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1.
Surg Laparosc Endosc Percutan Tech ; 26(5): 368-371, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27579982

RESUMEN

Gastroduodenal stents are effective for gastric outlet obstruction (GOO) due to gastric cancer. However, some patients are unable to eat again soon. We retrospectively analyzed the cause of short-feeding periods. Between 2011 and 2015, we performed stent placement in 22 patients who could not eat solids. The effects of clinical characteristics on duration of oral intake were analyzed using Cox proportional hazards models. Univariate analyses revealed that the degree of GOO [no oral intake/liquids only; hazard ratio (HR), 10.9; 95% confidence interval (CI), 2.5-48.1; P=0.003], performance status score (2 or 3/0 or 1; HR, 5.7; 95% CI, 1.8-16.9; P=0.004), and poststenting chemotherapy (no/yes; HR, 5.7; 95% CI, 1.9-18.9; P=0.002) were significant factors for cessation of oral intake. Multivariate analysis showed that GOO and chemotherapy were significant factors. Gastroduodenal stents were less effective for patients with severe stenosis or without poststenting chemotherapy.


Asunto(s)
Ingestión de Alimentos , Gastroscopía/métodos , Estenosis Pilórica/cirugía , Stents , Neoplasias Gástricas/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Estimación de Kaplan-Meier , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estenosis Pilórica/complicaciones , Estudios Retrospectivos , Neoplasias Gástricas/complicaciones , Resultado del Tratamiento
2.
Radiat Prot Dosimetry ; 155(3): 284-91, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23390146

RESUMEN

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.


Asunto(s)
Calor , Cristalino/efectos de la radiación , Ondas de Radio/efectos adversos , Temperatura Cutánea/efectos de la radiación , Adulto , Animales , Catarata/etiología , Simulación por Computador , Relación Dosis-Respuesta en la Radiación , Humanos , Masculino , Microondas , Modelos Biológicos , Conejos
3.
J Cataract Refract Surg ; 38(10): 1783-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22929087

RESUMEN

PURPOSE: To compare and evaluate changes in the retinal image with age in Japanese adults with transparent crystalline lenses. SETTING: Shibuya-ku, Tokyo, Japan. DESIGN: Cross-sectional study. METHODS: The study comprised right eyes with corrected distance visual acuity better than 0.0 logMAR. A point-spread function analyzer (PSF-1000) was used to measure retinal image contrast with 3.0 mm pupils under maximum mydriasis. A wavefront analyzer (KR9000PW) was used to measure higher-order aberrations (HOAs) with 4.0 mm pupils. The lens transparency property was estimated by the backward light-scattering intensity of each layer of the lens and the optical distance (mm) photographed by an anterior segment analysis system (EAS-1000). The Pearson product-moment correlation (R(2)) was used for statistical analysis; the significance level was 5%. RESULTS: The study comprised 269 patients (mean age 39.7 years ± 7.7 [SD]). The retinal image contrast degenerated significantly with age; the largest difference was seen with the 0.423 logMAR optotype, for which the decrease was 5.4% every decade. Backward light-scattering intensity (R(2) = 0.030, P<.01) and HOAs (R(2) = 0.032, P<.01) correlated negatively with retinal image contrast. CONCLUSION: Retinal image contrast in eyes with transparent lenses degenerated with age. The decrease was most prominent at the middle frequency domain and was due to the increase in HOAs and light-scattering intensity.


Asunto(s)
Envejecimiento/fisiología , Sensibilidad de Contraste/fisiología , Cristalino/fisiología , Retina/fisiología , Aberrometría , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fotograbar , Agudeza Visual/fisiología , Adulto Joven
4.
Eye Contact Lens ; 37(4): 191-5, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21670696

