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Germination and early seedling development are critical for successful stand establishment of plants. Following germination, the cotyledons, which are derived from embryonic tissue, emerge from the seed. Arabidopsis seedlings at post-germinative stages are supported mainly by the supply of nutrition from the cotyledons until vegetative leaves emerge and initiate photosynthesis. The switch to autotrophic growth is a significant transition at the post-germinative stage. Here, we provide evidence that down-regulation of SQUAMOSA PROMOTER-BINDING PROTEIN LIKE13 (SPL13) by microRNA156 (miR156) plays an important role in the regulation of the post-germinative switch from the cotyledon stage to the vegetative-leaf stage. Silent mutations created in the SPL13 sequence in the region that is complementary to the miR156 sequence caused the deregulation of the mutant form of SPL13 (mSPL13) mRNA from miR156. Mutant seedlings over-accumulated miRNA-resistant messages and exhibited a delay in the emergence of vegetative leaves compared to wild-type seedlings. The delay was not observed in control transgenic plants expressing nonmutated SPL13, indicating that the phenotype was caused specifically by the silent mutations and deregulation of SPL13 from miR156. Characterization of the SPL13 promoter indicated that this gene is expressed mainly in the hypocotyl and affects leaf primordium development. These results suggest that the repression of SPL13 by miR156 is essential for normal post-germinative growth in Arabidopsis. [ABSTRACT FROM AUTHOR]

The Asthma Therapy Assessment Questionnaire (ATAQ) for children and adolescents was developed to assist clinicians and health plans to identify children at risk for adverse outcomes of asthma. ATAQ is a brief, 20-item parent-completed questionnaire that generates indicators of potential care problems in several categories, including symptom control, behavior and attitude barriers, self-efficacy barriers, and communication gaps. This paper describes testing of the internal consistency and construct validity of the instrument. A cross-sectional mail survey with telephone follow-up was conducted with parents of 434 children aged 5-17 years being treated for asthma and enrolled in three managed care organizations in the Midwestern and Northeastern United States. ATAQ scales were evaluated using correlations with measures of health status, asthma impact, and healthcare utilization. ATAQ demonstrated good internal consistency and the hypothesized relationships to corresponding measures from existing instruments. Asthma control was significantly associated with measures of physical health, psychosocial health, resource use, and family impact. "Shared decision making," an indicator of patient-provider communication and involvement of the parent and child in developing asthma management plans, was significantly and positively associated with symptoms and parental satisfaction. Other ATAQ components showed similar associations. ATAQ appears to have satisfactory measurement properties and is ready for use to identify patients who might benefit from further disease management efforts or medical attention.