isoenzyme characterization of leishmania braziliensis braziliensis isolates obtained from bolivian and peruvian patients.thirty-four leishmania isolates obtained from bolivian and peruvian patients infected with mucocutaneous leishmaniasis were characterized by isoenzyme electrophoresis using 10 enzymatic markers; all belonged to the subspecies l.b. braziliensis. three isolates showed marked variation compared with the reference strain with respect to 5 or 6 enzymes. these variant isolates originated from patients with forms of the disease which were unresponsive to treatment.19921440812
genetic heterogeneity in peruvian leishmania isolates.leishmania were isolated from peruvian patients with uta or espundia; genomic dna was examined for restriction fragment length differences by southern blot analysis using dna probes for beta-tubulin and for the major surface antigen gp63. using 5 different restriction endonucleases, peruvian isolates show homogeneity when examined at the beta-tubulin locus. in contrast, the organisms demonstrated heterogeneity both within and between disease groups when examined for restriction site differences ...19892572179
the use of nonradioactive dna probes for the characterization of leishmania isolates from peru.we describe conditions for dot blot dna hybridization studies using biotinylated kdna probes from leishmania. the sensitivity and specificity attained with biotinylated or 32p-labeled probes were equivalent. the lower level of detection obtained was 100 parasites that were blotted on nitrocellulose paper and then treated with proteinase k. studies were performed with 112 leishmania isolates from andean (uta) and sylvatic mucocutaneous (espundia) patients and all were determined to belong to the ...19883354765
leishmania (viannia) lainsoni: first isolation in peru.surveys were conducted from 1986 through 1992 to define the etiology and geographic distribution of human leishmaniasis in peru. lesion aspirates and skin biopsies were obtained from clinically diagnosed cases of leishmaniasis and tested for promastigotes by standard culture techniques. the isozyme profile of the isolates was determined by the cellulose acetate electrophoresis technique. data indicated that the isozyme profiles for leishmania isolates from six patients were similar to that of re ...19947985744
molecular karyotype variation in leishmania (viannia) peruviana: indication of geographical populations in peru distributed along a north-south cline.forty-one leishmania peruviana isolates were selected along a north-south transect which crossed areas endemic for uta in three different biogeographical regions in the peruvian andes. the isolates were analysed by molecular karyotyping and hybridization with three chromosome-derived dna probes. all the isolates could be distinguished from l. braziliensis by their plb-134 hybridization patterns. however, the patterns with the other probes (plb-168 and -22) could be used to cluster the peruvian i ...19938250624
recombinant antigens for specific and sensitive serodiagnosis of latin american tegumentary leishmaniasis.the diagnostic potential of recombinant leishmanial antigens for latin american tegumentary leishmaniasis (latl) was examined. two leishmania (viannia) peruviana recombinant proteins, t26-u2 and t26-u4, were assessed by their reactivity to detect specific anti-leishmanial antibodies. seventy-eight individual sera from persons with latl, 39 from those with other diseases, and 10 negative control sera were tested by western blotting and enzyme-linked immunosorbent assay. the sensitivity of the tes ...19979580116
comparison of chromosome and isoenzyme polymorphism in geographical populations of leishmania (viannia) peruviana.five chromosomes and 17 isoenzyme loci were analysed in 4 allopatric populations of leishmania (viannia) peruviana, and molecular distances calculated with 2 estimators, chromosomal size difference index and jaccard distance. chromosome and isoenzyme data were in overall concordance: 13/30 isolates clustered similarly on the dendrograms constructed from the different estimators, and a significant correlation (p < 0.001) was observed between the molecular distances calculated from the two sets of ...19989881379
size-polymorphism of mini-exon gene-bearing chromosomes among natural populations of leishmania, subgenus order to explore genomic plasticity at the level of the mini-exon gene-bearing chromosome in natural populations of leishmania, the molecular karyotype of 84 leishmania stocks belonging to subgenus viannia, originating mostly from peru and bolivia, and differing according to eco-geographical and clinical parameters, was resolved and hybridised with a mini-exon probe. the results suggest that size variation of the mini-exon gene-bearing chromosome is frequent and important (up to 245-kb size-d ...199910428631
