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1.
Int J Mol Sci ; 22(21)2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34769100

RESUMEN

After successful surgeries for patients with rhegmatogenous retinal detachment, the most common cause of retinal redetachment is proliferative vitreoretinopathy (PVR), which causes severe vision impairment and even blindness worldwide. Until now, the major treatment for PVR is surgical removal of the epiretinal membrane, while effective treatment to prevent PVR is still unavailable. Therefore, we investigated the potential of doxycycline, an antibiotic in the tetracycline class, to treat PVR using a mouse model. We used the human retinal pigment epithelial cell line, ARPE-19, for in vitro and in vivo studies to test doxycycline for PVR treatment. We found that doxycycline suppressed the migration, proliferation, and contraction of ARPE-19 cells with reduced p38 MAPK activation and total MMP activity. Intravitreal doxycycline and topical tetracycline treatment significantly ameliorated the PVR severity induced by ARPE-19 cells in mice. PVR increased the expression of MMP-9 and IL-4 and p38 MAPK phosphorylation and modestly decreased IL-10. These effects were reversed by doxycycline and tetracycline treatment in the mouse retina. These results suggest that doxycycline will be a potential treatment for PVR in the future.


Asunto(s)
Antibacterianos/administración & dosificación , Doxiciclina/administración & dosificación , Vitreorretinopatía Proliferativa/tratamiento farmacológico , Animales , Línea Celular , Quimiocina CXCL9/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Inyecciones Intravítreas , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones Endogámicos C57BL , Retina/efectos de los fármacos , Retina/enzimología , Vitreorretinopatía Proliferativa/metabolismo , Cuerpo Vítreo/efectos de los fármacos , Cuerpo Vítreo/enzimología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
2.
Retin Cases Brief Rep ; 15(2): 97-100, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30048404

RESUMEN

PURPOSE: To report treatment of vitreous seeding of choroidal melanoma with monthly injections of intravitreal melphalan. METHODS: Case report. RESULTS: A 70-year-old white woman noted floaters in her left eye, and further examination revealed visual acuity of 20/30 in both eyes. Funduscopically, there was a mushroom-shaped choroidal melanoma in her left eye, measuring 9 mm in basal dimension and 4.8 mm in thickness. Notably, there was apical retinal invasion of melanoma with mild vitreous hemorrhage, without vitreous seeding. The tumor was treated with iodine-125 plaque radiotherapy using an apex dose of 70 Gy over 99 hours, designed to include the retinal invasion. The melanoma demonstrated complete regression into a nearly flat scar of 1 mm and remained stable over 4 years. Five years after radiotherapy, there were diffuse vitreous pigmented seeds of presumed melanoma origin, emanating from the site of retinal necrosis. This progressively worsened over the following 18 months, suspicious for viable melanoma cells, as visual acuity concurrently declined to 20/100. Treatment with intravitreal melphalan (10 µg/0.05 mL) was delivered on a monthly basis for 12 cycles, resulting in vitreous seeds regression, and preservation of the eye. Final visual acuity was 20/200. There were no treatment-related complications. CONCLUSION: Intravitreal melphalan can be considered in cases of vitreous seeding from uveal melanoma.


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Neoplasias de la Coroides/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Melfalán/uso terapéutico , Siembra Neoplásica , Neoplasias de la Retina/tratamiento farmacológico , Cuerpo Vítreo/efectos de los fármacos , Anciano , Neoplasias de la Coroides/diagnóstico por imagen , Neoplasias de la Coroides/patología , Femenino , Angiografía con Fluoresceína , Humanos , Inyecciones Intravítreas , Melanoma/diagnóstico por imagen , Melanoma/secundario , Neoplasias de la Retina/diagnóstico por imagen , Neoplasias de la Retina/secundario , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Cuerpo Vítreo/patología
3.
Eur J Pharm Biopharm ; 153: 130-149, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32445965

RESUMEN

The majority of blinding conditions arise due to chronic pathologies in the retina. During the last two decades, antibody-based medicines administered by intravitreal injection directly into the back of the eye have revolutionised the treatment of chronic retinal diseases characterised by uncontrolled blood vessel growth, e.g. wet age-related macular degeneration (wAMD), diabetic retinopathy (DR) and choroidal neovascularisation (CNV). Although intravitreal injections have become a commonly performed ophthalmic procedure that provides a reproducible dose to maximise drug exposure in the back of the eye, there is a need to minimise the frequency and cumulative number of intravitreal injections. Developing longer acting intraocular therapies is one key strategy that is being pursued. Pharmaceutical preclinical development of intraocular medicines is heavily reliant on the use of animal models to determine ocular tolerability, pharmacokinetics, biodistribution and drug stability. Animal eyes are different from human eyes, such as the anatomy, organisation of vitreous macromolecular structure, aqueous outflow and immune response; all which impacts the ability to translate preclinical data into a clinical product. The development of longer acting protein formulations using animals is also limited because animals reject human proteins. Preclinical strategies also do not account for differences in the vitreous due to ageing and whether a vitrectomy has been performed. Intraocular formulations must reside and clear from the vitreous body, so there is a need for the formulation scientist to have knowledge about vitreous structure and physiology to facilitate preclinical development strategies. Preclinical pharmaceutical development paradigms used to create therapies for other routes of administration (e.g. oral, subcutaneous, pulmonary and intravenous) are grounded on the use of preclinical in vitro models. Analogous pharmaceutical strategies with appropriately designed in vitro models that can account for intraocular mass transfer to estimate pharmacokinetic profiles can be used to develop in vitro-in vivo correlations (IVIVCs) to accelerate the preclinical optimisation of long-acting intraocular formulations. Data obtained can then inform preclinical in vivo and clinical studies. With the now widespread use of intravitreal injections, it is also important during early preclinical studies to ensure there is a viable regulatory pathway for new therapies. Knowledge of the physiological, pharmaceutical and regulatory factors will help in the development of long-acting intravitreal medicines, which is rapidly evolving into a distinct pharmaceutical discipline.


