Pieces of glass or other transparent materials used for magnification or increased visual acuity.
Lenses designed to be worn on the front surface of the eyeball. (UMDNS, 1999)
Soft, supple contact lenses made of plastic polymers which interact readily with water molecules. Many types are available, including continuous and extended-wear versions, which are gas-permeable and easily sterilized.
Artificial implanted lenses.
The portion of the crystalline lens surrounding the nucleus and bound anteriorly by the epithelium and posteriorly by the capsule. It contains lens fibers and amorphous, intercellular substance.
The thin noncellular outer covering of the CRYSTALLINE LENS composed mainly of COLLAGEN TYPE IV and GLYCOSAMINOGLYCANS. It is secreted by the embryonic anterior and posterior epithelium. The embryonic posterior epithelium later disappears.
The core of the crystalline lens, surrounded by the cortex.
Partial or complete opacity on or in the lens or capsule of one or both eyes, impairing vision or causing blindness. The many kinds of cataract are classified by their morphology (size, shape, location) or etiology (cause and time of occurrence). (Dorland, 27th ed)
A heterogeneous family of water-soluble structural proteins found in cells of the vertebrate lens. The presence of these proteins accounts for the transparency of the lens. The family is composed of four major groups, alpha, beta, gamma, and delta, and several minor groups, which are classed on the basis of size, charge, immunological properties, and vertebrate source. Alpha, beta, and delta crystallins occur in avian and reptilian lenses, while alpha, beta, and gamma crystallins occur in all other lenses.
Hydrophilic contact lenses worn for an extended period or permanently.
Incomplete rupture of the zonule with the displaced lens remaining behind the pupil. In dislocation, or complete rupture, the lens is displaced forward into the anterior chamber or backward into the vitreous body. When congenital, this condition is known as ECTOPIA LENTIS.
Sterile solutions used to clean and disinfect contact lenses.
Insertion of an artificial lens to replace the natural CRYSTALLINE LENS after CATARACT EXTRACTION or to supplement the natural lens which is left in place.
The normal decreasing elasticity of the crystalline lens that leads to loss of accommodation.
The dioptric adjustment of the EYE (to attain maximal sharpness of retinal imagery for an object of regard) referring to the ability, to the mechanism, or to the process. Ocular accommodation is the effecting of refractive changes by changes in the shape of the CRYSTALLINE LENS. Loosely, it refers to ocular adjustments for VISION, OCULAR at various distances. (Cline et al., Dictionary of Visual Science, 4th ed)
Refraction of LIGHT effected by the media of the EYE.
The posterior aspect of the casing that surrounds the natural CRYSTALLINE LENS.
A class of crystallins that provides refractive power and translucency to the lens (LENS, CRYSTALLINE) in VERTEBRATES. Beta-crystallins are similar in structure to GAMMA-CRYSTALLINS in that they both contain Greek key motifs. Beta-crystallins exist as oligomers formed from acidic (BETA-CRYSTALLIN A CHAIN) and basic (BETA-CRYSTALLIN B CHAIN) subunits.
The removal of a cataractous CRYSTALLINE LENS from the eye.
Absence of crystalline lens totally or partially from field of vision, from any cause except after cataract extraction. Aphakia is mainly congenital or as result of LENS DISLOCATION AND SUBLUXATION.
A pair of ophthalmic lenses in a frame or mounting which is supported by the nose and ears. The purpose is to aid or improve vision. It does not include goggles or nonprescription sun glasses for which EYE PROTECTIVE DEVICES is available.
A subclass of crystallins that provides the majority of refractive power and translucency to the lens (LENS, CRYSTALLINE) in VERTEBRATES. Alpha-crystallins also act as molecular chaperones that bind to denatured proteins, keep them in solution and thereby maintain the translucency of the lens. The proteins exist as large oligomers that are formed from ALPHA-CRYSTALLIN A CHAIN and ALPHA-CRYSTALLIN B CHAIN subunits.
The organ of sight constituting a pair of globular organs made up of a three-layered roughly spherical structure specialized for receiving and responding to light.
A plant genus of the FABACEAE family known for the seeds used as food.
The transparent anterior portion of the fibrous coat of the eye consisting of five layers: stratified squamous CORNEAL EPITHELIUM; BOWMAN MEMBRANE; CORNEAL STROMA; DESCEMET MEMBRANE; and mesenchymal CORNEAL ENDOTHELIUM. It serves as the first refracting medium of the eye. It is structurally continuous with the SCLERA, avascular, receiving its nourishment by permeation through spaces between the lamellae, and is innervated by the ophthalmic division of the TRIGEMINAL NERVE via the ciliary nerves and those of the surrounding conjunctiva which together form plexuses. (Cline et al., Dictionary of Visual Science, 4th ed)
The anterior aspect of the casing that surrounds the natural CRYSTALLINE LENS.
A refractive error in which rays of light entering the EYE parallel to the optic axis are brought to a focus in front of the RETINA when accommodation (ACCOMMODATION, OCULAR) is relaxed. This results from an overly curved CORNEA or from the eyeball being too long from front to back. It is also called nearsightedness.
A broad family of synthetic organosiloxane polymers containing a repeating silicon-oxygen backbone with organic side groups attached via carbon-silicon bonds. Depending on their structure, they are classified as liquids, gels, and elastomers. (From Merck Index, 12th ed)
A procedure for removal of the crystalline lens in cataract surgery in which an anterior capsulectomy is performed by means of a needle inserted through a small incision at the temporal limbus, allowing the lens contents to fall through the dilated pupil into the anterior chamber where they are broken up by the use of ultrasound and aspirated out of the eye through the incision. (Cline, et al., Dictionary of Visual Science, 4th ed & In Focus 1993;1(1):1)
A subclass of crystallins found in the lens (LENS, CRYSTALLINE) in BIRDS and REPTILES. They are inactive forms of the enzyme argininosuccinate lyase.
Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.
A refractive error in which rays of light entering the eye parallel to the optic axis are brought to a focus behind the retina, as a result of the eyeball being too short from front to back. It is also called farsightedness because the near point is more distant than it is in emmetropia with an equal amplitude of accommodation. (Dorland, 27th ed)
Deviations from the average or standard indices of refraction of the eye through its dioptric or refractive apparatus.
A specialized field of physics and engineering involved in studying the behavior and properties of light and the technology of analyzing, generating, transmitting, and manipulating ELECTROMAGNETIC RADIATION in the visible, infrared, and ultraviolet range.
Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.
Lenses, generally made of plastic or silicone, that are implanted into the eye in front of the natural EYE LENS, by the IRIS, to improve VISION, OCULAR. These intraocular lenses are used to supplement the natural lens instead of replacing it.
Presence of an intraocular lens after cataract extraction.
A class of porins that allow the passage of WATER and other small molecules across CELL MEMBRANES.
The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.
Absence of the crystalline lens resulting from cataract extraction.
The basic subunit of beta-crystallins.
Polymers of silicone that are formed by crosslinking and treatment with amorphous silica to increase strength. They have properties similar to vulcanized natural rubber, in that they stretch under tension, retract rapidly, and fully recover to their original dimensions upon release. They are used in the encapsulation of surgical membranes and implants.
The most anterior portion of the uveal layer, separating the anterior chamber from the posterior. It consists of two layers - the stroma and the pigmented epithelium. Color of the iris depends on the amount of melanin in the stroma on reflection from the pigmented epithelium.
The making of a continuous circular tear in the anterior capsule during cataract surgery in order to allow expression or phacoemulsification of the nucleus of the lens. (Dorland, 28th ed)
Inflammation of the cornea.
The fitting and adjusting of artificial parts of the body. (From Stedman's, 26th ed)
An excessive amount of fluid in the cornea due to damage of the epithelium or endothelium causing decreased visual acuity.
One or more layers of EPITHELIAL CELLS, supported by the basal lamina, which covers the inner or outer surfaces of the body.
Maf proto-oncogene protein is the major cellular homolog of the V-MAF ONCOGENE PROTEIN. It was the first of the mammalian MAF TRANSCRIPTION FACTORS identified, and it is induced in activated T-LYMPHOCYTES and regulates GENETIC TRANSCRIPTION of INTERLEUKIN-4. c-maf is frequently translocated to an immunoglobulin locus in MULTIPLE MYELOMA.
A family of transcription factors that control EMBRYONIC DEVELOPMENT within a variety of cell lineages. They are characterized by a highly conserved paired DNA-binding domain that was first identified in DROSOPHILA segmentation genes.
The front third of the eyeball that includes the structures between the front surface of the cornea and the front of the VITREOUS BODY.
The fluid secreted by the lacrimal glands. This fluid moistens the CONJUNCTIVA and CORNEA.
The measurement of curvature and shape of the anterior surface of the cornea using techniques such as keratometry, keratoscopy, photokeratoscopy, profile photography, computer-assisted image processing and videokeratography. This measurement is often applied in the fitting of contact lenses and in diagnosing corneal diseases or corneal changes including keratoconus, which occur after keratotomy and keratoplasty.
Unequal curvature of the refractive surfaces of the eye. Thus a point source of light cannot be brought to a point focus on the retina but is spread over a more or less diffuse area. This results from the radius of curvature in one plane being longer or shorter than the radius at right angles to it. (Dorland, 27th ed)
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
The transparent, semigelatinous substance that fills the cavity behind the CRYSTALLINE LENS of the EYE and in front of the RETINA. It is contained in a thin hyaloid membrane and forms about four fifths of the optic globe.
One of the alpha crystallin subunits. In addition to being expressed in the lens (LENS, CRYSTALLINE), alpha-crystallin B chain has been found in a variety of tissues such as HEART; BRAIN; MUSCLE; and KIDNEY. Accumulation of the protein in the brain is associated with NEURODEGENERATIVE DISEASES such as CREUTZFELDT-JAKOB SYNDROME and ALEXANDER DISEASE.
Congenital or developmental anomaly in which the eyeballs are abnormally small.
A family of Urodela consisting of 15 living genera and about 42 species and occurring in North America, Europe, Asia, and North Africa.
A group of homologous proteins which form the intermembrane channels of GAP JUNCTIONS. The connexins are the products of an identified gene family which has both highly conserved and highly divergent regions. The variety contributes to the wide range of functional properties of gap junctions.
A ring of tissue extending from the scleral spur to the ora serrata of the RETINA. It consists of the uveal portion and the epithelial portion. The ciliary muscle is in the uveal portion and the ciliary processes are in the epithelial portion.
The acidic subunit of beta-crystallins.
The use of statistical and mathematical methods to analyze biological observations and phenomena.
Infection of the cornea by an ameboid protozoan which may cause corneal ulceration leading to blindness.
Loss of epithelial tissue from the surface of the cornea due to progressive erosion and necrosis of the tissue; usually caused by bacterial, fungal, or viral infection.
Diseases of the cornea.
The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.
A form of fluorescent antibody technique commonly used to detect serum antibodies and immune complexes in tissues and microorganisms in specimens from patients with infectious diseases. The technique involves formation of an antigen-antibody complex which is labeled with fluorescein-conjugated anti-immunoglobulin antibody. (From Bennington, Saunders Dictionary & Encyclopedia of Laboratory Medicine and Technology, 1984)
An enzyme that catalyzes reversibly the oxidation of an aldose to an alditol. It possesses broad specificity for many aldoses. EC
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A technique for maintenance or growth of animal organs in vitro. It refers to three-dimensional cultures of undisaggregated tissue retaining some or all of the histological features of the tissue in vivo. (Freshney, Culture of Animal Cells, 3d ed, p1)
A network of cross-linked hydrophilic macromolecules used in biomedical applications.
Method of making images on a sensitized surface by exposure to light or other radiant energy.
Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.
A species of newt in the Salamandridae family in which the larvae transform into terrestrial eft stage and later into an aquatic adult. They occur from Canada to southern United States. Viridescens refers to the greenish color often found in this species.
Clouding or loss of transparency of the posterior lens capsule, usually following CATARACT extraction.
A genus of free-living soil amoebae that produces no flagellate stage. Its organisms are pathogens for several infections in humans and have been found in the eye, bone, brain, and respiratory tract.
The diversion of RADIATION (thermal, electromagnetic, or nuclear) from its original path as a result of interactions or collisions with atoms, molecules, or larger particles in the atmosphere or other media. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Diseases affecting the eye.
A noninflammatory, usually bilateral protrusion of the cornea, the apex being displaced downward and nasally. It occurs most commonly in females at about puberty. The cause is unknown but hereditary factors may play a role. The -conus refers to the cone shape of the corneal protrusion. (From Dorland, 27th ed)
Apparatus, devices, or supplies intended for one-time or temporary use.
Congenital absence of or defects in structures of the eye; may also be hereditary.
Polymerized methyl methacrylate monomers which are used as sheets, moulding, extrusion powders, surface coating resins, emulsion polymers, fibers, inks, and films (From International Labor Organization, 1983). This material is also used in tooth implants, bone cements, and hard corneal contact lenses.
A scientific tool based on ULTRASONOGRAPHY and used not only for the observation of microstructure in metalwork but also in living tissue. In biomedical application, the acoustic propagation speed in normal and abnormal tissues can be quantified to distinguish their tissue elasticity and other properties.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.
An alternative to REFRACTIVE SURGICAL PROCEDURES. A therapeutic procedure for correcting REFRACTIVE ERRORS. It involves wearing CONTACT LENSES designed to force corrective changes to the curvature of the CORNEA that remain after the lenses are removed. The effect is temporary but is maintained by wearing the therapeutic lenses daily, usually during sleep.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
Methods and procedures for the diagnosis of diseases of the eye or of vision disorders.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
A surgical specialty concerned with the structure and function of the eye and the medical and surgical treatment of its defects and diseases.
Centers for storing various parts of the eye for future use.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
The methyl esters of methacrylic acid that polymerize easily and are used as tissue cements, dental materials, and absorbent for biological substances.
That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.
Damage or trauma inflicted to the eye by external means. The concept includes both surface injuries and intraocular injuries.
A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.
The white, opaque, fibrous, outer tunic of the eyeball, covering it entirely excepting the segment covered anteriorly by the cornea. It is essentially avascular but contains apertures for vessels, lymphatics, and nerves. It receives the tendons of insertion of the extraocular muscles and at the corneoscleral junction contains the canal of Schlemm. (From Cline et al., Dictionary of Visual Science, 4th ed)
Measurement of distances or movements by means of the phenomena caused by the interference of two rays of light (optical interferometry) or of sound (acoustic interferometry).
Behavior of LIGHT and its interactions with itself and materials.
Water swollen, rigid, 3-dimensional network of cross-linked, hydrophilic macromolecules, 20-95% water. They are used in paints, printing inks, foodstuffs, pharmaceuticals, and cosmetics. (Grant & Hackh's Chemical Dictionary, 5th ed)
A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The only family of the order SCANDENTIA, variously included in the order Insectivora or in the order Primates, and often in the order Microscelidea, consisting of five genera. They are TUPAIA, Ananthana (Indian tree shrew), Dendrogale (small smooth-tailed tree shrew), Urogale (Mindanao tree shrew), and Ptilocercus (pen-tailed tree shrew). The tree shrews inhabit the forest areas of eastern Asia from India and southwestern China to Borneo and the Philippines.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
Methods of creating machines and devices.
Maf transcription factors are a family of basic-leucine zipper transcription factors that are closely related to V-MAF ONCOGENE PROTEIN. The C-MAF PROTO-ONCOGENE PROTEIN was the first mammalian Maf transcription factor identified, and now the family is known to include a variety of other Maf proteins such as MAFB TRANSCRIPTION FACTOR; MAFF TRANSCRIPTION FACTOR; MAFG TRANSCRIPTION FACTOR; and MAFK TRANSCRIPTION FACTOR.
Connections between cells which allow passage of small molecules and electric current. Gap junctions were first described anatomically as regions of close apposition between cells with a narrow (1-2 nm) gap between cell membranes. The variety in the properties of gap junctions is reflected in the number of CONNEXINS, the family of proteins which form the junctions.
The clear, watery fluid which fills the anterior and posterior chambers of the eye. It has a refractive index lower than the crystalline lens, which it surrounds, and is involved in the metabolism of the cornea and the crystalline lens. (Cline et al., Dictionary of Visual Science, 4th ed, p319)
A superorder in the class CEPHALOPODA, consisting of the orders Octopoda (octopus) with over 200 species and Vampyromorpha with a single species. The latter is a phylogenetic relic but holds the key to the origins of Octopoda.
The absence or restriction of the usual external sensory stimuli to which the individual responds.
The aperture in the iris through which light passes.
One of a group of nonenzymatic reactions in which aldehydes, ketones, or reducing sugars react with amino acids, peptides, or proteins. Food browning reactions, such as those that occur with cooking of meats, and also food deterioration reactions, resulting in decreased nutritional value and color changes, are attributed to this reaction type. The Maillard reaction is studied by scientists in the agriculture, food, nutrition, and carbohydrate chemistry fields.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.
Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.
The condition of where images are correctly brought to a focus on the retina.
Personal devices for protection of the eyes from impact, flying objects, glare, liquids, or injurious radiation.
Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Proteins encoded by homeobox genes (GENES, HOMEOBOX) that exhibit structural similarity to certain prokaryotic and eukaryotic DNA-binding proteins. Homeodomain proteins are involved in the control of gene expression during morphogenesis and development (GENE EXPRESSION REGULATION, DEVELOPMENTAL).
The outer of the three germ layers of an embryo.
Processes and properties of the EYE as a whole or of any of its parts.
Measurement of light given off by fluorescein in order to assess the integrity of various ocular barriers. The method is used to investigate the blood-aqueous barrier, blood-retinal barrier, aqueous flow measurements, corneal endothelial permeability, and tear flow dynamics.
Experimentally produced harmful effects of ionizing or non-ionizing RADIATION in CHORDATA animals.
Stratified squamous epithelium that covers the outer surface of the CORNEA. It is smooth and contains many free nerve endings.
Elements of limited time intervals, contributing to particular results or situations.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A biocompatible, hydrophilic, inert gel that is permeable to tissue fluids. It is used as an embedding medium for microscopy, as a coating for implants and prostheses, for contact lenses, as microspheres in adsorption research, etc.
Filaments 7-11 nm in diameter found in the cytoplasm of all cells. Many specific proteins belong to this group, e.g., desmin, vimentin, prekeratin, decamin, skeletin, neurofilin, neurofilament protein, and glial fibrillary acid protein.
Deeply perforating or puncturing type intraocular injuries.
Sterile solutions that are intended for instillation into the eye. It does not include solutions for cleaning eyeglasses or CONTACT LENS SOLUTIONS.
Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.
Removal of the whole or part of the vitreous body in treating endophthalmitis, diabetic retinopathy, retinal detachment, intraocular foreign bodies, and some types of glaucoma.
The disodium salt of selenious acid. It is used therapeutically to supply the trace element selenium and is prepared by the reaction of SELENIUM DIOXIDE with SODIUM HYDROXIDE.
Electrophoresis in which a second perpendicular electrophoretic transport is performed on the separate components resulting from the first electrophoresis. This technique is usually performed on polyacrylamide gels.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Suppurative inflammation of the tissues of the internal structures of the eye frequently associated with an infection.
Surgical removal of a section of the iris.
A tripeptide with many roles in cells. It conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.
An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.
The professional practice of primary eye and vision care that includes the measurement of visual refractive power and the correction of visual defects with lenses or glasses.
Inanimate objects that become enclosed in the eye.
Proteins which maintain the transcriptional quiescence of specific GENES or OPERONS. Classical repressor proteins are DNA-binding proteins that are normally bound to the OPERATOR REGION of an operon, or the ENHANCER SEQUENCES of a gene until a signal occurs that causes their release.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
The physiological renewal, repair, or replacement of tissue.
Direct contact of a cell with a neighboring cell. Most such junctions are too small to be resolved by light microscopy, but they can be visualized by conventional or freeze-fracture electron microscopy, both of which show that the interacting CELL MEMBRANE and often the underlying CYTOPLASM and the intervening EXTRACELLULAR SPACE are highly specialized in these regions. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p792)
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
The presence of an infectious agent on instruments, prostheses, or other inanimate articles.
Disorder occurring in the central or peripheral area of the cornea. The usual degree of transparency becomes relatively opaque.
The distance between the anterior and posterior poles of the eye, measured either by ULTRASONOGRAPHY or by partial coherence interferometry.
A polyhydric alcohol with about half the sweetness of sucrose. Sorbitol occurs naturally and is also produced synthetically from glucose. It was formerly used as a diuretic and may still be used as a laxative and in irrigating solutions for some surgical procedures. It is also used in many manufacturing processes, as a pharmaceutical aid, and in several research applications.
Refers to animals in the period of time just after birth.
Partial or total replacement of all layers of a central portion of the cornea.
Each of the upper and lower folds of SKIN which cover the EYE when closed.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
The use of photothermal effects of LASERS to coagulate, incise, vaporize, resect, dissect, or resurface tissue.
A family of sequence-related proteins similar to HMGB1 PROTEIN that contains specific HMG-BOX DOMAINS.
The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.
A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.
OPPORTUNISTIC INFECTIONS with the soil fungus FUSARIUM. Typically the infection is limited to the nail plate (ONYCHOMYCOSIS). The infection can however become systemic especially in an IMMUNOCOMPROMISED HOST (e.g., NEUTROPENIA) and results in cutaneous and subcutaneous lesions, fever, KERATITIS, and pulmonary infections.
Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.
The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The sum of the weight of all the atoms in a molecule.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Rendering pathogens harmless through the use of heat, antiseptics, antibacterial agents, etc.
The complex processes of initiating CELL DIFFERENTIATION in the embryo. The precise regulation by cell interactions leads to diversity of cell types and specific pattern of organization (EMBRYOGENESIS).
The plan and delineation of prostheses in general or a specific prosthesis.
The use of an aberrometer to measure eye tissue imperfections or abnormalities based on the way light passes through the eye which affects the ability of the eye to focus properly.
A species of baboon in the family CERCOPITHECIDAE, which has a well-studied trilevel social structure consisting of troops, bands, and clans.
Agents causing contraction of the pupil of the eye. Some sources use the term miotics only for the parasympathomimetics but any drug used to induce miosis is included here.
Bleeding in the anterior chamber of the eye.
Visual impairments limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, color vision, or peripheral vision. These may result from EYE DISEASES; OPTIC NERVE DISEASES; VISUAL PATHWAY diseases; OCCIPITAL LOBE diseases; OCULAR MOTILITY DISORDERS; and other conditions (From Newell, Ophthalmology: Principles and Concepts, 7th ed, p132).
A naturally occurring product of plants obtained following reduction of GALACTOSE. It appears as a white crystalline powder with a slight sweet taste. It may form in excess in the lens of the eye in GALACTOSEMIAS, a deficiency of GALACTOKINASE.
The mucous membrane that covers the posterior surface of the eyelids and the anterior pericorneal surface of the eyeball.
The protein components of ferritins. Apoferritins are shell-like structures containing nanocavities and ferroxidase activities. Apoferritin shells are composed of 24 subunits, heteropolymers in vertebrates and homopolymers in bacteria. In vertebrates, there are two types of subunits, light chain and heavy chain. The heavy chain contains the ferroxidase activity.
A subclass of SOX transcription factors that are expressed in neuronal tissue where they may play a role in the regulation of CELL DIFFERENTIATION. Members of this subclass are generally considered to be transcriptional activators.
Examination of the angle of the anterior chamber of the eye with a specialized optical instrument (gonioscope) or a contact prism lens.
An objective determination of the refractive state of the eye (NEARSIGHTEDNESS; FARSIGHTEDNESS; ASTIGMATISM). By using a RETINOSCOPE, the amount of correction and the power of lens needed can be determined.
Preparation for electron microscopy of minute replicas of exposed surfaces of the cell which have been ruptured in the frozen state. The specimen is frozen, then cleaved under high vacuum at the same temperature. The exposed surface is shadowed with carbon and platinum and coated with carbon to obtain a carbon replica.
Shiny, flexible bands of fibrous tissue connecting together articular extremities of bones. They are pliant, tough, and inextensile.
A group of inherited enzyme deficiencies which feature elevations of GALACTOSE in the blood. This condition may be associated with deficiencies of GALACTOKINASE; UDPGLUCOSE-HEXOSE-1-PHOSPHATE URIDYLYLTRANSFERASE; or UDPGLUCOSE 4-EPIMERASE. The classic form is caused by UDPglucose-Hexose-1-Phosphate Uridylyltransferase deficiency, and presents in infancy with FAILURE TO THRIVE; VOMITING; and INTRACRANIAL HYPERTENSION. Affected individuals also may develop MENTAL RETARDATION; JAUNDICE; hepatosplenomegaly; ovarian failure (PRIMARY OVARIAN INSUFFICIENCY); and cataracts. (From Menkes, Textbook of Child Neurology, 5th ed, pp61-3)
The pressure of the fluids in the eye.
An in situ method for detecting areas of DNA which are nicked during APOPTOSIS. Terminal deoxynucleotidyl transferase is used to add labeled dUTP, in a template-independent manner, to the 3 prime OH ends of either single- or double-stranded DNA. The terminal deoxynucleotidyl transferase nick end labeling, or TUNEL, assay labels apoptosis on a single-cell level, making it more sensitive than agarose gel electrophoresis for analysis of DNA FRAGMENTATION.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
A six carbon compound related to glucose. It is found naturally in citrus fruits and many vegetables. Ascorbic acid is an essential nutrient in human diets, and necessary to maintain connective tissue and bone. Its biologically active form, vitamin C, functions as a reducing agent and coenzyme in several metabolic pathways. Vitamin C is considered an antioxidant.
The science dealing with the establishment and maintenance of health in the individual and the group. It includes the conditions and practices conducive to health. (Webster, 3d ed)
An exotic species of the family CYPRINIDAE, originally from Asia, that has been introduced in North America. They are used in embryological studies and to study the effects of certain chemicals on development.
An enzyme that catalyzes the active transport system of sodium and potassium ions across the cell wall. Sodium and potassium ions are closely coupled with membrane ATPase which undergoes phosphorylation and dephosphorylation, thereby providing energy for transport of these ions against concentration gradients.
A genus of tree shrews of the family TUPAIIDAE which consists of about 12 species. One of the most frequently encountered species is T. glis. Members of this genus inhabit rain forests and secondary growth areas in southeast Asia.
The development of anatomical structures to create the form of a single- or multi-cell organism. Morphogenesis provides form changes of a part, parts, or the whole organism.
A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.
An intermediate filament protein found in most differentiating cells, in cells grown in tissue culture, and in certain fully differentiated cells. Its insolubility suggests that it serves a structural function in the cytoplasm. MW 52,000.
A family of small polypeptide growth factors that share several common features including a strong affinity for HEPARIN, and a central barrel-shaped core region of 140 amino acids that is highly homologous between family members. Although originally studied as proteins that stimulate the growth of fibroblasts this distinction is no longer a requirement for membership in the fibroblast growth factor family.
Organic siloxanes which are polymerized to the oily stage. The oils have low surface tension and density less than 1. They are used in industrial applications and in the treatment of retinal detachment, complicated by proliferative vitreoretinopathy.
Cysteine proteinase found in many tissues. Hydrolyzes a variety of endogenous proteins including NEUROPEPTIDES; CYTOSKELETAL PROTEINS; proteins from SMOOTH MUSCLE; CARDIAC MUSCLE; liver; platelets; and erythrocytes. Two subclasses having high and low calcium sensitivity are known. Removes Z-discs and M-lines from myofibrils. Activates phosphorylase kinase and cyclic nucleotide-independent protein kinase. This enzyme was formerly listed as EC
Making measurements by the use of stereoscopic photographs.
An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.

