RESUMEN
A doença celíaca é caracterizada pela intolerância ou hipersensibilidade à ingestão de prolaminas existentes no trigo, centeio, cevada e aveia. As proteínas do glúten do trigo são constituídas de aproximadamente 50% de prolaminas, denominadas gliadinas. O tratamento adotado para a doença celíaca é a dieta livre de glúten. A legislação brasileira determina que os produtos alimentícios industrializados devem apresentar a advertência da presença ou ausência de glúten na rotulagem. Duas amostras de referência estabelecidas em um estudo interlaboratorial e treze produtos alimentícios industrializados foram analisados para determinar a presença de glúten por meio de ensaio imunoenzimático comercial, ELISA técnica sanduíche, utilizando-se anticorpo monoclonal anti gliadina. O limite de detecção foi de 10 ppm (mg/kg). As amostras de referência revelaram resultados satisfatórios com boa exatidão. O glúten foi detectado nos produtos alimentícios que continham o referido componente declarado na rotulagem. O glúten não foi detectado nas amostras declaradas isentas de glúten, com exceção de uma amostra. O ensaio imunoenzimático utilizado discriminou as prolaminas não tóxicas apropriadas para os pacientes com doença celíaca, como os da farinha de arroz, milho, soja, mandioca, batata e batata doce, cujos ingredientes constavam nos dizeres de rotulagem. Os resultados apresentados evidenciam a viabilidade de uso de ELISA para a detecção de baixos teores de glúten em alimentos.
Asunto(s)
Ensayo de Inmunoadsorción Enzimática , Enfermedad Celíaca , Gliadina , GlútenesRESUMEN
OBJECTIVE: Previous reports suggest an increased susceptibility of diabetes patients to infections, but little information is available on possible underlying immunologic dysfunctions. The aim of this study was to evaluate humoral factors in pediatric patients with type 1 diabetes mellitus. METHODS: There were 66 diabetic patients (39 males:27 females; 5-17 yr) classified into two groups according to levels of glycohemoglobin (limit 9%): Group C - controlled (n = 33) and Group UC - uncontrolled (n = 33). We evaluated five patients in C and six in UC who reported previous infections. Immunologic analysis included measurement of plasma concentrations of immunoglobulins (Ig), C3, and C4 levels (turbidimetry); functional hemolytic assays for complement evaluation (CPH for classical and APH for alternative pathways), quantification of C4 isotypes C4A and C4B (ELISA), phagocytosis assays, measurement of bactericidal activity against Staphylococcus aureus, as well as tests of fungicidal capacity for Candida albicans. RESULTS: The UC Group had higher mean age, received higher insulin doses, and had higher concentrations of glycohemoglobin than the C Group. No significant differences in duration of the disease or nutritional conditions were detected between the groups. Lower IgA values in C (10/33) and lower IgG levels in UC (23/33) were detected, and there were inverse relationship with HbA1c values. Analysis of CPH, APH, C3, and C4 showed normal levels in both groups and no statistical correlation with the HbA1c. However, 9/33 children of the UC Group had decreased C3 values. C4B levels were below the normal range in 8/20 and correlated with higher HbA1c. Both phagocytic assays for S. aureus and Candida albicans were within normal limits. CONCLUSIONS: Low IgG concentrations and to some degree reduction in C4B levels were related to impaired metabolic control. No strong link between the immunological alterations was found in diabetic patients and the occurrence of infections.
Asunto(s)
Formación de Anticuerpos/fisiología , Diabetes Mellitus Tipo 1/inmunología , Susceptibilidad a Enfermedades/inmunología , Infecciones/inmunología , Adolescente , Niño , Preescolar , Complemento C3/metabolismo , Complemento C4/metabolismo , Femenino , Humanos , Inmunoglobulinas/sangre , Masculino , FagocitosisRESUMEN
Brazilian purpuric fever (BPF) is an acute disease caused by Haemophilus influenzae biogroup aegyptius; it is characterized by fever, purpura, and hypotensive shock and is usually fatal. The factors responsible for bacterial virulence and pathogenesis are poorly known. Hemagglutinins have been frequently associated with bacterial virulence, and, in the present study, hemagglutinating activity was detected in extracellular products from H. influenzae biogroup aegyptius strains isolated from patients with BPF. A 60-kilodalton (kDa) molecule absorbable by human O-type erythrocytes was identified by an immunoblot assay; a corresponding fraction was chromatographically purified, and its pathogenic effect was evaluated. Rabbits injected intravenously with either the whole bacterial extracellular product or the 60-kDa fraction showed reactions similar to those seen in patients with BPF: purpura, congestion, and fibrin thrombi in the inner organs. We suggest that this hemagglutinating factor is one of the major pathogenic components of BPF.