Asunto(s)
Preparaciones Farmacéuticas/administración & dosificación , Preparaciones Farmacéuticas/química , Animales , Química Farmacéutica/métodos , Neovascularización Coroidal/tratamiento farmacológico , Retinopatía Diabética/tratamiento farmacológico , Sistemas de Liberación de Medicamentos/métodos , Evaluación Preclínica de Medicamentos , Humanos , Inyecciones Intravítreas/métodos , Degeneración Macular/tratamiento farmacológico , Retina/efectos de los fármacos , Enfermedades de la Retina/tratamiento farmacológico , Distribución Tisular/fisiología , Cuerpo Vítreo/efectos de los fármacos
4.
Invest Ophthalmol Vis Sci ; 58(4): 2167-2179, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28399267

RESUMEN

Purpose: The aim of the present study was to evaluate the utility of the relatively hydrophilic Δ9-tetrahydrocannabinol (THC) prodrugs, mono and di-valine esters (THC-Val and THC-Val-Val) and the amino acid (valine)-dicarboxylic acid (hemisuccinate) ester (THC-Val-HS), with respect to ocular penetration and intraocular pressure (IOP) lowering activity. THC, timolol, and pilocarpine eye drops were used as controls. Methods: THC-Val, THC-Val-Val, and THC-Val-HS were synthesized and chemically characterized. Aqueous solubility and in vitro transcorneal permeability of THC and the prodrugs, in the presence of various surfactants and cyclodextrins, were determined. Two formulations were evaluated for therapeutic activity in the α-chymotrypsin induced rabbit glaucoma model, and the results were compared against controls comprising of THC emulsion and marketed timolol maleate and pilocarpine eye drops. Results: THC-Val-HS demonstrated markedly improved solubility (96-fold) and in vitro permeability compared to THC. Selected formulations containing THC-Val-HS effectively delivered THC to the anterior segment ocular tissues in the anesthetized rabbits: 62.1 ng/100 µL of aqueous humor (AH) and 51.4 ng/50 mg of iris ciliary bodies (IC) (total THC). The duration and extent of IOP lowering induced by THC-Val-HS was 1 hour longer and 10% greater, respectively, than that obtained with THC and was comparable with the pilocarpine eye drops. Timolol ophthalmic drops, however, exhibited a longer duration of activity. Both THC and THC-Val-HS were detected in the ocular tissues following multiple dosing of THC-Val-HS in conscious animals. The concentration of THC in the iris-ciliary bodies at the 60- and 120-minute time points (53 and 57.4 ng/50 mg) were significantly greater than that of THC-Val-HS (24.2 and 11.3 ng/50 mg). Moreover, at the two time points studied, the concentration of THC was observed to increase or stay relatively constant, whereas THC-Val-HS concentration decreased by at least 50%. A similar trend was observed in the retina-choroid tissues. Conclusions: A combination of prodrug derivatization and formulation development approaches significantly improved the penetration of THC into the anterior segment of the eye following topical application. Enhanced ocular penetration resulted in significantly improved IOP-lowering activity.


Asunto(s)
Humor Acuoso/metabolismo , Córnea/metabolismo , Dronabinol/farmacocinética , Glaucoma/tratamiento farmacológico , Presión Intraocular/efectos de los fármacos , Profármacos/farmacocinética , Cuerpo Vítreo/metabolismo , Animales , Humor Acuoso/efectos de los fármacos , Disponibilidad Biológica , Agonistas de Receptores de Cannabinoides/farmacocinética , Córnea/efectos de los fármacos , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Glaucoma/metabolismo , Glaucoma/fisiopatología , Masculino , Soluciones Oftálmicas , Conejos , Cuerpo Vítreo/efectos de los fármacos
5.
J Nutr Biochem ; 26(11): 1357-67, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26362107

RESUMEN

Green tea extract (GTE) exerts antioxidative activities in ocular tissues of rats, but high levels of (-)-epigallocatechin gallate (EGCG) can induce oxidative stress. In this study, pharmacokinetics, diurnal variation of oxidative status, antioxidation and transcription factors changes in ocular tissues of rats were investigated. Rats were fed intragastrically with GTE and catechin mixtures containing different amounts of EGCG. Plasma and various ocular tissues were taken for pharmacokinetic analysis, oxidation marker testings and gene expression assays. Effects of EGCG on ocular oxidation status were assessed by 8-isoprostane level and reduced/oxidized glutathione ratio. Oxidation, inflammation and apoptosis regulations in retina were evaluated by real-time polymerase chain reaction. Epicatechin, epigallocatechin and EGCG were dominant in various ocular tissues except vitreous humor, where gallocatechin was predominant. Diurnal variation of oxidative status was found in some compartments. GTE caused oxidative stress increase in the plasma, aqueous humor, vitreous humor, cornea and retina but decrease in the lens and choroid-sclera. Catechins mixture containing half dose of EGCG lowered 8-isoprostane in the retina and lens. GTE treatment induced superoxide dismutase 1 and glutathione peroxidase-3 expressions but suppressed catalase in the retina. Our results reveal pro-oxidation of GTE with high EGCG content to the ocular tissues. Optimal EGCG level is needed for protection.


