37 results about "Cornea repair" patented technology

The invention provides an application of a cross-linked decellularized bovine amniotic membrane (CAM) and manganese carbon dots (Mn CDs) combined in preparation of an ophthalmic medical material for alkali burn cornea repair. The invention further provides a compound for repairing the alkali burn cornea. Cell and animal experiments show that the compound CDs (at) CAM has good biocompatibility and strong antioxidant and anti-inflammatory effects, can significantly promote corneal epithelium regeneration and inhibit corneal neovascularization and scar generation, and provides a new strategy for treatment of alkali burn cornea and various corneal epithelium injuries and diseases.

The invention belongs to the technical field of biomedical materials, and relates to a high-adhesion Janus artificial cornea as well as a preparation method and application thereof. The invention provides an artificial cornea, which is characterized in that a coating containing epsilon-PLL and 4-arm-PEG-NHS is distributed on a collagen skeleton EB-Col, and the functional group ratio of-NHS to-NH2 in the coating is 1: (0.6-1.4), and the molar ratio is 1: (0.6-1.4). The invention also relates to a corresponding high-adhesion Janus artificial cornea, and a preparation method and application thereof. The artificial cornea has instant and stable adhesion capability, gives consideration to optical transparency and mechanical and adhesion properties, can well adapt to the shape of a wound, is convenient to use, high in practical operability and mild in reaction, and is particularly suitable for being applied to cornea repair materials in the ophthalmology department, and the strong wet tissue adhesion property of the artificial cornea can adapt to a dynamic ocular surface moist environment.

The invention discloses a PDRNamp and a method for preparing the PDRNamp. The invention discloses EGT eye wash as well as a preparation method and application thereof, and belongs to the technical field of eye care products. The eye wash is prepared from the following active components in percentage by mass: 0.001 to 0.01 percent of PDRN, 0.03 to 0.1 percent of EGT (Ergothioneine), sodium hyaluronate, sodium chloride, taurine and the like, wherein the mass percent of the PDRN is 0.001 to 0.01 percent, and the mass percent of the EGT is 0.03 to 0.1 percent. Through the synergistic effect of PDRN and EGT, the product has excellent cornea repairing capacity and a powerful anti-oxidation function at the same time, and the moisturizing and soothing effects are enhanced by compounding sodium hyaluronate and taurine. The obtained eye washing liquid is an isotonic solution with neutral pH, is mild and non-irritating, does not contain preservatives, can effectively achieve multiple nursing effects of eye cleaning, moisturizing, repairing, anti-inflammatory and anti-oxidation, and is suitable for relieving xerophthalmia, assisting cornea repair and daily anti-oxidation nursing of eyes.

The present invention discloses a preparation method of a collagen-bioactive glass anti-inflammatory corneal repair material, comprising the following steps: (1) blending and grinding bioactive glass with lecithin, and then drying in vacuum to obtain modified bioactive glass; (2) adding the modified bioactive glass prepared in step (1) into ultrapure water and ultrasonically mixing to obtain a uniform suspension; (3) blending the suspension obtained in step (2) with a collagen solution to obtain a uniform and bubble-free mixed solution at room temperature; (4) air-drying the mixed solution obtained in step (3) to obtain a collagen-bioactive glass anti-inflammatory corneal repair material. The present invention also discloses a collagen-bioactive glass anti-inflammatory corneal repair material obtained by the above preparation method. On the premise of meeting the requirements of mechanical properties, moisture content, light transmittance, etc. required for corneal regeneration and repair materials, the corneal repair material of the present invention can regulate the polarization of macrophages, thereby achieving the effect of regulating inflammation.

The invention discloses application of cnidium lactone in preparation of a medicine for treating AMD or corneal injury, and belongs to the field of biological medicine. It is found for the first time that the cnidium lactone can inhibit sodium iodate induced retinal pigment epithelial cell injury, and it is also found for the first time that the cnidium lactone can promote injured cornea repair; based on the discovery, the invention respectively provides application of cnidium lactone in preparation of medicines for treating age-related macular degeneration and preparation of medicines for treating corneal injury. Experimental results show that cnidium lactone can remarkably reverse the retinal pigment epithelial cell degradation trend caused by age-related macular degeneration and can also remarkably promote corneal notch healing. The invention provides a new optional medicine for treating age-related macular degeneration and corneal injury, expands the application range of cnidium lactone, and has outstanding clinical practical value and wide application prospect.

