epidemiology of cutaneous leishmaniasis in colombia: environmental and behavioral risk factors for infection, clinical manifestations, and pathogenicity.through a longitudinal, active surveillance for leishmania (viannia) braziliensis and leishmania (viannia) panamensis infection and lesions on the pacific coast of colombia, risk factors for infection (leishmanin skin test conversion), leishmanial lesions, and pathogenicity were examined. risk factor information was obtained prior to and independently of case ascertainment. similar factors were associated with acquisition of infection and of leishmaniasis, including male sex, age > 10 years, and ...19938354913
human monocyte infection by leishmania (viannia) panamensis. role of complement receptors and correlation of susceptibility in vitro with clinical phenotype.peripheral blood monocytes (pbms) from healthy individuals who had experienced distinctive clinical outcomes after natural infection with leishmania (viannia) were evaluated in vitro with respect to susceptibility to infection by stationary phase promastigotes of l. (v). panamensis. concomitantly, the role of complement receptors (cr) cr1 and cr3 in the attachment and entry of l. (v). panamensis into human monocytes was analyzed using mabs to cr1 (cd35) and cr3 (cd11b) to inhibit competitively t ...19948301130
leishmania (viannia) panamensis-induced cutaneous leishmaniasis in balb/c mice: pathology.leishmania (viannia) panamensis infected balb/c mice developed a progressive swelling in the injected footpad that grew to a tumour-like lesion from day 80 onwards. we did not observe any typical ulcera, necrosis or metastasis to other parts of the skin. neither did we observe any histopathological changes in liver or spleen during the experiment. at the site of injection, we observed progressive changes ranging from a moderate, mixed inflammatory infiltrate with few leishmania amastigotes in th ...19938217783
development of colombian isolates of leishmania (viannia) panamensis, le. (v.) guyanensis and le. (v.) braziliensis in the sandfly lutzomyia intermedia (lutz & neiva, 1912) under experimental conditions.the development of colombian leishmania species of the subgenus viannia in lutzomyia intermedia was similar to that observed with brazilian le. (v.) braziliensis: colonization of the pylorus by paramastigotes; promastigotes in the midgut and massive infection of stomodeal valve. difference was observed in the number of paramastigotes colonizing the pylorus, which was smaller in colombian leishmania species than brazilian le. braziliensis.19938139462
[leishmaniasis in ecuador. 6. epidemiological and entomological note on the focus of leishmaniasis in zumba].the zumba focus of tegumentary leishmaniasis lies in the southwards amazonian region of ecuador. a clinico-epidemiological study has been carried out in the area on 83 patients attending health centers. all the biotopes suitable for sandflies, including dwellings, have been sampled from february to september 1992 by light trap and human bait catches. the number of sandflies caught amounts to 2,547. anthropophilic sandfly fauna is poor and only three species have been recorded. lutzomyia serrana ...19948024349
[leishmaniasis in ecuador. 5. leishmaniasis and anthropization on the pacific coast].we have evaluated the impact of anthropization of the forest on the incidence of leishmaniasis, due to leishmania panamensis, in three coastal study areas, corriente grande (primary forest), paraiso escondido and la tablada (secondary forest). the situation of isolated dwellings, in deforested areas, has also been analysed in the last two stations. in each station, the study of the density of anthropophilic sand flies, specially lutzomyia trapidoi, has been conducted in the domestic environment, ...19948024348
[leishmaniasis in ecuador. 4. natural infestation of the dog by leishmania panamensis].in two endemic leishmaniasis foci of the pacific coast of ecuador 34 dogs suspected of having the disease have been surveyed clinically, serologically and parasitologically; immunofluorescence and electrosyneresis tests, lymph node aspirates, biopsies and smears have been performed. from two dogs with ulcers only one had ulcers on the muzzle and the scrotum infected by leishmania (l. guyanensis complex). the isolated strain was identified as leishmania panamensis. the disease was strictly cutane ...19948024347
[leishmaniasis in ecuador. 3. lutzomyia trapidoi, vector of leishmania panamensis].lutzomyia trapidoi, the more abundant anthropophilic species, is a presumed leishmaniasis vector in the pacific foothills of ecuador. three biotopes have been sampled (dwelling, and nearby coffee crop and primary forest) in the focus of paraiso escondido, by human bait catches, from august 1991 to october 1992. a large number of sandflies, 6,965 specimens, have been dissected to estimate peri and hypopyloric infections. all the peripyloric infections, characterized by isoenzyme electrophoresis, ...19948024346
[leishmaniasis in ecuador. 1. incidence of cutaneous leishmaniasis on the pacific coast].a clinico-epidemiologic survey on cutaneous leishmaniasis, due to leishmania panamensis, was carried out on 961 persons in two study areas of the pacific coast of ecuador, to estimate the prevalence and the incidence of the disease. in the preandean hills, at paraiso escondido, the prevalence of active lesions was 4.8%; in the hills of the coastal cordillera, at la tablada, it was 3.6%. the incidence of new cases in 1991 was high: 147% in the first village, and 106% in the second. these data are ...19948024344
a putative leishmania panamensis/leishmania braziliensis hybrid is a causative agent of human cutaneous leishmaniasis in part of a survey of human leishmaniasis in nicaragua we examined phenotypic and genotypic characteristics of 40 leishmania isolates. we identified 3 distinct parasites associated with cutaneous disease in this area; leishmania panamensis (40% of cases), leishmania braziliensis (33%), and a strain which exhibits the heterozygous isoenzyme and dna fingerprinting patterns expected of a l. panamensis/l. braziliensis hybrid (27%). there was complete correlation between the isoenzyme and dna data f ...19947800411
phlebotomine sandflies associated with a focus of cutaneous leishmaniasis in valle del cauca, colombia.a survey was made of the phlebotomine sandfly fauna of la guaira, a village with coffee plantations near cali, colombia, from which cases of american cutaneous leishmaniasis had been reported due to leishmania (viannia) panamensis and le. (v.) braziliensis. among six species of sandfly collected on human bait, lutzomyia youngi was most important in terms of biting nuisance. lu.columbiana, lu.lichyi and lu.scorzai as well as lu.youngi adults occurred throughout the year. sandfly man-biting activi ...19957548944
identification, using isoenzyme electrophoresis and monoclonal antibodies, of leishmania isolated from humans and wild animals of ecuador.six strains of leishmania isolated from wild mammals and humans on the pacific coast of ecuador were identified by isoenzyme electrophoresis and by their reactivity patterns to a cross-panel of specific monoclonal antibodies using a radioimmune binding assay. single isolates from sciurus vulgaris, potos flavus, and tamandua tetradactyla were identified as leishmania amazonensis. three other strains, isolated from cutaneous lesions of humans, were identified as leishmania panamensis.19892919726