RESUMEN

PURPOSE: To assess the validity of the solar ultraviolet index (UVI) as a determiner of eye risk under different conditions of facial profiles and orientation, and reflected light. METHODS: Ocular UV radiation (UVR) exposure was measured as a function of the time of the day (solar altitude) using a two-dummy-type mannequin dosimetry system with embedded UVR (260-310 nm) sensors, in September and November in Kanazawa, Japan, on a motorized sun-tracking mount with one dummy face directed toward the sun and the other away from the sun. RESULTS: A bimodal distribution of UV-B exposure was found in September for the face directed toward the sun, which differed dramatically from the pattern of ambient UVR exposure and measurements taken on the top of the head and those for the eye taken later in the year. Although the overall level was lower, a higher solar altitude is associated with higher UVR exposure in the condition facing away from the sun. CONCLUSIONS: The UVI is based on ambient solar radiation on an unobstructed horizontal plane similar to our measures taken on the top of the head, which differed so much from our measures of ocular exposure that UVI as a determiner of eye risk is deemed invalid. The use of the UVI as an indicator for the need for eye protection can be seriously misleading. Doctors should caution patients with regard to this problem, and eye protection may be warranted throughout the year.


Asunto(s)
Altitud , Ojo/efectos de la radiación , Luz Solar , Rayos Ultravioleta , Humanos , Maniquíes , Reproducibilidad de los Resultados
5.
Ophthalmic Res ; 46(1): 38-43, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21212707

RESUMEN

PURPOSE: To describe the pattern of expression of the cyclin-dependent kinase inhibitors (CDKIs) p16, p21 and p27, and the cell cycle in SRA 01/04 cells relative to contact inhibition. METHODS: SRA 01/04 cells were grown to overconfluence under normal conditions. At various phases of the cell growth, cells were assayed by flow cytometry and Western blotting for the expression of CDKIs. RESULTS: Expression of p16 was detected from early logarithmic growth to stationary phases, during which the number of cells in G(0)/G(1) increased from 46 to 69%. Expression of p21 was detected only during the overgrowth phase, when 60% of the cells were in G(0)/G(1). Expression of p27 was not observed in SRA 01/04 cells. CONCLUSIONS: p16 expression was likely mediated by G(0)/G(1) arrest to induce contact inhibition in SRA 01/04. p21 expression may be related to withdrawal, and p27 deficiency may be related to the immortality of this cell line. It is possible for p16 to stop proliferation of lens epithelial cells like progressing posterior capsular opacification, by overexpression to mimic contact inhibition.


Asunto(s)
Ciclo Celular/fisiología , Inhibición de Contacto/fisiología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Células Epiteliales/metabolismo , Cristalino/metabolismo , Western Blotting , Recuento de Células , Línea Celular , Proliferación Celular , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Citometría de Flujo , Humanos
6.
J Cataract Refract Surg ; 36(5): 799-805, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20457372

RESUMEN

PURPOSE: To compare visual acuity and ocular higher-order aberrations (HOAs) in eyes with waterclefts, a type of crystalline lens opacity, and in normal eyes. SETTING: Department of Ophthalmology, Kanazawa Medical University, Ishikawa, Japan, and Faculty of Medicine, University of Iceland, Reykjavik, Iceland. METHODS: In this nested case-control study of subjects attending the third examination of the Reykjavik Eye Study in 2008, eyes with pure waterclefts and control eyes with no lenticular opacity were evaluated. All candidates had complete ophthalmic examinations and wavefront analysis. Higher-order aberrations in the watercleft group and the control group were compared. RESULTS: The watercleft group comprised 30 eyes and the control group, 194 eyes. The mean corrected distance visual acuity (CDVA) in the watercleft group was statistically significantly lower than in the control group (P<.01). There was a significant relationship between CDVA and HOA in both groups. Total HOA and trefoil and coma aberrations were statistically significantly higher in the watercleft group than in the control group (P<.05). CONCLUSIONS: Waterclefts significantly affected CDVA. Eyes with waterclefts had higher coma and trefoil aberrations, suggesting that the increased HOAs caused reduced visual acuity in eyes with waterclefts.


