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1.
Graefes Arch Clin Exp Ophthalmol ; 262(9): 2751-2764, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38430228

RESUMEN

PURPOSE: This review explores mathematical models, blinking characterization, and non-invasive techniques to enhance understanding and refine clinical interventions for ocular conditions, particularly for contact lens wear. METHODS: The review evaluates mathematical models in tear film dynamics and their limitations, discusses contact lens wear models, and highlights computational mechanical models. It also explores computational techniques, customization of models based on individual blinking dynamics, and non-invasive diagnostic tools like high-speed cameras and advanced imaging technologies. RESULTS: Mathematical models provide insights into tear film dynamics but face challenges due to simplifications. Contact lens wear models reveal complex ocular physiology and design aspects, aiding in lens development. Computational mechanical models explore eye biomechanics, often integrating tear film dynamics into a Multiphysics framework. While different computational techniques have their advantages and disadvantages, non-invasive tools like OCT and thermal imaging play a crucial role in customizing these Multiphysics models, particularly for contact lens wearers. CONCLUSION: Recent advancements in mathematical modeling and non-invasive tools have revolutionized ocular health research, enabling personalized approaches. The review underscores the importance of interdisciplinary exploration in the Multiphysics approach involving tear film dynamics and biomechanics for contact lens wearers, promoting advancements in eye care and broader ocular health research.


Asunto(s)
Lentes de Contacto , Lágrimas , Humanos , Lágrimas/fisiología , Lágrimas/metabolismo , Ajuste de Prótesis , Parpadeo/fisiología , Síndromes de Ojo Seco/fisiopatología , Síndromes de Ojo Seco/metabolismo , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/terapia , Simulación por Computador , Modelos Teóricos , Fenómenos Biomecánicos
2.
Int J Mol Sci ; 24(21)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37958577

RESUMEN

Climate-change-induced temperature fluctuations pose a significant threat to crop production, particularly in the Southern Hemisphere. This study investigates the transcriptome and physiological responses of rapeseed to post-flowering temperature increases, providing valuable insights into the molecular mechanisms underlying rapeseed tolerance to heat stress. Two rapeseed genotypes, Lumen and Solar, were assessed under control and heat stress conditions in field experiments conducted in Valdivia, Chile. Results showed that seed yield and seed number were negatively affected by heat stress, with genotype-specific responses. Lumen exhibited an average of 9.3% seed yield reduction, whereas Solar showed a 28.7% reduction. RNA-seq analysis of siliques and seeds revealed tissue-specific responses to heat stress, with siliques being more sensitive to temperature stress. Hierarchical clustering analysis identified distinct gene clusters reflecting different aspects of heat stress adaptation in siliques, with a role for protein folding in maintaining silique development and seed quality under high-temperature conditions. In seeds, three distinct patterns of heat-responsive gene expression were observed, with genes involved in protein folding and response to heat showing genotype-specific expression. Gene coexpression network analysis revealed major modules for rapeseed yield and quality, as well as the trade-off between seed number and seed weight. Overall, this study contributes to understanding the molecular mechanisms underlying rapeseed tolerance to heat stress and can inform crop improvement strategies targeting yield optimization under changing environmental conditions.


Asunto(s)
Brassica napus , Brassica rapa , Brassica napus/genética , Transcriptoma , Temperatura , Brassica rapa/genética , Genotipo , Semillas/metabolismo
3.
Int J Mol Sci ; 22(9)2021 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-33923211

