| a simple technique for mass rearing lutzomyia longipalpis and phlebotomus papatasi (diptera: psychodidae) in the laboratory. | | 1983 | 6644754 |
| replication of rift valley fever virus in the sand fly lutzomyia longipalpis. | rift valley fever virus was shown to replicate in lutzomyia longipalpis after intrathoracic inoculation. viral titers peaked at approximately 4 days postinoculation [mean titer = 10(4.0) plaque forming units (pfu)] and remained relatively constant through day 7. a minimum of 6 of 326 sand flies transmitted virus by bite to susceptible hamsters after 5-9 days of extrinsic incubation. viral titers of sand flies exposed per os declined steadily through day 9. none of 378 flies that had ingested app ... | 1984 | 6711746 |
| receptors for the vasodilator maxadilan are expressed on selected neural crest and smooth muscle-derived cells. | maxadilan is a potent vasodilator peptide isolated from salivary glands of the blood feeding sand fly lutzomyia longipalpis. the peptide relaxes rabbit aortic rings in an endothelium independent manner while elevating levels of camp and has been found to bind to membrane homogenates from brain. these studies on tissues have now been expanded with an examination of binding and signaling of maxadilan to a number of established cell lines and primary cultures. the data reveal that maxadilan binds t ... | 1996 | 9035385 |
| the sandfly lutzomyia longipalpis shows specific humoral responses to bacterial challenge. | the presence of immune molecules induced by microorganisms in the haemolymph of lutzomyia longipalpis sandflies has been investigated. injections of escherichia coli and micrococcus luteus into female sandflies induced anti-bacterial activity in the haemolymph. inhibition zone assays showed that haemolymph from e. coli and m.luteus injected sandflies differentially inhibited m.luteus growth. this differential effect was specific to m.luteus infection since anti-e.coli activity was similar in hae ... | 1997 | 9430110 |
| filamentous proteophosphoglycan secreted by leishmania promastigotes forms gel-like three-dimensional networks that obstruct the digestive tract of infected sandfly vectors. | development of leishmania parasites in the digestive tract of their sandfly vectors involves several morphological transformations from the intracellular mammalian amastigote via a succession of free and gut wall-attached promastigote stages to the infective metacyclic promastigotes. at the foregut midgut transition of leishmania-infected sandflies a gel-like plug of unknown origin and composition is formed, which contains high numbers of parasites, that occludes the gut lumen and which may be r ... | 1999 | 10569240 |
| isozymic and metric variation in the lutzomyia longipalpis complex. | male lutzomyia longipalpis of two types from bolivia were compared using isozyme electrophoresis and wing morphometry. one sample (ex chiflonkaka cave, alt. 2800 m at toro toro, charcas province, potosi department) was 'two-spot' phenotype males (i.e. tergites iii and iv with paired pale patches of pheromone glands), whereas two other locality samples (apa apa and imanaco, sud yungas province, la paz department) were one-spot male phenotype (only tergite iv with paired pale patches). multilocus ... | 1997 | 9430121 |
| larval microhabitats of lutzomyia longipalpis (diptera: psychodidae) in an endemic focus of visceral leishmaniasis in colombia. | 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 ... | 1997 | 9439128 |
| the vasoactive peptide maxadilan from sand fly saliva inhibits tnf-alpha and induces il-6 by mouse macrophages through interaction with the pituitary adenylate cyclase-activating polypeptide (pacap) receptor. | maxadilan is a vasodilatory peptide encoded by a gene cloned from lutzomyia longipalpis salivary glands. in this study we investigated the effects of maxadilan on macrophage functions. maxadilan treatment of lps-stimulated balb/c macrophages inhibited tnf-alpha release but increased il-6. further, it also induced il-6 release in a dose-dependent manner from unstimulated macrophages. maxadilan increased production of pge2, and the inhibition of tnf-alpha was completely abrogated by indomethacin. ... | 1998 | 9469441 |
