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Sample records for rabbit eye due

  1. Rabbits' eye globe sonographic biometry.

    PubMed

    Toni, Maria Carolina; Meirelles, Adriana Érica Wilkes Burton; Gava, Fábio Nelson; Camacho, Aparecido Antônio; Laus, José Luiz; Canola, Júlio Carlos

    2010-11-01

    To measure intraocular structures in New Zealand White breed rabbits (Oryctolagus cuniculus Linnaeus, 1758) using A-mode and B-mode ultrasound with a 20 MHz transducer. In this study, the eyes of 15 rabbits were evaluated for determination of intraocular measurements using an ophthalmic ultrasound unit able to operate in both A and B-modes. The distances from the cornea to the anterior capsule of the lens (D1), from the anterior capsule of the lens to the posterior capsule of the lens (D2), from the posterior capsule of the lens to the retina (D3) and the complete length of the eye, which corresponds to the distance from the cornea to the retina (D4) were taken. The mean values obtained were 2.70 mm (± 0.22 mm) for D1, 7.32 mm (± 0.40 mm) for D2, 7.10 mm (± 0.45 mm) for D3 and 17.12 mm (± 0.41 mm) for D4. Statistical analyses using the Student's t-test showed that there were no differences between the eyes. The study was feasible without the need of pharmacological restraint and yielded normal mean values for ocular sonographic biometry in rabbits. © 2010 American College of Veterinary Ophthalmologists.

  2. In vivo femtosecond laser subsurface scleral treatment in rabbit eyes.

    PubMed

    Chai, Dongyul; Chaudhary, Gautam; Mikula, Eric; Sun, Hui; Kurtz, Ron; Juhasz, Tibor

    2010-09-01

    The progression of glaucoma can be reduced or delayed by reducing intraocular pressure (IOP). The properties of femtosecond laser surgery, such as markedly reduced collateral tissue damage, coupled with the ability to achieve isolated subsurface surgical effects in the sclera, make this technology a promising candidate in glaucoma management. In this pilot study we demonstrate the in vivo creation of partial thickness subsurface drainage channels with the femtosecond laser in the sclera of rabbit eyes in order to increase aqueous humor (AH) outflow. A femtosecond laser beam tuned to a 1.7 microm wavelength was scanned along a rectangular raster pattern to create the partial thickness subsurface drainage channels in the sclera of one eye of each of the four rabbits included in this pilot study. IOP was measured before and 20 minutes after the laser treatment to evaluate the acute effect of the procedure. OCT images verified the creation of the partial thickness subsurface scleral channels in the eyes of the in vivo rabbits. Comparison of pre- and postoperative IOP measurements in treated and control eyes revealed a reduction in the intraocular pressure due to the increased rate of AH outflow resulted in by the presence of the partial thickness scleral channels. The creation of partial thickness subsurface drainage channels was demonstrated in the sclera of in vivo rabbit eyes with a 1.7 microm wavelength femtosecond laser. Reduction in IOP achieved by the partial thickness channels suggests potential utility in the treatment of elevated IOP. 2010 Wiley-Liss, Inc.

  3. In vivo laser-induced breakdown in the rabbit eye

    NASA Astrophysics Data System (ADS)

    Cain, Clarence P.; DiCarlo, Cheryl D.; Kennedy, Paul K.; Noojin, Gary D.; Amnotte, Rodney E.; Roach, William P.

    1995-05-01

    Threshold measurements for femtosecond laser pulsewidths have been made for retinal minimum visible lesions (MVLs) in Dutch Belted rabbit and rhesus monkey eyes. Laser-induced breakdown (LIB) thresholds in biological materials including vitreous, normal saline, tap water, and ultrapure water have been measured and reported using an artificial eye. We have recorded on video the first LIB causing bubble formation in any eye in vivo using albino rabbit eyes (New Zealand white) with 120- femtosecond (fs) pulses and pulse energies as low as 5 microjoules ((mu) J). These bubbles were clearly formed anterior to the retina within the vitreous humor and, with 60 (mu) J of energy, they lasted for several seconds before disappearing and leaving no apparent damage to the retina. We believe this to be true LIB because of the lack of pigmentation or melanin granules within the albino rabbit eye (thus no absorptive elements) and because of the extremely high peak powers within the 5-(mu) J, 120-fs laser pulse. These high peak powers produce self-focusing of the pulse within the vitreous. The bubble formation at the breakdown site acts as a limiting mechanism for energy transmission and may explain why high-energy femotsecond pulses at energies up to 100 (mu) J sometimes do not cause severe damage in the pigmented rabbit eye. This fact may also explain why it is so difficult to produce hemorrhagic lesions in either the rabbit or primate eye with 100-fs laser pulses.

  4. Fibrinoid reaction after lens extraction in rabbit eyes.

    PubMed

    Ben Simon, Guy J; Kenet, Gili; Spierer, Abraham

    2012-05-01

    To measure the inflammatory reaction in the anterior chamber after lens extraction in a rabbit model and to evaluate the effect of nonsteroidal antiinflammatory drugs (NSAIDs) or steroids on the amount of inflammation as measured by fibrinogen levels in the aqueous humor. Animal laboratory, Goldschleger Research Institute, Tel Aviv University, Sheba Medical Center, Ramat Gan, Israel. Experimental study. Twenty-six eyes of New Zealand white rabbits had lens extraction surgery. One day later, aqueous humor (∼0.1 mL) was withdrawn from the anterior chamber and examined for fibrinogen concentration. Control rabbits received no treatment (9 eyes) or artificial tear eyedrops (5 eyes). One study group received NSAID drops (diclofenac) (6 eyes), and another study group received steroid drops (dexamethasone-neomycin) (6 eyes). All rabbits were treated hourly for 9 applications. Aqueous humor (∼0.1 mL) was withdrawn from the anterior chamber and examined for fibrinogen concentration 1 day later. Fibrinogen levels were also measured in the aqueous in 8 unoperated eyes. Steroid-treated eyes achieved the lowest inflammatory score, followed by NSAID eyes, artificial tears eyes, and untreated eyes. The mean fibrinogen concentrations in the aqueous humor were 69.1 mg% untreated, 52.0 mg% artificial tears, 18.5 mg% NSAIDs, and 2.8 mg% steroids (P=.002). Measurement of aqueous fibrinogen after lens extraction surgery in a rabbit animal model was simple and provided a useful parameter for precise evaluation of postoperative intraocular reaction. Steroids and NSAIDs were effective in reducing postoperative inflammation. Steroids reduced inflammation to almost undetectable values. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  5. Primary Eye Irritation of Guanidine Hydrochloride in Rabbits

    DTIC Science & Technology

    1987-07-01

    Protocol Animals were terminated by intravenous overdose of T- 610 Euthanasia Solution (American Hoechst Corp., Somerville, NJ) and not sodium pentabarbital...Animal eyes were examined 24 hours before dosing using .2% fluorescein dye solution and ultraviolet light (long wave). Justification : Laboratory rabbits

  6. Potential penetration of topical ranibizumab (Lucentis) in the rabbit eye

    PubMed Central

    Chen, J J; Ebmeier, S E; Sutherland, W M; Ghazi, N G

    2011-01-01

    Purpose To assess ranibizumab (Lucentis) penetration into the retina after topical administration in a rabbit model. Methods Ranibizumab was topically applied to the right eye of rabbits according to three regimens: every 2 h (q2hr), four times daily (qid), and twice daily (bid). Intraocular penetration of ranibizumab was assessed at 3, 7, 14, 21, and 28 days following initiation of drops. At each time point, the anterior chambers, vitreous cavities, and blood of one of the rabbits from each subgroup were sampled for ranibizumab detection using enzyme-linked immunosorbent assay (ELISA), and both eyes were then enucleated for ranibizumab detection in the retina by confocal immunohistochemistry (CI). Another group of rabbits received intravitreal ranibizumab and was similarly sampled for comparison. Results CI showed ranibizumab staining in the right retina after 7 and 14 days of q2hr topical administration in two out of four experiments. No ranibizumab was detected in the left retina at any of the sampling time points. ELISA was positive in the vitreous of the right eye at 14 and 21 days in the q2hr treated rabbits in one out of four experiments. No ranibizumab was detected in the qid and bid subgroups. CI and ELISA of the aqueous and vitreous were consistently positive in the intravitreal group. Mild ranibizumab levels were detected in the blood in both the topical and intravitreal groups. Conclusions Topically applied ranibizumab can be detected in the retina following high-frequency administration in a rabbit model. A trans-scleral route of penetration is suggested. PMID:21921952

  7. Glycosaminoglycans in components of the rabbit eye: synthesis and characterization.

    PubMed

    Góes, R M; Laicine, E M; Porcionatto, M A; Bonciani Nader, H; Haddad, A

    1999-08-01

    To trace the eye components involved in proteoglycan synthesis and to characterize the sulfated glycosaminoglycans which are associated to these macromolecules. Sodium [(35)S]-sulfate was injected intravitreally and the rabbits were killed at different time intervals after the injection. The glycosaminoglycans of choroid, ciliary body, cornea, iris, lens capsule, retina and sclera were extracted and processed for estimations of their specific activities, and for electrophoresis plus autoradiography with or without previous treatment with specific enzymes. In addition, methacrylate sections of the eyes were analysed by autoradiography. The peak of specific activities of the glycosaminoglycans of all eye components occurred at 2 days after the intravitreal injection of [( 35)S]-sulfate. The autoradiography of the agarose gels revealed three types of glycosaminoglycans, namely, heparan-, chondroitin- and dermatan sulfate, only in the retina. The other eye components contained heparan sulfate and either chondroitin or dermatan sulfate. Tissue autoradiography together with the biochemical techniques contributed to unravel the origin of the glycosaminoglycans in the eye components. The results of the present investigation have shown that heparan sulfate, contrasting to chondroitin sulfate and dermatan sulfate, is synthesized in all eye components studied and that the glycosaminoglycan composition differs according to the tissue of origin.

  8. Light transmittance of ocular media in living rabbit eyes.

    PubMed

    Algvere, P V; Torstensson, P A; Tengroth, B M

    1993-02-01

    The purpose of this study was to measure the transmittance of electromagnetic radiation, particularly visible light, through the ocular media of living and whole rabbit eyes. Previous determinations have been carried out on excised cadaver eyes. A specially designed fiberoptic probe (outer diameter, 0.9 mm) was placed in the vitreous in front of the retina using a microsurgical technique. In eight living albino rabbits (under general anesthesia), ocular transmittance was determined in the wavelength range 350 to 1100 nm using a reversed beam path (from vitreous to cornea). A maximum optical transmittance of 94% to 96% (standard deviation, 2%-3%) was found between 630 and 730 nm (reflection losses in the cornea-air interface excluded). In the blue portion of the spectrum, transmittance decreased rapidly for shorter wavelengths, and was 50% at 400 nm and less than 1% at 380 nm. In the infrared part of the spectrum, transmittance was close to 90% up to 900 nm but declined at longer wavelengths, coinciding with the absorption in pure water. Calibration recordings showed a 1% to 2% accuracy of the method. This experimental technique using an intraocular fiberoptic probe yields a high accuracy and indicates that light transmittance is very high in vivo and superior to that reported from cadaver eyes.

  9. Computation of temperature elevation in rabbit eye irradiated by 2.45-GHz microwaves with different field configurations.

    PubMed

    Hirata, Akimasa; Watanabe, Soichi; Taki, Masao; Fujiwara, Osamu; Kojima, Masami; Sasaki, Kazuyuki

    2008-02-01

    This study calculated the temperature elevation in the rabbit eye caused by 2.45-GHz near-field exposure systems. First, we calculated specific absorption rate distributions in the eye for different antennas and then compared them with those observed in previous studies. Next, we re-examined the temperature elevation in the rabbit eye due to a horizontally-polarized dipole antenna with a C-shaped director, which was used in a previous study. For our computational results, we found that decisive factors of the SAR distribution in the rabbit eye were the polarization of the electromagnetic wave and antenna aperture. Next, we quantified the eye average specific absorption rate as 67 W kg(-1) for the dipole antenna with an input power density at the eye surface of 150 mW cm(-2), which was specified in the previous work as the minimum cataractogenic power density. The effect of administrating anesthesia on the temperature elevation was 30% or so in the above case. Additionally, the position where maximum temperature in the lens appears is discussed due to different 2.45-GHz microwave systems. That position was found to appear around the posterior of the lens regardless of the exposure condition, which indicates that the original temperature distribution in the eye was the dominant factor.

  10. [Discovery and genetic analysis of blue-eyed mutant in the white rex rabbits].

    PubMed

    Pang, You-Zhi; Xu, Yong-Fei

    2013-06-01

    Using cross, backcross, and full-sib mating experiments, allelism test was conducted to study the genetic mechanism of blue-eyed mutant of the white rex rabbits originated from the F1 generation from the cross American White rex rabbits(♂) × Chinchilla meat rabbits(♀). The study showed that the reason for the blue-eyed mutant of the white rex rabbits was a recessive mutation in Vienna locus. When the V locus was homozygous for the recessive v gene, it was recessive epistatic to other loci (including A, B, C, D, and E), which also controlled the coat color. Regardless of the genotypes in other gene loci, the rabbits appeared blue eyes and white coat color as long as the genotype vv occurred at the Vienna locus. Thus, the combination of genotype vv and genotype rr will produce the blue-eyed and the white rex rabbits. As the blue-eyed mutant of the white rex rabbits is a new finding in China's rabbit breeding program, it is significant to explain the genetic mechanism of the blue-eyed mutant for the breeding and production of rex rabbits.

  11. Posterior Vitreous Detachment With Microplasmin Alters the Retinal Penetration of Intravitreal Bevacizumab (Avastin) in Rabbit Eyes

    PubMed Central

    Goldenberg, David T.; Giblin, Frank J.; Cheng, Mei; Chintala, Shravan K.; Trese, Michael T.; Drenser, Kimberly A.; Ruby, Alan J.

    2010-01-01

    Purpose Intravitreal bevacizumab (Avastin) is frequently used for the treatment of age-related macular degeneration. Previous studies have demonstrated full thickness retinal penetration. Intravitreal recombinant microplasmin (MP) has been shown to successfully induce a posterior vitreous detachment (PVD) and vitreous liquefaction in animals. It has been suggested that a PVD may alter the retinal penetration of molecules in the vitreous cavity. The aim of this study was to compare bevacizumab (BV) retinal penetration in rabbit eyes with and without a MP-induced PVD. Methods Twelve adult rabbits were injected with 0.1 ml (0.4 mg) of MP into the vitreous cavity of one eye. One week later, the rabbits were injected with 0.05 ml (1.25 mg) of BV into both eyes. Both eyes of three rabbits each were harvested at 6, 12, 24, and 72 hours after the BV injection. Frozen retinal cross sections were prepared, and BV retinal penetration was evaluated with immunohistochemistry using a fluorescence-labeled antibody against BV. Two eyes from one rabbit were not injected with either agent and used as controls to compare the background autofluorescence. Peripapillary retinal sections were recorded with a digital camera, and intra-retinal BV fluorescence-labeled antibody was measured by qualitative photographic interpretation. Two additional rabbits received an intravitreal injection of 0.1 ml of MP in one eye. One week later, both eyes from each rabbit were enucleated and frozen retinal sections were prepared and analyzed with light microscopy to evaluate for histologic damage. Results Full thickness BV retinal penetration was observed throughout the retina in both eyes of each rabbit. All of the MP-injected eyes exhibited increased antibody labeling in retinas evaluated 6, 12, and 24 hours after BV injection when compared with the contralateral non-MP-injected eyes. By three days after BV injection, all eyes demonstrated decreased antibody labeling compared to earlier time periods

  12. Correlation study in skin and eye irritation between rabbits and humans based on published literatures.

    PubMed

    Ishii, Satoko; Ishii, Kaori; Nakadate, Masahiro; Yamasaki, Kanji

    2013-05-01

    The purpose of this study was to investigate the correlations in skin and eye irritations between rabbits and humans using published international databases. We selected 60 and 56 compounds for skin and eye irritation, respectively. When the reactions were divided into irritation-negative or irritation-positive, including corrosion, similar reactions between rabbits and humans were detected for 53 compounds in skin irritation and 54 compounds in eye irritation, showing rates of agreement in skin and eye as 88% and 96%, respectively. These findings revealed that correlation in skin and eye irritations between rabbits and humans were high. However, corrosion was observed in rabbit skin treated with 14 compounds, 4 of which showed similar changes in humans, and in rabbit eyes treated with 9 compounds, 1 of which revealed similar changes in humans. These findings indicated that the incidence of corrosion was higher in rabbits than in humans. Our results showed that the data on rabbit irritations in the skin and eye were useful for identifying risk of irritation in human. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Ultraviolet light-induced cyclobutane pyrimidine dimers in rabbit eyes.

    PubMed

    Mallet, Justin D; Rochette, Patrick J

    2011-01-01

    Sunlight exposure of the eye leads to pathologies including photokeratitis, cortical cataracts, pterygium, actinic conjunctivitis and age-related macular degeneration. It is well established that exposure to ultraviolet (UV) radiations leads to DNA damage, mainly cyclobutane pyrimidine dimers (CPDs). CPD formation is the principal factor involved in skin cancer. However, the exact mechanism by which sunlight induces ocular pathologies is not well understood. To shed light on this issue, we quantified the CPD formation onto DNA of rabbit ocular cells following UVB exposure. We found that CPDs were induced only in the structures of the ocular anterior chamber (cornea, iris and lens) and were more concentrated in the corneal epithelium. Residual UVB that pass through the cornea are completely absorbed by the anterior layers of the iris. CPDs were also detected in the central portion of the lens that is not protected by the iris (pupil). By determining the UV-induced DNA damage formation in eyes, we showed that anterior ocular structures are a reliable physical barrier that protects the subjacent structures from the toxic effects of UV. Although the corneal epithelium is the structure where most of the CPDs were detected, no cancer is related to solar exposure. © 2011 The Authors. Photochemistry and Photobiology © 2011 The American Society of Photobiology.

  14. [Eye diseases in dwarf rabbits. 2. Diseases of the cornea, intraocular and retrobulbar disorders, and neoplasms].

    PubMed

    Wagner, F; Heider, H J; Görig, C; Fehr, M

    1998-09-01

    In the second part of this review article the diseases affecting the cornea, intraocular and retrobulbar disorders, and eye-neoplasia of dwarf rabbits are described. These are illustrated by means of selected photographs.

  15. Histopathological Studies on Rabbits Infected by Bacteria Causing Infectious Keratitis in Human through Eye Inoculation

    PubMed Central

    Aldebasi, Yousef H.; Mohamed, Hala A.; Aly, Salah M.

    2014-01-01

    Aim This study aimed to investigate the pathogenic effect of bacteria causing infectious keratitis among patients through experimental study conducted on rabbits’ eyes with the aid of histopathology as eye infection is a common disease in developing countries that may complicate to loss of vision. Methodology 100 swab samples were collected from human infected eyes, at Qassim region during 2012, for the isolation of Pseudomonas aeruginosa and Staphylococcus aureus. The isolated pathogenic bacteria were tested to various antibiotics using some selected antibiotics discs through agar-well diffusion method. Then, experimental study conducted on 27 rabbits. The rabbits were divided randomly into three equal groups, each containing 9 rabbits. Rabbits of group (1) served as control group (Negative Control) and their eyes were inoculated with the buffer only. Rabbits of group (2) were inoculated through eyes with the isolated Pseudomonas aeruginosa. Rabbits of group (3) were inoculated through eyes with the isolated Staphylococcus aureus. Results Out of 100 collected swab samples from human infected eyes, Pseudomonas aeruginosa and Staphylococcus aureus were isolated with a total percentage of 25.21% and 15.65%; respectively and used in this study. Both bacterial isolates were sensitive to Gentamicin and Cefuroxime. Clinically, experimentally infected rabbits by Pseudomonas aeruginosa, revealed varying degree corneal abrasions, corneal abscess and dense corneal opacity. Histopathologically, at 3rd day post-infection (PI), the cornea revealed polymorpho-nuclear cells infiltration with loss of the outer epithelial lining. At 7th day PI, neutrophils were seen in the stroma. At 15th day PI, proliferation of fibroblasts and new vascularisation were seen in the stroma. Clinically, rabbits experimentally infected with Staphylococcus aureus, revealed corneal ulcers and focal abscesses. Histopathologically, at 3rd and 7th day PI, the cornea revealed edema and infiltration of

  16. Functional localization in the rabbit's cerebellar flocculus determined in relationship with eye movements.

    PubMed

    Dufossé, M; Ito, M; Miyashita, Y

    1977-08-01

    In alert albino rabbits, the cerebellar flocculus was mapped for the effect of its local stimulation upon eye movements. Stimulation through a glass pipette electrode placed in a relatively rostral area induced abduction of the ipsilateral eye. That in a relatively caudal area resulted in a downward movement of the ipsilateral eye, accompanied by an upward movement of the contralateral eye. Intorsion of the contralateral eye was also evoked from a relatively dorsal area. These results indicate that Purkinje cells connected with different components of the vestibulo-ocular reflex arc have a differential localization within the flocculus.

  17. Capsular bag opacification after experimental implantation of a new accommodating intraocular lens in rabbit eyes.

    PubMed

    Werner, Liliana; Pandey, Suresh K; Izak, Andrea M; Vargas, Luis G; Trivedi, Rupal H; Apple, David J; Mamalis, Nick

    2004-05-01

    To evaluate the development of capsular bag opacification in rabbit eyes after implantation of an intraocular lens (IOL) designed to minimize contact between the anterior capsule and the IOL and ensure expansion of the capsular bag. David J. Apple, MD Laboratories for Ophthalmic Devices Research, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Ten New Zealand white rabbits had a study IOL (new accommodating silicone IOL [Synchrony, Visiogen, Inc.]) implanted in 1 eye and a control IOL (1-piece plate silicone IOL with large fixation holes) implanted in the other eye. Intraocular lens position, anterior capsule opacification (ACO), and posterior capsule opacification (PCO) were qualitatively assessed using slitlamp retroillumination photographs of the dilated eyes. Anterior capsule opacification and PCO were graded on a 0 to 4 scale after the eyes were enucleated (Miyake-Apple posterior and anterior views after excision of the cornea and iris). The eyes were also evaluated histopathologically. The rate of ACO and PCO was significantly higher in the control group. Fibrosis and ACO were almost absent in the study group; the control group exhibited extensive capsulorhexis contraction, including capsulorhexis occlusion. Postoperative IOL dislocation into the anterior chamber and pupillary block syndrome were observed in some eyes in the study group. The special design features associated with the study IOL appeared to help prevent PCO. Complications in the study group were probably caused by the increased posterior vitreous pressure in rabbit eyes compared to human eyes and the relatively large size of the study IOL relative to the anterior segment of rabbit eyes.

  18. Effect of air bubble on inflammation after cataract surgery in rabbit eyes.

    PubMed

    Demirci, Goktug; Karabas, Levent; Maral, Hale; Ozdek, Sengul; Gülkilik, Gokhan

    2013-07-01

    Intense inflammation after cataract surgery can cause cystoid macular edema, posterior synechia and posterior capsule opacification. This experimental study was performed to investigate the effect of air bubble on inflammation when given to anterior chamber of rabbit eyes after cataract surgery. 30 eyes of 15 rabbits were enrolled in the study. One of the two eyes was in the study group and the other eye was in the control group. After surgery air bubble was given to the anterior chamber of the study group eye and balanced salt solution (BSS; Alcon) was left in the anterior chamber of control eye. On the first, second, fourth and fifth days, anterior chamber inflammations of the eyes were examined by biomicroscopy. On the sixth day anterior chamber fluid samples were taken for evaluation of nitric oxide levels as an inflammation marker. When the two groups were compared, in the air bubble group there was statistically less inflammation was seen. (1, 2, 4. days P = 0,001, and 5. day P = 0,009). These results have shown that when air bubble is left in anterior chamber of rabbits' eyes after cataract surgery, it reduced inflammation. We believe that, air bubble in the anterior chamber may be more beneficial in the cataract surgery of especially pediatric age group, uveitis patients and diabetics where we see higher inflammation. However, greater and long termed experimental and clinical studies are necessary for more accurate findings.

  19. FDTD analysis of temperature elevation in the lens of human and rabbit models due to near-field and far-field exposures at 2.45 GHz.

    PubMed

    Oizumi, Takuya; Laakso, Ilkka; Hirata, Akimasa; Fujiwara, Osamu; Watanabe, Soichi; Taki, Masao; Kojima, Masami; Sasaki, Hiroshi; Sasaki, Kazuyuki

    2013-07-01

    The eye is said to be one of the most sensitive organs to microwave heating. According to previous studies, the possibility of microwave-induced cataract formation has been experimentally investigated in rabbit and monkey eyes, but not for the human eye due to ethical reasons. In the present study, the temperature elevation in the lens, the skin around the eye and the core temperature of numerical human and rabbit models for far-field and near-field exposures at 2.45 GHz are investigated. The temperature elevations in the human and rabbit models were compared with the threshold temperatures for inducing cataracts, thermal pain in the skin and reversible health effects such as heat exhaustion or heat stroke. For plane-wave exposure, the core temperature elevation is shown to be essential both in the human and in the rabbit models as suggested in the international guidelines and standards. For localised exposure of the human eye, the temperature elevation of the skin was essential, and the lens temperature did not reach its threshold for thermal pain. On the other hand, the lens temperature elevation was found to be dominant for the rabbit eye.

  20. Primary dermal and eye irritability tests of hydrophobically modified hydroxypropyl methylcellulose in rabbits.

    PubMed

    Obara, S; Muto, H; Kokubo, H; Ichikawa, N; Kawanabe, M; Tanaka, O

    1992-02-01

    Primary dermal and eye irritation tests of hydrophobically modified hydroxypropyl methylcellulose (HM-HPMC, hydroxypropyl methylcellulose modified with stearylglycidylether), a new cellulose derivative used as a thickener for topical pharmaceuticals and cosmetics, were conducted in rabbits. A dispersion of HM-HPMC (3%) was applied to intact and abraded skins and reactions were observed. A very slight erythema was observed in both skins and this polymer was categorized as a "mild irritant". In the eye irritation test, with a dispersion of the same concentration, it was categorized as "marginal" in unrinsed eyes and "negative" in rinsed eyes.

  1. Ocular biodistribution of bevasiranib following a single intravitreal injection to rabbit eyes

    PubMed Central

    Dejneka, Nadine S.; Wan, Shanhong; Bond, Ottrina S.; Kornbrust, Douglas J.

    2008-01-01

    Purpose The primary objective of these investigations was to determine the ocular biodistribution of bevasiranib, a small interfering RNA (siRNA) targeting vascular endothelial growth factor A (VEGF-A), following a single intravitreal injection to rabbit eyes. Methods A tissue distribution and pharmacokinetic study was conducted with 3H-bevasiranib prepared in balanced-salt solution (BSS). Single doses of either 0.5 mg/eye or 2.0 mg/eye of 3H-bevasiranib were given by intravitreal injection to Dutch-Belted rabbits (both eyes were treated). Subgroups of rabbits were serially-sacrificed at various times up to 7 days following dosing for collection of tissue samples. The right eye of each rabbit was collected whole, and the left eye was dissected to isolate five ocular tissues. All samples were analyzed by liquid scintillation counting to determine the concentrations of bevasiranib equivalents. An ocular disposition study was also performed with non-radiolabeled bevasiranib, which was administered to Dutch-Belted rabbit eyes via intravitreal injection at a dose of 2.0 mg/eye. Twenty-four hours post-dose, the eyes were enucleated and dissected into eight individual ocular structures that were analyzed for intact bevasiranib using a locked nuleic acid (LNA) noncompetitive hybridization-ligation enzyme-linked immunosorbent assay. Results Following intravitreal injection of 0.5 mg or 2.0 mg radiolabeled bevasiranib to Dutch-Belted rabbits, bevasiranib was detected in the vitreous, iris, retina, retinal pigment epithelium (RPE), and sclera (+choroid). As expected, the highest concentrations were found in the vitreous, and vitreous levels steadily decreased over time, while concentrations of radioactivity in the other ocular tissues increased to maximum values between 24 h and 72 h after dosing. Of these tissues, the highest concentration of radioactivity was detected in the retina. The LNA assay further confirmed the presence of intact bevasiranib in these tissues 24 h

  2. Ultrastructural changes to rabbit fibrin and platelets due to aspartame.

    PubMed

    Pretorius, E; Humphries, P

    2007-01-01

    The coagulation process, including thrombin, fibrin, as well as platelets, plays an important role in hemostasis, contributing to the general well-being of humans. Fibrin formation and platelet activation are delicate processes that are under the control of many small physiological events. Any one of these many processes may be influenced or changed by external factors, including pharmaceutical or nutritional products, e.g., the sweetener aspartame (L-aspartyl-L-phenylalanine methyl ester). It is known that phenylalanine is present at position P(9) and aspartate at position P(10) of the alpha-chain of human fibrinogen, and plays an important role in the conversion of fibrinogen to fibrin by the catalyst alpha-thrombin. The authors investigate the effect of aspartame on platelet and fibrin ultrastructure, by using the rabbit animal model and the scanning electron microscope. Animals were exposed to 34 mg/kg of aspartame 26x during a 2-month period. Aspartame-exposed fibrin networks appeared denser, with a thick matted fine fiber network covering thick major fibers. Also, the platelet aggregates appeared more granular than the globular control platelet aggregates. The authors conclude by suggesting that aspartame usage may interfere with the coagulation process and might cause delayed fibrin breakup after clot formation. They suggest this, as the fibrin networks from aspartame-exposed rabbits are more complex and dense, due to the netlike appearance of the minor, thin fibers. Aspartame usage should possibly be limited by people on anti-clotting medicine or those with prone to clot formation.

  3. [Biocompatibility and pharmacokinetics of hydroxypropyl methylcellulose (HPMC) in the anterior chamber of the rabbit eye].

    PubMed

    Ehrich, W; Höh, H; Kreiner, C F

    1990-06-01

    The biocompatibility and pharmacokinetics of hydroxypropylmethylcellulose (HPMC) 2% (Adatocel) and Tylose 2% (MH 1000) were investigated. A modified anterior chamber implantation test on the rabbit eye is suitable for testing both the biocompatibility and the pharmacokinetics of visco-surgical substances. Both substances were well tolerated. From the fourth day onward, HPMC was no longer detectable in the anterior chamber by infrared spectroscopy.

  4. Effect of air bubble on inflammation after cataract surgery in rabbit eyes

    PubMed Central

    Demirci, Goktug; Karabaş, Levent; Maral, Hale; Ozdek, Şengül; Gülkılık, Gökhan

    2013-01-01

    Purpose: Intense inflammation after cataract surgery can cause cystoid macular edema, posterior synechia and posterior capsule opacification. This experimental study was performed to investigate the effect of air bubble on inflammation when given to anterior chamber of rabbit eyes after cataract surgery. Materials and Methods: 30 eyes of 15 rabbits were enrolled in the study. One of the two eyes was in the study group and the other eye was in the control group. After surgery air bubble was given to the anterior chamber of the study group eye and balanced salt solution (BSS; Alcon) was left in the anterior chamber of control eye. Results: On the first, second, fourth and fifth days, anterior chamber inflammations of the eyes were examined by biomicroscopy. On the sixth day anterior chamber fluid samples were taken for evaluation of nitric oxide levels as an inflammation marker. When the two groups were compared, in the air bubble group there was statistically less inflammation was seen. (1, 2, 4. days P = 0,001, and 5. day P = 0,009). Conclusions: These results have shown that when air bubble is left in anterior chamber of rabbits’ eyes after cataract surgery, it reduced inflammation. We believe that, air bubble in the anterior chamber may be more beneficial in the cataract surgery of especially pediatric age group, uveitis patients and diabetics where we see higher inflammation. However, greater and long termed experimental and clinical studies are necessary for more accurate findings. PMID:23571264

  5. Statistical consequences of reducing the number of rabbits utilized in eye irritation testing: data on 67 petrochemicals.

    PubMed

    DeSousa, D J; Rouse, A A; Smolon, W J

    1984-11-01

    Data from 67 six-rabbit eye irritation tests were used to generate two-, three-, and four-rabbit Draize scores. The 15 two-rabbit, 20 three-rabbit, and 15 four-rabbit "subsample" scores for each of the 67 petrochemicals tested were used to establish prediction intervals for the original six-rabbit scores. Prediction interval length shortens with increasing sample size, is widest in the middle portion of the Draize scale, and can be used to select the minimum number of rabbits necessary to satisfy a required level of precision. Also, the ability of each subsample size to correctly classify the test materials according to an in-house irritation classification system was evaluated. Results indicate that subsamples of size 2, 3, 4, and 5 were 88, 93, 95%, and 96% accurate, respectively (compared to six rabbits), at correctly classifying the irritation potential of the materials tested.

  6. Protective effect of 4-coumaric acid from UVB ray damage in the rabbit eye.

    PubMed

    Lodovici, Maura; Caldini, Silvia; Morbidelli, Lucia; Akpan, Victor; Ziche, Marina; Dolara, Piero

    2009-01-08

    UV-induced oxidation damage seems to play a major role in a number of specific pathological conditions of intraocular tissues, such as cataract formation and retinal degeneration. Therefore, antioxidant and/or scavenger compounds might protect the eyes from UV-induced cellular damage. We previously reported that 4-coumaric acid (4-CA) is able to protect rabbit corneal-derived cells (SIRC) from UVB-induced oxidation damage. In this study we evaluated the protective effect of 4-CA against UVB-induced cell damage in rabbit cornea in vivo. Twelve male New Zealand albino rabbits were used; four rabbits were used as a control and received vehicle in one eye and 4-CA acid in the contralateral eye; eight rabbits were exposed to UVB rays (79.2mJ/cm(2)) and three days before to UV exposure each animal received 1 drop/day of vehicle in one eye and 1 drop/day of vehicle containing 4-CA (164ng) in the contralateral eye. Corneal and sclera tissues were removed and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) levels were measured. Superoxide dismutase (SOD) and xanthine oxidase (XO) activities were determined in aqueous humour. UVB-induced vessel hyper-reactivity was strongly reduced at 4 and 24h after UVB exposure after local treatment with 4-CA, 8-oxodGuo levels, a marker of oxidative DNA damage, were significantly increased (P<0.05) in sclera and cornea by UVB irradiation, but when 4-CA was administered to the conjunctiva in a buffered solution once a day for 3d before and 6d after UVB exposure, levels of 8-oxodGuo were similar to controls and significantly reduced (P<0.05) compared to UVB-treated corneas. XO activity in the aqueous humour was significantly increased. The administration of 4-CA for 3d before and 6d after UVB irradiation induced a small but significant (P<0.05) reduction of XO compared with control eyes. Our results indicate that the administration of 4-CA protects eye tissues, thus reducing the harmful effect of UVB radiation at low concentration, probably

  7. Solvent/Detergent Virally Inactivated Serum Eye Drops Restore Healthy Ocular Epithelium in a Rabbit Model of Dry-Eye Syndrome

    PubMed Central

    Tseng, Ching-Li; Chen, Zhi-Yu; Renn, Ting-Yi; Hsiao, Shun-Hung; Burnouf, Thierry

    2016-01-01

    Application of autologous serum eye drops (SEDs) is a recognized means to treat severe dry-eye syndrome (DES). Due to the inconvenience and difficulty of preparing SEDs from some patients, producing SEDs from allogeneic blood donations is gaining popularity. A major safety concern associated with allogeneic blood is virus transmission. We therefore herein evaluated the possibility of applying a solvent/detergent (S/D) treatment to inactivate viruses and studied the impacts of such treatment of SEDs to resolve DES in a rabbit model. Sera prepared from the blood of five rabbits were pooled and divided into two sub-pools. One was untreated (SEDs), while the other was virally-inactivated with 1% Tri-n-butyl phosphate/1% Triton X-45 at 31°C for 1 h (S/D-SEDs). DES was induced in rabbits using 0.1% benzalkonium chloride (BAC). Rabbits were divided into five groups of two rabbits each. One group was untreated (control), three were treated twice daily for 3 weeks using PBS, SEDs, or S/D-SEDs, and the last received an additional 0.1% BAC (as the negative control). The DES condition was determined by measuring aqueous tear secretion (Schirmer’s test), corneal fluorescein staining, a corneal histologic examination, TUNEL stain apoptosis, and corneal inflammatory marker (tumor necrosis factor-α, interleukin (IL)-1β, IL-8, and IL-6) expressions. We first confirmed that SEDs and S/D-SEDs had similar protein profiles and transforming growth factor (TGF)-β contents. Animal experiments showed that tear secretion did not significantly differ between the SED and S/D-SED groups but was significantly higher than in the PBS group. Eye fluorescein staining revealed dramatic improvements in epithelial defects in groups treated with SEDs or S/D-SEDs, and hematoxylin/eosin staining revealed microscopic epithelial layers similar to those of the untreated controls. Inflammatory markers and TUNEL studies showed that healthy epithelium had been restored in groups treated with SEDs or S

  8. Solvent/Detergent Virally Inactivated Serum Eye Drops Restore Healthy Ocular Epithelium in a Rabbit Model of Dry-Eye Syndrome.

    PubMed

    Tseng, Ching-Li; Chen, Zhi-Yu; Renn, Ting-Yi; Hsiao, Shun-Hung; Burnouf, Thierry

    2016-01-01

    Application of autologous serum eye drops (SEDs) is a recognized means to treat severe dry-eye syndrome (DES). Due to the inconvenience and difficulty of preparing SEDs from some patients, producing SEDs from allogeneic blood donations is gaining popularity. A major safety concern associated with allogeneic blood is virus transmission. We therefore herein evaluated the possibility of applying a solvent/detergent (S/D) treatment to inactivate viruses and studied the impacts of such treatment of SEDs to resolve DES in a rabbit model. Sera prepared from the blood of five rabbits were pooled and divided into two sub-pools. One was untreated (SEDs), while the other was virally-inactivated with 1% Tri-n-butyl phosphate/1% Triton X-45 at 31°C for 1 h (S/D-SEDs). DES was induced in rabbits using 0.1% benzalkonium chloride (BAC). Rabbits were divided into five groups of two rabbits each. One group was untreated (control), three were treated twice daily for 3 weeks using PBS, SEDs, or S/D-SEDs, and the last received an additional 0.1% BAC (as the negative control). The DES condition was determined by measuring aqueous tear secretion (Schirmer's test), corneal fluorescein staining, a corneal histologic examination, TUNEL stain apoptosis, and corneal inflammatory marker (tumor necrosis factor-α, interleukin (IL)-1β, IL-8, and IL-6) expressions. We first confirmed that SEDs and S/D-SEDs had similar protein profiles and transforming growth factor (TGF)-β contents. Animal experiments showed that tear secretion did not significantly differ between the SED and S/D-SED groups but was significantly higher than in the PBS group. Eye fluorescein staining revealed dramatic improvements in epithelial defects in groups treated with SEDs or S/D-SEDs, and hematoxylin/eosin staining revealed microscopic epithelial layers similar to those of the untreated controls. Inflammatory markers and TUNEL studies showed that healthy epithelium had been restored in groups treated with SEDs or S

  9. Allergic contact dermatitis due to diclofenac sodium in eye drops.

    PubMed

    Miyazato, Hitona; Yamaguchi, Sayaka; Taira, Kiyohito; Asato, Yutaka; Yamamoto, Yu-Ichi; Hagiwara, Keisuke; Uezato, Hiroshi

    2011-03-01

    Eyelid dermatitis and/or periocular dermatitis (ED/PD) is commonly seen in a variety of skin diseases such as seborrheic dermatitis, atopic dermatitis and psoriasis, but is most often associated with allergic contact dermatitis (ACD). Here, a case of ACD in an 82-year-old man is described; he used 0.1% diclofenac sodium eye drops and exhibited pruritic erythema on the eyelids. Patch test for diclofenac sodium eye drops was positive. Further patch tests revealed a positive reaction to diclofenac sodium (monosodium 2-[2, 6-dichlorophenylamino] phenylacetate), which was the main component in the eye drop medicine. Diclofenac sodium is a non-steroidal anti-inflammatory drug (NSAID), and is frequently used in everyday oral medications, topical ointments, gel agents and eye drops. Case reports on ACD caused by diclofenac sodium eye drops are extremely rare. Nevertheless, it is necessary to consider ACD due to diclofenac sodium when a patient with ED/PD has a history of use of diclofenac sodium eye drops. © 2010 Japanese Dermatological Association.

  10. FIGHTING MULTIPLE DRUG RESISTANCE: EFFECTS OF UV-ACTIVATED CHLORPROMAZINE ON RABBIT'S EYE PSEUDOTUMOURS.

    PubMed

    Pirvulescu, Ruxandra Angela; Cherecheanu, Alina Popa; Romanitan, Mihaela Oana; Dascalu, Ana Maria; Alexandrescu, Cristina

    2015-01-01

    Multiple drug resistance requires a flexible approach to find medicines able to overcome it. One method could be the exposure of existing medicines to UV laser beams to generate active photoproducts against bacteria and/or malignant tumors. The interaction of Chlorpromazine (CPZ) (irradiated with 266 nm pulsed laser beams) was studied at concentrations of 10 mg/ml and 20 mg/ ml in ultrapure water, with pseudotumors of rabbits eyes. The use of CPZ water solution exposed to 266 nm in the treatment of pseudotumor tissues produced on rabbit eyes showed that treatment results depend on initial (before irradiation) CPZ concentration and exposure time. At this stage, one could not specify which out of the generated photoproducts, individual or as a group, was/were efficient in pseudotumor cure but overall effects were observable. Application of CPZ irradiated solutions on rabbit eyes pseudotumors seemed to produce a faster recovery of tissues with respect to control, untreated eyes. Histologic findings in the treated tissues showed a good anti-inflammatory response. The results obtained open perspectives to fight MDR and/or development of pseudotumoral processes with substances that were not initially made for this purpose (non-antibiotics, for instance).

  11. The Isolated Chicken Eye test to replace the Draize test in rabbits.

    PubMed

    Prinsen, Menk K; Hendriksen, Coenraad F M; Krul, Cyrille A M; Woutersen, Ruud A

    2017-04-01

    In 1944, Draize et al., published a paper entitled "Methods for the study of irritation and toxicity of substances applied topically to the skin and mucous membranes". The Organization for Economic Co-operation and Development published their first guideline on eye irritation in 1981, using rabbits. In the early eighties the development of alternative non-animal tests to replace the Draize eye test started. The first attempts to validate alternative tests for eye irritation were considered to be relatively simple by comparing in vitro and in vivo irritation index scores. In the early nineteen-eighties, we introduced the use of isolated eyes as an alternative test for the Draize eye irritation test. What was expected to be a process of several years, however, turned out to be a decades spanning process still not fully completed. For a large part, this can be attributed to the nature of the in vivo test in rabbits, which is more complicated and compromised than originally believed. This paper describes, most chronologically, the development, performance, validation and application of the Isolated Eye Test and, in broader perspective, the international validation and acceptance of this alternative test by regulatory authorities and agencies.

  12. Pharmacokinetics and local safety profile of propranolol eye drops in rabbits.

    PubMed

    Padrini, Letizia; Isacchi, Benedetta; Bilia, Anna Rita; Pini, Alessandro; Lanzi, Cecilia; Masini, Emanuela; Della Bona, Maria Luisa; Calvani, Anna Maria; Ceccantini, Riccardo; la Marca, Giancarlo; Filippi, Luca

    2014-10-01

    Oral propranolol, a nonselective β-blocker, is able to reduce the progression of retinopathy of prematurity in newborns, but it appeared unsafe. This study aimed to find, in rabbits, a propranolol eye drop concentration able to induce lower plasma but higher retinal concentrations than those obtained after oral administration. Male New Zealand white rabbits were treated with oral propranolol (0.25 mg/kg/6 h) for 5 d, and propranolol concentrations were measured after 1, 2, 3, and 6 h in plasma, aqueous humor, vitreous humor, and retina. These concentrations were compared with those obtained after the administration of one drop of 25 μl of propranolol 0.1% prepared in saline, applied every 6 h to both eyes for 5 d. A Draize eye test and histological analyses were performed to assess eye drop tolerability. The administration of eye drops produced retinal concentrations similar to, but plasma concentrations significantly lower than, those measured after oral administration. The local tolerability profile was excellent. Propranolol eye drops are able to ensure high retinal and low plasma concentrations of propranolol, and this finding opens the perspective of possible topical treatment with propranolol in newborns with retinopathy of prematurity.

  13. Assessing ocular irritation potential using a modified ex vivo rabbit eye test.

    PubMed

    Jester, James V; Lam, Larry; Wahlert, Andrew

    2009-01-01

    We have evaluated the ocular irritancy potential of an unknown environmental contaminant, para-toluene sulfonic acid (pTSA), compared with that of known irritants, 5% sodium dodecyl sulfate (SDS) and 10% acetic acid (AA), using a simplified, ex vivo rabbit eye test modified to measure cytotoxicity as a mechanistic correlate to the Draize rabbit eye test. Rabbit eyes were obtained fresh within 24 hours from an abattoir and then exposed to 50 microL of test material. Eyes were then incubated intact for 3 hours or 1 day, and the corneas were removed, stained with calcein acetoxymethylester (AM)/ethidium homodimer (live/dead assay, Invitrogen Corp., Carlsbad, CA, USA), and evaluated by laser scanning confocal microscopy. The number of dead cells was then quantified and the difference was statistically compared. For corneas exposed to 1 ppm and 1% pTSA, there was no significant difference in the number of dead cells compared with water-exposed, control corneas at either 3 hours or 1 day after exposure. However, corneas exposed to 10% and 50% pTSA showed significantly increased (p < .0001) numbers of dead cells, averaging (mean +/- standard deviation) 486 +/- 133 and 1,052 +/- 101 cells/field of view (460 x 460 microm). The level of cytotoxicity was comparable with that observed for 10% AA, which averaged 409 +/- 142 cells/field of view. The data suggest that pTSA is an innocuous irritant at exposure levels environmentally encountered, but that higher concentrations (10% and above) might be considered a slight to mild irritant. We conclude that this modified ex vivo rabbit eye test using the live/dead assay may be a useful model for developing ocular irritation assays.

  14. Short-term ocular toxicity and eye irritation tests following application of sufentanil in rabbits.

    PubMed

    Chen, Hongbin; Chen, Zhenghua; Xu, Ying

    2014-12-01

    To test the safe clinical application of sufentanil as topical ophthalmic drops by examining treated rabbit eyes for ophthalmic irritation signs or short-time toxic reactions. Twenty-four rabbits were randomly divided into 8 groups (n = 3): The ocular toxicity at 14 d after eye drop ad- ministration was evaluated in groups 1 to 4, and at 30 d post- administration in groups 5 to 8. Groups 1 and 5 were treated with blank vehicle and served as normal controls. The left eyes of rabbits in groups 2 and 6 were exposed to low-dose sufentanil.(5 μg, 2 drops within 5 min), groups 3 and 7 received moderate-dose sufentanil (7.5 μg, 3 drops within 10 min), and groups 4 and 8 received high-dose sufentanil.(10 μg, 4 drops within 15 min). As self-controls, the right eyes of each rabbit were administered an equivalent amount of sodium chloride (9 g/L) at the same drop intervals. At 14 and 30 d after exposure to sufentanil, ophthalmic irritation signs were evaluated and corneas were stained with fluorescein and observed by slit-lamp microscopy. Corneal endothelial counts were performed and toxic reactions were evaluated. Multiple parameters were compared in the control and experimental groups by visual inspection and slit-lamp examination at 14 and 30 d after sufentanil administration. No evidence of irritation signs (including corneal opacity, conjunctival congestion, or edema), eye secretions, iris abnormalities, or temporal eye closure were noted. Corneal en- dothelial cell counts did not significantly differ between the control and experimental groups. Light microscopy revealed no pathological or morphological injury to the cornea, conjunctiva, iris, ciliary body, retina, or optic nerve in either group. The same observation outcomes were noted at 14 and 30 d after administration. Single ocular administration of sufentanil at a dose of 5-10 μg in rabbits yields no ocular irritation or toxic responses at 14 or 30 d following eye drop delivery.

  15. Primary Eye Irritation Potential of Nitroguanidine in Rabbits.

    DTIC Science & Technology

    1986-01-09

    dilated vessels within the outer layers of the sclera and the nictitating membrane. No other conjunctival changes were observed. Control Eyes At no time...Grants Management US Army Aeromedical Research Laboratory 4301 Jones Bridge Road Fort Rucker, AL 36362-5000 Bethesda, MD 20814-4799 AIR FORCE Office of...Facilities and Care, Institute of Laboratory Animal Resources , National Research Council. This material has been reviewed by Letterman Army Institute of

  16. Threshold Lesion Temperatures in Laser-Irradiated Rabbit Eyes

    DTIC Science & Technology

    1975-03-31

    laser, tuned to a primary wavelength of 4880A. Pulse length was controlled with an electronic shutter, from Vincent Associates, Model 23XDB2X5...with a narrow beam adapter and 25A Detector Head. Neutral density filters were placed in the laser beam path to control intensity. Laboratory...necessary to control hemorrhaging. Six sutures were placed through the conjunctiva and the eyeholder was sewn onto the front of the eye. A contact

  17. Decrease in corneal damage due to benzalkonium chloride by the addition of sericin into timolol maleate eye drops.

    PubMed

    Nagai, Noriaki; Ito, Yoshimasa; Okamoto, Norio; Shimomura, Yoshikazu

    2013-01-01

    We investigated the protective effects of sericin on corneal damage due to benzalkonium chloride (BAC) used as a preservative in commercially available timolol maleate eye drops using rat debrided corneal epithelium and a human cornea epithelial cell line (HCE-T). Corneal wounds were monitored using a fundus camera TRC-50X equipped with a digital camera; eye drops were instilled into the rat eyes five times a day after corneal epithelial abrasion. The viability of HCE-T cells was calculated by TetraColor One; and Escherichia coli (ATCC 8739) were used to measure antimicrobial activity. The reducing effects on transcorneal penetration and intraocular pressure (IOP) of the eye drops were determined using rabbits. The corneal wound healing rate and rate constants (kH) as well as cell viability were higher following treatment with 0.005% BAC solution containing 0.1% sericin than in the case of treatment with BAC solution alone; the antimicrobial activity was approximately the same for BAC solutions with and without sericin. In addition, the kH for rat eyes instilled with commercially available timolol maleate eye drops containing 0.1% sericin was significantly higher than that of eyes instilled with timolol maleate eye drops without sericin, and the addition of sericin did not affect the corneal penetration or IOP reducing effect of commercially available timolol maleate eye drops. A preservative system comprising BAC and sericin may provide effective therapy for glaucoma patients requiring long-term anti-glaucoma agents.

  18. Neurologic Evaluation of Acute Lacrimomimetic Effect of Cyclosporine in an Experimental Rabbit Dry Eye Model

    PubMed Central

    Toshida, Hiroshi; Nguyen, Doan H.; Beuerman, Roger W.; Murakami, Akira

    2010-01-01

    PURPOSE To evaluate neurologically acute lacrimation caused by cyclosporine (CsA) eyedrops in rabbit. METHODS Normal adult male New Zealand White rabbits and those that underwent parasympathectomy each received a single instillation of 0.1% CsA or vehicle eyedrops. Schirmer tear test (STT) results, flow rate of lacrimal gland (LG) fluid from the excretory lacrimal duct of the main LG, and blink rate (over a 3-minute period) were measured before and after instillation of CsA or vehicle. Light microscopy was performed to examine the main LG in vitro. Protein release from LG fragments was assessed after incubation with CsA for 30 minutes. RESULTS In normal rabbits, the STT value and the flow rate of LG fluid were significantly increased after treatment with CsA compared with vehicle (P < 0.05). In contrast, no changes were found in denervated eyes. The blink rate of CsA-treated eyes was significantly higher than that of vehicle- treated eyes in normal rabbits (P < 0.005), whereas that of denervated eyes decreased significantly after CsA instillation compared with before administration (P < 0.005). Light microscopy showed that the cytoplasm of acinar cells was packed with secretory granules in denervated LG tissue 7 days after parasympathectomy. The same finding was observed 3 hours after CsA instillation. CsA had no stimulatory effect on protein release by acinar cells in LG fragments at all concentrations tested. CONCLUSIONS These results suggest that CsA has no direct effect on tear fluid secretion from the LG in an acute model. Instead, CsA increases reflex tear flow. PMID:19218606

  19. Ciliary body PDT in pigmented rabbit eyes: effect of single and repeated treatment.

    PubMed

    Tsilimbaris, M K; Naoumidi, I I; Kozombolis, V P; Naoumidi, T L; Daskalakis, M; Pallikaris, I G

    2000-06-01

    To investigate the morphologic and hypotensive effect of contact transscleral ciliary body PDT in pigmented rabbit eyes. The right eyes of 33 pigmented rabbits were irradiated using chloraluminum sulfonated phthalocyanine as photosensitizer and a diode laser (670 nm) as the light source. Twenty-five animals received a single treatment. Eight animals received a second treatment 13 days after the first one. Photosensitizer was administered by means of continuous intravenous infusion. Ciliary body was irradiated transsclerally by means of an optic fiber applied on the corneoscleral limbus. In all cases 14-16 laser applications were performed to cover 360 degrees of the ciliary body. Animals were followed for a maximum of 30 days by means of tonometry and biomicroscopy. Retreatments were performed using the same irradiation protocol. At the end of the follow up time animals were sacrificed and their were eyes prepared for light and electron microscopy. Transscleral ciliary body PDT resulted in significant but temporary reduction of IOP in all cases. The effect lasted about two weeks. Retreatment led to a new significant drop of the IOP, which lasted about two weeks again. In histological examination the initial effect was vascular thrombosis, followed by edema and disintegration of the ciliary epithelial layers. In all cases the appearance of the ciliary body had returned to normal 15 days after irradiation. Contact transscleral PDT with the treatment parameters used in this study results in significant but temporary functional and morphological alteration in pigmented rabbits ciliary body.

  20. Evaluation of dermal and eye irritation and skin sensitization due to carbon nanotubes.

    PubMed

    Ema, Makoto; Matsuda, Akitaka; Kobayashi, Norihiro; Naya, Masato; Nakanishi, Junko

    2011-12-01

    The present paper summarizes the results of our studies on dermal and eye irritation and skin sensitization due to carbon nanotubes (CNTs), whose potential applications and uses are wide and varied, including CNT-enhanced plastics, electromagnetic interference/radio-frequency (EMI/RFI) shielding, antistatic material, flexible fibers and advanced polymers, medical and health applications, and scanning probe microscopy. Skin and eyes have the highest risk of exposure to nanomaterials, because deposition of nanomaterials to the surficial organs has the potential to be a major route of exposure during the manufacturing, use, and disposal of nanomaterials. Two products composed of single-walled carbon nanotubes (SWCNTs) and two products composed of multi-walled carbon nanotubes (MWCNTs) were tested regarding acute dermal and acute eye irritation using rabbits, and skin sensitization using guinea pigs. The concentrations of the CNTs in the substances were the maximum allowable for administration. The two products of SWCNTs and one of the products of MWCNTs were not irritants to the skin or eyes. The other product of MWCNTs caused very slight erythema at 24h, but not at 72h, after patch removal in the dermal irritation experiments and conjunctival redness and blood vessel hyperemia at 1h, but not at 24h, in eye irritation experiments. These findings showed that one product of MWCNTs was a very weak acute irritant to the skin and eyes. No products of SWCNTs and MWCNTs exhibited skin-sensitization effects. Our knowledge of the toxicological effects of CNTs is still limited. Further information is needed to clarify the potential for irritation and sensitization given the complex nature of CNTs. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Lens Subluxation after Plasmin and SF6 Injections in Rabbit Eyes

    PubMed Central

    Wu, Wei-Chi; Liu, Chi-Hsien; Wang, Nan-Kai; Chen, Kwan-Jen; Chen, Tun-Lu; Hwang, Yih-Shiou; Liao, Pei-Ju; Li, Lien-Min; Lai, Chi-Chun

    2014-01-01

    Purpose To investigate the rate of lens subluxation following plasmin and/or SF6 injections in eyes, and whether a subsequent elevated level of vascular endothelial growth factor (VEGF) and vitreous tap would aggravate subluxation. Methods Four groups of rabbits were used. Group 1 received an intravitreal injection (IVI) of plasmin and SF6 in the right eye; group 2 received an IVI of plasmin in the right eye; group 3 received an IVI of SF6 in the right eye; and group 4 received an IVI of balanced salt solution in the right eye. After treatment, IVIs of VEGF were given and vitreous tap was performed three times, followed by clinical observation of lens subluxation and scanning electronic microscope evaluation of the zonular fibers. Results After IVIs of plasmin and SF6, and VEGF and vitreous tap had been performed one to three times, lens subluxation was noted in 0%, 43%, 71%, 71%, and 86% of the eyes in group 1. After IVIs of plasmin, VEGF, and vitreous tap had been performed one to three times, lens subluxation was noted in 11%, 22%, 44%, 44%, and 67% of the eyes in group 2. The eyes in group 3 and 4 did not show signs of lens subluxation after VEGF IVIs and vitreous tap. Histology confirmed zonular fiber damage in the eyes treated with plasmin. Conclusions The incidence of lens subluxation increased following plasmin injections in the eyes, and this was aggravated by the subsequent high VEGF level in the eyes and vitreous tapping. Zonular fibers were disrupted following plasmin treatment. These effects should be kept in mind when using plasmin enzymes in patients with vitreoretinal abnormalities. PMID:25397749

  2. Scleral wound healing with cross-link technique using riboflavin and ultraviolet A on rabbit eyes.

    PubMed

    Damasceno, Nadyr A; Miguel, Nadia C; Ventura, Marcelo Palis; Burnier, Miguel; Avila, Marcos P; Damasceno, Eduardo F

    2017-01-01

    The aim of study was to evaluate the cross-link using riboflavin and ultraviolet A (UVA) for improving scleral wound healing. This was an experimental study involving four New Zealand rabbits (eight eyes). Therapy procedure was chosen for the right eye and control procedure for the left one. UVA irradiation of 365 nm with a surface irradiance of 3 mW/cm(2) and a photosensitizer of riboflavin drops were applied for 30 minutes on the right eye at 2 mm from the limbus. Sclerotomy incision was performed at 2 mm from the limbus in both right (on the cross-link-treated area) and left eye. Then, 30 days after surgery, a morphological analysis and histological staining with hematoxylin-eosin and picrosirius red were performed, and the sclerotomy cicatrization of right and left eyes was compared. The variables investigated were as follows: sclerotomy incision pictures and measurements were made using the ImageJ Software. Scleral thickness was measured (employing the anterior optical coherence tomography and the digital caliper). Collagen fiber density stained with picrosirius red staining was measured using the Image Pro Plus software. The morphological analysis showed that in all samples, the right eye presented sclerotomy closure, and in two eyes, among them, there were no visible edges of the sclerotomies incision. The left eye presented sclerotomy closure and incision edges. The Image Pro demonstrated a higher density of collagen fibers in the right eye when compared to the one. The statistical analysis was significant when compared to the collagen fiber density in the treated eyes with the control eyes. The cross-link procedure resulted in a better sclerotomy wound healing.

  3. Scleral wound healing with cross-link technique using riboflavin and ultraviolet A on rabbit eyes

    PubMed Central

    Damasceno, Nadyr A; Miguel, Nadia C; Ventura, Marcelo Palis; Burnier, Miguel; Avila, Marcos P; Damasceno, Eduardo F

    2017-01-01

    Purpose The aim of study was to evaluate the cross-link using riboflavin and ultraviolet A (UVA) for improving scleral wound healing. Materials and methods This was an experimental study involving four New Zealand rabbits (eight eyes). Therapy procedure was chosen for the right eye and control procedure for the left one. UVA irradiation of 365 nm with a surface irradiance of 3 mW/cm2 and a photosensitizer of riboflavin drops were applied for 30 minutes on the right eye at 2 mm from the limbus. Sclerotomy incision was performed at 2 mm from the limbus in both right (on the cross-link-treated area) and left eye. Then, 30 days after surgery, a morphological analysis and histological staining with hematoxylin–eosin and picrosirius red were performed, and the sclerotomy cicatrization of right and left eyes was compared. The variables investigated were as follows: sclerotomy incision pictures and measurements were made using the ImageJ Software. Scleral thickness was measured (employing the anterior optical coherence tomography and the digital caliper). Collagen fiber density stained with picrosirius red staining was measured using the Image Pro Plus software. Results The morphological analysis showed that in all samples, the right eye presented sclerotomy closure, and in two eyes, among them, there were no visible edges of the sclerotomies incision. The left eye presented sclerotomy closure and incision edges. The Image Pro demonstrated a higher density of collagen fibers in the right eye when compared to the one. The statistical analysis was significant when compared to the collagen fiber density in the treated eyes with the control eyes. Conclusion The cross-link procedure resulted in a better sclerotomy wound healing. PMID:28740362

  4. The red eye revisited: ophthalmia nodosa due to tarantula hairs.

    PubMed

    Belyea, D A; Tuman, D C; Ward, T P; Babonis, T R

    1998-06-01

    We present the case of a 17-year-old girl who came to our center with a red irritated eye from exposure to tarantula hairs. An ophthalmology literature search revealed six reported cases. There have been no reports of these cases in the general medical and pediatric literature. Due to the increasing popularity of tarantulas as pets, we present the following case report and discussion to bring attention to this potential complication of tarantula handling.

  5. Ocular Pharmacokinetics of Naringenin Eye Drops Following Topical Administration to Rabbits

    PubMed Central

    Lin, Junli; Sun, Jingjing; Wang, Yandong; Ma, Yan; Chen, Wenpei; Zhang, Ziyang; Gui, Gang

    2015-01-01

    Abstract Purpose: To investigate the ocular pharmacokinetics of 1% naringenin eye drops following topical administration to rabbits. Methods: One drop (50 μL) of 1% naringenin eye drops was instilled into both eyes of each rabbit. The animals were sacrificed at predetermined intervals after dosing, and ocular tissues and plasma were then collected. Concentrations of naringenin were analyzed using specific electrospray ionization liquid chromatography-tandem mass spectrometry method, which is proved to be sensitive, specific, precise, and suitable for determination of naringenin in ocular tissues and plasma of rabbits. Results: Ocular exposure to naringenin, based on AUC(0−t), was highest in cornea, followed by aqueous humor, retina, and vitreous body. The Cmax of naringenin in cornea, aqueous humor, vitreous body, and retina were 67945.30±4109.34 ng/g, 1325.69±239.34, 160.52±38.78 ng/mL, and 1927.08±660.77 ng/g at 0.083, 0.75, 0.083, and 0.083 h after topical administration, respectively. The half-lives for these tissues were 9.37, 0.65, 1.17, and 4.62 h, respectively. There was no significant difference between free naringenin and total naringenin in plasma based on Cmax and Tmax. Cmax of total naringenin in plasma at 0.083 h was 35.12±0.54 ng/mL. Conclusions: Measurable concentrations of naringenin were achieved in ocular tissues after topical application in rabbits. Topical instillation of naringenin may be an effective approach in the treatment of posterior section diseases. PMID:25229266

  6. Effect of leukemia inhibitory factor on corneal nerve regeneration of rabbit eyes after laser in situ keratomileusis.

    PubMed

    Pan, Shuling; Li, Li; Xu, Zhiyong; Zhao, Jiao

    2011-07-20

    To explore the effect of leukemia inhibitory factor on corneal nerve regeneration in a rabbit model after laser in situ keratomileusis. Thirty five healthy New Zealand rabbits were divided into three groups for a 6-month observation, the blank control group, the control group, and the treatment group respectively. Laser in situ keratomileusis for myopia was performed on 30 rabbits (60 eyes in total) and then 1 μg/ml LIF eye drops were used four times a day on the left eyes as the treatment group, and the balanced salt solution (BSS) was used on the right eyes as the control group. Nerve regeneration was evaluated by counting the new regenerated nerves in golden chloride staining. The parameters for dry eye include Schirmer I test and tear break-up time were also examined. The number of regenerated nerve fibers in the treatment group was significantly higher than that in the control group at all time points except the 6th month after LASIK (P<0.05). The parameters for dry eye between two groups were compared at each postoperative time point and the results showed they were significantly higher in the LIF-treated group than in the BSS-control group at 2w, 1m, and 3m respectively. Leukemia inhibitory factor can effectively accelerate the corneal nerve regeneration of rabbit eyes after LASIK surgery and decrease the occurrence of dry eye symptoms. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  7. Structure and function of myelinated nerve fibers in the rabbit eye following ischemia/reperfusion injury.

    PubMed

    Guo, Wenyi; Cringle, Stephen J; Su, Er-Ning; Yu, Paula K; Yu, Xiao-Bo; Sun, Xinghuai; Morgan, William; Yu, Dao-Yi

    2006-02-01

    The rabbit eye presents a valuable model to study the effects of vascular occlusion on the function and structure of myelinated nerve fibers. The rabbit eye has a band of myelinated nerve fibers within the intraocular compartment that are supplied by a narrow band of retinal vasculature. These vessels were transiently occluded ( approximately 8 hours) using laser photocoagulation and the transmission of electrical signals along the nerve fibers was assessed by recording the visual evoked response (VER). Morphological damage was assessed by histological techniques. The ischemic insult produced no permanent change in retinal function as assessed by electroretinography, but the VER was suppressed, indicating failure of nerve fiber transmission. Histologically, the visible damage to the region supported by the retinal vasculature worsened following reperfusion, showing evidence of demyelination and necrosis followed by macrophage responses and gliosis. This rabbit model of ischemia/reperfusion of the retinal vasculature offers a rare opportunity to reliably study the response of myelinated nerve fibers to ischemia/reperfusion insults and has demonstrated the susceptibility of myelinated nerve fibers to such insults.

  8. Numerical solution of ocular fluid dynamics in a rabbit eye: parametric effects.

    PubMed

    Kumar, Satish; Acharya, Sumanta; Beuerman, Roger; Palkama, Arto

    2006-03-01

    Numerical calculations of the aqueous humor dynamics in the anterior chamber of a rabbit's eye are presented to delineate the basic flow mechanisms. The calculations are based on a geometrical model of the eye, which represents the Trabecular meshwork (TM) as a multilayered porous zone of specified pore sizes and void fraction. The outer surface of the cornea is assumed to be at a fixed temperature (corresponding to the ambient temperature), while the iris surface is assumed to be at the core body temperature. Results are obtained for both the horizontal upward-facing orientation of the eye, and the vertical orientation of the eye. Parameters varied include: the temperature difference between the iris and the cornea to underscore the important role of buoyancy in driving the aqueous humor flow; and, the pupil size reflecting different levels of ambient light. Buoyancy is observed to be the dominant driving mechanism for the convective motion in both orientations of the eye. Variations in the pupil size appear to have little influence on the IOP or flow distribution in view of the dominant role of buoyancy in controlling the flow motion. The study provides distributions of the shear stress and flow patterns and delineates the important role of the eye-orientation on these results.

  9. Effects of various eye drops on corneal wound healing after superficial keratectomy in rabbits.

    PubMed

    Tani, Emiko; Katakami, Chikako; Negi, Akira

    2002-01-01

    The effects of various eye drops on corneal wound healing, particularly in the subepithelial haze area, were investigated histologically following superficial keratectomy in rabbits. Mechanical superficial keratectomy was performed in rabbit eyes. Tranilast, betamethasone, hyaluronic acid, and diclofenac eye drops were administered after the procedure. Physiological saline was used as a control. Corneas were excised 1, 2, 3, and 4 weeks after keratectomy, labeled with 3H-thymidine or 3H-proline, and subjected to autoradiography. In the control and diclofenac groups, corneal haze occurred 3 weeks after keratectomy. Histological examination revealed an accumulation of proliferating keratocytes and active synthesis of collagen in the subepithelial area. In the tranilast and betamethasone groups, formation of corneal haze was reduced compared to the controls. The proliferation of keratocytes and the production of collagen in the corneal stroma were inhibited by these drugs. In the hyaluronic acid group also, corneal haze was decreased. In this group, although the proliferation of keratocytes was activated compared to the controls, abnormal accumulation of keratocytes in the subepithelial area was not detected. Tranilast and betamethasone decrease the formation of subepithelial haze by inhibiting keratocyte proliferation and synthesis of extracellular matrix in the corneal stroma. Hyaluronic acid, on the other hand, inhibits subepithelial haze by promoting physiologic wound healing.

  10. A simple method for the subnanomolar quantitation of seven ophthalmic drugs in the rabbit eye.

    PubMed

    Latreille, Pierre-Luc; Banquy, Xavier

    2015-05-01

    This study describes the development and validation of a new liquid chromatography-tandem mass spectrometry (MS/MS) method capable of simultaneous quantitation of seven ophthalmic drugs-pilocarpine, lidocaine, atropine, proparacaine, timolol, prednisolone, and triamcinolone acetonide-within regions of the rabbit eye. The complete validation of the method was performed using an Agilent 1100 series high-performance liquid chromatography system coupled to a 4000 QTRAP MS/MS detector in positive TurboIonSpray mode with pooled drug solutions. The method sensitivity, evaluated by the lower limit of quantitation in two simulated matrices, yielded lower limits of quantitation of 0.25 nmol L(-1) for most of the drugs. The precision in the low, medium, and high ranges of the calibration curves, the freeze-thaw stability over 1 month, the intraday precision, and the interday precision were all within a 15% limit. The method was used to quantitate the different drugs in the cornea, aqueous humor, vitreous humor, and remaining eye tissues of the rabbit eye. It was validated to a concentration of up to 1.36 ng/g in humors and 5.43 ng/g in tissues. The unprecedented low detection limit of the present method and its ease of implementation allow easy, robust, and reliable quantitation of multiple drugs for rapid in vitro and in vivo evaluation of the local pharmacokinetics of these compounds.

  11. Determination of permeability coefficients of ophthalmic drugs through different layers of porcine, rabbit and bovine eyes.

    PubMed

    Loch, Christian; Zakelj, Simon; Kristl, Albin; Nagel, Stefan; Guthoff, Rudolf; Weitschies, Werner; Seidlitz, Anne

    2012-08-30

    To treat ophthalmic diseases like glaucoma or inflammatory disorders topically applied ophthalmic formulations such as eye drops are usually used. In addition, novel ophthalmic implants releasing drug substances locally into different parts of the eye are available today. In the work presented here, the permeability coefficients of selected drugs (ciprofloxacin hydrochloride, lidocaine hydrochloride, timolol maleate) for ophthalmic tissues were determined using side-by-side diffusion chambers (so-called Ussing chambers). Sclera, conjunctiva, cornea, choroidea-retina-complex and a complex of conjunctiva-sclera-choroidea-retina were excised from fresh porcine, rabbit and bovine eyes. In the porcine eye tissues the highest P(app) values were obtained for conjunctiva with the exception of lidocaine. Therefore, it can be estimated that a certain amount of drug diffuses or is transported through conjunctiva after application. The P(app) values for sclera were also higher than those for cornea and even more, the surface area of sclera which is available for drug absorption is much larger than that of cornea when applying an implant. The obtained permeability coefficients for sclera and conjunctiva indicate that the administration of periocular implants can be an alternative to topically applied formulations. The complexes of the tissues were a significantly (p<0.01) stronger barrier to the investigated substances than the separated tissues. Distinct differences in permeability coefficients between the investigated animal tissues were observed. Overall the highest P(app) values for all mounted tissues were obtained with the rabbit, followed by porcine and bovine eyes. Because of these distinct interspecies differences one must be very careful when selecting the proper animal model for the permeability experiments.

  12. Capsaicin pretreatment prevents disruption of the blood-aqueous barrier in the rabbit eye

    SciTech Connect

    Bynke, G.

    1983-06-01

    Capsaicin, the irritating agent of red pepper, produces ocular inflammation through a neurogenic mechanism. The present study is concerned with the long-term effects of capsaicin pretreatment on the capacity of the eye to respond to different inflammatory stimuli. Following retrobulbar injection of capsaicin to rabbits the aqueous flare response induced by subsequent infrared irradiation (IR) of the iris, subcutaneously administered alpha-melanocyte-stimulating hormone (alpha-MSH) and exogenously administered prostaglandin E2 (PGE2) was reduced greatly. In the case of IR and alpha-MSH the reduced responsiveness was manifest for several weeks after capsaicin pretreatment, involving first the capsaicin-treated eye, but later also the contralateral control eye. After 2-3 months the aqueous flare response was normal in both eyes. In the case of PGE2 the responsiveness was reduced for a shorter time; after 3 weeks the response was normal in both eyes. The results indicate that all three stimuli tested are at least partly dependent upon an intact sensory innervation to disrupt the blood-aqueous barrier, but that the mechanism of action of PGE2 is different from that of IR and alpha-MSH.

  13. Sustained Release of an Anti-Glaucoma Drug: Demonstration of Efficacy of a Liposomal Formulation in the Rabbit Eye

    PubMed Central

    Ang, Marcus; Darwitan, Anastasia; Foo, Selin; Zhen, Ma; Koo, Magdalene; Wong, Tina T.; Venkatraman, Subbu S.

    2011-01-01

    Topical medication remains the first line treatment of glaucoma; however, sustained ocular drug delivery via topical administration is difficult to achieve. Most drugs have poor penetration due to the multiple physiological barriers of the eye and are rapidly cleared if applied topically. Currently, daily topical administration for lowering the intra-ocular pressure (IOP), has many limitations, such as poor patient compliance and ocular allergy from repeated drug administration. Poor compliance leads to suboptimal control of IOP and disease progression with eventual blindness. The delivery of drugs in a sustained manner could provide the patient with a more attractive alternative by providing optimal therapeutic dosing, with minimal local toxicity and inconvenience. To investigate this, we incorporated latanoprost into LUVs (large unilamellar vesicles) derived from the liposome of DPPC (di-palmitoyl-phosphatidyl-choline) by the film hydration technique. Relatively high amounts of drug could be incorporated into this vesicle, and the drug resides predominantly in the bilayer. Vesicle stability monitored by size measurement and DSC (differential scanning calorimetry) analysis showed that formulations with a drug/lipid mole ratio of about 10% have good physical stability during storage and release. This formulation demonstrated sustained release of latanoprost in vitro, and then tested for efficacy in 23 rabbits. Subconjunctival injection and topical eye drop administration of the latanoprost/liposomal formulation were compared with conventional daily administration of latanoprost eye drops. The IOP lowering effect with a single subconjunctival injection was shown to be sustained for up to 50 days, and the extent of IOP lowering was comparable to daily eye drop administration. Toxicity and localized inflammation were not observed in any treatment groups. We believe that this is the first demonstration, in vivo, of sustained delivery to the anterior segment of the eye

  14. Scleral cross-linking by riboflavin and blue light application in young rabbits: damage threshold and eye growth inhibition.

    PubMed

    Iseli, Hans Peter; Körber, Nicole; Koch, Christian; Karl, Anett; Penk, Anja; Huster, Daniel; Reichenbach, Andreas; Wiedemann, Peter; Francke, Mike

    2016-01-01

    Scleral cross-linking (SXL) by riboflavin and light application has been introduced as a possible treatment to increase scleral tissue stiffness and to inhibit excessive axial elongation of highly myopic eyes. We evaluated an ocular tissue damage threshold for blue light irradiation, and used SXL treatment to induce eye growth inhibition. The sclera of 3-week-old rabbits (39 pigmented and 15 albino rabbits) were treated with different blue light intensities (450 ± 50 nm) and riboflavin. Alterations and a damage threshold were detected in ocular tissues by means of light microscopy and immunohistochemistry. The influence of SXL on the eye growth was examined in 21 young rabbits and was measured by using A-scan ultrasonography, micrometer caliper, and for selected eyes additionally by MR imaging. Light microscopic examinations demonstrated degenerative changes in ocular tissue after irradiation with blue light intensities above 400 mW/cm(2) (with and without riboflavin application). Therefore, that light intensity was defined as the damage threshold. Tissue alteration in retina, choroid, and sclera and activation of retinal microglia cells and Müller cells could be earlier observed at blue light intensities of 150 and 200 mW/cm(2). Albino rabbits were less sensitive to this SXL treatment. A significant reduction of the eye growth could be detected by SXL treatment with the minimal efficient blue light intensity of 15 mW/cm(2) and maintained stable for 24 weeks. SXL with riboflavin and blue light intensities below a defined damage threshold can induce a long lasting growth inhibitory effect on young rabbit eyes. Therefore, SXL might be a realistic approach to inhibit eye elongation in highly myopic eyes.