ultrastructural biology of leishmania (viannia) panamensis (=leishmania braziliensis panamensis) in lutzomyia gomezi (diptera: psychodidae): a natural host-parasite association.the development of leishmania (viannia) panamensis in a natural sand fly host, lutzomyia gomezi, was studied by light and transmission electron microscopy. new aspects of peripylarian parasite behavior and morphology in the sand fly gut, early bloodmeal stages, and ultrastructural development in the anterior gut were documented. eight distinct morphological forms were observed in the life cycle of the parasite within the insect. in the bloodmeal, amastigotes (1) transformed into stumpy promastig ...19892916730
extracellular cultivation and morphological characterization of amastigote-like forms of leishmania panamensis and l. braziliensis.two strains of the leishmania braziliensis complex have been adapted to grow extracellularly at elevated temperature as amastigote-like forms in a cell-free medium. these parasites can be serially cultivated and maintained at 32 degrees c for l. panamensis (wr442; l. braziliensis panamensis) and at 28 degrees c for l. braziliensis (m5052; l. braziliensis braziliensis). several observations are presented that the forms adapted at elevated temperature are amastigote-like. morphologically, the amas ...19892810145
leishmania braziliensis in the squirrel monkey: development of primary and satellite lesions and lack of cross-immunity with leishmania donovani.three female and 2 male adult laboratory-reared squirrel monkeys (saimiri sciureus) that previously had been inoculated with leishmania (leishmania) donovani and had recovered from experimental visceral leishmaniasis were each inoculated intradermally at the dorsal base of the tail with 2.2 x 10(7) culture-derived promastigotes of leishmania (viannia) panamensis. the progression and regression of subsequent lesions were examined for 36 wk in all 5 monkeys after which 3 of the monkeys were killed ...19902380874
distribution and etiology of leishmaniasis in colombia.a total of 340 leishmania strains, isolated from humans, animals, and sand flies from various regions of colombia, were examined by isozyme electrophoresis. seven different leishmania species were identified. leishmania panamensis and l. braziliensis were the most common, representing 53.8% and 30.3% of the total, respectively. isolation rates of the other species were as follows: l. chagasi, 9.4%; l. guyanensis, 2.6%; l. amazonensis, 1.8%; l. mexicana, 0.8%; and a new species requiring addition ...19902316790
development of leishmania (viannia) panamensis lesions and relationship of numbers of amastigotes to lesion area on antimony-treated and untreated hamsters.young adult (60-70-g) male golden hamsters (mesocricetus auratus) each were injected intradermally at the dorsal base of the tail with 15 x 10(6) promastigotes of leishmania (viannia) panamensis (mhom/pa/83/wr539), and progression and regression of subsequent lesions were evaluated for up to 17 wk postinfection (pi) as to area, weight, and number of amastigotes within lesions in untreated hamsters and in hamsters treated with meglumine antimoniate (glucantime). in untreated hamsters total area o ...19911919929
metastatic capability of leishmania (viannia) panamensis and leishmania (viannia) guyanensis in golden hamsters.the pattern and kinetics of internal dissemination and frequency of cutaneous metastatic lesions resulting from experimental infection of golden hamsters with leishmania (viannia) panamensis and leishmania (viannia) guyanensis were examined. nineteen strains were evaluated: 16 l. (v.) panamensis isolated from patients and 3 l. (v.) guyanensis, 2 isolated from human cases and 1 who reference strain originating from a sandfly vector. lymphatic dissemination occurred within 3 mo and was observed fo ...19911919926
diffuse cutaneous leishmaniasis with mucosal involvement in colombia, caused by an enzymatic variant of leishmania panamensis. 19948036672
antileishmanial activity of sodium stibogluconate fractions.sodium stibogluconate, a pentavalent antimony derivative produced by the reaction of stibonic and gluconic acids, is the drug of choice for the treatment of leishmaniasis. it has been reported to be a complex mixture rather than a single compound. we separated sodium stibogluconate into 12 fractions by anion-exchange chromatography. one fraction accounted for virtually all the leishmanicidal activity of the fractionated material against leishmania panamensis promastigotes, with a 50% inhibitory ...19938239593
loss of the gp46/m-2 surface membrane glycoprotein gene family in the leishmania braziliensis complex.immunization with the gp46/m-2 membrane glycoprotein of leishmania amazonensis has been shown to induce a protective immune response against infection. we have surveyed a variety of trypanosomatid species and genera for the presence and expression of this gene family, information that will be relevant to future vaccine studies against leishmaniasis. molecular karyotype analysis revealed the presence of gp46/m-2 genes in all members of the leishmania mexicana complex, leishmania major, leishmania ...19921542309
refractory barriers in the sand fly phlebotomus papatasi (diptera: psychodidae) to infection with leishmania panamensis.the life cycle of leishmania panamensis in phlebotomus papatasi was studied to characterize barriers limiting parasite colonization, differentiation, migration, and attachment in an unnatural sand fly host. the insects were fed a suspension of l. panamensis-infected macrophages and human erythrocytes, and were examined up to 16 days post-infection by light and electron microscopy. histologic examination of 401 flies showed the peritrophic membrane to be the first important barrier to parasite es ...19921539756
herbicides to curb human parasitic infections: in vitro and in vivo effects of trifluralin on the trypanosomatid protozoans.leishmaniasis is a major tropical disease for which current chemotherapies, pentavalent antimonials, are inadequate and cause severe side effects. it has been reported that trifluralin, a microtubule-disrupting herbicide, is inhibitory to leishmania amazonensis. in this study, the in vitro effect of trifluralin on different species of trypanosomatid protozoans was determined. in addition to l. amazonensis, trifluralin is effective against leishmania major and leishmania tropica, which cause cuta ...19938516314
insulin-like growth factor i is a growth-promoting factor for leishmania promastigotes and amastigotes.leishmaniases are diseases caused by protozoa of the genus leishmania that affect more than 20 million people in the world. the initial phase of the infection is fundamental for either the progression or control of the disease. the leishmania parasites are injected in the skin as promastigotes and then, after been phagocytized by the host macrophages, rapidly transform into amastigotes. in this phase different nonspecific cellular and humoral elements participate. we have shown previously that i ...19989789067
molecular karyotype characterization of leishmania panamensis, leishmania mexicana, and leishmania major-like parasites: agents of cutaneous leishmaniasis in ecuador.molecular karyotypes of leishmania isolates from patients with cutaneous leishmaniasis in ecuador were analyzed by pulsed-field gel electrophoresis (pfge) and southern blot hybridization. the dna karyotypes of l. major-like parasites were similar between two human isolates from a lowland coastal and a highland andean region, but were apparently different from those of eleven world health organization reference strains including l. major. the smallest chromosome of 240 kilobases in l. major-like ...19938517490
