RESUMEN
Water content in the cornea may affect the outcome of its excimer laser ablation, especially in presbyopic patients with myopic refraction. This hypothesis can be tested by scanning the cornea in the terahertz (THz) range to determine its hydration level. PURPOSE: To study the effect of hydration of the cornea determined by non-contact THz scanning and its biomechanical parameters on the results of photorefractive keratectomy (PRK) in an experiment. MATERIAL AND METHODS: PRK was performed using the Nidek EC-5000 QUEST excimer laser on 8 rabbit eyes. Corneal hydration was evaluated by determining the reflection coefficient (RC) in the THz electromagnetic radiation range before PRK, after 3-5 days, and after 1, 2, 3, and 4 months. Clinical examination included autorefractometry, assessment of corneal thickness and other anatomical and optical parameters of the anterior eye segment (Galilei G6, Ziemer Ophthalmic Systems AG 6.0.2, Switzerland), measurement of corneal hysteresis (CH) and corneal resistance factor (CRF) using the Ocular Response Analyzer (ORA; Reichert, USA), as well as tear production (Schirmer test). RESULTS: The initial water content in the cornea has a significant effect on the thickness of the removed layer, i.e. on the PRK effect, with correlation coefficient of Rs= -0.976 (p<0.01). The correlation between CH and the ablation depth is less pronounced (Rs=0.643), and CRF had no correlation with it (Rs= -0.089). Biomechanical indicators of the cornea depend on its hydration: changes in CH and CRF after excimer laser ablation qualitatively coincide with changes in RC, the correlation coefficient between RC and the initial value of CH is R= -0.619 (moderate negative correlation). CONCLUSION: THz scanning is an effective non-contact technology for monitoring corneal hydration level. The mismatch of the hypoeffect of keratorefractive excimer laser intervention planned for patients with presbyopia with the actual outcome can be caused by individual decrease in the initial water content in the cornea.
Asunto(s)
Miopía , Queratectomía Fotorrefractiva , Animales , Segmento Anterior del Ojo , Córnea/diagnóstico por imagen , Córnea/cirugía , Humanos , Láseres de Excímeros , Miopía/diagnóstico , Miopía/cirugía , ConejosRESUMEN
PURPOSE: To assess the effect of latanoprost and fixed combination of dorzolamide/timolol on ocular hemodynamics in patients with primary open-angle glaucoma (POAG). MATERIAL AND METHODS: The study examined 34 patients (56 eyes) aged 51 to 69 years (average - 62.4±9.7 years) diagnosed with POAG in the initial (31 eyes) or advanced stage (25 eyes). Patients of the first group (20 patients, 36 eyes) were receiving latanoprost (Glauprost, Rompharm Company, Romania). The second group (14 patients, 20 eyes) was assigned to receive a fixed combination of dorzolamide/timolol (Dorzopt plus, Rompharm Company, Romania). Patient examination before and at 6 and 12 months included tonometry (ICare PRO), perimetry (Heidelberg Edge Perimeter), HRT and OCT of the optic nerve (Heidelberg Retina Tomograph 3 and Spectralis OCT2), as well as measurement of the density of surface (SVL) and deep (DVL) vascular plexus, and the Bruch's membrane opening minimum rim width (BMO-MRW). Additionally, we evaluated microcirculation in the choroid (MC) according to our original technique that uses Spectralis OCT2, and calculated rheographic index (RI) and stroke volume using transpalpebral rheoophthalmography. RESULTS: The decrease in IOP in the Latanoprost group was on average 27% and in the control group receiving timolol and dorzolamide - on average 22% and remained stable until the end of the study. The value of the area and volume of the disc rim band, BMO-MRW did not exhibit statistically significant changes in both groups by the 12th month of observation. A tendency to increase the RI from 51.5±24.5 to 62.2±19 (p=0.084) and the median of the index of microcirculation of the choroid (MC) from 16476 up to 23767 (p=0.062) in 1st group was observed. CONCLUSION: The study confirms the feasibility of using latanoprost and a fixed combination of dorzolamide and timolol in ocular hypotensive therapy of glaucoma thanks to their pronounced hypotensive effect. Patients were noted to have a tendency for improvement of ocular hemodynamics when using latanoprost.