The invention relates to the technical field of medical preparations, in particular to moisturizing and repairing type artificial tear as well as a preparation method and application thereof. Comprising the following steps: preparing effective components including high-molecular-weight polydeoxyribonucleotide and hyaluronic acid or a salt thereof into a homogeneous-phase stable composite solution, sterilizing, filtering, and aseptically packaging, the artificial tear formed by selecting high-molecular-weight polydeoxyribonucleotide and high-molecular-weight sodium hyaluronate as effective components has a relatively good repairing effect on tissues, can form long-term moisturizing and lubrication on ocular surfaces, is suitable for treating xerophthalmia, repairing cornea, relieving inflammatory response and the like, and has a good application prospect. Important market values and clinical application prospects are realized.

The application discloses a kind of corneal near physiological biomechanics intelligent simulation method and device, it is related to biomechanics and biomechanics experimental device technical field, the present application includes mutually connected force load cavity, force loading component, sensor monitoring feedback component etc..The present application can realize to corneal repair material, corneal cell, corneal cell-material compound loading individual and compound flow shear force, static pressure, dynamic pressure, static tension and dynamic tension, gas-liquid dynamic culture is simultaneously carried out, and through pressure and flow sensor, the stress size of loading is monitored in real time, reach accurate intelligent comprehensive simulation cornea in body environment.The scheme provided by the present application can be used for the mechanical property detection of corneal tissue and material, obtains the material attribute under near physiological state;It can also be used for the mechanical loading of cell, to observe the cell behavior and functional change after near physiological mechanical loading.

The invention discloses a modified phoenix ovi cornea repair material as well as a preparation method and application thereof, an EDTA-imidazole mixed solution is used for efficiently removing a calcium carbonate shell layer of an egg, and no calcium residue exists. Soaking treatment is carried out under the optimized alkali concentration to realize partial denaturation of main structural protein, so that the natural fiber network of the hen egg membrane becomes loose, and the optical clarity is improved while the mechanical integrity is kept. Alkaline treatment further improves the physicochemical characteristics of the membrane, namely surface hydrophilicity, balanced water content and degradation rate, the saturated water content of the modified phoenix membrane is close to that of natural cornea, the degradation rate is matched with the regeneration and repair rate of cornea defects, and the phoenix membrane is endowed with excellent antibacterial performance through quaternary ammonification reaction. A New Zealand white rabbit anterior lamellar cornea cutting operation model is adopted to evaluate the cornea regeneration and repair curative effect, a modified phoenix membrane cornea repair material is implanted, coherent epithelium closure and ordered matrix remodeling of the cornea are effectively promoted, and the repaired cornea is consistent with a natural lossless cornea in function.

The invention discloses an encapsulated mesenchymal stem cell microneedle modified cornea stroma lens and a preparation method and application thereof, the cornea stroma lens is a cornea stroma lens generated from femtosecond laser small incision cornea microlens extraction (such as SMILE operation), and has excellent biocompatibility and transparency. The lens is modified by a microneedle structure, so that the lens can be accurately anchored to a cornea defect part, and meanwhile, the encapsulated mesenchymal stem cells locally and continuously release repair promoting factors to promote cornea cell regeneration and tissue repair. The preparation method is simple, high in universality and suitable for large-scale production, and based on reutilization of the myopia operation waste lens, the availability of materials is improved, waste of medical resources is reduced, and the myopia operation waste lens has important economic and clinical application prospects in the field of cornea repair.

The invention relates to the technical field of keratoprosthesis preparation, in particular to a biomimetic structure keratoprosthesis carrying a PRP microsphere slow release system and a preparation method of the biomimetic structure keratoprosthesis. PRP is encapsulated through PLGA microspheres, and stepped release of growth factors is achieved through degradation controllability of PLGA; the PRP-PLGA microspheres still keep a stable slow-release effect within 14 days in vitro, the problem that growth factors are rapidly inactivated due to direct application of traditional PRP is effectively solved, the treatment window period is remarkably prolonged, and continuous biological activity stimulation needed by cornea repair is met; by utilizing the degradation controllability of the PLGA, the stepped release of the growth factor is realized, so that the stable release effect of the PRP can be maintained for a long time after the artificial cornea is transplanted, the treatment window period after the artificial cornea is transplanted is prolonged, and the continuous biological activity stimulation required by cornea repair is met.

