinus infections that permitted us to delineate its life cycle. In contrast to T. terena, T. ralphi and T. grayi, which are detectable by hemoculturing, microscopy and standard PCR of caiman blood, T. clandestinus passes undetected by these methods due to very low parasitemia and could be detected solely by the more sensitive nested PCR method. T. clandestinus n. sp. is the first crocodilian trypanosome known to be transmitted by leeches and positioned in the aquatic clade closest to fish trypanosomes. Our data show that caimans can host trypanosomes

  7. Field and experimental evidence of a new caiman trypanosome species closely phylogenetically related to fish trypanosomes and transmitted by leeches

    Science.gov (United States)

    Fermino, Bruno R.; Paiva, Fernando; Soares, Priscilla; Tavares, Luiz Eduardo R.; Viola, Laerte B.; Ferreira, Robson C.; Botero-Arias, Robinson; de-Paula, Cátia D.; Campaner, Marta; Takata, Carmen S.A.; Teixeira, Marta M.G.; Camargo, Erney P.

    2015-01-01

    Trypanosoma terena and Trypanosoma ralphi are known species of the South American crocodilians Caiman crocodilus, Caiman yacare and Melanosuchus niger and are phylogenetically related to the tsetse-transmitted Trypanosoma grayi of the African Crocodylus niloticus. These trypanosomes form the Crocodilian clade of the terrestrial clade of the genus Trypanosoma. A PCR-survey for trypanosomes in caiman blood samples and in leeches taken from caimans revealed unknown trypanosome diversity and frequent mixed infections. Phylogenies based on SSU (small subunit) of rRNA and gGAPDH (glycosomal Glyceraldehyde Phosphate Dehydrogenase) gene sequences revealed a new trypanosome species clustering with T. terena and T. ralphi in the crocodilian clade and an additional new species nesting in the distant Aquatic clade of trypanosomes, which is herein named Trypanosoma clandestinus n. sp. This new species was found in Caiman yacare, Caiman crocodilus and M. niger from the Pantanal and Amazonian biomes in Brazil. Large numbers of dividing epimastigotes and unique thin and long trypomastigotes were found in the guts of leeches (Haementeria sp.) removed from the mouths of caimans. The trypanosomes recovered from the leeches had sequences identical to those of T. clandestinus of caiman blood samples. Experimental infestation of young caimans (Caiman yacare) with infected leeches resulted in long-lasting T. clandestinus infections that permitted us to delineate its life cycle. In contrast to T. terena, T. ralphi and T. grayi, which are detectable by hemoculturing, microscopy and standard PCR of caiman blood, T. clandestinus passes undetected by these methods due to very low parasitemia and could be detected solely by the more sensitive nested PCR method. T. clandestinus n. sp. is the first crocodilian trypanosome known to be transmitted by leeches and positioned in the aquatic clade closest to fish trypanosomes. Our data show that caimans can host trypanosomes of the aquatic or

  8. Early invasion of brain parenchyma by African trypanosomes

    National Research Council Canada - National Science Library

    Frevert, Ute; Movila, Alexandru; Nikolskaia, Olga V; Raper, Jayne; Mackey, Zachary B; Abdulla, Maha; McKerrow, James; Grab, Dennis J

    2012-01-01

    .... Based mostly on data from animal models, it is currently thought that trypanosome entry into the brain occurs by initial infection of the choroid plexus and the circumventricular organs followed days...

  9. Generation of anti-trypanosomal agents through concise synthesis and structural diversification of sesquiterpene analogues.

    Science.gov (United States)

    Oguri, Hiroki; Hiruma, Takahisa; Yamagishi, Yutaka; Oikawa, Hideaki; Ishiyama, Aki; Otoguro, Kazuhiko; Yamada, Haruki; Ōmura, Satoshi

    2011-05-11

    To access high-quality small-molecule libraries to screen lead candidates for neglected diseases exemplified by human African trypanosomiasis, we sought to develop a synthetic process that would produce collections of cyclic scaffolds relevant to an assortment of natural products exhibiting desirable biological activities. By extracting the common structural features among several sesquiterpenes, including artemisinin, anthecularin, and transtaganolides, we designed six types of scaffolds with systematic structural variations consisting of three types of stereochemical relationships on the sp(3) ring-junctions and two distinct arrays of tricyclic frameworks. A modular and stereodivergent assembly of dienynes exploiting a versatile manifold produced a series of cyclization precursors. Divergent cyclizations of the dienynes employing tandem ring-closing metathesis reactions overrode variant reactivities of the cyclization precursors, leading to the six canonical sets of the tricyclic scaffolds incorporating a diene group. Screenings of trypanosomal activities of the canonical sets, as well as regio- and stereoisomers of the tricyclic dienes, allowed generation of several anti-trypanosomal agents defining the three-dimensional shape of the pharmacophore. The candidate tricyclic dienes were selected by primary screenings and further subjected to installation of a peroxide bridge, which generated artemisinin analogues that exhibited potent in vitro anti-trypanosomal activities comparable or even superior to those of artemisinin and the approved drugs, suramin and eflornithine.

  10. Trypanosome species in neo-tropical bats: biological, evolutionary and epidemiological implications.

    Science.gov (United States)

    Ramírez, Juan David; Tapia-Calle, Gabriela; Muñoz-Cruz, Geissler; Poveda, Cristina; Rendón, Lina M; Hincapié, Eduwin; Guhl, Felipe

    2014-03-01

    Bats (Chiroptera) are the only mammals naturally able to fly. Due to this characteristic they play a relevant ecological role in the niches they inhabit. These mammals spread infectious diseases from enzootic to domestic foci. Rabbies, SARS, fungi, ebola and trypanosomes are the most common pathogens these animals may host. We conducted intensive sampling of bats from the phyllostomidae, vespertilionidae and emballonuridae families in six localities from Casanare department in eastern Colombia. Blood-EDTA samples were obtained and subsequently submitted to analyses of mitochondrial and nuclear genetic markers in order to conduct barcoding analyses to discriminate trypanosome species. The findings according to the congruence of the three molecular markers suggest the occurrence of Trypanosoma cruzi cruzi (51%), T. c. marinkellei (9%), T. dionisii (13%), T. rangeli (21%), T. evansi (4%) and T. theileri (2%) among 107 positive bat specimens. Regarding the T. cruzi DTUs, we observed the presence of TcI (60%), TcII (15%), TcIII (7%), TcIV (7%) and TcBAT (11%) being the first evidence to our concern of the foreseen genotype TcBAT in Colombia. These results allowed us to propose reliable hypotheses regarding the ecology and biology of the bats circulating in the area including the enigmatic question whether TcBAT should be considered a novel DTU. The epidemiological and evolutionary implications of these findings are herein discussed.

  11. Constraints to estimating the prevalence of trypanosome infections in East African zebu cattle

    Directory of Open Access Journals (Sweden)

    Cox Andrew P

    2010-09-01

    Full Text Available Abstract Background In East Africa, animal trypanosomiasis is caused by many tsetse transmitted protozoan parasites including Trypanosoma vivax, T. congolense and subspecies of T. brucei s.l. (T. b. brucei and zoonotic human infective T. b. rhodesiense that may co-circulate in domestic and wild animals. Accurate species-specific prevalence measurements of these parasites in animal populations are complicated by mixed infections of trypanosomes within individual hosts, low parasite densities and difficulties in conducting field studies. Many Polymerase Chain Reaction (PCR based diagnostic tools are available to characterise and quantify infection in animals. These are important for assessing the contribution of infections in animal reservoirs and the risk posed to humans from zoonotic trypanosome species. New matrices for DNA capture have simplified large scale field PCR analyses but few studies have examined the impact of these techniques on prevalence estimations. Results The Whatman FTA matrix has been evaluated using a random sample of 35 village zebu cattle from a population naturally exposed to trypanosome infection. Using a generic trypanosome-specific PCR, prevalence was systematically evaluated. Multiple PCR samples taken from single FTA cards demonstrated that a single punch from an FTA card is not sufficient to confirm the infectivity status of an individual animal as parasite DNA is unevenly distributed across the card. At low parasite densities in the host, this stochastic sampling effect results in underestimation of prevalence based on single punch PCR testing. Repeated testing increased the estimated prevalence of all Trypanosoma spp. from 9.7% to 86%. Using repeat testing, a very high prevalence of pathogenic trypanosomes was detected in these local village cattle: T. brucei (34.3%, T. congolense (42.9% and T. vivax (22.9%. Conclusions These results show that, despite the convenience of Whatman FTA cards and specific PCR based

  12. Ribosome Biogenesis in African Trypanosomes Requires Conserved and Trypanosome-Specific Factors

    Science.gov (United States)

    Umaer, Khan; Ciganda, Martin

    2014-01-01

    Large ribosomal subunit protein L5 is responsible for the stability and trafficking of 5S rRNA to the site of eukaryotic ribosomal assembly. In Trypanosoma brucei, in addition to L5, trypanosome-specific proteins P34 and P37 also participate in this process. These two essential proteins form a novel preribosomal particle through interactions with both the ribosomal protein L5 and 5S rRNA. We have generated a procyclic L5 RNA interference cell line and found that L5 itself is a protein essential for trypanosome growth, despite the presence of other 5S rRNA binding proteins. Loss of L5 decreases the levels of all large-subunit rRNAs, 25/28S, 5.8S, and 5S rRNAs, but does not alter small-subunit 18S rRNA. Depletion of L5 specifically reduced the levels of the other large ribosomal proteins, L3 and L11, whereas the steady-state levels of the mRNA for these proteins were increased. L5-knockdown cells showed an increase in the 40S ribosomal subunit and a loss of the 60S ribosomal subunits, 80S monosomes, and polysomes. In addition, L5 was involved in the processing and maturation of precursor rRNAs. Analysis of polysomal fractions revealed that unprocessed rRNA intermediates accumulate in the ribosome when L5 is depleted. Although we previously found that the loss of P34 and P37 does not result in a change in the levels of L5, the loss of L5 resulted in an increase of P34 and P37 proteins, suggesting the presence of a compensatory feedback loop. This study demonstrates that ribosomal protein L5 has conserved functions, in addition to nonconserved trypanosome-specific features, which could be targeted for drug intervention. PMID:24706018

  13. Lessons from "lower" organisms: what worms, flies, and zebrafish can teach us about human energy metabolism.

    Directory of Open Access Journals (Sweden)

    Amnon Schlegel

    2007-11-01

    Full Text Available A pandemic of metabolic diseases (atherosclerosis, diabetes mellitus, and obesity, unleashed by multiple social and economic factors beyond the control of most individuals, threatens to diminish human life span for the first time in the modern era. Given the redundancy and inherent complexity of processes regulating the uptake, transport, catabolism, and synthesis of nutrients, magic bullets to target these diseases will be hard to find. Recent studies using the worm Caenorhabditis elegans, the fly Drosophila melanogaster, and the zebrafish Danio rerio indicate that these "lower" metazoans possess unique attributes that should help in identifying, investigating, and even validating new pharmaceutical targets for these diseases. We summarize findings in these organisms that shed light on highly conserved pathways of energy homeostasis.

  14. Trypanosome lytic factor, an antimicrobial high-density lipoprotein, ameliorates Leishmania infection.

    Directory of Open Access Journals (Sweden)

    Marie Samanovic

    2009-01-01

    Full Text Available Innate immunity is the first line of defense against invading microorganisms. Trypanosome Lytic Factor (TLF is a minor sub-fraction of human high-density lipoprotein that provides innate immunity by completely protecting humans from infection by most species of African trypanosomes, which belong to the Kinetoplastida order. Herein, we demonstrate the broader protective effects of human TLF, which inhibits intracellular infection by Leishmania, a kinetoplastid that replicates in phagolysosomes of macrophages. We show that TLF accumulates within the parasitophorous vacuole of macrophages in vitro and reduces the number of Leishmania metacyclic promastigotes, but not amastigotes. We do not detect any activation of the macrophages by TLF in the presence or absence of Leishmania, and therefore propose that TLF directly damages the parasite in the acidic parasitophorous vacuole. To investigate the physiological relevance of this observation, we have reconstituted lytic activity in vivo by generating mice that express the two main protein components of TLFs: human apolipoprotein L-I and haptoglobin-related protein. Both proteins are expressed in mice at levels equivalent to those found in humans and circulate within high-density lipoproteins. We find that TLF mice can ameliorate an infection with Leishmania by significantly reducing the pathogen burden. In contrast, TLF mice were not protected against infection by the kinetoplastid Trypanosoma cruzi, which infects many cell types and transiently passes through a phagolysosome. We conclude that TLF not only determines species specificity for African trypanosomes, but can also ameliorate an infection with Leishmania, while having no effect on T. cruzi. We propose that TLFs are a component of the innate immune system that can limit infections by their ability to selectively damage pathogens in phagolysosomes within the reticuloendothelial system.

  15. The evolution of pathogenic trypanosomes A evolução dos tripanossomas patogênicos

    Directory of Open Access Journals (Sweden)

    Jamie R. Stevens

    1999-10-01

    Full Text Available In the absence of a fossil record, the evolution of protozoa has until recently largely remained a matter for speculation. However, advances in molecular methods and phylogenetic analysis are now allowing interpretation of the "history written in the genes". This review focuses on recent progress in reconstruction of trypanosome phylogeny based on molecular data from ribosomal RNA, the miniexon and protein-coding genes. Sufficient data have now been gathered to demonstrate unequivocally that trypanosomes are monophyletic; the phylogenetic trees derived can serve as a framework to reinterpret the biology, taxonomy and present day distribution of trypanosome species, providing insights into the coevolution of trypanosomes with their vertebrate hosts and vectors. Different methods of dating the divergence of trypanosome lineages give rise to radically different evolutionary scenarios and these are reviewed. In particular, the use of one such biogeographically based approach provides new insights into the coevolution of the pathogens, Trypanosoma brucei and Trypanosoma cruzi, with their human hosts and the history of the diseases with which they are associated.Os avanços recentes obtidos com os métodos moleculares e com a análise filogenética permitem atualmente interpretar a "história escrita nos genes", na ausência de um registro fóssil. A presente revisão se concentra em avanços recentes na reconstrução da filogenia dos tripanossomas, com base em dados moleculares obtidos do ARN ribossômico, do miniexon e dos genes codificadores de proteínas. Os dados já coletados demonstram inequivocamente que os tripanossomas são monofiléticos; as árvores filogenéticas derivadas podem servir como arcabouço para reinterpretar a biologia, taxonomia e distribuição atual das espécies de tripanossomas, elucidando sua co-evolução com os hospedeiros vertebrados e vetores. Diferentes métodos para datar a divergência das linhagens de

  16. Potential risk of viral transmission from flying foxes to domestic animals and humans on the southern coast of West Java, Indonesia.

    Science.gov (United States)

    Basri, Chaerul; Arifin, Eko Muhammad Zainal; Takemae, Hitoshi; Hengjan, Yupadee; Iida, Keisuke; Sudarnika, Etih; Zahid, Abdul; Soejoedono, Retno Damayanti; Susetya, Heru; Sumiarto, Bambang; Kobayashi, Ryosuke; Agungpriyono, Srihadi; Hondo, Eiichi

    2017-09-29

    Flying foxes have been considered to be involved in the transmission of serious infectious diseases to humans. Using questionnaires, we aimed to determine the direct and/or indirect contacts of flying foxes in an Indonesian nature conservation area with domestic animals and humans living in the surrounding area. We surveyed 150 residents of 10 villages in West Java. Villages were classified into 3 groups: inside and/or within 1 km from the outer border of the conservation area and 1-5 km or 5-10 km away from the reserve's outer border. Data were collected by direct interview using a structured questionnaire consisting of the respondent characteristics (age, sex and occupation); histories of contacts between flying foxes and humans, dogs and other domestic animals; and knowledge about infectious diseases, mainly rabies, in flying foxes. We found that flying foxes from the nature conservation area often enter residential areas at night to look for food, especially during the fruit season. In these residential areas, flying foxes had direct contacts with humans and a few contacts with domestic animals, especially dogs. People who encounter flying foxes seldom used personal protective equipment, such as leather gloves, goggles and caps. The residents living around the conservation area mostly had poor knowledge about flying foxes and disease transmission. This situation shows that the population in this region is at a quite high risk for contracting infectious diseases from flying foxes.

  17. LORD OF THE FLIES: A NARRATIVE OF HUMAN ESSENCE AND THE DICTATORSHIP AGE

    Directory of Open Access Journals (Sweden)

    Vedi AŞKAROĞLU

    2016-04-01

    Full Text Available Lord of the Flies is an anti-utopic (dystopic novel by the English author William Golding, who wrote about how human’s primitive aspect can peep out by portraying kids whose ages vary from 5 to 12 on a deserted island. That kids are chosen as the characters of the novel makes it possible to observe in an empirical way the human nature in its nakedness far away from civilization and what it offers with its norms, education and social intitutions. The island, as a space, is significant for it offers a clear vision of how primitive instincts can appear when there is no outside interference. In our article, first we have made a theoretical discussion on primitive aspect of humans and then analysed how they might become savage in a setting away from civilization. In our analysis, we have found out that human nature is likely to transgress into savagery in a setting devoid of laws, moral norms and social institutions. The reason why we have chosen such a topic is directly related to a need to better understand the recent devastating violance and hatred, which ravage our world and close geography in particular.

  18. The occurrence of hazardous volatile elements and nanoparticles in Bulgarian coal fly ashes and the effect on human health exposure

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Luis F.O., E-mail: lfsoliveira@univates.br [Centro Universitario Univates, Pro Reitoria de Pesquisa Estensao e Pos Graduacao, Programa de Pos Graduacao Ambiente e Desenvolvimento (Brazil); Environmental Science and Nanotechnology Department, Catarinense Institute of Environmental Research and Human Development - IPADHC, Capivari de Baixo, Santa Catarina (Brazil); DaBoit, Katia [Department of Environmental Medicine, Catarinense Institute of Environmental Research and Human Development - IPADHC, Capivari de Baixo, Santa Catarina (Brazil); Sampaio, Carlos H. [Universidade Federal do Rio Grande do Sul, Escola de Engenharia, Departamento de Metalurgia, Centro de Tecnologia, Av. Bento Goncalves, 9500, Bairro Agronomia, CEP: 91501-970, Porto Alegre - RS (Brazil); Jasper, Andre [Centro Universitario Univates, Pro Reitoria de Pesquisa Estensao e Pos Graduacao, Programa de Pos Graduacao Ambiente e Desenvolvimento (Brazil); Andrade, Maria L. [Department of Plant Biology and Soil Science, University of Vigo, 36310 Vigo (Spain); Kostova, Irena J. [Sofia University ' St. Kliment Ohridski' , Department of Geology, Paleontology and Fossil Fuels, 15, Tzar Osvoboditel Blvd., 1000 Sofia (Bulgaria); and others

    2012-02-01

    Low-rank, high-mineral matter Bulgarian coals were studied using a variety of chemical, optical, and electron beam methods. The larger fly ash carbon phases include charred carbons in contrast to coked carbons present in the fly ashes of bituminous-coal-derived fly ashes. Nanoscale carbons include multi-walled carbon nanotubes (MWCNTs) encapsulating Hg, Se, and As, among other elements. In addition to the glass which dominates the fly ash, relatively coarse 'rock fragments', consisting of an unmelted to partially melted core surrounded by a glassy rim, are present in the fly ash. Nano-scale minerals can contain hazardous elements and, along with metal-bearing multiwalled nanotubes, can be a path for the entry of hazardous particles into the lungs and other organs. Highlights: Black-Right-Pointing-Pointer We model Bulgarian power plants which have regulated minerals nanoparticles can contain hazardous elements. Black-Right-Pointing-Pointer We study changes in the level of information about nanominerals importance and the effect on human health exposure. Black-Right-Pointing-Pointer Increasing information will increase quality if power plants procedures are similar.

  19. Conditional Expression of Human 15-Lipoxygenase-1 in Mouse Prostate Induces Prostatic Intraepithelial Neoplasia: The FLiMP Mouse Model

    Directory of Open Access Journals (Sweden)

    Uddhav P. Kelavkar

    2006-06-01

    Full Text Available The incidence and mortality of prostate cancer (PCa vary greatly in different geographic regions, for which lifestyle factors, such as dietary fat intake, have been implicated. Human 15-lipoxygenase-1 (h15-LO-1, which metabolizes polyunsaturated fatty acids, is a highly regulated, tissue-specific, lipid-peroxidating enzyme that functions in physiological membrane remodeling and in the pathogenesis of atherosclerosis, inflammation, and carcinogenesis. We have shown that aberrant overexpression of 15-LO-1 occurs in human PCa, particularly high-grade PCa, and in high-grade prostatic intraepithelial neoplasia (HGPIN, and that the murine orthologue is increased in SV40-based genetically engineered mouse (GEM models of PCa, such as LADY and TRansgenic Adenocarcinoma of Mouse Prostate. To further define the role of 15-LO-1 in prostate carcinogenesis, we established a novel GEM model with targeted overexpression of h15-LO-1 in the prostate [human fifteen lipoxygenase-1 in mouse prostate (FLiMP]. We used a Cre- mediated and a loxP-mediated recombination strategy to target h15-LO-1 specifically to the prostate of C57BL/6 mice. Wild-type (wt, FLiMP+/-, and FLiMP+/+ mice aged 7 to 21, 24 to 28, and 35 weeks were characterized by histopathology, immunohistochemistry (IHC, and DNA/RNA and enzyme analyses. Compared to wt mice, h15-LO-1 enzyme activity was increased similarly in both homozygous FLiMP+/+ and hemizygous FLiMP+/- prostates. Dorsolateral and ventral prostates of FLiMP mice showed focal and progressive epithelial hyperplasia with nuclear atypia, indicative of the definition of mouse prostatic intraepithelial neoplasia (mPIN according to the National Cancer Institute. These foci showed increased proliferation by Ki-67 IHC. No progression to invasive PCa was noted up to 35 weeks. By IHC, h15-LO-1 expression was limited to luminal epithelial cells, with increased expression in mPIN foci (similar to human HGPIN. In summary, targeted overexpression of h

  20. Overexpression of human and fly frataxins in Drosophila provokes deleterious effects at biochemical, physiological and developmental levels.

    Directory of Open Access Journals (Sweden)

    Juan A Navarro

    Full Text Available BACKGROUND: Friedreich's ataxia (FA, the most frequent form of inherited ataxias in the Caucasian population, is caused by a reduced expression of frataxin, a highly conserved protein. Model organisms have contributed greatly in the efforts to decipher the function of frataxin; however, the precise function of this protein remains elusive. Overexpression studies are a useful approach to investigate the mechanistic actions of frataxin; however, the existing literature reports contradictory results. To further investigate the effect of frataxin overexpression, we analyzed the consequences of overexpressing human (FXN and fly (FH frataxins in Drosophila. METHODOLOGY/PRINCIPAL FINDINGS: We obtained transgenic flies that overexpressed human or fly frataxins in a general pattern and in different tissues using the UAS-GAL4 system. For both frataxins, we observed deleterious effects at the biochemical, histological and behavioral levels. Oxidative stress is a relevant factor in the frataxin overexpression phenotypes. Systemic frataxin overexpression reduces Drosophila viability and impairs the normal embryonic development of muscle and the peripheral nervous system. A reduction in the level of aconitase activity and a decrease in the level of NDUF3 were also observed in the transgenic flies that overexpressed frataxin. Frataxin overexpression in the nervous system reduces life span, impairs locomotor ability and causes brain degeneration. Frataxin aggregation and a misfolding of this protein have been shown not to be the mechanism that is responsible for the phenotypes that have been observed. Nevertheless, the expression of human frataxin rescues the aconitase activity in the fh knockdown mutant. CONCLUSION/SIGNIFICANCE: Our results provide in vivo evidence of a functional equivalence for human and fly frataxins and indicate that the control of frataxin expression is important for treatments that aim to increase frataxin levels.

  1. Overexpression of Human and Fly Frataxins in Drosophila Provokes Deleterious Effects at Biochemical, Physiological and Developmental Levels

    Science.gov (United States)

    Soriano, Sirena; Botella, José A.; Schneuwly, Stephan; Martínez-Sebastián, María J.; Moltó, María D.

    2011-01-01

    Background Friedreich's ataxia (FA), the most frequent form of inherited ataxias in the Caucasian population, is caused by a reduced expression of frataxin, a highly conserved protein. Model organisms have contributed greatly in the efforts to decipher the function of frataxin; however, the precise function of this protein remains elusive. Overexpression studies are a useful approach to investigate the mechanistic actions of frataxin; however, the existing literature reports contradictory results. To further investigate the effect of frataxin overexpression, we analyzed the consequences of overexpressing human (FXN) and fly (FH) frataxins in Drosophila. Methodology/Principal Findings We obtained transgenic flies that overexpressed human or fly frataxins in a general pattern and in different tissues using the UAS-GAL4 system. For both frataxins, we observed deleterious effects at the biochemical, histological and behavioral levels. Oxidative stress is a relevant factor in the frataxin overexpression phenotypes. Systemic frataxin overexpression reduces Drosophila viability and impairs the normal embryonic development of muscle and the peripheral nervous system. A reduction in the level of aconitase activity and a decrease in the level of NDUF3 were also observed in the transgenic flies that overexpressed frataxin. Frataxin overexpression in the nervous system reduces life span, impairs locomotor ability and causes brain degeneration. Frataxin aggregation and a misfolding of this protein have been shown not to be the mechanism that is responsible for the phenotypes that have been observed. Nevertheless, the expression of human frataxin rescues the aconitase activity in the fh knockdown mutant. Conclusion/Significance Our results provide in vivo evidence of a functional equivalence for human and fly frataxins and indicate that the control of frataxin expression is important for treatments that aim to increase frataxin levels. PMID:21779322

  2. Gastrointestinal stem cells in health and disease: from flies to humans

    Directory of Open Access Journals (Sweden)

    Hongjie Li

    2016-05-01

    Full Text Available The gastrointestinal tract of complex metazoans is highly compartmentalized. It is lined by a series of specialized epithelia that are regenerated by specific populations of stem cells. To maintain tissue homeostasis, the proliferative activity of stem and/or progenitor cells has to be carefully controlled and coordinated with regionally distinct programs of differentiation. Metaplasias and dysplasias, precancerous lesions that commonly occur in the human gastrointestinal tract, are often associated with the aberrant proliferation and differentiation of stem and/or progenitor cells. The increasingly sophisticated characterization of stem cells in the gastrointestinal tract of mammals and of the fruit fly Drosophila has provided important new insights into these processes and into the mechanisms that drive epithelial dysfunction. In this Review, we discuss recent advances in our understanding of the establishment, maintenance and regulation of diverse intestinal stem cell lineages in the gastrointestinal tract of Drosophila and mice. We also discuss the field's current understanding of the pathogenesis of epithelial dysfunctions.

  3. Gastrointestinal stem cells in health and disease: from flies to humans

    Science.gov (United States)

    Li, Hongjie; Jasper, Heinrich

    2016-01-01

    ABSTRACT The gastrointestinal tract of complex metazoans is highly compartmentalized. It is lined by a series of specialized epithelia that are regenerated by specific populations of stem cells. To maintain tissue homeostasis, the proliferative activity of stem and/or progenitor cells has to be carefully controlled and coordinated with regionally distinct programs of differentiation. Metaplasias and dysplasias, precancerous lesions that commonly occur in the human gastrointestinal tract, are often associated with the aberrant proliferation and differentiation of stem and/or progenitor cells. The increasingly sophisticated characterization of stem cells in the gastrointestinal tract of mammals and of the fruit fly Drosophila has provided important new insights into these processes and into the mechanisms that drive epithelial dysfunction. In this Review, we discuss recent advances in our understanding of the establishment, maintenance and regulation of diverse intestinal stem cell lineages in the gastrointestinal tract of Drosophila and mice. We also discuss the field's current understanding of the pathogenesis of epithelial dysfunctions. PMID:27112333

  4. Human African trypanosomiasis.

    Science.gov (United States)

    Lejon, Veerle; Bentivoglio, Marina; Franco, José Ramon

    2013-01-01

    Human African trypanosomiasis or sleeping sickness is a neglected tropical disease that affects populations in sub-Saharan Africa. The disease is caused by infection with the gambiense and rhodesiense subspecies of the extracellular parasite Trypanosoma brucei, and is transmitted to humans by bites of infected tsetse flies. The disease evolves in two stages, the hemolymphatic and meningoencephalitic stages, the latter being defined by central nervous system infection after trypanosomal traversal of the blood-brain barrier. African trypanosomiasis, which leads to severe neuroinflammation, is fatal without treatment, but the available drugs are toxic and complicated to administer. The choice of medication is determined by the infecting parasite subspecies and disease stage. Clinical features include a constellation of nonspecific symptoms and signs with evolving neurological and psychiatric alterations and characteristic sleep-wake disturbances. Because of the clinical profile variability and insidiously progressive central nervous system involvement, disease staging is currently based on cerebrospinal fluid examination, which is usually performed after the finding of trypanosomes in blood or other body fluids. No vaccine being available, control of human African trypanosomiasis relies on diagnosis and treatment of infected patients, assisted by vector control. Better diagnostic tools and safer, easy to use drugs are needed to facilitate elimination of the disease.

  5. Orally Active and Selective Tubulin Inhibitors as Anti-Trypanosome Agents.

    Directory of Open Access Journals (Sweden)

    Vishal Nanavaty

    Full Text Available There is an urgent need to develop a safe, effective, orally active, and inexpensive therapy for African trypanosomiasis due to the drawbacks of current drugs. Selective tubulin inhibitors have the potential to be promising drug candidates for the treatment of this disease, which is based on the tubulin protein structural difference between mammalian and trypanosome cells. We propose to identify novel tubulin inhibitors from a compound library developed based on the lead compounds that selectively target trypanosomiasis.We used Trypanosoma brucei brucei as the parasite model, and human normal kidney cells and mouse microphage cells as the host model. Growth rates of both trypanosomes and mammalian cells were determined as a means to screen compounds that selectively inhibit the proliferation of parasites. Furthermore, we examined the cell cycle profile of the parasite and compared tubulin polymerization dynamics before and after the treatment using identified compounds. Last, in vivo anti-parasite activities of these compounds were determined in T. brucei-infected mice.Three compounds were selected that are 100 fold more effective against the growth of T. brucei cells than mammalian cells. These compounds caused cell cycle progression defects in T. brucei cells. Western analyses indicated that these compounds decreased tubulin polymerization in T. brucei cells. The in vivo investigation revealed that these compounds, when admitted orally, inhibited T. brucei cell proliferation in mouse blood. However, they were not potent enough to clear up the infection completely.These compounds are promising lead compounds as orally active agents for drug development of anti-trypanosome agents. A more detail structure activity relationship (SAR was summarized that will be used to guide future lead optimization to improve the selectivity and potency of the current compounds.

  6. Lineage-specific proteins essential for endocytosis in trypanosomes.

    Science.gov (United States)

    Manna, Paul T; Obado, Samson O; Boehm, Cordula; Gadelha, Catarina; Sali, Andrej; Chait, Brian T; Rout, Michael P; Field, Mark C

    2017-04-15

    Clathrin-mediated endocytosis (CME) is the most evolutionarily ancient endocytic mechanism known, and in many lineages the sole mechanism for internalisation. Significantly, in mammalian cells CME is responsible for the vast bulk of endocytic flux and has likely undergone multiple adaptations to accommodate specific requirements by individual species. In African trypanosomes, we previously demonstrated that CME is independent of the AP-2 adaptor protein complex, that orthologues to many of the animal and fungal CME protein cohort are absent, and that a novel, trypanosome-restricted protein cohort interacts with clathrin and drives CME. Here, we used a novel cryomilling affinity isolation strategy to preserve transient low-affinity interactions, giving the most comprehensive trypanosome clathrin interactome to date. We identified the trypanosome AP-1 complex, Trypanosoma brucei (Tb)EpsinR, several endosomal SNAREs plus orthologues of SMAP and the AP-2 associated kinase AAK1 as interacting with clathrin. Novel lineage-specific proteins were identified, which we designate TbCAP80 and TbCAP141. Their depletion produced extensive defects in endocytosis and endomembrane system organisation, revealing a novel molecular pathway subtending an early-branching and highly divergent form of CME, which is conserved and likely functionally important across the kinetoplastid parasites. © 2017. Published by The Company of Biologists Ltd.

  7. A function for a specific zinc metalloprotease of African trypanosomes.

    Directory of Open Access Journals (Sweden)

    Paul M Grandgenett

    2007-10-01

    Full Text Available The Trypanosoma brucei genome encodes three groups of zinc metalloproteases, each of which contains approximately 30% amino acid identity with the major surface protease (MSP, also called GP63 of Leishmania. One of these proteases, TbMSP-B, is encoded by four nearly identical, tandem genes transcribed in both bloodstream and procyclic trypanosomes. Earlier work showed that RNA interference against TbMSP-B prevents release of a recombinant variant surface glycoprotein (VSG from procyclic trypanosomes. Here, we used gene deletions to show that TbMSP-B and a phospholipase C (GPI-PLC act in concert to remove native VSG during differentiation of bloodstream trypanosomes to procyclic form. When the four tandem TbMSP-B genes were deleted from both chromosomal alleles, bloodstream B (-/- trypanosomes could still differentiate to procyclic form, but VSG was removed more slowly and in a non-truncated form compared to differentiation of wild-type organisms. Similarly, when both alleles of the single-copy GPI-PLC gene were deleted, bloodstream PLC (-/- cells could still differentiate. However, when all the genes for both TbMSP-B and GPI-PLC were deleted from the diploid genome, the bloodstream B (-/- PLC (-/- trypanosomes did not proliferate in the differentiation medium, and 60% of the VSG remained on the cell surface. Inhibitors of cysteine proteases did not affect this result. These findings demonstrate that removal of 60% of the VSG during differentiation from bloodstream to procyclic form is due to the synergistic activities of GPI-PLC and TbMSP-B.

  8. How to design and fly your humanly space object in space?

    Science.gov (United States)

    Balint, Tibor; Hall, Ashley

    2016-06-01

    Today's space exploration, both robotic- and human-exploration driven, is dominated by objects and artifacts which are mostly conceived, designed and built through technology and engineering approaches. They are functional, reliable, safe, and expensive. Building on considerations and concepts established in an earlier paper, we can state that the current approach leaves very little room for art and design based objects, as organizations-typically led by engineers, project and business managers-see the inclusion of these disciplines and artifacts as nice to have instead of a genuine need, let alone requirement. In this paper we will offer initial discussions about where design and engineering practices are different or similar and how to bridge them and highlight the benefits that domains such as design or art can offer to space exploration. Some of the design considerations and approaches will be demonstrated through the double diamond of divergence-convergence cycles of design, leading to an experimental piece called a "cybernetic astronaut chair", which was designed as a form of abstraction and discussion point to highlight a subset of concepts and ideas that designers may consider when designing objects for space use, with attention to human-centered or humanly interactions. Although there are few suggested functional needs for chairs in space, they can provide reassuring emotional experiences from home, while being far away from home. In zero gravity, back-to-back seats provide affordances-or add variety in a cybernetic sense-to accommodate two astronauts simultaneously, while implying the circularity of cybernetics in a rather symbolic way. The cybernetic astronaut chair allows us to refine the three-actor model proposed in a previous paper, defining the circular interactions between the artist or designer; object or process; and user or observer. We will also dedicate a brief discussion to the process of navigating through the complex regulations of space

  9. Phlebotomine sand flies (Diptera: Psychodidae) associated with changing patterns in the transmission of the human cutaneous leishmaniasis in French Guiana.

    Science.gov (United States)

    Fouque, Florence; Gaborit, Pascal; Issaly, Jean; Carinci, Romuald; Gantier, Jean-Charles; Ravel, Christophe; Dedet, Jean-Pierre

    2007-02-01

    Between March 2000 and December 2001 a survey of the sand flies (Diptera: Phlebotominae) of French Guiana was carried out during 14 nights of captures with CDC light-traps and Malaise traps, and resulted in the collection of 2245 individuals of 38 species. The most abundant species were Lutzomyia (Trichophoromyia) ininii Floch & Abonnenc, Lu.(Psychodopygus) squamiventris maripaensis Floch & Abonnenc, and Lu .(Nyssomyia) flaviscutellata Mangabeira. Half of the collected sand flies females were dissected under field conditions and five species were found harboring Leishmania-like parasites. The Leishmania (Kinetoplastidae: Trypanosomatidae) species were identified by molecular typing, and for the first time Lu. (Nys.) flaviscutellata was found harboring Leishmania (Viannia) guyanensis and Lu. (Tri) ininii harboring unknown Leishmania. The first record for French Guiana of Lu. (Psy.) squamiventris maripaensis harboring L. (V.) naiffi, was also reported. The patterns of diversification of the human cutaneous leishmaniasis transmission in French Guiana are discussed.

  10. Phlebotomine sand flies (Diptera: Psychodidae associated with changing patterns in the transmission of the human cutaneous leishmaniasis in French Guiana

    Directory of Open Access Journals (Sweden)

    Florence Fouque

    2007-02-01

    Full Text Available Between March 2000 and December 2001 a survey of the sand flies (Diptera: Phlebotominae of French Guiana was carried out during 14 nights of captures with CDC light-traps and Malaise traps, and resulted in the collection of 2245 individuals of 38 species. The most abundant species were Lutzomyia (Trichophoromyia ininii Floch & Abonnenc, Lu.(Psychodopygus squamiventris maripaensis Floch & Abonnenc, and Lu .(Nyssomyia flaviscutellata Mangabeira. Half of the collected sand flies females were dissected under field conditions and five species were found harboring Leishmania-like parasites. The Leishmania (Kinetoplastidae: Trypanosomatidae species were identified by molecular typing, and for the first time Lu. (Nys. flaviscutellata was found harboring Leishmania (Viannia guyanensis and Lu. (Tri ininii harboring unknown Leishmania. The first record for French Guiana of Lu. (Psy. squamiventris maripaensis harboring L. (V. naiffi, was also reported. The patterns of diversification of the human cutaneous leishmaniasis transmission in French Guiana are discussed.

  11. Molecular identification of blow flies recovered from human cadavers during crime scene investigations in Malaysia.

    Science.gov (United States)

    Kavitha, Rajagopal; Nazni, Wasi Ahmad; Tan, Tian Chye; Lee, Han Lim; Isa, Mohd Noor Mat; Azirun, Mohd Sofian

    2012-12-01

    Forensic entomology applies knowledge about insects associated with decedent in crime scene investigation. It is possible to calculate a minimum postmortem interval (PMI) by determining the age and species of the oldest blow fly larvae feeding on decedent. This study was conducted in Malaysia to identify maggot specimens collected during crime scene investigations. The usefulness of the molecular and morphological approach in species identifications was evaluated in 10 morphologically identified blow fly larvae sampled from 10 different crime scenes in Malaysia. The molecular identification method involved the sequencing of a total length of 2.2 kilo base pairs encompassing the 'barcode' fragments of the mitochondrial cytochrome oxidase I (COI), cytochrome oxidase II (COII) and t-RNA leucine genes. Phylogenetic analyses confirmed the presence of Chrysomya megacephala, Chrysomya rufifacies and Chrysomya nigripes. In addition, one unidentified blow fly species was found based on phylogenetic tree analysis.

  12. More than one rabbit out of the hat: Radiation, transgenic and symbiont-based approaches for sustainable management of mosquito and tsetse fly populations.

    Science.gov (United States)

    Bourtzis, Kostas; Lees, Rosemary Susan; Hendrichs, Jorge; Vreysen, Marc J B

    2016-05-01

    Mosquitoes (Diptera: Culicidae) and tsetse flies (Diptera: Glossinidae) are bloodsucking vectors of human and animal pathogens. Mosquito-borne diseases (malaria, filariasis, dengue, zika, and chikungunya) cause severe mortality and morbidity annually, and tsetse fly-borne diseases (African trypanosomes causing sleeping sickness in humans and nagana in livestock) cost Sub-Saharan Africa an estimated US$ 4750 million annually. Current reliance on insecticides for vector control is unsustainable: due to increasing insecticide resistance and growing concerns about health and environmental impacts of chemical control there is a growing need for novel, effective and safe biologically-based methods that are more sustainable. The integration of the sterile insect technique has proven successful to manage crop pests and disease vectors, particularly tsetse flies, and is likely to prove effective against mosquito vectors, particularly once sex-separation methods are improved. Transgenic and symbiont-based approaches are in development, and more advanced in (particularly Aedes) mosquitoes than in tsetse flies; however, issues around stability, sustainability and biosecurity have to be addressed, especially when considering population replacement approaches. Regulatory issues and those relating to intellectual property and economic cost of application must also be overcome. Standardised methods to assess insect quality are required to compare and predict efficacy of the different approaches. Different combinations of these three approaches could be integrated to maximise their benefits, and all have the potential to be used in tsetse and mosquito area-wide integrated pest management programmes.

  13. In vitro activity of 2-pyridinecarboxylic acid against trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus - doi: 10.4025/actascibiolsci.v33i4.6482 In vitro activity of 2-pyridinecarboxylic acid against trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus - doi: 10.4025/actascibiolsci.v33i4.6482

    Directory of Open Access Journals (Sweden)

    Sueli Fumie Yamada-Ogatta

    2011-09-01

    Full Text Available The effect of 2-pyridinecarboxylic acid (picolinic acid on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 µg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 µg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was 275 µg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a competitive inhibition. Furthermore, two anti-Trypanosoma (Schizotrypanum cruzi drugs were also evaluated with regard to bat trypanosome growth. Benznidazole, at 50 µg mL-1, inhibited epimastigote growth by 90% after 12 days incubation. Nifurtimox, at the same concentration, caused 96% growth inhibition after four days incubation. Corroborating a previous study, bat trypanosomes are a good model for screening new trypanocidal compounds. Moreover, they can be used to study many biological processes common to human pathogenic trypanosomatids.The effect of 2-pyridinecarboxylic acid (picolinic acid on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 µg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 µg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was 275 µg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a

  14. Database Description - Trypanosomes Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us Trypanosomes Database... Database Description General information of database Database name Trypanosomes Database...rmation and Systems Yata 1111, Mishima, Shizuoka 411-8540, JAPAN E mail: Database... classification Protein sequence databases Organism Taxonomy Name: Trypanosoma Taxonomy ID: 5690 Taxonomy Na...me: Homo sapiens Taxonomy ID: 9606 Database description The Trypanosomes database is a database providing th

  15. ASSOCIATION OF TRYPANOSOME INFECTION WITH SPERM ANTIBODIES PRODUCTION IN RED SOKOTO (MARADI GOATS

    Directory of Open Access Journals (Sweden)

    O. FAYEMI

    2006-01-01

    Full Text Available A total of 1021 randomly selected serum samples of adult male goats that had been screened for trypanosome infection were assayed for sperm antibodies using the immunoperoxidase staining technique. The result of the trypanosome screening revealed that 586(57.39% goats were positive for trypanosome infection, while 435(42.61% were negative. The assay for sperm antibodies showed that 482(47.21% animals were positive, while 539(52.79% were negative. In the group that was positive for trypanosome infection, 364(62.12% animals were positive, whereas 222(37.88% were negative for sperm antibodies (P<0.001. The group that was negative for trypanosome infection, had a significantly lower number and proportion 118(27.13% of positive compared to 317(72.87% negative for sperm antibodies. Out of a total 482 goats that were positive for sperm antibodies, a significantly higher number, 364(75.52%, were positive than 118(24.48% that were negative for trypanosome infection (P<0.001. In the group that was found negative for sperm antibodies, a significantly lower proportion, 222(41.19%, was positive compared to 317(58.81% that were negative for trypanosome infection (P<0.001. Seropositivity to sperm antibodies was positively correlated to trypanosome infection (P<0.001. Further work on the pathogenesis of sperm antibody production in trypanosome infection is advocated.

  16. Update History of This Database - Trypanosomes Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us Trypanosomes Database Update History of This Database Date Update contents 2014/05/07 The co...ntact information is corrected. The features and manner of utilization of the database are corrected. 2014/02/04 Trypanosomes Databas...e English archive site is opened. 2011/04/04 Trypanosomes Database ( http://www.tan...paku.org/tdb/ ) is opened. About This Database Database Description Download Lice...nse Update History of This Database Site Policy | Contact Us Update History of This Database - Trypanosomes Database | LSDB Archive ...

  17. An annotated checklist of the horse flies, deer flies, and yellow flies (Diptera: Tabanidae) of Florida

    Science.gov (United States)

    The family Tabanidae includes the horse flies, deer flies, and yellow flies and is considered a significant pest of livestock throughout the United States, including Florida. Tabanids can easily become a major pest of man, especially salt marsh species which are known to readily feed on humans and o...

  18. Tsetse flies: their biology and control using area-wide integrated pest management approaches.

    Science.gov (United States)

    Vreysen, Marc J B; Seck, Momar Talla; Sall, Baba; Bouyer, Jérémy

    2013-03-01

    Tsetse flies are the cyclical vectors of trypanosomes, the causative agents of 'sleeping sickness' or human African trypanosomosis (HAT) in humans and 'nagana' or African animal trypanosomosis (AAT) in livestock in Sub-saharan Africa. Many consider HAT as one of the major neglected tropical diseases and AAT as the single greatest health constraint to increased livestock production. This review provides some background information on the taxonomy of tsetse flies, their unique way of reproduction (adenotrophic viviparity) making the adult stage the only one easily accessible for control, and how their ecological affinities, their distribution and population dynamics influence and dictate control efforts. The paper likewise reviews four control tactics (sequential aerosol technique, stationary attractive devices, live bait technique and the sterile insect technique) that are currently accepted as friendly to the environment, and describes their limitations and advantages and how they can best be put to practise in an IPM context. The paper discusses the different strategies for tsetse control i.e. localised versus area-wide and focusses thereafter on the principles of area-wide integrated pest management (AW-IPM) and the phased-conditional approach with the tsetse project in Senegal as a recent example. We argue that sustainable tsetse-free zones can be created on Africa mainland provided certain managerial and technical prerequisites are in place.

  19. The morphology of fecal and regurgitation artifacts deposited by the blow fly Lucilia cuprina fed a diet of human blood.

    Science.gov (United States)

    Durdle, Annalisa; van Oorschot, Roland A H; Mitchell, R John

    2013-07-01

    Fly feces and regurgitation deposits may be mistaken for bloodstain patterns at a crime scene, potentially compromising event reconstruction and/or misdirecting police resources. In some instances, these artifacts contain sufficient human biological material to generate a full DNA profile, sometimes 2 years after deposition. Clearly, it is important that investigators can make the distinction between artifacts and bloodstains. This study examined 6645 artifacts deposited on a smooth, nonporous surface after Lucilia cuprina were fed human blood. Artifacts were also compared with bloodstains on a variety of other surfaces. Both similarities and differences were found between artifacts and bloodstains, highlighting the need for an identification system to assist personnel with little training in bloodstain pattern analysis. The morphology of the artifacts has been described so that these deposits may be more clearly distinguished from bloodstains, targeted by crime scene personnel as potential sources of human DNA, and/or identified as potential evidence contaminants. Flowcharts have been devised to facilitate the analysis.

  20. Flying Things

    DEFF Research Database (Denmark)

    Cermak, Daniel

    2016-01-01

    Daniel Cermak-Sassenrath. Flying Things. Installation. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016.......Daniel Cermak-Sassenrath. Flying Things. Installation. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016....

  1. First detection of Leishmania tropica DNA and Trypanosoma species in Sergentomyia sand flies (Diptera: Psychodidae) from an outbreak area of cutaneous leishmaniasis in Ghana.

    Science.gov (United States)

    Nzelu, Chukwunonso O; Kato, Hirotomo; Puplampu, Naiki; Desewu, Kwame; Odoom, Shirley; Wilson, Michael D; Sakurai, Tatsuya; Katakura, Ken; Boakye, Daniel A

    2014-02-01

    Leishmania major and an uncharacterized species have been reported from human patients in a cutaneous leishmaniasis (CL) outbreak area in Ghana. Reports from the area indicate the presence of anthropophilic Sergentomyia species that were found with Leishmania DNA. In this study, we analyzed the Leishmania DNA positive sand fly pools by PCR-RFLP and ITS1 gene sequencing. The trypanosome was determined using the SSU rRNA gene sequence. We observed DNA of L. major, L. tropica and Trypanosoma species to be associated with the sand fly infections. This study provides the first detection of L. tropica DNA and Trypanosoma species as well as the confirmation of L. major DNA within Sergentomyia sand flies in Ghana and suggests that S. ingrami and S. hamoni are possible vectors of CL in the study area. The detection of L. tropica DNA in this CL focus is a novel finding in Ghana as well as West Africa. In addition, the unexpected infection of Trypanosoma DNA within S. africana africana indicates that more attention is necessary when identifying parasitic organisms by PCR within sand fly vectors in Ghana and other areas where leishmaniasis is endemic.

  2. First detection of Leishmania tropica DNA and Trypanosoma species in Sergentomyia sand flies (Diptera: Psychodidae from an outbreak area of cutaneous leishmaniasis in Ghana.

    Directory of Open Access Journals (Sweden)

    Chukwunonso O Nzelu

    2014-02-01

    Full Text Available BACKGROUND: Leishmania major and an uncharacterized species have been reported from human patients in a cutaneous leishmaniasis (CL outbreak area in Ghana. Reports from the area indicate the presence of anthropophilic Sergentomyia species that were found with Leishmania DNA. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we analyzed the Leishmania DNA positive sand fly pools by PCR-RFLP and ITS1 gene sequencing. The trypanosome was determined using the SSU rRNA gene sequence. We observed DNA of L. major, L. tropica and Trypanosoma species to be associated with the sand fly infections. This study provides the first detection of L. tropica DNA and Trypanosoma species as well as the confirmation of L. major DNA within Sergentomyia sand flies in Ghana and suggests that S. ingrami and S. hamoni are possible vectors of CL in the study area. CONCLUSIONS/SIGNIFICANCE: The detection of L. tropica DNA in this CL focus is a novel finding in Ghana as well as West Africa. In addition, the unexpected infection of Trypanosoma DNA within S. africana africana indicates that more attention is necessary when identifying parasitic organisms by PCR within sand fly vectors in Ghana and other areas where leishmaniasis is endemic.

  3. Horizontally Transferred Genetic Elements in the Tsetse Fly Genome: An Alignment-Free Clustering Approach Using Batch Learning Self-Organising Map (BLSOM)

    Science.gov (United States)

    Nakao, Ryo; Funayama, Shunsuke

    2016-01-01

    Tsetse flies (Glossina spp.) are the primary vectors of trypanosomes, which can cause human and animal African trypanosomiasis in Sub-Saharan African countries. The objective of this study was to explore the genome of Glossina morsitans morsitans for evidence of horizontal gene transfer (HGT) from microorganisms. We employed an alignment-free clustering method, that is, batch learning self-organising map (BLSOM), in which sequence fragments are clustered based on the similarity of oligonucleotide frequencies independently of sequence homology. After an initial scan of HGT events using BLSOM, we identified 3.8% of the tsetse fly genome as HGT candidates. The predicted donors of these HGT candidates included known symbionts, such as Wolbachia, as well as bacteria that have not previously been associated with the tsetse fly. We detected HGT candidates from diverse bacteria such as Bacillus and Flavobacteria, suggesting a past association between these taxa. Functional annotation revealed that the HGT candidates encoded loci in various functional pathways, such as metabolic and antibiotic biosynthesis pathways. These findings provide a basis for understanding the coevolutionary history of the tsetse fly and its microbes and establish the effectiveness of BLSOM for the detection of HGT events. PMID:28074180

  4. Sexual differences in prevalence of a new species of trypanosome infecting túngara frogs

    Directory of Open Access Journals (Sweden)

    Ximena E. Bernal

    2016-04-01

    Full Text Available Trypanosomes are a diverse group of protozoan parasites of vertebrates transmitted by a variety of hematophagous invertebrate vectors. Anuran trypanosomes and their vectors have received relatively little attention even though these parasites have been reported from frog and toad species worldwide. Blood samples collected from túngara frogs (Engystomops pustulosus, a Neotropical anuran species heavily preyed upon by eavesdropping frog-biting midges (Corethrella spp., were examined for trypanosomes. Our results revealed sexual differences in trypanosome prevalence with female frogs being rarely infected (<1%. This finding suggests this protozoan parasite may be transmitted by frog-biting midges that find their host using the mating calls produced by male frogs. Following previous anuran trypanosome studies, we examined 18S ribosomal RNA gene to characterize and establish the phylogenetic relationship of the trypanosome species found in túngara frogs. A new species of giant trypanosome, Trypanosoma tungarae n. sp., is described in this study. Overall the morphometric data revealed that the trypomastigotes of T. tungarae n. sp. are similar to other giant trypanosomes such as Trypanosoma rotatorium and Trypanosoma ranarum. Despite its slender and long cell shape, however, 18S rRNA gene sequences revealed that T. tungarae n. sp. is sister to the rounded-bodied giant trypanosome, Trypanosoma chattoni. Therefore, morphological convergence explains similar morphology among members of two non-closely related groups of trypanosomes infecting frogs. The results from this study underscore the value of coupling morphological identification with molecular characterization of anuran trypanosomes.

  5. Depravity and Pessimism in the Twentieth Century:Darkness of Human Nature in Lord of the Flies

    Institute of Scientific and Technical Information of China (English)

    赵秋楠

    2015-01-01

    The WWⅡhad a great influence on the people all over the world.People in different ways were expressing their anger.William Golding‘s Lord of the Flies expressed the darkness of human nature after the war.Through the individual symbols, both depravity&pessimism in the twentieth century and darkness of human nature in Lord of the Flies could be well understood.%第二次世界大战给全世界的人们带来了极大的影响,人们也不同的方式来抒发不满。威廉戈尔丁的《蝇王》则抒发了战后人性的黑暗。通过个体象征的运用,20世纪的堕落与悲观主义和《蝇王》中的人性黑暗面得到了很好地理解。

  6. Evolution of the serum resistance-associated SRA gene in African trypanosomes

    Institute of Scientific and Technical Information of China (English)

    LAI DeHua; WANG QiaoPing; LI Zhi; JULIUS Luke(s); LUN ZhaoRong

    2009-01-01

    Serum resistance-associated (SRA) protein, a protein unique for Trypanosoma brucei rhodesiense, is responsible for resistance of this parasite to the lysis by normal human serum (NHS) and is a vital molecular marker to distinguish this species from other African trypanosomes. We cloned and se-quenced the SRA basic copy (SRAbc) gene from T. b. rhodesiense and related species and found that this gene is confined to the subgenus Trypanozoon. The average 82% identity among the sequenced SRAbc genes indicates that they may have a common origin and are highly conserved. Since SRAbc coexists in the T. b. rhodesiense genome with SRA, we propose that SRAbc might be the 'donor VSG', which after duplication became inserted into the expression site by recombination. Under natural se-lection, SRAbc could reform into SRA following mosaic formation.

  7. The interaction between nutrition and metabolism in West African Dwarf goats, infected with trypanosomes.

    NARCIS (Netherlands)

    Dam, van J.T.P.

    1996-01-01

    In a series of experiments the interaction between nutrition and energy- and nitrogen metabolism of West African Dwarf goats, infected with trypanosomes was studied. Animals were injected with trypanosomes, and feed intake, energy and nitrogen balance and blood metabolites and hormones were measured

  8. Rediscovery of Trypanosoma (Pycnomonas) suis, a tsetse-transmitted trypanosome closely related to T. brucei.

    Science.gov (United States)

    Hutchinson, Rachel; Gibson, Wendy

    2015-12-01

    The African tsetse-transmitted trypanosomes are considered to be a well-known group of parasitic protozoa, but in 2008 a novel and distinctive trypanosome related to Trypanosoma brucei was discovered among tsetse isolates from Msubugwe in Tanzania. The host range, distribution and potential pathogenicity of this new trypanosome remain to be elucidated; such studies would be facilitated by a sensitive and specific identification method. Here, we identified two highly repetitive elements in the genome of the new trypanosome: a 177 bp repeat, which was located predominantly on the highly abundant minichromosomes, and a 138 bp repeat, which was widely dispersed in the genome. A PCR test based on each repeat was specific for the new trypanosome and sensitive to Trypanosoma (Pycnomonas) suis. We also present data on the molecular karyotype and spliced leader (SL, miniexon) repeat of the new trypanosome, both of which distinguish T. suis from other, better-known African tsetse-transmitted trypanosomes. The rediscovery of T. suis opens new lines of research into the evolution and biology of the African trypanosomes.

  9. The interaction between nutrition and metabolism in West African dwarf goats, infected with trypanosomes

    NARCIS (Netherlands)

    Dam, van J.T.P.

    1996-01-01

    In a series of experiments the interaction between nutrition and energy- and nitrogen metabolism of West African Dwarf goats, infected with trypanosomes was studied. Animals were injected with trypanosomes, and feed intake, energy and nitrogen balance and blood metabolites and hormones were measured

  10. License - Trypanosomes Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us Trypanosomes Database License License to Use This Database Last updated : 2014/02/04 You may use this database...pecifies the license terms regarding the use of this database and the requirements you must follow in using this database.... The license for this database is specified in the Creative Commons... Attribution-Share Alike 2.1 Japan . If you use data from this database, please be sure attribute this database...pan is found here . With regard to this database, you are licensed to: freely access part or whole of this database

  11. The interaction of fish trypanosome culture forms with some lectins.

    Science.gov (United States)

    Zajícek, P; Pecková, H

    1990-01-01

    The interactions of fish trypanosome culture forms with 11 purified lectins were compared using the agglutination test in microwell plates. Altogether, ten stocks of ten different freshwater fish species were examined. Three basic types of cell-lectin interactions were observed on the microscopical level. The strong agglutination of all stocks regardless their original host was found in the presence of Con A, PSA, RCA60, and RCA120, which implies the presence of relatively high amounts of sugar residues of D-mannose and D-galactose in the surface of culture forms of these parasites. Weak agglutinations of some stocks were observed in the presence of LCA, PNA, SBA, and WGA lectins, but their low intensity makes them not sufficiently reliable for stock characterization. The lectins UEA I, HPA, and PHA caused no agglutination. In conclusion, in case of unequivocal results no remarkable differences in the interactions of various stocks of trypanosomes culture forms with used lectins were observed. These results imply the high degree of similarity of their main cell surface saccharide structures.

  12. Homology modeling of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABA receptor channels and Surflex-docking of fipronil.

    Science.gov (United States)

    Cheng, Jin; Ju, Xiu-Lian; Chen, Xiang-Yang; Liu, Gen-Yan

    2009-09-01

    To further explore the mechanism of selective binding of the representative gamma-aminobutyric acid receptors (GABARs) noncompetitive antagonist (NCA) fipronil to insect over mammalian GABARs, three-dimensional models of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABAR were generated by homology modeling, using the cryo-electron microscopy structure of the nicotinic acetylcholine receptor (nAChR) of Torpedo marmorata as a template. Fipronil was docked into the putative binding site of the human alpha 1 beta 2 gamma 2 and house fly beta 3 receptors by Surflex-docking, and the calculated docking energies are in agreement with experimental results. The GABA receptor antagonist fipronil exhibited higher potency with house fly beta 3 GABAR than with human alpha 1 beta 2 gamma 2 GABAR. Furthermore, analyses of Surflex-docking suggest that the H-bond interaction of fipronil with Ala2 and Thr6 in the second transmembrane segment (TM2) of these GABARs plays a relatively important role in ligand selective binding. The different subunit assemblies of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABARs may result in differential selectivity for fipronil.

  13. Flying Scared

    DEFF Research Database (Denmark)

    Dal Sie, Marco; Josiassen, Alexander

    service quality expectations and fear of flying affect travellers' flight choices on long-haul flights. The study was set in Bangkok and primary data were obtained from a large sample of travelers departing from Suvarnabhumi Airport. While service quality emerged as a relevant factor, fear of flying didn......’t turn out as a variable affecting travellers’ choices....

  14. Regulatory RNAs and chromatin modification in dosage compensation: A continuous path from flies to humans?

    Directory of Open Access Journals (Sweden)

    Lavranos Giagkos

    2008-03-01

    Full Text Available Abstract Chromosomal sex determination is a widely distributed strategy in nature. In the most classic scenario, one sex is characterized by a homologue pair of sex chromosomes, while the other includes two morphologically and functionally distinct gonosomes. In mammalian diploid cells, the female is characterized by the presence of two identical X chromosomes, while the male features an XY pair, with the Y bearing the major genetic determinant of sex, i.e. the SRY gene. In other species, such as the fruitfly, sex is determined by the ratio of autosomes to X chromosomes. Regardless of the exact mechanism, however, all these animals would exhibit a sex-specific gene expression inequality, due to the different number of X chromosomes, a phenomenon inhibited by a series of genetic and epigenetic regulatory events described as "dosage compensation". Since adequate available data is currently restricted to worms, flies and mammals, while for other groups of animals, such as reptiles, fish and birds it is very limited, it is not yet clear whether this is an evolutionary conserved mechanism. However certain striking similarities have already been observed among evolutionary distant species, such as Drosophila melanogaster and Mus musculus. These mainly refer to a the need for a counting mechanism, to determine the chromosomal content of the cell, i.e. the ratio of autosomes to gonosomes (a process well understood in flies, but still hypothesized in mammals, b the implication of non-translated, sex-specific, regulatory RNAs (roX and Xist, respectively as key elements in this process and the location of similar mediators in the Z chromosome of chicken c the inclusion of a chromatin modification epigenetic final step, which ensures that gene expression remains stably regulated throughout the affected area of the gonosome. This review summarizes these points and proposes a possible role for comparative genetics, as they seem to constitute proof of

  15. Characterization of human gene encoding SLA/LP autoantigen and its conserved homologs in mouse,fish,fly,and worm

    Institute of Scientific and Technical Information of China (English)

    Chun-Xia Wang; Andreas Teufel; Uta Cheruti; Joachim Gr(o)tzinger; Peter R Galle; Ansgar W Lohse; Johannes Herkel

    2006-01-01

    AIM: To approach the elusive function of the SLA/LP molecule, we have characterized genomic organization and conservation of the major antigenic and functional properties of the SLA/LP molecule in various species.METHODS: By means of computational biology, we have characterized the complete SLA/LP gene, mRNA and deduced protein sequences in man, mouse,zebrafish, fly, and worm.RESULTS: The human SLA/LP gene sequence of approximately 39 kb, which maps to chromosome 4p15.2, is organized in 11 exons, of which 10 or 11 are translated, depending on the splice variant. Homologous molecules were identified in several biological model organisms. The various homologous protein sequences showed a high degree of similarity or homology, notably at those residues that are of functional importance. The only domain of the human protein sequence that lacks significant homology with homologous sequences is the major antigenic epitope recognized by autoantibodies from autoimmune hepatitis (AIH) patients.CONCLUSION: The SLA/LP molecule and its functionally relevant residues have been highly conserved throughout the evoluti n, suggesting an indispensable function of the molecule. The finding that the only non-conserved domain is the dominant antigenic epitope of the human SLA/LP sequence, suggests that SLA/LP autoimmunity is autoantigen-driven rather than being driven by molecular mimicry.