Asunto(s)
Glaucoma de Ángulo Abierto , Anciano , Antihipertensivos , Inhibidores de Anhidrasa Carbónica/uso terapéutico , Combinación de Medicamentos , Glaucoma de Ángulo Abierto/tratamiento farmacológico , Hemodinámica , Humanos , Presión Intraocular , Persona de Mediana Edad , Prostaglandinas Sintéticas/uso terapéuticoRESUMEN
PURPOSE: To study the hypotensive efficacy and safety of Travapress (0.004% travoprost) in patients with primary open-angle glaucoma (POAG). MATERIAL AND METHODS: The study included 50 patients (91 eyes) aged 45 to 74 years. The first group consisted of 23 patients (41 eyes) who received monotherapy with Travaprost. Patients of the second group (27 patients, 50 eyes) Travaprost was added to therapy with timolol 0.5% (17 patients, 32 eyes) or dorzolamide 2% (10 patients, 18 eyes). Travaprost was given for a period of 6 months. IOP was determined in 2 weeks, 1, 3 and 6 months from the beginning of treatment and daily IOP measurement was at 10.00, 12.00, 14.00 and 16.00. Subjective symptoms were evaluated in points by special scales. RESULTS: The study was completed by 42 patients (84%, 79 eyes). Two patients (4.7%) has stopped to use Travapress due to the side effects. Local side effects were observed in 9 patients (21.4%) with mild hyperemia being the most common and seen in 5 patients (11.9%). In the first group, the maximum IOP decrease was recorded for 3 months of the study and amounted to 7.3±1.2 mm Hg (27.5%) compared to baseline. By 6 months, IOP decreased by 6.8±1.5 mm Hg on average (25.6%). In the second group in the subgroup with timolol 0,5% IOP decreased by 4,9±1.7 mm Hg (20%) compared to baseline, in the subgroup with dorzolamid 2% - by 4,3±1,3 mm Hg (16,9%) compared to baseline. Evening use the drug was accompanied by significantly lower levels of daily IOP fluctuations compared with morning intake (3.0±1.2 and 3.8±1.7 mm Hg, respectively, p = 0,002). CONCLUSION: Travapress was established as highly efficient and safe. It can be recommended for wide use in the treatment of patients with POAG.
Asunto(s)
Antihipertensivos , Glaucoma de Ángulo Abierto , Hipertensión Ocular , Travoprost , Anciano , Antihipertensivos/efectos adversos , Antihipertensivos/uso terapéutico , Cloprostenol , Método Doble Ciego , Glaucoma de Ángulo Abierto/tratamiento farmacológico , Humanos , Presión Intraocular , Persona de Mediana Edad , Timolol , Travoprost/efectos adversos , Travoprost/uso terapéutico , Resultado del TratamientoRESUMEN
The ultraviolet (UV) B-induced damage of the eye surface of experimental animals (rabbits) includes loss of corneal epithelium, apoptosis of keratocytes and stromal edema. These changes are accompanied by clinically and histologically manifested corneal inflammation, neutrophil infiltration, and exudation of the anterior chamber of the eye. According to mass spectrometric analysis, UV-induced corneal damage is associated with pronounced changes in the lipid composition of tears, including a decrease in the amount of arachidonic acid and prostaglandin E2 and an increase in the concentrations of prostaglandin D2 and its derivative 15d-PGJ2. In addition, it is accompanied by an alteration in the levels of hydroxyeicosate tetraenic acid derivatives, namely upregulation of 12-HETE and downregulation of 5-HETE. The revealed changes indicate the activation of metabolic pathways involving 5-lipoxygenase, 12-lipoxygenase, cyclooxygenase 1 and 2, and prostaglandin-D-synthase. These findings contribute to understanding mechanisms of UV-induced keratitis and point on feasibility of selective anti-inflammatory therapy for improving corneal regeneration after iatrogenic UV damage.
