Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| leishmania in phlebotomid sandflies. iv. the transmission of leishmania mexicana amazonensis to hamsters by the bite of experimentally infected lutzomyia longipalpis. | 1977 | 15270 | |
| leishmania in phlebotomid sandflies: vi. importance of hindgut development in distinguishing between parasites of the leishmania mexicana and l. braziliensis complexes. | 1977 | 22860 | |
| leishmaniasis in brazil: x. some observations of intradermal reactions to different trypanosomatid antigens of patients suffering from cutaneous and mucocutaneous leishmaniasis. | in spite of the difficulty of antigen standardization, paired intradermal skin tests demonstrated qualitative differences between leishmanin and in vitro exo-antigen. some of these differences may be due to the destruction of certain antigens by phenol, while others seem to reflect basic antigenic differences. leishmania mexicana amazonensis in vitro exo-antigen produced immediate anaphylactic reponses in 74.4% of the patients with parasitologically proven cutaneous leishmaniasis. although more ... | 1975 | 52214 |
| leishmania mexicana and leishmania tropica: cross immunity in c57bl/6 mice. | 1979 | 88370 | |
| alterations of the immune response associated with chronic experimental leishmaniasis. | balb/c mice infected with leishmania mexicana developed a chronic infection usually accompanied by the appearance of metastatic lesions. throughout the 20 weeks of observation, infected mice ;howed an impairment in both in vivo delayed hypersensitivity response and in vitro lymphocyte reactivity to leishmanial antigen. four to 8 weeks after inoculation infected mice displayed a transitory enhancement of spleen cell responses to phytohemagglutinin p, concanavalin a, and lipopolysaccharide. at the ... | 1979 | 157979 |
| fusion of host cell secondary lysosomes with the parasitophorous vacuoles of leishmania mexicana-infected macrophages. | secondary lysosomes of cultured mouse peritoneal macrophages were labeled with the electron-dense colloid saccharated iron oxide; the identity of the labeled structures was checked by the gomori reaction for acid phosphatase. amastigotes of leishmania mexicana mexicana derived from mouse lesions were used to infect these macrophages in vitro. in electron micrographs of thin sections of infected macrophages the labeled secondary lysosomes were seen fused with the parasitophorous vacuoles without ... | 1975 | 172627 |
| leishmania in phlebotomid sandflies. iii. the ultrastructure of leishmania mexicana amazonensis in the midgut and pharynx of lutzomyia longipalpis. | 1975 | 240164 | |
| epidemiology of dermal leishmaniasis in the rio doce valley, state of minas gerais, brazil. | dermal leishmaniasis is prevalent in the predominantly settled agricultural areas in the rio doce valley in the eastern part of the state of minas gerais, brazil. the disease has been recorded almost equally in both sexes. cases have been confirmed in all age groups but youths aged ten to 14 years form the population segment at greatest risk to infection. cases of single cutaneous lesions, multiple cutaneous lesions and muco-cutaneous lesions have been recorded in the area. isolates of parasites ... | 1979 | 315210 |
| leishmaniasis in brazil: xii. observations on cross-immunity in monkeys and man infected with leishmania mexicana mexicana, l. m. amazonensis, l. braziliensis braziliensis, l. b. guyanensis and l. b. panamensis. | cross-immunity trials in monkeys (cebus apella apella) and observations on experimental and natural infections in man confirm the separate identity of l. mexicana mexicana, l. m. amazonensis, l. b. braziliensis, l. b. guyanensis and l. b. panamensis. neither l. m. mexicana nor l. m. amazonensis infections gave protection against subsequent challenge with parasites of the l. braziliensis complex; but recovery from infection with subspecies of l. braziliensis in most cases gave firm resistance to ... | 1977 | 405504 |
| leishmania braziliensis and leishmania mexicana: experimental cutaneous infections in golden hamsters. | 1979 | 437020 | |
| variations in the response of five strains of mice to leishmania mexicana. | 1979 | 447442 | |
| the effects of protein malnutrition on the course of leishmania mexicana infection in c57bl/6 mice: nutrition and susceptibility to leishmaniasis. | the course of cutaneous infection with leishmania mexicana was studied in normally nourished and protein deprived c57bl/6 mice. mice fed a normal diet showed self-resolving lesions and produced cellular and humoral responses against the parasite. in contrast, mice fed a protein deficient diet which developed chronic protein calorie deficiency failed to recover from l. mexicana infection. non-healing protein deprived mice had depressed delayed hypersensitivity response (dhr) and in vitro lymphocy ... | 1979 | 535184 |
| experimental transmissions of leishmania mexicana amazonesnis lainson & shaw, between hamsters by the bite of lutzomyia flaviscutellata (mangabeira) | 1977 | 560732 | |
| [new observations upon genital lesions caused by leishmania mexicana amazonensis (author's transl)]. | 1978 | 575597 | |
| the colonization of lutzomyia flaviscutellata (diptera: psychodidae), a vector of leishmania mexicana amazonensis in brazil. | 1977 | 609078 | |
| leishmania mexicana and l. tropica: inhibition of growth in mice by concurrent infections of trypanosoma brucei. | 1978 | 627274 | |
| mastomys natalensis as an experimental host for leishmania mexicana mexicana. | young multimammate rats (mastomys natalensis) can be readily infected when inoculated intradermally with the amastigotes of leishmania mexicana mexicana. lesions appear at the site of inoculation in the second week of infection and continue to increase in size for the first month; amastigotes can be detected during this period. in the second month, lesions begin to decrease in size and it is more difficult to detect amastigotes. three months after inoculation, the rats show no sign of infection. ... | 1978 | 653786 |
| leishmania tropica and leishmania mexicana: cross-immunity in mice. | 1978 | 668843 | |
| unusual axonemal doublet arrangements in the flagellum of leishmania amastigotes. | studies on the fine structure of leishmania mexicana, l. enriettii and l. tropica major have revealed several unusual arrangements of microtubules in the flagellar axoneme. the anterior end of the flagellum in these three species was found to contain disarranged axonemal doublets (d) in the absence of the two central singlets(s). leishmania amastigotes do not use their flagellum as do promastigotes for propulsion, and persistence of the usual 9d and 2s microtubular arrangement may not be necessa ... | 1978 | 705841 |
