Biomedical subjects

M Rojas

Publications and source records attributed to M Rojas.

At least 55 records · Page 3Linked to original sources

PubMed1999

Genetic cancer susceptibility and DNA adducts: studies in smokers, tobacco chewers, and coke oven workers.

Preventive strategies require identification of cancer-susceptible individuals resulting from combinations of carcinogen exposure, cancer-predisposing genes, and lack of protective factors. To this aim, related to tobacco smoking and chewing (betel quid), we measured PAH-DNA adducts as exposure and susceptibility markers together with genetic polymorphism in drug-metabolizing enzymes related to CYP1A1, GSTM1, and GSTT1 genes in case-control studies. (+)-anti-Benzo(a)pyrene diol-epoxide (BPDE)-DNA adduct levels were quantitated in white blood cells (WBCs) and lung tissue DNA. CYP1A1 polymorphism and GSTM1 or GSTT1 gene deletion was analyzed in genomic DNA from lung parenchyma, WBCs, or oral biopsies (leukoplakia patients from India) and from oral exfoliated cells (healthy controls). Results from lung cancer patients and PAH-exposed coke oven workers correlated CYP1A1-GSTM1 genotype combinations with BPDE-DNA adduct levels. Smokers with homozygous CYP1A1 variant and GSTM1 null had the highest adduct levels and were, as shown in Japanese smokers, most susceptible to lung cancer. In oral premalignant leukoplakia cases associated with betel quid/tobacco chewing, the prevalence of the GSTM1 null and GSTT1 null genotypes was significantly higher, as compared to healthy controls. The combined GST null genotypes prevailed in 60% of the cases with none detected in controls. Based on this short review we conclude that (i) BPDE-DNA adduct levels resulting from "at risk" genotype combinations may serve as markers to identify most susceptible individuals; (ii) in Indian betel quid/tobacco chewers, the null genotypes of GSTM1 and GSTT1 greatly increased the risk for developing oral leukoplakia.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗

PubMed1999

Genomic compatibility between two phyllotine rodent species evaluated through their hybrids.

In order to investigate the genomic compatibility between allopatric rodent species, Phyllotis darwini and Phyllotis magister, we have studied several cytogenetic and reproductive features of their laboratory hybrids. Of thirty-one pairings between species, only five were successful, producing eleven newborns. Like parents, hybrids had 38 metacentric chromosomes, except for the subtelocentric Y chromosome inherited from P. magister. There was almost total C and G band correspondence between homeologous autosomes. However, parental sex chromosomes had different morphology, C and G bands. Ag-NOR bands appeared as small telomeric Ag+ regions, distributed in four chromosomal pairs of darwini, three of magister and four homeologous chromosomes of the hybrids. The three forms had similar indexes of NOR activity per cell, in spite of the variability in NOR expression which was always detected. Usually, only one member of parental homologous chromosomes showed AgNOR+; nevertheless, both homeologous chromosomes were active in many hybrid cells. The frequencies of cells that expressed their ribosomal genes in the two homologous or homeologous NOR chromosomes were similar in parental and hybrid cells. These results strongly suggest that ribosomal genes of both parental genomes would function codominantly in the hybrids. The gonad histological and morphometric analyses showed that hybrids conformed to Haldane's rule, since females were fertile and males were infertile. Our results indicate that P. darwini and P. magister genomes can function in relative harmony and compatibility when they are placed together in their laboratory generated hybrids, suggesting that these species have few genetic differences, probably because they have recently diverged.

Animals↗

PubMed1999

Detection of the 70-kilodalton histoplasma capsulatum antigen in serum of histoplasmosis patients: correlation between antigenemia and therapy during follow-up.

