• Klíčová slova
• CORNEA/abnormalities *,
• MeSH
• rohovka abnormality   MeSH
• Publikační typ
• časopisecké články MeSH

• Klíčová slova
• CORNEA/abnormalities *,
• MeSH
• rohovka abnormality   MeSH
• Publikační typ
• časopisecké články MeSH

Mammalian corneal development is a multistep process, including formation of the corneal epithelium (CE), endothelium and stroma during embryogenesis, followed by postnatal stratification of the epithelial layers and continuous renewal of the epithelium to replace the outermost corneal cells. Here, we employed the Cre-loxP system to conditionally deplete Pax6 proteins in two domains of ocular cells, i.e., the ocular surface epithelium (cornea, limbus and conjunctiva) (OSE) or postnatal CE via K14-cre or Aldh3-cre, respectively. Earlier and broader inactivation of Pax6 in the OSE resulted in thickened OSE with CE and limbal cells adopting the conjunctival keratin expression pattern. More restricted depletion of Pax6 in postnatal CE resulted in an abnormal cornea marked by reduced epithelial thickness despite increased epithelial cell proliferation. Immunofluorescence studies revealed loss of intermediate filament Cytokeratin 12 and diffused expression of adherens junction components, together with reduced tight junction protein, Zonula occludens-1. Furthermore, the expression of Cytokeratin 14, a basal cell marker in apical layers, indicates impaired differentiation of CE cells. Collectively, our data demonstrate that Pax6 is essential for maintaining proper differentiation and strong intercellular adhesion in postnatal CE cells, whereas limbal Pax6 is required to prevent the outgrowth of conjunctival cells to the cornea.

• Klíčová slova
• Conditional knockout, Cornea, Development, E-cadherin, Eye, Keratins, Pax6,
• MeSH
• keratin-12 metabolismus   MeSH
• keratin-14 metabolismus   MeSH
• keratiny metabolismus   MeSH
• proteiny těsného spoje metabolismus   MeSH
• rohovka * metabolismus   MeSH
• rohovkový epitel * metabolismus   MeSH
• savci metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• keratin-12 MeSH
• keratin-14 MeSH
• keratiny MeSH
• proteiny těsného spoje MeSH

PURPOSE: To identify the molecular genetic cause in four families of various ethnic backgrounds with cornea plana. METHODS: Detailed ophthalmological examination and direct sequencing of the KERA coding region in five patients of Czech and Turkish origin and their available family members. RESULTS: Compound heterozygosity for a novel missense mutation c.209C>T; p.(Pro70Leu) and a novel splice site mutation c.887-1G>A in KERA were detected in two affected siblings of Czech origin. In silico analysis supported the pathogenicity of both variants. The second proband of Czech origin harboured c.835C>T; p.(Arg279*) in a homozygous state. Homozygous mutations c.740A>G; p.(Asn247Ser) and c.674C>T; p.(Ile225Thr) were identified in the Turkish probands, both born out of consanguineous marriages. Observed ocular phenotypes were typical of cornea plana with the exception of one Czech patient who also had marked thinning and protrusion in the superior part of the left cornea (mean keratometry 47.2 D). No corneal endothelial cell pathology was found by specular microscopy in seven eyes, in three eyes visualization of the posterior corneal surface was unsuccessful. CONCLUSION: KERA mutation c.740A>G has been identified to date in three different populations, which makes it the most frequently occurring mutation in patients with cornea plana. Marked corneal thinning and ectasia are a very rare finding in this disorder and longitudinal follow-up needs to be performed to determine its potential progressive nature.

• Klíčová slova
• KERA, cornea plana, novel mutation, phenotype,
• MeSH
• abnormality očí genetika   metabolismus   patologie   MeSH
• DNA genetika   MeSH
• lidé MeSH
• missense mutace * MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mutační analýza DNA MeSH
• nemoci rohovky vrozené   diagnóza   MeSH
• optická koherentní tomografie MeSH
• předškolní dítě MeSH
• proteoglykany genetika   metabolismus   MeSH
• rodokmen MeSH
• rohovka abnormality   metabolismus   MeSH
• senioři MeSH
• sourozenci * MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Geografické názvy
• Turecko MeSH
• Názvy látek
• DNA MeSH
• KERA protein, human MeSH Prohlížeč
• proteoglykany MeSH

The Purpose of present study was to investigate the effect of riboflavin/ultraviolet-A-induced collagen cross-linking (CXL) on central cornea, limbus and intraocular pressure (IOP). This was an animal experimental study. The right corneas of 10 rabbits were ultraviolet-A irradiated (3 mW/cm2 for 30 minutes) after de-epithelialization and instillation of 0.1% riboflavin / 20% Dextran drops. Left corneas served as controls. Samples were examined histologically one month postoperatively. Before and after treatment, IOP measurements were recorded bilaterally. At central cornea of eyes underwent CXL keratocyte repopulation, normal arrangement of collagen fibres and a statistically significant change in fibres diameter were detected, compared to controls. At limbus area, there were not any significant histological differences after CXL. There was no statistically significant difference between pre- and postoperative IOP in all eyes.