| susceptibility of lutzomyia longipalpis (diptera: psychodidae) to selected insecticides in an endemic focus of visceral leishmaniasis in venezuela. | a field population of lutzomyia longipalpis from la rinconada, lara state, an endemic focus of visceral leishmaniasis in venezuela, was tested for susceptibility to organochlorine (ddt 2%), carbamate (propoxur 0.01%), organophosphate (malathion 2%, fenitrothion 1%, and pirimiphos methyl 1%), and pyrethroid (deltamethrin 0.06%, lambdacyhalothrin 0.06%, and permethrin 0.2%) insecticides. susceptibility to the insecticides tested was evaluated in the field population of l. longipalpis and compared ... | 1997 | 9474559 |
| genetic variability among populations of the sand fly lutzomyia (lutzomyia) longipalpis (diptera: psychodidae) from central america. | eleven central american populations of lutzomyia longipalpis (lutz & neiva) were analyzed for genetic variation at 16 enzyme loci. the aim was to study the genetic structure among populations within this region and to identify demes that may represent different sibling species. genotypic frequencies within populations agreed with hardy-weinberg expectations, indicating that there were no sympatric sibling species among these 11 populations. levels of genetic distance between pairs of populations ... | 1998 | 9538579 |
| genetic structure of local populations of lutzomyia longipalpis (diptera: psychodidae) in central colombia. | lutzomyia longipalpis (lutz & neiva), the sand fly vector of american visceral leishmaniasis in the new world tropics, has a broad but discontinuous geographical distribution from southern mexico to argentina. a baseline for population genetic structure and genetic variability for this species was obtained by analyzing 5 local, peridomestic populations at the approximate center of its distribution, the magdalena river valley of central colombia. three populations of l. longipalpis from el callej ... | 1998 | 9542350 |
| genetics of mosquito vector competence. | mosquito-borne diseases are responsible for significant human morbidity and mortality throughout the world. efforts to control mosquito-borne diseases have been impeded, in part, by the development of drug-resistant parasites, insecticide-resistant mosquitoes, and environmental concerns over the application of insecticides. therefore, there is a need to develop novel disease control strategies that can complement or replace existing control methods. one such strategy is to generate pathogen-resi ... | 2000 | 10704476 |
| [phlebotomines (diptera: psychodidae) focusing visceral leishmaniasis in the state of mato grosso do sul, brazil]. | in the americas, lutzomyia longipalpis has been incriminated as the vector of visceral leishmaniasis in almost all the areas in which this disease has been reported. the notification of human cases of visceral leishmaniasis and the presence of dogs with an appearance suggestive of the disease in the country of corumbá, mato grosso do sul state, brazil, led us to undertake an entomological investigation in this area, for the purpose of identifying the phlebotomine vector. | 1997 | 9595767 |
| salivary gland lysate from the sand fly lutzomyia longipalpis suppresses the immune response of mice to sheep red blood cells in vivo and concanavalin a in vitro. | | 1998 | 9603500 |
| adenosine, amp, and protein phosphatase activity in sandfly saliva. | as they probe the skin for blood, sand flies inject saliva that prevents hemostasis. sand fly saliva also promotes leishmaniasis by suppressing immunologic functions of macrophages. saliva of phlebotomus papatasi, the vector of old world cutaneous leishmaniasis, contains adenosine and amp. we show that ph. papatasi saliva as well as pure adenosine down-regulate the expression of the inducible nitric oxide (no) synthase gene in activated macrophages. in addition ph. papatasi, but not lutzomyia lo ... | 2000 | 10761741 |
| [update on the geographical distribution and first record of lutzomyia longipalpis in an urban area in são paulo state, brazil]. | | 1997 | 9629719 |
| prevention of cerebral vasospasm by vasodilatory peptide maxadilan following subarachnoid hemorrhage in rabbits. | maxadilan is a vasodilatory peptide isolated from the blood-feeding sand fly lutzomyia longipalpis. its vasodilatory activity, estimated by the formation of erythema on rabbit skin, is greater than those of calcitonin gene-related peptide, vasoactive intestinal polypeptide and pituitary adenylyl cyclase activating polypeptide (pacap). we have recently demonstrated that maxadilan is a specific agonist for the pacap type i receptor, which is widely distributed in brain. therefore, we were interest ... | 1998 | 9685937 |
