Spatial dynamics of urban populations of Lutzomyia longipalpis (Diptera: Psychodidae in Caxias, State of Maranhão, Brazil

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Maria do Desterro Soares Brandao Nascimento

2013-09-01

Full Text Available Introduction In this paper, we report the ecology of Lutzomyia longipalpis in Caxias City, located in the eastern part of State of Maranhão, Brazil and highlight its seasonal and geographical distribution by environment. In addition, we discuss natural Leishmania infection and its relationship with visceral leishmaniasis. Methods Between September 2007 and August 2009, the collection of sandflies was performed using Center for Disease Control (CDC light traps from 15 houses in 5 selected neighborhoods. Results Lutzomyia longipalpis was present in all zones of the city. We also found that Lu. longipalpis was regularly detected both inside and around the house, predominantly in outdoor areas. In urban areas, Lu. longipalpis was present in both the dry and rainy seasons, with a higher density present in the latter. One female specimen of Lu. longipalpis was observed to have natural Leishmania infection. Conclusions The presence of Lu. longipalpis was observed throughout the year during 2 seasonal periods, with a predominance in the rainy season. A low rate of natural Leishmania infection was observed in urban areas during the rainy season.

Spatial dynamics of urban populations of Lutzomyia longipalpis (Diptera: Psychodidae) in Caxias, State of Maranhão, Brazil.

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Nascimento, Maria do Desterro Soares Brandão; Silva, Maria Helena; Viana, Graça Maria de Castro; Leonardo, Francisco Santos; Bezerra, Geusa Felipa de Barros; Silva, Antonia Suely Guimarães e; Soares, Valéria Cristina Pinheiro; Pereira, Silma Regina Ferreira; Rebêlo, José Manuel Macário; Brazil, Reginaldo Peçanha

2013-01-01

In this paper, we report the ecology of Lutzomyia longipalpis in Caxias City, located in the eastern part of State of Maranhão, Brazil and highlight its seasonal and geographical distribution by environment. In addition, we discuss natural Leishmania infection and its relationship with visceral leishmaniasis. Between September 2007 and August 2009, the collection of sandflies was performed using Center for Disease Control (CDC) light traps from 15 houses in 5 selected neighborhoods. Lutzomyia longipalpis was present in all zones of the city. We also found that Lu. longipalpis was regularly detected both inside and around the house, predominantly in outdoor areas. In urban areas, Lu. longipalpis was present in both the dry and rainy seasons, with a higher density present in the latter. One female specimen of Lu. longipalpis was observed to have natural Leishmania infection. The presence of Lu. longipalpis was observed throughout the year during 2 seasonal periods, with a predominance in the rainy season. A low rate of natural Leishmania infection was observed in urban areas during the rainy season.

The taxonomic status of genetically divergent populations of Lutzomyia longipalpis (Diptera: Psychodidae) based on the distribution of mitochondrial and isozyme variation.

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Arrivillaga, Jazzmin; Mutebi, John-Paul; Piñango, Hermes; Norris, Douglas; Alexander, Bruce; Feliciangeli, M Dora; Lanzaro, Gregory C

2003-09-01

The sand fly, Lutzomyia longipalpis (Lutz & Neiva) reputedly is a complex of cryptic species; however, there is currently no consensus as to the number of species in the complex or their geographic distributions. We conducted phylogenetic analyses of 31 populations from throughout the species range, using seven isozyme loci and genes in the mitochondrial genome. Analyses of these two independent sets of markers were largely concordant and revealed four distinct clades that support the existence of four species. The four clades have distinct geographic ranges: (1) Brazil (Species A = Lu. longipalpis sensu stricto), (2) Laran (Species B = Lu. pseudolongipalpis), (3) cis-Andean (Species C), and (4) trans-Andean (Species D). The cis-Andean clade may be subdivided further into two groups, one in Colombia and one in northwestern Venezuela, but their taxonomic status remains unresolved. Knowledge that Lu. longipalpis is a complex of species may ultimately shed light on anomalies in the epidemiology of visceral leishmaniasis in the New World.

Leishmania infantum Genetic Diversity and Lutzomyia longipalpis Mitochondrial Haplotypes in Brazil.

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Ribolla, Paulo Eduardo Martins; Gushi, Letícia Tsieme; Pires E Cruz, Maria do Socorro; Costa, Carlos Henrique Nery; Costa, Dorcas Lamounier; Lima Júnior, Manoel Sebastião da Costa; Dorval, Maria Elizabeth Moraes Cavalheiros; Gutierrez de Oliveira, Alessandra; da Cunha Santos, Mirella Ferreira; Fonseca Camargo-Neves, Vera Lúcia; Fortaleza, Carlos Magno Castello Branco; Alonso, Diego Peres

2016-01-01

Leishmania infantum is the etiological agent of visceral leishmaniasis (VL) in the Americas with domestic dogs being its major reservoir hosts. The main VL vector is the sandfly Lutzomyia longipalpis, while other Lutzomyia species may play a role in disease transmission. Although the genetic structure of L. infantum populations has been widely evaluated, only a few studies have addressed this subject coupled to the genetic structure of the respective sandfly vectors. In this study, we analyzed the population structure of L. infantum in three major VL endemic areas in Brazil and associated it with Lutzomyia longipalpis geographic structure.

Effects of temperature and photoperiod on daily activity rhythms of Lutzomyia longipalpis (Diptera: Psychodidae).

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Rivas, Gustavo B S; de Souza, Nataly Araujo; Peixoto, Alexandre A; Bruno, Rafaela V

2014-06-19

Insect vectors have been established as models in Chronobiology for many decades, and recent studies have demonstrated a close relationship between the circadian clock machinery, daily rhythms of activity and vectorial capacity. Lutzomyia longipalpis, the primary vector of Leishmania (Leishmania) infantum in the New World, is reported to have crepuscular/nocturnal activity in the wild. However, most of these studies applied hourly CDC trap captures, which is a good indicative of L. longipalpis behaviour, but has limited accuracy due to the inability to record the daily activity of a single insect during consecutive days. In addition, very little is known about the activity pattern of L. longipalpis under seasonal variations of average temperature and day length in controlled laboratory conditions. We recorded the locomotor activity of L. longipalpis males under different artificial regimes of temperature and photoperiod. First, in order to test the effects of temperature on the activity, sandflies were submitted to regimes of light/dark cycles similar to the equinox photoperiod (LD 12:12) combined with different constant temperatures (20°C, 25°C and 30°C). In addition, we recorded sandfly locomotor activity under a mild constant temperature (25°C with different day length regimes: 8 hours, 12 hours and 16 hours). L. longipalpis exhibited more activity at night, initiating dusk-related activity (onset time) at higher rather than lower temperatures. In parallel, changes of photoperiod affected anticipation as well as all the patterns of activity (onset, peak and offset time). However, under LD 16:08, sandflies presented the earliest values of maximum peak and offset times, contrary to other regimes. Herein, we showed that light and temperature modulate L. longipalpis behaviour under controlled laboratory conditions, suggesting that sandflies might use environmental information to sustain their crepuscular/nocturnal activity, as well as other important aspects as

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

Susceptibility to chemical insecticides of two Brazilian populations of the visceral leishmaniasis vector Lutzomyia longipalpis (Diptera: Psychodidae).

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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.

Sex pheromone and period gene characterization of Lutzomyia longipalpis sensu lato (Lutz & Neiva) (Diptera: Psychodidae) from Posadas, Argentina.

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Salomón, Oscar D; Araki, Alejandra S; Hamilton, James Gc; Acardi, Soraya A; Peixoto, Alexandre A

2010-11-01

Lutzomyia longipalpis s.l. is the primary vector of Leishmania (L.) infantum in the New World. In this study, male Lutzomyia longipalpis specimens from Posadas, Argentina were characterized for two polymorphic markers: the male sex pheromone and the period (per) gene. The male sex pheromone was identified as (S)-9-methylgermacrene-B, the same compound produced by Lu. longipalpis from Paraguay and many populations from Brazil. The analysis of per gene sequences revealed that the population from Argentina is significantly differentiated from previously studied Brazilian populations. Marker studies could contribute to the understanding of the distribution and spread of urban American visceral leishmaniasis, thus aiding in the design of regional surveillance and control strategies.

A laboratory evaluation of alcohols as attractants for the sandfly Lutzomyia longipalpis (Diptera:Psychodidae).

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Magalhães-Junior, Jairo Torres; Barrouin-Melo, Stella Maria; Corrêa, Arlene Gonçalves; da Rocha Silva, Flavia Benini; Machado, Vicente Estevam; Govone, José Silvio; Pinto, Mara Cristina

2014-02-06

The potential attraction from 1-octen-3-ol for sandflies has been documented; however, studies using other primary alcohols are limited. We used a wind tunnel to compare the activation and attractive behaviors in male and female Lutzomyia longipalpis using 1-octen-3-ol and three additional alcohols, 1-octanol, 1-heptanol and 1-nonanol at three different concentrations: neat (100%) and diluted in hexane (10% and 50%). The compounds 1-octen-3-ol and 1-nonanol induced a clear concentration-dependent activation and attraction response in females. In males, 1-octen-3-ol, 1-nonanol and 1-heptanol yielded the same results. L. longipalpis is attracted to 1-octen-3-ol, 1-nonanol and 1-heptanol, which are found in many plant volatiles.

Ecology of Lutzomyia longipalpis in an area of visceral leishmaniasis transmission in north-eastern Brazil.

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Costa, Pietra Lemos; Dantas-Torres, Filipe; da Silva, Fernando José; Guimarães, Vanessa Cristina Fitipaldi Veloso; Gaudêncio, Kamila; Brandão-Filho, Sinval Pinto

2013-05-01

Visceral leishmaniasis is a major public health issue in South America, where the disease is rapidly spreading. Changes in ecology and distribution of the principal vector, Lutzomyia longipalpis are among the factors accounting for the increasing incidence of the disease in this region. However, information about the ecology of L. longipalpis is still incipient, which may directly impair the implementation of effective control programs. Herein, the ecology of L. longipalpis was studied in a focus of visceral leishmaniasis in north-eastern Brazil. From August 2009 to August 2010, phlebotomine sand flies were monthly collected in four localities using CDC light traps (~37 per month) and a lantern-baited Shannon trap with mouth aspirators. A total of 24,226 phlebotomine sand flies were collected with light traps and 375 with mouth aspirators. The most abundant species was L. longipalpis, representing 97.9% of the specimens collected with light traps and 91.5% with the mouth aspirator. Other species (Lutzomyia evandroi, Lutzomyia lenti and Lutzomyia sallesi) were found in low numbers. Most phlebotomine sand flies (94.6%) were collected at chicken coops and corrals. No significant correlation was found between the monthly abundance of phlebotomine sand flies and the monthly averages of temperature, relative humidity or rainfall. However, interestingly enough, 82.4% of L. longipalpis specimens were collected in months when relative humidity surpassed 75%. This study points out that this vector is well adapted to live in different habitats and to different climate conditions. It also suggests that some north-eastern populations of L. longipalpis may be more xerotolerant than southern populations. Further studies to assess the relationship between microclimate and L. longipalpis density in different Brazilian regions are advised. Copyright © 2013 Elsevier B.V. All rights reserved.

Transcriptome exploration of the sex pheromone gland of Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae).

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González-Caballero, Natalia; Valenzuela, Jesus G; Ribeiro, José M C; Cuervo, Patricia; Brazil, Reginaldo P

2013-03-07

Molecules involved in pheromone biosynthesis may represent alternative targets for insect population control. This may be particularly useful in managing the reproduction of Lutzomyia longipalpis, the main vector of the protozoan parasite Leishmania infantum in Latin America. Besides the chemical identity of the major components of the L. longipalpis sex pheromone, there is no information regarding the molecular biology behind its production. To understand this process, obtaining information on which genes are expressed in the pheromone gland is essential. In this study we used a transcriptomic approach to explore the pheromone gland and adjacent abdominal tergites in order to obtain substantial general sequence information. We used a laboratory-reared L. longipalpis (one spot, 9-Methyl GermacreneB) population, captured in Lapinha Cave, state of Minas Gerais, Brazil for this analysis. From a total of 3,547 cDNA clones, 2,502 high quality sequences from the pheromone gland and adjacent tissues were obtained and assembled into 1,387 contigs. Through blast searches of public databases, a group of transcripts encoding proteins potentially involved in the production of terpenoid precursors were identified in the 4th abdominal tergite, the segment containing the pheromone gland. Among them, protein-coding transcripts for four enzymes of the mevalonate pathway such as 3-hydroxyl-3-methyl glutaryl CoA reductase, phosphomevalonate kinase, diphosphomevalonate descarboxylase, and isopentenyl pyrophosphate isomerase were identified. Moreover, transcripts coding for farnesyl diphosphate synthase and NADP+ dependent farnesol dehydrogenase were also found in the same tergite. Additionally, genes potentially involved in pheromone transportation were identified from the three abdominal tergites analyzed. This study constitutes the first transcriptomic analysis exploring the repertoire of genes expressed in the tissue containing the L. longipalpis pheromone gland as well as the

Development of Lutzomyia intermedia and Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae larvae in different diets

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WERMELINGER E. D.

2001-01-01

Full Text Available The objective of this research was to evaluate, in laboratory, the development of Lutzomyia intermedia and Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae larvae, vectors of leishmaniasis in Brazil, in the following diets: industrialized food for rabbits, dogs, hamsters and aquarium fishes, besides liver powder, cooked lettuce, wheat germ, beer yeast, oat, wheat bran and a diet denominated aged food. Except wheat bran for L. intermedia, all diets provided adequate development for both species, which showed that any of them can be used in laboratory insectaries for these insects. L. intermedia showed better development with most nutritious diets and both species presented better development with aged food. Fungi as an additional nutrient source for L. intermedia and L. longipalpis is suggested.

[Discriminating concentrations for three insecticides used in public health in a Lutzomyia longipalpis experimental strain from Colombia].

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Marceló, Catalina; Cabrera, Olga Lucía; Santamaría, Erika

2014-01-01

In Colombia, periurban populations of Lutzomyia longipalpis , vector of the causative agent of visceral leishmaniasis in the upper and middle valley of the Magdalena River, may be exposed to insecticide applications with different purposes. Thus, it is important to begin a susceptibility surveillance of this species to insecticides. To determine indicators of susceptibility to three insecticides habitually used in public health, such as malathion, deltamethrin and lambda-cyhalothrin in an experimental strain of L. longipalpis . We used the method proposed by the Centers for Disease Control and Prevention. Groups of 10 to 15 unfed females were exposed to different concentrations of the insecticides using 250 ml glass bottles as test chambers. Mortality was registered every five minutes for an hour. Diagnostic concentrations and lethal times for each insecticide were calculated. In the evaluated L. longipalpis strain, the diagnostic concentrations and times were 75 µg/ml and 25 minutes for malathion, 10 µg/ml and 35 minutes for deltamethrin, and 15 µg/ml during 30 minutes for lambda-cyhalothrin. Baseline data over mortality response to three insecticides were established in a susceptibility strain of L. longipalpis vector. These indicators will allow establishing comparisons with populations of L. longipalpis exposed regularly or sporadically to chemical control measures to detect changes in their resistance to these insecticides.

Presence of Lutzomyia longipalpis (Diptera: Psychodidae) in the Parque Estadual da Serra da Tiririca, State of Rio de Janeiro, Southeastern Brazil.

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Fuzari, Andressa Alencastre; Delmondes, Aline Ferreira Dos Santos; Barbosa, Vanessa De Araújo; Marra, Francisco de Assis; Brazil, Reginaldo Peçanha

2016-01-01

The sand fly, Lutzomyia longipalpis, is the main vector of Leishmania infantum in the Americas, primarily occurring in areas of apparent anthropomorphic modifications in several regions of Brazil. Sand flies were captured using light traps. Out of all captured species, Lu. longipalpis numbers had increased within the park. We report the occurrence of Lu. longipalpis in an area of Atlantic Forest, possibly representing the first sylvatic population of Lu. longipalpis in an area absent of peridomestic captures, but with the risk of L. infantum transmission in the areas of Niterói and Maricá.

Identification of the sex pheromone of Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera: Psychodidae from Asunción, Paraguay

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Caballero Norath

2009-11-01

Full Text Available Abstract The sand fly Lutzomyia longipalpis is the main vector of Leishmania (L. infantum (Nicolle, the causative agent of American visceral leishmaniasis (AVL in the New World. Male Lu. longipalpis have secretory glands which produce sex pheromones in either abdominal tergites 4 or 3 and 4. These glands are sites of sex pheromone production and each pheromone type may represent true sibling species. In Latin America, apart from Lu. pseudolongipalpis Arrivillaga and Feliciangeli from Venezuela, populations of Lu. longipalpis s.l. can be identified by their male-produced sex pheromones: (S-9-methylgermacrene-B, 3-methyl-α-himachalene and the two cembrenes, 1 and 2. In this study, we present the results of a coupled gas chromatography - mass spectrometry analysis of the pheromones of males Lu. longipalpis captured in an endemic area of visceral leishmaniasis in Asunción, Paraguay. Our results show that Lu. longipalpis from this site produce (S-9-methylgermacrene-B which has also been found in Lu. longipalpis from different areas of Brazil, Colombia and Central America.

Identification of the sex pheromone of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae) from Asunción, Paraguay

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Brazil, Reginaldo P; Caballero, Norath Natalia; Hamilton, James Gordon C

2009-01-01

The sand fly Lutzomyia longipalpis is the main vector of Leishmania (L.) infantum (Nicolle), the causative agent of American visceral leishmaniasis (AVL) in the New World. Male Lu. longipalpis have secretory glands which produce sex pheromones in either abdominal tergites 4 or 3 and 4. These glands are sites of sex pheromone production and each pheromone type may represent true sibling species. In Latin America, apart from Lu. pseudolongipalpis Arrivillaga and Feliciangeli from Venezuela, populations of Lu. longipalpis s.l. can be identified by their male-produced sex pheromones: (S)-9-methylgermacrene-B, 3-methyl-α-himachalene and the two cembrenes, 1 and 2. In this study, we present the results of a coupled gas chromatography - mass spectrometry analysis of the pheromones of males Lu. longipalpis captured in an endemic area of visceral leishmaniasis in Asunción, Paraguay. Our results show that Lu. longipalpis from this site produce (S)-9-methylgermacrene-B which has also been found in Lu. longipalpis from different areas of Brazil, Colombia and Central America. PMID:19883505

Identification of the sex pheromone of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae) from Asunción, Paraguay.

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Brazil, Reginaldo P; Caballero, Norath Natalia; Hamilton, James Gordon C

2009-11-02

The sand fly Lutzomyia longipalpis is the main vector of Leishmania (L.) infantum (Nicolle), the causative agent of American visceral leishmaniasis (AVL) in the New World. Male Lu. longipalpis have secretory glands which produce sex pheromones in either abdominal tergites 4 or 3 and 4. These glands are sites of sex pheromone production and each pheromone type may represent true sibling species. In Latin America, apart from Lu. pseudolongipalpis Arrivillaga and Feliciangeli from Venezuela, populations of Lu. longipalpis s.l. can be identified by their male-produced sex pheromones: (S)-9-methylgermacrene-B, 3-methyl-alpha-himachalene and the two cembrenes, 1 and 2.In this study, we present the results of a coupled gas chromatography - mass spectrometry analysis of the pheromones of males Lu. longipalpis captured in an endemic area of visceral leishmaniasis in Asunción, Paraguay. Our results show that Lu. longipalpis from this site produce (S)-9-methylgermacrene-B which has also been found in Lu. longipalpis from different areas of Brazil, Colombia and Central America.

Ecological parameters of the (S)-9-methylgermacrene-B population of the Lutzomyia longipalpis complex in a visceral leishmaniasis area in São Paulo state, Brazil.

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Galvis-Ovallos, Fredy; Casanova, Claudio; Sevá, Anaiá da Paixão; Galati, Eunice Aparecida Bianchi

2017-05-30

Visceral leishmaniasis (VL) is an important public health challenge in Brazil because of the high number of human and canine cases reported annually. Leishmania infantum is the etiological agent of VL and Lutzomyia longipalpis is its main vector. However, evidence suggests that this taxon constitutes a species complex. In Sao Paulo state, there are two populations of Lu. longipalpis, each secreting distinct pheromones, (S)-9-methylgermacrene-B and Cembrene 1; both have been associated with different patterns of VL transmission. The aim of the present study was to investigate the temporal distribution and natural infection of the (S)-9-methylgermacrene-B population of the Lu. longipalpis complex in a highly VL endemic area of Sao Paulo state to obtain information that may contribute to the surveillance of this zoonosis and to the planning of preventive and control measures. The study was carried out in Panorama municipality, Sao Paulo State. Captures were made during 24 months in seven domiciles. The relation between sand fly abundance and climatic variables, temperature and humidity, was analyzed and natural infection by Leishmania spp. in sand fly females was investigated by nested PCR. A total of 4120 sand flies, with predominance of Lu. longipalpis (97.2%) were captured. The highest averages of sand flies/night/trap occurred in the rainy season (November-March) and a positive, significant correlation between sand fly abundance and the temperature and humidity 20 days before the capture days was found. Leishmania infantum DNA was detected in three out of 250 pools of females analyzed, giving an estimated minimum infection rate of 1.2%. The identification of the climatic association between the high abundance of the vector in this highly endemic VL focus constitutes a fundamental point for evaluating future vector and dog control measures and this information increases the data of VL foci in Sao Paulo state that could contribute to the public health authorities

Abundance of Lutzomyia longipalpis in urban households as risk factor of transmission of visceral leishmaniasis.

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Vianna, Elisa Neves; Morais, Maria Helena Franco; Almeida, Andréa Sobral de; Sabroza, Paulo Chagastelles; Reis, Ilka Afonso; Dias, Edelberto Santos; Carneiro, Mariângela

2016-05-01

Urban occurrence of human and canine visceral leishmaniasis (VL) is linked to households with characteristics conducive to the presence of sand flies. This study proposes an ad hoc classification of households according to the environmental characteristics of receptivity to phlebotominae and an entomological study to validate the proposal. Here we describe the phlebotominae population found in intra- and peridomiciliary environments and analyse the spatiotemporal distribution of the VL vector Lutzomyia longipalpis of households receptive to VL. In the region, 153 households were classified into levels of receptivity to VL followed by entomological surveys in 40 of those properties. Kruskal-Wallis verified the relationship between the households' classification and sand fly abundance and Kernel analysis evaluated L. longipalpis spatial distribution: of the 740 sand flies were captured, 91% were L. longipalpis; 82% were found peridomiciliary whilst the remaining 18% were found intradomiciliary. No statistically significant association was found between sandflies and households levels. L. longipalpis counts were concentrated in areas of high vulnerability and some specific households were responsible for the persistence of the infestation. L. longipalpis prevails over other sand fly species for urban VL transmission. The entomological study may help target the surveillance and vector control strategies to domiciles initiating and/or maintaining VL outbreaks.

Sandfly Lutzomyia longipalpis in a Cutaneous leishmaniasis focus in central Colombia.

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López, Y; Osorio, L; Alvarez, G; Rojas, J; Jiménez, F; Gómez, C; Ferro, C

1996-01-01

Lutzomyia longipalpis, 15 other species of the genus Lutzomyia, and one species of Brumptomyia were collected in an endemic focus of cutaneous leishmaniasis in a river canyon 450 m above sea-level, in Rio Claro, Antioquia, Colombia. The presence of Lu. longipalpis is associated with the destruction of the primary forest and the development of new farmland and rural settlement in this region. The composition of species identified a different habitat for Lu. longipalpis in Colombia. Lu. yuilli and Lu. longipalpis were predominant (68.26%) followed by Lu. trapidoi, Lu. hartmani, Lu. triramula, Lu. panamensis, Lu. gomezi.

Spatial population dynamics and temporal analysis of the distribution of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae) in the city of Clorinda, Formosa, Argentina.

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Gómez-Bravo, Andrea; German, Alba; Abril, Marcelo; Scavuzzo, Marcelo; Salomón, Oscar D

2017-07-25

Lutzomyia longipalpis, the vector for the causal agent of visceral leishmaniasis (VL), has extended its distribution in the southern cone in the Americas. The first urban record of Lu. longipalpis in Argentina was from the City of Clorinda in 2004. The aim of this study was to analyse the monthly distribution and abundance of Lu. longipalpis and to evaluate its association with environmental and climatic variables in Clorinda City, Province of Formosa. Phlebotominae sampling was performed using CDC light mini-traps that were placed in different sites of the city between January 2012 and December 2013. Environmental variables including the normalised difference vegetation index, normalized difference water index, land surface temperature and precipitation were evaluated using a spatiotemporal model. A total of 4996 phlebotomine sandflies were captured during the study period, and eight species were reported: Lu. longipalpis, Migonemyia migonei, Nyssomyia whitmani, Ny. neivai, Brumptomyia guimaraesi, Evandromyia cortelezzii/sallesi, Psathyromyia bigeniculata and Expapillata firmatoi. This is the first urban record of Ex. firmatoi in Argentina. Lutzomyia longipalpis was the most abundant species between 2012 and 2013, and it appeared in all the sampled sites. Moreover, the model applied showed that ground humidity and temperature were significantly associated with the abundance of Lu. longipalpis. This longitudinal approach at city scale allows for modelling that explains more than 60% of the temporal variability of the abundance of Lu. longipalpis based exclusively on satellite obtained data. The results support the hypothesis of steady 'hot spots' of abundance with time, while other sites could change its abundance due to eventual microenvironment changes. The Lu. longipalpis abundance driving factors are breeding site-related variables, highlighting the importance both for modelling and surveillance to use lag data.

Fixed differences in the paralytic gene define two lineages within the Lutzomyia longipalpis complex producing different types of courtship songs.

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Rachel M M A Lins

Full Text Available The sand fly Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae, the most important vector of American visceral leishmaniasis, is widely distributed in Latin America. There is currently a consensus that it represents a species complex, however, the number and distribution of the different siblings is still uncertain. Previous analyses have indicated that Brazilian populations of this vector can be divided into two main groups according to the type of courtship song (Burst vs. Pulse males produce during copulation. Nevertheless, no diagnostic differences have been observed between these two groups with most molecular markers used to date. We analyzed the molecular divergence in a fragment of the paralytic (para gene, a locus involved in the control of courtship songs in Drosophila, among a number of Lu. longipalpis populations from Brazil producing Burst and Pulse-type songs. Our results revealed a very high level of divergence and fixed differences between populations producing the two types of songs. We also compared Lu. longipalpis with a very closely related species, Lutzomyia cruzi, which produces Burst-type songs. The results indicated a higher number of fixed differences between Lu. cruzi and the Pulse-type populations of Lu. longipalpis than with those producing Burst-type songs. The data confirmed our previous assumptions that the presence of different sibling species of the Lu. longipalpis complex in Brazil can be divided into two main groups, one representing a single species and a second more heterogeneous group that probably represents a number of incipient species. We hypothesize that para might be one of the genes directly involved in the control of the courtship song differences between these two groups or that it is linked to other loci associated with reproductive isolation of the Brazilian species.

Fixed Differences in the paralytic Gene Define Two Lineages within the Lutzomyia longipalpis Complex Producing Different Types of Courtship Songs

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Lins, Rachel M. M. A.; Souza, Nataly A.; Brazil, Reginaldo P.; Maingon, Rhayza D. C.; Peixoto, Alexandre A.

2012-01-01

The sand fly Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae), the most important vector of American visceral leishmaniasis, is widely distributed in Latin America. There is currently a consensus that it represents a species complex, however, the number and distribution of the different siblings is still uncertain. Previous analyses have indicated that Brazilian populations of this vector can be divided into two main groups according to the type of courtship song (Burst vs. Pulse) males produce during copulation. Nevertheless, no diagnostic differences have been observed between these two groups with most molecular markers used to date. We analyzed the molecular divergence in a fragment of the paralytic (para) gene, a locus involved in the control of courtship songs in Drosophila, among a number of Lu. longipalpis populations from Brazil producing Burst and Pulse-type songs. Our results revealed a very high level of divergence and fixed differences between populations producing the two types of songs. We also compared Lu. longipalpis with a very closely related species, Lutzomyia cruzi, which produces Burst-type songs. The results indicated a higher number of fixed differences between Lu. cruzi and the Pulse-type populations of Lu. longipalpis than with those producing Burst-type songs. The data confirmed our previous assumptions that the presence of different sibling species of the Lu. longipalpis complex in Brazil can be divided into two main groups, one representing a single species and a second more heterogeneous group that probably represents a number of incipient species. We hypothesize that para might be one of the genes directly involved in the control of the courtship song differences between these two groups or that it is linked to other loci associated with reproductive isolation of the Brazilian species. PMID:22970200

The first record of Lutzomyia longipalpis in the Argentine northwest

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Andrea Gomez Bravo

2013-12-01

Full Text Available In 2004, the urban presence of Lutzomyia longipalpis was recorded for the first time in Formosa province. In 2006, the first autochthonous case of human urban visceral leishmaniasis (VL was recorded in Misiones in the presence of the vector, along with some canine VL cases. After this first case, the vector began to spread primarily in northeast Argentina. Between 2008-2011, three human VL cases were reported in Salta province, but the presence of Lu. longipalpis was not recorded. Captures of Phlebotominae were made in Tartagal, Salta, in 2013, and the presence of Lu. longipalpis was first recorded in northwest Argentina at that time. Systematic sampling is recommended to observe the distribution and dispersion patterns of Lu. longipalpis and consider the risk of VL transmission in the region.

Seasonal abundance 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; Devlin, B; Wilson, M L; Tesh, R B

1995-07-01

Ecological studies on the sand fly Lutzomyia longipalpis (Lutz & Neiva) were conducted during 1990-1993 in a small rural community in Colombia where American visceral leishmaniasis is endemic. Standardized weekly sand fly collections made from pigpens and natural resting sites displayed a bimodal annual abundance cycle, with a small peak occurring in October-November and a larger one in April-May. Time series analysis was employed to quantify the associations between sand fly abundance and weather factors (temperature, relative humidity, and rainfall). In addition to a prominent 6-mo cycle. Fourier analysis of the collection data demonstrated that the L. longipalpis population also exhibited a 5- to 8-wk cycle that may represent the length of larval development. Autoregressive moving average models were fit to weekly collection data and their residuals were regressed against rainfall, temperature, and relative humidity. A significant positive association between female L. longipalpis abundance and the relative humidity and rainfall recorded 3 wk earlier was found, indicating that these factors may be of value in predicting sand fly abundance. Additionally, these data indicated that L. longipalpis larvae may become quiescent during adverse conditions.

Differential application of lambda-cyhalothrin to control the sandfly Lutzomyia longipalpis.

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Kelly, D W; Mustafa, Z; Dye, C

1997-01-01

To study the impact of residual pyrethroid insecticide on the abundance and distribution of peridomestic Lutzomyia longipalpis, the sandfly vector of visceral leishmaniasis in Brazil, lambda-cyhalothrin was applied at 20 mg a.i.m-2 in the following interventions: (i) spraying of all animal pens in a village (blanket coverage); (ii) treatment of a subset of animal pens, either by spraying, or by installation of insecticide-impregnated 1 m2 cotton sheets as 'targets' (focal coverage). By sampling with CDC light traps, and using a novel analytical approach, we detected a 90% reduction in Lu.longipalpis abundance in sprayed sheds of the focal intervention. However, there was no discernible effect on the abundance of other phlebotomines trapped in sheds, or on the abundance of Lu.longipalpis in untreated dining-huts and houses. This differential impact on Lu.longipalpis abundance is explained in terms of the disruption of male pheromone production. Treated targets were approximately half as effective as residual spraying in reducing the abundance of Lu.longipalpis in sheds. Following blanket intervention, the abundance of Lu.longipalpis in traps fell by only 45% (not significant): catches at untreated dining-huts actually increased, possibly because the blanket coverage diverted Lu.longipalpis away from major aggregation sites at animal pens. It is recommended that care be taken during vector control programmes to ensure that all potential aggregation sites are treated. The possible consequences of leaving some sites untreated include poor control of peridomestic sandfly abundance and an increase in the biting rate on dogs and humans.

Phenotypic differentiation in love song traits among sibling species of the Lutzomyia longipalpis complex in Brazil.

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Vigoder, Felipe M; Souza, Nataly A; Brazil, Reginaldo P; Bruno, Rafaela V; Costa, Pietra L; Ritchie, Michael G; Klaczko, Louis B; Peixoto, Alexandre A

2015-05-28

Brazilian populations of Lutzomyia longipalpis may constitute a complex of cryptic species, and this report investigates the distribution and number of potential sibling species. One of the main differences observed among Brazilian populations is the type of acoustic signal produced by males during copulation. These copulation song differences seem to be evolving faster than neutral molecular markers and have been suggested to contribute to insemination failure observed in crosses between these sibling species. In previous studies, two main types of copulation songs were found, burst-type and pulse-type. The latter type can, in turn, be further subdivided into five different patterns. We recorded male song from 13 new populations of the L. longipalpis complex from Brazil and compared the songs with 12 already available. Out of these 25 populations, 16 produce burst-type and 9 produce pulse-type songs. We performed a principal component analysis in these two main groups separately and an additional discriminant analysis in the pulse-type group. The pulse-type populations showed a clear separation between the five known patterns with a high correspondence of individuals to their correct group, confirming the differentiation between them. The distinctiveness of the burst-type subgroups was much lower than that observed among the pulse-type groups and no clear population structure was observed. This suggests that the burst-type populations represent a single species. Overall, our results are consistent with the existence in Brazil of at least six species of the L. longipalpis complex, one with a wide distribution comprising all the populations with burst-type songs, and five more closely related allopatric siblings with different pulse-type song patterns and more restricted distribution ranges.

Synthetic sex pheromone attracts the leishmaniasis vector Lutzomyia longipalpis (Diptera: Psychodidae) to traps in the field.

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Bray, D P; Bandi, K K; Brazil, R P; Oliveira, A G; Hamilton, J G C

2009-05-01

Improving vector control remains a key goal in reducing the world's burden of infectious diseases. More cost-effective approaches to vector control are urgently needed, particularly because vaccines are unavailable and treatment is prohibitively expensive. The causative agent of American visceral leishmaniasis (AVL), Leishmania chagasi, Cunha and Chagas (Kinetoplastida: Trypanosomatidae), is transmitted between animal and human hosts by blood-feeding female sand flies attracted to mating aggregations formed on or above host animals by male-produced sex pheromones. Our results show the potential of using synthetic pheromones to control populations of Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae), the sand fly vector of one of the world's most important neglected diseases, AVL. We showed that a synthetic pheromone, (+/-)-9-methylgermacrene-B, produced from a low-cost plant intermediate, attracted females in the laboratory. By formulating dispensers that released this pheromone at a rate similar to that released by aggregating males, we were able to attract flies of both sexes to traps in the field. These dispensers worked equally well when deployed with mechanical light traps and inexpensive sticky traps. If deployed effectively, pheromone-based traps could be used to decrease AVL transmission rates through specific targeting and reduction of L. longipalpis populations. This is the first study to show attraction of a human disease-transmitting insect to a synthetic pheromone in the field, showing the general applicability of this novel approach for developing new tools for use in vector control.

Synthetic Sex Pheromone Attracts the Leishmaniasis Vector Lutzomyia longipalpis (Diptera: Psychodidae) to Traps in the Field

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Bray, D. P.; Bandi, K. K.; Brazil, R. P.; Oliveira, A. G.; Hamilton, J.G.C.

2011-01-01

Improving vector control remains a key goal in reducing the world’s burden of infectious diseases. More cost-effective approaches to vector control are urgently needed, particularly as vaccines are unavailable and treatment is prohibitively expensive. The causative agent of AVL, Leishmania chagasi, Cunha and Chagas (Kinetoplastida: Trypanosomatidae) is transmitted between animal and human hosts by blood-feeding female sand flies, attracted to mating aggregations formed on or above host animals by male-produced sex pheromones. Our results demonstrate the potential of using synthetic pheromones to control populations of Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae), the sand fly vector of one of the world’s most important neglected diseases, American visceral leishmaniasis (AVL). We showed that a synthetic pheromone, (±)-9-methylgermacrene-B, produced from a low-cost plant intermediate, attracted females in the laboratory. Then by formulating dispensers that released this pheromone at a rate similar to that released by aggregating males, we were able to attract flies of both sexes to traps in the field. These dispensers worked equally well when deployed with mechanical light traps and inexpensive sticky traps. If deployed effectively, pheromone-based traps could be used to decrease AVL transmission rates through specific targeting and reduction of L. longipalpis populations. This is the first study to show attraction of a human disease-transmitting insect to a synthetic pheromone in the field, demonstrating the general applicability of this novel approach for developing new tools for use in vector control. PMID:19496409

Wing geometry as a tool for studying the Lutzomyia longipalpis (Diptera: Psychodidae complex

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J De la Riva

2001-11-01

Full Text Available Toro Toro (T and Yungas (Y have been described as genetically well differentiated populations of the Lutzomyia longipalpis (Lutz & Neiva, 1912 complex in Bolivia. Here we use geometric morphometrics to compare samples from these populations and new populations (Bolivia and Nicaragua, representing distant geographical origins, qualitative morphological variation ("one-spot" or "two-spots" phenotypes, ecologically distinct traits (peridomestic and silvatic populations, and possibly different epidemiological roles (transmitting or nor transmitting Leishmania chagasi. The Nicaragua (N (Somotillo sample was "one-spot" phenotype and a possible peridomestic vector. The Bolivian sample of the Y was also "one-spot" phenotype and a demonstrated peridomestic vector of visceral leishmaniasis (VL. The three remaining samples were silvatic, "two-spots" phenotypes. Two of them (Uyuni and T were collected in the highlands of Bolivian where VL never has been reported. The last one (Robore, R came from the lowlands of Bolivia, where human cases of VL are sporadically reported. The decomposition of metric variation into size and shape by geometric morphometric techniques suggests the existence of two groups (N/Y/R, and U/T. Several arguments indicate that such subdivision of Lu. longipalpis could correspond to different evolutionary units.

The status of the Lutzomyia longipalpis species complex and possible implications for Leishmania transmission

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Uribe Sandra

1999-01-01

Full Text Available The sand fly Lutzomyia longipalpis sensu latu has been identified as the principal vector of American visceral leishmaniasis, a potentially fatal disease that primarily affects children in several countries of South and Central America. Over the past several years increases have occurred both in the number of reported cases and the population at risk: approximately 1.6 million people reside in highly endemic areas with 16,000 cases reported annually. Several studies have attempted to relate the epidemiology of this disease to variability in Lu. longipalpis that is now recognized to be a complex of at least three sibling species. Morphological variation in this species was first noted by Mangabeira (1969. Since then physiological and biochemical differences have been reported by several investigators. Recent reports in Costa Rica of the presence of Lu. longipalpis in a focus of cutaneous leishmaniasis caused by Leishmania chagasi may be an additional indication of variability in this species. While existing evidence indicates that the morphospecies Lu. longipalpis may represent a complex of sibling species, genetic, epidemiological and ecological distinctions have not been fully resolved. Thus, delimitation of systematic boundaries within the complex and corresponding to geographic distributions and roles in transmission remain unresolved. The purpose of this review is to summarize from the literature observations of polymorphism in this morphospecies and consider what significance this reported variability may have to the epidemiology of visceral leishmaniasis.

Lutzomyia longipalpis urbanisation and control

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Oscar Daniel Salomón

2015-11-01

Full Text Available Since the description of Lutzomyia longipalpis by Lutz and Neiva more than 100 years ago, much has been written in the scientific literature about this phlebotomine species. Soares and Turco (2003 and Lainson and Rangel (2005 have written extensive reviews focused on vector-host-parasite interactions and American visceral leishmaniasis ecology. However, during the last two decades, the success of Lu. longipalpis in colonising urban environments and its simultaneous geographical spreading have led to new theoretical and operational questions. Therefore, this review updates the general information about this species and notes the more challenging topics regarding the new scenario of urbanisation-spreading and its control in America. Here, we summarise the literature on these issues and the remaining unsolved questions, which pose recommendations for operational research.

Lutzomyia longipalpis urbanisation and control

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Salomón, Oscar Daniel; Feliciangeli, María Dora; Quintana, María Gabriela; Afonso, Margarete Martins dos Santos; Rangel, Elizabeth Ferreira

2015-01-01

Since the description of Lutzomyia longipalpis by Lutz and Neiva more than 100 years ago, much has been written in the scientific literature about this phlebotomine species. Soares and Turco (2003) and Lainson and Rangel (2005) have written extensive reviews focused on vector-host-parasite interactions and American visceral leishmaniasis ecology. However, during the last two decades, the success of Lu. longipalpis in colonising urban environments and its simultaneous geographical spreading have led to new theoretical and operational questions. Therefore, this review updates the general information about this species and notes the more challenging topics regarding the new scenario of urbanisation-spreading and its control in America. Here, we summarise the literature on these issues and the remaining unsolved questions, which pose recommendations for operational research. PMID:26517497

Antissaliva Antibodies of Lutzomyia Longipalpis in area of Visceral Leishmaniasis.

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Fraga, Thiago Leite; Fernandes, Magda Freitas; Pontes, Elenir Rose Jardim Cury; Levay, Ana Paula Silva; Almeida da Cunha, Elenice Brandão; França, Adriana de Oliveira; Dorval, Maria Elizabeth Cavalheiros

2016-07-01

The aim of the present study was to assess the presence of antissaliva antibodies of Lutzomyia longipalpis in human hosts living in area of visceral leishmaniasis, located in the Center-West region of Brazil. The presence of antissaliva antibodies of L. longipalpis exhibited a strong correlation with the protection and development of antibodies against Leishmania sp. Of the 492 children studied, elevated antissaliva antibodies of L. longipalpis were detected in 38.4% of the participants. There was a higher percentage of positivity (64.7%) among children who exhibited anti-Leishmania sp. antibodies and among those who were positive in the delayed hypersensitivity test (34.8%).

Lovesongs and period gene polymorphisms indicate Lutzomyia cruzi (Mangabeira, 1938) as a sibling species of the Lutzomyia longipalpis (Lutz and Neiva, 1912) complex.

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Vigoder, Felipe M; Araki, Alejandra S; Bauzer, Luiz G S R; Souza, Nataly A; Brazil, Reginaldo P; Peixoto, Alexandre A

2010-08-01

The sand fly Lutzomyia cruzi (Mangabeira, 1938) is implicated as a vector of American visceral leishmaniasis (AVL) in some areas of Brazil. Lutzomyia cruzi is closely related to Lutzomyia longipalpis s.l. (Lutz and Neiva, 1912) the main Latin American vector of AVL and a species complex. Although females of the two species are identical, the males can be distinguished by differences in the genitalia. Nevertheless, pheromone analysis shows that Lu. cruzi males produce 9-methyl-germacrene-B, which has also been found in a number of Latin American populations of Lu. longipalpis s.l. In addition, analysis of microsatellite loci shows that the level of divergence between Lu. cruzi and Lu. longipalpis s.l. is similar to that observed among the Lu. longipalpis s.l. sibling species. Here we present the lovesongs of Lu. cruzi males which are similar to the Burst-type songs produced by one of the Lu. longipalpis s.l. sibling species. We also present data on the molecular polymorphisms of the period gene of Lu. cruzi that indicate this species as another sibling within the Lu. longipalpis complex. The results highlight the importance of an integrative approach to understand the patterns of genetic and phenotypic divergence among very closely related vector species. Copyright 2010. Published by Elsevier B.V.

Ecology of Lutzomyia longipalpis and Lutzomyia migonei in an endemic area for visceral leishmaniasis.

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Silva, Rafaella Albuquerque; Santos, Fabricio Kassio Moura; Sousa, Lindemberg Caranha de; Rangel, Elizabeth Ferreira; Bevilaqua, Claudia Maria Leal

2014-01-01

The main vector for visceral leishmaniasis (VL) in Brazil is Lutzomyia longipalpis. However, the absence of L. longipalpis in a region of autochthonous VL demonstrates the participation of other species in the transmission of the parasite. Studies conducted in La Banda, Argentina, and São Vicente Férrer, Pernambuco State, Brazil, have correlated the absence of L. longipalpis and the presence of L. migonei with autochthonous cases of VL. In São Vicente Férrer, Pernambuco, there was evidence for the natural infection of L. migonei with Leishmania infantum chagasi. Thus, the objective of this work was to assess the ecology of the sand flies L. longipalpis and L. migonei in Fortaleza, an endemic area for VL. Insect capture was conducted at 22 sampling points distributed across four regions of Fortaleza. In total, 32,403 sand flies were captured; of these, 18,166 (56%) were identified as L. longipalpis and 14,237 (44%) as L. migonei. There were significant density differences found between the vectors at each sampling site (indoors and outdoors) (p longipalpis are distributed throughout Fortaleza, where they have adapted to an indoor environment, and suggest that L. migonei may share the role as a vector with L. longipalpis in the transmission of VL in Fortaleza.

Characterization of a midgut mucin-like glycoconjugate of Lutzomyia longipalpis with a potential role in Leishmania attachment.

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Myšková, Jitka; Dostálová, Anna; Pěničková, Lucie; Halada, Petr; Bates, Paul A; Volf, Petr

2016-07-25

Leishmania parasites are transmitted by phlebotomine sand flies and a crucial step in their life-cycle is the binding to the sand fly midgut. Laboratory studies on sand fly competence to Leishmania parasites suggest that the sand flies fall into two groups: several species are termed "specific/restricted" vectors that support the development of one Leishmania species only, while the others belong to so-called "permissive" vectors susceptible to a wide range of Leishmania species. In a previous study we revealed a correlation between specificity vs permissivity of the vector and glycosylation of its midgut proteins. Lutzomyia longipalpis and other four permissive species tested possessed O-linked glycoproteins whereas none were detected in three specific vectors examined. We used a combination of biochemical, molecular and parasitological approaches to characterize biochemical and biological properties of O-linked glycoprotein of Lu. longipalpis. Lectin blotting and mass spectrometry revealed that this molecule with an apparent molecular weight about 45-50 kDa corresponds to a putative 19 kDa protein with unknown function detected in a midgut cDNA library of Lu. longipalpis. We produced a recombinant glycoprotein rLuloG with molecular weight around 45 kDa. Anti-rLuloG antibodies localize the native glycoprotein on epithelial midgut surface of Lu. longipalpis. Although we could not prove involvement of LuloG in Leishmania attachment by blocking the native protein with anti-rLuloG during sand fly infections, we demonstrated strong binding of rLuloG to whole surface of Leishmania promastigotes. We characterized a novel O-glycoprotein from sand fly Lutzomyia longipalpis. It has mucin-like properties and is localized on the luminal side of the midgut epithelium. Recombinant form of the protein binds to Leishmania parasites in vitro. We propose a role of this molecule in Leishmania attachment to sand fly midgut.

Behavioral aspects of Lutzomyia longipalpis (Diptera: Psychodidae) in urban area endemic for visceral leishmaniasis.

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De Oliveira, E F; Silva, E A; Casaril, A E; Fernandes, C E S; Paranhos Filho, A C; Gamarra, R M; Ribeiro, A A; Brazil, R P; Oliveira, A G

2013-03-01

The study of some of the behavioral aspects of the main vector of Leishmania infantum chagasi Cunha & Chagas in the Americas, Lutzomyia longipalpis (Lutz & Neiva), such as dispersion, population size, and vector survival rates, is important for the elucidation of the mechanisms of visceral leishmaniasis transmission. These parameters were studied by means of capture-mark-release-recapture experiments in an urban area of Campo Grande municipality, an endemic area of visceral leishmaniasis, situated in Mato Grosso do Sul state, Brazil. Six capture-mark-release-recapture experiments were undertaken between November 2009 and November 2010 and once in January 2012 with a view to assessing the population size and survival rate of Lu. longipalpis. The insects were released in a peridomicile surrounded by 13 residences. The recaptures were undertaken with automatic light traps for four consecutive weeks after release in the surrounding area. In total, 3,354 sand flies were captured, marked, and released. The overall recapture rate during the capture-mark-release-recapture experiments was 4.23%, of which 92.45% were recaptured at the release site, indicating limited dispersal. The greatest distance recorded from the release site was 165 m for males and 241 m for females. The male daily survival rate, calculated on the basis of regressions from the numbers of marked recaptured insects during the 15 successive days after release was 0.897. The estimated male population size measured by the Lincoln Index was 10,947.127. Though Lu. longipalpis presented a limited dispersion the physical barriers typical of urban environments did not prevent the sand flies from flying long distances.

Studies on the Feeding Habits of Lutzomyia (Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera: Psychodidae: Phlebotominae Populations from Endemic Areas of American Visceral Leishmaniasis in Northeastern Brazil

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Margarete Martins dos Santos Afonso

2012-01-01

Full Text Available The aim of this study was to identify potential blood feeding sources of L. (L. longipalpis specimens from populations in Northeastern Brazil, endemic areas of American Visceral Leishmaniasis (AVL and its correlation with the transmission of L. (L. i. chagasi. The ELISA technique was applied using bird, dog, goat, opossum, equine, feline, human, sheep, and rodent antisera to analyze 609 females, resulting in an overall positivity of 60%. In all municipalities, females showed higher positivity for bird followed by dog antiserum and sand fly specimens were also positive for equine, feline, human, sheep, goat, opossum, and rodent antisera. The finding for 17 combinations of two or three types of blood in some females corroborates the opportunistic habit of this sand fly species. The results demonstrating the association between L. (L. longipalpis and opossum suggest the need for further evaluation of the real role of this synanthropic mammal in the eco-epidemiology of AVL.

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.

Expression of the mevalonate pathway enzymes in the Lutzomyia longipalpis (Diptera: Psychodidae) sex pheromone gland demonstrated by an integrated proteomic approach.

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González-Caballero, Natalia; Rodríguez-Vega, Andrés; Dias-Lopes, Geovane; Valenzuela, Jesus G; Ribeiro, Jose M C; Carvalho, Paulo Costa; Valente, Richard H; Brazil, Reginaldo P; Cuervo, Patricia

2014-01-16

In Latin America, Lutzomyia longipalpis is the main vector of the protozoan parasite Leishmania infantum, which is the causal agent of American Visceral Leishmaniasis. This insect uses male-produced pheromones for mate recognition. Elucidation of pheromone biogenesis or its regulation may enable molecular strategies for mating disruption and, consequently, the vector's population management. Motivated by our recent results of the transcriptomic characterization of the L. longipalpis pheromone gland, we performed a proteomic analysis of this tissue combining SDS-PAGE, and mass spectrometry followed by an integrative data analysis. Considering that annotated genome sequences of this sand fly are not available, we designed an alternative workflow searching MS/MS data against two customized databases using three search engines: Mascot, OMSSA and ProLuCID. A total of 542 proteins were confidently characterized, 445 of them using a Uniref100-insect protein database, and 97 using a transcript translated database. In addition, use of PEAKS for de novo peptide sequencing of MS/MS data confirmed ~90% identifications made with the combination of the three search engines. Our results include the identification of six of the seven enzymes of the mevalonate-pathway, plus the enzymes involved in sesquiterpenoid biosynthesis, all of which are proposed to be involved in pheromone production in L. longipalpis. L. longipalpis is the main vector of the protozoan parasite L. infantum, which is the causal agent of American Visceral Leishmaniasis. One of the control measures of such disease is focused on vector population control. As this insect uses male-produced pheromones for mate recognition, the elucidation of pheromone biogenesis or its regulating process may enable molecular strategies for mating disruption and, consequently, this vector's population management. On this regard, in this manuscript we report expression evidence, at the protein level, of several molecules potentially

Distribución de Lutzomyia longipalpis en la Mesopotamia Argentina, 2010 Distribution of Lutzomyia longipalpis in the Argentine Mesopotamia, 2010

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Oscar D. Salomón

2011-02-01

Full Text Available El primer caso autóctono de leishmaniasis visceral (LV en la Argentina se notificó en el año 2006 en Posadas, Misiones, y en el verano 2008-2009 se comprobó la dispersión del vector de LV, Lutzomyia longipalpis y casos de LV canina en la provincia de Corrientes. Para conocer la distribución del riesgo, entre febrero y marzo del 2010 se realizó la búsqueda sistemática del vector de LV en 18 localidades de las provincias de Entre Ríos, Corrientes y en la ciudad de Puerto Iguazú, Misiones, totalizando 313 trampas/noche. Se comprobó la presencia de Lu. longipalpis, por primera vez, en las localidades de Chajarí (Entre Ríos, Alvear, La Cruz, Curuzú Cuatiá y Bella Vista (Corrientes, y en Puerto Iguazú (Misiones. En Santo Tomé y Monte Caseros (Corrientes se volvió a registrar la presencia del vector, y se obtuvieron las trampas con más ejemplares, 830 y 126 Lu. longipalpis trampa/sitio/noche respectivamente. Los resultados muestran que el vector de la LV urbana, continúa dispersándose en el territorio argentino. Simultáneamente, la propagación del parásito, y los consecuentes casos de LV humana se asocian al aumento de reservorios, perros infectados con o sin clínica, debidos al tránsito humano.The first case of visceral leishmaniasis (VL in Argentina was reported in 2006 in Posadas, Misiones. During the summer 2008-2009 Lutzomyia longipalpis, the VL vector, and canine VL cases were already spread along the province of Corrientes. In order to know the distribution of VL risk, systematic captures of the vector were performed between February and March 2010, in 18 areas of the provinces of Entre Ríos and Corrientes, and the city of Puerto Iguazú, Misiones, with a total of 313 traps/night. We confirmed the presence of Lu. longipalpis, for the first time in Chajarí (Entre Ríos, Alvear, La Cruz, Curuzú Cuatiá and Bella Vista (Corrientes, and Puerto Iguazú (Misiones. In Santo Tome and Monte Caseros (Corrientes, where the

Seasonal variation of Lutzomyia longipalpis in Belo Horizonte, State of Minas Gerais

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Resende Marcelo Carvalho de

2006-01-01

Full Text Available Between October, 1997 and September, 1999 in Belo Horizonte, Minas Gerais a study of seasonal variation of Lutzomyia longipalpis was carried out in three distinct areas of the municipality. Sand flies were sampled at 15-day intervals in three residences, in each of which two CDC light traps were installed, one indoors and the other in the peridomicile. A total of 397 sand flies were captured in the three areas, with 65%, 30% and 1% of specimens collected in the eastern, northeast and Barreiro districts, respectively. The overall proportions of sand flies collected inside and around the houses were similar (57% vs 43% and this pattern was seen for both Lutzomyia longipalpis and Lutzomyia whitmani . The highest population levels during the two years of the study were from October to March. From October onwards, numbers increased constantly until February. A gradual fall was seen from April onwards until the lowest levels were reached in the months of June, July and August.

Genetic divergence between two sympatric species of the Lutzomyia longipalpis complex in the paralytic gene, a locus associated with insecticide resistance and lovesong production

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RMMA Lins

2008-11-01

Full Text Available The sandfly Lutzomyia longipalpis s.l. is the main vector of American Visceral Leishmaniasis. L. longipalpis s.l. is a species complex but until recently the existence of cryptic sibling species among Brazilian populations was a controversial issue. A fragment of paralytic (para, a voltage dependent sodium channel gene associated with insecticide resistance and courtship song production in Drosophila, was isolated and used as a molecular marker to study the divergence between two sympatric siblings of the L. longipalpis complex from Sobral, Brazil. The results revealed para as the first single locus DNA marker presenting fixed differences between the two species in this locality. In addition, two low frequency amino-acid changes in an otherwise very conserved region of the channel were observed, raising the possibility that it might be associated with incipient resistance in this vector. To the best of our knowledge, the present study represents the first population genetics analysis of insecticide resistance genes in this important leishmaniasis vector.

Control trial of Lutzomyia longipalpis s.l. in the Island of Margarita, Venezuela.

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Feliciangeli, M Dora; Mazzarri, Milena B; Blas, Sonia San; Zerpa, Olga

2003-12-01

The incidence of the American visceral leishmaniasis (AVL) in the Island of Margarita, a major tourist centre in Venezuela, has been increasing between 1998 and 2001. Lutzomyia longipalpis s.l. is the recognized vector, which was found naturally infected with Leishmania spp, indistinguishable from the parasites recovered from dogs and children. In 1999-2000, we conducted a control trial in Santa Ana del Valle and Las Cabreras, which have similar epidemiological and ecological conditions. The trial was based on intradomestic residual spraying of lambda-cyhalothrin, E.C., 25 mg/m2 and spatial fogging of fenitrothion around the houses at 30 g/ha. Sandfly abundance was recorded using Centers for Disease Control (CDC) traps indoors and outdoors. We found significantly reduced sandfly populations in the target locality. Wall bioassays showed that the residual effect of the insecticide lasts for about 3 months. We believe that indoor spraying with lambda-cyhalothrin three times a year, at a dose slightly greater than 25 mg/m2, might reduce the L. longipalpis s.l. population to a level low enough for achieving a significant reduction of the indoor transmission, thus protecting small children from the disease.

Leishmania infantum Genetic Diversity and Lutzomyia longipalpis Mitochondrial Haplotypes in Brazil

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Ribolla, Paulo Eduardo Martins; Gushi, Letícia Tsieme; Pires e Cruz, Maria do Socorro; Costa, Carlos Henrique Nery; Costa, Dorcas Lamounier; Lima Júnior, Manoel Sebastião da Costa; Dorval, Maria Elizabeth Moraes Cavalheiros; Gutierrez de Oliveira, Alessandra; da Cunha Santos, Mirella Ferreira; Fonseca Camargo-Neves, Vera Lúcia; Fortaleza, Carlos Magno Castello Branco; Alonso, Diego Peres

2016-01-01

Leishmania infantum is the etiological agent of visceral leishmaniasis (VL) in the Americas with domestic dogs being its major reservoir hosts. The main VL vector is the sandfly Lutzomyia longipalpis, while other Lutzomyia species may play a role in disease transmission. Although the genetic structure of L. infantum populations has been widely evaluated, only a few studies have addressed this subject coupled to the genetic structure of the respective sandfly vectors. In this study, we analyze...

Larval breeding sites of Lutzomyia longipalpis (Diptera: Psychodidae) in visceral leishmaniasis endemic urban areas in Southeastern Brazil.

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Casanova, Cláudio; Andrighetti, Maria T M; Sampaio, Susy M P; Marcoris, Maria L G; Colla-Jacques, Fernanda E; Prado, Angelo P

2013-01-01

The scarcity of information on the immature stages of sand flies and their preferred breeding sites has resulted in the focus of vectorial control on the adult stage using residual insecticide house-spraying. This strategy, along with the treatment of human cases and the euthanasia of infected dogs, has proven inefficient and visceral leishmaniasis continues to expand in Brazil. Identifying the breeding sites of sand flies is essential to the understanding of the vector's population dynamic and could be used to develop novel control strategies. In the present study, an intensive search for the breeding sites of Lutzomyia longipalpis was conducted in urban and peri-urban areas of two municipalities, Promissão and Dracena, which are endemic for visceral leishmaniasis in São Paulo State, Brazil. During an exploratory period, a total of 962 soil emergence traps were used to investigate possible peridomiciliary breeding site microhabitats such as: leaf litter under tree, chicken sheds, other animal sheds and uncovered debris. A total of 160 sand flies were collected and 148 (92.5%) were L. longipalpis. In Promissão the proportion of chicken sheds positive was significantly higher than in leaf litter under trees. Chicken shed microhabitats presented the highest density of L. longipalpis in both municipalities: 17.29 and 5.71 individuals per square meter sampled in Promissão and Dracena respectively. A contagious spatial distribution pattern of L. longipalpis was identified in the emergence traps located in the chicken sheds. The results indicate that chicken sheds are the preferential breeding site for L. longipalpis in the present study areas. Thus, control measures targeting the immature stages in chicken sheds could have a great effect on reducing the number of adult flies and consequently the transmission rate of Leishmania (Leishmania) infantum chagasi.

Canine antibody response to Lutzomyia longipalpis saliva in endemic area of visceral leishmaniasis.

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Batista, Luís Fábio da Silva; Matta, Vânia Lúcia Ribeiro da; Tomokane, Thaise Yumie; Pacheco, Acácio Duarte; Silveira, Fernando Tobias; Rossi, Claudio Nazaretian; Marcondes, Mary; Laurenti, Márcia Dalastra

2016-01-01

Canine exposure to Lutzomyia longipalpis bites and the potential of Leishmania infantum transmissibility for the vector were evaluated. Immunoglobulin G (IgG) anti-Lu longipalpis saliva and -L. infantum, and blood parasite load were determined in dogs from endemic areas of visceral leishmaniasis. Blood parasitism was similar between symptomatic and asymptomatic dogs. IgG anti-L. infantum was higher in symptomatic dogs, but IgG anti-Lu. longipalpis saliva was mostly observed in higher titers in asymptomatic dogs, indicating vector preference for feeding on asymptomatic dogs. Our data suggest a pivotal role of asymptomatic dogs in L. infantum transmission in endemic areas.

Prostaglandin E2/leukotriene B4 balance induced by Lutzomyia longipalpis saliva favors Leishmania infantum infection.

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Araújo-Santos, Théo; Prates, Deboraci Brito; França-Costa, Jaqueline; Luz, Nívea F; Andrade, Bruno B; Miranda, José Carlos; Brodskyn, Claudia I; Barral, Aldina; Bozza, Patrícia T; Borges, Valéria Matos

2014-12-20

Eicosanoids and sand fly saliva have a critical role in the Leishmania infection. Here, we evaluated the effect of Lutzomyia longipalpis salivary gland sonicate (SGS) on neutrophil and monocyte recruitment and activation of eicosanoid production in a murine model of inflammation. C57BL/6 mice were inoculated intraperitonealy with Lutzomyia longipalpis SGS or Leishmania infantum or both, followed by analyses of cell recruitment, parasite load and eicosanoid production. Intraperitoneal injection of Lutzomyia longipalpis SGS together with Leishmania infantum induced an early increased parasite viability in monocytes and neutrophils. L. longipalpis SGS increased prostaglandin E2 (PGE2), but reduced leukotriene B4 (LTB4) production ex vivo in peritoneal leukocytes. In addition, the pharmacological inhibition of cyclooxygenase 2 (COX-2) with NS-398 decreased parasite viability inside macrophages during Leishmania infection in the presence of L. longipalpis SGS arguing that PGE2 production is associated with diminished parasite killing. These findings indicate that L. longipalpis SGS is a critical factor driving immune evasion of Leishmania through modulation of PGE2/LTB4 axis, which may represent an important mechanism on establishment of the infection.

Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae: a review

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Rodrigo P. P. Soares

2003-09-01

Full Text Available Lutzomyia longipalpis is the most important vector of AmericanVisceral Leishmaniasis (AVL due to Leishmania chagasi in the New World. Despite its importance, AVL, a disease primarily of rural areas, has increased its prevalence and became urbanized in some large cities in Brazil and other countries in Latin America. Although the disease is treatable, other control measures include elimination of infected dogs and the use of insecticides to kill the sand flies. A better understanding of vector biology could also account as one more tool for AVL control. A wide variety of papers about L. longipalpis have been published in the recent past years. This review summarizes our current information of this particular sand fly regarding its importance, biology, morphology, pheromones genetics, saliva, gut physiology and parasite interactions.

Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae: a review

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Soares Rodrigo P. P.

2003-01-01

Full Text Available Lutzomyia longipalpis is the most important vector of AmericanVisceral Leishmaniasis (AVL due to Leishmania chagasi in the New World. Despite its importance, AVL, a disease primarily of rural areas, has increased its prevalence and became urbanized in some large cities in Brazil and other countries in Latin America. Although the disease is treatable, other control measures include elimination of infected dogs and the use of insecticides to kill the sand flies. A better understanding of vector biology could also account as one more tool for AVL control. A wide variety of papers about L. longipalpis have been published in the recent past years. This review summarizes our current information of this particular sand fly regarding its importance, biology, morphology, pheromones genetics, saliva, gut physiology and parasite interactions.

Lutzomyia longipalpis and the eco-epidemiology of American visceral leishmaniasis, with particular reference to Brazil: a review

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Ralph Lainson

2005-12-01

Full Text Available An historical review is given of American visceral leishmaniasis (AVL, with particular reference to the eco-epidemiology of the disease in Brazil. Following the first records of AVL in this country, in 1934, the sandfly Lutzomyia longipalpis (Lutz and Neiva, 1912 was incriminated as the principal vector. It is now generally accepted, however, that there exist a number of cryptic species under the name of Lu. longipalpis s.l. and that variations in the quantity of the vasodilatory peptide maxadilan in the saliva of flies from different populations of Lu. longipalpis s.l., may account for the variable clinical manifestations of AVL seen in different geographic regions. Distribution of AVL has been shown to extend throughout most of South and Central America, with the domestic dog serving as the principal reservoir of infection for man. However, while one hypothesis suggests that the causative parasite is Leishmania infantum, imported from Europe with the Portuguese and Spanish colonists, the demonstration of a high rate of benign, inapparent infection in foxes in Amazonian Brazil raised an opposing suggestion that the parasite is indigenous to the Americas. Recent reports of similar infections in native marsupials, and possibly rodents, tend to support this view, particularly as Lu. longipalpis is primordially a silvatic sandfly. Although effective control measures in foci of the disease will diminish the number of canine and human infections, the presence of such an enzootic in a variety of native animals will render the total eradication of AVL unlikely.

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

Spatial and temporal changes in Lutzomyia longipalpis abundance, a Leishmania infantum vector in an urban area in northeastern Argentina.

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Fernández, María Soledad; Santini, María Soledad; Cavia, Regino; Sandoval, Adolfo Enrique; Pérez, Adriana Alicia; Acardi, Soraya; Salomón, Oscar Daniel

2013-11-01

This study aimed to analyse changes in the spatial distribution of Lutzomyia longipalpis in Posadas, an urban area located in northeastern Argentina. Data were obtained during the summer of 2007 and 2009 through two entomological surveys of peridomiciles distributed around the city. The abundance distribution pattern for 2009 was computed and compared with the previous pattern obtained in 2007, when the first human visceral leishmaniasis cases were reported in the city. Vector abundance was also examined in relation to micro and macrohabitat characteristics. In 2007 and 2009, Lu. longipalpis was distributed among 41.5% and 31% of the households in the study area, respectively. In both years, the abundance rates at most of the trapping sites were below 30 Lu. longipalpis per trap per night; however, for areas exhibiting 30-60 Lu. longipalpis and more than 60 Lu. longipalpis, the areas increased in both size and number from 2007-2009. Lu. longipalpis was more abundant in areas with a higher tree and bush cover (a macrohabitat characteristic) and in peridomiciles with accumulated unused material (a microhabitat characteristic). These results will help to prioritise and focus control efforts by defining which peridomiciles display a potentially high abundance of Lu. longipalpis.

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

Serological tests fail to discriminate dogs with visceral leishmaniasis that transmit Leishmania infantum to the vector Lutzomyia longipalpis.

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Mendonça, Ivete Lopes de; Batista, Joilson Ferreira; Werneck, Guilherme Loureiro; Soares, Maria Regiane Araújo; Costa, Dorcas Lamounier; Costa, Carlos Henrique Nery

2017-01-01

The control of reservoirs for Leishmania infantum -induced zoonotic visceral leishmaniasis requires the identification of dogs posing a population risk. Here, we assessed the performance of several assays to identify Lutzomyia longipalpis infectious dogs. We evaluated 99 dogs that were positive for visceral leishmaniasis based on parasite identification. Serological analyses were performed using an enzyme-linked immunosorbent assay, immunofluorescence antibody tests in 1:40 and 1:80 dilutions, rapid dual path platform tests, immunochromatographic assay with a recombinant rK39 antigen, fast agglutination screening tests, and direct agglutination tests. We also performed PCR to analyze peripheral blood and xenodiagnosis. Forty-six dogs infected at least one L. longipalpis specimen. Although the serological test sensitivities were above 85% for detecting L. longipalpis infectious dogs, none showed a satisfactory performance, as both specificity (0.06 to 13%) and the area under the receiver operating characteristic curve (45 to 53%) were low. The PCR results were also weak, with a sensitivity of 30%, specificity of 72%, and an area under the receiver operating characteristic curve of 51%. The infected L. longipalpis proportion was higher among asymptomatic dogs than symptomatic dogs. Among the symptomatic dogs, those with ulceration-free skin diseases were more infectious, with an odds ratio of 9.3 (confidence interval of 1.10 - 428.5). The larger the number of insects fed, the greater the detected infectiousness. Our study supports the imperative to develop novel technologies for identifying the infectious dogs that transmit L. infantum for the benefit of public health.

Spatial and temporal changes in Lutzomyia longipalpis abundance, a Leishmania infantum vector in an urban area in northeastern Argentina

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Fernández, María Soledad; Santini, María Soledad; Cavia, Regino; Sandoval, Adolfo Enrique; Pérez, Adriana Alicia; Acardi, Soraya; Salomón, Oscar Daniel

2013-01-01

This study aimed to analyse changes in the spatial distribution of Lutzomyia longipalpis in Posadas, an urban area located in northeastern Argentina. Data were obtained during the summer of 2007 and 2009 through two entomological surveys of peridomiciles distributed around the city. The abundance distribution pattern for 2009 was computed and compared with the previous pattern obtained in 2007, when the first human visceral leishmaniasis cases were reported in the city. Vector abundance was also examined in relation to micro and macrohabitat characteristics. In 2007 and 2009, Lu. longipalpis was distributed among 41.5% and 31% of the households in the study area, respectively. In both years, the abundance rates at most of the trapping sites were below 30 Lu. longipalpis per trap per night; however, for areas exhibiting 30-60 Lu. longipalpis and more than 60 Lu. longipalpis, the areas increased in both size and number from 2007-2009. Lu. longipalpis was more abundant in areas with a higher tree and bush cover (a macrohabitat characteristic) and in peridomiciles with accumulated unused material (a microhabitat characteristic). These results will help to prioritise and focus control efforts by defining which peridomiciles display a potentially high abundance of Lu. longipalpis. PMID:24271040

Spatial and temporal changes in Lutzomyia longipalpis abundance, a Leishmania infantum vector in an urban area in northeastern Argentina

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Maria Soledad Fernandez

2013-11-01

Full Text Available This study aimed to analyse changes in the spatial distribution of Lutzomyia longipalpis in Posadas, an urban area located in northeastern Argentina. Data were obtained during the summer of 2007 and 2009 through two entomological surveys of peridomiciles distributed around the city. The abundance distribution pattern for 2009 was computed and compared with the previous pattern obtained in 2007, when the first human visceral leishmaniasis cases were reported in the city. Vector abundance was also examined in relation to micro and macrohabitat characteristics. In 2007 and 2009, Lu. longipalpis was distributed among 41.5% and 31% of the households in the study area, respectively. In both years, the abundance rates at most of the trapping sites were below 30 Lu. longipalpis per trap per night; however, for areas exhibiting 30-60 Lu. longipalpis and more than 60 Lu. longipalpis, the areas increased in both size and number from 2007-2009. Lu. longipalpis was more abundant in areas with a higher tree and bush cover (a macrohabitat characteristic and in peridomiciles with accumulated unused material (a microhabitat characteristic. These results will help to prioritise and focus control efforts by defining which peridomiciles display a potentially high abundance of Lu. longipalpis.

Genetic differentiation in natural populations of Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae) with different phenotypic spot patterns on tergites in males.

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Silva, M H; Nascimento, M D S B; Leonardo, F S; Rebêlo, J M M; Pereira, S R F

2011-01-01

Entomological surveys in the state of Maranhão have recorded morphologically distinct populations of Lutzomyia longipalpis (Lutz & Neiva). Some populations have one pair of spots (1S) on the fourth tergite, while others have two pairs (2S) on the third and fourth tergites of males. In the present study we investigated the degree of genetic polymorphism among four populations in the municipalities of Caxias, Codó and Raposa, in the state of Maranhão, Brazil, by using RAPD (Random Amplified Polymorphic DNA) markers. A total of 35 loci were identified, of which 30 were polymorphic. The highest polymorphism was observed with primer OPA 4, which produced 11 different profiles. Genetic diversity was assessed using grouping methods that produced a dendrogram in which the genotypes could be clearly separated into two main clades according to the number of spots on the male abdominal tergites. One cluster contained the populations from Caxias and Codó, and the other was formed by the populations from Raposa and Codó. The results of our RAPD analysis showed a clear separation between the populations with one and two pairs of spots. The epidemiologic significance of this genetic differentiation should be investigated in future studies.

American visceral leishmaniasis dissociated from Lutzomyia longipalpis (Diptera, Psychodidae) in the State of Espírito Santo, Brazil.

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Pinto, Israel de Souza; Santos, Claudiney Biral dos; Grimaldi, Gabriel; Ferreira, Adelson Luiz; Falqueto, Aloísio

2010-02-01

The occurrence of American visceral leishmaniasis in the State of Espírito Santo, Brazil has always been associated with the presence of the Lutzomyia longipalpis vector. The geographic distribution of this vector in this state is related to the presence of specific geoclimatic characteristics, such as a dry climate, low elevations (longipalpis. Sand flies were captured monthly from July 2006 to August 2007 using Shannon and CDC traps in two municipalities with records of autochthonous American visceral leishmaniasis and one with no record. We captured 13,112 sand flies, but no Lu. longipalpis was found. The absence of Lu. longipalpis and the possible role of another American visceral leishmaniasis vector in these localities were discussed.

Anomalies in the sand fly Lutzomyia longipalpis (Diptera: Psychodidae) in Brazil.

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Sanguinette, Cristiani de Castilho; Faustino, Juliana Xavier; Serra e Meira, Paula Cavalcante Lamy; Botelho, Helbert Antônio; Carvalho, Gustavo Mayr de Lima; Gontijo, Célia Maria Ferreira; Filho, José Dilermando Andrade

2013-03-01

Lutzomyia longipalpis is the main species involved in the epidemiological cycle of visceral leishmaniasis in Brazil. This species shows a wide geographic distribution and belongs to a group that has 2 setae in the paramere with the curved tips towards the apex of this structure among other characteristics. Morphological characters in the genitalia of phlebotomines are essential for correct identification of species. The aim of this study was to report the finding of unilateral and bilateral anomalies in the paramere of L. longipalpis males collected in Várzea da Palma municipality, Minas Gerais State, Brazil. Twelve collections were made during the period April 2009 to March 2010, using Centers for Disease Control and Prevention light traps, HP model. Of the 8,832 male L. longipalpis collected, we found 6 types of unilateral anomalies and 2 types of bilateral anomalies in 0.5% of the insects collected. The anomalies were described according to number, position, and size of the setae of paramere. This information will be useful in the validation of new species.

Relationship between digestive enzymes and food habit of Lutzomyia longipalpis (Diptera: Psychodidae) larvae: Characterization of carbohydrases and digestion of microorganisms.

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Moraes, C S; Lucena, S A; Moreira, B H S; Brazil, R P; Gontijo, N F; Genta, F A

2012-08-01

The sandfly Lutzomyia longipalpis (Lutz and Neiva, 1912) is the main vector of American Visceral Leishmaniasis. In spite of its medical importance and several studies concerning adult digestive physiology, biochemistry and molecular biology, very few studies have been carried out to elucidate the digestion in sandfly larvae. Even the breeding sites and food sources of these animals in the field are largely uncharacterized. In this paper, we describe and characterize several carbohydrases from the gut of L. longipalpis larvae, and show that they are probably not acquired from food. The enzyme profile of this insect is consistent with the digestion of fungal and bacterial cells, which were proved to be ingested by larvae under laboratory conditions. In this respect, sandfly larvae might have a detritivore habit in nature, being able to exploit microorganisms usually encountered in the detritus as a food source. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bacterial feeding, Leishmania infection and distinct infection routes induce differential defensin expression in Lutzomyia longipalpis.

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Telleria, Erich L; Sant'Anna, Maurício R Viana; Alkurbi, Mohammad O; Pitaluga, André N; Dillon, Rod J; Traub-Csekö, Yara M

2013-01-11

Phlebotomine insects harbor bacterial, viral and parasitic pathogens that can cause diseases of public health importance. Lutzomyia longipalpis is the main vector of visceral leishmaniasis in the New World. Insects can mount a powerful innate immune response to pathogens. Defensin peptides take part in this response and are known to be active against Gram-positive and Gram-negative bacteria, and some parasites. We studied the expression of a defensin gene from Lutzomyia longipalpis to understand its role in sand fly immune response. We identified, sequenced and evaluated the expression of a L. longipalpis defensin gene by semi-quantitative RT-PCR. The gene sequence was compared to other vectors defensins and expression was determined along developmental stages and after exposure of adult female L. longipalpis to bacteria and Leishmania. Phylogenetic analysis showed that the L. longipalpis defensin is closely related to a defensin from the Old World sand fly Phlebotomus duboscqi. Expression was high in late L4 larvae and pupae in comparison to early larval stages and newly emerged flies. Defensin expression was modulated by oral infection with bacteria. The Gram-positive Micrococcus luteus induced early high defensin expression, whilst the Gram-negative entomopathogenic Serratia marcescens induced a later response. Bacterial injection also induced defensin expression in adult insects. Female sand flies infected orally with Leishmania mexicana showed no significant difference in defensin expression compared to blood fed insects apart from a lower defensin expression 5 days post Leishmania infection. When Leishmania was introduced into the hemolymph by injection there was no induction of defensin expression until 72 h later. Our results suggest that L. longipalpis modulates defensin expression upon bacterial and Leishmania infection, with patterns of expression that are distinct among bacterial species and routes of infection.

Fine structure and distribution pattern of antennal sensilla of Lutzomyia longipalpis (Diptera: Psychodidae) sand flies.

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Fernandes, Fernando de Freitas; Bahia-Nascimento, Ana Cristina; Pinto, Luciana Conceição; Leal, Cynthia de Sousa; Secundino, Nágila Francinete Costa; Pimenta, Paulo Filemon Paolucci

2008-11-01

The specific aims of this work were to examine the antennal sensilla of Lutzomyia longipalpis (Lutz & Neiva 1912) (Diptera: Psychodidae) adults and to characterize their typology and topography, with special attention to olfactory sensilla. The surfaces of the antennal segments of Lu. longipalpis males and females were studied by scanning electron microscopy (SEM). Lu. longipalpis used in the current study were obtained from a colony originating from Lapinha Cave, Minas Gerais state, Brazil. Microtrichiae and 11 subtypes of sensilla were observed and characterized according to the following categories: five subtypes of trichoid sensilla (short, medium, long blunt-tipped, long pointed-tipped, and apical), two coeloconic sensilla (grooved and praying hands), and campaniform, chaetic, basiconic, and squamiform sensilla. SEM analyses showed few differences between males and females in the typology, topography, and quantity of antennal sensilla described. The current study is the first to identify several categories of antennal sensilla of the genus Lutzomyia and their distribution patterns. The identification of these sensillar types may be important in planning future electrophysiological studies to develop alternative measures of control and monitoring of Lu. longipalpis.

The transcriptome of Lutzomyia longipalpis (Diptera: Psychodidae) male reproductive organs.

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Azevedo, Renata V D M; Dias, Denise B S; Bretãs, Jorge A C; Mazzoni, Camila J; Souza, Nataly A; Albano, Rodolpho M; Wagner, Glauber; Davila, Alberto M R; Peixoto, Alexandre A

2012-01-01

It has been suggested that genes involved in the reproductive biology of insect disease vectors are potential targets for future alternative methods of control. Little is known about the molecular biology of reproduction in phlebotomine sand flies and there is no information available concerning genes that are expressed in male reproductive organs of Lutzomyia longipalpis, the main vector of American visceral leishmaniasis and a species complex. We generated 2678 high quality ESTs ("Expressed Sequence Tags") of L. longipalpis male reproductive organs that were grouped in 1391 non-redundant sequences (1136 singlets and 255 clusters). BLAST analysis revealed that only 57% of these sequences share similarity with a L. longipalpis female EST database. Although no more than 36% of the non-redundant sequences showed similarity to protein sequences deposited in databases, more than half of them presented the best-match hits with mosquito genes. Gene ontology analysis identified subsets of genes involved in biological processes such as protein biosynthesis and DNA replication, which are probably associated with spermatogenesis. A number of non-redundant sequences were also identified as putative male reproductive gland proteins (mRGPs), also known as male accessory gland protein genes (Acps). The transcriptome analysis of L. longipalpis male reproductive organs is one step further in the study of the molecular basis of the reproductive biology of this important species complex. It has allowed the identification of genes potentially involved in spermatogenesis as well as putative mRGPs sequences, which have been studied in many insect species because of their effects on female post-mating behavior and physiology and their potential role in sexual selection and speciation. These data open a number of new avenues for further research in the molecular and evolutionary reproductive biology of sand flies.

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.

Effects of azadirachtin on the biology of Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) adult female, the main vector of American visceral leishmaniasis.

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De Andrade-Coelho, Cláudia Alves; De Souza, Nataly Araujo; Silva, Vanderlei Campos; Souza, Adelson A; Gonzalez, Marcelo Salabert; Rangel, Elizabeth Ferreira

2014-07-01

The effects of azadirachtin A added to the sucrose diet of the adult females on the mortality, oviposition, and hatching of the sand fly vector of American visceral leishmaniasis Lutzomyia longipalpis (Lutz & Neiva, 1912) were investigated. Concentrations of 0.1, 1.0, and 10.0 microg/mg of azadirachtin significantly increased insect mortality in comparison with control insects. The same dose also significantly reduced oviposition but not hatching. After a long development period, significantly fewer adult insects were obtained from eggs hatching by azadirachtin-treated females in a dose-response manner. These results indicate that azadirachtin is a potent sterilizer that could be used against the development of Lu. longipalpis populations and as a tool for studying physiological and biochemical processes in phlebotomine species.

Alternative splicing originates different domain structure organization of Lutzomyia longipalpis chitinases.

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Ortigão-Farias, João Ramalho; Di-Blasi, Tatiana; Telleria, Erich Loza; Andorinho, Ana Carolina; Lemos-Silva, Thais; Ramalho-Ortigão, Marcelo; Tempone, Antônio Jorge; Traub-Csekö, Yara Maria

2018-02-01

BACKGROUND The insect chitinase gene family is composed by more than 10 paralogs, which can codify proteins with different domain structures. In Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Brazil, a chitinase cDNA from adult female insects was previously characterized. The predicted protein contains one catalytic domain and one chitin-binding domain (CBD). The expression of this gene coincided with the end of blood digestion indicating a putative role in peritrophic matrix degradation. OBJECTIVES To determine the occurrence of alternative splicing in chitinases of L. longipalpis. METHODS We sequenced the LlChit1 gene from a genomic clone and the three spliced forms obtained by reverse transcription polymerase chain reaction (RT-PCR) using larvae cDNA. FINDINGS We showed that LlChit1 from L. longipalpis immature forms undergoes alternative splicing. The spliced form corresponding to the adult cDNA was named LlChit1A and the two larvae specific transcripts were named LlChit1B and LlChit1C. The B and C forms possess stop codons interrupting the translation of the CBD. The A form is present in adult females post blood meal, L4 larvae and pre-pupae, while the other two forms are present only in L4 larvae and disappear just before pupation. Two bands of the expected size were identified by Western blot only in L4 larvae. MAIN CONCLUSIONS We show for the first time alternative splicing generating chitinases with different domain structures increasing our understanding on the finely regulated digestion physiology and shedding light on a potential target for controlling L. longipalpis larval development.

The current status of the Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) species complex.

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Souza, Nataly A; Brazil, Reginaldo P; Araki, Alejandra S

2017-03-01

Lutzomyia longipalpis s.l. is a complex of sibling species and is the principal vector of American visceral leishmaniasis. The present review summarises the diversity of efforts that have been undertaken to elucidate the number of unnamed species in this species complex and the phylogenetic relationships among them. A wide variety of evidence, including chemical, behavioral and molecular traits, suggests very recent speciation events and complex population structure in this group. Although significant advances have been achieved to date, differential vector capacity and the correlation between structure of parasite and vector populations have yet to be elucidated. Furthermore, increased knowledge about recent epidemiological changes, such as urbanisation, is essential for pursuing effective strategies for sandfly control in the New World.

Lutzomyia longipalpis saliva or salivary protein LJM19 protects against Leishmania braziliensis and the saliva of its vector, Lutzomyia intermedia.

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Natalia M Tavares

Full Text Available BACKGROUND: Leishmania transmission occurs in the presence of insect saliva. Immunity to Phlebotomus papatasi or Lutzomyia longipalpis saliva or salivary components confers protection against an infection by Leishmania in the presence of the homologous saliva. However, immunization with Lutzomyia intermedia saliva did not protect mice against Leishmania braziliensis plus Lu. intermedia saliva. In the present study, we have studied whether the immunization with Lu. longipalpis saliva or a DNA plasmid coding for LJM19 salivary protein would be protective against L. braziliensis infection in the presence of Lu. intermedia saliva, the natural vector for L. braziliensis. METHODOLOGY/PRINCIPAL FINDINGS: Immunization with Lu. longipalpis saliva or with LJM19 DNA plasmid induced a Delayed-Type Hypersensitivity (DTH response against Lu. longipalpis as well as against a Lu. intermedia saliva challenge. Immunized and unimmunized control hamsters were then intradermally infected in the ears with L. braziliensis in the presence of Lu. longipalpis or Lu. intermedia saliva. Animals immunized with Lu. longipalpis saliva exhibited smaller lesion sizes as well as reduced disease burdens both at lesion site and in the draining lymph nodes. These alterations were associated with a significant decrease in the expression levels of IL-10 and TGF-β. Animals immunized with LJM19 DNA plasmid presented similar findings in protection and immune response and additionally increased IFN-γ expression. CONCLUSIONS/SIGNIFICANCE: Immunization with Lu. longipalpis saliva or with a DNA plasmid coding LJM19 salivary protein induced protection in hamsters challenged with L. braziliensis plus Lu. intermedia saliva. These findings point out an important role of immune response against saliva components, suggesting the possibility to develop a vaccine using a single component of Lu. longipalpis saliva to generate protection against different species of Leishmania, even those

Occurrence and Probability Maps of Lutzomyia longipalpis and Lutzomyia cruzi (Diptera: Psychodidae: Phlebotominae) in Brazil.

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Andrade-Filho, J D; Scholte, R G C; Amaral, A L G; Shimabukuro, P H F; Carvalho, O S; Caldeira, R L

2017-09-01

Leishmaniases are serious diseases caused by trypanosomatid protozoans of the genus Leishmania transmitted by the bite of phlebotomine sand flies. We analyzed records pertaining to Lutzomyia longipalpis (Lutz and Neiva, 1912) and Lutzomyia cruzi (Mangabeira, 1938) in Brazil from the following sources: the collection of phlebotomine sand flies of the Centro de Pesquisas René Rachou/Fiocruz (FIOCRUZ-COLFLEB), the "SpeciesLink" (CRIA) database, from systematic surveys of scientific articles and gray literature (dissertations, theses, and communications), and disease data obtained from the Information System for Notifiable Diseases/Ministry of Health (SINAN/MS). Environmental data and ecological niche modeling (ESMS) using the approach of MaxEnt algorithm produced maps of occurrence probability for both Lu. longipalpis and Lu. cruzi. Lutzomyia longipalpis was found in 229 Brazilian municipalities and Lu. cruzi in 27. The species were sympatric in 16 municipalities of the Central-West region of Brazil. Our results show that Lu. longipalpis is widely distributed and associated with the high number of cases of visceral leishmaniasis reported in Brazil. © 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.

Report of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae) in a cutaneous-leishmaniasis-endemic area of Panama.

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Valderrama, Anayansi; Tavares, Mara Garcia; Andrade Filho, José Dilermando

2011-12-01

Lutzomyia longipalpis is the primary vector of the parasite responsible for visceral leishmaniasis in the Americas. In the present study, Lu. longipalpis was found in a domiciliary area in Limón, a district in Capira, a region in which cutaneous leishmaniasis is endemic in Panama. Previously, this species has been found in a humid forest in this same region. Finding Lu. longipalpis in domiciliary areas indicates that this species may be adapting to new habitats and that it may play a role in the transmission of leishmaniasis in Panama.

Predicting the geographic distribution of Lutzomyia longipalpis (Diptera: Psychodidae) and visceral leishmaniasis in the state of Mato Grosso do Sul, Brazil.

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Almeida, Paulo Silva de; Sciamarelli, Alan; Batista, Paulo Mira; Ferreira, Ademar Dimas; Nascimento, João; Raizer, Josué; Andrade Filho, José Dilermando; Gurgel-Gonçalves, Rodrigo

2013-12-01

To understand the geographic distribution of visceral leishmaniasis (VL) in the state of Mato Grosso do Sul (MS), Brazil, both the climatic niches of Lutzomyia longipalpis and VL cases were analysed. Distributional data were obtained from 55 of the 79 counties of MS between 2003-2012. Ecological niche models (ENM) of Lu. longipalpis and VL cases were produced using the maximum entropy algorithm based on eight climatic variables. Lu. longipalpis showed a wide distribution in MS. The highest climatic suitability for Lu. longipalpis was observed in southern MS. Temperature seasonality and annual mean precipitation were the variables that most influenced these models. Two areas of high climatic suitability for the occurrence of VL cases were predicted: one near Aquidauana and another encompassing several municipalities in the southeast region of MS. As expected, a large overlap between the models for Lu. longipalpis and VL cases was detected. Northern and northwestern areas of MS were suitable for the occurrence of cases, but did not show high climatic suitability for Lu. longipalpis. ENM of vectors and human cases provided a greater understanding of the geographic distribution of VL in MS, which can be applied to the development of future surveillance strategies.

Association of Lutzomyia longipalpis (Diptera: Psychodidae) population density with climate variables in Montes Claros, an area of American visceral leishmaniasis transmission in the state of Minas Gerais, Brazil.

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Michalsky, Erika Monteiro; Fortes-Dias, Consuelo Latorre; França-Silva, João Carlos; Rocha, Marilia Fonseca; Barata, Ricardo Andrade; Dias, Edelberto Santos

2009-12-01

In the present paper, we evaluate the relationship between climate variables and population density of Lutzomyia longipalpis in Montes Claros, an area of active transmission of American visceral leishmaniasis (AVL) in Brazil. Entomological captures were performed in 10 selected districts of the city, between September 2002-August 2003. A total of 773 specimens of L. longipalpiswere captured in the period and the population density could be associated with local climate variables (cumulative rainfall, average temperature and relative humidity) through a mathematical linear model with a determination coefficient (Rsqr) of 0.752. Although based on an oversimplified statistical analysis, as far as the vector is concerned, this approach showed to be potentially useful as a starting point to guide control measures for AVL in Montes Claros.

Comparative vectorial efficiency of Lutzomyia evansi and Lu. longipalpis for transmitting Leishmania chagasi.

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Montoya-Lerma, J; Cadena, H; Oviedo, M; Ready, P D; Barazarte, R; Travi, B L; Lane, R P

2003-01-01

The infection rates and development of Leishmania chagasi in two sandfly species, Lutzomyia evansi and Lutzomyia longipalpis, were evaluated under natural and experimental conditions. Natural infection rates of Lu. evansi in San Andrés de Sotavento (Colombia) and Montañas de Peraza (Venezuela) (0.05 and 0.2%, respectively) were similar to those previously recorded for this species in Colombia and Venezuela and for Lu. longipalpis in many foci of American Visceral Leishmaniasis (AVL). Both sand fly species were able to support the development of two Colombian strains of L. chagasi experimentally acquired from dogs, hamsters or membrane feeders. However, the experimental infection rates and the sequence of parasite development in the guts of these sand flies revealed that parasite colonisation, differentiation, migration and attachment were more frequent and uniform in Lu. longipalpis than in Lu. evansi. This is consistent with a more recent association between L. chagasi and Lu. evansi, and these results might help to explain the irregularity of AVL outbreaks in foci where Lu. evansi has been reported as the sole vector. Copyright 2002 Elsevier Science B.V.

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.

Association of Lutzomyia longipalpis (Diptera: Psychodidae population density with climate variables in Montes Claros, an area of American visceral leishmaniasis transmission in the state of Minas Gerais, Brazil

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Érika Monteiro Michalsky

2009-12-01

Full Text Available In the present paper, we evaluate the relationship between climate variables and population density of Lutzomyia longipalpis in Montes Claros, an area of active transmission of American visceral leishmaniasis (AVL in Brazil. Entomological captures were performed in 10 selected districts of the city, between September 2002-August 2003. A total of 773 specimens of L. longipalpiswere captured in the period and the population density could be associated with local climate variables (cumulative rainfall, average temperature and relative humidity through a mathematical linear model with a determination coefficient (Rsqr of 0.752. Although based on an oversimplified statistical analysis, as far as the vector is concerned, this approach showed to be potentially useful as a starting point to guide control measures for AVL in Montes Claros.

Discovery of markers of exposure specific to bites of Lutzomyia longipalpis, the vector of Leishmania infantum chagasi in Latin America.

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Clarissa Teixeira

2010-03-01

Full Text Available Sand flies deliver Leishmania parasites to a host alongside salivary molecules that affect infection outcomes. Though some proteins are immunogenic and have potential as markers of vector exposure, their identity and vector specificity remain elusive.We screened human, dog, and fox sera from endemic areas of visceral leishmaniasis to identify potential markers of specific exposure to saliva of Lutzomyia longipalpis. Human and dog sera were further tested against additional sand fly species. Recombinant proteins of nine transcripts encoding secreted salivary molecules of Lu. longipalpis were produced, purified, and tested for antigenicity and specificity. Use of recombinant proteins corresponding to immunogenic molecules in Lu. longipalpis saliva identified LJM17 and LJM11 as potential markers of exposure. LJM17 was recognized by human, dog, and fox sera; LJM11 by humans and dogs. Notably, LJM17 and LJM11 were specifically recognized by humans exposed to Lu. longipalpis but not by individuals exposed to Lu. intermedia.Salivary recombinant proteins are of value as markers of vector exposure. In humans, LJM17 and LJM11 emerged as potential markers of specific exposure to Lu. longipalpis, the vector of Leishmania infantum chagasi in Latin America. In dogs, LJM17, LJM11, LJL13, LJL23, and LJL143 emerged as potential markers of sand fly exposure. Testing these recombinant proteins in large scale studies will validate their usefulness as specific markers of Lu. longipalpis exposure in humans and of sand fly exposure in dogs.

Discovery of markers of exposure specific to bites of Lutzomyia longipalpis, the vector of Leishmania infantum chagasi in Latin America.

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Teixeira, Clarissa; Gomes, Regis; Collin, Nicolas; Reynoso, David; Jochim, Ryan; Oliveira, Fabiano; Seitz, Amy; Elnaiem, Dia-Eldin; Caldas, Arlene; de Souza, Ana Paula; Brodskyn, Cláudia I; de Oliveira, Camila Indiani; Mendonca, Ivete; Costa, Carlos H N; Volf, Petr; Barral, Aldina; Kamhawi, Shaden; Valenzuela, Jesus G

2010-03-23

Sand flies deliver Leishmania parasites to a host alongside salivary molecules that affect infection outcomes. Though some proteins are immunogenic and have potential as markers of vector exposure, their identity and vector specificity remain elusive. We screened human, dog, and fox sera from endemic areas of visceral leishmaniasis to identify potential markers of specific exposure to saliva of Lutzomyia longipalpis. Human and dog sera were further tested against additional sand fly species. Recombinant proteins of nine transcripts encoding secreted salivary molecules of Lu. longipalpis were produced, purified, and tested for antigenicity and specificity. Use of recombinant proteins corresponding to immunogenic molecules in Lu. longipalpis saliva identified LJM17 and LJM11 as potential markers of exposure. LJM17 was recognized by human, dog, and fox sera; LJM11 by humans and dogs. Notably, LJM17 and LJM11 were specifically recognized by humans exposed to Lu. longipalpis but not by individuals exposed to Lu. intermedia. Salivary recombinant proteins are of value as markers of vector exposure. In humans, LJM17 and LJM11 emerged as potential markers of specific exposure to Lu. longipalpis, the vector of Leishmania infantum chagasi in Latin America. In dogs, LJM17, LJM11, LJL13, LJL23, and LJL143 emerged as potential markers of sand fly exposure. Testing these recombinant proteins in large scale studies will validate their usefulness as specific markers of Lu. longipalpis exposure in humans and of sand fly exposure in dogs.

Field Evaluation of a New Strategy to Control Lutzomyia longipalpis, Based on Simultaneous Application of an Adulticide-Larvicide Mixture.

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Juan, Laura W; Lucia, Alejandro; Alzogaray, Raúl A; Steinhorst, Ingrid I; López, Karen; Pettersen, Matías; Busse, José; Zerba, Eduardo N

2016-09-01

Leishmania infantum (syn. chagasi) is the etiologic agent of visceral leishmaniasis in Argentina, and the phlebotomine fly Lutzomyia longipalpis is its main vector. The objective of this study was to evaluate the effectiveness of Dragon Max ® , an emulsifiable concentrate formulation containing the pyrethroid permethrin and the larvicide pyriproxyfen, for Lu. longipalpis control under field conditions. The work was conducted in the city of Posadas (Misiones province, Argentina). Comparisons were performed between treated and untreated peridomiciles with poultry, which met previously determined criteria for favoring the presence of Lu. longipalpis. Henhouses and their surrounding area were treated, with the formulation (100 mg of permethrin and 2 mg/m 2 of pyriproxyfen) applied using a hand pump sprayer. Untreated henhouses were used as controls. Phlebotomine abundance was monitored before treatment and then weekly, using Centers for Disease Control and Prevention light traps. Lutzomyia longipalpis was the only phlebotomine species captured. A male/female ratio of 2.5 was observed. The more chickens there were in the henhouses, the greater the number of phlebotomines captured. The treatment resulted in a significant decrease in the number of individuals, which persisted for at least 2 wk. This encouraging result provides a baseline for further studies evaluating the possibility of using Dragon Max as a tool for Lu. longipalpis control.

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

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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

Analysis of sandflies (Diptera: Psychodidae) in Barra do Garças, State of Mato Grosso, Brazil, and the influence of environmental variables on the vector density of Lutzomyia longipalpis (Lutz & Neiva, 1912).

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Queiroz, Mirian Francisca Martins; Varjão, Jane Ramos; Moraes, Sinara Cristina de; Salcedo, Gladys Elena

2012-06-01

Leishmaniasis is an infectious and parasitic zoonotic, non-contagious, vector-borne disease caused by protozoa of the genus Leishmania. In Brazil, the major vector of Leishmania (Leishmania) infantum chagasi (Cunha & Chagas, 1934) is Lutzomyia longipalpis. Barra do Garças, State of Mato Grosso, was designated as a priority area by the Brazilian Ministry of Health for american visceral leishmaniasis, and it is important to identify the vector species present in this municipality. Our objective was to raise sandflies and study the influence of environmental variables on the vector density of Lutzomyia longipalpis. We performed entomological monitoring in 3 districts using Centers for Disease Control and Prevention (CDC) light traps and recorded human cases of american visceral leishmaniasis in the city. We calculated the relative frequency and richness of sandflies and applied a transfer function model to the vector density correlate with relative humidity. The sandfly population was composed of 2 genera and 27 species, totaling 8,097 individuals. Monitoring identified Lutzomyia longipalpis (44%), followed by Lutzomyia lenti (18.9%), Lutzomyia whitmani (13.9%), Lutzomyia carmelinoi (9.1%), Lutzomyia evandroi (5.1%), Lutzomyia termitophila (3.3%), Lutzomyia sordellii (1.9%), and 20 other species (Lutzomyia longipalpis showed occurrence peaks during the rainy season; there was a temporal correlation with humidity, but not with frequency or temperature. The presence of Lutzomyia longipalpis in the urban area of Barra do Garças underscores the changing disease profile, which was previously restricted to the wild environment.

Multilocus analysis of divergence and introgression in sympatric and allopatric sibling species of the Lutzomyia longipalpis complex in Brazil.

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Araki, Alejandra S; Ferreira, Gabriel E M; Mazzoni, Camila J; Souza, Nataly A; Machado, Ricardo C; Bruno, Rafaela V; Peixoto, Alexandre A

2013-01-01

Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Latin America, is a complex of sibling species. In Brazil, a number of very closely related sibling species have been revealed by the analyses of copulation songs, sex pheromones and molecular markers. However, the level of divergence and gene flow between the sibling species remains unclear. Brazilian populations of this vector can be divided in two main groups: one producing Burst-type songs and the Cembrene-1 pheromone and a second more diverse group producing various Pulse song subtypes and different pheromones. We analyzed 21 nuclear loci in two pairs of Brazilian populations: two sympatric populations from the Sobral locality (1S and 2S) in northeastern Brazil and two allopatric populations from the Lapinha and Pancas localities in southeastern Brazil. Pancas and Sobral 2S are populations of the Burst/Cembrene-1 species while Lapinha and Sobral 1S are two putative incipient species producing the same pheromone and similar Pulse song subtypes. The multilocus analysis strongly suggests the occurrence of gene flow during the divergence between the sibling species, with different levels of introgression between loci. Moreover, this differential introgression is asymmetrical, with estimated gene flow being higher in the direction of the Burst/Cembrene-1 species. The results indicate that introgressive hybridization has been a crucial phenomenon in shaping the genome of the L. longipalpis complex. This has possible epidemiological implications and is particularly interesting considering the potential for increased introgression caused by man-made environmental changes and the current trend of leishmaniasis urbanization in Brazil.

[Lutzomyia longipalpis (Diptera: Psychodidae) at a suburban focus of visceral leishmaniasis in the Chicamocha Canyon, Santander, Colombia].

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Flórez, Mónica; Martínez, Junny Patricia; Gutiérrez, Reinaldo; Luna, Katherine Paola; Serrano, Victor Hugo; Ferro, Cristina; Angulo, Víctor Manuel; Sandoval, Claudia Magaly

2006-10-01

Between 1998 and 2000, the occurrence of 8 cases of American visceral leishmaniasis in children from a recently established human settlement in Guatiguará, in the municipality of Piedecuesta (Santander, Colombia) indicated the possible presence of Leishmania transmission in this locality. This observation motivated the current entomological investigation. To determine the relative frequency of Lutzomyia longipalpis inside houses and outdoors, and the natural infection of this vector with Leishmania spp. CDC light traps were used for sampling inside houses and outdoors, and sand flies were collected on human volunteers and domestic animals, and in resting places, during the period from May 1999 through September 2000. Natural infection was determined by PCR, in pools of female Lutzomyia longipalpis. A total of 7,391 phlebotomine sand flies were collected. The predominant species was Lutzomyia longipalpis (Lutz & Neiva), representing 99.5% of captures. In the sand flies collected with CDC light traps, L. longipalpis was more frequently collected indoors than outdoors (p = 0.0001). The total rate of natural infection was 1.93% and a positive correlation was observed between months with higher abundance and the number of infected females entering human dwellings. The results indicate that in Guatiguará Lutzomyia longipalpis, shows marked tendency for the indoors, which has important implications for leishmaniasis transmission. Furthermore, transmission risk is increased during the months of higher abundance due to the entry of a higher number of infected females. From the standpoint of control, this behaviour permits the design of strategies to reduce indoor transmission.

Distribución de Lutzomyia longipalpis en la Mesopotamia Argentina, 2010

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Oscar D. Salomón

2011-02-01

Full Text Available El primer caso autóctono de leishmaniasis visceral (LV en la Argentina se notificó en el año 2006 en Posadas, Misiones, y en el verano 2008-2009 se comprobó la dispersión del vector de LV, Lutzomyia longipalpis y casos de LV canina en la provincia de Corrientes. Para conocer la distribución del riesgo, entre febrero y marzo del 2010 se realizó la búsqueda sistemática del vector de LV en 18 localidades de las provincias de Entre Ríos, Corrientes y en la ciudad de Puerto Iguazú, Misiones, totalizando 313 trampas/noche. Se comprobó la presencia de Lu. longipalpis, por primera vez, en las localidades de Chajarí (Entre Ríos, Alvear, La Cruz, Curuzú Cuatiá y Bella Vista (Corrientes, y en Puerto Iguazú (Misiones. En Santo Tomé y Monte Caseros (Corrientes se volvió a registrar la presencia del vector, y se obtuvieron las trampas con más ejemplares, 830 y 126 Lu. longipalpis trampa/sitio/noche respectivamente. Los resultados muestran que el vector de la LV urbana, continúa dispersándose en el territorio argentino. Simultáneamente, la propagación del parásito, y los consecuentes casos de LV humana se asocian al aumento de reservorios, perros infectados con o sin clínica, debidos al tránsito humano.

Immunization with LJM11 salivary protein protects against infection with Leishmania braziliensis in the presence of Lutzomyia longipalpis saliva.

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Cunha, Jurema M; Abbehusen, Melissa; Suarez, Martha; Valenzuela, Jesus; Teixeira, Clarissa R; Brodskyn, Cláudia I

2018-01-01

Leishmania is transmitted in the presence of sand fly saliva. Protective immunity generated by saliva has encouraged identification of a vector salivary-based vaccine. Previous studies have shown that immunization with LJM11, a salivary protein from Lutzomyia longipalpis, is able to induce a Th1 immune response and protect mice against bites of Leishmania major-infected Lutzomyia longipalpis. Here, we further investigate if immunization with LJM11 recombinant protein is able to confer cross-protection against infection with Leishmania braziliensis associated with salivary gland sonicate (SGS) from Lutzomyia intermedia or Lu. longipalpis. Mice immunized with LJM11 protein exhibited an increased production of anti-LJM11 IgG, IgG1 and IgG2a and a DTH response characterized by an inflammatory infiltrate with the presence of CD4 + IFN-γ + T cells. LJM11-immunized mice were intradermally infected in the ear with L. braziliensis in the presence of Lu. longipalpis or Lu. intermedia SGS. A significant reduction of parasite numbers in the ear and lymph node in the group challenged with L. braziliensis plus Lu. longipalpis SGS was observed, but not when the challenge was performed with L. braziliensis plus Lu. intermedia SGS. A higher specific production of IFN-γ and absence of IL-10 by lymph node cells were only observed in LJM11 immunized mice after infection. After two weeks, a similar frequency of CD4 + IFN-γ + T cells was detected in LJM11 and BSA groups challenged with L. braziliensis plus Lu. longipalpis SGS, suggesting that early events possibly triggered by immunization are essential for protection against Leishmania infection. Our findings support the specificity of saliva-mediated immune responses and reinforce the importance of identifying cross-protective salivary antigens. Copyright © 2017 Elsevier B.V. All rights reserved.

Synthetic sex pheromone attracts the leishmaniasis vector Lutzomyia longipalpis to experimental chicken sheds treated with insecticide

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Brazil Reginaldo P

2010-03-01

Full Text Available Abstract Background Current strategies for controlling American visceral leishmaniasis (AVL have been unable to prevent the spread of the disease across Brazil. With no effective vaccine and culling of infected dogs an unpopular and unsuccessful alternative, new tools are urgently needed to manage populations of the sand fly vector, Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae. Here, we test two potential strategies for improving L. longipalpis control using the synthetic sand fly pheromone (±-9-methylgermacrene-B: the first in conjunction with spraying of animal houses with insecticide, the second using coloured sticky traps. Results Addition of synthetic pheromone resulted in greater numbers of male and female sand flies being caught and killed at experimental chicken sheds sprayed with insecticide, compared to pheromone-less controls. Furthermore, a ten-fold increase in the amount of sex pheromone released from test sheds increased the number of females attracted and subsequently killed. Treating sheds with insecticide alone resulted in a significant decrease in numbers of males attracted to sheds (compared to pre-spraying levels, and a near significant decrease in numbers of females. However, this effect was reversed through addition of synthetic pheromone at the time of insecticide spraying, leading to an increase in number of flies attracted post-treatment. In field trials of commercially available different coloured sticky traps, yellow traps caught more males than blue traps when placed in chicken sheds. In addition, yellow traps fitted with 10 pheromone lures caught significantly more males than pheromone-less controls. However, while female sand flies showed a preference for both blue and yellow pheromone traps sticky traps over white traps in the laboratory, neither colour caught significant numbers of females in chicken sheds, either with or without pheromone. Conclusions We conclude that synthetic pheromone could

Multilocus Analysis of Divergence and Introgression in Sympatric and Allopatric Sibling Species of the Lutzomyia longipalpis Complex in Brazil

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Mazzoni, Camila J.; Souza, Nataly A.; Machado, Ricardo C.; Bruno, Rafaela V.

2013-01-01

Background Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Latin America, is a complex of sibling species. In Brazil, a number of very closely related sibling species have been revealed by the analyses of copulation songs, sex pheromones and molecular markers. However, the level of divergence and gene flow between the sibling species remains unclear. Brazilian populations of this vector can be divided in two main groups: one producing Burst-type songs and the Cembrene-1 pheromone and a second more diverse group producing various Pulse song subtypes and different pheromones. Methodology/Principal Findings We analyzed 21 nuclear loci in two pairs of Brazilian populations: two sympatric populations from the Sobral locality (1S and 2S) in northeastern Brazil and two allopatric populations from the Lapinha and Pancas localities in southeastern Brazil. Pancas and Sobral 2S are populations of the Burst/Cembrene-1 species while Lapinha and Sobral 1S are two putative incipient species producing the same pheromone and similar Pulse song subtypes. The multilocus analysis strongly suggests the occurrence of gene flow during the divergence between the sibling species, with different levels of introgression between loci. Moreover, this differential introgression is asymmetrical, with estimated gene flow being higher in the direction of the Burst/Cembrene-1 species. Conclusions/Significance The results indicate that introgressive hybridization has been a crucial phenomenon in shaping the genome of the L. longipalpis complex. This has possible epidemiological implications and is particularly interesting considering the potential for increased introgression caused by man-made environmental changes and the current trend of leishmaniasis urbanization in Brazil. PMID:24147172

Transmissibility of Leishmania infantum from maned wolves (Chrysocyon brachyurus) and bush dogs (Speothos venaticus) to Lutzomyia longipalpis.

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Mol, Juliana P S; Soave, Semíramis A; Turchetti, Andréia P; Pinheiro, Guilherme R G; Pessanha, Angela T; Malta, Marcelo C C; Tinoco, Herlandes P; Figueiredo, Luiza A; Gontijo, Nelder F; Paixão, Tatiane A; Fujiwara, Ricardo T; Santos, Renato L

2015-09-15

Leishmania (Leishmania) infantum is the cause of visceral leishmaniasis in the Americas. The disease is transmitted mostly through the bite of the invertebrate vector, the phlebotomine Lutzomyia longipalpis in the New World. Although the domestic dog is considered the most important reservoir of the disease, other mammalian, including wildlife, are susceptible to infection. The goal of this study was to perform xenodiagnosis to evaluate the capacity of naturally infected maned wolves (Chrysocyon brachyurus) and bush dogs (Speothos venaticus) to transmit Leishmania infantum to female sand flies (L. longipalpis). Xenodiagnoses were performed in February and August, 2013, when 77.7% (three maned wolves and four bush dogs) or 100% of the animals were positive, respectively. However, parasite loads in the engorged sand flies was low (longipalpis, although the parasite loads in engorged phlebotomines exposed to these animals were very low. Copyright © 2015 Elsevier B.V. All rights reserved.

Novos encontros de flebotomíneos no Estado de São Paulo, Brasil, com especial referência à Lutzomyia longipalpis New finding of Phlebotominae in the State of S. Paulo, Brazil, with special reference to Lutzomyia longipalpis

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Oswaldo Paulo Forattini

1976-03-01

Full Text Available Relata-se o encontro de várias espécies de Phleboteminae, no Estado de São Paulo, Brasil, até agora raramente ou mesmo não assinaladas nessa região. São registrados novos achados de Lutzomyia longipalpis e fornecidos alguns dados sobre as circunstâncias desses encontros.New records on Phlebotominae in the State of S. Paulo, Brazil, are reported. Special attention is dedicated to Lutzomyia longipalpis. Several behavioural aspects of these observations were recorded.

Fine Structure of the Male Reproductive System and Reproductive Behavior of Lutzomyia longipalpis Sandflies (Diptera: Psychodidae: Phlebotominae)

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Peixoto, Alexandre A.; Vigoder, Felipe M.; Bruno, Rafaela V.; Soares, Maurilio J.

2013-01-01

Background The male reproductive system of insects can have several tissues responsible for the secretion of seminal fluid proteins (SFPs), such as testes, accessory glands, seminal vesicles, ejaculatory duct and ejaculatory bulb. The SFPs are transferred during mating and can induce several physiological and behavioral changes in females, such as increase in oviposition and decrease in sexual receptivity after copulation. The phlebotomine Lutzomyia longipalpis is the main vector of visceral leishmaniasis. Despite its medical importance, little is known about its reproductive biology. Here we present morphological aspects of the male L. longipalpis reproductive system by light, scanning and transmission electron microscopy, and compare the mating frequency of both virgin and previously mated females. Results The male L. longipalpis reproductive system is comprised by a pair of oval-shaped testes linked to a seminal vesicle by vasa deferentia. It follows an ejaculatory duct with an ejaculatory pump (a large bulb enveloped by muscles and associated to tracheas). The terminal endings of the vasa deferentia are inserted into the seminal vesicle by invaginations of the seminal vesicle wall, which is composed by a single layer of gland cells, with well-developed endoplasmic reticulum profiles and secretion granules. Our data suggest that the seminal vesicle acts both as a spermatozoa reservoir and as an accessory gland. Mating experiments support this hypothesis, revealing a decrease in mating frequency after copulation that indicates the effect of putative SFPs. Conclusion Ultrastructural features of the L. longipalpis male seminal vesicle indicated its possible role as an accessory gland. Behavioral observations revealed a reduction in mating frequency of copulated females. Together with transcriptome analyses from male sandfly reproductive organs identifying ESTs encoding orthologs of SFPs, these data indicate the presence of putative L. longipalpis SFPs reducing

Fine structure of the male reproductive system and reproductive behavior of Lutzomyia longipalpis sandflies (Diptera: Psychodidae: Phlebotominae).

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Spiegel, Carolina N; Bretas, Jorge A C; Peixoto, Alexandre A; Vigoder, Felipe M; Bruno, Rafaela V; Soares, Maurilio J

2013-01-01

The male reproductive system of insects can have several tissues responsible for the secretion of seminal fluid proteins (SFPs), such as testes, accessory glands, seminal vesicles, ejaculatory duct and ejaculatory bulb. The SFPs are transferred during mating and can induce several physiological and behavioral changes in females, such as increase in oviposition and decrease in sexual receptivity after copulation. The phlebotomine Lutzomyia longipalpis is the main vector of visceral leishmaniasis. Despite its medical importance, little is known about its reproductive biology. Here we present morphological aspects of the male L. longipalpis reproductive system by light, scanning and transmission electron microscopy, and compare the mating frequency of both virgin and previously mated females. The male L. longipalpis reproductive system is comprised by a pair of oval-shaped testes linked to a seminal vesicle by vasa deferentia. It follows an ejaculatory duct with an ejaculatory pump (a large bulb enveloped by muscles and associated to tracheas). The terminal endings of the vasa deferentia are inserted into the seminal vesicle by invaginations of the seminal vesicle wall, which is composed by a single layer of gland cells, with well-developed endoplasmic reticulum profiles and secretion granules. Our data suggest that the seminal vesicle acts both as a spermatozoa reservoir and as an accessory gland. Mating experiments support this hypothesis, revealing a decrease in mating frequency after copulation that indicates the effect of putative SFPs. Ultrastructural features of the L. longipalpis male seminal vesicle indicated its possible role as an accessory gland. Behavioral observations revealed a reduction in mating frequency of copulated females. Together with transcriptome analyses from male sandfly reproductive organs identifying ESTs encoding orthologs of SFPs, these data indicate the presence of putative L. longipalpis SFPs reducing sexual mating frequency of

Association between Leishmania infantum DNA in the hair of dogs and their infectiousness to Lutzomyia longipalpis.

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de Sousa Gonçalves, Rafaela; Franke, Carlos R; Magalhães-Junior, Jairo T; Souza, Bárbara M P S; Solcà, Manuela S; Larangeira, Daniela F; Barrouin-Melo, Stella Maria

2016-12-15

Diagnosis of infection with Leishmania infantum by DNA detection in the hair has been recently demonstrated in dogs and wild animals. Our objective was to investigate if polymerase chain reaction (PCR) in hair might be used to identify infectious dogs. Thus, we assessed the infectiousness to Lutzomyia longipalpis by xenodiagnosis in comparison with the detection of L. infantum DNA by PCR in the hair, and with serology for anti-Leishmania IgG by ELISA in 15 positive dogs for L. infantum infection. Eight healthy dogs were included as negative controls. Among the 15 infected dogs, 13 were found positive in the ELISA (87%), 12 were PCR positive in the hair (80%), and 10 were positive in xenodiagnosis (67%). Positivity in the hair was associated with positivity in spleen (p=0.0003), seropositivity for antibodies (p=0.0006) and parasite transmission to L. longipalpis (p=0.0028). Considering the benefits to animal welfare and feasibility of hair sampling method, studies in larger and more diverse populations of naturally infected dogs from endemic areas should be conducted to evaluate the sensitivity, specificity, and predictive values of PCR using hair as a possible biomarker of infectiousness in dogs. Copyright © 2016 Elsevier B.V. All rights reserved.

Occurrence of Lutzomyia longipalpis (Phlebotominae) and canine visceral leishmaniasis in a rural area of Ilha Solteira, SP, Brazil.

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Spada, Julio Cesar Pereira; Silva, Diogo Tiago da; Martins, Kennya Rozy Real; Rodas, Lílian Aparecida Colebrusco; Alves, Maria Luana; Faria, Glaucia Amorim; Buzutti, Marcelo Costa; Silva, Hélio Ricardo; Starke-Buzetti, Wilma Aparecida

2014-01-01

This study aimed to investigate the occurrence of Lutzomyia longipalpis and also the canine visceral leishmaniasis (CVL) in a rural area of Ilha Solteira, state of São Paulo. Blood samples were collected from 32 dogs from different rural properties (small farms) and were analyzed by ELISA and the indirect immunofluorescence antibody test (IFAT) in order to diagnose CVL. From these serological tests, 31.25% of the dogs were positive for CVL and these were distributed in 66.7% (8/12) of the rural properties, which were positive for L. longipalpis. CDC (Center for Disease Control and Prevention) light traps were installed in 12 properties (one per property) and insects were caught on three consecutive days per month for one year. L. longipalpis was present on 100% of the rural properties visited, at least once during the twelve-month interval, totaling 64 males and 25 females. The insects were more numerous after the peak of the rain, but the association between prevalence of peridomestic vectors and the climatic data (precipitation, relative air humidity and temperature) and the occurrences of CVL among dogs on each rural property were not statistical significant (p longipalpis indicate that more attention is necessairy for the control of this disease in the rural area studied.

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.

Effect of fruit and leaves of Meliaceae plants (Azadirachta indica and Melia azedarach) on the development of Lutzomyia longipalpis larvae (Diptera: Psychodidae: Phlebotominae) under experimental conditions.

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Andrade-Coelho, Cláudia A; Souza, Nataly A; Gouveia, Cheryl; Silva, Vanderlei C; Gonzalez, Marcelo S; Rangel, Elizabeth F

2009-09-01

This no-choice, laboratory study focuses on the feeding of dried, ground, homogeneous powdered, unprocessed fruit and leaves of Azadirachta indica and Melia azedarach to Lutzomyia longipalpis larvae to determine the effects on their mortality and metamorphosis. A. indica and M. azedarach fruit and leaves significantly increased larval mortality in comparison to larvae fed the untreated, standard diet. A. indica fruit and leaves blocked the molting of the larvae to the fourth instar, resulting in them remaining as third instars until the end of the experiment. M. azedarach fruit also blocked the molting of larvae, which remained permanently in the fourth instar. Feeding M. azedarach leaves resulted in greater molt inhibition. All insects in this group stopped their development as second-instar larvae. No antifeedant effect was detected for any experimental treatment. The results indicate that nontoxic, unprocessed materials obtained from A. indica and M. azedarach are potent development inhibitors of L. longipalpis larvae.

[Expansion of the distribution of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae) in the department of Caldas: Increased risk of visceral leishmaniasis].

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Acosta, Luz Adriana; Mondragón-Shem, Karina; Vergara, Daniela; Vélez-Mira, Andrés; Cadena, Horacio; Carrillo-Bonilla, Lina

2013-01-01

Diverse taxonomical and molecular studies suggest that Lutzomyia longipalpis , main vector of visceral leishmaniasis in Latin America, is a complex of species widely distributed throughout the continent and adapted to different habitats. To carry out entomological surveillance in the area of influence of the Miel I Hydroelectric Plant. Adhesive traps were used in a transect covering an area of approximately 400 km for the capture of insects, which were then identified using the Young and Duncan taxonomical key. This study reports the presence of Lutzomyia longipalpis in the municipalities of Norcasia at an altitude of 392 masl, and in Marquetalia at 1,387 masl. We suggest that the increase in the geographical and altitudinal distribution could be related to the existence of the Lu. longipalpis species complex, or to environmental factors, such as the rise in temperature due to global climate changes, which create the establishment of Lu. longipalpis , generating a new epidemiological risk for new visceral leishmaniasis foci in the country.

Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) in the region of Saquarema: potential area of visceral leishmaniasis transmission in the state of Rio de Janeiro, Brazil.

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Brazil, Reginaldo Peçanha; Pontes, Michelle Cristina de Queiroz; Passos, Wagner Lança; Fuzari, Andressa Alencaste; Brazil, Beatriz Gomes

2012-02-01

Lutzomyia longipalpis is the main vector of Leishmania infantum chagasi in the Americas. Phlebotomine captures were conducted during 2008 and 2009 in a rural area endemic for cutaneous leishmaniasis located in the municipality of Saquarema, Rio de Janeiro. Among other species captured, we observed the presence of Lutzomyia longipalpis. This is the first report of the occurrence of Lutzomyia longipalpis in this region, demonstrating the potential risk of visceral leishmaniasis transmission in the coastal area of the State of Rio de Janeiro. Therefore, active vigilance by all municipalities in the area is necessary.

Age structure, blood-feeding behavior, and Leishmania chagasi infection in Lutzomyia longipalpis (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

1995-09-01

Ecological studies on the sand fly Lutzomyia longipalpis (Lutz & Neiva) were conducted during 1990-1992 in a small rural community in Colombia where American visceral leishmaniasis (AVL) is endemic. Subsamples of sand flies collected weekly from pigpens, the interior of houses, and natural outdoor resting sites were dissected to determine physiological age and Leishmania chagasi Cunha & Chagas infection rates. Eleven female L. longipalpis had flagellates in their gut, 2 of which were successfully cultured and identified as Leishmania chagasi. The reproductive status, stage of ovarian development, and trophic history of female sand flies varied among sites, habitats, and time of collection. The percentage of parous females ranged from about one-third to two-thirds overall and varied seasonally. Of most relevance to AVL transmission was the finding that 8% of L. longipalpis females were multiparous. In addition, our data suggest that L. longipalpis rest inside houses after blood-feeding outdoors, and that this species can blood-feed more than once during a single gonotrophic cycle.

Lutzomyia longipalpis Presence and Abundance Distribution at Different Micro-spatial Scales in an Urban Scenario.