Asunto(s)
Catarata/complicaciones , Aberración de Frente de Onda Corneal/etiología , Agudeza Visual/fisiología , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Catarata/clasificación , Catarata/epidemiología , Aberración de Frente de Onda Corneal/fisiopatología , Femenino , Humanos , Islandia/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos
7.
Jpn J Ophthalmol ; 53(5): 531-5, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19847611

RESUMEN

PURPOSE: 5-S-Glutathionyl-N-beta-alanyl-3,4-dihydroxyphenylalanine (5-S-GAD) is a novel antibacterial substance purified from Sarcophaga peregrina (flesh fly) that has both a radical scavenging activity and antioxidative activity. This is a report of an investigation of the effect of 5-S-GAD (eyedrops) on UVB-induced cataracts in rats. METHODS: Brown Norway male rats (n = 32; 7 weeks old) were treated with either 5-S-GAD 0.1%, 5-SGAD 1%, astaxanthin (AST) 0.1% suspension eyedrops or the vehicle alone (the solution without 5-S-GAD) three times a day (three doses at 5-min intervals each time). The treatment was scheduled 2 days before UV-B exposure and 2 days after UV-B exposure. Exposure to 100-200 mJ/cm(2) UV-B was performed once a week between drug treatments for 9 consecutive weeks, with a total dose of 1200 mJ/cm(2) UV-B. Ocular penetration of 5-S-GAD was analyzed using high-pressure liquid chromatography (HPLC). Cataract formation was documented by an anterior eye segment analysis system once a week under mydriasis. The light-scattering intensity (LSI) of the anterior superficial cortex region was measured. RESULTS: In the eighth to ninth week after the start of UV-B exposure, the LSI of anterior subcapsular lenses of 5-S-GAD-treated groups, as detected by HPLC, was significantly lower (P < 0.05) than that of the control, whereas no such difference was found in the AST-treated group. CONCLUSION: 5-S-GAD eyedrop application may delay the progression of UV-B-induced cataract in rats.


Asunto(s)
Antioxidantes/administración & dosificación , Catarata/tratamiento farmacológico , Dihidroxifenilalanina/análogos & derivados , Depuradores de Radicales Libres/administración & dosificación , Glutatión/análogos & derivados , Cristalino/efectos de la radiación , Traumatismos Experimentales por Radiación/tratamiento farmacológico , Rayos Ultravioleta/efectos adversos , Administración Tópica , Animales , Antioxidantes/farmacocinética , Catarata/etiología , Catarata/fisiopatología , Cromatografía Líquida de Alta Presión , Dihidroxifenilalanina/administración & dosificación , Dihidroxifenilalanina/farmacocinética , Modelos Animales de Enfermedad , Depuradores de Radicales Libres/farmacocinética , Glutatión/administración & dosificación , Glutatión/farmacocinética , Cristalino/fisiopatología , Luz , Masculino , Soluciones Oftálmicas , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Traumatismos Experimentales por Radiación/etiología , Ratas , Ratas Endogámicas BN , Dispersión de Radiación
8.
Health Phys ; 97(3): 212-8, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19667804

RESUMEN

The goal of this study was to examine the clinical course of 60-GHz millimeter-wave induced damages to the rabbit eye and to report experimental conditions that allow reproducible induction of these injuries. The eyes of pigmented rabbits (total number was 40) were irradiated with 60-GHz millimeter-waves using either a horn antenna or one of two lens antennas (6 and 9 mm diameter; phi6, phi9) Morphological changes were assessed by slit-lamp microscopy. Additional assessments included corneal fluorescein staining, iris fluorescein angiography, and lens epithelium light microscopy. Under the standardized eye-antenna positioning, the three antennas caused varying damages to the eyelids or eyeglobes. The most reproducible injuries without concurrent eyelid edema and corneal desiccation were achieved using the phi6 lens antenna: irradiation for 6 min led to an elevation of the corneal surface temperature (reaching 54.2 +/- 0.9 degrees C) plus corneal edema and epithelial cell loss. Furthermore, mitotic cells appeared in the pupillary area of the lens epithelium. Anterior uveitis also occurred resulting in acute miosis (from 6.6 +/- 1.4 to 2.2 +/- 1.4 mm), an increase in flares (from 6.7 +/- 0.9 to 334.3 +/- 130.8 photons per second), and iris vasodilation or vessel leakage. These findings indicate that the three types of millimeter-wave antennas can cause thermal injuries of varying types and levels. The thermal effects induced by millimeter-waves can apparently penetrate below the surface of the eye.