  16. Differential trypanosome surface coat regulation by a CCCH protein that co-associates with procyclin mRNA cis-elements.

    Directory of Open Access Journals (Sweden)

    Pegine Walrad

    2009-02-01

    Full Text Available The genome of Trypanosoma brucei is unusual in being regulated almost entirely at the post-transcriptional level. In terms of regulation, the best-studied genes are procyclins, which encode a family of major surface GPI-anchored glycoproteins (EP1, EP2, EP3, GPEET that show differential expression in the parasite's tsetse-fly vector. Although procyclin mRNA cis-regulatory sequences have provided the paradigm for post-transcriptional control in kinetoplastid parasites, trans-acting regulators of procyclin mRNAs are unidentified, despite intensive effort over 15 years. Here we identify the developmental regulator, TbZFP3, a CCCH-class predicted RNA binding protein, as an isoform-specific regulator of Procyclin surface coat expression in trypanosomes. We demonstrate (i that endogenous TbZFP3 shows sequence-specific co-precipitation of EP1 and GPEET, but not EP2 and EP3, procyclin mRNA isoforms, (ii that ectopic overexpression of TbZFP3 does not perturb the mRNA abundance of procyclin transcripts, but rather that (iii their protein expression is regulated in an isoform-specific manner, as evidenced by mass spectrometric analysis of the Procyclin expression signature in the transgenic cell lines. The TbZFP3 mRNA-protein complex (TbZFP3mRNP is identified as a trans-regulator of differential surface protein expression in trypanosomes. Moreover, its sequence-specific interactions with procyclin mRNAs are compatible with long-established predictions for Procyclin regulation. Combined with the known association of TbZFP3 with the translational apparatus, this study provides a long-sought missing link between surface protein cis-regulatory signals and the gene expression machinery in trypanosomes.

  17. Flies (Calliphoridae, Muscidae and Beetles (Silphidae from Human Cadavers in Cali, Colombia

    Directory of Open Access Journals (Sweden)

    Barreto Mauricio

    2002-01-01

    Full Text Available Adult specimens of Cochliomyia macellaria, Chrysomya megacephala, Ch. rufifacies, Lucilia sp. (Calliphoridae, Musca domestica (Muscidae, Oxelytrum discicolle (Silphidae and Sarcophagidae were recovered from 12 human cadavers in Cali, Valle, Colombia. Information regarding these findings is presented.

  18. A Receptor-Based Explanation for Tsetse Fly Catch Distribution between Coloured Cloth Panels and Flanking Nets.

    Science.gov (United States)

    Santer, Roger D

    2015-01-01

    Tsetse flies transmit trypanosomes that cause nagana in cattle, and sleeping sickness in humans. Therefore, optimising visual baits to control tsetse is an important priority. Tsetse are intercepted at visual baits due to their initial attraction to the bait, and their subsequent contact with it due to landing or accidental collision. Attraction is proposed to be driven in part by a chromatic mechanism to which a UV-blue photoreceptor contributes positively, and a UV and a green photoreceptor contribute negatively. Landing responses are elicited by stimuli with low luminance, but many studies also find apparently strong landing responses when stimuli have high UV reflectivity, which would imply that UV wavelengths contribute negatively to attraction at a distance, but positively to landing responses at close range. The strength of landing responses is often judged using the number of tsetse sampled at a cloth panel expressed as a proportion of the combined catch of the cloth panel and a flanking net that samples circling flies. I modelled these data from two previously published field studies, using calculated fly photoreceptor excitations as predictors. I found that the proportion of tsetse caught on the cloth panel increased with an index representing the chromatic mechanism driving attraction, as would be expected if the same mechanism underlay both long- and close-range attraction. However, the proportion of tsetse caught on the cloth panel also increased with excitation of the UV-sensitive R7p photoreceptor, in an apparently separate but interacting behavioural mechanism. This R7p-driven effect resembles the fly open-space response which is believed to underlie their dispersal towards areas of open sky. As such, the proportion of tsetse that contact a cloth panel likely reflects a combination of deliberate landings by potentially host-seeking tsetse, and accidental collisions by those seeking to disperse, with a separate visual mechanism underlying each

  19. A Receptor-Based Explanation for Tsetse Fly Catch Distribution between Coloured Cloth Panels and Flanking Nets.

    Directory of Open Access Journals (Sweden)

    Roger D Santer

    Full Text Available Tsetse flies transmit trypanosomes that cause nagana in cattle, and sleeping sickness in humans. Therefore, optimising visual baits to control tsetse is an important priority. Tsetse are intercepted at visual baits due to their initial attraction to the bait, and their subsequent contact with it due to landing or accidental collision. Attraction is proposed to be driven in part by a chromatic mechanism to which a UV-blue photoreceptor contributes positively, and a UV and a green photoreceptor contribute negatively. Landing responses are elicited by stimuli with low luminance, but many studies also find apparently strong landing responses when stimuli have high UV reflectivity, which would imply that UV wavelengths contribute negatively to attraction at a distance, but positively to landing responses at close range. The strength of landing responses is often judged using the number of tsetse sampled at a cloth panel expressed as a proportion of the combined catch of the cloth panel and a flanking net that samples circling flies. I modelled these data from two previously published field studies, using calculated fly photoreceptor excitations as predictors. I found that the proportion of tsetse caught on the cloth panel increased with an index representing the chromatic mechanism driving attraction, as would be expected if the same mechanism underlay both long- and close-range attraction. However, the proportion of tsetse caught on the cloth panel also increased with excitation of the UV-sensitive R7p photoreceptor, in an apparently separate but interacting behavioural mechanism. This R7p-driven effect resembles the fly open-space response which is believed to underlie their dispersal towards areas of open sky. As such, the proportion of tsetse that contact a cloth panel likely reflects a combination of deliberate landings by potentially host-seeking tsetse, and accidental collisions by those seeking to disperse, with a separate visual mechanism

  20. The diamidine diminazene aceturate is a substrate for the high-affinity pentamidine transporter: implications for the development of high resistance levels in trypanosomes.

    Science.gov (United States)

    Teka, Ibrahim A; Kazibwe, Anne J N; El-Sabbagh, Nasser; Al-Salabi, Mohammed I; Ward, Christopher P; Eze, Anthonius A; Munday, Jane C; Mäser, Pascal; Matovu, Enock; Barrett, Michael P; de Koning, Harry P

    2011-07-01

    African trypanosomiasis is a disease of humans and livestock in many areas south of the Sahara. Resistance to the few existing drugs is a major impediment to the control of these diseases, and we investigated how resistance to the main veterinary drug diminazene aceturate correlates with changes in drug transport in resistant strains. The strain tbat1(-/-), lacking the TbAT1/P2 aminopurine transporter implicated previously in diminazene transport, was adapted to higher levels of diminazene resistance. The resulting cell line was designated ABR and was highly cross-resistant to other diamidines and moderately resistant to cymelarsan. Procyclic trypanosomes were shown to be a convenient model to study diamidine uptake in Trypanosoma brucei brucei given the lack of TbAT1/P2 and a 10-fold higher activity of the high-affinity pentamidine transporter (HAPT1). Diminazene could be transported by HAPT1 in procyclic trypanosomes. This drug transport activity was lacking in the ABR line, as reported previously for the pentamidine-adapted line B48. The K(m) for diminazene transport in bloodstream tbat1(-/-) trypanosomes was consistent with uptake by HAPT1. Diminazene transport in ABR and B48 cells was reduced compared with tbat1(-/-), but their resistance phenotype was different: B48 displayed higher levels of resistance to pentamidine and the melaminophenyl arsenicals, whereas ABR displayed higher resistance to diminazene. These results establish a loss of HAPT1 function as a contributing factor to diminazene resistance but equally demonstrate for the first time that adaptations other than those determining the initial rates of drug uptake contribute to diamidine and arsenical resistance in African trypanosomes.

  1. Updating the salivary gland transcriptome of Phlebotomus papatasi (Tunisian strain: the search for sand fly-secreted immunogenic proteins for humans.

    Directory of Open Access Journals (Sweden)

    Maha Abdeladhim

    Full Text Available INTRODUCTION: Sand fly saliva plays an important role in both blood feeding and outcome of Leishmania infection. A cellular immune response against a Phlebotomus papatasi salivary protein was shown to protect rodents against Leishmania major infection. In humans, P. papatasi salivary proteins induce a systemic cellular immune response as well as a specific antisaliva humoral immune response, making these salivary proteins attractive targets as markers of exposure for this Leishmania vector. Surprisingly, the repertoire of salivary proteins reported for P. papatasi-a model sand fly for Leishmania-vector-host molecular interactions-is very limited compared with other sand fly species. We hypothesize that a more comprehensive study of the transcripts present in the salivary glands of P. papatasi will provide better knowledge of the repertoire of proteins of this important vector and will aid in selection of potential immunogenic proteins for humans and of those proteins that are highly conserved between different sand fly strains. METHODS AND FINDINGS: A cDNA library from P. papatasi (Tunisian strain salivary glands was constructed, and randomly selected transcripts were sequenced and analyzed. The most abundant transcripts encoding secreted proteins were identified and compared with previously reported sequences. Importantly, we identified salivary proteins not described before in this sand fly species. CONCLUSIONS: Comparative analysis between the salivary proteins of P. papatasi from Tunisia and Israel strains shows a high level of identity, suggesting these proteins as potential common targets for markers of vector exposure or inducers of cellular immune responses in humans for different geographic areas.

  2. Epidemiological aspects of bovine trypanosomosis in an endemic focus of eastern Zambia: The role of trypanosome strain variability in disease pattern

    Directory of Open Access Journals (Sweden)

    Justin Masumu

    2012-06-01

    Full Text Available Bovine trypanosomosis displays various epidemiological aspects in various areas. In some instances the disease has a high prevalence in animals with high impact on production whereas in other cases the disease has a low impact on production despite a high level of infection in animals. In addition epidemiological changes are frequently observed in various areas and are related to many factors including the vectors, the host, the parasites, the environment as well as the livestock management. However the implication of these factors in these changes is not fully elucidated. In eastern Zambia, factors predicting the establishment of severe infection in cattle are all present. However trypanosomosis occurring in cattle in this area has a low impact on livestock production. Several studies on the characterisation of trypanosome strains circulating in domestic and wild animals have been conducted in order to clarify the epidemiology of this disease in this area. These studies aimed at evaluating genetic and biological characteristics of these strains including their virulence profiles, their transmissibility by tsetse flies, their resistance to drugs and interference between different strains. In this review these findings are analysed in order to elucidate the implication of trypanosome strain variability in the distribution and the expression of this disease in the study area. The evolutionary trends of the situation occurring in this study area are also explained. Use of these findings is the context of disease control in the study area is further discussed.

  3. Infections with immunogenic trypanosomes reduce tsetse reproductive fitness: potential impact of different parasite strains on vector population structure.

    Directory of Open Access Journals (Sweden)

    Changyun Hu

    Full Text Available The parasite Trypanosoma brucei rhodesiense and its insect vector Glossina morsitans morsitans were used to evaluate the effect of parasite clearance (resistance as well as the cost of midgut infections on tsetse host fitness. Tsetse flies are viviparous and have a low reproductive capacity, giving birth to only 6-8 progeny during their lifetime. Thus, small perturbations to their reproductive fitness can have a major impact on population densities. We measured the fecundity (number of larval progeny deposited and mortality in parasite-resistant tsetse females and untreated controls and found no differences. There was, however, a typanosome-specific impact on midgut infections. Infections with an immunogenic parasite line that resulted in prolonged activation of the tsetse immune system delayed intrauterine larval development resulting in the production of fewer progeny over the fly's lifetime. In contrast, parasitism with a second line that failed to activate the immune system did not impose a fecundity cost. Coinfections favored the establishment of the immunogenic parasites in the midgut. We show that a decrease in the synthesis of Glossina Milk gland protein (GmmMgp, a major female accessory gland protein associated with larvagenesis, likely contributed to the reproductive lag observed in infected flies. Mathematical analysis of our empirical results indicated that infection with the immunogenic trypanosomes reduced tsetse fecundity by 30% relative to infections with the non-immunogenic strain. We estimate that a moderate infection prevalence of about 26% with immunogenic parasites has the potential to reduce tsetse populations. Potential repercussions for vector population growth, parasite-host coevolution, and disease prevalence are discussed.

  4. Bacteria, Yeast, Worms, and Flies: Exploiting Simple Model Organisms to Investigate Human Mitochondrial Diseases

    Science.gov (United States)

    Rea, Shane L.; Graham, Brett H.; Nakamaru-Ogiso, Eiko; Kar, Adwitiya; Falk, Marni J.

    2010-01-01

    The extensive conservation of mitochondrial structure, composition, and function across evolution offers a unique opportunity to expand our understanding of human mitochondrial biology and disease. By investigating the biology of much simpler model organisms, it is often possible to answer questions that are unreachable at the clinical level.…

  5. Bacteria, Yeast, Worms, and Flies: Exploiting Simple Model Organisms to Investigate Human Mitochondrial Diseases

    Science.gov (United States)

    Rea, Shane L.; Graham, Brett H.; Nakamaru-Ogiso, Eiko; Kar, Adwitiya; Falk, Marni J.

    2010-01-01

    The extensive conservation of mitochondrial structure, composition, and function across evolution offers a unique opportunity to expand our understanding of human mitochondrial biology and disease. By investigating the biology of much simpler model organisms, it is often possible to answer questions that are unreachable at the clinical level.…

  6. Pollen recovered from the exoskeleton of stable flies, Stomoxys calcitrans (L.) in Gainesville, Florida

    Science.gov (United States)

    Stable flies are pestiferous blood feeding flies that attack animals and humans. Besides consuming blood, these flies will also visit flowers to take nectar meals. When feeding on nectar, flies become coated with pollen which can be used to identify flowers used by the flies. Recently, flies cove...

  7. Time flies

    DEFF Research Database (Denmark)

    Wit, Janneke

    , the LS fly might be able to spend energy more generously on different tasks. Therefor, the capacity of LS and C lines to locate resources in a natural environment was tested. It turns out that LS flies are less likely to find food than C flies in such a setting, yet that as they age, their ability...... to locate food decreases slower than that of C lines. Gene expression of 10 candidate genes for longevity was quantified in two types of C and LS lines at three different ages. One of these genes, CG32638, indeed appears to be involved in life span determination in both males and females, regardless...... of mating status. Generalising studies on ageing in D. melanogaster can be cumbersome, especially in light of discrepancy between correlated responses between studies. To elucidate which mechanisms might be conserved due to evolutionary constraints, life span of 13 species of Drosophila was determined...

  8. Black flies (Diptera : Simuliidae attracted to humans and water buffalos and natural infections with filarial larvae, probably Onchocerca sp., in northern Thailand

    Directory of Open Access Journals (Sweden)

    Takaoka H.

    2003-03-01

    Full Text Available Several Simulium species were investigated as to their biting habits and natural infections with filarial larvae at Ban Pan Fan, Chiang Mai Province, in northern Thailand. Female adults flies landing on or flighting around a human and a water buffalo were collected during the daytime from 06.00 to 19.00 hours on 22 June 2001. As a result, 217 S. nodosum, 86 S. asakoae and two S. nigrogilvum were obtained from a human attractant, and 416 S. nodosum, 25 S. nakhonense, 16 S. asakoae, four 5. fenestratum and two S. nigrogilvum, from a water buffalo. The blood-feeding was confirmed only for S. nodosum and S. nigrogilvum on humans, and for S. nodosum and S. nakhonense on water buffalos. Dissections of these simuliids showed that S. nodosum was naturally infected with developing filarial larvae. Two types of microfilariae were distinguished but only one type of infective larvae. These larvae resembled Onchocerca suzukii, a parasite from a wild Japanese bovid, suggesting that an unknown Onchocerca species from ruminants was transmitted in Thailand. Infection rates with all stages of larvae and third-stage larvae were 2.3 % (14/608 and 1 .0 % (6/608, respectively. This is the first report of natural infections of black flies with Onchocerca larvae in Southeast Asia, and the involved black fly species is shown to be not only anthropophilic but also zoophilic in this region.

  9. 蝇香对人体健康影响的初步研究%Preliminary study on human health effects of flies incense

    Institute of Scientific and Technical Information of China (English)

    杨红艳; 孙菁

    2011-01-01

    目的 初探蝇香对人休健康的潜在影响,分析相关风险因素,为进一步开展蝇香的风险研究提供基础数据和理论依据.方法 调查以问卷为基础,以访谈的方式进行.结果 32.1%的被访者表示蝇香可能对人体有危害,58.2%反映使用蝇香后有不适症状,其中以咳嗽等呼吸道刺激症状为主.69.7%的被访者平均用药时间少于5h/周,29.4%为5~9h/周.每周与蝇香接触的时间在5h以内者,不适症状主要表现为呛鼻、呼吸困难、胸闷、口干舌燥、皮疹以及轻度咳嗽、头昏和头痛;接触时间在5~9h以内者,咳嗽和头昏、头痛加重,另有四肢无力.在接触时间相同的情况下,以残杀威为有效成分的蝇香,产生的不良反应比以氯烯炔菊酯为有效成分的蝇香产生的不良反应明显.结论 不管是以拟除虫菊酯为有效成分还是以氨基甲酸酯为有效成分的蝇香产品对人体都有潜在的危害.%Objective To carry out preliminary study on potential effects of flies incense on human health and analyse relevant risk factors so as to lay foundation for further study on flies incense risks.Methods The survey based on questionaires was conducted by face to face interview respectively.Results 32.1% of participants showed that flies incense might be risky to human health.58.2% of participants had ever suffered from coughing and respiratory stimulation after using flies incense.69.7% of participants used flies incense less than 5 hours/week, 29.4% between 5 and 9 hours/week.Exposing to flies incense less than 5 hours/week, people mainly suffered from respiratory stimulation, like dyspnea, thirsty, rash and mild coughing.Exposing to flies incense between 5 and 9 hours/week, coughing, dizzy and headache aggravated, followed myasthenia of limbs.Under the condition of same exposure, flies incense with effective components of propoxur might be more risky to human health than that of chlorempenthrin.Conclusion No

  10. Species-Specific Adaptations of Trypanosome Morphology and Motility to the Mammalian Host.

    Directory of Open Access Journals (Sweden)

    Joel L Bargul

    2016-02-01

    Full Text Available African trypanosomes thrive in the bloodstream and tissue spaces of a wide range of mammalian hosts. Infections of cattle cause an enormous socio-economic burden in sub-Saharan Africa. A hallmark of the trypanosome lifestyle is the flagellate's incessant motion. This work details the cell motility behavior of the four livestock-parasites Trypanosoma vivax, T. brucei, T. evansi and T. congolense. The trypanosomes feature distinct swimming patterns, speeds and flagellar wave frequencies, although the basic mechanism of flagellar propulsion is conserved, as is shown by extended single flagellar beat analyses. Three-dimensional analyses of the trypanosomes expose a high degree of dynamic pleomorphism, typified by the 'cellular waveform'. This is a product of the flagellar oscillation, the chirality of the flagellum attachment and the stiffness of the trypanosome cell body. The waveforms are characteristic for each trypanosome species and are influenced by changes of the microenvironment, such as differences in viscosity and the presence of confining obstacles. The distinct cellular waveforms may be reflective of the actual anatomical niches the parasites populate within their mammalian host. T. vivax displays waveforms optimally aligned to the topology of the bloodstream, while the two subspecies T. brucei and T. evansi feature distinct cellular waveforms, both additionally adapted to motion in more confined environments such as tissue spaces. T. congolense reveals a small and stiff waveform, which makes these parasites weak swimmers and destined for cell adherence in low flow areas of the circulation. Thus, our experiments show that the differential dissemination and annidation of trypanosomes in their mammalian hosts may depend on the distinct swimming capabilities of the parasites.

  11. Flying Cities

    DEFF Research Database (Denmark)

    Herbelin, Bruno; Lasserre, Sebastien; Ciger, Jan

    2008-01-01

    . This cross-modal interaction not only supports our artistic messages, but also aims at providing anyone with a pleasant and stimulating feedback from her/his speech activity. As the feedback we have received when presenting Flying Cities was very positive, our objective is now to cross the bridge between art......Flying Cities is an artistic installation which generates imaginary cities from the speech of its visitors. Thanks to an original interactive process analyzing people's vocal input to create 3D graphics, a tangible correspondence between speech and visuals opens new possibilities of interaction...

  12. Determinants of Human African Trypanosomiasis Elimination via Paratransgenesis.

    Directory of Open Access Journals (Sweden)

    Jennifer A Gilbert

    2016-03-01

    Full Text Available Human African trypanosomiasis (HAT, transmitted by tsetse flies, has historically infected hundreds of thousands of individuals annually in sub-Saharan Africa. Over the last decade, concerted control efforts have reduced reported cases to below 10,000 annually, bringing complete elimination within reach. A potential technology to eliminate HAT involves rendering the flies resistant to trypanosome infection. This approach can be achieved through the introduction of transgenic Sodalis symbiotic bacteria that have been modified to produce a trypanocide, and propagated via Wolbachia symbionts, which confer a reproductive advantage to the paratransgenic tsetse. However, the population dynamics of these symbionts within tsetse flies have not yet been evaluated. Specifically, the key factors that determine the effectiveness of paratransgenesis have yet to be quantified. To identify the impact of these determinants on T.b. gambiense and T.b. rhodesiense transmission, we developed a mathematical model of trypanosome transmission that incorporates tsetse and symbiont population dynamics. We found that fecundity and mortality penalties associated with Wolbachia or recombinant Sodalis colonization, probabilities of vertical transmission, and tsetse migration rates are fundamental to the feasibility of HAT elimination. For example, we determined that HAT elimination could be sustained over 25 years when Wolbachia colonization minimally impacted fecundity or mortality, and when the probability of recombinant Sodalis vertical transmission exceeded 99.9%. We also found that for a narrow range of recombinant Sodalis vertical transmission probability (99.9-90.6% for T.b. gambiense and 99.9-85.8% for T.b. rhodesiense, cumulative HAT incidence was reduced between 30% and 1% for T.b. gambiense and between 21% and 3% for T.b. rhodesiense, although elimination was not predicted. Our findings indicate that fitness and mortality penalties associated with paratransgenic

  13. Determinants of Human African Trypanosomiasis Elimination via Paratransgenesis.

    Science.gov (United States)

    Gilbert, Jennifer A; Medlock, Jan; Townsend, Jeffrey P; Aksoy, Serap; Ndeffo Mbah, Martial; Galvani, Alison P

    2016-03-01

    Human African trypanosomiasis (HAT), transmitted by tsetse flies, has historically infected hundreds of thousands of individuals annually in sub-Saharan Africa. Over the last decade, concerted control efforts have reduced reported cases to below 10,000 annually, bringing complete elimination within reach. A potential technology to eliminate HAT involves rendering the flies resistant to trypanosome infection. This approach can be achieved through the introduction of transgenic Sodalis symbiotic bacteria that have been modified to produce a trypanocide, and propagated via Wolbachia symbionts, which confer a reproductive advantage to the paratransgenic tsetse. However, the population dynamics of these symbionts within tsetse flies have not yet been evaluated. Specifically, the key factors that determine the effectiveness of paratransgenesis have yet to be quantified. To identify the impact of these determinants on T.b. gambiense and T.b. rhodesiense transmission, we developed a mathematical model of trypanosome transmission that incorporates tsetse and symbiont population dynamics. We found that fecundity and mortality penalties associated with Wolbachia or recombinant Sodalis colonization, probabilities of vertical transmission, and tsetse migration rates are fundamental to the feasibility of HAT elimination. For example, we determined that HAT elimination could be sustained over 25 years when Wolbachia colonization minimally impacted fecundity or mortality, and when the probability of recombinant Sodalis vertical transmission exceeded 99.9%. We also found that for a narrow range of recombinant Sodalis vertical transmission probability (99.9-90.6% for T.b. gambiense and 99.9-85.8% for T.b. rhodesiense), cumulative HAT incidence was reduced between 30% and 1% for T.b. gambiense and between 21% and 3% for T.b. rhodesiense, although elimination was not predicted. Our findings indicate that fitness and mortality penalties associated with paratransgenic symbionts, as well

  14. Serological responses and biomarker evaluation in mice and pigs exposed to tsetse fly bites.

    Directory of Open Access Journals (Sweden)

    Guy Caljon

    2014-05-01

    Full Text Available BACKGROUND: Tsetse flies are obligate blood-feeding insects that transmit African trypanosomes responsible for human sleeping sickness and nagana in livestock. The tsetse salivary proteome contains a highly immunogenic family of the endonuclease-like Tsal proteins. In this study, a recombinant version of Tsal1 (rTsal1 was evaluated in an indirect ELISA to quantify the contact with total Glossina morsitans morsitans saliva, and thus the tsetse fly bite exposure. METHODOLOGY/PRINCIPAL FINDINGS: Mice and pigs were experimentally exposed to different G. m. morsitans exposure regimens, followed by a long-term follow-up of the specific antibody responses against total tsetse fly saliva and rTsal1. In mice, a single tsetse fly bite was sufficient to induce detectable IgG antibody responses with an estimated half-life of 36-40 days. Specific antibody responses could be detected for more than a year after initial exposure, and a single bite was sufficient to boost anti-saliva immunity. Also, plasmas collected from tsetse-exposed pigs displayed increased anti-rTsal1 and anti-saliva IgG levels that correlated with the exposure intensity. A strong correlation between the detection of anti-rTsal1 and anti-saliva responses was recorded. The ELISA test performance and intra-laboratory repeatability was adequate in the two tested animal models. Cross-reactivity of the mouse IgGs induced by exposure to different Glossina species (G. m. morsitans, G. pallidipes, G. palpalis gambiensis and G. fuscipes and other hematophagous insects (Stomoxys calcitrans and Tabanus yao was evaluated. CONCLUSION: This study illustrates the potential use of rTsal1 from G. m. morsitans as a sensitive biomarker of exposure to a broad range of Glossina species. We propose that the detection of anti-rTsal1 IgGs could be a promising serological indicator of tsetse fly presence that will be a valuable tool to monitor the impact of tsetse control efforts on the African continent.

  15. Crystal structures of trypanosomal histidyl-tRNA synthetase illuminate differences between eukaryotic and prokaryotic homologs.

    Science.gov (United States)

    Merritt, Ethan A; Arakaki, Tracy L; Gillespie, J Robert; Larson, Eric T; Kelley, Angela; Mueller, Natascha; Napuli, Alberto J; Kim, Jessica; Zhang, Li; Verlinde, Christophe L M J; Fan, Erkang; Zucker, Frank; Buckner, Frederick S; van Voorhis, Wesley C; Hol, Wim G J

    2010-03-26

    Crystal structures of histidyl-tRNA synthetase (HisRS) from the eukaryotic parasites Trypanosoma brucei and Trypanosoma cruzi provide a first structural view of a eukaryotic form of this enzyme and reveal differences from bacterial homologs. HisRSs in general contain an extra domain inserted between conserved motifs 2 and 3 of the Class II aminoacyl-tRNA synthetase catalytic core. The current structures show that the three-dimensional topology of this domain is very different in bacterial and archaeal/eukaryotic forms of the enzyme. Comparison of apo and histidine-bound trypanosomal structures indicates substantial active-site rearrangement upon histidine binding but relatively little subsequent rearrangement after reaction of histidine with ATP to form the enzyme's first reaction product, histidyladenylate. The specific residues involved in forming the binding pocket for the adenine moiety differ substantially both from the previously characterized binding site in bacterial structures and from the homologous residues in human HisRSs. The essentiality of the single HisRS gene in T. brucei is shown by a severe depression of parasite growth rate that results from even partial suppression of expression by RNA interference.

  16. Microhomology-mediated deletion and gene conversion in African trypanosomes.

    Science.gov (United States)

    Glover, Lucy; Jun, Junho; Horn, David

    2011-03-01

    Antigenic variation in African trypanosomes is induced by DNA double-strand breaks (DSBs). In these protozoan parasites, DSB repair (DSBR) is dominated by homologous recombination (HR) and microhomology-mediated end joining (MMEJ), while non-homologous end joining (NHEJ) has not been reported. To facilitate the analysis of chromosomal end-joining, we established a system whereby inter-allelic repair by HR is lethal due to loss of an essential gene. Analysis of intrachromosomal end joining in individual DSBR survivors exclusively revealed MMEJ-based deletions but no NHEJ. A survey of microhomologies typically revealed sequences of between 5 and 20 bp in length with several mismatches tolerated in longer stretches. Mean deletions were of 54 bp on the side closest to the break and 284 bp in total. Break proximity, microhomology length and GC-content all favored repair and the pattern of MMEJ described above was similar at several different loci across the genome. We also identified interchromosomal gene conversion involving HR and MMEJ at different ends of a duplicated sequence. While MMEJ-based deletions were RAD51-independent, one-sided MMEJ was RAD51 dependent. Thus, we describe the features of MMEJ in Trypanosoma brucei, which is analogous to micro single-strand annealing; and RAD51 dependent, one-sided MMEJ. We discuss the contribution of MMEJ pathways to genome evolution, subtelomere recombination and antigenic variation.

  17. Forensically Important Blow Flies Chrysomya pinguis, C. villeneuvi, and Lucilia porphyrina (Diptera: Calliphoridae) in a Case of Human Remains in Thailand.

    Science.gov (United States)

    Monum, Tawatchai; Sukontason, Kabkaew L; Sribanditmongkol, Pongruk; Sukontason, Kom; Samerjai, Chutharat; Limsopatham, Kwankamol; Suwannayod, Suttida; Klong-Klaew, Tunwadee; Wannasan, Anchalee

    2017-02-01

    This is the first study to report Chrysomya pinguis (Walker) and Lucilia porphyrina (Walker) (Diptera: Calliphoridae) as forensically important blow fly species from human cadavers in Thailand, in addition to Chrysomya villeneuvi (Patton) already known in Thailand. In 2016, a fully decomposed body of an unknown adult male was discovered in a high mountainous forest during winter in Chiang Mai province. The remains were infested heavily with thousands of blow fly larvae feeding simultaneously on them. Morphological identification of adults reared from the larvae, and molecular analysis based on sequencing of 1,247 bp partial mitochondrial cytochrome c oxidase subunit 1 gene (CO1) of the larvae and puparia, confirmed the above mentioned 3 species. The approving forensic fly evidence by molecular approach was described for the first time in Thailand. Moreover, neighbor-joining phylogenetic analysis of the CO1 was performed to compare the relatedness of the species, thereby affirming the accuracy of identification. As species of entomofauna varies among cases in different geographic and climatic circumstances, C. pinguis and L. porphyrina were added to the list of Thai forensic entomology caseworks, including colonizers of human remains in open, high mountainous areas during winter. Further research should focus on these 3 species, for which no developmental data are currently available.

  18. Forensically Important Blow Flies Chrysomya pinguis, C. villeneuvi, and Lucilia porphyrina (Diptera: Calliphoridae) in a Case of Human Remains in Thailand

    Science.gov (United States)

    Monum, Tawatchai; Sukontason, Kabkaew L.; Sribanditmongkol, Pongruk; Sukontason, Kom; Samerjai, Chutharat; Limsopatham, Kwankamol; Suwannayod, Suttida; Klong-klaew, Tunwadee; Wannasan, Anchalee

    2017-01-01

    This is the first study to report Chrysomya pinguis (Walker) and Lucilia porphyrina (Walker) (Diptera: Calliphoridae) as forensically important blow fly species from human cadavers in Thailand, in addition to Chrysomya villeneuvi (Patton) already known in Thailand. In 2016, a fully decomposed body of an unknown adult male was discovered in a high mountainous forest during winter in Chiang Mai province. The remains were infested heavily with thousands of blow fly larvae feeding simultaneously on them. Morphological identification of adults reared from the larvae, and molecular analysis based on sequencing of 1,247 bp partial mitochondrial cytochrome c oxidase subunit 1 gene (CO1) of the larvae and puparia, confirmed the above mentioned 3 species. The approving forensic fly evidence by molecular approach was described for the first time in Thailand. Moreover, neighbor-joining phylogenetic analysis of the CO1 was performed to compare the relatedness of the species, thereby affirming the accuracy of identification. As species of entomofauna varies among cases in different geographic and climatic circumstances, C. pinguis and L. porphyrina were added to the list of Thai forensic entomology caseworks, including colonizers of human remains in open, high mountainous areas during winter. Further research should focus on these 3 species, for which no developmental data are currently available. PMID:28285509

  19. Parasite development and host responses during the establishment of Trypanosoma brucei infection transmitted by tsetse fly.

    Science.gov (United States)

    Barry, J D; Emergy, D L

    1984-02-01

    Following inoculation of Trypanosoma brucei into large mammals by the tsetse fly a local skin reaction, the 'chancre', develops due to trypanosome proliferation. We have cannulated the afferent and efferent lymphatics of the draining lymph node in goats and examined the onset of a cellular reaction, the emigration of the parasite from the chancre and the development of both antigenic variation and the specific immune response. The chancre first became detectable by day 3 post-infection, peaked by day 6 and then subsided. Lymphocyte output increased 6- to 8-fold by day 10 and the number of lymphoblasts increased 50-fold in this period. Both then declined. Trypanosomes were detected in lymph 1-2 days before the chancre, peaked by days 5-6, declined during development of the chancre and then peaked again. The bloodstream population appeared by days 4-5 and displayed different kinetics from that in lymph. Recirculation of parasites through the lymphatics ensued. Lymph-borne trypanosome populations were highly pleomorphic. Parasites in lymph expressed firstly a mixture of the Variable Antigen Types (VATs) which are found characteristically in the tsetse fly, this being followed by a mixture of other VATs. The two groups overlapped in appearance. In the bloodstream the same sequence of events occurred although 2 or 3 days later. The specific antibody response, as measured by radioimmunoassay and agglutination, arose within a few days of the first detection of each VAT. Activities appeared first in the lymph and then in plasma.

  20. Presence of trypanosome species and anemic status of dogs in Zuru, Nigeria

    Directory of Open Access Journals (Sweden)

    Rafi Rabecca Tono

    2015-10-01

    Full Text Available The aim of this research is to study the presence and prevalence of trypanosome species in local dogs between January and July, 2010 in the Zuru area of Kebbi State, Nigeria.Standard trypanosome detection methods comprising of wet blood films, thin films and microhaematocrit centrifugation technique were used to detect trypanosomes; while the degree of anemia was determined through the use of FAMACHA® eye colour chart and packed cell volume values. A total of 567 dogs were enumerated in fourteen locations within the study area out of which 192 (33.7% were randomly examined and 4 (2.08% were positive for the presence of trypanosomes. All positive samples morphologically belong to the Trypanosoma brucei group. The obtained PCV values showed that 50 (26.04% dogs were anemic, while the FAMACHA® detected anemia status of varying degrees in 104 (77% sampled dogs.These findings are significant as this is the first time that the trypanosome infection will be reported in dogs from the study area. This study establishes the presence of Trypanosoma brucei group in the study area, which is of zoonotic and economic importance.

  1. Two new Trypanosoma species from African birds, with notes on the taxonomy of avian trypanosomes.

    Science.gov (United States)

    Valkiūnas, Gediminas; Iezhova, Tatjana A; Carlson, Jenny S; Sehgal, Ravinder N M

    2011-10-01

    Trypanosoma anguiformis n. sp. and Trypanosoma polygranularis n. sp. are described from the African olive sunbird, Cyanomitra olivacea, and Latham's forest francolin, Francolinus lathami, respectively, based on the morphology of their hematozoic trypomastigotes and partial sequences of the small subunit ribosomal RNA gene. Both new species belong to the group of small non-striated avian trypanosomes (Trypanosoma anguiformis can be readily distinguished from other small avian trypanosomes due to its markedly attenuated (snake-shaped) form of the hematozoic trypomastigotes and the dumbbell-shaped nucleus of the parasite. Trypanosoma polygranularis is readily distinguishable due to the markedly off-center (anteriorly) located nucleus, numerous azurophilic granules that are arranged in a line following the undulating membrane, and the large kinetoplast (with an area up to 1.7 µm(2) [1.1 µm(2) on average]). Illustrations of hematozoic trypomastigotes of the new species are given, and DNA lineages associated with these parasites are reported. The current situation in species taxonomy of avian trypanosomes is discussed. We call for the redescription of valid species of avian trypanosomes from their type vertebrate hosts and type localities by using morphological and polymerase chain reaction-based techniques as an initial essential step towards revising the species composition of avian trypanosomes and reconstructing the taxonomy of these organisms.

  2. THE CRYSTAL-STRUCTURE OF THE OPEN AND THE CLOSED CONFORMATION OF THE FLEXIBLE LOOP OF TRYPANOSOMAL TRIOSEPHOSPHATE ISOMERASE

    NARCIS (Netherlands)

    WIERENGA, RK; NOBLE, MEM; POSTMA, JPM; GROENDIJK, H; KALK, KH; HOL, WGJ; OPPERDOES, FR

    1991-01-01

    Triosephosphate isomerase has an important loop near the active site which can exist in a "closed" and in an "open" conformation. Here we describe the structural properties of this "flexible" loop observed in two different structures of trypanosomal triosephosphate isomerase. Trypanosomal

  3. First Human Cases of Leishmania (Viannia) lainsoni Infection and a Search for the Vector Sand Flies in Ecuador.

    Science.gov (United States)

    Kato, Hirotomo; Bone, Abdon E; Mimori, Tatsuyuki; Hashiguchi, Kazue; Shiguango, Gonzalo F; Gonzales, Silvio V; Velez, Lenin N; Guevara, Angel G; Gomez, Eduardo A; Hashiguchi, Yoshihisa

    2016-05-01

    An epidemiological study of leishmaniasis was performed in Amazonian areas of Ecuador since little information on the prevalent Leishmania and sand fly species responsible for the transmission is available. Of 33 clinical specimens from patients with cutaneous leishmaniasis (CL), causative parasites were identified in 25 samples based on cytochrome b gene analysis. As reported previously, Leishmania (Viannia) guyanensis and L. (V.) braziliensis were among the causative agents identified. In addition, L. (V.) lainsoni, for which infection is reported in Brazil, Bolivia, Peru, Suriname, and French Guiana, was identified in patients with CL from geographically separate areas in the Ecuadorian Amazon, corroborating the notion that L. (V.) lainsoni is widely distributed in South America. Sand flies were surveyed around the area where a patient with L. (V.) lainsoni was suspected to have been infected. However, natural infection of sand flies by L. (V.) lainsoni was not detected. Further extensive vector searches are necessary to define the transmission cycle of L. (V.) lainsoni in Ecuador.

  4. Detection and characterization of Wolbachia infections in laboratory and natural populations of different species of tsetse flies (genus Glossina

    Directory of Open Access Journals (Sweden)

    Doudoumis Vangelis

    2012-01-01

    Full Text Available Abstract Background Wolbachia is a genus of endosymbiotic α-Proteobacteria infecting a wide range of arthropods and filarial nematodes. Wolbachia is able to induce reproductive abnormalities such as cytoplasmic incompatibility (CI, thelytokous parthenogenesis, feminization and male killing, thus affecting biology, ecology and evolution of its hosts. The bacterial group has prompted research regarding its potential for the control of agricultural and medical disease vectors, including Glossina spp., which transmits African trypanosomes, the causative agents of sleeping sickness in humans and nagana in animals. Results In the present study, we employed a Wolbachia specific 16S rRNA PCR assay to investigate the presence of Wolbachia in six different laboratory stocks as well as in natural populations of nine different Glossina species originating from 10 African countries. Wolbachia was prevalent in Glossina morsitans morsitans, G. morsitans centralis and G. austeni populations. It was also detected in G. brevipalpis, and, for the first time, in G. pallidipes and G. palpalis gambiensis. On the other hand, Wolbachia was not found in G. p. palpalis, G. fuscipes fuscipes and G. tachinoides. Wolbachia infections of different laboratory and natural populations of Glossina species were characterized using 16S rRNA, the wsp (Wolbachia Surface Protein gene and MLST (Multi Locus Sequence Typing gene markers. This analysis led to the detection of horizontal gene transfer events, in which Wobachia genes were inserted into the tsetse flies fly nuclear genome. Conclusions Wolbachia infections were detected in both laboratory and natural populations of several different Glossina species. The characterization of these Wolbachia strains promises to lead to a deeper insight in tsetse flies-Wolbachia interactions, which is essential for the development and use of Wolbachia-based biological control methods.

  5. The detection and treatment of human African trypanosomiasis

    Directory of Open Access Journals (Sweden)

    Bouteille B

    2012-06-01

    Full Text Available Bernard Bouteille,1 Alain Buguet21Laboratory of Parasitology, Dupuytren University Hospital of Limoges, France; 2Polyclinic Marie-Louise Poto-Djembo, Pointe-Noire, CongoAbstract: Human African trypanosomiasis (HAT is caused by the injection of Trypanosoma brucei (T. b. gambiense or T. b. rhodesiense by Glossina, the tsetse fly. Three historical eras followed the exclusive clinical approach of the 19th century. At the turn of the century, the “initial research” era was initiated because of the dramatic spread of HAT throughout intertropical Africa, and scientists discovered the agent and its vector. Two entities, recurrent fever and sleeping sickness, were then considered a continuum between hemolymphatic stage 1 and meningoencephalitic stage 2. Treatments were developed. Soon after World War I, specific services and mobile teams were created, initiating the “epidemiological” era, during which populations were visited, screened, and treated. As a result, by 1960, annual new cases were rare. New mass screening and staging tools were then developed in a third, “modern” era, especially to counter a new epidemic wave. Currently, diagnosis still relies on microscopic detection of trypanosomes without (wet and thick blood films or with concentration techniques (capillary tube centrifugation, miniature anion-exchange centrifugation technique. Staging is a vital step.Stage 1 patients are treated on site with pentamidine or suramin. However, stage 2 patients are treated in specialized facilities, using drugs that are highly toxic and/or that require complex administration procedures (melarsoprol, eflornithine, or nifurtimox-eflornithine combination therapy. Suramin and melarsoprol are the only medications active against Rhodesian HAT. Staging still relies on cerebrospinal fluid examination for trypanosome detection and white blood cell counts: stage 1, absence of trypanosomes, white blood cell counts ≤ 5/µL; stage 2, presence of

  6. Anti-trypanosomal activity of non-peptidic nitrile-based cysteine protease inhibitors.

    Science.gov (United States)

    Burtoloso, Antonio C B; de Albuquerque, Sérgio; Furber, Mark; Gomes, Juliana C; Gonçalez, Cristiana; Kenny, Peter W; Leitão, Andrei; Montanari, Carlos A; Quilles, José Carlos; Ribeiro, Jean F R; Rocha, Josmar R

    2017-02-01

    The cysteine protease cruzipain is considered to be a validated target for therapeutic intervention in the treatment of Chagas disease. Anti-trypanosomal activity against the CL Brener strain of T. cruzi was observed in the 0.1 μM to 1 μM range for three nitrile-based cysteine protease inhibitors based on two scaffolds known to be associated with cathepsin K inhibition. The two compounds showing the greatest potency against the trypanosome were characterized by EC50 values (0.12 μM and 0.25 μM) that were an order of magnitude lower than the corresponding Ki values measured against cruzain, a recombinant form of cruzipain, in an enzyme inhibition assay. This implies that the anti-trypanosomal activity of these two compounds may not be explained only by the inhibition of the cruzain enzyme, thereby triggering a putative polypharmacological profile towards cysteine proteases.

  7. Flying Cities

    DEFF Research Database (Denmark)

    Ciger, Jan

    2006-01-01

    The Flying Cities artistic installation brings to life imaginary cities made from the speech input of visitors. In this article we describe the original interactive process generating real time 3D graphics from spectators' vocal inputs. This example of cross-modal interaction has the nice property...... of providing a tangible correspondence between the two spaces. This interaction mean has proved to suit the artistic expression well but it also aims at providing anyone with a pleasant and stimulating feedback from speech activity, a new medium for creativity and a way to visually perceive a vocal performance....... As the feedback we have received when presenting Flying Cities was very positive, our objective now is to cross the bridge between art and the potential applications to the rehabilitation of people with reduced mobility or for the treatment of language impairments....

  8. Tsetse fly (G. f. fuscipes) distribution in the Lake Victoria basin of Uganda.

    Science.gov (United States)

    Albert, Mugenyi; Wardrop, Nicola A; Atkinson, Peter M; Torr, Steve J; Welburn, Susan C

    2015-04-01

    Tsetse flies transmit trypanosomes, the causative agent of human and animal African trypanosomiasis. The tsetse vector is extensively distributed across sub-Saharan Africa. Trypanosomiasis maintenance is determined by the interrelationship of three elements: vertebrate host, parasite and the vector responsible for transmission. Mapping the distribution and abundance of tsetse flies assists in predicting trypanosomiasis distributions and developing rational strategies for disease and vector control. Given scarce resources to carry out regular full scale field tsetse surveys to up-date existing tsetse maps, there is a need to devise inexpensive means for regularly obtaining dependable area-wide tsetse data to guide control activities. In this study we used spatial epidemiological modelling techniques (logistic regression) involving 5000 field-based tsetse-data (G. f. fuscipes) points over an area of 40,000 km2, with satellite-derived environmental surrogates composed of precipitation, temperature, land cover, normalised difference vegetation index (NDVI) and elevation at the sub-national level. We used these extensive tsetse data to analyse the relationships between presence of tsetse (G. f. fuscipes) and environmental variables. The strength of the results was enhanced through the application of a spatial autologistic regression model (SARM). Using the SARM we showed that the probability of tsetse presence increased with proportion of forest cover and riverine vegetation. The key outputs are a predictive tsetse distribution map for the Lake Victoria basin of Uganda and an improved understanding of the association between tsetse presence and environmental variables. The predicted spatial distribution of tsetse in the Lake Victoria basin of Uganda will provide significant new information to assist with the spatial targeting of tsetse and trypanosomiasis control.

  9. Tsetse fly (G. f. fuscipes distribution in the Lake Victoria basin of Uganda.

    Directory of Open Access Journals (Sweden)

    Mugenyi Albert

    2015-04-01

    Full Text Available Tsetse flies transmit trypanosomes, the causative agent of human and animal African trypanosomiasis. The tsetse vector is extensively distributed across sub-Saharan Africa. Trypanosomiasis maintenance is determined by the interrelationship of three elements: vertebrate host, parasite and the vector responsible for transmission. Mapping the distribution and abundance of tsetse flies assists in predicting trypanosomiasis distributions and developing rational strategies for disease and vector control. Given scarce resources to carry out regular full scale field tsetse surveys to up-date existing tsetse maps, there is a need to devise inexpensive means for regularly obtaining dependable area-wide tsetse data to guide control activities. In this study we used spatial epidemiological modelling techniques (logistic regression involving 5000 field-based tsetse-data (G. f. fuscipes points over an area of 40,000 km2, with satellite-derived environmental surrogates composed of precipitation, temperature, land cover, normalised difference vegetation index (NDVI and elevation at the sub-national level. We used these extensive tsetse data to analyse the relationships between presence of tsetse (G. f. fuscipes and environmental variables. The strength of the results was enhanced through the application of a spatial autologistic regression model (SARM. Using the SARM we showed that the probability of tsetse presence increased with proportion of forest cover and riverine vegetation. The key outputs are a predictive tsetse distribution map for the Lake Victoria basin of Uganda and an improved understanding of the association between tsetse presence and environmental variables. The predicted spatial distribution of tsetse in the Lake Victoria basin of Uganda will provide significant new information to assist with the spatial targeting of tsetse and trypanosomiasis control.

  10. A set of amino acids found to occur more frequently in human and fly than in plant and yeast proteomes consists of non-essential amino acids

    OpenAIRE

    2007-01-01

    We investigated the hypothesis that essential amino acids are being replaced in proteins by non-essential amino acids.We compared the amino acid composition in human, worm and fly proteomes, organisms that cannot synthesize all amino acids, with the amino acids of the proteomes of plant, bakers yeast and budding yeast, which are capable of synthesizing them. The analysis covered 460,737 proteins (212,197,907 amino acids). The data suggest a bias towards the usage of non-essential ami...

  11. Wolbachia symbiont infections induce strong cytoplasmic incompatibility in the tsetse fly Glossina morsitans.

    Directory of Open Access Journals (Sweden)

    Uzma Alam

    2011-12-01

    Full Text Available Tsetse flies are vectors of the protozoan parasite African trypanosomes, which cause sleeping sickness disease in humans and nagana in livestock. Although there are no effective vaccines and efficacious drugs against this parasite, vector reduction methods have been successful in curbing the disease, especially for nagana. Potential vector control methods that do not involve use of chemicals is a genetic modification approach where flies engineered to be parasite resistant are allowed to replace their susceptible natural counterparts, and Sterile Insect technique (SIT where males sterilized by chemical means are released to suppress female fecundity. The success of genetic modification approaches requires identification of strong drive systems to spread the desirable traits and the efficacy of SIT can be enhanced by identification of natural mating incompatibility. One such drive mechanism results from the cytoplasmic incompatibility (CI phenomenon induced by the symbiont Wolbachia. CI can also be used to induce natural mating incompatibility between release males and natural populations. Although Wolbachia infections have been reported in tsetse, it has been a challenge to understand their functional biology as attempts to cure tsetse of Wolbachia infections by antibiotic treatment damages the obligate mutualistic symbiont (Wigglesworthia, without which the flies are sterile. Here, we developed aposymbiotic (symbiont-free and fertile tsetse lines by dietary provisioning of tetracycline supplemented blood meals with yeast extract, which rescues Wigglesworthia-induced sterility. Our results reveal that Wolbachia infections confer strong CI during embryogenesis in Wolbachia-free (Gmm(Apo females when mated with Wolbachia-infected (Gmm(Wt males. These results are the first demonstration of the biological significance of Wolbachia infections in tsetse. Furthermore, when incorporated into a mathematical model, our results confirm that Wolbachia can

  12. Flying Cities

    DEFF Research Database (Denmark)

    Ciger, Jan

    2006-01-01

    of providing a tangible correspondence between the two spaces. This interaction mean has proved to suit the artistic expression well but it also aims at providing anyone with a pleasant and stimulating feedback from speech activity, a new medium for creativity and a way to visually perceive a vocal performance......The Flying Cities artistic installation brings to life imaginary cities made from the speech input of visitors. In this article we describe the original interactive process generating real time 3D graphics from spectators' vocal inputs. This example of cross-modal interaction has the nice property...

  13. Flying Fortress

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    当欧洲的年轻人想到关于德国的两种熊,一个是传统的布娃娃熊,另一个就是充满欧洲街头墙上的Teddy熊涂鸦,而这个涂鸦熊的创作者就是著名的涂鸦艺术家“Flying Fortress”,他称这些熊军队为“Teddy Tmops”。

  14. Risk Zones of Human Leishmaniases in the Western Mediterranean Basin: Correlations between Vector Sand Flies, Bioclimatology and Phytosociology

    OpenAIRE

    Rispail Philippe; Dereure Jacques; Jarry Daniel

    2002-01-01

    Correspondence analysis was applied to sand fly sampling in 865 stations from the Western Mediterranean basin. The position of each of 24 species was determined with respect to the bioclimatic belts. Thus, the multidimensional analyses manifest clear correlations between bioclimatic belts and their expression in the area, the phytosociological groupings, and vector species of visceral and cutaneous leishmaniases. The transfer of these data to usual maps allows to delimit the geographical dist...

  15. First Human Cases of Leishmania (Viannia lainsoni Infection and a Search for the Vector Sand Flies in Ecuador.

    Directory of Open Access Journals (Sweden)

    Hirotomo Kato

    2016-05-01

    Full Text Available An epidemiological study of leishmaniasis was performed in Amazonian areas of Ecuador since little information on the prevalent Leishmania and sand fly species responsible for the transmission is available. Of 33 clinical specimens from patients with cutaneous leishmaniasis (CL, causative parasites were identified in 25 samples based on cytochrome b gene analysis. As reported previously, Leishmania (Viannia guyanensis and L. (V. braziliensis were among the causative agents identified. In addition, L. (V. lainsoni, for which infection is reported in Brazil, Bolivia, Peru, Suriname, and French Guiana, was identified in patients with CL from geographically separate areas in the Ecuadorian Amazon, corroborating the notion that L. (V. lainsoni is widely distributed in South America. Sand flies were surveyed around the area where a patient with L. (V. lainsoni was suspected to have been infected. However, natural infection of sand flies by L. (V. lainsoni was not detected. Further extensive vector searches are necessary to define the transmission cycle of L. (V. lainsoni in Ecuador.

  16. First Human Cases of Leishmania (Viannia) lainsoni Infection and a Search for the Vector Sand Flies in Ecuador

    Science.gov (United States)

    Kato, Hirotomo; Bone, Abdon E.; Mimori, Tatsuyuki; Hashiguchi, Kazue; Shiguango, Gonzalo F.; Gonzales, Silvio V.; Velez, Lenin N.; Guevara, Angel G.; Gomez, Eduardo A.; Hashiguchi, Yoshihisa

    2016-01-01

    An epidemiological study of leishmaniasis was performed in Amazonian areas of Ecuador since little information on the prevalent Leishmania and sand fly species responsible for the transmission is available. Of 33 clinical specimens from patients with cutaneous leishmaniasis (CL), causative parasites were identified in 25 samples based on cytochrome b gene analysis. As reported previously, Leishmania (Viannia) guyanensis and L. (V.) braziliensis were among the causative agents identified. In addition, L. (V.) lainsoni, for which infection is reported in Brazil, Bolivia, Peru, Suriname, and French Guiana, was identified in patients with CL from geographically separate areas in the Ecuadorian Amazon, corroborating the notion that L. (V.) lainsoni is widely distributed in South America. Sand flies were surveyed around the area where a patient with L. (V.) lainsoni was suspected to have been infected. However, natural infection of sand flies by L. (V.) lainsoni was not detected. Further extensive vector searches are necessary to define the transmission cycle of L. (V.) lainsoni in Ecuador. PMID:27191391

  17. The Trypanosome Exocyst: A Conserved Structure Revealing a New Role in Endocytosis

    Science.gov (United States)

    Boehm, Cordula M.; Obado, Samson; Gadelha, Catarina; Kaupisch, Alexandra; Manna, Paul T.; Gould, Gwyn W.; Rout, Michael P.; Field, Mark C.

    2017-01-01

    Membrane transport is an essential component of pathogenesis for most infectious organisms. In African trypanosomes, transport to and from the plasma membrane is closely coupled to immune evasion and antigenic variation. In mammals and fungi an octameric exocyst complex mediates late steps in exocytosis, but comparative genomics suggested that trypanosomes retain only six canonical subunits, implying mechanistic divergence. We directly determined the composition of the Trypanosoma brucei exocyst by affinity isolation and demonstrate that the parasite complex is nonameric, retaining all eight canonical subunits (albeit highly divergent at the sequence level) plus a novel essential subunit, Exo99. Exo99 and Sec15 knockdowns have remarkably similar phenotypes in terms of viability and impact on morphology and trafficking pathways. Significantly, both Sec15 and Exo99 have a clear function in endocytosis, and global proteomic analysis indicates an important role in maintaining the surface proteome. Taken together these data indicate additional exocyst functions in trypanosomes, which likely include endocytosis, recycling and control of surface composition. Knockdowns in HeLa cells suggest that the role in endocytosis is shared with metazoan cells. We conclude that, whilst the trypanosome exocyst has novel components, overall functionality appears conserved, and suggest that the unique subunit may provide therapeutic opportunities. PMID:28114397

  18. Isolation and phylogenetic relationships of bat trypanosomes from different biomes in Mato Grosso, Brazil.

    Science.gov (United States)

    Marcili, Arlei; da Costa, Andrea P; Soares, Herbert S; Acosta, Igor da C L; de Lima, Julia T R; Minervino, Antonio H H; Melo, Andréia T L; Aguiar, Daniel M; Pacheco, Richard C; Gennari, Solange M

    2013-12-01

    In the order Chiroptera, more than 30 trypanosome species belonging to the subgenera Herpetosoma, Schizotrypanum, Megatrypanum, and Trypanozoon have been described. The species Trypanosoma cruzi , Trypanosoma cruzi marinkellei, and Trypanosoma dionisii are the most common in bats and belong to the Schizotrypanum subgenus. Bats from 2 different biomes, Pantanal and Amazonia/Cerrado in the state of Mato Grosso, Brazil, were evaluated according to the presence of trypanosome parasites by means of hemoculture and PCR in primary samples (blood samples). A total of 211 bats from 20 different species were caught and the trypanosome prevalence, evaluated through hemoculture, was 9.0% (19), 15.5% (13), and 4.8% (6) in the municipalities of Confresa (Amazonia/Cerrado biome) and Poconé (Pantanal biome). Among the 123 primary samples obtained from the bats, only 3 (2.4%) were positive. Phylogenetic analysis using trypanosomatid barcoding (V7V8 region of SSU rDNA) identified all the isolates and primary samples as T. c. marinkellei. The sequences of the isolates were segregated according to the bat host genus or species and suggest that co-evolutionary patterns exist between hosts and parasites. Further studies in different Brazilian regions and biomes need to be conducted in order to gain real understanding of the diversity of trypanosomes in bats.

  19. Polycistronic trypanosome mRNAs are a target for the exosome

    Science.gov (United States)

    Kramer, Susanne; Piper, Sophie; Estevez, Antonio; Carrington, Mark

    2016-01-01

    Eukaryotic cells have several mRNA quality control checkpoints to avoid the production of aberrant proteins. Intron-containing mRNAs are actively degraded by the nuclear exosome, prevented from nuclear exit and, if these systems fail, degraded by the cytoplasmic NMD machinery. Trypanosomes have only two introns. However, they process mRNAs from long polycistronic precursors by trans-splicing and polycistronic mRNA molecules frequently arise from any missed splice site. Here, we show that RNAi depletion of the trypanosome exosome, but not of the cytoplasmic 5′-3′ exoribonuclease XRNA or the NMD helicase UPF1, causes accumulation of oligocistronic mRNAs. We have also revisited the localization of the trypanosome exosome by expressing eYFP-fusion proteins of the exosome subunits RRP44 and RRP6. Both proteins are significantly enriched in the nucleus. Together with published data, our data suggest a major nuclear function of the trypanosome exosome in rRNA, snoRNA and mRNA quality control. PMID:26946399

  20. Trypanosoma culicavium sp. nov., an avian trypanosome transmitted by Culex mosquitoes.

    Science.gov (United States)

    Votýpka, Jan; Szabová, Jana; Rádrová, Jana; Zídková, Lenka; Svobodová, Milena

    2012-03-01

    A novel avian trypanosome, Trypanosoma culicavium sp. nov., isolated from Culex mosquitoes, is described on the basis of naturally and experimentally infected vectors and bird hosts, localization in the vector, morphological characters and molecular data. This study provides the first comprehensive description of a trypanosome species transmitted by mosquitoes, in which parasites form plugs and rosettes on the stomodeal valve. Trypanosomes occurred as long epimastigotes and short trypomastigotes in vectors and culture and as long trypomastigotes in birds. Transmission of parasites to bird hosts was achieved exclusively by ingestion of experimentally infected Culex mosquito females by canaries (Serinus canaria), but not by Japanese quails (Coturnix japonica), nor by the bite of infected vectors, nor by ingestion of parasites from laboratory cultures. Transmission experiments and the identity of isolates from collared flycatchers (Ficedula albicollis) and Culex mosquitoes suggests that the natural hosts of T. culicavium are insectivorous songbirds (Passeriformes). Phylogenetic analyses of small-subunit rRNA and glycosomal glyceraldehyde-3-phosphate dehydrogenase gene sequences demonstrated that T. culicavium sp. nov. is more related to Trypanosoma corvi than to other avian trypanosomes (e.g. Trypanosoma avium and Trypanosoma bennetti).