Histoplasmosis is an important systemic fungal infection, particularly among immunocompromised individuals, who may develop a progressive disseminated form which is often fatal if it is untreated. In such patients, the detection of antibody responses for both diagnosis and follow-up may be of limited use, whereas the detection of Histoplasma capsulatum var. capsulatum antigens may provide a more practical approach. We have recently described an inhibition enzyme-linked immunosorbent assay (ELISA) for the detection in patients' sera of a 69- to 70-kDa H. capsulatum var. capsulatum-specific antigen which appears to be useful in diagnosis. To investigate its potential for the follow-up of histoplasmosis patients during treatment, antigen titers in the sera of 16 patients presenting with different clinical forms of histoplasmosis were monitored at regular intervals for up to 80 weeks. Sera from four of five patients with the acute form of the disease showed rapid falls in antigenemia, becoming antigen negative by week 14 (range, weeks 10 to 16). Sera from four patients with disseminated histoplasmosis showed falls in antigen levels; three of them became antigen negative by week 32; the fourth patient became negative by week 48. In contrast, antigen titers in four of six AIDS patients with the disseminated form of the disease remained positive throughout follow-up. Sera from only one patient who presented with the chronic form of the disease were analyzed, and this individual's serum became antigen negative by week 9. The inhibition ELISA is shown to be of particular use in the monitoring of non-AIDS patients with the acute and disseminated forms of the disease and may complement existing means of follow-up.

AIDS-Related Opportunistic Infections↗

PubMed1999

[Virtual cystoscopy of bladder neoplasms. Preliminary experience].

PURPOSE: We investigated the comparative sensitivity of virtual and conventional cystoscopy in patients with urinary bladder cancer. MATERIAL AND METHODS: Twelve patients (8 men and 4 women; mean age: 61 years, range: 49-73) with findings of bladder cancer at conventional cystoscopy were submitted to volumetric spiral CT of the urinary bladder. Before the examination, the urinary bladder was distended with 180-200 mL of air. CT findings were then sent to an independent workstation to generate interactive intraluminal views of the bladder. The findings of virtual cystoscopy were compared with those of conventional cystoscopy in 11 patients and with the findings of transurethral resection after urethrotomy in one patient. All lesions had pathologic confirmation. RESULTS: Eighteen (90%) of 20 masses detected on conventional cystoscopy were visualized with virtual cystoscopy. The latter allowed readers to identify 13 of 13 masses (100%) > 1 cm and only 5 of 7 (71%) < 1 cm; three 4-mm masses were missed. Although only a subjective evaluation of lesion size was possible on conventional cystoscopy, there seemed to be good agreement on mass size and site with both techniques. DISCUSSION: Cystoscopy plays a key role in the diagnosis of urinary bladder carcinoma. However cystoscopy is invasive, has a limited field of view and lacks an objective scale; moreover, it is not indicated in patients with severe urethral strictures or active vesical bleeding. In our study, virtual cystoscopy depicted all the masses > 1 cm, and a lesion in a diverticulum with a small opening. Virtual cystoscopy was also very useful in a patient with urethral stricture (who could no be submitted to conventional cystoscopy) where it showed the lesion before transurethral resection after urethrotomy. The virtual technique could also be complementary to conventional cystoscopy in evaluation of bladder base and anterior bladder neck, as well as for postchemotherapy follow-up. Unfortunately virtual cystoscopy does not allow biopsy of suspicious lesions.

Aged↗

PubMed1999

[Effect of an algae extract and several plant growth regulators on the nutritional value of potato (Solanum tuberosum L. var. gigant)].

Four commercial plant-growth (Biofol, Biozyme, Cytokin and Activol) and an extract from algae (AlgaEnzims) were applied at commercial doses in potatoes (S. tuberosum L. var. gigant) with and objective to evaluate its effect on nutritional value (dry-matter, water content, ashes, fat, protein, carbohydrates and assimilable fiber). These parameters were analyzed according to the Official Methods of Analysis (AOAC). The experimental design was in Random Blocks with 8 treatments and 4 replications with 32 lots in total. The statistical analysis was after Random Blocks for all bromatological analyses. The treatment algae in soil gave the highest ash content (6.20). Algae in soil (9.30), algae on foliage (8.90) and Cytokin (8.70) gave the highest values in protein as compared with test (6.20). Carbohydrate content was highest in Biofol (88.21), assimilable fiber was higher in algae in soil and on foliage (5.84) and lowest with Biofol (1.67). Highest fat content in the tuber was obtained with Biozyme and Cytokin and highest protein content with AlgaEnzims. With Activol the highest tuber production is obtained.

Crops, Agricultural↗

PubMed1998

[Aneurysm of the iliac artery in an elderly subject. Role of treatment with covered endoprosthesis].

