| [characterization of trypanosoma cruzi isolates, using restriction enzyme analysis of kinetoplast dna]. | | 1992 | 1357213 |
| glycolipid and protein profiles of normal and trypanosoma cruzi infected heart muscle cells. | using triton x-114, glycolipids and proteins were extracted from heart muscle cells (hmc) infected with trypanosoma cruzi clone dm28c and from uninfected hmc, and analysed by sds-page and high-performance thin-layer chromatography (hptlc). two major differences were observed: (a) two proteins with a molecular mass of 92 kda and 69 kda were present in the uninfected cells but absent from the infected cells and (b) a 70-90 kda protein band was detected only in parasitized cells. these differences ... | 1992 | 1359757 |
| effects of hydroquinones on intact trypanosoma cruzi epimastigotes. | 1. hydroquinones inhibited the culture growth of trypanosoma cruzi epimastigotes at concentrations lower than 1 mm. 2. hydroquinones inhibited the oxygen consumption on the intact trypanosoma cruzi cells. i50 values for hydroquinone, terbutylhydroquinone and 2,5-di-t-butylhydroquinone were 24.87 mm, 0.88 mm and 0.26 mm, respectively. t-butylhydroquinone and 2,5-di-t-butylhydroquinone had a michaelian type kinetic inhibition; hydroquinone also showed a michaelian type kinetic inhibition at low co ... | 1992 | 1360379 |
| isometric developed tension and histopathology of myocardium of chagasic mice. ii. | in a preceding paper we reported the evolution of chagasic cardiopathy in mice inoculated with low number of t. cruzi from 2 days to 75 days post-infection (p.i.). the present work analyzed the contractility, pharmacological response and histopathology of myocardium isolated from chronic chagasic mice from 90 days until 180 days. p.i. myocardium contractile force reached values similar to controls until 165 days p.i. from this to the end contractility was significantly lower. at 90 days p.i. ne ... | 1992 | 1364191 |
| entry of trypanosoma cruzi into eukaryotic cells. | trypanosoma cruzi invades a variety of mammalian cells by receptor-ligand interactions. in this review two t. cruzi carbohydrate-binding proteins, neuraminidase/trans-sialidase and penetrin, are discussed as possibly playing a role in parasite entry into mammalian cells. | 1992 | 1365537 |
| trypanosoma cruzi flagellar repetitive antigen expression by recombinant baculovirus: towards an improved diagnostic reagent for chagas' disease. | we constructed a recombinant baculovirus that expressed part of a trypanosoma cruzi flagellar repetitive antigen (fra). both cell- associated and secreted forms of recombinant fra were detected in cultures of virus-infected spodoptera frugiperda (sf9) cells. these forms show a complex pattern after polyacrylamide gel electrophoresis and western blot analysis using either an anti-fra rabbit serum or human chagasic sera. competitive western-blot experiments revealed that all bands react with the s ... | 1992 | 1369025 |
| american leishmania spp. and trypanosoma cruzi: galactosyl alpha(1-3) galactose epitope localization by colloidal gold immunocytochemistry and lectin cytochemistry. | patients with chagas' disease or different clinical forms of leishmaniasis (cutaneous or visceral) have elevated galactosyl alpha (1-3)galactose antibodies. using colloidal gold immunocytochemistry--monoclonal antibody gal-13 (specific for lipid-linked galactosyl alpha (1-3)galactose residues) and anti-nidogen antibodies and lectin cytochemistry (bandeiraea simplicifolia ib4), both techniques specific for demonstrating galactosyl alpha (1-3)galactose residues--we have found terminal disaccharide ... | 1992 | 1370418 |
| attachment of trypanosoma cruzi to host cells: a monoclonal antibody recognizes a trypomastigote stage-specific epitope on the gp 83 required for parasite attachment. | a set of monoclonal antibodies against the purified surface gp 83 of t. cruzi trypomastigotes was produced and the ability of these monoclonals to inhibit the attachment of trypomastigotes to heart myoblasts was investigated. western blots of solubilized trypomastigotes, epimastigotes or amastigotes probed with this set of monoclonal antibodies show that the gp 83 is present in invasive trypomastigotes, but not in non-invasive epimastigotes or amastigotes. one monoclonal antibody (mab 4a4) from ... | 1992 | 1370617 |
| identification and synthesis of a major conserved antigenic epitope of trypanosoma cruzi. | a gene sequence encoding an immunodominant protein with a repetitive epitope from the protozoan trypanosoma cruzi, the causative agent of chagas disease, was cloned and expressed. the identified 10-amino acid repeat is present within a high-molecular-weight trypomastigote antigen that appears specific to and conserved among t. cruzi isolates. more importantly, greater than 95% of t. cruzi infection sera, including both chronic and acute chagas disease, contained elevated levels of antibody to a ... | 1992 | 1371355 |
| identification of the gene(s) coding for the trans-sialidase of trypanosoma cruzi. | the gene(s) encoding the trypanosoma cruzi shed-acute-phase-antigen (sapa) has a 5' end encoding a region containing two totally and two partially conserved ser-x-asp-x-gly-x-thr-trp motifs which are present in bacterial neuraminidases, and a 3' end encoding tandemly repeated units of 12 amino acids. it is now reported that 54-87% of the total neuraminidase activity present in the parasite could be immunoprecipitated with polyclonal or monoclonal antibodies against the repeated amino acid units ... | 1992 | 1374711 |
| stage-specific expression and intracellular shedding of the cell surface trans-sialidase of trypanosoma cruzi. | we have used antibodies to the trypanosoma cruzi trans-sialidase and to its product, the host cell invasion-related ssp-3 epitope, to study the expression of the corresponding antigens during the intracellular development of the parasite and in the extracellular trypomastigotes. as soon as 2 h after host cell invasion, trans-sialidase was no longer detected, whereas the ssp-3 epitope was still present on intracellular parasites. the amastigotes which subsequently developed remained nonreactive w ... | 1992 | 1375197 |
| a trypanosoma cruzi membrane protein shares an epitope with a lymphocyte activation antigen and induces crossreactive antibodies. | chagas' disease results from the infection of the protozoan parasite trypanosoma cruzi and affects several million people in south america. several alterations of the immune response have been described in this disease, such as severe immunosuppression of both cellular and humoral responses and massive polyclonal stimulation with the generation of autoantibodies crossreacting with host cells and tissues. we have obtained monoclonal antibodies (mabs) from t. cruzi-infected mice that recognized a ... | 1992 | 1375261 |