  1. Trypanosome Motion Represents an Adaptation to the Crowded Environment of the Vertebrate Bloodstream

    Science.gov (United States)

    Heddergott, Niko; Krüger, Timothy; Babu, Sujin B.; Wei, Ai; Stellamanns, Erik; Uppaluri, Sravanti; Pfohl, Thomas; Stark, Holger; Engstler, Markus

    2012-01-01

    Blood is a remarkable habitat: it is highly viscous, contains a dense packaging of cells and perpetually flows at velocities varying over three orders of magnitude. Only few pathogens endure the harsh physical conditions within the vertebrate bloodstream and prosper despite being constantly attacked by host antibodies. African trypanosomes are strictly extracellular blood parasites, which evade the immune response through a system of antigenic variation and incessant motility. How the flagellates actually swim in blood remains to be elucidated. Here, we show that the mode and dynamics of trypanosome locomotion are a trait of life within a crowded environment. Using high-speed fluorescence microscopy and ordered micro-pillar arrays we show that the parasites mode of motility is adapted to the density of cells in blood. Trypanosomes are pulled forward by the planar beat of the single flagellum. Hydrodynamic flow across the asymmetrically shaped cell body translates into its rotational movement. Importantly, the presence of particles with the shape, size and spacing of blood cells is required and sufficient for trypanosomes to reach maximum forward velocity. If the density of obstacles, however, is further increased to resemble collagen networks or tissue spaces, the parasites reverse their flagellar beat and consequently swim backwards, in this way avoiding getting trapped. In the absence of obstacles, this flagellar beat reversal occurs randomly resulting in irregular waveforms and apparent cell tumbling. Thus, the swimming behavior of trypanosomes is a surprising example of micro-adaptation to life at low Reynolds numbers. For a precise physical interpretation, we compare our high-resolution microscopic data to results from a simulation technique that combines the method of multi-particle collision dynamics with a triangulated surface model. The simulation produces a rotating cell body and a helical swimming path, providing a functioning simulation method for a

  2. An update of the tsetse fly (Diptera: Glossinidae distribution and African animal trypanosomosis prevalence in north-eastern KwaZulu-Natal, South Africa

    Directory of Open Access Journals (Sweden)

    Chantel J. de Beer

    2016-03-01

    Full Text Available An unpredicted outbreak of African animal trypanosomosis or nagana in 1990 in north-eastern KwaZulu-Natal necessitated an emergency control programme, utilising the extensive cattledipping system in the area, as well as a reassessment of the tsetse and trypanosomosis problem in the province. Since 1990, sporadic blood sampling of cattle at the dip tanks in the naganainfested areas were undertaken to identify trypanosome species involved and to determine the infection prevalence in cattle. The distribution and species composition of the tsetse populations in the area were also investigated. From November 2005 to November 2007 selected dip tanks were surveyed for trypanosome infection prevalence. During April 2005 to August 2009 the distribution and abundance of tsetse populations were assessed with odour-baited H traps. The tsetse and trypanosome distribution maps were updated and potential correlations between tsetse apparent densities (ADs and the prevalence of trypanosomosis were assessed. Glossina brevipalpis Newstead and Glossina austeni Newstead were recorded in locations where they have not previously been collected. No significant correlation between tsetse relative abundance and nagana prevalence was found, which indicated complex interactions between tsetse fly presence and disease prevalence. This was epitomised by data that indicated that despite large differences in the ADs of G. austeni and G. brevipalpis, trypanosome infection prevalence was similar in all three districts in the area. This study clearly indicated that both tsetse species play significant roles in trypanosome transmission and that it will be essential that any control strategy, which aims at sustainable management of the disease, should target both species.Keywords: Tsetse distribution; Glossina brevipalpis; Glossina austeni; trypanosome infection prevalence

  3. Risk zones of human Leishmaniases in the Western Mediterranean basin: correlations between vector sand flies, bioclimatology and phytosociology.

    Science.gov (United States)

    Rispail, Philippe; Dereure, Jacques; Jarry, Daniel

    2002-06-01

    Correspondence analysis was applied to sand fly sampling in 865 stations from the Western Mediterranean basin. The position of each of 24 species was determined with respect to the bioclimatic belts. Thus, the multidimensional analyses manifest clear correlations between bioclimatic belts and their expression in the area, the phytosociological groupings, and vector species of visceral and cutaneous leishmaniases. The transfer of these data to usual maps allows to delimit the geographical distribution of these diseases in the Western Mediterranean basin and contributes to the determination, in a rational manner, of the high risk zones.

  4. Human onchocerciasis in the Amazonian area of southern Venezuela: spatial and temporal variations in biting and parity rates of black fly (Diptera: Simuliidae) vectors.

    Science.gov (United States)

    Grillet, M E; Basáñez, M G; Vivas-Martínez, S; Villamizar, N; Frontado, H; Cortez, J; Coronel, P; Botto, C

    2001-07-01

    We investigated some entomological factors underlying altitudinal prevalence variation in the Venezuelan Amazonia human onchocerciasis focus. Spatial and temporal variation in relative abundance, daily biting rate, proportion of parous flies, and monthly parous biting rate were studied for the three main simuliid vectors (based on their vectorial competence: Simulium oyapockense s.l. Floch & Abonnenc approximately = S. incrustatum Lutz variables included monthly rainfall and maximum river height. Simuliid species composition itself varied along the altitudinal and prevalence gradient. S. oyapockense s.l. prevailed below 150 m. Above this altitude and up to 240 m, S. incrustatum and S. guianense s.l. became more frequently and evenly collected along A but not along B, where S. incrustatum remained absent. The daily biting rate of S. oyapockense s.l. was higher during the dry season along A, whereas the converse took place along B. Daily biting rate of S. incrustatum was lowest during early rains. By contrast, the daily biting rate of S. guianense s.l. was highest during this period. There was a significant negative cross-correlation between proportion of parous of S. oyapockense s.l. and river height (2 and 3 mo lagged), whereas this variable (1 and 2 mo lagged) was positively correlated with the proportion of parous flies for S. incrustatum. Monthly parous biting rate values suggest that the months contributing most to onchocerciasis transmission in the area are likely to be the dry season and the transition periods between seasons.

  5. Evolutionary insights from bat trypanosomes: morphological, developmental and phylogenetic evidence of a new species, Trypanosoma (Schizotrypanum) erneyi sp. nov., in African bats closely related to Trypanosoma (Schizotrypanum) cruzi and allied species.

    Science.gov (United States)

    Lima, Luciana; Silva, Flávia Maia da; Neves, Luis; Attias, Márcia; Takata, Carmen S A; Campaner, Marta; de Souza, Wanderley; Hamilton, Patrick B; Teixeira, Marta M G

    2012-11-01

    Parasites of the genus Trypanosoma are common in bats and those of the subgenus Schizotrypanum are restricted to bats throughout the world, with the exception of Trypanosoma (Schizotrypanum) cruzi that also infects other mammals and is restricted to the American Continent. We have characterized trypanosome isolates from Molossidae bats captured in Mozambique, Africa. Morphology and behaviour in culture, supported by phylogenetic inferences using SSU (small subunit) rRNA, gGAPDH (glycosomal glyceraldehyde 3-phosphate dehydrogenase) and Cyt b (cytochrome b) genes, allowed to classify the isolates as a new Schizotrypanum species named Trypanosoma (Schizotrypanum) erneyi sp. nov. This is the first report of a Schizotrypanum species from African bats cultured, characterized morphologically and biologically, and positioned in phylogenetic trees. The unprecedented finding of a new species of the subgenus Schizotrypanum from Africa that is closest related to the America-restricted Trypanosoma (Schizotrypanum) cruzi marinkellei and T. cruzi provides new insights into the origin and evolutionary history of T. cruzi and closely related bat trypanosomes. Altogether, data from our study support the hypothesis of an ancestor trypanosome parasite of bats evolving to infect other mammals, even humans, and adapted to transmission by triatomine bugs in the evolutionary history of T. cruzi in the New World.

  6. Multiple independent insertions of 5S rRNA genes in the spliced-leader gene family of trypanosome species.

    Science.gov (United States)

    Beauparlant, Marc A; Drouin, Guy

    2014-02-01

    Analyses of the 5S rRNA genes found in the spliced-leader (SL) gene repeat units of numerous trypanosome species suggest that such linkages were not inherited from a common ancestor, but were the result of independent 5S rRNA gene insertions. In trypanosomes, 5S rRNA genes are found either in the tandemly repeated units coding for SL genes or in independent tandemly repeated units. Given that trypanosome species where 5S rRNA genes are within the tandemly repeated units coding for SL genes are phylogenetically related, one might hypothesize that this arrangement is the result of an ancestral insertion of 5S rRNA genes into the tandemly repeated SL gene family of trypanosomes. Here, we use the types of 5S rRNA genes found associated with SL genes, the flanking regions of the inserted 5S rRNA genes and the position of these insertions to show that most of the 5S rRNA genes found within SL gene repeat units of trypanosome species were not acquired from a common ancestor but are the results of independent insertions. These multiple 5S rRNA genes insertion events in trypanosomes are likely the result of frequent founder events in different hosts and/or geographical locations in species having short generation times.

  7. Phylogeny and Morphological Variability of Trypanosomes from African Pelomedusid Turtles with Redescription of Trypanosoma mocambicum Pienaar, 1962.

    Science.gov (United States)

    Dvořáková, Nela; Čepička, Ivan; Qablan, Moneeb A; Gibson, Wendy; Blažek, Radim; Široký, Pavel

    2015-12-01

    Little is known about host specificity, genetic diversity and phylogenetic relationships of African turtle trypanosomes. Using PCR targeting the SSU rRNA gene, we detected trypanosomes in 24 of 134 (17.9%) wild caught African pelomedusid turtles: Pelusios upembae (n=14), P. bechuanicus (n=1), P. rhodesianus (n=3) and P. subniger (n=6). Mixed infection of Trypanosoma species was confirmed by PCR in three specimens of P. upembae, and in one specimen each of P. bechuanicus, P. rhodesianus, and P. subniger. Microscopic examination of stained blood smears revealed two distinct forms (broad and slender) of trypomastigotes. The broad form coincided in morphology with T. mocambicumPienaar, 1962. Accordingly, we have designated this form as the neotype of T. mocambicum. In phylogenetic analysis of the SSU rRNA gene, all the new turtle trypanosome sequences grouped in a single clade within the strongly supported "aquatic" clade of Trypanosoma species. The turtle trypanosome clade was further subdivided into two subclades, which did not correlate with host turtle species or trypanosome morphology. This study provides the first sequence data of Trypanosoma species isolated from freshwater turtles from tropical Africa and extends knowledge on diversity of trypanosomes in the Afrotropical zoogeographical realm.

  8. In search for a compromise between biodiversity conservation and human health protection in restoration of fly ash deposits: effect of anti-dust treatments on five groups of arthropods.

    Science.gov (United States)

    Tropek, Robert; Cerna, Ilona; Straka, Jakub; Kocarek, Petr; Malenovsky, Igor; Tichanek, Filip; Sebek, Pavel

    2016-07-01

    Recently, fly ash deposits have been revealed as a secondary refuge of critically endangered arthropods specialised on aeolian sands in Central Europe. Simultaneously, these anthropogenic habitats are well known for their negative impact on human health and the surrounding environment. The overwhelming majority of these risks are caused by wind erosion, the substantial decreasing of which is thus necessary. But, any effects of anti-dust treatments on endangered arthropods have never been studied. We surveyed communities of five arthropod groups (wild bees and wasps, leafhoppers, spiders, hoverflies and orthopteroid insects) colonising three fly ash deposits in the western Czech Republic. We focused on two different anti-dust treatments (~70 and 100 % cover of fly ash by barren soil) and their comparison with a control of bare fly ash. Altogether, we recorded 495 species, including 132 nationally threatened species (eight of them were considered to be extinct in the country) and/or 30 species strictly specialised to drift sands. Bees and wasps and leafhoppers contained the overwhelming majority of species of the highest conservation interest; a few other important records were also in spiders and orthopteroids. Total soil cover depleted the unique environment of fly ash and thus destroyed the high conservation potential of the deposits. On the other hand, partial coverage (with ~30 % of bare fly ash) still offered habitats for many of the most threatened species, as we showed by both regression and multivariate analyses, with a decrease of wind erosion. This topic still needs much more research interest, but we consider mosaic-like preservation of smaller spots of fly ash as one of the possible compromises between biodiversity and human health.

  9. Disappearance of some human African trypanosomiasis transmission foci in Zambia in the absence of a tsetse fly and trypanosomiasis control program over a period of forty years.

    Science.gov (United States)

    Mwanakasale, Victor; Songolo, Peter

    2011-03-01

    We conducted a situation analysis of human African trypanosomiasis (HAT) in Zambia from January 2000 to April 2007. The aim of this survey was to identify districts in Zambia that were still recording cases of HAT. Three districts namely, Mpika, Chama, and Chipata were found to be still reporting cases of HAT and thus lay in HAT transmission foci in North Eastern Zambia. During the period under review, 24 cases of HAT were reported from these three districts. We thereafter reviewed literature on the occurrence of HAT in Zambia from the early 1960s to mid 1990s. This revealed that HAT transmission foci were widespread in Western, North Western, Lusaka, Eastern, Luapula, and Northern Provinces of Zambia during this period. In this article we have tried to give possible reasons as to why the distribution of HAT transmission foci is so different between before and after 2000 when there has been no active national tsetse fly and trypanosomiasis control program in Zambia.

  10. Bovine trypanosomosis and its fly vectors in three selected settlement areas of Hawa-Gelan district, western Ethiopia

    Directory of Open Access Journals (Sweden)

    Kumela Lelisa

    2014-02-01

    Full Text Available A cross-sectional study aimed at investigating the species diversity of fly vectors and estimating the prevalence of bovine trypanosomosis was carried out from October 2009 to May 2010 in selected settlement areas of the Hawa-Gelan district in the western Wollega zone of Ethiopia. Standard methods of sampling and identification were employed for both entomological and parasitological examination. Three species of the genus Glossina (Glossina pallidipes, Glossina morsitans submorsitans and Glossina fuscipes and two genera of biting flies (Stomoxys and Tabanus were caught and identified. The overall apparent density of Glossina species caught was 10.5 flies per trap per day, with a higher proportion of female flies (57.2%. Out of a total 389 cattle examined, 42 (10.8%; 95% CI: 7.89% – 14.3% were found infected with trypanosomes. Three trypanosome species were detected in the study area, namely Trypanosoma congolense (54.8%, Trypanosoma brucei (23.8% and Trypanosoma vivax (21.4%. The prevalence of trypanosomosis was found to be significantly (p < 0.05 higher in cattle with poor body condition. There was an association between mean packed cell volume (PCV and the occurrence of parasitaemia (χ2 = 49.5, p < 0.05. About 95.2% of cattle that were positive for trypanosomes had a PCV less than the lower limit for cattle. Considering the current result, bovine trypanosomosis seems to be a serious constraint for agricultural activities in the settlement areas of the Hawa-Gelan district and seems to be associated with the presence of Glossina species. Therefore, application of control methods through community involvement to reduce the Glossina species infestation level is likely to increase animal productivity.

  11. Estimating Orientation of Flying Fruit Flies.

    Directory of Open Access Journals (Sweden)

    Xi En Cheng

    Full Text Available The recently growing interest in studying flight behaviours of fruit flies, Drosophila melanogaster, has highlighted the need for developing tools that acquire quantitative motion data. Despite recent advance of video tracking systems, acquiring a flying fly's orientation remains a challenge for these tools. In this paper, we present a novel method for estimating individual flying fly's orientation using image cues. Thanks to the line reconstruction algorithm in computer vision field, this work can thereby focus on the practical detail of implementation and evaluation of the orientation estimation algorithm. The orientation estimation algorithm can be incorporated into tracking algorithms. We rigorously evaluated the effectiveness and accuracy of the proposed algorithm by running experiments both on simulation data and on real-world data. This work complements methods for studying the fruit fly's flight behaviours in a three-dimensional environment.

  12. Best-bet integrated strategies for containing drug-resistant trypanosomes in cattle

    Directory of Open Access Journals (Sweden)

    Mungube Erick O

    2012-08-01

    Full Text Available Abstract Background African animal trypanosomosis is a major constraint to the rearing of productive livestock in the sub-humid Sudan-Sahel zone of West Africa where cotton is grown. Trypanosomosis is mainly controlled using trypanocidal drugs, but the effective use of drugs is threatened by the development of widespread resistance. This study tested integrated best-bet strategies for containment and/ or reversal of trypanocide resistance in villages in south-east Mali where resistance has been reported. Methods Four sentinel villages each from an intervention area (along the road from Mali to Burkina Faso and a control area (along the road from Mali to Côte d’Ivoire were selected for the study. Tsetse control was based on deltamethrin-treated stationary attractive devices and targeted cattle spraying between March 2008 and November 2009. Trypanosome-positive cattle were selectively treated with 3.5 mg/kg diminazene aceturate. Strategic helminth control using 10 mg/kg albendazole was also undertaken. During the intervention, tsetse densities along drainage lines, trypanosome infections and faecal egg counts in risk cattle (3 to 12 months of age were monitored. Results Catch reductions of 66.5 % in Glossina palpalis gambiensis and 90 % in G. tachinoides were observed in the intervention area. Trypanosome prevalence was significantly (p  0.05. Further studies are required before confirming the existence of albendazole resistant strongyles in the study area. Conclusion Integration of best-bet strategies in areas of multiple drug-resistance is expected to reduce trypanosome infection risk thus contributing to containment of trypanocidal drug resistance. Integrated best-bet strategies could therefore be considered a viable trypanosomosis control option especially in areas where multiple drug-resistance has been reported.

  13. Application of field methods to assess isometamidium resistance of trypanosomes in cattle in western Ethiopia

    DEFF Research Database (Denmark)

    Tewelde, N.; Abebe, G.; Eisler, M.;

    2004-01-01

    the proportion of infections during an 8-week follow-up period and the ratio of mean hazards in an isometamidium treated versus untreated group, provided consistent results across the three villages. In Burka village, both indices demonstrated the presence of isometamidium resistance trypanosome infections while......, in Cheleleki and Kolu villages, both indices did not indicate significant levels of resistance. There were significant differences between the Kaplan-Meier survival estimates of the control and treatment groups in Cheleleki (P 0.05)....

  14. Flying insects and Campylobacter

    DEFF Research Database (Denmark)

    Hald, Birthe; Sommer, Helle Mølgaard; Skovgård, Henrik

    Campylobacter in flies Flies of the Muscidae family forage on all kind of faeces – various fly species have different preferences. M domestica prefer pigs, horses and cattle faeces, animals which are all known to frequently excrete Campylobacter. As a result, the insects pick up pathogenic micro...... organisms, which may collect on their bodies or survive passage through the fly gut. Campylobacter and other pathogens are then easily transferred to other surfaces, for instance peoples food – or to broiler houses where they may be swallowed by chickens or contaminate the environment. On a large material...... of several species of flies collected outside broiler houses, merely ~1% of the flies were found Campylobacter positive. However, the prevalence varied considerably with fly species, time of the year, and availability of Campylobacter sources. Influx of flies to broiler houses As the influx of flies...

  15. Flying insects and Campylobacter

    DEFF Research Database (Denmark)

    Hald, Birthe; Sommer, Helle Mølgaard; Skovgård, Henrik

    to broiler houses may be counted in thousands per broiler rotation during summer periods, even a low prevalence of Campylobacter positive flies constitute a risk of introduction of Campylobacter to the chickens. M. domestica – the house fly is the most important vector fly for Campylobacter transmission...... organisms, which may collect on their bodies or survive passage through the fly gut. Campylobacter and other pathogens are then easily transferred to other surfaces, for instance peoples food – or to broiler houses where they may be swallowed by chickens or contaminate the environment. On a large material...... of several species of flies collected outside broiler houses, merely ~1% of the flies were found Campylobacter positive. However, the prevalence varied considerably with fly species, time of the year, and availability of Campylobacter sources. Influx of flies to broiler houses As the influx of flies...

  16. The human homologue of the Drosophila melanogaster flightless-I gene (fliI) maps within the Smith-Magenis microdeletion critical region in 17p11.2

    Energy Technology Data Exchange (ETDEWEB)

    Chen, K.S.; Nguyen, D.; Greenberg, F. [Baylor College of Medicing, Houston, TX (United States)] [and others

    1994-09-01

    The Smith-Magenis syndrome (SMS) appears to be a contiguous gene deletion syndrome associated with a proximal deletion of the short arm of chromosome 17 in band p11.2. The spectrum of clinical findings includes short stature, brachydactyly, developmental delay, dysmorphic features, sleep disturbances and behavioral problems. The complex phenotypic features suggest deletion of several contiguous genes. However, to date no protein encoding gene has been mapped to the SMS critical region. Recently, Campbell described the cloning and characterization of D. melanogaster fli cDNAs and of homologous cDNAs from caenorhabditis elegans and from humans. Mutations in fliI result in loss of flight ability and, when severe, cause lethality due to incomplete cellularization with subsequent abnormal gastrulation. The amino acid sequence deduced from the FLI cDNA has 52% similarity to the human gelsolin protein and also has a N-terminal leucine-rich domain with 16 consecutive leucine-rich repeats (LRR). Here, we demonstrate that the human homologue (FLI) maps within the SMS critical region. Genomic cosmids were used as probes for fluorescence in situ hybridization (FISH) and localized this gene to the 17p11.2 region. Somatic cell hybrids and/or FISH analysis of lymphoblastoid cell lines form 12 SMS patients demonstrate that one copy of the FLI gene is deleted in all SMS patients analyzed with the common deletion. Further studies are required to determine if haploinsufficiency of FLI or other as yet unidentified genes is important for the expression of the SMS phenotype.

  17. Phosphatidylethanolamine is the donor of the terminal phosphoethanolamine group in trypanosome glycosylphosphatidylinositols.

    Science.gov (United States)

    Menon, A K; Eppinger, M; Mayor, S; Schwarz, R T

    1993-01-01

    A variety of eukaryotic cell surface proteins, including the variant surface glycoproteins of African trypanosomes, rely on a covalently attached lipid, glycosylphosphatidylinositol (GPI), for membrane attachment. GPI anchors are synthesized in the endoplasmic reticulum by stepwise glycosylation of phosphatidylinositol (via UDP-GlcNAc and dolichol-P-mannose) followed by the addition of phosphoethanolamine. The experiments described in this paper are aimed at identifying the biosynthetic origin of the terminal phosphoethanolamine group. We show that trypanosome GPIs can be labelled via CDP-[3H]ethanolamine or [beta-32P]CDP-ethanolamine in a cell-free system, indicating that phosphoethanolamine is acquired en bloc. In pulse-chase experiments with CDP-[3H]ethanolamine we show that the GPI phosphoethanolamine is not derived directly from CDP-ethanolamine, but instead from a relatively stable metabolite, such as phosphatidylethanolamine (PE), generated from CDP-ethanolamine in the cell-free system. To test the possibility that PE is the immediate donor of the GPI phosphoethanolamine moiety, we describe metabolic labelling experiments with [3H]serine and show that GPIs can be labelled in the absence of detectable radiolabelled CDP-ethanolamine, presumably via [3H]PE generated from [3H]phosphatidylserine (PS). The data support the proposal that the terminal phosphoethanolamine group in trypanosome GPIs is derived from PE. PMID:8491183

  18. Optimal strategies for controlling riverine tsetse flies using targets: a modelling study.

    Directory of Open Access Journals (Sweden)

    Glyn A Vale

    2015-03-01

    Full Text Available Tsetse flies occur in much of sub-Saharan Africa where they transmit the trypanosomes that cause the diseases of sleeping sickness in humans and nagana in livestock. One of the most economical and effective methods of tsetse control is the use of insecticide-treated screens, called targets, that simulate hosts. Targets have been ~1 m2, but recently it was shown that those tsetse that occupy riverine situations, and which are the main vectors of sleeping sickness, respond well to targets only ~0.06 m2. The cheapness of these tiny targets suggests the need to reconsider what intensity and duration of target deployments comprise the most cost-effective strategy in various riverine habitats.A deterministic model, written in Excel spreadsheets and managed by Visual Basic for Applications, simulated the births, deaths and movement of tsetse confined to a strip of riverine vegetation composed of segments of habitat in which the tsetse population was either self-sustaining, or not sustainable unless supplemented by immigrants. Results suggested that in many situations the use of tiny targets at high density for just a few months per year would be the most cost-effective strategy for rapidly reducing tsetse densities by the ~90% expected to have a great impact on the incidence of sleeping sickness. Local elimination of tsetse becomes feasible when targets are deployed in isolated situations, or where the only invasion occurs from populations that are not self-sustaining.Seasonal use of tiny targets deserves field trials. The ability to recognise habitat that contains tsetse populations which are not self-sustaining could improve the planning of all methods of tsetse control, against any species, in riverine, savannah or forest situations. Criteria to assist such recognition are suggested.

  19. Use Of Fly Iarvae In Space Agriculture

    Science.gov (United States)

    Katayama, Naomi; Mitsuhashi, Jun; Hachiya, Natumi; Miyashita, Sachiko; Hotta, Atuko

    The concept of space agriculture is full use of biological and ecological components ot drive materials recycle loop. In an ecological system, producers, consumers and decomposers are its member. At limited resources acailable for space agriculture, full use of members' function is required to avoid food shortage and catastrophe.Fly is categrized to a decomposer at its eating excreta and rotten materials. However, is it could be edible, certainly it is eaten in several food culture of the world, it functions as a converter of inedible biomass ot edible substance. This conversion enhances the efficiency of usage of resource that will be attributed to space agriculture. In this context, we examine the value of melon fly, Dacus cucurbitae, as a candidate fly species ofr human food. Nutrients in 100g of melon fly larvae were protein 12g, lipid 4.6g Fe 4.74mg, Ca 275mg, Zn 6.37mg, Mn 4.00mg. Amino acids compositon in 100g of larvae was glutamic acid 1.43g and aspartic acid 1.12g. Because of high contents of these amino acids taste of fly larva might be good. Life time of adult melon fly is one to two month, and lays more than 1,000 eggs in total during the life. Larvae hatch after one to two days, and metamorphose after 8 to 15 days to pupae. Srxual maturity is reached after 22 days the earliest from it egg. Sixteen generations could be succeeded in a year for melon fly at maximum. The rate of proliferation of fly is quite high compared to silkworm that can have 8.7 generations per year. The wide food habit of fly, compared to mulberry leaf for silkworm, is another advantage to choose fly for entomophage. Rearing technology of melon fly is well established, since large scaled production of sterile male fly has been conducted in order ot exterminate melon fly in the field. Feeding substance for melon fly larvae in production line is a mixture of wheat, bran, raw sugar, olara, beer yeast, tissue paper, and additive chemicals. A 1 kg of feed substance can be converted to

  20. The human homologue of the Drosophila melanogaster flightless-I gene (fliI) maps within the Smith-Magenis microdeletion critical region in 17p11.2

    Energy Technology Data Exchange (ETDEWEB)

    Chen, K.S.; Gunaratne, P.H.; Greenberg, F.; Shaffer, L.G.; Lupski, J.R. [Baylor College of Medicine, Houston, TX (United States); Hoheisel, J.D. [German Cancer Research Center, Heidelberg (Germany); Young, I.G.; Miklos, G.L.G.; Campbell, H.D. [Australian National Univ., Canberra (Australia)

    1995-01-01

    The Smith-Magenis syndrome (SMS) appears to be a contiguous-gene-deletion syndrome associated with a proximal deletion of the short arm of chromosome 17 in band p11.2. The spectrum of clinical findings includes short stature, brachydactyly, developmental delay, dysmorphic features, sleep disturbances, and behavioral problems. The complex phenotypic features suggest deletion of several contiguous genes. However, to date, no protein-encoding gene has been mapped to the SMS critical region. Recently, the Drosophila melanogaster flightless-I gene, fliI, and the homologous human cDNA have been isolated. Mutations in fliI result in loss of flight ability and, when severe, cause lethality due to incomplete cellularization with subsequent abnormal gastrulation. Here, we demonstrate that the human homologue (FLI) maps within the SMS critical region. Genomic cosmids were used as probes for FISH, which localized this gene to the 17p11.2 region. Somatic-cell hybrid-panel mapping further localized this gene to the SMS critical region. Southern blot analysis of somatic-cell hybrids and/or FISH analysis of lymphoblastoid cell lines from 12 SMS patients demonstrates the deletion of one copy of FLI in all SMS patients analyzed. 47 refs., 4 figs., 1 tab.

  1. Bloodstream form pre-adaptation to the tsetse fly in Trypanosoma brucei.

    Science.gov (United States)

    Rico, Eva; Rojas, Federico; Mony, Binny M; Szoor, Balazs; Macgregor, Paula; Matthews, Keith R

    2013-01-01

    African trypanosomes are sustained in the bloodstream of their mammalian hosts by their extreme capacity for antigenic variation. However, for life cycle progression, trypanosomes also must generate transmission stages called stumpy forms that are pre-adapted to survive when taken up during the bloodmeal of the disease vector, tsetse flies. These stumpy forms are rather different to the proliferative slender forms that maintain the bloodstream parasitaemia. Firstly, they are non proliferative and morphologically distinct, secondly, they show particular sensitivity to environmental cues that signal entry to the tsetse fly and, thirdly, they are relatively robust such that they survive the changes in temperature, pH and proteolytic environment encountered within the tsetse midgut. These characteristics require regulated changes in gene expression to pre-adapt the parasite and the use of environmental sensing mechanisms, both of which allow the rapid initiation of differentiation to tsetse midgut procyclic forms upon transmission. Interestingly, the generation of stumpy forms is also regulated and periodic in the mammalian blood, this being governed by a density-sensing mechanism whereby a parasite-derived signal drives cell cycle arrest and cellular development both to optimize transmission and to prevent uncontrolled parasite multiplication overwhelming the host. In this review we detail recent developments in our understanding of the molecular mechanisms that underpin the production of stumpy forms in the mammalian bloodstream and their signal perception pathways both in the mammalian bloodstream and upon entry into the tsetse fly. These discoveries are discussed in the context of conserved eukaryotic signaling and differentiation mechanisms. Further, their potential to act as targets for therapeutic strategies that disrupt parasite development either in the mammalian bloodstream or upon their transmission to tsetse flies is also discussed.

  2. Sand Flies and Their Control Methods.

    Science.gov (United States)

    Çetin, Hüseyin; Özbel, Yusuf

    2017-06-01

    The main aim of managing arthropod vectors that carry the disease agents is interrupting the infection cycle. Therefore, the management of the disease implies that all precautions related to all elements (i.e., human, arthropod vector, and reservoir) in the infection cycle need to be taken. There are important points that need to be considered while dealing with sand flies (Diptera: Psychodidae: Phlebotominae), which in many regions worldwide, particularly in tropical and subtropical areas, are vectors of diseases such as leishmaniasis and sand fly fever and are the arthropods of the infection cycle. Because the larval control of the sand flies is very difficult and almost impossible, the management is mainly conducted for the adults. The most effective strategy for reducing both sand fly fever and leishmaniasis is managing sand flies, particularly in areas where humans are located. In this review, the morphology, biology, and taxonomy of sand flies; the integrated fighting and management methods such as insecticide-impregnated bed nets and use of curtains, zooprophylaxis, indoor and outdoor residual applications, larvicides, repellents, and insecticide-impregnated dog collars; and data regarding many issues such as insecticide resistance in sand flies have been emphasized on in the review.

  3. Effects of 3-chloro-phenyl-1,4-dihydropyridine derivatives on Trypanosome cruzi epimastigotes.

    Science.gov (United States)

    Maya, J D; Morello, A; Repetto, Y; Tellez, R; Rodriguez, A; Zelada, U; Puebla, P; Caballero, E; Medarde, M; Núñez-Vergara, L J; Squella, J A; Bontá, M; Bollo, S; San Feliciano, A

    2000-01-01

    A series of 3-chloro-phenyl-1,4-dihydropyridine derivatives produced different degrees of inhibition of parasite growth and respiration on clone Brener, LQ and Tulahuen strains of Trypanosome cruzi epimastigotes. Respiratory chain inhibition appears to be a posible determinant of the trypanosomicidal activity of this compounds. No difference in the action of these derivatives was found among the different parasite strains. For comparative purposes, the inhibitory effects of felodipine and nicardipine are also reported. A good correlation between toxic effects and the easiness of oxidation of the dihydripyridine ring was found. The presence of a fused ring on the dihydropyridine moiety significantly diminished the inhibitory effects.

  4. Mutations in the mitochondrial methionyl-tRNA synthetase cause a neurodegenerative phenotype in flies and a recessive ataxia (ARSAL in humans.

    Directory of Open Access Journals (Sweden)

    Vafa Bayat

    Full Text Available An increasing number of genes required for mitochondrial biogenesis, dynamics, or function have been found to be mutated in metabolic disorders and neurological diseases such as Leigh Syndrome. In a forward genetic screen to identify genes required for neuronal function and survival in Drosophila photoreceptor neurons, we have identified mutations in the mitochondrial methionyl-tRNA synthetase, Aats-met, the homologue of human MARS2. The fly mutants exhibit age-dependent degeneration of photoreceptors, shortened lifespan, and reduced cell proliferation in epithelial tissues. We further observed that these mutants display defects in oxidative phosphorylation, increased Reactive Oxygen Species (ROS, and an upregulated mitochondrial Unfolded Protein Response. With the aid of this knowledge, we identified MARS2 to be mutated in Autosomal Recessive Spastic Ataxia with Leukoencephalopathy (ARSAL patients. We uncovered complex rearrangements in the MARS2 gene in all ARSAL patients. Analysis of patient cells revealed decreased levels of MARS2 protein and a reduced rate of mitochondrial protein synthesis. Patient cells also exhibited reduced Complex I activity, increased ROS, and a slower cell proliferation rate, similar to Drosophila Aats-met mutants.

  5. Fly ash carbon passivation

    Science.gov (United States)

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14

    A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

  6. Crovirin, a Snake Venom Cysteine-Rich Secretory Protein (CRISP) with Promising Activity against Trypanosomes and Leishmania

    Science.gov (United States)

    Adade, Camila M.; Carvalho, Ana Lúcia O.; Tomaz, Marcelo A.; Costa, Tatiana F. R.; Godinho, Joseane L.; Melo, Paulo A.; Lima, Ana Paula C. A.; Rodrigues, Juliany C. F.; Zingali, Russolina B.; Souto-Padrón, Thaïs

    2014-01-01

    Background The neglected human diseases caused by trypanosomatids are currently treated with toxic therapy with limited efficacy. In search for novel anti-trypanosomatid agents, we showed previously that the Crotalus viridis viridis (Cvv) snake venom was active against infective forms of Trypanosoma cruzi. Here, we describe the purification of crovirin, a cysteine-rich secretory protein (CRISP) from Cvv venom with promising activity against trypanosomes and Leishmania. Methodology/Principal Findings Crude venom extract was loaded onto a reverse phase analytical (C8) column using a high performance liquid chromatographer. A linear gradient of water/acetonitrile with 0.1% trifluoroacetic acid was used. The peak containing the isolated protein (confirmed by SDS-PAGE and mass spectrometry) was collected and its protein content was measured. T. cruzi trypomastigotes and amastigotes, L. amazonensis promastigotes and amastigotes and T. brucei rhodesiense procyclic and bloodstream trypomastigotes were challenged with crovirin, whose toxicity was tested against LLC-MK2 cells, peritoneal macrophages and isolated murine extensor digitorum longus muscle. We purified a single protein from Cvv venom corresponding, according to Nano-LC MS/MS sequencing, to a CRISP of 24,893.64 Da, henceforth referred to as crovirin. Human infective trypanosomatid forms, including intracellular amastigotes, were sensitive to crovirin, with low IC50 or LD50 values (1.10–2.38 µg/ml). A considerably higher concentration (20 µg/ml) of crovirin was required to elicit only limited toxicity on mammalian cells. Conclusions This is the first report of CRISP anti-protozoal activity, and suggests that other members of this family might have potential as drugs or drug leads for the development of novel agents against trypanosomatid-borne neglected diseases. PMID:25330220

  7. Repertoire, genealogy and genomic organization of cruzipain and homologous genes in Trypanosoma cruzi, T. cruzi-like and other trypanosome species.

    Science.gov (United States)

    Lima, Luciana; Ortiz, Paola A; da Silva, Flávia Maia; Alves, João Marcelo P; Serrano, Myrna G; Cortez, Alane P; Alfieri, Silvia C; Buck, Gregory A; Teixeira, Marta M G

    2012-01-01

    Trypanosoma cruzi, the agent of Chagas disease, is a complex of genetically diverse isolates highly phylogenetically related to T. cruzi-like species, Trypanosoma cruzi marinkellei and Trypanosoma dionisii, all sharing morphology of blood and culture forms and development within cells. However, they differ in hosts, vectors and pathogenicity: T. cruzi is a human pathogen infective to virtually all mammals whilst the other two species are non-pathogenic and bat restricted. Previous studies suggest that variations in expression levels and genetic diversity of cruzipain, the major isoform of cathepsin L-like (CATL) enzymes of T. cruzi, correlate with levels of cellular invasion, differentiation, virulence and pathogenicity of distinct strains. In this study, we compared 80 sequences of genes encoding cruzipain from 25 T. cruzi isolates representative of all discrete typing units (DTUs TcI-TcVI) and the new genotype Tcbat and 10 sequences of homologous genes from other species. The catalytic domain repertoires diverged according to DTUs and trypanosome species. Relatively homogeneous sequences are found within and among isolates of the same DTU except TcV and TcVI, which displayed sequences unique or identical to those of TcII and TcIII, supporting their origin from the hybridization between these two DTUs. In network genealogies, sequences from T. cruzi clustered tightly together and closer to T. c. marinkellei than to T. dionisii and largely differed from homologues of T. rangeli and T. b. brucei. Here, analysis of isolates representative of the overall biological and genetic diversity of T. cruzi and closest T. cruzi-like species evidenced DTU- and species-specific polymorphisms corroborating phylogenetic relationships inferred with other genes. Comparison of both phylogenetically close and distant trypanosomes is valuable to understand host-parasite interactions, virulence and pathogenicity. Our findings corroborate cruzipain as valuable target for drugs, vaccine

  8. Trypanosomal histone γH2A and the DNA damage response.

    Science.gov (United States)

    Glover, Lucy; Horn, David

    2012-05-01

    DNA damage and repair in trypanosomatids impacts virulence, drug resistance and antigenic variation but, currently, little is known about DNA damage responses or cell cycle checkpoints in these divergent protozoa. One of the earliest markers of DNA damage in eukaryotes is γH2A(X), a serine phosphorylated histone H2A (variant). Here, we report the identification and initial characterization of γH2A in Trypanosoma brucei. We identified Thr(130) within the replication-dependent histone H2A as a candidate phosphorylation site and found that the abundance of this trypanosomal γH2A increased in vivo in response to DNA damage. Nuclear γH2A foci mark the sites of putative natural replication fork stalling, sites of meganuclease-induced DNA double strand breaks and sites of methyl methanesulphonate-induced DNA damage. Naturally occurring and meganuclease-induced γH2A and RAD51 double-positive repair foci are typically found in S-phase or G(2) nuclei. The results link trypanosomal γH2A, with an unusual histone modification motif, to DNA damage sensing and mitotic checkpoint signaling.

  9. Identification of trypanosomes in wild animals from Southern Cameroon using the polymerase chain reaction (PCR

    Directory of Open Access Journals (Sweden)

    Herder S.

    2002-12-01

    Full Text Available One possible explanation of the maintenance of many historical foci of sleeping sickness in Central Africa could be the existence of a wild animal reservoir. In this study, PCR was used to detect the different trypanosome species present in wild animal captured by hunters in the southern forest belt of Cameroon (Bipindi. Trypanosomes were also detected by a parasitological method (Quantitative buffy coat : QBC. Parasite could not be isolated in culture medium (Kit for in vitro isolation : KIVI. Specific primers of T. brucei s.l., T. congolense forest type, T. congolense savannah type, T. vivax, T. simiae and T. b. gambiense group 1 were used to identify parasites in the blood of 164 animals belonging to 24 different species including ungulates, rodents, pangolins, carnivores, reptiles and primates. Of the 24 studied species, eight were carrying T. b. gambiense group 1. Those parasites pathogenic to man were found in monkeys (Cercocebus torquatus and Cercopithecus nictitans, in ungulates (Cephalophus dorsalis and C. monticola, in carnivores (Nandinia binotata and Genetta servalina and in rodents (Cricetomys gambianus and Atherurus africanus. 13 species (54 % were carrying T. brucei s.l. identified as non-gambiense group 1.

  10. Molecular identification of trypanosome species in trypanotolerant cattle from the south of Gabon

    Directory of Open Access Journals (Sweden)

    Maganga Gaël Darren

    2017-01-01

    Full Text Available The aim of this study was to provide information on trypanosome species infecting trypanotolerant cattle from southern Gabon. The study was conducted on 224 trypanotolerant cattle from three regions located in southern Gabon, using ITS1 primer-based PCR. Seventy-two (32% N’dama cattle were found polymerase chain reaction (PCR positive with trypanosomes. The overall prevalence of trypanosomosis was 57% (63/110, 4% (4/100, and 36% (5/14 in the Gala section of the Nyanga ranch, the Miyama ranch, and Ossiele, respectively. Trypanosoma congolense and Trypanosoma vivax were identified. In Gala section and Ossiele, T. congolense and T. vivax were found. In the Miyama ranch, only T. vivax was identified. Mixed infections were also found. The forest (9% and savannah (63% subgroups of T. congolense were identified. The presence of the two subgroups was detected in 16 out of 56 cattle (29%. T. congolense and T. vivax would appear to be the main agents responsible for bovine trypanosomosis in southern Gabon. Although trypanotolerant, N’dama cattle may serve as a reservoir, and this should be further studied. On the other hand, these trypanotolerant cattle can be reared in such tsetse infested areas, which gives them an advantage compared to other trypanosensitive breeds, and this shows that they represent a key factor in biodiversity which has to be promoted.

  11. The potential impact of native Australian trypanosome infections on the health of koalas (Phascolarctos cinereus).

    Science.gov (United States)

    McInnes, L M; Gillett, A; Hanger, J; Reid, S A; Ryan, U M

    2011-06-01

    Whole blood collected from koalas admitted to the Australian Zoo Wildlife Hospital (AZWH), Beerwah, QLd, Australia, during late 2006-2009 was tested using trypanosome species-specific 18S rDNA PCRs designed to amplify DNA from Trypanosoma irwini, T. gilletti and T. copemani. Clinical records for each koala sampled were reviewed and age, sex, blood packed cell volume (PCV), body condition, signs of illness, blood loss, trauma, chlamydiosis, bone marrow disease, koala AIDS and hospital admission outcome ('survival'/ 'non-survival') were correlated with PCR results. Overall 73.8% (439/595) of the koalas were infected with at least 1 species of trypanosome. Trypanosoma irwini was detected in 423/595 (71.1%), T. gilletti in 128/595 (21.5%) and T. copemani in 26/595 (4.4%) of koalas. Mixed infections were detected in 125/595 (21%) with co-infections of T. irwini and T. gilletti (101/595, 17%) being most common. There was a statistical association between infection with T. gilletti with lower PCV values and body condition scores in koalas with signs of chlamydiosis, bone marrow disease or koala AIDS. No association between T. gilletti infection and any indicator of health was observed in koalas without signs of concurrent disease. This raises the possibility that T. gilletti may be potentiating other disease syndromes affecting koalas.

  12. Identification of trans-sialidases as a common mediator of endothelial cell activation by African trypanosomes.

    Directory of Open Access Journals (Sweden)

    Zeinab Ammar

    Full Text Available Understanding African Trypanosomiasis (AT host-pathogen interaction is the key to an "anti-disease vaccine", a novel strategy to control AT. Here we provide a better insight into this poorly described interaction by characterizing the activation of a panel of endothelial cells by bloodstream forms of four African trypanosome species, known to interact with host endothelium. T. congolense, T. vivax, and T. b. gambiense activated the endothelial NF-κB pathway, but interestingly, not T. b. brucei. The parasitic TS (trans-sialidases mediated this NF-κB activation, remarkably via their lectin-like domain and induced production of pro-inflammatory molecules not only in vitro but also in vivo, suggesting a considerable impact on pathogenesis. For the first time, TS activity was identified in T. b. gambiense BSF which distinguishes it from the subspecies T. b. brucei. The corresponding TS were characterized and shown to activate endothelial cells, suggesting that TS represent a common mediator of endothelium activation among trypanosome species with divergent physiopathologies.

  13. Anti-trypanosomal effect of Peristrophe bicalyculata extract on Trypanosoma brucei brucei-infected rats

    Institute of Scientific and Technical Information of China (English)

    Abdulazeez Mansurah Abimbola; Ibrahim Abdulrazak Baba; Edibo Zakari Yenusa; Sidali Joseph Omanibe; Idris Habeeb Oladimeji

    2013-01-01

    Objective: To investigate the in vitro and in vivo effect of whole plant extracts of Peristrophe bicalyculata on Trypanosoma brucei brucei-infected rats. Methods: The experiment was divided into two phases: In the first phase, the anti-trypanosomal activity of the hot water, cold water, methanol and butanol extracts of the whole plant were determined by incubating with Trypanosoma brucei brucei. The cold water extract was partially-purified and the anti-trypanosomal activity of the fractions determined. In the second phase, Trypanosoma brucei brucei-infected rats were treated with fraction 2c for nine days. Packed cell volume (PCV), high density lipoprotein (HDL), low density lipoprotein (LDL), total cholesterol (TC), triacylglycerol (TAG), aspartate aminotransferase, alanine aminotransferases (ALT), alkaline phosphatase (ALP), total and direct bilirubin levels were determined at the end of the experiment. Results:Cold water extract immobilized 90%of the parasites after 60 min of incubation, and fraction 2c completely immobilized the parasites after 35 min. It significantly increased PCV in Trypanosoma brucei brucei-infected rats. Decreased TC, TAG, HDL and LDL levels of infected rats increased significantly when rats were treated with the fraction, while elevated levels of total bilirubin and ALT also decreased. The difference in urea, direct bilirubin and ALP was not significant when infected rats were compared to rats in other groups. Conclusions:The ability of the plant to ameliorate the infection-induced biochemical changes calls for detailed investigation of the potentials of the plant for antitrypanosomiasis drug delivery.

  14. Formation Flying Concept Issues

    Directory of Open Access Journals (Sweden)

    M. V. Palkin

    2015-01-01

    Full Text Available The term “formation flying” implies coordinated movement of at least two satellites on coplanar and non-coplanar orbits with a maximum distance between them being much less than the length of the orbit. Peculiarities of formation flying concept also include:- automatic coordination of satellites;- sub-group specialization of formation flying satellites;- equipment and data exchange technology unification in each specialized group or subgroup.Formation flying satellites can be classified according to the configuration stability level (order (array, cluster («swarm», intergroup specialization rules («central satellite», «leader», «slave», manoeuvrability («active» and «passive» satellites.Tasks of formation flying include:- experiments with payload, distributed in formation flying satellites;- various near-earth space and earth-surface research;- super-sized aperture antenna development;- land-based telescope calibration;- «space advertisement» (earth-surface observable satellite compositions of a logotype, word, etc.;- orbital satellite maintenance, etc.Main issues of formation flying satellite system design are:- development of an autonomous satellite group manoeuvring technology;- providing a sufficient characteristic velocity of formation flying satellites;- ballistic and navigation maintenance for satellite formation flying;- technical and economic assessment of formation flying orbital delivery and deployment;- standardization, unification, miniaturization and integration of equipment;- intergroup and intersatellite function redistribution.

  15. Properties Of A Midgut Trypanolysin From The Tsetse Fly Glossina Morsitans Morsitans

    Directory of Open Access Journals (Sweden)

    Mahamat H.Abakar

    2015-08-01

    Full Text Available The properties of a bloodmeal-induced trypanolysin from the midgut of the tsetse G. m. morsitans was studied in vitro. The semi-purified trypanolysin from twice-fed tsetse had the highest trypanolysin activity against bloodstream trypanosomes followed by those once-fed and the unfed flies. Serum found to display trypanolysin activity. The trypanolysin had no trypsin activity nor even affected by the enzyme. In addition trypanolysin was not affected by protease inhibitors such as soy bean trypsin inhibitor STI N-a-p-Tosyl-L-lysine chromethyl ketone TLCK phenylmethyl sulphonyl fluoride PMSF diisopropyl fluoro-phosphate DFP and tosylamide-2-phenylethyl chloromethyl ketone TPCK. However the activity was completely inhibited by diethyl pyrocarbonate DEPC and partially by aprotinin. The induction of trypanolysin activity by bloodmeal increased gradually reaching a peak at 72-120 h after the bloodmeal and then decreased rapidly with only 25 of the peak activity remaining after 192 h. The trypanolysin was inactivated during storage at 27amp8451 and 4amp8451 after 15 and 32 days respectively. Similarly heating the midguts trypanolysin to 60 - 80amp8451 led to loss of activity. On the other hand 50amp8451 was found to be the optimum temperature for trypanolysin activity. The activity was also unstable by freeze-thaw at 80amp8451 -70amp8451 -20amp8451 and 0amp8451 after 33 41 55 and 63 days respectively. Trypanolysin caused lyses of bloodstream-form T. b. brucei while the procyclic trypanosomes were unaffected. The highest trypanolysin activity in different tsetse species was found with Glossina longipennis followed by Glossina pallidipes Glossina morsitans centralis Glossina fuscipes fuscipes and G. m. morsitans. When the midgut homogenate was separated by anion-exchange chromatography the trypanolysin activity was recovered in the bound fraction. These results suggest that the midgut trypanolysin plays an important role in the establishment of

  16. Ever Fly a Tetrahedron?

    Science.gov (United States)

    King, Kenneth

    2004-01-01

    Few things capture the spirit of spring like flying a kite. Watching a kite dance and sail across a cloud spotted sky is not only a visually appealing experience it also provides a foundation for studies in science and mathematics. Put simply, a kite is an airfoil surface that flies when the forces of lift and thrust are greater than the forces of…

  17. Intravital imaging of a massive lymphocyte response in the cortical dura of mice after peripheral infection by trypanosomes.

    Directory of Open Access Journals (Sweden)

    Jonathan A Coles

    2015-04-01

    Full Text Available Peripheral infection by Trypanosoma brucei, the protozoan responsible for sleeping sickness, activates lymphocytes, and, at later stages, causes meningoencephalitis. We have videoed the cortical meninges and superficial parenchyma of C56BL/6 reporter mice infected with T.b.brucei. By use of a two-photon microscope to image through the thinned skull, the integrity of the tissues was maintained. We observed a 47-fold increase in CD2+ T cells in the meninges by 12 days post infection (dpi. CD11c+ dendritic cells also increased, and extravascular trypanosomes, made visible either by expression of a fluorescent protein, or by intravenous injection of furamidine, appeared. The likelihood that invasion will spread from the meninges to the parenchyma will depend strongly on whether the trypanosomes are below the arachnoid membrane, or above it, in the dura. Making use of optical signals from the skull bone, blood vessels and dural cells, we conclude that up to 40 dpi, the extravascular trypanosomes were essentially confined to the dura, as were the great majority of the T cells. Inhibition of T cell activation by intraperitoneal injection of abatacept reduced the numbers of meningeal T cells at 12 dpi and their mean speed fell from 11.64 ± 0.34 μm/min (mean ± SEM to 5.2 ± 1.2 μm/min (p = 0.007. The T cells occasionally made contact lasting tens of minutes with dendritic cells, indicative of antigen presentation. The population and motility of the trypanosomes tended to decline after about 30 dpi. We suggest that the lymphocyte infiltration of the meninges may later contribute to encephalitis, but have no evidence that the dural trypanosomes invade the parenchyma.

  18. House Fly (Musca domestica L.) Attraction to Insect Honeydew.

    Science.gov (United States)

    Hung, Kim Y; Michailides, Themis J; Millar, Jocelyn G; Wayadande, Astri; Gerry, Alec C

    2015-01-01

    House flies are of major concern as vectors of food-borne pathogens to food crops. House flies are common pests on cattle feedlots and dairies, where they develop in and feed on animal waste. By contacting animal waste, house flies can acquire human pathogenic bacteria such as Escherichia coli and Salmonella spp., in addition to other bacteria, viruses, or parasites that may infect humans and animals. The subsequent dispersal of house flies from animal facilities to nearby agricultural fields containing food crops may lead to pre-harvest food contamination with these pathogens. We hypothesized that odors from honeydew, the sugary excreta produced by sucking insects feeding on crops, or molds and fungi growing on honeydew, may attract house flies, thereby increasing the risk of food crop contamination. House fly attraction to honeydew-contaminated plant material was evaluated using a laboratory bioassay. House flies were attracted to the following plant-pest-honeydew combinations: citrus mealybug on squash fruit, pea aphid on faba bean plants, whitefly on navel orange and grapefruit leaves, and combined citrus mealybug and cottony cushion scale on mandarin orange leaves. House flies were not attracted to field-collected samples of lerp psyllids on eucalyptus plants or aphids on crepe myrtle leaves. Fungi associated with field-collected honeydews were isolated and identified for further study as possible emitters of volatiles attractive to house flies. Two fungal species, Aureobasidium pullulans and Cladosporium cladosporioides, were repeatedly isolated from field-collected honeydew samples. Both fungal species were grown in potato dextrose enrichment broth and house fly attraction to volatiles from these fungal cultures was evaluated. House flies were attracted to odors from A. pullulans cultures but not to those of C. cladosporioides. Identification of specific honeydew odors that are attractive to house flies could be valuable for the development of improved house

  19. House Fly (Musca domestica L. Attraction to Insect Honeydew.

    Directory of Open Access Journals (Sweden)

    Kim Y Hung

    Full Text Available House flies are of major concern as vectors of food-borne pathogens to food crops. House flies are common pests on cattle feedlots and dairies, where they develop in and feed on animal waste. By contacting animal waste, house flies can acquire human pathogenic bacteria such as Escherichia coli and Salmonella spp., in addition to other bacteria, viruses, or parasites that may infect humans and animals. The subsequent dispersal of house flies from animal facilities to nearby agricultural fields containing food crops may lead to pre-harvest food contamination with these pathogens. We hypothesized that odors from honeydew, the sugary excreta produced by sucking insects feeding on crops, or molds and fungi growing on honeydew, may attract house flies, thereby increasing the risk of food crop contamination. House fly attraction to honeydew-contaminated plant material was evaluated using a laboratory bioassay. House flies were attracted to the following plant-pest-honeydew combinations: citrus mealybug on squash fruit, pea aphid on faba bean plants, whitefly on navel orange and grapefruit leaves, and combined citrus mealybug and cottony cushion scale on mandarin orange leaves. House flies were not attracted to field-collected samples of lerp psyllids on eucalyptus plants or aphids on crepe myrtle leaves. Fungi associated with field-collected honeydews were isolated and identified for further study as possible emitters of volatiles attractive to house flies. Two fungal species, Aureobasidium pullulans and Cladosporium cladosporioides, were repeatedly isolated from field-collected honeydew samples. Both fungal species were grown in potato dextrose enrichment broth and house fly attraction to volatiles from these fungal cultures was evaluated. House flies were attracted to odors from A. pullulans cultures but not to those of C. cladosporioides. Identification of specific honeydew odors that are attractive to house flies could be valuable for the

  20. Translation of the edited mRNA for cytochrome b in trypanosome mitochondria

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, Anton; Berry, Edward A.; Maslov, Dmitri A.

    2000-02-01

    The type of RNA editing found in the kinetoplast-mitochondria of trypanosomes and related protozoa, involving uridylate insertions and deletions, creates translatable messenger RNAs (mRNAs) out of nonsense pre-edited RNAs by correcting encoded defects that vary from simple frameshifts to large ''cryptic'' regions. However, any evidence for translation of these mRNAs in the kinetoplast has been missing for decades. We identified a kinetoplast-encoded protein, apocytochrome b, whose mRNA is edited in the 5' region. The determined amino-terminal sequence of the protein coincides with the predicted sequence derived from the edited region, demonstrating that the cognate apocytochrome b mRNA is translated into a functional protein. This finding represents the first direct evidence for a functional translation system in the kinetoplasts.

  1. Growth and differentiation on a trypanosome of the subgenus Schizotrypanum from the bat Phyllostomus hastatus

    Directory of Open Access Journals (Sweden)

    Sônia I. Hamanaka

    1993-12-01

    Full Text Available The effects of temperature, pH, osmolarity and aeration on the growth and differentiation of a trypanosome ofthe subgenus Schizotrypanum isolatedfrom the bat Phyllostomus hastatus were studied. In general, the growth characteristics ofthe flagellate were similar to those of Trypanosoma (Schizotrypanum cruzi. However, the parasite did not growth at 33 or 37C. Increase in the osmolarity and aeration promoted growth at 33C. Significant metacyclogenesis was detected only in the growth condition where maximal growth occured (28C, pH 7.3, 380m0s/kg, in tissue cullure flasks, at the end ofthe exponential growth phase. The begining of the metacyclogenesis process was coincident with most glucose utilization and lowest pH. During metacyclogenesis both culture medium pH and osmolarity increased steadly.

  2. Addition of uridines to edited RNAs in trypanosome mitochondria occurs independently of transcription

    Energy Technology Data Exchange (ETDEWEB)

    Harris, M.E.; Moore, D.R.; Hajduk, S.L. (Univ. of Alabama, Birmingham (USA))

    1990-07-05

    RNA editing is a novel RNA processing event of unknown mechanism that results in the introduction of nucleotides not encoded in the DNA into specific RNA molecules. We have examined the post-transcriptional addition of nucleotides into the mitochondrial RNA of Trypanosoma brucei. Utilizing an isolated organelle system we have determined that addition of uridines to edited RNAs does not require ongoing transcription. Trypanosome mitochondria incorporate CTP, ATP, and UTP into RNA in the absence of transcription. GTP is incorporated into RNA only as a result of the transcription process. Post-transcriptional CTP and ATP incorporation can be ascribed to known enzymatic activities. CTP is incorporated into tRNAs as a result of synthesis or turnover of their 3{prime} CCA sequences. ATP is incorporated into the 3{prime} CCA of tRNAs and into mitochondrial messenger RNAs due to polyadenylation. In the absence of transcription, UTP is incorporated into transcripts known to undergo editing, and the degree of UTP incorporation is consistent with the degree of editing occurring in these transcripts. Cytochrome b mRNAs, which contain a single editing site near their 5{prime} ends, are initially transcribed unedited at that site. Post-transcriptional labeling of cytochrome b mRNAs in the organelle with (alpha-32P)UTP results in the addition of uridines near the 5{prime} end of the RNA but not in a 3{prime} region which lacks an editing site. These results indicate that RNA editing is a post-transcriptional process in the mitochondria of trypanosomes.

  3. Cytosolic peroxidases protect the lysosome of bloodstream African trypanosomes from iron-mediated membrane damage.

    Directory of Open Access Journals (Sweden)

    Corinna Hiller

    2014-04-01

    Full Text Available African trypanosomes express three virtually identical non-selenium glutathione peroxidase (Px-type enzymes which preferably detoxify lipid-derived hydroperoxides. As shown previously, bloodstream Trypanosoma brucei lacking the mitochondrial Px III display only a weak and transient proliferation defect whereas parasites that lack the cytosolic Px I and Px II undergo extremely fast lipid peroxidation and cell lysis. The phenotype can completely be rescued by supplementing the medium with the α-tocopherol derivative Trolox. The mechanism underlying the rapid cell death remained however elusive. Here we show that the lysosome is the origin of the cellular injury. Feeding the px I-II knockout parasites with Alexa Fluor-conjugated dextran or LysoTracker in the presence of Trolox yielded a discrete lysosomal staining. Yet upon withdrawal of the antioxidant, the signal became progressively spread over the whole cell body and was completely lost, respectively. T. brucei acquire iron by endocytosis of host transferrin. Supplementing the medium with iron or transferrin induced, whereas the iron chelator deferoxamine and apo-transferrin attenuated lysis of the px I-II knockout cells. Immunofluorescence microscopy with MitoTracker and antibodies against the lysosomal marker protein p67 revealed that disintegration of the lysosome precedes mitochondrial damage. In vivo experiments confirmed the negligible role of the mitochondrial peroxidase: Mice infected with px III knockout cells displayed only a slightly delayed disease development compared to wild-type parasites. Our data demonstrate that in bloodstream African trypanosomes, the lysosome, not the mitochondrion, is the primary site of oxidative damage and cytosolic trypanothione/tryparedoxin-dependent peroxidases protect the lysosome from iron-induced membrane peroxidation. This process appears to be closely linked to the high endocytic rate and distinct iron acquisition mechanisms of the infective

  4. DNA break site at fragile subtelomeres determines probability and mechanism of antigenic variation in African trypanosomes.

    Directory of Open Access Journals (Sweden)

    Lucy Glover

    2013-03-01

    Full Text Available Antigenic variation in African trypanosomes requires monoallelic transcription and switching of variant surface glycoprotein (VSG genes. The transcribed VSG, always flanked by '70 bp'-repeats and telomeric-repeats, is either replaced through DNA double-strand break (DSB repair or transcriptionally inactivated. However, little is known about the subtelomeric DSBs that naturally trigger antigenic variation in Trypanosoma brucei, the subsequent DNA damage responses, or how these responses determine the mechanism of VSG switching. We found that DSBs naturally accumulate close to both transcribed and non-transcribed telomeres. We then induced high-efficiency meganuclease-mediated DSBs and monitored DSB-responses and DSB-survivors. By inducing breaks at distinct sites within both transcribed and silent VSG transcription units and assessing local DNA resection, histone modification, G2/M-checkpoint activation, and both RAD51-dependent and independent repair, we reveal how breaks at different sites trigger distinct responses and, in 'active-site' survivors, different switching mechanisms. At the active site, we find that promoter-adjacent breaks typically failed to trigger switching, 70 bp-repeat-adjacent breaks almost always triggered switching through 70 bp-repeat recombination (∼60% RAD51-dependent, and telomere-repeat-adjacent breaks triggered switching through loss of the VSG expression site (25% of survivors. Expression site loss was associated with G2/M-checkpoint bypass, while 70 bp-repeat-recombination was associated with DNA-resection, γH2A-focus assembly and a G2/M-checkpoint. Thus, the probability and mechanism of antigenic switching are highly dependent upon the location of the break. We conclude that 70 bp-repeat-adjacent and telomere-repeat-adjacent breaks trigger distinct checkpoint responses and VSG switching pathways. Our results show how subtelomere fragility can generate the triggers for the major antigenic variation mechanisms in

  5. DNA break site at fragile subtelomeres determines probability and mechanism of antigenic variation in African trypanosomes.

