immunotherapy as a treatment of american cutaneous leishmaniasis: preliminary studies in brazil.a prophylactic vaccine composed of killed promastigotes of five stocks of leishmania was tested as an immunotherapeutic agent against american cutaneous leishmaniasis (acl). the agent was administered by deep intramuscular injection daily for 10 days, followed by a 10-day interval. out of 62 patients so treated, 47 (76%) were considered clinically cured; 41 required 2-10 treatment courses and the other six 11-19 courses. none of the patients treated by immunotherapy displayed adverse side-effect ...19921339971
glucantime resistant leishmania promastigotes are sensitive to pentostam.growth inhibition in vitro tests were used to study the susceptibility to pentostam of different leishmania strains involved in cutaneous and mucocutaneous leishmaniasis--one glucantime sensitive strain, three naturally glucantime resistant strains and one glucantime resistant line developed by in vitro drug exposure. contrasting with the high degree of glucantime resistance, all strains were sensitive to pentostam. these differences suggest that there is some relationship between chemical struc ...19921340539
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
transcribing and replicating particles in a double-stranded rna virus from leishmania.during the replicative cycle of many double-stranded rna viruses, transcription of particles with a double-stranded rna genome alternates with replication of particles containing a single-stranded genome. in virions infecting some strains of leishmania guyanensis the putative transcriptase and replicase activities of the rna-dependent rna polymerase were previously detected in vitro. northern hybridization to rna of known polarity demonstrates that the single-stranded rna products are of positiv ...19921620160
the protein sequence predicted from a leishmania guyanensis gp63 major surface glycoprotein gene is divergent as compared with other leishmania species. 19921625703
lrv1 viral particles in leishmania guyanensis contain double-stranded or single-stranded rna.the 32-nm-diameter spherical viral particles found in the cytoplasm of leishmania guyanensis cumc1-1a sediment at 130s and have a buoyant density of approximately 1.4 g/ml in cesium chloride gradients. these particles contain a 5.3-kb double-stranded rna, while single-stranded rna that corresponds to the viral positive strand is associated with less-dense particles. these results suggest a conservative and sequential mode of lrv1 viral rna replication that is exemplified by the scv l-a virus of ...19921738198
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
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
[cutaneous south-american leishmaniasis. parasitological and serological diagnosis by indirect immunofluorescence and enzyme linked immunoassay (elisa). 94 cases].a parasitological (direct test and culture) and serological (iif and elisa) survey was carried out in 94 soldiers infested by a cutaneous south american leishmaniasis during a training in the guyanese forest. 52 p.c of the parasitological tests were positive, direct test being much more sensitive than cultures. by this technique, leishmania viannia guyanensis was detected 8 times, and leishmania viannia braziliensis twice. i.i.f. was negative in all cases because the utilization of a non-homolog ...19912072848
isolation of leishmania guyanensis from lesions of the nasal mucosa. 19883271946
[current aspects of endemic mucocutaneous leishmaniasis in brazil].mucocutaneous leishmaniasis has a large incidence in brazil. biochemical, immunological and biological studies have characterized three disease agents: leishmania mexicana amazonensis, leishmania brasiliensis guyanensis and leishmania brasiliensis brasiliensis; these have distinct geographical distributions. the last one is the most common and is the most difficult to treat. destructive mucosal lesions can occur days, months or years after the cutaneous lesions. the montenegro intradermal test, ...19854066323
detection of trypanosoma cruzi and leishmania using the polymerase chain reaction. 19947476218
the dermal leishmaniases of brazil, with special reference to the eco-epidemiology of the disease in amazonia.six species of leishmania are at present known to cause cutaneous and/or mucocutaneous leishmaniasis in brazil, and they are all to be found in the amazon region of this country. the eco-epidemiology of each is discussed, with the observation that the amazonian leishmaniases are all zoonoses, with their source in silvatic mammals and phlebotomine sandfly vectors. with man's destruction of the natural forest in southern brazil, some sandfly species have survived by adapting to a peridomestic or d ...19947476229
