| the potential of using recombinant dna species-specific probes for the identification of tropical leishmania. | | 1986 | 3012443 |
| growth of leishmania donovani amastigotes in the continuous human macrophage cell line u937: studies of drug efficacy and metabolism. | we have developed a simple and reproducible system for infecting a human macrophage cell line (u937) with stationary-phase leishmania donovani promastigotes. four days after infection, greater than 90% of the promastigotes had transformed to amastigotes. the antileishmanial agents allopurinol riboside, formycin b, 9-deazainosine, and sodium stibogluconate effectively inhibited the growth of l. donovani amastigotes in this cell line. to study the capability of amastigotes in the u937 cell line to ... | 1986 | 3014012 |
| identification of visceral leishmania species with cloned sequences of kinetoplast dna. | several efforts have been made in order to develop more precise and sensitive methods in the identification of leishmania parasites. we report here the identification of cloned subfragments of minicircle kinetoplast dna (kdna) isolated from l. donovani, wr352, which show different taxonomic specificities. analysis of these fragments demonstrates a significant sequence diversity within the kdna minicircle. for example, one cloned fragment was found to be present in all visceral leishmania species ... | 1986 | 3016536 |
| demonstration of various acid hydrolases and preliminary characterization of acid phosphatase in naegleria fowleri. | extracts of the pathogenic ameba naegleria fowleri, prepared by freeze-thawing and sonication, were analyzed for their content of various hydrolytic enzymes that have acid ph optima. the organism is rich in acid phosphatase activity as well as a variety of glycosidases which include beta-glucosidase, beta-galactosidase, beta-fucosidase, alpha-mannosidase, hexosaminidase, arylsulfatase a, and beta-glucuronidase. the crude extract contained only negligible levels of sphingomyelinase, neuraminidase ... | 1986 | 3018238 |
| hydrolysis of phosphoproteins and inositol phosphates by cell surface phosphatase of leishmania donovani. | leishmania donovani promastigotes contain intense tartrate-resistant cell surface acid phosphatase (acp1) which blocks superoxide anion production by activated human neutrophils [a.t. remaley et al. (1984) j. biol. chem, 259, 11173-11175]. an extensively purified preparation of acp1 dephosphorylates several phosphoproteins which are phosphorylated at serine residues; these include: pyruvate kinase (km 1.6 microm; vmax 71.4 u (mg protein)-1), phosphorylase kinase (km 0.076 microm; vmax 5.4 u (mg ... | 1986 | 3018559 |
| seroepidemiological study on kala-azar in baringo district, kenya. | this paper reports on 164 cases of kala-azar observed in the baringo district of kenya between february 1981 and february 1983. all were confirmed serologically by enzyme-linked immunosorbent assay (elisa) and all but 20 by parasitological examination as well. following the standard treatment with a 30 day course of sodium stibogluconate (pentostam) two non-responders and four relapses were observed. children between 2 and 15 years old were found to be the most affected age group; male patients ... | 1986 | 3021967 |
| purification and properties of cytochrome c555 from leishmania donovani. | a hemoprotein present in minute quantities in leishmania donovani promastigotes was isolated, purified and spectrally characterized as cytochrome c555. physicochemical characterization revealed electrophoretic mobility of 1.6 x 10(-5) cm2 v-1 s-1, an isoelectric point (pi) of 9.9, a relative molecular weight (mr) of 11.9 kda and half-wave potential (ep) of -1.058 v. values obtained were compared with those of horse heart cytochrome c subjected to the same analyses. heme c555 was also prepared an ... | 1986 | 3022142 |
| evolution of the genus leishmania as revealed by comparisons of nuclear dna restriction fragment patterns. | restriction endonuclease dna fragment patterns have been used to examine the relationships among 28 isolates of leishmania as well as crithidia, endotrypanum, and trypanosoma cruzi. fragments of nuclear dna were generated with six restriction enzymes, and blots were hybridized with probes from three loci. among the major lineages the fragment patterns are essentially completely different, while within the major lineages various degrees of divergence are found. molecular evolutionary trees were c ... | 1987 | 3025876 |
| a simple procedure for the preparation of pure kinetoplast dna network free of nuclear dna from the kinetoplast hemoflagellate leishmania donovani. | a simple, inexpensive procedure for preparing pure kinetoplast dna network from leishmania donovani is described. l. donovani promastigotes were lysed by incubating with pronase in presence of sodium dodecylsulfate. crude kinetoplast dna networks were obtained by centrifugation of the lysate through a 20% sucrose solution. the pellet containing kinetoplast dna was deproteinized by phenol extraction. contaminating nuclear dnas were removed by denaturation with alkali, neutralization, and addition ... | 1986 | 3026202 |
| a cyclic nucleotide-independent protein kinase in leishmania donovani. | leishmania donovani promastigotes labelled for 2 h with 32pi incorporated radioactivity into at least 21 different proteins, as determined by sds/polyacrylamide-gel electrophoresis. pulse-chase studies with 32pi demonstrated that the labelled proteins were in a dynamic state: some radiolabelled proteins rapidly disappeared and others appeared after the chase. the possibility of an ectokinase on the parasite was examined; incubation of intact parasites for 10 min at 25 degrees c in an osmotically ... | 1986 | 3030283 |