The utility model relates to a matrix lens corneal donor based on hydrogel bonding, and the corneal donor comprises a plurality of layers of corneal matrix lenses which are stacked along the thickness direction of the corneal matrix lenses; and the bonding layer is bonded between two adjacent cornea stroma lenses, and the bonding layer comprises composite material hydrogel which forms a grid porous structure after being cured. The stacked multiple layers of cornea stroma lenses are bonded to the preset thickness through the combined adhesive, so that the cornea donor has high structural strength, the problem of sliding or twisting deformation in the surgical suture process is effectively avoided, a grid porous structure is formed after composite hydrogel is cured, and the cornea donor has a good application prospect. The air permeability and the structural strength of the matrix lens cornea donor based on hydrogel bonding are guaranteed, and the reliability of cornea repair is improved.

The invention relates to an aquatic animal-derived acellular matrix injection which comprises an acellular matrix, a stabilizer and a pH regulator, and a preparation method of the aquatic animal-derived acellular matrix injection. The invention also relates to an application of the aquatic animal-derived acellular matrix injection in preparation of a product for wound repair, or an application in preparation of a product for surgical operations, or a product for bone defect repair, cartilage defect repair, cornea repair, tissue thickening and residual cavity filling.

The invention provides gradient bio-ink of a three-dimensional bionic corneal stroma scaffold and a 3D printing preparation process. The gradient bio-ink comprises 5-30 parts of a natural polymer matrix, 2-8 parts of a bioactive factor, 1-5 parts of a cell component, 1-10 parts of a light curing agent and 60-95 parts of normal saline. The natural polymer matrix contains methylacryloylated gelatin, a collagen / hyaluronic acid protein compound and chitosan, and the collagen / hyaluronic acid protein compound is prepared through lysyl oxidase cross-linking and visible light photocuring. After the bio-ink is prepared, an extrusion type 3D printer is adopted for printing layer by layer under specific conditions, ultraviolet irradiation is synchronously performed, and the three-dimensional bionic corneal stroma scaffold is prepared. The scaffold disclosed by the invention has good mechanical properties, light transmission and cell compatibility, can support directional differentiation of stem cells, and is suitable for cornea repair.

According to the application of the doxycycline and the compound composition of the doxycycline in preparation of the corneal injury repairing medicine, corneal collagenase is inhibited through the doxycycline, repairing of corneal epithelium is facilitated, and the oculentum preparation can act on cornea more enduringly, so that corneal repairing of alkali burn patients, dry eye patients and ocular surface injury patients is promoted, and the curative effect of the oculentum preparation is improved. According to the eye ointment, corneal epithelial cells can be effectively treated, regeneration and healing of the corneal epithelial cells are accelerated, hormones and non-steroidal anti-inflammatory components are added, ocular surface inflammatory response can be specifically inhibited, symptoms such as red and swollen eyes and pain can be relieved, the repairing effect of corneal epithelium can be enhanced, all the components are uniformly dispersed in the eye ointment by optimizing the preparation process, the stability of the eye ointment is guaranteed, and the eye ointment has good application prospects. The phenomena of layering, devitrification and the like are not easy to occur in the storage process, and stable and reliable product quality is ensured.

The application discloses an oxygen-enriched recombinant human I / V type collagen corneal repair gel and a preparation method thereof. Methyl methacrylic acid is added into recombinant human I / V type collagen to prepare a methyl methacrylate anhydride recombinant human collagen RHC-I / V-MA solution, the solution is dissolved in an EDC solution for reaction for 2-4 hours to obtain a RHC-I / V-MA-EDC sponge-like solid sample, then the sample is dissolved in a photoinitiator to obtain a mixed solution, an oxygen-containing gas is continuously introduced into the mixed solution by using a micro-nano bubble generator, the flow rate of the oxygen-containing gas is 0.1-2 L / min, and the oxygen-containing gas is introduced for 1-15 minutes to obtain the oxygen-enriched recombinant human I / V type collagen corneal repair gel. The light transmittance of the oxygen-enriched recombinant human I / V type collagen corneal repair gel is extremely high in a spectral range of 400-700 nm, the oxygen-enriched recombinant human I / V type collagen corneal repair gel has good optical stability, is suitable for repairing a corneal transparent layer and provides a material selection with excellent optical performance for corneal repair.