• Klíčová slova
• Cornea, Corneal Crosslinking, Intraocular pressure, Limbus,
• MeSH
• fotosenzibilizující látky farmakologie   MeSH
• kolagen chemie   ultrastruktura   MeSH
• králíci MeSH
• limbus corneae účinky léků   účinky záření   chirurgie   ultrastruktura   MeSH
• nitrooční tlak * účinky léků   účinky záření   MeSH
• reagencia zkříženě vázaná farmakologie   MeSH
• riboflavin farmakologie   MeSH
• rohovka účinky léků   účinky záření   chirurgie   ultrastruktura   MeSH
• ultrafialové záření * MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fotosenzibilizující látky MeSH
• kolagen MeSH
• reagencia zkříženě vázaná MeSH
• riboflavin MeSH

Oxidative stress is involved in many ocular diseases and injuries. The imbalance between oxidants and antioxidants in favour of oxidants (oxidative stress) leads to the damage and may be highly involved in ocular aging processes. The anterior eye segment and mainly the cornea are directly exposed to noxae of external environment, such as air pollution, radiation, cigarette smoke, vapors or gases from household cleaning products, chemical burns from splashes of industrial chemicals, and danger from potential oxidative damage evoked by them. Oxidative stress may initiate or develop ocular injury resulting in decreased visual acuity or even vision loss. The role of oxidative stress in the pathogenesis of ocular diseases with particular attention to oxidative stress in the cornea and changes in corneal optical properties are discussed. Advances in the treatment of corneal oxidative injuries or diseases are shown.

• MeSH
• alkálie toxicita   MeSH
• oční roztoky terapeutické užití   MeSH
• oxidační stres * účinky léků   účinky záření   MeSH
• poranění rohovky farmakoterapie   metabolismus   patologie   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• rohovka účinky léků   účinky záření   MeSH
• ultrafialové záření MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• alkálie MeSH
• oční roztoky MeSH
• reaktivní formy kyslíku MeSH

Cholinergic innervation of the cornea and iris of the newborn and adult guinea pig was studied by the technique of Karnovsky and Roots (1964). The given structures are both richly innervated. The cholinesterase reaction of the cornea is more strongly positive in adult animals, whereas the intensity of the reaction of the iris in newborn and adult guinea pigs is almost identical.

• MeSH
• acetylcholin fyziologie   MeSH
• iris inervace   MeSH
• morčata anatomie a histologie   MeSH
• rohovka inervace   MeSH
• zvířata MeSH
• Check Tag
• morčata anatomie a histologie   MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• acetylcholin MeSH

Xanthine oxidoreductase (xanthine dehydrogenase + xanthine oxidase) is a complex enzyme that catalyzes the oxidation of hypoxanthine to xanthine, subsequently producing uric acid. The enzyme complex exists in separate but interconvertible forms, xanthine dehydrogenase and xanthine oxidase, which generate reactive oxygen species (ROS), a well known causative factor in ischemia/reperfusion injury and also in some other pathological states and diseases. Because the enzymes had not been localized in human corneas until now, the aim of this study was to detect xanthine oxidoreductase and xanthine oxidase in the corneas of normal post-mortem human eyes using histochemical and immunohistochemical methods. Xanthine oxidoreductase activity was demonstrated by the tetrazolium salt reduction method and xanthine oxidase activity was detected by methods based on cerium ion capture of hydrogen peroxide. For immunohistochemical studies. we used rabbit antibovine xanthine oxidase antibody, rabbit antihuman xanthine oxidase antibody and monoclonal mouse antihuman xanthine oxidase/xanthine dehydrogenase/aldehyde oxidase antibody. The results show that the enzymes are present in the corneal epithelium and endothelium. The activity of xanthine oxidoreductase is higher than that of xanthine oxidase, as clearly seen in the epithelium. Further studies are necessary to elucidate the role of these enzymes in the diseased human cornea. Based on the findings obtained in this study (xanthine oxidoreductase/xanthine oxidase activities are present in normal human corneas), we hypothesize that during various pathological states, xanthine oxidase-generated ROS might be involved in oxidative eye injury.

