Analysis from the perspective of cilia: the protective effect of PARP inhibitors on visual function during light-induced damage.

PURPOSE: To analyze the protective effect of PARP inhibitors on light-damaged retina and explore its possible mechanism from the perspective of ciliopathy. METHODS: A systematic review of the literature was performed to investigate the protection of PARP inhibition on light-damaged cilia. PubMed database was retrieved to find the relevant studies and 119 literatures were involved in the review. RESULTS: In retina, the outer segment of photoreceptor is regarded as a special type of primary cilium, so various retinal diseases actually belong to a type of ciliopathy. The retina is the only central nervous tissue exposed to light, but poly (ADP-ribose) polymerase (PARP), as a nuclear enzyme repairing DNA breaks, is overactivated during the light-induced DNA damage, and is involved in the cell death cascade. Studies show that both ATR and phosphorylated Akt colocalize with cilium and play an important role in regulating ciliary function. PARP may function at ATR or PI3K/Akt signal to exert protective effect on cilia. CONCLUSION: PARP inhibitors may protect the cilia/OS of photoreceptor during light-induced damage, which the possible mechanism may be involved in the activation of ATR and PI3K/Akt signal.

UV damage of the anterior ocular surface - microstructural evidence by in vivo confocal microscopy.

PURPOSE: To evaluate and describe the microstructural changes at the ocular surface in response to habitual ocular sun exposure, correlate them with the UV protection habits and follow their dynamics using in vivo confocal microscopy(ICM). METHODS: For a period of minimum 4 months 200 subjects (400 eyes), aged 28 ±â€¯7.3 years, were recruited with the agreement that they will spend their summer exclusively in the region of the Black Sea coast at 43 °N latitude and will be examined before and after the summer. All subjects filled in a questionnaire about habitual UV protection and were examined clinically and by ICM. RESULTS: Questionnaire results demonstrated that 83.5% (167 participants) of the subjects considered the sun dangerous for their eyes, but 78% (156 subjects) believed that there is danger exclusively during the summer period. Although no clinical changes were detected, microstructural analysis of the cornea demonstrated statistically significant (p = 0.021) decrease of the basal epithelial density - from 6167 ±â€¯151 cells/mm2 before to 5829 ±â€¯168 cells/mm2 after the summer period. Microstructural assessment of the conjunctiva demonstrated characteristic cystic lesions with dark centres and bright borders encountered in only 25 eyes(6%) before, and affecting 118 eyes(29.5%) after the summer. The total area of the cysts after the summer increased fivefold. Spearman analysis proved negative correlation between sun protection habits and number of cysts. CONCLUSION: Summer sun exposure for one season leads to clinically undetectable, microstructural changes affecting the cornea, bulbar and palpebral conjunctiva with transient, but possibly cumulative nature.

[How to improve the prevention and treatment of ocular chemical burns in China: important elements].

Ocular chemical burns are common and serious ocular emergencies which require immediate and intensive evaluation and treatment. Loss of vision and disfigurement affect the victims, bringing great sufferings to themselves and their families. China is the biggest developing country in the world with a large number of such cases. The prevention of ocular chemical burns is emphasized in different aspects. After emergency treatment, proper care of chemical burns is started by control of inflammation with corticosteroids. Topical and systemic ascorbic acid supplement is important. Re-epithelialization is critical to stabilize the ocular surface and to prevent corneal ulceration and melting. The goal of treatment is mainly to restore the ocular structure and function. Neuroprotection is important during the treatment course for control of both glaucoma and inflammation. Prognosis depends on the degree of limbal, corneal and conjunctival involvement at the time of injury as well as the management. Medical treatments only or with combination of surgical procedures, including amniotic membrane transplantation, epithelial or limbal stem cell transplantation, tenonplasty, keratoplasty and keratoprosthesis, are according to the classification of ocular chemical burns and the phases. Further investigations should be done in the future in both prevention and management of ocular chemical burns in China. (Chin J Ophthalmol, 2018, 54: 401-405).

Triptolide Suppresses Alkali Burn-Induced Corneal Angiogenesis Along with a Downregulation of VEGFA and VEGFC Expression.