From head to toes: the multiple facets of Sox proteins. (1/3497)

Sox proteins belong to the HMG box superfamily of DNA-binding proteins and are found throughout the animal kingdom. They are involved in the regulation of such diverse developmental processes as germ layer formation, organ development and cell type specifi-cation. Hence, deletion or mutation of Sox proteins often results in developmental defects and congenital disease in humans. Sox proteins perform their function in a complex interplay with other transcription factors in a manner highly dependent on cell type and promoter context. They exhibit a remarkable crosstalk and functional redundancy among each other.  (+info)

BMP7 acts in murine lens placode development. (2/3497)

Targeted inactivation of the Bmp7 gene in mouse leads to eye defects with late onset and variable penetrance (A. T. Dudley et al., 1995, Genes Dev. 9, 2795-2807; G. Luo et al., 1995, Genes Dev. 9, 2808-2820). Here we report that the expressivity of the Bmp7 mutant phenotype markedly increases in a C3H/He genetic background and that the phenotype implicates Bmp7 in the early stages of lens development. Immunolocalization experiments show that BMP7 protein is present in the head ectoderm at the time of lens placode induction. Using an in vitro culture system, we demonstrate that addition of BMP7 antagonists during the period of lens placode induction inhibits lens formation, indicating a role for BMP7 in lens placode development. Next, to integrate Bmp7 into a developmental pathway controlling formation of the lens placode, we examined the expression of several early lens placode-specific markers in Bmp7 mutant embryos. In these embryos, Pax6 head ectoderm expression is lost just prior to the time when the lens placode should appear, while in Pax6-deficient (Sey/Sey) embryos, Bmp7 expression is maintained. These results could suggest a simple linear pathway in placode induction in which Bmp7 functions upstream of Pax6 and regulates lens placode induction. At odds with this interpretation, however, is the finding that expression of secreted Frizzled Related Protein-2 (sFRP-2), a component of the Wnt signaling pathway which is expressed in prospective lens placode, is absent in Sey/Sey embryos but initially present in Bmp7 mutants. This suggests a different model in which Bmp7 function is required to maintain Pax6 expression after induction, during a preplacodal stage of lens development. We conclude that Bmp7 is a critical component of the genetic mechanism(s) controlling lens placode formation.  (+info)

Isolation and characterization of drosocrystallin, a lens crystallin gene of Drosophila melanogaster. (3/3497)

We have cloned the drosocrystallin gene (dcy) of Drosophila melanogaster, which encodes a major protein of the corneal lens, previously described in part by Komori et al. (1992, J. Cell Sci. 102, 191-201). Synthesis of the DCY protein starts weakly in 2-day-old pupae, reaches a peak at day 3 and day 4 of pupal development, and decreases very fast in young adults. The dcy mRNA is detected in the compound eyes as well as in the ocelli. The presence of a putative signal peptide and the extracellular location of DCY suggest that DCY is a secreted protein. Interestingly, the dcy gene shows sequence similarities to some insect cuticular proteins and is detected as well in two closely related Drosophila species, D. sechellia and D. simulans, and in one more distantly related species, D. virilis. This finding supports the hypothesis that Drosophila used the same strategy as vertebrates and mollusks, namely, recruiting a multifunctional protein for refraction in the lens, by a gene-sharing mechanism. Furthermore, it supports our intercalary evolution hypothesis, which suggests that the development of an elaborate structure (for example, a compound eye) from an original primitive form (an ancestral photoreceptor organ) can be achieved by recruiting novel genes into the original developmental pathway.  (+info)

Screening of Korean forest plants for rat lens aldose reductase inhibition. (4/3497)

Naturally occurring substances which can prevent and treat diabetic complications were sought by examining ethanol extracts prepared from Korean forest plants for their inhibitory effects on rat lens aldose reductase activity in vitro. Among the plants examined, Acer ginnala, Illicium religiosum and Cornus macrophylla exerted the most strong inhibitory activity on aldose reductase.  (+info)

Thapsigargin inhibits a potassium conductance and stimulates calcium influx in the intact rat lens. (5/3497)

1. An increase in lens cell calcium has long been associated with cortical cataract. Recently, it has been shown that thapsigargin induces a rise in lens cell calcium by release from endoplasmic reticulum stores. The effects of this rise on the optical and membrane characteristics of the lens were studied in the isolated rat lens. 2. The electrical characteristics of the isolated, perifused rat lens were measured using a two-internal microelectrode technique that permits measurement of plasma membrane conductance (Gm), membrane potential (Vm) and junctional conductance in the intact lens. 3. Thapsigargin (1 microM) induced a rapid overall depolarization of Vm that was accompanied by first a decrease and then an increase in Gm. 4. Replacing external Na+ with tetraethylammonium (TEA) abolished the decrease in Gm. However, a transient increase phase was still observed. 5. The changes in conductance were further characterized by measuring 22Na+ and 45Ca2+ influxes into the isolated lens. Thapsigargin (1 microM) induced a transient increase in 45Ca2+, but did not affect Na+ influx. 6. The Ca2+ channel blocker La3+ (10 microM) totally inhibited the thapsigargin-induced Ca2+ influx. It also blocked the increase in Gm observed in control and in Na+-free-TEA medium. In the absence of external calcium, thapsigargin induced a small depolarization in Vm. 7. These data indicate that thapsigargin induces both a decrease in K+ conductance and an increase in Ca2+ conductance. These probably result from release of stored Ca2+ and subsequent activation of store-operated Ca2+ channels (capacitative Ca2+ entry). 8. Thapsigargin application over the time course of these experiments (24 h) had no effect on junctional conductance or on the transparency of the lens.  (+info)

Modifications to rat lens major intrinsic protein in selenite-induced cataract. (6/3497)

PURPOSE: To identify modifications to rat lens major intrinsic protein (MIP) isolated from selenite-induced cataract and to determine whether m-calpain (EC is responsible for cleavage of MIP during cataractogenesis. METHODS: Cataracts were induced in rats by a single injection of sodium selenite. Control and cataract lenses were harvested on day 16 and dissected into cortical and nuclear regions. Membranes were washed with urea buffer followed by NaOH. The protein was reduced/alkylated, delipidated, and cleaved with cyanogen bromide (CNBr). Cleavage products were fractionated by high-performance liquid chromatography (HPLC), and peptides were characterized by mass spectrometry and tandem mass spectrometry. MIP cleavage by m-calpain was carried out by incubation with purified enzyme, and peptides released from the membrane were analyzed by Edman sequencing. RESULTS: The intact C terminus, observed in the control nuclear and cataractous cortical membranes, was not observed in the cataractous nuclear membranes. Mass spectrometric analysis revealed heterogeneous cleavage of the C terminus of MIP in control and cataract nuclear regions. The major site of cleavage was between residues 238 and 239, corresponding to the major site of in vitro cleavage by m-calpain. However, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and mass spectrometric analysis indicated that in vivo proteolysis during cataract formation also included sites closer to the C terminus not produced by m-calpain in vitro. Evidence for heterogeneous N-terminal cleavage was also observed at low levels with no differences between control and cataractous lenses. The major site of phosphorylation was determined to be at serine 235. CONCLUSIONS: Specific sites of MIP N- and C-terminal cleavage in selenite-induced cataractous lenses were identified. The heterogeneous cleavage pattern observed suggests that m-calpain is not the sole enzyme involved in MIP C-terminal processing in rat lens nuclei.  (+info)

Anterior polar cataracts in CS rats: a predictor of mature cataract formation. (7/3497)

PURPOSE: The objective of this study was to characterize the morphology of the anterior opacities formed during recovery from posterior subcapsular cataract (PSC) in Royal College of Surgeons (RCS) rats. METHODS: Lenses from RCS rats at 8 and 12 weeks postnatal (n = 14 and 12, respectively) were examined under a dissecting microscope for the presence of anterior opacities. Lenses with anterior opacities were fixed, embedded in epoxy resin, and sectioned along the optic axis for light microscopy (LM) and transmission electron microscopy (TEM). RESULTS: At eight weeks postnatal, 21.5% of animals (3/14) had anterior cataracts. Light microscopy of 1- to 2-microm-thick sections revealed an anomalous layer of material located at the epithelium-fiber interface, which was identified as a zone of liquefaction by TEM. Epithelial cells had minor structural defects but were not necrotic. Anterior portions of elongating and cortical fibers under the zone of liquefaction were undisrupted, whereas their posterior portions had numerous vacuoles. The anterior opacities were classified as anterior polar cataracts (APCs) based on the location and type of morphologic damage in the affected lenses. At twelve weeks postnatal, 25% of animals (3/12) had APCs that involved prominent vesiculation of the anterior cortex. Ultrastructural examination showed that large vesicles were located between and inside anterior fibers and that most extracellular spaces were abnormally widened. Posteriorly, internalization of the PSC by new fiber growth was disordered and displayed vesiculation and density variations. In the bow region, LM revealed minor structural irregularities that were identified as groups of apparently degenerating fibers by TEM. CONCLUSIONS: APCs in RCS rats are caused by degeneration of elongating fibers in the bow region and subsequent damage in the superficial anterior cortex. The percentage of animals with APCs (25%) was consistent with the percentage of animals in which mature cataracts eventually develop. The morphologic changes, time of onset, and percentage of animals affected suggest that APC is the initial manifestation of mature cataract formation in RCS rats.  (+info)

Effect of dietary taurine supplementation on GSH and NAD(P)-redox status, lipid peroxidation, and energy metabolism in diabetic precataractous lens. (8/3497)

PURPOSE: To evaluate changes in glutathione and NAD(P)-redox status, taurine and malondialdehyde (MDA) levels, glucose utilization, and energy metabolism in diabetic precataractous lenses and to assess whether these changes can be prevented with dietary taurine supplementation. METHODS: The experimental groups included control and streptozotocin-diabetic rats with a 3-week duration of diabetes fed unsupplemented or taurine (1% or 5%)-supplemented diets. The levels of glucose, sorbitol, fructose, myo-inositol, oxidized glutathione (GSSG), glycolytic intermediates, malate, alpha-glycerophosphate, and adenine nucleotides were assayed in individual lenses spectrofluorometrically by enzymatic methods, reduced glutathione (GSH) spectrofluorometrically with O-phthaldialdehyde, MDA colorimetrically with N-methyl-2-phenylindole, and taurine by high-performance liquid chromatography. Free cytosolic NAD+/NADH and NADP+/NADPH ratios were calculated from the lactate dehydrogenase and malic enzyme systems. RESULTS: Sorbitol pathway metabolites and MDA were increased, and GSH and taurine levels were reduced in diabetic rats versus controls. The profile of glycolytic intermediates (an increase in glucose 6-phosphate, no change in fructose 6-phosphate and fructose 1,6-diphosphate, an increase in dihydroxyacetone phosphate, a decrease in 3-phosphoglycerate, phosphoenolpyruvate, and pyruvate, and no change in lactate), and a 9.2-fold increase in alpha-glycerophosphate suggest diabetes-induced inhibition of glycolysis. Free cytosolic NAD+/NADH ratios, ATP levels, ATP/ADP, and adenylate charge were reduced, whereas free cytosolic NADP+/NADPH ratios were elevated. Lens taurine levels in diabetic rats were not affected by supplementation with 1% taurine. With 5% taurine supplementation, they were increased approximately 2.2-fold higher than those in untreated diabetics but remained 3.4-fold lower than in controls. Lens GSH levels were similar in diabetic rats fed unsupplemented and 5% taurine-supplemented diets, whereas GSSG and MDA levels and GSSG/GSH ratios were reduced by 5% taurine supplementation. The decrease in free cytosolic NAD+/NADH, ATP/ADP, and adenylate energy charge were ameliorated by 5% taurine supplementation, whereas accumulation of sorbitol pathway intermediates, depletion of myoinositol, inhibition of glycolysis, a decrease in ATP and total adenine nucleotide, and an increase in free cytosolic NADP+/NADPH were not prevented. CONCLUSIONS: Dietary taurine supplementation ameliorates MDA levels, GSSG/GSH, and NAD+/NADH and fails to prevent the osmotically mediated depletion of GSH and taurine and the decrease in glucose utilization and ATP levels in diabetic precataractous lens. Dietary taurine supplementation cannot be regarded as an alternative to aldose reductase inhibition in eliminating antioxidant and metabolic deficits contributing to diabetes-associated cataractogenesis.  (+info)

