The immune response to sand fly salivary proteins and its influence on Leishmania immunity

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Regis eGomes

2012-05-01

Full Text Available Leishmaniasis is a vector-borne disease transmitted by bites of phlebotomine sand flies. During Leishmania transmission, sand fly saliva is co-inoculated with parasites into the skin of the mammalian host. Sand fly saliva consists of roughly thirty different salivary proteins, many with known roles linked to blood feeding facilitation. Apart from the anti-hemostatic capacity of saliva, several sand fly salivary proteins have been shown to be immunogenic upon multiple contacts with a mammalian host. Immunization with single immunogenic salivary proteins or exposure to uninfected bites can produce protective immune responses against leishmaniasis. These sand fly salivary proteins induce cellular immune responses and/or antibodies. Antibodies to saliva are not required for protection in a mouse model against leishmaniasis. A strong body of evidence points to the role for saliva-specific T cells producing IFN-γ in the form of a delayed-type hypersensitivity reaction at the bite site as the main protective response. Herein, we review immunity to sand fly salivary proteins in the context of its vector-parasite-host combinations and vaccine potential, as well as some recent advances to shed light on the mechanism of how an immune response to sand fly saliva protects against leishmaniasis.

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

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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 < 0.0001). Blood from guinea pig or horse was best to support 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.

Dispersal and memory of sand flies in an endemic area of cutaneous leishmaniasis, southern Brazil.

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Silva, Natália Maria Maciel Guerra; De Melo, Simone Cristina Castanho Sabaini; Massafera, Rubens; Rossi, Robson Marcelo; Silveira, Thaís Gomes Verzignassi; Teodoro, Ueslei

2013-09-01

The dispersal of and the existence of memory in sand flies were measured in a transmission area of cutaneous leishmaniasis, in the municipality of Bandeirantes, Paraná, Brazil. Sand flies were caught in a rural area, with Shannon trap installed in the forest and three Falcão traps installed in a human-inhabited environment (HIE) and three others in an impacted environment presently uninhabited by humans (EUH), from 1800 to 0600 hours. The captured sand flies were marked with yellow, blue, or red fluorescent powder, according to the environments where they were captured. All marked sand flies were released at 0700 hours at a point between the three environments. The recaptures were made with 28 Falcão traps, distributed in the environments from for 10 consecutive days. The sand flies recaptured were examined under a stereomicroscope and later identified. It was concluded that sand flies are able to disperse over an average distance of 73 m, reaching 130 m in 24 h, showing that: 1) the sand flies were attracted with different intensities to each environment, and the ability to move among different environments allows the existence of enzootic cycle of Leishmania; 2) the sand flies possess a spatial memory, olfactory memory, or both, that enable them to return to the environment where they were captured initially, although the distances were different.

Variation in density of cattle-visiting muscid flies between Danish inland pastures

DEFF Research Database (Denmark)

Jensen, Karl-Martin Vagn; Jespersen, Jørgen B.; Nielsen, B. Overgaard

1993-01-01

The density of cattle-visiting flies (Muscidae) and the load of black-flies (Simulium spp.) were estimated in twelve and eighteen inland pastures in Denmark in 1984 and 1985 respectively. No differences in the geographical distribution pattern of the predominant cattle-visiting Muscidae were reco......-exposed pastures. A comparable relationship was found for Haematobia irritans. With Haematobosca stimulans (Mg.) and Morellia spp. no relation between grassland environment and fly density was detected....

Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

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Palaniappan, Jayanthi

2017-04-01

Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

New Records and Updated Checklist of Phlebotomine Sand Flies (Diptera: Psychodidae) From Liberia.

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Obenauer, P J; Rueda, L M; El-Hossary, S S; Watany, N; Stoops, C A; Fakoli, L S; Bolay, F K; Diclaro, J W

2016-05-01

Phlebotomine sand flies from three counties in Liberia were collected from January 2011 to July 2013. In total, 3,118 sand flies were collected: 18 species were identified, 13 of which represented new records for Liberia. An updated taxonomic checklist is provided with a brief note on sand fly biology, and the disease vector potential for species is discussed. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

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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.

Habitat analysis of North American sand flies near veterans returning from leishmania-endemic war zones

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Keep Lisa

2008-12-01

Full Text Available Abstract Background Nearly 1300 cases of leishmaniasis have been identified in American military personnel deployed to Iraq and Afghanistan. The symptoms of this disease can range from a mild, self-limiting cutaneous infection to a deadly visceral infection and are not prevented by chemoprophylaxis or immunization. Effective treatments, however, are available. The disease-causing parasite is spread through the bite of the female sand fly. Although the disease occurs in both the Old World and the New World, the parasite species differ between the hemispheres. The large number of cases in military veterans has caused some concern that Old World, temperate-adapted parasite species could be introduced into the native sand fly populations of American military facilities where veterans of the current conflicts return following their deployments. This paper reports part of a larger study to analyze the risk of such an accidental importation. Four potential habitats on two large Army facilities in the Southeast United States were surveyed to determine relative sand fly density. The National Land Cover Map was used to provide sand fly density prediction maps by habitat. Results Sand fly density was significantly higher in deciduous forest and even higher at the interface between forest and open grassland. The evergreen forest and agricultural fields supported very low densities. On Fort Campbell, KY, the percentage of land covered by suitable habitat was very high. A sand fly density prediction map identified large tracts of land where infected individuals would be at higher risk of exposure to sand fly bites, resulting in an increased risk of introducing the parasite to a native insect population. On Fort Bragg, NC, however, commercial farming of long leaf pine reduced the percentage of the land covered in vegetation suitable for the support of sand flies. The risk of introducing an exotic Leishmania spp. on Fort Bragg, therefore, is considered to be

Recent advances in phlebotomine sand fly research related to leishmaniasis control.

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Bates, Paul A; Depaquit, Jerôme; Galati, Eunice A B; Kamhawi, Shaden; Maroli, Michele; McDowell, Mary Ann; Picado, Albert; Ready, Paul D; Salomón, O Daniel; Shaw, Jeffrey J; Traub-Csekö, Yara M; Warburg, Alon

2015-02-27

Phlebotomine sand flies are the subject of much research because of the role of their females as the only proven natural vectors of Leishmania species, the parasitic protozoans that are the causative agents of the neglected tropical disease leishmaniasis. Activity in this field was highlighted by the eighth International Symposium on Phlebotomine Sand flies (ISOPS) held in September 2014, which prompted this review focusing on vector control. Topics reviewed include: Taxonomy and phylogenetics, Vector competence, Genetics, genomics and transcriptomics, Eco-epidemiology, and Vector control. Research on sand flies as leishmaniasis vectors has revealed a diverse array of zoonotic and anthroponotic transmission cycles, mostly in subtropical and tropical regions of Africa, Asia and Latin America, but also in Mediterranean Europe. The challenge is to progress beyond descriptive eco-epidemiology, in order to separate vectors of biomedical importance from the sand fly species that are competent vectors but lack the vectorial capacity to cause much human disease. Transmission modelling is required to identify the vectors that are a public health priority, the ones that must be controlled as part of the integrated control of leishmaniasis. Effective modelling of transmission will require the use of entomological indices more precise than those usually reported in the leishmaniasis literature.

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

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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.

Ecological and Control Techniques for Sand Flies (Diptera: Psychodidae) Associated with Rodent Reservoirs of Leishmaniasis

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2013-09-12

that cause visceral or dermal leishmaniasis. Unveiling aspects of the life cycles of sand flies that could be targeted with insecticides would guide...leishmaniasis. Unveiling aspects of the life cycles of sand flies that could be targeted with insecticides would guide future sand fly control programs for...to break the transmission cycle of L. major parasites, similar to what Kobylinski et al. described for reducing Plasmodium infection rates in malaria

Molecular Identification of Leishmania spp. in Sand Flies (Diptera: Psychodidae, Phlebotominae) From Ecuador

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Cevallos, Varsovia; Morales, Diego; Baldeón, Manuel E; Cárdenas, Paúl; Rojas-Silva, Patricio; Ponce, Patricio

2017-01-01

Abstract The detection and identification of natural infections in sand flies by Leishmania protozoan species in endemic areas is a key factor in assessing the risk of leishmaniasis and in designing prevention and control measures for this infectious disease. In this study, we analyzed the Leishmania DNA using nuclear ribosomal internal transcript spacer (ITS) sequences. Parasite DNA was extracted from naturally infected, blood-fed sand flies collected in nine localities considered leishmaniasis-endemic foci in Ecuador. The species of parasites identified in sand flies were Leishmania major-like, Leishmania naiffi, Leishmania mexicana, Leishmania lainsoni, and “Leishmania sp. siamensis”. Sand fly specimens of Brumptomyia leopoldoi, Mycropigomyia cayennensis, Nyssomyia yuilli yuilli, Nyssomyia trapidoi, Pressatia triacantha, Pressatia dysponeta, Psychodopygus carrerai carrerai, Psychodopygus panamensis, and Trichophoromyia ubiquitalis were found positive for Leishmania parasite. These findings contribute to a better understanding of the epidemiology and transmission dynamics of the disease in high-risk areas of Ecuador. PMID:28981860

Molecular Identification of Leishmania spp. in Sand Flies (Diptera: Psychodidae, Phlebotominae) From Ecuador.

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Quiroga, Cristina; Cevallos, Varsovia; Morales, Diego; Baldeón, Manuel E; Cárdenas, Paúl; Rojas-Silva, Patricio; Ponce, Patricio

2017-11-07

The detection and identification of natural infections in sand flies by Leishmania protozoan species in endemic areas is a key factor in assessing the risk of leishmaniasis and in designing prevention and control measures for this infectious disease. In this study, we analyzed the Leishmania DNA using nuclear ribosomal internal transcript spacer (ITS) sequences. Parasite DNA was extracted from naturally infected, blood-fed sand flies collected in nine localities considered leishmaniasis-endemic foci in Ecuador.The species of parasites identified in sand flies were Leishmania major-like, Leishmania naiffi, Leishmania mexicana, Leishmania lainsoni, and "Leishmania sp. siamensis". Sand fly specimens of Brumptomyia leopoldoi, Mycropigomyia cayennensis, Nyssomyia yuilli yuilli, Nyssomyia trapidoi, Pressatia triacantha, Pressatia dysponeta, Psychodopygus carrerai carrerai, Psychodopygus panamensis, and Trichophoromyia ubiquitalis were found positive for Leishmania parasite. These findings contribute to a better understanding of the epidemiology and transmission dynamics of the disease in high-risk areas of Ecuador. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

New records of phlebotomine sand flies (Diptera: Psychodidae from Ecuador

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J. Bruce Alexander

1992-03-01

Full Text Available The plebotomine sand fly fauna of Ecuador was surveyed in two 3-month collecting trips made in 1988 and 1990. A total of 12 provinces were visited, including three (Bolivar, Loja and Morona Santiago from wich no previous records to phlebotomines existed. Forty-six species were collected, 13 of wich, together with 1 subspecies and 1 genus (Warileya represented new records for the country. This survey increases the known number of species in Ecuador to 60. The distribuition of Ecuadorian sand flies is discussed in the light of these new findings.

Combining epidemiology with basic biology of sand flies, parasites, and hosts to inform leishmaniasis transmission dynamics and control.

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Courtenay, Orin; Peters, Nathan C; Rogers, Matthew E; Bern, Caryn

2017-10-01

Quantitation of the nonlinear heterogeneities in Leishmania parasites, sand fly vectors, and mammalian host relationships provides insights to better understand leishmanial transmission epidemiology towards improving its control. The parasite manipulates the sand fly via production of promastigote secretory gel (PSG), leading to the "blocked sand fly" phenotype, persistent feeding attempts, and feeding on multiple hosts. PSG is injected into the mammalian host with the parasite and promotes the establishment of infection. Animal models demonstrate that sand flies with the highest parasite loads and percent metacyclic promastigotes transmit more parasites with greater frequency, resulting in higher load infections that are more likely to be both symptomatic and efficient reservoirs. The existence of mammalian and sand fly "super-spreaders" provides a biological basis for the spatial and temporal clustering of clinical leishmanial disease. Sand fly blood-feeding behavior will determine the efficacies of indoor residual spraying, topical insecticides, and bed nets. Interventions need to have sufficient coverage to include transmission hot spots, especially in the absence of field tools to assess infectiousness. Interventions that reduce sand fly densities in the absence of elimination could have negative consequences, for example, by interfering with partial immunity conferred by exposure to sand fly saliva. A deeper understanding of both sand fly and host biology and behavior is essential to ensuring effectiveness of vector interventions.

Variation in density of cattle-visiting muscid flies between Danish inland pastures

DEFF Research Database (Denmark)

Jensen, Karl-Martin Vagn; Jespersen, Jørgen B.; Nielsen, B. Overgaard

1993-01-01

recorded, whilst the relative abundance and density of the species and the total fly-load varied considerably between pastures. In most cases the mean loads of Haematobia irritans (L.) and Hydrotaea irritans (Fall.) on heifers varied significantly in relation to site topography and shelter. These crude......The density of cattle-visiting flies (Muscidae) and the load of black-flies (Simulium spp.) were estimated in twelve and eighteen inland pastures in Denmark in 1984 and 1985 respectively. No differences in the geographical distribution pattern of the predominant cattle-visiting Muscidae were...... site variables explained 65-98% of the variation in densities of horn flies and sheep head flies observed between pastures. Highest densities of Hydrotaea irritans were primarily associated with permanent, low-lying, fairly sheltered grassland sites, whereas the density was low in temporary, dry, wind...

Utilization of fly ash as partial sand replacement in oil palm shell lightweight aggregate concrete

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Nazrin Akmal, A. Z. Muhammad; Muthusamy, K.; Mat Yahaya, F.; Hanafi, H. Mohd; Nur Azzimah, Z.

2017-11-01

Realization on the increasing demand for river sand supply in construction sector has inspired the current research to find alternative material to reduce the use of natural sand in oil palm shell lightweight aggregate concrete (OPS LWAC) production. The existence of fly ash, a by-product generated from coal power plant, which pose negative impact to the environment when it is disposed as waste, were used in this research. The effect of fly ash content as partial sand replacement towards workability and compressive strength of OPS lightweight aggregate concrete were investigated. Four concrete mixes containing various percentage of fly ash that are 0%, 10%, 20% and 30% by weight of sand were used in the experimental work. All mixes were cast in form of cubes before subjected to water curing until the testing age. Compressive strength test were conducted at 1, 3, 7 and 28 days. The finding shows that the workability of the OPS LWAC decreases when more fly ash are used as sand replacement. It was found that adding of 10% fly ash as sand replacement content resulted in better compressive strength of OPS LWAC, which is higher than the control mix.

Insecticide resistance in the sand fly, Phlebotomus papatasi from Khartoum State, Sudan.

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Hassan, Mo'awia Mukhtar; Widaa, Sally Osman; Osman, Osman Mohieldin; Numiary, Mona Siddig Mohammed; Ibrahim, Mihad Abdelaal; Abushama, Hind Mohammed

2012-03-07

Phlebotomus papatasi the vector of cutaneous leishmaniasis (CL) is the most widely spread sand fly in Sudan. No data has previously been collected on insecticide susceptibility and/or resistance of this vector, and a first study to establish a baseline data is reported here. Sand flies were collected from Surogia village, (Khartoum State), Rahad Game Reserve (eastern Sudan) and White Nile area (Central Sudan) using light traps. Sand flies were reared in the Tropical Medicine Research Institute laboratory. The insecticide susceptibility status of first progeny (F1) of P. papatasi of each population was tested using WHO insecticide kits. Also, P. papatasi specimens from Surogia village and Rahad Game Reserve were assayed for activities of enzyme systems involved in insecticide resistance (acetylcholinesterase (AChE), non-specific carboxylesterases (EST), glutathione-S-transferases (GSTs) and cytochrome p450 monooxygenases (Cyt p450). Populations of P. papatasi from White Nile and Rahad Game Reserve were sensitive to dichlorodiphenyltrichloroethane (DDT), permethrin, malathion, and propoxur. However, the P. papatasi population from Surogia village was sensitive to DDT and permethrin but highly resistant to malathion and propoxur. Furthermore, P. papatasi of Surogia village had significantly higher insecticide detoxification enzyme activity than of those of Rahad Game Reserve. The sand fly population in Surogia displayed high AChE activity and only three specimens had elevated levels for EST and GST. The study provided evidence for malathion and propoxur resistance in the sand fly population of Surogia village, which probably resulted from anti-malarial control activities carried out in the area during the past 50 years.

Characteristics of SCC with Fly Ash and Manufactured Sand

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Praveen Kumar, K.; Radhakrishna

2016-09-01

Self compacting concrete (SCC) of M40 grade was designed. The binder in SCC consists of OPC and fly ash in the ratio of 65:35. River sand was replaced by manufactured sand (M-sand) at replacement levels of 20,40,60,80 and 100%. An attempt was made to evaluate the workability and strength characteristics of self compacting concrete with river sand and manufactured sand as fine aggregates. For each replacement level, constant workability was maintained by varying the dosage of superplasticizer. T50 flow time, V Funnel time, V-funnel T5 time as well as compressive, split tensile and flexural strength of SCC were found at each replacement level of M-sand. They were compared to SCC with river sand. Results indicate favourable use of M-sand in preparation of Self Compacting Concrete.

[New records of phlebotomine sand flies (Diptera: Psychodidae) near the Amoya River in Chaparral, Tolima].

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Contreras, María Angélica; Vivero, Rafael José; Bejarano, Eduar Elías; Carrillo, Lina María; Vélez, Iván Darío

2012-06-01

In Colombia, the diversity of phlebotomine sand flies is high, with 162 recorded species, and which include vectors of Leishmania spp. To identify the sand fly species of medically importance in the area of influence from Amoyá River Hydroelectric Project, Colombia. Sand flies were collected with CDC light traps, Shannon traps and sticky traps, from 15 villages in Chaparral County,Tolima. A total of 1,077 adult sand fly specimens were collected. Thirteen species were found in the genus Lutzomyiaand one species in the genus Warileya.Among the Lutzomyia species, three species--Lutzomyia longiflocosa, Lutzomyia columbiana and Lutzomyia nuneztovari--are important for their epidemiological history.Lutzomyia suapiensis was a new record for Colombia, and Warileya rotundipennis was recorded for the first time in Tolima. This study contributed to an increased knowledge of Colombian sand flies in terms of (1) expanding the geographical distribution of members of the subfamily Phlebotominae, (2) gaining estimates of species-richness and species associations in central Colombia, and (3) providing a better understanding of epidemiology of leishmaniasis in the Chaparral area.

Studies in Phlebotomine Sand Flies.

Science.gov (United States)

1982-06-30

Reporte de dos casos de [a ology of a sand fly, P/mlebolomu’,s diabolicuw Hall. in forma anergica difusa. Der matol. Rev. Mex. southwestern -Texas...Contribuiin al estudio de los Phmle- CDC, Veterinary Public Health Notes. USDHEW. bwmwnn de Costa Rica (Diptera, Psychodidae). Tesis. CDC. October. pp. 6- 7...janeiron R. j. 195 pp. the Unrited States (D1)pre ra: Psscfirdidae). j. Ortiz, 1. 1965a. Contribuci~in a! estudio tie los flebor- Partrsirtrl. 30:274-275

Distribution and identification of sand flies naturally infected with Leishmania from the Southeastern Peruvian Amazon.

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Victor Zorrilla

2017-11-01

Full Text Available Cutaneous leishmaniasis (CL is an important health problem in the New World affecting civilian and military populations that are frequently exposed in endemic settings. The Peruvian region of Madre de Dios located near the border with Brazil is one of the most endemic CL regions in South America with more than 4,451 reported cases between 2010 and 2015 according to the Peruvian epidemiology directorate. However, little is known regarding the diversity and distribution of sand fly vectors in this region. In this study, we aimed to characterize the sand fly fauna in this endemic setting and identify sand fly species naturally infected with Leishmania possibly involved in pathogen transmission.Sand fly collections were carried out during 2014 and 2015 in the communities of Flor de Acre, Villa Primavera, Mavila and Arca Pacahuara using CDC light traps and Shannon traps. Collected specimens were identified and non-blood-fed females were selected for Leishmania infection screening using kinetoplastid DNA-PCR (kDNA-PCR and nested Real time PCR for species identification.A total of 10,897 phlebotomines belonging to the genus Lutzomyia (58 species and Brumptomyia (2 species were collected. Our study confirmed the widespread distribution and abundance of Lutzomyia (Trichophoromyia spp. (24%, Lu. whitmani (19.4% and Lu. yucumensis (15.8% in the region. Analysis of Shannon diversity index indicates variability in sand fly composition across sites with Villa Primavera presenting the highest sand fly diversity and abundance. Leishmania screening by kDNA-PCR resulted in 45 positive pools collected from Flor de Acre (34 pools, Mavila (10 pools and Arca Pacahuara (1 pool and included 14 species: Lu. yucumensis, Lu. aragoi, Lu. sallesi, Lu. sherlocki, Lu. shawi, Lu. walkeri, Lu nevesi, Lu. migonei, Lu. davisi, Lu. carrerai, Lu. hirsuta, Lu. (Trichophoromyia spp., Lu. llanosmartinsi and Lu. whitmani. Lutzomyia sherlocki, Lu. walkeri and Lu. llanosmartinsi had the

Distribution and identification of sand flies naturally infected with Leishmania from the Southeastern Peruvian Amazon.

Science.gov (United States)

Zorrilla, Victor; De Los Santos, Maxy B; Espada, Liz; Santos, Rocío Del Pilar; Fernandez, Roberto; Urquia, Albino; Stoops, Craig A; Ballard, Sarah-Blythe; Lescano, Andres G; Vásquez, Gissella M; Valdivia, Hugo O

2017-11-01

Cutaneous leishmaniasis (CL) is an important health problem in the New World affecting civilian and military populations that are frequently exposed in endemic settings. The Peruvian region of Madre de Dios located near the border with Brazil is one of the most endemic CL regions in South America with more than 4,451 reported cases between 2010 and 2015 according to the Peruvian epidemiology directorate. However, little is known regarding the diversity and distribution of sand fly vectors in this region. In this study, we aimed to characterize the sand fly fauna in this endemic setting and identify sand fly species naturally infected with Leishmania possibly involved in pathogen transmission. Sand fly collections were carried out during 2014 and 2015 in the communities of Flor de Acre, Villa Primavera, Mavila and Arca Pacahuara using CDC light traps and Shannon traps. Collected specimens were identified and non-blood-fed females were selected for Leishmania infection screening using kinetoplastid DNA-PCR (kDNA-PCR) and nested Real time PCR for species identification. A total of 10,897 phlebotomines belonging to the genus Lutzomyia (58 species) and Brumptomyia (2 species) were collected. Our study confirmed the widespread distribution and abundance of Lutzomyia (Trichophoromyia) spp. (24%), Lu. whitmani (19.4%) and Lu. yucumensis (15.8%) in the region. Analysis of Shannon diversity index indicates variability in sand fly composition across sites with Villa Primavera presenting the highest sand fly diversity and abundance. Leishmania screening by kDNA-PCR resulted in 45 positive pools collected from Flor de Acre (34 pools), Mavila (10 pools) and Arca Pacahuara (1 pool) and included 14 species: Lu. yucumensis, Lu. aragoi, Lu. sallesi, Lu. sherlocki, Lu. shawi, Lu. walkeri, Lu nevesi, Lu. migonei, Lu. davisi, Lu. carrerai, Lu. hirsuta, Lu. (Trichophoromyia) spp., Lu. llanosmartinsi and Lu. whitmani. Lutzomyia sherlocki, Lu. walkeri and Lu. llanosmartinsi had the

Distribution and identification of sand flies naturally infected with Leishmania from the Southeastern Peruvian Amazon

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Zorrilla, Victor; De Los Santos, Maxy B.; Espada, Liz; Santos, Rocío del Pilar; Fernandez, Roberto; Urquia, Albino; Stoops, Craig A.; Ballard, Sarah-Blythe; Lescano, Andres G.; Vásquez, Gissella M.; Valdivia, Hugo O.

2017-01-01

Background Cutaneous leishmaniasis (CL) is an important health problem in the New World affecting civilian and military populations that are frequently exposed in endemic settings. The Peruvian region of Madre de Dios located near the border with Brazil is one of the most endemic CL regions in South America with more than 4,451 reported cases between 2010 and 2015 according to the Peruvian epidemiology directorate. However, little is known regarding the diversity and distribution of sand fly vectors in this region. In this study, we aimed to characterize the sand fly fauna in this endemic setting and identify sand fly species naturally infected with Leishmania possibly involved in pathogen transmission. Methods Sand fly collections were carried out during 2014 and 2015 in the communities of Flor de Acre, Villa Primavera, Mavila and Arca Pacahuara using CDC light traps and Shannon traps. Collected specimens were identified and non-blood-fed females were selected for Leishmania infection screening using kinetoplastid DNA-PCR (kDNA-PCR) and nested Real time PCR for species identification. Results A total of 10,897 phlebotomines belonging to the genus Lutzomyia (58 species) and Brumptomyia (2 species) were collected. Our study confirmed the widespread distribution and abundance of Lutzomyia (Trichophoromyia) spp. (24%), Lu. whitmani (19.4%) and Lu. yucumensis (15.8%) in the region. Analysis of Shannon diversity index indicates variability in sand fly composition across sites with Villa Primavera presenting the highest sand fly diversity and abundance. Leishmania screening by kDNA-PCR resulted in 45 positive pools collected from Flor de Acre (34 pools), Mavila (10 pools) and Arca Pacahuara (1 pool) and included 14 species: Lu. yucumensis, Lu. aragoi, Lu. sallesi, Lu. sherlocki, Lu. shawi, Lu. walkeri, Lu nevesi, Lu. migonei, Lu. davisi, Lu. carrerai, Lu. hirsuta, Lu. (Trichophoromyia) spp., Lu. llanosmartinsi and Lu. whitmani. Lutzomyia sherlocki, Lu. walkeri and Lu

Experimental studies in Ultrasonic Pulse Velocity of roller compacted concrete pavement containing fly ash and M-sand

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S. Krishna Rao

2016-07-01

Full Text Available This paper presents the experimental investigation results of Ultrasonic Pulse Velocity (UPV tests conducted on roller compacted concrete pavement (RCCP material containing Class F fly ash of as mineral admixture. River sand, M-sand and combination of M-sand and River sand are used as fine aggregate in this experimental work. Three types of fly ash roller compacted concrete mixes are prepared using above three types of fine aggregates and they are designated as Series A (River sand, Series B (manufactured sand and Series C (combination of River sand and M-sand. In each series the fly ash content in place of cement is varied from 0% to 60%. In each series and for different ages of curing (i.e 3, 7, 28 and 90 days forty two cube specimens are cast and tested for compressive strength and UPV. The UPV results of fly ash containing roller compacted concrete pavement (FRCCP show lower values at all ages from 3 days to 90 days in comparison with control mix concrete (0% fly ash in all mixes. However, it is also observed that Series B and C mixes containing fly ash show better results in UPV values, compressive strength and Dynamic Elastic Modulus in comparison to Series A mixes with fly ash. Relationships between compressive strength of FRCCP and UPV and Dynamic Elastic Modulus are proposed for all series mixes. A new empirical equation is proposed to determine the Dynamic Elastic Modulus of FRCCP. Keywords: Compressive strength, Dynamic Elastic Modulus, Fly ash, Roller compacted concrete pavement, Ultrasonic Pulse Velocity

Insecticide resistance in the sand fly, Phlebotomus papatasi from Khartoum State, Sudan

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Hassan Mo'awia

2012-03-01

Full Text Available Abstract Background Phlebotomus papatasi the vector of cutaneous leishmaniasis (CL is the most widely spread sand fly in Sudan. No data has previously been collected on insecticide susceptibility and/or resistance of this vector, and a first study to establish a baseline data is reported here. Methods Sand flies were collected from Surogia village, (Khartoum State, Rahad Game Reserve (eastern Sudan and White Nile area (Central Sudan using light traps. Sand flies were reared in the Tropical Medicine Research Institute laboratory. The insecticide susceptibility status of first progeny (F1 of P. papatasi of each population was tested using WHO insecticide kits. Also, P. papatasi specimens from Surogia village and Rahad Game Reserve were assayed for activities of enzyme systems involved in insecticide resistance (acetylcholinesterase (AChE, non-specific carboxylesterases (EST, glutathione-S-transferases (GSTs and cytochrome p450 monooxygenases (Cyt p450. Results Populations of P. papatasi from White Nile and Rahad Game Reserve were sensitive to dichlorodiphenyltrichloroethane (DDT, permethrin, malathion, and propoxur. However, the P. papatasi population from Surogia village was sensitive to DDT and permethrin but highly resistant to malathion and propoxur. Furthermore, P. papatasi of Surogia village had significantly higher insecticide detoxification enzyme activity than of those of Rahad Game Reserve. The sand fly population in Surogia displayed high AChE activity and only three specimens had elevated levels for EST and GST. Conclusions The study provided evidence for malathion and propoxur resistance in the sand fly population of Surogia village, which probably resulted from anti-malarial control activities carried out in the area during the past 50 years.

Field evaluation of a new light trap for phlebotomine sand flies.

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Gaglio, Gabriella; Napoli, Ettore; Falsone, Luigi; Giannetto, Salvatore; Brianti, Emanuele

2017-10-01

Light traps are one of the most common attractive method for the collection of nocturnal insects. Although light traps are generally referred to as "CDC light traps", different models, equipped with incandescent or UV lamps, have been developed. A new light trap, named Laika trap 3.0, equipped with LED lamps and featured with a light and handy design, has been recently proposed into the market. In this study we tested and compared the capture performances of this new trap with those of a classical light trap model under field conditions. From May to November 2013, a Laika trap and a classical light trap were placed biweekly in an area endemic for sand flies. A total of 256 sand fly specimens, belonging to 3 species (Sergentomyia minuta, Phlebotomus perniciosus, Phlebotomus neglectus) were collected during the study period. The Laika trap captured 126 phlebotomine sand flies: P. perniciosus (n=38); S. minuta (n=88), a similar number of specimens (130) and the same species were captured by classical light trap which collected also 3 specimens of P. neglectus. No significant differences in the capture efficiency at each day of trapping, neither in the number of species or in the sex of sand flies were observed. According to results of this study, the Laika trap may be a valid alternative to classical light trap models especially when handy design and low power consumption are key factors in field studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Early Cretaceous trypanosomatids associated with fossil sand fly larvae in Burmese amber

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George Poinar Jr

2007-08-01

Full Text Available Early Cretaceous flagellates with characters typical of trypanosomatids were found in the gut of sand fly larvae, as well as in surrounding debris, in Burmese amber. This discovery supports a hypothesis in which free-living trypanosomatids could have been acquired by sand fly larvae in their feeding environment and then carried transtadially into the adult stage. At some point in time, specific genera were introduced into vertebrates, thus establishing a dixenous life cycle.

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

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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.

The development of Leishmania turanica in sand flies and competition with L. major.

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Chajbullinova, Alsu; Votypka, Jan; Sadlova, Jovana; Kvapilova, Katerina; Seblova, Veronika; Kreisinger, Jakub; Jirku, Milan; Sanjoba, Chizu; Gantuya, Sambuu; Matsumoto, Yoshitsugu; Volf, Petr

2012-10-02

In Central Asian foci of zoonotic cutaneous leishmaniases, mixed infections of Leishmania turanica and L. major have been found in a reservoir host (the great gerbil, Rhombomys opimus) as well as in the sand fly vector Phlebotomus papatasi, but hybrids between these two Leishmania species have never been reported. In addition, the role of sand fly species other than P. papatasi in L. turanica circulation is not clear. In this work we compared the development of L. turanica in three sand fly species belonging to different subgenera. In addition, we studied experimental co-infections of sand flies by both Leishmania species using GFP transfected L. turanica (MRHO/MN/08/BZ18(GFP+)) and RFP transfected L. major (WHOM/IR/-/173-DsRED(RFP+)). The possibility of Leishmania genetic exchange during the vectorial part of the life cycle was studied using flow cytometry combined with immunofluorescent microscopy. Late-stage infections of L. turanica with frequent colonization of the stomodeal valve were observed in the specific vector P. (Phlebotomus) papatasi and in the permissive vector P. (Adlerius) arabicus. On the other hand, in P. sergenti (the specific vector of L. tropica), L. turanica promatigotes were present only until the defecation of bloodmeal remnants. In their natural vector P. papatasi, L. turanica and L. major developed similarly, and the spatiotemporal dynamics of localization in the sand fly gut was the same for both leishmania species. Fluorescence microscopy in combination with FACS analyses did not detect any L. major / L. turanica hybrids in the experimental co-infection of P. papatasi and P. duboscqi. Our data provide new insight into the development of different leishmania parasite species during a mixed infection in the sand fly gut. Despite the fact that both Leishmania species developed well in P. papatasi and P. duboscqi and did not outcompete each other, no genetic exchange was found. However, the ability of L. turanica to establish late

Comparison of LAMP and PCR for molecular mass screening of sand flies for Leishmania martiniquensis infection.

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Tiwananthagorn, Saruda; Kato, Hirotomo; Yeewa, Ranchana; Muengpan, Amontip; Polseela, Raxsina; Leelayoova, Saovanee

2017-02-01

Leishmaniasis caused by Leishmania martiniquensis infection has been reported in human and domestic animals of Martinique Island, Germany, Switzerland, USA, Myanmar and Thailand. The peculiar clinical features of disseminated cutaneous and visceral forms co-existence render the urgent need of specific diagnostic tool to identify the natural sand fly vectors for effective prevention and control strategies. Loop-mediated isothermal amplification (LAMP) of 18S rRNA gene as well as polymerase chain reaction (PCR) of minicircle kinetoplast DNA gene (PCR-mkDNA) have never been applied to detect L. martiniquensis and L. siamensis in sand fly vectors. The present study was aimed to validate malachite green-LAMP (MG-LAMP) and PCR-mkDNA techniques to detect L. martiniquensis in sand fly vectors, compared with the conventional PCR of internal transcribed spacer 1 (PCR-ITS1). We compared the validity of LAMP of 18S rRNA gene and PCR-mkDNA, to PCR-ITS1 in simulation model of L. martiniquensis infection in Sergentomyia gemmea sand flies. Attributable to the sensitivity and specificity, PCR-mkDNA was consecutively applied to detect L. martiniquensis in 380 female sand fly individuals captured in the newly identified affected region of Lamphun Province, Thailand. Results showed that PCR-mkDNA could detect at least one promastigote per sand fly, which was 10-time superior to LAMP and PCR-ITS1. In addition, PCR-mkDNA was more specific, able to differentiate L. martiniquensis from other viscerotropic Leishmania species, such as L. siamensis, L. (L.) donovani, and L. (L.) infantum. Consecutively, mass screening of L. martiniquensis in 380 female sand fly individuals by PCR-mkDNA was implemented in a new affected area of Thailand where a patient with leishmaniasis/HIV co-infection resides; however Leishmania DNA was undetected. In conclusion, PCR-mkDNA is a promising tool for molecular mass screening of L. martiniquensis infection in outbreak areas where several species of Leishmania

Comparison of LAMP and PCR for molecular mass screening of sand flies for Leishmania martiniquensis infection

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Tiwananthagorn, Saruda; Kato, Hirotomo; Yeewa, Ranchana; Muengpan, Amontip; Polseela, Raxsina; Leelayoova, Saovanee

2017-01-01

BACKGROUND Leishmaniasis caused by Leishmania martiniquensis infection has been reported in human and domestic animals of Martinique Island, Germany, Switzerland, USA, Myanmar and Thailand. The peculiar clinical features of disseminated cutaneous and visceral forms co-existence render the urgent need of specific diagnostic tool to identify the natural sand fly vectors for effective prevention and control strategies. Loop-mediated isothermal amplification (LAMP) of 18S rRNA gene as well as polymerase chain reaction (PCR) of minicircle kinetoplast DNA gene (PCR-mkDNA) have never been applied to detect L. martiniquensis and L. siamensis in sand fly vectors. OBJECTIVE The present study was aimed to validate malachite green-LAMP (MG-LAMP) and PCR-mkDNA techniques to detect L. martiniquensis in sand fly vectors, compared with the conventional PCR of internal transcribed spacer 1 (PCR-ITS1). METHODS We compared the validity of LAMP of 18S rRNA gene and PCR-mkDNA, to PCR-ITS1 in simulation model of L. martiniquensis infection in Sergentomyia gemmea sand flies. Attributable to the sensitivity and specificity, PCR-mkDNA was consecutively applied to detect L. martiniquensis in 380 female sand fly individuals captured in the newly identified affected region of Lamphun Province, Thailand. FINDINGS AND MAIN CONCLUSIONS Results showed that PCR-mkDNA could detect at least one promastigote per sand fly, which was 10-time superior to LAMP and PCR-ITS1. In addition, PCR-mkDNA was more specific, able to differentiate L. martiniquensis from other viscerotropic Leishmania species, such as L. siamensis, L. (L.) donovani, and L. (L.) infantum. Consecutively, mass screening of L. martiniquensis in 380 female sand fly individuals by PCR-mkDNA was implemented in a new affected area of Thailand where a patient with leishmaniasis/HIV co-infection resides; however Leishmania DNA was undetected. In conclusion, PCR-mkDNA is a promising tool for molecular mass screening of L. martiniquensis

The phlebotomine sand flies fauna in Parque Estadual do Rio Doce, Minas Gerais, Brazil.

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de Souza, Cristian Ferreira; Brazil, Reginaldo Peçanha; Bevilacqua, Paula Dias; Andrade Filho, Jose Dilermando

2015-12-02

Phlebotomine sand flies are dipterans of the family Psychodidae. They are very important to veterinary medicine because some species are vectors of infective forms of Leishmania spp., the etiological agents of leishmaniasis. The Parque Estadual do Rio Doce is located in an area with constant reports of cases of leishmaniasis. In order to better understanding the phlebotamine sand fly fauna of the park, the present work was undertaken with the goal of analyzing phlebotomine sand flies collected there, verifying their seasonality and correlating their presence with forest and/or anthropic areas. To analyze the fauna of phlebotomine sand flies, HP-type, model CDC light traps were distributed along the Juquita trail of PERD. Twelve traps were installed between September 2012 and February 2014, and captured specimens were identified to species. A total of 1993 phlebotomine sand flies of 30 species were captured. The most abundant species were Pressatia choti, Psychodopygus davisi and Nyssomyia intermedia. The high number of Nyssomyia intermedia captured drew attention because they are considered one of the vectors of the infective Leishmania braziliensis present at PERD. No seasonality was observed in the occurrence of phlebotomine sand flies captured at PERD. The number of captured specimens of vector species, and the distance of traps from the forest boarder, were negatively correlated, showing that these vectors (Nyssomyia intermedia, Nyssomyia whitmani and Migonemyia migonei) were less common inside the forest area and that attention should be drawn to other potential vector species in the forest. These results can contribute to leishmaniasis prevention strategies directed at the visitors and professionals at or near PERD. The finding of the presence of Leishmania vectors in the park area must be given attention, since disease transmission can threaten people who visit PERD and its surroundings. Therefore, information on the prevention of leishmaniasis needs to be

Reducing Sand Fly Numbers in Leishmania Endemic Regions in Kenya with Insecticide Treated Camouflage Screening

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Current US military operations in deserts face persistent threats from sand flies that transmit human Leishmania. Methods to reduce the risk of human infection from leishmaniasis by reducing the number of sand fly vectors were investigated in Kenya. Bifenthrin treated and un-treated camouflage netti...

Leishmania development in sand flies: parasite-vector interactions overview.

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Dostálová, Anna; Volf, Petr

2012-12-03

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.

Sand flies of Nicaragua: a checklist and reports of new collections

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Russell W Raymond

2010-11-01

Full Text Available Sand flies within the genus Lutzomyia serve as the vectors for all species of the protozoan parasite Leishmania in the New World. In this paper, we present a summary of the 29 species of Lutzomyia and one of Brumptomyia previously reported for Nicaragua and report results of our recent collections of 565 sand flies at eight localities in the country from 2001-2006. Lutzomyia longipalpis was the predominant species collected within the Pacific plains region of western Nicaragua, while Lutzomyia cruciata or Lutzomyia barrettoi majuscula were the species most frequently collected in the central highlands and Atlantic plains regions. The collection of Lutzomyia durani (Vargas & Nájera at San Jacinto in July 2001 is a new record for Nicaragua. Leishmaniasis is endemic to Nicaragua and occurs in three forms: cutaneous, mucocutaneous and visceral leishmaniasis. Cutaneous infections are the most prevalent type of leishmaniasis in Nicaragua and they occur in two different clinical manifestations, typical cutaneous leishmaniasis and atypical cutaneous leishmaniasis, depending on the species of the infecting Leishmania parasite. The distribution of sand flies collected during this study in relation to the geographic distribution of clinical forms of leishmaniasis in the country is also discussed.

Application of RFLP-PCR-Based Identification for Sand Fly Surveillance in an Area Endemic for Kala-Azar in Mymensingh, Bangladesh

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Mohammad Shafiul Alam

2012-01-01

Full Text Available Mymensingh is the most endemic district for kala-azar in Bangladesh. Phlebotomus argentipes remains the only known vector although a number of sand fly species are prevalent in this area. Genotyping of sand flies distributed in a VL endemic area was developed by a PCR and restriction-fragment-length polymorphism (RFLP of 18S rRNA gene of sand fly species. Using the RFLP-PCR analysis with AfaI and HinfI restriction enzymes, P. argentipes, P. papatasi, and Sergentomyia species could be identified. Among 1,055 female sand flies successfully analyzed for the species identification individually, 64.4% flies was classified as Sergentomyia species, whereas 35.6% was identified as P. argentipes and no P. papatasi was found. Although infection of Leishmania within the sand flies was individually examined targeting leishmanial minicircle DNA, none of the 1,055 sand flies examined were positive for Leishmania infection. The RFLP-PCR could be useful tools for taxonomic identification and Leishmania infection monitoring in endemic areas of Bangladesh.

Assessing Insecticide Susceptibility of Laboratory Lutzomyia longipalpis and Phlebotomus papatasi Sand Flies (Diptera: Psychodidae: Phlebotominae).

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Denlinger, David S; Lozano-Fuentes, Saul; Lawyer, Phillip G; Black, William C; Bernhardt, Scott A

2015-09-01

Chemical insecticides are effective for controlling Lutzomyia and Phlebotomus sand fly (Diptera: Psychodidae) vectors of Leishmania parasites. However, repeated use of certain insecticides has led to tolerance and resistance. The objective of this study was to determine lethal concentrations (LCs) and lethal exposure times (LTs) to assess levels of susceptibility of laboratory Lutzomyia longipalpis (Lutz and Nieva) and Phlebotomus papatasi (Scopoli) to 10 insecticides using a modified version of the World Health Organization (WHO) exposure kit assay and Centers for Disease Control and Prevention (CDC) bottle bioassay. Sand flies were exposed to insecticides coated on the interior of 0.5-gallon and 1,000-ml glass bottles. Following exposure, the flies were allowed to recover for 24 h, after which mortality was recorded. From dose-response survival curves for L. longipalpis and P. papatasi generated with the QCal software, LCs causing 50, 90, and 95% mortality were determined for each insecticide. The LCs and LTs from this study will be useful as baseline reference points for future studies using the CDC bottle bioassays to assess insecticide susceptibility of sand fly populations in the field. There is a need for a larger repository of sand fly insecticide susceptibility data from the CDC bottle bioassays, including a range of LCs and LTs for more sand fly species with more insecticides. Such a repository would be a valuable tool for vector management. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Identification of immature stages of phlebotomine sand flies using MALDI-TOF MS and mapping of mass spectra during sand fly life cycle

Czech Academy of Sciences Publication Activity Database

Halada, Petr; Hlaváčková, K.; Dvořák, V.; Volf, P.

2018-01-01

Roč. 93, FEB 2018 (2018), s. 47-56 ISSN 0965-1748 R&D Projects: GA ČR(CZ) GA15-04329S Institutional support: RVO:61388971 Keywords : Phlebotomine sand flies * Larvae * Pupae Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.756, year: 2016

Leishmania attachment in permissive vectors and the role of sand fly midgut proteins in parasite-vector interaction

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Dostálová, Anna

2012-01-01

of PhD. thesis named "Leishmania attachment in permissive vectors and the role of sand fly midgut proteins in parasite-vector interaction", Anna Dostálová, 2011 This thesis focuses on the development of protozoan parasites of the genus Leishmania in their insect vectors, sand flies. It sums up results of three projects I was involved in during my PhD studies. Main emphasis was put on permissive sand fly species that support development of various species of Leishmania. Using a novel method of...

Acoustic signals in the sand fly Lutzomyia (Nyssomyia) intermedia (Diptera: Psychodidae).

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Vigoder, Felipe M; Souza, Nataly A; Peixoto, Alexandre A

2011-05-13

Acoustic signals are part of the courtship of many insects and they often act as species-specific signals that are important in the reproductive isolation of closely related species. Here we report the courtship songs of the sand fly Lutzomyia (Nyssomyia) intermedia, one of the main vectors of cutaneous leishmaniasis in Brazil. Recordings were performed using insects from three localities from Eastern Brazil: Posse and Jacarepaguá in Rio de Janeiro State and Corte de Pedra in Bahia State. The three areas have remnants of the Brazilian Atlantic forest, they are endemic for cutaneous leishmaniasis and L. intermedia is the predominant sand fly species. We observed that during courtship L. intermedia males from all populations produced pulse songs consisting of short trains. No significant differences in song parameters were observed between the males of the three localities. L. intermedia males produce acoustic signals as reported for some other sand flies such as the sibling species of the Lutzomyia longipalpis complex. The lack of differences between the males from the three localities is consistent with previous molecular studies of the period gene carried out in the same populations, reinforcing the idea that L. intermedia is not a species complex in the studied areas and that the three populations are likely to have similar vectorial capacities.

Naturally infected Lutzomyia sand flies in a Leishmania-endemic area of Brazil.

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Carvalho, Gustavo M L; Andrade Filho, Jose D; Falcao, Alda L; Rocha Lima, Ana C V M; Gontijo, Celia M F

2008-06-01

In Brazil, Leishmania transmission involves several species of phlebotomine sand flies that are closely associated with different parasites and reservoirs, giving rise to different transmission cycles. The present study focused on naturally infected phlebotomines originating from Santa Luzia, a municipality near Belo Horizonte, capital of the Brazilian state of Minas Gerais, in which leishmaniasis are endemic. Systematic and non systematic approaches,involving the use of light traps and direct aspiration from resting sites, respectively, were used to collect females and flies. Identification of the captured insects and determination of natural infection by Leishmania spp. were performed using both conventional dissection methods and polymerase chain reaction (PCR). The dissection of 102 sand flies allowed five species of Lutzomyia to be identified, although no flagellate parasite forms were observed.In addition, 211 sand flies were identified, were separated according to species, and were combined into 11 pools of up to 20 individuals each. PCR analyses showed that two of these pools were infected with Leishmania:one pool of Lu. whitmani was infected with Le. (Viannia) spp. and another of Lu. cortelezzii was infected with Le. chagasi. This suggests that Lu. whitmani may be a possible vector of Leishmania in the study area, and more work needs to be performed to assess the role of Lu. cortelezzii as a vector.

Fresh steam-flaked corn in cattle feedlots is an important site for fecal coliform contamination by house flies.

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Ghosh, Anuradha; Zurek, Ludek

2015-03-01

House flies are a common pest at food animal facilities, including cattle feedlots. Previously, house flies were shown to play an important role in the ecology of Escherichia coli O157:H7; house flies in cattle feedlots carried this zoonotic pathogen and were able to contaminate cattle through direct contact and/or by contamination of drinking water and feed. Because house flies aggregate in large numbers on fresh ( # 6 h) steam-flaked corn (FSFC) used in cattle feed, the aim of this study was to assess FSFC in a cattle feedlot as a potentially important site of fecal coliform contamination by house flies. House flies and FSFC samples were collected, homogenized, and processed for culturing of fecal coliforms on membrane fecal coliform agar. Selected isolates were identified by 16S rRNA gene sequencing, and representative isolates from each phylogenetic group were genotyped by pulsed-field gel electrophoresis. Fecal coliforms were undetectable in FSFC shortly (0 h) after flaking; however, in summer, after 4 to 6 h, the concentrations of fecal coliforms ranged from 1.9 × 10(3) to 3.7 × 10(4) CFU/g FSFC (mean, 1.1 ± 3.0 × 10(4) CFU/g). House flies from FSFC carried between 7.6 × 10(2) and 4.1 × 10(6) CFU of fecal coliforms per fly (mean, 6.0 ± 2.3 × 10(5) CFU per fly). Fecal coliforms were represented by E. coli (85.1%), Klebsiella spp. (10.6%), and Citrobacter spp. (4.3%). Pulsed-field gel electrophoresis demonstrated clonal matches of E. coli and Klebsiella spp. between house flies and FSFC. In contrast, in winter and in the absence of house flies, the contamination of corn by fecal coliforms was significantly (∼10-fold) lower. These results indicate that FSFC is an important site for bacterial contamination by flies and possible exchange of E. coli and other bacteria among house flies. Further research is needed to evaluate the potential use of screens or blowers to limit the access of house flies to FSFC and therefore their effectiveness in preventing

Description of Pintomyia (Pifanomyia falcaorum sp. n. (Diptera: Psychodidae: Phlebotominae, a Fossil Sand Fly from Dominican Amber

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Reginaldo Peçanha Brazil

2002-06-01

Full Text Available A new species of sand fly, Pintomyia (Pifanomyia falcaorum is described from an amber originated from the northern mountain range of Dominican Republic. The male sand fly specimen is well preserved and most features used in Phlebotominae taxonomy are seen with remarkable clarity.

Diversity of the bacterial and fungal microflora from the midgut and cuticle of phlebotomine sand flies collected in North-Western Iran.

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Mohammad Akhoundi

Full Text Available BACKGROUND: Phlebotomine sand flies are the vectors of the leishmaniases, parasitic diseases caused by Leishmania spp. Little is known about the prevalence and diversity of sand fly microflora colonizing the midgut or the cuticle. Particularly, there is little information on the fungal diversity. This information is important for development of vector control strategies. METHODOLOGY/PRINCIPAL FINDINGS: FIVE SAND FLY SPECIES: Phlebotomus papatasi, P. sergenti, P. kandelakii, P. perfiliewi and P. halepensis were caught in Bileh Savar and Kaleybar in North-Western Iran that are located in endemic foci of visceral leishmaniasis. A total of 35 specimens were processed. Bacterial and fungal strains were identified by routine microbiological methods. We characterized 39 fungal isolates from the cuticle and/or the midgut. They belong to six different genera including Penicillium (17 isolates, Aspergillus (14, Acremonium (5, Fusarium (1, Geotrichum (1 and Candida (1. We identified 33 Gram-negative bacteria: Serratia marcescens (9 isolates, Enterobacter cloacae (6, Pseudomonas fluorescens (6, Klebsiella ozaenae (4, Acinetobacter sp. (3, Escherichia coli (3, Asaia sp. (1 and Pantoea sp. (1 as well as Gram-positive bacteria Bacillus subtilis (5 and Micrococcus luteus (5 in 10 isolates. CONCLUSION/SIGNIFICANCE: Our study provides new data on the microbiotic diversity of field-collected sand flies and for the first time, evidence of the presence of Asaia sp. in sand flies. We have also found a link between physiological stages (unfed, fresh fed, semi gravid and gravid of sand flies and number of bacteria that they carry. Interestingly Pantoea sp. and Klebsiella ozaenae have been isolated in Old World sand fly species. The presence of latter species on sand fly cuticle and in the female midgut suggests a role for this arthropod in dissemination of these pathogenic bacteria in endemic areas. Further experiments are required to clearly delineate the vectorial

Acoustic signals in the sand fly Lutzomyia (Nyssomyia intermedia (Diptera: Psychodidae

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Peixoto Alexandre A

2011-05-01

Full Text Available Abstract Background Acoustic signals are part of the courtship of many insects and they often act as species-specific signals that are important in the reproductive isolation of closely related species. Here we report the courtship songs of the sand fly Lutzomyia (Nyssomyia intermedia, one of the main vectors of cutaneous leishmaniasis in Brazil. Findings Recordings were performed using insects from three localities from Eastern Brazil: Posse and Jacarepaguá in Rio de Janeiro State and Corte de Pedra in Bahia State. The three areas have remnants of the Brazilian Atlantic forest, they are endemic for cutaneous leishmaniasis and L. intermedia is the predominant sand fly species. We observed that during courtship L. intermedia males from all populations produced pulse songs consisting of short trains. No significant differences in song parameters were observed between the males of the three localities. Conclusions L. intermedia males produce acoustic signals as reported for some other sand flies such as the sibling species of the Lutzomyia longipalpis complex. The lack of differences between the males from the three localities is consistent with previous molecular studies of the period gene carried out in the same populations, reinforcing the idea that L. intermedia is not a species complex in the studied areas and that the three populations are likely to have similar vectorial capacities.

Acoustic signals in the sand fly Lutzomyia (Nyssomyia) intermedia (Diptera: Psychodidae)

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2011-01-01

Background Acoustic signals are part of the courtship of many insects and they often act as species-specific signals that are important in the reproductive isolation of closely related species. Here we report the courtship songs of the sand fly Lutzomyia (Nyssomyia) intermedia, one of the main vectors of cutaneous leishmaniasis in Brazil. Findings Recordings were performed using insects from three localities from Eastern Brazil: Posse and Jacarepaguá in Rio de Janeiro State and Corte de Pedra in Bahia State. The three areas have remnants of the Brazilian Atlantic forest, they are endemic for cutaneous leishmaniasis and L. intermedia is the predominant sand fly species. We observed that during courtship L. intermedia males from all populations produced pulse songs consisting of short trains. No significant differences in song parameters were observed between the males of the three localities. Conclusions L. intermedia males produce acoustic signals as reported for some other sand flies such as the sibling species of the Lutzomyia longipalpis complex. The lack of differences between the males from the three localities is consistent with previous molecular studies of the period gene carried out in the same populations, reinforcing the idea that L. intermedia is not a species complex in the studied areas and that the three populations are likely to have similar vectorial capacities. PMID:21569534

House Flies in the Confined Cattle Environment Carry Non-O157 Shiga Toxin-Producing Escherichia coli.

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Puri-Giri, R; Ghosh, A; Thomson, J L; Zurek, L

2017-05-01

Cattle manure is one of the primary larval developmental habitats of house flies, Musca domestica (L.). Cattle serve as asymptomatic reservoirs of Shiga toxin-producing Escherichia coli (STEC), and bacteria are released into the environment in cattle feces. The USDA-FSIS declared seven STEC serogroups (O157, O26, O45, O103, O145, O121, and O111) as adulterants in beef products. In addition, the serogroup O104 was a culprit of a large outbreak in Germany in 2011. Our study aimed to assess the prevalence of seven non-O157 STEC (O26, O45, O145, O103, O121, O111, and O104) serogroups in adult house flies. Flies (n = 463) were collected from nine feedlots and three dairy farms in six states in the United States and individually processed. This involved a culturing approach with immunomagnetic separation followed by multiplex polymerase chain reactions for detection of individual serogroups and virulence traits. The concentration of bacteria on modified Possé agar ranged between 1.0 × 101 and 7.0 × 107 (mean: 1.5 ± 0.3 × 106) CFU/fly. Out of 463 house flies, 159 (34.3%) carried one or more of six E. coli serogroups of interest. However, STEC was found in 1.5% of house flies from feedlots only. These were E. coli O103 and O104 harboring stx1 and ehxA and E. coli O45 with stx1, eae, and ehxA. This is the first study reporting the isolation of non-O157 STEC in house flies from the confined cattle environment and indicating a potential role of this insect as a vector and reservoir of non-O157 STEC in confined beef cattle. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Sand flies naturally infected by Leishmania (L.) mexicana in the peri-urban area of Chetumal city, Quintana Roo, México.