Asunto(s)
Ácido Araquidónico/metabolismo , Lesiones de la Cornea/metabolismo , Queratitis/metabolismo , Lágrimas/química , Animales , Córnea , Conejos , Traumatismos por Radiación/metabolismo , Rayos Ultravioleta/efectos adversosRESUMEN
PURPOSE: To study the connective tissue (CT) structure of upper eyelid skin of primary open-angle glaucoma (POAG) patients. PATIENTS AND METHODS: Forty-seven patients aged 47-91 expecting blepharoplasty formed 3 groups: group 1 [16 subjects without POAG, median age 55 years (interquartile range 54-55.5)], group 2 [12 subjects without POAG, median age 73 (72-76.5)], and group 3 [(19 subjects with POAG, median age 74 (70-80.5)]. Age differences between groups 1 and 2 and groups 1 and 3 are significant (p < 0.05). Thermodynamic parameters of skin samples taken during blepharoplasty: Endothermic peak ([Formula: see text], °C) and denaturation enthalpy ([Formula: see text], J/g of dry weight) were determined using differential scanning calorimetry. RESULTS: [Formula: see text] and [Formula: see text] in groups 1-3 were, respectively, 8.41 (7.42-10.25) and 66.55 (59.9-66.7); 7.10 (5.76-10.17) and 67.35 (67.0-68.03); 11.40 (9.0-14.9) and 67.70 (67.05-68.45). [Formula: see text] differences between groups 1 and 2 are significant (p < 0.05), and Spearman's correlation between the age and [Formula: see text] is direct, medium (R = 0.638) and significant. [Formula: see text] in group 3 is significantly higher than in group 2. [Formula: see text] and [Formula: see text] in patients without POAG (groups 1 and 2) and those with POAG (group 3) are, respectively, 7.79 (6.9-10.17) and 66.6 (61.2-67,3); 11.40 (9.0-14.9); 67.7 (67.05-68.45); the respective differences are significant. CONCLUSION: Patients without POAG show a significant increase in [Formula: see text] with age, while [Formula: see text] slightly decreases. In POAG, [Formula: see text] is significantly higher and [Formula: see text] tends to grow, which may indicate structural changes in eyelid CT (collagen accumulation and cross-linking level rise). Since the upper lid is unaffected by increasing IOP directly, the changes may be viewed as manifestations of systemic CT pathology.
Asunto(s)
Tejido Conectivo/patología , Párpados/patología , Glaucoma de Ángulo Abierto/diagnóstico , Tomografía de Coherencia Óptica/métodos , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Colorimetría , Tejido Conectivo/fisiopatología , Párpados/fisiopatología , Femenino , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Termodinámica , Campos Visuales/fisiologíaRESUMEN
PURPOSE: To determine optimal design parameters of a transpalpebral tonometry sensor (the weight and diameter of the rod) based on experimental simulation. MATERIAL AND METHODS: The study has been conducted in situ at the forensic analysis department with 12 eyes of 5 men and one woman aged 49 to 71 years. Comparison between the tonometric pressure and the true pressure measured with direct manometric technique ensured the accuracy of transpalpebral tonometry data and helped select optimal sensor parameters. For this purpose, an experimental assembly was designed and produced, comprised of a testing stand with a system of tubes filled with distilled water, an indicating pressure gauge calibrated by the height of the water column, a millimeter scale on a holder, as well as a needle with connecting tubes and two valves. RESULTS: No statistically significant differences between the tonometric and manometric level of pressure in the eye were observed when using a sensor weighing 16 g with rod diameter of 1.5 or 3 mm. Only an insignificant dependence of the tonometry data on the thickness of the eyelid was noted at high levels of intraocular pressure (IOP). CONCLUSION: The experimental study conducted on the developed assembly has allowed us to substantiate the choice of optimal design parameter for a transpalpebral IOP measurement sensor. A transpalpebral tonometer with such sensor characteristics can be recommended for comparative clinical study, as well as for determination of its effectiveness in dynamical monitoring of the IOP levels.
