Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
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| influence of lysates of the salivary glands of lutzomyia longipalpis on the development of a leishmania-major-like parasite in the skin of the golden hamster. | twelve years ago, some mice inoculated with leishmania major were found to develop larger lesions, containing more amastigotes, if the inoculum used to infect them contained a lysate of salivary glands from lutzomyia longipalpis than if no lysate was included. in the present study, outbred golden hamsters (mesocricetus auratus) were each inoculated in a footpad with 10(4), 10(5), 10(6) or 10(7) stationary-phase promastigotes of a leishmania-major-like parasite (mhom/br/71/bh49). some of the inoc ... | 2001 | 11235554 |
| [hourly frequency and seasonality of lutzomyia longipalpis (diptera: psychodidae: phlebotominae) on são luís island, maranhão, brazil]. | this article presents the hourly and seasonal distribution of the lutzomyia longipalpis sand fly captured on são luís island, maranhão state. a total of 11,200 specimens were captured during monthly use of cdc light traps indoors and in animal sheds, between 6:00 pm and 6:00 am, in 1996 and 1997. the sand fly behaved as an annual species, with a high frequency year-round, while it was most abundant during the rainy season (57.2%) as compared to the dry season (42.8%). the highest frequencies dur ... | 2001 | 11241945 |
| [digestive tract microbiota in female lutzomyia longipalpis (lutz & neiva, 1912) (diptera: psychodidae) from colonies feeding on blood meal and sucrose plus blood meal]. | there are very few reports on the microbiota of the digestive tract of sand flies, an important omission considering that blood is not the only meal ingested. male and female sand flies obtain sugar meals from several sources, thereby increasing their chance of infection with microorganisms. chances of contamination are higher when insects are bred in the laboratory, and this may affect the development of leishmania spp. from the digestive tract of 300 sand fly females separated in two groups we ... | 2001 | 11241946 |
| gene flow between natural and domestic populations of lutzomyia longipalpis (diptera: psychodidae) in a restricted focus of american visceral leishmaniasis in venezuela. | the epidemiology of the visceral leishmaniasis in the americas is associated with both a natural and a domestic cycle. the existence of reproductively isolated populations of lutzomyia longipalpis (lutz & neiva), and the scarcity of records of this species from natural habitats in areas where it has been associated with domestic habitats indicated that natural populations could be genetically distinct from domestic ones. therefore, we compared the genetic structure and estimated the gene flow be ... | 2001 | 11268683 |
| characterization of constitutive and putative differentially expressed mrnas by means of expressed sequence tags, differential display reverse transcriptase-pcr and randomly amplified polymorphic dna-pcr from the sand fly vector lutzomyia longipalpis. | molecular studies of insect disease vectors are of paramount importance for understanding parasite-vector relationship. advances in this area have led to important findings regarding changes in vectors' physiology upon blood feeding and parasite infection. mechanisms for interfering with the vectorial capacity of insects responsible for the transmission of diseases such as malaria, chagas disease and dengue fever are being devised with the ultimate goal of developing transgenic insects. a primar ... | 2001 | 11285481 |
| a possible role of bats as a blood source for the leishmania vector lutzomyia longipalpis (diptera: psychodidae). | some evidence suggests that bats may provide an alternative blood source for lutzomyia longipalpis, the main vector of american visceral leishmaniasis. feeding trials were conducted to determine whether l. longipalpis feeds on captive bats. the high feeding success indicated that l. longipalpis is capable of feeding on at least four species of bats. implications for the epidemiology of leishmaniases are discussed. | 2000 | 11304062 |
| human immune response to sand fly salivary gland antigens: a useful epidemiological marker? | antibody (igg) responses to salivary gland homogenate and to a recombinant salivary protein from the sand fly lutzomyia longipalpis were investigated using sera from children living in an endemic area of visceral leishmaniasis in brazil. we classified children into four groups according to their responses to leishmania antigen: (group i) positive serology and positive delayed type hypersensitivity (dth), (group ii) positive serology and negative dth, (group iii) negative serology and positive dt ... | 2000 | 11304066 |
| involvement of pacap receptor in primary afferent fibre-evoked responses of ventral roots in the neonatal rat spinal cord. | the role of pacap receptor in nociceptive transmission was investigated in vitro using maxadilan, a pacap receptor selective agonist and max.d.4, a pacap receptor selective antagonist. potentials, from a ventral root (l3 - l5) of an isolated spinal cord preparation or a spinal cord - saphenous nerve - skin preparation from 0 - 3-day-old rats, were recorded extracellularly. in the isolated spinal cord preparation, single shock stimulation of a dorsal root at c-fibre strength induced a slow depola ... | 2001 | 11309249 |
| the invertebrate growth factor/cecr1 subfamily of adenosine deaminase proteins. | adenosine deaminase (ada) catalyzes the hydrolysis of adenosine to inosine. its lack determines severe combined immunodeficiency in mammals, possibly due to accumulation of extracellular adenosine, which induces apoptosis in lymphocytes (franco et al., 1998). thus, presence of normal levels of ada leads to normal growth and proliferation of lymphocytes. several vertebrate and microbial ada amino-acid sequences are known, with substantial similarity to each other. on the other hand, there are inv ... | 2001 | 11311551 |
| the phlebotominae sand fly (diptera: psychodidae) fauna of two atlantic rain forest reserves in the state of rio de janeiro, brazil. | during two consecutive years, studies on the sand fly fauna in poço das antas and fazenda bom retiro, two atlantic rain forest reserves from the state of rio de janeiro, were performed using shannon traps, cdc light traps and human bait collections. eleven species were identified; lutzomyia longipalpis, l. migonei, l. edwardsi, l. intermedia, l. whitmani, l. fischeri, l. shannoni, l. ayrozai, l. hirsuta, l. monticola and l. misionensis (first occurrence in the state of rio de janeiro). l. interm ... | 2001 | 11313637 |
| effect of lutzomyia whitmani (diptera: psychodidae) salivary gland lysates on leishmania (viannia) braziliensis infection in balb/c mice. | previous reports showed that lutzomyia longipalpis saliva exacerbate leishmania braziliensis infection in mice. the sand fly lu. whitmani is one of the vectors of l. (viannia) braziliensis (lvb), a causative agent of cutaneous leishmaniasis in the state of ceará, brazil. to determine whether saliva of lu. whitmani could increase the infectivity of lvb in mice, we inoculated groups of balb/c mice with lvb promastigotes in the presence or absence of the salivary glands lysate from lu. whitmani. we ... | 2001 | 11313642 |
