| surface antigens on a kenyan strain of leishmania donovani. | | 1983 | 6628296 |
| high efficiency plating method for leishmania promastigotes in semidefined or completely-defined medium. | a simple technique, developed for the isolation of clones derived from single, promastigote cells of leishmania donovani and leishmania tropica, involved the use of semisolid agar. both species of leishmania promastigotes formed discrete colonies at high efficiency either in semidefined medium containing 10% fetal calf serum or in completely-defined medium lacking serum. visible colonies appeared between 8 and 14 days in growth medium containing 10% fetal calf serum. replacement of the fetal cal ... | 1983 | 6631633 |
| non-specific and specific stimulation of resistance against leishmania donovani in c57bl/6 mice. | stimulation by intravenous injections of glucan, a beta 1,3 polyglucose, provided a significant degree of resistance in mice against leishmania donovani. the response of c57bl/6 animals was dose-dependent. a single glucan injection before or after infection induced significant resistance but to a lesser degree than two or three injections. immunization by injections of formalin-killed promastigotes with glucan via the subcutaneous or intravenous routes provided greater resistance than glucan or ... | 1983 | 6638931 |
| testicular amyloidosis in hamsters experimentally infected with leishmania donovani. | thirty hamsters were inoculated intraperitoneally with leishmania donovani. testes were examined grossly and histologically by light and electron microscopy. progressive testicular atrophy developed. spermatogenic cells of the seminiferous tubules showed vacuolar degeneration and decreased in number leading to a total azoospermia in the final weeks of the pathological process. lymphoplasmocytic infiltrates with macrophages containing leishmanias appeared in the intertubular space. amyloid deposi ... | 1983 | 6639870 |
| antiactin and antitubulin antibodies in canine visceral leishmaniasis. | visceral leishmaniasis, a chronic and often fatal disease, is caused by the protozoan parasite leishmania donovani. both specific and nonspecific antibodies are produced in the course of the disease, and autoantibodies may be involved in pathogenesis. tubulin and actin have been found to be associated with l. donovani. to learn whether antiactin and antitubulin antibodies are present in visceral leishmaniasis, we tested sera from 263 infected dogs by enzyme-linked immunosorbent assay for antibod ... | 1983 | 6642639 |
| cell-mediated immune response in indian kala-azar and post-kala-azar dermal leishmaniasis. | cell-mediated immune (cmi) response in 16 indian kala-azar (ka) and 12 post-kala-azar dermal leishmaniasis (pkadl) patients was studied in detail by in vitro lymphocyte transformation experiments and by in vivo skin testing. peripheral blood lymphocytes of active ka patients failed to be stimulated by leishmania antigen. on the other hand, lymphocytes from a majority of the active ka patients could be stimulated by phytohemagglutinin. active ka patients also failed to show delayed type hypersens ... | 1983 | 6642649 |
| effect of berberine chloride on leishmania donovani. | | 1983 | 6674161 |
| immunoprophylaxis against kala-azar. iva. immunization of golden hamsters and hissar strain albino mice against leishmania donovani (an exploratory study). | | 1983 | 6677687 |
| a case of tonsillar leishmaniasis. | primary mucous leishmaniasis of the tonsil with satellite lymphatic spread but without visceral diffusion is presented. from fragments of the tonsils and from the satellite cervical lymph nodes it was possible to find, isolate and culture a strain of leishmania donovani 'bo 72'. the diagnostic problems are discussed caused by the lack of specific clinical findings and the rarity of mucous leishmaniasis in an area frequently the site of other pathological processes. | 1984 | 6693825 |
| pathologic changes in murine leishmaniasis (leishmania donovani) with special reference to the dynamics of granuloma formation in the liver. | the histopathologic changes in liver, spleen, and bone marrow of balb/c mice infected for 6 months with leishmania donovani are described. granulomas were the most important histologic lesions found; and the dynamics of their formation, collagen deposition, and resolution in the liver were studied. the number of hepatic granulomas increased until the eighth week and then decreased steadily. in contrast to the liver granulomas, those of spleen and bone marrow do not mature or show collagen deposi ... | 1984 | 6696043 |
| expression of the natural resistance gene lsh in resident liver macrophages. | innate resistance and susceptibility to leishmania donovani infection in mice is controlled by a single gene (lsh) thought to be identical to the genes ity and bcg which control the early response to salmonella typhimurium and mycobacterium bovis infections, respectively. in the present study, three new aspects of lsh gene activity were demonstrated. first, it was shown that liver macrophages continue to express lsh gene activity in vitro after their extraction from mice infected in vivo, althou ... | 1984 | 6698599 |
| expression of an unusual acidic glycoconjugate in leishmania donovani. | an acidic glycoconjugate containing mannose, galactose and phosphate in approximately equimolar amounts was extracted from leishmania donovani promastigotes and partially characterized. the glycoconjugate could be metabolically labeled with either [3h]mannose or [3h]galactose and was extractable from a delipidated residue fraction with water/ethanol/diethyl ether/pyridine/concentrated nh4oh (15:15:5:1:0.017) at 25 degrees c. the radioactively labeled glycoconjugate was found to possess the follo ... | 1984 | 6706985 |
| visceral leishmaniasis in the german shepherd dog. i. infection, clinical disease, and clinical pathology. | two groups of three german shepherd dogs each were inoculated with leishmania chagasi or leishmania donovani amastigotes and the infection was followed for 82 days. the dogs developed a persistent infection, became thin, and developed splenomegaly and lymphadenomegaly by 55 days after inoculation. all dogs developed a normocytic, normochromic anemia of increasing severity. thrombocytopenia and leukopenia occasionally occurred. blood tryptophan levels were decreased significantly in infected dogs ... | 1984 | 6710816 |