| trypanosoma cruzi: enhanced alpha-macroglobulin levels correlate with the resistance of balb/cj mice to acute infection. | trypanosoma cruzi proteinases are very likely involved in host-cell invasion. physiological plasma-proteinase inhibitors from the macroglobulin (mg) family, among them alpha-2-macroglobulin (a2m), are found in tissues and in the plasma of mammals. by complexing to all classes of proteinases, mgs inhibit their action on high-molecular-weight substrates. in vitro studies have shown that a2m impairs t. cruzi proteases and, consequently, the parasite's ability to invade host cells and enhances the p ... | 1992 | 1375380 |
| isotype determination of anti-trypanosoma cruzi antibody in murine chagas' disease. | isotypic analysis of anti-parasite humoral responses of c57b1/6 and c3h (he) mice surviving acute trypanosoma cruzi infection showed that both mouse strains demonstrate igg1, igg2a, igg2b, and igm enzyme-linked immunosorbent assay titers from days 21 to 300 of infection. using the western blot technique to determine the antigen specificity of the isotypic responses, 100-day infected c3h mice showed strong igg1, igg2a, and igg2b responses to many antigens, whereas c57b1/6 mice showed weak respons ... | 1992 | 1375959 |
| the neuraminidases of trypanosoma cruzi and acanthamoeba castellanii are immunologically related. | we have recently reported the presence of neuraminidase (na) activity in acanthamoeba castellanii. we now show that the nas of t. cruzi and a. castellanii share cross-reactive determinants using tcn-2, a monoclonal antibody (mab) against the t. cruzi na and a mouse polyclonal ab (anti-tr) raised against a tandemly repeated dodecapeptide which contains the epitope recognized by tcn-2 (prioli et al., submitted). this cross-reactivity was demonstrated by the reaction of tcn-2 and anti-tr with a. ca ... | 1992 | 1376002 |
| cd5 b cells. potential role in the (auto)immune responses to trypanosoma cruzi infection. | | 1992 | 1376076 |
| 2-5a synthetase expression in mice infected with trypanosoma cruzi. | this study describes the production and action of interferon in mice infected with colombian and y strain t. cruzi. the production of interferon was monitored by an in vitro assay of plasma and extract of spleen, lung and heart for interferon activity. the action of interferon in mice was assessed by measuring an interferon-mediated enzyme activity, 2-5a synthetase. infected mice (strain balb/c) were sacrificed at different time intervals, and the level of this enzyme was measured in extracts of ... | 1992 | 1376891 |
| mapping of a visceral leishmaniasis-specific immunodominant b-cell epitope of leishmania donovani hsp70. | we have shown that a member of the 70-kda heat shock protein (hsp70) family is a major target of the humoral immune response during leishmania donovani infection. a recombinant fusion protein was recognized by sera from 92% (35 of 38) of patients with visceral leishmaniasis, including representatives from each of the major regions where it is endemic. serological analysis of recombinant hsp70, expressed by a series of deletion constructs, identified the carboxy-terminal region as the immunodomin ... | 1992 | 1377180 |
| cloning and expression of trypanosoma cruzi ribosomal protein p0 and epitope analysis of anti-p0 autoantibodies in chagas' disease patients. | chagas' disease, caused by the intracellular protozoan parasite trypanosoma cruzi, is a major cause of heart failure in endemic areas. antigenic mimicry by t. cruzi antigens sharing epitopes with host macromolecules has been implicated in the pathogenesis which is thought to have a significant autoimmune component. we report herein on the cloning and characterization of a full-length cdna from a t. cruzi expression library encoding a protein, tcp0, that is homologous to the human 38-kd ribosomal ... | 1992 | 1377223 |
| mapping of a b-cell epitope present in the neuraminidase of trypanosoma cruzi. | we have previously shown that a polyclonal (rabbit anti-tcna) and a mouse monoclonal antibody (tcn-2) against the neuraminidase of trypanosoma cruzi (tcna) inhibit enzyme activity, immunoprecipitate active enzyme, enhance in vitro infection, and identify a subpopulation of extracellular trypomastigotes. we now report on the identification of a synthetic peptide that contains the epitope recognized by these antibodies. the synthetic peptide (tr) is a dodecamer (d-s-s-a-h-g-t-p-s-t-p-a) deduced fr ... | 1992 | 1378212 |
| antiribosomal antibodies in systemic lupus erythematosus. | ara occur in approximately 10% of randomly selected sle patients but in up to 40% of patients with active disease. anti-p antibodies appear to be a highly specific diagnostic marker for sle because they are rarely detected in other multisystem autoimmune disorders. ara are most frequently directed against the p proteins, and the shared conserved c-terminus of the p proteins is immunodominant in almost all sera tested. anti-p antibodies increase in titer in patients with active disease and have b ... | 1992 | 1378226 |
| cloning and sequencing of a 24-kda trypanosoma cruzi specific antigen released in association with membrane vesicles and defined by a monoclonal antibody. | in the present study we have used the tcr7 monoclonal antibody (mab) previously characterized as directed against trypanosoma cruzi 24-25-kda specific antigens, both are immunogenic in man and during experimental t cruzi infections. we have demonstrated that mab tcr7 was able to recognize two in vitro translation products of molecular weights of 24 and 25 kda. this suggested the holoproteic nature of these two related antigens bearing at least a common epitope and allowed us to use tcr7 for an i ... | 1992 | 1381253 |
| induction of a pharmacologically active clonotypic b cell response directed to an immunogenic region of the human beta 2-adrenergic receptor. | it has been reported that autoantibodies against the beta 2-adrenergic receptors are involved in the pathology of allergic disorders and of chagas' disease. therefore, the immune response against a peptide (h26q) corresponding to the putative second extracellular loop of the human beta 2-adrenergic receptor, which could be a target for autoantibody attack, was analysed in view of its possible immunogenicity. the free peptide induced a t cell-mediated humoral response in the context of three diff ... | 1992 | 1381303 |
| characterization of chilean, bolivian, and argentinian trypanosoma cruzi populations by restriction endonuclease and isoenzyme analysis. | ninety-one chilean, 15 bolivian, and 9 argentinian trypanosoma cruzi stocks, isolated from various hosts and vectors, were characterized by schizodeme analysis with ecori and mspi endonucleases. the three major similar pattern groups that emerged from this sample correlated with results of isoenzyme analysis. this result confirms previous work and supports the hypothesis of the clonal structure of natural populations of t. cruzi, fully defined at the level of isoenzyme analysis, quantitative kin ... | 1992 | 1381320 |