  15. Ocular Injury by Transient Formaldehyde Exposure in a Rabbit Eye Model

    PubMed Central

    Lai, Li-Ju; Hsu, Wei-Hsiu; Wu, Albert M.; Wu, June H.

    2013-01-01

    Formaldehyde (FA) is frequently used in sterilizing surgical instruments and materials. Exposure to FA is highly concerned for eye tissues. Rabbit corneal epithelial cells were examined for changes after FA exposure. Our results showed that cell survival decreased 7 days after transient 3 min exposure to more than 100 ppm FA by trypan blue staining while MTT assay detected significant decrease at 20 ppm at 24 hours observation. The decrease of cell survival rate was concentration (up to 600 ppm)- and observation time (1–7 day)- dependent. The cell number decreased after 100 ppm FA exposure for more than 10 min at 7-day observation. The FA treated cells showed increased apoptosis/necrosis and cell cycle accumulation at sub G1 phase as well as mitochondria clustering around nucleus. The in vivo rabbit eye exposure for tear production by Schirmer’s test revealed that the FA-induced overproduction of tear also exhibited observation time (1–10 day)- and FA concentration (20–300 ppm for 5 min exposure)-dependent. Activated extracellular signal-regulated kinase (pERK2) in cornea explants by western blotting was reduced and increased c-Jun amino - terminal kinase (JNK) activation (pJNK) in cornea and conjunctiva was evident at 2 month after exposure to 50–200 ppm FA for 5 min. In conclusion, injury to the eye with transient exposure of up to 100 ppm FA for 3 min decreased corneal cell survival while a more sensitive MTT test detected the cell decrease at 20 ppm FA exposure. Morphology changes can be observed even at 5 ppm FA exposure for 3 min at 7 days after. The FA exposure also increased apoptotic/necrotic cells and sub-G1 phase in cell cycle. Long term effect (2 months after exposure) on the eye tissues even after the removal of FA can be observed with persistent JNK activation in cornea and conjunctiva. PMID:23818956

  16. Effects of argon laser iridotomy on the corneal endothelium of pigmented rabbit eyes.

    PubMed

    Youm, Jie Hyun; Heo, Jeong-Hwa; Kim, Hyo Myung; Song, Jong-Suk

    2014-02-01

    In Asian countries, laser iridotomy for the treatment of angle-closure glaucoma is a common cause of bullous keratopathy, which may be associated with a shallow anterior chamber and dark iris pigmentation in Asians. Several cases of corneal decompensation after argon laser iridotomy have been reported. In the present study, we evaluated the harmful effects of argon laser iridotomy on the corneal endothelium. Argon laser iridotomy was performed on the right eyes of pigmented rabbits. Changes in corneal thickness and endothelial cell density after laser iridotomy were evaluated. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was performed for assessment of corneal endothelial cell apoptosis. Combined staining with alizarin red and trypan blue, as well as a live/dead cell assay, were performed for evaluation of damage to the corneal endothelium induced by laser iridotomy. Corneal thickness did not change immediately after laser iridotomy; however, a significant increase was observed 24 hours after iridotomy (p = 0.001). The endothelial cell density of laser-treated eyes four days after laser iridotomy was significantly decreased compared with control eyes (p < 0.001). TUNEL staining showed many TUNEL-positive cells in the corneal endothelium and corneal stroma. No endothelial trypan blue-stained cell nuclei were observed after laser iridotomy; however, several large endothelial cells with damaged membrane integrity were observed. The live/dead cell assay clearly showed a large number of dead cells stained red in several areas throughout the entire corneal button 24 hours after iridotomy. Argon laser iridotomy induces corneal endothelial cell apoptosis in pigmented rabbit eyes, resulting in decreased endothelial cell density.

  17. Rabbit and Mouse Models of HSV-1 Latency, Reactivation, and Recurrent Eye Diseases

    PubMed Central

    Webre, Jody M.; Hill, James M.; Nolan, Nicole M.; Clement, Christian; McFerrin, Harris E.; Bhattacharjee, Partha S.; Hsia, Victor; Neumann, Donna M.; Foster, Timothy P.; Lukiw, Walter J.; Thompson, Hilary W.

    2012-01-01

    The exact mechanisms of HSV-1 establishment, maintenance, latency, reactivation, and also the courses of recurrent ocular infections remain a mystery. Comprehensive understanding of the HSV-1 disease process could lead to prevention of HSV-1 acute infection, reactivation, and more effective treatments of recurrent ocular disease. Animal models have been used for over sixty years to investigate our concepts and hypotheses of HSV-1 diseases. In this paper we present descriptions and examples of rabbit and mouse eye models of HSV-1 latency, reactivation, and recurrent diseases. We summarize studies in animal models of spontaneous and induced HSV-1 reactivation and recurrent disease. Numerous stimuli that induce reactivation in mice and rabbits are described, as well as factors that inhibit viral reactivation from latency. The key features, advantages, and disadvantages of the mouse and rabbit models in relation to the study of ocular HSV-1 are discussed. This paper is pertinent but not intended to be all inclusive. We will give examples of key papers that have reported novel discoveries related to the review topics. PMID:23091352

  18. Determining the pharmacological activity of Physalis peruviana fruit juice on rabbit eyes and fibroblast primary cultures.

    PubMed

    Pardo, Juan Manuel; Fontanilla, Marta Raquel; Ospina, Luis Fernando; Espinosa, Lady

    2008-07-01

    The pharmacologic activity of compounds isolated from Physalis peruviana has been demonstrated. The use of this fruit juice for treating pterygium has been reported in Colombian traditional medicine. However, studies demonstrating the fruit juice's pharmacologic activity when used in this disease have not been published to date. In the present study the anti-inflammatory and cytostatic activities of P. peruviana fruit juice in a rabbit eye inflammatory model were investigated. A novel rabbit eye inflammation model was developed for studying the juice's anti-inflammatory activity (based on an adaptation of the Draize test). Cytostatic activity was evaluated by measuring and comparing growth rates of cultured fibroblasts exposed and not exposed to various fruit juice concentrations. P. peruviana fruit juice exhibited a mild anti-inflammatory activity compared with methylprednisolone, a known anti-inflammatory drug. An interesting dose-dependent cytostatic effect on cultured fibroblasts was also established. The data found suggest that the P. peruviana fruit juice anti-pterygium effect described in traditional medicine may be related to its inhibiting fibroblast growth. The present study contributes to the pharmacologic knowledge regarding a remedy commonly used in Colombian traditional medicine.

  19. A pilot study: the efficacy of virgin coconut oil as ocular rewetting agent on rabbit eyes.

    PubMed

    Mutalib, Haliza Abdul; Kaur, Sharanjeet; Ghazali, Ahmad Rohi; Chinn Hooi, Ng; Safie, Nor Hasanah

    2015-01-01

    Purpose. An open-label pilot study of virgin coconut oil (VCO) was conducted to determine the safety of the agent as ocular rewetting eye drops on rabbits. Methods. Efficacy of the VCO was assessed by measuring NIBUT, anterior eye assessment, corneal staining, pH, and Schirmer value before instillation and at 30 min, 60 min, and two weeks after instillation. Friedman test was used to analyse any changes in all the measurable variables over the period of time. Results. Only conjunctival redness with instillation of saline agent showed significant difference over the period of time (P < 0.05). However, further statistical analysis had shown no significant difference at 30 min, 60 min, and two weeks compared to initial measurement (P > 0.05). There were no changes in the NIBUT, limbal redness, palpebral conjunctiva redness, corneal staining, pH, and Schirmer value over the period of time for each agent (P > 0.05). Conclusion. VCO acts as safe rewetting eye drops as it has shown no significant difference in the measurable parameter compared to commercial brand eye drops and saline. These study data suggest that VCO is safe to be used as ocular rewetting agent on human being.

  20. A Pilot Study: The Efficacy of Virgin Coconut Oil as Ocular Rewetting Agent on Rabbit Eyes

    PubMed Central

    Mutalib, Haliza Abdul; Kaur, Sharanjeet; Ghazali, Ahmad Rohi; Chinn Hooi, Ng; Safie, Nor Hasanah

    2015-01-01

    Purpose. An open-label pilot study of virgin coconut oil (VCO) was conducted to determine the safety of the agent as ocular rewetting eye drops on rabbits. Methods. Efficacy of the VCO was assessed by measuring NIBUT, anterior eye assessment, corneal staining, pH, and Schirmer value before instillation and at 30 min, 60 min, and two weeks after instillation. Friedman test was used to analyse any changes in all the measurable variables over the period of time. Results. Only conjunctival redness with instillation of saline agent showed significant difference over the period of time (P < 0.05). However, further statistical analysis had shown no significant difference at 30 min, 60 min, and two weeks compared to initial measurement (P > 0.05). There were no changes in the NIBUT, limbal redness, palpebral conjunctiva redness, corneal staining, pH, and Schirmer value over the period of time for each agent (P > 0.05). Conclusion. VCO acts as safe rewetting eye drops as it has shown no significant difference in the measurable parameter compared to commercial brand eye drops and saline. These study data suggest that VCO is safe to be used as ocular rewetting agent on human being. PMID:25802534

  1. Biodegradable PTLGA Terpolymers versus Collagen Implants Used as an Adjuvant in Trabeculectomy in Rabbit Eye.

    PubMed

    Niu, Weiran; Shen, Guanglin; Yuan, Yuanzhi; Ma, Xiaoping; Li, Suming; Wang, Jingzhao; Fan, Zhongyong; Liao, Lan

    2015-01-01

    Purpose. To evaluate the effectiveness and safety of three biodegradable terpolymers prepared from L-lactide, trimethylene carbonate, and glycolide (PTLGA) as an aid for trabeculectomy compared with the Ologen (OLO). Methods. Trabeculectomy was carried out on rabbits with implantation made from OLO or three PTLGA terpolymers. Intraocular pressure (IOP) was recorded 1, 2, 3, and 6 months postoperatively and bleb evaluations were performed using ultrasound biomicroscopy (UBM) 3 months after surgery, optical coherence tomography (OCT) every month, and transmission electron microscopy (TEM) six months after surgery followed by histological examination 1, 2, 3, and 6 months postoperatively. Result. IOP was significantly reduced in all groups after surgery. There were no significant differences in the IOL between groups at any time after implantation. There was no significant difference between the groups examined by OCT, UBM, and TEM. Exposure of the implant was observed in one eye from the OLO group and one eye in the P1. Subconjunctiva hyperblastosis was observed in one eye from group P3 and two eyes from the OLO group. Conclusions. Subconjunctival implantation of filtering devices made from PTLGA may present a safe and effective additional surgical tool for the treatment of filtering surgery. Fewer complications were observed in the group with P2 implants compared to other groups.

  2. Testing toxicity of multiple intravitreal injections of bevacizumab in rabbit eyes.

    PubMed

    Xu, Weiqi; Wang, Hong; Wang, Fenghua; Jiang, Yuan; Zhang, Xian; Wang, Wenqiu; Qian, Jin; Xu, Xun; Sun, Xiaodong

    2010-08-01

    To evaluate the potential toxicity of repeated intravitreal injections of bevacizumab in rabbit eyes. Randomized, placebo-controlled experimental animal study. Fourteen chinchilla rabbits; 12 assigned to the experimental group and 2 assigned to the normal control group. Three sequential, biweekly, intravitreal injections of bevacizumab in doses of 2.5 mg/0.1 mL or 5.0 mg/0.2 mL were performed on each rabbit. Evaluations included intraocular pressure (IOP), aqueous flare, B-scan ultrasound, fundus photography, ultrasound biomicroscopy, electroretinography (ERG), and visually evoked potentials (VEPs) performed at baseline and during the follow-up period. The eyes were enucleated at 1 week and 4 weeks after the last intravitreal injection, and underwent light and electron microscopic evaluations, as well as testing for apoptotic activity. After intravitreal injections, no changes were found by regular clinical observation and IOP tests. There was no significant difference in the anterior chamber inflammatory activity evaluated by the laser flare meter. No evidence of retinal toxicity was seen after intravitreal bevacizumab at doses of 2.5 and 5.0 mg by either ERG or flash VEPs. Electron microscopy did show the presence of inflammatory cells and some ultrastructural changes in the photoreceptor cells in the 5.0 mg experimental group 1 week after the third injection. Mild to moderate apoptosis of photoreceptors was detected in the 5.0 mg group at the same time. The biweekly, multiple intravitreal injections of bevacizumab did not result in evidence of toxicity in regular clinical and functional observations at both 2.5 mg and 5.0 mg doses. The 5.0 mg dose may induce transient inflammation, ultrastructural abnormalities, and apoptosis.

  3. [The study of cyclosporin A modified intraocular lens preventing posterior capsular opacification in rabbit eyes].

    PubMed

    Teng, H; Zhang, H; Tian, F; Gu, H Q; Liu, X; Sun, J

    2016-02-01

    To investigate the safety and efficacy of cyclosporine A sustained release from modified intraocular lens for preventing posterior capsular opacification (PCO) in rabbit eyes. Forty-five New Zealand albino rabbits undergoing phacoemulsification in their right eyes were randomly and equally divided into three groups. Group A had implanted original IOL, group B had implanted PLGA-IOL(IOL coated with polylactide-glycoli acid), and group C had implanted CsA-PLGA-IOL (CsA loaded PLGA-IOL). All the 45 eyes were examined by a slit-lamp microscope. The intraocular pressures were recorded. Anterior chamber flare and aqueous humor cells were graded at different time point after surgery. The concentrations of CsA in the aqueous humor and blood were determined by high performance liquid chromatography. Anterior segment tissue was histologically examined. Wet posterior capsules were weighed. PCO was graded 6 months later. The mean concentrations of CsA in group C at 2 h,1 d,3 d,7 d,14 d,30 d,60 d after operation were (11.47±2.42) mg/L, (10.30±2.15) mg/L, (6.71±1.45) mg/L, (4.81±1.16) mg/L, (6.11±0.84) mg/L, (2.53±0.77) mg/L, (0.86±0.28) mg/L. The concentrations of CsA in blood were undetectable. During the early days after operation, the reactions of the anterior chamber in group A and B were more severe than group C. The initial appearance of PCO in group C was much later than in the other two groups, and the grade of PCO in group C was much lower than the other two groups. The mean weights of wet posterior capsules in group A(312.86±52.91) mg and B(310.64±62.42) mg were much heavier than that of group C(56.93 ± 24.24) mg. Histological observation showed that there was remarkably less accumulation of lens materials on the posterior capsules in group C than in the other two groups. No toxic actions were found in intraocular tissues in group C. Our study suggested that Cyclosporin A modified intraocular lens could effectively and safely prevent the formation and

  4. Efficient vitreolysis by combining plasmin and sulfur hexafluoride injection in a preclinical study in rabbit eyes

    PubMed Central

    Wu, Wei-Chi; Liu, Chi-Hsien; Chen, Chih-Chun; Wang, Nan-Kai; Chen, Kwan-Jen; Chen, Tun-Lu; Hwang, Yih-Shiou; Li, Lien-Min

    2012-01-01

    Purpose To investigate the efficacy of plasmin and sulfur hexafluoride (SF6) on the vitreoretinal junction, as well as the long-term safety in the eye and effect on the recipient’s general health after application in the eye. Methods The study design included four groups of rabbits with three animals in each group. Group 1 received an intravitreal injection (IVI) of plasmin and SF6 in the right eye; group 2 received an IVI of plasmin in the right eye; group 3 received an IVI of SF6 in the right eye; and group 4 received an IVI of balanced salt solution in the right eye, which served as a normal control. Long-term safety (up to approximately three months) after plasmin and/or SF6 injection was evaluated morphologically by clinical examination, histology, and immunohistochemistry, and functionally by electroretinograms (ERGs). General health evaluations after intravitreal injection included the assessment of weight gain, food intake, body temperature, and complete blood count analysis. Results Plasmin plus SF6 injection resulted in complete posterior vitreous detachment (PVD), whereas plasmin or SF6 injection alone resulted in only partial PVD. Balanced salt solution did not induce PVD. Eighty days after intravitreal injection, there were no major differences among the eyes of the three groups of animals compared with the normal control animals upon clinical evaluation, or regarding retinal morphology and ERGs. The lenses examined remained clear for up to 80 days following the intravitreal injection of plasmin plus SF6, except one eye in the plasmin-treated group. ERGs decreased transiently one week after intravitreal injection in groups 1 through 3, but animals recovered fully to normal status afterward. General health was not affected after the injection of plasmin plus SF6. Conclusions Efficient vitreoretinal separation could be achieved, and an acceptable long-term safety profile was noted after plasmin plus SF6 injection in the eye. No major ocular toxicity or

  5. In vitro eye irritancy test of lauryl derivatives using the reconstructed rabbit corneal epithelium model.

    PubMed

    Matsuda, Sanae; Hisama, Masayoshi; Shibayama, Hiroharu; Itou, Norihiko; Iwaki, Masahiro

    2009-06-01

    The rabbit corneal epithelium model (RCE model) was developed as a three-dimensional in vitro model to replace animal testing for the assessment of eye tolerance. In the model, a stratified culture of rabbit corneal epithelial cells is grown at the air-liquid interface on an amniotic membrane acting as a parabasal membrane. The alkaline exposure was restored each day in the presence of no irritants, although with the addition of SLS, which is a major irritant, the restoration of deficit was inhibited on the RCE model in a dose-dependent manner. The results of this test were comparable with those of the Draize test, and thus, this method using the RCE model may prove to be a useful and sensitive in vitro eye irritation test. The lauryl fatty chain derivatives, such as polyoxyethylene (9) lauryl ether (PLE), sodium polyoxyethylene (2) lauryl ether sulfate (SPLE), mono glyceryl laurate (MGL), and sodium N-lauroyl-l-glutaminate (SLG), which are widely used as surfactants for toiletry products and cosmetics, were evaluated for in vitro eye irritation potential using the RCE model. SLS, PLE, SPLE, MGL, and SLG inhibited 88.7%, 59.2%, 69.0%, 47.5%, and 15.7% of the restoration of deletion 24h after treatment at a concentration of 0.05%. The IC(50) (50% inhibitory concentration) values of SLS, PLE, SPLE, MGL, and SLG were 0.002%, 0.021%, 0.005%, 0.056%, and 0.448%, respectively. These results indicated that a functional group at the end of lauryl chain is an important factor for inhibiting the restoration of deletion using the RCE model.

  6. Comparison of systemic absorption between ofloxacin ophthalmic in situ gels and ofloxacin conventional ophthalmic solutions administration to rabbit eyes by HPLC-MS/MS.

    PubMed

    Li, Jiawei; Zhao, Hainan; Okeke, Chukwunweike Ikechukwu; Li, Lin; Liu, Zhidong; Yin, Zhongpeng; Zhuang, Pengwei; Sun, Jingtong; Wu, Tao; Wang, Meng; Li, Nan; Pi, Jiaxin; Zhang, Qian; Zhang, Rui; Ma, Li; Pang, Xiaochen; Liu, Zhanbiao; Zhang, Li; Fan, Lili

    2013-06-25

    In recent years, many pharmaceutical scientists have focused on developing the in situ gel-forming systems to overcome the poor bioavailability and therapeutic response exhibited by conventional ophthalmic solutions due to rapid pre-corneal elimination of the drug. The present work was to compare the systemic absorptions of ophthalmic ofloxacin in situ gel with the conventional ofloxacin eye drop after topical instillation to rabbit eyes by HPLC-MS/MS method and also determine the relative contribution of the nasal and the conjunctival mucosae to systemic ofloxacin absorption following topical instillation. The systemic AUC, Cmax, Tmax and Ke for ophthalmic in situ gel and ophthalmic solution after ocular instillation were 202.63±118.85 and 202.25±57.74 ng mL(-1) h, 54.22±28.31 and 48.4±25.97 ng mL(-1), 1.08±0.20 and 1.25±0.88 h, 0.0576±0.0207 and 0.0388±0.0248, respectively. And the values for the ratios of the AUC of anterior chamber of rabbit eye to blood plasma, AUCac/AUCpl, for ofloxacin conventional eye drop and in situ gel were 0.25 and 0.52, respectively. Statistic results showed that there was no significant difference in systemic absorption between the test groups and the reference groups (P>0.05) as both formulations have an AUCsa/AUCpl of 0.35. Therefore, the ophthalmic in situ gel may not decrease the drugs systemic absorption when administered in an equivalent dose as ophthalmic solutions into the rabbit eyes.

  7. Eye-blink conditioning is associated with changes in synaptic ultrastructure in the rabbit interpositus nuclei

    PubMed Central

    Weeks, Andrew C.W.; Connor, Steve; Hinchcliff, Richard; LeBoutillier, Janelle C.; Thompson, Richard F.; Petit, Ted L.

    2007-01-01

    Eye-blink conditioning involves the pairing of a conditioned stimulus (usually a tone) to an unconditioned stimulus (air puff), and it is well established that an intact cerebellum and interpositus nucleus, in particular, are required for this form of classical conditioning. Changes in synaptic number or structure have long been proposed as a mechanism that may underlie learning and memory, but localizing these changes has been difficult. Thus, the current experiment took advantage of the large amount of research conducted on the neural circuitry that supports eye-blink conditioning by examining synaptic changes in the rabbit interpositus nucleus. Synaptic quantifications included total number of synapses per neuron, numbers of excitatory versus inhibitory synapses, synaptic curvature, synaptic perforations, and the maximum length of the synapses. No overall changes in synaptic number, shape, or perforations were observed. There was, however, a significant increase in the length of excitatory synapses in the conditioned animals. This increase in synaptic length was particularly evident in the concave-shaped synapses. These results, together with previous findings, begin to describe a sequence of synaptic change in the interpositus nuclei following eye-blink conditioning that would appear to begin with structural change and end with an increase in synaptic number. PMID:17551096

  8. Eye-blink conditioning is associated with changes in synaptic ultrastructure in the rabbit interpositus nuclei.

    PubMed

    Weeks, Andrew C W; Connor, Steve; Hinchcliff, Richard; LeBoutillier, Janelle C; Thompson, Richard F; Petit, Ted L

    2007-06-01

    Eye-blink conditioning involves the pairing of a conditioned stimulus (usually a tone) to an unconditioned stimulus (air puff), and it is well established that an intact cerebellum and interpositus nucleus, in particular, are required for this form of classical conditioning. Changes in synaptic number or structure have long been proposed as a mechanism that may underlie learning and memory, but localizing these changes has been difficult. Thus, the current experiment took advantage of the large amount of research conducted on the neural circuitry that supports eye-blink conditioning by examining synaptic changes in the rabbit interpositus nucleus. Synaptic quantifications included total number of synapses per neuron, numbers of excitatory versus inhibitory synapses, synaptic curvature, synaptic perforations, and the maximum length of the synapses. No overall changes in synaptic number, shape, or perforations were observed. There was, however, a significant increase in the length of excitatory synapses in the conditioned animals. This increase in synaptic length was particularly evident in the concave-shaped synapses. These results, together with previous findings, begin to describe a sequence of synaptic change in the interpositus nuclei following eye-blink conditioning that would appear to begin with structural change and end with an increase in synaptic number.

  9. Therapeutic efficacy of fibroblast growth factor 10 in a rabbit model of dry eye.

    PubMed

    Zheng, Wenjing; Ma, Mingming; Du, Ergang; Zhang, Zhengwei; Jiang, Kelimu; Gu, Qing; Ke, Bilian

    2015-11-01

    The aim of the present study was to investigate the therapeutic efficacy of fibroblast growth factor 10 (FGF10) in the promotion of healing, survival and expression of mucin in corneal epithelial cells in a rabbit dry eye model. A total of 12 healthy female New Zealand white rabbits were divided randomly into three groups. The lacrimal glands were injected with saline either alone (normal control group) or with concanavalin A (Con A), with either topical phosphate‑buffered saline (PBS; PBS control group) or 25 µg/ml FGF10 (FGF10 treatment group). Lacrimal gland inflammation, tear function, corneal epithelial cell integrity, cell apoptosis and mucin expression were subsequently assessed. Lacrimal gland tissue biopsies were performed in conjunction with histology and electron microscopy observations. Tear meniscus height (TMH) and tear meniscus area (TMA) were measured using Fourier domain‑optical coherence tomography. Tear membrane break‑up time (TBUT) was also assessed and corneal fluorescein staining was performed. The percentages of apoptotic corneal and conjunctival (Cj) epithelial cells (ECs) were counted using a terminal deoxynucleotidyl transferase‑mediated dUTP nick end labeling method. The mRNA expression levels of Muc1 were determined using reverse transcription‑quantitative polymerase chain reaction analyses. The TMH and TMA values of the PBS and treatment groups were found to be significantly reduced, compared with those of the normal control group 3 days after Con A injection. However, the TMH and TMA of the FGF10 treatment group were higher, compared with those of the PBS group 3 and 7 days after treatment, respectively. Furthermore, the FGF10 treatment group exhibited prolonged TBUT, reduced corneal fluorescein staining and repaired epithelial cell ultrastructure7 days after treatment. The percentages of apoptotic corneal‑ and Cj‑ECs in the FGF10 treatment group were significantly reduced, compared with those in the PBS group. FGF10

  10. Anti-inflammatory and antioxidant effects of Tualang honey in alkali injury on the eyes of rabbits: Experimental animal study

    PubMed Central

    2011-01-01

    Background Alkali injury is one of the most devastating injuries to the eye. It results in permanent unilateral or bilateral visual impairment. Chemical eye injury is accompanied by an increase in the oxidative stress. Anti-inflammatory and antioxidant agents play a major role in the treatment of chemical eye injuries. The purpose of this study is to evaluate the anti-inflammatory (clinical and histopathological) and antioxidant effects of Tualang honey versus conventional treatment in alkali injury on the eyes of rabbits. Methods A preliminary study was carried out prior to the actual study to establish the alkali chemical injury on rabbit's cornea and we found that alkali chemical injury with 2 N NaOH showed severe clinical inflammatory features. In actual study, alkali injury with 2 N NaOH was induced in the right eye of 10 New Zealand White rabbits' cornea. The rabbits were divided into two groups, Group A was given conventional treatment and Group B was treated with both topical and oral Tualang honey. Clinical inflammatory features of the right eye were recorded at 12 hours, 24 hours, 72 hours, 5th day and 7th day post induction of alkali burn on the cornea. The histopathological inflammatory features of the right corneas of all rabbits were also evaluated on day-7. The level of total antioxidant status and lipid peroxidation products in the aqueous humour, vitreous humour and serum at day-7 were estimated biochemically. Fisher's Exact, Chi-Square and Mann-Whitney test were used to analyse the data. Results There was no statistically significant difference in clinical inflammatory features (p > 0.05) between honey treated and the conventional treated group at different times of examination. Histopathological examination of the cornea showed the number of polymorphonuclear leucocytes was below 50 for both groups (mild grade). There was also no significant difference in the level of total antioxidant status as well as lipid peroxidation products in aqueous

  11. Ultrasound-mediated transscleral delivery of macromolecules to the posterior segment of rabbit eye in vivo.

    PubMed

    Suen, Wai-Leung Langston; Wong, Hoi Sang; Yu, Yu; Lau, Laurence Chi Ming; Lo, Amy Cheuk-Yin; Chau, Ying

    2013-06-26

    This study aims to determine the in vivo effectiveness of low-frequency ultrasound in mediating the transport of macromolecules to the posterior segment of the eye via transscleral route. It investigates if damage is caused by ultrasound at the tested operation parameters on the posterior ocular tissues and visual function. Ultrasound (I(SATA) = 0.12 W/cm(2), center frequency = 40 kHz, 90-second continuous wave) was applied on the sclera of New Zealand white rabbits for one to three cycles. Solution of fluorescent dextran (70 kDa) was placed above sclera during and after ultrasound application to assess transscleral transport of macromolecules. Amount of dextran delivered to vitreous was determined by detection of fluorescence. Visual function of ultrasound-treated rabbits was examined by full-field electroretinography (ffERG). The effect of ultrasound on ocular tissue structures was examined by binocular indirect ophthalmoscope (BIO) and histology. Repeated ultrasound resulted in increasing concentration of dextran, which was otherwise undetectable in the vitreous. Transscleral barrier against dextran transport was restored to original value at 2 weeks postultrasound treatment. Studies from ffERG suggested that electric responses from neural transmission of retinal cells are normal at 1 day, 7 days, and 14 days after ultrasound applications. BIO and histology revealed no structural abnormality in posterior ocular tissues after ultrasound treatment. Low-frequency ultrasound significantly enhanced the penetration of macromolecules via transscleral route. No undesirable side effects have been found for up to 2 weeks after ultrasound application. The study supports that sonication is a potentially safe and effective method to modulate transscleral barriers for delivering macromolecular therapeutics to posterior segment of the eye.

  12. Long-term exposure of the rabbit eye to silicone oil causes optic nerve atrophy.

    PubMed

    Papp, András; Kiss, Evelyn B; Tímár, Orsi; Szabó, Eszter; Berecki, Arpád; Tóth, Jeannette; Páli, Jeno

    2007-09-14

    A silicone oil endotamponade following vitrectomy has for decades been a standard method in human ophthalmology with a view to restoring a detached retina. However, severe functional deficiencies may remain after treatment. In adult rabbits, the injection of silicone oil into the eye-ball following vitrectomy resulted in a decrease of 89% in the number of myelinated optic nerve fibres after a survival time of 1 year (418,313+/-29,703 versus 45,620+/-23,905). Concomitantly, the cross-sectional area of the optic nerve was also reduced significantly (0.853+/-0.159 mm2 versus 0.355+/-0.107 mm2). The number of non-neuronal elements of the optic nerve remained virtually unchanged immediately behind the eye-ball and in the middle part of the nerve, whereas it increased significantly close to the optic chiasm (3040+/-433 versus 3888+/-403). Thus, destruction of the myelinated optic nerve fibres is likely to be responsible for the functional deficiencies observed after silicone oil implantation.

  13. Corneal permeability assay of topical eye drop solutions in rabbits by MRI.

    PubMed

    Mao, Xiaochun; Zhang, Shaowei; Hen, Hui; Du, Longting; Li, Guigang; Li, Bin; Zhang, Hong

    2010-12-01

    This study examined the corneal permeability of topical eye drop solutions added with various corneal penetrating accelerators and gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) by nuclear magnetic resonance imaging (MRI). Twenty-four New Zealand rabbits were randomly divided into 3 groups according to the random digits table: Gd-DTPA group, in which the rabbits received 23.45% Gd-DTPA; hyaluronic acid group, in which 23.45% Gd-DTPA plus 0.2% hyaluronic acid was administered; azone group, in which 23.45% Gd-DTPA with 0.2% azone was given. Fifty microliters of the eye drops was instilled into the conjunctive sac every 5 min, for a total of 6 applications in each group. Contrast medium signals in the cornea, anterior chamber, posterior chamber, and vitreous body were scanned successively by MRI. The morphology and cell density of the corneal endothelium were examined before and 24 h after the treatment. The results showed that the residence time of Gd-DTPA in the conjunctival sac in the hyaluronic acid and azone groups was longer than that in the Gd-DTPA group. The signals in the anterior chamber of the Gd-DTPA and hyaluronic acid groups were increased slightly, and those in the azone group strengthened sharply. The signal intensity continuously rose over 80 min before reaching plateau. The strengthening rate of signals in the anterior chamber was 19.63% in the Gd-DTPA group, 53.42% in the sodium hyaluronate group, and 226.94% in the azone group. No signal was detected in the posterior chamber or vitreous body in all the 3 groups. Corneal morphology and cell density did not show any significant changes after the treatment in all the 3 groups. It was concluded that azone can significantly improve the corneal permeability of drugs that are similar to Gd-DTPA in molecular weight and molecular size, and MRI is a noninvasive technique that can dynamically detect eye drop metabolism in real time.

  14. Research on the Stability of a Rabbit Dry Eye Model Induced by Topical Application of the Preservative Benzalkonium Chloride

    PubMed Central

    Luan, Shaohong; Wan, Pengxia; Li, Naiyang; Tang, Jing; Han, Yu; Xiong, Cuiju; Wang, Zhichong

    2012-01-01

    Background Dry eye is a common disease worldwide, and animal models are critical for the study of it. At present, there is no research about the stability of the extant animal models, which may have negative implications for previous dry eye studies. In this study, we observed the stability of a rabbit dry eye model induced by the topical benzalkonium chloride (BAC) and determined the valid time of this model. Methods and Findings Eighty white rabbits were randomly divided into four groups. One eye from each rabbit was randomly chosen to receive topical 0.1% BAC twice daily for 2 weeks (Group BAC-W2), 3 weeks (Group BAC-W3), 4 weeks (Group BAC-W4), or 5 weeks (Group BAC-W5). Fluorescein staining, Schirmer's tests, and conjunctival impression cytology were performed before BAC treatment (normal) and on days 0, 7, 14 and 21 after BAC removal. The eyeballs were collected at these time points for immunofluorescence staining, hematoxylin and eosin (HE) staining, and electron microscopy. After removing BAC, the signs of dry eye in Group BAC-W2 lasted one week. Compared with normal, there were still significant differences in the results of Schirmer's tests and fluorescein staining in Groups BAC-W3 and BAC-W4 on day 7 (P<0.05) and in Group BAC-W5 on day 14 (P<0.05). Decreases in goblet cell density remained stable in the three experimental groups at all time points (P<0.001). Decreased levels of mucin-5 subtype AC (MUC5AC), along with histopathological and ultrastructural disorders of the cornea and conjunctiva could be observed in Group BAC-W4 and particularly in Group BAC-W5 until day 21. Conclusions A stable rabbit dry eye model was induced by topical 0.1% BAC for 5 weeks, and after BAC removal, the signs of dry eye were sustained for 2 weeks (for the mixed type of dry eye) or for at least 3 weeks (for mucin-deficient dry eye). PMID:22438984

  15. Fatal necrotising enterocolitis due to mydriatic eye drops.

    PubMed

    Ozgun, Uygur; Demet, Terek; Ozge, Koroglu A; Zafer, Dokumcu; Murat, Sezak; Mehmet, Yalaz; Nilgun, Kultursay

    2014-05-01

    Retinopathy of prematurity (ROP) is a serious problem of preterm infants which may lead to impairment of vision and even to blindness if untreated. Routine eye examination is necessary for early diagnosis and treatment of ROP in preterm infants. Mydriatic eye drops (cyclopentolate, tropicamide and phenylephrine) are applied before the ophthalmic examination. These agents are rarely absorbed to systemic circulation and in some cases result with serious side effects like skin rash, tachycardia, feeding intolerance, discomfort, apnea, gastric dilatation and ileus, despite different treatment models and dosage reducing strategies. We report here a preterm patient who died because of severe diffuse necrotizing enterocolitis (NEC) after topical application of 0.5% cyclopentolate and 1.25% phenylephrine during ROP screening to emphasise the serious side effects of these agents.

  16. Retinal remodeling in the Tg P347L rabbit, a large-eye model of retinal degeneration.

    PubMed

    Jones, B W; Kondo, M; Terasaki, H; Watt, C B; Rapp, K; Anderson, J; Lin, Y; Shaw, M V; Yang, J-H; Marc, R E

    2011-10-01

    Retinitis pigmentosa (RP) is an inherited blinding disease characterized by progressive loss of retinal photoreceptors. There are numerous rodent models of retinal degeneration, but most are poor platforms for interventions that will translate into clinical practice. The rabbit possesses a number of desirable qualities for a model of retinal disease including a large eye and an existing and substantial knowledge base in retinal circuitry, anatomy, and ophthalmology. We have analyzed degeneration, remodeling, and reprogramming in a rabbit model of retinal degeneration, expressing a rhodopsin proline 347 to leucine transgene in a TgP347L rabbit as a powerful model to study the pathophysiology and treatment of retinal degeneration. We show that disease progression in the TgP347L rabbit closely tracks human cone-sparing RP, including the cone-associated preservation of bipolar cell signaling and triggering of reprogramming. The relatively fast disease progression makes the TgP347L rabbit an excellent model for gene therapy, cell biological intervention, progenitor cell transplantation, surgical interventions, and bionic prosthetic studies.

  17. Erbium:YAG laser photothermal retinal ablation in enucleated rabbit eyes.

    PubMed

    D'Amico, D J; Moulton, R S; Theodossiadis, P G; Yarborough, J M

    1994-06-15

    The erbium:YAG laser has been shown to produce precise tissue ablation because of the high water absorption of the 2.94-microns wave-length emitted by this laser. We used an experimental system to create lesions of various depths in the surface of the rabbit retina in enucleated eyes in vitro to examine the potential application to maneuvers such as retinotomy and the removal of epiretinal membranes in vitrectomy. With an air/retinal interface, single pulses produced discrete craters in the retinal surface with a depth proportional to fluence, ranging from 30 microns for a pulse of 1.3 J/cm2 to a full-thickness retinotomy at 3.9 J/cm2. An adjacent zone of coagulated tissue ranging in size from 15 to 40 microns was noted. Multiple pulses had an additive effect. With a fluid/retinal interface, 20 pulses of 3.6 J/cm2 produced a full-thickness retinotomy, with an adjacent zone of damaged tissue up to 1 mm, caused by effects of volatilization of intervening fluid. The erbium:YAG laser may have a role in vitreoretinal surgery.

  18. Simulating Dissolution of Intravitreal Triamcinolone Acetonide Suspensions in an Anatomically Accurate Rabbit Eye Model

    PubMed Central

    Horner, Marc; Muralikrishnan, R.

    2010-01-01

    ABSTRACT Purpose A computational fluid dynamics (CFD) study examined the impact of particle size on dissolution rate and residence of intravitreal suspension depots of Triamcinolone Acetonide (TAC). Methods A model for the rabbit eye was constructed using insights from high-resolution NMR imaging studies (Sawada 2002). The current model was compared to other published simulations in its ability to predict clearance of various intravitreally injected materials. Suspension depots were constructed explicitly rendering individual particles in various configurations: 4 or 16 mg drug confined to a 100 μL spherical depot, or 4 mg exploded to fill the entire vitreous. Particle size was reduced systematically in each configuration. The convective diffusion/dissolution process was simulated using a multiphase model. Results Release rate became independent of particle diameter below a certain value. The size-independent limits occurred for particle diameters ranging from 77 to 428 μM depending upon the depot configuration. Residence time predicted for the spherical depots in the size-independent limit was comparable to that observed in vivo. Conclusions Since the size-independent limit was several-fold greater than the particle size of commercially available pharmaceutical TAC suspensions, differences in particle size amongst such products are predicted to be immaterial to their duration or performance. PMID:20467888

  19. Posterior capsule opacification in rabbit eyes implanted with 1-piece and 3-piece hydrophobic acrylic intraocular lenses.

    PubMed

    Werner, Liliana; Mamalis, Nick; Izak, Andrea M; Pandey, Suresh K; Davis, Brandon L; Nilson, Chistian D; Weight, Christopher; Apple, David J

    2005-04-01

    To evaluate the outcome of posterior capsule opacification (PCO) after implantation in rabbit eyes of currently available 3-piece and 1-piece hydrophobic acrylic intraocular lenses (IOLs) with square optic edges. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. The 3-piece designs evaluated were the AR40e (Advanced Medical Optics Inc.) and the MA60AC (Alcon, Inc.); the 1-piece designs were the SA60AT and the SA30AT (Alcon, Inc.). Nine lenses of each type were implanted in a randomized manner by the same surgeon in 18 Dutch Belted pigmented rabbits. After a follow-up of 3 weeks, the rabbits were killed and analyses of the enucleated eyes were performed from the posterior or Miyake-Apple view. The intensity of central PCO, peripheral PCO, and Soemmering's ring formation was scored from 0 to 4. The area of Soemmering's ring formation was also scored from 0 to 4 based on the number of quadrants involved. Other parameters analyzed were capsulorhexis coverage of the IOL anterior surface, IOL centration, fixation, and presence of striae. Results from the posterior view were complemented by histopathologic evaluation of the eyes. No statistically significant difference was found between the 4 groups of IOLs in the parameters analyzed from the posterior view. When cell ingrowth occurred with the 1-piece designs, causing peripheral and central PCO formation, it was more likely to start at the optic-haptic junctions, as observed during the clinical follow-up with slitlamp examination and confirmed by gross and histopathologic analyses of the enucleated eyes. The square, truncated optic edge is the most important IOL design feature for PCO prevention. The optic-haptic junctions of the 1-piece designs appear to be sites where the barrier effect of the truncated optic edge is less effective.

  20. Pediatric eye injuries due to nonpowder guns in the United States, 2002-2012.

    PubMed

    Lee, Rachel; Fredrick, Douglas

    2015-04-01

    To identify epidemiologic trends in nonpowder gun-related pediatric eye injuries and to determine factors associated with severe injury requiring hospital admission. US emergency department data on pediatric eye injuries between 2002 and 2012 were reviewed using the National Electronic Injury Surveillance System. Literature review was conducted to determine trends in visual outcomes after treatment and use of eye protection. In 2012 roughly 3,161 children were treated in US emergency departments for nonpowder gun-related eye injuries. Since 2010 rates of severe nonpowder gun pediatric eye injury have increased by over 500% (P = 0.039). Specifically, while rates of hospital admission due to paintball gun eye injury have dropped precipitously (P = 0.0077), rates of admissions for air gun eye injuries have increased by over 600% since 2010 (P = 0.033). Children sustaining eye injury due to air guns are more likely to be diagnosed and admitted with foreign body or ocular puncture injury. Roughly 28% of documented cases of airsoft or BB gun-related injury had visual acuity worse than 20/50 after initial treatment. Over 98% of injuries occurred without eye protection. Air guns are rising in popularity and now account for the majority of pediatric eye injuries requiring hospital admissions. These eye injuries occur without ocular protection and may lead to permanent eye injury. Increasing regulations for eye protection, sales, and usage of air guns are needed to prevent serious pediatric eye injuries. Copyright © 2015 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

  1. Kinetics of (/sup 14/C-5) 8-methoxypsoralen uptake by UVA irradiated and non-irradiated rabbit eye tissues

    SciTech Connect

    Malinin, G.I.; Glew, W.B.; Roberts, W.P.; Nigra, T.P.

    1981-05-01

    Total 8-methoxypsoralen (8-MOP) in intact and UVA irradiated rabbit eye tissues and its unaltered fraction in aqueous and eye lenses were determined over the 24 hours after i.v. injection of (/sup 14/C-5) and carrier 8-MOP at the concentration of 50 microCi and 5 mg/kg. No 8-MOP was detected at the end of 24 hours in intact and irradiated aqueous, vitreous and retina in contrast to one hour when the respective levels were congruent to 220, greater than 0 and congruent to 160 ng/g. Eye-plasma drug concentration ratios were less than 0.5 initially, but increased thereafter. While the average lens 8-MOP levels of congruent to 140 ng/g remained unchanged for 24 hours, no unaltered drug was detected beyond eight hours. Measurable amounts of label at the end of 24 hours also persisted in the cornea, iris, sclera and conjunctiva.

  2. Assessment of the eye irritating properties of chemicals by applying alternatives to the Draize rabbit eye test: the use of QSARs and in vitro tests for the classification of eye irritation.

    PubMed

    Gerner, Ingrid; Liebsch, Manfred; Spielmann, Horst

    2005-06-01

    Huggins has reported on the current situation relating to the development of alternatives to the Draize eye irritation test with rabbits, and an ECVAM Working Group have reviewed the efforts needed in order to replace this animal test within the next 10 years by using the results of non-animal assessment methods. Our report reviews regulatory experience gained over the last 20 years with the EU chemicals notification procedure with respect to the assessment of eye lesions observed in Draize tests. The nature of eye lesions and their importance for classification and labelling of possible hazards to human eyes are evaluated and discussed, with a view to promoting the development of specific in vitro assays which are able to discriminate between eye damage, moderate eye irritation, and minor irritation effects which are completely reversible within a few days. Structural alerts for the prediction of eye irritation/corrosion hazards to be classified and labelled according to international classification criteria, are presented, which should be validated in accordance with internationally agreed (OECD) principles for (Q)SAR system validation. Physicochemical limit values for prediction of the absence of any eye irritation potential relevant for human health can make available a definition of the applicability domains of alternative methods developed for the replacement of the Draize eye irritation test.

  3. Proteoglycans in the microvasculature. I. Histochemical localization in microvessels of the rabbit eye.

    PubMed Central

    Ausprunk, D. H.; Boudreau, C. L.; Nelson, D. A.

    1981-01-01

    The ultrastructural organization of ruthenium red (RR) stainable material within small blood vessels located in the limbus of the rabbit eye was studied. Proteoglycans were identified in this material by digesting tissues with Streptomyces hyaluronidase, testicular hyaluronidase, chondroitinase ABC, or heparinase before ruthenium red staining. Neuraminidase digestion enabled separate identification of sialoglycoprotein. The luminal surface of endothelial cells demonstrates an RR-stained glycocalyx containing both sialoglycoprotein and proteoglycans, which are removed by testicular hyaluronidase and crude heparinase. The basal coat of endothelial cells and small granules (10-20 nm in diameter) located within the basal lamina stain with RR and are removed only by crude heparinase. The surface coat of smooth muscle cells and small granules (10-20 nm) within their basal laminas are also digested by crude heparinase. Large proteoglycan granules (20-50 nm), which are completely removed by testicular hyaluronidase and partially digested by Streptomyces hyaluronidase, are deposited between the connective tissue fibers of the media and adventitia. Other large granules that are attached to collagen fibers contain enzyme-resistant anionic materials. The surface coat of adventitial fibroblasts is removed only by crude heparinase. Thin filaments (3-5 nm in diameter) interconnect the cell coat material, basal lamina granules, and large connective tissue granules, to form a network of proteoglycans that traverses the intima, media, and adventitia. The highly ordered arrangement of proteoglycans in the microvascular wall suggests that these macromolecules play several roles in microvascular function. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 PMID:6165246

  4. Alternatives to In Vivo Draize Rabbit Eye and Skin Irritation Tests with a Focus on 3D Reconstructed Human Cornea-Like Epithelium and Epidermis Models.

    PubMed

    Lee, Miri; Hwang, Jee-Hyun; Lim, Kyung-Min

    2017-07-01

    Human eyes and skin are frequently exposed to chemicals accidentally or on purpose due to their external location. Therefore, chemicals are required to undergo the evaluation of the ocular and dermal irritancy for their safe handling and use before release into the market. Draize rabbit eye and skin irritation test developed in 1944, has been a gold standard test which was enlisted as OECD TG 404 and OECD TG 405 but it has been criticized with respect to animal welfare due to invasive and cruel procedure. To replace it, diverse alternatives have been developed: (i) For Draize eye irritation test, organotypic assay, in vitro cytotoxicity-based method, in chemico tests, in silico prediction model, and 3D reconstructed human cornea-like epithelium (RhCE); (ii) For Draize skin irritation test, in vitro cytotoxicity-based cell model, and 3D reconstructed human epidermis models (RhE). Of these, RhCE and RhE models are getting spotlight as a promising alternative with a wide applicability domain covering cosmetics and personal care products. In this review, we overviewed the current alternatives to Draize test with a focus on 3D human epithelium models to provide an insight into advancing and widening their utility.

  5. Alternatives to In Vivo Draize Rabbit Eye and Skin Irritation Tests with a Focus on 3D Reconstructed Human Cornea-Like Epithelium and Epidermis Models

    PubMed Central

    Lee, Miri; Hwang, Jee-Hyun; Lim, Kyung-Min

    2017-01-01

    Human eyes and skin are frequently exposed to chemicals accidentally or on purpose due to their external location. Therefore, chemicals are required to undergo the evaluation of the ocular and dermal irritancy for their safe handling and use before release into the market. Draize rabbit eye and skin irritation test developed in 1944, has been a gold standard test which was enlisted as OECD TG 404 and OECD TG 405 but it has been criticized with respect to animal welfare due to invasive and cruel procedure. To replace it, diverse alternatives have been developed: (i) For Draize eye irritation test, organotypic assay, in vitro cytotoxicity-based method, in chemico tests, in silico prediction model, and 3D reconstructed human cornea-like epithelium (RhCE); (ii) For Draize skin irritation test, in vitro cytotoxicity-based cell model, and 3D reconstructed human epidermis models (RhE). Of these, RhCE and RhE models are getting spotlight as a promising alternative with a wide applicability domain covering cosmetics and personal care products. In this review, we overviewed the current alternatives to Draize test with a focus on 3D human epithelium models to provide an insight into advancing and widening their utility. PMID:28744350

  6. Biochemical changes induced by intravitreally-injected doxorubicin in the iris-ciliary body and lens of the rabbit eye.

    PubMed

    Phylactos, A C; Unger, W G

    1998-01-01

    The aim of this study was to examine the chronic effects and mode of action of doxorubicin in ocular tissues. A dose of 10 microg (17.24 nanomoles) of doxorubicin hydrochloride in 20 microl sterile saline were intravitreally injected, under local anaesthesia, in one eye of 13 rabbits and 50 microg (86.20 nanomoles) were similarly injected in one eye of 3 rabbits. The contralateral eye received 20 microl of saline only. The dose of 50 microg induced initially mild uveal inflammation which became chronic and turned into circular iritis. Both doses of the drug induced cataract of the lens and clouding of the cornea within 2-3 months. The activity of superoxide dismutase, in iris-ciliary bodies and lenses treated with either 10 or 50 microg of the compound, was significantly lower relative to that in respective control tissues. In contrast to superoxide dismutase, catalase showed an increased activity in experimental tissues relative to control. The lysosomal hydrolases acid phosphatase, N-acetyl-B-D-glucosaminidase, aryl sulphatase and acid cathepsin, all showed significantly elevated activities in iris-ciliary body tissues one year after injection with the 50 microg doxorubicin. The reduction in superoxide dismutase activity may render ocular tissues susceptible to peroxidative attack and the increased activities of lysosomal hydrolases may contribute to chronic cell injury and inflammation.

  7. Prediction of ocular irritancy of 26 chemicals and 26 cosmetic products with isolated rabbit eye (IRE) test.

    PubMed

    Guo, Xiang; Yang, Xing Fen; Yang, Ying; Hans, Raabe; Cai, Jing Heng; Xue, Jin Yu; Tan, Xiao Hua; Xie, Xiao Ping; Xiong, Xi Kun; Huang, Jun Ming

    2012-06-01

    This study aims to establish and evaluate the methodology of isolated rabbit eye (IRE) test. IRE test was performed according to modifications of the in vitro toxicology (INVITTOX) Protocol No.85: Rabbit enucleated eye test by European Centre for the Validation of Alternative Methods (ECVAM), and then 26 chemicals and 26 cosmetic products were tested in both in vitro IRE and in vivo Draize tests. A statistical analysis was conducted to determine the relevance of the IRE test to the data generated in the Draize test. IRE test was established successfully in our laboratory. It was shown that ranking correlation and class concordance were fairly well between the IRE test and the Draize test for 26 reference chemicals (Fisher's Exact Test χ(2)=51.314, P<0.001; McNemar P=0.261; Gamma=0.960, P<0.001; Kappa=0.843, P<0.001) and 26 cosmetic products (Fisher's Exact Test χ(2)=15.522, P<0.001; McNemar P=0.311; Gamma=0.967, P<0.001; Kappa=0.611, P<0.001). IRE test was established successfully for in vitro testing of eye irritation as an alternative to Draize test. Copyright © 2012 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.

  8. Pharmacokinetics of topically applied recombinant human keratinocyte growth factor-2 in alkali-burned and intact rabbit eye.

    PubMed

    Cai, Jianqiu; Dou, Guifang; Zheng, Long; Yang, Ting; Jia, Xuechao; Tang, Lu; Huang, Yadong; Wu, Wencan; Li, Xiaokun; Wang, Xiaojie

    2015-07-01

    Keratinocyte growth factor-2 (KGF-2), an effective agent in the development of epithelial tissue and regeneration during corneal wound healing, is a potential therapeutic option to treat the corneal diseases with corneal epithelial defects. However the tissue distribution and pharmacokinetics of KGF-2 have not been explored yet in eye upon topical application. Using (125)I-labeled recombinant human KGF-2 ((125)I-rhKGF-2), tissue distribution of rhKGF-2 in alkali-burned and control rabbit eyes was studied. Our results revealed that (125)I-rhKGF-2 was distributed to all eye tissues examined. The highest radioactivity level was found in the cornea, followed by iris, sclera, ciliary body, lens, aqueous humor, vitreous body, and serum in a greatest to least order. The levels of (125)I-rhKGF-2 were higher in corneas of alkali-burned eyes than those in control eyes though without statistical significance. Calculated pharmacokinetic parameters of t1/2, Cmax, and Tmax of rhKGF-2 in the rabbit corneas were 3.4 h, 135.2 ng/ml, and 0.5 h, respectively. In iris, lens, aqueous humor, and tear, t1/2, Cmax, and Tmax values were 6.2, 6.5, 5.2, and 2.5 h; 23.2, 4.5, 24.1, and 29,498.9 ng/ml; and 1.0, 0.5, 0.5, and 1.0 h, respectively. Predominant and rapid accumulation of rhKGF-2 in corneas suggests that therapeutic doses of rhKGF-2 could be delivered by topical application for treatment of corneal diseases.

  9. Synergistic Effect of Artificial Tears Containing Epigallocatechin Gallate and Hyaluronic Acid for the Treatment of Rabbits with Dry Eye Syndrome

    PubMed Central

    Hung, Ya-Jung; Chen, Zhi-Yu; Fang, Hsu-Wei; Chen, Ko-Hua

    2016-01-01

    Dry eye syndrome (DES) is a common eye disease. Artificial tears (AT) are used to treat DES, but they are not effective. In this study, we assessed the anti-inflammatory effect of AT containing epigallocatechin gallate (EGCG) and hyaluronic acid (HA) on DES. Human corneal epithelial cells (HCECs) were used in the WST-8 assay to determine the safe dose of EGCG. Lipopolysaccharide-stimulated HCECs showing inflammation were treated with EGCG/HA. The expression of IL-1ß, IL-6, IL-8, and TNF-α was assessed by real-time PCR and AT physical properties such as the viscosity, osmolarity, and pH were examined. AT containing EGCG and HA were topically administered in a rabbit DES model established by treatment with 0.1% benzalkonium chloride (BAC). Tear secretion was assessed and fluorescein, H&E, and TUNEL staining were performed. Inflammatory cytokine levels in the corneas were also examined. The non-toxic optimal concentration of EGCG used for the treatment of HCECs in vitro was 10 μg/mL. The expression of several inflammatory genes, including IL-1ß, IL-6, IL-8, and TNF-α, was significantly inhibited in inflamed HCECs treated with 10 μg/mL EGCG and 0.1% (w/v) HA (E10/HA) compared to that in inflamed HCECs treated with either EGCG or HA alone. AT containing E10/HA mimic human tears, with similar osmolarity and viscosity and a neutral pH. Fluorescence examination of the ocular surface of mouse eyes showed that HA increased drug retention on the ocular surface. Topical treatment of DES rabbits with AT plus E10/HA increased tear secretion, reduced corneal epithelial damage, and maintained the epithelial layers and stromal structure. Moreover, the corneas of the E10/HA-treated rabbits showed fewer apoptotic cells, lower inflammation, and decreased IL-6, IL-8, and TNF-α levels. In conclusion, we showed that AT plus E10/HA had anti-inflammatory and mucoadhesive properties when used as topical eye drops and were effective for treating DES in rabbits. PMID:27336157

  10. Synergistic Effect of Artificial Tears Containing Epigallocatechin Gallate and Hyaluronic Acid for the Treatment of Rabbits with Dry Eye Syndrome.

    PubMed

    Tseng, Ching-Li; Hung, Ya-Jung; Chen, Zhi-Yu; Fang, Hsu-Wei; Chen, Ko-Hua

    2016-01-01

    Dry eye syndrome (DES) is a common eye disease. Artificial tears (AT) are used to treat DES, but they are not effective. In this study, we assessed the anti-inflammatory effect of AT containing epigallocatechin gallate (EGCG) and hyaluronic acid (HA) on DES. Human corneal epithelial cells (HCECs) were used in the WST-8 assay to determine the safe dose of EGCG. Lipopolysaccharide-stimulated HCECs showing inflammation were treated with EGCG/HA. The expression of IL-1ß, IL-6, IL-8, and TNF-α was assessed by real-time PCR and AT physical properties such as the viscosity, osmolarity, and pH were examined. AT containing EGCG and HA were topically administered in a rabbit DES model established by treatment with 0.1% benzalkonium chloride (BAC). Tear secretion was assessed and fluorescein, H&E, and TUNEL staining were performed. Inflammatory cytokine levels in the corneas were also examined. The non-toxic optimal concentration of EGCG used for the treatment of HCECs in vitro was 10 μg/mL. The expression of several inflammatory genes, including IL-1ß, IL-6, IL-8, and TNF-α, was significantly inhibited in inflamed HCECs treated with 10 μg/mL EGCG and 0.1% (w/v) HA (E10/HA) compared to that in inflamed HCECs treated with either EGCG or HA alone. AT containing E10/HA mimic human tears, with similar osmolarity and viscosity and a neutral pH. Fluorescence examination of the ocular surface of mouse eyes showed that HA increased drug retention on the ocular surface. Topical treatment of DES rabbits with AT plus E10/HA increased tear secretion, reduced corneal epithelial damage, and maintained the epithelial layers and stromal structure. Moreover, the corneas of the E10/HA-treated rabbits showed fewer apoptotic cells, lower inflammation, and decreased IL-6, IL-8, and TNF-α levels. In conclusion, we showed that AT plus E10/HA had anti-inflammatory and mucoadhesive properties when used as topical eye drops and were effective for treating DES in rabbits.

  11. Laser-induced hyperthemia in the treatment of ocular tumors: experimental evaluation of temperature rise in rabbits' eyes

    NASA Astrophysics Data System (ADS)

    Svaasand, Lars O.; Morinelli, Elisa; Gomer, Charles J.

    1990-08-01

    Experimental results for the optical properties of ocular tumors in the red to near infrared region from 600-900 nm and at the near infrared wavelength of 1064 nm are presented. The tumor models have been human retinoblastoma heterotransplanted in athyinic mice and B16 melanotic melanoma in athymic mice. The steady state retinal and tumor temperature rise during 1064 nm laser irradiation have been examined in vivo in normal albino and pigmented rabbits eye and in Greene''s melanoma inoculated in the retinachoroidal layers. 2.

  12. Three-dimensional reconstruction of blood vessels in the rabbit eye by X-ray phase contrast imaging

    PubMed Central

    2013-01-01

    Background A clear understanding of the blood vessels in the eye is helpful in the diagnosis and treatment of ophthalmic diseases, such as glaucoma. Conventional techniques such as micro-CT imaging and histology are not sufficiently accurate to identify the vessels in the eye, because their diameter is just a few microns. The newly developed medical imaging technology, X-ray phase-contrast imaging (XPCI), is able to distinguish the structure of the vessels in the eye. In this study, XPCI was used to identify the internal structure of the blood vessels in the eye. Methods After injection with barium sulfate via the ear border artery, an anesthetized rabbit was killed and its eye was fixed in vitro in 10% formalin solution. We acquired images using XPCI at the Shanghai Synchrotron Radiation Facility. The datasets were converted into slices by filtered back-projection (FBP). An angiographic score was obtained as a parameter to quantify the density of the blood vessels. A three-dimensional (3D) model of the blood vessels was then established using Amira 5.2 software. Results With XPCI, blood vessels in the rabbit eye as small as 18 μm in diameter and a sixth of the long posterior ciliary artery could be clearly distinguished. In the 3D model, we obtained the level 4 branch structure of vessels in the fundus. The diameters of the arteria centralis retinae and its branches are about 200 μm, 110 μm, 95 μm, 80 μm and 40 μm. The diameters of the circulus arteriosus iridis major and its branches are about 210 μm, 70 μm and 30 μm. Analysis of vessel density using the angiographic score showed that the blood vessels had maximum density in the fundus and minimum density in the area anterior to the equator (scores 0.27 ± 0.029 and 0.16 ± 0.032, respectively). We performed quantitative angiographic analysis of the blood vessels to further investigate the density of the vessels. Conclusions XPCI provided a feasible means to determine the structure of

  13. Supercritical fluid-mediated liposomes containing cyclosporin A for the treatment of dry eye syndrome in a rabbit model: comparative study with the conventional cyclosporin A emulsion.

    PubMed

    Karn, Pankaj Ranjan; Kim, Hyun Do; Kang, Han; Sun, Bo Kyung; Jin, Su-Eon; Hwang, Sung-Joo

    2014-01-01

    The objective of this study was to compare the efficacy of cyclosporin (CsA)-encapsulated liposomes with the commercially available CsA emulsion (Restasis) for the treatment of dry eye syndrome in rabbits. Liposomes containing CsA were prepared by the supercritical fluid (SCF) method consisted of phosphatidylcholine from soybean (SCF-S100) and egg lecithins (SCF-EPCS). An in vitro permeation study was carried out using artificial cellulose membrane in Franz diffusion cells. Dry eye syndrome was induced in male albino rabbits and further subdivided into untreated, Restasis-treated, EPCS, and S100-treated groups. Tear formation in the dry-eye-induced rabbits was evaluated using the Schirmer tear test. All formulations were also evaluated by ocular irritation tests using the Draize eye and winking methods with the determination of CsA concentration in rabbit tears. After the treatment, the Schirmer tear test value significantly improved in EPCS-treated (P=0.005) and S100-treated (P=0.018) groups compared to the Restasis-treated group. The AUC₀₋₂₄ h for rabbit's tear film after the administration of SCF-S100 was 32.75±9.21 μg·h/mg which was significantly higher than that of 24.59±8.69 μg·h/mg reported with Restasis. Liposomal CsA formulations used in this study showed lower irritation in rabbit eyes compared with Restasis. These results demonstrate that the novel SCF-mediated liposomal CsA promises a significant improvement in overcoming the challenges associated with the treatment of dry eyes.

  14. Axon reflex in ocular injury: sensory mediation of the response of the rabbit eye to laser irradiation of the iris.

    PubMed

    Butler, J M; Unger, W G; Cole, D F

    1980-10-01

    Laser irradiation of the rabbit iris produces an injury response consisting of prolonged miosis, uveal vasodilation and a transient rise of intraocular pressure (IOP) accompanied by a breakdown of the blood-aqueous barrier. This response has hitherto been attributed partly to prostaglandin (PG) mediation and partly to mediation by a non-cholinergic nervous pathway thought to be sensory in fuction. Responses of the rabbit eye to laser irritation were examined at specified intervals after diathermic coagulation of the epigasserian nerve tract. Both the intensity of the pupillary constriction and the increase in IOP were almost unaltered at 90 minutes but progressively decreased until at 4 days there was essentially no response to high energy laser irradiation in the denervated eye. It was evident that manifestation of the response is largely dependent upon the presence of intact and functional sensory nerves, and it is proposed that endogenous PGs exert some, if not all of their effects via sensory nerve endings. It is suggested that those terminals which are directly stimulated, whether by laser irradiation or by PGs formed during the injury, release some mediator to cause pupillary constriction. From thes terminals impulses pass orthodromically and antidromically by axon reflex to release further mediator from terminals in the region of the ciliary vessels or the major arterial circle. In this way the response is propagated and augmented.

  15. Study of wound-healing activity of bioregulators isolated from eye tissues and bovine serum in the model of experimental corneal injury in rabbits in vivo.

    PubMed

    Konstantinovsky, A A; Krasnov, M S; Yamskova, V P; Rybakova, E Yu; Yamskov, I A

    2012-06-01

    We compared wound-healing activity of bioregulators isolated from cattle cornea, serum, and retinal pigment epithelium on in vivo model of experimental corneal injury in rabbits. Bioregulators were instilled into the eye as solutions at a concentration corresponding to 10(-12) mg protein/ml. The animals were sacrificed on day 21 after injury and the corneas were examined histologically. The best wound-healing effect was produced by bioregulators isolated from the cornea and serum and instilled successively into rabbit eyes with an interval of 15-20 min twice a day: multicellular epithelium was observed in the wound, and slight inflammation, in the stroma.

  16. Determination of triamcinolone acetonide in silicone oil and aqueous humor of vitrectomized rabbits' eyes: Application for a pharmacokinetic study with intravitreal triamcinolone acetonide injections (Kenalog® 40).

    PubMed

    Fernandes-Cunha, Gabriella M; Saliba, Juliana B; Siqueira, Rubens C; Jorge, Rodrigo; Silva-Cunha, Armando

    2014-02-01

    A simple and accurate method including liquid-liquid extraction and protein precipitation procedures from silicone oil and aqueous humor samples followed by high-performance liquid chromatography (HPLC-UV) was developed and validated to determine the pharmacokinetic profile of triamcinolone acetonide in silicone oil and aqueous humor of rabbits' eyes submitted to the pars plana vitrectomy surgery. The method was successfully applied to quantify the drug remaining in silicone oil and aqueous humor (LOQ range of 1μg/mL). The triamcinolone acetonide remained in silicone oil and aqueous humor of vitrectomized rabbits' eyes for four weeks after the intravitreal injections.

  17. [Keratomycosis due to Fusarium oxysporum treated with the combination povidone iodine eye drops and oral fluconazole].

    PubMed

    Diongue, K; Sow, A S; Nguer, M; Seck, M C; Ndiaye, M; Badiane, A S; Ndiaye, J M; Ndoye, N W; Diallo, M A; Diop, A; Ndiaye, Y D; Dieye, B; Déme, A; Ndiaye, I M; Ndir, O; Ndiaye, D

    2015-12-01

    In developing countries where systemic antifungal are often unavailable, treatment of filamentous fungi infection as Fusarium is sometimes very difficult to treat. We report the case of a keratomycosis due to Fusarium oxysporum treated by povidone iodine eye drops and oral fluconazole. The diagnosis of abscess in the cornea was retained after ophthalmological examination for a 28-year-old man with no previous ophthalmological disease, addressed to the Ophthalmological clinic at the University Hospital Le Dantec in Dakar for a left painful red eye with decreased visual acuity lasting for 15 days. The patient did not receive any foreign body into the eye. Samples by corneal scraping were made for microbiological analysis and the patient was hospitalized and treated with a reinforced eye drops based treatment (ceftriaxone+gentamicin). The mycological diagnosis revealed the presence of a mold: F. oxysporum, which motivated the replacement of the initial treatment by eye drops containing iodized povidone solution at 1% because of the amphotericin B unavailability. Due to the threat of visual loss, oral fluconazole was added to the local treatment with eye drops povidone iodine. The outcome was favorable with a healing abscess and visual acuity amounted to 1/200th. Furthermore, we noted sequels such as pannus and pillowcase. The vulgarization of efficient topical antifungal in developing countries would be necessary to optimize fungal infection treatment. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  18. The Effect of Altitude on Intraocular Pressure in Vitrectomized Eyes with Sulfur Hexafluoride Tamponade by the Friedenwald Method: Rabbit Animal Model

    PubMed Central

    Fromow-Guerra, Jans; Solís-Vivanco, Adriana; Perez-Reguera, Adriana; Quiroz-Mercado, Hugo; Meza-de Regil, Armando; Papa-Oliva, Gabriela; Morales-Cantón, Virgilio

    2016-01-01

    The aim of this study is to assess the change in intraocular pressure after a road trip, in eyes with different levels of filling with gas tamponade. Five rabbit eyes were subject to pars plana vitrectomy and gas tamponade (filling percentage: 25%, 50%, and 100% of nonexpansile SF6, 100% saline solution, and 100% room air). A sixth eye was injected with 0.35 cc of undiluted SF6 without vitrectomy. Guided by global positioning system, they were driven to the highest point of the highway connecting Mexico City with Puebla city and back, stopping every 300 m to assess intraocular pressure. The rabbit's scleral rigidity and estimation for human eyes were done by using the Friedenwald nomogram. Maximum altitude was 3209 m (Δ949 m). There were significant differences in intraocular pressure on the rabbit eyes filled with SF6 at 100%, 50%, 25%, and 100% room air. Per every 100 m of altitude rise, the intraocular pressure increased by 1.53, 1.0046, 0.971, and 0.97 mmHg, respectively. Using the human Friedenwald rigidity coefficient, the human eye estimate for intraocular pressure change was 2.1, 1.8, 1.4, and 1.1 mmHg per every 100 m of attitude rise. Altitude changes have a significant impact on intraocular pressure. The final effect depends on the percentage of vitreous cavity fill and scleral rigidity. PMID:27957500

  19. The Effect of Altitude on Intraocular Pressure in Vitrectomized Eyes with Sulfur Hexafluoride Tamponade by the Friedenwald Method: Rabbit Animal Model.

    PubMed

    Fromow-Guerra, Jans; Solís-Vivanco, Adriana; Velez-Montoya, Raul; Perez-Reguera, Adriana; Quiroz-Mercado, Hugo; Meza-de Regil, Armando; Papa-Oliva, Gabriela; Morales-Cantón, Virgilio

    2016-01-01

    The aim of this study is to assess the change in intraocular pressure after a road trip, in eyes with different levels of filling with gas tamponade. Five rabbit eyes were subject to pars plana vitrectomy and gas tamponade (filling percentage: 25%, 50%, and 100% of nonexpansile SF6, 100% saline solution, and 100% room air). A sixth eye was injected with 0.35 cc of undiluted SF6 without vitrectomy. Guided by global positioning system, they were driven to the highest point of the highway connecting Mexico City with Puebla city and back, stopping every 300 m to assess intraocular pressure. The rabbit's scleral rigidity and estimation for human eyes were done by using the Friedenwald nomogram. Maximum altitude was 3209 m (Δ949 m). There were significant differences in intraocular pressure on the rabbit eyes filled with SF6 at 100%, 50%, 25%, and 100% room air. Per every 100 m of altitude rise, the intraocular pressure increased by 1.53, 1.0046, 0.971, and 0.97 mmHg, respectively. Using the human Friedenwald rigidity coefficient, the human eye estimate for intraocular pressure change was 2.1, 1.8, 1.4, and 1.1 mmHg per every 100 m of attitude rise. Altitude changes have a significant impact on intraocular pressure. The final effect depends on the percentage of vitreous cavity fill and scleral rigidity.

  20. Hyperpolarization of rabbit superior cervical ganglion cells due to activity of an electrogenic sodium pump

    PubMed Central

    Lees, G.M.; Wallis, D.I.

    1974-01-01

    1 The mechanisms underlying the hyperpolarization which follows depolarization of rabbit superior cervical ganglion cells by acetylcholine, have been investigated and compared with the mechanisms responsible for the hyperpolarizations induced by orthodromic stimulation of the ganglion. 2 The amplitude of the drug-induced hyperpolarization (after-hyperpolarization) was diminished when [Na+]0 and the duration of the preceding depolarization were reduced. 3 In K+-free solutions, the amplitude of the after-hyperpolarization was often diminished and its rate of development was reduced. In 12.5 mM K+-Krebs solutions, the amplitude and rate of development of the after-hyperpolarization were increased; the potential was still present when the resting potential was at or close to EK. 4 Ouabain (10 μM) prevented or greatly diminished the after-hyperpolarization. The rates of onset and decay of the after-hyperpolarization were reduced in glucose-free solutions. 5 It is, therefore, concluded that the after-hypolarization is due to the activity of an electrogenic sodium pump. 6 The positive after-potential associated with the ganglionic action potential was increased in K+-free solutions and diminished when the resting potential approached EK, indicating that it is due to a period of increased K+ conductance. In the presence of high concentrations of hexamethonium (276 μM), the P wave was not selectively depressed by ouabain and has been shown by other workers to be due to a mechanism not involving an increased potassium conductance. It is concluded, therefore, that the positive after-potential, the P wave and the after-hyperpolarization are due to different mechanisms. PMID:4823465

  1. Decrease in Corneal Damage due to Benzalkonium Chloride by the Addition of Mannitol into Timolol Maleate Eye Drops.

    PubMed

    Nagai, Noriaki; Yoshioka, Chiaki; Tanino, Tadatoshi; Ito, Yoshimasa; Okamoto, Norio; Shimomura, Yoshikazu

    2015-01-01

    We investigated the protective effects of mannitol on corneal damage caused by benzalkonium chloride (BAC), which is used as a preservative in commercially available timolol maleate eye drops, using rat debrided corneal epithelium and a human cornea epithelial cell line (HCE-T). Corneal wounds were monitored using a fundus camera TRC-50X equipped with a digital camera; eye drops were instilled into rat eyes five times a day after corneal epithelial abrasion. The viability of HCE-T cells was calculated by TetraColor One; and Escherichia coli (ATCC 8739) were used to measure antimicrobial activity. The reducing effects on transcorneal penetration and intraocular pressure (IOP) of the eye drops were determined using rabbits. The corneal wound healing rate and rate constant (kH), as well as cell viability, were higher following treatment with 0.005% BAC solution containing 0.5% mannitol than in the case BAC solution alone; the antimicrobial activity was approximately the same for BAC solutions with and without mannitol. In addition, the kH for rat eyes instilled with commercially available timolol maleate eye drops containing 0.5% mannitol was significantly higher than that for eyes instilled with timolol maleate eye drops without mannitol, and the addition of mannitol did not affect the corneal penetration or IOP reducing effect of the timolol maleate eye drops. A preservative system comprising BAC and mannitol may provide effective therapy for glaucoma patients requiring long-term treatment with anti-glaucoma agents.

  2. Damage threshold in adult rabbit eyes after scleral cross-linking by riboflavin/blue light application.

    PubMed

    Iseli, Hans Peter; Körber, Nicole; Karl, Anett; Koch, Christian; Schuldt, Carsten; Penk, Anja; Liu, Qing; Huster, Daniel; Käs, Josef; Reichenbach, Andreas; Wiedemann, Peter; Francke, Mike

    2015-10-01

    Several scleral cross-linking (SXL) methods were suggested to increase the biomechanical stiffness of scleral tissue and therefore, to inhibit axial eye elongation in progressive myopia. In addition to scleral cross-linking and biomechanical effects caused by riboflavin and light irradiation such a treatment might induce tissue damage, dependent on the light intensity used. Therefore, we characterized the damage threshold and mechanical stiffening effect in rabbit eyes after application of riboflavin combined with various blue light intensities. Adult pigmented and albino rabbits were treated with riboflavin (0.5 %) and varying blue light (450 ± 50 nm) dosages from 18 to 780 J/cm(2) (15 to 650 mW/cm(2) for 20 min). Scleral, choroidal and retinal tissue alterations were detected by means of light microscopy, electron microscopy and immunohistochemistry. Biomechanical changes were measured by shear rheology. Blue light dosages of 480 J/cm(2) (400 mW/cm(2)) and beyond induced pathological changes in ocular tissues; the damage threshold was defined by the light intensities which induced cellular degeneration and/or massive collagen structure changes. At such high dosages, we observed alterations of the collagen structure in scleral tissue, as well as pigment aggregation, internal hemorrhages, and collapsed blood vessels. Additionally, photoreceptor degenerations associated with microglia activation and macroglia cell reactivity in the retina were detected. These pathological alterations were locally restricted to the treated areas. Pigmentation of rabbit eyes did not change the damage threshold after a treatment with riboflavin and blue light but seems to influence the vulnerability for blue light irradiations. Increased biomechanical stiffness of scleral tissue could be achieved with blue light intensities below the characterized damage threshold. We conclude that riboflavin and blue light application increased the biomechanical stiffness of scleral tissue at

  3. Diminution and reversal of eye movements induced by local stimulation of rabbit cerebellar flocculus after partial destruction of the inferior olive.

    PubMed

    Dufossé, M; Ito, M; Miyashita, Y

    1978-09-15

    After the dorsal cap and adjacent ventrolateral outgrowth regions of the inferior olive had been chronically destroyed in the rabbits, the eye movements evoked by local stimulation of the flocculus were reduced in amplitude and reversed in direction, indicating that the inhibition by flocculus Purkinje cells of vestibulo-ocular relay neurons could no longer be actuated by the stimulation.

  4. [A comparative evaluation of the oxidant and antioxidant blood systems in rabbits with caustic burns of the eyes in their treatment by synthetic and natural antioxidants].

    PubMed

    Travkin, A G; Shul'gina, N A

    2004-01-01

    A method of provoking a caustic burn was described on the basis of experiments made in 36 rabbits (72 eyes) who were shared between 2 groups. Effects from histochrom, a natural antioxidant, and from emoxipin, a synthetic antioxidant, produced on the lipid-peroxidation parameters at early stages of ocular burn disease were studied. A higher clinical efficiency of histochrom versus emoxipin was demonstrated.