The invention provides a hydrogel for corneal repair and a preparation method thereof, the hydrogel for corneal repair comprises the following raw materials by weight: 100 parts of thiolated hydroxyethyl chitosan; 20 to 40 parts of hyaluronic acid; and 10 to 20 parts of N-methyl-D-glucosamine. The hydrogel for corneal repair is used as a drug carrier, has good adhesiveness with cornea and good cell compatibility, can reduce inflammatory response caused by long-term contact with the cornea, and promotes regeneration and repair of corneal cells.

The application provides application of calcium folinate in preparation of corneal repair promoting drugs and belongs to the technical field of ophthalmic drugs. The application uses calcium folinate as an active ingredient of a drug for treating corneal injury, has a good treatment effect on corneal epithelial injury and corneal nerve injury, and the calcium folinate is low in price and easy to store. The application provides a calcium folinate eye drop solution, which comprises calcium folinate and physiological saline; the mass percentage content of the calcium folinate in the calcium folinate eye drop solution is 0.1-1%. Compared with the drugs commonly used in the clinic for promoting repair after corneal injury, the calcium folinate eye drop solution provided by the application is low in price, can reduce the medical expenditure of patients to a certain extent, and reduces the medical burden of patients. Meanwhile, the composition of the calcium folinate is single, the calcium folinate is easy to store and not prone to deterioration, and the application of the calcium folinate to a certain extent avoids the risk that the existing corneal repair promoting eye drop solution is continuously used after being contaminated and deteriorated, which may cause or aggravate the infection risk.

The invention discloses oxygen-enriched recombinant human I / V type collagen cornea repair gel and a preparation method thereof.The preparation method comprises the steps that methacrylic acid is added into recombinant human I type collagen and recombinant human V type collagen, a methacrylic anhydride recombinant human collagen RHC-I / V-MA solution is prepared and then dissolved in an EDC solution, a reaction is conducted for 2-4 h, and an RHC-I / V-MA-EDC spongy solid sample is obtained; dissolving in a photoinitiator to obtain a mixed solution; a micro-nano bubble generator is adopted to continuously introduce oxygen-containing gas into the mixed solution, the introduction flow of the gas is 0.1-2 L / min, the introduction time is 1-15 min, and the oxygen-enriched recombinant human I / V type collagen cornea repair gel is obtained. The material prepared by the method has high light transmittance in a spectral range of 400-700nm, has good optical stability, is suitable for repairing a cornea transparent layer, and provides a material selection with excellent optical performance for cornea repair.

The invention belongs to the technical field of biological medicine, and particularly relates to PSA-Dex polymer nanoparticles, a preparation method thereof and application of the PSA-Dex polymer nanoparticles in corneal inflammation. The invention firstly provides a sialic acid glycan-dexamethasone polymer nanoparticle for treating inflammatory reaction caused by corneal burn, and the sialic acid glycan-dexamethasone polymer nanoparticle is formed by self-assembly of a sialic acid glycan-dexamethasone polymer. The synthesized nanoparticles can release Dex drugs in a faintly acid eye environment in a responsive manner, so that responsive, efficient, accurate and targeted delivery of the drugs is realized, the cornea penetrating power of the drugs is enhanced, and the effects of enhancing the anti-inflammatory effect and promoting cornea repair are achieved.

The invention provides a structure bionic collagen corneal graft and a preparation method thereof. The preparation method of the collagen corneal graft with the bionic structure comprises the following steps: S1, dissolving collagen to prepare a collagen solution; s2, adding a cross-linking agent into the collagen solution to carry out a cross-linking reaction; and S3, carrying out bubble removal, molding, freeze thawing, freeze drying, washing and drying on the cross-linking reaction product to prepare the structure bionic collagen corneal graft. The water content of the collagen cornea graft with the bionic structure is similar to that of a natural cornea, the light transmittance performance is good, the light transmittance and a light transmittance curve in a visible light range are not greatly different from those of tissues, the ion permeability performance and the biomechanical performance are good, and the requirements of nutrient substance transportation and eyeball supporting and protecting effects can be met; particularly, the cornea graft has excellent suture resistance, can bear suture and tearing of operation lines, and has a good cornea repair effect.