| decay accelerating factor (cd55). | | 1992 | 1385047 |
| characterization of the c-terminal region of a trypanosoma cruzi 38-kda ribosomal p0 protein that does not react with lupus anti-p autoantibodies. | a trypanosoma cruzi cdna lambda gt11 recombinant, c-p0, encoding the carboxyterminus of a highly antigenic ribosomal p protein, was isolated. sequence comparisons and immunological evidence allowed its identification as the c-terminal region of the t. cruzi 38-kda ribosomal p0 protein. this recombinant failed to react with systemic lupus erythematosus (sle) anti-p antibodies. the t. cruzi ribosomal p0 protein is the first reported eukaryotic ribosomal p protein presenting this immunological prop ... | 1992 | 1385317 |
| metabolic labelling and partial characterisation of a sulfoglycolipid in trypanosoma cruzi trypomastigotes. | | 1992 | 1394325 |
| protozoan infections and hiv-1 infection: a review. | reactivation of latent infection is the principal mechanism relating toxoplasma gondii and pneumocystis carinii to hiv. less common is reactivation in leishmania donovani, trypanosoma cruzi, and microsporidian infections. an impaired primary immune response occurs in all these infections, and also with cryptosporidium and isospora belli. association of hiv infection with gut parasites including giardia lamblia and entamoeba histolytica, and also with trichomonas vaginalis infection is likely to ... | 1992 | 1396192 |
| only some members of a gene family in trypanosoma cruzi encode proteins that express both trans-sialidase and neuraminidase activities. | trypomastigotes, the blood stage form of the human parasite trypanosoma cruzi, contain an enzyme on their surface, trans-sialidase, which catalyses the transfer of sialic acid from host glycoconjugates to acceptors on its own cell surface. at least a subset of the sialic acid-bearing acceptor molecules are involved in parasite invasion of host cells, an essential step in the life cycle of the parasite. another trypomastigote surface enzyme that affects host cell invasion is neuraminidase and rec ... | 1992 | 1396577 |
| the microbicidal activity of interferon-gamma-treated macrophages against trypanosoma cruzi involves an l-arginine-dependent, nitrogen oxide-mediated mechanism inhibitable by interleukin-10 and transforming growth factor-beta. | the present study was carried out to determine the effector mechanism of anti-trypanosoma cruzi activity by interferon (ifn)-gamma plus lipopolysaccharide (lps)-treated macrophages. a macrophage cell line (ic-21) that failed to mount an appreciable oxidative burst was nevertheless found able to control t. cruzi growth after exposure to ifn-gamma alone or ifn-gamma plus lps. moreover, microbicidal functions of both inflammatory macrophages and ic-21 against t. cruzi was found to be inhibited in t ... | 1992 | 1396957 |
| characterization of a multi-copy gene for a major stage-specific cysteine proteinase of leishmania mexicana. | lmcpb, a gene from leishmania mexicana that encodes a major cysteine proteinase in the parasite, has been cloned and sequenced. lmcpb is related more to cysteine proteinases from trypanosoma brucei and trypanosoma cruzi than to a previously characterized cysteine proteinase, lmcpa, of l. mexicana. it contains a long c-terminal extension characteristic of similar enzymes of t. brucei and t. cruzi. the gene is multi-copy and tandemly arranged. lmcpb rna levels are developmentally regulated with st ... | 1992 | 1397299 |
| aerobic fermentation of glucose by trypanosomatids. | the consumption of glucose by trypanosomatid protozoa such as trypanosoma brucei, trypanosoma cruzi, leishmania spp., and crithidia spp. is characterized by the excretion of reduced products such as succinate, pyruvate, ethanol, l-alanine, or lactate (depending on the species) not only in anaerobiosis, but also under aerobic conditions. the "aerobic fermentation" of glucose is accompanied by a complete lack, or even a reversal, of the pasteur effect. this peculiar catabolism is mediated by a so- ... | 1992 | 1397837 |
| modulation of thymocyte subsets during acute and chronic phases of experimental trypanosoma cruzi infection. | several observations have demonstrated the importance of t-cell-mediated mechanisms in experimental chagas' disease. in previous studies, we have shown that mice acutely infected by trypanosoma cruzi develop a progressive thymic atrophy with severe alterations in the lymphoid compartment. in this report we performed a kinetic analysis of the murine thymic lymphocytes comparing acute and chronic phases of infection. at the chronic phase, we observed that total thymocyte numbers returned to age-ma ... | 1992 | 1398769 |
| evidence for two distinct major protein components, par 1 and par 2, in the paraflagellar rod of trypanosoma cruzi. complete nucleotide sequence of par. | the previously identified major protein components of the paraflagellar rod in trypanosoma cruzi, par 1 and par 2, were analyzed to determine if they are distinct proteins or different conformations of a single polypeptide as has been suggested for other trypanosomatids. amino acid sequence analysis showed par 1 and par 2 to be two distinct polypeptides. antibodies specific against either par 1 or par 2 were shown to each react with a distinct band in western blots of paraflagellar isolates of t ... | 1992 | 1400477 |
| effect of azadirachtin on the development of trypanosoma cruzi in different species of triatomine insect vectors: long-term and comparative studies. | studies were carried out on the effects of azadirachtin on the course of trypanosoma cruzi infection in the gut of different triatomine vector species. in rhodinus prolixus the development of t. cruzi clone dm28c decreased in a dose-dependent manner, and the ed50 of this inhibitory effect was 0.25 microgram azadirachtin/ml bloodmeal. using this insect, we conducted a long-term experiment which showed that azadirachtin (1.0 microgram/ml bloodmeal) completely blocks the development of t. cruzi eve ... | 1992 | 1401990 |
| trypanosoma cruzi infection of bsc-1 fibroblast cells causes cytoskeletal disruption and changes in intracellular calcium levels. | the disruption of vimentin and actin filaments of host bsc-1 fibroblast cells by trypanosoma cruzi was investigated using a mouse monoclonal anti-vimentin antibody and rhodamine phalloidin, respectively. indirect immunofluorescence microscopy demonstrated that infection of bsc-1 cells by t. cruzi caused disruption of both cytoskeletal components. the disruption was greater as infection progressed. mechanisms other than mechanical ones may play a role in the disruption since disrupted cytoskeleta ... | 1992 | 1403981 |