BACKGROUND: Coated stents can be an alternative to open surgery for arterial aneurysms, particularly in patients with high operative risk. CASE REPORT: A 90-year-old man with advanced stage cardiopathy developed a 52 mm aneurysm of the iliac artery. Perioperative imaging (arteriography with marked catheter, CT-scan and endovascular ultrasonography) provided a precise description. The material used (PTFE coated thermal memory endoprosthesis, balloon in the hypogastric) provided effective exclusion. DISCUSSION: Endovascular treatment can be a useful alternative to open surgery for arterial aneurysm in the very elderly.

Aged↗

PubMed1998

Induction of apoptosis in murine macrophages by Mycobacterium tuberculosis is reactive oxygen intermediates-independent.

Infection with Mycobacterium tuberculosis induces apoptosis in murine macrophage lines. Resistant macrophages B10R (Bcgr) are more prone to undergo apoptosis than susceptible B10S (Bcgs) macrophages. Apoptosis and inhibition of intracellular growth of the mycobacteria seem to be dependent on the production of nitric oxide, since both can be reverted by aminoguanidine (AMG). Although B10R macrophages produce more superoxide anion than B10S macrophages after infection with M. tuberculosis, reactive oxygen intermediate (ROIs) scavengers did not affect uptake of 3H-uracil incorporation by the mycobacteria nor the induction of apoptosis. These results further suggest that both phenomena are dependent on the production of nitric oxide by the infected macrophages.

Animals↗

PubMed1998

Polycyclic aromatic hydrocarbon-DNA adducts in humans: relevance as biomarkers for exposure and cancer risk.

The methodology applied for DNA adducts in humans has become more reliable in recent years, allowing to detect even background carcinogenic adduct levels in environmentally exposed persons. Particularly, combinations of the various methods now allow the elucidation of specific adduct structures with detection limits of 1 adduct in 108 unmodified nucleotides or even lower. The quantification of polycyclic aromatic hydrocarbon-DNA (PAH-DNA) adducts in human tissues and cells has been achieved with a number of highly sensitive techniques: immunoassays and immunocytochemistry using polyclonal or monoclonal antisera specific for DNA adducts or modified DNA, the assay, and adduct identification using physicochemical instrumentation. The results summarized in this review show that PAH-DNA adducts have been detected in a variety of human tissues, including target organs of PAH- and tobacco-associated cancers. Although dosimetry has not always been precise, a large number of data now clearly show that lowering exposure to carcinogenic PAH results in decreasing PAH-DNA adduct levels. In most studies, however, bulk DNA of a certain tissue or cell type has been examined, and there were relatively few studies in which mutations as a consequence of DNA damage at specific genes have been investigated. Promising as these biomarker studies seem for epidemiology and health surveillance, future biomonitoring and molecular epidemiological studies should be directed to combine several endpoint measurements: i.e., adduct formation (preferably at specific sites), mutational spectra in cancer-relevant genes, and genetic markers of (cancer) susceptibility in a number of cancer-predisposing genes.

Animals↗

PubMed1998

The effect of parathion on mouse testicular and epididymal development cultured in chicken allantochorion.

Parathion is a widely used organophosphoric pesticide which has also been reported to interfere with mouse spermatogenesis. Moreover it has been related to prenatal toxicity in mammals. Sixteen A/ Snell mice were sacrificed at day 17 of pregnancy. Testes and epididymides of the male fetuses were implanted in the allantochorion of chicken eggs. Three experimental conditions of the egg injections were considered: Group I: 1 ml of parathion (0.5 mg/ml), Group II: 1 ml of parathion (1 mg/ml), and Group III: 1 ml distilled water (control group). The implanted subjects continued their development for 4 days (i.e. to complete the gestational period for mice). The cell proliferation and differentiation of the epithelial cells of the epididymis were evaluated with the use of the monoclonal antiproliferating cell nuclear antigen (PCNA-cyclin) antibody, and the AE1 keratin complex antibody. Parathion altered the allantochorion, as 15% of the chicken embryos died in Group I and 40% in Group II, vs. only 8% in controls (Group III). However, no malformations were seen in the surviving embryos. In the testicular implants, the seminiferous cords of Group I had the same cytological characteristics of germ and pre-Sertoli cells as the control, except for involuting Leydig cells. Contrarily, in the cases with higher doses of parathion (Group II), there was a complete disorganisation of the seminiferous cords and the interstitium. In some testes, hyaline degeneration of the seminiferous cords was observed. No cell proliferation was evident, and the epididymal morphology was apparently unaffected. Therefore, parathion seems to interfere with normal testicular differentiation. However, in spite of interstitial damage, the epididymal development seems unaltered. Since the epididymis is an androgen-dependent organ, it may be postulated that testosterone production is still sufficient to support epididymal development but not spermatogenic cell line differentiation.