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Sánchez-García, Laura; Berzunza-Cruz, Miriam; Becker-Fauser, Ingeborg; Rebollar-Téllez, Eduardo A

2010-06-01

The surveillance of prevalent Leishmania sand fly vectors is an important issue for epidemiological studies in populated areas where leishmaniasis is endemic. In this study, we collected sand flies from a peri-urban area in the southeast of Mexico. Natural infection with Leishmania (L.) mexicana was studied by PCR using a Leishmania internal transcribed spacer of the ribosomal RNA gene for amplification. Infected Lutzomyia olmeca olmeca, Lu. shannoni and Lu. cruciata sand flies were collected mainly during the high transmission season (November to March), coinciding with the highest sand fly densities. Additionally, positive specimens of Lu. olmeca olmeca were also captured during July and August. The infected sand flies were from primary forest (subperennial forest) and secondary forest (18-25 years old and 10-15 years old respectively). Sand flies collected with Disney and Shannon traps were the ones found to be infected with L. (L.) mexicana. We conclude that the high-risk period in which L. (L.) mexicana is transmitted in the peri-urban area of Chetumal City is from July to March and that transmission is associated with both the subperennial forest and the secondary forest. 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

Current knowledge of sand fly fauna (Diptera: Psychodidae) of northwestern Yemen and how it relates to leishmaniasis transmission.

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El Sawaf, Bahira M; Kassem, Hala A; Mogalli, Nabil M; El Hossary, Shabaan S; Ramadan, Nadia F

2016-10-01

This report presents the results of the first entomological survey of the sand fly fauna in northwestern Yemen. Sand flies were collected using sticky paper traps and CDC light traps from Hajjah governorate, a cutaneous leishmaniasis focus due to Leishmania tropica. Six Phlebotomus species: P. alexandri, P. arabicus. P. bergeroti, P. orientalis, P. papatasi, P. sergenti and ten Sergentomyia species: S. africana, S. antennata, S. christophersi, S. dolichopa, S. dreyfussi, S. fallax, S. multidens, S. taizi, S. tiberiadis, S. yusafi were identified. P. alexandri was the most predominant Phlebotomus species and P. papatasi was a scarce species. S. fallax was the principal Sergentomyia species and S. dolichopa was the least species encountered. The diversity of the sand fly fauna within and among three altitudinal ranges using Simpson index and Jaccard's diversity coefficient respectively were measured. High species diversity was found in all altitude ranges. There seemed to be more association between sand fly fauna in higher altitudes with fauna from moderate altitudes. Sand fly seasonal activity showed a mono-modal trend in the lowland and a confluent bimodal trend in the highlands. Leishmania DNA could not be detected from 150 Phlebotomus females using PCR-RFLP. A possible zoonotic cutaneous transmission cycle due to Leishmania tropica in northwestern Yemen would involve P. arabicus as the sand fly vector and the rock hyrax as the reservoir host. The vector competence for P. alexandri as a vector of visceral leishmaniasis in Hajjah governorate is discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

[Sand flies (Diptera: Psychodidae) of Guaviare Province, Colombia, with 4 new records for the country].

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Cabrera, Olga Lucía; Mosquera, Laureano; Santamaría, Erika; Ferro, Cristina

2009-03-01

Although cases of leishmaniasis have been reported in the province of Guaviare, Colombia, no entomological studies were included to identify the Lutzomyia sand fly vector species in that area. Lutzomyia species were identified from four townships of Guaviare. Probable vectors were named based on those species involved in transmission in other areas. Sampling was undertaken with CDC light traps suspended at heights between 1.5 m and 9 m. Additional sand flies were collected with Shannon traps and by aspiration of adult flies from daytime resting sites. Sand flies belonging to 37 different species were collected. 35 of them were recorded for the first time in Guaviare Province. Four species were new records for Colombia: Lutzomyia begonae, L. campbelli, L. sericea and L. nematoducta. The most abundant species were L. hirsuta 24.3% (148/610), L. yuilli 15.2% (93/610), L. davisi 10.3% (63/610), followed by L. fartigi, L. carrerai, L. antunesi, L. flaviscutellata and L. olmeca bicolor. Seven of these species of have been associated previously with endemic or epidemic transmission of leishmaniasis.

Phlebotomine sand flies (Diptera, Psychodidae from Rio de Janeiro State, Brazil: species distribution and potential vectors of leishmaniases

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Bruno Moreira Carvalho

2014-03-01

Full Text Available Phlebotomine sand flies (Diptera, Psychodidae from Rio de Janeiro State, Brazil: Species distribution and potential vectors of leishmaniases. Rio de Janeiro State, in Brazil, has endemic areas of both cutaneous and visceral leishmaniases. In these areas, entomologic surveillance actions are highly recommended by Brazil's Ministry of Health. The present work describes the results of sand fly captures performed by the Health Department of Rio de Janeiro State between 2009 and 2011 in several municipalities. An updated species list and distribution of phlebotomine sand flies in the state are provided based on an extensive literature review. Currently, the sand fly fauna of Rio de Janeiro State has 65 species, belonging to the genera Brumptomyia (8 spp. and Lutzomyia (57 spp.. Distribution maps of potential leishmaniases vector species Lutzomyia (Nyssomyia intermedia, L. migonei, L. (N. whitmani, L. (N. flaviscutellata and L. (Lutzomyia longipalpis are provided and their epidemiological importance is discussed.

Bacterial diversity of the American sand fly Lutzomyia intermedia using high-throughput metagenomic sequencing.

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Monteiro, Carolina Cunha; Villegas, Luis Eduardo Martinez; Campolina, Thais Bonifácio; Pires, Ana Clara Machado Araújo; Miranda, Jose Carlos; Pimenta, Paulo Filemon Paolucci; Secundino, Nagila Francinete Costa

2016-08-31

Parasites of the genus Leishmania cause a broad spectrum of diseases, collectively known as leishmaniasis, in humans worldwide. American cutaneous leishmaniasis is a neglected disease transmitted by sand fly vectors including Lutzomyia intermedia, a proven vector. The female sand fly can acquire or deliver Leishmania spp. parasites while feeding on a blood meal, which is required for nutrition, egg development and survival. The microbiota composition and abundance varies by food source, life stages and physiological conditions. The sand fly microbiota can affect parasite life-cycle in the vector. We performed a metagenomic analysis for microbiota composition and abundance in Lu. intermedia, from an endemic area in Brazil. The adult insects were collected using CDC light traps, morphologically identified, carefully sterilized, dissected under a microscope and the females separated into groups according to their physiological condition: (i) absence of blood meal (unfed = UN); (ii) presence of blood meal (blood-fed = BF); and (iii) presence of developed ovaries (gravid = GR). Then, they were processed for metagenomics with Illumina Hiseq Sequencing in order to be sequence analyzed and to obtain the taxonomic profiles of the microbiota. Bacterial metagenomic analysis revealed differences in microbiota composition based upon the distinct physiological stages of the adult insect. Sequence identification revealed two phyla (Proteobacteria and Actinobacteria), 11 families and 15 genera; 87 % of the bacteria were Gram-negative, while only one family and two genera were identified as Gram-positive. The genera Ochrobactrum, Bradyrhizobium and Pseudomonas were found across all of the groups. The metagenomic analysis revealed that the microbiota of the Lu. intermedia female sand flies are distinct under specific physiological conditions and consist of 15 bacterial genera. The Ochrobactrum, Bradyrhizobium and Pseudomonas were the common genera. Our results detailing

Sand fly population dynamics and cutaneous leishmaniasis among soldiers in an Atlantic forest remnant in northeastern Brazil.

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Filipe Dantas-Torres

2017-02-01

Full Text Available Outbreaks of cutaneous leishmaniasis are relatively common among soldiers involved in nocturnal activities in tropical forests. We investigated the population dynamics of sand flies in a military training camp located in a remnant of Atlantic rainforest in northeastern Brazil, where outbreaks of cutaneous leishmaniasis have sporadically been described. From July 2012 to July 2014, light traps were monthly placed in 10 collection sites, being nine sites located near the forest edge and one near a sheep and goat stable. Light traps operated from 5:00 pm to 6:00 am, during four consecutive nights. Leishmania infection in sand flies was assessed using a fast real-time PCR assay. Cases of cutaneous leishmaniasis among soldiers were also investigated. In total, 24,606 sand flies belonging to 25 species were identified. Males (n = 12,683 predominated over females (n = 11,923. Sand flies were present during all months, being more numerous in March (n = 1,691 and April 2013 (n = 3,324. Lutzomyia choti (72.9% was the most abundant species, followed by Lutzomyia longispina (13.8%, Lutzomyia complexa (5.3%, representing together >90% of the sand flies collected. Forty cases of cutaneous leishmaniasis were recorded among soldiers from January 2012 to December 2014. Leishmania isolates were obtained from eight patients and were all characterized as Leishmania braziliensis. Soldiers and anyone overnighting in Atlantic rainforest remnants should adopt preventative measures such as the use of repellents on bare skin or clothes and insecticide-treated tents.

Sand fly population dynamics and cutaneous leishmaniasis among soldiers in an Atlantic forest remnant in northeastern Brazil.

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Dantas-Torres, Filipe; Sales, Kamila Gaudêncio da Silva; Miranda, Débora Elienai de Oliveira; da Silva, Fernando José; Figueredo, Luciana Aguiar; de Melo, Fábio Lopes; de Brito, Maria Edileuza Felinto; Andrade, Maria Sandra; Brandão-Filho, Sinval Pinto

2017-02-01

Outbreaks of cutaneous leishmaniasis are relatively common among soldiers involved in nocturnal activities in tropical forests. We investigated the population dynamics of sand flies in a military training camp located in a remnant of Atlantic rainforest in northeastern Brazil, where outbreaks of cutaneous leishmaniasis have sporadically been described. From July 2012 to July 2014, light traps were monthly placed in 10 collection sites, being nine sites located near the forest edge and one near a sheep and goat stable. Light traps operated from 5:00 pm to 6:00 am, during four consecutive nights. Leishmania infection in sand flies was assessed using a fast real-time PCR assay. Cases of cutaneous leishmaniasis among soldiers were also investigated. In total, 24,606 sand flies belonging to 25 species were identified. Males (n = 12,683) predominated over females (n = 11,923). Sand flies were present during all months, being more numerous in March (n = 1,691) and April 2013 (n = 3,324). Lutzomyia choti (72.9%) was the most abundant species, followed by Lutzomyia longispina (13.8%), Lutzomyia complexa (5.3%), representing together >90% of the sand flies collected. Forty cases of cutaneous leishmaniasis were recorded among soldiers from January 2012 to December 2014. Leishmania isolates were obtained from eight patients and were all characterized as Leishmania braziliensis. Soldiers and anyone overnighting in Atlantic rainforest remnants should adopt preventative measures such as the use of repellents on bare skin or clothes and insecticide-treated tents.

Sand Fly Fauna (Diptera, Pcychodidae, Phlebotominae) in Different Leishmaniasis-Endemic Areas of Ecuador, Surveyed Using a Newly Named Mini-Shannon Trap

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Hashiguchi, Kazue; Velez N., Lenin; Kato, Hirotomo; Criollo F., Hipatia; Romero A., Daniel; Gomez L., Eduardo; Martini R., Luiggi; Zambrano C., Flavio; Calvopina H., Manuel; Caceres G., Abraham; Hashiguchi, Yoshihisa

2014-01-01

To study the sand fly fauna, surveys were performed at four different leishmaniasis-endemic sites in Ecuador from February 2013 to April 2014. A modified and simplified version of the conventional Shannon trap was named “mini-Shannon trap” and put to multiple uses at the different study sites in limited, forested and narrow spaces. The mini-Shannon, CDC light trap and protected human landing method were employed for sand fly collection. The species identification of sand flies was performed mainly based on the morphology of spermathecae and cibarium, after dissection of fresh samples. In this study, therefore, only female samples were used for analysis. A total of 1,480 female sand flies belonging to 25 Lutzomyia species were collected. The number of female sand flies collected was 417 (28.2%) using the mini-Shannon trap, 259 (17.5%) using the CDC light trap and 804 (54.3%) by human landing. The total number of sand flies per trap collected by the different methods was markedly affected by the study site, probably because of the various composition of species at each locality. Furthermore, as an additional study, the attraction of sand flies to mini-Shannon traps powered with LED white-light and LED black-light was investigated preliminarily, together with the CDC light trap and human landing. As a result, a total of 426 sand flies of nine Lutzomyia species, including seven man-biting and two non-biting species, were collected during three capture trials in May and June 2014 in an area endemic for leishmaniasis (La Ventura). The black-light proved relatively superior to the white-light with regard to capture numbers, but no significant statistical difference was observed between the two traps. PMID:25589880

Exposure to Phlebotomus argentipes (Diptera, Psychodidae, Phlebotominae sand flies in rural areas of Bihar, India: the role of housing conditions.

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Paritosh Malaviya

Full Text Available Visceral Leishmaniasis (VL is a vector-borne infectious disease, caused by the protozoan Leishmania donovani, which is transmitted by phlebotomine sand flies. In an earlier study in Bihar, India, we found an association between incidence of VL and housing conditions. In the current study we investigated the influence of housing structure and conditions in and around the house on the indoor abundance of Phlebotomus argentipes, the vector of VL in this area.In each of 50 study villages in Muzaffarpur district, we randomly selected 10 houses. Light traps were installed in each house for one night during three annual peaks of sand fly density over two successive years. Sand flies captured were morphologically identified and segregated by species, sex and feeding status. Data on housing conditions and socio-economic status were also collected. We fitted a linear mixed-effects regression model with log-transformed P. argentipes counts as outcome variable and village as random effect.P. argentipes was found in all but four of the 500 households. There was considerable variability between the years and the seasons. On bivariate analysis, housing structure, dampness of the floor, keeping animals inside, presence of animal dung around the house, and socio-economic status were all significantly associated with sand fly density. Highest sand fly densities were observed in thatched houses. In the multivariate model only the housing structure and socio-economic status remained significant.Better housing conditions are associated with lower sand fly densities, independent of other socio-economic conditions. However, in this area in Bihar even in the better-built houses sand flies are present.

SALO, a novel classical pathway complement inhibitor from saliva of the sand fly Lutzomyia longipalpis

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Viviana P. Ferreira; Vladimir Fazito Vale; Michael K. Pangburn; Maha Abdeladhim; Antonio Ferreira Mendes-Sousa; Iliano V. Coutinho-Abreu; Manoochehr Rasouli; Elizabeth A. Brandt; Claudio Meneses; Kolyvan Ferreira Lima; Ricardo Nascimento Araújo; Marcos Horácio Pereira; Michalis Kotsyfakis; Fabiano Oliveira; Shaden Kamhawi

2016-01-01

Blood-feeding insects inject potent salivary components including complement inhibitors into their host's skin to acquire a blood meal. Sand fly saliva was shown to inhibit the classical pathway of complement; however, the molecular identity of the inhibitor remains unknown. Here, we identified SALO as the classical pathway complement inhibitor. SALO, an 11 kDa protein, has no homology to proteins of any other organism apart from New World sand flies. rSALO anti-complement activity has the sa...

Synanthropy of mosquitoes and sand flies near the Aimorés hydroelectric power plant, Brazil.

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Barata, R A; Ursine, R L; Nunes, F P; Morais, D H; Araújo, H S

2012-12-01

The environmental changes resulting from the construction of hydroelectric dams may affect the fauna of insect vectors and consequently the epidemiology of the diseases they transmit. This work examined the mosquito and sand fly fauna in the area of the Aimorés hydroelectric power plant, analyzing the seasonal distribution and the degree of species synanthropy in different ecotopes. Between November, 2008 and September, 2009, entomological captures were performed with the help of HP light traps in the rural, urban, and forest areas of Aimorés, Ituêta, Resplendor, and Baixo Guandu counties. The fauna proved to be quite diversified. Twenty-two species of mosquitoes and 11 species of sand flies were found. Culex quinquefasciatus was predominant among mosquitoes (76.7%), while Lutzomyia intermedia prevailed among sand flies (34.5%). Some of the captured species have medical interest. Supported by the high degree of synanthropy, those species reinforce the need for epidemiological surveillance. © 2012 The Society for Vector Ecology.

After infection with Leishmania infantum, Golden Hamsters (Mesocricetus auratus) become more attractive to female sand flies (Lutzomyia longipalpis).

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Nevatte, T M; Ward, R D; Sedda, L; Hamilton, J G C

2017-07-21

In Brazil, human and canine visceral leishmaniasis is caused by infection with Leishmania infantum, a Protist parasite transmitted by blood-feeding female Lutzomyia longipalpis sand flies. The objective of this study was to determine if the odour of hamsters, infected with Le. infantum, was more attractive than the odour of the same hamsters, before they were infected. The attractiveness of odour collected from individual hamsters (n = 13), before they were infected, was compared in a longitudinal study, with the attractiveness of the odour of the same hamster in a Y-tube olfactometer bioassay, at a late stage of infection. The odour of six of the golden hamsters was significantly more attractive to 50% of the female sand flies at the end of infection compared to before infection and the odour of four of the golden hamsters was significantly more attractive to 75% of the female sand flies at the end of infection. These results strongly indicate that hamsters infected with Le. infantum become significantly more attractive to a greater proportion of female sand flies as the infection progresses.

Suppressing immature house and stable flies in outdoor calf hutches with sand, gravel, and sawdust bedding.

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Schmidtmann, E T

1991-11-01

Sand, gravel, sawdust, and pine shavings were used as bedding in outdoor calf hutches and compared with straw relative to the density of immature (maggot) house flies, Musca domestica, and stable flies, Stomoxys calcitrans. In 6-wk field trials, average densities of house and stable fly maggots in concrete mix sand ranged from only .3 to 1.6 and 0 to .1 maggots/L, respectively; pea size gravel bedding also strongly suppressed densities from less than .1 to .3 and less than .1 to .1 maggots/L, respectively. These densities represent reductions of 76 to greater than 99% relative to straw bedding, but both sand and gravel compacted and became soiled with calf feces, which resulted in unacceptable bedding sanitation and foul odors. Densities of house and stable fly maggots in pine shavings did not differ from those in straw bedding. Nevertheless, in sawdust bedding, maggot density was limited to averages of 1.4 to 8.3 house and 9.8 to 11.8 stable fly maggots/L; this represented reductions of 45 to 91% relative to straw. In a follow-up trial, house and stable fly maggot densities in sawdust averaged 11.3 and 43.9 maggots/L, respectively, reductions of 77 and 46%. These findings suggest that bedding calf hutches with sawdust during warm weather can be useful as an ecologically sound approach to controlling muscoid fly populations on dairy farms.

Phlebotomine sand flies (Diptera: Psychodidae) associated with the appearance of urban Leishmaniasis in the city of Sincelejo, Colombia.

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Bejarano, Eduar Elías; Uribe, Sandra; Rojas, Winston; Dario Velez, Iván

2002-07-01

Although once associated only with rural areas, the American leishmaniasis vectors now appear to be associated also with urban and suburban areas of the Neotropics. Following the appearance of the first autochthonous visceral and cutaneous leishmaniasis cases in the urban area of the city of Sincelejo, Colombia, a preliminary entomological survey of the sand fly species composition was performed using Shannon and CDC light traps. A total of 486 sand flies representing six Lutzomyia species were collected. L. evansi, L. panamensis and L. gomezi, known vectors of Leishmania spp. were the predominant sand fly species around dwellings. The finding of these species in relation to the appearance of the first cases of leishmaniasis in the city mentioned is discussed.

Study on natural breeding sites of sand flies (Diptera: Phlebotominae) in areas of Leishmania transmission in Colombia.

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Vivero, Rafael José; Torres-Gutierrez, Carolina; Bejarano, Eduar E; Peña, Horacio Cadena; Estrada, Luis Gregorio; Florez, Fernando; Ortega, Edgar; Aparicio, Yamileth; Muskus, Carlos E

2015-02-22

The location of the microhabitats where immature phlebotomine sand flies of the genus Lutzomyia develop is one of the least-known aspects of this group of medically important insects. For this reason strategies of source reduction approach for their control have not been possible in contrast to other insect vectors (such as mosquitoes), because their juvenile stages in terrestrial microhabitats is difficult to detect. Direct examination of soil samples, incubation of substrates and the use of emergence traps were the methods used to identify juvenile stages in 160 soil samples from urban and forest habitats within the foci of Leishmania transmission in Colombia. Immatures collected were identified subsequent from the rearing and emergence of adults using taxonomic keys or the analysis of the mitochondrial marker cytochrome oxidase I. Plant species associated with the natural breeding sites were identified and physicochemical properties of the soils were analyzed. A total of 38 (23.7%) sampling sites were identified as breeding sites, 142 phlebotomine sand flies were identified, belonging to 13 species of the genus Lutzomyia and two of Brumptomyia. The greatest numbers of immature were found within the tabular roots (51 immature sand flies from eight positive sites) and bases of trees (35 immature sand flies from 11 sites). The characterization and presence of the tree species (mainly Ceiba pentadra, Anacardium excelsum, Pseudosamanea guachapale) and the physicochemical properties (relative humidity and carbon/nitrogen ratio) of the soils associated with these breeding sites are significant factors in explaining the diversity and abundance of phlebotomine sand flies. Immature phlebotomine sand flies of the genus Lutzomyia in Colombia can be found in a wide variety of breeding sites rich in organic matter, high relative humidity and are associated with a typical vegetation of each locality. These results provide new perspectives for the study of the ecology of the

Fauna and Monthly Activity of Sand Flies at Zoonotic Cutaneous Leishmanianisis Focus in Qomrooddistrict of Qom Province in 2009

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Farzinnia B

2011-08-01

Full Text Available Background and Objectives: Zoonotic cutaneous leishmaniasis (ZCL is a parasitological disease transmitted by female sand flies. There are several endemic foci of disease in different parts of Iran. The disease is mostly reported from central part of Qom Province including the villages Ghanavat and Qomrood. It is clear that knowledge on sand flies ecologyhas the main role in planning the control of cutaneous leishmaniasis (ZCL. This study was carried out to determinecutaneous leishmaniasis vectors in Gomrood district of Qom provincein 2009. Methods: The present study was a descriptive, cross-sectional one conducted on sand flies (the leishmaiosis vectors. It was carried out in Qomrood area of central district of Qom province during 2009. Sand flies were collected biweekly from indoors (bed rooms, stables, etc. and outdoors-rodent burrows of three villages in Gomrood district, using 180 sticky traps (castor oil coated white paper 20 x 32 cm from the beginning (May to the end (November of the active season. For species identification, sand flies were mounted in Puri’s medium and identified after 24 hours using the keys of Theodor and Mesghali (1964.Results: A total of 10252 adult sand flies (4578 from indoors and 5674 from outdoors were collected and identified during May and November 2009. The following seven species were found in indoors: Phlebotomuspapatasi (86.1%, p. salehi (0/021%, P. sergenti (1/74%, p. caucasicus (1/26%, p. alexandri(0/24%, Sergentomyiasintoni (10/35% and S. theodori(0/26%. The collected species of oudoors were Phlebotomuspapatasi (54/67%, P. sergenti (0/35%, p. alexandri(0/035%, S. sintoni (44/02% S. dentata (0/21% S. clydei (0/19%, S. theodori (0/46% and S. pawlowski (0/05%. The most common sand flies in indoors and outdoors resting places were P. papatasi and S. sintoni. P. salehi was the lowest collected species in Gomrood district. The active peaks of sand flies were observed in late May and late August.The sex ratio

Study on Sand Flies as a Vector(s of Cutaneous Leishmaniasis by Nested PCR in Rural Areas of Damghan District, Semnan Province

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Y. Rasi

2012-01-01

Full Text Available Introduction & Objective: Cutaneous Leishmaniasis is caused by obligatory intracellular parasite of genus Lieshmania. The disease is reported from more than half of Iran's provinces. Various species of sand flies are vector of the disease. Determination of vectors and gaining knowledge about them are important for devising of control program. Materials & Methods: This survey was performed as a cross-sectional study in order to determine the vector(s of cutaneous leishmaniasis in Damghan district during 2008-2009. Sand flies were collected from indoors and outdoors by sticky traps twice in month from April to November. Head and last abdominal segments of the samples were removed and mounted in a drop of Puri’s medium and identified. The rest of the sand flies' bodies was subjected to DNA extraction for molecular detection of Leishmania parasite by Nested PCR using specific primers of minicircle kinetoplast DNAResults: Totally, 6110 sand flies in 8 species were collected. P. papatasi had high density (46.7%. Examination of 280 female sand flies by Nested PCR showed that 28 sand flies (10%include 24 specimens P.papatasi (85.7% and 4 specimens P.caucasicus(14.3%were found naturally infected with L.major. The highest rate of infected sandflies were observed in rodents burrow (42.9%. Maximum rate of sand fly infection was in September (89.3%. Conclusion: With respect to high density of P.papatasi and isolation of L.major from it, this species was the main vector of the disease. Detection of L.major from P.caucasicus shows that this species was the secondary vector in rodent burrow. The highest rate of sand leis infected was in September, so personal protection in this month is very important and necessary. Regarding to the high density of vectors and high infection rate of them taking actions to decrease the sand fly abundance and prevention of human biting are suggested.(Sci J Hamadan Univ Med Sci 2012;18(4:47-52

Phlebotomine sand flies (Diptera: Psychodidae associated with the appearance of urban leishmaniasis in the city of Sincelejo, Colombia

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Eduar Elías Bejarano

2002-07-01

Full Text Available Although once associated only with rural areas, the American leishmaniasis vectors now appear to be associated also with urban and suburban areas of the Neotropics. Following the appearance of the first autochthonous visceral and cutaneous leishmaniasis cases in the urban area of the city of Sincelejo, Colombia, a preliminary entomological survey of the sand fly species composition was performed using Shannon and CDC light traps. A total of 486 sand flies representing six Lutzomyia species were collected. L. evansi, L. panamensis and L. gomezi, known vectors of Leishmania spp. were the predominant sand fly species around dwellings. The finding of these species in relation to the appearance of the first cases of leishmaniasis in the city mentioned is discussed.

Leishmania infantum nicotinamidase is required for late-stage development in its natural sand fly vector, Phlebotomus perniciosus.

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Gazanion, Elodie; Seblova, Veronika; Votypka, Jan; Vergnes, Baptiste; Garcia, Déborah; Volf, Petr; Sereno, Denis

2012-04-01

Leishmania infantum nicotinamidase, encoded by the Lipnc1 gene, converts nicotinamide into nicotinicacid to ensure Nicotinamide–Adenine–Dinucleotide (NAD+) biosynthesis. We were curious to explore the role of this enzyme during L. infantum development in its natural sand fly vector, Phlebotomus perniciosus (Diptera, Phlebotominae), using null mutants with a deleted Lipnc1 gene. The null mutants developed as well as the wild type L. infantum at the early time points post their ingestion within the bloodmeal. In contrast, once the blood meal digestion was completed, the null mutants were unable to develop further and establish late-stage infections. Data highlight the importance of the nicotinamide degradation pathway for Leishmania development in sand flies. They indicate that the endogenous nicotinamidase is essential for Leishmania development in the sand fly after the blood meal has been digested and the remnants defecated.

The First Report of Eustigmaeus Johnstoni (Acari: Stigmaeidae Parasitic Mite of Phlebotominae Sand Flies from Iran

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Mehdi Badakhshan

2013-03-01

Full Text Available Background: Stigmaeids mites have been recorded only on Phlebotominae sand flies up to now. Five species of Eustigmaeus, and three of Stigmaeus were reported on infested sandflies in different country up to the present.Methods: Sand flies collection was done using CDC light trap and sticky paper. The mites were isolated from in­fested specimens, mounted in Puri’s medium and identified using reliable keys.Results: A mite infested Phlebotomus papatasi was observed during a study on sandflies of one of the southern provinces of Iran, near to the Persian Gulf. Several scars resulting from mite attachment were found on abdominal tergites of this female sand fly. The mites were identified as Eustigmaeus johnstoni.Conclusion: This parasitic mite is one of the eyeless species, which has a great distribution over the world, reported from Tunisia, Saudi Arabia, Pakistan, Yemen, Cyprus and Palestine. But, this is the first record of this species from Iran.

Effect of basalt, silica sand and fly ash on the mechanical properties ...

Indian Academy of Sciences (India)

2018-05-17

May 17, 2018 ... For this, we first manufactured binary PCs of epoxy/basalt ... Keywords. Polymer concrete; mechanical strength; mixture design; fly ash; silica sand; basalt. 1. .... To reduce the production cost of PCs, it is necessary to minimize ...

Leishmania major glycosylation mutants require phosphoglycans (lpg2- but not lipophosphoglycan (lpg1- for survival in permissive sand fly vectors.

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Anna Svárovská

2010-01-01

Full Text Available Sand fly species able to support the survival of the protozoan parasite Leishmania have been classified as permissive or specific, based upon their ability to support a wide or limited range of strains and/or species. Studies of a limited number of fly/parasite species combinations have implicated parasite surface molecules in this process and here we provide further evidence in support of this proposal. We investigated the role of lipophosphoglycan (LPG and other phosphoglycans (PGs in sand fly survival, using Leishmania major mutants deficient in LPG (lpg1(-, and the phosphoglycan (PG-deficient mutant lpg2(-. The sand fly species used were the permissive species Phlebotomus perniciosus and P. argentipes, and the specific vector P. duboscqi, a species resistant to L. infantum development.The lpg2(- mutants did not survive well in any of the three sand fly species, suggesting that phosphoglycans and/or other LPG2-dependent molecules are required for parasite development. In vitro, all three L. major lines were equally resistant to proteolytic activity of bovine trypsin, suggesting that sand fly-specific hydrolytic proteases or other factors are the reason for the early lpg2(- parasite killing. The lpg1(- mutants developed late-stage infections in two permissive species, P. perniciosus and P. argentipes, where their infection rates and intensities of infections were comparable to the wild type (WT parasites. In contrast, in P. duboscqi the lpg1(- mutants developed significantly worse than the WT parasites.In combination with previous studies, the data establish clearly that LPG is not required for Leishmania survival in permissive species P. perniciosus and P. argentipes but plays an important role in the specific vector P. duboscqi. With regard to PGs other than LPG, the data prove the importance of LPG2-related molecules for survival of L. major in the three sand fly species tested.

Phlebotomine sand flies in Porteirinha, an area of American visceral leishmaniasis transmission in the State of Minas Gerais, Brazil

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Ricardo Andrade Barata

2004-08-01

Full Text Available A study of the phlebotomine sand fly fauna was carried out in an endemic area of American visceral leishmaniasis (AVL in the municipality of Porteirinha, in the Brazilian state of Minas Gerais. Captures were performed with CDC light traps in 7 districts, 5 days per month, during 2 consecutive years (January 2000 to December 2001. A total of 3240 sand flies were captured and identified. Sixteen species were found, among which 15 belonged to the genus Lutzomyia and one to the genus Brumptomyia. Lutzomyia longipalpis, a proven vector of AVL, was the predominant species (71.85% throughout the time period. The interference of climatic factors (temperature, humidity, and rainfall over the populational dynamics of the sand flies was determined. Statistical analysis of the data showed a significant correlation among the number of phlebotomine sand flies collected, rainfall, and humidity, whereas the effect of temperature was negligible, in that particular region. The amount of collected phlebotomine, the number of human cases, and the prevalence of canine AVL in the districts of Porteirinha are discussed.

Control of sand flies with attractive toxic sugar baits (ATSB) and potential impact on non-target organisms in Morocco.

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Qualls, Whitney A; Müller, Gunter C; Khallaayoune, Khalid; Revay, Edita E; Zhioua, Elyes; Kravchenko, Vasiliy D; Arheart, Kristopher L; Xue, Rui-De; Schlein, Yosef; Hausmann, Axel; Kline, Daniel L; Beier, John C

2015-02-08

The persistence and geographical expansion of leishmaniasis is a major public health problem that requires the development of effective integrated vector management strategies for sand fly control. Moreover, these strategies must be economically and environmentally sustainable approaches that can be modified based on the current knowledge of sand fly vector behavior. The efficacy of using attractive toxic sugar baits (ATSB) for sand fly control and the potential impacts of ATSB on non-target organisms in Morocco was investigated. Sand fly field experiments were conducted in an agricultural area along the flood plain of the Ourika River. Six study sites (600 m x 600 m); three with "sugar rich" (with cactus hedges bearing countless ripe fruits) environments and three with "sugar poor" (green vegetation only suitable for plant tissue feeding) environments were selected to evaluate ATSB, containing the toxin, dinotefuran. ATSB applications were made either with bait stations or sprayed on non-flowering vegetation. Control sites were established in both sugar rich and sugar poor environments. Field studies evaluating feeding on vegetation treated with attractive (non-toxic) sugar baits (ASB) by non-target arthropods were conducted at both sites with red stained ASB applied to non-flowering vegetation, flowering vegetation, or on bait stations. At both the sites, a single application of ATSB either applied to vegetation or bait stations significantly reduced densities of both female and male sand flies (Phlebotomus papatasi and P. sergenti) for the five-week trial period. Sand fly populations were reduced by 82.8% and 76.9% at sugar poor sites having ATSB applied to vegetation or presented as a bait station, respectively and by 78.7% and 83.2%, respectively at sugar rich sites. The potential impact of ATSB on non-targets, if applied on green non-flowering vegetation and bait stations, was low for all non-target groups as only 1% and 0.7% were stained with non-toxic bait

Demonstration of genetic exchange during cyclical development of Leishmania in the sand fly vector.

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Akopyants, Natalia S; Kimblin, Nicola; Secundino, Nagila; Patrick, Rachel; Peters, Nathan; Lawyer, Phillip; Dobson, Deborah E; Beverley, Stephen M; Sacks, David L

2009-04-10

Genetic exchange has not been shown to be a mechanism underlying the extensive diversity of Leishmania parasites. We report here evidence that the invertebrate stages of Leishmania are capable of having a sexual cycle consistent with a meiotic process like that described for African trypanosomes. Hybrid progeny were generated that bore full genomic complements from both parents, but kinetoplast DNA maxicircles from one parent. Mating occurred only in the sand fly vector, and hybrids were transmitted to the mammalian host by sand fly bite. Genetic exchange likely contributes to phenotypic diversity in natural populations, and analysis of hybrid progeny will be useful for positional cloning of the genes controlling traits such as virulence, tissue tropism, and drug resistance.

1 1 2 3 Effect of basalt, silica sand and fly ash on the mechanical ...

Indian Academy of Sciences (India)

21

The purpose of this paper is to manufacture quaternary polymer concretes and ... Keywords: Polymer concrete, Mechanical strength, Mixture design, Fly ash, Silica .... The silica foundry sand used was 101TM from the Silica Sand MFG .... To reduce the production cost of PCs, it is necessary to minimize the epoxy content in.

Diversity patterns, Leishmania DNA detection, and bloodmeal identification of Phlebotominae sand flies in villages in northern Colombia.

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González, Camila; León, Cielo; Paz, Andrea; López, Marla; Molina, Gisell; Toro, Diana; Ortiz, Mario; Cordovez, Juan Manuel; Atencia, María Claudia; Aguilera, Germán; Tovar, Catalina

2018-01-01

Leishmaniases are neglected tropical diseases exhibiting complex transmission cycles due to the number of parasite species circulating, sand fly species acting as vectors and infected mammals, including humans, which are defined in the New World as accidental hosts. However, current transmission scenarios are changing, and the disease is no longer exclusively related to forested areas but urban transmission foci occur, involving some species of domestic animals as suspected reservoirs. The aim of this study was to determine the transmission cycles in urban environments by evaluating sand fly diversity, detection of Leishmania DNA, and bloodmeal sources through intra and peridomestic collections. The study was carried out in Colombia, in 13 municipalities of Cordoba department, implementing a methodology that could be further used for the evaluation of vector-borne diseases in villages or towns. Our sampling design included 24 houses randomly selected in each of 15 villages distributed in 13 municipalities, which were sampled in two seasons in 2015 and 2016. Sand flies were collected using CDC light traps placed in intra and peridomestic habitats. In addition to the morphological identification, molecular identification through DNA barcodes was also performed. A total of 19,743 sand flies were collected and 13,848 of them (10,268 females and 3,580 males) were used in molecular procedures. Circulation of two known parasite species-Leishmania infantum and Leishmania panamensis was confirmed. Blood source analyses showed that sand flies fed on humans, particularly in the case of the known L. infantum vector, P. evansi; further analyses are advised to evaluate the reservoirs involved in parasite transmission. Our sampling design allowed us to evaluate potential transmission cycles on a department scale, by defining suspected vector species, parasite species present in different municipalities and feeding habits.

Ground ULV and thermal fog applications against Phlebotomine sand fly vectors of Leishmania in a hot arid environment in western Kenya

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Phlebotomine sand fly vectors of Leishmania continue to threaten US military operations in Africa, Southwest Asia, and the Middle East. Ultra-low volume (ULV) and/or thermal fog pesticide dispersal are potentially effective against sand flies, but operational guidance is thinly based on mosquito con...

Optimization of fly ash as sand replacement materials (SRM) in cement composites containing coconut fiber

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Nadzri, N. I. M.; Jamaludin, S. B.; Mazlee, M. N.; Jamal, Z. A. Z.

2016-07-01

The need of utilizing industrial and agricultural wastes is very important to maintain sustainability. These wastes are often incorporated with cement composites to improve performances in term of physical and mechanical properties. This study presents the results of the investigation of the response of cement composites containing coconut fiber as reinforcement and fly ash use as substitution of sand at different hardening days. Hardening periods of time (7, 14 and 28 days) were selected to study the properties of cement composites. Optimization result showed that 20 wt. % of fly ash (FA) is a suitable material for sand replacement (SRM). Meanwhile 14 days of hardening period gave highest compressive strength (70.12 MPa) from the cement composite containing 9 wt. % of coconut fiber and fly ash. This strength was comparable with the cement without coconut fiber (74.19 MPa) after 28 days of curing.

Efficacy of Different Sampling Methods of Sand Flies (Diptera: Psychodidae in Endemic Focus of Cutaneous Leishmaniasis in Kashan District, Isfahan Province, Iran.

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Marzieh Hesam-Mohammadi

2014-12-01

Full Text Available The aim of the study was to evaluate and compare the efficiency and practicality of seven trapping methods for adult phlebotominae sand flies. The results of this investigation provide information to determine the species composition and nocturnal activity pattern of different sand fly species.The study was carried out in both plain region (about 5km far from northeast and mountainous region (about 40km far from southwest of Kashan City. Seven traps were selected as sampling methods and sand flies were collected during 5 interval times starting July to September 2011 and from 8:00PM to 6:00AM in outdoors habitats. The traps include: sticky traps (4 papers for 2 hours, Disney trap, Malaise, CDC and CO2 light traps, Shannon traps (black and white nets and animal-baited trap.A total of 1445 sand flies belonging to 15 species of Phlebotomus spp. and five of Sergentomyia spp. were collected. Females and males comprised 44.91% and 55.09% of catches, respectively. Of the collected specimens, Se. sintoni was found to be the most prevalent (37.86% species, while Ph. papatasi, accounted for 31.76% of the sand flies.Disney trap and sticky traps exhibited the most productivity than other traps. In addition, in terms of the efficiency of sampling method, these two trapping methods appeared to be the most productive for both estimating the number of sand flies and the species composition in the study area.

Analysis of salivary gland transcripts of the sand fly Lutzomyia ayacuchensis, a vector of Andean-type cutaneous leishmaniasis

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Kato, Hirotomo; Jochim, Ryan C.; Gomez, Eduardo A.; Uezato, Hiroshi; Mimori, Tatsuyuki; Korenaga, Masataka; Sakurai, Tatsuya; Katakura, Ken; Valenzuela, Jesus G.; Hashiguchi, Yoshihisa

2013-01-01

The saliva of blood sucking insects contains potent pharmacologically active components that assist them in counteracting the host hemostatic and inflammatory systems during blood feeding. In addition, sand fly salivary proteins affect host immunity and have the potential to be a vaccine against Leishmania infection. In the present study, the salivary gland transcripts of Lutzomyia ayacuchensis, a vector of cutaneous leishmaniasis in Ecuadorian and Peruvian Andes, were analyzed by sequencing randomly selected clones of the salivary gland cDNA library of this sand fly. This resulted in the identification of the most abundant transcripts coding for secreted proteins. These proteins were homologous to the salivary molecules present in other sand flies including the RGD-containing peptide, PpSP15/SL1 family protein, yellow-related protein, putative apyrase, antigen 5-related protein, D7 family protein, and 27 kDa salivary protein. Of note, homologues of maxadilan, an active vasodilator abundantly present in saliva of Lutzomyia longipalpis, were not identified. This analysis is the first description of salivary proteins from a sand fly of the subgenus Helcocyrtomyia and from vector of cutaneous leishmaniasis in the New World. The present analysis will provide further insights into the evolution of salivary components in blood sucking arthropods. PMID:23000112

Man-biting sand fly species and natural infection with the Leishmania promastigote in leishmaniasis-endemic areas of Ecuador.

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Gomez, Eduardo A; Kato, Hirotomo; Hashiguchi, Yoshihisa

2014-12-01

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 yuilli, and their topographical and vertical distributions were identified. Among all the sand flies, only 197 (1.09%) flies of four Lutzomyia species, Lu. gomezi, Lu. trapidoi, Lu. tortura and Lu. ayacuchensis, were positive for Leishmania. Endotrypanum, a flagellate parasite not pathogenic to humans, were detected in five Lutzomyia species, Lu. robusta, Lu. hartmanni, Lu. trapidoi, Lu. panamensis and Lu. yuilli yuilli, suggesting wide vector-ranges of Endotrypanum species. These data on the genus Lutzomyia and their natural infections with Leishmania and Endotrypanum will be useful for transmission studies and surveillance of leishmaniasis. Copyright © 2014 Elsevier B.V. All rights reserved.

Sand fly control in Kenya with residual pesticide application on HESCO barriers

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US military operations in hot-arid regions still face significant impacts from mosquito and sand fly vectors of diseases. Personal protective measures (PPM) such as DEET or treated bed nets and clothing can reduce contact with disease vectors and nuisance insects; however, irregular use of PPM coupl...

Exosome Secretion by the Parasitic Protozoan Leishmania within the Sand Fly Midgut

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Vanessa Diniz Atayde

2015-11-01

Full Text Available Despite several studies describing the secretion of exosomes by Leishmania in vitro, observation of their formation and release in vivo has remained a major challenge. Herein, we show that Leishmania constitutively secretes exosomes within the lumen of the sand fly midgut through a mechanism homologous to the mammalian pathway. Through egestion experiments, we demonstrate that Leishmania exosomes are part of the sand fly inoculum and are co-egested with the parasite during the insect’s bite, possibly influencing the host infectious process. Indeed, co-inoculation of mice footpads with L. major plus midgut-isolated or in-vitro-isolated L. major exosomes resulted in a significant increase in footpad swelling. Notably, co-injections produced exacerbated lesions through overinduction of inflammatory cytokines, in particular IL-17a. Our data indicate that Leishmania exosomes are an integral part of the parasite’s infectious life cycle, and we propose to add these vesicles to the repertoire of virulence factors associated with vector-transmitted infections.

Phenology and population dynamics of sand flies in a new focus of visceral leishmaniasis in Eastern Azarbaijan Province, North western of Iran.

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Hazratian, Teimour; Rassi, Yavar; Oshaghi, Mohammad Ali; Yaghoobi-Ershadi, Mohammad Reza; Fallah, Esmael; Shirzadi, Mohammad Reza; Rafizadeh, Sina

2011-08-01

To investigate species composition, density, accumulated degree-day and diversity of sand flies during April to October 2010 in Azarshahr district, a new focus of visceral leishmaniasis in north western Iran. Sand flies were collected using sticky traps biweekly and were stored in 96% ethanol. All specimens were mounted in Puri's medium for species identification using valid keys of sandflies. The density was calculated by the formula: number of specimens/m(2) of sticky traps and number of specimens/number of traps. Degree-day was calculated as follows: (Maximum temperature + Minimum temperature)/2-Minimum threshold. Diversity indices of the collected sand flies within different villages were estimated by the Shannon-weaver formula ( H'=∑i=1sPilog(e)Pi). Totally 5 557 specimens comprising 16 Species (14 Phlebotomus, and 2 Sergentomyia) were indentified. The activity of the species extended from April to October. Common sand-flies in resting places were Phlebotomus papatasi, Phlebotomus sergenti and Phlebotomus mongolensis. The monthly average density was 37.6, 41.1, 40.23, 30.38 and 30.67 for Almalodash, Jaragil, Segaiesh, Amirdizaj and Germezgol villages, respectively. Accumulated degree-day from early January to late May was approximately 289 degree days. The minimum threshold temperature for calculating of accumulated degree-day was 17.32°. According on the Shannon-weaver (H'), diversity of sand flies within area study were estimated as 0.917, 1.867, 1.339, 1.673, and 1.562 in Almalodash, Jaragil, Segaiesh, Amirdizaj and Germezgol villages, respectively. This study is the first detailed research in terms of species composition, density, accumulated degree-day and diversity of sand flies in an endemic focus of visceral leishamaniasis in Azarshahr district. The population dynamics of sand flies in Azarshahr district were greatly affected by climatic factors. According to this study the highest activity of the collected sand fly species occurs at the teritary

Significance of bacteria in oviposition and larval development of the sand fly Lutzomyia longipalpis

Science.gov (United States)

2012-01-01

Background Microbial ecology of phlebotomine sand flies is not well understood although bacteria likely play an important role in the sand fly biology and vector capacity for Leishmania parasites. In this study, we assessed the significance of the microbial community of rabbit feces in oviposition and larval development of Lutzomyia longipalpis as well as bacterial colonization of the gut of freshly emerged flies. Methods Sterile (by autoclaving) and non-sterile (control) rabbit feces were used in the two-choice assay to determine their oviposition attractiveness to sand fly females. Bacteria were identified by amplification and sequencing of the 16S rRNA gene with universal eubacterial primers. Sterile, control (non-sterile), and sterilized and inoculated rabbit feces were used to assess the significance of bacteria in L. longipalpis development. Newly emerged adult flies were surface-sterilized and screened for the bacterial population size and diversity by the culturing approach. The digestive tract of L4 sterile and control larvae was incubated with Phalloidin to visualize muscle tissues and DAPI to visualize nuclei. Results Two-choice behavioural assays revealed a great preference of L. longipalpis to lay eggs on rabbit feces with an active complex bacterial community (control) (85.8 % of eggs) in comparison to that of sterile (autoclaved) rabbit feces (14.2 %). Bioassays demonstrated that L. longipalpis larvae can develop in sterile rabbit feces although development time to adult stage was greatly extended (47 days) and survival of larvae was significantly lower (77.8 %) compared to that of larvae developing in the control rabbit feces (32 days and 91.7 %). Larval survival on sterilized rabbit feces inoculated with the individual bacterial isolates originating from this substrate varied greatly depending on a bacterial strain. Rhizobium radiobacter supported larval development to adult stage into the greatest extent (39 days, 88.0 %) in

Effects of timber harvest on phlebotomine sand flies (Diptera: Psychodidae in a production forest: abundance of species on tree trunks and prevalence of trypanosomatids

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Felipe Arley Costa Pessoa

2007-08-01

Full Text Available The Amazon forest is being exploited for timber production. The harvest removes trees, used by sand flies as resting sites, and decreases the canopy, used as refuges by some hosts. The present study evaluated the impact of the timber harvest, the abundance of sand flies, and their trypanosomatid infection rates before and after selective logging. The study was accomplished in terra-firme production forest in an area of timber harvest, state of Amazonas, Brazil. Sand fly catches were carried out in three areas: one before and after the timber harvest, and two control areas, a nature preservation area and a previously exploited area. The flies were caught by aspiration on tree trunks. Samples of sand flies were dissected for parasitological examination. In the site that suffered a harvest, a larger number of individuals was caught before the selective extraction of timber, showing significant difference in relation to the number of individuals and their flagellate infection rates after the logging. The other two areas did not show differences among their sand fly populations. This fact is suggestive of a fauna sensitive to the environmental alterations associated with selective logging.

Molecular detection of Leishmania parasites and host blood meal identification in wild sand flies from a new endemic rural region, south of Iran.

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Azizi, Kourosh; Askari, Mohammad Bagher; Kalantari, Mohsen; Moemenbellah-Fard, Mohammad Djaefar

Zoonotic Cutaneous Leishmaniosis (ZCL) remains the most crucial vector-borne public health disease particularly in endemic rural parts of Iran. The main aim of this study is to identify wild sand flies (Diptera: Psychodidae), determine their infection rate, and differentiate their host blood meal sources using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Sand fly populations were caught with sticky paper traps from 10 different villages in the county of Darab, Fars province, southern Iran. Following their species identification, they were used in one step PCR to determine their infection with Leishmania spp. parasites. They were then subjected to PCR-RFLP protocol to identify and differentiate their blood meal sources. Two genera of Phlebotomus and Sergentomyia comprising 13 species of sand flies were identified in this region. From a total of 150 parous female sand flies, encompassing 4 different medically important species, 7 specimens (4.7%) including 6 Phlebotomus papatasi and 1 Phlebotomus bergeroti were infected with Leishmania major. Molecular data indicated that about 32% of female sand flies fed on man, while nearly 43% fed on rodent and canine hosts. Molecular detection is an efficient way of differentiating the source of blood meals in female sand flies feeding on different vertebrate hosts. It is suggested that P. papatasi is not highly anthropophagic and appears to be an opportunistic feeder on man. This species is, however, the primary vector of ZCL in this region.

Species composition and relative abundance of sand flies of the genus Lutzomyia (Diptera: Psychodidae) at an endemic focus of visceral leishmaniasis in Colombia.

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Ferro, C; Morrison, A C; Torres, M; Pardo, R; Wilson, M L; Tesh, R B

1995-07-01

Ecological studies on the sand fly Lutzomyia longipalpis (Lutz & Neiva) were conducted during 1990-1993 at a small rural community in Colombia where American visceral leishmaniasis is endemic. Weekly sand fly collections were made from pigpens, houses, and natural resting sites, using hand-held aspirators, sticky (oiled) paper traps, and opossum-baited Disney traps. In total, 263,094 sand flies were collected; L. longipalpis predominated (86.1%), followed by L. trinidadensis (11.0%), L. cayennensis (2.7%), and 8 other Lutzomyia species. The species composition and sex ratio of these sand flies varied among sites and by collection method. L. longipalpis were captured most efficiently by direct aspiration from animal bait. Conversely, sticky paper traps, especially inside houses and at rock resting sites, collected a greater diversity of species, but a lower relative abundance of L. longipalpis.

Molecular detection and identification of Leishmania infection in naturally infected sand flies in a focus of cutaneous leishmaniasis in northern Morocco.

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Es-Sette, Nargys; Ajaoud, Malika; Laamrani-Idrissi, Abderrahman; Mellouki, Fouad; Lemrani, Meryem

2014-07-02

Cutaneous leishmaniasis is an infectious disease caused by various species of the flagellate protozoan Leishmania. During the past 20 years, cutaneous leishmaniasis has emerged as a major public health threat in Morocco. The main objective of this study was to study the occurrence of Leishmania infection in vectors and to identify sand fly blood meal sources in an endemic locality of cutaneous leishmaniasis within Sefrou province, where the vectors of leishmaniasis were still unknown. 2650 sand flies were collected using CDC miniature light traps and identified morphologically. The identified sand flies were tested for Leishmania infection by nested PCR. The source of blood meal of 10 freshly engorged females: 6 Phlebotomus longicuspis and 4 Phlebotomus sergenti, was determined using the Cyt b sequence. The collected sand flies consisted of 10 species, seven of which belonged to the genus Phlebotomus and three to the genus Sergentomyia. The most abundant species was P. longicuspis, accounting for 72% of the total sand flies collected. In females of three P. longicuspis and four P. sergenti, Leishmania infantum and Leishmania tropica DNA was detected, respectively.The source of blood meal of engorged females showed that all sand flies tested fed on humans. We report for the first time the natural infection of P. longicuspis with L. infantum in Morocco. The high frequency of this species in this region, in addition to its anthropophilic character make P. longicuspis the putative vector of L. infantum in this cutaneous leishmaniasis focus where L. tropica is confirmed as the causative agent of the disease and P. sergenti as its vector. The presence of L. infantum, and its presumed vector in this area, makes this a site of high risk of visceral leishmaniasis, mostly because of the proximity of a focus of human and canine visceral leishmaniasis.

Direct multiplex PCR (dmPCR) for the identification of six Phlebotomine sand fly species (Diptera: Psychodidae), including major Leishmania vectors of the Mediterranean

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Sand flies (Diptera: Psychodidae, subfamily Phlebotominae) are haematophagous insects that are known to transmit several anthroponotic and zoonotic diseases. Reliable identification of sand flies at species level is crucial for their surveillance, the detection and spread of their pathogens and the ...

Blood-meal identification in phlebotomine sand flies (Diptera: Psychodidae) from Valle Hermoso, a high prevalence zone for cutaneous leishmaniasis in Ecuador.

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Anaguano, David F; Ponce, Patricio; Baldeón, Manuel E; Santander, Stephanie; Cevallos, Varsovia

2015-12-01

Cutaneous leishmaniasis is a neglected tropical disease transmitted by phlebotomine sand flies of the genus Lutzomyia. In South America, cutaneous leishmaniasis is endemic in the majority of countries. There are no previous reports of phlebotomine sand fly host feeding sources in Ecuador. We identified blood meal sources for phlebotomine sand fly species in Valle Hermoso, a hyper endemic area for leishmaniasis in Ecuador. Phlebotomine sand fly collections were carried out during the dry and rainy seasons. PCR and multiplex PCR were performed from DNA extracted from the abdomens of blood-fed females to specifically identify the avian and mammalian blood meal sources. Avian-blood (77%), mammalian-blood (16%) and mixed avian-mammalian blood (7%) were found in the samples. At the species level, blood from chickens (35.5%), humans (2.8%), cows (2.8%) and dogs (1.9%) was specifically detected. Nyssomyia trapidoi was the most common species of Lutzomyia found that fed on birds. The present results may aid the development of effective strategies to control leishmaniasis in Ecuador. Copyright © 2015 Elsevier B.V. All rights reserved.

Study on phlebotomine sand fly (Diptera: Psychodidae fauna in Belo Horizonte, state of Minas Gerais, Brazil

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Carina Margonari de Souza

2004-12-01

Full Text Available A study on the phlebotomine sand fly fauna in Belo Horizonte city, state of Minas Gerais, Brazil, was carried out. From April 2001 to March 2003, monthly systematic collections were performed in three houses from each of the nine regions of the city, using CDC light traps for four consecutive days. The traps were set into the houses and in peridomestic areas totaling 54 traps. A number of 3871 sand fly specimens of the genera Lutzomyia and Brumptomyia were collected. Sixty eight percent of the specimens were L. longipalpis and 16% L. whitmani, insect vectors of visceral and American cutaneous leishmaniasis, respectively. Environmental factors such as temperature, humidity, and frequency of precipitation suggest that the number of insects increases after rainy periods. During the same period mentioned above, seasonal captures were carried out in parks and green areas of Belo Horizonte, using Shannon trap. A total of 579 phlebotomine sand flies were collected from which 398 (68.7% were females with the predominance of L. whitmani and L. monticola. Those specimens were used for natural infection examination, by polymerase chain reaction. No Leishmania DNA was present in any of the specimens tested.

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

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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

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

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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.

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

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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.

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

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Maha Abdeladhim

Full Text Available 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.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.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.

First report of phlebotomine sand flies (Diptera: Psychodidae) in Kansas and Missouri, and a PCR method to distinguish Lutzomyia shannoni from Lutzomyia vexator.

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Weng, Ju-Lin; Young, Samantha L; Gordon, David M; Claborn, David; Petersen, Christine; Ramalho-Ortigao, Marcelo

2012-11-01

Sand flies Lutzomyia (Psathyromyia) shannoni (Dyar) and Lu. (Helcocyrtomyia) vexator (Coquillet) were collected for the first time in southwest Missouri and southeast Kansas, expanding the known range of these species in North America. Altogether, 680 sand flies (356 males and 324 females) were collected during trapping from May through October 2011 and identified using morphological characters. Of the total sand flies collected, 315 were identified as Lu. shannoni, with 181 individuals (or 26.6% of all sand flies) trapped in Missouri and 134 individuals (or 19.7%) trapped in Kansas. Whereas 358 Lu. vexator were identified from southwest Missouri, only a single specimen was trapped in southeast Kansas. One male Lu. vexator with asymmetric gonostyli was trapped in Missouri. We also developed a polymerase chain reaction protocol to consistently and accurately distinguish Lu. shannoni from Lu. vexator based on presence or absence of a 416 bp fragment from the cytochrome oxidase c subunit 1 gene.