| 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 ... | 1992 | 1406269 |
| pcr amplification of mini-exon genes differentiates trypanosoma cruzi from trypanosoma rangeli. | synthetic oligonucleotides corresponding to a conserved 22 nucleotide sequence within the tandemly repeated mini-exon gene have been used to amplify a single gene-containing repeat from trypanosoma cruzi and trypanosoma rangeli, two morphologically similar organisms with overlapping hosts and geographical distribution but different pathogenicity in humans. the t. cruzi repeat is 582 nucleotides long and the t. rangeli repeat is 858 nucleotides. the two organisms may therefore be distinguished pr ... | 1992 | 1406732 |
| inhibitory effect of piquerol a on the growth of epimastigotes of trypanosoma cruzi. | | 1992 | 1409986 |
| correlation of antibodies to ribosomal p protein with psychosis in patients with systemic lupus erythematosus. | ninety one japanese patients with systemic lupus erythematosus (sle) were studied to determine the clinical significance of antibodies to ribosomal p protein (anti-p). anti-p was detected by western blotting in 38 of 91 patients (42%). clinical symptoms of sle were compared between patients with and without anti-p. the occurrence of lupus psychosis was significantly higher in patients with anti-p than in those without anti-p (9/38 v 1/53). no significant association was found between anti-p and ... | 1992 | 1417136 |
| antiribosomal p antibodies and lupus psychosis. | | 1992 | 1417156 |
| molecular aspects of trypanosoma cruzi interaction with host cell and parasite differentiation mechanisms. | | 1992 | 1417166 |
| infectivity to the vector triatoma infestans of dogs infected with trypanosoma cruzi in north-west argentina. | the influence of reinfections on the infectivity to triatoma infestans of dogs seropositive to trypanosoma cruzi was investigated in amamá, north-west argentina, before (1984) and after (1986-1987) elimination of domestic bugs with residual insecticides in 1985. infectivity was quantified by the percentage of infected bugs in each xenodiagnosis of a seropositive dog, i.e. the infective force (if). exposure to reinfection was represented by the domiciliary density of infected bugs and by an index ... | 1992 | 1417201 |
| synthesis and antiprotozoal properties of 1,2,6-thiadiazine 1,1-dioxide derivatives. | the synthesis and spectroscopical data of 1,2,6-thiadiazine 1,1-dioxides, designed as antiprotozoal agents, are reported. the in vitro trichomonacidal and trypanocidal activities of new compounds and their precursors were evaluated against trichomonas vaginalis and trypanosoma cruzi. the chemoprophylactic activity on mice treated with blood infected with t. cruzi and their mortality percentage were tested. compounds 2 and 8b show a higher chemoprophylactic activity and lower mortality percentage ... | 1992 | 1417459 |
| purification and characterization of a new 120 kda alkaline proteinase of trypanosoma cruzi. | a new alkaline proteinase activity was identified in cell-free extracts of trypanosoma cruzi epimastigotes on the basis of its ability to hydrolyze the fluorogenic substrate n-z-gly-gly-arg-amc. the optimal activity was at ph 8.0. after a three step-chromatography procedure using two anionic columns (deae-sepharose and mono q) and a chromatofocusing column (mono p), the proteolytic activity was associated with a single 120 kda protein and was called tc 120 proteinase. the molecular mass of the p ... | 1992 | 1417823 |
| differential regulation of putrescine uptake in trypanosoma cruzi and other trypanosomatids. | putrescine uptake in trypanosoma cruzi epimastigotes is 10 to 50-fold higher than in leishmania mexicana or crithidia fasciculata. polyamine transport in all these trypanosomatids is an energy-dependent process strongly inhibited by the presence of 2,4-dinitrophenol or kcn. putrescine uptake in t. cruzi and l. mexicana was markedly decreased by the proton ionophore carbonylcyanide m-chlorophenylhydrazone but it was not affected by ouabain, a na(+)-k+ pump inhibitor. the depletion of intracellula ... | 1992 | 1417835 |
| changes in proteolytic activity during the growth of trypanosoma cruzi epimastigotes. | the proteolytic pattern of trypanosoma cruzi epimastigotes was studied using electrophoresis in gelatin containing sds polyacrylamide gels. under conditions that represent a nutritional stress such as the depletion of glucose in an axenic medium the results obtained showed a significant increase in the activity of two proteases of m(r) = 50,000 and m(r) = 60,000 as well as the appearance of higher molecular weight bands during the transition from log to stationary phase parasites. the use of dif ... | 1992 | 1417896 |
| fluorescence of chromatin dna by an oxazolium scintillator. | aqueous solutions of a yellow and highly fluorescent derivative from dimethyl-popop, obtained by treating a chloroform solution of this oxazole scintillator with dimethylsulfate, induce a strong blue-green or yellow-green fluorescence in chromatin dna under ultraviolet (365 nm) or violet-blue (436 nm) excitation, respectively. it is suggested that this new and selective fluorescence reaction could originate from binding of the oxazolium derivative into the minor groove of dna. | 1992 | 1418244 |
| studies on vectors of trypanosoma cruzi in trinidad, west indies. | studies on vectors of trypanosoma cruzi chagas were conducted during 1982-85 as part of an investigation on the epidemiological status of american trypanosomiasis in trinidad, west indies. a total of 148 reduviid bugs were collected from caves, armadillo nests and at light traps, comprising four sylvatic species and totalling 120 panstrongylus geniculatus (latreille), two p. rufotuberculatus (champion), twelve rhodnius pictipes stal and fourteen eratyrus mucronatus stal. a significantly higher l ... | 1992 | 1421480 |
| chagas' disease. | chagas' disease, caused by trypanosoma cruzi, is an important cause of morbidity in many countries in latin america. the important modes of transmission are by the bite of the reduviid bug and blood transfusion. the organism exists in three morphological forms: trypomastigotes, amastigotes, and epimastigotes. the mechanism of transformation and differentiation is currently being explored, and signal transduction pathways of the parasites may be involved in this process. parasite adherence to and ... | 1992 | 1423218 |
| sapa/trans-sialidase and cruzipain: two antigens from trypanosoma cruzi contain immunodominant but enzymatically inactive domains. | trypanosoma cruzi, the parasitic protozoan that causes the american trypanosomiasis, or chagas disease, contains a number of antigenic molecules, some of which have tandems of amino acid repeats. one of these molecules, sapa (shed acute phase antigen), contains a so-far unique trans-sialidase activity that is essential for penetration of the parasite into mammalian cells. the enzyme consists of two different domains, one presumably enzymatic, which contains four copies of an amino acid motif con ... | 1992 | 1426764 |