| isolation of the intracellular stages of leishmania mexicana amazonensis using cellulose column. | 1978 | 736664 | |
| [dissemination of leishmania mexicana amazonensis by intracardiac inoculation by pretreatment with gastric mucin (author's transl)]. | 1978 | 757721 | |
| the resistance of intracellular leishmania parasites to digestion by lysosomal enzymes. | infections of leishmania mexicana in cultured normal mouse peritoneal macrophages show different morphological features depending on whether the parasites invade as promastigote or amastigote forms. infections derived from promastigote invasion are characterized by parasitophorous vacuoles which develop slowly, and acquire only modest proportions. in contrast, the organisms in amastigote-derived infections lie within parasitophorous vacuoles which develop more rapidly, and attain a much greater ... | 1977 | 921365 |
| antileishmanial effect of allopurinol. ii. relationship of adenine metabolism in leishmania species to the action of allopurinol. | allopurinol was shown to be effective in vitro against leishmania mexicana and leishmania donovani as well as against leishmania braziliensis. the major metabolic derivative of allopurinol in humans, oxipurinol, also is antileishmanial for l. donovani. the antileishmanial effect of allopurinol and oxipurinol can be specifically reversed by adenine, and its metabolic precursors and derivatives, but by no other purines or their derivative. it is proposed that the adenylosuccinate synthetase or the ... | 1977 | 925380 |
| effect of sodium stibogluconate and pyrimethamine on mouse infections with leishmania mexicana. | 1976 | 938127 | |
| partial purification of amastigotes from cutaneous lesions of american leishmaniasis. | amastigotes of leishmania mexicana, l. mexicana amazonensis, l. brasiliensis, and l. enriettii were isolated from lesions in infected animals. numbers of amastigotes recovered ranged from 1 x 10(7) to 7 x 10(8), depending on the strain of leishmania. trypsinization disassociated the lesions and released the parasites. after 18 to 24 hr incubation at 37 c in tissue culture media with antibiotics, many of the intact host cells attached to the flask. amastigotes were collected from the media in rel ... | 1976 | 978350 |
| effect of the antiphagocytic agent cytochalasin b on macrophage invasion by leishmania mexicana promastigotes and trypanosoma cruzi epimastigotes. | unstimulated mouse peritoneal exudate cells were cultured on coverslips in medium 199 containing 10 per cent (v/v) calf serum. cytochalasin b dissolved in dimethyl sulphoxide (dmso) and diluted in medium 199 was added to cultures to give final concentrations of 1, 5 and 10 mug/ml. equal numbers of leishmania mexicana promastigotes, trypanosoma cruzi epimastigotes and sheep red cells were added to 24 hr cultures incubated at 37 c. the macrophage monolayers were fixed and stained at various time i ... | 1975 | 1097661 |
| electrophoretic investigation of some dehydrogenases in leishmania amastigotes. | amastigotes of leishmania mexicana mexicana and of leishmania donovani were grown in mouse peritoneal macrophages and dog sarcoma cells in culture. polyacrylamide gel disc electrophoresis of amastigote-infected tissue cultures failed to detect parasite lactate dehydrogenase and malate dehydrogenase, although the presence of glucose-6-phosphate dehydrogenase was indicated. | 1975 | 1155996 |
| antigenic differences among leishmania amazonensis isolates and their relationship with distinct clinical forms of the disease. | immunoblot analysis was used to investigate antigenic differences among clinical isolates of leishmania amazonensis and their role in the etiology of the disease. western blots of promastigote homogenates were analyzed with either monoclonal antibodies (mabs) specific for the l. mexicana complex (m-4, m-6, m-9, and m-11) or polyclonal sera from l. amazonensis infected patients with the various forms of clinical disease. in the case of the mabs, no significant variation was observed among the str ... | 1992 | 1284990 |
| indirect fluorescent antibody test in the serodiagnosis of visceral leishmaniasis in bangladesh. | indirect fluorescent antibody test (ifat) was found to be 100% sensitive and 100% specific when tested with sera from 125 parasitologically proven kala-azar patients, 100 healthy controls and 50 sick control cases. promastigotes of both l. enriettii and l. donovani as well as amastigotes of l. enriettii were found equally satisfactory as antigen for ifat. from the results of the present study, it is concluded that ifat is a highly sensitive as well as specific serological test for the diagnosis ... | 1992 | 1303085 |
| placebo-controlled clinical trial of sodium stibogluconate (pentostam) versus ketoconazole for treating cutaneous leishmaniasis in guatemala. | to determine the relative efficacy and toxicity of stibogluconate and ketoconazole for the treatment of cutaneous leishmaniasis, a comparative trial was conducted in which 120 guatemalan men with parasitologically proven cutaneous leishmaniasis were randomly divided into three treatment groups: sodium stibogluconate (20 mg of antimony per kilogram per day intravenously for 20 days), ketoconazole (600 mg per day orally for 28 days), and placebo. treatment outcome was influenced by species. among ... | 1992 | 1311351 |
| drug resistance in leishmaniasis: its implication in systemic chemotherapy of cutaneous and mucocutaneous disease. | we report that in vitro sensitivity to pentavalent antimony (sb5) of 35 leishmania isolates as determined by the semiautomated microdilution technique (samt) showed an 89% and 86% correlation with clinical outcome after pentostam and glucantime treatment, respectively. these results suggest that in over 85% of the cases, the clinical outcome of treatment (cure or failure) could have been predicted by using the samt technique. furthermore, the results clearly indicate that drug resistance is a pr ... | 1992 | 1322070 |
| leishmaniasis in a heart transplant patient. | infection is a well-recognized complication of immunosuppressive therapy. we describe a case of leishmaniasis in a 62-year-old man who was undergoing immunosuppressive therapy because of heart transplantation. a geologist and native texan, the patient had traveled extensively in south-central texas, but not outside of the continental united states. cutaneous lesions of the extremities developed, which were diagnosed histologically as leishmaniasis and confirmed by means of transmission electron ... | 1992 | 1323332 |