| visceral leishmaniasis in the german shepherd dog. ii. pathology. | three german shepherd dogs were inoculated with leishmania chagasi and three with leishmania donovani and the infection was followed for 82 days. all infected dogs developed splenomegaly and lymphadenomegaly. in lymph nodes there was a reduction in lymphocyte population in paracortical areas, extensive proliferation of macrophages in paracortical areas and medullary cords, follicular hyperplasia, and increased numbers of plasma cells. the spleen had decreased numbers of lymphocytes in periarteri ... | 1984 | 6710817 |
| biological action of inosine analogs in leishmania and trypanosoma spp. | previous investigations have suggested that inosine analogs would be good models for the development of chemotherapeutic agents active against pathogenic hemoflagellates. we have systematically modified the five-membered heterocyclic ring of six inosine analogs and tested them for their antiprotozoal activities and toxicity to a mammalian cell line. all six analogs were very active against the three protozoan pathogens leishmania donovani, trypanosoma cruzi, and trypanosoma gambiense. two of the ... | 1984 | 6712205 |
| cold agglutinin syndrome and hemophagocytosis in systemic leishmaniasis. | a 3-year-old male child with high fever, hepatosplenomegaly, pancytopenia, haemolysis, striking histiocytosis and hemophagocytosis in bone marrow aspiration and high titre of cold agglutinin is described. cold agglutinins were defined as polyclonal igm with anti-i specificity. diagnosis of visceral leishmaniasis was made on the basis of typical leishman-donovan bodies found in the patient's bone marrow, high titre of anti-leishmania antibodies and excellent response to treatment. visceral leishm ... | 1984 | 6719046 |
| single cell cloning of leishmania parasites in purine-defined medium: isolation of drug-resistant variants. | a simple technique for the isolation of leishmania donovani and leishmania tropica promastigote clones derived from a single cell involves the use of semi-solid agar. both species of leishmania form discrete colonies at high efficiency in completely defined medium lacking serum. visible colonies appear between eight and fourteen days. viability of colonies transferred from semi-solid agar to liquid suspension culture is 100%. using these techniques, we have isolated clonal populations of cells r ... | 1984 | 6720386 |
| affinity separation and partial characterization of serologically active leishmania donovani antigens. | leishmania donovani-soluble antigens capable of antibody production in rabbits were separated from the total antigenic make-up of the parasite by adsorption on to anti-leishmania immunoglobulins coupled to cnbr-activated sepharose 4b (alig). immune rabbit sera were produced either by intravenous inoculation of living promastigotes or by intradermal and subcutaneous inoculation of soluble antigens. approximately four times as much soluble antigen was bound to alig produced by i.v. than i.d. and s ... | 1984 | 6721613 |
| treatment of experimental visceral leishmaniasis with lymphokine encapsulated in liposomes. | highly susceptible mice were infected with leishmania donovani chagasi and were treated with supernatants, free or encapsulated in liposomes, from concanavalin a-stimulated or unstimulated mouse spleen cell cultures. treatment consisted of multiple i.v. injections beginning 2 days before to 2 days after infection. mice treated with lymphokine-rich supernatants encapsulated in liposomes had significantly fewer liver parasites than the control groups, demonstrating in vivo activity of lymphokine a ... | 1984 | 6725947 |
| intracellular destruction of leishmania donovani and leishmania tropica amastigotes by activated macrophages: dissociation of these microbicidal effector activities in vitro. | resident peritoneal macrophages were exposed to amastigotes of leishmania donovani and l. tropica and treated with soluble products of antigen or mitogen-stimulated lymphocytes (lymphokines, lk). macrophages infected with l. donovani were responsive to lower concentrations of lk for elimination of this parasite than cells infected with l. tropica, and the disappearance of l. donovani amastigotes from activated macrophages preceded that of l. tropica by at least 24 hr. that the differential elimi ... | 1984 | 6725948 |
| antileishmanial activity of liposome-encapsulated meglumine antimonate in the dog. | experimental infections of leishmania donovani in mixed-breed dogs were induced to determine the antileishmanial efficacy of liposome-encapsulated meglumine antimoniate ( lema ). each dog was inoculated iv with 1.0 +/- 0.2 x 10(8) amastigotes of a khartoum strain of l donovani/kg of body weight. the antileishmanial agents ( lema or unencapsulated meglumine antimoniate ) were given once daily, iv, for 1, 4, or 10 consecutive days beginning the 12th day after inoculation. the dogs were killed 3 or ... | 1984 | 6732008 |
| antileishmanial activity of chlorpromazine. | the antiprotozoal activity of chlorpromazine against the pathogenic protozoan leishmania donovani, in both its amastigote and promastigote stages, was characterized. chlorpromazine at concentrations greater than or equal to 3.12 micrograms/ml (9.8 x 10(-6) m) produced a significant reduction in viable promastigotes. the minimal protozoacidal concentration for promastigotes, defined as that concentration which produced greater than or equal to 90% reduction in viable parasites after 18 h, was 13. ... | 1984 | 6732225 |
