TitleAbstractYear(sorted ascending)
intracellular development in vitro of trypanosoma dionisii of bats. 19715097838
interactions between macrophage cultures infected with trypanosoma dionisii, lymphocytes and macrophages. 19734784075
comparative studies of trypanosoma vespertilionis battaglia and trypanosoma dionisii bettencourt & franç diphasic blood agar media trypanosoma vespertilionis developed spheroid clusters as compared to rather long, sausage-shaped (sometimes branched) clusters formed by trypanosoma dionisii. the former species attained a greater population density (approximately 6 x 10(7) organisms/ml) than the latter (approximately 2 x 10(7) organisms/ml). greater numbers of epimastigotes, some in active binary divisions, were observed during the logarithmic phase of growth, and morphologic changes occurred durin ...1975495
comparative drug sensitivities of culture forms of trypanosoma cruzi and trypanosoma dionisii. 1977329144
role of hydrogen peroxide and peroxidase in the cytotoxicity of trypanosoma dionisii by human granulocytes.the mechanism of the cytotoxic reaction of leukocytes to trypanosoma dionisii was investigated. cytotoxicity was measured by release of [99mtc]pertechnetate from labeled protozoa. both granulocytes and lymphocytes were found to be cytotoxic to antibody-coated t. dionisii. the reaction was inhibited by diethyldithiocarbamate and by potassium cyanide, both of which inhibit myeloperoxidase. myeloperoxidase from azurophil granules was toxic to t. dionisii, provided that hydrogen peroxide was also pr ...1978213388
trypanosoma (schizotrypanum) dionisii: effect of various agents on attachment and entry to macrophages in vitro and on morphogenesis.the attachment and entry of trypanosoma dionisii to mouse peritoneal macrophages in vitro were studied. both occurred to a similar extent whether parasites were alive or heat-killed, and whether macrophages were obtained from normal or immunized mice. attachment occurred equally at 4 and 37 degrees c, but entry only occurred at the higher temperature. neither was affected by pretreatment of parasites with active or inactivated complement. entry, but not attachment, was inhibited by cytochalasin ...1978624937
trypanosoma (schizotrypanum) dionisii: influence of mouse peritoneal macrophages and calf sera on extracellular growth in vitro at 37 degrees c.macrophages and certain batches of sera were essential for extracellular multiplication of trypanosoma dionisii in vitro in medium 199 with 20% (v/v) calf serum at 37 degrees c. in mixtures of 'good' and 'bad' batches of sera, multiplication increased as the proportion of the former was increased. mixtures of 'bad' and 'intermediate' sera permitted virtually no growth. phagocytosis of parasites by macrophages was unaffected by different batches of sera, though reduced in medium 199 alone. replac ...1978650172
phagocytosis and killing of trypanosoma dionisii by human neutrophils, eosinophils and monocytes.the cell-mediated resistance of human leucocytes to trypanosoma dionisii, a bat parasite related to t. cruzi, was investigated. human peripheral blood neutrophils and monocytes were cytotoxic to t. dionisii as assessed by electron microscopy and by induction of 99mtc release from trypanosomes pre-labelled with [99mtc] pertechnetate. the enhancement of cytotoxicity by specific antiserum varied considerably from one individual to another. neither blood lymphocytes nor blood eosinophils induced 99m ...1979542324
inhibition of phagocytosis of trypanosome dionisii by pregnancy alpha-2 glycoprotein.trypanosome phagocytosis by normal polymorphonuclear leucocytes was studied in the presence of the pregnancy-associated alpha 2-glycoprotein (pag). a serum fraction containing pag at a concentration of 13.5 micrograms/ml significantly inhibited the uptake of trypanosoma dionisii when contrasted with an identically obtained male serum fraction devoid of pag (p less than .01). this finding of diminished trypanosome uptake in physiologic concentrations of pag could account for the suggested increas ...19817324112
evasion of the oxidative microbicidal activity of human monocytes by trypomastigotes of trypanosoma dionisii.trypomastigotes of trypanosoma dionisii, a stercorarian trypanosome from bats, are effectively killed by neutrophils from human peripheral blood but are less sensitive to the cytotoxic action of human monocytes. the mechanism of killing appears to involve peroxidase and hydrogen peroxide. trypomastigotes are as effective as epimastigotes in inducing the formation of hydrogen peroxide by effector cells. they are, however, less sensitive than epimastigotes to the cytotoxic effect of peroxidase and ...19816267544