The invention discloses a water-soluble cellulose derivative-silk fibroin artificial tear with the characteristics of long-acting retention and no irritation and a preparation method thereof. The artificial tear comprises a water-soluble cellulose derivative, silk fibroin, an osmotic pressure regulator, a pH regulator and water. After the water-soluble cellulose derivative is dissolved, a transparent viscous colloid can be formed, a protective film can be formed on the ocular surface, a tear film is stabilized, tear evaporation is delayed, friction is reduced, and dryness and foreign body sensation are rapidly relieved. The polar group of the silk fibroin and the silk fibroin form a stable network through a hydrogen bond, eyelid shearing and tear erosion are resisted, the bioavailability of the silk fibroin is improved, and the silk fibroin has the effects of resisting inflammation and promoting corneal epithelium repair. The osmotic pressure regulator and the pH regulator are cooperated, so that the osmotic pressure and the pH value of the artificial tear approach to those of human tears, the ocular surface is prevented from being stimulated, and the medication comfort and compliance are improved. The artificial tear can quickly relieve the dry eye symptom, realizes long-acting cornea repair, and provides a new strategy for development of a high-efficiency long-acting eye drug delivery system.

The invention provides a novel artificial tear containing recombinant human lysozyme, the novel artificial tear comprises a main component and an auxiliary material, the main component is recombinant human lysozyme, and based on the total mass of the novel artificial tear, the content of the recombinant human lysozyme is greater than or equal to 0.015% and less than 0.075%. The novel artificial tear contains recombinant human lysozyme with lower concentration and has better repairing and anti-inflammatory effects, and compared with the high-concentration artificial tear and the low-concentration artificial tear, the novel artificial tear has more obvious effects of increasing tear secretion, promoting cornea repairing and resisting inflammation. The raw material of the recombinant human lysozyme is derived from the recombinant human lysozyme stock solution, and the pH and osmotic pressure molar concentration value adjustment is not needed in the artificial tear preparation process, so that the large-scale production process can be greatly simplified, and the large-scale production stability is improved.

The invention relates to the field of medicines, in particular to fluoroalkanes, and a composition, a preparation method and application thereof. The invention has the following advantages: the invention provides fluoroalkane, and a composition, a preparation method and application thereof; the compound shown in the formula (I) or the pharmaceutically acceptable salt, the stereoisomer, the isotope variant, the solvate or the composition of the compound has the effects of stabilizing a tear film, dissolving meibolipid, dissolving earwax, inhibiting evaporation of water on the ocular surface, increasing the thickness of a tear film lipid layer, improving the spreadability of cornea, wetting the surface of the eye, preserving an isolated organ, improving the stability of the cornea and improving the quality of the eye. The pharmaceutical composition has the effects of improving the stability of a tear film, reducing the evaporation rate of tears, prolonging the rupture time of the tear film, treating meibomian fat abnormity, treating meibomian gland dysfunction, treating keratoconjunctivitis sicca, treating eye or ear related diseases such as xerophthalmia related diseases and / or delivering active pharmaceutical ingredients.

The invention discloses a nano ophthalmic gel preparation for treating corneal epithelium injury. The main component of the nano ophthalmic gel preparation is PIP nano gel; the preparation method of the PIP nanogel comprises the following steps: preparing cystamine dihydrochloride modified carboxymethyl cellulose from cystamine dihydrochloride modified carboxymethyl cellulose, taking collagen as an auxiliary material, loading a drug component PIP under the action of electrostatic self-assembly, and synthesizing the PIP nanogel. The hydrated particle size of the synthesized PIP nanogel is 50 to 500 nm. The ball-like PIP nanogel with good dispersion is proposed and successfully prepared for the first time, the blank that no suitable PIP delivery system exists in the prior art is filled, and a new technical path is provided for in-vivo application of PIP; the prepared nano ophthalmic gel preparation can prolong the PIP eye residence time to 12 hours or more, so that the cornea repair speed is increased by 50% or more compared with that of a free PIP group, and wound closure is accelerated.