TY - JOUR. T1 - Characterization of the bovine lens plasma membrane substrates for cAMP‐dependent protein kinase. AU - LOUIS, Charles F.. AU - JOHNSON, Ross. AU - JOHNSON, Keith. AU - TURNQUIST, Janet. PY - 1985/7. Y1 - 1985/7. N2 - cAMP‐dependent protein kinase, derived from either calf lens or bovine heart, promotes the phosphorylation of three lens plasma membrane proteins of molecular mass 28 kDa, 26 kDa and 18 kDa. Correlation of the maximal level of phosphorylation of these components with the Coomassie blue staining intensity of fractionated lens membranes suggests that the phosphorylation of the 28 kDa and 18 kDa components may be approximately stoichiometric. The protein kinase substrates could be dephosphorylated by a cardiac sarcoplasmic‐reticulum‐bound protein phosphatase activity. The 26 kDa component comigrated with MP26, the major lens membrane component that has been localized to the lens fiber cell junction. Treatment of phosphorylated lens membranes with chymotrypsin ...
Purpose: : FGF signaling controls numerous processes during cell lineage specification, organogenesis and terminal differentiation. In lens, FGF signaling was implicated as the key pathway that controls lens fiber cell differentiation, but little is known about its nuclear components such as DNA-binding transcription factors and its cross-talk with other signaling pathways that function downstream and/or in parallel with FGF signaling. Methods: : We employed a rat lens epithelial explant system and performed integrated RNA and microRNA expression profiling in cells induced to differentiate by FGF2 (100 ng/ml). The RNAs were isolated at 2, 4, 12 and 24 hours following the treatment. RNA expression profiling was conducted using rat Affymetrix 230 2.0 arrays. MicroRNA profiling was conducted using the rodent TaqMan Low Density Array v2 ABI system. Candidate microRNA targets were identified through a combination of TargetScan 5.0 and integrated prediction databases in miRWalk and by inverse ...
A quantitative analysis of cell division and cell elongation was carried out during lens morphogenesis in the rat. At 13 days of development elongating cells in the posterior part of the lens vesicle (presumptive fibre cells) have a lower mitotic activity than cells in the anterior vesicle. By 14 days these elongating cells do not divide. Thus at 14 days of development the lens can be separated into two compartments; a proliferation compartment in the anterior lens and an elongation compartment in the posterior lens.. The three main groups of lens-specific proteins, α-,β- and γ-crystallins, were localized by immunofiuorescence. Alpha-crystallin is the first crystallin to be detected and is localized in some lens pit cells at 12 days of development. By 14 days all lens cells contain α-crystallin. Beta- and β-crystallins are detected later at 12½ days and are localized in some cells situated primarily in the posterior part of the lens vesicle. At later stages of development these crystallins ...
Abstract: : Purpose: To study the distribution of SPARC (secreted protein acidic and rich in cysteine) in the murine lens. SPARC has been shown to be an essential factor in the development and maintenance of lens transparency in mice because all SPARC-null mice begin to form cataract within 1 month after birth. It is therefore important to identify the localization and cellular expression of SPARC in the murine lens. Method: Immunohistochemistry and immunoblot analyses were conducted on murine lens capsule and on lens cells from E14 to 2 yr; steady-state levels of SPARC mRNA in lens cells were determined by RT-PCR. Results: Lens epithelium produced abundant SPARC as early as E14; the protein remained at high levels up to 2 yr of age. By immunohistochemistry and RT-PCR, the lens fiber cells at the equator were shown to contain SPARC, but not the secondary fibers located inside the bow region. The lens capsule did not contain SPARC. SPARC protein was also identified in the vitreous. Proteolytic ...
Ablation of cataractous human eye lens tissue with carbon dioxiqe laser beam of wave-length 10.6 μm is investigated at power densities upto 20 KW/cm2 with interaction time in the rnge of 4-20 msec. It is found that the ablation initiates at a fluence of about 26 J/cm2 and thereafter the ablated volume of the tissue increases with the laser fluence with a decreasing slope. A well defined zone of coagulation necrosis borders the laser ablated region and its width increases with the power density and interaction time of the laser beam. From the thermal behaviour of the cataractous lens tissue, it is found that at the onset of ablation, tissue attains a temperature of about 270°C. To confine this temperature to a reasonably small volume, short duration laser pulses will be ideal for ablating the cataractous lens ...
TY - JOUR. T1 - Molecular aspects of lens cell differentiation. AU - Papaconstantinou, John. PY - 1967/1/1. Y1 - 1967/1/1. N2 - I have presented a series of observations on macromolecular interactions which occur during the terminal stages of lens cell differentiation. These are summarized in Fig. 2. Other cell types that undergo similar changes are the erythrocyte and skin cells (epidermis) during the process of keratinization. These other cells are also involved in the synthesis of highly specific proteins, and there are indications that molecular alterations similar to those described for the lens may also occur in these cells (26). Thus, elucidation of a specific series of macromolecular interactions such as those described may provide a basis for the biochemical definition of the terminal stages of cellular differentiation. Differentiation of the reticulocyte, for example, involves inactivation of the nucleus, stabilization of mRNA, and possibly a ribosomal breakdown such as I have ...
10. Kim ST, Koh JW. Mechanisms of apoptosis on human lens epithelium after ultraviolet light exposure. Korean journal of ophthalmology : KJO 2011; 25:196-201 ...
The developing lens is a powerful system for the study of tissue interactions and also the target of the medically important ocular disease cataract, a lens opacity that affects over 25 million individuals and is the leading cause of blindness worldwide (Asbell et al., 2005; Hejtmancik, 2008). The mature lens consists of two polarized cell types: a monolayer of lens epithelial (LE) cells and a mass of elongated and aligned lens fiber (LF) cells. The entire structure is covered by a lens capsule, a thick basement membrane secreted by LE and early LF cells in a polarized manner (Wederell and de longh, 2006). During development, the lens originates from a thickening of the head ectoderm that invaginates to form the lens pit, and then detaches to form the lens vesicle. Cells from the anterior lens vesicle differentiate into epithelial cells, while cells from the posterior lens vesicle elongate to form primary fiber cells. In later embryogenesis, LE cells continuously proliferate and differentiate ...
MP20 is an intrinsic membrane protein previously identified in mammalian lens fiber cells. To identify a possible role for this protein in the lens, the distribution of MP20 and connexin46 has now been examined. Western immunoblotting with an anti-peptide antibody generated to the C-terminal 8 amino acids of MP20 confirmed the presence of this protein in the lens of several different mammalian species. A monoclonal antibody 5H1 was prepared that, in Western blots of bovine lesn membranes, recognized the same component as an antibody to rat connexin46 (Cx46). The apparent molecular mass of this component decreased from 59 kDa to 55 kDa following treatment of lens membranes with alkaline phosphatase. A monoclonal antibody to connexin-related MP70 recognized a 70 kDa component in bovine lens membranes confirming the presence of these two different connexin proteins in bovine lens membranes. To localize MP20 and Cx46 in the bovine lens membrane, lens fiber cell bundles were immunofluorescently ...
The Fe-transport protein, transferrin (Tf), is synthesized and secreted by whole lenses and cultured lens epithelial cells. Because of Tfs central role in cell growth and proliferation, its participation in lens cell proliferation following cataract extraction was explored using a rabbit model of a …
Tissue lectins appear to be involved in a broad range of physiological processes, as reflected for the members of the family of galectins by referring to them as adhesion/growth-regulatory effectors. In order to clarify the significance of galectin presence, key challenges are to define their binding partners and the profile of localization. Having identified the chicken galectin-related interfiber protein (C-GRIFIN) as lens-specific protein present in the main body of adult lens, we here report its interaction with lens proteins in ligand blotting. The assumption for pairing with α-, β- and δ-crystallins was ascertained by mass spectrometric detection of their presence in eluted fractions obtained by affinity chromatography. Biochemical and immunohistochemical monitoring revealed protein presence from about 3-day-old embryos onwards, mostly in the cytoplasm of elongated posterior cells, later in secondary lens fiber cells. On the level of gene expression, its promoter was activated by ...
TY - JOUR. T1 - Non-invasive phakometric measurement of corneal and crystalline lens alignment in human eyes. AU - Dunne, Mark C.M.. AU - Davies, Leon N.. AU - Mallen, Edward A.H.. AU - Kirschkamp, Thomas. AU - Barry, Jean-Cyriaque. PY - 2005. Y1 - 2005. N2 - We describe a non-invasive phakometric method for determining corneal axis rotation relative to the visual axis (β) together with crystalline lens axis tilt (α) and decentration (d) relative to the corneal axis. This does not require corneal contact A-scan ultrasonography for the measurement of intraocular surface separations. Theoretical inherent errors of the method, evaluated by ray tracing through schematic eyes incorporating the full range of human ocular component variations, were found to be larger than the measurement errors (β , 0.67°, α , 0.72° and d , 0.08 mm) observed in nine human eyes with known ocular component dimensions. Intersubject variations (mean ± S.D.: β = 6.2 ± 3.4° temporal, α = 0.2 ± 1.8° temporal and ...
During development of the lens, epithelial cells at the lens equator begin a differentiation process to become secondary fibre cells. The differentiating cells elongate and migrate towards the centre of the lens where they envelop the older, central fibre cells. Differentiation into fibre cells is accompanied by the breakdown of all organelles, such as the mitochondria. All organelle degradation is completed and denucleation occurs at the border of the organelle free zone (OFZ) which contains the central, terminally differentiated, fibre cells. The differentiation pathway is not well characterised, though it is believed to have similarities to an attenuated form of apoptosis supported by the identification of apoptosis related genes, such as TNF, in the lens. This study continues the search for and characterisation of apoptosis related genes expressed during lens development, focusing on TNFs and their extended family. Reverse Transcriptase-(RT-) PCR was carried out, identifying a number of TNF ...
Results of electrical, dye-coupling and morphological studies have previously suggested that gap junctions mediate communication between the anterior epithelium of the lens and the underlying lens fiber cells. This connection is believed to permit metabolic cooperation between these dissimilar cell types and may be of particular importance to the fiber cells, which are thought incapable of autonomous ionic homeostasis. We reinvestigated the nature of the connection between epithelial and fiber cells of the embryonic chicken lens using fluorescence confocal microscopy and freeze-fracture analysis. In contrast to earlier studies, our data provided no support for gap-junction-mediated transport from the lens epithelium to the fibers. Fluorescent dyes loaded biochemically into the lens epithelium were retained there for more than one hour. There was a decrease in epithelial fluorescence over this period, but this was not accompanied by an increase in fiber cell fluorescence. Diffusional modeling ...
Two aquaporins have been detected in the crystalline lens. AQP1 is confined to the mitotic epithelial cell layer that lines the anterior surface (14), whereas AQP0 is characteristic of the terminally differentiated fiber cells (33) that constitute the bulk of the lens mass. Although AQP1 is at least 10-fold more active as a water channel than its fiber cell counterpart (23), no spontaneous lens pathology has been associated with AQP1 deficiency in humans (25) or mice (20). In this study, we have shown that AQP0 accounts for ∼80% of the water permeability of mouse lens fiber cell plasma membranes and that heterozygous loss of this MIP is sufficient to compromise lens transparency. These observations suggest that although the lens can compensate for loss of AQP1 function, there is no such redundancy for AQP0 deficiency.. The relative loss of water permeability recorded in Aqp0+/− mouse lenses was similar in magnitude to that measured in the kidney proximal tubules of Aqp1+/− mice (20). This ...
For more than a century, the lens has provided a relatively simple structure in which to study developmental mechanisms. Lens induction, where adjacent tissues signal the cell fate changes that result in lens formation, have been of particular interest. Embryological manipulations advancing our understanding have included the Spemann optic rudiment ablation experiments, optic vesicle transplantations as well as more contemporary work employing lineage tracers. All this has revealed that lens induction signaling is a multi-stage process involving multiple tissue interactions. More recently, molecular genetic techniques have been applied to an analysis of lens induction. This has led to the identification of signaling pathways required for lens induction and early lens development. These include the bone morphogenetic protein (Bmp) signaling pathways where Bmp4 and Bmp7 have been implicated. Though no fibroblast growth factor (Fgf) ligand has been implicated at present, the Fgf signaling pathway clearly
Human Lens Epithelial Cells (HLEpiC) from Creative Bioarray are isolated from the human lens. HLEpiC are cryopreserved at primary culture and delivered frozen. Each vial contains >5 x 10^5 cells in 1 ml volume. HLEpiC are characterized by immunofluorescent method with antibodies to cytokeratin-18, cytokeratin-19 and fibronectin. HLEpiC are negative for HIV-1, HBV, HCV, mycoplasma, bacteria, yeast and fungi. HLEpiC are guaranteed to further culture in the conditions provided by Creative Bioarray ...
An elevated level of Ca2+ is an important factor in cataract, yet precisely how Ca2+ enters the lens is unknown. Lens epithelial cells contain a range of G-protein-coupled receptors and receptor tyrosine kinases that induce increases in intracellular Ca2+. Receptor-associated Ca2+ influx is, therefore, likely to be an important route for Ca2+ influx to the lens. The authors investigated stimulated and passive Ca2+ influx in in situ human lens epithelium. Ca2+ changes in equatorial (E) and central anterior (CA) epithelial cells were monitored with the use of a Ca2+ indicator (Fluo4) and confocal microscopy. Gene expression was monitored by RT-PCR and immunoblotting. Adenosine triphosphate (ATP) induced Ca2+ responses that were smaller in CA than E. Ca2+ store depletion, using ATP (100 µM) or thapsigargin (1 µM), revealed greater relative store capacity and Ca2+ influx in E. Ca2+ influx was blocked by La3+ (0.5 µM) in both regions. Unstimulated Ca2+ influx was greater in E than CA. Greater ...
Previously, the researchers were not able to address the genes possible role in mouse eye formation because inactivation of Six3 significantly disrupted development of the area of the brain where the eye normally forms. The St. Jude team overcame this problem by taking advantage of Cre/loxP-technology, which allowed them to choose the time and place in which to remove Six3 function from specific cells. This permitted the investigators to remove Six3 activity from the presumptive lens ectoderm (PLE)--the area of the developing head where the lens will ultimately form in response to a series of biochemical signals. Following this systematic approach, the St. Jude team demonstrated that Six3 plays its important role in the PLE. The investigators also showed that a key consequence of removing Six3 during early development is that the PLE fails to undergo its normal thickening, an initial critical step in lens formation.. Our discovery helps to better unravel the regulatory pathway that controls ...
The topology of the BPN classifier.. \n. In this chapter, a three-layer BPN is used for classifying AUV failure conditions. The topology of the BPN classifier is shown in Figure 7 [26]. The input layer has R neurons, equal to the dimension of the feature vectors \n\nI\n=\n\n\n\nI\n1\n\n1\n\n\n\n\n\nI\nr\n\n1\n\n\n\n…\n\nI\nR\n\n1\n\n\n\nT\n\n\n , where superscript 1 indicates the first layer. The hidden layer has J neurons, and the output layer has P neurons, equal to the number of AUV conditions \n\nO\n=\n\n\n\nO\n1\n\n3\n\n\n\n\n\nO\np\n\n3\n\n\n\n…\n\nO\nP\n\n3\n\n\n\nT\n\n\n , where superscript 3 indicates the third layer. \n\n\nw\npj\n\n3\n\n\n\n and \n\n\nw\njr\n\n2\n\n\n\n denote the weight from the hidden to the output layer and from the input to the hidden layer, respectively. \n\n\nb\n\n3\n\n\n\n and \n\n\nb\n\n2\n\n\n\n denote the bias in the third and second layers, respectively. \n\n\ni\n\nn\n\n\n\n and \n\n\no\n\nn\n\n\n\n are the input value and the activation of a neuron in ...
My research focuss on two areas of ocular disease-cataract and glaucoma. As it relates to lens biology, I am currently studying growth factor initiated signaling pathways critical for the regulation of lens epithelial cell proliferation, elongation and differentiation. A specific focus in this broad area of research is to elucidate the role (s) played by small GTP-binding proteins of the Ras and Rho family, in signaling pathways important in normal lens function and physiology, and in processes underlying cataractogenesis.
A human eye model is proposed using a single equation for GRIN profile representation in crystalline lens. The role of GRIN in providing optical power and maintaining image quality during accommodation is studied and simulated.. © 2006 Optical Society of America. PDF Article ...
TY - JOUR. T1 - Regional differences in store-operated Ca2+ entry in the epithelium of the intact human lens. AU - Rhodes, Jeremy D.. AU - Russell, Sarah L.. AU - Illingworth, Christopher D.. AU - Duncan, George. AU - Wormstone, I. Michael. PY - 2009/9. Y1 - 2009/9. N2 - An elevated level of Ca2+ is an important factor in cataract, yet precisely how Ca2+ enters the lens is unknown. Lens epithelial cells contain a range of G-protein-coupled receptors and receptor tyrosine kinases that induce increases in intracellular Ca2+. Receptor-associated Ca2+ influx is, therefore, likely to be an important route for Ca2+ influx to the lens. The authors investigated stimulated and passive Ca2+ influx in in situ human lens epithelium. Ca2+ changes in equatorial (E) and central anterior (CA) epithelial cells were monitored with the use of a Ca2+ indicator (Fluo4) and confocal microscopy. Gene expression was monitored by RT-PCR and immunoblotting. Adenosine triphosphate (ATP) induced Ca2+ responses that were ...
Journal Français dOphtalmologie - Vol. 37 - N° 10 - p. 773-779 - Spectral transmission of the pig lens: Effect of ultraviolet A + B radiation - EM|consulte
Mutations in the small heat shock proteins α-crystallins have been linked to autosomal dominant cataracts in humans. Extensive studies in vitro have revealed a spectrum of alterations to the structure and function of these proteins including shifts in the size of the oligomer, modulation of subunit exchange and modification of their affinity to client proteins. Although mouse models of these mutants were instrumental in identifying changes in cellular proliferation and lens development, a direct comparative analysis of their effects on lens proteostasis has not been performed. Here, we have transgenically expressed cataract-linked mutants of αA- and αB-crystallin in the zebrafish lens to dissect the underlying molecular changes that contribute to the loss of lens optical properties. Zebrafish lines expressing these mutants displayed a range of morphological lens defects. Phenotype penetrance and severity were dependent on the mutation even in fish lines lacking endogenous α-crystallin. The ...
Purpose: To model the time evolution of active caspase-3 protein expression in a healthy lens, and in a lens exposed to UVR-300 nm (UVR-B). To develop an automated method to classify the fluorescent signal of biomarkers in the lens epithelial cells.. Methods: Six-week old Sprague-Dawley rats were used. Firstly, expression of active caspase-3 was studied in the lens epithelium of healthy rats. Secondly, rats were unilaterally exposed in vivo to 1 kJ/m2 UVR-B for 15 minutes. At 0.5, 8, 16, and 24 hours after the UVR-B exposure, the exposed and the contralateral non-exposed lenses were removed. Immunohistochemistry was done on three mid-sagittal sections from each lens. The florescent labelling for active caspase-3 in each lens section was counted three times. The time evolution of active caspase-3 expression in response to UVR-B exposure was modelled as a function of cell position in the lens epithelium. An automated objective method was developed to quantify the lens epithelial cells and to ...
The Mammalian Phenotype (MP) Ontology is a community effort to provide standard terms for annotating phenotypic data. You can use this browser to view terms, definitions, and term relationships in a hierarchical display. Links to summary annotated phenotype data at MGI are provided in Term Detail reports.
The procedures for culturing Nakano and normal mouse lens epithelium were developed in the NEI laboratory by Dr. Y. Tsunematsu and Dr. Paul Russell. My goals were to grow both kinds of cells in culture and to record the morphological development of the cultures. I also hoped to examine two characteristics of the cultures for significant differences between Nakano and normal cells: the growth characteristics, and the glucose-6-phosphate dehydrogenase/hexokinase ratio, (an indication of the type of cellular metabolism ...
My laboratory investigates mammalian eye development with the aim to identify and functionally characterize genes associated with human ocular diseases. Our present efforts are directed towards understanding development of the ocular lens - a transparent tissue that focuses light on the retina for visual acuity. Lens transparency is the outcome of a specialized developmental program involving differentiation of anteriorly localized epithelial cells into posteriorly localized elongated fiber cells that make up bulk of the lens tissue. Terminally differentiated lens fiber cells express high levels of structural proteins termed crystallins and completely degrade their nuclei and organelles - properties that are necessary for rendering the lens transparent. Perturbation of this differentiation program results in opacification of the lens causing an ocular disease termed cataract. We take an integrated approach using systems biology and mouse developmental genetics to identify novel genes associated ...