Asunto(s)
Campos Electromagnéticos/efectos adversos , Lesiones Oculares/etiología , Traumatismos Experimentales por Radiación/etiología , Enfermedad Aguda , Animales , Quemaduras/etiología , Quemaduras/patología , Opacidad de la Córnea/etiología , Opacidad de la Córnea/patología , Modelos Animales de Enfermedad , Lesiones Oculares/patología , Iris/irrigación sanguínea , Iris/lesiones , Masculino , Miosis/etiología , Miosis/patología , Conejos , Dosis de Radiación , Traumatismos Experimentales por Radiación/patología , Reproducibilidad de los Resultados , Vasodilatación/efectos de la radiación
9.
Phys Med Biol ; 53(12): 3391-404, 2008 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-18523344

RESUMEN

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.


Asunto(s)
Temperatura Corporal/efectos de la radiación , Simulación por Computador , Campos Electromagnéticos , Calor , Modelos Biológicos , Dosis de Radiación , Irradiación Corporal Total , Absorción , Animales , Ojo/efectos de la radiación , Conejos , Radiometría , Recto/fisiología , Reproducibilidad de los Resultados , Factores de Tiempo
10.
Health Phys ; 94(2): 134-44, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18188048

RESUMEN

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.


Asunto(s)
Ojo/efectos de la radiación , Microondas , Fantasmas de Imagen , Animales , Relación Dosis-Respuesta en la Radiación , Exposición a Riesgos Ambientales , Conejos , Temperatura
11.
Acta Ophthalmol Scand ; 85(4): 361-6, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17286626

RESUMEN

PURPOSE: To study the correlation between ocular refraction and the refractive components (corneal power, lens power and axial length) in a population-based sample of normal subjects. METHODS: We analysed the refractive and biometric findings for 723 right eyes (325 males and 398 females) comprising a population-based random sample of citizens 55 years and older participating in the Reykjavik Eye Study. Measurements of refraction, corneal curvature (by keratometry), anterior chamber depth, lens thickness and axial length (all by ultrasound biometry) were used to calculate crystalline lens power. The correlation and regression between refraction and ocular refractive components (corneal power, anterior chamber depth, lens power and axial length) were studied by distributional statistical methods. RESULTS: Refraction (spherical equivalent) showed a significant negative correlation with axial length (r = -0.59, P < 0.0001), lens power (r = -0.26, P < 0.0001) and corneal power (r = -0.16, P < 0.0001). There were significant negative correlations between axial length and corneal power (r = -0.44, P < 0.0001) and between axial length and lens power (r = -0.44, P < 0.0001). Based on multiple linear regression analysis, refraction could be correlated with corneal power, lens power and axial length in combination with a correlation coefficient of 0.98 (P < 0.0001). CONCLUSION: This study confirms that ocular refraction is statistically significantly correlated with not only axial length but also lens power and (to a lesser extent) corneal power. The variation and correlations of crystalline lens power were considerable -- possibly indicating this component's modulatory effect on ocular refraction during growth. We conclude the refractive error of the eye to be a multifactorial condition involving a complex interplay between the cornea, the lens and the length of the eye.