| isolation and characterization of adenosine kinase from leishmania donovani. | adenosine kinase (atp:adenosine 5'-phosphotransferase, ec 2.7.1.20) has been purified 3250-fold from leishmania donovani promastigotes using ion-exchange, gel filtration, and affinity chromatography techniques. both native and sodium dodecyl sulfate-gel electrophoresis of the enzyme revealed a single polypeptide of around 38,000 molecular weight. biophysical and biochemical analyses of the enzyme reveal unique characteristics different from those of adenosine kinases from other eukaryotic source ... | 1987 | 3032935 |
| detection of leishmania parasites by dna in situ hybridization with non-radioactive probes. | in situ hybridization techniques develop rapidly into diagnostic tools of considerable value for detection of viruses and bacteria. here we report the application of this technique for the detection of leishmania parasites. biotin-labelled total promastigote dna was hybridized to cultured leishmania parasites and to blood and impression smears of infected mice. in promastigotes kinetoplasts were strongly stained, nuclei somewhat more diffuse. in amastigotes both nuclear and kinetoplast dna hybri ... | 1987 | 3035535 |
| renaturation of leishmania donovani 3'-nucleotidase following sodium dodecyl sulfate-polyacrylamide gel electrophoresis. | 1. renaturation of a 3'-nucleotidase from the surface membrane of leishmania donovani promastigotes was achieved following polyacrylamide gel electrophoresis (page) in the presence of sodium dodecyl sulfate (sds). 2. enzyme activity was detected in situ in gels, following sds removal, by incubating the gels in reaction mixtures containing 3'-amp or 3'-ump as substrate followed by staining for the inorganic phosphate (pi) reaction product with malachite green-molybic acid solution. 3. conditions ... | 1987 | 3040331 |
| an endemic focus of visceral leishmaniasis in meshkin-shahr, east azerbaijan province, north-west part of iran and ifa serological survey of the disease in this area. | the incidence of visceral leishmaniasis has being increased in iran during the recent decade. since 1980, more than 200 cases have been diagnosed from east azerbaijan province, mostly, from meshkin-shahr area. it seems, that kala-azar has being endemic in this area for a long time. the majority (86%) of kala-azar cases were found among children up to 4 years. the sex incidence ratio of males/females was 1.27/1. in ifa serological survey, sero-positive rate in females was higher than males. howev ... | 1988 | 3046770 |
| [immunodiagnostic findings in patients with kala-azar]. | using three immunoreactions (complement-fixation reaction; enzyme immune test; indirect immunofluorescence), antibody formation was tested in 66 patients with kala-azar and 74 controls (blood donors; accident patients). moderately elevated and high antibody levels for each of three reactions were defined to provide diagnostic criteria. moderately high or high antibody concentrations against leishmania antigen were found in one of the three immunoreactions in 9 patients, in two of the three in 21 ... | 1988 | 3046895 |
| the biology and biochemistry of the glucose transporter. | | 1988 | 3048404 |
| specific serodiagnosis of canine leishmaniasis by indirect immunofluorescence, indirect hemagglutination, and counterimmunoelectrophoresis. | the increased prevalence of leishmaniasis in dogs in mediterranean countries has necessitated use of a reliable specific method of immunodiagnosis. research was carried out on 88 dogs, among which were 26 with severe clinical leishmaniasis (group a), 15 with mild signs of disease (group b), and 11 without signs of disease (group c); in addition, 15 were healthy (group d) and 21 were affected with various other diseases (group e). dogs of groups d and e were used as controls. infection was confir ... | 1988 | 3052194 |
| nucleoside uptake in trypanosoma cruzi: analysis of a mutant resistant to tubercidin. | nucleoside salvage pathways are vital to the parasitic protozoan trypanosoma cruzi, and have become important targets in the development of new chemotherapeutic agents against this organism. we produced a mutant t. cruzi clone with a defect in the uptake of the adenosine analogue tubercidin which allowed us to hypothesize that there are at least two distinct nucleoside transport pathways in this parasite. the mutant shows a marked defect in the uptake of tubercidin and thymidine, whereas the upt ... | 1988 | 3054542 |
| identification and characterization of a non-interferon antileishmanial macrophage activating factor (antileishmanial maf). | a non-interferon lymphokine elaborated from pha and con a-stimulated human t-cell hybridoma, t-cema, has been found to activate monocyte-derived macrophages for the intracellular killing of l. donovani (antileishmanial maf). this t-cell hybridoma derived antileishmanial maf which has an apparent mw of 65,000 and pi of 5.3-5.6, contains neither antiviral activity nor colony stimulating activity. furthermore, antileishmanial maf is not neutralized by anti-mif, anti-ifn-gamma or anti-gm-csf antibod ... | 1988 | 3059767 |
| [visceral kala-azar of spanish origin. apropos of a case]. | | 1988 | 3061269 |
| monoclonal antibodies that recognize distinct epitopes of the macrophage type three complement receptor differ in their ability to inhibit binding of leishmania promastigotes harvested at different phases of their growth cycle. | the macrophage receptor cr3 has been shown by several investigators to be involved in the binding of leishmania promastigotes to host macrophages. this receptor is known to recognize ic3b and to mediate direct lectin-like attachment of particles such as yeast zymosan. in the present study, two anti-cr3 monoclonal antibodies, m1/70 and 5c6, which ligate different epitopes of murine cr3, have been used in conjunction with sodium salicyl hydroxamate (saha; inhibits covalent ester linkages of c3 to ... | 1988 | 3065216 |
