RESUMO
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. The polymorphic region of the parasites' chitinase genes was investigated by PCR, with the variation in amplicon sizes being used as a measure of the genetic variation among the isolates. The patients found infected with Entamoeba at the start of the study displayed varied patterns of infection clearance and re-infection. The analysis of the polymorphisms in the chitinase gene revealed seven polymorphic patterns in the E. histolytica isolates investigated and three in the E. dispar isolates. Many of the patients were each re-infected with Entamoeba at least once during the 12 months of follow-up. As seen in a previous study in Mexico, none of the E. histolytica-infected patients developed any clinical symptoms of invasive amoebiasis during the follow-up period. The results highlight the complexity of the host-parasite relationship in human amoebiasis.
Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Entamoeba/fisiologia , Entamebíase/epidemiologia , Infecções por HIV/parasitologia , Infecções Oportunistas Relacionadas com a AIDS/parasitologia , Adulto , Idoso , Animais , Quitinases/genética , Entamoeba/enzimologia , Entamoeba/genética , Entamebíase/genética , Feminino , Infecções por HIV/epidemiologia , Soropositividade para HIV , HIV-1 , Interações Hospedeiro-Parasita , Humanos , Estudos Longitudinais , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Prevalência , Estatística como AssuntoAssuntos
Entamoeba histolytica/classificação , Abscesso Hepático Amebiano/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Abscesso Hepático Amebiano/parasitologia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco , Distribuição por SexoRESUMO
BACKGROUND: Experimental evidences have suggested that a Th1 response is unable to eliminate H. pylori colonization; whereas a Th2 response, like the one induced by vaccination, reduces H. pylori infection in animal models. Some parasitic infections induce a polarized Th2 response, which theoretically would favor a reduced H. pylori prevalence. The aim of this work was to study the possible association between parasitic infections and H. pylori prevalence. MATERIALS AND METHODS: The study population included 120 children and 188 adults from a low socioeconomic level village. H. pylori prevalence was determined in serum by ELISA; parasitic infections were identified in feces by microscopic examination; and total serum IgE levels, as an indirect indicator of some parasitic infections, were determined by ELISA. RESULTS: In children, H. pylori prevalence was no different between those with and without intestinal parasitic infection. By contrast, adults with intestinal parasitic infection had a significantly lower H. pylori prevalence than adults without parasites (62.6% compared with 80.4%; p = 0.006, OR 2.45). Also in adults, but not in children, total IgE levels were significantly higher in those without H. pylori infection than in those with H. pylori infection (p < 0.001). CONCLUSIONS: Intestinal parasitic infections and serum IgE levels showed an age-dependent association with H. pylori prevalence. In adults, but not in children, intestinal parasitic infections and increased IgE levels where associated with a reduced H. pylori prevalence.
Assuntos
Infecções por Helicobacter/epidemiologia , Helicobacter pylori , Enteropatias Parasitárias/epidemiologia , Adolescente , Adulto , Criança , Infecções por Helicobacter/imunologia , Humanos , Imunoglobulina E/sangue , Enteropatias Parasitárias/imunologia , México/epidemiologia , PrevalênciaRESUMO
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. We found that the deleterious effects of formalin are both time and concentration dependent and may result from fragmentation of fixed DNA during its purification.
