Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| toxic dilatation of the colon in chagas' disease. | toxic megacolon occurs in colitis of differing aetiology. this report describes 15 patients with chagasic megacolon with this complication. the clinical signs and symptoms in all patients were pain and progressive abdominal distension accompanied by fever, severe toxaemia and shock. seven patients developed this clinical pattern after manual removal of faeces. the remaining patients had pain and abdominal distension followed by signs of severe toxaemia when first examined. nine patients underwen ... | 1992 | 1467905 |
| 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 |
| the male reproductive organs in experimental chagas' disease. ii. morphometric study of the vas deferens in the chronic phase of the disease. | a previous study showed that the vas deferens of mice in the acute phase of chagas' disease had a slight increase in the muscle layer area associated with a small decrease in the luminal area. the vas deferens of chronic chagasic mice, investigated in the present experiment, presented a marked increase in the luminal area in addition to a significant thinning of the muscle and epithelium layers. the structural alterations of the vas deferens observed in the acute and chronic phases of chagas' di ... | 1992 | 1504580 |
| 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 |
| [protection of the environment and veterinary public health activities]. | the author discusses the health status of 800 million persons who live in developing countries under conditions of absolute misery, and the 450 million on the brink of starvation, taking into account environmental factors which directly affect this situation of shortages, illness and death. data are presented on diseases directly related to environmental conditions: 200 million people infested with schistosomes and 500 million at risk of infestation. in the case of chagas' disease, 16 to 18 mill ... | 1992 | 1525417 |
| 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 |
| 1,4-dimethoxy-9(10h)-acridinone derivatives. synthesis, dna binding studies and trypanocidal activity. | new acridinonic derivatives, which are hydroxy- and methoxy-substituted in positions 1, 4, and 1,4 were prepared with a view to obtain antiparasitic drugs. these compounds were tested against trypanosoma cruzi strains and their capability of interacalation into dna was determined. nucleus substitutions, dna binding, and trypanocidal activities have been correlated. | 1992 | 1530683 |
| trypanosoma cruzi infection in immunosuppressed mice. | groups of 10 mice were challenged with 10(4) trypomastigotes of the y strain of trypanosoma cruzi. cyclophosphamide (200 mg per kg) was used for immunosuppression and administered two days before infection in one group and on day 5 after infection in a second group. enhancement of infection was more drastic in the second group, with a uniform acceleration of mortality and no clearance of the blood parasites. electron microscopy showed that the hepatocytes were colonized by t. cruzi and that the ... | 1992 | 1532162 |
| effect of antigen-specific t helper cells or interleukin-2 on suppressive ability of macrophage subsets detected in spleens of trypanosoma cruzi-infected mice as determined by limiting dilution-partition analysis. | trypanosoma cruzi, a protozoan parasite and the causative agent of chagas' disease, induces a state of lymphocyte hyporesponsiveness to both mitogenic and antigenic stimuli in mice during the acute phase of infection. addition of spleen cells from t. cruzi-infected mice (scinf) to microcultures of spleen cells from noninfected mice (scn) suppresses the responsiveness of such cultures to antigenic challenge and to mitogenic stimulation. we analyzed the regulatory cell populations in scinf by limi ... | 1992 | 1532166 |
| structural studies on the glycosylphosphatidylinositol membrane anchor of trypanosoma cruzi 1g7-antigen. the structure of the glycan core. | the 1g7-antigen is expressed by the infective metacyclic trypomastigote stage of the protozoan parasite trypanosoma cruzi. the 1g7-antigen is a 90-kda glycoprotein, present at about 40,000 copies/cell, which is anchored in the plasma membrane via a glycosylphosphatidylinositol (gpi) membrane anchor. the glycan of the gpi anchor has been isolated from immunopurified 1g7-antigen and its structure determined using a combination of methylation linkage analysis and exoglycosidase sequencing. the stru ... | 1992 | 1532392 |
| trypanosoma cruzi suppresses the expression of the p75 chain of interleukin-2 receptors on the surface of activated helper and cytotoxic human lymphocytes. | when trypanosoma cruzi is co-cultured with activated human lymphocytes the latter manifest a marked level of suppression in their capacity to express high-affinity interleukin-2 receptors (il-2r). in this study we asked whether this effect could result from reduced expression of the p75 component of the il-2r, a condition which would limit the number of heterodimeric receptors that could be assembled by activated t cells. the results of two-colour flow cytometric analyses revealed that both the ... | 1992 | 1533390 |