| monophosphates of formycin b and allopurinol riboside. interactions with leishmanial and mammalian succino-amp synthetase and gmp reductase. | formycin b 5'-monophosphate (form b-mp) and allopurinol riboside 5'-monophosphate ( hppr -mp) are isomers of imp that are metabolically produced when leishmania spp. are incubated with the antileishmanial agents formycin b and allopurinol or allopurinol riboside. the interactions of form b-mp with succino -amp synthetase and gmp reductase from both leishmanial and mammalian sources were compared with the data of earlier studies with hppr -mp. both analogs could substitute for imp as a substrate ... | 1984 | 6732835 |
| enzymes of carbohydrate metabolism in leishmania donovani amastigotes. | a method for the isolation of leishmania donovani amastigotes from infected hamster spleen and liver tissues is described. over 85% of the isolated amastigotes were viable as judged by acridine orange-ethidium bromide staining and in vitro transformation to the promastigote form. a comprehensive survey of the enzymes of carbohydrate metabolism in l. donovani amastigotes and promastigotes was conducted. amastigotes and promastigotes possess all of the enzymes of the embden-meyerhof pathway, hexos ... | 1984 | 6737317 |
| inbred mouse strain resistance to mycobacterium lepraemurium follows the ity/lsh pattern. | inbred mouse strains and their f1 hybrids infected intravenously with mycobacterium lepraemurium showed different mean survival times (mst). balb/c and c57bl mice were particularly susceptible, whereas c3h, cba and dba/2 mice were relatively resistant. resistance as judged by mst was dominant in the f1 hybrids. a similar ranking order was obtained by comparing the doubling time of the bacillus in the bone marrow, the increase in spleen weight between 4 and 12 weeks after infection, and the patho ... | 1982 | 6749659 |
| polyclonal b cell activation in hamsters infected with parasites of the genus leishmania. | mesocricetus auratus (golden hamsters) infected with leishmania developed characteristic b cell immune responses that depended on the infecting species of leishmania. thus, hamsters infected with viscerotropic leishmania (leishmania donovani) developed antileishmania antibodies and hypergammaglobulinemia due to polyclonal activation of b cells as measured by reverse hemolytic plaque assay. in contrast, dermotropic leishmanias (l. braziliensis braziliensis and l. mexicana amazonensis) stimulated ... | 1982 | 6759410 |
| immune complexes in indian kala-azar. | patients with indian kala-azar were investigated for the presence of circulating immune complexes by the platelet aggregation test, complement deviation test, and polyethylene glycol precipitation test. circulating antibodies were tested by the conventional indirect immunofluorescence test using leptomonad forms of leishmania donovani and crithidia luciliae. the serum complement level (c3) was measured using the mancini technique. the results indicate that a large number of patients with indian ... | 1982 | 6761008 |
| influence of h-2 complex on acquired resistance to leishmania donovani infection in mice. | innate susceptibility to leishmania donovani infection in mice (measured over 2--4 weeks) is under the control of a single autosomal gene (lsh) segregating for incompletely dominant resistant (r) and recessive susceptible (s) alleles. this locus maps away from the known histocompatibility loci to a position between the centromere and id-1 on the chromosome 1 of the mouse. amongst homozygous recessive lsh strains of mice two patterns of recovery are observed when the course of infection is follow ... | 1980 | 6765984 |
| leishmania donovani: action of excreted factor on hydrolytic enzyme activity of macrophages from mice with genetically different resistance to infection. | | 1980 | 6767620 |
| synthesis of 2,4-disubstituted 6-methoxy-8-aminoquinoline analogues as potential antiparasitics. | a series of 2,4-disubstituted 8-aminoquinoline analogues were synthesized and evaluated against plasmodium berghei in mice and leishmania donovani in hamsters. 8-[[6-(diethylamino)hexyl]amino]-2-ethyl-6-methoxy-4-methylquinoline (8a) possessed significant activity against l. donovani. 2-ethyl-4-methylprimaquine (7a) was evaluated against plasmodium cynomolgi in rhesus monkey and found to have activity equal to that of primaquine. | 1980 | 6770089 |
| 4,5-disubstituted primaquine analogs as potential antiprotozoan agents. | 4,5-dimethylprimaquine and 5-fluoro-4-methylprimaquine were synthesized and evaluated against plasmodium berghei in the mouse. significant blood schizonticidal activity was observed. the 5-fluoro-4-methylprimaquine analog also was active as a tissue schizonticidal agent when evaluated against p. cynomolgi in the rhesus monkey, as an antileishmanial agent when evaluated against leishmania donovani in the hamster, and as a causal prophylactic agent when evaluated against p. berghei yoelii. | 1980 | 6772756 |
| salmonella paratyphi a in hamsters concurrently infected with schistosoma mansoni. | the present work deals with the development of an improved animal model to study the association of salmonellosis and schistosomiasis. the animal chosen was the hamster, mesocricetus auratus, which can be readily infected with schistosoma mansoni. normal hamsters and schistosome-infected hamsters (sih) were given approximately 2.0 x 10(7) salmonella paratyphi a intracardially. it was found that s. mansoni infections enhanced and prolonged the growth of s. paratyphi a in hamsters. animals with du ... | 1981 | 6786117 |
| immunoglobulin g and immunoglobulin m polar staining of toxoplasma gondii in the indirect immunofluorescence test. | polar staining (ps) of toxoplasma gondii in the indirect immunofluorescence test has been considered a nonspecific reaction caused exclusively by certain immunoglobulin m (igm) antibodies and confined to the anterior end of the parasite. after we observed a patient with positive serology for chagas' disease who presented an igg ps reaction, we studied sera from 120 patients with chagas' disease, 20 sera from patients with leishmania donovani infection, and 30 sera from patients with leishmania b ... | 1980 | 6796601 |