Asunto(s)
Presión Intraocular , Tonometría Ocular , Anciano , Párpados , Femenino , Humanos , Masculino , Manometría , Persona de Mediana Edad , Reproducibilidad de los ResultadosRESUMEN
Visual system is at high risk of iatrogenic damage. Laser ocular surgery, the use of powerful illumination devices in diagnostics and surgical treatment of eye diseases, as well as long surgeries under general anesthesia provoke the development of chronic degenerative changes in eye tissues, primarily in the cornea and the retina. Despite the existence of approaches for prevention and treatment of these complications, the efficacy of these approaches is often limited. Here, we review the mechanisms of iatrogenic damage to eye tissues at the cellular and biochemical levels. It is well recognized that oxidative stress is one of the main factors hindering regeneration of eye tissues after injuries and, thereby, aggravating iatrogenic eye disorders. It is accompanied by the downregulation of low-molecular-weight antioxidants and antioxidant enzymes, as well as changes in the expression and redox status of proteins in the damaged tissue. In this regard, antioxidant therapy, in particular, the use of highly effective mitochondria-targeted antioxidants such as SkQ1, is considered as a promising approach to the prevention of iatrogenesis. Recent findings indicate that the most efficient protection of eye tissues from the iatrogenic injury is achieved by preventive use of these antioxidants. In addition to preventing corneal and retinal cell death induced by oxidative stress, SkQ1 contributes to the restoration of innate antioxidant defense of these tissues and suppresses local inflammatory response. Since the timing of routine medical manipulations is usually known in advance, iatrogenic damage to the ocular tissues can be successfully prevented using mitochondria-targeted therapy.
Asunto(s)
Oftalmopatías , Enfermedad Iatrogénica , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Oftalmopatías/tratamiento farmacológico , Oftalmopatías/etiología , Oftalmopatías/patología , Oftalmopatías/prevención & control , Humanos , Enfermedad Iatrogénica/prevención & control , Mitocondrias/efectos de los fármacosRESUMEN
AIM: to study peripheral refraction and the shape of the eyeball in children with different clinical refraction. MATERIAL AND METHODS: Using an original method, peripheral refraction was measured at 10-12 degrees temporally and nasally from the fovea in 56 right eyes with different clinical, or axial, refraction of 20 boys and 36 girls aged 7 to 16 years (11.9±1.17 years on average). The shape of the eyeball was judged of by the ratio of its anterior-posterior axial length (AL) to horizontal diameter (HD). RESULTS: The incidence and value of peripheral myopic defocus in children appeared to decrease with clinical refraction increasing from high hyperopia to high myopia. This was the first time, mixed peripheral refraction was found in children, occurring more frequently in higher myopia. This mixed peripheral defocus, shown to be a transitional stage between relative peripheral myopia and relative hyperopia, indicates non-uniform stretching of posterior pole tissues in the course of refraction development and myopia progression. As ocular refraction increases from high hyperopia to high myopia, the growth of AL outpaces that of HD. CONCLUSION: Obviously, natural peripheral defocus results from changes in size and shape of the eyeball in the course of refraction development.