| evidence for the participation of the ssp-3 antigen in the invasion of nonphagocytic mammalian cells by trypanosoma cruzi. | trypomastigotes of trypanosoma cruzi have to invade mammalian cells in order to multiply. they bear on their plasma membrane a sialic acid-containing epitope (ssp-3) defined by a series of monoclonal antibodies (mabs). previous investigations have shown that fab fragments of these mabs inhibit the attachment of trypomastigotes to 3t3 fibroblasts. to further define the role of ssp-3 in invasion, here we use, as targets for infection, l cells and cho cells stably transfected with cdna coding for t ... | 1992 | 1534115 |
| detection of soluble exoantigens of trypanosoma cruzi by a dot-immunobinding assay. | a simple and highly sensitive assay for the detection of trypanosoma cruzi antigens by spotting samples on nitrocellulose membrane filters is described. the immobilized antigens are analyzed by subsequent binding of specific anti-t. cruzi immunoglobulins and secondary enzyme-labeled antibodies. trypomastigote exoantigens were determined by this technique in the supernatant from cell cultures two days after infection. the t. cruzi circulating antigens present in serum specimens collected from mic ... | 1992 | 1536381 |
| evaluation of an enzyme-linked immunosorbent assay for the diagnosis of chagas' disease using synthetic peptides. | an enzyme-linked immunosorbent assay (elisa) has been developed to detect antibodies in human sera to synthetic peptides derived from the repeating amino acid sequence in recombinant trypanosoma cruzi antigens. sixty serum samples from patients with chronic chagas' disease were used to determine the reactivity against the synthetic repeat peptides derived from clones 1, 2, 30, 36, and shed acute phase antigen (sapa). ninety-eight percent of the samples had detectable antibodies to one or more of ... | 1992 | 1536382 |
| immunodetection of antibodies in sera from symptomatic and asymptomatic chilean chagas' disease patients with trypanosoma cruzi recombinant antigens. | a panel of eight trypanosoma cruzi antigens produced by recombinant dna techniques was used to compare the reactivity of igg specificities in the sera from 45 chronic chagas' disease patients with different clinical symptoms (cardiac disease, gastrointestinal lesions, and combined syndrome) with those present in the sera from 55 asymptomatic patients in chile. all of the serum samples were first characterized for antibody to t. cruzi epimastigotes by immunofluorescence assay. all of the chagas' ... | 1992 | 1536383 |
| synergism between tumor necrosis factor-alpha and interferon-gamma on macrophage activation for the killing of intracellular trypanosoma cruzi through a nitric oxide-dependent mechanism. | intracellular replication of the protozoan parasite trypanosoma cruzi inside macrophages is essential for the production of the disease and the development of the parasite. two cd4+ t cell lines, a10 and a28, were established from t. cruzi-infected balb/c mice which specifically proliferated to parasite antigens. the trypanocidal activity of balb/c macrophages was induced upon culture with the a10, but not with the a28 t cell line. the cell-free supernatant from this a10 line, as well as from im ... | 1992 | 1537373 |
| recombinant leishmania hsp90 and hsp70 are recognized by sera from visceral leishmaniasis patients but not chagas' disease patients. | approximately 70% of the cdna clones identified by immunoscreening leishmania donovani expression libraries with serum from a patient with visceral leishmaniasis (kala-azar) were found to encode the highly conserved hsp90 and hsp70 members of the heat shock protein family. recombinant fusion proteins containing the c-terminal portions of l. donovani hsp90 and hsp70 were used as target antigens in enzyme-linked immunosorbent assays of various sera. sera from four patients with visceral leishmania ... | 1992 | 1537901 |
| clinical evaluation of an eia for the sensitive and specific detection of serum antibody to trypanosoma cruzi (chagas' disease). | a commercial eia for the detection of antibody to trypanosoma cruzi was clinically evaluated. the primary use of this test is in the diagnosis and screening of donated blood in latin america. when compared with sera positive by xenodiagnosis, the assay had a clinical sensitivity of 100%. when tested against matched hemagglutination (ha) and immunofluorescence (ifa) results (i.e., when both tests gave negative results) the eia had a specificity of 99.03% (305/308). the cross-reactivity of this te ... | 1992 | 1538165 |