| immunization of mice against leishmania donovani by subcutaneous injections of dead promastigotes. | mice immunized by a series of intravenous, intraperitoneal or subcutaneous injections of formalin-killed leishmania donovani promastigotes with glucan, a beta 1, 3 polyglucose, exhibited a significant degree of resistance against subsequent infection with viable promastigotes. intramuscular immunization was not effective. immunization via subcutaneous injections of dead promastigotes simultaneously with glucan elicited protective resistance, positive skin test responsiveness before and after cha ... | 1983 | 6824127 |
| synthesis and antileishmanial activity of 6-methoxy-4-methyl-n-[6-(substituted-1-piperazinyl)hexyl]-8-quinolinamines and related compounds. | the 8-quinolinamine, 4-[6-[6-methoxy-4-methyl-8-quinolinyl)amino]hexyl]-1-piperazineethanol (1b), has been shown to be highly effective against leishmania donovani infections in hamsters. in an effort to obtain a more potent, less toxic 8-quinolinamine, a series of analogues (2) was prepared that examined particularly the structural requirements of the terminal piperazine moiety. of the substituted piperazines and alternative heterocycles prepared, as well as those quinoline analogues with ring ... | 1983 | 6827535 |
| interaction of leishmania donovani promastigotes with human phagocytes. | leishmania donovani is an important intracellular protozoal pathogen of humans, which resides solely within mononuclear phagocytes. phase-contrast microscopy and cinemicroscopy were used to examine the interaction of l. donovani promastigotes with human phagocytes to characterize and quantitate the sequence of events that results in leishmanial infection. | 1983 | 6832834 |
| comparison of microscopy and culture in the detection of leishmania donovani from splenic aspirates. | three culture media were compared with giemsa-stained smears for the detection of leishmania in splenic aspirates from kenyan patients with visceral leishmaniasis. ninety-nine splenic aspirates obtained from 26 patients at various times before, during, and after treatment were cultured in schneider's drosophila medium and rpmi medium 1640 (each supplemented with 20% fetal bovine serum) and mcconnell's modification of senekje's medium overlayed with 0.9% saline. from 13 splenic aspirates obtained ... | 1983 | 6837840 |
| leishmania tropica and leishmania donovani: solid phase radioimmunoassay using leishmanial excreted factor. | a radioimmunoassay for the quantitative determination of anti-leishmanial excreted factor (ef) antibody in rabbit sera was developed. the assay, using leishmania tropica and leishmania donovani promastigotes ef, purified by either extraction with phenol followed by fractionation on a sephadex g-100 column or by the dissociation of ef antibody complexes, was shown to be sensitive and reproducible. using monospecific anti-ef antibodies, levels of as low as 0.06-0.12 micrograms/ml of anti-ef igg co ... | 1983 | 6852165 |
| immunogenicity of soluble and particulate antigens from leishmania donovani: effect of glucan as an adjuvant. | the protective efficacy of glucan as an adjuvant with killed promastigotes of leishmania donovani was compared with that of soluble or particulate fractions of the parasite. when these vaccine preparations were injected either intravenously or subcutaneously in cf-1 mice, glucan potentiated resistance against l. donovani infections as reflected by significant reductions in hepatic amastigote counts relative to infected control mice. the leishmanial antigens alone afforded no protection. serum di ... | 1983 | 6852909 |
| surface antigens of leishmania donovani promastigotes. | surface antigen profiles of leishmania donovani promastigote isolates have been studied. surface patterns of brazilian and african isolates display remarkable similarities and are extremely simple, consisting of three major peptides of 65,000, 25,000, and 23,000 mol wt. surface iodination and biosynthetic labeling coupled to immunoprecipitation techniques revealed that a single major determinant of 65,000 mol wt is recognized in all strains by sera from kala-azar patients from both brazil and af ... | 1983 | 6854205 |
| relative insensitivity of a kenyan strain of leishmania donovani to pentavalent antimony therapy in hamsters. | | 1983 | 6854484 |
| regulation of leishmania populations within the host. v. resistance to l.donovani in wild mice. | samples of wild mus musculus from two populations in areas endemic for leishmaniasis and from seven populations in non-endemic areas were found to be uniformly resistant when tested for their early response to leishmania donovani infection. males from one endemic and one non-endemic population were crossed to females from two inbred strains of mice carrying the susceptible allele for the innate resistance gene, lsh, on different genetic backgrounds. bimodality of liver parasite counts and a clos ... | 1983 | 6854699 |
| quantitation of amastigotes of leishmania donovani in smears of splenic aspirates from patients with visceral leishmaniasis. | during a 20-month period, more than 500 splenic aspirations were performed in 89 patients with suspected or proven visceral leishmaniasis. the two complications which occurred (intra-abdominal bleeding and penetration of the intestine in one patient each) both resolved with conservative management. parasite density in splenic aspirate smears was graded on a logarithmic scale from 0 (no parasites in 1,000 microscopic fields) to 6+ (greater than 100 parasites per microscopic field). among 46 newly ... | 1983 | 6859397 |
| complement increases in experimental leishmania donovani infection of the golden hamster. | | 1981 | 6908884 |
| cellular immunity of mice to leishmania donovani in vitro: lymphokine-mediated killing of intracellular parasites in macrophages. | leishmania donovani, an intracellular protozoan, causes kala-azar by parasitizing the macrophages of its mammalian host. outbred ncs and cd-1 mice develop immunity to this parasite. this immunity was demonstrable when supernatant fluids from cultured splenic lymphocytes were added to infected macrophages. only the lymphokine preparations from infected mice showed significant leishmanicidal activity. mice receiving multiple inocula were more potent producers of leishmanicidal lymphokines than wer ... | 1981 | 6947274 |