  5. In vivo evaluation of a biodegradable donut-shaped minitablet for prolonged posterior segment drug delivery in the rabbit eye model.

    PubMed

    Choonara, Yahya E; Pillay, Viness; Danckwerts, Michael Paul; Carmichael, Trevor R; Meyer, Leith C R; Du Toit, Lisa C; Naylor, Simon; Wanblad, Carla

    2011-05-01

    This study focused on the in vivo evaluation of a biodegradable ganciclovir-loaded donut-shaped minitablet (DSMT) for controlled drug delivery in the New Zealand white albino rabbit eye model. Specialized tablet tooling was used to manufacture a poly(lactic-co-glycolic acid) DSMT device that was implanted into 18 rabbits through the pars plana/peripheral retina of the right eyes of each rabbit. The left eyes were used as controls. Possible adverse effects on ocular tissues were assessed by histomorphology, slit-lamp biomicroscopy, intraocular pressure (IOP) measurements, and indirect ophthalmoscopy. The ex vivo microenvironmental vitreous pH was also monitored. Rabbits were euthanized at predetermined intervals and the residual devices, vitreous humor, and ocular tissue were retrieved and stored appropriately until further analysis. The DSMT was well tolerated up to 72 days and was still visible in the superotemporal quadrant of the eye. The mean IOP range (6-8 mmHg; N = 18) and changes in vitreous pH (7.25 ± 0.01; N = 3) correlated with baseline measurements. The DSMT displayed constant ganciclovir release at a rate of 2.02 μ g/h maintained within the 50% effective dose for human cytomegalovirus retinitis (N = 3). The design simplicity and application of the biodegradable DSMT device may provide a superior alternative for prolonged rate-controlled intraocular drug delivery.

  6. The vitreous after C3F8 gas instillation: long-term histologic findings after spontaneous reabsorption of the gas in rabbit eyes.

    PubMed

    Faulborn, J; Bowald, S

    1987-01-01

    Perfluoropropane gas (C3F8) was injected intravitreally into rabbit eyes to displace the vitreous. Histologic examination by light and scanning electron microscopy revealed the vitreous material slowly expanded up to a nearly normal configuration during a follow-up of 6 months. Neither posterior vitreous detachment nor liquefaction of the vitreous could be observed.

  7. Hybrid Formulations of Liposomes and Bioadhesive Polymers Improve the Hypotensive Effect of the Melatonin Analogue 5-MCA-NAT in Rabbit Eyes

    PubMed Central

    Palma, Santiago; Allemandi, Daniel; Herrero-Vanrell, Rocío; Molina-Martínez, Irene T.

    2014-01-01

    For the treatment of chronic ocular diseases such as glaucoma, continuous instillations of eye drops are needed. However, frequent administrations of hypotensive topical formulations can produce adverse ocular surface effects due to the active substance or other components of the formulation, such as preservatives or other excipients. Thus the development of unpreserved formulations that are well tolerated after frequent instillations is an important challenge to improve ophthalmic chronic topical therapies. Furthermore, several components can improve the properties of the formulation in terms of efficacy. In order to achieve the mentioned objectives, we have developed formulations of liposomes (150–200 nm) containing components similar to those in the tear film and loaded with the hypotensive melatonin analog 5-methoxycarbonylamino-N-acetyltryptamine (5-MCA-NAT, 100 µM). These formulations were combined with mucoadhesive (sodium hyaluronate or carboxymethylcellulose) or amphiphilic block thermosensitive (poloxamer) polymers to prolong the hypotensive efficacy of the drug. In rabbit eyes, the decrease of intraocular pressure with 5-MCA-NAT-loaded liposomes that were dispersed with 0.2% sodium hyaluronate, 39.1±2.2%, was remarkably higher compared to other liposomes formulated without or with other bioadhesive polymers, and the effect lasted more than 8 hours. According to the results obtained in the present work, these technological strategies could provide an improved modality for delivering therapeutic agents in patients with glaucoma. PMID:25329636

  8. Ocular pharmacokinetics of bimatoprost formulated in DuraSite compared to bimatoprost 0.03% ophthalmic solution in pigmented rabbit eyes

    PubMed Central

    Shafiee, Afshin; Bowman, Lyle M; Hou, Eddie; Hosseini, Kamran

    2013-01-01

    Purpose To compare the aqueous humor (AH) and iris-ciliary body (ICB) concentration of bimatoprost in rabbit eyes treated with ISV-215 (0.03% bimatoprost formulated in DuraSite) with the marketed product bimatoprost 0.03% ophthalmic solution. Methods The left eye of rabbits received a single topical instillation of either ISV-215 (n = 32 eyes) or bimatoprost 0.03% (n = 32 eyes). At predetermined time points, levels of bimatoprost and bimatoprost acid in the AH and the ICB were quantified by HPLC-MS/MS. Results Both bimatoprost and bimatoprost acid were detected in the AH and the ICB within 15 minutes of dosing. Bimatoprost acid concentrations in both compartments were markedly higher than bimatoprost. There was a statistically significant (P < 0.01) increase in the concentration of the prodrug in the AH and its acid form in the ICB in animals treated with ISV-215 compared to bimatoprost 0.03%. In the ISV-215-treated rabbit eyes, the highest concentrations of bimatoprost and bimatoprost acid were in the ICB and AH, respectively, while in the bimatoprost 0.03%-treated eyes, no differences in the drug content of the selected ocular tissues were observed. Conclusions Bimatoprost 0.03% formulated in DuraSite has superior ocular distribution and area under the curve compared to bimatoprost 0.03% in rabbit eyes. This improvement in the pharmacokinetic parameters of ISV-215 may provide us with a better platform to optimize a bimatoprost formulation that offers the same degree of efficacy in lowering intraocular pressure and improved therapeutic index in glaucomatous patients by lessening the ocular side effects associated with long-term use of topical prostaglandin F2α analogs. PMID:23940414

  9. Ocular Penetration and Efficacy of Levofloxacin Using Different Drug-Delivery Techniques for the Prevention of Endophthalmitis in Rabbit Eyes with Posterior Capsule Rupture

    PubMed Central

    Uda, Takahiro; Mitani, Arisa; Tasaka, Yoshitaka; Kawasaki, Shiro; Mito, Tsuyoshi; Ohashi, Yuichi

    2014-01-01

    Abstract Purpose: To evaluate the effects of different drug-delivery techniques for levofloxacin (LVFX) in ocular penetration and the prevention of endophthalmitis using an aphakic rabbit model with posterior capsule rupture (PCR). Methods: LVFX was administered to aphakic rabbit eyes with or without PCR using eye drops (EDs), subconjunctival injection (SCI), or intracameral (IC) injection. The concentration of the drug in the vitreous and aqueous humors was estimated at 2 h after injection. In another study, aphakic rabbit eyes with PCR were inoculated with Enterococcus faecalis, immediately followed by 0.5% LVFX ED, 0.5% moxifloxacin (MFLX) ED, LVFX IC (500 μg/0.1 mL), or IC saline. EDs were administered 0, 3, and 6 h after surgery. Changes on electroretinography (ERG) and intraocular bacterial growth were determined sequentially until 48 h after inoculation. Results: The concentrations of LVFX at 2 h after IC were higher in the aqueous humor and the vitreous cavity of eyes with or without PCR, compared with EDs or SCI. Eyes treated with LVFX ED, MFLX ED, or IC saline showed a significantly greater reduction in b-wave amplitude on ERG at 48 h compared with eyes treated with LVFX IC. The number of bacteria recovered from the vitreous humor in eyes treated with IC LVFX at 48 h was significantly less than from eyes that received other treatments. Conclusion: The LVFX IC was effective at suppressing endophthalmitis caused by E. faecalis in eyes with a PCR. PMID:24410272

  10. Computational model for calculating body-core temperature elevation in rabbits due to whole-body exposure at 2.45 GHz.

    PubMed

    Hirata, Akimasa; Sugiyama, Hironori; Kojima, Masami; Kawai, Hiroki; Yamashiro, Yoko; Fujiwara, Osamu; Watanabe, Soichi; Sasaki, Kazuyuki

    2008-06-21

    In the current international guidelines and standards with regard to human exposure to electromagnetic waves, the basic restriction is defined in terms of the whole-body average-specific absorption rate. The rationale for the guidelines is that the characteristic pattern of thermoregulatory response is observed for the whole-body average SAR above a certain level. However, the relationship between energy absorption and temperature elevation was not well quantified. In this study, we improved our thermal computation model for rabbits, which was developed for localized exposure on eye, in order to investigate the body-core temperature elevation due to whole-body exposure at 2.45 GHz. The effect of anesthesia on the body-core temperature elevation was also discussed in comparison with measured results. For the whole-body average SAR of 3.0 W kg(-1), the body-core temperature in rabbits elevates with time, without becoming saturated. The administration of anesthesia suppressed body-core temperature elevation, which is attributed to the reduced basal metabolic rate.

  11. Computational model for calculating body-core temperature elevation in rabbits due to whole-body exposure at 2.45 GHz

    NASA Astrophysics Data System (ADS)

    Hirata, Akimasa; Sugiyama, Hironori; Kojima, Masami; Kawai, Hiroki; Yamashiro, Yoko; Fujiwara, Osamu; Watanabe, Soichi; Sasaki, Kazuyuki

    2008-06-01

    In the current international guidelines and standards with regard to human exposure to electromagnetic waves, the basic restriction is defined in terms of the whole-body average-specific absorption rate. The rationale for the guidelines is that the characteristic pattern of thermoregulatory response is observed for the whole-body average SAR above a certain level. However, the relationship between energy absorption and temperature elevation was not well quantified. In this study, we improved our thermal computation model for rabbits, which was developed for localized exposure on eye, in order to investigate the body-core temperature elevation due to whole-body exposure at 2.45 GHz. The effect of anesthesia on the body-core temperature elevation was also discussed in comparison with measured results. For the whole-body average SAR of 3.0 W kg-1, the body-core temperature in rabbits elevates with time, without becoming saturated. The administration of anesthesia suppressed body-core temperature elevation, which is attributed to the reduced basal metabolic rate.

  12. The effect of timolol maleate on the disruption of the blood-aqueous barrier in the rabbit eye

    SciTech Connect

    Holmdahl, G.; Bengtsson, E.

    1981-06-01

    A disruption of the blood-aqueous barrier in rabbit eyes was elicited by use of topical prostaglandin E2(PGE2), infrared irradiation of the iris, or by subcutaneous alpha-melanocyte-stimulating hormone (alpha-MSH). The aqueous flare provoked was measured quantitatively with a photoelectric instrument. The effect of the (topical) beta-adrenergic antagonist timolol maleate on the breakdown of the blood-aqueous barrier was tested. Timolol applied topically in very large doses had no effect on exogenously administered PGE2. However, even in a very small concentration applied topically, timolol reduced the flare response to both infrared irradiation and alpha-MSH. These results support the theory that the effect of alpha-MSH and infrared irradiation on the blood-aqueous barrier is dependent on intact beta-adrenergic receptor sites.

  13. In Vivo Non Linear Optical (NLO) Imaging in Live Rabbit Eyes Using the Heidelberg Two-Photon Laser Ophthalmoscope

    PubMed Central

    Hao, Ming; Flynn, Kevin; Nien-Shy, Chyong; Jester, Bryan E.; Winkler, Moritz; Brown, Donald J.; La Schiazza, Olivier; Bille, Josef; Jester, James V.

    2010-01-01

    Imaging of non-linear optical (NLO) signals generated from the eye using ultrafast pulsed lasers has been limited to the study of ex vivo tissues because of the use of conventional microscopes with slow scan speeds. The purpose of this study was to evaluate the ability of a novel, high scan rate ophthalmoscope to generate NLO signals using an attached femtosecond laser. NLO signals were generated and imaged in live, anesthetized albino rabbits using a newly designed Heidelberg Two-Photon Laser Ophthalmoscope with attached 25 mW femtosecond laser having a central wavelength of 780 nm, pulsewidth of 75 fs, and a repetition rate of 50 MHz. To assess two-photon excited fluorescent (TPEF) signal generation, cultured rabbit corneal fibroblasts (RCF) were first labeled by Blue-green fluorescent FluoSpheres (1 μm diameter) and then cells were micro-injected into the central cornea. Clumps of RCF cells could be detected by both reflectance and TPEF imaging at 6 hours after injection. By 6 days, RCF containing fluorescent microspheres confirmed by TPEF showed a more spread morphology and had migrated from the original injection site. Overall, this study demonstrates the potential of using NLO microscopy to sequentially detect TPEF signals from live, intact corneas. We conclude that further refinement of the Two-photon laser Ophthalmoscope should lead to the development of an important, new clinical instrument capable of detecting NLO signals from patient corneas. PMID:20558159

  14. In vivo non-linear optical (NLO) imaging in live rabbit eyes using the Heidelberg Two-Photon Laser Ophthalmoscope.

    PubMed

    Hao, Ming; Flynn, Kevin; Nien-Shy, Chyong; Jester, Bryan E; Winkler, Moritz; Brown, Donald J; La Schiazza, Olivier; Bille, Josef; Jester, James V

    2010-08-01

    Imaging of non-linear optical (NLO) signals generated from the eye using ultrafast pulsed lasers has been limited to the study of ex vivo tissues because of the use of conventional microscopes with slow scan speeds. The purpose of this study was to evaluate the ability of a novel, high scan rate ophthalmoscope to generate NLO signals using an attached femtosecond laser. NLO signals were generated and imaged in live, anesthetized albino rabbits using a newly designed Heidelberg Two-Photon Laser Ophthalmoscope with attached 25 mW fs laser having a central wavelength of 780 nm, pulsewidth of 75 fs, and a repetition rate of 50 MHz. To assess two-photon excited fluorescent (TPEF) signal generation, cultured rabbit corneal fibroblasts (RCF) were first labeled by Blue-green fluorescent FluoSpheres (1 mum diameter) and then cells were micro-injected into the central cornea. Clumps of RCF cells could be detected by both reflectance and TPEF imaging at 6 h after injection. By 6 days, RCF containing fluorescent microspheres confirmed by TPEF showed a more spread morphology and had migrated from the original injection site. Overall, this study demonstrates the potential of using NLO microscopy to sequentially detect TPEF signals from live, intact corneas. We conclude that further refinement of the Two-photon laser Ophthalmoscope should lead to the development of an important, new clinical instrument capable of detecting NLO signals from patient corneas. Copyright 2010 Elsevier Ltd. All rights reserved.

  15. Pathologic fracture of the femur due to endometrial adenocarcinoma metastasis in a female pet rabbit (Oryctolagus cuniculi).

    PubMed

    Haist, Verena; Hirschfeld, Simon Gonzales; Mallig, Carolin; Fehr, Michael; Baumgärtner, Wolfgang

    2010-01-01

    This case report describes the clinical, pathomorphological and histopathological findings in a 12-year-old female pet rabbit with a pathologic fracture of the femur due to a metastasising endometrial adenocarcinoma. The animal was presented due to a history of right hindlimb lameness and inappetence. A fracture of the right femur with adjacent lyric bone lesions was detected by clinical and X-ray examination. Necropsy and histopathology revealed an endometrial adenocarcinoma with metastasis to the right femoral bone, resulting in the pathologic fracture. In both locations, tumour cells were immunohistochemically positive for pan-cytokeratin. Additionally, the animal suffered from an Encephalitozoon cuniculi infection which manifested itself in a multifocal granulomatous encephalitis and bilateral chronic inflammatory lesions in the kidneys.The report shows that in case of bone fractures in female pet rabbits the possibility of a pathologic fracture due to metastasising endometrial adenocarcinoma has to be considered.

  16. Thermal elevation in the human eye and head due to the operation of a retinal prosthesis.

    PubMed

    Gosalia, Keyoor; Weiland, James; Humayun, Mark; Lazzi, Gianluca

    2004-08-01

    An explicit finite-difference time-domain formulation of the bio-heat equation is employed with a three-dimensional head eye model to evaluate the temperature increase in the eye and surrounding head tissues due to the operation of the implanted stimulator IC chip of a retinal prosthesis designed to restore partial vision to the blind. As a first step, a validation of the thermal model and method used is carried out by comparison with in vivo measurements of intraocular heating performed in the eyes of dogs. Induced temperature increase in the eye and surrounding tissues is then estimated for several different operational conditions of the implanted chip. In the vitreous cavity, temperature elevation of 0.26 degrees C is observed after 26 min for a chip dissipating 12.4 mW when positioned in the mid-vitreous cavity while it is 0.16 degrees C when the chip is positioned in the anterior portion between the eye's ciliary muscles. Corresponding temperature rises observed on chip are 0.82 degrees C for both the positions of the chip. A comprehensive account of temperature elevations in different tissues under different operational conditions is presented.

  17. Ocular pharmacokinetics of carnosine 5% eye drops following topical application in rabbit.

    PubMed

    Tianyang, Zhou; Ling, Zhu; Liya, Wang; Junjie, Zhang

    2011-02-01

    To evaluated the ocular pharmacokinetics of carnosine (CAR, a biologically active dipeptide which occurs naturally throughout the human body) 5% eye drops following topical application. CAR 5% eye drops were topically applied repeatedly (50 μL × 4) at an interval of 5 min. Aqueous humor and lens were collected after 5, 15, 30, 45, 60, 90, 120, 150, and 180 min. CAR concentration was determined by high performance liquid chromatography-tandem quadrupole mass spectrometer (HPLC-MS/MS). CAR concentration in treated eyes was significantly higher than control eyes. Peak concentration (C(max)) of carnosine in treated aqueous humor occurred 60 min following topical administration, with the administrated concentration (total-endogenous concentration) of 40.9 ± 18.9 μg/mL. The area under the concentration-time curve between 0 and 180 min (AUC(0-180)) was 3,276.8 (μg/mL) × min. CAR concentration in treated lens rises to effective level rapidly and changes slightly with time after topical administration. The administrated concentration of car in lens at the last time point (180 min, 1.92 ± 1.65 μg/mL) was not significantly different with the highest value (15 min, 2.11 ± 1.83 μg/mL). CAR 5% eye drops were likely to be absorbed into aqueous humor efficiently and accumulated in lens. More attention should be put onto enhancing the penetration of CAR into lens capsule.

  18. Potentiation of collagen synthesis in explants of the rabbit eye by 5 beta-dihydrocortisol

    SciTech Connect

    Southren, A.L.; Hernandez, M.R.; l'Hommedieu, D.; Gordon, G.G.; Weinstein, B.I.

    1986-12-01

    The biologic effect of 5 beta-dihydrocortisol on collagen synthesis was evaluated. The metabolite was found to potentiate subthreshold levels of dexamethasone in increasing /sup 3/H-proline incorporation in cells of the outflow region of the rabbit. Digestion of the tissue with highly purified collagenase indicated that the /sup 3/H-proline was incorporated into collagen type protein. This study demonstrates another biologic activity of 5 beta-dihydrocortisol, a metabolite found to accumulate in cells cultured from trabeculectomy specimens from patients with primary open angle glaucoma.

  19. Measuring depth of injury (DOI) in an isolated rabbit eye irritation test (IRE) using biomarkers of cell death and viability.

    PubMed

    Jester, James V; Ling, Joseph; Harbell, John

    2010-03-01

    While DOI is a mechanistic correlate to the ocular irritation response, attempts to measure DOI in alternative tests have been limited to qualitative histopathologic assessment by veterinarian pathologists. The purpose of this study was to determine whether DOI could be measured objectively by fluorescent staining for biomarkers of cell death and viability using an ex vivo isolated rabbit eye (IRE) test. A panel of nine materials characterized by in vivo DOI were selected that caused slight (3% acetic acid and 5% SDS), mild (acetone, sodium hypochlorite and 10% acetic acid), moderate (cyclohexanol and parafluoroanaline) and severe (8% sodium hydroxide and 10% benzalkonium chloride) irritation. Materials were then tested using a modified IRE test with 3h recovery and then processed for cyrosectioning and staining using a TUNEL assay to detect cell death, phalloidin to detect intracellular f-actin and DAPI staining to detect nuclei. Control eyes treated with water showed intense phalloidin staining of the corneal epithelium and stromal keratocytes but no TUNEL labeling. In general, eyes treated with mild, moderate and severe irritants showed regions of TUNEL labeled epithelial and keratocyte nuclei with no phalloidin stain overlying phalloidin stained, undamaged cells. DOI measurements showed that slight irritants damaged<40% of the epithelium, mild and moderate irritants damaged>50% of the epithelium, extending at times into the anterior stroma (<20%), and the severe irritant damaged>50% of the stroma. Regression analysis between ex vivo and in vivo DOI showed a significant (p<0.007) correlation (r=0.785). These data suggest that fluorescent staining of fixed and sectioned tissue using biomarkers can be used to objectively identify the depth of injury caused by ocular irritants. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  20. Proteomic analysis revealed the altered tear protein profile in a rabbit model of Sjögren's syndrome-associated dry eye.

    PubMed

    Zhou, Lei; Wei, Ruihua; Zhao, Ping; Koh, Siew Kwan; Beuerman, Roger W; Ding, Chuanqing

    2013-08-01

    Sjögren's syndrome (SS) is an autoimmune disease that results in pathological dryness of mouth and eye. The diagnosis of SS depends on both clinical evaluation and specific antibodies. The goal of this study was to use quantitative proteomics to investigate changes in tear proteins in a rabbit model of SS-associated dry eye, induced autoimmune dacryoadenitis (IAD). Proteomic analysis was performed by iTRAQ and nano LC-MS/MS on tears collected from the ocular surface, and specific proteins were verified by high resolution MRM. It was found that in the tears of IAD rabbits at 2 and 4 weeks after induction, S100 A6, S100 A9, and serum albumin were upregulated, whereas serotransferrin (TF), prolactin-inducible protein (PIP), polymeric immunoglobulin receptor (pIgR), and Ig gamma chain C region were downregulated. High resolution MRM with mTRAQ labeling verified the changes in S100 A6, TF, PIP, and pIgR. Our results indicated significant changes of tear proteins in IAD rabbits, suggesting these proteins could potentially be used as biomarkers for the diagnosis and prognosis of dry eye. Several of these proteins were also found in the tears of non-SS dry eye patients indicating a common basis of ocular surface pathology, however, pIgR appears to be unique to SS. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Ocular damage effects from 1338-nm pulsed laser radiation in a rabbit eye model

    PubMed Central

    Jiao, Luguang; Wang, Jiarui; Jing, Xiaomin; Chen, Hongxia; Yang, Zaifu

    2017-01-01

    The ocular damage effects induced by transitional near-infrared (NIR) lasers have been investigated for years. However, no retinal damage thresholds are determined in a wide interval between 0.65 ms and 80 ms, and a definite relationship between corneal damage threshold and spot size cannot be drawn from existing data points. In this paper, the in-vivo corneal damage thresholds (ED50s) were determined in New Zealand white rabbits for a single 5 ms pulse at the wavelength of 1338 nm for spot sizes from 0.28 mm to 3.55 mm. Meanwhile, the retinal damage threshold for this laser was determined in chinchilla grey rabbits under the condition that the beam was collimated, and the incident corneal spot diameter was 5.0 mm. The corneal ED50s given in terms of the corneal radiant exposure for spot diameters of 0.28, 0.94, 1.91, and 3.55 mm were 70.3, 35.6, 29.6 and 30.3 J/cm2, respectively. The retinal ED50 given in terms of total intraocular energy (TIE) was 0.904 J. The most sensitive ocular tissue to this laser changed from the cornea to retina with the increase of spot size. PMID:28663903

  2. Eye-Blink Conditioning Is Associated with Changes in Synaptic Ultrastructure in the Rabbit Interpositus Nuclei

    ERIC Educational Resources Information Center

    Weeks, Andrew C. W.; Connor, Steve; Hinchcliff, Richard; LeBoutillier, Janelle C.; Thompson, Richard F.; Petit, Ted L.

    2007-01-01

    Eye-blink conditioning involves the pairing of a conditioned stimulus (usually a tone) to an unconditioned stimulus (air puff), and it is well established that an intact cerebellum and interpositus nucleus, in particular, are required for this form of classical conditioning. Changes in synaptic number or structure have long been proposed as a…

  3. Eye-Blink Conditioning Is Associated with Changes in Synaptic Ultrastructure in the Rabbit Interpositus Nuclei

    ERIC Educational Resources Information Center

    Weeks, Andrew C. W.; Connor, Steve; Hinchcliff, Richard; LeBoutillier, Janelle C.; Thompson, Richard F.; Petit, Ted L.

    2007-01-01

    Eye-blink conditioning involves the pairing of a conditioned stimulus (usually a tone) to an unconditioned stimulus (air puff), and it is well established that an intact cerebellum and interpositus nucleus, in particular, are required for this form of classical conditioning. Changes in synaptic number or structure have long been proposed as a…

  4. Primary Eye Irritation Potential of DIGL-RP Solid Propellant in Rabbits

    DTIC Science & Technology

    1989-10-01

    observed unaided in a darkened room with focal illuminati ( • ’pen light). Structures examined included: the lids and surrounding fur, the conjuntiva...nictitating membrane) conjunctiva. Conjunctival redness scores of I were assigned to 5 of 5 treated eyes and slit lamp examination confirmed the presence

  5. Comparison of a modified mid-coronal sectioning technique and Wilson's technique when conducting eye and brain examinations in rabbit teratology studies.

    PubMed

    Ziejewski, Mary K; Solomon, Howard M; Rendemonti, Joyce; Stanislaus, Dinesh

    2015-02-01

    There are two methods used when examining fetal rabbit eyes and brain in teratology studies. One method employs prior fixation before serial sectioning (Wilson's technique) and the other uses fresh tissue (mid-coronal sectioning). We modified the mid-coronal sectioning technique to include removal of eyes and brain for closer examination and to increase the number of structures that can be evaluated and compared it to the Wilson's technique. We found that external examination of the head, in conjunction with either sectioning method, is equally sensitive in identifying developmental defects. We evaluated 40,401 New Zealand White (NZW) and Dutch-Belted (DB) rabbit fetuses for external head alterations, of which 28,538 fetuses were further examined for eye and brain alterations using the modified mid-coronal sectioning method (16,675 fetuses) or Wilson's technique (11,863 fetuses). The fetuses were from vehicle control or drug-treated pregnant rabbits in embryo-fetal development studies conducted to meet international regulatory requirements for the development of new drugs. Both methods detected the more common alterations (microphthalmia and dilated lateral cerebral ventricles) and other less common findings (changes in size and/or shape of eye and brain structures). While both methods are equally sensitive at detecting common and rare developmental defects, the modified mid-coronal sectioning technique eliminates the use of chemicals and concomitant fixation artifacts that occur with the Wilson's technique and allows for examination of 100% intact fetuses thereby increasing potential for detecting eye and brain alterations as these findings occur infrequently in rabbits. © 2015 Wiley Periodicals, Inc.

  6. [The effects of a benzopyrone derivative in experimental brain edema due to cold in the rabbit].

    PubMed

    Góngora Castillo, C; Gómez de Segura, I A; López Bravo, A; de Miguel del Campo, E

    1993-01-01

    On this study, parenchymal changes during a cerebral edema caused by thermic injury (cool) on the rabbit, are analyzed. The work was based on the ultrastructural findings obtained by transmission electronic microscopy and on the effects produced by a benzopironic derived (F-117 Hydrosmina). The injury was produced with solid CO2, previous a craniectomy, on the dura mater of the left hemisphere. Forty rabbits were included into the study, the animals were distributed into five groups (n = 8): a control group and 4 treatment groups. One of the groups received treatment without previous cerebral injury. The group of rabbits with doses of 50 mg/Kg of weight showed focal and diffuse areas of edema alternating with less damaged areas, the edema was evident on the white substance. This group also showed a dissociation of the myelinic fibers and an intracytoplasmatic tumefaction into the glial cells. These findings contrast with the histopathological findings obtained from the rabbits (V), the extracellular edema was poor, the myelinic fiber disorganization was minimal with no vacuolar degeneration and no structural mitochondrial changes had been showed. The discontinuance of the hematoencephalic barrier caused by the cool could be a possible mechanism that causes the opening of the endothelial unions from the capillary vessels, changing their membranes and resulting in a free penetration of the molecule into the cerebral parenchyma.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Physiology of aqueous humor dynamic in the anterior chamber due to rapid eye movement.

    PubMed

    Modarreszadeh, SeyedAmirreza; Abouali, Omid; Ghaffarieh, Alireza; Ahmadi, Goodarz

    2014-08-01

    The nature of aqueous humor (AH) mixing in the anterior chamber (AC) of the human eye due to rapid eye movement (REM) has not been fully understood and has been somewhat a controversial issue. This study uses a computational modeling approach to shed light on this issue. For this purpose a numerical method was developed and used to solve the mathematical equations governing the flow and mixing of aqueous humor motion in the eye subjected to such movements. Based on the experimental measurements available in the literature for the average and maximum amplitudes of the eye movements, a harmonic model for the REM was developed. The corresponding instantaneous and time-averaged velocity fields were evaluated. The simulation results showed that, contrary to earlier reports, the REM led to complex flow structures and a 3-D mixing of AH in the anterior chamber. In addition, the mixing velocity increased in direct proportion to the REM amplitudes. Thus, the AC flow generated by REM could carry nutrients to the posterior surface of the cornea during the sleep. Furthermore, the shear stress acting on the corneal endothelial cells due to REM was computed and compared with that of buoyancy driven flow in the AC due to temperature gradient. It was found that the shear stress generated by REM is much higher than that introduced by the natural convection. A video file for providing a better understanding of the AH mixing process in the AC was also prepared. This video is available on the web. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Are Ultrasound-Guided Ophthalmic Blocks Injurious to the Eye? A Comparative Rabbit Model Study of Two Ultrasound Devices Evaluating Intraorbital Thermal and Structural Changes

    PubMed Central

    Palte, Howard D.; Gayer, Steven; Arrieta, Esdras; Shaw, Eric Scot; Nose, Izuru; Lee, Elizabete; Arheart, Kristopher L.; Dubovy, Sander; Birnbach, David J.; Parel, Jean-Marie

    2012-01-01

    Background Since Atkinson’s original description of retrobulbar block in 1936, needle-based anesthetic techniques have become integral to ophthalmic anesthesia. These techniques are unfortunately associated with rare, grave complications such as globe perforation. Ultrasound has gained widespread acceptance for peripheral nerve blockade but its translation to ocular anesthesia has been hampered because sonic energy, in the guise of thermal or biomechanical insult, is potentially injurious to vulnerable eye tissue. The United States Food and Drug Administration have defined guidelines for safe use of ultrasound for ophthalmic examination but most ultrasound devices used by anesthesiologists are not Food and Drug Administration-approved for ocular application because they generate excessive energy. Regulating agencies state that ultrasound examination can be safely undertaken as long as tissue temperatures do not increase >1.5°C above physiological levels. Methods Using a rabbit model, we investigated the thermal and mechanical ocular effects after prolonged ultrasonic exposure to single orbital and non-orbital-rated devices. In a dual-phase study, aimed at detecting ocular injury, the eyes of 8 rabbits were exposed to continuous 10-minute ultrasound examinations from two devices: 1) the Sonosite Micromaxx (non-orbital-rated) and 2) the Sonomed VuMax (orbital-rated) machines. In Phase I temperatures were continuously monitored via thermocouples implanted within specific eye structures (n=4). In Phase II the eyes were subjected to ultrasonic exposure without surgical intervention (n=4). All eyes underwent light microscopy examinations followed, at different intervals, by histology evaluations conducted by an ophthalmic pathologist. Results Temperature changes were monitored in the eyes of four rabbits. The non-orbital-rated transducer produced increases in ocular tissue temperature that surpassed the safe limit (increases> 1.50C ) in the lens of three rabbits (at 5

  9. Are ultrasound-guided ophthalmic blocks injurious to the eye? A comparative rabbit model study of two ultrasound devices evaluating intraorbital thermal and structural changes.

    PubMed

    Palte, Howard D; Gayer, Steven; Arrieta, Esdras; Scot Shaw, Eric; Nose, Izuru; Lee, Elizabete; Arheart, Kristopher L; Dubovy, Sander; Birnbach, David J; Parel, Jean-Marie

    2012-07-01

    Since Atkinson's original description of retrobulbar block in 1936, needle-based anesthetic techniques have become integral to ophthalmic anesthesia. These techniques are unfortunately associated with rare, grave complications such as globe perforation. Ultrasound has gained widespread acceptance for peripheral nerve blockade, but its translation to ocular anesthesia has been hampered because sonic energy, in the guise of thermal or biomechanical insult, is potentially injurious to vulnerable eye tissue. The US Food and Drug Administration (FDA) has defined guidelines for safe use of ultrasound for ophthalmic examination, but most ultrasound devices used by anesthesiologists are not FDA-approved for ocular application because they generate excessive energy. Regulating agencies state that ultrasound examinations can be safely undertaken as long as tissue temperatures do not increase >1.5°C above physiological levels. Using a rabbit model, we investigated the thermal and mechanical ocular effects after prolonged ultrasonic exposure to single orbital- and nonorbital-rated devices. In a dual-phase study, aimed at detecting ocular injury, the eyes of 8 rabbits were exposed to continuous 10-minute ultrasound examinations from 2 devices: (1) the Sonosite Micromaxx (nonorbital rated) and (2) the Sonomed VuMax (orbital rated) machines. In phase I, temperatures were continuously monitored via thermocouples implanted within specific eye structures (n = 4). In phase II the eyes were subjected to ultrasonic exposure without surgical intervention (n = 4). All eyes underwent light microscopy examinations, followed at different intervals by histology evaluations conducted by an ophthalmic pathologist. Temperature changes were monitored in the eyes of 4 rabbits. The nonorbital-rated transducer produced increases in ocular tissue temperature that surpassed the safe limit (increases >1.5°C) in the lens of 3 rabbits (at 5.0, 5.5, and 1.5 minutes) and cornea of 2 rabbits (both at 1

  10. A New Safety Concern for Glaucoma Treatment Demonstrated by Mass Spectrometry Imaging of Benzalkonium Chloride Distribution in the Eye, an Experimental Study in Rabbits

    PubMed Central

    Brignole-Baudouin, Françoise; Desbenoit, Nicolas; Hamm, Gregory; Liang, Hong; Both, Jean-Pierre; Brunelle, Alain; Fournier, Isabelle; Guerineau, Vincent; Legouffe, Raphael; Stauber, Jonathan; Touboul, David; Wisztorski, Maxence; Salzet, Michel; Laprevote, Olivier; Baudouin, Christophe

    2012-01-01

    We investigated in a rabbit model, the eye distribution of topically instilled benzalkonium_(BAK) chloride a commonly used preservative in eye drops using mass spectrometry imaging. Three groups of three New Zealand rabbits each were used: a control one without instillation, one receiving 0.01%BAK twice a day for 5 months and one with 0.2%BAK one drop a day for 1 month. After sacrifice, eyes were embedded and frozen in tragacanth gum. Serial cryosections were alternately deposited on glass slides for histological (hematoxylin-eosin staining) and immunohistological controls (CD45, RLA-DR and vimentin for inflammatory cell infiltration as well as vimentin for Müller glial cell activation) and ITO or stainless steel plates for MSI experiments using Matrix-assisted laser desorption ionization time-of-flight. The MSI results were confirmed by a round-robin study on several adjacent sections conducted in two different laboratories using different sample preparation methods, mass spectrometers and data analysis softwares. BAK was shown to penetrate healthy eyes even after a short duration and was not only detected on the ocular surface structures, but also in deeper tissues, especially in sensitive areas involved in glaucoma pathophysiology, such as the trabecular meshwork and the optic nerve areas, as confirmed by images with histological stainings. CD45-, RLA-DR- and vimentin-positive cells increased in treated eyes. Vimentin was found only in the inner layer of retina in normal eyes and increased in all retinal layers in treated eyes, confirming an activation response to a cell stress. This ocular toxicological study confirms the presence of BAK preservative in ocular surface structures as well as in deeper structures involved in glaucoma disease. The inflammatory cell infiltration and Müller glial cell activation confirmed the deleterious effect of BAK. Although these results were obtained in animals, they highlight the importance of the safety-first principle for

  11. A new safety concern for glaucoma treatment demonstrated by mass spectrometry imaging of benzalkonium chloride distribution in the eye, an experimental study in rabbits.

    PubMed

    Brignole-Baudouin, Françoise; Desbenoit, Nicolas; Hamm, Gregory; Liang, Hong; Both, Jean-Pierre; Brunelle, Alain; Fournier, Isabelle; Guerineau, Vincent; Legouffe, Raphael; Stauber, Jonathan; Touboul, David; Wisztorski, Maxence; Salzet, Michel; Laprevote, Olivier; Baudouin, Christophe

    2012-01-01

    We investigated in a rabbit model, the eye distribution of topically instilled benzalkonium_(BAK) chloride a commonly used preservative in eye drops using mass spectrometry imaging. Three groups of three New Zealand rabbits each were used: a control one without instillation, one receiving 0.01%BAK twice a day for 5 months and one with 0.2%BAK one drop a day for 1 month. After sacrifice, eyes were embedded and frozen in tragacanth gum. Serial cryosections were alternately deposited on glass slides for histological (hematoxylin-eosin staining) and immunohistological controls (CD45, RLA-DR and vimentin for inflammatory cell infiltration as well as vimentin for Müller glial cell activation) and ITO or stainless steel plates for MSI experiments using Matrix-assisted laser desorption ionization time-of-flight. The MSI results were confirmed by a round-robin study on several adjacent sections conducted in two different laboratories using different sample preparation methods, mass spectrometers and data analysis softwares. BAK was shown to penetrate healthy eyes even after a short duration and was not only detected on the ocular surface structures, but also in deeper tissues, especially in sensitive areas involved in glaucoma pathophysiology, such as the trabecular meshwork and the optic nerve areas, as confirmed by images with histological stainings. CD45-, RLA-DR- and vimentin-positive cells increased in treated eyes. Vimentin was found only in the inner layer of retina in normal eyes and increased in all retinal layers in treated eyes, confirming an activation response to a cell stress. This ocular toxicological study confirms the presence of BAK preservative in ocular surface structures as well as in deeper structures involved in glaucoma disease. The inflammatory cell infiltration and Müller glial cell activation confirmed the deleterious effect of BAK. Although these results were obtained in animals, they highlight the importance of the safety-first principle for

  12. Confocal microscopic analysis of a rabbit eye model of high incidence recurrent herpes stromal keratitis (HSK)

    PubMed Central

    Jester, James V.; Morishige, Naoyuki; BenMohamed, Lbachir; Brown, Donald J.; Osorio, Nelson; Hsiang, Chinhui; Perng, Guey Chuen; Jones, Clinton; Wechsler, Steven L.

    2015-01-01

    Purpose Using CJLAT, a chimeric herpes simplex virus (HSV-1) that produces a high incidence of herpes stromal keratitis (HSK) in latently infected rabbits, we characterized, by in vivo confocal microscopy (CM), the cellular events that precede development of HSK. Methods Thirty days post infection, in vivo CM was performed daily for 10 days and then weekly for up to 80 days post infection. Results We detected three types of subclinical corneal lesions prior to clinically apparent HSK: i)Small epithelial erosions; ii)Regenerating epithelium overlying small, cell infiltrates within the basal epithelial cell layer; and iii)Dendritic-like cells within the basal epithelial layer overlying stromal foci containing infiltrating cells. Sequential in vivo CM observations suggested that subclinical foci resolved over time, but were larger and more abundant with CJLAT than wild type HSV-1 McKrae. Active HSK was observed only with CJLAT and was initially associated with a large epithelial lesion overlying stromal immune cell infiltrates. Conclusions These results suggest that replication in the cornea of reactivated virus from trigeminal ganglia produces epithelial lesions which recruit immune cell infiltrates into the basal epithelial layer and anterior stroma. The virus is usually cleared rapidly eliminating viral antigens (Ags) prior to the arrival of the immune cells, which disperse. However, if the virus is not cleared rapidly, or if an additional reactivation results in an additional round of virus at the same site before the immune cells disperse, then the immune cells are stimulated and may induce an immunopathological response leading to the development of HSK. PMID:26555580

  13. Confocal Microscopic Analysis of a Rabbit Eye Model of High-Incidence Recurrent Herpes Stromal Keratitis.

    PubMed

    Jester, James V; Morishige, Naoyuki; BenMohamed, Lbachir; Brown, Donald J; Osorio, Nelson; Hsiang, Chinhui; Perng, Guey Chuen; Jones, Clinton; Wechsler, Steven L

    2016-01-01

    Using CJLAT, a chimeric herpes simplex virus (HSV-1) that produces a high incidence of herpes stromal keratitis (HSK) in latently infected rabbits, and in vivo confocal microscopy (CM), we characterized the cellular events that precede the development of HSK. Thirty days after infection, in vivo CM was performed daily for 10 days and then weekly for up to 80 days after infection. We detected 3 types of subclinical corneal lesions before HSK was clinically apparent: (1) small epithelial erosions; (2) regenerating epithelium overlying small cell infiltrates within the basal epithelial cell layer; and (3) dendritic-like cells within the basal epithelial layer overlying stromal foci containing infiltrating cells. Sequential in vivo CM observations suggested that subclinical foci resolved over time but were larger and more abundant with CJLAT than with wild-type HSV-1 McKrae. Active HSK was observed only with CJLAT and was initially associated with a large epithelial lesion overlying stromal immune cell infiltrates. These results suggest that replication in the cornea of reactivated virus from the trigeminal ganglia produces epithelial lesions, which recruit immune cell infiltrates into the basal epithelial layer and anterior stroma. The virus is usually cleared rapidly eliminating viral antigens before the arrival of the immune cells, which disperse. However, if the virus is not cleared rapidly, or if an additional reactivation results in an additional round of virus at the same site before the immune cells disperse, then the immune cells are stimulated and may induce an immunopathological response leading to the development of HSK.

  14. Selective targeting of the retinal pigment epithelium in rabbit eyes with a scanning laser beam.

    PubMed

    Framme, Carsten; Alt, Clemens; Schnell, Susanne; Sherwood, Margaret; Brinkmann, Ralf; Lin, Charles P

    2007-04-01

    Selective targeting of the retinal pigment epithelium (RPE) with repetitive laser pulses that minimize thermal damage to the adjacent photoreceptors is a promising new therapeutic modality for RPE-related retinal diseases. The selectivity of an alternative, more versatile scanning approach was examined in vivo by using a broad range of scanning parameters. Acousto-optic deflectors repeatedly scanned the focus of a continuous wave (cw)-laser across the retina of Dutch belted rabbits, producing microsecond irradiation at each RPE cell. Two irradiation patterns forming separated lines (SEP) or interlaced lines (INT), different dwell times (2.5-75 micros), and repetition numbers (10 and 100 scans with 100-Hz repetition rate) were tested. Thresholds were evaluated by fundus imaging and angiography. Histology was performed for selected parameters. Selective RPE cell damage was obtained with moderate laser power. The angiographic threshold power decreased with pulse duration, number of exposures, and applying the INT pattern. Ophthalmoscopic thresholds, indicating onset of thermal coagulation, were higher than twice the angiographic threshold for most tested parameters. Histology confirmed selective RPE cell damage for SEP irradiation with 7.5 and 15 micros; slower scan speeds or closed lines caused photoreceptor damage. A cw-laser scanner can be set up as a highly compact and versatile device. Selective RPE damage is feasible with dwell times up to 15 micros. Greatest selectivity is achieved with short exposure times and separated scan lines. Interlaced lines and long exposure times facilitate heat conduction into photoreceptors. A scanner is an attractive alternative for pulsed selective targeting, because both selective targeting and thermal photocoagulation can be realized.

  15. [Combined rapamycin eye drop in nanometer vector and poly (lactic acid) wafers of cyclosporine A effectively prevents high-risk corneal allograft rejection in rabbits].

    PubMed

    Jiang, Wei; Sun, Hui-Min; Li, Xiao-Rong; Yuan, Xu-Bo; Wang, Yu-Qing; Zhang, Shu-Xian; Tian, En-Jiang; Yuan, Jia-Qin

    2009-06-01

    To evaluate the combined effect of topical rapamycin (RAPA) eye drop in nanometer vector and poly (lactic acid) (PLA) wafers of cyclosporine A (CsA) in the prevention of acute allograft rejection after rabbit corneal transplantation. Methods It was an experimental study. RAPA was incorporated into the nanometer particles and CsA was incorporated into PLA wafers. A was syngeneic control whose both donor and recipient are New Zealand rabbit. Gray donor corneas were implanted into the 102 recipients of New Zealand albino rabbits with corneal neovascularization who were randomly divided into B, C, D, E, F, G 6 groups to receive the different types of therapy: B was no therapy control; C was eye drop of nanometer vector but no RAPA twice a day, 28 days; D was PLA wafers in the anterior chamber of rabbit eyes but no drugs; E was 0.5% RAPA eye drop of nanometer vector twice a day, 28 days; F was PLA wafers of CsA in the anterior chamber of rabbit eyes; G was PLA wafers of CsA in the anterior chamber of rabbit eyes and 0.5% RAPA eye drop of nanometer vector eye drop twice a day for 28 days together. Postoperative evaluation included slit-lamp biomicroscopy, histopathology and immunohistology, Cytokines related with neovascularization and immunosuppression in the corneal tissue by RT-PCR. The graft survival was assessed by One-Way ANOVA and q test. Corneal allograft survival time: A (100.00 +/- 0.00), B (8.44 +/- 1.24), C (8.89 +/- 2.57), D (8.56 +/- 2.30), E (43.11 +/- 5.58), F (43.67 +/- 9.54), G (72.00 +/- 15.34) d. Group G led to a statistically significant prolongation of transplant survival and was superior than group E and F which was a statistical prolongation compared with group B, C and D (qGE = 11.42, qGF = 11.24, qEB = 13.64, qEC = 13.38, qED = 13.46, qFB = 13.82, qFC = 13.56, qFD = 13.64; P < 0.01). Immunohistopathologically, the grafts were subjected to an immune response contained a dense infiltrate of neutrophils, CD4+ and CD8+ T lymphocytes in the group B

  16. Fs-lentotomy: first in vivo studies on rabbit eyes with a 100 kHz laser system

    NASA Astrophysics Data System (ADS)

    Schumacher, S.; Oberheide, U.; Fromm, M.; Ertmer, W.; Gerten, G.; Wegener, A.; Lubatschowski, H.

    2008-02-01

    Up to now reading glasses are the conventional treatment of presbyopia, an age related effect for every human. According to the Helmholtz theory the reason for the development of accommodative loss is a decreasing elasticity of the lens due to the increasing sclerosis. Since the ciliary muscle and the lens capsule remain active and elastic the whole life, a possible treatment could be the increase of the flexibility by creating gliding planes with fs-laser pulses. flexibility of ex vivo porcine as well as human donor lenses with a laboratory laser system. We will present new results with a compact 100 kHz repetition rate turn key laser system which speeds up the treatment time by a factor of 10. This will offer the opportunity for future clinical trials. Furthermore first in-vivo results on rabbits are presented.

  17. A substance P antagonist, (D-Pro2, D-Trp7,9)SP, inhibits inflammatory responses in the rabbit eye

    SciTech Connect

    Holmdahl, G.; Hakanson, R.; Leander, S.; Rosell, S.; Folkers, K.; Sundler, F.

    1981-11-27

    Neurogenic factors released by antidromic nerve stimulation are thought to be in part responsible for the vasodilation and breakdown of the blood-aqueous barrier that follows trauma to the eye. Substance P is one candidate for the mediation of the inflammatory response since it is thought to be a neurotransmitter in sensory afferents and since exogenous substance P is capable of eliciting a response characteristic of inflammation. In rabbits, intravitreal or topical application onto the eye of a specific substance P antagonist, (d-Pro2, D-Trp7,9)SP, inhibited not only the irritant effects of exogenous substance P but also the inflammatory response to a standardized trauma (infrared irradiation of the iris). These observations suggest that substance P, or a related peptide, is a neurogenic mediator of the inflammatory response in the eye.

  18. Optic neuropathy and increased retinal glial fibrillary acidic protein due to microbead-induced ocular hypertension in the rabbit

    PubMed Central

    Zhao, Jun; Zhu, Tian-Hui; Chen, Wen-Chieh; Peng, Shi-Ming; Huang, Xiao-Sheng; Cho, Kin-Sang; Chen, Dong Feng; Liu, Guei-Sheung

    2016-01-01

    AIM To characterize whether a glaucoma model with chronic elevation of the intraocular pressure (IOP) was able to be induced by anterior chamber injection of microbeads in rabbits. METHODS In order to screen the optimal dose of microbead injection, IOP was measured every 3d for 4wk using handheld applanation tonometer after a single intracameral injection of 10 µL, 25 µL, 50 µL or 100 µL microbeads (5×106 beads/mL; n=6/group) in New Zealand White rabbits. To prolong IOP elevation, two intracameral injections of 50 µL microbeads or phosphate buffer saline (PBS) were made respectively at days 0 and 21 (n=24/group). The fellow eye was not treated. At 5wk after the second injection of microbeads or PBS, bright-field microscopy and transmission electron microscopy (TEM) were used to assess the changes in the retina. The expression of glial fibrillary acidic protein (GFAP) in the retina was evaluated by immunofluorescence, quantitative real-time polymerase chain reaction and Western blot at 5wk after the second injection of microbeads. RESULTS Following a single intracameral injection of 10 µL, 25 µL, 50 µL or 100 µL microbead, IOP levels showed a gradual increase and a later decrease over a 4wk period after a single injection of microbead into the anterior chamber of rabbits. A peak IOP was observed at day 15 after injection. No significant difference in peak value of IOP was found between 10 µL and 25 µL groups (17.13±1.25 mm Hg vs 17.63±0.74 mm Hg; P=0.346). The peak value of IOP from 50 µL group (23.25±1.16 mm Hg) was significantly higher than 10 µL and 25 µL groups (all P<0.05). Administration of 100 µL microbead solution (23.00±0.93 mm Hg) did not lead to a significant increase in IOP compared to the 50 µL group (P=0.64). A prolonged elevated IOP duration up to 8wk was achieved by administering two injections of 50 µL microbeads (20.48±1.21 mm Hg vs 13.60±0.90 mm Hg in PBS-injected group; P<0.05). The bright-field and TEM were used to assess

  19. Lateral asymmetries due to preferences in eye use during visual discrimination learning in chicks.

    PubMed

    Vallortigara, G; Regolin, L; Bortolomiol, G; Tommasi, L

    1996-01-01

    Chicks were trained to discriminate between two boxes of the same colour (white) on the basis of their positions using the pecking response. Some chicks were trained to peck at the box on their right side, some at the box on their left side. They were then retrained with two boxes of different colours (one red the other green): in one group of chicks the position of the two boxes was randomly alternated in the various trials (thus making colour a conspicuous but irrelevant cue), in the other it was maintained unchanged. A control group was retrained with two white boxes identical to those used during training. In all of the three groups chicks had to discriminate between the two boxes on the basis of their positions. During training, chicks took less trial and errors to learn when the positive box was placed on their right side and the same occurred during retraining with boxes that maintained a fixed position and during retraining in the control condition. During retraining with position alternation, on the contrary, chicks took less trials and errors to learn when the positive box was placed on their left side. Video recording of the chicks' behaviour while approaching the boxes showed that these lateral asymmetries reflect head and body turning associated to preferences in eye use, likely due to the different specializations of contralateral brain structures. It is argued that position cues engage the right hemisphere, with consequent head turning to the right to allow lateral viewing by the left eye; object-specific cues engage the left hemisphere, with consequent head turning to the left to allow lateral viewing by the right eye.

  20. Comparison of the effects of various lubricant eye drops on the in vitro rabbit corneal healing and toxicity.

    PubMed

    Dutescu, R Michael; Panfil, Claudia; Schrage, Norbert

    2017-03-02

    Ingredients of lubricant eye drops are potentially harmful to the ocular surface. The products Optive, Optive Fusion, Neopt were tested regarding corneal irritability versus Vismed Multi and 0.01% benzalkonium chloride as negative and positive control, respectively. Formulas (30-40μl per hour) were applied hourly in-vitro for six days on rabbit corneas (n=5, per product) cultured in artificial anterior chambers (EVEIT system). Initially, four corneal abrasions (2.4-4.6mm(2)) were induced. All defects were monitored during drop application by fluorescein stains and photographs. To ensure corneal vitality, glucose and lactate concentrations in artificial anterior chamber fluids were determined photometrically. All products showed a complete corneal healing on day 2. Thereafter, all five Optive-treated corneas developed progressive fluorescein-positive epithelial lesions until day six (24.96μm, ±21.45μm, p<0.01). For Optive Fusion three corneas showed corneal erosions on day six (23.11μm, ±37.02μm, p>0.5) while Vismed Multi did not adversely affect the corneal integrity. Glucose/lactate concentrations remained unchanged while lubricants were applied. Histology revealed epithelial loss and severe alterations of the superficial stroma for Optive. Optive Fusion displayed a comparable pathology. Neopt did not significantly affect the corneal healing and integrity. This study suggested a cumulative corneal toxicity of Optive and, to a lesser extent, Optive Fusion most likely caused by its oxidative preservative, SOC. Clinical data are needed to clarify the application frequency at which corneal toxicity might occur. Neopt and Vismed Multi did not affect the corneal integrity. Copyright © 2016 Elsevier GmbH. All rights reserved.

  1. Suprachoroidal delivery in a rabbit ex vivo eye model: influence of drug properties, regional differences in delivery, and comparison with intravitreal and intracameral routes

    PubMed Central

    Kadam, Rajendra S.; Williams, Jason; Tyagi, Puneet; Edelhauser, Henry F.

    2013-01-01

    Purpose First, to determine the influence of drug lipophilicity (using eight beta-blockers) and molecular weight (using 4 kDa and 40 kDa fluoroscein isothiocyanate [FITC]-dextrans) on suprachoroidal delivery to the posterior segment of the eye by using a rabbit ex vivo eye model. Second, to determine whether drug distribution differs between the dosed and undosed side of the eye following suprachoroidal delivery. Third, to compare the suprachoroidal delivery of sodium fluorescein (NaF) with the intracameral and intravitreal routes by using noninvasive fluorophotometry. Methods Using a small hypodermic 26G needle (3/8”) with a short bevel (250 µm), location of the suprachoroidal injection in an ex vivo New Zealand white rabbit eye model was confirmed with India ink. Ocular tissue distribution of NaF (25 µl of 1.5 µg/ml) at 37 °C was monitored noninvasively using the Fluorotron MasterTM at 0, 1, and 3 h following suprachoroidal, intravitreal, or intracameral injections in ex vivo rabbit eyes. For assessing the influence of lipophilicity and molecular size, 25 µl of a mixture of eight beta-blockers (250 µg/ml each) or FITC-dextran (4 kDa and 40 kDa, 30 mg/ml) was injected into the suprachoroidal space of excised rabbit eyes and incubated at 37 °C. Eyes were incubated for 1 and 3 h, and frozen at the end of incubation. Ocular tissues were isolated in frozen condition. Beta-blocker and FITC-dextran levels in excised ocular tissue were measured by liquid chromatography–tandem mass spectrometry and spectrofluorometry, respectively. Results Histological sections of India ink-injected albino rabbit eye showed the localization of dye as a black line in the suprachoroidal space. Suprachoroidal injection of NaF showed signal localization to the choroid and retina at 1 and 3 h post injection when compared with intravitreal and intracameral injections. Drug delivery to the vitreous after suprachoroidal injection decreased with an increase in solute lipophilicity

  2. Gentamicin-Loaded Borate Bioactive Glass Eradicates Osteomyelitis Due to Escherichia coli in a Rabbit Model

    PubMed Central

    Xie, Zongping; Cui, Xu; Zhao, Cunju; Huang, Wenhai; Wang, Jianqiang

    2013-01-01

    The treatment of osteomyelitis induced by Gram-negative bacilli is rarely reported in the literature. This study established a rabbit tibia model of osteomyelitis induced by the Gram-negative bacillus Escherichia coli. Using this model, pellets composed of a chitosan-bonded mixture of borate bioactive glass and gentamicin were evaluated in vitro and in vivo for the treatment of osteomyelitis induced by Escherichia coli. Our results showed that the pellets in phosphate-buffered saline released gentamicin continuously over 26 days. Without the simultaneous use of a systemic antibiotic, the implantation of the gentamicin-loaded pellets into the osteomyelitis region of the tibia resulted in the eradication of 81.82% of infections, as determined by microbiological, histological and radiographic evaluation, and supported the ingrowth of new bone into the tibia defects after 6 weeks of implantation. The results indicate that the gentamicin-loaded borate bioactive glass implant, combining sustained drug release with the ability to support new bone formation, could provide a method for treating osteomyelitis induced by Gram-negative bacilli. PMID:23629702

  3. Gentamicin-loaded borate bioactive glass eradicates osteomyelitis due to Escherichia coli in a rabbit model.

    PubMed

    Xie, Zongping; Cui, Xu; Zhao, Cunju; Huang, Wenhai; Wang, Jianqiang; Zhang, Changqing

    2013-07-01

    The treatment of osteomyelitis induced by Gram-negative bacilli is rarely reported in the literature. This study established a rabbit tibia model of osteomyelitis induced by the Gram-negative bacillus Escherichia coli. Using this model, pellets composed of a chitosan-bonded mixture of borate bioactive glass and gentamicin were evaluated in vitro and in vivo for the treatment of osteomyelitis induced by Escherichia coli. Our results showed that the pellets in phosphate-buffered saline released gentamicin continuously over 26 days. Without the simultaneous use of a systemic antibiotic, the implantation of the gentamicin-loaded pellets into the osteomyelitis region of the tibia resulted in the eradication of 81.82% of infections, as determined by microbiological, histological and radiographic evaluation, and supported the ingrowth of new bone into the tibia defects after 6 weeks of implantation. The results indicate that the gentamicin-loaded borate bioactive glass implant, combining sustained drug release with the ability to support new bone formation, could provide a method for treating osteomyelitis induced by Gram-negative bacilli.

  4. Penetrating and Intrastromal Corneal Arcuate Incisions in Rabbit and Human Cadaver Eyes: Manual Diamond Blade and Femtosecond Laser-Created Incisions.

    PubMed

    Gray, Brad; Binder, Perry S; Huang, Ling C; Hill, Jim; Salvador-Silva, Mercedes; Gwon, Arlene

    2016-07-01

    To compare morphologic differences between freehand diamond or femtosecond laser-assisted penetrating and intrastromal arcuate incisions. Freehand diamond blade, corneal arcuate incisions (180° apart, 60° arc lengths) and 150 kHz femtosecond laser (80% scheimpflug pachymetry depth corneal thickness) arcuate incisions were performed in rabbits. Intrastromal arcuate incisions (100 μm above Descemet's membrane, 100 μm below epithelium) were performed in rabbit corneas (energy 1.2 μJ, spot line separation 3 × 3 μm, 90° side cut angle). Eyes were examined by slit lamp and light microscopy up to 47 days post-procedure. Freehand diamond blade penetrating incisions, and femtosecond laser penetrating and intrastromal arcuate incisions (energy 1.8 μJ, spot line separation 2 × 2 μm) were performed in cadaver eyes. Optical coherence tomography was performed immediately after surgery and the corneas were fixed for light scanning and transmission electron microscopy. The rabbit model showed anterior stromal inflammation with epithelial hyperplasia in penetrating blade and laser penetrating wounds. The laser intrastromal and penetrating incisions showed localized constriction of the stromal layers of the cornea near the wound. In cadaver eyes, penetrating wound morphology was similar between blade and laser whereas intrastromal wounds did not affect the cornea above or below incisions. Penetrating femtosecond laser arcuate incisions have more predictable and controlled outcomes shown by less post-operative scarring than incisions performed with a diamond blade. Intrastromal incisions do not affect uncut corneal layers as demonstrated by histopathology. The femtosecond laser has significant advantages in its ability to make intrastromal incisions which are not achievable by traditional freehand or mechanical diamond blades.

  5. Evaluation of photodynamically induced damage to healthy eye tissues of rabbits using the second-generation photosensitizers bacteriochlorin a and mTHPC

    NASA Astrophysics Data System (ADS)

    Schuitmaker, Hans J.; Barthen, Ed; Keunen, Jan E.; Ms Wolff-Rouendaal, Didi

    1999-02-01

    Immediate illumination after sensitizer administration is currently often applied in PDT-trials in ophthalmology. The extent of possible damage to healthy ocular tissue after i.v. administration of the photosensitizers bacteriochlorin a (BCA) or mesa (tetrahydroxyphenyl) chlorin (mTHPC) and subsequent illumination with light of the appropriate wavelength and dose was assessed in rabbit eyes. Both hydrophobic drugs were formulated in 30% polyethylene glycol, 20% ethanol and 50% water to obtain an iv injectable suspension. Rabbits destined for BCA-PDT received a single dose of 10 mg/kg.bw. Rabbits destined for mTHPC-PDT received a dose of 0.3 mg/kg.bw. BCA- treated animals were illuminated immediately and 1, 2 and three hours after administration of the dye with an experimental Philips laser diode (760 nm, c.w., 100 mW/cm2, 100 J). To illuminate the eyes of the mTHPC- treated animals a Krypton laser was used (648 nm, c.w., 100 mW/cm2, 20 J). Illumination of these animals was performed immediately, 24, 48 and 72 hours after administration of the dye. BCA or mTHPC without illumination or illumination without administration of a sensitizing dye did not affect normal ocular tissues as judged by histology. Illumination of the entire eye of BCA-treated animals, immediately after administration of the dye caused a lesion in the macula area with a diameter of 3 mm. At the lesion side the photoreceptors were destroyed, ganglion cells were swollen and the sclera was affected. No skin photosensitivity was observed at anytime. Skin photosensitivity was observed in animals treated with mTHPC. Illumination caused swollen eyelids in all animals except when performed immediately after dye administration.

  6. Acute exposure of rabbit eyes to artificial light in vivo: effect on corneal and third eyelid conjunctival histology and the gene expression of PAFR.

    PubMed

    Varsamidou, Efterpi; Markopoulou, Soultana; Karayannopoulou, Georgia; Kalpatsanidis, Antonis; Kokkas, Vassileios; Karampatakis, Vassileios; Goulas, Antonis

    2014-05-01

    To study the effect of acute exposure of rabbit eyes to artificial sunlight in vivo, on the integrity of corneal and conjunctival tissue as well as on the gene expression of the receptor for platelet activating factor (PAFR). New Zealand albino rabbits were immobilized opposite a 300 W Osram Ultra-Vitalux® light bulb with an emission radiation spectrum similar to that of normal sunlight at noon, and exposed to ultraviolet B radiation in the range of the reported threshold for corneal damage. Corneal and third eyelid tissue samples were removed from exposed eyes at 2, 6 and 24 h following the end of the exposure to the bulb light and were subsequently processed for histochemical staining and RNA extraction. The gene expression of PAFR was detected with real time reverse transcription polymerase chain reaction. Some epithelial shedding was detected in the corneal tissue as a result of acute exposure to artificial sunlight. In the eyelid conjunctiva, a marked accumulation of eosinophils was noticed, as early as 2 h post-exposure, apparently directed toward the upper part of the epithelial layer. This effect appears to subside by hour 24. No statistically significant changes in gene expression were detected in the corneal tissue, whereas in the third eyelid, PAFR gene expression was significantly induced, most prominently at t = 2 and 6 h post-exposure. Acute exposure of rabbit eyes to artificial sunlight induced a marked infiltration of eosinophils into the epithelial layer of the conjunctiva but no gross alterations in the cornea or the third eyelid. The gene expression of PAFR was upregulated, as an effect of light exposure, in the third eyelid but not in the cornea.

  7. Study on the Protective Effect of a New Manganese Superoxide Dismutase on the Microvilli of Rabbit Eyes Exposed to UV Radiation

    PubMed Central

    Grumetto, Lucia; Del Prete, Antonio; Ortosecco, Giovanni; Barbato, Francesco; Del Prete, Salvatore; Borrelli, Antonella; Schiattarella, Antonella; Mancini, Roberto; Mancini, Aldo

    2015-01-01

    We present a study on the protective effects against UV radiation of a gel formulation containing a new recombinant form of manganese superoxide dismutase on the conjunctiva and corneal epithelia of rabbit eyes. The integrity of the microvilli of both ocular tissues has been considered as an indicator of the health of the tissues. Samples, collected by impression cytology technique, were added of 80 µL of a gel formulation containing superoxide dismutase (2.0 µg/mL) and irradiated with UV rays for 30 minutes and were evaluated with scanning electron microscopy. Wilcoxon test was used to verify the possible occurrence of statistically significant differences between damage for treated and nontreated tissues. Application of gel produces a significant reduction of damage by UV irradiation of ocular epithelia; both epithelia present a significant reduction of damaged microvilli number if treated with the superoxide dismutase gel formulation: the p values (differences between damage found for treated and nontreated both ocular tissues) for conjunctiva and cornea samples were p ≪ 0.01 and p ≪ 0.0001, respectively, at confidence level of 95%. The administration of this gel formulation before UV exposure plays a considerable protective role in ocular tissues of rabbit eye with a significant reduction of the damage. PMID:26064973

  8. Study on the Protective Effect of a New Manganese Superoxide Dismutase on the Microvilli of Rabbit Eyes Exposed to UV Radiation.

    PubMed

    Grumetto, Lucia; Del Prete, Antonio; Ortosecco, Giovanni; Barbato, Francesco; Del Prete, Salvatore; Borrelli, Antonella; Schiattarella, Antonella; Mancini, Roberto; Mancini, Aldo

    2015-01-01

    We present a study on the protective effects against UV radiation of a gel formulation containing a new recombinant form of manganese superoxide dismutase on the conjunctiva and corneal epithelia of rabbit eyes. The integrity of the microvilli of both ocular tissues has been considered as an indicator of the health of the tissues. Samples, collected by impression cytology technique, were added of 80 µL of a gel formulation containing superoxide dismutase (2.0 µg/mL) and irradiated with UV rays for 30 minutes and were evaluated with scanning electron microscopy. Wilcoxon test was used to verify the possible occurrence of statistically significant differences between damage for treated and nontreated tissues. Application of gel produces a significant reduction of damage by UV irradiation of ocular epithelia; both epithelia present a significant reduction of damaged microvilli number if treated with the superoxide dismutase gel formulation: the p values (differences between damage found for treated and nontreated both ocular tissues) for conjunctiva and cornea samples were p ≪ 0.01 and p ≪ 0.0001, respectively, at confidence level of 95%. The administration of this gel formulation before UV exposure plays a considerable protective role in ocular tissues of rabbit eye with a significant reduction of the damage.

  9. Neonatal neurobehavior and diffusion MRI changes in brain reorganization due to intrauterine growth restriction in a rabbit model.

    PubMed

    Eixarch, Elisenda; Batalle, Dafnis; Illa, Miriam; Muñoz-Moreno, Emma; Arbat-Plana, Ariadna; Amat-Roldan, Ivan; Figueras, Francesc; Gratacos, Eduard

    2012-01-01

    Intrauterine growth restriction (IUGR) affects 5-10% of all newborns and is associated with a high risk of abnormal neurodevelopment. The timing and patterns of brain reorganization underlying IUGR are poorly documented. We developed a rabbit model of IUGR allowing neonatal neurobehavioral assessment and high resolution brain diffusion magnetic resonance imaging (MRI). The aim of the study was to describe the pattern and functional correlates of fetal brain reorganization induced by IUGR. IUGR was induced in 10 New Zealand fetal rabbits by ligation of 40-50% of uteroplacental vessels in one horn at 25 days of gestation. Ten contralateral horn fetuses were used as controls. Cesarean section was performed at 30 days (term 31 days). At postnatal day +1, neonates were assessed by validated neurobehavioral tests including evaluation of tone, spontaneous locomotion, reflex motor activity, motor responses to olfactory stimuli, and coordination of suck and swallow. Subsequently, brains were collected and fixed and MRI was performed using a high resolution acquisition scheme. Global and regional (manual delineation and voxel based analysis) diffusion tensor imaging parameters were analyzed. IUGR was associated with significantly poorer neurobehavioral performance in most domains. Voxel based analysis revealed fractional anisotropy (FA) differences in multiple brain regions of gray and white matter, including frontal, insular, occipital and temporal cortex, hippocampus, putamen, thalamus, claustrum, medial septal nucleus, anterior commissure, internal capsule, fimbria of hippocampus, medial lemniscus and olfactory tract. Regional FA changes were correlated with poorer outcome in neurobehavioral tests. IUGR is associated with a complex pattern of brain reorganization already at birth, which may open opportunities for early intervention. Diffusion MRI can offer suitable imaging biomarkers to characterize and monitor brain reorganization due to fetal diseases.

  10. Neonatal Neurobehavior and Diffusion MRI Changes in Brain Reorganization Due to Intrauterine Growth Restriction in a Rabbit Model

    PubMed Central

    Eixarch, Elisenda; Batalle, Dafnis; Illa, Miriam; Muñoz-Moreno, Emma; Arbat-Plana, Ariadna; Amat-Roldan, Ivan; Figueras, Francesc; Gratacos, Eduard

    2012-01-01

    Background Intrauterine growth restriction (IUGR) affects 5–10% of all newborns and is associated with a high risk of abnormal neurodevelopment. The timing and patterns of brain reorganization underlying IUGR are poorly documented. We developed a rabbit model of IUGR allowing neonatal neurobehavioral assessment and high resolution brain diffusion magnetic resonance imaging (MRI). The aim of the study was to describe the pattern and functional correlates of fetal brain reorganization induced by IUGR. Methodology/Principal Findings IUGR was induced in 10 New Zealand fetal rabbits by ligation of 40–50% of uteroplacental vessels in one horn at 25 days of gestation. Ten contralateral horn fetuses were used as controls. Cesarean section was performed at 30 days (term 31 days). At postnatal day +1, neonates were assessed by validated neurobehavioral tests including evaluation of tone, spontaneous locomotion, reflex motor activity, motor responses to olfactory stimuli, and coordination of suck and swallow. Subsequently, brains were collected and fixed and MRI was performed using a high resolution acquisition scheme. Global and regional (manual delineation and voxel based analysis) diffusion tensor imaging parameters were analyzed. IUGR was associated with significantly poorer neurobehavioral performance in most domains. Voxel based analysis revealed fractional anisotropy (FA) differences in multiple brain regions of gray and white matter, including frontal, insular, occipital and temporal cortex, hippocampus, putamen, thalamus, claustrum, medial septal nucleus, anterior commissure, internal capsule, fimbria of hippocampus, medial lemniscus and olfactory tract. Regional FA changes were correlated with poorer outcome in neurobehavioral tests. Conclusions IUGR is associated with a complex pattern of brain reorganization already at birth, which may open opportunities for early intervention. Diffusion MRI can offer suitable imaging biomarkers to characterize and monitor

  11. Comparison of 1% cyclosporine eye drops in olive oil and in linseed oil to treat experimentally-induced keratoconjunctivitis sicca in rabbits.

    PubMed

    Parrilha, Leticia Rodrigues; Nai, Gisele Alborghetti; Giuffrida, Rogério; Barbero, Rafael Cabral; Padovani, Leticia Dias Fabris; Pereira, Ricardo Henrique Zaquir; Silva, Danielle Alves; Silva, Mariele Catherine Alves; Diniz, Miriely Stein; Andrade, Silvia Franco

    2015-01-01

    To evaluate the effectiveness of topical 1% cyclosporine eye drops diluted in either of the two vehicles-olive and linseed oil-and that of the oils themselves in treating experimentally-induced keratoconjunctivitis sicca (KCS) in rabbits. KCS was induced in 25 New Zealand rabbits using 1% atropine sulfate eye drops for 7 days before treatment and throughout the treatment period (12 weeks). The rabbits were divided into five groups: one control (C) group without KCS induction and four treatment groups in which KCS was induced and treated topically with olive oil (O), linseed oil (L), cyclosporine in olive oil (CO), and cyclosporine in linseed oil (CL). The animals were evaluated using Schirmer tear test 1 (STT), the fluorescein test (FT), tear-film break-up time (TBUT), the rose bengal test (RBT), and histopathological analysis. Values of STT and TBUT significantly decreased 1 week post-induction (p<0.05) and were similar to initial values after the 4th week of treatment, in all groups. After KCS induction, there was significantly less corneal damage in group L than in group CL, as assessed FT and RBT. Histopathology demonstrated that Groups L and CL presented less edema and corneal congestion. There was no significant difference in the goblet cell density (cells/mm2) between the groups (p=0.147). Cyclosporine diluted in olive oil or linseed oil was effective in the treatment of KCS, although it had better efficacy when diluted in linseed oil. Linseed oil presented better effectiveness, whether associated or not, than olive oil. These results may contribute to the creation of novel topical ophthalmic formulations for KCS treatment in future.

  12. Thermal cataract formation in rabbits

    SciTech Connect

    Kramar, P.; Harris, C.; Guy, A.W.

    1987-01-01

    Intraocularly circulating hot water was used to produce cataracts in nine eyes of seven rabbits by maintaining their retrolental temperatures between 43 degrees C and 45 degrees C. A rapid rate of heating (1.3 degrees C/min) plus a sharp temperature gradient across the eye may have been contributing factors in the consistent production of cataracts at these temperatures. Biomicroscopy and light microscopy showed lens changes similar to those associated with acute exposure to microwave radiation. These findings support the assumption that microwave cataractogenesis is due to the local production of elevated temperatures.

  13. Exploration and comparison of in vitro eye irritation tests with the ISO standard in vivo rabbit test for the evaluation of the ocular irritancy of contact lenses.

    PubMed

    Yun, Jun-Won; Hailian, Quan; Na, Yirang; Kang, Byeong-Cheol; Yoon, Jung-Hee; Cho, Eun-Young; Lee, Miri; Kim, Da-Eun; Bae, SeungJin; Seok, Seung Hyeok; Lim, Kyung-Min

    2016-12-01

    In an effort to explore the use of alternative methods to animal testing for the evaluation of the ocular irritancy of medical devices, we evaluated representative contact lenses with the bovine corneal opacity and permeability test (BCOP) and an in vitro eye irritation test using the three-dimensionally-reconstructed human corneal epithelium (RhCE) models, EpiOcular™ and MCTT HCE™. In addition, we compared the obtained results with the ISO standard in vivo rabbit eye irritation test (ISO10993-10). Along with the positive controls (benzalkonium chloride, BAK, 0.02, 0.2, and 1%), the extracts of 4 representative contact lenses (soft, disposable, hard, and colored lenses) and 2 reference lenses (dye-eluting and BAK-coated lenses) were tested. All the lenses, except for the BAK-coated lens, were determined non-irritants in all test methods, while the positive controls yielded relevant results. More importantly, BCOP, EpiOcular™, and MCTT HCE™ yielded a consistent decision for all the tested samples, with the exception of 0.2% BAK in BCOP, for which no prediction could be made. Overall, all the in vitro tests correlated well with the in vivo rabbit eye irritation test, and furthermore, the combination of in vitro tests as a tiered testing strategy was able to produce results similar to those seen in vivo. These observations suggest that such methods can be used as alternative assays to replace the conventional in vivo test method in the evaluation of the ocular irritancy of ophthalmic medical devices, although further study is necessary. Copyright © 2016. Published by Elsevier Ltd.

  14. [Influence of mechanical effect due to MRI-magnet on tattoo seal and eye makeup].

    PubMed

    Morishita, Yuta; Miyati, Tosiaki; Ueda, Jousei; Shimizu, Mitsuru; Hamaguchi, Takashi; Fujiwara, Yasuhiro; Hayashi, Hiroyuki

    2008-05-20

    The purpose of our study was to assess the mechanical effect on tattoo seals and eye makeup caused by a spatial magnetic gradient in the magnetic resonance imaging (MRI) system. Seven kinds of tattoo seals and three kinds of eye makeup, i.e., mascara, eye shadow, and eyeliner were used. On a 3.0-Tesla MRI, we determined these deflection angles according to a method established by the American Society for Testing and Materials (ASTM) at the position that produced the greatest magnetically induced deflection. Eighty-five percent of the tattoo seals showed deflection angles greater than 45 degrees of the ASTM guidelines, and the mascara and eye shadow showed over 40 degrees. This was because these contained ferromagnetic pigments such as an iron oxide, but those translational forces were very small owing to slight mass. However, it is desirable that these should be removed before MRI examination to prevent secondary problems.