| chagas' disease: decreased resistance to trypanosoma cruzi acquired infection in offspring of infected mice. | the course of trypanosoma cruzi infection was studied in an experimental model, using the offspring of mice that were chronically infected with t. cruzi. when infected two months after birth, a higher mortality rate in heavily parasitized mice occurred in these offspring than in controls born to uninfected mothers. the harmful maternal influence reached a maximum when offspring were exposed both to prenatal (placental) and postnatal (lactating) influences. it was a reversible phenomenon that led ... | 1992 | 1539744 |
| transformation of an insect symbiont and expression of a foreign gene in the chagas' disease vector rhodnius prolixus. | a shuttle plasmid was developed that is capable of replicating both in escherichia coli and in rhodococcus rhodnii, a bacterial symbiont of the chagas' disease vector rhodnius prolixus. we have been able to transform r. rhodnii with this plasmid, infect aposymbiotic r. prolixus with the transformed symbionts, select with the antibiotic thiostrepton, and re-isolate genetically altered symbionts from the insects following successive molts. symbiotic bacteria are potentially valuable as vehicles fo ... | 1992 | 1539755 |
| cd8+ cells and natural cytotoxic activity among spleen, blood, and heart lymphocytes during the acute phase of trypanosoma cruzi infection in rats. | the infection developed by wistar furth rats inoculated with the y strain of trypanosoma cruzi was the experimental model used in our study. the results showed that this infection altered considerably the cd4/cd8 lymphocyte subset ratio and the natural cytotoxic activity of mononuclear cells in the spleen, blood, and myocardial tissue. concomitantly, an expansion of the number of cells expressing major histocompatibility complex (mhc) class ii antigens was observed, as well as spontaneous develo ... | 1992 | 1541517 |
| acute chagas' disease (trypanosomiasis americana) in acquired immunodeficiency syndrome: report of two cases. | two heterosexual men, aged 31 and 40 years, with the acquired immunodeficiency syndrome and presenting with the acute form of chagas' disease are reported. the first patient, a carrier of hemophilia a, was treated for 20 years with chilean and brazilian cryoprecipitates. this patient acquired both diseases through this medium. the second patient, an inhabitant of northern chile (fourth region), was allegedly bitten by triatoma infestans and was an intravenous drug addict. the hemophilic patient ... | 1992 | 1544668 |
| do parasites reproduce by clone alone? | 1992 | 1546288 | |
| myocardial perfusion abnormalities in chronic chagas' disease as detected by thallium-201 scintigraphy. | most patients with chronic chagas' heart disease complain of chest pain. the pathophysiology of this symptom is unknown, although myocardial necrosis and fibrosis are frequent necropsy findings and cardiac autonomic impairment is a prominent feature of the disease. to evaluate the possibility of an ischemic cause for these abnormalities in 23 patients (18 men, aged 32 to 60 years, mean 42) with chronic chagas' disease complaining of chest pain, thallium-201 myocardial scintigraphy was performed ... | 1992 | 1546653 |
| transcriptional and post-transcriptional control of tubulin gene expression in trypanosoma cruzi. | we have shown that tubulin mrna accumulation is regulated at the transcriptional level during metacyclogenesis of trypanosoma cruzi, although the contribution of post-transcriptional mechanisms is also indicated. mrna heterogeneity is not restricted to beta-tubulin, and differential regulation of alpha-tubulin mrnas is observed during this stage of the parasite's life cycle. treatment of epimastigotes with the microtubule-depolymerizing agent vinblastine resulted in growth inhibition and morphol ... | 1992 | 1547017 |
| the 70-kda heat-shock protein is a major antigenic determinant in human trypanosoma cruzi/leishmania braziliensis braziliensis mixed infection. | five sera from bolivian individuals chronically infected by trypanosoma cruzi, and suffering an active leishmania braziliensis braziliensis metastatic mucocutaneous lesion were characterized. they reacted with the t. cruzi recombinant antigens that are currently used as chagas diagnostic reagents, and with several l. b. braziliensis proteins as assessed by western blot. these sera showed an intense reaction with a t. cruzi and an l. b. braziliensis polypeptide of about 70 kda. expression cloning ... | 1992 | 1548032 |
| chagas' disease. defence cuts begin to bite. | 1992 | 1549174 | |
| susceptibility of beta 2-microglobulin-deficient mice to trypanosoma cruzi infection. | the beta 2-microglobulin (beta 2m) protein associates with the products of the class i major histocompatibility (mhc) loci; this combination functions in the thymic development of and antigen presentation to cd8+ t cells. mice in which the beta 2m gene has been disrupted by homologous recombination fail to express class i mhc gene products, and therefore lack cd8+ t cells and measurable cytotoxic t-cell responses. however, beta 2m- mice appear to have normal development of both cd4+ alpha/beta t ... | 1992 | 1549177 |