glucantime susceptibility of leishmania promastigotes under variable growth conditions.growth inhibition of leishmania promastigotes by glucantime was compared in three different media. glucantime inhibited the growth of leishmania cultured in complex medium but did not affect parasite growth when added to cells cultured in defined or semi-defined media. supplementation of the complex medium with biopterin partially reversed the glucantime effect in sensitive strains, although the addition of folic acid or oleic acid did not alter the activity of glucantime. differences in fatty a ...19957624285
leishmania rna virus 1-mediated cap-independent translation.recently, a group of related leishmania rna viruses (leishmania rna virus 1 [lrv1]) has been isolated from leishmania guyanensis and l. brasiliensis. these viruses persist in the cytoplasm and contain double-stranded rna genomes. miniexon sequences are absent from the 5' end of the viral rna, and the 5' end of the viral rna lacks a cap structure, suggesting that lrv1 has evolved a cap-independent mechanism of translation. cap-independent translation of picornavirus genomic rna requires a cis ele ...19957651407
genotypic polymorphisms in experimental metastatic dermal leishmaniasis.molecular karyotype and kdna restriction analyses were utilized to examine the genetic heterogeneity and plasticity of the leishmania (viannia) guyanensis strain whi/br/78/m5313, composed of metastatic and non-metastatic populations. cloning revealed that the strain was constituted by multiple closely related populations that were distinguishable by restriction fragment polymorphisms in kdna. size polymorphisms in molecular karyotype were not detected. passage of clones in hamsters and recovery ...19957770084
[the therapy of cutaneous and mucocutaneous leishmaniasis]. 19948076505
relationships between cell surface protease and acid phosphatase activities of leishmania promastigote.a correlation between the ratio of the cell surface protease activity to phosphatase activity and the complexity of the pattern of cell surface exposed polypeptides of leishmania promastigotes was demonstrated for various strains grown under similar conditions. the ratio of the cell surface protease activity to acid phosphatase activity was high for l. major and l.b. panamensis and it correlates with the expression of a single polypeptide of 63 kda on their cell surface. intermediate and lower r ...19938114687
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
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
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
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
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
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
[identification of leishmania (v) guyanensis during recurrences of cutaneous leishmaniasis contracted in french guyana]. 19969026604
an oligonucleotide probe derived from kdna minirepeats is specific for leishmania (viannia).sequence analysis of leishmania (viannia) kdna minicircles and analysis of multiple sequence alignments of the conserved region (minirepeats) of five distinct minicircles from l. (v.) braziliensis species with corresponding sequences derived from other dermotropic leishmanias indicated the presence of a sub-genus specific sequence. an oligonucleotide bearing this sequence was designed and used as a molecular probe, being able to recognize solely the sub-genus viannia species in hybridization exp ...19969040846
stained smears as a source of dna. 19969137743
[cutaneous leishmaniasis and leishmania species in french guiana]. 19969139207
carbohydrate and lpg expression in leishmania viannia subgenus.glycosylated molecules expressed on the cell surface of leishmania promastigotes contribute to the outcome of contact between the parasite and its invertebrate and vertebrate hosts. the expression of several such molecules is growth phase dependent. information on the expression of carbohydrates by leishmania of the viannia subgenus (braziliensis complex), a widespread cause of morbidity in the americas, is fragmentary. we have examined the relationship between growth phase and the expression of ...19979267410
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
specific in vitro cleavage of a leishmania virus capsid-rna-dependent rna polymerase polyprotein by a host cysteine-like protease.antibodies raised against baculovirus-expressed rna-dependent rna polymerase (rdrp) recognized a 95-kda antigen and two smaller proteins in sucrose-purified leishmania virus particles isolated from infected parasites. the 95-kda antigen is similar in size to one predicted by translation of the rdrp open reading frame (orf) alone. in an effort to reconcile in vitro observations of translational frameshifting on leishmania rna virus 1-4 transcripts, we have developed an in vitro cleavage assay sys ...19979371554