Asunto(s)
Apoptosis/genética , Catequina/análogos & derivados , Endoftalmitis/genética , Té/química , Animales , Antiinflamatorios no Esteroideos/farmacología , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Catequina/sangre , Catequina/farmacocinética , Catequina/farmacología , Relación Dosis-Respuesta a Droga , Endoftalmitis/dietoterapia , Ojo/efectos de los fármacos , Ojo/fisiopatología , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Ratas Sprague-Dawley , Cuerpo Vítreo/efectos de los fármacos
6.
Retina ; 35(6): 1128-34, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25635575

RESUMEN

PURPOSE: After the recent approval of ocriplasmin by the Food and Drug Administration, postmarketing safety concerns have been raised by the vitreoretinal community. The American Society of Retina Specialists Therapeutic Surveillance Committee was commissioned to monitor postmarketing drug-related and device-related adverse events. The purpose of this report is to analyze the postmarketing safety experience in the context of available premarketing safety data. METHODS: Periodic aggregate safety reports consisting of premarketing, or clinical trial, data (n = 999 injections) and postmarketing reports through July 16, 2013 (n = 4,387 injections), were retrospectively analyzed by the TSC. The aggregate data were analyzed to classify adverse events, and the postmarketing safety data for each event type were compared with the premarketing data. RESULTS: Eight categories of adverse events were identified. Acute reduction in visual acuity attributable to either worsening of macular pathology or development of subretinal fluid, electroretinogram changes, dyschromatopsia, retinal tears and detachments, lens subluxation or phacodonesis, impaired pupillary reflex, and retinal vessel findings were reported in both the premarketing and postmarketing experiences. Ellipsoid zone (inner segment/outer segment) findings were only reported in the postmarketing experience. Rates of postmarketing reports were lower than in the premarketing data. Adverse events were generally transient, and characteristics of these adverse events were generally similar between the premarketing and postmarketing experience. CONCLUSION: Postmarket analyses are limited by significant underreporting, and in the case of ocriplasmin as a first in-class drug, they may not have captured safety events that have only more recently been identified. Nonetheless, postmarket analyses can identify the scope of potential safety events based on real-world experiences. Ocriplasmin administration should be guided by an appropriate and informed risk-benefit discussion with the patient. Ongoing active postmarket surveillance by all practitioners will continue to be critical to better understand this safety profile.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/etiología , Oftalmopatías/tratamiento farmacológico , Fibrinolisina/efectos adversos , Fibrinolíticos/efectos adversos , Fragmentos de Péptidos/efectos adversos , Vigilancia de Productos Comercializados , Enfermedades de la Retina/tratamiento farmacológico , Cuerpo Vítreo/efectos de los fármacos , Ensayos Clínicos como Asunto , Defectos de la Visión Cromática/inducido químicamente , Evaluación Preclínica de Medicamentos , Electrorretinografía/efectos de los fármacos , Fibrinolisina/uso terapéutico , Fibrinolíticos/uso terapéutico , Humanos , Inyecciones Intravítreas , Subluxación del Cristalino/inducido químicamente , Fragmentos de Péptidos/uso terapéutico , Células Fotorreceptoras de Vertebrados/efectos de los fármacos , Células Fotorreceptoras de Vertebrados/patología , Reflejo Pupilar/efectos de los fármacos , Desprendimiento de Retina/inducido químicamente , Perforaciones de la Retina/inducido químicamente , Estudios Retrospectivos , Adherencias Tisulares/tratamiento farmacológico , Agudeza Visual/efectos de los fármacos
7.
Cutan Ocul Toxicol ; 34(4): 265-70, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25373486

RESUMEN

CONTEXT: Intravitreal (ITV) dosing has become a clinically important route of administration for the treatment of uveitis, endophthalmitis, retinal vein occlusion, diabetic macular edema and age-related macular degeneration. Despite this, there are no validated non-clinical models of phototoxicity for ITV products. OBJECTIVE: The objective of this study was to develop an ITV rabbit model of phototoxicity for use in assessing the photosafety of small molecules therapeutics. MATERIALS AND METHODS: Dutch Belted rabbits were intravitreally injected bilaterally with four known phototoxicants: 8-methoxypsoralen, lomefloxacin, doxycycline and stannsoporfrin. Triescence(®), a non-phototoxic triamcinolone acetonide steroid formulation designed for ITV administration, was used as a negative control. One eye was then irradiated with solar-simulated ultraviolet radiation for 30 min, 1 h after dosing, while the other eye was occluded, serving as a non-irradiated control. RESULTS: Despite the direct administration of known phototoxicants into the vitreous, no evidence of ocular phototoxicity was observed in any dose group. Direct (non-phototoxic) retinal toxicity was observed in the doxycycline dose group only. CONCLUSION: These data suggest that the posterior segment of the rabbit eye is protected against phototoxicity by anatomical and/or physiological mechanisms, and is not a useful model for the assessment of phototoxicity of intravitreally administered molecules.