Asunto(s)
Córnea/fisiología , Ojo/anatomía & histología , Cristalino/fisiología , Refracción Ocular/fisiología , Errores de Refracción/fisiopatología , Anciano , Biometría , Córnea/anatomía & histología , Femenino , Humanos , Islandia , Cristalino/anatomía & histología , Masculino , Persona de Mediana Edad
12.
Jpn J Ophthalmol ; 51(1): 10-3, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17295134

RESUMEN

PURPOSE: alpha-Lipoic acid (LA) is well known as a powerful antioxidant. The efficacy of dihydrolipoate-LA for oral administration against streptozotocin (STZ)-induced diabetic cataract in rat was investigated. METHODS: Rats were divided into three groups, control, diabetes mellitus (DM), and DM treated with LA (DM+LA). Diabetes was induced by intravenous injection of 50 mg/kg STZ. DM+LA rats were fed 30 mg/rat per day LA in their diet. Lens changes were assessed using Scheimpflug images (EAS-1000) and by measuring light-scattering intensity. RESULTS: Increase in lens light scattering was less (P < 0.05) in DM+LA rats than in DM rats 5 weeks after induction of diabetes. DM rats had the highest and control rats the lowest blood glucose levels at every measurement point up to 111 days (P < 0.05). CONCLUSION: LA treatment delayed development and progression of cataract in rats with streptozotocin-induced diabetes.


Asunto(s)
Antioxidantes/uso terapéutico , Catarata/tratamiento farmacológico , Diabetes Mellitus Experimental/tratamiento farmacológico , Ácido Tióctico/análogos & derivados , Ácido Tióctico/uso terapéutico , Administración Oral , Animales , Glucemia/análisis , Catarata/fisiopatología , Diabetes Mellitus Experimental/fisiopatología , Progresión de la Enfermedad , Quimioterapia Combinada , Femenino , Cristalino/fisiopatología , Luz , Ratas , Ratas Endogámicas BN , Dispersión de Radiación , Resultado del Tratamiento
13.
Am J Ophthalmol ; 142(3): 419-28, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16935586

RESUMEN

PURPOSE: To establish risk factors for five-year incidence of age-related macular degeneration (AMD). DESIGN: Population-based, prospective cohort study, and risk analysis. METHODS: A random sample from the Reykjavik Population Census for individuals 50 years and older was selected. We took fundus stereo color photographs and used standard grading system to study the five-year incidence of drusen, pigmentary abnormalities, and AMD and to examine possible risk factors. A questionnaire including information on disease, medication, diet, and lifestyle from the Reykjavik Eye Study database provided additional information. RESULTS: Current alcohol consumption decreased the risk for drusen. Being married rather than divorced or widowed decreased the risk for soft drusen; being single decreased the risk of hypopigmentation as compared with being divorced or married. Both consuming dietary fiber-rich vegetables and meat and meat products once a week or less frequently was a risk factor for developing soft drusen and decreased the risk of pigmentary abnormalities. Those who had smoked 20 pack-years or more as compared with nonsmokers had decreased survival rate over the five years (odds ratio (OR) 0.46, 95% confidence interval (CI) 0.27 to 0.80; P = .006). CONCLUSIONS: Risk factors for drusen appear to differ from risk factors for pigmentary abnormalities. The effect of smoking on developing AMD is partly masked by selective mortality.


Asunto(s)
Degeneración Macular/epidemiología , Anciano , Dieta , Registros de Dieta , Humanos , Islandia/epidemiología , Incidencia , Persona de Mediana Edad , Estudios Prospectivos , Drusas Retinianas/epidemiología , Factores de Riesgo , Fumar , Encuestas y Cuestionarios
14.
Bioelectromagnetics ; 27(8): 602-12, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16724330

RESUMEN

This paper computationally verifies the effect of anesthesia on temperature variations in the rabbit eye due to microwave energy. The main reason for this investigation is that our previous paper suggested a reduction in blood flow due to the administration of anesthesia, resulting in an overestimated temperature increase. However, no quantitative investigation has yet been conducted. The finite-difference time-domain (FDTD) method is used for calculating power absorption and temperature variation in rabbits. For this purpose, we used a computational rabbit phantom, which is comprised of 12 tissues (including 6 eye tissues) with a resolution of 1 mm. Thermal constants of the rabbit were derived by comparing measured and calculated temperatures. For intense microwave exposure to the rabbit eye, time courses of calculated and measured temperatures were in good agreement for cases both with and without the administration of anesthesia. The point to be stressed is that under anesthesia the thermoregulatory response was inactivated and blood flow and basal metabolism was reduced.