hygromycin b resistance mediates elimination of leishmania virus from persistently infected parasites.a series of px63-hyg derivatives encoding leishmania rna virus 1-4 (lrv1-4) sequences were electroporated into cells of leishmania strain m4147, a virus-infected strain of l. guyanensis. after 6 weeks of drug selection (hygromycin b), transfected parasites lacked detectable quantities of viral genomic double-stranded rna, viral capsid protein, and rna-dependent rna polymerase (rdrp) activity. evidence of viral infection was not recovered upon removal of the drug. while viral rna transcripts were ...19979371555
cutaneous leishmaniasis in venezuela caused by infection with a new hybrid between leishmania (viannia) braziliensis and l. (v.) guyanensis. 19979566221
generation of the short rna transcript in leishmaniavirus correlates with the growth of its parasite host, leishmania.leishmaniavirus 1 is a double-stranded rna virus that infects the new world kinetoplastid parasites, leishmania braziliensis, and leishmania guyanensis. the isolated virus particles contain an rna-dependent rna polymerase which exhibits both transcriptase activity for genome-length plus-strand synthesis and replicase activity for genome-length minus-strand synthesis. recently, we identified a 320 nucleotide short rna transcript of leishmaniavirus 1-4, derived from the 5' end of the viral plus-st ...19989571632
american cutaneous leishmaniasis due to leishmania (viannia) guyanensis as an initial clinical presentation of human immunodeficiency virus infection.the authors present the first report of leishmania (viannia) guyanensis (l.(v.) guyanenesis) associated with human immunodeficiency virus (hiv) in a brazilian heterosexual man. it is also the first case of hiv infection associated with american cutaneous leishmaniasis in brazilian western amazonia. the patient had cutaneous and mucous lesions with a negative montenegro skin test. histopathology showed large numbers of amastigotes, even in a lesion which had clinically healed. l.(v.) guyanenesis ...19989643323
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
response to heterologous leishmanins in cutaneous leishmaniasis in nigeria--discovery of a new focus.a pilot study was undertaken to preliminary illustrate the leishmanin skin test (lst) positivity to distinct antigen preparations (derived from promastigote of either leishmania major or l. amazonensis, or pooled l. mexicana, l. amazonensis and l. guyanensis) in cutaneous leishmaniasis (cl) patients and healthy subjects living in two endemic foci in nigeria. the study was designed to provide insights into whether cross-species leishmanin, such as that prepared from new world leishmania could be ...19989698838
zymodeme and serodeme characterization of leishmania isolates obtained from costa rican patients.thirty-four leishmania isolates obtained from costa rican patients, from different geographical areas, were characterized by isoenzyme electrophoresis and indirect immunofluorescense with monoclonal antibodies. thirty-two were characterized as l. panamensis strains and two were l. braziliensis variants. we confirm the evident predominance of l. panamensis as the main etiological agent of leishmaniasis in costa rica and the existence of l. braziliensis in the country.19989698858
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
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
effect of glucantime on field and patient isolates of new world leishmania: use of growth parameters of promastigotes to assess antimony susceptibility.the effect of pentavalent meglumine antimoniate (glucantime) on the growth kinetics of promastigotes of 13 south american leishmania strains isolated from patients, sylvatic reservoirs, and vectors was studied. four of five l. (viannia) braziliensis human isolates were obtained from drug-responsive patients and one was isolated from an unresponsive mucocutaneous-type infection. studies involved the cell yield at the late log phase, the growth rate, and the growth-curve patterns of promastigotes ...19989766900
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
short report epidemiologic studies on cutaneous leishmaniasis in eastern panama.the panamanian ministry of health, through the interamerican development bank, contracted the gorgas memorial laboratory to conduct epidemiologic studies on leishmaniasis and malaria in eastern panama from july 1984 through june 1985. preliminary results of the biomedical and entomologic teams investigating the epidemiology of cutaneous leishmaniasis in the eastern part of the country are presented in this short report. the principal findings of the study revealed 1) a large disparity in the inc ...19999988322