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Santini, María Soledad; Utgés, María Eugenia; Berrozpe, Pablo; Manteca Acosta, Mariana; Casas, Natalia; Heuer, Paola; Salomón, O Daniel

2015-01-01

The principal objective of this study was to assess a modeling approach to Lu. longipalpis distribution in an urban scenario, discriminating micro-scale landscape variables at microhabitat and macrohabitat scales and the presence from the abundance of the vector. For this objective, we studied vectors and domestic reservoirs and evaluated different environmental variables simultaneously, so we constructed a set of 13 models to account for micro-habitats, macro-habitats and mixed-habitats. We captured a total of 853 sandflies, of which 98.35% were Lu. longipalpis. We sampled a total of 197 dogs; 177 of which were associated with households where insects were sampled. Positive rK39 dogs represented 16.75% of the total, of which 47% were asymptomatic. Distance to the border of the city and high to medium density vegetation cover ended to be the explanatory variables, all positive, for the presence of sandflies in the city. All variables in the abundance model ended to be explanatory, trees around the trap, distance to the stream and its quadratic, being the last one the only one with negative coefficient indicating that the maximum abundance was associated with medium values of distance to the stream. The spatial distribution of dogs infected with L. infantum showed a heterogeneous pattern throughout the city; however, we could not confirm an association of the distribution with the variables assessed. In relation to Lu. longipalpis distribution, the strategy to discriminate the micro-spatial scales at which the environmental variables were recorded allowed us to associate presence with macrohabitat variables and abundance with microhabitat and macrohabitat variables. Based on the variables associated with Lu. longipalpis, the model will be validated in other cities and environmental surveillance, and control interventions will be proposed and evaluated in the microscale level and integrated with socio-cultural approaches and programmatic and village (mesoscale

A field study of the survival and dispersal pattern of Lutzomyia longipalpis in an endemic area of visceral leishmaniasis in Brazil

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Casanova, Claudio; Pimentel Bergamaschi, Denise

2018-01-01

Zoonotic Visceral leishmaniasis (ZVL) is a neglected tropical disease that in the Americas is caused by the infection of Leishmania infantum and the domestic dog (Canis familiaris) is the main parasite reservoir in urban areas. The parasite is mainly transmitted by populations of the sibling species Lutzomyia longipalpis that has been spreading in countries including Brazil, Argentina, Paraguay and more recently Uruguay. Although bionomic parameters such as population survival and the duration of the gonotrophic cycle are critical in evaluating vector capacity, field studies have rarely been applied to sand fly populations. The present study sought to evaluate basic bionomic parameters related to the vectorial capacity of the (S)-9-methylgermacrene-B population of the Lu. longipalpis complex in a visceral leishmaniasis area of Sao Paulo state. The daily survival rate, the duration of the gonotrophic cycle and the dispersal pattern were evaluated through the mark- release-recapture method. A total of 1,547 males and 401 females were marked and released in five experiments carried out between February 2013 and February 2014. The higher recapture rates occurred within 100 meters of the release point and the estimated daily survival rates varied between 0.69 and 0.89 for females and between 0.69 and 0.79 for males. The minimum duration of the gonotrophic cycle observed was five days. The absolute population size, calculated ranged from 900 to 4,857 females and from 2,882 to 9,543 males. Our results demonstrate a high survival rate of this vector population and low dispersal that could be associated with the presence of all necessary conditions for its establishment and maintenance in the peridomiciles of this area. Our findings contribute to the basic data necessary for the understanding of ZVL dynamics and the evaluation of the implementation of prevention and control measures. PMID:29608563

Distribución de Lutzomyia longipalpis en el Chaco Argentino, 2010

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Oscar D. Salomón

2011-06-01

Full Text Available El riesgo de leishmaniasis visceral (LV urbana epidémica se registró por primera vez en la Argentina en el año 2004, por presencia del vector Lutzomyia longipalpis en la provincia de Formosa, la provincia de Misiones registra casos de LV humana, LV canina y vector en el año 2006, y la provincia de Corrientes en el verano 2008-2009. En la provincia de Santiago del Estero los casos de LV humana y LV canina en el año 2008 estuvieron asociados posiblemente a vectores secundarios. Por ello, para conocer la distribución del riesgo en la región del Chaco, entre enero y abril del 2010 se realizó la búsqueda sistemática del vector de LV en 30 localidades de las provincias de Formosa, Chaco y en la ciudad de Reconquista, Santa Fe (224 trampas/noche. Se comprobó la presencia de Lu. longipalpis, por primera vez, en las localidades de Resistencia y Puerto Antequera (Chaco. En Clorinda y Puerto Pilcomayo (Formosa se obtuvieron las trampas con más ejemplares, 158 y 241 Lu. longipalpis trampa/sitio/noche respectivamente. Los resultados muestran que el vector de la LV urbana epidémica continúa dispersándose en el territorio argentino, habiendo ingresado a la provincia de Chaco. La notificación de casos esporádicos en la región chaqueña, transmitidos por vectores secundarios, como Lu. migonei, podría aumentar también debido a la vigilancia intensificada, y a la dispersión del parásito asociada al tránsito de perros infectados, sintomáticos o asintomáticos.

Expression, purification, crystallization and crystallographic study of Lutzomyia longipalpis LJL143

International Nuclear Information System (INIS)

Kelleher, Alan; Liu, Zhuyun; Seid, Christopher A.; Zhan, Bin; Asojo, Oluwatoyin A.

2015-01-01

LJL143, a salivary protein from L. longipalpis, was produced using P. pastoris and crystallized in space group P2 1 2 1 2 1 . Leishmaniasis is a neglected vector-borne disease with a global prevalence of over 12 million cases and 59 000 annual deaths. Transmission of the parasite requires salivary proteins, including LJL143 from the New World sandfly Lutzomyia longipalpis. LJL143 is a known marker of sandfly exposure in zoonotic hosts. LJL143 was crystallized from soluble protein expressed using Pichia pastoris. X-ray data were collected to 2.6 Å resolution from orthorhombic crystals belonging to space group P2 1 2 1 2 1 , with average unit-cell parameters a = 57.39, b = 70.24, c = 79.58 Å. The crystals are predicted to have a monomer in the asymmetric unit, with an estimated solvent content of 48.5%. LJL143 has negligible homology to any reported structures, so the phases could not be determined by molecular replacement. All attempts at S-SAD failed and future studies include experimental phase determination using heavy-atom derivatives

Presence of the fire ant Solenopsis invicta (Westwood) (Hymenoptera: Formicidae) stimulates burrowiong behavior by larvae of the sandfly Lutzomyia longipalpis (Lutz & Neiva)(Diptera: Psychodidae)

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Harvey, J.A.; Hamilton, J.G.C.; Ward, R.D.

2010-01-01

The sandfly Lutzomyia longipalpis (Lutz & Neiva) vectors leishmaniasis in the neotropics. Although much is known about the biology of adult flies, little is known about interactions with its natural enemies. Here, we examined behavior of larvae of L4 L.longipalpis on a soil substrate when exposed to

Carbohydrate digestion in Lutzomyia longipalpis' larvae (Diptera - Psychodidae).

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Vale, Vladimir F; Moreira, Bruno H; Moraes, Caroline S; Pereira, Marcos H; Genta, Fernando A; Gontijo, Nelder F

2012-10-01

Lutzomyia longipalpis is the principal species of phlebotomine incriminated as vector of Leishmania infantum, the etiological agent of visceral leishmaniasis in the Americas. Despite its importance as vector, almost nothing related to the larval biology, especially about its digestive system has been published. The objective of the present study was to obtain an overview of carbohydrate digestion by the larvae. Taking in account that phlebotomine larvae live in the soil rich in decaying materials and microorganisms we searched principally for enzymes capable to hydrolyze carbohydrates present in this kind of substrate. The principal carbohydrases encountered in the midgut were partially characterized. One of them is a α-amylase present in the anterior midgut. It is probably involved with the digestion of glycogen, the reserve carbohydrate of fungi. Two other especially active enzymes were present in the posterior midgut, a membrane bound α-glucosidase and a membrane bound trehalase. The first, complete the digestion of glycogen and the other probably acts in the digestion of trehalose, a carbohydrate usually encountered in microorganisms undergoing hydric stress. In a screening done with the use of p-nitrophenyl-derived substrates other less active enzymes were also observed in the midgut. A general view of carbohydrate digestion in L. longipalpis was presented. Our results indicate that soil microorganisms appear to be the main source of nutrients for the larvae. Copyright © 2012 Elsevier Ltd. All rights reserved.

The first record of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae) in the State of Paraná, Brazil.

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Santos, Demilson Rodrigues Dos; Ferreira, Adão Celestino; Bisetto Junior, Alceu

2012-10-01

We report the first find of Lutzomyia longipalpis in the State of Paraná, Brazil. The specimens were captured in the urban area of the municipality of Foz do Iguaçu, with Falcão light traps, in domiciliary and peridomiciliary areas of 61 properties, on two consecutive nights from 18:00 to 06:00hs in March 2012. We captured 40 specimens of Lu. longipalpis and 54 specimens of other sandfly species. This find expands knowledge of the geographical distribution of this sandfly in Brazil.

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.

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.

Expression, purification, crystallization and crystallographic study of Lutzomyia longipalpis LJL143

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Kelleher, Alan; Liu, Zhuyun; Seid, Christopher A.; Zhan, Bin; Asojo, Oluwatoyin A., E-mail: asojo@bcm.edu [Baylor College of Medicine, 1102 Bates Avenue, Suite 550, Mail Stop BCM320, Houston, TX 77030-3411 (United States)

2015-06-27

LJL143, a salivary protein from L. longipalpis, was produced using P. pastoris and crystallized in space group P2{sub 1}2{sub 1}2{sub 1}. Leishmaniasis is a neglected vector-borne disease with a global prevalence of over 12 million cases and 59 000 annual deaths. Transmission of the parasite requires salivary proteins, including LJL143 from the New World sandfly Lutzomyia longipalpis. LJL143 is a known marker of sandfly exposure in zoonotic hosts. LJL143 was crystallized from soluble protein expressed using Pichia pastoris. X-ray data were collected to 2.6 Å resolution from orthorhombic crystals belonging to space group P2{sub 1}2{sub 1}2{sub 1}, with average unit-cell parameters a = 57.39, b = 70.24, c = 79.58 Å. The crystals are predicted to have a monomer in the asymmetric unit, with an estimated solvent content of 48.5%. LJL143 has negligible homology to any reported structures, so the phases could not be determined by molecular replacement. All attempts at S-SAD failed and future studies include experimental phase determination using heavy-atom derivatives.

Effects of azadirachtin on the development and mortality of Lutzomyia longipalpis larvae (Diptera: Psychodidae: Phlebotominae).

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Andrade Coelho, Claudia Alves; de Souza, Nataly Araújo; Feder, Maria Denise; da Silva, Carlos Eugênio; Garcia, Elói de Souza; Azambuja, Patricia; Gonzalez, Marcelo Salabert; Rangel, Elizabeth F

2006-03-01

The effects of azadirachtin A added to the standard diet on the development, mortality, and metamorphosis of Lutzomyia longipalpis Lutz & Neiva, 1912 were studied. Concentrations of 0.1, 1.0, and 10.0 microg of azadirachtin/mg of diet significantly increased larval mortality in comparison with nontreated insects. Concentrations 0.1 and 1.0 microg blocked the molt of larvae, which remained as third instars until the end of the experiment. The 10 microg/mg concentration resulted in greater molt inhibition. In this group, all insects stopped their development as second instars. Simultaneous addition of ecdysone (1 microg/mg) to the standard diet containing azadirachtin counteracted the effects of azadirachtin on mortality and inhibition of ecdysis. These results indicate that azadirachtin is a potent growth inhibitor of L. longipalpis.

Sôbre o encontro de Lutzomyia longipalpis (Lutz & Neiva, 1912 no Estado de São Paulo, Brasil Lutzomyia longipalpis (Lutz & Neiva, 1912 detected in the State of São Paulo, Brazil

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Oswaldo Paulo Forattini

1970-06-01

Full Text Available Relata-se o encontro de Lutzomyia longipalpis na localidade denominada Bairro do Arado, município de Salto de Pirapora, Estado de São Paulo, Brasil. Trata-se do primeiro registro concreto da presença dessa espécie em território paulista. Sugere-se a necessidade de investigar o significado epidemiológico dêsse achado.Lutzomyia longipalpis was found at the rural area named "Bairro do Arado", Salto de Pirapora County, São Paulo State, Brazil. This vector of visceral leihmaniasis is by the first time, surely recorded in the São Paulo State. The specimens were found in a chicken house built on rocks for observing the possibility of Triatoma arthurneivai colonization in artificial ecotopes. This suggests that the sandfly breeding places will possibly be found between or under the stones harbouring that triatomid bug. The necessity of epidemiological studies related to this found is emphasized.

Molecular analysis of an odorant-binding protein gene in two sympatric species of Lutzomyia longipalpis s.l.

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Ana Karina Kerche Dias

2013-01-01

Full Text Available Lutzomyia longipalpis s.l. is the main vector of American visceral leishmaniasis (AVL and occurs as a species complex. DNA samples from two Brazilian sympatric species that differ in pheromone and courtship song production were used to analyse molecular polymorphisms in an odorant-binding protein ( obp29 gene. OBPs are proteins related to olfaction and are involved in activities fundamental to survival, such as foraging, mating and choice of oviposition site. In this study, the marker obp29 was found to be highly polymorphic in Lu. longipalpis s.l. , with no fixed differences observed between the two species. A pairwise fixation index test indicated a moderate level of genetic differentiation between the samples analysed.

PRIMEIRA OCORRÊNCIA DE Lutzomyia (Lutzomyia) longipalpis LUTZ & NEIVA, 1912 (DIPTERA: PSYCHODIDAE: PHLEBOTOMINAE) NO ESTADO DO AMAPÁ, BRASIL.

OpenAIRE

Allan Kardec Ribeiro Galardo; Clicia Denis Galardo; Aderbal Amanajás Santana; José Claudio Cortes Mendes; Francisco Redivaldo Almeida de Souza; Jorge Pereira Duarte; José Ferreira Saraiva; Luiz Carlos Leite Pinna; Raimundo Wilson Carvalho; Ana Paula Sales de Andrade Correa; Ana Cristina da Silva Ferreira Lima

2013-01-01

Relata-se a primeira ocorrência de Lutzomyia longipalpis, o mais importante vetor biológico do agente causador da Leishmaniose Visceral Americana (LVA), no município de Ferreira Gomes, estado do Amapá, Brasil e por tratar-se de uma espécie com grande importância epidemiológica, os autores alertam as autoridades locais.   Palavras-chave: Amapá, Ferreira Gomes, Lutzomyia longipalpis, Leishmaniose Visceral Americana.   DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v3n2p179-...

Clocks do not tick in unison: isolation of Clock and vrille shed new light on the clockwork model of the sand fly Lutzomyia longipalpis.

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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.

Biologia de Lutzomyia intermedia (Lutz & Neiva, 1912 e Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera, Psychodidae em condições experimentais: II. Influência de fatores ambientais no comportamento das formas imaturas e adultas Biology of Lutzomyia intermedia (Lutz & Neiva, 1912 and Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera, Psychodidae in experimental conditions: II. Influence of environmental factors in the behavior of immature stages and adults

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Elizabeth F. Rangel

1987-09-01

Full Text Available Com o objetivo de ampliar os conheciemntos sobre a biologia de Lutzomyia intermedia e Lutzomya longipalpis, mantidos em colônias autônomas no laboratório, apresentamos dados referentes a alterações em seu comportamento determinadas por influência de fatores ambientais. L. longipalpis foi mais fácil de criar, mais produtiva e mais resitente ás variações das condições ambientais; suga a qualquer hora do dia, enquanto que L. intermedia prefere fazê-lo ao crepúsculo e à noite, quando também ocorrem masi freqüentemente as desovas e as ecdises dos adultos das duas espécies. As fases imaturas de ambas as espécies resistem à imersão na água por até 1 hora e a baixa temperatura de 5ºC por até 6 horas.Proceeding on our studies on the biology of Lutzomyia intermedia and Lutzomyia longipalpis in closed colonies in the laboratory, we here present our observations on changes in their behavior caused by environmental conditions. L. longipaldis was easier to breed, more productive and more resistant to environmental changes; it feeds at any time of the day or night, while L. intermedia prefers to do it at sunset and at night, the preferencial time for oviposition and ecdysis of adults of both species. The immature stages of both species resisted to immersion in water for up to 1 hour and low temperature (5ºC for 1 to 6 hours.

Cloning and characterization of a V-ATPase subunit C from the American visceral leishmaniasis vector Lutzomyia longipalpis modulated during development and blood ingestion

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JM Ramalho-Ortigão

2007-06-01

Full Text Available Visceral leishmaniasis (VL is a serious tropical disease that affects approximately 500 thousand people worldwide every year. In the Americas, VL is caused by the parasite Leishmania (Leishmania infantum chagasi mainly transmitted by the bite of the sand fly vector Lutzomyia longipalpis. Despite recent advances in the study of interaction between Leishmania and sand flies, very little is known about sand fly protein expression profiles. Understanding how the expression of proteins may be affected by blood feeding and/or presence of parasite in the vector's midgut might allow us to devise new strategies for controlling the spread of leishmaniasis. In this work, we report the characterization of a vacuolar ATPase subunit C from L. longipalpis by screening of a midgut cDNA library with a 220 bp fragment identified by means of differential display reverse transcriptase-polymerase chain reaction analysis. The expression of the gene varies along insect development and is upregulated in males and bloodfed L. longipalpis, compared to unfed flies.

The first report of the main vector of visceral leishmaniasis in America, Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae: Phlebotominae), in the state of Rio Grande do Sul, Brazil.

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Souza, Getúlio Dornelles; Santos, Edmilson dos; Andrade Filho, José Dilermando

2009-12-01

Visceral leishmaniasis (VL) is a widespread zoonosis in Brazil and, up to now, there has been no record of the main vector of its agent, Lutzomyia longipalpis, in the Southern Region. Due to the diagnosis of VL in a dog in October 2008 in the city of São Borja, in the southernmost Brazilian state of Rio Grande do Sul, a collection of phlebotomines was undertaken to detect the presence of the vector Lu. longipalpis. The captures were carried out with CDC light traps on three consecutive nights in 2008. A total of 39 specimens of Lu. longipalpis were captured, thereby increasing the knowledge of the geographical distribution of this important vector.

Lutzomyia longipalpis (Diptera: Psychodidae en un foco suburbano de leishmaniosis visceral en el Cañón del Chicamocha en Santander, Colombia.

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Mónica Flórez

2006-10-01

Full Text Available Introducción. Entre los años 1998-2000 la aparición de 8 casos de leishmaniosis visceral americana en niños de un asentamiento humano de reciente establecimiento en la localidad de Guatiguará del municipio de Piedecuesta (Santander Colombia, señaló la posible presencia de un ciclo de transmisión de Leishmania en dicho lugar que motivó el presente estudio entomológico. Objetivos. Determinar frecuencia relativa en el intra y peridomicilio de Lutzomyia longipalpis y la infección natural de este vector con Leishmania spp. Materiales y métodos. Se utilizaron para el muestreo trampas CDC intra y peridomiciliares, capturas sobre cebo humano, cebo animal y en sitios de reposo, en el periodo de mayo de 1999 a septiembre del 2000. La infección natural se determinó mediante la técnica de PCR, en pooles de hembras de Lutzomyia longipalpis. Resultados. Se capturaron 7.391 flebótomos. La especie predominante fue Lutzomyia longipalpis (Lutz & Neiva, con un 99,5% de las capturas. En las recolecciones con trampas de luz CDC, L. longipalpis tuvo una mayor frecuencia en el intradomicilio que en el peridomicilio (p=0,0001. La tasa total de infección natural fue del 1,93% y se observó una correlación positiva entre los meses de mayor abundancia y el número de hembras infectadas que ingresan al domicilio. Conclusiones. Los resultados indican que en la localidad de Guatiguará Lutzomyia longipalpis, presenta tendencias marcadas hacia el intradomicilio, lo cual tiene serias implicaciones en la transmisión por cuanto el riesgo de transmisión se ve aumentado durante los meses de mayor abundancia por el ingreso de un mayor número de hembras infectadas. Desde el punto de vista de control este comportamiento permite diseñar estrategias que disminuyan la transmisión del parásito en el interior del domicilio.

Presença de Lutzomyia longipalpis em foco de leishmaniose visceral americana onde o vetor provável é somente o Lutzomyia cruzi. Corumbá, Mato Grosso do Sul

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Santos, Soraya Oliveira dos; Arias, Jorge R.; Hoffmann, Marta de Paiva; Furlan, Mara Beatriz Grotta; Ferreira, Wilson Francisco; Pereira, Claucio; Ferreira, Lourival

2003-01-01

The present communication reports the presence of Lutzomyia longipalpis in Corumbá, Mato Grosso do Sul, where the principal vector is Lutzomyia cruzi.A presente comunicação relata a presença do Lutzomyia longipalpis em Corumbá, Mato Grosso do Sul, onde o vetor principal é o Lutzomyia cruzi.

Expression pattern of glycoside hydrolase genes in Lutzomyia longipalpis reveals key enzymes involved in larval digestion

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Caroline da Silva Moraes

2014-08-01

Full Text Available The sand fly Lutzomyia longipalpis is the most important vector of American Visceral Leishmaniasis. Adults are phytophagous (males and females or blood feeders (females only, and larvae feed on solid detritus. Digestion in sand fly larvae has scarcely been studied, but some glycosidase activities putatively involved in microorganism digestion were already described. Nevertheless, the molecular nature of these enzymes, as the corresponding genes and transcripts, were not explored yet. Catabolism of microbial carbohydrates in insects generally involves β-1,3-glucanases, chitinases and digestive lysozymes. In this work, the transcripts of digestive β-1,3-glucanase and chitinases were identified in the L. longipalpis larvae throughout analysis of sequences and expression patterns of glycoside hydrolases families 16, 18 and 22. The activity of one i-type lysozyme was also registered. Interestingly, this lysozyme seems to play a role in immunity, rather than digestion. This is the first attempt to identify the molecular nature of sand fly larval digestive enzymes.

Expression pattern of glycoside hydrolase genes in Lutzomyia longipalpis reveals key enzymes involved in larval digestion

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Moraes, Caroline da Silva; Diaz-Albiter, Hector M.; Faria, Maiara do Valle; Sant'Anna, Maurício R. V.; Dillon, Rod J.; Genta, Fernando A.

2014-01-01

The sand fly Lutzomyia longipalpis is the most important vector of American Visceral Leishmaniasis. Adults are phytophagous (males and females) or blood feeders (females only), and larvae feed on solid detritus. Digestion in sand fly larvae has scarcely been studied, but some glycosidase activities putatively involved in microorganism digestion were already described. Nevertheless, the molecular nature of these enzymes, as the corresponding genes and transcripts, were not explored yet. Catabolism of microbial carbohydrates in insects generally involves β-1,3-glucanases, chitinases, and digestive lysozymes. In this work, the transcripts of digestive β-1,3-glucanase and chitinases were identified in the L. longipalpis larvae throughout analysis of sequences and expression patterns of glycoside hydrolases families 16, 18, and 22. The activity of one i-type lysozyme was also registered. Interestingly, this lysozyme seems to play a role in immunity, rather than digestion. This is the first attempt to identify the molecular nature of sand fly larval digestive enzymes. PMID:25140153

[In vitro insecticidal activity of seed neem oil on Lutzomyia longipalpis (Diptera: Psychodidae)].

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Maciel, Michelline V; Morais, Selene M; Bevilaqua, Claudia M L; Silva, Rafaella A; Barros, Renata S; Sousa, Raimundo N; Sousa, Lindemberg C; Machado, Lyeghyna K A; Brito, Edy S; Souza-Neto, Manoel A

2010-01-01

Lutzomyia longipalpis is the main vector of visceral leishmaniasis in Brazil. The objective was to evaluate the effect of oil from (Azadirachta indica) neem seeds on eggs, larvae and adults of the vector. The insects were captured in the field and kept in the laboratory at +/- 27 °C and 80% relative humidity. Five treatments with different concentrations were performed using two negative controls (distilled water and Tween 80) and a positive control. The eggs were sprayed with the oil at different concentrations and the number of hatched larvae evaluated for 10 days. Mortality of larvae was observed to pupation and adult mortality was observed after 24, 48, and 72 hours. Statistical analysis was performed by Tukey test at 5% probability. The highest oil concentration of eggs obtained 65.16 +/- 3.24% efficacy for reducing egg hatching. The test with larvae showed 67.75 +/- 2.21% efficacy at a concentration of 100 mg.mL⁻¹. In adults, the efficacy of the 100 mg.mL⁻¹ concentration was 96.64 +/- 4.11% after 24 hours. The phytochemical analysis revealed the presence of triterpenes. These results demonstrate the potential use of this oil in the control of this vector.

Natural hybrid of Leishmania infantum/L. donovani: development in Phlebotomus tobbi, P. perniciosus and Lutzomyia longipalpis and comparison with non-hybrid strains differing in tissue tropism.

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Seblova, Veronika; Myskova, Jitka; Hlavacova, Jana; Votypka, Jan; Antoniou, Maria; Volf, Petr

2015-11-25

Infection caused by parasites from L. donovani complex can manifest as a serious visceral disease or a self-healing milder cutaneous form. The different tropism and pathology in humans is caused by the interaction between parasites, host and vector determinants but the mechanisms are not well understood. In Cukurova region in Turkey we previously identified a major focus of cutaneous leishmaniasis caused by L. donovani/infantum hybrids (CUK strain) and isolated this parasite from the locally abundant sand fly, Phlebotomus tobbi. Here, we present the first experimental study with P. tobbi. We tested the susceptibility of this species to various Leishmania under laboratory conditions, characterized glycoproteins in the P. tobbi midgut putatively involved in parasite-vector interaction and compared the development of the CUK strain in the sand fly with one other dermotropic and three viscerotropic strains belonging to the L. donovani complex. Females of laboratory reared P. tobbi, P. perniciosus and Lutzomyia longipalpis were infected using membrane feeding on rabbit blood containing promastigotes of various Leishmania species with different tropisms. The individual guts were checked microscopically for presence and localization of Leishmania parasites; the number of parasites was assessed more precisely by qPCR. In addition, glycosylation of midgut proteins of P. tobbi was studied by lectin blotting of midgut lysate with lectins specific for terminal sugars of N-type and O-type glycans. High infection rates, heavy parasite loads and late-stage infection with colonization of the stomodeal valve were observed in P. tobbi infected by Leishmania major or L. infantum CUK hybrid. In parallel, lectin blotting revealed the presence of O-glycosylated proteins in the P. tobbi midgut. In P. perniciosus and L. longipalpis all five Leishmania strains tested developed well. In both vectors, significantly higher parasite numbers were detected by qPCR for dermotropic L. donovani

Observations on the feeding habits of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae) in Campo Grande, an endemic area of visceral leishmaniasis in Mato Grosso do Sul, Brazil.

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de Oliveira, Alessandra Gutierrez; Marassá, Ana Maria; Consales, Cleide Aschenbrenner; Dorval, Maria Elizabeth Cavalheiros; Fernandes, Carlos Eurico; de Oliveira, Gilliard Rezende; Brazil, Reginaldo Peçanha; Galati, Eunice Aparecida Bianchi

2008-09-01

Sand flies were captured weekly with CDC light traps from December 2003 to November 2005 in three areas of Campo Grande, in the Brazilian state of Mato Grosso do Sul. These areas incorporated two patches of remnant forest and five houses. The blood meals of engorged female sand flies were identified using the avidin-biotin system of immunoenzymatic ELISA capture. Most (327/355) of the females analysed were Lutzomyia longipalpis, of which 66.4% reacted with human blood, 64.8% with that of birds and 8.9% with that of dogs. Females that had taken human blood predominated in the residential areas and two forest patches. The following combinations of blood were also detected for L. longipalpis in some of the samples analysed: bird+human (43.4%), bird+human+dog (6.1%). The combination bird+human+dog+pig was also found for Nyssomyia whitmani. Dogs and pigs appear to have little attractiveness for L. longipalpis. The results obtained demonstrate the eclecticism and high anthropophily of L. longipalpis and raise new questions with regard to the importance of dogs in VL epidemiology and the possible role of man as a source of infection for sand flies.

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.

Ampliación de la distribución de Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera: Psychodidae en el departamento de Caldas: potencial aumento del riesgo de leishmaniasis visceral

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Luz Adriana Acosta

2013-06-01

Full Text Available Introducción. Diversos estudios a nivel taxonómico y molecular sugieren que Lutzomyia longipalpis, principal vector de la leishmaniasis visceral en Latinoamérica, es un complejo de especies con ampliadistribución a lo largo del continente y con adaptaciones a diferentes hábitats. Objetivo. Realizar vigilancia entomológica en el área de influencia de la hidroeléctrica Miel I. Materiales y métodos. Se utilizaron trampas adhesivas en una intersección de 400 km, aproximadamente, para la captura de insectos, los cuales fueron identificados con la clave taxonómica de Youngy Duncan. Resultados. En este estudio se reporta la presencia de Lu. longipalpis en los municipios de Norcasia a una altitud de 392 msnm y en Marquetalia a 1.387 msnm; es el primer reporte a esta altura para esta especie en Colombia. Conclusiones. Se sugiere que la ampliación de la distribución geográfica y altitudinal de Lu. longipalpis en el país podría estar relacionada con la existencia del complejo de especies Lu. longipalpis, o a factores ambientales como el aumento de temperatura debido al cambio climático global que viene sucediendo en las últimas décadas. Esta última hipótesis sugeriría que se están creando nuevos hábitats propiciospara el establecimiento de Lu. longipalpis, lo cual genera un nuevo riesgo epidemiológico de posiblesnuevos focos de leishmaniasis visceral en el país.   doi: http://dx.doi.org/10.7705/biomedica.v33i2.762

Ausência da Lutzomyia longipalpis em algumas áreas de ocorrência de leishmaniose visceral no Município do Rio de Janeiro Absence of Lutzomyia longipalpis in some endemic visceral leishmaniasis areas in Rio de Janeiro municipality

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Marcos Barbosa de Souza

2003-12-01

Full Text Available Em 1977 foi diagnosticado o primeiro caso autóctone de leishmaniose visceral (LV humano no Município do Rio de Janeiro. A partir de 1980, foram diagnosticados 54 casos autóctones em diversas localidades, sendo que desde 1993 ocorreram 17 casos humanos autóctones notificados. Oito deles ocorreram no bairro de Barra de Guaratiba e o restante distribuído pelos bairros: Camorim, Colônia, Grota Funda, Grumari, Ilha de Guaratiba e Carapiá. Entre setembro de 1996 a dezembro de 1999, foram realizadas capturas de flebotomíneos em 18 localidades nas encostas do maciço da Pedra Branca, no município, e coletados 18.303 espécimes com predomínio de L. intermedia (87,33%, L. migonei (6,59%, L. longipalpis (3,10% e L. firmatoi (1,90%. A espécie L. longipalpis predominou em Barra de Guaratiba (46,80%, permanecendo ausente nas outras seis localidades onde também ocorreram casos de LV, o que sugere a participação de outras espécies tais como L. migonei e L. firmatoi, pertencentes ao mesmo grupo parafilético da espécie vetora, na cadeia de transmissão da LV na região.The first autochthonous case of human visceral leishmaniasis (VL in the Municipality of Rio de Janeiro was diagnosed in 1977. Since 1980, 54 autochthonous cases have been diagnosed in various locations, and since 1993 some 17 autochthonous human cases have been reported. Eight of these occurred in the neighborhood of Barra de Guaratiba and the others were distributed in the following neighborhoods: Camorim, Colônia, Grota Funda, Grumari, Ilha de Guaratiba, and Carapiá. From September 1996 to December 1999, phebotomine sandfly captures were performed at 18 sites on the mountainsides of the Pedra Branca Massif, in the Municipality, and a total of 18,303 specimens were collected, with a predominance of L. intermedia (87.33%, L. migonei (6.59%, L. longipalpis (3.10%, and L. firmatoi (1.90%. The species L. longipalpis predominated in Barra de Guaratiba (46.80% and was absent from the

Presence of the fire ant Solenopsis invicta (Westwood) (Hymenoptera: Formicidae) stimulates burrowing behavior by larvae of the sandfly Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae).

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Harvey, Jeffrey A; Hamilton, James G C; Ward, Richard D

2010-01-01

The sandfly Lutzomyia longipalpis (Lutz & Neiva) vectors leishmaniasis in the neotropics. Although much is known about the biology of adult flies, little is known about interactions with its natural enemies. Here, we examined behavior of larvae of L4 L.longipalpis on a soil substrate when exposed to the fire ant Solenopsis invicata (Westwood). When ants were absent, most larvae tended to remain at or close to the soil surface, but when ants were present the larvae burrowed into the soil. Sandflies seek refuges in the presence of generalist predators, thus rendering them immune to attack from many potential enemies.

Mutual reproductive dependence of distylic Cordia leucocephala (Cordiaceae) and oligolectic Ceblurgus longipalpis (Halictidae, Rophitinae) in the Caatinga.

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Milet-Pinheiro, Paulo; Schlindwein, Clemens

2010-07-01

The close relationship between distylic Cordia leucocephala and the bee Ceblurgus longipalpis, both endemic to the Caatinga, north-east Brazil, was investigated, emphasizing reproductive dependence, morphological adaptations of the partners, and pollen flow. In the municipality of Pedra, in the Caatinga of Pernambuco, the breeding system and reproductive success of C. leucocephala, its interaction with flower visitors and inter- and intramorph pollen flow were determined. The bee Ceblurgus longipalpis, the unique flower visitor and effective pollinator of self-incompatible Cordia leucocephala, presents morphological features adapted to exploit hidden pollen and nectar in the long and narrow corolla tubes. Pollen of low-level anthers is collected with hairs on prolonged mouthparts and pollen of high-level anthers with clypeus, mandibles, and labrum, showing pollen removal from both levels with the same effectiveness. In both morphs, this results in similar legitimate, i.e. intermorph cross-pollen flow. Illegitimate pollen flow to stigmas of pin flowers, however, was much higher than to stigmas of thrum flowers. Moreover, more illegitimate pollen was transported to stigmas of pin and less to those of thrum flowers when compared with legitimate pollen flow. The study reveals a one-to-one reproductive inter-dependence between both partners. Data indicate that this relationship between bee species and plant species is one of the rare cases of monolecty among bees. Monotypic Ceblurgus longipalpis, the only rophitine species of Brazil, evolved prolonged mouthparts rare among short-tongued bees that enable them to access pollen from flowers with short-level anthers hidden for bees of other species, and nectar at the base of the flower tube.

[Natural infection with Leishmania infantum chagasi in Lutzomyia (Lutzomyia) longipalpis (Diptera: Psychodidae) sandflies captured in the municipality of Janaúba, State of Minas Gerais, Brazil].

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Michalsky, Erika Monteiro; Guedes, Karla de Sena; Lara e Silva, Fabiana de Oliveira; França-Silva, João Carlos; Dias, Consuelo Latorre Fortes; Barata, Ricardo Andrade; Dias, Edelberto Santos

2011-01-01

Visceral leishmaniasis has been notified in nearly all states of Brazil, and particularly in the north of Minas Gerais, where the disease is endemic. The aim of this study was to detect natural infection of Lutzomyia longipalpis and, through the PCR/RFLP technique, identify Leishmania species found in sandflies in the municipality of Janaúba. Using light traps, 1,550 females of L. longipalpis were caught and grouped into pools of 10 specimens to be subjected to DNA extraction and amplification, by means of generic PCR and cacophony. Out of the 155 pools, six were positive for Leishmania sp., and thus the infection rate in the municipality was 3.9%. Through PCR/RFLP, the digestion pattern among the positive samples was found to be similar to that of the reference strain of Leishmania chagasi (MHOM/BR/74/PP75). The detection of natural infection associated with studies on the epidemiology of visceral leishmaniasis suggests that L. longipalpis is involved in transmission of L. infantum chagasi in Janaúba, particularly in areas of intense transmission of visceral leishmaniasis.

A comparison of molecular markers to detect Lutzomyia longipalpis naturally infected with Leishmania (Leishmania infantum

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Kárita Cláudia Freitas-Lidani

2014-07-01

Full Text Available The aim of the present study was to detect natural infection by Leishmania (Leishmania infantum in Lutzomyia longipalpis captured in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this approach, it is unnecessary to previously dissect the sandfly specimens. DNA of 280 Lu. longipalpis female specimens were extracted from the whole insects. PCR primers for kinetoplast minicircle DNA (kDNA, the mini-exon gene and the small subunit ribosomal RNA (SSU-rRNA gene of Leishmania were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively. Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in 5.3% of the cases. These data show the importance of polymerase chain reaction as a tool for investigating the molecular epidemiology of visceral leishmaniasis by estimating the risk of disease transmission in endemic areas, with the kDNA primer representing the most reliable marker for the parasite.

Influences of climate change on the potential distribution of Lutzomyia longipalpis sensu lato (Psychodidae: Phlebotominae).

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Peterson, A Townsend; Campbell, Lindsay P; Moo-Llanes, David A; Travi, Bruno; González, Camila; Ferro, María Cristina; Ferreira, Gabriel Eduardo Melim; Brandão-Filho, Sinval P; Cupolillo, Elisa; Ramsey, Janine; Leffer, Andreia Mauruto Chernaki; Pech-May, Angélica; Shaw, Jeffrey J

2017-09-01

This study explores the present day distribution of Lutzomyia longipalpis in relation to climate, and transfers the knowledge gained to likely future climatic conditions to predict changes in the species' potential distribution. We used ecological niche models calibrated based on occurrences of the species complex from across its known geographic range. Anticipated distributional changes varied by region, from stability to expansion or decline. Overall, models indicated no significant north-south expansion beyond present boundaries. However, some areas suitable both at present and in the future (e.g., Pacific coast of Ecuador and Peru) may offer opportunities for distributional expansion. Our models anticipated potential range expansion in southern Brazil and Argentina, but were variably successful in anticipating specific cases. The most significant climate-related change anticipated in the species' range was with regard to range continuity in the Amazon Basin, which is likely to increase in coming decades. Rather than making detailed forecasts of actual locations where Lu. longipalpis will appear in coming years, our models make interesting and potentially important predictions of broader-scale distributional tendencies that can inform heath policy and mitigation efforts. Copyright © 2017 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

The Gut Microbiome of the Vector Lutzomyia longipalpis Is Essential for Survival of Leishmania infantum.

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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

Tentativa de transmissão da Leishmania donovani pela picada do Lutzomyia longipalpis entre cães

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Ítalo A. Sherlock

1972-02-01

Full Text Available Os Autores apresentam dados sôbre tentativas de transmissão experimental da Leishmania donovani pela picada de Lutzomyia longipalpis entre cães. Dois cães jovens sadios foram picados respectivamente por dois e sete flebótomos ricamente infectados e não adquiriram leishmaniose.

Presence of the fire ant Solenopsis invicta (Westwood) (Hymenoptera: Formicidae) stimulates burrowing behavior by larvae of the sandfly Lutzomyia longipalpis (Lutz and Neiva) (Diptera: Psychodidae)

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Harvey, Jeffrey A. [Netherlands Institute of Ecology, Heteren (Netherlands). Dept. of Terrestrial Ecology; Hamilton, James G.C.; Ward, Richard D. [University of Keele, Staffordshire (United Kingdom). Centre for Applied Entomology and Parasitology. Dept. of Biological Sciences

2010-01-15

The sandfly Lutzomyia longipalpis (Lutz and Neiva) vectors leishmaniasis in the neotropics. Although much is known about the biology of adult flies, little is known about interactions with its natural enemies. Here, we examined behavior of larvae of L4 L. longipalpis on a soil substrate when exposed to the fire ant Solenopsis invicata (Westwood). When ants were absent, most larvae tended to remain at or close to the soil surface, but when ants were present the larvae burrowed into the soil. Sandflies seek refuges in the presence of generalist predators, thus rendering them immune to attack from many potential enemies. (author)

Presence of the fire ant Solenopsis invicta (Westwood) (Hymenoptera: Formicidae) stimulates burrowing behavior by larvae of the sandfly Lutzomyia longipalpis (Lutz and Neiva) (Diptera: Psychodidae)

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Harvey, Jeffrey A.; Hamilton, James G.C.; Ward, Richard D.

2010-01-01

The sandfly Lutzomyia longipalpis (Lutz and Neiva) vectors leishmaniasis in the neotropics. Although much is known about the biology of adult flies, little is known about interactions with its natural enemies. Here, we examined behavior of larvae of L4 L. longipalpis on a soil substrate when exposed to the fire ant Solenopsis invicata (Westwood). When ants were absent, most larvae tended to remain at or close to the soil surface, but when ants were present the larvae burrowed into the soil. Sandflies seek refuges in the presence of generalist predators, thus rendering them immune to attack from many potential enemies. (author)

Sobre a ocorrência da Lutzomyia longipalpis (Lutz & Neiva, 1912 na Ilha Grande, Estado do Rio de Janeiro, Brasil

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Nelson A. de Araújo Filho

1980-12-01

Full Text Available Os autores descrevem peta primeira vez a presença de Lutzomyia longipalpis na Praia Vermelha, praia localizada na Ilha Grande, litoral do Estado do Rio de Janeiro e acentuam a importância epidemiológica do achado.

Spatial and seasonal distribution of Lutzomyia longipalpis in Dracena, a city in the western region of the State of São Paulo, Brazil, that is endemic with visceral leishmaniasis

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Marcia Moreira Holcman

2013-12-01

Full Text Available Introduction Vector seasonality knowledge is important for monitoring and controlling of vector-borne diseases. Lutzomyia longipalpis (Lu. longipalpis is the main vector of Leishmania (Leishmania infantum Nicolle, 1908, which is the causative agent of visceral leishmaniasis in the Americas. Methods Lu. longipalpis was monitored for 3 consecutive nights each month using light traps from the Centers for Disease Control in the peridomiciles and intradomiciles of 18 residences from January 2005 to December 2012 in the urban area of Dracena, a medium-sized city located in the western region of São Paulo, Brazil. Results A total of 54,820 Lu. longipalpis specimens were collected, and the proportion of positive samples was significantly higher in the peridomiciles than in the intradomiciles (p<0.05 in all 8 years of the study, except for 2005. The vector was present in all study years in the 9 sub-regions of the city, and the male/female ratio ranged from 3.19 to 4.26. The greatest vector abundance occurred in the first semester and peaked in March, confirming its seasonality. Conclusions The maintenance of this high abundance over an 8-year surveillance period demonstrates the vector adaptation to the urban conditions of the city. These characteristics present a major challenge for preventing human and canine contact with the vector and, consequently, controlling the spread of disease.

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.

New Insights on the Inflammatory Role of Lutzomyia longipalpis Saliva in Leishmaniasis

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Prates, Deboraci Brito; Araújo-Santos, Théo; Brodskyn, Cláudia; Barral-Netto, Manoel; Barral, Aldina; Borges, Valéria Matos

2012-01-01

When an haematophagous sand fly vector insect bites a vertebrate host, it introduces its mouthparts into the skin and lacerates blood vessels, forming a hemorrhagic pool which constitutes an intricate environment of cell interactions. In this scenario, the initial performance of host, parasite, and vector “authors” will heavily influence the course of Leishmania infection. Recent advances in vector-parasite-host interaction have elucidated “co-authors” and “new roles” not yet described. We review here the stimulatory role of Lutzomyia longipalpis saliva leading to inflammation and try to connect them in an early context of Leishmania infection. PMID:22506098

New Insights on the Inflammatory Role of Lutzomyia longipalpis Saliva in Leishmaniasis

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Deboraci Brito Prates

2012-01-01

Full Text Available When an haematophagous sand fly vector insect bites a vertebrate host, it introduces its mouthparts into the skin and lacerates blood vessels, forming a hemorrhagic pool which constitutes an intricate environment of cell interactions. In this scenario, the initial performance of host, parasite, and vector “authors” will heavily influence the course of Leishmania infection. Recent advances in vector-parasite-host interaction have elucidated “co-authors” and “new roles” not yet described. We review here the stimulatory role of Lutzomyia longipalpis saliva leading to inflammation and try to connect them in an early context of Leishmania infection.

The sandfly Lutzomyia longipalpis LL5 embryonic cell line has active Toll and Imd pathways and shows immune responses to bacteria, yeast and Leishmania.

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Tinoco-Nunes, Bruno; Telleria, Erich Loza; da Silva-Neves, Monique; Marques, Christiane; Azevedo-Brito, Daisy Aline; Pitaluga, André Nóbrega; Traub-Csekö, Yara Maria

2016-04-20

Lutzomyia longipalpis is the main vector of visceral leishmaniasis in Latin America. Sandfly immune responses are poorly understood. In previous work we showed that these vector insects respond to bacterial infections by modulating a defensin gene expression and activate the Imd pathway in response to Leishmania infection. Aspects of innate immune pathways in insects (including mosquito vectors of human diseases) have been revealed by studying insect cell lines, and we have previously demonstrated antiviral responses in the L. longipalpis embryonic cell line LL5. The expression patterns of antimicrobial peptides (AMPs) and transcription factors were evaluated after silencing the repressors of the Toll pathway (cactus) and Imd pathway (caspar). AMPs and transcription factor expression patterns were also evaluated after challenge with heat-killed bacteria, heat-killed yeast, or live Leishmania. These studies showed that LL5 cells have active Toll and Imd pathways, since they displayed an increased expression of AMP genes following silencing of the repressors cactus and caspar, respectively. These pathways were also activated by challenges with bacteria, yeast and Leishmania infantum chagasi. We demonstrated that L. longipalpis LL5 embryonic cells respond to immune stimuli and are therefore a good model to study the immunological pathways of this important vector of leishmaniasis.

Environmental suitability for Lutzomyia longipalpis in a subtropical city with a recently established visceral leishmaniasis transmission cycle, Argentina.

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Berrozpe, Pablo; Lamattina, Daniela; Santini, María Soledad; Araujo, Analía Vanesa; Utgés, María Eugenia; Salomón, Oscar Daniel

2017-10-01

Visceral leishmaniasis (VL) is an endemic disease in northeastern Argentina including the Corrientes province, where the presence of the vector and canine cases of VL were recently confirmed in December 2008. The objective of this study was to assess the modelling of micro- and macro-habitat variables to evaluate the urban environmental suitability for the spatial distribution of Lutzomyia longipalpis presence and abundance in an urban scenario. Sampling of 45 sites distributed throughout Corrientes city (Argentina) was carried out using REDILA-BL minilight traps in December 2013. The sampled specimens were identified according to methods described by Galati (2003). The analysis of variables derived from the processing of satellite images (macro-habitat variables) and from the entomological sampling and surveys (micro-habitat variables) was performed using the statistical software R. Three generalised linear models were constructed composed of micro- and macro-habitat variables to explain the spatial distribution of the abundance of Lu. longipalpis and one composed of micro-habitat variables to explain the occurrence of the vector. A total of 609 phlebotominae belonging to five species were collected, of which 56% were Lu. longipalpis. In addition, the presence of Nyssomyia neivai and Migonemya migonei, which are vectors of tegumentary leishmaniasis, were also documented and represented 34.81% and 6.74% of the collections, respectively. The explanatory variable normalised difference vegetation index (NDVI) described the abundance distribution, whereas the presence of farmyard animals was important for explaining both the abundance and the occurrence of the vector. The results contribute to the identification of variables that can be used to establish priority areas for entomological surveillance and provide an efficient transfer tool for the control and prevention of vector-borne diseases.

Different host complement systems and their interactions with saliva from Lutzomyia longipalpis (Diptera, Psychodidae) and Leishmania infantum promastigotes.

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Mendes-Sousa, Antonio Ferreira; Nascimento, Alexandre Alves Sousa; Queiroz, Daniel Costa; Vale, Vladimir Fazito; Fujiwara, Ricardo Toshio; Araújo, Ricardo Nascimento; Pereira, Marcos Horácio; Gontijo, Nelder Figueiredo

2013-01-01

Lutzomyia longipalpis is the vector of Leishmania infantum in the New World, and its saliva inhibits classical and alternative human complement system pathways. This inhibition is important in protecting the insect´s midgut from damage by the complement. L. longipalpis is a promiscuous blood feeder and must be protected against its host's complement. The objective of this study was to investigate the action of salivary complement inhibitors on the sera of different host species, such as dogs, guinea pigs, rats and chickens, at a pH of 7.4 (normal blood pH) and 8.15 (the midgut pH immediately after a blood meal). We also investigated the role of the chicken complement system in Leishmania clearance in the presence and absence of vector saliva. The saliva was capable of inhibiting classical pathways in dogs, guinea pigs and rats at both pHs. The alternative pathway was not inhibited except in dogs at a pH of 8.15. The chicken classical pathway was inhibited only by high concentrations of saliva and it was better inhibited by the midgut contents of sand flies. Neither the saliva nor the midgut contents had any effect on the avian alternative pathway. Fowl sera killed L. infantum promastigotes, even at a low concentration (2%), and the addition of L. longipalpis saliva did not protect the parasites. The high body temperature of chickens (40°C) had no effect on Leishmania viability during our assays. Salivary inhibitors act in a species-specific manner. It is important to determine their effects in the natural hosts of Leishmania infantum because they act on canid and rodent complements but not on chickens (which do not harbour the parasite). Moreover, we concluded that the avian complement system is the probable mechanism through which chickens eliminate Leishmania and that their high body temperature does not influence this parasite.

Pheromone gland development and pheromone production in lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae).

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Spiegel, Carolina N; Batista-Pereira, Luciane G; Bretas, Jorge A C; Eiras, Alvaro E; Hooper, Antony M; Peixoto, Alexandre A; Soares, Maurilio J

2011-05-01

The sand fly Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae: Phlebotominae) is the main vector of American visceral leishmaniasis. Adult males produce a terpenoid sex pheromone that in some cases also acts as male aggregation pheromone. We have analyzed the correlation between male pheromone production levels and pheromone gland cell morphogenesis after adult emergence from pupae. The abdominal tergites of L. longipalpis males were dissected and fixed in glutaraldehyde for transmission electron microscopy, or the pheromone was extracted in analytical grade hexane. Pheromone chemical analysis was carried out at 3- to 6-h intervals during the first 24 h after emergence and continued daily until the seventh day. All extracts were analyzed by gas chromatography. For the morphological analysis, we used insects collected at 0-6, 9-12, 12-14, and 96 h after emergence. Ultrastructural data from 0- to 6-h-old adult males revealed smaller pheromone gland cells with small microvilli at the end apparatus. Lipid droplets and peroxisomes were absent or very rare, but a large number of mitochondria could be seen. Lipid droplets started to appear in the gland cells cytoplasm approximately 9 h after adult emergence, and their number and size increased with age, together with the presence of several peroxisomes, suggesting a role for these organelles in pheromone biosynthesis. At 12-15 h after emergence, the lipid droplets were mainly distributed near the microvilli but were smaller than those in mature older males (4 d old). Pheromone biosynthesis started around 12 h after emergence and increased continuously during the first 3 d, stabilizing thereafter, coinciding with the period when males are more able to attract females.

The distribution pattern of Lutzomyia longipalpis (Diptera: Psychodidae in the peridomiciles of a sector with canine and human visceral leishmaniasis transmission in the municipality of Dracena, São Paulo, Brazil

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Osias Rangel

2012-03-01

Full Text Available The specimen distribution pattern of a species can be used to characterise a population of interest and also provides area-specific guidance for pest management and control. In the municipality of Dracena, in the state of São Paulo, we analysed 5,889 Lutzomyia longipalpis specimens collected from the peridomiciles of 14 houses in a sector where American visceral leishmaniasis (AVL is transmitted to humans and dogs. The goal was to analyse the dispersion and a theoretical fitting of the species occurrence probability. From January-December 2005, samples were collected once per week using CDC light traps that operated for 12-h periods. Each collection was considered a sub-sample and was evaluated monthly. The standardised Morisita index was used as a measure of dispersion. Adherence tests were performed for the log-series distribution. The number of traps was used to adjust the octave plots. The quantity of Lu. longipalpis in the sector was highly aggregated for each month of the year, adhering to a log-series distribution for 11 of the 12 months analysed. A sex-stratified analysis demonstrated a pattern of aggregated dispersion adjusted for each month of the year. The classes and frequencies of the traps in octaves can be employed as indicators for entomological surveillance and AVL control.

The distribution pattern of Lutzomyia longipalpis (Diptera: Psychodidae) in the peridomiciles of a sector with canine and human visceral leishmaniasis transmission in the municipality of Dracena, São Paulo, Brazil.

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Rangel, Osias; Sampaio, Susy Mary Perpetuo; Ciaravolo, Ricardo Mario de Carvalho; Holcman, Marcia Moreira

2012-03-01

The specimen distribution pattern of a species can be used to characterise a population of interest and also provides area-specific guidance for pest management and control. In the municipality of Dracena, in the state of São Paulo, we analysed 5,889 Lutzomyia longipalpis specimens collected from the peridomiciles of 14 houses in a sector where American visceral leishmaniasis (AVL) is transmitted to humans and dogs. The goal was to analyse the dispersion and a theoretical fitting of the species occurrence probability. From January-December 2005, samples were collected once per week using CDC light traps that operated for 12-h periods. Each collection was considered a sub-sample and was evaluated monthly. The standardised Morisita index was used as a measure of dispersion. Adherence tests were performed for the log-series distribution. The number of traps was used to adjust the octave plots. The quantity of Lu. longipalpis in the sector was highly aggregated for each month of the year, adhering to a log-series distribution for 11 of the 12 months analysed. A sex-stratified analysis demonstrated a pattern of aggregated dispersion adjusted for each month of the year. The classes and frequencies of the traps in octaves can be employed as indicators for entomological surveillance and AVL control.

Avaliação da eficiência de deltametrina (K-othrine CE no controle de Lutzomyia longipalpis (Diptera: Psychodidae, no município de Santa Rita, Paraíba, Brasil

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Carlos Brisola Marcondes

1993-03-01

Full Text Available Deltametrina em concentrado emulsionável foi aplicada em doses de 12,5, 25,0 e 50,0mg/m², em domicílios de área próxima do litoral da Paraíba, onde eram relatados casos esporádicos de leishmaniose visceral. Houve uma redução marcante nas populações de vários artrópodes, incluindo Lutzotnyia longipalpis. Este inseto, no entanto, foi encontrado novamente em contato com paredes tratadas, 14 e 21 dias após a pulverização. A análise estatística indicou controle significativo em apenas dois períodos de quatro semanas, com extrema irregularidade nas quantidades capturadas.Deltamethrin in emulsion concentrate was applied in doses of 12.5, 25.0 and 50.0mg/m², in households near the littoral of the State of Paraíba, where sporadic cases of visceral leishmaniasis were reported. There was a remarkable decrease in populations of several arthropods, including Lutzomyia longipalpis. This insect, however, was found again in some treated walls, 14 and 21 days after spraying. Statistical analysis indicated significant control for onfy two four-weeks periods, with extreme irregularity in the quantity captured.

Atividade inseticida in vitro do óleo de sementes de nim sobre Lutzomyia longipalpis (Diptera: Psychodidae In vitro insecticidal activity of seed neem oil on Lutzomyia longipalpis (Diptera: Psychodidae

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Michelline V. Maciel

2010-03-01

Full Text Available Lutzomyia longipalpis é o principal vetor da Leishmaniose visceral no Brasil. O objetivo deste trabalho foi avaliar o efeito do óleo de sementes de nim (Azadirachta indica sobre ovos, larvas e adultos do vetor. Os insetos foram capturados no campo e mantidos no laboratório a ± 27 °C e 80% de umidade relativa. Cinco tratamentos com diferentes concentrações foram realizados, usando-se dois controles negativos, um com água destilada e outro com Tween 80 (3% e um controle positivo com cipermetrina. Os ovos foram borrifados com o óleo em diferentes concentrações e avaliou-se o número de larvas eclodidas por 10 dias consecutivos. A mortalidade das larvas foi observada até a pupação, e a mortalidade dos adultos foi observada após 24, 48, e 72 horas. A análise estatística foi feita pelo teste de Tukey a 5% de probabilidade. No teste com ovos, a maior concentração obteve 65,16 ± 3,24% de eficácia. O teste com larvas apresentou 67,75 ± 2,21% de eficácia na concentração de 100 mg.mL-1. Com adultos, a eficácia na concentração de 100 mg.mL-1 foi de 96,64 ± 4,11%, após 24 horas. A análise fitoquímica revelou a presença de triterpenos. Esses resultados demonstram o potencial uso desse óleo no controle deste vetor.Lutzomyia longipalpis is the main vector of visceral leishmaniasis in Brazil. The objective was to evaluate the effect of oil from (Azadirachta indica neem seeds on eggs, larvae and adults of the vector. The insects were captured in the field and kept in the laboratory at ± 27 °C and 80% relative humidity. Five treatments with different concentrations were performed using two negative controls (distilled water and Tween 80 and a positive control. The eggs were sprayed with the oil at different concentrations and the number of hatched larvae evaluated for 10 days. Mortality of larvae was observed to pupation and adult mortality was observed after 24, 48, and 72 hours. Statistical analysis was performed by Tukey test

Different host complement systems and their interactions with saliva from Lutzomyia longipalpis (Diptera, Psychodidae and Leishmania infantum promastigotes.

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Antonio Ferreira Mendes-Sousa

Full Text Available BACKGROUND: Lutzomyia longipalpis is the vector of Leishmania infantum in the New World, and its saliva inhibits classical and alternative human complement system pathways. This inhibition is important in protecting the insect´s midgut from damage by the complement. L. longipalpis is a promiscuous blood feeder and must be protected against its host's complement. The objective of this study was to investigate the action of salivary complement inhibitors on the sera of different host species, such as dogs, guinea pigs, rats and chickens, at a pH of 7.4 (normal blood pH and 8.15 (the midgut pH immediately after a blood meal. We also investigated the role of the chicken complement system in Leishmania clearance in the presence and absence of vector saliva. RESULTS: The saliva was capable of inhibiting classical pathways in dogs, guinea pigs and rats at both pHs. The alternative pathway was not inhibited except in dogs at a pH of 8.15. The chicken classical pathway was inhibited only by high concentrations of saliva and it was better inhibited by the midgut contents of sand flies. Neither the saliva nor the midgut contents had any effect on the avian alternative pathway. Fowl sera killed L. infantum promastigotes, even at a low concentration (2%, and the addition of L. longipalpis saliva did not protect the parasites. The high body temperature of chickens (40°C had no effect on Leishmania viability during our assays. CONCLUSION: Salivary inhibitors act in a species-specific manner. It is important to determine their effects in the natural hosts of Leishmania infantum because they act on canid and rodent complements but not on chickens (which do not harbour the parasite. Moreover, we concluded that the avian complement system is the probable mechanism through which chickens eliminate Leishmania and that their high body temperature does not influence this parasite.

A temporal comparison of sex-aggregation pheromone gland content and dynamics of release in three members of the Lutzomyia longipalpis (Diptera: Psychodidae species complex.

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Mikel A González

2017-12-01

Full Text Available Lutzomyia longipalpis is the South American vector of Leishmania infantum, the etiologic agent of visceral leishmaniasis (VL. Male L. longipalpis produce a sex-aggregation pheromone that is critical in mating, yet very little is known about its accumulation over time or factors involved in release. This laboratory study aimed to compare accumulation of pheromone over time and determine factors that might influence release in three members of the L. longipalpis species complex.We investigated male sex-aggregation pheromone gland content at different ages and the release rate of pheromone in the presence or absence of females under different light conditions by gas chromatography-mass spectrometry (GC-MS. Pheromone gland content was determined by extraction of whole males and pheromone release rate was determined by collection of headspace volatiles. Pheromone gland content appeared age-related and pheromone began to accumulate between 6 to 12 h post eclosion and gradually increased until males were 7-9 days old. The greatest amount was detected in 9-day old Campo Grande males ((S-9-methylgermacrene-B; X ± SE: 203.5 ± 57.4 ng/male followed by Sobral 2S males (diterpene; 199.9 ± 34.3 and Jacobina males ((1S,3S,7R-3-methyl-α-himachalene; 128.8 ± 30.3 at 7 days old. Pheromone release was not continuous over time. During a 4-hour period, the greatest quantities of pheromone were released during the first hour, when wing beating activity was most intense. It was then substantially diminished for the remainder of the time. During a 24 h period, 4-5 day old male sand flies released approximately 63 ± 11% of the pheromone content of their glands, depending on the chemotype. The presence of females significantly increased pheromone release rate. The light regime under which the sand flies were held had little influence on pheromone release except on Sobral 2S chemotype.Accumulation of pheromone appears to occur at different rates in the different

A temporal comparison of sex-aggregation pheromone gland content and dynamics of release in three members of the Lutzomyia longipalpis (Diptera: Psychodidae) species complex.

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González, Mikel A; Bandi, Krishna K; Bell, Melissa J; Brazil, Reginaldo P; Dilger, Erin; Guerrero, Angel; Courtenay, Orin; Hamilton, James G C

2017-12-01

Lutzomyia longipalpis is the South American vector of Leishmania infantum, the etiologic agent of visceral leishmaniasis (VL). Male L. longipalpis produce a sex-aggregation pheromone that is critical in mating, yet very little is known about its accumulation over time or factors involved in release. This laboratory study aimed to compare accumulation of pheromone over time and determine factors that might influence release in three members of the L. longipalpis species complex. We investigated male sex-aggregation pheromone gland content at different ages and the release rate of pheromone in the presence or absence of females under different light conditions by gas chromatography-mass spectrometry (GC-MS). Pheromone gland content was determined by extraction of whole males and pheromone release rate was determined by collection of headspace volatiles. Pheromone gland content appeared age-related and pheromone began to accumulate between 6 to 12 h post eclosion and gradually increased until males were 7-9 days old. The greatest amount was detected in 9-day old Campo Grande males ((S)-9-methylgermacrene-B; X ± SE: 203.5 ± 57.4 ng/male) followed by Sobral 2S males (diterpene; 199.9 ± 34.3) and Jacobina males ((1S,3S,7R)-3-methyl-α-himachalene; 128.8 ± 30.3) at 7 days old. Pheromone release was not continuous over time. During a 4-hour period, the greatest quantities of pheromone were released during the first hour, when wing beating activity was most intense. It was then substantially diminished for the remainder of the time. During a 24 h period, 4-5 day old male sand flies released approximately 63 ± 11% of the pheromone content of their glands, depending on the chemotype. The presence of females significantly increased pheromone release rate. The light regime under which the sand flies were held had little influence on pheromone release except on Sobral 2S chemotype. Accumulation of pheromone appears to occur at different rates in the different chemotypes

Occurrence of Lutzomyia longipalpis Lutz & Neiva 1912 and Cerdocyon thous Linnaeus 1977, in a visceral leishmaniasis endemic area in Brazil.

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Araujo Soares, Maria Regiane; Lopes Antunes, Jadson Emanuel; de Mendonça, Ivete Lopes; Lima, Rogério Nora; Nery Costa, Carlos Henrique

2017-10-01

Cerdocyon thous presents a wide geographic distribution in Brazil and its role as a possible Leishmania infantum reservoir in a visceral leishmaniasis (VL) transmission cycle regardless of dogs (Canis familiaris) has been discussed. From this perspective, this work describes the occurrence and use of the habitat by Cerdocyon thous in a Lutzomyia longipalpis occurrence area Teresina (Piaui - Brazil), VL endemic region. Three specimens of C. thous were monitored with the use of radio telemetry and trails and footprints, seeking to find possible natural dens in order to collect the sanflies from the site. Luminous CDC and Damasceno traps were simultaneously installed at the visited sites, where two specimens of L. longipalpis and one L. termitophila were captured. The identification of the dens and trails, allows us to infer that the dens are not used only by the C. thous. Finding the VL vector in natural C. thous natural dens, reinforces the hypothesis of transmission of Le. infantum in the outskirts of the large urban centers, in a cycle that independs from dogs. Copyright © 2017 Elsevier B.V. All rights reserved.