| control of natural resistance to salmonella typhimurium and leishmania donovani in mice by closely linked but distinct genetic loci. | inbred strains of mice vary in their sensitivity to infection with both salmonella typhimurium and leishmania donovani. in both cases, this differential susceptibility is genetically controlled. resistance to the intracellular parasite l. donovani is determined by a single locus on chromosome 1, designated lsh (ref. 4). the primary regulator of resistance to s. typhimurium is a single, dominant autosomal gene, named ity (for immunity to typhimurium), and it has also been recently mapped to chrom ... | 1980 | 7001248 |
| the in vivo and in vitro action of 4-amino-5-imidazolecarboxamide in trypanosomatid flagellates. | 4-amino-5-imidazolecarboxamide, but not its riboside or ribotide, is inhibitory to the growth of promastigotes of leishmania donovani, l. braziliensis, l. tarentolae, and l. mexicana, eventually causing cell lysis. conversely, it is not inhibitory to the growth of epimastigotes of trypanosoma cruzi. this substituted imidazole proved to be an excellent inhibitor of guanine deaminase from all of the trypanosomatids used in this study, with ki values in the microm range. | 1981 | 7029273 |
| characterization of populations of promastigotes of leishmania donovani. | promastigotes of leishmania donovani cultured for either 3 or 10 days in vitro and inoculated intracardially into golden hamsters with an equal number of organisms from either population showed a 7-fold difference in infectivity when compared at both 10 and 16 days post-infection. reproducible histochemical staining for the promastigote enzymes glucose-6-phosphate dehydrogenase (g6pdh) and peptidase after polyacrylamide gel electrophoresis showed two isoelectric variants of g6pdh (bands 1 and 2) ... | 1981 | 7031232 |
| leishmania donovani, plasmodium berghei, trypanosoma rhodesiense: antiprotozoal effects of some amidine types. | | 1981 | 7032963 |
| adenylosuccinate synthetase and adenylosuccinate lyase from trypanosoma cruzi, specificity studies with potential chemotherapeutic agents. | adenylosuccinate (succino-amp) synthetase and succino-amp lyase isolated from epimastigotes of trypanosoma cruzi by chromatography on phosphocellulose. the synthetase was capable of catalyzing the condensation of aspartic acid with imp and several imp analogs. the reaction with allopurinol ribonucleotide is of potential chemotherapeutic interest. this analog was slowly converted to its corresponding succino-amp analog with a km' of 140 micrometers (cf. imp at 10 micrometers) and a vmax' of 0.3 p ... | 1982 | 7037007 |
| purine and pyrimidine salvage pathways in leishmania donovani. | leishmania donovani, grown in culture, salvaged radiolabeled purine bases which were distributed into adenine and guanine ribonucleotides and into the rna of these cells. de novo synthesis of purines in l. donovani does not occur [j. j. marr, r. l. berens and d. j. nelson, biochim. biophys. acta 544, 360 (1978)]. [8-14c]adenine was rapidly deaminated to hypoxanthine via the action of an adenine aminohydrolase (ec 3.5.4.2). [8-14c]guanine was also rapidly deaminated by guanase (ec 3.5.4.3) to for ... | 1982 | 7059364 |
| metabolism of 1-0-[1'-14c]octadecyl-sn-glycerol in leishmania donovani promastigotes. ether lipid synthesis and degradation of the ether bond. | a long-chain 0-alkylglycerol, 1-0-[1'-14c]octadecyl-sn-glycerol, was taken up and metabolized extensively in leishmania donovani promastigotes grown on a lipid-free, semi-defined medium as well as on a lipid-free, synthetic medium in nearly identical ways. cleavage of the ether bond was the main event even after short incubation times (1 h) and low precursor concentration (2 microm), as judged from the appearance of radioactive acyl moieties residing mainly in phosphatidylcholine. in addition, l ... | 1982 | 7078578 |
| cell-mediated immune response in experimental visceral leishmaniasis. i. correlation between resistance to leishmania donovani and lymphokine-generating capacity. | | 1982 | 7086136 |
| killing of leishmania donovani. amastigotes by murine macrophages. | | 1982 | 7090913 |
| genetics of resistance to infection with special reference to leishmaniasis. introduction, and genetics of susceptibility to leishmania donovani. | | 1982 | 7101398 |
| failure of the phagocytic oxidative response to protect human monocyte-derived macrophages from infection by leishmania donovani. | | 1982 | 7108206 |
| identification and partial characterization of an extracellular acid phosphatase activity of leishmania donovani promastigotes. | an extracellular acid phosphatase was detected in the growth media of leishmania donovani promastigotes. the enzyme was released at all stages of the growth cycle and in amounts which accounted for 90% of the total amount of this enzyme in the culture. the exoenzyme exhibited a ph optimum of 4.5 to 5.0 and was active with a variety of organic phosphates. the enzymatic activity was excluded from sephacryl s-300 and was retained by ultrafilters with nominal molecular weight cutoffs of up to 300,00 ... | 1982 | 7110130 |
| cell surface origin of antigens shed by leishmania donovani during growth in axenic culture. | antisera against isolated cell surface preparations (pcsp-as) of leishmania donovani promastigotes were used to detect extracellular antigens produced during the growth of these organisms in four different growth media. the pcsp-as precipitated two major antigenically identical but electrophoretically distinct components, in addition to several minor antigens. immunoelectrophoretic studies employing pcsp-as, pcsp-as absorbed with intact, live promastigotes, and pcsp-as absorbed with a major extr ... | 1982 | 7118250 |
| [experimental transmission of the causative agent of visceral leishmaniasis, leishmania donovani, to golden hamsters by phlebotomus longiductus, parr. 1928 and phlebotomus smirnovi, perf. 1941 sandflies]. | | 1982 | 7121405 |