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Bibliotecas de Moléculas Pequeñas/toxicidad , Pruebas de Toxicidad/métodos , Cuerpo Vítreo/efectos de los fármacos , Animales , Doxiciclina/toxicidad , Fluoroquinolonas/toxicidad , Inyecciones Intravítreas , Masculino , Metaloporfirinas/toxicidad , Metoxaleno/toxicidad , Conejos
8.
J Pharm Biomed Anal ; 102: 346-52, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25459934

RESUMEN

Ocular toxoplasmosis may result in uveitis in the posterior segment of the eye, leading to severe visual complications. Clindamycin-loaded poly(lactide-co-glycolide) (PLGA) implants could be applied to treat the ocular toxoplasmosis. In this study, the pharmacokinetic profiles of the drug administrated by PLGA implants and by intravitreal injections in rabbits' eyes were evaluated. The implant released the drug for 6 weeks while the drug administrated by intravitreal injections remained in the vitreous cavity for 2 weeks. Compared to the injected drug, the implants containing clindamycin had higher values of area under the curve (AUC) (39.2 vs 716.7 ng week mL(-1)) and maximum vitreous concentration (Cmax) (8.7 vs 13.83 ng mL(-1)). The implants prolonged the delivery of clindamycin and increased the contact of the drug with the eyes' tissues. Moreover, the in vivo ocular biocompatibility of the clindamycin-loaded PLGA implants was evaluated regarding to the clinical examination of the eyes and the measurement of the intraocular pressure (IOP) during 6 weeks. The implantable devices caused no ocular inflammatory process and induced the increase of the IOP in the fourth week of the study. The IOP augmentation could be related to the maximum concentration of clindamycin released from the implants. In conclusion, the PLGA implants based on clindamycin may be a therapeutic alternative to treat ocular toxoplasmosis.


Asunto(s)
Clindamicina/análisis , Clindamicina/farmacocinética , Ensayo de Materiales/métodos , Espectrometría de Masas en Tándem/métodos , Cuerpo Vítreo/química , Animales , Cromatografía Liquida/métodos , Clindamicina/química , Evaluación Preclínica de Medicamentos/métodos , Implantes de Medicamentos , Ojo/química , Ojo/efectos de los fármacos , Inyecciones Intravítreas , Masculino , Conejos , Cuerpo Vítreo/efectos de los fármacos
9.
Int J Food Sci Nutr ; 65(2): 235-40, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24059688

RESUMEN

The influence of a prolonged diet supplemented with the powerful antioxidant verbascoside on the oxidative state of 20 healthy hares eye fluids and tissues has been studied. Verbascoside was dosed at 2, 3, 4 mg/die and the impact on the oxidative state of ocular tissues and fluids was tested by TBARS (thio barbituric acid reactive substances) and TEAC (trolox equivalent antioxidant capacity) assays. The percentage of change in antioxidant activity increased largely in retina and lenses at a daily verbascoside dose of 3 mg, whereas for optic nerve and vitreous humor the higher antioxidant capacity was measured at 4 mg/die verbascoside dose. The present findings demonstrate that verbascoside supplementation is able to protect ocular tissue and fluids from naturally occurring oxidation and that its protective effect depends on the daily dose, being maximum up to 3 mg/die.


Asunto(s)
Antioxidantes/farmacología , Suplementos Dietéticos , Ojo/efectos de los fármacos , Glucósidos/farmacología , Lippia/química , Estrés Oxidativo/efectos de los fármacos , Fenoles/farmacología , Extractos Vegetales/farmacología , Animales , Liebres , Cristalino/efectos de los fármacos , Masculino , Nervio Óptico/efectos de los fármacos , Oxidación-Reducción , Retina/efectos de los fármacos , Sustancias Reactivas al Ácido Tiobarbitúrico , Cuerpo Vítreo/efectos de los fármacos
10.
Cell Biochem Biophys ; 68(2): 267-74, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23797611

RESUMEN

This work aimed to consider the hazardous side effect of eye floaters treatment with Q-switched Nd:YAG laser on the protein and viscoelastic properties of the vitreous humor, and evaluate the protective role of vitamin C against laser photo disruption. Five groups of New Zealand rabbits were divided as follows: control group for (n = 3) without any treatment, the second group (n = 9) treated with Q-switched Nd:YAG laser energy of 5 mJ × 100 pulse delivered to the anterior, middle, and posterior vitreous, respectively (n = 3 for each). The third group (n = 9) received a daily dose of 25 mg/kg body weight vitamin C for 2 weeks, and then treated with laser as the previous group. The fourth group (n = 9) treated with 10 mJ 9 50 pulse delivered to the anterior, middle, and posterior vitreous, respectively (n = 3 rabbits each). The fifth group (n = 9) received a daily dose of 25 mg/kg body weight vitamin C for 2 weeks, and then treated with laser as the previous group. After 2 weeks of laser treatment, the protein content, refractive index (RI), and the rheological properties of vitreous humor, such as consistency, shear stress, and viscosity, were determined. The results showed that, the anterior vitreous group exposed to of 5 mJ × 100 pulse and/or supplemented with vitamin C, showed no obvious change. Furthermore, all other treated groups especially for mid-vitreous and posterior vitreous humor showed increase in the protein content, RI and the viscosity of vitreous humor. The flow index remained below unity indicating the non-Newtonian behavior of the vitreous humor. Application of Q-switched Nd:YAG laser should be restricted to the anterior vitreous humor to prevent the deleterious effect of laser on the gel state of the vitreous humor.