molecular karyotype and chromosomal localization of genes encoding two major surface glycoproteins, gp63 and gp46/m2, hsp70, and beta-tubulin in cloned strains of several leishmania species.the molecular karyotypes of several leishmania isolates (leishmania amazonensis, leishmania braziliensis, leishmania guyanensis, leishmania panamensis, leishmania donovani, leishmania major, leishmania aethiopica, leishmania tropica, leishmania enriettii) have been analyzed by clamped homogeneous electric field (chef) gel electrophoresis. the chromosomal localization of genes encoding 2 major surface glycoproteins, gp63 and gp46/m2, heat shock protein 70 (hsp70), and beta-tubulin was determined ...19911779988
leishmania differentiation in natural and unnatural sand fly hosts.leishmania differentiation in the gut of phlebotomine sand flies was evaluated based on five light and electron microscopic studies of natural (leishmania panamensis/lutzomyia gomezi, leishmania chagasi/lutzomyia longipalpis) and unnatural (leishmania mexicana/lutzomyia abonnenci, leishmania panamensis/phlebotomus papatasi, leishmania major/lutzomyia longipalpis) life cycles. in the bloodmeal, transformation of amastigotes into stumpy promastigotes occurred before or during division. further div ...19938461893
mapping of the linear antigenic determinants of the leishmania infantum hsp70 recognized by leishmaniasis sera.mapping of antigenic determinants of the leishmania infantum hsp70 was studied by analysis of the reactivity of sera from dogs with natural visceral leishmaniasis against a collection of peptides representing overlapping sequences of the hsp70. despite the considerable variation in the immune response among individuals three immunodominant regions were revealed encompassing residues 241 to 260 (region i), 435 to 469 (region ii) and from amino acid 601 to the carboxyl-terminal end of the protein ...19968905399
immunocytochemical and histopathologic characterization of lesions from patients with localized cutaneous leishmaniasis caused by leishmania panamensis.localized cutaneous leishmaniasis (lcl) in colombia is caused primarily by leishmania panamensis, a different species from those reported in brazil, french guiana, and venezuela. because different parasites may elicit disparate immune responses, the present study was undertaken to establish the leukocyte participation in the immune response against l. panamensis. epidermal and dermal immune complexes were studied using an avidinbiotin immunoperoxidase technique and specific monoclonal antibodies ...19968916790
cytolytic activity in the genus leishmania: involvement of a putative pore-forming protein.we describe here that parasites of the genus leishmania contain a cytolytic activity which acts optimally at ph 5.0 to 5.5 and at 37 degrees c in vitro. or the four species examined, leishmania (leishmania) amazonensis and leishmania (leishmania) major presented considerable hemolytic activity, whereas leishmania (viannia) panamensis and leishmania (viannia) guyanensis showed little and no hemolytic activity, respectively. the cytolytic factor of l. amazonensis promastigotes was characterized as ...19968926057
antimonial treatment of hamsters infected with leishmania (viannia) panamensis: assessment of parasitological cure with different therapeutic schedules.the objective of the study was to establish the effective dose and route of administration of glucantime for treating hamsters infected with leishmania (viannia) panamensis and to use this method to test new treatment regimens to attain clinical and parasitological cure. in the first experiments animals were inoculated subcutaneously in the hind foot with 5 x 10(6) promastigotes of l. panamensis (hom/col/84/1099) from a 6 d culture. one month after inoculation, glucantime was administered intram ...19938266413
experimental infection of balb/c mice with leishmania panamensis and leishmania mexicana: induction of early ifn-gamma but not il-4 is associated with the development of cutaneous lesions.resistance to the leishmaniae is associated with interferon (ifn)-gamma mediated activation of macrophages. in this study, balb/c mice were infected with three leishmania strains that cause progressively growing cutaneous lesions without obvious dissemination: l. mexicana mexicana giving rise to rapidly growing lesions, and l. (viannia) panamensis and l. mexicana-like, which both cause slowly developing lesions. the rate of lesion growth was compared to induction of early local and systemic ifn- ...19979246206
the inflammatory response promotes cutaneous metastasis in hamsters infected with leishmania (viannia) panamensis.the influence of nonspecific and immunologically elicited inflammatory responses on the development of metastatic lesions was examined in the hamster model of leishmania (viannia) panamensis infection. delayed type hypersensitivity (dth) responses were induced using the contact sensitizing agent dnfb (2, 4-dinitro-1-fluorobenzene) and infection with l. panamensis followed by intradermal application of leishmanin. nonspecific inflammatory response was achieved by the surgical excision of toes. th ...19968636852
immunoblot analysis of leishmania panamensis antigens in sera of patients with american cutaneous leishmaniasis.sera from 86 colombian patients with parasitologically confirmed cutaneous leishmaniasis were studied by immunoblot analysis in order to identify a specific pattern for leishmania infection. a soluble extract of leishmania panamensis was used as the antigen. sera from patients with chagas' disease and sera from patients with no record of infection with trypanosomatids were also studied. the sera from patients with cutaneous leishmaniasis specifically recognized fractions of 120 kda (76.7%), 123 ...19979399491
evidence for hybridization by multilocus enzyme electrophoresis and random amplified polymorphic dna between leishmania braziliensis and leishmania panamensis/guyanensis in ecuador.the taxonomic attribution of four leishmania stocks isolated from humans in ecuador has been explored by both multilocus enzyme electrophoresis and random amplified polymorphic dna. for three loci, mlee results showed patterns suggesting a heterozygous state for a diploid organism, while the corresponding homozygous states are characteristic of the leishmania panamensis/guyanensis complex and leishmania braziliensis, respectively. other enzyme loci showed characters attributable to either the l. ...19979304809
rapid identification of leishmania species from formalin-fixed biopsy samples by polymorphism-specific polymerase chain reaction.the precise identification and classification of leishmania species is important for public health surveillance since different species cause different clinical features of the disease. a highly specific polymerase chain reaction (pcr) panel was developed to enable the identification of the five major leishmania species that cause new world cutaneous leishmaniases. the primers used for this panel were designed to distinguish the polymorphism in sequences of commonly amplified dna bands of the pa ...19989573358