    Science.gov (United States)

    Glover, Lucy; Alsford, Sam; Horn, David

    2013-03-01

    Antigenic variation in African trypanosomes requires monoallelic transcription and switching of variant surface glycoprotein (VSG) genes. The transcribed VSG, always flanked by '70 bp'-repeats and telomeric-repeats, is either replaced through DNA double-strand break (DSB) repair or transcriptionally inactivated. However, little is known about the subtelomeric DSBs that naturally trigger antigenic variation in Trypanosoma brucei, the subsequent DNA damage responses, or how these responses determine the mechanism of VSG switching. We found that DSBs naturally accumulate close to both transcribed and non-transcribed telomeres. We then induced high-efficiency meganuclease-mediated DSBs and monitored DSB-responses and DSB-survivors. By inducing breaks at distinct sites within both transcribed and silent VSG transcription units and assessing local DNA resection, histone modification, G2/M-checkpoint activation, and both RAD51-dependent and independent repair, we reveal how breaks at different sites trigger distinct responses and, in 'active-site' survivors, different switching mechanisms. At the active site, we find that promoter-adjacent breaks typically failed to trigger switching, 70 bp-repeat-adjacent breaks almost always triggered switching through 70 bp-repeat recombination (∼60% RAD51-dependent), and telomere-repeat-adjacent breaks triggered switching through loss of the VSG expression site (25% of survivors). Expression site loss was associated with G2/M-checkpoint bypass, while 70 bp-repeat-recombination was associated with DNA-resection, γH2A-focus assembly and a G2/M-checkpoint. Thus, the probability and mechanism of antigenic switching are highly dependent upon the location of the break. We conclude that 70 bp-repeat-adjacent and telomere-repeat-adjacent breaks trigger distinct checkpoint responses and VSG switching pathways. Our results show how subtelomere fragility can generate the triggers for the major antigenic variation mechanisms in the African

  6. Deforestation does not affect the prevalence of a common trypanosome in African birds.

    Science.gov (United States)

    Valkiūnas, Gediminas; Iezhova, Tatjana A; Sehgal, Ravinder N M

    2016-10-01

    In spite of numerous reports of avian Trypanosoma spp. in birds throughout the world, patterns of the distribution and prevalence of these blood parasites remains insufficiently understood. It is clear that spatial heterogeneity influences parameters of parasite distributions in natural populations, but data regarding avian trypanosomes are scarce. Using microscopy and molecular diagnostic methods, we analysed the variation of prevalence of avian Trypanosoma parasites in two widespread African bird species, the yellow-whiskered greenbul Andropadus latirostris and the olive sunbird Cyanomitra olivacea. In all, 353 birds were captured in pristine forests and agroforest sites in Cameroon and Ghana. Overall, the prevalence of avian trypanosomes was 51.3%. Five morphospecies were reported (Trypanosoma everetti, T. anguiformis, T. avium, T. naviformis, T. ontarioensis). Trypanosoma everetti predominated, representing 98% of all Trypanosoma spp. reports, and it was present in both avian hosts. The prevalence of T. everetti was significantly less in the yellow-whiskered greenbul (19%) than olive sunbird (83%), and the same pattern of prevalence was reported in these avian hosts at different study sites. We found no interaction between sites and the prevalence of T. everetti. For both avian hosts, the prevalence did not differ significantly between pristine forests and agroforests. This indicates the same pattern of transmission at sites with different levels of deforestation and suggests that spatial heterogeneity related to deforestation does not affect the prevalence of avian Trypanosoma infections. It is likely that host-related factors, but not environmental conditions favour or reduce these parasite infections in forests of sub-Saharan Africa. Microscopic and PCR-based diagnostics showed the same sensitivity in diagnostics of T. everetti. We discuss the implications of these findings for the epidemiology of avian trypanosomiasis in natural populations. Copyright

  7. Freshwater fish trypanosomes: definition of two types, host control by antibodies and lack of antigenic variation.

    Science.gov (United States)

    Overath, P; Haag, J; Mameza, M G; Lischke, A

    1999-12-01

    Haemoflagellates of the genus Trypanosoma are prevalent in freshwater fishes and are transmitted by leeches as vectors. As demonstrated by sequence comparisons of nuclear small subunit rRNA genes, trypanosomes isolated from several fish species at different localities can be divided into at least 2 closely related types, designated Type A and Type B. A clone derived from a Type A isolate from carp (Cyprinus carpio) was used to study the anti-parasite immune response in specified pathogen-free outbred carp. Infection leads to an initial rise in parasitaemia in the blood followed by a sharp decline in all fish (acute phase). Thereafter, in some carp, parasites become undetectable both in the blood and in internal organs while, in others, low numbers can be found in the blood for up to 1 year (chronic phase). Fish that have controlled an acute infection with the clone are not only protected against an homologous challenge infection, but also against the infection with parasite lines derived from carp in the chronic phase of infection. Passive immunization experiments with IgM purified from serum of recovered carp indicate that the infection is controlled by antibodies. The anti-parasite antibody level in recovered carp remains high for many months although the parasitaemia is controlled at very low levels and the half life of IgM, t1/2 = 22.5 days, is comparatively short. The effective control of trypanosomes in laboratory infections is in contrast to the high prevalence in natural and farmed freshwater fish populations.

  8. Geopolymer Mortar with Fly Ash

    Directory of Open Access Journals (Sweden)

    Saloma

    2016-01-01

    Full Text Available The cement industry accounts for about 7% of all CO2 emissions caused by humans. Therefore, it is necessary to find another material in order to support sustainable material. An alternative way is replacing cement material with alternative material as fly ash. Fly ash as binder need to be added alkaline activator in the form of sodium silicate (Na2SiO3 or potassium silicate (K2SiO3 and sodium hydroxide (NaOH or potassium hydroxide (KOH. The purpose of this research is to analyze the effect of activator liquid concentration on geopolymer mortar properties and to know the value of compressive strength. Molarity variation of NaOH are 8, 12, 14, and 16 M with ratio of Na2SiO3/NaOH = 1.0. Ratio of sand/fly ash = 2.75 and ratio of activator/fly ash = 0.8. The cube-shaped specimen 50 × 50 × 50 mm is cured by steam curing with a temperature of 60°C for 48 hours. The experimental result of fresh mortar reported that the molarity of NaOH affect the slump flow and setting time, higher of NaOH produces the smaller value of slump and the faster time of setting. The experimental of density results reported that the increase of specific gravity when the molarity of NaOH increased. The experimental results of the compressive strength are showed that the maximum compressive strength of geopolymer mortar 14 M is 10.06 MPa and the lowest compressive strength produced by geopolymer mortar 8 M is 3.95 MPa. Testing the compressive strength of geopolymer mortar 16 M produces compressive strength lower than 14 M geopolymer mortar is 9.16 MPa.

  9. Flying and Your Child's Ears

    Science.gov (United States)

    ... Media Flying and Your Child's Ears KidsHealth > For Parents > Flying and Your Child's Ears Print A A A What's in this article? Flying's Effects on Ears Tips for Easing Ear Pain en español Como cuidar los oídos de su hijo(a) cuando vuele en avión Flying's Effects on ...

  10. Flying in North America

    Directory of Open Access Journals (Sweden)

    Jaromír Procházka

    2013-01-01

    Full Text Available Flying all over the world is very challenging and demanding. Although ICAO is covering every specific detail by rules, there are some personal experiences which cannot be substituted. Some of them are point out in the article.

  11. Acetylcholinesterase mutations and organophosphate resistance in sand flies and mosquitoes

    Science.gov (United States)

    The sand fly, Phlebotomus papatasi (Scopoli) is a major vector of Leishamnia major, the principle causative agent of human cutaneous leishmaniasis in the Middle East, southern Europe, northern Africa, and Southern Asia. Sand fly bites and leishmaniasis significantly impacted U.S. military operations...

  12. The Fly Printer - Extended

    DEFF Research Database (Denmark)

    Beloff, Laura; Klaus, Malena

    2016-01-01

    Artist talk / Work-in-progress What is the purpose of a machine or an artifact, like the Fly Printer, that is dislocated, that produces images that have no meaning, no instrumentality, that depict nothing in the world? The biological and the cultural are reunited in this apparatus as a possibilit...... the results. The extended version of the Fly Printer containing the technological perception and DNNs is a collaboration between Laura Beloff and Malene Theres Klaus...

  13. An essential nuclear protein in trypanosomes is a component of mRNA transcription/export pathway.

    Directory of Open Access Journals (Sweden)

    Mariana Serpeloni

    Full Text Available In eukaryotic cells, different RNA species are exported from the nucleus via specialized pathways. The mRNA export machinery is highly integrated with mRNA processing, and includes a different set of nuclear transport adaptors as well as other mRNA binding proteins, RNA helicases, and NPC-associated proteins. The protozoan parasite Trypanosoma cruzi is the causative agent of Chagas disease, a widespread and neglected human disease which is endemic to Latin America. Gene expression in Trypanosoma has unique characteristics, such as constitutive polycistronic transcription of protein-encoding genes and mRNA processing by trans-splicing. In general, post-transcriptional events are the major points for regulation of gene expression in these parasites. However, the export pathway of mRNA from the nucleus is poorly understood. The present study investigated the function of TcSub2, which is a highly conserved protein ortholog to Sub2/ UAP56, a component of the Transcription/Export (TREX multiprotein complex connecting transcription with mRNA export in yeast/human. Similar to its orthologs, TcSub2 is a nuclear protein, localized in dispersed foci all over the nuclei -except the fibrillar center of nucleolus- and at the interface between dense and non-dense chromatin areas, proposing the association of TcSub2 with transcription/processing sites. These findings were analyzed further by BrUTP incorporation assays and confirmed that TcSub2 is physically associated with active RNA polymerase II (RNA pol II, but not RNA polymerase I (RNA pol I or Spliced Leader (SL transcription, demonstrating participation particularly in nuclear mRNA metabolism in T. cruzi. The double knockout of the TcSub2 gene is lethal in T. cruzi, suggesting it has an essential function. Alternatively, RNA interference assays were performed in Trypanosoma brucei. It allowed demonstrating that besides being an essential protein, its knockdown causes mRNA accumulation in the nucleus and

  14. The blow fly, Chrysomya megacephala, and the house fly, Musca domestica, as mechanical vectors of pathogenic bacteria in Northeast Thailand.

    Science.gov (United States)

    Chaiwong, T; Srivoramas, T; Sueabsamran, P; Sukontason, K; Sanford, M R; Sukontason, K L

    2014-06-01

    The Oriental latrine fly, Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) and the house fly, Musca domestica L., (Diptera: Muscidae) are synanthropic flies which are adapted to live in close association with human habitations, thereby making them likely mechanical vectors of several pathogens to humans. There were two main aims of this study. The first aim was to determine the prevalence of these two fly species from five types of human habitations including: fresh-food markets, garbage piles, restaurants, school cafeterias and paddy fields, in the Muang Ubon Ratchathani and Warinchamrap districts of Ubon Ratchathani province of Northeast Thailand. Flies collection were conducted monthly from September 2010-October 2011 using a reconstructable funnel trap, containing 1 day-tainted beef offal as bait. A total of 7 750 flies (6 401 C. megacephala and 1 349 M.domestica) were collected. The second aim was to examine the potential of these flies to carry pathogenic bacteria. Bacteria were isolated from 994 individual flies collected using a sweep net (555 C. megacephala and 439 M. domestica). A total of 15 bacterial genera were isolated from the external surfaces, comprising ten genera of gram-negative bacteria and five gram-positive bacteria. The most common bacteria isolated from both species were coagulase-negative staphylococci, followed by Streptococcus group D non-enterococci. Human pathogenic enteric bacteria isolated were Salmonella sp., Shigella sp., Escherichia coli O157:H7, Salmonella typhi, Bacillus sp., and Enterococcus sp., of which S. typhi is the first report of isolation from these fly species. Other human pathogens included Staphylococcus aureus and Pseudomonas aeruginosa. Not only were the number of C. megacephala positive for bacteria significantly higher than for M. domestica, but they were also carrying ~11-12 times greater bacterial load than M. domestica. These data suggest that both fly species should be considered potential

  15. SAND FLY SPECIES COMPOSITION (DIPTERA: PSYCHODIDAE: PHLEBOTOMINAE IN THE MUNICIPALITY OF CANTAGALO , AN AREA WITH SPORADIC CASES OF HUMAN CUTANEOUS LEISHMANIASIS IN RIO DE JANEIRO STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    Quezia Nunes PERES-DIAS

    2016-01-01

    Full Text Available SUMMARY The municipality of Cantagalo is an area with sustained transmission of American Cutaneous Leishmaniasis (ACL. Monthly sand fly collections were performed for three years (June 2012 - May 2015 using a CDC light trap. A total of 3,310 specimens belonging to 12 species were trapped: Nyssomyia intermedia, Nyssomyia whitmani, Migonemyia migonei, Evandromyia lenti, Evandromyia cortelezzii, Micropygomyia quinquefer, Brumptomyia brumpti, Psathyromyia aragaoi, Micropygomyia schreiberi, Pintomyia fischeri, Sciopemyia sordellii, and Evandromyia edwardsi. The last seven species have not been previously recorded in this area. The highest abundance of species occurred between October and March. October was the month with the highest number of captured sand flies, one month before the peak in the summer rainfall. In October the highest number of Ny. intermedia, Ny. whitmani and Mg. migonei, were also collected, the three epidemiologically most important species. The high abundance of species with epidemiological importance for ACL transmission might explain the sporadic occurrence of the disease in the area.

  16. Phylogenetic analysis of Bolivian bat trypanosomes of the subgenus schizotrypanum based on cytochrome B sequence and minicircle analyses.

    Directory of Open Access Journals (Sweden)

    Lineth García

    Full Text Available The aim of this study was to establish the phylogenetic relationships of trypanosomes present in blood samples of Bolivian Carollia bats. Eighteen cloned stocks were isolated from 115 bats belonging to Carollia perspicillata (Phyllostomidae from three Amazonian areas of the Chapare Province of Bolivia and studied by xenodiagnosis using the vectors Rhodnius robustus and Triatoma infestans (Trypanosoma cruzi marenkellei or haemoculture (Trypanosoma dionisii. The PCR DNA amplified was analyzed by nucleotide sequences of maxicircles encoding cytochrome b and by means of the molecular size of hyper variable regions of minicircles. Ten samples were classified as Trypanosoma cruzi marinkellei and 8 samples as Trypanosoma dionisii. The two species have a different molecular size profile with respect to the amplified regions of minicircles and also with respect to Trypanosoma cruzi and Trypanosoma rangeli used for comparative purpose. We conclude the presence of two species of bat trypanosomes in these samples, which can clearly be identified by the methods used in this study. The presence of these trypanosomes in Amazonian bats is discussed.

  17. Composting poultry manure by fly larvae (Musca domestica) eliminates Campylobacter jejuni from the manure

    DEFF Research Database (Denmark)

    Nordentoft, Steen; Hald, Birthe

    2013-01-01

    Introduction The common house fly, Musca domestica (Md) is an important carrier of zoonotic agents, and Campylobacter jejuni is one that may be transmitted between animals and humans by flies. Colonized animals shed the bacteria in feces where larval stages of Md flies develops. Aim of the present...

  18. Global warming and house fly control: direct effects and biodiversity concerns.

    Science.gov (United States)

    House flies are major pests of human and animal health throughout the world and are among the most difficult to control. Effective fly management relies on a balance of sanitation, insecticide use, and biological control. Climate change could upset that balance in favor of the fly unless pro-activ...

  19. Drug-mediated inhibition of Fli-1 for the treatment of leukemia

    OpenAIRE

    Li, Y-J; Zhao, X.; Vecchiarelli-Federico, L M; Li, Y; Datti, A.; Cheng, Y.; Ben-David, Y

    2012-01-01

    The Ets transcription factor, Fli-1 is activated in murine erythroleukemia and overexpressed in various human malignancies including Ewing's sarcoma, induced by the oncogenic fusion protein EWS/Fli-1. Recent studies by our group and others have demonstrated that Fli-1 plays a key role in tumorigenesis, and disrupting its oncogenic function may serve as a potential treatment option for malignancies associated with its overexpression. Herein, we describe the discovery of 30 anti-Fli-1 compounds...

  20. Significance and survival of Enterococci during the house fly development.

    Science.gov (United States)

    Ghosh, Anuradha; Akhtar, Mastura; Holderman, Chris; Zurek, Ludek

    2014-01-01

    House flies are among the most important nonbiting insect pests of medical and veterinary importance. Larvae develop in decaying organic substrates and their survival strictly depends on an active microbial community. House flies have been implicated in the ecology and transmission of enterococci, including multi-antibiotic-resistant and virulent strains of Enterococcus faecalis. In this study, eight American Type Culture Collection type strains of enterococci including Enterococcus avium, Enterococcus casseliflavus, Enterococcus durans, Enterococcus hirae, Enterococcus mundtii, Enterococcus gallinarum, Enterococcusfaecalis, and Enterococcusfaecium were evaluated for their significance in the development of house flies from eggs to adults in bacterial feeding assays. Furthermore, the bacterial colonization of the gut of teneral flies as well as the importance of several virulence traits of E. faecalis in larval mortality was assessed. Overall survival of house flies (egg to adult) was significantly higher when grown with typically nonpathogenic enterococcal species such as E. hirae (76.0% survival), E. durans (64.0%), and E. avium (64.0%) compared with that with clinically important species E. faecalis (24.0%) and E. faecium (36.0%). However, no significant differences in survival of house fly larvae were detected when grown with E. faecalis strains carrying various virulence traits, including isogenic mutants of the human clinical isolate E. faecalis V583 with in-frame deletions of gelatinase, serine protease, and capsular polysaccharide serotype C. Enterococci were commonly detected in fly puparia (range: 75-100%; concentration: 103-105 CFU/puparium);however, the prevalence of enterococci in teneral flies varied greatly: from 25.0 (E. casseliflavus) to 89.5% (E. hirae). In conclusion, depending on the species, enterococci variably support house fly larval development and colonize the gut of teneral adults. The human pathogenic species, E. faecalis and E. faecium

  1. ANALYSIS OF FLYING BIKE

    OpenAIRE

    Momin Irfan Ali Nasir Husain *1, Shah mohd. Rafique rahmatullah *2, Naumanulhaq Barkatullah Shaikh *3, Khatib Mohd. Azimuddin Najimuddin *4, Ansari Mohammad Naasir Shamsudduha *5, Ansari Mohammad Parvez Abdul Qayyum*6, Momin Mohammad Rayyan Mohammad Shakeel*7, Ansari Peer Mohammed Munna *8, Prof. Mohd. Musharraf Aamir

    2016-01-01

    Flying Bike vertical take-off and landing (VTOL) type machine which also follows Newton’s third law. It is thought of as a conventional type of aircraft with special features added to enable it to rise vertically during take-off and to land from a vertical descent.  It flies with two propellers located at front and back side. These propellers are having hovering abilities. The vehicle is controlled by tilting the propellers by using lever mechanism. Rotation is carried out by diffe...

  2. Importance of Campylobacter jejuni FliS and FliW in Flagella Biogenesis and Flagellin Secretion

    Science.gov (United States)

    Radomska, Katarzyna A.; Wösten, Marc M. S. M.; Ordoñez, Soledad R.; Wagenaar, Jaap A.; van Putten, Jos P. M.

    2017-01-01

    Flagella-driven motility enables bacteria to reach their favorable niche within the host. The human foodborne pathogen Campylobacter jejuni produces two heavily glycosylated structural flagellins (FlaA and FlaB) that form the flagellar filament. It also encodes the non-structural FlaC flagellin which is secreted through the flagellum and has been implicated in host cell invasion. The mechanisms that regulate C. jejuni flagellin biogenesis and guide the proteins to the export apparatus are different from those in most other enteropathogens and are not fully understood. This work demonstrates the importance of the putative flagellar protein FliS in C. jejuni flagella assembly. A constructed fliS knockout strain was non-motile, displayed reduced levels of FlaA/B and FlaC flagellin, and carried severely truncated flagella. Pull-down and Far Western blot assays showed direct interaction of FliS with all three C. jejuni flagellins (FlaA, FlaB, and FlaC). This is in contrast to, the sensor and regulator of intracellular flagellin levels, FliW, which bound to FlaA and FlaB but not to FlaC. The FliS protein but not FliW preferred binding to glycosylated C. jejuni flagellins rather than to their non-glycosylated recombinant counterparts. Mapping of the binding region of FliS and FliW using a set of flagellin fragments showed that the C-terminal subdomain of the flagellin was required for FliS binding, whereas the N-terminal subdomain was essential for FliW binding. The separate binding subdomains required for FliS and FliW, the different substrate specificity, and the differential preference for binding of glycosylated flagellins ensure optimal processing and assembly of the C. jejuni flagellins. PMID:28659885

  3. Importance of Campylobacter jejuni FliS and FliW in Flagella Biogenesis and Flagellin Secretion

    Directory of Open Access Journals (Sweden)

    Katarzyna A. Radomska

    2017-06-01

    Full Text Available Flagella-driven motility enables bacteria to reach their favorable niche within the host. The human foodborne pathogen Campylobacter jejuni produces two heavily glycosylated structural flagellins (FlaA and FlaB that form the flagellar filament. It also encodes the non-structural FlaC flagellin which is secreted through the flagellum and has been implicated in host cell invasion. The mechanisms that regulate C. jejuni flagellin biogenesis and guide the proteins to the export apparatus are different from those in most other enteropathogens and are not fully understood. This work demonstrates the importance of the putative flagellar protein FliS in C. jejuni flagella assembly. A constructed fliS knockout strain was non-motile, displayed reduced levels of FlaA/B and FlaC flagellin, and carried severely truncated flagella. Pull-down and Far Western blot assays showed direct interaction of FliS with all three C. jejuni flagellins (FlaA, FlaB, and FlaC. This is in contrast to, the sensor and regulator of intracellular flagellin levels, FliW, which bound to FlaA and FlaB but not to FlaC. The FliS protein but not FliW preferred binding to glycosylated C. jejuni flagellins rather than to their non-glycosylated recombinant counterparts. Mapping of the binding region of FliS and FliW using a set of flagellin fragments showed that the C-terminal subdomain of the flagellin was required for FliS binding, whereas the N-terminal subdomain was essential for FliW binding. The separate binding subdomains required for FliS and FliW, the different substrate specificity, and the differential preference for binding of glycosylated flagellins ensure optimal processing and assembly of the C. jejuni flagellins.

  4. Filth fly transmission of Escherichia coli O157:H7 and Salmonella enterica to lettuce, Lactuca sativa

    Science.gov (United States)

    Filth flies have been implicated in the dispersal of human disease pathogens; however, fly transmission parameters of human pathogens to plants are largely undescribed. The capacity of the black blow fly, Phormia regina, to acquire and subsequently release bacteria onto baby lettuce leaves was comp...

  5. Biodiversity, Anti-Trypanosomal Activity Screening, and Metabolomic Profiling of Actinomycetes Isolated from Mediterranean Sponges.

    Directory of Open Access Journals (Sweden)

    Cheng Cheng

    Full Text Available Marine sponge-associated actinomycetes are considered as promising sources for the discovery of novel biologically active compounds. In the present study, a total of 64 actinomycetes were isolated from 12 different marine sponge species that had been collected offshore the islands of Milos and Crete, Greece, eastern Mediterranean. The isolates were affiliated to 23 genera representing 8 different suborders based on nearly full length 16S rRNA gene sequencing. Four putatively novel species belonging to genera Geodermatophilus, Microlunatus, Rhodococcus and Actinomycetospora were identified based on a 16S rRNA gene sequence similarity of < 98.5% to currently described strains. Eight actinomycete isolates showed bioactivities against Trypanosma brucei brucei TC221 with half maximal inhibitory concentration (IC50 values <20 μg/mL. Thirty four isolates from the Milos collection and 12 isolates from the Crete collection were subjected to metabolomic analysis using high resolution LC-MS and NMR for dereplication purposes. Two isolates belonging to the genera Streptomyces (SBT348 and Micromonospora (SBT687 were prioritized based on their distinct chemistry profiles as well as their anti-trypanosomal activities. These findings demonstrated the feasibility and efficacy of utilizing metabolomics tools to prioritize chemically unique strains from microorganism collections and further highlight sponges as rich source for novel and bioactive actinomycetes.

  6. Uptake of NO-releasing drugs by the P2 nucleoside transporter in trypanosomes

    Directory of Open Access Journals (Sweden)

    L. Soulère

    1999-11-01

    Full Text Available Nitric oxide (NO· has been identified as a principal regulatory molecule of the immune system and the major cytotoxic mediator of activated immune cells. NO· can also react rapidly with a variety of biological species, particularly with the superoxide radical anion O2·- at almost diffusion-limited rates to form peroxynitrite anion (ONOO-. ONOO- and its proton-catalyzed decomposition products are capable of oxidizing a great diversity of biomolecules and can act as a source of toxic hydroxyl radicals. As a consequence, a strategy for the development of molecules with potential trypanocidal activities could be developed to increase the concentration of nitric oxide in the parasites through NO·-releasing compounds. In this way, the rate of formation of peroxynitrite from NO· and O2·- would be faster than the rate of dismutation of superoxide radicals by superoxide dismutases which constitute the primary antioxidant enzymatic defense system in trypanosomes. The adenosine transport systems of parasitic protozoa, which are also in certain cases implicated in the selective uptake of active drugs such as melarsoprol or pentamidine, could be exploited to specifically target these NO·-releasing compounds inside the parasites. In this work, we present the synthesis, characterization and biological evaluation of a series of molecules that contain both a group which would specifically target these drugs inside the parasites via the purine transporter, and an NO·-donor group that would exert a specific pharmacological effect by increasing NO level, and thus the peroxynitrite concentration inside the parasite.

  7. Morphological Features of Trypanosomes from Squirrel Monkeys from the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Mariangela Ziccardi

    1998-01-01

    Full Text Available A morphometric analysis of blood trypomastigotes identified as Trypanosoma minasense, T. saimirii, and T. rangeli harbored by squirrel monkeys from the Brazilian Amazon was performed. Additionally, morphological and biological comparative analyses were conducted of T. saimirii-like and T. rangeli development forms from haemoculture and xenodiagnosis. Illustrations are given of blood trypomastigotes as well as of developing flagellates in triatomine and axenic culture. Mean values of blood trypomastigotes of T. saimirii differ statistically from those of T. rangeli in only two out of ten morphological characters measured, and ranges overlapped. The developing forms of T. saimrii-like parasites were essentially identical in both xenodiagnosis and haemoculture to those of T. rangeli. Trypanosomes confirmed as T. rangeli were transmitted to mice by the bites of the great majority of triatomines that fed on T. saimirii-like infected monkeys. We conclude that, based on morphology and on the development in triatomine bugs and haemoculture, T. saimirii should not be considered a distinct species. We therefore propose T. saimirii to be a junior synonym of T. rangeli

  8. TAC102 Is a Novel Component of the Mitochondrial Genome Segregation Machinery in Trypanosomes.

    Directory of Open Access Journals (Sweden)

    Roman Trikin

    2016-05-01

    Full Text Available Trypanosomes show an intriguing organization of their mitochondrial DNA into a catenated network, the kinetoplast DNA (kDNA. While more than 30 proteins involved in kDNA replication have been described, only few components of kDNA segregation machinery are currently known. Electron microscopy studies identified a high-order structure, the tripartite attachment complex (TAC, linking the basal body of the flagellum via the mitochondrial membranes to the kDNA. Here we describe TAC102, a novel core component of the TAC, which is essential for proper kDNA segregation during cell division. Loss of TAC102 leads to mitochondrial genome missegregation but has no impact on proper organelle biogenesis and segregation. The protein is present throughout the cell cycle and is assembled into the newly developing TAC only after the pro-basal body has matured indicating a hierarchy in the assembly process. Furthermore, we provide evidence that the TAC is replicated de novo rather than using a semi-conservative mechanism. Lastly, we demonstrate that TAC102 lacks an N-terminal mitochondrial targeting sequence and requires sequences in the C-terminal part of the protein for its proper localization.

  9. Purification of the spliced leader ribonucleoprotein particle from Leptomonas collosoma revealed the existence of an Sm protein in trypanosomes. Cloning the SmE homologue.

    Science.gov (United States)

    Goncharov, I; Palfi, Z; Bindereif, A; Michaeli, S

    1999-04-30

    Trans-splicing in trypanosomes involves the addition of a common spliced leader (SL) sequence, which is derived from a small RNA, the SL RNA, to all mRNA precursors. The SL RNA is present in the cell in the form of a ribonucleoprotein, the SL RNP. Using conventional chromatography and affinity selection with 2'-O-methylated RNA oligonucleotides at high ionic strength, five proteins of 70, 16, 13, 12, and 8 kDa were co-selected with the SL RNA from Leptomonas collosoma, representing the SL RNP core particle. Under conditions of lower ionic strength, additional proteins of 28 and 20 kDa were revealed. On the basis of peptide sequences, the gene coding for a protein with a predicted molecular weight of 11.9 kDa was cloned and identified as homologue of the cis-spliceosomal SmE. The protein carries the Sm motifs 1 and 2 characteristic of Sm antigens that bind to all known cis-spliceosomal uridylic acid-rich small nuclear RNAs (U snRNAs), suggesting the existence of Sm proteins in trypanosomes. This finding is of special interest because trypanosome snRNPs are the only snRNPs examined to date that are not recognized by anti-Sm antibodies. Because of the early divergence of trypanosomes from the eukaryotic lineage, the trypanosome SmE protein represents one of the primordial Sm proteins in nature.

  10. Kite-Flying Fun

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    China’s kite capital welcomes flying enthusiasts from across the world to its annual carnival Tens of thousands of kite enthusiast from all over the world gathered under the growing swarm of brightly colored kites. Some of the floating and billowing forms had been fashioned into

  11. Dose-dependent fate of GFP-E. coli in the alimentary canal of adult house flies

    Science.gov (United States)

    Adult house flies (Diptera: Muscidae; Musca domestica L.) disseminate bacteria from microbe-rich substrates to areas where humans and domesticated animals reside. Because bacterial abundance fluctuates widely across substrates, flies encounter and ingest varying amounts of bacteria. We investigated ...

  12. Hydration of fly ash cement

    Energy Technology Data Exchange (ETDEWEB)

    Etsuo Sakai; Shigeyoshi Miyahara; Shigenari Ohsawa; Seung-Heun Lee; Masaki Daimon [Tokyo Institute of Technology, Tokyo (Japan). Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering

    2005-06-01

    It is necessary to establish the material design system for the utilization of large amounts of fly ash as blended cement instead of disposing of it as a waste. Cement blended with fly ash is also required as a countermeasure to reduce the amount of CO{sub 2} generation. In this study, the influences of the glass content and the basicity of glass phase on the hydration of fly ash cement were clarified and hydration over a long curing time was characterized. Two kinds of fly ash with different glass content, one with 38.2% and another with 76.6%, were used. The hydration ratio of fly ash was increased by increasing the glass content in fly ash in the specimens cured for 270 days. When the glass content of fly ash is low, the basicity of glass phase tends to decrease. Reactivity of fly ash is controlled by the basicity of the glass phase in fly ash during a period from 28 to 270 days. However, at an age of 360 days, the reaction ratios of fly ash show almost identical values with different glass contents. Fly ash also affected the hydration of cement clinker minerals in fly ash cement. While the hydration of alite was accelerated, that of belite was retarded at a late stage.

  13. The hormonal and behavioral response to the presence and activities of humans in three co-roosting flying fox species (Acerodon jubatus, Pteropus vampyrus and P. hypomelanus) in Boracay and Mambukal in the Philippines

    NARCIS (Netherlands)

    van der Aa, Pascal J.H.; Lorica, Renee P.; Komdeur, Jan

    2006-01-01

    Many species of large flying foxes are endangered, mainly due to habitat loss and hunting. Although hunting and logging are prohibited in many areas in the Old World Tropics, numbers of flying foxes are still decreasing. The best compromise for the welfare of both local residents and flying foxes in

  14. Diet modification and metformin have a beneficial effect in a fly model of obesity and mucormycosis.

    Science.gov (United States)

    Shirazi, Fazal; Farmakiotis, Dimitrios; Yan, Yuanqing; Albert, Nathaniel; Do, Kim-Anh; Kim-Anh, Do; Kontoyiannis, Dimitrios P

    2014-01-01

    In an experimental model of obesity and hyperglycemia in Drosophila melanogaster we studied the effect of diet modification and administration of metformin on systemic infection with Rhizopus, a common cause of mucormycosis in diabetic patients. Female Wt-type Drosophila flies were fed regular (RF) or high-fat diet (HFD; 30% coconut oil) food with or without metformin for 48 h and then injected with R. oryzae. Survival rates, glucose and triglyceride levels were compared between 1) normal-weight flies (RF), 2) obese flies (HFD), 3) obese flies fed with RF, 4) flies continuously fed on HFD + metformin, 5) flies fed on HFD + metformin, then transferred to RF, and 6) obese flies administered metformin after infection [corrected].Glucose levels were compared across groups of non-infected flies and across groups of infected flies. Survival was significantly decreased (P = 0.003) in obese flies, while post-infection glucose levels were significantly increased (P = 0.0001), compared to normal-weight flies. Diet and administration of metformin led to weight loss, normalized glucose levels during infection, and were associated with decreased mortality and tissue fungal burden. In conclusion, diet and metformin help control infection-associated hyperglycemia and improve survival in Drosophila flies with mucormycosis. Fly models of obesity bear intriguing similarities to the pathophysiology of insulin resistance and diabetes in humans, and can provide new insights into the pathogenesis and treatment of infections in obese and diabetic patients.

  15. Diet modification and metformin have a beneficial effect in a fly model of obesity and mucormycosis.

    Directory of Open Access Journals (Sweden)

    Fazal Shirazi

    Full Text Available In an experimental model of obesity and hyperglycemia in Drosophila melanogaster we studied the effect of diet modification and administration of metformin on systemic infection with Rhizopus, a common cause of mucormycosis in diabetic patients. Female Wt-type Drosophila flies were fed regular (RF or high-fat diet (HFD; 30% coconut oil food with or without metformin for 48 h and then injected with R. oryzae. Survival rates, glucose and triglyceride levels were compared between 1 normal-weight flies (RF, 2 obese flies (HFD, 3 obese flies fed with RF, 4 flies continuously fed on HFD + metformin, 5 flies fed on HFD + metformin, then transferred to RF, and 6 obese flies administered metformin after infection [corrected].Glucose levels were compared across groups of non-infected flies and across groups of infected flies. Survival was significantly decreased (P = 0.003 in obese flies, while post-infection glucose levels were significantly increased (P = 0.0001, compared to normal-weight flies. Diet and administration of metformin led to weight loss, normalized glucose levels during infection, and were associated with decreased mortality and tissue fungal burden. In conclusion, diet and metformin help control infection-associated hyperglycemia and improve survival in Drosophila flies with mucormycosis. Fly models of obesity bear intriguing similarities to the pathophysiology of insulin resistance and diabetes in humans, and can provide new insights into the pathogenesis and treatment of infections in obese and diabetic patients.

  16. Improving the cost-effectiveness of visual devices for the control of riverine tsetse flies, the major vectors of human African trypanosomiasis.

    Directory of Open Access Journals (Sweden)

    Johan Esterhuizen

    2011-08-01

    Full Text Available Control of the Riverine (Palpalis group of tsetse flies is normally achieved with stationary artificial devices such as traps or insecticide-treated targets. The efficiency of biconical traps (the standard control device, 1×1 m black targets and small 25×25 cm targets with flanking nets was compared using electrocuting sampling methods. The work was done on Glossina tachinoides and G. palpalis gambiensis (Burkina Faso, G. fuscipes quanzensis (Democratic Republic of Congo, G. f. martinii (Tanzania and G. f. fuscipes (Kenya. The killing effectiveness (measured as the catch per m(2 of cloth for small targets plus flanking nets is 5.5-15X greater than for 1 m(2 targets and 8.6-37.5X greater than for biconical traps. This has important implications for the costs of control of the Riverine group of tsetse vectors of sleeping sickness.

  17. Resolving the question of trypanosome monophyly: a comparative genomics approach using whole genome data sets with low taxon sampling.

    Science.gov (United States)

    Leonard, Guy; Soanes, Darren M; Stevens, Jamie R

    2011-07-01

    Since the first attempts to classify the evolutionary history of trypanosomes, there have been conflicting reports regarding their true phylogenetic relationships and, in particular, their relationships with other vertebrate trypanosomatids, e.g. Leishmania sp., as well as with the many insect parasitising trypanosomatids. Perhaps the issue that has provided most debate is that concerning the monophyly (or otherwise) of genus Trypanosoma and, even with the advent of molecular methods, the findings of numerous studies have varied significantly depending on the gene sequences analysed, number of taxa included, choice of outgroup and phylogenetic methodology. While of arguably limited applied importance, resolution of the question as to whether or not trypanosomes are monophyletic is critical to accurate evaluation of competing, mutually exclusive evolutionary scenarios for these parasites, namely the 'vertebrate-first' or 'insect-first' hypotheses. Therefore, a new approach, which could overcome previous limitations was needed. At its most simple, the problem can be defined within the framework of a trifurcated tree with three hypothetical positions at which the root can be placed. Using BLASTp and whole-genome gene-by-gene phylogenetic analyses of Trypanosoma brucei, Trypanosoma cruzi, Leishmania major and Naegleria gruberi, we have identified 599 gene markers--putative homologues--that were shared between the genomes of these four taxa. Of these, 75 homologous gene families that demonstrate monophyly of the kinetoplastids were identified. We then used these data sets in combination with an additional outgroup, Euglena gracilis, coupled with large-scale gene concatenation and diverse phylogenetic techniques to investigate the relative branching order of T. brucei, T. cruzi and L. major. Our findings confirm the monophyly of genus Trypanosoma and demonstrate that <1% of the analysed gene markers shared between the genomes of T. brucei, T. cruzi and L. major reject

  18. Growth and differentiation on a trypanosome of the subgenus Schizotrypanum from the bat Phyllostomus hastatus

    Directory of Open Access Journals (Sweden)

    Sônia I. Hamanaka

    1993-12-01

    Full Text Available The effects of temperature, pH, osmolarity and aeration on the growth and differentiation of a trypanosome ofthe subgenus Schizotrypanum isolatedfrom the bat Phyllostomus hastatus were studied. In general, the growth characteristics ofthe flagellate were similar to those of Trypanosoma (Schizotrypanum cruzi. However, the parasite did not growth at 33 or 37C. Increase in the osmolarity and aeration promoted growth at 33C. Significant metacyclogenesis was detected only in the growth condition where maximal growth occured (28C, pH 7.3, 380m0s/kg, in tissue cullure flasks, at the end ofthe exponential growth phase. The begining of the metacyclogenesis process was coincident with most glucose utilization and lowest pH. During metacyclogenesis both culture medium pH and osmolarity increased steadly.Foram estudados os efeitos da temperatura, do pH, da osmolaridade e da areaçâo sobre o crescimento e a diferenciação de um tripanosoma do subgenêro Schizotrypanum, isolado do morcego Phyllostomus hastatus. Em geral, as características do crescimento do flagelado foram semelhantes àquelas do Trypanosoma (Schizotrypanum cruzi. Entretanto, o parasita não de desenvolveu a 33 ou 37°C. O aumento na osmolaridade e areaçâo estimulou o crescimento a 33°C. Metaciclogênese sifhificativa foi detectada somente na condição de crescimento, onde ocorreu desenvolvimento máximo (28°C, pH 7.3, 320m0/kg H20, em frascos de cultura de tecido, no final da fase do crescimento exponencial. O início do processo de metaciclogênese coincidiu com maior utilização de glucose e menor pH. Durante a metaciclogênese, o pHdo meio de cultura e a osmolaridade aumentaram constantemente.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Defining the RNA-Protein Interactions in the Trypanosome Preribosomal Complex

    Science.gov (United States)

    Wang, Lei; Ciganda, Martin

    2013-01-01

    In eukaryotes, 5S rRNA is transcribed in the nucleoplasm and requires the ribosomal protein L5 to deliver it to the nucleolus for ribosomal assembly. The trypanosome-specific proteins P34 and P37 form a novel preribosomal complex with the eukaryotic conserved L5-5S rRNA complex in the nucleoplasm. Previous results suggested that P34 acts together with L5 to bridge the interaction with 5S rRNA and thus to stabilize 5S rRNA, an important role in the early steps of ribosomal biogenesis. Here, we have delineated the domains of the two protein components, L5 and P34, and regions of the RNA partner, 5S rRNA, that are critical for protein-RNA interactions within the complex. We found that the L18 domain of L5 and the N terminus and RNA recognition motif of P34 bind 5S rRNA. We showed that Trypanosoma brucei L5 binds the β arm of 5S rRNA, while P34 binds loop A/stem V of 5S rRNA. We demonstrated that 5S rRNA is able to enhance the association between the protein components of the complex, L5 and P34. Both loop A/stem V and the β arm of 5S rRNA can separately enhance the protein-protein association, but their effects are neither additive nor synergistic. Domains in the two proteins for protein-protein and protein-RNA interactions overlap or are close to each other. This suggests that 5S rRNA binding might cause conformational changes in L5 and P34 and might also bridge the interactions, thus enhancing binding between the protein partners of this novel complex. PMID:23397568

  1. Regulated expression of an essential allosteric activator of polyamine biosynthesis in African trypanosomes.

    Directory of Open Access Journals (Sweden)

    Erin K Willert

    2008-10-01

    Full Text Available Trypanosoma brucei is the causative agent of African sleeping sickness. The polyamine biosynthetic pathway has the distinction of being the target of the only clinically proven anti-trypanosomal drug with a known mechanism of action. Polyamines are essential for cell growth, and their metabolism is extensively regulated. However, trypanosomatids appear to lack the regulatory control mechanisms described in other eukaryotic cells. In T. brucei, S-adenosylmethionine decarboxylase (AdoMetDC and ornithine decarboxylase (ODC are required for the synthesis of polyamines and also for the unique redox-cofactor trypanothione. Further, trypanosomatid AdoMetDC is activated by heterodimer formation with a catalytically dead homolog termed prozyme, found only in these species. To study polyamine regulation in T. brucei, we generated inducible AdoMetDC RNAi and prozyme conditional knockouts in the mammalian blood form stage. Depletion of either protein led to a reduction in spermidine and trypanothione and to parasite death, demonstrating that prozyme activation of AdoMetDC is essential. Under typical growth conditions, prozyme concentration is limiting in comparison to AdoMetDC. However, both prozyme and ODC protein levels were significantly increased relative to stable transcript levels by knockdown of AdoMetDC or its chemical inhibition. Changes in protein stability do not appear to account for the increased steady-state protein levels, as both enzymes are stable in the presence of cycloheximide. These observations suggest that prozyme and ODC are translationally regulated in response to perturbations in the pathway. In conclusion, we describe the first evidence for regulation of polyamine biosynthesis in T. brucei and we demonstrate that the unique regulatory subunit of AdoMetDC is a key component of this regulation. The data support ODC and AdoMetDC as the key control points in the pathway and the likely rate-limiting steps in polyamine biosynthesis.

  2. The effective eradication and control strategies for tsetse and ...

    African Journals Online (AJOL)

    Trypanosomiasis is a zoonotic disease transmitted mainly by tsetse flies, ... Trypanosomes are protozoan blood parasites that cause animal and human ... Parasite control which involves chemotherapy (use of trypanocidal drugs) to kill the ...

  3. Flying Saucer? Aliens?

    Science.gov (United States)

    1961-01-01

    No, it's not a flying saucer, it is the domed top to a 70 foot long vacuum tank at the Lewis Research Center's Electric Propulsion Laboratory, Cleveland, Ohio. The three technicians shown here in protective clothing had just emerged from within the tank where they had been cleaning in the toxic mercury atmosphere, left after ion engine testing in the tank. Lewis has since been renamed the John H. Glenn Research Center.

  4. Choice of optimal biocide combination to control flies (Diptera: Muscidae)

    OpenAIRE

    Mihaela Kavran; Marija F Zgomba; Aleksandra M Ignjatovic-Ćupina; Sanja D Lazić; Dušan V Petrić

    2015-01-01

    Introduction. Flies – by feeding on decaying matter, human waste and food – have been implicated in the spread of numerous animal and human diseases. Excessive fly populations are generally associated with livestock units and domestic waste due to decaying organic matter. A large number of flies cause extreme disturbance in the behavior of the host, resulting in skin irritation, lesions, wounds, and secondary infections are likely to appear. Objective. The aim of this study was to evalu...

  5. Feeding preferences of Lutzomyia longipalpis (Diptera: Psychodidae), the sand fly vector, for Leishmania infantum (Kinetoplastida: Trypanosomatidae).

    Science.gov (United States)

    Macedo-Silva, Virgínia P; Martins, Daniella R A; De Queiroz, Paula Vivianne Souza; Pinheiro, Marcos Paulo G; Freire, Caio C M; Queiroz, José W; Dupnik, Kathryn M; Pearson, Richard D; Wilson, Mary E; Jeronimo, Selma M B; Ximenes, Maria De Fátima F M

    2014-01-01

    Leishmania infantum, the causative agent of visceral leishmaniasis (VL) in Brazil, is spread mostly by the bite of the sand fly Lutzomyia longipalpis (Lutz & Neiva). We trapped sand flies in endemic neighborhoods near Natal, Brazil, where cases of human and dog VL were documented. Amplification of species-specific cytochrome b (Cyt b) genes by polymerase chain reaction revealed that sand flies from rural and periurban areas harbored blood from different sources. The most common source ofbloodmeal was human, but blood from dog, chicken, and armadillo was also present. We tested the preference for a source of bloodmeal experimentally by feeding L. longipalpis F1 with blood from different animals. There were significant differences between the proportion of flies engorged and number of eggs laid among flies fed on different sources, varying from 8.4 to 19 (P sand fly oviposition, but human blood also supported sand fly oviposition well. No sand flies fed on cats, and sand flies feeding on the opossum Monodelphis domestica Wagner produced no eggs. These data support the hypothesis that L. longipalpis is an eclectic feeder, and humans are an important source of blood for this sand fly species in periurban areas of Brazil.

  6. Pentamidine movement across the murine blood-brain and blood-cerebrospinal fluid barriers: effect of trypanosome infection, combination therapy, P-glycoprotein, and multidrug resistance-associated protein.

    Science.gov (United States)

    Sanderson, Lisa; Dogruel, Murat; Rodgers, Jean; De Koning, Harry Pieter; Thomas, Sarah Ann

    2009-06-01

    During the first stage of human African trypanosomiasis (HAT), Trypanosoma brucei gambiense is found mainly in the blood, and pentamidine treatment is used. Pentamidine is predominantly ineffective once the parasites have invaded the central nervous system (CNS). This lack of efficacy is thought to be due to the inability of pentamidine to cross the blood-brain barrier, although this has never been explored directly. This study addresses this using brain perfusion in healthy mice, P-glycoprotein-deficient mice, and in a murine model of HAT (T. brucei brucei). The influence of additional antitrypanosomal drugs on pentamidine delivery to the CNS also was investigated. Results revealed that [(3)H]pentamidine can cross the blood-brain barrier, although a proportion was retained by the capillary endothelium and failed to reach the healthy or trypanosome-infected brain (up to day 21 p.i.). The CNS distribution of pentamidine was increased in the final (possibly terminal) stage of trypanosome infection, partly because of loss of barrier integrity (days 28-35 p.i.) as measured by [(14)C]sucrose and [(3)H]suramin. Furthermore, pentamidine distribution to the CNS involved influx and efflux [via P-glycoprotein and multidrug resistance-associated protein (MRP)] transporters and was affected by the other antitrypanosomal agents, suramin, melarsoprol, and nifurtimox, but not eflornithine. These interactions could contribute to side effects or lead to the development of parasite resistance to the drugs. Thus, great care must be taken when designing drug combinations containing pentamidine or other diamidine analogs. However, coadministration of P-glycoprotein and/or MRP inhibitors with pentamidine or other diamidines might provide a means of improving efficacy against CNS stage HAT.

  7. A haptoglobin-hemoglobin receptor conveys innate immunity to Trypanosoma brucei in humans

    DEFF Research Database (Denmark)

    Vanhollebeke, Benoit; De Muylder, Géraldine; Nielsen, Marianne J

    2008-01-01

    binds the haptoglobin-hemoglobin complex with high affinity for the uptake and incorporation of heme into intracellular hemoproteins. In mice, this receptor was required for optimal parasite growth and the resistance of parasites to the oxidative burst by host macrophages. In humans, the trypanosome...... receptor also recognized the complex between hemoglobin and haptoglobin-related protein, which explains its ability to capture trypanolytic HDLs. Thus, in humans the presence of haptoglobin-related protein has diverted the function of the trypanosome haptoglobin-hemoglobin receptor to elicit innate host...

  8. Evil in Lord of the Flies

    Institute of Scientific and Technical Information of China (English)

    黄靓

    2008-01-01

    Lord of the Flies deals with the problem of the nature of human personality and the reflection of personality on society.Devils hidesomewhere dee in side of all people.Without morals,law and order it will eventually surface and come out.Evil it;the natural product of their con-sciousness.Simon understands,and this is the wisdom Golding treats with awe.that evil is"only us".

  9. Flying the Needles: Flight Deck Automation Erodes Fine-Motor Flying Skills Among Airline Pilots.

    Science.gov (United States)

    Haslbeck, Andreas; Hoermann, Hans-Juergen

    2016-06-01

    The aim of this study was to evaluate the influence of practice and training on fine-motor flying skills during a manual instrument landing system (ILS) approach. There is an ongoing debate that manual flying skills of long-haul crews suffer from a lack of flight practice due to conducting only a few flights per month and the intensive use of automation. However, objective evidence is rare. One hundred twenty-six randomly selected airline pilots had to perform a manual flight scenario with a raw data precision approach. Pilots were assigned to four equal groups according to their level of practice and training by fleet (short-haul, long-haul) and rank (first officer, captain). Average ILS deviation scores differed significantly in relation to the group assignments. The strongest predictor variable was fleet, indicating degraded performance among long-haul pilots. Manual flying skills are subject to erosion due to a lack of practice on long-haul fleets: All results support the conclusion that recent flight practice is a significantly stronger predictor for fine-motor flying performance than the time period since flight school or even the total or type-specific flight experience. Long-haul crews have to be supported in a timely manner by adequate training tailored to address manual skills or by operational provisions like mixed-fleet flying or more frequent transitions between short-haul and long-haul operation. © 2016, Human Factors and Ergonomics Society.

  10. FLI1 polymorphism affects susceptibility to cutaneous leishmaniasis in Brazil

    OpenAIRE

    Castellucci, L; Jamieson, SE; Miller, EN; de Almeida, LF; J. Oliveira; Magalhães, A.; Guimarães, LH; LESSA, M.; E. Lago; Jesus,AR de; Carvalho, EM; Blackwell, JM

    2011-01-01

    Mapping murine genes controlling cutaneous leishmaniasis (CL) identified Fli1 as a candidate influencing resistance to L. major and enhanced wound healing. We examine FLI1 as a gene controlling CL and mucosal leishmaniasis (ML) caused by L. braziliensis in humans. Intron 1 single nucleotide polymorphisms tagging promoter and enhancer elements were analysed in 168 nuclear families (250 CL; 87 ML cases) and replicated in 157 families (402 CL; 39 ML cases). Robust case-pseudocontrol logistic reg...

  11. Bats, Trypanosomes, and Triatomines in Ecuador: New Insights into the Diversity, Transmission, and Origins of Trypanosoma cruzi and Chagas Disease.

    Science.gov (United States)

    Pinto, C Miguel; Ocaña-Mayorga, Sofía; Tapia, Elicio E; Lobos, Simón E; Zurita, Alejandra P; Aguirre-Villacís, Fernanda; MacDonald, Amber; Villacís, Anita G; Lima, Luciana; Teixeira, Marta M G; Grijalva, Mario J; Perkins, Susan L

    2015-01-01

    The generalist parasite Trypanosoma cruzi has two phylogenetic lineages associated almost exclusively with bats-Trypanosoma cruzi Tcbat and the subspecies T. c. marinkellei. We present new information on the genetic variation, geographic distribution, host associations, and potential vectors of these lineages. We conducted field surveys of bats and triatomines in southern Ecuador, a country endemic for Chagas disease, and screened for trypanosomes by microscopy and PCR. We identified parasites at species and genotype levels through phylogenetic approaches based on 18S ribosomal RNA (18S rRNA) and cytochrome b (cytb) genes and conducted a comparison of nucleotide diversity of the cytb gene. We document for the first time T. cruzi Tcbat and T. c. marinkellei in Ecuador, expanding their distribution in South America to the western side of the Andes. In addition, we found the triatomines Cavernicola pilosa and Triatoma dispar sharing shelters with bats. The comparisons of nucleotide diversity revealed a higher diversity for T. c. marinkellei than any of the T. c. cruzi genotypes associated with Chagas disease. Findings from this study increased both the number of host species and known geographical ranges of both parasites and suggest potential vectors for these two trypanosomes associated with bats in rural areas of southern Ecuador. The higher nucleotide diversity of T. c. marinkellei supports a long evolutionary relationship between T. cruzi and bats, implying that bats are the original hosts of this important parasite.

  12. Trapping tsetse flies on water

    Directory of Open Access Journals (Sweden)

    Laveissière C.

    2011-05-01

    Full Text Available Riverine tsetse flies such as Glossina palpalis gambiensis and G. tachinoides are the vectors of human and animal trypanosomoses in West Africa. Despite intimate links between tsetse and water, to our knowledge there has never been any attempt to design trapping devices that would catch tsetse on water. In mangrove (Guinea one challenging issue is the tide, because height above the ground for a trap is a key factor affecting tsetse catches. The trap was mounted on the remains of an old wooden dugout, and attached with rope to nearby branches, thereby allowing it to rise and fall with the tide. Catches showed a very high density of 93.9 flies/”water-trap”/day, which was significantly higher (p < 0.05 than all the catches from other habitats where the classical trap had been used. In savannah, on the Comoe river of South Burkina Faso, the biconical trap was mounted on a small wooden raft anchored to a stone, and catches were compared with the classical biconical trap put on the shores. G. p. gambiensis and G. tachinoides densities were not significantly different from those from the classical biconical one. The adaptations described here have allowed to efficiently catch tsetse on the water, which to our knowledge is reported here for the first time. This represents a great progress and opens new opportunities to undertake studies on the vectors of trypanosomoses in mangrove areas of Guinea, which are currently the areas showing the highest prevalences of sleeping sickness in West Africa. It also has huge potential for tsetse control using insecticide impregnated traps in savannah areas where traps become less efficient in rainy season. The Guinean National control programme has already expressed its willingness to use such modified traps in its control campaigns in Guinea, as has the national PATTEC programme in Burkina Faso during rainy season.

  13. Are flying-foxes coming to town? Urbanisation of the spectacled flying-fox (Pteropus conspicillatus in Australia.

    Directory of Open Access Journals (Sweden)

    Jessica Tait

    Full Text Available Urbanisation of wildlife populations is a process with significant conservation and management implications. While urban areas can provide habitat for wildlife, some urbanised species eventually come into conflict with humans. Understanding the process and drivers of wildlife urbanisation is fundamental to developing effective management responses to this phenomenon. In Australia, flying-foxes (Pteropodidae are a common feature of urban environments, sometimes roosting in groups of tens of thousands of individuals. Flying-foxes appear to be becoming increasingly urbanised and are coming into increased contact and conflict with humans. Flying-fox management is now a highly contentious issue. In this study we used monitoring data collected over a 15 year period (1998-2012 to examine the spatial and temporal patterns of association of spectacled flying-fox (Pteropus conspicillatus roost sites (camps with urban areas. We asked whether spectacled flying-foxes are becoming more urbanised and test the hypothesis that such changes are associated with anthropogenic changes to landscape structure. Our results indicate that spectacled flying-foxes were more likely to roost near humans than might be expected by chance, that over the period of the study the proportion of the flying-foxes in urban-associated camps increased, as did the number of urban camps. Increased urbanisation of spectacled flying-foxes was not related to changes in landscape structure or to the encroachment of urban areas on camps. Overall, camps tended to be found in areas that were more fragmented, closer to human habitation and with more urban land cover than the surrounding landscape. This suggests that urbanisation is a behavioural response rather than driven by habitat loss.

  14. Dielectric properties of fly ash

    Indian Academy of Sciences (India)

    S C Raghavendra; R L Raibagkar; A B Kulkarni

    2002-02-01

    This paper reports the dielectric properties of fly ash. The dielectric measurements were performed as a function of frequency and temperature. The sample of fly ash shows almost similar behaviour in the frequency and temperature range studied. The large value of dielectric constant in the typical frequency range is because of orientation polarization and tight binding force between the ions or atoms in the fly ash. The sample of fly ash is of great scientific and technological interest because of its high value of dielectric constant (104).

  15. Evaluation of ULV applications against Old World sand fly (Diptera: Psychodidae) species in equatorial Kenya

    Science.gov (United States)

    Reducing populations of phlebotomine sand flies in areas prevalent for human leishmaniases is of ongoing importance to US military operations and civilian populations in endemic regions. Collateral reduction of sand flies or human cases of leishmaniases during pesticide campaigns against vectors of ...

  16. Flying over decades

    Science.gov (United States)

    Hoeller, Judith; Issler, Mena; Imamoglu, Atac

    Levy flights haven been extensively used in the past three decades to describe non-Brownian motion of particles. In this presentation I give an overview on how Levy flights have been used across several disciplines, ranging from biology to finance to physics. In our publication we describe how a single electron spin 'flies' when captured in quantum dot using the central spin model. At last I motivate the use of Levy flights for the description of anomalous diffusion in modern experiments, concretely to describe the lifetimes of quasi-particles in Josephson junctions. Finished PhD at ETH in Spring 2015.

  17. Vision in flying insects.

    Science.gov (United States)

    Egelhaaf, Martin; Kern, Roland

    2002-12-01

    Vision guides flight behaviour in numerous insects. Despite their small brain, insects easily outperform current man-made autonomous vehicles in many respects. Examples are the virtuosic chasing manoeuvres male flies perform as part of their mating behaviour and the ability of bees to assess, on the basis of visual motion cues, the distance travelled in a novel environment. Analyses at both the behavioural and neuronal levels are beginning to unveil reasons for such extraordinary capabilities of insects. One recipe for their success is the adaptation of visual information processing to the specific requirements of the behavioural tasks and to the specific spatiotemporal properties of the natural input.

  18. Cyclic AMP effectors in African trypanosomes revealed by genome-scale RNA interference library screening for resistance to the phosphodiesterase inhibitor CpdA.

    Science.gov (United States)

    Gould, Matthew K; Bachmaier, Sabine; Ali, Juma A M; Alsford, Sam; Tagoe, Daniel N A; Munday, Jane C; Schnaufer, Achim C; Horn, David; Boshart, Michael; de Koning, Harry P

    2013-10-01

    One of the most promising new targets for trypanocidal drugs to emerge in recent years is the cyclic AMP (cAMP) phosphodiesterase (PDE) activity encoded by TbrPDEB1 and TbrPDEB2. These genes were genetically confirmed as essential, and a high-affinity inhibitor, CpdA, displays potent antitrypanosomal activity. To identify effectors of the elevated cAMP levels resulting from CpdA action and, consequently, potential sites for adaptations giving resistance to PDE inhibitors, resistance to the drug was induced. Selection of mutagenized trypanosomes resulted in resistance to CpdA as well as cross-resistance to membrane-permeable cAMP analogues but not to currently used trypanocidal drugs. Resistance was not due to changes in cAMP levels or in PDEB genes. A second approach, a genome-wide RNA interference (RNAi) library screen, returned four genes giving resistance to CpdA upon knockdown. Validation by independent RNAi strategies confirmed resistance to CpdA and suggested a role for the identified cAMP Response Proteins (CARPs) in cAMP action. CARP1 is unique to kinetoplastid parasites and has predicted cyclic nucleotide binding-like domains, and RNAi repression resulted in >100-fold resistance. CARP2 and CARP4 are hypothetical conserved proteins associated with the eukaryotic flagellar proteome or with flagellar function, with an orthologue of CARP4 implicated in human disease. CARP3 is a hypothetical protein, unique to Trypanosoma. CARP1 to CARP4 likely represent components of a novel cAMP signaling pathway in the parasite. As cAMP metabolism is validated as a drug target in Trypanosoma brucei, cAMP effectors highly divergent from the mammalian host, such as CARP1, lend themselves to further pharmacological development.

  19. Fly ash quality and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Barta, L.E.; Lachner, L.; Wenzel, G.B. [Inst. for Energy, Budapest (Hungary); Beer, M.J. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

    1995-12-01

    The quality of fly ash is of considerable importance to fly ash utilizers. The fly ash puzzolanic activity is one of the most important properties that determines the role of fly ash as a binding agent in the cementing process. The puzzolanic activity, however is a function of fly ash particle size and chemical composition. These parameters are closely related to the process of fly ash formation in pulverized coal fired furnaces. In turn, it is essential to understand the transformation of mineral matter during coal combustion. Due to the particle-to-particle variation of coal properties and the random coalescence of mineral particles, the properties of fly ash particles e.g. size, SiO{sub 2} content, viscosity can change considerably from particle to particle. These variations can be described by the use of the probability theory. Since the mean values of these randomly changing parameters are not sufficient to describe the behavior of individual fly ash particles during the formation of concrete, therefore it is necessary to investigate the distribution of these variables. Examples of these variations were examined by the Computer Controlled Scanning Electron Microscopy (CCSEM) for particle size and chemical composition for Texas lignite and Eagel Butte mineral matter and fly ash. The effect of combustion on the variations of these properties for both the fly ash and mineral matter were studied by using a laminar flow reactor. It is shown in our paper, that there are significant variations (about 40-50% around the mean values) of the above-listed properties for both coal samples. By comparing the particle size and chemical composition distributions of the mineral matter and fly ash, it was possible to conclude that for the Texas lignite mineral matter, the combustion did not effect significantly the distribution of these properties, however, for the Eagel Butte coal the combustion had a major impact on these mineral matter parameters.

