Periodicity and patterns of Entamoeba histolytica and E. dispar infection in HIV+/AIDS patients in Mexico.

In a 12-month longitudinal study, a cohort of Mexican HIV+/AIDS patients was checked several times for Entamoeba infection, with the parasites identified, as E. histolytica or E. dispar, using PCR.

Functional diversity of T-cell subpopulations in subacute and chronic hypersensitivity pneumonitis.

Rationale: Hypersensitivity pneumonitis (HP) exhibits a diverse outcome. Patients with acute/subacute HP usually improve, whereas patients with chronic disease often progress to fibrosis. However, the mechanisms underlying this difference are unknown.

Infection by human immunodeficiency virus-1 is not a risk factor for amebiasis.

The purpose of this study was to determine whether HIV-1 infected patients in our community were more susceptible to Entamoeba histolytica and Entamoeba dispar infection than non-HIV-infected individuals. The prevalence and frequency of invasive amebiasis was determined in 203 HIV+/AIDS subjects and 140 close relatives or sexual partners, all of whom were HIV-. Anti-E.

High prevalence rate of Entamoeba histolytica asymptomatic infection in a rural Mexican community.

The frequency of Entamoeba histolytica and Entamoeba dispar infection was analyzed in a rural community in the state of Morelos, Mexico, using polymerase chain reaction (PCR). Sociodemographic variables as risk factors for the infection were assessed. Results highlighted the number of individuals with intestinal parasites (43.

Entamoeba histolytica and/or Entamoeba dispar: infection frequency in HIV+/AIDS patients in Mexico city.

The objective of this work was to evaluate the frequency of Entamoeba histolytica/Entamoeba dispar intestinal infection in HIV+/AIDS subjects and their HIV- close relatives or sexual partners. Enteric parasites were investigated in stool samples by microscopic examination and E. histolytica and E.

Entamoeba histolytica and Entamoeba dispar: prevalence infection in a rural Mexican community.

The frequency of Entamoeba histolytica and Entamoeba dispar infection was analyzed in a rural community in the state of Morelos, Mexico, through PCR technique by using specie specific primer. The E. histolytica specie was detected in 33 of 290 analyzed stool samples (11.

E. dispar strain: analysis of polymorphism as a tool for study of geographic distribution.

The intra-species polymorphism of E. histolytica and E. dispar species in endemic area is an important tool for geographic distribution and spread mechanism studies.

Calreticulin-like molecule in trophozoites of Entamoeba histolytica HM1:IMSS (Swissprot: accession P83003).

In this work, we report the partial sequence of a 51 kDa protein of Entamoeba histolytica that is highly immunogenic in humans. Partial sequencing of the N-terminal end showed that 18 of the first 20 amino acid residues of the protein were identified uniquely, indicating that the final product was a homogeneous protein preparation. The N-terminal sequence that was found was: KVYFEETFENGWKXIWSKW.

Defective production of reactive oxygen intermediates (ROI) in a patient with recurrent amebic liver abscess.

Previously, we reported the case of a man in the fourth decade of life afflicted with three independent episodes of amebic liver abscesses over a period of 4 years. Previous evidence has indicated that the cellular immune response is involved in protection against recurrent invasive amebic infection, and macrophage-mediated effector mechanisms appear important for host resistance to Entamoeba histolytica infection. The aim of the present work was to investigate locomotor activity and oxidative burst function of peripheral mononuclear cells of this individual after healing of the third amebic liver abscess.

Persistence of secretory antiamoebic antibodies in patients with past invasive intestinal or hepatic amoebiasis.

In the present work, it was demonstrated that in amoebic dysentery and amoebic liver abscess patients, the secretory response is long-lasting (> 12 months); and 50% of amoebic dysentery patients developed circulating antiamoebic IgG in comparison with 100% of amoebic liver abscess individuals. A total of 83% of these individuals developed high levels of serum anti-Entamoeba histolytica IgA. However, only 10.

HLA characterization in adult asymptomatic cyst passers of Entamoeba histolytica/E. dispar.

The present work aimed at studying the possible association of HLA antigens with Entamoeba histolytica/E. dispar asymptomatic infection in a Mexican mestizo population. A case-control design was selected for evaluation of the role of genetic markers in parasite infection.

The effect of formalin fixation on the polymerase chain reaction characterization of Entamoeba histolytica.

Formalin fixation is the most common storage, transportation and preservation method for stool samples. However, fixation dramatically reduces our ability to extract from stool samples DNA that is a suitable template for polymerase chain reaction (PCR)-based diagnostic tests. In this study we evaluated the effects of formalin concentration and of the time stored in fixative on the success of PCR amplification.

Prospective study of Entamoeba dispar infection in a cohort of mothers and their infants: relationship to serum antibody response.

The sera of cohorts of newborn infants and their mothers, characterized as cyst passers of Entamoeba with nonpathogenic zymodemes (E. dispar) and seropositive for amoebic antigens, were analyzed. Both cohorts were followed for a period of 12 months by microscopic examination of feces and determination of serum anti-amoebic antibody titers using the indirect hemagglutination assay.

Human cell-mediated immune responses to antigenic fractions of Salmonella typhi.

The proliferative responses of peripheral blood mononuclear cells of 10 subjects that had typhoid fever, and healthy volunteers without history of typhoid fever or immunization against disease, were analysed with antigen fractions from two protein extracts of Salmonella typhi. Fractions from each extract were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) electrophoresis, transferred to nitrocellulose filters by electroblotting and processed to obtain antigen-bearing nitrocellulose particles for use in lymphocyte cultures. Although the individual proliferative responses were heterogeneous we identified two main immunogenic regions of 29-32 10(3) MW and 45-56 x 10(3) MW for both extracts.

Cellular immune response to fractionated avian antigens by peripheral blood mononuclear cells from patients with pigeon breeder's disease.

Pigeon breeder's disease (PBD), a form of hypersensitivity pneumonitis caused by repeated inhalation of antigens of pigeon origin, is characterized by a diffuse inflammation of the lower respiratory tract. Although a variety of immunologic and nonimmunologic mechanisms have been described in the development of the disease, the pathogenesis is still far from clear. In this study we analyzed the T-lymphocyte proliferative response to a variety of avian antigens with use of peripheral blood mononuclear cells from 11 patients who had PBD and 10 healthy volunteers.

Salmonella typhimurium infection in mice: lymphoproliferative responses to fractionated protein antigens.

The proliferative response of spleen cells of mice immunized with S. typhimurium by the oral route was analyzed using antigen fractions from a protein extract of the bacteria. Mice that survived the challenge with a virulent strain of Salmonella and normal mice were also studied.

Entamoeba histolytica: antibody response to recent and past invasive events.

Sero-epidemiological data from endemic amoebiasis areas are difficult to evaluate because the serology of individuals affected by an active process of Entamoeba histolytica tissue invasion is, at present, almost impossible to distinguish from that of individuals who have had an invasive event in the past. The present study compares serum antigenic recognition frequencies among three groups of individuals with different infective conditions: amoebic liver abscess patients; asymptomatic cyst passers; and individuals who have had amoebic liver abscess from one to three years before the study. Control groups consisted of Mexican and Canadian healthy adults.