leishmania (viannia) panamensis/leishmania (leishmania) amazonensis--a warning. 199910234193
energy-dependent efflux from leishmania promastigotes of substrates of the mammalian multidrug resistance pumps.we demonstrated the existence of three transport activities in promastigotes of leishmania braziliensis, leishmania guyanensis, and leishmania mexicana. the first activity, an energy-dependent efflux of pirarubicin, was observed in all leishmania species and inhibited by verapamil, by 2-[4-(diphenylmethyl)-1-piperazinyl]ethyl-5-(trans-4,6-dimethyl-1, 3,2-dioxaphosphorinan-2-yl)-2,6-dimethyl-4-(3-nitrophenyl)-3-py ridinecarboxylate p oxide (pak104p) and by the phenothiazine derivatives: thioridaz ...199910376995
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
leishmania: fine mapping of the leishmanolysin molecule's conserved core domains involved in binding and internalization.the leishmanolysin molecule's role in the uptake of leishmania parasites by the human u937 pro-myelocytic cell line was studied, using synthetic peptides representing the complete leishmania (viannia) guyanensis leishmanolysin protein amino acid sequence. the particular peptides present in two protein's core domains efficiently impaired the internalization of promastigotes from four different leishmania species and modified the kinetics of the binding of heterologous recombinant leishmanolysin p ...199910464034
leishmania panamensis: a 44bp deletion in gp63 gene is found in cdna and genomic libraries. 199910464408
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
a novel leishmania infantum recombinant antigen which elicits interleukin 10 production by peripheral blood mononuclear cells of patients with visceral leishmaniasis.we report here the characterization of a novel leishmania infantum protein termed paple22 (22-kda potentially aggravating protein of leishmania). a positive clone from a cdna library was identified by serum of a visceral leishmaniasis (vl) patient. full-length cdna obtained using rapid amplification of cdna ends-pcr codes for a 22-kda protein. in l. infantum promastigotes an endogenous nuclear protein of 14-kda electrophoretic mobility was found by using an antiserum prepared against the fusion ...200010639426
comparison of pcr results using scrape/exudate, syringe-sucked fluid and biopsy samples for diagnosis of cutaneous leishmaniasis in ecuador. 199910717745
delayed culture of leishmania in skin biopsies.between january 1997 and october 1998, 16 skin biopsies collected from 13 patients with cutaneous leishmaniasis in french guiana were inoculated in culture medium after travel for 3-17 days from the place of biopsy to the culture laboratory in france. each biopsy fragment was introduced near the flame of a bunsen burner into the transport medium (rpmi medium supplemented with 10% fetal calf serum) which was maintained at ambient temperature during postal delivery to france. in france the biopsie ...199910717763
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
phylogenetic analysis of the 5' subterminal region of isolates of leishmania rna virus-1.leishmania rna virus-1 (lrv1) is a double-stranded rna virus present in some leishmania species. the virus genome consists of a 450-nucleotide, 5' untranslated region (utr) followed by the coat gene and the rna-dependent rna polymerase (rdrp). it has been shown that the 5' end utr of the genome promotes internal initiation of translation in an in-vitro assay, indicating the presence of an internal ribosomal entry site (ires) element upstream of the coat gene. the nucleotide sequences of the 5' s ...200010827867
leishmania (viannia) guyanensis: a new minicircle class exclusive to this specie isolated from a dna cosmid library useful for taxonomic purposes.a new minicircle class exclusive to this specie isolated from a dna cosmid library useful for taxonomic purposes. experimental parasitology 94, 143-149. in this paper we describe a new minicircle class exclusive to leishmania (viannia) guyanensis. the minicircle class was obtained with the aid of a total dna cosmid library. the library was screened with an ecori fragment isolated from l. (v.) guyanensis (m4147). after screening seven clones were selected which showed strong hybridisation. clones ...200010831378
cutaneous leishmaniasis following local trauma: a clinical pearl.cutaneous leishmaniasis is acquired from the bite of an infected sand fly and can result in chronic skin lesions that develop within weeks to months after a bite. local trauma has been implicated as a precipitating event in the development of skin lesions in patients who have been infected with leishmania species. here we report a case series and review the literature on patients who developed cutaneous leishmaniasis after local trauma, which may familiarize clinicians with this presentation.200010913426