natural infections of leishmania peruviana in animals in the peruvian andes.evidence that domestic dogs may act as reservoir hosts for cutaneous leishmaniasis in the peruvian andes is provided by the isolation, for the first time, from naturally infected dogs of parasites identified (by isoenzymes) as leishmania peruviana. leishmania parasites were isolated from nasal aspirates or biopsies from 5 (1.8%) of 279 asymptomatic dogs samples in endemic villages of the peruvian andes. in addition, leishmania (viannia) infections were identified in 15 (5.4%) of 276 nasal sample ...199910492779
use of pcr to detect leishmania (viannia) spp. in dog blood and bone marrow.a pcr-based protocol for the detection of leishmania (viannia) parasites in canine blood, buffy coat, and bone marrow was developed and was then tested with field samples taken from a random sample of 545 dogs from villages in peru where leishmania (viannia) braziliensis and leishmania (viannia) peruviana are endemic. comparative tests with cultured parasites mixed with dog blood showed that the pcr assay's sensitivity was significantly dependent on the dna extraction protocol and the pcr primer ...200010655379
is leishmania (viannia) peruviana a distinct species? a mlee/rapd evolutionary genetics answer.a set of 38 leishmania stocks from the andean valleys of peru was characterized by both multilocus enzyme electrophoresis (mlee) and random amplified polymorphic dna (rapd). data were analyzed in terms of taxonomy and evolutionary genetics. synapomorphic mlee and rapd characters, clear-cut clustering, and strong agreement between the phylogenies inferred from either mlee or rapd supported the view that leishmania (viannia) peruviana and leishmania (viannia) braziliensis correspond to two closely ...200010847336
american cutaneous leishmaniasis in domestic dogs: an example of the use of the polymerase chain reaction for mass screening in epidemiological studies.domestic dogs (canis familiaris) are firmly incriminated as reservoir hosts of zoonotic visceral leishmaniasis. as an increasing number of studies have reported high infection rates with american cutaneous leishmaniasis (acl) in dogs, it is suggested that they should also be incriminated as reservoir hosts of acl. the evidence to incriminate dogs as acl reservoir hosts is reviewed, and we conclude that there is, as yet, only circumstantial evidence to support that claim, one of the reasons being ...200212055824
direct identification of leishmania species in biopsies from patients with american tegumentary leishmaniasis.accurate identification of leishmania species is important for monitoring clinical outcome, adequately targeting treatment, and evaluation of epidemiological risk in tegumentary leishmaniasis. this is especially the case in regions where several species coexist and for travel medicine where the geographical source of infection is not always obvious. species identification presently depends on parasite isolation, which is not very sensitive and not necessarily representative of parasites actually ...200312886810
comparison of meglumine antimoniate and pentamidine for peruvian cutaneous leishmaniasis.pentamidine was compared with meglumine antimoniate (glucantime) for 80 patients with cutaneous leishmaniasis due to leishmania braziliensis in peru. of the 40 patients administered glucantime (20 mg of antimony [sb]/kg/day intravenously for 20 days), 31 cured (78%), 6 failed (15%), of which 5 were due to relapse, and 3 were lost to follow-up (7%). of the 40 patients administered pentamidine (2 mg/kg every other day for seven injections), 14 were cured (35%), 23 failed (58%), and 3 were lost to ...200515741547
influence of leishmania (viannia) species on the response to antimonial treatment in patients with american tegumentary leishmaniasis.pentavalent antimonials (sbv) are the first-line chemotherapy for american tegumentary leishmaniasis (atl). there are, however, reports of the occurrence of treatment failure with these drugs. few studies in latin america have compared the response to sbv treatment in atl caused by different leishmania species.200717492601
evaluation of an in vitro and in vivo model for experimental infection with leishmania (viannia) braziliensis and l. (v.) peruviana.leishmania (viannia) braziliensis and l. (v.) peruviana are two parasite species characterized by a very different pathogenicity in humans despite a high genetic similarity. we hypothesized previously that l. (v.) peruviana would descend from l. (v.) braziliensis and would have acquired its 'peruviana' character during the southward colonization and adaptation of the transmission cycle in the peruvian andes. in order to have a first appreciation of the differences in virulence between both speci ...200817961284