  15. Binocular fusion and invariant category learning due to predictive remapping during scanning of a depthful scene with eye movements

    PubMed Central

    Grossberg, Stephen; Srinivasan, Karthik; Yazdanbakhsh, Arash

    2015-01-01

    How does the brain maintain stable fusion of 3D scenes when the eyes move? Every eye movement causes each retinal position to process a different set of scenic features, and thus the brain needs to binocularly fuse new combinations of features at each position after an eye movement. Despite these breaks in retinotopic fusion due to each movement, previously fused representations of a scene in depth often appear stable. The 3D ARTSCAN neural model proposes how the brain does this by unifying concepts about how multiple cortical areas in the What and Where cortical streams interact to coordinate processes of 3D boundary and surface perception, spatial attention, invariant object category learning, predictive remapping, eye movement control, and learned coordinate transformations. The model explains data from single neuron and psychophysical studies of covert visual attention shifts prior to eye movements. The model further clarifies how perceptual, attentional, and cognitive interactions among multiple brain regions (LGN, V1, V2, V3A, V4, MT, MST, PPC, LIP, ITp, ITa, SC) may accomplish predictive remapping as part of the process whereby view-invariant object categories are learned. These results build upon earlier neural models of 3D vision and figure-ground separation and the learning of invariant object categories as the eyes freely scan a scene. A key process concerns how an object's surface representation generates a form-fitting distribution of spatial attention, or attentional shroud, in parietal cortex that helps maintain the stability of multiple perceptual and cognitive processes. Predictive eye movement signals maintain the stability of the shroud, as well as of binocularly fused perceptual boundaries and surface representations. PMID:25642198

  16. [A Case of Corneal Injury due to Herbicide Containing Paraquat: Effectiveness of 2% Rebamipide Eye Drops].

    PubMed

    Uno, Makoto

    2015-08-01

    Herbicides containing paraquat are widely used and have occasionally been causing ocular damage. The initial ocular injury caused by paraquat tends to worsen within a few days to 1 week. The toxicity of paraquat is based on the oxidative stress induced by reactive oxygen species. An 82-year-old woman who had been exposed to herbicide containing paraquat in her left eye presented at Koumeikan Eye Clinic 2 days after the incident. Moderate corneal erosion was diagnosed and treated with ordinary medication, but the corneal lesion worsened. After administration of topical 2% rebamipide eye drops, the corneal lesion resolved rapidly. Because of its role as a radical scavenger, rebamipide has great potential for treatment of corneal injuries caused by herbicides such as paraquat.

  17. Postoperative endophthalmitis due to Burkholderia cepacia complex from contaminated anaesthetic eye drops.

    PubMed

    Lalitha, Prajna; Das, Manoranjan; Purva, Patwari S; Karpagam, Rajaratinam; Geetha, Manoharan; Lakshmi Priya, Jeganathan; Naresh Babu, Kannan

    2014-11-01

    To report the clinical presentation and outcomes of cluster postcataract Burkholderia cepacia complex endophthalmitis, the source of infection and clonal relatedness of the isolates. This was a retrospective study on 13 patients who developed acute postoperative endophthalmitis, along with an infiltrate at the corneal section, after an uneventful cataract surgery with intraocular lens implantation. Aqueous aspirates, vitreous aspirates and environmental surveillance specimens were sampled. Genotypic diversity was determined by PCR using BOX-PCR for each strain, and the clonal relationship was established between clinical and eye drops isolates. Vitreous samples showed B. cepacia in cultures in all 13 eyes. Among the samples from various surveillance specimens cultured, topical anaesthetic eye drops grew B. cepacia. The isolates from the patients and the eye drops solution revealed matching banding patterns in BOX-PCR. Isolates from the patients and eye drops were susceptible to cefotaxime and piperacillin/tazobactam only. 9 (69%) patients out of 13 had a final visual acuity of 6/60 or better. Among the remaining four patients, three had a vision of perception of light and one had final vision of 1/60. Microbiology culture and BOX-PCR results revealed contamination of local anaesthetic eye drops and the same organism was cultured from a group of patients with acute-onset postoperative endophthalmitis after an uneventful cataract surgery. Outbreaks may occur in the most vigilant settings, and any sterile consumable may be a common link. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. Characterization of the pH and Temperature in the Rabbit, Pig, and Monkey Eye: Key Parameters for the Development of Long-Acting Delivery Ocular Strategies.

    PubMed

    Lorget, Florence; Parenteau, Audrey; Carrier, Michel; Lambert, Daniel; Gueorguieva, Ana; Schuetz, Chris; Bantseev, Vlad; Thackaberry, Evan

    2016-09-06

    Many long-acting delivery strategies for ocular indications rely on pH- and/or temperature-driven release of the therapeutic agent and degradation of the drug carrier. Yet, these physiological parameters are poorly characterized in ocular animal models. These strategies aim at reducing the frequency of dosing, which is of particular interest for the treatment of chronic disorders affecting the posterior segment of the eye, such as macular degeneration that warrants monthly or every other month intravitreal injections. We used anesthetized white New Zealand rabbits, Yucatan mini pigs, and cynomolgus monkeys to characterize pH and temperature in several vitreous locations and the central aqueous location. We also established post mortem pH changes in the vitreous. Our data showed regional and species differences, which need to be factored into strategies for developing biodegradable long-acting delivery systems.

  19. The effect of autologous serum eye drops on the conjunctivalization over exposed porous polyethylene orbital implant (Medpor(®)) in the rabbit model.

    PubMed

    Kim, Joo Hoon; Chung, Ho Kyung; Kim, Nam Ju; Lee, Min Joung; Khwarg, Sang In

    2011-03-01

    To assess the efficacy of autologous serum eye drops (AS) in enhancing conjunctivalization over a scleral patch graft on exposed porous polyethylene orbital implant (Medpor(®)). Eighteen rabbits were underwent evisceration, implantation of Medpor(®) and homologous scleral patch graft. The conjunctival edge was sutured leaving 5 mm-diameter circular defect. In group A, 20% AS were applied 8 times a day and only balanced salt solution was applied in group B. Digital anterior segment photography was obtained 1, 3, 7, 10, 14, and 21 days after surgery and analyzed with Image Pro Plus(®) software. In the early postoperative period, the average conjunctival growth rate (mm(2)/day) was faster in group A, but failed to show statistical significance (3.79 vs. 3.03, p = 0.26 in 1~3days, 2.39 vs. 1.80, p = 0.59 in 4- days, 0.03 vs. -0.02, p = 0.94 in 7-10 days, Mann-Whitney test). The complete healing rate was higher (67% vs. 56%, p = 0.5, Fisher's exact test) and the mean elapsed time for complete healing (days) was shorter in group A (17.3 vs. 18.2, p  = 0.83, Mann-Whitney test), but did not show a statistically significant difference. In a rabbit model, 20% AS did not appear to facilitate the healing of small conjunctival defects of exposed porous orbital implant.

  20. Hydrocaffeic and p-coumaric acids, natural phenolic compounds, inhibit UV-B damage in WKD human conjunctival cells in vitro and rabbit eye in vivo.

    PubMed

    Larrosa, Mar; Lodovici, Maura; Morbidelli, Lucia; Dolara, Piero

    2008-10-01

    This paper studied the effect on UV-B ocular damage of 10microM hydrocaffeic acid (HCAF) alone and as a mixture (MIX) (5 microM HCAF+5 microM p-coumaric acid). Since ocular UV-B damage is mediated by reactive oxygen species, the aim was to test if HCAF and MIX could reduce oxidation damage in human conjunctival cells (WKD) in vitro and in cornea and sclera of rabbits in vivo. After UVB irradiation (44 J/m(2)) of WKD cells, 8-oxodG levels in DNA were markedly increased and this effect was attenuated by HCAF and MIX. Rabbit eyes were treated by application of HCAF and MIX drops before UV-B exposure (79 J/m(2)). Corneal and scleral DNA oxidation damage, xanthine-oxidase (XO) activity and malondialdehyde levels (MDA) in corneal tissue and prostaglandin E(2) (PGE(2)) in the aqueous humour were reduced by HCAF alone and in combination with p-coumaric acid, showing their potential as a topical treatment against UV-B damage.

  1. Application of 5-Fluorouracil-Polycaprolactone Sustained-Release Film in Ahmed Glaucoma Valve Implantation Inhibits Postoperative Bleb Scarring in Rabbit Eyes

    PubMed Central

    Bi, Xiu-Zeng; Pan, Wei-Hua; Yu, Xin-Ping; Song, Zong-Ming; Ren, Zeng-Jin; Sun, Min; Li, Cong-Hui; Nan, Kai-Hui

    2015-01-01

    This study was designed to investigate whether 5-fluorouracil (5-Fu)-polycaprolactone sustained-release film in Ahmed glaucoma valve implantation inhibits postoperative bleb scarring in rabbit eyes. Eighteen New Zealand white rabbits were randomly divided into three groups (A, B and C; n = 6 per group). Group A received combined 5-Fu-polycaprolactone sustained-release film application and Ahmed glaucoma valve implantation, group B received local infiltration of 5-Fu and Ahmed glaucoma valve implantation, and group C received Ahmed glaucoma valve implantation. Postoperative observations were made of the anterior segment, intraocular pressure, central anterior chamber depth, blebs, drainage tube, and accompanying ciliary body detachment. The pathology of the blebs and surrounding tissues were observed at month 3 postoperatively. We revealed that the 5-Fu-polycaprolactone sustained-release film maintained a release concentration range of 13.7 ± 0.12 to 37.41 ± 0.47 μg/ml over three months in vitro. Postoperatively, diffuse blebs with ridges were found in all eyes in group A, two blebs were observed in group B, and no bleb formation was present in group C. The postoperative central anterior chamber depth in group A was significantly less than that of the other two groups. The postoperative intraocular pressure of group A stabilized at 6.33–8.67 mmHg, whereas that of group C gradually remained at 7.55–10.02 mmHg. The histopathology showed that the fibrous tissue thickness of the blebs in group A was significantly thinner than that of the other groups. We conclude that the 5-Fu-polycaprolactone sustained-release film had a sustained drug release effect, which promoted the inhibition of bleb scarring after Ahmed glaucoma valve implantation. PMID:26579716

  2. Evaluation of the relationship of corneal biomechanical metrics with physical intraocular pressure and central corneal thickness in ex vivo rabbit eye globes.

    PubMed

    Bao, FangJun; Deng, ManLi; Wang, QinMei; Huang, JinHai; Yang, Jing; Whitford, Charles; Geraghty, Brendan; Yu, Ayong; Elsheikh, Ahmed

    2015-08-01

    The relationship of corneal biomechanical metrics provided by the Ocular Response Analyzer (ORA) and Corvis ST (CVS) with physical intraocular pressure (IOPp) and central corneal thickness (CCT) was evaluated. Thirty fresh enucleated eyes of 30 rabbits were used in ex vivo whole globe inflation experiments. IOPp was measured with a pressure transducer and increased from 7.5 to 37.5 mmHg in steps of 7.5 mmHg while biomechanical data was acquired using the ORA and CVS. At least 3 examinations were performed at each pressure level, where CCT and twelve biomechanical metrics were recorded and analyzed as a function of IOPp. The biomechanical metrics included corneal hysteresis (CH) and corneal resistance factor (CRF), obtained by the ORA. They also included the applanation times (A1T, A2T), lengths (A1L, A2L) and velocities (A1V, A2V), in addition to the highest concavity time (HCT), peak distance (PD), radius (HR) and deformation amplitude (DA), obtained by the CVS. The variation of CCT and the twelve biomechanical metrics for the 30 rabbit eyes tested across the 5 pressure stages considered (inter-pressure differences) were statistically significant (P = 0.00). IOPp was highly to moderately correlated with most biomechanical metrics, especially CRF, A1T, A1V, A2V, PD and DA, while the relationships with CH, A2T, A1L and HCT were poor. IOP has important influences on most corneal biomechanical metrics provided by CVS and ORA. Two biomechanical metrics A1V and HR were influenced by CCT after correcting for the effect of IOP in most pressure stages, while the correlation with others were weak. Comparisons of research groups based on ORA and CVS with different IOPs and CCTs may lead to possible misinterpretations if both or one of which are not considered in the analysis.

  3. Application of 5-Fluorouracil-Polycaprolactone Sustained-Release Film in Ahmed Glaucoma Valve Implantation Inhibits Postoperative Bleb Scarring in Rabbit Eyes.

    PubMed

    Bi, Xiu-Zeng; Pan, Wei-Hua; Yu, Xin-Ping; Song, Zong-Ming; Ren, Zeng-Jin; Sun, Min; Li, Cong-Hui; Nan, Kai-Hui

    2015-01-01

    This study was designed to investigate whether 5-fluorouracil (5-Fu)-polycaprolactone sustained-release film in Ahmed glaucoma valve implantation inhibits postoperative bleb scarring in rabbit eyes. Eighteen New Zealand white rabbits were randomly divided into three groups (A, B and C; n = 6 per group). Group A received combined 5-Fu-polycaprolactone sustained-release film application and Ahmed glaucoma valve implantation, group B received local infiltration of 5-Fu and Ahmed glaucoma valve implantation, and group C received Ahmed glaucoma valve implantation. Postoperative observations were made of the anterior segment, intraocular pressure, central anterior chamber depth, blebs, drainage tube, and accompanying ciliary body detachment. The pathology of the blebs and surrounding tissues were observed at month 3 postoperatively. We revealed that the 5-Fu-polycaprolactone sustained-release film maintained a release concentration range of 13.7 ± 0.12 to 37.41 ± 0.47 μg/ml over three months in vitro. Postoperatively, diffuse blebs with ridges were found in all eyes in group A, two blebs were observed in group B, and no bleb formation was present in group C. The postoperative central anterior chamber depth in group A was significantly less than that of the other two groups. The postoperative intraocular pressure of group A stabilized at 6.33-8.67 mmHg, whereas that of group C gradually remained at 7.55-10.02 mmHg. The histopathology showed that the fibrous tissue thickness of the blebs in group A was significantly thinner than that of the other groups. We conclude that the 5-Fu-polycaprolactone sustained-release film had a sustained drug release effect, which promoted the inhibition of bleb scarring after Ahmed glaucoma valve implantation.

  4. Thresholds for Shifting Visually Perceived Eye Level Due to Incremental Pitches

    NASA Technical Reports Server (NTRS)

    Scott, Donald M.; Welch, Robert; Cohen, M. M.; Hill, Cyndi

    2001-01-01

    Visually perceived eye level (VPEL) was judged by subjects as they viewed a luminous grid pattern that was pitched by 2 or 5 deg increments between -20 deg and +20 deg. Subjects were dark adapted for 20 min and indicated--VPEL by directing the beam of a laser pointer to the rear wall of a 1.25 m cubic pitch box that rotated about a horizontal axis midpoint on the rear wall. Data were analyzed by ANOVA and the Tukey HSD procedure. Results showed a 10.0 deg threshold for pitches P(sub i) above the reference pitch P(sub 0), and a -10.3 deg threshold for pitches P(sub i) below-the reference-pitch P(sub 0). Threshold data for pitches P(sub i) < P(sub 0) suggest an asymmetric threshold for VPEL below and above physical eye level.

  5. Penetrating head injury with bilateral eye avulsion due to Himalayan bear bite.

    PubMed

    Roka, Yam B; Roka, Narayani; Shrestha, Manzil; Puri, Puspa R; Adhikari, Hari B

    2012-12-01

    The Himalayan black bear (Ursus thibetanus or Selenarctos thibetanus), although an omnivore, is more carnivorous than its American counterpart. It is also more aggressive towards humans and is a threatened species because of the deforestation in the Himalayas. Furthermore, poverty, encroachment of the forest, extensive deforestation, lack of education and living near the forest are factors that increase the probability of such animal injuries. We report the case of a 35-year-old woman who suffered a severe penetrating head injury with scalp and bilateral eye avulsion, which was managed successfully. © 2012 The Authors. EMA © 2012 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  6. Role of corneal epithelium in riboflavin/ultraviolet-A mediated corneal cross-linking treatment in rabbit eyes.

    PubMed

    Tao, Xiangchen; Yu, Haiqun; Zhang, Yong; Li, Zhiwei; Jhanji, Vishal; Ni, Shouxiang; Wang, Ya; Mu, Guoying

    2013-01-01

    To evaluate the role of corneal epithelium in riboflavin/ultraviolet-A (UVA) mediated corneal collagen cross-linking treatment. Fifty New Zealand rabbits were divided into 5 groups: UVA treatment with or without corneal epithelium, UVA+riboflavin treatment with or without corneal epithelium, and control without any treatment. All rabbits were sacrificed after irradiation and subsequently 4 mm × 10 mm corneal strips were harvested for biomechanical evaluation. UVA irradiation alone did not enhance the maximal stress and Young's modulus of corneal specimens with (3.15 ± 0.56 mpa, 1.00 ± 0.09 mpa) or without (3.53 ± 0.85 mpa, 0.94 ± 0.21 mpa) the corneal epithelium, compared to specimens in the control group (4.30 ± 0.68 mpa, 1.03 ± 0.24 mpa). However, UVA irradiation combined with riboflavin significantly increased the maximal stress and Young's modulus of corneal specimens with (5.27 ± 1.09 mpa, 1.23 ± 0.23 mpa, P < 0.05) or without (7.16 ± 1.88 mpa, 1.42 ± 0.16 mpa, P < 0.05) corneal epithelium when compared to the control group. The maximal stress and Young's modulus of cornea in UVA+riboflavin and "epithelium-off" group were 35.9% and 15.4% higher compared to the UVA+riboflavin and "epithelium-on" group, respectively (P < 0.05). Our study shows that UVA+riboflavin treatment significantly affects the biomechanical properties of the cornea with and without epithelial removal. However, corneas without epithelium seem to benefit more compared to corneas with the epithelium.

  7. Action on diabetic macular oedema: achieving optimal patient management in treating visual impairment due to diabetic eye disease

    PubMed Central

    Gale, R; Scanlon, P H; Evans, M; Ghanchi, F; Yang, Y; Silvestri, G; Freeman, M; Maisey, A; Napier, J

    2017-01-01

    This paper identifies best practice recommendations for managing diabetes and sight-threatening diabetic eye disease. The authors provide an update for ophthalmologists and allied healthcare professionals on key aspects of diabetes management, supported by a review of the pertinent literature, and recommend practice principles for optimal patient management in treating visual impairment due to diabetic eye disease. In people with diabetes, early optimal glycaemic control reduces the long-term risk of both microvascular and macrovascular complications. The authors propose more can and should be done to maximise metabolic control, promote appropriate behavioural modifications and encourage timely treatment intensification when indicated to ameliorate diabetes-related complications. All people with diabetes should be screened for sight-threatening diabetic retinopathy promptly and regularly. It is shown that attitudes towards treatment adherence in diabetic macular oedema appear to mirror patients' views and health behaviours towards the management of their own diabetes. Awareness of diabetic macular oedema remains low among people with diabetes, who need access to education early in their disease about how to manage their diabetes to delay progression and possibly avoid eye-related complications. Ophthalmologists and allied healthcare professionals play a vital role in multidisciplinary diabetes management and establishment of dedicated diabetic macular oedema clinics is proposed. A broader understanding of the role of the diabetes specialist nurse may strengthen the case for comprehensive integrated care in ophthalmic practice. The recommendations are based on round table presentations and discussions held in London, UK, September 2016. PMID:28490797

  8. Action on diabetic macular oedema: achieving optimal patient management in treating visual impairment due to diabetic eye disease.

    PubMed

    Gale, R; Scanlon, P H; Evans, M; Ghanchi, F; Yang, Y; Silvestri, G; Freeman, M; Maisey, A; Napier, J

    2017-05-01

    This paper identifies best practice recommendations for managing diabetes and sight-threatening diabetic eye disease. The authors provide an update for ophthalmologists and allied healthcare professionals on key aspects of diabetes management, supported by a review of the pertinent literature, and recommend practice principles for optimal patient management in treating visual impairment due to diabetic eye disease. In people with diabetes, early optimal glycaemic control reduces the long-term risk of both microvascular and macrovascular complications. The authors propose more can and should be done to maximise metabolic control, promote appropriate behavioural modifications and encourage timely treatment intensification when indicated to ameliorate diabetes-related complications. All people with diabetes should be screened for sight-threatening diabetic retinopathy promptly and regularly. It is shown that attitudes towards treatment adherence in diabetic macular oedema appear to mirror patients' views and health behaviours towards the management of their own diabetes. Awareness of diabetic macular oedema remains low among people with diabetes, who need access to education early in their disease about how to manage their diabetes to delay progression and possibly avoid eye-related complications. Ophthalmologists and allied healthcare professionals play a vital role in multidisciplinary diabetes management and establishment of dedicated diabetic macular oedema clinics is proposed. A broader understanding of the role of the diabetes specialist nurse may strengthen the case for comprehensive integrated care in ophthalmic practice. The recommendations are based on round table presentations and discussions held in London, UK, September 2016.

  9. Neuropathic ocular pain due to dry eye is associated with multiple comorbid chronic pain syndromes

    PubMed Central

    Galor, Anat; Covington, Derek; Levitt, Alexandra E.; McManus, Katherine T.; Seiden, Benjamin; Felix, Elizabeth R.; Kalangara, Jerry; Feuer, William; Patin, Dennis J.; Martin, Eden R.; Sarantopoulos, Konstantinos D.; Levitt, Roy C.

    2015-01-01

    Recent data demonstrate that dry eye (DE) susceptibility and other chronic pain syndromes (CPS) such as chronic widespread pain, irritable bowel syndrome and pelvic pain, may share common heritable factors. Previously, we showed that DE patients describing more severe symptoms tended to report features of neuropathic ocular pain (NOP). We hypothesize that patients with a greater number of CPS would have a different DE phenotype compared to those with fewer CPS. We recruited a cohort of 154 DE patients from the Miami Veterans Affairs Hospital and defined high and low CPS groups by cluster analysis. In addition to worse non-ocular pain complaints and higher PTSD and depression scores (P<0.01), we found that the high CPS group reported more severe neuropathic-type DE symptoms compared to the low CPS group, including worse ocular pain assessed via 3 different pain scales (P<0.05), with similar objective corneal DE signs. This is the first study to demonstrate DE patients who manifest a greater number of comorbid CPS report more severe DE symptoms and features of NOP. These findings provide further evidence that NOP may represent a central pain disorder, and that shared mechanistic factors may underlie vulnerability to some forms of DE and other comorbid CPS. PMID:26606863

  10. Pro-Secretory Activity and Pharmacology in Rabbits of an Aminophenyl-1,3,5-Triazine CFTR Activator for Dry Eye Disorders

    PubMed Central

    Felix, Christian M.; Lee, Sujin; Levin, Marc H.; Verkman, Alan S.

    2017-01-01

    Purpose Pharmacological activation of ocular surface cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels is a potential pro-secretory approach to treat dry eye disorders. We previously reported the discovery of aminophenyl-1,3,5-triazines, one of which, N-methyl-N-phenyl-6-(2,2,3,3-tetrafluoropropoxy)-1,3,5-triazine-2,4-diamine (herein called CFTRact-K267), fully activated human wildtype CFTR with EC50 ∼ 30 nM and increased tear volume for 8 hours in mice. Here, functional and pharmacological studies of CFTRact-K267 were done in adult New Zealand white rabbits. Methods CFTR chloride conductance was measured in vivo by ocular surface potential differences and in ex vivo conjunctiva by short-circuit current. Tear volume was measured by the Schirmer tear test II and CFTRact-K267 pharmacokinetics and tissue distribution by liquid chromatography/mass spectrometry. Toxicity profile was studied for 28 days with twice-daily topical administration. Results Electrophysiological measurements in vivo and in ex vivo conjunctiva demonstrated CFTR activation by CFTRact-K267. A single topical dose of 3 nmol CFTRact-K267 increased tear production by >5 mm for 9 hours by the Schirmer tear test, with predicted therapeutic concentrations maintained in tear fluid. No tachyphylaxis was seen following 28-day twice-daily administration, and changes were not observed in corneal surface integrity or thickness, intraocular pressure, or ocular histology. At day 28, CFTRact-K267 was concentrated in the cornea and conjunctiva and was not detectable in blood or peripheral organs. Conclusions These studies support the development of CFTRact-K267 as a pro-secretory therapy for dry eye disorders. PMID:28873176

  11. A three-tier QSAR modeling strategy for estimating eye irritation potential of diverse chemicals in rabbit for regulatory purposes.

    PubMed

    Basant, Nikita; Gupta, Shikha; Singh, Kunwar P

    2016-06-01

    Experimental determination of the eye irritation potential (EIP) of chemicals is not only tedious, time and resource intensive, it involves cruelty to test animals. In this study, we have established a three-tier QSAR modeling strategy for estimating the EIP of chemicals for the use of pharmaceutical industry and regulatory agencies. Accordingly, a qualitative (binary classification: irritating, non-irritating), semi-quantitative (four-category classification), and quantitative (regression) QSAR models employing the SDT, DTF, and DTB methods were developed for predicting the EIP of chemicals in accordance with the OECD guidelines. Structural features of chemicals responsible for eye irritation were extracted and used in QSAR analysis. The external predictive power of the developed QSAR models were evaluated through the internal and external validation procedures recommended in QSAR literature. In test data, the two and four category classification QSAR models (DTF, DTB) rendered accuracy of >93%, while the regression QSAR models (DTF, DTB) yielded correlation (R(2)) of >0.92 between the measured and predicted EIPs. Values of various statistical validation coefficients derived for the test data were above their respective threshold limits (except rm(2) in DTF), thus put a high confidence in this analysis. The applicability domain of the constructed QSAR models were defined using the descriptors range and leverage approaches. The QSAR models in this study performed better than any of the previous studies. The results suggest that the developed QSAR models can reliably predict the EIP of diverse chemicals and can be useful tools for screening of candidate molecules in the drug development process. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Ketorolac eye drops reduce inflammation and delay re-epithelization in response to corneal alkali burn in rabbits, without affecting iNOS or MMP-9.

    PubMed

    Lima, Tiago Barbalho; Ribeiro, Alexandre Pinto; Conceição, Luciano Fernandes da; Bandarra, Marcio; Manrique, Wilson Gomez; Laus, José Luiz

    2015-01-01

    To assess the effects of 0.5% ketorolac tromethamine without preservatives on the expression of iNOS and MMP-9 in alkali burn ulcers. Twelve eyes of 120-day-old male rabbits were treated (TG) every 6 h with 0.5% ketorolac tromethamine and 12 other eyes were treated with saline solution (CG), immediately after the occurrence of ulcers by 1 M sodium hydroxide (NaOH). Re-epithelialization was monitored using fluorescein every 6 h. After 24 h, six corneas (n=6) of each group were collected (M1). The others (n=6) were collected after reepithelialization (M2). At both moments, the inflammatory infiltrate and the conditions of the newly formed epithelium were histologically analyzed. iNOS and MMP-9 were evaluated by immunohistochemistry. Mean epithelialization time in TG was 55 ± 0.84 h. In CG, it was 44 ± 1.06 h (p=0.001). At M1, corneas of TG had lower inflammatory exudation compared with (p <0.001). At M2, TG revealed discrete inflammatory exudation (p>0.05) and lower numbers of epithelial layers compared with CG. The mean iNOS in stromal cells did not differ in TG over both moments compared with CG (p>0.05) At M2, the central corneal region expressed more iNOS in both groups compared with the peripheral region. No significant differences were observed in iNOS scores of epithelial immunostaining between the groups and across M1 and M2 (p=0.69). Epithelial immunostaining scores for MMP-9 did not differ in TG compared with CG (p=0.69). The average immunostaining score of MMP-9 in stromal cells showed no differences between groups or moments. There was no correlation between immunostaining of iNOS and MMP-9 or between the amount of inflammatory cells and immunostaining of iNOS. Use of 0.5% keratolac tromethamine reduced inflammation and delayed reepithelialization in a cornea alkali burn model without impacting the expression of iNOS or MMP-9.

  13. Wide variations in herpes simplex virus type 1 inoculum dose and latency-associated transcript expression phenotype do not alter the establishment of latency in the rabbit eye model.

    PubMed

    O'Neil, J E; Loutsch, J M; Aguilar, J S; Hill, J M; Wagner, E K; Bloom, D C

    2004-05-01

    The latency-associated transcript (LAT) is required for efficient reactivation of herpes simplex virus type 1 from latent infection in the rabbit eye model, but LAT's mechanism of action is unknown. In addition to reactivation, the LAT region seems to correspond to multiple functions, with some LAT deletion mutants exhibiting increased virulence, increased neuronal death, and restricted establishment of latency. While a LAT promoter deletion mutant (17DeltaPst) seems to be primarily restricted in reactivation in the rabbit, subtle effects on virulence or the establishment of latency cannot be precluded at the normal high levels of virus inoculum used in the rabbit model. Since such additional LAT phenotypes may be more evident with lower doses of virus, we evaluated the influence of initial viral inoculum and LAT expression on the progression of acute infection and the establishment of latency. We have assayed both virus recovery rates and viral genome loads in rabbit corneas and trigeminal ganglia. Our results show that (i) in the corneas and trigeminal ganglia, the maximum amount of virus present during acute infection is independent of the LAT genotype and inoculum dose, although greater viral yields are obtained earlier with higher inoculum doses, and (ii) the range in numbers of latent genomes detected in the ganglia is independent of the inoculum dose and the LAT genotype and therefore no difference in establishment of latency is observed.

  14. Exogenous Streptococcus pneumoniae Endophthalmitis in Diabetic Rabbits

    PubMed Central

    Benton, Angela H.; Fulton, Linda K.; Marquart, Mary E.

    2017-01-01

    Diabetics are at increased risk for eye infections including bacterial endophthalmitis. It is unclear whether the severity of endophthalmitis is greater in these patients due to confounding factors such as pre-existing ocular diseases in some but not others. Therefore, we tested the hypothesis that disease severity and/or bacterial loads would be significantly higher in a Type I diabetic rabbit model of Streptococcus pneumoniae endophthalmitis. Rabbits were treated with alloxan to destroy pancreatic islet cells, or mock-treated with vehicle, and maintained for 10 days before intravitreal infection with S. pneumoniae E353. Clinical scoring of the eyes was performed 24 and 48 hours after infection, followed by euthanasia and vitreous harvest to quantitate bacterial loads. There were no significant differences in clinical scores (P ≥ 0.440) or bacterial loads (P = 0.736), however, 4/12 (33%) of the diabetic rabbits became bacteremic. This finding not only indicates a breakdown in the blood-ocular barrier, but also prompts further investigation into the exploitation of the diabetic eye by the streptococci. PMID:28387365

  15. The first recorded outbreak of cryptosporidiosis due to Cryptosporidium cuniculus (formerly rabbit genotype), following a water quality incident.

    PubMed

    Puleston, Richard L; Mallaghan, Cathy M; Modha, Deborah E; Hunter, Paul R; Nguyen-Van-Tam, Jonathan S; Regan, Christopher M; Nichols, Gordon L; Chalmers, Rachel M

    2014-03-01

    We report the first identified outbreak of cryptosporidiosis with Cryptosporidium cuniculus following a water quality incident in Northamptonshire, UK. A standardised, enhanced Cryptosporidium exposure questionnaire was administered to all cases of cryptosporidiosis after the incident. Stool samples, water testing, microscopy slides and rabbit gut contents positive for Cryptosporidium were typed at the Cryptosporidium Reference Unit, Singleton Hospital, Swansea. Twenty-three people were microbiologically linked to the incident although other evidence suggests an excess of 422 cases of cryptosporidiosis above baseline. Most were adult females; unusually for cryptosporidiosis there were no affected children identified under the age of 5 years. Water consumption was possibly higher than in national drinking water consumption patterns. Diarrhoea duration was negatively correlated to distance from the water treatment works where the contamination occurred. Oocyst counts were highest in water storage facilities. This outbreak is the first caused by C. cuniculus infection to have been noted and it has conclusively demonstrated that this species can be a human pathogen. Although symptomatically similar to cryptosporidiosis from C. parvum or C. hominis, this outbreak has revealed some differences, in particular no children under 5 were identified and females were over-represented. These dissimilarities are unexplained although we postulate possible explanations.

  16. Light stimulation of iris tyrosinase in vivo. [Rabbits

    SciTech Connect

    Dryja, T.P.; Kimball, G.P.; Albert, D.M.

    1980-05-01

    This paper presents evidence that light stimulates tyrosinase activity in iris melanocytes in rabbits. Levels of iris tyrosinase were found to be greater in eyes of rabbits exposed to light for 6 weeks than in eyes of rabbits maintained in darkness. Despite increasing tyrosinase levels, exposure to light produced no clinically observable change in iris color.

  17. Determination of ofloxacin in tear by HPLC-ESI-MS/MS method: comparison of ophthalmic drug release between a new mucoadhesive chitosan films and a conventional eye drop formulation in rabbit model.

    PubMed

    Byrro, Ricardo Martins Duarte; de Oliveira Fulgêncio, Gustavo; da Silva Cunha, Armando; César, Isabela Costa; Chellini, Paula Rocha; Pianetti, Gerson Antônio

    2012-11-01

    Ofloxacin, second-generation fluoroquinolone derivative, is one of the most commonly used to treat and prevent superficial ocular infection in animals and human beings. However, poor bioavailability, rapid elimination, and non compliance by patients are several problems associated with ocular route. Ophthalmic controlled drug delivery offers the potential to enhance the efficacy of treatment for pathological conditions, while reducing the side effects and the toxicity associated with frequent applications. Specific analytical methods to determine drugs in eye are needed to analyze and compare the new controlled release ocular devices with those conventional eye drops. The topical eye administration of ophthalmic drugs induces lachrymation, and the tear promotes a drug wash out. Quantify drugs in tear is a good tool to study their kinetic comportment in the eye. A liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) method for quantitation of ofloxacin in rabbits' tears was developed and validated. The tear was collected with tear strips, extracted by a liquid extraction procedure and then separated on an ACE C(18) column with a mobile phase composed of 0.15% aqueous formic acid and methanol (60:40, v/v). Calibration curve was constructed over the range of 10-5000 ng/mL for ofloxacin. The mean R.S.D. values for the intra-run and inter-run precision were 5.15% and 4.35%, respectively. The mean accuracy value was 100.16%. The validated method was successfully applied to determine the ofloxacin concentration in tears of rabbits treated with a mucoadhesive chitosan films and a conventional eye drop formulation. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Retinal endoilluminator toxicity of xenon and light-emitting diode (LED) light source: rabbit model.

    PubMed

    Aydin, Bahri; Dinç, Erdem; Yilmaz, S Necat; Altiparmak, U Emrah; Yülek, Fatma; Ertekin, Sevda; Yilmaz, Mustafa; Yakın, Mehmet

    2014-09-01

    This study evaluates retinal toxicity due to endoillumination with the light-emitting diode (LED) light source in comparison to endoillumination with xenon light source. Twenty-five eyes of 14 New Zealand pigmented rabbits were used in the study. The LED light (Omesis Medical Systems, Turkey) group was composed of 7 right eyes, while the other 7 right eyes constituted the xenon group (420 nm filter, 357mW/cm(2)) (Bright Star; DORC, Zuidland, Netherlands). Eleven untreated left eyes composed the control group. Twenty gauge pars plana incision 1.5 mm behind the limbus was performed in the right eyes. Twenty gauge bullet type fiberoptic endoilluminator was inserted into the eye from the incision without any pars plana vitrectomy. Fiberoptic endoilluminator was placed in such a way that it was directed toward visual streak of the rabbit retina with a 5 mm distance to retinal surface. Endoillumination was then applied for 20 min with a maximum light intensity for LED and xenon light. In left control eyes, no surgical procedure and no endoillumination were performed. One week after the endoillumination procedure, both eyes of the rabbits were enucleated following electroretinography. Sections stained with hematoxylin and eosin to evaluate morphologic changes. Retina tissues were assessed by active caspase-3 staining. There was no difference in the shape of the waveforms recorded in the eyes endoilluminated with LED light and xenon light sources compared to control eyes both before and after endoillumination application (p > 0.05). Microscopic evaluation of the retinas with hematoxylin and eosin staining demonstrated that all study groups have normal histologic properties similar to control group. No apoptosis positive cells were found within all sections in all groups. When the LED light source is used with maximum power and limited duration for endoillumination in rabbit eyes it does not produce phototoxic effects that may be detectable by electrophysiology

  19. Oculoscopy in Rabbits and Rodents.

    PubMed

    Jekl, Vladimir; Hauptman, Karel; Knotek, Zdenek

    2015-09-01

    Ophthalmic diseases are common in rabbits and rodents. Fast and definitive diagnosis is imperative for successful treatment of ocular diseases. Ophthalmic examination in rabbits and rodents can be challenging. Oculoscopy offers great magnification for the examination of the ocular structures in such animals, including the evaluation of cornea, anterior eye chamber, limbus, iris, lens, and retina. To date, oculoscopy has been described only sporadically and/or under experimental conditions. This article describes the oculoscopy technique, normal and abnormal ocular findings, and the most common eye disorders diagnosed with the aid of endoscopy in rabbits and rodents.

  20. Effects on shortening velocity of rabbit skeletal muscle due to variations in the level of thin-filament activation.

    PubMed Central

    Moss, R L

    1986-01-01

    The effect of Ca2+ upon maximum shortening velocity (Vmax) has been investigated in skinned single fibres from rabbit psoas muscles. Vmax was obtained at 15 degrees C by measuring the amounts of time (delta t) required to take up various amounts of slack (delta l) imposed at one end of the fibre. During maximal activation with Ca2+, plots of delta l vs. delta t were well fitted by a single straight line. Calculation of Vmax from the slopes of the fitted lines yielded a Vmax of 4.44 +/- 0.15 (S.E. of mean) muscle lengths per second (m.l./s). However, at lower levels of Ca2+ activation, plots of delta l vs. delta t were biphasic, containing an initial phase of steady high-velocity shortening and a subsequent phase of steady low-velocity shortening. The transition between these two phases occurred following active shortening equivalent to 60-80 nm/half-sarcomere. Vmax during the high-velocity phase was relatively insensitive to Ca2+ concentration between pCas (i.e. -log [Ca2+]) of 4.5 and 6.0; however, Vmax fell to 3.58 +/- 0.40 m.l./s at pCa 6.1 and further to 1.02 +/- 0.30 m.l./s at pCa 6.2. Vmax during the low-velocity phase decreased as Ca2+ was lowered within the entire range of pCas studied to a minimum value of 0.35 +/- 0.09 m.l./s at pCa 6.2. The degree of thin-filament activation at a particular pCa was varied by partial extraction of troponin-C, which resulted in a permanent though reversible inactivation of parts of the thin filaments. Partial extraction of troponin-C altered the plots of delta l vs. delta t obtained at pCa 4.5 to a biphasic form. In addition, Vmax during the high- and low-velocity phases of shortening was reduced at each pCa greater than 4.5. Vmax values obtained in control fibres at low Ca2+ concentrations and extracted fibres were in good agreement when generated isometric tensions were equivalent. This was the case for both the high- and low-velocity phases of shortening. Fibres were also activated in the absence of Ca2+ by partial

  1. Pet rabbits.

    PubMed

    Hillyer, E V

    1994-01-01

    Pet rabbits are becoming more common, and rabbit owners are demanding quality veterinary care. This article provides a broad overview of pet rabbit medicine, which is a relatively new field compared to laboratory and farm rabbit medicine. The most common differential diagnoses for presenting complaints are summarized in table form. Disease conditions are reviewed individually in the text. Sources of further information on veterinary care of rabbits are listed throughout the text, in an appendix, and in the references.

  2. Estimating Frequency and Size of Effects Due to Experimental Manipulations in Eye Movement Research. Technical Report No. 338.

    ERIC Educational Resources Information Center

    McConkie, George W.; And Others

    A study of eye movements was conducted to determine whether the visual regions are perceived in their entirety on each fixation or whether the actual region perceived varies from fixation to fixation. The resulting data were used in a frequency of effects analysis. The frequency of effects problem arises once it has been established that an…

  3. Red-shift of spectral sensitivity due to screening pigment migration in the eyes of a moth, Adoxophyes orana.

    PubMed

    Satoh, Aya; Stewart, Finlay J; Koshitaka, Hisaharu; Akashi, Hiroshi D; Pirih, Primož; Sato, Yasushi; Arikawa, Kentaro

    2017-01-01

    We have found that the spectral sensitivity of the compound eye in the summer fruit tortrix moth (Adoxophyes orana) differs in laboratory strains originating from different regions of Japan. We have investigated the mechanisms underlying this anomalous spectral sensitivity. We applied electrophysiology, light and electron microscopy, opsin gene cloning, mathematical modeling, and behavioral analysis. The ERG-determined spectral sensitivity of dark-adapted individuals of all strains peaks around 520 nm. When light-adapted, the spectral sensitivity of the Nagano strain narrows and its peak shifts to 580 nm, while that in other strains remains unchanged. All tested strains appear to be identical in terms of the basic structure of the eye, the pigment migration in response to light- and dark-adaptation, and the molecular structure of long-wavelength absorbing visual pigments. However, the color of the perirhabdomal pigment clearly differs; it is orange in the Nagano strain and purple in the others. The action spectrum of phototaxis appears to be shifted towards longer wavelengths in the Nagano individuals. The spectral sensitivities of light-adapted eyes can be modeled under the assumption that this screening pigment plays a crucial role in determining the spectral sensitivity. The action spectrum of phototaxis indicates that the change in the eye spectral sensitivity is behaviorally relevant.

  4. Computing the stresses and deformations of the human eye components due to a high explosive detonation using fluid-structure interaction model.

    PubMed

    Karimi, Alireza; Razaghi, Reza; Navidbakhsh, Mahdi; Sera, Toshihiro; Kudo, Susumu

    2016-05-01

    In spite the fact that a very small human body surface area is comprised by the eye, its wounds due to detonation have recently been dramatically amplified. Although many efforts have been devoted to measure injury of the globe, there is still a lack of knowledge on the injury mechanism due to Primary Blast Wave (PBW). The goal of this study was to determine the stresses and deformations of the human eye components, including the cornea, aqueous, iris, ciliary body, lens, vitreous, retina, sclera, optic nerve, and muscles, attributed to PBW induced by trinitrotoluene (TNT) explosion via a Lagrangian-Eulerian computational coupling model. Magnetic Resonance Imaging (MRI) was employed to establish a Finite Element (FE) model of the human eye according to a normal human eye. The solid components of the eye were modelled as Lagrangian mesh, while an explosive TNT, air domain, and aqueous were modelled using Arbitrary Lagrangian-Eulerian (ALE) mesh. Nonlinear dynamic FE simulations were accomplished using the explicit FE code, namely LS-DYNA. In order to simulate the blast wave generation, propagation, and interaction with the eye, the ALE formulation with Jones-Wilkins-Lee (JWL) equation defining the explosive material were employed. The results revealed a peak stress of 135.70kPa brought about by detonation upsurge on the cornea at the distance of 25cm. The highest von Mises stresses were observed on the sclera (267.3kPa), whereas the lowest one was seen on the vitreous body (0.002kPa). The results also showed a relatively high resultant displacement for the macula as well as a high variation for the radius of curvature for the cornea and lens, which can result in both macular holes, optic nerve damage and, consequently, vision loss. These results may have implications not only for understanding the value of stresses and strains in the human eye components but also giving an outlook about the process of PBW triggers damage to the eye. Copyright © 2016 Elsevier Ltd

  5. High susceptibility of atherosclerotic coronary arteries to the onset of vasospasm and angina pectoris-like symptoms due to coronary spasm in WHHLMI rabbits

    PubMed Central

    Koike, Tomonari; Tamura, Shiori; Yu, Ying; Kuniyoshi, Nobue; Shiomi, Masashi

    2016-01-01

    We examined the relationship between atherosclerosis and the provocation of coronary spasm as well as the influence of coronary spasm on the onset of acute ischemic myocardial disease. Coronary spasm was provoked in anesthetized normal Japanese white (JW) rabbits and myocardial infarction-prone Watanabe heritable hyperlipidemic (WHHLMI) rabbits, an animal model for coronary atherosclerosis and myocardial infarction, by injecting ergonovine during the infusion of norepinephrine through a marginal ear vein. A decrease in contrast flow in the left circumflex artery was observed on coronary angiograms. Ischemic changes were observed on the electrocardiograms of 29% (2/7) of JW and 79% (27/34, P=0.007) of WHHLMI rabbits. The frequency of coronary spasm was significantly high in rabbits with severe coronary plaques showing diffuse lesions. Left ventricle motility in vasospasm-positive rabbits, which was evaluated with echocardiograms, was decreased by 29% following the ergonovine injection (P<0.001), and every serum ischemic marker markedly increased 4 h after the provocation of vasospasm. These results demonstrate that atherosclerotic coronary arteries are positively related to the provocation of vasospasm, and vasospasm in severe atherosclerotic coronary segments evokes angina pectoris-like findings and/or non-fatal myocardial infarction. WHHLMI rabbits may be a novel animal model for angina pectoris and acute ischemic heart disease. PMID:27301847

  6. Rabbit medicine.

    PubMed

    Jordan, Dinah G

    2007-01-01

    When filling prescriptions for a rabbit, it is important to know whether the rabbit is a pet or is being raised as a source of food for human consumption. Several drugs widely used for pet rabbits are prohibited from exralabel use in animals raised for food production. The list of banned drugs should always be perused prior to filling a prescription for a rabbit being raised for food production. Since no veterinary-approved products exist for rabbits and most medications must be compounded, pharmacists are likely to encounter prescriptions for rabbits in their practice. A basic understanding of rabbit anatomy, physiolgy and common diseases will assist pharmacists in distinguishing between safe and dangerous drugs for administration to rabbits.

  7. Expression of mutant CHMP2B, an ESCRT-III component involved in frontotemporal dementia, causes eye deformities due to Notch misregulation in Drosophila

    PubMed Central

    Cheruiyot, Abigael; Lee, Jin-A; Gao, Fen-Biao; Ahmad, S. Tariq

    2014-01-01

    Endosomal sorting complexes required for transport (ESCRTs) mediate sorting of ubiquitinated membrane proteins into multivesicular bodies en route to lysosomes for degradation. A mutation in CHMP2B (CHMP2BIntron5, an ESCRT-III component) that is associated with a hereditary form of frontotemporal dementia (FTD3) disrupts the endosomal-lysosomal pathway and causes accumulation of autophagosomes and multilamellar structures. We previously demonstrated that expression of CHMP2BIntron5 in the Drosophila eye using GMR-Gal4 causes misregulation of the Toll receptor pathway. Here, we show that ectopic expression of CHMP2BIntron5 using eyeless-Gal4 (ey>CHMP2BIntron5), a driver with different spatiotemporal expression attributes than GMR-Gal4 in the Drosophila eye, causes eye deformities when compared to expression of wild-type CHMP2B (CHMP2BWT) and the Drosophila homologue of CHMP2B (CG4618). In addition, ey>CHMP2BIntron5 flies showed defects in photoreceptor cell patterning and phototactic behavior. Furthermore, ey>CHMP2BIntron5 flies showed accumulation of Notch in enlarged endosomes and up-regulation of Notch activity. Partial loss of Notch activity in ey>CHMP2BIntron5 flies significantly rescued eye deformities, photoreceptor patterning defect, and phototactic behavior defect, indicating that these defects are primarily due to Notch misregulation. These results demonstrate that CHMP2BIntron5 preferentially affects different receptor signaling pathways in a cellular and developmental context-dependent manner.—Cheruiyot, A., Lee, J-A., Gao, F-B., Ahmad, S. T. Expression of mutant CHMP2B, an ESCRT-III component involved in frontotemporal dementia, causes eye deformities due to Notch misregulation in Drosophila. PMID:24158394

  8. Disposable rabbit

    DOEpatents

    Lewis, Leroy C.; Trammell, David R.

    1986-01-01

    A disposable rabbit for transferring radioactive samples in a pneumatic transfer system comprises aerated plastic shaped in such a manner as to hold a radioactive sample and aerated such that dissolution of the rabbit in a solvent followed by evaporation of the solid yields solid waste material having a volume significantly smaller than the original volume of the rabbit.

  9. Disposal rabbit

    DOEpatents

    Lewis, L.C.; Trammell, D.R.

    1983-10-12

    A disposable rabbit for transferring radioactive samples in a pneumatic transfer system comprises aerated plastic shaped in such a manner as to hold a radioactive sample and aerated such that dissolution of the rabbit in a solvent followed by evaporation of the solid yields solid waste material having a volume significantly smaller than the original volume of the rabbit.

  10. Short-term safety of dexamethasone implant for treatment of macular edema due to retinal vein occlusion, in eyes with glaucoma or treated ocular hypertension.

    PubMed

    Theodoropoulou, Sofia; Ellabban, Abdallah A; Johnston, Robert L; Cilliers, Helena; Mohamed, Quresh; Sallam, Ahmed B

    2017-04-01

    To report the short-term safety of dexamethasone implants to treat macular edema due to retinal vein occlusion (RVO), in eyes with treated glaucoma or ocular hypertension at baseline using an as-needed re-treatment regimen. Retrospective clinical database study from two centers using the same electronic medical record system. Extracted data included: intraocular pressure (IOP), visual acuity (VA), central 1 mm retinal thickness (CRT) by optical coherence tomography, phakic status, number of injections, glaucoma treatment, and peri-operative complications. Thirty-three eyes of 33 patients on IOP-lowering treatment for glaucoma or ocular hypertension (OHT) at baseline and mean IOP of 16 mmHg at baseline received one to four (mean, 1.8; median, 1) dexamethasone implants over 18 months for RVO-related macular edema. Fourteen eyes (42 %) had IOP of ≥21 mmHg, and three eyes (9 %) had IOP of ≥35 mmHg at one or more visits during the study period. Nine of 14 eyes (64 %) with raised IOP required additional topical treatment only for a mean (SE) period of 8.5 months (3.2), while the remaining five eyes (36 %) required long-term additional IOP-lowering treatment for a mean (SE) of 16 months (1.44). Surgery for IOP lowering was not required in any eye. Mean VA (SE) improved from 44 (3) ETDRS letters at baseline to 47 letters (5) at 2 months (p = 0.049), 48 (8) letters at 6 months and 46 (4) letters at 12 months. Mean CRT (SE) improved from 530 (25) μm at baseline to 323 (27) μm at 2 months (p < 0.001), 498 (76) μm at 6 months, and 359 (25) μm at 12 months (p < 0.001). The short-term IOP rise after intravitreal dexamethasone implant in eyes with glaucoma or ocular hypertension at baseline was acceptable and consistent with previous reports in patients without preexisting glaucoma. Treated OHT or glaucoma may not be a strict contraindication against the use of dexamethasone implant, but close monitoring of IOP is required.

  11. Prolonged Ocular Retention of Mucoadhesive Nanoparticle Eye Drop Formulation Enables Treatment of Eye Diseases Using Significantly Reduced Dosage.

    PubMed

    Liu, Shengyan; Dozois, Matthew D; Chang, Chu Ning; Ahmad, Aaminah; Ng, Deborah L T; Hileeto, Denise; Liang, Huiyuan; Reyad, Matthew-Mina; Boyd, Shelley; Jones, Lyndon W; Gu, Frank X

    2016-09-06

    Eye diseases, such as dry eye syndrome, are commonly treated with eye drop formulations. However, eye drop formulations require frequent dosing with high drug concentrations due to poor ocular surface retention, which leads to poor patient compliance and high risks of side effects. We developed a mucoadhesive nanoparticle eye drop delivery platform to prolong the ocular retention of topical drugs, thus enabling treatment of eye diseases using reduced dosage. Using fluorescent imaging on rabbit eyes, we showed ocular retention of the fluorescent dye delivered through these nanoparticles beyond 24 h while free dyes were mostly cleared from the ocular surface within 3 h after administration. Utilizing the prolonged retention of the nanoparticles, we demonstrated effective treatment of experimentally induced dry eye in mice by delivering cyclosporin A (CsA) bound to this delivery system. The once a week dosing of 0.005 to 0.01% CsA in NP eye drop formulation demonstrated both the elimination of the inflammation signs and the recovery of ocular surface goblet cells after a month. Thrice daily administration of RESTASIS on mice only showed elimination without recovering the ocular surface goblet cells. The mucoadhesive nanoparticle eye drop platform demonstrated prolonged ocular surface retention and effective treatment of dry eye conditions with up to 50- to 100-fold reduction in overall dosage of CsA compared to RESTASIS, which may significantly reduce side effects and, by extending the interdosing interval, improve patient compliance.

  12. Homemade lyophilized cross linking amniotic sustained-release drug membrane with anti-scarring role after filtering surgery in rabbit eyes

    PubMed Central

    Li, Wan; Chen, Wen-Jian; Liu, Wei; Liang, Liang; Zhang, Ming-Chang

    2012-01-01

    AIM To investigate the antifibrotic effect of the freeze-dried bilayered fibrin-binding amniotic membrane as a drug delivery system on glaucoma surgery in rabbit model. The aim of this study was to prepare a novel local delivery system for the sustained and controllable release of 5-Fu. METHODS Twenty-four Japanese white rabbits were randomized into three groups: the experimental group (ocular trabeculectomy in combination with 5-Fu loaded freeze-dried bilayered fibrin-binding amniotic membrane transplantation), the control group (ocular trabeculectomy in combination with 5-Fu) and the blank group (single trabeculectomy). HE staining, massion staining and immunohistochemistry for α-SMA were performed on days 7, 14, 21 and 30 following surgery. The concentration of 5-Fu in rabbit aqueous humor was examined by high performance liquid chromatography (HPLC) 3 days after the surgery. RESULTS Statistical differences were noted in intraocular pressure among groups on day 7, 14, 21 and 30 following surgery. Histology further demonstrated that trabeculectomy in combination with freeze-dried bilayered fibrin-binding amniotic membrane yielded well wound healing and no scar formation and was beneficial for long term effect. CONCLUSION HPLC showed a good slow-release effect with freeze-dried bilayered fibrin-binding amniotic membrane. PMID:23166864

  13. Expression of mutant CHMP2B, an ESCRT-III component involved in frontotemporal dementia, causes eye deformities due to Notch misregulation in Drosophila.

    PubMed

    Cheruiyot, Abigael; Lee, Jin-A; Gao, Fen-Biao; Ahmad, S Tariq

    2014-02-01

    Endosomal sorting complexes required for transport (ESCRTs) mediate sorting of ubiquitinated membrane proteins into multivesicular bodies en route to lysosomes for degradation. A mutation in CHMP2B (CHMP2B(Intron5), an ESCRT-III component) that is associated with a hereditary form of frontotemporal dementia (FTD3) disrupts the endosomal-lysosomal pathway and causes accumulation of autophagosomes and multilamellar structures. We previously demonstrated that expression of CHMP2B(Intron5) in the Drosophila eye using GMR-Gal4 causes misregulation of the Toll receptor pathway. Here, we show that ectopic expression of CHMP2B(Intron5) using eyeless-Gal4 (ey>CHMP2B(Intron5)), a driver with different spatiotemporal expression attributes than GMR-Gal4 in the Drosophila eye, causes eye deformities when compared to expression of wild-type CHMP2B (CHMP2B(WT)) and the Drosophila homologue of CHMP2B (CG4618). In addition, ey>CHMP2B(Intron5) flies showed defects in photoreceptor cell patterning and phototactic behavior. Furthermore, ey>CHMP2B(Intron5) flies showed accumulation of Notch in enlarged endosomes and up-regulation of Notch activity. Partial loss of Notch activity in ey>CHMP2B(Intron5) flies significantly rescued eye deformities, photoreceptor patterning defect, and phototactic behavior defect, indicating that these defects are primarily due to Notch misregulation. These results demonstrate that CHMP2B(Intron5) preferentially affects different receptor signaling pathways in a cellular and developmental context-dependent manner.

  14. Prospective evaluation of intense pulsed light and meibomian gland expression efficacy on relieving signs and symptoms of dry eye disease due to meibomian gland dysfunction.

    PubMed

    Dell, Steven J; Gaster, Ronald N; Barbarino, Sheila C; Cunningham, Derek N

    2017-01-01

    The aim of this study was to estimate the efficacy of intense pulsed light (IPL), followed by meibomian gland expression (MGX), for reducing the number and severity of signs and symptoms of dry eye disease (DED) secondary to meibomian gland dysfunction (MGD). In a prospective study conducted in two sites, 40 subjects (80 eyes) with moderate to severe MGD were enrolled. Major inclusion criteria consisted of at least two of the following measures being compatible with DED in both eyes: tear breakup time (TBUT), meibomian gland score (MGS), corneal fluorescein staining (CFS), Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire, and tear film osmolarity (TFO). Enrolled patients underwent four treatment sessions, 3 weeks apart. Each treatment included the administration of 10-15 pulses of IPL on the cheeks and nose, followed by MGX of the upper and lower eyelids. TBUT, MGS, CFS, SPEED, TFO, and lipid layer thickness (LLT) were measured at baseline (BL) and at 9, 12, and 15 weeks after BL. Due to different staining methods used for TBUT measurements, TBUT and CFS were analyzed separately for each site. From BL to the final follow-up, the number of signs compatible with DED decreased from 3.3±0.1 to 1.4±0.1. TBUT improved by +93% (n=38; P<0.0001) and +425% (n=42; P<0.0001) for sites 1 and 2, respectively. SPEED, MGS, and CFS improved by -55% (n=80; P<0.0001), -36% (n=80; P<0.0001), and -58% (n=38; P<0.0001), respectively. In 20 eyes with abnormally elevated TFO at BL, TFO improved by -7% (n=20; P<0.005). LLT did not change (n=38; P=0.88). In subjects with moderate to severe MGD, IPL combined with MGX reduced the number and severity of symptoms and signs of DED. Except for LLT, all examined outcome measures significantly improved after 15 weeks. These results support the efficacy of IPL + MGX in relieving both signs and symptoms of DED secondary to MGD.

  15. Prospective evaluation of intense pulsed light and meibomian gland expression efficacy on relieving signs and symptoms of dry eye disease due to meibomian gland dysfunction

    PubMed Central

    Dell, Steven J; Gaster, Ronald N; Barbarino, Sheila C; Cunningham, Derek N

    2017-01-01

    Purpose The aim of this study was to estimate the efficacy of intense pulsed light (IPL), followed by meibomian gland expression (MGX), for reducing the number and severity of signs and symptoms of dry eye disease (DED) secondary to meibomian gland dysfunction (MGD). Patients and methods In a prospective study conducted in two sites, 40 subjects (80 eyes) with moderate to severe MGD were enrolled. Major inclusion criteria consisted of at least two of the following measures being compatible with DED in both eyes: tear breakup time (TBUT), meibomian gland score (MGS), corneal fluorescein staining (CFS), Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire, and tear film osmolarity (TFO). Enrolled patients underwent four treatment sessions, 3 weeks apart. Each treatment included the administration of 10–15 pulses of IPL on the cheeks and nose, followed by MGX of the upper and lower eyelids. TBUT, MGS, CFS, SPEED, TFO, and lipid layer thickness (LLT) were measured at baseline (BL) and at 9, 12, and 15 weeks after BL. Results Due to different staining methods used for TBUT measurements, TBUT and CFS were analyzed separately for each site. From BL to the final follow-up, the number of signs compatible with DED decreased from 3.3±0.1 to 1.4±0.1. TBUT improved by +93% (n=38; P<0.0001) and +425% (n=42; P<0.0001) for sites 1 and 2, respectively. SPEED, MGS, and CFS improved by −55% (n=80; P<0.0001), −36% (n=80; P<0.0001), and −58% (n=38; P<0.0001), respectively. In 20 eyes with abnormally elevated TFO at BL, TFO improved by −7% (n=20; P<0.005). LLT did not change (n=38; P=0.88). Conclusion In subjects with moderate to severe MGD, IPL combined with MGX reduced the number and severity of symptoms and signs of DED. Except for LLT, all examined outcome measures significantly improved after 15 weeks. These results support the efficacy of IPL + MGX in relieving both signs and symptoms of DED secondary to MGD. PMID:28496300

  16. Effects of hydroxypyridine derivatives mexidol and emoxypin on the reparative processes in rabbit eye on the models of corneal epithelial defect and conjunctival ischemia.

    PubMed

    Chesnokova, N B; Beznos, O V; Pavlenko, T A; Zabozlaev, A A; Pavlova, M V

    2015-01-01

    Deepithelialization of the cornea (diameter 7 mm) was performed in rabbits and the rate of defect epithelialization was evaluated. Conjunctival ischemia was modeled by application of graduated alkaline burn. Antioxidant activity and content of nitrates and nitrites was measured in the tear fluid before and after burn by chemiluminescence and Griess methods, respectively. Emoxypin and mexidol promoted healing of corneal epithelial defect at the stage of epitheliocyte migration to the defect area and at the stage of their proliferation, respectively. After treatment with both agents, the area of conjunctival ischemia decreased more rapidly, but the efficiency of mexidol was higher. Antioxidant activity and content of products of NO metabolism in tear fluid decreased after burn. Mexidol, but not emoxypin, increased these parameters. Thus, mexidol and emoxypin have different effects on corneal epithelialization and conjunctival ischemia and effects of mexidol are more pronounced.

  17. [Studies on the lymph drainage of the eye. 1. Quantitative registration of the lymph drainage from the orbita of the rabbit with radioactive tracers (author's transl)].

    PubMed

    Grüntzig, J; Schicha, H; Kiem, J; Becker, V; Feinendegen, L E

    1977-05-01

    For the investigation on the lymph drainage from the orbita 99mTc-microcolloid, 99mTc-albumin and 198Au-colloid have been injected into the retrobulbar space of 24 rabbits. Measurements of the activity's distribution have been made in vivo with an Anger type camera (pho-Gamma-IV Hp, Searle Nuclear Chicago) and in vitro after section with a sodium iodine crystal well counter (Clinimat-200, Picker). A significant concentration of the activity could be observed for the most part in the equilateral Lymphonoduli cervicales profundi and superficiales and for the less part also in the equilateral Lymphonoduli mandibulares and contralateral Lymphonoduli cervicales profoundi. Furthermore significant activities could be pointed out in the optic nerves as well as in the contralateral retrobulbar space. The data substantiate a lymph drainage from the orbita as well as a partly reverse "prelymphatic-lymphatic" flow and are of importance for discussions about lymphostatic ophthalmopathy and sympathetic ophthalmitis. For application on man 99mTc-microcolloid (Lymphoscint) shoud be preferred, because with this tracer 1. the lymph drainage can be measured quantitatively quite exactly by extern measurement with the Anger-camera, 2. the allowable radiation dosis for the lens is lying between 0.5-1.0 rad/mCi.

  18. Neck/shoulder discomfort due to visually demanding experimental near work is influenced by previous neck pain, task duration, astigmatism, internal eye discomfort and accommodation

    PubMed Central

    Forsman, Mikael; Richter, Hans O.

    2017-01-01

    Visually demanding near work can cause eye discomfort, and eye and neck/shoulder discomfort during, e.g., computer work are associated. To investigate direct effects of experimental near work on eye and neck/shoulder discomfort, 33 individuals with chronic neck pain and 33 healthy control subjects performed a visual task four times using four different trial lenses (referred to as four different viewing conditions), and they rated eye and neck/shoulder discomfort at baseline and after each task. Since symptoms of eye discomfort may differ depending on the underlying cause, two categories were used; internal eye discomfort, such as ache and strain, that may be caused by accommodative or vergence stress; and external eye discomfort, such as burning and smarting, that may be caused by dry-eye disorders. The cumulative performance time (reflected in the temporal order of the tasks), astigmatism, accommodation response and concurrent symptoms of internal eye discomfort all aggravated neck/shoulder discomfort, but there was no significant effect of external eye discomfort. There was also an interaction effect between the temporal order and internal eye discomfort: participants with a greater mean increase in internal eye discomfort also developed more neck/shoulder discomfort with time. Since moderate musculoskeletal symptoms are a risk factor for more severe symptoms, it is important to ensure a good visual environment in occupations involving visually demanding near work. PMID:28832612

  19. Improvement of the Bovine Corneal Opacity and Permeability (BCOP) assay as an in vitro alternative to the Draize rabbit eye irritation test.

    PubMed

    Verstraelen, Sandra; Jacobs, An; De Wever, Bart; Vanparys, Philippe

    2013-06-01

    Measurement of ocular irritancy is a necessary step in the safety evaluation of both industrial and consumer products. Assessment of the acute eye irritation potential is therefore part of the international regulatory requirements for testing of chemicals. The Bovine Corneal Opacity and Permeability (BCOP) assay is generally accepted as a valid in vitro alternative method to the Draize eye irritation test to detect corrosive and severe eye irritants (category 1), but has not proven sensitive enough to discriminate accurately moderate (category 2A/2B) to mild and non-irritating compounds. In the currently accepted BCOP assay, opacity is determined by the amount of light transmission through the cornea, and permeability is determined by the amount of sodium fluorescein dye that passes through all corneal cell layers. Both measurements are used to assign an In Vitro Irritancy Score (IVIS) for prediction of the in vivo ocular irritation potential of a test substance. Nowadays, opacity is measured by an OP-KIT opacitometer providing a center-weighted reading of light transmission by measuring changes in voltage when the transmission of white light passes through the cornea alters. As a consequence, this may underestimate opacity that develops as spots or heterogeneous opaque areas on the periphery of an isolated cornea. A prototype of a laser light-based opacitometer (PLLBO) allowing better measurement of opacities was developed by Van Goethem et al. (2010). This new device showed improved sensitivity to detect subtle changes in corneal transparency. Furthermore, the new opacitometer allowed the analysis of the complete corneal surface and was able to detect more efficiently opaque spots located along the sides of the excised corneas. A further improved prototype of the PLLBO was constructed in combination with a camera and a speckle noise reducer. Treatment conditions of the corneas in the cornea holders were optimized in order to mimic more the real in vivo situation

  20. The Effect of Sensory Uncertainty Due to Amblyopia (Lazy Eye) on the Planning and Execution of Visually-Guided 3D Reaching Movements

    PubMed Central

    Niechwiej-Szwedo, Ewa; Goltz, Herbert C.; Chandrakumar, Manokaraananthan; Wong, Agnes M. F.

    2012-01-01

    Background Impairment of spatiotemporal visual processing in amblyopia has been studied extensively, but its effects on visuomotor tasks have rarely been examined. Here, we investigate how visual deficits in amblyopia affect motor planning and online control of visually-guided, unconstrained reaching movements. Methods Thirteen patients with mild amblyopia, 13 with severe amblyopia and 13 visually-normal participants were recruited. Participants reached and touched a visual target during binocular and monocular viewing. Motor planning was assessed by examining spatial variability of the trajectory at 50–100 ms after movement onset. Online control was assessed by examining the endpoint variability and by calculating the coefficient of determination (R2) which correlates the spatial position of the limb during the movement to endpoint position. Results Patients with amblyopia had reduced precision of the motor plan in all viewing conditions as evidenced by increased variability of the reach early in the trajectory. Endpoint precision was comparable between patients with mild amblyopia and control participants. Patients with severe amblyopia had reduced endpoint precision along azimuth and elevation during amblyopic eye viewing only, and along the depth axis in all viewing conditions. In addition, they had significantly higher R2 values at 70% of movement time along the elevation and depth axes during amblyopic eye viewing. Conclusion Sensory uncertainty due to amblyopia leads to reduced precision of the motor plan. The ability to implement online corrections depends on the severity of the visual deficit, viewing condition, and the axis of the reaching movement. Patients with mild amblyopia used online control effectively to compensate for the reduced precision of the motor plan. In contrast, patients with severe amblyopia were not able to use online control as effectively to amend the limb trajectory especially along the depth axis, which could be due to their

  1. The effect of sensory uncertainty due to amblyopia (lazy eye) on the planning and execution of visually-guided 3D reaching movements.

    PubMed

    Niechwiej-Szwedo, Ewa; Goltz, Herbert C; Chandrakumar, Manokaraananthan; Wong, Agnes M F

    2012-01-01

    Impairment of spatiotemporal visual processing in amblyopia has been studied extensively, but its effects on visuomotor tasks have rarely been examined. Here, we investigate how visual deficits in amblyopia affect motor planning and online control of visually-guided, unconstrained reaching movements. Thirteen patients with mild amblyopia, 13 with severe amblyopia and 13 visually-normal participants were recruited. Participants reached and touched a visual target during binocular and monocular viewing. Motor planning was assessed by examining spatial variability of the trajectory at 50-100 ms after movement onset. Online control was assessed by examining the endpoint variability and by calculating the coefficient of determination (R(2)) which correlates the spatial position of the limb during the movement to endpoint position. Patients with amblyopia had reduced precision of the motor plan in all viewing conditions as evidenced by increased variability of the reach early in the trajectory. Endpoint precision was comparable between patients with mild amblyopia and control participants. Patients with severe amblyopia had reduced endpoint precision along azimuth and elevation during amblyopic eye viewing only, and along the depth axis in all viewing conditions. In addition, they had significantly higher R(2) values at 70% of movement time along the elevation and depth axes during amblyopic eye viewing. Sensory uncertainty due to amblyopia leads to reduced precision of the motor plan. The ability to implement online corrections depends on the severity of the visual deficit, viewing condition, and the axis of the reaching movement. Patients with mild amblyopia used online control effectively to compensate for the reduced precision of the motor plan. In contrast, patients with severe amblyopia were not able to use online control as effectively to amend the limb trajectory especially along the depth axis, which could be due to their abnormal stereopsis.

  2. Effects of genipin corneal crosslinking in rabbit corneas.

    PubMed

    Avila, Marcel Y; Narvaez, Mauricio; Castañeda, Juan P

    2016-07-01

    To evaluate the effect of genipin, a natural crosslinking agent, in rabbit eyes. Department of Ophthalmology, Universidad Nacional de Colombia Centro de Tecnologia Oftalmica, Bogotá, Colombia. Experimental study. Ex vivo rabbit eyes (16; 8 rabbits) were treated with genipin 1.00%, 0.50%, and 0.25% for 5 minutes with a vacuum device to increase corneal permeability. Penetration was evaluated using Scheimpflug pachymetry (Pentacam). In the in vivo model (20 rabbits; 1 eye treated, 1 eye with vehicle), corneas were crosslinked with genipin as described. Corneal curvature, corneal pachymetry, and intraocular pressure (IOP) assessments as well as slitlamp examinations were performed 0, 7, 30, and 60 days after treatment. In the ex vivo model, Scheimpflug pachymetry showed deep penetration in the rabbit corneas with an increase in corneal density and a dose-dependent relationship. Corneal flattening was observed in treated eyes (mean 4.4 diopters ± 0.5 [SD]) compared with the control eyes. Pachymetry and IOP were stable in all evaluations. No eye showed toxicity in the anterior chamber or in the lens. Corneal crosslinking induced by genipin produced significant flattening of the cornea with no toxicity in rabbit eyes. This crosslinking could be useful in the treatment of corneal ectasia and in the modification of corneal curvature. None of the authors has a financial or proprietary interest in any material or method mentioned. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  3. LASIK Eye Surgery

    MedlinePlus

    ... conditions. These conditions include: Autoimmune disorders, such as rheumatoid arthritis Immunodeficiency conditions caused by immunosuppressive medications or HIV Persistent dry eyes Unstable vision due to medications, hormonal changes, pregnancy, breast-feeding or age Several eye conditions, such ...

  4. Effect of the Rho-Associated Kinase Inhibitor Eye Drop (Ripasudil) on Corneal Endothelial Wound Healing.

    PubMed

    Okumura, Naoki; Okazaki, Yugo; Inoue, Ryota; Kakutani, Kazuya; Nakano, Shinichiro; Kinoshita, Shigeru; Koizumi, Noriko

    2016-03-01

    Ripasudil (Glanatec), a selective rho-associated coiled coil-containing protein kinase (ROCK) inhibitor, was approved as a glaucoma and ocular hypertension treatment in Japan in 2014. The purpose of this study was to investigate the feasibility of using ripasudil eye drops to treat corneal endothelial injuries. Cultured human corneal endothelial cells (HCECs) were treated with ripasudil, and 5-bromo-2'-deoxyuridine (BrdU) incorporation was evaluated by ELISA. A rabbit corneal endothelial damage model was also created by mechanically scraping the corneal endothelium, followed by topical ripasudil eye drop application for 2 weeks. The anterior segment was evaluated by slit-lamp microscopy, and central corneal thickness was measured by ultrasound pachymetry. Corneal specimens were evaluated by phalloidin staining and immunohistochemical analysis using antibodies against Ki67, N-cadherin, and Na+/K+-ATPase. Many more BrdU-positive cells were observed among the HCECs treated with ripasudil (0.3-30 μM) than among the control HCECs. Ripasudil-treated eyes in a rabbit model showed 91.5 ± 2.0% Ki67-positive cells after 48 hours, whereas control eyes showed 52.6 ± 1.3%. Five of six corneas became transparent in ripasudil-treated eyes, whereas zero of six corneas became transparent in the control eyes. Regenerated cell densities were higher in the eyes treated with ripasudil than in eyes treated with vehicle. Eyes treated with ripasudil expressed N-cadherin and Na+/K+-ATPase in almost all CECs, whereas this expression was decreased in control eyes. Ripasudil promoted corneal endothelial wound healing, supporting its development as eye drops for treating acute corneal endothelial damage due to eye surgeries, especially cataract surgery.

  5. 16 CFR 1500.42 - Test for eye irritants.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Test for eye irritants. 1500.42 Section 1500... eye irritants. (a)(1) Six albino rabbits are used for each test substance. Animal facilities for such... materials that might produce eye irritation. Both eyes of each animal in the test group shall be...

  6. 16 CFR 1500.42 - Test for eye irritants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Test for eye irritants. 1500.42 Section 1500... eye irritants. (a)(1) Six albino rabbits are used for each test substance. Animal facilities for such... materials that might produce eye irritation. Both eyes of each animal in the test group shall be...

  7. Development and validation of a synthetic eye and orbit for estimating the potential for globe rupture due to specific impact conditions.

    PubMed

    Kennedy, Eric A; Inzana, Jason A; McNally, Craig; Duma, Stefan M; Depinet, Paul J; Sullenberger, Kristopher H; Morgan, Craig R; Brozoski, Frederick T

    2007-10-01

    The Facial and Ocular CountermeasUre Safety (FOCUS) headform is intended to aid safety equipment design in order to reduce the risk of eye and facial injuries. The purpose of this paper is to present a three part study that details the development and validation of the FOCUS synthetic eye and orbit and the corresponding eye injury criteria. The synthetic eye and orbit were designed to simulate the force-deflection response to in-situ dynamic impacts. In part I, the force-deflection response of the eye was determined based on dynamic blunt impact tests with human eyes. These data were used to validate the appropriate material for a biofidelic synthetic eye. In part II, force-deflection corridors developed from ten dynamic in-situ eye impacts were used to validate the design and material selections for the synthetic orbit assembly. In part III, 82 experimental tests on the FOCUS headform were conducted using steel BB projectiles to develop a conservative injury risk criteria for the FOCUS headform based on the response of the eye load cell. Injury criterion for globe rupture is strongly correlated to the data from the FOCUS eye load cell (R(2) = 0.995). Based on the response of the FOCUS eye load cell, a 50% risk of globe rupture from a 4.5 mm BB impact is shown to be 107 N. With a biofidelic synthetic eye and this projectile-specific injury criteria, the FOCUS headform can be used to conservatively evaluate the risk of globe rupture from > or = 4.5 mm diameter projectile impacts to the eye.

  8. Rabbit models for continuous curvilinear capsulorhexis instruction.

    PubMed

    Ruggiero, Jason; Keller, Christopher; Porco, Travis; Naseri, Ayman; Sretavan, David W

    2012-07-01

    To develop a rabbit model for continuous curvilinear capsulorhexis (CCC) instruction. University of California San Francisco, San Francisco, California, USA. Experimental study. Isolated rabbit lenses were immersed in 2% to 8% paraformaldehyde (PFA) fixative from 15 minutes to 6 hours. Rabbit eyes were treated by substituting aqueous with 2% to 4% PFA for 30 minutes to 6 hours, followed by washes with a balanced salt solution. Treated lenses and eyes were held in purpose-designed holders using vacuum. A panel of 6 cataract surgeons with 5 to 15 years of experience performed CCC on treated lenses and eyes and responded to a questionnaire regarding the utility of these models for resident teaching using a 5-item Likert scale. The expert panel found that rabbit lenses treated with increasing amounts of fixative simulated CCC on human lens capsules from the third to the seventh decade of life. The panel also found fixative-treated rabbit eyes to simulate some of the experience of CCC within the human anterior chamber but noted a shallower anterior chamber depth, variation in pupil size, and corneal clouding under some treatment conditions. Experienced cataract surgeons who performed CCC on these rabbit models strongly agreed that isolated rabbit lenses treated with fixative provide a realistic simulation of CCC in human patients and that both models were useful tools for capsulorhexis instruction. Results indicate that rabbit lenses treated with 8% PFA for 15 minutes is a model with good fidelity for CCC training. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  9. Eye Cancer

    MedlinePlus

    ... Cancer > Eye Cancer > Eye Cancer: Overview Request Permissions Eye Cancer: Overview Approved by the Cancer.Net Editorial ... trained to treat intraocular cancer. Parts of the eye The eye is the organ that collects light ...