Asunto(s)
Longitud Axial del Ojo/crecimiento & desarrollo , Miopía , Refracción Ocular/fisiología , Errores de Refracción , Adolescente , Niño , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Miopía/diagnóstico , Miopía/etiología , Miopía/fisiopatología , Errores de Refracción/complicaciones , Errores de Refracción/diagnóstico , Errores de Refracción/fisiopatologíaRESUMEN
BACKGROUND: Quantitative assessment of hemodynamic parameters is an important element of ophthalmic diagnostics especially in early detection of myopia, glaucoma, diabetic retinopathy. The assessment of hemodynamic changes is essential in evaluating of the efficiency of treatment. Objective: Our aim was to determine the adequate of eye hemodynamics assessment using reoophtalmography in patients with various clinical refractions. METHODS: A controlled study was carried out. All tests were performed using transpalpebral tetrapolar method. Signal registration lasted for 20 seconds in the supine position, and then the diagnostic parameters were calculated. RESULTS: We present the results of examination of 76 patients aged 5 to 22 years (average age 13.0 ± 1.1). 32 patients had low myopia (62 reoophtalmography records), 23 patients had moderate myopia (42 records) and 5 patients had high myopia (12 records). The control group was composed of 16 patients. The main differences were found in the rheographic index, which is equal to 58.1 ± 4.1 mOhm in the control group. It is significantly reducing with refraction increase, from 47.8 ± 3.2 mOhm in low myopia to 34.0 ± 2.5 mOhm in high myopia (p = 0.050). This is an evidence of blood supply deficiency in the myopic eyes. CONCLUSION: Rheographic index was shown to differ in different breathing phases, which agrees with the known physiological regularities. The proposed method is highly informative and sufficiently accurate what allows assessing the eye blood supply state objectively. It is easy to apply and requires no contact with the eye surface, which is especially important in pediatric practice.
Asunto(s)
Ojo/irrigación sanguínea , Miopía , Pletismografía de Impedancia/métodos , Adolescente , Técnicas de Diagnóstico Oftalmológico , Femenino , Humanos , Masculino , Miopía/diagnóstico , Miopía/fisiopatología , Pediatría/métodos , Flujo Sanguíneo Regional , Reproducibilidad de los ResultadosRESUMEN
The growing prevalence of progressive myopia and its disabling consequences explains the elaboration of reliable diagnostic markers and new treatment strategies based on the research results of molecular mechanisms underlying the development of the condition. The paper reviews recent basic pathogenetic research studies which have greatly broadened the awareness of the deep causes of progressive myopia associated with the activity of certain growth factors, local and systemic protein metabolism, and regulation of hormonal and neural processes. Practical clinical guidelines for new criteria of diagnosis and control of myopia are published as they could be useful while selecting individual treatment plans including indications to sclera-strengthening therapy and its evaluation. The results may be promising in the elaboration of systemic and local medications for the prevention of myopia progression, which should address the regulation of connective tissue disorders, hormonal shifts, and imbalanced autonomic nervous system.
Asunto(s)
Proteínas del Ojo/metabolismo , Miopía , Epitelio Pigmentado Ocular/metabolismo , Animales , Ensayos Clínicos como Asunto , Manejo de la Enfermedad , Progresión de la Enfermedad , Humanos , Modelos Animales , Miopía/diagnóstico , Miopía/etiología , Miopía/metabolismo , Miopía/fisiopatología , Miopía/terapia , Guías de Práctica Clínica como AsuntoRESUMEN
The purpose of the study was to develop a new algorithm of aqueous humor dynamics assessment in glaucomatous eyes, which would take into account the shape of the tonographic curve and individual elastic properties of the corneoscleral capsule. Basic ophthalmic examination supplemented with tonography and differentiated tonometry was performed on 33 patients with primary open-angle glaucoma (POAG), 8 POAG suspects, and 9 healthy controls. Obtained data were processed in accordance with the developed algorithm. A new formula for calculating the coefficient of outflow facility and several additional parameters describing the condition of aqueous pathways were proposed. In POAG patients these parameters significantly differed from those in healthy controls.