Molecular typing of phlebotomine sand flies in al-madinah and asir regions, Saudi Arabia using PCR–RFLP of 18S

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Abeer A. Al-Dakhil

2017-11-01

Full Text Available Studies on the distribution of sand flies are important for the control of leishmaniasis in endemic and neighboring areas. In the present study polymerase chain reaction (PCR–restriction fragment length polymorphism (RFLP was used to identify the distribution of sand flies in Al-Madinah and Asir Regions of Saudi Arabia using PCR–RFLP of 18S ribosomal RNA gene. Based on the morphological characteristics, the sand flies were differentiated into seven species viz., Phlebotomus papatasi, Phlebotomus sergenti, Phlebotomus bergeroti, Sergentomyia clydei, Sergentomyia antennata, Sergentomyia fallax and Sergentomyia schwetzi. PCR–RFLP of 18S ribosomal RNA (rRNA genes with eight different restriction enzymes resulted in species-specific agarose gel electrophoresis banding patterns. Of the eight restriction enzymes used, not a single restriction enzyme by itself could separate species belonging to the same genera (like P. papatasi and P. sergenti by AseI as well as those belonging to different genera (like P. papatasi and S. clydei by AseI. We therefore conclude that the genetic diversity within sand fly species based on PCR–RFLP technique was nonspecific. Studies are in progress to study the viability of alternate techniques like low-stringency single specific primer polymerase chain reaction which can be used for molecular typing.

Midgut morphological changes and autophagy during metamorphosis in sand flies.

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Malta, Juliana; Heerman, Matthew; Weng, Ju Lin; Fernandes, Kenner M; Martins, Gustavo Ferreira; Ramalho-Ortigão, Marcelo

2017-06-01

During metamorphosis, holometabolous insects undergo significant remodeling of their midgut and become able to cope with changes in dietary requirements between larval and adult stages. At this stage, insects must be able to manage and recycle available food resources in order to develop fully into adults, especially when no nutrients are acquired from the environment. Autophagy has been previously suggested to play a crucial role during metamorphosis of the mosquito. Here, we investigate the overall morphological changes of the midgut of the sand fly during metamorphosis and assess the expression profiles of the autophagy-related genes ATG1, ATG6, and ATG8, which are associated with various steps of the autophagic process. Morphological changes in the midgut start during the fourth larval instar, with epithelial degeneration followed by remodeling via the differentiation of regenerative cells in pre-pupal and pupal stages. The changes in the midgut epithelium are paired with the up-regulation of ATG1, ATG6 and ATG8 during the larva-adult transition. Vein, a putative epidermal growth factor involved in regulating epithelial midgut regeneration, is also up-regulated. Autophagy has further been confirmed in sand flies via the presence of autophagosomes residing within the cytoplasmic compartment of the pupal stages. An understanding of the underlying mechanisms of this process should aid the future management of this neglected tropical vector.

Influence of the Microenvironment in the Transcriptome of Leishmania infantum Promastigotes: Sand Fly versus Culture.

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Pedro J Alcolea

2016-05-01

Full Text Available Zoonotic visceral leishmaniasis is a vector-borne disease caused by Leishmania infantum in the Mediterranean Basin, where domestic dogs and wild canids are the main reservoirs. The promastigote stage replicates and develops within the gut of blood-sucking phlebotomine sand flies. Mature promastigotes are injected in the dermis of the mammalian host and differentiate into the amastigote stage within parasitophorous vacuoles of phagocytic cells. The major vector of L. infantum in Spain is Phlebotomus perniciosus. Promastigotes are routinely axenized and cultured to mimic in vitro the conditions inside the insect gut, which allows for most molecular, cellular, immunological and therapeutical studies otherwise inviable. Culture passages are known to decrease infectivity, which is restored by passage through laboratory animals. The most appropriate source of promastigotes is the gut of the vector host but isolation of the parasite is technically challenging. In fact, this option is not viable unless small samples are sufficient for downstream applications like promastigote cultures and nucleic acid amplification. In this study, in vitro infectivity and differential gene expression have been studied in cultured promastigotes at the stationary phase and in promastigotes isolated from the stomodeal valve of the sand fly P. perniciosus. About 20 ng RNA per sample could be isolated. Each sample contained L. infantum promastigotes from 20 sand flies. RNA was successfully amplified and processed for shotgun genome microarray hybridization analysis. Most differentially regulated genes are involved in regulation of gene expression, intracellular signaling, amino acid metabolism and biosynthesis of surface molecules. Interestingly, meta-analysis by hierarchical clustering supports that up-regulation of 22.4% of the differentially regulated genes is specifically enhanced by the microenvironment (i.e. sand fly gut or culture. The correlation between cultured and

Virulence of a malaria parasite, Plasmodium mexicanum, for its sand fly vectors, Lutzomyia vexator and Lutzomyia stewarti (Diptera: Psychodidae).

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Schall, Jos J

2011-11-01

Evolutionary theory predicts that virulence of parasites for mobile vector insects will be low for natural parasite-host associations that have coevolved. I determined virulence of the malaria parasite of lizards, Plasmodium mexicanum, for its vectors, two species of sand fly (Diptera: Psychodidae), Lutzomyia vexator (Coquillett 1907) and Lutzomyia stewarti (Mangabeira Fo & Galindo 1944), by measuring several life history traits. Developmental rate from egg to eclosion differed for the two species when noninfected. For both sand fly species, developmental rate for each stage (egg to larval hatching, larval period, pupal period) and life span were not altered by infection. Infected sand flies, however, produced fewer eggs. This reduction in fecundity may be a result of lower quality of the blood meal taken from infected lizards (lower concentration of hemoglobin). This report is the first measure of virulence of Plasmodium for an insect vector other than a mosquito and concords with both expectations of theory and previous studies on natural parasite-host associations that revealed low virulence.

First Evidence of a Hybrid of Leishmania (Viannia) braziliensis/L. (V.) peruviana DNA Detected from the Phlebotomine Sand Fly Lutzomyia tejadai in Peru

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Hashiguchi, Yoshihisa

2016-01-01

The natural infection of sand flies by Leishmania was examined in the Department of Huanuco of Peru, where cutaneous leishmaniasis caused by a hybrid of Leishmania (Viannia) braziliensis/L. (V.) peruviana is endemic. A total of 2,997 female sand flies were captured by CDC light traps and Shannon traps, of which 2,931 and 66 flies were identified as Lutzomyia tejadai and Lu fischeri, respectively. Using crude DNA extracted from individual sand flies as a template, Leishmania DNA was detected from one Lu. tejadai. The parasite species was identified as a hybrid of L. (V.) braziliensis/L. (V.) peruviana on the basis of cytochrome b and mannose phosphate isomerase gene analyses. The result suggested that Lu. tejadai is responsible for the transmission of the hybrid Leishmania circulating in this area. PMID:26735142

Rapid and sensitive detection of Bartonella bacilliformis in experimentally infected sand flies by loop-mediated isothermal amplification (LAMP of the Pap31 gene.

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Nasikarn Angkasekwinai

2014-12-01

Full Text Available Carrion' disease, caused by Bartonella bacilliformis, remains truly neglected due to its focal geographical nature. A wide spectrum of clinical manifestations, including asymptomatic bacteremia, and lack of a sensitive diagnostic test can potentially lead to a spread of the disease into non-endemic regions where competent sand fly vectors may be present. A reliable test capable of detecting B. bacilliformis is urgently needed. Our objective is to develop a loop-mediated isothermal amplification (LAMP assay targeting the pap31 gene to detect B. bacilliformis.The sensitivity of the LAMP was evaluated in comparison to qPCR using plasmid DNA containing the target gene and genomic DNA in the absence and presence of human or sand fly DNA. The detection limit of LAMP was 1 to 10 copies/µL, depending on the sample metrics. No cross-reaction was observed when testing against a panel of various closely related bacteria. The utility of the LAMP was further compared to qPCR by the examination of 74 Lutzomyia longipalpis sand flies artificially fed on blood spiked with B. bacilliformis and harvested at days (D 1, 3, 5, 7 and 9 post feeding. Only 86% of sand flies at D1 and 63% of flies at D3 were positive by qPCR. LAMP was able to detect B. bacilliformis in all those flies confirmed positive by qPCR. However, none of the flies after D3 were positive by either LAMP or qPCR. In addition to demonstrating the sensitivity of the LAMP assay, these results suggest that B. bacilliformis cannot propagate in artificially fed L. longipalpis.The LAMP assay is as sensitive as qPCR for the detection of B. bacilliformis and could be useful to support diagnosis of patients in low-resource settings and also to identify B. bacilliformis in the sand fly vector.

Repellency and other biological effects of natural substances against the sand fly, Phlebotomus papatasi

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Leishmaniasis is an insect-borne disease caused by several protozoan species in the genus Leishmania, vectored by sand fly species in the genera Phlebotomus, Lutzomyia or others, with different species affecting different geographic ranges. Phlebotomus papatasi (Scopoli) is a major vector of Leishma...

Studies on the sand fly fauna (Diptera: Psychodidae) in high-transmission areas of cutaneous leishmaniasis in the Republic of Suriname

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2013-01-01

Background Sand flies (Diptera: Psychodidae) are the vectors of Leishmania parasites, the causative agents of leishmaniasis. Cutaneous leishmaniasis is an increasing public health problem in the Republic of Suriname and is mainly caused by Leishmania (Vianna) guyanensis, but L. (V.) braziliensis, L. (L.) amazonensis, and L. (V.) naiffi also infect humans. Transmission occurs predominantly in the forested hinterland of the country. Information regarding the potential vectors of leishmaniasis in Suriname is limited. This study aims to broaden the knowledge about vectors involved in the transmission of cutaneous leishmaniasis in Suriname. For this purpose, sand flies were characterized in various foci of cutaneous leishmaniasis in the country, the districts of Para, Brokopondo, and Sipaliwini. Methods Sand flies were collected in areas around mining plots and villages using CDC light traps in the period between February 2011 and March 2013. They were categorized by examination of the spermathecea (females) and the external genitalia (males). Results A total of 2,743 sand fly specimens belonging to 34 different species were captured, including four species (Lutzomyia aragaoi, Lu. ayrozai, Lu. damascenoi, and Lu. sordellii) that had never before been described for Suriname. Five percent of the catch comprised Lu. squamiventris sensu lato, one female of which was positive with L. (V.) braziliensis and was captured in a gold mining area in Brokopondo. Other sand fly species found positive for Leishmania parasites were Lu. trichopyga, Lu. ininii, and Lu. umbratilis, comprising 32, 8, and 4%, respectively, of the catch. These were captured at gold mining areas in Brokopondo and Sipaliwini, but the Leishmania parasites they had ingested could not be identified due to insufficient amounts of DNA. Conclusions The sand fly fauna in Suriname is highly diverse and comprises Lutzomyia species capable of transmitting Leishmania parasites. Four new Lutzomyia species have been found

Seasonal Dynamics of Phlebotomine Sand Fly Species Proven Vectors of Mediterranean Leishmaniasis Caused by Leishmania infantum.

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Bulent Alten

2016-02-01

Full Text Available The recent geographical expansion of phlebotomine vectors of Leishmania infantum in the Mediterranean subregion has been attributed to ongoing climate changes. At these latitudes, the activity of sand flies is typically seasonal; because seasonal phenomena are also sensitive to general variations in climate, current phenological data sets can provide a baseline for continuing investigations on sand fly population dynamics that may impact on future scenarios of leishmaniasis transmission. With this aim, in 2011-2013 a consortium of partners from eight Mediterranean countries carried out entomological investigations in sites where L. infantum transmission was recently reported.A common protocol for sand fly collection included monthly captures by CDC light traps, complemented by sticky traps in most of the sites. Collections were replicated for more than one season in order to reduce the effects of local weather events. In each site, the trapping effort was left unchanged throughout the survey to legitimate inter-seasonal comparisons. Data from 99,000 collected specimens were analyzed, resulting in the description of seasonal dynamics of 56,000 sand flies belonging to L. infantum vector species throughout a wide geographical area, namely P. perniciosus (Portugal, Spain and Italy, P. ariasi (France, P. neglectus (Greece, P. tobbi (Cyprus and Turkey, P. balcanicus and P. kandelakii (Georgia. Time of sand fly appearance/disappearance in collections differed between sites, and seasonal densities showed variations in each site. Significant correlations were found between latitude/mean annual temperature of sites and i the first month of sand fly appearance, that ranged from early April to the first half of June; ii the type of density trend, varying from a single peak in July/August to multiple peaks increasing in magnitude from May through September. A 3-modal trend, recorded for P. tobbi in Cyprus, represents a novel finding for a L. infantum vector

Seasonal Dynamics of Phlebotomine Sand Fly Species Proven Vectors of Mediterranean Leishmaniasis Caused by Leishmania infantum.

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Alten, Bulent; Maia, Carla; Afonso, Maria Odete; Campino, Lenea; Jiménez, Maribel; González, Estela; Molina, Ricardo; Bañuls, Anne Laure; Prudhomme, Jorian; Vergnes, Baptiste; Toty, Celine; Cassan, Cécile; Rahola, Nil; Thierry, Magali; Sereno, Denis; Bongiorno, Gioia; Bianchi, Riccardo; Khoury, Cristina; Tsirigotakis, Nikolaos; Dokianakis, Emmanouil; Antoniou, Maria; Christodoulou, Vasiliki; Mazeris, Apostolos; Karakus, Mehmet; Ozbel, Yusuf; Arserim, Suha K; Erisoz Kasap, Ozge; Gunay, Filiz; Oguz, Gizem; Kaynas, Sinan; Tsertsvadze, Nikoloz; Tskhvaradze, Lamzira; Giorgobiani, Ekaterina; Gramiccia, Marina; Volf, Petr; Gradoni, Luigi

2016-02-01

The recent geographical expansion of phlebotomine vectors of Leishmania infantum in the Mediterranean subregion has been attributed to ongoing climate changes. At these latitudes, the activity of sand flies is typically seasonal; because seasonal phenomena are also sensitive to general variations in climate, current phenological data sets can provide a baseline for continuing investigations on sand fly population dynamics that may impact on future scenarios of leishmaniasis transmission. With this aim, in 2011-2013 a consortium of partners from eight Mediterranean countries carried out entomological investigations in sites where L. infantum transmission was recently reported. A common protocol for sand fly collection included monthly captures by CDC light traps, complemented by sticky traps in most of the sites. Collections were replicated for more than one season in order to reduce the effects of local weather events. In each site, the trapping effort was left unchanged throughout the survey to legitimate inter-seasonal comparisons. Data from 99,000 collected specimens were analyzed, resulting in the description of seasonal dynamics of 56,000 sand flies belonging to L. infantum vector species throughout a wide geographical area, namely P. perniciosus (Portugal, Spain and Italy), P. ariasi (France), P. neglectus (Greece), P. tobbi (Cyprus and Turkey), P. balcanicus and P. kandelakii (Georgia). Time of sand fly appearance/disappearance in collections differed between sites, and seasonal densities showed variations in each site. Significant correlations were found between latitude/mean annual temperature of sites and i) the first month of sand fly appearance, that ranged from early April to the first half of June; ii) the type of density trend, varying from a single peak in July/August to multiple peaks increasing in magnitude from May through September. A 3-modal trend, recorded for P. tobbi in Cyprus, represents a novel finding for a L. infantum vector. Adults

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

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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...

Visualisation of Leishmania donovani fluorescent hybrids during early stage development in the sand fly vector.

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Sadlova, Jovana; Yeo, Matthew; Seblova, Veronika; Lewis, Michael D; Mauricio, Isabel; Volf, Petr; Miles, Michael A

2011-01-01

The Leishmania protozoan parasites cause devastating human diseases. Leishmania have been considered to replicate clonally, without genetic exchange. However, an accumulation of evidence indicates that there are inter-specific and intra-specific hybrids among natural populations. The first and so far only experimental proof of genetic exchange was obtained in 2009 when double drug resistant Leishmania major hybrids were produced by co-infecting sand flies with two strains carrying different drug resistance markers. However, the location and timing of hybridisation events in sand flies has not been described. Here we have co-infected Phlebotomus perniciosus and Lutzomyia longipalpis with transgenic promastigotes of Leishmania donovani strains carrying hygromycin or neomycin resistance genes and red or green fluorescent markers. Fed females were dissected at different times post bloodmeal (PBM) and examined by fluorescent microscopy or fluorescent activated cell sorting (FACS) followed by confocal microscopy. In mixed infections strains LEM3804 and Gebre-1 reached the cardia and stomodeal valves more rapidly than strains LEM4265 and LV9. Hybrids unequivocally expressing both red and green fluorescence were seen in single flies of both vectors tested, co-infected with LEM4265 and Gebre-1. The hybrids were present as short (procyclic) promastigotes 2 days PBM in the semi-digested blood in the endoperitrophic space. Recovery of a clearly co-expressing hybrid was also achieved by FACS. However, hybrids could not sustain growth in vitro. For the first time, we observed L. donovani hybrids in the sand fly vector, 2 days PBM and described the morphological stages involved. Fluorescence microscopy in combination with FACS allows visualisation and recovery of the progeny of experimental crosses but on this occasion the hybrids were not viable in vitro. Nevertheless, genetic exchange in L. donovani has profound epidemiological significance, because it facilitates the emergence

Interleukin 10–Dominant Immune Response and Increased Risk of Cutaneous Leishmaniasis After Natural Exposure to Lutzomyia intermedia Sand Flies

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Carvalho, Augusto M.; Cristal, Juqueline R.; Muniz, Aline C.; Carvalho, Lucas P.; Gomes, Regis; Miranda, José C.; Barral, Aldina; Carvalho, Edgar M.; de Oliveira, Camila I.

2015-01-01

Background. Leishmaniasis is caused by parasites transmitted to the vertebrate host by infected sand flies. During transmission, the vertebrate host is also inoculated with sand fly saliva, which exerts powerful immunomodulatory effects on the host's immune response. Methods. We conducted a prospective cohort analysis to characterize the human immune response to Lutzomyia intermedia saliva in 264 individuals, from an area for cutaneous leishmaniasis (CL) caused by Leishmania braziliensis. Results. Antibodies were found in 150 individuals (56.8%); immunoglobulin G1 and G4 were the predominant subclasses. Recall responses to salivary gland sonicate showed elevated production of interleukin 10 (IL-10), interleukin 13, interferon γ, CXCL9, and CCL2 compared with controls. CD4+CD25+ T cells, including Foxp3+ cells, were the main source of IL-10. L. braziliensis replication was increased (P intermedia sand flies skews the human immune response, facilitating L. braziliensis survival in vitro, and increases the risk of developing CL. PMID:25596303

DNA barcode for the identification of the sand fly Lutzomyia longipalpis plant feeding preferences in a tropical urban environment.

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Lima, Leonardo H G de M; Mesquita, Marcelo R; Skrip, Laura; de Souza Freitas, Moisés T; Silva, Vladimir C; Kirstein, Oscar D; Abassi, Ibrahim; Warburg, Alon; Balbino, Valdir de Q; Costa, Carlos H N

2016-07-20

Little is known about the feeding behavior of hematophagous insects that require plant sugar to complete their life cycles. We studied plant feeding of Lutzomyia longipalpis sand flies, known vectors of Leishmania infantum/chagasi parasites, in a Brazilian city endemic with visceral leishmaniasis. The DNA barcode technique was applied to identify plant food source of wild-caught L. longipalpis using specific primers for a locus from the chloroplast genome, ribulose diphosphate carboxylase. DNA from all trees or shrubs within a 100-meter radius from the trap were collected to build a barcode reference library. While plants from the Anacardiaceae and Meliaceae families were the most abundant at the sampling site (25.4% and 12.7% of the local plant population, respectively), DNA from these plant families was found in few flies; in contrast, despite its low abundance (2.9%), DNA from the Fabaceae family was detected in 94.7% of the sand flies. The proportion of sand flies testing positive for DNA from a given plant family was not significantly associated with abundance, distance from the trap, or average crown expansion of plants from that family. The data suggest that there may indeed be a feeding preference of L. longipalpis for plants in the Fabaceae family.

The midgut transcriptome of Phlebotomus (Larroussius) perniciosus, a vector of Leishmania infantum: comparison of sugar fed and blood fed sand flies.

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Dostálová, Anna; Votýpka, Jan; Favreau, Amanda J; Barbian, Kent D; Volf, Petr; Valenzuela, Jesus G; Jochim, Ryan C

2011-05-10

Parasite-vector interactions are fundamental in the transmission of vector-borne diseases such as leishmaniasis. Leishmania development in the vector sand fly is confined to the digestive tract, where sand fly midgut molecules interact with the parasites. In this work we sequenced and analyzed two midgut-specific cDNA libraries from sugar fed and blood fed female Phlebotomus perniciosus and compared the transcript expression profiles. A total of 4111 high quality sequences were obtained from the two libraries and assembled into 370 contigs and 1085 singletons. Molecules with putative roles in blood meal digestion, peritrophic matrix formation, immunity and response to oxidative stress were identified, including proteins that were not previously reported in sand flies. These molecules were evaluated relative to other published sand fly transcripts. Comparative analysis of the two libraries revealed transcripts differentially expressed in response to blood feeding. Molecules up regulated by blood feeding include a putative peritrophin (PperPer1), two chymotrypsin-like proteins (PperChym1 and PperChym2), a putative trypsin (PperTryp3) and four putative microvillar proteins (PperMVP1, 2, 4 and 5). Additionally, several transcripts were more abundant in the sugar fed midgut, such as two putative trypsins (PperTryp1 and PperTryp2), a chymotrypsin (PperChym3) and a microvillar protein (PperMVP3). We performed a detailed temporal expression profile analysis of the putative trypsin transcripts using qPCR and confirmed the expression of blood-induced and blood-repressed trypsins. Trypsin expression was measured in Leishmania infantum-infected and uninfected sand flies, which identified the L. infantum-induced down regulation of PperTryp3 at 24 hours post-blood meal. This midgut tissue-specific transcriptome provides insight into the molecules expressed in the midgut of P. perniciosus, an important vector of visceral leishmaniasis in the Old World. Through the comparative

Stage-specific adhesion of Leishmania promastigotes to sand fly midguts assessed using an improved comparative binding assay.

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Raymond Wilson

2010-09-01

Full Text Available The binding of Leishmania promastigotes to the midgut epithelium is regarded as an essential part of the life-cycle in the sand fly vector, enabling the parasites to persist beyond the initial blood meal phase and establish the infection. However, the precise nature of the promastigote stage(s that mediate binding is not fully understood.To address this issue we have developed an in vitro gut binding assay in which two promastigote populations are labelled with different fluorescent dyes and compete for binding to dissected sand fly midguts. Binding of procyclic, nectomonad, leptomonad and metacyclic promastigotes of Leishmania infantum and L. mexicana to the midguts of blood-fed, female Lutzomyia longipalpis was investigated. The results show that procyclic and metacyclic promastigotes do not bind to the midgut epithelium in significant numbers, whereas nectomonad and leptomonad promastigotes both bind strongly and in similar numbers. The assay was then used to compare the binding of a range of different parasite species (L. infantum, L. mexicana, L. braziliensis, L. major, L. tropica to guts dissected from various sand flies (Lu. longipalpis, Phlebotomus papatasi, P. sergenti. The results of these comparisons were in many cases in line with expectations, the natural parasite binding most effectively to its natural vector, and no examples were found where a parasite was unable to bind to its natural vector. However, there were interesting exceptions: L. major and L. tropica being able to bind to Lu. longipalpis better than L. infantum; L. braziliensis was able to bind to P. papatasi as well as L. major; and significant binding of L. major to P. sergenti and L. tropica to P. papatasi was observed.The results demonstrate that Leishmania gut binding is strictly stage-dependent, is a property of those forms found in the middle phase of development (nectomonad and leptomonad forms, but is absent in the early blood meal and final stages (procyclic

Study of phlebotomine sand flies (Diptera: Psychodidae) collected in a Leishmania-endemic area of the metropolitan region of Belo Horizonte, Brazil.

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Carvalho, Gustavo M L; Gontijo, Célia M F; Falcão, Alda L; Andrade Filho, José D

2010-11-01

Phlebotomine sand flies are distributed across nearly all faunal regions of the world, represented by over 800 species, of which many are important vectors of human pathogens. Brazil is currently faced with the expansion and urbanization of leishmaniases, with an increase in the numbers of human cases and seropositive dogs in various medium-sized to large cities. The objective of the current study was to survey the phlebotomine sand fly species in an area endemic for American cutaneous leishmaniasis (ACL) and American visceral leishmaniasis (AVL), i.e., the municipal district of Santa Luzia, lying within the metropolitan region of Belo Horizonte in the Brazilian State of Minas Gerais. Sand flies were collected monthly in 2004-2005 using modified Falcão light traps hung in the peridomiciles of houses and surrounding wooded areas in the district of Baronesa. A total of 1,552 sand flies belonging to seven species was collected, and an interesting pattern of the distribution of the most abundant species relative to the sampling locality was revealed. In the wooded areas Lutzomyia whitmani (Antunes & Coutinho) predominated, whereas in the urban area Lutzomyia longipalpis (Lutz & Neiva) was the most abundant species. These results indicate two possible epidemiological patterns of Leishmania transmission in Santa Luzia: one for American cutaneous leishmaniasis associated predominantly with wooded areas, and another for AVL, with transmission principally occurring around human habitations.

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

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

2003-07-01

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

Development of a loop-mediated isothermal amplification method for rapid mass-screening of sand flies for Leishmania infection.

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Nzelu, Chukwunonso O; Gomez, Eduardo A; Cáceres, Abraham G; Sakurai, Tatsuya; Martini-Robles, Luiggi; Uezato, Hiroshi; Mimori, Tatsuyuki; Katakura, Ken; Hashiguchi, Yoshihisa; Kato, Hirotomo

2014-04-01

Entomological monitoring of Leishmania infection in leishmaniasis endemic areas offers epidemiologic advantages for predicting the risk and expansion of the disease, as well as evaluation of the effectiveness of control programs. In this study, we developed a highly sensitive loop-mediated isothermal amplification (LAMP) method for the mass screening of sand flies for Leishmania infection based on the 18S rRNA gene. The LAMP technique could detect 0.01 parasites, which was more sensitive than classical PCR. The method was robust and could amplify the target DNA within 1h from a crude sand fly template without DNA purification. Amplicon detection could be accomplished by the newly developed colorimetric malachite green (MG)--mediated naked eye visualization. Pre-addition of MG to the LAMP reaction solution did not inhibit amplification efficiency. The field applicability of the colorimetric MG-based LAMP assay was demonstrated with 397 field-caught samples from the endemic areas of Ecuador and eight positive sand flies were detected. The robustness, superior sensitivity, and ability to produce better visual discriminatory reaction products than existing LAMP fluorescence and turbidity assays indicated the field potential usefulness of this new method for surveillance and epidemiological studies of leishmaniasis in developing countries. Copyright © 2013 Elsevier B.V. All rights reserved.

Molecular Identification of Leishmania spp. in Sand Flies (Diptera: Psychodidae: Phlebotominae) in the Lençóis Maranhenses National Park, Brazil.

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Pereira-Filho, Adalberto Alves; Fonteles, Raquel Silva; Bandeira, Maria da Conceição Abreu; Moraes, Jorge Luiz Pinto; Rebêlo, José Manuel Macário; Melo, Maria Norma

2018-02-20

Sand flies are very common in the region of Lençóis Maranhenses National Park, an important tourist attraction in Brazil. However, the role of some species and their relative importance locally in Leishmania Ross 1903 transmission is unclear. The objective of this study was to identify Leishmania infection in phlebotomine sand flies collected around the Lençóis Maranhenses National Park, an important conservation area and popular international/national tourist destination with a high incidence of leishmaniasis. Sand flies were collected in peridomiciliary areas on the tourist route from September 2012 to August 2013. The captured females were subjected to molecular analyses for the detection of Leishmania DNA. Sand flies were infected with four Leishmania species: Leishmania (Viannia) braziliensis (Vianna, 1911) was found in Lutzomyia whitmani (Antunes and Coutinho, 1939) (2.1%) and Lutzomyia longipalpis (Lutz and Neiva, 1912) (1.7%); Leishmania (Leishmania) infantum (Nicole, 1908) infected Lutzomyia wellcomei (Fraiha, Shaw, and Lainson, 1971) (20%), Lutzomyia sordellii (Shannon and Del Ponte, 1927) (4.3%), Lu. longipalpis (3.7%), and Lu. whitmani (0.8%); Leishmania (Leishmania) amazonensis (Lainson & Shaw, 1972) was found in Lu. whitmani (0.58%), while Leishmania (Viannia) lainsoni infected Lutzomyia evandroi (Costa Lima and Antunes, 1936) (3.4%), Lu. longipalpis (1.06%), and Lu. whitmani (0.29%). The occurrence of these parasites requires control measures to reduce the incidence of cutaneous leishmaniasis and to contain a possible epidemic of visceral leishmaniasis, the most severe form of the disease.

The midgut transcriptome of Lutzomyia longipalpis: comparative analysis of cDNA libraries from sugar-fed, blood-fed, post-digested and Leishmania infantum chagasi-infected sand flies

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Elnaiem Dia-Eldin

2008-01-01

Full Text Available Abstract Background In the life cycle of Leishmania within the alimentary canal of sand flies the parasites have to survive the hostile environment of blood meal digestion, escape the blood bolus and attach to the midgut epithelium before differentiating into the infective metacyclic stages. The molecular interactions between the Leishmania parasites and the gut of the sand fly are poorly understood. In the present work we sequenced five cDNA libraries constructed from midgut tissue from the sand fly Lutzomyia longipalpis and analyzed the transcripts present following sugar feeding, blood feeding and after the blood meal has been processed and excreted, both in the presence and absence of Leishmania infantum chagasi. Results Comparative analysis of the transcripts from sugar-fed and blood-fed cDNA libraries resulted in the identification of transcripts differentially expressed during blood feeding. This included upregulated transcripts such as four distinct microvillar-like proteins (LuloMVP1, 2, 4 and 5, two peritrophin like proteins, a trypsin like protein (Lltryp1, two chymotrypsin like proteins (LuloChym1A and 2 and an unknown protein. Downregulated transcripts by blood feeding were a microvillar-like protein (LuloMVP3, a trypsin like protein (Lltryp2 and an astacin-like metalloprotease (LuloAstacin. Furthermore, a comparative analysis between blood-fed and Leishmania infected midgut cDNA libraries resulted in the identification of the transcripts that were differentially expressed due to the presence of Leishmania in the gut of the sand fly. This included down regulated transcripts such as four microvillar-like proteins (LuloMVP1,2, 4 and 5, a Chymotrypsin (LuloChym1A and a carboxypeptidase (LuloCpepA1, among others. Upregulated midgut transcripts in the presence of Leishmania were a peritrophin like protein (LuloPer1, a trypsin-like protein (Lltryp2 and an unknown protein. Conclusion This transcriptome analysis represents the largest set

Comparison of Bloodmeal Digestion and the Peritrophic Matrix in Four Sand Fly Species Differing in Susceptibility to Leishmania donovani.

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Pruzinova, Katerina; Sadlova, Jovana; Seblova, Veronika; Homola, Miroslav; Votypka, Jan; Volf, Petr

2015-01-01

The early stage of Leishmania development in sand flies is closely connected with bloodmeal digestion. Here we compared various parameters of bloodmeal digestion in sand flies that are either susceptible (Phlebotomus argentipes and P. orientalis) or refractory (P. papatasi and Sergentomyia schwetzi) to Leishmania donovani, to study the effects on vector competence. The volume of the bloodmeal ingested, time of defecation of bloodmeal remnants, timing of formation and degradation of the peritrophic matrix (PM) and dynamics of proteolytic activities were compared in four sand fly species. Both proven vectors of L. donovani showed lower trypsin activity and slower PM formation than refractory species. Interestingly, the two natural L. donovani vectors strikingly differed from each other in secretion of the PM and midgut proteases, with P. argentipes possessing fast bloodmeal digestion with a very high peak of chymotrypsin activity and rapid degradation of the PM. Experimental infections of P. argentipes did not reveal any differences in vector competence in comparison with previously studied P. orientalis; even the very low initial dose (2×103 promastigotes/ml) led to fully developed late-stage infections with colonization of the stomodeal valve in about 40% of females. We hypothesise that the period between the breakdown of the PM and defecation of the bloodmeal remnants, i.e. the time frame when Leishmania attach to the midgut in order to prevent defecation, could be one of crucial parameters responsible for the establishment of Leishmania in the sand fly midgut. In both natural L. donovani vectors this period was significantly longer than in S. schwetzi. Both vectors are equally susceptible to L. donovani; as average bloodmeal volumes taken by females of P. argentipes and P. orientalis were 0.63 μl and 0.59 μl, respectively, an infective dose corresponding to 1-2 parasites was enough to initiate mature infections.

Baseline susceptibility to pyrethroid and organophosphate insecticides in two old world sand fly species (diptera: psychodidae)

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A study was conducted with support from the Department of Defense’s Deployed Warfighter Protection (DWFP) Program to evaluate the susceptibility of two old world sand fly species, Phlebotomus papatasi and P. duboscqi, to a number of commonly used pyrethroid and organophosphate insecticides. A simpl...

Impact of phlebotomine sand flies on U.S. military operations at Tallil Air Base, Iraq: 4. Detection and identification of leishmania parasites in sand flies.

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Coleman, Russell E; Hochberg, Lisa P; Swanson, Katherine I; Lee, John S; McAvin, James C; Moulton, John K; Eddington, David O; Groebner, Jennifer L; O'Guinn, Monica L; Putnam, John L

2009-05-01

Sand flies collected between April 2003 and November 2004 at Tallil Air Base, Iraq, were evaluated for the presence of Leishmania parasites using a combination of a real-time Leishmania-generic polymerase chain reaction (PCR) assay and sequencing of a 360-bp fragment of the glucose-6-phosphate-isomerase (GPI) gene. A total of 2,505 pools containing 26,574 sand flies were tested using the real-time PCR assay. Leishmania DNA was initially detected in 536 pools; however, after extensive retesting with the real-time PCR assay, a total of 456 pools were considered positive and 80 were considered indeterminate. A total of 532 samples were evaluated for Leishmania GPI by sequencing, to include 439 PCR-positive samples, 80 PCR-indeterminate samples, and 13 PCR-negative samples. Leishmania GPI was detected in 284 samples that were sequenced, to include 281 (64%) of the PCR-positive samples and 3 (4%) of the PCR-indeterminate samples. Of the 284 sequences identified as Leishmania, 261 (91.9%) were L. tarentolae, 18 (6.3%) were L. donovani-complex parasites, 3 (1.1%) were L. tropica, and 2 were similar to both L. major and L. tropica. Minimum field infection rates were 0.09% for L. donovani-complex parasites, 0.02% for L. tropica, and 0.01% for the L. major/tropica-like parasite. Subsequent sequencing of a 600-bp region of the "Hyper" gene of 12 of the L. donovani-complex parasites showed that all 12 parasites were L. infantum. These data suggest that L. infantum was the primary leishmanial threat to U.S. military personnel deployed to Tallil Air Base. The implications of these findings are discussed.

Molecular Detection of Leishmania DNA in Wild-Caught Phlebotomine Sand Flies (Diptera: Psychodidae) From a Cave in the State of Minas Gerais, Brazil.

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Carvalho, G M L; Brazil, R P; Rêgo, F D; Ramos, M C N F; Zenóbio, A P L A; Andrade Filho, J D

2017-01-01

Leishmania spp. are distributed throughout the world, and different species are associated with varying degrees of disease severity. In Brazil, Leishmania transmission involves several species of phlebotomine sand flies that are closely associated with different parasites and reservoirs, and thereby giving rise to different transmission cycles. Infection occurs during the bloodmeals of sand flies obtained from a variety of wild and domestic animals, and sometimes from humans. The present study focused on detection of Leishmania DNA in phlebotomine sand flies from a cave in the state of Minas Gerais. Detection of Leishmania in female sand flies was performed with ITS1 PCR-RFLP (internal transcribed spacer 1) using HaeIII enzyme and genetic sequencing for SSUrRNA target. The survey of Leishmania DNA was carried out on 232 pools and the parasite DNA was detected in four: one pool of Lutzomyia cavernicola (Costa Lima, 1932), infected with Le. infantum (ITS1 PCR-RFLP), two pools of Evandromyia sallesi (Galvão & Coutinho, 1939), both infected with Leishmania braziliensis complex (SSUrRNA genetic sequencing analysis), and one pool of Sciopemyia sordellii (Shannon & Del Ponte, 1927), infected with subgenus Leishmania (SSUrRNA genetic sequencing analysis). The present study identified the species for Leishmania DNA detected in four pools of sand flies, all of which were captured inside the cave. These results represent the first molecular detection of Lu cavernicola with Le infantum DNA, Sc sordellii with subgenus Leishmania DNA, and Ev sallesi with Leishmania braziliensis complex DNA. The infection rate in females captured for this study was 0.17%. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Current and future niche of North and Central American sand flies (Diptera: psychodidae in climate change scenarios.

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David Moo-Llanes

Full Text Available Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector's ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i potential change in niche breadth, ii direction and magnitude of niche centroid shifts, iii shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3, for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%, while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys' ENM and human exposure to vectors of Leishmaniases.

Current and Future Niche of North and Central American Sand Flies (Diptera: Psychodidae) in Climate Change Scenarios

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Moo-Llanes, David; Ibarra-Cerdeña, Carlos N.; Rebollar-Téllez, Eduardo A.; Ibáñez-Bernal, Sergio; González, Camila; Ramsey, Janine M.

2013-01-01

Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector's ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i) potential change in niche breadth, ii) direction and magnitude of niche centroid shifts, iii) shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3), for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%), while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys' ENM and human exposure to vectors of Leishmaniases. PMID:24069478

Effect of class F fly ash on fine sand compaction through soil stabilization.

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Mahvash, Siavash; López-Querol, Susana; Bahadori-Jahromi, Ali

2017-03-01

This paper presents the results of an experimental investigation carried out to evaluate the effect of fly ash (FA) on fine sand compaction and its suitability as a material for embankments. The literature review demonstrates the lack of research on stabilization of sandy material using FA. The study is concerned with the role of FA content in stabilized soil physical characteristics. The main aim of this paper is to determine the optimum quantity of FA content for stabilization of this type of soil. This is achieved through particle size distribution and compaction (standard proctor) tests. The sand was stabilized with three proportions of FA (5%, 10% and 15%) and constant cement content of 3% was used as an activator. For better comparison, the sand was also stabilized by 3% cement only so that the effect of FA could be observed more clearly. The results were in line with the literature for other types of soil, i.e. as the % of FA increases, reduction in maximum dry density and higher optimum moisture content were observed.

Effect of class F fly ash on fine sand compaction through soil stabilization

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Siavash Mahvash

2017-03-01

Full Text Available This paper presents the results of an experimental investigation carried out to evaluate the effect of fly ash (FA on fine sand compaction and its suitability as a material for embankments. The literature review demonstrates the lack of research on stabilization of sandy material using FA. The study is concerned with the role of FA content in stabilized soil physical characteristics. The main aim of this paper is to determine the optimum quantity of FA content for stabilization of this type of soil. This is achieved through particle size distribution and compaction (standard proctor tests. The sand was stabilized with three proportions of FA (5%, 10% and 15% and constant cement content of 3% was used as an activator. For better comparison, the sand was also stabilized by 3% cement only so that the effect of FA could be observed more clearly. The results were in line with the literature for other types of soil, i.e. as the % of FA increases, reduction in maximum dry density and higher optimum moisture content were observed.

Natural Leishmania (Viannia) spp. infections in phlebotomine sand flies (Diptera: Psychodidae) from the Brazilian Amazon region reveal new putative transmission cycles of American cutaneous leishmaniasis

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de Souza, Adelson Alcimar Almeida; dos Santos, Thiago Vasconcelos; Jennings, Yara Lúcia Lins; Ishikawa, Edna Aoba Yassui; Barata, Iorlando da Rocha; Silva, Maria das Graças Soares; Lima, José Aprígio Nunes; Shaw, Jeffrey; Lainson, Ralph; Silveira, Fernando Tobias

2016-01-01

In Amazonian Brazil the etiological agents of American cutaneous leishmaniasis (ACL) belong to at least seven Leishmania species but little is known about the putative phlebotomine sand fly vectors in different biomes. In 2002–2003 a survey of the phlebotomine fauna was undertaken in the “Floresta Nacional do Tapajós”, Belterra municipality, in the lower Amazon region, western Pará State, Brazil, where we recently confirmed the presence of a putative hybrid parasite, L. (V.) guyanensis × L. (V.) shawi shawi. Sand flies were collected from Centers for Disease Control (CDC) light traps, Shannon traps and by aspiration on tree bases. Females were dissected and attempts to isolate any flagellate infections were made by inoculating homogenized midguts into Difco B45 medium. Isolates were characterized by monoclonal antibodies and isoenzyme electrophoresis. A total of 9,704 sand flies, belonging to 68 species or subspecies, were collected. Infections were found in the following sand flies: L. (V.) naiffi with Psychodopygus hirsutus hirsutus (1) and Ps. davisi (2); and L. (V.) shawi shawi with Nyssomyia whitmani (3) and Lutzomyia gomezi (1). These results provide strong evidence of new putative transmission cycles for L. (V.) naiffi and L. (V.) s. shawi. PMID:27235194

Species composition of sand flies and bionomics of Phlebotomus papatasi and P. sergenti (Diptera: Psychodidae) in cutaneous leishmaniasis endemic foci, Morocco.

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Boussaa, Samia; Kahime, Kholoud; Samy, Abdallah M; Salem, Abdelkrim Ben; Boumezzough, Ali

2016-02-02

Cutaneous Leishmaniasis (CL) is one of the most neglected tropical diseases in Morocco. Leishmania major and L. tropica are the main culprits identified in all endemic foci across the country. These two etiological agents are transmitted by Phlebotomus papatasi and P. sergenti, the two most prevalent sand fly species in Morocco. Previous studies reflected gaps of knowledge regarding the environmental fingerprints that affect the distribution of these two potential vectors across Morocco. The sand flies were collected from 48 districts across Morocco using sticky paper traps. Collected specimens were preserved in 70% ethanol for further processing and identification. Male and female densities were calculated in each site to examine their relations to the environmental conditions across these sites. The study used 19 environmental variables including precipitation, aridity, elevation, soil variables and a composite representing maximum, minimum and mean of day- and night-time Land Surface Temperature (LST), and Normalized Difference Vegetation Index (NDVI). A total of 11,717 specimens were collected during this entomological survey. These specimens represented 11 species of two genera; Phlebotomus and Sergentomyia. Correlations of the sand fly densities with the environmental variables were estimated to identify the variables which influence the distribution of the two potential vectors, Phlebotomus papatasi and P. sergenti, associated with all CL endemic foci across the country. The density of P. papatasi was most affected by temperature changes. The study showed a significant positive correlation between the densities of both sexes of P. papatasi and night-time temperatures. Both P. papatasi and P. sergenti showed a negative correlation with aridity, but, such correlation was only significant in case of P. papatasi. NDVI showed a positive correlation only with densities of P. sergenti, while, soil PH and soil water stress were negatively correlated with the

Properties of Fly Ash Blocks Made from Adobe Mould

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Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

2018-06-01

Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

Properties of Fly Ash Blocks Made from Adobe Mould

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Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

2018-02-01

Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

The Transcriptome of Leishmania major Developmental Stages in Their Natural Sand Fly Vector.

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Inbar, Ehud; Hughitt, V Keith; Dillon, Laura A L; Ghosh, Kashinath; El-Sayed, Najib M; Sacks, David L

2017-04-04

The life cycle of the Leishmania parasite in the sand fly vector involves differentiation into several distinctive forms, each thought to represent an adaptation to specific microenvironments in the midgut of the fly. Based on transcriptome sequencing (RNA-Seq) results, we describe the first high-resolution analysis of the transcriptome dynamics of four distinct stages of Leishmania major as they develop in a natural vector, Phlebotomus duboscqi The early transformation from tissue amastigotes to procyclic promastigotes in the blood-fed midgut was accompanied by the greatest number of differentially expressed genes, including the downregulation of amastins, and upregulation of multiple cell surface proteins, sugar and amino acid transporters, and genes related to glucose metabolism and cell cycle progression. The global changes accompanying post-blood meal differentiation of procyclic promastigotes to the nectomonad and metacyclic stages were less extensive, though each displayed a unique signature. The transcriptome of nectomonads, which has not been studied previously, revealed changes consistent with cell cycle arrest and the upregulation of genes associated with starvation and stress, including autophagic pathways of protein recycling. Maturation to the infective, metacyclic stage was accompanied by changes suggesting preadaptation to the intracellular environment of the mammalian host, demonstrated by the amastigote-like profiles of surface proteins and metabolism-related genes. Finally, a direct comparison between sand fly-derived and culture-derived metacyclics revealed a reassuring similarity between the two forms, with the in vivo forms distinguished mainly by a stronger upregulation of transcripts associated with nutrient stress. IMPORTANCE The life cycle of Leishmania parasites in the sand fly vector includes their growth and development as morphologically distinct forms of extracellular promastigotes found within the different microenvironments of the

Study of sand flies (Diptera: Psychodidae) in visceral and cutaneous leishmaniasis areas in the central-western state of Minas Gerais, Brazil.

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Nascimento, Bruno Warlley Leandro; Saraiva, Lara; Neto, Rafael Gonçalves Teixeira; Meira, Paula Cavalcante Lamy Serra e; Sanguinette, Cristiani de Castilho; Tonelli, Gabriel Barbosa; Botelho, Helbert Antônio; Belo, Vinícius Silva; Silva, Eduardo Sérgio da; Gontijo, Célia Maria Ferreira; Filho, José Dilermando Andrade

2013-03-01

The transmission of Leishmania involves several species of sand flies that are closely associated with various parasites and reservoirs, with differing transmission cycles in Brazil. A study on the phlebotomine species composition has been conducted in the municipality of Divinópolis, Minas Gerais, Brazil, an endemic area for cutaneous leishmaniasis (CL), which has intense occurrence of visceral leishmaniasis (VL) cases. In order to study the sand flies populations and their seasonality, CDC light traps (HP model) were distributed in 15 houses which presented at least one case of CL or VL and in five urban parks (green areas). Collections were carried out three nights monthly from September 2010 to August 2011. A total of 1064 phlebotomine specimens were collected belonging to two genera and seventeen species: Brumptomyia brumpti, Lutzomyia bacula, Lutzomyia cortelezzii, Lutzomyia lenti, Lutzomyia sallesi, Lutzomyia longipalpis, Lutzomyia migonei, Lutzomyia intermedia, Lutzomyia neivai, Lutzomyia whitmani, Lutzomyia christenseni, Lutzomyia monticola, Lutzomyia pessoai, Lutzomyia aragaoi, Lutzomyia brasiliensis, Lutzomyia lutziana, and Lutzomyia sordellii. L. longipalpis, the main vector of Leishmania infantum in Brazil, was the most frequent species, accounting for 76.9% of the total, followed by L. lenti with 8.3%, this species is not a proven vector. Green and urban areas had different sand flies species composition, whereas the high abundance of L. longipalpis in urban areas and the presence of various vector species in both green and urban areas were also observed. Our data point out to the requirement of control measures against phlebotomine sand flies in the municipality of Divinópolis and adoption of strategies aiming entomological surveillance. Copyright © 2012 Elsevier B.V. All rights reserved.

Species of sand flies (Diptera: Psychodidae) collected from natural reserves in the Pacific and Darien regions of Colombia.

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Vivero, Rafael J; Contreras, María Angélica; Suaza, Juan D; Vélez, Iván D; Porter, Charles; Uribe, Sandra

2017-03-29

The departments of Chocó and Antioquia in Colombia show climatic and vegetation conditions favoring the establishment of vector species of the genus Lutzomyia and the transmission of Leishmania spp. to human populations entering conserved forest environments. To report the species of Phlebotomine sandflies present in three natural reserves in the Darien and Pacific regions of Colombia. Sand flies were collected specifically in the natural reserves El Aguacate (Acandí, Chocó), Nabugá (Bahía Solano, Chocó) and Tulenapa (Carepa, Antioquia). Sand flies were collected with CDC light traps, active search in resting places and Shannon traps. The taxonomic determination of species was based on taxonomic keys. For some species of taxonomic interest, we evaluated the partial sequences of the 5' region of COI gene. A total of 611 adult sand flies were collected: 531 in Acandí, 45 in Carepa and 35 in Bahía Solano. Seventeen species of the genus Lutzomyia, three of the genus Brumptomyia and one of the genus Warileya were identified. The genetic distances (K2P) and grouping supported (>99%) in the neighbor joining dendrogram were consistent for most established molecular operational taxonomic units (MOTU) of the Aragaoi group and clearly confirmed the identity of Lu. coutinhoi. Species that have importance in the transmission of leishmaniasis in Acandí, Bahía Solano and Carepa were identified. The presence of Lu. coutinhoi was confirmed and consolidated in Colombia.

Lutzomyia sand flies (Diptera: Psychodidae) from middle and lower Putumayo Department, Colombia, with new records to the country.

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Barreto, M; Burbano, M E; Barreto, P

2000-01-01

A total of 4,840 phlebotomine sand flies from 54 localities in Putumayo department (=state), in the Colombian Amazon region, were collected in Shannon traps, CDC light traps, resting places and from human baits. At least 42 Lutzomyia species were registered for the first time to the department. Psychodopygus and Nyssomyia were the subgenera with the greatest number of taxa, the most common species being L. (N.) yuilli and L. (N.) pajoti. They were sympatric in a wide zone of Putumayo, indicating that they should be treated as full species (new status). Among the anthropophilic sand flies, L. gomezi and L. yuilli were found in intradomiciliar, peridomestic, urban or forest habitats. L. richardwardi, L. claustrei, L. nocticola and L. micropyga are reported for the first time in the Colombian Amazon basin. L. pajoti, L. sipani and L. yucumensis are new records for Colombia.

Recombinant Salivary Proteins of Phlebotomus orientalis are Suitable Antigens to Measure Exposure of Domestic Animals to Sand Fly Bites.

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Sima, Michal; Ferencova, Blanka; Warburg, Alon; Rohousova, Iva; Volf, Petr

2016-03-01

Certain salivary proteins of phlebotomine sand flies injected into the host skin during blood-feeding are highly antigenic and elicit strong antibody-mediated immune responses in repeatedly-exposed hosts. These antibodies can be measured by enzyme-linked immuno sorbent assays (ELISAs) using salivary gland homogenates (SGHs) as the source of antigens and serve as a markers for exposure to biting sand flies. Large-scale screening for anti-sand fly saliva antibodies requires replacement of SGH with recombinant salivary proteins. In East Africa, Phlebotomus orientalis is the main vector of Leishmania donovani, a trypanosomatid parasite causing visceral leishmaniasis. We tested recombinant salivary proteins derived from Ph. orientalis saliva to study exposure of domestic animals to this sand fly species. Antigenic salivary proteins from Ph. orientalis were identified by immunoblot and mass spectrometry. Recombinant apyrase rPorSP15, yellow-related protein rPorSP24, ParSP25-like protein rPorSP65, D7-related protein rPorSP67, and antigen 5-related protein rPorSP76 were tested using ELISA with sera of domestic animals from L. donovani foci in Ethiopia where Ph. orientalis is present. Our results highlighted recombinant yellow-related protein rPorSP24 as the most promising antigen, displaying a high positive correlation coefficient as well as good sensitivity and specificity when compared to SGH. This recombinant protein was the most suitable one for testing sera of dogs, sheep, and goats. In addition, a different antigen, rPorSP65 was found efficacious for testing canine sera. Recombinant salivary proteins of Ph. orientalis, specifically rPorSP24, were shown to successfully substitute SGH in serological experiments to measure exposure of domestic animals to Ph. orientalis, the vector of L. donovani. The results suggest that rPorSP24 might be a suitable antigen for detecting anti-Ph. orientalis antibody-mediated reactions also in other host species.

Bloodmeal Identification in Field-Collected Sand Flies From Casa Branca, Brazil, Using the Cytochrome b PCR Method.

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Carvalho, G M L; Rêgo, F D; Tanure, A; Silva, A C P; Dias, T A; Paz, G F; Andrade Filho, J D

2017-07-01

PCR-based identification of vertebrate host bloodmeals has been performed on several vectors species with success. In the present study, we used a previously published PCR protocol followed by DNA sequencing based on primers designed from multiple alignments of the mitochondrial cytochrome b gene used to identify avian and mammalian hosts of various hematophagous vectors. The amplification of a fragment encoding a 359 bp sequence of the Cyt b gene yielded recognized amplification products in 192 female sand flies (53%), from a total of 362 females analyzed. In the study area of Casa Branca, Brazil, blood-engorged female sand flies such as Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1924), and Nyssomyia whitmani (Antunes & Coutinho, 1939) were analyzed for bloodmeal sources. The PCR-based method identified human, dog, chicken, and domestic rat blood sources. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Systematic relationships among Lutzomyia sand flies (Diptera: Psychodidae) of Peru and Colombia based on the analysis of 12S and 28S ribosomal DNA sequences.

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Beati, Lorenza; Cáceres, Abraham G; Lee, Jamie A; Munstermann, Leonard E

2004-02-01

Lutzomyia spp. are New World phlebotomine sand flies, many of which are involved in the transmission of human diseases, such as leishmaniases and bartonellosis. The systematic classification of the approximately 400 species in the genus has been based on morphological characters, but the relationships within the genus are still very much in question. We have inferred phylogenies of 32 species of phlebotomine sand flies belonging to seven sub-genera and two species groups, by using fragments of the mitochondrial small subunit (12SrRNA) and of the nuclear large subunit (28SrRNA) ribosomal gene sequences. The subgenus Helcocyrtomyia and the Verrucarum species group, prominent representatives of the Peruvian sand fly fauna, were represented by 11 and 7 species, respectively. Although based on a limited number of taxa, the resulting phylogenies, based on 837 characters, provide an initial phylogenetic backbone for the progressive reconstruction of infrageneric relationships within Lutzomyia.

Dispersal of phlebotomine sand flies (Diptera: Psychodidae in a colombian focus of leishmania (Viannia brasiliensis

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Bruce Alexander

1992-09-01

Full Text Available Dispersal of five species of phlebotomine sand flies was studied in a coffee plantation near Arboledas, Colombia by mark-release-recapture studies using fluorescent powders. The estimated recapture rate for males of Lutzomyia shannoni marked and released during the day was 28.1% significantly higher than that for all other species (p < 0.05. Recapture rate of female Lu. shannoni was 9.5% and no females of the other four species were recovered. This suggests either that Lu. shannoni is a more sedentary species than the others, or that the large trees on wich these insects were captured and recaptured function as foci of lekking behaviour in males. The high recapture rates of females of this species may indicate that oviposition occurs in close proximity to the bases of these trees. Although most marked sand flies were recaptured within 200 m of their release point, a single female Lu. gomezi was recovered 960 m away 36 h after release. This suggests that the dispersal capacity of Lutzomyia species may be greater than has been though, an important consideration in future control programs directed against these insects in Leishmania-endemic areas.

