RESUMO
Establishing validated science programs for students with or at risk for learning disabilities requires testing treatment effects and exploring differential response patterns. This study explored whether students' initial mathematics and reading skills influenced their treatment response to a whole-class, second-grade science program called Scientific Explorers (Sci2). The original Sci2 study employed a cluster randomized controlled design and included 294 students from 18 second-grade classrooms. Differential effects of the program by initial mathematics and reading skill levels were not observed for an interactive science assessment and a distal science outcome measure. However, based on initial reading skill levels, moderation results were found on a science vocabulary measure, suggesting the effects of Sci2 were greatest for students with higher initial reading skills. Similar results were found using initial mathematics skill levels as a predictor of differential response such that students with higher mathematics skills reaped stronger treatment effects on the vocabulary measure. Further, we found initial mathematics skills also influenced outcomes on the proximal science content assessment, where students with higher initial mathematics skills led to higher outcomes. Overall, findings suggest Sci2 produced robust effects for all students (g = 0.24-1.23), regardless of initial skill proficiencies. Implications for exploring differential response in science intervention research are discussed.
RESUMO
The skin secretions of Crinia signifera, C. riparia and C. deserticola contain bioactive disulfide-containing peptides. Signiferin 1 (RLCIPYIIPC-OH) from C. signifera and C. deserticola) contracts smooth muscle at a concentration of 10(-9) M, and effects proliferation of lymphocytes at 10(-6) M. In contrast, riparin 1.1 (RLCIPVIFC-OH) and riparin 1.2 (FLPPCAYKGTC-OH) from C. riparia show lymphocyte activity but do not contract smooth muscle. The lymphocyte and smooth muscle activities involve CCK2R. 3D structures of signiferin 1 and riparin 1.1 have been established using 2D NMR methods: these studies show significant differences in the shapes of the disulfide rings and with the orientations of the N-terminal residues. cDNA cloning establishes that the pre sections of the precursor pre-pro-riparin 1.4-1.6 peptides are different from the conserved pre regions of disulfide-containing antimicrobial peptides from species of the genus Rana found in the northern hemisphere and caerin antimicrobial peptides isolated from Australian tree frogs of the genus Litoria. This suggests that (i) either that riparins 1 have converged to similar structure and function to the ranid and hyloid prepropeptides which were lost initially from the myobatrachid lineage, or (ii) the prepropeptides in all three groups were derived from a single ancestral form that has remained relatively conserved in the hyloid and ranoid lineages but has undergone substantial divergent evolution in the myobatrachids.
Assuntos
Proteínas de Anfíbios/química , Proteínas de Anfíbios/metabolismo , Anuros/fisiologia , Neuropeptídeos/química , Neuropeptídeos/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Sequência de Aminoácidos , Proteínas de Anfíbios/genética , Proteínas de Anfíbios/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Anuros/genética , Sequência de Bases , Clonagem Molecular , Primers do DNA/genética , DNA Complementar/genética , Dissulfetos/química , Evolução Molecular , Ativação Linfocitária/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Molecular , Contração Muscular/efeitos dos fármacos , Neuropeptídeos/genética , Neuropeptídeos/farmacologia , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Peptídeos/genética , Peptídeos/farmacologia , Conformação Proteica , Pele/metabolismoRESUMO
Five healthy adult female first-generation hybrid tree frogs were produced by interspecific breeding of closely related tree frogs Litoria splendida and L. caerulea in a cage containing large numbers of males and females of both species. Phylogenetic analysis of mitochondrial DNA sequences established the female parent to be L. splendida. The peptide profile of the hybrid frogs included the neuropeptide caerulein, four antibiotics of the caerin 1 family and several neuronal nitric oxide synthase inhibitors of the caerin 1 and 2 classes of peptides. The skin secretions of the hybrids contained some peptides common to only one parent, some produced by both parental species, and four peptides expressed by the hybrids but not the parental species.