RESUMEN

A critical barrier to improving crop yield is the trade-off between seed weight (SW) and seed number (SN), which has been commonly reported in several crops, including Brassica napus. Despite the agronomic relevance of this issue, the molecular factors involved in the interaction between SW and SN are largely unknown in crops. In this work, we performed a detailed transcriptomic analysis of 48 seed samples obtained from two rapeseed spring genotypes subjected to different source-sink (S-S) ratios in order to examine the relationship between SW and SN under different field conditions. A multifactorial analysis of the RNA-seq data was used to identify a group of 1014 genes exclusively regulated by the S-S ratio. We found that a reduction in the S-S ratio during seed filling induces the expression of genes involved in sucrose transport, seed weight, and stress responses. Moreover, we identified five co-expression modules that are positively correlated with SW and negatively correlated with SN. Interestingly, one of these modules was significantly enriched in transcription factors (TFs). Furthermore, our network analysis predicted several NAC TFs as major hubs underlying SW and SN compensation. Taken together, our study provides novel insights into the molecular factors associated with the SW-SN relationship in rapeseed and identifies TFs as potential targets when improving crop yield.


Asunto(s)
Brassica napus/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo , Semillas/genética , Transcriptoma , Brassica napus/anatomía & histología , Brassica napus/crecimiento & desarrollo , Genotipo , Tamaño de los Órganos , Proteínas de Plantas/genética , Sitios de Carácter Cuantitativo , Semillas/anatomía & histología , Semillas/química , Semillas/crecimiento & desarrollo
4.
Eye Contact Lens ; 45(6): 377-381, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30946063

RESUMEN

OBJECTIVE: To assess the intrarater repeatability of the measurements of tear meniscus height (TMH), noninvasive keratograph tear break-up time (NIKBUTs), and ocular redness measurements obtained with the Keratograph 5M (K5M) in a sample of soft silicone hydrogel contact lens (CL) wearers over 15 days. METHODS: Prospective study over two consecutive weeks. Three measurements of TMH, NIKBUTs (NIKBUT first and NIKBUT average), and ocular redness were obtained in different sessions; the first day (baseline, at 8 hr of wear, and after lens removal) and the last day of wear-15th day (at 8 hr of wear and after lens removal). The repeatability of measurements were assessed by two intraclass correlation coefficient (ICC) forms; single measurement [ICC (2,1)] and multiple measurements (k=3) [ICC (2, k)]. RESULTS: Sixty-four eyes were analyzed. The repeatability of baseline TMH [ICC (2,1) greater than 0.90; coefficient of repeatability (CR)=0.06 mm] and after and during CL wear [ICC (2,k) greater than 0.90; CR≤0.07 mm] were excellent. The repeatability of baseline NIKBUT average [ICC (2,k)=0.89 (0.82-0.93); CR=6.07 sec] was maintained after CL removal but was poorer during CL wear. The repeatability of baseline NIKBUT first [ICC (2,k) =0.80 (0.69-0.87); CR=8.74 sec] was maintained after CL removal and during CL wear at moderate-good level. CONCLUSIONS: Intrarater repeatability of TMH, NIKBUTs, and ocular redness performed by K5M after CL wear remains stable when three measurements are performed. However, intrarater repeatability during CL wear decreased only for NIKBUT average and was not affected by time of use (15 days).


Asunto(s)
Lentes de Contacto Hidrofílicos , Córnea/fisiopatología , Topografía de la Córnea/instrumentación , Miopía/terapia , Lágrimas/fisiología , Adulto , Femenino , Humanos , Hiperemia/fisiopatología , Masculino , Miopía/fisiopatología , Estudios Prospectivos , Ajuste de Prótesis , Reproducibilidad de los Resultados , Lágrimas/química , Adulto Joven
5.
Eye Contact Lens ; 44(2): 77-84, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27243354