clinical and parasite species risk factors for pentavalent antimonial treatment failure in cutaneous leishmaniasis in peru.treatment for cutaneous leishmaniasis (cl) with standard pentavalent antimonial therapy is hampered by cumbersome administration, toxicity, and potential failure. knowledge of factors influencing treatment outcome is essential for successful management.200818171254
extreme inbreeding in leishmania braziliensis.leishmania species of the subgenus viannia and especially leishmania braziliensis are responsible for a large proportion of new world leishmaniasis cases. the reproductive mode of leishmania species has often been assumed to be predominantly clonal, but remains unsettled. we have investigated the genetic polymorphism at 12 microsatellite loci on 124 human strains of leishmania braziliensis from 2 countries, peru and bolivia. there is substantial genetic diversity, with an average of 12.4 +/- 4.4 ...200919497885
a battery of 12 microsatellite markers for genetic analysis of the leishmania (viannia) guyanensis complex.we used 12 microsatellite markers developed for leishmania braziliensis to genotype 28 strains of the main species of the leishmania guyanensis complex (i.e. l. guyanensis and l. panamensis) collected in ecuador and peru. the important heterozygote deficits observed in these populations are similar with the previous data obtained in l. braziliensis and raise again the debate on the reproductive mode of these protozoan parasites. the data showed genetic polymorphism and geographical differentiati ...201020609264
use of fta cards for direct sampling of patients' lesions in the ecological study of cutaneous leishmaniasis.the fta card (whatman) was assessed for its utility as a molecular epidemiological tool in collecting samples from patients with leishmaniasis in peru because the card has a variety of merits; it is less invasive for patients and easy to handle for both physicians and other medical personnel for sample collection or diagnosis, in addition to its simplicity and easy countrywide and/or intercountry transportation for analysis. samples were collected from 132 patients suspected of having leishmania ...201020720027
polymerase chain reaction detection of leishmania kdna from the urine of peruvian patients with cutaneous and mucocutaneous leishmaniasis.we hypothesized that leishmania kdna may be present in urine of patients with cutaneous leishmaniasis (cl). urine samples and standard diagnostic specimens were collected from patients with skin lesions. kdna polymerase chain reaction (pcr) was performed on samples from patients and 10 healthy volunteers from non-endemic areas. eighty-six of 108 patients were diagnosed with cl and 18 (21%) had detectable leishmania viannia kdna in the urine. sensitivity and specificity were 20.9% (95% confidence ...201121460009
multilocus genotyping reveals a polyphyletic pattern among naturally antimony-resistant leishmania braziliensis isolates from order to understand the epidemiological dynamics of antimonial (sb(v)) resistance in zoonotic tegumentary leishmaniasis and its link with treatment outcome, we analyzed the population structure of 24 peruvian leishmania braziliensis clinical isolates with known in vitro antimony susceptibility and clinical phenotype by multilocus microsatellite typing (14 microsatellite loci). the genetic variability in the peruvian isolates was high and the multilocus genotypes were strongly differentiated f ...201121871584
leishmania (viannia) species identification on clinical samples from cutaneous leishmaniasis patients in peru: assessment of a molecular stepwise approach.we present an algorithm based on three pcr assays for leishmania (viannia) species identification and assessed its performance using 70 specimens from peruvian patients. the succession of the assayed targets can be ordered according to species prevalence. sequential progression through the algorithm reduced the number of samples here studied by approximately 30% after each step.201122116151
acute new world cutaneous leishmaniasis presenting as tuberculoid granulomatous dermatitis.acute primary cutaneous leishmaniasis typically presents microscopically with a lymphohistiocytic infiltrate containing admixed plasma cells, parasitized macrophages and abundant organisms. tuberculoid granulomatous changes may occur in the later phases of primary infection. a 23-year-old male presented 1 month after visiting peru with classic clinical findings of acute primary cutaneous leishmaniasis, while histopathology showed a tuberculoid granulomatous process that lacked any organisms in h ...201222236114