First Record of Lutzomyia (Lutzomyia) longipalpis (Diptera: Psychodidae: Phlebotominae) on the Trinational Frontier (Brazil-Peru-Bolivia) of South-Western Amazonia.

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Borges, Diones Antonio; Molina, Silvia Maria Guerra; Pinto, Mara Cristina; Galati, Eunice Aparecida Bianchi; Cesario, Manuel; Ortiz, Dennys Ghenry Samillan

2017-09-01

In South America, the main sand fly species involved in the transmission of Leishmania infantum chagasi (Cunha & Chagas, 1937), etiological agent of the visceral leishmaniasis (VL), is Lutzomyia longipalpis (Lutz & Neiva, 1912). The species has been recorded in Colombia, Venezuela, Bolivia, Argentina, Paraguay, Uruguay, and Brazil, where it is recorded in 24 of the 27 Brazilian states, except Acre, Amazonas, and Santa Catarina. Collections were carried out for one year (April 2013 to March 2014) using modified CDC light traps in different environments in Assis Brasil municipality, state of Acre. Two males of Lu. longipalpis were found in peridomiciliary location in a peri-urban area. This is the first record of the species in Acre. This finding may be considered by the health agencies located in the trinational frontier, and new collections are needed to evaluate the real distribution of the species. © 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

Identification of Secreted Proteins Involved in Nonspecific dsRNA-Mediated Lutzomyia longipalpis LL5 Cell Antiviral Response

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Andrea Martins-da-Silva

2018-01-01

Full Text Available Hematophagous insects transmit infectious diseases. Sand flies are vectors of leishmaniasis, but can also transmit viruses. We have been studying immune responses of Lutzomyia longipalpis, the main vector of visceral leishmaniasis in the Americas. We identified a non-specific antiviral response in L. longipalpis LL5 embryonic cells when treated with non-specific double-stranded RNAs (dsRNAs. This response is reminiscent of interferon response in mammals. We are investigating putative effectors for this antiviral response. Secreted molecules have been implicated in immune responses, including interferon-related responses. We conducted a mass spectrometry analysis of conditioned medium from LL5 cells 24 and 48 h after dsRNA or mock treatment. We identified 304 proteins. At 24 h, 19 proteins had an abundance equal or greater than 2-fold change, while the levels of 17 proteins were reduced when compared to control cells. At the 48 h time point, these numbers were 33 and 71, respectively. The two most abundant secreted peptides at 24 h in the dsRNA-transfected group were phospholipid scramblase, an interferon-inducible protein that mediates antiviral activity, and forskolin-binding protein (FKBP, a member of the immunophilin family, which mediates the effect of immunosuppressive drugs. The transcription profile of most candidates did not follow the pattern of secreted protein abundance.

American visceral leishmaniasis dissociated from Lutzomyia longipalpis (Diptera, Psychodidae) in the State of Espírito Santo, Brazil

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Pinto,Israel de Souza; Santos,Claudiney Biral dos; Grimaldi Jr.,Gabriel; Ferreira,Adelson Luiz; Falqueto,Aloísio

2010-01-01

The occurrence of American visceral leishmaniasis in the State of Espírito Santo, Brazil has always been associated with the presence of the Lutzomyia longipalpis vector. The geographic distribution of this vector in this state is related to the presence of specific geoclimatic characteristics, such as a dry climate, low elevations (< 450m), steep slopes and rocky outcrops. The occurrence of human autochthonous cases of American visceral leishmaniasis in municipalities without these geoclimat...

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

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1981-10-01

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

Distribuição espacial de Lutzomyia longipalpis (Lutz & Neiva, 1912) e Lutzomyia cruzi (Mangabeira, 1938) no estado de Mato Grosso Spatial distribution of Lutzomyia longipalpis (Lutz & Neiva, 1912) and Lutzomyia cruzi (Mangabeira, 1938) in the State of Mato Grosso

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Nanci Akemi Missawa; Giovana Belem Moreira Lima

2006-01-01

A leishmaniose visceral é considerada atualmente uma doença emergente e reemergente, em zonas rurais e urbanas, tanto em área domiciliar quanto peridomiciliar. Este trabalho teve como objetivo verificar a distribuição espacial de Lutzomyia longipalpis e Lutzomyia cruzi no Estado de Mato Grosso. Os dados de 1996 a 2004 foram obtidos junto ao Laboratório de Entomologia, cujas capturas foram realizadas com armadilha de luz CDC. Foram pesquisados 68 dos 139 municípios do estado. Lutzomyia longipa...

Primeiro encontro de Lutzomyia longipalpis (Lutz & Neiva, 1912 na área urbana de Uberlândia, MG, concomitante com o relato de primeiro caso autóctone de leishmaniose visceral humana First finding of Lutzomyia longipalpis (Lutz & Neiva, 1912 in the urban area of Uberlândia, MG, concomitant with the first reported autochthonous case of human visceral leishmaniasis

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Márcia Beatriz Cardoso de Paula

2008-06-01

Full Text Available Relata-se a primeira ocorrência do vetor da leishmaniose visceral, Lutzomyia longipalpis, na área urbana de Uberlândia, estado de Minas Gerais e o primeiro caso de leishmaniose visceral humana autóctone no município, notificado ao Centro de Controle de Zoonoses, por meio da Vigilância Epidemiológica da Secretaria Municipal de Saúde. Discute-se a importância deste encontro na transmissão da doença nessa área.The first occurrence of the vector for visceral leishmaniasis, Lutzomyia longipalpis, in the urban area of Uberlândia, State of Minas Gerais, and the first autochthonous case of human visceral leishmaniasis recorded in the same locality are reported. These were notified to the Zoonosis Control Center, through the Epidemiological Surveillance sector of the Municipal Health Department. The importance of these findings regarding transmission of the disease in this area is discussed.

Detection of Leishmania infantum in naturally infected Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) and Canis familiaris in Misiones, Argentina: the first report of a PCR-RFLP and sequencing-based confirmation assay.

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Acardi, Soraya Alejandra; Liotta, Domingo Javier; Santini, María Soledad; Romagosa, Carlo Mariano; Salomón, Oscar Daniel

2010-09-01

In this study, a genotypification of Leishmania was performed using polimerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing techniques to identify species of Leishmania parasites in phlebotomine sand flies and dogs naturally infected. Between January-February of 2009, CDC light traps were used to collect insect samples from 13 capture sites in the municipality of Posadas, which is located in the province of Misiones of Argentina. Sand flies identified as Lutzomyia longipalpis were grouped into 28 separate pools for molecular biological analysis. Canine samples were taken from lymph node aspirates of two symptomatic stray animals that had been positively diagnosed with canine visceral leishmaniasis. One vector pool of 10 sand flies (1 out of the 28 pools tested) and both of the canine samples tested positively for Leishmania infantum by PCR and RFLP analysis. PCR products were confirmed by sequencing and showed a maximum identity with L. infantum. Given that infection was detected in one out of the 28 pools and that at least one infected insect was infected, it was possible to infer an infection rate at least of 0.47% for Lu. longipalpis among the analyzed samples. These results contribute to incriminate Lu. longipalpis as the vector of L. infantum in the municipality of Posadas, where cases of the disease in humans and dogs have been reported since 2005.

Expression, purification, crystallization and crystallographic study of Lutzomyia longipalpis LJL143.

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Kelleher, Alan; Liu, Zhuyun; Seid, Christopher A; Zhan, Bin; Asojo, Oluwatoyin A

2015-07-01

Leishmaniasis is a neglected vector-borne disease with a global prevalence of over 12 million cases and 59,000 annual deaths. Transmission of the parasite requires salivary proteins, including LJL143 from the New World sandfly Lutzomyia longipalpis. LJL143 is a known marker of sandfly exposure in zoonotic hosts. LJL143 was crystallized from soluble protein expressed using Pichia pastoris. X-ray data were collected to 2.6 Å resolution from orthorhombic crystals belonging to space group P2(1)2(1)2(1), with average unit-cell parameters a = 57.39, b = 70.24, c = 79.58 Å. The crystals are predicted to have a monomer in the asymmetric unit, with an estimated solvent content of 48.5%. LJL143 has negligible homology to any reported structures, so the phases could not be determined by molecular replacement. All attempts at S-SAD failed and future studies include experimental phase determination using heavy-atom derivatives.

Dispersal of Lutzomyia longipalpis and expansion of canine and human visceral leishmaniasis in São Paulo State, Brazil.

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Oliveira, Agda Maria; Vieira, Carolina Portugal; Dibo, Margareth Regina; Guirado, Marluci Monteiro; Rodas, Lilian Aparecida Colebrusco; Chiaravalloti-Neto, Francisco

2016-12-01

Visceral leishmaniasis (VL), a neglected disease, is a serious public health problem that affects millions of people worldwide. The objectives of the study were to evaluate the sensitivity of Lutzomyia longipalpis and canine VL (CVL) autochthony early detection and describe the spatial and temporal dispersal of vector and expansion of VL in a Brazilian state. We obtained data on the leishmaniasis vector and VL cases in São Paulo State (SP), Brazil, from the Division of Endemic Disease Control and from the Epidemiological Surveillance Center of the São Paulo State Department of Health. Data were analyzed for 645 municipalities and 63 microregions and presented as thematic and flow maps. Following the verified presence of L. longipalpis in Araçatuba in 1997, the first autochthonous cases of canine VL (CVL) (1998) and of human VL (HVL) (1999) in São Paulo were reported, both in Araçatuba. From 1997 to 2014, the urban presence of the leishmaniasis vector was verified in 167 (25.9%) municipalities with cases of CVL reported in 108 (16.7%) and cases of HVL in 84 (13%). The sensitivities for vector presence early detection in relation to the identification of CVL and HVL autochthony were, respectively, equal to 76.4 and 92.5%. The sensitivity for CVL autochthony early detection in relation to the HVL autochthony identification was 75.8%. Vector dispersal and expansion of CVL and HVL were from the northwest to the southeast of the state, primarily flanking the Marechal Rondon highway at a constant rate of progression of 10, seven, and six new municipalities affected per year, respectively. We concluded that the sensitivity for vector presence and CVL autochthony presented reasonable accuracy and most of the time the vector presence and, specially, the CVL and HVL autochthony were identified in the main cities of the microregions of SP. Vector dispersal and expansion of VL started in 1997 near the state border of SP with the state of Mato Grosso do Sul. It has advanced

Synthetic sex pheromone in a long-lasting lure attracts the visceral leishmaniasis vector, Lutzomyia longipalpis, for up to 12 weeks in Brazil.

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Daniel P Bray

2014-03-01

Full Text Available Current control methodologies have not prevented the spread of visceral leishmaniasis (VL across Brazil. Here, we describe the development of a new tool for controlling the sand fly vector of the disease: a long-lasting lure, which releases a synthetic male sex pheromone, attractive to both sexes of Lutzomyia longipalpis. This device could be used to improve the effectiveness of residual insecticide spraying as a means of sand fly control, attracting L. longipalpis to insecticide-treated animal houses, where they could be killed in potentially large numbers over a number of weeks. Different lure designs releasing the synthetic pheromone (±-9-methylgermacrene-B (CAS 183158-38-5 were field-tested in Araçatuba, São Paulo (SP. Experiments compared numbers of sand flies caught overnight in experimental chicken sheds with pheromone lures, to numbers caught in control sheds without pheromone. Prototype lures, designed to last one night, were first used to confirm the attractiveness of the pheromone in SP, and shown to attract significantly more flies to test sheds than controls. Longer-lasting lures were tested when new, and at fortnightly intervals. Lures loaded with 1 mg of pheromone did not attract sand flies for more than two weeks. However, lures loaded with 10 mg of pheromone, with a releasing surface of 15 cm2 or 7.5 cm2, attracted female L. longipalpis for up to ten weeks, and males for up to twelve weeks. Approximately five times more sand flies were caught with 7.5 cm2 10 mg lures when first used than occurred naturally in non-experimental chicken resting sites. These results demonstrate that these lures are suitably long-lasting and attractive for use in sand fly control programmes in SP. To our knowledge, this is the first sex pheromone-based technology targeting an insect vector of a neglected human disease. Further studies should explore the general applicability of this approach for combating other insect-borne diseases.

Leishmaniose visceral americana dissociada da presença de Lutzomyia longipalpis (Diptera, Psychodidae) no Estado do Espírito Santo, Brasil

OpenAIRE

Pinto, Israel de Souza; Santos, Claudiney Biral dos; Grimaldi Jr., Gabriel; Ferreira, Adelson Luiz; Falqueto, Aloísio

2010-01-01

The occurrence of American visceral leishmaniasis in the State of Espírito Santo, Brazil has always been associated with the presence of the Lutzomyia longipalpis vector. The geographic distribution of this vector in this state is related to the presence of specific geoclimatic characteristics, such as a dry climate, low elevations (< 450m), steep slopes and rocky outcrops. The occurrence of human autochthonous cases of American visceral leishmaniasis in municipalities without these geoclimat...

The Lutzomyia longipalpis complex: a brief natural history of aggregation-sex pheromone communication.

Science.gov (United States)

Spiegel, Carolina N; Dias, Denise B Dos Santos; Araki, Alejandra S; Hamilton, James G C; Brazil, Reginaldo P; Jones, Théresa M

2016-11-14

In this paper we review the natural history of pheromone communication and the current diversity of aggregation-sex pheromones in the sand fly Lutzomyia longipalpis. This species complex is the main vector of Leishmania infantum, the agent of visceral leishmaniasis in the Americas. The identification of variation in pheromone chemotypes combined with molecular and sound analyses have all contributed to our understanding of the extent of divergence among cryptic members of this complex. The importance of chemical signals as pre-mating barriers and drivers of speciation is discussed. Moreover, the importance of aggregation-sex pheromones as sexually selected signals is highlighted with evidence from the literature suggesting their potential role in species and mate recognition as well as mate assessment. The distinct evolutionary forces possibly involved are briefly reviewed and discussed in the context of this intriguing insect.

Indicadores de sensibilidad de una cepa experimental de Lutzomyia longipalpis (Diptera: Psychodidae a tres insecticidas de uso en salud pública en Colombia

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Catalina Marceló

2014-12-01

Conclusión. Se estableció la línea base de la mortalidad frente a tres insecticidas en una cepa sensible del vector L. longipalpis. Estos indicadores permitirán establecer comparaciones con poblaciones del vector expuestas regular o esporádicamente a medidas de control químico y detectar, así, cambios en la sensibilidad de esta especie a los insecticidas.

Freqüência horária e sazonalidade de Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae na Ilha de São Luís, Maranhão, Brasil

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Rebêlo José Manuel Macário

2001-01-01

Full Text Available A distribuição sazonal e horária de Lutzomyia longipalpis foi estudada nos ambientes peri e intradomiciliar de duas localidades da Ilha de São Luís, estado do Maranhão. Os 11.200 exemplares capturados foram atraídos por quatro armadilhas CDC nos anos de 1996 e 1997, mensalmente, das 18h às 6h. L. longipalpis comportou-se como uma espécie anual, tendo sido encontrada em alta freqüência em todos os meses do ano, tendendo a ser mais abundante no período chuvoso (57,2% do que no seco (42,8%. As maiores freqüências foram observadas nos meses de janeiro e abril, no período chuvoso, e em julho e novembro, no período seco. Foi encontrada a noite inteira, porém foi mais freqüente entre 18h e 22h no peridomicílio, e entre 20h e 2h no intradomicílio.

Ausência da Lutzomyia longipalpis em algumas áreas de ocorrência de leishmaniose visceral no Município do Rio de Janeiro

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Marcos Barbosa de Souza

2003-12-01

Full Text Available Em 1977 foi diagnosticado o primeiro caso autóctone de leishmaniose visceral (LV humano no Município do Rio de Janeiro. A partir de 1980, foram diagnosticados 54 casos autóctones em diversas localidades, sendo que desde 1993 ocorreram 17 casos humanos autóctones notificados. Oito deles ocorreram no bairro de Barra de Guaratiba e o restante distribuído pelos bairros: Camorim, Colônia, Grota Funda, Grumari, Ilha de Guaratiba e Carapiá. Entre setembro de 1996 a dezembro de 1999, foram realizadas capturas de flebotomíneos em 18 localidades nas encostas do maciço da Pedra Branca, no município, e coletados 18.303 espécimes com predomínio de L. intermedia (87,33%, L. migonei (6,59%, L. longipalpis (3,10% e L. firmatoi (1,90%. A espécie L. longipalpis predominou em Barra de Guaratiba (46,80%, permanecendo ausente nas outras seis localidades onde também ocorreram casos de LV, o que sugere a participação de outras espécies tais como L. migonei e L. firmatoi, pertencentes ao mesmo grupo parafilético da espécie vetora, na cadeia de transmissão da LV na região.

Ausência da Lutzomyia longipalpis em algumas áreas de ocorrência de leishmaniose visceral no Município do Rio de Janeiro

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Souza Marcos Barbosa de

2003-01-01

Full Text Available Em 1977 foi diagnosticado o primeiro caso autóctone de leishmaniose visceral (LV humano no Município do Rio de Janeiro. A partir de 1980, foram diagnosticados 54 casos autóctones em diversas localidades, sendo que desde 1993 ocorreram 17 casos humanos autóctones notificados. Oito deles ocorreram no bairro de Barra de Guaratiba e o restante distribuído pelos bairros: Camorim, Colônia, Grota Funda, Grumari, Ilha de Guaratiba e Carapiá. Entre setembro de 1996 a dezembro de 1999, foram realizadas capturas de flebotomíneos em 18 localidades nas encostas do maciço da Pedra Branca, no município, e coletados 18.303 espécimes com predomínio de L. intermedia (87,33%, L. migonei (6,59%, L. longipalpis (3,10% e L. firmatoi (1,90%. A espécie L. longipalpis predominou em Barra de Guaratiba (46,80%, permanecendo ausente nas outras seis localidades onde também ocorreram casos de LV, o que sugere a participação de outras espécies tais como L. migonei e L. firmatoi, pertencentes ao mesmo grupo parafilético da espécie vetora, na cadeia de transmissão da LV na região.

Host modulation by a parasite: how Leishmania infantum modifies the intestinal environment of Lutzomyia longipalpis to favor its development.

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Vania Cristina Santos

Full Text Available Some reports have described the interference of Leishmania on sand flies physiology, and such behavior most likely evolved to favor the development and transmission of the parasite. Most of these studies showed that Leishmania could modulate the level of proteases in the midgut after an infective blood meal, and decreased proteolytic activity is indeed beneficial for the development of promastigotes in the gut of sand flies. In the present study, we performed a detailed investigation of the intestinal pH in Lutzomyia longipalpis females naturally infected with Leishmania infantum and investigated the production of trypsin by these insects using different approaches. Our results allowed us to propose a mechanism by which these parasites interfere with the physiology of L. longipalpis to decrease the production of proteolytic enzymes. According to our hypothesis L. infantum promastigotes indirectly interfere with the production of trypsin by modulating the mechanism that controls the intestinal pH via the action of a yet non-identified substance released by promastigote forms inside the midgut. This substance is not an acid, whose action would be restrict on to release H+ to the medium, but is a substance that is able to interfere with midgut physiology through a mechanism involving pH control. According to our hypothesis, as the pH decreases, the proteolytic enzymes efficiency is also reduced, leading to a decline in the supply of amino acids to the enterocytes: this decline reduces the stimulus for protease production because it is regulated by the supply of amino acids, thus leading to a delay in digestion.

Distribuição espacial de Lutzomyia longipalpis (Lutz & Neiva, 1912) e Lutzomyia cruzi (Mangabeira, 1938) no estado de Mato Grosso

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Missawa, Nanci Akemi; Lima, Giovana Belem Moreira

2006-01-01

A leishmaniose visceral é considerada atualmente uma doença emergente e reemergente, em zonas rurais e urbanas, tanto em área domiciliar quanto peridomiciliar. Este trabalho teve como objetivo verificar a distribuição espacial de Lutzomyia longipalpis e Lutzomyia cruzi no Estado de Mato Grosso. Os dados de 1996 a 2004 foram obtidos junto ao Laboratório de Entomologia, cujas capturas foram realizadas com armadilha de luz CDC. Foram pesquisados 68 dos 139 municípios do estado. Lutzomyia longipa...

Leg loss in Lutzomyia longipalpis (Diptera: Psychodidae) due to pyrethroid exposure: Toxic effect or defense by autotomy?

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Santamaría, E; Cabrera, O L; Avendaño, J; Pardo, R H

2016-01-01

Phlebotomine sandflies lose their legs after exposure to pyrethroids. In some insects leg loss helps to defend them from intoxication and predation, a phenomenon known as autotomy. A field observation has shown that sandflies that have lost some legs are still able to blood-feed. The aims of the study were to determine whether leg loss in sandflies, after exposure to deltamethrin, is due to autotomy and to establish the effect of the leg loss on blood-feeding. Two experiments were carried out with Lutzomyia longipalpis: (i) Females were individually exposed to a sublethal time of deltamethrin and mortality and the number of leg loss were recorded; and (ii) Groups of females with complete legs or with 1-3 legs lost due to pyrethroid exposure were offered a blood meal and percentages of blood-fed and fully-fed females were recorded. Most females lost a median of 1 leg within 1-48 h post-exposure to deltamethrin. Mortality (after 24 h) was significantly higher for exposed females with lost legs (31.1%), compared to exposed females with complete legs (7.3%), and there were no differences in mortality between females with complete legs and the control (unexposed females). There were no differences between the three treatments in the percentages of blood-fed and fully-fed females. Leg loss in sandflies is a toxic effect of pyrethroids and there was no evidence of autotomy. The loss of up to three legs after exposure to pyrethroids does not affect blood-feeding behaviour in laboratory and probably also in wild conditions.

Phlébotomes de Bolivie: VII. Répartition des deux morphotypes du phlébotome lutzomyia longipalpis (Lutz et Neiva, 1912 (Diptera: Psychodidae dans le piémont andin de Bolivie

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Francois Le Pont

1989-09-01

Full Text Available Deux morphotypes de Lytzomyia longipalpis (Lutz et Neiva, 1912 ont été décrits au Brésil, l'un avec une seule paire de taches tergales, l'autre avec deux paires de taches. Ce caractère est propre aux mâles. En Bolivie, la forme à une tache existe seule dans le foyer de leishmaniose viscérale des Yungas (alt. 1000-2000 m dans l'envirionnement péridomicilliaire; c'est le vecteur confirmé de cette maladie. Le second morphotype à deux taches a été récemment découvert sous le porche de grottes dans le région de Cochabamba (alt. 2700 m; il était absent dans et autour des habitations de cette région, où la leishmaniose vicérale est inconnue. Les deux morphotypes de Lu. longipalpis ont, en Bolivie, une distribution allopatrique, et leurs écologies respectives sont très différentes.

Comparative sensitivity of field and laboratory populations of Hyalella azteca to the pyrethroid insecticides bifenthrin and cypermethrin.

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Clark, Stephen L; Ogle, R Scott; Gantner, Andrew; Hall, Lenwood W; Mitchell, Gary; Giddings, Jeffrey; McCoole, Matthew; Dobbs, Michael; Henry, Kevin; Valenti, Ted

2015-10-01

Hyalella azteca are epibenthic invertebrates that are widely used for toxicity studies. They are reported to be more sensitive to pyrethroid insecticides than most other test species, which has prompted considerable use of this species in toxicity testing of ambient surface waters where the presence of pyrethroids is suspected. However, resident H. azteca have been found in some ambient water bodies reported to contain surface water and/or sediment pyrethroid concentrations that are toxic to laboratory reared H. azteca. This observation suggests differences in the sensitivities of laboratory reared and field populations of H. azteca to pyrethroids. The goal of the present study was to determine the sensitivities of laboratory reared and field populations of H. azteca to the pyrethroids bifenthrin and cypermethrin. Specimens of H. azteca were collected from resident populations at field sites that are subject to varied land-use activities as well as from laboratory populations. These organisms were exposed to bifenthrin- or cypermethrin-spiked water in 96-h water-only toxicity tests. The resulting data demonstrated that: 1) field-collected populations in urban and agricultural settings can be >2 orders of magnitude less sensitive to the pyrethroids than laboratory reared organisms; 2) field-collected organisms varied in their sensitivity (possibly based on land-use activities), with organisms collected from undeveloped sites exhibiting sensitivities similar to laboratory reared organisms; and 3) the sensitivity of field-collected "tolerant" organisms increased in subsequent generations reared under laboratory conditions. Potential mechanisms for these differences are discussed. © 2015 SETAC.

Prevalência da microbiota no trato digestivo de fêmeas de Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera: Psychodidae provenientes do campo

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Oliveira Sandra Maria Pereira de

2000-01-01

Full Text Available No presente trabalho foram dissecados o trato digestivo de 245 fêmeas de Lutzomyia longipalpis originários da Gruta da Lapinha, Município de Lagoa Santa, MG, formando 7 grupos de 35 flebotomíneos. Das 8 espécies de bactérias isoladas houve uma predominância de bactérias Gram negativas (BGN pertencentes ao grupo de não fermentadoras de açúcar das seguintes espécies: Acinetobacter lowffii, Stenotrophomonas maltophhilia, Pseudomonas putida e Flavimonas orizihabitans. No grupo das fermentadoras tivemos: Enterobacter cloacae e Klebsiella ozaenae. No grupo dos Gram positivos foram identificados Bacillus thuringiensis e Staphylococcus spp.

Experimental Population Genetics in the Introductory Genetics Laboratory Using "Drosophila" as a Model Organism

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Johnson, Ronald; Kennon, Tillman

2009-01-01

Hypotheses of population genetics are derived and tested by students in the introductory genetics laboratory classroom as they explore the effects of biotic variables (physical traits of fruit flies) and abiotic variables (island size and distance) on fruit fly populations. In addition to this hypothesis-driven experiment, the development of…

Effects of chlorpyrifos on individuals and populations of Daphnia pulex in the laboratory and field

NARCIS (Netherlands)

Hoeven, N. van der; Gerritsen, A.A.M.

1997-01-01

Effects of the insecticide chlorpyrifos (cpf) on young (laboratory. Populations of D. pulex exposed to cpf were studied in the laboratory and field. In the field, cpf was applied in

Researchin chronic low-level gamma -irradiation on laboratory populations of Lemna minor

International Nuclear Information System (INIS)

Rasskazova, M.M.; Berestina, A.V.

2012-01-01

Researching carried out on the laboratory population of Lemna minor showed that the chronically γ-irradiated plants significantly reduced specific rate of population growth, accelerating the process of withering away of the fronds. Chronic irradiation with dose of 5,0 mGy/h stimulates the growth of the roots, and irradiation with a capacity of 50 mGy/h significantly increases the percentage of damage fronds. Found out independent of dose effect on the criterion of the number of deaths of individuals in the range of absorbed dose between 0,01 - 1 Gy. (authors)

Challenging the Wigglesworthia, Sodalis, Wolbachia symbiosis dogma in tsetse flies: Spiroplasma is present in both laboratory and natural populations.

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Doudoumis, V; Blow, F; Saridaki, A; Augustinos, A; Dyer, N A; Goodhead, I; Solano, P; Rayaisse, J-B; Takac, P; Mekonnen, S; Parker, A G; Abd-Alla, A M M; Darby, A; Bourtzis, K; Tsiamis, G

2017-07-05

Profiling of wild and laboratory tsetse populations using 16S rRNA gene amplicon sequencing allowed us to examine whether the "Wigglesworthia-Sodalis-Wolbachia dogma" operates across species and populations. The most abundant taxa, in wild and laboratory populations, were Wigglesworthia (the primary endosymbiont), Sodalis and Wolbachia as previously characterized. The species richness of the microbiota was greater in wild than laboratory populations. Spiroplasma was identified as a new symbiont exclusively in Glossina fuscipes fuscipes and G. tachinoides, members of the palpalis sub-group, and the infection prevalence in several laboratory and natural populations was surveyed. Multi locus sequencing typing (MLST) analysis identified two strains of tsetse-associated Spiroplasma, present in G. f. fuscipes and G. tachinoides. Spiroplasma density in G. f. fuscipes larva guts was significantly higher than in guts from teneral and 15-day old male and female adults. In gonads of teneral and 15-day old insects, Spiroplasma density was higher in testes than ovaries, and was significantly higher density in live versus prematurely deceased females indicating a potentially mutualistic association. Higher Spiroplasma density in testes than in ovaries was also detected by fluorescent in situ hybridization in G. f. fuscipes.

Genetic variation in laboratory and field populations of the vector of bluetongue virus, Culicoides variipennis (Diptera: Ceratopogonidae).

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Tabachnick, W J

1990-01-01

Laboratory colonies and several natural populations of the biting midge Culicoides variipennis (Coquillett) were analyzed for genetic variation at 21 electrophoretic loci. The laboratory colonies maintained high levels of genetic variation measured by average expected heterozygosities (He = 0.142 +/- 0.008), although levels were lower than those observed in field collections (He = 0.198 +/- 0.009). A field population from Colorado, analyzed five times over a 1-yr period, showed a consistent trend in the change in gene frequencies at two loci. Genetic comparisons between natural populations were consistent with the existence of two subspecies. C. variipennis variipennis and C. variipennis sonorensis Wirth & Jones.

Fonte alimentar sangüínea e a peridomiciliação de Lutzomyia longipalpis (Lutz & Neiva, 1912 (Psychodidae, Phlebotominae Blood feeding sources and peridomiciliation of Lutzomyia longipalpis (Lutz & Neiva, 1912 (Psychodidae, Phlebotominae

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Flávio de Oliveira Passos Dias

2003-10-01

Full Text Available Estudou-se por meio da reação da precipitina, o conteúdo estomacal de Lutzomyia longipalpis nos ambientes intradomiciliar e peridoméstico, no Município de Raposa, Maranhão, área de transmissão de leishmaniose visceral ou "calazar". De 2.240 fêmeas capturadas, 547 (24,4% estavam alimentadas com sangue de vertebrados nas proporções que seguem: ave (87,9%; roedor (47,2%; humano (42,4%, cão (27,6%; mucura (26,6% e eqüino (22,5%. A investigação levada a efeito em 120 habitações confirmou a galinha como o animal doméstico mais comum no ambiente peridoméstico (28,3%, seguido pelo cão (21,7%, gato (17,5%, jumento (13,3%, pombo (7,5%, coelho (3,3% e pato (3,3%; enquanto o cavalo, marreco e porco representaram, cada um, 1,7%. Entre os animais sinantrópicos, a mucura foi a mais citada naquele ambiente (39,3%, seguida pelo rato (37,9%, morcego (14,3% guaxinim (3,6%, raposa (2,1%, cobra (1,4% e sapo (1,4%. A presença no peridomicílio de animais domésticos e sinantrópicos e o encontro de flebótomos alimentados, ao mesmo tempo, com sangue humano, de mucura e de canídeos, corroboram a hipótese de que a transmissão do calazar esteja ocorrendo realmente no ambiente antrópico, no Município de Raposa.A precipitin test was employed to study the alimentary tract content of Lutzomyia longipalpis in the intra- and peridomiciliary environments in the municipality of Raposa, Maranhão State, a transmission area for visceral leishmaniasis or kala azar. Out of 2,240 female sandflies captured, 547 (24.4% had fed on vertebrate blood, with the following proportions: avian (87.9%; rodent (47.2%; human (42.4%; canine (27.6%; opossum (26.6%; and equine (22.5%. Based on a survey of 120 human dwellings, chickens were found to be the most common domestic animals in the peridomicile (28.3%, followed by dogs (21.7%, cats (17.5%, donkeys (13.3%, pigeons (7.5%, rabbits (3.3%, ducks (3.3%, and horses, mallards, and pigs (1.7% each. Synanthropic animals

Development and population growth of Hydra viridissima Pallas, 1766 (Cnidaria, Hydrozoa in the laboratory

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FC. Massaro

Full Text Available Hydras, the most representative freshwater Cnidaria, are of common occurrence in bodies of water in every continent except Antarctica. This study was planned with the aim of maintaining a population of Hydra viridissima in laboratory culture to enable the determination of the individual and population growth-rates of this species, as well as its population doubling time and generation time, with a view to employing these common animals as test-organisms in ecotoxicological assays. The organisms were maintained in reconstituted water at 20 ± 2 °C, illuminated at 800 lux with a photoperiod of 12 hours light: 12 hours dark, and were fed on neonates of the cladoceran Ceriodaphnia silvestrii (3 or 4 neonates per hydra, 3 times a week. The individual growth-rate (k of the species was 0.43, the maximum length of the column 2.53 mm and the generation time 6.6 ± 1.5 days on average. The hydra population showed an intrinsic growth-rate (r of 0.0468, according to the fitted curve, and a doubling time of 14.8 ± 2.63 days. Hydra viridissima is easy to grow in the laboratory and performs well in the conditions used in this study. It is thus a promising candidate test-organism for ecotoxicological studies.

Population array and agricultural data arrays for the Los Alamos National Laboratory

International Nuclear Information System (INIS)

Jacobson, K.W.; Duffy, S.; Kowalewsky, K.

1998-07-01

To quantify or estimate the environmental and radiological impacts from man-made sources of radioactive effluents, certain dose assessment procedures were developed by various government and regulatory agencies. Some of these procedures encourage the use of computer simulations (models) to calculate air dispersion, environmental transport, and subsequent human exposure to radioactivity. Such assessment procedures are frequently used to demonstrate compliance with Department of Energy (DOE) and US Environmental Protection Agency (USEPA) regulations. Knowledge of the density and distribution of the population surrounding a source is an essential component in assessing the impacts from radioactive effluents. Also, as an aid to calculating the dose to a given population, agricultural data relevant to the dose assessment procedure (or computer model) are often required. This report provides such population and agricultural data for the area surrounding Los Alamos National Laboratory

Using ecology to inform physiology studies: implications of high population density in the laboratory.

Science.gov (United States)

Newman, Amy E M; Edmunds, Nicholas B; Ferraro, Shannon; Heffell, Quentin; Merritt, Gillian M; Pakkala, Jesse J; Schilling, Cory R; Schorno, Sarah

2015-03-15

Conspecific density is widely recognized as an important ecological factor across the animal kingdom; however, the physiological impacts are less thoroughly described. In fact, population density is rarely mentioned as a factor in physiological studies on captive animals and, when it is infrequently addressed, the animals used are reared and housed at densities far above those in nature, making the translation of results from the laboratory to natural systems difficult. We survey the literature to highlight this important ecophysiological gap and bring attention to the possibility that conspecific density prior to experimentation may be a critical factor influencing results. Across three taxa: mammals, birds, and fish, we present evidence from ecology that density influences glucocorticoid levels, immune function, and body condition with the intention of stimulating discussion and increasing consideration of population density in physiology studies. We conclude with several directives to improve the applicability of insights gained in the laboratory to organisms in the natural environment. Copyright © 2015 the American Physiological Society.

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).

Science.gov (United States)

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.

Comparison of laboratory single species and field population-level effects of the pyrethroid insecticide lambda-cyhalothrin on freshwater invertebrates

NARCIS (Netherlands)

Schroer, A.F.W.; Belgers, J.D.M.; Brock, T.C.M.; Matser, A.M.; Maund, S.J.; Brink, van den P.J.

2004-01-01

The toxicity of the pyrethroid insecticide lambda-cyhalothrin to freshwater invertebrates has been investigated using data from short-term laboratory toxicity tests and in situ bioassays and population-level effects in field microcosms. In laboratory tests, patterns of toxicity were consistent with

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.

Science.gov (United States)

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.

Laboratory database population surveillance to improve detection of progressive chronic kidney disease.

Science.gov (United States)

Kennedy, David M; Chatha, Kamaljit; Rayner, Hugh C

2013-09-01

Some patients with chronic kidney disease are still referred late for specialist care despite the evidence that earlier detection and intervention can halt or delay progression to end-stage kidney disease (ESKD). To develop a population surveillance system using existing laboratory data to enable early detection of patients at high risk of ESKD by reviewing cumulative graphs of estimated glomerular filtration rate (eGFR). A database was developed, updated daily with data from the laboratory computer. Cumulative eGFR graphs containing up to five years of data are reviewed by clinical scientists for all primary care patients or out-patients with a low eGFR for their age. For those with a declining trend, a report containing the eGFR graph is sent to the requesting doctor. A retrospective audit was performed using historical data to assess the predictive value of the graphs. In nine months, we reported 370,000 eGFR results, reviewing 12,000 eGFR graphs. On average 60 graphs per week were flagged as 'high' or 'intermediate' risk. Patients with graphs flagged as high risk had a significantly higher mortality after 3.5 years and a significantly greater chance of requiring renal replacement therapy after 4.5 years of follow-up. Five patients (7%) with graphs flagged as high risk had a sustained >25% fall in eGFR without evidence of secondary care referral. Feedback about the service from requesting clinicians was 73% positive. We have developed a system for laboratory staff to review cumulative eGFR graphs for a large population and identify patients at highest risk of developing ESKD. Further research is needed to measure the impact of this service on patient outcomes. © 2013 European Dialysis and Transplant Nurses Association/European Renal Care Association.

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

Science.gov (United States)

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.

Can we use laboratory reared copepods for experiments - a comparison of feeding behavior and reproduction between a field and a laboratory population of Acartia tonsa

DEFF Research Database (Denmark)

Tiselius, P.; Hansen, B.; Jonsson, P.

1995-01-01

Motility patterns and egg production were investigated in two populations of Acartia tonsa, field animals from the Oresund and laboratory animals from a 12-year-old (approximate to 120 generations) culture. When observed in aquaria with a layer of Thalassiosira weissflogii in the middle, laboratory...... differed considerably from held-caught A. tonsa from the eastern United States, where both behaviour and egg production changed consistently and in accordance with a strong aggregation in food patches. (C) 1995 International Council for the Exploration of the Sea...

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

Male convict cichlid 11-ketotestosterone levels throughout the reproductive cycle: an exploratory profile study in laboratory and field populations

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Natalie April van Breukelen

2015-05-01

Full Text Available The convict cichlid (Amatitlania nigrofasciata has been extensively examined in relation to many behavioral topics, such as courtship, pair-bonding, bi-parental care, and territoriality. Recently, this model species has been utilized in studies on genetics, endocrinology, and neuroanatomy, with an ultimate goal of connecting behavior with its underlying mechanisms. The goal of this study was two-fold: (1 profile the circulating levels of plasma 11KT in the male convict cichlid at multiple points during the reproductive cycle and (2 generally compare the hormonal profiles of the widely used laboratory populations and those of a free-living population in the streams of Costa Rica. The results of the field experiment showed that male convict cichlids had higher levels of circulating 11KT during courtship and lower during the parental care and non-breeding phases. The profile of the laboratory population was similar to the profile of the free-living individuals, with significantly higher levels of 11KT occurring during courtship than during parental care, though the level of 11KT during non-breeding phase was elevated in the laboratory. The high levels of 11KT during courtship and low levels of 11KT during parental care found in both the field and the laboratory is similar to what has been reported in other species of teleosts, and may suggest an important function of 11KT in the expression of courtship behavior and the subsequent onset of parental behaviors in this model species.

Identificação do sangue ingerido por Lutzomyia (Lutzomyia) longipalpis (Lutz & Neiva, 1912) e Lutzomyia (Lutzomyia) almerioi (Galati & Nunes, 1999) pela técnica imunoenzimática do ELISA de captura, no sistema avidina-biotina

OpenAIRE

Marassá,Ana Maria; Consales,Cleide Aschenbrenner; Galati,Eunice Aparecida Bianchi; Nunes,Vânia Lúcia Brandão

2006-01-01

Lutzomyia longipalpis e Lutzomyia almerioi, espécies integrantes da fauna flebotomínea da Serra da Bodoquena, no Estado de Mato Grosso do Sul, têm sido objeto de estudo devido às suas elevadas abundâncias no Assentamento Guaicurus, foco de leishmaniose tegumentar humana e visceral canina. Em pesquisas que vem sendo realizadas neste acampamento para a identificação de vetores destas parasitoses, foram capturados no período de 2002 a 2004, com armadilhas automáticas luminosas, instaladas em amb...

Comparison of laboratory single species and field population-level effects of the pyrethroid insecticide lambda-cyhalothrin on freshwater invertebrates.

Science.gov (United States)

Schroer, A F W; Belgers, J D M; Brock, T C M; Matser, A M; Maund, S J; Van den Brink, P J

2004-04-01

The toxicity of the pyrethroid insecticide lambda-cyhalothrin to freshwater invertebrates has been investigated using data from short-term laboratory toxicity tests and in situ bioassays and population-level effects in field microcosms. In laboratory tests, patterns of toxicity were consistent with previous data on pyrethroids. The midge Chaoborus obscuripes was most sensitive (48- and 96-h EC50 = 2.8 ng/L). Other insect larvae (Hemiptera, Ephemeroptera) and macrocrustacea (Amphipoda, Isopoda) were also relatively sensitive, with 48- and 96-h EC50 values between 10 and 100 ng/L. Generally, microcrustacea (Cladocera, Copepoda) and larvae of certain insect groups (Odonata and Chironomidae) were less sensitive, with 48-h EC50 values higher than 100 ng/L. Mollusca and Plathelminthes were insensitive and were unaffected at concentrations at and above the water solubility (5 microg/L). Generally, the EC50 values based on initial population responses in field enclosures were similar to values derived from laboratory tests with the same taxa. Also, the corresponding fifth and tenth percentile hazard concentrations (HC5 and HC10) were similar (laboratory HC5 = 2.7 ng/L and field HC5 = 4.1 ng/L; laboratory and field HC10 = 5.1 ng/L), at least when based on the same sensitive taxonomic groups (insects and crustaceans) and when a similar concentration range was taken into account. In the three field enclosure experiments and at a treatment level of 10 ng/L, consistent effects were observed for only one population (Chaoborus obscuripes), with recovery taking place within 3 to 6 weeks. The laboratory HC5 (2.7 ng/L) and HC10 (5.1 ng/L) based on acute EC50 values of all aquatic arthropod taxa were both lower than this 10 ng/L, a concentration that might represent the "regulatory acceptable concentration." The HC5 and HC10 values in this study in The Netherlands (based on static laboratory tests with freshwater arthropods) were very similar to those derived from a previous study in

Some effects of temperature and starvation on the bivalve @iDonax vittatus@@ (da Costa) in experimental laboratory populations

Digital Repository Service at National Institute of Oceanography (India)

Ansell, A.D.; Sivadas, P.

The effect of temperature on the body weight and composition, and on respiration, filtration and NH, excretion of the bivalve Donax uittatus (da Costa) has been investigated in laboratory-maintained populations under conditions of starvation In all...

Diseases and parasites of laboratory reared and wild population of banded pearl spot Etroplus suratensis (Cichlidae) in Goa

Digital Repository Service at National Institute of Oceanography (India)

Rattan, P.; Parulekar, A.H.

Banded Pearl spot Etroplus suratensis, the inhabitant of coastal backwaters and lagoons is one among the few finfish species identified for brackishwater farming. Common diseases and parasites from the wild population of Goa and from the laboratory...

A comparison of results from two mycology laboratories for the diagnosis of onychomycosis: a study of 85 cases in a geriatric population.

Science.gov (United States)

Scherer, William P; Scherer, Michael D

2004-01-01

An investigative study was performed to compare the results from two mycology laboratories for the diagnosis of onychomycosis in a geriatric population and to determine the possible pharmacologic treatments based on the two laboratories' results. In this study, 85 cases of suspected onychomycosis involving men and women 65 years and older from a nursing home setting in South Florida were used. Samples were taken from the hallux toenail and sent to two different mycology laboratories for fluorescent potassium hydroxide preparation and microscopic examination of a fungal culture. Of the 85 cases studied, the two mycology laboratories reported similar potassium hydroxide preparation results for 58.8% of the patients and similar fungal culture results for genus and species identification for 37.6% of the patients. When the potassium hydroxide preparation and fungal culture results were combined, the two mycology laboratories reported similar results for only 27.1% of the patients. As a result of the two mycology laboratories' findings, the possible US Food and Drug Administration-approved pharmacologic treatments may differ for 43.5% of the patients studied. The discrepancy between the two independent laboratories leaves physicians to question the reproducibility of fluorescent potassium hydroxide preparation and fungal culture analysis in a geriatric patient population for the diagnosis of onychomycosis.

Induction and transmission of tolerance to the synthetic pesticide emamectin benzoate in field and laboratory populations of diamondback moth.

Science.gov (United States)

Rahman, M M; Baker, G; Powis, K J; Roush, R T; Schmidt, O

2010-08-01

Field surveys of pest insect pest populations in agroecosystems reveal low but significant levels of tolerance to synthetic and biological pesticides but fail to uncover resistance alleles in test crosses. To study the potential of inducible mechanisms to generate tolerance to synthetic pesticides, we performed baseline susceptibility studies in field and laboratory populations of diamondback moth, Plutella xylostella (L.), to commercial formulations of emamectin benzoate. Pesticide exposure in the field caused elevated levels of tolerance, which decreased in field-collected populations after maintaining insects with pesticide-free diet in the laboratory. Because no significant resistance alleles were identified in back-crossed individuals, the observed increase in tolerance was probably not based on preexisting recessive resistance mechanisms in the population. Instead, the genetic analysis after five and 12 generations is compatible with a transient up-regulation of an immune and metabolic status in tolerant insects that can be transmitted to offspring by a maternal effect. Although the epigenetic effects contributed to incremental increases in tolerance in the first five generations, other resistance mechanisms that are transmitted genetically predominate after 12 generations of increased exposure to the pesticide.

Mutational meltdown in laboratory yeast populations

NARCIS (Netherlands)

Zeyl, C.; Mizesko, M.; Visser, de J.A.G.M.

2001-01-01

In small or repeatedly bottlenecked populations, mutations are expected to accumulate by genetic drift, causing fitness declines. In mutational meltdown models, such fitness declines further reduce population size, thus accelerating additional mutation accumulation and leading to extinction. Because

Leishmania infection and blood food sources of phlebotomines in an area of Brazil endemic for visceral and tegumentary leishmaniasis

Science.gov (United States)

Guimarães-e-Silva, Antônia Suely; Silva, Soraia de Oliveira; Ribeiro da Silva, Rosa Cristina; Pinheiro, Valéria Cristina Soares; Rebêlo, José Manuel Macário; Melo, Maria Norma

2017-01-01

The aims of the study were to determine the blood feeding preferences of sandflies and to identify species of Leishmania that infected phlebotomines in Caxias, Maranhão, Brazil, an area that is highly endemic for leishmaniasis. Sandflies were captured in light traps located in the peridomiciliary environments of randomly selected houses in urban and rural settings between 1800 and 0600 hours on new moon days between March 2013 and February 2015. DNA extracts from 982 engorged female sandflies were submitted to fragment length polymorphism analysis to identify infecting species of Leishmania, and blood sources were identified for 778 of these specimens. Infection by Leishmania infantum was detected in Lutzomyia longipalpis, Lu. whitmani and Lu. termitophila; L. infantum/L. braziliensis in Lu. longipalpis, Lu. whitmani and Lu. trinidadensis; L. shawi in Lu. longipalpis; L. mexicana in Lu. longipalpis; L. braziliensis in Lu. longipalpis and Lu. whitmani; L. guyanensis in Lu. longipalpis and Lu. termitophila; L. amazonensis in Lu. longipalpis and L. lainsoni or L. naiffi in Lu. longipalpis, while Lu. longipalpis and Lu. trinidadensis were infected with unidentified Leishmania sp. Blood sources were identified in 573 individual phlebotomines and the preferred hosts were, in decreasing order, chicken, dog, rodent and human with lower preferences for pig, horse, opossum and cattle. Lu. longipalpis and Lu. whitmani performed mixed feeding on man, dog and rodent, while Lu. longipalpis was the most opportunistic species, feeding on the blood of all hosts surveyed, but preferably on dog/chicken, dog/rodent and rodent/chicken. Our findings reveal the concomitant circulation of Leishmania species that cause visceral leishmaniasis and tegumentary leishmaniasis in the study area, and explain the occurrence of autochthonous human cases of both clinical forms of leishmaniasis in Caxias, Maranhão. The results support our hypothesis that, in the municipality of Caxias, transmission

Experimental infection of Leishmania (L. chagasi in a cell line derived from Lutzomyia longipalpis (Diptera:Psychodidae

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Felio J Bello

2005-10-01

Full Text Available The present work describes the in vitro infection of a cell line Lulo, derived from Lutzomyia longipalpis embryonic tissue, by Leishmania chagasi promastigotes. This infection process is compared with a parallel one developed using the J774 cell line. The L. chagasi MH/CO/84/CI-044B strain was used for experimental infection in two cell lines. The cells were seeded on glass coverslips in 24-well plates to reach a final number of 2 x 10(5 cells/well. Parasites were added to the adhered Lulo and J774 cells in a 10:1 ratio and were incubated at 28 and 37ºC respectively. After 2, 4, 6, 8, and 10 days post-infection, the cells were extensively washed with PBS, fixed with methanol, and stained with Giemsa. The number of internalized parasites was determined by counting at least 400 cultured cells on each coverslip. The results showed continuous interaction between L. chagasi promastigotes with the cell lines. Some ultrastructural characteristics of the amastigote forms were observed using transmission electron microscopy. The highest percentage of infection in Lulo cells was registered on day 6 post-infection (29.6% and on day 4 in the J774 cells (51%. This work shows similarities and differences in the L. chagasi experimental infection process in the two cell lines. However, Lulo cells emerge as a new model to study the life-cycle of this parasite.

Use of HOMA-IR to diagnose non-alcoholic fatty liver disease: a population-based and inter-laboratory study.

Science.gov (United States)

Isokuortti, Elina; Zhou, You; Peltonen, Markku; Bugianesi, Elisabetta; Clement, Karine; Bonnefont-Rousselot, Dominique; Lacorte, Jean-Marc; Gastaldelli, Amalia; Schuppan, Detlef; Schattenberg, Jörn M; Hakkarainen, Antti; Lundbom, Nina; Jousilahti, Pekka; Männistö, Satu; Keinänen-Kiukaanniemi, Sirkka; Saltevo, Juha; Anstee, Quentin M; Yki-Järvinen, Hannele

2017-10-01

Recent European guidelines for non-alcoholic fatty liver disease (NAFLD) call for reference values for HOMA-IR. In this study, we aimed to determine: (1) the upper limit of normal HOMA-IR in two population-based cohorts; (2) the HOMA-IR corresponding to NAFLD; (3) the effect of sex and PNPLA3 genotype at rs738409 on HOMA-IR; and (4) inter-laboratory variations in HOMA-IR. We identified healthy individuals in two population-based cohorts (FINRISK 2007 [n = 5024] and the Programme for Prevention of Type 2 Diabetes in Finland [FIN-D2D; n = 2849]) to define the upper 95th percentile of HOMA-IR. Non-obese individuals with normal fasting glucose levels, no excessive alcohol use, no known diseases and no use of any drugs were considered healthy. The optimal HOMA-IR cut-off for NAFLD (liver fat ≥5.56%, based on the Dallas Heart Study) was determined in 368 non-diabetic individuals (35% with NAFLD), whose liver fat was measured using proton magnetic resonance spectroscopy ( 1 H-MRS). Samples from ten individuals were simultaneously analysed for HOMA-IR in seven European laboratories. The upper 95th percentiles of HOMA-IR were 1.9 and 2.0 in healthy individuals in the FINRISK (n = 1167) and FIN-D2D (n = 459) cohorts. Sex or PNPLA3 genotype did not influence these values. The optimal HOMA-IR cut-off for NAFLD was 1.9 (sensitivity 87%, specificity 79%). A HOMA-IR of 2.0 corresponded to normal liver fat (HOMA-IR measured in Helsinki corresponded to 1.3, 1.6, 1.8, 1.8, 2.0 and 2.1 in six other laboratories. The inter-laboratory CV% of HOMA-IR was 25% due to inter-assay variation in insulin (25%) rather than glucose (5%) measurements. The upper limit of HOMA-IR in population-based cohorts closely corresponds to that of normal liver fat. Standardisation of insulin assays would be the first step towards definition of normal values for HOMA-IR.

Changing trends of hepatitis b seromarkers amongst pakistani population: a laboratory-based review

International Nuclear Information System (INIS)

Zafar, A.; Khan, E.; Khan, M.S.; Moiz, B.; Jafri, W.

2013-01-01

Objective: To study the changing trends of hepatitis B markers tested at Aga Khan University Hospital clinical laboratory according to the internationally recognised classification of hepatitis B profile. Methods: The retrospective study involved analysis of laboratory records of hepatitis B profiles of all patients collected from January 2001 to December 2008 at the Aga Khan University Hospital's clinical laboratory. Patients with complete profile tested were categorised according to the Centre for Diseases Control classification of hepatitis B profile. SPSS 16 was used for statistical analysis. Results: A total of 185,825 patients had serological markers for hepatitis B tested. Mean-age of reactive hepatitis B surface antigen (HBsAg) patients was 30+-12.5 years. HBsAg reactivity was significantly higher in males than females (34% vs 12%; p <0.0001). HBsAg showed a slight decline in the percentage reactivity during the 8-year study period, while a gradual increase in hepatitis B surface antibody (HBsAb) reactivity was observed. Of the total, 23% patients belonged to the 'susceptible to infection' category; 39% patients were classified as 'chronically-ill'; 12% patients were categorised as 'immune due to hepatitis B vaccination'. 3% patients were classed as 'acutely infected'. Overall, samples received from Peshawar, Quetta and Larkana showed very high reactivity rates. Conclusion: The study substantiated the general perception that levels of HBsAg is showing a decreasing trend, while levels of HBsAb are increasing perhaps due to better vaccination of population. (author)

Use of HOMA-IR to diagnose non-alcoholic fatty liver disease: a population-based and inter-laboratory study

OpenAIRE

Isokuortti, Elina; Zhou, You; Peltonen, Markku; Bugianesi, Elisabetta; Clement, Karine; Bonnefont-Rousselot, Dominique; Lacorte, Jean-Marc; Gastaldelli, Amalia; Schuppan, Detlef; Schattenberg, Jörn M.; Hakkarainen, Antti; Lundbom, Nina; Jousilahti, Pekka; Männistö, Satu; Keinänen-Kiukaanniemi, Sirkka

2017-01-01

Aims/hypothesis\\ud \\ud Recent European guidelines for non-alcoholic fatty liver disease (NAFLD) call for reference values for HOMA-IR. In this study, we aimed to determine: (1) the upper limit of normal HOMA-IR in two population-based cohorts; (2) the HOMA-IR corresponding to NAFLD; (3) the effect of sex and PNPLA3 genotype at rs738409 on HOMA-IR; and (4) inter-laboratory variations in HOMA-IR.\\ud \\ud Methods\\ud \\ud We identified healthy individuals in two population-based cohorts (FINRISK 20...

Environmental surveillance program of the Lawrence Berkeley Laboratory

International Nuclear Information System (INIS)

Thomas, R.H.

1976-04-01

The major radiological environmental impact of the Lawrence Berkeley Laboratory is due to the operation of four particle accelerators. Potential sources of population exposure at the Laboratory are discussed. The major source of population exposure due to accelerator operation arises from the prompt radiation field which consists principally of neutrons and photons. Release of small quantities of radionuclides is also a potential source of population exposure but is usually an order of magnitude less significant. Accelerator produced radiation levels at the Laboratory boundary are comparable with the magnitudes of the fluctuations found in the natural background radiation. Environmental monitoring of accelerator-produced radiation and of radionuclides is carried on throughout the Laboratory, at the Laboratory perimeter, and in the regions surrounding the Laboratory. The techniques used are described. The models used to calculate population exposure are described and discussed

Evaluation of chemical spraying and environmental management efficacy in areas with minor previous application of integrated control actions for visceral leishmaniasis in Brazil.

Science.gov (United States)

Lara-Silva, Fabiana de Oliveira; Michalsky, Érika Monteiro; Fortes-Dias, Consuelo Latorre; Fiuza, Vanessa de Oliveira Pires; Dias, Edelberto Santos

2017-12-01

Leishmaniases are vector-borne diseases that are transmitted to humans through the bite of Leishmania-infected phlebotomine sand flies (Diptera:Psychodidae). The main proved vector of visceral leishmaniais (VL) in the New World - Lutzomyia longipalpis - is well-adapted to urban areas and has extensive distribution within the five geographical regions of Brazil. Integrated public health actions directed for the vector, domestic reservoir and humans for the control of VL are preferentially applied in municipalities with higher epidemiological risk of transmission. In this study, we evaluated the individual impact of two main vector control actions - chemical spraying and environmental management - in two districts with no reported cases of human VL. Although belonging to an endemic municipality for VL in Brazil, the integrated control actions have not been applied in these districts due to the absence of human cases. The number of L. longipalpis captured in a two-year period was used as indicator of the population density of the vector. After chemical spraying a tendency of reduction in L. longipalpis was observed but with no statistical significance compared to the control. Environmental management was effective in that reduction and it may help in the control of VL by reducing the population density of the vector in a preventive and more permanent action, perhaps associated with chemical spraying. Copyright © 2017 Elsevier B.V. All rights reserved.

The role of gallery forests in maintaining Phlebotominae populations: potential Leishmania spp. vectors in the Brazilian savanna

Directory of Open Access Journals (Sweden)

Tâmara Dias Oliveira Machado

Full Text Available BACKGROUND Knowledge on synanthropic phlebotomines and their natural infection by Leishmania is necessary for the identification of potential areas for leishmaniasis occurrence. OBJECTIVE To analyse the occurrence of Phlebotominae in gallery forests and household units (HUs in the city of Palmas and to determine the rate of natural infection by trypanosomatids. METHODS Gallery forests and adjacent household areas were sampled on July (dry season and November (rainy season in 2014. The total sampling effort was 960 HP light traps and eight Shannon traps. Trypanosomatids were detected in Phlebotominae females through the amplification of the SSU rDNA region, and the positive samples were used in ITS1-PCR. Trypanosomatid species were identified using sequencing. FINDINGS A total of 1,527 sand flies representing 30 species were captured in which 949 (28 spp. and 578 (22 spp. were registered in July and November, respectively. In July, more specimens were captured in the gallery forests than in the HUs, and Nyssomyia whitmani was particularly frequent. In November, most of the specimens were found in the HUs, and again, Ny. whitmani was the predominant species. Lutzomyia longipalpis was commonly found in domestic areas, while Bichromomyia flaviscutellata was most frequent in gallery forests. Molecular analysis of 154 pools of females (752 specimens identified Leishmania amazonensis, L. infantum, and Crithidia fasciculata in Ny. whitmani, as well as L. amazonensis in Lu. longipalpis, Trypanosoma sp. and L. amazonensis in Pintomyia christenseni, and L. amazonensis in both Psathyromyia hermanlenti and Evandromyia walkeri. MAIN CONCLUSIONS These results show the importance of gallery forests in maintaining Phlebotominae populations in the dry month, as well as their frequent occurrence in household units in the rainy month. This is the first study to identify Leishmania, Trypanosoma, and Crithidia species in Phlebotominae collected in Palmas, Tocantins

The role of gallery forests in maintaining Phlebotominae populations: potential Leishmania spp. vectors in the Brazilian savanna.

Science.gov (United States)

Machado, Tâmara Dias Oliveira; Minuzzi-Souza, Thaís Tâmara Castro; Ferreira, Tauana de Sousa; Freire, Luciana Pereira; Timbó, Renata Velôzo; Vital, Tamires Emanuele; Nitz, Nadjar; Silva, Mariana Neiva; Santos, Alcinei de Souza; Sales, Nathyla Morgana Cunha; Obara, Marcos Takashi; Andrade, Andrey José de; Gurgel-Gonçalves, Rodrigo

2017-10-01

Knowledge on synanthropic phlebotomines and their natural infection by Leishmania is necessary for the identification of potential areas for leishmaniasis occurrence. To analyse the occurrence of Phlebotominae in gallery forests and household units (HUs) in the city of Palmas and to determine the rate of natural infection by trypanosomatids. Gallery forests and adjacent household areas were sampled on July (dry season) and November (rainy season) in 2014. The total sampling effort was 960 HP light traps and eight Shannon traps. Trypanosomatids were detected in Phlebotominae females through the amplification of the SSU rDNA region, and the positive samples were used in ITS1-PCR. Trypanosomatid species were identified using sequencing. A total of 1,527 sand flies representing 30 species were captured in which 949 (28 spp.) and 578 (22 spp.) were registered in July and November, respectively. In July, more specimens were captured in the gallery forests than in the HUs, and Nyssomyia whitmani was particularly frequent. In November, most of the specimens were found in the HUs, and again, Ny. whitmani was the predominant species. Lutzomyia longipalpis was commonly found in domestic areas, while Bichromomyia flaviscutellata was most frequent in gallery forests. Molecular analysis of 154 pools of females (752 specimens) identified Leishmania amazonensis, L. infantum, and Crithidia fasciculata in Ny. whitmani, as well as L. amazonensis in Lu. longipalpis, Trypanosoma sp. and L. amazonensis in Pintomyia christenseni, and L. amazonensis in both Psathyromyia hermanlenti and Evandromyia walkeri. These results show the importance of gallery forests in maintaining Phlebotominae populations in the dry month, as well as their frequent occurrence in household units in the rainy month. This is the first study to identify Leishmania, Trypanosoma, and Crithidia species in Phlebotominae collected in Palmas, Tocantins, Brazil.