| fatal meningoencephalitis caused by reactivation of trypanosoma cruzi infection in a patient with aids. | we report a case of fatal chagasic meningoencephalitis in an aids patient. acute exacerbation of chronic chagas' disease with involvement of the cns is uncommon and occurs only in immunocompromised patients. this is the third such reported reactivation and it underscores the importance of considering chagas' disease in hiv-positive patients from endemic regions. | 1992 | 1549229 |
| gap junction distribution is altered between cardiac myocytes infected with trypanosoma cruzi. | conduction disturbances frequently accompany both acute and chronic chagas' disease. to explore the possibility that changes in gap junction distribution or abundance might play a role in these disturbances, we have investigated intercellular communication between rat neonatal cardiac myocytes in cultures infected with trypanosoma cruzi. contractile activity of infected cells was characterized by regional asynchrony within the culture as well as by irregular contraction patterns. junctional cond ... | 1992 | 1551199 |
| acute chagas' disease in a recipient of a bone marrow transplant in spain: case report. | chagas' disease (american trypanosomiasis) is a very uncommon disease in non-endemic areas. a few cases in immunosuppressed patients have been reported in america. this report describes, to our knowledge, the first fatal case of acute chagas' disease in europe following bone marrow transplantation. | 1992 | 1554849 |
| biochemical evidence for the presence of arginine decarboxylase activity in trypanosoma cruzi. | trypanosoma cruzi was found to release 14co2 from radiolabeled arginine, and this effect was inhibited by either dl-alpha-difluoromethylarginine or monofluoromethylagmatine, both specific inhibitors of arginine decarboxylase (adc). furthermore, agmatine, which can be derived metabolically only by adc-mediated arginine decarboxylation, was produced when t. cruzi was incubated with radiolabeled arginine, and agmatine production was inhibited in the presence of dl-alpha-difluoromethylarginine. thes ... | 1992 | 1556653 |
| binding of antibody and resistance to lysis of trypomastigotes of trypanosoma cruzi. | epimastigote forms of trypanosoma cruzi are readily lysed by complement via the alternative pathway. neither fibroblast-derived trypomastigotes nor blood-form trypomastigotes are lysed by complement alone and few (less than 30% of the brazil strain) are lysed in the presence of parasite-specific antibody and complement. the mechanism by which trypomastigotes resist antibody-dependent, complement-mediated lysis is not clearly understood. in the present study, we have utilized flow cytometric anal ... | 1992 | 1557225 |
| chagas' disease: another cause of cerebral mass in the acquired immunodeficiency syndrome. | we report the first case of chagas' disease causing a brain mass in the acquired immunodeficiency syndrome (aids). the illness occurred in a patient living outside a traditional chagasic endemic area and represented reactivation of long dormant trypanosoma cruzi infection. a salvadoran-born resident of the united states with diagnosed aids developed hemiparesis due to a brain mass. histopathologic examination and culture of a brain biopsy specimen established that t. cruzi infection produced the ... | 1992 | 1558089 |
| cloning of repetitive dna sequences from toxoplasma gondii and their usefulness for parasite detection. | genomic dna of toxoplasma gondii was digested with the restriction endonuclease hpa ii and the resulting repetitive dna sequences were visualized after electrophoresis on agarose gels and staining with ethidium bromide. three repetitive dna sequences were isolated and cloned in the plasmid puc19. the recombinant plasmids (ptg8, ptg4 and ptg1) had inserts of 840, 440, and 180 basepairs, respectively. the estimated copy number of these cloned sequences in the t. gondii genome was approximately 800 ... | 1992 | 1558274 |
| the sequence, organization, and expression of the major cysteine protease (cruzain) from trypanosoma cruzi. | the complete sequence of the gene encoding the major cysteine protease from trypanosoma cruzi is reported. the amino acid sequence predicted from the gene sequence aligns well with members of the papain family of cysteine proteases, suggesting the name cruzain. the sequence is most closely related to the cysteine protease of trypanosoma brucei (59.3%) and the murine cathepsin l (42.2%). at least six copies of the gene are present in the genome and are organized in a tandem array of copies which ... | 1992 | 1559982 |