| [observations on kala azar in jacobina, bahia. vi. investigations on sylvatic and commensal mammals]. | | 1988 | 3068712 |
| a lymphokine distinct from interferon-gamma that activates human monocytes to kill leishmania donovani in vitro. | human interferon-gamma (ifn-gamma), a t cell lymphokine (lk), activates monocytes to kill many intra- and extracellular pathogens. in fact, previous reports assert that all activity in lk for macrophage activation is due to ifn-gamma. to test this assertion, we examined monocyte interactions with amastigotes of leishmania donovani after treatment with recombinant dna or affinity-purified leukocyte ifn-gamma and ifn-gamma containing lk. cells treated with at least 200 iu/ml ifn-gamma were microbi ... | 1986 | 3080522 |
| evaluation of the micro enzyme-linked immunosorbent assay (elisa) for antibodies in american visceral leishmaniasis: antigen selection for detection of infection-specific responses. | this study was designed to evaluate the elisa for diagnosis of american visceral leishmaniasis (avl) using antigen prepared from different leishmania isolates and from a strain of trypanosoma cruzi. two leishmania donovani chagasi isolates from bahia and maranhão (both states of northern brazil), one l. donovani from sudan, one l. mexicana amazonensis isolate, and one t. cruzi isolate were used. a total of 375 sera were tested, including 119 from avl patients, 96 from nonleishmaniasis hospitaliz ... | 1986 | 3080918 |
| [evolution of the interrelation of the linking members in the leishmania parasite system]. | | 1986 | 3086683 |
| analysis of trypanosoma cruzi antigens bound by specific antibodies and by antibodies to related trypanosomatids. | antigens of the epimastigote stage of trypanosoma cruzi were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions and examined for their ability to bind antibodies in sera from humans infected with this organism or infected with one or both of the related protozoa leishmania braziliensis and leishmania donovani by protein blot analysis and enzyme-linked immunosorbent assay. most of the antigens were bound by antibodies against each one of the organisms ... | 1986 | 3087879 |
| interaction and regulation of macrophage receptors. | macrophages express distinct plasma membrane receptors for different isotypes of immunoglobulin, bear at least two receptors for cleaved third complement component (cr1 and cr3) and have a lectin-like receptor that mediates endocytosis of glycoproteins or glycoconjugates with terminal mannose or fucose residues (mfr). interferon-gamma, a macrophage-activating factor, induces effects common to other interferons as well as having unique effects on cell function. the down-regulation of mfr, inducti ... | 1986 | 3089710 |
| 5'-methylthioadenosine (mta) phosphorylase from promastigotes of leishmania donovani. | | 1986 | 3094329 |
| effects of dl-alpha-difluoromethylornithine on leishmania donovani promastigotes. | alpha-difluoromethylornithine (dfmo), an irreversible inhibitor of ornithine decarboxylase, has been demonstrated to be an effective agent against a variety of parasitic protozoa but not against leishmania spp. in this report, we show that leishmania donovani promastigotes in continuous culture are sensitive to the growth inhibitory and cytotoxic effects of dfmo. incubation of the promastigotes with dfmo obliterates intracellular putrescine pools and depletes spermidine concentrations, which cor ... | 1986 | 3098971 |
| [preliminary results in favor of the existence of a major surface antigen, specific for leishmania braziliensis braziliensis]. | the comparative surface antigen study of 10 bolivian strains and 1 brazilian reference strain from l. b. braziliensis sub-species shows an important homogeneity within this group. all the strains tested so far present similar antigenic patterns with a major antigen at 72 kd. on the contrary, the comparative analysis of surface antigens of l. b. braziliensis with those of l. b. guyanensis, l. b. panamensis, l. mexicana amazonensis and l. donovani chagasi shows a large antigenic heterogeneity betw ... | 1986 | 3099979 |
| an analysis of t cell responsiveness in indian kala-azar. | the inability of most untreated patients with kala-azar to control their visceral infections with leishmania donovani has been attributed to a defective cell-mediated immune response to leishmanial antigens. we examined the in vitro response of t cells, including leu-2+-depleted t cell populations, to determine whether unresponsiveness could be reversed. these studies on patients with visceral leishmaniasis in bihar, north india, support previous observations regarding t cell unresponsiveness in ... | 1987 | 3100620 |
| experimental visceral leishmaniasis: production of interleukin 2 and interferon-gamma, tissue immune reaction, and response to treatment with interleukin 2 and interferon-gamma. | during the first 2 to 4 weeks of progressive visceral infection with the intracellular protozoan, leishmania donovani, spleen cells from balb/c mice failed in response to leishmanial antigen to produce either of the activating t cell-derived lymphokines, interleukin 2 (il 2) or gamma-interferon (ifn-gamma). four weeks after infection, however, antigen-induced il 2 and ifn-gamma secretion emerged and coincided with the onset of control over parasite replication and the subsequent killing of great ... | 1987 | 3104456 |