| courtship song genes and speciation in sand flies. | lutzomyia longipalpis (lutz & neiva, 1912) (diptera: psychodidae: phlebotominae) is a vector of visceral leishmaniasis in the americas and it might represent a complex of sibling species. reproductive isolation between closely related species often involves differences in courtship behaviour. cacophony (cac) and period (per) are two drosophila genes that control features of the "lovesong" males produce during courtship that has been implicated in the sexual isolation between closely related spec ... | 2001 | 11313653 |
| new molecular markers for phlebotomine sand flies. | using degenerate-primers pcr we isolated and sequenced fragments from the sand fly lutzomyia longipalpis homologous to two behavioural genes in drosophila, cacophony and period. in addition we identified a number of other gene fragments that show homology to genes previously cloned in drosophila. a codon usage table for l. longipalpis based on these and other genes was calculated. these new molecular markers will be useful in population genetics and evolutionary studies in phlebotomine sand flie ... | 2001 | 11334955 |
| [lutzomyia longipalpis and leishmaniasis visceral in argentina]. | lutzomyia longipalpis is reported for the second time after 50 years in misiones province, argentina. this insect is the vector of leishmania (l.) chagasi, visceral leishmaniasis' parasite. the literature concerning the 16 visceral leishmaniasis cases in the country is reviewed. the cases were reported from salta, jujuy, santiago del estero and chaco provinces. based on the clinical and entomo-epidemiological data two alternative hypotheses were evaluated: a) visceral leishmaniasis in argentina ... | 2001 | 11374140 |
| canine visceral leishmaniasis in colombia: relationship between clinical and parasitologic status and infectivity for sand flies. | we studied the reservoir competency of canines with distinct clinical presentations of leishmania chagasi infection. the parasitologic status of asymptomatic and symptomatic dogs was determined by standard culture methods infectivity was assessed by multiple xenodiagnoses with lutzomyia longipalpis, over a period of 2-11 months. asymptomatic dogs were non-infective (0 of 5) while 2 of 7 oligosymptomatic dogs infected l longipalpis, transmitting the parasites at low rates (range 0.9-5.2% of engor ... | 2001 | 11442205 |
| heterogeneity of wild leishmania major isolates in experimental murine pathogenicity and specific immune response. | virulence variability was investigated by analyzing the experimental pathogenicity of 19 leishmania major strains in susceptible balb/c mice. twelve strains were isolated from tunisian patients with zoonotic cutaneous leishmaniasis; seven strains were isolated in syria (n = 1), saudi arabia (n = 2), jordan (n = 2), or israel (n = 2). balb/c mice were injected in the hind footpad with 2 x 10(6) amastigotes of the various isolates, and lesion progression was recorded weekly for 9 weeks. interleuki ... | 2001 | 11447167 |
| toward a defined anti-leishmania vaccine targeting vector antigens: characterization of a protective salivary protein. | leishmania parasites are transmitted to their vertebrate hosts by infected phlebotomine sand fly bites. sand fly saliva is known to enhance leishmania infection, while immunity to the saliva protects against infection as determined by coinoculation of parasites with vector salivary gland homogenates (sghs) or by infected sand fly bites (kamhawi, s., y. belkaid, g. modi, e. rowton, and d. sacks. 2000. science. 290:1351-1354). we have now characterized nine salivary proteins of phlebotomus papatas ... | 2001 | 11489952 |
| leishmaniasis vaccination: targeting the source of infection. | 2001 | 11489957 | |
| deltamethrin-impregnated dog collars have a potent anti-feeding and insecticidal effect on lutzomyia longipalpis and lutzomyia migonei. | deltamethrin-impregnated pvc dog collars were tested to assess if they were effective in protecting dogs from sand fly bites of lutzomyia longipalpis and lu. migonei. a protective effect against old world species phlebotomus perniciosus was demonstrated before. four dogs wearing deltamethrin collars and three dogs wearing untreated collars (not impregnated with deltamethrin) were kept in separate kennels for over eight months in a village on the outskirts of fortaleza in ceará, brazil. periodica ... | 2001 | 11562713 |
| [phlebotomine sand flies in the state of tocantins, brazil (diptera: psychodidae)]. | between 1997-1998, the authors carried out sporadic collection of sand flies in the municipalities of paraíso de tocantins, monte do carmo, porto nacional and monte santo all in the tocantins state of northern brazil. human bait was used in monte santo and a battery operated light trap in other municipalities. the ecotypes chosen for the traps were in the peridomiciles, inside the houses, in the forest and the orchard. we identified 2,677 sand flies, belonging to 32 species. the most abundant sp ... | 2001 | 11562724 |
| ultrastructure of endocrine cells from the abdominal midgut epithelium of lutzomyia longipalpis (diptera: psychodidae). | transmission electron microscopy (tem) was used to study two types of endocrine cells front the midgut of adult female luttzomyia longipalpis (lutz & neiva). endocrine cells rarely have been observed in nematocera, even using tem, and were present in small numbers dispersed among the monolayer of midgut digestive epithelial cells. triangular shaped "closed" cells were observed along the basement membrane, bounded on each side by digestive cells; these cells closed distally before reaching the ep ... | 2001 | 11580051 |
| dissociation between vasodilation and leishmania infection-enhancing effects of sand fly saliva and maxadilan. | in this study, the ability of maxadilan and lutzomyia longipalpis salivary gland lysate to enhance the infection of cba mice by leishmania major and of balb/c mice by l. braziliensis was tested. no difference was observed between sizes of lesion in cba mice infected with l. major and treated or not with salivary gland lysate or maxadilan, although they were injected in concentrations that induced cutaneous vasodilation. although parasites were more frequently observed in foot pads and spleens of ... | 2001 | 11685268 |
| development of lutzomyia intermedia and lutzomyia longipalpis (diptera: psychodidae: phlebotominae) larvae in different diets. | 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 bot ... | 2002 | 11706567 |
| hepatitis c virus core and envelope proteins do not suppress the host's ability to clear a hepatic viral infection. | several hepatitis c virus (hcv) proteins have been shown in vitro to interact with host cellular components that are involved in immune regulation. however, there is a paucity of data supporting the relevance of these observations to the in vivo situation. to test the hypothesis that such an interaction suppresses immune responses, we studied a line of transgenic c57bl/6 mice that express the hcv core and envelope proteins in the liver. the potential effects of these proteins on the hepatic immu ... | 2001 | 11711589 |