| sequence analysis of small subunit ribosomal rna genes and its use for detection and identification of leishmania parasites. | the sequence of the most variable part of the small subunit ribosomal rna (ssu rrna) gene, comprising 800 bases, was analysed for 9 leishmania taxa and compared with those of trypanosoma brucei, trypanosoma cruzi and crithidia fasciculata. considerable differences were observed between the sequence of the leishmania taxa on the one hand and those of crithidia and trypanosoma on the other. amongst the leishmania taxa only a few point mutations were found, all located within 2 sequence blocks in t ... | 1992 | 1565128 |
| specific functional domains of mitochondrial hsp70s suggested by sequence comparison of the trypanosome and yeast proteins. | 1992 | 1565130 | |
| electrocardiographic alterations during treatment of mucocutaneous leishmaniasis with meglumine antimoniate and allopurinol. | the electrocardiographic (ecg) changes in bolivian patients with mucocutaneous leishmaniasis, treated with meglumine antimoniate and allopurinol, were evaluated. electric changes due to the antimonial compound appeared in 45% of the patients, and consisted of repolarization alteration, principally affecting the t wave and the s-t segment. the changes disappeared within 2 months following the end of the antimonial treatment. in patients with associated chagas disease and leishmaniasis, antimonial ... | 2013 | 1566297 |
| sylvatic american trypanosomiasis in argentina. trypanosoma cruzi infection in mammals from the chaco forest in santiago del estero. | trypanosoma cruzi infection in sylvatic mammals of the quebracho woods of the eastern part of santiago del estero province, argentina, was studied from october 1984 to december 1987. 301 mammals of 20 different species were caught. t. cruzi, characterized biologically and biochemically, was isolated by xenodiagnosis from 23 of 72 (32%) didelphis albiventris opposums, 2/36 (5.5%) conepatus chinga skunks, and one ferret (galictis cuja). 53 opossum refuges were located and triatomine bugs were foun ... | 1992 | 1566301 |
| analysis of anti-keyhole limpet haemocyanin antibody in brazilians supports its use for the diagnosis of acute schistosomiasis mansoni. | antibody (immunoglobulin (ig) g) to the haemocyanin of the keyhole limpet (klh) (megathura crenulata), which shares a well defined carbohydrate epitope with the surface of schistosomula of schistosoma mansoni, was determined by enzyme-linked immunosorbent assay (elisa) in the sera of brazilians with acute schistosomiasis. of 53 such individuals tested, 51 had a level of klh reactivity in excess of the mean +2 standard deviations of that exhibited by chronically infected individuals. this differe ... | 1992 | 1566306 |
| plasmodium chabaudi and trypanosoma cruzi infections can reverse igg2ab chronic suppression in mice. | the effects of infections with plasmodium chabaudi or trypanosoma cruzi on chronic cd8+ t cell dependent igg2ab suppression were analyzed in homozygous ighb/b adult mice. these parasites are known to induce a cd4+ t cell dependent polyclonal activation characterized in particular by a considerable increase in igg2a expression. we report here that infection with either parasite reversed the igg2ab suppression in 18 out of 32 mice. however, in mice treated with anti-cd4 mab in parallel to the para ... | 1992 | 1567793 |
| induction of macrophage activation and opsonizing antibodies by trypanosoma cruzi subpopulations. | macrophage activation and production of opsonizing antibodies were studied in mice either infected with a lethal and reticulotropic trypanosoma cruzi strain, ra, or with a non lethal and myotropic strain, ca-i, as well as with a clone, k98 (derived from ca-i), similar to the parental strain. measurement of macrophage respiratory burst by chemiluminescence disclosed that t. cruzi infection induced an enhancement of the respiratory burst, no matter the parasite subpopulation employed. but, while i ... | 1992 | 1570171 |
| structural characterization of neutral glycosphingolipids from trypanosoma cruzi. | the major neutral glycosphingolipids from trypanosoma cruzi ceramide mono- and dihexosides (cmh and cdh, respectively) were analysed after chromatographic purification using 1h 500 mhz nuclear magnetic resonance spectroscopy and fast atom bombardment mass spectrometry. the ceramide monohexoside fraction (cmh) contained both glucosyl- and galactosylceramides. after peracetylation, the cmh fraction was separated into 2 subfractions, cmh-coh and cmh-cn, containing either hydroxy fatty acids or n-fa ... | 1992 | 1574084 |
| characterization of a highly repeated interspersed dna sequence of trypanosoma cruzi: its potential use in diagnosis and strain classification. | in the present paper we report the characterization of a repetitive dna sequence from the genome of the maracay strain of trypanosoma cruzi. the sequence is 1025 nucleotides long and represent about 7% of the total nuclear dna of the parasite with a copy number of 1-2 x 10(4) copies per genome. it is also present in a high copy number in several strains of t. cruzi but absent from other trypanosomatids and from the human genome. the dna sequence is interspersed and present on many chromosomes. w ... | 1992 | 1574085 |