| in vitro and in vivo activation of human mononuclear phagocytes by interferon-gamma. studies with normal and aids monocytes. | to determine the potential immunotherapeutic role of interferon-gamma (ifn-gamma) as a mononuclear phagocyte-activating agent, we examined the effector cell function of peripheral blood monocytes from healthy donors and acquired immunodeficiency syndrome (aids) patients after either in vitro and/or in vivo treatment with recombinant (r) ifn-gamma. when assayed immediately after a 24-hr in vitro pulse with 300 u/ml, normal and aids monocytes behaved similarly with little augmentation of their int ... | 1987 | 3104467 |
| acquisition of cell-mediated immunity to leishmania. i. primary t-cell activation detected by il-2 receptor expression. | in order to analyse the early stages of the t-cell response to leishmania, bioassays for detecting low levels of il-2 receptor expression both in bulk culture and under limiting dilution conditions have been used. infection of c57bl/10 mice with leishmania donovani amastigotes leads to the appearance of antigen-specific t lymphocytes bearing high-affinity il-2 receptors 24-72 hr later. phenotypic analysis by complement-mediated cytotoxicity indicates that these activated t cells comprise both l3 ... | 1987 | 3111982 |
| response of inbred mice to aerosol challenge with mycobacterium tuberculosis. | an autosomal dominant gene (bcg), which maps to mouse chromosome 1, has been shown to confer on mice resistance to attenuated mycobacterium bovis bcg montreal, salmonella typhimurium, and leishmania donovani. most animal models used for the study of the bcg gene have involved intravenous injection of a large number of microorganisms (greater than 10(4) cfu). the present study examines the effect of the bcg gene on the resistance of inbred mice to challenge via the respiratory route with 5 to 10 ... | 1987 | 3112014 |
| a direct agglutination test discriminative toward chagas' disease for the diagnosis of visceral leishmaniasis in brazil: preliminary results. | two-hundred and sixty-five human sera from brazil were tested in a direct agglutination assay using trypsinated leishmania donovani donovani antigen. the assay proved to be of value for the diagnosis of american visceral leishmaniasis in that it was discriminative toward chagas' disease. | 1987 | 3115280 |
| leishmania donovani: generation of monospecific antibody reagents to soluble acid phosphatase. | four monoclonal antibodies (mcabs) were generated against the soluble extracellular acid phosphatase (ec 3.1.3.2) (s-acp) of leishmania donovani. these were detected in the primary screen using an elisa with promastigote culture supernatants as antigen. three of the mcabs demonstrated bound s-acp from such culture supernatants in an enzyme activity binding assay. all immunoprecipitated metabolically labeled s-acp but none showed any binding to the promastigote surface by indirect immunofluoresce ... | 1987 | 3115812 |
| recombinant human granulocyte/macrophage colony-stimulating factor activates intracellular killing of leishmania donovani by human monocyte-derived macrophages. | recombinant granulocyte/macrophage colony-stimulating factor (rgm-csf) obtained from cloned complementary mo cell dna and expressed in cos-1 cells activates cultured peripheral blood monocyte-derived macrophages in vitro to become cytotoxic for intracellular l. donovani. the antileishmanial effect of rgm-csf, which can be completely neutralized by anti-rgm-csf antiserum, is maximal after 36 h preincubation with the cultured macrophages, compared with that of rifn-gamma, which reaches its maximum ... | 1987 | 3119759 |
| identification and characterization of a ribose transport system in leishmania donovani promastigotes. | a transport system for ribose in leishmania donovani promastigotes was identified and characterized by measuring the uptake of radioisotope-labeled ribose. the pentoses arabinose, 2-deoxyribose and xylose inhibited ribose uptake, whereas hexoses (glucose, alpha-methylglucoside, thioglucose, galactose, lactose, maltose, mannose), adenosine, and proline did not inhibit uptake, indicating that the transporter exhibited substrate specificity. intracellular ribose exchanged with 2-deoxyribose. uptake ... | 1987 | 3123926 |
| dot-elisa using monoclonal antibodies for identification of leishmania donovani. | | 1987 | 3127137 |
| cross reactivity between trypanosoma cruzi and leishmania antigens in the lymphocyte blastogenesis assay. | the in vitro blastogenesis response of lymphocytes from 19 patients, with either visceral or mucocutaneous leishmaniasis or chagas disease, to antigens of the leishmania-trypanosoma complex was studied. cells from all patients responded to both homologous and heterologous antigens and the magnitude of the responses did not differ for any of the patient groups or antigens. | 1987 | 3127960 |
| immunofluorescence as an adjunct to the histopathologic diagnosis of chagas' disease. | we have developed a new indirect immunofluorescence procedure for identifying trypanosoma cruzi amastigotes in sections of formalin-fixed, paraffin-embedded tissue pretreated with a 0.25% trypsin solution to enhance immunofluorescence. in sections of human and mouse myocardia infected with t. cruzi and stained by this procedure, both intact amastigotes and phagocytosed amorphous antigen were intensely fluorescent and easily detected; nonspecific background fluorescence was absent or minimal. no ... | 1988 | 3128582 |
| role of l3t4+ and lyt-2+ cells in experimental visceral leishmaniasis. | in contrast to euthymic (nu/+) balb/c mice, athymic nude (nu/nu) balb/c mice fail to control the visceral intracellular replication of leishmania donovani, do not generate the macrophage-activating lymphokine ifn-gamma, and show little or no granulomatous tissue response. to characterize the t cell requirement for successful defense against l. donovani, nude mice were first reconstituted with unfractionated nu/+ immune spleen cells, which readily conferred the capacity to control and eliminate v ... | 1988 | 3131421 |