  10. Eye Infections

    MedlinePlus

    Your eyes can get infections from bacteria, fungi, or viruses. Eye infections can occur in different parts of the eye and can affect just one eye or both. Two common eye infections are Conjunctivitis - also known as pinkeye. Conjunctivitis is ...

  11. Immunosuppression abrogates resistance of young rabbits to Rabbit Haemorrhagic Disease (RHD)

    PubMed Central

    2014-01-01

    Rabbit Haemorrhagic Disease (RHD) is caused by a calicivirus (RHDV) that kills 90% of infected adult European rabbits within 3 days. Remarkably, young rabbits are resistant to RHD. We induced immunosuppression in young rabbits by treatment with methylprednisolone acetate (MPA) and challenged the animals with RHDV by intramuscular injection. All of these young rabbits died within 3 days of infection due to fulminant hepatitis, presenting a large number of RHDV-positive dead or apoptotic hepatocytes, and a significant seric increase in cytokines, features that are similar to those of naïve adult rabbits infected by RHDV. We conclude that MPA-induced immunosuppression abrogates the resistance of young rabbits to RHD, indicating that there are differences in the innate immune system between young and adult rabbits that contribute to their distinct resistance/susceptibility to RHDV infection. PMID:24490832

  12. Immunosuppression abrogates resistance of young rabbits to Rabbit Haemorrhagic Disease (RHD).

    PubMed

    Marques, Raquel M; Teixeira, Luzia; Aguas, Artur P; Ribeiro, Joana C; Costa-e-Silva, António; Ferreira, Paula G

    2014-02-04

    Rabbit Haemorrhagic Disease (RHD) is caused by a calicivirus (RHDV) that kills 90% of infected adult European rabbits within 3 days. Remarkably, young rabbits are resistant to RHD. We induced immunosuppression in young rabbits by treatment with methylprednisolone acetate (MPA) and challenged the animals with RHDV by intramuscular injection. All of these young rabbits died within 3 days of infection due to fulminant hepatitis, presenting a large number of RHDV-positive dead or apoptotic hepatocytes, and a significant seric increase in cytokines, features that are similar to those of naïve adult rabbits infected by RHDV. We conclude that MPA-induced immunosuppression abrogates the resistance of young rabbits to RHD, indicating that there are differences in the innate immune system between young and adult rabbits that contribute to their distinct resistance/susceptibility to RHDV infection.

  13. Ocular and systemic toxicity of intravitreal topotecan in rabbits for potential treatment of retinoblastoma.

    PubMed

    Buitrago, Emiliano; Del Sole, María José; Torbidoni, Ana; Fandino, Adriana; Asprea, Marcelo; Croxatto, J O; Chantada, Guillermo L; Bramuglia, Guillermo F; Schaiquevich, Paula

    2013-03-01

    Treatment of intraocular retinoblastoma with vitreous seeding is a challenge. Different routes of chemotherapy administration have been explored in order to attaining pharmacological concentrations into the posterior chamber. Intravitreal drug injection is a promissing route for maximum bioavailability to the vitreous but it requires a well defined dose for achieving tumor control while limited toxicity to the retina. Topotecan proved to be a promising agent for retinoblastoma treatment due to its pharmacological activity and limited toxicity. High and prolonged concentrations were achieved in the rabbit vitreous after 5 μg of intravitreal topotecan. However, whether a lower dose could achieve potentially therapeutic levels remained to be determined. Thus, we here study the pharmacokinetics of topotecan after 0.5 μg and the toxicity profile of intravitreal topotecan in the rabbit eye as a potential treatment of retinoblastoma. A cohort of rabbits was used to study topotecan disposition in the vitreous after a single dose of 0.5 μg of intravitreal topotecan. In addition, an independent cohort of non-tumor bearing rabbits was employed to evaluate the clinical and retinal toxicity after four weekly injections of two different doses of intravitreal topotecan (Group A, 5 μg/dose; Group B, 0.5 μg/dose) to the right eye of each animal. The same volume (0.1 ml) of normal saline was administered to the left eye as control. A third group of rabbits (Group C) served as double control (both eyes injected with normal saline). Animals were weekly evaluated for clinical and hematologic values and ocular evaluations were performed with an inverse ophthalmoscope to establish potential topotecan toxicity. Weekly controls included topotecan quantitation in plasma of all rabbits. Electroretinograms (ERGs) were recorded before and after topotecan doses. One week after the last injection, topotecan concentrations were measured in vitreous of all eyes and samples for retinal

  14. Eye pain

    MedlinePlus

    Ophthalmalgia; Pain - eye ... Pain in the eye can be an important symptom of a health problem. Make sure you tell your health care provider if you have eye pain that does not go away. Tired eyes or ...

  15. Rabbit hematology.

    PubMed

    Marshall, Kemba L

    2008-09-01

    Using laboratory animal medicine as an established resource, companion animal veterinarians have access to many physiologic and basic science studies that we can now merge with our clinical impressions. By working with reference laboratories, companion animal veterinarians are poised to accelerate our knowledge of the normal rabbit rapidly. The aim of this article is to discuss normal hematopoiesis and infectious and metabolic diseases that specifically target the hemolymphatic system. Additionally, photographic representation of cell types is provided.

  16. Onset and duration of visual acuity improvement after dexamethasone intravitreal implant in eyes with macular edema due to retinal vein occlusion.

    PubMed

    Kuppermann, Baruch D; Haller, Julia A; Bandello, Francesco; Loewenstein, Anat; Jiao, Jenny; Li, Xiao-Yan; Whitcup, Scott M

    2014-09-01

    To evaluate the onset and duration of improvement in best-corrected visual acuity (BCVA) in eyes treated with dexamethasone intravitreal implant 0.7 mg (DEX implant) for macular edema after branch or central retinal vein occlusion. Post hoc analysis of data from 2 previously reported multicenter, 6-month, randomized sham-controlled clinical trials. Patients received a single DEX implant (n = 427) or sham procedure (n = 426) in the study eye. The primary endpoint was the percentage of eyes with ≥ 15-letter improvement in BCVA from baseline at postimplant Day 7. The baseline mean BCVA was 20/80. At Day 7, 10.3% of DEX implant-treated eyes versus 4.0% of sham-treated eyes (P < 0.001) had ≥ 15-letter improvement in the BCVA, and 27.2% of DEX implant-treated eyes versus 10.6% of sham-treated eyes had ≥ 10-letter improvement (P < 0.001). The mean improvement at Day 7 was 5.3 letters (branch retinal vein occlusion, 5.1; and central retinal vein occlusion, 5.8) with DEX implant and 1.6 letters (branch retinal vein occlusion, 2.3; and central retinal vein occlusion, 0.1) with sham (P < 0.001). The mean time from initial observation of ≥ 15-letter BCVA gain to the last observation of ≥ 15-letter BCVA gain was 70 days. Dexamethasone intravitreal implant treatment led to improvement in BCVA compared with sham procedure as early as postimplant Day 7. The duration of ≥ 3-line improvement was typically 2 to 3 months.

  17. Rabbit Models for Studying Human Infectious Diseases

    PubMed Central

    Peng, Xuwen; Knouse, John A; Hernon, Krista M

    2015-01-01

    Using an appropriate animal model is crucial for mimicking human disease conditions, and various facets including genetics, anatomy, and pathophysiology should be considered before selecting a model. Rabbits (Oryctolagus cuniculus) are well known for their wide use in production of antibodies, eye research, atherosclerosis and other cardiovascular diseases. However, a systematic description of the rabbit as primary experimental models for the study of various human infectious diseases is unavailable. This review focuses on the human infectious diseases for which rabbits are considered a classic or highly appropriate model, including AIDS (caused by HIV1), adult T-cell leukemia–lymphoma (human T-lymphotropic virus type 1), papilloma or carcinoma (human papillomavirus) , herpetic stromal keratitis (herpes simplex virus type 1), tuberculosis (Mycobacterium tuberculosis), and syphilis (Treponema pallidum). In addition, particular aspects of the husbandry and care of rabbits used in studies of human infectious diseases are described. PMID:26678367

  18. Phospholamban Overexpression in Transgenic Rabbits

    PubMed Central

    Pattison, J. Scott; Waggoner, Jason R.; James, Jeanne; Martin, Lisa; Gulick, James; Osinska, Hanna; Klevitsky, Raisa; Kranias, Evangelia G.; Robbins, Jeffrey

    2008-01-01

    There has been considerable interest in pursuing phospholamban as a putative therapeutic target for overcoming depressed calcium handling in human heart failure. Studies predominantly done in mice have shown that phospholamban is a key regulator of sarcoplasmic reticulum calcium cycling and cardiac function. However, mice differ significantly from humans in how they regulate calcium, whereas rabbits better recapitulate human cardiac function and calcium handling. To investigate phospholamban’s role in the rabbit heart, transgenic rabbits that overexpressed wild-type phospholamban in the ventricular cardiomyocytes and slow-twitch skeletal muscles were generated. Rabbits expressing high levels of phospholamban were not viable due to severe skeletal muscle wasting, the onset of cardiac pathology and early death. A viable transgenic line exhibited a 30% increase in PLN protein levels in the heart. These animals showed isolated foci of cardiac pathology, but cardiac function as well as the response to β-adrenergic stimulation were normal. SR-calcium uptake measurements showed that the transgenic hearts had the expected reduced affinity for calcium. The data show that phospholamban-overexpressing transgenic rabbits differ markedly in phenotype from analogous transgenic mice in that rabbits are quite sensitive to alterations in phospholamban levels. Exceeding a relatively narrow window of phospholamban expression results in significant morbidity and early death. PMID:17882530

  19. Pharmacological profile of oxaprozin eye drops.

    PubMed

    Bucolo, Claudio; Maltese, Adriana

    2002-02-01

    The effects of eye drops containing a propionic acid derivative (oxaprozin) at 0.1% concentration on ocular inflammation produced by sodium arachidonate in the rabbit's eye were evaluated. Furthermore, the aqueous bioavailability of the drug formulation in the uninflamed and inflamed eyes was evaluated. Oxaprozin eye drops significantly reduced the signs of ocular inflammation elicited by sodium arachidonate on conjunctiva and iris. Oxaprozin treatment significantly reduced the levels of polymorphonuclear leukocytes and protein concentration in aqueous samples obtained from the eyes treated with arachidonate. Present data suggest, for the first time, that oxaprozin may be employed topically to prevent ocular reactions where the arachidonic acid cascade is activated.

  20. Pharmacokinetics of trimethoprim (TMP) in normal and febrile rabbits.

    PubMed

    Ladefoged, O

    1977-11-01

    The pharmacokinetics of trimethoprim (TMP) were investigated in normal and febrile rabbits. The half-life of TMP in rabbits is about 40 minutes and no differences were found between the half-life in normal and febrile rabbits. A significantly greater volume of distribution of TMP, however, was found in the febrile rabbits. Analysis according to the two-compartment model showed that the differences are due to a change in the distribution of TMP towards the peripheral compartments.

  1. Smooth pursuit adaptation (SPA) exhibits features useful to compensate changes in the properties of the smooth pursuit eye movement system due to usage.

    PubMed

    Dash, Suryadeep; Thier, Peter

    2013-01-01

    Smooth-pursuit adaptation (SPA) refers to the fact that pursuit gain in the early, still open-loop response phase of the pursuit eye movement can be adjusted based on experience. For instance, if the target moves initially at a constant velocity for ~100-200 ms and then steps to a higher velocity, subjects learn to up-regulate the pursuit gain associated with the initial target velocity (gain-increase SPA) in order to reduce the retinal error resulting from the velocity step. Correspondingly, a step to a lower target velocity leads to a decrease in gain (gain-decrease SPA). In this study we demonstrate that the increase in peak eye velocity during gain-increase SPA is a consequence of expanding the duration of the eye acceleration profile while the decrease in peak velocity during gain-decrease SPA results from reduced peak eye acceleration but unaltered duration. Furthermore, we show that carrying out stereotypical smooth pursuit eye movements elicited by constant velocity target ramps for several hundred trials (=test of pursuit resilience) leads to a clear drop in initial peak acceleration, a reflection of oculomotor and/or cognitive fatigue. However, this drop in acceleration gets compensated by an increase in the duration of the acceleration profile, thereby keeping initial pursuit gain constant. The compensatory expansion of the acceleration profile in the pursuit resilience experiment is reminiscent of the one leading to gain-increase SPA, suggesting that both processes tap one and the same neuronal mechanism warranting a precise acceleration-duration trade-off. Finally, we show that the ability to adjust acceleration duration during pursuit resilience depends on the integrity of the oculomotor vermis (OMV) as indicated by the complete loss of the duration adjustment following a surgical lesion of the OMV in one rhesus monkey we could study.

  2. RABBIT POX

    PubMed Central

    Rosahn, Paul D.; Hu, Ch'uan-K'uei

    1935-01-01

    Observations on an epidemic of rabbit pox occurring in an isolated animal room during the winter of 1933–34 are reported. The clinical manifestations, consisting of a generalized papular eruption involving the skin and mucous membranes, together with blepharitis, ophthalmia, nasal discharge and lymphadenopathy were essentially similar to those noted in a pox epidemic of the previous year. This was true in general also of the pathological findings except that vacuolization, local necrosis and vesicle formation were seen in the epidermis, while in the previous year the microscopic pathology in the skin was confined to the corium. Evidence was presented indicating that the infection can be transmitted through the medium of a personal carrier, and that transmission in this manner can occur during the incubation period or before a definite diagnosis is possible. The findings also demonstrated that the etiological agents responsible for the disease reported here and that of the previous year were immunologically related, and that the immunity in recovered animals effectively persisted during the entire period for which data are available, 9 to 12 months. It appeared also that young animals suckling an immune doe were more refractory to the development of the lesions of rabbit pox than were the young of susceptible does. PMID:19870418

  3. Corneal wound healing after ultraviolet-A/riboflavin collagen cross-linking: a rabbit study.

    PubMed

    Salomão, Marcella Q; Chaurasia, Shyam S; Sinha-Roy, Abhijit; Ambrósio, Renato; Esposito, Andrew; Sepulveda, Ricardo; Agrawal, Vandana; Wilson, Steven E

    2011-06-01

    To investigate corneal wound healing following ultraviolet-A (UVA)/riboflavin corneal collagen cross-linking (CXL) in rabbit corneas. Thirty-six rabbits were enrolled in the study. Animals were divided into three treatment groups and corneas were analyzed at 24 hours and 4 weeks postoperatively. Thus, each group had 6 rabbits at each time point. Treatment groups were: 1) standard UVA+riboflavin CXL, 2) UVA alone, and 3) riboflavin alone. One eye of each rabbit served as an untreated control eye. TUNEL assay was performed to detect stromal cell apoptosis. Immunocytochemistry was performed to detect the inflammatory marker CD11b expressed in monocytes and the alpha-smooth muscle actin (SMA) marker expressed in myofibroblasts. At 24 hours, corneas from the UVA+riboflavin CXL group had significantly more apoptosis than the UVA alone and riboflavin alone groups. Eyes from all three groups had significantly more inflammatory cell influx into the cornea than unwounded controls. Four weeks after the procedure, many corneas in the UVA+riboflavin CXL group had mild haze, but very few SMA-positive myofibroblasts could be detected in the central cornea. Riboflavin+UVA CXL triggers more anterior keratocyte apoptosis than corneal scrape with UVA alone or riboflavin alone. Inflammation monitored by the monocyte marker CD11b was present, but not statistically different among the three groups. Very little myofibroblast generation could be detected after UVA+riboflavin CXL, indicating that the mild stromal haze associated with this procedure is normally related to transient corneal fibroblast generation rather than more persistent haze due to generation of myofibroblasts. Copyright 2011, SLACK Incorporated.

  4. A nanoparticle formulation reduces the corneal toxicity of indomethacin eye drops and enhances its corneal permeability.

    PubMed

    Nagai, Noriaki; Ito, Yoshimasa; Okamoto, Norio; Shimomura, Yoshikazu

    2014-05-07

    Indomethacin (IMC) has been shown to reduce post-operative inflammation and to decrease intraocular irritation after cataract extraction and in cystoid macular edema; however, the clinical use of its most commonly used eye drops is limited due to topical side-effects that include burning sensation, irritation and epithelial keratitis. It is known that decreasing direct cell stimulation and reducing the amount applied via increasing bioavailability are useful for improving these issues. In this study, we designed ophthalmic formulations containing 0.5% IMC nanoparticles using zirconia beads and Bead Smash 12 (IMCnano eye drops; particle size 76 ± 59 nm, mean ± S.D.), and investigated the corneal toxicity of these IMCnano eye drops. IMCnano eye drops are tolerated better by a human cornea epithelial cell line (HCE-T) than commercially available NDSAIDs preparations (IMC, pranoprofen, diclofenac, bromfenac and nepafenac eye drops), and corneal wound healing in rat eyes with debrided corneal epithelium instilled with IMCnano eye drops is significantly better than that of eyes instilled with commercially available IMC eye drops. In addition, the accumulation of IMC in HCE-T cells treated with the IMCnano eye drops for 30 min was 19.9% that of the accumulation from commercially available IMC eye drops. On the other hand, the corneal penetration of IMC from IMCnano eye drops was significantly greater than in the case of the commercially available IMC eye drops in both in vivo and in vitro studies using rabbit corneas. Taken together, we hypothesize that a nanoparticle formulation reduces the corneal toxicity of IMC eye drops, probably because the accumulation of IMC from IMCnano eye drops in the eye is lower than that from commercially available IMC eye drops. In addition, the nanoparticle formulation may allow a decrease in the amount of IMC used due to the increase in bioavailability, resulting in reduced drug toxicity. These findings provide significant information

  5. Pulmonary interstitial pressure in premature rabbits.

    PubMed

    Miserocchi, G; Poskurica, B H; del Fabbro, M; Crisafulli, B

    1995-12-01

    By micropuncture technique we measured pulmonary interstitial pressure (Pip) from birth up to 6 h postnatal age in anesthetized and paralyzed cesarian delivered term (31 days gestation) and premature (27 to 30 days gestation) rabbits. In term cesarian delivered rabbits Pip followed the time course of vaginally delivered rabbits, namely, it increased from about zero at birth up to about 5 cmH2O at 2 h, as a result of alveolar fluid reabsorption, subsequently it decreased becoming subatmospheric due to progressive interstitial fluid drainage. In ventilated lung regions of premature rabbits, Pip also peaked to about 5 cmH2O at 2 h but its subsequent decrease was markedly slowed down while in atelectatic regions of premature rabbits Pip remained slightly subatmospheric. Up to 6 h, the wet/dry weight ratio of the lung was higher in premature relative to vaginally and cesarian delivered term rabbits (at birth 8.4 +/- 0.9 vs. 7.5 +/- 0.8). In 29-31 days rabbits, plasma protein concentration at birth was 3.6 +/- 0.5 g/dl (within 95% confidence limits for vaginally delivered rabbits, considered as control) while in 27-28 days rabbit it was 3.1 +/- 0.4 g/dl (at the lower edge of control confidence limits). In the first postnatal hours, the increase in Pip favoured fluid reabsorption into pulmonary microcirculation in term cesarian delivered rabbits and in ventilated regions of premature rabbits. Conversely, in the atelectatic regions of premature rabbits the unchanged Pip value in the postnatal hours favours fluid filtration from microcirculation into lung interstitium.

  6. Eye Diseases

    MedlinePlus

    ... the back of the eye Macular degeneration - a disease that destroys sharp, central vision Diabetic eye problems ... defense is to have regular checkups, because eye diseases do not always have symptoms. Early detection and ...

  7. Eye Injuries

    MedlinePlus

    The structure of your face helps protect your eyes from injury. Still, injuries can damage your eye, sometimes severely enough that you could lose your vision. Most eye injuries are preventable. If you play sports or ...

  8. Eye Cancer

    MedlinePlus

    Cancer of the eye is uncommon. It can affect the outer parts of the eye, such as the eyelid, which are made up ... adults are melanoma and lymphoma. The most common eye cancer in children is retinoblastoma, which starts in ...

  9. Eye Allergies

    MedlinePlus

    ... Sep. 01, 2016 Eye allergies, also called allergic conjunctivitis, are quite common. They occur when the eyes ... can tear and burn. Unlike other kinds of conjunctivitis, eye allergies are not spread from person to ...

  10. Watery eyes

    MedlinePlus

    ... the most common causes of excess tearing is dry eyes . Drying causes the eyes to become uncomfortable, which stimulates the body to produce too many tears. One of the main tests for tearing is to check whether the eyes ...

  11. Partial trisomy due to a de novo duplication 22q11.1-22q13.1: a cat-eye syndrome variant with brain anomalies.

    PubMed

    Karcaaltincaba, D; Ceylaner, S; Ceylaner, G; Dalkilic, S; Karli-Oguz, K; Kandemir, O

    2010-01-01

    We report a case of partial trisomy 22q with de novo duplication of chromosomal region 22q11.1-22q13.1, also confirmed by microarray comparative genomic hybridization (Array-CGH) analysis. The fetus had interhemispheric cyst and corpus callosum agenesis diagnosed by MRI which has not been reported in the literature. This novel phenotype differs from the reported cat eye syndromes by the absence of heart defects and the presence of brain anomalies.

  12. Near-infrared spectroscopy (NIRS)-based eyes-closed brain-computer interface (BCI) using prefrontal cortex activation due to mental arithmetic

    PubMed Central

    Shin, Jaeyoung; Müller, Klaus-R; Hwang, Han-Jeong

    2016-01-01

    We propose a near-infrared spectroscopy (NIRS)-based brain-computer interface (BCI) that can be operated in eyes-closed (EC) state. To evaluate the feasibility of NIRS-based EC BCIs, we compared the performance of an eye-open (EO) BCI paradigm and an EC BCI paradigm with respect to hemodynamic response and classification accuracy. To this end, subjects performed either mental arithmetic or imagined vocalization of the English alphabet as a baseline task with very low cognitive loading. The performances of two linear classifiers were compared; resulting in an advantage of shrinkage linear discriminant analysis (LDA). The classification accuracy of EC paradigm (75.6 ± 7.3%) was observed to be lower than that of EO paradigm (77.0 ± 9.2%), which was statistically insignificant (p = 0.5698). Subjects reported they felt it more comfortable (p = 0.057) and easier (p < 0.05) to perform the EC BCI tasks. The different task difficulty may become a cause of the slightly lower classification accuracy of EC data. From the analysis results, we could confirm the feasibility of NIRS-based EC BCIs, which can be a BCI option that may ultimately be of use for patients who cannot keep their eyes open consistently. PMID:27824089

  13. Intravitreal memantine retinal toxicity in rabbits.

    PubMed

    Moreno Páramo, D; Reyna Vielma, S; Rodríguez Reyes, A; Hernández Ayuso, I; Quiroz Mercado, H

    2016-02-01

    To histologically evaluate whether the intravitreal application of memantine produces retinal toxicity in rabbits. A cross-sectional design, experimental, descriptive study was performed on 16 eyes of 16 New Zealand rabbits of 3 kg, divided in 4 groups of 4 rabbits. A dose of 70 ng/ml of intravitreal memantine was administered in Group A, a dose of 150 ng/ml in Group B, a dose of 400 ng/ml in Group C, and Group D received 1 ml of balanced salt solution. The injected eye of half of each group was enucleated 15 days after the injection, and the rest within 30 days after injection. Following enucleation, each eye was placed in 10% formaldehyde. Histopathological analysis was performed on all enucleated eyes. The animals were treated according to the guidelines of the Association for Research on Vision and Ophthalmology (ARVO). Groups A, B and D did not show any histopathological changes after their enucleation at 15 and 30 days. Group C showed changes in the photoreceptor layer after enucleation at 15 and 30 days. In our study, it was observed that memantine concentrations at 70 ng/ml and 150 ng/ml are safe when administered intravitreally; however, doses of 400 ng/ml produced retinal structural changes. This research should continue to assess its clinical usefulness. Copyright © 2015 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  14. Polarimetric glucose sensing in an artificial eye anterior chamber

    NASA Astrophysics Data System (ADS)

    Malik, Bilal H.; Pirnstill, Casey W.; Coté, Gerard L.

    2012-03-01

    The application of optical polarimetry to glucose sensing in the anterior chamber of the eye has emerged as a potential technique to noninvasively ascertain blood glucose levels. One of the major limiting factors preventing the realization of such a device is the time varying corneal birefringence due to motion artifact in the eye. The varying birefringence confounds the optical activity of glucose, and thus, needs to be taken into account in order to successfully predict the glucose concentration in the aqueous humor of the eye. Our group has developed a multi-spectral optical polarimetric approach which can minimize the effect of corneal birefringence coupled with motion artifact by treating it as common mode noise to multiple wavelengths. Here, we present the application of a real-time closed-loop dual wavelength polarimeter to ex vivo glucose sensing in excised New Zealand White rabbits' corneas mounted on an artificial anterior chamber. Our PID control system can reach stability in less than 100 ms which is fast enough to overcome motion artifact due to heart beat and respiration. The system can predict the glucose concentration with a standard error of less than 26 mg/dL in the physiologic glucose range of 0 - 500 mg/dL. Our results indicate that dualwavelength polarimetry has the potential to noninvasively probe glucose through the anterior chamber of the eye.

  15. Viral infections of rabbits.

    PubMed

    Kerr, Peter J; Donnelly, Thomas M

    2013-05-01

    Viral diseases of rabbits have been used historically to study oncogenesis (e.g. rabbit fibroma virus, cottontail rabbit papillomavirus) and biologically to control feral rabbit populations (e.g. myxoma virus). However, clinicians seeing pet rabbits in North America infrequently encounter viral diseases although myxomatosis may be seen occasionally. The situation is different in Europe and Australia, where myxomatosis and rabbit hemorrhagic disease are endemic. Advances in epidemiology and virology have led to detection of other lapine viruses that are now recognized as agents of emerging infectious diseases. Rabbit caliciviruses, related to rabbit hemorrhagic disease, are generally avirulent, but lethal variants are being identified in Europe and North America. Enteric viruses including lapine rotavirus, rabbit enteric coronavirus and rabbit astrovirus are being acknowledged as contributors to the multifactorial enteritis complex of juvenile rabbits. Three avirulent leporid herpesviruses are found in domestic rabbits. A fourth highly pathogenic virus designated leporid herpesvirus 4 has been described in Canada and Alaska. This review considers viruses affecting rabbits by their clinical significance. Viruses of major and minor clinical significance are described, and viruses of laboratory significance are mentioned. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Anti-inflammatory and Antihistaminic Study of a Unani Eye Drop Formulation.

    PubMed

    Abdul, Latif; Abdul, Razique; Sukul, R R; Nazish, Siddiqui

    2010-01-01

    The Unani eye drop is an ophthalmic formulation prepared for its beneficial effects in the inflammatory and allergic conditions of the eyes. In the present study, the Unani eye drop formulation was prepared and investigated for its anti-inflammatory and antihistaminic activity, using in vivo and in vitro experimental models respectively. The Unani eye drop formulation exhibited significant anti-inflammatory activity in turpentine liniment-induced ocular inflammation in rabbits. The preparation also showed antihistaminic activity in isolated guinea-pig ileum. The anti-inflammatory and antihistaminic activity of eye drop may be due to presence of active ingredients in the formulation. Although there are many drugs in Unani repository which are mentioned in classical books or used in Unani clinical practice effectively in treatment of eye diseases by various Unani physicians. Inspite of the availability of vast literature, there is a dearth of commercial Unani ocular preparations. So, keeping this in mind, the eye drop formulation was prepared and its anti-inflammatory and antihistaminic activity was carried out in animal models. Thus, in view of the importance of alternative anti-inflammatory and antiallergic drugs, it becomes imperative to bring these indigenous drugs to the front foot and evaluate their activities.

  17. Anti-inflammatory and Antihistaminic Study of a Unani Eye Drop Formulation

    PubMed Central

    Abdul, Latif; Abdul, Razique; Sukul, R.R.; Nazish, Siddiqui

    2010-01-01

    The Unani eye drop is an ophthalmic formulation prepared for its beneficial effects in the inflammatory and allergic conditions of the eyes. In the present study, the Unani eye drop formulation was prepared and investigated for its anti-inflammatory and antihistaminic activity, using in vivo and in vitro experimental models respectively. The Unani eye drop formulation exhibited significant anti-inflammatory activity in turpentine liniment-induced ocular inflammation in rabbits. The preparation also showed antihistaminic activity in isolated guinea-pig ileum. The anti-inflammatory and antihistaminic activity of eye drop may be due to presence of active ingredients in the formulation. Although there are many drugs in Unani repository which are mentioned in classical books or used in Unani clinical practice effectively in treatment of eye diseases by various Unani physicians. Inspite of the availability of vast literature, there is a dearth of commercial Unani ocular preparations. So, keeping this in mind, the eye drop formulation was prepared and its anti-inflammatory and antihistaminic activity was carried out in animal models. Thus, in view of the importance of alternative anti-inflammatory and antiallergic drugs, it becomes imperative to bring these indigenous drugs to the front foot and evaluate their activities. PMID:23861612

  18. Pharmacokinetics of Intravitreally Injected Bevacizumab in Vitrectomized Eyes

    PubMed Central

    Ahn, Jeeyun; Kim, Hyuncheol; Park, Ji Hyun; Park, Sunyoung; Hwang, Duck Jin; Park, Kyu Hyung

    2013-01-01

    Abstract Purpose To compare the pharmacokinetics (PKs) of intravitreally injected bevacizumab in vitrectomized versus nonvitrectomized control rabbit eyes. Methods Twenty-five-gauge pars plana vitrectomy without lensectomy was performed in 17 right rabbit eyes (V) and 18 nonvitrectomized right rabbit eyes served as controls (C). After 1.25 mg/0.05 mL intravitreal bevacizumab (IVB) injections, eyes were enucleated at 1 h, 1, 2, 5, 14, and 30 days after the injection and immediately frozen at −80°C. Bevacizumab concentrations were determined after separation of frozen vitreous and aqueous humor (AH) compartments using indirect enzyme-linked immunosorbent assay. Bevacizumab concentration–time data were analyzed to obtain PK data. Results Vitreous clearance of IVB consisted of 2 phases, the first fast distribution and second slow elimination phase. Clearance of IVB was accelerated in V eyes only during the first phase and not in the second phase. The vitreous concentration percent ratios between V and C eyes were 94.7% (1 h), 70.5% (1 day), 89.2% (2 days), 94.2% (5 days), 99.2% (14 days), and 79.1% (30 days). Overall vitreous half-lives were 6.99 and 7.06 days for V and C eyes, respectively (1.6-h difference). Conclusion Overall IVB PKs in rabbit eyes after vitrectomy without lensectomy are not substantially different from nonvitrectomized control eyes. PMID:23735192

  19. Your Eyes

    MedlinePlus

    ... the eye and keeps it healthy. previous continue Light, Lens, Action These next parts are really cool, ... the eye. previous continue Rods and Cones Process Light The retina uses special cells called rods and ...

  20. Eye Anatomy

    MedlinePlus

    ... News About Us Donate In This Section Eye Anatomy en Español email Send this article to a ... You at Risk For Glaucoma? Childhood Glaucoma Eye Anatomy Five Common Glaucoma Tests Glaucoma Facts and Stats ...

  1. Eye emergencies

    MedlinePlus

    ... by common household products such as cleaning solutions, garden chemicals, solvents, or other types of chemicals. Fumes ... in the eye with a ball, such as indoor racket sports Images Eye First aid kit References ...

  2. Healthy Eyes

    MedlinePlus

    ... please turn Javascript on. Healthy Eyes Maintaining Your Vision Click for more information Taking good care of ... are qualified to perform eye exams. Aging and Vision Changes As you age, it is normal to ...

  3. Eye Emergencies

    MedlinePlus

    ... The Marfan Foundation Marfan & Related Disorders What is Marfan Syndrome? What are Related Disorders? What are the Signs? ... Emergencies Eye Emergencies Lung Emergencies Surgeries Eye Emergencies Marfan syndrome significantly increases your risk of retinal detachment, a ...

  4. Your Eyes

    MedlinePlus

    ... the eye and keeps it healthy. previous continue Light, Lens, Action These next parts are really cool, ... the eye. previous continue Rods and Cones Process Light The retina uses special cells called rods and ...

  5. Morphine-Stimulated Nitric Oxide Release in Rabbit Aqueous Humor

    PubMed Central

    Dortch-Carnes, Juanita; Russell, Karen

    2007-01-01

    Recent studies in our laboratory have demonstrated a role of nitric oxide (NO) in morphine-induced reduction of intraocular pressure (IOP) and pupil diameter (PD) in the New Zealand white (NZW) rabbit. The present study was designed to determine the effect of morphine on NO release in the aqueous humor of NZW rabbits, as this effect could be associated with morphine-mediated changes in aqueous humor dynamics and iris function. Dark adapted NZW rabbits were treated as follows: 1) treatment with morphine (10, 33 or 100 μg, 5 min); 2) treatment with morphine or endomorphin-1 for 5, 15 or 30 min; 3) pretreatment with naloxone (100 μg), L-NAME (125 μg) or reduced glutathione (GSH, 100 μg) for 30 minutes, followed by treatment with morphine (100 μg, 5 min). After the various treatment regimens, aqueous humor samples were obtained by paracenthesis and immediately assayed for nitrates and nitrites (an index of NO production), using a microplate assay kit. Morphine caused a dose-dependent increase in the levels of NO in aqueous humor after 5 min of treatment with each dose. Rabbits treated with endomorphin-1 (100 μg) had no significant change in NO levels in aqueous at any point in the time course. Aqueous samples from rabbits treated with morphine (100 μg) for 5 minutes increased from 29.84 ± 2.39 μM (control) to 183.94 ± 23.48 μM (treated). The increase in NO levels by morphine (100 μg, 5 min) was completely inhibited in the presence of naloxone (100 μg), L-NAME (125 μg) or GSH (100 μg). These results indicate that morphine-induced increase in NO production in aqueous humor is a transient response that is linked to activation of mu opioid receptors. Data obtained suggest that morphine-stimulated changes in ocular hydrodynamics and iris function are due, in part, to increased release of NO in aqueous humor. In addition, the sensitivity of the response to L-NAME and GSH suggests that morphine-induced release of nitric oxide into aqueous humor is mediated by

  6. Organophosphorus poisoning in two Rex rabbits.

    PubMed

    Jones, J M

    1984-01-01

    A case of organophosphorus (OP) poisoning in two Rex rabbits is described. Three animals were diagnosed as having dermatitis characterised by pruritus and alopecia due to infestation with Cheyletiella parasitivorax. Two of the animals were dipped in 2% malathion solution: one died within 15 hours post-dipping, the other was euthanased subsequent to the onset of convulsions. A procedure for the future dipping of rabbits is suggested, and a recommendation is made for a lower concentration of malathion to be used.

  7. Eye irritation testing of nanomaterials using the EpiOcular™ eye irritation test and the bovine corneal opacity and permeability assay.

    PubMed

    Kolle, Susanne N; Sauer, Ursula G; Moreno, Maria C Rey; Teubner, Wera; Wohlleben, Wendel; Landsiedel, Robert

    2016-04-15

    Assessment of eye irritation hazard has long been a core requirement in any chemical legislation. Nevertheless, publications focussing on the eye damaging potential of nanomaterials are scarce. Traditionally, eye irritation testing was performed using rabbits. The OECD Test Guideline 437 Bovine Corneal Opacity and Permeability (BCOP) test method allows determining severely irritating substances without animals, and the recently adopted OECD Test Guideline 492 Reconstructed human cornea-like epithelium test method allows identifying chemicals that neither induce eye irritation nor serious eye damage. For substances applicable to these tests, huge progress has been made in replacing animal testing. The in vitro eye irritation potential of 20 nanosized and 3 non-nanosized materials was investigated in a 2-tier EpiOcular™ Eye Irritation Test (EpiOcular™-EIT) and BCOP testing strategy including histopathology of the bovine corneas. Furthermore, applicability of the testing strategy for nanomaterials was assessed. Test materials encompassed OECD representative nanomaterials (metals (Ag), metal oxides (ZnO, TiO2, CeO2), amorphous SiO2 and MWCNTs), three organic pigments, quartz, and talc. None of the dry-powder nanomaterials elicited eye irritation in either the EpiOcular™-EIT or the BCOP assay. Likewise, an amorphous SiO2 nanomaterial that was supplied as suspension was tested negative in both assays. By contrast, in the EpiOcular™-EIT, the silver nanomaterial that was supplied as dispersion was tested positive, whereas its surfactant-containing dispersant was borderline to negative. In the BCOP assay, the silver nanomaterial elicited highly variable results and dark-brown patches remained on the corneal surface, whereas the results for its dispersant alone were borderline to positive, which was assessed as inconclusive due to high inter-assay variability. The present study points to the low eye irritation potential of a spectrum of nanomaterials, which is

  8. Variant rabbit hemorrhagic disease virus in young rabbits, Spain.

    PubMed

    Dalton, Kevin P; Nicieza, Inés; Balseiro, Ana; Muguerza, María A; Rosell, Joan M; Casais, Rosa; Álvarez, Ángel L; Parra, Francisco

    2012-12-01

    Outbreaks of rabbit hemorrhagic disease have occurred recently in young rabbits on farms on the Iberian Peninsula where rabbits were previously vaccinated. Investigation identified a rabbit hemorrhagic disease virus variant genetically related to apathogenic rabbit caliciviruses. Improved antivirus strategies are needed to slow the spread of this pathogen.

  9. Bupropion (Zyban, Wellbutrin) inhibits nicotine-induced viral reactivation in herpes simplex virus type 1 latent rabbits.

    PubMed

    Myles, Marvin E; Azcuy, Ann M; Nguyen, Ngoc T; Reisch, Eric R; Barker, Steven A; Thompson, Hilary W; Hill, James M

    2004-11-01

    We reported that nicotine applied via a transdermal patch (21 mg/day) induced viral reactivation and ocular shedding in herpes simplex virus type 1 (HSV-1) latent rabbits. One possible mechanism of action involves the release of catecholamines and other similar agents, triggering HSV reactivation. Bupropion (Zyban, Wellbutrin), a non-nicotine aid to smoking cessation, inhibits neuronal uptake of norepinephrine, serotonin, and dopamine. To determine whether bupropion inhibits HSV reactivation, rabbits latent with HSV-1 were grouped (at least 10 rabbits/group) and treated as follows: nicotine patch (transdermal delivery) and bupropion [Zyban sustained-release tablets (150 mg) twice a day (oral)], nicotine patch only, Zyban tablets only [twice a day (oral)], nicotine patch with oral placebo [twice a day (oral)], or no drug treatment. Eyes were swabbed for 22 consecutive days. The appearance of HSV-1 in the tear film was significantly less frequent in the bupropion-treated rabbits, in terms of positive rabbits/total rabbits, positive eyes/total eyes, and positive swabs/total swabs. Nicotine-treated rabbits had 78/440 (17.7%) positive/total swabs, and nicotine/placebo-treated rabbits had 149/792 (18.8%) positive/total swabs, whereas bupropion-treated rabbits had 23/440 (5.2%), and nicotine/bupropion-treated rabbits had 47/792 (5.9%) positive/total swabs. Thus, bupropion significantly reduces nicotine-induced HSV reactivation in latent rabbits.

  10. Rapid eye movement sleep disruption and sleep fragmentation are associated with increased orexin-A cerebrospinal-fluid levels in mild cognitive impairment due to Alzheimer's disease.

    PubMed

    Liguori, Claudio; Nuccetelli, Marzia; Izzi, Francesca; Sancesario, Giuseppe; Romigi, Andrea; Martorana, Alessandro; Amoroso, Chiara; Bernardini, Sergio; Marciani, Maria Grazia; Mercuri, Nicola Biagio; Placidi, Fabio

    2016-04-01

    The orexin system has been investigated in patients affected by mild cognitive impairment (MCI) due to Alzheimer's disease (AD) by measuring orexin-A concentrations in the cerebrospinal fluid (CSF), and correlated to subjective and objective sleep parameters, quantified by questionnaires and polysomnography, respectively. Twenty drug-naïve patients with MCI due to AD were studied and compared with a population of 26 age and/or sex matched controls, divided into subgroups on the basis of the Pittsburgh Sleep Quality Index (PSQI) score. Increased CSF-orexin levels were detected in patients with MCI due to AD in comparison with controls (p < 0.05). In particular, CSF-orexin concentrations were higher in MCI patients suffering from sleep complaints (PSQI ≥5, n = 10) compared with MCI patients with a regular sleep-wake cycle (PSQI <5, n = 10, p < 0.001) and compared with both control groups (with sleep complaints, PSQI ≥5, n = 11, p < 0.001; without sleep complaints, PSQI <5, n = 15, p < 0.001). Moreover, REM sleep was reduced in MCI patients compared with controls (p < 0.01), and had a negative correlation coupled with a reciprocal influence at the multiple regression analysis with CSF-orexin levels (R = -0.65; β = -8.90). REM sleep disruption and sleep fragmentation are related to higher CSF-orexin levels in patients with MCI due to AD, thus suggesting that the orexin system may be involved even in the earliest stages of AD, resulting in prolonged sleep latency, reduced sleep efficiency, and REM sleep impairment.

  11. Eye development.

    PubMed

    Baker, Nicholas E; Li, Ke; Quiquand, Manon; Ruggiero, Robert; Wang, Lan-Hsin

    2014-06-15

    The eye has been one of the most intensively studied organs in Drosophila. The wealth of knowledge about its development, as well as the reagents that have been developed, and the fact that the eye is dispensable for survival, also make the eye suitable for genetic interaction studies and genetic screens. This article provides a brief overview of the methods developed to image and probe eye development at multiple developmental stages, including live imaging, immunostaining of fixed tissues, in situ hybridizations, and scanning electron microscopy and color photography of adult eyes. Also summarized are genetic approaches that can be performed in the eye, including mosaic analysis and conditional mutation, gene misexpression and knockdown, and forward genetic and modifier screens.

  12. Common procedures in rabbits.

    PubMed

    Graham, Jennifer

    2006-05-01

    Rabbits are popular companion animals that present to veterinary clinics for routine and emergency care. Clinics equipped for treat-ing dogs and cats may be easily adapted to accommodate rabbits. This article reviews common procedures performed by the clinician specific to rabbits. Topics include handling and restraint, triage and patient assessment, sample collection, and supportive care techniques. Miscellaneous procedures, including anesthetic delivery, nasolacrimal duct flushing, and ear cleaning, are also discussed.

  13. INFECTIOUS PAPILLOMATOSIS OF RABBITS

    PubMed Central

    Shope, Richard E.; Hurst, E. Weston

    1933-01-01

    A papilloma has been observed in wild cottontail rabbits and has been found to be transmissible to both wild and domestic rabbits. The clinical and pathological pictures of the condition have been described. It has been found that the causative agent is readily filtrable through Berkefeld but not regularly through Seitz filters, that it stores well in glycerol, that it is still active after heating to 67°C. for 30 minutes, but not after heating to 70°C., and that it exhibits a marked tropism for cutaneous epithelium. The activities and properties of the papilloma-producing agent warrant its classification as a filtrable virus. Rabbits carrying experimentally produced papillomata are partially or completely immune to reinfection and, furthermore, their sera partially or completely neutralize the causative virus. The disease is transmissible in series through wild rabbits and virus of wild rabbit origin is readily transmissible to domestic rabbits, producing in this species papillomata identical in appearance with those found in wild rabbits. However, the condition is not transmissible in series through domestic rabbits. The possible significance of this observation has been discussed. The virus of infectious papillomatosis is not related immunologically to either the virus of infectious fibroma or to that of infectious myxoma of rabbits. PMID:19870219

  14. Diabetes eye exams

    MedlinePlus

    Diabetic retinopathy - eye exams; Diabetes - eye exams; Glaucoma - diabetic eye exam; Macular edema - diabetic eye exam ... if the doctor who takes care of your diabetes checks your eyes, you need an eye exam ...

  15. Effect of Monocular Deprivation on Rabbit Neural Retinal Cell Densities

    PubMed Central

    Mwachaka, Philip Maseghe; Saidi, Hassan; Odula, Paul Ochieng; Mandela, Pamela Idenya

    2015-01-01

    Purpose: To describe the effect of monocular deprivation on densities of neural retinal cells in rabbits. Methods: Thirty rabbits, comprised of 18 subject and 12 control animals, were included and monocular deprivation was achieved through unilateral lid suturing in all subject animals. The rabbits were observed for three weeks. At the end of each week, 6 experimental and 3 control animals were euthanized, their retinas was harvested and processed for light microscopy. Photomicrographs of the retina were taken and imported into FIJI software for analysis. Results: Neural retinal cell densities of deprived eyes were reduced along with increasing period of deprivation. The percentage of reductions were 60.9% (P < 0.001), 41.6% (P = 0.003), and 18.9% (P = 0.326) for ganglion, inner nuclear, and outer nuclear cells, respectively. In non-deprived eyes, cell densities in contrast were increased by 116% (P < 0.001), 52% (P < 0.001) and 59.6% (P < 0.001) in ganglion, inner nuclear, and outer nuclear cells, respectively. Conclusion: In this rabbit model, monocular deprivation resulted in activity-dependent changes in cell densities of the neural retina in favour of the non-deprived eye along with reduced cell densities in the deprived eye. PMID:26425316

  16. Effect of Monocular Deprivation on Rabbit Neural Retinal Cell Densities.

    PubMed

    Mwachaka, Philip Maseghe; Saidi, Hassan; Odula, Paul Ochieng; Mandela, Pamela Idenya

    2015-01-01

    To describe the effect of monocular deprivation on densities of neural retinal cells in rabbits. Thirty rabbits, comprised of 18 subject and 12 control animals, were included and monocular deprivation was achieved through unilateral lid suturing in all subject animals. The rabbits were observed for three weeks. At the end of each week, 6 experimental and 3 control animals were euthanized, their retinas was harvested and processed for light microscopy. Photomicrographs of the retina were taken and imported into FIJI software for analysis. Neural retinal cell densities of deprived eyes were reduced along with increasing period of deprivation. The percentage of reductions were 60.9% (P < 0.001), 41.6% (P = 0.003), and 18.9% (P = 0.326) for ganglion, inner nuclear, and outer nuclear cells, respectively. In non-deprived eyes, cell densities in contrast were increased by 116% (P < 0.001), 52% (P < 0.001) and 59.6% (P < 0.001) in ganglion, inner nuclear, and outer nuclear cells, respectively. In this rabbit model, monocular deprivation resulted in activity-dependent changes in cell densities of the neural retina in favour of the non-deprived eye along with reduced cell densities in the deprived eye.

  17. Ocular Safety and Pharmacokinetics Study of FK506 Suspension Eye Drops After Corneal Transplantation

    PubMed Central

    Yuan, Jin; Zhai, Jia-jie; Huang, Xi; Zhou, Shi-you

    2012-01-01

    Abstract Purpose The aim of this study was to investigate the sensitization, pharmacokinetics, and absorption of FK506 after corneal transplantation. Methods New Zealand albino rabbits were divided into normal and corneal transplantation groups. Each group was divided into 5 subgroups—saline, blank matrix, high-dose, medium-dose, and low-dose, respectively. There were 10 rabbits in each subgroup. One drop (25 μL) of FK506 was administered topically to both eyes of the rabbits 4 times daily for 30 days. Thirty days later, 5 rabbits of each subgroup were sacrificed after the administration of the last dose. Both eyes were enucleated; the left eye was used for pathologic examination and the right eye for the determination of FK506 distribution. The other 5 rabbits in each subgroup were sacrificed 14 days after the former 5 rabbits were sacrificed, and their eyes were enucleated for pathologic examination and tissue distribution determination as the former 5 rabbits in each subgroup (the second batch). Results Fluorescein staining and local ocular reaction provided evidence that there were no significant differences between control and FK506-instilled eyes in the rabbit model at any of the tested doses. Histologic examination revealed no ocular abnormality in the rabbits instilled with any doses of FK506 eyedrop. The peak serum concentration (Cmax) of systemic absorption ranged from 4.31±0.79 ng/mL to 14.89±6.85 ng/mL. Conclusion Our study suggests that up to 0.1% FK506 administered 4 times a day (q.i.d.) topically is safe for the rabbit eye. However, further safety studies are required in view of systemic adverse effects. PMID:22136074

  18. Ocular safety and pharmacokinetics study of FK506 suspension eye drops after corneal transplantation.

    PubMed

    Yuan, Jin; Zhai, Jia-jie; Huang, Xi; Zhou, Shi-you; Chen, Jia-qi

    2012-04-01

    The aim of this study was to investigate the sensitization, pharmacokinetics, and absorption of FK506 after corneal transplantation. New Zealand albino rabbits were divided into normal and corneal transplantation groups. Each group was divided into 5 subgroups--saline, blank matrix, high-dose, medium-dose, and low-dose, respectively. There were 10 rabbits in each subgroup. One drop (25 μL) of FK506 was administered topically to both eyes of the rabbits 4 times daily for 30 days. Thirty days later, 5 rabbits of each subgroup were sacrificed after the administration of the last dose. Both eyes were enucleated; the left eye was used for pathologic examination and the right eye for the determination of FK506 distribution. The other 5 rabbits in each subgroup were sacrificed 14 days after the former 5 rabbits were sacrificed, and their eyes were enucleated for pathologic examination and tissue distribution determination as the former 5 rabbits in each subgroup (the second batch). Fluorescein staining and local ocular reaction provided evidence that there were no significant differences between control and FK506-instilled eyes in the rabbit model at any of the tested doses. Histologic examination revealed no ocular abnormality in the rabbits instilled with any doses of FK506 eyedrop. The peak serum concentration (C(max)) of systemic absorption ranged from 4.31±0.79 ng/mL to 14.89±6.85 ng/mL. Our study suggests that up to 0.1% FK506 administered 4 times a day (q.i.d.) topically is safe for the rabbit eye. However, further safety studies are required in view of systemic adverse effects.

  19. Optimization of Cultured Human Corneal Endothelial Cell Sheet Transplantation and Post-Operative Sheet Evaluation in a Rabbit Model.

    PubMed

    Yamaguchi, Masahiro; Shima, Nobuyuki; Kimoto, Miwa; Ebihara, Nobuyuki; Murakami, Akira; Yamagami, Satoru

    2016-09-01

    To optimize cultured human corneal endothelial cell (cHCEC) sheet transplantation technique for maintenance of cHCEC viability. cHCEC sheets cultured on a collagen scaffold were covered with or without Viscoat® and exposed to humidified air in the incubator. cHCEC sheets with or without Viscoat® were transplanted into cadaveric porcine eyes by the DSAEK technique with full air tamponade and incubated for various time periods. Then cell viability was determined by using the live/dead assay kit. cHCEC sheets with Viscoat® were transplanted into rabbit eyes and the sheets were histologically evaluated before and 14 days after transplantation. A collagen scaffold and Viscoat® were effective for protecting cHCEC from damage due to air exposure in vitro. All cells died after 18 hours of air exposure in porcine eyes in Viscoat® untreated control. In contrast, Viscoat® treatment sustained full cell viability following 2 hours and could maintain approximately 80% viability after 18 hours. In a rabbit model, transplanted cHCEC sheet with Viscoat® maintained cell density at 2803 ± 229 mm(2) (18% cell loss) and expression of N-cadherin, zonula occludens-1, and actin-filament localized to cell boundary as similar as donor HCEC. Viscoat® can contribute to cHCEC protection from damage caused by exposure to air.

  20. Pharmacokinetics of intravitreal bevacizumab (Avastin®) in rabbits

    PubMed Central

    Sinapis, Christos I; Routsias, John G; Sinapis, Angelos I; Sinapis, Dimitrios I; Agrogiannis, George D; Pantopoulou, Alkistis; Theocharis, Stamatis E; Baltatzis, Stefanos; Patsouris, Efstratios; Perrea, Despoina

    2011-01-01

    Purpose: To describe the pharmacokinetics of intravitreal bevacizumab (Avastin®) in rabbits. Methods: The right eye of 20 rabbits was injected intravitreally with 1.25 mg/0.05 mL bevacizumab. Both eyes of four rabbits each time were enucleated at days 1, 3, 8, 15, and 29. Bevacizumab concentrations were measured in serum, aqueous humor, and vitreous. Results: Maximum vitreous (406.25 μg/mL) and aqueous humor (5.83 μg/mL) concentrations of bevacizumab in the right eye were measured at day 1. Serum bevacizumab concentration peaked at day 8 (0.413 μg/mL) and declined to 0.032 μg/mL at 4 weeks. Half-life values in right vitreous, right aqueous humor, and serum were 6.61, 6.51, and 5.87 days, respectively. Concentration of bevacizumab in the vitreous of the noninjected eye peaked at day 8 (0.335 ng/mL) and declined to 0.218 ng/mL at 4 weeks. In the aqueous humor of the noninjected eye, maximum concentration of bevacizumab was achieved at day 8 (1.6125 ng/mL) and declined (to 0.11 ng/mL) at 4 weeks. Conclusion: The vitreous half-life of 1.25 mg/0.05 mL intravitreal bevacizumab was 6.61 days in this rabbit model. Maximum concentrations of bevacizumab were reached at day 1 in both vitreous and aqueous humor of the right eye and at day 8 in the serum. Very low concentrations of bevacizumab were measured in the fellow noninjected eye. PMID:21629577

  1. Eye Health

    PubMed Central

    Connell, A. M. S.

    1988-01-01

    The status of eye care in the Caribbean is discussed. Methods of primary eye care providers at all levels from primary to tertiary in the region are presented against a background of the major causes of blindness, cataract, glaucoma, and diabetic retinopathy. Epidemiological surveys examining prevalence, risk factors, and intervention programs are being undertaken. PMID:3404562

  2. Eyes - bulging

    MedlinePlus

    ... emotional support is important. When to Contact a Medical Professional Call your health care provider if: You have bulging eyes and the cause has not yet been diagnosed. Bulging eyes are accompanied by other symptoms. ... The provider will ask about your medical history and do a physical exam. Some questions ...

  3. [Eye and lymph drainage].

    PubMed

    Grüntzig, J; Schicha, H; Huth, F

    1979-06-01

    Up to now lymphatics in the eye could not be pointed out. An ocular lymph drainage is denied. Földi succeeded in producing experimentally the syndrome of "lymphostatic encephalopathy and ophthalmopathy" by operative blockade of the cervical lymphatics in animals. In the first part of the present paper a historical view considering the subject "Eye and lymphatic system" is given. In the second part it is entered into the particulars of own experimental studies. As to our own investigations, rabbits have been injected 99mTc-sulfur-colloid, 99mTc-microcolloid, 99mTc-Albumin and 198Au-colloid into the retrobulbar space, anterior chamber, vitreous body and subconjuctival space of one eye. Measurements of the activity's distribution have been made in vivo with an Anger type camera (pho-Gamma-IV Hp, Searle Nuclear Chicago) and in vitro after section with a sodium iodine crystal well counter (Clinimat-200, Picker). In some animals the investigation has been combined with a bilateral dissection of the cervical lymph nodes. After injection in the retrobulbar space a significant concentration of the activity could be observed for the most part in the equilateral Lymphonodulus cervicalis profundus. By the cervical lymph blockade the removal of lymphoctopic substances from the retrobulbar space was largely inhibited. After injection in the anterior chamber a significant concentration could be observed for the most part in the equilateral Lymphonodulus cervicalis superficialis. After intravitreal injection a drainage to the bilateral deep cervical lymph nodes could be observed. After injection into the subconjunctival space a significant accumulation of activity could be registered in the equilateral Lymphonoduli mandibulares and cervicales superficiales. The data substantiate a segmental lymph drainage from the eye: vitreous body and retrobulbar space for the most part into the Lymphonoduli cervicales profundi, anterior chamber and subconjunctival space for the most part into

  4. Health survey of 167 pet rabbits (Oryctolagus cuniculus) in Finland.

    PubMed

    Mäkitaipale, J; Harcourt-Brown, F M; Laitinen-Vapaavuori, O

    2015-10-24

    Only a limited amount of information is available about health status of pet rabbits. The aim of this study was to obtain data about the health status of pet rabbits considered healthy by the owners in Finland. Physical examination and lateral abdominal and lateral skull radiography were performed on 167 pet rabbits of which 118 (70.7 per cent) had abnormal findings in at least one examination. The most common findings were acquired dental disease (n=67, 40.1 per cent), vertebral column deformities and degenerative lesions (n=52, 31.1 per cent), skin disorders (n=28, 16.8 per cent) and eye disorders (n=12, 7.2 per cent). Vertebral column angulating deformities were significantly more common in dwarf lop rabbits (P≤0.001). The prevalence of health disorders was significantly higher in rabbits over three years of age of which 51 (82.3 per cent) had findings in at least one examination (P<0.05). Rabbits as prey animals hide their illness, which cause difficulties to owners to recognise health problems. Because of the high prevalence of clinical and radiological findings in apparently healthy pet rabbits, regular physical examinations are advised, especially for animals over three years old. British Veterinary Association.

  5. Autoantibody Production in Rabbits

    PubMed Central

    Asherson, G. L.; Rose, M. Elaine

    1963-01-01

    The finding that the serum of apparently healthy rabbits fixed complement with rabbit liver and kidney has been confirmed. Experimental infection of rabbits with Eimeria stiedae, the cause of hepatic coccidiosis, led to a rise in the titre of serum complement-fixing factors. The rise was statistically significant 14, 21 and 28 days after infection. The factors were regarded as antibodies because they behaved as macroglobulins on diethylaminoethyl—cellulose chromatography and sucrose gradient centrifugation, and as autoantibodies because they fixed complement with the kidney of the rabbits in which they occurred. The antibody reacted with widely distributed antigen(s) with high activity in brain and low activity in skeletal muscle. The possibility that coccidial infection may be responsible for the natural autoantibody of rabbits is discussed. PMID:13965167

  6. Biocompatibility of poly(ethylene glycol) and poly(acrylic acid) interpenetrating network hydrogel by intrastromal implantation in rabbit cornea.

    PubMed

    Zheng, Luo Luo; Vanchinathan, Vijay; Dalal, Roopa; Noolandi, Jaan; Waters, Dale J; Hartmann, Laura; Cochran, Jennifer R; Frank, Curtis W; Yu, Charles Q; Ta, Christopher N

    2015-10-01

    We evaluated the biocompatibility of a poly(ethylene glycol) and poly(acrylic acid) (PEG/PAA) interpenetrating network hydrogel designed for artificial cornea in a rabbit model. PEG/PAA hydrogel measuring 6 mm in diameter was implanted in the corneal stroma of twelve rabbits. Stromal flaps were created with a microkeratome. Randomly, six rabbits were assigned to bear the implant for 2 months, two rabbits for 6 months, two rabbits for 9 months, one rabbit for 12 months, and one rabbit for 16 months. Rabbits were evaluated monthly. After the assigned period, eyes were enucleated, and corneas were processed for histology and immunohistochemistry. There were clear corneas in three of six rabbits that had implantation of hydrogel for 2 months. In the six rabbits with implant for 6 months or longer, the corneas remained clear in four. There was a high rate of epithelial defect and corneal thinning in these six rabbits. One planned 9-month rabbit developed extrusion of implant at 4 months. The cornea remained clear in the 16-month rabbit but histology revealed epithelial in-growth. Intrastromal implantation of PEG/PAA resulted in a high rate of long-term complications.

  7. Biocompatibility of poly(ethylene glycol) and poly(acrylic acid) interpenetrating network hydrogel by intrastromal implantation in rabbit cornea

    PubMed Central

    Zheng, Luo Luo; Vanchinathan, Vijay; Dalal, Roopa; Noolandi, Jaan; Waters, Dale J.; Hartmann, Laura; Cochran, Jennifer R.; Frank, Curtis W.; Yu, Charles Q.; Ta, Christopher N.

    2015-01-01

    We evaluated the biocompatibility of a poly(ethylene glycol) and poly(acrylic acid) (PEG/PAA) interpenetrating network hydrogel designed for artificial cornea in a rabbit model. PEG/PAA hydrogel measuring 6 mm in diameter was implanted in the corneal stroma of twelve rabbits. Stromal flaps were created with a microkeratome. Randomly, six rabbits were assigned to bear the implant for 2 months, two rabbits for 6 months, two rabbits for 9 months, one rabbit for 12 months, and one rabbit for 16 months. Rabbits were evaluated monthly. After the assigned period, eyes were enucleated, and corneas were processed for histology and immunohistochemistry. There were clear corneas in three of six rabbits that had implantation of hydrogel for 2 months. In the six rabbits with implant for 6 months or longer, the corneas remained clear in four. There was a high rate of epithelial defect and corneal thinning in these six rabbits. One planned 9-month rabbit developed extrusion of implant at 4 months. The cornea remained clear in the 16-month rabbit but histology revealed epithelial in-growth. Intrastromal implantation of PEG/PAA resulted in a high rate of long-term complications. PMID:25778285

  8. Histological and confocal changes in rabbit cornea produced by an intrastromal inlay made of hexafocon A.

    PubMed

    Salamatrad, Ahmad; Jabbarvand, Mahmoud; Hashemian, Hesam; Khodaparast, Mehdi; Askarizadeh, Farshad

    2015-01-01

    The aim of this study was to evaluate biocompatibility of a newly proposed intrastromal inlay in rabbit corneas. Eighteen eyes of 9 New Zealand rabbits were included in this prospective study. An intrastromal pocket was created in both eyes using Melles instruments. Annular intracorneal inlays made of hexafocon A were implanted randomly into the stromal pocket of one eye of each rabbit. Confocal microscopy was performed at each visit during 6-month follow-up. After 6 months, the rabbits were killed and corneal tissues of both eyes were sent for light microscopic studies. Mild stromal edema was present during the first few days and disappeared afterward with mild haze around the tunnel site in all cases. Deposits around the lamellar channel developed in 3 implanted eyes and in none of the pocket-only eyes. No neovascularization or epithelial downgrowth was present at the incision site in any case. All inlays remained centered and optically clear. In confocal imaging, we observed no significant difference in keratocyte cell density and inflammatory cells between the control pocket-only group and inlay group. In pathological evaluation, there was no difference in the average epithelial thickness between both groups. Descemet membrane and endothelium appeared normal in both groups. This study revealed safety and biocompatibility of hexafocon A as an intracorneal inlay in rabbits.

  9. Formulation of indomethacin eye drops via complexation with cyclodextrins.

    PubMed

    Halim Mohamed, Maaly A; Mahmoud, Azza A

    2011-03-01

    Topically administered indomethacin is used in the management and prevention of ocular inflammation and cystoid macular edema related to cataract surgery and in the maintenance of mydriasis during cataract surgery. Pharmaceutically, the main obstacle in formulating indomethacin as eye drops is its low solubility and aqueous instability. Inclusion complexation of indomethacin with cyclodextrins (CDs) was our interest in this research to obtain stable and effective aqueous indomethacin eye drops. The influence of β-CD, hydroxypropyl-β-CD (HP-β-CD), and sulfobutyl ether-β-CD (SBE-β-CD) on indomethacin solubility was investigated. Indomethacin-HP-β-CD complex was prepared and characterized by infrared spectroscopy, differential scanning calorimetry, and X-ray diffractometry and was subjected to in vitro release and stability studies. The anti-inflammatory effect of formulated indomethacin-HP-β-CD eye drops on chemically burned albino rabbit eyes was compared to those of Indocollyre(®) and Voltaren(®) eye drops. HP-β-CD was found to have a high solubilizing effect towards indomethacin and was thus selected for its formulation. Formulated indomethacin-HP-β-CD eye drops exhibited delayed release and high drug stability compared to the drug solution. Draize rabbit eye irritation test and histological examination on albino rabbit eyes treated with indomethacin-HP-β-CD eye drops revealed that these eye drops were non-irritant. The anti-inflammatory studies indicated that formulating indomethacin eye drops via complexation with HP-β-CD significantly improves the therapeutic efficacy of the indomethacin compared to the investigated eye drops. An aqueous ocular delivery system for the poor water soluble anti-inflammatory indomethacin was prepared using HP-β-CD as a complexing agent. Besides a sufficient solubility for the drug, many factors were studied in the development of this system, such as stability and safety. In addition, indomethacin-HP-β-CD eye drops

  10. Comparison of Cytotoxic Effects on Rabbit Corneal Endothelium between Preservative-free and Preservative-containing Dorzolamide/timolol

    PubMed Central

    Kwon, Junki; Heo, Jeong Hwa; Kim, Hyo Myung

    2015-01-01

    Purpose To evaluate and compare the toxic effects of eyedrops containing a fixed combination of 2.0% dorzolamide and 0.5% maleate timolol with or without preservatives on rabbit corneal endothelium. Methods This study was performed with 22 eyes of New Zealand white rabbits. Dorzolamide/timolol eyedrops with preservative (Cosopt group) or without preservative (Cosopt-S group) were diluted with a balanced salt solution at a 1 : 1 ratio. We injected 0.1 mL of diluted Cosopt into the anterior chamber of left eyes and an equal volume of diluted Cosopt-S into the anterior chamber of right eyes. Corneal thickness, corneal haze, and conjunctival injection were measured before and 24 hours after treatment. Endothelial damage was compared between both eyes by vital staining (alizarin red/trypan blue staining), live/dead cell assay, TUNEL assay, and scanning electron microscopy. Results Corneal endothelial damage was severe in the Cosopt group. Cosopt-treated eyes exhibited remarkable corneal edema and prominent apoptosis of endothelial cells. In addition, the live/dead cell assay revealed many dead cells in the endothelium, and scanning electron microscopy analysis showed that corneal endothelial cells exhibited a partial loss of microvilli on the surface as well as extensive destruction of intercellular junctions. However, in the Cosopt-S group, corneal edema was mild and the damage to the corneal endothelium was minimal. Conclusions The main cause of corneal endothelial toxicity was due to the preservative in the dorzolamide/timolol fixed combination eyedrops, and not the active ingredient. Thus, it appears to be safer to use preservative-free eyedrops during the early postoperative period. PMID:26457041

  11. Rapid Eye Movement Sleep Deprivation Associated Increase in Na-K ATPase Activity in the Rat Brain is Due to Noradrenaline Induced α1-Adrenoceptor Mediated Increased α-Subunit of the Enzyme.

    PubMed

    Amar, Megha; Mallick, Birendra Nath

    2015-08-01

    Rapid eye movement sleep (REMS) modulates Na-K ATPase activity and maintains brain excitability. REMS deprivation (REMSD)-associated increased Na-K ATPase activity is mediated by noradrenaline (NA) acting on α1-adrenoceptor (AR) in the brain. It was shown that NA-induced increased Na-K ATPase activity was due to allosteric modulation as well as increased turnover of the enzyme. Although the former has been studied in detail, our understanding on the latter was lacking, which we have studied. Male Wistar rats were REMS deprived for 4-days by classical flower-pot method; suitable control experiments were conducted. In another set, α1-AR antagonist prazosin (PRZ) was i.p. injected 48 h REMSD onward. At the end of experiments rats were sacrificed by cervical dislocation and brains were removed. Synaptosomes prepared from the brains were used to estimate Na-K ATPase activity as well as protein expressions of different isoforms of the enzyme subunits using western blot. REMSD significantly increased synaptosomal Na-K ATPase activity and that was due to differential increase in the expressions of α1-, α2- and α3-isoforms, but not that of β1- and β2-isoforms. PRZ reduced the REMSD-induced increased Na-K ATPase activity and protein expressions. We also observed that the increased Na-K ATPase subunit expression was not due to enhanced mRNA synthesis, which suggests the possibility of post-transcriptional regulation. Thus, the findings suggest that REMSD-associated increased Na-K ATPase activity is due to elevated level of α-subunit of the enzyme and that is induced by NA acting on α1-AR mediated mRNA-stabilization.

  12. Teary eyes due to 21 pence?

    PubMed Central

    Wong, Phui Yee; Charn, Tze Choong; Ismail, Andre; Tatla, Taran

    2015-01-01

    A woman in her late 70s with chronic bilateral epiphora under ophthalmology review was referred to our department for dacryocystorhinostomy after punctoplasty and detection of nasolacrimal duct obstruction. A CT scan of the paranasal sinuses for preoperative planning revealed complete opacification of the right maxillary, anterior ethmoid, frontal and sphenoid sinuses, left septal deviation and an incidental finding of foreign bodies in the right anterior nasal airspace. She proceeded with functional endoscopic sinus surgery (FESS) and removal of foreign bodies. To our surprise, a partially eroded 20 pence and 1 penny coin were found and removed from her right nasal airway. There was no history given about foreign bodies in her nose. Her symptoms improved postoperatively. PMID:25687704

  13. Identification of cornifelin and early growth response-1 gene as novel biomarkers for in vitro eye irritation using a 3D reconstructed human cornea model MCTT HCE™.

    PubMed

    Choi, Seunghye; Lee, Miri; Lee, Su-Hyon; Jung, Haeng-Sun; Kim, Seol-Yeong; Chung, Tae-Young; Choe, Tae-boo; Chun, Young-Jin; Lim, Kyung-Min

    2015-09-01

    Evaluation of the eye irritation is essential in the development of new cosmetic products. Draize rabbit eye irritation test has been widely used in which chemicals are directly applied to rabbit eye, and the symptoms and signs of eyes are scored. However, due to the invasive procedure, it causes substantial pain and discomfort to animals. Recently, we reported in vitro eye irritation test method using a 3D human corneal epithelial model (MCTT HCE™) which is reconstructed from remaining human tissues after a corneal transplantation. This model exhibited an excellent predictive capacity for 25 reference chemicals (sensitivity 100%, specificity 77% and accuracy 88% vs. GHS). To improve the test performance, we explored new biomarkers for the eye irritation through transcriptomic approach. Three surfactants were selected as model eye irritants that include sodium lauryl sulfate, benzalkonium chloride and triton X-100. After test chemicals were treated, we investigated differentially expressed genes through a whole-gene microarray (Affymetrix GeneChip(®) Human Gene 2.0 ST Array, 48,000 probes). As a result, we identified that mRNAs of cornifelin (CNFN), a constituent of the insoluble cornified cell envelope of stratified squamous epithelia, and early growth response-1 (EGR1), a nuclear transcriptional regulator, were significantly up-regulated by all three irritants. Up-regulation of CNFN and EGR1 was further confirmed by Q-RT-PCR, and immunohistochemistry revealed increased level of CNFN in irritant-treated tissues, supporting the relevance of CNFN and EGR1 as new biomarkers for eye irritation.

  14. Black Eye

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  15. Eye Symptoms

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  16. Eye Infections

    MedlinePlus

    ... become red, he probably has a condition called conjunctivitis . Also known as pinkeye, this inflammation, which can be painful and itchy, ... bacteria, antibiotic eye drops are the usual treatment. Conjunctivitis caused by viruses should not be treated with ...

  17. Nerve growth factor antibody stimulates reactivation of ocular herpes simplex virus type 1 in latently infected rabbits.

    PubMed

    Hill, J M; Garza, H H; Helmy, M F; Cook, S D; Osborne, P A; Johnson, E M; Thompson, H W; Green, L C; O'Callaghan, R J; Gebhardt, B M

    1997-06-01

    Anti-nerve growth factor (anti-NGF) antibody has been shown to induce reactivation of latent herpes simplex virus type 1 (HSV-1) in vitro. We found that systemically administered anti-NGF induces ocular shedding of HSV-1 in vivo in rabbits harboring latent virus. Rabbits in which HSV-1 latency had been established were given intravenous injections of goat anti-NGF serum daily for 10 days beginning 42 days after primary viral infection. Tears were assayed for virus for 12 days beginning on the day of the first injection. All eight rabbits given high titer anti-NGF had infectious virus in their tears at least once during the 12-day period. Fifteen of 16 eyes were positive and the average duration of viral shedding for these eyes was 4.0 days. Latently infected rabbits receiving daily injections of nonimmune goat serum or saline for 10 consecutive days were controls. Only six of the 16 (38%) eyes from rabbits receiving nonimmune goat serum shed virus. Only one of 12 eyes from untreated rabbits shed virus. Sera from control rabbits had no detectable anti-NGF activity; titers in anti-NGF-treated rabbits ranged between 1:1000 and 1:10,000. NGF deprivation may act as a neuronal stressor and may share a common second messenger pathway with heat- or cold-stress induced reactivation of latent HSV-1.

  18. Hepatitis E Virus in Farmed Rabbits, Wild Rabbits and Petting Farm Rabbits in the Netherlands.

    PubMed

    Burt, Sara A; Veltman, Jorg; Hakze-van der Honing, Renate; Schmitt, Heike; van der Poel, Wim H M

    2016-09-01

    Rabbits have been suggested as a zoonotic source of Hepatitis E virus. Phylogenetic analysis of HEV isolates from farmed, wild and pet rabbits in the Netherlands (23, 0, and 60 % respectively) showed them to be grouped amongst published rabbit HEV sequences and distinct from most human isolates. Dutch rabbits are unlikely to be a zoonotic source.

  19. SERUM SICKNESS IN RABBITS

    PubMed Central

    Fleisher, Mover S.; Jones, Lloyd

    1931-01-01

    1. The injection of a single large dose of normal horse serum into rabbits results in the appearance 3 to 8 days later of erythematous and edematous reactions on the ears in 68.9 per cent of the animals. 2. The injections may be given by any of several routes and reactions appear when the site of injection is definitely distant from the ears. 3. Injections of various antisera into rabbits cause the appearance of similar reactions. 4. These reactions can be considered as manifestations of serum sickness in rabbits. PMID:19869943

  20. Rabbit orthopedic surgery.

    PubMed

    Rich, Gregory A

    2002-01-01

    Orthopedic surgery in rabbits poses several unique parameters for the veterinary surgeon. It is imperative for the veterinarian to be knowledgeable about the anatomic features of the surgical repair site and to become familiar with a rabbit's pain and discomfort often associated with orthopedic injuries. Handling the perioperative and postoperative pain and potential GI disturbances are crucial for a successful outcome of the surgical case. This article is designed to help the veterinary surgeon prepare for the orthopedic surgical procedure and the peripheral physiologic needs of the rabbit from presentation through recovery.

  1. Incidence of Spontaneous Ocular Lesions in Laboratory Rabbits

    PubMed Central

    Holve, Dana L; Mundwiler, Karen E; Pritt, Stacy L

    2011-01-01

    Laboratory rabbits are commonly used for ocular drug and device studies. The purpose of this study was to determine the incidence of spontaneous ocular lesions in laboratory rabbits with respect to sex, breed, and supplier. We retrospectively evaluated ophthalmic examination records of rabbits screened between April 2008 and April 2010. These 1840 records represented 572 black Dutch belted (DB), 1022 New Zealand white (NZW), and 246 NZW × New Zealand red F1 crosses (WRF1). Rabbits were between 6 and 16 wk of age and had been received from 5 suppliers. Ocular structures evaluated were the cornea, lens, iris and vitreous with respect to sex, breed and supplier. A total of 177 rabbits (9.6%) and 233 eyes (6.3%) were effected. Of total rabbits, 15.3% males and 7.3% females were affected. The most common structure affected was the cornea in 5.7% of rabbits, (DB 11.7%, NZW 3.0%, and NZR 3.3%). The lens at 3.6% was second most common (DB 2.1%, NZW 4.6%, and NZR 3.3%). Both iris (0.2%) and vitreous (0.3%) were not significantly affected. Significant sex-breeder-supplier combinations were: cornea DB supplier D, supplier D females, supplier D males, DB males and NZR females; and lens: NZW females; and at least one affected ocular structure: NZW supplier D, supplier D females, DB males, NZW females, and NZR females. Breed, sex, and supplier were significant variables of ocular lesions in laboratory rabbits. Investigators should consider each of these variables when choosing rabbits for ocular studies. PMID:22330351

  2. Incidence of spontaneous ocular lesions in laboratory rabbits.

    PubMed

    Holve, Dana L; Mundwiler, Karen E; Pritt, Stacy L

    2011-10-01

    Laboratory rabbits are commonly used for ocular drug and device studies. The purpose of this study was to determine the incidence of spontaneous ocular lesions in laboratory rabbits with respect to sex, breed, and supplier. We retrospectively evaluated ophthalmic examination records of rabbits screened between April 2008 and April 2010. These 1840 records represented 572 black Dutch belted (DB), 1022 New Zealand white (NZW), and 246 NZW × New Zealand red F(1) crosses (WRF1). Rabbits were between 6 and 16 wk of age and had been received from 5 suppliers. Ocular structures evaluated were the cornea, lens, iris and vitreous with respect to sex, breed and supplier. A total of 177 rabbits (9.6%) and 233 eyes (6.3%) were effected. Of total rabbits, 15.3% males and 7.3% females were affected. The most common structure affected was the cornea in 5.7% of rabbits, (DB 11.7%, NZW 3.0%, and NZR 3.3%). The lens at 3.6% was second most common (DB 2.1%, NZW 4.6%, and NZR 3.3%). Both iris (0.2%) and vitreous (0.3%) were not significantly affected. Significant sex-breeder-supplier combinations were: cornea DB supplier D, supplier D females, supplier D males, DB males and NZR females; and lens: NZW females; and at least one affected ocular structure: NZW supplier D, supplier D females, DB males, NZW females, and NZR females. Breed, sex, and supplier were significant variables of ocular lesions in laboratory rabbits. Investigators should consider each of these variables when choosing rabbits for ocular studies.