| lutzomyia pseudolongipalpis: the first new species within the longipalpis (diptera: psychodidae: phlebotominae) complex from la rinconada, curarigua, lara state, venezuela. | lutzomyia pseudolongipalpis, the first new sand fly species within the longipalpis complex, is described based on females and males from la rinconada, curarigua, lara state, venezuela. similar to lutzomyia longipalpis sensu lato, females of the new species show spermathecae with 8-10 annulations and cibarial armature with 8-12 horizontal teeth. however, l. pseudolongipalpis females show conspicuous vertical cibarial teeth, large stipites and wing vein sections, round cerci, and short and broad v ... | 2001 | 11761375 |
| the biological function of sand fly and leishmania glycosidases. | this is a summary of the recent work on some glycosidases of sand flies and their leishmania parasites. glycosidases catalyze the hydrolysis of complex sugar subunits of polysaccharides into simple sugars. leishmania major parasites secrete chitinase and n-acetylglucosaminase, which enables them to survive in the gut of the sand fly and are important in facilitating their transmission by the phlebotomine sand fly phlebotomus papatasi. these enzymes are found in a wide range of trypanosomatids an ... | 2001 | 11770110 |
| phlebotomine sand flies in the state of piauí, brazil (diptera: psychodidae: phlebotominae). | in 1997, 1998 and 1999 we performed several captures in the state of piauí, in the counties of barro duro, campo maior, castelo, floriano, picos, são raimundo nonato and teresina. we used cdc light traps inside houses, in a primary forest and in one cave. seventeen species were collected being lutzomyia longipalpis, lutzomyia samueli, lutzomyia whitmani and lutzomyia lenti the most captured species. the genus brumptomyia, l. whitmani, lutzomyia sordellii, lutzomyia carmelinoi, lutzomyia termitop ... | 2001 | 11784927 |
| wing geometry as a tool for studying the lutzomyia longipalpis (diptera: psychodidae) complex. | 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 ... | 2001 | 11784928 |
| external morphology of sensory structures of fourth instar larvae of neotropical species of phlebotomine sand flies (diptera: psychodidae) under scanning electron microscopy. | 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 ... | 2001 | 11784930 |
| copulation songs in three siblings of lutzomyia longipalpis (diptera: psychodidae). | we present the results of recording male courtship songs of the sandfly lutzomyia longipalpis. the striking differences in the songs from 3 brazilian populations of this sandfly with 3 distinct male pheromones support the 3 sibling species previously proposed based on this characteristic. | 2006 | 11925981 |
| the d7 family of salivary proteins in blood sucking diptera. | the d7 subfamily of salivary proteins is widespread in blood sucking diptera and belongs to the superfamily of pheromone/odourant binding proteins. although d7 proteins are among the most abundant salivary proteins in adult female mosquitoes and sand flies, their role in blood feeding remains elusive. in the present work we report the sequence of seventeen novel d7 proteins, and propose an evolutionary scenario for the appearance of the several forms of this protein, based on a total of twenty-o ... | 2002 | 11966880 |
| distribution of putative male sex pheromones among lutzomyia sandflies (diptera: psychodidae). | male lutzomyia longipalpis produce terpene sex pheromones in glandular tissue underlying the cuticle. the pheromones are transmitted to the surface via cuticle-lined ducts (measuring 0.25 microm in diameter), each of which reaches the surface in the centre of a papule (measuring 3-3.5 microm in diameter). similar papules, in a range of shapes but all characterized by the presence of a central pore and absence of macroserae, occur in some other species of sandfly. the aim of the present study was ... | 2002 | 11989537 |
| canine visceral leishmaniasis: dog infectivity to sand flies from non-endemic areas. | canine visceral leishmaniasis (vl), caused by leishmania infantum (leishmania chagasi in the new world), is a zoonotic, endemic disease in western europe and latin america. the potential spreading to new regions was suggested by the appearance of canine vl among foxhounds in the us. although the sand fly vectors in the major foci of transmission have been described, no information exists on other sand flies that could propagate the infection outside endemic areas. we evaluated the capacity of lu ... | 2002 | 12002643 |
| leishmania chagasi: lipophosphoglycan characterization and binding to the midgut of the sand fly vector lutzomyia longipalpis. | during metacyclogenesis of leishmania in its sand fly vector, the parasite differentiates from a noninfective, procyclic form to an infective, metacyclic form, a process characterized by morphological changes of the parasite and also biochemical transformations in its major surface lipophosphoglycan (lpg). this glycoconjugate is polymorphic among species with variations in sugars that branch off the conserved gal(beta 1,4)man(alpha 1)-po(4) backbone of repeat units and the oligosaccharide cap. l ... | 2002 | 12034455 |
| the role of promastigote secretory gel in the origin and transmission of the infective stage of leishmania mexicana by the sandfly lutzomyia longipalpis. | transmission of leishmaniasis is effected by a specific developmental stage, the metacyclic promastigote. the precursors of metacyclic promastigotes were a distinct subpopulation of parasites, identified for the first time as a new stage in the life-cycle and named leptomonad promastigotes. microdissection of infected sandflies into 4 midgut regions and foregut allowed precursor-product relationships to be established for amastigote-procyclic promastigote, procyclic-nectomonad promastigote, nect ... | 2002 | 12049412 |
| histochemical localization of n-acetyl-galactosamine in the midgut lutzomyia longipalpis (diptera: psychodidae). | the binding of lectins to the midgut of the female sand fly lutzomyia longipalpis (lutz & neiva) was investigated using lectin-gold conjugates. midguts from laboratory-reared flies provided fructose solution and/or blood fed on hamster were dissected at 6, 24, and 48 h and at 5 and 7 d after feeding. before examination by transmission electron microscopy, each midgut was sectioned, incubated with lectins from four sources (canavalia ensiformis [cona], helix pomata agglutinin [hpa], peanut agglut ... | 2002 | 12061436 |
| impact of habitat degradation on phlebotominae (diptera: psychodidae) of tropical dry forests in northern colombia. | we examined changes in the phlebotomine fauna resulting from human intervention in a tropical dry forest of northern colombia where visceral and cutaneous leishmaniases are endemic. a natural forest reserve (colosó) and a highly degraded area (san andrés de sotavento [sas]) were sampled monthly for 8 mo using shannon traps, sticky traps, and resting-site collections. overall abundances were higher in colosó (15,988) than in sas (2,324). and species richness of phlebotomines was greater in the fo ... | 2002 | 12061439 |