| partial purification and characterization of particulate acid phosphatase of leishmania donovani promastigotes. | 1. more than 90% of the total acid phosphatase activity in a sonicate of l. donovani promastigotes is contained in a particulate fraction (200,000 x g 30 min). the enzyme can be quantitatively extracted and solubilized with the aid of triton x-100 (0.2 g/100 ml) and purified over 200-fold with 54% yield by chromatography on deae-sephadex, qae-sephadex, sepharose 4b and concanavalin-a sepharose. 2. the phosphatase is a true acid hydrolase (ph optimum, 5.0-5.5) and has a rather broad substrate spe ... | 1982 | 7128111 |
| protective effect of glucan against visceral leishmaniasis in hamsters. | the effect of pre- or posttreatment with glucan, a reticuloendothelial stimulant, on the course of leishmania donovani infection was assessed in highly susceptible hamsters. intravenous administration of glucan before or after l. donovani infection significantly suppressed proliferation of amastigote-stage parasites in liver and spleen. glucan-activated peritoneal macrophages in vitro also significantly reduced multiplication of the intracellular parasite. ultrastructural studies revealed a well ... | 1982 | 7129637 |
| pathogenesis of anaemia in hamsters infected with leishmania donovani. | the development of anaemia was studied in hamsters infected with leishmania donovani. haematocrit studies as well as erythrocyte survival studies using radioactive chromium (51cr), gave evidence of a progressive anaemia during the course of infection. the erythrocytes were positive in direct antiglobulin tests using antisera to igg and complement c3. moreover, erythrophagocytosis as well as increased deposits of haemosiderin in the liver and the spleen, particularly in the areas of proliferating ... | 1982 | 7136193 |
| ultrastructure of amastigotes of leishmania donovani in the bone marrow of a dog. | visceral leishmaniasis was diagnosed in a dog which had been in spain for 4 years before being brought to florida. a bone marrow aspirate from the dog was examined by electron microscopy. phagocytized amastigotes by macrophages had an electron-dense plasma membrane and contained ribosomes, rough endoplasmic reticulum, a well-developed golgi apparatus, an intracellular flagellum, lipid, a kinetoplast, a row of microtubules immediately beneath the cell membrane, and a nucleus with marginated chrom ... | 1982 | 7149419 |
| the metabolism of formycin b in leishmania donovani. | | 1982 | 7150292 |
| host-parasite relationship in murine leishmaniasis: pathophysiological and immunological changes. | the host-parasite relationship in human visceral leishmaniasis remains poorly understood. in the present study, pathophysiological and immunological changes were examined in balb/c mice infected with leishmania donovani. these animals developed chronic infection with massive hepatosplenomegaly and hypergammaglobulinemia. in contrast to mice inoculated with 0.8 x 10(6) or 4 x 10(6) amastigotes, mice infected with 20 x 10(6) amastigotes failed to reduce liver parasite loads during 2 to 8 weeks of ... | 1982 | 7152667 |
| an easily prepared two phase medium for cultivation of leishmania donovani. | | 1982 | 7153479 |
| [comparative study of the antigenic properties and virulence of leishmania clones (trypanosomatidae, leishmania)]. | a relation between antigenic properties and virulence of leishmania clones were studied. the clones were obtained from a naturally infected sandfly (phlebotomus of the group caucasicus) caught in the burrow of great gerbil in turkmenia. antigenic properties of the clones were studied by means of adler's test (safjanova's modification); the virulence of the clones was studied on golden hamsters by means of standard technique. there was revealed heterogenicity of the phlebotomus strain of leishman ... | 1982 | 7155626 |
| guanosine 5'-monophosphate reductase from leishmania donovani. a possible chemotherapeutic target. | gmp reductase was highly purified from promastigotes of leishmania donovani by chromatography on a single deae-cellulose column. bimodal substrate saturation curves resulted in a 1/v versus 1/[gmp] plot that curved downward above 40 microm gmp. the kinetic constants were, therefore, obtained with gmp below this concentration. the k'm for gmp was 21 microm at ph 6.9. the enzyme was very sensitive to activation by gtp. at 20 microm gmp, a maximum of 600% activation occurred at 100 microm gtp. half ... | 1982 | 7159467 |
| leishmaniasis in brazil: xviii. further evidence incriminating the fox cerdocyon thous (l) as a reservoir of amazonian visceral leishmaniasis. | major endemic areas of visceral leishmaniasis in brazil are located in the drier, poorly forested regions, principally in the northeastern states such as ceará and bahia. cases of the human disease in the amazon region are rare, very sporadic, and seldom present opportunities for epidemiological study. following the report of a fatal case near salvaterra, the island of marajó, pará state, a preliminary investigation has resulted in the isolation of a parasite regarded as leishmania donovani chag ... | 1982 | 7164150 |
| incorporation of [1-14c]acetate into fatty acids and aliphatic moieties of glycerolipids in leishmania donov ani promastigotes. | 1. short-time incubations (20-300 sec) of leishmania donovani with [1-14c] acetate showed lauric, myristic and palmitic acid to be labeled first, whereas from 150 sec on the radioactivity was mainly found in stearic and oleic acid. 2. after an incubation period of 7 days the distribution of radioactivity in fatty acids was similar to the mass distribution of fatty acids. 3. up to 300 sec 14c-activity was present mainly in acyl moieties of lipids (94%). 4. ether moieties of radylglycerols, dirady ... | 1982 | 7172630 |
| the effect of inhibitors on the respiration of leishmania donovani promastigotes from culture. | | 1982 | 7173076 |
| growth factor requirements for in vitro growth of leishmania donovani. | | 1982 | 7174005 |
| isolation and partial characterization of antigen from leishmania donovani promastigotes and its possible use in serodiagnosis. | | 1982 | 7174006 |