We have demonstrated a distinct association between ocular lens fluorescence and the estimated risk of ischemic heart disease (IHD) calculated on the basis of a number of non-ocular health parametres. The relationship was attributable to the effects of glucose metabolism and tobacco smoking on both the aging process of the lens and IHD risk. Glucose metabolism and tobacco smoking are well-known risk factors for both lens aging [27] and cardiovascular disease [31, 2]. Glucose and substances in tobacco smoke, glycotoxins, induce irreversible changes on proteins through formation of advanced glycation end products leading to impaired collagen function such as stiffening of arterial walls [32, 33, 13]. In the lens, these protein changes are marked features of the aging process and they can be quantified non-invasively and in vivo by lens autofluorometry. The effect on the rest of the body excerted by these factors can, however, not be assessed in vivo unless invasive procedures are used.. Ischemic ...
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Read Connexins in Lens Development and Cataractogenesis, The Journal of Membrane Biology on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Figure 6. Expression pattern of p57Kip2. In situ hybridizations were done on ocular sections of nontransgenic (marked +/+; A,B), OVE1934 (C-F), and OVE1935 (G-J) embryos using 35S-labeled p5735 riboprobe. In wild-type lenses, p57Kip2 expression is upregulated in the equatorial region where fiber cell differentiation is initiated (A,B, red arrowheads). In lenses of homozygous (Tg/Tg) transgenic mice from OVE1934 and OVE1935 embryos, the zone of p57Kip2 induction has migrated toward the posterior of the lens (E,F,I,J, red arrowheads). Expression of p57 was nearly normal in heterozygous (Tg/+) embryos from these same families (C,D,G,H). The cornea (c), lens epithelial cells (le), lens fiber cells (lf), and retina (r) are identified in A. The scale bar (I) represents 100 μm.. ...
J:136711 Zhao H, Yang T, Madakashira BP, Thiels CA, Bechtle CA, Garcia CM, Zhang H, Yu K, Ornitz DM, Beebe DC, Robinson ML, Fibroblast growth factor receptor signaling is essential for lens fiber cell differentiation. Dev Biol. 2008 Jun 15;318(2):276-88 ...
Eyes are the organs of vision. Through a complex process, they detect and focus light to create images. Vision begins when light rays are reflected off of an object and enters the eye through the cornea and then pupil. It then passes through the crystalline lens which refracts light to be focused on the retina. By changing shape, the lens functions to change the focal distance of the eye so it can focus on objects at various distances. When light hits the retina, tiny cells, rods, and cones, capture the light signals and convert them into electrochemical impulses in neurons. Rods communicate the objects shape by reading black and white and shades of gray. Cones communicate the color of the object. Working together, the rods and cones process the light. They then create an image by triggering nerve impulses that pass to the image centers in the brain via the optic nerve.. ...
A method of delivering a drug or other compound to the lens of the eye. A conduit through which a drug is introduced penetrates at least the outer lens capsule for drug delivery. When withdrawn, the aperture is self-sealing, thus minimizing trauma and minimizing the risk of cataract formation. The drug remains localized within the lens.
A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope (lens capsule), varying in degree from slight to complete opacity and obstructing the passage of light.. Early in the development, the power of the lens may be increased, causing near-sightedness (myopia), and the gradual yellowing and opacification of the lens may reduce the perception of blue colors.. Cataracts typically progress slowly to cause vision loss, and are potentially blinding if untreated. The condition usually affects both eyes, but almost always one eye is affected earlier than the other.. ...
Journal of Pediatric Ophthalmology and Strabismus | The authors describe a preterm infant who developed advanced retinopathy of prematurity bilaterally with a prominent tunica vasculosa lentis. Treatment with intravitreal bevacizumab resulted in regression of the tunica vasculosa lentis and posterior manifestations of the retinopathy of prematurity. RetCam imaging (Clarity Medical Systems, Pleasanton, CA) of the anterior segment was used to
PURPOSE To establish an electrical fingerprint for the gap junction channels between mammalian lens epithelial cells. METHODS The double whole cell patch clamp technique was applied to isolated cell pairs obtained from mouse lens epithelium and a continuous cell line of lens epithelial cells derived from the sheep lens (SLE 2.1). RESULTS The junctional conductance in mouse lens epithelial cells and in cultured SLE 2.1 cells was found to be moderately voltage dependent. SLE 2.1 cells were analyzed in more detail. The voltage dependence could be described by a Boltzmann distribution with Vo = +/- 63.1 mV and Gmin = 0.34. In cell pairs that exhibited spontaneously low junctional conductance, single channel events could be distinguished. Single gap junction channel currents had a linear current-voltage relationship. A frequency histogram of single channel conductances from eight cell pairs had three major peaks of 35, 60 and 97 pS. CONCLUSION The electrical properties of gap junction channels
We present an optimization method to retrieve the gradient index (GRIN) distribution of the in-vitro crystalline lens from optical path difference data extracted from OCT images. Three-dimensional OCT images of the crystalline lens are obtained in two orientations (with the anterior surface up and posterior surface up), allowing to obtain the lens geometry. The GRIN reconstruction method is based on a genetic algorithm that searches for the parameters of a 4-variable GRIN model that best fits the distorted posterior surface of the lens. Computer simulations showed that, for noise of 5 μm in the surface elevations, the GRIN is recovered with an accuracy of 0.003 and 0.010 in the refractive indices of the nucleus and surface of the lens, respectively. The method was applied to retrieve three-dimensionally the GRIN of a porcine crystalline lens in vitro. We found a refractive index ranging from 1.362 in the surface to 1.443 in the nucleus of the lens, an axial exponential decay of the GRIN profile ...
The optical properties of the lens are dependent upon the integrity of proteins within the fiber cells. During aging, crystallins, the major intra-cellular structural proteins of the lens, aggregate and become water-insoluble. Modifications to crystallins and the lens intermediate filaments have been implicated in this phenomenon. In this study, we examined changes to, and interactions between, human lens crystallins and intermediate filament proteins in lenses from a variety of age groups (0-86 years). Among the lens-specific intermediate filament proteins, filensin was extensively cleaved in all postnatal lenses, with truncated products of various sizes being found in both the lens cortical and nuclear extracts. Phakinin was also truncated and was not detected in the lens nucleus. The third major intermediate filament protein, vimentin, remained intact in lens cortical fiber cells across the age range except for an 86 year lens, where a single ~ 49 kDa breakdown product was observed. An ¿B-crystallin
Transcriptional regulator which is important for the differentiation and maintenance of meso-diencephalic dopaminergic (mdDA) neurons during development. In addition to its importance during development, it also has roles in the long-term survival and maintenance of the mdDA neurons. Activates NR4A2/NURR1-mediated transcription of genes such as SLC6A3, SLC18A2, TH and DRD2 which are essential for development of mdDA neurons. Acts by decreasing the interaction of NR4A2/NURR1 with the corepressor NCOR2/SMRT which acts through histone deacetylases (HDACs) to keep promoters of NR4A2/NURR1 target genes in a repressed deacetylated state. Essential for the normal lens development and differentiation. Plays a critical role in the maintenance of mitotic activity of lens epithelial cells, fiber cell differentiation and in the control of the temporal and spatial activation of fiber cell-specific crystallins. Positively regulates FOXE3 expression and negatively regulates PROX1 in the anterior lens epithelium,
The lens in the dyl mutant mice shows a persistent lens-ectodermal connection as well as degeneration and extrusion of lens materials after the initial differentiation of the fibres. Immunohistochemical investigation of the ontogeny of the lens crystallins in this developing mutant lens has been carried out using the indirect immunofluorescence ... read more staining method with antiserum to adult mouse lens total soluble proteins. The results have been compared with those for coisogenic normal lens used as a control. In both, the first positive reaction was detectable at identical stages of lens development. A rapid increase in the intensity of fluorescence, most marked in the elongating fibre progressing through the equatorial region to the epithelium, was recorded in the mutant as well as in the normal lens. However, the stalk leading to the lens epithelium did not show any reaction. Appearance of vacuoles in the lens nucleus and cortex marked the beginning of degeneration of fibres which ...
In the human eye, the crystalline lens is composed of a single-cell-layer epithelium in the front and a cortex that envelopes the nucleus. The epithelial cells elongate into cortical fiber cells and the ends are jointed at the front and the back, known as the sutures. The front suture is shaped as an upright Y and the posterior, an inverted Y. Superimposing the two Ys, what do you get? Yes, 6-points. This is the basic pattern. Often there are branches off the basic Ys. In other words, stars (in effect, point sources of light) should appear 6-pointed (with/without branches) to most of us. If you see 5 or 7 points, have your eyes examined ...
Cataract is a major ocular disease that causes blindness in many developing countries of the world. It is well established that various factors such as oxidative stress, UV, and other toxic agents can induce both in vivo and in vitro cataract formation. However, a common cellular basis for this induction has not been previously recognized. The present study of lens epithelial cell viability suggests such a general mechanism. When lens epithelial cells from a group of 20 cataract patients 12 to 94 years old were analyzed by terminal deoxynucleotidyl transferase (TdT) labeling and DNA fragmentation assays, it was found that all of these patients had apoptotic epithelial cells ranging from 4.4 to 41.8%. By contrast, in eight normal human lenses of comparable age, very few apoptotic epithelial cells were observed. We suggest that cataract patients may have deficient defense systems against factors such as oxidative stress and UV at the onset of the disease. Such stress can trigger lens epithelial ...
TY - JOUR. T1 - λ-crystallin related to dehydroascorbate reductase in the rabbit lens. AU - Suzuki, Takahiro. AU - Bando, Masayasu. AU - Oka, Mikako. AU - Tsukamoto, Hideo. AU - Akatsuka, Ichiko. AU - Kawai, Kenji. AU - Obazawa, Hajime. AU - Kobayashi, Shizuko. AU - Takehana, Makoto. PY - 2003/9. Y1 - 2003/9. N2 - Purpose: To evaluate the relationship of λ-crystallin to reduced nicotinamide adenine dinucleotide (NADH)-dependent dehydroascorbate (DHA) reductase found specifically in the rabbit lens. Methods: DHA reductase Fractions I-IV were separated from the λ/βL1-crystallin fraction of rabbit lens soluble protein by diethylaminoethyl (DEAE)-cellulose ion-exchange column chromatography, and then the enzyme was partially purified from Fraction II by rechromatography on the same ion-exchange column. The isolated DHA reductase fractions were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blotting, native isoelectric focusing and two-dimensional ...
The ocular lens is one of two lenses in the optical train of a microscope, the other being the objective lens. Located in the eyepiece, the ocular lens is the nearest lens to the observer's eye providing additional magnification and directing the image into the observer's eye.Total MagnificationThe total magnification of a microscope is the product of the magnification of the ocular lens and the objective lens. For example, a 10x ocular lens and a 40x objective lens produce a total magnification of 400x.Monocular vs. Binocular MicroscopesMonocular microscopes have one ocular lens, while binocular microscopes have two ocular lenses--one for...
In previous studies we have characterized a lens-specific intermediate filament (IF) protein, termed filensin. Filensin does not self-assemble into regular IFs but is known to associate with another 47-kD lens-specific protein which has been suggested to represent its assembly partner. To address this possibility, we cloned and sequenced the cDNA coding for the bovine 47-kD protein which we have termed phakinin (from the greek phi alpha kappa omicron sigma = phakos = lens). The predicted sequence comprises 406 amino acids and shows significant similarity (31.3% identity over 358 residues) to type I cytokeratins. Phakinin possesses a 95-residue, non-helical domain (head) and a 311 amino acid long alpha-helical domain punctuated with heptad repeats (rod). Similar to cytokeratin 19, phakinin lacks a COOH-terminal tail domain and it therefore represents the second known example of a naturally tailless IF protein. Confocal microscopy on frozen lens sections reveals that phakinin colocalizes with ...
Discussion. The aims of the present study were to comparatively identify parent crystallins of the crystallin fragments present in WS-α-crystallin, WS-HMW, and WI protein fractions of human cataractous (with nuclear opacity) and age matched normal lenses, and to identify post-translational modifications in crystallin species present in the WS-HMW and WI protein fractions of cataractous lenses. The rationale was that the results would distinguish cataract specific aggregated crystallin species from those that aggregate during aging in both WS-HMW and WI protein fractions.. The major findings of this study are: (1) the majority of aggregated species in the WS-HMW and in the WI protein fractions during aging and nuclear cataract development were fragments of αA- and αB-crystallin, (2) while the younger lenses contained only the C-terminally truncated αA- and αB-crystallin, the older normal lenses showed age related truncation of both N- and C- terminal regions in the crystallins, (3) in the ...
TY - JOUR. T1 - Heparins roles in stabilizing, potentiating, and transporting LEDGF into the nucleus. AU - Fatma, N.. AU - Singh, D. P.. AU - Shinohara, T.. AU - Chylack, Jr. PY - 2000/8/29. Y1 - 2000/8/29. N2 - PURPOSE. Lens epithelium-derived growth factor (LEDGF) is a 60-kDa protein that dramatically enhances cellular survival, growth, adhesiveness, and resistance to heat and oxidative stress. Full-size recombinant LEDGF is degraded during prokaryotic preparation. Heparins capacity to stabilize recombinant LEDGF in the face of various stresses (heat, pH, proteolysis), to potentiate its growth-enhancing properties, and to enable transport of LEDGF into the nucleus of mouse lens epithelial cells has been characterized. METHODS. LEDGF-cDNA was cloned in a pGEX-2T expression vector to produce a fusion protein, GST-LEDGF. Porcine heparin was used to stabilize GST-LEDGF. Heparin-Sepharose was used to characterize heparin-GST-LEDGF binding, and GST-LEDGF or heparin-GST-LEDGF was used to quantitate ...
Cataract is a clouding of the eye lens, and is the leading cause of blindness worldwide. Current treatments for glaucoma surgery the clouded eye lens of the eye by removing its support from the capsule and replace it with an artificial eye lens is included. Over 20 million glaucoma patients worldwide undergo this procedure every year.. Zhang noted that only 4 in 10,000 cataract patients are infants. However, In theory, this approach for any age, because the eye lens stem cells exist through life, should work, he said. Older patients stem cells to regenerate the lenses may need a bit of a boost, he said.. Current treatment for cataract artificial eye lens implantation, which is about 6 millimeters wide eye lens capsule needs to be a cut. Treatment can cause inflammation and destruction of LECs, which normally helps protect the eye lens from damage. Or a patients line of sight, which can result in the Cloud - Also, the scars of surgery or eye lens can lead to abnormal growth of cells.. In ...
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Import Data And Price Of FOLDABLE INTRA OCULAR LENS , www.eximpulse.com Eximpulse Services will provide you the latest and relevant market intelligence reports of FOLDABLE INTRA OCULAR LENS Import Data. You can find live data of maximum number of ports of India which is based on updated shipment data of Indian Customs. Only previous two days data will be seen on website. You can use this FOLDABLE INTRA OCULAR LENS import data for multiple kinds of analysis; lets say Import price, Quantity, market scenarios, Price trends, Duty optimization and many more. You can go through some of the sample shipment records for FOLDABLE INTRA OCULAR LENS import data mentioned above. Here on Eximpulse Services you will get all kind of free sample as well as detailed reports of Export/ Import data as per your requirement. To get in touch for any kind of enquiry related to free sample or detailed report contact on +91-120-408-4957, +91-120-408-4958,+91-120-428-4019.. Data post 2012 as per Notification No.18/2012 - ...
Development of the human lens begins at the 4 mm embryonic stage. Unlike the rest of the eye, which is derived mostly from the neural ectoderm, the lens is derived from the surface ectoderm. The first stage of lens differentiation takes place when the optic vesicle, which is formed from outpocketings in the neural ectoderm, comes in proximity to the surface ectoderm. The optic vesicle induces nearby surface ectoderm to form the lens placode. At the 4 mm stage, the lens placode is a single monolayer of columnar cells. As development progresses, the lens placode begins to deepen and invaginate. As the placode continues to deepen, the opening to the surface ectoderm constricts and the lens cells forms a structure known as the lens vesicle. By the 10 mm stage, the lens vesicle has completely separated from the surface ectoderm. After the 10mm stage, signals from the developing neural retina induces the cells closest to the posterior end of the lens vesicle begin to elongate toward the anterior end ...
Alpha-crystallin B chain is a protein that in humans is encoded by the CRYAB gene. It is part of the small heat shock protein family and functions as molecular chaperone that primarily binds misfolded proteins to prevent protein aggregation, as well as inhibit apoptosis and contribute to intracellular architecture. Post-translational modifications decrease the ability to chaperone. Defects in this gene/protein have been associated with cancer and neurodegenerative diseases such as Alzheimers disease and Parkinsons disease. Crystallins are separated into two classes: taxon-specific, or enzyme, and ubiquitous. The latter class constitutes the major proteins of vertebrate eye lens and maintains the transparency and refractive index of the lens. Since lens central fiber cells lose their nuclei during development, these crystallins are made and then retained throughout life, making them extremely stable proteins. Mammalian lens crystallins are divided into alpha, beta, and gamma families; beta and ...
IOLMaster 700 could measure the axial length in 99.2% of eyes while Lenstar could measure 97.1% of eyes. Axial lengths had a median absolute difference (MAD) of 0.02 mm; 1.8% of data pairs were clinically different. MAD of mean corneal radius was 0.02 mm with 8.4% outliers. MAD of crystalline lens equator position was 0.03 mm with 1.0% outliers. Mean astigmatic difference vector was 0.41 ± 0.30 D of cylinder. Using error propagation, we calculated the contribution of raytracing-computed IOL power difference as follows: axial length 29%, corneal radii 59%, crystalline lens equator position 12 ...
We have studied the survival requirements of developing lens epithelial cells to test the hypothesis that most cells are programmed to kill themselves unless they are continuously signaled by other cells not to do so. The lens cells survived for weeks in both explant cultures and high-density dissociated cell cultures in the absence of other cells or added serum or protein, suggesting that they do not require signals from other cell types to survive. When cultured at low density, however, they died by apoptosis, suggesting that they depend on other lens epithelial cells for their survival. Lens epithelial cells cultured at high density in agarose gels also survived for weeks, even though they were not in direct contact with one another, suggesting that they can promote one anothers survival in the absence of cell-cell contact. Conditioned medium from high density cultures promoted the survival of cells cultured at low density, suggesting that lens epithelial cells support one anothers survival ...
The mean refractive power of the eye (M) shifted slightly in the myopic direction in downward gaze in the no accommodation condition, consistent with previous findings (Ripple, 1952; Takeda et al., 1992). While the change in mean spherical refractive power was small (about −0.12 D) in magnitude, it was consistent and statistically significant. A study with monkeys observed a downward sag of the crystalline lens during centrally stimulated accommodation, presumably due to the action of gravity (Glasser & Kaufman, 1999). Another recent study reported that anterior chamber depth in human eyes may alter under the influence of gravity due to lens movement (Kasthurirangan, Markwell, Atchison, & Pope, 2011). Therefore, the myopic shift in refractive power in downward gaze that we observed may be the result of a small forward movement of the crystalline lens under the action of gravity. From previously reported modeling, we expect that the crystalline lens would be required to move about 100 μm ...
The goal of this project is to obtain quantitative images of the lens and the ciliary body to validate EVAS-II (Second generation Ex Vivo Accommodation Simulator). To accomplish this goal it was necessary to develop methods, instrumentation and image processing techniques to acquire 3D images in EVAS-II, using UBM (Ultrasound Bio Microscope), and to apply these techniques to non-human primate eyes. The lens studies included measurement of speed of sound in the lens to reconstruct accurate images of the lens, development of instrumentation to measure the un-distorted lens shape and development of a mathematical model to quantify the whole lens shape. Speed measurements showed that the speed of sound exhibits a gradient profile in the equatorial plane, similar to refractive index and protein distributions in the lens. Lens shape measurements showed that the UBM can be used to accurately measure thickness, diameter, cross-sectional area, volume and surface area of the lens. The ciliary body studies
An understanding of the vascular anatomy of the developing eye is helpful in making sense of the ocular findings. There are two components to fetal vasculature: the vascular meshwork that surrounds the lens during development (tunica vasculosa lentis), and the vascular connection of this lens meshwork that extends back through the gel filling the back part of the eye (vitreous) to the entry point of these vessels into the eye at the optic nerve (hyaloidal system, or primary vitreous).. Both the tunica vasculosa lentis and hyaloidal system are present during development but normally wither away before a pregnancy comes to term at 40 weeks of gestation. The findings in an eye with PFVS will depend on whether one or both of these components of the fetal vasculature is affected, and to what degree.. The disease itself is usually not progressive, but as the eye grows, the abnormal structural components of PFVS do not grow along with it; traction from these abnormal tissues on structures within the ...