RESUMEN

OBJECTIVE: To assess the effects of a short period of orthokeratology (OK) on corneal sub-basal nerve plexus (SBNP) morphology and corneal sensitivity. METHODS: Measurements were made in 56 right eyes of 56 subjects with low-to-moderate myopia who wore 2 OK lens designs (Group CRT: HDS 100 Paragon CRT, n=35; Group SF: Seefree; n=21) for a period of 1 month and in 15 right eyes of noncontact lens wearers as controls. The variables determined in each participant were corneal sensitivity using a Cochet-Bonnet esthesiometer and 12 SBNP variables determined on laser scanning confocal microscopy images using 3 different software packages. Correlation between SBNP architecture and corneal sensitivity was also examined. RESULTS: Few changes were observed over the 1-month period in the variables examined in the OK treatment and control groups. However, significant reductions were detected over time in the number of nerves in the central cornea in the groups CRT (P=0.029) and SF (P=0.043) and in central corneal sensitivity in CRT (P=0.047) along with significant increases in central and midperipheral corneal Langerhans cell counts in SF (P=0.001 and 0.048, respectively). CONCLUSIONS: This study provides useful data to better understand the anatomical changes induced by OK in corneal SBNP. The different response observed to the 2 OK lens designs requires further investigation.


Asunto(s)
Córnea/inervación , Córnea/fisiología , Miopía/terapia , Red Nerviosa/anatomía & histología , Nervio Oftálmico/anatomía & histología , Procedimientos de Ortoqueratología , Adulto , Análisis de Varianza , Estudios de Casos y Controles , Sensibilidad de Contraste/fisiología , Femenino , Humanos , Masculino , Nervio Oftálmico/fisiología , Procedimientos de Ortoqueratología/efectos adversos , Procedimientos de Ortoqueratología/métodos , Estudios Prospectivos , Adulto Joven
6.
Eye Contact Lens ; 44(2): 91-96, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28410280

RESUMEN

PURPOSE: To examine the effects of one year of overnight orthokeratology (OK) treatment on the sub-basal nerve plexus (SBNP) and corneal sensitivity and to assess the reversibility of these effects one month after treatment interruption. METHODS: Thirty-two subjects with low-moderate myopia underwent OK treatment for one year. Fifteen non-contact lens wearers served as controls. At the time points baseline, one year of treatment, and one month after removing the OK lenses, two tests were conducted: corneal sensitivity (Cochet-Bonnet esthesiometer) and SBNP imaging by in vivo confocal microscopy. RESULTS: In participants wearing OK lenses, significant reductions over the year were produced in SBNP nerve density (P=0.001 and P=0.006) and number of nerves (P<0.001 and P=0.001) in the central and mid-peripheral cornea, respectively. Differences over the year were also detected in central objective tortuosity (P=0.002). After lens removal, baseline values of nerve density (P=0.024 and P=0.001) and number of nerves (P=0.021 and P<0.001) for the central and mid-peripheral cornea, respectively, were not recovered. At one month post-treatment, a difference was observed from one-year values in central corneal sensitivity (P=0.045) and mid-peripheral Langerhans cell density (P=0.033), and from baseline in mid-peripheral objective tortuosity (P=0.049). Direct correlation was detected at one year between nerve density and tortuosity both in the central (P<0.01; r=0.69) and mid-peripheral cornea (P<0.01; r=0.76). CONCLUSIONS: Long-term OK treatment led to reduced SBNP nerve density and this was directly correlated with corneal tortuosity. After one month of treatment interruption, nerve density was still reduced.


Asunto(s)
Lentes de Contacto , Córnea , Miopía/terapia , Red Nerviosa/anatomía & histología , Nervio Oftálmico/anatomía & histología , Procedimientos de Ortoqueratología/efectos adversos , Adulto , Estudios de Casos y Controles , Sensibilidad de Contraste/fisiología , Córnea/inervación , Córnea/fisiología , Femenino , Humanos , Masculino , Microscopía Confocal , Adulto Joven
7.
Ecotoxicol Environ Saf ; 140: 230-234, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28267652