Irritability Levels of Field and Laboratory Population of Culex pipiens Complex in Tehran to Different Groups of Insecticides

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Sara Rahimi

2016-01-01

Full Text Available Background: The irritant effect of some insecticides can cause a proportion of mosquitoes to leave the sprayed rooms before acquiring a lethal dose, so the repeated contact al sub-lethal dose may lead to extent the resistance.Methods: Larvae and pupae of Culex pipiens complex were collected in mass from open canals of waste water in capital city Tehran and reared to obtain the first generation at laboratory. Sugar-fed 2–3 days female mosquitoes were used for the experiments and compared with laboratory strain. The irritability tests of insecticides impregnated pa­pers were measured in plastic conical exposure chambers placed which implemented at controlled conditions ac­cording  to  the  method  described  by WHO .Number of take-offs were counted during 15  minutes of exposure  time.Results: DDT had the most irritancy effect against field population of Cx. pipiens. DDT, permethrin and deltamethrin was moderately irritable against laboratory strain, whereas, addition to three previous insecticides, malathion, cyfluthrin and propoxur should be also considered as moderately irritable insecticides for field population of. Irritability level of etofenprox, fenithrothion, bendiocarb, and lambdacyhalothrin did not differ from control group.Conclusion: The irritability response of mosquitoes may have a negative impact on control measures. Periodical execution of irritability tests with insecticides that routinely used in vector control program is highly recommended.

The effects of the fungus Metarhizium anisopliae var. acridum on different stages of Lutzomyia longipalpis (Diptera: Psychodidae).

Science.gov (United States)

Amóra, Sthenia Santos Albano; Bevilaqua, Claudia Maria Leal; Feijó, Francisco Marlon Carneiro; Pereira, Romeika Hermínia de Macedo Assunção; Alves, Nilza Dutra; Freire, Fúlvio Aurélio de Morais; Kamimura, Michel Toth; de Oliveira, Diana Magalhães; Luna-Alves Lima, Elza Aurea; Rocha, Marcos Fábio Gadelha

2010-03-01

The control of Visceral Leishmaniasis (VL) vector is often based on the application of chemical residual insecticide. However, this strategy has not been effective. The continuing search for an appropriate vector control may include the use of biological control. This study evaluates the effects of the fungus Metarhizium anisopliae var. acridum on Lutzomyia longipalpis. Five concentrations of the fungus were utilized, 1 x 10(4) to 1 x 10(8) conidia/ml, accompanied by controls. The unhatched eggs, larvae and dead adults previously exposed to fungi were sown to reisolate the fungi and analysis of parameters of growth. The fungus was subsequently identified by PCR and DNA sequencing. M. anisopliae var. acridum reduced egg hatching by 40%. The mortality of infected larvae was significant. The longevity of infected adults was lower than that of negative controls. The effects of fungal infection on the hatching of eggs laid by infected females were also significant. With respect to fungal growth parameters post-infection, only vegetative growth was not significantly higher than that of the fungi before infection. The revalidation of the identification of the reisolated fungus was confirmed post-passage only from adult insects. In terms of larvae mortality and the fecundity of infected females, the results were significant, proving that the main vector species of VL is susceptible to infection by this entomopathogenic fungus in the adult stage. Copyright 2009 Elsevier B.V. All rights reserved.

Benefits of the New Laboratory Methods of the Vigilance of the Health of Cienfuegos Population

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Pedro Sánchez Frenes

2015-03-01

Full Text Available The vigilance of laboratory is the one that is developed on the general population or selected groups by means of the use of tests stop to sieve some health problems. As a part of sanitary strategies of the country, the technologies of the Ultrmicroanalytic System with the aim of strengthen the vigilance of infectious, tumor, congenital disease, among others. Its diagnostic capability has been enlarged and diversified, granting to the work of this system, a new conception, constituting a fortress of the health system in each municipality.

Lower galactosylation levels of the Lipophosphoglycan from Leishmania (Leishmania major-like strains affect interaction with Phlebotomus papatasi and Lutzomyia longipalpis

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Agna Cristina Guimarães

2018-02-01

Full Text Available BACKGROUND Leishmania major is an Old World species causing cutaneous leishmaniasis and is transmitted by Phlebotomus papatasi and Phlebotomus duboscqi. In Brazil, two isolates from patients who never left the country were characterised as L. major-like (BH49 and BH121. Using molecular techniques, these isolates were indistinguishable from the L. major reference strain (FV1. OBJECTIVES We evaluated the lipophosphoglycans (LPGs of the strains and their behaviour in Old and New World sand fly vectors. METHODS LPGs were purified, and repeat units were qualitatively evaluated by immunoblotting. Experimental in vivo infection with L. major-like strains was performed in Lutzomyia longipalpis (New World, permissive vector and Ph. papatasi (Old World, restrictive or specific vector. FINDINGS The LPGs of both strains were devoid of arabinosylated side chains, whereas the LPG of strain BH49 was more galactosylated than that of strain BH121. All strains with different levels of galactosylation in their LPGs were able to infect both vectors, exhibiting colonisation of the stomodeal valve and metacyclogenesis. The BH121 strain (less galactosylated exhibited lower infection intensity compared to BH49 and FV1 in both vectors. MAIN CONCLUSIONS Intraspecific variation in the LPG of L. major-like strains occur, and the different galactosylation levels affected interactions with the invertebrate host.

Lower galactosylation levels of the Lipophosphoglycan from Leishmania (Leishmania) major-like strains affect interaction with Phlebotomus papatasi and Lutzomyia longipalpis.

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Guimarães, Agna Cristina; Nogueira, Paula Monalisa; Silva, Soraia de Oliveira; Sadlova, Jovana; Pruzinova, Katerina; Hlavacova, Jana; Melo, Maria Norma; Soares, Rodrigo Pedro

2018-01-01

BACKGROUND Leishmania major is an Old World species causing cutaneous leishmaniasis and is transmitted by Phlebotomus papatasi and Phlebotomus duboscqi. In Brazil, two isolates from patients who never left the country were characterised as L. major-like (BH49 and BH121). Using molecular techniques, these isolates were indistinguishable from the L. major reference strain (FV1). OBJECTIVES We evaluated the lipophosphoglycans (LPGs) of the strains and their behaviour in Old and New World sand fly vectors. METHODS LPGs were purified, and repeat units were qualitatively evaluated by immunoblotting. Experimental in vivo infection with L. major-like strains was performed in Lutzomyia longipalpis (New World, permissive vector) and Ph. papatasi (Old World, restrictive or specific vector). FINDINGS The LPGs of both strains were devoid of arabinosylated side chains, whereas the LPG of strain BH49 was more galactosylated than that of strain BH121. All strains with different levels of galactosylation in their LPGs were able to infect both vectors, exhibiting colonisation of the stomodeal valve and metacyclogenesis. The BH121 strain (less galactosylated) exhibited lower infection intensity compared to BH49 and FV1 in both vectors. MAIN CONCLUSIONS Intraspecific variation in the LPG of L. major-like strains occur, and the different galactosylation levels affected interactions with the invertebrate host.

Novos registros de Lutzomyia longipalpis (Lutz & Neiva, 1912(Diptera: Psychodidae na região Centro-Leste do estado de São Paulo, Brasil New records of Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera: Psychodidae in the Central East Region of São Paulo State, Brazil

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André Antonio Cutolo

2009-03-01

Full Text Available A incidência das leishmanioses tegumentar (LTA e visceral (LVA americanas, especialmente essa última, em hospedeiros caninos e humanos, encontra-se em expansão no Estado de São Paulo. Na vigilância epidemiológica dessas endemias, torna-se fundamental o conhecimento da distribuição e ecologia das diferentes espécies de flebotomíneos. Assim, a divulgação de novos registros de seus vetores é fundamental para apontar novas áreas de risco para a transmissão dessas doenças. Neste estudo, realizaram-se capturas de flebotomíneos em ambiente de mata, em diferentes localidades dos municípios de Ipeúna, Itirapina e Analândia, entre agosto e setembro de 2007. Foram capturados 248 flebotomíneos de nove espécies diferentes, em Ipeúna, seis e sete espécimes de duas espécies distintas coletados respectivamente em Itirapina e Analândia. A espécie mais abundante em Ipeúna foi Pintomyia pessoai (37,5%, seguida de P. fischeri (33,06% e Migonemyia migonei (16,53%. Essas três espécies são consideradas importantes vetores de LTA no território paulista. O registro de Lutzomyia longipalpis pela primeira vez em Ipeúna e Analândia e a confirmação de sua presença em Itirapina indicam risco de essabelecimento da LVA na área e a necessidade de mais estudos locais sobre sua ecologia, sobretudo em relação à ocupação de ambientes antrópicos.Cutaneous (LTA and Visceral (LVA American Leishmaniasis incidences are increasing in human and canine hosts, especially LVA, which is expanding its range through São Paulo State. Distribution and ecology knowledge of different sand fly species is essential for leishmaniasis epidemiology vigilance. The communication of new findings of its vectors is mandatory for risk determination for transmission of these illnesses. On this study sand flies were trapped in bushed areas, in different localities at rural areas of Ipeúna, Itirapina and Analândia counties, between August and September 2007. A total

Comparison of Model Predictions and Laboratory Observations of Transgene Frequencies in Continuously-Breeding Mosquito Populations

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Valerio, Laura; North, Ace; Collins, C. Matilda; Mumford, John D.; Facchinelli, Luca; Spaccapelo, Roberta; Benedict, Mark Q.

2016-01-01

The persistence of transgenes in the environment is a consideration in risk assessments of transgenic organisms. Combining mathematical models that predict the frequency of transgenes and experimental demonstrations can validate the model predictions, or can detect significant biological deviations that were neither apparent nor included as model parameters. In order to assess the correlation between predictions and observations, models were constructed to estimate the frequency of a transgene causing male sexual sterility in simulated populations of a malaria mosquito Anopheles gambiae that were seeded with transgenic females at various proportions. Concurrently, overlapping-generation laboratory populations similar to those being modeled were initialized with various starting transgene proportions, and the subsequent proportions of transgenic individuals in populations were determined weekly until the transgene disappeared. The specific transgene being tested contained a homing endonuclease gene expressed in testes, I-PpoI, that cleaves the ribosomal DNA and results in complete male sexual sterility with no effect on female fertility. The transgene was observed to disappear more rapidly than the model predicted in all cases. The period before ovipositions that contained no transgenic progeny ranged from as little as three weeks after cage initiation to as long as 11 weeks. PMID:27669312

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 'Natural Laboratory', a tool for deciphering growth, lifetime and population dynamics in larger benthic foraminifera

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Hohenegger, Johann

2015-04-01

The shells of symbiont-bearing larger benthic Foraminifera (LBF) represent the response to physiological requirements in dependence of environmental conditions. All compartments of the shell such as chambers and chamberlets accommodate the growth of the cell protoplasm and are adaptations for housing photosymbiotic algae. Investigations on the biology of LBF were predominantly based on laboratory studies. The lifetime of LBF under natural conditions is still unclear. LBF, which can build >100 chambers during their lifetime, are thought to live at least one year under natural conditions. This is supported by studies on population dynamics of eulittoral foraminifera. In species characterized by a time-restricted single reproduction period the mean size of specimens increases from small to large during lifetime simultaneously reducing individual number. This becomes more complex when two or more reproduction times are present within a one-year cycle leading to a mixture of abundant small individuals with few large specimens during the year, while keeping mean size more or less constant. This mixture is typical for most sublittoral megalospheric (gamonts or schizonts) LBF. Nothing is known on the lifetime of agamonts, the diploid asexually reproducing generation. In all hyaline LBF it is thought to be significantly longer than 1 year based on the large size and considering the mean chamber building rate of the gamont/schizonts. Observations on LBF under natural conditions have not been performed yet in the deeper sublittoral. This reflects the difficulties due to intense hydrodynamics that hinder deploying technical equipment for studies in the natural environment. Therefore, studying growth, lifetime and reproduction of sublittoral LBF under natural conditions can be performed using the so-called 'natural laboratory' in comparison with laboratory investigations. The best sampling method in the upper sublittoral from 5 to 70 m depth is by SCUBA diving. Irregular

Race, populations, and genomics: Africa as laboratory.

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Braun, Lundy; Hammonds, Evelynn

2008-11-01

Much of the recent debate over race, genetics, and health has focused on the extent to which typological notions of race have biological meaning. Less attention, however, has been paid to the assumptions about the nature of "populations" that both inform contemporary biological and medical research and that underlie the concept of race. Focusing specifically on Africa in the 1930s and 1940s, this paper explores the history of how fluid societies were transformed into bounded units amenable to scientific analysis. In the so-called "Golden Age of Ethnography," university-trained social anthropologists, primarily from Britain and South Africa, took to the field to systematically study, organize, and order the world's diverse peoples. Intent on creating a scientific methodology of neutral observation, they replaced amateur travelers, traders, colonial administrators, and missionaries as authoritative knowledge producers about the customs, beliefs, and languages of indigenous peoples. At the same time, linguists were engaged in unifying African languages and mapping language onto primordial "tribal" territories. We argue that the notion of populations or "tribes" as discrete units suitable for scientific sampling and classification emerged in the 1930s and 1940s with the ethnographic turn in social anthropology and the professionalization and institutionalization of linguistics in Western and South African universities. Once named and entered into international atlases and databases by anthropologists in the U.S., the existence of populations as bounded entities became self-evident, thus setting the stage for their use in large-scale population genetic studies and the contemporary reinvigoration of broad claims of difference based on population identification.

Comparison of Model Predictions and Laboratory Observations of Transgene Frequencies in Continuously-Breeding Mosquito Populations

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Laura Valerio

2016-09-01

Full Text Available The persistence of transgenes in the environment is a consideration in risk assessments of transgenic organisms. Combining mathematical models that predict the frequency of transgenes and experimental demonstrations can validate the model predictions, or can detect significant biological deviations that were neither apparent nor included as model parameters. In order to assess the correlation between predictions and observations, models were constructed to estimate the frequency of a transgene causing male sexual sterility in simulated populations of a malaria mosquito Anopheles gambiae that were seeded with transgenic females at various proportions. Concurrently, overlapping-generation laboratory populations similar to those being modeled were initialized with various starting transgene proportions, and the subsequent proportions of transgenic individuals in populations were determined weekly until the transgene disappeared. The specific transgene being tested contained a homing endonuclease gene expressed in testes, I-PpoI, that cleaves the ribosomal DNA and results in complete male sexual sterility with no effect on female fertility. The transgene was observed to disappear more rapidly than the model predicted in all cases. The period before ovipositions that contained no transgenic progeny ranged from as little as three weeks after cage initiation to as long as 11 weeks.

Comparison of longevity between a laboratory strain and a natural population of Anastrepha Fraterculus (Diptera: Tephritidae) under field cage conditions

International Nuclear Information System (INIS)

Gomez Cendra, P.; Vilardi, J.; Segura, D.; Cladera, J.; Allinghi, A.

2007-01-01

The South American fruit fly Anastrepha fraterculus (Wiedemann) is one of the most destructive fruit pests in this region, infesting major fruit crops. Implementation of the sterile insect technique (SIT) as part of an area-wide integrated approach against this species requires information on the survival of mass-reared and sterilized insects in the field and their ability to mate with wild females. The survival rates in field cages of both non-irradiated and irradiated laboratory flies were compared with that of wild flies. Both types of laboratory flies survived longer than their wild counterparts over the 8 days under the experimental conditions. The irradiation dose (70 Gy) did not affect survival of the laboratory reared flies. Our results improve the prospect of integrating the SIT into the control of A. fraterculus populations in Argentina. (author) [es

Itinerant radiometric laboratory (IRL-76)

International Nuclear Information System (INIS)

Dolgirev, E.I.; Domaratskij, V.P.; Kostikov, Yu.I.

1978-01-01

A mobile radiometric laboratory for routine radiation monitoring of the environment, personnel, and population is described. As compared to the previous models, this one incorporates a number of new features and is more informative and versatile. The design and main technical and operating characteristics of the laboratory are detailed

Effect of Leishmania spp infection on the survival, life expectancy, fecundity and fertility of Lutzomyia longipalpiss.l. and Lutzomyia pseudolongipalpis

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Irma Fatima Agrela

2015-08-01

Full Text Available We evaluated the effects of Leishmaniaspp infection on several population parameters of Lutzomyia longipalpis sensu lato andLutzomyia pseudolongipalpis, vectors of visceral leishmaniasis in Venezuela, under experimental conditions during the first post-feeding period. Females of both species were allowed to feed and engorge on a suspension of fresh washed human red blood cells in foetal calf serum. These blood cells were either non-infected or infected with one of the fourLeishmaniaspp strains and were offered through a chicken skin membrane. The longevity, life expectancy and the fecundity of uninfected flies were similar in both species, but the fertility was significantly lower in uninfected Lu. longipalpis females. In all cases, the infection of Lu. longipalpis and Lu. pseudolongipalpis by the Leishmaniastrains resulted in significant detrimental effects, which exerted a fitness cost expressed by reduced survival and life expectancy, as well as decreased fertility and fecundity compared with the control groups. Nevertheless, differences in these parameters were observed between these vector species depending on whether they were infected with the autochthonous Venezuelan Leishmania infantum strain (NESA or the Brazilian reference strain (PP75. The experimental data obtained agree with field data on the natural infection of these vector species and the significance of this scenario is discussed.

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

Creating 21st-Century Laboratories and Classrooms for Improving Population Health: A Call to Action for Academic Medical Centers.

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DeVoe, Jennifer E; Likumahuwa-Ackman, Sonja; Shannon, Jackilen; Steiner Hayward, Elizabeth

2017-04-01

Academic medical centers (AMCs) in the United States built world-class infrastructure to successfully combat disease in the 20th century, which is inadequate for the complexity of sustaining and improving population health. AMCs must now build first-rate 21st-century infrastructure to connect combating disease and promoting health. This infrastructure must acknowledge the bio-psycho-social-environmental factors impacting health and will need to reach far beyond the AMC walls to foster community "laboratories" that support the "science of health," complementary to those supporting the "science of medicine"; cultivate community "classrooms" to stimulate learning and discovery in the places where people live, work, and play; and strengthen bridges between academic centers and these community laboratories and classrooms to facilitate bidirectional teaching, learning, innovation, and discovery.Private and public entities made deep financial investments that contributed to the AMC disease-centered approach to clinical care, education, and research in the 20th century. Many of these same funders now recognize the need to transform U.S. health care into a system that is accountable for population health and the need for a medical workforce equipped with the skills to measure and improve health. Innovative ideas about communities as centers of learning, the importance of social factors as major determinants of health, and the need for multidisciplinary perspectives to solve complex problems are not new; many are 20th-century ideas still waiting to be fully implemented. The window of opportunity is now. The authors articulate how AMCs must take bigger and bolder steps to become leaders in population health.

Crowded growth leads to the spontaneous evolution of semistable coexistence in laboratory yeast populations.

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Frenkel, Evgeni M; McDonald, Michael J; Van Dyken, J David; Kosheleva, Katya; Lang, Gregory I; Desai, Michael M

2015-09-08

Identifying the mechanisms that create and maintain biodiversity is a central challenge in biology. Stable diversification of microbial populations often requires the evolution of differences in resource utilization. Alternatively, coexistence can be maintained by specialization to exploit spatial heterogeneity in the environment. Here, we report spontaneous diversification maintained by a related but distinct mechanism: crowding avoidance. During experimental evolution of laboratory Saccharomyces cerevisiae populations, we observed the repeated appearance of "adherent" (A) lineages able to grow as a dispersed film, in contrast to their crowded "bottom-dweller" (B) ancestors. These two types stably coexist because dispersal reduces interference competition for nutrients among kin, at the cost of a slower maximum growth rate. This tradeoff causes the frequencies of the two types to oscillate around equilibrium over the course of repeated cycles of growth, crowding, and dispersal. However, further coevolution of the A and B types can perturb and eventually destroy their coexistence over longer time scales. We introduce a simple mathematical model of this "semistable" coexistence, which explains the interplay between ecological and evolutionary dynamics. Because crowded growth generally limits nutrient access in biofilms, the mechanism we report here may be broadly important in maintaining diversity in these natural environments.

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

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.

Modelling population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions

Energy Technology Data Exchange (ETDEWEB)

Lance, Emilie [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Alonzo, Frederic, E-mail: frederic.alonzo@irsn.fr [Laboratoire d' ecotoxicologie des radionucleides (LECO) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Garcia-Sanchez, Laurent [Laboratoire de biogeochimie, biodisponibilite et transferts des radionucleides (L2BT) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Beaugelin-Seiller, Karine; Garnier-Laplace, Jacqueline [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France)

2012-07-01

We modelled population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions. We used Leslie matrices to combine life-history characteristics (duration of life stages, survival and fecundity rates) and dose rate-response curves for hatching, survival and reproduction fitted on effect data from the FREDERICA database. Changes in net reproductive rate R{sub 0} (offspring per individual) and asymptotic population growth rate {lambda} (dimensionless) were calculated over a range of dose rates in two marine polychaetes (Neanthes arenaceodentata and Ophryotrocha diadema) and a freshwater gastropod (Physa heterostropha). Sensitivities in R{sub 0} and {lambda} to changes in life-history traits were analysed in each species. Results showed that fecundity has the strongest influence on R{sub 0}. A delay in age at first reproduction is most critical for {lambda} independent of the species. Fast growing species were proportionally more sensitive to changes in individual endpoints than slow growing species. Reduction of 10% in population {lambda} were predicted at dose rates of 6918, 5012 and 74,131 {mu}Gy{center_dot}h{sup -1} in N. arenaceodentata, O. diadema and P. heterostropha respectively, resulting from a combination of strong effects on several individual endpoints in each species. These observations made 10%-reduction in {lambda} a poor criterion for population protection. The lowest significant changes in R{sub 0} and {lambda} were respectively predicted at a same dose rate of 1412 {mu}Gy h{sup -1} in N. arenaceodentata, at 760 and 716 {mu}Gy h{sup -1} in O. diadema and at 12,767 and 13,759 {mu}Gy h{sup -1} in P. heterostropha. These values resulted from a combination of slight but significant changes in several measured endpoints and were lower than effective dose rates calculated for the individual level in O. diadema and P. heterostropha. The relevance of the experimental dataset (external irradiation rather

Factors controlling the population size of microbes in groundwater from AECL's Underground Research Laboratory

Energy Technology Data Exchange (ETDEWEB)

Stroes-Gascoyne, S.; Hamon, C. [Atomic Energy of Canada Limited, Whiteshell Labs., Pinawa, Manitoba (Canada); Mills, K. [University of Saskatoon, Saskatoon, SK (Canada); Rana, S.; Vaidyanathan, S. [Deep River Science Academy, Whiteshell Campus Summer 1997, Pinawa, Manitoba (Canada)

2001-01-01

Microbial populations in groundwaters from AECL's Underground Research Laboratory (URL) range from 10{sup 3} to 10{sup 5} cells/mL. Based on the total dissolved organic carbon (DOC), nitrate and phosphate content of these waters, populations of about 10{sup 5} to 10{sup 7} cells/mL should be possible. Upon storage of groundwater samples, total cell counts generally increase and viable cell counts always increase. A study was undertaken to determine what controls the in situ microbial population size in groundwater and what causes this population to grow upon sampling. Fresh URL groundwater was filter-sterilized, inoculated with small quantities of the unaltered water and incubated in the absence and presence of added nutrients (nitrate, phosphate and glucose). Unfiltered groundwater and R2A growth medium inoculated with unaltered groundwater, were also incubated. Microbial changes over time were followed by total and viable (on R2A medium) cell counts. Results showed that in the absence of any nutrient addition, populations grew to between 5 x 10{sup 5} to 4 x 10{sup 6} cells/mL, regardless of the initial size of the population ({approx}10{sup 1} to 10{sup 4} cells/mL), suggesting that nutrients for growth were available in the unamended groundwater. It was hypothesized that the original groundwater population was in 'equilibrium' with the underground environment, which likely included a large population of sessile cells in biofilms on fracture surfaces. Sampling of the groundwater removed the large demand on nutrient supplies by the sessile population which subsequently allowed the planktonic population to grow to a new 'equilibrium' with the available nutrients in the sample bottles. Addition of single nutrients (C, N or P) did not increase cell numbers, suggesting that more than one nutrient is limiting growth. Glucose was used very efficiently aerobically in the presence of both added N and P, but somewhat less under anaerobic

Effects of seven diets on the population dynamics of laboratory cultured Tisbe holothuriae Humes (Copepoda, Harpacticoida)

Science.gov (United States)

Miliou, H.; Moraïtou-Apostolopoulou, M.

1991-09-01

The harpacticoid copepod Tisbe holothuriae was collected from Saronicos Gulf (Greece) and reared under constant laboratory conditions. In order to study the effects of food on the population dynamics, seven diets were tested: the seaweed Ulva; five artificial compound feeds: the liquid Fryfood® (Waterlife), a powder of Mytilus, yeast, soya and Spirulina, respectively; and a mixed diet consisting of Ulva and Fryfood. The life cycle parameters (mortality, sex ratio, generation time, offspring production) were measured, and the demographic variables [mean generation time (T), net reproductive rate (Ro), and intrinsic rate of natural increase (rm)] were determined. As to their efficiency regarding population dynamics, the diets ranked as follows: (1) Ulva+Fryfood, (2), Ulva, (3) Fryfood, (4) Mytilus, (5) soya, (6) yeast, and (7) Spirulina. In this order they cause a progressive increase of both larval mortality and generation time, a progressive decrease of sex ratio, number of offspring per egg sac, number of egg sacs per female and, consequently, of Ro and rm. The observed differences between diets were most pronounced with respect to offspring production. Of the compound diets, those containing animal extracts were more efficient than those containing vegetable materials. Ulva plays an important role in the nutrition of T. holothuriae, favouring offspring production as well as larval survival, development and pigmentation. Ulva in combination with Fryfood led to a greater copepodid survival and offspring production. This mixed diet proved to be the most favourable for rearing the Greek population of t. holothuriae, resulting in an efficient intrinsic rate of natural increase (rm=0.304) of the population.

Wellness Center use at Los Alamos National Laboratory: a descriptive study

Energy Technology Data Exchange (ETDEWEB)

Wiggs, L.D.; Wilkinson, G.S.; Weber, C.

1985-10-01

This study describes employee participation during the first six months of the Los Alamos National Laboratory's corporate Wellness Program. We describe temporal patterns of use, preferred activities, frequency of use, and characteristics of employees participating in Wellness activities. Characteristics of Wellness participants are compared with characteristics of the Laboratory population. During this period the Wellness Center, a multi-use facility that houses Wellness Program activities, had 17,352 visits. Employees visiting the Wellness Center were typical of the Laboratory population in their racial and ethnic characteristics, but different in their sex and age composition. Wellness participants were younger and more likely to be female than the Laboratory population. 6 refs., 19 tabs.

Calgary Laboratory Services

Directory of Open Access Journals (Sweden)

James R. Wright MD, PhD

2015-12-01

Full Text Available Calgary Laboratory Services provides global hospital and community laboratory services for Calgary and surrounding areas (population 1.4 million and global academic support for the University of Calgary Cumming School of Medicine. It developed rapidly after the Alberta Provincial Government implemented an austerity program to address rising health care costs and to address Alberta’s debt and deficit in 1994. Over roughly the next year, all hospital and community laboratory test funding within the province was put into a single budget, fee codes for fee-for-service test billing were closed, roughly 40% of the provincial laboratory budget was cut, and roughly 40% of the pathologists left the province of Alberta. In Calgary, in the face of these abrupt changes in the laboratory environment, private laboratories, publicly funded hospital laboratories and the medical school department precipitously and reluctantly merged in 1996. The origin of Calgary Laboratory Services was likened to an “unhappy shotgun marriage” by all parties. Although such a structure could save money by eliminating duplicated services and excess capacity and could provide excellent city-wide clinical service by increasing standardization, it was less clear whether it could provide strong academic support for a medical school. Over the past decade, iterations of the Calgary Laboratory Services model have been implemented or are being considered in other Canadian jurisdictions. This case study analyzes the evolution of Calgary Laboratory Services, provides a metric-based review of academic performance over time, and demonstrates that this model, essentially arising as an unplanned experiment, has merit within a Canadian health care context.

Predicted altitudinal shifts and reduced spatial distribution of Leishmania infantum vector species under climate change scenarios in Colombia.

Science.gov (United States)

González, Camila; Paz, Andrea; Ferro, Cristina

2014-01-01

. longipalpis and confining L. evansi to certain regions in the Caribbean Coast. Altitudinal shifts have been reported for cutaneous leishmaniasis vectors in Colombia and Peru. Here, we predict the same outcome for VL vectors in Colombia. Changes in spatial distribution patterns could be affecting local abundances due to climatic pressures on vector populations thus reducing the incidence of human cases. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

Hematology laboratory standardization: a plan for harmonization in Asia.

Science.gov (United States)

Bunyaratvej, A; Tatsumi, N; Funahara, Y

1999-01-01

Hematology laboratory is generally required in the hospital. At the macroscale, hematology laboratories have served a large number of population. In Asia, more than 3,000 million people are potentially to use the hematology laboratory service, particularly the complete blood count. Since 1970s, automated technology has been introduced to Asia and as years passed by, technology diversity is increasing. However, there are considerable number of hematology laboratories that have no automated machine. They are still relied on manual technology which is still variable in spectrophotometer for hemoglobin determination, centrifuge for hematocrit and diluting pipet for cell counting. In particular, blood smear preparation and interpretation are very difficult to control for standardization from person to person and laboratory to laboratory. Different methodology and a large population in the huge geographical area in Asia, the agreement of standard criteria is greatly important. This report has shown strategy and action plan to reach the goal of hematology laboratory standardization in Asia.

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

Science.gov (United States)

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.

Characterizing the Laboratory Market

Energy Technology Data Exchange (ETDEWEB)

Shehabi, Arman [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ganeshalingam, Mohan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); DeMates, Lauren [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mathew, Paul [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sartor, Dale [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-04-11

Laboratories are estimated to be 3-5 times more energy intensive than typical office buildings and offer significant opportunities for energy use reductions. Although energy intensity varies widely, laboratories are generally energy intensive due to ventilation requirements, the research instruments used, and other health and safety concerns. Because the requirements of laboratory facilities differ so dramatically from those of other buildings, a clear need exists for an initiative exclusively targeting these facilities. The building stock of laboratories in the United States span different economic sectors, include governmental and academic institution, and are often defined differently by different groups. Information on laboratory buildings is often limited to a small subsection of the total building stock making aggregate estimates of the total U.S. laboratories and their energy use challenging. Previous estimates of U.S. laboratory space vary widely owing to differences in how laboratories are defined and categorized. A 2006 report on fume hoods provided an estimate of 150,000 laboratories populating the U.S. based in part on interviews of industry experts, however, a 2009 analysis of the 2003 Commercial Buildings Energy Consumption Survey (CBECS) generated an estimate of only 9,000 laboratory buildings. This report draws on multiple data sources that have been evaluated to construct an understanding of U.S. laboratories across different sizes and markets segments. This 2016 analysis is an update to draft reports released in October and December 2016.

Plasma creatinine in dogs: intra- and inter-laboratory variation in 10 European veterinary laboratories

Directory of Open Access Journals (Sweden)

Ulleberg Thomas

2011-04-01

Full Text Available Abstract Background There is substantial variation in reported reference intervals for canine plasma creatinine among veterinary laboratories, thereby influencing the clinical assessment of analytical results. The aims of the study was to determine the inter- and intra-laboratory variation in plasma creatinine among 10 veterinary laboratories, and to compare results from each laboratory with the upper limit of its reference interval. Methods Samples were collected from 10 healthy dogs, 10 dogs with expected intermediate plasma creatinine concentrations, and 10 dogs with azotemia. Overlap was observed for the first two groups. The 30 samples were divided into 3 batches and shipped in random order by postal delivery for plasma creatinine determination. Statistical testing was performed in accordance with ISO standard methodology. Results Inter- and intra-laboratory variation was clinically acceptable as plasma creatinine values for most samples were usually of the same magnitude. A few extreme outliers caused three laboratories to fail statistical testing for consistency. Laboratory sample means above or below the overall sample mean, did not unequivocally reflect high or low reference intervals in that laboratory. Conclusions In spite of close analytical results, further standardization among laboratories is warranted. The discrepant reference intervals seem to largely reflect different populations used in establishing the reference intervals, rather than analytical variation due to different laboratory methods.

Environmental monitoring report: Sandia Laboratories, 1976

International Nuclear Information System (INIS)

Simmons, T.N.

1977-04-01

Water and vegetation are monitored to determine Sandia Laboratories impact on the surrounding environment. Nonradioactive pollutants released are reported. Radioactive effluents are also reported and their person-rem contribution to the Albuquerque population is calculated. The environmental monitoring for calendar year 1976 shows that concentrations of radioactive materials in the Albuquerque area are typical of natural background for the area. An exception is a single onsite location where slightly abnormal uranium concentrations are expected. An estimated 0.044 person-rem Albuquerque area (80 km radius) population dose commitment results from calculated Sandia Laboratories releases. Over the same area 57,000 person-rem is accumulated from natural background. There were no measurable offsite radioactive effluent releases in CY 1976

Isolation and Identification of 9-methylgermacrene-B as the Putative Sex Pheromone of Lutzomyia cruzi (Mangabeira, 1938 (Diptera: Psychodidae

Directory of Open Access Journals (Sweden)

Brazil Reginaldo P

2002-01-01

Full Text Available Lutzomyia (Lutzomyia cruzi has been named as a probable vector of Leishmania chagasi in Corumbá, Mato Grosso do Sul, Brazil. Taxonomically L. cruzi is closely related to the L. longipalpis species complex. Females of L. cruzi and L. longipalpis are morphologically indistinguishable and associated males must be examined carefully to confirm identifications. Chemical analysis hexane extracts of male L. cruzi has revealed the presence of a 9-methylgermacrene-B (C16, a homosesquiterpene (mw 218 previously shown to be the sex pheromone of one of the members of the L. longipalpis species complex.

Comparison of Estrogen Receptor Assay Results from Pathology Reports with Results from Central Laboratory Testing: Implications for Population-Based Studies of Breast Cancer

Science.gov (United States)

Collins, LC; Marotti, J; Baer, HJ; Deitz, AC; Colditz, GA; Tamimi, RM

2014-01-01

Population-based studies of women with breast cancer commonly utilize information culled from pathology reports rather than central pathology review. The reliability of this information, particularly with regard to tumor biomarker results, is of concern. To address this, we evaluated the concordance between estrogen receptor (ER) results as determined from the original pathology reports and ER results obtained on the same specimens following testing in a single laboratory. Tissue microarrays (TMAs) were constructed from paraffin blocks of 3,167 breast cancers that developed in women enrolled in the Nurses’ Health Study. ER immunostains were performed on all TMA sections in single run. Results of ER immunostains performed on the TMA sections were compared with ER assay results abstracted from pathology reports. Among 1,851 cases of invasive breast cancer in which both ER results from pathology reports and central ER test results were available, the reported ER status and the ER status as determined from immunostains on TMAs were in agreement in 1,651 cases (87.3 %; kappa value 0.64, ppathology reports is a reasonable, albeit imperfect, alternative to central laboratory ER testing for large, population-based studies of patients with breast cancer. PMID:18230800

Medical Services Annual Historical Report - AMEDD Activities, Calendar Year 1981.

Science.gov (United States)

1981-01-01

Research Triangle Park, N.C., el. d. Eggs of the phlebotomine sandfly Lutzomyia longipalpis for establishment of new colonies for research were... Lutzomyia longipalpis (Diptera, Psychodidae)," 12th Annual Meeting of the Society of Vector Ecologist, Fresno, CA, 21-22 Jan 81. 43. CPT C.T. hite, MS

Environmental monitoring report, Sandia Laboratories 1975

International Nuclear Information System (INIS)

Holley, W.L.; Simmons, T.N.

1976-04-01

Water and vegetation are monitored to determine Sandia Laboratories impact on the surrounding environment. Nonradioactive pollutants released are reported. Radioactive effluents are also reported and their person-rem contribution to the population is calculated

Population dynamics and habitat sharing of natural populations of Caenorhabditis elegans and C. briggsae

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Félix Marie-Anne

2012-06-01

Full Text Available Abstract Background The nematode Caenorhabditis elegans is a major model organism in laboratory biology. Very little is known, however, about its ecology, including where it proliferates. In the past, C. elegans was mainly isolated from human-made compost heaps, where it was overwhelmingly found in the non-feeding dauer diapause stage. Results C. elegans and C. briggsae were found in large, proliferating populations in rotting plant material (fruits and stems in several locations in mainland France. Both species were found to co-occur in samples isolated from a given plant species. Population counts spanned a range from one to more than 10,000 Caenorhabditis individuals on a single fruit or stem. Some populations with an intermediate census size (10 to 1,000 contained no dauer larvae at all, whereas larger populations always included some larvae in the pre-dauer or dauer stages. We report on associated micro-organisms, including pathogens. We systematically sampled a spatio-temporally structured set of rotting apples in an apple orchard in Orsay over four years. C. elegans and C. briggsae were abundantly found every year, but their temporal distributions did not coincide. C. briggsae was found alone in summer, whereas both species co-occurred in early fall and C. elegans was found alone in late fall. Competition experiments in the laboratory at different temperatures show that C. briggsae out-competes C. elegans at high temperatures, whereas C. elegans out-competes C. briggsae at lower temperatures. Conclusions C. elegans and C. briggsae proliferate in the same rotting vegetal substrates. In contrast to previous surveys of populations in compost heaps, we found fully proliferating populations with no dauer larvae. The temporal sharing of the habitat by the two species coincides with their temperature preference in the laboratory, with C. briggsae populations growing faster than C. elegans at higher temperatures, and vice at lower temperatures.

Canine visceral leishmaniasis in the metropolitan area of São Paulo: Pintomyia fischeri as potential vector of Leishmania infantum

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Galvis-Ovallos Fredy

2017-01-01

Full Text Available American visceral leishmaniasis is a zoonosis caused by Leishmania infantum and transmitted mainly by Lutzomyia longipalpis. However, canine cases have been reported in the absence of this species in the Greater São Paulo region, where Pintomyia fischeri and Migonemyia migonei are the predominant species. This raises the suspicion that they could be acting as vectors. Therefore, this study sought to investigate specific vector capacity parameters of these species and to compare them with those of Lu. longipalpis s.l. Among these parameters the blood feeding rate, the survival, and the susceptibility to the development of Le. infantum were evaluated for the three species, and the attractiveness of dogs to Pi. fischeri and Mg. migonei was evaluated. The estimated interval between blood meals was shorter for Lu. longipalpis s.l, followed by Pi. fischeri and Mg. migonei. The infection rate with Le. infantum flagellates in Lu. longipalpis was 9.8%, in Pi. fischeri 4.8%, and in Mg. migonei nil. The respective infective life expectancies (days of Lu. longipalpis, Mg. migonei, and Pi. fischeri were 2.4, 1.94, and 1.68. Both Pi. fischeri and Mg. migonei were captured in the kennel with a predominance (95% of Pi. fischeri. Considering the great attractiveness of dogs to Pi. fischeri, its susceptibility to infection by Le. infantum, infective life expectancies, and predominance in Greater São Paulo, this study presents evidence of Pi. fischeri as a potential vector of this parasite in the region.

Adult Hematology and Clinical Chemistry Laboratory Reference Ranges in a Zimbabwean Population.

Science.gov (United States)

Samaneka, Wadzanai P; Mandozana, Gibson; Tinago, Willard; Nhando, Nehemiah; Mgodi, Nyaradzo M; Bwakura-Dangarembizi, Mutsawashe F; Munjoma, Marshall W; Gomo, Zvenyika A R; Chirenje, Zvavahera M; Hakim, James G

2016-01-01

Laboratory reference ranges used for clinical care and clinical trials in various laboratories in Zimbabwe were derived from textbooks and research studies conducted more than ten years ago. Periodic verification of these ranges is essential to track changes over time. The purpose of this study was to establish hematology and chemistry laboratory reference ranges using more rigorous methods. A community-based cross-sectional study was carried out in Harare, Chitungwiza, and Mutoko. A multistage sampling technique was used. Samples were transported from the field for analysis at the ISO15189 certified University of Zimbabwe-University of California San Francisco Central Research Laboratory. Hematology and clinical chemistry reference ranges lower and upper reference limits were estimated at the 2.5th and 97.5th percentiles respectively. A total of 769 adults (54% males) aged 18 to 55 years were included in the analysis. Median age was 28 [IQR: 23-35] years. Males had significantly higher red cell counts, hemoglobin, hematocrit, and mean corpuscular hemoglobin compared to females. Females had higher white cell counts, platelets, absolute neutrophil counts, and absolute lymphocyte counts compared to males. There were no gender differences in eosinophils, monocytes, and absolute basophil count. Males had significantly higher levels of urea, sodium, potassium, calcium, creatinine, amylase, total protein, albumin and liver enzymes levels compared to females. Females had higher cholesterol and lipase compared with males. There are notable differences in the white cell counts, neutrophils, cholesterol, and creatinine kinase when compared with the currently used reference ranges. Data from this study provides new country specific reference ranges which should be immediately adopted for routine clinical care and accurate monitoring of adverse events in research studies.

Dynamic insecticide susceptibility changes in Florida populations of Diaphorina citri (Hemiptera: Psyllidae).

Science.gov (United States)

Tiwari, Siddharth; Killiny, Nabil; Stelinski, Lukasz L

2013-02-01

Five field populations of Diaphorina citri Kuwayama from various regions of Florida were evaluated in 2011 for resistance to commonly used insecticides. Three diagnostic doses (LD50, LD75, and LD95), developed in 2009 using a laboratory susceptible population, were used to measure changes in susceptibility levels of field-collected populations as compared with a susceptible laboratory population. Further reductions in the susceptibility levels of D. citri to chlorpyriphos and fenpropathrin were determined, compared with results obtained in 2010. Mean percent mortality obtained from all five locations was significantly lower than observed with the laboratory susceptible population for all insecticides tested. Previously, expression of five CYP4 genes was implicated in contributing to insecticide metabolism in D. citri. In the current study, we compared the relative expression of these five CYP4 genes and their associated levels of protein expression among field-collected and laboratory susceptible populations. Expression of all CYP4 genes investigated was higher in field-collected populations when normalized against the laboratory susceptible population. There was an increased signal of a band corresponding to a 45 kDa protein in four of the five field populations as measured by the Western blot assay, which suggests increased production of cytochrome P450 enzymes. The current results indicate that insecticide resistance continues to increase in Florida populations ofD. citri, particularly to chlorpyriphos and fenpropathrin. However, there was no further decrease in susceptibility of Florida populations of D. citri to neonicotinoid insecticides in 2011 as compared with previous years.

[Neurologic and laboratory findings in a population of an endemic area for taeniasis-cysticercosis, Lagamar, MG, Brazil (1992-1993)].

Science.gov (United States)

Silva-Vergara, M L; Vieira, C de O; Castro, J H; Micheletti, L G; Otaño, A S; Franquini júnior, J; Cabral, M; Leboreiro, A; Marques, J O; de Souza, W F

1994-01-01

A clinic-epidemiological enquiry was conducted on in an endemic area for teniasis-cysticercosis. From the whole population 1080 (32.2%) individuals were examined. We found 198 (18.3%) individuals referring teniasis-bearing in the past, and 103 (9.5%) affirming to have had convulsions, either in the past or present. From the last group, 39 (37.8%) indicated that the crisis had begun in adulthood. From the group of patients presenting convulsions, 62 (62%) had laboratory tests performed. Computed tomography showed intracranial calcifications in 21 (33.8%) patients, variable in number and location, suggesting neurocysticercosis and no evidence of disease activity. Electroencephalograms showed abnormal waves in 21 (33.8%) patients and cerebrospinal fluid analyses were altered in 27 (43.5%) cases, having detected eosinophils only in 3 (4.8%) patients. Spinal fluid tests for cysticercosis through enzyme linked immunosorbent assay (ELISA) or indirect immunofluorescence were taken in only 26 (41.9%) patients, obtaining positive results in 6 (23%) samples. Varying upward shifts of protein levels were found in spinal fluid analysis. Assuming that all epidemiologic risk factors for teniasis-cysticercosis in the studied region and its correlation with the laboratory alterations described in convulsing crisis, a prevalence of 1.9% for neurocysticercosis was found.

[Why medical consultation is needed in the clinical laboratory].

Science.gov (United States)

Kawai, T

1998-10-01

During the 20th century, at least until the 1980s, clinical laboratory practice had been rapidly expanded, mainly because of a significant advancement in medicine as a whole and also in laboratory technology. However, recent economic changes in health care environment worldwide have been influencing greatly future trends in clinical laboratory practice. Four major macroeconomic forces drive change in clinical laboratory practice as follows; (1) Increasing cost of health care, (2) Implications of an aging population, (3) Social change in the patient population, and (4) Explosion of new technologies. Obviously, the increasing cost of health care is the primary driver. Considering a rapid change in the health care environment, clearly there are two separate pathways to be considered with regard to future modes of delivering patient care services through the clinical laboratory: commercial independent laboratories and hospital laboratories. In most hospital laboratories, in addition to high-quality, accurate and precise laboratory data being delivered through automated informatics in a timely fashion, laboratory physicians and other laboratorians should be available 24 hours a day and 7 days a week. The primary purpose of this approach is to develop a system in which the physician can order the most efficient number of tests, which will provide the maximum amount of clinically relevant informations most rapidly and most accurately at the least cost to the patient. Laboratory physicians must play a key role particularly in hospital laboratories. Their most important roles include those of a professional supplier of laboratory results being useful for health care and clinically relevant, and that of a consultative role for primary care physicians and other co-medical staffs to make important medical decision, based on laboratory results obtained. Therefore, the Japan Society of Clinical Pathology started in 1990 in publishing a series of proposed guidelines for adequate

Sandia National Laboratories 1979 environmental monitoring report

International Nuclear Information System (INIS)

Simmons, T.N.

1980-04-01

Sandia National Laboratories in Albuquerque is located south of the city on two broad mesas. The local climate is arid continental. Radionuclides are released from five technical areas from the Laboratories' resarch activities. Sandia's environmental monitoring program searches for cesium-137, tritium, uranium, alpha emitters, and beta emitters in water, soil, air, and vegetation. No activity was found in public areas in excess of local background in 1979. The Albuquerque population receives only 0.076 person-rem (estimated) from airborne radioactive releases. While national security research is the laboratories' major responsibility, energy research is a major area of activity. Both these research areas cause radioactive releases

Adult Hematology and Clinical Chemistry Laboratory Reference Ranges in a Zimbabwean Population.

Directory of Open Access Journals (Sweden)

Wadzanai P Samaneka

Full Text Available Laboratory reference ranges used for clinical care and clinical trials in various laboratories in Zimbabwe were derived from textbooks and research studies conducted more than ten years ago. Periodic verification of these ranges is essential to track changes over time. The purpose of this study was to establish hematology and chemistry laboratory reference ranges using more rigorous methods.A community-based cross-sectional study was carried out in Harare, Chitungwiza, and Mutoko. A multistage sampling technique was used. Samples were transported from the field for analysis at the ISO15189 certified University of Zimbabwe-University of California San Francisco Central Research Laboratory. Hematology and clinical chemistry reference ranges lower and upper reference limits were estimated at the 2.5th and 97.5th percentiles respectively.A total of 769 adults (54% males aged 18 to 55 years were included in the analysis. Median age was 28 [IQR: 23-35] years. Males had significantly higher red cell counts, hemoglobin, hematocrit, and mean corpuscular hemoglobin compared to females. Females had higher white cell counts, platelets, absolute neutrophil counts, and absolute lymphocyte counts compared to males. There were no gender differences in eosinophils, monocytes, and absolute basophil count. Males had significantly higher levels of urea, sodium, potassium, calcium, creatinine, amylase, total protein, albumin and liver enzymes levels compared to females. Females had higher cholesterol and lipase compared with males. There are notable differences in the white cell counts, neutrophils, cholesterol, and creatinine kinase when compared with the currently used reference ranges.Data from this study provides new country specific reference ranges which should be immediately adopted for routine clinical care and accurate monitoring of adverse events in research studies.

Transmission-blocking interventions eliminate malaria from laboratory populations

OpenAIRE

Blagborough, A. M.; Churcher, T. S.; Upton, L. M.; Ghani, A. C.; Gething, P. W.; Sinden, R. E.

2013-01-01

Transmission-blocking interventions aim to reduce the prevalence of infection in endemic communities by targeting Plasmodium within the insect host. Although many studies have reported the successful reduction of infection in the mosquito vector, direct evidence that there is an onward reduction in infection in the vertebrate host is lacking. Here we report the first experiments using a population, transmission-based study of Plasmodium berghei in Anopheles stephensi to assess the impact of a...

One hundred and six years of population and community dynamics of Sonoran Desert Laboratory perennials

Science.gov (United States)

Rodriguez-Buritica, Susana; Raichle, Helen; Webb, Robert H.; Turner, Raymond M.; Venable, Larry

2013-01-01

This data set constitutes all information associated with the Spalding-Shreve permanent vegetation plots from 1906 through 2012, which is the longest-running plant monitoring program in the world. The program consists of detailed maps of all Sonoran Desert perennial plants in 30 permanent plots located on Tumamoc Hill, near Tucson, Arizona, USA. Most of these plots are 10 m × 10 m quadrats that were established by Volney Spalding and Forrest Shreve between 1906 and 1928. Analyses derived from these data have been pivotal in testing early theories on plant community succession, plant life history traits, plant longevity, and population dynamics. One of the major contributions of this data set is the species-specific demographic traits that derived from estimating individual plant trajectories for more than 106 years. Further use of these data might shed light on spatially explicit population and community dynamics, as well as long-term changes attributable to global change. Data presented here consist of digital versions of original maps created between 1906 and 1984 and digital data from recent censuses between 1993 and 2012. Attributes associated with these maps include location and coverage of all shrubs, and in some cases, plant height. In addition, we present plot-specific summaries of plant cover and density for each census year and all other information collected, including seedling counts, grass coverage, and annual species enumerations. We reference the repeat photography of these plots, which began in 1906; these images are stored at the Desert Laboratory Collection of Repeat Photography in Tucson. Initial data collection consisted of grid-mapping the plots manually on graph paper; starting in 1993, Total Stations (which allow a direct digitalization, and more accurate mapping) were used to survey root crowns and canopies.

Cancer incidence among workers at the Los Alamos National Laboratory

International Nuclear Information System (INIS)

Acquavella, J.J.; Wilkinson, G.S.; Wiggs, L.D.; Reyes-Waxweiler, M.; Key, C.R.; Tietjen, G.L.

1985-01-01

An analysis of cancer incidence among Los Alamos workers was reported at the Sixteenth Mid-Year Topical Symposium of the Health Physics Society. Cancer incidence was especially low among Anglo-American males for cancer of the lung and oral cancer, cancer sites commonly associated with cigarette smoking. No cases of cancer of the lung, oral cavity, pancreas, or bladder were observed among Anglo-American females in the population. Standardized incidence ratios for cancer of the breast and cancer of the uterine corpus exceeded one; however, these findings were not statistically significant. These findings are consistent with expectation for a population of high socioeconomic class, such as the Laboratory work force. Therefore, working conditions at the Laboratory do not appear to have affected cancer incidence in this population. 1 reference, 2 tables

The effect of X-radiation on a laboratory population of Drosophila melanogaster

International Nuclear Information System (INIS)

Sushzhenko, O.V.; Evdokimov, E.V.; Plekhanov, G.F.

1985-01-01

A study was made of the effect of X radiation in doses of 13 to 416 mC/kg on a Dr. melanogaster population heterogenous in fertility. In the case of weak effects (13 and 26 mC/kg) the responses were diverse which was attributed to genetic differences between individuals of a population. With strong effects, the response of the population was identical

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

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.

Global Clusters as Laboratories for Stellar Evolution

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Catelan, Marcio; Valcarce, Aldo A. R.; Sweigart, Allen V.

2010-01-01

Globular clusters have long been considered the closest approximation to a physicist's laboratory in astrophysics, and as such a near-ideal laboratory for (low-mass) stellar evolution, However, recent observations have cast a shadow on this long-standing paradigm, suggesting the presence of multiple populations with widely different abundance patterns, and - crucially - with widely different helium abundances as welL In this review we discuss which features of the Hertzsprung-Russell diagram may be used as helium abundance indicators, and present an overview of available constraints on the helium abundance in globular clusters,

Personal epistemological growth in a college chemistry laboratory environment

Science.gov (United States)

Keen-Rocha, Linda S.

The nature of this study was to explore changes in beliefs and lay a foundation for focusing on more specific features of reasoning related to personal epistemological and NOS beliefs in light of specific science laboratory instructional pedagogical practices (e.g., pre- and post-laboratory activities, laboratory work) for future research. This research employed a mixed methodology, foregrounding qualitative data. The total population consisted of 56 students enrolled in several sections of a general chemistry laboratory course, with the qualitative analysis focusing on the in-depth interviews. A quantitative NOS and epistemological beliefs measure was administered pre- and post-instruction. These measures were triangulated with pre-post interviews to assure the rigor of the descriptions generated. Although little quantitative change in NOS was observed from the pre-post NSKS assessment a more noticeable qualitative change was reflected by the participants during their final interviews. The NSKS results: the mean gain scores for the overall score and all dimensions, except for amoral were found to be significant at p ≤ .05. However there was a more moderate change in the populations' broader epistemological beliefs (EBAPS) which was supported during the final interviews. The EBAPS results: the mean gain scores for the overall score and all dimensions, except for the source of ability to learn were found to be significant at p ≤ .05. The participants' identified the laboratory work as the most effective instructional feature followed by the post-laboratory activities. The pre-laboratory was identified as being the least effective feature. The participants suggested the laboratory work offered real-life experiences, group discussions, and teamwork which added understanding and meaning to their learning. The post-laboratory was viewed as necessary in tying all the information together and being able to see the bigger picture. What one cannot infer at this point is

PCR para la confirmación de transmisión experimental de Leishmania chagasi a hámster sano por picadura de Lutzomyia longipalpis (Diptera: Psychodidae.

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Olga L. Cabrera

2003-06-01

Full Text Available Se evaluó la efectividad de la PCR como herramienta en la detección de la transmisión experimental de Leishmania chagasi a hámster, Mesocricetus auratus, por picadura del insecto vector. Dos pares de hámsteres sanos y anestesiados fueron colocados en jaulas que contenían hembras de Lutzomyia longipalpis. Previamente, las hembras se infectaron experimentalmente con Leishmania chagasi y la infección se confirmó por disección en una submuestra. A los 37 y 51 días después de la exposición a los insectos infectados, las biopsias de hígado y bazo de cada hámster se sometieron a examen directo al microscopio, histopatología y PCR. El ADN se extrajo con Chelex 100®; en la amplificación se utilizó un par de iniciadores específicos para la región conservada de los minicírculos del ADN de Leishmania. El producto amplificado se separó en geles de agarosa y se visualizó bajo luz UV. En tres de las cuatro biopsias se observó una banda de 120 pares de bases, aproximadamente, correspondiente al tamaño esperado de la fracción del minicírculo. La técnica de PCR fue el único método que detectó la presencia del parásito. Estos resultados demostraron que la sensibilidad de la PCR acelera los procesos de incriminación vectorial de las especies vectoras de leishmaniasis.

Introducing Human Population Biology through an Easy Laboratory Exercise on Mitochondrial DNA

Science.gov (United States)

Pardinas, Antonio F.; Dopico, Eduardo; Roca, Agustin; Garcia-Vazquez, Eva; Lopez, Belen

2010-01-01

This article describes an easy and cheap laboratory exercise for students to discover their own mitochondrial haplogroup. Students use buccal swabs to obtain mucosa cells as noninvasive tissue samples, extract DNA, and with a simple polymerase chain reaction-restriction fragment length polymorphism analysis they can obtain DNA fragments of…

Occurrence of Lutzomyia longipalpis andhuman and canine cases of visceral leishmaniasis and evaluation of their expansion in the Northwest region of the State of São Paulo, Brazil

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Agda Maria Oliveira

2016-02-01

Full Text Available Abstract: INTRODUCTION This paper aims to describe the dispersion of Lutzomyia longipalpis and the autochthonous occurrence of visceral leishmaniasis (VL in the Northwest region of the State of São Paulo between 2007 and 2013 and to analyze their expansion. METHODS Information about the vector and associated cases was described using maps. The incidence, mortality, and lethality of human visceral leishmaniasis (HVL were calculated. In municipalities in which more than one HVL case occurred, incidences were calculated according to census sector, and spatial and spatiotemporal clusters were identified. RESULTS The first case of HVL was reported in the municipality of Jales in 2007. By 2013, the vector and the disease had expanded from west to east, with the vector being detected in 29 municipalities. A total of 11 municipalities had cases of canine visceral leishmaniasis (CVL, and six had cases of HVL. Vector expansion occurred by vicinity with previously infested municipalities, and the expansion of VL was related to the major highways and the capital municipalities of the micro-regions in the study area. The highest incidence of HVL occurred in children between 0-4 years old, and the highest mortality and lethality occurred among persons aged 60 and older. The occurrence of HLV was more intense in the peripheral areas of municipalities with the disease. CONCLUSIONS The findings of this study may be useful for improving VL surveillance and control activities by slowing VL expansion and/or mitigating VL effects when they occur.

Genetic variation of male reproductive success in a laboratory population of Anopheles gambiae

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Voordouw Maarten J

2007-07-01

Full Text Available Abstract Background For Anopheline mosquitoes, the vectors of human malaria, genetic variation in male reproductive success can have important consequences for any control strategy based on the release of transgenic or sterile males. Methods A quantitative genetics approach was used to test whether there was a genetic component to variation in male reproductive success in a laboratory population of Anopheles gambiae. Swarms of full sibling brothers were mated with a fixed number of females and their reproductive success was measured as (1 proportion of ovipositing females, (2 proportion of ovipositing females that produced larvae, (3 proportion of females that produced larvae, (4 number of eggs laid per female, (5 number of larvae per ovipositing female and (6 number of larvae per female. Results The proportion of ovipositing females (trait 1 and the proportion of ovipositing females that produced larvae (trait 2 differed among full sib families, suggesting a genetic basis of mating success. In contrast, the other measures of male reproductive success showed little variation due to the full sib families, as their variation are probably mostly due to differences among females. While age at emergence and wing length of the males were also heritable, they were not associated with reproductive success. Larger females produced more eggs, but males did not prefer such partners. Conclusion The first study to quantify genetic variation for male reproductive success in A. gambiae found that while the initial stages of male reproduction (i.e. the proportion of ovipositing females and the proportion of ovipositing females that produced larvae had a genetic basis, the overall reproductive success (i.e. the mean number of larvae per female did not.

Laboratory automation: trajectory, technology, and tactics.

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Markin, R S; Whalen, S A

2000-05-01

Laboratory automation is in its infancy, following a path parallel to the development of laboratory information systems in the late 1970s and early 1980s. Changes on the horizon in healthcare and clinical laboratory service that affect the delivery of laboratory results include the increasing age of the population in North America, the implementation of the Balanced Budget Act (1997), and the creation of disease management companies. Major technology drivers include outcomes optimization and phenotypically targeted drugs. Constant cost pressures in the clinical laboratory have forced diagnostic manufacturers into less than optimal profitability states. Laboratory automation can be a tool for the improvement of laboratory services and may decrease costs. The key to improvement of laboratory services is implementation of the correct automation technology. The design of this technology should be driven by required functionality. Automation design issues should be centered on the understanding of the laboratory and its relationship to healthcare delivery and the business and operational processes in the clinical laboratory. Automation design philosophy has evolved from a hardware-based approach to a software-based approach. Process control software to support repeat testing, reflex testing, and transportation management, and overall computer-integrated manufacturing approaches to laboratory automation implementation are rapidly expanding areas. It is clear that hardware and software are functionally interdependent and that the interface between the laboratory automation system and the laboratory information system is a key component. The cost-effectiveness of automation solutions suggested by vendors, however, has been difficult to evaluate because the number of automation installations are few and the precision with which operational data have been collected to determine payback is suboptimal. The trend in automation has moved from total laboratory automation to a

Lutzomyia migonei is a permissive vector competent for Leishmania infantum.

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Guimarães, Vanessa Cristina Fitipaldi Veloso; Pruzinova, Katerina; Sadlova, Jovana; Volfova, Vera; Myskova, Jitka; Filho, Sinval Pinto Brandão; Volf, Petr

2016-03-17

Leishmania infantum is the most widespread etiological agent of visceral leishmaniasis (VL) in the world, with significant mortality rates in human cases. In Latin America, this parasite is primarily transmitted by Lutzomyia longipalpis, but the role of Lutzomyia migonei as a potential vector for this protozoan has been discussed. Laboratory and field investigations have contributed to this hypothesis; however, proof of the vector competence of L. migonei has not yet been provided. In this study, we evaluate for the first time the susceptibility of L. migonei to L. infantum. Females of laboratory-reared L. migonei were fed through a chick-skin membrane on rabbit blood containing L. infantum promastigotes, dissected at 1, 5 and 8 days post-infection (PI) and checked microscopically for the presence, intensity and localisation of Leishmania infections. In addition, morphometric analysis of L. infantum promastigotes was performed. High infection rates of both L. infantum strains tested were observed in L. migonei, with colonisation of the stomodeal valve already on day 5 PI. At the late-stage infection, most L. migonei females had their cardia and stomodeal valve colonised by high numbers of parasites, and no significant differences were found compared to the development in L. longipalpis. Metacyclic forms were found in all parasite-vector combinations since day 5 PI. We propose that Lutzomyia migonei belongs to sand fly species permissive to various Leishmania spp. Here we demonstrate that L. migonei is highly susceptible to the development of L. infantum. This, together with its known anthropophily, abundance in VL foci and natural infection by L. infantum, constitute important evidence that L. migonei is another vector of this parasite in Latin America.

Investigating Coccolithophorid Biology in the Sedimentary Laboratory

Science.gov (United States)

McClelland, H. L. O.; Barbarin, N.; Beaufort, L.; Hermoso, M.; Rickaby, R. E. M.

