Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| [cerebral embolism of cardiac origin]. | we reviewed 538 charts of patients hospitalized with acute ischemic strokes between 1983 and 1991. the inclusion criteria for cardioembolism were: 1) sudden onset and maximal neurological focal deficit from the beginning, 2) brain ct showing an ischemic infarct, hemorrhagic infarct, or multiple infarcts, 3) cardioembolic sources demonstrated by echocardiography or heart catheterization, and 4) absence of stenotic-occlusive cerebrovascular disease. sixty-nine patients (12.8%) filled the criteria ... | 1992 | 1342685 |
| immunoregulatory mechanisms and chagas' disease. | during the course of experimental chagas' disease, several immune disorders occur. in the acute phase, t and b cell polyclonal activation is associated to immunosuppression. at the chronic stage, t cells--of the th2 subset--participate to the pathology characteristic of chagas' disease. data obtained after infection of balb/xid mice suggest that polyclonal activation may be dependent on b1 (cd5) cell-activation. moreover, these mice fail to develop the pathological features of the chronic infect ... | 1992 | 1342703 |
| trypanosoma cruzi recognition by macrophages and muscle cells: perspectives after a 15-year study. | macrophages and muscle cells are the main targets for invasion of trypanosoma cruzi. ultrastructural studies of this phenomenon in vitro showed that invasion occurs by endocytosis, with attachment and internalization being mediated by different components capable of recognizing epi- or trypomastigotes (try). a parasitophorus vacuole was formed in both cell types, thereafter fusing with lysosomes. then, the mechanism of t. cruzi invasion of host cells (hc) is essentially similar (during a primary ... | 1992 | 1342716 |
| effects of azadirachtin on rhodnius prolixus: immunity and trypanosoma interaction. | the effects of azadirachtin, a tetranortriterpenoid from the neem tree azadirachta indica j., on both immunity and trypanosoma cruzi interaction within rhodnius prolixus and other triatomines, were presented. given through a blood meal, azadirachtin affected the immune reactivity as shown by a significant reduction in numbers of hemocytes and consequently nodule formation following challenge with enterobacter cloacae beta 12, reduction in ability to produce antibacterial activities in the hemoly ... | 1992 | 1342719 |
| [dynamics of chagas infection transmission in chile: model and simulation]. | triatoma infestans is the principal vector for chagas disease in chile. although there is enough epidemiological information about human infection, the effect of vector and host (animals and man) populations interrelations over chagas disease prevalence has not been studied. this work studies a determinist mathematical model for the dynamics of chagas disease transmission by triatoma infestans, relating entomological population parameters with infection propagation. the effect of invasion of sus ... | 1992 | 1343375 |
| [esophageal achalasia of chagasic origin: report of a case diagnosed in the pre-symptomatic stage]. | a 42 year old male that presented with functional gastrointestinal symptoms is presented. x ray examination showed an esophageal diameter of 3 cm, measured 6 cm above the gastroesophageal junction. this finding, according to previous experiences of the authors, is highly suggestive of chagasic esophageal involvement. the patient resided in a highly endemic area for chagas disease; hemagglutination, latex agglutination and elisa serological tests for chagas disease were positive. the manometric s ... | 1992 | 1343381 |
| risk factors for trypanosoma cruzi infection among blood donors in central brazil. | characteristics and possible risk factors associated with trypanosoma cruzi infection among blood donors were assessed within a routine screening programme in blood banks in an endemic area of chagas disease. 6,172 voluntary blood donors were interviewed and tested for anti-t. cruzi antibodies by haemagglutination and complement fixation tests in six blood banks in goiânia-central brazil from october 1988 to april 1989. an overall prevalence of 2.3% for t. cruzi infection was obtained, being 3.3 ... | 1992 | 1343642 |
| evaluation of some organic compounds on bloodstream forms of trypanosoma cruzi. | accidental transmission of chagas' disease to man by blood transfusion is a serious problem in latin-america. this paper describes the testing of several synthetic, semi-synthetic, and natural compounds for their activity against blood trypomastigotes in vitro at 4 degrees c. the compounds embody several types of chemical structures: benzoquinone, naphthoquinone, anthracenequinone, phenanthrenequinone, imidazole, piperazine, quinoline, xanthene, and simple benzenic and naphthalenic derivatives. ... | 1992 | 1343643 |
| cytogenetics as a tool for triatomine species distinction (hemiptera-reduviidae). | several cytogenetic traits were tested as species diagnostic characters on five triatomine species: rhodnius pictipes, r. nasutus, r. robustus, triatoma matogrossensis and t. pseudomaculata. four of them are described for the first time. the detailed analysis of the meiotic process and the application of c-banding allowed us to identify seven cytogenetic characters which result useful to characterize and differentiate triatomine species. | 1992 | 1343644 |
