Targeted delivery of antisense oligonucleotides by molecular conjugates

Antisense oligonucleotides efficiently inhibit gene expression in vitro; however, the successful therapeutic application of this technology in vivo will require the development of improved delivery systems. In this report we describe a technique that efficiently delivers antisense oligonucleotides into cells using molecular conjugates. This technique, which was initially developed for the delivery of eukaryotic genes, is based on the construction of DNA-protein complexes that are recognized by the liver-specific asialoglycoprotein receptor. Binding of poly( l -lysine)-asialoorosomucoid (AsOR) protein conjugates with phosphorothioate antisense oligonucleotides to chloramphenicol acetyltransferase (CAT) led to the formation of 50- to 150-nm toroids. Exposure of the antisense molecular complexes (3 µM oligonucleotide) to NIH 3T3 cells genetically modified to express both the AsOR receptor and CAT, inhibited CAT expression by 54%, which was completely blocked by excess AsOR. Equivalent inhibition of CAT activity with purified oligonucleotide alone was observed at a 30 µM concentration. Furthermore, examination of the cells using indirect immunofluorescence for the presence of CAT protein showed 28% of cells exposed to the molecular conjugates lacked any detectable CAT enzyme. Cells exposed to oligonucleotide alone showed a highly variable staining pattern, and only a few of the cells were completely void of CAT protein. Together these data demonstrate that molecular conjugates provide a highly specific and efficient system for the delivery of antisense oligonucleotides.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45543/1/11188_2005_Article_BF01232652.pd

Inconsciente e percepção na psicanálise freudiana Unconscious and perception in freudian psychoanalysis

Geralmente lembrada em sua associação com a consciência (como no Sistema Percepção- Consciência, por exemplo), a percepção encontra nas investigações de Freud vários outros destinos. Principalmente nos textos da chamada segunda tópica, mas também no artigo da Metapsicologia de 1915, "O Inconsciente", Freud nos propõe instigantes afirmações que nos aproximam de uma relação entre percepção e inconsciente. Assim, através de um percurso pelas sucessivas formulações freudianas da percepção, este artigo procura favorecer uma melhor compreensão das relações entre percepção e inconsciente.<br>Perception is usually remembered in association with consciousness (as for example in the perceptual-conscious system), but also has other destinies in Freud's investigations. Throughout Freud's succesive formulations of perception, this paper tries to offer a better understanding of the relations between perception and unconscious