Triptolide (TPL) is an active compound extracted from a Chinese herbal medicine tripterygium wilfordii Hook. f. (Celastraceae), which has been used as an anti-inflammatory drug for years. It also inhibits the growth and proliferation of different types of cancer cells. The inhibitory effect of TPL on angiogenesis after chemical-induced corneal inflammation was studied in vivo. The effects of TPL on the proliferation, apoptosis, migration, and tube formation of rat aortic endothelial cells (RAECs) were studied in vitro. Cell proliferation and apoptosis were measured by MTT assay and flow cytometry, respectively. Migration was analyzed using the scratch wound healing assay and transwell assay. Tube formation assay was used to examine angiogenesis. Real-time PCR and Western blot were used to determine the expression of vascular endothelial growth factor A (VEGFA) and VEGFC. To study the in vivo effects of TPL, the mouse model of alkali burn-induced corneal angiogenesis was used. The angiogenesis was analyzed by determining the density of the newly generated blood vessels in corneas. We found that TPL induced apoptosis and inhibited the proliferation of RAECs in a dose-dependent manner. TPL inhibited migration and tube formation of RAECs and decreased the expression of VEGFA and VEGFC in vitro. Furthermore, TPL suppressed alkali burn-induced corneal angiogenesis and inhibited the expression of VEGFA and VEGFC in corneas in vivo. In conclusion, topical TPL as a pharmacological agent has the ability to reduce angiogenesis in cornea and may have clinical indications for the treatment of corneal angiogenesis diseases which have to be further explored. Anat Rec, 300:1348-1355, 2017. © 2017 Wiley Periodicals, Inc.

Thermodynamic measurement after cooling the cornea with intact epithelium and lid manipulation.

PURPOSE: To characterize the rate of change of ocular surface temperature (OST) under lid manipulation after cooling the intact cornea with balanced salt solution (BSS). METHODS: In a patient for refractive surgery, prior to the ablation, the temperature of the cornea was continuously recorded with a high speed infrared (350Hz) camera. Two millilitre of chilled BSS with a temperature of 8.6°Celsius (°C) was instilled for about 3s. Using exponential functions, the three contributions have been determined, subjacent corneal layers, environment, and chilled BSS. RESULTS: The mean temperature of the cornea preoperatively was 34.5°C. After applying the chilled BSS the temperature decreased about 14°C down to an OST of 20°C and the time needed afterwards to get the normal (OST) temperature of about 30°C was 40s. Due to the inserted speculum and missing blink, OST did not reach the original OST of 34.5°C and faded at about 32.5°C. According to our best fitted model, absolute value of each contributing component was 31.4°C (subjacent corneal layers), 26.8°C (environment) and 8.6°C (BSS). CONCLUSIONS: Applying chilled BSS to the cornea quickly reduces the temperature of the cornea with a thermal relaxation time of 3s and a amplitude decrease of 8.6°C. This together with a relaxation time of 7s for subjacent corneal layers, and 184s for environment after instillation of BSS combined with a well-controlled environment provides a period of 40s of corneal temperature below baseline, which may be of clinical benefit when applying chilled BSS immediately before or immediately after ablation.

Knowledge, attitude and practice regarding solar ultraviolet exposure among medical university students in Northeast China.

To assess the knowledge, attitudes and practices regarding the health effects of ultraviolet radiation (UVR) and sun exposure among medical university students in Northeast China, 385 subjects were investigated on October 2013 using a self-administered multiple-choice questionnaire. Most of the subjects knew the effects of UVR on skin cancer (95.6%) and sunburn (92.2%), but fewer knew of the eye damage that can result from UVR (27.8% cataract and 3.1% pterygium). Correspondingly, the main purpose of adopting sun protection was considered to be 'preventing sunburn' (55.4%), but 'preventing eye damage' was the least (1.8%). In actual behaviour, the eyes received the least protection as well. Although knowing the effects of UVR on vitamin D synthesis (87.3%), 66.8% of participants never or seldom increased sun exposure. Compared to men, women were more likely to reduce sun exposure (P<0.001). Only a small fraction of subjects (6.6%) thought that tanning was attractive. Considering the response variability to UVR in people with different skin colours, different sun protection programs should be provided. In China, especially in the North, the public should be educated to moderately increase sun exposure to maintain adequate vitamin D status while also protecting against eye damage from UVR.