Allantois↗

PubMed1998

Impact of adduct determination on the assessment of cancer susceptibility.

The characterization of genetic determinants for cancer susceptibility is important for understanding disease pathogenesis and for preventive measures. There is growing evidence that a group of predisposing polymorphic genes exists, such as those involved in carcinogen metabolism and repair, which may increase cancer in certain environmentally exposed subjects, even those exposed only to low levels of carcinogens. In developing preventive strategies, it is therefore necessary to identify these vulnerable members in our society, particularly those suffering from an unfortunate combination of high carcinogen exposure, cancer-predisposing genes and lack of protective (dietary) factors. Thus, molecular epidemiology faces the difficult task of analyzing carcinogen-exposed individuals for a combination of genotypes associated with cancer susceptibility. Once identified, combinations of cancer-predisposing genes can then be used as intermediate risk markers rather than taking cancer as an endpoint. In case-control studies, simultaneous measurements were carried out in each subject to determine exposure/early effect markers, e.g. polycyclic aromatic hydrocarbons (PAH)-DNA adducts, and susceptibility markers, e.g. genetic polymorphism, in drug-metabolizing enzymes related to cytochrome P450 1A1 (CYP1A1) and glutathione S-transferase (GSTM1) genes. The genotype dependence of human lung (+)-anti-benzo[a]pyrene diol-epoxide (BPDE)-DNA adducts in lung cancer patients was examined. BPDE-DNA adduct levels in bronchial tissue of smokers with high pulmonary CYP1A1 inducibility (by immunohistochemistry) and GSTM1 inactive were approximately 100-fold higher than in subjects with an active GSTM1 at similar smoking dose. Further genetic analyses confirmed that the combination of CYP1A1 homozygous mutants and GSTM1 inactive leads to high levels of BPDE-DNA adducts in human lung of smokers and white blood cells of PAH-exposed coke oven workers. Thus, BPDE-DNA adduct levels resulting from the "at risk" genotype combinations may serve as markers to identify high-risk subjects among smokers and individuals occupationally and/or environmentally exposed to PAH.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗

PubMed1998

[Pulmonary textiloma revealed by hemoptysis 12 years after thoracotomy].

INTRODUCTION: Pulmonary textiloma or retained surgical sponge is rare but can have detrimental consequences. Its diagnosis is difficult, even when using computerized tomography (CT) scan and is always a medical and legal problem. EXEGESIS: We report the case of a 46-year-old man with a history of pulmonary tuberculosis diagnosed by thoracotomy in 1986, who was admitted to hospital for hemoptysis. CT scan showed the existence of a pulmonary lesion. Clinical, radiological and fiberoptic endoscopy features mimicked an abscess or bronchiectasis. The patient underwent left inferior lobectomy. Anatomical findings led to the diagnosis of textiloma. CONCLUSION: This case shows the difficult in diagnosing pulmonary textiloma, even when using CT scan. Textiloma should be considered when an atypical pulmonary mass is found in a patient with past history of thoracotomy.

Follow-Up Studies↗

PubMed1998

Intestinal parasites of the grey fox (Pseudalopex culpaeus) in the central Peruvian Andes.

The intestines of 20 grey Peruvian foxes (Pseudalopex culpaeus) were examined for the presence of Echinococcus granulosus and other intestinal parasites. Echinococcus granulosus was not found in foxes but Taenia hydatigena and T. multiceps were found in 7 and 4 animals respectively. The grey fox may not be a suitable definitive host for E. granulosus. However, it may act as a sylvatic reservoir of T. hydatigena and T. multiceps in the central Peruvian Andes.

Animals↗

PubMed1998

Alcohol and drug use, and depression among Hispanic men in early adulthood.