  20. Role of bacteria in the oviposition behaviour and larval development of stable flies.

    Science.gov (United States)

    Romero, A; Broce, A; Zurek, L

    2006-03-01

    Stable flies, Stomoxys calcitrans (L.), are the most important pests of cattle in the United States. However, adequate management strategies for stable flies, especially for pastured cattle, are lacking. Microbial/symbiont-based approaches offer novel venues for management of insect pests and/or vector-borne human and animal pathogens. Unfortunately, the fundamental knowledge of stable fly-microbial associations and their effect on stable fly biology is lacking. In this study, stable flies laid greater numbers of eggs on a substrate with an active microbial community (> 95% of total eggs oviposited) than on a sterilized substrate. In addition, stable fly larvae could not develop in a sterilized natural or artificial substrate/medium. Bacteria were isolated and identified from a natural stable fly oviposition/developmental habitat and their individual effect on stable fly oviposition response and larval development was evaluated in laboratory bioassays. Of nine bacterial strains evaluated in the oviposition bioassays, Citrobacter freundii stimulated oviposition to the greatest extent. C. freundii also sustained stable fly development, but to a lesser degree than Serratia fanticola. Serratia marcescens and Aeromonas spp. neither stimulated oviposition nor supported stable fly development. These results demonstrate a stable fly bacterial symbiosis; stable fly larval development depends on a live microbial community in the natural habitat, and stable fly females are capable of selecting an oviposition site based on the microbially derived stimuli that indicate the suitability of the substrate for larval development. This study shows a promising starting point for exploiting stable fly-bacterial associations for development of novel approaches for stable fly management.

  1. Physics of flying

    Science.gov (United States)

    Vetrone, Jim

    2015-05-01

    Column editor's note: As the school year comes to a close, it is important to start thinking about next year. One area that you want to consider is field trips. Many institutions require that teachers plan for a field trip well in advance. Keeping that in mind, I asked Jim Vetrone to write an article about the fantastic field trip he takes his AP Physics students on. I had the awesome opportunity to attend a professional development day that Jim arranged at iFLY in the Chicago suburbs. The experience of "flying" in a wind tunnel was fabulous. Equally fun was watching the other physics teachers come up with experiments to have the professional "flyers" perform in the tube. I could envision my students being similarly excited about the experience and about the development of their own experiments. After I returned to school, I immediately began the process of trying to get this field trip approved for the 2015-16 school year. I suggest that you start your process as well if you hope to try a new field trip next year. The key to getting the approval, in my experience, is submitting a proposal early that includes supporting documentation from sources. Often I use NGSS or state standards as justifications for my field trips. I have also quoted College Board expectations for AP Physics 1 and 2 in my documents when requesting an unusual field trip.quote>

  2. The Ewing's sarcoma EWS/FLI-1 fusion gene encodes a more potent transcriptional activator and is a more powerful transforming gene than FLI-1.

    OpenAIRE

    May, W A; Lessnick, S L; Braun, B S; Klemsz, M; Lewis, B. C.; Lunsford, L B; Hromas, R; Denny, C T

    1993-01-01

    EWS/FLI-1 is a chimeric protein formed by a tumor-specific 11;22 translocation found in both Ewing's sarcoma and primitive neuroectodermal tumor of childhood. EWS/FLI-1 has been shown to be a potent transforming gene, suggesting that it plays an important role in the genesis of these human tumors. We now demonstrate that EWS/FLI-1 has the characteristics of an aberrant transcription factor. Subcellular fractionation experiments localized the EWS/FLI-1 protein to the nucleus of primitive neuro...

  3. FlyBase at 25: looking to the future

    Science.gov (United States)

    Gramates, L. Sian; Marygold, Steven J.; dos Santos, Gilberto; Urbano, Jose-Maria; Antonazzo, Giulia; Matthews, Beverley B.; Rey, Alix J.; Tabone, Christopher J.; Crosby, Madeline A.; Emmert, David B.; Falls, Kathleen; Goodman, Joshua L.; Hu, Yanhui; Ponting, Laura; Schroeder, Andrew J.; Strelets, Victor B.; Thurmond, Jim; Zhou, Pinglei

    2017-01-01

    Since 1992, FlyBase (flybase.org) has been an essential online resource for the Drosophila research community. Concentrating on the most extensively studied species, Drosophila melanogaster, FlyBase includes information on genes (molecular and genetic), transgenic constructs, phenotypes, genetic and physical interactions, and reagents such as stocks and cDNAs. Access to data is provided through a number of tools, reports, and bulk-data downloads. Looking to the future, FlyBase is expanding its focus to serve a broader scientific community. In this update, we describe new features, datasets, reagent collections, and data presentations that address this goal, including enhanced orthology data, Human Disease Model Reports, protein domain search and visualization, concise gene summaries, a portal for external resources, video tutorials and the FlyBase Community Advisory Group. PMID:27799470

  4. Refractive Index of Fly Rhabdomeres

    NARCIS (Netherlands)

    Stavenga, D.G.

    1974-01-01

    The refractive index reported previously for the rhabdomeres of flies (1.349) has been corrected for waveguide effects. The presented correction method has yielded n1 = 1.365 ± 0.006. It is argued that an acceptable estimate for the refractive index of the inhomogeneous surroundings of fly

  5. In vitro activity of 2-pyridinecarboxylic acid against trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus = Atividade in vitro do ácido 2-piridinocarboxílico em tripanossoma do subgênero Schizotrypanum isolado do morcego Phyllostomus hastatus

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Ceridóreo Corrêa

    2011-09-01

    Full Text Available The effect of 2-pyridinecarboxylic acid (picolinic acid on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 ƒÊg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 ƒÊg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was275 ƒÊg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a competitive inhibition. Furthermore, two anti-Trypanosoma (Schizotrypanum cruzi drugs were also evaluated with regard to bat trypanosome growth. Benznidazole, at 50 ƒÊg mL-1, inhibited epimastigote growth by 90% after 12 days incubation. Nifurtimox, at the same concentration, caused 96% growth inhibition after four days incubation. Corroborating a previous study, bat trypanosomes are a good model for screening new trypanocidal compounds. Moreover, they can be used to study many biological processes common to human pathogenic trypanosomatids.O efeito do acido 2- piridinocarboxilico (acido picolinico sobre um tripanossoma do subgenero Schizotrypanum isolado do morcego Phyllostomus hastatus foi determinado neste estudo. O acido picolinico, na concentracao de 50 ƒÊg mL-1, inibiu 99% do crescimento de epimastigotas apos 12 dias de incubacao. Alem disso, houve um decrescimo de 50 e 100% na mobilidade dos tripomastigotas apos 6 e 24h, respectivamente, em presenca de acido picolinico na concentracao de 50 ƒÊg mL-1. A concentracao citotoxica 50% para celulas HEp-2 foi de 275 ƒÊg mL-1 apos quatro dias de incubacao. Esses resultados indicam maior toxicidade contra os tripanossomas. O efeito inibitoriodo acido picolinico sobre o crescimento de

  6. Laser system for identification, tracking, and control of flying insects

    Science.gov (United States)

    Flying insects are common vectors for transmission of pathogens and inflict significant harm on humans in large parts of the developing world. Besides the direct impact to humans, these pathogens also cause harm to crops and result in agricultural losses. Here, we present a laser-based system that c...

  7. On-the-fly selection of cell-specific enhancers, genes, miRNAs and proteins across the human body using SlideBase

    DEFF Research Database (Denmark)

    Ienasescu, Hans; Li, Kang; Andersson, Robin;

    2016-01-01

    Genomics consortia have produced large datasets profiling the expression of genes, micro-RNAs, enhancers and more across human tissues or cells. There is a need for intuitive tools to select subsets of such data that is the most relevant for specific studies. To this end, we present Slide...... for individual cell types/tissues, producing sets of genes, enhancers etc. which satisfy these constraints. Changes in slider settings result in simultaneous changes in the selected sets, updated in real time. SlideBase is linked to major databases from genomics consortia, including FANTOM, GTEx, The Human...

  8. In vitro-in vivo studies on anti-trypanosomal potentials of Zapoteca portoricensis

    Institute of Scientific and Technical Information of China (English)

    Nwodo NJ; Omeje EO; Brun R

    2009-01-01

    Objective:Aqueous extracts of Zapoteca portoricensis are used traditionally as antidiarrhea agent and in the treatment of diverse gastrointestinal disorders here in Nigeria specifically,the southern part.Similarly,the a-queous extract of the plant is also used traditionally as anticonvulsant,antispasmodic and in the treatment of tonsillitis.Recently too,the anti-inflammatory and antimicrobial activities of the methanol extracts of the root of Zapoteca portoricensis was reported.In this research,we are set to investigate the trypanocidal activity of Zapoteca portoricensis.Methods:The methanol extract of the root of Zapoteca portoricensis was investigated for both in vitro and in vivo trypanocidal activity following established models.In summary,phytochemical analy-sis was carried out on both the crude powdered root and on the methanol extract following standard procedures. The oral acute toxicity test (LD50 )of the crude methanol extract was determined according to the method de-scribed by Lorke (1983).Albino mice (17g-21g)of either sex were used.The methanol extract was suspen-ded in 3 % v /v tween 85 and administered orally at doses of 10 mg/kg,100 mg/kg and 1 000 mg/kg to three groups of mice (n =3).The animals were observed for 24 hours.Based on the result obtained in this initial test,doses of 4 mg/kg,6 mg/kg,and 8 mg/kg were administered to three different mice.The LD50 was calcu-lated as the geometric mean of the lowest dose killing a mouse and the highest dose showing no death.The in-vivo /in-vitro anti-trypanosomal evaluations were carried out in experimental animals and tissue cell culture re-spectively.Results:The result of the in vitro studies shows the inhibitive concentration-50(IC-50)against Trypanosoma brucei rhodesiense (T.b.rhodesiense)to be 0.372 mg/kg,while the control drug melarsoprol was 0.006 mg/kg.On Trypanosoma brucei brucei (T .cruzi),the IC-50 is 6.42 mg/kg against 0.87 of the ref-erence drug Benznidazole.The cyctotoxicity on L-6 cells

  9. The impact of host starvation on parasite development and population dynamics in an intestinal trypanosome parasite of bumble bees.

    Science.gov (United States)

    Logan, A; Ruiz-González, M X; Brown, M J F

    2005-06-01

    Host nutrition plays an important role in determining the development and success of parasitic infections. While studies of vertebrate hosts are accumulating, little is known about how host nutrition affects parasites of invertebrate hosts. Crithidia bombi is a gut trypanosome parasite of the bumble bee, Bombus terrestris and here we use it as a model system to determine the impact of host nutrition on the population dynamics and development of micro-parasites in invertebrates. Pollen-starved bees supported significantly smaller populations of the parasite. In pollen-fed bees the parasite showed a temporal pattern in development, with promastigote transmission stages appearing at the start of the infection and gradually being replaced by choanomastigote and amastigote forms. In pollen-starved bees this developmental process was disrupted, and there was no pattern in the appearance of these three forms. We discuss the implications of these results for parasite transmission, and speculate about the mechanisms behind these changes.

  10. Genome-Wide Comparative Analysis of Chemosensory Gene Families in Five Tsetse Fly Species.

    Directory of Open Access Journals (Sweden)

    Rosaline Macharia

    2016-02-01

    Full Text Available For decades, odour-baited traps have been used for control of tsetse flies (Diptera; Glossinidae, vectors of African trypanosomes. However, differential responses to known attractants have been reported in different Glossina species, hindering establishment of a universal vector control tool. Availability of full genome sequences of five Glossina species offers an opportunity to compare their chemosensory repertoire and enhance our understanding of their biology in relation to chemosensation. Here, we identified and annotated the major chemosensory gene families in Glossina. We identified a total of 118, 115, 124, and 123 chemosensory genes in Glossina austeni, G. brevipalpis, G. f. fuscipes, G. pallidipes, respectively, relative to 127 reported in G. m. morsitans. Our results show that tsetse fly genomes have fewer chemosensory genes when compared to other dipterans such as Musca domestica (n>393, Drosophila melanogaster (n = 246 and Anopheles gambiae (n>247. We also found that Glossina chemosensory genes are dispersed across distantly located scaffolds in their respective genomes, in contrast to other insects like D. melanogaster whose genes occur in clusters. Further, Glossina appears to be devoid of sugar receptors and to have expanded CO2 associated receptors, potentially reflecting Glossina's obligate hematophagy and the need to detect hosts that may be out of sight. We also identified, in all species, homologs of Ir84a; a Drosophila-specific ionotropic receptor that promotes male courtship suggesting that this is a conserved trait in tsetse flies. Notably, our selection analysis revealed that a total of four gene loci (Gr21a, GluRIIA, Gr28b, and Obp83a were under positive selection, which confers fitness advantage to species. These findings provide a platform for studies to further define the language of communication of tsetse with their environment, and influence development of novel approaches for control.

  11. Accurate Segmentation for Infrared Flying Bird Tracking

    Institute of Scientific and Technical Information of China (English)

    ZHENG Hong; HUANG Ying; LING Haibin; ZOU Qi; YANG Hao

    2016-01-01

    Bird strikes present a huge risk for air ve-hicles, especially since traditional airport bird surveillance is mainly dependent on inefficient human observation. For improving the effectiveness and efficiency of bird monitor-ing, computer vision techniques have been proposed to detect birds, determine bird flying trajectories, and pre-dict aircraft takeoff delays. Flying bird with a huge de-formation causes a great challenge to current tracking al-gorithms. We propose a segmentation based approach to enable tracking can adapt to the varying shape of bird. The approach works by segmenting object at a region of inter-est, where is determined by the object localization method and heuristic edge information. The segmentation is per-formed by Markov random field, which is trained by fore-ground and background mixture Gaussian models. Exper-iments demonstrate that the proposed approach provides the ability to handle large deformations and outperforms the m ost state-of-the-art tracker in the infrared flying bird tracking problem.

  12. Mutagenicity and genotoxicity of coal fly ash water leachate

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, R.; Mukherjee, A. [University of Calcutta, Calcutta (India). Dept. of Botany

    2009-03-15

    Fly ash is a by-product of coal-fired electricity generation plants. The prevalent practice of disposal is as slurry of ash and water to storage or ash ponds located near power stations. This has lain to waste thousands of hectares of land all over the world. Since leaching is often the cause of off-site contamination and pathway of introduction into the human environment, a study on the genotoxic effects of fly ash leachate is essential. Leachate prepared from the fly ash sample was analyzed for metal content, and tested for mutagenicity and genotoxicity. Analyses of metals show predominance of the metals - sodium, silicon, potassium, calcium, magnesium, iron, manganese, zinc, and sulphate. The Ames Salmonella mutagenicity assay, a short-term bacterial reverse mutation assay, was conducted on two-tester strains of Salmonella typhimurium strains TA97a and TA102. For genotoxicity, the alkaline version of comet assay on fly ash leachate was carried in vitro on human blood cells and in vivo on Nicotiana plants. The leachate was directly mutagenic and induced significantconcentration-dependent increases in DNA damage in whole blood cells, lymphocytes, and in Nicotiana plants. The comet parameters show increases in tail DNA percentage (%), tail length (mu m), and olive tail moment (arbitrary units). Our results indicate that leachate from fly ash dumpsites has the genotoxic potential and may lead to adverse effects on vegetation and on the health of exposed human populations.

  13. Roll Control in Fruit Flies

    CERN Document Server

    Beatus, Tsevi; Cohen, Itai

    2014-01-01

    Due to aerodynamic instabilities, stabilizing flapping flight requires ever-present fast corrective actions. Here we investigate how flies control body roll angle, their most susceptible degree of freedom. We glue a magnet to each fly, apply a short magnetic pulse that rolls it in mid-air, and film the corrective maneuver. Flies correct perturbations of up to $100^{\\circ}$ within $30\\pm7\\mathrm{ms}$ by applying a stroke-amplitude asymmetry that is well described by a linear PI controller. The response latency is $\\sim5\\mathrm{ms}$, making the roll correction reflex one of the fastest in the animal kingdom.

  14. Efficient Recreation of t(11;22 EWSR1-FLI1+ in Human Stem Cells Using CRISPR/Cas9

    Directory of Open Access Journals (Sweden)

    Raul Torres-Ruiz

    2017-05-01

    Full Text Available Efficient methodologies for recreating cancer-associated chromosome translocations are in high demand as tools for investigating how such events initiate cancer. The CRISPR/Cas9 system has been used to reconstruct the genetics of these complex rearrangements at native loci while maintaining the architecture and regulatory elements. However, the CRISPR system remains inefficient in human stem cells. Here, we compared three strategies aimed at enhancing the efficiency of the CRISPR-mediated t(11;22 translocation in human stem cells, including mesenchymal and induced pluripotent stem cells: (1 using end-joining DNA processing factors involved in repair mechanisms, or (2 ssODNs to guide the ligation of the double-strand break ends generated by CRISPR/Cas9; and (3 all-in-one plasmid or ribonucleoprotein complex-based approaches. We report that the generation of targeted t(11;22 is significantly increased by using a combination of ribonucleoprotein complexes and ssODNs. The CRISPR/Cas9-mediated generation of targeted t(11;22 in human stem cells opens up new avenues in modeling Ewing sarcoma.

  15. Managing the Fruit Fly Experiment.

    Science.gov (United States)

    Jeszenszky, Arleen W.

    1997-01-01

    Describes a sophisticated version of the fruit fly experiment for teaching concepts about genetics to biology students. Provides students with the opportunity to work with live animals over an extended period. (JRH)

  16. Quantitative proteomics on the fly

    NARCIS (Netherlands)

    Gouw, J.W.

    2009-01-01

    The development of multicellular organisms is characterized by complex processes that progressively transform essentially a single cell into a creature with complicated structures and highly specialized functions. The fruit fly Drosophila melanogaster provides an excellent model system to investigat

  17. On-the-fly selection of cell-specific enhancers, genes, miRNAs and proteins across the human body using SlideBase.

    Science.gov (United States)

    Ienasescu, Hans; Li, Kang; Andersson, Robin; Vitezic, Morana; Rennie, Sarah; Chen, Yun; Vitting-Seerup, Kristoffer; Lagoni, Emil; Boyd, Mette; Bornholdt, Jette; de Hoon, Michiel J L; Kawaji, Hideya; Lassmann, Timo; Hayashizaki, Yoshihide; Forrest, Alistair R R; Carninci, Piero; Sandelin, Albin

    2016-01-01

    Genomics consortia have produced large datasets profiling the expression of genes, micro-RNAs, enhancers and more across human tissues or cells. There is a need for intuitive tools to select subsets of such data that is the most relevant for specific studies. To this end, we present SlideBase, a web tool which offers a new way of selecting genes, promoters, enhancers and microRNAs that are preferentially expressed/used in a specified set of cells/tissues, based on the use of interactive sliders. With the help of sliders, SlideBase enables users to define custom expression thresholds for individual cell types/tissues, producing sets of genes, enhancers etc. which satisfy these constraints. Changes in slider settings result in simultaneous changes in the selected sets, updated in real time. SlideBase is linked to major databases from genomics consortia, including FANTOM, GTEx, The Human Protein Atlas and BioGPS.Database URL: http://slidebase.binf.ku.dk.

  18. Subtropical Fruit Fly Invasions into Temperate Fruit Fly Territory in California's San Joaquin Valley

    Science.gov (United States)

    Subtropical fruit fly species including peach fruit fly, Bactrocera zonata (Saunders); melon fly, B. cucurbitae (Coquillett); oriental fruit fly, B. dorsalis (Hendel); and Mediterranean fruit fly, Ceratitis capitata Weidemann, have been detected in the past decade in the San Joaquin Valley of Califo...

  19. Relative potency of various insecticides for use in ATSBs against mosquitoes and sand flies

    Science.gov (United States)

    Mosquitoes and sand flies are important throughout the world as nuisance pests and vectors of a variety of human and livestock diseases. Control efforts are limited often to adulticide sprays and larvicides, however, environmental concerns restrict their use. Both mosquitoes and sand flies need to...

  20. Evaluation of ULV applications against Old World sand fly species in equatorial Kenya

    Science.gov (United States)

    Reducing populations of phlebotomine sand flies in areas prevalent for leishmaniases is of ongoing importance to U.S. military operations. Collateral reduction of sand flies or human cases of leishmaniases during pesticide campaigns against vectors of malaria indicate that residuals like DDT can be ...

  1. Flying in Two Dimensions

    CERN Document Server

    Prakash, Manu

    2011-01-01

    Diversity and specialization of behavior in insects is unmatched. Insects hop, walk, run, jump, row, swim, glide and fly to propel themselves in a variety of environments. We have uncovered an unusual mode of propulsion of aerodynamic flight in two dimensions in Waterlilly Beetles \\emph{(Galerucella)}. The adult beetles, often found in water lilly ponds, propel themselves strictly in a two-dimensional plane on the surface of water via flapping wing flight. Here we analyze the aerodynamics of this peculiar flight mode with respect to forces exerted on the organism during flight. The complexity of 2-D flight is captured by accounting for additional forces beyond gravitational, thrust, lift and drag, exerted on the insect body in 3D flight. Understanding this constrained propulsion mode requires accounting for viscous drag, surface tension, buoyancy force, and capillary-wave drag. Moreover, dramatic differences exist in the magnitude of the resultant forces in 2D vs. 3D flight. Here, in this fluid dynamics video...

  2. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  3. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  4. Myiasis with Lund's fly (Cordylobia rodhaini) in travelers.

    Science.gov (United States)

    Tamir, Jeremy; Haik, J; Schwartz, Eli

    2003-01-01

    Myiasis is an infestation of human tissue by the larvae of certain flies. There are many forms of myiasis, including localized furuncular myiasis, creeping dermal myiasis and wound and body cavity myiasis.1 Cordylobia anthropophaga (the Tumbu fly) and Dermatobia hominis (the human botfly) are the most common causes of myiasis in Africa and tropical America respectively. The genus Cordylobia also contains two less common species, C. ruandae and C. rodhaini. The usual hosts of C. rodhaini are various mammals (particularly rodents), and and humans are accidentally infested. Figure 1 shows the life cycle of C. rodhaini, which occurs over 55 to -67 days.3 The female fly deposits her eggs on dry sand polluted with the excrement of animals or on human clothing. In about 3 days, the larva is activated by the warm body of the host, hatches and invades the skin. As the larva matures, it induces a furuncular swelling. In 12 to -15 days, the larva reaches a length of about 23 mm, exits the skin and falls to the ground to pupate. The adult fly emerges in 23 to -26 days, and the life cycle resumes. In humans, the skin lesion starts as a red papule that gradually enlarges and develops into a furuncle. In the center of the lesion an opening forms, through which the larva breaths and discharges its serosanguinous feces. The lesion is associated with increasing pain until the larva exits the skin. The disease is usually uncomplicated and self-limiting.

  5. Amino acids as taste stimuli for tsetse flies

    NARCIS (Netherlands)

    van der Goes van Naters, W.M; den Otter, C.J

    This paper reports the responses of taste cells on the legs of the blood-feeding tsetse fly Glossina fuscipes fuscipes Newstead 1910 (Diptera: Glossinidae) to twenty protein amino acids and to their mixture as it is present in human;sweat. It is investigated whether the mixture is sensed differently

  6. From Self-Flying Helicopters to Classrooms of the Future

    Science.gov (United States)

    Young, Jeffrey R.

    2012-01-01

    On a summer day four years ago, a Stanford University computer-science professor named Andrew Ng held an unusual air show on a field near the campus. His fleet of small helicopter drones flew under computer control, piloted by artificial-intelligence software that could teach itself to fly after watching a human operator. By the end of the day,…

  7. Safety management of formation flying in an aerobatic team

    Directory of Open Access Journals (Sweden)

    Róbert ROZENBERG

    2013-12-01

    Full Text Available The article is focused on explaining the notion of safety from the aspect of generally applicable standards established by the ICAO. It describes the role of human factor played by the pilot´s personality in an aerobatic team by way of determining the individual traits of team members as pre–requisites of mastering formation flying.

  8. Expression and Biochemical Properties of a Recombinant Acetylcholinesterase 1 of the Sand Fly, Phlebotomus papatasi (Scopoli) Insensitive to Organophosphate Inhibition

    Science.gov (United States)

    Phlebotomine sand flies are small hematophagous flies present throughout tropical and subtropical areas of the world and are vectors of human and zoonotic leishmaniases. Human cutaneous leishmaniasis is a debilitating disease presenting major problems for U.S. military operations in the Middle East,...

  9. Laser system for identification, tracking, and control of flying insects.

    Science.gov (United States)

    Mullen, Emma R; Rutschman, Phillip; Pegram, Nathan; Patt, Joseph M; Adamczyk, John J; Johanson, 3ric

    2016-05-30

    Flying insects are common vectors for transmission of pathogens and inflict significant harm to humans and agricultural production in many parts of the world. We present proof of principle for an optical system capable of highly specific vector control. This system utilizes a combination of optical sources, detectors, and sophisticated software to search, detect, and identify flying insects in real-time, with the capability of eradication using a lethal laser pulse. We present data on two insect species to show species distinction; Diaphorina citri, a vector of the causal agent of citrus greening disease, and Anopheles stephensi, a malaria vector.

  10. Fiber optics that fly

    Science.gov (United States)

    Wilcox, Michael J.; Thelen, Donald C., Jr.

    1996-11-01

    The need for autonomous systems to work under unanticipated conditions requires the use of smart sensors. High resolution systems develop tremendous computational loads. Inspiration from animal vision systems can guide us in developing preprocessing approaches implementable in real time with high resolution and deduced computational load. Given a high quality optical path and a 2D array of photodetectors, the resolution of a digital image is determined by the density of photodetectors sampling the image. In order to reconstruct an image, resolution is limited by the distance between adjacent detectors. However, animal eyes resolve images 10-100 times better than either the acceptance angle of a single photodetector or the center-to-center distance between neighboring photodetectors. A new model of the fly's visual system emulates this improved performance, offering a different approach to subpixel resolution. That an animal without a cortex is capable of this performance suggests that high level computation is not involved. The model takes advantage of a photoreceptor cell's internal structure for capturing light. This organelle is a waveguide. Neurocircuitry exploits the waveguide's optical nonlinearities, namely in the shoulder region of its gaussian sensitivity-profile, to extract high resolution information from the visual scene. The receptive fields of optically disparate inputs overlap in space. Photoreceptor input is continuous rather than discretely sampled. The output of the integrating module is a signal proportional to the position of the target within the detector array. For tracking a point source, resolution is 10 times better than the detector spacing. For locating absolute position and orientation of an edge, the model performs similarly. Analog processing is used throughout. Each element is an independent processor of local luminance. Information processing is in real time with continuous update. This processing principle will be reproduced in an

  11. Fly-in/Fly-out: Implications for Community Sustainability

    Directory of Open Access Journals (Sweden)

    Keith Storey

    2010-04-01

    Full Text Available “Fly-in/fly-out” is a form of work organization that has become the standard model for new mining, petroleum and other types of resource development in remote areas. In many places this “no town” model has replaced that of the “new town.” The work system has both beneficial and adverse implications for the sustainability of both existing communities near new resource developments and for the more distant communities from which workers are drawn. This paper explores these outcomes drawing upon examples from North America and Australia.

  12. Escherichia coli fliAZY operon.

    OpenAIRE

    Mytelka, D S; Chamberlin, M J

    1996-01-01

    We have cloned the Escherichia coli fliAZY operon, which contains the fliA gene (the alternative sigma factor sigma F) and two novel genes, fliZ and fliY. Transcriptional mapping of this operon shows two start sites, one of which is preceded by a canonical E sigma F-dependent consensus and is dependent on sigma F for expression in vivo and in vitro. We have overexpressed and purified sigma F and demonstrated that it can direct core polymerase to E sigma F-dependent promoters. FliZ and FliY ar...

  13. Trypanosomosis in The Gambia: prevalence in working horses and donkeys detected by whole genome amplification and PCR, and evidence for interactions between trypanosome species

    Directory of Open Access Journals (Sweden)

    Jallow Jibril

    2008-02-01

    Full Text Available Abstract Background The Gambia has an increasing population of equidae largely used for agriculture and transportation. A review of cases at The Gambian Horse and Donkey Trust (GHDT indicated that a common reason for presentation is a poorly defined medical condition often attributed to trypanosomosis. There are few reports describing the prevalence or the range of clinical signs associated with infection with different species of trypanosomes in horses and donkeys, but given the importance of these animals, the role of trypanosomosis requires investigation. Results In total 241 animals from the Central River Division in The Gambia (183 horses and 58 donkeys were screened using Whole Genome Amplification (WGA followed by trypanosome species identification using polymerase chain reaction (PCR. The results indicated overall trypanosome prevalence of 91%; with an infection rate of 31% for Trypanosoma congolense Savannah, 87% for Trypanosoma vivax and 18% for Trypanosoma brucei sp. Multiple species were present in 43% of infections. Microscopy had a good specificity (100% and positive predictive value (100% for trypanosome detection, but the sensitivity (20% and negative predictive value (10.5% were low relative to PCR-based diagnosis. Infection with T congolense showed the greatest negative effect on packed cell volume (PCV, while infection with T. brucei sp also had a significant, although lesser, negative effect on PCV. In addition, cases positive by microscopy were associated with significantly lower PCV. However, concurrent infection with T. vivax appeared to cause less effect on PCV, compared to animals infected with T. congolense alone. Conclusion The prevalence of Trypanosomosis was high in both horses and donkeys. Infection with T. congolense appeared to have the greatest clinical significance, while T. vivax infection may be of limited clinical significance in this population. Indeed, there is evidence of T. vivax co-infection ameliorating

  14. Breeding sites of Phlebotomus sergenti, the sand fly vector of cutaneous leishmaniasis in the Judean Desert.

    Directory of Open Access Journals (Sweden)

    Aviad Moncaz

    Full Text Available Phlebotomine sand flies transmit Leishmania, phlebo-viruses and Bartonella to humans. A prominent gap in our knowledge of sand fly biology remains the ecology of their immature stages. Sand flies, unlike mosquitoes do not breed in water and only small numbers of larvae have been recovered from diverse habitats that provide stable temperatures, high humidity and decaying organic matter. We describe studies designed to identify and characterize sand fly breeding habitats in a Judean Desert focus of cutaneous leishmaniasis. To detect breeding habitats we constructed emergence traps comprising sand fly-proof netting covering defined areas or cave openings. Large size horizontal sticky traps within the confined spaces were used to trap the sand flies. Newly eclosed male sand flies were identified based on their un-rotated genitalia. Cumulative results show that Phlebotomus sergenti the vector of Leishmania tropica rests and breeds inside caves that are also home to rock hyraxes (the reservoir hosts of L. tropica and several rodent species. Emerging sand flies were also trapped outside covered caves, probably arriving from other caves or from smaller, concealed cracks in the rocky ledges close by. Man-made support walls constructed with large boulders were also identified as breeding habitats for Ph. sergenti albeit less important than caves. Soil samples obtained from caves and burrows were rich in organic matter and salt content. In this study we developed and put into practice a generalized experimental scheme for identifying sand fly breeding habitats and for assessing the quantities of flies that emerge from them. An improved understanding of sand fly larval ecology should facilitate the implementation of effective control strategies of sand fly vectors of Leishmania.

  15. Control of free-flying space robot manipulator systems

    Science.gov (United States)

    Cannon, Robert H., Jr.

    1990-01-01

    New control techniques for self contained, autonomous free flying space robots were developed and tested experimentally. Free flying robots are envisioned as a key element of any successful long term presence in space. These robots must be capable of performing the assembly, maintenance, and inspection, and repair tasks that currently require human extravehicular activity (EVA). A set of research projects were developed and carried out using lab models of satellite robots and a flexible manipulator. The second generation space robot models use air cushion vehicle (ACV) technology to simulate in 2-D the drag free, zero g conditions of space. The current work is divided into 5 major projects: Global Navigation and Control of a Free Floating Robot, Cooperative Manipulation from a Free Flying Robot, Multiple Robot Cooperation, Thrusterless Robotic Locomotion, and Dynamic Payload Manipulation. These projects are examined in detail.

  16. Taste and pheromone perception in the fruit fly Drosophila melanogaster.

    Science.gov (United States)

    Ebbs, Michelle L; Amrein, Hubert

    2007-08-01

    Taste is an essential sense for detection of nutrient-rich food and avoidance of toxic substances. The Drosophila melanogaster gustatory system provides an excellent model to study taste perception and taste-elicited behaviors. "The fly" is unique in the animal kingdom with regard to available experimental tools, which include a wide repertoire of molecular-genetic analyses (i.e., efficient production of transgenics and gene knockouts), elegant behavioral assays, and the possibility to conduct electrophysiological investigations. In addition, fruit flies, like humans, recognize sugars as a food source, but avoid bitter tasting substances that are often toxic to insects and mammals alike. This paper will present recent research progress in the field of taste and contact pheromone perception in the fruit fly. First, we shall describe the anatomical properties of the Drosophila gustatory system and survey the family of taste receptors to provide an appropriate background. We shall then review taste and pheromone perception mainly from a molecular genetic perspective that includes behavioral, electrophysiological and imaging analyses of wild type flies and flies with genetically manipulated taste cells. Finally, we shall provide an outlook of taste research in this elegant model system for the next few years.

  17. Development of resazurin-based assay in 384-well format for high throughput whole cell screening of Trypanosoma brucei rhodesiense strain STIB 900 for the identification of potential anti-trypanosomal agents.

    Science.gov (United States)

    Lim, Kah Tee; Zahari, Zuriati; Amanah, Azimah; Zainuddin, Zafarina; Adenan, Mohd Ilham

    2016-03-01

    To accelerate the discovery of novel leads for the treatment of Human African Trypanosomiasis (HAT), it is necessary to have a simple, robust and cost-effective assay to identify positive hits by high throughput whole cell screening. Most of the fluorescence assay was made in black plate however in this study the HTS assay developed in 384-well format using clear plate and black plate, for comparison. The HTS assay developed is simple, sensitive, reliable and reproducible in both types of plates. Assay robustness and reproducibility were determined under the optimized conditions in 384-well plate was well tolerated in the HTS assay, including percentage of coefficient of variation (% CV) of 4.68% and 4.74% in clear and black 384-well plate, signal-to-background ratio (S/B) of 12.75 in clear 384-well plate and 12.07 in black 384-well plate, Z' factor of 0.79 and 0.82 in clear 384-well plate and black 384-well plate, respectively and final concentration of 0.30% dimethylsulfoxide (DMSO) in both types of plate. Drug sensitivity was found to be comparable to the reported anti-trypanosomal assay in 96-well format. The reproducibility and sensitivity of this assay make it compliant to automated liquid handler use in HTS applications.

  18. Dermatobia, the neotropical warble fly.

    Science.gov (United States)

    Sancho, E

    1988-09-01

    The neotropical warble fly, Dermatobia hominis (Fig. 1), has plagued neotropical America since preColombian times, and has become an economically important pest causing substantial losses to the meat, milk and leather industries from northern Mexico down to northern Argentina. Its life cycle (Box 1) is astonishingly complex, requiring another insect as a phoretic carrier of its eggs to the skin of its mammal hosts. Here Eugenio Sancho discusses factors that contribute to the current economic and public health importance of this myiasis-causing fly.

  19. Susceptibility of low-chill blueberry cultivars to Mediterranean fruit fly, oriental fruit fly, and melon fly (Diptera: Tephritidae).

    Science.gov (United States)

    Follett, Peter A; Zee, Francis T; Hamasaki, Randall T; Hummer, Kim; Nakamoto, Stuart T

    2011-04-01

    No-choice tests were conducted to determine whether fruit of southern highbush blueberry, Vaccinium corymbosum L., hybrids are hosts for three invasive tephritid fruit flies in Hawaii. Fruit of various blueberry cultivars was exposed to gravid female flies of Bactrocera dorsalis Hendel (oriental fruit fly), Ceratitis capitata (Wiedemann) (Mediterranean fruit fly), or Bactrocera cucurbitae Coquillet (melon fly) in screen cages outdoors for 6 h and then held on sand in the laboratory for 2 wk for pupal development and adult emergence. Each of the 15 blueberry cultivars tested were infested by oriental fruit fly and Mediterranean fruit fly, confirming that these fruit flies will oviposit on blueberry fruit and that blueberry is a suitable host for fly development. However, there was significant cultivar variation in susceptibility to fruit fly infestation. For oriental fruit fly, 'Sapphire' fruit produced an average of 1.42 puparia per g, twice as high as that of the next most susceptible cultivar 'Emerald' (0.70 puparia per g). 'Legacy', 'Biloxi', and 'Spring High' were least susceptible to infestation, producing only 0.20-0.25 oriental fruit fly puparia per g of fruit. For Mediterranean fruit fly, 'Blue Crisp' produced 0.50 puparia per g of fruit, whereas 'Sharpblue' produced only 0.03 puparia per g of fruit. Blueberry was a marginal host for melon fly. This information will aid in development of pest management recommendations for blueberry cultivars as planting of low-chill cultivars expands to areas with subtropical and tropical fruit flies. Planting of fruit fly resistant cultivars may result in lower infestation levels and less crop loss.

  20. Population Vulnerability and Disability in Kenya's Tsetse Fly Habitats

    OpenAIRE

    Grady, Sue C.; Messina, Joseph P.; McCord, Paul F.

    2011-01-01

    BACKGROUND: Human African Trypanosomiasis (HAT), also referred to as sleeping sickness, and African Animal Trypanosomaisis (AAT), known as nagana, are highly prevalent parasitic vector-borne diseases in sub-Saharan Africa. Humans acquire trypanosomiasis following the bite of a tsetse fly infected with the protozoa Trypanosoma brucei (T.b.) spp. -i.e., T.b. gambiense in West and Central Africa and T.b. rhodesiense in East and Southern Africa. Over the last decade HAT diagnostic capacity to est...

  1. 4-nitroacetophenone-derived thiosemicarbazones and their copper(II) complexes with significant in vitro anti-trypanosomal activity.

    Science.gov (United States)

    Pérez-Rebolledo, Anayive; Teixeira, Letícia R; Batista, Alzir A; Mangrich, Antonio S; Aguirre, Gabriela; Cerecetto, Hugo; González, Mercedes; Hernández, Paola; Ferreira, Ana M; Speziali, Nivaldo L; Beraldo, Heloisa

    2008-05-01

    N(4)-methyl-4-nitroacetophenone thiosemicarbazone (H4NO(2)Ac4M, 1), N(4),N(4)-dimethyl-4-nitroacetophenone thiosemicarbazone (H4NO(2)Ac4DM, 2) and N(4)-piperidyl-4-nitroacetophenone thiosemicarbazone (H4NO(2)Ac4Pip, 3) and their copper(II) complexes [Cu(4NO(2)Ac4M)(2)] (4), [Cu(4NO(2)Ac4DM)(2)] (5) and [Cu(4NO(2)Ac4Pip)(2)] (6) were tested for their in vitro ability to inhibit the growth of Trypanosoma cruzi epimastigote forms. H4NO(2)Ac4DM (2), [Cu(4NO(2)Ac4M)(2)] (4) and [Cu(4NO(2)Ac4DM)(2)] (5) proved to be as active as the clinical reference drugs nifurtimox and benznidazol. Taking into consideration the serious side effects and the poor efficacy of the reference drugs, as well as the appearance of resistance during treatment, the studied compounds could constitute a new class of anti-trypanosomal drug candidates.

  2. Checklist of American sand flies (Diptera, Psychodidae, Phlebotominae: genera, species, and their distribution

    Directory of Open Access Journals (Sweden)

    Paloma Helena Fernandes Shimabukuro

    2017-03-01

    Full Text Available Phlebotomine sand flies are dipteran insects of medical importance because many species are involved in the transmission of pathogens between human and non-human animals. A total of 530 American species of sand flies is presented in an updated checklist, along with their author(s and year of publication using the classification by Galati (1995, 2003. Distribution by country is also provided.

  3. Discovery and verification of osteopontin and Beta-2-microglobulin as promising markers for staging human African trypanosomiasis.

    Science.gov (United States)

    Tiberti, Natalia; Hainard, Alexandre; Lejon, Veerle; Robin, Xavier; Ngoyi, Dieudonné Mumba; Turck, Natacha; Matovu, Enock; Enyaru, John; Ndung'u, Joseph Mathu; Scherl, Alexander; Dayon, Loïc; Sanchez, Jean-Charles

    2010-12-01

    Human African trypanosomiasis, or sleeping sickness, is a parasitic disease endemic in sub-Saharan Africa, transmitted to humans through the bite of a tsetse fly. The first or hemolymphatic stage of the disease is associated with presence of parasites in the bloodstream, lymphatic system, and body tissues. If patients are left untreated, parasites cross the blood-brain barrier and invade the cerebrospinal fluid and the brain parenchyma, giving rise to the second or meningoencephalitic stage. Stage determination is a crucial step in guiding the choice of treatment, as drugs used for S2 are potentially dangerous. Current staging methods, based on counting white blood cells and demonstrating trypanosomes in cerebrospinal fluid, lack specificity and/or sensitivity. In the present study, we used several proteomic strategies to discover new markers with potential for staging human African trypanosomiasis. Cerebrospinal fluid (CSF) samples were collected from patients infected with Trypanosoma brucei gambiense in the Democratic Republic of Congo. The stage was determined following the guidelines of the national control program. The proteome of the samples was analyzed by two-dimensional gel electrophoresis (n = 9), and by sixplex tandem mass tag (TMT) isobaric labeling (n = 6) quantitative mass spectrometry. Overall, 73 proteins were overexpressed in patients presenting the second stage of the disease. Two of these, osteopontin and β-2-microglobulin, were confirmed to be potential markers for staging human African trypanosomiasis (HAT) by Western blot and ELISA. The two proteins significantly discriminated between S1 and S2 patients with high sensitivity (68% and 78%, respectively) for 100% specificity, and a combination of both improved the sensitivity to 91%. The levels of osteopontin and β-2-microglobulin in CSF of S2 patients (μg/ml range), as well as the fold increased concentration in S2 compared with S1 (3.8 and 5.5 respectively) make the two markers good

  4. The hormonal and behavioral response to the presence and activities of humans in three co-roosting flying fox species (Acerodon jubatus, Pteropus vampyrus and P. hypomelanus ) in Boracay and Mambukal in the Philippines%菲律宾Boracay岛和Mambukal岛三种共栖狐蝠对人类活动的行为和激素反应

    Institute of Scientific and Technical Information of China (English)

    Pascal J.H.VAN DER AA; Renee P.LORICA; Jan KOMDEUR

    2006-01-01

    Many species of large flying foxes are endangered, mainly due to habitat loss and hunting. Although hunting and logging are prohibited in many areas in the Old World Tropics, numbers of flying foxes are still decreasing. The best compromise for the welfare of both local residents and flying foxes in many areas would be ecotourism. However, the effect of human activities on the welfare of flying foxes is unknown and needs to beinvestigated. Using non-invasive methods, stress levels of three species of flying foxes (Pteropus vampyrus, Pteropus hypomelanus and the endangered Acerodon jubatus ) in two tourist areas in the Philippines were investigated, Boracay with little human activity, and Mambukal with intense and large variations in human activities. Fecal samples were collected in the most disturbed area, Mambukal, while the flying foxes were out foraging and concentrations of glucocorticoid metabolites (GCM) were measured.Stress-related as well as other types of behavior, environmental conditions and human activities were measured. The results suggest that flying foxes have habituated to the presence of humans. ( 1 ) We found no overall differences in behaviors between both study sites, which differed significantly in human numbers and activities, and during days with disturbance and days without disturbance. Flying foxes behaved identical in both study sites. (2) No behavior correlated with measured GCM. (3) Despite the large variation in human activities in the study site, we found no effect of human activities on glucocorticoid metabolite concentrations. However, GCM was lower in the center of the colony than in the periphery.(4) Some environmental factors like disturbance and distance from the colony center had an effect on behavioral factors like 'uneasiness' , 'body care' and yawning. If disturbance has no effect on flying fox stress levels, ecotourism would be a good solution to preserve the habitat of endangered flying foxes. However, one has to realize

  5. The Spider and the Fly

    Science.gov (United States)

    Mellinger, Keith E.; Viglione, Raymond

    2012-01-01

    The Spider and the Fly puzzle, originally attributed to the great puzzler Henry Ernest Dudeney, and now over 100 years old, asks for the shortest path between two points on a particular square prism. We explore a generalization, find that the original solution only holds in certain cases, and suggest how this discovery might be used in the…

  6. Electrodialytic treatment of fly ash

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Pedersen, Anne Juul; Kirkelund, Gunvor Marie

    Heavy metals are removed from the fly ashes by an electrodialytic treatment with the aim of up-grading the ashes for reuse in stead of disposal in landfill.A great potential for upgrading of bio- and waste incineration ashes by electrodialytic treatment exists. In the future, the applicability...

  7. DURABILITY OF HARDENED FLY ASH PASTE

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The mechanical properties and durability ( mainly frost-resistance and carbonation resistance ) of fly ash-CaO-CaSO4 .2H2O hardened paste are studied. The relationship among durability of harden ed fly ash paste, the quantity and distribution of hydrates and the initial p aste texture of hardened fly ash paste is presented.

  8. Louse flies on birds of Baja California.

    Science.gov (United States)

    Tella, J L; Rodríguez-Estrella, R; Blanco, G

    2000-01-01

    Louse flies were collected from 401 birds of 32 species captured in autumn of 1996 in Baja California Sur (Mexico). Only one louse fly species (Microlynchia pusilla) was found. It occurred in four of the 164 common ground doves (Columbina passerina) collected. This is a new a host species for this louse fly.

  9. Flies and Campylobacter infection of broiler flocks

    DEFF Research Database (Denmark)

    Hald, Birthe; Skovgård, Henrik; Bang, Dang Duong

    2004-01-01

    A total of 8.2% of flies caught outside a broiler house in Denmark had the potential to transmit Campylobacter jejuni to chickens, and hundreds of flies per day passed through the ventilation system into the broiler house. Our study suggests that flies may be an important source of Campylobacter...

  10. FliO Regulation of FliP in the Formation of the Salmonella enterica Flagellum

    OpenAIRE

    Barker, Clive S.; Meshcheryakova, Irina V.; Kostyukova, Alla S.; Samatey, Fadel A.

    2010-01-01

    The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extrageni...

  11. Investigation of the possibility of binding fly ash particles by elemental sulphur

    Directory of Open Access Journals (Sweden)

    Vidojković V.

    2006-01-01

    Full Text Available Thermal power plants in Serbia use lignite for electrical power production The secondary product of coal combustion is fly ash in the amount of 17%. Fly ash causes the pollution of air, water and soil, and also cause many human, especially lung diseases. Secondary sulphur is a product of crude oil refining. The aim of this study was to investigate the use of sulphur as a bonding material in ultra fine particle agglomeration (smaller than 63 μm in fly ash. The agglomeration should make the ash particles larger and heavy enough to fall without flying fractions. The experiments showed that during the homogenization of the ashes and sulphur from 150 to 170 °C in a reactor with intensive mixing, an amount of 15% sulphur was sufficient to bond particles and cause agglomeration without visible flying fractions.

  12. FliO Regulation of FliP in the Formation of the Salmonella enterica Flagellum

    Science.gov (United States)

    Barker, Clive S.; Meshcheryakova, Irina V.; Kostyukova, Alla S.; Samatey, Fadel A.

    2010-01-01

    The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extragenic bypass mutations in FliP at positions R143H or F190L. Using membrane topology prediction programs, and alkaline phosphatase or GFPuv chimeric protein fusions into the FliO protein, we demonstrated that FliO is bitopic with its N-terminus in the periplasm and C-terminus in the cytoplasm. Truncation analysis of FliO demonstrated that overexpression of FliO43–125 or FliO1–95 was able to rescue motility of the ΔfliO mutant. Further, residue leucine 91 in the cytoplasmic domain was identified to be important for function. Based on secondary structure prediction, the cytoplasmic domain, FliO43–125, should contain beta-structure and alpha-helices. FliO43–125-Ala was purified and studied using circular dichroism spectroscopy; however, this domain was disordered, and its structure was a mixture of beta-sheet and random coil. Coexpression of full-length FliO with FliP increased expression levels of FliP, but coexpression with the cytoplasmic domain of FliO did not enhance FliP expression levels. Overexpression of the cytoplasmic domain of FliO further rescued motility of strains deleted for the fliO gene expressing bypass mutations in FliP. These results suggest FliO maintains FliP stability through transmembrane domain interaction. The results also demonstrate that the cytoplasmic domain of FliO has functionality, and it presumably becomes structured while interacting with its binding partners. PMID:20941389

  13. FliO regulation of FliP in the formation of the Salmonella enterica flagellum.

    Directory of Open Access Journals (Sweden)

    Clive S Barker

    2010-09-01

    Full Text Available The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extragenic bypass mutations in FliP at positions R143H or F190L. Using membrane topology prediction programs, and alkaline phosphatase or GFPuv chimeric protein fusions into the FliO protein, we demonstrated that FliO is bitopic with its N-terminus in the periplasm and C-terminus in the cytoplasm. Truncation analysis of FliO demonstrated that overexpression of FliO₄₃-₁₂₅ or FliO₁-₉₅ was able to rescue motility of the ΔfliO mutant. Further, residue leucine 91 in the cytoplasmic domain was identified to be important for function. Based on secondary structure prediction, the cytoplasmic domain, FliO₄₃-₁₂₅, should contain beta-structure and alpha-helices. FliO₄₃-₁₂₅-Ala was purified and studied using circular dichroism spectroscopy; however, this domain was disordered, and its structure was a mixture of beta-sheet and random coil. Coexpression of full-length FliO with FliP increased expression levels of FliP, but coexpression with the cytoplasmic domain of FliO did not enhance FliP expression levels. Overexpression of the cytoplasmic domain of FliO further rescued motility of strains deleted for the fliO gene expressing bypass mutations in FliP. These results suggest FliO maintains FliP stability through transmembrane domain interaction. The results also demonstrate that the cytoplasmic domain of FliO has functionality, and it presumably becomes structured while interacting with its binding partners.

  14. Bacteria of Phlebotominae Sand Flies Collected in Western Iran

    Directory of Open Access Journals (Sweden)

    Somayeh Rafatbakhsh-Iran

    2015-08-01

    Full Text Available Microorganisms particularly bacteria presenting in insects such as Phlebotominae may play an important role in the epidemiology of human infectious disease. Nowadays, because of vector implications, the routine methods of controlling and spraying have no more beneficial effects on vectors and reservoirs. Little knows about the prevalence and diversity of sand fly bacteria. The main objective of this study was to determine the presence of bacteria of phlebotominae sand flies collected in Hamadan, west of Iran. This information is important in order to development of vector control strategies. The microbial flora of Phlebotomus papatasi and P. sergenti the main vector of Cutaneous Leishmaniasis in the old world, were investigated. We characterized 8 bacteria, including 5 Gram-negative bacteria: Acinetobacter lwoffii, Pseudomonas aeruginosa, Enterobacter cloacae, Edvardsiela sp. and Proteus mirabilis and Gram-positive bacteria: Bacillus subtilis, Staphylococcus saprophyticus and Micrococcus luteus. Our study provides some data on the microbiota diversity of field-collected sand flies for the first time in Hamadan. Our results indicate that there is a range of variation of aerobic bacteria inhabiting sand fly, which possibly reflect the ecological condition of the habitat where the fly breeds. Microbiota is increasingly regarded as an important factor for modulating vector competence in insect vectors. So, mirobiota can be effects on the biology of phlebotominae and their roles in the sandfly-Leishmania interaction. Further experiments are required to clearly delineate the vectorial role of sand flies. Because it is probable that in the future, factors such as environmental changes, migration and urbanization can ease the transmission of leishmaniasis in this area.

  15. Aerodynamics of the Smallest Flying Insects

    CERN Document Server

    Miller, Laura A; Hedrick, Ty; Robinson, Alice; Santhanakrishnan, Arvind; Lowe, Audrey

    2011-01-01

    We present fluid dynamics videos of the flight of some of the smallest insects including the jewel wasp, \\textit{Ampulex compressa}, and thrips, \\textit{Thysanoptera} spp. The fruit fly, \\textit{Drosophila melanogaster}, is large in comparison to these insects. While the fruit fly flies at $Re \\approx 120$, the jewel wasp flies at $Re \\approx 60$, and thrips flies at $Re \\approx 10$. Differences in the general structures of the wakes generated by each species are observed. The differences in the wakes correspond to changes in the ratio of lift forces (vertical component) to drag forces (horizontal component) generated.

  16. A role for flies (Diptera) in the transmission of Campylobacter to broilers?

    Science.gov (United States)

    Royden, A; Wedley, A; Merga, J Y; Rushton, S; Hald, B; Humphrey, T; Williams, N J

    2016-11-01

    Campylobacter is the leading cause of bacterial diarrhoeal disease worldwide, with raw and undercooked poultry meat and products the primary source of infection. Colonization of broiler chicken flocks with Campylobacter has proved difficult to prevent, even with high levels of biosecurity. Dipteran flies are proven carriers of Campylobacter and their ingress into broiler houses may contribute to its transmission to broiler chickens. However, this has not been investigated in the UK. Campylobacter was cultured from 2195 flies collected from four UK broiler farms. Of flies cultured individually, 0·22% [2/902, 95% confidence interval (CI) 0-0·53] were positive by culture for Campylobacter spp. Additionally, 1293 flies were grouped by family and cultured in 127 batches: 4/127 (3·15%, 95% CI 0·11-6·19) from three broiler farms were positive for Campylobacter. Multilocus sequence typing of isolates demonstrated that the flies were carrying broiler-associated sequence types, responsible for human enteric illness. Malaise traps were used to survey the dipteran species diversity on study farms and also revealed up to 612 flies present around broiler-house ventilation inlets over a 2-h period. Therefore, despite the low prevalence of Campylobacter cultured from flies, the risk of transmission by this route may be high, particularly during summer when fly populations are greatest.

  17. Indoor decomposition study in Malaysia with special reference to the scuttle flies (Diptera: Phoridae

    Directory of Open Access Journals (Sweden)

    Raja M. Zuha

    2016-09-01

    Full Text Available Scuttle flies (Diptera: Phoridae are a diversified insect group of forensic importance. Their frequent presence on human corpses indoors and in concealed environments can be the sole indicators to estimate the minimum post mortem interval (PMImin. However, bionomics of scuttle flies on decomposing animal carcasses are rarely documented indoors. The objective of this research is to observe and document the occurrence of scuttle flies on decomposing animal carcass placed inside a portable cabin maintained at room temperature (≈25.0 °C in Bangi, Malaysia. This study was conducted in two rounds for a period of 40-day each and samplings were carried out in different intervals. Adult scuttle flies were aspirated directly from the carcass and preserved in 70% ethanol. Their larvae and pupae were reared until adult stage to facilitate identification. Megaselia scalaris (Loew, Megaselia spiracularis (Schmitz and Dohrniphora cornuta (Bigot were the scuttle flies found on the carcasses with M. scalaris being the earliest and dominant to colonize the body. This cosmopolitan species proved to be the best indicator to estimate PMImin indoor but in the increased presence of other fly species, it might be relegated to a secondary role. The scuttle flies were also found to coexist with other dipterans of forensic importance in an indoor environment, mainly Chrysomya megacephala (Fabricius (Diptera: Calliphoridae. This information expands the knowledge on the bionomics of scuttle flies on decomposing animal remains indoors.

  18. No Evidence of Hendra Virus Infection in the Australian Flying-fox Ectoparasite Genus Cyclopodia.

    Science.gov (United States)

    Vidgen, M E; Edson, D W; van den Hurk, A F; Field, H E; Smith, C S

    2017-05-01

    Hendra virus (HeV) causes potentially fatal respiratory and/or neurological disease in both horses and humans. Although Australian flying-foxes of the genus Pteropus have been identified as reservoir hosts, the precise mechanism of HeV transmission has yet to be elucidated. To date, there has been limited investigation into the role of haematophagous insects as vectors of HeV. This mode of transmission is particularly relevant because Australian flying-foxes host the bat-specific blood-feeding ectoparasites of the genus Cyclopodia (Diptera: Nycteribiidae), also known as bat flies. Using molecular detection methods, we screened for HeV RNA in 183 bat flies collected from flying-foxes inhabiting a roost in Boonah, Queensland, Australia. It was subsequently demonstrated that during the study period, Pteropus alecto in this roost had a HeV RNA prevalence between 2 and 15% (95% CI [1, 6] to [8, 26], respectively). We found no evidence of HeV in any bat flies tested, including 10 bat flies collected from P. alecto in which we detected HeV RNA. Our negative findings are consistent with previous findings and provide additional evidence that bat flies do not play a primary role in HeV transmission. © 2016 Blackwell Verlag GmbH.

  19. Binocular interactions underlying the classic optomotor responses of flying flies

    Directory of Open Access Journals (Sweden)

    Brian J Duistermars

    2012-02-01

    Full Text Available In response to imposed course deviations, the fast optomotor reactions of animals reduce motion blur and facilitate the maintenance of stable body posture. In flies, the monocular front-to-back (progressive and back-to-front (regressive visual motion components generated by horizontal rotation are selectively encoded, respectively, by homo and heterolateral motion sensitive circuits in the third optic ganglion, the lobula plate. To investigate the strength of such inter-ocular interactions and their role in compensatory sensory-motor transformations, we utilize a virtual reality flight simulator to record optomotor reactions by tethered flying flies in response to imposed binocular and monocular visual rotation. With stimulus parameters generating large contrast insensitive optomotor responses to binocular rotation, we find that responses to monocular progressive motion are larger than those to panoramic rotation but contrast sensitive. Conversely, responses to monocular regressive motion are slower than those to rotation and peak at the lowest tested contrast. Together our results suggest that contrast insensitive optomotor responses to binocular rotation result from the dynamic interplay of contralateral inhibitory as well as excitatory circuit interactions and serve to maintain a stable optomotor equilibrium across a range of visual contrasts.

  20. NUP-1 Is a large coiled-coil nucleoskeletal protein in trypanosomes with lamin-like functions.

    Directory of Open Access Journals (Sweden)

    Kelly N DuBois

    Full Text Available A unifying feature of eukaryotic nuclear organization is genome segregation into transcriptionally active euchromatin and transcriptionally repressed heterochromatin. In metazoa, lamin proteins preserve nuclear integrity and higher order heterochromatin organization at the nuclear periphery, but no non-metazoan lamin orthologues have been identified, despite the likely presence of nucleoskeletal elements in many lineages. This suggests a metazoan-specific origin for lamins, and therefore that distinct protein elements must compose the nucleoskeleton in other lineages. The trypanosomatids are highly divergent organisms and possess well-documented but remarkably distinct mechanisms for control of gene expression, including polycistronic transcription and trans-splicing. NUP-1 is a large protein localizing to the nuclear periphery of Trypanosoma brucei and a candidate nucleoskeletal component. We sought to determine if NUP-1 mediates heterochromatin organization and gene regulation at the nuclear periphery by examining the influence of NUP-1 knockdown on morphology, chromatin positioning, and transcription. We demonstrate that NUP-1 is essential and part of a stable network at the inner face of the trypanosome nuclear envelope, since knockdown cells have abnormally shaped nuclei with compromised structural integrity. NUP-1 knockdown also disrupts organization of nuclear pore complexes and chromosomes. Most significantly, we find that NUP-1 is required to maintain the silenced state of developmentally regulated genes at the nuclear periphery; NUP-1 knockdown results in highly specific mis-regulation of telomere-proximal silenced variant surface glycoprotein (VSG expression sites and procyclin loci, indicating a disruption to normal chromatin organization essential to life-cycle progression. Further, NUP-1 depletion leads to increased VSG switching and therefore appears to have a role in control of antigenic variation. Thus, analogous to vertebrate

  1. Trypanosomes and haemosporidia in the buzzard (Buteo buteo) and sparrowhawk (Accipiter nisus): factors affecting the prevalence of parasites.

    Science.gov (United States)

    Svobodová, Milena; Weidinger, Karel; Peške, Lubomír; Volf, Petr; Votýpka, Jan; Voříšek, Petr

    2015-02-01

    The prevalences of heteroxenous parasites are influenced by the interplay of three main actors: hosts, vectors, and the parasites themselves. We studied blood protists in the nesting populations of raptors in two different areas of the Czech Republic. Altogether, 788 nestlings and 258 adult Eurasian sparrowhawks (Accipiter nisus) and 321 nestlings and 86 adult common buzzards (Buteo buteo) were screened for parasites by the microscopic examination of blood smears and by cultivation. We examined the role of shared vectors and parasite phylogenetic relationships on the occurrence of parasites. In different years and hosts, trypanosome prevalence ranged between 1.9 and 87.2 %, that of Leucocytozoon between 1.9 and 100 %, and Haemoproteus between 0 and 72.7 %. Coinfections with Leucocytozoon and Trypanosoma, phylogenetically distant parasites but both transmitted by blackflies (Simuliidae), were more frequent than coinfections with Leucocytozoon and Haemoproteus, phylogenetically closely related parasites transmitted by different vectors (blackflies and biting midges (Ceratopogonidae), respectively). For example, 16.6 % buzzard nestlings were coinfected with Trypanosoma and Leucocytozoon, while only 4.8 % with Leucocytozoon and Haemoproteus and 0.3 % with Trypanosoma and Haemoproteus. Nestlings in the same nest tended to have the same infection status. Furthermore, prevalence increased with the age of nestlings and with Julian date, while brood size had only a weak negative/positive effect on prevalence at the individual/brood level. Prevalences in a particular avian host species also varied between study sites and years. All these factors should thus be considered while comparing prevalences from different studies, the impact of vectors being the most important. We conclude that phylogenetically unrelated parasites that share the same vectors tend to have similar distributions within the host populations of two different raptor species.

  2. "Fly me to the moon"

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ China's first lunar probe Chang'e-I, named after a mythical Chinese goddess who, according to legend, made her home on the moon, blasted off on 24 October from the Xichang Satellite Launch Center in the southwestern province of Sichuan. In addition to making the dream cherished by Chinese people to fly to the moon come true, it is the first step into China's ambitious threestage moon mission, marking a new milestone in the country's space exploration history.

  3. Notes on flying and dying.

    Science.gov (United States)

    Meyer, B C

    1983-07-01

    Focused on selected details in the lives and creative works of Samuel Johnson, Edgar Allan Poe, and Houdini, this paper explores a seeming antinomy between claustrophobic annihilation and aviation. At first glance the latter appears as an antidote to the threat of entrapment and death. On a deeper level the distinction fades as the impression arises that in the examples cited, flying may represent an unconscious expression of a wish for death and ultimate reunion.