Inhibition of corneal neovascularization after alkali burn: comparison of different doses of bevacizumab in monotherapy or associated with dexamethasone.

BACKGROUND: To compare the effects of different doses of bevacizumab with both saline and dexamethasone on inflammatory angiogenesis in the rat cornea induced by small chemical lesions. METHODS: Corneal chemical cauterization was performed on 24 rats. Animals were divided randomly into six groups and received a daily subconjunctival injection for 7 days of: balanced salt solution 0.1 mL or dexamethasone phosphate 4 mg/day or bevacizumab 2.5 mg/day, 3.75 mg/day, 5.0 mg/day or bevacizumab 5.0 mg/day + dexamethasone phosphate 4 mg/day. Clinical examination under slitlamp was performed daily for 7 days to evaluate corneal opacity and vessel size evolution. Computer assisted quantitative image analysis was used to measure the total corneal area covered by neovascularization. RESULTS: At final examination, the dexamethasone, bevacizumab 5.0 mg/day and dexamethasone + bevacizumab groups showed a significant lowering in corneal opacity score as compared with control (P = 0.024, P = 0.006 and P = 0.013, respectively). Also, a significant reduction on new vessels size score was observed. Surface of corneal neovascularization was significantly reduced in dexamethasone, bevacizumab 5.0 mg/day and dexamethasone + bevacizumab groups compared with control (P =0.045, P = 0.047 and P = 0.044, respectively). CONCLUSION: Our study demonstrates the ability of a 5.0 mg/day bevacizumab subconjunctival injection, in monotherapy or associated with dexamethasone, to cause a short-term involution of corneal neovascularization after corneal alkali burn. Combination of both of these treatments may have advantages to monotherapy approaches.

Use of sunglasses in public outdoor recreation settings in Honolulu, Hawaii.

PURPOSE: Approximately, 20.5 million Americans (17.2%) older than 40 years have a cataract in at least one eye, and rates are expected to rise to over 30 million by 2020. Wearing sunglasses, especially early in life, may reduce the risk of cataracts. Meanwhile, little is known about the prevalence of wearing sunglasses in the United States, especially in areas with high ultraviolet radiation. The objective of this study was to assess the prevalence and predictors of wearing sunglasses in public outdoor recreation settings. METHODS: Systematic observations were made at beaches, parks and outdoor public swimming pools in Honolulu, Hawaii on sunny days between November 2005 and June 2007. Observations were conducted independently by two trained observers between 10:00 am and 4:00 pm. During each observation period, each individual in the area was coded for gender, age category, clothing coverage, shade use, and use of sunglasses. RESULTS: A total of 5171 people were observed by two independent observers, and the inter-rater reliability use of sunglasses was excellent (Cohen kappa = 0.83). Overall, 33.0% of people wore sunglasses. chi analysis revealed that significantly more people (p < 0.001) wore sunglasses at swimming pools (35.1%) and parks (34.8%) compared to beaches (30.4%). Adults (41.6%) were more likely to wear sunglasses than children (12.3%; p < 0.001). Gender was not significantly associated (p = 0.3) with the use of sunglasses (males = 32.7%; females = 33.3%). Those wearing hats were significantly more likely (p < 0.001) to wear sunglasses (46.6%) than those with bare heads (28.4%). CONCLUSIONS: Direct observation in public outdoor recreation settings revealed that only one third of the population wore sunglasses. Further research should examine the use of sunglasses in other locations and investigate the effectiveness of interventions that promote the wearing of sunglasses in settings with risk for ultraviolet radiation exposure.

Laser safety in dentistry.

Although many regulations and standards relating to laser safety are in effect, there continue to be an average of 35 laser injuries per year. Laser safety professionals believe that this number under-represents the actual number of injuries and that many more accidents per year occur that are not documented with federal agencies. A review of these accidents has determined that failing to wear available eye protection is one of the most frequent contributing factors to laser injuries. As the purchase and use of lasers in dentistry continues to grow, so must concern for laser safety. This article provides basic information to advance the safe use of lasers in dentistry and to help establish laser safety protocols for the dental office.

[Ocular burns]. / Brûlures oculaires.