Application of Flumethrin Pour-On on Reservoir Dogs and Its Efficacy against Sand Flies in Endemic Focus of Visceral Leishmaniasis, Meshkinshahr, Iran

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MohammadReza Jalilnavaz

2015-10-01

Full Text Available Background: Visceral leishmaniasis (VL is one of the most important parasitic zoonotic diseases in the world. Do­mestic dogs are the main domestic reservoirs of VL in endemic foci of Iran. Various methods, including vaccination, treatment of dogs, detection and removal of infected dogs have different results around the world. General policy on control of canine visceral leishmaniasis is protection of them from sand fly bites. The aim of this study was evalua­tion of pour-on application of flumethrin on dogs against blood-feeding and mortality of field-caught sand flies.Methods: Once every 20 days from May untill September 2013, the treated and control dogs were exposed with field caught sandflies for 2 hours under bed net traps. After the exposure time, both alive and dead sand flies were trans­ferred in netted cups to the laboratory. The mortality rate of them was assessed after 24 hours. The blood-fed or un­fed conditions were determined 2 hours after exposure to the dogs under stereomicroscope.Results: The blood feeding index was varied from 12.0 to 25.0 % and 53.0 to 58.0 % for treated and control dogs respectively (P< 0.0001. The blood feeding inhibition was 75.0–87.0 % and 41.0–46.0 % for the control and treated dogs (P< 0.0001, respectively.The total mortality rate was 94.0–100 % and 19.0–58.0 % respectively for the treated and control groups (P< 0.001.Conclustion: Application of pour-on flumethrin on dogs caused 90–100 % mortality until 2.5 month and inhibited the blood-feeding of sand flies. 

Species Composition of Sand Flies (Diptera: Psychodidae) and Modeling the Spatial Distribution of Main Vectors of Cutaneous Leishmaniasis in Hormozgan Province, Southern Iran.

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Hanafi-Bojd, Ahmad Ali; Khoobdel, Mehdi; Soleimani-Ahmadi, Moussa; Azizi, Kourosh; Aghaei Afshar, Abbas; Jaberhashemi, Seyed Aghil; Fekri, Sajjad; Safari, Reza

2018-02-28

Cutaneous Leishmaniasis (CL) is one of the main neglected vector-borne diseases in the Middle East, including Iran. This study aimed to map the spatial distribution and species composition of sand flies in Hormozgan Province and to predict the best ecological niches for main CL vectors in this area. A database that included all earlier studies on sand flies in Hormozgan Province was established. Sand flies were also collected from some localities across the province. Prediction maps for main vectors were developed using MaxEnt model. A total of 27 sand fly species were reported from the study area. Phlebotomus papatasi Scopoli, Phlebotomus sergenti s.l. Parrot, Phlebotomus alexandri Sinton, Sergentomyia sintoni Pringle, Sergentomyia clydei Sinton, Sergentomyia tiberiadis Adler, and Sergentomyia baghdadis Adler (Diptera: Psychodidae) had the widest distribution range. The probability of their presence as the main vectors of CL was calculated to be 0.0003-0.9410 and 0.0031-0.8880 for P. papatasi and P. sergenti s.l., respectively. The best ecological niches for P. papatasi were found in the central south, southeast, and a narrow area in southwest, whereas central south to northern area had better niches for P. sergenti s.l. The endemic areas are in Bandar-e Jask, where transmission occurs, whereas in Bastak, the cases were imported from endemic foci of Fars province. In conclusion, proven and suspected vectors of CL and VL were recorded in this study. Due to the existence of endemic foci of CL, and favorite ecological niches for its vectors, there is potential risk of emerging CL in new areas.

The Study of Sand Fly Fauna in an Endemic Focus for Cutaneous Leishmaniasis in Fasa from April to October in the year 2013

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Mehdi Sharafi

2015-02-01

Full Text Available Background & Objectives: Leishmaniasis as a zoonosis disease seen in three forms including Cutaneous, mucocutaneous, and visceral (kala- azar. The Leishmania transferred by sand flies is the causative agent of this disease. Considering that leishmaniasis is an endemic disease in Fasa, this study was performed to determine the sand fly species of Fasa, Materials & Methods: In this cross- sectional study from April to September 2014, the fauna of sand flies was investigated. Sampling was done in villages with above, medium, and low incidence by using sticky traps every 15 days. Then, captured specimens were mounted and identified by specific key. Results: 3842 sand flies were captured for ecological studies. 2305 of them (60% were males and the rest of them were females. 1152 specimens (30% of them were from indoors and the rest were from outdoors. Totally, 10 species were identified including Phlebotomus. Papatasi, Ph. Alexandri, Ph. Sergenti, Ph. Mongolensis, Ph. Bergeroti, Ph. Caucasicus, Sergentomyia theodori, S. Baghdadis, S. sintuni, and S. antennata. Among captured specimens Phlebotomus Papatasi, Ph. Sergenti had the first and the second places, respectively. Conclusion: Sandflies in Fasa are very active with high prevalence and species diversity. Phlebotomus Papatasi as the predominant species transfers Leishmania from rodents to humans. This subject is related to the prevalence of rural leishmaniasis in this area. According to the semi-domestic vector, spraying is not helpful in a rural foci of cutaneous leishmaniasis. But the control of reservoir and educating the residents about prevention ways of bite are effective in disease control and prevention.

The current status of phlebotomine sand flies in Albania and incrimination of Phlebotomus neglectus (Diptera, Psychodidae) as the main vector of Leishmania infantum.

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Velo, Enkelejda; Bongiorno, Gioia; Kadriaj, Perparim; Myrseli, Teita; Crilly, James; Lika, Aldin; Mersini, Kujtim; Di Muccio, Trentina; Bino, Silvia; Gramiccia, Marina; Gradoni, Luigi; Maroli, Michele

2017-01-01

The incidence of visceral leishmaniasis (VL) in Albania is higher than in other countries of southern Europe, however the role of local sand fly species in the transmission of Leishmania infantum was not addressed conclusively. In 2006, a country-wide collection of sand flies performed in 14 sites selected based on recent occurrence of VL cases showed that Phlebotomus neglectus was by far the most prevalent species (95.6%). Furthermore, 15% of pools made from 422 P. neglectus females tested positive for Leishmania sp. genomic DNA. In the same year, Culicoides trapping was performed for bluetongue disease surveillance in 91 sites of southern Albania, targeting livestock farms regardless recent occurrence of VL in the surveyed areas. In 35 sites where sand flies were collected along with midges, Phlebotomus perfiliewi was the most prevalent among the Phlebotomus species identified, however search for leishmanial DNA in females of this species was unsuccessful. In 2011, sand flies were trapped in 4 sites of north Albania characterized by high VL incidence, and females were dissected to search for Leishmania infections. Both P. neglectus and P. tobbi were collected at high densities. Two positive specimens were detected from a sample of 64 P. neglectus trapped in one site (3.1%). Parasites were successfully cultured from one specimen and characterized as belonging to Leishmania infantum zymodeme MON-1, the only zymodeme so far identified as the agent of human and canine leishmaniasis in the country. Altogether our studies indicate that P. neglectus is the main leishmaniasis vector in Albania.

Andean cutaneous leishmaniasis (Andean-CL, uta) in Peru and Ecuador: the vector Lutzomyia sand flies and reservoir mammals.

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Hashiguchi, Yoshihisa; Gomez L, Eduardo A; Cáceres, Abraham G; Velez, Lenin N; Villegas, Nancy V; Hashiguchi, Kazue; Mimori, Tatsuyuki; Uezato, Hiroshi; Kato, Hirotomo

2018-02-01

The vector Lutzomyia sand flies and reservoir host mammals of the Leishmania parasites, causing the Andean cutaneous leishmaniasis (Andean-CL, uta) in Peru and Ecuador were thoroughly reviewed, performing a survey of literatures including our unpublished data. The Peruvian L. (V.) peruviana, a principal Leishmania species causing Andean-CL in Peru, possessed three Lutzomyia species, Lu. peruensis, Lu. verrucarum and Lu. ayacuchensis as vectors, while the Ecuadorian L. (L.) mexicana parasite possessed only one species Lu. ayacuchensis as the vector. Among these, the Ecuadorian showed a markedly higher rate of natural Leishmania infections. However, the monthly and diurnal biting activities were mostly similar among these vector species was in both countries, and the higher rates of infection (transmission) reported, corresponded to sand fly's higher monthly-activity season (rainy season). The Lu. tejadai sand fly participated as a vector of a hybrid parasite of L. (V.) braziliensis/L. (V.) peruviana in the Peruvian Andes. Dogs were considered to be principal reservoir hosts of the L. (V.) peruviana and L. (L.) mexicana parasites in both countries, followed by other sylvatic mammals such as Phyllotis andium, Didelphis albiventris and Akodon sp. in Peru, and Rattus rattus in Ecuador, but information on the reservoir hosts/mammals was extremely poor in both countries. Thus, the Peruvian disease form demonstrated more complicated transmission dynamics than the Ecuadorian. A brief review was also given to the control of vector and reservoirs in the Andes areas. Such information is crucial for future development of the control strategies of the disease. Copyright © 2017 Elsevier B.V. All rights reserved.

Molecular characterization of leishmania infection from naturally infected sand flies caught in a focus of cutaneous leishmaniasis (eastern iran.

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Mohammad Akhoundi

2013-12-01

Full Text Available Cutaneous leishmaniasis due to Leishmania major is a serious and increasing problem affecting many rural areas of 17 out of 31 provinces in Iran. Little is known about sand fly fauna and leishmaniases in Eastern Iran and no study has been carried out in Sarbisheh County. The aim of this study was to determine sand flies composition and probable Leishmania infection to find the probable vectors of leishmaniasis in Sarbisheh district.Sand flies were caught using both sticky papers and CDC light traps in August 2010. They were identified morphologically and analyzed for Leishmania infection by amplification of ITS-rDNA.Totally, 842 specimens were caught and 8 species recorded. They belonged to the genera Phlebotomus and Sergentomyia: P. (Phlebotomus papatasi, P. (Paraphlebotomus sergenti, P. (Pa. caucasicus, P. (Pa. mongolensis, P. (Pa. jacusieli, S. (Sergentomyia dentata, S. (Se. sintoni and S. (Sintonius clydei. All collected females were processed for Leishmania DNA detection by PCR amplifying of Internal Transcribed Spacer1 (partial sequence, 5.8S (complete sequence and ITS2 (partial sequence fragments. Thirteen females were positive for Leishmania DNA. The sequencing of the 430 bp amplicons indicated that 9 P. papatasi and 3 females belonging to the Caucasicus group carried L. major DNA whereas one P. sergenti carried L. tropica DNA.Phlebotomus papatasi and P. sergenti are, like in several places, the probable vectors of cutaneous leishmaniases in this emerging or unknown focus of cutaneous leishmaniases.

Colonization of Lutzomyia verrucarum and Lutzomyia longipalpis Sand Flies (Diptera: Psychodidae) by Bartonella bacilliformis, the Etiologic Agent of Carrión's Disease.

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Battisti, James M; Lawyer, Phillip G; Minnick, Michael F

2015-01-01

Bartonella bacilliformis is a pathogenic bacterium transmitted to humans presumably by bites of phlebotomine sand flies, infection with which results in a bi-phasic syndrome termed Carrión's disease. After constructing a low-passage GFP-labeled strain of B. bacilliformis, we artificially infected Lutzomyia verrucarum and L. longipalpis populations, and subsequently monitored colonization of sand flies by fluorescence microscopy. Initially, colonization of the two fly species was indistinguishable, with bacteria exhibiting a high degree of motility, yet still confined to the abdominal midgut. After 48 h, B. bacilliformis transitioned from bacillus-shape to a non-motile, small coccoid form and appeared to be digested along with the blood meal in both fly species. Differences in colonization patterns became evident at 72 h when B. bacilliformis was observed at relatively high density outside the peritrophic membrane in the lumen of the midgut in L. verrucarum, but colonization of L. longipalpis was limited to the blood meal within the intra-peritrophic space of the abdominal midgut, and the majority of bacteria were digested along with the blood meal by day 7. The viability of B. bacilliformis in L. longipalpis was assessed by artificially infecting, homogenizing, and plating for determination of colony-forming units in individual flies over a 13-d time course. Bacteria remained viable at relatively high density for approximately seven days, suggesting that L. longipalpis could potentially serve as a vector. The capacity of L. longipalpis to transmit viable B. bacilliformis from infected to uninfected meals was analyzed via interrupted feeds. No viable bacteria were retrieved from uninfected blood meals in these experiments. This study provides significant information toward understanding colonization of sand flies by B. bacilliformis and also demonstrates the utility of L. longipalpis as a user-friendly, live-vector model system for studying this severely neglected

Parasite load in the blood and skin of dogs naturally infected by Leishmania infantum is correlated with their capacity to infect sand fly vectors.

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Borja, Lairton Souza; Sousa, Orlando Marcos Farias de; Solcà, Manuela da Silva; Bastos, Leila Andrade; Bordoni, Marcelo; Magalhães, Jairo Torres; Larangeira, Daniela Farias; Barrouin-Melo, Stella Maria; Fraga, Deborah Bittencourt Mothé; Veras, Patrícia Sampaio Tavares

2016-10-15

The sand fly Lutzomyia longipalpis is primarily responsible for the transmission of visceral leishmaniasis (VL) in the New World, and dogs are considered to be the main urban reservoir of this disease. In order to improve the efficacy of control measures, it is essential to assess the transmission capacity of Leishmania infantum to the sand fly vector by naturally infected dogs. The present study investigated the existence of correlations between canine clinical presentation and the intensity of parasite load in the blood, skin and spleen of naturally infected dogs. In addition, we also attempted to establish correlations between the intensity of parasite load in canine tissue and the parasite load detected in sandflies five days after feeding on naturally infected dogs. A total of 23 dogs were examined and classified according to clinical manifestation of canine VL. Blood samples, splenic aspirate and skin biopsies were collected and parasite DNA was quantified by qPCR. Canine capacity to infect Lu. longipalpis with parasites was evaluated by xenodiagnosis and parasite loads were measured five days after feeding. No significant differences were observed with respect to canine clinical manifestation and the parasite loads detected in the blood, skin and spleen samples obtained from naturally infected dogs. Regardless of clinical canine visceral leishmaniasis (CVL) presentation and the degree of parasite burden, almost half of the dogs successfully infected sandflies with parasites, albeit to a low number of sandflies with correspondingly low parasite loads. Parasite loads in both canine blood and skin were shown to be positively correlated with the canine infectiousness to the sand fly vector, and positive correlations were also observed with respect to these tissues and the sand fly infection rate, as well as the parasite load detected in sandflies following xenodiagnosis. In conclusion, this indicates that parasite loads in both blood and skin can function as

Ecology, feeding and natural infection by Leishmania spp. of phlebotomine sand flies in an area of high incidence of American tegumentary leishmaniasis in the municipality of Rio Branco, Acre, Brazil.

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de Ávila, Márcia Moreira; Brilhante, Andreia Fernandes; de Souza, Cristian Ferreira; Bevilacqua, Paula Dias; Galati, Eunice Aparecida Bianchi; Brazil, Reginaldo Peçanha

2018-01-26

Phlebotomine sand flies (Diptera: Psychodidae) are insects of medical importance due to their involvement in the zoonotic transmission of Leishmania spp. to vertebrates. The aim of this work was to study the ecology of the sand fly fauna of two types of environments, a rural environment (the Transacreana Road) and an urban park (Horto Florestal Park), both located in the municipality of Rio Branco in the state of Acre, Brazil. Additionally, this study intended to investigate Leishmania infection and blood meal sources of these sand flies using molecular techniques. The sand fly fauna was studied in different environments (i.e. forest and peridomestic environments in a rural area, and an urban forest) using Shannon traps and HP light traps to collect sand fly specimens over 13 consecutive months (December 2014 to January 2016). For investigating natural infection by Leishmania and the source of sand fly blood meals, DNA samples were extracted from female sand flies and subjected to polymerase chain reaction targeting ITS1 and cytb genes. DNA sequencing was subsequently used to identify species of Leishmania and the source of blood meals. A total of 2515 individual sand flies of 43 species were collected and identified, Trichophoromyia auraensis (839; 33.35%), Trichophoromyia spp. (537; 21.35%) and Evandromyia saulensis (187; 7.43%) were more abundant in the rural area (S = 41 species) than in the urban forest. No significant differences were found in species richness between forest and peridomestic environments in the rural area (H = 0.04; P > 0.05), but a larger number of species was found in the forest. Leishmania DNA was sequenced in 13 samples, confirming the presence of L. (V.) braziliensis in Th. auraensis (n = 1), Ev. saulensis (n = 2), Ev. walkeri (n = 1), Ps. llanosmartinsi (n = 1), Pi. nevesi (n = 2), Ps. davisi (n = 1), Ps. ayrozai (n = 1), Pa. aragaoi (n = 1), Ny. antunesi (n = 1) and Ev. infraspinosa (n�

Flying insects and Campylobacter

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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...

Fauna of phlebotomine sand flies (Diptera, Psychodidae in areas with endemic American cutaneous leishmaniasis in the State of Mato Grosso do Sul, Brazil

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Paulo Silva de Almeida

2013-03-01

Full Text Available Fauna of phlebotomine sand flies (Diptera, Psychodidae in areas with endemic American cutaneous leishmaniasis in the State of Mato Grosso do Sul, Brazil. The aim of this study was to investigate the ecological aspects of the main vectors of American cutaneous leishmaniasis (ACL in four monitoring stations situated in the municipalities of Naviraí, Nova Andradina, Novo Horizonte do Sul and Rio Verde de Mato Grosso. For each monitoring station, the captures of sand flies were undertaken each month from July 2008 to June 2010 using CDC and Shannon traps. The CDC traps were installed simultaneously for three consecutive nights in three collection sites: intradomicile, peridomicile and edge of the forest. A Shannon trap was installed from dusk to 10 pm, inside the forest, one night per month. A total of 7,651 sand flies belonging to nine genera and twenty-nine species were captured. Nyssomyia neivai (52.95%, Psathyromyia hermanlenti (10.91%, Psathyromyia runoides (9.16%, Nyssomyia whitmani (7.95%, Psathyromyia aragaoi (4. 89%, Nyssomyia antunesi (3.14% and Evandromyia bourrouli (2.20% were the most frequent species. Approximately 65% of the sand flies were collected in the forest environment. The municipalities presented significantly different indexes of species diversity. Naviraí presented the lowest species diversity index, however, it showed the highest abundance. Novo Horizonte do Sul had the highest species diversity index, but the lowest abundance (< 5%. It is noteworthy the occurrence of vector species of Leishmania in the areas studied, especially in Naviraí, where Ny. neivai presented high frequencies which may explain the increased number of ACL cases in this municipality.

SALO, a novel classical pathway complement inhibitor from saliva of the sand fly Lutzomyia longipalpis.

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Ferreira, Viviana P; Fazito Vale, Vladimir; Pangburn, Michael K; Abdeladhim, Maha; Mendes-Sousa, Antonio Ferreira; Coutinho-Abreu, Iliano V; Rasouli, Manoochehr; Brandt, Elizabeth A; Meneses, Claudio; Lima, Kolyvan Ferreira; Nascimento Araújo, Ricardo; Pereira, Marcos Horácio; Kotsyfakis, Michalis; Oliveira, Fabiano; Kamhawi, Shaden; Ribeiro, Jose M C; Gontijo, Nelder F; Collin, Nicolas; Valenzuela, Jesus G

2016-01-13

Blood-feeding insects inject potent salivary components including complement inhibitors into their host's skin to acquire a blood meal. Sand fly saliva was shown to inhibit the classical pathway of complement; however, the molecular identity of the inhibitor remains unknown. Here, we identified SALO as the classical pathway complement inhibitor. SALO, an 11 kDa protein, has no homology to proteins of any other organism apart from New World sand flies. rSALO anti-complement activity has the same chromatographic properties as the Lu. longipalpis salivary gland homogenate (SGH)counterparts and anti-rSALO antibodies blocked the classical pathway complement activity of rSALO and SGH. Both rSALO and SGH inhibited C4b deposition and cleavage of C4. rSALO, however, did not inhibit the protease activity of C1s nor the enzymatic activity of factor Xa, uPA, thrombin, kallikrein, trypsin and plasmin. Importantly, rSALO did not inhibit the alternative or the lectin pathway of complement. In conclusion our data shows that SALO is a specific classical pathway complement inhibitor present in the saliva of Lu. longipalpis. Importantly, due to its small size and specificity, SALO may offer a therapeutic alternative for complement classical pathway-mediated pathogenic effects in human diseases.

Polymerase chain reaction-based assay for the detection and identification of sand fly gregarines in Lutzomyia longipalpis, a vector of visceral leishmaniasis.

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Caligiuri, Lorena G; Acardi, Soraya A; Santini, María Soledad; Salomón, Oscar D; McCarthy, Christina B

2014-06-01

Gregarines that parasitise phlebotomine sand flies belong to the genus Psychodiella and, even though they are highly host-specific, only five species have been described to date. Their most outstanding features include the unique localisation of the oocysts in the accessory glands of the female host, which ensures contamination of the egg surface during oviposition, and the fact that they naturally parasitise the vectors of Leishmania, causal agent of leishmaniasis. The type species, Ps. chagasi, was first described in Lutzomyia longipalpis, vector of visceral leishmaniasis (VL), from Brazil. We recently reported Ps. chagasi sequences in Lu. longipalpis from Posadas (Misiones, Argentina), an endemic VL location where this gregarine had not been previously recorded. In order to analyse the incidence of Ps. chagasi infections in Lu. longipalpis from this location, the aim of this study was to develop a diagnostic assay for sand fly gregarine parasites in Lu. longipalpis. For this, we designed primers using the Ps. chagasi sequences we previously identified and performed an in vitro validation by PCR amplification of the original sand fly samples. Their specificity and sensitivity as diagnostic primers were subsequently confirmed by PCR reactions using total DNA extracted from naturally infected Lu. longipalpis from the same location (Posadas, Argentina). © 2014 The Society for Vector Ecology.

Colonization of Lutzomyia verrucarum and Lutzomyia longipalpis Sand Flies (Diptera: Psychodidae) by Bartonella bacilliformis, the Etiologic Agent of Carrión’s Disease

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Battisti, James M.; Lawyer, Phillip G.; Minnick, Michael F.

2015-01-01

Bartonella bacilliformis is a pathogenic bacterium transmitted to humans presumably by bites of phlebotomine sand flies, infection with which results in a bi-phasic syndrome termed Carrión’s disease. After constructing a low-passage GFP-labeled strain of B. bacilliformis, we artificially infected Lutzomyia verrucarum and L. longipalpis populations, and subsequently monitored colonization of sand flies by fluorescence microscopy. Initially, colonization of the two fly species was indistinguishable, with bacteria exhibiting a high degree of motility, yet still confined to the abdominal midgut. After 48h, B. bacilliformis transitioned from bacillus-shape to a non-motile, small coccoid form and appeared to be digested along with the blood meal in both fly species. Differences in colonization patterns became evident at 72h when B. bacilliformis was observed at relatively high density outside the peritrophic membrane in the lumen of the midgut in L. verrucarum, but colonization of L. longipalpis was limited to the blood meal within the intra-peritrophic space of the abdominal midgut, and the majority of bacteria were digested along with the blood meal by day 7. The viability of B. bacilliformis in L. longipalpis was assessed by artificially infecting, homogenizing, and plating for determination of colony-forming units in individual flies over a 13-d time course. Bacteria remained viable at relatively high density for approximately seven days, suggesting that L. longipalpis could potentially serve as a vector. The capacity of L. longipalpis to transmit viable B. bacilliformis from infected to uninfected meals was analyzed via interrupted feeds. No viable bacteria were retrieved from uninfected blood meals in these experiments. This study provides significant information toward understanding colonization of sand flies by B. bacilliformis and also demonstrates the utility of L. longipalpis as a user-friendly, live-vector model system for studying this severely neglected

Are light traps baited with kairomones effective in the capture of Lutzomyia longipalpis and Lutzomyia intermedia? An evaluation of synthetic human odor as an attractant for phlebotomine sand flies (Diptera: Psychodidae: Phlebotominae).

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Andrade, Andrey J; Andrade, Mateus R; Dias, Edelberto S; Pinto, Mara C; Eiras, Alvaro E

2008-06-01

Phlebotomine sand flies are often captured with human bait and/or light traps, either with or without an animal bait. More recently, synthetic attractants have been used as bait in traps to improve the capture of phlebotomine sand flies as well as other insects of medical and veterinary importance. The aim of the present study was to evaluate the effects of the kairomone 1-octen-3-ol (octenol) and the synthetic human odor BG-Mesh Lure (BGML--lactic acid, caproic acid and ammonia) baited in modified CDC light traps on the capture of phlebotomine sand flies. The experiments followed the 5x5 Latin square design. Among the species caught, Lutzomyia intermedia apparently presented a dose-dependent response to octenol. The response obtained with the BGML, alone or in combination with octenol (5 mg/h), indicated some degree of attractiveness of these baits to different phlebotomine sand fly species. Octenol seems to be more attractive to L. intermedia than to Lutzomyia longipalpis, while the BGML presented a higher success in capturing L. longipalpis. When the components of the BGML were used separately, there was no increase in catching the female of L. intermedia. Apparently, there was no synergistic effect between the octenol and the BGML. In conclusion, the octenol and the BGML were demonstrated to be possible baits to attract some phlebotomine sand fly species.

Structural characterization of acetylcholinesterase 1 from the sand fly Lutzomyia longipalpis (Diptera: Psychodidae).

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Coutinho-Abreu, I V; Balbino, V Q; Valenzuela, J G; Sonoda, I V; Ramalho-Ortigão, J M

2007-07-01

Acetylcholinesterase (AChE) plays a key role in cholinergic impulse transmission, and it is the target enzyme for organophosphorus and carbamate insecticides. Two genes, AceI and AceII, have been characterized from different insect species, and point mutations in either gene can lead to significant resistance to these classes of insecticides. In this report, we describe the partial characterization of the AceI gene from Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae), and we show that the possibility exists for the development of a resistant phenotype to organophosphates and carbamates in sand flies. Our results point to the presence of a single AceI gene in L. longipalpis (LlAce1) and that AChE activity is inhibited by organophosphorus at a concentration of 5 x 10(-5) M. Regarding insecticide resistance, analysis of the truncated LlAce1 cDNA suggests that a single missense mutation leading to a glycine-to-serine substitution at amino acid position 119 (G119S) may arise in L. longipalpis, similar to what has been detected in Anopheles gambiae s.s. Another missense mutation involved in resistant phenotypes, F331W, detected in Culex tritaeniorhynchus Giles, is less likely to occur in L. longipalpis, because it faces codon constraint in this sand fly species. Comparison of the three-dimensional structures of the deduced amino acid sequence of the truncated LLAChE1 with that of An. gambiae and Cx. tritaeniorhynchus also suggests that similar structural modifications due to the missense amino acid changes in the active site gorge are detected in all three insects.

Nocturnal activity patterns of Lutzomyia longipalpis (Diptera: Psychodidae) at an endemic focus of visceral leishmaniasis in Colombia.

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Morrison, A C; Ferro, C; Pardo, R; Torres, M; Wilson, M L; Tesh, R B

1995-09-01

Nocturnal activity of the sand fly Lutzomyia longipalpis (Lutz & Neiva) was studied from August 1991 to July 1992 in a small rural community in Colombia where American visceral leishmaniasis is endemic. During 2 or 3 nights each month, sand flies were collected with hand-held aspirators each hour between 1730 and 0630 hours, from a pigpen and a cattle corral located 30 m apart. Host-seeking activity of L. longipalpis adults was characterized by 2 general patterns: (1) adult sand fly activity increased shortly after sunset and continued until just after sunrise, and (2) peak sand fly activity was greatest early in the evening (1830-2330 hours) and then declined steadily toward morning. Female L. longipalpis activity generally increased after 2030 hours, whereas that of males remained constant or declined as the evening progressed. There were seasonal differences in sand fly abundance between the 2 sites: peak abundance in the cattle corral occurred during hot, dry periods, whereas maximum abundance in the pigpen occurred when relative humidity was higher. Influence of relative humidity on activity varied with season. Sand fly activity tended to decrease at temperatures below 24 degrees C and increase in the presence of moonlight.

Lutzomyia sand fly diversity and rates of infection by Wolbachia and an exotic Leishmania species on Barro Colorado Island, Panama.

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Jorge Azpurua

2010-03-01

Full Text Available Sand flies (Diptera, Psychodidae, Phlebotominae in the genus Lutzomyia are the predominant vectors of the protozoan disease leishmaniasis in the New World. Within the watershed of the Panama Canal, the cutaneous form of leishmaniasis is a continuous health threat for residents, tourists and members of an international research community. Here we report the results of screening a tropical forest assemblage of sand fly species for infection by both Leishmania and a microbe that can potentially serve in vector population control, the cytoplasmically transmitted rickettsia, Wolbachia pipientis. Knowing accurately which Lutzomyia species are present, what their evolutionary relationships are, and how they are infected by strains of both Leishmania and Wolbachia is of critical value for building strategies to mitigate the impact of this disease in humans.We collected, sorted and then used DNA sequences to determine the diversity and probable phylogenetic relationships of the Phlebotominae occurring in the understory of Barro Colorado Island in the Republic of Panama. Sequence from CO1, the DNA barcoding gene, supported 18 morphology-based species determinations while revealing the presence of two possible "cryptic" species, one (Lu. sp. nr vespertilionis within the Vespertilionis group, the other (Lu. gomezi within the Lutzomyia-cruciata series. Using ITS-1 and "minicircle" primers we detected Leishmania DNA in 43.3% of Lu. trapidoi, 26.3% of Lu. gomezi individuals and in 0% of the other 18 sand fly species. Identical ITS-1 sequence was obtained from the Leishmania infecting Lu. trapidoi and Lu. gomezi, sequence which was 93% similar to Leishmania (viannia naiffi in GenBank, a species previously unknown in Panama, but recognized as a type of cutaneous leishmaniasis vectored broadly across northern and central South America. Distinct strains of the intracellular bacterium Wolbachia were detected in three of 20 sand fly species, including Lu. trapidoi

Species structure of sand fly (Diptera: Psychodidae fauna in the Brazilian western Amazon

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Luiz Herman Soares Gil

2009-11-01

Full Text Available We surveyed areas of the state of Rondônia in western Amazon for phlebotomine, which are potential vectors of leishmaniasis. A total of 5,998 specimens were captured, resulting in the identification of 48 species within the Lutzomyia (99.98% and Brumptomyia (0.02% genera. The predominant species was Lutzomyia davisi, followed by Lutzomyia umbratilis, Lutzomyia llanosmartinsi, Lutzomyia c. carrerai, Lutzomyia dendrophyla, Lutzomyia nevesi and Lutzomyia whitmani. All sand flies identified as vectors for cutaneous leishmaniasis in Brazil, i.e., Lu. davisi, Lu. umbratilis, Lu. c. carrerai and Lu. whitmani, were found in the surveyed areas.

Studies on the sand fly fauna (Diptera: Psychodidae) in high-transmission areas of cutaneous leishmaniasis in the Republic of Suriname

NARCIS (Netherlands)

Kent, Alida D.; Dos Santos, Thiago V.; Gangadin, Anielkoemar; Samjhawan, Ashok; Mans, Dennis R. A.; Schallig, Henk D. F. H.

2013-01-01

Sand flies (Diptera: Psychodidae) are the vectors of Leishmania parasites, the causative agents of leishmaniasis. Cutaneous leishmaniasis is an increasing public health problem in the Republic of Suriname and is mainly caused by Leishmania (Vianna) guyanensis, but L. (V.) braziliensis, L. (L.)

Numerical simulation of fly-ash transport in three sands of different particle-size distributions using HYDRUS-1D

Czech Academy of Sciences Publication Activity Database

Kodešová, R.; Kapička, Aleš; Lebeda, J.; Grison, Hana; Kočárek, M.; Petrovský, Eduard

2011-01-01

Roč. 59, č. 3 (2011), s. 206-216 ISSN 0042-790X R&D Projects: GA AV ČR IAA300120701 Institutional research plan: CEZ:AV0Z30120515 Keywords : sand * fly-ash migration * magnetic susceptibility * numerical simulation * attachment /detachment concept * filtration theory Subject RIV: DK - Soil Contamination ; De-contamination incl. Pesticides Impact factor: 0.340, year: 2011

Acetylcholinesterase of the Sand Fly, Phlebotomus papatasi (Scopoli): cDNA Sequence, Baculovirus Expression, and Biochemical Properties

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2013-01-01

Iraq: 6. Evaluation of insecticides for the control of sand flies. J Med Entomol 2011, 48:584–599. 16. Hemingway J, Ranson H: Insecticide resistance...leishmaniasis in Morocco. Parasit Vectors 2012, 5:51. 18. Surendran SN, Karunaratne SHPP, Adams Z, Hemingway J, Hawkes NJ: Molecular and biochemical...2002, 37:213–218. 45. Vontas JG, Hejazi MJ, Hawkes NJ, Cosmidis N, Loukas M, Hemingway J: Resistance-associated point mutations of organophosphate

Diagnostic doses and times for Phlebotomus papatasi and Lutzomyia longipalpis sand flies (Diptera: Psychodidae: Phlebotominae) using the CDC bottle bioassay to assess insecticide resistance.

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Denlinger, David S; Creswell, Joseph A; Anderson, J Laine; Reese, Conor K; Bernhardt, Scott A

2016-04-15

Insecticide resistance to synthetic chemical insecticides is a worldwide concern in phlebotomine sand flies (Diptera: Psychodidae), the vectors of Leishmania spp. parasites. The CDC bottle bioassay assesses resistance by testing populations against verified diagnostic doses and diagnostic times for an insecticide, but the assay has been used limitedly with sand flies. The objective of this study was to determine diagnostic doses and diagnostic times for laboratory Lutzomyia longipalpis (Lutz & Nieva) and Phlebotomus papatasi (Scopoli) to ten insecticides, including pyrethroids, organophosphates, carbamates, and DDT, that are used worldwide to control vectors. Bioassays were conducted in 1,000-ml glass bottles each containing 10-25 sand flies from laboratory colonies of L. longipalpis or P. papatasi. Four pyrethroids, three organophosphates, two carbamates and one organochlorine, were evaluated. A series of concentrations were tested for each insecticide, and four replicates were conducted for each concentration. Diagnostic doses were determined only during the exposure bioassay for the organophosphates and carbamates. For the pyrethroids and DDT, diagnostic doses were determined for both the exposure bioassay and after a 24-hour recovery period. Both species are highly susceptible to the carbamates as their diagnostic doses are under 7.0 μg/ml. Both species are also highly susceptible to DDT during the exposure assay as their diagnostic doses are 7.5 μg/ml, yet their diagnostic doses for the 24-h recovery period are 650.0 μg/ml for Lu. longipalpis and 470.0 μg/ml for P. papatasi. Diagnostic doses and diagnostic times can now be incorporated into vector management programs that use the CDC bottle bioassay to assess insecticide resistance in field populations of Lu. longipalpis and P. papatasi. These findings provide initial starting points for determining diagnostic doses and diagnostic times for other sand fly vector species and wild populations using the CDC

Estimating carrying capacity in a newly colonized sand fly Lutzomyia serrana (Diptera: Psychodidae).

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Santamaría, Erika; Munstermann, Leonard E; Ferro, Cristina

2002-02-01

The phlebotomine sand fly Lutzomyia serrana (Damasceno & Arouck) was mass-reared tinder conditions of varying densities in an effort to improve colony production efficiency. To do this, the experimental carrying capacity of a standard rearing chamber was determined, i.e., the optimum population size in relation to density (individuals per unit of space). Rearing chambers of 100 cm3 were populated with 1-50 L. serrana engorged females and an equal number of males. Laboratory conditions were maintained at 23-26 degrees C and 85-95% RH. The following parameters were recorded for each experimental chamber (three replicates): (1) female mortality without oviposition, (2) number of eggs oviposited and (3) number of adults emerging from the egg cohort. Female mortality began to increase substantially in the 26-female chamber, from 5.7% to 15% and finally reaching 60.2% in the 46-50 female chambers. In the chambers containing 1-20 females, egg number and realized adult progeny increased linearly to reach an asymptote. In the 20-50 female chambers, the number of eggs ranged from 420 to 699, and adult production from 306 to 432. The optimum carrying capacity for the 100-cm3 chambers was 22 +/- 2 females. Beyond this number, auto-regulation was initiated, i.e., female mortality without oviposition increased as the number of females per chamber increased. Total number of eggs and adult production was similar in all chambers containing 20-50 females. In conclusion, for optimizing production of mass reared sand flies, determination of the carrying capacity is essential to optimize use of insectary resources, to avoid loss of valuable potentially ovipositing females, and to increase overall production efficiency.

Measurement of recent exposure to Phlebotomus argentipes, the vector of Indian visceral Leishmaniasis, by using human antibody responses to sand fly saliva.

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Clements, Meredith F; Gidwani, Kamlesh; Kumar, Rajiv; Hostomska, Jitka; Dinesh, Diwakar S; Kumar, Vijay; Das, Pradeep; Müller, Ingrid; Hamilton, Gordon; Volfova, Vera; Boelaert, Marleen; Das, Murari; Rijal, Suman; Picado, Albert; Volf, Petr; Sundar, Shyam; Davies, Clive R; Rogers, Matthew E

2010-05-01

Antibody (IgG) responses to the saliva of Phlebotomus argentipes were investigated using serum samples from regions of India endemic and non-endemic for visceral leishmaniasis (VL). By pre-adsorbing the sera against the saliva of the competing human-biting but non-VL vector P. papatasi, we significantly improved the specificity of a P. argentipes saliva enzyme-linked immunosorbent assay. Using this method, we observed a statistically significant correlation between antibodies to P. argenitpes saliva and the average indoor density of female sand flies. Additionally, the method was able to detect recent changes in vector exposure when sera from VL patients were assayed before, during, and after hospitalization and protected from sand fly bites under untreated bed nets. Collectively, these results highlight the utility of antibodies to P. argentipes saliva as an important tool to evaluate VL vector control programs.

Differential Midgut Attachment of Leishmania (Viannia braziliensis in the Sand Flies Lutzomyia (Nyssomyia whitmani and Lutzomyia (Nyssomyia intermedia

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Rodrigo P. Soares

2010-01-01

Full Text Available The interaction between Leishmania and sand flies has been demonstrated in many Old and New World species. Besides the morphological differentiation from procyclic to infective metacyclic promastigotes, the parasite undergoes biochemical transformations in its major surface lipophosphoglycan (LPG. An upregulation of β-glucose residues was previously shown in the LPG repeat units from procyclic to metacyclic phase in Leishmania (Viannia braziliensis, which has not been reported in any Leishmania species. LPG has been implicated as an adhesion molecule that mediates the interaction with the midgut epithelium of the sand fly in the Subgenus Leishmania. These adaptations were explored for the first time in a species from the Subgenus Viannia, L. (V. braziliensis with its natural vectors Lutzomyia (Nyssomyia intermedia and Lutzomyia (Nyssomyia whitmani. Using two in vitro binding techniques, phosphoglycans (PGs derived from procyclic and metacyclic parasites were able to bind to the insect midgut and inhibit L. braziliensis attachment. Interestingly, L. braziliensis procyclic parasite attachment was ∼11-fold greater in the midgut of L. whitmani than in L. intermedia. The epidemiological relevance of L. whitmani as a vector of American Cutaneous Leishmaniasis (ACL in Brazil is discussed.

Cross-species genetic exchange between visceral and cutaneous strains of Leishmania in the sand fly vector.

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Romano, Audrey; Inbar, Ehud; Debrabant, Alain; Charmoy, Melanie; Lawyer, Phillip; Ribeiro-Gomes, Flavia; Barhoumi, Mourad; Grigg, Michael; Shaik, Jahangheer; Dobson, Deborah; Beverley, Stephen M; Sacks, David L

2014-11-25

Genetic exchange between Leishmania major strains during their development in the sand fly vector has been experimentally shown. To investigate the possibility of genetic exchange between different Leishmania species, a cutaneous strain of L. major and a visceral strain of Leishmania infantum, each bearing a different drug-resistant marker, were used to coinfect Lutzomyia longipalpis sand flies. Eleven double-drug-resistant progeny clones, each the product of an independent mating event, were generated and submitted to genotype and phenotype analyses. The analysis of multiple allelic markers across the genome suggested that each progeny clone inherited at least one full set of chromosomes from each parent, with loss of heterozygosity at some loci, and uniparental retention of maxicircle kinetoplast DNA. Hybrids with DNA contents of approximately 2n, 3n, and 4n were observed. In vivo studies revealed clear differences in the ability of the hybrids to produce pathology in the skin or to disseminate to and grow in the viscera, suggesting polymorphisms and differential inheritance of the gene(s) controlling these traits. The studies, to our knowledge, represent the first experimental confirmation of cross-species mating in Leishmania, opening the way toward genetic linkage analysis of important traits and providing strong evidence that genetic exchange is responsible for the generation of the mixed-species genotypes observed in natural populations.

Leishmania infantum nicotinamidase is required for late-stage development in its natural sand fly vector, Phlebotomus perniciosus

OpenAIRE

Gazanion, Elodie; Seblova, V.; Votypka, J.; Vergnes, Baptiste; Garcia, Deborah; Volf, P.; Sereno, Denis

2012-01-01

Leishmania infantum nicotinamidase, encoded by the Lipnc1 gene, converts nicotinamide into nicotinic acid to ensure Nicotinamide-Adenine-Dinucleotide (NAD(+)) biosynthesis. We were curious to explore the role of this enzyme during L infantum development in its natural sand fly vector, Phlebotomus perniciosus (Diptera, Phlebotominae), using null mutants with a deleted Lipnc1 gene. The null mutants developed as well as the wild type L infantum at the early time points post their ingestion withi...

Leishmania in sand flies: comparison of quantitative polymerase chain reaction with other techniques to determine the intensity of infection

Czech Academy of Sciences Publication Activity Database

Myšková, J.; Votýpka, Jan; Volf, P.

2008-01-01

Roč. 45, č. 1 (2008), s. 133-138 ISSN 0022-2585 R&D Projects: GA MŠk(CZ) LC06009 Grant - others:Univerzita Karlova v Praze(CZ) 195/2005/B-BIO/PrF Institutional research plan: CEZ:AV0Z60220518 Keywords : sand fly * Leishmania * Phlebotomus * parasite-vector interaction * RT-PCR Subject RIV: EG - Zoology Impact factor: 1.967, year: 2008

Phylogenetics of the Phlebotomine Sand Fly Group Verrucarum (Diptera: Psychodidae: Lutzomyia)

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Cohnstaedt, Lee W.; Beati, Lorenza; Caceres, Abraham G.; Ferro, Cristina; Munstermann, Leonard E.

2011-01-01

Within the sand fly genus Lutzomyia, the Verrucarum species group contains several of the principal vectors of American cutaneous leishmaniasis and human bartonellosis in the Andean region of South America. The group encompasses 40 species for which the taxonomic status, phylogenetic relationships, and role of each species in disease transmission remain unresolved. Mitochondrial cytochrome c oxidase I (COI) phylogenetic analysis of a 667-bp fragment supported the morphological classification of the Verrucarum group into series. Genetic sequences from seven species were grouped in well-supported monophyletic lineages. Four species, however, clustered in two paraphyletic lineages that indicate conspecificity—the Lutzomyia longiflocosa–Lutzomyia sauroida pair and the Lutzomyia quasitownsendi–Lutzomyia torvida pair. COI sequences were also evaluated as a taxonomic tool based on interspecific genetic variability within the Verrucarum group and the intraspecific variability of one of its members, Lutzomyia verrucarum, across its known distribution. PMID:21633028

Phylogenetics of the phlebotomine sand fly group Verrucarum (Diptera: Psychodidae: Lutzomyia).

Science.gov (United States)

Cohnstaedt, Lee W; Beati, Lorenza; Caceres, Abraham G; Ferro, Cristina; Munstermann, Leonard E

2011-06-01

Within the sand fly genus Lutzomyia, the Verrucarum species group contains several of the principal vectors of American cutaneous leishmaniasis and human bartonellosis in the Andean region of South America. The group encompasses 40 species for which the taxonomic status, phylogenetic relationships, and role of each species in disease transmission remain unresolved. Mitochondrial cytochrome c oxidase I (COI) phylogenetic analysis of a 667-bp fragment supported the morphological classification of the Verrucarum group into series. Genetic sequences from seven species were grouped in well-supported monophyletic lineages. Four species, however, clustered in two paraphyletic lineages that indicate conspecificity--the Lutzomyia longiflocosa-Lutzomyia sauroida pair and the Lutzomyia quasitownsendi-Lutzomyia torvida pair. COI sequences were also evaluated as a taxonomic tool based on interspecific genetic variability within the Verrucarum group and the intraspecific variability of one of its members, Lutzomyia verrucarum, across its known distribution.

Description of Lutzomyia bianchigalatiae n. sp. A sand fly within the subgenus Pintomyia Costa Lima 1932 (Diptera; Psychodidae).

Science.gov (United States)

Andrade Filho, J D; Aguiar, G M; Dias, E S; Falcão, A L

1999-01-01

A new sand fly species is described based on males collected in Bananal, municipality of Mariana and the female from Sabará city, State of Minas Gerais, Brazil. Taxonomic remarks, geographic distribution and the description of new species are presented. The name Lutzomyia (Pintomyia) bianchigalatiae is in honour of Dr Eunice Aparecida Bianchi Galati, friend and researcher at the Faculdade de Saúde Pública, Universidade de São Paulo.

A study of fine aggregate replacement with fly ash an environmental friendly and economical solution.

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Pofale, A D; Deo, S V

2010-10-01

The use of fly ash as a replacement of sand has a great potential to benefit our society in terms of reducing demand of natural sand, reducing environmental problems, conserving energy and reducing landfill area requirement. This paper presents an approach to increase the utilization of fly ash and conserve scarcely available natural sand for sustainable development. The experimental investigation by the inclusion of fly ash as a partial replacement of sand as compared to control cement mortar mixes indicated 50% to 100% increase in the compressive strength of mortar at 91 days. Replacement of 50% sand with fly ash can save about 0.4 m3 sand. Comparison of cost per N/mm2 compressive strength has shown about 40% to 60% saving in cost. Based on the experimental results, correlations are developed for finding out the compressive strength and cost at 28 and 91 days. Sand was replaced with 10% to 50% of fly ash by weight and 0.5, 0.55, 0.6 and 0.65 W/C ratios were used. Flow test performed for mortar revealed that as the percentage replacement of sand with the fly ash increased the flow of the mortar decreased. It was also observed that wet and dry densities were more than the control mortar for 10% & 20% replacement of sand with fly ash but for higher replacement percentage density reduced marginally.

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

OpenAIRE

Philippe Rispail; Jacques Dereure; Daniel Jarry

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...

Phlebotominae sand flies (Diptera: Psychodidae): potential vectors of American cutaneous leishmaniasis agents in the area associated with the Santo Antônio Hydroelectric System in Western Amazonian Brazil.

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Galardo, Allan Kardec Ribeiro; Galardo, Clícia Denis; Silveira, Guilherme Abbad; Ribeiro, Kaio Augusto Nabas; Hijjar, Andréa Valadão; Oliveira, Liliane Leite; Dos Santos, Thiago Vasconcelos

2015-01-01

An entomological study was conducted as part of a vector-monitoring program in the area associated with the Santo Antônio hydroelectric system in State of Rondônia, Western Amazonian Brazil. Fourteen sampling sites were surveyed to obtain data on the potential vectors of Leishmania spp. in the area. Sand flies were collected from 2011 to 2014 during the months of January/February (rainy season), May/June (dry season), and September/October (intermediary season) using light traps arranged in three vertical strata (0.5, 1, and 20m). A total of 7,575 individuals belonging to 62 species/subspecies were collected. The five most frequently collected sand flies were Psychodopygus davisi (Root) (36.67%), Trichophoromyia ubiquitalis (Mangabeira) (8.51%), Nyssomyia umbratilis (Ward & Fraiha) (6.14%), Bichromomyia flaviscutellata (Mangabeira) (5.74%), and Psychodopygus complexus (Mangabeira) (5.25%). These species have been implicated in the transmission of American cutaneous leishmaniasis agents in the Brazilian Amazon region and described as potential vectors of this disease in the study area. Additional surveillance is needed, especially in areas where these five species of sand fly are found.

Phlebotominae sand flies (Diptera: Psychodidae: potential vectors of American cutaneous leishmaniasis agents in the area associated with the Santo Antônio Hydroelectric System in Western Amazonian Brazil

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Allan Kardec Ribeiro Galardo

2015-06-01

Full Text Available INTRODUCTION: An entomological study was conducted as part of a vector-monitoring program in the area associated with the Santo Antônio hydroelectric system in State of Rondônia, Western Amazonian Brazil. METHODS: Fourteen sampling sites were surveyed to obtain data on the potential vectors of Leishmania spp. in the area. Sand flies were collected from 2011 to 2014 during the months of January/February (rainy season, May/June (dry season, and September/October (intermediary season using light traps arranged in three vertical strata (0.5, 1, and 20m. RESULTS : A total of 7,575 individuals belonging to 62 species/subspecies were collected. The five most frequently collected sand flies were Psychodopygus davisi (Root (36.67%, Trichophoromyia ubiquitalis (Mangabeira (8.51%, Nyssomyia umbratilis (Ward & Fraiha (6.14%, Bichromomyia flaviscutellata (Mangabeira (5.74%, and Psychodopygus complexus (Mangabeira (5.25%. These species have been implicated in the transmission of American cutaneous leishmaniasis agents in the Brazilian Amazon region and described as potential vectors of this disease in the study area. CONCLUSIONS: Additional surveillance is needed, especially in areas where these five species of sand fly are found.

The mating competence of geographically diverse Leishmania major strains in their natural and unnatural sand fly vectors.

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Inbar, Ehud; Akopyants, Natalia S; Charmoy, Melanie; Romano, Audrey; Lawyer, Phillip; Elnaiem, Dia-Eldin A; Kauffmann, Florence; Barhoumi, Mourad; Grigg, Michael; Owens, Katherine; Fay, Michael; Dobson, Deborah E; Shaik, Jahangheer; Beverley, Stephen M; Sacks, David

2013-01-01

Invertebrate stages of Leishmania are capable of genetic exchange during their extracellular growth and development in the sand fly vector. Here we explore two variables: the ability of diverse L. major strains from across its natural range to undergo mating in pairwise tests; and the timing of the appearance of hybrids and their developmental stage associations within both natural (Phlebotomus duboscqi) and unnatural (Lutzomyia longipalpis) sand fly vectors. Following co-infection of flies with parental lines bearing independent drug markers, doubly-drug resistant hybrid progeny were selected, from which 96 clonal lines were analyzed for DNA content and genotyped for parent alleles at 4-6 unlinked nuclear loci as well as the maxicircle DNA. As seen previously, the majority of hybrids showed '2n' DNA contents, but with a significant number of '3n' and one '4n' offspring. In the natural vector, 97% of the nuclear loci showed both parental alleles; however, 3% (4/150) showed only one parental allele. In the unnatural vector, the frequency of uniparental inheritance rose to 10% (27/275). We attribute this to loss of heterozygosity after mating, most likely arising from aneuploidy which is both common and temporally variable in Leishmania. As seen previously, only uniparental inheritance of maxicircle kDNA was observed. Hybrids were recovered at similar efficiencies in all pairwise crosses tested, suggesting that L. major lacks detectable 'mating types' that limit free genetic exchange. In the natural vector, comparisons of the timing of hybrid formation with the presence of developmental stages suggest nectomonads as the most likely sexually competent stage, with hybrids emerging well before the first appearance of metacyclic promastigotes. These studies provide an important perspective on the prevalence of genetic exchange in natural populations of L. major and a guide for experimental studies to understand the biology of mating.

Ecuador Paraiso Escondido Virus, a New Flavivirus Isolated from New World Sand Flies in Ecuador, Is the First Representative of a Novel Clade in the Genus Flavivirus.

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Alkan, Cigdem; Zapata, Sonia; Bichaud, Laurence; Moureau, Grégory; Lemey, Philippe; Firth, Andrew E; Gritsun, Tamara S; Gould, Ernest A; de Lamballerie, Xavier; Depaquit, Jérôme; Charrel, Rémi N

2015-12-01

A new flavivirus, Ecuador Paraiso Escondido virus (EPEV), named after the village where it was discovered, was isolated from sand flies (Psathyromyia abonnenci, formerly Lutzomyia abonnenci) that are unique to the New World. This represents the first sand fly-borne flavivirus identified in the New World. EPEV exhibited a typical flavivirus genome organization. Nevertheless, the maximum pairwise amino acid sequence identity with currently recognized flaviviruses was 52.8%. Phylogenetic analysis of the complete coding sequence showed that EPEV represents a distinct clade which diverged from a lineage that was ancestral to the nonvectored flaviviruses Entebbe bat virus, Yokose virus, and Sokoluk virus and also the Aedes-associated mosquito-borne flaviviruses, which include yellow fever virus, Sepik virus, Saboya virus, and others. EPEV replicated in C6/36 mosquito cells, yielding high infectious titers, but failed to reproduce either in vertebrate cell lines (Vero, BHK, SW13, and XTC cells) or in suckling mouse brains. This surprising result, which appears to eliminate an association with vertebrate hosts in the life cycle of EPEV, is discussed in the context of the evolutionary origins of EPEV in the New World. The flaviviruses are rarely (if ever) vectored by sand fly species, at least in the Old World. We have identified the first representative of a sand fly-associated flavivirus, Ecuador Paraiso Escondido virus (EPEV), in the New World. EPEV constitutes a novel clade according to current knowledge of the flaviviruses. Phylogenetic analysis of the virus genome showed that EPEV roots the Aedes-associated mosquito-borne flaviviruses, including yellow fever virus. In light of this new discovery, the New World origin of EPEV is discussed together with that of the other flaviviruses. Copyright © 2015 Alkan et al.

Description of the female of the Peruvian sand fly Lutzomyia reclusa (Diptera: Psychodidae: Phlebotominae).

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Ibáñez-Bernal, Sergio; Cáceres, Abraham G

2011-03-01

The female of the phlebotomine sand fly Lutzomyia reclusa Fernández & Rogers 1991 [= Pintomyia (Pifanomyia) reclusa (Fernández & Rogers) sensu Galati], is described for the first time, based on specimens collected in the Department of Cajamarca, in northern Peru. The female can be recognized from other species of the series pia, species group Verrucarum, by wing venation with beta shorter than half of alpha, labrum just shorter than head width but longer than flagellomere 1, palpomere 5 much longer than palpomere 3, arrangement of cibarial armature, and form of spermathecae and relative size of spermathecal ducts. Diagnostic characters and measurements of the male of Lu. reclusa are provided as well.

Eradicating tsetse flies: Senegal nears first victory

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Dixit, Aabha

2015-01-01

After a four-year eradication programme including nuclear techniques, the Niayes region of Senegal is now almost free of the tsetse fly, which used to decimate livestock. “I have not seen a single tsetse fly for a year now,” said cattle farmer Oumar Sow. “This is in contrast to earlier, when they increased in numbers, especially during the cold season. The flies were really a nuisance to our animals and we had to carefully select the time for milking. Now, there is no problem with that.” The tsetse fly is a bloodsucking insect that kills more than three million livestock in sub-Saharan Africa every year, costing the agriculture industry more than US $4 billion annually. The tsetse fly transmits parasites that cause a wasting disease called nagana in cattle. In some parts of Africa the fly also causes over 75 000 cases of human ‘sleeping sickness’, which affects the central nervous system, and causes disorientation, personality changes, slurred speech, seizures, difficulty walking and talking, and ultimately death.

Genetic differentiation over a small spatial scale of the sand fly Lutzomyia vexator (Diptera: Psychodidae).

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Neal, Allison T; Ross, Max S; Schall, Jos J; Vardo-Zalik, Anne M

2016-10-18

The geographic scale and degree of genetic differentiation for arthropod vectors that transmit parasites play an important role in the distribution, prevalence and coevolution of pathogens of human and wildlife significance. We determined the genetic diversity and population structure of the sand fly Lutzomyia vexator over spatial scales from 0.56 to 3.79 km at a study region in northern California. The study was provoked by observations of differentiation at fine spatial scales of a lizard malaria parasite vectored by Lu. vexator. A microsatellite enrichment/next-generation sequencing protocol was used to identify variable microsatellite loci within the genome of Lu. vexator. Alleles present at these loci were examined in four populations of Lu. vexator in Hopland, CA. Population differentiation was assessed using Fst and D (of Cavalli-Sforza and Edwards), and the program Structure was used to determine the degree of subdivision present. The effective population size for the sand fly populations was also calculated. Eight microsatellite markers were characterized and revealed high genetic diversity (uHe = 0.79-0.92, Na = 12-24) and slight but significant differentiation across the fine spatial scale examined (average pairwise D = 0.327; F ST  = 0.0185 (95 % bootstrapped CI: 0.0102-0.0264). Even though the insects are difficult to capture using standard methods, the estimated population size was thousands per local site. The results argue that Lu. vexator at the study sites are abundant and not highly mobile, which may influence the overall transmission dynamics of the lizard malaria parasite, Plasmodium mexicanum, and other parasites transmitted by this species.