| phenol red method for measuring the ph of the gut contents in lutzomyia longipalpis (psychodidae:diptera). | to develop a method to estimate the ph of the gut contents of female sandflies using a microcapillary feeding technique. | 1998 | 12078212 |
| rapid identification of mitochondrial cytochrome b haplotypes by single strand conformation polymorphism in lutzomyia longipalpis (diptera: psychodidae) populations. | newly designed primers amplified a 365-bp fragment including the 3' end of mitochondrial cytochromeb (cyt b). field collected specimens of the sand fly, lutzomyia longipalpis (lutz and neiva), from two brazil locations provided test dna. the primers, based on consensus sequences from a taxonomic spectrum of arthropods, have also amplified dna successfully from lutzomyia shannoni dyar, lutzomyia cruzi (mangabeira), and the mosquito aedes albopictus (skuse). single strand conformation polymorphism ... | 2002 | 12144306 |
| the period gene and genetic differentiation between three brazilian populations of lutzomyia longipalpis. | lutzomyia longipalpis (diptera: psychodidae: phlebotominae), the main vector of visceral leishmaniasis in the americas, is a putative species complex. molecular polymorphism was characterized in a 266 bp fragment of l. longipalpis homologous to period, a 'speciation gene' from drosophila. samples from the brazilian localities of jacobina (ba), lapinha (mg) and natal (rn) were analysed and the data indicate that the three populations are highly differentiated, with a very low level of gene flow b ... | 2002 | 12144696 |
| [standardization of the method proposed by the world health organization for determining the susceptibility levels of leishmaniasis vectors to insecticides]. | the who method for determining insecticide resistance was standardized for several species of lutzomyia sand flies under laboratory and field conditions. the biological assays were applied solely to optimize the conditions for the control, i.e., without insecticide, and to estimate mortality due to handling or other unfavorable conditions. adult female flies from 3 laboratory colonies and one field strain were tested: two laboratory strains of lutzomyia longipalpis, one laboratory strain of lutz ... | 2002 | 12152485 |
| impact of the el niño/southern oscillation on visceral leishmaniasis, brazil. | we used time-series analysis and linear regression to investigate the relationship between the annual niño-3 index from 1980 to 1998 and the annual incidence of visceral leishmaniasis (vl) in the state of bahia, brazil, during 1985-1999. an increase in vl incidence was observed in the post-el niño years 1989 (+38.7%) and 1995 (+33.5%). the regression model demonstrates that the previous year's mean niño-3 index and the temporal trend account for approximately 50% of the variance in the annual in ... | 0 | 12194766 |
| molecular divergence in the period gene between two putative sympatric species of the lutzomyia longipalpis complex. | 2002 | 12200489 | |
| practical approach for typing strains of leishmania infantum by microsatellite analysis. | currently the universally accepted standard procedure for characterizing and identifying strains of leishmania is isoenzyme analysis. however, in the mediterranean area, despite their very wide geographical distribution, most leishmania infantum strains belong to zymodeme mon-1. in order to increase our understanding of polymorphism in strains of l. infantum, we developed pcr assays amplifying 10 microsatellites and sequenced pcr products. the discriminative power of microsatellite analysis was ... | 2002 | 12202583 |
| genome-wide analysis of the odorant-binding protein gene family in drosophila melanogaster. | olfaction is of considerable importance to many insects in behaviors critical for survival and reproduction, including location of food sources, selection of mates, recognition of colony con-specifics, and determination of oviposition sites. an ubiquitous, but poorly understood, component of the insect's olfactory system is a group of odorant-binding proteins (obps) that are present at high concentrations in the aqueous lymph surrounding the dendrites of olfactory receptor neurons. obps are beli ... | 0 | 12213773 |
| preliminary assays indicate that antonia ovata (loganiaceae) and derris amazonica (papilionaceae), ichthyotoxic plants used for fishing in roraima, brazil, have an insecticide effect on lutzomyia longipalpis (diptera: psychodidae: phlebotominae). | laboratory-reared lutzomyia longipalpis (lutz and neiva 1912) was tested with extracts of two ichthyotoxic plants, known as timbós, used as fishing poison in the amazon. phlebotomines, l. longipalpis, and plants, antonia ovata and derris amazonica, were collected in the raposa-serra do sol indian reserve, a focus of visceral leishmaniasis in the state of roraima, brazil. extracts were prepared from dried leaves of a. ovata and roots of d. amazonica that were percolated in water, filtered and dri ... | 2002 | 12219144 |
| molecular determinants and regulation of leishmania virulence. | a leishmania model to explain microbial virulence in chronic infectious diseases is proposed. all these diseases progress from infection to symptomatic phase to host death or recovery. the outcome of each phase is depicted to result from the interactions of a distinct group of parasite molecules with a specific host immune compartment. the first group consists of invasive/evasive determinants, which are largely parasite cell surface and secreted molecules. their activities help parasites establi ... | 2002 | 12234388 |
| preliminary description of a new entomoparasitic nematode infecting lutzomyia longipalpis sand fly, the vector of visceral leishmaniasis in the new world. | phlebotomine sandflies are vectors of important pathogens world-wide, including leishmania spp. in the neotropics. entomoparasites have been described from phlebotomines, including virus, bacteria, protozoa, fungi, nematodes, and mites, some of which are capable of killing the host. in the present study, interference, fluorescence, and scanning electron microscopies were used for the first time to detect and morphologically characterize a new entomoparasite infecting lutzomyia longipalpis. sever ... | 2002 | 12234540 |
| infectiousness in a cohort of brazilian dogs: why culling fails to control visceral leishmaniasis in areas of high transmission. | the elimination of seropositive dogs in brazil has been used to control zoonotic visceral leishmaniasis but with little success. to elucidate the reasons for this, the infectiousness of 50 sentinel dogs exposed to natural leishmania chagasi infection was assessed through time by xenodiagnosis with the sandfly vector, lutzomyia longipalpis. eighteen (43%) of 42 infected dogs became infectious after a median of 333 days in the field (105 days after seroconversion). seven highly infectious dogs (17 ... | 2002 | 12402201 |