| anti-trypanosoma-cruzi-proteinase antibodies and immunoprotection in experimental chagas' disease. | to verify whether anti-trypanosoma-cruzi-proteinase antibodies are able to play a role in the development of chagas' disease, cba/j and c57bl/6 mice were immunized with purified proteinase fractions: antibody production was studied and passive immunization experiments were carried out. no significant differences were observed in the titre, isotype composition and specificity of the antibodies produced by the mouse strains. immune sera produced in one strain was able to protect mice of both strai ... | 1992 | 1574641 |
| use of recombinant antigens for the accurate immunodiagnosis of chagas' disease. | we tested two trypanosoma cruzi recombinant antigens in a diagnostic test for chagas' disease. these antigens were a cytoplasmic repetitive antigen (cra) and a flagellar repetitive antigen (fra). the results indicate that the recombinant antigens give better results when used in combination than when used separately, and that the removal of the beta-galactosidase portion of the recombinant fusion proteins increases the specificity of the diagnostic test for chagas' disease. in addition, a direct ... | 1992 | 1575289 |
| production of monoclonal antibodies for the identification of a strain of trypanosoma cruzi. | mouse monoclonal antibodies (mab) were produced against antigen from epimastigote forms of the montalvania 17 strain of trypanosoma cruzi. several t. cruzi-specific mab were obtained, some of which were capable of discriminating between different t. cruzi strains. | 1992 | 1575290 |
| control of the transmission of chagas' disease in mambai, goias, brazil (1980-1988). | the results of entomologic surveillance conducted after chagas' disease control in mambai, goias, brazil are reported for the years 1985-1988, including a summary of results from 1980 to 1988. a progressive decrease in the incidence of triatoma infestans in houses reached zero in 1988. the threat of secondary vector colonization and the continued need for vigilance are discussed. | 1992 | 1575291 |
| result of a first step toward community-based surveillance of transmission of chagas' disease with appropriate technology in rural areas. | the objective of this work was to develop an effective methodology for the surveillance of chagas' disease vectors in rural areas. it was based on the use of sensor boxes and portable mini-pumps to be integrated into the regular health promotion activities of the primary health care (phc) agents. the proposed methodology involves a continuous passive intradomiciliary detection of triatomines by sensor boxes that are monitored quarterly by phc agents. insecticidal treatment of the houses was perf ... | 1992 | 1575292 |
| isolation and partial characterization of a high-molecular-weight dna polymerase from leishmania mexicana. | this paper describes for the first time the isolation and characterization of a high-molecular-weight predominant dna polymerase from the genus leishmania, which are parasitic flagellated protozoa. like mammalian dna polymerase alpha, the leishmanial dna polymerase, designated dna polymerase a, is of high-molecular-weight, is sensitive to n-ethylmaleimide and is inhibited by high ionic strength. unlike mammalian dna polymerase alpha, but similar to the predominant dna polymerase isolated from th ... | 1992 | 1576158 |
| electrocardiographic and echocardiographic features of trypanosomiasis in dogs inoculated with north american trypanosoma cruzi isolates. | purebred beagles were inoculated with trypanosoma cruzi isolates from a north american opossum or armadillo (tc-w), and dog (tc-d). although tc-d established infection in dogs, the dogs did not develop cardiac abnormalities. dogs inoculated with tc-w developed acute myocarditis associated with increases in p-r interval, atrioventricular block, depression of r wave amplitude and shifts in mean electrical axis. echocardiograms were normal during this stage. three tc-w-inoculated dogs died during t ... | 1992 | 1586022 |
| the male reproductive organs in the chronic phase of experimental chagas' disease. | a previous study showed amastigote forms of trypanosoma cruzi in the sex organs of male mice 15 days after inoculation. the purpose of the present work was to investigate the sequelae occurring in the male reproductive system during a later phase of chagas' disease. depleted germinal epithelium and release of immature germ cells into the tubular lumen were observed in the testis of chronic chagasic mice. the relative weights of the epididymis, vas deferens and seminal vesicle were significantly ... | 1992 | 1590593 |
| effects of 2(3)-tert-butyl-4-hydroxyanisole (bha) on in situ mitochondria of trypanosoma cruzi. | results obtained with in situ mitochondria of trypanosoma cruzi showed that this protozoon had only two energy coupling sites, sites ii and iii that correspond to higher eukaryote mitochondria. rotenone did not inhibit the oxygen uptake of the parasite. these results suggest that the nadh-ubiquinone segment of the respiratory chain has no activity. studies with in situ mitochondria confirmed that bha, an antioxidant food additive, blocks the mitochondrial electron transport chain at the succinat ... | 1992 | 1592119 |