mucosal leishmaniasis due to leishmania (viannia) panamensis in colombia: clinical characteristics.the leishmaniases are a group of diseases whose clinical presentation is in part determined by the infecting species. until recently, mucosal leishmaniasis was attributed exclusively to leishmania (viannia) braziliensis; however, the capacity of other species of the subgenus viannia to invade mucosal tissue has been documented. this report examines the clinical characteristics of 23 parasitologically diagnosed patients with mucosal leishmaniasis due to l. (v.) panamensis from the pacific coast o ...19989684627
sensitivity of leishmania viannia panamensis to pentavalent antimony is correlated with the formation of cleavable dna-protein complexes.the emergence of leishmania less sensitive to pentavalent antimonial agents (sbvs), the report of inhibition of purified topoisomerase i of leishmania donovani by sodium stibogluconate (pentostam), and the uncertain mechanism of action of antimonial drugs prompted an evaluation of sbvs in the stabilization of cleavable complexes in promastigotes of leishmania (viannia). the effect of camptothecin, an inhibitor of topoisomerase, and additive-free meglumine antimoniate (glucantime) on the stabiliz ...19989687395
the site of cutaneous infection influences the immunological response and clinical outcome of hamsters infected with leishmania panamensis.we determined that the site of inoculation (foot or snout) influences the clinical evolution and immune responses of hamsters infected with leishmania (viannia) panamensis. hamsters infected in the snout showed (i) a more rapid and severe lesion evolution at multiple time points (p < 0.05), (ii) a more extensive inflammatory infiltrate and tissue necrosis, (iii) a higher tissue parasite burden, (iv) a higher antibody titre (p < 0.01), but lower antigen-specific spleen cell proliferative response ...200312911522
extracellular amastigote-like forms of leishmania panamensis and l. braziliensis. ii. stage- and species-specific monoclonal antibodies.immunochemical evidence, employing monoclonal antibodies, shows that the forms of l. braziliensis complex axenically grown at elevated temperature are amastigote-like. the monoclonal antibodies were raised against membrane proteins of amastigote-like forms, strains of both l. panamensis (wr442) and l. braziliensis (m5052), which were grown axenically. the specificities of these antibodies were examined by indirect radioimmune binding assay, indirect immunofluorescent assay and western blot analy ...19892478699
in situ characterization of the human host response to leishmania panamensis.both host and parasite determinants influence the outcome of leishmania infections. human host responses in cutaneous leishmaniasis of limited duration caused by a single species of the viannia (v) subgenus were studied in skin biopsies obtained from lesions caused by leishmania (v) panamensis in 31 male patients from the colombian pacific coast. dermal infiltrates and histopathologic changes were characterized using monoclonal antibodies and an indirect immunoperoxidase method. dermal distribut ...19979415615
molecular and antigenic characterization of the leishmania (viannia) panamensis kinetoplastid membrane protein-11.the kinetoplastid membrane protein 11 (kmp-11) has been recently described in leishmania (leishmania) donovani as a major component of the promastigote membrane. two oligonucleotide primers were synthesized to pcr-amplify the entire encoding region of new world leishmania species. the leishmania (viannia) panamensis amplification product was clone, sequenced and the putative amino acid sequence determined. a remarkably high degree of sequence homology was observed with the corresponding molecule ...19989698903
the glycoinositolphospholipids from leishmania panamensis contain unusual glycan and lipid moieties.the cell surface of leishmania parasites is coated by glycosylphosphatidylinositol (gpi)-anchored macromolecules (glycoproteins and a lipophosphoglycan) and a polymorphic family of free gpi glycolipids or glycoinositolphospholipids (gipls). here we show that gipls with unusual glycan and lipid moieties are likely to be major cell surface components of l. panamensis (subgenus viannia) promastigotes. these glycolipids were purified by high performance thin layer chromatography and their structures ...19989735288
permissiveness of human monocytes and monocyte-derived macrophages to infection by promastigotes of leishmania (viannia) panamensis.during natural infections, leishmania is in contact with a variety of mononuclear phagocytic cells in different tissues, including resident macrophages and monocytes mobilized to the site of infection from the bone marrow and blood circulation. because the functional capabilities of fully differentiated macrophages and blood monocytes differ, the outcome of infection by leishmania may depend upon the stage of differentiation of the host cells. to address this question, we evaluated leishmania pa ...19989920322
leishmania (viannia) panamensis-induced cutaneous leishmaniasis in susceptible and resistant mouse strains.we studied the susceptibility to leishmania (viannia) panamensis in strains of mice. the c57bl/6 strain was resistant and showed self-controlled lesion at the injected foot pad. the balb/c and dba/2j strains were susceptible and showed a foot swelling that started day 20 post-infection and progressed to a tumour-like lesion in later period of observation. the cba/hj strain was found to be of intermediary resistance. in contrast to other known cutaneous leishmaniasis in mice, the lesion in l. (v. ...19958731258
inefficacy of allopurinol as monotherapy for colombian cutaneous leishmaniasis. a randomized, controlled trial.hundreds of thousands of cases of cutaneous leishmaniasis occur each year worldwide. available therapies are parenteral, moderately toxic, and costly.19979027276
reinfection in american cutaneous leishmaniasis: evaluation of clinical outcomes in the hamster model.there is no clear understanding of the outcome of reinfection in new world cutaneous leishmaniasis, and its role in the relationship to the development of protection or secondary disease. for this reason, reinfection experiments with homologous (leishmania panamensis-l. panamensis) and heterologous (l. major-l. panamensis) species of leishmaniae were conducted in the hamster model. the different protocols for primary infections prior to the challenge with l. panamensis were as follows: (a) l. ma ...19989698870
genetic analysis of leishmania parasites in ecuador: are leishmania (viannia) panamensis and leishmania (v.) guyanensis distinct taxa?in the course of an epidemiologic survey in ecuador, the following collection of leishmania stocks was isolated: 28 from patients with clinical signs of leishmaniasis, 2 from sloths, 1 from a dog, and 4 from sand flies. for genetic characterization of these stocks, multilocus enzyme electrophoresis (mlee) and random amplified polymorphic dna (rapd) were used. twenty six of the 35 stocks were identified as either leishmania (v.) panamensis or l. (v.) guyanensis, 2 stocks were identified as l. (v. ...199910586922