Ocular or thermal burns account for 7.7%-18% of ocular trauma. The majority of victims are young. The burns occur in the setting of accidents at work or in the home, or during a physical attack. Chemical burns by strong acids or bases are responsible for the most serious injuries. Associated with the destruction of limbal stem cells, they present as recurrent epithelial ulcerations, chronic stromal ulcers, deep stromal revascularization, conjunctival overlap, or even corneal perforation. The initial clinical exam is sometimes difficult to perform in the presence of burning symptoms. Nevertheless, it enables the physician to classify the injury, establish a prognosis, and most importantly, guide the therapeutic management. The Roper-Hall modification of the Hughes classification system is the most widely utilized, broken down into stages based on the size of the stromal opacity and the extent of possible limbal ischemia. This classification is now favorably supplemented by those proposed by Dua and Wagoner, which are based on the extent of the limbal stem cell deficiency. The prognosis of the more serious forms of ocular burns has markedly improved over the last decade because of a better understanding of the physiology of the corneal epithelium. Surgical techniques aimed at restoring the destroyed limbal stem cells have altered the prognosis of severe corneal burns. In order to decrease the incidence of burns, prevention, particularly in industry, is essential.

Functional efficacy of glatiramer acetate treatment for laser-induced retinal damage in rats.

BACKGROUND AND OBJECTIVES: To functionally evaluate the efficacy of glatiramer acetate (Cop-1) as a neuroprotective treatment for laser-induced retinal injuries in rats. STUDY DESIGN/MATERIALS AND METHODS: Using standard lasering and flash ERG techniques, we evaluated the effect of photocoagulation and of Cop-1 treatment on retinal function 3, 20, and 60 days after covering one-half of the retina with of 23 rats with argon laser lesions. RESULTS: Significant neuroprotective effects of Cop-1 treatment on functional recovery were observed 20 and 60 days after retinal photocoagulation. Two months post-lasering, the amplitude of electroretinographic signals in lasered eyes (mean+/-SEM) was 99.5+/-10.2% of that of intact eyes in the Cop-1-treated group and 85.8+/-5.5% in the untreated lasered control group (P<0.05). CONCLUSIONS: Cop-1 immunization in rats is neuroprotective against laser-induced injuries to the outer retina and improves functional recovery of the injured retina. Studies have documented effective neuroprotective treatment after laser damage to myelinated neurons, but this is the first report of neuroprotection of nonmyelinated neurons.

Cooling prevents induction of corneal damage by argon laser peripheral iridotomy.

PURPOSE: There are many reports of corneal complications caused by argon laser peripheral iridotomy. In this study, we investigated whether cooling the anterior ocular segment during laser iridotomy prevented corneal damage. METHODS: A space for cooling the anterior ocular segment by perfusion with ice-cold water was made between the cornea and a contact lens. Dutch pigmented rabbits were excessively irradiated by an argon green laser, aiming at the peripheral iris. We used a contact lens without a cooling system as a control. Temperature in the anterior chamber and intraocular pressure were also monitored throughout the experiment. RESULTS: During laser treatment, the temperature without the cooling system rose to a maximum of 44.5 degrees C in the anterior chamber, whereas use of the cooling system consistently kept this temperature at 11.1 degrees -16.1 degrees C. Although most eyes treated without cooling showed corneal damage, damage was seen in only a few or in no eyes cooled during laser treatment. CONCLUSIONS: Argon laser treatment using contact lenses with a cooling system drastically reduced the corneal damage induced by argon laser peripheral iridotomy. This technique may be acceptable for clinical use, considering its technical simplicity and low incidence of treatment-related complications.

Quantitative thermographic analysis of viscoelastic substances in an experimental study in rabbits.

