Carmen Isabel Gómez García

Differential effects of abscisic acid and methyl jasmonate on endoproteinases in senescing barley leaves

Endoproteinase activity was analyzed in chloroplasts isolated from barley leaf segments incubated in the dark with various hormonal senescence effectors. As a control, the endoproteinase activity of the supernatant fraction obtained during chloroplast preparation was also analyzed. Measured against azocaseine as substrate, the endoproteinase activity in chloroplasts increased 18 fold during the induction of senescence. This rise in activity was inhibited by kinetin (the activity increased only 10 fold) and very strongly stimulated by abscisic acid (ABA) (117 fold) and methyl jasmonate (Me-JA) (57 fold). Although less so, the endoproteinase activity of the supernatant fraction, mainly vacuolar and with acid pH optimum, was affected in the same way by all three effectors. Among the five endoproteinases (EC) found in chloroplasts, EC2 and EC4 were induced after incubation in water. ABA increased the levels of EC2 and EC4 (5 fold), and induced the development of EC3 and EC5, while Me-JA totally inhibited EC2 and EC4, and induced the development of EC1. At least one of the endoproteinases, EC2, is synthesized in chloroplasts. Among the six endoproteinases found in the supernatant fraction (E), E1, E2, E3 and E5, which are very probably extrachloroplastic endoproteinases, are stimulated by ABA to varying degrees. However, Me-JA stimulates E1 to a greater extent and totally inhibits E3. The differential effects of ABA and Me-JA on chloroplast and supernatant fraction endoproteinases suggest different action mechanisms for both senescence promotors.

Diseño y validación de un cuestionario sobre conocimientos y hábitos en higiene corporal infantil (HICORIN

OBJECTIVE To develop and validate a questionnaire on the integral assessment of the habits and knowledge in personal hygiene in children between 7 to 12 years old in the educational, social and health environment. DESIGN Cross-sectional study for the validation of a questionnaire. LOCATION One primary and secondary school and one childrens home in the Region of Murcia, Spain. PARTICIPANTS A total of 86 children were included (80 from a primary and secondary school; 6 from a childrens home), as well as 7 experts. MAIN MEASUREMENTS Content validation by experts; qualitative assessment; identify difficulties related to some questions, item response analysis, and test-retest reliability. RESULTS After the literature search, 20 tools that included items related to child body hygiene were obtained. The researchers selected 34 items and drafted 48 additional ones. After content validity by the experts, the questionnaire (HICORIN®) was reduced to 63 items, and consisted of 7 dimensions of child personal hygiene (skin, hair, hands, oral, feet, ears, and intimate hygiene). After with the children some terms were adapted to improve their understanding. Only two items had non-response rates that exceeded 10%. The test-retest showed that 84.1% of the items had between very good and moderate reliability. CONCLUSIONS HICORIN® is a reliable and valid instrument that integrally assesses the habits and knowledge in personal hygiene in children between 7-12 years old. It is applicable in educative and social and health environments and in children from different socioeconomic levels.