2014-12-01

Coccolithophores are the ocean's dominant calcifying phytoplankton; they play an important, but poorly understood, role in long-term biogeochemical climatic feedbacks. Calcite producing marine organisms are likely to calcify less in a future world where higher carbon dioxide concentrations will lead to ocean acidification (OA), but coccolithophores may be the exception. In coccolithophores calcification occurs in an intracellular vesicle, where the site of calcite precipitation is buffered from the external environment and is subject to a uniquely high degree of biological control. Culture manipulation experiments mimicking the effects of OA in the laboratory have yielded empirical evidence for phenotypic plasticity, competition and evolutionary adaptation in asexual populations. However, the extent to which these results are representative of natural populations, and of the response over timescales of greater than a few hundred generations, is unclear. Here we describe a new sediment-based proxy for the PIC:POC (particulate inorganic to particulate organic carbon ratio) of coccolithophore biomass, which is equivalent to the fractional energy contribution to calcification at constant pH, and a biologically meaningful measure of the organism's tendency to calcify. Employing the geological record as a laboratory, we apply this proxy to sedimentary material from the southern Pacific Ocean to investigate the integrated response of real ancient coccolithophore populations to environmental change over many thousands of years. Our results provide a new perspective on phenotypic change in real populations of coccolithophorid algae over long timescales.

1992 Environmental monitoring report, Sandia National Laboratories, Albuquerque, New Mexico

International Nuclear Information System (INIS)

Culp, T.; Cox, W.; Hwang, H.; Irwin, M.; Jones, A.; Matz, B.; Molley, K.; Rhodes, W.; Stermer, D.; Wolff, T.

1993-09-01

This 1992 report contains monitoring data from routine radiological and nonradiological environmental surveillance activities. summaries of significant environmental compliance programs in progress, such as National Environmental Policy Act documentation, environmental permits, envirorunental restoration, and various waste management programs for Sandia National Laboratories in Albuquerque, New Mexico, are included. The maximum offsite dose impact was calculated to be 0.0034 millirem. The total population within a 50-mile radius of Sandia National Laboratories/New Mexico received an estimated collective dose of 0.019 person-rem during 1992 from the laboratories' operations. As in the previous year, the 1992 operations at Sandia National Laboratories/New Mexico had no discernible impact on the general public or on the environment

[Controversies regarding distribution, instrumentation, and competence of hemodynamics laboratories].

Science.gov (United States)

Olivari, Z; Piccolo, E

2001-01-01

In the last few years we have witnessed a substantial growth in the number of catheterization laboratories, especially in the northern regions of Italy, a phenomenon which has met some controversy and has been discussed in a Symposium at the ANMCO National Conference (Florence, May 20-23, 2000). The controversy is essentially between those who believe in the implementation of catheterization laboratories in all cardiology units equipped with a cardiological intensive care unit (and the creation of a functional network with the tutorial centers) and those who refer to the existing guidelines, standards and VRQ which envisage a geographical distribution of laboratories on the basis of a balance between needs of the population and the minimum quantity of procedures performed by each center in order to guarantee the best quality and cost-effectiveness. The aim of the Symposium was to clarify whether the two "innovations" of these last few years, namely the introduction of new portable radiological equipment on the one hand and the effectiveness of primary angioplasty in the treatment of acute myocardial infarction on the other, may influence the redefinition of criteria regarding the distribution of laboratories, taking into account as well the expansion of indications for coronary angioplasty and coronary angiography. After a lively discussion, the proceedings can be summed up as follows: no agreement was reached regarding the role of portable radiological equipment in the decisional process regarding the setting up of a new catheterization laboratory; primary angioplasty should be carried out in centers with an adequate volume of activity and a functioning inter-hospital organizational structure for this demanding activity; otherwise it does not offer any advantages over fibrinolytic therapy; the proposal of a new organizational model is based on the creation of transverse inter-hospital cardiology departments, the size of which is based on the overall size of the

Heritable oxidative phosphorylation differences in a pollutant resistant Fundulus heteroclitus population

International Nuclear Information System (INIS)

Du, Xiao; Crawford, Douglas L.; Nacci, Diane E.; Oleksiak, Marjorie F.

2016-01-01

Highlights: • Laboratory reared fish from a highly polluted and clean reference population were compared. • Oxidative phosphorylation (e.g., State 3, enzymes, and proton LEAK) was quantified. • Laboratory reared F3 fish from polluted population displayed higher routine metabolism and complex II activity but lower complex I enzyme activity. • Enhanced OxPhos metabolism and toxicity resistance were retained in laboratory reared F3 fish from the polluted population. - Abstract: Populations can adapt to stress including recent anthropogenic pollution. Our published data suggests heritable differences in hepatocyte oxidative phosphorylation (OxPhos) metabolism in field-caught killifish (Fundulus heteroclitus) from the highly polluted Elizabeth River, VA, USA, relative to fish from a nearby, relatively unpolluted reference site in King’s Creek VA. Consistent with other studies showing that Elizabeth River killifish are resistant to some of the toxic effects of certain contaminants, OxPhos measurements in hepatocytes from field-caught King’s Creek but not field-caught Elizabeth River killifish were altered by acute benzo [a] pyrene exposures. To more definitively test whether the enhanced OxPhos metabolism and toxicity resistance are heritable, we measured OxPhos metabolism in a laboratory-reared F3 generation from the Elizabeth River population versus a laboratory-reared F1 generation from the King’s Creek population and compared these results to previous data from the field-caught fish. The F3 Elizabeth River fish compared to F1 King’s Creek fish had significantly higher State 3 respiration (routine metabolism) and complex II activity, and significantly lower complex I activity. The consistently higher routine metabolism in the F3 and field-caught Elizabeth River fish versus F1 and field-caught King’s Creek fish implies a heritable change in OxPhos function. The observation that LEAK, E-State, Complex I and Complex II were different in laboratory bred

Heritable oxidative phosphorylation differences in a pollutant resistant Fundulus heteroclitus population

Energy Technology Data Exchange (ETDEWEB)

Du, Xiao, E-mail: xdu@rsmas.miami.edu [Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149 (United States); Crawford, Douglas L. [Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149 (United States); Nacci, Diane E. [Population Ecology Branch, Atlantic Ecology Division, Office of Research and Development, U.S. Environmental Protection Agency, 27 Tarzwell Dr., Narragansett, RI 02882 (United States); Oleksiak, Marjorie F., E-mail: moleksiak@rsmas.miami.edu [Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149 (United States)

2016-08-15

Highlights: • Laboratory reared fish from a highly polluted and clean reference population were compared. • Oxidative phosphorylation (e.g., State 3, enzymes, and proton LEAK) was quantified. • Laboratory reared F3 fish from polluted population displayed higher routine metabolism and complex II activity but lower complex I enzyme activity. • Enhanced OxPhos metabolism and toxicity resistance were retained in laboratory reared F3 fish from the polluted population. - Abstract: Populations can adapt to stress including recent anthropogenic pollution. Our published data suggests heritable differences in hepatocyte oxidative phosphorylation (OxPhos) metabolism in field-caught killifish (Fundulus heteroclitus) from the highly polluted Elizabeth River, VA, USA, relative to fish from a nearby, relatively unpolluted reference site in King’s Creek VA. Consistent with other studies showing that Elizabeth River killifish are resistant to some of the toxic effects of certain contaminants, OxPhos measurements in hepatocytes from field-caught King’s Creek but not field-caught Elizabeth River killifish were altered by acute benzo [a] pyrene exposures. To more definitively test whether the enhanced OxPhos metabolism and toxicity resistance are heritable, we measured OxPhos metabolism in a laboratory-reared F3 generation from the Elizabeth River population versus a laboratory-reared F1 generation from the King’s Creek population and compared these results to previous data from the field-caught fish. The F3 Elizabeth River fish compared to F1 King’s Creek fish had significantly higher State 3 respiration (routine metabolism) and complex II activity, and significantly lower complex I activity. The consistently higher routine metabolism in the F3 and field-caught Elizabeth River fish versus F1 and field-caught King’s Creek fish implies a heritable change in OxPhos function. The observation that LEAK, E-State, Complex I and Complex II were different in laboratory bred

Mining of hospital laboratory information systems: a model study defining age- and gender-specific reference intervals and trajectories for plasma creatinine in a pediatric population.

Science.gov (United States)

Søeby, Karen; Jensen, Peter Bjødstrup; Werge, Thomas; Sørensen, Steen

2015-09-01

The knowledge of physiological fluctuation and variation of even commonly used biochemical quantities in extreme age groups and during development is sparse. This challenges the clinical interpretation and utility of laboratory tests in these age groups. To explore the utility of hospital laboratory data as a source of information, we analyzed enzymatic plasma creatinine as a model analyte in two large pediatric hospital samples. Plasma creatinine measurements from 9700 children aged 0-18 years were obtained from hospital laboratory databases and partitioned into high-resolution gender- and age-groups. Normal probability plots were used to deduce parameters of the normal distributions from healthy creatinine values in the mixed hospital datasets. Furthermore, temporal trajectories were generated from repeated measurements to examine developmental patterns in periods of changing creatinine levels. Creatinine shows great age dependence from birth throughout childhood. We computed and replicated 95% reference intervals in narrow gender and age bins and showed them to be comparable to those determined in healthy population studies. We identified pronounced transitions in creatinine levels at different time points after birth and around the early teens, which challenges the establishment and usefulness of reference intervals in those age groups. The study documents that hospital laboratory data may inform on the developmental aspects of creatinine, on periods with pronounced heterogeneity and valid reference intervals. Furthermore, part of the heterogeneity in creatinine distribution is likely due to differences in biological and chronological age of children and should be considered when using age-specific reference intervals.

Adaptation dynamics of laboratory populations of Drosophila Melanogaster to low dose chronic ionizing irradiation

International Nuclear Information System (INIS)

Zajnullin, V.G.; Yushkova, E.A.

2008-01-01

In genetically non-uniform populations D. melanogaster in conditions of a chronic irradiation in a doze 10-11 about sGy/generation dynamics parameters of populations was investigated. It is established, that number of individuals in irradiated populations is lower, than in control. It is revealed, that viability of populations undergone to a chronic irradiation depends on their genotype. The gradual increase in fruitfulness, viability of individuals and decrease in a level of lethal mutations in a number of generations after of an irradiation in low doses is caused by adaptable opportunities of populations. (authors)

Copulatory courtship song in Lutzomyia migonei (Diptera: psychodidae).

Science.gov (United States)

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

2010-12-01

Lutzomyia migonei is a vector of leishmaniasis with a wide distribution in South America, which could favour population differentiation and speciation. Cryptic species of the Lutzomyia longipalpis complex, the widely distributed sand fly vector of visceral leishmaniasis in Latin America, have previously been shown to display distinct copulation songs. We found that Lu. migonei males also produce a song during copulation. This "lovesong" presents short trains (6-8 pulses) with an inter-pulse interval around 26 ms and is potentially involved in cryptic female choice and insemination success.

Are laboratory derived toxicity results informative for field situations? Case study on earthworm populations contaminated with heavy metals

NARCIS (Netherlands)

Klok, T.C.; Thissen, J.

2009-01-01

The relevance of laboratory tests on toxicants for field situations is often disputed given that laboratory tests are conducted under, next to the toxicant stress, optimal conditions which are not expected in field situations. In this paper we confront the results of laboratory tests on growth,

Inoculação experimental de Equus asinus com Leishmania chagasi Cunha & Chagas, 1937 Experimental infection of Equus asinus with Leishmania chagasi Cunha & Chagas, 1937

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Elúzio José Lima Cerqueira

2003-12-01

Full Text Available Quatro Equus asinus foram inoculados com promastigotas de Leishmania chagasi Cunha & Chagas, 1937 e acompanhados durante 12 meses através de: pesquisa de amastigotas em esfregaços e culturas de sangue periférico em fragmentos de tecido do lábio inferior, medula óssea, baço e fígado e de testes de ELISA e TRALd. Estes foram positivos nos 8º, 10º e 12º meses após a inoculação. O exame histopatológico pós necropsia, demonstrou discreto número de amastigotas no fígado de dois dos eqüídeos inoculados. Apesar de desafiados com elevado número de promastigotas, os animais não desenvolveram infecções patentes e não infectaram experimentalmente a vetora Lutzomya longipalpis. Os resultados induzem a acreditar que os eqüídeos são desprovidos de importância como reservatórios na cadeia de transmissão da leishmaniose visceral, embora sirvam como boa fonte de alimentação sangüínea e proliferação da vetora Lutzomyia longipalpis.Four Equus asinus were challenged with promastigotes of Leishmania chagasi Cunha & Chagas, 1937, and followed up for 12 months. They were observed by means of direct testing for promastigotes in smears and culture of peripheral blood, fragments from inferior lip, bone marrow, spleen and liver and the immunological assays ELISA and TRALd. The post-necropsy histological examination demonstrated a small number of amastigotes in the liver of two animals. ELISA and TRALd tests were positive at the 8th, 10th and 12th month after inoculation. The results suggest that the donkeys were able to overcome the experimental leishmanial infection and did not infect the vector Lutzomyia longipalpis in the laboratory. Consequently they can not be considered an important reservoir in the epidemiological chain of transmission of visceral leishmaniasis, although they represent an important blood source for the vector and its proliferation.

Effectiveness of influenza vaccine against laboratory-confirmed influenza, in the late 2011–2012 season in Spain, among population targeted for vaccination

Science.gov (United States)

2013-01-01

Background In Spain, the influenza vaccine effectiveness (VE) was estimated in the last three seasons using the observational study cycEVA conducted in the frame of the existing Spanish Influenza Sentinel Surveillance System. The objective of the study was to estimate influenza vaccine effectiveness (VE) against medically attended, laboratory-confirmed influenza-like illness (ILI) among the target groups for vaccination in Spain in the 2011–2012 season. We also studied influenza VE in the early (weeks 52/2011-7/2012) and late (weeks 8-14/2012) phases of the epidemic and according to time since vaccination. Methods Medically attended patients with ILI were systematically swabbed to collect information on exposure, laboratory outcome and confounding factors. Patients belonging to target groups for vaccination and who were swabbed 4 months, respectively, since vaccination. A decrease in VE with time since vaccination was only observed in individuals aged ≥ 65 years. Regarding the phase of the season, decreasing point estimates were only observed in the early phase, whereas very low or null estimates were obtained in the late phase for the shortest time interval. Conclusions The 2011–2012 influenza vaccine showed a low-to-moderate protective effect against medically attended, laboratory-confirmed influenza in the target groups for vaccination, in a late season and with a limited match between the vaccine and circulating strains. The suggested decrease in influenza VE with time since vaccination was mostly observed in the elderly population. The decreasing protective effect of the vaccine in the late part of the season could be related to waning vaccine protection because no viral changes were identified throughout the season. PMID:24053661

Laboratory diagnostic methods, system of quality and validation

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Ašanin Ružica

2005-01-01

Full Text Available It is known that laboratory investigations secure safe and reliable results that provide a final confirmation of the quality of work. Ideas, planning, knowledge, skills, experience, and environment, along with good laboratory practice, quality control and reliability of quality, make the area of biological investigations very complex. In recent years, quality control, including the control of work in the laboratory, is based on international standards and is used at that level. The implementation of widely recognized international standards, such as the International Standard ISO/IEC 17025 (1 and the implementing of the quality system series ISO/IEC 9000 (2 have become the imperative on the grounds of which laboratories have a formal, visible and corresponding system of quality. The diagnostic methods that are used must constantly yield results which identify the animal as positive or negative, and the precise status of the animal is determined with a predefined degree of statistical significance. Methods applied on a selected population reduce the risk of obtaining falsely positive or falsely negative results. A condition for this are well conceived and documented methods, with the application of the corresponding reagents, and work with professional and skilled staff. This process requires also a consistent implementation of the most rigorous experimental plans, epidemiological and statistical data and estimations, with constant monitoring of the validity of the applied methods. Such an approach is necessary in order to cut down the number of misconceptions and accidental mistakes, for a referent population of animals on which the validity of a method is tested. Once a valid method is included in daily routine investigations, it is necessary to apply constant monitoring for the purpose of internal quality control, in order adequately to evaluate its reproducibility and reliability. Consequently, it is necessary at least twice yearly to conduct

Adaptation of natural drosophila populations from radiocontaminated areas of Belarus

International Nuclear Information System (INIS)

Mosseh, I.B.; Glushkova, I.V.; Anoshenko, I.P.; Aksyutik, T.V.

2005-01-01

Genetic monitoring of natural drosophila populations from the area radiation contaminated due to Chernobyl accident (Vetka district of Gomel region) and from the control area (Byarehzinski National Reserve) had been conducted. Flies from radiation contaminated area were shown to be much more adapted to irradiation than insects from the control region. Then the population samples were kept under laboratory condition without irradiation for 8 generations. Adaptation of Vetka population to irradiation remained.. Besides the control population became also more resistant to ionizing radiation. Keeping of natural populations under laboratory or vivarium conditions is a strong stress (limited space, overpopulation, other than in nature temperature and light conditions), which increases mutation process and induces unspecific adaptation. These facts should be taken into account in studying dynamics of the mutation level during radionuclide removal in animals caught in radiation contaminated regions and placed in vivarium conditions. (authors)

Recommendations concerning classification of and discharge standards for radionuclide laboratories

International Nuclear Information System (INIS)

1985-01-01

In the report recommendations are made for the limitation of the radioactive gaseous and liquid effluents from radionuclide laboratories. The recommended values are based on a radiation exposure for members of a critical group in the population corresponding to 1% of the dose limit for individual members of the public as recommended by the ICRP. Based on these standards a classification of radionuclide laboratories is proposed. It is recommended to retain the present Dutch classification in A-, B-, C- and D-laboratories. The report contains appendices with detailed data about the transport routes of radionuclides in the environment and the subsequent irradiation of members of the public. (orig.)

New Mexicans` images and perceptions of Los Alamos National Laboratory. Winter, 1992--1993

Energy Technology Data Exchange (ETDEWEB)

NONE

1993-01-01

This report uses survey data to profile New Mexico residents` images and perceptions of Los Alamos National Laboratory (LANL). The survey results are the responses of a representative, stratified random sample of 992 New Mexico households to a set of questions asked in October, 1992. The data allow statistical inference to the general population`s responses to the same set of questions at the time the survey was administered. The results provide an overview of New Mexico residents` current images and perceptions of the Laboratory. The sample margin of error is plus or minus 3.5% at the 95% confidence level.

Road Transportable Analytical Laboratory (RTAL) system

International Nuclear Information System (INIS)

Finger, S.M.

1995-01-01

U.S. Department of Energy (DOE) facilities around the country have, over the years, become contaminated with radionuclides and a range of organic and inorganic wastes. Many of the DOE sites encompass large land areas and were originally sited in relatively unpopulated regions of the country to minimize risk to surrounding populations. In addition, wastes were sometimes stored underground at the sites in 55-gallon drums, wood boxes or other containers until final disposal methods could be determined. Over the years, these containers have deteriorated, releasing contaminants into the surrounding environment. This contamination has spread, in some cases polluting extensive areas. The DOE would benefit greatly if it had reliable, road transportable, fully independent laboratory systems that could perform on-site the full range of analyses required. The goal of the Road Transportable Analytical Laboratory (RTAL) project is the development and demonstration of a system to meet the unique needs of the DOE for rapid, accurate analysis of a wide variety of hazardous and radioactive contaminants in soils, ground water and surface waters. This document describes the requirements for such a laboratory

Nationwide survey of policies and practices related to capillary blood sampling in medical laboratories in Croatia.

Science.gov (United States)

Krleza, Jasna Lenicek

2014-01-01

Capillary sampling is increasingly used to obtain blood for laboratory tests in volumes as small as necessary and as non-invasively as possible. Whether capillary blood sampling is also frequent in Croatia, and whether it is performed according to international laboratory standards is unclear. All medical laboratories that participate in the Croatian National External Quality Assessment Program (N = 204) were surveyed on-line to collect information about the laboratory's parent institution, patient population, types and frequencies of laboratory tests based on capillary blood samples, choice of reference intervals, and policies and procedures specifically related to capillary sampling. Sampling practices were compared with guidelines from the Clinical and Laboratory Standards Institute (CLSI) and the World Health Organization (WHO). Of the 204 laboratories surveyed, 174 (85%) responded with complete questionnaires. Among the 174 respondents, 155 (89%) reported that they routinely perform capillary sampling, which is carried out by laboratory staff in 118 laboratories (76%). Nearly half of respondent laboratories (48%) do not have a written protocol including order of draw for multiple sampling. A single puncture site is used to provide capillary blood for up to two samples at 43% of laboratories that occasionally or regularly perform such sampling. Most respondents (88%) never perform arterialisation prior to capillary blood sampling. Capillary blood sampling is highly prevalent in Croatia across different types of clinical facilities and patient populations. Capillary sampling procedures are not standardised in the country, and the rate of laboratory compliance with CLSI and WHO guidelines is low.

Fate of Listeria spp. on parsley leaves grown in laboratory and field cultures.

Science.gov (United States)

Dreux, N; Albagnac, C; Carlin, F; Morris, C E; Nguyen-The, C

2007-11-01

To investigate the population dynamics of Listeria monocytogenes and Listeria innocua on the aerial surfaces of parsley. Under 100% relative humidity (RH) in laboratory and regardless of the inoculum tested (10(3)-10(8) CFU per leaf), counts of L. monocytogenes EGDe, LO28, LmP60 and L. innocua CIP 80-12 tended towards approx. 10(5) CFU per leaf. Under low RH, Listeria spp. populations declined regardless to the inoculum size (10(4)-10(8) CFU per leaf). L. innocua CIP 80-12 survived slightly better than L. monocytogenes in the laboratory and was used in field cultures. Under field cultures, counts of L. innocua decreased more rapidly than in the laboratory, representing a decrease of 9 log(10) in 2 days in field conditions compared to a decrease of 4.5 log(10) in 8 days in the laboratory. Counts of L. innocua on tunnel parsley cultures were always higher (at least by 100 times) than those on unprotected parsley culture. Even with a high inoculum and under protected conditions (i.e. plastic tunnels), population of L. monocytogenes on the surface of parsley on the field would decrease by several log(10) scales within 2 days. Direct contamination of aerial surfaces of parsley with L. monocytogenes (i.e. through contaminated irrigation water) will not lead to contaminated produce unless it occurs very shortly before harvest.

Thomas Pettersson: Towards a more welcoming laboratory

CERN Multimedia

2009-01-01

The General Services (GS) Department is a brand new department whose mission is to consolidate the infrastructure of CERN as a global laboratory. With an expected increase of 50% in the number of users in the next five years (bringing it to about 15 000!), this is far from an easy task. The LHC is a challenge not only from the point of view of the technical equipment and the scientific issues it will address; it represents a big challenge for the infrastructure of CERN as a whole, its buildings, offices, roads, hostels, services, etc. The Laboratory expects its population of users to grow from the present 10 000 members to 15 000 in about five years with no significant increase in staff. This will demand all sorts of initiatives that the Laboratory will have to undertake in order to keep and improve the level of services that it provides to the community. The new GS Department has been created to respond to this and other challenges...

Laboratory Medicine is Faced with the Evolution of Medical Practice

Directory of Open Access Journals (Sweden)

Collinson Paul

2017-09-01

Full Text Available Laboratory medicine and clinical medicine are co-dependent components of medicine. Laboratory medicine functions most effectively when focused through a clinical lens. Me dical practice as a whole undergoes change. New drugs, treatments and changes in management strategies are introduced. New techniques, new technologies and new tests are developed. These changes may be either clinically or laboratory initiated, and so their introduction requires dialogue and interaction between clinical and laboratory medicine specialists. Treatment monitoring is integral to laboratory medicine, varying from direct drug measurement to monitoring cholesterol levels in response to treatment. The current trend to »personalised medicine« is an extension of this process with the development of companion diagnostics. Technological innovation forms part of modern laboratory practice. Introduction of new technology both facilitates standard laboratory approaches and permits introduction of new tests and testing strategies previously confined to the research laboratory only. The revolution in cardiac biomarker testing has been largely a laboratory led change. Flexibility in service provision in response to changing clinical practice or evolving technology provides a significant laboratory management challenge in the light of increasing expectations, shifts in population demographics and constraint in resource availability. Laboratory medicine practitioners are adept at meeting these challenges. One thing remains constant, that there will be a constant need laboratory medicine to meet the challenges of novel clinical challenges from infectious diseases to medical conditions developing from lifestyle and longevity.

Trends in leprosy case detection in Rwanda, 1995–2011: analysis of 17 years of laboratory data

Directory of Open Access Journals (Sweden)

Innocent Uwimana

2017-02-01

Objective: We analysed laboratory records to assess trends in prevalence rates and case detection rates (CDRs in Rwanda. Methods: A retrospective review of detected leprosy cases from the records of the Rwanda National Reference Laboratory over a 17-year period (1995–2011 was conducted. Skin biopsy samples were analysed microscopically using Ziehl-Neelsen staining technique to identify M. leprae. Results: Cumulatively, 266 suspected cases were reported between 1995 and 2011. Of the suspected cases, 77 (28.9% were laboratory confirmed as having leprosy. Among detected cases, 59 (76.6% were men and 18 (23.4% women. The male:female ratio was 3:1. There were 77 registered leprosy cases over the 17-year period of the study, and the prevalence rate was 0.005 per 10 000 population. A gradual decrease in the prevalence rate was observed from 0.015 per 10 000 population in 2003 to 0.003 per 10 000 population in 2010. From 1995 to 2011, the CDR did not exceed one per 10 000 population. Conclusion: This laboratory review demonstrates a declining trend in prevalence rates and CDR during the period of the study. Early case detection and a sustainable leprosy control programme remain the cornerstones of reducing the physical and socio-economic burden of leprosy in Rwanda.

Laboratory of environmental radiological surveillance

International Nuclear Information System (INIS)

Mendez G, A.; Marcial M, F.; Giber F, J.; Montiel R, E.; Leon del V, E.; Rivas C, I.; Leon G, M.V.; Lagunas G, E.; Aragon S, R.; Juarez N, A.; Alfaro L, M.M.

1991-12-01

The department of radiological protection of the ININ requests the collaboration of the Engineering Unit for the elaboration of the work project of the laboratory of environmental radiological surveillance. The emission of radioactive substances to the atmosphere like consequence of the normal operation of the Nuclear Center, constitutes an exhibition source from the man to the radiations that it should be appropriately watched over and controlled to be able to determine the population's potential exhibition that it lives in the area of influence of the installation. (Author)

1994 Site Environmental Report Sandia National Laboratories Albuquerque, New Mexico

International Nuclear Information System (INIS)

Shyr, L.J.; Wiggins, T.; White, B.B.

1995-09-01

This 1994 report contains data from routine radiological and nonradiological environmental monitoring activities. Summaries of significant environmental compliance programs in progress, such as National Environmental Policy Act documentation, environmental permits, environmental restoration, and various waste management programs for Sandia National Laboratories in Albuquerque, New Mexico, are included. The maximum off-site dose impact from air emissions was calculated to be 1.5 x 10 -4 millirem. The total population within a 50-mile radius of Sandia National Laboratories/New Mexico received an estimated collective dose of 0.012 person-rem during 1994 from the laboratories' operations. This report is prepared for the U.S. Department of Energy in compliance with DOE Order 5400.1

Lunar-Rhythmic Molting in Laboratory Populations of the Noble Crayfish Astacus astacus (Crustacea, Astacidea): An Experimental Analysis

Science.gov (United States)

Franke, Robert; Hoerstgen-Schwark, Gabriele

2013-01-01

Juvenile noble crayfish, Astacusastacus (Crustacea, Astacidea) in the second year of age were kept in the laboratory for a twelve-month period under continuing “summer conditions” (LD 16:8, 19°C). Molting processes in this population could be synchronized by artificial moonlight cycles. Peaks of exuviations occurred at “new moons”. Males showed a slightly higher degree of synchronization than females. A phase-shift of the artificial lunar cycle in relation to the natural cycle resulted in a corresponding shift of the molting cycle. This clearly demonstrates that changes in the nocturnal light regime provide the primary external information for the lunar-monthly molting rhythm. There is a first indication that lunar photic stimuli do not act directly but as a zeitgeber which entrains an endogenous molting rhythm to the lunar cycle. Moreover, the results of the long-term experiments suggest that the hibernal resting period of A . astacus in the field (no molts between October and April) may also involve some endogenous programming. Continuing artificial summer conditions can delay but not completely suppress this resting period. The adaptive significance of the phenomena and how the findings may be applied to improve the management of crowded crayfish stocks are discussed. PMID:23840899

1993 Site environmental report Sandia National Laboratories, Albuquerque, New Mexico

International Nuclear Information System (INIS)

Culp, T.A.; Cheng, C.F.; Cox, W.; Durand, N.; Irwin, M.; Jones, A.; Lauffer, F.; Lincoln, M.; McClellan, Y.; Molley, K.

1994-11-01

This 1993 report contains monitoring data from routine radiological and nonradiological environmental surveillance activities. Summaries of significant environmental compliance programs in progress, such as National Environmental Policy Act documentation, environmental permits, environmental restoration, and various waste management programs for Sandia National Laboratories in Albuquerque, New Mexico, are included. The maximum offsite dose impact was calculated to be 0.0016 millirem. The total population within a 50-mile (80 kilometer) radius of Sandia National Laboratories/New Mexico received an estimated collective dose of 0.027 person-rem during 1993 from the laboratories operations, As in the previous year, the 1993 operations at Sandia National Laboratories/New Mexico had no discernible impact on the general public or on the environment. This report is prepared for the U.S. Department of Energy in compliance with DOE Order 5400.1

Insecticide resistance and cytochrome-P450 activation in unfed and blood-fed laboratory and field populations of Culex pipiens pallens.

Science.gov (United States)

Chang, Kyu-Sik; Kim, Heung-Chul; Klein, Terry A; Ju, Young Ran

2017-01-01

Understanding the mechanisms of insecticide resistance to vector mosquitoes is critical for the implementation of effective control measures. A nulliparous susceptible Culex pipiens pallens (KSCP) laboratory colony and two field strains from Paju (PAJ) and Jeonju (JEO) Korea were evaluated for susceptibility to five pesticides by microapplication techniques. Unfed PAJ and JEO females demonstrated increased resistance compared to unfed KSCP females, respectively. While blood-fed KSCP females demonstrated resistance compared to unfed PAJ and JEO females, respectively. Unfed and blood-fed groups were assayed for α- and β-esterase, glutathione S -transferases, and cytochrome P-450 (P450) enzyme activity assays. P450 activity was 58.8- and 72.8-fold higher for unfed PAJ and JEO females, respectively, than unfed KSCP females. P450 enzyme activity of KSCP females assayed 1 and 7 days after a blood meal increased by 14.5- and 11.8-fold, respectively, compared to unfed KSCP females, while PAJ and JEO females demonstrated 164.9- and 148.5- and 170.7- and 160.4-fold increased activity, respectively, compared to unfed females of each population. However, other three resistance-related metabolic enzymes showed low activation at P450 acts on elevated insecticide resistance after blood meals in resistant field populations. Our findings might reveal that suppressing of the P450 protein by artificial gene mutation increases insecticidal susceptibility of Cx . pipiens and will promise effective vector mosquito control.

Cancer and workers' compensation at Chalk River nuclear laboratories

International Nuclear Information System (INIS)

Evans, D.W.S.

1985-01-01

This paper describes the circumstances leading to the notification to the Worker's Compensation Board of Ontario of two cases of cancer, both involving the lymphatic and haematoporetic systems, in employees at Chalk River Nulcear Laboratories. Twenty of these neoplasms are known to have occurred in the CRNL population between 1966 and 1983. The leukemia/lymphoma ratio observed in the twenty neoplasms is similar to that found in populations not occupationally exposed to ionizing radiation. The possible relationship between asbestos exposure and lymphoid neoplasms was discussed. 5 refs

Designation, diligence and drift: understanding laboratory expenditure increases in British Columbia, 1996/97 to 2005/06.

Science.gov (United States)

Sivananthan, Saskia N; Peterson, Sandra; Lavergne, Ruth; Barer, Morris L; McGrail, Kimberlyn M

2012-12-21

Laboratory testing is one of the fastest growing areas of health services spending in Canada. We examine the extent to which increases in laboratory expenditures might be explained by testing that is consistent with guidelines for the management of chronic conditions, by analyzing fee-for-service physician payment data in British Columbia from 1996/97 and 2005/06. We used direct standardization to quantify the effect on laboratory expenditures from changes in: fee levels; population growth; population aging; treatment prevalence; expenditure on recommended tests for those conditions; and expenditure on other tests. The chronic conditions selected were those with guidelines containing laboratory recommendations developed by the BC Guidelines and Protocol Advisory Committee: diabetes, hypertension, congestive heart failure, renal failure, liver disease, rheumatoid arthritis, osteoarthritis and dementia. Laboratory service expenditures increased by $98 million in 2005/06 compared to 1996/97, or 3.6% per year after controlling for population growth and aging. Testing consistent with guideline-recommended care for chronic conditions explained one-third (1.2% per year) of this growth. Changes in treatment prevalence were just as important, contributing 1.5% per year. Hypertension was the most common condition, but renal failure and dementia showed the largest changes in prevalence over time. Changes in other laboratory expenditure including for those without chronic conditions accounted for the remaining 0.9% growth per year. Increases in treatment prevalence were the largest driver of laboratory cost increases between 1996/97 and 2005/06. There are several possible contributors to increasing treatment prevalence, all of which can be expected to continue to put pressure on health care expenditures.

Annual environmental monitoring report of the Lawrence Berkeley Laboratory

International Nuclear Information System (INIS)

Schleimer, G.E.

1989-06-01

The Environmental Monitoring Program of the Lawrence Berkeley Laboratory (LBL) is described. Data for 1988 are presented and general trends are discussed. In order to establish whether LBL research activities produced any impact on the population surrounding the laboratory, a program of environmental air and water sampling and continuous radiation monitoring was carried on throughout the year. For 1988, as in the previous several years, dose equivalents attributable to LBL radiological operations were a small fraction of both the relevant radiation protection guidelines (RPG) and of the natural radiation background. 16 refs., 7 figs., 21 tabs

Annual environmental monitoring report of the Lawrence Berkeley Laboratory

Energy Technology Data Exchange (ETDEWEB)

Schleimer, G.E. (ed.)

1989-06-01

The Environmental Monitoring Program of the Lawrence Berkeley Laboratory (LBL) is described. Data for 1988 are presented and general trends are discussed. In order to establish whether LBL research activities produced any impact on the population surrounding the laboratory, a program of environmental air and water sampling and continuous radiation monitoring was carried on throughout the year. For 1988, as in the previous several years, dose equivalents attributable to LBL radiological operations were a small fraction of both the relevant radiation protection guidelines (RPG) and of the natural radiation background. 16 refs., 7 figs., 21 tabs.

Road Transportable Analytical Laboratory (RTAL) system

International Nuclear Information System (INIS)

Finger, S.M.

1995-01-01

U.S. Department of Energy (DOE) facilities around the country have, over the years, become contaminated with radionuclides and a range of organic and inorganic wastes. Many of the DOE sites encompass large land areas and were originally sited in relatively unpopulated regions of the country to minimize risk to surrounding populations. In addition, wastes were sometimes stored underground at the sites in 55-gallon drums, wood boxes or other containers until final disposal methods could be determined. Over the years, these containers have deteriorated, releasing contaminants into the surrounding environment. This contamination has spread, in some cases polluting extensive areas. Remediation of these sites requires extensive sampling to determine the extent of the contamination, to monitor clean-up and remediation progress, and for post-closure monitoring of facilities. The DOE would benefit greatly if it had reliable, road transportable, fully independent laboratory systems that could perform on-site the full range of analyses required. Such systems would accelerate and thereby reduce the cost of clean-up and remediation efforts by (1) providing critical analytical data more rapidly, and (2) eliminating the handling, shipping and manpower associated with sample shipments. The goal of the Road Transportable Analytical Laboratory (RTAL) Project is the development and demonstration of a system to meet the unique needs of the DOE for rapid, accurate analysis of a wide variety of hazardous and radioactive contaminants in soil, groundwater, and surface waters. This laboratory system has been designed to provide the field and laboratory analytical equipment necessary to detect and quantify radionuclides, organics, heavy metals and other inorganic compounds. The laboratory system consists of a set of individual laboratory modules deployable independently or as an interconnected group to meet each DOE site's specific needs

Population modelling to compare chronic external radiotoxicity between individual and population endpoints in four taxonomic groups.

Science.gov (United States)

Alonzo, Frédéric; Hertel-Aas, Turid; Real, Almudena; Lance, Emilie; Garcia-Sanchez, Laurent; Bradshaw, Clare; Vives I Batlle, Jordi; Oughton, Deborah H; Garnier-Laplace, Jacqueline

2016-02-01

In this study, we modelled population responses to chronic external gamma radiation in 12 laboratory species (including aquatic and soil invertebrates, fish and terrestrial mammals). Our aim was to compare radiosensitivity between individual and population endpoints and to examine how internationally proposed benchmarks for environmental radioprotection protected species against various risks at the population level. To do so, we used population matrix models, combining life history and chronic radiotoxicity data (derived from laboratory experiments and described in the literature and the FREDERICA database) to simulate changes in population endpoints (net reproductive rate R0, asymptotic population growth rate λ, equilibrium population size Neq) for a range of dose rates. Elasticity analyses of models showed that population responses differed depending on the affected individual endpoint (juvenile or adult survival, delay in maturity or reduction in fecundity), the considered population endpoint (R0, λ or Neq) and the life history of the studied species. Among population endpoints, net reproductive rate R0 showed the lowest EDR10 (effective dose rate inducing 10% effect) in all species, with values ranging from 26 μGy h(-1) in the mouse Mus musculus to 38,000 μGy h(-1) in the fish Oryzias latipes. For several species, EDR10 for population endpoints were lower than the lowest EDR10 for individual endpoints. Various population level risks, differing in severity for the population, were investigated. Population extinction (predicted when radiation effects caused population growth rate λ to decrease below 1, indicating that no population growth in the long term) was predicted for dose rates ranging from 2700 μGy h(-1) in fish to 12,000 μGy h(-1) in soil invertebrates. A milder risk, that population growth rate λ will be reduced by 10% of the reduction causing extinction, was predicted for dose rates ranging from 24 μGy h(-1) in mammals to 1800 μGy h(-1) in

Nationwide survey of policies and practices related to capillary blood sampling in medical laboratories in Croatia

Science.gov (United States)

Krleza, Jasna Lenicek

2014-01-01

Introduction: Capillary sampling is increasingly used to obtain blood for laboratory tests in volumes as small as necessary and as non-invasively as possible. Whether capillary blood sampling is also frequent in Croatia, and whether it is performed according to international laboratory standards is unclear. Materials and methods: All medical laboratories that participate in the Croatian National External Quality Assessment Program (N = 204) were surveyed on-line to collect information about the laboratory’s parent institution, patient population, types and frequencies of laboratory tests based on capillary blood samples, choice of reference intervals, and policies and procedures specifically related to capillary sampling. Sampling practices were compared with guidelines from the Clinical and Laboratory Standards Institute (CLSI) and the World Health Organization (WHO). Results: Of the 204 laboratories surveyed, 174 (85%) responded with complete questionnaires. Among the 174 respondents, 155 (89%) reported that they routinely perform capillary sampling, which is carried out by laboratory staff in 118 laboratories (76%). Nearly half of respondent laboratories (48%) do not have a written protocol including order of draw for multiple sampling. A single puncture site is used to provide capillary blood for up to two samples at 43% of laboratories that occasionally or regularly perform such sampling. Most respondents (88%) never perform arterialisation prior to capillary blood sampling. Conclusions: Capillary blood sampling is highly prevalent in Croatia across different types of clinical facilities and patient populations. Capillary sampling procedures are not standardised in the country, and the rate of laboratory compliance with CLSI and WHO guidelines is low. PMID:25351353

Geometric morphometric differences between Panstrongylus geniculatus from field and laboratory

Directory of Open Access Journals (Sweden)

Nicolás Jaramillo O

2002-07-01

Full Text Available The finding of Panstrongylus geniculatus nymphs inside a house in northeastern Antioquia, Colombia, and the reports related to their increasing presence in homes suggest the need for surveillance methods for monitoring the invasion processes. We analyzed the morphological differences between a wild population and its laboratory descendants, using the techniques of geometric morphometry, with the idea that such differences might parallel those between sylvatic and synanthropic populations. The analyses over five generations showed differences in size but not in shape. Head size and wing size were both reduced from sylvatic to laboratory populations, but the decrease in head size occurred only up to the second generation while the decrease in wing size proceeded up to the fifth generation. In contrast, although a decrease in sexual size dimorphism has been proposed as a marker of colonization in human dwellings, we did not detect any significant loss of dimorphism between sexes of P. geniculatus over the five generations studied. We conclude that size changes may have a physiological origin in response to a change of ecotopes, but more than five generations may be required for the expression of permanent morphological markers of human dwellings colonization.

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

Science.gov (United States)

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

2003-07-01

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

Age structure changes and extraordinary lifespan in wild medfly populations.

Science.gov (United States)

Carey, James R; Papadopoulos, Nikos T; Müller, Hans-Georg; Katsoyannos, Byron I; Kouloussis, Nikos A; Wang, Jane-Ling; Wachter, Kenneth; Yu, Wei; Liedo, Pablo

2008-06-01

The main purpose of this study was to test the hypotheses that major changes in age structure occur in wild populations of the Mediterranean fruit fly (medfly) and that a substantial fraction of individuals survive to middle age and beyond (> 3-4 weeks). We thus brought reference life tables and deconvolution models to bear on medfly mortality data gathered from a 3-year study of field-captured individuals that were monitored in the laboratory. The average time-to-death of captured females differed between sampling dates by 23.9, 22.7, and 37.0 days in the 2003, 2004, and 2005 field seasons, respectively. These shifts in average times-to-death provided evidence of changes in population age structure. Estimates indicated that middle-aged medflies (> 30 days) were common in the population. A surprise in the study was the extraordinary longevity observed in field-captured medflies. For example, 19 captured females but no reference females survived in the laboratory for 140 days or more, and 6 captured but no reference males survived in the laboratory for 170 days or more. This paper advances the study of aging in the wild by introducing a new method for estimating age structure in insect populations, demonstrating that major changes in age structure occur in field populations of insects, showing that middle-aged individuals are common in the wild, and revealing the extraordinary lifespans of wild-caught individuals due to their early life experience in the field.

Malignant melanoma among employees of Lawrence Livermore National Laboratory

International Nuclear Information System (INIS)

Austin, D.F.; Reynolds, P.J.; Snyder, M.A.; Biggs, M.W.; Stubbs, H.A.

1981-01-01

19 cases of malignant melanoma (MM) were observed during 1972-77 among approximately 5100 employees of the Lawrence Livermore National Laboratory, where high energy physics research is conducted. This number was significantly higher (p -6 ) than that expected in a comparable age/race/sex/geographical segment of the population of the San Francisco Bay area. That excess seemed to occur only among laboratory employees and not among the surrounding community, which suggests that an occupational factor is responsible. Preliminary case-comparison findings suggest that MM risk is not associated with length of employment at the laboratory nor with type of monitored radiation exposure. Although the data did not support an association between MM incidence and all scientific job classifications combined, an excess relative risk was observed among chemists. The reasons for the MM excess have not been identified. (author)

Cooperation, cheating, and collapse in biological populations

Science.gov (United States)

Gore, Jeff

2014-03-01

Natural populations can collapse suddenly in response to small changes in environmental conditions, and recovery from such a collapse can be difficult. We have used laboratory microbial ecosystems to directly measure theoretically proposed early warning signals of impending population collapse. Yeast cooperatively break down the sugar sucrose, meaning that below a critical size the population cannot sustain itself. We have demonstrated experimentally that changes in the fluctuations of the population size can serve as an early warning signal that the population is close to collapse. The cooperative nature of yeast growth on sucrose suggests that the population may be susceptible to ``cheater'' cells, which do not contribute to the public good and instead merely take advantage of the cooperative cells. We confirm this possibility experimentally and find that such social parasitism decreases the resilience of the population.

Evidence of Field-Evolved Resistance to Bifenthrin in Western Corn Rootworm (Diabrotica virgifera virgifera LeConte) Populations in Western Nebraska and Kansas.

Science.gov (United States)

Pereira, Adriano E; Wang, Haichuan; Zukoff, Sarah N; Meinke, Lance J; French, B Wade; Siegfried, Blair D

2015-01-01

Pyrethroid insecticides have been used to control larvae or adults of the western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, a key pest of field corn in the United States. In response to reports of reduced efficacy of pyrethroids in WCR management programs in southwestern areas of Nebraska and Kansas the present research was designed to establish a baseline of susceptibility to the pyrethroid insecticide, bifenthrin, using susceptible laboratory populations and to compare this baseline with susceptibility of field populations. Concentration-response bioassays were performed to estimate the baseline susceptibility. From the baseline data, a diagnostic concentration (LC99) was determined and used to test adults of both laboratory and field populations. Larval susceptibility was also tested using both laboratory and field populations. Significant differences were recorded in adult and larval susceptibility among WCR field and laboratory populations. The highest LC50 for WCR adults was observed in populations from Keith 2 and Chase Counties, NE, with LC50s of 2.2 and 1.38 μg/vial, respectively, and Finney County 1, KS, with 1.43 μg/vial, as compared to a laboratory non-diapause population (0.24 μg/vial). For larvae, significant differences between WCR field and laboratory populations were also recorded. Significant differences in mortalities at the diagnostic bifenthrin concentration (LC99) were observed among WCR adult populations with western Corn Belt populations exhibiting lower susceptibility to bifenthrin, especially in southwestern Nebraska and southwestern Kansas. This study provides evidence that resistance to bifenthrin is evolving in field populations that have been exposed for multiple years to pyrethroid insecticides. Implications to sustainable rootworm management are discussed.

Evidence of Field-Evolved Resistance to Bifenthrin in Western Corn Rootworm (Diabrotica virgifera virgifera LeConte Populations in Western Nebraska and Kansas.

Directory of Open Access Journals (Sweden)

Adriano E Pereira

Full Text Available Pyrethroid insecticides have been used to control larvae or adults of the western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte, a key pest of field corn in the United States. In response to reports of reduced efficacy of pyrethroids in WCR management programs in southwestern areas of Nebraska and Kansas the present research was designed to establish a baseline of susceptibility to the pyrethroid insecticide, bifenthrin, using susceptible laboratory populations and to compare this baseline with susceptibility of field populations. Concentration-response bioassays were performed to estimate the baseline susceptibility. From the baseline data, a diagnostic concentration (LC99 was determined and used to test adults of both laboratory and field populations. Larval susceptibility was also tested using both laboratory and field populations. Significant differences were recorded in adult and larval susceptibility among WCR field and laboratory populations. The highest LC50 for WCR adults was observed in populations from Keith 2 and Chase Counties, NE, with LC50s of 2.2 and 1.38 μg/vial, respectively, and Finney County 1, KS, with 1.43 μg/vial, as compared to a laboratory non-diapause population (0.24 μg/vial. For larvae, significant differences between WCR field and laboratory populations were also recorded. Significant differences in mortalities at the diagnostic bifenthrin concentration (LC99 were observed among WCR adult populations with western Corn Belt populations exhibiting lower susceptibility to bifenthrin, especially in southwestern Nebraska and southwestern Kansas. This study provides evidence that resistance to bifenthrin is evolving in field populations that have been exposed for multiple years to pyrethroid insecticides. Implications to sustainable rootworm management are discussed.

Draft environmental assessment of Argonne National Laboratory, East

Energy Technology Data Exchange (ETDEWEB)

1975-10-01

This environmental assessment of the operation of the Argonne National Laboratory is related to continuation of research and development work being conducted at the Laboratory site at Argonne, Illinois. The Laboratory has been monitoring various environmental parameters both offsite and onsite since 1949. Meteorological data have been collected to support development of models for atmospheric dispersion of radioactive and other pollutants. Gaseous and liquid effluents, both radioactive and non-radioactive, have been measured by portable monitors and by continuous monitors at fixed sites. Monitoring of constituents of the terrestrial ecosystem provides a basis for identifying changes should they occur in this regime. The Laboratory has established a position of leadership in monitoring methodologies and their application. Offsite impacts of nonradiological accidents are primarily those associated with the release of chlorine and with sodium fires. Both result in releases that cause no health damage offsite. Radioactive materials released to the environment result in a cumulative dose to persons residing within 50 miles of the site of about 47 man-rem per year, compared to an annual total of about 950,000 man-rem delivered to the same population from natural background radiation. 100 refs., 17 figs., 33 tabs.

Data sharing report characterization of population 7: Personal protective equipment, dry active waste, and miscellaneous debris, surveillance and maintenance project Oak Ridge National Laboratory Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

Harpenau, Evan M. [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States)

2013-10-10

The U.S. Department of Energy (DOE) Oak Ridge Office of Environmental Management (EM-OR) requested that Oak Ridge Associated Universities (ORAU), working under the Oak Ridge Institute for Science and Education (ORISE) contract, provide technical and independent waste management planning support under the American Recovery and Reinvestment Act (ARRA). Specifically, DOE EM-OR requested that ORAU plan and implement a sampling and analysis campaign targeting certain URS|CH2M Oak Ridge, LLC (UCOR) surveillance and maintenance (S&M) process inventory waste. Eight populations of historical and reoccurring S&M waste at the Oak Ridge National Laboratory (ORNL) have been identified in the Waste Handling Plan for Surveillance and Maintenance Activities at the Oak Ridge National Laboratory, DOE/OR/01-2565&D2 (WHP) (DOE 2012) for evaluation and processing to determine a final pathway for disposal. Population 7 (POP 7) consists of 56 containers of aged, low-level and potentially mixed S&M waste that has been staged in various locations around ORNL. Several of these POP 7 containers primarily contain personal protective equipment (PPE) and dry active waste (DAW), but may contain other miscellaneous debris. This data sharing report addresses the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) specified waste in a 13-container subpopulation (including eight steel boxes, three 55-gal drums, one sealand, and one intermodal) that lacked sufficient characterization data for possible disposal at the Environmental Management Waste Management Facility (EMWMF) using the approved Waste Lot (WL) 108.1 profile.

Adaptive laboratory evolution – principles and applications for biotechnology

Science.gov (United States)

2013-01-01

Adaptive laboratory evolution is a frequent method in biological studies to gain insights into the basic mechanisms of molecular evolution and adaptive changes that accumulate in microbial populations during long term selection under specified growth conditions. Although regularly performed for more than 25 years, the advent of transcript and cheap next-generation sequencing technologies has resulted in many recent studies, which successfully applied this technique in order to engineer microbial cells for biotechnological applications. Adaptive laboratory evolution has some major benefits as compared with classical genetic engineering but also some inherent limitations. However, recent studies show how some of the limitations may be overcome in order to successfully incorporate adaptive laboratory evolution in microbial cell factory design. Over the last two decades important insights into nutrient and stress metabolism of relevant model species were acquired, whereas some other aspects such as niche-specific differences of non-conventional cell factories are not completely understood. Altogether the current status and its future perspectives highlight the importance and potential of adaptive laboratory evolution as approach in biotechnological engineering. PMID:23815749

Behavioral Economic Laboratory Research in Tobacco Regulatory Science.

Science.gov (United States)

Tidey, Jennifer W; Cassidy, Rachel N; Miller, Mollie E; Smith, Tracy T

2016-10-01

Research that can provide a scientific foundation for the United States Food and Drug Administration (FDA) tobacco policy decisions is needed to inform tobacco regulatory policy. One factor that affects the impact of a tobacco product on public health is its intensity of use, which is determined, in part, by its abuse liability or reinforcing efficacy. Behavioral economic tasks have considerable utility for assessing the reinforcing efficacy of current and emerging tobacco products. This paper provides a narrative review of several behavioral economic laboratory tasks and identifies important applications to tobacco regulatory science. Behavioral economic laboratory assessments, including operant self-administration, choice tasks and purchase tasks, can be used generate behavioral economic data on the effect of price and other constraints on tobacco product consumption. These tasks could provide an expedited simulation of the effects of various tobacco control policies across populations of interest to the FDA. Tobacco regulatory research questions that can be addressed with behavioral economic tasks include assessments of the impact of product characteristics on product demand, assessments of the abuse liability of novel and potential modified risk tobacco products (MRTPs), and assessments of the impact of conventional and novel products in vulnerable populations.

Field and laboratory evaluations of soybean lines against soybean aphid (Hemiptera: Aphididae).

Science.gov (United States)

Hesler, Louis S; Prischmann, Deirdre A; Dashiell, Kenton E

2012-04-01

The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is a major pest of soybean, Glycine max (L.). Merr., that significantly reduces yield in northern production areas of North America. Insecticides are widely used to control soybean aphid outbreaks, but efforts are underway to develop host plant resistance as an effective alternative management strategy. Here, previously identified resistant lines were evaluated in laboratory tests against field-collected populations of soybean aphid and in field-plot tests over 2 yr in South Dakota. Six lines previously identified with resistance to soybean aphid--Jackson, Dowling, K1639, Cobb, Palmetto and Sennari--were resistant in this study, but relatively high aphid counts on Tie-feng 8 in field plots contrasted with its previously reported resistance. Bhart-PI 165989 showed resistance in one of two laboratory tests, but it had relatively large aphid infestations in both years of field tests. Intermediate levels of soybean aphid occurred in field plots on lines previously shown to have strong (Sugao Zairai, PI 230977, and D75-10169) or moderate resistance to soybean aphid (G93-9223, Bragg, Braxton, and Tracy-M). Sugao Zairai also failed to have a significant proportion of resistant plants in two laboratory tests against aphids field-collected in 2008, but it was resistant in laboratory tests with aphids collected in 2002, 2005, and 2006. Overall, results showed that lines with Rag (i.e., Jackson) or Rag1 gene (i.e., Dowling) had low aphid numbers, whereas lines with Rag2 (i.e., Sugao Zairai, Sennari) had mixed results. Collectively, responses of soybean aphid populations in laboratory and field tests in 2008 resembled a virulence pattern reported previously for biotype 3 soybean aphids, but virulence in soybean aphid populations was variable and dynamic over years of the study. These results, coupled with previous reports of biotypes virulent to Rag1, suggest that deployment of lines with a single aphid

First autochthonous case of canine visceral leishmaniasis in Volta Redonda, Rio de Janeiro, Brazil

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Monique Paiva de Campos

Full Text Available In Brazil, American visceral leishmaniasis (AVL is caused byLeishmania (Leishmania chagasi and its main vector isLutzomyia longipalpis. Cases of canine visceral leishmaniasis (CVL in non-endemic areas have been reported over the last few years throughout the country. The objective of this research note is to describe an autochthonous case of CVL that occurred in the municipality of Volta Redonda, state of Rio de Janeiro, an area where the disease is not endemic, alerting veterinarians and the scientific community to the expansion of this important zoonosis and advising veterinary practitioners on how to deal with a suspicion of CVL. Canine visceral leishmaniasis can be misdiagnosed within a broad spectrum of canine diseases based on clinical and laboratory findings. Therefore, knowledge of its clinical manifestations, specific and sensitive laboratory diagnostic tests and parasitological procedures are of the utmost importance for rapid confirmation and notification of a case, thus contributing directly to the control of a focus.

Reduction in laboratory turnaround time decreases emergency room length of stay

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Kaushik N

2018-04-01

Full Text Available Nitin Kaushik,1 Victor S Khangulov,2 Matthew O’Hara,2 Ramy Arnaout3,4 1Becton, Dickinson and Company, Franklin Lakes, NJ, USA; 2Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, MA, USA; 3Department of Pathology, 4Division of Biomedical Informatics, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA USA Objective: Laboratory tests are an important contributor to treatment decisions in the emergency department (ED. Rapid turnaround of laboratory tests can optimize ED throughout by reducing the length of stay (LOS and improving patient outcomes. Despite evidence supporting the effect of shorter turnaround time (TAT on LOS and outcomes, there is still a lack of large retrospective studies examining these associations. Here, we evaluated the effect of a reduction in laboratory TAT on ED LOS using retrospective analysis of Electronic Health Records (EHR. Materials and methods: Retrospective analysis of ED encounters from a large, US-based, de-identified EHR database and a separate analysis of ED encounters from the EHR of an ED at a top-tier tertiary care center were performed. Additionally, an efficiency model calculating the cumulative potential LOS time savings and resulting financial opportunity due to laboratory TAT reduction was created, assuming other factors affecting LOS are constant. Results: Multivariate regression analysis of patients from the multisite study showed that a 1-minute decrease in laboratory TAT was associated with 0.50 minutes of decrease in LOS. The single-site analysis confirmed our findings from the multisite analysis that a positive correlation between laboratory TAT and ED LOS exists in the ED population as a whole, as well as across different patient acuity levels. In addition, based on the calculations from the efficiency model, for a 5-, 10- and 15-minute TAT reduction, the single-site ED can potentially admit a total of 127, 256 and 386 additional

Comparative analysis of carbohydrate residues in the midgut of phlebotomines (Diptera: Psychodidae) from colony and field populations from Amazon, Brazil.

Science.gov (United States)

de Oliveira, Davi Marcos Souza; da Silva, Bruno José Martins; de Sena, Chubert Bernardo Castro; Lima, José Aprígio Nunes; Vasconcelos Dos Santos, Thiago; Silveira, Fernando Tobias; Silva, Edilene Oliveira

2016-09-01

Leishmaniasis are worldwide diseases that occur in 98 countries including Brazil, transmitted by the bite of female phlebotomines during blood feeding. In Brazil it is known that some species of sand flies as Lutzomyia longipalpis sensun latum (vector of Leishmania infantum chagasi), Lutzomyia flaviscutellata (vector of Leishmania (Leishmania) amazonensis) and Lutzomyia antunesi [suspected vector of Leishmania (Viannia) lindenbergi] are incriminated of transmitting the parasite Leishmania for the vertebrate host. The phlebotomine-parasite is mediated by the attachment of the promastigote lipophosphoglycan (LPG) to the midgut epithelium. However, another mechanism that is LPG-independent and mediated by N-acetyl-galactosamine (GalNAc) seems to occur in some species of phlebotomines that are classified as permissive. The aim of this study was to characterize the carbohydrate residues that, probably, play a role in parasite attachment to the midgut of phlebotomine from colony and field populations from the Brazilian Amazonian region. We observed the presence of GalNAc, mannose, galactose and GlcNAc in all phlebotomine species. A binding assay between L. (L.) amazonensis and L. i.chagasi to the midguts of different species of phlebotomines was performed. The attachment of both Leishmania and vector species suggests the presence of GalNAc on the midgut surfaces. Thus, these results suggested that GalNAc is a possible binding sites of Leishmania in sand flies from the Brazilian Amazonian region. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparison of microbiological diagnosis of urinary tract infection in young children by routine health service laboratories and a research laboratory: Diagnostic cohort study

Science.gov (United States)

Birnie, Kate; Hay, Alastair D.; Wootton, Mandy; Howe, Robin; MacGowan, Alasdair; Whiting, Penny; Lawton, Michael; Delaney, Brendan; Downing, Harriet; Dudley, Jan; Hollingworth, William; Lisles, Catherine; Little, Paul; O’Brien, Kathryn; Pickles, Timothy; Rumsby, Kate; Thomas-Jones, Emma; Van der Voort, Judith; Waldron, Cherry-Ann; Harman, Kim; Hood, Kerenza; Butler, Christopher C.; Sterne, Jonathan A. C.

2017-01-01

Objectives To compare the validity of diagnosis of urinary tract infection (UTI) through urine culture between samples processed in routine health service laboratories and those processed in a research laboratory. Population and methods We conducted a prospective diagnostic cohort study in 4808 acutely ill children aged <5 years attending UK primary health care. UTI, defined as pure/predominant growth ≥105 CFU/mL of a uropathogen (the reference standard), was diagnosed at routine health service laboratories and a central research laboratory by culture of urine samples. We calculated areas under the receiver-operator curve (AUC) for UTI predicted by pre-specified symptoms, signs and dipstick test results (the “index test”), separately according to whether samples were obtained by clean catch or nappy (diaper) pads. Results 251 (5.2%) and 88 (1.8%) children were classified as UTI positive by health service and research laboratories respectively. Agreement between laboratories was moderate (kappa = 0.36; 95% confidence interval [CI] 0.29, 0.43), and better for clean catch (0.54; 0.45, 0.63) than nappy pad samples (0.20; 0.12, 0.28). In clean catch samples, the AUC was lower for health service laboratories (AUC = 0.75; 95% CI 0.69, 0.80) than the research laboratory (0.86; 0.79, 0.92). Values of AUC were lower in nappy pad samples (0.65 [0.61, 0.70] and 0.79 [0.70, 0.88] for health service and research laboratory positivity, respectively) than clean catch samples. Conclusions The agreement of microbiological diagnosis of UTI comparing routine health service laboratories with a research laboratory was moderate for clean catch samples and poor for nappy pad samples and reliability is lower for nappy pad than for clean catch samples. Positive results from the research laboratory appear more likely to reflect real UTIs than those from routine health service laboratories, many of which (particularly from nappy pad samples) could be due to contamination. Health service

Bioassay Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Bioassay Laboratory is an accredited laboratory capable of conducting standardized and innovative environmental testing in the area of aquatic ecotoxicology. The...

HYDROMECHANICS LABORATORY

Data.gov (United States)

Federal Laboratory Consortium — Naval Academy Hydromechanics LaboratoryThe Naval Academy Hydromechanics Laboratory (NAHL) began operations in Rickover Hall in September 1976. The primary purpose of...

Natural infection of phlebotomines (Diptera: Psychodidae) by Leishmania (Leishmania) amazonensis in an area of ecotourism in Central-Western Brazil.

Science.gov (United States)

Brilhante, Andreia Fernandes; Nunes, Vânia Lúcia Brandão; Kohatsu, Kleber Augusto; Galati, Eunice Aparecida Bianchi; Rocca, Maria Elizabeth Ghizzi; Ishikawa, Edna Aoba Yassui

2015-01-01

Bonito municipality, known as an area of ecoturism, in Mato Grosso do Sul state, Brazil, is also a focus of visceral and cutaneous leishmaniases, with cases registered in both human and canine populations. This study sought to investigate natural infection by flagellate forms of Leishmania in phlebotomines of the urban area of Bonito. Sand flies were collected fortnightly from October 2005 to July 2006 with modified automatic light traps installed in peridomiciles and animal shelters in the center and on the outskirts of the city. The females were dissected and their guts observed under an optical microscope. A total of 1977 specimens were captured, Lutzomyia longipalpis (88.4 %) and Bichromomyia flaviscutelata (3.0 %) being the most frequent species. Bi. flaviscutellata was found infected by flagellates that were identified as Leishmania (Leishmania) amazonensis by indirect immunofluorescence reaction, employing monoclonal antibodies and the biotin-avidin system. This is the first report of natural infection by L. amazonensis in Bi. flaviscutellata in a Brazilian urban area. As Bi. flaviscutellata is only slightly attracted by humans, the transmission of L. amazonensis in the study area may have a zoonotic character; however, the sympatric occurrence of this parasite and Lu. longipalpis should be taken into consideration by the local health authorities since this sand fly has already been found with L. amazonensis DNA in a focus of canine visceral leishmaniasis in Bonito municipality.