• MeSH
• dospělí MeSH
• imunohistochemie MeSH
• lidé středního věku MeSH
• lidé MeSH
• peroxid vodíku farmakologie   MeSH
• reaktivní formy kyslíku MeSH
• rohovka enzymologie   MeSH
• xanthindehydrogenasa biosyntéza   MeSH
• xanthinoxidasa biosyntéza   metabolismus   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• peroxid vodíku MeSH
• reaktivní formy kyslíku MeSH
• xanthindehydrogenasa MeSH
• xanthinoxidasa MeSH

PURPOSE: Normal corneal hydration is necessary for the maintenance of corneal transparency. Damage of the corneal epithelium or endothelium by various external influences disturbs the mechanism by which the cornea maintains normal hydration and transparency. The cornea swells, and the corneal thickness increases, resulting in increased scatter and the development of corneal opacity. The transmission of light across the cornea is changed. The purpose of this study is to investigate spectrophotometrically the corneal light transmission under the influence of the various factors affecting the cornea. METHODS: We developed a spectrophotometric method to measure the light transmission across the cornea under the influence of various factors affecting the cornea, such as treatment with 0.9% NaCl, saline, or phosphate buffered saline (PBS), solutions employed as placebo eye drops (negative controls) in experimental studies, agents toxic to the cornea, such as diluted acids or alkalis. The method distinguishes between changes in corneal light transmission caused by altered corneal thickness (the level of hydration) and changes resulting from other corneal disturbances which in turn affect corneal light transmission. RESULTS: The results obtained show that the corneal light transmission is decreased following the application of toxic substances on the corneal surface. This decrease is highly dependent on the severity of the corneal injury evoked by individual noxes, and the resulting changes in corneal hydration and transparency. CONCLUSIONS: The influence of various influences applied to the cornea, manifested as changes in corneal light transmission, can be measured using our spectrophotometric method with a high degree of sensitivity.

• MeSH
• edém rohovky chemicky indukované   MeSH
• hydroxid sodný toxicita   MeSH
• králíci MeSH
• kyselina chlorovodíková toxicita   MeSH
• rohovka účinky léků   účinky záření   MeSH
• spektrofotometrie MeSH
• světlo * MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• hydroxid sodný MeSH
• kyselina chlorovodíková MeSH

The aim of this study was to examine the effect of molecular hydrogen (H2) on the healing of alkali-injured cornea. The effects of the solution of H2 in phosphate buffered saline (PBS) or PBS alone topically applied on the alkali-injured rabbit cornea with 0.25 M NaOH were investigated using immunohistochemical and biochemical methods. Central corneal thickness taken as an index of corneal hydration was measured with an ultrasonic pachymeter. Results show that irrigation of the damaged eyes with H2 solution immediately after the injury and then within next five days renewed corneal transparency lost after the injury and reduced corneal hydration increased after the injury to physiological levels within ten days after the injury. In contrast, in injured corneas treated with PBS, the transparency of damaged corneas remained lost and corneal hydration elevated. Later results-on day 20 after the injury-showed that in alkali-injured corneas treated with H2 solution the expression of proinflammatory cytokines, peroxynitrite, detected by nitrotyrosine residues (NT), and malondialdehyde (MDA) expressions were very low or absent compared to PBS treated injured corneas, where NT and MDA expressions were present. In conclusion, H2 solution favorably influenced corneal healing after alkali injury via suppression of oxidative stress.

• MeSH
• aktiny metabolismus   MeSH
• cytokiny metabolismus   MeSH
• exprese genu účinky léků   MeSH
• hydroxid sodný toxicita   MeSH
• imunohistochemie MeSH
• interleukin-1beta genetika   metabolismus   MeSH
• keratin-12 metabolismus   MeSH
• keratin-3 metabolismus   MeSH
• králíci MeSH
• kyselina peroxydusitá metabolismus   MeSH
• malondialdehyd metabolismus   MeSH
• modely nemocí na zvířatech MeSH
• oxidační stres účinky léků   MeSH
• poranění rohovky etiologie   metabolismus   patologie   MeSH
• rohovka metabolismus   patologie   MeSH
• vaskulární endoteliální růstový faktor A genetika   metabolismus   MeSH
• vodík farmakologie   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• publikace stažené z tisku MeSH
• Názvy látek
• aktiny MeSH
• cytokiny MeSH
• hydroxid sodný MeSH
• interleukin-1beta MeSH
• keratin-12 MeSH
• keratin-3 MeSH
• kyselina peroxydusitá MeSH
• malondialdehyd MeSH
• vaskulární endoteliální růstový faktor A MeSH
• vodík MeSH