| genetic variation among natural and laboratory colony populations of lutzomyia longipalpis (lutz & neiva, 1912)(diptera: psychodidae) from colombia. | genetic diversity among three field populations of lutzomyia longipalpis in colombia was studied using isozyme analysis. study sites were as much as 598 km apart and included populations separated by the eastern cordillera of the andes. genetic variability among populations, estimated by heterozygosity, was within values typical for insects in general (8.1%). heterozygosity for field populations were compared with a laboratory colony from colombia (melgar colony) and were only slightly lower. th ... | 1998 | 9698845 |
| random amplified polymorphic dna (rapd) analysis of lutzomyia longipalpis laboratory populations. | the phlebotomine sand fly lutzomyia longipalpis has been incriminated as a vector of american visceral leishmaniasis, caused by leishmania chagasi. however, some evidence has been accumulated suggesting that it may exist in nature not as a single but as a species complex. our goal was to compare four laboratory reference populations of l. longipalpis from distinct geographic regions at the molecular level by rapd-pcr. we screened genomic dna for polymorphic sites by pcr amplification with decame ... | 1998 | 9713138 |
| transformation, development, and transmission of axenically cultured amastigotes of leishmania mexicana in vitro and in lutzomyia longipalpis. | axenic cultures of leishmania mexicana amastigotes were transformed to promastigotes in vitro and in vivo in lutzomyia longipalpis. in vitro, both exponential phase and stationary phase amastigotes were capable of transforming and growing as promastigotes, but exponential phase amastigotes completed this transition more quickly. in vivo, both populations were capable of establishing infections in sand flies by membrane feeding and could be transmitted to balb/c mice via bite. a variety of morpho ... | 1998 | 9749637 |
| evolution of lesion formation, parasitic load, immune response, and reservoir potential in c57bl/6 mice following high- and low-dose challenge with leishmania major. | a model of cutaneous leishmaniasis using 10(2) leishmania major metacyclic promastigotes inoculated into the footpads of genetically resistant c57bl/6 mice was studied in order to more accurately reproduce the evolution of lesion formation and the kinetics of parasite growth and immune response as they might occur in naturally exposed reservoirs and in human hosts. in contrast to the more conventional experimental model employing 10(6) metacyclic promastigotes, in which the rapid development of ... | 2000 | 10948141 |
| lutzomyia longipalpis: ph in the gut, digestive glycosidases, and some speculations upon leishmania development. | screening for digestive glycosidases in different parts of the gut and associated organs of lutzomyia longipalpis is reported. searches for the enzymes were made in blood-fed and non-blood-fed females and the enzymes were characterized as soluble or membrane-bound molecules. a total of four different activities were detected, corresponding to the following specificities: an alpha-glucosidase, an n-acetyl-beta-d-glucosaminidase, an n-acetyl-beta-d-galactosaminidase, and an alpha-l-fucosidase. the ... | 1998 | 9806865 |
| genetic polymorphism of morphological and biochemical characters in a natal, brazil, population of lutzomyia longipalpis (diptera: psychodidae). | the phlebotomine sand fly, lutzomyia longipalpis, is the vector of visceral leishmaniasis in the new world. variability in its tergal spot morphology has led to conflicting interpretations of the species status of the various forms. an l. longipalpis field population from eastern brazil was found with three co-occurring morphological variations--1-spot, 2-spot, and an intermediate form. genetic profiles were established for each form. fifteen isoenzyme loci provided the data matrix for compariso ... | 1998 | 9813825 |
| exponential fitness gains of rna virus populations are limited by bottleneck effects. | fitness is a parameter that quantitatively measures adaptation of a virus to a given environment. we have previously reported exponential fitness gains of large populations of vesicular stomatitis virus replicating in a constant environment (i. s. novella et al., proc. natl. acad. sci. usa 92:5841-5844, 1995). in this paper, we report that during long-term passage of such large viral populations, fitness values reached a high-fitness plateau during which stochastic fitness variations were observ ... | 1999 | 9882378 |