| macrophage activation and histopathological findings in calomys callosus and swiss mice infected with several strains of trypanosoma cruzi. | peritoneal macrophage activation as measured by h2o2 release and histopathology was compared between swiss mice and calomys callosus, a wild rodent, reservoir of trypanosoma cruzi, during the course of infection with four strains of this parasite. in mice f and y strain infections result in high parasitemia and mortality while with silvatic strains costalimai and m226 parasitemia is sub-patent, with very low mortality. h2o2 release peaked at 33.6 and 59 nm/2 x 10(6) cells for strains y and f, re ... | 1992 | 1343663 |
| quantification of trypanosoma cruzi in the heart, lymph nodes and liver of experimentally infected mice, using limiting dilution analysis. | limiting dilution analysis was used to quantify trypanosoma cruzi in the lymph nodes, liver and heart of swiss and c57bl/10 mice. the results showed that, in swiss and bl/10 mice infected with t. cruzi y strain, the number of parasites/mg of tissue increased during the course of the infection in both types of mice, although a greater number of parasites were observed in heart tissue from swiss mice than from bl/10. with regard to liver tissue, it was observed that the parasite load in the initia ... | 1992 | 1343664 |
| trypanosomatidae codon usage and gc distribution. | a study of trypanosomatidae gc distribution and codon usage is presented. the codon usage patterns in coincidence with the phylogenetical data are similar in crithidia and leishmania, whereas they are more divergent in trypanosoma brucei and t. cruzi. the analysis of the gc mutational pressure in these organisms reveals that t. brucei, and to a lesser extent t. cruzi, have evolved towards a more balanced use of all bases, whereas leishmania and crithidia retain features of a primeval genetic app ... | 1992 | 1343666 |
| trypanosoma cruzi: infectivity and virulence of trypomastigotes incubated with leukocytes and serum from patients with chagas' disease. | an important issue for the understanding of the host-parasite relationship in chagas' disease is the extent of the action of the immune system on the parasite. to advance our understanding of this aspect, we evaluated the effect of leukocytes and/or sera from patients with chagas' disease on trypomastigotes of trypanosoma cruzi. we incubated, in vitro, leukocytes and sera, from patients with chagas' disease without evidence of heart disease (inf), patients with chagasic cardiopathy (cdm) and hea ... | 1992 | 1343741 |
| molecular mimicry between trypanosoma cruzi and host nervous tissues. | increasing evidence suggests that in chagas' disease chronic-phase pathology is autoimmune in nature. there are at least two nonexclusive explanations for the generation of autoimmunity in chagas disease: a) infection with the parasite perturbs immunoregulation, leading to loss of tolerance for self-antigens; b) immune recognition of t. cruzi antigens is crossreactive with selected mammalian antigens, leading to autoimmunity (molecular mimicry). through this latter mechanism, t. cruzi antigens t ... | 1992 | 1343745 |
| the colonization of cartilage and ligaments by trypanosoma cruzi. | 1992 | 1343787 | |
| schizotrypanids: the occurrence of dermatitis in immunodeficient animals infected with trypanosoma cruzi. | congenitally athymic nude balb/c (nu/nu) and their phenotypically normal adult and neonate littermates (nu/+), the c3h/hen as well, were intraperitoneally infected with two strains (y or cl) or trypanosoma cruzi. the nude mice and the neonates developed a severe parasitaemia, the susceptible c3h/hen also presented high level and adult balb/c mice presented parasitaemia similar to that observed in outbred mice. erythematous skin lesions were observed initially in infected athymic nude and neonate ... | 1992 | 1343802 |
| interrelationship between schistosomiasis and concomitant diseases. | the biological literature contains many examples of mutual influences between different species of parasites, especially with respect to concomitant helminth infections. several situations are known in which the association of infection by schistosoma mansoni with other pathogens in the same host results in a type of disease which differs from the simple summation of the individual effects of each infection. the present study concerns concomitant infections involving s. mansoni and enterobacteri ... | 1992 | 1343911 |
| proceedings of the xix annual meeting on basic research in chagas' disease and the viii meeting of the brazilian society of protozoology. caxambu, november 10-13, 1993. abstracts. | 1980 | 1344807 | |
| [the oral route: an access port for trypanosoma cruzi]. | rats and mice were inoculated by oral route with t. cruzi from: 1. infected mice blood, 2. experimentally infected triatomines feces, 3. experimentally infected alive triatomines, and 4. free cell cultures. mice showed to be more susceptible to the infection than rats. mice exhibited to be infected: 30% with blood forms, 85% with triatomines feces, 75% with alive triatomines and 35% with culture forms. rats exhibited to be infected: 10%, with blood forms, 45% with triatomines feces, 60% with ali ... | 1992 | 1345302 |
| [interaction of a mixture of epimastigotes and tripomastigotes from a culture of a mexican isolate of trypanosoma cruzi with mouse macrophages]. | chagas disease, a cause of important morbo-lethality in latinamerica, is produced by a protozoan which has a circulating and tissular phase the trypanosoma cruzi. adhesion between t. cruzi and phagocytes is the first step in cellular parasitism, which has a central role in pathogenesis. although there are studies on parasite phagocyte interaction with some strains of t. cruzi, and it is known that biological variation does exist. we now report the first studies with a mexican isolate using a mix ... | 1992 | 1345303 |