Asunto(s)
Anestésicos/farmacología , Regulación de la Temperatura Corporal/efectos de los fármacos , Ojo/efectos de los fármacos , Microondas/efectos adversos , Modelos Biológicos , Absorción/efectos de la radiación , Animales , Fenómenos Biofísicos , Biofisica , Ojo/irrigación sanguínea , Masculino , Conejos , Temperatura , Termómetros
15.
Ophthalmology ; 113(4): 565-9, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16581419

RESUMEN

PURPOSE: To establish the age- and gender-specific prevalence of cornea guttata (CG) in citizens of Reykjavik, Iceland, 55 years and older. DESIGN: Cross-sectional, random, population-based study. PARTICIPANTS: The 774 participants were those participating in the second examination of the Reykjavik Eye Study. At baseline, we had a response rate of 75.8%, and at the 5-year follow-up, 88% of the survivors participated. METHODS: We used slit-lamp and non-contact specular microscopy and endothelial specular photography as well as computer-assisted morphometry. We used a standardized grading system for CG. MAIN OUTCOME MEASURES: Diagnosis of primary central CG. RESULTS: The prevalence of CG is 11% for females and 7% for males both for right eyes and left eyes. Higher weight and higher body mass index are found to be associated with decreased risk of CG. Having smoked more than 20 pack-years increased the risk of CG more than 2-fold (P<0.02). CONCLUSIONS: Cornea guttata seem to be found more commonly in women than in men. Smoking for more than 20 pack-years increases the risk of developing CG more than 2-fold.


Asunto(s)
Enfermedades de la Córnea/epidemiología , Lámina Limitante Posterior/patología , Distribución por Edad , Anciano , Anciano de 80 o más Años , Recuento de Células , Enfermedades de la Córnea/diagnóstico , Estudios Transversales , Endotelio Corneal/patología , Femenino , Humanos , Islandia/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Distribución por Sexo
16.
Ophthalmology ; 112(1): 132-8, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15629833

RESUMEN

PURPOSE: To examine the age- and gender-specific 5-year incidence of age-related maculopathy (ARM) and age-related macular degeneration (AMD) in citizens of Reykjavik. DESIGN: Population-based, prospective cohort study. PARTICIPANTS: The cohort was a population-based random sample of citizens 50 years and older. Of 1379 eligible subjects, 1045 had a baseline examination in 1996; 846 of the 958 survivors (88.2%) had a 5-year follow-up examination in 2001. METHODS: The incidence of various characteristics of drusen and pigmentary changes that are typical of ARM were determined using the international classification and grading system for ARM and AMD. MAIN OUTCOME MEASURES: Early ARM and AMD were assessed by masked grading of stereo fundus photographs. RESULTS: Hypopigmentation developed at 5 years in 10.7% of people 50 to 59 years of age (95% confidence interval [CI], 6.9-14.4) and in 25.7% those 70 to 79 years of age (95% CI, 18.4-33.0) at baseline. Age-related macular degeneration developed in no one who was 50 to 59 years of age at baseline. Geographic atrophy (GA) developed in 4.6% (95% CI, 1.2-7.9) and exudative AMD in none of those who were 70 years and older at baseline. CONCLUSIONS: Geographic atrophy is the predominant type of AMD in Iceland, and the ratio of GA to neovascular AMD is higher than in racially similar populations.