Asunto(s)
Humor Acuoso/fisiología , Glaucoma de Ángulo Abierto , Presión Intraocular/fisiología , Anciano , Algoritmos , Femenino , Glaucoma de Ángulo Abierto/diagnóstico , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Hidrodinámica , Masculino , Persona de Mediana Edad , Modelos Teóricos , Tonometría Ocular/métodosRESUMEN
The correlation between biomechanical properties of the corneoscleral tunic and stereometric parameters of the optic nerve head in children and adolescents with congenital and acquired myopia has been studied comparatively. The results showed that in children with high myopia, congenital or acquired, the corneoscleral parameters (scleral echodensity at the equator and the posterior pole, corneoscleral hysteresis, cornea resistance factor, and ocular rigidity coefficient) are lower than those in emmetropes. Moreover, the corneoscleral biomechanical characteristics affect the optic nerve head parameters. This fact has to be taken into account when examining adults with high myopia for the purpose of early diagnostics of glaucoma.
Asunto(s)
Córnea/fisiopatología , Miopía/fisiopatología , Disco Óptico/fisiopatología , Esclerótica/fisiopatología , Adolescente , Niño , Elasticidad , Humanos , Presión Intraocular , Miopía/congénito , PronósticoRESUMEN
We have shown previously the presence of full length (50 kD) and truncated proteolytic form (45 kD) of pigment epithelium derived factor (PEDF) in the eye Tenon's capsule in progressive myopia. The full length PEDF is prevalent in myopia that correlates with breach in collagen fibrils forming. Immunohistochemical analysis of Tenon's capsule with polyclonal antibodies to PEDF revealed PEDF in control group being exclusively inside fibroblasts, whereas in myopia, PEDF was distributed extracellularly as halo around blasted fibroblasts. By means of atomic force microscopy and immunodot analysis with anti amyloid fibrils antibodies the ability was studied of recombinant PEDF fragments to form fibrils. Only full length PEDF was shown to form amyloid like fibril structures, but not the truncated form. Accumulation offibrils results in fibroblasts destruction and might be the cause of changes in biochemical and morphological structure of Tenon's capsule observed in myopia.
Asunto(s)
Amiloide , Proteínas del Ojo , Miopía Degenerativa , Factores de Crecimiento Nervioso , Serpinas , Cápsula de Tenon , Amiloide/metabolismo , Amiloide/ultraestructura , Matriz Extracelular/metabolismo , Ojo/metabolismo , Ojo/patología , Proteínas del Ojo/metabolismo , Proteínas del Ojo/ultraestructura , Fibroblastos/metabolismo , Microscopía de Fuerza Atómica , Miopía Degenerativa/metabolismo , Miopía Degenerativa/patología , Factores de Crecimiento Nervioso/metabolismo , Factores de Crecimiento Nervioso/ultraestructura , Proteolisis , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serpinas/metabolismo , Serpinas/ultraestructura , Cápsula de Tenon/metabolismo , Cápsula de Tenon/patología , Cápsula de Tenon/ultraestructuraRESUMEN
The goal of the investigation was to study the changes of scleral matrix collagen in progressing primary open-angle glaucoma (POAG). In scleral samples of 16 patients aged 52-81 years with different stages of POAG amino acid composition, collagen content and cross-linking ratio characterizing tissue rigidity were estimated. Collagen I was found to be the dominant type in sclera of glaucomatous and normal eyes, though as POAG progressing the content and cross-linking increase, that underlies the scleral rigidity increase and permeability decrease. Similar ratio of collagen cross-linking with age and glaucoma progression give evidence of specific pathologic changes of the dominant matrix component, that may be one of significant pathogenic factor of POAG.
Asunto(s)
Colágeno/metabolismo , Glaucoma de Ángulo Abierto/metabolismo , Glaucoma de Ángulo Abierto/patología , Esclerótica/metabolismo , Anciano , Anciano de 80 o más Años , Aminoácidos/análisis , Aminoácidos/metabolismo , Colágeno/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerótica/química , Esclerótica/patologíaRESUMEN
To study the possibility of corneal contribution to process of accommodation in myopic eyes we examined 4 groups of patients: children and adolescents with low (1st group) to moderate (2nd group) myopia, young adults with moderate to high myopia after LASIK (3rd group) and PRK (4th group). Corneal optic power was measured using binocular open-field autoreferatometer in vertical and horizontal meridians for near (33 sm) and distant (5 m) fixation. No significant difference was found in children and adolescents with low and moderate myopia with intact cornea, as well as in young adults with moderate to high myopia after keratorefractive surgery. The optic corneal power tends to be moderately lower in horizontal meridian, but this difference is not significant. The revealed data do not support significant contribution of cornea into accommodation of the myopic eye.