| chagas' disease in peruvian inca mummy. | 1992 | 1345858 | |
| evaluation of recombinant trypomastigote surface antigens of trypanosoma cruzi in screening sera from a population in rural northeastern brazil endemic for chagas' disease. | a perfect serologic test for infection with trypanosoma cruzi does not exist. this study uses recombinant t. cruzi surface proteins in the antibody capture enzyme linked immunoabsorption assay (elisa); and compares this approach to the more standard immunofluorescence assay (ifa). three recombinant antigens are studied: f1-160 corresponding to the 160 kda flagellar associated surface protein of trypomastigotes (the motile form of t. cruzi in mammalian infections); and sa 85-1.1 and 1.2 correspon ... | 1992 | 1348602 |
| two dna polymerases from trypanosoma cruzi: biochemical characterization and effects of inhibitors. | 1. two dna polymerases have been partially purified from trypanosoma cruzi epimastigotes by deae-cellulose, phosphocellulose, and dna agarose chromatography. 2. both enzyme activities were characterized by several biochemical criteria. 3. they showed different sensitivity to kcl and displayed characteristic mg2+ and mn2+ requirements, although they exhibited almost identical primer-template utilization. 4. the preferred substrates were poly dc-oligo dg, activated calf thymus dna, and poly dt-oli ... | 1992 | 1350966 |
| presence and subcellular localization of tyrosine aminotransferase and p-hydroxyphenyllactate dehydrogenase in epimastigotes of trypanosoma cruzi. | cell-free extracts of epimastigotes of trypanosoma cruzi contain tyrosine aminotransferase (tat) and p-hydroxyphenyllactate dehydrogenase (phpldh). the tat activity could be separated from aspartate aminotransferase (asat) by polyacrylamide gel electrophoresis or deae-cellulose chromatography; the latter procedure also allowed complete separation of phpldh. the subcellular localization of both t. cruzi enzymes, as determined by digitonin extraction, subcellular fractionation by differential cent ... | 1992 | 1351016 |
| control of trypanosoma cruzi infection in mice deprived of t-cell help. | the role of cd4+ t lymphocytes in the resistance of balb/c mice to trypanosoma cruzi was examined by in vivo depletion using monoclonal anti-cd4 antibodies (moabs). when the administration of moabs was initiated 2 days before, or 5 to 12 days after the infection (dpi) with 50 bloodstream-form trypomastigotes of the tulahuén strain, mice showed an enhanced susceptibility to the parasite. specific igg, but not igm responses, were inhibited in anti-cd4-treated and infected mice. however, when anti- ... | 1992 | 1354391 |
| molecular characterization of mexican stocks of trypanosoma cruzi using total dna. | seventeen mexican trypanosoma cruzi stocks and five south american reference strains were analyzed by hind iii restriction fragment length polymorphisms associated with ribosomal rna gene spacers and by hinfi digestion patterns of total dna. our findings demonstrate the occurrence of genetic heterogeneity within these stocks. hierarchic and non-hierarchic clustering of these molecular characters allowed the formation of groups that correlate with the geographic origin of the stocks. the hinfi di ... | 1992 | 1354415 |
| rationally designed selective inhibitors of trypanothione reductase. phenothiazines and related tricyclics as lead structures. | trypanothione reductase, an essential component of the anti-oxidant defences of parasitic trypanosomes and leishmania, differs markedly from the equivalent host enzyme, glutathione reductase, in the binding site for the disulphide substrate. molecular modelling of this region suggested that certain tricyclic compounds might bind selectively to trypanothione reductase without inhibiting host glutathione reductase. this was confirmed by testing 30 phenothiazine and tricyclic antidepressants, of wh ... | 1992 | 1355650 |
| [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 |
| parasympathetic denervation of the iris in chagas' disease. | the parasympathetic innervation of the iris along with cardiovascular reflexes involving parasympathetic and sympathetic function were studied in 45 patients with chagas's disease and in 36 controls. the autonomic features in chagas' disease included 15 with cardiomyopathy, three with megaoesophagus and five with megacolon. none of the patients had orthostatic hypotension. parasympathetic cardiac reflexes (deep breathing 30:15 ratio, valsalva) were abnormal. there were exaggerated pupillary resp ... | 1992 | 1392546 |
| 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 | |
| renal transplantation in patients with chagas' disease: a long-term follow-up. | 1992 | 1412896 | |
| renal transplantation and chagas' disease. | 1992 | 1412905 | |
| 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 |
| effects of phenytoin on the ventricular tachyarrhythmias of chronic chagas' disease. | the effects of phenytoin on the ventricular tachyarrhythmias of 11 patients with chronic chagasic myocarditis were investigated, and correlated with the serum phenytoin levels. physical examination, laboratory tests and 24- to 48-h ambulatory electrocardiographic recordings were performed before, during (7-14 days) and after treatment with phenytoin (4-6 mg/kg/day, orally, in three divided doses). significant (greater than 90%) reduction of couplets, bigeminy and runs of ventricular tachycardia ... | 1992 | 1428256 |
| 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 |