| suppression by trypanosoma cruzi of t-cell receptor expression by activated human lymphocytes. | the immunosuppression that develops during chagas' disease and african sleeping sickness is thought to facilitate survival of the causative agents in their mammalian hosts. whereas a number of manifestations of immunosuppression manifested during the course of these diseases has been reported in patients and animals, the mechanisms by which they are induced remain obscure. an in vitro system in which phytohaemagglutinin (pha)-stimulated human peripheral blood mononuclear (pbmc) were co-cultured ... | 1992 | 1427979 |
| seropositivity to trypanosoma cruzi in blood donors in santa cruz, bolivia. | | 1992 | 1431271 |
| biological and chemical studies of pera benensis, a bolivian plant used in folk medicine as a treatment of cutaneous leishmaniasis. | the stem barks of pera benensis are employed by the chimane indians in the bolivian amazonia as treatment of cutaneous leishmaniasis caused by the protozoan leishmania braziliensis. the chloroform extracts containing quinones were found active against the promastigote forms of leishmania and the epimastigote forms of trypanosoma cruzi at 10 micrograms ml-1. the activity guided fractionation of the extract by chromatography afforded active compounds. their structures were elucidated, by spectral ... | 1992 | 1434690 |
| dna fingerprinting of trypanosoma cruzi: a new tool for characterization of strains and clones. | using nonradioactive hybridization, the human multilocus probe 33.15 was shown to recognize multiple minisatellite regions in nuclear dna from trypanosoma cruzi, producing complex banding patterns on southern blots, typical of dna fingerprints. the dna fingerprints were stable and were capable of identifying different strains of the parasite. individual clones of the y strain showed different banding patterns, demonstrating that the strain is heterogeneous. in general, the sensitivity and specif ... | 1992 | 1435866 |
| nucleotide sequence of a representative member of a trypanosoma cruzi dispersed gene family. | | 1992 | 1435871 |
| [cloning of kdna minicircles in different species of leishmania and its use as probes for diagnosis]. | the present study describes the cloning procedure for fragments of kinetoplast dna minicircles from different leishmania species and its use for detecting the presence of these parasites. our methodology was as follow: the dna of the kinetoplast from leishmania mexicana amazonensis and leishmania braziliensis panamensis was extracted, purified and digested with the enzyme dra i. these fragments were cloned in the site for hinc ii in the plasmid pks. e. coli was the bacterial strain used for tran ... | 1992 | 1439001 |
| isolation of trypanosoma cruzi from blood by histopaque and continuous percoll gradient centrifugations. | separation of the blood forms of trypanosomes from the blood of infected animals is difficult, especially in the case of trypanosoma cruzi y strain. two procedures to isolate the y strain blood forms of t. cruzi using polyvinyl pyrrolidone-coated silica (percoll) and histopaque are reported in this study. the recovery rates of parasites were 16 +/- 5 and 68 +/- 16%, respectively. the parasites isolated by these methods presented normal motility and morphology and were infective to albino mice wi ... | 1992 | 1444354 |
| a simple method for detection of monoclonal isotypes. | a simple rapid method of enzyme labeled anti-isotype assay (elia) for detection of monoclonal isotype on hybridoma cells is proposed. this alternative method was first carried out on hybridoma cell lines 147c11 and 257c11 produced against trypanosoma cruzi and male accessory secretion of panstrongylus megistus, respectively. the monoclonal antibodies produced by these hybridoma were characterized by this method as igm (147c11) and igg1 (257c23) isotypes, allowing evaluation of isotype without ha ... | 1992 | 1444357 |
| characterization of a gi-protein from trypanosoma cruzi epimastigote membranes. | a guanosine 5'-[gamma-[35s]thio]triphosphate-binding activity was detergent-extracted from trypanosoma cruzi membranes. this binding activity was co-eluted from gel-filtration columns with a factor which, in a heterologous reconstitution system, blocks glucagon stimulation of adenylate cyclase activity in liver membranes. adp-ribosylation of these membranes by pertussis toxin eliminated this blocking capacity. incubation of t. cruzi membranes with activated pertussis toxin and [adenylate-32p]nad ... | 1992 | 1445203 |
| structural characterization of a novel class of glycophosphosphingolipids from the protozoan leptomonas samueli. | aqueous phenol extraction of the lower trypanosomatid leptomonas samueli released into the aqueous layer a chloroform/methanol/water-soluble glycophosphosphingolipid fraction. alkaline degradation and purification by gel filtration chromatography resulted in a tetrasaccharide (phosphatidylinositol (pi)-oligosaccharide a), and a pentasaccharide (pi-oligosaccharide b), each containing 2 mol of 2-aminoethylphosphonate and 1 mol of phosphate. nuclear magnetic resonance spectroscopy and fast atom bom ... | 1992 | 1447177 |
| the epidemiology of chagas' disease in a hyperendemic area of cochabamba, bolivia: a clinical study including electrocardiography, seroreactivity to trypanosoma cruzi, xenodiagnosis, and domiciliary triatomine distribution. | a clinicoepidemiologic survey of chagas' disease was conducted in the remote rural village of tabacal in southcentral cochabamba, bolivia. in june and july 1988, we interviewed and examined 153 of 160 villagers > five years old for signs and symptoms of chagas' disease. all participants had electrocardiograms (ekgs) and serologic analysis performed, and 20 villagers underwent xenodiagnosis. all 40 houses in the village were examined for triatomes, and house construction materials and defects wer ... | 1992 | 1449194 |
| polymerase chain reaction-based detection of trypanosoma cruzi dna in serum. | dnas prepared from chagasic patients' sera were amplified by the polymerase chain reaction using oligonucleotide primers which anneal specifically to a highly repetitive sequence of trypanosoma cruzi nuclear dna. samples from both acutely and chronically infected patients yielded positive results by this method. no significant difference was observed when either whole blood or serum samples of the patients were used. these results indicate that serum instead of whole-blood samples could be used ... | 1992 | 1452655 |