Assuntos
Entamoeba histolytica/genética , Fezes/parasitologia , Reação em Cadeia da Polimerase , Animais , DNA de Protozoário/efeitos dos fármacos , Entamoeba histolytica/isolamento & purificação , Fixadores , Formaldeído , Amplificação de Genes , Sensibilidade e Especificidade , Manejo de EspécimesAssuntos
Antígenos de Protozoários/imunologia , Portador Sadio/imunologia , Entamoeba histolytica/imunologia , Entamoeba/imunologia , Antígenos HLA/análise , Adolescente , Adulto , Animais , Portador Sadio/parasitologia , Estudos de Casos e Controles , Entamoeba/crescimento & desenvolvimento , Entamoeba histolytica/crescimento & desenvolvimento , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeAssuntos
Anticorpos Antibacterianos/biossíntese , Antígenos de Bactérias/administração & dosagem , Salmonella typhimurium/imunologia , Administração Oral , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/isolamento & purificação , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/isolamento & purificação , Imunidade nas Mucosas , Imunização , Esquemas de Imunização , Mucosa Intestinal/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Salmonelose Animal/imunologia , Salmonelose Animal/prevenção & controle , Fatores de TempoAssuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Antiprotozoários/biossíntese , Entamoeba histolytica/imunologia , Imunoglobulina A/biossíntese , Animais , Especificidade de Anticorpos , Antígenos de Protozoários/administração & dosagem , Hibridomas/imunologia , Imunidade nas Mucosas , Camundongos , Camundongos Endogâmicos BALB C , Nódulos Linfáticos Agregados/imunologiaAssuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Antiprotozoários/farmacologia , Entamoeba histolytica/fisiologia , Imunoglobulina A/farmacologia , Adenocarcinoma/patologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antiprotozoários/imunologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Colo/parasitologia , Neoplasias do Colo/patologia , Suscetibilidade a Doenças , Cães , Entamoeba histolytica/imunologia , Entamebíase/imunologia , Entamebíase/parasitologia , Gerbillinae , Imunoglobulina A/imunologia , Mucosa Intestinal/parasitologia , Rim , Camundongos , Camundongos Endogâmicos BALB C , Especificidade da Espécie , Células Tumorais CultivadasRESUMO
Antiamebic antibody titers, were investigated in the feces and sera of 30 adults patients with intestinal amoebiasis, during the first two weeks of disease. Also, 29 control samples of healthy adult subjects were studied. The objective of this study was to determine if the local or systemic IgG, IgM or IgA levels were modified during the early stages of acute intestinal amoebiasis, for this purpose ELISA technique was use. Anti E. histolytica antibody titers in fecal samples of patients were not statistically different from titers detected in control samples, however in both groups IgA and IgM titers were higher than IgG levels. In serum samples IgG antibody titers were 4 fold higher in patients than in control group. With a P less than 0.006. In the case of IgM and IgA differences observed between the two groups studied were not statistically significant. Our results suggest that titration of coproantibodies against E. histolytica have not predictive value for intestinal amoebiasis in areas, were amoebiasis is a endemic disease. On the other hand we observed a discrete increase in IgG levels in the group of patients.
Assuntos
Anticorpos Antiprotozoários/análise , Disenteria Amebiana/imunologia , Entamoeba histolytica/imunologia , Fezes/química , Doença Aguda , Adolescente , Adulto , Animais , Disenteria Amebiana/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina A/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos TestesAssuntos
Anticorpos Monoclonais/imunologia , Entamoeba histolytica/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Especificidade de Anticorpos , Antígenos de Protozoários/imunologia , Antígenos de Superfície/imunologia , Entamoeba histolytica/crescimento & desenvolvimento , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Proteínas de Membrana/imunologiaAssuntos
Entamoeba histolytica/genética , RNA/genética , Animais , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Antígenos de Protozoários/imunologia , Sistema Livre de Células , Entamoeba histolytica/imunologia , Entamebíase/imunologia , Soros Imunes , Biossíntese de Proteínas , Proteínas/genética , Proteínas/imunologia , RNA/isolamento & purificaçãoRESUMO
Different vaccination procedures to increase the mechanisms of host resistance to Nocardia brasiliensis were studied in mice. When mice were challenged in the footpad, 2 x 10(8) N. brasiliensis 20 days after footpad inoculation with either viable or killed N. brasiliensis, the mice demonstrated significant resistance to infection when compared with noninfected and nonimmunized mice. The degree of resistance seems to be correlated with the delayed-type hypersensitivity response in the vaccinated animals. Vaccination with another acid-fast bacilli, BCG, afforded both a mild protection and low DTH reactivity. Antibody levels to Nocardia were similar in either Nocardia- or BCG-treated groups indicating that they do not play an important role in resistance to infection by N. brasiliensis.
Assuntos
Hipersensibilidade Tardia , Micetoma/imunologia , Nocardiose/imunologia , Animais , Anticorpos Antibacterianos/análise , Formação de Anticorpos , Vacina BCG/uso terapêutico , Vacinas Bacterianas/uso terapêutico , Feminino , Imunidade Celular , Camundongos , Nocardia/imunologiaRESUMO
Listeria monocytogenes was used to study the rate of development, magnitude, and persistence of the antimicrobial resistance engendered by Nocardia brasiliensis infection in mice. The growth of Listeria in the liver and spleen was more effectively restricted in Nocardia-infected mice than in noninfected animals. The development of delayed-type hypersensitivity to the Nocardia antigen was closely correlated to the increased resistance to Listeria, suggesting that both properties are the consequence of a single immunological event. The antibacterial resistance was also demonstrated in vitro. The results of the foregoing studies indicate that the microbicidal ability of macrophages, very likely activated by cell-mediated immunity, in enhanced in mice infected with Nocardia.