| temperature-dependent fatty acyl group changes in phospholipids of 37 c-adapted leishmania donovani promastigotes. | | 1982 | 7175608 |
| sensitization of offspring of leishmania donovani-infected hamsters to immunization and of offspring of immunized hamsters to challenge. | female hamsters, infected intracardially (i.c.) with 1.0--2.0 x 10(5) amastigotes of leishmania donovani produced offspring, following mating, which, when immunized subcutaneously with 1.0 x 10(7) amastigotes at 8 weeks of age, were more resistant to i.c. challenge 6 weeks later than were hamsters born to non-infected mothers. offspring of mothers infected with as many as 6.0 x 10(6) amastigotes demonstrated no greater capacity for immunization than did those of mothers infected with 1.0 x 10(5) ... | 1982 | 7201750 |
| a monophasic liquid medium (gd-nrc) for the cultivation of leishmania donovani. | | 1981 | 7229813 |
| spectral model of leishmaniasis in congenic strains of mice. | nineteen congenic, resistant strains of mice on c57bl/10scsn genetic background were infected with leishmania donovani and the course of infection quantitated. early in the infection, parasite burdens in the liver were similar for all strains, indicating that the parasite was able to establish, grow, and reproduce in the liver macrophages of each strain with equal facility. differences in acquired resistance, indicated by decreases in parasite burden, among the strains were first noted at day 21 ... | 1981 | 7229823 |
| protozoan parasite of humans: surface membrane with externally disposed acid phosphatase. | plasma membranes isolated from the protozoan parasite leishmania donovani were enriched in acid phosphatase (e.c. 3.1.3.2) activity. cytochemically, the enzyme was distributed uniformly on the surface of intact cells and was localized on the external face of isolated membranes. physical characteristics and orientation of the membrane-bound enzyme suggest that the organism is adapted for existence in hydrolytic environments. | 1981 | 7233189 |
| effect of temperature on multiplication of leishmania amastigotes within human monocyte-derived macrophages in vitro. | leishmania tropica, a cause of cutaneous leishmaniasis, multiplied more rapidly within human macrophages in vitro at 35 degrees c than at 37 degree c, and was almost completely eliminated at 39 degrees c. in contrast, leishmania donovani, the cause of the visceral leishmaniasis, multiplied equally well at 35 degrees c and at 37 degrees c,, and was only 40% eliminated at 39 degrees c. this in vitro study suggests that the localization of the two strains to cooler and warmer regions of the body, r ... | 1981 | 7235124 |
| leishmanicidal mechanisms of human polymorphonuclear phagocytes. | human phagocytes isolated from peripheral blood were infected in vitro with leishmania donovani amastogotes derived from infected hamster spleens. phagocytosis of the parasites occurred without specific opsonization and the phagocytic efficiency of various cell types was in the order: neutrophil greater than monocyte greater than eosinophil. light and electron microscopy showed that amastigotes were often degraded by polymorphonuclear phagocytes, but not by monocytes. ultrastructural cytochemist ... | 1981 | 7235125 |
| antibody-mediated inhibition of phagocytosis in leishmania donovani-human phagocyte interactions in vitro. | amastigotes and promastigotes of leishmania donovani were used as antigens for immunization of rabbits which produced anti-amastigote igg demonstrable by indirect immunofluorescent tests. effects of these and normal rabbit heat-inactivated sera on phagocytosis of amastigotes by a mixture of human mononuclear and polymorphonuclear phagocytes were studied in vitro. parasites and phagocytes at different ratios were mixed and incubated at 37 degree c for various time periods in the presence of these ... | 1981 | 7235126 |
| leishmania donovani: surface membrane acid phosphatase activity of promastigotes. | | 1981 | 7238722 |
| [further observations on the use of counterimmunoelectrophoresis (ciep) on cellulose acetate membrane (cellogel) in the diagnosis of visceral leishmaniasis (author's transl)]. | technique of counterimmunoelectrophoresis (ciep) on cellulose acetate membrane (cellogel) is described for diagnosis of (human and canine) visceral leishmaniasis (vl). various lots of antigen were grossly obtained from the liquid phase (10, 20 and 30 tubes respectively) of cultures of leishmania donovani by repeated freezing and thawing. sera from patients (and, in a few cases, dogs) with confirmed vl, other parasitic and non-parastic diseases (especially blood disorders and hepatosplenomegaly) ... | 1980 | 7244099 |
| changes in growth rate and infectivity of leishmania donovani subjected to various laboratory procedures. | | 1981 | 7245843 |
| interaction of leishmania donovani promastigotes with human monocyte-derived macrophages: parasite entry, intracellular survival, and multiplication. | leishmania donovani promastigotes were incubated with human monocyte-derived macrophages in vitro to assess the role of macrophages in the early stage of visceral leishmaniasis. adherent mononuclear cells, obtained from nonimmune human donors, were cultivated on glass cover slips for 5 days and then incubated with axenically grown promastigotes in the presence of heat-inactivated autologous serum. promastigotes attached to macrophages with either their flagellar or aflagellar ends, and macrophag ... | 1981 | 7251165 |
| susceptibility of leishmania to oxygen intermediates and killing by normal macrophages. | this study demonstrates that the promastigote form of virulent leishmania donovani and leishmania tropica are both deficient in endogenous enzymatic scavengers of h(2)0(2) (catalase, glutathione peroxidase) and susceptible to low fluxes of h(2)o(2) in a cell-free model. in addition, the killing of promastigotes by h(2)0(2) is markedly enhanced in the presence of a peroxidase and halide. promastigotes also readily trigger the macrophage oxidative burst including the generation of h(2)0(2), and mo ... | 1981 | 7252418 |