distinct innate and acquired immune responses to leishmania in putative susceptible and resistant human populations endemically exposed to l. (viannia) panamensis infection.mechanisms of constitutive and acquired susceptibility/resistance to leishmania viannia panamensis (l. (v ) p.) were investigated in endemically exposed human populations presenting either recurrent disease (putative susceptible) or subclinical infection (clinically resistant). cutaneous delayed type hypersensitivity response to leishmanin was significantly lower among individuals experiencing recurrent leishmaniasis than among those whose skin test converted without developing the disease. mono ...200010792848
intraspecific heterogeneity in the mini-exon gene localization of leishmania (viannia) panamensis and leishmania (viannia) guyanensis from colombia.intraspecific heterogeneity was demonstrated in the mini-exon gene localization from leishmania (viannia) panamensis and l. (viannia) guyanensis. different karyotypes were detected in human isolates circulating in endemic areas of colombia. the presence of mini-exon gene sequences on chromosomes of different sizes, ranging from 370 to 800 kb in l. (v.) panamensis and from 500 to 800 kb in l. (v.) guyanensis, was observed and was neither strain nor species specific. in some cases, hybridization w ...200011191900
cultivation and characterization of stable leishmania guyanensis complex axenic amastigotes derived from infected u937 cells.the study of the differential regulation of several genes, in both leishmania parasite life cycle forms, has been simplified by the development of in vitro axenic amastigote culture. different reports have described extracellular amastigote production and maintenance from several leishmania spp. a general approach to induce amastigote-like transformation includes progressive ph and temperature changes. production of axenic amastigotes in continuous cultures using amastigotes recovered from macro ...200011357988
identification of a differentially expressed mrna in axenic leishmania panamensis amastigotes.differential display technique was applied in order to identify transcripts which are present in axenic amastigotes but not in promastigotes of the leishmania panamensis parasites. one of them was cloned and the sequence reveals an open reading frame of 364 amino acids (approximately 40 kda). the deduced protein is homologous to the serine/threonine protein kinases and specially to the mitogen activates protein kinases from eukaryotic species. southern blot analysis suggest that this transcript, ...200111562712
inhibition of macrophage invasion by monoclonal antibodies specific to leishmania (viannia) braziliensis promastigotes and characterisation of their antigens.monoclonal antibodies that specifically recognise leishmania (viannia) braziliensis promastigotes were produced and termed sst-2, sst-3 and sst-4. sst-2 recognises a conformational epitope present in a 24-28 kda doublet and in a 72 kda component, as verified by western blotting. indirect immunofluorescence showed that the antigen recognised by sst-2 is distributed homogeneously on the parasite surface. sst-3 recognises a flagellar glycoprotein of approximately 180 kda. the reactivity of this mab ...200111595232
usefulness of sampling with cotton swab for pcr-diagnosis of cutaneous leishmaniasis in the new this study, we tested the polymerase chain reaction (pcr)-method to diagnose cutaneous leishmaniasis (cl) by taking exudate materials from lesions with cotton swabs, using our previously tested (pcr) panel comprised of leishmania (viannia) panamensis, l. (v.) braziliensis, l. (v.) guyanensis, l. (leishmania) mexicana and l. (l.) amazonensis. the objectives of the present study were to improve the sampling method convenient for the patients and to test the usefulness of samples taken with cott ...200211835896
leishmaniasis: recognition and management with a focus on the immunocompromised patient.leishmaniasis is a protozoan disease whose clinical manifestations depend both on the infecting species of leishmania and the immune response of the host. transmission of the disease occurs by the bite of a sandfly infected with leishmania parasites. infection may be restricted to the skin in cutaneous leishmaniasis (cl), to the mucous membranes in mucosal leishmaniasis or spread internally in visceral leishmaniasis (vl). in the last 2 decades, leishmaniasis, especially vl, has been recognized a ...200211893221
treatment of cutaneous leishmaniasis with a topical antileishmanial drug (wr279396): phase 2 pilot study.we studied the efficacy of wr279396, a topical formulation of aminoglycosides that cures 100% of cutaneous leishmaniasis lesions in mice. we conducted what is to our knowledge the first controlled study of wr279396 therapy for clinical cutaneous leishmaniasis. a total of 45 colombian soldiers, all men, were randomly assigned to treatment with wr279396 (33 patients) or placebo (12 patients). each lesion was treated twice daily for 20 days. lesions were measured at the end of therapy and at 45, 90 ...200212135285
evaluation of pcr for diagnosis of american cutaneous leishmaniasis in an area of endemicity in northeastern brazil.pcr-based approaches targeting kinetoplast dna were evaluated for the diagnosis of american cutaneous leishmaniasis (acl) in regions of endemicity in northeastern brazil. a total of 119 cutaneous biopsy specimens from patients with acl and nonleishmaniasis cutaneous lesions were studied. two pcr-based systems were used; one was specific for the subgenus viannia, and the other was specific for the genus leishmania. the pcr specific for the subgenus viannia had a sensitivity of 95.4%, whereas the ...200212354848
susceptibility of spiny rats (proechimys semispinosus) to leishmania (viannia) panamensis and leishmania (leishmania) chagasi.the role of proechimys semispinosus as reservoir of leishmania (viannia) panamensis on the colombian pacific coast was experimentally evaluated. the susceptibility to l. chagasi also was assessed to determine the utility of this rodent as a model for studying reservoir characteristics in the laboratory. wild-caught animals were screened for natural trypanosomatid infections, and negative individuals were inoculated intradermally (id) in the snout or feet with 10(7) promastigotes of l. panamensis ...200212386716
endemically exposed asymptomatic individuals show no increase in the specific leishmania (viannia) panamensis-th1 immune response in comparison to patients with localized cutaneous colombia, most cases of human cutaneous leishmaniasis are caused by leishmania (viannia) panamensis. interestingly, up to 30% of the exposed population do not suffer from clinical leishmaniasis although it is likely that they are continuously infected with leishmania parasites. since it is believed that the induction of efficient th1 immune responses protects against leishmania infections both in humans and in animal models, we determined if endemically exposed asymptomatics showed stronger l ...200212654087
antiprotozoal 6-substituted-5,6-dihydro-alpha-pyrones from raimondia cf. monoica.dichloromethane extracts of both the roots and the leaves of raimondia cf. monoica showed in vitro antiplasmodial and leishmanicidal activities against plasmodium falciparum and leishmania panamensis, respectively. three 6-substituted 5,6-dihydro-2h-pyran-2-ones were isolated. (1) and (2) were identified as (6s)-(5'-oxohepten-1'e,3'e-dienyl)-5,6-dihydro-2h-pyran-2-one (1) and (6r)-(5'-oxohepten-1'z,3'e-dienyl)-5,6-dihydro-2h-pyran-2-one (2), respectively. (-)-arentilactone (3) was also isolated. ...200312822907