| seroconversion against lutzomyia longipalpis saliva concurrent with the development of anti-leishmania chagasi delayed-type hypersensitivity. | antibody responses to salivary gland sonicate (sgs) from lutzomyia longipalpis were investigated using serum samples from individuals living in an area where visceral leishmaniasis is endemic. individuals were classified into 2 groups, according to the alteration of their responses to leishmania chagasi antigen over the course of 6 months. group 1 included children who experienced anti-l. chagasi seroconversion from negative to positive; group 2 included children who experienced delayed-type hyp ... | 2002 | 12404176 |
| [definition of appropriate temperature and storage conditions in the detection of leishmania dna with pcr in phlebotomine flies]. | for epidemiological studies and control programs of leishmaniasis, taxonomic identification of the etiologic agent of the disease in the insect vector is of critical importance. the implementation of molecular techniques such as the polymerase chain reaction (pcr) has permitted great advances in the efficacy and sensitivity of parasite identification. previously, these investigations involved labor-intensive dissections and required expert personnel. the present work evaluates the effects of sto ... | 2002 | 12404930 |
| maxadilan, the vasodilator/immunomodulator from lutzomyia longipalpis sand fly saliva, stimulates haematopoiesis in mice. | protozoal parasites of the genus leishmania are transmitted to their vertebrate host within the saliva of the sand fly during a blood meal. the saliva of the sand fly lutzomyia longipalpis contains maxadilan, a potent vasodilator and immunomodulator. maxadilan has been shown to enhance the virulence of l. major in all strains of laboratory mice when injected along with the organism. increased haematopoiesis has been associated with enhanced susceptibility to leishmania organisms. here, we show t ... | 2002 | 12406198 |
| salivary gland hyaluronidase in various species of phlebotomine sand flies (diptera: psychodidae). | hyaluronidase activity was detected and partially characterized in salivary gland extracts of females of six sand fly species. in phlebotomus papatasi and lutzomyia longipalpis the enzyme was active over a broad ph range; the ph optimum was 5.0. besides high cleaving activity towards hyaluronic acid, it hydrolyzed chondroitin sulfates a and c. hyaluronidases of various sand fly species differed in structure and sensitivity to reducing conditions. in the subgenera phlebotomus (p. papatasi and p. ... | 2002 | 12429121 |
| assessment of pcr in the detection of leishmania spp in experimentally infected individual phlebotomine sandflies (diptera: psychodidae: phlebotominae). | dna amplification by the polymerase chain reaction (pcr) was applied in the investigation of the presence of leishmania (kinetoplastida: trypanosomatidae) parasites in single phlebotomine sandflies. three phlebotomine/parasite pairs were used: lutzomyia longipalpis/leishmania chagasi, lutzomyia migonei/leishmania amazonensis and lutzomyia migonei/leishmania braziliensis, all of them incriminated in the transmission of visceral or cutaneous leishmaniasis. dna extraction was performed with whole i ... | 2002 | 12436164 |
| low infectiousness of a wildlife host of leishmania infantum: the crab-eating fox is not important for transmission. | the epidemiological role of the crab-eating fox cerdocyon thous in the transmission of leishmania infantum is assessed in a longitudinal study in amazon brazil. a total of 37 wild-caught foxes were immunologically and clinically monitored, and 26 foxes exposed to laboratory colonies of the sandfly vector lutzomyia longipalpis, over a 15-month period. in total 78% (29/37) of foxes were seropositive for anti-leishmania igg on at least 1 occasion, and 38% (8/37) had infections confirmed by pcr and/ ... | 2002 | 12458824 |
| the salivary purine nucleosidase of the mosquito, aedes aegypti. | a cdna clone originating from adult female aedes aegypti mosquitoes was found with substantial similarity to nucleosidases of the ec 3.2.2.1 enzyme class. although this type of enzyme is unusual in animals, abundant enzyme activity was found in salivary homogenates of this mosquito, but not in salivary homogenates of the mosquitoes anopheles gambiae and culex quinquefasciatus, or the sand fly lutzomyia longipalpis. aedes salivary homogenate hydrolyses inosine and guanosine to hypoxanthine and xa ... | 2003 | 12459196 |
| characterization of the lectin from females of phlebotomus duboscqi sand flies. | lectin from females of the important sand fly vector, phlebotomus duboscqi (diptera: psychodidae), was isolated by immunoaffinity chromatography using a minicolumn with immobilized anti-lectin immunoglobulins. carbohydrate-binding specificity of active fractions corresponded to that of midgut and salivary gland lysates. haemagglutination was inhibited by d-glucosamine, d-galactosamine and d-mannosamine. the homogeneity and molecular mass of the purified lectin was examined by sds/page in both re ... | 2002 | 12473126 |
| intradermal infection model for pathogenesis and vaccine studies of murine visceral leishmaniasis. | the levels of protection found in vaccine studies of murine visceral leishmaniasis are significantly lower than for cutaneous leishmaniasis; whether this is due to the high-challenge murine model employed and/or is a consequence of differences required in tissue-specific local immune responses is not understood. consequently, an intradermal murine model of visceral leishmaniasis has been explored. intradermal inoculation established a chronic infection in susceptible mice which was associated wi ... | 2003 | 12496190 |
| role of the domestic chicken (gallus gallus) in the epidemiology of urban visceral leishmaniasis in brazil. | zoonotic visceral leishmaniasis (zvl) is a serious public health problem in several brazilian cities. although the proximity of chicken houses is often cited as a risk factor in studies of urban zvl, the role chickens play in the epidemiology of the disease has not been defined. chickens attract both male and female sand flies (lutzomyia longipalpis) but are unable to sustain leishmania infections, and their presence may exert a zooprophylactic effect. we discuss environmental, physiologic, soci ... | 2002 | 12498667 |
| comparative vectorial efficiency of lutzomyia evansi and lu. longipalpis for transmitting leishmania chagasi. | 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 f ... | 2003 | 12505180 |
| ecology of american cutaneous leishmaniasis in the state of rio de janeiro, brazil. | a study of the sand fly fauna was carried out in the endemic area ofamerican cutaneous leishmaniasis (acl) in the municipality of mesquita, state of rio de janeiro, in an area where dwellings (with humans and dogs infected by leishmania (viannia) braziliensis) have been recently visited by sloths. weekly captures were made during two consecutive years in two different sites (1 m and 600 m above sea level) and in three different habitats in each site (domestic, extra-domestic and sylvatic) using ... | 2002 | 12546456 |