Asunto(s)
Acomodación Ocular/fisiología , Córnea/patología , Miopía/patología , Adolescente , Adulto , Niño , Córnea/fisiopatología , Topografía de la Córnea , Humanos , Miopía/fisiopatología , Refracción Ocular , Agudeza Visual , Adulto JovenRESUMEN
The paper aims at the evaluation of prospects for using glyceraldehyde as a cross-linking agent for the scleral tissue. Stability parameters (denaturation temperature, Young's modulus, ultimate tensile stress, proteolytic resistance) and analytical parameter (fluorescence intensity) were determined during the glycation process of isolated rabbit sclera. The analysis of fluorescence spectral characteristic provided information about some glycation products. The glyceraldehyde treatment was resulted in a significant increase in thermal stability, proteolytic resistance and improvement of biomechanical characteristics (Young's modulus, ultimate tensile stress). Unique properties of the reaction between scleral collagen and glyceraldehyde are observed at short cross-linking times. The appearance of intermediate collagen fraction with lowest thermal and proteolytic stability was detected.
Asunto(s)
Colágeno/química , Reactivos de Enlaces Cruzados/química , Gliceraldehído/química , Esclerótica/química , Animales , Rastreo Diferencial de Calorimetría , Color , Elasticidad , Endopeptidasas/química , Glicosilación , Complejos Multienzimáticos/química , Papaína/química , Desnaturalización Proteica , Conejos , Espectrometría de Fluorescencia , Resistencia a la Tracción , Temperatura de TransiciónRESUMEN
Mitochondria-targeted cationic plastoquinone derivative SkQ1 (10-(6'-plastoquinonyl) decyltriphenylphosphonium) has been investigated as a potential tool for treating a number of ROS-related ocular diseases. In OXYS rats suffering from a ROS-induced progeria, very small amounts of SkQ1 (50 nmol/kg per day) added to food were found to prevent development of age-induced cataract and retinopathies of the eye, lipid peroxidation and protein carbonylation in skeletal muscles, as well as a decrease in bone mineralization. Instillation of drops of 250 nM SkQ1 reversed cataract and retinopathies in 3-12-month-old (but not in 24-month-old) OXYS rats. In rabbits, experimental uveitis and glaucoma were induced by immunization with arrestin and injections of hydroxypropyl methyl cellulose to the eye anterior sector, respectively. Uveitis was found to be prevented or reversed by instillation of 250 nM SkQ1 drops (four drops per day). Development of glaucoma was retarded by drops of 5 microM SkQ1 (one drop daily). SkQ1 was tested in veterinarian practice. A totally of 271 animals (dogs, cats, and horses) suffering from retinopathies, uveitis, conjunctivitis, and cornea diseases were treated with drops of 250 nM SkQ1. In 242 cases, positive therapeutic effect was obvious. Among animals suffering from retinopathies, 89 were blind. In 67 cases, vision returned after SkQ1 treatment. In ex vivo studies of cultivated posterior retina sector, it was found that 20 nM SkQ1 strongly decreased macrophagal transformation of the retinal pigmented epithelial cells, an effect which might explain some of the above SkQ1 activities. It is concluded that low concentrations of SkQ1 are promising in treating retinopathies, cataract, uveitis, glaucoma, and some other ocular diseases.