The present invention provides an electrode array device for simultaneously detecting electrical potentials at five or more locations on the anterior surface of an eye. The device comprises a dielectric lens substrate having a concave inner surface conforming to the anterior surface of the eye, and at least five recording electrodes positioned in relation to the inner surface of the lens substrate so as to make electrical connection with the anterior surface of the eye when the lens substrate is placed on the anterior surface of eye. Each recording electrode is in electrically conductive communication with a corresponding conductive contact, there being one conductive contact for each recording electrode. Each conductive contact is adapted for operable connection to signal processor, and each conductive contact is electrically insulated from the anterior surface of the eye. A computational method for analyzing electrophysiological potentials recorded at five or more locations on the anterior surface of
Based on the role of retinoblastoma (Rb) in lens development and in the cell cycle reentry of muscle cells during limb regeneration, we have analyzed expression or Rb patterns in intact and lens regeneration-undergoing newt eyes. We find that in intact newt eye Rb is expressed in the retina as a gradient with higher levels in the photoreceptor layer and virtually no expression in the ganglion layer. In addition, a second gradient was detected within the photoreceptor layer with expression diminishing at the dorsal and ventral regions. In the intact lens, Rb is expressed in the lens epithelium and in the differentiating lens fibers at the bow region. During lens regeneration, Rb is expressed very strongly in the differentiating lens fibers, but not in the lens epithelium. Using an antibody specific to the hyperphosphorylated form of Rb, we detected the inactive protein only in the pigment epithelial cells of the iris. These distinct patterns might be related to the regenerative potential of the ...
The major purpose of this research was to characterize partially degraded proteins appearing in the ocular lens during aging and cataract, and to identify the responsible proteolytic activities. This research is significant, because increased protein degradation is associated with lens opacification and cataract. Determining the sites where lens proteins become truncated and identification of the responsible proteases is important because this information could be used to develop anticataract agents, such as new protease inhibitors. The methods used in this research include the application of several techniques employed in the field of proteomics. Two-dimensional electrophoresis (2-DE) was used to separate crystallins, the major proteins of the lens, and the modifications to these proteins were then determined by electrospray ionization mass spectrometry (ESI-MS). Lenses from mice of increasing age were used for these studies. Lp82 and m-calpain, the proteases hypothesized to cause the observed ...
TY - JOUR. T1 - Estrogen protects against radiation-induced cataractogenesis. AU - Dynlacht, Joseph. AU - Valluri, Shailaja. AU - Lopez, Jennifer. AU - Greer, Falon. AU - DesRosiers, Colleen. AU - Caperell-Grant, Andrea. AU - Mendonca, Marc. AU - Bigsby, Robert. PY - 2008/12. Y1 - 2008/12. N2 - Cataractogenesis is a complication of radiotherapy when the eye is included in the treatment field. Low doses of densely ionizing space radiation may also result in an increased risk of cataracts in astronauts. We previously reported that estrogen (17-β-estradiol), when administered to ovariectomized rats commencing 1 week before γ irradiation of the eye and continuously thereafter, results in a significant increase in the rate and incidence of cataract formation and a decreased latent period compared to an ovariectomized control group. We therefore concluded that estrogen accelerates progression of radiation-induced opacification. We now show that estrogen, if administered continuously, but commencing ...
More than 99% of the vertebrate ocular lens is comprised of terminally differentiated lens fiber cells. Two lens-specific intermediate filament-like proteins, the protein product of this gene (phakinin), and filensin, are expressed only after fiber cell differentiation has begun. Both proteins are found in a structurally unique cytoskeletal element that is referred to as the beaded filament (BF). Mutations in this gene have been associated with juvenile-onset, progressive cataracts and Dowling-Meara epidermolysis bullosa simplex. [provided by RefSeq, Jun 2009 ...
As they say, it would be a blurry world without eyeglasses. There are two different types of eyeglasses: those with converging lenses and those with diverging lenses. The distance from the focus to the lens is called the focal length. Converging lenses are convex with a positive focal length and diverging lenses are concave with a negative focal length.. Convex lenses are a series of prisms that get stronger as the outsides of the lens are reached and in this manner, light is refracted to converge on a point called the focus beyond the lens. Concave lenses diverge parallel rays, which appear to originate from a focus in front of the lens. Concave lenses are the ones that make a person&s eyes look bigger than they are by magnifying them. Convex are the most commonly used lenses for glasses.. Focal length is not stated directly in a prescription for eyeglasses. Instead, the refractive power is used to describe the extent to which a lens refracts light. The formula used to find the refractive ...
The first phase encompasses the transition from the bilaterian to the chordate ancestor (ps7-9). Here the visual system displays the strongest adaptive signals. This is, to our knowledge, the first genomic evidence that gives some credence to the idea that the visual system was the first complex sensory system to evolve in the lineage leading to the vertebrates [10, 11, 21]. However, the strong link between the present day zebrafish lens ontogeny and the origin of chordates (ps9) is somewhat puzzling if one looks at how lenses are distributed in the phylogeny among the extant deuterostomic lineages. First, a special type of calcitic lens is present in echinoderms (ps8) [5, 74]. In contrast, lens structures are not described in cephalochordates (ps9) [71]. Then again, lens structures are present in both Olfactores lineages (ps10); i.e., vertebrates and tunicates, although these lens stuctures have most likely evolved convergently [75, 76]. In this context, there are two scenarios that could ...
Dysfunctional Lens Syndrome (DLS) is the term for the natural aging process of the eyes. DLS typically starts with presbyopia (the need for reading glasses) and then progresses into the development of cataracts. As you age, the chemical makeup of your lens can change, making your eye lens progressively cloudy and thick. This is the development of cataracts. It is typically the second stage of DLS and it is part of the normal aging process. As the cataract grows in size and opacity your vision will become distorted. This change to your eyes crystalline lenses can occur even if you have had excellent vision your entire life. Luckily, today there are many options for vision improvement. ...
Multiple interspecies differences were detected between humans and seven other mammals in 15 of the 24 metabolites measured in the intact crystalline lens and lens perchloric acid extracts. Generally, the number of statistically significant metabolite differences among the various species, relative to the human, increase in the following order: cat or approximately dog greater than pig greater than rat greater than sheep greater than rabbit greater than cow. ...
... a lens crystalline; a heat shock protein; and a binding partner of cytoskeletal and chromatin structures to aid in ... Alpha-enolase, in addition, functions as a structural lens protein (tau-crystallin) in the monomeric form. Alternative splicing ...
Longitudinal evidence of crystalline lens thinning in children. Investigative Ophthalmology & Visual Science. 1995;36:1581-7. ... A video technique for phakometry of the human crystalline lens. Investigative Ophthalmology & Visual Science. 1992;33:1771-82. ... Optical and structural development of the crystalline lens in childhood. Investigative Ophthalmology & Visual Science. 1998;39: ... 2002;21:671-9. Walline JJ, Jones LA, Mutti DO, Zadnik K. A randomized trial of the effects of rigid contact lenses on myopia ...
Fernald, Russell D.; Wright, Stephen E. (1983). "Maintenance of optical quality during crystalline lens growth". Nature. 301 ( ... circadian renewal of photoreceptor opsins and mechanisms of crystalline lens focus (Rank Prize); 2) In social control of ... "Refractive index distribution and spherical aberration in the crystalline lens of the African cichlid fish Haplochromis burtoni ... Fernald next asked how fish lens quality was preserved during growth, identifying specific mechanisms, sharing the Rank Prize ...
Aphakic patients do not have a crystalline lens. The crystalline lens is often removed because of opacities called cataracts. ... Magnification size matched lenses that are used to correct aniseikonia are known as iseikonic lenses. Contact lenses may also ... Today, this is rarely a problem because when the lens is removed in cataract surgery, an intraocular lens, or IOL is left in ... and if the patient can tolerate wearing a contact lens.[citation needed] For reducing aniseikonia, similar to contact lens ...
Nuclear sclerosis of the crystalline lens was noticed in older dogs. Experiments into newborn macaque monkeys have revealed ...
One of Hunain ibn Ishaq's innovations was to describe the crystalline lens as being located in the exact center of the eye.[2] ... the crystalline lens in the center of the eye". Clinical Ophthalmology. 2016 (10): 649-662.. ... led to much discussion in 16th century Europe over whether the principal organ of sight is the traditional Galenic crystalline ...
The idea of the central crystalline lens was widely believed from Hunayn's period through the late 1500s.[3]He describes the ... Hunayn repeatedly emphasized that he believed the crystalline lens to be in the exact center of the eye. Hunayn may have been ... the crystalline lens in the center of the eye". Clinical Ophthalmology. 2016 (10): 649-662. doi:10.2147/OPTH.S100708. PMC ... The lens, described as white, transparent, and luminous have a composition which lends itself to quickly receive colors. As ...
"The effects of protective eyewear on hair and crystalline lens transparency". Dev Ophthalmol. 35: 93-103. doi:10.1159/000060813 ... Dark lenses do not automatically filter out more harmful UV radiation and blue light than light lenses. Inadequate dark lenses ... resulting in dark or light lenses. The lens color is not a guarantee either. Lenses of various colors can offer sufficient (or ... Lenses can be easily removed and swapped for a different lens, usually of a different color. The purpose is to allow the wearer ...
"Measurement of Crystalline Lens Volume During Accommodation in a Lens Stretcher". Investigative Ophthalmology & Visual Science ... Contrary to initial belief, the hyaloid canal does not facilitate changes in the volume of the lens. The lens volume changes by ... which supplies blood to the developing lens. Once the lens is fully developed the hyaloid artery retracts and the hyaloid canal ... Furthermore, lymph, being liquid, is incompressible, so even if the volume of the lens did change, the hyaloid canal could not ...
Hunain repeatedly emphasized that he believed the crystalline lens to be in the center of the eye. Hunain may have been the ... The idea of the central crystalline lens was widely believed from Hunain's period through the late 1500s. He discusses the ... the crystalline lens in the center of the eye". Clinical Ophthalmology. 2016 (10): 649-662. doi:10.2147/OPTH.S100708. PMC ...
Glasser, Adrian; Campbell, Melanie C.W. (January 1998). "Presbyopia and the optical changes in the human crystalline lens with ...
Leffler CT, Hadi TM, Udupa A, Schwartz SG, Schwartz D (2016). "A medieval fallacy: the crystalline lens in the center of the ... Galen actually understood that the crystalline lens is located in the anterior aspect of the human eye. At first reluctantly ... Although many 20th century historians have claimed that Galen believed the lens to be in the exact center of the eye, ... So strong was Galenism that other authors such as Hippocrates began to be seen through a Galenic lens, while his opponents ...
Leffler CT, Hadi TM, Udupa A, Schwartz SG, Schwartz D (2016). "A medieval fallacy: the crystalline lens in the center of the ... During the twentieth century, many historians claimed that Celsus believed that the crystalline lens is in the exact center of ... In fact, Celsus made no specific statement about the position of the crystalline lens, and his Graeco-Roman contemporaries did ... understand that the lens is located to the front. Hippocrates used the Greek word καρκίνος - karkínos, meaning crab or crayfish ...
Hunayn ibn Ishaq, and others beginning with the medieval Arabic period, taught that the crystalline lens is in the exact center ... ISBN 0-226-48233-2. Leffler CT, Hadi TM, Udupa A, Schwartz SG, Schwartz D (2016). "A medieval fallacy: the crystalline lens in ... Rufus was the first to recognise a two-chambered eye, with one chamber from cornea to lens (filled with water), the other from ... The two chambers were seen to hold the same fluid, as well as the lens being attached to the choroid. Galen continued the ...
She moved to Royal Holloway, University of London for her doctorate, completing her thesis on electrostatic electron lenses in ... She develops fast, non-destructive characterisation techniques to study crystalline materials. In particular, Trager-Cowan ... Trager, Carol (1987). The study of novel electrostatic electron lenses (PDF). core.ac.uk (PhD thesis). Royal Holloway, ... 1987 supervised by Doug Heddle [Wikidata]. She completed experimental and theoretical investigations into electrostatic lenses ...
The material is a new crystalline phase of ice, joining 17 others. The research derived from the earlier discovery that water ... Snow Snowflake Ice spike Ice lens Visconti, Guido (2001). Fundamentals of Physics and Chemistry of the Atmosphere. Berlin: ... Temperature and humidity determine many different crystalline forms. Ice crystals are responsible for various atmospheric ...
The species lacks a crystalline eye lens and has evolved a flat cornea. The combination of these traits makes the eye incapable ... Although its eye lacks a lens (this species is also referred to as the "blind dolphin"), the dolphin still uses its eye to ...
They form photosensitizers in the crystalline lens, which has implications for cataract development. Reduced muscle function is ... lens and renal cortex of diabetic rats. The inhibition of AGE formation reduced the extent of nephropathy in diabetic rats. ... "Advanced Glycation Endproducts Induce Photocrosslinking and Oxidation of Bovine Lens Proteins Through Type-I Mechanism". ...
A similar situation arises when areas behind the crystalline lens are to be observed. In this case the observation beam must ... natural crystalline lens, and cornea. The binocular slit-lamp examination provides a stereoscopic magnified view of the eye ... A second, hand-held lens is used to examine the retina. Two conflicting trends emerged in the development of the slit lamp. One ... The use of auxiliary optics - generally as a lens - makes it possible however to bring the far point within the focusing range ...
A cataract is an opacity that develops in the crystalline lens of the eye. The word cataract literally means, "curtain of water ... For instance, when rabbit lenses are placed in high-galactose mediums, a nearly 40% reduction in lens amino acid levels is ... As it turns out, the lens is a favorable site for galactose accumulation. The lens phosphorylates galactose at a relatively ... Thus, the sugar alcohol idly begins to accumulate in the lens. As galactitol concentration increases in the lens, a hypertonic ...
Aging of the crystalline lens of the human eye causes straylight to become worse. Lens extraction and artificial lens ... Contact lenses. Vos JJ. "Disability glare - a state of the art report". Commission International de l'Eclairage Journal. 1984;3 ... "Straylight effects with aging and lens extraction". Am J Ophthalmol. 2007;144:358-363 Van der Meulen IJ et al. "Quality of ... "Straylight measurement in contact lens wear". Cornea 2010;29:516-522. ...
It is present in the cornea and lens of the eye in crystalline form. It may be one of the most abundant proteins in the fossil ... Jesior, J. C.; Miller, A. & Berthet-Colominas, C. (1980). "Crystalline three-dimensional packing is general characteristic of ... they are so well ordered as to be crystalline. A distinctive feature of collagen is the regular arrangement of amino acids in ...
Some proteins naturally form crystalline arrays, like aquaporin in the lens of the eye. In the process of protein ... In 1840, Friedrich Ludwig Hünefeld accidentally discovered the formation of crystalline material in samples of the earthworm ...
The lens is biconvex, and the body of the stemma has a vitreous or crystalline core. ... The eyes of humans and large animals, and camera lenses are classed as "simple" because in both cases a single lens collects ... A dorsal ocellus consists of a lens element (cornea) and a layer of photoreceptors (rod cells). The ocellar lens may be ... Blest, AD; Land (1997). "The Physiological optics of Dinopis Subrufus L.Koch: a fisheye lens in a spider". Proceedings of the ...
The cornea, humours, and crystalline lens of the eye together form a lens that focuses images on the retina. The human eye is ... This convex lens gives the name to the fisheye lens in photography. By wearing a flat diving mask, humans can see clearly ... Corrective lenses are ground flat on one side and optically cemented to the inside face of the mask lens. This provides the ... Bifocal lenses are also available for this application. Some masks are made with removable lenses, and a range of standard ...
If one medium has a particular curved shape, it functions as a lens. The cornea, humours, and crystalline lens of the eye ... Corrective lenses can be fitted to the inside surface of the viewport or contact lenses may be worn inside the mask to allow ... Corrective lenses are ground flat on one side and optically cemented to the inside face of the mask lens. This provides the ... Should a puck hit the lens of a single-lens mask there is a good chance it will break the glass and pass through the aperture ...
... and the crystalline lens 20 diopters. When a cataract is removed, the lens is replaced by an artificial lens implant. By ... The most common use of the A-scan is to determine eye length for calculation of intraocular lens power. Briefly, the total ... a simple formula can be used to calculate the power of the intraocular lens needed. There are several different formulas that ...
"Radiocarbon Dating of the Human Eye Lens Crystallines Reveal Proteins without Carbon Turnover throughout Life". PLoS ONE. 3 (1 ... or the carbon-14 concentration in the lens of the eye. In 2019, Scientific American reported that carbon-14 from nuclear bomb ...
"Radiocarbon Dating of the Human Eye Lens Crystallines Reveal Proteins without Carbon Turnover throughout Life". PLoS ONE. 3 (1 ... The anatomy of the human eye makes desquamation of the lens impossible. Desquamative gingivitis Moist desquamation Pityriasis- ...
... crystalline benzyl penicillin ... Lens. *Cataract *Congenital cataract. *Childhood cataract. * ...
Roshdi Rashed (1990), "A Pioneer in Anaclastics: Ibn Sahl on Burning Mirrors and Lenses", Isis 81 (3), p. 464-491 [464-468]. ... "Decagonal and Quasi-crystalline Tilings in Medieval Islamic Architecture" (PDF). Science. 315: 1106-1110. doi:10.1126/science. ...
276 The crystalline lens of the human eye is an example of a GRIN lens with a refractive index varying from about 1.406 in the ... A gradient-index lens with a parabolic variation of refractive index (n) with radial distance (x). The lens focuses light in ... It determines the focusing power of lenses, the dispersive power of prisms, the reflectivity of lens coatings, and the light- ... The focal length of a lens is determined by its refractive index n and the radii of curvature R1 and R2 of its surfaces. The ...
Cataracts: is the congenital and pediatric pathology that describes the greying or opacity of the crystalline lens, which is ... Legally blind indicates that a person has less than 20/200 vision in the better eye after best correction (contact lenses or ... The definition of visual impairment is reduced vision not corrected by glasses or contact lenses. The World Health Organization ... Some also include those who have a decreased ability to see because they do not have access to glasses or contact lenses.[1] ...
রাতকানার প্রধান কারণ রেটিনাইটিস পিগমেনটোসা নামক একটি রোগ, যার ফলে রেটিনার রড কোষ ধীরে ধীরে আলোর প্রতি সাড়া দেওয়ার সক্ষমতা হারিয়ে ফেলে। এটা একধরনের জেনেটিক রোগ যেখানে রাত্রিকালীন দৃষ্টির পাশাপাশি দিনের বেলা দেখার ক্ষমতাও নষ্ট হতে থাকে। রাত্রিকালীন অন্ধত্বের ফলে জন্ম থেকে রড কোষ জন্মের পর থেকেই কাজ করে না, বা অল্প পরিমাণ কাহ করে, কিন্তু এই অবস্থা আরও খারাপ হতে থাকে।. রাতকানা ...
It is a reddish crystalline solid. It only dissolves a little in water. The hydrate (type with water molecules attached) can ... It is used in lenses. Related pages[change , change source]. *Cobalt(II) hydroxide ...
... can also have a crystalline appearance.. There are over 20 corneal dystrophies that affect all parts of the ...
Crystalline silicon[edit]. Main article: Crystalline silicon. By far, the most prevalent bulk material for solar cells is ... The system also includes an array of fixed lenses/mirrors to concentrate light onto the adaptive surface. As the day continues ... Crystalline silicon panels dominate worldwide markets and are mostly manufactured in China and Taiwan. By late 2011, a drop in ... A conventional crystalline silicon solar cell (as of 2005). Electrical contacts made from busbars (the larger silver-colored ...
... which is caused by the eye's crystalline lens losing elasticity, progressively reducing the ability of the lens to accommodate ... Corrective lenses can be produced in many different shapes from a circular lens called a lens blank. Lens blanks are cut to fit ... "BluTech Lenses - Technology, The story behind BluTech Lenses". BluTech Lenses.. *^ "Expert Healthy Vision & Eye Care Tips, News ... Higher power lenses can cause distortion of peripheral vision and may become thick and heavy if a large lens shape is used. ...
Copper deposition in peripheral Descemet membrane (Kayser-Fleischer ring) and anterior capsule of crystalline lens ( Sunflower ...
People who wear contact lenses and those whose infection is caused by gonorrhea or chlamydia should be treated.[2] Allergic ... from infected eye drops or contact lenses, from the genitals or the bloodstream.[12] Infection by human adenovirus accounts for ... Antibiotics are also recommended for those who wear contact lenses, are immunocompromised, have disease which is thought to be ...