| genetic variability in biochemical characters of brazilian field populations of the leishmania vector, lutzomyia longipalpis (diptera: psychodidae). | the phlebotomine sand fly lutzomyia longipalpis is the insect vector of visceral leishmaniasis, a protozoan disease of increasing incidence and distribution in central and south america. electrophoretic allele frequencies of 15 enzyme loci were compared among the l. longipalpis populations selected across its distribution range in brazil. the mean heterozygosity of two colonized geographic strains (one each from colombia and brazil) were 6% and 13% respectively, with 1.6-1.9 alleles detected per ... | 1998 | 9886196 |
| variation in the salivary peptide, maxadilan, from species in the lutzomyia longipalpis complex. | maxadilan is an approximately 7kda peptide that occurs in the saliva of the sand fly lutzomyia longipalpis. this peptide is a potent vasodilator and may also have immunomodulatory effects related to the pathogenesis of leishmanial infections. variation in the primary dna and inferred amino acid sequence of maxadilan is reported. differences were found within and among natural field populations as well as among sibling species. extensive amino acid sequence differentiation, up to 23%, was observe ... | 1999 | 10380110 |
| the salivary apyrase of the blood-sucking sand fly phlebotomus papatasi belongs to the novel cimex family of apyrases. | apyrases are enzymes that hydrolyze nucleotide di- and triphosphates to orthophosphate and mononucleotides. at least two families of enzymes, belonging to the 5'-nucleotidase and to the actin/heat shock 70/sugar kinase superfamily, have evolved independently to serve the apyrase reaction. both families require either ca(2+) or mg(2+) for their action. a novel apyrase enzyme sequence, with no homology to any other known protein sequence, was found recently in the salivary glands of the hematophag ... | 2001 | 11136609 |
| [phlebotomus (diptera, phlebotominae) from saint luis island, maranhão gulf region, brazil]. | this study lists 32 species of sand flies, 1 of them belonging to the genus brumptomyia and 31 to the genus lutzomyia, distributed among the following subgenera: psychodopygus (6), nyssomyia (5), pressatia (3), evandromyia (2), psathyromyia (2), sciopemyia (2), lutzomyia (1), micropygomyia (1), viannamyia (1), and the groups oswaldoi (5) and migonei (3). the sand flies were captured in the wild (forest) and in peridomicile (pigpen, hen house and stable) and intradomicile (bedroom) areas from 06: ... | 1999 | 10380563 |
| 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 |
| behaviour of lutzomyia longipalpis in an area of southern honduras endemic for visceral/atypical cutaneous leishmaniasis. | the predominant sandfly in las maria de pavana, choluteca, honduras, was found to be lutzomyia longipalpis, most (69%) of the 791 specimens of this species caught being male. when local lu. longipalpis were studied over 1 year (1986-1987) using cdc traps, peaks in the size of the adult population were observed in december and july, each after a period of rain. most [51% (24/47)-67% (97/144)] of the flies caught inside houses were female whereas most [55% (6/11)-56% (37/66)] of those caught outsi ... | 1998 | 10396347 |
| infectivity of plasmodium berghei sporozoites delivered by intravenous inoculation versus mosquito bite: implications for sporozoite vaccine trials. | plasmodium berghei sporozoites delivered by mosquito bite were more infectious to outbred cd-1 mice than were sporozoites delivered by intravenous inoculation. the route of challenge also affected vaccine efficacy. in view of these findings and the fact that mosquito bites are the natural mode of sporozoite delivery, infectious mosquito bites should be considered the challenge protocol of choice for sporozoite vaccine efficacy trials. | 1999 | 10417207 |
| breeding structure of the sand fly lutzomyia longipalpis (lutz & neiva) in brazil. | eleven populations of lutzomyia longipalpis (lutz & neiva), the sand fly vector of leishmania chagasi, from different areas of brazil were analyzed for genetic variation at 16 enzyme loci. in this region, the prevalence of visceral leishmaniasis (vl) caused by l. chagasi is spotty and reproductive isolation among populations of lu. longipalpis has been reported. it is thought that morphologically similar cryptic species with varying vectorial capacity may be responsible for the discontinuous dis ... | 1999 | 10432072 |