Asunto(s)
Degeneración Macular/epidemiología , Distribución por Edad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Islandia/epidemiología , Incidencia , Degeneración Macular/clasificación , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Estudios Prospectivos , Distribución por Sexo
17.
Acta Ophthalmol Scand ; 83(6): 734-8, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16396653

RESUMEN

PURPOSE: To examine the relationships between adult stature, age and ocular dimensions in a large homogenous, white population. METHODS: We used the national population census for Reykjavik to select a random sample of adults aged 50 years or older. A total of 846 persons were examined. Scheimpflug images were used to measure anterior chamber depth. Ultrasound was used to measure axial length, lens thickness and vitreous chamber depth. An autorefracto-keratometer was used to measure autorefractive and keratometric values, including the radius of the corneal curvature. Stereo fundus photographs were taken of the optic disc and measurements of the disc diameters were made using computer software. RESULTS: Height correlated positively with axial length in the multivariate model (B = 0.020, 95% CI 0.006-0.034, p < 0.01). Both age and height showed significant correlations with vitreous chamber depth, where the correlation with age was negative (B = - 0.016, 95% CI - 0.006 to - 0.025, p < 0.005) and the correlation with height was positive (B = 0.019, 95% CI 0.005-0.034, p < 0.01). Height also showed a positive correlation with the radius of the corneal curvature (B = 0.008, 95% CI 0.004-0.011, p < 0.001). Anterior chamber depth had a negative correlation with age (B = - 0.013, 95% CI - 0.010 to - 0.016, p < 0.001), whereas lens thickness had a significant positive correlation with age (B = 0.019, 95% CI 0.016-0.023, p < 0.001). We found a significant negative correlation between axial length and refraction/spherical equivalent (r = - 0.595, p < 0.0001). DISCUSSION: Our results indicate that there is a significant relationship between height and several ocular dimensions in this adult population and confirms a negative correlation between axial length and refraction.


Asunto(s)
Envejecimiento/fisiología , Estatura/fisiología , Ojo/anatomía & histología , Anciano , Anciano de 80 o más Años , Ojo/diagnóstico por imagen , Femenino , Humanos , Islandia , Masculino , Persona de Mediana Edad , Ultrasonografía
18.
Ophthalmic Res ; 36(5): 277-83, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15583434

RESUMEN

To evaluate ocular morphological response to ultraviolet B (UV-B) exposure in guinea pigs fed with normal and low-ascorbic acid (ASA) diets, 24 guinea pigs were randomly divided into UVR (normal diet + UV-B), LVC (low-ASA diet + UV-B) and CTL (normal diet, without UV-B) groups. The irradiated animals were exposed to 8.2 J/cm(2) of UV-B over 29 weeks. Changes in the cornea and lens were examined using a Scheimpflug camera, specular microscope and histological studies. ASA contents in the plasma, aqueous humor and lens sections were measured by high-performance liquid chromatography. The results showed low contents of ASA in the plasma, aqueous humor and lens sections in LVC. Both irradiated groups displayed corneal epithelial edema, neovascularization in stroma, increase in corneal thickness, decrease in endothelial density, and lens epithelial damage. No significant morphological differences in cornea and lens were found between guinea pigs fed with low-ASA or normal diet.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Catarata/etiología , Córnea/efectos de la radiación , Edema Corneal/etiología , Neovascularización de la Córnea/etiología , Cristalino/efectos de la radiación , Traumatismos Experimentales por Radiación/etiología , Animales , Ácido Ascórbico/sangre , Catarata/metabolismo , Catarata/patología , Recuento de Células , Cromatografía Líquida de Alta Presión , Córnea/patología , Edema Corneal/metabolismo , Edema Corneal/patología , Neovascularización de la Córnea/metabolismo , Neovascularización de la Córnea/patología , Dieta , Femenino , Cobayas , Cristalino/metabolismo , Traumatismos Experimentales por Radiación/metabolismo , Traumatismos Experimentales por Radiación/patología , Rayos Ultravioleta , Cuerpo Vítreo/metabolismo
19.
Ophthalmic Res ; 36(4): 231-6, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15292662