Community research and clinical practice have shown that alcohol and drug use and depression are interrelated. Among Hispanics, acculturation may play a role in these relationships. To investigate these relationships as well as alcohol-related problems, we interviewed 288 Puerto Rican, Dominican, and Colombian men in early adulthood. No significant differences emerged in the proportions of abstainers across the three groups. Colombians drank significantly more frequently and had more alcohol-related problems than Dominicans. Dominicans were at least risk for and least likely to have alcohol-related problems. Puerto Ricans were much more likely to use drugs than the other Hispanic men. Drug use was associated with an increased likelihood of heavy drinking which, in turn, increased the risk of drug use and depression. Acculturation decreased the risk of drug use. Results are discussed in terms of implications for community psychology research and interventions.

Acculturation↗

PubMed1998

Genetic engineering of proteins with cell membrane permeability.

The discovery of methods for generating proteins with inherent cell membrane-translocating activity will expand our ability to study and manipulate various intracellular processes in living systems. We report a method to engineer proteins with cell-membrane permeability. After a 12-amino acid residue membrane-translocating sequence (MTS) was fused to the C-terminus of glutathione S-transferase (GST), the resultant GST-MTS fusion proteins were efficiently imported into NIH 3T3 fibroblasts and other cells. To explore the applicability of this nondestructive import method to the study of intracellular processes, a 41-kDa GST-Grb2SH2-MTS fusion protein containing the Grb2 SH2 domain was tested for its effect on the epidermal growth factor (EGF)-stimulated signaling pathway. This fusion protein entered cells, formed a complex with phosphorylated EGF receptor (EGFR), and inhibited EGF-induced EGFR-Grb2 association and mitogen-activated protein kinase activation.

3T3 Cells↗

PubMed1998

Activation of B cells by 1 microm particulate lysozyme or peptides: a Th-dependent pathway requiring CD40-CD40 ligand interaction.

Many antigens encountered by the immune system are included in complex structures such as bacteria or parasites. We previously developed an in vivo model to study the immunogenicity of particulate antigens, based on covalent linkage of proteins or peptides to 1 microm latex particles and showed that these antigens cannot be presented to MHC class II-restricted specific T cells by B cells. However, they induce strong CD4+ T cell responses when injected to mice without adjuvant. The present study demonstrates that four out of the five proteins tested did not stimulate antibody synthesis when linked to 1 microm microparticles, although a strong IgG production was induced by the same proteins administered in soluble form with adjuvant. In contrast, lysozyme and two synthetic peptides containing B and T cell viral epitopes induced strong and long-lasting specific antibody responses when linked to 1 micrometer synthetic beads. The isotypic pattern of antibodies induced by particulate lysozyme was similar to that induced by the soluble protein in alum. Studies using CD4+ T cell-depleted mice revealed that the induction of antibodies by particulate lysozyme strictly required Th cell activity. Moreover, the T-B cell cooperation involved in B cell activation by antigens linked to beads required CD40-CD40 ligand interaction. Thus, these particulate antigens provide a useful tool to study the mechanisms of induction of antibody response against complex bacterial or parasitic antigens. Moreover, they may represent attractive candidates to elaborate efficient new vaccines using short synthetic peptides.

Aluminum Hydroxide↗

PubMed1998

Conformational and topological requirements of cell-permeable peptide function.

Cell-permeable peptide import recently was developed to deliver synthetic peptides into living cells for studying intracellular protein functions. This import process is mediated by an N-terminal carrier sequence which is the hydrophobic region of a signal peptide. In this study, the conformational consequence of the interaction of cell-permeable peptides with different mimetic membrane environments was investigated by circular dichroism analysis. We showed that cell-permeable peptides adopted alpha-helical structures in sodium dodecyl sulfate (SDS) micelles or aqueous trifluoroethanol (TFE). The potency of these peptides in forming helical structures is higher in an amphiphilic environment (SDS) than in a hydrophobic environment (TFE), suggesting that some hydrophilic molecules associated with the cell membrane may be involved in peptide import. We also studied topological requirements of cell-permeable peptide function. We demonstrated that peptides containing the carrier sequence in their C-termini can also be imported into cells efficiently. This important discovery can avoid repetitious synthesis of the membrane-translocating sequence for peptides with different functional cargoes and is potentially useful for developing a cell-permeable peptide library. Finally, we showed that, when a retro version of the carrier sequence was used, the peptide lost its translocating ability despite retaining a high content of alpha-helical structure in mimetic membrane environments. This suggests that the propensity of peptides to adopt a helical conformation is required but not sufficient for cellular import and that other structural factors such as the side-chain topology of the carrier sequence are also important. Our studies together contribute to the more rational design of useful cell-permeable peptides.