| the 63-kilobase circular amplicon of tunicamycin-resistant leishmania amazonensis contains a functional n-acetylglucosamine-1-phosphate transferase gene that can be used as a dominant selectable marker in transfection. | tunicamycin (tm)-resistant leishmania amazonensis has been found previously to contain amplified chromosomal dna, existing exclusively as extrachromosomal circles of 63 kb. fragments of this dna cloned into plasmids were functionally analyzed by transfection of wild-type cells. a clone with a 15-kb fragment of the 63-kb circle was initially found to confer tm resistance. a library of the 15-kb fragment was then prepared and used in toto to transfect wild-type cells. the transfectants that emerge ... | 1992 | 1324414 |
| a shuttle vector which facilitates the expression of transfected genes in trypanosoma cruzi and leishmania. | a trypanosoma cruzi expression vector has been constructed using sequences derived from the flanking regions of the glyceraldehyde 3-phosphate dehydrogenase (ggapdh) genes. the neomycin phosphotransferase (neor) gene was incorporated as a selectable marker. using electroporation we have introduced this vector into both t. cruzi and leishmania cells and conferred g418 resistance. transformation is mediated by large extrachromosomal circular elements composed of head-to-tail tandem repeats of the ... | 1992 | 1324472 |
| characterization of sequence changes in kinetoplast dna maxicircles of drug-resistant leishmania. | we have compared kinetoplast dna maxicircles of tunicamycin- and arsenite-resistant variants of repeatedly cloned leishmania mexicana amazonensis showing dna amplification with wild-type and arsenite-resistant variants of the same lineage that do not show dna amplification. dna restriction patterns and the degree of cross-hybridization between maxicircle dna fragments of parasites displaying dna amplification and those of parasites without amplification were examined. in addition, the nucleotide ... | 1992 | 1336569 |
| 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 ... | 1992 | 1339971 |
| enhancement of leishmania amazonensis infection in bcg non-responder mice by bcg-antigen specific vaccine. | different patterns of cutaneous leishmaniasis can be induced when a challenge of alike dose of leishmania amazonensis amastigotes in various inbred strains was applied. two strains of mice, the balb/c and c57bl/10j, showed exceptional susceptibility, and 10(6) amastigotes infective dose lead, to ulcerative progressive lesions with cutaneous metastasis and loss by necrosis of leg on which the footpad primary lesion occurred. lesions were also progressive but in a lower degree when c3h/hen and c57 ... | 1992 | 1343799 |
| transkinetoplastidy--a novel phenomenon involving bulk alterations of mitochondrion-kinetoplast dna of a trypanosomatid protozoan. | dramatic and consistent changes of mitochondria or kinetoplast dna (kdna) were observed in certain variants of leishmania amazonensis (a variants) selected in vitro for arsenite-resistance. this was found initially by comparing different lots of wild-type cells and their respective a variants resistant to 30 microm arsenite. the kdnas isolated from these two groups had different restriction patterns and hybridized poorly to each other, whereas those from different lots within each of the two gro ... | 1992 | 1348540 |
| american leishmania spp. and trypanosoma cruzi: galactosyl alpha(1-3) galactose epitope localization by colloidal gold immunocytochemistry and lectin cytochemistry. | patients with chagas' disease or different clinical forms of leishmaniasis (cutaneous or visceral) have elevated galactosyl alpha (1-3)galactose antibodies. using colloidal gold immunocytochemistry--monoclonal antibody gal-13 (specific for lipid-linked galactosyl alpha (1-3)galactose residues) and anti-nidogen antibodies and lectin cytochemistry (bandeiraea simplicifolia ib4), both techniques specific for demonstrating galactosyl alpha (1-3)galactose residues--we have found terminal disaccharide ... | 1992 | 1370418 |
| inhibition of mouse lymphocyte proliferative response by glycosphingolipids from leishmania (l.) amazonensis. | the effect of a purified preparation of glycosphingolipids (gsls) extracted from leishmania (l.) amazonensis amastigotes on murine lymphocytes was investigated. gsls inhibited both concanavalin a (con a)- or lipopolysaccharide-induced [3h]thymidine uptake by normal and immunized balb/c mouse lymph node cells. the effect of total gsls was dose dependent. total gsls also suppressed the two-way mixed lymphocyte reaction of balb/c x c57bl/6 cells and the antigen-specific response of immunized mouse ... | 1992 | 1386324 |
| characterization of a multi-copy gene for a major stage-specific cysteine proteinase of leishmania mexicana. | lmcpb, a gene from leishmania mexicana that encodes a major cysteine proteinase in the parasite, has been cloned and sequenced. lmcpb is related more to cysteine proteinases from trypanosoma brucei and trypanosoma cruzi than to a previously characterized cysteine proteinase, lmcpa, of l. mexicana. it contains a long c-terminal extension characteristic of similar enzymes of t. brucei and t. cruzi. the gene is multi-copy and tandemly arranged. lmcpb rna levels are developmentally regulated with st ... | 1992 | 1397299 |
| is leishmaniasis ever cured? | the persistence of parasites in mice cured of leishmania mexicana infection was investigated by using immunosuppressive drugs and checking for the reappearance of lesions. balb/c (susceptible) and c57bl/6 (partially resistant) mice infected with 10(4) amastigotes were treated with either thermotherapy or meglumine antimonate and subsequently immunosuppressed with either cyclophosphamide or hydrocortisone. immunosuppression by either method caused lesions to reappear in both strains of mice regar ... | 1992 | 1412645 |
| differential regulation of putrescine uptake in trypanosoma cruzi and other trypanosomatids. | putrescine uptake in trypanosoma cruzi epimastigotes is 10 to 50-fold higher than in leishmania mexicana or crithidia fasciculata. polyamine transport in all these trypanosomatids is an energy-dependent process strongly inhibited by the presence of 2,4-dinitrophenol or kcn. putrescine uptake in t. cruzi and l. mexicana was markedly decreased by the proton ionophore carbonylcyanide m-chlorophenylhydrazone but it was not affected by ouabain, a na(+)-k+ pump inhibitor. the depletion of intracellula ... | 1992 | 1417835 |
