Search results for "Mimetic"
showing 10 items of 218 documents
Distigmine bromide induced acute psychotic disorder in a patient with multiple sclerosis.
2003
AbstractA female patient with multiple sclerosis (MS) suffered from an acute psychotic disorder after taking distigmine bromide for detrusor dysfunction. She showed a dramatic relief of her symptoms after the medication, distigmine bromide, was stopped. Distigmine is not supposed to penetrate the blood-brain barrier (BBB). However, in MS patients a leakage of the BBB could be hypothesized.
Some pharmacological properties of the false cholinergic transmitter acetylpyrrolidinecholine and its precursor pyrrolidinecholine
1976
The acetylchline analogue acetylpyrrolidinecholine as well as the choline analogue pyrrolidinecholine were synthesized and the cholinergic properties of both substances were investigated on the guinea-pig ileum, rat blood pressure and frog rectus abdominis muscle. Acetylpyrrolidinecholine was 3-5 times less potent than acetylcholine on the three preparations tested. The dose-response curves to acetylpyrrolidinecholine were shifted to the right in a parallel manner by atropine and (+)-tubocurarine. The dissociation constants for atropine and (+)-tubocurarine obtained with acetylpyrrolidinecholine as agonist were not different from those obtained with acetylcholine. This indicates that acetyl…
EFFECTS OF VANADATE ON RESPONSES OF GUINEA-PIG ISOLATED TRACHEA TO SPASMOGENS
1993
Abstract The effects of vanadate on the contractility of the guinea-pig isolated trachea was examined. Vanadate (0·1 Mm) produced a sustained contraction that was abolished in Ca2+-free EGTA (0·1 Mm)-containing physiological salt solution but was resistant to verapamil (1 μm). Vanadate (0·1 Mm) depressed tracheal responses to CaCl2 (in Ca2+-free depolarizing solution), KCl, acetylcholine, histamine and 5-hydroxytryptamine. For vanadate (10 μm), the inhibition of spasmogenic responses only reached statistical significance for histamine and 5-hydroxytryptamine. Caffeine (1 Mm)-induced spasm (trachea at 20°C in the presence of indomethacin (2·8 μm)) was not affected by vanadate (10 μm-0·1 Mm).…
Bioinspired synthesis of multifunctional inorganic and bio-organic hybrid materials
2012
Owing to their physical and chemical properties, inorganic functional materials have tremendous impacts on key technologies such as energy generation and storage, information, medicine, and automotive engineering. Nature, on the other hand, provides evolution-optimized processes, which lead to multifunctional inorganic–bio-organic materials with complex structures. Their formation occurs under physiological conditions, and is goverened by a combination of highly regulated biological processes and intrinsic chemical properties. Nevertheless, insights into the molecular mechanisms of biomineralization open up promising perspectives for bioinspired and biomimetic design and the development of …
Iris-Like Tunable Aperture Employing Liquid-Crystal Elastomers
2014
A liquid-crystal elastomer (LCE) iris inspired by the human eye is demonstrated. With integrated polyimide-based platinum heaters, the LCE material is thermally actuated. The radial contraction direction, similar to a mammalian iris, is imprinted to the LCE by a custom-designed magnetic field. Actuation of the device is reproducible over multiple cycles and controllable at intermediate contraction states.
Biomineral Amorphous Lasers through Light-Scattering Surfaces Assembled by Electrospun Fiber Templates
2018
New materials aim at exploiting the great control of living organisms over molecular architectures and minerals. Optical biomimetics has been widely developed by microengineering, leading to photonic components with order resembling those found in plants and animals. These systems, however, are realized by complicated and adverse processes. Here we show how biomineralization might enable the one-step generation of components for amorphous photonics, in which light is made to travel through disordered scattering systems, and particularly of active devices such as random lasers, by using electrospun fiber templates. The amount of bio-enzymatically produced silica is related to light-scatterin…
Elastomeric Electrospun Polyurethane Scaffolds: The Interrelationship Between Fabrication Conditions, Fiber Topology, and Mechanical Properties
2010
Electrospinning has been gaining increasing popularity in the fabrication of engineered tissue scaffolds due to its ability to produce nano to micro scale fibrous sheets. Many investigators have attempted to apply various degrees of control to this process in order to produce fiber meshes with more predictable patterns. These attempts have largely been limited to controlling fiber alignment and have fallen into two categories: physical manipulation of the fibers by pulling them into alignment using a rapidly spinning mandrel[1–3] or manipulation of the electric field during fabrication.[4, 5]
Paper-reinforced biomimetic cellular structures for automotive applications
2009
The aim of this work was to make and test some sandwich structures, made of biomimetic cellular cores of recycled paper. In a preliminary study some paper laminates were investigated. Then two different kinds of cores were made by simple processes, according to two natural structures (i.e. feather and honeycomb). To evaluate the mechanical properties of these new sandwiches, static flexural, flatwise and edgewise compression tests were performed.
Surface Functionalization of Metal–Organic Framework Crystals with Catechol Coatings for Enhanced Moisture Tolerance
2021
Robust catechol coatings for enhanced moisture tolerance were produced in one step by direct reaction of Hong Kong University of Science and Technology (HKUST) with synthetic catechols. We ascribe the rapid formation of homogeneous coatings around the metal–organic framework particles to the biomimetic catalytic activity of Cu(II) dimers in the external surface of the crystals. Use of fluorinated catechols results in hydrophobic, permeable coatings that protect HKUST from water degradation while retaining close to 100% of its original sorption capacity.
Applications of diatoms and silica nanotechnology in biosensing, drug and gene delivery, and formation of complex metal nanostructures
2011
Abstract Diatoms, single-cell eukaryotic microalgae, are present in nearly every water habitat and their silicon-dioxide (silica)-based cell walls of tens to hundreds of micrometers in size are the most interesting feature to be used in nanotechnology, including biosensing, drug delivery, molecular separation, molecular biology, biomimetics, frustule formation, and electronic, photonic, optical and structural materials. In this review, we present recent progress in applications of diatoms and silica nanomaterials in biosensing, drug and gene delivery, and formation of complex metal nanostructures.