Survey of sand flies (Diptera: Psychodidae in an environmentally protected area in Brazil.

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Lara Saraiva

Full Text Available Brazil is one of the most important endemic areas for leishmaniasis worldwide. Protected areas that are tourist attractions likely present an important risk of transmission of cutaneous leishmaniasis (CL. Furthermore, with the geographical expansion of visceral leishmaniasis (VL, several studies have recorded the occurrence of its vector, Lutzomyia longipalpis, and cases of human and canine VL in such tourist areas. The Parque Estadual do Sumidouro is an environmentally protected area located in the Brazilian Cerrado biome and in an important area endemic for leishmaniasis in the state of Minas Gerais. The purpose of this study was to monitor the sand fly fauna in areas of tourist activity in the park. Sampling was performed every month, from September 2011 to August 2013, using CDC light traps at six sites of differing environmental characteristics. Sampled specimens were identified following Galati (2003, and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A total of 4,675 sand fly specimens of 25 species belonging to nine genera were collected. The most abundant species were Micropygomyia quinquefer, Lutzomyia renei and Pintomyia pessoai, although only Pi. pessoai is implicated in the transmission of Leishmania braziliensis. The species accumulation curve reached saturation on the 16th sampling event. Species richness, diversity and evenness differed among the sampled areas. The seasonal curve was not determined by a single unique species, and no single species was the most abundant in all environments sampled. The main vector of Leishmania (Leishmania infantum, Lutzomyia longipalpis, accounted for only 5.35% of the specimens collected. Proven or suspected vectors of Leishmania (Viannia braziliensis were recorded, and one female of the cortellezzii complex tested positive for Le. braziliensis DNA. Even with a low infection rate (0.62%, these data indicate the circulation of the parasite

Phlebotomine sand fly survey in the focus of leishmaniasis in Madrid, Spain (2012-2014): seasonal dynamics, Leishmania infantum infection rates and blood meal preferences.

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González, Estela; Jiménez, Maribel; Hernández, Sonia; Martín-Martín, Inés; Molina, Ricardo

2017-08-01

An unusual increase of human leishmaniasis cases due to Leishmania infantum is occurring in an urban area of southwestern Madrid, Spain, since 2010. Entomological surveys have shown that Phlebotomus perniciosus is the only potential vector. Direct xenodiagnosis in hares (Lepus granatensis) and rabbits (Oryctolagus cuniculus) collected in the focus area proved that they can transmit parasites to colonized P. perniciosus. Isolates were characterized as L. infantum. The aim of the present work was to conduct a comprehensive study of sand flies in the outbreak area, with special emphasis on P. perniciosus. Entomological surveys were done from June to October 2012-2014 in 4 stations located close to the affected area. Twenty sticky traps (ST) and two CDC light traps (LT) were monthly placed during two consecutive days in every station. LT were replaced every morning. Sand fly infection rates were determined by dissecting females collected with LT. Molecular procedures applied to study blood meal preferences and to detect L. infantum were performed for a better understanding of the epidemiology of the outbreak. A total of 45,127 specimens belonging to 4 sand fly species were collected: P. perniciosus (75.34%), Sergentomyia minuta (24.65%), Phlebotomus sergenti (0.005%) and Phlebotomus papatasi (0.005%). No Phlebotomus ariasi were captured. From 3203 P. perniciosus female dissected, 117 were infected with flagellates (3.7%). Furthermore, 13.31% and 7.78% of blood-fed and unfed female sand flies, respectively, were found infected with L. infantum by PCR. The highest rates of infected P. perniciosus were detected at the end of the transmission periods. Regarding to blood meal preferences, hares and rabbits were preferred, although human, cat and dog blood were also found. This entomological study highlights the exceptional nature of the Leishmania outbreak occurring in southwestern Madrid, Spain. It is confirmed that P. perniciosus is the only vector in the affected area

Identification of phlebotomine sand flies using one MALDI-TOF MS reference database and two mass spectrometer systems.

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Mathis, Alexander; Depaquit, Jérôme; Dvořák, Vit; Tuten, Holly; Bañuls, Anne-Laure; Halada, Petr; Zapata, Sonia; Lehrter, Véronique; Hlavačková, Kristýna; Prudhomme, Jorian; Volf, Petr; Sereno, Denis; Kaufmann, Christian; Pflüger, Valentin; Schaffner, Francis

2015-05-10

Rapid, accurate and high-throughput identification of vector arthropods is of paramount importance in surveillance programmes that are becoming more common due to the changing geographic occurrence and extent of many arthropod-borne diseases. Protein profiling by MALDI-TOF mass spectrometry fulfils these requirements for identification, and reference databases have recently been established for several vector taxa, mostly with specimens from laboratory colonies. We established and validated a reference database containing 20 phlebotomine sand fly (Diptera: Psychodidae, Phlebotominae) species by using specimens from colonies or field-collections that had been stored for various periods of time. Identical biomarker mass patterns ('superspectra') were obtained with colony- or field-derived specimens of the same species. In the validation study, high quality spectra (i.e. more than 30 evaluable masses) were obtained with all fresh insects from colonies, and with 55/59 insects deep-frozen (liquid nitrogen/-80 °C) for up to 25 years. In contrast, only 36/52 specimens stored in ethanol could be identified. This resulted in an overall sensitivity of 87 % (140/161); specificity was 100 %. Duration of storage impaired data counts in the high mass range, and thus cluster analyses of closely related specimens might reflect their storage conditions rather than phenotypic distinctness. A major drawback of MALDI-TOF MS is the restricted availability of in-house databases and the fact that mass spectrometers from 2 companies (Bruker, Shimadzu) are widely being used. We have analysed fingerprints of phlebotomine sand flies obtained by automatic routine procedure on a Bruker instrument by using our database and the software established on a Shimadzu system. The sensitivity with 312 specimens from 8 sand fly species from laboratory colonies when evaluating only high quality spectra was 98.3 %; the specificity was 100 %. The corresponding diagnostic values with 55 field

Posterior spiracles of fourth instar larvae of four species of phlebotomine sand flies (Diptera: Psychodidae under scanning electron microscopy

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Pessoa Felipe Arley Costa

2000-01-01

Full Text Available In the present study, posterior spiracles of laboratory-reared fourth instar larvae of Lutzomyia longipalpis, L. migonei, L. lenti, and L. whitmani (Diptera: Psychodidae of the State of Ceará, Brazil, were examined under scanning electron microscopy. The number of papillae of spiracles examined varied according to the species examined, but no intraspecific differences were found. The importance of this structure to sand fly larva identification and phylogeny is commented.

Studies on sand fly fauna and ecological analysis of Phlebotomus orientalis in the highland and lowland foci of kala-azar in northwestern Ethiopia.

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Esayas Aklilu

Full Text Available Visceral leishmaniasis (VL also known as kala-azar is a growing health problem in Ethiopia with an estimated annual VL incidence between 3700 and 7400. The disease is mainly endemic in northwestern parts of the country. The aim of the current study was to determine the sand fly fauna and ecology of Phlebotomus orientalis in two endemic and ecologically distinct areas of northwestern Ethiopia.Sand flies were collected using CDC light traps, sticky traps and pyrethrum spray catches from peri-domestic, mixed forest, farm field and indoor habitats from both Libo-Kemkem (May 2011-April 2012 and Metema (October 2012-September 2013 districts.A total of 51,411 sand fly specimens were collected and identified (10,776 from highland and 40, 635 from the lowland areas. Seven species were found in the highland area: two Phlebotomus spp. (P. orientalis and P. rodhaini and five Sergentomyia species. Whereas 19 species were found in the lowland area: six Phlebotomus (P. orientalis, P. rodhaini, P. bergeroti, P. duboscqi, P. papatasi and P. martini and 13 Sergentomyia species. Of the Phlebotomus spp., P. orientalis was the predominant species in both the highland (99.9% and lowland (93.7% areas. Indoor collections using pyrethrum spray catches and sticky traps indicated that P. orientalis has a strong exophilic and exophagic behaviors in both districts. In both areas, this species showed seasonal occurrence and showing abundance during the dry months (March-May/June of the year and increasing in numbers till the rain season, when numbers dropped dramatically. Mean density of P. orientalis in the two areas had positive and significant correlation with mean temperature in light trap collections (P0.05. Regarding the rainfall pattern, density of P. orientalis had negative and statistically insignificant correlation (for light trap collections for both areas and significant correlation (for sticky trap collections for lowland area.The current study indicated the

Description of Lutzomyia velezi, a new species of phlebotomine sand fly (Diptera: Psychodidae) from the Department of Antioquia, Colombia

OpenAIRE

Bejarano, Eduar Elías; Vivero, Rafael José; Uribe, Sandra

2010-01-01

The phlebotomine sand fly Lutzomyia velezi sp.nov. was described and illustrated from male specimens collected by light trap in the Reserva Natural Cañon del Río Claro in the Central Cordillera of the Colombian Andes. The new species belongs to the series sanguinaria of the subgenus Helcocyrtomyia, which is represented in Colombia by Lutzomyia cirrita, Lutzomyia hartmanni, Lutzomyia sanguinaria, Lutzomyia scorzai, Lutzomyia sp. of Pichindé and Lutzomyia tortura. The new species can be differe...

Experimental Study on Rise Husk Ash & Fly Ash Based Geo-Polymer Concrete Using M-Sand

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Nanda Kishore, G.; Gayathri, B.

2017-08-01

Serious environmental problems by means of increasing the production of Ordinary Portland cement (OPC), which is conventionally used as the primary binder to produce cement concrete. An attempt has been made to reduce the use of ordinary Portland cement in cement concrete. There is no standard mix design of geo-polymer concrete, an effort has been made to know the physical, chemical properties and optimum mix of geo-polymer concrete mix design. Concrete cubes of 100 x 100 x 100 mm were prepared and cured under steam curing for about 24 hours at temperature range of 40°C to 60°C. Fly ash is replaced partially with rice husk ash at percentage of 10%, 15% and 25%. Sodium hydroxide and sodium silicate are of used as alkaline activators with 5 Molar and 10 Molar NaOH solutions. Natural sand is replaced with manufacture sand. Test results were compared with controlled concrete mix of grade M30. The results shows that as the percentage of rice husk ash and water content increases, compressive strength will be decreases and as molarity of the alkaline solution increases, strength will be increases.

SAND FLIES (DIPTERA: PSYCHODIDAE) IN AN ENDEMIC AREA OF LEISHMANIASIS IN AQUIDAUANA MUNICIPALITY, PANTANAL OF MATO GROSSO DO SUL , BRAZIL

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de FIGUEIREDO, Helen Rezende; SANTOS, Mirella Ferreira da Cunha; CASARIL, Aline Etelvina; INFRAN, Jucelei Oliveira de Moura; RIBEIRO, Leticia Moraes; FERNANDES, Carlos Eurico dos Santos; de OLIVEIRA, Alessandra Gutierrez

2016-01-01

SUMMARY The Aquidauana municipality is considered an endemic area of leishmaniasis and an important tourist site in Mato Grosso do Sul State. The aim of this study was to investigate the sand fly fauna in the city of Aquidauana. Captures were carried out twice a month, from April 2012 to March 2014 with automatic light traps and active aspiration, in the peridomicile and domicile of six residences. A total of 9,338 specimens were collected, 3,179 and 6,159 using light traps and active aspiration, respectively. The fauna consisted of: Brumptomyia brumpti, Evandromyia aldafalcaoae, Ev. evandroi, Ev. lenti, Ev. orcyi, Ev. sallesi, Ev. termitophila, Ev. walkeri, Lutzomyia longipalpis and Psathyromyia bigeniculata. The most abundant species captured was Lutzomyia longipalpis, present in all the ecotopes, predominantly in peridomicile areas, and mainly males. Leishmania DNA was not detected in the insects. It was observed the abundance of the sand fly fauna in the region, as well as the high frequency of Lu. longipalpis, the main vector of L. infantum. The results of this study show the need to increase the monitoring and more effective control measures. It is noteworthy that the studied region presents several activities related to tourism and recreation, increasing the risk of transmission of leishmaniasis to this particular human population. PMID:27982353

Ecology of phlebotomine sand flies (Diptera: Psychodidaein a focus of Leishmania (Viannia brasiliensis in northeastern Colombia

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Bruce Alexander

1992-09-01

Full Text Available The phlebotomine sand fly fauna of two coffee plantations in a Leishmania-endemic area of Norte de Santander, Colombia was studied. Regular insect collections using a variety of methods were made for three and a half years. Information was obtained on diurnal resting sites, host range and seasonal abundance for 17 species, of wich five (Lutzomyia spinicrassa, Lu. serrana,Lu. shannoni, Lu. ovallesi and Lu. gomezi were far more numerous than the others, anthropophilic and present throughout the year. The behaviour of these and the remaining 12 species is discussed in relation to their potential role in transmission of Leishmania (Viannia brasiliensis in the area.

Molecular detection of Leishmania infection in sand flies in border line of Iran-Turkmenistan: restricted and permissive vectors.

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Bakhshi, H; Oshaghi, M A; Abai, M R; Rassi, Y; Akhavan, A A; Sheikh, Z; Mohtarami, F; Saidi, Z; Mirzajani, H; Anjomruz, M

2013-10-01

A molecular study was carried out to incriminate sand fly vectors of cutaneous leishmaniasis (CL) in rural areas of Sarakhs district, Khorassane-Razavi Province, northeastern Iran, in 2011. Sand flies of Sergentomyia with three species and Phlebotomus with six species respectively comprised 73.3% and 26.7% of the specimens. Phlebotomus papatasi was the most common Phlebotomine species in outdoor and indoor resting places. Leishmania infection was found at least in 17 (22%) specimens including Ph. papatasi (n=9 pool samples), Phlebotomus caucasicus (n=6), Phlebotomus alexandri (n=1), and Sergentomyia sintoni (n=1). The parasites were found comprised Leishmania major (n=5), Leishmania turanica (n=10), and Leishmania gerbilli (n=4). Infection of Ph. papatasi with both L. major and L. turanica supporting the new suggestion indicating that it is not restricted only with L. major. Circulation of L. major by Ph. alexandri, and both L. gerbilli and L. turanica by Ph. caucasicus, in addition to previous data indicating the ability of Ph. alexandri to circulate Leishmania infantum and Leishmania donovani, and Ph. caucasicus to circulate L. major, suggests that these two species can be permissive vectors. The results suggest that Ph. papatasi and Ph. alexandri are the primary and secondary vectors of CL where circulating L. major between human and reservoirs, whereas Ph. caucasicus is circulating L. turanica and L. gerbilli between the rodents in the region. Copyright © 2013 Elsevier Inc. All rights reserved.

New Insights Into the Transmissibility of Leishmania infantum From Dogs to Sand Flies: Experimental Vector-Transmission Reveals Persistent Parasite Depots at Bite Sites.

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Aslan, Hamide; Oliveira, Fabiano; Meneses, Claudio; Castrovinci, Philip; Gomes, Regis; Teixeira, Clarissa; Derenge, Candace A; Orandle, Marlene; Gradoni, Luigi; Oliva, Gaetano; Fischer, Laurent; Valenzuela, Jesus G; Kamhawi, Shaden

2016-06-01

Canine leishmaniasis (CanL) is a chronic fatal disease of dogs and a major source of human infection through propagation of parasites in vectors. Here, we infected 8 beagles through multiple experimental vector transmissions with Leishmania infantum-infected Lutzomyia longipalpis. CanL clinical signs varied, although live parasites were recovered from all dog spleens. Splenic parasite burdens correlated positively with Leishmania-specific interleukin 10 levels, negatively with Leishmania-specific interferon γ and interleukin 2 levels, and negatively with Leishmania skin test reactivity. A key finding was parasite persistence for 6 months in lesions observed at the bite sites in all dogs. These recrudesced following a second transmission performed at a distal site. Notably, sand flies efficiently acquired parasites after feeding on lesions at the primary bite site. In this study, controlled vector transmissions identify a potentially unappreciated role for skin at infectious bite sites in dogs with CanL, providing a new perspective regarding the mechanism of Leishmania transmissibility to vector sand flies. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

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

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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.

Transmission of Leishmania infantum in the Canine Leishmaniasis Focus of Mont-Rolland, Senegal: Ecological, Parasitological and Molecular Evidence for a Possible Role of Sergentomyia Sand Flies.

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Massila Wagué Senghor

2016-11-01

Full Text Available Leishmania (L. infantum is the causative agent in an endemic focus of canine leishmaniasis in the Mont-Rolland district (Thiès, Senegal. In this area, the transmission cycle is well established and more than 30% of dogs and 20% of humans are seropositive for L. infantum. However, the sand fly species involved in L. infantum transmission cycle are still unknown. Between 2007 and 2010, 3654 sand flies were collected from different environments (indoor, peridomestic, farming and sylvatic areas to identify the main L. infantum vector(s. Nine sand fly species were identified. The Phlebotomus genus (n = 54 specimens; Phlebotomus (Ph duboscqi and Phlebotomus (Ph. rodhaini was markedly under-represented in comparison to the Sergentomyia genus (n = 3600 specimens; Sergentomyia (Se adleri, Se. clydei, Se. antennata, Se. buxtoni, Se. dubia, Se. schwetzi and Se. magna. Se. dubia and Se. schwetzi were the dominant species indoor and in peridomestic environments, near humans and dogs. Blood-meal analysis indicated their anthropophilic behavior. Some Se. schwetzi specimens fed also on dogs. The dissection of females in the field allowed isolating L. infantum from sand flies of the Sergentomyia genus (0.4% of Se. dubia and 0.79% of Se. schwetzi females. It is worth noting that one Se. dubia female not engorged and not gravid revealed highly motile metacyclic of L. infantum in the anterior part of the midgut. PCR-based diagnosis and sequencing targeting Leishmania kinetoplast DNA (kDNA highlighted a high rate of L. infantum-positive females (5.38% of Se. dubia, 4.19% of Se. schwetzi and 3.64% of Se. magna. More than 2% of these positive females were unfed, suggesting the parasite survival after blood-meal digestion or egg laying. L. infantum prevalence in Se. schwetzi was associated with its seroprevalence in dogs and humans and L. infantum prevalence in Se. dubia was associated with its seroprevalence in humans. These evidences altogether strongly suggest that

Studies of Phlebotomine Sand Flies.

Science.gov (United States)

1981-05-01

al estudio de los Phlebotomus (Diptera: Psichodidae). Phlebotomus del grupo anthophorus en Guatemala. Rev. Colegio Mdd. Guatemala 22:187-193...studied in detail. A review of the North American Phiebotominae is in progress. Unclassie SECRIT CLASSFICTIO O TH PGE~ en om nteed 4[ AD_____ STUDIES OF...Diptera, Psychodidae) in Belize, Central America. Bull . Ent. Res. 65:595-599. Young, D.G. 1979. A review of the bloodsucking psychodid flies of Colombia

The characterization of the fat bodies and oenocytes in the adult females of the sand fly vectors Lutzomyia longipalpis and Phlebotomus papatasi.

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de Assis, Wiviane Alves; Malta, Juliana; Pimenta, Paulo Filemon P; Ramalho-Ortigão, José Marcelo; Martins, Gustavo Ferreira

2014-09-01

The fat body (FB) is responsible for the storage and synthesis of the majority of proteins and metabolites secreted into the hemolymph. Oenocytes are responsible for lipid processing and detoxification. The FB is distributed throughout the insect body cavity and organized as peripheral and perivisceral portions in the abdomen, with trophocytes and oenocytes attached to the peripheral portion. Here, we investigated the morphology and the subcellular changes in the peripheral and perivisceral FBs and in oenocytes of the sand flies Lutzomyia longipalpis and Phlebotomus papatasi after blood feeding. In L. longipalpis two-sized oenocytes (small and large) were identified, with both cell types displaying well-developed reticular system and smooth endoplasmic reticulum, whereas in P. papatasi, only small cells were observed. Detailed features of FBs of L. longipalpis and P. papatasi are shared either prior to or after blood feeding. The peripheral and perivisceral FBs responded to blood feeding with the development of glycogen zones and rough endoplasmic reticulum. This study provides the first detailed description of the FBs and oenocytes in sand flies, contributing significantly towards are better understanding of the biology of such important disease vectors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cattle Egret Bubulcus ibis interactions with large mammals in the ...

African Journals Online (AJOL)

behaviour on Cattle Egret numbers and distribution. Cattle Egrets ... Egret activity was classified as stationary, flying, foraging, or vigilant, while large mammal activity was .... ivLev v.s. 1961. Experimental ecology of the feeding of fishes.

Experimental Study on Superfine Sand Concrete Mixed by Double Mixing Technology

OpenAIRE

yuqing zhao

2013-01-01

Traditional concept thought that medium sand and fine sand can be used to mix concrete, superfine sand can not used to mix concrete. This makes the source of superfine sand limited. With the shortage of medium sand and fine sand, it is imperative to exploit the resource of superfine sand. Superfine sand concrete is mixed by means of Double-doped Technology-ultra-fine fly ash and super plasticizer. Primary factor influencing superfine sand concrete strength is studied by orthogonal test, the o...

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

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Philippe Rispail

2002-06-01

Full Text Available 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.

Spatial Distribution of Sand Fly Vectors and Eco-Epidemiology of Cutaneous Leishmaniasis Transmission in Colombia.

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Ferro, Cristina; López, Marla; Fuya, Patricia; Lugo, Ligia; Cordovez, Juan Manuel; González, Camila

2015-01-01

Leishmania is transmitted by Phlebotominae insects that maintain the enzootic cycle by circulating between sylvatic and domestic mammals; humans enter the cycles as accidental hosts due to the vector's search for blood source. In Colombia, leishmaniasis is an endemic disease and 95% of all cases are cutaneous (CL), these cases have been reported in several regions of the country where the intervention of sylvatic areas by the introduction of agriculture seem to have an impact on the rearrangement of new transmission cycles. Our study aimed to update vector species distribution in the country and to analyze the relationship between vectors' distribution, climate, land use and CL prevalence. A database with geographic information was assembled, and ecological niche modeling was performed to explore the potential distribution of each of the 21 species of medical importance in Colombia, using thirteen bioclimatic variables, three topographic and three principal components derived from NDVI. Binary models for each species were obtained and related to both land use coverage, and a CL prevalence map with available epidemiological data. Finally, maps of species potential distribution were summed to define potential species richness in the country. In total, 673 single records were obtained with Lutzomyia gomezi, Lutzomyia longipalpis, Psychodopygus panamensis, Psathyromyia shannoni and Pintomyia evansi the species with the highest number of records. Eighteen species had significant models, considering the area under the curve and the jackknife results: L. gomezi and P. panamensis had the widest potential distribution. All sand fly species except for Nyssomyia antunesi are mainly distributed in regions with rates of prevalence between 0.33 to 101.35 cases per 100,000 inhabitants and 76% of collection data points fall into transformed ecosystems. Distribution ranges of sand flies with medical importance in Colombia correspond predominantly to disturbed areas, where the

Phlebotomine Sand Fly Fauna and Leishmania Infection in the Vicinity of the Serra do Cipó National Park, a Natural Brazilian Heritage Site

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Lana, Rosana Silva; Michalsky, Érika Monteiro; Fortes-Dias, Consuelo Latorre; França-Silva, João Carlos; Lara-Silva, Fabiana de Oliveira; Lima, Ana Cristina Vianna Mariano da Rocha; Moreira de Avelar, Daniel; Martins, Juliana Cristina Dias; Dias, Edelberto Santos

2015-01-01

In the New World, the leishmaniases are primarily transmitted to humans through the bites of Leishmania-infected Lutzomyia (Diptera: Psychodidae) phlebotomine sand flies. Any or both of two basic clinical forms of these diseases are endemic to several cities in Brazil—the American cutaneous leishmaniasis (ACL) and the American visceral leishmaniasis (AVL). The present study was conducted in the urban area of a small-sized Brazilian municipality (Jaboticatubas), in which three cases of AVL and nine of ACL have been reported in the last five years. Jaboticatubas is an important tourism hub, as it includes a major part of the Serra do Cipó National Park. Currently, no local data is available on the entomological fauna or circulating Leishmania. During the one-year period of this study, we captured 3,104 phlebotomine sand flies belonging to sixteen Lutzomyia species. In addition to identifying incriminated or suspected vectors of ACL with DNA of the etiological agent of AVL and vice versa, we also detected Leishmania DNA in unexpected Lutzomyia species. The expressive presence of vectors and natural Leishmania infection indicates favorable conditions for the spreading of leishmaniases in the vicinity of the Serra do Cipó National Park. PMID:25793193

Molecular detection and identification of Leishmania infection in naturally infected sand flies in a focus of cutaneous leishmaniasis in northern Morocco

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Es-Sette, Nargys; Ajaoud, Malika; Laamrani-Idrissi, Abderrahman; Mellouki, Fouad; Lemrani, Meryem

2014-01-01

Background Cutaneous leishmaniasis is an infectious disease caused by various species of the flagellate protozoan Leishmania. During the past 20 years, cutaneous leishmaniasis has emerged as a major public health threat in Morocco. The main objective of this study was to study the occurrence of Leishmania infection in vectors and to identify sand fly blood meal sources in an endemic locality of cutaneous leishmaniasis within Sefrou province, where the vectors of leishmaniasis were still unkno...

Leishmania (Viannia) braziliensis infection in two Colombian dogs: a note on infectivity for sand flies and response to treatment.

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Travi, Bruno L; Tabares, Carlos Javier; Cadena, Horacio

2006-10-01

Although canine cutaneous leishmaniasis has been reported in several foci of South America, no published information from Colombia is available. We report on two cases found in the Pacific coast region of this country, which presented as a single scrotal ulcer in one dog, and two ulcers on the external surface of the ear in a second dog. Parasites were isolated by culture in Senekjie's culture medium and identified using monoclonal antibodies. The capacity of these dogs to transmit the parasites to sand fly vectors (Lutzomyia trapidoi, Lutzomyia gomezi, Lutzomyia longipalpis, Lutzomyia youngi) was tested by allowing the flies to feed on the lesion borders. Both isolates were identified as Leishmania (Viannia) braziliensis. No infections were detected upon dissection of engorged flies. A single peri-and sub-lesional injection of 1-2 ml of pentavalent antimony in the dog with ear lesions resulted in clinical cure 6 weeks post-treatment. These observations suggest that although dogs are susceptible to L. braziliensis, their reservoir competence could be low. However, if further studies indicate that canines are capable reservoir hosts of L. Viannia spp., the local treatment of lesions could become a feasible approach to diminish the risk of human infection in the peridomestic setting, without sacrificing infected dogs.

Dynamics of Haematobia irritans irritans (Diptera: Muscidae infestation on Nelore cattle in the Pantanal, Brazil

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Barros Antonio Thadeu M

2001-01-01

Full Text Available From June 1993 to May 1995, horn fly counts were conducted twice a month on untreated Nelore cattle raised extensively in the Pantanal. Horn fly population showed a bimodal fluctuation and peaks were observed every year after the beginning (November/December and at the end (May/June of the rainy season, which coincided with mid-late spring and mid-late fall, respectively. Horn flies were present on cattle throughout the year in at least 64% of the animals. Mean horn fly numbers on animals did not exceed 85 flies/cow during peaks and were under 35 flies/cow in most of the remaining periods. The highest infestations (population peaks were short and dropped suddenly within two weeks. Less than 15% of the animals in both herds could be considered as "fly-susceptible" - showing consistently higher infestations, or "fly-resistant" - showing consistently lower infestations.

Phlebotomine Sand Fly Fauna and Leishmania Infection in the Vicinity of the Serra do Cipó National Park, a Natural Brazilian Heritage Site

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Rosana Silva Lana

2015-01-01

Full Text Available In the New World, the leishmaniases are primarily transmitted to humans through the bites of Leishmania-infected Lutzomyia (Diptera: Psychodidae phlebotomine sand flies. Any or both of two basic clinical forms of these diseases are endemic to several cities in Brazil—the American cutaneous leishmaniasis (ACL and the American visceral leishmaniasis (AVL. The present study was conducted in the urban area of a small-sized Brazilian municipality (Jaboticatubas, in which three cases of AVL and nine of ACL have been reported in the last five years. Jaboticatubas is an important tourism hub, as it includes a major part of the Serra do Cipó National Park. Currently, no local data is available on the entomological fauna or circulating Leishmania. During the one-year period of this study, we captured 3,104 phlebotomine sand flies belonging to sixteen Lutzomyia species. In addition to identifying incriminated or suspected vectors of ACL with DNA of the etiological agent of AVL and vice versa, we also detected Leishmania DNA in unexpected Lutzomyia species. The expressive presence of vectors and natural Leishmania infection indicates favorable conditions for the spreading of leishmaniases in the vicinity of the Serra do Cipó National Park.

Mechanism of resistance to synthetic pyrethroids in buffalo flies in south-east Queensland

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Buffalo fly (Haematobia irritans exigua) and horn fly (Haematobia irritans irritans) cause irritation and production loss in much of the cattle producing area of the world. In Australia losses from buffalo fly were recently estimated at A$78m per year. Control is largely performed by using organoph...

Leishmania (Viannia braziliensis infection in two Colombian dogs: a note on infectivity for sand flies and response to treatment

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Bruno L. Travi

2006-10-01

Full Text Available Introduction. Although canine cutaneous leishmaniasis has been reported in several foci of South America, no published information from Colombia is available. Objective. We report on two cases found in the Pacific coast region of this country, which presented as a single scrotal ulcer in one dog, and two ulcers on the external surface of the ear in a second dog. Materials and methods. Parasites were isolated by culture in Senekjie’s culture medium and identified using monoclonal antibodies. The capacity of these dogs to transmit the parasites to sand fly vectors (Lutzomyia trapidoi, Lutzomyia gomezi, Lutzomyia longipalpis, Lutzomyia youngi was tested by allowing the flies to feed on the lesion borders. Results. Both isolates were identified as Leishmania (Viannia braziliensis. No infections were detected upon dissection of engorged flies. A single peri-and sub-lesional injection of 1-2 ml of pentavalent antimony in the dog with ear lesions resulted in clinical cure 6 weeks post-treatment. Conclusions. These observations suggest that although dogs are susceptible to L. braziliensis, their reservoir competence could be low. However, if further studies indicate that canines are capable reservoir hosts of L. Viannia spp., the local treatment of lesions could become a feasible approach to diminish the risk of human infection in the peridomestic setting, without sacrificing infected dogs.

Comparative Field Evaluation of Different Traps for Collecting Adult Phlebotomine Sand Flies (Diptera: Psychodidae) in an Endemic Area of Cutaneous Leishmaniasis in Quintana Roo, Mexico.

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Rodríguez-Rojas, Jorge J; Arque-Chunga, Wilfredo; Fernández-Salas, Ildefonso; Rebollar-Téllez, Eduardo A

2016-06-01

Phlebotominae are the vectors of Leishmania parasites. It is important to have available surveillance and collection methods for the sand fly vectors. The objectives of the present study were to evaluate and compare traps for the collection of sand fly species and to analyze trap catches along months and transects. Field evaluations over a year were conducted in an endemic area of leishmaniasis in the state of Quintana Roo, Mexico. A randomized-block design was implemented in study area with tropical rainforest vegetation. The study design utilized 4 transects with 11 trap types: 1) Centers for Disease Control and Prevention (CDC) light trap with incandescent bulb (CDC-I), 2) CDC light trap with blue light-emitting diodes (LEDs) (CDC-B), 3) CDC light trap with white LEDs (CDC-W), 4) CDC light trap with red LEDs (CDC-R), 5) CDC light trap with green LEDs (CDC-G), 6) Disney trap, 7) Disney trap with white LEDs, 8) sticky panels, 9) sticky panels with white LEDs, 10) delta-like trap, and 11) delta-like trap with white LEDs. A total of 1,014 specimens of 13 species and 2 genera (Lutzomyia and Brumptomyia) were collected. There were significant differences in the mean number of sand flies caught with the 11 traps; CDC-I was (P  =  0.0000) more effective than the other traps. Other traps exhibited the following results: CDC-W (17.46%), CDC-B (15.68%), CDC-G (14.89%), and CDC-R (14.30%). The relative abundance of different species varied according to trap types used, and the CDC-I trap attracted more specimens of the known vectors of Leishmania spp., such as like Lutzomyia cruciata, Lu. shannoni, and Lu. ovallesi. Disney trap captured more specimens of Lu. olmeca olmeca. Based on abundance and number of species, CDC light traps and Disney traps appeared to be good candidates for use in vector surveillance programs in this endemic area of Mexico.

Distribution of phlebotomine sand fly genotypes (Lutzomyia shannoni, Diptera: Psychodidae) across a highly heterogeneous landscape.

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Mukhopadhyay, J; Ghosh, K; Ferro, C; Munstermann, L E

2001-03-01

Genetic variability of eight Colombian field populations and two laboratory colonies of a tropical forest sand fly, Lutzomyia shannoni Dyar, was assessed by comparing allozyme frequencies at 20 enzyme loci. Substantial genetic variability was noted in all strains, with mean heterozygosities of 13-21% and alleles per locus of 2.0-2.8. Four loci were monomorphic. Six populations in north and central Colombia showed close genetic similarity (Nei's distances, 0.01-0.09), despite mountainous environment, discontinuous forest habitat, and elevation differences from 125 to 1,220 m. Two samples representing the Orinoco (near Villavicencio) and Amazon (near Leticia) river basins were similar (Nei's distance, 0.08) but diverged substantially from the central six samples (Nei's distances, 0.26-0.40). Although the range of L. shannoni extends from the southeastern United States to northern Argentina, three genetically distinct, geographically discrete, groups were discerned by the current analysis: Orinoco-Amazon river basins, north-central Colombia, and eastern United States.

Genetic structure and divergence in populations of Lutzomyia cruciata, a phlebotomine sand fly (Diptera: Psychodidae) vector of Leishmania mexicana in southeastern Mexico.

Science.gov (United States)

Pech-May, Angélica; Marina, Carlos F; Vázquez-Domínguez, Ella; Berzunza-Cruz, Miriam; Rebollar-Téllez, Eduardo A; Narváez-Zapata, José A; Moo-Llanes, David; Ibáñez-Bernal, Sergio; Ramsey, Janine M; Becker, Ingeborg

2013-06-01

The low dispersal capacity of sand flies could lead to population isolation due to geographic barriers, climate variation, or to population fragmentation associated with specific local habitats due to landscape modification. The phlebotomine sand fly Lutzomyia cruciata has a wide distribution throughout Mexico and is a vector of Leishmania mexicana in the southeast. The aim of this study was to evaluate the genetic diversity, structure, and divergence within and among populations of Lu. cruciata in the state of Chiapas, and to infer the intra-specific phylogeny using the 3' end of the mitochondrial cytochrome b gene. We analyzed 62 sequences from four Lu. cruciata populations and found 26 haplotypes, high genetic differentiation and restricted gene flow among populations (Fst=0.416, Nm=0.701, p<0.001). The highest diversity values were recorded in populations from Loma Bonita and Guadalupe Miramar. Three lineages (100% bootstrap and 7% overall divergence) were identified using a maximum likelihood phylogenetic analysis which showed high genetic divergence (17.2-22.7%). A minimum spanning haplotype network also supported separation into three lineages. Genetic structure and divergence within and among Lu. cruciata populations are hence affected by geographic heterogeneity and evolutionary background. Data obtained in the present study suggest that Lu. cruciata in the state of Chiapas consists of at least three lineages. Such findings may have implications for vector capacity and hence for vector control strategies. Copyright © 2013 Elsevier B.V. All rights reserved.

Vector competence of the stable fly (Diptera: Muscidae)for West Nile virus.

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Stable flies, which are notorious pests of cattle and other livestock, were suspected of transmitting West Nile virus (WNV) among American white pelicans at the Medicine Lake Wildlife Refuge in northeastern Montana in 2006-2007. However the ability of stable flies to transmit the virus was unknown. ...

Seasonality of sand flies (Diptera: Psychodidae) and Leishmania DNA detection in vector species in an area with endemic visceral leishmaniasis.

Science.gov (United States)

Saraiva, Lara; Leite, Camila Gonçalves; Lima, Ana Cristina Vianna Mariano da Rocha; Carvalho, Luiz Otávio Alves de; Pereira, Agnes Antônia Sampaio; Rugani, Jerônimo Marteleto Nunes; Rego, Felipe Dutra; Gontijo, Célia Maria Ferreira; Andrade, José Dilermando

2017-04-01

Leishmaniases are a serious health problem in southeast Brazil, including the city of Belo Horizonte (BH), Minas Gerais state (MG), where there are high rates of incidence and mortality due to visceral leishmaniases. BH is divided into nine sanitary districts (SD) of which one, the Venda Nova SD, was selected for this study because it has high rates of positivity for canine leishmaniasis and high incidence of human leishmaniasis. This study aimed to survey the sand fly fauna in Venda Nova SD from August 2011 to July 2013 and perform a descriptive analysis of the vector population. The sampling was carried out using automatic HP light traps at all covered areas of the Venda Nova SD, in a total of eighteen light traps. Sampled specimens were identified following Galati (2003), and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A simple environmental description was done for it area and Kernel estimation was used to infer vector density for each study site. A total of 2,427 sand fly specimens belonging to eight species and five genera were collected of which 95.3% were Lutzomyia longipalpis. The seasonal variation curve was delineated by this species. Lu. longipalpis was the most abundant at all collection points and in all months of the study, and exhibited a natural infection rate of 1.01% for Leishmania infantum and 1.77% for Leishmania braziliensis. The results show the presence and adaptation of Lu. longipalpis to the anthropic environment of BH and reinforces its role as the main vector of L. infantum in the region.

Seasonality of sand flies (Diptera: Psychodidae) and Leishmania DNA detection in vector species in an area with endemic visceral leishmaniasis

Science.gov (United States)

Saraiva, Lara; Leite, Camila Gonçalves; Lima, Ana Cristina Vianna Mariano da Rocha; de Carvalho, Luiz Otávio Alves; Pereira, Agnes Antônia Sampaio; Rugani, Jerônimo Marteleto Nunes; Rego, Felipe Dutra; Gontijo, Célia Maria Ferreira; Andrade, José Dilermando

2017-01-01

BACKGROUND Leishmaniases are a serious health problem in southeast Brazil, including the city of Belo Horizonte (BH), Minas Gerais state (MG), where there are high rates of incidence and mortality due to visceral leishmaniases. BH is divided into nine sanitary districts (SD) of which one, the Venda Nova SD, was selected for this study because it has high rates of positivity for canine leishmaniasis and high incidence of human leishmaniasis. OBJECTIVES This study aimed to survey the sand fly fauna in Venda Nova SD from August 2011 to July 2013 and perform a descriptive analysis of the vector population. METHODS The sampling was carried out using automatic HP light traps at all covered areas of the Venda Nova SD, in a total of eighteen light traps. Sampled specimens were identified following Galati (2003), and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A simple environmental description was done for it area and Kernel estimation was used to infer vector density for each study site. FINDINGS A total of 2,427 sand fly specimens belonging to eight species and five genera were collected of which 95.3% were Lutzomyia longipalpis. The seasonal variation curve was delineated by this species. Lu. longipalpis was the most abundant at all collection points and in all months of the study, and exhibited a natural infection rate of 1.01% for Leishmania infantum and 1.77% for Leishmania braziliensis. MAIN CONCLUSIONS The results show the presence and adaptation of Lu. longipalpis to the anthropic environment of BH and reinforces its role as the main vector of L. infantum in the region. PMID:28327794

The Phlebotominae sand fly (Diptera: Psychodidae fauna of two Atlantic Rain Forest Reserves in the State of Rio de Janeiro, Brazil

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Souza Nataly A

2001-01-01

Full Text Available During two consecutive years, studies on the sand fly fauna in Poço das Antas and Fazenda Bom Retiro, two Atlantic Rain Forest Reserves from the State of Rio de Janeiro, were performed using Shannon traps, CDC light traps and human bait collections. Eleven species were identified; Lutzomyia longipalpis, L. migonei, L. edwardsi, L. intermedia, L. whitmani, L. fischeri, L. shannoni, L. ayrozai, L. hirsuta, L. monticola and L. misionensis (first occurrence in the State of Rio de Janeiro. L. intermedia and L. whitmani were the predominant anthropophilic species around houses, while L. hirsuta predominated in the forest.

Discovery, Development, and Evaluation of a Horn Fly-Isolated (Diptera: Muscidae) Beauveria bassiana (Hypocreales: Cordyciptaceae) Strain From Florida, USA

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Holderman, Christopher J.; Wood, Lois A.; Geden, Christopher J.

2017-01-01

The horn fly, Haematobia irritans (L.) is an important cattle pest and traditionally has been managed using insecticides; however, many horn fly populations are insecticide-resistant in United States. Use of alternative control techniques has been limited because of the challenges of managing a fly pest on pastured cattle. After the discovery of a wild horn fly infected with Beauveria bassiana in Florida, the fungus was cultured and evaluated for efficacy against laboratory-reared horn flies. This fungal strain was selected for increased virulence by passage through laboratory-reared horn fly hosts to shorten interval from infection to fly death and subsequent conidia formation, properties important to future use of the fungus as a biological control agent against horn flies. After seven passages through horn fly hosts, fly mortality was not significantly accelerated as evaluated through LT50 values, but conidia were readily produced from these killed flies. Although further development is needed to improve fungal efficacy, this fungal strain holds promise as a biological control agent for inclusion in horn fly integrated pest management programs. PMID:28423414

Notes on the phlebotomine sand flies from the Peruvian southeast--I. Description of Lutzomyia (Helcocyrtomyia) adamsi n. sp. (Diptera: Psychodidae).

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Fernandez, R; Galati, E B; Carbajal, F; Wooster, M T; Watts, D M

1998-01-01

A new species of phlebotomine sand fly, Lutzomyia adamsi n. sp., is described and illustrated from specimens collected during August 1994, in Sandia, Department of Puno-Peru. According to the Oficina Nacional de Evaluacion de Recursos Naturales(ONERN 1976), this locality is situated in the life zone known as humid, mountain, low tropical forest (bh-MBT). Many areas in the northern part of Puno, mainly in the Inambari and Tambopata basins, are endemic to leishmaniasis. These areas are the continuation of others, largely known as "leishmaniasic" in the departments of Cusco and Madre de Dios. The morphological characteristics indicated that this species belongs to the genus Lutzomyia, subgenus Helcocyrtomyia Barretto, 1962.

Effects of pyriproxyfen and buprofezin on immature development, female oviposition, and egg-hatching in the stable fly

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The stable fly, Stomoxys calcitrans (L.) (Diptera: Muscidae), is one of the most economically significant biting flies affecting cattle. Use of traditional insecticides have only limited success in control of stable flies largely due to the stable fly’s unique feeding behaviors and immature developm...

Differential Haematobia irritans infestation levels in beef cattle raised in silvopastoral and conventional pasture systems.

Science.gov (United States)

de S Oliveira, Márcia Cristina; Nicodemo, Maria Luiza F; Gusmão, Marcos R; Pezzopane, José Ricardo M; Bilhassi, Talita B; Santana, Clarissa H; Gonçalves, Thuane C; Rabelo, Márcio D; Giglioti, Rodrigo

2017-11-15

The use of silvopastoral systems (SPS) can be a good alternative to reduce the environmental impacts of livestock breeding in Brazil. One of the reasons for its scarce adoption is the lack of information on health and productivity of cattle raised under these conditions. The experiment reported here was designed to compare the infestation by external parasites - the cattle tick (Rhipicephalus microplus), horn fly (Haematobia irritans), and larvae of the botfly (Dermatobia hominis) - in beef cattle raised in a SPS and a conventional pasture system (CPS), evaluated for 24 months. Data on air and soil temperature, solar radiation, wind incidence and water balance were used to characterize the SPS and CPS. R. microplus adult females and D. hominis larvae were counted on the body of each animal to determine the parasites burdens, but we did not find significant differences between the two systems. Horn flies counts on animals' body, and analysis of the horn fly and its pupal parasitoids associated with the dung pats were obtained in the two systems. Horn fly infestation was significantly lower (p=0.01) in the SPS (13.17±3.46) in comparison with the CPS (24.02±4.43). In SPS and CPS, respectively, the mean densities of pupae of H. irritansin dung pats were 9.8 and 10.7; the mean density of adults of H. irritans, 3.7 and 3.5; and the density of its pupal parasitoids were 20.5 and 5.4. The effect of production system was significant (p<0.05) only for the occurrence of pupal parasitoids of the horn fly, where the greatest occurrences of these natural enemies were in the SPS. These data indicate that natural enemies were able to control, at least partially, the horn fly populations in the cattle. Copyright © 2017 Elsevier B.V. All rights reserved.

Description of Lutzomyia velezi, a new species of phlebotomine sand fly (Diptera: Psychodidae) from the Department of Antioquia, Colombia.

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Bejarano, Eduar Elías; Vivero, Rafael José; Uribe, Sandra

2010-05-01

The phlebotomine sand fly Lutzomyia velezi sp.nov. was described and illustrated from male specimens collected by light trap in the Reserva Natural Cañon del Río Claro in the Central Cordillera of the Colombian Andes. The new species belongs to the series sanguinaria of the subgenus Helcocyrtomyia, which is represented in Colombia by Lutzomyia cirrita, Lutzomyia hartmanni, Lutzomyia sanguinaria, Lutzomyia scorzai, Lutzomyia sp. of Pichindé and Lutzomyia tortura. The new species can be differentiated from others of the subgenus by the combination of the following characteristics: long antennal ascoids, reaching level of the papilla, coxite with a single basal seta and fifth palpomere longer than or equal to the sum of the lengths of the third and fourth palpomeres.

Description of Lutzomyia velezi, a new species of phlebotomine sand fly (Diptera: Psychodidae from the Department of Antioquia, Colombia

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Eduar Elías Bejarano

2010-05-01

Full Text Available The phlebotomine sand fly Lutzomyia velezi sp.nov. was described and illustrated from male specimens collected by light trap in the Reserva Natural Cañon del Río Claro in the Central Cordillera of the Colombian Andes. The new species belongs to the series sanguinaria of the subgenus Helcocyrtomyia, which is represented in Colombia by Lutzomyia cirrita, Lutzomyia hartmanni, Lutzomyia sanguinaria, Lutzomyia scorzai, Lutzomyia sp. of Pichindé and Lutzomyia tortura. The new species can be differentiated from others of the subgenus by the combination of the following characteristics: long antennal ascoids, reaching level of the papilla, coxite with a single basal seta and fifth palpomere longer than or equal to the sum of the lengths of the third and fourth palpomeres.

Notes on the Phlebotomine Sand Flies from the Peruvian Southeast : I. Description of Lutzomyia (Helcocyrtomyia adamsi n. sp. (Diptera: Psychodidae

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Fernandez R

1998-01-01

Full Text Available A new species of phlebotomine sand fly, Lutzomyia adamsi n. sp., is described and illustrated from specimens collected during August 1994, in Sandia, Department of Puno-Peru. According to the Oficina Nacional de Evaluacion de Recursos Naturales(ONERN 1976, this locality is situated in the life zone known as humid, mountain, low tropical forest (bh-MBT. Many areas in the northern part of Puno, mainly in the Inambari and Tambopata basins, are endemic to leishmaniasis. These areas are the continuation of others, largely known as "leishmaniasic" in the departments of Cusco and Madre de Dios. The morphological characteristics indicated that this species belongs to the genus Lutzomyia, subgenus Helcocyrtomyia Barretto, 1962

Effect of fly ash content towards Sulphate resistance of oil palm shell lightweight aggregate concrete

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Muthusamy, K.; Fadzil, M. Y.; Nazrin Akmal, A. Z. Muhammad; Ahmad, S. Wan; Nur Azzimah, Z.; Hanafi, H. Mohd; Mohamad Hafizuddin, R.

2018-04-01

Both oil palm shell (OPS) and fly ash are by-product generated from the industries. Disposal of these by-product as wastes cause negative impact to the environment. The use of both oil palm shell and fly ash in concrete is seen as an economical solution for making green and denser concrete. The primary aim of this research is to determine the effects of FA utilization as sand replacement in oil palm shell lightweight aggregate concrete (OPS LWAC) towards sulphate resistance. Five concrete mixes containing fly ash as sand replacement namely 0%, 10%, 20%, 30% and 40% were prepared in these experimental work. All mixes were cast in form of cubes before subjected to sulphate solution for the period of 5 months. It was found that addition of 10% fly ash as sand replacement content resulted in better sulphate resistance of OPS LWAC. The occurrence of pozzolanic reaction due to the presence of FA in concrete has consumed the vulnerable Calcium hydroxide to be secondary C-S-H gel making the concrete denser and more durable.

Evaluation of surveillance methods for monitoring house fly abundance and activity on large commercial dairy operations.

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Gerry, Alec C; Higginbotham, G E; Periera, L N; Lam, A; Shelton, C R

2011-06-01

Relative house fly, Musca domestica L., activity at three large dairies in central California was monitored during the peak fly activity period from June to August 2005 by using spot cards, fly tapes, bait traps, and Alsynite traps. Counts for all monitoring methods were significantly related at two of three dairies; with spot card counts significantly related to fly tape counts recorded the same week, and both spot card counts and fly tape counts significantly related to bait trap counts 1-2 wk later. Mean fly counts differed significantly between dairies, but a significant interaction between dairies sampled and monitoring methods used demonstrates that between-dairy comparisons are unwise. Estimate precision was determined by the coefficient of variability (CV) (or SE/mean). Using a CV = 0.15 as a desired level of estimate precision and assuming an integrate pest management (IPM) action threshold near the peak house fly activity measured by each monitoring method, house fly monitoring at a large dairy would require 12 spot cards placed in midafternoon shaded fly resting sites near cattle or seven bait traps placed in open areas near cattle. Software (FlySpotter; http://ucanr.org/ sites/FlySpotter/download/) using computer vision technology was developed to count fly spots on a scanned image of a spot card to dramatically reduce time invested in monitoring house flies. Counts provided by the FlySpotter software were highly correlated to visual counts. The use of spot cards for monitoring house flies is recommended for dairy IPM programs.

Ecological Aspects of Phlebotomine Sand Flies (Diptera, Psychodidae, Phlebotominae) in Areas of American Cutaneous Leishmaniasis, in the Municipality of Paraty, Rio de Janeiro, Brazil. I-Index of Abundance by Location and Type of Capture.

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Vieira, V R; Azevedo, A C R; Alves, J R C; Guimarães, A E; Aguiar, G M

2015-09-01

The description of the first and autochthonous case of diffuse cutaneous leishmaniasis in the municipality of Paraty, State of Rio de Janeiro, brought the interest of this study. Sand flies were captured over a 3-yr period. Using manual suction tubes, sand flies were collected from the inner and outer walls of homes, in the living spaces of domestic animals, and in Shannon light traps, which were set up outside homes and in the forest. CDC light traps were installed inside homes, around the exterior of the houses, and along the divide and within the forest. A total of 102,937 sand flies were collected, representing 23 species--three from the genus Brumptomyia and 20 from the genus Lutzomyia. Of these, six species, Lutzomyia intermedia, Lutzomyia fischeri, Lutzomyia migonei, Lutzomyia whitmani, and Lutzomyia pessoai have already been recorded as being naturally infected by Leishmania braziliensis, and one species, Lutzomyia ayrozai, by Leishmania naiffi. Lu. intermedia is the vector of Le. braziliensis in the study area, particularly inside the homes and on the exterior of the houses. Lu. fischeri can also act as vector of Le. braziliensis in domestic environments and particularly in the wild. The third-ranked Lu. migonei was the most abundant in kennels, suggesting its canine affinity. Lu. whitmani, ranked fourth, still has characteristics indicative of the wild, but with a significant number located on the edge of the forest, suggesting a selection process of adaptation to the anthropic environment. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Dispersal pattern of the sand fly Lutzomyia neivai (Diptera: Psychodidae in a cutaneous leishmaniasis endemic rural area in Southeastern Brazil

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Cláudio Casanova

2005-11-01

Full Text Available The dispersal pattern of the sand fly Lutzomyia neivai was studied through mark-release-recapture experiments in an American cutaneous leishmaniasis endemic rural area in Southeastern Brazil. Over 6500 specimens were marked with fluorescent powder and released in forest edge and peridomicile habitats from August to November 1999, February and April 2000. Recapture attempts were made using Shannon and CDC traps up to eight successive nights after releases. A total of 493 (7.58% specimens were recaptured. The number of recaptured males and females of L. neivai in CDC traps was not affected by the distance between the trap and the release points. Approximately 90% of males and females recaptured in CDC traps were caught up to 70 m from the release points. The maximum female flight range recorded was 128 m. The average flight range per day was less than 60 m for males and females. Of the flies released in forest edge, approximately 16% of the recaptured females were caught in Shannon traps in the peridomicile habitat. The results indicate that the movements of L. neivai are spatially focal and the possibility of dispersion from forest to peridomicile habitat may be an important way of contracting leishmaniasis in dwellings.

Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

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Nirmala D.B.

2016-06-01

Full Text Available This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37 Orthogonal Arrays (OA with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering “Nominal the better” situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

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Nirmala, D. B.; Raviraj, S.

2016-06-01

This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering "Nominal the better" situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

Fauna de flebotomíneos (Diptera: Psychodidae em fragmentos de floresta ao redor de conjuntos habitacionais na cidade de Manaus, Amazonas, Brasil. I. Estratificação Vertical Sand flies fauna (Diptera: Psychodidae in forest fragments around housing complexes in the Manaus municipality, state of Amazonas, Brazil. I. Vertical Stratification

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Marlisson Augusto Costa Feitosa

2006-12-01

Full Text Available No período de janeiro a agosto de 1999 foram realizadas coletas de flebotomíneos (Diptera: Psychodidae em duas áreas de floresta residual (Estrada do Turismo e Cidade de Deus, na periferia da cidade de Manaus (AM, tendo o objetivo de verificar as espécies e a estratificação vertical. Foram utilizadas armadilhas luminosas tipo CDC, colocadas nos fragmentos de florestas a um e dez metros de altura. Foram capturados 7.516 flebotomíneos distribuídos em 45 espécies; 4.836 espécimes, de 36 espécies, na estrada de Turismo e 2.680 exemplares, de 40 espécies, na Cidade de Deus. Predominaram na Estrada do Turismo Lutzomyia umbratilis e L. ubiquitalis e na Cidade de Deus, L. umbratilis e L. anduzei. A presença de algumas espécies, apenas em certas áreas, indica a adaptabilidade destes flebotomíneos em áreas sobre ação antrópica.Between January and August of 1999, a study was carried out on the phlebotomine (Diptera: Psychodidae sand flies occurrence in two areas of residual forest (Estrada do Turismo and Cidade de Deus, in the periphery of Manaus, AM. The objective of this study was to verify the Phlebotominae sand fly fauna and vertical stratification. CDC light traps were placed in the forests, one to ten meters in height. A total of 7.516 sand flies, distributed in 45 species, were captured: 4.836 specimens of 36 species in the Estrada do Turismo and 2.680 individuals of 40 species in the Cidade de Deus.Predominant in the Estrada do Turismo were the species Lutzomyia umbratilis and L. ubiquitalis were as L. umbratilis and L. anduzei prevailed in the Cidade de Deus. Different Phlebotominae sand fly species in certain areas, showed an adaptation of these sand flies to areas of human activity.

Comparison of the olfactory preferences of four species of filth fly pupal parasitoid species (Hymenoptera: Pteromalidae) for hosts in equine and bovine manure

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House flies (Musca domestica L.) and stable flies (Stomoxys calcitrans (L.)) (Diptera: Muscidae) are common pests in equine and cattle facilities. Pupal parasitoids primarily in the genera Spalangia and Muscidifurax (Hymenoptera: Pteromalidae) can be purchased for biological control of these flies. ...