| diffuse cutaneous leishmaniasis with atypical aspects. | a 16-year-old man had long-standing diffuse cutaneous leishmaniasis with the following characteristics: diffuse infiltrated lesions rich in amastigotes, absence of mucosal involvement, and lack of parasite-specific cell-mediated immune response. in situ identification of leishmania mexicana amazonensis was achieved by the use of monoclonal antibodies. clinically, as an atypical finding there was deep and extensive ulceration in the lower limbs. histologically, an atypical characteristic was the ... | 1992 | 1428449 |
| hydrolysis of l-leucine methyl ester by leishmania mexicana mexicana amastigote cysteine proteinases. | the main cysteine proteinases of the amastigote form of leishmania mexicana mexicana were partially purified by gel filtration and ion exchange chromatography. the latter procedure resulted in the separation of some individual cysteine proteinases, as demonstrated by gelatin-sodium dodecyl sulphatepolyacrylamide gel electrophoresis. fractions containing the partially purified proteinases rapidly hydrolysed l-leucine methyl ester to leucine. the activity towards this compound co-eluted with and r ... | 1992 | 1428504 |
| creation of null/+ mutants of the alpha-tubulin gene in leishmania enriettii by gene cluster deletion. | tubulins are abundant structural proteins in the leishmania parasite, and tubulin genes are examples of highly expressed genes, which are present in multiple copies arranged in tandem repeats. functional analysis of such multicopy genes using genetic manipulation has not yet been possible. here we describe a method for creating deletions of alpha-tubulin gene clusters by targeted gene replacement and report the isolation of null/+ mutants deleted for either of the two allelic tubulin clusters. w ... | 1992 | 1429722 |
| molecular analysis of the cytosolic and glycosomal glyceraldehyde-3-phosphate dehydrogenase in leishmania mexicana. | glyceraldehyde-3-phosphate dehydrogenase (gapdh) activity was detected in two cell compartments of leishmania mexicana promastigotes. these activities could be attributed to two different isoenzymes, one residing in glycosomes, the other in the cytosol. we have cloned and sequenced the genes for both isoenzymes. the glycosomal enzyme is encoded by two tandemly linked genes of identical sequence and contains features frequently found in glycosomal enzymes: the presence of peptide insertions, a sm ... | 1992 | 1435864 |
| dynamics and size polymorphisms of minichromosomes in leishmania major lv-561 cloned lines. | various lines and cloned lines of leishmania major of varying degrees of virulence in balb/c mice possessed size polymorphic multicopy minichromosomes related to previously described ld1/cd1 and 715-class dnas of leishmania. the minichromosomes were not necessary for virulence. two of these dnas (m180 and m210), coexisting in a single cloned line, showed remarkable dynamics in terms of loss or gain when followed through multiple transfers during in vitro culture and in vivo passage in balb/c mic ... | 1992 | 1435877 |
| [cloning of kdna minicircles in different species of leishmania and its use as probes for diagnosis]. | the present study describes the cloning procedure for fragments of kinetoplast dna minicircles from different leishmania species and its use for detecting the presence of these parasites. our methodology was as follow: the dna of the kinetoplast from leishmania mexicana amazonensis and leishmania braziliensis panamensis was extracted, purified and digested with the enzyme dra i. these fragments were cloned in the site for hinc ii in the plasmid pks. e. coli was the bacterial strain used for tran ... | 1992 | 1439001 |
| flow cytometry in the study of the interaction between murine macrophages and the protozoan parasite leishmania amazonensis. | a flow cytometry method was adapted to study interaction between murine macrophages and leishmania amazonensis. using this method it was possible to detect internalization of parasites through an increase in macrophage granularity (side scatter), with the latter indicating the presence of parasites inside parasitophorus vacuoles. a quenching technique was used to confirm the feasibility of the method and to distinguish between internalized and externally attached parasites. experiments using fix ... | 1992 | 1445588 |
| axenic cultivation and characterization of leishmania mexicana amastigote-like forms. | a new method is described which has made possible the long-term axenic cultivation of leishmania mexicana amastigote-like forms in schneider's drosophila medium supplemented with 20% (v/v) foetal calf serum. unlike previous methods, it utilizes direct culture of parasites obtained from the lesions of infected animals rather than adaptation of promastigotes in vitro. ultrastructural (possession of megasomes), biochemical (cysteine proteinase activity and gelatin sds-page banding pattern) and infe ... | 1992 | 1454417 |
| intracellular trafficking and the parasitophorous vacuole of leishmania mexicana-infected macrophages. | the continued success of leishmania as an intramacrophage parasite is dependent on its ability to survive within an acidic intracellular compartment, resist degradation by lysosomal hydrolases, exploit the host cell as a source of nutrients, and avoid the macrophage's antigen-presenting capabilities. all these requirements are dependent on the properties of the parasitophorous vacuole in which leishmania resides. this study shows that the vacuole possesses membrane proteins characteristic of a l ... | 1992 | 1487496 |
| functional and structural damage in leishmania mexicana exposed to the cationic peptide dermaseptin. | the effect of dermaseptin (ds), a 34 amino acid residue cationic peptide isolated from phyllomedusa sauvagii skin, has been studied on promastigotes of leishmania mexicana growing in vitro. within 5 min of incubation in the presence of ds, the flagellated parasites lost their motility. ds inhibited promastigote growth by 50% at a concentration of 3 microm and by 100% at 10 microm. immunocytochemical, freeze fracture, label fracture and electron microscopic observations have shown that the amphip ... | 1992 | 1493807 |
