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1.
Br J Educ Psychol ; 92(2): e12462, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34633063

RESUMO

BACKGROUND AND AIMS: This study focuses on individual differences in the math competencies of primary-school children in Germany. It considers whether or not there are Matthew or compensatory effects in math literacy and which factors and background characteristics of primary-school children can affect competence development. Despite the abundant research on this topic, the findings are often ambiguous, and studies in the German context are sparse. SAMPLE AND METHODS: We used the Starting Cohort 2 of the German National Educational Panel Study and a weighted multilevel mixed-effects panel regression for our analyses (N = 4,982). RESULTS: Our results revealed compensatory effects for low-achieving students in math literacy. There were also small gender differences, but lower achieving girls can close the gap with boys during primary school. With respect to the educational background of the parents, almost no longitudinal effects were observed. CONCLUSIONS: The results indicated that the joint primary-school period has a compensatory effect on lower performing students. However, higher achieving students retained their lead, implying that social inequalities persist to some extent.


Assuntos
Alfabetização , Estudantes , Criança , Feminino , Alemanha , Humanos , Masculino , Matemática , Fatores Socioeconômicos
2.
An Acad Bras Cienc ; 90(1 Suppl 2): 1073-1088, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29873669

RESUMO

N-acylhydrazone is an interesting privileged structure that has been used in the molecular design of a myriad of bioactive compounds. In order to identify new antinociceptive drug candidates, we described herein the design, synthesis, X-ray diffraction study and the pharmacological evaluation of a series of 3-amino-4-methylthiophene-2-acylcarbohydrazone derivatives (8a-t). Compounds were prepared in good overall yields through divergent synthesis from a common key intermediate and were characterized by classical spectroscopy methods. X-ray diffraction study was employed for unequivocal determination of the imine double bond stereochemistry. 8a-t were evaluated in vivo through oral administration using the classical writhing test in mice. N-acylhydrazone derivatives 8j and 8l displayed relative potency similar to dipyrone, highlighting them as promising analgesic lead-candidates for further investigation.


Assuntos
Analgésicos/síntese química , Anti-Inflamatórios/síntese química , Hidrazonas/síntese química , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Desenho de Fármacos , Hidrazonas/farmacologia , Espectrometria de Massas , Camundongos , Difração de Raios X
4.
Cell Physiol Biochem ; 36(6): 2237-49, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26279429

RESUMO

BACKGROUND/AIMS: Inhibition of p38 mitogen-activated protein kinase (p38 MAPK) is promising for the treatment of inflammatory disorders, however, the efficacy of p38 MAPK inhibitors in clinical trials is limited so far. Since functional sensitivity of p38 MAPK is commonly predicted by preclinical species, we systematically investigated interspecies differences including human tissue. METHODS: Ex vivo test models were established using whole blood and primary cells from different species such as mice, rats, pigs and humans to compare LPS-induced TNF-α inhibition of four different p38 MAPK reference inhibitors SB 203580, BIRB-796, Pamapimod, and a Losmapimod analogue as well as a proprietary imidazole-based p38 MAPK Inhibitor. RESULTS: All analysed p38 MAPK inhibitors resulted in significant inhibition of LPS-induced TNF-α release but with high interspecies differences for dose sensitivity. IC50 values from human whole blood and PBMC showed significant higher sensitivity towards p38 MAPK inhibition compared with data from pig and rat. CONCLUSION: Inhibition of TNF-α release by p38 MAPK inhibitors can be reliably identified in well-established laboratory species such as rat or mouse. However, our data indicate that animal models appear to be limited for valid prediction of the inhibitory potential for TNF-α release in humans. Thus, human tissues should be considered early in the drug development process of p38 MAPK inhibitors.


Assuntos
Lipopolissacarídeos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Fator de Necrose Tumoral alfa/sangue , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Células Cultivadas , Feminino , Humanos , Concentração Inibidora 50 , Masculino , Camundongos Endogâmicos C57BL , Inibidores de Proteínas Quinases/química , Ratos Endogâmicos Lew , Especificidade da Espécie , Sus scrofa , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Biol Chem ; 388(6): 561-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17552903

RESUMO

We recently demonstrated that heteromerization of innexins 2 and 3 from Drosophila melanogaster (Dm) is crucial for epithelial organization and polarity of the embryonic epidermis. Both innexins are thought to interact via their C-terminal cytoplasmic domains during the assembly of heteromeric gap junction channels. However, the mechanisms that control heteromeric versus homomeric channel formation are still largely unknown. Here we report the isolation of both non-modified and 2'-fluoro-2'-deoxy-modified RNA anti-innexin 2 aptamers by in vitro selection. The aptamers bind to a proximal epitope on the carboxyl-tail of Dm innexin 2 protein and specifically inhibit the heterologous interaction of innexin 2 and innexin 3 carboxyl-termini in vitro. These domain-specific inhibitors represent the first step towards functional studies focusing on the activity of these domains in vivo.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Conexinas/metabolismo , Proteínas de Drosophila/metabolismo , Sequência de Aminoácidos , Animais , Aptâmeros de Nucleotídeos/genética , Sequência de Bases , Conexinas/química , Proteínas de Drosophila/química , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína
6.
Mol Biol Cell ; 17(4): 1676-85, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16436513

RESUMO

Gap junctions consist of clusters of intercellular channels, which enable direct cell-to-cell communication and adhesion in animals. Whereas deuterostomes, including all vertebrates, use members of the connexin and pannexin multiprotein families to assemble gap junction channels, protostomes such as Drosophila and Caenorhabditis elegans use members of the innexin protein family. The molecular composition of innexin-containing gap junctions and the functional significance of innexin oligomerization for development are largely unknown. Here, we report that heteromerization of Drosophila innexins 2 and 3 is crucial for epithelial organization and polarity of the embryonic epidermis. Both innexins colocalize in epithelial cell membranes. Innexin3 is mislocalized to the cytoplasm in innexin2 mutants and is recruited into ectopic expression domains defined by innexin2 misexpression. Conversely, RNA interference (RNAi) knockdown of innexin3 causes mislocalization of innexin2 and of DE-cadherin, causing cell polarity defects in the epidermis. Biochemical interaction studies, surface plasmon resonance analysis, transgenesis, and biochemical fractionation experiments demonstrate that both innexins interact via their C-terminal cytoplasmic domains during the assembly of heteromeric channels. Our data provide the first molecular and functional demonstration that innexin heteromerization occurs in vivo and reveal insight into a molecular mechanism by which innexins may oligomerize into heteromeric gap junction channels.


Assuntos
Conexinas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Epitélio/embriologia , Morfogênese , Sequência de Aminoácidos , Animais , Caderinas/análise , Polaridade Celular/genética , Conexinas/análise , Conexinas/genética , Citoplasma/química , Citoplasma/metabolismo , Dimerização , Drosophila/citologia , Drosophila/metabolismo , Proteínas de Drosophila/análise , Proteínas de Drosophila/genética , Epitélio/química , Epitélio/metabolismo , Junções Comunicantes/metabolismo , Dados de Sequência Molecular , Morfogênese/genética , Estrutura Terciária de Proteína , Interferência de RNA
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