3T3 Cells↗

PubMed1998

Antigenemia in patients with paracoccidioidomycosis: detection of the 87-kilodalton determinant during and after antifungal therapy.

Serological diagnosis and follow-up of paracoccidioidomycosis (PCM) patients have relied mainly on the detection of antibody responses by using techniques such as complement fixation (CF) and immunodiffusion. We recently described a novel inhibition enzyme-linked immunosorbent assay (inh-ELISA) which proved to be useful in the diagnosis of PCM via the detection of an 87-kDa determinant in patient sera (B. L. Gomez, J. I. Figueroa, A. J. Hamilton, B. Ortiz, M. A. Robledo, R. J. Hay, and A. Restrepo, J. Clin. Microbiol. 35:3278-3283, 1997). This test has now been assessed as a means of following up PCM patients. A total of 24 PCM patients, classified according to their clinical presentation (6 with the acute form of the disease, of whom two had AIDS, 12 with the multifocal form of the disease, and 6 with the unifocal form of the disease), were studied. The four human immunodeficiency virus-negative patients with acute PCM showed a statistically significant decrease in circulating antigen levels after the start of antifungal therapy. Antigen levels in this group became negative by our criteria (</=2.3 microgram/ml) before week 20 and remained so in three of four of these patients. In contrast, the two AIDS patients who also presented with the acute form of PCM showed no statistically significant decrease in circulating antigen levels even after 68 weeks of therapy. Taken together as a group, the patients with the multifocal form showed a statistically significant decrease in antigenemia after 28 weeks of therapy. In addition, five of six patients with the unifocal form became antigen negative by week 40. Antigen level decrease mirrored clinical cure in the majority of patients in all clinical groups; in contrast, measurement of anti-PCM antibodies via the CF test showed wide fluctuations in titers during the follow-up period. The inh-ELISA for the detection of the 87-kDa Paracoccidioides brasiliensis determinant would appear to be a valuable additional tool in the follow-up of PCM patients.

AIDS-Related Opportunistic Infections↗

PubMed1998

[Anti-sulfatide antibody titers in patients with chronic Chagas disease and other forms of cardiopathy].

A specific treatment for Chagas' disease has not yet been discovered, even though the condition is endemic in large parts of the Region of the Americas. Earlier studies have addressed the possibility that the sulfatide galactocerebroside in Trypanosoma cruzi behaves as an immunogen involved in the production of the high antisulfatide antibody levels found in patients with chronic infestation with the parasite. This may be an important factor in the pathogenesis of the cardiac symptoms and peripheral neuropathy seen in Chagas' disease, which is the most important cause of myocarditis in Central and South America and the second most important cause of heart failure in several of the countries located in these subregions. The present study was conducted in order to ascertain whether patients with Chagas' disease and other patients not afflicted with the ailment differ insofar as the presence of antibodies against sulfatide is concerned, and it describes antisulfatide antibody levels in 124 hospital patients (74 men and 50 women) between the ages of 15 and 94 who were in the cardiology unit of Vargas Hospital in Caracas from 1 July to 30 June 1995. Antisulfatide antibody titers were determined by means of enzyme-linked immunosorbent assays (ELISA), and the antigen employed was sulfatide cerebroside obtained from bovine brain tissue. Of the 124 patients under study, 39 (31.5%) suffered from Chagas' disease and had antisulfatide antibody levels higher than those detected in patients without Chagas (P = 0.0298) and in 28 seemingly healthy controls (P = 0.0035). Serum levels of antisulfatide antibodies in patients with other forms of heart disease were also compared with those seen in the control group, and significantly higher levels were found in patients with acute ischemic heart disease (P = 0.0049), rheumatic valvular heart disease (P = 0.0075), chronic ischemic heart disease (P = 0.0464) and bradiarrythmias (P = 0.0157), and significantly lower ones in subjects with hypertensive heart disease (P = 0.0367). These antibody levels showed no correlation with clinical or paraclinical variables indicative of the degree of cardiac compromise. Our results support the notion that antibodies against sulfatide may play a role in the pathogenesis of Chagas' cardiomyopathy and other forms of heart disease and should be further studied in an effort to determine their potential role in these processes.

Animals↗