  3. What Causes Eye Pain?

    PubMed

    Belmonte, Carlos; Acosta, M Carmen; Merayo-Lloves, Jesus; Gallar, Juana

    Eye pain is an unpleasant sensory and emotional experience including sensory-discriminative, emotional, cognitive, and behavioral components and supported by distinct, interconnected peripheral and central nervous system elements. Normal or physiological pain results of the stimulation by noxious stimuli of sensory axons of trigeminal ganglion (TG) neurons innervating the eye. These are functionally heterogeneous. Mechano-nociceptors are only excited by noxious mechanical forces. Polymodal nociceptors also respond to heat, exogenous irritants, and endogenous inflammatory mediators, whereas cold thermoreceptors detect moderate temperature changes. Their distinct sensitivity to stimulating forces is determined by the expression of specific classes of ion channels: Piezo2 for mechanical forces, TRPV1 and TRPA1 for heat and chemical agents, and TRPM8 for cold. Pricking pain is evoked by mechano-nociceptors, while polymodal nociceptors are responsible of burning and stinging eye pain; sensations of dryness appear to be mainly evoked by cold thermoreceptors. Mediators released by local inflammation, increase the excitability of eye polymodal nociceptors causing their sensitization and the augmented pain sensations. During chronic inflammation, additional, long-lasting changes in the expression and function of stimulus-transducing and voltage-sensitive ion channels develop, thereby altering polymodal terminal's excitability and evoking chronic inflammatory pain. When trauma, infections, or metabolic processes directly damage eye nerve terminals, these display aberrant impulse firing due to an abnormal expression of transducing and excitability-modulating ion channels. This malfunction evokes 'neuropathic pain' which may also result from abnormal function of higher brain structures where ocular TG neurons project. Eye diseases or ocular surface surgery cause different levels of inflammation and/or nerve injury, which in turn activate sensory fibers of the eye in a variable

  4. Concentration change of TGF -β 1 in aqueous humor of rabbits.

    PubMed

    Yu, Xiao-Yi; Wu, Wei; Lu, Xiao-He

    2014-03-01

    To observe the influence of the the transforming growth factor β1 (TGF-β1) eye drops on rabbit aqueous humor TGF-β1 concentration, and to analyze the best drug concentration. A total of 30 New Zealand white rabbits were randomly divided into 5 groups with 6 in each. Rabits in control group had PBS eye drops, group A, B, C, D adopted TGF-β1 eye drops at 0.5, 1.0, 2.0, 4.0 mg/L, respectively, 4 times a day. Aqueous humor of right eye was extracted 1 week after administration to detect concentration changes of TGF-β1 by ELISA; rabbits in fpur hroups adopted 2.0 mg/L eye drops to left eyes 4 times a day, 0.2 mL aqueous humor was extracted left eye at the scheduled time point 0, 30 min, 2 h, 4 h, 24 h for testing, the slit lamp was used to observe the cornea, chamber and lens. No obvious pathological changes in conjunctiva, cornea, rabbit conjunctival, anterior chamber, and the lens was found. Concentration of TGF-β1 in rabbit aqueous humor in C, D group was significantly higher than the control group (P<0.05). TGF-β1 eye drops at 2.0 mg/L, 4.0 mg/L can significantly increase concentration of TGF-β1 in rabbit aqueous humor, withe good ocular surfac permeability. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  5. Preventing Eye Injuries

    MedlinePlus

    ... Stories Español Eye Health / Eye Health A-Z Eye Injuries Sections Preventing Eye Injuries Recognizing and Treating ... Infographic Five Steps to Safer Champagne Celebrations Preventing Eye Injuries Reviewed by: Brenda Pagan-Duran MD Mar. ...

  6. Intravitreal docosahexaenoic acid in a rabbit model: preclinical safety assessment.

    PubMed

    Dolz-Marco, Rosa; Gallego-Pinazo, Roberto; Pinazo-Duran, M Dolores; Pons-Vázquez, Sheila; Domingo-Pedro, Joan Carles; Díaz-Llopis, Manuel

    2014-01-01

    The purpose of the present study was to evaluate the retinal toxicity of a single dose of intravitreal docosahexaenoic acid (DHA) in rabbit eyes over a short-term period. Sixteen New Zealand albino rabbits were selected for this pre-clinical study. Six concentrations of DHA (Brudy Laboratories, Barcelona, Spain) were prepared: 10 mg/50 µl, 5 mg/50 µl, 2'5 mg/50 µl, 50 µg/50 µl, 25 µg/50 µl, and 5 µg/50 µl. Each concentration was injected intravitreally in the right eye of two rabbits. As a control, the vehicle solution was injected in one eye of four animals. Retinal safety was studied by slit-lamp examination, and electroretinography. All the rabbits were euthanized one week after the intravitreal injection of DHA and the eyeballs were processed to morphologic and morphometric histological examination by light microscopy. At the same time aqueous and vitreous humor samples were taken to quantify the concentration of omega-3 acids by gas chromatography. Statistical analysis was performed by SPSS 21.0. Slit-lamp examination revealed an important inflammatory reaction on the anterior chamber of the rabbits injected with the higher concentrations of DHA (10 mg/50 µl, 5 mg/50 µl, 2'5 mg/50 µ) Lower concentrations showed no inflammation. Electroretinography and histological studies showed no significant difference between control and DHA-injected groups except for the group injected with 50 µg/50 µl. Our results indicate that administration of intravitreal DHA is safe in the albino rabbit model up to the maximum tolerated dose of 25 µg/50 µl. Further studies should be performed in order to evaluate the effect of intravitreal injection of DHA as a treatment, alone or in combination, of different retinal diseases.

  7. Contact transcleral ciliary body photodynamic therapy with verteporfin in pigmented rabbits: effect of repeated treatments.

    PubMed

    Charisis, Spyridon K; Naoumidi, Irene I; Ginis, Harilaos S; Detorakis, Efstathios T; Tsilimbaris, Miltiadis K

    2010-01-01

    We studied the effect on the intraocular pressure (IOP) and the ciliary body (CB) morphology after four consecutive contact transcleral photodynamic treatments of the ciliary body (CB-PDT) with verteporfin in pigmented rabbits. Twenty-two pigmented rabbits underwent CB-PDT (study group), performed once (six rabbits) or repeated for up to four times (16 rabbits). Six additional rabbits received only laser treatment without photosensitizer administration (control group). CB-PDT was performed in one eye in rabbits of the study group, with the fellow eye serving as internal control. Verteporfin dosage was 1 mg kg(-1) as bolus injection and laser settings were 40 mW (600 microm core optical fiber) for 1.5 min per spot, for 10 spots. In repeated CB-PDT, treatments were performed in 4-day intervals. Daily IOP measurements were recorded. Histological studies were performed at selected time points. An IOP reduction, more sustained following repeated treatments, was detected in all treated eyes but not in fellow eyes or in the control group. On the average, the IOP was restored to pretreatment levels 4 days after the last treatment. No serious adverse events were observed and the CB architecture was intact at the end of the experiment. Repeated CB-PDT is safe and results in a short-term reduction of IOP. Induced CB alterations are reversible.

  8. Oil well rabbit

    SciTech Connect

    Yerian, H.W.

    1983-10-18

    A well rabbit is described which has a high gas seal capacity as well as resistance to wear and structural failure. The rabbit comprises a one-piece elongated generally cylindrical body having external circumferential gas-sealing grooves spaced along its length and a set of helically oriented slots at its lower end. The circumferential grooves, which work collectively in the manner of a labyrinth seal, are undercut in a way to deflect escaping gas streams and promote turbulence to enhance their gas-sealing capability. The undercut profile and relative spacing of the grooves leaves a large surface area between the grooves for distributing radial forces and thereby decreasing the wear rate of the rabbit. The helically oriented slots convert energy of upward escaping gas into rotational energy in the rabbit. (3 claims.

  9. The influence of He-Ne laser on scar formation after trabeculectomy in rabbits

    PubMed Central

    Hu, Jun; Li, Gui-Gang; Zhang, Hong; Xiang, Nan; Chen, Zhi-Qi; Wang, Rui-Lin; Xiang, Yan; Li, Bin; Li, Zheng-Jia; He, Yan-Yan; Wang, Li-Fang

    2010-01-01

    AIM To investigate the influence of He-Ne lasers on scar formation in the filtration canal after trabeculectomy in a rabbit model, as well as to explore the mechanisms for preventing scar formation when using He-Ne lasers in vivo. METHODS Experiment 1: Four groups were established (four eyes in each group). In 12 eyes, the upper nasal limbus area next to the upper rectus muscle received 10 minutes of He-Ne laser irradiation (100, 150, 200mW/cm2; 60, 90, 120J/cm2) every day for three days. Four eyes served as controls. Twenty-four hours after the final irradiation, the rabbits were sacrificed and the irradiated tissue was excised, fixed with paraformaldehyde and tested for proliferating cell nuclear antigen (PCNA), connective tissue growth factor (CTGF) and apoptosis (TUNEL). Experiment 2: Forty-two rabbits were randomly divided into two groups and standard trabeculectomy was performed in the right eyes either after 200mW/cm2 He-Ne laser irradiation or not in the filtration area. The expression of PCNA and CTGF, apoptosis and collagen density in the filtration area were tested on the 7th, 14th and 28th day after surgery. RESULTS Experiment 1: There were no more PCNA and CTGF positive cells in the He-Ne irradiation group than in the control group. No apoptotic cells were found in either group. Experiment 2: The expression of PCNA and CTGF was lower in the He-Ne irradiation group than in the control group on the 7th and 14th day after trabeculectomy surgery (P<0.05); no apoptotic cells were detected in either group. Collagen density was significantly lower in the He-Ne irradiation group than in the control group on the 14th and 28th day after surgery (P<0.05). CONCLUSION Pretreating the filtration area with 200mW/cm2 (120J/cm2) of He-Ne laser irradiation may be helpful in preventing scar formation after trabeculectomy, possibly due to the downregulation of the expression of PCNA, CTGF and collagen synthesis in fibroblasts. PMID:22553536

  10. Large Amounts of Reactivated Virus in Tears Precedes Recurrent Herpes Stromal Keratitis in Stressed Rabbits Latently Infected with Herpes Simplex Virus.

    PubMed

    Perng, Guey-Chuen; Osorio, Nelson; Jiang, Xianzhi; Geertsema, Roger; Hsiang, Chinhui; Brown, Don; BenMohamed, Lbachir; Wechsler, Steven L

    2016-01-01

    Recurrent herpetic stromal keratitis (rHSK), due to an immune response to reactivation of herpes simplex virus (HSV-1), can cause corneal blindness. The development of therapeutic interventions such as drugs and vaccines to decrease rHSK have been hampered by the lack of a small and reliable animal model in which rHSK occurs at a high frequency during HSV-1 latency. The aim of this study is to develop a rabbit model of rHSK in which stress from elevated temperatures increases the frequency of HSV-1 reactivations and rHSK. Rabbits latently infected with HSV-1 were subjected to elevated temperatures and the frequency of viral reactivations and rHSK were determined. In an experiment in which rabbits latently infected with HSV-1 were subjected to ill-defined stress as a result of failure of the vivarium air conditioning system, reactivation of HSV-1 occurred at over twice the normal frequency. In addition, 60% of eyes developed severe rHSK compared to <1% of eyes normally. All episodes of rHSK were preceded four to five days prior by an unusually large amount of reactivated virus in the tears of that eye and whenever this unusually large amount of reactivated virus was detected in tears, rHSK always appeared 4-5 days later. In subsequent experiments using well defined heat stress the reactivation frequency was similarly increased, but no eyes developed rHSK. The results reported here support the hypothesis that rHSK is associated not simply with elevated reactivation frequency, but rather with rare episodes of very high levels of reactivated virus in tears 4-5 days earlier.

  11. Large Amounts of Reactivated Virus in Tears Precedes Recurrent Herpes Stromal Keratitis in Stressed Rabbits Latently Infected with Herpes Simplex Virus

    PubMed Central

    Perng, Guey-Chuen; Osorio, Nelson; Jiang, Xianzhi; Geertsema, Roger; Hsiang, Chinhui; Brown, Don; BenMohamed, Lbachir; Wechsler, Steven L.

    2017-01-01

    Aim Recurrent herpetic stromal keratitis (rHSK), due to an immune response to reactivation of herpes simplex virus (HSV-1), can cause corneal blindness. The development of therapeutic interventions such as drugs and vaccines to decrease rHSK have been hampered by the lack of a small and reliable animal model in which rHSK occurs at a high frequency during HSV-1 latency. The aim of this study is to develop a rabbit model of rHSK in which stress from elevated temperatures increases the frequency of HSV-1 reactivations and rHSK. Materials and methods Rabbits latently infected with HSV-1 were subjected to elevated temperatures and the frequency of viral reactivations and rHSK were determined. Results In an experiment in which rabbits latently infected with HSV-1 were subjected to ill-defined stress as a result of failure of the vivarium air conditioning system, reactivation of HSV-1 occurred at over twice the normal frequency. In addition, 60% of eyes developed severe rHSK compared to <1% of eyes normally. All episodes of rHSK were preceded four to five days prior by an unusually large amount of reactivated virus in the tears of that eye and whenever this unusually large amount of reactivated virus was detected in tears, rHSK always appeared 4–5 days later. In subsequent experiments using well defined heat stress the reactivation frequency was similarly increased, but no eyes developed rHSK. Conclusions The results reported here support the hypothesis that rHSK is associated not simply with elevated reactivation frequency, but rather with rare episodes of very high levels of reactivated virus in tears 4–5 days earlier. PMID:25859798

  12. Targeted delivery of hyaluronic acid to the ocular surface by a polymer-peptide conjugate system for dry eye disease.

    PubMed

    Lee, David; Lu, Qiaozhi; Sommerfeld, Sven D; Chan, Amanda; Menon, Nikhil G; Schmidt, Tannin A; Elisseeff, Jennifer H; Singh, Anirudha

    2017-06-01

    Hyaluronic acid (HA) solutions effectively lubricate the ocular surface and are used for the relief of dry eye related symptoms. However, HA undergoes rapid clearance due to limited adhesion, which necessitates frequent instillation. Conversely, highly viscous artificial tear formulations with HA blur vision and interfere with blinking. Here, we developed an HA-eye drop formulation that selectively binds and retains HA for extended periods of time on the ocular surface. We synthesized a heterobifunctional polymer-peptide system with one end binding HA while the other end binding either sialic acid-containing glycosylated transmembrane molecules on the ocular surface epithelium, or type I collagen molecule within the tissue matrix. HA solution was mixed with the polymer-peptide system and tested on both ex vivo and in vivo models to determine its ability to prolong HA retention. Furthermore, rabbit ocular surface tissues treated with binding peptides and HA solutions demonstrated superior lubrication with reduced kinetic friction coefficients compared to tissues treated with conventional HA solution. The results suggest that binding peptide-based solution can keep the ocular surface enriched with HA for prolonged times as well as keep it lubricated. Therefore, this system can be further developed into a more effective treatment for dry eye patients than a standard HA eye drop. Eye drop formulations containing HA are widely used to lubricate the ocular surface and relieve dry eye related symptoms, however its low residence time remains a challenge. We designed a polymer-peptide system for the targeted delivery of HA to the ocular surface using sialic acid or type I collagen as anchors for HA immobilization. The addition of the polymer-peptide system to HA eye drop exhibited a reduced friction coefficient, and it can keep the ocular surface enriched with HA for prolonged time. This system can be further developed into a more effective treatment for dry eye than a

  13. Hypercholesterolemia Impaired Sperm Functionality in Rabbits

    PubMed Central

    Monclus, Maria A.; Cabrillana, Maria E.; Clementi, Marisa A.; Espínola, Leandro S.; Cid Barría, Jose L.; Vincenti, Amanda E.; Santi, Analia G.; Fornés, Miguel W.

    2010-01-01

    Hypercholesterolemia represents a high risk factor for frequent diseases and it has also been associated with poor semen quality that may lead to male infertility. The aim of this study was to analyze semen and sperm function in diet-induced hypercholesterolemic rabbits. Twelve adult White New Zealand male rabbits were fed ad libitum a control diet or a diet supplemented with 0.05% cholesterol. Rabbits under cholesterol-enriched diet significantly increased total cholesterol level in the serum. Semen examination revealed a significant reduction in semen volume and sperm motility in hypercholesterolemic rabbits (HCR). Sperm cell morphology was seriously affected, displaying primarily a “folded head”-head fold along the major axe-, and the presence of cytoplasmic droplet on sperm flagellum. Cholesterol was particularly increased in acrosomal region when detected by filipin probe. The rise in cholesterol concentration in sperm cells was determined quantitatively by Gas chromatographic-mass spectrometric analyses. We also found a reduction of protein tyrosine phosphorylation in sperm incubated under capacitating conditions from HCR. Interestingly, the addition of Protein Kinase A pathway activators -dibutyryl-cyclic AMP and iso-butylmethylxanthine- to the medium restored sperm capacitation. Finally, it was also reported a significant decrease in the percentage of reacted sperm in the presence of progesterone. In conclusion, our data showed that diet-induced hypercholesterolemia adversely affects semen quality and sperm motility, capacitation and acrosomal reaction in rabbits; probably due to an increase in cellular cholesterol content that alters membrane related events. PMID:20976152

  14. Measurement of Tear Production in English Angora and Dutch Rabbits.

    PubMed

    Rajaei, Seyed Mehdi; Rafiee, Siamak Mashhady; Ghaffari, Masoud Selk; Masouleh, Mohammad N; Jamshidian, Mahmoud

    2016-03-01

    The purpose of this study was to establish normal values for tear production tests in different breeds of domestic rabbits. Healthy adult rabbits (n = 60; 120 eyes) of 2 different breeds (English angora and Dutch; n = 15 of each sex and breed) were used in this study. Tear production was measured by using the 1-min Schirmer tear test (STT), phenol red thread test (PRTT), and endodontic absorbent paper point tear test (EAPTT). In addition, horizontal palpebral fissure length was evaluated as a measure of ocular adnexal dimensions. Tear production (mean ± 1 SD) in English angora rabbits was 5.4 ± 1.6 mm/min according to the STT, 25.0 ± 2.7 mm in 15 s for the PRTT, and 18.8 ± 2.1 mm/min by the EAPTT; in Dutch rabbits, these values were 4.6 ± 1.2 mm/min, 23.6 ± 2.3 mm in 15 s, and 16.9 ± 1.7 mm/min, respectively. Only the EAPTT revealed a significant difference in tear production between English Angora and Dutch rabbits. These results provide reference values for tear production in English Angora and Dutch rabbits according to 3 different quantitative tear film assessment methods.

  15. Retinal toxicity of intravitreal tenecteplase in the rabbit

    PubMed Central

    Rowley, S A; Vijayasekaran, S; Yu, P K; McAllister, I L; Yu, D-Yi

    2004-01-01

    Aim: To investigate the retinal toxicity of intravitreal injection of a novel fibrinolytic tenecteplase in rabbit eyes. Methods: Tenecteplase (25–350 μg in 0.1 ml BSS) was injected into the vitreous cavity of normal rabbit eyes. Control (fellow) eyes received 0.1 ml of BSS. One day, 1 week, and 2 months post-injection, the eyes were examined by slit lamp biomicroscopy, indirect ophthalmoscopy, and electroretinography, and then harvested for histopathological examination. Results: No evidence of retinal toxicity was seen with tenecteplase doses up to and including 50 μg. At a dose of 150 μg ophthalmoscopy was normal, but histology showed mild retinal damage in the inner nuclear layer and electroretinography showed a temporary reduction in B-wave amplitude. At doses of 200 μg and above, there was evidence of retinal toxicity on electroretinography, ophthalmoscopy, and histology. Ophthalmoscopic findings included vitreal fibrosis, retinal necrosis and tractional retinal detachment and light microscopy revealed necrosis of retinal pigment epithelium and other retinal layers. Damage was centred around the injection site but was more widespread with the higher doses. Conclusion: A dose of 50 μg tenecteplase appears safe for intravitreal injection in the rabbit. Tenecteplase could have potential applications in the treatment of submacular haemorrhage and retinal vein occlusion. PMID:15031179

  16. Viral diseases of the rabbit.

    PubMed

    Krogstad, Aric P; Simpson, Janet E; Korte, Scott W

    2005-01-01

    Viral disease in the rabbit is encountered infrequently by the clinical practitioner; however, several viral diseases were reported to occur in this species. Viral diseases that are described in the rabbit primarily may affect the integument, gastrointestinal tract or, central nervous system or maybe multi-systemic in nature. Rabbit viral diseases range from oral papillomatosis, with benign clinical signs, to rabbit hemorrhagic disease and myxomatosis, which may result in significant clinical disease and mortality. The wild rabbit may serve as a reservoir for disease transmission for many of these viral agents. In general, treatment of viral disease in the rabbit is supportive in nature.

  17. The injured eye

    PubMed Central

    Scott, Robert

    2011-01-01

    Eye injuries come at a high cost to society and are avoidable. Ocular blast injuries can be primary, from the blast wave itself; secondary, from fragments carried by the blast wind; tertiary; due to structural collapse or being thrown against a fixed object; or quaternary, from burns and indirect injuries. Ballistic eye protection significantly reduces the incidence of eye injuries and should be encouraged from an early stage in Military training. Management of an injured eye requires meticulous history taking, evaluation of vision that measures the acuity and if there is a relative pupillary defect as well as careful inspection of the eyes, under anaesthetic if necessary. A lateral canthotomy with cantholysis should be performed immediately if there is a sight-threatening retrobulbar haemorrhage. Systemic antibiotics should be prescribed if there is a suspected penetrating or perforating injury. A ruptured globe should be protected by an eye shield. Primary repair of ruptured globes should be performed in a timely fashion. Secondary procedures will often be required at a later date to achieve sight preservation. A poor initial visual acuity is not a guarantee of a poor final result. The final result can be predicted after approximately 3–4 weeks. Future research in eye injuries attempts to reduce scarring and neuronal damage as well as to promote photoreceptor rescue, using post-transcriptional inhibition of cell death pathways and vaccination to promote neural recovery. Where the sight has been lost sensory substitution of a picture from a spectacle mounted video camera to the touch receptors of the tongue can be used to achieve appreciation of the outside world. PMID:21149360

  18. Proteus species isolated from human eyes.

    PubMed

    Okumoto, M; Smolin, G; Belfort, R; Kim, H B; Siverio, C E

    1976-04-01

    Of 34 species of Proteus isolated from human eyes, 29 (85%) were P. mirabilis and five (15%) were P. morganii. In vitro antibiotic sensitivity studies showed that gentamicin best controlled both P. mirabilis and P. morganii of all the antibiotics tested. In vivo tests on experimental Proteus infections of rabbit coreas, treated with gentamicin and tobramycin, yielded comparable clinical results, but gentamicin was more effective in eliminating the organism from the experimental lesions.

  19. Sealing Penetrating Eye Injuries Using Photoactivated Bonding

    DTIC Science & Technology

    2012-09-01

    the iris. The human iris contains melanin in the stromal layer and in a pigmented epithelial layer on the posterior surface. When the melanin ...skin pigmentation varies the standard is not clear. The distribution and amount of melanin and vasculature in the iris differs from that of the retina...these measurements because the iris is darkly pigmented (high melanin content) whereas the albino rabbit eyes used in our studies lack melanin in

  20. Cyclosporine Amicellar delivery system for dry eyes.

    PubMed

    Kang, Han; Cha, Kwang-Ho; Cho, Wonkyung; Park, Junsung; Park, Hee Jun; Sun, Bo Kyung; Hyun, Sang-Min; Hwang, Sung-Joo

    2016-01-01

    The objectives of this study were to develop stable cyclosporine A (CsA) ophthalmic micelle solutions for dry-eye syndrome and evaluate their physicochemical properties and therapeutic efficacy. CsA-micelle solutions (MS-CsA) were created by a simple method with Cremophor EL, ethanol, and phosphate buffer. We investigated the particle size, pH, and osmolarity. In addition, long-term physical and chemical stability for MS-CsA was observed. To confirm the therapeutic efficacy, tear production in dry eye-induced rabbits was evaluated using the Schirmer tear test (STT). When compared to a commercial product, Restasis, MS-CsA demonstrated improvement in goblet-cell density and conjunctival epithelial morphology, as demonstrated in histological hematoxylin and eosin staining. MS-CsA had a smaller particle size (average diameter 14-18 nm) and a narrow size distribution. Physicochemical parameters, such as particle size, pH, osmolarity, and remaining CsA concentration were all within the expected range of 60 days. STT scores significantly improved in MS-CsA treated groups (P<0.05) in comparison to those of the Restasis-treated group. The number of goblet cells for rabbit conjunctivas after the administration of MS-CsA was 94.83±8.38, a significantly higher result than the 65.17±11.51 seen with Restasis. The conjunctival epithelial morphology of dry eye-induced rabbits thinned with loss of goblet cells. However, after 5 days of treatment with drug formulations, rabbit conjunctivas recovered epithelia and showed a relative increase in the number of goblet cells. The results of this study indicate the potential use of a novel MS for the ophthalmic delivery of CsA in treating dry eyes.

  1. Cyclosporine Amicellar delivery system for dry eyes

    PubMed Central

    Kang, Han; Cha, Kwang-Ho; Cho, Wonkyung; Park, Junsung; Park, Hee Jun; Sun, Bo Kyung; Hyun, Sang-Min; Hwang, Sung-Joo

    2016-01-01

    Background The objectives of this study were to develop stable cyclosporine A (CsA) ophthalmic micelle solutions for dry-eye syndrome and evaluate their physicochemical properties and therapeutic efficacy. Materials and methods CsA-micelle solutions (MS-CsA) were created by a simple method with Cremophor EL, ethanol, and phosphate buffer. We investigated the particle size, pH, and osmolarity. In addition, long-term physical and chemical stability for MS-CsA was observed. To confirm the therapeutic efficacy, tear production in dry eye-induced rabbits was evaluated using the Schirmer tear test (STT). When compared to a commercial product, Restasis, MS-CsA demonstrated improvement in goblet-cell density and conjunctival epithelial morphology, as demonstrated in histological hematoxylin and eosin staining. Results MS-CsA had a smaller particle size (average diameter 14–18 nm) and a narrow size distribution. Physicochemical parameters, such as particle size, pH, osmolarity, and remaining CsA concentration were all within the expected range of 60 days. STT scores significantly improved in MS-CsA treated groups (P<0.05) in comparison to those of the Restasis-treated group. The number of goblet cells for rabbit conjunctivas after the administration of MS-CsA was 94.83±8.38, a significantly higher result than the 65.17±11.51 seen with Restasis. The conjunctival epithelial morphology of dry eye-induced rabbits thinned with loss of goblet cells. However, after 5 days of treatment with drug formulations, rabbit conjunctivas recovered epithelia and showed a relative increase in the number of goblet cells. Conclusion The results of this study indicate the potential use of a novel MS for the ophthalmic delivery of CsA in treating dry eyes. PMID:27382280

  2. Confocal Microscopy Of The Eye.

    NASA Astrophysics Data System (ADS)

    Masters, Barry R.

    1989-12-01

    A laser scanning confocal microscope was used to study the structure of human donor eyes and enucleated rabbit eyes. Reflected light confocal images were obtained with a Leitz water immersion objective (50X, NA 1.0). A drop of bicarbonate Ringer's was placed between the objective and the tissue to optically couple the tissue. The confocal microscope was used to image the following objects within the eye: superficial epithelial cells, super basal and basal epithelial cells, basement membrane, stromal nerve plexus, nerve fibers, nuclei and cell bodies of stromal keratocytes, cell processes of stromal keratocytes, Descemet's membrane, and the endothelial cells. In addition, the ocular lens and excised retina were imaged. The confocal microscope produces images of the eye with the following enhanced features: increased lateral resolution, decreased depth of field, and increased contrast of transparent ocular structures. It is concluded that confocal imaging systems are an improvement over traditional optical instruments, and they may develop into a new tool for basic visual science and clinical ophthalmology.

  3. Clinical symptoms and diagnosis of encephalitozoonosis in pet rabbits.

    PubMed

    Künzel, Frank; Gruber, Andrea; Tichy, Alexander; Edelhofer, Renate; Nell, Barbara; Hassan, Jasmin; Leschnik, Michael; Thalhammer, Johann G; Joachim, Anja

    2008-02-14

    Infections with Encephalitozoon cuniculi in rabbits are observed at increasing frequency and are known as opportunistic infections in immunocompromised humans. 191 pet rabbits with suspected encephalitozoonosis, presented at the Animal Hospital of the Veterinary University of Vienna (Austria), were included in this study. Rabbits were serologically examined for antibodies against E. cuniculi (144 positive out of 184 rabbits with suspected encephalitozoonosis compared to 14 positive out of 40 clinically healthy rabbits tested as part of a standard health check) and Toxoplasma gondii (8 positive out of 157). Of the 144 seropositive rabbits with clinical signs, 75% showed neurological symptoms, 14.6% demonstrated phacoclastic uveitis and 3.5% suffered from renal failure. 6.9% of the animals had combined symptoms. Vestibular disease dominated within the rabbits that showed neurological symptoms. Polymerase chain reaction (PCR) could not detect parasite DNA in urine or cerebrospinal fluid (CSF), but did so in 4 out of 5 samples of liquefied lens material in cases with phacoclastic uveitis due to lens capsule rupture. Additionally further diagnostic procedures, such as inspection of the external ear canal (N=69), radiography of the tympanic bullae (N=65) were performed to rule out differential diagnosis. 54.2% of the patients exhibiting neurological symptoms recovered within a few days, while 87.5% of the rabbits suffering from renal failure died or had to be euthanized.

  4. Eye and orbit ultrasound

    MedlinePlus

    Echography - eye orbit; Ultrasound - eye orbit; Ocular ultrasonography; Orbital ultrasonography ... ophthalmology department of a hospital or clinic. Your eye is numbed with medicine (anesthetic drops). The ultrasound ...

  5. Eye Twitching

    MedlinePlus

    ... aspects of life. Hemifacial spasm involves twitches of muscles on one side of the face, including the eyelid. Eye twitching usually goes away on its own within a few days or weeks with rest, stress relief and decreased caffeine. Schedule an appointment with your doctor if: The ...

  6. Googly Eyes

    ERIC Educational Resources Information Center

    Boss, Susan

    2009-01-01

    Beverage take-out trays are funky in their form and function. In this article, the author describes how to make googly eye masks out of discarded take-out trays and other common recycled or discarded materials. (Contains 1 online resource.)

  7. Proliferation of the vascular endothelium of the iris following total debridement of the corneal epithelium and limbal excision of rabbits.

    PubMed

    Góes, Rejane Maira; Barbosa, Flávia Leão; de Faria-E-Sousa, Sidney Júlio; Kajiwara, João Kazuyuki; Haddad, Antonio

    2008-07-01

    Damage to the corneal epithelium causes not only a reaction for its repair but also affects other parts of the cornea as well as different components of the anterior segment of the eye. The purpose of this investigation was to analyze the consequences, following epithelial and limbal damage, to the iris of rabbits (Oryctolagus cuniculus). The corneal epithelium was thoroughly scraped followed by surgical excision of the limbus. Next, (3)H-thymidine ((3)H-TdR) was injected intravitreally both into the right (experimental) and left (control) eyes which had their anterior segments processed for autoradiography at intervals of 2, 7 and 21 days after surgery (three rabbits per interval). The irises were also examined with scanning-electron and confocal microscopy after Evans blue injection. There was a high frequency of labeling in the cells of the iris blood vessels in the experimental eye, particularly the endothelial ones. The ratio of labeled cells between experimental and control irises was 40:1, with a population of nuclei increasing by 25% and remaining labeled up to 21 days. There was also an increase in the volume of the iris vasculature as shown by confocal microscopy. The high labeling frequencies of the vascular cells were observed throughout the iris from the ciliary to the pupillary regions. The lesions on the corneal epithelium elicit proliferation of the iris vascular cells, mainly its endothelium, as well as an early breakdown of the blood-aqueous barrier. The daughter cells resulting from the damage to the eye surface were detected up to 21 days after a single injection of (3)H-TdR, most likely due to their slow turnover. As a consequence of this proliferation, the vasculature of the iris increased in volume.

  8. Nerve growth factor enhances sleep in rabbits.

    PubMed

    Takahashi, S; Krueger, J M

    1999-04-02

    Nerve growth factor (NGF) elicits rapid-eye-movement sleep (REMS) in cats. Removal of NGF receptor-positive cholinergic basal forebrain neurons inhibits REMS in rats. The aim of the present study was to determine the effects of NGF on sleep and brain temperature (Tbr) in rabbits. Male rabbits were implanted with electroencephalograph (EEG) electrodes, a brain thermistor and an intraventricular (i.c.v.) guide cannula. Rabbits received human beta-NGF i.c.v. (0.01, 0.1, 1.0 or 10 microg] and on a separate day, 25 microl pyrogen-free saline i.c.v. as control. EEG and Tbr were recorded for 23 h after injections. The highest two doses of NGF increased both non-REMS and REMS across the 23-h recording period. REMS was enhanced dose-dependently. Tbr was not affected by any dose of NGF. These results suggest that NGF is involved in both REMS and non-REMS regulation.

  9. ApoE knockout rabbits: A novel model for the study of human hyperlipidemia.

    PubMed

    Niimi, Manabu; Yang, Dongshan; Kitajima, Shuji; Ning, Bo; Wang, Chuan; Li, Shen; Liu, Enqi; Zhang, Jifeng; Eugene Chen, Y; Fan, Jianglin

    2016-02-01

    Rabbits are one of the best animal models for the study of hyperlipidemia and atherosclerosis. Although many transgenic rabbits have been created, the development of gene knockout (KO) rabbits has been impossible due to the lack of rabbit embryonic stem cells. We along with others recently generated KO rabbits using genome editing techniques. In the current study, we characterized the lipoprotein profiles of apoE KO rabbits on both chow and cholesterol diets and investigated their susceptibility to a diet-induced atherosclerosis. We analyzed plasma lipids and lipoproteins of apoE KO rabbits and compared them with those of wild-type rabbits. On a chow diet, homozygous (but not heterozygous) apoE KO rabbits showed mild hyperlipidemia and, when challenged with a cholesterol diet, they showed greater susceptibility to diet-induced hyperlipidemia than did the wild-type rabbits and their plasma total cholesterol levels were remarkably increased (1070 ± 61 mg/dL in apoE KO vs. 169 ± 79 mg/dL in the wild type, p < 0.001). Hyperlipidemia in apoE KO rabbits was caused by elevated remnant lipoproteins. Interestingly, increased remnant lipoproteins in apoE KO rabbits were predominated by apoB-48 and rich in both apoA-I and apoA-IV contents. Furthermore, apoE KO rabbits developed greater aortic atherosclerosis than wild-type rabbits when fed with a cholesterol diet for 10 weeks. To our knowledge, this is the first report of generating KO rabbits for the study of lipid and lipoprotein metabolism. ApoE KO rabbits should be a useful model for the study of human hyperlipidemia and atherosclerosis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Dorsal eye selector pannier (pnr) suppresses the eye fate to define dorsal margin of the Drosophila eye

    PubMed Central

    Oros, Sarah M.; Tare, Meghana; Kango-Singh, Madhuri; Singh, Amit

    2010-01-01

    Axial patterning is crucial for organogenesis. During Drosophila eye development, dorso-ventral (DV) axis determination is the first lineage restriction event. The eye primordium begins with a default ventral fate, on which the dorsal eye fate is established by expression of the GATA-1 transcription factor pannier (pnr). Earlier, it was suggested that loss of pnr function induces enlargement in the dorsal eye due to ectopic equator formation. Interestingly, we found that in addition to regulating DV patterning, pnr suppresses the eye fate by downregulating the core retinal determination genes eyes absent (eya), sine oculis (so) and dacshund (dac) to define the dorsal eye margin. We found that pnr acts downstream of Ey and affect the retinal determination pathway by suppressing eya. Further analysis of the “eye suppression” function of pnr revealed that this function is likely mediated through suppression of the homeotic gene teashirt (tsh) and is independent of homothorax (hth), a negative regulator of eye. Pnr expression is restricted to the peripodial membrane on the dorsal eye margin, which gives rise to head structures around the eye, and pnr is not expressed in the eye disc proper that forms the retina. Thus, pnr has dual function, during early developmental stages pnr is involved in axial patterning whereas later it promotes the head specific fate. These studies will help in understanding the developmental regulation of boundary formation of the eye field on the dorsal eye margin. PMID:20691679

  11. The Ex Vivo Eye Irritation Test as an alternative test method for serious eye damage/eye irritation.

    PubMed

    Spöler, Felix; Kray, Oya; Kray, Stefan; Panfil, Claudia; Schrage, Norbert F

    2015-07-01

    Ocular irritation testing is a common requirement for the classification, labelling and packaging of chemicals (substances and mixtures). The in vivo Draize rabbit eye test (OECD Test Guideline 405) is considered to be the regulatory reference method for the classification of chemicals according to their potential to induce eye injury. In the Draize test, chemicals are applied to rabbit eyes in vivo, and changes are monitored over time. If no damage is observed, the chemical is not categorised. Otherwise, the classification depends on the severity and reversibility of the damage. Alternative test methods have to be designed to match the classifications from the in vivo reference method. However, observation of damage reversibility is usually not possible in vitro. Within the present study, a new organotypic method based on rabbit corneas obtained from food production is demonstrated to close this gap. The Ex Vivo Eye Irritation Test (EVEIT) retains the full biochemical activity of the corneal epithelium, epithelial stem cells and endothelium. This permits the in-depth analysis of ocular chemical trauma beyond that achievable by using established in vitro methods. In particular, the EVEIT is the first test to permit the direct monitoring of recovery of all corneal layers after damage. To develop a prediction model for the EVEIT that is comparable to the GHS system, 37 reference chemicals were analysed. The experimental data were used to derive a three-level potency ranking of eye irritation and corrosion that best fits the GHS categorisation. In vivo data available in the literature were used for comparison. When compared with GHS classification predictions, the overall accuracy of the three-level potency ranking was 78%. The classification of chemicals as irritating versus non-irritating resulted in 96% sensitivity, 91% specificity and 95% accuracy. 2015 FRAME.

  12. Epidemiology of viral haemorrhagic disease and myxomatosis in a free-living population of wild rabbits.

    PubMed

    Calvete, C; Estrada, R; Villafuerte, R; Osácar, J J; Lucientes, J

    2002-06-22

    From January 1993 to June 1996, the epidemiology of myxomatosis and viral haemorrhagic disease (VHD) was studied in a free-living population of wild rabbits (Oryctolagus cuniculus) in Spain by means of serological surveys and radiotracking. Myxomatosis was endemic and associated with the breeding period. Its serological pattern was characterised by a 100 per cent prevalence of antibodies in adult rabbits and a rapid increase in antibodies in young rabbits in their first year. No mortality from myxomatosis was detected in adults, and mortality in young rabbits could not be estimated because of interference by predators and scavengers and the deaths of many radiotagged rabbits inside their burrows. VHD was also an endemic disease associated with the breeding period. Adults had a higher prevalence of antibodies against VHD than young rabbits, reaching values of 80 to 90 per cent. During the study, there was an increase in rabbit numbers as a result of a decrease in mortality from predation which was associated with an increase in mortality due to VHD and in the prevalence of antibodies to VHD. Mortality from VHD was lower in rabbits with VHD antibodies than in seronegative rabbits, but some mortality from the disease was also detected in seropositive rabbits. The annual mean mortality rate due to VHD in adult rabbits was estimated to be 21.8 per cent.

  13. Outbreak of sarcoptic mange and malasseziasis in rabbits (Oryctolagus cuniculus).

    PubMed

    Radi, Zaher A

    2004-08-01

    An outbreak of combined Sarcoptes and Malassezia spp. infection was diagnosed in a rabbitry. About 20 (4%) of 500 rabbits were affected. Two 6- to 8-month-old female Holland Lops rabbits were submitted to the Tifton Diagnostic & Investigational Laboratory at The University of Georgia for complete necropsy. Gross lesions consisted of marked multifocal areas of alopecia, crusting, and dermatitis around the eye and on ears, nose, lips, neck, abdomen, feet, and external genitalia. Histologic examination of the skin revealed epidermal acanthosis with marked parakeratotic hyperkeratosis and cross sections of embedded mites consistent with Sarcoptes sp. and budding yeasts consistent with Malassezia sp. To the best of the author's knowledge, this is the first case report of combined Sarcoptes and Malassezia spp. infection in rabbits.

  14. Susceptibility to cartap-induced lethal effect and diaphragmatic injury via ocular exposure in rabbits.

    PubMed

    Liao, Jiunn-Wang; Pang, Victor Fei; Jeng, Chian-Ren; Chang, Shao-Kuang; Hwang, Jenn-Sheng; Wang, Shun-Cheng

    2003-11-05

    Cartap is extensively used to control agricultural pests. Pertinent literatures have indicated that it causes no eye irritation [D.E. Ray, Insecticides derived from plants and other organisms, in: W.J. Hayes, E.R. Laws (Eds.), Handbook of Insecticide Toxicology, Classes of Insecticides, vol. 2, Academic Press, New York, 1991, p. 611; C. Tomlin, Cartap, in: C. Tomlin (Ed.), The Insecticide Manual, 12th ed., British Crop Protection Council, Surrey, UK, 2000, p. 144]; however, the instillation of a little cartap through the eye has caused death in rabbits. The aim of this study was to determine the ocular toxicity of cartap in New Zealand White rabbits. Cartap was directly instilled into the low conjunctival sac of eyes, at doses of 0, 5, 7.5, 10 and 12.5 mg/kg body weight. The changes in the enzymes and isoenzymes of creatine kinase (CK), lactate dehydrogenase (LD), as well as pathological changes in the muscles of the heart, thigh and diaphragm were determined in the cartap-treated rabbits. Moreover, the neuromuscular effect of cartap was examined using the isolated rabbit phrenic-nerve diaphragm model. The results indicated that rabbits developed severe signs and they died within 20 min of ocular instillation. The ocular LD50 of cartap was 8.1 mg/kg body weight. Treatment with cartap increased the activities of CK and LD enzymes and their isoenzymes, CK-1, CK-2, and CK-3 in serum, and CK-3 and LD-5 in the diaphragm. Microscopically, hypercontraction bands and the rupture of myofibers of the diaphragm were observed in dead rabbits. Cartap did not affect nerve-evoked twitch but induced irreversible contracture and twitch depression on the isolated rabbit's diaphragm. These results indicate that the rabbit is susceptible to cartap toxicity; the effect of cartap caused contracture and damage to the diaphragm might play a pivotal role in respiratory paralysis and death of rabbits during intoxication.

  15. Rabbit as an animal model for intravitreal pharmacokinetics: Clinical predictability and quality of the published data.

    PubMed

    Del Amo, Eva M; Urtti, Arto

    2015-08-01

    Intravitreal administration is the method of choice in drug delivery to the retina and/or choroid. Rabbit is the most commonly used animal species in intravitreal pharmacokinetics, but it has been criticized as being a poor model of human eye. The critique is based on some anatomical differences, properties of the vitreous humor, and observed differences in drug concentrations in the anterior chamber after intravitreal injections. We have systematically analyzed all published information on intravitreal pharmacokinetics in the rabbit and human eye. The analysis revealed major problems in the design of the pharmacokinetic studies. In this review we provide advice for study design. Overall, the pharmacokinetic parameters (clearance, volume of distribution, half-life) in the human and rabbit eye have good correlation and comparable absolute values. Therefore, reliable rabbit-to-man translation of intravitreal pharmacokinetics should be feasible. The relevant anatomical and physiological parameters in rabbit and man show only small differences. Furthermore, the claimed discrepancy between drug concentrations in the human and rabbit aqueous humor is not supported by the data analysis. Based on the available and properly conducted pharmacokinetic studies, the differences in the vitreous structure in rabbits and human patients do not lead to significant pharmacokinetic differences. This review is the first step towards inter-species translation of intravitreal pharmacokinetics. More information is still needed to dissect the roles of drug delivery systems, disease states, age and ocular manipulation on the intravitreal pharmacokinetics in rabbit and man. Anyway, the published data and the derived pharmacokinetic parameters indicate that the rabbit is a useful animal model in intravitreal pharmacokinetics. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Determination of aldose reductase activity in the eye by localized magnetic resonance spectroscopy.

    PubMed

    Lizak, M J; Mori, K; Kador, P F

    2001-10-01

    The polyol pathway plays an important role in the formation of diabetic complications of the eye. Due to variations in the pharmacokinetic properties of aldose reductase inhibitors and variations in the degradation of the blood-ocular barrier, it is often difficult to determine the proper intraocular levels of aldose reductase inhibitor required for inhibition of aldose reductase activity in ocular tissues. Utilizing localized magnetic resonance spectroscopy (MRS), the present method can determine adequate inhibition of aldose reductase activity in the lens by noninvasively measuring polyol pathway activity in the eye. New Zealand White rabbits, under anesthesia, were administered an intravitreal injection of 3-fluoro-3-deoxy-D-glucose (3FDG). Localized MRS was then used to assess polyol pathway activity by determining the levels of 3-fluoro-3-deoxy-D-sorbitol (3FS) and 3-fluoro-3-deoxy-D-fructose (3FF) metabolite formation from 3FDG in the eye. MRS was able to follow the loss of 3FDG from the vitreous into the anterior segment of the eye and particularly into the lens and aqueous. The primary metabolism of 3FDG observed by MRS was the formation of 3FS in the lens that is catalyzed by aldose reductase. Production of 3FS was linear in time and decreased with the oral administration of an aldose reductase inhibitor.

  17. Eye Complications in IBD

    MedlinePlus

    ... Home > Resources > Eye Complications in IBD Go Back Eye Complications in IBD Email Print + Share Approximately 10% ... doctor’s attention sooner rather than later. TYPES OF EYE DISORDERS UVEITIS One of the most common eye ...

  18. Eye Injuries at Work

    MedlinePlus

    ... Ophthalmologist Patient Stories Español Eye Health / Tips & Prevention Eye Injuries Sections Preventing Eye Injuries Recognizing and Treating ... Numbers — Infographic Five Steps to Safer Champagne Celebrations Eye Injuries at Work Edited by: Shirley Dang Feb. ...

  19. Conjunctivitis (Pink Eye)

    MedlinePlus

    ... can be embedded on web pages. Conjunctivitis (Pink Eye) One-Page Overview Pink, itchy eyes? Conjunctivitis – or ... yourself from getting and spreading pink eye . Pink Eye: What To Do Discusses causes and treatment, when ...

  20. Eye Injuries at Home

    MedlinePlus

    ... Ophthalmologist Patient Stories Español Eye Health / Tips & Prevention Eye Injuries Sections Preventing Eye Injuries Recognizing and Treating ... Numbers — Infographic Five Steps to Safer Champagne Celebrations Eye Injuries at Home Reviewed by: Brenda Pagan-Duran ...

  1. Eye muscle repair - discharge

    MedlinePlus

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  2. Why Do Eyes Water?

    MedlinePlus

    ... Happens in the Operating Room? Why Do Eyes Water? KidsHealth > For Kids > Why Do Eyes Water? A ... out of your nose. continue Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  3. Why Do Eyes Water?

    MedlinePlus

    ... Lifesaver Kids Talk About: Coaches Why Do Eyes Water? KidsHealth > For Kids > Why Do Eyes Water? Print ... out of your nose. continue Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  4. Eye Movement Disorders

    MedlinePlus

    ... t work properly. There are many kinds of eye movement disorders. Two common ones are Strabismus - a disorder ... of the eyes, sometimes called "dancing eyes" Some eye movement disorders are present at birth. Others develop over ...

  5. The rabbit as an experimental and production animal: from genomics to proteomics.

    PubMed

    Miller, Ingrid; Rogel-Gaillard, Claire; Spina, Domenico; Fontanesi, Luca; de Almeida, Andre M

    2014-03-01

    The rabbit (Oryctolagus cuniculus) is an important animal species widely used for biomedical research purposes, meat production and as a pet animal. There are numerous biomedical and scientific applications that include important areas such as antibody production, muscle, eye and circulatory physiology. The use of proteomics has been limited when considering this species. The aim of this article is to provide a review on applications of proteomics to the rabbit species, including those that are most relevant and where rabbit is a key species: muscle and circulatory system physiology.

  6. Thymoma-associated exfoliative dermatitis in a rabbit.

    PubMed

    Florizoone, Koenraad

    2005-08-01

    A 5-year-old rabbit with generalized scaling is presented. Multiple skin scrapings and acetate tape impressions were negative for mites and Malassezia. Culture for dermatophytes was also negative. Skin biopsies showed similarities with sebaceous adenitis described in rabbits (absence of sebaceous glands, perifollicular lymphocytic infiltrate at the level of the absent sebaceous glands, lymphocytic mural folliculitis, interface dermatitis). The owners refused any treatment and 2 months later the rabbit was euthanized due to anorexia. At necropsy a mass was found in the anterior mediastinum. Histopathology confirmed a diagnosis of thymoma. A possible paraneoplastic skin disease was suspected, based on similarities with thymoma-associated exfoliative dermatitis in cats.

  7. In-vivo laser-induced bubbles in the primate eye with femtosecond pulses

    NASA Astrophysics Data System (ADS)

    Cain, Clarence P.; DiCarlo, Cheryl D.; Noojin, Gary D.; Amnotte, Rodney E.; Rockwell, Benjamin A.; Roach, William P.

    1996-05-01

    Threshold measurements for laser-induced breakdown (LIB) and bubble generation for femtosecond laser pulsewidths have been made in vivo for rhesus monkey eyes. These LIB thresholds are compared with model-predicted thresholds for water and minimum visible lesion thresholds in Dutch Belted rabbit and rhesus monkey eyes. LIB thresholds in biological materials including vitreous, normal saline, tap water, and ultrapure water have been measured and reported using an artificial eye. We have recorded on video the first LIB causing bubble formation in any eye in vivo using albino rabbit eyes, pigmented rabbit eyes, and rhesus monkey eyes. External optics were used to focus the image within the vitreous and the bubbles generated were clearly formed anterior to the retina within the vitreous humor. The length of time that the bubbles are visible depends on the pulse energy delivered and may last for several seconds. However, for pulse energies near thresholds, the bubbles have a very short lifetime and may be seen on the video for only one frame. The plasma formation at the breakdown site acts as a limiting mechanism for energy transmission and may explain why high-energy femtosecond pulses at energies up to 100 microjoules sometimes do not cause severe damage to the retina. This fact may also explain why it is so difficult to product hemmorrhagic lesions in either the rabbit or primate eye with 100-femtosecond laser pulses.

  8. Testing of the Safety and the Effectiveness of Using SamjeongPharmacopuncture Solution as Eye drops

    PubMed Central

    Seo, Hyung-Sik; Lee, Dong-Jin

    2012-01-01

    Objective: This experimental study was designed to investigate the safety and the effectiveness of Samjeong pharmacopuncture solution (SPS) manufactured by using a the lowtemperature extract on process. Methods: To identify the safety and the effectiveness of using SPS as eye drops, we performed applied eye irritation tests on rabbits and antibacterial tests for Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, and Candida albicans. The eye irritation test was performed according to the toxicity testing regulation of the Korea Food & Drug Administration (2009. 8. 24, KFDA 2009-116). After SPS had been applied on the left eye of the rabbits, eye irritation in the cornea, iris and conjunctiva was observed on the 1st, 2nd, 3rd, 4th & 7th day. After SPS had been dropped on bacterial species that cause keratitis, the minimum inhibition concentration and the size of the inhibition zone were measured. The anti-bacterial potency was also measured by taking the size of inhibition zone. Results: After SPS had been administered on the left eye of the rabbits, none of nine rabbits were found to show abnormal signs or weight changes. After SPS had been administered on the left eye of the rabbits, no eye irritation in the cornea, iris and conjunctiva was observed on the 1st, 2nd, 3rd, 4th & 7th day. No specific response was detected in MIC for bacterial species Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, and Candida albicans after SPS had been applied. Conclusions: This study suggests that SPS is a non-toxic and non-irritant medicine that does not cause any of eye irritation in rabbits, but it has no antibacterial effects on bacterial species that are well known to cause keratitis. These results suggest that more research is required on extracts from herbal medicines for treating keratitis. PMID:25780632

  9. A Step by Step Protocol for Subretinal Surgery in Rabbits

    PubMed Central

    Al-Nawaiseh, Sami; Thieltges, Fabian; Liu, Zengping; Strack, Claudine; Brinken, Ralf; Braun, Norbert; Wolschendorf, Marc; Maminishkis, Arvydas; Eter, Nicole; Stanzel, Boris V.

    2016-01-01

    Age related macular degeneration (AMD), retinitis pigmentosa, and other RPE related diseases are the most common causes for irreversible loss of vision in adults in industrially developed countries. RPE transplantation appears to be a promising therapy, as it may replace dysfunctional RPE, restore its function, and thereby vision. Here we describe a method for transplanting a cultured RPE monolayer on a scaffold into the subretinal space (SRS) of rabbits. After vitrectomy xenotransplants were delivered into the SRS using a custom made shooter consisting of a 20-gauge metallic nozzle with a polytetrafluoroethylene (PTFE) coated plunger. The current technique evolved in over 150 rabbit surgeries over 6 years. Post-operative follow-up can be obtained using non-invasive and repetitive in vivo imaging such as spectral domain optical coherence tomography (SD-OCT) followed by perfusion-fixed histology. The method has well-defined steps for easy learning and high success rate. Rabbits are considered a large eye animal model useful in preclinical studies for clinical translation. In this context rabbits are a cost-efficient and perhaps convenient alternative to other large eye animal models. PMID:27684952

  10. A Step by Step Protocol for Subretinal Surgery in Rabbits.

    PubMed

    Al-Nawaiseh, Sami; Thieltges, Fabian; Liu, Zengping; Strack, Claudine; Brinken, Ralf; Braun, Norbert; Wolschendorf, Marc; Maminishkis, Arvydas; Eter, Nicole; Stanzel, Boris V

    2016-09-13

    Age related macular degeneration (AMD), retinitis pigmentosa, and other RPE related diseases are the most common causes for irreversible loss of vision in adults in industrially developed countries. RPE transplantation appears to be a promising therapy, as it may replace dysfunctional RPE, restore its function, and thereby vision. Here we describe a method for transplanting a cultured RPE monolayer on a scaffold into the subretinal space (SRS) of rabbits. After vitrectomy xenotransplants were delivered into the SRS using a custom made shooter consisting of a 20-gauge metallic nozzle with a polytetrafluoroethylene (PTFE) coated plunger. The current technique evolved in over 150 rabbit surgeries over 6 years. Post-operative follow-up can be obtained using non-invasive and repetitive in vivo imaging such as spectral domain optical coherence tomography (SD-OCT) followed by perfusion-fixed histology. The method has well-defined steps for easy learning and high success rate. Rabbits are considered a large eye animal model useful in preclinical studies for clinical translation. In this context rabbits are a cost-efficient and perhaps convenient alternative to other large eye animal models.

  11. Eye contricks

    PubMed Central

    Wade, Nicholas J

    2011-01-01

    Pictorial images are icons as well as eye-cons: they provide distillations of objects or ideas into simpler shapes. They create the impression of representing that which cannot be presented. Even at the level of the photograph, the links between icon and object are tenuous. The dimensions of depth and motion are missing from icons, and these alone introduce all manner of potential ambiguities. The history of art can be considered as exploring the missing link between icon and object. Eye-cons can also be illusions—tricks of vision so that what is seen does not necessarily correspond to what is physically presented. Pictorial images can be spatialised or stylised; spatialised images generally share some of the projective characteristics of the object represented. Written words are also icons, but they do not resemble the objects they represent—they are stylised or conventional. Icons as stylised words and spatialised images were set in delightful opposition by René Magritte in a series of pipe paintings, and this theme is here alluded to. Most of visual science is now concerned with icons—two-dimensional displays on computer monitors. Is vision now the science of eye-cons? PMID:23145240

  12. Black Eye: First Aid

    MedlinePlus

    First aid Black eye: First aid Black eye: First aid By Mayo Clinic Staff A black eye is caused by bleeding under the skin around the eye. Most injuries that cause a black eye aren't serious. But a black eye ...

  13. Experimental intracameral injection of vancomycin microparticles in rabbits.

    PubMed

    Kodjikian, Laurent; Couprie, Jérémy; Hachicha, Walid; Timour, Quadiri; Devouassoux, Mojgan; Builles, Nicolas; Hartmann, Daniel; Fessi, Hatem

    2010-08-01

    To evaluate the in vivo toxicity and efficacy of previously developed poly-(lactide-co-glycolide)-vancomycin-based microparticles (V-MPLs) for eventual use for endophthalmitis prophylaxis during cataract surgery. The intraocular vancomycin concentration profile was evaluated after V-MPL injection into the anterior chamber of rabbit eyes. The toxicology of V-MPLs versus MPLs alone was tested by corneal cellular counting and retinal histology. The prophylactic efficacy of the V-MPLs was evaluated by bacterial counts after introducing contaminated intraocular lenses (IOLs) together with the V-MPLs into one anterior chamber of phakic rabbit eyes or without V-MPLs in control rabbit eyes. Intraocular V-MPLs produced effective vancomycin concentrations over at least 6 hours. Corneal counts revealed no significant increase in dead cells. Retinal toxicity manifested as inflammation 3 hours after injection, reaching its maximum between 12 hours and 24 hours, decreasing by 48 hours, and completely disappearing at 72 hours. Inflammation was similar between V-MPLs and MPLs. Untreated eyes implanted with highly infected IOLs showed severe, reproducible endophthalmitis. No sign of infection was observed with infected IOLs and concomitant V-MPL treatment, supported by bacterial counts showing a significant decrease in colony-forming Staphylococcus epidermidis units in the anterior chamber and on the implant surfaces within 6 hours. The present study demonstrated the release and toxicologic properties of the authors' newly developed V-MPLs in vivo. In addition, the rabbit model shows that V-MPLs are effective in reducing the risk of experimental endophthalmitis.

  14. Effect of tropicamide on ocular blood flow in the rabbit

    SciTech Connect

    Delgado, D.; Michel, P.; Jaanus, S.D.

    1982-05-01

    Intracardiac injection of 15 microspheres labeled with /sup 85/Sr (strontium) and /sup 141/Ce (cerium) were used to determine ocular blood flow in seven rabbits before and 25 min after bilateral application of tropicamide to the cornea. By using two different isotopes distinguishable under gammaspectrometry, each animal served as its own control. After administration of two drops of 1% tropicamide, no significant difference in blood flow between treated and untreated eyes was observed.

  15. Rho-Associated Kinase Inhibitor Eye Drop (Ripasudil) Transiently Alters the Morphology of Corneal Endothelial Cells.

    PubMed

    Okumura, Naoki; Okazaki, Yugo; Inoue, Ryota; Nakano, Shinichiro; Fullwood, Nigel J; Kinoshita, Shigeru; Koizumi, Noriko

    2015-11-01

    Ripasudil (Glanatec), a selective Rho-associated coiled coil-containing protein kinase (ROCK) inhibitor, was approved in Japan in September 2014 for the treatment of glaucoma and ocular hypertension. The purpose of this study was to investigate the effect of ripasudil eye drops on corneal endothelial morphology, as ROCK signaling is known to modulate the actin cytoskeleton. Morphological changes in the corneal endothelium were evaluated in human subjects by specular and slit-lamp microscopy, following topical administration of ripasudil. We also used a rabbit model to evaluate the effect of ripasudil on clinical parameters of the corneal endothelium. Twenty-four hours after ripasudil application, corneal specimens were evaluated by phalloidin staining, immunohistochemical analysis, and electron microscopy. Specular microscopy revealed morphological changes in human eyes, and slit-lamp microscopy showed guttae-like findings. The rabbit model showed morphological changes similar to those seen in human eyes after ripasudil administration. Electron microscopy demonstrated that these alterations are due to the formation of protrusions along the cell-cell borders, but this formation is transient. Expression of corneal endothelial function-related markers was not disrupted; corneal thickness and corneal volume were not changed; and no cell death was observed following ripasudil administration. Ripasudil induces transient guttae-like findings in humans, most likely due to protrusion formation along intracellular borders caused by the reduction in actomyosin contractility of the corneal endothelial cells. No severe adverse effects were observed. Physicians should be aware that ROCK inhibitors can cause these guttae-like findings, to avoid misdiagnosing patients as having Fuchs endothelial corneal dystrophy. (www.umin.ac.jp/ctr number, UMIN000018340.).

  16. Evaluation of Eye Irritation Potential of Aqueous Leaf Extract of Achyranthes aspera by In Vitro and In Vivo Method.

    PubMed

    Rajpal Deshmukh, Gajanan; Hema Kumar, Kuntrapakam; Suresh Reddy, Poojari Venkata; Srinivasa Rao, Boddapati; Venkata Satish Kumar, Chirumamilla

    2012-01-01

    The present paper is an attempt to investigate the eye irritation potential of aqueous leaf extract of Achyranthes aspera by in vitro, Hen's Egg Chorioallantoic Membrane Test (HET-CAM) and in vivo acute eye irritation test in rabbits. The irritation score (IS) obtained after treatment of the extract on HET-CAM is 0.07 and that of in rabbits is 0.55, Which does not comes under either category 1 or 2 as per the harmonized integrated classification system. The aqueous extract of Achyranthes aspera showed no eye irritation properties both in vitro and in vivo methods when compared with negative control whereas positive controls showed eye irritation potential.

  17. Biomechanics of sclera crosslinked using genipin in rabbit

    PubMed Central

    Liu, Tai-Xiang; Wang, Zheng

    2017-01-01

    AIM To strengthen the biomechanics of collagen by crosslinking rabbit scleral collagen with genipin to develop a new therapy for preventing myopic progression. METHODS Ten New Zealand rabbits were treated with 0.5 mmol/L genipin injected into the sub-Tenon's capsule in the right eyes. Untreated contralateral eyes served as the control. The treated area was cut into scleral strips measuring 4.0 mm×10.0 mm for stress-strain measurements (n=5). The remaining five treated eyes were prepared for histological examination. RESULTS Compared to the untreated scleral strips, the genipin-crosslinked scleral strips showed that the ultimate stress and Young's modulus at 10% strain were increased by the amplitude of 130% and 303% respectively, ultimate strain was decreased by 24%. There had no α-smooth muscle actin (α-SMA) positive cells in control and treated sclera. Histologically, there was no sign of apoptosis in the sclera, choroid, and retina; and no side effects were found in the peripheral cornea and optic nerve adjacent to the treatment area. CONCLUSION Genipin induced crosslinking of collagen can increase its biomechanical behavior by direct strengthening of the extracellular matrix in rabbit sclera, with no α-SMA expression seen in the myofibroblasts. As there is no evidence of cytotoxicity in the scleral, choroidal, and retinal cells, genipin is likely a promising agent to strengthen the weakened sclera to prevent myopic progression. PMID:28393024

  18. Biomechanics of sclera crosslinked using genipin in rabbit.

    PubMed

    Liu, Tai-Xiang; Wang, Zheng

    2017-01-01

    To strengthen the biomechanics of collagen by crosslinking rabbit scleral collagen with genipin to develop a new therapy for preventing myopic progression. Ten New Zealand rabbits were treated with 0.5 mmol/L genipin injected into the sub-Tenon's capsule in the right eyes. Untreated contralateral eyes served as the control. The treated area was cut into scleral strips measuring 4.0 mm×10.0 mm for stress-strain measurements (n=5). The remaining five treated eyes were prepared for histological examination. Compared to the untreated scleral strips, the genipin-crosslinked scleral strips showed that the ultimate stress and Young's modulus at 10% strain were increased by the amplitude of 130% and 303% respectively, ultimate strain was decreased by 24%. There had no α-smooth muscle actin (α-SMA) positive cells in control and treated sclera. Histologically, there was no sign of apoptosis in the sclera, choroid, and retina; and no side effects were found in the peripheral cornea and optic nerve adjacent to the treatment area. Genipin induced crosslinking of collagen can increase its biomechanical behavior by direct strengthening of the extracellular matrix in rabbit sclera, with no α-SMA expression seen in the myofibroblasts. As there is no evidence of cytotoxicity in the scleral, choroidal, and retinal cells, genipin is likely a promising agent to strengthen the weakened sclera to prevent myopic progression.

  19. The Cutaneous Rabbit Revisited

    ERIC Educational Resources Information Center

    Flach, Rudiger; Haggard, Patrick

    2006-01-01

    In the cutaneous rabbit effect (CRE), a tactile event (so-called attractee tap) is mislocalized toward an adjacent attractor tap. The effect depends on the time interval between the taps. The authors delivered sequences of taps to the forearm and asked participants to report the location of one of the taps. The authors replicated the original CRE…

  20. The Cutaneous Rabbit Revisited

    ERIC Educational Resources Information Center

    Flach, Rudiger; Haggard, Patrick

    2006-01-01

    In the cutaneous rabbit effect (CRE), a tactile event (so-called attractee tap) is mislocalized toward an adjacent attractor tap. The effect depends on the time interval between the taps. The authors delivered sequences of taps to the forearm and asked participants to report the location of one of the taps. The authors replicated the original CRE…

  1. Autoantibody Production in Rabbits

    PubMed Central

    Asherson, G. L.; Dumonde, D. C.

    1963-01-01

    The sera of rabbits injected with rat liver, kidney, heart, muscle, spleen and brain in Freund's complete adjuvant fixed complement with rabbit tissue. This complement-fixing activity was attributed to autoantibodies which were able to fix complement in vitro with the tissue of the rabbit in which they occurred. Absorption, gel diffusion and antibody and antigen titrations indicated that some of the anti-liver, anti-kidney, anti-heart, anti-muscle and anti-brain sera contained organ-specific autoantibody. The sera also contained autoantibody reacting with widely distributed antigen(s), which was relatively labile at 65°. The anti-kidney and anti-brain sera reacted with distinct antigens which were extracted from rabbit kidney and brain with a mixture of chloroform and methanol. The natural autoantibody of Kidd and Friedewald was usually labile at 65° and behaved like a macroglobulin on sucrose gradient centrifugation. Sera taken 1 week after immunization with rat tissue contained heat-labile macroglobulin antibody. However, sera taken 1 month after immunization also contained small molecular weight antibody which was stable at 65°. PMID:13965166

  2. Strabismus and eye muscle function.

    PubMed

    Lennerstrand, Gunnar

    2007-11-01

    Studies of external eye muscle morphology and physiology are reviewed, with respect to both motor and sensory functions in concomitant strabismus. The eye muscles have a more complex fibre composition than other striated muscle, and they are among the fastest and most fatigue-resistant muscles in the body. However, it is not generally believed that concomitant strabismus is due to a primary abnormality of the eye muscles or the ocular motor system. The gross anatomy of eye muscles, including the shape and position of the eye muscle pulleys, was not changed in strabismus. The histology of the eye muscle fibres was also basically the same, but changes have been observed in the cellular and biochemical machinery of the fibres, most notably in the singly innervated orbital fibres. Functionally, this was seen as slower contractions and reduced fatigue resistance of eye muscles in animals with strabismus and defects of binocular vision. Most likely the changes represented an adaptation to modified visual demands on the ocular motor control, because of the defects of binocular vision in strabismus from an early age. Adaptation of eye muscle function to visual demands could be seen also in the adult human ocular motor system, but here the effects could be reversed with treatment in some conditions. External eye muscles in the human have sensory organs, muscle spindles and tendon organs, responding to changes in muscle force and length. It is not known how these proprioceptors are used more specifically in ocular motor control, and there is no stretch reflex in the external eye muscles. However, a clear influence on space localization and eye position can be demonstrated with vibratory stimulation of the eye muscles, presumably activating muscle spindles. Different effects were observed in normal subjects and in adult patients with strabismus, which would indicate that the proprioceptive input from one eye of strabismic patients could be suppressed by the other eye, similar

  3. Rabbit retinal neovascularization induced by latex angiogenic-derived fraction: an experimental model.

    PubMed

    Sampaio, R B; Mendonca, R J; Simioni, A R; Costa, R A; Siqueira, R C; Correa, V M; Tedesco, A C; Haddad, A; Coutinho Netto, J; Jorge, R

    2010-01-01

    To create a retinal neovascularization experimental model using intravitreal injection of microspheres loaded with latex-derived angiogenic fraction. Thirty-two albino New Zealand rabbits, divided in 4 groups of 8 animals, were enrolled in this study. Rabbits in groups I, II, and III received one intravitreal injection of PLGA (L-lactide-co-glycolide) microspheres with 10, 30, and 50 microg of latex-derived angiogenic fraction into their right eyes, respectively, and group IV received 0.1 ml of microspheres without the angiogenic fraction. Weekly follow-up with ophthalmoscopy and fluorescein angiography was performed; the rabbits were sacrificed in the 4th week and their eyes processed for light microscopy. All eyes from group I demonstrated increased retinal vascular tortuosity, observed from 14 days after injection and maintained for 28 days, otherwise without new vessels detection. All group II eyes showed vascular changes similar to group I. Fifty percent of the eyes from group II rabbits developed retinal neovascularization 21 days after injection. All eyes from group III demonstrated significant vascular tortuosity and retinal new vessels 2 weeks after injection, progressing to fibrovascular proliferation and tractional retinal detachment. No vascular changes or retinal new vessels were observed in group IV eyes. Light microscopy confirmed the existence of new vessels previously seen on fluorescein angiography, in retinal sections adjacent to the optic disc, not observed in sections at the same area in the control group. Thirty- and 50-microg microspheres containing latex-derived angiogenic fraction injected into the vitreous cavity induced retinal neovascularization in rabbits.

  4. Rabbit models for the study of human atherosclerosis: from pathophysiological mechanisms to translational medicine

    PubMed Central

    Fan, Jianglin; Kitajima, Shuji; Watanabe, Teruo; Xu, Jie; Zhang, Jifeng; Liu, Enqi; Chen, Y. Eugene

    2014-01-01

    Laboratory animal models play an important role in the study of human diseases. Using appropriate animals is critical not only for basic research but also for the development of therapeutics and diagnostic tools. Rabbits are widely used for the study of human atherosclerosis. Because rabbits have a unique feature of lipoprotein metabolism (like humans but unlike rodents) and are sensitive to a cholesterol diet, rabbit models have not only provided many insights into the pathogenesis and development of human atherosclerosis but also made a great contribution to translational research. In fact, rabbit was the first animal model used for studying human atherosclerosis, more than a century ago. Currently, three types of rabbit model are commonly used for the study of human atherosclerosis and lipid metabolism: (1) cholesterol-fed rabbits, (2) Watanabe heritable hyperlipidemic rabbits, analogous to human familial hypercholesterolemia due to genetic deficiency of LDL receptors, and (3) genetically modified (transgenic and knock-out) rabbits. Despite their importance, compared with the mouse, the most widely used laboratory animal model nowadays, the use of rabbit models is still limited. In this review, we focus on the features of rabbit lipoprotein metabolism and pathology of atherosclerotic lesions that make it the optimal model for human atherosclerotic disease, especially for the translational medicine. For the sake of clarity, the review is not an attempt to be completely inclusive, but instead attempts to summarize substantial information concisely and provide a guideline for experiments using rabbits. PMID:25277507

  5. Rabbit models for the study of human atherosclerosis: from pathophysiological mechanisms to translational medicine.

    PubMed

    Fan, Jianglin; Kitajima, Shuji; Watanabe, Teruo; Xu, Jie; Zhang, Jifeng; Liu, Enqi; Chen, Y Eugene

    2015-02-01

    Laboratory animal models play an important role in the study of human diseases. Using appropriate animals is critical not only for basic research but also for the development of therapeutics and diagnostic tools. Rabbits are widely used for the study of human atherosclerosis. Because rabbits have a unique feature of lipoprotein metabolism (like humans but unlike rodents) and are sensitive to a cholesterol diet, rabbit models have not only provided many insights into the pathogenesis and development of human atherosclerosis but also made a great contribution to translational research. In fact, rabbit was the first animal model used for studying human atherosclerosis, more than a century ago. Currently, three types of rabbit model are commonly used for the study of human atherosclerosis and lipid metabolism: (1) cholesterol-fed rabbits, (2) Watanabe heritable hyperlipidemic rabbits, analogous to human familial hypercholesterolemia due to genetic deficiency of LDL receptors, and (3) genetically modified (transgenic and knock-out) rabbits. Despite their importance, compared with the mouse, the most widely used laboratory animal model nowadays, the use of rabbit models is still limited. In this review, we focus on the features of rabbit lipoprotein metabolism and pathology of atherosclerotic lesions that make it the optimal model for human atherosclerotic disease, especially for the translational medicine. For the sake of clarity, the review is not an attempt to be completely inclusive, but instead attempts to summarize substantial information concisely and provide a guideline for experiments using rabbits.

  6. Spontaneous fatal Human herpesvirus 1 encephalitis in two domestic rabbits (Oryctolagus cuniculus).

    PubMed

    de Matos, Ricardo; Russell, Duncan; Van Alstine, William; Miller, Andrew

    2014-09-01

    Despite the particular susceptibility of the rabbit to experimental infection with Human herpesvirus 1 (HHV-1) and the high seroprevalence of HHV-1 in human beings, reports of natural infection in pet rabbits are rare. The current report describes 2 cases of HHV encephalitis in pet rabbits in North America. Antemortem clinical signs included seizures, ptyalism, and muscle tremors. Results of complete blood cell count and plasma biochemistry panel were unremarkable except for a mild leukocytosis in both cases. Both rabbits died after a short period of hospitalization. Rabbit 1 presented mild optic chiasm hemorrhage on gross examination, while rabbit 2 had no gross lesions. Histologic findings for both cases included lymphocytic and/or lymphoplasmacytic encephalitis with necrosis and the presence of intranuclear inclusion bodies in neurons and glial cells. Polymerase chain reaction (PCR) analysis of affected brain tissue using primers specific for Human herpesvirus 1 and 2 confirmed diagnosis of HHV encephalitis for rabbit 1. Immunohistochemical staining (poly- and monoclonal) and PCR analysis using primers specific to HHV-1 confirmed the diagnosis of HHV-1 encephalitis for rabbit 2. The owner of rabbit 2 was suspected to be the source of infection due to close contact during an episode of herpes labialis. Given the high susceptibility of rabbits to experimental HHV-1, high seroprevalence of HHV-1 in human beings, and severity of clinical disease in this species, clinician awareness and client education is important for disease prevention. Human herpesvirus 1 encephalitis should be considered as a differential diagnosis for rabbits with neurologic disease.

  7. Autoantibody production in rabbits

    PubMed Central

    Asherson, G. L.; Holborow, E. J.