  4. Genome of the house fly, Musca domestica L., a global vector of diseases with adaptations to a septic environment

    NARCIS (Netherlands)

    Scott, Jeffrey G; Warren, Wesley C; Beukeboom, Leo W; Bopp, Daniel; Clark, Andrew G; Giers, Sarah D; Hediger, Monika; Jones, Andrew K; Kasai, Shinji; Leichter, Cheryl A; Li, Ming; Meisel, Richard P; Minx, Patrick; Murphy, Terence D; Nelson, David R; Reid, William R; Rinkevich, Frank D; Robertson, Hugh M; Sackton, Timothy B; Sattelle, David B; Thibaud-Nissen, Francoise; Tomlinson, Chad; Jacobus Mgn Van De Zande, Louis; Walden, Kimberly; Wilson, Richard K; Liu, Nannan

    2014-01-01

    BACKGROUND: Adult house flies, Musca domestica L., are mechanical vectors of more than 100 devastating diseases that have severe consequences for human and animal health. House fly larvae play a vital role as decomposers of animal wastes, and thus live in intimate association with many animal pathog

  5. Recombinant acetylcholinesterase 1 of the sand fly Phlebotomus papatasi (Scopoli): expression, biochemical properties, and insensitivity to organophosphate inhibition

    Science.gov (United States)

    Phlebotomine sand flies are small hematophagous vectors of human and zoonotic leishmaniases present throughout tropical and subtropical areas of the world. These flies present serious problems for military operations and resident populations in the Middle East and other areas where they are endemic....

  6. Dose-dependent fate of GFP-expressing Escherichia coli in the alimentary canal of adult house flies.

    Science.gov (United States)

    Kumar, N H V; Nayduch, D

    2016-06-01

    The adult house fly Musca domestica (L.) (Diptera: Muscidae) can disseminate bacteria from microbe-rich substrates to areas in which humans and domesticated animals reside. Because bacterial abundance fluctuates widely across substrates, flies encounter and ingest varying amounts of bacteria. This study investigated the dose-dependent survival of bacteria in house flies. Flies were fed four different 'doses' of green fluorescent protein (GFP)-expressing Escherichia coli (GFP E. coli) (very low, low, medium, high) and survival was determined at 1, 4, 10 and 22 h post-ingestion by culture and epifluorescent microscopy. Over 22 h, the decline in GFP E. coli was significant in all treatments (P house flies, may exist and is likely to be immune-mediated. Understanding dose-dependent bacterial survival in flies can help in predicting bacteria transmission potential.

  7. A zebrafish transgenic model of Ewing’s sarcoma reveals conserved mediators of EWS-FLI1 tumorigenesis

    Directory of Open Access Journals (Sweden)

    Stefanie W. Leacock

    2012-01-01

    Ewing’s sarcoma, a malignant bone tumor of children and young adults, is a member of the small-round-blue-cell tumor family. Ewing’s sarcoma family tumors (ESFTs, which include peripheral primitive neuroectodermal tumors (PNETs, are characterized by chromosomal translocations that generate fusions between the EWS gene and ETS-family transcription factors, most commonly FLI1. The EWS-FLI1 fusion oncoprotein represents an attractive therapeutic target for treatment of Ewing’s sarcoma. The cell of origin of ESFT and the molecular mechanisms by which EWS-FLI1 mediates tumorigenesis remain unknown, and few animal models of Ewing’s sarcoma exist. Here, we report the use of zebrafish as a vertebrate model of EWS-FLI1 function and tumorigenesis. Mosaic expression of the human EWS-FLI1 fusion protein in zebrafish caused the development of tumors with histology strongly resembling that of human Ewing’s sarcoma. The incidence of tumors increased in a p53 mutant background, suggesting that the p53 pathway suppresses EWS-FLI1-driven tumorigenesis. Gene expression profiling of the zebrafish tumors defined a set of genes that might be regulated by EWS-FLI1, including the zebrafish ortholog of a crucial EWS-FLI1 target gene in humans. Stable zebrafish transgenic lines expressing EWS-FLI1 under the control of the heat-shock promoter exhibit altered embryonic development and defective convergence and extension, suggesting that EWS-FLI1 interacts with conserved developmental pathways. These results indicate that functional targets of EWS-FLI1 that mediate tumorigenesis are conserved from zebrafish to human and provide a novel context in which to study the function of this fusion oncogene.

  8. Zoonotic trypanosomes in South East Asia: Attempts to control Trypanosoma lewisi using veterinary drugs.

    Science.gov (United States)

    Desquesnes, Marc; Yangtara, Sarawut; Kunphukhieo, Pawinee; Chalermwong, Piangjai; Jittapalapong, Sathaporn; Herder, Stéphane

    2016-06-01

    A growing number of atypical human infections due to the livestock parasite Trypanosoma evansi, or to the rat parasite Trypanosoma lewisi, are reported in humans in Asia. In some cases, clinical evolutions request treatments, however, so far, there were very few attempts to control T. lewisi using trypanocidal drugs. In a study published elsewhere, the efficacy of human trypanocides is evaluated in laboratory rats, and it concludes that none of them is able to cure rats experimentally infected with T. lewisi. Control of T. lewisi in rat would be a step for identification of drugs against this parasite. In the present study, 4 veterinary drugs: diminazene aceturate, isometamidium chloride, melarsomine hydrochloride and quinapyramine sulfate and chloride, were evaluated at low and high doses, in intra-muscular injections to normal rats experimentally infected with a stock of T. lewisi from Thailand. None of these treatments being efficient, a trial was also made using melarsomine hydrochloride in T. evansi infected rats and in mixed T. lewisi and T. evansi infected rats, in order to demonstrate the efficacy of the drugs under the present protocol. T. evansi was cleared from the rat's blood the day after the treatment, while, T. lewisi remained unaffected until the end of the experiment. These observations clearly demonstrated the efficacy of melarsomine hydrochloride against T. evansi and its inefficacy against T. lewisi. In conclusion none of the veterinary drugs was efficient against this stock of T. lewisi. Other protocols using higher doses or other drugs and T. lewisi stocks should be investigated in further studies. The control of T. lewisi infection in Wistar rats, using veterinary trypanocidal drugs, remains so far unsuccessful.

  9. Identifying glass compositions in fly ash

    Directory of Open Access Journals (Sweden)

    Katherine eAughenbaugh

    2016-01-01

    Full Text Available In this study, four Class F fly ashes were studied with a scanning electron microscope; the glassy phases were identified and their compositions quantified using point compositional analysis with k-means clustering and multispectral image analysis. The results showed that while the bulk oxide contents of the fly ashes were different, the four fly ashes had somewhat similar glassy phase compositions. Aluminosilicate glasses (AS, calcium aluminosilicate glasses (CAS, a mixed glass, and, in one case, a high iron glass were identified in the fly ashes. Quartz and iron crystalline phases were identified in each fly ash as well. The compositions of the three main glasses identified, AS, CAS, and mixed glass, were relatively similar in each ash. The amounts of each glass were varied by fly ash, with the highest calcium fly ash containing the most of calcium-containing glass. Some of the glasses were identified as intermixed in individual particles, particularly the calcium-containing glasses. Finally, the smallest particles in the fly ashes, with the most surface area available to react in alkaline solution, such as when mixed with portland cement or in alkali-activated fly ash, were not different in composition than the large particles, with each of the glasses represented. The method used in the study may be applied to a fly ash of interest for use as a cementing material in order to understand its potential for reactivity.

  10. Sarcophaga (Liosarcophaga) dux (Diptera: Sarcophagidae): A flesh fly species of medical importance.

    Science.gov (United States)

    Sukontason, Kabkaew L; Sanit, Sangob; Klong-Klaew, Tunwadee; Tomberlin, Jeffery K; Sukontason, Kom

    2014-04-01

    Although tropical climate of Thailand is suitably endowed with biodiversity of insects, flies of medical importance is not well investigated. Using information from literature search, fly survey approach and specialist's experience, we review database of Sarcophaga (Liosarcophaga) dux Thomson (Diptera: Sarcophagidae), one of the priorities flesh fly species of medical importance in Thailand. This review deals with morphology, bionomics and medical involvement. Important morphological characteristics of egg, larva, puparia and adult were highlighted with illustration and/or micrographs. Search pertaining to molecular analysis used for fly identification and developmental rate of larvae were included. Medical involvement of larvae was not only myiasis-producing agent in humans and animals, but associated with human death investigations. This information will enable us to accurate identify this species and to emphasis the increase medically important scene in Thailand.

  11. The interplay between obesity and cancer: a fly view

    Science.gov (United States)

    2016-01-01

    ABSTRACT Accumulating epidemiological evidence indicates a strong clinical association between obesity and an increased risk of cancer. The global pandemic of obesity indicates a public health trend towards a substantial increase in cancer incidence and mortality. However, the mechanisms that link obesity to cancer remain incompletely understood. The fruit fly Drosophila melanogaster has been increasingly used to model an expanding spectrum of human diseases. Fly models provide a genetically simpler system that is ideal for use as a first step towards dissecting disease interactions. Recently, the combining of fly models of diet-induced obesity with models of cancer has provided a novel model system in which to study the biological mechanisms that underlie the connections between obesity and cancer. In this Review, I summarize recent advances, made using Drosophila, in our understanding of the interplay between diet, obesity, insulin resistance and cancer. I also discuss how the biological mechanisms and therapeutic targets that have been identified in fly studies could be utilized to develop preventative interventions and treatment strategies for obesity-associated cancers. PMID:27604692

  12. Testing candidate genes for attention-deficit/hyperactivity disorder in fruit flies using a high throughput assay for complex behavior

    DEFF Research Database (Denmark)

    Rohde, Palle Duun; Madsen, Lisbeth Strøm; Arvidson, Sandra Marie Neumann

    2016-01-01

    Fruit flies are important model organisms for functional testing of candidate genes in multiple disciplines, including the study of human diseases. Here we use a high-throughput locomotor activity assay to test the response on activity behavior of gene disruption in Drosophila melanogaster. The aim...... was to investigate the impact of disruption of 14 candidate genes for human attention-deficit/hyperactivity disorder (ADHD) on fly behavior. By obtaining a range of correlated measures describing the space of variables for behavioral activity we show, that some mutants display similar phenotypic responses...... in fruit flies. Results provide additional support for the investigated genes being risk candidate genes for ADHD in humans....

  13. Flying Ad-Hoc Networks: Routing Protocols, Mobility Models, Issues

    OpenAIRE

    Muneer Bani Yassein; “Nour Alhuda” Damer

    2016-01-01

    Flying Ad-Hoc Networks (FANETs) is a group of Unmanned Air Vehicles (UAVs) which completed their work without human intervention. There are some problems in this kind of networks: the first one is the communication between (UAVs). Various routing protocols introduced classified into three categories, static, proactive, reactive routing protocols in order to solve this problem. The second problem is the network design, which depends on the network mobility, in which is the process of cooperati...

  14. Transmission of pathogens by Stomoxys flies (Diptera, Muscidae): a review

    OpenAIRE

    Baldacchino, Frédéric; Muenworn, Vithee; Desquesnes, Marc; Desoli, Florian; Charoenviriyaphap, Theeraphap; Duvallet, Gérard

    2013-01-01

    Stomoxys flies are mechanical vectors of pathogens present in the blood and skin of their animal hosts, especially livestock, but occasionally humans. In livestock, their direct effects are disturbance, skin lesions, reduction of food intake, stress, blood loss, and a global immunosuppressive effect. They also induce the gathering of animals for mutual protection; meanwhile they favor development of pathogens in the hosts and their transmission. Their indirect effect is the mechanical transmi...

  15. Alkaloids Induce Programmed Cell Death in Bloodstream Forms of Trypanosomes (Trypanosoma b. brucei

    Directory of Open Access Journals (Sweden)

    Michael Wink

    2008-10-01

    Full Text Available The potential induction of a programmed cell death (PCD in Trypanosoma b. brucei by 55 alkaloids of the quinoline, quinolizidine, isoquinoline, indole, terpene, tropane, steroid, and piperidine type was studied by measuring DNA fragmentation and changes in mitochondrial membrane potential. For comparison, the induction of apoptosis by the same alkaloids in human leukemia cells (Jurkat APO-S was tested. Several alkaloids of the isoquinoline, quinoline, indole and steroidal type (berberine, chelerythrine, emetine, sanguinarine, quinine, ajmalicine, ergotamine, harmine, vinblastine, vincristine, colchicine, chaconine, demissidine and veratridine induced programmed cell death, whereas quinolizidine, tropane, terpene and piperidine alkaloids were mostly inactive. Effective PCD induction (EC50 below 10 µM was caused in T. brucei by chelerythrine, emetine, sanguinarine, and chaconine. The active alkaloids can be characterized by their general property to inhibit protein biosynthesis, to intercalate DNA, to disturb membrane fluidity or to inhibit microtubule formation.

  16. Choice of optimal biocide combination to control flies (Diptera: Muscidae

    Directory of Open Access Journals (Sweden)

    Mihaela Kavran

    2015-05-01

    Full Text Available Introduction. Flies – by feeding on decaying matter, human waste and food – have been implicated in the spread of numerous animal and human diseases. Excessive fly populations are generally associated with livestock units and domestic waste due to decaying organic matter. A large number of flies cause extreme disturbance in the behavior of the host, resulting in skin irritation, lesions, wounds, and secondary infections are likely to appear. Objective. The aim of this study was to evaluate the effects of combined applications of larvicide (cyromazine and adulticides (acetamiprid in formulation with pheromone and thiamethoxam on the suppression of fly populations. Materials and methods. The study was conducted on a pig farm. The piglet farms are one of the most favorable places for fly breeding. Three units were used for biocide applications and a fourth unit as the control where biocides were not applied. The monitoring of pre- and post-treatment of adult fly populations was carried out by glued cardboards. The cards were hung on metal rods above piglet’s cage. This monitoring method served as a parameter for the estimation of biological effectiveness. Results. The highest degree of fly control (88.4% mortality 8 days after treatment was achieved when a combination of cyromazine and thiamethoxam was used. A biocide based on sex pheromone (Z-9-tricosene + acetamiprid was the most effective on flies 3 days after biocide application, with a mortality rate of 69.1 %. Thiamethoxam achieved the highest reduction of flies 6 days after treatment, with 78.19% obtained mortality. Conclusion. Biological efficacy of the applied biocides in combination ciromazine + thiamethoxam and thiamethoxam alone was justified.

  17. Anti-trypanosomal activity of pentacyclic triterpenes isolated from Austroplenckia populnea (Celastraceae Atividade anti-tripanosomicida de triterpenes pentacíclicos isolados de Austroplenckia populnea (Celastraceae

    Directory of Open Access Journals (Sweden)

    Lucienir Pains DUARTE

    2002-04-01

    Full Text Available Four pentacyclic triterpenes isolated from Austroplenckia populnea and four compounds of known anti T. cruzi or anti-malarial activity were tested. Of those triterpenes tested 20alpha-hydroxy-tingenone showed high activity, epikatonic acid was less active, while populnilic and populninic acids were inactive against the trypanosome of the subgenus Schizotrypanum tested. Benzonidazole, nifurtimox, ketoconazole and primaquine presented a remarkable dose-dependent inhibitory effect reaching practically to a total growth inhibition of the parasite at the end of incubation time. The trypanosome tested appear to be a suitable model for preliminary screen for anti T. (S. cruzi compounds.Foram testados quatro triterpenos pentacíclicos isolados de Austroplenckia populnea e quatro compostos de conhecida atividade anti-T. cruzi ou anti-malárica. Dos triterpenos testados 20alfa-hidroxi-tingenona mostrou atividade elevada, ácido epicatônico foi menos ativo, enquanto ácido populnílico e populnínico foram inativos contra o tripanossoma do subgênero Schizotrypanum testado. Benzonidazole, nifurtimox, cetoconazole e primaquina apresentaram efeito inibitório dose-dependente atingindo praticamente a inibição total do crescimento do parasita no final do tempo de incubação. O tripanossoma testado mostrou ser um modelo adequado para uma seleção preliminar de compostos anti. T. (S. cruzi.

  18. Ultrasonic vocalizations emitted by flying squirrels.

    Directory of Open Access Journals (Sweden)

    Meghan N Murrant

    Full Text Available Anecdotal reports of ultrasound use by flying squirrels have existed for decades, yet there has been little detailed analysis of their vocalizations. Here we demonstrate that two species of flying squirrel emit ultrasonic vocalizations. We recorded vocalizations from northern (Glaucomys sabrinus and southern (G. volans flying squirrels calling in both the laboratory and at a field site in central Ontario, Canada. We demonstrate that flying squirrels produce ultrasonic emissions through recorded bursts of broadband noise and time-frequency structured frequency modulated (FM vocalizations, some of which were purely ultrasonic. Squirrels emitted three types of ultrasonic calls in laboratory recordings and one type in the field. The variety of signals that were recorded suggest that flying squirrels may use ultrasonic vocalizations to transfer information. Thus, vocalizations may be an important, although still poorly understood, aspect of flying squirrel social biology.

  19. Possibilities of utilizing power plant fly ashes

    Directory of Open Access Journals (Sweden)

    Mezencevová Andrea

    2003-09-01

    Full Text Available The burning of fossil fuels in industrial power stations plays a significant role in the production of thermal and electrical energy. Modern thermal power plants are producing large amounts of solid waste, mainly fly ashes. The disposal of power plant waste is a large environmental problem at the present time. In this paper, possibilities of utilization of power plant fly ashes in industry, especially in civil engineering, are presented. The fly ash is a heterogeneous material with various physical, chemical and mineralogical properties, depending on the mineralogical composition of burned coal and on the used combustion technology. The utilization of fly ashes is determined of their properties. The fineness, specific surface area, particle shape, density, hardness, freeze-thaw resistance, etc. are decisive. The building trade is a branch of industry, which employs fly ash in large quantities for several decades.The best utilization of fluid fly ashes is mainly in the production of cement and concrete, due to the excellent pozzolanic and cementitious properties of this waste. In the concrete processing, the fly ash is utilized as a replacement of the fine aggregate (fine filler or a partial replacement for cement (active admixture. In addition to economic and ecological benefits, the use of fly ash in concrete improves its workability and durability, increases compressive and flexural strength, reduces segregation, bleeding, shrinkage, heat evolution and permeability and enhances sulfate resistance of concrete.The aim of current research is to search for new technologies for the fly ash utilization. The very interesting are biotechnological methods to recovery useful components of fly ashes and unconventional methods of modification of fly ash properties such as hydrothermal zeolitization and mechanochemical modification of its properties. Mechanochemistry deals with physico - chemical transformations and chemical reactions of solids induced by

  20. Revised irradiation doses to control melon fly, Mediterranean fruit fly, and oriental fruit fly (Diptera: Tephritidae) and a generic dose for tephritid fruit flies.

    Science.gov (United States)

    Follett, Peter A; Armstrong, John W

    2004-08-01

    Currently approved irradiation quarantine treatment doses for Bactrocera cucurbitae (Coquillet), melon fly; Ceratitis capitata (Wiedemann), Mediterranean fruit fly; and Bactrocera dorsalis (Hendel), oriental fruit fly, infesting fruits and vegetables for export from Hawaii to the continental United States are 210, 225, and 250 Gy, respectively. Irradiation studies were initiated to determine whether these doses could be reduced to lower treatment costs, minimize any adverse effects on quality, and support a proposed generic irradiation dose of 150 Gy for fruit flies. Dose-response tests were conducted with late third instars of wild and laboratory strains of the three fruit fly species, both in diet and in fruit. After x-ray irradiation treatment, data were taken on adult emergence, and adult female fecundity and fertility. Melon fly was the most tolerant of the three species to irradiation, and oriental fruit fly was more tolerant than Mediterranean fruit fly. Laboratory and wild strains of each species were equally tolerant of irradiation, and larvae were more tolerant when irradiated in fruit compared with artificial diet. An irradiation dose of 150 Gy applied to 93,666 melon fly late third instars in papayas resulted in no survival to the adult stage, indicating that this dose is sufficient to provide quarantine security. Irradiation doses of 100 and 125 Gy applied to 31,920 Mediterranean fruit fly and 55,743 oriental fruit fly late third instars, respectively, also resulted in no survival to the adult stage. Results support a proposed generic irradiation quarantine treatment dose of 150 Gy for all tephritid fruit flies.

  1. In situ structure of trypanosomal ATP synthase dimer reveals a unique arrangement of catalytic subunits

    Science.gov (United States)

    Mühleip, Alexander W.; Dewar, Caroline E.; Schnaufer, Achim; Kühlbrandt, Werner; Davies, Karen M.

    2017-01-01

    We used electron cryotomography and subtomogram averaging to determine the in situ structures of mitochondrial ATP synthase dimers from two organisms belonging to the phylum euglenozoa: Trypanosoma brucei, a lethal human parasite, and Euglena gracilis, a photosynthetic protist. At a resolution of 32.5 Å and 27.5 Å, respectively, the two structures clearly exhibit a noncanonical F1 head, in which the catalytic (αβ)3 assembly forms a triangular pyramid rather than the pseudo-sixfold ring arrangement typical of all other ATP synthases investigated so far. Fitting of known X-ray structures reveals that this unusual geometry results from a phylum-specific cleavage of the α subunit, in which the C-terminal αC fragments are displaced by ∼20 Å and rotated by ∼30° from their expected positions. In this location, the αC fragment is unable to form the conserved catalytic interface that was thought to be essential for ATP synthesis, and cannot convert γ-subunit rotation into the conformational changes implicit in rotary catalysis. The new arrangement of catalytic subunits suggests that the mechanism of ATP generation by rotary ATPases is less strictly conserved than has been generally assumed. The ATP synthases of these organisms present a unique model system for discerning the individual contributions of the α and β subunits to the fundamental process of ATP synthesis. PMID:28096380

  2. In Silico Investigation of Flavonoids as Potential Trypanosomal Nucleoside Hydrolase Inhibitors

    Directory of Open Access Journals (Sweden)

    Christina Hung Hung Ha

    2015-01-01

    Full Text Available Human African Trypanosomiasis is endemic to 37 countries of sub-Saharan Africa. It is caused by two related species of Trypanosoma brucei. Current therapies suffer from resistance and public accessibility of expensive medicines. Finding safer and effective therapies of natural origin is being extensively explored worldwide. Pentamidine is the only available therapy for inhibiting the P2 adenosine transporter involved in the purine salvage pathway of the trypanosomatids. The objective of the present study is to use computational studies for the investigation of the probable trypanocidal mechanism of flavonoids. Docking experiments were carried out on eight flavonoids of varying level of hydroxylation, namely, flavone, 5-hydroxyflavone, 7-hydroxyflavone, chrysin, apigenin, kaempferol, fisetin, and quercetin. Using AutoDock 4.2, these compounds were tested for their affinity towards inosine-adenosine-guanosine nucleoside hydrolase and the inosine-guanosine nucleoside hydrolase, the major enzymes of the purine salvage pathway. Our results showed that all of the eight tested flavonoids showed high affinities for both hydrolases (lowest free binding energy ranging from −10.23 to −7.14 kcal/mol. These compounds, especially the hydroxylated derivatives, could be further studied as potential inhibitors of the nucleoside hydrolases.

  3. Flying qualities criteria and flight control design

    Science.gov (United States)

    Berry, D. T.

    1981-01-01

    Despite the application of sophisticated design methodology, newly introduced aircraft continue to suffer from basic flying qualities deficiencies. Two recent meetings, the DOD/NASA Workshop on Highly Augmented Aircraft Criteria and the NASA Dryden Flight Research Center/Air Force Flight Test Center/AIAA Pilot Induced Oscillation Workshop, addressed this problem. An overview of these meetings is provided from the point of view of the relationship between flying qualities criteria and flight control system design. Among the items discussed are flying qualities criteria development, the role of simulation, and communication between flying qualities specialists and control system designers.

  4. What the fly's nose tells the fly's brain.

    Science.gov (United States)

    Stevens, Charles F

    2015-07-28

    The fly olfactory system has a three-layer architecture: The fly's olfactory receptor neurons send odor information to the first layer (the encoder) where this information is formatted as combinatorial odor code, one which is maximally informative, with the most informative neurons firing fastest. This first layer then sends the encoded odor information to the second layer (decoder), which consists of about 2,000 neurons that receive the odor information and "break" the code. For each odor, the amplitude of the synaptic odor input to the 2,000 second-layer neurons is approximately normally distributed across the population, which means that only a very small fraction of neurons receive a large input. Each odor, however, activates its own population of large-input neurons and so a small subset of the 2,000 neurons serves as a unique tag for the odor. Strong inhibition prevents most of the second-stage neurons from firing spikes, and therefore spikes from only the small population of large-input neurons is relayed to the third stage. This selected population provides the third stage (the user) with an odor label that can be used to direct behavior based on what odor is present.

  5. Characteristics of spanish fly ashes

    Directory of Open Access Journals (Sweden)

    de Luxán, M. P.

    1988-03-01

    Full Text Available The purpose of this study is the characterization of fly ashes produced by Spanish thermoelectric power plants, according to sampling taken in 1981 and 1982. The study takes in the following characteristics: physical characteristics (size distribution of particles, ...; chemical ones (chemical analysis...; and mineralogical ones (application of instrumental techniques of X-ray diffraction and infrared absorption spectroscopy. From a general point of view, it can be said that the samples of Spanish fly ashes are similar to those produced in other countries. The results obtained are a contribution to the knowledge of Spanish fly ashes and form part of the antecedents of investigations carried out in subsequent years.

    Este trabajo tiene por objeto la caracterización de las cenizas volantes producidas en las Centrales Termoeléctricas españolas, según un muestreo realizado entre 1981 y 1982. El estudio comprende las siguientes características: físicas (distribución del tamaño de partículas,...; químicas (análisis químico, …; y mineralógicas (aplicación de las técnicas instrumentales de difracción de rayos X y espectroscopía de absorción infrarroja. Desde un punto de vista general, se puede afirmar que las muestras de ceniza volante estudiadas son semejantes a las producidas en otros países. Los resultados obtenidos son una aportación al conocimiento de las cenizas volantes españolas y forman parte de los antecedentes de las investigaciones llevadas a cabo en años posteriores.

  6. Detailed interrogation of trypanosome cell biology via differential organelle staining and automated image analysis

    Directory of Open Access Journals (Sweden)

    Wheeler Richard J

    2012-01-01

    Full Text Available Abstract Background Many trypanosomatid protozoa are important human or animal pathogens. The well defined morphology and precisely choreographed division of trypanosomatid cells makes morphological analysis a powerful tool for analyzing the effect of mutations, chemical insults and changes between lifecycle stages. High-throughput image analysis of micrographs has the potential to accelerate collection of quantitative morphological data. Trypanosomatid cells have two large DNA-containing organelles, the kinetoplast (mitochondrial DNA and nucleus, which provide useful markers for morphometric analysis; however they need to be accurately identified and often lie in close proximity. This presents a technical challenge. Accurate identification and quantitation of the DNA content of these organelles is a central requirement of any automated analysis method. Results We have developed a technique based on double staining of the DNA with a minor groove binding (4'', 6-diamidino-2-phenylindole (DAPI and a base pair intercalating (propidium iodide (PI or SYBR green fluorescent stain and color deconvolution. This allows the identification of kinetoplast and nuclear DNA in the micrograph based on whether the organelle has DNA with a more A-T or G-C rich composition. Following unambiguous identification of the kinetoplasts and nuclei the resulting images are amenable to quantitative automated analysis of kinetoplast and nucleus number and DNA content. On this foundation we have developed a demonstrative analysis tool capable of measuring kinetoplast and nucleus DNA content, size and position and cell body shape, length and width automatically. Conclusions Our approach to DNA staining and automated quantitative analysis of trypanosomatid morphology accelerated analysis of trypanosomatid protozoa. We have validated this approach using Leishmania mexicana, Crithidia fasciculata and wild-type and mutant Trypanosoma brucei. Automated analysis of T. brucei

  7. Use of chiral cell shape to ensure highly directional swimming in trypanosomes.

    Science.gov (United States)

    Wheeler, Richard John

    2017-01-01

    Swimming cells typically move along a helical path or undergo longitudinal rotation as they swim, arising from chiral asymmetry in hydrodynamic drag or propulsion bending the swimming path into a helix. Helical paths are beneficial for some forms of chemotaxis, but why asymmetric shape is so prevalent when a symmetric shape would also allow highly directional swimming is unclear. Here, I analyse the swimming of the insect life cycle stages of two human parasites; Trypanosoma brucei and Leishmania mexicana. This showed quantitatively how chirality in T. brucei cell shape confers highly directional swimming. High speed videomicrographs showed that T. brucei, L. mexicana and a T. brucei RNAi morphology mutant have a range of shape asymmetries, from wild-type T. brucei (highly chiral) to L. mexicana (near-axial symmetry). The chiral cells underwent longitudinal rotation while swimming, with more rapid longitudinal rotation correlating with swimming path directionality. Simulation indicated hydrodynamic drag on the chiral cell shape caused rotation, and the predicted geometry of the resulting swimming path matched the directionality of the observed swimming paths. This simulation of swimming path geometry showed that highly chiral cell shape is a robust mechanism through which microscale swimmers can achieve highly directional swimming at low Reynolds number. It is insensitive to random variation in shape or propulsion (biological noise). Highly symmetric cell shape can give highly directional swimming but is at risk of giving futile circular swimming paths in the presence of biological noise. This suggests the chiral T. brucei cell shape (associated with the lateral attachment of the flagellum) may be an adaptation associated with the bloodstream-inhabiting lifestyle of this parasite for robust highly directional swimming. It also provides a plausible general explanation for why swimming cells tend to have strong asymmetries in cell shape or propulsion.

  8. The impacts of a fliD mutation on the biofilm formation of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    Panan Ratthawongjirakul; Vorraruthai Thongkerd; Wanpen Chaicumpa

    2016-01-01

    Objective: To investigate the impact of the fliD gene on the biofilm formation of Hel-icobacter pylori (H. pylori). Methods: H. pylori fliD mutant was constructed using inverse PCR mutagenesis. The mobility of the bacteria and its adhesion ability to human epithelial cells were assessed using a motility assay and a fluorescein isothiocyanate staining adhesion assay, respec-tively. The formation of biofilm was evaluated using a pellicle assay and a crystal violet staining assay. The cyto-architecture of the biofilm was documented with scanning electron microscopy. Results: It was found that there was no significant difference in the levels of bacterial adhesion and the biofilm formation between the wild-type ATCC 43504 and the fliD mutant. Apart from a poor motility, the fliD mutant had a slightly delayed formation of its biofilm and an incomplete cyto-architecture of its biofilm. The bacterial cells residing in the biofilm of the fliD mutant showed a loose accumulation with less apparent cross-linking fibrils. Most of the mutant cells had truncated flagella. Conclusions: This study provides the preliminary evidences that fliD potentially regu-lates biofilm formation and is required for the motility of H. pylori. Further studies need to be performed in order to develop fliD as a novel target for vaccine or antimicrobial agent in future.

  9. Recrudescent infection supports Hendra virus persistence in Australian flying-fox populations.

    Directory of Open Access Journals (Sweden)

    Hsiao-Hsuan Wang

    Full Text Available Zoonoses from wildlife threaten global public health. Hendra virus is one of several zoonotic viral diseases that have recently emerged from Pteropus species fruit-bats (flying-foxes. Most hypotheses regarding persistence of Hendra virus within flying-fox populations emphasize horizontal transmission within local populations (colonies via urine and other secretions, and transmission among colonies via migration. As an alternative hypothesis, we explore the role of recrudescence in persistence of Hendra virus in flying-fox populations via computer simulation using a model that integrates published information on the ecology of flying-foxes, and the ecology and epidemiology of Hendra virus. Simulated infection patterns agree with infection patterns observed in the field and suggest that Hendra virus could be maintained in an isolated flying-fox population indefinitely via periodic recrudescence in a manner indistinguishable from maintenance via periodic immigration of infected individuals. Further, post-recrudescence pulses of infectious flying-foxes provide a plausible basis for the observed seasonal clustering of equine cases. Correct understanding of the infection dynamics of Hendra virus in flying-foxes is fundamental to effectively managing risk of infection in horses and humans. Given the lack of clear empirical evidence on how the virus is maintained within populations, the role of recrudescence merits increased attention.

  10. Molecular phylogenetic profiling of gut-associated bacteria in larvae and adults of flesh flies.

    Science.gov (United States)

    Gupta, A K; Rastogi, G; Nayduch, D; Sawant, S S; Bhonde, R R; Shouche, Y S

    2014-12-01

    Flesh flies of the genus Sarcophaga (Diptera: Sarcophagidae) are carrion-breeding, necrophagous insects important in medical and veterinary entomology as potential transmitters of pathogens to humans and animals. Our aim was to analyse the diversity of gut-associated bacteria in wild-caught larvae and adult flesh flies using culture-dependent and culture-independent methods. Analysis of 16S rRNA gene sequences from cultured isolates and clone libraries revealed bacteria affiliated to Proteobacteria, Actinobacteria, Firmicutes and Bacteroidetes in the guts of larval and adult flesh flies. Bacteria cultured from larval and adult flesh fly guts belonged to the genera Acinetobacter, Bacillus, Budvicia, Citrobacter, Dermacoccus, Enterococcus, Ignatzschineria, Lysinibacillus, Myroides, Pasteurella, Proteus, Providencia and Staphylococcus. Phylogenetic analysis showed clone sequences of the genera Aeromonas, Bacillus, Bradyrhizobium, Citrobacter, Clostridium, Corynebacterium, Ignatzschineria, Klebsiella, Pantoea, Propionibacterium, Proteus, Providencia, Serratia, Sporosarcina, Weissella and Wohlfahrtiimonas. Species of clinically significant genera such as Ignatzschineria and Wohlfahrtiimonas spp. were detected in both larvae and adult flesh flies. Sequence analysis of 16S rRNA gene libraries supported culture-based results and revealed the presence of additional bacterial taxa. This study determined the diversity of gut microbiota in flesh flies, which will bolster the ability to assess microbiological risk associated with the presence of these flies. The present data thereby establish a platform for a much larger study. © 2014 The Royal Entomological Society.

  11. Flying-fox roost disturbance and Hendra virus spillover risk.

    Directory of Open Access Journals (Sweden)

    Daniel Edson

    Full Text Available Bats of the genus Pteropus (flying-foxes are the natural host of Hendra virus (HeV which periodically causes fatal disease in horses and humans in Australia. The increased urban presence of flying-foxes often provokes negative community sentiments because of reduced social amenity and concerns of HeV exposure risk, and has resulted in calls for the dispersal of urban flying-fox roosts. However, it has been hypothesised that disturbance of urban roosts may result in a stress-mediated increase in HeV infection in flying-foxes, and an increased spillover risk. We sought to examine the impact of roost modification and dispersal on HeV infection dynamics and cortisol concentration dynamics in flying-foxes. The data were analysed in generalised linear mixed models using restricted maximum likelihood (REML. The difference in mean HeV prevalence in samples collected before (4.9%, during (4.7% and after (3.4% roost disturbance was small and non-significant (P = 0.440. Similarly, the difference in mean urine specific gravity-corrected urinary cortisol concentrations was small and non-significant (before = 22.71 ng/mL, during = 27.17, after = 18.39 (P= 0.550. We did find an underlying association between cortisol concentration and season, and cortisol concentration and region, suggesting that other (plausibly biological or environmental variables play a role in cortisol concentration dynamics. The effect of roost disturbance on cortisol concentration approached statistical significance for region, suggesting that the relationship is not fixed, and plausibly reflecting the nature and timing of disturbance. We also found a small positive statistical association between HeV excretion status and urinary cortisol concentration. Finally, we found that the level of flying-fox distress associated with roost disturbance reflected the nature and timing of the activity, highlighting the need for a 'best practice' approach to dispersal or roost modification activities

  12. Flying-Fox Roost Disturbance and Hendra Virus Spillover Risk

    Science.gov (United States)

    Edson, Daniel; Field, Hume; McMichael, Lee; Jordan, David; Kung, Nina; Mayer, David; Smith, Craig

    2015-01-01

    Bats of the genus Pteropus (flying-foxes) are the natural host of Hendra virus (HeV) which periodically causes fatal disease in horses and humans in Australia. The increased urban presence of flying-foxes often provokes negative community sentiments because of reduced social amenity and concerns of HeV exposure risk, and has resulted in calls for the dispersal of urban flying-fox roosts. However, it has been hypothesised that disturbance of urban roosts may result in a stress-mediated increase in HeV infection in flying-foxes, and an increased spillover risk. We sought to examine the impact of roost modification and dispersal on HeV infection dynamics and cortisol concentration dynamics in flying-foxes. The data were analysed in generalised linear mixed models using restricted maximum likelihood (REML). The difference in mean HeV prevalence in samples collected before (4.9%), during (4.7%) and after (3.4%) roost disturbance was small and non-significant (P = 0.440). Similarly, the difference in mean urine specific gravity-corrected urinary cortisol concentrations was small and non-significant (before = 22.71 ng/mL, during = 27.17, after = 18.39) (P= 0.550). We did find an underlying association between cortisol concentration and season, and cortisol concentration and region, suggesting that other (plausibly biological or environmental) variables play a role in cortisol concentration dynamics. The effect of roost disturbance on cortisol concentration approached statistical significance for region, suggesting that the relationship is not fixed, and plausibly reflecting the nature and timing of disturbance. We also found a small positive statistical association between HeV excretion status and urinary cortisol concentration. Finally, we found that the level of flying-fox distress associated with roost disturbance reflected the nature and timing of the activity, highlighting the need for a ‘best practice’ approach to dispersal or roost modification activities. The

  13. Natural infections of man-biting sand flies by Leishmania and Trypanosoma species in the northern Peruvian Andes.

    Science.gov (United States)

    Kato, Hirotomo; Gomez, Eduardo A; Cáceres, Abraham G; Vargas, Franklin; Mimori, Tatsuyuki; Yamamoto, Kento; Iwata, Hiroyuki; Korenaga, Masataka; Velez, Lenin; Hashiguchi, Yoshihisa

    2011-05-01

    The natural infection of sand flies by Leishmania species was studied in the Andean areas of Peru where cutaneous leishmaniasis caused by Leishmania (Viannia) peruviana is endemic. Sand flies were captured by human bait and Center for Disease Control (CDC) light trap catches at Nambuque and Padregual, Department of La Libertad, Peru, and morphologically identified. Among 377 female sand flies dissected, the two dominant man-biting species were Lutzomyia (Helcocyrtomyia) peruensis (211 flies) and Lutzomyia (Helcocyrtomyia) caballeroi (151 flies). Another sand fly species captured by light trap was Warileya phlebotomanica (15 flies). The natural infection of sand flies by flagellates was detected in 1.4% of Lu. (H.) peruensis and 2.6% of Lu. (H.) caballeroi, and the parasite species were identified as Le. (V.) peruviana and Trypanosoma avium, respectively, by molecular biological methods. The results indicated that the vector species responsible for the transmission of leishmaniasis in the study areas is Lu. (H.) peruensis. In addition, the presence of Trypanosoma in man-biting sand fly species means that more careful consideration is necessary for vector research in areas of Andean Peru where leishmaniasis is endemic.

  14. Susceptibility of low-chill blueberry cultivars to oriental fruit fly, mediterranean fruit fly, and melon fly (Diptera: Tephritidae)

    Science.gov (United States)

    Forced infestation studies were conducted to determine if fruits of southern highbush blueberries (Vaccinium corymbosum L. hybrids) are hosts for three invasive tephritid fruit flies. Fruits of 17 blueberry cultivars were exposed to gravid female flies of Bactrocera dorsalis (Hendel) (oriental frui...

  15. Mutations in the Borrelia burgdorferi Flagellar Type III Secretion System Genes fliH and fliI Profoundly Affect Spirochete Flagellar Assembly, Morphology, Motility, Structure, and Cell Division.

    Science.gov (United States)

    Lin, Tao; Gao, Lihui; Zhao, Xiaowei; Liu, Jun; Norris, Steven J

    2015-05-12

    The Lyme disease spirochete Borrelia burgdorferi migrates to distant sites in the tick vectors and mammalian hosts through robust motility and chemotaxis activities. FliH and FliI are two cytoplasmic proteins that play important roles in the type III secretion system (T3SS)-mediated export and assembly of flagellar structural proteins. However, detailed analyses of the roles of FliH and FliI in B. burgdorferi have not been reported. In this study, fliH and fliI transposon mutants were utilized to dissect the mechanism of the Borrelia type III secretion system. The fliH and fliI mutants exhibited rod-shaped or string-like morphology, greatly reduced motility, division defects (resulting in elongated organisms with incomplete division points), and noninfectivity in mice by needle inoculation. Mutants in fliH and fliI were incapable of translational motion in 1% methylcellulose or soft agar. Inactivation of either fliH or fliI resulted in the loss of the FliH-FliI complex from otherwise intact flagellar motors, as determined by cryo-electron tomography (cryo-ET). Flagellar assemblies were still present in the mutant cells, albeit in lower numbers than in wild-type cells and with truncated flagella. Genetic complementation of fliH and fliI mutants in trans restored their wild-type morphology, motility, and flagellar motor structure; however, full-length flagella and infectivity were not recovered in these complemented mutants. Based on these results, disruption of either fliH or fliI in B. burgdorferi results in a severe defect in flagellar structure and function and cell division but does not completely block the export and assembly of flagellar hook and filament proteins. Many bacteria are able to rapidly transport themselves through their surroundings using specialized organelles called flagella. In spiral-shaped organisms called spirochetes, flagella act like inboard motors and give the bacteria the ability to bore their way through dense materials (such as human

  16. Fly Ash as a Time Marker for Anthropocene Alluvial Sedimentation

    Science.gov (United States)

    Bettis, E. A., III; Grimley, D. A.; Anders, A. M.; Bates, B.; Hannan, E.

    2014-12-01

    Human land use has transformed the landscapes, ecosystems and hydrology of the North American Midcontinent. One widespread impact of this transformation is increased runoff and accelerated soil erosion, which, along with direct human channel modifications and artificial drainage, have dramatically altered hydrologic and ecological conditions in streams and rivers with far-reaching results. A legacy of this change in streams and rivers is preserved on floodplains throughout the region in sediment known as post-settlement alluvium (PSA). Documenting the spatial and temporal pattern of historic floodplain sedimentation in the drainage network is part of a larger effort to understand decadal and century-scale sediment routing through the drainage system and the role of floodplain sedimentation in carbon sequestration. Fly ash, a product of high-temperature coal combustion, began to accumulate on the landscape in the early historic period (c.a.1840-1850 in Iowa and Illinois) as coal-burning technology such as steam engines came into use after 1850; prior to which no source of fly ash was present. Release of fly ash from coal burning in power plants and steam locomotives likely peaked in the early-mid 20th century. Fly ash particles (~ 1 to 10 % magnetic) are identified by their spheroidal shape and range in size from coarse clay to silt (~1-63µ). By identifying the percentage of fly ash spheroids in the magnetic separate (10 - 60µ size range) of a soil or sediment profile, the pre-fly ash Historic surface could be discerned. Application of this technique in selected localities in eastern Iowa (Clear Creek drainage) and central Illinois (Sangamon River drainage) resulted in successful demarcation of the PSA contact in areas where the boundary was physically evident. Bolstered by this success we were able to confidently demark the PSA contact in other settings where the boundary was not as physically evident. This relatively easy to implement, inexpensive tool will

  17. Self hardening property of Botswana fly ash | Sahu | Botswana ...

    African Journals Online (AJOL)

    Self hardening property of Botswana fly ash. ... In the present investigation, an effort has been made to study the self hardening property of Botswana fly ash by ... This will encourage the use of fly ash economically as a construction material.

  18. Sand flies (Diptera: Psychodidae) in the urban area of the municipality of Cianorte, Paraná State, Brazil.

    Science.gov (United States)

    Cerino, Daniela A; Teodoro, Ueslei; Silveira, Thaís G V

    2009-01-01

    The endemicity of American cutaneous leishmaniasis (ACL) in the Cianorte municipality, Paraná State the occurrence of human cases with the probable infection locus in the urban area, the presence of a permanently preserved modified native forest in the urban perimeter, and the lack of knowledge of the fauna of sand flies in the municipality provided the impetus for this study. The objective of this study was to assess the fauna, frequency and seasonality of the sand flies in the peridomicile, forest and urban area of this municipality. Sand flies were collected using Falcão light traps installed in the peridomicile and forest, from July 2005 to June 2006. A total of 755 sand flies were collected; Nyssomyia whitmani (Antunes & Coutinho) (84.0%), followed by Nyssomyia neivai (Pinto) (12.7%) were the predominant species. The number of sand flies collected in the peridomicile was significantly higher than in the forest (P = 0.0068). The small number of sand flies collected, especially in the forest, may be related to the modifications to the environment on the edge of the Parque Cinturão Verde, which surrounds the urban area of the municipality. Five species of sand flies were distinguished in the urban area of Cianorte, with greater frequencies found in the peridomicile, especially from November to April. Our data illustrate the necessity of maintaining the measures that contributed to reduce human contact with sand flies, thereby reducing the transmission risk of ACL.

  19. Investigation of the bacterial communities associated with females of Lutzomyia sand fly species from South America.

    Directory of Open Access Journals (Sweden)

    Mauricio R V Sant'Anna

    Full Text Available Phlebotomine sand flies are vectors of Leishmania that are acquired by the female sand fly during blood feeding on an infected mammal. Leishmania parasites develop exclusively in the gut lumen during their residence in the insect before transmission to a suitable host during the next blood feed. Female phlebotomine sand flies are blood feeding insects but their life style of visiting plants as well as animals, and the propensity for larvae to feed on detritus including animal faeces means that the insect host and parasite are exposed to a range of microorganisms. Thus, the sand fly microbiota may interact with the developing Leishmania population in the gut. The aim of the study was to investigate and identify the bacterial diversity associated with wild adult female Lutzomyia sand flies from different geographical locations in the New World. The bacterial phylotypes recovered from 16S rRNA gene clone libraries obtained from wild caught adult female Lutzomyia sand flies were estimated from direct band sequencing after denaturing gradient gel electrophoresis of bacterial 16 rRNA gene fragments. These results confirm that the Lutzomyia sand flies contain a limited array of bacterial phylotypes across several divisions. Several potential plant-related bacterial sequences were detected including Erwinia sp. and putative Ralstonia sp. from two sand fly species sampled from 3 geographically separated regions in Brazil. Identification of putative human pathogens also demonstrated the potential for sand flies to act as vectors of bacterial pathogens of medical importance in addition to their role in Leishmania transmission.

  20. Control of a free-flying robot manipulator system

    Science.gov (United States)

    Alexander, H.

    1986-01-01

    The development of and test control strategies for self-contained, autonomous free flying space robots are discussed. Such a robot would perform operations in space similar to those currently handled by astronauts during extravehicular activity (EVA). Use of robots should reduce the expense and danger attending EVA both by providing assistance to astronauts and in many cases by eliminating altogether the need for human EVA, thus greatly enhancing the scope and flexibility of space assembly and repair activities. The focus of the work is to develop and carry out a program of research with a series of physical Satellite Robot Simulator Vehicles (SRSV's), two-dimensionally freely mobile laboratory models of autonomous free-flying space robots such as might perform extravehicular functions associated with operation of a space station or repair of orbiting satellites. It is planned, in a later phase, to extend the research to three dimensions by carrying out experiments in the Space Shuttle cargo bay.

  1. A fly larva (Syrphidae: Ocyptamus that preys on adult flies

    Directory of Open Access Journals (Sweden)

    Onanchi Ureña

    2010-12-01

    Full Text Available Predatory syrphid larvae feed on relatively immobile prey, but here we report the first case (as far as we are aware of obligatory predation on very mobile prey. Larvae of an undescribed species of Ocyptamus (Diptera: Syrphidae were found in whitefly (Hemiptera: Aleyrodidae aggregations on the undersides of citrus leaves. However, instead of preying on the whitefly nymphs (as would be expected, the larvae preyed on adult flies (Diptera that were attracted to the honeydew. In the laboratory, larvae captured significantly more flies on whitefly infested leaves than on washed leaves, and generally abandoned leaves that lacked whiteflies. Most cases of successful prey capture involved flies that probed the anterior part of the larva’s body with its proboscis (as if it were honeydew. The syrphid larva lashed out at the fly and entangled it in sticky oral secretion. The prey did not recover when they were removed from the larva, suggesting that this new predatory species also employs venom to subdue its prey. Although the larvae consumed some honeydew, they were unable to complete their development on this diet. Two parasitoids were reared from Ocyptamus puparia, Proaspicera sp. (Hymenoptera: Figitidae and Paracarotomus sp. (Hymenoptera: Pteromalidae, both of which are endoparasitic koinobionts. Rev. Biol. Trop. 58 (4: 1157-1163. Epub 2010 December 01.Las larvas depredadoras de Syrphidae se alimentan de presas relativamente inmóviles, pero aquí reportamos el primer caso (hasta ahora conocido de la depredación obligatoria en presas muy móviles. Se encontraron las larvas de una especie no descrita de Ocyptamus (Diptera: Syrphidae juntas con ninfas de mosca blanca (Hemiptera: Aleyrodidae en el envés de las hojas de cítricos. Sin embargo, en vez de alimentarse de las ninfas de mosca blanca (como debería esperarse, las larvas se alimentaron de moscas adultas (Diptera que fueron atraídas a las excreciones azucaradas de la mosca blanca. En el

  2. Transcriptome analysis of reproductive tissue and intrauterine developmental stages of the tsetse fly (Glossina morsitans morsitans

    Directory of Open Access Journals (Sweden)

    Wu Yineng

    2010-03-01

    Full Text Available Abstract Background Tsetse flies, vectors of African trypanosomes, undergo viviparous reproduction (the deposition of live offspring. This reproductive strategy results in a large maternal investment and the deposition of a small number of progeny during a female's lifespan. The reproductive biology of tsetse has been studied on a physiological level; however the molecular analysis of tsetse reproduction requires deeper investigation. To build a foundation from which to base molecular studies of tsetse reproduction, a cDNA library was generated from female tsetse (Glossina morsitans morsitans reproductive tissues and the intrauterine developmental stages. 3438 expressed sequence tags were sequenced and analyzed. Results Analysis of a nonredundant catalogue of 1391 contigs resulted in 520 predicted proteins. 475 of these proteins were full length. We predict that 412 of these represent cytoplasmic proteins while 57 are secreted. Comparison of these proteins with other tissue specific tsetse cDNA libraries (salivary gland, fat body/milk gland, and midgut identified 51 that are unique to the reproductive/immature cDNA library. 11 unique proteins were homologus to uncharacterized putative proteins within the NR database suggesting the identification of novel genes associated with reproductive functions in other insects (hypothetical conserved. The analysis also yielded seven putative proteins without significant homology to sequences present in the public database (unknown genes. These proteins may represent unique functions associated with tsetse's viviparous reproductive cycle. RT-PCR analysis of hypothetical conserved and unknown contigs was performed to determine basic tissue and stage specificity of the expression of these genes. Conclusion This paper identifies 51 putative proteins specific to a tsetse reproductive/immature EST library. 11 of these proteins correspond to hypothetical conserved genes and 7 proteins are tsetse specific.

  3. Effects of anthropogenic disturbance and climate on patterns of bat fly parasitism.

    Directory of Open Access Journals (Sweden)

    Shai Pilosof

    Full Text Available Environmental conditions, including anthropogenic disturbance, can significantly alter host and parasite communities. Yet, our current knowledge is based mainly on endoparasites, while ectoparasites remain little studied. We studied the indirect effects of anthropogenic disturbance (human population density and climate (temperature, precipitation and elevation on abundance of highly host-specific bat flies in four Neotropical bat species across 43 localities in Venezuela. We formulated a set of 11 a priori hypotheses that included a combination of the two effectors and host species. Statistically, each of these hypotheses was represented by a zero-inflated negative binomial mixture model, allowing us to control for excess zeros in the data. The best model was selected using Akaike's information criteria. Fly abundance was affected by anthropogenic disturbance in Artibeus planirostris, Carollia perspicillata and Pteronotus parnellii, but not Desmodus rotundus. Climate affected fly abundance in all bat species, suggesting mediation of these effects via the host or by direct effects on flies. We conclude that human disturbance may play a role in shaping bat-bat fly interactions. Different processes could determine fly abundance in the different bat species.

  4. Fauna and abundance of medically important flies of Muscidae and Fanniidae (Diptera) in Tehran, Iran

    Institute of Scientific and Technical Information of China (English)

    MehdiKhoobdel; BehrozDavari

    2011-01-01

    Objective:To determine the faunal diversity of Muscidae and Fanniidae flies in Tehran, Iran. Methods:A net-capturing by direct observing method and fly trap were used to capture adult flies. To determine the fauna of flies in different habitats, 4 biotopes including corpse (human, birds, livestock), garbage and decaying organic matters, animal carcasses and human indoor habitat were selected. Big hashing nets (95 cm in diameter) have been used for adult flies capture in these biotopes. Results: In this study, totally 2 418 adult flies from 8 families including Muscidae, Fanniidae, Calliphoridae, Sarcophagidae, Tachinidae, Syrphidae, Anthomyiidae and Conopidae were captured. Among these, 1 279 belong to Muscidae and Fanniidae families. Four genera and 5 medically important species captured from two above mentioned families. Conclusions:Based on scientific documentation, 2 species of Muscina stabulans (M. stabulans) and Fannia scalaris (F. scalaris) are reported for the first time in Iran. However M. stabulans is a cosmopolitan species and its presence in Iran was probable.

  5. Multisensory systems integration for high-performance motor control in flies.

    Science.gov (United States)

    Frye, Mark A

    2010-06-01

    Engineered tracking systems 'fuse' data from disparate sensor platforms, such as radar and video, to synthesize information that is more reliable than any single input. The mammalian brain registers visual and auditory inputs to directionally localize an interesting environmental feature. For a fly, sensory perception is challenged by the extreme performance demands of high speed flight. Yet even a fruit fly can robustly track a fragmented odor plume through varying visual environments, outperforming any human engineered robot. Flies integrate disparate modalities, such as vision and olfaction, which are neither related by spatiotemporal spectra nor processed by registered neural tissue maps. Thus, the fly is motivating new conceptual frameworks for how low-level multisensory circuits and functional algorithms produce high-performance motor control.

  6. Requirements for satisfactory flying qualities of airplanes

    Science.gov (United States)

    Gilruth, R R

    1943-01-01

    Report discusses the results of an analysis of available data to determine what measured characteristics are significant in defining satisfactory flying qualities, what characteristics are reasonable to require of an airplane, and what influence the various design features have on the observed flying qualities.

  7. MODAL CONTROL OF PILOTLESS FLYING MACHINE

    Directory of Open Access Journals (Sweden)

    V. A. Antanevich

    2010-01-01

    Full Text Available The paper considers a problem on synthesis of lateral movement control algorithms in a pilotless flying machine which is made on the basis of a modal control method providing a required root arrangement of a characteristic closed control system polynom. Results of the modeling at stabilization of a lateral pilotless flying machine co-ordinate are presented in the paper.

  8. Flying Probe Tester: Architecture, Principle and Implementation

    Institute of Scientific and Technical Information of China (English)

    Fu,Xu; Fang,Kangling; Chen,Guoqing

    2005-01-01

    This paper introduces the flying probe tester, which is a testing device for PCB. The architecture and principle of flying probe tester are firstly introduced. Then the implementation of hardware and software is illuminated briefly. Finally, the optimizing method for the probe's moving path is researched based on the traveling salesman problem.

  9. Low back pain and low level flying

    NARCIS (Netherlands)

    J.C.F.M. Aghina

    1989-01-01

    textabstractLow level flying is a very good tactical possibility to carry out a mission unseen by a hostile radarsystem. Nowadays, Western Europe in general and the Federal Republic of Germany in particular, decreased . the permissions to low level flying in assigned regions. That's why the

  10. Testing for Mutagens Using Fruit Flies.

    Science.gov (United States)

    Liebl, Eric C.

    1998-01-01

    Describes a laboratory employed in undergraduate teaching that uses fruit flies to test student-selected compounds for their ability to cause mutations. Requires no prior experience with fruit flies, incorporates a student design component, and employs both rigorous controls and statistical analyses. (DDR)

  11. Catch Composition of Tsetse Flies (Glossina: Glossinidae

    Directory of Open Access Journals (Sweden)

    K. E. Okoh

    2011-01-01

    Full Text Available Problem statement: A study to determine the composition of tsetse flies species was conducted between January and December, 2007 in Kamuku National Park, Nigeria, using Biconical and Nitse traps. Tsetse flies were trapped along gallery forest in five streams for two trapping days and were collected daily. Approach: All tsetse flies caught were identified to species level, sexed, separated into teneral and non-teneral, hunger staged and Mean Hunger Stage computed. Fly density were calculated, the age structure examined using wing fray techniques for males and ovarian technique for females; the reproductive status of female flies were assessed. Two species of tsetse flies (Glossina palpalis palpalis robineau-desvoidy and Glossina tachinoides Westwood were caught in total of five hundred and two (502 flies. Out of these, 309(61.6% Glossina tachinoides and 193(38.4% G. palpalis were caught. Male catches (309, 61.6% were significantly (P Results: The estimated mean age for males was 11 days and females were 8 days. The insemination rate of 93.8% generally was high, G. tachinoides recorded 95.5% more than G. palpalis of 91.6%. Whereas parity rate (25.8% was low; G. palpalis was 37.4% while G. tachinoides parity rate is 17.2%. Conclusion: The study shows that two species of tsetse flies abound in the park although at low densities their presence may bear semblance to Trypanosomiasis and its impact to ecotourism.

  12. Physicochemical characterization of Spanish fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Querol, X.; Umana, J.C.; Alastuey, A.; Bertrana, C.; Lopez-Soler, A.; Plana, F.

    1999-12-01

    This article summarizes the results obtained from the physical, chemical, and mineralogical characterization of 14 fly ash samples. Major features that influence the utilization of each fly ash for zeolite synthesis are evidenced, and several fly ash types were selected as potential high-quality starting material for zeolite synthesis and ceramic applications. The main parameters influencing this selection were relatively small grain size; high Al and Si contents; high glass content; low CaO, S, and Fe contents; and relatively low heavy metal concentration. The Compostilla and Cou He fly ashes have high potential applications because of the low content of major impurities (such as Ca, Fe, and S) and the low content of soluble hazardous elements. The Espiel, Escucha, Los Barrios, As Pontes, Soto de Ribera, Meirama, Narcea, and Teruel fly ashes have important application potential, but this potential is slightly limited by the intermediate content of nonreactive impurities, such as Fe and Ca. The La Robla fly ash is of moderate interest, since the relatively high Ca and Fe oxide contents may reduce its potential applications. Finally, the Puertollano fly ash also has limited application because of the very high concentration of some heavy metals such as As, Cd, Ge, Hg, Pb, and Zn. From a mineralogical point of view, the Compostilla, Espiel, and Soto de Ribera fly ashes show the highest aluminum-silicate glass content and, consequently, the highest industrial application potential.

  13. Physiochemical characterization of Spanish fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Querol, X.; Umana, J.C.; Alastuey, A.; Bertrana, C.; Lopez Soler, A.; Plana, F.

    1999-12-01

    This article summarizes the results obtained from the physical, chemical, and mineralogical characterization of 14 fly ash samples. Major features that influence the utilization of each fly ash for zeolite synthesis are evidenced, and several fly ash types were selected as potential high-quality starting material for zeolite synthesis and ceramic applications. The main parameters influencing this selection were relatively small grain size; high Al and Si contents; high glass content; low CaO, S, and Fe contents; and relatively low heavy metal concentration. The Compostilla and Dou He fly ashes have high potential applications because of the low content of major impurities (such as Ca, Fe, and S) and the low content of soluble hazardous elements. The Espiel, Escucha, Los Barrios, As Pontes, Soto de Ribera, Meirama, Narcea, and Teruel fly ashes have important application potential, but this potential is slightly limited by the intermediate content of nonreactive impurities, such as Fe and Ca. The La Robla fly ash is of moderate interest, since the relatively high Ca and Fe oxide contents may reduce its potential applications. Finally, the Puertollano fly ash also has limited application because of the very high concentration of some heavy metals such as As, Cd, Ge, Hg, Pb, and Zn. From a mineralogical point of view, the Compostilla, Espiel, and Soto de Ribera fly ashes show the highest aluminum-silicate glass content and, consequently, the highest industrial application potential. (author)

  14. Low back pain and low level flying

    NARCIS (Netherlands)

    J.C.F.M. Aghina

    1989-01-01

    textabstractLow level flying is a very good tactical possibility to carry out a mission unseen by a hostile radarsystem. Nowadays, Western Europe in general and the Federal Republic of Germany in particular, decreased . the permissions to low level flying in assigned regions. That's why the Royal Ne

  15. Observações sobre parasitologia humana e veterinária em Mato Grosso Observations on human and veterinary parasitilogy in Mato-Grosso State

    Directory of Open Access Journals (Sweden)

    C. Pereira

    1941-01-01

    Full Text Available The most interesting observations were: 1 - The "mal de cadeiras" (believed to be an equine trypanosomose, due to Trypanosoma equinum is a syndrome originated from malnutrition, overwork, intense blood-loss through blood-sucking arthropods (chiefly tabanids and bot-flies and aggravated by the conditions prevailing in the "Pantanal" region of Mato-Grosso, when the waters of the Paraguay river basin ebb, after the periodic flood. The trypanosomes act only as one more factor contributing to the horses debility. 2 - The "curso preto dos bezerros" (calves black scour, usually attributed to poly-helminthoses, was observed to be related exclusively to pure Strongyloides papillosus infestations.

  16. Insecticide Treated Camouflage Sceening Reduces Sand Fly Numbers in Leishmania-Endemic Regions in Kenya

    Science.gov (United States)

    Current U.S. military operations in deserts face persistent threats from sand flies that transmit human Leishmania. In this study we investigated the efficacy of artificial barriers treated with residual insecticide to potentially reduce the risk of human infection from leishmaniasis by reducing the...