| granulocyte-macrophage colony-stimulating factor increases the infectivity of leishmania amazonensis by protecting promastigotes from heat-induced death. | we have studied the effect of granulocyte-macrophage colony-stimulating factor (gm-csf) on the infectivity of promastigotes of leishmania amazonensis, an obligate intramacrophage parasite. we measured the capacity of the promastigotes to infect macrophages after preincubation at different temperatures (28, 34, and 37 degrees c) with recombinant murine gm-csf, as well as the effect of an anti-murine gm-csf antibody on the in vitro and in vivo infectivity of the parasite. gm-csf increases the capa ... | 1992 | 1500159 |
| dna fingerprints: a tool for identification and determination of the relationships between species and strains of leishmania. | using nonradioactive hybridization, the multilocal probes 33.15, f10 and (cac)5 were shown to recognize multiple minisatellite regions in nuclear dna of leishmania, producing on southern blots complex banding patterns typical of dna fingerprints. we used the 33.15 probe to study 14 different strains belonging to 6 different species from both the sub-genus viannia and the leishmania mexicana complex of the sub-genus leishmania. distinct dna fingerprints were obtained for each strain, permitting t ... | 1992 | 1501645 |
| a developmentally regulated cysteine proteinase gene of leishmania mexicana. | we have isolated a gene encoding a previously unreported class of trypanosomatid cysteine proteinase (cp) from the protozoan parasite leishmania mexicana. the single-copy gene (lmcpa) [corrected]. has several unusual features that distinguish it from cp genes cloned from the related species trypanosoma brucei and trypanosoma cruzi. these include a shorter c-terminal extension of only 10 amino acids and a three-amino-acid insertion, glyvalmet, close to the predicted n-terminus of the mature prote ... | 1992 | 1508041 |
| the dna polymerases of leishmania mexicana. | two previously isolated dna polymerases from the parasitic protozoan leishmania mexicana were further characterized by exposure to inhibitors of mammalian dna polymerases. dna polymerase a, a high molecular mass enzyme, and dna polymerase b, a beta-like dna polymerase were compared to each other and to their mammalian counterparts regarding ph optimum, utilization of templates, and response to various inhibitors and ionic strengths. the results suggest that the dna polymerases from l. mexicana d ... | 1992 | 1516809 |
| stage-specific proteinases of leishmania mexicana mexicana promastigotes. | four distinct bands of cysteine proteinase activity were detected when stationary-phase populations of leishmania mexicana mexicana were subjected to gelatin-sds-page. the highest mobility band contained at least three isoforms separable by mono q anion exchange chromatography. these high mobility activities were distinct from all the major amastigote enzymes. stationary-phase promastigote populations also contained two acid-activable precursor forms of the promastigote-specific band. it is sugg ... | 1992 | 1521760 |
| cystatin-like cysteine proteinase inhibitors of parasitic protozoa. | a new method has been developed for detecting cystatins and other cysteine proteinase inhibitors. the method, which involves protein separation by sds-page followed by a cysteine proteinase overlay step, is more sensitive than previously reported techniques: as little as 1 ng of recombinant human cystatin c can be detected and cysteine proteinase inhibitors could also be detected in complex protein mixtures such as bovine foetal serum. the method has been used to show, for the first time, cystei ... | 1992 | 1526466 |
| a sequence insertion targeting vector for leishmania enriettii. | we have demonstrated previously that leishmania enriettii contains the enzymatic machinery to mediate efficient interplasmidic homologous recombination. in this report we show that a sequence insertion targeting vector, palt-neo-tub, can be inserted into the genome of l. enriettii by homologous recombination between alpha-tubulin sequences found in the plasmid and their homologs in the genome. palt-neo-tub, a pbluescript-derived vector containing the neor gene flanked by the alpha-tubulin interg ... | 1992 | 1537857 |
| the natural history of cutaneous leishmaniasis in guatemala. | the natural history of american cutaneous leishmaniasis was studied in guatemala by analyzing the characteristics of 355 untreated leishmanial lesions, observing the evolution of 57 lesions on persons who received a placebo in treatment trials, and analyzing data from a population-based survey concerning the duration of 82 untreated lesions. of 25 lesions caused by leishmania mexicana that were followed prospectively, 22 (88%) completely reepithelialized by a median lesion age of 14 weeks, and 1 ... | 1992 | 1538157 |
| differential production of granulocyte-macrophage colony-stimulating factor by macrophages from mice susceptible and resistant to leishmania mexicana amazonensis. | the present results demonstrate that macrophages from mice susceptible to infection with leishmania mexicana amazonensis sustain a higher production of granulocyte-macrophage colony-stimulating factor (gm-csf) throughout the in vitro infection than macrophages from a resistant strain. resident macrophages from balb/c and c57b1/10 mice were infected with promastigotes of l. mexicana amazonensis and the amount of biologically active gm-csf was measured in the supernatants collected at different ti ... | 1992 | 1541906 |
| 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 ... | 1992 | 1542309 |
| structure of leishmania mexicana lipophosphoglycan. | lipophosphoglycan (lpg) was isolated from the culture supernatant of leishmania mexicana promastigotes and its structure elucidated by a combination of 1h nmr, fast atom bombardment mass spectrometry, methylation analysis, and chemical and enzymatic modifications. it consists of the repeating phosphorylated oligosaccharides po4-6gal beta 1-4man alpha 1- and po4-6[glc beta 1-3]gal beta 1-4man alpha 1-, which are linked together in linear chains by phosphodiester linkages. each chain of repeat uni ... | 1992 | 1551890 |
| cytokine control of leishmania infection in the balb/c mouse: enhancement and inhibition of parasite growth by local administration of il-2 or il-4 is species and time dependent. | the therapeutic potential of locally injected interleukin-2 (il-2) or interleukin-4 (il-4) was studied in the footpads of leishmania mexicana or leishmania major infected balb/c mice. the disease state was measured both pathologically, by measuring lesion size, and parasitologically, by counting total parasite numbers from infected footpads. il-2 (0.5 microgram/dose) or il-4 (0.1 microgram/dose) was administered either early, 1 day and/or 15 days after infection, or late, after palpable lesions ... | 1992 | 1557229 |