    1966-01-01

    Rabbits received two injections of dead bacteria in Freund's complete adjuvant. One month later the sera of the rabbits were examined for autoantibodies against gut by indirect immunofluorescence using the rabbit's own stomach, ileum and colon taken at post mortem. Autoantibodies against colon were found in three out of seven rabbits injected with one particular strain of Escherichia coli O64 and in a few animals injected with other E. coli, Salmonella arizona, Proteus mirabilis, Klebsiella pneumoniae and Streptococcus faecalis. The antigen, with which the autoantibodies reacted, behaved like mucus and was detected in the colon and sometimes in the ileum and the stomach. Three patterns of staining were observed: (a) staining of the superficial mucosa of the colon with sparing of the deep glands; (b) staining of scattered groups of glands in the deepest part of the colon with sparing of the superficial glands (this pattern of staining was associated with staining of the superficial mucosa of the body of the stomach); and (c) staining of both the superficial and deep glands of the colon. None of the sera tested reacted with the bronchial or salivary glands. Polysaccharide preparations of the colon, but not the stomach, inhibited the reaction of the autoantibodies with colon in the sera tested. The amount of antigen needed to inhibit the basal staining was much greater than that needed to inhibit the superficial staining. It was concluded that rabbits may produce autoantibodies to colon and in some cases to ileum and stomach following the injection of certain dead bacteria in Freund's complete adjuvant. ImagesFIGS. 1-2FIG. 3FIG. 4FIG. 5FIG. 6 PMID:4956607

  8. Impact of pregnancy on zonisamide pharmacokinetics in rabbits.

    PubMed

    Matar, Kamal M

    2013-01-01

    Pregnancy is associated with various physiological changes which may lead to significant alterations in the pharmacokinetics of many drugs. The present study was aimed to investigate the potential effects of pregnancy on the pharmacokinetic profile of zonisamide (ZNM) in the rabbit. Seven female rabbits were used in this study. The pregnant and nonpregnant rabbits received ZNM orally at a dose of 10 mg/kg and blood samples were collected from the animals just before receiving the drug and then serially for up to 24 h. The plasma samples were analyzed using tandem mass spectrometric method. Following a single oral dose of ZNM to the rabbits, the mean values of ZNM plasma concentrations at different times were consistently low in pregnant compared to nonpregnant rabbits. The mean values of ZNM's Cmax and AUC0-∞ were significantly (P < 0.05) decreased, whereas the CL/F exhibited substantial increase (P < 0.05) in pregnant compared to nonpregnant rabbits. Tmax, t1/2abs, t1/2el, MRT, and Vd/F showed no significant differences between the two groups. The present study demonstrates that pregnancy decreased ZNM plasma concentrations in rabbits and that the decrease could be due to decreased extent of gastrointestinal absorption, induced hepatic metabolism, or enhanced renal elimination of the drug.

  9. Ectopic Six3 expression in the dragon eye goldfish.

    PubMed

    Ma, Dong-Mei; Zhu, Hua-Ping; Gui, Jian-Fang

    2008-02-01

    For goldfish (Carassius auratus), there are many varieties with different eye phenotypes due to artificial selection and adaptive evolution. Dragon eye is a variant eye characterized by a large-size eyeball protruding out of the socket similar to the eye of dragon in Chinese legends. In this study, anatomical structure of the goldfish dragon eye was compared with that of the common eye, and a stretching of the retina was observed in the enlarged dragon eye. Moreover, the homeobox-containing transcription factor Six3 cDNAs were cloned from the two types of goldfish, and the expression patterns were analyzed in both normal eye and dragon eye goldfish. No amino acid sequence differences were observed between the two deduced peptides, and the expression pattern of Six3 protein in dragon eye is quite similar to common eye during embryogenesis, but from 2 days after hatching, ectopic Six3 expression began to occur in the dragon eye, especially in the outer nuclear layer cells. With eye development, more predominant Six3 distribution was detected in the outer nuclear layer cells of dragon eye than that of normal eye, and fewer cell-layers in outer nuclear layer were observed in dragon eye retina than in normal eye retina. The highlight of this study is that higher Six3 expression occurs in dragon eye goldfish than in normal eye goldfish during retinal development of larvae.

  10. Characterization and localization of the rabbit ocular calcitonin gene-related peptide (CGRP)-receptor component protein (RCP).

    PubMed

    Rosenblatt, M I; Dahl, G P; Dickerson, I M

    2000-04-01

    To determine whether the calcitonin gene-related peptide (CGRP) receptor component protein (RCP), a novel signal transduction molecule, is required for CGRP signaling in the eye and to determine potential ocular sites of CGRP action. The cDNA for the rabbit ocular RCP homologue was cloned using a combination of reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). Function of the rabbit ocular RCP was assessed using a sensitive oocyte-based assay, which utilizes the protein kinase A (PKA)-sensitive cystic fibrosis transmembrane conductance regulator (CFTR) as a sensor of cAMP formation. RCP expression in the rabbit eye was localized using immunohistochemistry. A 2063-bp cDNA for the rabbit ocular RCP was cloned and sequenced. Expression of the rabbit RCP cDNA confers CGRP responsiveness in a sensitive oocyte-based assay. Antisense oligonucleotides made to the ocular RCP abolishes CGRP responsiveness of ciliary body and iris mRNA in the oocyte-CFTR assay. Localization of RCP protein in the rabbit eye using immunohistochemistry demonstrated RCP immunoreactivity in the ciliary body and iris blood vessels, as well as in layers of the ciliary epithelium. The rabbit ocular RCP appears to be required for signal transduction at ocular CGRP receptors and is localized to sites previously reported to bind CGRP, which affect intraocular pressure and neurogenic inflammation.

  11. Influence of glucocorticosteroids on the biomechanical properties of in-vivo rabbit cornea.

    PubMed

    Yu, Ji-guo; Bao, Fang-jun; Joda, Akram; Fu, Xun-an; Zhou, Shi; Wang, Jing; Hu, Xiu-li; Wang, Qin-mei; Elsheikh, Ahmed

    2014-01-01

    Understanding corneal biomechanical responses during long-term glucocorticosteroids administration is important in clinical practice. The purpose of this study is to investigate the biomechanical influence of fluorometholone 0.1% eye drops on rabbit cornea. Thirty-eight Japanese white rabbits were randomly divided into three groups; a fluorometholone group, a supernatant group and a blank control group. For each rabbit in fluorometholone group, one cornea was treated with fluorometholone 0.1% eye drops four times a day for 8 weeks, while corneas of rabbits in supernatant group were treated in the same frequency with supernatant fraction centrifuged from fluorometholone 0.1% eye drops. The rabbits in the blank control group were not given any treatment. At the end of the 8 week observation period, the rabbits were euthanized and the eyes immediately enucleated and prepared for inflation testing. The experimental pressure-deformation data was used to derive the stress-strain behavior of each eye using an inverse modeling procedure. Comparisons of mechanical stiffness of corneas were conducted among the three groups to determine the influence of fluorometholone. The results showed that corneal stiffness decreased as the fluorometholone administration time prolonged. Comparisons of tangent modulus indicated average stiffness reductions of 34.2% and 33.5% in the fluorometholone group compared to the supernatant and control groups, respectively, at the end of the observation period. The stiffness-reduction effect of fluorometholone on the cornea should be considered in clinical management, especially when administrating it to biomechanically weakened corneas, such as after refractive surgeries and in cases of keratoconus. © 2013 Published by Elsevier Ltd.

  12. From rabbit antibody repertoires to rabbit monoclonal antibodies

    PubMed Central

    Weber, Justus; Peng, Haiyong; Rader, Christoph

    2017-01-01

    In this review, we explain why and how rabbit monoclonal antibodies have become outstanding reagents for laboratory research and increasingly for diagnostic and therapeutic applications. Starting with the unique ontogeny of rabbit B cells that affords highly distinctive antibody repertoires rich in in vivo pruned binders of high diversity, affinity and specificity, we describe the generation of rabbit monoclonal antibodies by hybridoma technology, phage display and alternative methods, along with an account of successful humanization strategies. PMID:28336958

  13. Femtosecond-lentotomy treatment: six-month follow-up of in vivo treated rabbit lenses

    NASA Astrophysics Data System (ADS)

    Schumacher, S.; Fromm, M.; Oberheide, U.; Bock, P.; Imbschweiler, I.; Hoffmann, H.; Beineke, A.; Gerten, G.; Wegener, A.; Lubatschowski, H.

    2009-07-01

    Presbyopia is an age related effect which affects every human at the age of about 40 years. So far reading glasses are the conventional treatment. According to Helmholtz' theory of accommodation one of the mayor reasons for the development of presbyopia is the increasing sclerosis of the lens. In contrast to that the ciliary muscle and the lens capsule remain mostly active and elastic the whole life. So a possible treatment could be the increase of the flexibility of the lens by creating gliding planes with fs-laser pulses inside the lens tissue. In former studies it was shown that fs-laser pulses were able to increase the flexibility of ex vivo porcine lenses as well as ex vivo human donor lenses. Our current aim was to evaluate the effect of the fs-laser pulses on the crystalline lens of living rabbit eyes due to the fs-lentotomy treatment. The main focus of the evaluation was the exclusion of possible side effects of the treatment like cataract formation or retina damage. The treated eyes were monitored using optical coherence tomography (OCT) and Scheimpflug imaging for localizing and studying the tissue effects of the incisions. Furthermore histological sections of the lens and retina were prepared. The rabbits were investigated pre operatively and up to six months post operatively. The fs-laser induced micro incisions were successfully applied to the left lens of each rabbit. The micro incisions within the crystalline lens were detectable with OCT and Scheimpflug imaging up to six month. The imaging within the lens showed a progressive fading of the incisional opacities generated by the femtosecond laser during the six months and no indication of cataract formation was found. OCT and Scheimpflug images emphasize themselves as necessary tools to monitor the micro incisions over time. Histopathological sections of the lens tissue support the findings of the non invasive imaging techniques. Also the histopathological sections of the retina show no thermal

  14. Injury surveillance in construction: eye injuries.

    PubMed

    Welch, L S; Hunting, K L; Mawudeku, A

    2001-07-01

    Occupational eye injuries are both common and preventable. About 20% of occupational eye injuries occur in construction. To investigate the nature of eye injuries among construction workers, we analyzed a large data set of construction worker injuries. In addition, we interviewed 62 workers with eye injuries to further explore circumstances of eye injury and workers' attitudes and behavior toward the use of eye protection. Eleven percent (363 cases) of the 3,390 construction workers in our data set were treated for eye injuries. Welders, plumbers, insulators, painters/glaziers, supervisors, and electricians had a higher proportion of all injuries due to eye injuries than other trades. Nearly half of the diagnoses were abrasions (46%) followed by foreign objects or splash in the eye (29%), conjunctivitis (10%), and burns (5%). In the interviews with 62 workers, we found that employers very frequently required eye protection for all tasks or for high-risk tasks, and workers report wearing eye protection regularly. However, most did not wear eye protection with top and side shields; if we believe the injuries occurred because a particle or liquid passed between the glasses and the workers' faces, increased use of goggles or full shields would have prevented two-thirds of this group of injuries.

  15. Eye movement abnormalities.

    PubMed

    Moncayo, Jorge; Bogousslavsky, Julien

    2012-01-01

    Generation and control of eye movements requires the participation of the cortex, basal ganglia, cerebellum and brainstem. The signals of this complex neural network finally converge on the ocular motoneurons of the brainstem. Infarct or hemorrhage at any level of the oculomotor system (though more frequent in the brain-stem) may give rise to a broad spectrum of eye movement abnormalities (EMAs). Consequently, neurologists and particularly stroke neurologists are routinely confronted with EMAs, some of which may be overlooked in the acute stroke setting and others that, when recognized, may have a high localizing value. The most complex EMAs are due to midbrain stroke. Horizontal gaze disorders, some of them manifesting unusual patterns, may occur in pontine stroke. Distinct varieties of nystagmus occur in cerebellar and medullary stroke. This review summarizes the most representative EMAs from the supratentorial level to the brainstem.

  16. Thermoacoustic imaging of rabbit knee joints.

    PubMed

    Chi, Zihui; Zhao, Yuan; Huang, Lin; Zheng, Zhu; Jiang, Huabei

    2016-12-01

    Knee joint is one of the largest and most complex joints of the body. Knee joint diseases are common, and current clinical imaging technologies such as x-ray computed tomography, magnetic resonance imaging, and ultrasound imaging have limitations in the diagnosis of knee joint diseases. Emerging imaging technologies such as diffuse optical tomography and photoacoustic imaging (PAI) have been applied to the detection of osteoarthritis (OA). However, they are limited to small joints such as the finger and difficult to be used for large joints such as the knee. Thermoacoustic imaging (TAI), also an emerging modality, provides high contrast and deep tissue penetration. Here, the authors apply TAI to the knee joint and demonstrate the potential of TAI for imaging large joints. Adult New Zealand male rabbits (average weight = 2 kg) were chosen for this study. In a TAI experiment, a rabbit was placed in a holder to keep in a genuflex position after being injected with pentobarbital through its ear margin intravenous (30 mg/kg). The holder and the rabbit were then positioned under the horn antenna of the TAI system for signal acquisition and image reconstruction. After the experiment, the imaged knee joint was dissected and photographed. Identical procedures were performed for several rabbits (n = 4). Finally, detailed comparative analyses between TAI images and anatomical pictures of the knee joint were conducted. There were high similarities between the reconstructed TAI images and anatomical pictures of the knee joint, in terms of the shape and size of various knee joint tissues. TAI could clearly image ligament, fat pad, and other joint tissues. The differences in appearance of TAI images due to motion effect of the knee joint were also discussed. TAI could reveal details of rabbit knee joint in high resolution. As the recovered TAI images represent the dielectric property distributions of joint tissues, TAI may offer a new tool for noninvasive detection of joint

  17. Neurogenic cardiomyopathy in rabbits with experimentally induced rabies.

    PubMed

    Kesdangsakonwut, S; Sunden, Y; Yamada, K; Nishizono, A; Sawa, H; Umemura, T

    2015-05-01

    Cardiomyopathies have been rarely described in rabbits. Here we report myocardial necrosis of the ventricular wall in rabbits with experimentally induced rabies. Myocardial lesions were found only in rabbits with brain lesions, and the severity of the cardiac lesions was proportional to that of the brain lesions. Neither the frequency nor the cumulative dose of anesthesia was related to the incidence or the severity of the myocardial lesions. The myocardial lesions were characterized by degeneration and/or necrosis of myocardial cells and were accompanied by contraction band necrosis, interstitial fibrosis, and infiltration of inflammatory cells. The brain lesions due to rabies virus infection were most prominent in the cerebral cortex, thalamus, hypothalamus, brainstem, and medulla. Rabies virus antigen was not found in the hearts of any rabbits. Based on these findings, the myocardial lesions were classified as neurogenic cardiomyopathy.

  18. Reevaluation of lipolytic activity of growth hormone in rabbit adipocytes.

    PubMed

    Barenton, B; Batifol, V; Combarnous, Y; Dulor, J P; Durand, P; Vezinhet, A

    1984-07-18

    The lipolytic activities of porcine pituitary fractions and purified growth hormone (GH) from human (h), porcine (p), ovine (o) and rabbit (Rb) origin as well as ovine placental lactogen (oPL), were compared to that of ACTH on rabbit adipocytes. All the GH preparations and oPL were equivalent in inhibiting the binding of labelled oGH to liver plasma membranes from pregnant rabbits. ACTH, and to a lesser extent porcine pituitary fractions and hGH, stimulated free fatty acid production by isolated adipocytes. The sensitivity of the adipocytes to these factors was increased when adenosine deaminase was added to the incubation medium. But, RbGH, pGH, oGH and oPL had no effect. We conclude that GH is not directly involved in the control of lipolysis in rabbit adipocytes and that the effect of hGH is rather due to a contamination of this preparation by other pituitary factors.

  19. Rabbits killing birds revisited.

    PubMed

    Zhang, Jimin; Fan, Meng; Kuang, Yang

    2006-09-01

    We formulate and study a three-species population model consisting of an endemic prey (bird), an alien prey (rabbit) and an alien predator (cat). Our model overcomes several model construction problems in existing models. Moreover, our model generates richer, more reasonable and realistic dynamics. We explore the possible control strategies to save or restore the bird by controlling or eliminating the rabbit or the cat when the bird is endangered. We confirm the existence of the hyperpredation phenomenon, which is a big potential threat to most endemic prey. Specifically, we show that, in an endemic prey-alien prey-alien predator system, eradication of introduced predators such as the cat alone is not always the best solution to protect endemic insular prey since predator control may fail to protect the indigenous prey when the control of the introduced prey is not carried out simultaneously.

  20. Listeria infections of the eye.

    PubMed

    Hof, Herbert

    2017-03-10

    The bacterium Listeria monocytogenes resides originally in the environment. Infections of the eye have been induced experimentally; for example, in rabbits and guinea pigs. Natural ocular infections occur in various animals; in most instances, they are induced exogenously; for example, by contaminated silage affecting primarily the conjunctiva, cornea, or the anterior chamber. Sporadic infections as well as outbreaks have been described. In humans, besides exogenous infections, endogenous infections also occur, inducing mainly endophthalmitis. Since an exact diagnosis of the causative agent is often delayed, specific therapy starts too late, so that the outcome is often poor. The antibiotics of primary choice would be ampicillin or a quinolone such as moxifloxacin or levofloxacin. The role of fosfomycin for therapy of ocular infections is discussed.

  1. Billie's eyes.

    PubMed

    Dunning, S E

    1993-03-01

    The author, a nurse, is personally opposed to abortion; however, her earlier encounter with a victim of an illegal abortion has prevented her from joining campaigns to reinstate bans on abortion rights. The woman, "Billie," presented to an inner-city Chicago hospital in 1970 with hemorrhaging. She had delayed going for treatment because she feared being imprisoned for having obtained an abortion. She rapidly entered septic shock, with hypotension, confusion, and hallucinations. Physicians removed her infected uterus and ovaries. Subsequent kidney failure necessitated the transfer of this young woman to another hospital where she could receive dialysis. The author was unable to obtain follow-up information on whether Billie survived. She remains haunted by the memory of Billie's wide, frightened eyes as she was placed in the ambulance. It is this memory, and the knowledge that desperate women like Billie will find someone, somewhere to perform an illegal abortion, that is behind the author's reluctant support for the right to choose.

  2. Contact lenses in extreme cold environments: response of rabbit corneas.

    PubMed

    Socks, J F

    1982-04-01

    Contact lenses are worn by many individuals in military and civilian populations. Anecdotal reports have described contact lenses "sticking" and "freezing" to the eye during extreme cold conditions. However, some articles indicate the advantages of wearing contact lenses in cold environments. Military operations frequently taken place in cold regions; therefore, we need to known whether contact lenses can be worn safely in extreme cold. Rabbits were fitted with hard (polymethyl methacrylate) contact lenses and exposed to -28.9 degrees C temperatures with winds up to 78 mph (125 km/hr) for 3-hr periods. The wind-chill factor in these conditions exceeded -67.8 degrees C. No effects of the cold or contact lenses were seen in 85% of the eyes. A few of the eyes, both with contact lenses and without, showed mild superficial fluorescein staining of the cornea which cleared within a few ours after exposure. Histologic examination of the corneas revealed no abnormalities attributable to the cold. Inasmuch as this study showed that rabbits wearing contact lenses in extreme cold suffered no acute deleterious effects to the eyes, the research can be expanded to include human subjects.

  3. Rabbit renotropic system

    SciTech Connect

    Areas, J.; Yun, G.C.; Rahmat, J.; Gersten, D.; Goel, R.; Preuss, H.G.

    1988-04-01

    Elevated levels of a specific renal growth factor, renotropin, have been associated with spontaneous hypertension. To examine this association more closely, we have undertaken the development of a better assay system to characterize and purify renotropin. Sera from rabbits prior to operation (control) and at a specified time after unilateral nephrectomy (uni) were examined for renotropic activity. Comparing the effects of uni to control sera in the same rabbit, significant stimulation of 3H-thymidine incorporation into the DNA of primary rabbit kidney cultures incubated in D-valine medium to eliminate fibroblast growth was noted: at 3 days postoperatively 73% (n = 13), at 7 days 103% (n = 39), at 10 days 130% (n = 31), at 21 days 101% (n = 24), at 42 days 89% (n = 13). All values were at least P less than 0.01. The stimulatory properties were dose-dependent but reached a plateau at high serum concentrations. Comparing CPM/mg protein in uni/control in different concentrations of sera 7 days postoperatively, uni versus control were 67/44 at 5% v/v, 139/72 at 10% v/v, 261/161 at 20% v/v, and 243/136 at 40% v/v. The renotropic effect of uni sera remained after dialysis in incubation medium and after sera were heated in boiling water for 5 minutes. Renal extracts obtained from growing kidneys 7 days postnephrectomy augmented renotropic activity. Atrial natriuretic factor, ouabain, PGF2 alpha, PGE1, and cAMP did not possess renotropic activity. We conclude that the primary rabbit kidney culture assay for renotropin is highly sensitive and will be an important tool to comprehend the role of renotropin in the pathogenesis of hypertension.

  4. Intrastromal Injection of China Painting Ink in Corneas of Male Rabbits: Clinical and Histological Study

    PubMed Central

    Alsmman Hassan, Alahmady Hamad; Abd Elhaliem Soliman, Nesreen Gamal-Eldeen

    2016-01-01

    Background. Many patients with corneal opacity or complicated cataract in blind eye ask for cosmoses. In this study we tried to investigate the staining of corneas of male rabbits by Rotring China painting ink and to study the histological changes. Method. 10 eyes of 10 male Baladi Egyptian rabbits were injected (0.1 mL) intrastromally in the cornea by the use of China painting ink (Rotring Tinta China) through insulin syringe (27-gauge needle) by single injection; clinical follow-up is for 6 months and lastly the rabbits were scarified and the stained eyes were enucleated for histological analysis. Results. Clinically the stain was stable in color and distribution in corneas with no major complications. Histological results of the stained rabbit corneas showed blackish pigmentation in the corneal stroma without any inflammatory cellular infiltration. Some fibroblast cells had pigment granules in their cytoplasm in the adjacent layers. Conclusion. Corneal staining by China painting ink is effective and safe in staining of male rabbits cornea; however further study in human corneas with longer follow-up period is advisable. PMID:27195146

  5. Pharmacokinetics, Electrophysiological, and Morphological Effects of the Intravitreal Injection of Mycophenolic Acid in Rabbits

    PubMed Central

    Gasparin, Fabio; Aguiar, Renata Genaro; Ioshimoto, Gabriela Lourençon; Silva-Cunha, Armando; Fialho, Silvia Ligório; Liber, André Mauricio; Nagy, Balázs Vince; Oiwa, Nestor Norio; Costa, Marcelo Fernandes; Joselevitch, Christina; Ventura, Dora Fix

    2014-01-01

    Abstract Purpose: To determine the half-life of mycophenolic acid (MPA) in the vitreous of New Zealand albino rabbits after intravitreal injection and the retinal toxicity of different doses of MPA. Methods: Ten micrograms of MPA (Roche Bioscience, Palo Alto, CA) was injected in the vitreous of 16 rabbits, animals were sacrificed at different time-points, and vitreous samples underwent high-performance liquid chromatography. For functional and morphological studies, 5 doses of MPA (0.05, 0.5, 2, 10, and 100 μg) were injected in the vitreous of 20 rabbits. As control, contralateral eyes were injected with aqueous vehicle. Electroretinograms (ERGs) were recorded before injection and at days 7, 15, and 30. Animals were sacrificed on day 30 and retinas were analyzed under light microscopy. Results: MPA half-life in the vitreous was 5.0±0.3 days. ERG revealed photoreceptor functional impairment in eyes injected with 0.5 μg and higher on day 30, while eyes injected with 100 μg presented the same changes already from day 15. No morphological change was found. Conclusions: MPA vitreous half-life is 5.0 days. Intravitreal injection of 0.5 μg MPA and higher causes dose- and time-related photoreceptor sensitivity decrease in rabbits. The MPA dose of 0.05 μg may be safe for intravitreal use in rabbits. PMID:24828287

  6. Ex vivo cultivation of corneal limbal epithelial cells in a thermoreversible polymer (Mebiol Gel) and their transplantation in rabbits: an animal model.

    PubMed

    Sitalakshmi, G; Sudha, B; Madhavan, H N; Vinay, S; Krishnakumar, S; Mori, Yuichi; Yoshioka, Hiroshi; Abraham, Samuel

    2009-02-01

    We evaluated the efficacy of autologous expanded corneal epithelial cell transplants derived from harvested limbal biopsy cultured on a thermoreversible polymer (Mebiol Gel) for the management of unilateral limbal stem cell deficiency (LSCD). Corneal limbal biopsies from 12 rabbits were cultured on a thermoreversible polymer Mebiol Gel at 37 degrees C. Cells were harvested from the dishes after 3 weeks by reducing temperature to 4 degrees C. Autologous transplantation was undertaken to reconstruct the experimentally induced limbal stem cell deficiency in the rabbit eyes. The corneas of both eyes of all rabbits were harvested later for molecular studies. Reparative surgery was a total success in seven rabbits, partial success in two, and failure in three eyes. Histology of the seven successful eyes showed the successful growth of the corneal epithelium. Immunohistochemistry and reverse transcriptase polymerase chain reaction showed the cornea phenotype and stem cell-associated markers in the limbus of the seven successful eyes, indicating the homing of these cells into limbus. In the three failure cases and in the two control rabbit eyes, used in the study, histology showed presence of goblet cells and vascularization in the stroma with abortive formation of corneal epithelium. Our results suggest that transplantation of autologous limbal epithelial cells grown in thermoreversible polymer Mebiol Gel may restore a nearly normal ocular epithelial surface in eyes with unilateral LSCD.

  7. Palisade Endings Are a Constant Feature in the Extraocular Muscles of Frontal-Eyed, But Not Lateral-Eyed, Animals

    PubMed Central

    Blumer, Roland; Maurer-Gesek, Barbara; Gesslbauer, Bernhard; Blumer, Michael; Pechriggl, Elisabeth; Davis-López de Carrizosa, María A.; Horn, Anja K.; May, Paul J.; Streicher, Johannes; de la Cruz, Rosa R.; Pastor, Ángel M.

    2016-01-01

    Purpose To test whether palisade endings are a general feature of mammalian extraocular muscles (EOMs). Methods Thirteen species, some frontal-eyed (human, monkey, cat, and ferret), and others lateral-eyed (pig, sheep, calf, horse, rabbit, rat, mouse, gerbil, and guinea pig) were analyzed. Palisade endings were labeled by using different combinations of immunofluorescence techniques. Three-dimensional reconstructions of immunolabeled palisade endings were done. Results In all frontal-eyed species, palisade endings were a consistent feature in the rectus EOMs. Their total number was high and they exhibited an EOM-specific distribution. In particular, the number of palisade endings in the medial recti was significantly higher than in the other rectus muscles. In the lateral-eyed animals, palisade endings were infrequent and, when present, their total number was rather low. They were only found in ungulates (sheep, calf, pig, and horse) and in rabbit. In rodents (rat, guinea pig, mouse, and gerbil) palisade endings were found infrequently (e.g., rat) or were completely absent. Palisade endings in frontal-eyed species and in some lateral-eyed species (pig, sheep, calf, and horse) had a uniform morphology. They generally lacked α-bungarotoxin staining, with a few exceptions in primates. Palisade endings in other lateral-eyed species (rabbit and rat) exhibited a simplified morphology and bound α-bungarotoxin. Conclusions Palisade endings are not a universal feature of mammalian EOMs. So, if they are proprioceptors, not all species require them. Because in frontal-eyed species, the medial rectus muscle has the highest number of palisade endings, they likely play a special role in convergence. PMID:26830369

  8. [The antiallergic eye drops "polynadyme": development, experimental and clinical studies].

    PubMed

    Maĭchuk, Iu F; Pozdniakov, V I; Pozdniakova, V V; Iakushina, L N

    2006-01-01

    The antiallergic eye drops "Polynadyme", proposed by the Helmgolz Moscow Research Institute of Eye Diseases, have been prepared by the "Sintez" PJSC (Kurgan). The drops exert a combination of antihistaminic and vasoconstrictive effects and, for better tolerability, contain a low-toxic preserving complex. The drops are polymer-based, which ensures a long action and an artificial tear effect. Preclinical rabbit trials have shown the safety of the "Polynadyme" eye drops, their specific activity in preventing an allergic reaction, and their antiallergic effect on a model of allergic conjunctivitis. Comparative clinical trials covering 150 patients have yielded excellent and good results in 93% of cases. In acute allergic reactions, hyperemia, itch, and burning diminished just 5 minutes after administration. The "Polynadyme" eye drops are effective in treating pollinous conjunctivitis, spring (vernal) keratoconjunctivitis, allergic reactions when wearing contact lenses, the dry eye syndrome, drug-induced and toxicoallergic conjunctivitis, and other ocular allergic reactions.

  9. Eye Injuries (For Parents)

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old Eye Injuries KidsHealth > For Parents > Eye Injuries Print A ... sand, dirt, and other foreign bodies on the eye surface) Wash your hands thoroughly before touching the ...

  10. Diabetes - eye care

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000078.htm Diabetes - eye care To use the sharing features on this ... prevent them from getting worse. You Need Regular eye Exams Every year, you should have an eye ...

  11. Eye muscle repair - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100062.htm Eye muscle repair - series—Normal anatomy To use the sharing ... the eyeball to the eye socket. The external muscles of the eye are found behind the conjunctiva. ...

  12. Eye Cosmetic Safety

    MedlinePlus

    ... when they are new. FDA has an Import Alert in effect for cosmetics -- including eye cosmetics -- contaminated ... in the area of the eye. An import alert for cosmetics containing illegal colors lists several eye ...

  13. Dilating Eye Drops

    MedlinePlus

    ... sometimes used to treat eye diseases, such as amblyopia and inflammation. How long do dilating drops last? ... used to treat certain eye diseases, such as amblyopia and inflammation in the eye. These therapeutic dilating ...

  14. Regulatory T cells are decreased in acute RHDV lethal infection of adult rabbits.

    PubMed

    Teixeira, Luzia; Marques, Raquel M; Aguas, Artur P; Ferreira, Paula G

    2012-08-15

    Rabbit hemorrhagic disease virus (RHDV) is the etiologic agent of rabbit hemorrhagic disease (RHD), an acute lethal infection that kills 90% of adult rabbits due to severe acute liver inflammation. Interestingly, young rabbits are naturally resistant to RHDV infection. Here, we have compared naturally occurring CD4(+)Foxp3(+) regulatory T cells (Tregs) between young and adult rabbits after infection by RHDV. The number and frequency of Tregs was decreased in the spleen of adult rabbits 24h after the RHDV infection; this was in contrast with the unchanged number and frequency of splenic Tregs found in young rabbits after the same infection. Also, serum levels of IL-10 and TGF-β were enhanced in the infected adult rabbits whereas no alteration was observed in infected young rabbits. However, this increase is accompanied by a burst of pro-inflammatory cytokines, but seems not able to prevent the death of the animals with severe acute liver inflammation in few days after infection. Since Tregs downregulate inflammation, we conclude that their decrease may contribute to the natural susceptibility of adult rabbits to RHDV infection. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. HEREDITARY PREMATURE SENESCENCE OF THE RABBIT

    PubMed Central

    Pearce, Louise; Brown, Wade H.

    1960-01-01

    The occurrence of hereditary premature senescence in a family of pure bred Belgian hares belonging to a rabbit-breeding colony organized for the investigation of constitutional problems, has been described. Representatives of 20 generations of the complex have been studied. The condition was a degeneration of variable degrees of severity and two principal forms were recognized, the acute and the chronic, the chronic being the more frequent. The chronic form has now been described in terms of the principal local or external manifestations; that is, degeneration of the coat and skin, lesions of the eyes and feet, and reproductive abnormalities, and of the general deterioration which in severe cases pursued a progressive course characterized by muscle wasting, fat reduction, emaciation, weakness, and death. The acute form will be described in the next paper (2). PMID:13733754

  16. In the eye of the beholder: a survey of models for eyes and gaze.

    PubMed

    Hansen, Dan Witzner; Ji, Qiang

    2010-03-01

    Despite active research and significant progress in the last 30 years, eye detection and tracking remains challenging due to the individuality of eyes, occlusion, variability in scale, location, and light conditions. Data on eye location and details of eye movements have numerous applications and are essential in face detection, biometric identification, and particular human-computer interaction tasks. This paper reviews current progress and state of the art in video-based eye detection and tracking in order to identify promising techniques as well as issues to be further addressed. We present a detailed review of recent eye models and techniques for eye detection and tracking. We also survey methods for gaze estimation and compare them based on their geometric properties and reported accuracies. This review shows that, despite their apparent simplicity, the development of a general eye detection technique involves addressing many challenges, requires further theoretical developments, and is consequently of interest to many other domains problems in computer vision and beyond.

  17. Low-Level Primary Blast Causes Acute Ocular Trauma in Rabbits.

    PubMed

    Jones, Kirstin; Choi, Jae-Hyek; Sponsel, William E; Gray, Walt; Groth, Sylvia L; Glickman, Randolph D; Lund, Brian J; Reilly, Matthew A

    2016-07-01

    The objective of this study was to determine whether clinically significant ocular trauma can be induced by a survivable isolated primary blast using a live animal model. Both eyes of 18 Dutch Belted rabbits were exposed to various survivable low-level blast overpressures in a large-scale shock tube simulating a primary blast similar to an improvised explosive device. Eyes of the blast-exposed rabbits (as well as five control rabbits) were thoroughly examined before and after blast to detect changes. Clinically significant changes in corneal thickness arose immediately after blast and were sustained through 48 h, suggesting possible disruption of endothelial function. Retinal thickness (RT) increased with increasing specific impulse immediately after exposure. Intraocular pressure (IOP) was inversely correlated with the specific impulse of the blast wave. These findings clearly indicate that survivable primary blast causes ocular injuries with likely visual functional sequelae of clinical and military relevance.

  18. Therapeutic efficiency of tissue-engineered human corneal endothelium transplants on rabbit primary corneal endotheliopathy.

    PubMed

    Fan, Ting-jun; Zhao, Jun; Hu, Xiu-zhong; Ma, Xi-ya; Zhang, Wen-bo; Yang, Chao-zhong

    2011-06-01

    To evaluate the therapeutic efficiency of tissue-engineered human corneal endothelia (TE-HCEs) on rabbit primary corneal endotheliopathy (PCEP), TE-HCEs reconstructed with monoclonal human corneal endothelial cells (mcHCECs) and modified denuded amniotic membranes (mdAMs) were transplanted into PCEP models of New Zealand white rabbits using penetrating keratoplasty. The TE-HCEs were examined using diverse techniques including slit-lamp biomicroscopy observation and pachymeter and tonometer measurements in vivo, and fluorescent microscopy, alizarin red staining, paraffin sectioning, scanning and transmission electron microscopy observations in vitro. The corneas of transplanted eyes maintained transparency for as long as 200 d without obvious edema or immune rejection. The corneal thickness of transplanted eyes decreased gradually after transplanting, reaching almost the thickness of normal eyes after 156 d, while the TE-HCE non-transplanted eyes were turbid and showed obvious corneal edema. The polygonal corneal endothelial cells in the transplanted area originated from the TE-HCE transplant. An intact monolayer corneal endothelium had been reconstructed with the morphology, cell density and structure similar to those of normal rabbit corneal endothelium. In conclusion, the transplanted TE-HCE can reconstruct the integrality of corneal endothelium and restore corneal transparency and thickness in PCEP rabbits. The TE-HCE functions normally as an endothelial barrier and pump and promises to be an equivalent of HCE for clinical therapy of human PCEP.

  19. [The effect of gamma rays on glutathion and ascorbic acid content in rabbit lenses (author's transl)].

    PubMed

    Zygulska-Mach, H; Mach, Z

    1975-01-01

    It is pointed out that the partner non radiated eye is also influenced after employment of high radiation on an eye. The authors radiated rabbit eyes with gamma rays employing Stallard-applicators and determined the glutathion and ascorbic acid content in the lenses. The lenses of the partner eye were also examined for comparison. In those eyes which were directly radiated there was a fall of concentration of the two substances indirectly proportional to the dose of rays employed. In the partner eyes which were not directly subjected to direct radiation there were changes of similar character which were however not so much pronounced. The role of glutathion and ascorbic acid in lens metabolism is pointed out.

  20. Eyeing Ganymede

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Jupiter casts a baleful eye toward the moon Ganymede in this enhanced-contrast image from NASA's Cassini spacecraft.

    Jupiter's 'eye', the Great Red Spot, was captured just before disappearing around the eastern edge of the planet. The furrowed eyebrow above and to the left of the spot is a turbulent wake region caused by westward flow that has been deflected to the north and around the Red Spot. The smallest features visible are about 240 kilometers (150 miles) across.

    Within the band south of the Red Spot are a trio of white ovals, high pressure counterclockwise-rotating regions that are dynamically similar to the Red Spot. The dark filamentary features interspersed between white ovals are probably cyclonic circulations and, unlike the ovals, are rotating clockwise.

    Jupiter's equatorial zone stretching across the planet north of the Spot appears bright white, with gigantic plume clouds spreading out from the equator both to the northeast and to the southeast in a chevron pattern. This zone looks distinctly different than it did during the Voyager flyby 21 years ago. Then, its color was predominantly brown and the only white plumes conspicuous against the darker material beneath them were oriented southwest-to-northeast.

    Ganymede is Jupiter's largest moon, about 50 percent larger than our own Moon and larger than the planet Mercury. The visible details in this image are different geological terrains. Dark areas tend to be older and heavily cratered; brighter areas are younger and less cratered. Cassini images of Ganymede and Jupiter's other large moons taken near closest approach on Dec. 30 will have resolutions about four times better than that seen here.

    This image is a color composite of ones taken with different filters by Cassini's narrow-angle camera on Nov. 18, 2000, processed to enhance contrast. Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of

  1. Cat's Eye Nebula

    NASA Image and Video Library

    2017-09-27

    The Cat's Eye Nebula, one of the first planetary nebulae discovered, also has one of the most complex forms known to this kind of nebula. Eleven rings, or shells, of gas make up the Cat's Eye. The full beauty of the Cat's Eye Nebula is revealed in this detailed view from NASA's Hubble Space Telescope. The image from Hubble's Advanced Camera for Surveys (ACS) shows a bull's eye pattern of eleven or even more concentric rings, or shells, around the Cat's Eye. Each 'ring' is actually the edge of a spherical bubble seen projected onto the sky -- that's why it appears bright along its outer edge. Observations suggest the star ejected its mass in a series of pulses at 1,500-year intervals. These convulsions created dust shells, each of which contain as much mass as all of the planets in our solar system combined (still only one percent of the Sun's mass). These concentric shells make a layered, onion-skin structure around the dying star. The view from Hubble is like seeing an onion cut in half, where each skin layer is discernible. The bull's-eye patterns seen around planetary nebulae come as a surprise to astronomers because they had no expectation that episodes of mass loss at the end of stellar lives would repeat every 1,500 years. Several explanations have been proposed, including cycles of magnetic activity somewhat similar to our own Sun's sunspot cycle, the action of companion stars orbiting around the dying star, and stellar pulsations. Another school of thought is that the material is ejected smoothly from the star, and the rings are created later on due to formation of waves in the outflowing material. Credit: NASA, ESA, HEIC, and The Hubble Heritage Team (STScI/AURA) Acknowledgment: R. Corradi (Isaac Newton Group of Telescopes, Spain) and Z. Tsvetanov (NASA) The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science

  2. Lens extraction with ultrasound. Experiments in rabbits.

    PubMed Central

    Clarkson, D M; Phillips, C I

    1976-01-01

    The extraction of the rabbit lens is described using a 25 G irrigating needle and a 22 G aspirating needle; at the latter's bevelled tip lens fragmentation occurs due to the longitudinal ultrasonic vibrations generated there--an 'acoustic horn' causes the tip to vibrate with large amplitudes. The use of small needles allows considerable manoeuvrability in the anterior chamber and usually eliminates the need for corneal suturing. Push-pull coupled syringes equate the volume of irrigation with that of aspiration. This procedure makes possible lens extraction through an aperture in the anterior capsule of the rabbit's lens and a similar machine is being constructed for trial on human cataract. Images PMID:1009054

  3. HEREDITARY DISTAL FORELEG CURVATURE IN THE RABBIT

    PubMed Central

    Pearce, Louise

    1960-01-01

    An inwardly directed curvature of the distal segment of both forelegs of the rabbit has been described. The condition was detected at 2 to 3 weeks of age, developed rapidly, and reached its final and permanent stage at 2 to 3 months of age. Only the distal epiphysis of the ulna was primarily affected and this in the form of a massive chondrodystrophic lesion accompanied by a progressive curvature of the shaft. The curvature of the growing radius was a secondary effect due to the firm, immovable, anatomical connection of the ulna and radius. The positional changes of the wrist and paw were likewise effects secondary to the changed form of the ulna and radius. The bowing abnormality occurred only in certain families of pure bred Beveren, Belgian, French Silver, and Dutch rabbits and was found to be inherited. The mode of inheritance was on the basis of a single recessive unit factor (5). PMID:13733755

  4. HEREDITARY PREMATURE SENESCENCE OF THE RABBIT

    PubMed Central

    Pearce, Louise; Brown, Wade H.

    1960-01-01

    The acute form of hereditary premature senescence in 79 rabbits, among which the 20th generation of the condition was represented, has been described. The manifestations did not differ in kind from those previously described in connection with the chronic form (1) of the complex but their degree and, in particular, the severity and the rate of progression of systemic degeneration were much greater. The rabbits either did not survive to 2 years 6 months, of age or their physical condition had become critical by this time. A senile appearance, largely due to deteriorative changes of the coat, was frequently observed. The essential nature of the senescence condition was obviously a degeneration and one in which vital mechanisms essential to the maintenance of health were involved. PMID:13733753

  5. Evaluation of ocular hazards due to electric arc flash at an in-line switch.

    PubMed

    Chou, B R; Cullen, A P

    1991-10-01

    We investigated the ocular damage resulting from operation of a solid blade pole-mounted in-line electrical switch at between 16 and 17 kV with current loads between 38 A and 340 A. Spectroradiometric data for the electric arcs produced as the switch was opened were obtained over the waveband 200 to 1500 nm. The eyes of adult pigmented rabbits were exposed to the arc flash at a distance of 2 m. The ocular tissues were assessed clinically and histologically up to 48 h postexposure. Threshold damage was clinically detectable only in eyes exposed to a 340 A arc. We conclude that at the normal current loads on a 17-kV electric power transmission line, the principal oculovisual hazards are due to molten metal fulminated from the switch by the arc, and after-images due to the bright visible light flash. At a working distance of 2 m, the ultraviolet ocular hazard is negligible. Adequate eye protection is provided by clear polycarbonate safety lenses.

  6. Michelangelo's eye disease.

    PubMed

    Gallenga, P E; Neri, Giampiero; D'Anastasio, Ruggero; Pettorrossi, Vito Enrico; Alfieri, Emilio; Capasso, Luigi

    2012-06-01

    Charged by the Pope Julius II for painting the Cappella Sistina in Rome (between 1508 and 1512), Michelangelo worked in an elevated scaffolding, in an anomalous position with dyes (including poisoning lead salts) and solvents (such as toxic turpentine) dripping on his face and continuously inhaling, in a dim environment illuminated only with oil lamps and candles, as he described himself and sketched in a sonet addressed to Giovanni da Pistoia. In 1510 he began suffering from eye disease: the main symptom was the necessity to elevate the document he was reading up to the level of his eyes. This defect disappeared few months after he finished painting his masterpiece. We hypothesize that the Michelangelo's eyes disease was a form of acquired and transitory nystagmus induced by the many hours he spent in up gaze, with a skew deviation, a form of ocular tilt reaction resulting from the impairment of spatial sensitivity (inversion illusion) due to the persistence of the artist's head in a horizontal position, looking upward. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Schizophrenia and the eye

    PubMed Central

    Silverstein, Steven M.; Rosen, Richard

    2015-01-01

    Although visual processing impairments are common in schizophrenia, it is not clear to what extent these originate in the eye vs. the brain. This review highlights potential contributions, from the retina and other structures of the eye, tovisual processing impairments in schizophrenia and high-risk states. A second goal is to evaluate the status of retinal abnormalities as biomarkers for schizophrenia. The review was motivated by known retinal changes in other disorders (e.g., Parkinson's disease, multiple sclerosis), and their relationships to perceptual and cognitive impairments, and disease progression therein. The evidence reviewed suggests two major conclusions. One is that there are multiple structural and functional disturbances of the eye in schizophrenia, all of which could be factors in the visual disturbances of patients. These include retinal venule widening, retinal nerve fiber layer thinning, dopaminergic abnormalities, abnormal ouput of retinal cells as measured by electroretinography (ERG), maculopathies and retinopathies, cataracts, poor acuity, and strabismus. Some of these are likely to be illness-related, whereas others may be due to medication or comorbid conditions. The second conclusion is that certain retinal findings can serve as biomarkers of neural pathology, and disease progression, in schizophrenia. The strongest evidence for this to date involves findings of widened retinal venules, thinning of the retinal nerve fiber layer, and abnormal ERG amplitudes. These data suggest that a greater understanding of the contribution of retinal and other ocular pathology to the visual and cognitive disturbances of schizophrenia is warranted, and that retinal changes have untapped clinical utility. PMID:26345525

  8. First field trial of a transmissible recombinant vaccine against myxomatosis and rabbit hemorrhagic disease.

    PubMed

    Torres, J M; Sánchez, C; Ramírez, M A; Morales, M; Bárcena, J; Ferrer, J; Espuña, E; Pagès-Manté, A; Sánchez-Vizcaíno, J M

    2001-08-14

    As a novel approach for immunisation of wild rabbits, we have recently developed a transmissible vaccine against myxomatosis and rabbit hemorrhagic disease (RHD) based on a recombinant myxoma virus (MV) expressing the RHDV capsid protein [J. Virol. 74 (2000) 1114]. The efficacy and safety of the vaccine have been extensively evaluated under laboratory conditions. In this study, we report the first limited field trial of the candidate vaccine that was undertaken in an island of 34 Has containing a population of around 300 rabbits. Following administration by the subcutaneous route to 76 rabbits, the vaccine induced specific antibody responses against both myxomatosis and RHDV in all the inoculated rabbits. Furthermore, the recombinant virus exhibited a limited horizontal transmission capacity, promoting seroconversion of around 50% of the uninoculated rabbit population. No evidence of undesirable effects due to the recombinant virus field release was detected.

  9. Dietary cholesterol modulates the excitability of rabbit hippocampal CA1 pyramidal neurons.

    PubMed

    Wang, Desheng; Schreurs, Bernard G

    2010-08-02

    Previous work has shown high dietary cholesterol can affect learning and memory including rabbit eyeblink conditioning and this effect may be due to increased membrane cholesterol and enhanced hippocampal amyloid beta production. This study investigated whether dietary cholesterol modulates rabbit hippocampal CA1 neuron membrane properties known to be involved in rabbit eyeblink conditioning. Whole-cell current clamp recordings in hippocampal neurons from rabbits fed 2 percent cholesterol or normal chow for 8 weeks revealed changes including decreased after-hyperpolarization amplitudes (AHPs) - an index of membrane excitability shown to be important for rabbit eyeblink conditioning. This index was reversed by adding copper to drinking water - a dietary manipulation that can retard rabbit eyeblink conditioning. Evidence of cholesterol effects on membrane excitability was provided by application of methyl-beta-cyclodextrin, a compound that reduces membrane cholesterol, which increased the excitability of hippocampal CA1 neurons.

  10. Penetration of new azole compounds into the eye and efficacy in experimental Candida endophthalmitis.

    PubMed Central

    Savani, D V; Perfect, J R; Cobo, L M; Durack, D T

    1987-01-01

    We studied the penetration of three azole compounds, ketoconazole, itraconazole, and fluconazole, into the ocular tissues and fluids of rabbits in the presence and absence of ocular inflammation. Drug concentrations were compared with those found in serum and cerebrospinal fluid. The rank order of penetration into eye tissue was fluconazole greater than ketoconazole greater than itraconazole. Fluconazole penetrated freely into both inflamed and uninflamed eyes. The presence of inflammation improved penetration of all three compounds into ocular fluids and tissues. Penetration of these azoles into the anterior chamber of uninflamed eyes and into the cerebrospinal fluid was similar. All three azole compounds reduced the number of yeasts found in the eye in hematogenous Candida albicans endophthalmitis in rabbits when therapy was initiated within 24 h of inoculation. However, only ketoconazole significantly reduced yeast counts in the eye when therapy was postponed for 7 days. PMID:3032091

  11. [Study of cytotoxic and antiviral effects of some eye drops].

    PubMed

    Dediulescu, Lucreţia; Dediulescu, Daniela Florentina

    2008-01-01

    The study of the cytotoxic and antiviral effect of six commercial mixtures, eye drops type, underlined the advantages of using eye drops with Indomethacin for Herpetic Keratitis, due to the antiviral effect and also for the lack of cytotoxicity.

  12. Distinguishing postganglionic from preganglionic lesions. Studies in rabbits with surgically produced Horner's syndrome.

    PubMed

    Skarf, B; Czarnecki, J S

    1982-08-01

    It has been suggested that the pupillary response to hydroxyamphetamine hydrobromide eyedrops will separate distal from proximal lesions of the sympathetic pathway from the brain to the eye (the pupil fails to dilate in postganglionic lesions). We studied the pupillary response to hydroxyamphetamine in two groups of rabbits with surgically produced Horner's syndrome. Rabbits in one group had postganglionic lesions. In all animals, a miotic pupil developed ipsilateral to the surgical lesion, and oculosympathetic paresis was confirmed in each by testing pupillary response to topically applied cocaine. In rabbits with postganglionic lesions, hydroxyamphetamine failed to dilate the miotic (Horner's) pupils as well as it dilated the normal pupils, while in rabbits with preganglionic lesions both miotic and normal pupils dilated equally. Hydroxyamphetamine appears to be a diagnostically useful drug in Horner's syndrome.

  13. Use of infrared thermography to assess the influence of high environmental temperature on rabbits.

    PubMed

    de Lima, V; Piles, M; Rafel, O; López-Béjar, M; Ramón, J; Velarde, A; Dalmau, A

    2013-10-01

    The aim of this work was to ascertain if infrared thermography (IRT) can be used on rabbits to assess differences in surface body temperature when they are subjected to two different environmental temperatures outside the comfort zone. Rabbits housed in room A were maintained at a temperature of below 30°C and rabbits in room B at a temperature of above 32°C for a year. Faeces were collected six times during the year to assess stress by means of faecal cortisol metabolites (FCM). The assessment of IRT was carried out to assess maximum and minimum temperatures on the eyes, nose and ears. FCM concentration was higher in room B than A, to confirm that stress conditions were higher in room B. Significant differences in IRT were found between the animals housed in both rooms. It was observed that it was more difficult for animals from room B to maintain a regular heat loss. Although all the body zones used to assess temperature with IRT gave statistical differences, the correlations found between the eyes, nose and ears were moderate, suggesting that they were giving different information. In addition, differences up to 3.36°C were found in the eye temperature of rabbits housed in the same room, with a clear effect of their position in relation to extractors and heating equipments. Therefore, IRT could be a good tool to assess heat stress in animals housed on typical rabbit farm buildings, giving a measure of how the animal is perceiving a combination of humidity, temperature and ventilation. Some face areas were better for analysing images. Minimum temperature on eyes and temperatures on nose are suggested to assess heat losses and critical areas of the farm for heat stress in rabbits.

  14. Development of a microarray chip for gene expression in rabbit ocular research.

    PubMed

    Popp, Michael P; Liu, Li; Timmers, Adrian; Esson, Douglas W; Shiroma, Lineu; Meyers, Craig; Berceli, Scott; Tao, Ming; Wistow, Graeme; Schultz, Gregory S; Sherwood, Mark B

    2007-02-02

    To develop a microarray for the rabbit that can be used for ocular gene expression research. Messenger RNA was isolated from anterior segment tissues (cornea, conjunctiva, and iris) and posterior segment tissues (lens, retina, and sclera) of rabbit eyes and used to create two independent cDNA libraries through the NEIBank project. Clones from each of these libraries were sequenced from both the 5' and 3' ends. These sequences and those from the National Center for Biotechnology Information (NCBI) taxonomy database for rabbit were combined and electronically assembled into a set of unique nonoverlapping continuous sequences (contigs). For each contig, a homology search was performed using BLASTX and BLASTN against both the NCBI NR and NT databases to provide gene annotation. Unique contigs were sent to Agilent Technologies, where 60 base oligonucleotide probes were designed and synthesized, in situ, on two different arrays in an 8 array x 1900 element format. Glaucoma filtration surgery was performed on one eye of six rabbits. After 14 days, tissue was harvested from the conjunctiva and Tenon's capsule of both the surgically treated and untreated control eyes. Total RNA from each sample was labeled with cyanine dyes and hybridized to our custom microarrays. Of the 3,154 total probes present on the two arrays, 2,522 had a signal value above the background. The expression of 315 genes was significantly altered by glaucoma filtration surgery. Genes whose expression was altered included proteins associated with inflammatory response, defense response, and proteins involved in synthesis of the extracellular matrix. The results of this rabbit microarray study are consistent with those from other wound healing studies, indicating that this array can provide valid information on broad patterns of gene expression. This is the first microarray available for rabbit studies and is a valuable tool that can be used to study molecular events in the eye.

  15. Analysis of immediate changes of water-soluble metabolites in alkali-burned rabbit cornea, aqueous humor and lens by high-resolution 1H-NMR spectroscopy.

    PubMed

    Risa, Oystein; Saether, Oddbjørn; Midelfart, Anna; Krane, Jostein; Cejková, Jitka

    2002-01-01

    To investigate immediate changes in water-soluble metabolites of ocular tissue in alkali-burned eyes by using high-resolution 1H-NMR spectroscopy. Adult New Zealand rabbit eyes were burned with 1 M NaOH for 1 min. Normal eyes were used as control. Samples from aqueous humor and perchloric acid extracts of the cornea and lens were analyzed on a NMR spectrometer operating at 500 MHz for protons. Metabolites were quantified by comparing peak area with an added internal standard, TSP (3'-trimethylsilylpropinate-2,2,3,3-d4). Alkali burn of corneal surface causes immediate changes in concentration of many water-soluble metabolites in the anterior segment. Even as far away as the lens a significant increase in lactate was found. Cornea showed a significant increase in glucose and a significant decrease in hypo-taurine concentration. Most changes were observed in aqueous humor, with significant increases in succinate, creatine, scyllo- and myo-inositol and a significant decrease in citrate concentration. Furthermore, a small decrease in ascorbate concentration in aqueous humor was observed. The present study provides a valuable contribution to the knowledge of metabolic alterations in alkali-burned eyes. It shows that 1H-NMR spectroscopy is well suited for simultaneous qualitative and quantitative analysis of changes of metabolite concentrations in damaged tissues. This can help us to better evaluate and understand the biological alterations due to alkali burn.

  16. Rabbit lung after inhalation of hexa- and trivalent chromium.

    PubMed

    Johansson, A; Robertson, B; Curstedt, T; Camner, P

    1986-10-01

    Rabbits were exposed to aerosols of hexavalent (Na2CrO4) and trivalent chromium (Cr(NO3)3) at concentrations of 0.9 and 0.6 mg/m3 of chromium respectively for 4-6 weeks (5 days/week and 6 hr/day). Three of eight rabbits exposed to Cr(VI) and three of eight rabbits exposed to Cr(III) showed nodular accumulations of alveolar macrophages, similar to the lesions observed in previous experiments after exposure to Ni2+, Cd2+, or metallic nickel. Macrophages from rabbits exposed to Cr(III) usually contained round dark inclusions, large lysosomes, and laminated inclusions similar to the lamellar bodies in the type II cells, and most macrophages from rabbits exposed to Cr(VI) showed enlarged lysosomes. However, the total amount of phospholipids and the volume density of type II cells did not differ significantly between exposed rabbits and controls. Our findings indicate that the macrophages are directly affected by chromium. The accumulation of laminated structures in the alveolar macrophages after Cr(III) exposure might be due to an impaired catabolism of surfactant.

  17. STUDIES ON THE ETIOLOGY OF SPONTANEOUS CONJUNCTIVAL FOLLICULOSIS OF RABBITS

    PubMed Central

    Olitsky, Peter K.; Syverton, Jerome T.; Tyler, Joseph R.

    1934-01-01

    Spontaneous conjunctival folliculosis is widespread among various species of rabbits. It exists in two forms: Type I, in which the lesions are localized and the disease is relatively inactive, and Type II, in which the follicles are closely distributed over the entire surface of the conjunctivae and the affection is more active and characterized by extensive inflammatory reactions. One type can be converted into the other either by experimental methods or by natural processes. The disease can be transmitted from rabbit to rabbit by means of subconjunctival inoculation of suspensions of the affected tissues or by instillation of such material into the conjunctival sac, or even by mere contact of folliculosis animals with rabbits having smooth conjunctivae. It is plain that the disease is an infection. The causal agent of the infection is not filtrable through Seitz discs that retain Serratia marcescens nor through Berkefeld V candles that permit the passage of this organism. Furthermore, the lesions of the spontaneous or of the experimental disease do not exhibit the cytotropic effects or the inclusion bodies suggestive of the action of an ultramicroscopic virus. They are characterized, on the other hand, by a persistent and progressive chronicity and show certain resemblances to the granulomata. The evidence suggests that the spontaneous conjunctival folliculosis of rabbits is due to a microorganism—one having a low grade pathogenic action. In a paper shortly to be published, a bacterium capable of reproducing folliculosis in normal rabbits will be described. PMID:19870281

  18. Effect of non-steroidal anti-inflammatory drugs (NSAID) on the rabbit corneal epithelium studied by scanning electron microscopy.

    PubMed

    Stroobants, A; Fabre, K; Maudgal, P C

    2000-01-01

    We investigated the effect of 6 commercially available non-steroidal anti-inflammatory drug (NSAID) eye drops on the normal corneal epithelium of rabbits. Each drug was instilled into both eyes of 2 rabbits, 5 times a day, for 5 consecutive days. Two additional corneas of one rabbit, without any treatment, served as control. After treatment, the corneas were excised and processed for scanning electron microscopic evaluation. The epithelial changes induced by the drugs were graded by an empirical score system. All test compounds caused alterations in the cell membranes and surface microvilli, or even exfoliation and necrosis of surface cells. The extent of cell damage appeared to be related to the active ingredient in the eye drops, the pH of the solution, and the constituents of the vehicle, especially the type of preservative used.

  19. LASER BIOLOGY AND MEDICINE: A laser-spectroscopy system for fluorescent diagnostics and photodynamic therapy of diseases of eye retina and choroid

    NASA Astrophysics Data System (ADS)

    Meerovich, G. A.; Shevchik, S. A.; Loshchenov, M. V.; Budzinskaya, M. V.; Ermakova, N. A.; Kharnas, S. S.

    2002-11-01

    A laser-spectroscopy system for the fluorescent diagnostics and photodynamic therapy of pathologic eye-fundus changes combined with the use of the Photosens compound is developed. The system is tested on experimental animals (mice and rabbits).

  20. INFECTIOUS MYXOMATOSIS OF RABBITS

    PubMed Central

    Rivers, T. M.

    1930-01-01

    The virus of infectious myxomatosis of rabbits (Sanarelli) induces multiple lesions in the skin, lymph glands, tunica vaginalis,epididymis, testicle, spleen, and lungs. Growth and destruction of cells in the epidermis overlying the myxomatous masses leads to the formation of vesicles. Cytoplasmic inclusions are found in affected epidermal cells. Occasionally, similar inclusions are seen in other involved epithelial cells. The nature of the inclusions is an open question. In the myxomatous masses situated in the subcutaneous and other tissues, evidences of alteration and growth of certain cells are observed. PMID:19869741

  1. INFECTIOUS MYXOMATOSIS OF RABBITS

    PubMed Central

    Smadel, Joseph E.; Ward, S. M.; Rivers, Thomas M.

    1940-01-01

    A second soluble antigen, separable from the virus, occurs in extracts of infected skin and in the serum of rabbits acutely ill with infectious myxomatosis. Like the first antigen (A), the second (B) is heat labile and has certain characteristics of a globulin. The two antigens precipitate in different concentrations of ammonium sulfate and can be separated by this method. Neither of the antigens after being heated at 56°C. precipitates in the presence of specific antibody but each is capable of inhibiting the activity of its antibody. PMID:19871012

  2. The eye and the heart

    PubMed Central

    Flammer, Josef; Konieczka, Katarzyna; Bruno, Rosa M.; Virdis, Agostino; Flammer, Andreas J.; Taddei, Stefano

    2013-01-01

    The vasculature of the eye and the heart share several common characteristics. The easily accessible vessels of the eye are therefore—to some extent—a window to the heart. There is interplay between cardiovascular functions and risk factors and the occurrence and progression of many eye diseases. In particular, arteriovenous nipping, narrowing of retinal arteries, and the dilatation of retinal veins are important signs of increased cardiovascular risk. The pressure in the dilated veins is often markedly increased due to a dysregulation of venous outflow from the eye. Besides such morphological criteria, functional alterations might be even more relevant and may play an important role in future diagnostics. Via neurovascular coupling, flickering light dilates capillaries and small arterioles, thus inducing endothelium-dependent, flow-mediated dilation of larger retinal vessels. Risk factors for arteriosclerosis, such as dyslipidaemia, diabetes, or systemic hypertension, are also risk factors for eye diseases such as retinal arterial or retinal vein occlusions, cataracts, age-related macular degeneration, and increases in intraocular pressure (IOP). Functional alterations of blood flow are particularly relevant to the eye. The primary vascular dysregulation syndrome (PVD), which often includes systemic hypotension, is associated with disturbed autoregulation of ocular blood flow (OBF). Fluctuation of IOP on a high level or blood pressure on a low level leads to instable OBF and oxygen supply and therefore to oxidative stress, which is particularly involved in the pathogenesis of glaucomatous neuropathy. Vascular dysregulation also leads to a barrier dysfunction and thereby to small retinal haemorrhages. PMID:23401492

  3. Eating for Your Eyes

    ERIC Educational Resources Information Center

    Stastny, Sherri Nordstrom; Garden-Robinson, Julie

    2011-01-01

    An educational program targeting older adults was developed to increase knowledge regarding nutrition and eye health. With age, the chance for eye disease increases, so prevention is critical. The Eating for Your Eyes program has promoted behavior changes regarding eye health among the participants. This program is easily replicated and use is…

  4. Eating for Your Eyes

    ERIC Educational Resources Information Center

    Stastny, Sherri Nordstrom; Garden-Robinson, Julie

    2011-01-01

    An educational program targeting older adults was developed to increase knowledge regarding nutrition and eye health. With age, the chance for eye disease increases, so prevention is critical. The Eating for Your Eyes program has promoted behavior changes regarding eye health among the participants. This program is easily replicated and use is…

  5. Eye Injuries (For Parents)

    MedlinePlus

    ... the eye nausea or vomiting after an eye injury Think Prevention! Kids who play sports should wear protective goggles or unbreakable glasses as needed. Keep chemicals and other potentially dangerous objects out of the reach of children. Reviewed by: Steven Dowshen, ... (Conjunctivitis) Eyes Corneal Abrasions Styes Activity: Eyes ...

  6. Eye Injuries in Sports

    MedlinePlus

    ... and Fitness Sports Safety Eye Injuries in Sports Eye Injuries in Sports Exercise and FitnessPrevention and WellnessSports Safety Share Eye Injuries ... injury, detached retina, patient education, patient information, penetrating eye ... Exercise and Fitness, Prevention and Wellness, Sports Safety June ...

  7. Application of newly developed amniotic membrane ointment for photorefractive keratectomy in rabbits.

    PubMed

    Kim, Tae Hyun; Lee, Dong Yeoul; Rho, Jee Hyun; Rho, Sae Heun; Yoo, Kyung Won; Ahn, Hee Bae; Yoo, Young Hyun; Park, Woo Chan

    2006-01-01

    We developed amniotic membrane ointment (AMO), and the effect of instilling the AMO after photorefractive keratectomy (PRK) was investigated with respect to inflammatory cell infiltration into the corneal stroma, apoptosis of keratocytes, and suppression of lipid peroxidation of cellular walls. The PRK procedure was performed on both eyes of 10 white rabbits. One eye of each rabbit (the experimental eye) was instilled with the AMO and the other eye of the rabbit (the control eye) with a base ointment 0, 8 and 16 h after the PRK procedure. Corneal specimens were collected 24 h after the PRK procedure. Hematoxylin-eosin stain and TUNEL assay were conducted to demonstrate polymorphonuclear and apoptotic cells, respectively. To assess lipid peroxidation, immunohistochemical staining with an antibody to malondialdehyde was undertaken. Compared to the control, the cornea instilled with the AMO had significantly less polymorphonuclear cells infiltrating into the corneal stroma as well as keratocytes subjected to apoptosis. These corneas also showed a significantly less extent of lipid peroxidation than the control. These data support that instillation of the AMO effectively reduced the recruitment of polymorphonuclear cells, the induction of apoptosis in keratocytes, and lipid peroxidation induced by PRK. Thus, this study could provide basic data on the clinical application of the AMO in the days ahead.

  8. Assessing the systemic toxicity in rabbits after sub acute exposure to ocular irritant chemicals.

    PubMed

    Reshma, Cherian Sebastian; Sruthi, Sudhakaran; Syama, Santhakumar; Gayathri, Vishwanath; Mohanan, Parayanthala Valappil

    2015-03-01

    Eye is a highly vascularised organ. There are chances that a foreign substance can enter the systemic circulation through the eye and cause oxidative stress and evoke immune response. Here the eyes of rabbits were exposed, for a period of 7 days, to 5 known ocular irritants: Cetyl pyridinium chloride (CPC), sodium salicylate (SS), imidazole (IMI), acetaminophen (ACT) and nicotinamide (NIC). The eyes were scored according to the draize scoring. Blood collected from the treated rabbit were analyzed for haematological and biochemical parameters. After sacrifice, histological analysis of the eye and analysis of pro-inflammatory biomarkers (IL-1α, IL-1β, IL-8 and TNF-α) in the cornea using ELISA was carried out. Spleen was collected and the proliferation capacities of spleenocytes were analyzed. Liver and brain were collected and assessed for oxidative stress. The eye irritation potential of the chemicals was evident from the redness and swelling of the conjunctiva and cornea. Histopathological analysis and ELISA assay showed signs of inflammation in the eye. However, the haematological and biochemical parameters showed no change. Spleenocyte proliferations showed only slight alterations which were not significant. Also oxidative stress in the brain and liver were negligible. In conclusion, chemicals which cause ocular irritation and inflammation did not show any systemic side-effects in the present scenario.

  9. Intraocular pressure effects of water loading and venous compression tests in normal and denervated pigmented rabbits.

    PubMed

    Gual, A; Mintenig, G M; Belmonte, C

    1989-03-01

    We have compared IOP elevations induced by water-loading and by increased cephalic venous pressure in normal and denervated pigmented rabbits. Denervations were performed by sympathetic ganglionectomy and/or blockade of the sensory and autonomic innervation of the eye through retrobulbar anesthesia; retrobulbar anesthesia induced significant decreases of the basal IOP in control but not in ganglionectomized eyes. The water-loading test induced a peak pressure elevation approximately 30 min after water administration that could be counteracted by retrobulbar anesthesia. Ganglionectomized rabbits exhibited steeper IOP rises and greater IOP increases following water-loading than the control eyes; retrobulbar anesthesia in ganglionectomized eyes delayed the IOP response to water-loading. Compressions of the neck lasting 30 min elicited significant IOP elevations that were more pronounced in ganglionectomized eyes. In these eyes, retrobulbar anesthesia further increased the IOP rise elicited by neck compression. An IOP decrease below control values was observed at the end of the venous compression. The results indicate that an intact efferent innervation of the eye contributes to buffer IOP elevations induced by water-loading or cephalic venous stasis, presumably through the vascular effects of the ocular autonomic nerves.

  10. Pharmacokinetics and distributions of bevacizumab by intravitreal injection of bevacizumab-PLGA microspheres in rabbits

    PubMed Central

    Ye, Zhuo; Ji, Yan-Li; Ma, Xiang; Wen, Jian-Guo; Wei, Wei; Huang, Shu-Man

    2015-01-01

    AIM To investigate the pharmacokinetics and distributions of bevacizumab by intravitreal injection of prepared bevacizumab-poly (L-lactic-co-glycolic acid) (PLGA) microspheres in rabbits, to provide evidence for clinical application of this kind of bevacizumab sustained release dosage form. METHODS Bevacizumab was encapsulated into PLGA microsphere via the solid-in-oil-in-hydrophilic oil (S/O/hO) method. Fifteen healthy New Zealand albino-rabbits were used in experiments. The eyes of each rabbit received an intravitreal injection. The left eyes were injected with prepared bevacizumab-PLGA microspheres and the right eyes were injected with bevacizumab solution. After intravitreal injection, rabbits were randomly selected at days 3, 7, 14, 28 and 42 respectively, three animals each day. Then we used immunofluorescence staining to observe the distribution and duration of bevacizumab in rabbit eye tissues, and used the sandwich ELISA to quantify the concentration of free bevacizumab from the rabbit aqueous humor and vitreous after intravitreal injection. RESULTS The results show that the concentration of bevacizumab in vitreous and aqueous humor after administration of PLGA formulation was higher than that of bevacizumab solution. The T1/2 of intravitreal injection of bevacizumab-PLGA microspheres is 9.6d in vitreous and 10.2d in aqueous humor, and the T1/2 of intravitreal injection of soluble bevacizumab is 3.91d in vitreous and 4.1d in aqueous humor. There were statistical significant difference for comparison the results of the bevacizumab in vitreous and aqueous humor between the left and right eyes (P<0.05). The AUC0-t of the sustained release dosage form was 1-fold higher than that of the soluble form. The relative bioavailability was raised significantly. The immunofluorescence staining of PLGA-encapsulated bevacizumab (b-PLGA) in rabbit eye tissues was still observed up to 42d. It was longer than that of the soluble form. CONCLUSION The result of this study

  11. Rabbit haemorrhagic disease (RHD) and rabbit haemorrhagic disease virus (RHDV): a review

    PubMed Central

    2012-01-01

    Rabbit haemorrhagic disease virus (RHDV) is a calicivirus of the genus Lagovirus that causes rabbit haemorrhagic disease (RHD) in adult European rabbits (Oryctolagus cuniculus). First described in China in 1984, the virus rapidly spread worldwide and is nowadays considered as endemic in several countries. In Australia and New Zealand where rabbits are pests, RHDV was purposely introduced for rabbit biocontrol. Factors that may have precipitated RHD emergence remain unclear, but non-pathogenic strains seem to pre-date the appearance of the pathogenic strains suggesting a key role for the comprehension of the virus origins. All pathogenic strains are classified within one single serotype, but two subtypes are recognised, RHDV and RHDVa. RHD causes high mortality in both domestic and wild adult animals, with individuals succumbing between 48-72 h post-infection. No other species has been reported to be fatally susceptible to RHD. The disease is characterised by acute necrotising hepatitis, but haemorrhages may also be found in other organs, in particular the lungs, heart, and kidneys due to disseminated intravascular coagulation. Resistance to the disease might be explained in part by genetically determined absence or weak expression of attachment factors, but humoral immunity is also important. Disease control in rabbitries relies mainly on vaccination and biosecurity measures. Such measures are difficult to be implemented in wild populations. More recent research has indicated that RHDV might be used as a molecular tool for therapeutic applications. Although the study of RHDV and RHD has been hampered by the lack of an appropriate cell culture system for the virus, several aspects of the replication, epizootology, epidemiology and evolution have been disclosed. This review provides a broad coverage and description of the current knowledge on the disease and the virus. PMID:22325049

  12. Selenium-binding lactoferrin is taken into corneal epithelial cells by a receptor and prevents corneal damage in dry eye model animals.

    PubMed

    Higuchi, Akihiro; Inoue, Hiroyoshi; Kaneko, Yoshio; Oonishi, Erina; Tsubota, Kazuo

    2016-11-11

    The ocular surface is strongly affected by oxidative stress, which causes many ocular diseases including dry eye. Previously, we showed that selenium compounds, e.g., selenoprotein P and Se-lactoferrin, were candidates for treatment of dry eye. This paper shows the efficacy of Se-lactoferrin for the treatment of dry eye compared with Diquas as a control drug using two dry eye models and incorporation of lactoferrin into corneal epithelial cells via lactoferrin receptors. We show the efficacy of Se-lactoferrin eye drops in the tobacco smoke exposure rat dry eye model and short-term rabbit dry eye model, although Diquas eye drops were only effective in the short-term rabbit dry eye model. These results indicate that Se-lactoferrin was useful in the oxidative stress-causing dry eye model. Se-lactoferrin was taken into corneal epithelium cells via lactoferrin receptors. We identified LRP1 as the lactoferrin receptor in the corneal epithelium involved in lactoferrin uptake. Se-lactoferrin eye drops did not irritate the ocular surface of rabbits. Se-lactoferrin was an excellent candidate for treatment of dry eye, reducing oxidative stress by a novel mechanism.

  13. Selenium-binding lactoferrin is taken into corneal epithelial cells by a receptor and prevents corneal damage in dry eye model animals

    PubMed Central

    Higuchi, Akihiro; Inoue, Hiroyoshi; Kaneko, Yoshio; Oonishi, Erina; Tsubota, Kazuo

    2016-01-01

    The ocular surface is strongly affected by oxidative stress, which causes many ocular diseases including dry eye. Previously, we showed that selenium compounds, e.g., selenoprotein P and Se-lactoferrin, were candidates for treatment of dry eye. This paper shows the efficacy of Se-lactoferrin for the treatment of dry eye compared with Diquas as a control drug using two dry eye models and incorporation of lactoferrin into corneal epithelial cells via lactoferrin receptors. We show the efficacy of Se-lactoferrin eye drops in the tobacco smoke exposure rat dry eye model and short-term rabbit dry eye model, although Diquas eye drops were only effective in the short-term rabbit dry eye model. These results indicate that Se-lactoferrin was useful in the oxidative stress-causing dry eye model. Se-lactoferrin was taken into corneal epithelium cells via lactoferrin receptors. We identified LRP1 as the lactoferrin receptor in the corneal epithelium involved in lactoferrin uptake. Se-lactoferrin eye drops did not irritate the ocular surface of rabbits. Se-lactoferrin was an excellent candidate for treatment of dry eye, reducing oxidative stress by a novel mechanism. PMID:27833152

  14. Accelerated 20-year sunlight exposure simulation of a photochromic foldable intraocular lens in a rabbit model

    PubMed Central

    Werner, Liliana; Abdel-Aziz, Salwa; Peck, Carolee Cutler; Monson, Bryan; Espandar, Ladan; Zaugg, Brian; Stringham, Jack; Wilcox, Chris; Mamalis, Nick

    2011-01-01

    PURPOSE To assess the long-term biocompatibility and photochromic stability of a new photochromic hydrophobic acrylic intraocular lens (IOL) under extended ultraviolet (UV) light exposure. SETTING John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. DESIGN Experimental study. METHODS A Matrix Aurium photochromic IOL was implanted in right eyes and a Matrix Acrylic IOL without photochromic properties (n = 6) or a single-piece AcrySof Natural SN60AT (N = 5) IOL in left eyes of 11 New Zealand rabbits. The rabbits were exposed to a UV light source of 5 mW/cm2 for 3 hours during every 8-hour period, equivalent to 9 hours a day, and followed for up to 12 months. The photochromic changes were evaluated during slitlamp examination by shining a penlight UV source in the right eye. After the rabbits were humanely killed and the eyes enucleated, study and control IOLs were explanted and evaluated in vitro on UV exposure and studied histopathologically. RESULTS The photochromic IOL was as biocompatible as the control IOLs after 12 months under conditions simulating at least 20 years of UV exposure. In vitro evaluation confirmed the retained optical properties, with photochromic changes observed within 7 seconds of UV exposure. The rabbit eyes had clinical and histopathological changes expected in this model with a 12-month follow-up. CONCLUSIONS The new photochromic IOL turned yellow only on exposure to UV light. The photochromic changes were reversible, reproducible, and stable over time. The IOL was biocompatible with up to 12 months of accelerated UV exposure simulation. PMID:21241924

  15. Accelerated 20-year sunlight exposure simulation of a photochromic foldable intraocular lens in a rabbit model.

    PubMed

    Werner, Liliana; Abdel-Aziz, Salwa; Cutler Peck, Carolee; Monson, Bryan; Espandar, Ladan; Zaugg, Brian; Stringham, Jack; Wilcox, Chris; Mamalis, Nick

    2011-02-01

    To assess the long-term biocompatibility and photochromic stability of a new photochromic hydrophobic acrylic intraocular lens (IOL) under extended ultraviolet (UV) light exposure. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. A Matrix Aurium photochromic IOL was implanted in right eyes and a Matrix Acrylic IOL without photochromic properties (n = 6) or a single-piece AcrySof Natural SN60AT IOL (n = 5) in left eyes of 11 New Zealand rabbits. The rabbits were exposed to a UV light source of 5 mW/cm(2) for 3 hours during every 8-hour period, equivalent to 9 hours a day, and followed for up to 12 months. The photochromic changes were evaluated during slitlamp examination by shining a penlight UV source in the right eye. After the rabbits were humanely killed and the eyes enucleated, study and control IOLs were explanted and evaluated in vitro on UV exposure and studied histopathologically. The photochromic IOL was as biocompatible as the control IOLs after 12 months under conditions simulating at least 20 years of UV exposure. In vitro evaluation confirmed the retained optical properties, with photochromic changes observed within 7 seconds of UV exposure. The rabbit eyes had clinical and histopathological changes expected in this model with a 12-month follow-up. The new photochromic IOL turned yellow only on exposure to UV light. The photochromic changes were reversible, reproducible, and stable over time. The IOL was biocompatible with up to 12 months of accelerated UV exposure simulation. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  16. Hyperlipidemia-associated gene variations and expression patterns revealed by whole-genome and transcriptome sequencing of rabbit models

    PubMed Central

    Wang, Zhen; Zhang, Jifeng; Li, Hong; Li, Junyi; Niimi, Manabu; Ding, Guohui; Chen, Haifeng; Xu, Jie; Zhang, Hongjiu; Xu, Ze; Dai, Yulin; Gui, Tuantuan; Li, Shengdi; Liu, Zhi; Wu, Sujuan; Cao, Mushui; Zhou, Lu; Lu, Xingyu; Wang, Junxia; Yang, Jing; Fu, Yunhe; Yang, Dongshan; Song, Jun; Zhu, Tianqing; Li, Shen; Ning, Bo; Wang, Ziyun; Koike, Tomonari; Shiomi, Masashi; Liu, Enqi; Chen, Luonan; Fan, Jianglin; Chen, Y. Eugene; Li, Yixue

    2016-01-01

    The rabbit (Oryctolagus cuniculus) is an important experimental animal for studying human diseases, such as hypercholesterolemia and atherosclerosis. Despite this, genetic information and RNA expression profiling of laboratory rabbits are lacking. Here, we characterized the whole-genome variants of three breeds of the most popular experimental rabbits, New Zealand White (NZW), Japanese White (JW) and Watanabe heritable hyperlipidemic (WHHL) rabbits. Although the genetic diversity of WHHL rabbits was relatively low, they accumulated a large proportion of high-frequency deleterious mutations due to the small population size. Some of the deleterious mutations were associated with the pathophysiology of WHHL rabbits in addition to the LDLR deficiency. Furthermore, we conducted transcriptome sequencing of different organs of both WHHL and cholesterol-rich diet (Chol)-fed NZW rabbits. We found that gene expression profiles of the two rabbit models were essentially similar in the aorta, even though they exhibited different types of hypercholesterolemia. In contrast, Chol-fed rabbits, but not WHHL rabbits, exhibited pronounced inflammatory responses and abnormal lipid metabolism in the liver. These results provide valuable insights into identifying therapeutic targets of hypercholesterolemia and atherosclerosis with rabbit models. PMID:27245873

  17. Virulence and pathogenesis of the MSW and MSD strains of Californian myxoma virus in European rabbits with genetic resistance to myxomatosis compared to rabbits with no genetic resistance.