| survival of intracellular pathogens within human mononuclear phagocytes. | the preceding discussion makes it clear that there are multiple determinants, related to the microorganism, the host defense cell, and the presence of activating t cell stimuli that must be considered when examining at the cellular level how and why intracellular pathogens are able to cause infection. from the standpoint of the interaction of the mononuclear phagocyte's antimicrobial mechanisms with t gondii, l donovani, and c psittaci, the determinants which appear to influence directly the out ... | 1988 | 3133769 |
| analysis of lsh gene expression in congenic b10.l-lshr mice. | | 1988 | 3138075 |
| acquisition of cell-mediated immunity to leishmania. ii. lsh gene regulation of accessory cell function. | the macrophage natural resistance gene. lsh, regulates the ability of a selective population of tissue macrophages to control intracellular multiplication of leishmania donovani by a t-cell independent mechanism. we show here, using mice congenic for lsh, that this gene also contributes to the acquisition of t-cell-mediated immunity. whereas both resistant and susceptible mice generate equivalent primary t-cell responses to infection, resistant mice show a rapid increase in accessory cell activi ... | 1988 | 3141269 |
| kala-azar infected serum circulating antigens and their characteristics detected by monoclonal antibody. | | 1988 | 3142725 |
| leishmania donovani donovani antigens recognized by kala-azar patient sera and identification of cross-reacting antigens to chagas' disease. | l. donovani antigens were analyzed by a direct agglutination test (dat), by elisa using intact promastigotes and by the sds-page immunoperoxidase technique (sgip). sera of chagas' disease patients cross-reacted in the elisa and sgip but not in the dat. trypsin treatment of the parasites removed concanavalin a-binding sites but not epitopes for antibodies present in chagas' disease and in leishmaniasis sera, as seen in the sgip. eight bands were revealed after incubation of the gel sections with ... | 1988 | 3147797 |
| expression of the innate resistance gene ity in mouse kupffer cells infected with salmonella typhimurium in vitro. | early innate resistance to salmonellae in mice is controlled by the chromosome 1 gene ity which regulates the in vivo net growth rate of bacteria in the res by an unknown mechanism. it similarly controls innate resistance to leishmania donovani, bcg and mycobacterium lepraemurium. murine kupffer cell cultures were infected with virulent salmonella typhimurium and followed for 12 h. multiresistant organisms were used so that the antibiotics in the medium could not interfere with the results; extr ... | 1986 | 3150027 |
| prophylactic immunization against experimental leishmaniasis. v. mechanism of the anti-protective blocking effect induced by subcutaneous immunization against leishmania major infection. | the responsiveness of balb/c mice to protective i.v. immunization with 150,000-rad irradiated or heat-killed leishmania major promastigotes can be totally suppressed by prior subcutaneous (s.c.) injection of the same "vaccine." induction of this effect is leishmania specific for although prevention of protection against l. major infection can be obtained with either homologous or leishmania donovani promastigotes, it does not follow s.c. administration of an immunogenic trypanosoma cruzi epimast ... | 1985 | 3160786 |
| purification and characterization of an 80-kilodalton membrane protein from leishmania donovani. | visceral leishmaniasis is caused by the protozoan parasite leishmania donovani. we previously described the development of 16 monoclonal antibodies specific for l. donovani. the epitope recognized by one of these monoclonal antibodies, d13, is present at high density on nearly all isolates of l. donovani and, along with two other monoclonal antibodies, has been used to develop a sensitive and specific competitive assay for serodiagnosis of visceral leishmaniasis. in this report, we characterize ... | 1988 | 3165961 |
| [humoral response in leishmania infantum clinical infections]. | we sought a specific humoral response in man in order to find an antigenic marker of leishmania infantum infection. this study was carried out by the western blot technique; 42 sera from human patients were analysed on a standard electrophoretic pattern (sds-page) of l. infantum antigens. patient sera reacted specifically with 4 (160-, 140-, 94- and 79-kd) antigens, and reactive antibodies were igg. we suggest that these antigens may be used for diagnosis of l. infantum visceral leishmaniasis. | 1988 | 3166748 |
| acid phosphatase activity of virulent and avirulent clones of leishmania donovani promastigotes. | virulent and avirulent clones of leishmania donovani promastigotes were examined for their acid phosphatase activity. the acid phosphatase activity of whole-cell lysates of virulent clones was 1.5 to 2.0 times higher than that of avirulent clones. pellet fractions (260,000 x g, 30 min) from sonicated promastigotes of a virulent clone and an avirulent clone contained 60 and 40% of the total enzyme activity, respectively. membrane-bound acid phosphatase was extracted with triton x-100 from the pel ... | 1988 | 3169990 |
| ph homeostasis in leishmania donovani amastigotes and promastigotes. | intracellular ph and ph gradients of leishmania donovani amastigotes and promastigotes were determined over a broad range of extracellular ph values. intracellular ph was determined by 31p nmr and by equilibrium distribution studies with 5,5-dimethyloxazolidine-2,4-dione or methylamine. promastigotes maintain intracellular ph values close to neutral between extracellular ph values of 5.0 and 7.4. amastigote intracellular ph is maintained close to neutral at external ph values as low as 4.0. both ... | 1988 | 3174653 |