| interaction of leishmania with a macrophage cell line. correlation between intracellular killing and the generation of oxygen intermediates. | the promastigote form of leishmania donovani and leishmania tropica, the etiologic agents of visceral and cutaneous leishmaniasis, respectively, readily parasitize unstimulated j774g8 macrophage-like cells, whereas 80-95% of the same promastigotes are killed within resident macrophages from normal balb/c mice. this striking difference in intracellular anti-leishmanial activity correlated closely with the capacity to generate toxic oxygen intermediates. thus, after triggering with phorbol myrista ... | 1981 | 7252424 |
| immunization against leishmania donovani: glucan as an adjuvant with killed promastigotes. | mice were immunized by a series of intravenous injections of formalin-killed leishmania donovani promastigotes alone and combined with glucan, a beta 1,3 polyglucose derivative of baker's yeast. in three separate experiments animals were challenged with viable parasites on day 21, 40 or 80 after immunization. mice which received dead parasites and glucan exhibited resistance against challenge up to 80 days after immunization. animals which had been injected with glucan alone exhibited a lesser d ... | 1981 | 7258489 |
| inhibition of in vitro macrophage digestion capacity by infection with leishmania donovani (protozoa: kinetoplastida). | promastigotes of leishmania donovani transformed into amastigotes and survived in cultured macrophages. promastigotes of leptomonas costoris, a kinetoplastid parasite of water striders, transformed into amastigotes but did not survive in cultured macrophages. a significant difference in size between the two species of parasitic protozoa allowed development of a bioassay in which the in vitro digestion rate of l. costoris was taken as a measure of macrophage digestive capacity following preinfect ... | 1981 | 7264834 |
| leishmania donovani in the owl monkey (aotus trivirgatus) | | 1981 | 7268842 |
| phagocytosis and killing of the protozoan leishmania donovani by human polymorphonuclear leukocytes. | the role of polymorphonuclear leukocytes (pmn) in host defense against leishmania donovani, the protozoan that causes visceral leishmaniasis, is unknown. to assess the ability of pmn to ingest and kill the infecting promastigote stage of the organism, cytocentrifuge preparations were made from tumbled suspensions of 5 x 10(6) pmn, an equal number of promastigotes, and fresh human serum deficient in the 6th component of complement. 53 +/- 9% pmn were found to have 1 or more associated promastigot ... | 1981 | 7276565 |
| elimination of leishmania donovani amastigotes by activated macrophages. | tissue macrophages are the obligatory host cells for leishmania donovani, the causative agent of visceral leishmaniasis. in this study we sought to determine whether activated macrophages, as defined by the functional criterion of tumor cell cytotoxicity, were also able to exert a microbicidal effect on ingested l. donovani amastigotes. we found that mouse peritoneal macrophages activated by a variety of means exerted a cytotoxic effect on tumor cell targets but were not able to kill l. donovani ... | 1981 | 7287190 |
| ether lipid synthesis from enantiomeric medium-chain and long-chain o-alkyl-sn-glycerols in leishmania donovani promastigotes. | a medium-chain o-alkylglycerol, 1-o-[1'-14c]dodecyl-sn-glycerol, has been found to be incorporated into plasmenyl ethanolamine by leishmania donovani promastigotes as revealed by radio gas-liquid chromatography; however, the ether bond of the administered o-alkyl-glycerol was cleaved extensively as judged from the occurrence of radioactive acyl moieties. the labelling pattern produced by the radioactive 'natural' 1-o-octadecyl-sn-glycerol was similar though the latter served as a slightly better ... | 1981 | 7300856 |
| failure of hamster macrophages to discriminate between infective and noninfective promastigotes of leishmania donovani during attachment in vitro. | the attachment of infective and noninfective promastigotes of leishmania donovani to hamster macrophages derived from spleen, lymph nodes, and peritoneal exudate was studied in vitro. regardless of macrophage origin, no significant differences were observed between attachment of promastigotes that were infective and those that were noninfective for hamsters. | 1981 | 7309246 |
| evaluation of different culture media for isolation of leishmania donovani. | | 1980 | 7320480 |
| leishmania donovani-macrophage binding mediated by surface glycoproteins/antigens: characterization in vitro by a radioisotopic assay. | a radioisotopic assay was developed to quantitate the binding of leishmania donovani promastigotes to hamster peritoneal macrophages in vitro. the binding was temperature dependent and required no serum factors. binding was reduced by preloading macrophages with zymosan granules or unlabeled promastigotes, but not with latex leads or opsonized erythrocytes. binding was reduced by 10 mm egta that was reversible by the addition at an equimolar concentration of calcium, but not magnesium ions. sial ... | 1981 | 7322188 |
| [activation of the alternative complement pathway by promastigotes of leishmania donovani]. | | 1981 | 7323601 |
| ultrastructural changes in tissue forms of leishmania donovani before and after cryopreservation in liquid nitrogen. | | 1981 | 7324543 |
| single gene control of resistance to cutaneous leishmaniasis in mice. | a series of inbred, congenic resistant, and hybrid strains of mice were intradermally inoculated with 10(6) promastigotes of leishmania tropica. these mice were divided into susceptible and resistant groups using the criteria of lesion size, development of metastatic foci and skin-test reactivity. at 16 weeks of infection, resistant strains a/j, dba/1j, akr/j, cba/j, c3h/hej, nzb/binj, c57bl/6j, c57bl/10sn, b10.d2, b10.129(10m), and b10.ce(30nx) had completely resolved their lesions, while susce ... | 1981 | 7327625 |
| the culture of leishmania donovani in schneider's insect medium: its value in the diagnosis and management of patients with visceral leishmaniasis. | | 1981 | 7330950 |