[comparative electron microscope studies on the kinetoplast morphology of bat-trypanosomes and trypanosoma cruzi (author's transl)].comparative studies on the ultrastructural morphology of kinetoplasts of trypanosomes belonging to the subgenus schizotrypanum have been made. three isolates of trypanosoma vespertilionis and two strains of trypanosoma dionisii derived from european bats were tested. comparison was made also with two isolates from brasilian bats characterized as t. cruzi and two strains which were derived from two patients suffering from chagas' disease. in the epimastigote culture form of t. cruzi a typical con ...19817018104
mechanism of entry and development of trypanosoma dionisii in non-phagocytic cells.cultures of 'buffalo' (bison) lung (bl) cells were infected with epimastigotes or trypomastigotes of trypanosoma (schizotrypanum) dionisii derived from cultures in vitro, fixed after various periods of incubation at 37 degrees c and examined by light or electron microscopy. few if any epimastigotes entered the bl cells, but many trypomastigotes did so; they adhered to the cell surface within 2 h and then appeared to sink into furrows on the cell surface until engulfed in parasitophorous vacuoles ...19827166571
characterization of dolichol monophosphate- and dolichol diphosphate-linked saccharides in trypanosomatid flagellates.dolichol-p- and dolichol-p-p-linked saccharides were isolated from several trypanosomatid flagellates incubated with [u-14c]glucose. formation of glc-p-dolichol and man-p-dolichol was observed in herpetomonas muscarum and leishmania adleri, whereas only the latter derivative was synthesized in trypanosoma dionisii and leptomonas samueli. the main and largest dolichol-p-p-linked oligosaccharide formed in trypanosoma conorhini, t. dionisii, l. samueli, herpetomonas samuelpessoai and h. muscarum ap ...19863083254
characterization of protein-linked oligosaccharides in trypanosomatid flagellates.protein-linked, endo-beta-n-acetylglucosaminidase h-sensitive oligosaccharides were isolated from several trypanosomatids incubated with [u-14c]glucose. structural analysis of the compounds revealed that man9glcnac2 was the oligosaccharide transferred from dolichol-p-p derivatives to proteins in trypanosoma dionisii, trypanosoma conorhini, leptomonas samueli and herpetomonas samuelpessoai and man6glcnac2 in blastocrithidia culicis and leishmania adleri. in all cases, transiently glucosylated com ...19863083255
purification of metacyclic trypomastigotes of trypanosoma cruzi and trypanosoma dionisii from culture using an epimastigote-specific monoclonal antibody.monoclonal antibodies which react with culture forms of trypanosoma dionisii and trypanosoma cruzi were tested for their agglutination capacity. in these studies developmental stage specificity for the epimastigote form could be observed. this specificity meant it was possible to develop a quick and simple method to isolate cultured metacyclic trypomastigotes of t. dionisii and t. cruzi group 2. after agglutination of the epimastigote form with the monoclonal antibody dion 4.6 the purity of meta ...19873295861
characterization of plasma membrane polypeptides of trypanosoma from bats.cell surface proteins of trypanosoma dionisii, trypanosoma vespertilionis and trypanosoma sp. (m238) were radiodinated and their distribution both in the detergent-poor (dpp) and detergent-enriched phase (drp) was studied using a phase separation technique in triton x-114, as well as polyacrylamide gel electrophoresis in sodium dodecyl sulphate (sds-page). significant differences were observed in the proteins present in the drp when the three species of trypanosoma were compared. two major bands ...19892319946
identification of a novel large extrachromosomal dna (led) in the trypanosomatidae.we have identified a novel 75 kbp large extrachromosomal dna (led) which is stably maintained during developmental conversion of trypanosoma cruzi. it has a covalently closed circular conformation and is not derived from the kinetoplast network. in all t. cruzi strains analysed, led contains 18s rrna and spliced leader (sl) sequences. led from the t. cruzi y strain contains a minimum of 15 copies of the sl repeat arrayed in a head-to-tail configuration and 50 copies of a 196 bp repeat. led is al ...19921406269
biological and immunological studies on a low virulence isolate of the tulahuén strain of trypanosoma cruzi.reduced virulence for mice was characterized in an isolate (lv1) of a clone of the tulahuén strain of trypanosoma cruzi. lv1 caused long term chronic parasitemias which were measured for 140 days in both c3h/he and balb/c mice inoculated with 1 x 10(5) trypanosomes/mouse. in contrast to the acute and rapidly lethal tulahuén strain infections in both strains of mice, all of the animals survived the lv1 infections. sera of c3h/he mice infected with the tulahuén strain or lv1 isolate displayed simi ...19949747330