The invention belongs to the technical field of medicine preparation, and particularly relates to a nano-micelle medicine for treating xerophthalmia and a preparation method of the nano-micelle medicine. According to the invention, sodium caseinate is adopted as an auxiliary material to construct the nano preparation co-loaded with resveratrol RES and curcumin CUR, so that the oral bioavailability of resveratrol and curcumin is synchronously enhanced, and the targeting distribution of drugs in eye tissues can be optimized. Resveratrol focuses on anti-inflammatory, anti-oxidation and neuroprotection, and curcumin is good at regulating an Nrf2 anti-oxidation pathway and promoting corneal repair and mucoprotein secretion. According to the invention, the two natural active components, namely the resveratrol RES and the curcumin CUR, are combined for treating the dry eye, and the two components can achieve a synergistic effect, so that the curative effect of the nano-micelle medicine on the dry eye syndrome is effectively improved, and the dry eye symptom is relieved.

The invention relates to a drug-loaded hydrogel eye pad as well as a preparation method and application thereof, and belongs to the technical field of eye care and pharmaceutical preparations. The drug-loaded hydrogel eye pad is composed of a hydrogel matrix and active components uniformly dispersed in the hydrogel matrix, the active components are salvianolic acid B and geniposide, and the mass ratio of the salvianolic acid B to the geniposide is 4: 1-1.5: 1. According to the drug-loaded hydrogel eye patch provided by the invention, gelatin and chitosan are taken as matrixes, a hydrogel network is formed through genipin crosslinking, and salvianolic acid B and geniposide are loaded as active ingredients. Salvianolic acid B can inhibit release of inflammatory factors, improve microcirculation and promote corneal repair; the geniposide has remarkable anti-inflammatory, anti-oxidation and neuroprotective effects, and the geniposide and the geniposide synergistically play a role in treating xerophthalmia. The eye patch has good biocompatibility, adhesion and drug release performance, can effectively relieve xerophthalmia symptoms, and is simple in preparation process and suitable for large-scale production.

The invention discloses an atomized medicine composition for treating filamentous keratitis. The atomized medicine composition is prepared from the following raw materials in parts by weight: 12 parts of radix rehmanniae, 12 parts of radix achyranthis bidentatae, 12 parts of radix angelicae sinensis, 12 parts of fructus aurantii, 12 parts of rhizoma seu radix notopterygii, 15 parts of radix saposhnikoviae, 9 parts of rhizoma chuanxiong, 20 parts of flos chrysanthemi, 9 parts of periostracum cicadae, 12 parts of herba schizonepetae, 15 parts of radix paeoniae alba, 9 parts of herba equiseti hiemalis, 15 parts of fructus lycii and 12 parts of semen cassiae. The preparation method comprises the following steps: injecting clear water into the mixed raw materials to submerge the Chinese herbal medicines, standing and soaking for half an hour, decocting to 200ml by slow fire, and filtering the medicine residue to obtain the atomized medicine composition for treating filamentous keratitis. 20-30ml of the liquid medicine is taken each time. The medicine composition can be used for treating filamentous keratitis, directly acts on eyes in a traditional Chinese medicine atomization mode, and is taken once a day, and 20-30 ml of medicine is taken once; the pharmaceutical composition disclosed by the invention is high in safety and small in side effect, and can achieve the curative effects of clearing liver, improving eyesight and removing nebula; the composition is combined with a cornea repairing agent to take effect quickly and has a good curative effect.

The present invention discloses a patterned collagen-based artificial cornea loaded with miR-133b@BG-NH2 and a preparation method thereof. The invention comprises the following steps: synthesizing mesoporous bioactive glass (BG) by a sol-gel method; modifying the surface of BG with amino groups using a silane coupling agent (APTES) to obtain amino-modified mesoporous bioactive glass (BG-NH2); utilizing BG-NH2 as a carrier of miR-133b, and co-incubating the two to obtain miR-133b@BG-NH2 nanoparticles; dissolving collagen by an acid dissolution method to obtain a collagen solution, adding a cross-linking agent for cross-linking; blending the collagen solution with miR-133b@BG-NH2 to obtain a mixed solution, stirring to remove bubbles, pouring the solution into a PDMS mold with a microgroove structure, and naturally air-drying the solution to form a film; immersing the film in a cross-linking agent and cross-linking it again, and air-drying the film to obtain the product. The method of the present invention is easy to implement, and the obtained artificial cornea has good biocompatibility, similar transparency to that of a natural cornea, and meets the mechanical properties and regulatable degradation properties required for corneal repair.