| molecular characterization of llchit1, a midgut chitinase cdna from the leishmaniasis vector lutzomyia longipalpis. | during development within the midgut of the sand fly vector, leishmania parasites after undergoing differentiation and multiplication must escape the peritrophic matrix (pm). although leishmania chitinase is believed to take part in promoting the escape of the parasite from the pm by inducing degradation of chitin fibers, it is conceivable that a sand fly-derived chitinase can also have a role in such an event. here we describe the molecular cloning and partial characterization of a complete cdn ... | 2003 | 12609513 |
| genetic characterization of glucose transporter function in leishmania mexicana. | both insect and mammalian life cycle stages of leishmania mexicana take up glucose and express all three isoforms encoded by the lmgt glucose transporter gene family. to evaluate glucose transporter function in intact parasites, a null mutant line has been created by targeted disruption of the lmgt locus that encompasses the lmgt1, lmgt2, and lmgt3 genes. this deltalmgt null mutant exhibited no detectable glucose transport activity. the growth rate of the deltalmgt knockout in the promastigote s ... | 2003 | 12651954 |
| [approximation to the cdc method to determine insecticide susceptibility in leishmaniasis vectors]. | the centers for disease control (cdc, usa) has proposed a simplified method for the determinations of insecticide resistance in adult mosquitoes, using 250 ml wheaton bottles containing measured dosages. insects are transferred into the bottle for 1 hour and monitored for mortality at regular intervals. in standardizing the cdc method for use with phlebotomine sand flies, effects of the solvent without insecticide were evaluated. two colonized sand fly vector species were used: lutzomyia longipa ... | 2003 | 12696404 |
| canine visceral leishmaniasis in barra de guaratiba, rio de janeiro, brazil: assessment of risk factors. | barra de guaratiba is a coastal area of the city of rio de janeiro where american visceral leishmaniasis (avl) is endemic. although control measures including killing of dogs and use of insecticides have been applied at this locality, the canine seroprevalence remains at 25% and during 1995 and 1997 eight autochthonous human cases were notified. in order to evaluate factors related to the increase of the risk for leishmania (leishmania) chagasi infection in dogs we have screened 365 dogs by anti ... | 2003 | 12754572 |
| a follow-up of beagle dogs intradermally infected with leishmania chagasi in the presence or absence of sand fly saliva. | in this study, we compare the development of infection and/or disease in beagle dogs intradermally infected with leishmania chagasi, in the presence or absence of lutzomyia longipalpis saliva, with those of intravenously infected animals. spleen samples of all the animals inoculated with parasites had positive polymerase chain reaction tests for leishmania dna. positive spleen cultures for leishmania were detected earlier (p < or = 0.018) and were more frequent (five out of the five animals) in ... | 2003 | 12781472 |
| phylogeography of the neotropical sand fly lutzomyia longipalpis inferred from mitochondrial dna sequences. | sand flies in the lutzomyia longipalpis species complex include the primary vector of leishmania chagasi, the etiologic agent of visceral leishmaniasis in the neotropics. twelve l. longipalpis populations from south and central america were compared using the cytochrome c oxidase i (coi) gene from the mitochondrial genome. the haplotype profiles for each population revealed that the majority of sequence variation was inter-population (98%) rather than intra-population, suggesting that sequence p ... | 2002 | 12797984 |
| genetic identification of two sibling species of lutzomyia longipalpis (diptera: psychodidae) that produce distinct male sex pheromones in sobral, ceará state, brazil. | lutzomyia longipalpis, the main sandfly vector for new world visceral leishmaniasis is a complex of an as yet undefined number of sibling species. at present, there is no consensus on the status (single species vs. species complex) of brazilian populations. we applied five microsatellite loci to test the hypothesis that l. longipalpis occurs as two sympatric cryptic species in sobral, ceará state, brazil as predicted by male sex pheromone chemotypes described previously for field specimens from ... | 2003 | 12803639 |
| [pcr as a tool in confirming the experimental transmission of leishmania chagasi to hamsters by lutzomyia longipalpis (diptera:psychodidae)]. | the use of pcr (polymerase chain reaction) was evaluated for its effectiveness as a tool in the detection of transmission of leishmania chagasi to a hamster host, mesocricetus auratus, by insect vector bite. two pairs of uninfected and anesthetized hamsters were introduced into cages containing infected females of the typical phlebotomine sand fly vector, lutzomyia longipalpis. the flies were experimentally infected with leishmania chagasi and the infection was verified by dissection of subsampl ... | 2003 | 12872564 |
| anti-complement activity in the saliva of phlebotomine sand flies and other haematophagous insects. | 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 fo ... | 2003 | 12885192 |
| navigation of lutzomyia longipalpis (diptera: psychodidae) under dusk or starlight conditions. | the responses of male and female lutzomyia longipalpis (lutz & neiva) to different wavelengths of light was tested by presenting the sandflies with two light sources simultaneously, a series of test wavelengths between 350-670 nm and a 400 nm control. to test whether l. longipalpis could discriminate between the test and control, three sets of experiments were carried out in which the test wavelengths were presented at higher, equivalent or lower intensity than the control. in all three experime ... | 2003 | 12908917 |
| immunomodulatory effects of maxadilan and phlebotomus papatasi sand fly salivary gland lysates on human primary in vitro immune responses. | leishmaniasis is a parasitic disease transmitted by the bite of leishmania-infected sand flies. here we show for the first time the ability of maxadilan (max), a vasodilatory peptide isolated from the sand fly lutzomyia longipalpis, and salivary gland lysate (sgl) from phlebotomus papatasi to decrease the secretion of type 1 cytokines and to enhance the production of the type 2 cytokine interleukin (il)-6 by human peripheral blood mononuclear cells (pbmc) and monocytes. we found max decreased th ... | 2003 | 12911520 |
| phlebotomus (adlerius) halepensis vector competence for leishmania major and le. tropica. | in eurasia, phlebotomine sandflies of the subgenus adlerius (diptera: psychodidae) comprise about 20 known species. some are suspected vectors of visceral leishmaniasis (vl) and at least one species has been implicated as a vector of cutaneous leishmaniasis (cl). we tested phlebotomus (adlerius) halepensis theodor (jordan strain) for cl vector competence, compared with three standard vectors: phlebotomus (phlebotomus) duboscqi n-l. from senegal, phlebotomus (paraphlebotomus) sergenti parrot from ... | 2003 | 12941007 |