| nerve lesions induced by macrophage activation. | the neuropathies associated with infectious processes, including leprosy, retroviral infections and chagas' disease, represent the largest group of neuropathies in the world. segmental demyelination and axonal degeneration of nerve fibres are associated with inflammatory infiltrates which contain a large number of mononuclear phagocytes. in order to learn more about the role played by macrophage activation in the nerve lesions observed in inflammatory neuropathies, we have performed a morphologi ... | 1992 | 1455050 |
| a comparative study of four serological methods for diagnosis of acute and chronic chagas' disease in brazilian patients. | complement fixation (cf), indirect immunofluorescence (ifat), latex agglutination (la) and the enzyme-linked immunosorbent assay (elisa) were applied to assess the diagnostic value of antibody determination in brazilian patients with acute or chronic chagas' disease. patients with various forms of leishmaniasis and healthy individuals from the endemic region were used as specificity controls. whereas la, ifat and elisa identified 81% of acutely ill patients, cf had no diagnostic potential in thi ... | 1992 | 1455524 |
| the effect of plastering in a house persistently infested with triatoma infestans (klug) 1934. | the replastering of a house in mambai-goias, brazil, as a measure to wall-in triatoma infestans, is briefly described. unfortunately, because the houseowner would not cooperate the roof tiles were not improved and eventually t. infestans reappeared at this site. a brief discussion follows of some aspects of house improvement in the vigilance phase of a chagas disease control programme. t. infestans appeared in the house described 51 and 258 days after the replastering. | 1992 | 1460702 |
| chagas disease: epidemiology and prospects for interruption of transmission in the americas. | american trypanosomiasis, or chagas disease, is a parasitic disease caused by the haemoflagellate protozoa, trypanosoma cruzi. the human infection occurs only in the americas, where it is widely distributed in the periurban and rural areas of tropical and subtropical countries, from mexico to argentina and chile. it is transmitted to man and other mammals mainly through insects, the triatomine bugs. as an enzootic disease, it extends from approximately latitude 42.5 degrees n (northern californi ... | 1992 | 1462661 |
| surveillance of trypanosoma cruzi transmission by serological screening of schoolchildren. | the seroprevalence of trypanosoma cruzi infection among children is a sensitive indicator for assessing the effectiveness of programmes for control of chagas disease. in this study we report the result of a cross-sectional serological survey carried out among schoolchildren living in a poor rural area in central brazil. eluates of blood collected on filter-paper were tested for anti-t. cruzi antibodies using immunofluorescence, haemagglutination, and enzyme-linked immunosorbent assays. the overa ... | 1992 | 1464149 |
| chagas' disease and kidney transplantation--follow-up of nine patients for 11 years. | | 1992 | 1466068 |
| hmg-like chromosomal proteins in trypanosoma cruzi. | hmg-like chromosomal proteins from trypanosoma cruzi were studied. four hmg-like proteins, designated hmg a, hmg-b, hmg-c, and hmg-e, were isolated and found to have molecular weights of 35.5 kd, 27.5 kd, 21.8 kd and 10.4 kd, respectively. immunological relatedness was demonstrated between the mammalian hmg 1,2 and the hmg-a and hmg-b from t. cruzi. the relative amounts of hmg-c and hmg-e proteins vary in t. cruzi depending to the proliferative stage of the cells. hmg-e protein is increased in p ... | 1992 | 1469064 |
| resialylation of sialidase-treated sheep and human erythrocytes by trypanosoma cruzi trans-sialidase: restoration of complement resistance of desialylated sheep erythrocytes. | trypanosoma cruzi trans-sialidase (ts) is a recently described enzyme which transfers alpha(2-3)-linked sialic acid from host-derived sialylated glycoconjugates to parasite surface molecules [schenkman et al. (1991) cell, 65, 1117]. we report here on the ability of ts to transfer sialic acid from donor sialyl-alpha(2-3)lactose to sialidase-treated sheep and human erythrocytes. up to approximately 50% resialylation of both desialylated red cells could be attained. resialylation of desialylated sh ... | 1992 | 1472761 |
| identification and characterization of an alpha-mannosidase from trypanosoma cruzi. | in this report we describe the first purification and characterization of the acid alpha-mannosidase from the human parasite trypanosoma cruzi. the purified enzyme exhibited a native mol. wt of 240,000 da and is apparently composed of four identical subunits of mol. wt 58,000 da. each of the four subunits contains one n-linked high-mannose-type oligosaccharide. the alpha-mannosidase exhibited a ph optimum of 3.5 and a pi of 5.9. this low ph optimum and the ability of swainsonine to inhibit its a ... | 1992 | 1472763 |
| lysosome recruitment and fusion are early events required for trypanosome invasion of mammalian cells. | trypanosoma cruzi invades most nucleated cells by a mechanism distinct from classical phagocytosis. although parasites enter at the lysosome-poor peripheral cell margins, lysosomal markers are immediately incorporated into the parasitophorous vacuole. no accumulation of polymerized actin was detected around recently internalized parasites, and disruption of microfilaments significantly facilitated invasion. lysosomes were observed to aggregate at the sites of trypanosome attachment and to fuse w ... | 1992 | 1473148 |
| sequence homology and absence of mrna defines a possible pseudogene member of the trypanosoma cruzi gp85/sialidase multigene family. | a genomic clone, ptt21, containing dna apparently transcribed specifically in trypanosoma cruzi trypomastigotes, was obtained by differentially screening a genomic library with trypomastigote and epimastigote cdna. this 3444-bp clone contained open reading frames at each end, separated by a 1.8-kb non-coding region. the translated polypeptide from the 3' open reading frame (orf2) of 1037 bp had 25-30% identity with 5 recently published t. cruzi gp85/sialidase sequences, and 20-25% identity with ... | 1992 | 1474990 |
| high-affinity calcium-stimulated, magnesium-dependent adenosine triphosphatase in trypanosoma cruzi. | 1. a high-affinity (ca2+ + mg2+)-atpase and a low-affinity mg(2+)-atpase were identified in the 105,000 g fraction from epimastigote forms of trypanosoma cruzi, the agent of chagas' disease (tulahuen strain). 2. activities were conserved after enzyme solubilization with deoxycholate. 3. the ca(2+)-stimulated atpase activity was (a) lower than that of the mg(2+)-atpase; (b) inhibited by p-chloromercurobenzoate and orthovanadate and (c) insensitive to oligomycin. 4. optimal stimulation by ca2+ was ... | 1992 | 1478071 |
