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1.
Psychol Rep ; 116(3): 685-703, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25933042

RESUMO

For the purpose of retrospective assessment and characterization of childhood trauma in adults, the factorial validity of the short form of the Childhood Trauma Questionnaire (CTQ-SF) in Germany was evaluated by conducting confirmatory factor analyses for three samples including 1,524 adult psychiatric patients, 224 inmates, and 295 university students. In addition, sex-specific confirmatory factor analyses were performed within each sample. Because several authors have suggested a different factor structure than that originally proposed in the manual, two competing models focusing on the Physical neglect subscale were examined. In psychiatric patients and inmates, the fit indices were reasonable to good. Among the students, factor loadings were markedly lower, and fit indices were poor. Sex-specific analyses did not indicate sex differences. Comparing the original and the alternative models revealed better fit indices of the original factor structure. The present findings indicate that the German version of the CTQ-SF has factorial validity in psychiatric patients and inmates, but not in students.


Assuntos
Acontecimentos que Mudam a Vida , Transtornos Mentais/psicologia , Prisioneiros/psicologia , Estudantes/psicologia , Inquéritos e Questionários/normas , Adulto , Criança , Análise Fatorial , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Universidades , Adulto Jovem
2.
Chembiochem ; 10(15): 2504-12, 2009 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-19739189

RESUMO

Efficient drug delivery is essential for many therapeutic applications. In this context, Trojan peptoids have attracted attention as powerful tools to deliver bioactive molecules into living cells. Certain cell-penetrating peptides, peptide mimetics, and peptoids have been shown to be endowed with a transport function and the structural features of this function have been characterized. However, most of the research has been done by using mammalian cell cultures as model organisms and the actual cellular mechanism of membrane passage has not been elucidated. Plant cells, which are encased in a cellulosic cell wall and differ in membrane composition, represent an alternative experimental system to address this issue, but so far, have attracted only little attention for both peptide- and peptoid-based carrier systems. Moreover, efficient delivery of nonproteinaceous bioactive macromolecules into living plant cells could complement genetic engineering in biotechnological applications, such as metabolic engineering and molecular farming. In the present study, we investigated carrier peptoids with or without guanidinium side chains with regard to their uptake into plant cells, the cellular mechanism of uptake, and intracellular localization. We can show that in contrast to polyamine peptoids (polylysine-like) fluorescently labeled polyguanidine peptoids (polyarginine-like) enter rapidly into tobacco BY-2 cells without affecting the viability of these cells. A quantitative comparison of this uptake with endocytosis of fluorescently labeled dextranes indicates that the main uptake of the guanidinium peptoids occurs between 30-60 min after the start of incubation and clearly precedes endocytosis. Dual visualization with the endosomal marker FM4-64 shows that the intracellular guanidinium peptoid is distinct from endocytotic vesicles. Once the polyguanidine peptoids have entered the cell, they associate with actin filaments and microtubules. By pharmacological manipulation of the cytoskeleton we tested whether the association with the cytoskeleton is necessary for uptake, and observed that the actin inhibitor latrunculin B as well as the microtubule inhibitor oryzalin impaired uptake and intracellular spread of the guanidinium carrier to a certain extent. These findings are discussed with respect to the potential mechanisms of uptake and with respect to the potential of Trojan peptoids as tools for metabolic engineering in plant biotechnology.


Assuntos
Portadores de Fármacos/metabolismo , Nicotiana/citologia , Peptoides/metabolismo , Linhagem Celular , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Endossomos/metabolismo , Peptoides/síntese química , Peptoides/química
3.
J Med Chem ; 51(3): 376-9, 2008 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-18215012

RESUMO

Efficient drug delivery is essential for many therapeutic applications. Some cell-penetrating peptides, peptide mimetics, and peptoids express transport function that, however, lack in most cases specific intracellular destination. In this study, carrier-peptoids with either amino or guanidinium side chains, were investigated with regard to their cellular uptake, toxicity, and intracellular localization. Transport specifically to the cytosol or to the nuclei was observed, thus providing a powerful tool for targeted drug delivery.


Assuntos
Aminas/síntese química , Núcleo Celular/metabolismo , Citosol/metabolismo , Portadores de Fármacos/síntese química , Guanidinas/síntese química , Peptoides/síntese química , Aminas/química , Aminas/farmacocinética , Linhagem Celular , Sobrevivência Celular , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Guanidinas/química , Guanidinas/farmacocinética , Humanos , Peptoides/química , Peptoides/farmacocinética
4.
Org Biomol Chem ; 5(17): 2767-9, 2007 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-17700843

RESUMO

A new staining reagent was prepared and its ability to stain several azide-containing agents on TLC plates was determined.


Assuntos
Azidas/química , Corantes/química , Azidas/síntese química , Cromatografia em Camada Fina , Corantes/síntese química , Estrutura Molecular
5.
Bioconjug Chem ; 18(2): 342-54, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17326607

RESUMO

For many therapeutic applications, it has become more and more important to find synthetic compounds that have the ability to transport a variety of drugs and cargo molecules into cells and tissues. Like arginine-rich cell-penetrating peptides (CPPs), it is already known that peptide mimetics such as beta-peptides and peptoids can also express a transport function. In this study, ten fluorophore-labeled chiral and achiral peptoids with different backbone lengths and side chains as well as three peptoids coupled to a therapeutically active porphyrin moiety were prepared using a highly modular solid-phase synthesis (SPP) approach. To compare the structural determinants with the cellular uptake efficiency, all peptoids were analyzed by live cell imaging. All cells show an even vesicular distribution of the internalized peptoids, also revealing that a vesicular escape into the cytosol was stronger for peptoids with longer backbones. Moreover, the uptake efficiency correlated with both the incubation time and the given concentration. Toxicology tests and uptake experiments with porphyrin-coupled peptoids indicate their suitability for application as robust and readily available drug delivery systems or intracellular probes.


Assuntos
Arginina/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Oligopeptídeos/síntese química , Peptoides/síntese química , Animais , Arginina/farmacocinética , Células COS/efeitos dos fármacos , Permeabilidade da Membrana Celular , Células Cultivadas/efeitos dos fármacos , Chlorocebus aethiops , Meios de Cultura Livres de Soro/farmacologia , Portadores de Fármacos/farmacocinética , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Oligopeptídeos/química , Oligopeptídeos/farmacocinética , Peptoides/química , Peptoides/farmacocinética , Conformação Proteica
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