The majority of modules use wafer-based crystalline silicon cells or thin-film cells. The structural (load carrying) member of ... Some special solar PV modules include concentrators in which light is focused by lenses or mirrors onto smaller cells. This ... In 2013, crystalline silicon accounted for more than 90 percent of worldwide PV production, while the rest of the overall ... IEC 61215 (crystalline silicon performance), 61646 (thin film performance) and 61730 (all modules, safety) ...
These make it especially useful for wide-angle camera lenses, microscopy, and the core part of optical fibers.[62][63] It has ... Zone refining techniques have led to the production of crystalline germanium for semiconductors that has an impurity of only ... GeH4 reacts with alkali metals in liquid ammonia to form white crystalline MGeH3 which contain the GeH3− anion.[33] The ... it is an important infrared optical material that can be readily cut and polished into lenses and windows. It is especially ...
High refractive index and alkali-resistant glass, flint, hydrogen storage, battery-electrodes, camera lenses, fluid catalytic ... while HREE may prefer to remain in the crystalline residue, particularly if it contains HREE-compatible minerals like garnet.[ ... and lenses.[24][25] These fluids have very low viscosities and high element mobility, which allows for crystallization of large ... by leaching them out of the crystalline residue. The resultant magma rises as a diapir, or diatreme, along pre-existing ...
"A medieval fallacy: the crystalline lens in the center of the eye". Clinical Ophthalmology. 10 (10): 649-62. 2016. doi:10.2147/ ... "Toric Lens Implants , Pacific Cataract and Laser Institute: For Doctors of Optometry". odpcli.com. ശേഖരിച്ചത് 2019-10-09.. ...
One example is SU8 based lens where SU8 based square blocks are generated. Then the photoresist is melted to form a semi-sphere ... Even though the electronics industry provides an economy of scale for the silicon industry, crystalline silicon is still a ...
... (BCD), also called Bietti crystalline corneoretinal dystrophy,[1] is a rare autosomal recessive[ ... Sahu, DK; Rawoof, AB (2002). "Bietti's crystalline dystrophy". Indian J Ophthalmol. Medknow. 50 (4): 330-332. PMID 12532504.. ... Bietti's crystalline dystrophy has an autosomal recessive pattern of inheritance.. ... "Bietti crystalline corneoretinal dystrophy is caused by mutations in the novel gene CYP4V2". Am. J. Hum. Genet. 74 (5): 817-26 ...
"Radiocarbon Dating of the Human Eye Lens Crystallines Reveal Proteins without Carbon Turnover throughout Life". PLoS ONE. 3 (1 ... or the carbon-14 concentration in the lens of the eye.[32] ...
... photoelectrica" (arc eye) means inflammation caused by photoelectric UV light. It is a type of ultraviolet keratitis. Such UV exposure can be caused by arc welding without wearing protective eye glass, or by high altitude exposure from sunlight reflected from snow ("snow blindness"). The inflammation will only appear after about 6 to 12 hours. It can be treated by rest, as the inflammation usually heals after 24-48 hours. Proper eye protection should be worn to prevent keratoconjunctivitis photoelectrica ...
"Laser Lensing". OpTek Systems Inc.. *^ Atkins, R. M.; Simpkins, P. G.; Yablon, A. D. (2003). "Track of a fiber fuse: a Rayleigh ... Bartenev, G (1968). "The structure and strength of glass fibers". Journal of Non-Crystalline Solids. 1: 69-90. Bibcode:1968JNCS ... the emitted beam has an almost perfect Gaussian shape-even in the far field-if a good lens is used. The lens needs to be large ... Aspheric lenses are typically used.. Fiber fuse[edit]. At high optical intensities, above 2 megawatts per square centimeter, ...
Lenses[edit]. Optometrists can supply colored spectacle lenses or a single red-tint contact lens to wear on the non-dominant ... A 1981 review of various studies to evaluate the effect of the X-chrom contact lens concluded that, while the lens may allow ... Siegel, I. M. (1981). "The X-Chrom lens. On seeing red". Surv Ophthalmol. 25 (5): 312-24. doi:10.1016/S0039-6257(81)80001-X. ... Lenses that filter certain wavelengths of light can allow people with a cone anomaly, but not dichromacy, to see better ...
The Early Development of Electron Lenses and Electron Microscopy. ISBN 3-7776-0364-3. .. ... Crystalline diffraction pattern from a twinned grain of FCC Austenitic steel. അവലംബം[തിരുത്തുക]. *↑ "Viruses". users.rcn.com.. ... "The objective lens of a TEM, the heart of the electron microscope".. ... "The Nobel Prize in Physics 1986, Perspectives - Life through a Lens". nobelprize.org.. ...
There is currently researching being done to find more treatments dependent on the different pre-existing conditions. Studies are being conducted in which madarosis can be related to malignancy. A study by Groehler and Rose found that there was a statistical significance between these two. They concluded that patients malignancy lesions on the eyelid have a higher chance of having madarosis than a patient with a benign lesion. They stated that despite the fact that it is significant, the absence of madarosis does not mean the lesion cannot be malignant.[10] In many leprosy cases, madarosis is a symptom or a quality after diagnosis. However, in India, leprosy is common and researchers report a case of madarosis before diagnosis of leprosy with no skin lesions, only madarosis. This allowed for quicker treatment.[11] A main reason many people have madarosis is due to the chemotherapy drugs. There was a clinical trial in 2011 that tested an eyelash gel called bimatoprost. This gel enhanced the ...
Yellowed thorium dioxide lens (left), a similar lens partially de-yellowed with ultraviolet radiation (centre), and lens ... "Synthesis, structure, and reactivity of crystalline molecular complexes of the {[C5H3(SiMe3)2]3Th}1− anion containing thorium ... Such glass finds application in high-quality lenses for cameras and scientific instruments.[39] The radiation from these lenses ... "Thoriated Camera Lens (ca. 1970s)". Oak Ridge Associated Universities. 1999. Retrieved 29 September 2017.. ...
Furthermore, ΔS will reach zero at zero temperature, but S itself will also reach (0)zero, at least for perfect crystalline ... Gravitational lens. *Bondi accretion. *M-sigma relation. *Quasi-periodic oscillation. *Thermodynamics *Immirzi parameter ...
Crystalline silicon is the predominant material used in 90 percent of worldwide produced solar modules, while rival thin-film ... Concentrator photovoltaics (CPV) and high concentrator photovoltaic (HCPV) systems use optical lenses or curved mirrors to ... Most modules (60 or 72 crystalline silicon cells) generate 160 W to 300 W at 36 volts. It is sometimes necessary or desirable ... In the last 10 years, the efficiency of average commercial wafer-based crystalline silicon modules increased from about 12% to ...
"High-Index Lenses Push Immersion Beyond 32 nm". Archived from the original on 2015-09-29.. ... Zhao, X-A; Kolawa, E; Nicolet, M-A (1986). "Reactions of thin metal films with crystalline and amorphous Al2O3". California ... By setting up multiple lasers and mirrors, the amount of energy loss is minimized, also since the lenses are coated with ... is the numerical aperture of the lens as seen from the wafer ... and the ability of the reduction lens system to capture enough ...
A petrographic microscope - an optical microscope fitted with cross-polarizing lenses, a conoscopic lens, and compensators ( ... which gives information about strain within the crystalline structure of the rocks. They also plot and combine measurements of ... These stretched rocks can also pinch into lenses, known as boudins, after the French word for "sausage" because of their visual ... and interference properties with a conoscopic lens.[28] In the electron microprobe, individual locations are analyzed for their ...
A conduit through which a drug is introduced penetrates at least the outer lens capsule for drug delivery. When withdrawn, the ... A method of delivering a drug or other compound to the lens of the eye. ... A cataract refers to any opacity of the ocular crystalline lens. The normal crystalline lens is transparent, refractive, and ... wherein the conduit penetrates at least one of a lens capsule, a lens subcapsule epithelium, a lens cortex, or a lens nucleus. ...
... of Laser Treatment of the Crystalline Lens in Subjects Having Elected to Undergo Lens Extraction and Intraocular Lens ... Laser Treatment of the Crystalline Lens. The safety and scientific validity of this study is the responsibility of the study ... Lens removal a. Ease of irrigation / aspiration (time) b. Reduced ultrasound phacoemulsification [ Time Frame: Time of surgery ... of this study is to evaluate the feasibility of the LensAR laser system to surgically intervene within the crystalline lens. ...
... Shiels A., Bassnett S., Varadaraj K., Mathias R., ... At 3 wk of age (postnatal day 21), lenses from null mice (Aqp0(-/-)) contained polymorphic opacities, whereas lenses from ... to trigger cataractogenesis in mice and suggest that this MIP is required for optimal focusing of the crystalline lens. ... Aquaporin-0 (AQP0), a water transport channel protein, is the major intrinsic protein (MIP) of lens fiber cell plasma membranes ...
Post-traumatic suprachoroidal dislocation of crystalline lens and its management.. Shanmugam MP1, Shah P1, Rajesh R1, Mishra DK ... Post-traumatic suprachoroidal dislocation of crystalline lens and its management. Indian J Ophthalmol. 2019 Sep;67(9):1469-1470 ... intraoperative view of taut separated choroid and the lens lying in the suprachoroidal space, and (d) residual lens in ... pictorial representation of suprachoroidal dislocated lens, (c) ...
Crystalline" by people in Harvard Catalyst Profiles by year, and whether "Lens Cortex, Crystalline" was a major or minor topic ... "Lens Cortex, Crystalline" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, MeSH (Medical ... The portion of the crystalline lens surrounding the nucleus and bound anteriorly by the epithelium and posteriorly by the ... Greiner JV, Auerbach DB, Leahy CD, Glonek T. Distribution of membrane phospholipids in the crystalline lens. Invest Ophthalmol ...
Expression pattern of AP-1 proto-oncogenes during morphogenesis and wound repair of the crystalline lens. ... Changes of the Corneal Thickness, Anterior Chamber Depth and Human Crystalline Lens Thickness during Accommodation, Observed by ... Problem in Quantitalive Evaluation of Posterior Capsular Opacification Using the Crystalline Lens Image Analysis Method. ... Sample records for lens crystalline. from WorldWideScience.org. Sample records 1 - 20 shown. Select sample records: 1 - 20. 21 ...
... lens higher order aberrations (HOAs) were calculated as the whole eye minus the corneal aberrations. Visual simulation using ... To evaluate the impact of the lens aberrations on the adaptive optics visual simulation of pseudophakic intraocular lens (IOL) ... crystalline lens, and induced profile of the simulated IOL, but after surgery the lens will not be present. Lens aberrations ... Effect of Crystalline Lens Aberrations on Adaptive Optics Simulation of Intraocular Lenses. Eloy A. Villegas, PhD; Silvestre ...
Crystalline Lens and Cataract by Joah F. Aliancy and Nick Mamalis. Crystalline Lens and Cataract ... Figure 3. Layers of the lens. Upper section is through the anterior lens capsule showing lens epithelial cells, lec, and lens ... Crystalline Lens and Cataract by Joah F. Aliancy and Nick Mamalis. *Intraocular Lenses for Cataract Surgery by Jason Nguyen and ... HISTOLOGY OF THE LENS. Figure 3 shows a stained section of the adult human lens with anterior part of the lens in the top ...
Anterior displacement of the unstable lens may play a role in the high IOP, and removal of the crystalline lens is often ... Phacodonesis and a Subluxated Crystalline Lens. Ehud I. Assia, MD; Steven Dewey, MD; Richard J. Mackool, MD; Mark Packer, MD; ... crstoday.com/articles/2010-mar/complex-case-management-phacodonesis-and-a-subluxated-crystalline-lens/ ... crstoday.com/articles/2010-mar/complex-case-management-phacodonesis-and-a-subluxated-crystalline-lens/ ...
The cornea has greater refractive power which is static, but the lens is a unique biological structure that relies on... ... The refracting power of the human eye is contributed by the cornea and the lens. ... Posterior Capsule Lens Epithelial Cell Chromatic Aberration Lens Capsule Lens Fiber These keywords were added by machine and ... Kasturi N., Matalia J. (2017) Anatomy of the Human Crystalline Lens. In: Chakrabarti A. (eds) Posterior Capsular Rent. Springer ...
Crystalline lens change peculiar to diabetes Hiroshi Sasaki; Natsuko Hatsusaka; Hisanori Miyashita; Naoko Shibata; Yusuke Seki ... Crystalline lens change peculiar to diabetes You will receive an email whenever this article is corrected, updated, or cited in ... Purpose : We investigated the relationship among diabetes mellitus (DM), diabetic retinopathy (DMR) and crystalline lens ... Crystalline lens change peculiar to diabetes. Invest. Ophthalmol. Vis. Sci. 2017;58(8):3642. ...
Although the increment of pupil size increases the probability of patients with significant visual impact of lens HOAs, the ... The effect of lens aberrations on visual simulation is imperceptible for a small pupil diameter of 3 mm. ... Effect of Crystalline Lens Aberrations on Adaptive Optics Simulation of Intraocular Lenses J Refract Surg. 2019 Feb 1;35(2):126 ... no lens-HOA), removing spherical aberration (no lens-SA), and with lens HOA (natural condition). In addition, a through-focus ...
Comparison of Scheimpflug Photos of the Crystalline Lens in Patients Who Have Undergone Vitrectomy Surgery and Controls. The ... Scheimpflug crystalline lens photographs will be taken for evaluation of level and progression of cataract development.. ... Comparison of Scheimpflug Photos of the Crystalline Lens in Patients Who Have Undergone Vitrectomy Surgery and Controls. ... Comparison of Scheimpflug Photos of the Crystalline Lens in Patients Who Have Undergone Vitrectony Surgery and Controls. ...
The 14C content of the lens proteins thus reflects the atmospheric content of 14C when the lens crystallines were formed. ... due to lens accommodation, yet its most important constituent, the lens crystalline, is never subject to turnover or ... Precise radiocarbon dating is made possible by comparing the 14C content of the lens crystallines to the so-called bomb pulse, ... Because the epithelial basement membrane (lens capsule) completely encloses the lens, desquamation of aging cells is impossible ...
Internal Crystalline Lens Structure Imaging using Long Range Optical Coherence Tomography Carolina P. de Freitas; Marco Ruggeri ... Internal Crystalline Lens Structure Imaging using Long Range Optical Coherence Tomography You will receive an email whenever ... Purpose: : To demonstrate the feasibility of quantifying the internal human crystalline lens structure using Optical Coherence ... Results: : The lens structure is apparent in all isolated and in vivo lenses. The number of discrete zones of optical ...
P. Rosales, M. Wendt, S. Marcos, and A. Glasser, "Changes in crystalline lens radii of curvature and lens tilt and decentration ... P. Rosales, M. Wendt, S. Marcos, and A. Glasser, "Changes in crystalline lens radii of curvature and lens tilt and decentration ... P. Rosales, M. Wendt, S. Marcos, and A. Glasser, "Changes in crystalline lens radii of curvature and lens tilt and decentration ... P. Rosales, M. Wendt, S. Marcos, and A. Glasser, "Changes in crystalline lens radii of curvature and lens tilt and decentration ...
Over 69 Crystalline lens pictures to choose from, with no signup needed. Download in under 30 seconds. ... A cataract is an clouding crystalline lens inside the eye. Clipart Vectorby slobodyan_780/0. Human Eye Cross Section Vectors ...
The effect of optical self-adjustment in the linear eyeball model with the crystalline lens and without lens Author(s): W. ... Subsequently, the results of investigations carried out on the model with and without eye lens are compared. ... passive non-accommodating eye lens. We look for such conditions, that placed upon geometry and material parameters of the ...
The crystalline lens stopped thinning, flattening, and losing power within ±1 year of onset in children who became myopic ... Corneal and crystalline lens parameters in children who became myopic were compared with age-, gender-, and ethnicity-matched ... Before myopia onset, the crystalline lens thinned, flattened, and lost power at similar rates for emmetropes and children who ... Myopia onset is characterized by an abrupt loss of compensatory changes in the crystalline lens that continue in emmetropes ...
Measurement of vibrations induced on the surface of crystalline eye lens using PhS-SDOCT Author(s): Narendran Sudheendran; ... The results indicate that the system could detect vibrations as small as 0.45 μm induced on the surface of crystalline lens, ... Experimental assessment of stiffness of crystalline lens of the eye can help in understanding several ocular diseases. Studies ... and hence, PhS-SDOCT could be potentially used to assess stiffness of a crystalline lens. ...
H. A. Weeber, G. Eckert, W. Pechhold, and R. G. van der Heijde, "Stiffness gradient in the crystalline lens," Graefes Arch. ... G. Scarcelli, P. Kim, and S. H. Yun, "In vivo measurement of age-related stiffening in the crystalline lens by Brillouin ... G. Scarcelli, P. Kim, and S. H. Yun, "In vivo measurement of age-related stiffening in the crystalline lens by Brillouin ... H. A. Weeber, G. Eckert, W. Pechhold, and R. G. van der Heijde, "Stiffness gradient in the crystalline lens," Graefes Arch. ...
Actin and myosin within the crystalline lens maintain the structural integrity of lens fiber cells and form a hexagonal lattice ... Effects of a myosin light chain kinase inhibitor on the optics and accommodation of the avian crystalline lens. ... Effects of a myosin light chain kinase inhibitor on the optics and accommodation of the avian crystalline lens. UWSpace. http ... cradling the posterior surface of the lens. The actomyosin network was pharmacologically disrupted to examine the effects on ...
According to homeopathic principles the ingredients of Natural Ophthalmics Cataract Pellets may help to benefit the crystalline ... Natural Ophthalmics Cataract Crystalline Lens Eye Drops, 15 ml. Our Price: $17.64 ... Nourishes and detoxifies the living tissue of the crystalline lens. *Cineraria maritima has been used homeopathically for over ... and nutrients from the blood to the aqueous which both nourishes and detoxifies the living tissue of the crystalline lens. ...
lens fibres, which make up most of the lens.. For the lens to work, the ciliary muscles change the shape of the lens which ... The crystalline lens, or lens, is a bi-convex structure in the eye that is transparent and which works with the cornea to ... lens capsule, which forms the outermost layer;. *lens epithelium, which sits between the lens capsule and the outermost layer ... How does the crystalline lens work?. The amount of light entering the eye is controlled by the iris, which sits in front of the ...
Frost, N. A., Sparrow, J. M. and Moore, L. (2002) Associations of human crystalline lens retrodots and waterclefts with visual ... Associations of human crystalline lens retrodots and waterclefts with visual impairment: an observational study ... and 11 clinicopathologic classes of opacity in the human crystalline lens. Methods: The Somerset and Avon Eye Study is an ... The associations of lens features (posterior subcapsular cataract, nuclear color, nuclear white scatter, cortical spokes, ...
Volumetric macro- and micro-scale assessment of crystalline lens opacities in cataract patients using long-depth-range swept ... The instrument might be a useful tool in the highresolution preoperative evaluation of crystalline lens opacities in cataract ... We demonstrate an optimized optical platform for the three-dimensional (3-D) visualization of crystalline lens opacities in ... The results showed lens micro- and macro-scale features related to possible cataract development such as cortical spokes, water ...
I am a board-certified ophthalmologist interested in asp.net, visual basic and Xcode programming. I have posted some visual studio programs below to the left to help with common calculations. I occasionally post photos and clinical scenarios from my clinical practice. Aaron Sobol
Crystalline. On-line free medical diagnosis assistant. Ranked list of possible diseases from either several symptoms or a full ... Lens Capsule, Crystalline. The thin noncellular outer covering of the CRYSTALLINE LENS composed mainly of collagen type iv and ...
crystalline lens. Lens. What is the Crystalline Lens?. The crystalline lens is a transparent structure of the eye filled with ... Why does the crystalline lens change shape?. Unlike the cornea that has a fixed shape, the lens changes shape to enable the eye ... Where is the crystalline lens located?. The lens is located behind the iris and in front of the vitreous body. ... Common Conditions of the Lens. As we age lens fibers grow denser and less elastic. The lens becomes stiff making it more ...
  • Accommodation in the human eye occurs through controlled changes in crystalline lens shape, thickness, and refractive surface placement relative to the cornea. (google.com.au)
  • The lens of the eye is a biconvex, relatively acellular, optically transparent intraocular structure that with the cornea serves to transmit light to the retina with minimal light scattering (Fig. 1a). (utah.edu)
  • Notice the lens is flatter anteriorally, facing the cornea (cornea). (utah.edu)
  • The refracting power of the human eye is contributed by the cornea and the lens. (springer.com)
  • The cornea has greater refractive power which is static, but the lens is a unique biological structure that relies on an extraordinarily intricate arrangement of highly specialized cells to produce a gradient of refractive index that allows for remarkable dynamic focusing of an image with minimal spherical or chromatic aberration [1]. (springer.com)
  • The crystalline lens , or lens, is a bi-convex structure in the eye that is transparent and which works with the cornea to refract light to focus on the retina. (advancedvisioncare.co.uk)
  • The cornea bends, or refracts, the light and passes it through the pupil to the lens. (everydaysight.com)
  • Unlike the cornea that has a fixed shape, the lens changes shape to enable the eye to focus at various distances. (everydaysight.com)
  • Together with the lens, the cornea bends (refracts) light to focus it onto the back of your eye. (hoyavision.com)
  • Much like a camera lens, the cornea helps to focus light coming into the eye onto the retina. (verywellhealth.com)
  • The iris also acts as a wall that separates the anterior chamber (between cornea and iris) from the posterior chamber (between the iris and crystalline lens). (lenstore.co.uk)
  • 2001). Fourier and power law analysis of structural complexity in cornea and lens. (core.ac.uk)
  • 1998). Gene sharing in lens and cornea: facts and implications. (core.ac.uk)
  • Other techniques, such as MRI and the Scheimpflug technique, which uses a camera perpendicular to a slit beam to create a section of the cornea and lens, have broader applications. (photonics.com)
  • The cornea and the crystalline lens are both important for the eye to focus light. (sciencelearn.org.nz)
  • 4 . The foldable intraocular lens of claim 1 wherein said lens is a phakic refractive lens structurally adapted for positioning either in the anterior chamber, in the posterior chamber, or within the cornea. (google.co.uk)
  • The lens is a transparent biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina. (wikipedia.org)
  • An irregular shape to the cornea causes this common refractive error that can usually be corrected with glasses or contact lenses. (avesis.com)
