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v. 17, n. 4, p. 223-226, out./dez. 2014. RESUMO:A maioria dos casos de doenças transmitidas por alimentos é causada por bactérias como Salmonella spp, Listeria monocytogenes, Campylobacter spp e Escherichia coli, entre outros. A contaminação decorre do consumo de alimentos contaminados preparados sob condições impróprias de higiene, manipulação e conservação. Para a detecção dessas bactérias em alimentos, o método convencional de isolamento é o mais utilizado, porém a técnica é demorada e laboriosa. A Reação em Cadeia da Polimerase (PCR) é um método rápido e sensível na detecção de agentes patogênicos e tem sido bastante estudada e gradativamente empregada nas indústrias de alimentos. O objetivo deste trabalho foi avaliar o limite de detecção da técnica de PCR, para Salmonella spp e L. monocytogenes. O limite para detecção das bactérias foram 2 e 5 UFC para Salmonella spp e L. monocytogenes, respectivamente, demonstrando uma boa sensibilidade da técnica de PCR. PALAVRAS-CHAVE: Biologia molecular. Diagnóstico. Listeriose. Salmonelose. DETECTION OF Salmonella spp AND Listeria monocytogenes THROUGH PCRABSTRACT: Most cases of foodborne illnesses are caused by bacteria such as Salmonella spp, Listeria monocytogenes, Campylobacter spp, Escherichia coli, among others. Contamination stems from the consumption of contaminated food prepared under improper hygiene, handling and storage conditions. For the detection of bacteria in food, the conventional isolation method is the most commonly used, but the technique is labor-intensive and time consuming. The Polymerase Chain Reaction (PCR) is a rapid and sensitive method for the detection of pathogen agents, and has been extensively studied and gradually used in food industries. The objective of this study is to evaluate the sensitivity of the PCR method for the detection of Salmonella spp and L. monocytogenes. The threshold for the detection of bacteria was 2 and 5 CFU for Salmonella spp and L. monocytogenes, respectively, presenting a high sensitivity to PCR. KEYWORDS: Isolation. Listeriosis. Molecular biology. Salmonellosis. DETECCIÓN DE Salmonella spp Y Listeria monocytogenes A TRAVÉS DE LA TÉCNICA DE PCRRESUMEN: La mayoría de los casos de enfermedades transmitidas por alimentos es causada por bacterias como la Salmonella spp, Listeria monocytogenes, Campylobacter spp y Escherichia coli, entre otros. La contaminación se produce por el consumo de alimentos contaminados y preparados bajo condiciones inadecuadas de higiene, manipulación y conservación. Para la detección de esas bacterias en alimentos, el método convencional de aislamiento es el más utilizado, pero la técnica es laboriosa y consume mucho tiempo. La Reacción en Cadena de la Polimerasa (PCR) es un método rápido y sensible para la detección de patógenos y ha sido ampliamente estudiado y gradualmente empleada en las industrias de alimentos. El objetivo de este estudio fue evaluar el límite de detección de la técnica de PCR, para L. monocytogenes y Salmonella spp. El límite para detección de las bacterias fueron ...

Anti-dentin autoantibodies are associated with inflammatory root resorption in permanent teeth and are modulated by dental trauma and orthodontic force. However, it is not known whether deciduous tooth trauma can stimulate the development of a humoral immune response against dentin. The aim of this study was to evaluate the levels of salivary SIgA reactivity against human dentin extract in young adults with a history of trauma in the primary dentition. A sample of 78 patients, aged 18 to 25, who had completed an early childhood (0 to 5 years old) caries prevention program years earlier at the Universidade Estadual de Londrina Pediatric Clinic, underwent radiographic examination and salivary sampling. Anti-dentin SIgA levels were analyzed by immunoenzymatic assay and Western blotting. Although dental trauma to deciduous teeth had occurred in 34 (43.6%) of the patients, no differences in SIgA levels were detected between individuals who had experienced trauma and those who had not (p > 0.05). Multivariate regression analysis showed no association between dental trauma and SIgA levels (p > 0.05). Patients with a history of deciduous trauma presented low levels of anti-dentin antibodies, associated with orthodontic root resorption (p < 0.05). Western blot analysis showed that salivary antibodies recognized a single band of approximately 45 kDa in dentin extract. We concluded that salivary SIgA recognizes a specific component of the dentin matrix and that anti-dentin antibodies were not triggered by trauma to primary teeth. However, trauma to deciduous teeth may down-modulate SIgA in response to orthodontic root response.