mapping the proteome of leishmania viannia parasites using two-dimensional polyacrylamide gel electrophoresis and associated this study we have demonstrated the potential of two-dimensional electrophoresis (2de)-based technologies as tools for characterization of the leishmania proteome (the expressed protein complement of the genome). standardized neutral range (ph 5-7) proteome maps of leishmania (viannia) guyanensis and leishmania (viannia) panamensis promastigotes were reproducibly generated by 2de of soluble parasite extracts, which were prepared using lysis buffer containing urea and nonidet p-40 detergent. t ...200312872554
leishmania (viannia) panamensis-specific ige and iga antibodies in relation to expression of human tegumentary leishmaniasis.leishmania (viannia) panamensis-specific ige and iga antibodies were quantified in patients with parasitologically confirmed american tegumentary leishmaniasis using a radioallergosorbent test (rast) and an enzyme-linked immunosorbent assay (elisa), respectively. the rast values, presented as the mean +/- sem percentage of total isotope added, were significantly elevated in patients having disease evolution greater than 12 months (3.14 +/- 0.91), as compared with those with an evolution time of ...19938357080
characterizing cellular immune response to kinetoplastid membrane protein-11 (kmp-11) during leishmania (viannia) panamensis infection using dendritic cells (dcs) as antigen presenting cells (apcs).in vitro peptide binding assays and dcs pulsed with recombinant kmp-11 (rkmp-11) plus six 20-mer overlapping peptides covering the entire protein of leishmania (viannia) panamensis (l(v)p) promastigotes were used to identify t-cell epitopes in this protein. such in vitro binding assays, using hla drb1* 0101, -0401, -0701 and -1101 alleles, demonstrated that two peptide sequences (deefnkkmqeqnakffadkp and fkhkfaelleqqkaaqypsk) exhibited high hla drb1* 0401 allele binding capacity. rkmp-11 specifi ...200312940963
minicircle variable region probes for characterization of leishmania (viannia) species.the minicircle molecules present in the kinetoplast dna (kdna) network constitute a particularly useful molecular tool because they are a multicopy target and present a variable region that differs among minicircle classes in the same network. using the polymerase chain reaction (pcr) and a set of primers directed outwardly from the minicircle conserved region, it is possible to prepare molecular probes representing the pool of variable regions from the different minicircle classes in the kdna. ...199910386456
antileishmanial and immunomodulatory activity of xylopia discreta.this study aimed at determining the in vitro antileishmanial activity of the essential oil and eight extracts obtained from xylopia discreta. j774 and u937 macrophages were exposed to the different substances to establish the median lethal concentration (lc(50)). the median effective concentration (ec(50)) was obtained by determining the reduction of leishmania panamensis-infected cells. a selectivity index (si) (lc(50)/ec(50)) >or= 20 defined a specific activity for one xylopia discreta leaf ex ...200919751474
leishmania (viannia) panamensis: cloning of the histone h1 genes by representational difference analysis.we report the use of representational difference analysis to identify genes that have up-regulated expression in the amastigote life-cycle stage of leishmania (viannia) panamensis. this simultaneous process of selection and amplification allowed the cloning of several specific dna fragments. one of them shows a high percentage of similarity with histone h1 genes from other trypanosomatids and, as expected, is up-regulated in the amastigote life-cycle stage. the gene is present in two copies that ...200616289088
leishmaniasis recidiva cutis due to leishmania (viannia) panamensis in subtropical ecuador: isoenzymatic characterization.information regarding leishmaniasis recidiva cutis (lrc), a clinical variant of cutaneous leishmaniasis, in the new world is scarce. lrc is characterized by slowly progressing lesion(s) that appear after a variable period of time, from months to years, in or around the scar of an apparently clinically healed sore.200616445499
coumarins from galipea panamensis and their activity against leishmania panamensis.two new coumarin compounds (1 and 2), phebalosin (3), its derived artifact murralongin (4), and murrangatin acetonide (5) were isolated from the leaves of galipea panamensis. the structures of 1 and 2 were assigned as 7-{[(2r*)-3,3-dimethyloxiran-2-yl]methoxy}-8-[(2r*,3r*)-3-isopropenyloxiran-2-yl]-2h-chromen-2-one and 7-methoxy-8-(4-methyl-3-furyl)-2h-chromen-2-one, respectively, on the basis of their spectroscopic data (primarily nmr and ms). compounds 1-3 were tested against axenic amastigote ...201020423106
successful topical treatment of murine cutaneous leishmaniasis with a combination of paromomycin (aminosidine) and gentamicin.cutaneous leishmaniasis is presently treated with 20 days of parenteral therapy with a frequently toxic drug (antimony). topical formulations of paromomycin (15%) plus methylbenzethonium chloride (mbcl, 12%) or plus urea (10%) in soft white paraffin have been tested for old and new world disease in humans. we compared the efficacy of a new topical formulation, wr 279,396 (paromomycin [15%] plus gentamicin [0.5%]) to the clinical formulations in the treatment of cutaneous disease in balb/c mice. ...199910219319
leishmania (viannia) panamensis/leishmania (leishmania) amazonensis--a warning. 199910234193
atypical clinical variants in new world cutaneous leishmaniasis: disseminated, erysipeloid, and recidiva cutis due to leishmania (v.) recent times, there has been an increase in the number of reports for new and rare variants of cutaneous leishmaniasis (cl). here, we describe three unusual clinical forms of cl identified in ecuadorian children. a total of 131 patients with cl were diagnosed over a 2-year period of active search. in 3 (2.29%), the lesions were very unusual; these included erysipeloid, recidiva cutis (lrc), and disseminated leishmaniasis (dl). the erysipeloid case is characterized by erythematous and indurate ...200516103590
treatment of new world cutaneous leishmaniasis with miltefosine.miltefosine (2.5 mg/kg/day for 28 days) was investigated for treatment of new world cutaneous leishmaniasis in colombia and guatemala. the data from a controlled study was remarkably similar to the data of a prior uncontrolled pilot study. in the controlled study, the per-protocol 6-month cure rate for leishmania panamensis disease was 91% compared with a concomitant placebo cure rate of 38%. in guatemala, the cure rate for l. braziliensis and l. mexicana disease was approximately 50% compared w ...200616930649
bite the hand that sprays you.a 56-year-old man presented with a cutaneous lesion on his right hand (figure 1). approximately 6 weeks previously, he had traveled to costa rica for missionary work. during his travel he used a diethyltoluamide-containing insect repellant, but spent one night in the jungle without a mosquito net. four weeks after his return, he noted a 3 x 2.5-cm ulcer with raised edges and surrounding erythema on the dorsum of his right hand. the patient recalled applying insect repellant with his right hand t ...200617085999
leishmania panamensis: a 44bp deletion in gp63 gene is found in cdna and genomic libraries. 199910464408