| visceral leishmaniasis in the sudan: comparative parasitological methods of diagnosis. | patients with suspected kala-azar had aspirations of spleen, lymph node and bone marrow performed to compare the relative merit of each procedure. splenic aspiration remains the method most likely to provide microscopic proof of leishmanial infection (18 of 19 samples) and was the only site positive in 5 patients. lymph node aspirates contained parasites in 20 of 29 patients, whereas bone marrow aspirates provided the diagnosis in 18 of 28. therefore, lymph node aspiration, with its minimal morb ... | 1988 | 3176153 |
| indigenous human cutaneous leishmaniasis caused by leishmania tropica in kenya. | six leishmania isolates from 3 indigenous kenyans (2 isolates from one patient) and 2 canadian visitors in kenya were characterized by cellulose acetate electrophoresis. the isolates were compared among themselves and with reference strains of leishmania donovani, l. aethiopica, l. major, l. tropica, and l. arabica using 9 enzymes: malate dehydrogenase (mdh), malic enzyme (me), phosphogluconate dehydrogenase (6pgd), glucose-6-phosphate dehydrogenase (g6pd), aspartate aminotransferase (asat), ade ... | 1988 | 3177740 |
| proposal for a function of the leishmania donovani lipophosphoglycan. | | 1988 | 3181610 |
| identification of leishmanial antigens in the sera of patients with american visceral leishmaniasis. | circulating immune complexes are present in the sera of patients with visceral leishmaniasis caused by leishmania donovani chagasi. in order to determine whether these complexes contain parasite antigens, sera were collected from brazilian patients with visceral leishmaniasis and from hospitalized control subjects with other diagnoses. high-molecular-weight complexes were precipitated from pooled sera with 2.5% polyethylene glycol. approximately 140-fold-more protein was precipitated from patien ... | 1988 | 3182074 |
| ribosome-inactivating proteins from plants inhibit ribosome activity of trypanosoma and leishmania. | ribosomes from trypanosoma brucei rhodesiense and from leishmania infantum were isolated and optimal conditions for in vitro translation were established. the effect of ribosome-inactivating proteins extracted from several plants was then assessed in order to identify those suitable for the preparation of immunotoxins against these organisms. ribosomes from both species were inactivated by some ribosome-inactivating proteins (dianthins, saporins, pokeweed antiviral proteins, and the ribosome-ina ... | 1988 | 3183997 |
| detection of leishmania donovani in live experimental hamsters. | | 1988 | 3188149 |
| an in vitro method for long-term maintenance of leishmania donovani chagasi. | | 1988 | 3188150 |
| acid phosphatase isoenzyme mapping in leishmania. | the profiles of acid phosphatase isoenzymes of several well defined species of the genus leishmania were compared. the profiles were generated after isoelectric focusing of parasite extracts in polyacrylamide and incubation of the gels with an appropriate substrate coupled to an azo dye. analysis of the zymograms showed that there is species-specificity of the acid phosphatase isoenzyme maps in leishmania. it was also demonstrated that different strains of the same species present identical patt ... | 1988 | 3191957 |
| in vivo killing of intracellular visceral leishmania donovani by a macrophage-targeted hydrogen peroxide-generating system. | | 1988 | 3198943 |
| comparison of the protein kinase and acid phosphatase activities of five species of leishmania. | promastigotes from log phase and stationary phase cultures of leishmania donovani, l. braziliensis panamensis, l. tropica, l. major, and l. mexicana amazonensis were analyzed for their content of protein kinase and acid phosphatase activities. cell surface, histone-specific protein kinase activity was 1.3- to 2.8-fold higher in stationary phase cells of all species except for l. tropica in which the activities of stationary and log phase cells were equal; l. mexicana amazonensis had the highest ... | 1988 | 3199342 |
| persistence of human leishmanial antibodies in an endemic area of visceral leishmaniasis in el agamy, egypt. | in an endemic area of visceral leishmaniasis (vl), individuals with leishmanial antibodies that reacted in the radioimmunoassay (ria) were retested to determine duration of leishmanial antibody retention. one fourth of adults retained antibodies for at least 10 months. at least 2/3 of asymptomatic children retained leishmanial antibodies for 5 to 7 months after detection. 2/3 of children treated for vl retained leishmanial antibodies for 5 to 7 months after treatment, while 1/3 retained antibodi ... | 1988 | 3203729 |
| heat shock and the relative hexokinase activity of leishmania aethiopica and leishmania donovani. | | 1988 | 3215177 |
| comparative study of the biological behaviour in hamster of two isolates of leishmania characterized respectively as l. major-like and l. donovani. | | 1988 | 3222614 |
| biotechnology and visceral leishmaniasis in the world health organization's southeast asian region: research and reality. | | 1988 | 3227396 |
| an enzyme-linked lectin assay for the study of lectin receptors of leishmania. | an enzyme-linked lectin assay (ella) based on the elisa assay, using intact formalin-fixed promastigotes to coat poly-l-lysine-treated microtiter plates is described. the assay was used to study the lectin receptors of leishmania donovani chagasi, l. donovani donovani and l. mexicana amazonensis. cona, rca, wga, and pna receptors were found in the three parasites. sba receptors were found to be as frequent as the other receptors in l. donovani chagasi but not in the other two parasites which sho ... | 1988 | 3228632 |
| a search for leishmania in normal skin and blood of kala-azar patients from bihar, india. | | 1988 | 3230291 |