Seroprevalence and risk factors of Besnoitia besnoiti infection in Korean cattle - short communication.

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Lee, Seung-Hun; Eo, Kyung-Yeon; Jung, Byeong Yeal; Kwak, Dongmi; Kwon, Oh-Deog

2017-12-01

Besnoitia besnoiti is an obligate intracellular parasite that is transmitted by direct contact or via mechanical transmission by flies as vectors. Besnoitiosis causes economic losses in the cattle industry and is regarded as a re-emerging disease in Europe. This study evaluated the seroprevalence of B. besnoiti in Korean cattle using a commercial ELISA kit. Among 558 serum samples, 19 (3.4%) tested seropositive for B. besnoiti. The statistically significant risk factors included age (≥ 2 years), sex (castrated males), and region (lower latitudes) (P cattle reared in Korea. Thus, the practice of intensive cattle husbandry and the regionally different seroprevalence of B. besnoiti infection in cattle in Korea warrant routine monitoring and vector control to reduce economical losses due to bovine besnoitiosis in the country.

Performance evaluation of clay fly ash brick masonry

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Kute, S.; Deodhar, S.V. [K.K. Wagh College of Engineering, Panchavati (India). Dept. of Civil Engineering

2003-07-01

Despite inexorable trends of automation in manufacturing industry throughout the world, the conventional brick manufacturing practices have remained largely unchanged since the dawn of civilization in India. This has imposed restrictions on quality of bricks in general. The paper highlights the results derived from an extensive experimental work on performance evaluation of brick masonry. Four types of bricks, three values of joint thickness and fineness modulus of sand, and two grades of mortar with four different proportions were used as samples. Fly ash was from Nashik Thermal Power Station in Maharashtra, India. The results show that the brick masonry of 40% fly ash bricks and mortar with 20% fly ash as replacement to cement with 1:4 and 1:6 proportion gives optimum strength and advocates use of fly ash for this combination. 8 tabs.

Morphometric and molecular analyses of the sand fly species Lutzomyia shannoni (Diptera: Psychodidae: Phlebotominae) collected from seven different geographical areas in the southeastern United States.

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Florin, David A; Davies, Stephen J; Olsen, Cara; Lawyer, Phillip; Lipnick, Robert; Schultz, George; Rowton, Edgar; Wilkerson, Richard; Keep, Lisa

2011-03-01

A morphometric and molecular study of adult male and female Lutzomyia shannoni (Dyar 1929) collected at seven different locations within the southeastern United States was conducted to assess the degree of divergence between the grouped specimens from each location. The collection locations were as follows: Fort Bragg, NC; Fort Campbell, KY; Fort Rucker, AL; Ossabaw Island, GA; Patuxent National Wildlife Research Refuge, MD; Suwannee National Wildlife Refuge, FL; and Baton Rouge, LA. Forty males and forty females from each location were analyzed morphometrically from 54 and 49 character measurements, respectively. In addition, the molecular markers consisting of the partial cytochrome c oxidase subunit I (from 105 sand flies: 15 specimens/collection site) and the partial internal transcribed spacer 2 (from 42 sand flies: six specimens/collection site) were compared. Multivariate analyses indicate that the low degree of variation between the grouped specimens from each collection site prevents the separation of any collection site into an entity that could be interpreted as a distinct population. The molecular analyses were in concordance with the morphometric study as no collection location grouped into a separate population based on the two partial markers. The grouped specimens from each collection site appear to be within the normal variance of the species, indicating a single population in the southeast United States. It is recommended that additional character analyses of L. shannoni based on more molecular markers, behavioral, ecological, and physiological characteristics, be conducted before ruling out the possibility of populations or a cryptic species complex within the southeastern United States.

Larval microhabitats of Lutzomyia longipalpis (Diptera: Psychodidae) in an endemic focus of visceral leishmaniasis in Colombia.

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Ferro, C; Pardo, R; Torres, M; Morrison, A C

1997-11-01

An intensive search for the larval habitats of Lutzomyia longipalpis (Lutz & Neiva) was conducted from November 1992 to October 1993 at a small rural community in Colombia where American visceral leishmaniasis is endemic. Emergence traps constructed from polyvinyl chloride pipes were used to sample a variety of soil microhabitats that included edge areas of covered pigpens, cattle corrals, the base of trees, and leaf litter at sites within 40 m of a house, rocks in fields located between 50 and 500 m from houses, and sites within a patch of secondary forest (rocks, base of palm trees, and leaf litter). The teneral status of the sand flies captured in the emergence traps was confirmed by laboratory studies that determined the rate of terminalia rotation in male L. longipalpis and the rate of cuticular growth layer formation of the thoracic phragma in both sexes of this species. A total of 58 teneral sand flies was captured during the study period (49 wk). Fifteen specimens were L. longipalpis; of these 11 (5 sand flies per square meter) were captured near pigpens, 3 (1.4 sand flies per square meter) were captured near rock resting sites, and 1 (1.6 sand flies per square meter) was collected at the base of a tree. The remainder of the sand flies were either L. trinidadensis (Newstead) or L. cayennensis (Flock & Abonnenc). Our results indicate that L. longipalpis larvae were dispersed widely in sites near houses, rather than concentrated in a few optimal microhabitats.

Cs and Cl penetration estimation in mortar from fly ash of MSWI

International Nuclear Information System (INIS)

Yamada, K.; Hosokawa, Y.; Haga, K.; Osako, M.

2015-01-01

By the Fukushima Daiichi accident, radioactive Cs was scattered widely in East Japan. From the viewpoint of radionuclide contaminated wastes management, water soluble Cs in the fly ash of incineration of municipal solid wastes (MSWI-FA) is the most serious problem. When final disposal of MSWI-FA contaminated by radioactive Cs in concrete pit is considered, it is necessary to understand the characteristics of MSWI-FA and Cs penetration behavior into concrete. In this study, the expected solution generated from MSWI-FA is analyzed and immersion test of mortar in this model solution was carried out for several kinds of cement and sand types. Cs showed similar penetration profiles with Cl regardless of cement and sand types. By using fly ash cement, the penetration depth of Cs decreased less than half compared to ordinary Portland cement (OPC). Clay mineral in sand did not affect the penetration of Cs possible because of the competing effect of potassium for Cs adsorption. Assuming a diffusion equation considering non-linear binding, from the measured profiles, diffusion coefficient and parameters of binding were obtained by fitting. Then, the Cs and Cl profiles after 30 years are estimated and penetration depths of Cs and Cl were only 15 mm for fly ash mortar. (authors)

Pervious concrete using fly ash aggregate as coarse aggregate-an experimental study

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Dash, Subhakanta; Kar, Biswabandita; Mukherjee, Partha Sarathi

2018-05-01

The present study deals with the fabrication of pervious concrete from fly ash aggregates. The pervious concrete were obtained by the mixture of three different size fly ash aggregates (4.75 mm,9.5 mm,12.5 mm), Portland cement, water with little amount of sand or without sand. Admixtures like Silica fume(SF) and Super plasticizer are added to the mixture to enhance the strength of concrete. Trial being taken on preparation of Fly ash based pervious concrete (FPC) with different w/c ratio i.e. 0.30, 0.35 and 0.40 respectively. Tests such as porosity, permeability and compressive, strength are studied for this concrete material and the result concluded that the concrete when cured for 28 days its compressive strength falls in between 7.15 - 15.74 MPa and permeability 9.38 - 16.07 mm/s with porosity 27.59 - 34.05% and these are suited to be used as for use as an environment friendly concrete.

Elastic properties of fly ash-stabilized mixes

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Sanja Dimter

2015-12-01

Full Text Available Stabilized mixes are used in the construction of bearing layers in asphalt and concrete pavement structures. Two nondestructive methods: resonant frequency method and ultrasonic pulse velocity method, were used for estimation of elastic properties of fly ash–stabilized mixes. Stabilized mixes were designed containing sand from the river Drava and binder composed of different share of cement and fly ash. The aim of the research was to analyze the relationship between the dynamic modulus of elasticity determined by different nondestructive methods. Data showed that average value of elasticity modulus obtained by the ultrasound velocity method is lower than the values of elasticity modulus obtained by resonant frequency method. For further analysis and enhanced discussion of elastic properties of fly ash stabilized mixes, see Dimter et al. [1].

Efeito da mosca-dos-chifres, Haematobia irritans (L. (Diptera: Muscidae, no ganho de peso de bovinos Nelore Effects of the horn fly, Haematobia irritans (L. (Diptera: Muscidae in the weight gain on Nellore cattle

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Ivo Bianchin

2004-06-01

Full Text Available A presente investigação foi realizada devido à escassez, no Brasil, de informações sobre os possíveis danos decorrentes da ação hematófaga da mosca-dos-chifres, Haematobia irritans (L., em bovinos da raça Nelore. O estudo foi realizado durante quatro estações chuvosas (outubro a abril, de 1991 a 1995. Em cada ano, 80 bovinos foram utilizados de acordo com os seguintes tratamentos: 28 touros com um ano de idade divididos em quatro grupos; 20 bois com idade de dois anos divididos em quatro grupos, e 32 bois com três anos e divididos em oito grupos. Metade dos grupos de animais de cada idade eram tratados contra H. irritans com intervalos de 28 dias e os demais mantidos como grupos controle. As moscas foram contadas a cada 14 dias e o peso dos bois registrado a cada 28. O número médio de mosca/animal dos grupos controle para o primeiro, segundo, terceiro e quarto anos do estudo foi, respectivamente: cinco, cinco, quatro e cinco, nos animais de um ano; 15, 11, 13 e 27, nos de dois anos e 55, 31, 40 e 51, nos de três anos. Observou-se que maior número de moscas (PThis investigation was carried out due the lack of information about the possible effects of the blood-feeding horn fly, Haematobia irritans (L., on Nellore cattle. Data were recorded during four rainy seasons (October to April from 1991 to 1995. In each year, 80 animals were utilized according to the following treatments: twenty-eight 1-year old bulls divided into four groups; twenty 2-year old cattle divided into four groups and thirty-two 3-year old cattle divided into eight groups. Treatments against H. irritans were conduced at about 28-day intervals on half part of each age groups and the remainders groups maintained without treatment as control. The flies were counted at 14-day intervals and the animals weight registered at each 28-day intervals. The values for the mean flies number on the animals of the control groups in the first, second, third and fourth years of

External radiation doses from deposed fly ash with a content of 40K, 226Ra and 232Th

International Nuclear Information System (INIS)

Hedemann Jensen, P.

1991-12-01

Fly ash from coal fired power plants might be used as filling material below buildings used for habitation. The fly ash content of the radionuclides of potassium, thorium and radium can cause external exposure of the inhabitants to γ radiation emitted during the radioactive decay of those radionuclides. Methods for calculation of the γ dose rate in air at indoor and outdoor positions are described. The dependence of the air dose rate on the vertical and horizontal dimensions of the fly ash material and on the thickness of a covering layer of soil or sand is analysed. The effective annual dose to inhabitants are calculated for typical Danish housing conditions with the buildings placed on a layer of fly ash of infinite vertical and horizontal dimensions and covered by soil or sand of varying thickness. (au) 10 refs

Pemanfaatan limbah abu terbang (fly ash) , abu dasar (bottom ash) batubara dan limbah padat (sludge) industri karet sebagai bahan campuran pada pembuatan batako

OpenAIRE

Faisal, Hendri

2012-01-01

Brick-making research has been conducted from a mixture of fly ash as a cement mixed with aggregate materials based bottom ash and sludge, and sand, where fly ash and cement used as an adhesive matrix. The percentage addition of fly ash is 10%, 20%, 30%, 40% and 50% of initial weight of cement. The percentage addition of bottom ash and sludge as an aggregate is 5%, 10%, 15%, 20% and 25% of initial weight of sand with the time of hardening for 28 days. Parameter tests performed include: metals...

A Naturally Occurring Deletion in FliE from Salmonella enterica Serovar Dublin Results in an Aflagellate Phenotype and Defective Proinflammatory Properties.

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Sasías, Sebastián; Martínez-Sanguiné, Adriana; Betancor, Laura; Martínez, Arací; D'Alessandro, Bruno; Iriarte, Andrés; Chabalgoity, José A; Yim, Lucía

2018-01-01

Salmonella enterica serovar Dublin is adapted to cattle but is able to infect humans with high invasiveness. An acute inflammatory response at the intestine helps to prevent Salmonella dissemination to systemic sites. Flagella contribute to this response by providing motility and FliC-mediated signaling through pattern recognition receptors. In a previous work, we reported a high frequency (11 out of 25) of S Dublin isolates lacking flagella in a collection obtained from humans and cattle. The aflagellate strains were impaired in their proinflammatory properties in vitro and in vivo The aim of this work was to elucidate the underlying cause of the absence of flagella in S Dublin isolates. We report here that class 3 flagellar genes are repressed in the human aflagellate isolates, due to impaired secretion of FliA anti-sigma factor FlgM. This phenotype is due to an in-frame 42-nucleotide deletion in the fliE gene, which codes for a protein located in the flagellar basal body. The deletion is predicted to produce a protein lacking amino acids 18 to 31. The aflagellate phenotype was highly stable; revertants were obtained only when fliA was artificially overexpressed combined with several successive passages in motility agar. DNA sequence analysis revealed that motile revertants resulted from duplications of DNA sequences in fliE adjacent to the deleted region. These duplications produced a FliE protein of similar length to the wild type and demonstrate that amino acids 18 to 31 of FliE are not essential. The same deletion was detected in S Dublin isolates obtained from cattle, indicating that this mutation circulates in nature. Copyright © 2017 American Society for Microbiology.

Biofuel Combustion Fly Ash Influence on the Properties of Concrete

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Aurelijus Daugėla

2016-02-01

Full Text Available Cement as the binding agent in the production of concrete can be replaced with active mineral admixtures. Biofuel combustion fly ash is one of such admixtures. Materials used for the study: Portland cement CEM I 42.5 R, sand of 0/4 fraction, gravel of 4/16 fraction, biofuel fly ash, superplasticizer, water. Six compositions of concrete were designed by replacing 0%, 5%, 10%, 15% 20%, and 25% of cement with biofuel fly ash. The article analyses the effect of biofuel fly ash content on the properties of concrete. The tests revealed that the increase of biofuel fly ash content up to 20% increases concrete density and compressive strength after 7 and 28 days of curing and decreases water absorption, with corrected water content by using plasticizing admixture. It was found that concrete where 20% of cement is replaced by biofuel ash has higher frost resistance.

Leishmania infantum proteophosphoglycans regurgitated by the bite of its natural sand fly vector, Lutzomyia longipalpis, promote parasite establishment in mouse skin and skin-distant tissues.

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Rogers, Matthew Edward; Corware, Karina; Müller, Ingrid; Bates, Paul Andrew

2010-10-01

We demonstrate that a proteophosphoglycan-rich gel secreted by Leishmania infantum inside the midgut of Lutzomyia longipalpis sand flies (promastigote secretory gel) is regurgitated along with an average dose of 500 L. infantum metacyclic promastigotes per infected bite. Using both low (10³) and high (10⁵) doses of parasites in the ears of BALB/c mice we show that the infections benefit from the presence of vector saliva and parasite gel in the skin. However, chronic infection of the spleen was only enhanced in high dose co-infections with gel. These results provide the framework for a more natural experimental model of visceral leishmaniasis. Copyright © 2010. Published by Elsevier SAS.

External morphology of sensory structures of fourth instar larvae of neotropical species of phlebotomine sand flies (Diptera: Psychodidae under scanning electron microscopy

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Pessoa Felipe Arley Costa

2001-01-01

Full Text Available In the present study, some morphological structures of antennae, maxillary palps and caudal setae of fourth instar larvae of laboratory-reared phlebotomine sand flies (Lutzomyia longipalpis, L. migonei, L. evandroi, L. lenti, L. sericea, L. whitmani and L. intermedia of the State of Ceará, Brazil, were examined under scanning electron microscopy. The antennal structures exhibited considerable variation in the morphology and position. A prominent digitiform distal segment has been observed only on the antenna of species of the subgenus Nyssomyia. The taxonomic relevance of this and other antennal structure is discussed. The papiliform structures found in the maxillae and the porous structures of the caudal setae of all species examined may have chemosensory function. Further studies with transmission electron microscopy are needed to better understand the physiological function of these external structures.

[Occurrence of sand flies (Diptera, Psychodidae) in leishmaniasis foci in an ecotourism area around the Lençóis Maranhenses National Park, Brazil].

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Rebêlo, José Manuel Macário; Assunção Júnior, Antonildes Nascimento; Silva, Orleans; Moraes, Jorge Luiz Pinto

2010-01-01

The distribution and relative abundance of sand fly species were studied in the municipality of Barreirinhas, Maranhão State, Brazil, around the Lençóis Maranhenses National Park, from January to June 2005, August 2004, July 2005, and September/2008. A total of 6,658 specimens were captured. The most frequent species were Lutzomyia whitmani (46.6%), L. longipalpis (29.9%), L. evandroi (17.1%), and L. lenti (4.8%), while L. termitophila, L. flaviscutellata, L. migonei, L. infraspinosa, L. sordellii, L. wellcomei, L. antunesi, and L. trinidadensis represented 1.6%. The presence of Leishmania vector species explains the high detection rate for tegumentary leishmaniasis in 2000 (308.2), 2001 (310.9), 2002 (338.2), and 2005 (313.6) and active foci of human visceral leishmaniasis in the municipality of Barreirinhas.

Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash

Science.gov (United States)

Yoshitake, Isamu; Ishida, Takeo; Fukumoto, Sunao

2015-01-01

Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability. PMID:28793518

Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash.

Science.gov (United States)

Yoshitake, Isamu; Ishida, Takeo; Fukumoto, Sunao

2015-08-21

Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability.

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

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

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

Tsetse flies and their control.

Science.gov (United States)

Rogers, D J; Hendrickx, G; Slingenbergh, J H

1994-12-01

The authors use a quantitative modelling framework to describe and explore the features of the biology of tsetse flies (Glossina spp.) which are important in determining the rate of transmission of the African trypanosomiases between hosts. Examples are presented of the contribution of previous research on tsetse to quantified epidemiological and epizootiological understanding, and areas of current ignorance are identified for future study. Spatial and temporal variations in risk are important (but rarely-studied) determinants of the impact of trypanosomiasis on humans, domestic animals and agricultural activities. Recent grid-based sampling surveys to Togo provide valuable data sets on tsetse, cattle and trypanosomiasis throughout the country. A combination of ground-based meterological and remotely-sensed satellite data, within linear discriminant analytical models, enables description of the observed distributions of the five species of tsetse occurring in Togo, with accuracies of between 72% (Glossina palpalis and G. tachinoides) and 98% (G. fusca). Abundance classes of the two most widespread species, G. palpalis and G. tachinoides, are described with accuracies of between 47% and 83%. This is especially remarkable given the relatively small differences between the average values of the predictor variables in areas of differing fly abundance. Similar analyses could be used to predict the occurrence and abundance of flies in other areas, which have not been surveyed to date, in order to plan tsetse control campaigns or explore development options. Finally, some recent tsetse control campaigns are briefly reviewed. The shift of emphasis from fly eradication to fly control is associated with a devolution of responsibility for control activities from central government to local areas, communities or even individuals. The future role of central governments will remain crucial, however, in determining the areas in which different control options are practised, in

Repellent effectiveness of seven plant essential oils, sunflower oil and natural insecticides against horn flies on pastured dairy cows and heifers.

Science.gov (United States)

Lachance, S; Grange, G

2014-06-01

Plant essential oils (basil, geranium, balsam fir, lavender, lemongrass, peppermint, pine and tea tree), mixed with either sunflower oil or ethyl alcohol, were applied at 5% concentrations to the sides of Holstein cattle. Pastured cattle treated with essential oils diluted in sunflower oil had less flies than the untreated control for a 24-h period. However, the essential oil treatments were not significantly different than the carrier oil alone. Barn-held heifers treated with essential oils and sunflower oil alone had significantly less flies than the untreated control for up to 8 h after treatment. Basil, geranium, lavender, lemongrass and peppermint repelled more flies than sunflower oil alone for a period ranging from 1.5 to 4 h after treatments applied to heifers. All essential oils repelled > 75% of the flies on the treated area for 6 and 8 h on pastured cows and indoor heifers, respectively. Geranium, lemongrass and peppermint stayed effective for a longer duration. Essential oils mixed with ethyl alcohol demonstrated less repellence than when mixed with the carrier oil. Safer's soap, natural pyrethrins without piperonyl butoxide and ethyl alcohol alone were not efficient at repelling flies. Essential oils could be formulated for use as fly repellents in livestock production. © 2013 The Royal Entomological Society.

American Cutaneous Leishmaniasis in Panama: a historical review of entomological studies on anthropophilic Lutzomyia sand fly species

Science.gov (United States)

2014-01-01

We review existing information on the epidemiology of American Cutaneous Leishmaniasis (ACL) in Panama, with emphasis on the bionomics of anthropophilic Lutzomyia sand fly species. Evidence from Panamanian studies suggests that there are six anthropophilic species in the country: Lutzomyia trapidoi, Lu. panamensis, Lu. gomezi, Lu. ylephiletor, Lu. sanguinaria and Lu. pessoana (Henceforth Lu. carrerai thula). In general, these taxa are abundant, widespread and feed opportunistically on their hosts, which make them potential transmitters of pathogens to a broad range of wildlife, domesticated animals and humans. Furthermore, nearly all man-biting species in Panama (with the exception of Lu. gomezi) expand demographically during the rainy season when transmission is likely higher due to elevated Leishmania infection rates in vector populations. Despite this, data on the distribution and prevalence of ACL suggest little influence of vector density on transmission intensity. Apart from Lu. trapidoi, anthropophilic species seem to be most active in the understory, but vertical stratification, as well as their opportunistic feeding behavior, could vary geographically. This in turn seems related to variation in host species composition and relative abundance across sites that have experienced different degrees of human alteration (e.g., deforestation) in leishmaniasis endemic regions of Panama. PMID:24886629

Population dynamics of stable flies Stomoxys calcitrans (Diptera: Muscidae) at an organic dairy farm in Denmark based on mark-recapture with destructive sub-sampling

DEFF Research Database (Denmark)

Pedersen, Henrik Skovgård; Nachman, Gøsta Støger

2012-01-01

A population of stable flies, Stomoxys calcitrans (L.), was studied on a Danish cattle farm in two successive years. Flies were captured monthly by sweep nettings and marked with fluorescent dust. Absolute population size, dilution rate, loss rate, and adult longevity were estimated by means...

The uniform design experimental research of a large amount of fly ash self-compaction concrete

Energy Technology Data Exchange (ETDEWEB)

Zhou, M.; Ji, C.; Xiao, J. [Liaoning Technical University, Fuxin (China)

2005-08-15

The paper studied the effect of quantity of cementing material and fly ash, W/B (water-binder) ratio, admixture and sand percentage to the performance of super fly-ash self-compaction concrete. It also utilized the step-by-step regression analysis method in SPSS software to found regression equation, which uses the flow rate of concrete mixture and strength of concrete as objective function, and obtained the optimum mix proportion of super fly ash self-compaction by the optimization technology in the Matlab software.

Courtship behaviour of Phlebotomus papatasi the sand fly vector of cutaneous leishmaniasis

Directory of Open Access Journals (Sweden)

Chelbi Ifhem

2012-08-01

Full Text Available Abstract Background The sand fly Phlebotomus papatasi is an Old World vector of Leishmania major, the etiologic agent of zoonotic cutaneous leishmaniasis. This study describes the courtship behaviour of P. papatasi and compares it with that of Lutzomyia longipalpis, the New World vector of visceral leishmaniasis. Understanding the details of courtship behaviour in P. papatasi may help us to understand the role of sex pheromones in this important vector. Results P. papatasi courtship was found to start with the female touching the male, leading him to begin abdomen bending and wing flapping. Following a period of leg rubbing and facing, the male flaps his wings while approaching the female. The female then briefly flaps her wings in response, to indicate that she is willing to mate, thereby signaling the male to begin copulation. Male P. papatasi did not engage in parading behaviour, which is performed by male L. longipalpis to mark out individual territories during lekking (the establishment and maintenance of mating aggregations, or wing-flap during copulation, believed to function in the production of audio signals important to mate recognition. In P. papatasi the only predictor of mating success for males was previous copulation attempts and for females stationary wing-flapping. By contrast, male L. longipalpis mating success is predicted by male approach-flapping and semi-circling behaviour and for females stationary wing-flapping. Conclusions The results show that there are important differences between the mating behaviours of P. papatasi and L. longipalpis. Abdomen bending, which does not occur in L. longipalpis, may act in the release of sex pheromone from an as yet unidentified site in the male abdomen. In male L. longipalpis wing-flapping is believed to be associated with distribution of male pheromone. These different behaviours are likely to signify significant differences in how pheromone is used, an observation that is consistent

Control of Phlebotomus argentipes (Diptera: Psychodidae sand fly in Bangladesh: A cluster randomized controlled trial.

Directory of Open Access Journals (Sweden)

Rajib Chowdhury

2017-09-01

Full Text Available A number of studies on visceral leishmaniasis (VL vector control have been conducted during the past decade, sometimes came to very different conclusion. The present study on a large sample investigated different options which are partially unexplored including: (1 indoor residual spraying (IRS with alpha cypermethrin 5WP; (2 long lasting insecticide impregnated bed-net (LLIN; (3 impregnation of local bed-nets with slow release insecticide K-O TAB 1-2-3 (KOTAB; (4 insecticide spraying in potential breeding sites outside of house using chlorpyrifos 20EC (OUT and different combinations of the above.The study was a cluster randomized controlled trial where 3089 houses from 11 villages were divided into 10 sections, each section with 6 clusters and each cluster having approximately 50 houses. Based on vector density (males plus females during baseline survey, the 60 clusters were categorized into 3 groups: (1 high, (2 medium and (3 low. Each group had 20 clusters. From these three groups, 6 clusters (about 300 households were randomly selected for each type of intervention and control arms. Vector density was measured before and 2, 4, 5, 7, 11, 14, 15, 18 and 22 months after intervention using CDC light traps. The impact of interventions was measured by using the difference-in-differences regression model.A total of 17,434 sand flies were collected at baseline and during the surveys conducted over 9 months following the baseline measurements. At baseline, the average P. argentipes density per household was 10.6 (SD = 11.5 in the control arm and 7.3 (SD = 8.46 to 11.5 (SD = 20.2 in intervention arms. The intervention results presented as the range of percent reductions of sand flies (males plus females and rate ratios in 9 measurements over 22 months. Among single type interventions, the effect of IRS with 2 rounds of spraying (applied by the research team ranged from 13% to 75% reduction of P. argentipes density compared to the control arm (rate

Pengaruh Penambahan Limbah Padat Abu Terbang Batubara(fly Ash) Terhadap Kekuatan Tekan Dan Porositas Genteng Tanah Liat Kabupaten Pringsewu

OpenAIRE

Febriyansyah, Puji; Tarkono,; Zulhanif,

2013-01-01

Fly ash, chemicallyis analumino-silicamineral containing Ca, K, and Na elements, fly ash has amoderate to high bonding capacity characteristic , and has acement-forming properties. In this study the authors use the industrial fly ash coal waste as an alternative mixture of tile manufacture. The tiles manufactured by mixing clay, sand, water and fly ash. Then smoothed with ekstuder machine and forming kuweh then aerate for 3 days, before do the dieing process . Tile dried for 4 days, then do f...

Nutrient concentrations in leachate and runoff from dairy cattle lots with different surface materials

Science.gov (United States)

Nitrogen (N) and phosphorus (P) loss from agriculture persists as a water quality issue, and outdoor cattle lots can have a high loss potential. We monitored hydrology and nutrient concentrations in leachate and runoff from dairy heifer lots constructed with three surface materials (soil, sand, bark...

Experimental investigation on depression mechanism of fly ash on progression of leaching alteration front

International Nuclear Information System (INIS)

Yamamoto, Takeshi; Hironaga, Michihiko

2008-01-01

An objective of this experimental study is to clarify the depression mechanism of fly ash on leaching alteration in hardened cementitious material. There are two major effects that derived from fly ash, firstly, compacting capillary pore among hydration phase with progression of pozzolanic reaction, secondly, lessen the crystal size and dispersing the location of CH crystal. Progression rate of CH alteration front depends on chain dissolution of CH crystal, so the depression on progressing rate of CH alteration front would be derived from the effects of fly ash as mentioned above. The influences of difference in amount of mixing water and sand on progression rate of CH alteration front in mortar would also be depressed by mixing fly ash. (author)

CATTLE FEEDER BEHAVIOR AND FEEDER CATTLE PLACEMENTS

OpenAIRE

Kastens, Terry L.; Schroeder, Ted C.

1994-01-01

Cattle feeders appear irrational when they place cattle on feed when projected profit is negative. Long futures positions appear to offer superior returns to cattle feeding investment. Cattle feeder behavior suggests that they believe a downward bias in live cattle futures persists and that cattle feeders use different expectations than the live cattle futures market price when making placement decisions. This study examines feeder cattle placement determinants, comparing performance of expec...

The maximum percentage of fly ash to replace part of original Portland cement (OPC) in producing high strength concrete

Science.gov (United States)

Mallisa, Harun; Turuallo, Gidion

2017-11-01

This research investigates the maximum percent of fly ash to replace part of Orginal Portland Cement (OPC) in producing high strength concrete. Many researchers have found that the incorporation of industrial by-products such as fly ash as in producing concrete can improve properties in both fresh and hardened state of concrete. The water-binder ratio was used 0.30. The used sand was medium sand with the maximum size of coarse aggregate was 20 mm. The cement was Type I, which was Bosowa Cement produced by PT Bosowa. The percentages of fly ash to the total of a binder, which were used in this research, were 0, 10, 15, 20, 25 and 30%; while the super platicizer used was typed Naptha 511P. The results showed that the replacement cement up to 25 % of the total weight of binder resulted compressive strength higher than the minimum strength at one day of high-strength concrete.

Repeated exposure to Lutzomyia intermedia sand fly saliva induces local expression of interferon-inducible genes both at the site of injection in mice and in human blood.

Science.gov (United States)

Weinkopff, Tiffany; de Oliveira, Camila I; de Carvalho, Augusto M; Hauyon-La Torre, Yazmin; Muniz, Aline C; Miranda, Jose Carlos; Barral, Aldina; Tacchini-Cottier, Fabienne

2014-01-01

During a blood meal, Lutzomyia intermedia sand flies transmit Leishmania braziliensis, a parasite causing tegumentary leishmaniasis. In experimental leishmaniasis, pre-exposure to saliva of most blood-feeding sand flies results in parasite establishment in absence of any skin damages in mice challenged with dermotropic Leishmania species together with saliva. In contrast, pre-immunization with Lu. intermedia salivary gland sonicate (SGS) results in enhanced skin inflammatory exacerbation upon co-inoculation of Lu. intermedia SGS and L. braziliensis. These data highlight potential unique features of both L. braziliensis and Lu. intermedia. In this study, we investigated the genes modulated by Lu. intermedia SGS immunization to understand their potential impact on the subsequent cutaneous immune response following inoculation of both SGS and L. braziliensis. The cellular recruitment and global gene expression profile was analyzed in mice repeatedly inoculated or not with Lu. intermedia. Microarray gene analysis revealed the upregulation of a distinct set of IFN-inducible genes, an immune signature not seen to the same extent in control animals. Of note this INF-inducible gene set was not induced in SGS pre-immunized mice subsequently co-inoculated with SGS and L. braziliensis. These data suggest the parasite prevented the upregulation of this Lu. intermedia saliva-related immune signature. The presence of these IFN-inducible genes was further analyzed in peripheral blood mononuclear cells (PBMCs) sampled from uninfected human individuals living in a L. braziliensis-endemic region of Brazil thus regularly exposed to Lu. intermedia bites. PBMCs were cultured in presence or absence of Lu. intermedia SGS. Using qRT-PCR we established that the IFN-inducible genes induced in the skin of SGS pre-immunized mice, were also upregulated by SGS in PBMCs from human individuals regularly exposed to Lu. intermedia bites, but not in PBMCs of control subjects. These data demonstrate

Search efficiency of Spalangia cameroni and Muscidifurax raptor on Musca domestica pupae in dairy cattle farms in Denmark

DEFF Research Database (Denmark)

Skovgård, Henrik

2006-01-01

significantly to overall parasitism, M. raptor had a significantly higher attack rate when first a female had located bags with sentinel pupae. Based on the above results, however, S. cameroni seems the most appropriate species for managing house flies in straw bedded dairy cattle farms in Denmark. A biological......Indoor releases of Spalangia cameroni Perkins and Muscidifurax raptor Girauelt & Sanders (Hymenoptera: Pteromalidae) were conducted in five organic dairy cattle farms to evaluate the overall effect on parasitism and efficiency at different pupal depths of Musca domestica L. (Diptera: Muscidae...... control strategy of simultaneous releases of S. cameroni and M. raptor is discussed. Key words: biological control, dairy cattle, dispersion, parasitism, Phygadeuon fumat...

The veterinary drug ivermectin influences immune response in the yellow dung fly (Scathophaga stercoraria)

International Nuclear Information System (INIS)

West, Helen M.; Tracy, Saoirse R.

2009-01-01

Phenoloxidase (PO) is a key enzyme involved in the immune response of insects. We show that egg-to-adult exposure to residues of 0.001, but not 0.0005 mg kg -1 ivermectin elevated PO activity in yellow dung flies (Scathophaga stercoraria) developing in cattle dung. Fly fat content was unaffected by the treatments. Therefore, the response of PO was a direct effect of ivermectin and not an indirect one caused by an alteration in body 'condition'. This supports the non-intuitive conclusion that flies surviving exposure to faecal residues may have enhanced immune function. To our knowledge, this is the first study to assess the effects on PO activity of insecticidal residues in livestock dung. The non-target effects of such residues are of wide interest, given the global use of veterinary products. - Phenoloxidase activity in Scathophaga stercoraria is enhanced by ivermectin and that effect is transferred to the adult fly from the larval stage

Flebotomíneos de Timóteo, Estado de Minas Gerais, Brasil (Diptera: Psychodidae Sand flies in Timóteo, Minas Gerais, Brazil (Diptera: Psychodidae

Directory of Open Access Journals (Sweden)

José Dilermando Andrade Filho

1997-10-01

Full Text Available Casos esporádicos de leishmaniose tegumentar têm ocorrido no Município de Timóteo, Minas Gerais, basicamente na população rural. Para conhecer a fauna de flebotomíneos da região, foram instaladas sete armadilhas luminosas de New Jersey na cidade, em sete diferentes bairros. As coletas foram realizadas no período de junho a outubro de 1994, dezembro de 1994 e janeiro a março de 1995, com um total de 3.240 horas por armadilha. Foram capturados 4.396 flebotomíneos, distribuídos em dois gêneros e vinte espécies: Brumptomyia cunhai, Brumptomyia nitzulescui, Lutzomyia (Nyssomyia whitmani, Lutzomyia (Nyssomyia intermedia, Lutzomyia quinquefer, Lutzomyia lenti, Lutzomyia (Pintomyia fischeri, Lutzomyia migonei, Lutzomyia sallesi, Lutzomyia termitophila, Lutzomyia aragaoi, Lutzomyia borgmeieri, Lutzomyia (Psathyromyia lutziana, Lutzomyia (Sciopemyia sordellii, Lutzomyia (Pintomyia pessoai, Lutzomyia (Trichopygomyia longispina, Lutzomyia misionensis, Lutzomyia (Psychodopygus davisi, Lutzomyia lanei, Lutzomyia (Pressatia sp. A espécie L. (N. whitmani foi a mais freqüente com 52,12%, seguida de L. (N. intermedia com 34,10%, e ambas podem estar participando da transmissão de leishmaniose cutânea na região.Sporadic cases of tegumentary leishmaniasis have occurred in Timóteo, Minas Gerais State, basically among the rural population. In order to study the region's sand fly population, New Jersey light traps were set in seven different neighborhoods. Specimens were gathered from June through October 1994, December 1994, and January through March 1995, with a total of 3,240 hours per trap. A total of 4,396 sand flies were captured, distributed among two genera and twenty species: Brumptomyia cunhai, Brumptomyia nitzulescui, Lutzomyia (Nyssomyia whitmani, Lutzomyia (Nyssomyia intermedia, Lutzomyia quinquefer, Lutzomyia lenti, Lutzomyia (Pintomyia fischeri, Lutzomyia migonei, Lutzomyia sallesi, Lutzomyia termitophila, Lutzomyia aragaoi, Lutzomyia

Incidence of Old World screw-worm fly, Chrysomya bezziana in Iraq

International Nuclear Information System (INIS)

Al-Taweel, Ayad A.; Al-Izzi, Mohammed A.J.; Jassim, Fadhil A.

2000-01-01

The Old World screw-worm fly (OWSWF), Chrysomya bezziana Villenuve, is a member of the insect family Calliphoridae and is an obligate parasite of warm-blooded animals in the tropics and sub-tropics (Norris and Murray 1964). Flies lay their eggs on the edge of wounds or body orifices; the resulting larvae invade the host tissues and produce lesions and infertility if the genitals become infested (Humphrey et al. 1980). Recorded hosts include cattle (Bos indicus), sheep (Ovis aries), goats (Caprus hircus), dogs (Canis familiaris), cats (Felis domesticus) and man (Homo sapiens) (Patton 1920, 1922, Stoddar and Peck 1962, Norris and Murray 1964). This investigation describes the incidence of myiasis caused by C. bezziana in Iraq from September 1996 to March 1998

The flagellar protein FLAG1/SMP1 is a candidate for Leishmania-sand fly interaction.

Science.gov (United States)

Di-Blasi, Tatiana; Lobo, Amanda R; Nascimento, Luanda M; Córdova-Rojas, Jose L; Pestana, Karen; Marín-Villa, Marcel; Tempone, Antonio J; Telleria, Erich L; Ramalho-Ortigão, Marcelo; McMahon-Pratt, Diane; Traub-Csekö, Yara M

2015-03-01

Leishmaniasis is a serious problem that affects mostly poor countries. Various species of Leishmania are the agents of the disease, which take different clinical manifestations. The parasite is transmitted by sandflies, predominantly from the Phlebotomus genus in the Old World and Lutzomyia in the New World. During development in the gut, Leishmania must survive various challenges, which include avoiding being expelled with blood remnants after digestion. It is believed that attachment to the gut epithelium is a necessary step for vector infection, and molecules from parasites and sand flies have been implicated in this attachment. In previous work, monoclonal antibodies were produced against Leishmania. Among these an antibody was obtained against Leishmania braziliensis flagella, which blocked the attachment of Leishmania panamensis flagella to Phlebotomus papatasi guts. The protein recognized by this antibody was identified and named FLAG1, and the complete FLAG1 gene sequence was obtained. This protein was later independently identified as a small, myristoylated protein and called SMP1, so from now on it will be denominated FLAG1/SMP1. The FLAG1/SMP1 gene is expressed in all developmental stages of the parasite, but has higher expression in promastigotes. The anti-FLAG1/SMP1 antibody recognized the flagellum of all Leishmania species tested and generated the expected band by western blots. This antibody was used in attachment and infection blocking experiments. Using the New World vector Lutzomyia longipalpis and Leishmania infantum chagasi, no inhibition of attachment ex vivo or infection in vivo was seen. On the other hand, when the Old World vectors P. papatasi and Leishmania major were used, a significant decrease of both attachment and infection were seen in the presence of the antibody. We propose that FLAG1/SMP1 is involved in the attachment/infection of Leishmania in the strict vector P. papatasi and not the permissive vector L. longipalpis.

Intradomiciliary and peridomiciliary captures of sand flies (Diptera: Psychodidae) in the leishmaniasis endemic area of Chapare province, tropic of Cochabamba, Bolivia.

Science.gov (United States)

Ballart, C; Vidal, G; Picado, A; Cortez, M R; Torrico, F; Torrico, M C; Godoy, R E; Lozano, D; Gállego, M

2016-02-01

In South America, cutaneous leishmaniasis is the most frequent clinical form of leishmaniasis. Bolivia is one of the countries with higher incidence, with 33 cases per 100,000 individuals, and the disease is endemic in 70% of the territory. In the last decade, the number of cases has increased, the age range has expanded, affecting children under 5 years old, and a similar frequency between men and women is found. An entomological study with CDC light traps was conducted in three localities (Chipiriri, Santa Elena and Pedro Domingo Murillo) of the municipality of Villa Tunari, one of the main towns in the Chapare province (Department of Cochabamba, Bolivia). A total of 16 specimens belonging to 6 species of the genus Lutzomyia were captured: Lu. aragaoi, Lu. andersoni, Lu. antunesi, Lu. shawi, Lu. yuilli yuilli and Lu. auraensis. Our results showed the presence of two incriminated vectors of leishmaniasis in an urbanized area and in the intradomicile. More entomological studies are required in the Chapare province to confirm the role of vector sand flies, the intradomiciliary transmission of the disease and the presence of autochthonous cases of cutaneous leishmaniasis. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of Fatty Acid and Geraniol Repellent-Oil Mixtures Applied to Cattle on Blood Feeding and Reproductive Parameters in Field Populations of Haematobia irritans (Diptera: Muscidae).

Science.gov (United States)

Mullens, Bradley A; Soto, Diane; Gerry, Alec C; Fowler, Fallon E; Diniz, Alesha N

2018-02-28

California pastured cattle were treated with 250 ml of a 15% mixture of fatty acids (C8-C9-C10) or 125 ml of 2% geraniol in a mineral oil carrier to assess impacts on horn flies, Haematobia irritans (L.) (Diptera: Muscidae) over two summers. Horn flies were netted from cattle every 3-4 d for 2 wk before treatment, 2 wk during treatment (four treatments, with flies collected before each treatment), and 2 wk after treatments ceased. Blood meal weights were estimated by hemoglobin assay of excised abdomens. Other females were dissected to determine the number of active ovarioles and the stage of primary follicle development. Depending on year and herd, pretreatment males contained an average of 0.6-1.0 mg of blood, while females contained 1.7-2.7 mg. Pretreatment egg development (least developed oocytes were stage 1 and fully developed eggs were stage 5) averaged 3.7-4.3, and number of active ovarioles averaged 18.1 to 19.6/female. During treatment periods, significant reductions in blood weight were noted for females, but usually not for males, and females also often exhibited reduced mean oocyte stage and number of active ovarioles. Peaks in proportions of young nulliparous females (oocyte stages 1 or 2) were seen during some repellent application periods. This suggested older females had been killed or driven off from the local population by the treatments, and flies on cattle included more young flies that likely were recent arrivals. The repellent-oil mixture thus impacted blood feeding, reproductive fitness, and probably age structure in the field.

Effects of the botanical compound p-anisaldehyde on horn fly, Haematobia irritans irritans (L.) (Diptera: Muscidae) repellency, mortality, and reproduction

Science.gov (United States)

The horn fly, Haematobia irritans irritans (L.), is an economically important obligate blood-feeding ectoparasite that mainly attacks cattle worldwide. As resistance to conventional insecticides increases, alternative control tactics are being investigated. p-Anisaldehyde occurs in many plants and i...

Protecting cows in small holder farms in East Africa from tsetse flies by mimicking the odor profile of a non-host bovid.

Directory of Open Access Journals (Sweden)

Rajinder K Saini

2017-10-01

Full Text Available For the first time, differential attraction of pathogen vectors to vertebrate animals is investigated for novel repellents which when applied to preferred host animals turn them into non-hosts thereby providing a new paradigm for innovative vector control. For effectively controlling tsetse flies (Glossina spp., vectors of African trypanosomosis, causing nagana, repellents more powerful than plant derived, from a non-host animal the waterbuck, Kobus ellipsiprymnus defassa, have recently been identified. Here we investigate these repellents in the field to protect cattle from nagana by making cattle as unattractive as the buck.To dispense the waterbuck repellents comprising guaiacol, geranylacetone, pentanoic acid and δ-octalactone, (patent application we developed an innovative collar-mounted release system for individual cattle. We tested protecting cattle, under natural tsetse challenge, from tsetse transmitted nagana in a large field trial comprising 1,100 cattle with repellent collars in Kenya for 24 months. The collars provided substantial protection to livestock from trypanosome infection by reducing disease levels >80%. Protected cattle were healthier, showed significantly reduced disease levels, higher packed cell volume and significantly increased weight. Collars >60% reduced trypanocide use, 72.7% increase in ownership of oxen per household and enhanced traction power (protected animals ploughed 66% more land than unprotected. Land under cultivation increased by 73.4%. Increase in traction power of protected animals reduced by 69.1% acres tilled by hand per household per ploughing season. Improved food security and household income from very high acceptance of collars (99% motivated the farmers to form a registered community based organization promoting collars for integrated tsetse control and their commercialization.Clear demonstration that repellents from un-preferred hosts prevent contact between host and vector, thereby

Relating zoobenthic and emergent terrestrial insect production to tree swallow (Tachycineta bicolor) nestling diet in oil sands wetlands

Energy Technology Data Exchange (ETDEWEB)

Thoms, J.L.; Martin, J.P.; Ciborowski, J.J. [Windsor Univ., Windsor, ON (Canada); Harms, N.J.; Smits, J.E. [Saskatchewan Univ., Saskatoon, SK (Canada)

2009-07-01

This study examined the influence of oil sands process materials (OSPM) on wetland macroinvertebrate community composition and production. Tree swallows are known to inhabit constructed nest boxes and forage near their nest on flying insects of terrestrial and aquatic origin. Therefore, this study evaluated the structure of wetland food webs and how it relates to the transfer of production from aquatic sediments to nestling tree swallows. The study involved 2 reference and 2 oil sands affected wetlands. Exuviae of emerging aquatic and flying insects from floating and sticky traps were collected every 3 days during the tree swallow nestling period in order to estimate benthic invertebrate composition and production. The tree swallow nest boxes, placed around the perimeter of the wetlands in spring were monitored during egg laying and incubation. Diets of the 10-14 day-old nestlings were determined by placing a ligature around the neck of each nestling, preventing the passage of food into the esophagus for 45 min. Food boluses were collected from nestlings fed by the parents during that time. The study showed that although oil sands-affected wetlands had lower aerial insect abundance, they represented over half of the total boluses collected. It was concluded that this study will help determine the ecological viability of oil sands-affected wetlands and their capability of supporting terrestrial predators that rely on zoobenthos.

EXPERIMENTAL DETERMINATION OF VARIABILITY IN PERMEABILITY OF SANDY SILT SOIL MIXED WITH FLY ASH IN PROPORTIONATE

OpenAIRE

Rasna Sharma*, Dr. M.K. Trivedi

2016-01-01

This paper presents the experimental determination of variability in permeability of sandy silt soil by blending with fly ash. The grain size, porosity, structure of the soil, specific gravity of the soil, viscosity and temperature are important factors in varying the permeability of the soil. Permeability is the flow conduction property of the soil. The void ratio with in the soil plays a vital role in varying the permeability. By blending with finer grains like fly ash in the soil with sand...

Influence green sand system by core sand additions

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N. Špirutová

2012-01-01

Full Text Available Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this contribution is: “How the green sand systems are influenced by core sands?”This effect is considered by determination of selected technological properties and degree of green sand system re-bonding. From the studies, which have been published yet, there is not consistent opinion on influence of core sand dilution on green sand system properties. In order to simulation of the effect of core sands on the technological properties of green sands, there were applied the most common used technologies of cores production, which are based on bonding with phenolic resin. Core sand concentration added to green sand system, was up to 50 %. Influence of core sand dilution on basic properties of green sand systems was determined by evaluation of basic industrial properties: moisture, green compression strength and splitting strength, wet tensile strength, mixture stability against staling and physical-chemistry properties (pH, conductivity, and loss of ignition. Ratio of active betonite by Methylene blue test was also determined.

Natural radionuclides near a coal-fired power station. [/sup 210/Po and /sup 210/Pb levels in cattle livers

Energy Technology Data Exchange (ETDEWEB)

Smith-Briggs, J L; Crick, M J [National Radiological Protection Board, Harwell (UK)

1982-11-01

Previous measurements have shown enhanced levels of /sup 210/Po and /sup 210/Pb from fly ash deposited in the environment around old coal-fired power stations. Preliminary results are presented for levels of /sup 210/Po and /sup 210/Pb in liver samples from cattle which had grazed for two to three years in a field adjacent to a modern power station. No significant difference in the levels of these natural radionuclides was found compared to liver samples obtained from cattle in a control area.

Expectations of Cattle Feeding Investors in Feeder Cattle Placements

OpenAIRE

Kastens, Terry L.; Schroeder, Ted C.

1993-01-01

Cattle feeders appear irrational when they place cattle on feed when projected profits are negative. Long futures positions appear to offer superior returns to cattle feeding investment. Cattle feeder behavior suggests that they believe a downward bias in live cattle futures persists and that cattle feeders use different information than the live cattle futures market price when making placement decisions. This paper examines feeder cattle placement determinants and compares performance of ex...

Solidification/stabilization of ASR fly ash using Thiomer material: Optimization of compressive strength and heavy metals leaching.

Science.gov (United States)

Baek, Jin Woong; Choi, Angelo Earvin Sy; Park, Hung Suck

2017-12-01

Optimization studies of a novel and eco-friendly construction material, Thiomer, was investigated in the solidification/stabilization of automobile shredded residue (ASR) fly ash. A D-optimal mixture design was used to evaluate and optimize maximum compressive strength and heavy metals leaching by varying Thiomer (20-40wt%), ASR fly ash (30-50wt%) and sand (20-40wt%). The analysis of variance was utilized to determine the level of significance of each process parameters and interactions. The microstructure of the solidified materials was taken from a field emission-scanning electron microscopy and energy dispersive X-ray spectroscopy that confirmed successful Thiomer solidified ASR fly ash due to reduced pores and gaps in comparison with an untreated ASR fly ash. The X-ray diffraction detected the enclosed materials on the ASR fly ash primarily contained sulfur associated crystalline complexes. Results indicated the optimal conditions of 30wt% Thiomer, 30wt% ASR fly ash and 40wt% sand reached a compressive strength of 54.9MPa. For the optimum results in heavy metals leaching, 0.0078mg/LPb, 0.0260mg/L Cr, 0.0007mg/LCd, 0.0020mg/L Cu, 0.1027mg/L Fe, 0.0046mg/L Ni and 0.0920mg/L Zn were leached out, being environmentally safe due to being substantially lower than the Korean standard leaching requirements. The results also showed that Thiomer has superiority over the commonly used Portland cement asa binding material which confirmed its potential usage as an innovative approach to simultaneously synthesize durable concrete and satisfactorily pass strict environmental regulations by heavy metals leaching. Copyright © 2017 Elsevier Ltd. All rights reserved.

Insurance against an Old World screw-worm fly invasion of Australia

International Nuclear Information System (INIS)

Tweddle, Neil; Mahon, Rod J.

2000-01-01

Australia is fortunate that neither the New World screw-worm fly Cochliomyia hominivorax (Coquerel) (NWSWF) nor the Old World screw-worm fly, Chrysomya bezziana Villeneuve (OWSWF), have become established within our country, although much of the northern areas are environmentally suitable (Suthurst et al. 1989). The OWSWF is a substantial threat as it is prevalent in the neighbouring countries of Papua New Guinea and Indonesia. Perhaps more importantly, it is also present in many of our trading partners in Southeast Asia. The export of live cattle from northern Australian ports to Southeast Asian nations has become an important and rapidly expanding trade. The fly is also present near ports in the Middle East which receive considerable numbers of live sheep exported from various Australian ports. In both situations, there is the ever-present opportunity for the screw-worm fly (SWF) to return to Australia as larvae, pupae or adults on stock carrying vessels. While this means of transport probably represents the most likely route for the pest to gain access to Australia, accidental transport on aircraft and active myiases on humans or companion animals remain possibilities. The introduction of the NWSWF into Australia is considered unlikely, but not impossible. Indeed, in 1992, an Australian tourist returning from South America carried live NWSWF larvae into Australia in a neck wound. Fortunately, the diagnosis was made early and the wound was treated, preventing any larvae evacuating. This was in southern Australia in May, where climatic conditions are unlikely to favour survival at that time of the year, but it demonstrates the potential for inadvertent introduction. Models of the impact of the OWSWF indicate that the cost of an invasion would be high. It has been estimated by Anaman et al. (1993), that the annual cost in an average climate year to beef cattle, sheep and dairy producers of an endemic establishment would be A$281 million. These costs would be

Pyrosequencing-based analysis of the microbiome associated with the horn fly, Haematobia irritans.

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Azhahianambi Palavesam

Full Text Available The horn fly, Haematobia irritans, is one of the most economically important pests of cattle. Insecticides have been a major element of horn fly management programs. Growing concerns with insecticide resistance, insecticide residues on farm products, and non-availability of new generation insecticides, are serious issues for the livestock industry. Alternative horn fly control methods offer the promise to decrease the use of insecticides and reduce the amount of insecticide residues on livestock products and give an impetus to the organic livestock farming segment. The horn fly, an obligatory blood feeder, requires the help of microflora to supply additional nutrients and metabolize the blood meal. Recent advancements in DNA sequencing methodologies enable researchers to examine the microflora diversity independent of culture methods. We used the bacterial 16S tag-encoded FLX-titanium amplicon pyrosequencing (bTEFAP method to carry out the classification analysis of bacterial flora in adult female and male horn flies and horn fly eggs. The bTEFAP method identified 16S rDNA sequences in our samples which allowed the identification of various prokaryotic taxa associated with the life stage examined. This is the first comprehensive report of bacterial flora associated with the horn fly using a culture-independent method. Several rumen, environmental, symbiotic and pathogenic bacteria associated with the horn fly were identified and quantified. This is the first report of the presence of Wolbachia in horn flies of USA origin and is the first report of the presence of Rikenella in an obligatory blood feeding insect.

The seaweed fly (Coelopidae) can facilitate environmental survival and transmission of E. coli O157 at sandy beaches.

Science.gov (United States)

Swinscoe, Isobel; Oliver, David M; Gilburn, Andre S; Quilliam, Richard S

2018-06-19

The sustainable management of recreational beaches is essential for minimising risk of human exposure to microbial pathogens whilst simultaneously maintaining valuable ecosystem services. Decaying seaweed on public beaches is gaining recognition as a substrate for microbial contamination, and is a potentially significant reservoir for human pathogens in close proximity to beach users. Closely associated with beds of decaying seaweed are dense populations of the seaweed fly (Coelopidae), which could influence the spatio-temporal fate of seaweed-associated human pathogens within beach environments. Replicated mesocosms containing seaweed inoculated with a bioluminescent strain of the zoonotic pathogen E. coli O157:H7, were used to determine the effects of two seaweed flies, Coelopa frigida and C. pilipes, on E. coli O157:H7 survival dynamics. Multiple generations of seaweed flies and their larvae significantly enhanced persistence of E. coli O157:H7 in simulated wrack habitats, demonstrating that both female and male C. frigida flies are capable of transferring E. coli O157:H7 between individual wrack beds and into the sand. Adult fly faeces can contain significant concentrations of E. coli O157:H7, which suggests they are capable of acting as biological vectors and bridge hosts between wrack habitats and other seaweed fly populations, and facilitate the persistence and dispersal of E. coli O157:H7 in sandy beach environments. This study provides the first evidence that seaweed fly populations inhabiting natural wrack beds contaminated with the human pathogen E. coli O157:H7 have the capacity to amplify the hazard source, and therefore potential transmission risk, to beach users exposed to seaweed and sand in the intertidal zone. The risk to public health from seaweed flies and decaying wrack beds is usually limited by human avoidance behaviour; however, seaweed fly migration and nuisance inland plagues in urban areas could increase human exposure routes beyond the

Field assessment of synthetic attractants and traps for the Old World screw-worm fly, Chrysomya bezziana.