PURPOSE: To measure the temperature parameters on the corneal surface during the delivery of standardized ultrasound energy assisted with ophthalmic viscosurgical devices (OVDs) or different temperatures of irrigating solutions in an experimental animal model. SETTING: Department of Ophthalmology and Visual Rehabilitation, Medical University of Lodz, and Central Institute for Labor Protection, National Research Institute, Warsaw, Poland. METHODS: Thirty rabbits (60 eyes) were randomly divided into 6 groups in which different OVD or balanced salt solutions (BSS) were used: group 1: Viscoat (sodium hyaluronate 3%-chondroitin sulfate); group 2: Provisc (sodium hyaluronate 1%); group 3: soft-shell technique; group 4: Celoftal (hydroxypropyl methylcellulose 2%); group 5: BSS 22 degrees C; and group 6: BSS 4 degrees C. After the nucleus and lens cortex were removed, the anterior chamber was filled with OVD or BSS and a phaco tip was introduced into the pupillary plane and switched on. The same phaco tip parameters were used in all groups. For thermographic measurements (ie, maximal temperature [MT], dynamic rise in temperature [DRT], and time when the maximal level of temperature [TMLT] was achieved), a thermocamera was used. RESULTS: Mean preoperative temperature on the rabbit corneal surface was 22.76 degrees C +/- 1.48 degrees C (SD). Working with a phaco tip increased the temperature in each group. A significantly higher MT was observed in group 5 (27.85 degrees C +/- 0.52 degrees C), followed by group 2 (27.75 degrees C +/- 0.54 degrees C), group 3 (27.74 degrees C +/- 0.46 degrees C), and group 4 (27.25 degrees C +/- 0.60 degrees C), than in group 6 (26.81 degrees C +/- 0.34 degrees C) and group 1 (26.52 degrees C +/- 0.48 degrees C) (P<.05). Significantly higher values of DRT and shorter TMLT values were observed in group 5 (1.16 degrees C/s +/- 0.42 degrees C/s, 4 seconds) and group 6 (0.91 degrees C/s +/- 0.13 degrees C/s, 5 seconds) than in groups 2, 3, 1, and 4 (0.09 degrees C/s +/- 0.07 degrees C/s, 30 seconds; 0.08 degrees C/s +/- 0.04 degrees C/s, 40 seconds; 0.07 degrees C/s +/- 0.03 degrees C/s, 45 seconds; 0.06 degrees C/s +/- 0.02 degrees C/s, 50 seconds, respectively) (P<.0001). CONCLUSIONS: Currently used OVDs potentially offer different levels of protection against the increase in temperature that occurs during phacoemulsification. Therefore, the surgeon should consider this aspect when choosing an OVD, particularly in difficult cases (ie, hard nucleus, shallow anterior chamber, endothelial abnormalities).

Determination of eye safety filter protection factors associated with retinal thermal hazard and blue light photochemical hazard for intense pulsed light sources.

An assessment is provided of protection factors afforded for retinal thermal hazard and blue light photochemical hazard for a range of filters used with intense pulsed light sources (IPLs). A characteristic IPL spectrum based on black body radiation at 5000 K with a low cut filter at 515 nm was identified as suitable for such estimations. Specific filters assessed included types with idealized transmission properties and also a range of types whose transmission characteristics were measured by means of a Bentham DMc150 spectroradiometer. Predicted behaviour based on these spectra is outlined which describes both the effectiveness of protection and the level of luminous transmittance afforded. The analysis showed it was possible to describe a figure of merit for a particular filter material relating the degree of protection provided and corresponding value of luminous transmittance. This consideration is important for providing users of IPL equipment with safety eyewear with adequate level of visual transmittance.

Corneal endothelial cells' protection against thermal injury: influence of ophthalmic viscoelastic substances in experimental study on rabbits.

PURPOSE: To quantify the maximal level of temperature and the time the maximal temperature is achieved and correlate the temperature parameters to the mean rate of endothelial cell loss after standardized ultrasound delivery assisted with four viscoelastic substances or different temperature of balanced salt solution (BSS). METHODS: Thirty rabbits (60 eyes) were divided into six groups in which different viscoelastic substances or different temperature of BSS were used: Group 1, Viscoat; 2, Provisc; 3, soft shell technique; 4, Celoftal; 5, BSS 22 degrees C; and 6, BSS 4 degrees C. The same parameters of ultrasound energy were delivered by standard phaco tip introduced into pupillary plane. Thermocamera was employed for measurements of temperature parameters. Endothelium cell count was measured before surgery and 1 month postoperatively. RESULTS: Maximal level of temperature was measured as follows: Group 5, 27.85 +/- 0.52 degrees C; Group 2, 27.75 +/- 0.54 degrees C; Group 3, 27.74 +/- 0.46 degrees C; Group 4, 27.25 +/- 0.60 degrees C; Group 6, 26.81 +/- 0.34 degrees C; Group 1, 26.52 +/- 0.48 degrees C (p<0.05). The time the maximal temperature is achieved was statistically shorter in Groups 5 and 6: 4 seconds, 5 seconds, respectively, p<0.0001, as compared with Group 2 (30 seconds), Group 3 (40 seconds), Group 1 (45 seconds), and Group 4 (50 seconds). The mean rate of endothelial cell loss was calculated as follows: Group 1, 4.35%+/-2.55%; Group 2, 8.43%+/-5.2%; Group 3, 6.25%+/-4.20%; Group 4, 6.53%+/-4.65%; Group 5, 14.3%+/-3.85%; and Group 6, 8.78%+/-4.45%. CONCLUSIONS: Viscoelastic substances offer different levels of endothelial cell protection against temperature increase during phacoemulsification. The mean rate of endothelial cell loss correlates with the time the maximal temperature is achieved rather than with the value of maximal level of temperature. This implicates that surgical strategy should consider the choice of the most effective viscoelastic substances, particularly in difficult cases, e.g., hard nucleus, shallow anterior chamber, primary endothelial abnormality.

