ABSTRACT
Parasite M17 leucine aminopeptidases (LAPs) have been associated with critical roles in different key functions such as the nutrition, migration, and invasion of the natural host. Native or recombinant LAP used as a vaccine antigen has proved effective to elicit protection against Fasciola hepatica infection in sheep, pointing to potential vaccine candidates against fascioliasis in ruminant species. Previously, the FhLAP1, abundantly secreted in vitro by the mature adult parasite was used as a vaccine antigen obtaining promising protection results against F. hepatica challenge in small ruminants. Here, we report the biochemical characterization of a second recombinant LAP (FhLAP2) associated with the juvenile stage of F. hepatica. FhLAP2 showed aminopeptidase activity using different synthetic substrates, including leucine, arginine, and methionine and was increased in the presence of Mn+ 2 and Mg+ 2. The activity was inhibited by bestatin, 1,10-phenanthroline, and EDTA, specific inhibitors of aminopeptidase and/or metalloproteases. Finally, the recombinant FhLAP2 functional form was tested in combination with Freund's incomplete adjuvant in an immunization trial in mice followed by an experimental challenge with F. hepatica metacercariae. The immunization with FhLAP2/FIA resulted in a significant reduction of parasite recovery compared to control groups. The immunized group elicited total specific IgG and subclasses IgG1 and IgG2 antibody responses. This study highlights the potential of a new candidate vaccine formulation with potential applications in natural ruminant hosts, especially those targeting the juvenile stage.
Subject(s)
Fasciola hepatica , Fascioliasis , Sheep Diseases , Vaccines , Sheep , Mice , Animals , Fascioliasis/prevention & control , Fascioliasis/veterinary , Leucyl Aminopeptidase/chemistry , Leucine , Antibodies, Helminth , Sheep Diseases/parasitologyABSTRACT
El avance en las terapias oncológicas trae consigo un aumento progresivo en la sobrevida de los niños con cáncer, lo que implica la necesidad de un abordaje integral en el cuidado de estos pacientes. En Chile no existen reportes formales sobre los efectos psicosociales en sobrevivientes de cáncer infantil. Con el fin de identificar el impacto psicosocial y calidad de vida, se realiza una revisión de literatura utilizando las bases de datos PubMed, Proquest Nursing Journals, EBM Reviews, Scielo y CINHAL. La búsqueda comprende textos completos de los últimos cinco años, en inglés y español. Se encuentran 91 artículos y se seleccionan 22 investigaciones cuantitativas y cualitativas. Los resultados muestran que el impacto psicosocial se manifiesta principalmente por baja autoestima e incertidumbre hacia el futuro, así como problemas de relaciones sociales en las áreas de empleo e independencia financiera, rendimiento académico y relaciones de pares y matrimonio las que se encuentran relacionadas con baja percepción en la calidad de vida. Por otra parte se observa mejor aceptación de sus limitaciones, adaptabilidad a las situaciones negativas y madurez psicológica. La experiencia de vivir con cáncer genera múltiples efectos en la vida de los niños sobrevivientes a nivel psicosocial. En Chile es fundamental que la enfermera, profesional encargada de la gestión del cuidado, realice seguimiento integral a los pacientes pediátricos desde el diagnóstico, promoviendo el autocuidado para mejorar su calidad de vida.
The advances in cancer therapies bring a progressive increase in survival of cancer among children, which implies the need for a more holistic approach of care for these patients. In Chile there are no formal reports about the psychosocial effects of childhood cancer survivors. To identify the psychosocial impact and quality of life, a literature review was done using databases: PubMed, Proquest Nursing Journals, EBM Reviews, Scielo and CINAHL. The search limits included: full texts of the last five years in English and Spanish. Ninety-one articles were found and 22 of them were selected using the criteria of having a quantitative or qualitative design. The results demostrate that the psychosocial impact is manifested mainly by low self-esteem and uncertainty toward the future, and problems of social relationships in areas such as employment, financial independence, academic performance and marriage, and relating to peers, which were related to low perceived quality of life. Also, greater acceptance of limitations, adaptability to negative situations and psychological maturity were identified. The experience of living with cancer produces multiple psychological effects in the lives of surviving children. In Chile, it is essential that the nurses in charge of child oncology care, management make a follow up of pediatric patients, beginning from the time of diagnosis, promoting self-care, and thereby improving quality of life.