Spectroscopy of X-ray Photoionized Plasmas in the Laboratory

Science.gov (United States)

Liedahl, Duane A.; Loisel, Guillaume; Bailey, James E.; Nagayama, Taisuke; Hansen, Stephanie B.; Rochau, Gregory; Fontes, Christopher J.; Mancini, Roberto; Kallman, Timothy R.

2018-06-01

The physical processes operating in astrophysical plasmas --- heating, cooling, ionization, recombination, level population kinetics, and radiation transport --- are all accessible to observation in the laboratory. What distinguishes X-ray photoionized plasmas from the more common case of high-temperature collisionally-ionized plasmas is the elevated level of importance of the radiation/matter interaction. The advent of laboratory facilities with the capability to generate high-powered X-ray sources has provided the means by which to study this interaction, which is also fundamental to active galactic nuclei and other accretion-powered objects. We discuss recent and ongoing experiments, with an emphasis on X-ray spectroscopic measurements of silicon plasmas obtained at the Sandia Z Pulsed Power Facility.

Annual environmental monitoring report of the Lawrence Berkeley Laboratory

International Nuclear Information System (INIS)

Schleimer, G.E.

1983-04-01

In order to establish whether LBL research activities produces any impact on the population surrounding the Laboratory, a program of environmental air and water sampling and continuous radiation monitoring was carried on throughout the year. For 1982, as in the previous several years, doses attributable to LBL radiological operations were a small fraction of the relevant radiation protection guidelines (RPG). The maximum perimeter dose equivalent was less than or equal to 24.0 mrem (the 1982 dose equivalent measured at the Building 88 monitoring station B-13A, about 5% of the RPG). The total population dose equivalent attributable to LBL operations during 1982 was less than or equal to 16 man-rem, about 0.002% of the RPG of 170 mrem/person to a suitable sample of the population

A laboratory and field condition comparison of life table parameters of Aphis gossypii Glover (Hemiptera: Aphididae

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Hosseini-Tabesh Behnaz

2015-01-01

Full Text Available Life table studies are essential tools for understanding population dynamics. The life table parameters of Aphis gossypii Glover (Hemiptera: Aphididae feeding on the host plant, Hibiscus syriacus L. were studied under laboratory (25±1°C and relative humidity of 65±5% and a photoperiod of 16L : 8D h and field conditions (23-43°C, and relative humidity of 27-95%. The data were analysed using the age-stage, two-sex life table theory. The life table studies were started with 50 and 40 nymphs in laboratory and field conditions, respectively. Under laboratory conditions, A. gossypii reared on H. syriacus had a higher survival rate, fecundity, and longevity than those reared under field conditions. When reared under field conditions, A. gossypii had a longer nymphal developmental time, shorter adult longevity, and lower fecundity than those reared under laboratory conditions. The intrinsic rate of increase (r, net reproductive rate (R0, and the finite rate of increase (λ under laboratory conditions, were higher than those obtained under field conditions. Nevertheless, there were no significant differences in the mean generation time T (days between field and laboratory conditions. In the present study, the results clearly showed that life table parameters of A. gossypii were significantly different under field and laboratory conditions. These results could help us to understand the A. gossypii population dynamics under field conditions. The results could also help us make better management decisions for economically important crops

Prolonged stress induces adaptation of drosophila population to ionizing radiation

International Nuclear Information System (INIS)

Mosse, I. B.; Glushkova, I. V.; Aksyutik, T. V.

2003-01-01

We studied natural populations of Drosophila melanogaster from radio-contaminated area (Vetka district of Gomel region with 24 Ci/km 2 of 137 Cs and 0.5 Cu/km 2 of 90 Sr) and from Berezynski Natural Reserve as a control area (region of Chernobyl catastrophe). Population samples were caught in 2000-2001 years. Natural insect populations from radio-contaminated areas are more resistant to additional irradiation than control populations. Keeping of natural populations under laboratory or vivarium conditions is a strong stress (limited space, overpopulation, other than in nature temperature and light conditions), which increases mutation process and induces unspecific adaptation. (authors)

How do laboratory technicians perceive their role in tuberculosis diagnostic process: a cross-sectional study among laboratory technicians in health centers of Central Java Province, Indonesia

Directory of Open Access Journals (Sweden)

Widjanarko B

2016-09-01

Full Text Available Bagoes Widjanarko,1 Dyah Anantalia Widyastari,2 Martini Martini,3 Praba Ginandjar3 1Department of Health Education and Behavior Sciences, Faculty of Public Health, Diponegoro University, Semarang, Indonesia; 2Institute for Population and Social Research, Mahidol University, Salaya, Thailand; 3Department of Epidemiology, Faculty of Public Health, Diponegoro University, Semarang, Indonesia Purpose: Detection of acid-fast bacilli in respiratory specimens serves as an initial pulmonary tuberculosis (TB diagnosis. Laboratories are the essential and fundamental part of all health systems. This study aimed to describe how laboratory technicians perceived their own self and work. This included perceived self-efficacy, perceived role, perceived equipment availability, perceived procedures, perceived reward and job, and perceived benefit of health education, as well as level of knowledge and attitudes related to work performance of laboratory technicians.Methods: This was a cross-sectional quantitative study involving 120 laboratory technicians conducted in Central Java. Interviews and observation were conducted to measure performance and work-related variables.Results: Among 120 laboratory technicians, 43.3% showed fairly good performance. They complied with 50%–75% of all procedures, including sputum collection, laboratory tools utilization, sputum smearing, staining, smear examination, grading of results, and universal precaution practice. Perceived role, perceived self-efficacy, and knowledge of laboratory procedures were significantly correlated to performance, besides education and years of working as a laboratory technician. Perceived equipment availability was also significantly correlated to performance after the education variable was controlled.Conclusion: Most of the laboratory technicians believed that they have an important role in TB patients’ treatment and should display proper self-efficacy in performing laboratory activities. The

Population modelling to compare chronic external radiotoxicity between individual and population endpoints in four taxonomic groups

International Nuclear Information System (INIS)

Alonzo, Frédéric; Hertel-Aas, Turid; Real, Almudena; Lance, Emilie; Garcia-Sanchez, Laurent; Bradshaw, Clare; Vives i Batlle, Jordi; Oughton, Deborah H.; Garnier-Laplace, Jacqueline

2016-01-01

In this study, we modelled population responses to chronic external gamma radiation in 12 laboratory species (including aquatic and soil invertebrates, fish and terrestrial mammals). Our aim was to compare radiosensitivity between individual and population endpoints and to examine how internationally proposed benchmarks for environmental radioprotection protected species against various risks at the population level. To do so, we used population matrix models, combining life history and chronic radiotoxicity data (derived from laboratory experiments and described in the literature and the FREDERICA database) to simulate changes in population endpoints (net reproductive rate R_0, asymptotic population growth rate λ, equilibrium population size N_e_q) for a range of dose rates. Elasticity analyses of models showed that population responses differed depending on the affected individual endpoint (juvenile or adult survival, delay in maturity or reduction in fecundity), the considered population endpoint (R_0, λ or N_e_q) and the life history of the studied species. Among population endpoints, net reproductive rate R_0 showed the lowest EDR_1_0 (effective dose rate inducing 10% effect) in all species, with values ranging from 26 μGy h"−"1 in the mouse Mus musculus to 38,000 μGy h"−"1 in the fish Oryzias latipes. For several species, EDR_1_0 for population endpoints were lower than the lowest EDR_1_0 for individual endpoints. Various population level risks, differing in severity for the population, were investigated. Population extinction (predicted when radiation effects caused population growth rate λ to decrease below 1, indicating that no population growth in the long term) was predicted for dose rates ranging from 2700 μGy h"−"1 in fish to 12,000 μGy h"−"1 in soil invertebrates. A milder risk, that population growth rate λ will be reduced by 10% of the reduction causing extinction, was predicted for dose rates ranging from 24 μGy h"−"1

Diagnostic trends in Clostridium difficile detection in Finnish microbiology laboratories.

Science.gov (United States)

Könönen, Eija; Rasinperä, Marja; Virolainen, Anni; Mentula, Silja; Lyytikäinen, Outi

2009-12-01

Due to increased interest directed to Clostridium difficile-associated infections, a questionnaire survey of laboratory diagnostics of toxin-producing C. difficile was conducted in Finland in June 2006. Different aspects pertaining to C. difficile diagnosis, such as requests and criteria used for testing, methods used for its detection, yearly changes in diagnostics since 1996, and the total number of investigations positive for C. difficile in 2005, were asked in the questionnaire, which was sent to 32 clinical microbiology laboratories, including all hospital-affiliated and the relevant private clinical microbiology laboratories in Finland. The situation was updated by phone and email correspondence in September 2008. In June 2006, 28 (88%) laboratories responded to the questionnaire survey; 24 of them reported routinely testing requested stool specimens for C. difficile. Main laboratory methods included toxin detection (21/24; 88%) and/or anaerobic culture (19/24; 79%). In June 2006, 18 (86%) of the 21 laboratories detecting toxins directly from feces, from the isolate, or both used methods for both toxin A (TcdA) and B (TcdB), whereas only one laboratory did so in 1996. By September 2008, all of the 23 laboratories performing diagnostics for C. difficile used methods for both TcdA and TcdB. In 2006, the number of specimens processed per 100,000 population varied remarkably between different hospital districts. In conclusion, culturing C. difficile is common and there has been a favorable shift in toxin detection practice in Finnish clinical microbiology laboratories. However, the variability in diagnostic activity reported in 2006 creates a challenge for national monitoring of the epidemiology of C. difficile and related diseases.

Laboratory quality assurance

International Nuclear Information System (INIS)

Delvin, W.L.

1977-01-01

The elements (principles) of quality assurance can be applied to the operation of the analytical chemistry laboratory to provide an effective tool for indicating the competence of the laboratory and for helping to upgrade competence if necessary. When used, those elements establish the planned and systematic actions necessary to provide adequate confidence in each analytical result reported by the laboratory (the definition of laboratory quality assurance). The elements, as used at the Hanford Engineering Development Laboratory (HEDL), are discussed and they are qualification of analysts, written methods, sample receiving and storage, quality control, audit, and documentation. To establish a laboratory quality assurance program, a laboratory QA program plan is prepared to specify how the elements are to be implemented into laboratory operation. Benefits that can be obtained from using laboratory quality assurance are given. Experience at HEDL has shown that laboratory quality assurance is not a burden, but it is a useful and valuable tool for the analytical chemistry laboratory

How Large Asexual Populations Adapt

Science.gov (United States)

Desai, Michael

2007-03-01

We often think of beneficial mutations as being rare, and of adaptation as a sequence of selected substitutions: a beneficial mutation occurs, spreads through a population in a selective sweep, then later another beneficial mutation occurs, and so on. This simple picture is the basis for much of our intuition about adaptive evolution, and underlies a number of practical techniques for analyzing sequence data. Yet many large and mostly asexual populations -- including a wide variety of unicellular organisms and viruses -- live in a very different world. In these populations, beneficial mutations are common, and frequently interfere or cooperate with one another as they all attempt to sweep simultaneously. This radically changes the way these populations adapt: rather than an orderly sequence of selective sweeps, evolution is a constant swarm of competing and interfering mutations. I will describe some aspects of these dynamics, including why large asexual populations cannot evolve very quickly and the character of the diversity they maintain. I will explain how this changes our expectations of sequence data, how sex can help a population adapt, and the potential role of ``mutator'' phenotypes with abnormally high mutation rates. Finally, I will discuss comparisons of these predictions with evolution experiments in laboratory yeast populations.

Field and Laboratory Evaluations of Insecticides for Southern Pine Beetle Control

Science.gov (United States)

Felton L. Hastings; Jack E. Coster; [Editors

1981-01-01

Reports results of laboratory screenings and field studies of insecticides for use against the southern pine beetle. Preventive as webas remedial efficacywere observed, along with phytotoxicity to pine and understory hardwood species, effects of insecticides on soil microbial and mesofaunal populations, and degradation of insecticides by selected soil microbes.

A User Assessment of Workspaces in Selected Music Education Computer Laboratories.

Science.gov (United States)

Badolato, Michael Jeremy

A study of 120 students selected from the user populations of four music education computer laboratories was conducted to determine the applicability of current ergonomic and environmental design guidelines in satisfying the needs of users of educational computing workspaces. Eleven categories of workspace factors were organized into a…

Population exposure from the nuclear fuel cycle

International Nuclear Information System (INIS)

Alpen, E.L.; Chester, R.O.; Fisher, D.R.

1988-01-01

The papers in this volume reflect the latest research on the nature and degree of exposure to human populations from ionizing radiation that results from the production of commercial nuclear power. The conference comprised representatives from such notable organizations as Brookhaven National Laboratory, the Inhalation Toxicology Research Institute and Pacific Northwest Laboratories. Issues addressed include the effects on humans of the mining and extraction of uranium and the fabrication of fuel for nuclear reactors, the decommissioning and disposal of facilities that are no longer useful or efficient and the likelihood of major nuclear accidents. Each document will have to be cataloged separately

Feedback between Population and Evolutionary Dynamics Determines the Fate of Social Microbial Populations

Science.gov (United States)

Sanchez, Alvaro; Gore, Jeff

2013-01-01

The evolutionary spread of cheater strategies can destabilize populations engaging in social cooperative behaviors, thus demonstrating that evolutionary changes can have profound implications for population dynamics. At the same time, the relative fitness of cooperative traits often depends upon population density, thus leading to the potential for bi-directional coupling between population density and the evolution of a cooperative trait. Despite the potential importance of these eco-evolutionary feedback loops in social species, they have not yet been demonstrated experimentally and their ecological implications are poorly understood. Here, we demonstrate the presence of a strong feedback loop between population dynamics and the evolutionary dynamics of a social microbial gene, SUC2, in laboratory yeast populations whose cooperative growth is mediated by the SUC2 gene. We directly visualize eco-evolutionary trajectories of hundreds of populations over 50–100 generations, allowing us to characterize the phase space describing the interplay of evolution and ecology in this system. Small populations collapse despite continual evolution towards increased cooperative allele frequencies; large populations with a sufficient number of cooperators “spiral” to a stable state of coexistence between cooperator and cheater strategies. The presence of cheaters does not significantly affect the equilibrium population density, but it does reduce the resilience of the population as well as its ability to adapt to a rapidly deteriorating environment. Our results demonstrate the potential ecological importance of coupling between evolutionary dynamics and the population dynamics of cooperatively growing organisms, particularly in microbes. Our study suggests that this interaction may need to be considered in order to explain intraspecific variability in cooperative behaviors, and also that this feedback between evolution and ecology can critically affect the demographic fate

feedback between population and evolutionary dynamics determines the fate of social microbial populations.

Directory of Open Access Journals (Sweden)

Alvaro Sanchez

Full Text Available The evolutionary spread of cheater strategies can destabilize populations engaging in social cooperative behaviors, thus demonstrating that evolutionary changes can have profound implications for population dynamics. At the same time, the relative fitness of cooperative traits often depends upon population density, thus leading to the potential for bi-directional coupling between population density and the evolution of a cooperative trait. Despite the potential importance of these eco-evolutionary feedback loops in social species, they have not yet been demonstrated experimentally and their ecological implications are poorly understood. Here, we demonstrate the presence of a strong feedback loop between population dynamics and the evolutionary dynamics of a social microbial gene, SUC2, in laboratory yeast populations whose cooperative growth is mediated by the SUC2 gene. We directly visualize eco-evolutionary trajectories of hundreds of populations over 50-100 generations, allowing us to characterize the phase space describing the interplay of evolution and ecology in this system. Small populations collapse despite continual evolution towards increased cooperative allele frequencies; large populations with a sufficient number of cooperators "spiral" to a stable state of coexistence between cooperator and cheater strategies. The presence of cheaters does not significantly affect the equilibrium population density, but it does reduce the resilience of the population as well as its ability to adapt to a rapidly deteriorating environment. Our results demonstrate the potential ecological importance of coupling between evolutionary dynamics and the population dynamics of cooperatively growing organisms, particularly in microbes. Our study suggests that this interaction may need to be considered in order to explain intraspecific variability in cooperative behaviors, and also that this feedback between evolution and ecology can critically affect the

Population specific fitness response of Drosophila subobscura to lead pollution.

Science.gov (United States)

Kenig, Bojan; Stamenković-Radak, Marina; Andelković, Marko

2013-04-01

Differences in heavy metal tolerance among separate populations of the same species have often been interpreted as local adaptation. Persistence of differences after removing the stressor indicates that mechanisms responsible for the increased tolerance were genetically determined. Drosophila subobscura Collin (Diptera: Drosophilidae) populations were sampled from two localities with different history of heavy metal pollution, and reared for eight generations in the laboratory on a standard medium and on media with different concentrations of lead (Pb). To determine whether flies from different natural populations exposed to the Pb-contaminated media in the laboratory show population specific variability in fitness components over generations, experimental groups with different concentrations of lead were assayed in three generations (F2 , F5 , and F8 ) for fecundity, developmental time, and egg-to-adult viability. On the contaminated medium, fecundity was reduced in later generations and viability was increased, irrespective of the environmental origin of populations. For both populations, developmental time showed a tendency of slowing down on media with lead. Faster development was observed in later generations. Preadaptation to contamination, meaning higher fecundity, higher viability, and faster egg to adult development in all studied generations, was found in D. subobscura originating from the locality with a higher level of heavy metal pollution. © 2012 The Authors Insect Science © 2012 Institute of Zoology, Chinese Academy of Sciences.

Biosecurity management recommendations for rinderpest laboratories

Energy Technology Data Exchange (ETDEWEB)

Brodsky, Benjamin H [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Caskey, Susan Adele [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Arndt, William [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2014-10-01

Rinderpest is a virus that can affect cattle and other even toes ungulates; evidence of outbreaks from over 10,000 years ago highlights the potential impact of this virus. During the 18th century, Rinderpest caused huge losses in cattle throughout Europe. Starting in the mid 1900’s vaccination efforts seemed feasible and work was initiated to vaccinate large populations of cattle. Walter Plowright received numerous awards for updating the Rinderpest vaccine which many believed would be the key to eradication. Vaccination of the disease lead to a massive drop in outbreaks and the last confirmed case of Rinderpest in Asia was in 2000 and in Africa in 2001.1 At this point, Rinderpest has been declared eradicated from nature. However, stocks of the virus are still in many laboratories.2 Rinderpest was investigated as a biological weapon agent during the Second World War. However, following WWII, rinderpest was not considered a high risk as a biological weapon as there was no direct military advantage. Now, with the concern of the use of biological agents as weapons in acts of terrorism, concern regarding rinderpest has resurfaced. Since the eradication of this virus, cattle populations are highly susceptibility to the virus and the economic impacts would be significant. This paper will discuss the specific nature of the terrorism risks associated with rinderpest; and based upon those risks provide recommendations regarding biosecurity management. The biosecurity management measures will be defined in a manner to align with the CWA 15793: the laboratory biorisk management document.

An automated image analysis system to measure and count organisms in laboratory microcosms.

Directory of Open Access Journals (Sweden)

François Mallard

Full Text Available 1. Because of recent technological improvements in the way computer and digital camera perform, the potential use of imaging for contributing to the study of communities, populations or individuals in laboratory microcosms has risen enormously. However its limited use is due to difficulties in the automation of image analysis. 2. We present an accurate and flexible method of image analysis for detecting, counting and measuring moving particles on a fixed but heterogeneous substrate. This method has been specifically designed to follow individuals, or entire populations, in experimental laboratory microcosms. It can be used in other applications. 3. The method consists in comparing multiple pictures of the same experimental microcosm in order to generate an image of the fixed background. This background is then used to extract, measure and count the moving organisms, leaving out the fixed background and the motionless or dead individuals. 4. We provide different examples (springtails, ants, nematodes, daphnia to show that this non intrusive method is efficient at detecting organisms under a wide variety of conditions even on faintly contrasted and heterogeneous substrates. 5. The repeatability and reliability of this method has been assessed using experimental populations of the Collembola Folsomia candida. 6. We present an ImageJ plugin to automate the analysis of digital pictures of laboratory microcosms. The plugin automates the successive steps of the analysis and recursively analyses multiple sets of images, rapidly producing measurements from a large number of replicated microcosms.

Population dynamics of light-limited phytoplankton : Microcosm experiments

NARCIS (Netherlands)

Huisman, Jef

This paper investigates the extent to which the predictions of an elementary model for light-limited growth are matched by laboratory experiments with light-limited phytoplankton. The model and experiments link the population dynamics of phytoplankton species with changes in the light gradient

75 FR 80011 - Good Laboratory Practice for Nonclinical Laboratory Studies

Science.gov (United States)

2010-12-21

.... FDA-2010-N-0548] Good Laboratory Practice for Nonclinical Laboratory Studies AGENCY: Food and Drug... (FDA) is seeking comment on whether to amend the regulations governing good laboratory practices (GLPs..., 1978 (43 FR 60013). As stated in its scope (Sec. 58.1), this regulation prescribes good laboratory...

Prehistoric Rock Structures of the Idaho National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Brenda R Pace

2007-04-01

Over the past 13,500 years, human populations have lived in and productively utilized the natural resources offered by the cold desert environment of the northeastern Snake River Plain in eastern Idaho. Within an overall framework of hunting and gathering, groups relied on an intimate familiarity with the natural world and developed a variety of technologies to extract the resources that they needed to survive. Useful items were abundant and found everywhere on the landscape. Even the basaltic terrain and the rocks, themselves, were put to productive use. This paper presents a preliminary classification scheme for rock structures built on the Idaho National Laboratory landscape by prehistoric aboriginal populations, including discussions of the overall architecture of the structures, associated artifact assemblages, and topographic placement. Adopting an ecological perspective, the paper concludes with a discussion of the possible functions of these unique resources for the desert populations that once called the INL home.

Rapid genetic erosion in pollutant-exposed experimental chironomid populations

Energy Technology Data Exchange (ETDEWEB)

Nowak, Carsten [Abteilung Okologie und Evolution, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: cnowak@senckenberg.de; Vogt, Christian [Abteilung Aquatische Okotoxikologie, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: vogt@bio.uni-frankfurt.de; Pfenninger, Markus [Abteilung Okologie und Evolution, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: pfenninger@bio.uni-frankfurt.de; Schwenk, Klaus [Abteilung Okologie und Evolution, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: k.schwenk@bio.uni-frankfurt.de; Oehlmann, Joerg [Abteilung Aquatische Okotoxikologie, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: oehlmann@bio.uni-frankfurt.de; Streit, Bruno [Abteilung Okologie und Evolution, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: streit@bio.uni-frankfurt.de; Oetken, Matthias [Abteilung Aquatische Okotoxikologie, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: oetken@bio.uni-frankfurt.de

2009-03-15

Few studies have evaluated how effectively environmental contamination may reduce genetic diversity of a population. Here, we chose a laboratory approach in order to test if tributyltin (TBT) exposure at environmentally relevant concentrations leads to reduced genetic variation in the midge Chironomus riparius. Two TBT-exposed and two unexposed experimental populations were reared simultaneously in the laboratory for 12 generations. We recorded several life-history traits in each generation and monitored genetic variation over time using five variable microsatellite markers. TBT-exposed strains showed increased larval mortality (treatments: 43.8%; controls: 27.8%), slightly reduced reproductive output, and delayed larval development. Reduction of genetic variation was strongest and only significant in the TBT-exposed strains (treatments: -45.9%, controls: -24.4% of initial heterozygosity) after 12 generations. Our findings document that chemical pollution may lead to a rapid decrease in genetic diversity, which has important implications for conservation strategies and ecological management in polluted environments. - Chronic TBT exposure reduces allelic variation at five variable microsatellite loci in experimental populations of Chironomus riparius.

Rapid genetic erosion in pollutant-exposed experimental chironomid populations

International Nuclear Information System (INIS)

Nowak, Carsten; Vogt, Christian; Pfenninger, Markus; Schwenk, Klaus; Oehlmann, Joerg; Streit, Bruno; Oetken, Matthias

2009-01-01

Few studies have evaluated how effectively environmental contamination may reduce genetic diversity of a population. Here, we chose a laboratory approach in order to test if tributyltin (TBT) exposure at environmentally relevant concentrations leads to reduced genetic variation in the midge Chironomus riparius. Two TBT-exposed and two unexposed experimental populations were reared simultaneously in the laboratory for 12 generations. We recorded several life-history traits in each generation and monitored genetic variation over time using five variable microsatellite markers. TBT-exposed strains showed increased larval mortality (treatments: 43.8%; controls: 27.8%), slightly reduced reproductive output, and delayed larval development. Reduction of genetic variation was strongest and only significant in the TBT-exposed strains (treatments: -45.9%, controls: -24.4% of initial heterozygosity) after 12 generations. Our findings document that chemical pollution may lead to a rapid decrease in genetic diversity, which has important implications for conservation strategies and ecological management in polluted environments. - Chronic TBT exposure reduces allelic variation at five variable microsatellite loci in experimental populations of Chironomus riparius

Idaho National Engineering Laboratory site development plan

International Nuclear Information System (INIS)

1994-09-01

This plan briefly describes the 20-year outlook for the Idaho National Engineering Laboratory (INEL). Missions, workloads, worker populations, facilities, land, and other resources necessary to fulfill the 20-year site development vision for the INEL are addressed. In addition, the plan examines factors that could enhance or deter new or expanded missions at the INEL. And finally, the plan discusses specific site development issues facing the INEL, possible solutions, resources required to resolve these issues, and the anticipated impacts if these issues remain unresolved

Laboratory-acquired brucellosis

DEFF Research Database (Denmark)

Fabiansen, C.; Knudsen, J.D.; Lebech, A.M.

2008-01-01

Brucellosis is a rare disease in Denmark. We describe one case of laboratory-acquired brucellosis from an index patient to a laboratory technician following exposure to an infected blood culture in a clinical microbiology laboratory Udgivelsesdato: 2008/6/9......Brucellosis is a rare disease in Denmark. We describe one case of laboratory-acquired brucellosis from an index patient to a laboratory technician following exposure to an infected blood culture in a clinical microbiology laboratory Udgivelsesdato: 2008/6/9...

Systematic review of the global epidemiology, clinical and laboratory profile of enteric fever

Directory of Open Access Journals (Sweden)

Asma Azmatullah

2015-12-01

Full Text Available Children suffer the highest burden of enteric fever among populations in South Asian countries. The clinical features are non–specific, vary in populations, and are often difficult to distinguish clinically from other febrile illnesses, leading to delayed or inappropriate diagnosis and treatment. We undertook a systematic review to assess the clinical profile and laboratory features of enteric fever across age groups, economic regions, level of care and antibiotic susceptibility patterns.

Errors in clinical laboratories or errors in laboratory medicine?

Science.gov (United States)

Plebani, Mario

2006-01-01

Laboratory testing is a highly complex process and, although laboratory services are relatively safe, they are not as safe as they could or should be. Clinical laboratories have long focused their attention on quality control methods and quality assessment programs dealing with analytical aspects of testing. However, a growing body of evidence accumulated in recent decades demonstrates that quality in clinical laboratories cannot be assured by merely focusing on purely analytical aspects. The more recent surveys on errors in laboratory medicine conclude that in the delivery of laboratory testing, mistakes occur more frequently before (pre-analytical) and after (post-analytical) the test has been performed. Most errors are due to pre-analytical factors (46-68.2% of total errors), while a high error rate (18.5-47% of total errors) has also been found in the post-analytical phase. Errors due to analytical problems have been significantly reduced over time, but there is evidence that, particularly for immunoassays, interference may have a serious impact on patients. A description of the most frequent and risky pre-, intra- and post-analytical errors and advice on practical steps for measuring and reducing the risk of errors is therefore given in the present paper. Many mistakes in the Total Testing Process are called "laboratory errors", although these may be due to poor communication, action taken by others involved in the testing process (e.g., physicians, nurses and phlebotomists), or poorly designed processes, all of which are beyond the laboratory's control. Likewise, there is evidence that laboratory information is only partially utilized. A recent document from the International Organization for Standardization (ISO) recommends a new, broader definition of the term "laboratory error" and a classification of errors according to different criteria. In a modern approach to total quality, centered on patients' needs and satisfaction, the risk of errors and mistakes

Cooperation, cheating, and collapse in microbial populations

Science.gov (United States)

Gore, Jeff

2012-02-01

Natural populations can suffer catastrophic collapse in response to small changes in environmental conditions, and recovery after such a collapse can be exceedingly difficult. We have used laboratory yeast populations to study proposed early warning signals of impending extinction. Yeast cooperatively breakdown the sugar sucrose, meaning that there is a minimum number of cells required to sustain the population. We have demonstrated experimentally that the fluctuations in the population size increase in magnitude and become slower as the population approaches collapse. The cooperative nature of yeast growth on sucrose suggests that the population may be susceptible to cheater cells, which do not contribute to the public good and instead merely take advantage of the cooperative cells. We have confirmed this possibility experimentally by using a cheater yeast strain that lacks the gene encoding the cooperative behavior [1]. However, recent results in the lab demonstrate that the presence of a bacterial competitor may drive cooperation within the yeast population.[4pt] [1] Gore et al, Nature 459, 253 -- 256 (2009)

Quality Indicators in Laboratory Medicine: the status of the progress of IFCC Working Group "Laboratory Errors and Patient Safety" project.

Science.gov (United States)

Sciacovelli, Laura; Lippi, Giuseppe; Sumarac, Zorica; West, Jamie; Garcia Del Pino Castro, Isabel; Furtado Vieira, Keila; Ivanov, Agnes; Plebani, Mario

2017-03-01

The knowledge of error rates is essential in all clinical laboratories as it enables them to accurately identify their risk level, and compare it with those of other laboratories in order to evaluate their performance in relation to the State-of-the-Art (i.e. benchmarking) and define priorities for improvement actions. Although no activity is risk free, it is widely accepted that the risk of error is minimized by the use of Quality Indicators (QIs) managed as a part of laboratory improvement strategy and proven to be suitable monitoring and improvement tools. The purpose of QIs is to keep the error risk at a level that minimizes the likelihood of patients. However, identifying a suitable State-of-the-Art is challenging, because it calls for the knowledge of error rates measured in a variety of laboratories throughout world that differ in their organization and management, context, and the population they serve. Moreover, it also depends on the choice of the events to keep under control and the individual procedure for measurement. Although many laboratory professionals believe that the systemic use of QIs in Laboratory Medicine may be effective in decreasing errors occurring throughout the total testing process (TTP), to improve patient safety as well as to satisfy the requirements of International Standard ISO 15189, they find it difficult to maintain standardized and systematic data collection, and to promote continued high level of interest, commitment and dedication in the entire staff. Although many laboratories worldwide express a willingness to participate to the Model of QIs (MQI) project of IFCC Working Group "Laboratory Errors and Patient Safety", few systematically enter/record their own results and/or use a number of QIs designed to cover all phases of the TTP. Many laboratories justify their inadequate participation in data collection of QIs by claiming that the number of QIs included in the MQI is excessive. However, an analysis of results suggests

Worldwide Laboratory Comparison on the Determination of Trace Elements in IAEA-452 Biota Sample

International Nuclear Information System (INIS)

2012-01-01

The Marine Environmental Studies Laboratory (MESL) of the International Atomic Energy Agency's Environment Laboratories (IAEA-NAEL) has the programmatic responsibility to provide assistance to Member States' laboratories in maintaining and improving the reliability of analytical measurement results, both in trace elements and organic pollutants. This is accomplished through the provision of reference materials of marine origin, validated analytical procedures, training in the implementation of internal quality control, and through the evaluation of measurement performance by the organization of worldwide and regional interlaboratory comparison exercises. For nearly thirty years, the MESL has conducted worldwide laboratory performance studies, also known as interlaboratory comparison. The results have been used to evaluate laboratory performance with respect to a wide range of organic and inorganic pollutants, including methyl mercury. This work has been conducted in collaboration with the UNEP Regional Seas Programme. The goal of interlaboratory comparison is to demonstrate the measurement capabilities of laboratories participating in interlaboratory comparisons (ILCs) and proficiency tests (PTs). The results from ILCs or PTs are of crucial interest for laboratories as these provide clear information of its measurement capabilities. It should be pointed out that the participation is either voluntary or forced by external requirements (e.g. legal, accreditation, control bodies). NAEL's interlaboratory comparison (ILC) and proficiency test (PT) schemes involve comparison of participant's results with an assigned value, which usually is delivered as a consensus value from the overall population of test results. Those exercises are designed to monitor and demonstrate the performance and analytical capabilities of the participating laboratories, and to identify gaps and problem areas where further development is needed. Continued membership has benefits in training and

The leverage effect on wealth distribution in a controllable laboratory stock market.

Science.gov (United States)

Zhu, Chenge; Yang, Guang; An, Kenan; Huang, Jiping

2014-01-01

Wealth distribution has always been an important issue in our economic and social life, since it affects the harmony and stabilization of the society. Under the background of widely used financial tools to raise leverage these years, we studied the leverage effect on wealth distribution of a population in a controllable laboratory market in which we have conducted several human experiments, and drawn the conclusion that higher leverage leads to a higher Gini coefficient in the market. A higher Gini coefficient means the wealth distribution among a population becomes more unequal. This is a result of the ascending risk with growing leverage level in the market plus the diversified trading abilities and risk preference of the participants. This work sheds light on the effects of leverage and its related regulations, especially its impact on wealth distribution. It also shows the capability of the method of controllable laboratory markets which could be helpful in several fields of study such as economics, econophysics and sociology.

Secondary standards laboratories for ionizing radiation calibrations: the national laboratory interests

International Nuclear Information System (INIS)

Roberson, P.L.; Campbell, G.W.

1984-11-01

The national laboratories are probable candidates to serve as secondary standards laboratories for the federal sector. Representatives of the major Department of Energy laboratories were polled concerning attitudes toward a secondary laboratory structure. Generally, the need for secondary laboratories was recognized and the development of such a program was encouraged. The secondary laboratories should be reviewed and inspected by the National Bureau of Standards. They should offer all of the essential, and preferably additional, calibration services in the field of radiological health protection. The selection of secondary laboratories should be based on economic and geographic criteria and/or be voluntary. 1 ref., 2 tabs

Laboratory Diagnosis of Pertussis

Science.gov (United States)

Schellekens, Joop F. P.; Mooi, Frits R.

2015-01-01

SUMMARY The introduction of vaccination in the 1950s significantly reduced the morbidity and mortality of pertussis. However, since the 1990s, a resurgence of pertussis has been observed in vaccinated populations, and a number of causes have been proposed for this phenomenon, including improved diagnostics, increased awareness, waning immunity, and pathogen adaptation. The resurgence of pertussis highlights the importance of standardized, sensitive, and specific laboratory diagnoses, the lack of which is responsible for the large differences in pertussis notifications between countries. Accurate laboratory diagnosis is also important for distinguishing between the several etiologic agents of pertussis-like diseases, which involve both viruses and bacteria. If pertussis is diagnosed in a timely manner, antibiotic treatment of the patient can mitigate the symptoms and prevent transmission. During an outbreak, timely diagnosis of pertussis allows prophylactic treatment of infants too young to be (fully) vaccinated, for whom pertussis is a severe, sometimes fatal disease. Finally, reliable diagnosis of pertussis is required to reveal trends in the (age-specific) disease incidence, which may point to changes in vaccine efficacy, waning immunity, and the emergence of vaccine-adapted strains. Here we review current approaches to the diagnosis of pertussis and discuss their limitations and strengths. In particular, we emphasize that the optimal diagnostic procedure depends on the stage of the disease, the age of the patient, and the vaccination status of the patient. PMID:26354823

[Biosafety and biosecurity in the medical laboratory. Update and trends].

Science.gov (United States)

Ionescu, G; Neguţ, M; Combiescu, A A

2007-01-01

Biosafety includes the protective measures against the risks of contamination with pathogen germs in the laboratories that handle pathogens, or stock or manipulate potentially contaminated products, or perform microbiological tests for medical or scientific research purposes, as well as the means of protecting the environment and the human collectivities against hazard contaminations that have as starting point these laboratories. Besides, lately, a new notion emerged, that of biosecurity, which refers to the sum of measures designed to protect workers, environment and population against the loss, theft, use and release in the environment of pathogenic biological agents. The work overviews the present concerns for the regulation of these two notions and the way in which a system for the management of the biological risks in a laboratory that handles pathogens should be documented and implemented. The need for the continuous professional training of the staff and for the establishment of individual and collective responsibilities for preventing biosafety incidents and trespassing biosecurity rules are as well emphasized. The main biosafety measures are pointed out and a series of considerations regarding biosafety and bioterrorism in correlation with the medical laboratory are as well mentioned.

Quality management at Argonne National Laboratory: Status, accomplishments, and lessons learned

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-06-01

In April 1992, Argonne National Laboratory (ANL) launched the implementation of quality management (QM) as an initiative of the Laboratory Director. The goal of the program is to seek ways of improving Laboratory performance and effectiveness by drawing from the realm of experiences in the global total quality management movement. The Argonne QM initiative began with fact finding and formulating a strategy for implementation; the emphasis is that the underlying principles of QM should be an integral part of how the Laboratory is managed and operated. A primary theme that has guided the Argonne QM initiative is to consider only those practices that offer the potential for real improvement, make sense, fit the culture, and would be credible to the broad population. In October 1993, the Laboratory began to pilot a targeted set of QM activities selected to produce outcomes important to the Laboratory--strengthening the customer focus, improving work processes, enhancing employee involvement and satisfaction, and institutionalizing QM. This report describes the results of the just-concluded QM development and demonstration phase in terms of detailed strategies, accomplishments, and lessons learned. These results are offered as evidence to support the conclusion that the Argonne QM initiative has achieved value-added results and credibility and is well positioned to support future deployment across the entire Laboratory as an integrated management initiative. Recommendations for follow-on actions to implement future deployment are provided separately.

Aspectos da ecologia e do comportamento de flebotomíneos em área endêmica de leishmaniose visceral, Minas Gerais Aspects of the ecology and behaviour of phlebotomines in endemic area for visceral leishmaniasis in State of Minas Gerais

Directory of Open Access Journals (Sweden)

Ricardo Andrade Barata

2005-10-01

Full Text Available O comportamento e hábitos alimentares de algumas espécies da flebotomíneos têm sido útil na compreensão da epidemiologia das leishmanioses. No município de Porteirinha (MG, foram realizadas capturas mensais sistematizadas utilizando-se 28 armadilhas luminosas tipo CDC, durante o período de janeiro a dezembro de 2002. Foram capturadas 14 espécies de flebotomíneos, totalizando 1.408 exemplares. De acordo com o ambiente, os resultados obtidos mostraram que o peridomicílio apresentou a maior (53,3% porcentagem dos espécimens encontrados na região, embora parte (46,7% da fauna também tenha sido encontrada no intradomicílio. O repasto sanguíneo de 38 fêmeas de Lutzomyia longipalpis, provenientes do campo, foi identificado através da reação de precipitina. Os resultados indicam que Lutzomyia longipalpis foi a espécie predominante (65,1%, mostrando-se oportunista, podendo sugar uma ampla variedade de vertebrados.Studies on the behavioral and feeding habits of some species of phlebotominae sand flies have contributed to the comprehension of the epidemiology of leishmaniasis. In the present work, systematic captures were performed monthly in the municipality of Porteirinha (MG using 28 light traps (CDC from January to December 2002. Fourteen different species of phlebotomine were captured in a total of 1,408 specimens. The highest percentage of individuals (53.3% was collected in the peridomicile against 46.7% in the intradomicile. Lutzomyia longipalpis was the predominant species in that region. The blood feeding of 38 females of this species from the field was analyzed by precipitin reaction. The results indicated that Lutzomyia longipalpis is an opportunist (65.1% species that feeds on a wide variety of vertebrates in nature.

Molecular identification of Lutzomyia migonei (Diptera: Psychodidae) as a potential vector for Leishmania infantum (Kinetoplastida: Trypanosomatidae).

Science.gov (United States)

Rodrigues, Ana Caroline Moura; Melo, Luciana Magalhães; Magalhães, Rafaela Damasceno; de Moraes, Nélio Batista; de Souza Júnior, Antônio Domingos; Bevilaqua, Claudia Maria Leal

2016-04-15

Visceral leishmaniasis (VL) in Brazil is caused by the protozoan Leishmania infantum. This parasite is transmitted by the bite of a female sand fly. The most important sand fly species in VL transmission is Lutzomyia longipalpis. In Fortaleza, the capital of Ceará State, Brazil, the simultaneous occurrence of Lutzomyia migonei and L. longipalpis was detected in localities where VL transmission is observed. The purpose of this study was to determine conclusively if L. migonei can be found naturally infected with L. infantum in key focus in Fortaleza. Using a CDC traps we performed phlebotomine capture during one year. External morphological features and qPCR targeting species-specific gene sequences of Lutzomyia species were used to identify the female phlebotomine sand flies. The molecular identification of the Leishmania species was performed using qPCR targeting species-specific gene sequences of L. infantum and Leishmania braziliensis. The males L. migonei abundance was higher in the rainy season. Humidity and rainfall positively correlated with males L. migonei abundance, while temperature showed a negative correlation. The correlation between the density of L. migonei female with rainfall, relative air humidity, and temperature were not statistically significant. According to the molecular data produced by qPCR amplifications, three positive sand flies were identified as L. longipalpis, and one was identified as L. migonei. The infection rate was 0.35% and 0.18%, respectively. The parasite load was 32,492±2572 L. infantum in L. migonei while the L. longipalpis had parasite loads between 2,444,964.6±116,000 and 6,287,130±124,277. Our findings confirm L. migonei as a potential vector of VL in Fortaleza at a molecular level. Copyright © 2016 Elsevier B.V. All rights reserved.

Mobile spectrometric laboratory

International Nuclear Information System (INIS)

Isajenko, K.A.; Lipinski, P.

2002-01-01

The article presents the Mobile Spectrometric Laboratory used by Central Laboratory for Radiological Protection since year 2000. The equipment installed in the Mobile Laboratory and its uses is described. The results of international exercises and intercalibrations, in which the Laboratory participated are presented. (author)

75 FR 34463 - Oversight of Laboratory Developed Tests; Public Meeting; Request for Comments

Science.gov (United States)

2010-06-17

... patient population. In addition, the components of traditional LDTs were regulated individually by FDA as... field creates a competitive disadvantage and potential disincentive to innovation by other manufacturers...) Challenges for Laboratories, (3) Direct to Consumer Marketing of Testing, and (4) Education and Outreach...

Research programs at the Department of Energy National Laboratories. Volume 2: Laboratory matrix

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-01

For nearly fifty years, the US national laboratories, under the direction of the Department of Energy, have maintained a tradition of outstanding scientific research and innovative technological development. With the end of the Cold War, their roles have undergone profound changes. Although many of their original priorities remain--stewardship of the nation`s nuclear stockpile, for example--pressing budget constraints and new federal mandates have altered their focus. Promotion of energy efficiency, environmental restoration, human health, and technology partnerships with the goal of enhancing US economic and technological competitiveness are key new priorities. The multiprogram national laboratories offer unparalleled expertise in meeting the challenge of changing priorities. This volume aims to demonstrate each laboratory`s uniqueness in applying this expertise. It describes the laboratories` activities in eleven broad areas of research that most or all share in common. Each section of this volume is devoted to a single laboratory. Those included are: Argonne National Laboratory; Brookhaven National Laboratory; Idaho National Engineering Laboratory; Lawrence Berkeley Laboratory; Lawrence Livermore National Laboratory; Los Alamos National Laboratory; National Renewable Energy Laboratory; Oak Ridge National Laboratory; Pacific Northwest Laboratory; and Sandia National Laboratories. The information in this volume was provided by the multiprogram national laboratories and compiled at Lawrence Berkeley Laboratory.

Public census data on CD-ROM at Lawrence Berkeley Laboratory

Energy Technology Data Exchange (ETDEWEB)

Merrill, D.W.

1992-07-02

In connection with the Comprehensive Epidemiologic Data Resource (CEDR) and Populations at Risk to Environmental Pollution (PAREP) projects, of the Information and Computing Sciences Division (ICSD) at Lawrence Berkeley Laboratory (LBL), are using public socioeconomic and geographic data files which are available to CEDR and PAREP collaborators via LBL's computing network. At this time 67 CD-ROM diskettes (approximately 35 gigabytes) are on line via the Unix file server cedrcd.lbl.gov. Most of the files are from the US Bureau of the Census, and most pertain to the 1990 Census of Population and Housing. This paper contains a list of the CD-ROMs available.

1986 environmental monitoring program report for the Idaho National Engineering Laboratory Site

International Nuclear Information System (INIS)

Hoff, D.L.; Chew, E.W.; Rope, S.K.

1987-05-01

This report presents onsite and offsite data collected in 1986 for the routine environmental monitoring program conducted by the Radiological and Environmental Sciences Laboratory (RESL) of the Department of Energy (DOE) at the Idaho National Engineering Laboratory (INEL) Site. The purpose of this routine program is to monitor radioactive and nonradioactive materials resulting from INEL Site operations which may reach the surrounding offsite environment and population. This report is prepared in accordance with the DOE requirements in draft DOE Order 5484.1 and is not intended to cover the numerous special environmental research programs being conducted at the INEL by RESL and others

Nanotechnology Characterization Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Nanotechnology Characterization Laboratory (NCL) at the Frederick National Laboratory for Cancer Research performs preclinical characterization of nanomaterials...

Semiconductor Electrical Measurements Laboratory

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Federal Laboratory Consortium — The Semiconductor Electrical Measurements Laboratory is a research laboratory which complements the Optical Measurements Laboratory. The laboratory provides for Hall...

Argonne National Laboratory-East site environmental report for calendar year 1995

Energy Technology Data Exchange (ETDEWEB)

Golchert, N.W.; Kolzow, R.G. [Environmental Management Operation, Argonne National Lab., IL (United States)

1996-09-01

This report presents the environmental report for the Argonne National Laboratory-East for the year of 1995. Topics discussed include: general description of the site including climatology, geology, seismicity, hydrology, vegetation, endangered species, population, water and land use, and archaeology; compliance summary; environmental program information; environmental nonradiological program information; ground water protection; and radiological monitoring program.

POLLUTION PREVENTION OPPORTUNITY ASSESSMENT - GEOCHEMISTRY LABORATORY AT SANDIA NATIONAL LABORATORIES

Science.gov (United States)

These reports summarize pollution prevention opportunity assessments conducted jointly by EPA and DOE at the Geochemistry Laboratory and the Manufacturing and Fabrication Repair Laboratory at the Department of Energy's Sandia National Laboratories facility in Albuquerque, New Mex...

Bio Engineering Laboratory

Data.gov (United States)

Federal Laboratory Consortium — Description/History: Chemistry and biology laboratoriesThe Bio Engineering Laboratory (BeL) is theonly full spectrum biotechnology capability within the Department...

Population genomics of parallel adaptation in threespine stickleback using sequenced RAD tags.

Directory of Open Access Journals (Sweden)

Paul A Hohenlohe

2010-02-01

Full Text Available Next-generation sequencing technology provides novel opportunities for gathering genome-scale sequence data in natural populations, laying the empirical foundation for the evolving field of population genomics. Here we conducted a genome scan of nucleotide diversity and differentiation in natural populations of threespine stickleback (Gasterosteus aculeatus. We used Illumina-sequenced RAD tags to identify and type over 45,000 single nucleotide polymorphisms (SNPs in each of 100 individuals from two oceanic and three freshwater populations. Overall estimates of genetic diversity and differentiation among populations confirm the biogeographic hypothesis that large panmictic oceanic populations have repeatedly given rise to phenotypically divergent freshwater populations. Genomic regions exhibiting signatures of both balancing and divergent selection were remarkably consistent across multiple, independently derived populations, indicating that replicate parallel phenotypic evolution in stickleback may be occurring through extensive, parallel genetic evolution at a genome-wide scale. Some of these genomic regions co-localize with previously identified QTL for stickleback phenotypic variation identified using laboratory mapping crosses. In addition, we have identified several novel regions showing parallel differentiation across independent populations. Annotation of these regions revealed numerous genes that are candidates for stickleback phenotypic evolution and will form the basis of future genetic analyses in this and other organisms. This study represents the first high-density SNP-based genome scan of genetic diversity and differentiation for populations of threespine stickleback in the wild. These data illustrate the complementary nature of laboratory crosses and population genomic scans by confirming the adaptive significance of previously identified genomic regions, elucidating the particular evolutionary and demographic history of such

Measurements of benzene and formaldehyde in a medium sized urban environment. Indoor/outdoor health risk implications on special population groups.

Science.gov (United States)

Pilidis, Georgios A; Karakitsios, Spyros P; Kassomenos, Pavlos A; Kazos, Elias A; Stalikas, Constantine D

2009-03-01

In the present study, the results of a measurement campaign aiming to assess cancer risk among two special groups of population: policemen and laboratory technicians exposed to the toxic substances, benzene and formaldehyde are presented. The exposure is compared to general population risk. The results show that policemen working outdoor (traffic regulation, patrol on foot or in vehicles, etc.) are exposed at a significantly higher benzene concentration (3-5 times) than the general population, while the exposure to carbonyls is in general lower. The laboratory technicians appear to be highly exposed to formaldehyde while no significant variation of benzene exposure in comparison to the general population is recorded. The assessment revealed that laboratory technicians and policemen run a 20% and 1% higher cancer risk respectively compared to the general population. Indoor working place air quality is more significant in assessing cancer risk in these two categories of professionals, due to the higher Inhalation Unit Risk (IUR) of formaldehyde compared to benzene. Since the origin of the danger to laboratory technicians is clear (use of chemicals necessary for the experiments), in policemen the presence of carbonyls in indoor air concentrations due to smoking or used materials constitute a danger equal to the exposure to traffic originated air pollutants.

Advanced Chemistry Laboratory

Data.gov (United States)

Federal Laboratory Consortium — Description/History: Chemistry laboratoryThe Advanced Chemistry Laboratory (ACL) is a unique facility designed for working with the most super toxic compounds known...

FOOTWEAR PERFORMANCE LABORATORY

Data.gov (United States)

Federal Laboratory Consortium — This laboratory provides biomechanical and physical analyses for both military and commercial footwear. The laboratory contains equipment that is integral to the us...

Natural populations of drosophila melanogaster from radioactively contaminated territories of Ukraine

International Nuclear Information System (INIS)

Protsenko, A.V.; Kozeretskaya, I.A.

2007-01-01

Complete text of publication follows. Drosophila melanogaster has been used as a model object to study Chernobyl NPP after-effects on biological processes. We performed study of natural populations from sites contaminated with radionuclides. Drosophila individuals were collected in autumn 2005 and 2006 in the regions with different degrees of radioactive contamination. The flies were sampled in Polesskoe with radioactive background of 50 uR/h; near cooling pond of Chernobyl NPP (2100 uR/h); Chernobyl city (60 uR/h); Kyiv (17 uR/h), Lubny (16 uR/h); Piryatin (15 uR/h); Uman (12 uR/h); Odessa (13 uR/h). Hybridological analysis was performed using drosophila laboratory lines Canton S (wild type strain) and C(1)DX (to detect lethal mutations in sex chromosome). The flies were kept on a standard medium in laboratory conditions. Occurrence of hybrid dysgenesis was monitored by gonad reduction, isolating the gonads and evaluating visually the degree of their development. Visual mutations have not been found in all the natural populations studied. When the populations were transferred to culture breeding, an elevation of the mutation visible frequency in generations has been detected. The elevation was the highest for Chernobyl (2100 uR/h) population. All the mutations observed are typical for Ukraine. Low frequency of gonad reduction has been detected. Since the gonad reduction is one of the traits of mobile elements activity in drosophilids, a conclusion has been made about the absence of mobile elements activity in all the populations, including the laboratory wild-type line Canton S. The results of the gonad reduction analysis indirectly confirm the low frequency of visual mutations in the populations studied. To assess the spontaneous level of lethal sex-linked mutations, the male/female ratio was evaluated in the first generation and compared with the ratio in the strain Canton S (using as control) using χ2-criterion. In natural populations from Lubny and Piryatin

Lincoln Laboratory Grid

Data.gov (United States)

Federal Laboratory Consortium — The Lincoln Laboratory Grid (LLGrid) is an interactive, on-demand parallel computing system that uses a large computing cluster to enable Laboratory researchers to...

Photometrics Laboratory

Data.gov (United States)

Federal Laboratory Consortium — Purpose:The Photometrics Laboratory provides the capability to measure, analyze and characterize radiometric and photometric properties of light sources and filters,...

Blackroom Laboratory

Data.gov (United States)

Federal Laboratory Consortium — FUNCTION: Enables evaluation and characterization of materials ranging from the ultraviolet to the longwave infrared (LWIR).DESCRIPTION: The Blackroom Laboratory is...

Natural occurrence of baculoviruses in populations of some Heliconiini (Lepidoptera; Nymphalidae with symptomatological notes

Directory of Open Access Journals (Sweden)

G. F. S. Andrade

1983-01-01

Full Text Available Natural occurrence of nuclear polyhedrosis viruses were detected in populations of some Heliconiini in the field as well as in the laboratory. The epizootics appeared under field conditions in populations of Dione juno juno, D. moneta and Agraulis vanillae maculosa. In the laboratory, however, larvae of Heliconius numata mirus, H. hecale vetustus and H. erato phyllis in addition to two hybrids and Eueides Isabella dianasa, all suffered the same disease. The effect of several factors which might contribute to the occurrence of the disease are discussed. Symptoms, histopathology and description of viral particles and polyhedra are given.

Laboratory Building

Energy Technology Data Exchange (ETDEWEB)

Herrera, Joshua M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-03-01

This report is an analysis of the means of egress and life safety requirements for the laboratory building. The building is located at Sandia National Laboratories (SNL) in Albuquerque, NM. The report includes a prescriptive-based analysis as well as a performance-based analysis. Following the analysis are appendices which contain maps of the laboratory building used throughout the analysis. The top of all the maps is assumed to be north.

Knowledge and practices of pharmaceutical laboratory workers on laboratory safety

Directory of Open Access Journals (Sweden)

Esra Emerce

2017-09-01

Full Text Available Laboratories are classified as very hazardous workplaces. Objective: The aim of this descriptive study was to determine the knowledge and practice of laboratory safety by analysts and technicians in the laboratories of the Turkish Medicine and Medical Devices Agency. Methods:  85.0% (n=93 of the workers (n=109 was reached. A pre-tested, laboratory safety oriented, self-administered questionnaire was completed under observation. Results: Participants were mostly female (66,7%, had 12.8±8.2 years of laboratory experience and worked 24.6±10.3 hours per week. 53.8% of the employees generally worked with flammable and explosive substances, 29.0% with acute toxic or carcinogenic chemicals and 30.1% with physical dangers. Of all surveyed, 14.0% had never received formal training on laboratory safety. The proportion of ‘always use’ of laboratory coats, gloves, and goggles were 84.9%, 66.7%, and 6.5% respectively. 11.9% of the participants had at least one serious injury throughout their working lives and 24.7% had at least one small injury within the last 6 months. Among these injuries, incisions, bites and tears requiring no stiches (21.0% and the inhalation of chemical vapors (16.1% took first place. The mean value for the number of correct responses to questions on basic safety knowledge was 65.4±26.5, out of a possible 100. Conclusion: Overall, the participants have failed in some safety practices and have been eager to get regular education on laboratory safety.  From this point onwards, it would be appropriate for the employers to organize periodic trainings on laboratory safety.Keywords: Health personnel, laboratory personnel, occupational health, occupational safety, pharmacy

Radioactive wastes: underground laboratories implantation

International Nuclear Information System (INIS)

Bataille, Ch.

1997-01-01

This article studies the situation of radioactive waste management, more especially the possible storage in deep laboratories. In front of the reaction of public opinion relative to the nuclear waste question, it was essential to begin by a study on the notions of liability, transparence and democracy. At the beginning, it was a matter of underground researches with a view to doing an eventual storage of high level radioactive wastes. The Parliament had to define, through the law, a behaviour able to come to the fore for anybody. A behaviour which won recognition from authorities, from scientists, from industrial people, which guarantees the rights of populations confronted to a problem whom they were not informed, on which they received only few explanations. (N.C.)

Nature beats nurture: a case study of the physiological fitness of free-living and laboratory-reared male Anopheles gambiae s.l.

NARCIS (Netherlands)

Hubo, B.J.; Ng'habi, K.R.; Killeen, G.F.; Nkwengulila, G.; Knols, B.G.J.; Ferguson, H.M.

2007-01-01

Laboratory experimentation forms the basis for most of our knowledge of the biology of many organisms, in particular insects. However, the accuracy with which laboratory-derived estimates of insect life history and behaviour can predict their fitness and population dynamics in the wild is rarely

The Cost-Effective Laboratory: Implementation of Economic Evaluation of Laboratory Testing

Directory of Open Access Journals (Sweden)

Bogavac-Stanojevic Natasa

2017-09-01

Full Text Available Laboratory testing as a part of laboratory in vitro diagnostic (IVD has become required tool in clinical practice for diagnosing, monitoring and prognosis of diseases, as well as for prediction of treatment response. The number of IVD tests available in laboratory practice has increased over the past decades and is likely to further increase in the future. Consequently, there is growing concern about the overutilization of laboratory tests and rising costs for laboratory testing. It is estimated that IVD accounts for between 1.4 and 2.3% of total healthcare expenditure and less than 5% of total hospital cost (Lewin Group report. These costs are rather low when compared to pharmaceuticals and medical aids which account for 15 and 5%, respectively. On the other hand, IVD tests play an important role in clinical practice, as they influence from 60% to 70% of clinical decision-making. Unfortunately, constant increases in healthcare spending are not directly related to healthcare benefit. Since healthcare resources are limited, health payers are interested whether the benefits of IVD tests are actually worth their cost. Many articles have introduced frameworks to assess the economic value of IVD tests. The most appropriate tool for quantitative assessment of their economic value is cost-effectiveness (CEA and cost-utility (CUA analysis. The both analysis determine cost in terms of effectiveness or utilities (combine quantity and quality of life of new laboratory test against its alternative. On the other hand, some investigators recommended calculation of laboratory test value as product of two ratios: Laboratory test value = (Technical accuracy/Turnaround time × (Utility/Costs. Recently, some researches used multicriteria decision analysis which allows comparison of diagnostic strategies in terms of benefits, opportunities, costs and risks. All analyses are constructed to identify laboratory test that produce the greatest healthcare benefit with

Virtual Laboratory "vs." Traditional Laboratory: Which Is More Effective for Teaching Electrochemistry?

Science.gov (United States)

Hawkins, Ian; Phelps, Amy J.

2013-01-01

The use of virtual laboratories has become an increasing issue regarding science laboratories due to the increasing cost of hands-on laboratories, and the increase in distance education. Recent studies have looked at the use of virtual tools for laboratory to be used as supplements to the regular hands-on laboratories but many virtual tools have…

The first canine visceral leishmaniasis outbreak in Campinas, State of São Paulo Southeastern Brazil

Directory of Open Access Journals (Sweden)

Andrea Paula Bruno von Zuben

2014-06-01

Full Text Available Introduction Early detection of American visceral leishmaniasis (AVL outbreak in animals is crucial for controlling this disease in non-endemic areas. Methods Epidemiological surveillance (2009-2012 was performed in Campinas, State of São Paulo, Brazil. Results In 2009, Leishmania chagasi was positively identified in four dogs. Entomological research and three serological studies (2010-2012 were undertaken as monitoring measures; these approaches revealed a moderate prevalence of Leishmania present in 4% of the canine population. Nyssomyia whitmani and Lutzomyia longipalpis were the predominant species identified. Conclusions Detection of an AVL outbreak in dogs in an area with an evolving natural landscape containing sand flies is crucial for control programs.

Routine internal- and external-quality control data in clinical laboratories for estimating measurement and diagnostic uncertainty using GUM principles.

Science.gov (United States)

Magnusson, Bertil; Ossowicki, Haakan; Rienitz, Olaf; Theodorsson, Elvar

2012-05-01

Healthcare laboratories are increasingly joining into larger laboratory organizations encompassing several physical laboratories. This caters for important new opportunities for re-defining the concept of a 'laboratory' to encompass all laboratories and measurement methods measuring the same measurand for a population of patients. In order to make measurement results, comparable bias should be minimized or eliminated and measurement uncertainty properly evaluated for all methods used for a particular patient population. The measurement as well as diagnostic uncertainty can be evaluated from internal and external quality control results using GUM principles. In this paper the uncertainty evaluations are described in detail using only two main components, within-laboratory reproducibility and uncertainty of the bias component according to a Nordtest guideline. The evaluation is exemplified for the determination of creatinine in serum for a conglomerate of laboratories both expressed in absolute units (μmol/L) and relative (%). An expanded measurement uncertainty of 12 μmol/L associated with concentrations of creatinine below 120 μmol/L and of 10% associated with concentrations above 120 μmol/L was estimated. The diagnostic uncertainty encompasses both measurement uncertainty and biological variation, and can be estimated for a single value and for a difference. This diagnostic uncertainty for the difference for two samples from the same patient was determined to be 14 μmol/L associated with concentrations of creatinine below 100 μmol/L and 14 % associated with concentrations above 100 μmol/L.

Gun Dynamics Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Gun Dynamics Laboratory is a research multi-task facility, which includes two firing bays, a high bay area and a second floor laboratory space. The high bay area...

Ecological interactions affecting population-level responses to chemical stress in Mesocyclops leuckarti.