| lutzomyia longipalpis (diptera: psychodidae: phlebotominae): a review. | 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 b ... | 2003 | 12947480 |
| abortive infection of lutzomyia longipalpis insect vectors by aflagellated ldarl-3a-q70l overexpressing leishmania amazonensis parasites. | leishmania donovani adp-ribosylation factor-like protein 3a (ldarl-3a) is a small g protein isolated from the protozoan parasite l. donovani with no defined physiological function. previously [cuvillier, a., redon, f., antoine, j.-c., chardin, p., devos, t., and merlin, g. (2000) j cell sci 113: 2065-2074] we have shown that overexpression in l. amazonensis promastigotes of the mutated protein ldarl-3a-q70l, which remains constitutively associated with gtp, leads to the disappearance of the flag ... | 2003 | 12969377 |
| interaction of insect trypanosomatids with mosquitoes, sand fly and the respective insect cell lines. | interaction experiments between hematophagous insects and monoxenous trypanosomatids have become relevant, once cases of human infection involving these protozoa have been reported. moreover, investigations related to the interaction of insects with trypanosomatids that harbour an endosymbiotic bacterium and thereby lack the paraflagellar rod structure are important to elucidate the role of this structure in the adhesion process. in this work, we compared the interaction of endosymbiont-bearing ... | 2003 | 13129523 |
| two separate growth phases during the development of leishmania in sand flies: implications for understanding the life cycle. | the life cycle of leishmania alternates between two main morphological forms: intracellular amastigotes in the mammalian host and motile promastigotes in the sand fly vector. several different forms of promastigote have been described in sandfly infections, the best known of these being metacyclic promastigotes, the mammal-infective stages. here we provide evidence that for leishmania (leishmania) mexicana and leishmania (leishmania) infantum (syn. chagasi) there are two separate, consecutive gr ... | 2003 | 13129524 |
| the presence of lutzomyia longipalpis in a focus of american visceral leishmaniasis where the only proven vector is lutzomyia cruzi. corumbá, mato grosso do sul state. | the present communication reports the presence of lutzomyia longipalpis in corumbá, mato grosso do sul, where the principal vector is lutzomyia cruzi. | 2003 | 14576882 |
| evidence for the involvement of vpac1 and vpac2 receptors in pressure-induced vasodilatation in rodents. | a transient increase in skin blood flow in response to an innocuous local pressure application, defined as pressure-induced vasodilatation (piv), delays the occurrence of ischaemia, suggesting a protective feature against applied pressure. the piv response depends on capsaicin-sensitive nerve fibres and calcitonin gene-related peptide (cgrp) has been shown to be involved. in these fibres, cgrp coexists with pituitary adenylate cyclase-activating polypeptide (pacap). three distinct receptors medi ... | 2004 | 14578481 |
| horizontal stratification of the sand fly fauna (diptera: psychodidae) in a transitional vegetation between caatinga and tropical rain forest, state of bahia, brazil. | a study about the horizontal stratification of the sand fly fauna in two distinct ecosystems, caatinga area, endemic for visceral leishmaniasis, and the tropical rain forest area, endemic for cutaneous leishmaniasis, was performed in the state of bahia, brazil. lutzomyia longipalpis was predominant in the caatinga, and following it came the species l. capixaba and l. oswaldoi. in the tropical rain forest other species were found, such as l. intermedia, l. migonei, l. whitmani, l. yuilli, l.fisch ... | 2003 | 14595447 |
| the taxonomic status of genetically divergent populations of lutzomyia longipalpis (diptera: psychodidae) based on the distribution of mitochondrial and isozyme variation. | 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 ... | 2003 | 14596274 |
| physiological consequences of drug resistance in leishmania and their relevance for chemotherapy. | in the early twentieth century, infectious diseases were a leading cause of death worldwide. through the following years, morbidity and mortality caused by infectious diseases decreased considerably in the developed world, but not in the developing world, where infectious diseases remain an important reason for concern. for example, leishmaniosis has become into a serious third world problem. this is mainly due to an increasing frequency of drug-resistance in leishmania and an enhanced risk of c ... | 2003 | 14613496 |
| mitochondrial cytochrome b variation in populations of the visceral leishmaniasis vector lutzomyia longipalpis across eastern brazil. | a population analysis of peridomestic, light-trapped, field specimens of the phlebotomine sand fly lutzomyia longipalpis was targeted to six locations representing a geographic transect across eastern brazil. mitochondrial cytochrome b gene sequences established the pattern of genetic variation among the populations. alignment of a 261-basepair region at the 3' end of cytochrome b identified 30 haplotypes and 21 segregating sites from 78 sand flies. pairwise comparisons indicated statistically s ... | 2003 | 14640498 |
| control trial of lutzomyia longipalpis s.l. in the island of margarita, venezuela. | 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 tri ... | 2003 | 14641849 |
| [blood feeding sources and peridomiciliation of lutzomyia longipalpis (lutz & neiva, 1912) (psychodidae, phlebotominae)]. | 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, maranh o 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 dwelling ... | 2003 | 14666218 |
| allomonal effect of breath contributes to differential attractiveness of humans to the african malaria vector anopheles gambiae. | background: removal of exhaled air from total body emanations or artificially standardising carbon dioxide (co2) outputs has previously been shown to eliminate differential attractiveness of humans to certain blackfly (simuliidae) and mosquito (culicidae) species. whether or not breath contributes to between-person differences in relative attractiveness to the highly anthropophilic malaria vector anopheles gambiae sensu stricto remains unknown and was the focus of the present study. methods: the ... | 2004 | 14748930 |
| sand fly saliva enhances leishmania amazonensis infection by modulating interleukin-10 production. | after transmission through the bite of female sand flies, leishmania spp. can cause a broad spectrum of disease manifestations collectively known as leishmaniases. l. amazonensis is endemic in south america, where it causes cutaneous, diffuse cutaneous, and visceral leishmaniasis. in this study, we have provided evidence that salivary gland extracts (sge) of lutzomyia longipalpis enhances l. amazonensis infection. balb/c mice infected intradermally in the ear with 10(5) metacyclic promastigotes ... | 2004 | 14977924 |