| on the post-translational modifications at the c-terminal domain of the major cysteine proteinase (cruzipain) from trypanosoma cruzi. | cruzipain, the major cysteine proteinase from trypanosoma cruzi, has a 130 amino acid-long c-terminal domain, which, although microheterogeneous in sds-page, has a single n-terminal amino acid sequence. most of the thr residues present at the beginning of this sequence are modified; the nature of this modification is still unknown, but o-glycosylation and phosphorylation seem both to be absent. the only potential site for n-glycosylation (asn 254) is glycosylated in vivo. most of the eight cys r ... | 1992 | 1478474 |
| the life cycle of trypanosoma cruzi under axenic conditions. | the complete life cycle of trypanosoma cruzi under germfree (gf) conditions was achieved. the reduvidae insects dipetalogaster maximus, reared under axenic conditions were infected with trypanosoma cruzi, strain cl, by feeding on gf infected mice. axenic trypomastigotes from macerated gnotobiotic insects were used to infect gf and conventional (cv) mice by intraperitoneal, ocular, and oral routes. infection, followed by blood parasitemia, was obtained in almost all the cases. however, chagas' di ... | 1992 | 1479302 |
| temperature-dependent substrate inhibition of the cysteine proteinase (gp57/51) from trypanosoma cruzi. | | 1992 | 1484555 |
| intracellular digestion of endocytosed proteins as a source of amino acids for protein synthesis in trypanosoma cruzi. | | 1992 | 1485352 |
| energy metabolism in trypanosoma cruzi. | | 1992 | 1485353 |
| differential cardiac histopathology in inbred mouse strains chronically infected with trypanosoma cruzi. | seven inbred mouse strains were examined for the presence of chronic chagas' cardiomyopathy in postacute trypanosoma cruzi infection. dba/1, dba/2, balb/c, b10.t (6r), b10.q, b10.d2, and b6 mice were infected for 100 days with the brazil strain of t. cruzi. standard histologic examination of cardiac tissue from these mice revealed the following relationship among the different strains based on the severity of observed inflammation (myocarditis): balb/c, dba/1, and dba/2 were the most inflamed; b ... | 1992 | 1491299 |
| resistance of trypanosoma cruzi to blood clearance induced by acute-phase immune mouse serum. | to investigate functional changes in trypanosoma cruzi parasites induced during their interaction with the vertebrate host, we compared the blood clearance profiles of blood forms isolated from infected normal mice (reg-tc) or from infected mice immunodepressed after treatment with cyclophosphamide (cy-tc). parasite blood numbers were measured at various time intervals in animals injected intravenously (i.v.) with 1-2 x 10(6) t. cruzi of either isolate. in the absence of added immune sera (spont ... | 1992 | 1491301 |
| ultrastructural detection in vitro of wga-, rca i-, and con a-binding sites involved in the invasion of heart muscle cells by trypanosoma cruzi. | the presence of carbohydrate residues in the plasma membrane of normal and trypanosoma cruzi-infected heart muscle cells was investigated cytochemically using ruthenium red, lanthanum nitrate, periodic acid-schiff/thiocarbohydrazide/silver, and gold- and ferritin-lectin complexes. the study combined conventional electron microscopy with the new analytical technique of electron spectroscopic imaging (esi). galactosyl, mannosyl, and sialyl residues were detected in regions of host-cell plasma memb ... | 1992 | 1495918 |
| expression of the eukaryotic trypanosoma cruzi cra gene in yersinia enterocolitica and induction of an immune response against cra in mice. | the 70-kb plasmid pyv of yersinia enterocolitica directs the secretion of a set of proteins, called yops, that are produced during infection of humans and animals. trypanosoma cruzi, the agent of american trypanosomiasis, synthesizes a cytoplasmic protein termed cra that is considered to be t. cruzi specific. to produce cra in y. enterocolitica, we constructed a hybrid yope-cra gene that we integrated into plasmid pyv by homologous recombination. recombinant y. enterocolitica produced a chimeric ... | 1992 | 1500192 |
| interleukin-2 receptors in experimental chagas' disease. | mammals infected with the protozoan parasite trypanosoma cruzi develop suppressed cellular and humoral immune responses. this immunosuppression has been correlated with reduced t-cell responses involving deficient interleukin-2 (il-2) production and is apparently mediated primarily by suppressor macrophages. various forms of immunosuppression in other systems have been associated with increased levels of soluble il-2 receptors (sil-2r), and in the present study levels of sil-2r in the sera of t. ... | 1992 | 1500197 |
| identification of a large pre-lysosomal compartment in the pathogenic protozoon trypanosoma cruzi. | epimastigote forms of the pathogenic parasite trypanosoma cruzi were used to study the endocytic process in a protozoon. these elongated unicellular organisms are highly polarized cells: endocytosis occurs only at the anterior region through the cytostome and the flagellar pocket membrane, areas of the plasma membrane where the cell cytoskeleton, formed by sub-pellicular microtubules, is absent. when the cells were incubated at 4 degrees c or 28 degrees c with gold-labeled transferrin, fixed and ... | 1992 | 1500438 |
| cytokine gene expression of endothelial cells infected with trypanosoma cruzi. | coronary microvascular spasm and platelet hyperreactivity have been implicated in the pathogenesis of chagas' cardiomyopathy. to clarify further the role of the microvasculature in this disease, alterations in cytokine gene expression due to trypanosoma cruzi infection of human umbilical vein endothelial cells were examined. northern blot analysis of total rna from endothelial cells demonstrated that interleukin (il)-1 beta, il-6, and colony-stimulating factor 1 (csf-1) mrna expression was absen ... | 1992 | 1500742 |
| desialylation of lysosomal membrane glycoproteins by trypanosoma cruzi: a role for the surface neuraminidase in facilitating parasite entry into the host cell cytoplasm. | trypanosoma cruzi enters host cells via formation of an acidic vacuole which is subsequently disrupted, allowing the parasite access to the cytoplasm. we show that in an acid environment, release of the parasite surface neuraminidase is enhanced, and this release is likely mediated by a phosphatidylinositol-specific phospholipase c (piplc), since antibodies to a carbohydrate epitope (crd) revealed in glycosylphosphatidylinositol (gpi)-anchored proteins after piplc cleavage remove the great major ... | 1992 | 1500849 |