Asunto(s)
Láseres de Estado Sólido , Reología , Cuerpo Vítreo/efectos de la radiación , Animales , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Masculino , Conejos , Refractometría , Viscosidad , Cuerpo Vítreo/efectos de los fármacos , Cuerpo Vítreo/fisiología
11.
J Ocul Pharmacol Ther ; 29(2): 258-69, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23331052

RESUMEN

PURPOSE: Dexamethasone palmitate (DXP) is a lipophilic prodrug of dexamethasone (DXM), a potent corticosteroid used to treat a variety of ophthalmic diseases. The aim of the study was to characterize the sustained release capacity (in rabbit), efficacy (in rat and rabbit), and safety (in rabbit, cat, and minipig) of intravitreal (IVT) DXP emulsions in preclinical models. METHODS: Oil-in-water emulsions of DXP were administered by IVT injections in rats, rabbits, cats, or minipigs. Efficacy was assessed in rabbits by the inhibition of VEGF-induced vascular leakage and in rats by inhibition of laser-induced choroidal neovascularization. Concentrations of DXP and DXM in aqueous humor, vitreous, retina, choroid, and blood were determined to characterize the ocular and systemic pharmacokinetic (PK) profile. Complete ophthalmic examinations (indirect ophthalmoscopy, slit-lamp biomacroscopy, electroretinography, tonometry) were performed to assess the ocular safety of IVT DXP doses up to 2,600 µg in minipig, followed by histopathologic examinations. A validated feline model of DXM-induced elevated intraocular pressure (IOP) was used to assess the ocular hypertensive impact (i.e., the safety) of an IVT injection of DXP emulsion. RESULTS: Rat and rabbit efficacy data demonstrated that IVT injections of DXP emulsions were effective. Rabbit PK data demonstrated that following a single 1,280 µg IVT injection resulted in sustained DXM levels in the retina and choroid (1,179.6 and 577.7 ng/g with a half-life of 189 and 103 days, respectively) sufficient to inhibit VEGF-induced vascular hyper-permeability for up to 9 months. No adverse ocular findings were observed in the rabbit at the 1,280 µg DXP dose. Plasma levels of DXP and DXM were close to the lower limit of quantification (0.5 ng/mL). In minipigs, no systemic effects were observed at a dose up to 2,600 µg DXP. In steroid responsive cats, IVT DXP emulsions increased IOP to a lesser extent than triamcinolone acetonide with a more rapid return to basal levels and no evidence of cataract formation. CONCLUSIONS: IVT injections of DXP emulsions were well tolerated and shown to be efficacious for the sustained release of the drug, with the potential to control vascular leakage up to 9 months following a single IVT injection. These data suggest that IVT injections of DXP emulsions could be a safe and effective alternative IVT drug delivery vehicle for corticosteroid to treat back of the eye diseases complicated by macular edema.


Asunto(s)
Corticoesteroides/administración & dosificación , Dexametasona/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Edema Macular/tratamiento farmacológico , Ácido Palmítico/administración & dosificación , Cuerpo Vítreo/efectos de los fármacos , Corticoesteroides/metabolismo , Animales , Gatos , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/metabolismo , Dexametasona/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Emulsiones , Femenino , Edema Macular/metabolismo , Masculino , Ácido Palmítico/metabolismo , Conejos , Distribución Aleatoria , Ratas , Ratas Endogámicas BN , Porcinos , Porcinos Enanos , Resultado del Tratamiento , Cuerpo Vítreo/metabolismo
12.
Retina ; 32 Suppl 2: S225-8; discussion S228-31, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22929326

RESUMEN

The vitreous may play an important role in the pathogenesis of various retinal disorders. Pharmacologic vitreolysis uses intravitreal pharmacologic agents to provide liquefaction of the vitreous and complete vitreoretinal separation. Ocriplasmin, a genetically engineered version of plasmin, has been shown in clinical trials to be able to safely release vitreomacular adhesion and close Stage 2 macular holes in a significant number of patients. Advancements in the development of this safe and effective method of vitreolysis have provided an alternative, nonsurgical treatment option to physicians who manage these patients. A roundtable of clinical investigators convened to discuss and summarize recent progress in pharmacologic vitreolysis. Preclinical studies, and efficacy and safety data from controlled clinical trials of ocriplasmin were presented and discussed. Case studies were then presented to provide an opportunity for experts to reveal their specific thoughts regarding ocriplasmin for the treatment of vitreomacular adhesion and resulting vitreomacular traction and macular holes, based on their own interpretation of current clinical data and experience.