detection of an "epimastigote-like" intracellular stage of trypanosoma cruzi.monoclonal antibody (mab) dion 5.1b, derived from mice immunized with trypanosoma dionisii, recognizes a 72/76-kd surface glycoprotein specific to the epimastigote stage of t. dionisii and t. cruzi. none of the three other stages of the t. cruzi life cycle expresses any dion 5.1b-specific epitope. however, mab dion 5.1b labels an intracellular form with "epimastigote-like" morphology that appears to be late and transient in the intracellular cycle. this result suggests that the morphological sim ...19957501646
monohexosylceramides of trypanosoma dionisii.a detailed knowledge of the primary structure of neutral glycosphingolipids isolated and purified from trypanosoma dionisii has been elucidated using a combination of techniques--as column chromatography, hptlc and gc-ms together with fast atom bombardment spectrometry. the ceramide monohexoside fraction (cmh) contained both glucosyl- and galactosylceramides in a ratio of 1:1, sphingosine and as fatty acyl groups mainly c-24 saturated and 2-hydroxy fatty acids. a close similarity between trypano ...19968976606
phylogenetic diversity of bat trypanosomes of subgenus schizotrypanum based on multilocus enzyme electrophoresis, random amplified polymorphic dna, and cytochrome b nucleotide sequence analyses.trypanosome stocks isolated from bats (chiroptera) and belonging to the subgenus schizotrypanum were analyzed by multilocus enzyme electrophoresis (mlee) at 22 loci, random amplified polymorphic dna (rapd) with 14 primers and/or cytochrome b nucleotide sequence. bat trypanosomes belonged to the species trypanosoma cruzi marinkellei (10 stocks), trypanosoma dionisii (four stocks) and trypanosoma vespertilionis (three stocks). one t. rangeli stock and seven stocks of t. cruzi sensu stricto, the ag ...200312797982
molecular characterization of haemoparasites infecting bats (microchiroptera) in cornwall, uk.the presence of haemoparasites from the order piroplasmida and the genera bartonella and trypanosoma was assessed in the blood of 60 bats, belonging to 7 species, inhabiting sites across cornwall in southwest england. dna extracted from macerated heart tissue was incorporated into taxon-specific polymerase chain reactions (pcrs) and amplification products were sequenced as a means of identifying, or assigning an identity, to detected haemoparasites. a piroplasmida species was detected in 6 pipis ...200516174413
unique behavior of trypanosoma dionisii interacting with mammalian cells: invasion, intracellular growth, and nuclear localization.the phylogenetic proximity between trypanosoma cruzi and trypanosoma (schizotrypanum) dionisii suggests that these parasites might explore similar strategies to complete their life cycles. t. cruzi is the etiological agent of the life-threatening chagas' disease, whereas t. dionisii is a bat trypanosome and probably not capable of infecting humans. here we sought to compare mammalian cell invasion and intracellular traffic of both trypanosomes and determine the differences and similarities in th ...200919283898
mammalian cell invasion by closely related trypanosoma species t. dionisii and t. cruzi.protozoan parasites of the genus trypanosoma can infect virtually all mammalian species. within this genus, trypanosoma dionisii from bats and trypanosoma cruzi that causes chagas' disease, belonging to the subgenus schizotrypanum, can invade mammalian cells. the mechanisms of cell invasion by t. dionisii are poorly understood. to address that question, metacyclic trypomastigotes (mt) and human epithelial hela cells were used. similarly to genetically divergent t. cruzi strains g (tci) and cl (t ...201222079376
repertoire, genealogy and genomic organization of cruzipain and homologous genes in trypanosoma cruzi, t. cruzi-like and other trypanosome species.trypanosoma cruzi, the agent of chagas disease, is a complex of genetically diverse isolates highly phylogenetically related to t. cruzi-like species, trypanosoma cruzi marinkellei and trypanosoma dionisii, all sharing morphology of blood and culture forms and development within cells. however, they differ in hosts, vectors and pathogenicity: t. cruzi is a human pathogen infective to virtually all mammals whilst the other two species are non-pathogenic and bat restricted. previous studies sugges ...201222685565
phylogenetic analysis of bolivian bat trypanosomes of the subgenus schizotrypanum based on cytochrome b sequence and minicircle analyses.the aim of this study was to establish the phylogenetic relationships of trypanosomes present in blood samples of bolivian carollia bats. eighteen cloned stocks were isolated from 115 bats belonging to carollia perspicillata (phyllostomidae) from three amazonian areas of the chapare province of bolivia and studied by xenodiagnosis using the vectors rhodnius robustus and triatoma infestans (trypanosoma cruzi marenkellei) or haemoculture (trypanosoma dionisii). the pcr dna amplified was analyzed b ...201222590570