  • The clear human lens inside the eye, that along with the cornea, focuses light onto the retina to create a clear image. (avesis.com)
  • All ocular tissues contain taurine, and quantitative analysis of ocular tissue extracts of the rat eye revealed that taurine was the most abundant amino acid in the retina, vitreous, lens, cornea, iris, and ciliary body. (biomedsearch.com)
  • The cornea refracts light before the crystalline lens do. (everything2.com)
  • The normal crystalline lens is transparent, refractive, and provides adequate accommodation (shape change) to transmit and focus light on the retina at various distances. (google.com.au)
  • We now know that this is the function of the retina, with the lens serving as a conduit of light transmission and focus to the retina. (utah.edu)
  • The lens can change shape with the aid of the ciliary muscles, thereby changing the focal distance to the retina and bringing the image into sharp focus on the retina. (utah.edu)
  • A human eyeball cut in half to show the lens and the passage of light through it from the object ahead to the focus on the retina. (utah.edu)
  • By changing shape, the lens bends, or refracts light onto the retina to create clear images of objects positioned at various distances. (everydaysight.com)
  • The lens changes shape to continue bending the rays and focuses the light onto the retina. (everydaysight.com)
  • As light passes through the cloudy lens it cannot focus clearly on the retina and creates a hazy or blurry picture. (everydaysight.com)
  • In farsightedness ( hyperopia ) the image is focused behind the retina because the refractive power of the lens is too weak or the eyeball axis is too short. (thefreedictionary.com)
  • Nearsightedness ( myopia ) occurs when the refractive power of the lens is too strong or the eyeball is too long, so that the image is focused in front of the retina. (thefreedictionary.com)
  • The eye's lens collects the light entering the pupil, thus ensuring a sharp image on the retina. (zeiss.com)
  • The lens turns the image we see on its head and visualizes it on the retina back to front. (zeiss.com)
  • The crystalline lens is a transparent structure in the eye-suspended immediately behind the iris-that brings rays of light to a focus on the retina. (verywellhealth.com)
  • the crystalline lens is an ocular component of high transparency and refractive index that is responsible for variable focusing of light rays onto the photosensitive retina. (physiology.org)
  • They are composed of long tubes connecting bifocal lenses with two retinas: a distal retina situated a few hundred micrometers behind the lens, and a proximal retina that is situated directly beneath. (biologists.org)
  • His work led to much discussion in 16th century Europe over whether the principal organ of sight is the traditional Galenic crystalline humour or the Averroist aranea , which in turn led to the discovery that the retina is the principal organ of sight. (wikipedia.org)
  • The lens, by changing shape, functions to change the focal distance of the eye so that it can focus on objects at various distances, thus allowing a sharp real image of the object of interest to be formed on the retina. (newworldencyclopedia.org)
  • A conduit through which a drug is introduced penetrates at least the outer lens capsule for drug delivery. (google.com.au)
  • 1 . An ocular drug delivery method comprising penetrating at least an outer capsule of an ocular lens with a conduit to create an aperture in the lens and introducing a drug into the lens through the aperture, wherein the aperture is self-sealing upon removal of the conduit. (google.com.au)
  • 11 . The method of claim 1 wherein the conduit penetrates at least one of a lens capsule, a lens subcapsule epithelium, a lens cortex, or a lens nucleus. (google.com.au)
  • 12 . The method of claim 1 wherein the conduit penetrates an anterior lens capsule or a posterior lens capsule. (google.com.au)
  • 14 . A localized ocular drug delivery method comprising penetrating at least an outer capsule of an ocular lens with a conduit to create an aperture, providing an agent directly into the lens via the conduit through the aperture, and withdrawing the conduit wherein the agent is substantially confined within the lens. (google.com.au)
  • Cataracts are most frequently associated with the normal aging process or pathology, but injury or mechanical violation of the ocular capsule surrounding the lens also causes cataract formation. (google.com.au)
  • Because of the risk of inducing cataract formation, penetrating the lens capsule to introduce drugs or other agents into the lens has not been favorably considered. (google.com.au)
  • One embodiment of the invention is an ocular drug delivery method by penetrating at least the outer capsule of the lens with a fine conduit that creates a self-sealing aperture when it is removed, then introducing a drug into the lens through this aperture. (google.com.au)
  • The portion of the crystalline lens surrounding the nucleus and bound anteriorly by the epithelium and posteriorly by the capsule. (harvard.edu)
  • This basement membrane will eventually form the lens capsule. (utah.edu)
  • Upper section is through the anterior lens capsule showing lens epithelial cells, lec, and lens fibers, lf. (utah.edu)
  • Lower section is of the posterior lens capsule, plc and cortical fibers (cf). (utah.edu)
  • The lens is composed of 4 structures: capsule, epithelium, cortex and nucleus (Fig. 3). (utah.edu)
  • My preference, however, would be to preserve the posterior capsule by fixating the lens capsule to the scleral wall. (crstoday.com)
  • capsule of lens the elastic sac enclosing the lens of the eye. (thefreedictionary.com)
  • The rests of a forward capsule were densely connected with a back capsule of a crystalline lens. (escrs.org)
  • The technics of operation consisted in formation in the centre of a back capsule of a crystalline lens of an aperture, diameter 4,0-4,5 mm through paracentesis with a tip of vitractor 25-gauge. (escrs.org)
  • The method of klipping deployed IOL on a back capsule of a crystalline lens allows to reach good and stable centration of deployed IOL. (escrs.org)
  • Furthermore, the protein collectively on the basal membrane complicated SEMA3A (BMC) from the posterior zoom lens surface area have been proven to mediate fibers cell migration across, and anchor fibers cells to, the zoom lens capsule 1092788-83-4 supplier [15]. (conferencedequebec.org)
  • The lens has three main parts: the lens capsule, the lens epithelium, and the lens fibers. (wikipedia.org)
  • The lens capsule forms the outermost layer of the lens and the lens fibers form the bulk of the interior of the lens. (wikipedia.org)
  • The cells of the lens epithelium, located between the lens capsule and the outermost layer of lens fibers, are found only on the anterior side of the lens. (wikipedia.org)
  • The lens capsule is a smooth, transparent basement membrane that completely surrounds the lens. (wikipedia.org)
  • The capsule is very elastic and so allows the lens to assume a more globular shape when not under the tension of the zonular fibers (also called suspensory ligaments), which connect the lens capsule to the ciliary body. (wikipedia.org)
  • The lens epithelium, located in the anterior portion of the lens between the lens capsule and the lens fibers, is a simple cuboidal epithelium. (wikipedia.org)
  • Intraocular lenses containing a photochromic agent having its maximum absorption peak in the wavelength range of about 400-500 nm, are disclosed. (google.co.uk)
  • Methods for making these intraocular lenses are also taught. (google.co.uk)
  • New high refractive index polymeric compositions and foldable intraocular lenses made from such compositions are disclosed. (google.co.uk)
  • Hydrolytically degradable multilayer films were used to create a multi-drug delivery coating for intraocular lenses (IOL). (mit.edu)
  • The establishment of a drug delivery coating for intraocular lenses required key advances in ultrathin film technology. (mit.edu)
  • The power, versatility, and utility of this multi-functional system were highlighted by the creation of functional drug coatings on intraocular lenses, bandage, and sutures. (mit.edu)
  • Combined, these efforts surmounted key challenges toward the development of intraocular lenses able to prevent complications of cataract surgery and enhanced the fundamental understanding of layer-by-layer systems. (mit.edu)
  • Finally the lens is pinched off and settles in place with the developing iris and ciliary body in the front of the eyeball (3). (utah.edu)
  • The amount of light entering the eye is controlled by the iris, which sits in front of the lens. (advancedvisioncare.co.uk)
  • The lens is located behind the iris and in front of the vitreous body. (everydaysight.com)
  • In front of the lens is the iris, which regulates the amount of light entering into the eye. (wikipedia.org)
  • Anterior to the lens is the iris, which regulates the amount of light entering the eye. (newworldencyclopedia.org)
  • We report a patient who underwent pars plana vitrectomy for a giant tear after receiving blunt trauma to his right eye and sustained postoperative perfluorocarbon liquid residue in the anterior chamber in spite of an intact crystalline lens. (biomedcentral.com)
  • He underwent a three-port pars plana vitrectomy for the giant tear without crystalline lens extraction. (biomedcentral.com)
  • A 48-year-old female presented with traumatic posterior subluxated crystalline lens and underwent combined 23-gauge pars plana vitrectomy (PPV) and lensectomy. (escrs.org)
  • Post-traumatic suprachoroidal dislocation of crystalline lens and its management. (nih.gov)
  • Trauma to the eye can cause subluxation, or dislocation of the lens. (everydaysight.com)
  • Three weeks after the surgery, a residue of heavy liquid was observed in the anterior chamber, even though the patient had an intact crystalline lens without any tilt or dislocation. (biomedcentral.com)
  • No tilt or dislocation of the crystalline lens was detected on slit lamp biomicroscopy. (biomedcentral.com)
  • This work aims to report three different surgical techniques for removal of retained lens fragments secondary to spontaneous dislocation or complicated cataract extraction. (escrs.org)
  • In the second case, a 81 year-old-male with pseudoexfoliation syndrome presented with sudden monocular loss of visual acuity (VA) and has been diagnosed completely posterior dislocation of the total crystalline lens. (escrs.org)
  • Lens dislocation, abnormal position of the crystalline lens of the eye. (britannica.com)
  • Subjects with anterior segment pathology in the eye to be treated that is not directly improved by lens extraction and IOL implantation. (clinicaltrials.gov)
  • The lens is more flat on its anterior side than on its posterior side. (utah.edu)
  • The anterior cells become the lens epithelial cells, while the primary lens fibers collectively form the embryonic nucleus. (utah.edu)
  • Figure 3 shows a stained section of the adult human lens with anterior part of the lens in the top section and the posterior part in the lower section. (utah.edu)
  • Anterior displacement of the unstable lens may play a role in the high IOP, and removal of the crystalline lens is often associated with decreased pressure. (crstoday.com)
  • I have developed with Hanita Lenses (Kibbutz Hanita, Israel) an alternative device, the AssiAnchor (not available in the United States), which clips to the anterior capsuleand is sutured to the scleral wall 1,2 (Figure 3). (crstoday.com)
  • For isolated lenses thicknesses ranged from 0.88-1.67mm for the anterior cortex, 0.72-1.17mm for the posterior cortex and 2.27-2.83mm for the nucleus. (arvojournals.org)
  • Custom Spectral Domain Optical Coherence Tomography (SD-OCT) provided with automatic quantification and distortion correction algorithms was used to measure anterior and posterior crystalline lens surface elevation in accommodating eyes and to evaluate relationships between anterior segment surfaces. (osapublishing.org)
  • Anterior and posterior lens radii of curvature decreased at a rate of 0.78 ± 0.18 and 0.13 ± 0.07 mm/D, anterior chamber depth decreased at 0.04 ± 0.01 mm/D and lens thickness increased at 0.04 ± 0.01 mm/D with accommodation. (osapublishing.org)
  • Anterior bulging of the crystalline lens and the presence of fluid pockets on OCT images of the anterior segment are suggestive of an intumescent cataract. (symptoma.com)
  • Presence of heavy liquids in the anterior chamber may be associated with zonular defects even though the patient has an intact crystalline lens. (biomedcentral.com)
  • Colour images of perfluorodecalin residue in anterior chamber of a 17-year-old male with an intact crystalline lens. (biomedcentral.com)
  • It lies in front of the crystalline lens and separates the anterior chamber from the posterior chamber. (verywellhealth.com)
  • In squirrels, rabbits, and human beings, f-actin is organized in polygonal arrays on the anterior encounters of crystalline lens and is connected with myosin inside the epithelium [14]. (conferencedequebec.org)
  • The actomyosin complicated on the anterior epithelium continues to be speculated to facilitate lodging by enabling the epithelial cells to improve form or by permitting the zoom lens all together to change right into a even more spherical form [16]. (conferencedequebec.org)
  • The lens is part of the anterior segment of the human eye. (wikipedia.org)
  • Posterior to the lens is the vitreous body, which, along with the aqueous humor on the anterior surface, bathes the lens. (wikipedia.org)
  • The lens fibers stretch lengthwise from the posterior to the anterior poles and, when cut horizontally, are arranged in concentric layers rather like the layers of an onion. (wikipedia.org)
  • The anterior monolayer of epithelial cells retains lifelong mitotic capacity and, subsequently, the lens continues to grow by laying down concentric shells of secondary fibers that elongate from epithelial cells within the germative zone at the lens equator. (physiology.org)
  • Histological section of normal crystalline lens (H&E stain, X2). (utah.edu)
  • Lens Cortex, Crystalline" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (harvard.edu)
  • This graph shows the total number of publications written about "Lens Cortex, Crystalline" by people in Harvard Catalyst Profiles by year, and whether "Lens Cortex, Crystalline" was a major or minor topic of these publication. (harvard.edu)
  • Below are the most recent publications written about "Lens Cortex, Crystalline" by people in Profiles. (harvard.edu)
  • The secondary lens fibers eventually grow to form the adult nucleus with new layers of lens fibers forming the lenticular cortex. (utah.edu)
  • Moving outwards from the central, oldest layer, the lens is split into an embryonic nucleus, the fetal nucleus, the adult nucleus, and the outer cortex. (wikipedia.org)
  • New lens fibers, generated from the lens epithelium, are added to the outer cortex. (wikipedia.org)
  • Lens vesicle posterior epithelial cells (pec) elongate to form the primary lens fibers (H&E stain, X10). (utah.edu)
  • Subsequently, secondary lens fibers begin to elongate from the lens epithelial cells to form the fetal nucleus during the gestation period and continues to grow multiple layers. (utah.edu)
  • Much like additional epithelial cells in the torso, zoom lens epithelial cells consist of cytoskeletal filaments, the tiniest which are referred to as microfilaments and so are found through the entire zoom lens [7]. (conferencedequebec.org)
  • As ions, nutrients, and liquid enter the lens from the aqueous humor, Na+/K+-ATPase pumps in the lens epithelial cells pump ions out of the lens to maintain appropriate lens osmotic concentration and volume, with equatorially positioned lens epithelium cells contributing most to this current. (wikipedia.org)
  • In 20 right phakic eyes, lens higher order aberrations (HOAs) were calculated as the whole eye minus the corneal aberrations. (healio.com)
  • To describe corneal and crystalline lens dimensions before, during, and after myopia onset compared with age-matched emmetropic values. (ovid.com)
  • Refractive error was measured using cycloplegic autorefraction, corneal power using a hand-held autokeratometer, crystalline lens parameters using video-based phakometry, and vitreous chamber depth (VCD) using A-scan ultrasonography. (ovid.com)
  • Corneal and crystalline lens parameters in children who became myopic were compared with age-, gender-, and ethnicity-matched model estimates of emmetrope values annually from 5 years before through 5 years after the onset of myopia. (ovid.com)
  • abstract = "We describe a non-invasive phakometric method for determining corneal axis rotation relative to the visual axis (β) together with crystalline lens axis tilt (α) and decentration (d) relative to the corneal axis. (aston.ac.uk)
  • The lens was then removed through an intracapsular cataract extraction type corneal incision. (escrs.org)
  • At 3 wk of age (postnatal day 21), lenses from null mice (Aqp0(-/-)) contained polymorphic opacities, whereas lenses from heterozygous mice (Aqp0(+/-)) were transparent and did not develop frank opacities until approximately 24 wk of age. (uniprot.org)
  • Morris MS, Jacques PF, Hankinson SE, Chylack LT, Willett WC, Taylor A. Moderate alcoholic beverage intake and early nuclear and cortical lens opacities. (harvard.edu)
  • Cataracts themselves are opacities of the lens and some may be small and not need treatment while others will be big enough to block light and perfect vision. (advancedvisioncare.co.uk)
  • We demonstrate an optimized optical platform for the three-dimensional (3-D) visualization of crystalline lens opacities in vivo in the eyes of patients with different types and grades of cataracts. (um.es)
  • The instrument might be a useful tool in the highresolution preoperative evaluation of crystalline lens opacities in cataract patients. (um.es)
  • Dominant mutations in the gene for AQP0 have been associated with lens opacities, or cataracts, in humans ( 11 ) and mice ( 26 , 28 , 29 ). (physiology.org)
  • With cataracts, the normally clear lens becomes cloudy, affecting the transmission of light through the lens and resulting in loss of visual acuity. (google.com.au)
  • There are a number of potential problems with the crystalline lens with, perhaps, cataracts being the best known. (advancedvisioncare.co.uk)
  • Cataracts usually develop as the lens becomes older and more opaque but they can be formed after an injury to the lens itself or congenitally. (advancedvisioncare.co.uk)
  • Cataracts can be operated on and the cataract surgery will see the removal of the lens and an artificial intraocular lens being inserted in its place. (advancedvisioncare.co.uk)
  • As people age, they face an increasing possibility of developing cataracts, characterized by opacity of the crystalline lens in the eye. (photonics.com)
  • Most cataracts arise because of ageing of the crystalline lens. (bmj.com)
  • Biology of the lens: lens transparency as a function of embryology, anatomy, and physiology. (springer.com)
  • Kasturi N., Matalia J. (2017) Anatomy of the Human Crystalline Lens. (springer.com)
  • Is the Subject Area "Lens (anatomy)" applicable to this article? (plos.org)
  • It contains lens fibers and amorphous, intercellular substance. (harvard.edu)
  • As the secondary lens fibers elongate from the equator, they form Y-shaped sutures by meeting anteriorly and posteriorly during fetal growth. (utah.edu)
  • The lens is held in place by zonular fibers, otherwise known as the zonules of Zinn (Fig. 4). (utah.edu)
  • As we age lens fibers grow denser and less elastic. (everydaysight.com)
  • 1959). Electron microscope study of lens fibers. (core.ac.uk)
  • 1960). Observations on a cytoplasmic component in lens fibers. (core.ac.uk)
  • Purpose: Actin and myosin inside the crystalline zoom lens keep up with the structural integrity of zoom lens fibers cells and type a hexagonal lattice cradling the posterior surface area from the zoom lens. (conferencedequebec.org)
  • The cells of the lens epithelium also serve as the progenitors for new lens fibers. (wikipedia.org)
  • The lens fibers form the bulk of the lens. (wikipedia.org)
  • These tightly packed layers of lens fibers are referred to as laminae. (wikipedia.org)
  • The lens fibers are linked together via gap junctions and interdigitations of the cells that resemble "ball and socket" forms. (wikipedia.org)
  • The lens is split into regions depending on the age of the lens fibers of a particular layer. (wikipedia.org)
  • Mature lens fibers have no organelles or nuclei. (wikipedia.org)
  • Postmitotic cells at the posterior of the vesicle elongate to fill the cavity with primary fibers forming the embryonic lens. (physiology.org)
  • The lens is suspended in place by the zonular fibers, which attach to the lens near its equatorial line and connect the lens to the ciliary body. (newworldencyclopedia.org)
  • At short focal distances, the ciliary muscles contract, zonule fibers loosen, and the lens thickens, resulting in a rounder shape and thus high refractive power. (newworldencyclopedia.org)
  • Rao PV, Zigler JS, Garland D. Analysis of small GTP-binding proteins of the lens by GTP overlay assay reveals the presence of unique GTP-binding proteins associated with fiber cells. (harvard.edu)
  • The crystalline lens is a transparent structure of the eye filled with proteins called crystallins. (everydaysight.com)
  • Despite numerous studies, major unanswered questions are how this heterogeneous group of proteins becomes organized to bestow the lens with its unique optical properties and how it changes during cataract formation. (core.ac.uk)
  • 1972). Electron microscope observations on some structural proteins of the chick lens. (core.ac.uk)
  • 1980). Identification of the cytoskeletal proteins in lens-forming cells, a special epitheloid cell type. (core.ac.uk)
  • 2006). The C terminus of lens aquaporin 0 interacts with the cytoskeletal proteins filensin and CP49. (core.ac.uk)
  • Conclusions: Cytoskeletal proteins disruptors resulted in a decreased rigidity from the zoom lens, and the consequences had been reversible. (conferencedequebec.org)
  • However, their efficiency in generating photo-induced oxidative modifications on eye lens proteins is not completely understood. (ku.dk)
  • In this work, the efficiency and photodynamic activity of 3OHKN bound to both lysine (3OHKN-Lys) and bovine lens proteins (3OHKN-BLP) was assessed and compared with the photosensitizing activity of the major chromophore arising from glucose degradation (GDC). (ku.dk)
  • In humans, the refractive power of the lens in its natural environment is approximately 18 dioptres, roughly one-third of the eye's total power. (wikipedia.org)
  • In humans, the refractive power of the lens in its natural environment is approximately 18 dioptres . (wikipedia.org)
  • It is synthesized by the lens epithelium and its main components are type IV collagen and sulfated glycosaminoglycans (GAGs). (wikipedia.org)
  • The cells of the lens epithelium regulate most of the homeostatic functions of the lens. (wikipedia.org)
  • Visual simulation using low and high contrast corrected distance visual acuity (CDVA) testing was carried out with the VAO instrument (Voptica, SL, Murcia, Spain), considering three optical conditions of the lens: removing HOA (no lens-HOA), removing spherical aberration (no lens-SA), and with lens HOA (natural condition). (healio.com)
  • Purpose: To investigate the relationships between visual acuity, contrast sensitivity, and 11 clinicopathologic classes of opacity in the human crystalline lens. (gla.ac.uk)