Asunto(s)
Fibrinolisina/farmacología , Fragmentos de Péptidos/farmacología , Cuerpo Vítreo/efectos de los fármacos , Ensayos Clínicos como Asunto , Evaluación Preclínica de Medicamentos , Fibrinolisina/efectos adversos , Adhesiones Focales/efectos de los fármacos , Humanos , Fragmentos de Péptidos/efectos adversos , Retina/metabolismo , Enfermedades de la Retina/prevención & control , Cuerpo Vítreo/metabolismo , Desprendimiento del Vítreo/etiología
13.
Arch Ophthalmol ; 130(7): 908-13, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22776928

RESUMEN

OBJECTIVE: To assess the safety and efficacy of combined cataract extraction, posterior chamber intraocular lens placement, pars plana vitrectomy, fluocinolone acetonide intravitreal implant (Retisert), and Ahmed valves with pars plana tube (CPR-PT) in eyes with chronic, posterior, noninfectious uveitis. METHODS: Retrospective study of patients who underwent CPR-PT. Outcome measures included visual acuity, intraocular pressure, inflammation, and complications. RESULTS: Eight eyes were included, with a mean follow-up of 18 months. Mean visual acuity improved from 1.89 to 0.14 logMAR (Snellen, counting fingers at 2 ft [0.6 m]) to 20/30; P=.01). Mean intraocular pressure remained stable at 16 to 17 mm Hg (P=.35). The number of glaucoma medications per eye decreased from 2.9 to 0.25 (P=.01). Systemic prednisone therapy was discontinued in all patients by 9 months postoperatively. Inflammation was well controlled in all eyes. CONCLUSION: The CPR-PT procedure allows rapid visual rehabilitation without major short-term complications.


Asunto(s)
Extracción de Catarata , Implantes de Medicamentos , Fluocinolona Acetonida/administración & dosificación , Implantes de Drenaje de Glaucoma , Implantación de Lentes Intraoculares , Uveítis Posterior/complicaciones , Vitrectomía , Adulto , Anestesia Local , Antihipertensivos/administración & dosificación , Catarata/complicaciones , Catarata/terapia , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Glaucoma/complicaciones , Glaucoma/cirugía , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Segmento Posterior del Ojo , Complicaciones Posoperatorias , Estudios Retrospectivos , Esclerostomía , Técnicas de Sutura , Resultado del Tratamiento , Uveítis Posterior/tratamiento farmacológico , Agudeza Visual/fisiología , Cuerpo Vítreo/efectos de los fármacos
14.
Acta Ophthalmol ; 90(5): e344-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22676067

RESUMEN

PURPOSE: To evaluate the safety profile of a brimonidine extended release intravitreal implant, in normotensive rabbit eyes. METHODS: Devices were made from hollow poly-l-lactic acid (PLA) tubes and contained hundred micrograms of brimonidine pamoate. Device was injected intravitreally in one eye of 12 New Zealand pigmented rabbits, whereas other eye was injected with a sham implant in masked fashion. Ocular examination was conducted at baseline and months 1, 3 and 6 including dilated fundus examination and electro-retinogram (ERG). Four rabbits were sacrificed at each time-point for retinal histology. ERG data were compared between groups and time-points using anova. RESULTS: No complications were reported from either eye of any rabbits over a 6-month period. Photopic A wave was reduced in the control eye at 1 month compared with baseline (p < 0.01). There was no significant difference in other ERG parameters between the groups at different time-points. Gross retinal histology was normal at all time-points. CONCLUSION: Extended release intravitreal brimonidine device was found to be safe and in normotensive rabbit eyes.


Asunto(s)
Antihipertensivos/toxicidad , Portadores de Fármacos , Quinoxalinas/toxicidad , Cuerpo Vítreo/efectos de los fármacos , Animales , Antihipertensivos/administración & dosificación , Tartrato de Brimonidina , Adaptación a la Oscuridad/fisiología , Evaluación Preclínica de Medicamentos , Implantes de Medicamentos , Electrorretinografía , Masculino , Poliésteres , Quinoxalinas/administración & dosificación , Conejos , Retina/efectos de los fármacos , Retina/fisiología
15.
Curr Eye Res ; 37(10): 871-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22632164

RESUMEN

PURPOSE: This study was designed to measure vitamin D metabolites in the aqueous and vitreous humor and in tear fluid, and to determine if dietary vitamin D3 supplementation affects these levels. We also determined if the corneal epithelium can synthesize vitamin D following UV-B exposure. METHODS: Rabbits were fed a control or vitamin D3 supplemented diet. Pilocarpine-stimulated tear fluid was collected and aqueous and vitreous humor were drawn from enucleated eyes. Plasma vitamin D was also measured. To test for epithelial vitamin D synthesis, a human corneal limbal epithelial cell line was irradiated with two doses of UV-B (10 and 20 mJ/cm(2)/day for 3 days) and vitamin D was measured in control or 7-dehydrocholesterol treated culture medium. Measurements were made using mass spectroscopy. RESULTS: 25(OH)-vitamin D3 and 24,25(OH)(2)-vitamin D3 increased significantly following D3 supplementation in all samples except vitreous humor. Tear fluid and aqueous humor had small but detectable 1,25(OH)(2)-vitamin D3 levels. Vitamin D2 metabolites were observed in all samples. Vitamin D3 levels were below the detection limit for all samples. Minimal vitamin D3 metabolites were observed in control and UV-B-irradiated epithelial culture medium except following 7-dehydrocholesterol treatment, which resulted in a UV-B-dose dependent increase in vitamin D3, 25(OH)-vitamin D3 and 24,25(OH)(2)-vitamin D3. CONCLUSIONS: There are measurable concentrations of vitamin D metabolites in tear fluid and aqueous and vitreous humor, and oral vitamin D supplementation affects vitamin D metabolite concentrations in the anterior segment of the eye. In addition, the UV exposure results lead us to conclude that corneal epithelial cells are likely capable of synthesizing vitamin D3 metabolites in the presence of 7-dehydrocholesterol following UV-B exposure.