clonal diversity in the expression and stability of the metastatic capability of leishmania guyanensis in the golden hamster.metastatic disease is a major concern of dermal leishmaniasis caused by leishmania of the viannia subgenus. the golden hamster provides an experimental model of systemic dissemination and cutaneous metastasis of leishmania viannia. we have exploited this model to examine the expression of parasite virulence in cloned populations derived from a strain of l. guyanensis previously shown to be highly metastatic in the hamster. metastatic capacity manifested as dissemination throughout the lymphoid o ...200010958458
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
interleukin (il)-13 is the predominant th2 cytokine in localized cutaneous leishmaniasis lesions and renders specific cd4+ t cells unresponsive to il-12.semiquantitative reverse transcription-polymerase chain reaction analysis of leishmania lesion cytokine profile showed a th2 cytokine expression pattern, as reflected by interleukin (il)-4 and il-13 mrna expression. there was a predominance of il-13 in most lesions from patients with american localized cutaneous leishmaniasis caused by leishmania guyanensis. il-13 production by peripheral blood mononuclear cells in response to specific leishmania antigens was confirmed in these patients. the abs ...200111237813
comparison of cutaneous leishmaniasis due to leishmania (viannia) braziliensis and l. (v.) guyanensis in brazil: clinical findings and diagnostic approach.we compared the clinical findings and diagnostic methods for 66 patients with cutaneous leishmaniasis in the state of bahia, brazil, who were infected by leishmania (viannia) braziliensis (group a), with those for 68 patients in the state of amazonas, brazil, who were mainly infected by leishmania (viannia) guyanensis (group b). differences were observed with regard to number, size, and location of skin lesions and to the pattern of lymphatic involvement. patients in group b had smaller and more ...200111303265
first report of lutzomyia (nyssomyia) umbratilis ward & frahia, 1977 outside of amazonian region, in recife, state of pernambuco, brazil (diptera: psychodidae: phlebotominae).lutzomyia umbratilis, a known vector of leishmania guyanensis in the north of amazon basin, has been exclusively found in the amazonian region. here we report for the first time the occurrence of this species in northeastern brazil. the epidemiological importance of the occurrence of this species in the atlantic forest is commented.200111313636
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
sensitivity of the polymerase chain reaction for the diagnosis of cutaneous leishmaniasis due to leishmania (viannia) guyanensis.the sensitivity of the polymerase chain reaction (pcr) in 35 consecutive outpatients with cutaneous leishmaniasis caused by leishmania (viannia) guyanensis was evaluated using, as gold standard, the in vitro isolation of the parasite through culture of aspirates of the cutaneous ulcers. all isolates were identified using electrophoretic enzyme analysis. patients were mainly young males with recent onset disease without prior specific treatment. pcr was performed using dna extracted from fresh fr ...200111412806
flow cytometry, a useful tool for detecting the lethal effect of pentamidine on leishmania viannia complex promastigote forms.flow cytometry (fc), combined with propidium iodide as supravital colorant, was used to study leishmania(subgenus viannia)panamensis [l (v) panamensis] complex strain susceptibility to meglumine antimoniate, sodium stibogluconate and pentamidine. despite all drugs examined being leishmanicidal to axenic forms in in vitro trials (in the presence of macrophages), axenic amastigotes directly exposed to these drugs were highly resistant under our experimental conditions. a direct lethal effect on pr ...200111592861
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
comparison of cutaneous leishmaniasis due to leishmania (viannia) braziliensis and l. (v.) guyanensis in brazil: therapeutic response to meglumine antimoniate.we conducted a quasi-experimental study to compare the response to meglumine antimoniate in patients with localized cutaneous leishmaniasis from two endemic areas of brazil that were infected by two leishmania species. sixty-one were infected by leishmania (viannia) braziliensis (group b) and 57 by l. (v.) guyanensis (group g). all had a parasitologically proven diagnosis and were treated with 20 mg of pentavalent antimonial (sbv)/kg/day given intravenously or intramuscularly for 20 days. main o ...200111716098