Asunto(s)
Envejecimiento , Oftalmopatías/veterinaria , Mitocondrias/metabolismo , Plastoquinona/análogos & derivados , Animales , Transporte Biológico , Ceguera/tratamiento farmacológico , Ceguera/fisiopatología , Ceguera/veterinaria , Gatos , Perros , Oftalmopatías/tratamiento farmacológico , Oftalmopatías/fisiopatología , Oftalmopatías/prevención & control , Femenino , Caballos , Técnicas In Vitro , Masculino , Mitocondrias/química , Mitocondrias/efectos de los fármacos , Plastoquinona/metabolismo , Plastoquinona/farmacología , Progeria/inducido químicamente , Progeria/fisiopatología , Progeria/veterinaria , Conejos , Ratas , Especies Reactivas de Oxígeno/metabolismo , Retina/efectos de los fármacos , Retina/metabolismo , Retina/fisiopatologíaRESUMEN
It has been shown by biochemical analysis and differential scanning calorimetry that the connective tissue formed around a transplant as a result of sclero-reinforcing interference (capsula) is similar to intact sclera. The main component of newly formed capsules is collagen I whose fibers have a perfect structure and the amount of cross-links sufficient to provide normal thermomechanical properties. A fraction of collagen having thermally labile "immature" cross-links in capsules formed around the transplant impregraned with Panaxal has been detected by differential scanning calorimetry. It was suggested that fibroblasts in tissues of these capsules have a high synthetic activity.
Asunto(s)
Tejido Conectivo/química , Éteres/química , Prótesis e Implantes , Esclerótica/química , Esclerótica/cirugía , Animales , Rastreo Diferencial de Calorimetría , Colágeno Tipo I/análisis , Fibroblastos/química , Calor , Conejos , TemperaturaRESUMEN
The paper presents the results of experimental use of a polyglycolide material-based filling for temporary episcleral filling in retinal detachment. Thorough comparative morphological and biomechanical studies of 120 experimental eyes in different periods after scleroplasty, by using an inflatable balloon catheter, homoscleral and polyglycolide fillings, have indicated that the polyglycolide filling material is completely lysed by ocular tissues within 60-90 days, which rules out a repeated surgical intervention for removal of temporary filling (for example, an inflatable balloon catheter), by preserving the constancy of the depth of scleral pressing-in. The short existence of a chemically indifferent polyglycolide filling in the ocular tissues excludes its negative effect on the surrounding structures of the eye, minimizes the likelihood of the occurrence of early postoperative complications, but thereby leading to a substantial increase in the biochemical stability of the scleral-and-chorioretinal complex in the early postoperative periods and ensuring increased resistance to dynamic loads, by forming a stable scleral-and-chorioretinal adhesion 3 months after surgery. The findings suggest that the designed polyglycolide explant has advantages and that it is expedient to introduce the new Russian resolving polyglycolide fiber explants into clinical practice (for scleroplastic operations).
Asunto(s)
Implantes Absorbibles , Ácido Poliglicólico , Desprendimiento de Retina/cirugía , Curvatura de la Esclerótica/instrumentación , Animales , Modelos Animales de Enfermedad , Estudios de Seguimiento , Complicaciones Posoperatorias/prevención & control , Conejos , Reproducibilidad de los Resultados , Desprendimiento de Retina/patología , Resultado del Tratamiento , Cicatrización de HeridasRESUMEN
The purpose of the case study was to evaluate the remote consequences of a complex of laser and repeated surgical sclerorestorative procedures made in progressing myopia and its complications. Three hundred and forty-six children, aged 8-10, with rapidly progressing uncomplicated myopia of 4.25 to 9.5 D were shared between 2 groups. Two hundred and forty patients of the experimental group were made sclerorestorative procedures and transscleral low-energy laser stimulation of the ciliary muscle by means of infrared laser MACDEL-09. No such treatment was applied to patients of the control group. When indicated, preventive laser coagulation of the retina was made in both groups. The dynamic 10-year follow-up over the status of refraction and eye bottom showed that the complex scheme of repeated sclerorestorative procedures and low-energy laser treatment combined with preventive peripheral laser coagulation of the retina cut the rate of progressing myopia and prevented peripheral vitreoretinal dystrophy and retinal detachment in children and teenagers with progressing myopia.