  17. Resistance and resilience of traditionally managed West African Dwarf goats from the savanna zone of northern Nigeria to naturally acquired trypanosome and gastrointestinal nematode infections.

    Science.gov (United States)

    Behnke, J M; Chiejina, S N; Musongong, G A; Nnadi, P A; Ngongeh, L A; Abonyi, F O; Fakae, B B

    2011-03-01

    A survey was conducted of gastrointestinal nematode infections and trypanosomosis in Nigerian West African Dwarf (WAD) goats from the savanna region of the country. Animals were screened at two markets, Gboko and Akpagher, from the beginning of April until the end of September, coinciding with the end of the dry season and the first 5 months of the wet season. Of 1054 goats that were examined, 80.5% carried gastrointestinal (GI) nematodes belonging to the genera Haemonchus (61.0%), Oesophagostomum (21.0%) and Trichostrongylus (17.9%). Faecal egg counts (FEC) increased very slowly but significantly from April to maximum levels in September, and varied marginally between the two market sources. The majority of goats (68.8 and 70.1% at the two markets) had low FEC not exceeding 50 eggs/g (epg). FEC did not differ significantly between the sexes or between age classes. Packed cell volume (PCV) also declined significantly with month of the study, but was affected by host sex (a significant month x sex interaction) being generally higher in male animals throughout the period. There was a highly significant negative correlation between log₁₀(FEC+1) and PCV, when all other factors had been taken into account. Body condition scores (BCS) also declined with month of the study, but there was a marked difference between the two sexes, with male animals generally showing a greater stability of BCS across the months compared with females. Trypanosome infections were found in only 4% of the goats and only during the rainy season. Most infections (92.86%) were caused by Trypanosoma brucei alone although T. vivax and T. congolense were occasionally detected. Overall, the majority of goats sampled each month maintained generally good body condition (BCS 3.0-5.0), normal or slightly reduced PCV, even when concurrently infected with trypanosomes and GI nematodes. However, four concurrently infected goats showed signs of overt anaemia during periods of peak infection, during the

  18. Construction procedures using self hardening fly ash

    Science.gov (United States)

    Thornton, S. I.; Parker, D. G.

    1980-07-01

    Fly ash produced in Arkansas from burning Wyoming low sulfur coal is self-hardening and can be effective as a soil stabilizing agent for clays and sands. The strength of soil-self hardening fly ash develops rapidly when compacted immediately after mixing. Seven day unconfined compressive strengths up to 1800 psi were obtained from 20% fly ash and 80% sand mixtures. A time delay between mixing the fly ash with the soil and compaction of the mixture reduced the strength. With two hours delay, over a third of the strength was lost and with four hours delay, the loss was over half. Gypsum and some commercial concrete retarders were effective in reducing the detrimental effect of delayed compaction. Adequate mixing of the soil and fly ash and rapid compaction of the mixtures were found to be important parameters in field construction of stabilized bases.

  19. TrackFly: virtual reality for a behavioral system analysis in free-flying fruit flies.

    Science.gov (United States)

    Fry, Steven N; Rohrseitz, Nicola; Straw, Andrew D; Dickinson, Michael H

    2008-06-15

    Modern neuroscience and the interest in biomimetic control design demand increasingly sophisticated experimental techniques that can be applied in freely moving animals under realistic behavioral conditions. To explore sensorimotor flight control mechanisms in free-flying fruit flies (Drosophila melanogaster), we equipped a wind tunnel with a Virtual Reality (VR) display system based on standard digital hardware and a 3D path tracking system. We demonstrate the experimental power of this approach by example of a 'one-parameter open loop' testing paradigm. It provided (1) a straightforward measure of transient responses in presence of open loop visual stimulation; (2) high data throughput and standardized measurement conditions from process automation; and (3) simplified data analysis due to well-defined testing conditions. Being based on standard hardware and software techniques, our methods provide an affordable, easy to replicate and general solution for a broad range of behavioral applications in freely moving animals. Particular relevance for advanced behavioral research tools originates from the need to perform detailed behavioral analyses in genetically modified organisms and animal models for disease research.

  20. Role of house flies in the ecology of Enterococcus faecalis from wastewater treatment facilities.

    Science.gov (United States)

    Doud, C W; Scott, H M; Zurek, L

    2014-02-01

    Enterococci are important nosocomial pathogens, with Enterococcus faecalis most commonly responsible for human infections. In this study, we used several measures to test the hypothesis that house flies, Musca domestica (L.), acquire and disseminate antibiotic-resistant and potentially virulent E. faecalis from wastewater treatment facilities (WWTF) to the surrounding urban environment. House flies and sludge from four WWTF (1-4) as well as house flies from three urban sites close to WWTF-1 were collected and cultured for enterococci. Enterococci were identified, quantified, screened for antibiotic resistance and virulence traits, and assessed for clonality. Of the 11 antibiotics tested, E. faecalis was most commonly resistant to tetracycline, doxycycline, streptomycin, gentamicin, and erythromycin, and these traits were intra-species horizontally transferrable by in vitro conjugation. Profiles of E. faecalis (prevalence, antibiotic resistance, and virulence traits) from each of WWTF sludge and associated house flies were similar, indicating that flies successfully acquired these bacteria from this substrate. The greatest number of E. faecalis with antibiotic resistance and virulence factors (i.e., gelatinase, cytolysin, enterococcus surface protein, and aggregation substance) originated from WWTF-1 that processed meat waste from a nearby commercial meat-processing plant, suggesting an agricultural rather than human clinical source of these isolates. E. faecalis from house flies collected from three sites 0.7-1.5 km away from WWTF-1 were also similar in their antibiotic resistance profiles; however, antibiotic resistance was significantly less frequent. Clonal diversity assessment using pulsed-field gel electrophoresis revealed the same clones of E. faecalis from sludge and house flies from WWTF-1 but not from the three urban sites close to WWTF-1. This study demonstrates that house flies acquire antibiotic-resistant enterococci from WWTF and potentially

  1. Predicting fruit fly's sensing rate with insect flight simulations

    National Research Council Canada - National Science Library

    Song Chang; Z. Jane Wang

    2014-01-01

    .... Interpreting our findings together with experimental results on fruit flies' reaction time and sensory motor reflexes, we conjecture that fruit flies sense their kinematic states every wing beat...

  2. Biomass fly ash in concrete: SEM, EDX and ESEM analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shuangzhen Wang; Larry Baxter; Fernando Fonseca [Brigham Young University, Provo, UT (USA). Department of Chemical Engineering

    2008-03-15

    This document summarizes microscopy study of concrete prepared from cement and fly ash (25% fly ash and 75% cement by weight), which covers coal fly ash and biomass fly ash. All the fly ash concrete has the statistical equal strength from one day to one year after mix. Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX) and environmental scanning electron microscopy (ESEM) analysis show that both coal and biomass fly ash particles undergo significant changes of morphology and chemical compositions in concrete due to pozzolanic reaction, although biomass fly ash differs substantially from coal fly ash in its fuel resources. 8 refs., 17 figs., 1 tab.

  3. Electrodialytic removal of heavy metals from fly ashes

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul

    2002-01-01

    The aim of the Ph.D. work was to develop the electrodialytic remediation method for removal of heavy metals from fly ashes. The work was focused on two types of fly ashes: fly ashes from wood combustion and fly ashes from municipal solid waste incineration.......The aim of the Ph.D. work was to develop the electrodialytic remediation method for removal of heavy metals from fly ashes. The work was focused on two types of fly ashes: fly ashes from wood combustion and fly ashes from municipal solid waste incineration....

  4. Avrocar: a real flying saucer

    CERN Document Server

    Fedrigo, Desire Francine G; Gobato, Alekssander

    2015-01-01

    One of the most unusual military aircraft programs V / STOL was the Avro VZ-9 "Avrocar". Designed to be a real flying saucer, the Avrocar was one of the few V / STOL to be developed in complete secrecy. Despite significant changes in the design, during flight tests, the Avrocar was unable to achieve its objectives, and the program was eventually canceled after an expenditure of 10 million US dollars between 1954 and 1961. But the concept of a lift fan, driven by a turbojet engine is not dead, and lives today as a key component of Lockheed X-35 Joint Strike Fighter contender. Was held in a data research and information related to Avrocar project carried out during the Second World War, which was directly linked to advances in aircraft that were built after it, and correlate them with the turbo fan engines used today.

  5. Protein: CAD [Trypanosomes Database

    Lifescience Database Archive (English)

    Full Text Available CAD carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotaseCAD trifunctional prot...eincarbamoylphosphate synthetase 2/aspartate transcarbamylase/dihydroorotasemultifunctional prot

  6. Anti-trypanosomal activity of 1,2,3,4,6-penta-O-galloyl-? -D-glucose isolated from Plectranthus barbatus Andrews (Lamiaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Roberta T. dos; Hiramoto, Liliane L.; Lago, Joao Henrique G.; Sartorelli, Patricia [Universidade Federal de Sao Paulo (UNIFESP), Diadema, SP (Brazil). Inst. de Ciencias Ambientais, Quimicas e Farmaceuticas; Tempone, Andre G.; Pinto, Erika G. [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Dept. de Parasitologia; Lorenzi, Harri, E-mail: psartorelli@unifesp.br [Instituto Plantarum de Estudos da Flora, Nova Odessa, SP (Brazil)

    2012-07-01

    MeOH extract from the leaves of Plectranthus barbatus Andrews (Lamiaceae), showed in vitro anti-trypanosomal activity. The bioassay-guided fractionation resulted in the isolation of a gallic acid derivative, identified as 1,2,3,4,6-penta-O-galloyl-{beta}-D-glucose (PGG), after thorough NMR and MS spectral analysis. Finally, this compound was tested against trypomastigote forms of T. cruzi and displayed an EC{sub 50} value of 67 {mu}M, at least 6.6-fold more effective than the standard drug benznidazole. This is the first occurrence of PGG in the Plectranthus genus and the first anti-parasitic activity described for PGG in the literature (author)

  7. Natural breeding places for phlebotomine sand flies (Diptera: psychodidae) in a semiarid region of bahia state, Brazil.

    Science.gov (United States)

    Sangiorgi, Bruno; Miranda, Daniel Neves; Oliveira, Diego Ferreira; Santos, Edivaldo Passos; Gomes, Fernanda Regis; Santos, Edna Oliveira; Barral, Aldina; Miranda, José Carlos

    2012-01-01

    Few microhabitats have been previously identified as natural breeding places for phlebotomine sand flies so far, and little is known about the influence of climate variables in their density. The present study was conducted in a dry region with a semiarid climate, where visceral leishmaniasis occurs in humans and dogs. The occurrence of breeding places in specific microhabitats was investigated in soil samples collected from five houses, which were also the location used for sampling of adults. All the microhabitats sampled by our study were identified as natural breeding places due to the occurrence of immature forms of sand flies. On a weekly basis, the number of adult sand flies captured was positively correlated with the mean temperature from preceding weeks. These results, in addition to promoting an advance in the knowledge of sand flies biology, may furnish a tool for optimizing the control of the sand flies, by indicating the most suitable periods and microhabitats for the application of insecticides.

  8. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett; Akash, Akash; Zhao, Qiang

    2013-01-08

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  9. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett; Akash, Akash; Zhao, Qiang

    2012-05-08

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  10. Treatment of fly ash for use in concrete

    Science.gov (United States)

    Boxley, Chett [Park City, UT

    2012-05-15

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with a quantity of spray dryer ash (SDA) and water to initiate a geopolymerization reaction and form a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 40%, and in some cases less than 20%, of the foam index of the untreated fly ash. An optional alkaline activator may be mixed with the fly ash and SDA to facilitate the geopolymerization reaction. The alkaline activator may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  11. Ablation of succinate production from glucose metabolism in the procyclic trypanosomes induces metabolic switches to the glycerol 3-phosphate/dihydroxyacetone phosphate shuttle and to proline metabolism.

    Science.gov (United States)

    Ebikeme, Charles; Hubert, Jane; Biran, Marc; Gouspillou, Gilles; Morand, Pauline; Plazolles, Nicolas; Guegan, Fabien; Diolez, Philippe; Franconi, Jean-Michel; Portais, Jean-Charles; Bringaud, Frédéric

    2010-10-15

    Trypanosoma brucei is a parasitic protist that undergoes a complex life cycle during transmission from its mammalian host (bloodstream forms) to the midgut of its insect vector (procyclic form). In both parasitic forms, most glycolytic steps take place within specialized peroxisomes, called glycosomes. Here, we studied metabolic adaptations in procyclic trypanosome mutants affected in their maintenance of the glycosomal redox balance. T. brucei can theoretically use three strategies to maintain the glycosomal NAD(+)/NADH balance as follows: (i) the glycosomal succinic fermentation branch; (ii) the glycerol 3-phosphate (Gly-3-P)/dihydroxyacetone phosphate (DHAP) shuttle that transfers reducing equivalents to the mitochondrion; and (iii) the glycosomal glycerol production pathway. We showed a hierarchy in the use of these glycosomal NADH-consuming pathways by determining metabolic perturbations and adaptations in single and double mutant cell lines using a combination of NMR, ion chromatography-MS/MS, and HPLC approaches. Although functional, the Gly-3-P/DHAP shuttle is primarily used when the preferred succinate fermentation pathway is abolished in the Δpepck knock-out mutant cell line. In the absence of these two pathways (Δpepck/(RNAi)FAD-GPDH.i mutant), glycerol production is used but with a 16-fold reduced glycolytic flux. In addition, the Δpepck mutant cell line shows a 3.3-fold reduced glycolytic flux compensated by an increase of proline metabolism. The inability of the Δpepck mutant to maintain a high glycolytic flux demonstrates that the Gly-3-P/DHAP shuttle is not adapted to the procyclic trypanosome context. In contrast, this shuttle was shown earlier to be the only way used by the bloodstream forms of T. brucei to sustain their high glycolytic flux.

  12. The response of trypanosomes and other eukaryotes to ER stress and the spliced leader RNA silencing (SLS) pathway in Trypanosoma brucei.

    Science.gov (United States)

    Michaeli, Shulamit

    2015-01-01

    The unfolded protein response (UPR) is induced when the quality control machinery of the cell is overloaded with unfolded proteins or when one of the functions of the endoplasmic reticulum (ER) is perturbed. Here, I describe UPR in yeast and mammals, and compare it to what we know about pathogenic fungi and the parasitic protozoans from the order kinetoplastida, focusing on the novel pathway the spliced leader silencing (SLS) in Trypanosoma brucei. Trypanosomes lack conventional transcription regulation, and thus, lack most of the UPR machinery present in other eukaryotes. Trypanosome genes are transcribed in polycistronic units that are processed by trans-splicing and polyadenylation. In trans-splicing, which is essential for processing of each mRNA, an exon known as the spliced leader (SL) is added to all mRNAs from a small RNA, the SL RNA. Under severe ER stress, T. brucei elicits the SLS pathway. In SLS, the transcription of the SL RNA gene is extinguished, and the entire transcription complex dissociates from the SL RNA promoter. Induction of SLS is mediated by an ER-associated kinase (PK3) that migrates to the nucleus, where it phosphorylates the TATA-binding protein (TRF4), leading shut-off of SL RNA transcription. As a result, trans-splicing is inhibited and the parasites activate a programmed cell death (PCD) pathway. Despite the ability to sense the ER stress, the different eukaryotes, especially unicellular parasites and pathogenic fungi, developed a variety of unique and different ways to sense and adjust to this stress in a manner different from their host.

  13. Fly ash-reinforced thermoplastic starch composites

    Energy Technology Data Exchange (ETDEWEB)

    Ma, X.F.; Yu, J.G.; Wang, N. [Tianjin University, Tianjin (China). School of Science

    2007-01-02

    As a by-product from the combustion of pulverized coal, fly ash was, respectively, used as the reinforcement for formamide and urea-plasticized thermoplastic starch (FUPTPS) and glycerol-plasticized thermoplastic starch (GPTPS). The introduction of fly ash improved tensile stress from 4.56 MPa to 7.78 MPa and Youngs modulus increased trebly from 26.8 MPa to 84.6 MPa for fly ash-reinforced FUPTPS (A-FUPTPS), while tensile stress increased from 4.55 MPa to 12.86 MPa and Youngs modulus increased six times from 76.4 MPa to 545 MPa for fly ash-reinforced GPTPS (A-GPTPS). X-ray diffractograms illustrated that fly ash destroyed the formation of starch ordered crystal structure, so both A-GPTPS and FUPTPS could resist the starch re-crystallization (retrogradation). Also fly ash improved water resistance of TPS. As shown by rheology, during the thermoplastic processing, the extruder screw speed effectively adjusted the flow behavior of A-FUPTPS, while the increasing of the processing temperature effectively ameliorated the flow behavior of A-GPTPS. However, superfluous ash contents (e.g., 20 wt%) worsened processing fluidity and resulted in the congregation of fly ash in FUPTPS matrix (tested by SEM) rather than in GPTPS matrix. This congregation decreased the mechanical properties and water resistance of the materials.

  14. How Spacecraft Fly Spaceflight Without Formulae

    CERN Document Server

    Swinerd, Graham

    2009-01-01

    About half a century ago a small satellite, Sputnik 1, was launched. The satellite did very little other than to transmit a radio signal to announce its presence in orbit. However, this humble beginning heralded the dawn of the Space Age. Today literally thousands of robotic spacecraft have been launched, many of which have flown to far-flung regions of the Solar System carrying with them the human spirit of scientific discovery and exploration. Numerous other satellites have been launched in orbit around the Earth providing services that support our technological society on the ground. How Spacecraft Fly: Spaceflight Without Formulae by Graham Swinerd focuses on how these spacecraft work. The book opens with a historical perspective of how we have come to understand our Solar System and the Universe. It then progresses through orbital flight, rocket science, the hostile environment within which spacecraft operate, and how they are designed. The concluding chapters give a glimpse of what the 21st century may ...

  15. Flies cope with uncontrollable stress by learned helplessness.

    Science.gov (United States)

    Yang, Zhenghong; Bertolucci, Franco; Wolf, Reinhard; Heisenberg, Martin

    2013-05-06

    In a wide range of animals, uncontrollable stressful events can induce a condition called "learned helplessness." In mammals it is associated with low general activity, poor learning, disorders of sleep and feeding, ulcers, and reduced immune status, as well as with increased serotonin in parts of the brain. It is considered an animal model of depression in humans. Here we investigate learned helplessness in Drosophila, showing that this behavioral state consists of a cognitive and a modulatory, possibly mood-like, component. A fly, getting heated as soon as it stops walking, reliably resumes walking to escape the heat. If, in contrast, the fly is not in control of the heat, it learns that its behavior has no effect and quits responding. In this state, the fly walks slowly and takes longer and more frequent rests, as if it were "depressed." This downregulation of walking behavior is more pronounced in females than in males. Learned helplessness in Drosophila is an example of how, in a certain situation, behavior is organized according to its expected consequences.

  16. Leishmania development in sand flies: parasite-vector interactions overview

    Directory of Open Access Journals (Sweden)

    Dostálová Anna

    2012-12-01

    Full Text Available Abstract Leishmaniases are vector-borne parasitic diseases with 0.9 – 1.4 million new human cases each year worldwide. In the vectorial part of the life-cycle, Leishmania development is confined to the digestive tract. During the first few days after blood feeding, natural barriers to Leishmania development include secreted proteolytic enzymes, the peritrophic matrix surrounding the ingested blood meal and sand fly immune reactions. As the blood digestion proceeds, parasites need to bind to the midgut epithelium to avoid being excreted with the blood remnant. This binding is strictly stage-dependent as it is a property of nectomonad and leptomonad forms only. While the attachment in specific vectors (P. papatasi, P. duboscqi and P. sergenti involves lipophosphoglycan (LPG, this Leishmania molecule is not required for parasite attachment in other sand fly species experimentally permissive for various Leishmania. During late-stage infections, large numbers of parasites accumulate in the anterior midgut and produce filamentous proteophosphoglycan creating a gel-like plug physically obstructing the gut. The parasites attached to the stomodeal valve cause damage to the chitin lining and epithelial cells of the valve, interfering with its function and facilitating reflux of parasites from the midgut. Transformation to metacyclic stages highly infective for the vertebrate host is the other prerequisite for effective transmission. Here, we review the current state of knowledge of molecular interactions occurring in all these distinct phases of parasite colonization of the sand fly gut, highlighting recent discoveries in the field.

  17. Marijuana effects on simulated flying ability.

    Science.gov (United States)

    Janowsky, D S; Meacham, M P; Blaine, J D; Schoor, M; Bozzetti, L P

    1976-04-01

    The authors studied the effects of marijuana intoxication on the ability of 10 certified airplane pilots to operate a flight simulator. They used a randomized double-blind crossover design to compare the effect of active versus placebo marijuana. They found that all 10 pilots showed a significant decrease in measurements of flying performance 30 minutes after smoking active marijuana. For a group of 6 pilots tested sequentially for 6 hours, a nonsignificant decrease in flying performance continued for 2 hours after smoking the active drug. The authors conclude that the effects of marijuana on flying performance may represent a sensitive indicator of the drug's psychomotor effects.

  18. Molecular detection and antimicrobial resistance of Klebsiella pneumoniae from house flies (Musca domestica) in kitchens, farms, hospitals and slaughterhouses.

    Science.gov (United States)

    Ranjbar, Reza; Izadi, Morteza; Hafshejani, Taghi T; Khamesipour, Faham

    2016-01-01

    Identifying disease vectors and pathogens is one of the key steps in controlling vector-borne diseases. This study investigated the possible role of house flies (Musca domestica) as vectors in the transmission of Klebsiella pneumoniae in Chaharmahal VA Bakhtiari and Isfahan provinces of Iran. House flies were captured from household kitchens, cattle farms, chicken farms, animal hospitals, human hospitals and slaughterhouses. Isolation of K. pneumoniae from external surfaces and guts of the flies was performed using MacConkey agar (MA) and thioglycollate broth (TGB). Identification of the isolates was performed with phenotypic techniques and polymerase chain reaction (PCR). A total of 600 house flies were sampled during the study period from different locations in four different seasons. Overall, 11.3% of the captured house flies were positive for K. pneumoniae. In Chaharmahal VA Bakhtiari province, the prevalence was 12.7%, while in Isfahan province, 10.0% of the sampled house flies were infected with K. pneumoniae. Season-wise, the highest prevalence of infections among the house flies was in summer. The organisms were highly resistant to ampicillin, amoxicillin, cefotaxime and piperacillin. A lowest level of resistance was observed for imipenem/cilastatin. The findings of this study demonstrated that house flies are potential vectors of antibiotic-resistant K. pneumoniae in Isfahan and Chaharmahal provinces, Iran. Control efforts for infections caused by this particular bacterium should take M. domestica into account.

  19. Seasonal variations in bacterial communities and antibiotic-resistant strains associated with green bottle flies (Diptera: Calliphoridae).

    Science.gov (United States)

    Wei, Ting; Ishida, Ryuichi; Miyanaga, Kazuhiko; Tanji, Yasunori

    2014-05-01

    Green bottle flies occur frequently around human environments in Japan. Many species of green bottle flies have been studied with regard to their importance in forensic examinations or clinical therapies, but the bacterial communities associated with this group of flies have not been comprehensively investigated. In this research, 454 pyrosequencing was used to reveal the bacterial communities in green bottle flies collected in different seasons. Meanwhile, the bacteria were screened with selective media and tested for antibiotic susceptibility. Samples collected in three different seasons harbored distinctive bacterial communities. The predominant genera associated with green bottles flies were Staphylococcus in spring, Ignatzschineria in summer, and Vagococcus, Dysgonomonas, and an unclassified Acetobacteraceae in autumn. An upward trend in bacterial community diversity was observed from spring to autumn. Changes in climatic conditions could be the cause of these seasonal variations in fly-associated bacterial communities. The species of isolated antibiotic-resistant bacteria also differed across seasons, but it was difficult to correlate seasonal changes in antibiotic-resistant bacteria with changes in whole communities. A number of multiple-antibiotic-resistant bacteria were isolated, and some of these strains were closely affiliated with pathogens such as Enterococcus faecalis and Enterococcus faecium, which could cause serious threats to public health. Overall, this research provided us with information about the composition and seasonality of bacterial communities in green bottle flies, and highlighted the risks of fly-mediated dissemination of antibiotic-resistant pathogens.

  20. Transfer of Escherichia coli O157:H7 to spinach by house flies, Musca domestica (Diptera: Muscidae).

    Science.gov (United States)

    Wasala, Lakmini; Talley, Justin L; Desilva, Udaya; Fletcher, Jacqueline; Wayadande, Astri

    2013-04-01

    Filth flies are known mechanical vectors of pathogenic bacteria in hospital and restaurant settings, but their role as vectors for disseminating microbes to plants has not been demonstrated. Escherichia coli O157:H7 deposition by flies onto spinach was studied using molecular, microbiological, and microscopy techniques. Relative quantitative polymerase chain reaction studies showed that bacteria acquired by flies from contaminated cattle manure and deposited in regurgitation spots on leaves survived and multiplied. Scanning electron microscopy of the regurgitation spots of flies exposed to manure inoculated with E. coli suggested the multiplication of bacteria-like organisms within the spots. This finding implies that the bacteria were active and is consistent with a hypothesis that regurgitation spots serve as a nutrition source allowing E. coli O157:H7 to survive on the spinach phylloplane. E. coli O157:H7 persisted on fly body surfaces up to 13 days after exposure to acquisition sources, suggesting that fly cuticular surfaces are conducive to the growth of this pathogen. These results are consistent with the hypothesis of bioenhanced transmission of human pathogens by house flies and suggest that filth flies may affect the microbial safety of fresh produce.

  1. Phlebotomine sand flies and canine infection in areas of human visceral leishmaniasis, Cuiabá, Mato Grosso Flebotomíneos e infecção canina em áreas de leishmaniose visceral humana, Cuiabá, Mato Grosso

    Directory of Open Access Journals (Sweden)

    Gustavo Leandro da Cruz Mestre

    2011-09-01

    Full Text Available Visceral leishmaniasis is a systemic infectious disease that can cause to a severe, potentially life-threatening chronic condition in humans. Risk factors for infection in urban areas have been associated with poor living conditions, the presence of sand fly vectors and infected pets. This study aimed to describe sand fly and canine infection in the neighborhoods of human visceral leishmaniasis occurrence in the city of Cuiabá, Mato Grosso State, central-western Brazil, reported between January 2005 and December 2006. A total of 1,909 sand flies were collected. They were predominantly males and the most frequent species were Lutzomyia cruzi (81.25%, Lutzomyia whitmani (13.88% and Lutzomyia longipalpis (2.62%. The sand fly density was not significantly correlated with the variation of environmental factors. The prevalence of canine visceral leishmaniasis in the neighborhoods studied was 26.82% and it was found that areas with high density of vectors coincided with areas of high prevalence of dogs and those with the highest rates of human cases. The study of vectors and other potential hosts are essential for a good understanding of visceral leishmaniasis and the related public health concerns, aiming at the prevention and control of leishmaniasis in the city of Cuiabá, Mato Grosso State.A leishmaniose visceral é uma doença infecciosa sistêmica, de evolução crônica grave, potencialmente fatal para o homem. Os fatores de risco para a infecção em áreas urbanas têm sido associados às precárias condições de moradia, à presença de flebotomíneos vetores e de animais domésticos infectados. O presente trabalho objetivou descrever a fauna flebotomínica e infecção canina nos bairros de ocorrência da leishmaniose visceral humana no município de Cuiabá, Mato Grosso, notificados no período de janeiro de 2005 a dezembro de 2006. Foram coletados 1.909 flebotomíneos, as espécies mais frequentes foram Lutzomyia cruzi (81,25%, Lutzomyia

  2. Enabling Spacecraft Formation Flying in Any Earth Orbit Through Spaceborne GPS and Enhanced Autonomy Technologies

    Science.gov (United States)

    Bauer, F. H.; Bristow, J. O.; Carpenter, J. R.; Garrison, J. L.; Hartman, K. R.; Lee, T.; Long, A. C.; Kelbel, D.; Lu, V.; How, J. P.; Busse, F.

    2000-01-01

    Formation flying is quickly revolutionizing the way the space community conducts autonomous science missions around the Earth and in space. This technological revolution will provide new, innovative ways for this community to gather scientific information, share this information between space vehicles and the ground, and expedite the human exploration of space. Once fully matured, this technology will result in swarms of space vehicles flying as a virtual platform and gathering significantly more and better science data than is possible today. Formation flying will be enabled through the development and deployment of spaceborne differential Global Positioning System (GPS) technology and through innovative spacecraft autonomy techniques, This paper provides an overview of the current status of NASA/DoD/Industry/University partnership to bring formation flying technology to the forefront as quickly as possible, the hurdles that need to be overcome to achieve the formation flying vision, and the team's approach to transfer this technology to space. It will also describe some of the formation flying testbeds, such as Orion, that are being developed to demonstrate and validate these innovative GPS sensing and formation control technologies.

  3. Spatial Distribution of Phlebotomine Sand Fly Species (Diptera: Psychodidae) in Qom Province, Central Iran.

    Science.gov (United States)

    Saghafipour, Abedin; Vatandoost, Hassan; Zahraei-Ramazani, Ali Reza; Yaghoobi-Ershadi, Mohammad Reza; Rassi, Yavar; Shirzadi, Mohammad Reza; Akhavan, Amir Ahmad

    2017-01-01

    Zoonotic cutaneous leishmaniasis (ZCL) is transmitted to humans by phlebotomine sand fly bites. ZCL is a major health problem in Iran, where basic knowledge gaps about sand fly species diversity persist in some ZCL-endemic areas. This paper describes the richness and spatial distribution of sand fly species, collected with sticky traps, in Qom province, a ZCL-endemic area in central Iran, where sand fly fauna has been poorly studied. Collected species were mapped on urban and rural digital maps based on a scale of 1/50,000. All analyses were undertaken with rural- and urban-level precision, i.e., rural and urban levels were our basic units of analysis. After identifying the sand flies, high-risk foci were determined. For spatial analysis of vector species population, the entomological sampling sites were geo-referenced using GPS. Arc GIS 9.3 software was used to determine the foci with leishmaniasis vector species. Following the analyses, two genera (Phlebotomus and Sergentomyia) and 14 species were identified. Based on the mapping and sand fly dispersion analysis, the rural districts were categorized into three groups-infection reported, without infection, and no report. Based on Geographical Information System analyses, Kahak and Markazi districts were identified as high-risk foci with leishmaniasis vector species. These findings can act as a help guide to direct active control measures to the identified high-risk foci and, eventually, lead to reduction in incidence of the disease.

  4. Neuronal encoding of sound, gravity, and wind in the fruit fly.

    Science.gov (United States)

    Matsuo, Eriko; Kamikouchi, Azusa

    2013-04-01

    The fruit fly Drosophila melanogaster responds behaviorally to sound, gravity, and wind. Exposure to male courtship songs results in reduced locomotion in females, whereas males begin to chase each other. When agitated, fruit flies tend to move against gravity. When faced with air currents, they 'freeze' in place. Based on recent studies, Johnston's hearing organ, the antennal ear of the fruit fly, serves as a sensor for all of these mechanosensory stimuli. Compartmentalization of sense cells in Johnston's organ into vibration-sensitive and deflection-sensitive neural groups allows this single organ to mediate such varied functions. Sound and gravity/wind signals sensed by these two neuronal groups travel in parallel from the fly ear to the brain, feeding into neural pathways reminiscent of the auditory and vestibular pathways in the human brain. Studies of the similarities between mammals and flies will lead to a better understanding of the principles of how sound and gravity information is encoded in the brain. Here, we review recent advances in our understanding of these principles and discuss the advantages of the fruit fly as a model system to explore the fundamental principles of how neural circuits and their ensembles process and integrate sensory information in the brain.

  5. Flying Through Dust From Asteroids

    Science.gov (United States)

    Kohler, Susanna

    2016-11-01

    How can we tell what an asteroid is made of? Until now, weve relied on remote spectral observations, though NASAs recently launched OSIRIS-REx mission may soon change this by landing on an asteroid and returning with a sample.But what if we could learn more about the asteroids near Earth without needing to land on each one? It turns out that we can by flying through their dust.The aerogel dust collector of the Stardust mission. [NASA/JPL/Caltech]Ejected CluesWhen an airless body is impacted by the meteoroids prevalent throughout our solar system, ejecta from the body are flung into the space around it. In the case of small objects like asteroids, their gravitational pull is so weak that most of the ejected material escapes, forming a surrounding cloud of dust.By flying a spacecraft through this cloud, we could perform chemical analysis of the dust, thereby determining the asteroids composition. We could even capture some of the dust during a flyby (for example, by using an aerogel collector like in the Stardust mission) and bring it back home to analyze.So whats the best place to fly a dust-analyzing or -collecting spacecraft? To answer this, we need to know what the typical distribution of dust is around a near-Earth asteroid (NEA) a problem that scientists Jamey Szalay (Southwest Research Institute) and Mihly Hornyi (University of Colorado Boulder) address in a recent study.The colors show the density distribution for dust grains larger than 0.3 m around a body with a 10-km radius. The distribution is asymmetric, with higher densities on the apex side, shown here in the +y direction. [Szalay Hornyi 2016]Moon as a LaboratoryTo determine typical dust distributions around NEAs, Szalay and Hornyi first look at the distribution of dust around our own Moon, caused by the same barrage of meteorites wed expect to impact NEAs. The Moons dust cloud was measured in situ in 2013 and 2014 by the Lunar Dust Experiment (LDEX) on board the Lunar Atmosphere and Dust Environment

  6. Evaluation of histone deacetylase inhibitors (HDACi) as therapeutic leads for human African trypanosomiasis (HAT).

    Science.gov (United States)

    Carrillo, Angela K; Guiguemde, W Armand; Guy, R Kiplin

    2015-08-15

    Two of the histone deacetylases, TbDAC1 and TbDAC3, have been reported to be essential genes in trypanosomes. Therefore, we tested the activity of a panel of human histone deacetylase inhibitors (HDACi) for their ability to block proliferation of Trypanosoma brucei brucei. Among the HDACi's, the hydroxamic acid derivatives panobinostat and belinostat exhibited potency that appeared to make them viable candidates for development due to their reported pharmacokinetic characteristics. However, cellular pharmacodynamic analysis demonstrated that these drugs were unable to kill cultured parasites at exposures seen in patients at their tolerated doses and additionally failed to show any synergistic effects in combination with pentamidine, suramin, melarsoprol, or nifurtimox. Analysis of the potency of the entire HDACi panel revealed no correlations between potency against any human HDAC isoform and inhibition of T. brucei proliferation, suggesting that the trypanosome histone deacetylases possess a unique specificity. These studies confirmed that HDAC inhibitors have potential as leads against human African trypanosomiasis but that none of the current clinical candidates can be directly repurposed. Therefore, development of HDACi's with appropriate specificity and potency may be a viable route to a new class of anti-trypanosomal drugs.

  7. FLI-1 Flightless-1 and LET-60 Ras control germ line morphogenesis in C. elegans

    Directory of Open Access Journals (Sweden)

    Dentler William L

    2008-05-01

    Full Text Available Abstract Background In the C. elegans germ line, syncytial germ line nuclei are arranged at the cortex of the germ line as they exit mitosis and enter meiosis, forming a nucleus-free core of germ line cytoplasm called the rachis. Molecular mechanisms of rachis formation and germ line organization are not well understood. Results Mutations in the fli-1 gene disrupt rachis organization without affecting meiotic differentiation, a phenotype in C. elegans referred to here as the germ line morphogenesis (Glm phenotype. In fli-1 mutants, chains of meiotic germ nuclei spanned the rachis and were partially enveloped by invaginations of germ line plasma membrane, similar to nuclei at the cortex. Extensions of the somatic sheath cells that surround the germ line protruded deep inside the rachis and were associated with displaced nuclei in fli-1 mutants. fli-1 encodes a molecule with leucine-rich repeats and gelsolin repeats similar to Drosophila flightless 1 and human Fliih, which have been shown to act as cytoplasmic actin regulators as well as nuclear transcriptional regulators. Mutations in let-60 Ras, previously implicated in germ line development, were found to cause the Glm phenotype. Constitutively-active LET-60 partially rescued the fli-1 Glm phenotype, suggesting that LET-60 Ras and FLI-1 might act together to control germ line morphogenesis. Conclusion FLI-1 controls germ line morphogenesis and rachis organization, a process about which little is known at the molecular level. The LET-60 Ras GTPase might act with FLI-1 to control germ line morphogenesis.

  8. Mobilization of iron from coal fly ash was dependent upon the particle size and the source of coal.

    Science.gov (United States)

    Smith, K R; Veranth, J M; Lighty, J S; Aust, A E

    1998-12-01

    Particulate air pollution, including coal fly ash, contains iron, and some of the pathological effects after inhalation may be due to reactive oxygen species produced by iron-catalyzed reactions. The objective of this study was to determine whether iron, present in coal fly ash, was mobilized, leading to ferritin induction in human airway epithelial cells, and whether the size of the particles affected the amount of iron mobilized. Three types of coal were used to generate the three size fractions of fly ash collected. The Utah coal fly ash was generated from a bituminous b coal, the Illinois coal fly ash from a bituminous c coal, and the North Dakota coal fly ash from a lignite a coal. Three size fractions were studied to compare the amount of iron mobilized in human airway epithelial (A549) cells and by citrate in cell-free suspensions. The size fractions selected were fine (airborne particulate matter fraction greater than 10 microm. Coal fly ash samples were incubated with 1 mM citrate to determine if iron associated with coal fly ash could be mobilized. Iron was mobilized by citrate from all three size fractions of all three coal types to levels as high as 56.7 nmol of Fe/mg of coal fly ash after 24 h. With all three coal types, more iron was mobilized by citrate from the fraction than from the >2.5 microm fractions. Further, the mobilized iron was in the Fe(III) form. To determine if iron associated with the coal fly ash could be mobilized by A549 cells, cells were treated with coal fly ash, and the amount of the iron storage protein ferritin was determined after 24 h. Ferritin levels were increased by as much as 11.9-fold in cells treated with coal fly ash. With two of the three types of coal studied, more ferritin was induced in cells treated with the fraction than with the >2.5 microm fractions. Further, inhibition of the endocytosis of the coal fly ash by the cells resulted in ferritin levels that were near that of the untreated cells, suggesting that

  9. Snowballing and flying under the radar

    DEFF Research Database (Denmark)

    Pötz, Katharina Anna; Hjortsø, Carsten Nico Portefée

    2013-01-01

    management and venture development paths. More specifically, flying under radar in terms of operating under lower institutional requirements, and slowly accumulating resources (snowballing) are major leveraging strategies. We integrate our results into a hypothesized framework for resource management in East...

  10. Dynamic Optimization Algorithm for Flying Trajectory of a Free-flying Space Robot

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new method of dynamic optimization for the flying trajectory of a free-flying space robot based on its flying motion characteristics is presented. The continuous flying trajectory is broken into a number of segment and the control efforts and the duration of the segment are chosen as the optimization parameters. The objective function is made by using the weighted sum of the fuel used and the time spent, and the constraint equations are selected. Finally, the internal point punishment function method is adopted in the optimization program, and the results of computer simulation are given.

  11. Effect of Fly Ash on the Electrical Conductivity of Concretes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The fly ash occasionally has high content of iron oxide and carbon that are good electrical conducting components. This paper investigates the effect of the fly ash used as mineral admixtures on the electrical conductivity of concretes. The electrical properties of concretes using 3 kinds of fly ash with different iron oxide contents have been studied. Experimental results show that at the same fly ash dosage the resistivity of concrete using fly ash with high content of iron oxide is slightly lower than that with low content of iron oxide. However, the concrete resistivity after 14d increases as fly ash dosage increases regardless of iron oxide content in fly ash.

  12. Campylobacter jejuni in Musca domestica: An examination of survival and transmission potential in light of the innate immune responses of the house flies

    DEFF Research Database (Denmark)

    Gill, Carson; Bahrndorff, Simon; Lowenberger, Carl

    2016-01-01

    The house fly, Musca domestica, has been implicated as a vector of Campylobacter spp., a major cause of human disease. Little is known whether house flies serve as biological amplifying hosts or mechanical vectors for Campylobacter jejuni. We investigated the period after C. jejuni had been inges...

  13. Relativistic Tennis Using Flying Mirror

    Science.gov (United States)

    Pirozhkov, A. S.; Kando, M.; Esirkepov, T. Zh.; Ma, J.; Fukuda, Y.; Chen, L.-M.; Daito, I.; Ogura, K.; Homma, T.; Hayashi, Y.; Kotaki, H.; Sagisaka, A.; Mori, M.; Koga, J. K.; Kawachi, T.; Daido, H.; Bulanov, S. V.; Kimura, T.; Kato, Y.; Tajima, T.

    2008-06-01

    Upon reflection from a relativistic mirror, the electromagnetic pulse frequency is upshifted and the duration is shortened by the factor proportional to the relativistic gamma-factor squared due to the double Doppler effect. We present the results of the proof-of-principle experiment for frequency upshifting of the laser pulse reflected from the relativistic "flying mirror", which is a wake wave near the breaking threshold created by a strong driver pulse propagating in underdense plasma. Experimentally, the wake wave is created by a 2 TW, 76 fs Ti:S laser pulse from the JLITE-X laser system in helium plasma with the electron density of ≈4-6×1019 cm-3. The reflected signal is observed with a grazing-incidence spectrograph in 24 shots. The wavelength of the reflected radiation ranges from 7 to 14 nm, the corresponding frequency upshifting factors are ˜55-115, and the gamma-factors are y = 4-6. The reflected signal contains at least 3×107 photons/sr. This effect can be used to generate coherent high-frequency ultrashort pulses that inherit temporal shape and polarization from the original (low-frequency) ones. Apart from this, the reflected radiation contains important information about the wake wave itself, e.g. location, size, phase velocity, etc.

  14. Biomass fly ash in concrete: Mixture proportioning and mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Shuangzhen Wang; Amber Miller; Emilio Llamazos; Fernando Fonseca; Larry Baxter [Brigham Young University, Provo, UT (USA). Department of Chemical Engineering

    2008-03-15

    ASTM C 618 prohibits use of biomass fly ashes in concrete. This document compares the properties of biomass fly ashes from cofired (herbaceous with coal), pure wood combustion and blended (pure wood fly ash blended with coal fly ash) to those of coal fly ash in concrete. The results illustrate that with 25% replacement (wt%) of cement by fly ash, the compressive strength (one day to one year) and the flexure strength (at 56th day curing) of cofired and blended biomass fly ash concrete is statistically equal to that of two coal fly ash concrete in this investigation (at 95% confidence interval). This implies that biomass fly ash with co-firing concentration within the concentration interest to commercial coal-biomass co-firing operations at power plants and blended biomass fly ash within a certain blending ratio should be considered in concrete. 37 refs., 10 figs., 2 tabs.

  15. My Friendship with the Flying Tigers

    Institute of Scientific and Technical Information of China (English)

    Jiang; Yingshan

    2015-01-01

    "I believe I owe a debt to the Chinese people...It’s so huge there’s no way I can pay it back."This is what Flying Tigers pilot Glen Beneda said to his family time and again.I have been working in the CPAFFC for over 10 years now,and my feelings for the Flying Tigers have deepened over time.I had heard of its

  16. Settling characteristics of some Indian fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Jain, M.K.; Sastry, B.S. [Indian Institute of Technology, Kharapur (India). Dept. of Mining Engineering

    2003-07-01

    The paper examines the aspects of the solid liquid separation (settling characteristics) of some of the fly ash obtained from coal-fired power plants in India. The application of a coagulating or flocculating agent (polymer) to improve the two properties as indicated is a typical industrial practice. The sources for this study comprise of fly ash, pond ash, and bottom ash and the settling characteristics are studied in conjunction with the flocculating agent polyacrylamide. 4 refs., 4 figs., 3 tabs.

  17. As and Se interactions with fly ashes

    Directory of Open Access Journals (Sweden)

    M. Díaz-Somoano

    2012-03-01

    Full Text Available Arsenic and selenium are toxic elements present incoal in trace concentrations that may be emitted tothe environment during coal conversion processes.However, it is possible to retain volatile arsenic andselenium compounds in the fly ashes originated bythe process, the proportions retained depending onthe characteristics of the ashes and processconditions. This work is focused on the capture ofthese elements in fly ashes in simulated coalcombustion and gasification atmospheres inlaboratory scale reactors.

  18. Wolbachia in Anastrepha fruit flies (Diptera: Tephritidae).

    Science.gov (United States)

    Coscrato, Virginia E; Braz, Antônio S K; P Perondini, André L; Selivon, Denise; Marino, Celso L

    2009-09-01

    Endosymbiotic bacteria of the genus Wolbachia are widespread among arthropods and cause a variety of reproductive abnormalities, such as cytoplasmic incompatibility, thelytokous parthenogenesis, male-killing, and host feminization. In this study, we used three sets of Wolbachia-specific primers (16S rDNA, ftsZ, and wsp) in conjunction with the polymerase chain reaction (PCR), cloning and sequencing to study the infection of fruit flies (Anastrepha spp. and Ceratitis capitata) by Wolbachia. The flies were collected at several localities in Brazil and at Guayaquil, Ecuador. All of the fruit flies studied were infected with Wolbachia supergroup A, in agreement with the high prevalence of this group in South America. Phylogenetic analysis showed that the wsp gene was the most sensitive gene for studying the relationships among Wolbachia strains. The Wolbachia sequences detected in these fruit flies were similar to those such as wMel reported for other fruit flies. These results show that the infection of Anastrepha fruit flies by Wolbachia is much more widespread than previously thought.

  19. 76 FR 26654 - Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist

    Science.gov (United States)

    2011-05-09

    ... Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist AGENCY: Animal and... from Mediterranean fruit fly quarantined areas in the United States with a certificate if the fruit is... quarantine regulations to remove trapping requirements for Mediterranean fruit fly for Hass avocados...

  20. Fly Eye radar: detection through high scattered media

    Science.gov (United States)

    Molchanov, Pavlo; Gorwara, Ashok

    2017-05-01

    Longer radio frequency waves better penetrating through high scattered media than millimeter waves, but imaging resolution limited by diffraction at longer wavelength. Same time frequency and amplitudes of diffracted waves (frequency domain measurement) provides information of object. Phase shift of diffracted waves (phase front in time domain) consists information about shape of object and can be applied for reconstruction of object shape or even image by recording of multi-frequency digital hologram. Spectrum signature or refracted waves allows identify the object content. Application of monopulse method with overlap closely spaced antenna patterns provides high accuracy measurement of amplitude, phase, and direction to signal source. Digitizing of received signals separately in each antenna relative to processor time provides phase/frequency independence. Fly eye non-scanning multi-frequency radar system provides simultaneous continuous observation of multiple targets and wide possibilities for stepped frequency, simultaneous frequency, chaotic frequency sweeping waveform (CFS), polarization modulation for reliable object detection. Proposed c-band fly eye radar demonstrated human detection through 40 cm concrete brick wall with human and wall material spectrum signatures and can be applied for through wall human detection, landmines, improvised explosive devices detection, underground or camouflaged object imaging.

  1. Comparative fly species composition on indoor and outdoor forensic cases in Malaysia.

    Science.gov (United States)

    Syamsa, Rizal Abdullah; Omar, Baharudin; Ahmad, Firdaus Mohd Salleh; Hidayatulfathi, Othman; Shahrom, Abd Wahid

    2017-01-01

    Forensic entomology refers to the science of collection and analysis of insect evidence in order to determine the minimum time period since death. This study aimed to investigate the occurrence of forensically important flies on 34 human remains referred to Universiti Kebangsaan Malaysia Medical Centre over a period of three years. Entomological specimens were collected at the death scenes and/or during autopsies. Live specimens were reared into adults while preserved specimens were processed for species identification. Five families, seven genera and nine species of flies were identified from human remains. The results of the study showed Chrysomya megacephala (Calliphoridae) maggots occurred on corpses with the highest frequency (70.6%), followed by Ch. rufifacies (Calliphoridae) (44.1%), sarcophagid fly (Sarcophagidae) (38.2%), Synthesiomya nudiseta (Muscidae) (20.6%), Megaselia scalaris (Phoridae) (14.7%), Lucilia cuprina (Calliphoridae) (5.9%), Ch. nigripes (Calliphoridae) (5.9%), Eristalis spp. (Syrphidae) (5.9%) and Hydrotaea spinigera (Muscidae) (2.9%). The greatest fly diversity occurred on remains recovered indoors (eight species) compared to outdoors (three species). Whilst, single and double infestations were common for both indoor and outdoor cases, multiple infestation of up to six species was observed in one of the indoor cases. Although large numbers of fly species were found on human remains, the predominant species were still those of Chrysomya, while S. nudiseta was found only on human remains recovered from indoors. The present study provides additional knowledge in the context of Malaysian forensic entomology and the distribution of forensically important flies which is of relevance to forensic science. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  2. Intrinsic Membrane Targeting of the Flagellar Export ATPase FliI: Interaction with Acidic Phospholipids and FliH

    OpenAIRE

    Auvray, Frédéric; Ozin, Amanda J.; Claret, Laurent; Hughes, Colin

    2002-01-01

    The specialised ATPase FliI is central to export of flagellar axial protein subunits during flagellum assembly. We establish the normal cellular location of FliI and its regulatory accessory protein FliH in motile Salmonella typhimurium, and ascertain the regions involved in FliH2/FliI heterotrimerisation. Both FliI and FliH localised to the cytoplasmic membrane in the presence and in the absence of proteins making up the flagellar export machinery and basal body. Membrane association was tig...

  3. Natural Hendra Virus Infection in Flying-Foxes - Tissue Tropism and Risk Factors.

    Directory of Open Access Journals (Sweden)

    Lauren K Goldspink

    Full Text Available Hendra virus (HeV is a lethal zoonotic agent that emerged in 1994 in Australia. Pteropid bats (flying-foxes are the natural reservoir. To date, HeV has spilled over from flying-foxes to horses on 51 known occasions, and from infected horses to close-contact humans on seven occasions. We undertook screening of archived bat tissues for HeV by reverse transcription quantitative polymerase chain reaction (RT-qPCR. Tissues were tested from 310 bats including 295 Pteropodiformes and 15 Vespertilioniformes. HeV was detected in 20 individual flying-foxes (6.4% from various tissues including spleen, kidney, liver, lung, placenta and blood components. Detection was significantly higher in Pteropus Alecto and P. conspicillatus, identifying species as a risk factor for infection. Further, our findings indicate that HeV has a predilection for the spleen, suggesting this organ plays an important role in HeV infection. The lack of detections in the foetal tissues of HeV-positive females suggests that vertical transmission is not a regular mode of transmission in naturally infected flying-foxes, and that placental and foetal tissues are not a major source of infection for horses. A better understanding of HeV tissue tropism will strengthen management of the risk of spillover from flying-foxes to horses and ultimately humans.

  4. Diet Shapes Mortality Response to Trauma in Old Tephritid Fruit Flies.

    Directory of Open Access Journals (Sweden)

    James R Carey

    Full Text Available Despite the importance of trauma in healthspan and lifespan in humans as well as in non-human species, with one important exception the literature in both gerontology and ecology contains virtually no experimental demographic studies concerned with trauma in any species. We used dietary manipulation [full diet (F versus sugar-only (S] to produce four levels of frailty in 55-day old tephritid fruit flies (Anastrepha ludens that were then subject to the trauma of cage transfer stress (n = 900/sex in each of the 4 treatments. The key results included the following: (1 there is a trauma effect caused by the transfer that depends on previous diet before transfer, new diet after transfer and gender of the fly; (2 males are more vulnerable than females; (3 if initial diet was F, flies are relatively immune against the trauma, and the subsequent diet (F or S does not matter; (4 however if initial diet was S, then the effect of the trauma depends largely on the diet after the transfer; (5 flies transferred from S to F diets do very well in terms of remaining longevity (i.e. greatest remaining longevity, while flies transferred from S to S diet do poorly (i.e. shortest remaining longevity. We discuss both the strengths and weaknesses of this study and implications of the results.

  5. At grammatical faculty of language, flies outsmart men.

    Science.gov (United States)

    Stoop, Ruedi; Nüesch, Patrick; Stoop, Ralph Lukas; Bunimovich, Leonid A

    2013-01-01

    Using a symbolic dynamics and a surrogate data approach, we show that the language exhibited by common fruit flies Drosophila ('D.') during courtship is as grammatically complex as the most complex human-spoken modern languages. This finding emerges from the study of fifty high-speed courtship videos (generally of several minutes duration) that were visually frame-by-frame dissected into 37 fundamental behavioral elements. From the symbolic dynamics of these elements, the courtship-generating language was determined with extreme confidence (significance level > 0.95). The languages categorization in terms of position in Chomsky's hierarchical language classification allows to compare Drosophila's body language not only with computer's compiler languages, but also with human-spoken languages. Drosophila's body language emerges to be at least as powerful as the languages spoken by humans.

  6. At grammatical faculty of language, flies outsmart men.

    Directory of Open Access Journals (Sweden)

    Ruedi Stoop

    Full Text Available Using a symbolic dynamics and a surrogate data approach, we show that the language exhibited by common fruit flies Drosophila ('D.' during courtship is as grammatically complex as the most complex human-spoken modern languages. This finding emerges from the study of fifty high-speed courtship videos (generally of several minutes duration that were visually frame-by-frame dissected into 37 fundamental behavioral elements. From the symbolic dynamics of these elements, the courtship-generating language was determined with extreme confidence (significance level > 0.95. The languages categorization in terms of position in Chomsky's hierarchical language classification allows to compare Drosophila's body language not only with computer's compiler languages, but also with human-spoken languages. Drosophila's body language emerges to be at least as powerful as the languages spoken by humans.

  7. Flying lemurs – The 'flying tree shrews'? Molecular cytogenetic evidence for a Scandentia-Dermoptera sister clade

    Directory of Open Access Journals (Sweden)

    Volobouev Vitaly

    2008-05-01

    Full Text Available Abstract Background Flying lemurs or Colugos (order Dermoptera represent an ancient mammalian lineage that contains only two extant species. Although molecular evidence strongly supports that the orders Dermoptera, Scandentia, Lagomorpha, Rodentia and Primates form a superordinal clade called Supraprimates (or Euarchontoglires, the phylogenetic placement of Dermoptera within Supraprimates remains ambiguous. Results To search for cytogenetic signatures that could help to clarify the evolutionary affinities within this superordinal group, we have established a genome-wide comparative map between human and the Malayan flying lemur (Galeopterus variegatus by reciprocal chromosome painting using both human and G. variegatus chromosome-specific probes. The 22 human autosomal paints and the X chromosome paint defined 44 homologous segments in the G. variegatus genome. A putative inversion on GVA 11 was revealed by the hybridization patterns of human chromosome probes 16 and 19. Fifteen associations of human chromosome segments (HSA were detected in the G. variegatus genome: HSA1/3, 1/10, 2/21, 3/21, 4/8, 4/18, 7/15, 7/16, 7/19, 10/16, 12/22 (twice, 14/15, 16/19 (twice. Reverse painting of G. variegatus chromosome-specific paints onto human chromosomes confirmed the above results, and defined the origin of the homologous human chromosomal segments in these associations. In total, G. variegatus paints revealed 49 homologous chromosomal segments in the HSA genome. Conclusion Comparative analysis of our map with published maps from representative species of other placental orders, including Scandentia, Primates, Lagomorpha and Rodentia, suggests a signature rearrangement (HSA2q/21 association that links Scandentia and Dermoptera to one sister clade. Our results thus provide new evidence for the hypothesis that Scandentia and Dermoptera have a closer phylogenetic relationship to each other than either of them has to Primates.

  8. Direct regulation of BCL-2 by FLI-1 is involved in the survival of FLI-1-transformed erythroblasts

    OpenAIRE

    Lesault, Isabelle; Tran Quang, Christine; Frampton, Jon; Ghysdael, Jacques

    2002-01-01

    Rearrangement of the FLI-1 locus with ensuing overexpression of FLI-1 is an early event in Friend murine leukemia virus-induced disease. When overexpressed in primary erythroblasts, FLI-1 blocks erythropoeitin (Epo)-induced terminal differentiation and inhibits apoptosis normally induced in response to Epo withdrawal. We show here that the survival-inducing property of FLI-1 is associated with increased transcription of BCL-2. We further show that FLI-1 binds BCL-2 promoter sequences in trans...

  9. Man-biting sand fly species and the natural infetion with Leishmania promastigote in leishmaniasis-endemic areas of Ecuador.

    OpenAIRE

    Hashiguchi, Yoshihisa

    2014-01-01

    A countrywide surveillance of sand flies was performed to obtain information on their geographical distribution and natural infection by Leishmania protozoa in Ecuador. A total of 18,119 sand flies were collected by human landing collections during 32 years from 1982 to 2014, and 29 species were recognized. The most prevalent 10 species were Lutzomyia gomezi, Lu. robusta, Lu. hartmanni, Lu. shannoni, Lu. trapidoi, Lu. panamensis, Lu. maranonensis, Lu. ayacuchensis, Lu. tortura and Lu. yuilli ...

  10. Acetylcholinesterases of blood-feeding flies and ticks.

    Science.gov (United States)

    Temeyer, Kevin B; Tuckow, Alexander P; Brake, Danett K; Li, Andrew Y; Pérez de León, Adalberto A

    2013-03-25

    Acetylcholinesterase (AChE) is the biochemical target of organophosphate (OP) and carbamate pesticides for invertebrates, vertebrate nerve agents, and AChE inhibitors used to reduce effects of Alzheimer's disease. Organophosphate pesticides (OPs) are widely used to control blood-feeding arthropods, including biting flies and ticks. However, resistance to OPs in pests affecting animal and human health has compromised control efficacy. OP resistance often results from mutations producing an OP-insensitive AChE. Our studies have demonstrated production of OP-insensitive AChEs in biting flies and ticks. Complementary DNA (cDNA) sequences encoding AChEs were obtained for the horn fly, stable fly, sand fly, and the southern cattle tick. The availability of cDNA sequences enables the identification of mutations, expression and characterization of recombinant proteins, gene silencing for functional studies, as well as in vitro screening of novel inhibitors. The southern cattle tick expresses at least three different genes encoding AChE in their synganglion, i.e. brain. Gene amplification for each of the three known cattle tick AChE genes and expression of multiple alleles for each gene may reduce fitness cost associated with OP-resistance. AChE hydrolyzes the neurotransmitter, acetylcholine, but may have additional roles in physiology and development. The three cattle tick AChEs possess significantly different biochemical properties, and are expressed in neural and non-neural tissues, which suggest separation of structure and function. The remarkable complexity of AChEs in ticks suggested by combining genomic data from Ixodes scapularis with our genetic and biochemical data from Rhipicephalus microplus is suggestive of previously unknown gene duplication and diversification. Comparative studies between invertebrate and vertebrate AChEs could enhance our understanding of structure-activity relationships. Research with ticks as a model system offers the opportunity to

  11. Population vulnerability and disability in Kenya's tsetse fly habitats.

    Directory of Open Access Journals (Sweden)

    Sue C Grady

    Full Text Available BACKGROUND: Human African Trypanosomiasis (HAT, also referred to as sleeping sickness, and African Animal Trypanosomaisis (AAT, known as nagana, are highly prevalent parasitic vector-borne diseases in sub-Saharan Africa. Humans acquire trypanosomiasis following the bite of a tsetse fly infected with the protozoa Trypanosoma brucei (T.b. spp. -i.e., T.b. gambiense in West and Central Africa and T.b. rhodesiense in East and Southern Africa. Over the last decade HAT diagnostic capacity to estimate HAT prevalence has improved in active case-finding areas but enhanced passive surveillance programs are still lacking in much of rural sub-Saharan Africa. METHODOLOGY/PRINCIPAL FINDINGS: This retrospective-cross-sectional study examined the use of national census data (1999 to estimate population vulnerability and disability in Kenya's 7 tsetse belts to assess the potential of HAT-acquired infection in those areas. A multilevel study design estimated the likelihood of disability in individuals, nested within households, nested within tsetse fly habitats of varying levels of poverty. Residents and recent migrants of working age were studied. Tsetse fly's impact on disability was conceptualised via two exposure pathways: directly from the bite of a pathogenic tsetse fly resulting in HAT infection or indirectly, as the potential for AAT takes land out of agricultural production and diseased livestock leads to livestock morbidity and mortality, contributing to nutritional deficiencies and poverty. Tsetse belts that were significantly associated with increased disability prevalence were identified and the direct and indirect exposure pathways were evaluated. CONCLUSIONS/SIGNIFICANCE: Incorporating reports on disability from the national census is a promising surveillance tool that may enhance future HAT surveillance programs in sub-Saharan Africa. The combined burdens of HAT and AAT and the opportunity costs of agricultural production in AAT areas are likely

  12. Expression of defensin paralogs across house fly life history: insights into fly-microbe interactions

    Science.gov (United States)

    House flies have a life-long association with microbe-rich environments. Larvae directly ingest bacteria in decaying substrates utilizing them for nutritional purposes. Adult house flies ephemerally associate with microbes, ingesting them either by direct feeding or indirectly during grooming. The h...

  13. Oral and Topical Toxicity of Fipronil to Melon Fly and Oriental Fruit Fly (Diptera: Tephritidae)

    Science.gov (United States)

    BACKGROUND: The objective of this study was to develop basic oral and topical toxicity data for Fipronil in Solulys protein bait to wild melon fly, Bactrocera cucurbitae (Coquillett) and the oriental fruit fly, Bactrocera dorsalis (Hendel). RESULTS: For the oral study, both females and males were ...

  14. New insights from Gorongosa National Park and Niassa National Reserve of Mozambique increasing the genetic diversity of Trypanosoma vivax and Trypanosoma vivax-like in tsetse flies, wild ungulates and livestock from East Africa.