Science.gov (United States)

Kulkarni, Devdutt; Hommen, Udo; Schäffer, Andreas; Preuss, Thomas G

2014-10-01

Higher tiers of ecological risk assessment (ERA) consider population and community-level endpoints. At the population level, the phenomenon of density dependence is one of the most important ecological processes that influence population dynamics. In this study, we investigated how different mechanisms of density dependence would influence population-level ERA of the cyclopoid copepod Mesocyclops leuckarti under toxicant exposure. We used a combined approach of laboratory experiments and individual-based modelling. An individual-based model was developed for M. leuckarti to simulate population dynamics under triphenyltin exposure based on individual-level ecological and toxicological data from laboratory experiments. The study primarily aimed to-(1) determine which life-cycle processes, based on feeding strategies, are most significant in determining density dependence (2) explore how these mechanisms of density dependence affect extrapolation from individual-level effects to the population level under toxicant exposure. Model simulations showed that cannibalism of nauplii that were already stressed by TPT exposure contributed to synergistic effects of biotic and abiotic factors and led to a twofold stress being exerted on the nauplii, thereby resulting in a higher population vulnerability compared to the scenario without cannibalism. Our results suggest that in population-level risk assessment, it is easy to underestimate toxicity unless underlying ecological interactions including mechanisms of population-level density regulation are considered. This study is an example of how a combined approach of experiments and mechanistic modelling can lead to a thorough understanding of ecological processes in ecotoxicology and enable a more realistic ERA. Copyright © 2014 Elsevier Ltd. All rights reserved.

Computational Laboratory

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Federal Laboratory Consortium — This laboratory contains a number of commercial off-the-shelf and in-house software packages allowing for both statistical analysis as well as mathematical modeling...

Laboratory hemostasis: milestones in Clinical Chemistry and Laboratory Medicine.

Science.gov (United States)

Lippi, Giuseppe; Favaloro, Emmanuel J

2013-01-01

Hemostasis is a delicate, dynamic and intricate system, in which pro- and anti-coagulant forces cooperate for either maintaining blood fluidity under normal conditions, or else will prompt blood clot generation to limit the bleeding when the integrity of blood vessels is jeopardized. Excessive prevalence of anticoagulant forces leads to hemorrhage, whereas excessive activation of procoagulant forces triggers excessive coagulation and thrombosis. The hemostasis laboratory performs a variety of first, second and third line tests, and plays a pivotal role in diagnostic and monitoring of most hemostasis disturbances. Since the leading targets of Clinical Chemistry and Laboratory Medicine include promotion of progress in fundamental and applied research, along with publication of guidelines and recommendations in laboratory diagnostics, this journal is an ideal source of information on current developments in the laboratory technology of hemostasis, and this article is aimed to celebrate some of the most important and popular articles ever published by the journal in the filed of laboratory hemostasis.

Geomechanics Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Geomechanics Laboratory allows its users to measure rock properties under a wide range of simulated service conditions up to very high pressures and complex load...

Assessing sexual conflict in the Drosophila melanogaster laboratory model system

Science.gov (United States)

Rice, William R; Stewart, Andrew D; Morrow, Edward H; Linder, Jodell E; Orteiza, Nicole; Byrne, Phillip G

2006-01-01

We describe a graphical model of interlocus coevolution used to distinguish between the interlocus sexual conflict that leads to sexually antagonistic coevolution, and the intrinsic conflict over mating rate that is an integral part of traditional models of sexual selection. We next distinguish the ‘laboratory island’ approach from the study of both inbred lines and laboratory populations that are newly derived from nature, discuss why we consider it to be one of the most fitting forms of laboratory analysis to study interlocus sexual conflict, and then describe four experiments using this approach with Drosophila melanogaster. The first experiment evaluates the efficacy of the laboratory model system to study interlocus sexual conflict by comparing remating rates of females when they are, or are not, provided with a spatial refuge from persistent male courtship. The second experiment tests for a lag-load in males that is due to adaptations that have accumulated in females, which diminish male-induced harm while simultaneously interfering with a male's ability to compete in the context of sexual selection. The third and fourth experiments test for a lag-load in females owing to direct costs from their interactions with males, and for the capacity for indirect benefits to compensate for these direct costs. PMID:16612888

Overview and challenges of molecular technologies in the veterinary microbiology laboratory.

Science.gov (United States)

Cunha, Mónica V; Inácio, João

2015-01-01

Terrestrial, aquatic, and aerial animals, either domestic or wild, humans, and plants all face similar health threats caused by infectious agents. Multifaceted anthropic pressure caused by an increasingly growing and resource-demanding human population has affected biodiversity at all scales, from the DNA molecule to the pathogen, to the ecosystem level, leading to species declines and extinctions and, also, to host-pathogen coevolution processes. Technological developments over the last century have also led to quantic jumps in laboratorial testing that have highly impacted animal health and welfare, ameliorated animal management and animal trade, safeguarded public health, and ultimately helped to "secure" biodiversity. In particular, the field of molecular diagnostics experienced tremendous technical progresses over the last two decades that significantly have contributed to our ability to study microbial pathogens in the clinical and research laboratories. This chapter highlights the strengths, weaknesses, opportunities, and threats (or challenges) of molecular technologies in the framework of a veterinary microbiology laboratory, in view of the latest advances.

Psychosocial and individual characteristics and musculoskeletal complaints among clinical laboratory workers.

Science.gov (United States)

Sadeghian, Farideh; Kasaeian, Amir; Noroozi, Pirasteh; Vatani, Javad; Taiebi, Seiyed Hassan

2014-01-01

Musculoskeletal disorders (MSDs) are an important health problem among healthcare workers, including clinical laboratory ones. The aim of the present study was to investigate the prevalence of MSDs and individual and psychosocial risk factors among clinical laboratory workers. A cross-sectional study was carried out among 156 workers of 30 clinical laboratories in 3 towns of Iran. The Nordic questionnaire with individual and psychosocial risk factors was used to collect data. Multiple logistic regression analysis was performed. The prevalence of reported MSDs among the study population was 72.4% in the past 12 months. The most prevalent MSDs were pain in the lower back and neck; 42.7% and 33.3%, respectively. Significant relations were found between MSDs and age, gender, heavy work at home and job control (p workers were high and associated with age, gender, heavy work at home and job control. More research into measuring these factors and workplace physical demands is suggested.

Hyperthermia: from the clinic to the laboratory and back again

International Nuclear Information System (INIS)

Maher, E.J.

1989-01-01

Murine tumours have been used extensively to investigate the effects of heat and radiation, but there are significant differences between controlled laboratory studies and relatively uncontrolled clinical experience. From 1983 to 1986 a simple clinical system was developed in order to investigate biological questions in the clinic. This involved identifying a suitable patient population, reliable heating and thermometry, and methods of evaluating response of human tumours and their vasculature. (author)

The biochemical estimation of age in Euphausiids: Laboratory calibration and field comparisons

Science.gov (United States)

Harvey, H. R.; Ju, Se-J.; Son, S.-K.; Feinberg, L. R.; Shaw, C. T.; Peterson, W. T.

2010-04-01

Euphausiids play a key role in many marine ecosystems as a link between primary producers and top predators. Understanding their demographic (i.e. age) structure is an essential tool to assess growth and recruitment as well as to determine how changes in environmental conditions might alter their condition and distribution. Age determination of crustaceans cannot be accomplished using traditional approaches, and here we evaluate the potential for biochemical products of tissue metabolism (termed lipofuscins) to determine the demographic structure of euphausiids in field collections . Lipofuscin was extracted from krill neural tissues (eye and eye-stalk), quantified using fluorescent intensity and normalized to tissue protein content to allow comparisons across animal sizes. Multiple fluorescent components from krill were observed, with the major product having a maximum fluorescence at excitation of 355 nm and emission of 510 nm. Needed age calibration of lipofuscin accumulation in Euphausia pacifica was accomplished using known-age individuals hatched and reared in the laboratory for over one year. Lipofuscin content extracted from neural tissues of laboratory-reared animals was highly correlated with the chronological age of animals ( r=0.87). Calibrated with laboratory lipofuscin accumulation rates, field-collected sub-adult and adult E. pacifica in the Northeast Pacific were estimated to be older than 100 days and younger than 1year. Comparative data for the Antarctic krill, E. superba showed much higher lipofuscin values suggesting a much longer lifespan than the more temperate species, E. pacifica. These regional comparisons suggest that biochemical indices allow a practical approach to estimate population age structure of diverse populations, and combined with other measurements can provide estimates of vital rates (i.e. longevity, mortality, growth) for krill populations in dynamic environments.

Saxton Transportation Operations Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Saxton Transportation Operations Laboratory (Saxton Laboratory) is a state-of-the-art facility for conducting transportation operations research. The laboratory...

THE METHODS OF LABORATORY DIAGNOSTICS OF UROGENITAL INFECTIONS ASSOCIATED WITH MYCOPLASMA HOMINIS AND UREAPLASMA SPP.

Directory of Open Access Journals (Sweden)

O. V. Zarucheynova

2014-01-01

Full Text Available Wide distribution of urogenital mycoplasmas in the population, the high frequency of carrier state and a long asymptomatic course of disease, the lack of specific clinical symptoms making the diagnosis impossible without using of special laboratory tests. The review focuses on indications for mycoplasma infection screening and for an appointmentof antibiotic therapy. The most commonly used laboratory diagnostic methods of urogenital infections, associated with Mycoplasma hominis and Ureaplasma spp., with their characteristics, advantages and disadvantages are described.

The European network of Biosafety-Level-4 laboratories: enhancing European preparedness for new health threats.

Science.gov (United States)

Nisii, C; Castilletti, C; Di Caro, A; Capobianchi, M R; Brown, D; Lloyd, G; Gunther, S; Lundkvist, A; Pletschette, M; Ippolito, G

2009-08-01

Emerging and re-emerging infections and possible bioterrorism acts will continue to challenge both the medical community and civilian populations worldwide, urging health authorities to respond rapidly and effectively. Established in 2005, the European Community (EC)-funded European Network of Biosafety-Level-4 laboratories (Euronet-P4), which brings together the laboratories in Porton Down, London, Hamburg, Marburg, Solna, Lyon and Rome, seeks to increase international collaboration in the areas of high containment laboratory biosafety and viral diagnostic capability, to strengthen Europe's capacity to respond to an infectious disease emergency, and to offer assistance to countries not equipped with such costly facilities. Network partners have agreed on a common strategy to fill the gaps identified in the field of risk group-4 agents' laboratory diagnosis, namely the lack of standardization and of reference samples. The network has received a further 3-year funding, to offer assistance to external laboratories, and to start the planning of field activities.

Role of population genetics in the sterile insect technique

International Nuclear Information System (INIS)

Krafsur, E.S.

2005-01-01

The detection and analysis of genetic variation in natural and laboratory populations are reviewed. The application of population genetic methods and theory can help to plan and evaluate the implementation of area-wide integrated pest management (AW-IPM) programmes that use the sterile insect technique (SIT). Population genetic studies can play an important role in estimating dispersal rates and thus gene flow among target populations, determining if sibling species exist, establishing the origin of outbreaks or reintroductions, and supporting the quality control of mass-reared colonies. The target's population history may be examined, in terms of 'bottlenecks', range fragmentations, and expansions. Genetic methods can be helpful in distinguishing wild insects from released sterile or substerile ones, and in ascertaining, together with mating cross-compatibility studies, the compatibility of mass-reared colonies with target wild insects. (author)

[Future roles of clinical laboratories and clinical laboratory technologists in university hospitals].

Science.gov (United States)

Yokota, Hiromitsu; Yatomi, Yutaka

2013-08-01

Clinical laboratories in university hospitals should be operated with a good balance of medical practice, education, research, and management. The role of a clinical laboratory is to promptly provide highly reliable laboratory data to satisfy the needs of clinicians involved in medical practice and health maintenance of patients. Improvement and maintenance of the quality of the laboratory staff and environment are essential to achieve this goal. In order to implement these requirements efficiently, an appropriate quality management system should be introduced and established, and evaluated objectively by a third party (e.g. by obtaining ISO 15189 certification). ISO 15189 is an international standard regarding the quality and competence of clinical laboratories, and specifies a review of the efficient operational system and technical requirements such as competence in implementing practical tests and calibration. This means the results of laboratory tests reported by accredited laboratories withstand any international evaluation, which is very important to assure the future importance of the existence and management of clinical laboratories as well as internationalization of medical practice. "Education" and "research" have important implications in addition to "medical practice" and "management", as the roles that clinical laboratories should play in university hospitals. University hospital laboratories should be operated by keeping these four factors in good balance. Why are "education" and "research" required in addition to "medical practice" services? If individual clinical laboratory technologists can provide an appropriate response to this question, the importance of the existence of clinical laboratories would be reinforced, without being compromised.

Tritium Research Laboratory safety analysis report

Energy Technology Data Exchange (ETDEWEB)

Wright, D.A.

1979-03-01

Design and operational philosophy has been evolved to keep radiation exposures to personnel and radiation releases to the environment as low as reasonably achievable. Each experiment will be doubly contained in a glove box and will be limited to 10 grams of tritium gas. Specially designed solid-hydride storage beds may be used to store temporarily up to 25 grams of tritium in the form of tritides. To evaluate possible risks to the public or the environment, a review of the Sandia Laboratories Livermore (SLL) site was carried out. Considered were location, population, land use, meteorology, hydrology, geology, and seismology. The risks and the extent of damage to the TRL and vital systems were evaluated for flooding, lightning, severe winds, earthquakes, explosions, and fires. All of the natural phenomena and human error accidents were considered credible, although the extent of potential damage varied. However, rather than address the myriad of specific individual consequences of each accident scenario, a worst-case tritium release caused indirectly by an unspecified natural phenomenon or human error was evaluated. The maximum credible radiological accident is postulated to result from the release of the maximum quantity of gas from one experiment. Thus 10 grams of tritium gas was used in the analysis to conservatively estimate the maximum whole-body dose of 1 rem at the site boundary and a maximum population dose of 600 man-rem. Accidental release of this amount of tritium implies simultaneous failure of two doubly contained systems, an occurrence considered not credible. Nuclear criticality is impossible in this facility. Based upon the analyses performed for this report, we conclude that the Tritium Research Laboratory can be operated without undue risk to employees, the general public, or the environment. (ERB)

Tritium Research Laboratory safety analysis report

International Nuclear Information System (INIS)

Wright, D.A.

1979-03-01

Design and operational philosophy has been evolved to keep radiation exposures to personnel and radiation releases to the environment as low as reasonably achievable. Each experiment will be doubly contained in a glove box and will be limited to 10 grams of tritium gas. Specially designed solid-hydride storage beds may be used to store temporarily up to 25 grams of tritium in the form of tritides. To evaluate possible risks to the public or the environment, a review of the Sandia Laboratories Livermore (SLL) site was carried out. Considered were location, population, land use, meteorology, hydrology, geology, and seismology. The risks and the extent of damage to the TRL and vital systems were evaluated for flooding, lightning, severe winds, earthquakes, explosions, and fires. All of the natural phenomena and human error accidents were considered credible, although the extent of potential damage varied. However, rather than address the myriad of specific individual consequences of each accident scenario, a worst-case tritium release caused indirectly by an unspecified natural phenomenon or human error was evaluated. The maximum credible radiological accident is postulated to result from the release of the maximum quantity of gas from one experiment. Thus 10 grams of tritium gas was used in the analysis to conservatively estimate the maximum whole-body dose of 1 rem at the site boundary and a maximum population dose of 600 man-rem. Accidental release of this amount of tritium implies simultaneous failure of two doubly contained systems, an occurrence considered not credible. Nuclear criticality is impossible in this facility. Based upon the analyses performed for this report, we conclude that the Tritium Research Laboratory can be operated without undue risk to employees, the general public, or the environment

Case study: improving efficiency in a large hospital laboratory.

Science.gov (United States)

Bartel, Marilynn

2004-01-01

Saint Francis Health System (SFHS) consists of three hospitals and one clinic: Saint Francis Hospital (SFH); Broken Arrow Medical Center; Laureate Psychiatric Hospital; and Warren Clinic. SFHS has 670 physicians on staff and serves medical (oncology, orthopedic, neurology, and renal), surgical, cardiac, women and infant, pediatric, transplant, and trauma patients in Tulsa County, Oklahoma, which has a population of 660,000. SFH incorporates 706 staffed beds, including 126 pediatric beds and 119 critical care beds. Each year, the health system averages 38,000 admissions, 70,000 emergency department visits, 25,000 surgeries, and 3,500 births. Saint Francis Laboratory is located within the main hospital facility (SFH) and functions as a core lab for the health system. The lab also coordinates lab services with Saint Francis Heart Hospital, a physician-system joint venture. The Optimal Equipment Configuration (OEC) Project was designed by the Clinical Laboratory Services division of Premier, a group purchasing organization, with the goal of determining whether laboratories could improve efficiency and decrease unit cost by using a single-source vendor. Participants included seven business partners (Abbott, Bayer, Beckman/Coulter, Dade/Behring, J&J/ Ortho, Olympus, and Roche) and 21 laboratory sites (a small, mid-sized, and large site for each vendor). SFH laboratory staff embraced Premier's concept and viewed the OEC project as an opportunity to "energize" laboratory operations. SFH partnered with Abbott, their primary equipment vendor, for the project. Using resources and tools made available through the project, the laboratory was re-engineered to simplify workflow, increase productivity, and decrease costs by adding automation and changing to centralized specimen processing. Abbott and SFH shared a common vision for the project and enhanced their partnership through increased communication and problem solving. Abbott's area representatives provided for third

Organization of measures on protection of population and territories against weapons of mass destruction: brief analysis of laboratory control and conditions of personnel protective means of respiratory organs in the Republic of Tajikistan

International Nuclear Information System (INIS)

Kamalov, D.D.; Makhmadov, T.F.; Stotskiy, D.F.

2010-01-01

and territory protection from mass-destruction weapon. Organization of actions on population and territory protection is caused on geographical location of Tajikistan. There is a number of some states near Tajikistan that have nuclear weapon: India, China, Pakistan. The basic actions for protection of the population and territories from weapons of mass destruction are: maintenance and accumulation of means of an individual defense, creation of stocks; creation and restoration of protective constructions of a civil defense; evacuation actions planning; restoration of system of monitoring and the laboratory control of a civil defense of Republic Tajikistan; according to the Government Regulation N 527 and dated on 31"s"t of October, 2008 the 'Emergency situations and civil defense system development 2009-2014' Program was adopted. According to the Plan of the events within this Programme Committee of emergency situations and civil defense under the Government of Republic of Tajikistan provides a stage-by-stage realization of the actions for protection of population and territories from mass-destruction weapon. One of the important actions is provision and accumulation of the means of personal protection, keeping of this means. The means of personal protections are laboratory tested by the specialists of the Committee of emergency situations and civil defense. Analytical data of the Committee of emergency situations and civil defense allows making some conclusions concerning experienced storage of the means of personal protection. A general analysis of laboratory test indicates that: laboratory tests of filtering boxes indicate the preservation of air flow resistance and waterproof due to the adherence to the rules of keeping; laboratory tests of the front parts of the gas masks and their hardness and waterproof, and the waterproof of the valves show that the front part is dependent on meteorological character of the region of storage at long-term keeping. Conclusions

Selection criteria limit generalizability of smoking pharmacotherapy studies differentially across clinical trials and laboratory studies: A systematic review on varenicline.

Science.gov (United States)

Motschman, Courtney A; Gass, Julie C; Wray, Jennifer M; Germeroth, Lisa J; Schlienz, Nicolas J; Munoz, Diana A; Moore, Faith E; Rhodes, Jessica D; Hawk, Larry W; Tiffany, Stephen T

2016-12-01

The selection criteria used in clinical trials for smoking cessation and in laboratory studies that seek to understand mechanisms responsible for treatment outcomes may limit their generalizability to one another and to the general population. We reviewed studies on varenicline versus placebo and compared eligibility criteria and participant characteristics of clinical trials (N=23) and laboratory studies (N=22) across study type and to nationally representative survey data on adult, daily USA smokers (2014 National Health Interview Survey; 2014 National Survey on Drug Use and Health). Relative to laboratory studies, clinical trials more commonly reported excluding smokers who were unmotivated to quit and for specific medical conditions (e.g., cardiovascular disease, COPD), although both study types frequently reported excluding for general medical or psychiatric reasons. Laboratory versus clinical samples smoked less, had lower nicotine dependence, were younger, and more homogeneous with respect to smoking level and nicotine dependence. Application of common eligibility criteria to national survey data resulted in considerable elimination of the daily-smoking population for both clinical trials (≥47%) and laboratory studies (≥39%). Relative to the target population, studies in this review recruited participants who smoked considerably more and had a later smoking onset age, and were under-representative of Caucasians. Results suggest that selection criteria of varenicline studies limit generalizability in meaningful ways, and differences in criteria across study type may undermine efforts at translational research. Recommendations for improvements in participant selection and reporting standards are discussed. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Safety in laboratories: Indian scenario.

Science.gov (United States)

Mustafa, Ajaz; Farooq, A Jan; Qadri, Gj; S A, Tabish

2008-07-01

Health and safety in clinical laboratories is becoming an increasingly important subject as a result of emergence of highly infectious diseases such as Hepatitis and HIV. A cross sectional study was carried out to study the safety measures being adopted in clinical laboratories of India. Heads of laboratories of teaching hospitals of India were subjected to a standardized, pretested questionnaire. Response rate was 44.8%. only 60% of laboratories had person in-charge of safety in laboratory. Seventy three percent of laboratories had safety education program regarding hazards. In 91% of laboratories staff is using protective clothing while working in laboratories. Hazardous material regulations are followed in 78% of laboratories. Regular health check ups are carried among laboratory staff in 43.4% of laboratories.Safety manual is available in 56.5% of laboratories. 73.9% of laboratories are equipped with fire extinguishers. Fume cupboards are provided in 34.7% of laboratories and they are regularly checked in 87.5% of these laboratories. In 78.26% of laboratories suitable measures are taken to minimize formation of aerosols.In 95.6% of laboratories waste is disposed off as per bio-medical waste management handling rules. Laboratory of one private medical college was accredited with NABL and safety parameters were better in that laboratory. Installing safety engineered devices apparently contributes to significant decrease in injuries in laboratories; laboratory safety has to be a part of overall quality assurance programme in hospitals. Accreditation has to be made necessary for all laboratories.

Clinical and laboratory features of patients of Vietnamese descent with systemic lupus erythematosus.

Science.gov (United States)

Phan, J C; Bush, T M; Donald, F; Ward, M

1999-01-01

The prevalence rate and disease manifestations of systemic lupus erythematosus (SLE) have been noted to vary among different ethnic groups. There has been no description in the English literature of SLE in the Vietnamese population. This is the first report, which details the clinical and laboratory features as well as an estimation of the prevalence of SLE in patients with a Vietnamese ancestry living in the United States. We performed a retrospective chart review of clinical and laboratory features of patients of Vietnamese descent with SLE. The case finding was performed by a review of the rheumatology clinic records at two large teaching hospitals in Santa Clara County searching for patients with SLE with a Vietnamese surname. In addition, we recruited patients by contacting all of the rheumatologists practicing in the county. Twenty-three patients of Vietnamese descent were identified with SLE in Santa Clara County. The estimated prevalence of SLE in the patients of Vietnamese descent was 42 cases per 100 000 persons. Eighty-seven per cent of the cases were born in Vietnam. The clinical and laboratory features of SLE were similar to prior published reviews except for a relatively high prevalence of anti-RNP antibody (54%). The patients with anti-RNP antibody exhibited features of overlap syndrome. There was a high rate of exposure to tuberculosis (TB). Fifty-eight per cent of patients had a positive purified protein derivative (PPD) skin test and 27% of patients had a history of clinical TB. Forty-four per cent of patients had evidence of hepatitis B exposure. The prevalence of SLE in the Vietnamese population in Santa Clara County is similar to that of other Asian populations. There was a relatively high prevalence of anti-RNP antibody in our patient group which was associated with overlap features. As expected in an immigrant population from Southeast Asia, there was a high rate of prior exposure to tuberculosis and hepatitis B. Clinicians should diligently

National laboratories

International Nuclear Information System (INIS)

Moscati, G.

1983-01-01

The foundation of a 'National Laboratory' which would support a Research center in synchrotron radiation applications is proposed. The essential features of such a laboratory differing of others centers in Brazil are presented. (L.C.) [pt

Spectrometric devices of itinerant radiometric laboratory

International Nuclear Information System (INIS)

Dolgirev, E.I.; Moroz, G.L.; Shchedrin, D.A.

1978-01-01

Scintillation gamma-spectrometer is described designed for mobile radiometric laboratory for individual monitoring of internal γ-radiation of members of the general population and service personnel as well as for analysis of the isotopic composition of radiocontaminants in the environment. Description and technical features of device are given. The detection unit consists of detectors made on the basis of NaI(Tl) monocrystals 63 x 63 mm in size. The unit permits measurement of various levels of gamma-emitting nuclides throughout the body and in the thyroid and lungs of man. Provision is made for measuring samples with high specific activities (more than 10 -5 Cu/g) and for examining individuals having high levels of incorporated radionuclides

Laboratory colonization stabilizes the naturally dynamic microbiome composition of field collected Dermacentor andersoni ticks.

Science.gov (United States)

Gall, Cory A; Scoles, Glen A; Magori, Krisztian; Mason, Kathleen L; Brayton, Kelly A

2017-10-04

Nearly a quarter of emerging infectious diseases identified in the last century are arthropod-borne. Although ticks and insects can carry pathogenic microorganisms, non-pathogenic microbes make up the majority of their microbial communities. The majority of tick microbiome research has had a focus on discovery and description; very few studies have analyzed the ecological context and functional responses of the bacterial microbiome of ticks. The goal of this analysis was to characterize the stability of the bacterial microbiome of Dermacentor andersoni ticks between generations and two populations within a species. The bacterial microbiome of D. andersoni midguts and salivary glands was analyzed from populations collected at two different ecologically distinct sites by comparing field (F1) and lab-reared populations (F1-F3) over three generations. The microbiome composition of pooled and individual samples was analyzed by sequencing nearly full-length 16S rRNA gene amplicons using a Pacific Biosciences CCS platform that allows identification of bacteria to the species level. In this study, we found that the D. andersoni microbiome was distinct in different geographic populations and was tissue specific, differing between the midgut and the salivary gland, over multiple generations. Additionally, our study showed that the microbiomes of laboratory-reared populations were not necessarily representative of their respective field populations. Furthermore, we demonstrated that the microbiome of a few individual ticks does not represent the microbiome composition at the population level. We demonstrated that the bacterial microbiome of D. andersoni was complex over three generations and specific to tick tissue (midgut vs. salivary glands) as well as geographic location (Burns, Oregon vs. Lake Como, Montana vs. laboratory setting). These results provide evidence that habitat of the tick population is a vital component of the complexity of the bacterial microbiome of ticks

Personalized laboratory medicine

DEFF Research Database (Denmark)

Pazzagli, M.; Malentacchi, F.; Mancini, I.

2015-01-01

diagnostic tools and expertise and commands proper state-of-the-art knowledge about Personalized Medicine and Laboratory Medicine in Europe, the joint Working Group "Personalized Laboratory Medicine" of the EFLM and ESPT societies compiled and conducted the Questionnaire "Is Laboratory Medicine ready...... in "omics"; 2. Additional training for the current personnel focused on the new methodologies; 3. Incorporation in the Laboratory of new competencies in data interpretation and counselling; 4. Improving cooperation and collaboration between professionals of different disciplines to integrate information...

Medical record automation at the Los Alamos Scientific Laboratory

International Nuclear Information System (INIS)

Hogle, G.O.; Grier, R.S.

1979-01-01

With the increase in population at the Los Alamos Scientific Laboratory and the growing concern over employee health, especially concerning the effects of the work environment, the Occupational Medicine Group decided to automate its medical record keeping system to meet these growing demands. With this computer system came not only the ability for long-term study of the work environment verses employee health, but other benefits such as more comprehensive records, increased legibility, reduced physician time, and better records management

Conserved G-matrices of morphological and life-history traits among continental and island blue tit populations.

Science.gov (United States)

Delahaie, B; Charmantier, A; Chantepie, S; Garant, D; Porlier, M; Teplitsky, C

2017-08-01

The genetic variance-covariance matrix (G-matrix) summarizes the genetic architecture of multiple traits. It has a central role in the understanding of phenotypic divergence and the quantification of the evolutionary potential of populations. Laboratory experiments have shown that G-matrices can vary rapidly under divergent selective pressures. However, because of the demanding nature of G-matrix estimation and comparison in wild populations, the extent of its spatial variability remains largely unknown. In this study, we investigate spatial variation in G-matrices for morphological and life-history traits using long-term data sets from one continental and three island populations of blue tit (Cyanistes caeruleus) that have experienced contrasting population history and selective environment. We found no evidence for differences in G-matrices among populations. Interestingly, the phenotypic variance-covariance matrices (P) were divergent across populations, suggesting that using P as a substitute for G may be inadequate. These analyses also provide the first evidence in wild populations for additive genetic variation in the incubation period (that is, the period between last egg laid and hatching) in all four populations. Altogether, our results suggest that G-matrices may be stable across populations inhabiting contrasted environments, therefore challenging the results of previous simulation studies and laboratory experiments.

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

Directory of Open Access Journals (Sweden)

Catalá SS

2004-01-01

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

Fitness decline under osmotic stress in Caenorhabditis elegans populations subjected to spontaneous mutation accumulation at varying population sizes.

Science.gov (United States)

Katju, Vaishali; Packard, Lucille B; Keightley, Peter D

2018-04-01

The consequences of mutations for population fitness depends on their individual selection coefficients and the effective population size. An earlier study of Caenorhabditis elegans spontaneous mutation accumulation lines evolved for 409 generations at three population sizes found that N e   = 1 populations declined significantly in fitness whereas the fitness of larger populations (N e   = 5, 50) was indistinguishable from the ancestral control under benign conditions. To test if larger MA populations harbor a load of cryptic deleterious mutations that are obscured under benign laboratory conditions, we measured fitness under osmotic stress via exposure to hypersaline conditions. The fitness of N e   = 1 lines exhibited a further decline under osmotic stress compared to benign conditions. However, the fitness of larger populations remained indistinguishable from that of the ancestral control. The average effects of deleterious mutations in N e   = 1 lines were estimated to be 22% for productivity and 14% for survivorship, exceeding values previously detected under benign conditions. Our results suggest that fitness decline is due to large effect mutations that are rapidly removed via selection even in small populations, with implications for conservation practices. Genetic stochasticity may not be as potent and immediate a threat to the persistence of small populations as other demographic and environmental stochastic factors. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

A professional development model for medical laboratory scientists working in the microbiology laboratory.

Science.gov (United States)

Amerson, Megan H; Pulido, Lila; Garza, Melinda N; Ali, Faheem A; Greenhill, Brandy; Einspahr, Christopher L; Yarsa, Joseph; Sood, Pramilla K; Hu, Peter C

2012-01-01

The University of Texas M.D. Anderson Cancer Center, Division of Pathology and Laboratory Medicine is committed to providing the best pathology and medicine through: state-of-the art techniques, progressive ground-breaking research, education and training for the clinical diagnosis and research of cancer and related diseases. After surveying the laboratory staff and other hospital professionals, the Department administrators and Human Resource generalists developed a professional development model for Microbiology to support laboratory skills, behavior, certification, and continual education within its staff. This model sets high standards for the laboratory professionals to allow the labs to work at their fullest potential; it provides organization to training technologists based on complete laboratory needs instead of training technologists in individual areas in which more training is required if the laboratory needs them to work in other areas. This model is a working example for all microbiology based laboratories who want to set high standards and want their staff to be acknowledged for demonstrated excellence and professional development in the laboratory. The PDM model is designed to focus on the needs of the laboratory as well as the laboratory professionals.

Synchronization and survival of connected bacterial populations

Science.gov (United States)

Gokhale, Shreyas; Conwill, Arolyn; Ranjan, Tanvi; Gore, Jeff

Migration plays a vital role in controlling population dynamics of species occupying distinct habitat patches. While local populations are vulnerable to extinction due to demographic or environmental stochasticity, migration from neighboring habitat patches can rescue these populations through colonization of uninhabited regions. However, a large migratory flux can synchronize the population dynamics in connected patches, thereby enhancing the risk of global extinction during periods of depression in population size. Here, we investigate this trade-off between local rescue and global extinction experimentally using laboratory populations of E. coli bacteria. Our model system consists of co-cultures of ampicillin resistant and chloramphenicol resistant strains that form a cross-protection mutualism and exhibit period-3 oscillations in the relative population density in the presence of both antibiotics. We quantify the onset of synchronization of oscillations in a pair of co-cultures connected by migration and demonstrate that period-3 oscillations can be disturbed for moderate rates of migration. These features are consistent with simulations of a mechanistic model of antibiotic deactivation in our system. The simulations further predict that the probability of survival of connected populations in high concentrations of antibiotics is maximized at intermediate migration rates. We verify this prediction experimentally and show that survival is enhanced through a combination of disturbance of period-3 oscillations and stochastic re-colonization events.

A Study of Children's Geographic Access to Health Services (Health Care Centers and Clinical Laboratories in Kermanshah City, Iran

Directory of Open Access Journals (Sweden)

Sohyla Reshadat

2018-02-01

Full Text Available Background Given that the protection of children's health is of special importance due to their special age and physical conditions, the present study aimed to investigate the condition of children's Geographic access to health services (Health Centers and Clinical Laboratories in Kermanshah city, Iran. Materials and Methods: In this applied study, the research approach was descriptive-analytic using quantitative models in Geographic information system (GIS environment. The statistical population was the whole population of young girls aged 0-14 years old in Kermanshah, Iran. Moreover, to evaluate the spatial deployment pattern of health services and the correct and true access of this groupto such services, all data and information were collected through the Iranian Statistics Center and evaluated using the Arc-GIS Software. The latest published population statistics on the Population and Housing Census in 2011 were considered the basis for the analyses. Results: The results of the present study demonstrated that more than 40% and 60% of the young girls aged 0-14 years old in Kermanshah were deprived of proper access to health centers and clinical laboratories, respectively. In terms of the status of children’s access in the Second Scenario (access to health services by vehicles and during 5, 10, and 15 minutes, about 5.53%, 93.1% and 15.1% lacked access to health centers, respectively. In addition, in terms of the status of children’s access to clinical laboratories during 5, 10, and 15 minutes, 17.26%, 65.4% and 51% lacked access to clinical laboratories, respectively. Conclusion: The access of young girls aged 0-14 years old to health services in Kermanshah was undesirable in the access to health services through walking. Additionally, the access of this groupto health services in the access to health services by vehicles was far better than the first one.

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

Directory of Open Access Journals (Sweden)

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.

Laboratory equipment maintenance: a critical bottleneck for strengthening health systems in sub-Saharan Africa?

Science.gov (United States)

Fonjungo, Peter N; Kebede, Yenew; Messele, Tsehaynesh; Ayana, Gonfa; Tibesso, Gudeta; Abebe, Almaz; Nkengasong, John N; Kenyon, Thomas

2012-02-01

Properly functioning laboratory equipment is a critical component for strengthening health systems in developing countries. The laboratory can be an entry point to improve population health and care of individuals for targeted diseases - prevention, care, and treatment of TB, HIV/AIDS, and malaria, plus maternal and neonatal health - as well as those lacking specific attention and funding. We review the benefits and persistent challenges associated with sustaining laboratory equipment maintenance. We propose equipment management policies as well as a comprehensive equipment maintenance strategy that would involve equipment manufacturers and strengthen local capacity through pre-service training of biomedical engineers. Strong country leadership and commitment are needed to assure development and sustained implementation of policies and strategies for standardization of equipment, and regulation of its procurement, donation, disposal, and replacement.

A Dual Case Study: Students' Perceptions, Self-Efficacy and Understanding of the Nature of Science in Varied Introductory Biology Laboratories

Science.gov (United States)

Quigley, Dena Beth Boans

Since World War II, science education has been at the forefront of curricular reforms. Although the philosophical approach to science education has changed numerous times, the importance of the laboratory has not waned. A laboratory is meant to allow students to encounter scientific concepts in a very real, hands-on way so that they are able to either recreate experiments that have given rise to scientific theories or to use science to understand a new idea. As the interactive portion of science courses, the laboratory should not only reinforce conceptual ideas, but help students to understand the process of science and interest them in learning more about science. However, most laboratories have fallen into a safe pattern having teachers and students follow a scientific recipe, removing the understanding of and interest in science for many participants. In this study, two non-traditional laboratories are evaluated and compared with a traditional laboratory in an effort to measure student satisfaction, self-efficacy, attitudes towards science, and finally their epistemology of the nature of science (NOS). Students in all populations were administered a survey at the beginning and the end of their spring 2016 laboratory, and the survey was a mixture of qualitative questions and quantitative instruments. Overall, students who participated in one of the non-traditional labs rated their satisfaction higher and used affirming supportive statements. They also had significant increases in self-efficacy from pre to post, while the students in the traditional laboratory had a significant decrease. The students in the traditional laboratory had significant changed in attitudes towards science, as did the students in one of the non-traditional laboratories. All students lacked a firm grasp of the tenets of NOS, although one laboratory that includes explicit discussions of NOS saw improvement in at least on tenet. Data for two non-major biology laboratory populations was

Autovalidation and automation of the postanalytical phase of routine hematology and coagulation analyses in a university hospital laboratory.

Science.gov (United States)

Mlinaric, Ana; Milos, Marija; Coen Herak, Désirée; Fucek, Mirjana; Rimac, Vladimira; Zadro, Renata; Rogic, Dunja

2018-02-23

The need to satisfy high-throughput demands for laboratory tests continues to be a challenge. Therefore, we aimed to automate postanalytical phase in hematology and coagulation laboratory by autovalidation of complete blood count (CBC) and routine coagulation test results (prothrombin time [PT], international normalized ratio [PT-INR], activated partial thromboplastin time [APTT], fibrinogen, antithrombin activity [AT] and thrombin time [TT]). Work efficacy and turnaround time (TAT) before and after implementation of automated solutions will be compared. Ordering panels tailored to specific patient populations were implemented. Rerun and reflex testing rules were set in the respective analyzers' software (Coulter DxH Connectivity 1601, Beckman Coulter, FL, USA; AutoAssistant, Siemens Healthcare Diagnostics, Germany), and sample status information was transferred into the laboratory information system. To evaluate if the automation improved TAT and efficacy, data from manually verified results in September and October of 2015 were compared with the corresponding period in 2016 when autovalidation was implemented. Autovalidation rates of 63% for CBC and 65% for routine coagulation test results were achieved. At the TAT of 120 min, the percentage of reported results increased substantially for all analyzed tests, being above 90% for CBC, PT, PT-INR and fibrinogen and 89% for APTT. This output was achieved with three laboratory technicians less compared with the period when the postanalytical phase was not automated. Automation allowed optimized laboratory workflow for specific patient populations, thereby ensuring standardized results reporting. Autovalidation of test results proved to be an efficient tool for improvement of laboratory work efficacy and TAT.

Experimental transmission of Leishmania infantum by two major vectors: a comparison between a viscerotropic and a dermotropic strain.

Science.gov (United States)

Maia, Carla; Seblova, Veronika; Sadlova, Jovana; Votypka, Jan; Volf, Petr

2011-06-01

We quantified Leishmania infantum parasites transmitted by natural vectors for the first time. Both L. infantum strains studied, dermotropic CUK3 and viscerotropic IMT373, developed well in Phlebotomus perniciosus and Lutzomyia longipalpis. They produced heavy late-stage infection and colonized the stomodeal valve, which is a prerequisite for successful transmission. Infected sand fly females, and especially those that transmit parasites, feed significantly longer on the host (1.5-1.8 times) than non-transmitting females. Quantitative PCR revealed that P. perniciosus harboured more CUK3 strain parasites, while in L. longipalpis the intensity of infection was higher for the IMT373 strain. However, in both sand fly species the parasite load transmitted was higher for the strain with dermal tropism (CUK3). All but one sand fly female infected by the IMT373 strain transmitted less than 600 promastigotes; in contrast, 29% of L. longipalpis and 14% of P. perniciosus infected with the CUK3 strain transmitted more than 1000 parasites. The parasite number transmitted by individual sand flies ranged from 4 up to 4.19×10(4) promastigotes; thus, the maximal natural dose found was still about 250 times lower than the experimental challenge dose used in previous studies. This finding emphasizes the importance of determining the natural infective dose for the development of an accurate experimental model useful for the evaluation of new drugs and vaccines.

SPATIAL DISTRIBUTION OF PHLEBOTOMINAE IN PUERTO IGUAZU-MISIONES, ARGENTINA-BRAZIL-PARAGUAY BORDER AREA

Directory of Open Access Journals (Sweden)

Maria Soledad Santini

2013-07-01

Full Text Available SUMMARY The first Argentinian autochthonous human case of visceral leishmaniasis (VL was confirmed in Posadas (Misiones in 2006. Since then, the disease has increased its incidence and geographical distribution. In the 2006-2012 period, 107 human cases were detected (11 deaths. The presence of Lutzomyia longipalpis was detected in peridomiciles in Puerto Iguazú urban area in 2010; some of these findings were associated with households where cases of canine VL had already been reported. The objective of this study was to ascertain the abundance and spatial distribution of Lu. longipalpis in Puerto Iguazú City, on the Argentina-Brazil-Paraguay border. Lu. longipalpis proved to be exclusively urban and was found in 31% of the households sampled (n = 53, 67% of which belonged to areas of low abundance, 20% to areas of moderate abundance and 13% to areas of high abundance. Nyssomyia whitmani was the only species found both in urban and peri-urban environments, and Migonemyia migonei was registered only on the outskirts of the city. Due to the fact that Puerto Iguazú is considered to be at moderate risk at the moment, it is necessary to intensify human and canine case controls, as well as take integrated prevention and control measures regarding the environment, vectors and reservoirs on the Argentina-Brazil-Paraguay border area.

Lundep, a sand fly salivary endonuclease increases Leishmania parasite survival in neutrophils and inhibits XIIa contact activation in human plasma.

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Andrezza C Chagas

2014-02-01

Full Text Available Neutrophils are the host's first line of defense against infections, and their extracellular traps (NET were recently shown to kill Leishmania parasites. Here we report a NET-destroying molecule (Lundep from the salivary glands of Lutzomyia longipalpis. Previous analysis of the sialotranscriptome of Lu. longipalpis showed the potential presence of an endonuclease. Indeed, not only was the cloned cDNA (Lundep shown to encode a highly active ss- and dsDNAse, but also the same activity was demonstrated to be secreted by salivary glands of female Lu. longipalpis. Lundep hydrolyzes both ss- and dsDNA with little sequence specificity with a calculated DNase activity of 300000 Kunitz units per mg of protein. Disruption of PMA (phorbol 12 myristate 13 acetate- or parasite-induced NETs by treatment with recombinant Lundep or salivary gland homogenates increases parasite survival in neutrophils. Furthermore, co-injection of recombinant Lundep with metacyclic promastigotes significantly exacerbates Leishmania infection in mice when compared with PBS alone or inactive (mutagenized Lundep. We hypothesize that Lundep helps the parasite to establish an infection by allowing it to escape from the leishmanicidal activity of NETs early after inoculation. Lundep may also assist blood meal intake by lowering the local viscosity caused by the release of host DNA and as an anticoagulant by inhibiting the intrinsic pathway of coagulation.

Development policy for the Brazilian health industry and qualification of national public laboratories

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Ana Luiza d'Ávila Viana

Full Text Available Abstract: Technological innovations play a decisive role in societies' development by contributing to economic growth and the population's welfare. The state has a key role in this process by inducing innovative behavior, strategies, and decisions. This study addresses Brazil's current policy for development of the health industry and its effects on qualification of national public laboratories by contextualizing different cycles of interaction between health policy and the industrial base, discussing the government's development strategy and the transfer and absorption of health technology (through Industrial Development Partnerships, and presenting two current partnerships involving public laboratories in the production of medicines and vaccines.

Teaching Population Growth Using Cultures of Vinegar Eels, "Turbatrix aceti" (Nematoda)

Science.gov (United States)

Wallace, Robert L.

2005-01-01

A simple laboratory exercise is presented that follows the population growth of the common vinegar eel, "Turbatrix aceti" (Nematoda), in a microcosm using a simple culture medium. It lends itself to an exercise in a single semester course. (Contains 4 figures.)

Customer satisfaction survey with clinical laboratory and phlebotomy services at a tertiary care unit level.

Science.gov (United States)

Koh, Young Rae; Kim, Shine Young; Kim, In Suk; Chang, Chulhun L; Lee, Eun Yup; Son, Han Chul; Kim, Hyung Hoi

2014-09-01

We performed customer satisfaction surveys for physicians and nurses regarding clinical laboratory services, and for outpatients who used phlebotomy services at a tertiary care unit level to evaluate our clinical laboratory and phlebotomy services. Thus, we wish to share our experiences with the customer satisfaction survey for clinical laboratory and phlebotomy services. Board members of our laboratory designed a study procedure and study population, and developed two types of questionnaire. A satisfaction survey for clinical laboratory services was conducted with 370 physicians and 125 nurses by using an online or paper questionnaire. The satisfaction survey for phlebotomy services was performed with 347 outpatients who received phlebotomy services by using computer-aided interviews. Mean satisfaction scores of physicians and nurses was 58.1, while outpatients' satisfaction score was 70.5. We identified several dissatisfactions with our clinical laboratory and phlebotomy services. First, physicians and nurses were most dissatisfied with the specimen collection and delivery process. Second, physicians and nurses were dissatisfied with phlebotomy services. Third, molecular genetic and cytogenetic tests were found more expensive than other tests. This study is significant in that it describes the first reference survey that offers a survey procedure and questionnaire to assess customer satisfaction with clinical laboratory and phlebotomy services at a tertiary care unit level.

Sandia National Laboratories

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Gilliom, Laura R.

1992-01-01

Sandia National Laboratories has identified technology transfer to U.S. industry as a laboratory mission which complements our national security mission and as a key component of the Laboratory's future. A number of technology transfer mechanisms - such as CRADA's, licenses, work-for-others, and consortia - are identified and specific examples are given. Sandia's experience with the Specialty Metals Processing Consortium is highlighted with a focus on the elements which have made it successful. A brief discussion of Sandia's potential interactions with NASA under the Space Exploration Initiative was included as an example of laboratory-to-NASA technology transfer. Viewgraphs are provided.

Primary Hydatid Cyst of the Kidney and Ureter with Hydatiduria in a Laboratory Worker: A Case Report

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Venkatesh Seetharam

2012-01-01

Full Text Available Hydatid disease is frequent in endemic regions and sheep farming areas. Most common localization of hydatid cyst occurs in liver followed by lungs. Renal hydatid cyst constitutes about 2–4% of all locations. We report a case of left renal hydatid from a laboratory technician admitted in a tertiary care hospital. There were few cases of renal hydatid disease reported in India among general population but to the best of our knowledge never reported from laboratory worker. The possibility of laboratory-acquired infection cannot be ruled out in this case due to lack of precautionary measures and containment facilities in resource-constrained setting.

Improved population balance model for straining-dominant deep bed filtration using network calculations

DEFF Research Database (Denmark)

Yuan, Hao; You, Zhenjiang; Shapiro, Alexander

2013-01-01

Colloidal-suspension flow in porous media is modelled simultaneously by the large scale population balance equations and by the microscale network model. The phenomenological parameter of the correlation length in the population balance model is determined from the network modelling. It is found...... out that the correlation length in the population balance model depends on the particle size. This dependency calculated by two-dimensional network has the same tendency as that obtained from the laboratory tests in engineered porous media....

Laboratory longevity and competitiveness of Dacus ciliatus Loew (Diptera: Tephritidae) following sub-sterilizing gamma irradiation.

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Nemny-Lavy, E; Nestel, D; Rempoulakis, P

2016-06-01

The effect of a sub-sterilizing gamma radiation dose on Dacus ciliatus adults was investigated to assess the suitability of the sterile insect technique (SIT) as an alternative method to control this pest. Late pupae (48 h prior to adult emergence) from a laboratory strain were irradiated with 120 Gy of gamma rays emitted by a 60Co source. Following adult emergence, the mortality of irradiated and non-irradiated cohorts was recorded. Over a period of 50 days after emergence, no significant negative effects of irradiation upon the longevity of male or female laboratory flies were observed. A laboratory competitiveness study (Fried test), using irradiated laboratory and wild males at a ratio of 3:1 was conducted to assess the ability of irradiated males to reduce the egg hatch rates of a wild population. The overall competitiveness was found to be ca. 0.32, suggesting a reduced, but satisfactory, quality of irradiated laboratory as compared with wild males. Based on the above findings, we calculated and proposed effective male release ratios for field application of SIT against D. ciliatus.

NATURAL RESOURCE MANAGEMENT PLAN FOR BROOKHAVEN NATIONAL LABORATORY.

Energy Technology Data Exchange (ETDEWEB)

GREEN,T.ET AL.

2003-12-31

Brookhaven National Laboratory (BNL) is located near the geographic center of Long Island, New York. The Laboratory is situated on 5,265 acres of land composed of Pine Barrens habitat with a central area developed for Laboratory work. In the mid-1990s BNL began developing a wildlife management program. This program was guided by the Wildlife Management Plan (WMP), which was reviewed and approved by various state and federal agencies in September 1999. The WMP primarily addressed concerns with the protection of New York State threatened, endangered, or species of concern, as well as deer populations, invasive species management, and the revegetation of the area surrounding the Relativistic Heavy Ion Collider (RHIC). The WMP provided a strong and sound basis for wildlife management and established a basis for forward motion and the development of this document, the Natural Resource Management Plan (NRMP), which will guide the natural resource management program for BNL. The body of this plan establishes the management goals and actions necessary for managing the natural resources at BNL. The appendices provide specific management requirements for threatened and endangered amphibians and fish (Appendices A and B respectively), lists of actions in tabular format (Appendix C), and regulatory drivers for the Natural Resource Program (Appendix D). The purpose of the Natural Resource Management Plan is to provide management guidance, promote stewardship of the natural resources found at BNL, and to integrate their protection with pursuit of the Laboratory's mission. The philosophy or guiding principles of the NRMP are stewardship, adaptive ecosystem management, compliance, integration with other plans and requirements, and incorporation of community involvement, where applicable.

Distribution of phlebotomine sandflies (Diptera: Psychodidae of medical importance in Mato Grosso State, Brazil Distribuição de flebotomíneos (Diptera: Psychodidae de importância médica no Estado de Mato Grosso, Brasil

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Ana Lúcia Maria Ribeiro

2007-10-01

Full Text Available Intense environmental impacts, causing alterations of the natural habitats of fauna, including those of sandfly disease vectors are observed in Mato Grosso State, Central Brazil. Entomologic survey of phlebotomines was based on light trap and was carried out by entomological nucleus of the FUNASA and SES in the period between 1996 and 2001. Eighty eight species were identified, including the following sandflies with medical importance to leishmaniasis: Lutzomyia amazonensis, L. anduzei, L. antunesi, L. ayrozai, L. carrerai carrerai, L. complexa, L. cruzi, L. flaviscutellata, L. intermedia, L. longipalpis, L. migonei, L. paraensis, L. ubiquitalis, L. whitmani and L. yuilli yuilli. Most sandflies of medical importance occurred in the Amazon forest and savannah. L. longipalpis and L. cruzi had high densities in the savannah region. L. flaviscutellata is predominating in both the Amazon forest and the savannah region. L. whitmani and L. antunesi were sampled in the Amazon forest, savannah and marsh land.O estado de Mato Grosso, Brasil vem sendo grandemente impactado, o que provoca uma alteração no habitat natural da fauna, incluindo-se os vetores das leishmanioses. Foram analisados dados de levantamentos entomológicos realizados pela FUNASA e SES no período de 1996 a 2001. Foram capturados indivíduos pertencentes a 88 espécies, sendo as de importância para a transmissão das leishmanioses: Lutzomyia amazonensis, L. anduzei, L. ayrozai, L. carrerai carrerai, L. complexa, L. cruzi, L. flaviscutellata, L. intermedia, L. longipalpis, L. migonei, L. paraensis, L. ubiquitalis, L. whitmani e L. yuilli yuilli, as quais foram plotadas no mapa do Estado. A maioria das espécies de importância médica compartilha a vegetação de floresta Amazônica e cerrado. L. longipalpis e L. cruzi possuem altas densidades na região de cerrado. L. flaviscutellata predomina na floresta Amazônica e no cerrado. L. whitmani e L. antunesi foram capturadas na floresta

Physical Sciences Laboratory (PSL)

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Federal Laboratory Consortium — PNNL's Physical Sciences Laboratory (PSL) houses 22 research laboratories for conducting a wide-range of research including catalyst formulation, chemical analysis,...

Distributed Energy Technology Laboratory

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Federal Laboratory Consortium — The Distributed Energy Technologies Laboratory (DETL) is an extension of the power electronics testing capabilities of the Photovoltaic System Evaluation Laboratory...

Optics/Optical Diagnostics Laboratory

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Federal Laboratory Consortium — The Optics/Optical Diagnostics Laboratory supports graduate instruction in optics, optical and laser diagnostics and electro-optics. The optics laboratory provides...

Data Driven Approach for High Resolution Population Distribution and Dynamics Models

Energy Technology Data Exchange (ETDEWEB)

Bhaduri, Budhendra L [ORNL; Bright, Eddie A [ORNL; Rose, Amy N [ORNL; Liu, Cheng [ORNL; Urban, Marie L [ORNL; Stewart, Robert N [ORNL

2014-01-01

High resolution population distribution data are vital for successfully addressing critical issues ranging from energy and socio-environmental research to public health to human security. Commonly available population data from Census is constrained both in space and time and does not capture population dynamics as functions of space and time. This imposes a significant limitation on the fidelity of event-based simulation models with sensitive space-time resolution. This paper describes ongoing development of high-resolution population distribution and dynamics models, at Oak Ridge National Laboratory, through spatial data integration and modeling with behavioral or activity-based mobility datasets for representing temporal dynamics of population. The model is resolved at 1 km resolution globally and describes the U.S. population for nighttime and daytime at 90m. Integration of such population data provides the opportunity to develop simulations and applications in critical infrastructure management from local to global scales.

Public census data on CD-ROM at Lawrence Berkeley Laboratory. Revision 1

Energy Technology Data Exchange (ETDEWEB)

Merrill, D.W.

1992-07-02

In connection with the Comprehensive Epidemiologic Data Resource (CEDR) and Populations at Risk to Environmental Pollution (PAREP) projects, of the Information and Computing Sciences Division (ICSD) at Lawrence Berkeley Laboratory (LBL), are using public socioeconomic and geographic data files which are available to CEDR and PAREP collaborators via LBL`s computing network. At this time 67 CD-ROM diskettes (approximately 35 gigabytes) are on line via the Unix file server cedrcd.lbl.gov. Most of the files are from the US Bureau of the Census, and most pertain to the 1990 Census of Population and Housing. This paper contains a list of the CD-ROMs available.

Denver District Laboratory (DEN)

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Federal Laboratory Consortium — Program CapabilitiesDEN-DO Laboratory is a multi-functional laboratory capable of analyzing most chemical analytes and pathogenic/non-pathogenic microorganisms found...

COMMERCIALLY ORIENTED CLINICAL LABORATORIES

Science.gov (United States)

Chapman, W. Max

1964-01-01

Out-of-state flat-rate mail order contract laboratories operating from states which have little or no legal control over them can do business in California without obedience to regulations that govern laboratories located within the state. The flat-rate contract principle under which some out-of-state laboratories operate is illegal in California. The use of such laboratories increases physician liability. Legislation for the control of these laboratories is difficult to construct, and laws which might result would be awkward to administer. The best remedy is for California physicians not to use an out-of-state laboratory offering contracts or conditions that it could not legally offer if it were located in California. PMID:14165875

[Accreditation of medical laboratories].

Science.gov (United States)

Horváth, Andrea Rita; Ring, Rózsa; Fehér, Miklós; Mikó, Tivadar

2003-07-27

In Hungary, the National Accreditation Body was established by government in 1995 as an independent, non-profit organization, and has exclusive rights to accredit, amongst others, medical laboratories. The National Accreditation Body has two Specialist Advisory Committees in the health care sector. One is the Health Care Specialist Advisory Committee that accredits certifying bodies, which deal with certification of hospitals. The other Specialist Advisory Committee for Medical Laboratories is directly involved in accrediting medical laboratory services of health care institutions. The Specialist Advisory Committee for Medical Laboratories is a multidisciplinary peer review group of experts from all disciplines of in vitro diagnostics, i.e. laboratory medicine, microbiology, histopathology and blood banking. At present, the only published International Standard applicable to laboratories is ISO/IEC 17025:1999. Work has been in progress on the official approval of the new ISO 15189 standard, specific to medical laboratories. Until the official approval of the International Standard ISO 15189, as accreditation standard, the Hungarian National Accreditation Body has decided to progress with accreditation by formulating explanatory notes to the ISO/IEC 17025:1999 document, using ISO/FDIS 15189:2000, the European EC4 criteria and CPA (UK) Ltd accreditation standards as guidelines. This harmonized guideline provides 'explanations' that facilitate the application of ISO/IEC 17025:1999 to medical laboratories, and can be used as a checklist for the verification of compliance during the onsite assessment of the laboratory. The harmonized guideline adapted the process model of ISO 9001:2000 to rearrange the main clauses of ISO/IEC 17025:1999. This rearrangement does not only make the guideline compliant with ISO 9001:2000 but also improves understanding for those working in medical laboratories, and facilitates the training and education of laboratory staff. With the

Use and Acceptance of Information and Communication Technology Among Laboratory Science Students

Science.gov (United States)

Barnes, Brenda C.

Online and blended learning platforms are being promoted within laboratory science education under the assumption that students have the necessary skills to navigate online and blended learning environments. Yet little research has examined the use of information and communication technology (ICT) among the laboratory science student population. The purpose of this correlational, survey research study was to explore factors that affect use and acceptance of ICT among laboratory science students through the theoretical lens of the unified theory of acceptance and use of technology (UTAUT) model. An electronically delivered survey drew upon current students and recent graduates (within 2 years) of accredited laboratory science training programs. During the 4 week data collection period, 168 responses were received. Results showed that the UTAUT model did not perform well within this study, explaining 25.2% of the variance in use behavior. A new model incorporating attitudes toward technology and computer anxiety as two of the top variables, a model significantly different from the original UTAUT model, was developed that explained 37.0% of the variance in use behavior. The significance of this study may affect curriculum design of laboratory science training programs wanting to incorporate more teaching techniques that use ICT-based educational delivery, and provide more options for potential students who may not currently have access to this type of training.

The impact of laboratory quality assurance standards on laboratory operational performance

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E Ratseou

2014-01-01

Full Text Available It has become a trend for companies to implement and be certified to various quality management systems so as to improve consistency, reliability, and quality of product delivery to customers. The most common quality management systems adopted are the ISO 9000 series of standards for manufacturing and services related organisations, with ISO 17025 and Good Laboratory Practices (GLP standards adopted specifically by laboratories as quality assurance initiatives. There are various reports on the impact of the ISO 9000 series on organisational performance but no studies or reports have been done on the performance of laboratory standards. Therefore this article reports on a study conducted to investigate the impact of ISO 17025 and GLP on the operational performance of both commercial and non-commercial laboratories. A qualitative research study was conducted to examine the impact standards on the aspects of health and safety, supplier selection and performance, human resources, customer satisfaction and profitability of the laboratory. The data collected suggest that there is no difference in laboratory operational performance with or without the standards. In other words it appears that the basic fundamental requirements inherent with laboratories are sufficient to perform both operationally and optimally. This leads to the view that standards are implemented as a customer requirement and not as an operational requirement.

Laboratory quality assurance and its role in the safeguards analytical laboratory evaluation (SALE) program

International Nuclear Information System (INIS)

Delvin, W.L.; Pietri, C.E.

1981-07-01

Since the late 1960's, strong emphasis has been given to quality assurance in the nuclear industry, particularly to that part involved in nuclear reactors. This emphasis has had impact on the analytical chemistry laboratory because of the importance of analytical measurements in the certification and acceptance of materials used in the fabrication and construction of reactor components. Laboratory quality assurance, in which the principles of quality assurance are applied to laboratory operations, has a significant role to play in processing, fabrication, and construction programs of the nuclear industry. That role impacts not only process control and material certification, but also safeguards and nuclear materials accountability. The implementation of laboratory quality assurance is done through a program plan that specifies how the principles of quality assurance are to be applied. Laboratory quality assurance identifies weaknesses and deficiencies in laboratory operations and provides confidence in the reliability of laboratory results. Such confidence in laboratory measurements is essential to the proper evaluation of laboratories participating in the Safeguards Analytical Laboratory Evaluation (SALE) Program

Safety in the Chemical Laboratory: Safety in the Chemistry Laboratories: A Specific Program.

Science.gov (United States)

Corkern, Walter H.; Munchausen, Linda L.

1983-01-01

Describes a safety program adopted by Southeastern Louisiana University. Students are given detailed instructions on laboratory safety during the first laboratory period and a test which must be completely correct before they are allowed to return to the laboratory. Test questions, list of safety rules, and a laboratory accident report form are…

Vehicle Development Laboratory

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Federal Laboratory Consortium — FUNCTION: Supports the development of prototype deployment platform vehicles for offboard countermeasure systems.DESCRIPTION: The Vehicle Development Laboratory is...

NASA Space Radiation Laboratory

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Federal Laboratory Consortium — The NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory is a NASA funded facility, delivering heavy ion beams to a target area where scientists...

Establishment of a System for Monitoring and Control of Cross Contamination in the Laboratory of Microbiological Analysis of Food during 2009

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Corpa- Iguarán Eduardo Javid

2012-03-01

Full Text Available Within the activities for quality control in the laboratory, the final results of a particular analyteare now recognized as intermediates, due to the relevance given to quality assurance, as the ultimategoal of programs for quality management. This concept makes it necessary to establishmentof integral tools, to detect events such as cross-contamination, and measures to avoid affectingthe analysis method. Objective: to established a system for monitoring and control of crosscontaminationin the laboratory of microbiological analysis of food. Materials and methods:Flowcharts were developed to control the proceedings on the populations of aerobe mesophilicsand molds originated from pollution in the environment, surfaces, sterile material and culturemedia, which included a decision tree designed to perform control actions based on tolerance intervals,which were established as objective tool to decision-making leading to normalize countsof microbial populations in question. Results: Warning limits stricter were obtained for aerobicmesophilic and mold populations in the different controls, except for environment of media preparationand the corresponding for sterile material. Conclusion: The process developed allowedto complement the system of internal quality control in the laboratory, to provide of an objectivetool for closing nonconformities because of cross-contamination.