Peptide-DNA conjugates as tailored bivalent binders of the oncoprotein c-Jun.

We describe a ds-oligonucleotide-peptide conjugate that is able to efficiently dismount preformed DNA complexes of the bZIP regions of oncoproteins c-Fos and c-Jun (AP-1), and therefore might be useful as disrupters of AP-1-mediated gene expression pathways.

Ras GTPase-activating protein regulation of actin cytoskeleton and hyphal polarity in Aspergillus nidulans.

Aspergillus nidulans gapA1, a mutation leading to compact, fluffy colonies and delayed polarity establishment, maps to a gene encoding a Ras GTPase-activating protein. Domain organization and phylogenetic analyses strongly indicate that GapA regulates one or more "true" Ras proteins. A gapADelta strain is viable. gapA colonies are more compact than gapA1 colonies and show reduced conidiation. gapADelta strains have abnormal conidiophores, characterized by the absence of one of the two layers of sterigmata seen in the wild type. gapA transcript levels are very low in conidia but increase during germination and reach their maximum at a time coincident with germ tube emergence. Elevated levels persist in hyphae. In germinating conidiospores, gapADelta disrupts the normal coupling of isotropic growth, polarity establishment, and mitosis, resulting in a highly heterogeneous cell population, including malformed germlings and a class of giant cells with no germ tubes and a multitude of nuclei. Unlike wild-type conidia, gapADelta conidia germinate without a carbon source. Giant multinucleated spores and carbon source-independent germination have been reported in strains carrying a rasA dominant active allele, indicating that GapA downregulates RasA. gapADelta cells show a polarity maintenance defect characterized by apical swelling and subapical branching. The strongly polarized wild-type F-actin distribution is lost in gapADelta cells. As GapA-green fluorescent protein shows cortical localization with strong predominance at the hyphal tips, we propose that GapA-mediated downregulation of Ras signaling at the plasma membrane of these tips is involved in the polarization of the actin cytoskeleton that is required for hyphal growth and, possibly, for asexual morphogenesis.

New developments in the synthesis of oligonucleotide-peptide conjugates.

The stability of oligodeoxynucleotides to trifluoroacetic acid is studied. Pyrimidine oligonucleotides were stable in the conditions used for the removal of t-butyl groups. Oligonucleotide-3'-peptide conjugates carrying pyrimidine oligonucleotides are prepared stepwise using peptide-supports and Fmoc, t-butyl strategy. Using this strategy we have prepared an oligonucleotide-peptide conjugate containing as peptide the leucine-rich fragment of FOS, a transcription factor involved in many important cellular processes. This conjugate has a long peptide sequence with a large number of trifunctional amino acids.

Estudo da anatomia interna dos pré-molares: revisão de literatura / The root and root canal morphology of the human premolar: a literature review

Com a intenção de reforçar a estreita relação existente entre o conhecimento da anatomia interna e a obtenção do sucesso no tratamento endodôntico, são relatadas aqui características da anatomia interna presentes no grupo dental dos pré-molares.Revisão de literatura: as alterações morfológicas quando desconsideradas podem dificultar a terapia endodôntica. A resolução de casos com anatomia incomum exige consequentemente, mudanças no método de diagnóstico, assim como no tratamento.Conclusão: a identificação, e, portanto, o tratamento satisfatório de raízes e canais diferenciados, diminui a persistência dos sinais e sintomas, reduzindo, assim as possíveis causas de um retratamento...

Intended to illustrate and reinforce the close link between knowledge of internal anatomy and the achievement of success in endodontic treatment, are reported here characteristic of the internal anatomy in the dental group of premolars.Literature review: the morphological changes when discarded can complicate the endodontic therapy. The resolution of cases with unusual anatomy requires, therefore, changes in the method of diagnosis, and treatment.Conclusion: the identification and, therefore, the satisfactory treatment of roots and different canals, reduces the persistence of signs and symptoms, reducing thus, the possible causes of a retreatment...

Análise radiográfica do preenchimento de canais laterais por quatro diferentes técnicas de obturação / Radiographic analysis of the lateral canals filling by four different obturation techniques

Muitas técnicas de obturação têm sido desenvolvidas, especificamente com o objetivo de aumentar a qualidade do selamento apical com a associação guta-percha/cimento obturador. O objetivo desta pesquisa foi avaliar, por mei do exame radiográfico, a qualidade do preenchimento de canais laterais de 60 dentes extraídos, utilizando cimento de Grossman conjuntamente com a aplicação de quatro diferentes técnicas obturadoras: McSpadden, híbrida de Tagger, Thermafil e condensação lateral. Os resultados foram obtidos com a análise das radiografias finais, em que se observou a superioridade do sistema Thermafil em relação às demais técnicas testadas para o preenchimento dos canais laterais

Many obturation techniques have been developed, specifically with the purpose of increasing the quality of the apical sealing with theassociation gutta-percha/sealer. The aim of this study was to evaluate,by means of radiographic exam, the sealing quality of 60 extracted teeth lateral canals, using Grossman sealing and four types of obturation techniques: McSpadden, Tagger hybrid technique, Thermafil andlateral condensation. The results were obtained with the analysis ofthe final radiographs, in which could be observed that Thermafil had superiority in relation to the other techniques when testing the sealing of lateral canals.