parasites reveal movement of bats between the new and old worlds.the global distribution of bat taxa indicates that the atlantic and pacific oceans are effective barriers to movement between the old and new worlds. for instance, one of the major suborders, yinpterochiroptera, has an exclusively old world distribution, and within the other, yangochiroptera, no species and only five genera are common to both. however, as bats are sometimes blown out to sea, and have colonised isolated islands, occasional natural movement between the new and old worlds does appe ...201222306822
isolation and phylogenetic relationships of bat trypanosomes from different biomes in mato grosso, the order chiroptera, more than 30 trypanosome species belonging to the subgenera herpetosoma, schizotrypanum, megatrypanum, and trypanozoon have been described. the species trypanosoma cruzi , trypanosoma cruzi marinkellei, and trypanosoma dionisii are the most common in bats and belong to the schizotrypanum subgenus. bats from 2 different biomes, pantanal and amazonia/cerrado in the state of mato grosso, brazil, were evaluated according to the presence of trypanosome parasites by means of h ...201323859496
tridimensional ultrastructure and glycolipid pattern studies of trypanosoma dionisii.trypanosoma (schizotrypanum) dionisii is a non-pathogenic bat trypanosome closely related to trypanosoma cruzi, the etiological agent of chaga's disease. both kinetoplastids present similar morphological stages and are able to infect mammalian cells in culture. in the present study we examined 3d ultrastructure aspects of the two species by serial sectioning epimastigote and trypomastigote forms, and identified common carbohydrate epitopes expressed in t. dionisii, t. cruzi and leishmania major. ...201323933185
survey of trypanosoma and leishmania in wild and domestic animals in an atlantic rainforest fragment and surroundings in the state of espírito santo, brazil.trypanosoma and leishmania infections affect wild and domestic animals and human populations. the growing process of deforestation and urbanization of atlantic rainforest areas has given rise to introduction of humans and domestic animals to the sylvatic cycles of trypanosoma and leishmania species. serological, parasitological, and molecular surveys among wild and domestic animals in the corrego do veado biological reserve, which is an atlantic rainforest fragment in the state of espírito santo ...201424897863
the diversity and expansion of the trans-sialidase gene family is a common feature in trypanosoma cruzi clade members.trans-sialidase (ts) is a polymorphic protein superfamily described in members of the protozoan genus trypanosoma. of the eight ts groups recently described, ts group i proteins (some of which have catalytic activity) are present in the distantly related trypanosoma brucei and trypanosoma cruzi phylogenetic clades, whereas other ts groups have only been described in some species belonging to the t. cruzi clade. in the present study we analyzed the repertoire, distribution and phylogenetic relati ...201626640033
trypanosome species, including trypanosoma cruzi, in sylvatic and peridomestic bats of texas, contrast to other mammalian reservoirs, many bat species migrate long-distances and have the potential to introduce exotic pathogens to new areas. bats have long been associated with blood-borne protozoal trypanosomes of the schizotrypanum subgenus, which includes the zoonotic parasite trypanosoma cruzi, agent of chagas disease. another member of the subgenus, trypanosoma dionisii, infects bats of europe and south america, and genetic similarities between strains from the two continents sugge ...201627647574
ecological scenario and trypanosoma cruzi dtu characterization of a fatal acute chagas disease case transmitted orally (espírito santo state, brazil).trypanosoma cruzi infection via oral route results in outbreaks or cases of acute chagas disease (acd) in different brazilian regions and poses a novel epidemiological scenario. in the espírito santo state (southeastern brazil), a fatal case of a patient with acd led us to investigate the enzootic scenario to avoid the development of new cases. at the studied locality, triatoma vitticeps exhibited high t. cruzi infection rates and frequently invaded residences.201627580853
small subunit ribosomal metabarcoding reveals extraordinary trypanosomatid diversity in brazilian bats.bats are a highly successful, globally dispersed order of mammals that occupy a wide array of ecological niches. they are also intensely parasitized and implicated in multiple viral, bacterial and parasitic zoonoses. trypanosomes are thought to be especially abundant and diverse in bats. in this study, we used 18s ribosomal rna metabarcoding to probe bat trypanosome diversity in unprecedented detail.201728727769
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