association of the endobiont double-stranded rna virus lrv1 with treatment failure for human leishmaniasis caused by leishmania braziliensis in peru and bolivia.cutaneous and mucosal leishmaniasis, caused in south america by leishmania braziliensis, is difficult to cure by chemotherapy (primarily pentavalent antimonials [sb(v)]). treatment failure does not correlate well with resistance in vitro, and the factors responsible for treatment failure in patients are not well understood. many isolates of l. braziliensis (>25%) contain a double-stranded rna virus named leishmaniavirus 1 (lrv1), which has also been reported in leishmania guyanensis, for which a ...201626123565
outbreak of cutaneous leishmaniasis in peruvian military personnel undertaking training activities in the amazon basin, 2010.military personnel deployed to the amazon basin are at high risk for cutaneous leishmaniasis (cl). we responded to an outbreak among peruvian army personnel returning from short-term training in the amazon, conducting active case detection, lesion sample collection, and risk factor assessment. the attack rate was 25% (76/303); the incubation period was 2-36 weeks (median = 8). most cases had one lesion (66%), primarily ulcerative (49%), and in the legs (57%). real-time polymerase chain reaction ...201526078320
genetic divergence in populations of lutzomyia ayacuchensis, a vector of andean-type cutaneous leishmaniasis, in ecuador and peru.haplotype and gene network analyses were performed on mitochondrial cytochrome oxidase i and cytochrome b gene sequences of lutzomyia (lu.) ayacuchensis populations from andean areas of ecuador and southern peru where the sand fly species transmit leishmania (leishmania) mexicana and leishmania (viannia) peruviana, respectively, and populations from the northern peruvian andes, for which transmission of leishmania by lu. ayacuchensis has not been reported. the haplotype analyses showed higher in ...201525312337
[specificity of the intradermal montenegro test in patients infected by trypanosoma cruzi from different regions of peru].in order to assess the specificity of the leishmanin skin test in chagas disease patients without clinical history of leishmaniasis, present or former. a sample of 102 persons infected with trypanosoma cruzi (14 acute cases with parasitological diagnosis and 88 chronic cases) through the demonstration of igg antibodies by elisa and indirect immunofluorescence (iif) were evaluated with leishmanin soluble antigen which contained leishmania (viannia) peruviana concentration of 25-30 ug/ml. only fiv ...201425123866
native rodent species are unlikely sources of infection for leishmania (viannia) braziliensis along the transoceanic highway in madre de dios, estimated 2.3 million disability-adjusted life years are lost globally from leishmaniasis. in peru's amazon region, the department of madre de dios (mdd) rises above the rest of the country in terms of the annual incidence rates of human leishmaniasis. leishmania (viannia) braziliensis is the species most frequently responsible for the form of disease that results in tissue destruction of the nose and mouth. however, essentially nothing is known regarding the reservoirs of this vector-borne, ...201425062033
accurate and rapid species typing from cutaneous and mucocutaneous leishmaniasis lesions of the new world.the heat-shock protein 70 gene (hsp70) has been exploited for leishmania species identification in the old and new world, using polymerase chain reaction (pcr) followed by restriction fragment length polymorphism analysis. three new leishmania-specific hsp70 pcrs were recently described, and we applied 2 of these on 89 clinical samples from a total of 73 peruvian patients with either cutaneous or mucocutaneous leishmaniasis. the new pcrs on average showed a 2- to 3-fold improved sensitivity in t ...201222819605
comparative zymographic analysis of metallopeptidase of leishmania (viannia) peruviana and leishmania (viannia) braziliensis isolates from peru.american tegumentary leishmaniasis (atl) in peru is mainly associated with leishmania (viannia) peruviana and l. (v.) braziliensis. these parasites are genetically related, and their characterization as distinct species is controversial. despite their genetic similarity, each species is associated with different clinical manifestations of atl; l. (v.) peruviana causes only cutaneous leishmaniasis, whereas l. (v.) braziliensis can cause both cutaneous and mucocutaneous leishmaniasis. because the ...201222562004
evolution of the leishmania braziliensis species complex from amplified fragment length polymorphisms, and clinical order to get more insight into its evolution and geographical distribution, we investigated the leishmania (viannia) braziliensis species complex using amplified fragment length polymorphisms and sequencing of a heat-shock protein 70 gene fragment. previously, several assays had alluded to the high genetic diversity of the group, and single-locus assays typically identified two species, i.e. l. braziliensis and leishmania peruviana, with occasional genetic signatures of both in the same strai ...201222516226
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