| depressed adjuvant arthritis in chronically trypanosoma cruzi infected rats: reversal by cyclophosphamide. | chronically trypanosoma cruzi infected "i" rats and syngeneic naive recipients, transferred with a t cell enriched spleen cell population from infected donors, develop an attenuated arthritis when challenged with complete freund's adjuvant. we report that cyclophosphamide, 40 mg/kg body weight, given 48 h before induction, was able to reestablish or exacerbate adjuvant arthritis in infected and control rats, respectively. although the t cell enriched spleen cells from infected donors continued t ... | 1992 | 1593569 |
| detection of peptidases in trypanosoma cruzi epimastigotes using chromogenic and fluorogenic substrates. | detergent extracts of trypanosoma cruzi epimastigotes catalysed the hydrolysis of a range of amino-acyl and peptidyl p-nitro-anilides and aminomethylcoumarins. at least three enzymes were detected that cleave z-phe-arg-mca. two of these were optimally active at alkaline ph, the other at ph 4.0. of the two enzymes with alkaline ph optima, one was a cysteine peptidase and was unable to cleave bz-arg-mca readily, whilst the other cleaved bz-arg-mca and was inhibited by diisopropyl fluorophosphate. ... | 1992 | 1594295 |
| chagas' disease in the united states. | 1992 | 1595564 | |
| does chagas' disease exist as an undiagnosed form of cardiomyopathy in the united states? | 1992 | 1595572 | |
| the mechanism by which microorganisms avoid complement attack. | the complement system provides a critical level of defense against bacterial invasion. various microorganisms have evolved a variety of mechanisms to allow them to avoid complement lytic and opsonic activity. these range from the formation of factors that destroy activity of complement proteins to the evolution of surface structures that fail to bind, facilitate degradation of, or shed, complement proteins. the range of factors associated with bacterial complement resistance is reviewed here. | 1992 | 1596364 |
| dl-alpha-difluoromethylarginine inhibits intracellular trypanosoma cruzi multiplication by affecting cell division but not trypomastigote-amastigote transformation. | dl-alpha-difluoromethylarginine (dfma), a specific, irreversible inhibitor of arginine decarboxylase (adc), decreases the capacity of trypanosoma cruzi to invade and multiply within different types of mammalian host cells in vitro. in this work we found that inhibition of intracellular growth results from selective impairment of amastigote division without appreciable alteration of the capacity of the invading trypomastigotes to transform into the replicative amastigote form. addition of agmatin ... | 1992 | 1597782 |
| changes in fibroblast-derived trypomastigotes of trypanosoma cruzi during long-term culture. | fibroblast-derived trypomastigotes (fdts) of trypanosoma cruzi that had been in culture for extended periods of time were found to differ in their ability to proliferate in culture when compared to blood-form trypomastigotes (bfts) and fdts that had been recently established from blood-forms. "old" fdts transform into amastigotes/spheromastigotes and epimastigotes and readily incorporate [3h]thymidine in medium alone or in the presence of mouse spleen cells, whereas "new" fdts and bfts did not i ... | 1992 | 1597800 |
| trypanosoma cruzi in wild raccoons and opossums in north carolina. | trypanosoma cruzi was isolated from 1 of 12 (8.3%) opossums and 3 of 20 (15%) raccoons from the piedmont area of north carolina. although t. cruzi has been isolated previously from wild mammals in the southern united states, the present study is the first published report of naturally occurring t. cruzi infection of wild mammals in north carolina. all 4 isolates were maintained successfully in axenic culture and in murine fibroblasts. in addition, intraperitoneal injection of 1 x 10(6) culture f ... | 1992 | 1597808 |
| nucleotide sequence of a cdna encoding a trypanosoma cruzi acidic ribosomal p1 type protein. | 1992 | 1598221 | |
| an improved polymerase chain reaction assay to detect trypanosoma cruzi in blood. | amplification by the polymerase chain reaction of trypanosoma cruzi satellite dna was used to enhance sensitivity in the detection of the parasite in blood, with the ultimate goal of improving diagnosis of the chronic phase of chagas' disease. two contiguous oligonucleotides were synthesized corresponding to the most conserved region of the 195-basepair repeated sequence and used as primers for the amplification reaction. nineteen femtograms of parasite dna that was amplified in the presence of ... | 1992 | 1599057 |