[efficacy and toxicity of pentavalent antimonials (glucantime and pentostam) in an american cutaneous leishmaniasis animal model: luminometry application].the pentavalent antimonial compounds glucantime and pentostam are the first line drugs used in anti-leishmania treatment. however, no in vivo studies have compared the efficacy and toxicity of these drugs where host variability has been controlled. biochemical studies of leishmania have detected differences between the two drugs with regard to dna topoisomerase i inhibition, a phenomenon that possibly impacts treatment efficacy. to evaluate the clinical efficacy, hamsters were infected intraderm ...200415678803
leishmanicidal activity of pycnoporus the search for antiparasite compounds from the colombian flora, an active compound against leishmania (viannia) panamensis amastigotes was isolated from the fungi pycnoporus sanguineus. the structural elucid-ation was achieved with spectroscopic methods ((1)h and (13)c nmr and ms). this compound was identified as ergosterol 5,8-endoperoxide.200616619346
leishmanicidal activity of passifloricin a and derivatives.several natural and hemisyntetic passifloricins were assayed against leishmania panamensis amastigotes. high leishmanicidal activity as well as toxicity was observed. the structure of a new compound is also reported.200418007468
[presence of infected vectors of leishmania (v.) panamensis within dwellings in two endemic foci in the foothill of the middle magdalena valley, western boyacá, colombia].case records of leishmaniasis of the years 1997 to 2003 of the department of boyaca showed that since the year 2000 the department experienced an unusual rise in the incidence of cutaneous leishmaniasis that might correspond to an epidemic outbreak in the western region of the department. age and gender distribution of cases supported a domestic transmission.200617361845
nodular lymphangitis: a distinctive clinical entity with finite etiologies.nodular lymphangitis, characterized by inflammatory nodules along the lymphatics draining a primary skin infection, most commonly follows superficial inoculation with sporothrix schenckii, nocardia brasiliensis, mycobacterium marinum, leishmania (viannia) panamensis/guyanensis, and francisella tularensis. epidemiologic context, clinical presentation, and presumed incubation period help to predict the specific etiologic microorganism. sporotrichosis, often occurring in gardeners, remains the most ...200818687205
antimony resistance and trypanothione in experimentally selected and clinical strains of leishmania panamensis.the participation of trypanothione in clinical and experimental antimony (sb) resistance in leishmania panamensis was examined by using specific inhibitors. buthionine sulfoximine (bso) significantly reversed the resistance to trivalent sb (sb(iii)) of promastigotes of experimentally derived sb-resistant lines, supporting the participation of a trypanothione-mediated mechanism of resistance. in contrast, promastigotes of strains isolated at the time of clinical treatment failure and resistant to ...200818824610
leishmania panamensis transmission in the domestic environment: the results of a prospective epidemiological survey in santander, colombia.domestic transmission now appears to be the principal route of leishmania panamensis infection in deforested regions characterized by the replacement of primary forest by permanent plantations, i,e coffee or cacao crops. this paper presents the results of the disease patterns in a representative population of the opón focus, in santander, colombia.200617361849
[morphology and cytochemistry of aedes aegypti's cell cultures (diptera: culicidae) and susceptibility to leishmania panamensis (kinetoplastida: trypanosomatidae)].morphology and cytochemistry of aedes aegypti's cell cultures (diptera: culicidae) and susceptibility to leishmania panamensis (kinetoplastida: trypanosomatidae). the first cellular line of aedes aegypti was developed by grace in 1966; afterwards, other cellular lines of this species have been generated. these have been used for the study of pathogenic organisms like viruses, bacteria and parasites, which demonstrates their importance in biomedical applications. this research describes, for the ...200819256419
pregnancy enhances the innate immune response in experimental cutaneous leishmaniasis through hormone-modulated nitric oxide production.the maintenance of host defense during pregnancy may depend on heightened innate immunity. we evaluated the immune response of pregnant hamsters during early infection with leishmania (viannia) panamensis, a cause of american cutaneous leishmaniasis. at 7 days post-infection, pregnant animals showed a lower parasite burden compared with nonpregnant controls at the cutaneous infection site (p=0.0098) and draining lymph node (p=0.02). resident peritoneal macrophages and neutrophils from pregnant a ...200818347075
leishmania (viannia) panamensis: an in vitro assay using the expression of gfp for screening of antileishmanial drug.promastigotes of leishmania (viannia) panamensis were successfully transfected with p6.5-egfp to express green fluorescent protein. the transfectants remained infective to macrophages, providing an in vitro model for screening antileishmanial drugs. this was demonstrated by flow cytometry of macrophage-associated gfp after exposure of infected cultures to known antileishmanial drugs, i.e. amphotericin b and glucantime. fluorescence of gfp diminished progressively from infected cells with increas ...200919303871
leishmanicidal activity of aliphatic and aromatic lactones: correlation structure-activity.several aliphatic and aromatic lactones and two dimers were synthesized using the sequence: allylation - esterification - metathesis. these compounds were active in vitro against intracellular amastigotes of leishmania panamensis. the structure-activity relationship showed the importance of the aliphatic side chain to enhance the biological activity and to obtain lower cytotoxicity. it was also observed that a decrease in the size of the lactone ring increases the selectivity index.200919633618
in vitro studies on the relationship between the anti-inflammatory activity of physalis peruviana extracts and the phagocytic process.the study of plants used in traditional medicine has drawn the attention of researchers as an alternative in the development of new therapeutics agents, such as the american solanaceae physalis peruviana, which has significant anti-inflammatory activity. the physalis peruviana anti-inflammatory effect of ethanol or ether calyces extracts on the phagocytic process was assessed by using an in vitro phagocytosis model (leishmania panamensis infection to murine macrophages). the physalis peruviana e ...201019678736
leishmania panamensis: comparative inhibition of nuclear dna topoisomerase ii enzymes from promastigotes and human macrophages reveals anti-parasite selectivity of fluoroquinolones, flavonoids and pentamidine.certain model inhibitors exerted selective action against the catalytic activity of nuclear dna topoisomerase ii (topii) of leishmania panamensis promastigotes. the second-generation fluoroquinolones enoxacin and ciprofloxacin exhibited extraordinarily high anti-parasite selectivity displaying 582- and 40-fold greater potencies against l. panamensis topii as compared with the human macrophage enzyme. the flavonoids quercetin and ellagic acid showed inverse specificities, the former being 161-fol ...200717466980