Safe exposure times for slit-lamp fundus biomicroscopy with high plus lenses.

PURPOSE: The purpose of this study was to calculate the retinal irradiance and maximum permissible exposure time (MPE) using high plus fundus biomicroscopy lenses. METHODS: Four Volk handheld condensing lenses (+78 D, +90 D, Superfield NC, and Super 66) were tested with biomicroscopes from three manufacturers (Nikon, Topcon, and Zeiss) on both high and medium illumination. Using the conservation of radiance theorem, the retinal irradiance was calculated and. with guidelines from the American National Standard Institute (ANSI). the maximum permissible exposure time was determined. RESULTS: The range of MPE time across all lenses and biomicroscopes was from 23 seconds to 74 seconds on high illumination setting. The average MPE times were: for the +78 D, 36 seconds; the Superfield NC, 57 seconds; the Super 66, 32 seconds; and the +90 D, 52 seconds. CONCLUSION: Retinal irradiances and safe exposure times are useful guidelines in both the clinical and academic setting. Fundus biomicroscopy with non-contact high plus condensing lenses produced calculated retinal irradiances and MPE times similar to those of other commonly used ophthalmic equipment. Awareness of the maximum permissible exposure time increases the safety of this valuable technique.

[Total eclipse of the sun in August 11, 1999: a program of prevention and surveillance of ocular complications]. / Eclipse totale de soleil du 11 août 1999: programme de prévention et surveillance des complications oculaires.

Watching directly at the sun without appropriate protection, particularly during a solar eclipse, can cause severe retinal injuries. On 11 August 1999, a total solar eclipse crossed France. The Direction Générale de la Santé implemented a prevention strategy. A formal agreement was developed with manufacturers and importers of protective glasses and more than 30 million glasses, conformed with safety standards, were distributed in France. Information campaign reach the whole population in France. In order to evaluate the impact of this campaign, The National Institute of Public Health in France implemented a nation-wide surveillance of ocular complications related to the eclipse. Information on patients was collected using a standardised questionnaire. The questionnaire was sent to the 5,600 private and public sector ophthalmologists practising in France and to five hundred hospital emergency units. A total of 147 patients were reported to have had a retinal injury associated with viewing the eclipse. Seventeen cases were severe (visual acuity < 2/10th) of whom 7 had bilateral injury. Forty-four per cent of patients were aged 15 to 29 years and 46% viewed the eclipse in three regions in the south of France which were sunny on 11th August. One hundred and six patients (67% aged 30 years and more) presented with keratitis. Thirty-six per cent occurred in 2 northern regions of France, which were overcast on the day. A hundred patients watched the whole eclipse without any protection, 74 reported to have removed their EC glasses, and 32 used non-appropriate devices. Only 4 patients presenting with retinal injury reported having used the EC glasses the whole time whilst viewing the eclipse. France is the only country in Europe to have implemented an exhaustive prospective surveillance of ocular injuries related to the solar eclipse. According to current data, the quality and availability of EC glasses did not contribute significantly to ocular injuries. Clinical and epidemiological studies are being conducted in order to further document the evolution of patients presenting with retinal injuries, the circumstances of observation, and their comprehension of preventive messages.