| lutzomyia longipalpis salivary gland homogenate impairs cytokine production and costimulatory molecule expression on human monocytes and dendritic cells. | in this report, we describe an investigation of the effects of lutzomyia longipalpis sand fly salivary gland homogenates (sgh) on cytokine production and expression of costimulatory molecules on human monocytes, macrophages (mphis), and dendritic cells (dcs). sgh of l. longipalpis induced an increase in interleukin-6 (il-6), il-8 and il-12p40 production but a decrease in tumor necrosis factor alpha and il-10 production by lipopolysaccharida (lps)-stimulated monocytes. we also examined the expres ... | 2004 | 14977931 |
| [absence of lutzomyia longipalpis in some endemic visceral leishmaniasis areas in rio de janeiro municipality]. | 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 de ... | 2004 | 14999355 |
| negative effect of antibodies against maxadilan on the fitness of the sand fly vector of american visceral leishmaniasis. | lutzomyia longipalpis expresses a salivary protein called maxadilan (max) that functions to dilate vertebrate blood vessels and thereby to facilitate the sand fly's acquisition of blood. we hypothesized that antibodies specific for one of many max variants would inhibit vasodilatory function of that variant. in vitro and in vivo experiments showed that antibodies against a specific max variant decreased vasodilatory function. more specifically, antibodies against max blocked vasodilation of a co ... | 2004 | 15031517 |
| antigenic diversity in maxadilan, a salivary protein from the sand fly vector of american visceral leishmaniasis. | the salivary protein maxadilan (max) is a vasodilator and immunomodulator from the sand fly vector of the protozoan parasite leishmania chagasi. vaccinating balb/c mice with sand fly salivary gland extracts or with max protects the host against l. major infection. because of the potential use of max in an anti-leishmania vaccine, we characterized the vertebrate host igg response to max in the present study. our immunochemical analysis indicated that antibodies to max were detected in balb/c mice ... | 2004 | 15031518 |
| [experimental infection of equus asinus with leishmania chagasi cunha & chagas, 1937]. | 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 8t ... | 2003 | 15049109 |
| mosquito appetite for blood is stimulated by plasmodium chabaudi infections in themselves and their vertebrate hosts. | arthropod vectors of disease may encounter more than one infected host during the course of their lifetime. the consequences of super-infection to parasite development are rarely investigated, but may have substantial epidemiological and evolutionary consequences. | 2004 | 15151700 |
| down-regulation of gp63 in leishmania amazonensis reduces its early development in lutzomyia longipalpis. | the zinc protease (gp63) of promastigotes was found to play a role in the sand fly part of the leishmania life cycle. lutzomyia longipalpis females were fed with promastigotes (10(6) per ml) of a leishmania amazonensis clone whose gp63 was up- and down-regulated by directional cloning into p6.5 for sense- and anti-sense transcription. early development was found to differ significantly between the sense- and anti-sense transfectants 2 days post-feeding. the sense transfectants overexpressing gp6 ... | 2004 | 15158771 |
| distribution of phlebotomine sand flies (diptera: psychodidae) in the state of rio grande do norte, brazil. | visceral and cutaneous leishmaniasis are major endemic diseases in northeast brazil. the objective of the current study was to determine the species and geographic distribution of potential sand fly vectors of leishmania in the state of rio grande do norte. sand flies were captured using cdc light traps in 30 municipalities distributed throughout the 8 geographic zones of the state. twelve lutzomyia species were identified. lutzomyia longipalpis lutz & neiva was the most prevalent and accounted ... | 2000 | 15218921 |
| visceral leishmaniasis caused by leishmania infantum in a spanish patient in argentina: what is the origin of the infection? case report. | the question "where have you been?" is a common one asked by doctors in northern europe and america when faced with clinical symptoms not typical of their country. this question must also arise in the clinics of developing countries in which non-autochthonous cases such as the one described here can appear. important outbreaks of leishmania infantum have been recorded in the last decade in several latin american countries but its presence has not yet been recorded in argentina. we report the fir ... | 2004 | 15225352 |
| transmission of cutaneous leishmaniasis by sand flies is enhanced by regurgitation of fppg. | sand flies are the exclusive vectors of the protozoan parasite leishmania, but the mechanism of transmission by fly bite has not been determined nor incorporated into experimental models of infection. in sand flies with mature leishmania infections the anterior midgut is blocked by a gel of parasite origin, the promastigote secretory gel. here we analyse the inocula from leishmania mexicana-infected lutzomyia longipalpis sand flies. analysis revealed the size of the infectious dose, the underlyi ... | 2004 | 15269771 |
| pacap modulation of the colon-inferior mesenteric ganglion reflex in the guinea pig. | we investigated the effect of pituitary adenylate cyclase activating peptide (pacap) on the colon-inferior mesenteric ganglion (img) reflex loop in vitro. pacap27 and pacap38 applied to the img caused a prolonged depolarization and intense generation of fast epsps and action potentials in img neurones. activation of pacap-preferring receptors (pac1-rs) with the selective agonist maxadilan or vasoactive intestinal peptide (vip)/pacap (vpac) receptors with vip produced similar effects whereas prio ... | 2004 | 15284351 |
| [lutzomyia whitmani periurbanization in a focus of cutaneous leishmaniasis in the state of maranhão, brazil]. | an entomological survey was performed in the periurban area of the municipality of dom pedro in the state of maranhão in 2000, in order to estimate the abundance of lutzomyia longipalpis, due to the occurrence of one suspect death caused by kala azar. however, it was surprisingly verified that 82.4% (2,440 specimens) from the total of 2,961 sand flies captured in the peridomicile were lutzomyia whitmani. this association has indicated a new pattern for cutaneous leishmaniasis transmission (urban ... | 2004 | 15330071 |
| [visceral leishmaniasis among indians of the state of roraima, brazil: clinical and epidemiologic aspects of the cases observed from 1989 to 1993]. | a description of the epidemiological profile of visceral leishmaniasis among indians in the state of roraima, brazil, was based on the clinical characteristics of human and dog disease, ecological aspects of the area where the cases occurred and entomologic investigations performed from 1989 to 1993. the 82 human cases were reported in six out of eight counties that existed then in the state; there was a 69.5% predominance of male cases among those registered and a greater (52.4%) occurrence of ... | 2004 | 15334263 |