| regulation of hsp70 expression in trypanosoma cruzi by temperature and growth phase. | the steady-state level of the hsp70 mrnas of trypanosoma cruzi cultured at different temperatures and growth conditions has been analyzed by northern blotting. we show that only one size class of hsp70 mrna, of about 2.2 kb, is transcribed from the hsp70 cluster and that its transcription is constitutive at 28 degrees c. however, after a heat shock treatment at 37 degrees c for 2 h of logarithmically growing parasites, the abundance of the hsp70 mrna increased about 4-fold. a similar increase wa ... | 1992 | 1501640 |
| ultrastructure of murine cardiac ganglia in experimental chagas' disease. | albino mice, infected with trypanosoma cruzi (tulahuen strain) were sacrificed on days 7, 9, 12, 14, 16, 18, 21, 32 and 39 following infection. transmission electron microscopic examination of the cardiac ganglia revealed no ultrastructural change at day 7. at day 9 there was peri- and intraganglionic monocytic infiltration but parasites were absent. between days 12 and 16 there was intense monocytic infiltration, with intra-ganglionic presence of parasites within fibroblasts, monocytes and macr ... | 1992 | 1504456 |
| electronic properties and free radical production by nitrofuran compounds. | substitution of nifurtimox tetrahydrothiazine moiety by triazol-4-yl, benzimidazol-l-yl, pyrazol-l-yl or related aromatic nitrogen heterocycles determines changes in the quantum chemistry descriptors of the molecule, namely, (a) greater negative lumo energy; (b) lesser electron density on specific atoms, especially on the nitro group atoms, and (c) modification of individual net atomic charges at relevant atoms. these variations correlate with the greater capability of nifurtimox analogues for r ... | 1992 | 1505781 |
| a developmentally regulated cysteine proteinase gene of leishmania mexicana. | we have isolated a gene encoding a previously unreported class of trypanosomatid cysteine proteinase (cp) from the protozoan parasite leishmania mexicana. the single-copy gene (lmcpa) [corrected]. has several unusual features that distinguish it from cp genes cloned from the related species trypanosoma brucei and trypanosoma cruzi. these include a shorter c-terminal extension of only 10 amino acids and a three-amino-acid insertion, glyvalmet, close to the predicted n-terminus of the mature prote ... | 1992 | 1508041 |
| follow-up of patent and subpatent parasitemias and development of muscular lesions in mice inoculated with very small numbers of trypanosoma cruzi. | a sequential analysis of patent and subpatent parasitemias, mortality, and histopathology during acute chagas' disease experimentally produced by inoculation of 10 or 100 bloodstream forms of trypanosoma cruzi y strain in susceptible mice was carried out. parasites were searched for comparatively using three different methods: direct counting, ficoll-mi density flotation, and hemoculture. ficoll-mi density flotation promptly discriminated with high reproducibility subpatent parasitemic states no ... | 1992 | 1516671 |
| selective suppressive effects of trypanosoma cruzi infection on il-2, c-myc, and c-fos gene expression. | infection with trypanosoma cruzi is accompanied by a profound suppression of immune responses including the production of il-2. previous experiments have confirmed a correlated decrease in il-2 mrna levels in lymphoid cells from infected mice. to further define the molecular basis of this regulation, we have examined the production and degradation of mrna for il-2 and other t cell activation genes in cells from t. cruzi-infected mice. spleen cells from c57bl/6j mice infected with the brazil stra ... | 1992 | 1517573 |
| sequence of the gene for a trypanosoma cruzi protein antigenic during the chronic phase of human chagas disease. | | 1992 | 1518528 |
| succinate-dependent metabolism in trypanosoma cruzi epimastigotes. | trypanosoma cruzi epimastigotes permeabilized with digitonin (65 micrograms (mg protein)-1) to measure mitochondrial respiration were exposed to different substrates. although none of the nadh-dependent substrates stimulated respiration, succinate supported not only oxygen consumption but also oxidative phosphorylation (respiratory control ratio of 1.9 +/- 0.3) indicating that the mitochondria were coupled. the rate of nadh-dependent oxygen consumption by membrane fractions (9.4 +/- 0.7 nmol min ... | 1992 | 1518531 |
| benznidazole-induced ultrastructural alterations in rat adrenal cortex. mechanistic studies. | benznidazole (bz) (n-benzyl-2-nitro-1-imidazole acetamide) is a drug used against chagas' disease, a parasitic disease afflicting several millions of latin americans. bz administration to sprague-dawley male rats at 100 mg/kg p.o. caused subcellular alterations in the adrenal cortex involving fasciculata and reticularis zones but not in the glomerulosa. there is bz nitroreductase activity in the adrenal microsomal and mitochondrial fractions but most of it is localized in mitochondria. activity ... | 1992 | 1519244 |
| amphotericin b-induced carbohydrate changes on the trypanosoma cruzi surface membrane. | changes in the cell surface carbohydrates of trypanosoma cruzi epimastigotes induced by amphotericin b (amb) were assessed by chemical methods and by agglutination assay employing a panel of highly purified lectins of various sugar specificities. escherichia coli k12 with mannose-sensitive fimbriae was also used as an agglutination probe. amphotericin b caused a decrease in the total carbohydrate content of all glycoconjugate fractions isolated. exposure to amb strongly affected the mannose/gala ... | 1992 | 1522543 |
| anomalous electrophoretic behaviour of the major cysteine proteinase (cruzipain) from trypanosoma cruzi in relation to its apparent molecular mass. | the molecular mass of cruzipain, the major cysteine proteinase from trypanosoma cruzi epimastigotes, is 36.3 kda as calculated from its sequence; this value can increase to about 41 kda if the three potential n-glycosylation sites are glycosylated in vivo. yet the apparent molecular mass of the enzyme, as determined by sds-polyacrylamide gel electrophoresis, has been reported in a range of values from 60 to 40 kda. we show that the purified enzyme had apparent molecular masses ranging from 51 to ... | 1992 | 1526455 |
| hela cells extend and internalize pseudopodia during active invasion by trypanosoma cruzi trypomastigotes. | we show here that hela cell microfilaments can be stained by phalloidin at the sites of invasion of trypanosoma cruzi trypomastigotes, one of the infective stages of this protozoan parasite. concurrently, a projection of the hela cell plasmalemma encircles invading parasites. this plasmalemma projection is further internalized and entire membrane protrusions containing parasites are found within cytoplasmic vacuoles of the host cell. neither the microfilament staining around invading parasites n ... | 1992 | 1527184 |