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The aim of this study was to investigate any influence on olmesartan plasma pharmacokinetics from amlodipine or atenolol. We analysed pharmacokinetics and safety of olmesartan medoxomil in combination with either amlodipine or atenolol compared to respective monotherapies in two separate studies. In one study, 18 subjects received once daily treatment for 7 days with olmesartan medoxomil 20 mg alone or with amlodipine 5 mg or amlodipine 5 mg alone. In the other study, atenolol 50 mg once daily replaced amlodipine. Concentration vs. time profiles for olmesartan monotherapy were similar to combination therapy. Mean olmesartan AUCss,τ for olmesartan alone and with amlodipine were 2439 and 2388 ng h/mL and for olmesartan alone and with atenolol were 2340 and 2247 ng h/mL. Corresponding olmesartan Css,max values were 465.7 and 439.5 ng/mL for amlodipine, and 447.4 and 423.8 ng/mL for atenolol. Median tmax values for olmesartan were 1.5 h for each group in each study. Bioequivalence was established for all pharmacokinetic parameters. Lack of significant pharmacokinetic interactions between olmesartan and amlodipine or atenolol provides a basis for combination therapy. [ABSTRACT FROM AUTHOR]

Abstract We characterized visual system defects in two recessive zebrafish mutants oval and elipsa . These mutants share the syndromic phenotype of outer retinal dystrophy in conjunction with cystic renal disorder. We tested the function of the larval visual system in a behavioural assay, eliciting optokinetic eye movements by high-contrast motion stimulation while recording eye movements in parallel. Visual stimulation did not elicit eye movements in mutant larvae, while spontaneous eye movements could be observed. The retina proved to be unresponsive to light using electroretinography, indicative of a defect in the outer retina. Histological analysis of mutant retinas revealed progressive degeneration of photoreceptors, initiated in central retinal locations and spreading to more peripheral regions with increasing age. The inner retina remains unaffected by the mutation. Photoreceptors display cell type-specific immunoreactivity prior to apoptotic cell death, arguing for a dystrophic defect. Genomic mapping employing simple sequence-length polymorphisms located both mutations on different regions of zebrafish linkage group 9. These mutants may serve as accessible animal models of human outer retinal dystrophies, including oculo-renal diseases, and show the general usefulness of a behavioural genetic approach to study visual system development in the model vertebrate zebrafish. [ABSTRACT FROM AUTHOR]

Despite its central importance for understanding the molecular basis of Alzheimer's disease (AD), high-resolution structural information on amyloid β-peptide (Aβ) fibrils, which are intimately linked with AD, is scarce. We report an atomic-resolution fibril structure of the Aβ1-40 peptide with the Osaka mutation (E22Δ), associated with early-onset AD. The structure, which differs substantially from all previously proposed models, is based on a large number of unambiguous intra- and intermolecular solid-state NMR distance restraints. [ABSTRACT FROM AUTHOR]

Trotz der zentralen Bedeutung für das Verständnis der molekularen Grundlage der Alzheimer ‐ Krankheit (AK), gibt es bisher wenig Wissen über die hochaufgelösten Strukturen von Fibrillen des Amyloid ‐ β(Aβ) ‐ Peptids. Wir präsentieren hier eine atomar aufgelöste Struktur von Fibrillen des Aβ1 ‐ 40 ‐ Peptids mit der Osaka ‐ Mutation (E22Δ), die mit früh auftretender AK in Zusammenhang steht. Die Struktur, die sich grundlegend von allen bisher vorgestellten Aβ ‐ Modellen unterscheidet, basiert auf einer großen Anzahl eindeutiger intra ‐ und intermolekularer Abstandsbeschränkungen (“distance restraints”). Die Fibrillenstruktur des Aβ1 ‐ 40 ‐ Peptids mit der Osaka ‐ Mutation (E22Δ), die mit früh auftretender Alzheimer ‐ Erkrankung in Zusammenhang steht, wurde in atomarer Auflösung erhalten und unterscheidet sich grundlegend von allen bisher vorgeschlagenen Aβ ‐ Modellen: Sie ist komplex geordnet, wobei sich die Deletionsmutation in einer β ‐ Schleife der Struktur befindet. [ABSTRACT FROM AUTHOR]

Elastin‐like proteins (ELPs) are biologically important proteins and models for intrinsically disordered proteins (IDPs) and dynamic structural transitions associated with coacervates and liquid–liquid phase transitions. However, the conformational status below and above coacervation temperature and its role in the phase separation process is still elusive. Employing matrix least‐squares global Boltzmann fitting of the circular dichroism spectra of the ELPs (VPGVG)20, (VPGVG)40, and (VPGVG)60, we found that coacervation occurs sharply when a certain number of repeat units has acquired β‐turn conformation (in our sequence setting a threshold of approx. 20 repeat units). The character of the differential scattering of the coacervate suspensions indicated that this fraction of β‐turn structure is still retained after polypeptide assembly. Such conformational thresholds may also have a role in other protein assembly processes with implications for the design of protein‐based smart materials. [ABSTRACT FROM AUTHOR]

Elastin‐artige Proteine (ELPs) haben neben ihrer biologischen Funktion auch Bedeutung als Modelle für intrinsisch ungeordnete Proteine und dynamische Strukturübergänge, die mit Koazervation und Flüssig‐flüssig‐Phasenübergängen einhergehen. Über den Konformerenzustand direkt unter‐ und oberhalb der Koazervationstemperatur und dessen Rolle im Phasentrennprozess ist allerdings nach wie vor wenig bekannt. Durch globales Matrix‐kleinste‐Quadrate‐Boltzmann‐Fitting der Zirkulardichroismus‐Spektren dreier ELPs deckten wir auf, dass es unmittelbar zur Koazervation kommt, wenn eine bestimmte Anzahl von Wiederholungseinheiten β‐Turn‐Konformation angenommen hat (hier etwa 20 Wiederholungseinheiten). Der Charakter der differenziellen Streuung der Koazervat‐Suspensionen wies darauf hin, dass dieser Anteil an β‐Turn‐Struktur auch nach der Zusammenlagerung der Polypeptide erhalten bleibt. Möglicherweise spielen derartige "Konformationsschwellenwerte" auch in anderen Protein‐Zusammenlagerungsprozessen eine Rolle. [ABSTRACT FROM AUTHOR]