cell surface carbohydrates and in vivo infectivity of glucantime-sensitive and resistant leishmania (viannia) guyjanensis cell lines.the cell surface plays an important role in the interaction of parasites with their hosts. drug resistance in the protozoan leishmania may involve changes in cell-surface composition, although it is not known whether infectivity is also affected. one sensitive and two glucantime-resistant lines of leishmania (viannia) guyanensis previously isolated were inoculated into hamsters. the sensitive line caused the disease to manifest earlier than the resistant lines. imprinting analyses of infected ma ...200111728019
high intralesional interleukin-10 messenger rna expression in localized cutaneous leishmaniasis is associated with unresponsiveness to treatment.the intralesional expression of cytokines (interleukin [il]-4, il-13, il-10, and interferon-gamma) was analyzed in 65 patients with localized cutaneous leishmaniasis due to leishmania guyanensis before specific treatment with pentamidine isethionate. the local expression of il-10 was significantly higher in patients who responded poorly to treatment than in patients whose lesions were regressing. when an il-10 level >10 (ratio of the concentration of il-10 [pg/microl] to that of beta-actin [pg/m ...200111740743
attempt to differentiate leishmania (leishmania) amazonensis, l. (l.) chagasi, leishmania (viannia) braziliensis and l. (v.) guyanensis using the ssr-pcr technique.the ability to differentiate reference strains of leishmania (leishmania) amazonensis, l. (l.) chagasi, leishmania (viannia) braziliensis and l. (v.) guyanensis was evaluated using the simple sequence repeat polymerase chain reaction (ssr-pcr) technique. this technique differentiates the leishmania species, generating distinct dna amplicon profiles. the ssr-pcr profiles were similar to but more reproducible than those produced by rapd. ssr-pcr is presented as an alternative to other molecular me ...200111763439
identification of antigenically distinct populations of leishmania (viannia) guyanensis from manaus, brazil, using monoclonal antibodies.eighty leishmania isolates from patients who contracted cutaneous leishmaniasis in the manaus region, amazonas state, brazil, were identified as leishmania (viannia) guyanensis by the electrophoretic profiles of six enzymes. none reacted with the species-specific monoclonal antibody b19. two l. (v.) guyanensis subpopulations were detected with the monoclonals b2 and b12. the lack of b19 expression by the l. (v.) guyanensis strains in the present study contrasts with that of the vast majority of ...200211904100
[vertical stratification of phlebotomine sandfly fauna (diptera, psychodidae) in a primary non-flooded forest of the central amazon, amazonas state, brazil].studies on the vertical stratification of phlebotomine sandfly fauna were conducted in a non-flooded primary forest at a tropical forest experimental station of the national institute of amazonian research from october 1998 to march 1999. cdc light traps were placed at one, 10, and 20 meters above ground. a total of 2,859 sandflies were captured, belonging to the lutzomyia (99.93%) and brumtomyia (0.07%) genera, represented by 38 species. in the lutzomyia gender, the most frequent sub-gender was ...200212048608
analysis of minicircle classes in leishmania (viannia) species.this paper reports the analysis of minicircle sequence classes from 4 leishmania species, all belonging to the 'new world' species of the subgenus viannia: leishmania braziliensis, l. guyanensis, l. panamensis and l. peruviana. a minicircle library was constructed for each species, and clones were analysed by restriction enzyme digest and sequence analysis. 319 minicircles from the 4 species were examined and 96 of these were wholly or partially sequenced. the sequences of 41 whole minicircles-- ...200212055852
the rarity of infection with leishmania (viannia) braziliensis among patients from the manaus region of amazonas state, brazil, who have cutaneous leishmaniasis.the frequency of leishmania ( viannia) braziliensis infection was assessed in 79 of the 138 patients with cutaneous leishmaniasis who attended a reference outpatient unit in manaus, amazonas state, between the august and december of 1997. the disease was characterized by one or more cutaneous ulcers, the skin lesions being frequently associated with satellite lymph-node enlargement. all parasite isolates were identified using monoclonal antibodies and enzyme electrophoresis. only two (2.8%) of t ...200212080973
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