Asunto(s)
24,25-Dihidroxivitamina D 3/farmacocinética , Calcifediol/farmacocinética , Rayos Ultravioleta , 24,25-Dihidroxivitamina D 3/metabolismo , Animales , Humor Acuoso/efectos de los fármacos , Humor Acuoso/metabolismo , Humor Acuoso/efectos de la radiación , Calcifediol/metabolismo , Línea Celular , Epitelio Corneal/citología , Epitelio Corneal/metabolismo , Epitelio Corneal/efectos de la radiación , Humanos , Limbo de la Córnea/citología , Limbo de la Córnea/metabolismo , Limbo de la Córnea/efectos de la radiación , Mióticos/farmacología , Pilocarpina/farmacología , Conejos , Lágrimas/efectos de los fármacos , Lágrimas/metabolismo , Cuerpo Vítreo/efectos de los fármacos , Cuerpo Vítreo/metabolismo , Cuerpo Vítreo/efectos de la radiación
17.
Am J Ophthalmol ; 151(2): 333-7.e2, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21168822

RESUMEN

PURPOSE: To compare the anesthetic effectiveness of 3 topical agents used for intravitreal injections. DESIGN: Randomized, triple-armed, double-blinded, prospective, single-centered trial in patients receiving intravitreal ranibizumab for neovascular age-related macular degeneration. METHODS: Patients were randomized 1:1:1 to receive 0.5% tetracaine hydrochloride drops and a 4% lidocaine pledget (n = 31), 0.5% tetracaine hydrochloride drops alone (n = 31), or 4% cocaine (+ epinephrine 1/100,000) drops alone (n = 31). Patients were asked to score their pain experience using a visual analogue scale (VAS) immediately following and 15 minutes after their injection. The average of these scores was used as the primary outcome. The physician performing the procedure separately scored his perception of the patients' pain using the Wong-Baker FACES scale. RESULTS: Means of the averaged VAS pain score for Groups 1, 2, and 3 were: 19 (95% confidence interval [CI] 12-26), 21 (95% CI 13-29), and 21 (95% CI 16-27) respectively. Mean Wong-Baker pain scores for Groups 1, 2, and 3 were 1.9 (95% CI 1.3-2.6), 2.1 (95% CI 1.4-2.7), and 2.3 (95% CI 1.6-3.1) respectively. There was no significant difference (P = .549) between groups for average VAS pain score. Similarly, there was no significant difference (P = .790) for the physician-perceived pain score between groups. CONCLUSIONS: There was no clinical difference in patient pain experience between the 3 anesthetic options tested. The addition of a 4% lidocaine pledget offered no clinical advantage in pain relief compared to 0.5% tetracaine or 4% cocaine (+ epinephrine 1/100,000) drops alone.


Asunto(s)
Analgesia/métodos , Anestesia Local/métodos , Anestésicos Locales/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Degeneración Macular/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Anestésicos Combinados/administración & dosificación , Anticuerpos Monoclonales Humanizados , Cocaína/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Inyecciones Intravítreas , Lidocaína/administración & dosificación , Masculino , Dimensión del Dolor , Estudios Prospectivos , Ranibizumab , Tetracaína/administración & dosificación , Cuerpo Vítreo/efectos de los fármacos
18.
Ophthalmologe ; 108(3): 237-43, 2011 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-21170652

RESUMEN

BACKGROUND: Intravitreal ranibizumab (Lucentis®) is an effective treatment for exudative age-related macular degeneration (AMD). Up to now, settlement for this therapy remains quite complex and is handled differently by insurance companies as well as in the different German states. Often applications must be submitted and approved before an injection can be made. This procedure is time consuming and a delay in starting treatment might result. The aim of this study was to determine the effect of late-onset injection on visual acuity before and during the upload procedure. METHODS: All patients treated with ranibizumab intravitreally between February 2007 and May 2010 were retrospectively evaluated for their best-corrected visual acuity at the day of diagnosis, injections during the upload phase and first follow-up visit after upload. RESULTS: A total of 1,149 eyes were evaluated and divided into 2 groups according to time between diagnosis and first injection (group 1: ≤10 days, group 2: >10 days). There was no statistically significant difference between the groups for average age, gender, visual acuity at day of diagnosis and type of choroidal neovascularisation. However, both groups differed in the loss of visual acuity before the first injection and the possible increase in visual acuity. Group 1 waiting ≤10 days showed - in contrast to group 2 waiting >10 days--a smaller loss of visual acuity before upload and greater gain of visual acuity during upload. Those differences were statistically significant. CONCLUSION: Successful treatment of exudative AMD requires small intervals between diagnosis and first ranibizumab injection. After diagnosis, the first injection with ranibizumab should be given as early as possible.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Seguro de Servicios Farmacéuticos/economía , Degeneración Macular/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Anciano , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/economía , Anticuerpos Monoclonales Humanizados , Esquema de Medicación , Costos de los Medicamentos/estadística & datos numéricos , Diagnóstico Precoz , Femenino , Estudios de Seguimiento , Alemania , Hospitales Universitarios , Humanos , Cobertura del Seguro/economía , Inyecciones Intravítreas , Degeneración Macular/diagnóstico , Degeneración Macular/economía , Masculino , Programas Nacionales de Salud/economía , Pronóstico , Ranibizumab , Estudios Retrospectivos , Agudeza Visual/efectos de los fármacos , Cuerpo Vítreo/efectos de los fármacos , Listas de Espera
19.
Retina ; 31(3): 535-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21102369

