RESUMEN
The increase in vegetable consumption has underlined the importance of minimizing the risks associated with microbiological contamination of fresh produce. The critical stage of the vegetable washing process has proven to be a key point for cross-contamination and the persistence of pathogens. In this context, the agri-food industry has widely adopted the use of disinfectants to reduce the bacterial load in the wash water. Therefore, we conducted laboratory-scale experiments in order to demonstrate the antimicrobial activity of disinfectants used in the wash tank of agro-food industries. Different wash water matrices of shredded lettuce, shredded cabbage, diced onion, and baby spinach were treated with sodium hypochlorite (NaClO), chlorine dioxide (ClO2), and per-oxyacetic acid (PAA) at recommended concentrations. To simulate the presence of pathogenic bacteria, a cocktail of E. coli O157:H7 was inoculated into the process water samples (PWW) to determine whether concentrations of disinfectants inhibit the pathogen or bring it to a viable non-culturable state (VBNC). Hereby, we used quantitative qPCR combined with different photo-reactive dyes such as ethidium monoazide (EMA) and propidium monoazide (PMA). The results indicated that concentrations superior to 20 ppm NaClO inhibit the pathogen E. coli O157:H7 artificially inoculated in the process water. Concentrations between 10-20 ppm ClO2 fail to induce the pathogen to the VBNC state. At concentrations of 80 ppm PAA, levels of culturable bacteria and VBNC of E. coli O157:H7 were detected in all PWWs regardless of the matrix. Subsequently, this indicates that the recommended concentrations of ClO2 and PAA for use in the fresh produce industry wash tank do not inhibit the levels of E. coli O157:H7 present in the wash water.
RESUMEN
Introducción: El pilomatrixoma es un tumor benigno que afecta fundamentalmente a pacientes femeninas menores de 10 años. Se manifiesta como una masa sólida y encapsulada, situada profundamente en la dermis inferior y recubierto de piel normal; puede medir entre 3 y 30 milímetros. Objetivo: Informar las manifestaciones clínicas de este tumor que permiten llegar al diagnóstico de un pilomatrixoma. Presentación del caso: Se presenta el caso de un adolescente de 12 años de edad, que acude a consulta de dermatología del Hospital Andino de Chimborazo, con manifestaciones clínicas que permiten hacer el diagnóstico de pilomatrixoma. Conclusiones: El pilomaxitroma es un raro tumor que, aunque afecta frecuentemente a niñas menores de 10 años, también puede presentarse en pacientes mayores del sexo masculino. El estudio anatomopatológico resulta vital para realizar el diagnóstico de la enfermedad y una vez realizado dicho diagnóstico la excéresis del tumor es el procedimiento más adecuado(AU)
Introduction: Pilomatrixomais a benign tumor that mainly affects female patients under 10 years old. It manifests as a solid and encapsulated mass, located deep in the lower dermis and covered with normal skin; it can measure between 3 and 30 mm. Objective: To present the clinical manifestations that allow to reach the diagnosis of a pilomatrixoma. Case presentation: It is presented the case of a 12-year-old male adolescent, who attended the dermatology clinic in the Andean Hospital of Chimborazo, with clinical manifestations that allow the diagnosis of pilomatrixoma. Conclusions: Pilomaxitroma is a rare tumor that, although it frequently affects girls under 10 years of age, can also occur in older male patients. The anatomopathological study is vital to make the diagnosis of the disease and once performed the same exceresis of the tumor is the most appropriate procedure(AU)