  • 23-gauge PPV was performed, and it has been used perfluorcarbon liquid to remove the lens from the vitreous cavity. (escrs.org)
  • Likewise, on the posterior surface area from the avian crystalline zoom lens, f-actin, non-muscle myosin, and N-cadherin are organized within a hexagonal lattice resembling a two-dimensional muscles [15]. (conferencedequebec.org)
  • bifocal lens one having two segments with different refracting power, the upper for far vision and the lower for near vision. (thefreedictionary.com)
  • omnifocal lens one whose power increases continuously and regularly in a downward direction, avoiding the discontinuity in field and power inherent in bifocal and trifocal lenses . (thefreedictionary.com)
  • The lens can be replaced with a monofocal (monovision) lens or by multifocal (bifocal/trifocal) lenses. (institutmacula.com)
  • Of all the techniques being used to correct presbyopia, at the Institut de la Màcula we recommend replacing the transparent crystalline lens with a multifocal lens implant (bifocal/trifocal) or a monofocal lens with monovision, or advanced monovision, as these are the safest, most stable, effective and definitive methods available today. (institutmacula.com)
  • Whether you are near sighted, far sighted, or have never worn eyeglasses at all, you may need to wear a bifocal lens or reading glasses at some point in your life. (avesis.com)
  • Can I have Progressive or Bifocal lenses fitted on any frame? (glassesusa.com)
  • Not all frames can be fitted with progressive or bifocal (line) lenses. (glassesusa.com)
  • However, in humans and model organisms, little is known about the factors that determine the dimensions of the crystalline lens and in particular whether these different parameters (axial thickness, surface curvatures, equatorial diameter, and volume) are under a common source of control or regulated independently of other aspects of eye size and shape. (cf.ac.uk)
  • In addition, the MRI lens thickness estimates had a lower mean value and much higher variance. (cf.ac.uk)
  • However, since it has been shown previously that axial lens thickness is regulated almost independently of eye and body size, these results suggest that different systems might operate to control lens volume/diameter and lens thickness in normal chickens. (cf.ac.uk)
  • The lens has an ellipsoid, biconvex shape. (everydaysight.com)
  • Biconvex means the lens is curved outward on both sides. (everydaysight.com)
  • The biconvex lens of the eye. (thefreedictionary.com)
  • biconvex lens one convex on both faces. (thefreedictionary.com)
  • Indeed, about one-third of crystalline lenses showed a kidney-shaped appearance instead of the typical biconvex shape. (cf.ac.uk)
  • Light rays converge when passing through a biconvex lens (top) and diverge when passing through a biconcave lens (bottom).f indicates the focus. (thefreedictionary.com)
  • 5. a body of rock or ore that is thick in the middle and thinner toward the edges, similar in shape to a biconvex lens. (thefreedictionary.com)
  • The crystalline lens is a transparent , biconvex structure in the eye . (wikipedia.org)
  • For the lens to work, the ciliary muscles change the shape of the lens which enables the eye to focus on objects at different distances. (advancedvisioncare.co.uk)
  • The ciliary muscles control the convexity (outward curvature) of the lens in response to the distance of the object being viewed. (everydaysight.com)
  • Imagine the ciliary muscles surrounding the lens as a tiny doughnut. (everydaysight.com)
  • In the relaxed state the ciliary muscles pull on the zonules increasing their tension on the lens. (everydaysight.com)
  • The lens becomes stiff making it more difficult for the ciliary muscles to change the shape of the lens causing impaired vision. (everydaysight.com)
  • Furthermore, the current 1092788-83-4 supplier presence of extremely regular actomyosin lattices in the zoom lens raises the chance that these systems get excited about setting the unaggressive biomechanical response from the avian zoom lens to external pushes, such as for example those exerted with the ciliary muscles. (conferencedequebec.org)
  • For example, since Dr Schachar proposed an alternative mechanism of how the ciliary muscles change the shape of the lens, there has been much argument and counter-argument. (sciencelearn.org.nz)
  • Learn more about the Schachar mechanism of how the ciliary muscles and zonular fibres change the shape of the lens here . (sciencelearn.org.nz)
  • However, changes in the lens's curvature from continual growth as well as loss of power of the ciliary muscles (the muscles that bend and straighten the lens) have also been postulated as causal or contributing factors. (newworldencyclopedia.org)
  • The lens is flexible and its curvature is controlled by ciliary muscles through the zonules. (newworldencyclopedia.org)
  • By changing the curvature of the lens with these tiny ciliary muscles, one can focus the eye on objects at different distances from it. (newworldencyclopedia.org)
  • Changing focus to an object at a distance requires the stretching of the lens by the ciliary muscles, which flattens the lens and thus increases the focal distance. (newworldencyclopedia.org)
  • Many texts, though, describe the ciliary muscles (which seem more likely to be just elastic ligaments and not under any form of nervous control) as pulling the lens taut in order to focus at close range. (newworldencyclopedia.org)
  • It has long been recognized in the art that contact lenses must remain free of surface deposits in order to maintain their wearing comfort and optimum vision and reduce the potential for ocular change. (google.com)
  • Unfortunately, contact lenses are susceptible to acquiring surface deposits from exogenous sources (mascara, hair spray, etc.) and endogenous sources (mucous, oily meibomian secretions, etc. (google.com)
  • Silicone containing contact lenses are the most vulnerable of all contact lenses to the acquisition of tenacious, waxy surface deposits that are difficult, if not impossible, to totally remove without damaging the lens. (google.com)
  • Other cleaning agents have employed thixotropic synthetic water soluble polymers and thixotropic synthetic clays with detergents to give stiff gels for the cleaning of hard contact lenses. (google.com)
  • Abrasives are employed in the manufacturing of contact lenses in a polishing process which provides the contact lens with optical quality surfaces. (google.com)
  • It is an object of this invention to provide a contact lens cleaning material which consists essentially of a surface active agent, an inorganic abrasive and a suspending vehicle which material is highly useful as a cleaner enabling superior cleaning of silicone-containing plastic contact lenses while also useful as a cleaner and/or cleaner/polisher for other contact lens materials. (google.com)
  • The lens dimensions were compared to measures of eye and body size obtained in vivo using techniques that included keratometry and A-scan ultrasonography. (cf.ac.uk)
  • The combination of advanced glaucoma and phacodonesis with lens subluxation suggests pseudoexfoliation (PXF) syndrome, which needs to be ruled out. (crstoday.com)
  • Lens subluxation can also occur in conditions such as Marfan syndrome, Ehlers-Danlos syndrome, and congenital aniridia syndrome. (everydaysight.com)
  • Early anatomists viewed the lens as the location of meaningful visualization. (utah.edu)
  • The lens relies on the aqueous humor for nutrition and waste removal. (everydaysight.com)
  • If the zonules appeared pathologic and the lens seemed to be unstable as the case began, I would place retractors from the Mackool Cataract Support System (Duckworth & Kent Ltd., Hertfordshire, United Kingdom) as I performed the capsulorhexis. (crstoday.com)
  • The lens and zonules. (springer.com)
  • The delicate, yet strong zonules connect to the ciliary body to suspend the lens in position. (everydaysight.com)
  • The zonules pull on the lens around its equator causing the entire lens to become flatter, or less convex. (everydaysight.com)
  • When the zonules loosen, the lens thickens, or becomes rounder in shape. (everydaysight.com)
  • A blunt injury to the eye can disrupt the zonules dislocating the lens in any direction. (everydaysight.com)
  • Nevertheless, the adjustments in the human being zoom lens happen via the rest of zonules mounted on the ciliary muscle mass [1,3], whereas the ciliary muscle mass in the avian vision directly articulates using the equator from the zoom lens [2], producing a squeezing from the zoom lens 1092788-83-4 supplier in the equatorial aircraft. (conferencedequebec.org)
  • It is attached to the lens by zonules (ligament fibres that can be tight or loose). (sciencelearn.org.nz)
  • Lens transparency depends on the accumulation of massive quantities (600-800 mg/ml) of twelve primary crystallines and two truncated crystallines in highly elongated "fiber" cells. (core.ac.uk)
  • 1985). Physical basis of lens transparency. (core.ac.uk)
  • The zoom lens keeps its integrity and transparency because of the business of its cells, that are epithelial in source [4-6]. (conferencedequebec.org)
  • In conclusion, P. densiflora bark extract prevented selenite-induced cataract formation via regulating antioxidant enzymes, inhibiting m -calpain-induced proteolysis, and apoptosis, and thus, maintained the transparency of the lens. (molvis.org)
  • The transparency of the lens is maintained by many interdependent factors that are responsible for its optical homogeneity, including its microscopic structure and chemical constituents. (bmj.com)
  • 13 . A method that minimizes cataract formation when an agent is provided to an ocular lens, the method comprising piercing the lens with a needle of 30 gauge or thinner, introducing an agent into the lens through the needle, and withdrawing the needle from the lens. (google.com.au)
  • In: The Ocular Lens: Structure, Function and Pathology. (core.ac.uk)
  • Garland DL, Duglas-Tabor Y, Jimenez-Asensio J, Datiles MB, Magno B. The nucleus of the human lens: demonstration of a highly characteristic protein pattern by two-dimensional electrophoresis and introduction of a new method of lens dissection. (harvard.edu)
  • During lenticular development, the hyaloid artery delivers nutrition and growth factors through the tunica vasculosa lentis, a vascular structure that envelopes the lens nucleus. (utah.edu)
  • The results showed lens micro- and macro-scale features related to possible cataract development such as cortical spokes, water clefts and enhanced scattering in the lens nucleus. (um.es)
  • 2006). Quantitative measurement of young human eye lens crystallins by direct injection Fourier transform ion cyclotron resonance mass spectrometry. (core.ac.uk)
  • The developing optic cup induces the lens placode to be formed from the surface ectoderm (2). (utah.edu)
  • Subjects must have elected to undergo lens extraction and foldable monofocal IOL implantation (ideally of the same type), and then elect to have the LensAR laser surgery. (clinicaltrials.gov)
  • Microincisional PPV can be combined with differents procedures and it is a safe and effective surgical method in the treatment of a subluxated or completely dislocated crystalline lens and retained lens fragments secondary to complicated cataract extraction, trauma or spontaneously. (escrs.org)
  • The lenses of New Zealand White and Flemish Giant rabbits were removed using five techniques representative of the different clinical approaches to extracapsular cataract extraction currently employed. (nih.gov)
  • Although many projects are being developed to treat presbyopia, the only definitive treatment currently available for its correction is extraction of the crystalline lens which is, due to the age-related loss of accommodation, the cause of the appearance of presbyopia. (institutmacula.com)
  • Retrospective descriptive study of three clinical cases with posteriorly dislocated crystalline lens based on information from clinical records, patient observation, surgery record and analysis of complimentary diagnostic tests. (escrs.org)
  • The increased curvature of the lens gives it the highest refractive power to enable us to focus on objects up close. (everydaysight.com)
  • Light from a single point of a distant object and light from a single point of a near object being brought to a focus by changing the curvature of the lens. (wikipedia.org)
  • Due to potential problems with centration, the lens should be spherical or neutrally aspheric. (crstoday.com)
  • as the tension is relaxed the lens becomes more spherical in shape and hence more convex. (thefreedictionary.com)
  • Nevertheless, the disruptors didn't affect the clearness from 1092788-83-4 supplier the lens (p0.4696 for everyone disruptors), nor did they have an effect on spherical aberration (p = 0.02245). (conferencedequebec.org)
  • The treatment of cataract involves surgical removal of the old lens and implantation of a new artificial intraocular lens. (molvis.org)
  • The crystalline particulate material can be incorporated into the light bulb material prior to the molding or forming process or it can be later applied to the surfaces of the light bulb. (google.com.au)
  • Wet-chemical production of amorphous or crystalline metal oxide nanoparticles for self-cleaning surfaces, sun blockers, semiconductor sensors and catalytic convertors. (innovations-report.com)
  • The cleaning process involves removal of contaminants from the surfaces of the contact lens without scratching or otherwise affecting the lens material. (google.com)
  • Before myopia onset, the crystalline lens thinned, flattened, and lost power at similar rates for emmetropes and children who became myopic. (ovid.com)
  • Myopia onset is characterized by an abrupt loss of compensatory changes in the crystalline lens that continue in emmetropes throughout childhood axial elongation. (ovid.com)
  • The lens is suspended in place by the suspensory ligament of the lens, a ring of fibrous tissue that attaches to the lens at its equator and connects it to the ciliary body. (wikipedia.org)
  • This means that the ciliary muscle is no longer able to sufficiently change the shape of the lens. (sciencelearn.org.nz)
  • Problem in Quantitalive Evaluation of Posterior Capsular Opacification Using the Crystalline Lens Image Analysis Method. (worldwidescience.org)
  • To decrease the burden of surgery, preventive interventions of lens opacification are continually sought. (molvis.org)
  • Actin and myosin within the crystalline lens maintain the structural integrity of lens fiber cells and form a hexagonal lattice cradling the posterior surface of the lens. (uwaterloo.ca)
  • The consequences of most three disruptors had been reversible, with lens dealing with treatment with actin, myosin, and MLCK disruptors after 4 h, 1 h, and 8 min, respectively. (conferencedequebec.org)
  • Nevertheless, partial coherent interferometry cannot penetrate dense lenses as well as ultrasound biomicroscopy. (photonics.com)
  • Optical dysfunction of the crystalline lens in aquaporin-0-deficient mice. (uniprot.org)
  • Individual differences between the no lens-HOA condition and the other two optical conditions, estimated as 95% limits of agreement, were acceptable for 3-mm pupil but worse as pupil diameter increased. (healio.com)
  • To demonstrate the feasibility of quantifying the internal human crystalline lens structure using Optical Coherence Tomography (OCT). (arvojournals.org)
  • Optical distances were divided by published values of the average refractive index of the lens to produce true distances (Uhlhorn et al, Vis Res 2008). (arvojournals.org)
  • The number of discrete zones of optical discontinuity is correlated with the age of the lens. (arvojournals.org)
  • The study demonstrates the feasibility of imaging the zones of optical discontinuity of the in vitro and in vivo lenses using OCT. (arvojournals.org)
  • Here we present preliminary results on phase sensitive spectral domain optical coherence tomography (PhS-SDOCT) measurements of the vibrations induced on surface of an eye lens. (spie.org)
  • Chen Wu, Salavat R. Aglyamov, Zhaolong Han, Manmohan Singh, Chih-Hao Liu, and Kirill V. Larin, "Assessing the biomechanical properties of the porcine crystalline lens as a function of intraocular pressure with optical coherence elastography," Biomed. (osapublishing.org)
  • In this study, we investigated the relationship between the biomechanical properties of the crystalline lens and intraocular pressure (IOP) using a confocal acoustic radiation force (ARF) and phase-sensitive optical coherence elastography (OCE) system. (osapublishing.org)
  • electrical leads connecting said base with said source of lighting, wherein said housing and said optical element each have structure that causes wide dispersion of light traveling from said source of lighting to said optical opening, said structure including a mixture of moldable material and transparent particulate crystalline material. (google.com.au)
  • The optical properties of the eye lens are dependent upon a functional intermediate filament cytoskeleton. (core.ac.uk)
  • The mechanism where this happens in vertebrates entails the translation from the zoom lens or a big change in the zoom lens curvature to improve the optical power of the attention [1]. (conferencedequebec.org)
  • For example, slit-lamp bio microscopy is used extensively to examine for postsurgery complications, and phakometry measures the radius of curvature of the crystalline lens using reflected images produced by the optical interfaces in the eye. (photonics.com)
  • Abrasive materials have not been used in contact lens cleaning solutions heretofore, perhaps because such abrasives would have the propensity to scratch or otherwise alter the surface of the plastic contact lens, thus leading to a reduction in optical clarity as well as enhanced eye irritation. (google.com)
  • There are also structural changes to the lens fibres, which result in disruption of the regular architecture and arrangement of the fibres that are necessary to maintain optical clarity. (bmj.com)
  • The 1-mm-thick silicon Fresnel lens was developed by researchers from the French aerospace lab Onera, French thermal imaging sensor company ULIS, the Optical Institute and the French National Center for Scientific Research. (photonics.com)
  • The immature lenticular cells thicken to form the lens placode. (utah.edu)
  • In adults, the lens is about 10mm across at the axis and 4mm from front to back. (everydaysight.com)
  • We used frequentist and Bayesian methods to predict the ages and age classes of harvested hog deer Axis porcinus from eye lens mass. (bioone.org)
  • A firm understanding of the embryology and development of the lens will provide great insight into the pathology associated with cataract formation. (utah.edu)
  • In the classic book, Eye and Brain (Gregory 1994), the lens is said to be suspended by a membrane, the zonula, which holds it under tension. (newworldencyclopedia.org)
  • Currently in cataract surgery, the opacified crystalline lens is replaced by a monofocal intraocular lens (IOL) with a power targeted to achieve emmetropia. (healio.com)
  • On the growth and internal structure of the human lens. (springer.com)
  • Eight isolated human lenses (31-90 y/o) were imaged with a custom-built time-domain system (Uhlhorn et al, Vis Res 2008) and 3 in vivo human lenses (24-34 y/o) were imaged with a custom-built extended-depth spectral-domain OCT system. (arvojournals.org)
  • Frost, N. A. , Sparrow, J. M. and Moore, L. (2002) Associations of human crystalline lens retrodots and waterclefts with visual impairment: an observational study. (gla.ac.uk)
  • 1996). Fiber cell morphology and cytoplasmic texture in cataractous and normal human lens nuclei. (core.ac.uk)
  • 1996). Morphology of the normal human lens. (core.ac.uk)
  • Development of the human lens begins at the 4 mm[clarification needed] embryonic stage. (wikipedia.org)
  • A clouding of the normally clear human lens inside the eye, causing vision to be blurred. (avesis.com)
  • A crystalline substance . (webster-dictionary.org)
  • Wollaston prisms are a type of prism made of two layers of a crystalline substance, such as quartz, which, due to the variation of refractive index depending on the polarisation of the light, splits the light according to its polarisation. (wikipedia.org)
  • The present light bulb includes a wide angle dispersed light which uses, as a source of light dispersion, crystalline particulate material incorporated into the molded or formed material of the light bulb. (google.com.au)
  • The crystalline particulate material can be incorporated into the light bulb material prior to. (google.com.au)
  • The crystalline particulate material are chosen to provide high reflectivity and dispersion qualities for the parts of the light bulb and are further chosen and incorporated according to the function of the particular piece or part therein incorporated. (google.com.au)
  • 3. The light bulb having widely dispersed light of claim 1 wherein said transparent particulate crystalline material is substantially symmetrical. (google.com.au)
  • 4. The light bulb having widely dispersed light of claim 1 wherein said transparent particulate crystalline material is selected from the group consisting of quartz crystals, diamond crystals, sapphire crystals, and zirconia crystals. (google.com.au)
  • 5. The light bulb having widely dispersed light of claim 1 wherein said transparent particulate crystalline material is present in said mixture from about 1 to 12 percent by weight, based on the total mixture composition. (google.com.au)
  • 6. The light bulb having widely dispersed light of claim 1 wherein said transparent particulate crystalline material has planes that are oriented in substantially the same direction. (google.com.au)
  • When you are looking at a near object, the lens needs to become more rounded at the central surface in order to focus the light rays. (sciencelearn.org.nz)
  • 9 . The foldable intraocular lens of claim 1 wherein said photochromic agent is present in an amount sufficient to be activated by the amount of light entering the eye. (google.co.uk)
  • 4. A device or phenomenon (such as a gravitational field) that causes light or other radiation to converge or diverge by an action analogous to that of a lens. (thefreedictionary.com)
  • 2. To bend or distort (light, for example) by means of a lens, especially a gravitational field. (thefreedictionary.com)
  • These devices have only been able to measure the refractive power properties of the eye, and factors such as the lens opacity of the eye which affect the light reflected from the eye fundus have usually been overlooked. (justia.com)
  • If the lens opacity of the eye to be examined is so great that the measuring light cannot reach to the fundus, prior devices have not been able to determine whether or not the reason is the lens opacity. (justia.com)
  • The lenses project light through long tubes to two retinas, which are stacked in series and highly asymmetric: they are horizontally extended and vertically very narrow. (biologists.org)
  • With ageing, there is a gradual accumulation of yellow-brown pigment within the lens, which reduces light transmission. (bmj.com)
  • The prototype lens has a 130° field of view, and performs well in low-light conditions, researchers said. (photonics.com)
  • The researchers admit that the new lens does not provide the highest resolution, but can effectively reveal the presence of a person, even in low-light settings. (photonics.com)
  • To evaluate the impact of the lens aberrations on the adaptive optics visual simulation of pseudophakic intraocular lens (IOL) profiles. (healio.com)