    Science.gov (United States)

    Rodrigues, Carla Mf; Garcia, Herakles A; Rodrigues, Adriana C; Costa-Martins, André G; Pereira, Carlos L; Pereira, Dagmar L; Bengaly, Zakaria; Neves, Luis; Camargo, Erney P; Hamilton, Patrick B; Teixeira, Marta Mg

    2017-07-17

    Trypanosoma (Duttonella) vivax is a major pathogen of livestock in Africa and South America (SA), and genetic studies limited to small sampling suggest greater diversity in East Africa (EA) compared to both West Africa (WA) and SA. Multidimensional scaling and phylogenetic analyses of 112 sequences of the glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) gene and 263 sequences of the internal transcribed spacer of rDNA (ITS rDNA) were performed to compare trypanosomes from tsetse flies from Gorongosa National Park and Niassa National Reserve of Mozambique (MZ), wild ungulates and livestock from EA, and livestock isolates from WA and SA. Multidimensional scaling (MDS) supported Tvv (T. vivax) and TvL (T. vivax-like) evolutionary lineages: 1) Tvv comprises two main groups, TvvA/B (all SA and WA isolates plus some isolates from EA) and TvvC/D (exclusively from EA). The network revealed five ITS-genotypes within Tvv: Tvv1 (WA/EA isolates), Tvv2 (SA) and Tvv3-5 (EA). EA genotypes of Tvv ranged from highly related to largely different from WA/SA genotypes. 2) TvL comprises two gGAPDH-groups formed exclusively by EA sequences, TvLA (Tanzania/Kenya) and TvLB-D (MZ). This lineage contains more than 11 ITS-genotypes, seven forming the lineage TvL-Gorongosa that diverged from T. vivax Y486 enough to be identified as another species of the subgenus Duttonella. While gGAPDH sequences were fundamental for classification at the subgenus, major evolutionary lineages and species levels, ITS rDNA sequences permitted identification of known and novel genotypes. Our results corroborate a remarkable diversity of Duttonella trypanosomes in EA, especially in wildlife conservation areas, compared to the moderate diversity in WA. Surveys in wilderness areas in WA may reveal greater diversity. Biogeographical and phylogenetic data point to EA as the place of origin, diversification and spread of Duttonella trypanosomes across Africa, providing relevant insights towards the

  15. PROBA-3: Precise formation flying demonstration mission

    Science.gov (United States)

    Llorente, J. S.; Agenjo, A.; Carrascosa, C.; de Negueruela, C.; Mestreau-Garreau, A.; Cropp, A.; Santovincenzo, A.

    2013-01-01

    Formation Flying (FF) has generated a strong interest in many space applications, most of them involving a significant complexity for building for example on-board large "virtual structures or distributed observatories". The implementation of these complex formation flying missions with critical dependency on this new, advanced and critical formation technology requires a thorough verification of the system behaviour in order to provide enough guarantees for the target mission success. A significant number of conceptual or preliminary designs, analyses, simulations, and HW on-ground testing have been performed during the last years, but still the limitations of the ground verification determine that enough confidence of the behaviour of the formation flying mission will only be possible by demonstration in flight of the concept and the associated technologies. PROBA-3 is the mission under development at ESA for in-flight formation flying demonstration, dedicated to obtain that confidence and the necessary flight maturity level in the formation flying technologies for those future target missions. PROBA-3 will demonstrate technologies such as formation metrology sensors (from very coarse to highest accuracy), formation control and GNC, system operability, safety, etc. During the last years, PROBA-3 has evolved from the initial CDF study at ESA, to two parallel phase A studies, followed by a change in the industrial configuration for the Bridging step between A and B phases. Currently the SRR consolidation has been completed, and the project is in the middle of the phase B. After the phase A study SENER and GMV were responsible for the Formation Flying System, within a mission core team completed by OHB-Sweden, QinetiQ Space and CASA Espacio. In this paper an overview of the PROBA-3 mission is provided, with a more detailed description of the formation flying preliminary design and results.

  16. Flying Unmanned Aircraft: A Pilot's Perspective

    Science.gov (United States)

    Pestana, Mark E.

    2011-01-01

    The National Aeronautics and Space Administration (NASA) is pioneering various Unmanned Aircraft System (UAS) technologies and procedures which may enable routine access to the National Airspace System (NAS), with an aim for Next Gen NAS. These tools will aid in the development of technologies and integrated capabilities that will enable high value missions for science, security, and defense, and open the door to low-cost, extreme-duration, stratospheric flight. A century of aviation evolution has resulted in accepted standards and best practices in the design of human-machine interfaces, the displays and controls of which serve to optimize safe and efficient flight operations and situational awareness. The current proliferation of non-standard, aircraft-specific flight crew interfaces in UAS, coupled with the inherent limitations of operating UAS without in-situ sensory input and feedback (aural, visual, and vestibular cues), has increased the risk of mishaps associated with the design of the "cockpit." The examples of current non- or sub- standard design features range from "annoying" and "inefficient", to those that are difficult to manipulate or interpret in a timely manner, as well as to those that are "burdensome" and "unsafe." A concerted effort is required to establish best practices and standards for the human-machine interfaces, for the pilot as well as the air traffic controller. In addition, roles, responsibilities, knowledge, and skill sets are subject to redefining the terms, "pilot" and "air traffic controller", with respect to operating UAS, especially in the Next-Gen NAS. The knowledge, skill sets, training, and qualification standards for UAS operations must be established, and reflect the aircraft-specific human-machine interfaces and control methods. NASA s recent experiences flying its MQ-9 Ikhana in the NAS for extended duration, has enabled both NASA and the FAA to realize the full potential for UAS, as well as understand the implications of

  17. Fly Ash and Mercury Oxidation/Chlorination Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Sukh Sidhu; Patanjali Varanasi

    2008-12-31

    Mercury is a known pollutant that has detrimental effect on human health and environment. The anthropogenic emissions of mercury account for 10 to 30% of worldwide mercury emissions. There is a need to control/reduce anthropogenic mercury emissions. Many mercury control technologies are available but their effectiveness is dependent on the chemical form of mercury, because different chemical forms of mercury have different physical and chemical properties. Mercury leaves the boiler in its elemental form but goes through various transformations in the post-combustion zone. There is a need to understand how fly ash and flue gas composition affect speciation, partitioning, and reactions of mercury under the full range of post-combustion zone conditions. This knowledge can then be used to predict the chemical transformation of mercury (elemental, oxidized or particulate) in the post combustion zone and thus help with the control of mercury emissions from coal-burning power plants. To accomplish this goal present study was conducted using five coal fly ashes. These ashes were characterized and their catalytic activity was compared under selected reaction conditions in a fixed bed reactor. Based on the results from these fly ash experiments, three key components (carbon, iron oxide and calcium oxide) were chosen. These three components were then used to prepare model fly ashes. Silica/alumina was used as a base for these model fly ashes. One, two or three component model fly ashes were then prepared to investigate mercury transformation reactions. The third set of experiments was performed with CuO and CuCl2 catalysts to further understand the mercury oxidation process. Based on the results of these three studies the key components were predicted for different fly ash compositions under variety of flue gas conditions. A fixed bed reactor system was used to conduct this study. In all the experiments, the inlet concentration of Hg0(g) was maintained at 35 {micro}g/m3 using

  18. Glossina hytrosavirus control strategies in tsetse fly factories: application of infectomics in virus management

    NARCIS (Netherlands)

    Kariithi, H.M.

    2013-01-01

    African trypanosomosis is a fatal zoonotic disease transmitted by tsetse flies (Diptera; Glossinidae); blood-sucking insects found only in sub-Saharan Africa. Two forms of trypanosomoses occur: the animal African trypanosomosis (AAT; nagana), and the human African trypanosomosis (HAT; sleeping sickn

  19. Reality of Manned Flying Reactor

    CERN Document Server

    Zhuridov, Dmitry

    2013-01-01

    New concept for reducing dose radiation exposure, which helps to decrease the duration and cost of deep space human missions is introduced. This concept can be efficiently realized, using modern materials, such as carbon nanotube composites.

  20. Habitat analysis of North American sand flies near veterans returning from leishmania-endemic war zones

    Directory of Open Access Journals (Sweden)

    Keep Lisa

    2008-12-01

    much lower than on Fort Campbell. Conclusion A readily available land cover product can be used at the regional level to identify areas of sand fly habitat where human populations may be at higher risk of exposure. The sand fly density prediction maps can be used to direct further surveillance, insect control, or additional patient monitoring of potentially infected soldiers.

  1. Chorologie et infection par les trypanosomes de Glossina palpalis palpalis dans la forêt du banco et ses reliques, abidjan (Côte d’ivoire

    Directory of Open Access Journals (Sweden)

    Allou K.

    2009-12-01

    Full Text Available Dans le but de mettre en place un programme de lutte anti-vectorielle dans la périphérie d’Abidjan (Côte d’Ivoire, des enquêtes ont été effectuées pour évaluer les densités glossiniennes ainsi que les infections par les trypanosomes. Les captures ont été réalisées en saison des pluies et en saison sèche avec des pièges Vavoua posés pendant quatre jours consécutifs sur différents sites (forêt du Banco, Parc zoologique d’Abidjan, domaine de l’Université d’Abobo- Adjamé. Une seule espèce de glossine (Glossina palpalis palpalis et deux espèces de trypanosomes (Trypanosoma congolense, T. vivax ont été mises en évidence. La densité apparente par piège et par jour (DAP est très élevée au Parc zoologique, 54,8 glossines/piège/jour en saison sèche et 28,1 glossines/piège/jour en saison des pluies. À l’Université d’Abobo-Adjamé, la DAP est respectivement de 13,5 et 8,1 glossines/piège/jour en saison des pluies, et en saison sèche, elle n’est que de 0,9 et 0,8 dans la forêt du Banco. L’âge physiologique sur l’ensemble des sites est le suivant : 57,5 % de vieilles pares, 39 % de jeunes pares et 3,6 % de nullipares en saison des pluies. Ces proportions passent à 51,9 % de jeunes pares, 47,1 % de vieilles pares et 1 % de nullipares en saison sèche. Le taux global d’infection est estimé à 20,7 % en saison des pluies et à 20 % en saison sèche. Les analyses statistiques ont montré une différence significative dans la distribution des taux d’infections.

  2. Characteristics of MSWI fly ash during vitrification

    Institute of Scientific and Technical Information of China (English)

    TIAN Shu-lei; WANG Qi; WANG Qun-hui; MA Hong-zhi

    2009-01-01

    The vitrification characteristics of municipal solid waste incinerator (MSWI) fly ash were investigated. Effects of temperature on the binding efficiency of heavy metals, the change of chemical compositions and the weight loss of fly ash in the range of 800 - 1350 ℃ were studied. Toxicity Characteristic Leaching Procedure (TCLP) of the United States was used to analyze the leaching characteristics of heavy metals in fly ash and molten slag. Results indicate that chemical compositions, the weight loss of fly ash and the binding efficiency of heavy metals in fly ash have a tremendous change in the range of 1150 - 1260 ℃. The percentage of CaO, SiO2and AI203 increases with the increasing temperature, whereas it is contrary for SO3 , K2O, Na20 and CI; especially when the temperature is 1260 ℃, the percentage of these four elements decreases sharply from 43.72%to 0. 71%. The weight loss occurs obviously in the range of 1150 - 1260 ℃. Heavy metals of Pb and Cd are almost vaporized above 1000 ℃. Cr is not volatile and its binding efficiency can reach 100% below 1000 ℃. Resuits of TCLP indicate that the heavy metal content of molten slag is beyond stipulated limit values.

  3. Social attraction mediated by fruit flies' microbiome.

    Science.gov (United States)

    Venu, Isvarya; Durisko, Zachary; Xu, Jianping; Dukas, Reuven

    2014-04-15

    Larval and adult fruit flies are attracted to volatiles emanating from food substrates that have been occupied by larvae. We tested whether such volatiles are emitted by the larval gut bacteria by conducting tests under bacteria-free (axenic) conditions. We also tested attraction to two bacteria species, Lactobacillus brevis, which we cultured from larvae in our lab, and L. plantarum, a common constituent of fruit flies' microbiome in other laboratory populations and in wild fruit flies. Neither larvae nor adults showed attraction to axenic food that had been occupied by axenic larvae, but both showed the previously reported attraction to standard food that had been occupied by larvae with an intact microbiome. Larvae also showed significant attraction to volatiles from axenic food and larvae to which we added only either L. brevis or L. plantarum, and volatiles from L. brevis reared on its optimal growth medium. Controlled learning experiments indicated that larvae experienced with both standard and axenic used food do not perceive either as superior, while focal larvae experienced with simulated used food, which contains burrows, perceive it as superior to unused food. Our results suggest that flies rely on microbiome-derived volatiles for long-distance attraction to suitable food patches. Under natural settings, fruits often contain harmful fungi and bacteria, and both L. brevis and L. plantarum produce compounds that suppress the growth of some antagonistic fungi and bacteria. The larval microbiome volatiles may therefore lead prospective fruit flies towards substrates with a hospitable microbial environment.

  4. Investigation of gliding flight by flying fish

    Science.gov (United States)

    Park, Hyungmin; Jeon, Woo-Pyung; Choi, Haecheon

    2006-11-01

    The most successful flight capability of fish is observed in the flying fish. Furthermore, despite the difference between two medium (air and water), the flying fish is well evolved to have an excellent gliding performance as well as fast swimming capability. In this study, flying fish's morphological adaptation to gliding flight is experimentally investigated using dry-mounted darkedged-wing flying fish, Cypselurus Hiraii. Specifically, we examine the effects of the pectoral and pelvic fins on the aerodynamic performance considering (i) both pectoral and pelvic fins, (ii) pectoral fins only, and (iii) body only with both fins folded. Varying the attack angle, we measure the lift, drag and pitching moment at the free-stream velocity of 12m/s for each case. Case (i) has higher lift-to-drag ratio (i.e. longer gliding distance) and more enhanced longitudinal static stability than case (ii). However, the lift coefficient is smaller for case (i) than for case (ii), indicating that the pelvic fins are not so beneficial for wing loading. The gliding performance of flying fish is compared with those of other fliers and is found to be similar to those of insects such as the butterfly and fruitfly.

  5. Linear antigenic mapping of flagellin (FliC) from Salmonella enterica serovar Enteritidis with yeast surface expression system.

    Science.gov (United States)

    Wang, Gaoling; Shi, Bingtian; Li, Tao; Zuo, Teng; Wang, Bin; Si, Wei; Xin, Jiuqing; Yang, Kongbin; Shi, Xuanlin; Liu, Siguo; Liu, Henggui

    2016-02-29

    Salmonella enterica serovar Enteritidis (S. Enteritidis) is a major cause of food-borne illness around the world and can have significant health implications in humans, poultry and other animals. Flagellin (FliC) is the primary component of bacterial flagella. It has been shown that the FliC of S. Enteritidis is a significant antigenic structure and can elicit strong humoral responses against S. Enteritidis infection in chickens. Here, we constructed a FliC antigen library using a yeast surface expression system. Yeast cells expressing FliC peptide antigens were labeled with chicken sera against S. Enteritidis and sorted using FACS. The analyses of FliC peptides revealed that the FliC linear antigenicity in chickens resided on three domains which were able to elicit strong humoral responses in vivo. Animal experiments further revealed that the antibodies elicited by these antigenic domains were able to significantly inhibit the invasion of S. Enteritidis into the liver and spleen of chickens. These findings will facilitate our better understanding of the humoral responses elicited by FliC in chickens upon infection by S. Enteritidis.

  6. Characteristics of latrines in central Tanzania and their relation to fly catches.

    Directory of Open Access Journals (Sweden)

    Seth Irish

    Full Text Available The disposal of human excreta in latrines is an important step in reducing the transmission of diarrhoeal diseases. However, in latrines, flies can access the latrine contents and serve as a mechanical transmitter of diarrhoeal pathogens. Furthermore, the latrine contents can be used as a breeding site for flies, which may further contribute to disease transmission. Latrines do not all produce flies, and there are some which produce only a few, while others can produce thousands. In order to understand the role of the latrine in determining this productivity, a pilot study was conducted, in which fifty latrines were observed in and around Ifakara, Tanzania. The characteristics of the latrine superstructure, use of the latrine, and chemical characteristics of pit latrine contents were compared to the numbers of flies collected in an exit trap placed over the drop hole in the latrine. Absence of a roof was found to have a significant positive association (t=3.17, p=0.003 with the total number of flies collected, and temporary superstructures, particularly as opposed to brick superstructures (z=4.26, p<0.001, and increased total solids in pit latrines (z=2.57, p=0.01 were significantly associated with increased numbers of blowflies leaving the latrine. The number of larvae per gram was significantly associated with the village from which samples were taken, with the largest difference between two villages outside Ifakara (z=2.12, p=0.03. The effect of latrine superstructure (roof, walls on fly production may indicate that improvements in latrine construction could result in decreases in fly populations in areas where they transmit diarrhoeal pathogens.

  7. FlyBase: improvements to the bibliography.

    Science.gov (United States)

    Marygold, Steven J; Leyland, Paul C; Seal, Ruth L; Goodman, Joshua L; Thurmond, Jim; Strelets, Victor B; Wilson, Robert J

    2013-01-01

    An accurate, comprehensive, non-redundant and up-to-date bibliography is a crucial component of any Model Organism Database (MOD). Principally, the bibliography provides a set of references that are specific to the field served by the MOD. Moreover, it serves as a backbone to which all curated biological data can be attributed. Here, we describe the organization and main features of the bibliography in FlyBase (flybase.org), the MOD for Drosophila melanogaster. We present an overview of the current content of the bibliography, the pipeline for identifying and adding new references, the presentation of data within Reference Reports and effective methods for searching and retrieving bibliographic data. We highlight recent improvements in these areas and describe the advantages of using the FlyBase bibliography over alternative literature resources. Although this article is focused on bibliographic data, many of the features and tools described are applicable to browsing and querying other datasets in FlyBase.

  8. Attracting the attention of a fly.

    Science.gov (United States)

    Sareen, Preeti; Wolf, Reinhard; Heisenberg, Martin

    2011-04-26

    Organisms with complex visual systems rarely respond to just the sum of all visual stimuli impinging on their eyes. Often, they restrict their responses to stimuli in a temporarily selected region of the visual field (selective visual attention). Here, we investigate visual attention in the fly Drosophila during tethered flight at a torque meter. Flies can actively shift their attention; however, their attention can be guided to a certain location by external cues. Using visual cues, we can direct the attention of the fly to one or the other of the two visual half-fields. The cue can precede the test stimulus by several seconds and may also be spatially separated from the test by at least 20° and yet attract attention. This kind of external guidance of attention is found only in the lower visual field.

  9. Pigments of fly agaric (Amanita muscaria).

    Science.gov (United States)

    Stintzing, Florian; Schliemann, Willibald

    2007-01-01

    The complex pigment pattern of fly agaric (Amanita muscaria) cap skins has been studied by LC-DAD and mass spectrometry. Among the betaxanthins the corresponding derivatives of serine, threonine, ethanolamine, alanine, Dopa, phenylalanine and tryptophan are reported for the first time to contribute to the pigment pattern of fly agarics. Betalamic acid, the chromophoric precursor of betaxanthins and betacyanins, muscaflavin and seco-dopas were also detected. Furthermore, the red-purple muscapurpurin and the red muscarubrin were tentatively assigned while further six betacyanin-like components could not be structurally allocated. Stability studies indicated a high susceptibility of pigment extracts to degradation which led to rapid colour loss thus rendering a complete characterization of betacyanin-like compounds impossible at present. Taking into account these difficulties the presented results may be a starting point for a comprehensive characterization of the pigment composition of fly agarics.

  10. Research on Partner-fly Infrared Decoys

    Institute of Scientific and Technical Information of China (English)

    HONG Yang; LI Yan-jun; WANG Qi

    2006-01-01

    With the rapid development of new generation of infrared-guided missiles, it is very difficult for the traditional point-source infrared decoys to confront them. Therefore it is important to research the jamming mechanism and tactical application of infrared decoys. Through the research on rocket-propelled infrared decoys, a movement model and a radiation pattern of partner-fly infrared decoy are established based on the jamming mechanism of infrared centroid effect, the aerodynamics principle as well as the aeronautical dynamics principle. A dynamic simulation seeking superiority is conducted for its firing range and direction, a tactical application method of partner-fly infrared decoy against infrared-guided missile is explored, and the technical conditions of partner-fly infrared decoys are determined.

  11. Discriminating fever behavior in house flies.

    Directory of Open Access Journals (Sweden)

    Robert D Anderson

    Full Text Available Fever has generally been shown to benefit infected hosts. However, fever temperatures also carry costs. While endotherms are able to limit fever costs physiologically, the means by which behavioral thermoregulators constrain these costs are less understood. Here we investigated the behavioral fever response of house flies (Musca domestica L. challenged with different doses of the fungal entomopathogen, Beauveria bassiana. Infected flies invoked a behavioral fever selecting the hottest temperature early in the day and then moving to cooler temperatures as the day progressed. In addition, flies infected with a higher dose of fungus exhibited more intense fever responses. These variable patterns of fever are consistent with the observation that higher fever temperatures had greater impact on fungal growth. The results demonstrate the capacity of insects to modulate the degree and duration of the fever response depending on the severity of the pathogen challenge and in so doing, balance the costs and benefits of fever.

  12. INFLUENCE OF AMYLOSE STARCH ON DEVELOPMENT AND LIFESPAN OF FRUIT FLY DROSOPHILA MELANOGASTER

    Directory of Open Access Journals (Sweden)

    Oleksandra Abrat

    2015-05-01

    Full Text Available Last years, the concept of resistant starch (RS has evoked a new interest in researchers in the context of bioavailability of starch and its use as a source of dietary fiber. Based on clinical and animal research, RS has been proposed to be the most potentially beneficial starch fraction for human health. In this study, the effects of amylose starch as a fraction of RS on development and lifespan of fruit fly Drosophila melanogaster were investigated. In both Canton S and w1118 strains, the diet with 20% amylose RS delayed fly development, increased triacylglyceride level in the body of adult insects and reduced their lifespan compared to the diet with 4% amylose starch. Thus, our data clearly demonstrate that amylose starch at high concentrations may negatively affect fruit fly.

  13. Characterisation of the wildlife reservoir community for human and animal trypanosomiasis in the Luangwa Valley, Zambia.

    Directory of Open Access Journals (Sweden)

    Neil E Anderson

    2011-06-01

    Full Text Available Animal and human trypanosomiasis are constraints to both animal and human health in Sub-Saharan Africa, but there is little recent evidence as to how these parasites circulate in wild hosts in natural ecosystems. The Luangwa Valley in Zambia supports high densities of tsetse flies (Glossina species and is recognised as an historical sleeping sickness focus. The objective of this study was to characterise the nature of the reservoir community for trypanosomiasis in the absence of influence from domesticated hosts.A cross-sectional survey of trypanosome prevalence in wildlife hosts was conducted in the Luangwa Valley from 2005 to 2007. Samples were collected from 418 animals and were examined for the presence of Trypanosoma brucei s.l., T. b. rhodesiense, Trypanosoma congolense and Trypanosoma vivax using molecular diagnostic techniques. The overall prevalence of infection in all species was 13.9% (95% confidence interval [CI]: 10.71-17.57%. Infection was significantly more likely to be detected in waterbuck (Kobus ellipsiprymnus (Odds ratio [OR]=10.5, 95% CI: 2.36-46.71, lion (Panthera leo (OR=5.3, 95% CI: 1.40-19.69, greater kudu (Tragelaphus strepsiceros (OR=4.7, 95% CI: 1.41-15.41 and bushbuck (Tragelaphus scriptus (OR=4.5, 95% CI: 1.51-13.56. Bushbucks are important hosts for T. brucei s.l. while the Bovidae appear the most important for T. congolense. The epidemiology of T. vivax was less clear, but parasites were detected most frequently in waterbuck. Human infective T. b. rhodesiense were identified for the first time in African buffalo (Syncerus caffer and T. brucei s.l. in leopard (Panthera pardus. Variation in infection rates was demonstrated at species level rather than at family or sub-family level. A number of significant risk factors interact to influence infection rates in wildlife including taxonomy, habitat and blood meal preference.Trypanosoma parasites circulate within a wide and diverse host community in this bio

  14. Correlations between visual test results and flying performance on the advanced simulator for pilot training (ASPT).

    Science.gov (United States)

    Kruk, R; Regan, D; Beverley, K I; Longridge, T

    1981-08-01

    Looking for visual differences in pilots to account for differences in flying performance, we tested five groups of subjects: Air Force primary student jet pilots, graduating (T38 aircraft) students, Air Force pilot instructors, and two control groups made up of experienced nonpilot aircrew and nonflying civilians. This interim report compares 13 different visual test results with low-visibility landing performance on the Air Force Human Resources Laboratory ASPT simulator. Performance was assessed by the number of crashes and by the distance of the aircraft from the runway threshold at the time of the first visual flight correction. Our main finding was that, for student pilots, landing performance correlated with tracking performance for a target that changed size (as if moving in depth) and also with tracking performance for a target that moved sideways. On the other hand, landing performance correlated comparatively weakly with psychophysical thresholds for motion and contrast. For student pilots, several of the visual tests gave results that correlated with flying grades in T37 and T38 jet aircraft. Tracking tests clearly distinguished between the nonflying group and all the flying groups. On the other hand, visual threshold tests did not distinguish between nonflying and flying groups except for grating contrast, which distinguished between the nonflying group and the pilot instructors. The sideways-motion tracking task was sensitive enough to distinguish between the various flying groups.

  15. Competing visual flicker reveals attention-like rivalry in the fly brain

    Directory of Open Access Journals (Sweden)

    Bruno eVan Swinderen

    2012-10-01

    Full Text Available There is increasing evidence that invertebrates such as flies display selective attention (van Swinderen, 2011a, although parallel processing of simultaneous cues remains difficult to demonstrate in such tiny brains. Local field potential (LFP activity in the fly brain is associated with stimulus selection and suppression (van Swinderen and Greenspan, 2003;Tang and Juusola, 2010, like in other animals such as monkeys (Fries et al., 2001, suggesting that similar processes may be working to control attention in vastly different brains. To investigate selective attention to competing visual cues, I recorded brain activity from behaving flies while applying a method used in human attention studies: competing visual flicker, or frequency tags (Vialatte et al., 2010. Behavioral fixation in a closed-loop flight arena increased the response to visual flicker in the fly brain, and visual salience modulated responses to competing tags arranged in a center-surround pattern. Visual competition dynamics in the fly brain were dependent on the rate of pattern presentation, suggesting that attention-like switching in insects is tuned to the pace of visual changes in the environment rather than simply the passage of time.

  16. Phlebotomine Sand Flies (Diptera: Psychodidae) in Iran and their Role on Leishmania Transmission.

    Science.gov (United States)

    Yaghoobi-Ershadi, Mr

    2012-01-01

    Sand fly research has a long history in Iran beginning with the work of Adler, Theodor and Lourie in 1930 and followed by Mesghali's foundational taxonomic work on sand flies in 1943. Since then, research has been continued unabated throughout the country and official publications report the existence of at least 44 species of sand flies (26 of the genus Phlebotomus and 18 of genus Sergentomyia) in Iran. So far, seven Phlebotomus species and one Sergentomyia species have been collected and described by Iranian researchers for the first time. Natural promastigote infections have been repeatedly found in 13 species of sand flies and modern molecular techniques are used routinely to characterize Leishmania parasite isolates from endemic areas of cutaneous and visceral leishmaniasis. Because of anthropogenic environmental modifications or human population movements, data on phlebotomine sand flies should be regularly updated and verified at least every five years by fieldwork and taxonomy in foci of leishmaniasis, to incriminate vector species of relevance to the ecology of transmission and to support development and implementation of control programs.

  17. Phlebotomine Sand Flies (Diptera: Psychodidae in Iran and their Role on Leishmania Transmission

    Directory of Open Access Journals (Sweden)

    MR Yaghoobi-Ershadi

    2012-06-01

    Full Text Available Sand fly research has a long history in Iran beginning with the work of Adler, Theodor and Lourie in 1930 and followed by Mesghali’s foundational taxonomic work on sand flies in 1943. Since then, research has continued unabated throughout the country and official publications report the existence of at least 44 species of sand flies (26 of the genus Phlebotomus and 18 of genus Sergentomyia in Iran. So far, seven Phlebotomus species and one Sergentomyia species have been collected and described by Iranian researchers for the first time. Natural promastigote infection have been repeatedly found in 13 species of sand flies and modern molecular techniques are used routinely to characterize Leishmania parasite isolates from endemic areas of cutaneous and visceral leishmaniasis. Because of anthropogenic environmental modifications or human population movements, data on phlebotomine sand flies should be regularly updated and verified at least every five years by fieldwork and taxonomy in foci of leishmaniasis, to incriminate vector species of relevance to the ecology of transmission and to support development and implementation of control programs

  18. The Theory of Unified Relativity for a Biovielectroluminescence Phenomenon via Fly's Visual and Imaging System

    CERN Document Server

    Alipour, Philip B

    2007-01-01

    The elucidation upon fly's neuronal patterns as a link to computer graphics and memory cards I/O's, is investigated for the phenomenon by propounding a unified theory of Einstein's two known relativities. It is conclusive that flies could contribute a certain amount of neuromatrices indicating an imagery function of a visual-computational system into computer graphics and storage systems. The visual system involves the time aspect, whereas flies possess faster pulses compared to humans' visual ability due to the E-field state on an active fly's eye surface. This behaviour can be tested on a dissected fly specimen at its ommatidia. Electro-optical contacts and electrodes are wired through the flesh forming organic emitter layer to stimulate light emission, thereby to a computer circuit. The next step is applying a threshold voltage with secondary voltages to the circuit denoting an array of essential electrodes for bit switch. As a result, circuit's dormant pulses versus active pulses at the specimen's area ar...

  19. Bacterial Infection and Immune Responses in Lutzomyia longipalpis Sand Fly Larvae Midgut.

    Directory of Open Access Journals (Sweden)

    Matthew Heerman

    Full Text Available The midgut microbial community in insect vectors of disease is crucial for an effective immune response against infection with various human and animal pathogens. Depending on the aspects of their development, insects can acquire microbes present in soil, water, and plants. Sand flies are major vectors of leishmaniasis, and shown to harbor a wide variety of Gram-negative and Gram-positive bacteria. Sand fly larval stages acquire microorganisms from the soil, and the abundance and distribution of these microorganisms may vary depending on the sand fly species or the breeding site. Here, we assess the distribution of two bacteria commonly found within the gut of sand flies, Pantoea agglomerans and Bacillus subtilis. We demonstrate that these bacteria are able to differentially infect the larval digestive tract, and regulate the immune response in sand fly larvae. Moreover, bacterial distribution, and likely the ability to colonize the gut, is driven, at least in part, by a gradient of pH present in the gut.

  20. A Novel Method for Tracking Individuals of Fruit Fly Swarms Flying in a Laboratory Flight Arena.

    Science.gov (United States)

    Cheng, Xi En; Qian, Zhi-Ming; Wang, Shuo Hong; Jiang, Nan; Guo, Aike; Chen, Yan Qiu

    2015-01-01

    The growing interest in studying social behaviours of swarming fruit flies, Drosophila melanogaster, has heightened the need for developing tools that provide quantitative motion data. To achieve such a goal, multi-camera three-dimensional tracking technology is the key experimental gateway. We have developed a novel tracking system for tracking hundreds of fruit flies flying in a confined cubic flight arena. In addition to the proposed tracking algorithm, this work offers additional contributions in three aspects: body detection, orientation estimation, and data validation. To demonstrate the opportunities that the proposed system offers for generating high-throughput quantitative motion data, we conducted experiments on five experimental configurations. We also performed quantitative analysis on the kinematics and the spatial structure and the motion patterns of fruit fly swarms. We found that there exists an asymptotic distance between fruit flies in swarms as the population density increases. Further, we discovered the evidence for repulsive response when the distance between fruit flies approached the asymptotic distance. Overall, the proposed tracking system presents a powerful method for studying flight behaviours of fruit flies in a three-dimensional environment.

  1. A Novel Method for Tracking Individuals of Fruit Fly Swarms Flying in a Laboratory Flight Arena.

    Directory of Open Access Journals (Sweden)

    Xi En Cheng

    Full Text Available The growing interest in studying social behaviours of swarming fruit flies, Drosophila melanogaster, has heightened the need for developing tools that provide quantitative motion data. To achieve such a goal, multi-camera three-dimensional tracking technology is the key experimental gateway. We have developed a novel tracking system for tracking hundreds of fruit flies flying in a confined cubic flight arena. In addition to the proposed tracking algorithm, this work offers additional contributions in three aspects: body detection, orientation estimation, and data validation. To demonstrate the opportunities that the proposed system offers for generating high-throughput quantitative motion data, we conducted experiments on five experimental configurations. We also performed quantitative analysis on the kinematics and the spatial structure and the motion patterns of fruit fly swarms. We found that there exists an asymptotic distance between fruit flies in swarms as the population density increases. Further, we discovered the evidence for repulsive response when the distance between fruit flies approached the asymptotic distance. Overall, the proposed tracking system presents a powerful method for studying flight behaviours of fruit flies in a three-dimensional environment.

  2. Changeing of fly ash leachability after grinding

    Science.gov (United States)

    Lakatos, J.; Szabo, R.; Racz, A.; Banhidi, O.; Mucsi, G.

    2016-04-01

    Effect of grinding on the reactivity of fly ash used for geopolymer production was tested. Extraction technique using different alkaline and acidic solutions were used for detect the change of the solubility of elements due to the physical and mechano-chemical transformation of minerals in function of grinding time. Both the extraction with alkaline and acidic solution have detected improvement in solubility in function of grinding time. The enhancement in alkaline solution was approx. 100% in case of Si and Al. The acidic medium able to dissolve the fly ash higher manner than the alkaline, therefore the effect of grinding was found less pronounced.

  3. How mosquitoes fly in the rain

    Science.gov (United States)

    Dickerson, Andrew; Shankles, Peter; Madhavan, Nihar; Hu, David

    2011-11-01

    Mosquitoes thrive during rainfall and high humidity. If raindrops are 50 times heavier than mosquitoes, how do mosquitoes fly in the rain? In this combined experimental and theoretical study, we measure the impact force between a falling drop and a free-flying mosquito. High-speed videography of mosquitoes and custom-built mimics reveals a mosquito's low inertia renders it impervious to falling drops. Drops do not splash on mosquitoes, but simply push past them allowing a mosquito to continue on its flight path undeterred. We rationalize the force imparted using scaling relations based on the time of rebound between a falling drop and a free body of significantly less mass.

  4. Physical cleaning of high carbon fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Gray, McMahan L.; Champagne, Kenneth J.; Soong, Yee; Killmeyer, Richard P. [National Energy Technology Laboratory, US Department of Energy, P.O. Box 10940, Cochran Mills Roads, 15236 Pittsburgh, PA (United States); Maroto-Valer, M. Mercedes; Andresen, John M. [The Energy Institute, The Pennsylvania State University, 405 Academic Activities Building, 16802-2308 University Park, PA (United States); Ciocco, Michael V.; Zandhuis, Paul H. [Parson Project Services Inc, National Energy Technology Laboratory, P.O. Box 618, 15129 Library, Pittsburgh, PA (United States)

    2002-04-20

    An industrial fly ash sample was cleaned by three different processes, which were triboelectrostatic separation, ultrasonic column agglomeration, and column flotation. The unburned carbon concentrates were collected at purities ranging up to 62% at recoveries of 62%. In addition, optical microscopy studies were conducted on the final carbon concentrates to determine the carbon forms (inertinite, isotropic coke and anisotropic coke) collected from these various physical-cleaning processes. The effects of the various cleaning processes on the production of different carbon forms from high carbon fly ashes will be discussed.

  5. A FLYING WIRE SYSTEM IN THE AGS.

    Energy Technology Data Exchange (ETDEWEB)

    HUANG,H.; BUXTON,W.; MAHLER,G.; MARUSIC,A.; ROSER,T.; SMITH,G.; SYPHERS,M.; WILLIAMS,N.; WITKOVER,R.

    1999-03-29

    As the AGS prepares to serve as the injector for RHIC, monitoring and control of the beam transverse emittance become a major and important topic. Before the installation of the flying wire system, the emittance was measured with ionization profile monitors in the AGS, which require correction for space charge effects. It is desirable to have a second means of measuring profile that is less depend on intensity. A flying wire system has been installed in the AGS recently to perform this task. This paper discusses the hardware and software setup and the capabilities of the system.

  6. Novel trypanosome Trypanosoma gilletti sp. (Euglenozoa: Trypanosomatidae) and the extension of the host range of Trypanosoma copemani to include the koala ( Phascolarctos cinereus).

    Science.gov (United States)

    McInnes, L M; Hanger, J; Simmons, G; Reid, S A; Ryan, U M

    2011-01-01

    Trypanosoma irwini was previously described from koalas and we now report the finding of a second novel species, T. gilletti, as well as the extension of the host range of Trypanosoma copemani to include koalas. Phylogenetic analysis at the 18S rDNA and gGAPDH loci demonstrated that T. gilletti was genetically distinct with a genetic distance (± s.e.) at the 18S rDNA locus of 2.7 ± 0.5% from T. copemani (wombat). At the gGAPDH locus, the genetic distance (± s.e.) of T. gilletti was 8.7 ± 1.1% from T. copemani (wombat). Trypanosoma gilletti was detected using a nested trypanosome 18S rDNA PCR in 3/139 (∼2%) blood samples and in 2/29 (∼7%) spleen tissue samples from koalas whilst T. irwini was detected in 72/139 (∼52%) blood samples and T. copemani in 4/139 (∼3%) blood samples from koalas. In addition, naturally occurring mixed infections were noted in 2/139 (∼1.5%) of the koalas tested.

  7. Seroprevalence in chickens against campylobacter jejuni flagellar capping protein (FliD) in selected areas of the U.S

    Science.gov (United States)

    Campylobacter jejuni, a Gram-negative rod, is a zoonotic pathogen associated with human acute bacterial gastroenteritis. Poultry products are regarded as a major source for human infection with this microorganism. We have demonstrated that the flagellar capping protein (FliD) of C. jejuni is highl...

  8. Eco-friendly fly ash utilization: potential for land application

    Energy Technology Data Exchange (ETDEWEB)

    Malik, A.; Thapliyal, A. [Indian Institute of Technology Delhi, New Delhi (India)

    2009-07-01

    The increase in demand for power in domestic, agricultural, and industrial sectors has increased the pressure on coal combustion and aggravated the problem of fly ash generation/disposal. Consequently the research targeting effective utilization of fly ash has also gained momentum. Fly ash has proved to be an economical substitute for expensive adsorbents as well as a suitable raw material for brick manufacturing, zeolite synthesis, etc. Fly ash is a reservoir of essential minerals but is deficient in nitrogen and phosphorus. By amending fly ash with soil and/or various organic materials (sewage sludge, bioprocess materials) as well as microbial inoculants like mycorrhizae, enhanced plant growth can be realized. Based on the sound results of large scale studies, fly ash utilization has grown into prominent discipline supported by various internationally renowned organizations. This paper reviews attempts directed toward various utilization of fly ash, with an emphasis on land application of organic/microbial inoculants amended fly ash.

  9. Lixiviation of fly ash. Uitloging van vliegas

    Energy Technology Data Exchange (ETDEWEB)

    Verhagen, L.

    1988-01-01

    The lixiviation of a number of elements (Na, K, Ca, Mg, V, As, Sb and Hg) from different fly ash products (fired and cement bounded products) is investigated. A theoretical description of diffusion from a fly ash product is given as well as a standard test to determine the lixiviation rate. Lixiviation can be interpreted as a diffusion process. Diffusion of an element X from a fly ash product can be described with the following parameters: the effective diffusion coefficient, the fraction that is available for lixiviation and the tortuosity of the product. The physical meaning of the determined tortuosity is not clear. The behavior of tracers in the product is compared with the behavior of the corresponding element. Often this behavior deviates, sometimes even considerably. From a comparison of fly ash products it appears that cement bounded products are better able to combine with arsenicum and antimony than fired products. None of the investigated products caused concentrations of micro-elements way above the stated norm. Improvement as for lixiviation behavior of the products seems to be possible, in particular for bricks. 8 refs., 17 tabs., 26 figs.

  10. Have tsetse flies disappeared from Brazzaville town?

    Directory of Open Access Journals (Sweden)

    Patrick Bitsindou

    2009-08-01

    Full Text Available Background: From 1980 to 1985, the zoological park of Brazzaville was the only tsetse resting site located in downtown which supplied others temporary sites. The last trapping survey carried out in this area in 1987 showed that there were no more tsetse flies. Knowing that areas free of tsetse used to be reinvaded many years later, we have carried out an entomological survey in the area with the aim to verify what has happened more than twenty years later; given that suitable environmental conditions for Glossina are still available. Methods: Sixteen pyramidal traps were set out at the edge of the forest, along paths and around animal’s cages and were examined twice a day, at 10 a.m. and 4 p.m. during four days. Results: No tsetse fly was captured. Using the formula previously described; the probability of capturing a tsetse fly is 0.002. Conclusion: The zoological park seems close to be free of tsetse flies. Long-lasting surveys within the town and around are required before stating a complete disappearance of tsetse in the town.

  11. Formation flying; an interview with Tobias Gutleb

    NARCIS (Netherlands)

    Gutleb, T.; Perenboom, T.

    2011-01-01

    One of last year's Desig Synthesis Exercise (DSE) groups dived into the concept of fuel saving by letting aircraft flying in formation. They took their project even a step further and applied for the National Aviation Prize, a contest which encourages innovation in aerospace applications. The prize

  12. Refractive index of the fly rhabdomere

    NARCIS (Netherlands)

    Beersma, D.G.M.; Hoenders, B.J.; Huiser, A.M.J.; Toorn, P. van

    1982-01-01

    The refractive index and the diameter of the fly rhabdomere were determined by comparing the experimental results derived from interference microscopy with the results of a theoretical study on the scattering of plane waves by a homogeneous, isotropic cylindrical dielectric rod. It was found that

  13. Multicopter Design Challenge: Design, Fly, and Learn

    Science.gov (United States)

    Sutton, Kevin G.; Busby, Joe R.; Kelly, Daniel P.

    2016-01-01

    A great deal of the nation's attention has turned to the sky as new technologies open the door for new opportunities with unmanned aerial vehicles (UAVs). UAVs are powered aerial vehicles that do not carry an operator, use aerodynamic forces to provide vehicle lift, and can fly autonomously or be piloted remotely. As people become accustomed to…

  14. A Coincidental Sound Track for "Time Flies"

    Science.gov (United States)

    Cardany, Audrey Berger

    2014-01-01

    Sound tracks serve a valuable purpose in film and video by helping tell a story, create a mood, and signal coming events. Holst's "Mars" from "The Planets" yields a coincidental soundtrack to Eric Rohmann's Caldecott-winning book, "Time Flies." This pairing provides opportunities for upper elementary and…

  15. Decision-making capacity of flies

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Fruit flies (Drosophila melanogaster) can make appropriate choices among alternative flight options based on the relative salience of competing visual cues, according to a recent study by a team under the leadership of GUO Aike from the CAS Institute of Neuroscience.

  16. Formation flying; an interview with Tobias Gutleb

    NARCIS (Netherlands)

    Gutleb, T.; Perenboom, T.

    2011-01-01

    One of last year's Desig Synthesis Exercise (DSE) groups dived into the concept of fuel saving by letting aircraft flying in formation. They took their project even a step further and applied for the National Aviation Prize, a contest which encourages innovation in aerospace applications. The prize

  17. Volunteer Flying Organizations: Law Enforcements Untapped Resource

    Science.gov (United States)

    2016-12-01

    volunteers took on many of the following duties to help enable CAP functions: clerical work , aircraft maintenance , refueling operations, first aid...Highway Patrol, Monterey County Aero Squadron, Lane County Sheriff’s Office, Civil Air Patrol, volunteer flying organizations, law enforcement...5 3. Civil Air Patrol’s Use in Law Enforcement .................................7 D. POTENTIAL EXPLANATIONS AND HYPOTHESES

  18. FLY ASH: AN ALTERNATIVE TO POWDERED ACTIVATED ...

    African Journals Online (AJOL)

    Preferred Customer

    Also, fly ash has been found to be an efficient adsorbent for water treatment in the removal of ... properties for the removal of metal ions and organics; the residual sludge produced is used in ... investigate the reuse of the adsorbent for better economy of the process. ..... Ogbomoso, Oyo State, Nigeria to complete this article.

  19. The fruit flies (Tephritidae) of Ontario

    Science.gov (United States)

    Thirteen species of Tephritidae are newly recorded from Ontario, and alternative format keys are provided to the 31 genera and 72 species of fruit fly now known from, or likely to occur, in the province. Standard dichotomous keys to genera, and simplified field keys to genera and species are provide...

  20. Heavy metals in MSW incineration fly ashes

    DEFF Research Database (Denmark)

    Ferreira, Celia; Ribeiro, Alexandra B.; Ottosen, Lisbeth M.

    2003-01-01

    Incineration is a common solution for dealing with the increasing amount of municipal solid waste (MSW). During the process, the heavy metals initially present in the waste go through several transformations, ending up in combustion products, such as fly ash. This article deals with some issues r...

  1. Unidentified Flying Objects, A Selected Bibliography.

    Science.gov (United States)

    Rodgers, Kay, Comp.

    This bibliography, intended for the general reader, provides selective coverage of the unidentified flying object (UFO) literature that has appeared since 1969. The coverage is limited to English language works, but does include translations and materials published abroad. Other bibliographies are listed, as are books, congressional and other…

  2. Calcium homeostasis in fly photoreceptor cells

    NARCIS (Netherlands)

    Oberwinkler, J

    2002-01-01

    In fly photoreceptor cells, two processes dominate the Ca2+ homeostasis: light-induced Ca2+ influx through members of the TRP family of ion channels, and Ca2+ extrusion by Na+/Ca2+ exchange.Ca2+ release from intracellular stores is quantitatively insignificant. Both, the light-activated channels and

  3. "Lord of the Flies". [Lesson Plan].

    Science.gov (United States)

    Discovery Communications, Inc., Bethesda, MD.

    Based on William Golding's novel "Lord of the Flies," this lesson plan presents activities designed to help students understand that, on a literal level, the novel deals with what happens to a group of boys stranded on an island; and that on a symbolic level, it investigates what happens to civilized people when the structures of civilization…

  4. On Optical Crosstalk between Fly Rhabdomeres

    NARCIS (Netherlands)

    Wijngaard, W.; Stavenga, D.G.

    1975-01-01

    In a fly retinula light may be transferred among the rhabdomeres. It is estimated that the light from a point source imaged on the axis of a rhabdomere may eventually be transferred completely to a neighbouring rhabdomere. However, the effect on the sensitivity of this latter rhabdomere will remain

  5. Proteomics of Tsetse salivary glands before and after infection with Trypanosoma parasite

    NARCIS (Netherlands)

    Boeren, J.A.

    2016-01-01

    Trypanosoma brucei causes African trypanosomosis to humans and cattle, against which there are no effective vaccines or drugs. The tsetse fly Glossina morsitans morsitans is the primary vector of the species of T. brucei group. At the moment there is limited knowledge on how trypanosomes adapt to

  6. Measurement on Camber Deformation of Wings of Free-flying Dragonflies and Beating-flying Dragonflies

    Institute of Scientific and Technical Information of China (English)

    Deqiang Song; Lijiang Zeng

    2004-01-01

    The knowledge of wing orientation and deformation during flapping flight is necessary for a complete aerodynamic analysis, but to date those kinematic features have not been simultaneously quantified for free-flying insects. A projected comb-fringe (PCF) method has been developed for measuring spanwise camber changes on free-flying dragonflies and on beating-flying dragonflies through the course of a wingbeat, which bases on projecting a fringe pattern over the whole measurement area and then measuring the wing deformation from the distorted fringe pattern. Experimental results demonstrate substantial camber changes both along the wingspan and through the course of a wingbeat. The ratio of camber deformation to chord length for hind wing is up to 0.11 at 75% spanwise with a flapping angle of -0.66 degree for a free-flying dragonfly.

  7. Advanced control technology and airworthiness flying qualities requirements

    Science.gov (United States)

    Snyder, C. T.

    1976-01-01

    Flying quality requirements are specified in terms of the complete pilot-airframe-systems loop, the task, and the environment. Results from a study of flying qualities are reported. A review of the treatment of failure cases in various flying quality requirements is presented along with a description of the methods used and relevant lessons learned from recent Autoland certification programs.

  8. Caribbean Fruit Fly (Diptera: Tephritidae) and Small Fruit in Florida

    Science.gov (United States)

    Tephritid fruit flies are among the most important pests of fruits and vegetables worldwide. The Caribbean fruit fly, Anastrepha suspensa (Loew), is a tephritid pest that became established in Florida following introduction in 1965. Populations of this fruit fly also occur in Puerto Rico and Cuba, ...

  9. Pandora bullata (Entomophthorales) affecting calliphorid flies in Central Brazil

    Science.gov (United States)

    Fungi are where one finds them, and if one seeks fungal pathogens affecting flies, then a garbage dump may be an ideal place to find both persistent, abundant fly populations and their fungal pathogens. An obvious fungal epizootic affecting blue bottle flies, Chrysomyia megacephala (Diptera: Calliph...

  10. FlyAR: augmented reality supported micro aerial vehicle navigation.

    Science.gov (United States)

    Zollmann, Stefanie; Hoppe, Christof; Langlotz, Tobias; Reitmayr, Gerhard

    2014-04-01

    Micro aerial vehicles equipped with high-resolution cameras can be used to create aerial reconstructions of an area of interest. In that context automatic flight path planning and autonomous flying is often applied but so far cannot fully replace the human in the loop, supervising the flight on-site to assure that there are no collisions with obstacles. Unfortunately, this workflow yields several issues, such as the need to mentally transfer the aerial vehicle’s position between 2D map positions and the physical environment, and the complicated depth perception of objects flying in the distance. Augmented Reality can address these issues by bringing the flight planning process on-site and visualizing the spatial relationship between the planned or current positions of the vehicle and the physical environment. In this paper, we present Augmented Reality supported navigation and flight planning of micro aerial vehicles by augmenting the user’s view with relevant information for flight planning and live feedback for flight supervision. Furthermore, we introduce additional depth hints supporting the user in understanding the spatial relationship of virtual waypoints in the physical world and investigate the effect of these visualization techniques on the spatial understanding.

  11. Flies remember the time of day.

    Science.gov (United States)

    Chouhan, Nitin S; Wolf, Reinhard; Helfrich-Förster, Charlotte; Heisenberg, Martin

    2015-06-15

    The circadian clock enables organisms to anticipate daily environmental cycles and drives corresponding changes in behavior [1, 2]. Such endogenous oscillators also enable animals to display time-specific memory [1, 3-5]. For instance, mice and honeybees associate the location of a stimulus (like food or mate) with a certain time of day (time-place learning) [6, 7]. However, the mechanism underlying time-related learning and memory is not known. In the present study, we investigate time-specific odor learning. We use a genetically tractable animal, the fly Drosophila melanogaster. Starved flies are trained in the morning and afternoon to associate distinct odors with sucrose reward. The training is repeated the next day, and their time-dependent odor preference is tested on the third day. Our results indicate that Drosophila can express appetitive memory at the relevant time of day if the two conditioning events are separated by more than 4 hr. Flies can form time-odor associations in constant darkness (DD) as well as in a daily light-dark (LD) cycle, but not when kept under constant light (LL) conditions. Circadian clock mutants, period(01) (per(01)) and clock(AR) (clk(AR)), learned to associate sucrose reward with a certain odor but were unable to form time-odor associations. Our findings show that flies can utilize temporal information as an additional cue in appetitive learning. Time-odor learning in flies depends on a per- and clk-dependent endogenous mechanism that is independent of environmental light cues.

  12. Spatiotemporal Aspects of Hendra Virus Infection in Pteropid Bats (Flying-Foxes) in Eastern Australia

    Science.gov (United States)

    Field, Hume; Jordan, David; Edson, Daniel; Morris, Stephen; Melville, Debra; Parry-Jones, Kerryn; Broos, Alice; Divljan, Anja; McMichael, Lee; Davis, Rodney; Kung, Nina; Kirkland, Peter; Smith, Craig

    2015-01-01

    Hendra virus (HeV) causes highly lethal disease in horses and humans in the eastern Australian states of Queensland (QLD) and New South Wales (NSW), with multiple equine cases now reported on an annual basis. Infection and excretion dynamics in pteropid bats (flying-foxes), the recognised natural reservoir, are incompletely understood. We sought to identify key spatial and temporal factors associated with excretion in flying-foxes over a 2300 km latitudinal gradient from northern QLD to southern NSW which encompassed all known equine case locations. The aim was to strengthen knowledge of Hendra virus ecology in flying-foxes to improve spillover risk prediction and exposure risk mitigation strategies, and thus better protect horses and humans. Monthly pooled urine samples were collected from under roosting flying-foxes over a three-year period and screened for HeV RNA by quantitative RT-PCR. A generalised linear model was employed to investigate spatiotemporal associations with HeV detection in 13,968 samples from 27 roosts. There was a non-linear relationship between mean HeV excretion prevalence and five latitudinal regions, with excretion moderate in northern and central QLD, highest in southern QLD/northern NSW, moderate in central NSW, and negligible in southern NSW. Highest HeV positivity occurred where black or spectacled flying-foxes were present; nil or very low positivity rates occurred in exclusive grey-headed flying-fox roosts. Similarly, little red flying-foxes are evidently not a significant source of virus, as their periodic extreme increase in numbers at some roosts was not associated with any concurrent increase in HeV detection. There was a consistent, strong winter seasonality to excretion in the southern QLD/northern NSW and central NSW regions. This new information allows risk management strategies to be refined and targeted, mindful of the potential for spatial risk profiles to shift over time with changes in flying-fox species distribution

  13. Spatiotemporal Aspects of Hendra Virus Infection in Pteropid Bats (Flying-Foxes in Eastern Australia.

    Directory of Open Access Journals (Sweden)

    Hume Field

    Full Text Available Hendra virus (HeV causes highly lethal disease in horses and humans in the eastern Australian states of Queensland (QLD and New South Wales (NSW, with multiple equine cases now reported on an annual basis. Infection and excretion dynamics in pteropid bats (flying-foxes, the recognised natural reservoir, are incompletely understood. We sought to identify key spatial and temporal factors associated with excretion in flying-foxes over a 2300 km latitudinal gradient from northern QLD to southern NSW which encompassed all known equine case locations. The aim was to strengthen knowledge of Hendra virus ecology in flying-foxes to improve spillover risk prediction and exposure risk mitigation strategies, and thus better protect horses and humans. Monthly pooled urine samples were collected from under roosting flying-foxes over a three-year period and screened for HeV RNA by quantitative RT-PCR. A generalised linear model was employed to investigate spatiotemporal associations with HeV detection in 13,968 samples from 27 roosts. There was a non-linear relationship between mean HeV excretion prevalence and five latitudinal regions, with excretion moderate in northern and central QLD, highest in southern QLD/northern NSW, moderate in central NSW, and negligible in southern NSW. Highest HeV positivity occurred where black or spectacled flying-foxes were present; nil or very low positivity rates occurred in exclusive grey-headed flying-fox roosts. Similarly, little red flying-foxes are evidently not a significant source of virus, as their periodic extreme increase in numbers at some roosts was not associated with any concurrent increase in HeV detection. There was a consistent, strong winter seasonality to excretion in the southern QLD/northern NSW and central NSW regions. This new information allows risk management strategies to be refined and targeted, mindful of the potential for spatial risk profiles to shift over time with changes in flying-fox species

  14. Puncture resistance in 'Sharwil' avocado to oriental fruit fly and Mediterranean fruit fly (Diptera: Tephritidae) oviposition.

    Science.gov (United States)

    Follett, Peter A

    2009-06-01

    The physiological basis for host antibiosis or nonpreference to a quarantine pest is often not understood. Studies are needed on the mechanisms that impart resistance to better understand how resistance might fail. Experiments were conducted to examine the infestability of 'Sharwil' avocados by oriental fruit fly, Bactrocera dorsalis (Hendel), and Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), after harvest and to quantify the effect of avocado skin hardness on resistance to infestation by oriental fruit fly. Infestation rate increased with decreasing fruit firmness, but fruit were generally poor hosts. Fruit with a patch of skin removed produced more flies than intact fruit, suggesting that skin puncture resistance was an important deterrent to oviposition. This study showed that fruit can be infested within 1 d after harvest, suggesting that fruit should be transferred to fruit fly-proof containers as they are harvested to minimize the risk of attack. Although risk of infestation is negatively correlated with fruit firmness, even some hard fruit may become infested. Therefore, fruit firmness cannot be used alone as an indicator to ensure fruit fly-free 'Sharwil' avocados. Measuring fruit firmness may be a useful component of a multiple component systems approach as an additional safeguard to reduce risk of infestation.

  15. Effect of four commercial fungal formulations on mortality and sporulation of house flies (Musca domestica) and stable flies (Stomoxys calcitrans)

    Science.gov (United States)

    House flies (Musca domestica L.) and stable flies (Stomoxys calcitrans (L.)) (Diptera: Muscidae) are major pests of livestock. Biological control is an important tool in an integrated control framework. Increased mortality in filth flies has been documented with entomopathogenic fungi, and several s...

  16. Future fly ash marketing; Flugaschevermarktung in der Zukunft

    Energy Technology Data Exchange (ETDEWEB)

    Mauder, R.; Hugot, A. [Evonik Power Minerals GmbH, Dinslaken (Germany)

    2008-07-01

    It can be assumed that the fly ash production volumes will undergo a marked increase over the next few years. The conditions of fly ash production will improve as a result of modern and refurbished power plants, yielding a positive effect on the quality of fly ashes. Other vital parameters of future fly ash marketing are fly ash logistics and the infrastructure of power plants. Basically, economic utilisation of the increased production volumes is possible; however, new and long-term strategies are necessary. (orig.)

  17. Flies blown disease - Oral myiasis

    Directory of Open Access Journals (Sweden)

    Rahul Srivastava

    2011-01-01

    Full Text Available Myiasis, a term first introduced by Hope (1840, refers to the invasion of tissues and organs of animals and human wounds and certain body cavities by the dipteran larvae which manifests as subcutaneous furunculoid or boillike lesions. Oral myiasis is a rare pathology and a risk to the patient′s life. Higher incidence is seen in rural areas affecting the tropical and sub-tropical zones of Africa and America. Myiasis affecting the oro-dental complex is rare. Here is a case report of oral myiasis in an 18-year-old male patient who is mentally challenged with anterior open bite, incompetent lips, and periodontal disease. The lesion was treated with turpentine oil, which forced larvae out and irrigated with normal saline solution. Follow-up examination revealed complete remission and healing of the lesion.

  18. Cyclin-Dependent Kinase CRK9, Required for Spliced Leader trans Splicing of Pre-mRNA in Trypanosomes, Functions in a Complex with a New L-Type Cyclin and a Kinetoplastid-Specific Protein.

    Science.gov (United States)

    Badjatia, Nitika; Park, Sung Hee; Ambrósio, Daniela L; Kirkham, Justin K; Günzl, Arthur

    2016-03-01

    In eukaryotes, cyclin-dependent kinases (CDKs) control the cell cycle and critical steps in gene expression. The lethal parasite Trypanosoma brucei, member of the phylogenetic order Kinetoplastida, possesses eleven CDKs which, due to high sequence divergence, were generically termed CDC2-related kinases (CRKs). While several CRKs have been implied in the cell cycle, CRK9 was the first trypanosome CDK shown to control the unusual mode of gene expression found in kinetoplastids. In these organisms, protein-coding genes are arranged in tandem arrays which are transcribed polycistronically. Individual mRNAs are processed from precursor RNA by spliced leader (SL) trans splicing and polyadenylation. CRK9 ablation was lethal in cultured trypanosomes, causing a block of trans splicing before the first transesterification step. Additionally, CRK9 silencing led to dephosphorylation of RNA polymerase II and to hypomethylation of the SL cap structure. Here, we tandem affinity-purified CRK9 and, among potential CRK9 substrates and modifying enzymes, discovered an unusual tripartite complex comprising CRK9, a new L-type cyclin (CYC12) and a protein, termed CRK9-associated protein (CRK9AP), that is only conserved among kinetoplastids. Silencing of either CYC12 or CRK9AP reproduced the effects of depleting CRK9, identifying these proteins as functional partners of CRK9 in vivo. While mammalian cyclin L binds to CDK11, the CRK9 complex deviates substantially from that of CDK11, requiring CRK9AP for efficient CRK9 complex formation and autophosphorylation in vitro. Interference with this unusual CDK rescued mice from lethal trypanosome infections, validating CRK9 as a potential chemotherapeutic target.

  19. Analysis list: FLI1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available FLI1 Blood,Bone,Muscle + hg19 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/FLI1.1.tsv http:...//dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/FLI1.5.tsv http://dbarchive.biosciencedb...c.jp/kyushu-u/hg19/target/FLI1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/FLI1.Blood.tsv,http:...//dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/FLI1.Bone.tsv,http://dbarchive....biosciencedbc.jp/kyushu-u/hg19/colo/FLI1.Muscle.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/Blood.gml,http:

  20. Experimental study on fly ash capture mercury in flue gas

    Institute of Scientific and Technical Information of China (English)

    Mercedes; DíAZ-SOMOANO; Patricia; ABAD-VALLE; M.Rosa; MARTíNEZ-TARAZONA

    2010-01-01

    Systematic experiments were conducted on a fixed-bed reactor to investigate the interaction between fly ash and mercury,the results implied that fly ash can capture mercury effectively.Among different fly ashes,the unburned carbon in the FA2 and FA3 fly ashes has the highest mercury capture capacity,up to 10.3 and 9.36 μg/g,respectively,which is close to that of commercial activated carbon.There is no obvious relationship between mercury content and carbon content or BET surface area of fly ash.Petrography classification standard was applied to distinguish fly ash carbon particles.Carbon content is not the only variable that controls mercury capture on fly ash,there are likely significant differences in the mercury capture capacities of the various carbon forms.Mercury capture capacity mainly depends on the content of anisotropy carbon particles with porous network structure.