association of acenaphthoporphyrins with liposomes for the photodynamic treatment of leishmaniasis.acenaphthoporphyrins are potential photosensitizers for photodynamic therapy, but their hydrophobicity limits their potential. liposomes have been widely investigated as delivery vehicles that can transport hydrophobic drugs in biological systems. here we study the association of acenaphthoporphyrins with liposomes made up of dimyristoyl phosphatidylcholine (dmpc), and to liposomes made up of a mixture of dmpc, cholesterol (chol) and distearoyl phosphatidylglycerol (dspg) in a 2:1:0.8 molar rati ...201020202163
an enhanced method for the identification of leishmania spp. using real-time polymerase chain reaction and sequence analysis of the 7sl rna gene region.the accurate identification of leishmania spp. is important for the treatment of infected patients. molecular methods offer an alternative to time-consuming traditional laboratory techniques for species determination. we redesigned a 7sl rna gene-based polymerase chain reaction and sequence assay for increased species identification. dna extracted from 17 reference strains and 10 cultured clinical isolates was examined. sequence comparison was used successfully to identify organisms to the compl ...201020226334
detection of leishmania in unaffected mucosal tissues of patients with cutaneous leishmaniasis caused by leishmania (viannia) species.leishmania (viannia) species are the principal cause of mucosal leishmaniasis. the natural history and pathogenesis of mucosal disease are enigmatic. parasitological evaluation of mucosal tissues has been constrained by the invasiveness of conventional sampling methods.200919569974
differentiation of leishmania (viannia) panamensis and leishmania (v.) guyanensis using bcci for hsp70 pcr-rflp.leishmania panamensis and leishmania guyanensis are two species of the subgenus viannia that are genetically very similar. both parasites are usually associated with cutaneous leishmaniasis, but also have the potential to cause the mucocutaneous form of the disease. in addition, the study of foci and consequently the identification of vectors and probable reservoirs involved in transmission require a correct differentiation between both species, which is important at epidemiological level. we ex ...201020227738
[molecular and immunological analyses suggest the absence of hydrophilic surface proteins in leishmania (viannia) panamensis].the genus leishmania is divided into two subgenera: leishmania and viannia. the two subgenera present several important differences such as the pathology they cause in susceptible hosts, their in vitro growth behavior, their genetic characteristics, and the expression pattern of several proteins, including those of the hydrophilic surface protein family.200819034366
molecular identification of the parasites causing cutaneous leishmaniasis on the caribbean coast of colombia.all clinical manifestations of leishmaniasis exist in colombia, the cutaneous form being the most frequent in the department of sucre, where the leishmania species associated with cutaneous leishmaniasis (cl) is unknown. this study was carried out to determine which leishmania species was responsible for cl in sucre, based on amplification and sequencing of the cyt b gene. isolates of leishmania were obtained after cl diagnosis of eight patients who received attention in several health care cent ...201020084397
selective action of fluoroquinolones against intracellular amastigotes of leishmania (viannia) panamensis in vitro.we have demonstrated that fluoroquinolones, a class of antibacterial agents that act through inhibition of type ii dna topoisomerases, exert selective action against intracellular amastigotes of leishmania (viannia) panamensis at concentrations that are achievable in vivo. drug cytotoxicity assays employing the luciferase reporter gene revealed that intracellular amastigotes were 6.6- to 25.9-fold more sensitive than human macrophages (p < 0.05) to second-generation fluoroquinolones in vitro. th ...200516539034
synthesis of novel quinoline-based 4,5-dihydro-1h-pyrazoles as potential anticancer, antifungal, antibacterial and antiprotozoal agents.a new series of n-substituted 2-pyrazolines 9a-f, 10a-f, 11a-f, 12a-f and 13a-f were obtained from the cyclocondensation reaction of [(7-chloroquinolin-4-yl)amino]chalcones 8a-f with hydrazine hydrate and its derivatives. fourteen of the synthesized compounds including the starting chalcones were selected by us national cancer institute (nci) for testing their anticancer activity against 60 different human cancer cell lines, with the most important gi50 values ranging from 0.28 to 11.7 μm (0.13- ...201728329730
duplex real-time reverse transcriptase pcr to determine cytokine mrna expression in a hamster model of new world cutaneous leishmaniasis.the syrian hamster, mesocricetus auratus, has distinct immunological features and is uniquely susceptible to intracellular pathogens. studies in hamsters are limited by the relative unavailability of tools to conduct immunological studies. to address this limitation we developed duplex real-time reverse transcriptase (rt) pcr assays for the relative quantification of the mrnas of hamster cytokines, chemokines, and related immune response molecules.201020569429
in vitro and in vivo prophylactic and curative activity of the triterpene saponin px-6518 against cutaneous leishmania species.the oleanane triterpene saponin px-6518, with known potent in vitro and in vivo activity against leishmania donovani, was investigated for its spectrum against the cutaneous species leishmania mexicana, leishmania panamensis and leishmania major.201021131319
leishmanicidal activity of synthetic antimicrobial peptides in an infection model with human dendritic cells.different species of leishmania are responsible for cutaneous, mucocutaneous or visceral leishmaniasis infections in millions of people around the world [14]. the adverse reactions caused by antileishmanial drugs, emergence of resistance and lack of a vaccine have motivated the search for new therapeutic options to control this disease. different sources of antimicrobial molecules are under study as antileishmanial agents, including peptides with antimicrobial and/or immunomodulatory activity, w ...201121262294
leishmanicidal and cytotoxic activities of extracts and naturally-occurring compounds from two lauraceae species.the in vitro leishmanicidal effects of ethanolic extracts and fifteen naturally-occurring compounds (five lignans, eight neolignans, a diterpene and a dihydrochalcone), obtained from pleurothyrium cinereum and ocotea macrophylla, were evaluated on promastigotes of leishmania panamensis and l. braziliensis. in addition, in order to determine the selective action on leishmania species as a safety principle, in vitro cytotoxicity on j774 cells was also evaluated for test compounds and extracts. one ...201121425681
toll-like receptors participate in macrophage activation and intracellular control of leishmania (viannia) panamensis.toll-like receptors (tlrs) play a central role in macrophage activation and control of parasitic infections. their contribution to the outcome of leishmania infection is just beginning to be deciphered. we examined the interaction of leishmania panamensis with tlrs in the activation of host macrophages. l. panamensis infection resulted in up-regulation of tlr1, tlr2, tlr3 and tlr4 expression, and induced tnfα secretion by human primary macrophages at comparable levels and kinetics as specific tl ...201121518783
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