RESUMEN

PURPOSE: To compare the effectiveness of four different anesthetic methods for intravitreal injection. METHODS: Twenty-four patients each received four intravitreal injections using each of four types of anesthesia (proparacaine, tetracaine, lidocaine pledget, and subconjunctival injection of lidocaine) in a prospective, masked, randomized block design. Pain was graded by the patient on a 0 to 10 scale for both the anesthesia and the injection. RESULTS: The average combined pain scores for both the anesthesia and the intravitreal injection were 4.4 for the lidocaine pledget, 3.5 for topical proparacaine, 3.8 for the subconjunctival lidocaine injection, and 4.1 for topical tetracaine. The differences were not significant (P = 0.65). There were also no statistical differences in the individual anesthesia or injection pain scores. Subconjunctival lidocaine injection had the most side effects. CONCLUSION: Topical anesthesia is an effective method for limiting pain associated with intravitreal injections.


Asunto(s)
Anestesia Local/métodos , Anestésicos Locales/administración & dosificación , Inhibidores de la Angiogénesis/administración & dosificación , Dolor Ocular/diagnóstico , Degeneración Macular/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Bevacizumab , Método Doble Ciego , Femenino , Humanos , Inyecciones Intravítreas , Lidocaína/administración & dosificación , Masculino , Dimensión del Dolor , Propoxicaína/administración & dosificación , Estudios Prospectivos , Ranibizumab , Tetracaína/administración & dosificación , Cuerpo Vítreo/efectos de los fármacos
20.
Can J Microbiol ; 56(1): 1-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20130687

RESUMEN

The goal of this study was to compare in vitro and in vivo efficacy of moxifloxacin and liposomal amphotericin B (Amp-B) monotherapies and combination treatment against Candida albicans in an exogenous endophthalmitis model in rabbit eyes. Microplate dilution tests and checkerboard analysis were performed to detect in vitro efficacies. Endophthalmitis was induced by intravitreal injection of C. albicans in 40 rabbit eyes with simultaneous intravitreal drug injection according to prophylactic treatment groups. Group 1 (control group) received 0.1 mL of balanced salt solution, group 2 (moxi group) 100 microg moxifloxacin/0.1 mL, group 3 (Amp-B group) 10 microg liposomal Amp-B/0.1 mL, and group 4 (combi group) both 100 microg moxifloxacin/0.1 mL [DOSAGE ERROR CORRECTED] and 10 microg liposomal Amp-B/0.05 mL intravitreally. Clinical examination, quantitative analysis of microorganisms, and histopathologic examination were performed as in vivo studies. The minimum inhibitory concentration of liposomal Amp-B against C. albicans was found to be 1 microg/mL. Moxifloxacin showed no inhibition of in vitro C. albicans growth. The minimum inhibitory concentration values of liposomal Amp-B for C. albicans were reduced two- to eightfold with increasing concentrations of moxifloxacin in vitro. In vivo, there was no C. albicans growth in the combi group (zero of eight eyes), whereas three eyes (37.5%) showed growth in the Amp-B group. Vitreous inflammation, retinal detachment, focal retinal necrosis, and outer nuclear layer loss were found to be lower in the moxi group compared with the control group. Ganglion cell and inner nuclear layer loss was observed in all eyes (100%) in both the moxi and combi groups, whereas only in 25% (two of eight eyes) in the Amp-B group. Moxifloxacin strongly augments the efficacy of liposomal Amp-B against C. albicans in vitro, although it has no in vitro antifungal activity when used alone. It is interesting that we found a synergistic effect for in vitro tests but failed to demonstrate it in vivo. When 100 microg moxifloxacin/0.1 mL is given intravitreally, it has some toxic effects that are limited to the inner retinal layers.


Asunto(s)
Anfotericina B , Antifúngicos , Compuestos Aza , Candida albicans , Candidiasis , Endoftalmitis , Infecciones Fúngicas del Ojo , Quinolinas , Anfotericina B/farmacología , Anfotericina B/uso terapéutico , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Compuestos Aza/farmacología , Compuestos Aza/uso terapéutico , Candida albicans/efectos de los fármacos , Candida albicans/fisiología , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología , Candidiasis/patología , Recuento de Colonia Microbiana , Modelos Animales de Enfermedad , Farmacorresistencia Fúngica/efectos de los fármacos , Quimioterapia Combinada , Endoftalmitis/tratamiento farmacológico , Endoftalmitis/microbiología , Endoftalmitis/patología , Oftalmopatías/tratamiento farmacológico , Oftalmopatías/patología , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Infecciones Bacterianas del Ojo/patología , Infecciones Fúngicas del Ojo/tratamiento farmacológico , Infecciones Fúngicas del Ojo/microbiología , Infecciones Fúngicas del Ojo/patología , Fluoroquinolonas , Pruebas de Sensibilidad Microbiana , Moxifloxacino , Quinolinas/farmacología , Quinolinas/uso terapéutico , Conejos , Cuerpo Vítreo/efectos de los fármacos , Cuerpo Vítreo/microbiología , Cuerpo Vítreo/patología
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