RESUMEN

PURPOSE: To confirm whether long-term administration of prednisolone sodium succinate (prednisolone) alone is able to induce cataract in rat eyes. MATERIALS AND METHODS: A 1% solution of prednisolone was administered topically as eye drops to Brown Norway rat eyes, and a systemic pulse administration of 10 mg/kg/day was given via the tail vein. Both administration methods were applied in different combinations. Eighty-three 6-week-old male rats were divided into 8 groups: group 1 = control; group 2 = topical instillation every day; group 3 = single pulse; group 4 = single pulse + eye drops; group 5 = 3 times pulse; group 6 = 3 times pulse + eye drops; group 7 = 3 times pulse per 2 months; group 8 = 3 times pulse per 2 months + eye drops. Observations for changes of lens transparency were made by slitlamp microscopy and documented by an anterior eye segment analysis system (Nidek EAS-1000) from the onset of drug administration to a maximum period of 16 months. RESULTS: Lens opacity in the shallow anterior and posterior lens layers developed from the tenth month following commencement of prednisolone administration. The incidence of anterior and/or posterior cortical cataract at the sixteenth month was 15% in group 2, 12.5% in group 5, 25% in group 6, 17.9% in group 7 and 35.3% in group 8. The lenses of groups 1, 3 and 4 maintained their transparency throughout the observation period. Light scattering intensity in groups 8 and 7 was the highest, followed by groups 6 and 5, then groups 2, 4, 3 and 1. CONCLUSION: Cortical cataract was successfully induced in Brown Norway rat eyes by sustained administration of prednisolone succinate alone applied as systemic pulse.


Asunto(s)
Catarata/etiología , Glucocorticoides/toxicidad , Cristalino/efectos de los fármacos , Prednisolona/análogos & derivados , Prednisolona/toxicidad , Animales , Catarata/patología , Modelos Animales de Enfermedad , Glucocorticoides/administración & dosificación , Cristalino/patología , Masculino , Soluciones Oftálmicas/administración & dosificación , Prednisolona/administración & dosificación , Quimioterapia por Pulso , Ratas , Ratas Endogámicas BN
20.
Jpn J Ophthalmol ; 48(2): 93-6, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15060787

RESUMEN

PURPOSE: Pharmacokinetic studies of antibacterial agents for infectious eye diseases have usually been performed on normal rabbit eyes. In this study, the intraocular penetration of fluoroquinolone ophthalmic solutions was determined in normal rabbit eyes and in rabbit eyes that had the corneal epithelium intentionally removed. METHODS: We determined the intraocular penetration of ofloxacin (OFLX), levofloxacin (LVFX), and norfloxacin (NFLX), fluoroquinolone ophthalmic solutions that are already on the market and undergoing clinical studies, by injecting 50 microl of each solution into the cul-de-sacs of rabbit eyes three times at 15-min intervals. The drug concentration at 10, 30, 60, 120, and 240 min after final instillation was determined by high-performance liquid chromatography. RESULTS: The maximum concentration in the aqueous humor of normal rabbit eyes was 2.09 +/- 1.56 microg/ml (60 min, OFLX), 2.57 +/- 1.00 microg/ml (30 min, LVFX), and 0.42 +/- 0.12 microg/ml (120 min, NFLX). The drug concentration in the aqueous humor of eyes with intentionally removed corneal epithelium was 12.50 +/- 5.62 microg/ml (30 min, OFLX), 9.02 +/- 2.45 microg/ml (60 min, LVFX), and 8.54 +/- 5.17 microg/ml (30 min, NFLX). The drug penetration of the eye drops into eyes with removed corneal epithelium was around 6 times (OFLX), 3.5 times (LVFX), and 20 times (NFLX) higher than the penetration into the eye with normal cornea. CONCLUSION: Among the pharmacokinetic parameters of the three ophthalmic solutions according to the one-compartment model, the maximum concentration in the aqueous and the area under the concentration-time curve in the aqueous tended to be higher in the eyes with intentionally removed corneal epithelia than in those with normal corneas.


Asunto(s)
Antiinfecciosos/farmacocinética , Humor Acuoso/metabolismo , Córnea/metabolismo , Epitelio Corneal/fisiología , Fluoroquinolonas/farmacocinética , Animales , Área Bajo la Curva , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Levofloxacino , Masculino , Norfloxacino/farmacocinética , Ofloxacino/farmacocinética , Soluciones Oftálmicas/farmacocinética , Conejos
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