RESUMEN
DNA encoded ligands are self-assembled into bivalent complexes and chemically ligated to link their identities. To demonstrate their potential as a combinatorial screening platform for avidity interactions, the optimal bivalent aptamer design (examplar ligands) for human alpha-thrombin is determined in a single round of selection and the DNA scaffold replaced with minimal impact on the final design.
Asunto(s)
Técnicas Químicas Combinatorias , ADN/química , Bibliotecas de Moléculas Pequeñas/química , Trombina/análisis , Cristalografía por Rayos X , Humanos , Ligandos , Modelos Moleculares , Estructura MolecularAsunto(s)
Países en Desarrollo , Discapacidades del Desarrollo/enfermería , Empleo/psicología , Adolescente , Niño , Preescolar , Coerción , Comparación Transcultural , Discapacidades del Desarrollo/etiología , Discapacidades del Desarrollo/prevención & control , Discapacidades del Desarrollo/psicología , Femenino , Alemania , Trata de Personas/psicología , Humanos , Masculino , Factores de RiesgoAsunto(s)
Características de la Residencia , Clase Social , Medio Social , Factores Socioeconómicos , Niño , Preescolar , Femenino , Alemania , Conductas Relacionadas con la Salud , Humanos , Lactante , Recién Nacido , Estilo de Vida , Sobrepeso/enfermería , Sobrepeso/psicología , Embarazo , Carencia Psicosocial , Factores de RiesgoRESUMEN
Aptamer microarrays are a promising high-throughput method for ultrasensitive detection of multiple analytes, but although much is known about the optimal synthesis of oligonucleotide microarrays used in hybridization-based genomics applications, the bioaffinity interactions between aptamers and their targets is qualitatively different and requires significant changes to synthesis parameters. Focusing on streptavidin-binding DNA aptamers, we employed light-directed in situ synthesis of microarrays to analyze the effects of sequence fidelity, linker length, surface probe density, and substrate functionalization on detection sensitivity. Direct comparison with oligonucleotide hybridization experiments indicates that aptamer microarrays are significantly more sensitive to sequence fidelity and substrate functionalization and have different optimal linker length and surface probe density requirements. Whereas microarray hybridization probes generate maximum signal with multiple deletions, aptamer sequences with the same deletion rate result in a 3-fold binding signal reduction compared with the same sequences synthesized for maximized sequence fidelity. The highest hybridization signal was obtained with dT 5mer linkers, and the highest aptamer signal was obtained with dT 11mers, with shorter aptamer linkers significantly reducing the binding signal. The probe hybridization signal was found to be more sensitive to molecular crowding, whereas the aptamer probe signal does not appear to be constrained within the density of functional surface groups commonly used to synthesize microarrays.
Asunto(s)
Aptámeros de Nucleótidos/biosíntesis , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Estimulación Luminosa/métodos , Aptámeros de Nucleótidos/genética , Unión Proteica/fisiologíaAsunto(s)
Antibacterianos/uso terapéutico , Mortalidad del Niño/tendencias , Control de Enfermedades Transmisibles/tendencias , Países en Desarrollo , Mortalidad Infantil/tendencias , Vacunación/tendencias , Adolescente , Causas de Muerte/tendencias , Niño , Preescolar , Comparación Transcultural , Predicción , Humanos , LactanteAsunto(s)
Anomalías Congénitas/enfermería , Exposición Profesional/efectos adversos , Exposición Paterna/efectos adversos , Efectos Tardíos de la Exposición Prenatal/enfermería , Anomalías Congénitas/etiología , Anomalías Congénitas/prevención & control , Femenino , Alemania , Humanos , Recién Nacido , Masculino , Exposición Profesional/prevención & control , Exposición Paterna/prevención & control , Embarazo , Efectos Tardíos de la Exposición Prenatal/prevención & controlAsunto(s)
Maltrato a los Niños/prevención & control , Violencia Doméstica/prevención & control , Niño , Maltrato a los Niños/estadística & datos numéricos , Estudios Transversales , Niños con Discapacidad , Violencia Doméstica/estadística & datos numéricos , Educación , Alemania , Humanos , Factores de RiesgoAsunto(s)
Trastornos del Espectro Alcohólico Fetal/enfermería , Diagnóstico de Enfermería , Niño , Preescolar , Diagnóstico Precoz , Femenino , Trastornos del Espectro Alcohólico Fetal/diagnóstico , Trastornos del Espectro Alcohólico Fetal/prevención & control , Alemania , Humanos , Lactante , Recién Nacido , Masculino , Enfermería Maternoinfantil , Embarazo , Atención Prenatal , Factores de RiesgoRESUMEN
L-DNA is the perfect mirror-image form of the naturally occurring d-conformation of DNA. Therefore, L-DNA duplexes have the same physical characteristics in terms of solubility, duplex stability and selectivity as D-DNA but form a left-helical double-helix. Because of its chiral difference, L-DNA does not bind to its naturally occurring D-DNA counterpart, however. We analysed some of the properties that are typical for L-DNA. For all the differences, L-DNA is chemically compatible with the D-form of DNA, so that chimeric molecules can be synthesized. We take advantage of the characteristics of L-DNA toward the establishment of a universal microarray that permits the analysis of different kinds of molecular diagnostic information in a single experiment on a single platform, in various combinations. Typical results for the measurement of transcript level variations, genotypic differences and DNA-protein interactions are presented. However, on the basis of the characteristic features of L-DNA, also other applications of this molecule type are discussed.
Asunto(s)
ADN/química , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Animales , ADN/síntesis química , ADN/metabolismo , Proteínas de Unión al ADN/análisis , ADN Polimerasa Dirigida por ADN/metabolismo , Desoxirribonucleasas/metabolismo , Perfilación de la Expresión Génica/métodos , Marcadores Genéticos , Técnicas de Diagnóstico Molecular , Conformación de Ácido Nucleico , Sondas de Oligonucleótidos , Polimorfismo de Nucleótido Simple , EstereoisomerismoAsunto(s)
Procedimientos de Cirugía Plástica/psicología , Procedimientos de Cirugía Plástica/tendencias , Psicología del Adolescente , Psicología Infantil , Adolescente , Adulto , Niño , Unión Europea , Femenino , Alemania , Humanos , Lipectomía , Masculino , Mamoplastia , Relaciones Padres-Hijo , Procedimientos de Cirugía Plástica/estadística & datos numéricos , Religión y Medicina , Rinoplastia , Estados UnidosRESUMEN
A general synthetic approach to various isoxanthopterin-nucleosides starting from 6-methyl-2-methylthio-4(3H),7(8H)-pterdinedione (1) has been developed. Ribosylation with 1-O-acetyl-2,3,5-tri-O-benzoyl-beta-D-ribofuranose via the silyl-method led to 2 and reaction with 1-chloro-2-deoxy-3,5-di-O-p-toluoyl-alpha-D-ribofuranose using the DBU-method afforded 28. Protection of the amide function at O4 by benzylation to 5 and by a Mitsunobu reaction with 2-(4-nitrophenyl)ethanol to 29 gave soluble intermediates which can be oxidized to the corresponding 2-methylsulfonyl derivatives 8 and 30, respectively. Nucleophilic displacement reactions of the highly reactive 2-methylsulfonyl functions by various amines proceeded under mild conditions to isoxanthopterin-N8-ribo- (11-17) and 2'-deoxyribomucleosides (31-33). Debenzylation can be achieve by Pd-catalyzed hydrogenation (9 to 19) and cleavage of the npe-protecting group (31, 32 to 34, 35) works well with DBU by beta-elimination.