Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 2 de 2
Filter
Add more filters










Database
Language
Publication year range
1.
Science ; 310(5745): 96-100, 2005 Oct 07.
Article in English | MEDLINE | ID: mdl-16210536

ABSTRACT

Most people hold beliefs about personality characteristics typical of members of their own and others' cultures. These perceptions of national character may be generalizations from personal experience, stereotypes with a "kernel of truth," or inaccurate stereotypes. We obtained national character ratings of 3989 people from 49 cultures and compared them with the average personality scores of culture members assessed by observer ratings and self-reports. National character ratings were reliable but did not converge with assessed traits. Perceptions of national character thus appear to be unfounded stereotypes that may serve the function of maintaining a national identity.


Subject(s)
Character , Culture , Ethnicity , Personality , Adolescent , Adult , Cross-Cultural Comparison , Female , Humans , Male , Personality Assessment , Reproducibility of Results , Social Perception , Stereotyping , Surveys and Questionnaires
2.
Gene Ther ; 6(11): 1798-807, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10602375

ABSTRACT

Association of a targeting ligand such as transferrin, or an endosome disrupting peptide such as GALA, with cationic liposome-DNA complexes ('lipoplexes') results in a significant enhancement of transfection of several cell types (Simões S et al, Gene Therapy 1998; 5: 955-964). Although these strategies can overcome some of the barriers to gene delivery by lipoplexes, the mechanisms by which they actually enhance tranfection is not known. In studies designed to establish the targeting specificity of transferrin, we found that apo-transferrin enhances transfection to the same extent as transferrin, indicating that internalization of the lipoplexes is mostly independent of transferrin receptors. These observations were reinforced by results obtained from competitive inhibition studies either by preincubating the cells with an excess of free ligand or with various 'receptor-blocking' lipoplexes. Transfection of cells in the presence of drugs that interfere with the endocytotic pathway provided additional insights into the mechanisms of gene delivery by transferrin- or GALA-lipoplexes. Our results indicate that transferrin-lipoplexes deliver transgenes by endocytosis primarily via a non-receptor-mediated mechanism, and that acidification of the endosomes is partially involved in this process.


Subject(s)
DNA/metabolism , Gene Transfer Techniques , Liposomes/metabolism , Peptides/metabolism , Transferrin/metabolism , Cell Survival , DNA/chemistry , Endocytosis , HeLa Cells , Humans , Hydrogen-Ion Concentration , Liposomes/chemistry , Peptides/chemistry , Receptors, Transferrin/physiology , Transfection/physiology , Transferrin/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL
...