| the status of the lutzomyia longipalpis species complex and possible implications for leishmania transmission. | 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 ... | 1999 | 10585647 |
| toward an understanding of the biochemical and pharmacological complexity of the saliva of a hematophagous sand fly lutzomyia longipalpis. | the saliva of blood-sucking arthropods contains powerful pharmacologically active substances and may be a vaccine target against some vector-borne diseases. subtractive cloning combined with biochemical approaches was used to discover activities in the salivary glands of the hematophagous fly lutzomyia longipalpis. sequences of nine full-length cdna clones were obtained, five of which are possibly associated with blood-meal acquisition, each having cdna similarity to: (i) the bed bug cimex lectu ... | 1999 | 10611354 |
| establishment and characterization of a new continuous cell line from lutzomyia longipalpis (diptera: psychodidae) and its susceptibility to infections with arboviruses and leishmania chagasi. | embryonic tissue explants of the sand fly lutzomyia longipalpis (lutz & neiva 1912) the main vector of leishmania chagasi (cunha and chagas), were used to obtain a continuous cell line (lulo). the tissues were seeded in mm/vp12 medium and these were incubated at 28 masculinec. the first subculture was obtained 45 days after explanting and 96 passages have been made to date. lulo is composed of epithelioid cells, showed a 0.04 generations/hour exponential growth rate and population doubling time ... | 2000 | 10656714 |
| maxadilan interacts with receptors for pituitary adenylyl cyclase activating peptide in human sh-sy5y and sk-n-mc neuroblastoma cells. | receptors for pituitary adenylyl cyclase activating peptide (pacap) have been identified in human sh-sy5y neuroblastoma cells with pacap being 1000-fold more potent than vasoactive intestinal peptide (vip) in [(125)i]pacap binding inhibition and stimulation of camp accumulation. maxadilan, a vasodilator peptide from the salivary gland of the sand fly lutzomyia longipalpis also specifically bound to sh-sy5y cells, and was equipotent to pacap in [(125)i]pacap and [(125)i]maxadilan binding inhibiti ... | 1999 | 10657479 |
| epidemiologic aspects of american visceral leishmaniasis in an endemic focus in eastern venezuela. | an endemic focus of american visceral leishmaniasis (avl) in eastern venezuela has been evaluated in terms of patients (n = 48), immunologic reactivity to leishmania in household contacts (n = 187) and neighborhood controls (n = 170), detection of leishmania (l. donovani complex) in dogs and wild animals by the polymerase chain reaction (pcr) and characteristics of the sandfly population. the male:female ratio of patients was 1.18:1; 89.6% were < or =12 years old. serologic reactivity was signif ... | 1999 | 10674675 |
| occurrence of sibling species of lutzomyia longipalpis (diptera: psychodidae) in venezuela: first evidence from reproductively isolated sympatric populations. | the delimitation of cryptic species within the main vector of the american visceral leishmaniasis, lutzomyia longipalpis, remains a topic of controversy. an analysis of genetic variability based on 8 enzymatic loci revealed fixed differences in 2 diagnostic loci, adenylate kinase (ak) and hexokinase (hk), between sympatric and allopatric populations at 4 localities in venezuela. the absence of heterozygotes for these 2 loci within 1 locality indicates, for the first time, the presence of 2 sympa ... | 1999 | 10674686 |
| salivary amylase activity of the phlebotomine sand fly, lutzomyia longipalpis. | both male and female adult stages of the sand fly lutzomyia longipalpis have detectable amylase activity in their salivary glands, as indicated by formation of p-nitrophenyl-alpha-d-maltoside from p-nitrophenyl-alpha-d-octoside and by hydrolysis of 4-nitrophenyl-alpha-d-maltoheptaoside-4,6,-o-ethylidene. no salivary alpha-glucosidase was detected. amylase activity was also found in the crop and midgut of female flies, although in a smaller amount. salivary amylase is significantly reduced from t ... | 2000 | 10727893 |
| [sandflies (diptera, psychodidae) in a secondary forest area in the paco do lumiar city, maranhao, brazil: a leishmaniasis transmission area]. | this paper analyzes the wealth of species, relative abundance, seasonal fluctuation, and nocturnal activity of sandflies. the field survey was conducted in a "capoeira" (secondary forest) area in the county of paço do lumiar, maranhão, where cutaneous and transmission of visceral leishmaniasis frequently occurs. sandflies were captured by cdc-type light traps from 6:00 pm to 6:00 am, once a month, from march 1997 to february 1998. a total of 489 specimens were collected (251 males and 238 female ... | 2000 | 10738174 |