| isolation and partial characterization of a high-molecular-weight dna polymerase from leishmania mexicana. | this paper describes for the first time the isolation and characterization of a high-molecular-weight predominant dna polymerase from the genus leishmania, which are parasitic flagellated protozoa. like mammalian dna polymerase alpha, the leishmanial dna polymerase, designated dna polymerase a, is of high-molecular-weight, is sensitive to n-ethylmaleimide and is inhibited by high ionic strength. unlike mammalian dna polymerase alpha, but similar to the predominant dna polymerase isolated from th ... | 1992 | 1576158 |
| experimental efficiency of phlebotomus papatasi in maintaining development of four species of leishmania. | experimental infections were carried out to evaluate the capability of 3 species of phlebotomus to acquire and allow development of 4 species of leishmania. the sand-flies were allowed to feed on infective blood by a membrane feeding technique and infected vertebrate hosts. the species of phlebotomus experimented with were p. papatasi (egyptian and indian strains), p. dubosqi (sinegal strain), and p. perniciosus (french strain). the species of leishmania used were l. tropica (afganistanian strai ... | 1992 | 1578171 |
| nucleotide sequence of the spliced leader rna gene from leishmania mexicana amazonensis. | 1992 | 1579474 | |
| t-lymphocytes in experimental leishmania amazonensis infection: comparison between immunized and naive balb/c mice. | highly susceptible naive balb/c mice or mice that had previously been immunized i.v. with solubilized homologous antigen (partially resistant) were infected with leishmania amazonensis. histologically, the main differences between the two groups were lymphocytic infiltration and macrophage activation. assays of t-cell function at 3 and 10 weeks after infection revealed that purified t-cells did not proliferate following treatment with leishmania antigen. a mitogenic anti-cd3 monoclonal antibody ... | 1992 | 1584741 |
| macrophage activation for intracellular killing as induced by a ca2+ ionophore. dependence on l-arginine-derived nitrogen oxidation products. | mouse macrophages activated by interferon-gamma kill intracellular leishmania by a process that depends on the generation of l-arginine-derived nitrogen oxidation products. interferon-induced intracellular killing can be mimicked by exposure of macrophages to the ca2+ ionophore a23187 in the presence of lipopolysaccharide. the mechanisms of this effect were therefore investigated. destruction of the parasite was accompanied by accumulation of nitrite in the macrophage culture fluids. leishmanici ... | 1992 | 1599422 |
| identification of a band 3-like protein in leishmania mexicana promastigotes. | 1992 | 1644062 | |
| surface ige and phagocytic activity of eosinophils from patients with american cutaneous leishmaniasis: relation to cell density. | eosinophils were isolated from the blood of american cutaneous leishmaniasis (acl) patients and healthy controls from the same endemic rural area (era) or from a non-endemic urban area (ua). for the purification of eosinophils a percoll discontinuous gradient method was used. we obtained a good cell viability (between 90 to 95%) and the more pure layers, which were the densest, ranged from 85 to 95% eosinophils. a high proportion of the acl patients and individuals from the era, had eosinophils ... | 1991 | 1669585 |
| leishmania donovani chagasi: new clinical variant of cutaneous leishmaniasis in honduras. | during surveillance for endemic visceral leishmaniasis on an island off the pacific coast of honduras, an unusual form of cutaneous leishmaniasis was encountered. by clinical and laboratory criteria, 17 cases were identified over 5 months; children aged 4 to 15 years were primarily affected. lesions were generally few in number, small, always papular, and non-ulcerative, even when present for several years. patients with skin lesions seemed otherwise healthy and were well nourished. montenegro s ... | 1991 | 1670724 |
| andean leishmaniasis in ecuador caused by infection with leishmania mexicana and l. major-like parasites. | between 1986 and 1988, epidemiologic studies were carried out in a small rural community in an andean region of ecuador, where cutaneous leishmaniasis is highly endemic. a total of 25 human cases, positive for leishmania parasites by culture and/or smear, were examined. fourteen of the cases were in infants less than one year of age, suggesting intradomiciliary transmission of the disease. clinically, many of these cases were similar to descriptions of "uta," a form of cutaneous leishmaniasis wh ... | 1991 | 1672799 |
| characteristics of multidrug resistance in plasmodium and leishmania: detection of p-glycoprotein-like components. | multidrug-resistance (mdr) in neoplastic cells is frequently characterized by the overexpression of p-glycoprotein (pgp), a 170 kda transmembrane glycoprotein that binds multiple cytotoxic drugs as well as calcium channel antagonists. chloroquine resistance in plasmodium falciparum appears to be analogous to mdr in neoplastic cells, where the induction of resistance with one drug confers resistance to other structurally and functionally unrelated drugs. to test the hypothesis that chloroquine re ... | 1991 | 1678253 |
| differentiation and limited proliferation of isolated leishmania mexicana amastigotes at 27 degrees c. | we have demonstrated here that while many amastigotes of both leishmania mexicana amazonensis and leishmania mexicana mexicana differentiate to promastigotes when placed in culture at 27 degrees c, many others remain as amastigotes in their proliferative cycle. we have used this system to examine the effects of the anti-leishmanial compounds amphotericin b, 4-pentenoate and sodium stibogluconate (pentostam) on the proliferation and differentiation of isolated extracellular amastigotes. amphoteri ... | 1991 | 1685870 |
| a galactosyl(alpha 1-3)mannose epitope on phospholipids of leishmania mexicana and l. braziliensis is recognized by trypanosomatid-infected human sera. | an immunoglobulin m antibody reactive with galactosyl(alpha 1-3)mannose [gal(alpha 1-3)man] residues present on phospholipids extracted from leishmania mexicana and l. braziliensis was found to be present in high titer in the serum of every normal individual studied. periodate oxidation, acid hydrolysis, or acetylation suppressed immunoreactivity, suggesting that an oligosaccharide chain was responsible for antibody binding. interaction occurs only with alpha-gal terminal residues, since treatme ... | 1990 | 1696285 |
| analyses of surface membrane carbohydrates in parasitic flagellates of the order kinetoplastida using lectins. | crithidia fasciculata, leishmania donovani, leishmania major, leishmania mexicana amazonensis, leishmania tropica, leishmania tarentolae, trypanosoma sp. from formosan bats (tb), trypanosoma lewisi, trypanosoma musculi, and different strains of trypanosoma cruzi (tc) were cultivated at 27 degrees c in a liquid culture medium. flagellates harvested from log phase culture were analyzed for their lectin agglutinating characteristics with concanavalin a (con a), peanut agglutinin, ricinus communis a ... | 1990 | 1696387 |
| antigenic variation in leishmania mexicana following infection of immunized mice leads to relative sparing of suppressor determinants. | intravenous immunization of balb/c mice with irradiated leishmania mexicana slows the growth of a subsequent intradermal inoculation of virulent parasites. prior subcutaneous immunization with irradiated parasites before i.v. immunization blocks the protective effect of the latter. parasites harvested from vaccinated mice grow more slowly in naive mice than the initial inoculated clone, and have a diminished capacity to immunize mice against this initial clone when used as (irradiated) i.v. immu ... | 1990 | 1696562 |
| effect of rna secondary structure and modified bases on the inhibition of trypanosomatid protein synthesis in cell free extracts by antisense oligodeoxynucleotides. | every messenger rna from leishmanias and trypanosomes has at its 5' end a conserved region termed the mini-exon sequence which, however, varies from species to species. in a systematic study mrnas from trypanosoma brucei, trypanosoma vivax, and leishmania enriettii were translated in cell-free extracts in the presence of oligodeoxynucleotides complementary to part of the mini-exon sequence. the affinity of the same oligonucleotides for target and non-target mrnas was determined by thermal elutio ... | 1990 | 1697674 |
| structural isoforms of a membrane transport protein from leishmania enriettii. | a membrane transport protein of the glucose transporter superfamily from leishmania enriettii is encoded by a family of tandemly repeated genes. the first gene in this tandem repeat codes for a structural isoform that contains a unique amino-terminal hydrophilic domain, probably located in the cytoplasm; the remainder of the protein is identical to the polypeptide encoded by the internal genes in the tandem repeat. the unique isoform is represented by a distinct stable rna. | 1990 | 1701025 |
| the surface free energy of leishmania mexicana amazonensis. | surface charge of leishmania mexicana amazonensis was investigated by direct zeta-potential determination and ultrastructural cytochemistry, and its surface tension was studied by measurements of the advancing contact angle formed by the parasite monolayers with drops of liquids of different polarities. both virulent and avirulent promastigotes exhibited negatively charged surfaces with a zeta-potential of about -15 mv. treatment of these cells with trypsin, alkaline phosphatase, or phospholipas ... | 1990 | 1705480 |
| biochemical characterization of the protective membrane glycoprotein gp46/m-2 of leishmania amazonensis. | biochemical features of the immunologically protective, membrane glycoprotein gp46/m-2 of leishmania amazonensis have been investigated. the protein appears to have a single carbohydrate side chain of approximately 3 kda, representing 7% of the mass of the mature gp46/m-2 protein. experiments removing this carbohydrate side chain from gp46/m-2 indicate that the carbohydrate is not involved in the epitope recognized by the monoclonal antibody, m-2. as this monoclonal antibody recognizes a species ... | 1991 | 1719417 |
| monoclonal antibodies to leishmania mexicana promastigote antigens. i. secreted acid phosphatase and other proteins share epitopes with lipophosphoglycan. | the abundant surface glycolipid, lipophosphoglycan (lpg), of leishmania promastigotes is composed of phosphosaccharide repeating units linked via a phosphosaccharide core to a conserved lyso alkylphosphatidylinositol membrane anchor. it is shown in this paper that monoclonal antibodies (mabs) directed against lpg also react with an acid phosphatase secreted by l. mexicana promastigotes. acid phosphatase purified by column chromatography (apparent mr = 100,000) reacts in immunoblots with the anti ... | 1991 | 1721919 |
| determination of phagocytosis of leishmania spp. by human polymorphonuclear leukocytes using anti-leishmania monoclonal antibodies. | phagocytosis of leishmania is an early event in the capacity of human polymorphonuclear cells to limit the spread of this infectious agent. we compared two methods to assess the phagocytosis of leishmania by pmn cells; the first using histochemical staining with wright or giemsa, and the second using the immunoperoxidase technique with anti-leishmania monoclonal antibodies. the quantitative results obtained with either of the cytochemical methods were comparable with the immunoperoxidase techniq ... | 1991 | 1727010 |
| leishmania amazonensis infection: a comparison of in vivo leishmanicidal mechanisms between immunized and naive infected balb/c mice. | in vitro studies have shown that both macrophage activation and destruction of parasitized macrophages lead to leishmania destruction. the relative role played by such mechanisms in vivo have not been properly evaluated. we took advantage of the model of intravenous immunization with solubilized leishmanial antigen which renders partially resistant the otherwise highly susceptible balb/c mice to address this issue avoiding the interference of different genetic backgrounds. leishmania destruction ... | 1992 | 1740178 |
| dna recombination associated with short direct repeats in leishmania mexicana m379. | 1992 | 1741022 | |
| monoclonal antibodies to leishmania mexicana promastigote antigens. ii. cellular localization of antigens in promastigotes and infected macrophages. | in the accompanying paper by ilg et al., it was shown that leishmania mexicana promastigotes covalently modify a secreted acid phosphatase and other proteins by carbohydrate epitopes characteristic for lipophosphoglycan (lpg). in this study, the reaction of the anti-lpg monoclonal antibodies (mabs ap3 and l7.25) and of mab l3.13, an antibody directed against an epitope present on the secreted acid phosphatase but not on lpg, with promastigotes and infected peritoneal macrophages is studied by im ... | 1991 | 1757501 |
| monthly variation in natural infection of the sandfly lutzomyia ayacuchensis with leishmania mexicana in an endemic focus in the ecuadorian andes. | in order to collect information on the role of lutzomyia ayacuchensis in the transmission of leishmaniasis in a newly discovered andean endemic focus in ecuador, a longitudinal field study was carried out over 13 months. monthly dissections were made of a minimum of 200 anthropophilic sandflies, collected at night during the month. a total of 2600 flies was separated from a small number of lu. osornoi, another anthropophilic species in the area, and dissected; 95 (3.65%) were naturally infected ... | 1991 | 1796881 |
| cutaneous leishmaniasis due to leishmania (leishmania) amazonensis in amazonian brazil, and the significance of a negative montenegro skin-test in human infections. | the clinical and epidemiological features of 62 cases of cutaneous leishmaniasis due to leishmania (leishmania) amazonensis, from pará state, amazonian brazil, are discussed. the parasite, isolated in hamster skin and/or blood-agar culture medium, was in each case identified by both biological characteristics and a monoclonal antibody specific for promastigotes of l. (l.) amazonensis. of the 62 patients, 46 (74.2%) presented with a single cutaneous lesion, and on no occasion was evidence found i ... | 1991 | 1801340 |
| partial purification and characterization of a beta-like dna polymerase from leishmania mexicana. | deoxyribonucleic acid polymerase beta (ec 2.7.7.7) from the lower eukaryotic parasitic protozoan leishmania mexicana has been partially purified over 9,000 fold and characterized for the very first time. like mammalian dna polymerase beta the protozoan enzyme is of low molecular weight (40,000), has a broad ph range, and is resistant to inhibition by n-ethylmaleimide and aphidicolin. it is unlike mammalian dna polymerase beta in utilization of various templates and response to various inhibitors ... | 1991 | 1805794 |
| variations in susceptibility to leishmania amazonensis infection in lines of mice selected for high or low immunoresponsiveness. | the degree of resistance to a local leishmania amazonensis challenge has been compared in lines of mice obtained by selective breeding for high or low immunoresponsiveness: high and low antibody responder mice of selections i and ii (hi, hii and li, lii lines) and high and low responder mice to t mitogen pha (hi/pha and lo/pha). the aim of this preliminary study was to focus attention on genetic differences related with well defined immune characteristics. clear-cut results were obtained, both h ... | 1991 | 1811215 |
| [diurnal biting activity and seasonal density of lutzomyia (c) orestes (diptera: psychodidae)]. | daily bite activity and season density of lutzomyia (c) orestes were recorded by means of the human bait technique in the don martin cave, west of havana province, during one year. a correlation matrix test was carried out between density, temperature, relative humidity and rainfall. | 1991 | 1812537 |
| [canine visceral leishmaniasis: evaluation of the serologic method used in epidemiologic studies]. | a comparative study was made of eluates of the blood of dogs experimentally infected with different trypanosomatids. using antigens prepared from promastigotes of leishmania mexicana, l. braziliensis and l. chagasi, assessments were made by the indirect immunofluorescence test. the results showed a sensitivity of 87.5% in the diagnosis of canine visceral leishmaniasis, independent of antigen used. cross-reactions occurred in 75% of cases of cutaneous leishmaniasis and 83.3% of dogs with chagas' ... | 1991 | 1815283 |
| conservation of cation-transporting atpase genes in leishmania. | dna fragments isolated from leishmania donovani atpase genes were used to analyze the organization and expression of cation transporting atpase genes in l. donovani, leishmania tropica, leishmania mexicana, leishmania braziliensis, trypanosoma brucei and trypanosoma cruzi. the atpase loci in all leishmania species contained a tandem pair of atpase genes arranged in head-to-tail orientation and separated by approximately 2 kb. no restriction site polymorphisms were detected in the internal portio ... | 1991 | 1828863 |
| characterization of a glycosylphosphatidylinositol membrane protein anchor precursor in leishmania mexicana. | 1991 | 1837068 | |
| [metacyclics of leishmania mexicana in the hypopharynx of lutzomyia youngi experimentally infected]. | although it has been postulated that the natural transmission of leishmaniasis occurs by regurgitation of the parasites from contaminated proboscis of phlebotomine vector recent experimental results seems to oppose this thesis. wild-caught and laboratory-reared females of lutzomyia youngi, vector of leishmania mexicana in the venezuelan andes, were infected on tarsal lesion of hamsters, inoculated 6 weeks previously s.c. with 2 x 10(4) amastigotes of l. mexicana s.l., isolated from venezuelan ca ... | 1991 | 1841249 |
| [production of monoclonal antibodies against leishmania mexicana mexicana antigens]. | in the present work we obtained three mabs specific against gp65 of the strain l. mexicana mexicana (nr). these three mabs were able of recognizing promastigotes of l.m.m. not only for immunofluorescence but also by immunostain. in the immunohistochemistry of biopsies of patients with leishmaniasis, using the three mabs, it was possible to observe the presence of amastigotes in the infected tissues. | 1991 | 1843566 |
| serum fibronectin promotes the leishmania interaction with neutrophils and macrophages. | 1991 | 1845240 | |
| chromosome rearrangement in leishmania mexicana m379. | circular extrachromosomal elements were observed in a variety of leishmania species. we show here that two lines originating from the same isolate have been found to contain a circular dna molecule of 26.6 kb and a linear chromosome of about 250 kb, respectively, which share a homology of more than 20 kb. the circular dna molecule and its related region on the linear chromosome were cloned and their restriction maps compared. this investigation reveals information about chromosome rearrangement ... | 1991 | 1852176 |