Science.gov (United States)

Urech, R; Green, P E; Brown, G W; Spradbery, J P; Tozer, R S; Mayer, D G; Tack Kan, Y

2012-07-06

The performance of newly developed trapping systems for the Old World screw-worm fly, Chrysomya bezziana has been determined in field trials on cattle farms in Malaysia. The efficacy of non-sticky traps and new attractants to trap C. bezziana and non-target flies was compared with the standard sticky trap and Swormlure. The optimal trap was a modified LuciTrap(®) with a new attractant mixture, Bezzilure-2. The LuciTrap/Bezzilure-2 caught on average 3.1 times more C. bezziana than the sticky trap with Swormlure (PChrysomya megacephala and Chrysomya rufifacies with factors of 5.9 and 6.4, respectively. The LuciTrap also discriminates with factors of 90 and 3.6 against Hemipyrellia sp. and sarcophagid flesh flies respectively, compared to the sticky trap. The LuciTrap/Bezzilure-2 system is recommended for screwworm fly surveillance as it is more attractive and selective towards C. bezziana and provides flies of better quality for identification than the sticky trap. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

Estimation of resource savings due to fly ash utilization in road construction

Energy Technology Data Exchange (ETDEWEB)

Kumar, Subodh; Patil, C.B. [Centre for Energy Studies, Indian Institute of Technology, New Delhi 110016 (India)

2006-08-15

A methodology for estimation of natural resource savings due to fly ash utilization in road construction in India is presented. Analytical expressions for the savings of various resources namely soil, stone aggregate, stone chips, sand and cement in the embankment, granular sub-base (GSB), water bound macadam (WBM) and pavement quality concrete (PQC) layers of fly ash based road formation with flexible and rigid pavements of a given geometry have been developed. The quantity of fly ash utilized in these layers of different pavements has also been quantified. In the present study, the maximum amount of resource savings is found in GSB followed by WBM and other layers of pavement. The soil quantity saved increases asymptotically with the rise in the embankment height. The results of financial analysis based on Indian fly ash based road construction cost data indicate that the savings in construction cost decrease with the lead and the investment on this alternative is found to be financially attractive only for a lead less than 60 and 90km for flexible and rigid pavements, respectively. (author)

Single and concomitant experimental infectionsby Endotrypanum spp. and Leishmania (Viannia guyanensis (Kinetoplastida: Trypanosomatidae in the Neotropical sand fly Lutzomyia longipalpis (Diptera: Psychodidae

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André F Barbosa

2006-12-01

Full Text Available Lutzomyia longipalpis females received single and mixed infections with Endotrypanum and Leishmania. Two biological parameters were analyzed: the percentage of infected females and the distribution of flagellates in the gut of the females. The principal comparisons were performed between (1 two strains of Endotrypanum, (2 cloned versus primary sample of one strain of Endotrypanum, (3 Endotrypanum versus Leishmania guyanensis, and (4 the pattern of flagellates behaviour by optical microscopy in females with single or mixed infection versus the identification of parasites isolated from digestive tracts by isoenzyme electrophoresis. Flagellates of Endotrypanum showed distinct patterns of infection suggesting that there is variation between and within strains. The distribution of Endotrypanum and L. guyanensis differed significantly in relation to the colonization of the stomodeal valve. In co-infection with L. guyanensis, a large number of flagellates were seen to be plentifully infecting the stomodeal valve in significantly more specimens than in females infected by Endotrypanum only. However, the electrophoretic profiles of isoenzymes of parasites recovered from all co-infected specimens corresponded to Endotrypanum. This suggests that the mere correlation sand fly infection-biochemical analysis of isolates may induce parasitological incorrect consideration.

The salivary glands of two sand fly vectors of Leishmania: Lutzomyia migonei (França) and Lutzomyia ovallesi (Ortiz)(Diptera: Psychodidae).

Science.gov (United States)

Nieves, Elsa; Buelvas, Neudo; Rondón, Maritza; González, Néstor

2010-01-01

Leishmaniasis is a vector-borne disease transmitted by the intradermal inoculation of Leishmania (Kinetoplastida: Trypanosomatidae) promastigotes together with saliva during the bite of an infected sand fly. The salivary glands were compared from two vector species, Lutzomyia ovallesi (Ortiz,1952) and Lutzomyia migonei (França,1920) (Diptera: Psychodidae). Protein profiles by SDS PAGE of salivary glands were compared among species as well as their development at several times post feeding. First, mice were immunized to salivary proteins by exposure to biting by L. ovallesi and of L. migonei. Antibodies in these mice against salivary gland-specific proteins were evaluated by immunoblotting. No apparent change was revealed in the kinetic expression of salivary proteins induced by the different physiological states post feeding. Qualitative and quantitative variations were detected in16-18 polypeptides with molecular weights ranging from 6 to 180 kDa. Species-specific proteins were demonstrated for L. migonei and L. ovallesi. In addition, antibodies against salivary gland specific proteins were found in mice immunized by the saliva of both species. Basic information was obtained concerning the nature of salivary gland proteins of L. migonei and L. ovallesi. This information helps to elucidate the role of salivary proteins and their potential as effective tools in screening risk factors in human and other vertebrate hosts.

Experimental Investigations of Effect of Sulphur on Beach Sand–Fly Ash–Asphalt (S-F-A Paving Mixes

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Satyakumar, M.

2013-01-01

Full Text Available The main components of the flexible pavements are asphalt and aggregates. But in most of the places in India there is shortage of the good quality aggregates (especially coarse aggregates, at the same time beach sand is available in plenty in many regions. Due to relative abundance of beach sand, the studies on the utilities of the beach sand in paving mixes are worth taking up. But beach Sand-Asphalt mix alone is not suitable for pavement construction, because of its low stability and high air voids. In the present study, Sand-Fly ash-Asphalt-Sulphur (S-F-A-S mixes are being made in different proportions and tested for their properties. Fatigue strength, stability, water sensitivity, stiffness modulus and dynamic modulus tests are carried out at standard test conditions and the results are analyzed for drawing conclusions. This study investigates the potential use of abundant ingredients, which may replace the ones which are scarce in nature.

Dynamics of deposited fly-ash and fine grained magnetite in sandy material of different porosity (column experiments)

Science.gov (United States)

Kapicka, Ales; Kodesova, Radka; Petrovsky, Eduard; Grison, Hana

2010-05-01

Several studies confirm that soil magnetometry can serve as proxy of industrial immisions as well as heavy-metal contamination. The important assumption for magnetic mapping of contaminated soils is that atmospherically deposited particulate matter, including the ferrimagnetic phase, accumulates in the top soil horizons and remains there over long period. Only if this is true, large areas can be reliably mapped using soil magnetometry, and, moreover, this method can be used also for long-term monitoring. However, in soil types such as sandy soils with different porosity or soils with substantial variability of water regime, translocation of the deposited anthropogenic particles may result in biased (underestimated) values of the measured topsoil magnetic susceptibility. From the physical point of view, this process may be considered as colloid transport through porous medium. In our column experiments in laboratory we used three technical sands with different particle sizes (0,63 - 1.25mm, 0,315-0,80mm, 0,10-0,63mm). Sands in cylinders were contaminated on the surface by fly-ashes from coal-burning power plant (mean grain size 10μm) and fine grained Fe3O4 (grain size < 20 μm). Soil moisture sensors were used to monitor water regime within the sand columns after controlled rain simulation and temperature distribution in sand column was measured as well. Vertical migration of ferrimagnetic particles-tracers presented in the fly-ash was measured by SM 400 Kappameter. By means of magnetic susceptibility distribution we studied two parameters: gradual shift of peak concentration of contaminants (relative to surface layer) and maximum penetration depth. Results indicated that after rain simulation (pulls infiltration of defined water volume) the positions of peak values moved downwards compared to the initial state and gradual decrease of susceptibility peak values were detected in all studied sand formations. Fly-ash migrated more or less freely in coarse sand

A Cross-Sectional Survey of Knowledge, Attitude and Practices Related to Cutaneous Leishmaniasis and Sand Flies in Punjab, Pakistan.

Directory of Open Access Journals (Sweden)

Ayesha Akram

Full Text Available Recent outbreaks of cutaneous leishmaniasis make the disease a public health concern in Punjab, Pakistan. The knowledge of how the population perceives the disease and its vector is essential in order to design an effective management strategy, but such studies are rare in Pakistan.The present study was based on a cross-sectional self-administered survey comprising 250 household samples collected from five localities including Bhawalpur, Multan, Jhang, Faisalabad and Lahore. The results revealed that the respondents had a poor knowledge of the vector and disease. Few of the respondents were aware about the identification of sand flies, their breeding place, biting time, transmission of leishmaniasis and control measures. Skin infection and sandflies as the main disease symptom and vector of the disease, respectively, were known to some of the respondents. Some believed that summer was the main peak incidence of the disease and it could be transmitted from man to man via contact. However, most of the respondents believed that the disease could be cured. Admission to hospitals, cleanliness and use of bed nets were the treatment measures for the disease in suspected patients, whereas some thought that the use of bed nets could be helpful in preventing leishmaniasis infection.Poor knowledge of the disease and its vector in the study population emphasize the need to initiate health education and awareness campaigns to minimize the risks of cutaneous leishmaniasis outbreaks in the future.

Effects of pyriproxyfen and buprofezin on immature development and reproduction in the stable fly.

Science.gov (United States)

Liu, S S; Li, A Y; Lohmeyer, K H; Pérez De León, A A

2012-12-01

The stable fly, Stomoxys calcitrans (L.) (Diptera: Muscidae), is one of the most significant biting flies that affect cattle. The use of traditional insecticides for stable fly control has only a limited success owing to the insect's unique feeding behaviours and immature development sites. A laboratory study was conducted to evaluate the effects of two insect growth regulator (IGR) products, pyriproxyfen and buprofezin, on the development of the immature stages of the stable fly and the effects of pyriproxyfen on oviposition and egg hatch. Both pyriproxyfen and buprofezin had significant inhibitory effects on immature development. The LC(50) s of pyriproxyfen and buprofezin were 0.002 and 18.92 p.p.m., respectively. Topical treatment of adult females with different doses of pyriproxyfen had significant negative effects on both female oviposition and egg hatching when 1- and 3-day-old females were treated, and the effects were dose dependent. A significant reduction in the mean number of eggs laid was observed only at the highest pyriproxyfen dose (8 µg/fly) and egg hatch was unaffected by pyriproxyfen treatment when 5-day-old females were treated. Results from the present study indicate that pyriproxyfen has the potential to be used as part of an integrated stable fly management programme. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Self mixing of fly larvae during feeding

Science.gov (United States)

Shishkov, Olga; Johnson, Christopher; Hu, David

How do we sustainably feed a growing world population? One solution of increasing interest is the use of black solider fly larvae, pea-sized grubs envisioned to transform hundreds of tons of food waste into a sustainable protein source. Although startups across the world are raising these larvae, a physical understanding of how they should be raised and fed remains missing. In this study, we present experiments measuring their feeding rate as a function of number of larvae. We show that larger groups of larvae have greater mixing which entrains hungry larvae around the food, increasing feeding rate. Feeding of larvae thus differs from feeding of cattle or other livestock which exhibit less self-mixing.

Macroscopic digestive tract anatomy of two small antelopes, the blackbuck (Antilope cervicapra) and the Arabian sand gazelle (Gazella subgutturosa marica)

DEFF Research Database (Denmark)

Sauer, Cathrine; Bertelsen, Mads Frost; Hammer, Sven

2016-01-01

The digestive tract anatomy of 14 blackbucks (Antilope cervicapra) and 7 Arabian sand gazelles (Gazella subgutturosa marica) was quantified by dimensions, area and weight. Data from the two small-sized antilopinae were evaluated against a larger comparative data set from other ruminants classified...... as having either a ‘cattle-type’ or ‘moose-type’ digestive system. The digestive anatomy of the blackbuck resembled that of 'cattle-type' ruminants, which corresponds to their feeding ecology and previous studies of solute and particle retention time; however, a surprising exception was the remarkably small...... time had led to the expectation of a more 'cattle-type' anatomy. The results show that outliers to general morphological trends exist, that findings on physiology and anatomy do not always match completely, and that differences in the digestive morphology among ruminant species are more difficult...

New systems for the large-scale production of male tsetse flies (Diptera: Glossinidae)

International Nuclear Information System (INIS)

Opiyo, E.; Luger, D.; Robinson, A.S.

2000-01-01

Tsetse flies, vectors of trypanosomiasis, infest 36 African countries and their distribution covers approximately 10 million km 2 . Trypanosomiasis is a debilitating and often fatal disease of domestic livestock and humans and is considered the most important limiting factor for the development of the livestock sector in Africa. Approximately 50 million cattle and scores of millions of small ruminants are at risk of contracting trypanosomiasis. Direct losses in meat production, milk yield and traction power and the cost of control programmes are estimated to amount to more than US$500 million each year (FAO 1994). In addition, 100 million people are at risk of contracting the disease. According to the World Health Organization, about 300,000 new cases of human trypanosomiasis occur annually (WHO 1997). If the lost potential in livestock production is combined with that of crop production through loss of traction power, trypanosomiasis is estimated to cost Africa US$4 billion or more each year (FAO 1994). The available and environmentally accepted intervention methods for the management of tsetse and trypanosomiasis include parasite control using drugs, the promotion of trypanotolerant livestock and vector control. Parasite control is plagued by the development of resistance to the available drugs and programmes for the development of new drugs are limited. Vector control and eradication involve application of insecticide treated attractive devices on animals including cattle, and the sterile insect technique (SIT). In spite of the efforts spent on the control of the disease and the vector, tsetse flies remain a threat to agricultural development of the region. Experience indicates that only a combination of several of these intervention methods can effectively support sustainable agricultural systems. The feasibility of rearing tsetse flies in Africa for use in SIT was first demonstrated in Tanzania (Williamson et al. 1983) where a colony of 60,000 Glossina

Blood Collection from Local Abattoirs for Mass Production of Tsetse Flies to be used in the Sterile Insect Technique

Energy Technology Data Exchange (ETDEWEB)

Byamungu, M B; Kiimbisa, B; Matembo, S; Mashenga, G [Tsetse and Trypanosomiasis Research Institute, P.O. Box 1026, Tanga (Tanzania, United Republic of)

2012-07-15

The mass production of tsetse flies (Glossina spp.) for the sterile insect technique (SIT) requires a supply of quality blood. For some years already cattle blood has been used as food for laboratory reared flies. The blood is collected from an abattoir using standard procedures. The collection procedures, handling and storage require aseptic conditions to avoid contamination of the blood, which could be fatal to the flies. Fly mortality caused by low quality blood endangers the success of mass rearing. To rear healthy flies with good survival and production the blood should be of good quality - free of contamination and with a packed cell volume (PCV) above 25%. The present work involved the seasonal collection of blood from abattoirs in the United Republic of Tanzania (Tanga, Arusha, Dodoma, Dar-es-salaam). Dodoma was identified as having the best conditions for blood collection. To assess the quality of the blood as a diet for tsetse, blood was screened for the presence of bacteria, and the pathogens were identified. Protocols were developed for blood quality assurance. (author)

Balkan brachicerous cattle - the first domesticated cattle in Europe.

Science.gov (United States)

Hristov, Peter; Sirakova, Daniela; Mitkov, Ivan; Spassov, Nikolai; Radoslavov, Georgi

2018-01-01

The present study aimed to compare mitochondrial diversity among Balkan Neolithic/Chalcolithic cattle and present day Shorthorn Rhodopean cattle (Busha) to throw a new insight into European cattle domestication. The results showed that both ancient- and present-day samples belonged to the macrohaplogroup T. From the 28 sequences (8 ancient and 20 modern), the T1 and T2 haplogroup represent about 3.6% (1/28; 1/28). The T3 haplogroup was with the highest frequency - 57% (16/28). Based on the SNPs on 16057A and 16133C, the new T6 haplogroup was proposed. This haplogroup represents 75% from the ancient and 20% from the present day Bulgarian brachicerous cattle population. The survey in GenBank data base did not find a similar motif, except for the recent Serbian Busha cattle. Overall, these results showed that: (i) The newly named T6 haplogroup is Balkan specific; (ii) The T6 haplogroup survives in present day Bulgarian rhodopean cattle; (iii) The Balkan brachicerous cattle is the oldest European cattle breed.

Recovery of native prairie after pipeline construction in the Sand Hills region of Saskatchewan

International Nuclear Information System (INIS)

Walker, D.; Kremer, L.; Marshall, W.

1996-01-01

Land reclamation measures taken after construction of a large diameter natural gas pipeline in the Great Sand Hills region of southwestern Saskatchewan were detailed. Mitigation measures included modified construction procedures to minimize the size of the disturbance, worker educational programs to sensitize them to the prevailing fragile environment, dormant season construction, efforts to salvage topsoil seedbank, fertilizer application, straw bale wind barriers, brush mulch wind barriers, surface manipulation with the Hodder Gouger, fencing-out cattle, and the application of a seed mixture of agronomic legumes and native grasses. Vegetation and soil erosion were monitored over a period of four years. After four years the canopy cover was 88 per cent native species. On low-lying, protected sites vegetation was stable enough to support cattle grazing. Exposed sites will not reach this level of vegetation stability for some years to come due soil erosion by wind

Environmental Impacts of Sand Exploitation. Analysis of Sand Market

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Marius Dan Gavriletea

2017-06-01

Full Text Available Sand is an indispensable natural resource for any society. Despite society’s increasing dependence on sand, there are major challenges that this industry needs to deal with: limited sand resources, illegal mining, and environmental impact of sand mining. The purpose of this paper is twofold: to present an overview of the sand market, highlighting the main trends and actors for production, export and import, and to review the main environmental impacts associated with sand exploitation process. Based on these findings, we recommend different measures to be followed to reduce negative impacts. Sand mining should be done in a way that limits environmental damage during exploitation and restores the land after mining operations are completed.

Influence of Fly Ash on the Compressive Strength of Foamed Concrete at Elevated Temperature

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Ahmad H.

2014-01-01

Full Text Available Foamed concrete is a lightweight concrete that is widely used in the construction industry recently. This study was carried out to investigate the influence of fly ash as a cement replacement material to the residual compressive strength of foamed concrete subjected to elevated temperature. For this study, the foamed concrete density was fixed at 1300 kg/m3 and the sand-cement ratio and water-cement was set at 1:2 and 0.45, respectively. The samples were prepared and tested at the age of 28 days. Based on the results, it has been found that with 25% inclusion of fly ash, the percentage of compressive strength loss was decreased by 3 – 50%.

The effect of fly ash on the quality of mortars

Energy Technology Data Exchange (ETDEWEB)

Hovy, M F [Blue Circle Cement (Pty) Ltd., Industria West (South Africa)

1994-12-31

A comparative study of the commercially available blends of the fly cement was made. The focus of the research was to determine the suitability of fly ash blends in mortars. A comparative evaluation was made to establish the differences between laboratory analysis and on site practice. These comparisons were made using 4 different building sands. The laboratory evaluations were confined to specified test methods to determine the suitability of the mortar. However, the in-situ tests required an innovative approach such as: conducting tests on mortar joints to determine the in-situ compressive strengths. (A new technique was developed, which involves shooting nails into the mortar joint, determining the penetration depth and its pull out strength. This is then calibrated against cube strengths); and conducting tests using the SABS approach to determine the resistance to water penetration through a brick wall. The trends in the laboratory evaluations were as expected in terms of improved water demands, water retention and reduced compressive strengths. The in-situ mortar compressive strengths were marginally lower when using fly ash blends compared to ordinary portland cement. The use of fly ash blends improved the resistance of water penetration through a brick wall. In-situ tests are probably the only meaningful way to determine the effectiveness of a mortar in fulfilling its functions in a wall as laid down by SABS 0164:1990. With this in mind, the same quality or an improved quality mortar will be obtained using fly ash blended cements rather than ordinary portland cement. 10 refs., 13 figs., 5 tabs.

EFFECTS OF A SAND RUNNING SURFACE ON THE KINEMATICS OF SPRINTING AT MAXIMUM VELOCITY

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P E Alcaraz

2011-05-01

Full Text Available Performing sprints on a sand surface is a common training method for improving sprint-specific strength. For maximum specificity of training the athlete’s movement patterns during the training exercise should closely resemble those used when performing the sport. The aim of this study was to compare the kinematics of sprinting at maximum velocity on a dry sand surface to the kinematics of sprinting on an athletics track. Five men and five women participated in the study, and flying sprints over 30 m were recorded by video and digitized using biomechanical analysis software. We found that sprinting on a sand surface was substantially different to sprinting on an athletics track. When sprinting on sand the athletes tended to ‘sit’ during the ground contact phase of the stride. This action was characterized by a lower centre of mass, a greater forward lean in the trunk, and an incomplete extension of the hip joint at take-off. We conclude that sprinting on a dry sand surface may not be an appropriate method for training the maximum velocity phase in sprinting. Although this training method exerts a substantial overload on the athlete, as indicated by reductions in running velocity and stride length, it also induces detrimental changes to the athlete’s running technique which may transfer to competition sprinting.

Effect of curing time on selected properties of soil stabilized with fly ash, marble dust and waste sand for road sub-base materials.

Science.gov (United States)

Firat, Seyhan; Khatib, Jamal M; Yilmaz, Gulgun; Comert, A T

2017-07-01

The properties of sub-base filling materials in highway construction are essential, as they can determine the performance of the road in service. Normally, the existing materials are removed and replaced with new materials that have adequate load-bearing capacity. Rising environmental concern and new environmental legislations have made construction professionals consider other methods. These methods include stabilizing the existing materials with other additives to improve their performance. Additives can be waste materials generated by different industries. In this work, the existing excavated soil is stabilized with waste materials. The wastes consisted of fly ash, marble dust and waste sand. The percentage addition of waste materials was 5%, 10%, 15% and 20% (by mass) of the existing soil. The soil/waste specimens were cured for 1, 7, 28, 56, 90 and 112 days before testing. Testing included the dry unit weight and unconfined compressive strength ( q u ) as well as X-ray diffraction analysis and scanning electron microscopy observation. Also, the California Bearing Ratio values were obtained and are reported in this investigation. The results showed that the q u values increased with the increase in waste materials content. Also, there is tendency for the dry unit weight to increase with the increase in waste materials.

Prevalence of lameness among dairy cattle in Wisconsin as a function of housing type and stall surface.

Science.gov (United States)

Cook, Nigel B

2003-11-01

To determine the prevalence of lameness as a function of season (summer vs winter), housing type (free stalls vs tie stalls), and stall surface (sand vs any other surface) among lactating dairy cows in Wisconsin. Epidemiologic survey. 3,621 lactating dairy cows in 30 herds. Herds were visited once during the summer and once during the winter, and a locomotion score ranging from 1 (no gait abnormality) to 4 (severe lameness) was assigned to all lactating cows. Cows with a score of 3 or 4 were considered to be clinically lame. Mean +/- SD herd lameness prevalence was 21.1 +/- 10.5% during the summer and 23.9 +/- 10.7% during the winter; these values were significantly different. During the winter, mean prevalence of lameness in free-stall herds with non-sand stall surfaces (33.7%) was significantly higher than prevalences in free-stall herds with sand stall surfaces (21.2%), tie-stall herds with non-sand stall surfaces (21.7%), and tie-stall herds with sand stall surfaces (12.1%). Results suggest that the prevalence of lameness among dairy cattle in Wisconsin is higher than previously thought and that lameness prevalence is associated with season, housing type, and stall surface.

Jarosite added concrete along with fly ash: Properties and characteristics in fresh state

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Priyansha Mehra

2016-09-01

Full Text Available This paper presents the results of different properties and characteristics of jarosite added concrete along with fly ash during its fresh state. Jarosite is an industrial by product from zinc manufacturing industry obtained through hydrometallurgical process from its sulphide ore. It has been tried to incorporate jarosite in concrete as sand replacement. Different concrete mixtures have been prepared for three water–cement ratios (0.40, 0.45 and 0.50 and 5 jarosite replacement levels (0, 5, 10, 15, 20 and 25%. Cement has been partially replaced (25% by fly ash in all the concrete mixtures. Density, workability and setting & hardening of fresh concrete has been evaluated and analyzed. Keeping the environmental suitability of concrete in mind, toxicity leaching characteristic potential test has been performed on raw jarosite and concrete samples.

Aspects of the ecology of phlebotomine sand flies (Diptera: Psychodidae) in the Private Natural Heritage Reserve Sanctuary Caraça.

Science.gov (United States)

Tonelli, Gabriel Barbosa; Tanure, Aline; Rêgo, Felipe Dutra; Carvalho, Gustavo Mayr de Lima; Simões, Taynãna César; Andrade Filho, José Dilermando

2017-01-01

Leishmaniases are a set of parasitic diseases of zoonotic origin that are transmitted by sandfly vectors in wild, rural and urban environments. Their distribution is dependent not only the distribution of vectors, but also on the distribution of mammalian reservoirs. Only by understanding the transmission cycle of these diseases, such as knowing the participating vectors and reservoirs, can one can understand the epidemiology and ecological relationships of leishmaniases. Ecotourism has become an important area of economic growth in Brazil. One of the most visited tourist attractions in the state of Minas Gerais, the Reserva Particular do Patrimônio Natural Santuário do Caraça (RPPNSC) is located in the Quadrilátero Ferrífero. The aim of this study was to contribute to the control of leishmaniasis among tourists of the RPPNPC by surveying its sand fly fauna and testing for the presence of Leishmania DNA in females. Twenty-five CDC light traps were exposed on 7 trails of the RPPNPC where samples were collected bimonthly for a year, starting in June 2013. A total of 376 specimens of 18 species and 10 genera of sandflies were captured. The predominant species were Psychodopygus lloydi (72.34%) and Pintomyia monticola (5.59%). HaeIII restriction enzyme detected and characterized Leishmania braziliensis DNA in 2 of the samples for an infection rate of 0.7% (2/266). Recent studies found specimens of Ps. lloyd infected with Leishmania braziliensis elsewhere in Minas Gerais, which may be an indication that this species is involved in the transmission of Leishmania in this state.

Sand transportation and reverse patterns over leeward face of sand dune

Science.gov (United States)

Jiang, Hong; Dun, Hongchao; Tong, Ding; Huang, Ning

2017-04-01

Sand saltation has complex interactions with turbulent flow and dune form. Most models of wind-blown sand consider ideal circumstances such as steady wind velocity and a flat surface, and the bulk of data on wind flow and sand transport over an individual dune has focused mostly on the influence of dune shape or inter-dune space on the wind flow, neglecting the effect of morphology on sand saltation, particularly airflow and sand transportation over the leeward slope. Wind flow structures over the leeward slope of sand dunes have a fundamental influence on the organization of sand dunes. In order to understand sand dune dynamics, lee face airflow and sediment transportation should be paid more attention. Previous field observations could not measure turbulent flow structure well because of the limited observation points and the influence of experiment structure on wind field. In addition, the reverse sand particles over leeward face could not be collected by sand trap in field. Numerous field observations could not measure turbulent flow structure because of the limited observation points and the influence of experimental structures on the wind field. In addition, the reverse transport of sand particles over leeward face could not be collected by sand traps in field. Therefore, this paper aims to investigate the turbulent flow structure and sand transport pattern over the leeward slope. A numerical model of sand saltation over slope terrain is constructed, which also considers the coupling effects between air flow and sand particles. The large eddy simulation method is used to model turbulent flow. Sand transport is simulated by tracking the trajectory of each sand particle. The results show that terrain significantly alters the turbulent air flow structure and wind-blown sand movement, especially over the leeward slope. Here, mass flux increases initially and then decreases with height in the reversed flow region in the direction of wind flow, and the mass flux

Essays on the history of brazilian dipterology: III. Three remarkable notices from the 18th century, mainly related to myiasis-producing flies (Cochliomyia and Dermatobia

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Nelson Papavero

2012-12-01

Full Text Available This paper registers reports about dipterans made by three Portuguese who lived in Brazil during the 18th century. Luiz Gomes Ferreira, in his book "Erário mineral" ["Mineral revenue"], wrote curious passages related with myiasis-causing flies of the genus Cochliomyia. José Rodrigues de Mello registered, in Latin verses, the folklore for curing myiases caused by Cochliomyia hominivorax in cattle. Luiz dos Santos Vilhena, in the last of his twenty letters dealing with several aspects of life in Brazil, made reference to horseflies, human bot flies and mosquitos.

Survival and replication of Mycoplasma species in recycled bedding sand and association with mastitis on dairy farms in Utah.

Science.gov (United States)

Justice-Allen, A; Trujillo, J; Corbett, R; Harding, R; Goodell, G; Wilson, D

2010-01-01

Mycoplasma spp., usually Mycoplasma bovis, are important bovine pathogens that can cause mastitis, metritis, pneumonia, and arthritis. The currently documented routes of transmission of Mycoplasma spp. are through contaminated milking equipment and by direct animal contact. The existence of environmental sources for Mycoplasma spp. and their role in transmission and clinical disease is poorly characterized. Mycoplasma spp. (confirmed as M. bovis in 2 of 4 samples tested using PCR) was found in recycled bedding sand originating from a dairy experiencing an outbreak of clinical mycoplasma mastitis. Mycoplasma spp. were subsequently found in bedding sand from 2 other dairies whose bulk-tank milk was mycoplasma-positive. The association between the occurrence of Mycoplasma spp. in recycled bedding sand and mycoplasma mastitis in cows was further investigated using a pile of recycled sand from dairy 1. Study objectives included the determination of factors associated with the concentration of Mycoplasma spp. in recycled bedding sand and the duration of survival of mycoplasmas in the sand. We also evaluated the efficacy of 2 disinfectants at 2 different concentrations each for the elimination of Mycoplasma spp. from contaminated sand. Mycoplasma spp. survived in the sand pile for 8 mo. The concentration of Mycoplasma spp. within the sand pile was directly related to temperature and precipitation. It was also positively associated with the growth of gram-negative microorganisms, suggesting the possibility of the formation of a biofilm. Ideal temperatures for replication of Mycoplasma spp. occurred between 15 and 20 degrees C. Moisture in the sand and movement of the sand pile also appeared to play a role in replication of mycoplasmas. We found that 0.5% sodium hypochlorite or 2% chlorhexidine were efficacious in eliminating Mycoplasma spp. from contaminated bedding sand. Recycled bedding sand could be an environmental source of Mycoplasma spp., including M. bovis

Transcriptional profiling of cattle infected with Trypanosoma congolense highlights gene expression signatures underlying trypanotolerance and trypanosusceptibility

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Naessens Jan

2009-05-01

Full Text Available Abstract Background African animal trypanosomiasis (AAT caused by tsetse fly-transmitted protozoa of the genus Trypanosoma is a major constraint on livestock and agricultural production in Africa and is among the top ten global cattle diseases impacting on the poor. Here we show that a functional genomics approach can be used to identify temporal changes in host peripheral blood mononuclear cell (PBMC gene expression due to disease progression. We also show that major gene expression differences exist between cattle from trypanotolerant and trypanosusceptible breeds. Using bovine long oligonucleotide microarrays and real time quantitative reverse transcription PCR (qRT-PCR validation we analysed PBMC gene expression in naïve trypanotolerant and trypanosusceptible cattle experimentally challenged with Trypanosoma congolense across a 34-day infection time course. Results Trypanotolerant N'Dama cattle displayed a rapid and distinct transcriptional response to infection, with a ten-fold higher number of genes differentially expressed at day 14 post-infection compared to trypanosusceptible Boran cattle. These analyses identified coordinated temporal gene expression changes for both breeds in response to trypanosome infection. In addition, a panel of genes were identified that showed pronounced differences in gene expression between the two breeds, which may underlie the phenomena of trypanotolerance and trypanosusceptibility. Gene ontology (GO analysis demonstrate that the products of these genes may contribute to increased mitochondrial mRNA translational efficiency, a more pronounced B cell response, an elevated activation status and a heightened response to stress in trypanotolerant cattle. Conclusion This study has revealed an extensive and diverse range of cellular processes that are altered temporally in response to trypanosome infection in African cattle. Results indicate that the trypanotolerant N'Dama cattle respond more rapidly and with a

Chemical and environmental vector control as a contribution to the elimination of visceral leishmaniasis on the Indian subcontinent: cluster randomized controlled trials in Bangladesh, India and Nepal

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Das Pradeep

2009-10-01

not people shared their house with cattle. IRS was effective in all sites but LLINs were only effective in Bangladesh and India. Mud plastering did not reduce sand fly density (Bangladesh study; lime plastering in India and one Nepali site, resulted in a significant reduction of sand fly density but not in the second Nepali site. Conclusion Sand fly control can contribute to the regional VL elimination programme; IRS should be strengthened in India and Nepal but in Bangladesh, where vector control has largely been abandoned during the last decades, the insecticide treatment of existing bed nets (coverage above 90% in VL endemic districts could bring about an immediate reduction of vector populations; operational research to inform policy makers about the efficacious options for VL vector control and programme performance should be strengthened in the three countries.

Morphological description and DNA barcoding study of sand rice (Agriophyllum squarrosum, Chenopodiaceae) collected in Kazakhstan.

Science.gov (United States)

Genievskaya, Yuliya; Abugalieva, Saule; Zhubanysheva, Aibatsha; Turuspekov, Yerlan

2017-11-14

Sand rice (Agriophyllum squarrosum (L.) Moq.) is an annual shrub-like plant adapted to the mobile sand dunes in desert and semi-desert regions of Asia. It has a balanced nutrient composition with relatively high concentration of lipids and proteins, which results in its nutrition being similar to legumes. Sand rice's proteins contain the full range of essential amino acids. However, calories content is more similar to wheat. These features together with desert stress resistance make sand rice a potential food crop resilient to ongoing climate change. It is also an important fodder crop (on young stages of growth) for cattle in arid regions of Kazakhstan. In our work, sand rice samples were collected from two distant regions of Kazakhstan as a part of the nation-wide project to determine genetic variation of the native flora. Samples were collected in western and southeastern parts of Kazakhstan separated by distances of up to 1300 km. Sequences of the nuclear ribosomal DNA ITS1-5.8S-ITS2 region and the chloroplast matK gene confirmed the identity of species defined by morphological traits. Comparison with GenBank sequences revealed polymorphic sequence positions among Kazakh populations and GenBank references, and suggested a distinction among local populations of sand rice. The phylogenetic analysis of nucleotide sequences showed a clear partition of A. squarrosum (L.) Moq. from Agriophyllum minus Fisch. & C.A. Mey, which grows in the same sand dunes environment. DNA barcoding analyses of ITS and matK sequences showed a segregation of A. squarrosum from A. minus into separate clades in Maximum-Likelhood dendrograms. ITS analysis can be successfully used to characterize A. squarrosum populations growing quite distant from each other. The data obtained in this work provide the basis for further investigations on A. squarrosum population structure and may play a role in the screening of sand rice plants growing in desert and semi-desert environments of Central Asia

Comparative study of biogas from cattle dung and mixture of cattle ...

African Journals Online (AJOL)

This paper compares the rate of biogas production of cattle dung and a mixture of plantain peels with cattle dung. 18kg of cattle dung mixed with 36kg of water were charged to a digester while 9kg each of cattle dung and plantain peels mixed together with 36kg of water were charged to a separate digester. Both digesters ...

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.

Succession and Abundance of Staphylinidae in Cattle Dung in Uberlândia, Brazil

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Jorge Anderson Guimarães

1998-01-01

Full Text Available Fimicolous Staphylinidae prey on rearing dipterous in cattle dung, acting as their natural controllers, including pests such as horn fly. To survey the abundance and succession of these coleopterans in cattle dung deposited in pasture, six experiments were conducted from March to October 1995 in Uberlândia, State of Minas Gerais, Brazil. Cattle dung pats were exposed at a pasture for 1 hr, 8 hr, 24 hr, 2, 3, 7 and 10 days and were than taken to laboratory separate from each other, for Staphylinidae extraction. A total of 156 dung pats were exposed at pasture, from which 6225 Staphylinidae were recovered. Representing at least 30 species. Staphylinidae sp.1 (29.6%, Philonthus flavolimbatus (22.2%, Heterothops sp.1 (16.6%, Oxytelus sp.2 (7.6%, Aleochara sp.2 (7.6% and Criptobium sp.1 (4.4% were the most abundant, representing 87.8% from the total. The increased frequency of the majority of these species along the dung exposition time at pasture, indicated tha, they would be preying on at all the immature stages of the dipterous, or eggs and first instar larvae of species that lay eggs on the dung after its second exposition day at the pasture

Toxicity of geraniol solution in vitro to the poultry red mite, Dermanyssus gallinae

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George D.R.

2009-12-01

Full Text Available Geraniol is a bioactive component found in Palmarosa essential oil which has previously demonstrated good repellence to cattle ticks, mosquitoes and sand flies. The toxicity of geraniol to Dermanyssus gallinae, the most economically deleterious ectoparasite of laying hens in Europe, was studied in vitro in the laboratory. Exposure of D. gallinae to 0.5, 1 and 2% concentrations of geraniol (equating approximately to 0.02, 0.04 and 0.07 mg/cm2 geraniol, respectively over a period of 24 hours resulted in 100% mortality of D. gallinae at all doses used.

Radon exhalation of cementitious materials made with coal fly ash: Part 2 - testing hardened cement-fly ash pastes

International Nuclear Information System (INIS)

Kovler, K.; Perevalov, A.; Levit, A.; Steiner, V.; Metzger, L.A.

2005-01-01

Increased interest in measuring radionuclides and radon concentrations in fly ash (FA), cement and other components of building products is due to the concern about health hazards of naturally occurring radioactive materials (NORM). The paper focuses on studying the influence of FA on radon exhalation rate (radon flux) from cementitious materials. In the previous part of the paper the state of the art was presented, and the experiments for testing raw materials, Portland cement and coal fly ash, were described. Since the cement and FA have the most critical role in the radon release process relative to other concrete constituents (sand and gravel), and their contribution is dominant in the overall radium content of concrete, tests were carried out on cement paste specimens with different FA contents, 0-60% by weight of the binder (cement+FA). It is found that the dosage of FA in cement paste has a limited influence on radon exhalation rate, if the hardened material is relatively dense. The radon flux of cement-FA pastes is lower than that of pure cement paste: it is about ∼3 mBq m -2 s -1 for cement-FA pastes with FA content as high as 960 kg m -3

Investigation on Leaching Behaviour of Fly Ash and Bottom Ash Replacement in Self-Compacting Concrete

Science.gov (United States)

Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Bakri Abdullah, Mohd Mustafa Al

2016-06-01

Fly ash and bottom ash are some of the waste generated by coal-fired power plants, which contains large quantities of toxic and heavy metals. In recent years, many researchers have been interested in studying on the properties of self-compacting concrete incorporated with fly ash and bottom ash but there was very limited research from the combination of fly ash and bottom ash towards the environmental needs. Therefore, this research was focused on investigating the leachability of heavy metals of SCC incorporated with fly ash and bottom ash by using Toxicity Characteristic Leaching Procedure, Synthetic Precipitation Leaching Procedure and Static Leaching Test. The samples obtained from the coal-fired power plant located at Peninsula, Malaysia. In this study, the potential heavy metals leached out from SCC that is produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a substitute for sand with the ratios from 10% to 30% respectively were designated and cast. There are eight heavy metals of concern such as As, Cr, Pb, Zn, Cu, Ni, Mn and Fe. The results indicated that most of the heavy metals leached below the permissible limits from the United States Environmental Protection Agency and World Health Organization limit for drinking water. As a conclusion, the minimum leaching of the heavy metals from the incorporation of fly ash and bottom ash in self-compacting concrete was found in 20% of fly ash and 20% of bottom ash replacement. The results also indicate that this incorporation could minimize the potential of environmental problems.

Trypanosomosis: Potential driver of selection in African cattle

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Anamarija eSmetko

2015-04-01

Full Text Available Trypanosomosis is a serious cause of reduction in productivity of cattle in tsetse-fly infested areas. Baoule and other local Taurine cattle breeds in Burkina Faso are trypanotolerant. Zebuine cattle, which are also kept there are susceptible to trypanosomosis but bigger in body size. Farmers have continuously been intercrossing Baoule and Zebu animals to increase production and disease tolerance. The aim of this study was to compare levels of zebuine and taurine admixture in genomic regions potentially involved in trypanotolerance with background admixture of composites to identify differences in allelic frequencies of tolerant and non tolerant animals. The study was conducted on 214 animals (90 Baoule, 90 Zebu and 34 composites, genotyped with 25 microsatellites across the genome and with 155 SNPs in 23 candidate regions. Degrees of admixture of composites were analyzed for microsatellite and SNP data separately. Average Baoule admixture based on microsatellites across the genomes of the Baoule-Zebu composites was 0.31, which was smaller than the average Baoule admixture in the trypanosomosis candidate regions of 0.37 (P=0.15. Fixation index FST measured in the overall genome based on microsatellites or with SNPs from candidate regions indicates strong differentiation between breeds. Nine out of 23 regions had FST ≥ 0.20 calculated from haplotypes or individual SNPs. The levels of admixture were significantly different from background admixture, as revealed by microsatellite data, for six out of the nine regions. Five out of the six regions showed an excess of Baoule ancestry. Information about best levels of breed composition would be useful for future breeding activities, aiming at trypanotolerant animals with higher productive capacity.

Reclaimability of the spent sand mixture – sand with bentonite – sand with furfuryl resin

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J. Dańko

2011-04-01

Full Text Available Introduction of new binding materials and new technologies of their hardening in casting moulds and cores production requires theapplication of reclamation methods adequate to their properties as well as special devices realizing tasks. The spent sands circulationsystem containing the same kind of moulding and core sands is optimal from the point of view of the expected reclamation results.However, in the face of a significant variability of applied technologies and related to them various reclamation methods, the need - of theobtained reclamation products assessment on the grounds of systematic criteria and uniform bases – arises, with a tendency of indicatingwhich criteria are the most important for the given sand system. The reclaimability results of the mixture of the spent moulding sand withGeko S bentonite and the spent core sand with the Kaltharz 404U resin hardened by acidic hardener 100 T3, are presented in the paper.Investigations were performed with regard to the estimation of an influence of core sands additions (10 –25% on the reclaimed materialquality. Dusts and clay content in the reclaim, its chemical reaction (pH and ignition loss were estimated. The verification of the reclaiminstrumental assessment was performed on the basis of the technological properties estimation of moulding sand with bentonite, where the reclaimed material was used as a matrix.

Recent observations on the sand fly (Diptera: Psychodidae fauna of the State of Rondônia, Western Amazônia, Brazil: the importance of Psychdopygus davisi as a vector of zoonotic cutaneous leishmaniasis

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Gil Luis HS

2003-01-01

Full Text Available Sand flies were collected in the central region of the state of Rondônia (W 64º30' to 63º00' and S 10º00'to 11º00' using Shannon and CDC light traps from October 1997 to August 2000. A total of 85,850 specimens representing 78 named species were captured. Of these 14 were new records for Rondônia. The proportion of males/females was 1/1.131. Trypanosomatids, that are presently being identified, were detected in 11 species. Leishmania (Viannia naiffi was recorded from Psychodopygus davisi and P. hirsutus. In the present study the dominant species was P. davisi (39.6% followed by Lutzomyia whitmani (13.1%, P. carrerai (11.6%, and P. hirsutus (10.2%. The importance of P. davisi as a vector of zoonotic cutaneous leishmaniasis is discussed.

BIOGAS PRODUCTION IN DAIRY CATTLE SYSTEMS, USING BATCH DIGESTERS WITH AND WITHOUT SOLIDS SEPARATION IN THE SUBSTRATES

OpenAIRE

Anjos, Isis Dos; Toneli, Juliana T. C. L.; Sagula, Alex L.; Lucas Junior, Jorge de

2017-01-01

ABSTRACT This research aimed to evaluate the biogas production during the anaerobic biodigestion process of dairy cattle manure, with and without solids separation. Sixteen biodigesters of the batch type were used, each one with 2L of capacity, supplied with manure in four different conditions: (1) pure manure, after washing the floors of the free stall system; (2) manure after the solids separator; (3) manure after the solids separator and sand decanter and (4) manure with the solid retained...

Clinical and pathological study of an outbreak of obstructive urolithiasis in feedlot cattle in southern Brazil

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Loretti Alexandre Paulino

2003-01-01

Full Text Available The epidemiology, clinical picture and pathology of an outbreak of urolithiasis in cattle in southern Brazil are described. The disease occurred in August 1999 in a feedlot beef cattle herd. Five out of 1,100 castrated steers were affected. Clinical signs included colic and ventral abdominal distension. White, sand-grain-like mineral deposits precipitated on the preputial hairs. Affected cattle died spontaneously 24-48 hrs after the onset of the clinical signs. Only one animal recovered after perineal urethrostomy. Necropsy findings included calculi blocking the urethral lumen of the distal portion of the penile sigmoid flexure, urinary bladder rupture with leakage of urine into the abdominal cavity and secondary fibrinous peritonitis. Daily water intake was low since water sources were scarce and not readily available. The animals were fed rations high in grains and received limited amounts of roughage. Biochemical analysis revealed that the calculi were composed of ammonium phosphate. A calcium-phosphorus imbalance (0.4:0.6 was detected in the feedlot ration. For the outbreak, it is suggested that contributing factors to urolith formation include insufficient fiber ingestion, low water intake and high dietary levels of phosphorus. No additional cases were observed in that feedlot after preventive measures were established. Similar dietary mismanagement in fattening steers has been associated with obstructive urolithiasis in feedlot beef cattle in other countries.

Aspects of the ecology of phlebotomine sand flies (Diptera: Psychodidae in the Private Natural Heritage Reserve Sanctuary Caraça.

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Gabriel Barbosa Tonelli

Full Text Available Leishmaniases are a set of parasitic diseases of zoonotic origin that are transmitted by sandfly vectors in wild, rural and urban environments. Their distribution is dependent not only the distribution of vectors, but also on the distribution of mammalian reservoirs. Only by understanding the transmission cycle of these diseases, such as knowing the participating vectors and reservoirs, can one can understand the epidemiology and ecological relationships of leishmaniases. Ecotourism has become an important area of economic growth in Brazil. One of the most visited tourist attractions in the state of Minas Gerais, the Reserva Particular do Patrimônio Natural Santuário do Caraça (RPPNSC is located in the Quadrilátero Ferrífero. The aim of this study was to contribute to the control of leishmaniasis among tourists of the RPPNPC by surveying its sand fly fauna and testing for the presence of Leishmania DNA in females. Twenty-five CDC light traps were exposed on 7 trails of the RPPNPC where samples were collected bimonthly for a year, starting in June 2013. A total of 376 specimens of 18 species and 10 genera of sandflies were captured. The predominant species were Psychodopygus lloydi (72.34% and Pintomyia monticola (5.59%. HaeIII restriction enzyme detected and characterized Leishmania braziliensis DNA in 2 of the samples for an infection rate of 0.7% (2/266. Recent studies found specimens of Ps. lloyd infected with Leishmania braziliensis elsewhere in Minas Gerais, which may be an indication that this species is involved in the transmission of Leishmania in this state.

Breeds of cattle

NARCIS (Netherlands)

Buchanan, David S.; Lenstra, Johannes A.

2015-01-01

This chapter gives an overview on the different breeds of cattle (Bos taurus and B. indicus). Cattle breeds are presented and categorized according to utility and mode of origin. Classification and phylogeny of breeds are also discussed. Furthermore, a description of cattle breeds is provided.

Eastern Scheldt Sand, Baskarp Sand No. 15

DEFF Research Database (Denmark)

Andersen, A. T; Madsen, E. B.; Schaarup-Jensen, A. L.

The present data report contains data from 13 drained triaxial tests, performed on two different sand types in the Soil Mechanics Laboratory at Aalborg University in March, 1997. Two tests have been performed on Baskarp Sand No. 15, which has already ken extensively tested in the Soil Mechanics...... Laboratory. The remaining 11 triaxial tests have ben performed on Eastern Scheldt Sand, which is a material not yet investigated at the Soil Mechanics Laboratory. In the first pari of this data report, the characteristics of the two sand types in question will be presented. Next, a description...... will described. In this connection, the procedure for preparation of the soil specimens will be presented, and the actual performance of the tests will be briefly outlined. Finally, the procedure for processing of the measurements from the laboratory in order to obtain usable data will be described. The final...

Diversity of sand flies in domiciliary environment of Santarém, state of Pará, Brazil: species composition and abundance patterns in rural and urban areas Diversidade de flebotomíneos no ambiente domiciliar de Santarém, estado do Pará, Brazil: composição de espécies e padrões de abundância em áreas urbanas e rurais

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Marlisson Augusto Costa Feitosa

2012-01-01

Full Text Available This paper aimed to evaluate the richness, abundance and frequency of sand fly occurrence in rural and urban areas American visceral Leishmaniasis -AVL is endemic in the study area of Santarém municipality, Pará state. Sand flies were collected during 1995-2000, using CDC light traps placed in neighborhoods and rural areas of the municipality. A total of 53.454 individuals and 26 species of sand flies were collected. The most abundant species in both urban and rural environments was Lutzomyia longipalpis, vector of AVL in the area. The highest species richness by capture was in rural area. In all years sampled, the largest number of species of sand fly collected was always in rural areas. The species of sand flies in urban and rural area were similar in 11 species. In the rural area other 11 species were found, a total of 22 species. Shannon-Wiener index ranged from 0.12 to 0.84 at rural areas and 0.08 to 0.34 at urban ones. In general, rural localities showed higher diversity (H' of phlebotomines than urban ones. Individual-based rarefaction curves for each area demonstrated that urban localities had the lowest expected number of phlebotomine species and the richest rural ones reach higher expected values with lower amount of individuals than urban sites. The most frequent species were Lutzomyia longipalpis, Evandromyia carmelinoi and Bichromomyia flaviscutellata.Com o objetivo de comparar a riqueza, abundância e freqüência de ocorrência de flebotomíneos em sítios rurais e urbanos numa área endêmica de leishmaniose visceral no município de Santarém (PA foi realizado no período entre 1995-2000, capturas de flebotomíneos por meio de armadilhas luminosas CDC montadas no ambiente domiciliar em diferentes bairros e localidades rurais do município. Foram capturados 53.454 indivíduos, de 26 espécies e dentre elas, a mais abundante, tanto em ambiente urbano e rural, foi Lutzomyia longipalpis, vetor da leishmaniose visceral americana na

Cholistan and Cholistani Breed of Cattle

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U. Farooq, H. A. Samad*, F. Sher1, M. Asim1 and M. Arif Khan2

2010-04-01

Full Text Available Cholistan, once a green and prosperous land with the source of water being the ancient Hakra River, was also the cradle of great Hakra Valley Civilization. It is sprawled at an area of 26,000 Km2, located between the latitudes 27º42´and 29º45´North and longitudes 69º52´and 75º24´East. The bioclimatic system of Cholistan falls under the category of “tropical desert” with very scanty rainfall. Geomorphologically, the soils of Cholistan are a complex blend of river alluvium and Aeolin sands. Based on topography, type of soil and vegetation, this desert is divided into two geomorphic regions: the Lesser Cholistan (the Northern 7,770 Km² region and the Greater Cholistan (the Southern 18,130 Km² region. The primary source of water is rainfall which is utilized through natural depressions or man-made ponds called “Tobas” and “Dahars.” The secondary source is underground water which is brackish and salty and not fit for human/animal consumption. Two livestock production systems prevail under pastoralism in Cholistan viz. transhumanie and nomadic. Despite an uncertain, unpredictable rainfall, low humidity and extremes in temperatures, Cholistan has long been famous for raising different breeds of livestock, contributing a significant share to national milk, meat and wool output. The total livestock population estimated during 2006 was 12,09528, out of which 47% were cattle. Cholistani cattle are considered to be ancestor of the Sahiwal and are a thermo-tolerant, tick-resistant breed. Preliminary data on some productive and reproductive traits of Cholistani cows maintained at Govt. Livestock Station, Jugait Peer, Bahawalpur during the period 2005 to 2009 revealed the avergae values for the productive traits i.e. lactation length, lactation yield, dry period, service period and fat percentage in milk as 165 days, 1235 liters, 155 days, 121 days and 4.8%, respectively. Similarly, the average values for reproductive traits i.e. age at

The Agersoe cattle

DEFF Research Database (Denmark)

Withen, K.B.; Brüniche-Olsen, A.; Pedersen, Bo Vest

2011-01-01

A phenotypically interesting strain of cattle existed on the small island of Agersoe, on the west coast of Zealand, Denmark, in the beginning of the last decade. The cattle share a great resemblance to the extinct Danish breed, the Island cattle. The objective of this study was to genetically...

Cattle genomics and its implications for future nutritional strategies for dairy cattle.

Science.gov (United States)

Seo, S; Larkin, D M; Loor, J J

2013-03-01

The recently sequenced cattle (Bos taurus) genome unraveled the unique genomic features of the species and provided the molecular basis for applying a systemic approach to systematically link genomic information to metabolic traits. Comparative analysis has identified a variety of evolutionary adaptive features in the cattle genome, such as an expansion of the gene families related to the rumen function, large number of chromosomal rearrangements affecting regulation of genes for lactation, and chromosomal rearrangements that are associated with segmental duplications and copy number variations. Metabolic reconstruction of the cattle genome has revealed that core metabolic pathways are highly conserved among mammals although five metabolic genes are deleted or highly diverged and seven metabolic genes are present in duplicate in the cattle genome compared to their human counter parts. The evolutionary loss and gain of metabolic genes in the cattle genome may reflect metabolic adaptations of cattle. Metabolic reconstruction also provides a platform for better understanding of metabolic regulation in cattle and ruminants. A substantial body of transcriptomics data from dairy and beef cattle under different nutritional management and across different stages of growth and lactation are already available and will aid in linking the genome with metabolism and nutritional physiology of cattle. Application of cattle genomics has great potential for future development of nutritional strategies to improve efficiency and sustainability of beef and milk production. One of the biggest challenges is to integrate genomic and phenotypic data and interpret them in a biological and practical platform. Systems biology, a holistic and systemic approach, will be very useful in overcoming this challenge.

Study of Experiment on Rock-like Material Consist of fly-ash, Cement and Mortar

Science.gov (United States)

Nan, Qin; Hongwei, Wang; Yongyan, Wang

2018-03-01

Study the uniaxial compression test of rock-like material consist of coal ash, cement and mortar by changing the sand cement ratio, replace of fine coal, grain diameter, water-binder ratio and height-diameter ratio. We get the law of four factors above to rock-like material’s uniaxial compression characteristics and the quantitative relation. The effect law can be sum up as below: sample’s uniaxial compressive strength and elasticity modulus tend to decrease with the increase of sand cement ratio, replace of fine coal and water-binder ratio, and it satisfies with power function relation. With high ratio increases gradually, the uniaxial compressive strength and elastic modulus is lower, and presents the inverse function curve; Specimen tensile strength decreases gradually with the increase of fly ash. By contrast, uniaxial compression failure phenomenon is consistent with the real rock common failure pattern.

Study of trypanosome and anaemia indicators during the eradication of tsetse flies from Unguja island, United Republic of Tanzania

International Nuclear Information System (INIS)

Dwinger, R.H.; Holland, W.G.; Ndegwa, T.K.; Wint, W.; Kassim, S.S.; Hongjie, P.; Slingenbergh, J.H.W.

2000-01-01

A large number of cattle has been monitored regularly during a ten-year period on Unguja island, United Republic of Tanzania, as part of a number of consecutive programmes to initially control and eventually eradicate tsetse and trypanosomosis. Haematological and parasitological results were used among others to monitor and adjust the control and eradication programmes from 1988 to 1997. A Geographic Information System (GIS) was applied to the data set to assess changes of animal health parameters in time and space. Analysis of the data showed significant changes over the years in infection status and degree of anaemia. Moreover, differences in health status of cattle populations between adjacent geographic areas were detected. Regular monitoring using standardized protocols by a multidisciplinary team resulted eventually in the eradication of tsetse flies from the island. (author)

Submarine sand ridges and sand waves in the eastern part of the China Sea

Science.gov (United States)

Wu, Ziyin; Li, Shoujun; Shang, Jihong; Zhou, Jieqiong; Zhao, Dineng; Liang, Yuyang

2016-04-01

Integrated with multi-beam and single-beam echo sounding data, as well as historical bathymetric data, submarine bathymetric maps of the eastern part of the China Sea, including the Bohai Sea, Huanghai Sea, and East China Sea, are constructed to systematically study submarine sand ridges and sand waves in the eastern part of the China Sea, combined with high-resolution seismic, sub-bottom profile and borehole data. Submarine sand ridges are extraordinarily developed in the eastern part of the China Sea, and 7 sand ridge areas can be divided from north to south, that is, the Laotieshan Channel sand ridge area in the Bohai Sea, the Korea Bay sand ridge area in the southern Huanghai Sea, the sand ridge area in the eastern Huanghai islands and the Huanghai Troughs, the Jianggang sand ridge area in the western Huanghai Sea, the sand ridge area in the East China Sea shelf, and the sand ridge and sand wave area in the Taiwan Strait and Taiwan Banks. The distribution area of the sand ridges and sand waves covers more than 450,000 km2, wherein ~10,000 km2 in the Bohai Bay, ~200,000 km2 in the Huanghai Sea, ~200,000 km2 in the East China Sea shelf, and ~40,000 km2 in the Taiwan Strait and Taiwan Banks, respectively. The great mass of sand ridges are distributed within water depth of 5-160 m, with a total length of over 160 km and a main width of 5-10 km. The inner structure of the sand ridges presents features of high-angle inclined beddings, with main lithology of sands, sand-mud alternations partly visible, and a small number of mud cores. Dating results indicate that the sand ridges in the eastern part of the China Sea are mainly developed in the Holocene. Sea-level variation dominates the sand ridge evolution in the eastern part of the China Sea since the LGM, and the sand ridges developed in the area of < 60m water depth are appeared in bad activity, meanwhile sand ridges with good activity are still developed in large scale.

Molecular Epidemiology for Vector Research on Leishmaniasis

Science.gov (United States)

Kato, Hirotomo; Gomez, Eduardo A; Cáceres, Abraham G; Uezato, Hiroshi; Mimori, Tatsuyuki; Hashiguchi, Yoshihisa

2010-01-01

Leishmaniasis is a protozoan disease caused by the genus Leishmania transmitted by female phlebotomine sand flies. Surveillance of the prevalence of Leishmania and responsive vector species in endemic and surrounding areas is important for predicting the risk and expansion of the disease. Molecular biological methods are now widely applied to epidemiological studies of infectious diseases including leishmaniasis. These techniques are used to detect natural infections of sand fly vectors with Leishmania protozoa and are becoming powerful tools due to their sensitivity and specificity. Recently, genetic analyses have been performed on sand fly species and genotyping using PCR-RFLP has been applied to the sand fly taxonomy. In addition, a molecular mass screening method has been established that enables both sand fly species and natural leishmanial infections to be identified simultaneously in hundreds of sand flies with limited effort. This paper reviews recent advances in the study of sand flies, vectors of leishmaniasis, using molecular biological approaches. PMID:20617005

Molecular Epidemiology for Vector Research on Leishmaniasis

Directory of Open Access Journals (Sweden)

Hirotomo Kato

2010-03-01

Full Text Available Leishmaniasis is a protozoan disease caused by the genus Leishmania transmitted by female phlebotomine sand flies. Surveillance of the prevalence of Leishmania and responsive vector species in endemic and surrounding areas is important for predicting the risk and expansion of the disease. Molecular biological methods are now widely applied to epidemiological studies of infectious diseases including leishmaniasis. These techniques are used to detect natural infections of sand fly vectors with Leishmania protozoa and are becoming powerful tools due to their sensitivity and specificity. Recently, genetic analyses have been performed on sand fly species and genotyping using PCR-RFLP has been applied to the sand fly taxonomy. In addition, a molecular mass screening method has been established that enables both sand fly species and natural leishmanial infections to be identified simultaneously in hundreds of sand flies with limited effort. This paper reviews recent advances in the study of sand flies, vectors of leishmaniasis, using molecular biological approaches.

Molecular epidemiology for vector research on leishmaniasis.

Science.gov (United States)

Kato, Hirotomo; Gomez, Eduardo A; Cáceres, Abraham G; Uezato, Hiroshi; Mimori, Tatsuyuki; Hashiguchi, Yoshihisa

2010-03-01

Leishmaniasis is a protozoan disease caused by the genus Leishmania transmitted by female phlebotomine sand flies. Surveillance of the prevalence of Leishmania and responsive vector species in endemic and surrounding areas is important for predicting the risk and expansion of the disease. Molecular biological methods are now widely applied to epidemiological studies of infectious diseases including leishmaniasis. These techniques are used to detect natural infections of sand fly vectors with Leishmania protozoa and are becoming powerful tools due to their sensitivity and specificity. Recently, genetic analyses have been performed on sand fly species and genotyping using PCR-RFLP has been applied to the sand fly taxonomy. In addition, a molecular mass screening method has been established that enables both sand fly species and natural leishmanial infections to be identified simultaneously in hundreds of sand flies with limited effort. This paper reviews recent advances in the study of sand flies, vectors of leishmaniasis, using molecular biological approaches.

Fontainebleau Sand

DEFF Research Database (Denmark)

Leth, Caspar Thrane

2006-01-01

The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand.......The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand....

Assessment of contamination by percolation of septic tank effluent through natural and amended soils.

Science.gov (United States)

Cheung, K C; Venkitachalam, T H

2004-01-01

Fly ash has been found to be a potential material for the treatment of municipal and industrial wastewater, and may be useful in the treatment of septic tank effluent. Laboratory columns (30 cm) were used to determine the sorption capacity and hydraulic properties of lagoon fly ash, loamy sand, sand, and sand amended by lagoon fly ash (30 and 60%) and red mud gypsum (20%). The removal of chemical oxygen demand (COD) was high in all column effluents (71-93%). Extent of nitrification was high in Spearwood sand, Merribrook loamy sand and 20% red mud gypsum amended Spearwood sand. However, actual removal of nitrogen (N) was high in columns containing lagoon fly ash. Unamended Spearwood sand possessed only minimal capacity for P sorption. Merribrook loamy sand and red mud gypsum amended sand affected complete P removal throughout the study period of 12 weeks. Significant P leakage occurred from lagoon fly ash amended sand columns following 6-10 weeks of operation. Neither lagoon fly ash nor red mud gypsum caused any studied heavy metal contamination including manganese (Mn), lead (Pb), zinc (Zn), cadmium (Cd) and chromium (Cr) of effluent. It can be concluded that Merribrook loamy sand is better natural soil than Spearwood sand as a filter medium. The addition of lagoon fly ash enhanced the removal of P in Spearwood sand but the efficiency was lower than with red mud gypsum amendment.

Development of UHPC Mixtures Utilizing Natural and Industrial Waste Materials as Partial Replacements of Silica Fume and Sand

OpenAIRE

Ahmad, Shamsad; Hakeem, Ibrahim; Maslehuddin, Mohammed

2014-01-01

In the exploratory study presented in this paper, an attempt was made to develop different mixtures of ultrahigh performance concrete (UHPC) using various locally available natural and industrial waste materials as partial replacements of silica fume and sand. Materials such as natural pozzolana (NP), fly ash (FA), limestone powder (LSP), cement kiln dust (CKD), and pulverized steel slag (PSS), all of which are abundantly available in Saudi Arabia at little or no cost, were employed in the de...

Study of Black Sand Particles from Sand Dunes in Badr, Saudi Arabia Using Electron Microscopy

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Haider Abbas Khwaja

2015-08-01

Full Text Available Particulate air pollution is a health concern. This study determines the microscopic make-up of different varieties of sand particles collected at a sand dune site in Badr, Saudi Arabia in 2012. Three categories of sand were studied: black sand, white sand, and volcanic sand. The study used multiple high resolution electron microscopies to study the morphologies, emission source types, size, and elemental composition of the particles, and to evaluate the presence of surface “coatings or contaminants” deposited or transported by the black sand particles. White sand was comprised of natural coarse particles linked to wind-blown releases from crustal surfaces, weathering of igneous/metamorphic rock sources, and volcanic activities. Black sand particles exhibited different morphologies and microstructures (surface roughness compared with the white sand and volcanic sand. Morphological Scanning Electron Microscopy (SEM and Laser Scanning Microscopy (LSM analyses revealed that the black sand contained fine and ultrafine particles (50 to 500 nm ranges and was strongly magnetic, indicating the mineral magnetite or elemental iron. Aqueous extracts of black sands were acidic (pH = 5.0. Fe, C, O, Ti, Si, V, and S dominated the composition of black sand. Results suggest that carbon and other contaminant fine particles were produced by fossil-fuel combustion and industrial emissions in heavily industrialized areas of Haifa and Yanbu, and transported as cloud condensation nuclei to Douf Mountain. The suite of techniques used in this study has yielded an in-depth characterization of sand particles. Such information will be needed in future environmental, toxicological, epidemiological, and source apportionment studies.

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

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.

Current Methods to Detoxify Fly Ash from Waste Incineration

Energy Technology Data Exchange (ETDEWEB)

Hallgren, Christine; Stroemberg, Birgitta [TPS Termiska Processer AB, Nykoeping (Sweden)

2004-07-01

Fly ash from waste incineration contains large amounts of heavy metals and dioxins, which will cause a significant disposal problem within the coming years. The amount of fly ash produced in Sweden is currently approximately 60,000 tons/y. New technological options for the decontamination and/or inertization of incinerator fly ash are being developed with the objective of rendering a product that can be reused or, at least, be deposited at standard landfill sites with no risk. Many of these technologies have been tested at industrial scale or in pilot projects. The proposed alternatives include: Thermal treatments; Immobilization/stabilization by cement based techniques; Wet chemical treatments (extractions, immobilizations); Microbiological treatments. Of these, thermal treatments are the most promising solution. Depending on the temperature thermal treatments are classified in two main types: 1) low temperature (below 600 deg C) thermal treatments and 2) high temperature (above 1200 deg C) thermal treatments (vitrification). Most dioxins can be successfully destroyed at temperatures up to 400 deg C under oxygen deficient conditions and at temperatures up to 600 deg C under oxidising conditions. However most heavy metals remain in the fly ash after low temperature treatment. At a temperature of 900 deg C most heavy metals can also be removed in a 10% HCl atmosphere by forming volatile metal chlorides (CT-Fluapur process). During vitrification processes the fly ash melts and forms an inert glassy slag. The product does not leach any significant amount of heavy metals and is free from dioxin. The volume of the fly ash is significantly reduced. The product can be land filled at low costs or used as construction material. The properties of the product depend on the cooling process and on additives such as sand, limestone or waste glass. A series of vitrification methods at industrial size or in pilot scale using different furnaces are studied. Among these, plasma

New generation expandable sand screens

OpenAIRE

Syltøy, Christer

2014-01-01

Master's thesis in Petroleum engineering This thesis aims to give a general insight into sand control and various sorts of sand control measures and applications of sand control tools. Special focus will be given to expandable sand screens – a technology which came about in the late 1990’s through the use of flexible, expandable tubulars as base pipe in sand screens. More specifically Darcy’s Hydraulic Endurance Screens, a compliant sand screen system using hydraulic activation, and the fu...

Saltation of non-spherical sand particles.

Directory of Open Access Journals (Sweden)

Zhengshi Wang

Full Text Available Saltation is an important geological process and the primary source of atmospheric mineral dust aerosols. Unfortunately, no studies to date have been able to precisely reproduce the saltation process because of the simplified theoretical models used. For example, sand particles in most of the existing wind sand movement models are considered to be spherical, the effects of the sand shape on the structure of the wind sand flow are rarely studied, and the effect of mid-air collision is usually neglected. In fact, sand grains are rarely round in natural environments. In this paper, we first analyzed the drag coefficients, drag forces, and starting friction wind speeds of sand grains with different shapes in the saltation process, then established a sand saltation model that considers the coupling effect between wind and the sand grains, the effect of the mid-air collision of sand grains, and the effect of the sand grain shape. Based on this model, the saltation process and sand transport rate of non-spherical sand particles were simulated. The results show that the sand shape has a significant impact on the saltation process; for the same wind speed, the sand transport rates varied for different shapes of sand grains by as much as several-fold. Therefore, sand shape is one of the important factors affecting wind-sand movement.

Vitamin C Nutrition in Cattle

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T. Matsui

2012-05-01

Full Text Available Domestic animals, including ruminants, can synthesize vitamin C (VC in their liver; as such, the dietary requirement for VC has not been confirmed in these animals. The adequacy of VC has been evaluated by quantifying VC levels in plasma, but the reported values in bovine plasma have been widely variable. Plasma VC concentration is decreased by heat stress, hepatic lesions, fattening, and infectious diseases such as mastitis in cattle. Therefore, VC supplementation is potentially beneficial for cattle with low plasma VC concentration. This review discusses the methods for determination of plasma VC concentration in cattle, VC nutrition, and the efficacy of VC supplementation in calves, dairy cattle, and beef cattle. Additionally I propose a reference range for plasma VC concentration in Japanese Black cattle.

Vitamin C nutrition in cattle.

Science.gov (United States)

Matsui, T

2012-05-01

Domestic animals, including ruminants, can synthesize vitamin C (VC) in their liver; as such, the dietary requirement for VC has not been confirmed in these animals. The adequacy of VC has been evaluated by quantifying VC levels in plasma, but the reported values in bovine plasma have been widely variable. Plasma VC concentration is decreased by heat stress, hepatic lesions, fattening, and infectious diseases such as mastitis in cattle. Therefore, VC supplementation is potentially beneficial for cattle with low plasma VC concentration. This review discusses the methods for determination of plasma VC concentration in cattle, VC nutrition, and the efficacy of VC supplementation in calves, dairy cattle, and beef cattle. Additionally I propose a reference range for plasma VC concentration in Japanese Black cattle.

The Sand Fly Salivary Protein Lufaxin Inhibits the Early Steps of the Alternative Pathway of Complement by Direct Binding to the Proconvertase C3b-B

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Antonio F. Mendes-Sousa

2017-08-01

Full Text Available Saliva of the blood feeding sand fly Lutzomyia longipalpis was previously shown to inhibit the alternative pathway (AP of the complement system. Here, we have identified Lufaxin, a protein component in saliva, as the inhibitor of the AP. Lufaxin inhibited the deposition of C3b, Bb, Properdin, C5b, and C9b on agarose-coated plates in a dose-dependent manner. It also inhibited the activation of factor B in normal serum, but had no effect on the components of the membrane attack complex. Surface plasmon resonance (SPR experiments demonstrated that Lufaxin stabilizes the C3b-B proconvertase complex when passed over a C3b surface in combination with factor B. Lufaxin was also shown to inhibit the activation of factor B by factor D in a reconstituted C3b-B, but did not inhibit the activation of C3 by reconstituted C3b-Bb. Proconvertase stabilization does not require the presence of divalent cations, but addition of Ni2+ increases the stability of complexes formed on SPR surfaces. Stabilization of the C3b-B complex to prevent C3 convertase formation (C3b-Bb formation is a novel mechanism that differs from previously described strategies used by other organisms to inhibit the AP of the host complement system.

The Sand Fly Salivary Protein Lufaxin Inhibits the Early Steps of the Alternative Pathway of Complement by Direct Binding to the Proconvertase C3b-B.

Science.gov (United States)

Mendes-Sousa, Antonio F; do Vale, Vladimir Fazito; Silva, Naylene C S; Guimaraes-Costa, Anderson B; Pereira, Marcos H; Sant'Anna, Mauricio R V; Oliveira, Fabiano; Kamhawi, Shaden; Ribeiro, José M C; Andersen, John F; Valenzuela, Jesus G; Araujo, Ricardo N

2017-01-01

Saliva of the blood feeding sand fly Lutzomyia longipalpis was previously shown to inhibit the alternative pathway (AP) of the complement system. Here, we have identified Lufaxin, a protein component in saliva, as the inhibitor of the AP. Lufaxin inhibited the deposition of C3b, Bb, Properdin, C5b, and C9b on agarose-coated plates in a dose-dependent manner. It also inhibited the activation of factor B in normal serum, but had no effect on the components of the membrane attack complex. Surface plasmon resonance (SPR) experiments demonstrated that Lufaxin stabilizes the C3b-B proconvertase complex when passed over a C3b surface in combination with factor B. Lufaxin was also shown to inhibit the activation of factor B by factor D in a reconstituted C3b-B, but did not inhibit the activation of C3 by reconstituted C3b-Bb. Proconvertase stabilization does not require the presence of divalent cations, but addition of Ni 2+ increases the stability of complexes formed on SPR surfaces. Stabilization of the C3b-B complex to prevent C3 convertase formation (C3b-Bb formation) is a novel mechanism that differs from previously described strategies used by other organisms to inhibit the AP of the host complement system.

The Sand Fly Salivary Protein Lufaxin Inhibits the Early Steps of the Alternative Pathway of Complement by Direct Binding to the Proconvertase C3b-B

Science.gov (United States)

Mendes-Sousa, Antonio F.; do Vale, Vladimir Fazito; Silva, Naylene C. S.; Guimaraes-Costa, Anderson B.; Pereira, Marcos H.; Sant’Anna, Mauricio R. V.; Oliveira, Fabiano; Kamhawi, Shaden; Ribeiro, José M. C.; Andersen, John F.; Valenzuela, Jesus G.; Araujo, Ricardo N.

2017-01-01

Saliva of the blood feeding sand fly Lutzomyia longipalpis was previously shown to inhibit the alternative pathway (AP) of the complement system. Here, we have identified Lufaxin, a protein component in saliva, as the inhibitor of the AP. Lufaxin inhibited the deposition of C3b, Bb, Properdin, C5b, and C9b on agarose-coated plates in a dose-dependent manner. It also inhibited the activation of factor B in normal serum, but had no effect on the components of the membrane attack complex. Surface plasmon resonance (SPR) experiments demonstrated that Lufaxin stabilizes the C3b-B proconvertase complex when passed over a C3b surface in combination with factor B. Lufaxin was also shown to inhibit the activation of factor B by factor D in a reconstituted C3b-B, but did not inhibit the activation of C3 by reconstituted C3b-Bb. Proconvertase stabilization does not require the presence of divalent cations, but addition of Ni2+ increases the stability of complexes formed on SPR surfaces. Stabilization of the C3b-B complex to prevent C3 convertase formation (C3b-Bb formation) is a novel mechanism that differs from previously described strategies used by other organisms to inhibit the AP of the host complement system. PMID:28912782

Improvement of indigenous cattle to modern Japanese Black (Wagyu) cattle

Science.gov (United States)

Oikawa, T.

2018-02-01

Wagyu cattle have been improved from indigenous cattle raised in Japan since the country was opened 100 years ago. Characteristics of the breed were formed during that period. Here, the process of the breeding is described, and recent topics about breeding studies are discussed.

Processed bottom ash for replacing fine aggregate in making high-volume fly ash concrete

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Antoni

2017-01-01

Full Text Available Bottom ash is a coal plant by-product that is abundant and underutilized. There is the potential use of bottom ash as a fine aggregate replacement in concrete mixtures; however, the problems of water absorption and uniformity of quality of the material need to be overcome first. In this study, bottom ash was treated by sieve separation and pounding to smaller particle size for use as a sand substitute. The physical and chemical characteristics of bottom ash were tested after treatment including water absorption, sieve analysis, and fineness modulus. Highvolume fly ash (HVFA mortar specimens were made and the compressive strength and flowability test using bottom ash after treatment are compared with that of the sand specimen. Low water to cementitious ratio was used to ensure higher strength from the cementitious paste and superplasticizer demand was determined for each treatment. The result showed that bottom ash can be used as fine aggregate replacement material. Sieve separation of the bottom ash could produce 75% of the compressive strength compared with the control sand specimen, whereas pounded bottom ash could have up to 96% of the compressive strength of the control specimen. A 28-day compressive strength of 45 MPa was achievable with 100% replacement of fine aggregate with bottom ash.

Lutzomyia (Helcocyrtomyia) Apache Young and Perkins (Diptera: Psychodidae) feeds on reptiles

Science.gov (United States)

Phlebotomine sand flies are vectors of bacteria, parasites, and viruses. In the western USA a sand fly, Lutzomyia apache Young and Perkins, was initially associated with epizootics of vesicular stomatitis virus (VSV), because sand flies were trapped at sites of an outbreak. Additional studies indica...

Cementing Efficiency of Low Calcium Fly Ash in Fly Ash Concretes

OpenAIRE

T. D. Gunneswara Rao; Mudimby Andal

2014-01-01

Research on the utilization of fly ash will no longer refer the fly ash as a waste material of thermal power plants. Use of fly ash in concrete making, makes the concrete economical as well as durable. The fly ash is being added to the concrete in three ways namely, as partial replacement to cement, as partial replacement to fine aggregates and as admixture. Addition of fly ash to the concrete in any one of the form mentioned above, makes the concrete more workable and durable than the conven...

Trace element toxicity in VA mycorrhizal cucumber grown on weathered coal fly ash

Energy Technology Data Exchange (ETDEWEB)

Dosskey, M.G.; Adriano, D.C. (University of Georgia, Aiken, SC (United States). Savannah River Ecology Lab.)

1993-11-01

Mycorrhizal colonization is widely recognized as enhancing plant growth on severely disturbed sites. A greenhouse pot experiment was conducted to determine if inoculation with vesicular-arbuscular mycorrhizal (VAM) fungi will enhance vegetation establishment on abandoned coal fly ash basinss, Spores of Glomus intraradices (Schenck and Smith) and Glomus etunicatum (Becker and Gerdemann) were added to weathered precipitator ash (EC-0.91 dSm[sup -1], pH 5.0) and to a pasteurized soils of the same pH (Grossarenic Paleudult, 92% sand, 1% organic matter). Some soil and ash were left unamended as non-mycorrhizal controls. Cucumber (Cucumis sativus L. cv. Poinsette 76) seeds were sown, watered regularly, and fertilized periodically with macronutrient solution. By 8 weeks all ash-grown plants exhibited smaller leaves with leaf margin curl and necrosis, and plant biomass was significantly less (0.75x) than soil-grown plants. Based on analysis of 18 elements in plant tissues, toxicity to B, Mn, or Zn could have caused growth suppression, confirming trace element problems for plant growth on fly ash. For plants grown on fly ash, G. etunicatum was the only fungus that colonized roots (20% of root length reduced from 67% on soil) and it suppressed plant growth to 0.80 x that of uninoculated ash-grown plants. Correspondingly, shoot Zn concentration in G. etunicatum-inoculated plants was 3.5 x higher than in uninoculated plants and at generally toxic levels (273 mg kg[sup -1]). Glomus etunicatum had no other significant effects on elemental concentrations. These results indicate that VAM colonization in acid, weathered fly ash suppressed plant growth by facilitating uptake of Zn to toxic levels, and implies a limitation to successful use of VAM for vegetation establishment on abandoned coal fly ash basins.

Liquefaction resistance of calcareous sands

International Nuclear Information System (INIS)

Sandoval Vallejo, Eimar

2012-01-01

Calcareous sands are unique in terms of their origin, mineralogy, shape, fragility and intra particle porosity. This article presents results from an experimental program carried out to study the liquefaction resistance of a calcareous sand retrieved from Cabo Rojo at Puerto Rico. The experimental program included mineralogical characterization, index properties, and undrained cyclic triaxial tests on isotropically consolidated reconstituted samples. Due to the large variation in the calcareous sand properties, results are compared with previous researches carried out on other calcareous sands around the world. Results showed a wide range in the liquefaction resistance of the studied calcareous sands. Cabo Rojo sand experienced greater liquefaction resistance than most of the calcareous sands used for comparison. Important differences in the excess pore pressure generation characteristics were also found.

Researches Regarding the Adaptation Process of the Species Miscanthus Giganteus under the Conditions of Fly Ash Deposit from Utvin, Timis County

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Benoni Lixandru

2013-05-01

Full Text Available Miscanthus giganteus is a large, perennial (up to 20 years grass hybrid of M. sinensis and M. sacchariflorus native to Japan. Is a C4 carbon fixation plant, and thus exhibits greater photosynthetic efficiency and lower water use requirements than other kinds of plants. It has very low nutritional requirements – it has high nitrogen use efficiency and therefore is capable of growing well on barren land without the aid of heavy fertilization. M. giganteus is a sterile hybrid, therefore propagates vegetative through its rhizomes and that it is a completely non-invasive species. In this paper are presented the results of this grass species growing on fly ash deposit Utvin after the first year from the planting. Order to stimulate the process of vegetative from the first year, have used three different fertilizing: with sewage sludge, with cattle manure and mineral supplement such as N.P.K. We have also provided an adequate irrigation during dry periods of the summer. The best germination percentage was obtained in variants fertilized with sewage sludge and manure of cattle. Further the same variations recorded a good growth rate and higher biomass production. However, good production of biomass produced in the first year of all variants show a good adaptability of the species M. giganteus to arid biotope conditions of the fly ash dump.

Utilization of fly ash for stabilization/solidification of heavy metal contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Dermatas, D.; Meng, X. [Stevens Inst. of Technology, Hoboken, NJ (United States)

1995-12-01

Pozzolanic-based stabilization/solidification (S/S) is an effective, yet economic technological alternative to immobilize heavy metals in contaminated soils and sludges. Fly ash waste materials were used along with quicklime (CaO) to immobilize lead, trivalent and hexavalent chromium present in contaminated clayey sand soils. The degree of heavy metal immobilization was evaluated using the Toxicity Characteristic Leaching Procedure (TCLP) as well as controlled extraction experiments. These leaching test results along with X-ray diffraction (XRD), scanning electron microscope and energy dispersive x-ray (SEM-EDX) analyses were also implemented to elucidate the mechanisms responsible for immobilization of the heavy metals under study. Finally, the reusability of the stabilized waste forms in construction applications was also investigated by performing unconfined compressive strength and swell tests. Results suggest that the controlling mechanism for both lead and hexavalent chromium immobilization is surface adsorption, whereas for trivalent chromium it is hydroxide precipitation. Addition of fly ash to the contaminated soils effectively reduced heavy metal leachability well below the non-hazardous regulatory limits. However, quicklime addition was necessary in order to attain satisfactory immobilization levels. Overall, fly ash addition increases the immobilization pH region for all heavy metals tested, and significantly improves the stress-strain properties of the treated solids, thus allowing their reuse as readily available construction materials. The only potential problem associated with this quicklime/fly ash treatment is the excessive formation of the pozzolanic product ettringite in the presence of sulfates. Ettringite, when brought in contact with water, may cause significant swelling and subsequent deterioration of the stabilized matrix. Addition of minimum amounts of barium hydroxide was shown to effectively eliminate ettringite formation.

Development of UHPC mixtures utilizing natural and industrial waste materials as partial replacements of silica fume and sand.

Science.gov (United States)

Ahmad, Shamsad; Hakeem, Ibrahim; Maslehuddin, Mohammed

2014-01-01

In the exploratory study presented in this paper, an attempt was made to develop different mixtures of ultrahigh performance concrete (UHPC) using various locally available natural and industrial waste materials as partial replacements of silica fume and sand. Materials such as natural pozzolana (NP), fly ash (FA), limestone powder (LSP), cement kiln dust (CKD), and pulverized steel slag (PSS), all of which are abundantly available in Saudi Arabia at little or no cost, were employed in the development of the UHPC mixtures. A base mixture of UHPC without replacement of silica fume or sand was selected and a total of 24 trial mixtures of UHPC were prepared using different percentages of NP, FA, LSP, CKD, and PSS, partially replacing the silica fume and sand. Flow and 28-d compressive strength of each UHPC mixture were determined to finally select those mixtures, which satisfied the minimum flow and strength criteria of UHPC. The test results showed that the utilization of NP, FA, LSP, CKD, and PSS in production of UHPC is possible with acceptable flow and strength. A total of 10 UHPC mixtures were identified with flow and strength equal to or more than the minimum required.

The Effect of Variation of Molarity of Alkali Activator and Fine Aggregate Content on the Compressive Strength of the Fly Ash: Palm Oil Fuel Ash Based Geopolymer Mortar

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Iftekhair Ibnul Bashar

2014-01-01

Full Text Available The effect of molarity of alkali activator, manufactured sand (M-sand, and quarry dust (QD on the compressive strength of palm oil fuel ash (POFA and fly ash (FA based geopolymer mortar was investigated and reported. The variable investigated includes the quantities of replacement levels of M-sand, QD, and conventional mining sand (N-sand in two concentrated alkaline solutions; the contents of alkaline solution, water, POFA/FA ratio, and curing condition remained constant. The results show that an average of 76% of the 28-day compressive strength was found at the age of 3 days. The rate of strength development from 3 to 7 days was found between 12 and 16% and it was found much less beyond this period. The addition of 100% M-sand and QD shows insignificant strength reduction compared to mixtures with 100% N-sand. The particle angularity and texture of fine aggregates played a significant role in the strength development due to the filling and packing ability. The rough texture and surface of QD enables stronger bond between the paste and the fine aggregate. The concentration of alkaline solution increased the reaction rate and thus enhanced the development of early age strength. The use of M-sand and QD in the development of geopolymer concrete is recommended as the strength variation between these waste materials and conventional sand is not high.

MECHANICAL REGENERATION OF SAND WASTE

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D. I. Gnir

2005-01-01

Full Text Available The experimental activation of the sand regenerator of the firm SINTO is carried out at ОАО “MZOO". It is shown that sand grains are cleared from films of binding agents, that allows to use the treated sand for preparation of agglutinant and core sands.

Association of Lutzomyia columbiana (Diptera: Psychodidae) with a leishmaniasis focus in Colombia due to species of the Leishmania mexicana complex.

Science.gov (United States)

Montoya-Lerma, J; Cadena, H; Segura, I; Travi, B L

1999-01-01

In Colombia, Leishmania mexicana has a scattered geographical distribution and no sand fly vectors have been associated with its transmission. During the present study, the anthropophilic sand fly Lutzomyia columbiana was found to be the only species collected using diverse methods, in a small focus of Le. mexicana in the municipality of Samaniego, SW Colombia. Ecological data indicate that this sand fly species is present in both peri and intradomestic habitats, where it readily bites man. Further evidence comes from experimental infections of wild-caught Lu. columbiana with Le. mexicana after feeding on infected hamsters. Based on these results, it is suggested that this sand fly is the most likely vector in the study area, suggesting the existence of a previously unknown sand fly-parasite association.

Clocks do not tick in unison: isolation of Clock and vrille shed new light on the clockwork model of the sand fly Lutzomyia longipalpis.

Science.gov (United States)

Gesto, João Silveira Moledo; Rivas, Gustavo Bueno da Silva; Pavan, Marcio Galvão; Meireles-Filho, Antonio Carlos Alves; Amoretty, Paulo Roberto de; Souza, Nataly Araújo de; Bruno, Rafaela Vieira; Peixoto, Alexandre Afranio

2015-10-06

Behavior rhythms of insect vectors directly interfere with the dynamics of pathogen transmission to humans. The sand fly Lutzomyia longipalpis is the main vector of visceral leishmaniasis in America and concentrates its activity around dusk. Despite the accumulation of behavioral data, very little is known about the molecular bases of the clock mechanism in this species. This study aims to characterize, within an evolutionary perspective, two important circadian clock genes, Clock and vrille. We have cloned and isolated the coding sequence of L. longipalpis' genes Clock and vrille. The former is structured in eight exons and encodes a protein of 696 amino acids, and the latter comprises three exons and translates to a protein of 469 amino acids. When compared to other insects' orthologues, L. longipalpis CLOCK shows a high degree of conservation in the functional domains bHLH and PAS, but a much shorter glutamine-rich (poly-Q) C-terminal region. As for L. longipalpis VRILLE, a high degree of conservation was found in the bZIP domain. To support these observations and provide an elegant view of the evolution of both genes in insects, phylogenetic analyses based on maximum-likelihood and Bayesian inferences were performed, corroborating the previously known insect systematics. The isolation and phylogenetic analyses of Clock and vrille orthologues in L. longipalpis bring novel and important data to characterize this species' circadian clock. Interestingly, the poly-Q shortening observed in CLOCK suggests that its transcription activity might be impaired and we speculate if this effect could be compensated by other clock factors such as CYCLE.

indigenous cattle breeds

African Journals Online (AJOL)

Received 31 August 1996; accepted 20 March /998. Mitochondrial DNA cleavage patterns from representative animals of the Afrikaner and Nguni sanga cattle breeds, indigenous to Southern Africa, were compared to the mitochondrial DNA cleavage patterns of the Brahman (zebu) and the Jersey. (taurine) cattle breeds.

Investigations of the technical possibilities for the use of fly ash: the concrete industry as a market. Marktbeschrijving betonwarenindustrie ten behoeve van het onderzoek naar de technische mogelijkheden van het gebruik van vliegas

Energy Technology Data Exchange (ETDEWEB)

1982-01-01

Desk research (analysis of the production figures of concrete) and field research (personal discussions with producers and merchants) are carried out to investigate whether the application of fly ash in the production of concrete is feasible. The introduction of fly ash depends on the properties of the final product and of the properties during the process of curing, and these depend on a large number of factors such as cement/sand ratio, quality of cement, specifications of the final product. Products such as paving stones, tiles and blocks are favourable for the application of fly ash in concrete. Building elements, pipes and floor elements are not. Market structure in The Netherlands is outlined and mapped, and the present use of fly ash in the concrete industry is discussed. (In Dutch)

Improvement of Shear Strength of Sandy Soil by Cement Grout with Fly Ash

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Haifaa Abdulrasool Ali

2018-12-01

Full Text Available The effects of the permeation cement grout with fly ash on the sandy soil skeleton were studied in the present work in two phase; first phase the shear strength parameters, and the second phase effect of these grouted materials on volume grouted zone by injection (51 cm³ of slurry in sandy soil placed in steel cylinder model with dimension 15 cm in diameter and 30 cm in height. The soil sample was obtained from Karbala city and it is classified as poorly graded sand (SP according to USCS. The soil samples were improved by cement grout with three percentages weight of water cement ratio (w:c; (0.1w:0.9c, 0.8w:0.2c, and 0.7w:0.3c, while the soil samples were dehydrated for one day curing time. Fly ash class (F was used with cement grout as filler material; it was added to the mixture as a replacement material for cement in weight percentages; 10%, 25% and 40%. According to the results of tests, both shear strength and approximate volume of the effective grouted zone for treated samples soil with cement grout was increased when the water cement ratio decreased. Fly ash with cement grout needs to increase the water demand for the grout mixing to give best results in both shear strength and filling the soil voids.

Crushed rock sand – An economical and ecological alternative to natural sand to optimize concrete mix

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Sanjay Mundra

2016-09-01

Full Text Available The study investigates the use of crushed rock sand as viable alternative to Natural River sand that is being conventionally used as fine aggregate in cement concrete. Various mix designs were developed for different grades of concrete based on IS, ACI and British codes using Natural River sand and crushed rock sand. In each case, the cube compressive strength test, and beam flexure tests were conducted. The results of the study show that, the strength properties of concrete using crushed rock sand are nearly similar to the conventional concrete. The study has shown that crushed stone sand can be used as economic and readily available alternative to river sand and can therefore help to arrest the detrimental effects on the environment caused due to excessive mining of river sand.

7 CFR 1260.118 - Cattle.

Science.gov (United States)

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false Cattle. 1260.118 Section 1260.118 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Promotion and Research Order Definitions § 1260.118 Cattle. Cattle means live domesticated bovine animals...

Susceptibility to chemical insecticides of two Brazilian populations of the visceral leishmaniasis vector Lutzomyia longipalpis (Diptera: Psychodidae).

Science.gov (United States)

Alexander, B; Barros, V C; de Souza, S F; Barros, S S; Teodoro, L P; Soares, Z R; Gontijo, N F; Reithinger, R

2009-10-01

To investigate the insecticide susceptibility of two geographically separated Lutzomyia longipalpis populations (Lapinha and Montes Claros) with different histories of insecticide exposure (i.e. no exposure and repeated exposure, respectively). (i) Bioassay monitoring of sand fly survival over time when exposed to a range of insecticides; and (ii) analysis of the level of insecticide detoxification enzymes in individual sand flies caught at both study sites. Insecticides tested were the organophosphates malathion and fenitrothion and the pyrethroids lambda-cyhalothrin, permethrin and deltamethrin. Survival analyses showed that whilst there was no overall significant difference in susceptibility of both populations to organophosphates, Lapinha sand flies were significantly more susceptible to pyrethroids than those from Montes Claros. Multiple regression analyses also showed that insecticide susceptibility in both locations varied with sand fly sex. The relative susceptibilities of the two sand fly populations to tested insecticides were also compared. Thus, Montes Claros sand flies were most susceptible to malathion, followed by fenitrothion, deltamethrin and permethrin. Those from Lapinha were most susceptible to lambda-cyhalothrin, followed by malathion, permethrin, deltamethrin and fenitrothion. Biochemical analyses demonstrated that Montes Claros sand flies had significantly lower insecticide detoxification enzyme activity than Lapinha sand flies. Our results are the first record of significantly reduced susceptibility to the insecticides used in control of wild populations of Lu. longipalpis. They demonstrate the importance of evaluating chemicals against this species by conventional bioassay and microplate assays before and during spraying programmes.

Can E. coli fly?

DEFF Research Database (Denmark)

Lindeberg, Yrja Lisa; Egedal, Karen; Hossain, Zenat Zebin

2018-01-01

, and the numbers of flies landing on the exposed rice were counted. Following exposure, the surface of the rice was microbiologically and molecularly analysed for the presence of E. coli and genes of diarrheagenic E. coli and Shigella strains. RESULTS: Rice was at greater risk (p ... with E. coli if flies landed on the rice than if no flies landed on the rice (odds ratio 5·4 (p ...-landings, the average CFU per fly-landing was > 0·6 x 103 CFU. Genes of diarrheagenic E. coli and Shigella species were detected in 39 of 60 (65%) of exposed rice samples. Two fly species were identified; the common housefly (Musca domestica) and the oriental latrine fly (Chrysomya megacephala). CONCLUSION: Flies may...

Impacto de alterações ambientais na ecologia de flebotomíneos no sul do Brasil Impact of environmental changes on sand fly ecology in southern Brazil

Directory of Open Access Journals (Sweden)

Ueslei Teodoro

1999-10-01

Full Text Available Verificou-se que a abertura de uma clareira ao redor de um galinheiro e aplicações periódicas de inseticidas refletiram na ecologia das espécies de flebotomíneos na Fazenda Palmital, município de Terra Boa, Estado do Paraná, sul do Brasil. A espécie dominante (51,6% antes do desmatamento e das aplicações de inseticidas era Lutzomyia migonei (França, 1920. Após estas medidas, Lutzomyia (Nyssomyia whitmani (Antunes & Coutinho, 1939 passou a predominar (89,8%. A diferença de proporções de L. whitmani nesta investigação (89,8 % em relação à outra (32,6%, realizada antes da abertura da clareira e das aplicações de inseticidas, foi altamente significativa.Tree felling around a chicken coop and periodic insecticide spraying at the Palmital farm in the county of Terra Boa in southern Brazil impacted the ecology of sand fly species. The most prevalent species (51.6% before clearing the trees and insecticide spraying was Lutzomyia migonei (França, 1920, and it is now Lutzomyia (Nyssomyia whitmani (Antunes & Coutinho, 1939 (89.8%. There was a highly significant difference between the proportions of L. whitmani reported by this paper (89.8% and another publication before the tree felling and insecticide spraying (32.6%.

Morphological characterization ofMadura Cattle

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Bambang Setiadi

1998-12-01

Full Text Available Morphological characterization of Madura cattle in Madura islands was done as an input for "action plans" of national animals genetic resources management according to the global system ofFAO. Assessments were done in Sumenep District and Pamekasan District, East Java. According to the body measurements, Madura cattle can be classified as a small to medium type with withers height of about 120 cm. Because of potential productivity in the limitation of environmental resources, Madura cattle can be classified as a "superior" cattle . Body measurements of Madura cattle in the present study were relatively the same with those of 50 years ago, indicating that there is no breeding improvement activities except natural selection . The variability of body measurements is relatively narrow . Improving productivity by outbreeding is needed . To conserve the unique germ plasm of the Indonesian genotype, such as Madura cattle and a possibility to improve their productivity by a complete prevention of cross breeding in the Madura islands needs further evaluation .

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.

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...

Chromosome analysis of arsenic affected cattle

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S. Shekhar

2014-10-01

Full Text Available Aim: The aim was to study the chromosome analysis of arsenic affected cattle. Materials and Methods: 27 female cattle (21 arsenic affected and 6 normal were selected for cytogenetical study. The blood samples were collected, incubated, and cultured using appropriate media and specific methods. The samples were analyzed for chromosome number and morphology, relative length of the chromosome, arm ratio, and centromere index of X chromosome and chromosomal abnormalities in arsenic affected cattle to that of normal ones. Results: The diploid number of metaphase chromosomes in arsenic affected cattle as well as in normal cattle were all 2n=60, 58 being autosomes and 2 being sex chromosomes. From the centromeric position, karyotyping studies revealed that all the 29 pair of autosomes was found to be acrocentric or telocentric, and the sex chromosomes (XX were submetacentric in both normal and arsenic affected cattle. The relative length of all the autosome pairs and sex chrosomosome pair was found to be higher in normal than that of arsenic affected cattle. The mean arm ratio of X-chromosome was higher in normal than that of arsenic affected cattle, but it is reverse in case of centromere index value of X-chromosome. There was no significant difference of arm ratio and centromere index of X-chromosomes between arsenic affected and normal cattle. No chromosomal abnormalities were found in arsenic affected cattle. Conclusion: The chromosome analysis of arsenic affected cattle in West Bengal reported for the first time in this present study which may serve as a guideline for future studies in other species. These reference values will also help in comparison of cytological studies of arsenic affected cattle to that of various toxicants.

Rheological Characterization of Green Sand Flow

DEFF Research Database (Denmark)

Jabbaribehnam, Mirmasoud; Spangenberg, Jon; Hovad, Emil

2016-01-01

The main aim of this paper is to characterize experimentally the flow behaviour of the green sand that is used for casting of sand moulds. After the sand casting process is performed, the sand moulds are used for metal castings. The rheological properties of the green sand is important to quantif...

Properties and Leachability of Self-Compacting Concrete Incorporated with Fly Ash and Bottom Ash

Science.gov (United States)

Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Jamaluddin, Norwati; Bakri Abdullah, Mohd Mustafa Al

2016-06-01

The process of combustion in coal-fired power plant generates ashes, namely fly ash and bottom ash. Besides, coal ash produced from coal combustion contains heavy metals within their compositions. These metals are toxic to the environment as well as to human health. Fortunately, treatment methods are available for these ashes, and the use of fly ash and bottom ash in the concrete mix is one of the few. Therefore, an experimental program was carried out to study the properties and determine the leachability of selfcompacting concrete incorporated with fly ash and bottom ash. For experimental study, self-compacting concrete was produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a replacement for sand with the ratios of 10%, 20%, and 30% respectively. The fresh properties tests conducted were slump flow, t500, sieve segregation and J-ring. Meanwhile for the hardened properties, density, compressive strength and water absorption test were performed. The samples were then crushed to be extracted using Toxicity Characteristic Leaching Procedure and heavy metals content within the samples were identified accordingly using Atomic Absorption Spectrometry. The results demonstrated that both fresh and hardened properties were qualified to categorize as self-compacting concrete. Improvements in compressive strength were observed, and densities for all the samples were identified as a normal weight concrete with ranges between 2000 kg/m3 to 2600 kg/m3. Other than that, it was found that incorporation up to 30% of the ashes was safe as the leached heavy metals concentration did not exceed the regulatory levels, except for arsenic. In conclusion, this study will serve as a reference which suggests that fly ash and bottom ash are widely applicable in concrete technology, and its incorporation in self-compacting concrete constitutes a potential means of adding value to appropriate mix and design.

Mercury release from fly ashes and hydrated fly ash cement pastes

Science.gov (United States)

Du, Wen; Zhang, Chao-yang; Kong, Xiang-ming; Zhuo, Yu-qun; Zhu, Zhen-wu

2018-04-01

The large-scale usage of fly ash in cement and concrete introduces mercury (Hg) into concrete structures and a risk of secondary emission of Hg from the structures during long-term service was evaluated. Three fly ashes were collected from coal-fired power plants and three blend cements were prepared by mixing Ordinary Portland cement (OPC) with the same amount of fly ash. The releasing behaviors of Hg0 from the fly ash and the powdered hydrated cement pastes (HCP) were measured by a self-developed Hg measurement system, where an air-blowing part and Hg collection part were involved. The Hg release of fly ashes at room temperature varied from 25.84 to 39.69 ng/g fly ash during 90-days period of air-blowing experiment. In contrast, the Hg release of the HCPs were in a range of 8.51-18.48 ng/g HCP. It is found that the Hg release ratios of HCPs were almost the same as those of the pure fly ashes, suggesting that the hydration products of the HCP have little immobilization effect on Hg0. Increasing temperature and moisture content markedly promote the Hg release.

Association of Lutzomyia columbiana (Diptera: Psychodidae with a Leishmaniasis Focus in Colombia Due to Species of the Leishmania mexicana Complex

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James Montoya-lerma

1999-05-01

Full Text Available In Colombia, Leishmania mexicana has a scattered geographical distribution and no sand fly vectors have been associated with its transmission. During the present study, the anthropophilic sand fly Lutzomyia columbiana was found to be the only species collected using diverse methods, in a small focus of Le. mexicana in the municipality of Samaniego, SW Colombia. Ecological data indicate that this sand fly species is present in both peri and intradomestic habitats, where it readily bites man. Further evidence comes from experimental itnfections of wild-caught Lu. columbiana with Le. mexicana after feeding on itnfected hamsters. Based on these results, it is suggested that this sand fly is the most likely vector in the study area, suggesting the existence of a previously unknown sand fly-parasite association.

Description of Lutzomyia (Trichophoromyia) nautaensis n. sp. (Diptera: Psychodidae) from the Peruvian Amazon Basin.

Science.gov (United States)

Fernandez, Roberto; Lopez, Victor; Cardenas, Roldan; Requena, Edwin

2015-07-01

A new species of sand fly, which we describe as Lutzomyia (Trichophoromyia) nautaensis n. sp., was collected in the northern Peruvian Amazon Basin. In this region of Peru, cutaneous leishmaniasis is transmitted primarily by anthropophilic sand flies; however, zoophilic sand flies of the subgenus Trichophoromyia may also be incriminated in disease transmission. Detection of Leishmania spp. in Lutzomyia auraensis Mangabeira captured in the southern Peruvian Amazon indicates the potential of this and other zoophilic sand flies for human disease transmission, particularly in areas undergoing urban development. Herein, we describe Lutzomyia (Trichophoromyia) nautaensis n. sp., and report new records of sand flies in Peru. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

The Gut Microbiome of the Vector Lutzomyia longipalpis Is Essential for Survival of Leishmania infantum.

Science.gov (United States)

Kelly, Patrick H; Bahr, Sarah M; Serafim, Tiago D; Ajami, Nadim J; Petrosino, Joseph F; Meneses, Claudio; Kirby, John R; Valenzuela, Jesus G; Kamhawi, Shaden; Wilson, Mary E

2017-01-17

The vector-borne disease leishmaniasis, caused by Leishmania species protozoa, is transmitted to humans by phlebotomine sand flies. Development of Leishmania to infective metacyclic promastigotes in the insect gut, a process termed metacyclogenesis, is an essential prerequisite for transmission. Based on the hypothesis that vector gut microbiota influence the development of virulent parasites, we sequenced midgut microbiomes in the sand fly Lutzomyia longipalpis with or without Leishmania infantum infection. Sucrose-fed sand flies contained a highly diverse, stable midgut microbiome. Blood feeding caused a decrease in microbial richness that eventually recovered. However, bacterial richness progressively decreased in L. infantum-infected sand flies. Acetobacteraceae spp. became dominant and numbers of Pseudomonadaceae spp. diminished coordinately as the parasite underwent metacyclogenesis and parasite numbers increased. Importantly, antibiotic-mediated perturbation of the midgut microbiome rendered sand flies unable to support parasite growth and metacyclogenesis. Together, these data suggest that the sand fly midgut microbiome is a critical factor for Leishmania growth and differentiation to its infective state prior to disease transmission. Leishmania infantum, a parasitic protozoan causing fatal visceral leishmaniasis, is transmitted to humans through the bite of the sand fly Lutzomyia longipalpis Development of the parasite to its virulent metacyclic state occurs in the sand fly gut. In this study, the microbiota within the Lu. longipalpis midgut was delineated by 16S ribosomal DNA (rDNA) sequencing, revealing a highly diverse community composition that lost diversity as parasites developed to their metacyclic state and increased in abundance in infected flies. Perturbing sand fly gut microbiota with an antibiotic cocktail, which alone had no effect on either the parasite or the fly, arrested both the development of virulent parasites and parasite expansion

The Alberta oil sands story

Energy Technology Data Exchange (ETDEWEB)

1974-01-01

This report serves as a detailed introduction to the Alberta oil sands and their development. It includes a description of the oil sands deposits, an outline of crude bitumen recovery and upgrading processes, the role of Alberta Energy Company in oil sands development, environmental aspects, manpower requirements for oil sands development, research needs, and further oil sands projects. Presently proven recoverable reserves in the oil sands amount to 26.5 billion bbl of synthetic crude. Production from the Syncrude plant (125,000 bbl/d capacity) is expected to begin in 1977, followed by a Shell Canada operation around 1980. The provincial government will participate in the oil sand industry through its joint venture participation in Syncrude and its 50% share in Alberta Energy Company; the latter company participates in related aspects of the Syncrude project, such as pipelines. The result of Alberta's participation in the industry will mean that, directly or indirectly, the province will realize 60% of the total profits. The job creation potential of oil sands projects is estimated to be extensive, with a direct and indirect work force supported by oil sands activities possibly reaching 180,000 persons by the year 2000. Research needs have been identified, particularly in the area of in-situ thermal recovery technology, and the creation of the Alberta Oil Sands Technology and Research Authority has been authorized in order to meet these needs. Although current reserves are sufficient to support 20-30 synthetic crude plants, a number of factors will limit expansion of the industry. 8 figs., 5 tabs.

Fly ash aggregates. Vliegaskunstgrind

Energy Technology Data Exchange (ETDEWEB)

1983-03-01

A study has been carried out into artificial aggregates made from fly ash, 'fly ash aggregates'. Attention has been drawn to the production of fly ash aggregates in the Netherlands as a way to obviate the need of disposal of fly ash. Typical process steps for the manufacturing of fly ash aggregates are the agglomeration and the bonding of fly ash particles. Agglomeration techniques are subdivided into agitation and compaction, bonding methods into sintering, hydrothermal and 'cold' bonding. In sintering no bonding agent is used. The fly ash particles are more or less welded together. Sintering in general is performed at a temperature higher than 900 deg C. In hydrothermal processes lime reacts with fly ash to a crystalline hydrate at temperatures between 100 and 250 deg C at saturated steam pressure. As a lime source not only lime as such, but also portland cement can be used. Cold bonding processes rely on reaction of fly ash with lime or cement at temperatures between 0 and 100 deg C. The pozzolanic properties of fly ash are used. Where cement is applied, this bonding agent itself contributes also to the strength development of the artificial aggregate. Besides the use of lime and cement, several processes are known which make use of lime containing wastes such as spray dry absorption desulfurization residues or fluid bed coal combustion residues. (In Dutch)

Hydration of fly ash cement and microstructure of fly ash cement pastes

Energy Technology Data Exchange (ETDEWEB)

Shiyuan, H.

1981-01-01

The strength development and hydration of fly ash cement and the influence of addition of gypsum on those were studied at normal and elevated temperatures. It was found that an addition of a proper amount of gypsum to fly ash cement could accelerate the pozzolanic reaction between CH and fly ash, and as a result, increase the strength of fly ash cement pastes after 28 days.

Evaluation of the ecological characteristics in the vector of anthroponotic cutaneous leishmaniasis in a new focus of Mohammad Abad, Kerman, southeast of Iran

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Abbas Aghaei Afshar

2017-02-01

Full Text Available Objective: To evaluate the fauna, seasonal activity and the host preference of sand flies and to determine the main vectors of anthroponotic cutaneous leishmaniasis in Mohammad Abad, Kerman Province, southeast of Iran. Methods: Sand flies were collected indoors and outdoors by sticky paper traps from May to November, 2012. Regarding the importance of host preference and its impact on leishmaniasis control, blood meal was analyzed by the restriction fragment length polymorphism method. The cytochrome b mitochondrial genomic regions (mitochondrial DNA and enzymatic digestion of Xho I and Hae III were used for the diagnosis of human blood feeding. In the detection of leptomonad (promastigote infection in sand flies, a nested PCR method and high resolution melt analysis were exploited. Results: A total of 919 sand flies were identified as belonging to 14 species in two genera, namely, Phlebotomus spp. (5 species and Sergentomyia spp. (9 species. The most frequently occurring species was Phlebotomus sergenti (P. sergenti (67.46%, followed by Phlebotomus papatasi (19.37%. The highest indoor collection of P. sergenti was realized in late July, and the highest outdoor collection of P. sergenti ensued in early July. A total of 250 sand flies were collected for host preference analysis, and blood meals of 120 sand flies belonged to the species of P. sergenti were subjected to restriction fragment length polymorphism confirmation. A total of 39 P. sergenti sand flies (32.5% were identified to have fed on human. NestedPCR and high resolution melt analyses confirmed that these sand flies had been infected with Leishmania tropica. Conclusions: The present study has confirmed P. sergenti as the main Phlebotomine sand fly vector for anthroponotic cutaneous leishmaniasis caused by Leishmania tropica in Southeastern Iran.

Cattle phenotypes can disguise their maternal ancestry.

Science.gov (United States)

Srirattana, Kanokwan; McCosker, Kieren; Schatz, Tim; St John, Justin C

2017-06-26

Cattle are bred for, amongst other factors, specific traits, including parasite resistance and adaptation to climate. However, the influence and inheritance of mitochondrial DNA (mtDNA) are not usually considered in breeding programmes. In this study, we analysed the mtDNA profiles of cattle from Victoria (VIC), southern Australia, which is a temperate climate, and the Northern Territory (NT), the northern part of Australia, which has a tropical climate, to determine if the mtDNA profiles of these cattle are indicative of breed and phenotype, and whether these profiles are appropriate for their environments. A phylogenetic tree of the full mtDNA sequences of different breeds of cattle, which were obtained from the NCBI database, showed that the mtDNA profiles of cattle do not always reflect their phenotype as some cattle with Bos taurus phenotypes had Bos indicus mtDNA, whilst some cattle with Bos indicus phenotypes had Bos taurus mtDNA. Using D-loop sequencing, we were able to contrast the phenotypes and mtDNA profiles from different species of cattle from the 2 distinct cattle breeding regions of Australia. We found that 67 of the 121 cattle with Bos indicus phenotypes from NT (55.4%) had Bos taurus mtDNA. In VIC, 92 of the 225 cattle with Bos taurus phenotypes (40.9%) possessed Bos indicus mtDNA. When focusing on oocytes from cattle with the Bos taurus phenotype in VIC, their respective oocytes with Bos indicus mtDNA had significantly lower levels of mtDNA copy number compared with oocytes possessing Bos taurus mtDNA (P cattle with a Bos taurus phenotype. The phenotype of cattle is not always related to their mtDNA profiles. MtDNA profiles should be considered for breeding programmes as they also influence phenotypic traits and reproductive capacity in terms of oocyte quality.

Compressive behavior of fine sand.

Energy Technology Data Exchange (ETDEWEB)

Martin, Bradley E. (Air Force Research Laboratory, Eglin, FL); Kabir, Md. E. (Purdue University, West Lafayette, IN); Song, Bo; Chen, Wayne (Purdue University, West Lafayette, IN)

2010-04-01

The compressive mechanical response of fine sand is experimentally investigated. The strain rate, initial density, stress state, and moisture level are systematically varied. A Kolsky bar was modified to obtain uniaxial and triaxial compressive response at high strain rates. A controlled loading pulse allows the specimen to acquire stress equilibrium and constant strain-rates. The results show that the compressive response of the fine sand is not sensitive to strain rate under the loading conditions in this study, but significantly dependent on the moisture content, initial density and lateral confinement. Partially saturated sand is more compliant than dry sand. Similar trends were reported in the quasi-static regime for experiments conducted at comparable specimen conditions. The sand becomes stiffer as initial density and/or confinement pressure increases. The sand particle size become smaller after hydrostatic pressure and further smaller after dynamic axial loading.

Ommatidia of blow fly, house fly, and flesh fly: implication of their vision efficiency.