| studies on populations of lutzomyia longipalpis (lutz & neiva, 1912) (diptera: psychodidae: phlebotominae) in brazil. | studies were performed on five brazilian populations of lutzomyia longipalpis: salvaterra (pa), são josé do ribamar (ma), canindé (ce), natal (rn) and gruta da lapinha, lagoa santa (mg). no morphological differences were observed that could distinguish between these populations. homogeneity tests showed that the allopatric populations display a certain heterogeneity and that the sympatric populations, with different patterns of spots, are homogeneous. the student-newman-keuls test, represented b ... | 2000 | 10800188 |
| 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 |
| delayed-type hypersensitivity to phlebotomus papatasi sand fly bite: an adaptive response induced by the fly? | the saliva of bloodsucking arthropods contains a large array of pharmacologically active compounds that assist hematophagy. arthropod saliva is also responsible for causing uncomfortable allergic responses in its vertebrate hosts. in this article, we investigate whether the sand fly phlebotomus papatasi, known to produce a strong delayed-type hypersensitivity (dth) in humans, could benefit from, and possibly adaptively induce, this response in their vertebrate hosts. in this study, we show that ... | 2000 | 10841567 |
| sibling species in the llutzomyia longipalpis complex differ in levels of mrna expression for the salivary peptide, maxadilan. | maxadilan is a small ( approximately 7 kda) protein found in the saliva of sand fly species in the lutzomyia longipalpis complex, vectors of the parasite causing visceral leishmaniasis, leishmania chagasi. it is a potent vasodilator and also has immunomodulatory affects. maxadilan recovered from different sibling species of the lu. longipalpis complex differ in amino acid content by as much as 23%, however all variants possess equivalent vasodilatory activity. therefore, the dramatic differences ... | 2000 | 10886415 |
| molecular and biologic characterization of leishmania parasites implicated in an epidemic outbreak in northwestern argentina. | leishmania (viannia) braziliensis and its variants were implicated in the epidemic outbreak of mucocutaneous leishmaniasis that occurred in salta, northwestern argentina, in 1985. a total of 24 suspected, untreated cases were evaluated clinically and parasitologically. four of five stable isolates were consistent with the reference strain of l. (v.) braziliensis as determined by monoclonal antibodies and indirect immunofluorescence or radioimmunobinding assays. zymodeme analysis in agarose gels ... | 2000 | 10894479 |
| 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 |
| correlated morphologic and genetic diversity among lutzomyia longipalpis (diptera: psychodidae) collections in venezuela. | diversity among lutzomyia longipalpis populations in venezuela was characterized using 2 methods: larval mouthpart morphology-morphometry and isoenzyme electrophoresis. analysis of the results suggested the presence of 2 morpho-genotypes. the mentum, maxillary comb, mandibular ventral teeth, and adenylate kinase and hexokinase enzyme-encoding loci suggested that a population from the northwestern coriano system (curarigua) is a distinct lineage within the l. longipalpis complex. three widely sep ... | 2000 | 10901644 |
| competence of the human host as a reservoir for leishmania chagasi. | the failure of control programs for visceral leishmaniasis (vl) that depend on elimination of infected dogs suggests that other reservoir hosts may participate in the transmission cycle. to determine whether persons infected with leishmania chagasi can infect the vector sand fly, laboratory-reared lutzomyia longipalpis were allowed to feed on brazilian subjects with active, cured, and asymptomatic vl and on asymptomatic residents of houses of persons with active vl. of 3747 insects that had fed, ... | 2000 | 10950806 |