new pcr assay using glucose-6-phosphate dehydrogenase for identification of leishmania species.glucose-6-phosphate dehydrogenase (g6pd) is one of the multilocus enzymes used to identify leishmania by zymodeme analysis. the polymorphic pattern revealed by partial characterization of the gene encoding g6pd generated molecular markers useful in the identification of different leishmania species by pcr. initially degenerate oligonucleotides were designed on the basis of data on the conserved active center described for other organisms. primers for reverse transcription-pcr experiments, design ...200312574243
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
th2 responses predominate during the early phases of infection in patients with localized cutaneous leishmaniasis and precede the development of th1 responses.intralesional th2 responses preceded the development of th1 responses in localized cutaneous leishmaniasis due to leishmania guyanensis. although the number of parasites increased in th2 lesions, no correlation was found between the levels of cytokine expression and the number of parasites. in contrast, the decreased number of parasites in th1 lesions is negatively correlated to gamma interferon expression.200312654849
th1 cell development induced by cysteine proteinases a and b in localized cutaneous leishmaniasis due to leishmania guyanensis.the cysteine proteinases cpa and cpb from leishmania major induced th1 responses in patients with leishmaniasis due to leishmania guyanensis. furthermore, cysteine proteinases induced neither interleukin 4 (il-4) nor il-13 and low levels of il-10 in controls and patients. the results suggest that cps would be quite good candidates for a vaccine against different leishmania species.200312704171
structural and functional analysis of an amplification containing a pgpa gene in a glucantime-resistant leishmania (viannia) guyanensis cell line.drug resistance is a complex phenomenon in leishmania and commonly involves gene amplification. active efflux and metal sequestration through a p-glycoprotein have been pointed to as the major mechanisms used by drug-resistant leishmania. a gene amplification from a glucantime-resistant leishmania (viannia) guyanensis cell line was characterised in an attempt to understand the mechanism of metal resistance in this pathogenic species. we show that the amplification is present as an extrachromosom ...200312756544
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
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
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
american cutaneous leishmaniasis, lepromatous leprosy, and pulmonary tuberculosis coinfection with downregulation of the t-helper 1 cell response.cutaneous leishmaniasis, leprosy, and tuberculosis are caused by intracellular pathogens whose development depends on impaired cell-mediated immunity. we report an exceptional triple association of american cutaneous leishmaniasis, lepromatous leprosy, and pulmonary tuberculosis in a man with no recognized immunodeficiency. normal immunological assessment of the interferon-gamma pathway does not support the hypothesis of a genetic defect in any of the genes involved in the t helper (th)-1 cytoki ...200312942392
comparative biology of two populations of lutzomyia umbratilis (diptera: psychodidae) of central amazonia, brazil, under laboratory conditions.lutzomyia umbratilis is the main vector of cutaneous leishmaniasis due to leishmania guyanensis in northern south america. it has been found naturally infected with this species of leishmania only east of the rio negro and north of the rio amazonas. however, populations of this sand fly species are also present in areas south of the amazon river system, which may act as a geographical barrier to the leishmania guyanensis cycle. with the aim of looking for possible biological differences between ...200415462295
antibody response in patients with cutaneous leishmaniasis infected by leishmania (viannia) braziliensis or leishmania (viannia) guyanensis in brazil.the antibody response against leishmania (leishmania) amazonensis crude antigen was measured through the indirect immunofluorescent assay (ifa) and the immunoenzymatic assay (elisa) in 114 patients with cutaneous leishmaniasis (cl) in brazil. fifty-four patients were infected by leishmania (viannia) braziliensis, and 60 patients had l. (v.) guyanensis infection. patients were comparable by age, sex, disease duration and the montenegro skin test diameter. l. (v.) braziliensis-infected patients sh ...200515589797
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
comparative protein profiling identifies elongation factor-1beta and tryparedoxin peroxidase as factors associated with metastasis in leishmania guyanensis.parasites of the leishmania viannia subgenus are major causative agents of mucocutaneous leishmaniasis (mcl), a disease characterised by parasite dissemination (metastasis) from the original cutaneous lesion to form debilitating secondary lesions in the nasopharyngeal mucosa. we employed a protein profiling approach to identify potential metastasis factors in laboratory clones of l. (v.) guyanensis with stable phenotypes ranging from highly metastatic (m+) through infrequently metastatic (m+/m-) ...200616325936
