Enteropathogenic Escherichia coli modulates the virulence and pathogenicity of Entamoeba dispar.

Amoebiasis is a disease caused by Entamoeba histolytica, affecting the large intestine of humans and occasionally leading to extra-intestinal lesions. Entamoeba dispar is another amoeba species considered commensal, although it has been identified in patients presenting with dysenteric and nondysenteric colitis, as well as amoebic liver abscess. Amoebic virulence factors are essential for the invasion and development of lesions. There is evidence showing that the association of enterobacteria with trophozoites contributes to increased gene expression of amoebic virulence factors. Enteropathogenic Escherichia coli is an important bacterium causing diarrhea, with high incidence rates in the world population, allowing it to interact with Entamoeba sp. in the same host. In this context, this study aims to evaluate the influence of enteropathogenic Escherichia coli on ACFN and ADO Entamoeba dispar strains by quantifying the gene expression of virulence factors, including galactose/N-acetyl-D-galactosamine-binding lectin, cysteine proteinase 2, and amoebapores A and C. Additionally, the study assesses the progression and morphological aspect of amoebic liver abscess and the profile of inflammatory cells. Our results demonstrated that the interaction between EPEC and ACFN Entamoeba dispar strains was able to increase the gene expression of virulence factors, as well as the lesion area and the activity of the inflammatory infiltrate. However, the association with the ADO strain did not influence the gene expression of virulence factors. Together, our findings indicate that the interaction between EPEC, ACFN, and ADO Entamoeba dispar strains resulted in differences in vitro and in vivo gene expression of Gal/GalNAc-binding lectin and CP2, in enzymatic activities of MPO, NAG, and EPO, and consequently, in the ability to cause lesions.

The Stick Design Test on the assessment of older adults with low formal education: evidences of construct, criterion-related and ecological validity.

BACKGROUND: The assessment of visuospatial abilities is usually performed by drawing tasks. In patients with very low formal education, the use of these tasks might be biased by their cultural background. The Stick Design Test was developed for the assessment of this population. We aim to expand the test psychometric properties by assessing its construct, criterion-related and ecological validity in older adults with low formal education. METHOD: Healthy older adults (n = 63) and Alzheimer's disease patients (n = 92) performed the Stick Design Test, Mini-Mental State Examination, Digit Span Forward and the Clock Drawing Test. Their caregivers answered Personal Care and Instrumental Activities of Daily Living). Construct validity was assessed by factor analysis, convergent correlations (with the Clock Drawing Test), and divergent correlations (with Digit Span Forward); criterion-related validity by receiver operating characteristic curve analysis and binary logistic regression; and Ecological validity by correlations with ADL. RESULTS: The test factor structure was composed by one component (R 2 = 64%). Significant correlations with the Clock Drawing Test and Digit Span Forward were found, and the relationship was stronger with the first measure. The test was less associated with formal education than the Clock Drawing Test. It classified about 76% of the participants correctly and had and additive effect with the Mini-Mental State Examination (84% of correct classification). The test also correlated significantly with measures of ADL, suggesting ecological validity. CONCLUSIONS: The Stick Design Test shows evidence of construct, criterion-related and ecological validity. It is an interesting alternative to drawing tasks for the assessment of visuospatial abilities.

Executive dysfunction and low academic attainment in adolescent substance abusers with a history of maltreatment / Disfunção executiva e baixo desempenho escolar em adolescentes usuários de drogas com história de maus-tratos

OBJECTIVE: Substance abuse and maltreatment are highly associated with Executive Cognitive Function impairments, but very little is known about how symptoms of a condition known as Dysexecutive Syndrome may impact on real-life activities, especially in adolescents. This study investigated the presence of Executive Cognitive Function deficits in maltreated substance-abusing adolescents relative to healthy control subjects and analyzed the association between executive performance and educational attainment. METHOD: The sample consisted of 15 maltreated adolescent substance abusers and 15 non-maltreated healthy adolescents (controls). They were assessed by the Frontal Assessment Battery, composed of six subtests: Conceptualization, Mental flexibility, Motor programming, Sensitivity to interference, Inhibitory control, and Environmental autonomy. RESULTS: Maltreated adolescents did not differ from controls in sociodemographic variables such as age, ethnicity, and handedness. However, they performed significantly and importantly below controls in almost all domains of Executive Cognitive Function, including abstract abilities, cognitive flexibility, motor planning, and sensitivity to interference. Maltreated adolescents also completed fewer years of formal education vs. controls. The Frontal Assessment Battery total score correlated with educational attainment throughout the sample (r = 0.511; p < 0.01). CONCLUSION: Substance-abusing adolescents with a history of maltreatment performed more poorly vs. controls on a variety of measurements of executive functioning, and the results of the Frontal Assessment Battery were associated with educational attainment. Our results evidence a negative impact of dysexecutive symptoms on educational attainment in adolescents. Strategies focusing on neuropsychological rehabilitation may be relevant to help substance-abusing and maltreated adolescents to perform better at school and perhaps in life.

OBJETIVO: Abuso de substâncias e maus-tratos têm sido altamente associados com déficits nas funções executivas, porém pouco se conhece sobre o impacto da disfunção executiva nas atividades da vida real, especialmente em adolescentes. O objetivo deste estudo foi investigar a presença de déficits nas funções executivas em adolescentes abusadores de substâncias com histórico de maus-tratos, comparando-os com um grupo de jovens controles saudáveis, assim como analisar a associação entre o desempenho executivo e o nível de escolaridade dos participantes. MÉTODO: A amostra foi composta por 15 adolescentes abusadores de substâncias, vítimas de maus tratos e 15 adolescentes saudáveis, sem história de maus-tratos. Todos os participantes foram avaliados pela Bateria de Avaliação Frontal, composto por seis subtestes: Conceituação, Flexibilidade mental, Programação motora, Sensibilidade à interferência, Controle inibitório e Autonomia Ambiental RESULTADOS: Os adolescentes abusadores não diferiram dos controles saudáveis em variáveis sócio-demográficas, tais como idade, etnia e lateralidade. No entanto, apresentaram desempenho significativamente abaixo dos controles em quase todos os domínios das funções executivas, incluindo capacidade de abstração, flexibilidade cognitiva, planejamento motor e sensibilidade à interferência. Os adolescentes vítimas de maus tratos concluíram menos anos de educação formal do que os controles. A pontuação total da Bateria de Avaliação Frontal correlacionou com o nível de escolaridade, na amostra total (r = 0.511; p < 0.01). CONCLUSÃO: Os adolescentes abusadores de substâncias com histórico de maus-tratos apresentam prejuízos em várias medidas de Funções Executivas. Os resultados da Bateria de Avaliação Frontal associam-se com os anos completados de escolaridade. Nossos resultados evidenciam o impacto negativo da disfunção executiva no aproveitamento escolar em adolescentes. Estratégias com foco em reabilitação neuropsicológica podem ser relevantes para ajudar adolescentes abusadores de substâncias e vítimas de maus tratos a atingirem melhor aproveitamento na escola e, talvez, na vida como um todo.