| [prevalence of microbiota in the digestive tract of wild females of lutzomyia longipalpis lutz & neiva, 1912) (diptera: psychodidae)]. | we dissected the digestive tract of 245 females in pools of 35 flies forming 7 groups. these flies were lutzomyia longipalpis originating from lapinha cave, lagoa santa, minas gerais. out of the 8 species of bacteria isolated there was a predominancy of gram negative bacterias (gnb) in the group of non-fermenters of sugar belonging to the following species: acinetobacter lwoffii, stenotrophomonas maltophilia, pseudomonas putida and flavimonas orizihabitans. the group of gnb fermenters were: ente ... | 2000 | 10967602 |
| 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 |
| simulium vittatum (diptera: simuliidae) and lutzomyia longipalpis (diptera: psychodidae) salivary gland hyaluronidase activity. | hyaluronidase activity in the salivary gland homogenates of simulium vittatum (zetterstedt) is described, and its optimal ph determined. salivary activity was reduced significantly after a blood meal, indicating that it was secreted after blood feeding. phlebotomus papatasi (scopoli) also exhibited salivary hyaluronidase activity. these results indicate that hematophagous pool-feeding insects may secrete this enzyme to help the spread of salivary antihemostatic agents in the vicinity of the feed ... | 2000 | 11004788 |
| 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 |
| salivary proteins and glycoproteins in phlebotomine sandflies of various species, sex and age. | salivary gland proteins were studied in sandflies (diptera: psychodidae: phlebotominae) by electrophoretic techniques. in phlebotomus duboscqi neveu-lemaire the protein concentration was about 30 times higher in females than in males. sds page revealed eight major bands of 29-62 kda in salivary gland extracts (sge) from females, whereas only one band of 57kda was detected in males. the number of protein components in sge gradually increased with the age of females. in p. papatasi (scopoli) the t ... | 2000 | 11016431 |
| expression of heterologous promoters in lutzomyia longipalpis and phlebotomus papatasi (diptera: psychodidae) cell lines. | to establish a transient expression system for genes introduced into sand fly cell lines, we tested the expression of the luciferase reporter gene under control of different promoters. towards this end, we lipofected cell lines obtained from new and old world sand flies, ll-5 from lutzomyia longipalpis lutz & neiva and pp-9 from phlebotomus papatasi scopoli, respectively. the relative levels of luciferase expression were studied under control of drosophila melanogaster meigen heat shock protein ... | 2000 | 11126533 |
| [first record of finding lutzomyia longipalpis (lutz & neiva, 1912) in the urban area of brazil]. | this is a report of the first finding of visceral leishmaniasis' vector lutzomyia longipalpis in the urban area of campo grande, state of mato grosso do sul. the importance of this finding regarding the transmission of the disease in this area is discussed. | 2000 | 11175612 |
| density of sand flies (diptera: psychodidae) in domestic and wild animal shelters in an area of visceral leishmaniasis in the state of rio grande do norte, brazil. | the objective of the present study was to determine the association of sand flies with the presence of domestic and wild animals in the peridomiciliary area. the sand flies were collected using direct aspiration and cdc light traps placed in animal shelters. the results suggest that different sand flies species have different behavioral characteristics in an apparent preference for animal baits and that lutzomyia longipalpis and lu. evandroi were the most eclectic species regarding their biotope ... | 1999 | 10445997 |
| 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 |
| [sandflies (diptera, psychodidae) from an endemic leishmaniasis area in the cerrado region of the state of maranhão, brazil]. | this article presents a list of ten sandfly species from the genus lutzomyia frança, 1924 found in the counties of aldeias altas, capinzal do norte, caxias, codó, coelho neto, timbiras, timon and tuntum in northeastern maranhão, brazil. presence of sandflies was associated with cases of visceral and cutaneous leishmaniasis. some 377 specimens were captured indoors with cdc light traps and 1491 specimens in the peridomicile. the species were: lutzomyia cortelezii, lutzomyia evandroi, lutzomyia go ... | 1999 | 10502159 |
| 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 |
| [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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| [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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |