Publications

use of urine samples from healthy humans, nephritis patients or other animals as an alternative to foetal calf serum in the culture of leishmania (l.) donovani in vitro.	the effect of supplementing in-vitro cultures of leishmania donovani with urine was investigated. the parasites were isolated from bangladeshi patients with visceral leishmaniasis. the urine samples used were collected from healthy human donors, patients with nephrotic syndrome, diabetic nephritis (dn) or diabetes mellitus, a dog and a cow. promastigotes from blood-agar cultures were inoculated into rpmi-1640 basal medium with 10% heat-inactivated foetal calf serum (fcs) and/or 1%-20% urine. the ...	1999	10707106
kala-azar in a high transmission focus: an ethnic and geographic dimension.	in 1994-1996, we studied a group of 58 game wardens stationed in an area known to be highly endemic for visceral leishmaniasis (kala-azar) for evidence of infection with leishmania donovani. leishmania dna was detected by the polymerase chain reaction in the peripheral blood of cases of active kala-azar, former patients with visceral leishmaniasis, patients, and asymptomatic subjects. using the cloned antigen rk39, antibodies were detected in 44.2% of the game wardens while leishmanin skin test ...	1999	10674674
epidemiologic aspects of american visceral leishmaniasis in an endemic focus in eastern venezuela.	an endemic focus of american visceral leishmaniasis (avl) in eastern venezuela has been evaluated in terms of patients (n = 48), immunologic reactivity to leishmania in household contacts (n = 187) and neighborhood controls (n = 170), detection of leishmania (l. donovani complex) in dogs and wild animals by the polymerase chain reaction (pcr) and characteristics of the sandfly population. the male:female ratio of patients was 1.18:1; 89.6% were < or =12 years old. serologic reactivity was signif ...	1999	10674675
targeting of piperine intercalated in mannose-coated liposomes in experimental leishmaniasis.	the leishmanicidal property of piperine intercalated in liposomes and in mannose-coated liposomes was tested in experimental visceral leishmaniasis in hamsters. mannose-coated liposomal piperine eliminated intracellular amastigotes of leishmania donovani in splenic macrophages much more efficiently than did the liposomal piperine or free piperine. at a dose equivalent to 6 mg/kg body wt every 4th day for a total of 4 doses in 12 days, the mannose-coated liposomal piperine was found to reduce spl ...	1999	10650726
leishmania donovani parasites interact with gamma/delta+ human peripheral blood t cells and induce susceptibility to nk cell-mediated lysis.	we recently reported that leishmania donovani infect the human t-cell line in vitro. to examine whether primary human t cells could be infected by this parasite, a direct interaction of the peripheral blood t cells with l. donovani was examined. the percentage of gamma/delta+ t cells was markedly increased when in vitro generated normal human t-cell blasts were cultured with l. donovani amastigotes. about 30% of the gamma/delta+ t cells in the parasite exposed t-cell blasts expressed parasite an ...	1999	10636768
immunopathology of post kala-azar dermal leishmaniasis (pkdl): t-cell phenotypes and cytokine profile.	in sudan, post kala-azar dermal leishmaniasis (pkdl) caused by leishmania donovani develops in half of the patients treated for visceral leishmaniasis (kala-azar). in most patients lesions heal spontaneously, but in others symptoms are severe and persist for years. this study examined the immunological response in lesions of pkdl patients by immunohistochemistry and compared the findings with results obtained using peripheral blood mononuclear cells (pbmcs). in all lesions, parasites or parasite ...	1999	10629566
combined liposomal immuno- and chemotherapy of visceral leishmaniasis.	visceral leishmaniasis is a tropical disease caused by leishmania donovani, an obligate intracellular parasite. host cells of these parasites are macrophages. the conventional therapy of visceral leishmaniasis uses pentavalent antimony (pentostam). to minimize the undesired side effects of antimony and to possibly reduce the therapeutical dose of antimony it was combined with interferon gamma (ifn gamma) and encapsulated both in multilamellar vesicles for treatment of murine visceral leishmanias ...	1999	10604050
leishmania donovani invasion of the blood in a child with dermal leishmaniasis.	cutaneous leishmaniasis is highly endemic in eastern mediterranean countries. the causative organisms are leishmania tropica or leishmania major but, further west, variants of leishmania infantum frequently cause cutaneous leishmaniasis. we report a young girl from beirut with an acute cutaneous leishmaniasis in whom the causative organism was cultured from both the skin lesion and the blood in the absence of any signs or symptoms typical of systemic involvement. the parasite was found to have a ...	1999	10605522
leishmania major proteophosphoglycan is expressed by amastigotes and has an immunomodulatory effect on macrophage function.	proteophosphoglycan (ppg) is a newly described mucin-like glycoprotein found on the surface of leishmania major promastigotes and secreted in the culture supernatant. we show here that antigenically similar ppgs are present in several leishmania species. ppg could also be detected on the surface of amastigotes and in small, parasite-free vesicles in infected macrophages. because of the similarity of its carbohydrate chains to lipophosphoglycan, a parasite receptor for host macrophages, ppg was t ...	1999	10611735
stimulation of nonspecific resistance by thymopentin and its analogs against leishmania donovani infection in hamsters.	thymopentin and its analogs have been synthesized by the solution phase method of peptide synthesis and evaluated for their prophylactic efficacy against l. donovani infection in hamsters. thymopentin and some of the analogs were found to stimulate nonspecific resistance of the host against leishmania donovani infection in hamsters.	1999	10612455
glycoconjugates in leishmania infectivity.	leishmaniasis is a major health problem to humans and is caused by one of the world's major pathogens, the leishmania parasite. these protozoa have the remarkable ability to avoid destruction in hostile environments they encounter throughout their life cycle. that leishmania parasites have adapted to not only survive, but to proliferate largely is due to the protection conferred by unique glycoconjugates that are either on the parasites' cell surface or secreted. most of these specialized molecu ...	1999	10571023
the fatty acid and monosaccharide compositions of three neutral and three phosphorylated glycolipids isolated from leishmania donovani promastigotes grown in a chemically defined medium.	several lipids and macromolecular lipoconjugates of leishmania spp. have now been well characterized; however, the glycolipids of l. donovani have not been thoroughly examined. in the present study, 3 neutral and 3 phosphorylated glycolipids were detected in promastigote forms of the organism grown in a chemically defined medium. the fatty acid and sugar compositions of these glycolipids, isolated and purified by adsorption column chromatography and thin-layer chromatographic procedures, were id ...	1999	10577709
efficacy of the triazole sch 56592 against leishmania amazonensis and leishmania donovani in experimental murine cutaneous and visceral leishmaniases.	current therapy for leishmaniasis is unsatisfactory. efficacious and safe oral therapy would be ideal. we examined the efficacy of sch 56592, an investigational triazole antifungal agent, against cutaneous infection with leishmania amazonensis and visceral infection with leishmania donovani in balb/c mice. mice were infected in the ear pinna and tail with l. amazonensis promastigotes and were treated with oral sch 56592 or intraperitoneal amphotericin b for 21 days. at doses of 60 and 30 mg/kg/d ...	1999	10582881
diagnostic pcr with leishmania donovani specificity.		1999	10588774
the leishmania donovani ld1 locus gene orfg encodes a biopterin transporter (bt1).	we have previously described two genes, orff and orfg, from the ld1 locus near one telomere of chromosome 35, which are frequently amplified in leishmania isolates. in leishmania donovani lsb-51.1, gene conversion of the rrna gene locus on chromosome 27 with these two genes resulted in their over-expression, because of their transcription by the rna polymerase i-mediated rrna promoter. the predicted orfg protein has substantial sequence homology to the esag10 gene product from the trypanosoma br ...	1999	10589984
substrate depletion upregulates uptake of myo-inositol, glucose and adenosine in leishmania.	leishmania flagellates undergo a digenetic life cycle in the gut of the sandfly insect vector and in macrophage phagolysosomes of the mammalian host. this involves vast changes of the environment to which the parasite has to adapt, including temperature, ph and concentration of nutrients between different types of meals of the insect vector or within the enclosed intracellular environment of the phagolysosome. the regulation of transporters for important organic substrates in leishmania donovani ...	1999	10589986
evaluation of the in-vivo activity and toxicity of amarogentin, an antileishmanial agent, in both liposomal and niosomal forms.	the antileishmanial property of amarogentin, a secoiridoid glycoside isolated from the indian medicinal plant swertia chirata, was examined in a hamster model of experimental leishmaniasis. the therapeutic efficacy of amarogentin was evaluated in free and two different vesicular forms, liposomes and niosomes. the amarogentin in both liposomal and niosomal forms was found to be a more active leishmanicidal agent than the free amarogentin; and the niosomal form was found to be more efficacious tha ...	1999	10590280
dermatofibroma parasitized by leishmania in hiv infection: a new morphologic expression of dermal kala azar in an immunodepressed patient.	visceral leishmaniasis is a protozoan infection that may complicate the course of patients with human immunodeficiency virus (hiv). dermatofibroma is a cutaneous fibrohistiocytic lesion considered neoplastic by some authors and inflammatory by others. eruptive dermatofibromas have been described in patients with hiv infection or with other altered immunity situations. we present the case of a 32-year-old, hiv-positive man with visceral leishmaniasis who complained of the appearance of a cutaneou ...	1999	10599943
characterization of the glucosyltransferases that assemble the side chains of the indian leishmania donovani lipophosphoglycan.	the life cycle of leishmania parasites within its sand fly vector involves the development of extracellular promastigotes from a noninfective, "procyclic" stage into an infective, "metacyclic" stage that is adapted for transmission in the fly and survival in the mammalian host. lipophosphoglycan (lpg), the predominant surface glycoconjugate in both procyclic and metacyclic stages, is a critical virulence determinant. lpg is a multidomain molecule; the structural polymorphisms among species lie i ...	1999	10600177
leishmania donovani: characterization and expression of orff, a gene amplified from the ldi locus.	the ld1 locus is a 27.5-kb region of chromosome 35 that is conserved among all species of leishmania and is amplified in several different isolates. here, we report the genomic distribution of orff, a gene from the ld1 region, and its expression at the rna and protein levels in two indian isolates of leishmania donovani. in both of these isolates, orff was present as a single copy on chromosome 35. densitometric analysis of orff mrna abundance revealed relative abundance of 0.2 and 1.0 in ag83 a ...	1999	10600448
increased natural killer activity does not prevent progression of experimental kala-azar.	kala-azar is the visceral form of leishmaniasis and it is caused by intracellular parasites from the complex leishmania donovani. golden hamster (mesocricetus auratus) infected with leishmania donovani develop a disease very similar to human kala-azar. there is conspicuous hipergammaglobulinaemia and their t cells do not respond to stimulation with parasite antigens. we used this experimental model to evaluate the natural killer (nk) activity during the initial phase of the disease. outbred hams ...	1999	10564913
xanthine phosphoribosyltransferase from leishmania donovani. molecular cloning, biochemical characterization, and genetic analysis.	xanthine phosphoribosyltransferase (xprt) from leishmania donovani is a unique enzyme that lacks a mammalian counterpart and is, therefore, a potential target for antiparasitic therapy. to investigate the enzyme at the molecular and biochemical level, a cdna encoding the l. donovani xprt was isolated by functional complementation of a purine auxotroph of escherichia coli that also harbors deficiencies in the prokaryotic phosphoribosyltransferase (prt) activities. the cdna was then used to isolat ...	1999	10567419
differential decline in leishmania membrane antigen-specific immunoglobulin g (igg), igm, ige, and igg subclass antibodies in indian kala-azar patients after chemotherapy.	pathogenesis in kala-azar is associated with depressed cellular immunity and significant elevation of antileishmanial antibodies. since these antibodies are present even after cure, analysis of the parasite-specific isotypes and immunoglobulin g (igg) subclasses in kala-azar patients may shed new light on the immune responses during progression and resolution of infection. using leishmanial membrane antigenic extracts, we investigated the relative levels of specific igg, igm, iga, ige, and igg s ...	1999	10569788
the effect of buthionine sulfoximine on the growth of leishmania donovani in culture.	changes in composition of the principal low molecular mass thiols of leishmania donovani were monitored during the transformation of promastigotes, first to stationary phase metacyclic forms and then to amastigotes. no consistent variation in the thiol composition of the parasite which could account for the known increase in resistance of metacyclic and amastigote lifecycle forms to oxidant stress could be established. amastigotes cultivated at 37 degrees c also produced ovothiol a, as judged by ...	1999	10220890
indolylquinoline derivatives are cytotoxic to leishmania donovani promastigotes and amastigotes in vitro and are effective in treating murine visceral leishmaniasis.	a wide variety of biologically active compounds contain indole and quinoline nuclei. some novel indolylquinoline derivatives were synthesized from indole by friedel-crafts acylation reaction. out of the four derivatives tested, 2-(2''-acetamidobenzyl)-3-(3'-indolylquinoline) (c) had no effect on the promastigotes or amastigotes of leishmania donovani in vitro. the remaining three analogues, 2-(2''-dichloroacetamidobenzyl)-3-(3'-indolylquinoline) (a), 2-(2''-chloroacetamidobenzyl)-3-(3'-indolylqu ...	1999	10223591
[important parasitic nephropathies: update from the recent literature].	renal involvement in parasitic infections are polymorphic. plasmodium malariae often leads to membranoproliferative glomerulonephritis whereas acute tubular necrosis or post-infectious acute glomerulonephritis are observed with plasmodium falciparum. urogenital taxis of schistosoma haematobium is responsible for frequency of chronic tubular and interstitial nephritis. without specific treatment, the renal function progressively deteriorates and urological complications appear. schistosoma manson ...	1999	10227026
treatment of experimental leishmaniasis with the immunomodulators imiquimod and s-28463: efficacy and mode of action.	there is a need for new, effective, and less toxic treatments for leishmaniasis, an infectious disease caused by leishmania protozoa and is a major cause of suffering and morbidity in much of the developing world. imiquimod, an immune-response modifier, has recently been approved by the food and drug administration for the treatment of genital warts caused by human papillomaviruses. imiquimod initiates a local immune reaction, including the stimulation of macrophages, resulting in resolution of ...	1999	10228071
verification of differential gene transcription using virtual northern blotting.	we introduce here an alternative to conventional northern blotting that requires only minute amounts of rna. this has been achieved by modification of methods currently used for the mapping of mrna 5'-terminal ends. the terminal desoxynucleotidyl transferase-mediated g-tailing, cap finder, ligation-anchored and rna ligase-mediated approaches followed by polymerase chain reaction protocols all produced high quality cdnas in large amounts. these cdnas could be separated by electrophoresis to obtai ...	1999	10325436
synthesis and antileishmanial activity of alpha-cyano ethyl propenoates--a new class of antileishmanials.	a number of alpha-cyano-beta-substituted ethyl propenoates were synthesised by condensation of appropriate aldehydes with ethyl cyanoacetate in basic medium. these compounds have been studied for their antileishmanial activities in vivo in hamsters. two compounds exhibited 70-77% activities both by intramuscular and oral routes.	1999	10083984
visceral and cutaneous leishmaniasis (report of 2 cases).	leishmaniasis is an endemic, sporadic infection in many parts of the world. turkey is geographically unique in linking asia and europe. of special interest is leishmaniasis, as various forms of this disease have long been reported in the surrounding regions. visceral and cutaneous leishmaniasis are endemic in the western and southeastern parts of turkey, respectively. here, we report a cutaneous and a visceral leishmaniasis case, to draw attention to the increase in the incidence of leishmaniasi ...	1999	10084013
cytotoxicity of (2,2':6',2''-terpyridine)platinum(ii) complexes to leishmania donovani, trypanosoma cruzi, and trypanosoma brucei.	a range of (2,2':6',2''-terpyridine)platinum(ii) complexes are shown to possess antiprotozoal activity in vitro against leishmania donovani, trypanosoma cruzi, and trypanosoma brucei,the causative organisms of tropical diseases leishmaniasis and trypanosomiasis. the best compounds caused 100% and 78% inhibition of growth of the intracellular amastigote forms of l. donovani and t. cruzi, respectively, at a concentration of 1 microm and 100% inhibition of growth of the bloodstream trypomastigote f ...	1999	10090783
developmental regulation of proline transport in leishmania donovani.	leishmania donovani are the causative agents of kala azar in humans. these organisms cycle between the proline-rich environment of the sand fly vector (extracellular promastigotes) and the sugar-rich condition in the mammalian host (intracellular amastigotes). parasites have adapted to these extreme changes in proline concentrations: promastigotes utilize proline as a carbon source, whereas amastigotes utilize sugars and fatty acids. previous studies have suggested that promastigotes and amastig ...	1999	10092478
a perianal ulcer.		1999	10093983
folding stability of the kinetoplastid membrane protein-11 (kmp-11) from leishmania infantum.	kinetoplastid membrane protein-11 (kmp-11) is a major component of the cell surface of kinetoplastids, and acts as a potent b- and t-cell immunogen during leishmania infection. here we report that the leishmania infantum kmp-11 secondary structure adopts mainly an alpha-helical conformation at ph 7.5 and that its urea- and thermally-induced unfolding constitute a fully reversible two-step process. this allows estimation of a half-denaturation temperature of approximately 65 degrees c, a delta gd ...	1999	10095795
leishmania donovani infection of a susceptible host results in cd4+ t-cell apoptosis and decreased th1 cytokine production.	the disease visceral leishmaniasis is caused by a protozoan parasite, leishmania donovani and is characterized by depressed cell-mediated immunity (cmi) and unhindered parasite growth in a susceptible host. the opposite trend is observed in a resistant host. however, the mechanism of this loss of cmi during the progressive disease is unknown as yet. in this report, we demonstrate that more than 40% of cd4+ t cells from a susceptible host undergo apoptosis resulting in a significant decrease in i ...	1999	10102649
antiprotozoal activity of aporphine alkaloids isolated from unonopsis buchtienii (annonaceae).	on a preliminary screening, substantial leishmanicidal activity was observed for the petroleum ether and alkaloidal extracts of the stem bark of unonopsis buchtienii, the alkaloids and sterols isolated from these were studied. of the alkaloids, liriodenine exhibited the highest activity against leishmania major and l donovani (ic100 = 3.12 micrograms/ml). on the other hand, o-methylmoschatoline and the petroleum ether extract without alkaloids showed an interesting in vitro activity against tryp ...	1999	10190198
infectivity and attenuation of leishmania donovani promastigotes: association of galactosyl transferase with loss of parasite virulence.	during the course of long-term in vitro cultivation of leishmania donovani parasites, the promastigotes were found to lose their infectivity. lectin agglutination studies revealed that there is an up-regulation of terminally exposed galactose residues on the noninfective promastigotes. the enzyme galactosyl transferase was absent in the infective form but present in the non-infective form of the parasites. an association between galactosylation and loss of infectivity was also observed. we propo ...	1999	10207363
a dominant negative mutation in the gim1 gene of leishmania donovani is responsible for defects in glycosomal protein localization.	kinetoplastid protozoa contain a unique microbody organelle called the glycosome. several important metabolic pathways are compartmentalized within the glycosome that are found in the cytoplasm of higher eukaryotes. we have previously reported the identification of a leishmania donovani cell line called gim1-1, in which several normally glycosomal proteins are partially mislocalized to the cytoplasm. the gim1 gene complements the defect and restores import of proteins to the glycosome. here we d ...	1999	10215029
molecular cloning and expression of adenosine kinase from leishmania donovani: identification of unconventional p-loop motif.	the unique catalytic characteristics of adenosine kinase (adk) and its stage-specific differential activity pattern have made this enzyme a prospective target for chemotherapeutic manipulation in the purine-auxotrophic parasitic protozoan leishmania donovani. however, nothing is known about the structure of the parasite adk. we report here the cloning of its gene and the characterization of the gene product. the encoded protein, consisting of 345 amino acid residues with a calculated molecular m ...	1999	10215606
immune adherence-mediated opsonophagocytosis: the mechanism of leishmania infection.	to mimic the sandfly pool feeding process and characterize the cellular and biochemical events that occur during the early stages of promastigote-host interaction, we developed an ex vivo model of human blood infection with leishmania promastigotes. within 30 s of blood contact, leishmania promastigotes bind natural anti-leishmania antibodies, which then activate the classical complement pathway and opsonization by the third component of complement. the opsonized promastigotes undergo an immune ...	1999	9874561
the cured immune phenotype achieved by treatment of visceral leishmaniasis in the balb/c mouse with a nonionic surfactant vesicular formulation of sodium stibogluconate does not protect against reinfection.	single-dose treatment with sodium stibogluconate solution (ssg) and treatment with a nonionic surfactant vesicular formulation of sodium stibogluconate (ssg-niv) were compared for the ability to protect balb/c mice against infection with leishmania donovani. prophylactic treatment with ssg-niv protected against infection, although its effects were time and organ dependent; protection was not obtained with ssg. protection against reinfection with l. donovani was observed only in mice cured by tre ...	1999	9874665
isolation of a laminin-binding protein from the protozoan parasite leishmania donovani that may mediate cell adhesion.	extracellular matrix (ecm)-binding proteins on the surface of leishmania are thought to play a crucial role in the onset of leishmaniasis, as these parasites invade mononuclear phagocytes in various organs after migrating through the ecm. in a previous report, we presented several lines of evidence suggesting that leishmania has a specific receptor for laminin, a major ecm protein, with a kd in the nanomolar range. here we describe the identification, purification and biochemical characterizatio ...	1999	9895301
hemoglobin endocytosis in leishmania is mediated through a 46-kda protein located in the flagellar pocket.	four lines of evidence indicate that a specific high affinity binding site on the surface of leishmania donovani promastigotes mediates rapid internalization and degradation of hemoglobin. 1) binding and uptake of 125i-hemoglobin by leishmania followed saturation kinetics and were competed by unlabeled hemoglobin but not by globin or hemin or other heme- or iron-containing proteins. 2) immunogold labeling studies revealed that, at 4 degreesc, hemoglobin binding was localized in the flagellar poc ...	1999	9915807
leishmania: identification of old world species using a permissively primed intergenic polymorphic-polymerase chain reaction.	we have developed a permissively primed intergenic polymorphic-polymerase chain reaction (ppip-pcr) which distinguishes between the old world leishmania complexes l. major, l. tropica, l. donovani, and l. aethiopica. this technique pairs one parasite-specific and one nonspecific oligonucleotide primer for the pcr. the specific primer was chosen from a unique leishmanial dna sequence, clone pdog 2, isolated from a l. donovani chagasi genomic dna expression library. this sequence has a high dna ho ...	1999	9920044
ornithine decarboxylase gene deletion mutants of leishmania donovani.	a knockout strain of leishmania donovani lacking both ornithine decarboxylase (odc) alleles has been created by targeted gene replacement. growth of deltaodc cells in polyamine-deficient medium resulted in a rapid and profound depletion of cellular putrescine pools, although levels of spermidine were relatively unaffected. concentrations of trypanothione, a spermidine conjugate, were also reduced, whereas glutathione concentrations were augmented. the deltaodc l. donovani exhibited an auxotrophy ...	1999	9920931
stage-specific activity of pentavalent antimony against leishmania donovani axenic amastigotes.	the standard treatment of human visceral leishmaniasis involves the use of pentavalent antimony (sbv) compounds. in recent years increasing numbers of clinical failures of treatment with sbv have been reported, probably due to the development of parasite resistance to this compound. the mode of action and mechanisms of resistance to sbv have not been fully elucidated. in the present study an axenic amastigote culture was used to study the in vitro responses of leishmania donovani to sbv. suscept ...	1999	9925518
activity of a heat-induced reformulation of amphotericin b deoxycholate (fungizone) against leishmania donovani.	the heat treatment of amphotericin b deoxycholate (fungizone), which was previously shown to induce superaggregation and decrease the toxicity of the drug to mammalian cells, increased its activity against leishmania donovani in balb/c mice, whereas it reduced its toxicity. heat treatment preserved the activity of fungizone against l. donovani hu3-infected mouse peritoneal macrophages.	1999	9925541
leishmania donovani infection initiates t cell-independent chemokine responses, which are subsequently amplified in a t cell-dependent manner.	control of leishmania donovani infection in immunocompetent mice is associated with hepatic inflammation and granuloma formation, both of which are absent in severe combined immunodeficient (scid) mice. in both balb/c and scid mice, l. donovani infection induced a rapid hepatic accumulation of mrna encoding macrophage inflammatory protein-1alpha (mip-(1alpha), monocyte chemoattractant protein-1 (mcp-1) and interferon-gamma inducible protein-10 (gammaip-10). this response was not preceded by incr ...	1999	9933102
strain-specific recognition of live leishmania donovani promastigotes by homologous antiserum raised against a crude membrane fraction of infected macrophages.	surface antigens on leishmania promastigotes and infected macrophages are obvious targets in immunoprophylaxis for leishmanial infection. we have recently demonstrated that the polyclonal antiserum and monoclonal antibodies generated by homologous immunizations with the crude membranes of parasite-infected cells react effectively with the 'neo-antigenic' determinants on the infected cell surface. in the present study, we investigated the utility of such polyclonal antisera for identifying 'minor ...	1999	9950223
immunoprophylaxis and immunotherapy against experimental visceral leishmaniasis.	the ability of the leishmanial parasite, ur6 (mhom/in/1978/ur6) to act as a immunoprophylactic and immunotherapeutic agent against experimental visceral leishmaniasis in a hamster model was tested. the leishmanial parasite, ur6, lacked lpg but possessed abundant message for kinetoplastid membrane protein-11 (kmp-11), and failed to induce visceral infection when given through the intracardiac route, unlike the virulent leishmania donovani, ag83 (mhom/in/1983/ag83), the causative agent of kala-aza ...	1999	9987166
operational validation of the direct agglutination test for diagnosis of visceral leishmaniasis.	the validity of the direct agglutination test (dat) for visceral leishmaniasis (vl) was studied with a standardized field kit on 148 clinically suspected persons and 176 healthy controls recruited between 1993 and 1994 from an endemic area in gedaref state, sudan. a sensitivity of 95.9% and a specificity of 99.4% were found at a 1: 8,000 cut-off titer when parasitologically confirmed cases were compared with healthy controls. while corroborating previously reported sensitivity and specificity es ...	1999	9988336
macrophage microbicidal mechanisms in vivo: reactive nitrogen versus oxygen intermediates in the killing of intracellular visceral leishmania donovani.	to determine the relative contributions of respiratory burst-derived reactive oxygen intermediates (roi) versus reactive nitrogen intermediates (rni) to macrophage-mediated intracellular host defense, mice genetically deficient in these mechanisms were challenged with leishmania donovani, a protozoan that selectively parasitizes visceral tissue macrophages. during the early stage of liver infection at wk 2, both respiratory burst-deficient gp91(phox)-/- (x-linked chronic granulomatous disease [x ...	1999	9989990
kinetoplast dna minicircles of leishmania donovani express a protein product.	we describe an unprecedented finding of an open reading frame present in the variable region in one of the minicircle sequence classes of a human pathogenic strain of leishmania donovani (mhom/in/90/rmri 68) which is transcribed and translated. the encoded protein showed homologies to known transport proteins.	1999	10023079
purification, characterization, and drug susceptibility of tubulin from leishmania.	past work suggests that tubulin from kinetoplastid parasites may present an excellent drug target. to explore this possibility, tubulin was purified on a milligram scale from leishmania mexicana amazonensis promastigotes by sonication, deae-sepharose chromatography, and one cycle of assembly-disassembly. purified leishmanial tubulin is recognized by commercially available anti-tubulin antibodies and displays concentration dependent assembly in vitro. the vinca site agents vinblastine, maytansine ...	1999	10029309
developmental regulation of spliced leader rna gene in leishmania donovani amastigotes is mediated by specific polyadenylation.	leishmania cycles between the insect vector and its mammalian host undergoing several important changes mediated by the stage-specific expression of a number of genes. using a genomic differential screening approach, we isolated differentially expressed cosmid clones carrying several copies of the mini-exon gene. we report that the spliced leader (sl) rna, essential for the maturation of all pre-mrnas by trans-splicing, is developmentally regulated in leishmania donovani amastigotes and that thi ...	1999	10037755
therapeutic and prophylactic uses of protein a in the control of leishmania donovani infection in experimental animals.	the role of the immunomodulator protein a (pa) (from staphylococcus aureus, cowan i strain) in the control of leishmanial infection was studied in experimental animals. treatment of leishmania donovani infected hamsters with pa led to a moderate level of reduction of parasite load in their spleen (68%) and liver (46%). however, combination therapy of pa with the antileishmanial drug stibanate induced a more marked reduction of the spleen (88%) and liver (85%) parasitemia compared to that induced ...	1999	10065740
immunoglobulin subclass distribution and diagnostic value of leishmania donovani antigen-specific immunoglobulin g3 in indian kala-azar patients.	visceral leishmaniasis, or kala-azar, a fatal tropical disease, remains problematic, as early diagnosis is difficult and treatment often results in drug resistance and relapse. we have developed a sensitive enzyme-linked immunosorbent assay (elisa), using leishmanial membrane antigenic extracts (lag) to detect specific antibody responses in 25 untreated indian visceral leishmaniasis patients. to investigate the pathogenetic significance of isotype markers in kala-azar, relative levels of specifi ...	1999	10066659
analysis of the humoral immune response against total and recombinant antigens of leishmania infantum: correlation with disease progression in canine experimental leishmaniasis.	leishmaniasis by leishmania infantum in the mediterranean basin constitutes an important problem in both human and veterinary medicine. based in both the importance of canids as reservoirs for the human disease and the fact that the canine disease may be an excellent model for the human condition, the present work has been conducted to analyze clinical and immune mechanisms associated with canine experimental leishmaniasis. six-month-old mixed-breed dogs were intravenously infected with l. infan ...	1999	10077418
immunoblot analysis of the antibody response to antigens of leishmania donovani in indian kala-azar.	when infected with leishmania donovani, patients develop specific antibodies that constitute the basis of serodiagnosis. using immunoblot analysis, we examined the antibody response to antigens of l. donovani in 35 kala-azar (ka) patients and 67 controls. sera from ka patients recognised numerous antigens with molecular weights ranging from 14-110 kda. antigens of 40 kda, 55 kda, 65 kda, 70 kda and 82 kda were recognised most frequently. all ka patients produce an antibody response to one or mor ...	1999	10795370
kala azar.	although visceral leishmaniasis (vl) or kala-azar caused by leishmania donovani (ld) is globally, a public health problem and its eradication is of high priority, yet until now, no animal reservoir has been found in india and transmission of kala-azar occurs from man to man through the recognised vector p. argentipes. the cutaneous or dermal leishmaniasis is caused by l. tropica and this is restricted to rajasthan where it is zoonotic. investigation by sharma et al revealed the presence of zoono ...	1999	10798109
a new focus of visceral leishmaniasis in sub-himalayan (kumaon) region of northern india.	a localised focus of visceral leishmaniasis is reported for the first time from kumaon region of north india. during a period of 18 months from july 1997 to december 1998 several cases of pyrexia of unknown origin with unresponsiveness to antibiotics and anti-tubercular treatments were referred to the all india institute of medical sciences, new delhi. five of these were diagnosed to have visceral leishmaniasis. one of these was also co-infected with hiv-1. all the five cases came from an adjoin ...	1999	10810593
impaired recruitment of the small gtpase rab7 correlates with the inhibition of phagosome maturation by leishmania donovani promastigotes.	we have shown recently that one of the survival strategies used by leishmania donovani promastigotes during the establishment of infection in macrophages consists in inhibiting phagosome-endosome fusion. this inhibition requires the expression of lipophosphoglycan (lpg), the predominant surface glycoconjugate of promastigotes, as parasites expressing truncated forms of lpg reside in phagosomes that fuse extensively with endocytic organelles. in the present study, we developed a single-organelle ...	1999	11207538
cationic liposome-encapsulated antisense oligonucleotide mediates efficient killing of intracellular leishmania.	antisense oligonucleotides have been considered as inhibitors of growth of intracellular parasites such as leishmania, but only limited inhibition has been observed in vitro. we have encapsulated an antisense oligonucleotide, complementary to the leishmania universal miniexon sequence, in cationic liposomes. low concentrations (4 microm) of encapsulated oligonucleotides specifically reduced the amastigote burden within cultured macrophages by 80%. this result illustrates the importance of effect ...	1999	10333480
phosphoglycosylation of a secreted acid phosphatase from leishmania donovani.	the secreted acid phosphatase (sacp) of l.donovani is a heterogeneous glycoprotein that displays a wide array of n- and o-linked glycosylations. the o-linked sugars are of particular interest due to their similarity to the phosphoglycan structures of the major lipophosphoglycan surface antigen and released phosphoglycan (turco et al., 1987; greis et al., 1992). this study describes a structural analysis of the sacp o-linked glycosylations using mass spectroscopy, amino acid sequencing, and enzym ...	1999	10336996
clinical and laboratory study of kala-azar in children in nepal.	reports are scanty regarding kala-azar in children in nepal. in this communication we document 20 children diagnosed to have kala-azar who were admitted and treated at b. p. koirala institute of health sciences, dharan, nepal. the children were between 2 and 14 years old. the duration of illness varied between 12 days and 24 months with a majority (65 per cent) of children being ill for less than 6 months. hepatomegaly and splenomegaly were seen in 95 and 90 per cent of cases respectively. splen ...	1999	10341503
down-regulation of marcks-related protein (mrp) in macrophages infected with leishmania.	leishmania, a protozoan parasite of macrophages, has been shown to interfere with host cell signal transduction pathways including protein kinase c (pkc)-dependent signaling. myristoylated alanine-rich c kinase substrate (marcks) and marcks-related protein (mrp, macmarcks) are pkc substrates in diverse cell types. marcks and mrp are thought to regulate the actin network and thereby participate in cellular responses involving cytoskeletal rearrangement. because mrp is a major pkc substrate in mac ...	1999	10358020
presence of a vacuolar h+-pyrophosphatase in promastigotes of leishmania donovani and its localization to a different compartment from the vacuolar h+-atpase.	inorganic pyrophosphate promoted the acidification of an intracellular compartment in permeabilized promastigotes of leishmania donovani, as measured by acridine orange uptake. the proton gradient generated by pyrophosphate was collapsed by addition of nigericin or nh4cl. pyrophosphate-driven proton translocation was stimulated by potassium ions, and inhibited by naf, the pyrophosphate analogues imidodiphosphate and aminomethylenediphosphonate (amdp), dicyclohexylcarbodiimide, and the thiol reag ...	1999	10359662
leishmania-specific t cells expressing interferon-gamma (ifn-gamma) and il-10 upon activation are expanded in individuals cured of visceral leishmaniasis.	peripheral blood mononuclear cells (pbmc) from patients who have recovered from visceral leishmaniasis often respond to leishmania antigens in vitro by production of both il-4, ifn-gamma and il-10. in order to establish the cellular sources of these cytokines, we activated cells from individuals with a history of visceral leishmaniasis with leishmania antigen for 6 days in culture, and identified cytokine production at the single-cell level by flow cytometry. the cytokines were only found in cd3 ...	1999	10361241
in vitro leishmanicidal activity of aurones.	a series of aurones with drug-potential for leishmania infections was identified in vitro using both a direct cytotoxicity assay against extracellular promastigotes of leishmania donovani, l. infantum, l. enriettii, and l. major, and a test against intracellular amastigote forms of l. donovani residing within murine macrophages. the most active aurone (6-hydroxy-2-[phenylmethylene]-3(2h)-benzofuranone) had an ec50 of 0.45 microgram/ml in the extra-, and an ec50 of 1.40 micrograms/ml in the intra ...	1999	10364835
characterization of a leishmania donovani gene encoding a protein that closely resembles a type ib topoisomerase.	in order to clone the gene encoding a type i dna topoisomerase from leishmania donovani, a pcr-amplified dna fragment obtained with degenerate oligodeoxyribonucleotides was used to screen a genomic library from this parasite. an open reading frame of 1905 bases encoding a putative protein of 635 amino acid residues was isolated. a substantial part of the protein shares a significant degree of homology with the sequence of other known members of the ib topoisomerase family, in a highly conserved ...	1999	10373592
inhibition of succinyl coa synthetase histidine-phosphorylation in trypanosoma brucei by an inhibitor of bacterial two-component systems.	recent drug screenings for new antibacterial drugs directed against histidine phospho-relay signalling pathways in bacteria have resulted in compounds which potently inhibit the histidine kinase activity of bacterial two-component systems. the present study demonstrates that one of these compounds, ly266500, is also a potent inhibitor of histidine phosphorylation in the unicellular eukaryotic parasite trypanosoma brucei, both in vitro and in whole cells. in vitro, it inhibits histidine phosphory ...	1999	10376993
effect of acidic ph on heat shock gene expression in leishmania.	temperature and ph shifts trigger differential gene expression and stage transformation in leishmania. the parasites encounter dramatic fluctuations in the extra-cellular ph between the mid-gut of the sand fly (ph>8) and the phagolysosomal vacuole of mammalian macrophages (ph<6). the authors examined the effect of ph shifts on heat shock gene expression in leishmania amazonensis and leishmania donovani promastigotes. acidic ph resulted in preferential stability of the hsp83 transcripts at 26 deg ...	1999	10376997
leishmania donovani: cellular and humoral immune responses in indian langur monkeys, presbytis entellus.	we have previously reported that disease mimicking human visceral leishmaniasis can be established in presbytis entellus, the indian langur monkey, following a single intravenous challenge of 10(8) leishmania donovani amastigotes. in the present report, infection was assessed in monkeys infected intravenously with a single dose of 10(8) amastigotes (hda group), three weekly doses of 10(7) amastigotes (lda group) and three weekly doses of 5 x 10(7) promastigotes (hdp group). typical clinical infe ...	1999	10379815
experimental visceral leishmaniasis in high and low antibody-producer mice (selection iv-a).	leishmaniasis is a typical parasite infection whose protective immunity depends on macrophage activation. susceptibility to leishmania donovani infection was compared in h (high antibody responder) and l (low antibody responder) mice from selection iv-a. h mice infected intravenously with 10(7) amastigotes of l. donovani were more susceptible to infection than their l counterparts. this higher susceptibility was characterized by a higher splenic and hepatic parasite burden. an increased splenic ...	1999	10380560
lectin-binding properties of different leishmania species.	carbohydrate cell-surface residues on stationary promastigotes of 19 isolates of leishmania were studied with a panel of 27 highly purified lectins, which were specific for n-acetyl-d-glucosamine, d-mannose, l-fucose, d-galactose, n-acetyl-d-galactosamine, and sialic acid. the specificity of the cell-surface carbohydrates was analyzed by agglutination and radioiodinated lectin-binding assays. l. (l.) amazonensis and l. (l.) donovani were agglutinated by 12 and 10 of the 27 lectins used, respecti ...	1999	10382607
immunosuppression in hamsters with progressive visceral leishmaniasis: an evaluation of the role of nitric oxide toward impairment of the lymphoproliferative response.	the progressive visceral infection caused in golden hamsters by leishmania donovani amastigotes led to gradual impairment of the proliferative response of their splenic (spmc) or peripheral blood (pbmc) mononuclear cells to in vitro stimulation with leishmanial antigen, with mitogen (concanavalin a), and even with a combination of phorbol myristate acetate (pma) and ionomycin (io). removal of macrophage-like adherent cells from spmc or pbmc of infected animals, however, almost completely restore ...	1999	10382610
diagnostic and prognostic potential of a competitive enzyme-linked immunosorbent assay for leishmaniasis in india.	a leishmania donovani species-specific monoclonal antibody (monoclonal antibody d2) was evaluated for its diagnostic and prognostic potential by a competitive enzyme-linked immunosorbent assay (c-elisa) in sera from indian patients with visceral leishmaniasis (vl) and seven patients with post-kala-azar dermal leishmaniasis (pkdl). these results were compared with those obtained by microscopy with giemsa-stained tissue smears and a direct enzyme-linked immunosorbent assay (direct elisa) with crud ...	1999	10391861
crystal structures of adenine phosphoribosyltransferase from leishmania donovani.	the enzyme adenine phosphoribosyltransferase (aprt) functions to salvage adenine by converting it to adenosine-5-monophosphate (amp). aprt deficiency in humans is a well characterized inborn error of metabolism, and aprt may contribute to the indispensable nutritional role of purine salvage in protozoan parasites, all of which lack de novo purine biosynthesis. we determined crystal structures for aprt from leishmania donovani in complex with the substrate adenine, the product amp, and sulfate an ...	1999	10393170
h-2m molecules, like mhc class ii molecules, are targeted to parasitophorous vacuoles of leishmania-infected macrophages and internalized by amastigotes of l. amazonensis and l. mexicana.	in their amastigote stage, leishmania are obligatory intracellular parasites of mammalian macrophages, residing and multiplying within phagolysosomal compartments called parasitophorous vacuoles (pv). these organelles have properties similar to those described for the mhc class ii compartments of antigen-presenting cells, sites where peptide-class ii molecule complexes are formed before their expression at the cell surface. after infection with leishmania amazonensis or l. mexicana, endocytosis ...	1999	10393812
evidence that the high incidence of treatment failures in indian kala-azar is due to the emergence of antimony-resistant strains of leishmania donovani.	the possibility that the high frequency of treatment failures in indian kala-azar might be due to infection with antimony-resistant strains of leishmania donovani has not been experimentally addressed. l. donovani isolates were obtained from splenic aspiration smears of 24 patients in bihar, india, who either did not respond (15) or did respond (9) to 1 or more full courses of treatment with sodium antimony gluconate (sag). a strong correlation (p<.001) between clinical response and sag sensitiv ...	1999	10395884
leishmania: overexpression and comparative structural analysis of the stage-regulated meta 1 gene.	the meta 1 gene of leishmania major is upregulated in metacyclic promastigotes and encodes an 11.5-kda protein with no significant similarities to other proteins in the existing databases. in this paper, we characterize the homologous meta 1 genes in l. amazonensis and l. donovani. proteins encoded by this gene in all three species present a high degree of identity. the meta 1 gene cannot be replaced by gene targeting in l. major, suggesting an essential role for the protein, at least in promast ...	1999	10403759
the antileishmanial activity of novel oxygenated chalcones and their mechanism of action.	our previous studies have shown that licochalcone a, an oxygenated chalcone, has antileishmanial and antimalarial activities, and alters the ultrastructure and function of the mitochondria of leishmania spp. parasites. the present study was designed to investigate the antileishmanial activity and the mechanism of action of a group of new oxygenated chalcones. the tested oxygenated chalcones inhibited the in-vitro growth of leishmania major promastigotes and leishmania donovani amastigotes. treat ...	1999	10404318
ca2+ and calmodulin-dependent protein phosphatase from leishmania donovani.	a protein phosphatase exclusively dependent upon micromolar amounts of ca2+ and calmodulin has been identified and partially purified from leishmania spp. complete obliteration of its activity is observed in the presence of calmodulin antagonists such as trifluoperazine, fluphenazine and calmidazolium. relative insensitivity to okadaic acid and lack of activation in the absence of ca2+ and calmodulin distinguishes this enzyme from pp1, pp2a and pp2c-type protein phosphatases. cross-reactivity of ...	1999	10406035
hypersensitivity reaction over lesions of post-kala-azar dermal leishmaniasis mimicking type 1 reaction in leprosy.		1999	10407631
relationship of membrane sidedness to the effects of the lipophosphoglycan of leishmania donovani on the fusion of influenza virus.	cells expressing the influenza hemagglutinin protein were fused to planar lipid bilayers containing the viral receptor gd1a at ph 5.0. an amphiphile known to alter membrane properties is lipophosphoglycan (lpg). this glycoconjugate was added from aqueous solution to either the cis or the trans monolayer to examine its effects on the fusion process. lpg markedly inhibited the formation of fusion pores when present in the cis monolayer but lpg in the trans monolayer had no effect on the parameters ...	1999	10411653
sequence homology within a minicircle class of the leishmania donovani complex.		1999	10413058
epidemiology of visceral leishmaniasis in india.	kala-azar has re-emerged from near eradication. the annual estimate for the incidence and prevalence of kala-azar cases worldwide is 0.5 million and 2.5 million, respectively. of these, 90% of the confirmed cases occur in india, nepal, bangladesh and sudan. in india, it is a serious problem in bihar, west bengal and eastern uttar pradesh where there is under-reporting of kala-azar and post kala-azar dermal leishmaniasis in women and children 0-9 years of age. untreated cases of kala-azar are ass ...	1999	10416321
activation of phosphotyrosine phosphatase activity attenuates mitogen-activated protein kinase signaling and inhibits c-fos and nitric oxide synthase expression in macrophages infected with leishmania donovani.	intracellular protozoan parasites of the genus leishmania antagonize host defense mechanisms by interfering with cell signaling in macrophages. in this report, the impact of leishmania donovani on mitogen-activated protein (map) kinases and nitric oxide synthase (nos) expression in the macrophage cell line raw 264 was investigated. overnight infection of cells with leishmania led to a significant decrease in phorbol-12-myristate-13-acetate (pma)-stimulated map kinase activity and inhibited pma-i ...	1999	10417174
vaccination of swiss albino mice against experimental visceral leishmaniasis with the fml antigen of leishmania donovani.	the fml antigen of leishmania donovani in combination with saponin, aluminum hydroxide (al(oh)3) and freund's incomplete adjuvant (fia) was used in vaccines tested in an outbred murine model of visceral leishmaniasis, either through intraperitoneal or subcutaneous routes. the humoral response was significantly higher in the groups treated with fml + saponin or fml + al(oh)3 than in controls, both before and after the infection. animals immunized by the i.p. route developed higher antibody titres ...	1999	10418902
effect of the microtubule stabilising agent taxol on leishmanial protozoan parasites in vitro.	taxol, a mitotic spindle toxin, was found to selectively inhibit the proliferation of leishmania donovani in vitro at nanomolar concentrations with an ic50 of 35 nm. concentrations of taxol as high as 50 nm, however, did not affect j774a.1 murine macrophages. taxol (30 nm) also inhibited amastigote multiplication within a j774a.1 macrophage cell line when used in a 10-day experiment. it resulted in the in vitro assembly of l. donovani microtubules in a dose-dependent manner. when promastigotes w ...	1999	10427726
isolation of a taxol-resistant leishmania donovani promastigote mutant that exhibits a multidrug-resistant phenotype.	we raised a strain of leishmania donovani in the laboratory that was resistant to 500 nm taxol. the ic50 of the wild-type strain for taxol was 35 nm and that of the taxol-resistant strain (t-500) was 1 microm. the t-500 strain exhibited a mdr phenotype; it was also resistant to other unrelated drugs like vinblastine, adriamycin and the commonly used antimonial drugs pentostam and glucantime. verapamil (20 nm), a calcium channel blocker, was found to reverse the resistance of t-500 to taxol. acqu ...	1999	10427727
intra-species and stage-specific polymorphisms in lipophosphoglycan structure control leishmania donovani-sand fly interactions.	the leishmania lipophosphoglycan conveys the ability for the parasites to avoid destruction in diverse host environments. during its life cycle within the sand fly vector, the parasite differentiates from a dividing procyclic promastigote stage that avoids expulsion from the midgut by attaching to the gut wall, to a nondividing metacyclic promastigote stage that is unable to attach to the midgut and migrates to the mouth parts for reinfection of a mammalian host. lipophosphoglycan plays an integ ...	1999	10433687
synergistic effect of interferon-gamma and mannosylated liposome-incorporated doxorubicin in the therapy of experimental visceral leishmaniasis.	active targeting of doxorubicin to macrophages was studied by incorporating it in mannose-coated liposomes by use of visceral leishmaniasis in balb/c mice as the model macrophage disease. mannosylated liposomal doxorubicin was more effective than liposomal doxorubicin or free doxorubicin. because leishmaniasis is accompanied by immunosuppression, immunostimulation by interferon (ifn)-gamma was evaluated to act synergistically with mannosylated liposomal doxorubicin therapy. combination chemother ...	1999	10438370
regulation and adaptation of glucose metabolism of the parasitic protist leishmania donovani at the enzyme and mrna levels.	adaptation of the glucose metabolism of leishmania donovani promastigotes (insect stage) was investigated by simultaneously measuring metabolic rates, enzyme activities, message levels, and cellular parameters under various conditions. chemostats were used to adapt cells to different growth rates with growth rate-limiting or excess glucose concentrations. l. donovani catabolized glucose to co(2), succinate, acetate, and pyruvate in ratios that depended on growth rate and glucose availability. ra ...	1999	10438756
antimicrobial, antitumor and antileishmania screening of medicinal plants from guinea-bissau.	following an ethnobotanical search carried out in guinea-bissau, eighteen extracts derived from sixteen medicinal species were screened for antimicrobial, antitumor and antileishmania activity. significant antitumor activity was found for holarrhena floribunda against kb (squamous carcinoma), sk-mel 28 (melanoma), a 549 (lung carcinoma) and mda-mb 231 (mamma carcinoma) cell lines, with corresponding ic50 values of 7.9, 9.0, 3.4 and 9.9 micrograms/ml. khaya senegalensis and anthostema senegalense ...	1999	10439484
diagnostic pcr with leishmania donovani specificity using sequences from the variable region of kinetoplast minicircle dna.	kala azar or visceral leishmaniasis, a parasitic disease caused by leishmania donovani, is presently causing an epidemic in the eastern region of india. diagnosis of kala azar is often complicated. we developed a pair of oligonucleotides suitable as primers from the variable region of a predominant sequence class of minicircles of l. donovani. these primers were used in a nonisotopic polymerase chain reaction and found to be highly specific for the parasites of l. donovani complex. using these p ...	1999	10444321
comparison of different staining procedures for the flow cytometric analysis of u-937 cells infected with different leishmania-species.	the human macrophage cell line u-937 infected with different leishmania species, leishmania mexicana amazonensis (lma), leishmania donovani (ld) and leishmania infantum (li), was analyzed by flow cytometry (fcm). leishmania spp. were labeled with different stains prior to the infection of the u-937 cells (bcecf-am, pkh2-gl and syto 17) or after the infection (ao, fitc-conjugated monoclonal antibodies, pi). infected cells were analyzed by flow cytometry, fluorescence microscopy and in parallel mi ...	1999	10445312
serodiagnosis of leishmania donovani infections: assessment of enzyme-linked immunosorbent assays using recombinant l. donovani gene b protein (gbp) and a peptide sequence of l. donovani gbp.	the repetitive sequence of leishmania major gene b protein (gbp) has previously been shown to be a useful tool in the diagnosis of cutaneous leishmaniasis (cl). here, we have assessed enzyme-linked immunosorbent assays (elisas) using recombinant l. donovani gbp (rgbp) and a peptide sequence of l. donovani gbp (gbpp) in the diagnosis of l. donovani infections in sudan. the sensitivity of the rgbp elisa in diagnosing visceral leishmaniasis (vl) and post kala-azar dermal leishmaniasis (pkdl) was 92 ...	1999	10450438
attenuation of mhc class ii expression in macrophages infected with mycobacterium bovis bacillus calmette-guérin involves class ii transactivator and depends on the nramp1 gene.	the natural resistance associated macrophage protein 1 (nramp1) gene determines the ability of murine macrophages to control infection with a group of intracellular pathogens, including salmonella typhimurium, leishmania donovani, and mycobacterium bovis bacillus calmette-guérin (bcg). the expression of the resistant allele of the nramp1 gene in murine macrophages is associated with a more efficient expression of several macrophage activation-associated genes, including class ii mhc loci. in thi ...	1999	10453010
possible role of the 34-kilodalton hyaluronic acid-binding protein in visceral leishmaniasis.	leishmania donovani, the causative organism of human visceral leishmaniasis, invades host macrophages through its interaction with the cell surface molecules of target cells. the presence of a cell surface protein (mr 34 kda) having specific affinity toward hyaluronan (ha), a major extracellular matrix component, has been previously reported in macrophage cell lines. in order to identify the possible role of this ha-binding protein (habp) in leishmaniasis, initially we demonstrated its overexpre ...	1999	10461949