| vaccination and treatment trials against murine leishmaniasis with semi-purified leishmania antigens. | antigens with molecular weight ranges of 94-67 kda (lif2), 30-20 kda (lif5), or below 20 kda (lif6), isolated from lysates of leishmania infantum promastigotes by electroelution from polyacrylamide gels were injected into mice which were genetically either partially resistant (c57bl/6) or susceptible (balb/c) to leishmania infection. one month after the completion of the intravenous (c57bl/6) or subcutaneous (balb/c) schedules, the mice were challenged with 1 x 10(3) l. major promastigotes. all ... | 1988 | 3232174 |
| isolation and typing of leishmania infantum from phlebotomus neglectus on the island of corfu, greece. | | 1988 | 3232178 |
| in vitro anti-leishmanial activity of compounds in current clinical use for unrelated diseases. | drugs in current clinical use were tested for anti-leishmania activity using an in vitro infected macrophage assay. out of almost 400 compounds tested, over 100 were active. the most active compounds showed ed50 values below 1 microm concentration. it is concluded that the active compounds should receive testing in the in vivo system. in addition they will act as lead compounds for further synthetic programmes. | 1988 | 3246207 |
| experimental infection of the opossum didelphis albiventris (marsupialia, didelphidae) with leishmania donovani. | | 1988 | 3249558 |
| isolation of leishmania donovani from phlebotomus martini in baringo district, kenya. | an 18-month sandfly survey was conducted at 4 locations in baringo district, rift valley province, kenya. 3 collection techniques were used: aspiration, sticky paper trap, and light trap in sites selected because of their proximity to homes of visceral leishmaniasis patients diagnosed and treated within 6 months before the survey. over 2000 female phlebotomus martini were collected of which 6 females were found to have flagellate protozoan infections. 3 of these infections were cultured successf ... | 1988 | 3252587 |
| supplemented schneider's drosophila medium for isolation of leishmania donovani promastigotes. | | 1988 | 3252764 |
| [active antihelminitic alkaloids: active in vitro against leishmanic tropica the protozoa involved in leishmaniasis]. | leishmaniasis caused by protozoan leishmania ssp., is an endemic parasitic disease in central and south america. the chemotherapeutic agents against leishmania ssp. (pentavalent antimony compounds, pentamidine and amphothericine b) are toxic and expensive products. basing on the bolivian folk medicine, we tried to find new active principles. fourteen isoquinoline alkaloids, especially bisbenzylisoquinoline alkaloids extracted from annonaceae, berberidaceae, hernandiaceae and menispermaceae, demo ... | 1988 | 3253497 |
| calcium as a possible second messenger of external signals in leishmania donovani. | | 1988 | 3253500 |
| development of monoclonal antibodies to assay for circulating antigen in visceral leishmaniasis. | | 1988 | 3253509 |
| experimental infection of the naked mole-rat, heterocephalus glaber, with leishmania donovani. | | 1988 | 3256107 |
| epidemiological studies on american leishmaniasis in ceará state, brazil. molecular characterization of the leishmania isolates. | two methods of molecular characterization, using monoclonal antibodies and enzyme electrophoresis, were employed in the identification of 36 stocks of leishmania isolated from human and canine cases of american visceral (avl) and cutaneous (acl) leishmaniases in the northern part of ceará state, brazil. molecular homogeneous strains of leishmania donovani (chagasi) isolated from both human and canine hosts were detected in 14 municipalities. two more parasite species, l. braziliensis braziliensi ... | 1988 | 3256276 |
| canine visceral leishmaniasis at wadi hamam, in israel. | a preliminary survey of canine leishmaniasis was made in israel by serodiagnosis, using a direct and competitive enzyme-linked immunosorbent assay. three (4%) of the 75 dogs surveyed were seropositive. the infected dogs came from wadi hamam near tiberias in northern israel. parasites isolated from one dog by needle aspiration were identified as leishmania donovani sensu lato by their excreted factor. | 1988 | 3256986 |
| clinical and immunological responses following accidental inoculation of leishmania donovani. | | 1988 | 3256987 |
| visceral leishmaniasis in man and dogs in south-west saudi arabia. | | 1988 | 3256988 |
| the discovery and preliminary characterization of a novel trypanosomatid parasite from rattus norvegicus and stray dogs from alexandria, egypt. | a survey of rodents and dogs was carried out in alexandria and its environs to see if an animal reservoir was associated with an outbreak of infantile kala-azar in this area. three rodent species, rattus rattus, rattus norvegicus and mus musculus, were commonly trapped and examined. a flagellate parasite was isolated from the spleens of two r. norvegicus. it was typed serologically by excreted factor serotyping and enzymologically by thick starch electrophoresis of four of its enzymes: gpi, g6pd ... | 1988 | 3257073 |
| suppression of il-2 production by cryopreserved peripheral blood mononuclear cells from patients with active visceral leishmaniasis in sicily. | the ability of pbmc from eight patients with confirmed visceral leishmaniasis (leishmania donovani) to produce il-2 in response to pha in vitro was investigated. pbmc from the patients produced significantly lower levels of il-2 and had reduced proliferative response to pha at the time of disease diagnosis compared with healthy controls. their ability to produce il-1 in response to lps was, however, unaltered. the patients also showed normal levels of okt4+ and il-2r+ cells in the peripheral blo ... | 1988 | 3258620 |