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
molecular epidemiology of leishmania (viannia) guyanensis in french guiana.little information is available about the genetic variability of leishmania populations and the possible correlations with ecoepidemiological features of leishmaniases. the present study was carried out in french guiana, a country where cutaneous leishmaniases (cl) are endemic over the whole territory. the genetic polymorphism of a nuclear sequence encompassing the end of the ribosomal small subunit and the internal transcribed spacer 1 of 265 isolates from patients with cl was examined by restr ...200616455900
[management of cutaneous leishmaniasis in adults and children].cutaneous leishmaniasis can present a variety of clinical features and courses. the causative leishmania species is an important prognostic factor in immunocompetent patients. local treatment modalities including topical paromomycin, cryotherapy, localized controlled heat, carbon dioxide laser therapy, or intralesional meglumine antimoniate can be effective against leishmania major or leishmania tropica. oral fluconazole may be a second-line treatment. parenteral antimonials are useful for persi ...200516465821
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
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
leishmaniasis among gold miners, french guiana. 200616848045
[outbreak of cutaneous leishmaniasis in military population coming back from french guiana].an outbreak of cutaneous leishmaniasis occurred among 71 soldiers who had participated in various missions during a 4-month's period in french guiana. the aims of this study were (i) to describe outbreak and (ii) to determine risk factors of cutaneous leishmaniasis.200616902382
[trypanosomatidae of public health importance occurring in wild and synanthropic animals of rural venezuela].chagas disease and leishmaniasis are important public health problems due to their high frequency and broad distribution in latin america. understanding of the roles of reservoir animals is crucial for a global assessment of the epidemiology of these diseases.200616929902
species diversity causing human cutaneous leishmaniasis in rio branco, state of acre, brazil.information on leishmania species diversity in western brazilian amazon and the clinical picture of human cutaneous leishmaniasis it causes is scarce. we describe clinical findings, diagnostic procedures and identification of leishmania species in patients from that region.200616930261
selective expression of the v beta 14 t cell receptor on leishmania guyanensis--specific cd8+ t cells during human infection.peripheral blood mononuclear cells from subjects never exposed to leishmania were stimulated with leishmania guyanensis. we demonstrated that l. guyanensis-stimulated cd8(+) t cells produced interferon (ifn)- gamma and preferentially expressed the v beta 14 t cell receptor (tcr) gene family. in addition, these cells expressed cutaneous lymphocyte antigen and ccr4 surface molecules, suggesting that they could migrate to the skin. results obtained from the lesions of patients with localized cutane ...200717262718
single and concomitant experimental infections by endotrypanum spp. and leishmania (viannia) guyanensis (kinetoplastida: trypanosomatidae) in the neotropical sand fly lutzomyia longipalpis (diptera: psychodidae).lutzomyia longipalpis females received single and mixed infections with endotrypanum and leishmania. two biological parameters were analyzed: the percentage of infected females and the distribution of flagellates in the gut of the females. the principal comparisons were performed between (1) two strains of endotrypanum, (2) cloned versus primary sample of one strain of endotrypanum, (3) endotrypanum versus leishmania guyanensis, and (4) the pattern of flagellates behaviour by optical microscopy ...200617293978
phlebotomine sand flies (diptera: psychodidae) associated with changing patterns in the transmission of the human cutaneous leishmaniasis in french guiana.between march 2000 and december 2001 a survey of the sand flies (diptera: phlebotominae) of french guiana was carried out during 14 nights of captures with cdc light-traps and malaise traps, and resulted in the collection of 2245 individuals of 38 species. the most abundant species were lutzomyia (trichophoromyia) ininii floch & abonnenc, lu.(psychodopygus) squamiventris maripaensis floch & abonnenc, and lu .(nyssomyia) flaviscutellata mangabeira. half of the collected sand flies females were di ...200717293996
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