| isozyme variability and differentiation between rhodnius prolixus, r.robustus and r.pictipes, vectors of chagas disease in venezuela. | enzyme polymorphism in triatomine bugs of the genus rhodnius (hemiptera: reduviidae), vectors of chagas disease, is analysed using both starch and polyacrylamide gel electrophoresis. out of forty-five enzymes assayed, the electromorphs of seventeen of them: ao, ca, dia, es, es-a, fh, gpd, g6pd, gpi, mdh, me, 6pgd, pgm, acon, acph, lap and sod, involving twenty-two putative structural loci, were scorable. these gene-enzyme systems were therefore selected for routine characterization of r.prolixus ... | 1992 | 1600225 |
| determinants of the domiciliary density of triatoma infestans, vector of chagas disease. | in two heavily infested rural villages of santiago del estero, argentina, where no indoor-spraying with residual insecticides had ever been carried out by official control services, we studied the influence of roof and wall structure, domestic use of insecticide, family size and the number of domestic dogs, on the domiciliary density of triatoma infestans (klug). bug density was significantly associated with (1) the interaction between insecticide use and type of roof, (2) the structure of indoo ... | 1992 | 1600232 |
| clinical and epidemiologic studies of chagas' disease in rural communities of oaxaca, mexico, and an eight-year followup: ii. chila. | a seroepidemiologic survey conducted in 1971 in the rural pacific coastal community of chila in the mexican state of oaxaca showed an unusually high prevalence of antibody against the chagas' disease agent trypanosoma cruzi. further studies were undertaken in 1973 and 1981 to (1) determine the pathologic impact of t. cruzi infection in humans, (2) investigate the natural history of the disease, (3) confirm that serologically positive persons were parasitologically positive, and (4) evaluate whet ... | 1992 | 1600437 |
| cloning, sequencing and distribution of the salmonella typhimurium lt2 sialidase gene, nanh, provides evidence for interspecies gene transfer. | the salmonella typhimurium lt2 sialidase (neuraminidase, ec 3.2.1.18) structural gene, nanh, has been cloned and sialidase overproduced from multicopy plasmids in escherichia coli. sialidase expression was regulated positively by camp. in contrast, certain tn1000 insertions located upstream of nanh coding sequences reduced sialidase activity. a nanh chromosomal insertion mutation constructed by marker exchange demonstrated a single sialidase gene copy in s. typhimurium lt2. the complete nucleoti ... | 1992 | 1602967 |
| [determination of soluble interleukin-2 receptor in patients with american trypanosomiasis in panama]. | the quantitative determination of inter leukin-2 receptor (sil-2r) in the serum of patients with acute or chronic chagas disease is compared with values found in normal individuals. the mean value of soluble il-2r in patients with acute chagas' disease was found to be 3,282 +/- 171 u/ml. the mean value of sil-2r in serum samples from chronic chagasic patients was 511 +/- 207 u/ml, while in the control or "normal" group of persons the mean value for sil-2r was 366 +/- 108 u/ml. in patients with e ... | 1992 | 1603982 |
| histamine levels in tissues of trypanosoma cruzi-infected mice. | histamine levels of several organs from mice chronically infected with a myotropic strain of trypanosoma cruzi were determined by bioassay. an increase in histamine content was observed in stomach, small intestine, colon, heart and skeletal muscle, when compared with noninfected weight and age-matched mice. these results suggest that mast cells, the main storage site of peripheral histamine, can play a role in the inflammatory and/or immunologic components of experimental trypanosomiasis. | 1992 | 1609655 |
| clinical characteristics of acute myocardial infarction in patients with chagas' disease. | from 1981 to 1988, 404 patients at our institution were found to have acute myocardial infarction. of them, 18 (4%) had a positive fixation test for chagas' disease. patient age ranged from 41 to 80 years (median = 59). eleven patients were males. eighteen nonchagasic patients were matched by 2 year age intervals and sex with each chagasic patient. before acute myocardial infarction, there were no differences between chagasic and nonchagasic patients with regard to the proportion of stable angin ... | 1992 | 1612801 |
| cytokine activation of human macrophages infected with hiv-1 to inhibit intracellular protozoa. | peripheral blood mononuclear cells (pbmcs) from hiv-seronegative donors were infected in vitro with hiv-1. infection was monitored by cytopathology, supernatant p24 antigen, and by immunocytochemical staining. after 14 days in culture, approximately 70-90% of the cells became infected with hiv, as indicated by cell fusion and immunostaining for virus. at this time, recombinant huifn-gamma was added to the cultures, followed by infection 24 h later with the intracellular protozoan parasites toxop ... | 1992 | 1613664 |