| isolation of protective t cells from balb/cj mice chronically infected with leishmania donovani. | balb/cj mice, which are homozygous for lshs on chromosone 1, are genetically susceptible to leishmania donovani (s3), but spontaneously reduce their parasite burdens late in the course of infection. spleens from chronically infected mice (5 to 8 mo) were found to have t cells that responded to leishmanial ag by proliferating and secreting immune ifn. an ifn-secreting t cell line derived from the spleen of a chronically infected mouse, after boosting with leishmanial ag and treatment with pentost ... | 1988 | 3262649 |
| protective t cell responses in balb/c mice infected with leishmania donovani. | | 1988 | 3267035 |
| immunodiagnosis of kala-azar by elisa using intact promastigote. | | 1988 | 3268597 |
| american cutaneous leishmaniasis: presentation and problems of patient management. | | 1988 | 3271359 |
| record of flagellate infection in phlebotomus argentipes in some kala azar endemic areas of bihar, india. | | 1988 | 3271754 |
| [contribution of the duodenal biopsy in the diagnosis of kala-azar]. | | 1986 | 3275397 |
| long term cryopreservation of the amastigote stages of hemoflagellates. | tissue homogenates containing amastigotes of either leishmania donovani, l. tropica, or trypanosoma cruzi were rapidly frozen with 10% glycerol as cryoprotectant. viability and pathogenicity were maintained for at least 23 years with the khartoum strain of l. donovani, 22 years with the malakal strain of l. donovani, and 7 years for l. tropica and t. cruzi. similar results over a shorter period of time were obtained with a slow-freezing technique. | 1988 | 3284997 |
| the dynamics of granuloma formation in experimental visceral leishmaniasis. | we have examined the temporal sequence of events leading to the formation of hepatic granulomas after the intravenous injection of l. donovani amastigotes into balb/c mice. parasite ingestion by permissive kupffer cells (kc) occurred promptly, and local kc aggregations were the foci about which granulomas were subsequently formed. infected kc were recognized by the uptake of colloidal carbon and the expression of the macrophage-specific antigen recognized by f4/80 mab. peroxidase-positive granul ... | 1988 | 3290381 |
| identification of leishmania donovani amastigotes in canine tissues by immunoperoxidase staining. | this paper describes the demonstration of leishmania donovani amastigotes in canine tissues by immunoperoxidase staining. an indirect immunoperoxidase method was applied to the organs of 20 dogs in which leishmaniasis was previously diagnosed. haemosiderin pigment was eliminated with 5 per cent oxalic acid. amastigotes of l donovani appeared as dark brown stained bodies which contrasted with haematoxylin stained host cells. no positively stained amastigotes could be seen in any of the sections i ... | 1988 | 3291029 |
| immunization of dogs with a leishmania infantum-derived vaccine. | a partially-purified extract of leishmania infantum has been administered to healthy dogs. post-immunization sera were found to neutralize the infectivity of l. infantum and to abate the development of l. major. muramyl dipeptide and one of its derivates, murabutide, were the best adjuvants. | 1988 | 3291382 |
| complement receptor type 3 (cr3) binds to an arg-gly-asp-containing region of the major surface glycoprotein, gp63, of leishmania promastigotes. | the major surface glycoprotein of leishmania promastigotes, gp63, was isolated and reconstituted into a lipid membrane immobilized on the surface of 5-micron-diameter silica beads. these beads bound to the macrophage (mo), and the extent of binding correlated with the density of gp63 on the bead. the bead thus facilitated analysis of the binding specificity of a single ligand, gp63, without contribution from other molecules present on the surface of intact promastigotes. plating of mo onto subst ... | 1988 | 3294332 |
| monoclonal antibody identification of leishmania tropica from sudanese mucosal leishmaniasis. | monoclonal antibodies have been raised against a stock of leishmania parasites which were isolated from a patient with mucocutaneous leishmaniasis in the sudan. this stock did not react with monoclonal antibodies to l. donovani, and monoclonal antibodies raised to this stock were not reactive with stocks of l. donovani. they did react with stocks of l. tropica. the antibodies recognized antigens of high and of low molecular weights which were detectable in immunofluorescence on cultured promasti ... | 1987 | 3299657 |
| identification of the promastigote surface protease in seven species of leishmania. | twelve different strains of leishmania, including l. major, l. donovani, l. infantum, l. tropica, l. mexicana, l. amazonensis, l. braziliensis, and l. enriettii were examined for the presence of an ectoenzyme structurally and functionally related to the promastigote surface protease found in l. major lem 513. all strains examined possess a protease that is labelled by surface iodination of living promastigotes. the electrophoretic migrations of the labelled proteases are similar in all species s ... | 1987 | 3302702 |
| comparative study of the virulence of two leishmania donovani isolates of different origin. | the virulence of two isolates of leishmania donovani (lmu-6 isolated from a human case in ethiopia and lmu-16 isolated from an asymptomatic dog in the south-east of spain) in balb/c and c57bl/6 mice and in hamsters was observed over a period of 14 weeks. regular measurements of the liver parasite burdens and observations of external signs of infection were made, and the humoral and delayed type hypersensitivity responses were tested. no major differences were observed in the infection patterns p ... | 1986 | 3307656 |