A5058700363- Connexins and lens biology
- Heat shock proteins research
- Advanced X-ray Imaging Techniques
- Optical measurement and interference techniques
- Biochemical effects in animals
- Ocular Surface and Contact Lens
- Enzyme Structure and Function
- Corneal surgery and disorders
- Ophthalmology and Visual Impairment Studies
- Corneal Surgery and Treatments
- Spectroscopy Techniques in Biomedical and Chemical Research
- Yersinia bacterium, plague, ectoparasites research
- Bee Products Chemical Analysis
- Photoreceptor and optogenetics research
- Digital Holography and Microscopy
- Electrochemical sensors and biosensors
- Veterinary Equine Medical Research
- Lipid Membrane Structure and Behavior
- Ergonomics and Musculoskeletal Disorders
- Proteoglycans and glycosaminoglycans research
- Collagen: Extraction and Characterization
- Neurobiology and Insect Physiology Research
- Advanced Glycation End Products research
- Chemical Thermodynamics and Molecular Structure
- Advanced Electron Microscopy Techniques and Applications
Cardiff University
2010-2024
// Barbara Pierscionek 1 , Mehdi Bahrami Masato Hoshino 2 Kentaro Uesugi Justyn Regini 3 and Naoto Yagi Faculty of Science, Engineering Computing, Kingston University London, Kingston-upon-Thames, United Kingdom Japan Synchrotron Radiation Research Institute (SPring-8), Sayo, Hyogo, School Vision Sciences, Cardiff University, Cardiff, Correspondence to: Pierscionek, email: Keywords : ageing, eye lens, refractive index gradients, growth, size, Gerotarget Received June 20, 2015 Accepted August...
The lens, a major optical component of the eye, has gradient refractive index, which is required to provide sufficient power and image quality. index variations across lens are dependent on distributions concentrations varying protein classes. In this study, we present first measurements in situ eye from five species using specially constructed X-ray Talbot grating interferometer. have been conducted two planes: one containing optic axis (the sagittal plane) plane orthogonal equatorial...
The structural basis of zones discontinuity in the living human eye lens has not been elucidated, and there is no conclusive explanation for what relevance they may have to structure function lens. Newly developed synchrotron radiation based X-ray Talbot interferometry enabled detection subtle fluctuations which, when used mathematical modelling simulate reflected scattered light, can recreate image seen eye. results this study show that be caused by refractive index gradient as well from...
De-epithelialised and de-endothelialised bovine corneal stromas with a hydration of 3.2 equilibrated at 154 mM NaCl buffered pH 7.4 had their optical density (400-750 nm) measured. Stromas against 10, 20, 30, 50 or 100 made isotonic to by supplementing sorbitol were progressively more transparent as increased. Hypertonic equilibration 300, 600 1000 resulted in progressive loss transparency compared NaCl. Light scattering function wavelength fitted lambda(-3) well for 50, preparations between...
Chondroitin sulfate (CS) is an important component of the extracellular matrix in multiple biological tissues. In cornea, CS glycosaminoglycan (GAG) exists hybrid form, whereby some repeating disaccharides are dermatan (DS). These CS/DS GAGs through their presence on proteoglycans, decorin and biglycan, help control collagen fibrillogenesis organization. also acts as a regulatory ligand for spectrum signaling molecules, including morphogens, cytokines, chemokines, enzymes during corneal...
A major structure/function relationship in the eye lens is that between constituent proteins, crystallins and optical property of refractive index. Structural breakdown leads to cataract has been investigated a number studies; concomitant changes optics, namely increases light attenuation have also well documented. Specific index gradient cause such attenuation, however, are not studied because previous methods measuring require transparent samples. The X-ray Talbot interferometric method...
Recent studies apparently finding deleterious effects of radiation exposure on cataract formation in birds and voles living near Chernobyl represent a major challenge to current protection regulations. This study conducted an integrated assessment cataractogenesis using the most advanced technologies available assess status lenses extracted from fish caught at both Ukraine Fukushima Japan. It was hypothesised that these novel data would reveal positive correlations between dose early...
Alpha-crystallin, a ubiquitous molecular chaperone, is found in high concentrations the lens. Its structure and precise mechanism of action, however, are unknown. The purpose these experiments was to further understanding chaperone function alpha-crystallin.X-ray- neutron-solution-scattering studies were used measure radius gyration bovine lens alpha-crystallin when complexed with its target protein beta-crystallin both normal heavy-water-based solutions. Spectrophotometry as assay.The on...
The development of the eye requires co-ordinated integration optical and neural elements to create a system with requisite optics for given animal. lens has lamellar structure gradually varying protein concentrations that increase towards centre, creating gradient refractive index or GRIN. This provides enhanced image quality compared homogeneous lens. GRIN during ocular embryogenesis not been investigated previously. study presents measurements using synchrotron X-ray Talbot interferometry...
Purpose: The purpose of this study is to compare the structural integrity bovine lenses using small-angle X-ray diffraction techniques, before and after freezing, both liquid nitrogen a −20°C freezer understand molecular changes that occur see if any permanent result from freezing thawing process. Materials Methods: We used scattering investigate effects whole eye (i) in (ii) at −20°C, better basis phase transitions. Results: Lenses frozen thawed more rapidly than those placed −20°C. With...
ABSTRACT The cephalopod eye lens is unique because it has evolved as a compound structure with two physiologically distinct segments. However, the detailed ultrastructure of this and precise optical role each segment are far from clear. To help elucidate structure–function relationships in lens, we conducted multiple structural investigations on squid. Synchrotron x-ray scattering transmission electron microscopy disclose that an extensive network features resemble cell membrane complexes...
The small heat shock protein (sHSP) I±-crystallin occurs in nearly all the major tissues of body. It has two main functions; helping maintain transparency eye lens and as a molecular chaperone. We have investigated gels over temperature range from 20 to 70oC using wide low angle X-ray scattering techniques. data show moderate increase both spacing intensity the reflection 45oC. This was followed by dramatic 45 70oC. Upon cooling, this effect found be irreversible an eleven-hour period....
Summary Zones of discontinuity seen in living healthy human lenses when they are viewed using biomicroscopy not understood from structural or functional perspectives. They scatter light but do impede impair vision and there no known structures that could explain their presence. Previous methods measured changes the optical property refractive index across tissue create gradient structure did detect any variations be related to zones discontinuity. Recent work undertaken at SPring‐8...
Purpose During the accommodation process, morphology of lens changes. The crystallin proteins within fibres are primary structural unit organisation at cellular level, and play a major role in maintaining transparency refractive power. All information about from X-ray scattering techniques have so far been performed on samples relaxed accommodated state. It is thought that largest changes occur nucleus during accommodation. Aims To measure any average distance between proteins, their...