    PubMed

    Silvers, L; Inglis, B; Labudovic, A; Janssens, P A; van Leeuwen, B H; Kerr, P J

    2006-04-25

    The pathogenesis of two Californian strains of myxoma virus (MSW and MSD) was examined in European rabbits (Oryctolagus cuniculus) that were either susceptible to myxomatosis (laboratory rabbits) or had undergone natural selection for genetic resistance to myxomatosis (Australian wild rabbits). MSW was highly lethal for both types of rabbits with average survival times of 7.3 and 9.4 days, respectively, and 100% mortality. Classical clinical signs of myxomatosis were not present except in one rabbit that survived for 13 days following infection. Previously described clinical signs of trembling and shaking were observed in laboratory but not wild rabbits. Despite the high resistance of wild rabbits to myxomatosis caused by South American strains of myxoma virus, the MSW strain was of such high virulence that it was able to overcome resistance. The acute nature of the infection, relatively low viral titers in the tissues and destruction of lymphoid tissues, suggested that death was probably due to an acute and overwhelming immunopathological response to the virus. No virus was found in the brain. The MSD strain was attenuated compared to previously published descriptions and therefore was only characterized in laboratory rabbits. It is concluded that Californian MSW strain of myxoma virus is at the extreme end of a continuum of myxoma virus virulence but that the basic pathophysiology of the disease induced is not broadly different to other strains of myxoma virus.

  18. Detecting endotoxin contamination of ophthalmic viscosurgical devices: intracameral versus intravitreal assays in rabbits.

    PubMed

    Buchen, Shelley Y; Calogero, Don; Hilmantel, Gene; Eydelman, Malvina B

    2012-07-01

    To compare the sensitivities of intracameral and intravitreal assays in the rabbit model to determine the relative adequacy of these methods in detecting bacterial endotoxin contamination of ophthalmic viscosurgical devices (OVDs). Experimental, randomized animal study. Twenty New Zealand white rabbits. Rabbits were randomized into 4 groups to receive a cohesive or a dispersive OVD via intracameral or intravitreal injection. All 40 treated eyes (10 eyes of 5 animals in each group) received bilateral injection of OVD spiked with bacterial endotoxin at 7.0 endotoxin units/ml. All eyes were evaluated by slit-lamp biomicroscopy for inflammatory response at 3, 6, 9, 24, 48, and 72 hours after exposure. Eyes that received intravitreal injection were also dilated at 24, 48, and 72 hours and were re-examined by slit-lamp biomicroscopy and by indirect ophthalmoscopy. Conjunctival inflammation, anterior chamber (AC) flare, cells and fibrin, vitreous haze and cells, iridal hyperemia, corneal clouding, lens opacities, and onset times. Intracamerally injected eyes frequently showed conjunctival congestion, AC cells and flare, iridal hyperemia, and fibrin within 6 hours. Up to 80% showed AC cells and flare at 9 hours, and up to 70% showed fibrin at 24 hours. These signs diminished within 48 hours. Fibrin and cells also were seen on the lens surface of most of the eyes. Intravitreally injected eyes showed no signs of inflammation within 24 hours, other than some conjunctival inflammation. After the 24-hour time point, in addition to some conjunctival inflammation, some other signs of inflammation were observed infrequently in the intravitreally injected eyes, including minor vitreous cell reaction in 2 eyes. Although there was 1 dispersive OVD-treated eye with cells and fibrin on the lens capsule at 48 hours, no aqueous cells or flare were seen in the AC of any intravitreally injected eyes at any time during the course of the study. The rabbit intravitreal assay, when limited to

  19. Pharmacological evaluation of anti-inflammatory pyrrole-acetic acid derivative eye drops.

    PubMed

    Bucolo, C; Spadaro, A

    1997-08-01

    The effects of mucoadhesive eye drops containing a pyrrole-acetic acid derivative (tolmetin) at 0.5% concentration on ocular inflammation produced by sodium arachidonate in the rabbit's eye were evaluated. Furthermore, the bioavailability of the mucoadhesive formulation in the aqueous humor against an aqueous-based solution was compared. Tolmetin eye drops significantly reduced the signs of ocular inflammation elicited by sodium arachidonate on conjunctiva and iris. Tolmetin treatment significantly reduced the levels of prostaglandin E2, polymorphonuclear leukocytes and protein concentration in aqueous samples obtained from the eyes treated with arachidonate. The de novo production of prostaglandin E2 by corneas obtained from rabbits sacrificed 2 hours after arachidonate instillation were significantly higher in samples taken from controls than in corneas obtained from the eyes treated with tolmetin eye drops. Furthermore, the drug treatment significantly reduced the rise in intraocular pressure arachidonate-induced. The mucoadhesive formulation showed a higher bioavailability in aqueous humor compared to the aqueous-based solution both in the uninflamed and in the inflamed rabbit eyes.

  20. A case of low success of blind vaccination campaigns against myxomatosis and rabbit haemorrhagic disease on survival of adult European wild rabbits.

    PubMed

    Rouco, Carlos; Moreno, Sacramento; Santoro, Simone

    2016-10-01

    Vaccination campaigns against myxomatosis and rabbit haemorrhagic disease (RHD) are commonly used in translocation programs conducted for the purpose of recovering wild European rabbit populations in Iberian Mediterranean ecosystems. In most cases rabbits are vaccinated 'blind' (i.e. without assessing their prior immunological status) for economic and logistic reasons. However, there is conflicting evidence on the effectiveness of such an approach. We tested whether blind vaccination against myxomatosis and rabbit haemorrhagic disease improved rabbit survival in a rabbit translocation program where wild rabbits were kept in semi-natural conditions in three enclosures. We conducted nine capture sessions over two years (2008-2010) and used the information collected to compare the survival of vaccinated (n=511) versus unvaccinated (n=161) adult wild rabbits using capture-mark-recapture analysis. Average monthly survival was no different for vaccinated versus unvaccinated individuals, both in the period between release and first capture (short-term) and after the first capture onward (long-term). Rabbit survival was lower in the short term than in the long term regardless of whether rabbits were vaccinated or not. Lower survival in the short-term could be due to the stress induced by the translocation process itself (e.g. handling stress). However, we did not find any overall effect of vaccination on survival which could be explained by two non-exclusive reasons. First, interference of the vaccine with the natural antibodies in the donor population. Due to donor populations have high density of rabbits with, likely, high prevalence of antibodies as a result of previous natural exposure to these diseases. Second, the lack of severe outbreaks during the study period. Based on our findings we argue that blind vaccination of adult rabbits in translocation programs may be often mostly ineffective and unnecessarily costly. In particular, since outbreaks are hard to predict

  1. Divalent cations in tears, and their influence on tear film stability in humans and rabbits.

    PubMed

    Wei, Xiaojia Eric; Markoulli, Maria; Millar, Thomas J; Willcox, Mark D P; Zhao, Zhenjun

    2012-06-05

    Reduced tear film stability is reported to contribute to dry eye. Rabbits are known to have a more stable tear film than humans. Thus, we sought to examine the tears of rabbits and humans for metal cations, and to test how they influence tear film stability. Tears were collected from 10 healthy humans and 6 rabbits. Tear osmolality was measured by vapor pressure osmometer, and metals analyzed using inductively coupled plasma (ICP) mass spectrometry or ICP atomic emission spectroscopy. The influence of divalent cations on tears was analyzed by measuring surface tension using the Langmuir trough in vitro, using different concentrations of cations in the subphase, and grading the tear break-up in rabbits in vivo after instillation of chelating agents. Rabbit tears had a higher osmolality compared to humans. Major metals did not differ between species; however, rabbits had higher levels of Mg(2+) (1.13 vs. 0.39 mM) and Ca(2+) (0.75 vs. 0.36 mM). In rabbit tears in vitro, diminishing divalent cations resulted in a decrease in the maximum surface pressure from 37 to 30 mN/m. In vivo, an increase in the amount of tear film that was broken-up was found. In contrast, when changing divalent cation concentrations in human tears, the maximum surface pressure remained at 26 mN/m. The normal osmolality of rabbit tears is significantly higher than that in humans. While divalent cations had little influence on human tears, they appear to have an important role in maintaining tear film stability in rabbits.

  2. In vitro ocular metabolism and bioactivation of ketoconazole in rat, rabbit and human.

    PubMed

    Cirello, Amanda L; Dumouchel, Jennifer L; Gunduz, Mithat; Dunne, Christine E; Argikar, Upendra A

    2017-04-01

    Oral ketoconazole is clinically administered for treatment of severe cases for fungal keratitis. Pharmacodynamics and efficacy of oral and topical (ocular) ketoconazole have been explored in rabbit. However, metabolism of ketoconazole in the eye in any species is not well explored in any preclinical species or human. An understanding of ocular drug metabolism in the eye is crucial for ocular therapeutics to facilitate the risk assessment and development of potential drug candidates for the clinic. We aimed to investigate the metabolism of ketoconazole in rat, rabbit and human ocular S9 fractions. Metabolism in liver S9 fractions was also studied for a direct comparison. Eleven putative metabolites were identified in the in vitro incubations. Of these metabolites, six were present in rat ocular S9 whereas eight were present in rabbit and human ocular matrices. Metabolic pathways in rabbit and human ocular fractions suggested the formation of reactive intermediates in rabbit and human liver and ocular S9 incubations, which was confirmed with trapping studies. Herein, we report eight human ocular metabolites of ketoconazole for the first time. To the best of our knowledge, this is the first report of ocular metabolic pathways and ocular bioactivation of ketoconazole in preclinical species and human. Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  3. Corneal edema after overnight lid closure of rabbits wearing silicone rubber contact lenses.

    PubMed

    Koch, J M; Refojo, M F; Leong, F L

    1991-03-01

    Elastofilcon A silcone rubber contact lenses induce less corneal swelling than no lens wear during sleep, and increasing the central thickness and volume of the lens does not influence its overnight performance. We sought to elucidate whether a silicone rubber lens can promote the distribution of atmospheric O2 on the cornea through a small interpalpebral opening under closed-eye conditions. Three groups of rabbit eyes comprised 12 eyes wearing Silflex (Dk 79.8 barrer) lenses, 12 with elastofilcon A (Dk 340 barrer) lenses, and 12 without lenses. All eyes were surgically closed overnight; six eyes in each group had a complete lid closure and six eyes had a partial tarsorrhaphy that left a small, central gap approximately 3 mm in length. When the lids were opened the next morning, the partially closed elastofilcon A eyes showed less corneal swelling (6.2 +/- 1.4%) than the partially closed no-lens eyes did (9.6 +/- 1.3%) (p less than 0.01), whereas the partially closed Silflex eyes were significantly more swollen (12.8 +/- 2.1%) (p = 0.01) than the other two partially closed groups were. The completely closed eyes showed no significant difference in corneal swelling among the groups. These results indicate that small lid gaps during sleep may lead to less corneal swelling when elastofilcon A lenses are used than with no lenses.

  4. [Experimental syringomyelia in rabbits and rats after localized spinal arachnoiditis].

    PubMed

    Tatara, N

    1992-12-01

    In order to produce syringomyelia, localized arachnoiditis was created in adult New Zealand albino rabbits and Wistar rats by the injection of kaolin into the thoracic spinal subarachnoid space and incision of the dura mater of the thoracic spinal cord. The rabbits and rats were divided into 3 groups; the control group, dural incision group (DG) and kaolin injection group (KG). Each rabbit was sacrificed at 4, 8, 12 and 16 weeks after the operation. Each rat was sacrificed at 8 and 16 weeks after the operation. Cavity formation in the cord of all rabbits was examined by ultrasound. All animals were perfused with 10% neutral beffered formalin at 150 cm H2O pressure, and histological examination was performed with Luxol fast blue (LFB) and hematoxylin and eosin (H&E) stains. Results obtained: (1) Cavity formation was noted in 6 of 16 DG of rabbit (37.5%), 5 of 16 KG of rabbit (31.2%) and 2 of 9 KG of rat (22.2%) with histological verification. With use of ultrasound, cavity was noted in 3 of 16 DG rabbits (12.5%) and 2 of 16 KG rabbits (18.8%). (2) Cavity formation was present in the cord adjacent to the marked adhesive arachnoiditis both in rabbits and in rats. (3) Cavity was noted in the ischemic area. (4) In 2 rabbits in which kaolin encircled whole surface of the spinal cord, hydromyelia was formed communicating with enlarged central canal caudad from the kaolin subarachnoid block. (5) Histological examination showed obliteration or narrowing of lumen of the small pial vessels involved in the adhesive arachnoiditis. In the cord parenchyma adjacent to the arachnoiditis, multiple spots of demyelination due secondary to ischemia demonstrated by LFB stain were noted. On the other hand, in the cord with the pia-arachnoid remained uninvolved, no demyelination was observed. (6) Localized adhesive arachnoiditis consisted of proliferation of fibrous tissue, lymphocytic infiltration and obliterating processes of small pial vessels involved in it. These data suggest that

  5. Urethral healing in rabbits.

    PubMed

    Scherz, H C; Kaplan, G W; Boychuk, D I; Landa, H M; Haghighi, P

    1992-08-01

    We studied urethral healing in New Zealand white rabbits by histological examination after insult (urethral catheter) or injury (urethrotomy) specifically for acute and chronic inflammation, fibrosis, fistulas, squamous metaplasia, foreign body giant cells and urethral dilatation. Urethral catheterization resulted in increased inflammation and fibrosis compared to noncatheterized animals. Skin closure techniques and materials resulted in an inflammatory response that may extend to and involve the urethra. Minor differences in suture size were not an important variable but the persistence of suture material may have a role in the degree of inflammation and the formation of foreign body giant cells. Transepithelial closure techniques drag epithelial cells into subcutaneous tissues and may predispose to fistula formation.

  6. Unilateral persistent hyperplastic tunica vasculosa lentis and persistent hyperplastic primary vitreous in a rabbit.

    PubMed

    Boillot, Thomas; Graille, Mélanie; Williams, David; Rosolen, Serge G

    2015-11-01

    A 3-month wild rabbit was presented for examination of ocular opacities in the left eye. A complete bilateral ocular examination including slit-lamp examination, indirect ophthalmoscopy, tonometry, and ultrasound biomicroscopy was performed. Biomicroscopy of the lens of the left eye showed a retrolental fibrovascular membrane causing leukocoria. The opacity prevented biomicroscopy of the vitreous and funduscopy OS. No other disorder was present in either eye. Ultrasound examination did not show any difference between the right and left eye. Histopathological examination showed a 50-μm thick, preretinal, retrolental, nonpigmented, fibrovascular tissue. Posterior synechiae were present, but no other lesion of the posterior segment was found in this eye. These ocular abnormalities are consistent with a persistent hyperplastic tunica vasculosa lentis and persistent hyperplastic primary vitreous (PHTVL/PHPV), similar to those described in other species.

  7. Fatal case of hemolytic-uremic syndrome in an adult due to a rare serogroup O91 Entero hemorrhagic Escherichia coli associated with a Clostridium difficile infection. More than meets the eye.

    PubMed

    Guillard, Thomas; Limelette, Anne; Le Magrex-Debar, Elisabeth; Wynckel, Alain; Gouali, Malika; Mariani-Kurkdjian, Patricia; Guyot-Colosio, Charlotte; de Champs, Christophe

    2015-08-01

    Hemolytic-uremic syndrome due to enterohemorrhagic Escherichia coli, belonging to serogroup O91 has rarely been described. We report here a case of post-diarrheal HUS due to EHEC O91 in an elderly patient for whom diagnosis was delayed given a previously diagnosed C. difficile infection. This case highlights the usefulness of Shiga-toxin detection.

  8. Freezability genetics in rabbit semen.

    PubMed

    Lavara, R; Mocé, E; Baselga, M; Vicente, J S

    2017-10-15

    The aim of this study was to estimate the heritability of semen freezability and to estimate the genetic correlation between frozen-thawed sperm traits and the growth rate in a paternal rabbit line. Estimated heritabilities showed that frozen-thawed semen traits are heritable (ranged between 0.08 and 0.15). In the case of Live-FT (percentage of viable sperm after freezing), the estimated heritability is the highest one, and suggests the possibility of effective selection. After the study of genetic correlations it seems that daily weight gain (DG) was negatively correlated with sperm freezability, but no further conclusions could be drawn due to the high HPD95%. More data should be included in order to obtain better accuracy for the estimates of these genetic correlations. If the results obtained at present study were confirmed, it would imply that selection for DG could alter sperm cell membranes or seminal plasma composition, both components related to sperm cryoresistance. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. [The control of humoral transport of the eye tissues].

    PubMed

    Rapis, E G; Tumanov, V P; Levin, Iu M; Kurbanov, N Kh

    1991-02-01

    Three series of investigations were carried out in experiments on rabbits with administration under the conjunctiva or by means of electrophoresis of lymphotrophic preparations of different mechanisms of actions with the use of a morphological marker: Gerot's mass and Indian ink jelly with subsequent histological study of the eyeball. Dalargin dilated structured liquorolymphatic drainage ducts of the eye. Terrylythin produced a selective effect on the pigment epithelium of the retina, and mannitol provided penetration of the marker into the retina neurons. Thus, it has been shown that it is possible to control selectively the humoral transport of some tissues of the eye by means of lymphotrophic agents.

  10. Functional eye movement disorders.

    PubMed

    Kaski, D; Bronstein, A M

    2017-01-01

    Functional (psychogenic) eye movement disorders are perhaps less established in the medical literature than other types of functional movement disorders. Patients may present with ocular symptoms (e.g., blurred vision or oscillopsia) or functional eye movements may be identified during the formal examination of the eyes in patients with other functional disorders. Convergence spasm is the most common functional eye movement disorder, but functional gaze limitation, functional eye oscillations (also termed "voluntary nystagmus"), and functional convergence paralysis may be underreported. This chapter reviews the different types of functional eye movement abnormalities and provides a practical framework for their diagnosis and management.

  11. Medical Management of Combat Laser Eye Injuries

    DTIC Science & Technology

    1988-10-01

    damage may significantly degrade vision due to increased light scatter from opacities or due to gross rupture. In addition, iritis (intraocular...intraocular inflammation ( iritis ). The anterior chamber should be examined for blood. Snellen Acuity A "standard" eye chart (for distance or near) is used to...Patch onlY the eye with the injured cornea. Any associated iritis and its attendant pain can be treated with pupillary dilation using cyclogel 1%, one

  12. The cottontail rabbits of Virginia

    USGS Publications Warehouse

    Llewellyn, L.M.; Handley, C.O.

    1945-01-01

    Five races of cottontail rabbits belonging to three species occur in Virginia. One of them, the Mearns cottontail (Sylvilagus floridanus mearnsi), is reported here for the first time. It occurs in six southwestern counties of the state, while the eastern cottontail (S. f. mallurus) occurs in the remainder of the state with the exception of Smith and Fishermans islands off the eastern coast of Cape Charles, where it is replaced by Hitchens cottontail (S. f. hitchensi). The New England cottontail (S. transitionalis) is found on the higher mountain peaks, above 3000 feet, and the swamp rabbit (S. palustris) occurs in the Dismal Swamp region of southeastern Virginia.....The height of the breeding season for the eastern cottontail in Virginia is March and April, but breeding continues through the entire year except in December and January. The average litter size based on embryo counts was 4.7. The sex ratio of 234 specimens from all parts of the state, taken mostly in the December to February period, was 53 males to 47 females. That of a group of 145 rabbits live-trapped at Blacksburg during February and Marchwas 58 males to 42 females. The figures show that males are more active than females during the winter months, and therefore are more easily taken then....In transplanting cottontails from one section of the state to another, it is recommended that only cottontails of the same race as those originally present in the region being restocked be released there....Tularemia is not a common disease among rabbits in Virginia, but the rabbit ticks are often carriers of the disease and may transmit it to rabbits. Rabbit ticks are also found to be carriers of Rocky Mountain fever and American Q. fever. After the ticks drop off the rabbits to hibernate in the ground, which is likely to occur during mid-winter in Virginia, there is relatively little danger of humans contracting tularemia by contact with rabbits. Present laws in Virginia which prohibit rabbit hunting until the

  13. "Rabbit Proof Fence": A Struggle for Cultural Existence

    ERIC Educational Resources Information Center

    Al-Momani, Hassan Ali Abdullah

    2016-01-01

    The main goal of this paper is to depict the struggle for cultural existence in "Rabbit Proof Fence." It also reflects the cultural conflict represented in the three aboriginal girls' characters which is due to their rejection and resistance for the colonialists' culture. Besides, the paper presents the cognitive analysis of the cultural…

  14. The Eyes Are the Windows to the Mind: Direct Eye Gaze Triggers the Ascription of Others' Minds.

    PubMed

    Khalid, Saara; Deska, Jason C; Hugenberg, Kurt

    2016-12-01

    Eye gaze is a potent source of social information with direct eye gaze signaling the desire to approach and averted eye gaze signaling avoidance. In the current work, we proposed that eye gaze signals whether or not to impute minds into others. Across four studies, we manipulated targets' eye gaze (i.e., direct vs. averted eye gaze) and measured explicit mind ascriptions (Study 1a, Study 1b, and Study 2) and beliefs about the likelihood of targets having mind (Study 3). In all four studies, we find novel evidence that the ascription of sophisticated humanlike minds to others is signaled by the display of direct eye gaze relative to averted eye gaze. Moreover, we provide evidence suggesting that this differential mentalization is due, at least in part, to beliefs that direct gaze targets are more likely to instigate social interaction. In short, eye contact triggers mind perception.

  15. Optical properties of the mouse eye

    PubMed Central

    Geng, Ying; Schery, Lee Anne; Sharma, Robin; Dubra, Alfredo; Ahmad, Kamran; Libby, Richard T.; Williams, David R.

    2011-01-01

    The Shack-Hartmann wavefront sensor (SHWS) spots upon which ocular aberration measurements depend have poor quality in mice due to light reflected from multiple retinal layers. We have designed and implemented a SHWS that can favor light from a specific retinal layer and measured monochromatic aberrations in 20 eyes from 10 anesthetized C57BL/6J mice. Using this instrument, we show that mice are myopic, not hyperopic as is frequently reported. We have also measured longitudinal chromatic aberration (LCA) of the mouse eye and found that it follows predictions of the water-filled schematic mouse eye. Results indicate that the optical quality of the mouse eye assessed by measurement of its aberrations is remarkably good, better for retinal imaging than the human eye. The dilated mouse eye has a much larger numerical aperture (NA) than that of the dilated human eye (0.5 NA vs. 0.2 NA), but it has a similar amount of root mean square (RMS) higher order aberrations compared to the dilated human eye. These measurements predict that adaptive optics based on this method of wavefront sensing will provide improvements in retinal image quality and potentially two times higher lateral resolution than that in the human eye. PMID:21483598

  16. Towards a new in vitro model of dry eye: the Ex Vivo Eye Irritation Test.

    PubMed

    Spöler, Felix; Frentz, Markus; Schrage, Norbert F

    2010-01-01

    Understanding of dry eye syndrome (DES) today is driven by in vivo analysis of tear osmolarity, tear film break up time, impression cytology and description of symptoms. Existing in vivo models of DES need severe alterations of tear production or corneal integrity. For a more detailed analysis of DES under particular environmental and treatment conditions a considerable lack of in vitro methods exists. The main disadvantage of current in vitro models is the limited experimental time frame of only several hours and the impossibility to evaluate healing of epithelial defects. In the present study, evidence is given that these restrictions can be overcome by modifying the established Ex Vivo Eye Irritation Test (EVEIT) to realize a model system for DES. This test is based on abattoir rabbit eyes allowing an experimental time frame of up to 21 days using self-healing corneal cultures. In first experiments it is demonstrated that different severity levels of dry eye can be simulated in the EVEIT system. High-resolution optical coherence tomography (OCT) is applied to monitor the initial phase of DES under evaporative stress acting on the cornea. We observed changes in corneal layer thicknesses and in scattering properties of the stroma, which are sensitive indicators of environmental stress leading to irritation of the ocular surface under dry eye conditions. The combination of corneal culture under desiccating conditions and OCT monitoring offers a new perspective in understanding and treating of DES and is expected to allow for significant pharmacological screening tests. Copyright 2010 S. Karger AG, Basel.

  17. Primary and secondary experimental infestation of rabbits (Oryctolagus cuniculus) with Sarcoptes scabiei from a wild rabbit: factors determining resistance to reinfestation.

    PubMed

    Casais, Rosa; Dalton, Kevin P; Millán, Javier; Balseiro, Ana; Oleaga, Alvaro; Solano, Paloma; Goyache, Félix; Prieto, José Miguel; Parra, Francisco

    2014-06-16

    Studies of sarcoptic mange and immunity are hampered by lack of mite sources and natural infestation models. We have investigated the clinical and pathological signs, specific IgG response and acquired immunity in naïve New Zealand White rabbits (Oryctolagus cuniculus) experimentally infested with Sarcoptes scabiei originally isolated from a clinically affected free-living European wild rabbit. Twenty rabbits were infested using two methods, direct contact for a 24 h period with a seeder rabbit simulating the natural process of infestation and application of a dressing holding approximately 1800 live mites on each hind limb (foot area) for a 24h period. Eight weeks post infestation, rabbits were treated with ivermectin and infestation cleared. Eight weeks later seventeen previously infested and four uninfested naïve controls were then re-exposed to the same S. scabiei variety using the same methods and followed for another 8 weeks. The progress of the disease was markedly more virulent in the animals infested by contact, indicating that the effective dose of mites managing to thrive and infest each rabbit by this method was higher. Nevertheless, infestation by contact resulted in partial protection to reexposure, rabbits developed high non-protective antibody titres upon reinfestation and presented severe clinical signs. However, rabbits reinfested by dressing developed lower IgG titres, and presented high levels of resistance to reinfestation, which might be due to induction of a strong local cellular response in the inoculation point that killed the mites and resulted in a lower mite effective dose, with subsequent reduced lesion development. Statistical analysis showed that sex, method of infestation and previous exposure are key factors determining the ability of rabbits to develop immunity to this disease. The rabbit-mange model developed will allow the further study of immunity and resistance to this neglected pathogen using a natural host system.

  18. Eye closure enhances dark night perceptions

    PubMed Central

    Brodoehl, Stefan; Klingner, Carsten M.; Witte, Otto W.

    2015-01-01

    We often close our eyes when we explore objects with our fingers to reduce the dominance of the visual system over our other senses. Here we show that eye closure, even in complete darkness, results in improved somatosensory perception due to a switch from visual predominance towards a somatosensory processing mode. Using a tactile discrimination task and functional neuroimaging (fMRI) data were acquired from healthy subjects with their eyes opened and closed in two environments: under ambient light and in complete darkness. Under both conditions the perception threshold decreased when subjects closed their eyes, and their fingers became more sensitive. In complete darkness, eye closure significantly increased occipital blood-oxygen-level-dependent (BOLD) activity in the somatosensory and secondary visual processing areas. This change in brain activity was associated with enhanced coupling between the sensory thalamus and somatosensory cortex; connectivity between the visual and somatosensory areas decreased. The present study demonstrates that eye closure improves somatosensory perception not merely due to the lack of visual signals; instead, the act of closing the eyes itself alters the processing mode in the brain: with eye closure the brain switches from thalamo-cortical networks with visual dominance to a non-visually dominated processing mode. PMID:26012706

  19. Penetrating eye injuries in road traffic accidents.

    PubMed

    Patel, B C; Morgan, L H

    1988-03-01

    A review of all penetrating eye injuries treated by the Manchester Eye Hospital over four years (1 February 1982-31 January 1986) was undertaken. One hundred and ninety-six penetrating eye injuries were seen, of which 16 (8.2%) were due to road traffic accidents. Eight patients (nine eyes) were seen in the 12 months prior to the introduction of the seat-belt legislation on 1 February 1983. None of these patients was wearing a seat-belt whereas two of the eight patients (10 eyes) seen after the seat-belt legislation were. Both these patients suffered severe visual loss due to intraocular glass from shattered windscreens. Three patients had bilateral penetrating eye injuries, one before and two after the seat-belt legislation. Two of the nine eyes involved prior to the legislation and three of the 10 eyes after the legislation had an eventual visual acuity of 6/12 or better. In the majority of patients, failure to wear seat-belts or defective use is to blame. Flying glass from shattered toughened windscreens is a preventable danger. Nine of the 16 patients were first seen in the general accident and emergency department and, of these, seven did not have visual acuities recorded prior to referral to an ophthalmologist. The importance of measurement of the visual acuity and detection of an afferent pupillary defect is stressed based on these findings.

  20. Eye closure enhances dark night perceptions.

    PubMed

    Brodoehl, Stefan; Klingner, Carsten M; Witte, Otto W

    2015-05-27

    We often close our eyes when we explore objects with our fingers to reduce the dominance of the visual system over our other senses. Here we show that eye closure, even in complete darkness, results in improved somatosensory perception due to a switch from visual predominance towards a somatosensory processing mode. Using a tactile discrimination task and functional neuroimaging (fMRI) data were acquired from healthy subjects with their eyes opened and closed in two environments: under ambient light and in complete darkness. Under both conditions the perception threshold decreased when subjects closed their eyes, and their fingers became more sensitive. In complete darkness, eye closure significantly increased occipital blood-oxygen-level-dependent (BOLD) activity in the somatosensory and secondary visual processing areas. This change in brain activity was associated with enhanced coupling between the sensory thalamus and somatosensory cortex; connectivity between the visual and somatosensory areas decreased. The present study demonstrates that eye closure improves somatosensory perception not merely due to the lack of visual signals; instead, the act of closing the eyes itself alters the processing mode in the brain: with eye closure the brain switches from thalamo-cortical networks with visual dominance to a non-visually dominated processing mode.

  1. Eye muscle test (image)

    MedlinePlus

    ... the extraocular muscles which results in uncontrolled eye movements. The test involves moving the eyes in six different directions in space to evaluate the proper functioning of the extraocular ...

  2. Eye Drop Tips

    MedlinePlus

    ... Involved News About Us Donate In This Section Eye Drop Tips en Español email Send this article ... the reach of children. Steps For Putting In Eye Drops: Start by tilting your head backward while ...

  3. Diabetic Eye Problems

    MedlinePlus

    ... too high. Over time, this can damage your eyes. The most common problem is diabetic retinopathy. It ... light-sensitive tissue at the back of your eye. You need a healthy retina to see clearly. ...

  4. Eye Injuries (For Parents)

    MedlinePlus

    ... and comfortable as possible until help arrives. continue Chemical Exposure Many chemicals, even those found around the house, can damage an eye. If your child gets a chemical in the eye and you know what it ...

  5. Recommended Sports Eye Protectors

    MedlinePlus

    ... Eye Emergencies How to Jump Start a Car Battery Safely Electronic Screens and Your Eyes Nutrition and ... External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy ...

  6. Diabetes and eye disease

    MedlinePlus

    ... have damage to the blood vessels in your eye, some types of exercise can make the problem worse. Check with your health care provider before starting an exercise program. Other eye problems that can occur in people with diabetes ...

  7. Visual recovery from optic atrophy following acute optic neuropathy in the fellow eye.

    PubMed

    Ornek, Kemal; Ornek, Nurgül

    2012-06-01

    The left eye of a 65-year-old male was blind due to optic atrophy and only seeing eye had also dry type age-related macular degeneration. An anterior ischemic optic neuropathy developed in the better seeing eye. Vision recovered in the blind eye in a short time after losing the better eye. Gaining some vision in a blind eye may be an adaptation of visual pathway in such patients.

  8. Pulmonary vascular disease in a rabbit a high altitude

    NASA Astrophysics Data System (ADS)

    Heath, Donald; Williams, David; Rios-Datenz, Jaime; Gosney, John

    1990-03-01

    A male weanling rabbit of the New Zealand White strain, born and living at an altitude of 3800 m in La Paz, Bolivia, developed right ventricular hypertrophy. This was found to be associated with growth of vascular smooth muscle cells in the intima of pulmonary arterioles, and contrasted with muscularization of the walls of pulmonary arterioles, without extension into the intima, found in a healthy, high-altitude control rabbit of the same strain. A low-altitude control showed no such muscularization. It is concluded that alveolar hypoxia, acting directly or through an intermediate agent, is a growth factor for vascular smooth muscle cells in pulmonary arterioles. This is the first report of pulmonary vascular disease due to high altitude in rabbits.

  9. Rabbit anti-rabies immunoglobulins production and evaluation.

    PubMed

    Liu, Xinjian; Liu, Qiongqiong; Feng, Xiaomin; Tang, Qi; Wang, Zhongcan; Li, Suqing; Feng, Zhenqing; Zhu, Jin; Guan, Xiaohong

    2011-04-01

    Due to the disadvantages of human and equine rabies immunoglobulin, it is necessary to develop a substitute for HRIG and ERIG, especially for those people living in the developing countries. Because of higher affinity and lower immunogenicity of rabbit's immunoglobulins, anti-rabies immunoglobulins specific to rabies virus were produced in rabbits as a bioreactor, and had been characterized by ELISA, affinity assay, immunofluorescence assay (IFA), immunocytochemistry, rapid fluorescent focus inhibition test (RFFIT). ELISA, affinity assay and IFA showed that rabbit RIG (RRIG) bound specifically to rabies virions. RFFIT result showed that RRIG has neutralization activity. This result was confirmed in vivo in a Kunming mouse challenge model and the protection rate of the treatment with RRIG was higher (25%) than that offered by HRIG when mice were challenged with a lethal RV dose. Our results demonstrate that RRIG is safe and efficacious as a candidate drug to replace rabies immunoglobulin in post-exposure prophylaxis.

  10. Distribution of diuretics and hypoglycemic sulfonylureas in rabbit erythrocytes.

    PubMed

    Yoshitomi, H; Kiko, S; Ikeda, K; Goto, S

    1983-03-01

    The distribution of three sulfonylureas and six diuretics in rabbit erythrocytes was studied in vitro at 37 degrees C. The drugs were taken up by the erythrocyte compartment, and distribution equilibrium was reached within 60 min of incubation. A distribution percentage in erythrocyte compartment was maintained at roughly constant value over the whole concentration range of drugs. Therefore, a linear relationship was established between total concentrations of drug in whole blood or erythrocyte suspension and in the erythrocyte compartment. Bovine serum albumin combined with the erythrocyte suspension appeared to reduce drug distribution in the erythrocyte compartment. Whole blood obtained from renal failure rabbits showed greater distribution of drug in the erythrocyte compartment compared with the whole blood of a normal rabbit. This might be due to a change in plasma protein binding ability related to the progress of renal failure.

  11. [Control of lymph-drainage tracts of the eye by the use of dalargin].

    PubMed

    Rapis, E G; Tumanov, V P; Levin, Iu M; Kurbanov, N Kh

    1990-10-01

    The objective was to study dalargin in experiment and its effect on drainage tracts in norm and with experimental hypertension, modulating secondary glaucoma. Investigations have been made on 82 rabbit eyes. The overall results show, that subconjunctival and electrophoretic dalargin injection of (0.1%-0.2-0.5 ml) causes the expansion of anterior and posterior lymph-drainage tracts of the eye and have hypotensive effect for ocular hypertension and secondary glaucoma.

  12. [Pathological changes of the cornea in rabbits with hyphema and concurrent ocular hypertension].

    PubMed

    Wang, Feng-yun; Lu, Xiao-he; Zhang, Cai-xia; Bai, Lang; Zhang, Jing; Zhong, Yan-yan; Wang, Shuang-shuang

    2010-03-01

    To evaluate the impact of hyphema secondary to high intraocular pressure on corneal pathology in rabbits. Thirty adult New Zealand rabbit were randomized into 3 equal groups, and in each rabbit, one eye served as the experimental eye with the other as the control eye. In the experimental eye, autoblood was injected into the anterior chamber to induce high intraocular pressure maintained for 3, 5, or 8 days. Only saline was injected into the control eye. After the injections, the cornea was observed with slit-lamp microscopy, and at 3, 5, or 8 days, the experimental and control eyes were taken from the 3 groups for microscopic examination of the corneas to detect the occurrence of cornea bloodstain with prolonged high intraocular pressure. Corneal edema, elastic fibers changes, growth of new blood vessels, changes of eosinophils, fibroblasts, lymphocytes and plasma cells, as well as the pathological changes of the corneal layers were observed and compared between the experimental and control eyes. Maintenance of high intraocular pressure for 8 days resulted in the most severe corneal edema and thickening, and histopathologically, the corneal stroma showed widened space between the elastic fibers and obvious fiber distortion. Neovascularization was seen in the marginal cornea where eosinophil infiltration occurred with a small number of lymphocytes, plasma cells and fiber cells. All the three groups showed more obvious edema in the posterior than in the anterior cornea. Prolonged hyphema with ocular hypertension results in aggravation of corneal edema, and corneal blood staining does not occur until 8 days of high intraocular pressure but corneal elastic fiber disruption can be seen, suggesting the impending irreversible pathological changes of cornea.

  13. Determination of a No-Observable Effect Level for Endotoxin Following a Single Intravitreal Administration to Dutch Belted Rabbits.

    PubMed

    Bantseev, Vladimir; Miller, Paul E; Bentley, Ellison; Schuetz, Chris; Streit, Tim M; Christian, Brian J; Farman, Cindy; Booler, Helen; Thackaberry, Evan A

    2017-03-01

    The purpose of this study was to characterize the inflammatory response and determine a no-observable effect level (NOEL) in rabbit eyes after endotoxin intravitreal (ITV) injection. Fifty-three naïve male Dutch Belted rabbits were treated with a single 50-μL ITV injection ranging from 0.01 to 0.75 endotoxin units/eye (EU/eye) and monitored for up to 42 days post treatment. Ophthalmic examination included slit-lamp biomicroscopy and indirect ophthalmoscopy. Laser flare photometry was performed in a subset of animals. On days 2, 8, 16, and 43, a subset of animals was necropsied and eyes processed for histopathological evaluation. Intravitreal injection of endotoxin at ≥0.05 EU/eye resulted in a dose-related anterior segment inflammation response. No aqueous flare or cell response was noted in the 0.01 EU/eye dose group. A more delayed posterior segment response characterized by vitreal cell response was observed beginning on day 5, peaking on day 9, and decreasing starting on day 16 that persisted at trace to a level of 1+ on day 43. Microscopy findings of infiltrates of minimal mixed inflammatory cells in the vitreous and subconjunctiva and proteinaceous fluid in the anterior chamber and/or vitreous were observed in eyes given ≥0.1 EU/eye. We defined the NOEL for ITV endotoxin to be 0.01 EU/eye, suggesting that the vitreal cavity is more sensitive to the effects of endotoxin than the anterior segment and aqueous chamber. These data highlight the importance of assessing endotoxin level in intravitreal formulations, as levels as low as 0.05 EU/eye may confound the safety evaluations of intravitreal therapeutics in rabbits.

  14. Infrared Eye: Prototype 2

    DTIC Science & Technology

    2016-06-07

    The Infrared (IR) Eye was developed with support from the National Search and Rescue Secretariat (NSS), in view of improving the efficiency of...airborne search-and rescue operations. The IR Eye concept is based on the human eye and uses simultaneously two fields of view to optimize area coverage and...within the wide field and slaved to the operator’s line of sight by means of an eye -tracking system. The images from both cameras are fused and shown

  15. Is the new variant RHDV replacing genogroup 1 in Portuguese wild rabbit populations?

    PubMed

    Lopes, Ana M; Correia, Jorge; Abrantes, Joana; Melo, Pedro; Ramada, Margarida; Magalhães, Maria J; Alves, Paulo C; Esteves, Pedro J

    2014-12-30

    The Lagovirus rabbit hemorrhagic disease virus (RHDV), a member of the family Caliciviridae, severely affects European rabbit (Oryctolagus cuniculus) populations by causing rabbit hemorrhagic disease (RHD). RHDV is subdivided in six genogroups but, more recently, a new RHDV variant with a unique genetic and antigenic profile emerged. We performed a study in rabbits found dead in the field during 2013 and 2014 in Portugal to determine the prevalence of this new variant versus the classical RHDV. Fifty-seven liver samples were screened for the presence of RHDV and positive samples were genotyped. All cases of RHDV infection were caused by the new variant. The only former genogroup circulating in Portugal, G1, was not detected. We hence conclude that the new RHDV variant is replacing G1 in Portugal, probably due to a selective advantage. This sudden and rapid replacement emphasizes the necessity of continued monitoring of wild rabbit populations.

  16. Vitreous pharmacokinetics and electroretinographic findings after intravitreal injection of acyclovir in rabbits

    PubMed Central

    Damico, Francisco Max; Scolari, Mariana Ramos; Ioshimoto, Gabriela Lourençon; Takahashi, Beatriz Sayuri; da Silva Cunha, Armando; Fialho, Sílvia Ligório; Bonci, Daniela Maria; Gasparin, Fabio; Ventura, Dora Fix

    2012-01-01

    OBJECTIVES: Acute retinal necrosis is a rapidly progressive and devastating viral retinitis caused by the herpesvirus family. Systemic acyclovir is the treatment of choice; however, the progression of retinal lesions ceases approximately 2 days after treatment initiation. An intravitreal injection of acyclovir may be used an adjuvant therapy during the first 2 days of treatment when systemically administered acyclovir has not reached therapeutic levels in the retina. The aims of this study were to determine the pharmacokinetic profile of acyclovir in the rabbit vitreous after intravitreal injection and the functional effects of acyclovir in the rabbit retina. METHODS: Acyclovir (Acyclovir; Bedford Laboratories, Bedford, OH, USA) 1 mg in 0.1 mL was injected into the right eye vitreous of 32 New Zealand white rabbits, and 0.1 mL sterile saline solution was injected into the left eye as a control. The animals were sacrificed after 2, 9, 14, or 28 days. The eyes were enucleated, and the vitreous was removed. The half-life of acyclovir was determined using high-performance liquid chromatography. Electroretinograms were recorded on days 2, 9, 14, and 28 in the eight animals that were sacrificed 28 days after injection according to a modified protocol of the International Society for Clinical Electrophysiology of Vision. RESULTS: Acyclovir rapidly decayed in the vitreous within the first two days after treatment and remained at low levels from day 9 onward. The eyes that were injected with acyclovir did not present any electroretinographic changes compared with the control eyes. CONCLUSIONS: The vitreous half-life of acyclovir is short, and the electrophysiological findings suggest that the intravitreal delivery of 1 mg acyclovir is safe and well tolerated by the rabbit retina. PMID:22948462

  17. Eye drop neurology.

    PubMed

    Bennetto, Luke; Guly, Catherine; Ormerod, Ian; Plant, Gordon T

    2014-06-01

    Eye drops can help to diagnose and prevent complications of neurological disorders. Guttae ophthalmicae (eye drops) are generally safe because the drugs rarely achieve significant systemic concentrations, although there are rare exceptions. This article covers contemporary pharmacological pupil testing; how to dilate a pupil safely; common reasons why pupils do not respond to drops; and corneal lubrication to prevent complications of weak eye closure.

  18. Eye Movements and Learning.

    ERIC Educational Resources Information Center

    Nesbit, Larry L.

    Research on the use of eye movement indices (such as number of fixations, the average fixation duration, and saccadic movements) as a measure of cognitive processing is reviewed in this paper. Information is provided on the physiology of the eye, computer applications to eye movement study, the influence of stimulus materials and intelligence on…

  19. Fish eye optics

    NASA Astrophysics Data System (ADS)

    Hudec, R.; Michalova, S.

    2017-07-01

    We report on small student (high—school) project of the Czech Academy of Sciences dealing with animal (fish) eyes and possible application in science and technology. Albeit most fishes have refractive eyes, the recent discoveries confirm that some fishes have reflective eyes with strange arrangements as well.

  20. Dwarf Eye Disorder

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Johns Hopkins researchers at the Wilmer Eye Institute have discovered what appears to be the first human gene mutation that causes extreme farsightedness. The researchers report that nanophthalmos, Greek for "dwarf eye," is a rare, potentially blinding disorder caused by an alteration in a gene called MFRP that helps control eye growth and…

  1. Dwarf Eye Disorder

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Johns Hopkins researchers at the Wilmer Eye Institute have discovered what appears to be the first human gene mutation that causes extreme farsightedness. The researchers report that nanophthalmos, Greek for "dwarf eye," is a rare, potentially blinding disorder caused by an alteration in a gene called MFRP that helps control eye growth and…

  2. Eye Movements and Learning.

    ERIC Educational Resources Information Center

    Nesbit, Larry L.

    Research on the use of eye movement indices (such as number of fixations, the average fixation duration, and saccadic movements) as a measure of cognitive processing is reviewed in this paper. Information is provided on the physiology of the eye, computer applications to eye movement study, the influence of stimulus materials and intelligence on…

  3. Hepatoprotective and toxicological studies of Salvia bucharica methanolic extract in rabbits.

    PubMed

    Ahmad, Mansoor; Muhammed, Shafi; Mehjabeen, -; Jahan, Noor

    2014-11-01

    Most of the species of genus Salvia are famous for having medicinal properties due to their chemical constituents. Salvia bucharica (Lamiacea) is found in Balochistan near Quetta in Hannaurak and Kalat. It is used in traditional system of medicine and claims to cure liver ailments. In current study crude methanolic extract (CME) of Salvia bucharica was obtained from the leaves and tested for hepatoprotective activity and possible toxicity in rabbits. Liver toxicity was induced in rabbits by administration of carbon tetra chloride (CCl4) and evaluated by biochemical tests and histopathology of tissues. In this study rabbits were divided in to 3 groups (5 rabbit in each group). Rabbits of group I (control) were administered only vehicle (0.9% sodium chloride) orally. Rabbits of group II were given CCl4 and group III were treated with CCl4 and S. bucharica CME orally. For hepatoprotective effect serum enzyme level and total protein level were calculated. Histopathology of liver sections of rabbits was also carried out to observe protective effect. Biochemical, hematological and histoptahological parameters were studied on rabbits for toxicological studies. S. bucharica CME showed significant liver protection with reduction in total bilirubin, direct bilirubin, Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), Alkaline phosphatase (ALP), gamma glutamyl transpeptidase (γ-GT). And decrease in Albumin and globulin. In toxicological studies, biochemical and histoptahological parameters showed no significant toxicity in liver, heart and kidneys. It is concluded that S. bucharica CME showed hepatoprotective effects with nontoxic profile.

  4. INFECTIOUS MYXOMATOSIS OF RABBITS

    PubMed Central

    Rivers, Thomas M.; Ward, S. M.

    1937-01-01

    From the results of the experiments described in this paper it is obvious that large amounts of elementary bodies of myxoma can be obtained in a relatively pure state by means of the methods used. Furthermore, it is evident that infectious myxomatosis is a viral disease in which elementary bodies of the same order of magnitude as vaccinal elementary bodies play a conspicuous rô1e in that they either represent the etiological agent or are intimately associated with it. The bodies are specifically agglutinated by antimyxoma serum and are agglutinated to a less extent by serum from rabbits convalescing from fibroma, a disease closely related to myxoma. In virus-free filtrates of emulsions prepared from infected skin there is a soluble precipitinogen or precipitinogens specific for the malady. Moreover, a specific precipitinogen or precipitinogens are demonstrable in virus-free serum of animals acutely ill as a result of extensive infection with myxoma virus. It is believed that this is the second viral disease, yellow fever (14) being the first, in which a specific soluble antigen free from virus has been found in the serum of ill animals. PMID:19870643

  5. Sustained eye closure slows saccades

    PubMed Central

    Shaikh, Aasef G.; Wong, Aaron L.; Optican, Lance M.; Miura, Kenichiro; Solomon, David; Zee, David S.

    2010-01-01

    Saccadic eye movements rapidly orient the line of sight towards the object of interest. Pre-motor burst neurons (BNs) controlling saccades receive excitation from superior colliculus and cerebellum, but inhibition by omnipause neurons (OPNs) prevents saccades. When the OPNs pause, BNs begin to fire. It has been presumed that part of the BN burst comes from post-inhibitory rebound (PIR). We hypothesized that in the absence of prior inhibition from OPNs there would be no PIR, and thus the increase in initial firing rate of BNs would be reduced. Consequently, saccade acceleration would be reduced. We measured eye movements and showed that sustained eye closure, which inhibits the activity of OPNs and thus hypothetically should weaken PIR, reduced the peak velocity, acceleration, and deceleration of saccades in healthy human subjects. Saccades under closed eyelids also had irregular trajectories; the frequency of the oscillations underlying this irregularity was similar to that of high-frequency ocular flutter (back-to-back saccades) often seen in normal subjects during attempted fixation at straight ahead while eyes are closed. Saccades and quick phases of nystagmus are generated by the same pre-motor neurons, and we found that the quick-phase velocity of nystagmus was also reduced by lid closure. These changes were not due to a mechanical hindrance to the eyes, because lid closure did not affect the peak velocities or accelerations of the eyes in the “slow-phase” response to rapid head movements of comparable speeds to those of saccades. These results indicate a role for OPNs in generating the abrupt onset and high velocities of saccades. We hypothesize that the mechanism involved is PIR in pre-motor burst neurons. PMID:20573593

  6. Late degeneration in rabbit tissues after irradiation by heavy ions

    NASA Technical Reports Server (NTRS)

    Lett, J. T.; Cox, A. B.; Keng, P. C.; Lee, A. C.; Su, C. M.; Bergtold, D. S.

    1980-01-01

    Results are presented for investigations of the late effects of heavy-ion irradiation on rabbit tissues which were undertaken to assess the hazards associated with the long-term exposure of humans to heavy ions in space during such activities as the construction of solar power stations or voyages to Mars. White rabbits approximately six weeks old were exposed to various doses of collimated beams of 400-MeV/n Ne ions, 570 MeV/n Ar ions and Co-60 gamma rays directed through both eyes, and the responses of the various tissues (hair follicles, skin, cornea, lens, retina, Harderian glands, bone and forebrain) were examined. Proliferating tissues are found to exhibit high damage levels in the early and late periods following irradiation, while terminally differentiating tissues repond to radiation most intensely in the late period, years after irradiation, with no intermediate recovery. The results obtained from rabbits are used to predict the occurrence of late tissue degeneration in the central nervous system, terminally differentiating systems and stem cells of humans one or more decades following exposure to radiation levels anticipated during long-duration space flights. The studies also indicate that tissues may be prematurely aged in the sense that tissue life spans may be shortened without the development of malignancies.

  7. Late degeneration in rabbit tissues after irradiation by heavy ions

    NASA Technical Reports Server (NTRS)

    Lett, J. T.; Cox, A. B.; Keng, P. C.; Lee, A. C.; Su, C. M.; Bergtold, D. S.

    1980-01-01

    Results are presented for investigations of the late effects of heavy-ion irradiation on rabbit tissues which were undertaken to assess the hazards associated with the long-term exposure of humans to heavy ions in space during such activities as the construction of solar power stations or voyages to Mars. White rabbits approximately six weeks old were exposed to various doses of collimated beams of 400-MeV/n Ne ions, 570 MeV/n Ar ions and Co-60 gamma rays directed through both eyes, and the responses of the various tissues (hair follicles, skin, cornea, lens, retina, Harderian glands, bone and forebrain) were examined. Proliferating tissues are found to exhibit high damage levels in the early and late periods following irradiation, while terminally differentiating tissues repond to radiation most intensely in the late period, years after irradiation, with no intermediate recovery. The results obtained from rabbits are used to predict the occurrence of late tissue degeneration in the central nervous system, terminally differentiating systems and stem cells of humans one or more decades following exposure to radiation levels anticipated during long-duration space flights. The studies also indicate that tissues may be prematurely aged in the sense that tissue life spans may be shortened without the development of malignancies.

  8. Biomechanical Measurement of Rabbit Cornea by a Modified Scheimpflug Device

    PubMed Central

    Zhang, Bo; Gu, Jianjun; Zhang, Xiaoxiao; Yang, Bin

    2016-01-01

    Purpose. To explore the probability and variation in biomechanical measurements of rabbit cornea by a modified Scheimpflug device. Methods. A modified Scheimpflug device was developed by imaging anterior segment of the model imitating the intact eye at various posterior pressures. The eight isolated rabbit corneas were mounted on the Barron artificial chamber and images of the anterior segment were taken at posterior pressures of 15, 30, 45, 60, and 75 mmHg by the device. The repeatability and reliability of the parameters including CCT, ACD, ACV, and CV were evaluated at each posterior pressure. All the variations of the parameters at the different posterior pressures were calculated. Results. All parameters showed good intraobserver reliability (Cronbach's alpha; intraclass correlation coefficient, α, ICC > 0.96) and repeatability in the modified Scheimpflug device. With the increase of posterior pressures, the ratio of CCT decreased linearly and the bulk modulus gradually reduced to a platform. The increase of ACD was almost linear with the posterior pressures elevated. Conclusions. The modified Scheimpflug device was a valuable tool to investigate the biomechanics of the cornea. The posterior pressure 15–75 mmHg range produced small viscoelastic deformations and nearly linear pressure-deformation response in the rabbit cornea. PMID:27446608

  9. Effects of X radiation on the retina of the albino rabbit as viewed with the scanning electron microscope

    SciTech Connect

    Newton, J.C.; Barsa-Newton, M.C.; Wardly, J.

    1980-02-01

    The eyes of albino rabbits were exposed in vivo to 7000 rad of X radiation, and the retinas were examined with a scanning electron microscope 24 and 72 h after irradiation. The rods and cones of the retina were observed to show the most severe damage.

  10. Benzalkonium Chloride Suppresses Rabbit Corneal Endothelium Intercellular Gap Junction Communication

    PubMed Central

    Zhang, Zhenhao; Huang, Yue; Xie, Hui; Pan, Juxin; Liu, Fanfei; Li, Xuezhi; Chen, Wensheng; Hu, Jiaoyue; Liu, Zuguo

    2014-01-01

    Purpose Gap junction intercellular communication (GJIC) plays a critical role in the maintenance of corneal endothelium homeostasis. We determined if benzalkonium chloride (BAK) alters GJIC activity in the rabbit corneal endothelium since it is commonly used as a drug preservative in ocular eyedrop preparations even though it can have cytotoxic effects. Methods Thirty-six adult New Zealand albino rabbits were randomly divided into three groups. BAK at 0.01%, 0.05%, and 0.1% was applied twice daily to one eye of each of the rabbits in one of the three groups for seven days. The contralateral untreated eyes were used as controls. Corneal endothelial morphological features were observed by in vivo confocal microscopy (IVCM). Immunofluorescent staining resolved changes in gap junction integrity and localization. Western blot analysis and RT-PCR evaluated changes in levels of connexin43 (Cx43) and tight junction zonula occludens-1 (ZO-1) gene and protein expression, respectively. Cx43 and ZO-1 physical interaction was detected by immunoprecipitation (IP). Primary rabbit corneal endothelial cells were cultured in Dulbecco's Modified Eagle Medium (DMEM) containing BAK for 24 hours. The scrape-loading dye transfer technique (SLDT) was used to assess GJIC activity. Results Topical administration of BAK (0.05%, 0.1%) dose dependently disrupted corneal endothelial cell morphology, altered Cx43 and ZO-1 distribution and reduced Cx43 expression. BAK also markedly induced increases in Cx43 phosphorylation status concomitant with decreases in the Cx43-ZO-1 protein-protein interaction. These changes were associated with marked declines in GJIC activity. Conclusions The dose dependent declines in rabbit corneal endothelial GJIC activity induced by BAK are associated with less Cx43-ZO-1 interaction possibly arising from increases in Cx43 phosphorylation and declines in its protein expression. These novel changes provide additional evidence that BAK containing eyedrop preparations

  11. RABBIT ANTIBODIES TO STREPTOCOCCAL CARBOHYDRATES

    PubMed Central

    Braun, Dietmar G.; Eichmann, Klaus; Krause, Richard M.

    1969-01-01

    In a search for possible genetic factors which may influence the immune response to the streptococcal carbohydrates, over 100 rabbits have been immunized with streptococcal vaccines, and representative examples of high and low response pairs mated. The concentration of precipitins to the group—specific carbohydrates has been measured in the antisera following primary intravenous immunization with heat-killed streptococcal vaccines, Group A, Group A-variant, and Group C. For the majority of rabbits, the concentration of precipitins varied between 1 and 10 mg/ml of antiserum; while in the minority, it was between 11 and 32 mg/ml. The offspring of rabbits with high antibody levels had a significantly higher concentration of antibody than was seen in the offspring of rabbits of low response parents. Such data suggest that the magnitude of the immune response to these carbohydrate antigens is under some form of genetic control. Not uncommonly in rabbits with hyper-γ-globulinemia following primary immunization, the group-specific precipitins are the predominant component of the γ-globulin. An unusual feature of such components is that they are electrophoretically monodisperse, and possess individual antigenic specificity. In this respect they resemble the myeloma proteins. When a response of this sort is not seen after primary immunization, it may occur after secondary immunization. Therefore, prior exposure to the same or closely related antigen may also have an influence on the occurrence of high concentrations of such uniform antibodies. PMID:5766948

  12. Eye irritation study of some pesticides on chorioallantoic membrane of the egg.

    PubMed

    Kormos, E; Tavaszi, J; Budai, P; Pongrácz, A; Lehel, J

    2009-01-01

    The chorioallantoic membrane of chick embryo has been used extensively for many years in various fields of biological research, including virology, bacteriology and toxicology. The chorioallantoic membrane (CAM) is a complete tissue that responds to injury with a complete inflammatory reaction, this process similar to that induced by chemicals in the conjunctival tissue of the rabbit eye. A possible model for assessing the irritation potential of a chemical or product to such a vascularised tissue is the choriallantoic membrane of the embryonated hen's egg, as this is a highly vascular, thin membrane with relatively easy access for both treatment and assessment. In recent years various in vitro methods have been developed to replace the heavily criticized Draize rabbit eye test for irritation testing. One of the most studied alternative methods is the Hen's Egg Test - Chorioallantoic membrane (HET-CAM). In our studies a comparative screening was done with a set of pesticides to establish parallel data on in vitro (HET-CAM) and in vivo (Draize) results. In most cases good correlation was found between the HET-CAM assessment and results from the Draize rabbit eye test. The actual form of the HET-CAM test is a valuable pre-screen for predicting ocular irritation potential of chemicals, and can be used to reduce the number of experimental animals. The HET-CAM test is useful as a part of a battery of tests to replace the Draize rabbit eye test.

  13. [Functional alterations in the retina following a 10 Gy gamma irradiation localized in the eye].

    PubMed

    Bagot, J D; Courant, D; Court, L

    1980-11-17

    A single-eye irradiation of 10 Gy (0.8 Gy. min-1) induces impairments of the electrical responses of the rabbit retina in dark adaptation. These are associated with reversible alteration of the photoreceptors and the preganglionic neurons and a disturbance of all the mechanisms of adaptation. Possible relationships between these functional alterations and the effects of irradiation are discussed.

  14. Fetal Eye Movements on Magnetic Resonance Imaging

    PubMed Central

    Woitek, Ramona; Kasprian, Gregor; Lindner, Christian; Stuhr, Fritz; Weber, Michael; Schöpf, Veronika; Brugger, Peter C.; Asenbaum, Ulrika; Furtner, Julia; Bettelheim, Dieter; Seidl, Rainer; Prayer, Daniela

    2013-01-01

    Objectives Eye movements are the physical expression of upper fetal brainstem function. Our aim was to identify and differentiate specific types of fetal eye movement patterns using dynamic MRI sequences. Their occurrence as well as the presence of conjugated eyeball motion and consistently parallel eyeball position was systematically analyzed. Methods Dynamic SSFP sequences were acquired in 72 singleton fetuses (17–40 GW, three age groups [17–23 GW, 24–32 GW, 33–40 GW]). Fetal eye movements were evaluated according to a modified classification originally published by Birnholz (1981): Type 0: no eye movements; Type I: single transient deviations; Type Ia: fast deviation, slower reposition; Type Ib: fast deviation, fast reposition; Type II: single prolonged eye movements; Type III: complex sequences; and Type IV: nystagmoid. Results In 95.8% of fetuses, the evaluation of eye movements was possible using MRI, with a mean acquisition time of 70 seconds. Due to head motion, 4.2% of the fetuses and 20.1% of all dynamic SSFP sequences were excluded. Eye movements were observed in 45 fetuses (65.2%). Significant differences between the age groups were found for Type I (p = 0.03), Type Ia (p = 0.031), and Type IV eye movements (p = 0.033). Consistently parallel bulbs were found in 27.3–45%. Conclusions In human fetuses, different eye movement patterns can be identified and described by MRI in utero. In addition to the originally classified eye movement patterns, a novel subtype has been observed, which apparently characterizes an important step in fetal brainstem development. We evaluated, for the first time, eyeball position in fetuses. Ultimately, the assessment of fetal eye movements by MRI yields the potential to identify early signs of brainstem dysfunction, as encountered in brain malformations such as Chiari II or molar tooth malformations. PMID:24194885

  15. Fetal eye movements on magnetic resonance imaging.

    PubMed

    Woitek, Ramona; Kasprian, Gregor; Lindner, Christian; Stuhr, Fritz; Weber, Michael; Schöpf, Veronika; Brugger, Peter C; Asenbaum, Ulrika; Furtner, Julia; Bettelheim, Dieter; Seidl, Rainer; Prayer, Daniela

    2013-01-01

    Eye movements are the physical expression of upper fetal brainstem function. Our aim was to identify and differentiate specific types of fetal eye movement patterns using dynamic MRI sequences. Their occurrence as well as the presence of conjugated eyeball motion and consistently parallel eyeball position was systematically analyzed. Dynamic SSFP sequences were acquired in 72 singleton fetuses (17-40 GW, three age groups [17-23 GW, 24-32 GW, 33-40 GW]). Fetal eye movements were evaluated according to a modified classification originally published by Birnholz (1981): Type 0: no eye movements; Type I: single transient deviations; Type Ia: fast deviation, slower reposition; Type Ib: fast deviation, fast reposition; Type II: single prolonged eye movements; Type III: complex sequences; and Type IV: nystagmoid. In 95.8% of fetuses, the evaluation of eye movements was possible using MRI, with a mean acquisition time of 70 seconds. Due to head motion, 4.2% of the fetuses and 20.1% of all dynamic SSFP sequences were excluded. Eye movements were observed in 45 fetuses (65.2%). Significant differences between the age groups were found for Type I (p = 0.03), Type Ia (p = 0.031), and Type IV eye movements (p = 0.033). Consistently parallel bulbs were found in 27.3-45%. In human fetuses, different eye movement patterns can be identified and described by MRI in utero. In addition to the originally classified eye movement patterns, a novel subtype has been observed, which apparently characterizes an important step in fetal brainstem development. We evaluated, for the first time, eyeball position in fetuses. Ultimately, the assessment of fetal eye movements by MRI yields the potential to identify early signs of brainstem dysfunction, as encountered in brain malformations such as Chiari II or molar tooth malformations.

  16. Five-year results of corneal tattooing for cosmetic repair in disfigured eyes.

    PubMed

    Kim, Cinoo; Kim, Keun Ho; Han, Young Keun; Wee, Won Ryang; Lee, Jin Hak; Kwon, Ji-Won

    2011-10-01

    To investigate the 5-year results of corneal tattooing for cosmetic repair in disfigured eyes and identify the risk factors associated with complications. Corneal tattooing was performed in patients with stable corneal opacity and blind eyes. A total of 147 eyes of 147 patients who were followed up for at least 5 years after tattooing were enrolled in the study. The following valuables were included as potential risk factors for long-term complications: age, sex, duration of opacity before tattooing, and the presence of calcific plaque. Corneal tattooing was also performed in 6 rabbit eyes, and the stained eyes were enucleated at 6 months postoperatively for histological analysis. The average follow-up time after surgery was 65 ± 5 months. Long-term complications such as reopacification or increased opacity, fading of color, and epithelial growth developed in 12% of the tattooed eyes between 2 and 4 years after surgery and most required reoperation. Univariate analysis of risk factors affecting recurrence or complications revealed no statistically significant differences among candidate factors. Histological results of the tattooed rabbit eyes showed that clumps of blackish granules were present in the anterior half of the stroma without any infiltration of inflammatory cells to the adjacent layers. Corneal tattooing in disfigured eyes provided a good cosmetic outcome more than 5 years after surgery.

  17. Training the Eyes for Competition: Fighting Eyes.

    ERIC Educational Resources Information Center

    Williams, Darrell; Bradford, Vincent

    1989-01-01

    Fencers should be taught to discipline their eyes to focus on the opponent's hand. The rationale for this strategy as well as drills to develop "hand watching" skills are presented in this article. (IAH)

  18. Intravitreal toxicity of dental adhesives in the rabbit.

    PubMed

    Ciulla, T A; Haimovici, R; Riley, E J; D'Amico, D J

    1996-01-01

    The authors tested the intravitreal toxicity of four commonly employed dental adhesives to determine their suitability as retinal adhesives. Two glass ionomers, a polycarboxylate, and a composite resin (Ketac-Bond Radiopaque Poly Maleic Acid [ESPE, Oberbay, Germany], Vitrebond Light Cure Glass Ionomer [3M, St. Paul, MN], Carbchem Zinc Polycarboxylate Cement [PSP Dental Company, Kent, United Kingdom], and Kerr Porcelite Dual Cure [Kerr, Romulus, MI]) were reconstituted according to the manufacturer's recommendations, and 0.1 mliter was injected separately into the vitreous cavity of New Zealand white rabbits. Serial slit-lamp and funduscopic evaluations were performed up to 3 months after injection. Selected eyes were studied angiographically and histopathologically. Intravitreal administration of the glass ionomers Ketac-bond or Vitrebond lead to intense vitritis within the first weeks. Necrotic retinal detachments ultimately developed in these eyes, along with those administered the polycarboxylate cement Carbchem. Eyes injected with the composite resin Porcelite Dual Cure showed no ophthalmoscopic evidence of vitreous or retinal toxicity and no angiographic evidence of vascular toxicity. Histopathology of the eyes with this intravitreal composite resin cement revealed mild disorganization of photoreceptor nuclei and outer segments. Among the agents studied, the dual-cure composite resin cement Porcelite showed the least ocular toxicity. Further studies to evaluate its intraocular toxicity and efficacy as a retinal adhesive are warranted.

  19. Evolutionary morphology of the rabbit skull

    PubMed Central

    Sherratt, Emma

    2016-01-01

    The skull of leporids (rabbits and hares) is highly transformed, typified by pronounced arching of the dorsal skull and ventral flexion of the facial region (i.e., facial tilt). Previous studies show that locomotor behavior influences aspects of cranial shape in leporids, and here we use an extensive 3D geometric morphometrics dataset to further explore what influences leporid cranial diversity. Facial tilt angle, a trait that strongly correlates with locomotor mode, significantly predicts the cranial shape variation captured by the primary axis of cranial shape space, and describes a small proportion (13.2%) of overall cranial shape variation in the clade. However, locomotor mode does not correlate with overall cranial shape variation in the clade, because there are two district morphologies of generalist species, and saltators and cursorial species have similar morphologies. Cranial shape changes due to phyletic size change (evolutionary allometry) also describes a small proportion (12.5%) of cranial shape variation in the clade, but this is largely driven by the smallest living leporid, the pygmy rabbit (Brachylagus idahoensis). By integrating phylogenetic history with our geometric morphometric data, we show that the leporid cranium exhibits weak phylogenetic signal and substantial homoplasy. Though these results make it difficult to reconstruct what the ‘ancestral’ leporid skull looked like, the fossil records suggest that dorsal arching and facial tilt could have occurred before the origin of the crown group. Lastly, our study highlights the diversity of cranial variation in crown leporids, and highlights a need for additional phylogenetic work that includes stem (fossil) leporids and includes morphological data that captures the transformed morphology of rabbits and hares. PMID:27688967

  20. Corneal wound healing following laser in situ keratomileusis (LASIK): a histopathological study in rabbits

    PubMed Central

    Kato, T.; Nakayasu, K.; Hosoda, Y.; Watanabe, Y.; Kanai, A.

    1999-01-01

    AIMS—To investigate the histopathological changes of rabbit corneas after laser in situ keratomileusis (LASIK) and to evaluate the corneal wound healing process.
METHODS—A LASIK was performed on white rabbit eyes. Postoperatively, rabbits were killed on days 1 and 7, and at 1, 3, and 9 months.
RESULTS—Periodic acid Schiff (PAS) positive material and disorganised collagen fibre were seen along the interface of the corneal flap even 9 months after operation.
CONCLUSIONS—The wound healing process still continued at 9 months after LASIK indicating that a much longer time than expected was required for corneal wound healing following LASIK.

 PMID:10535863

  1. Norfloxacin and silver norfloxacin in the treatment of Pseudomonas corneal ulcer in the rabbit.

    PubMed Central

    Darrell, R W; Modak, S M; Fox, C L

    1984-01-01

    Norfloxacin is a new synthetic antibiotic with a broad spectrum of activity against gram-positive and gram-negative bacteria, and is more effective than the aminoglycosides against P aeruginosa. In this study norfloxacin was particularly effective in treatment of P aeruginosa infection of the rabbit cornea, and caused no toxicity in normal rabbit eyes after prolonged administration. The addition of silver to norfloxacin enhances its antipseudomonal activity, and broadens its spectrum to include antifungal activity. In this study, silver norfloxacin appears to be the most effective antibiotic against P aeruginosa corneal ulcer in the rabbit. Because of its broad antibacterial spectrum, silver norfloxacin may be useful in the initial treatment of bacterial corneal ulcer before the identity of the bacteria is known. Because of its low toxicity in topical administration, and its antifungal and antibacterial activity, silver norfloxacin may be helpful in prophylaxis against infection in chronic corneal ulcers. Images FIGURE 1 FIGURE 2 FIGURE 3 PMID:6242083

  2. Ventral rhinotomy in a pet rabbit (Oryctolagus cuniculus) with an odontogenic abscess and sub-obstructive rhinitis

    PubMed Central

    Brown, Tamara; Beaufrère, Hugues; Brisson, Brigitte; Laniesse, Delphine; zur Linden, Alex

    2016-01-01

    A rabbit was presented for severe dyspnea and was diagnosed with an odontogenic abscess obstructing the rostral nasopharynx using CT scan and oral endoscopy. The offending tooth was extracted intraorally, but due to persistent dyspnea, an endoscopic-guided ventral rhinotomy was performed. The dyspnea subsequently resolved, but the rabbit died 5 weeks later from a seemingly unrelated cause. PMID:27493289

  3. Ventral rhinotomy in a pet rabbit (Oryctolagus cuniculus) with an odontogenic abscess and sub-obstructive rhinitis.

    PubMed

    Brown, Tamara; Beaufrère, Hugues; Brisson, Brigitte; Laniesse, Delphine; Zur Linden, Alex

    2016-08-01

    A rabbit was presented for severe dyspnea and was diagnosed with an odontogenic abscess obstructing the rostral nasopharynx using CT scan and oral endoscopy. The offending tooth was extracted intraorally, but due to persistent dyspnea, an endoscopic-guided ventral rhinotomy was performed. The dyspnea subsequently resolved, but the rabbit died 5 weeks later from a seemingly unrelated cause.

  4. Bevacizumab application delays epithelial healing in rabbit cornea.

    PubMed

    Kim, Tae-im; Chung, Jae Lim; Hong, Jin Pyo; Min, Kyung; Seo, Kyoung Yul; Kim, Eung Kweon

    2009-10-01

    Vascular endothelial growth factor (VEGF) is essential for neovascularization, but the use of anti-VEGF therapies to inhibit neovascularization may influence epithelial wound healing. Here, the effects of bevacizumab on corneal epithelial wound healing time in rabbit models, cell proliferation, and expression of integrins in human corneal epithelial and fibroblast cells were evaluated. To compare epithelial wound healing times, epithelial defect sizes were measured after application of bevacizumab topical eye drops at 0, 0.5, 1.0, 1.5, 2.5, or 5 mg/mL, twice daily, to mechanically debrided epithelia of rabbit corneas. The cellular covering of wounded areas and expression of Ki67 were assessed after scrape injuries in cultures of human corneal epithelial and fibroblast cells. Expression of cell surface integrins and collagens was measured using plates coated with mouse monoclonal antibodies against human adhesion molecules, and relevant mRNA levels were assessed by reverse-transcription-polymerase chain reaction (RT-PCR). The application of bevacizumab topical eye drops at 1.0, 1.5, 2.5, or 5 mg/mL delayed rabbit corneal epithelial healing. Cell cultures growing under high concentrations of bevacizumab showed delay in the proliferation of corneal epithelial and fibroblast cells. Surface expression of mRNA encoding integrins and collagens were decreased by 1.5 mg/mL of bevacizumab. Bevacizumab delayed corneal epithelial wound healing and inhibited integrin expression. When bevacizumab is used to reduce the development of new corneal vessels, slight delays in epithelial wound healing are possible and cellular proliferation is to be expected.

  5. [Eye irritation and chemical eye burns. Review of experimental and clinical studies].

    PubMed

    Cordes, A K; Frentz, M; Schrage, N F

    2011-10-01

    Chemical burns of the