RESUMEN

Use of avoidance tests is a quick and cost-effective method of assessing contaminants in soils. One option for assessing earthworm avoidance behavior is a two-section test, which consists of earthworms being given the choice to move between a test soil and a control substrate. For ecological relevance, tested soils should be field-contaminated soils. For practical reasons, artificial soils are commonly used as the control substrate. Interpretation of the test results compromised when the test soil and the artificial substrate differ in their physico-chemical properties other than just contaminants. In this study we identified the physico-chemical properties that influence avoidance response and evaluated the usefulness of adjusting these in the control substrate in order to isolate metal-driven avoidance of field soils by earthworms. A standardized two-section avoidance test with Eisenia fetida was performed on 52 uncontaminated and contaminated (Cu >155mgkg-1, As >19mgkg-1) agricultural soils from the Aconcagua River basin and the Puchuncaví Valley in Chile. Regression analysis indicated that the avoidance response was determined by soil organic matter (OM), electrical conductivity (EC) and total soil Cu. Organic matter content of the artificial substrate was altered by peat additions and EC by NaCl so that these properties matched those of the field soils. The resultant EC80 for avoidance (indicative of soils of "limited habitat") was 433mg Cu kg-1 (339 - 528mgkg-1 95% confidence intervals). The earthworm avoidance test can be used to assess metal toxicity in field-contaminated soils by adjusting physico-chemical properties (OM and EC) of the artificial control substrate in order to mimic those of the field-collected soil.


Asunto(s)
Agricultura , Metales Pesados/toxicidad , Minería , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Reacción de Prevención/efectos de los fármacos , Bioensayo/métodos , Chile , Ecosistema , Contaminación Ambiental/análisis , Suelo/química , Pruebas de Toxicidad/métodos
8.
AIDS Care ; 28(10): 1296-300, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27144427

RESUMEN

Late diagnosis (LD) of human immunodeficiency virus (HIV) infection continues to be a significant problem that increases disease burden both for patients and for the public health system. Guidelines have been updated in order to facilitate earlier HIV diagnosis, introducing "indicator condition-guided HIV testing". In this study, we analysed the frequency of LD and associated risk factors. We retrospectively identified those cases that could be considered missed opportunities for an earlier diagnosis. All patients newly diagnosed with HIV infection who attended Hospital La Princesa, Madrid (Spain) between 2007 and 2014 were analysed. We collected epidemiological, clinical and immunological data. We also reviewed electronic medical records from the year before the HIV diagnosis to search for medical consultations due to clinical indicators. HIV infection was diagnosed in 354 patients. The median CD4 count at presentation was 352 cells/mm(3). Overall, 158 patients (50%) met the definition of LD, and 97 (30.7%) the diagnosis of advanced disease. LD was associated with older age and was more frequent amongst immigrants. Heterosexual relations and injection drug use were more likely to be the reasons for LD than relations between men who have sex with men. During the year preceding the diagnosis, 46.6% of the patients had sought medical advice owing to the presence of clinical indicators that should have led to HIV testing. Of those, 24 cases (14.5%) were classified as missed opportunities for earlier HIV diagnosis because testing was not performed. According to these results, all health workers should pursue early HIV diagnosis through the proper implementation of HIV testing guidelines. Such an approach would prove directly beneficial to the patient and indirectly beneficial to the general population through the reduction in the risk of transmission.


Asunto(s)
Diagnóstico Tardío , Infecciones por VIH/diagnóstico , Adulto , Factores de Edad , Anciano , Recuento de Linfocito CD4 , Diagnóstico Precoz , Emigración e Inmigración , Femenino , Infecciones por VIH/sangre , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , España , Factores de Tiempo , Adulto Joven
9.
Ecotoxicol Environ Saf ; 122: 171-7, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26233921

RESUMEN

It has been argued that the identification of the phytotoxic metal thresholds in soil should be based on field-collected soil rather than on artificially-contaminated soils. However, the use of field-collected soils presents several difficulties for interpretation because of mixed contamination and unavoidable covariance of metal contamination with other soil properties that affect plant growth. The objective of this study was to estimate thresholds of copper phytotoxicity in topsoils of 27 agricultural areas historically contaminated by mining activities in Chile. We performed emergence and early growth (21 days) tests (OECD 208 and ISO 11269-2) with perennial ryegrass (Lolium perenne L.). The total Cu content in soils was the best predictor of plant growth and shoot Cu concentrations, while soluble Cu and pCu(2+) did not well correlate with these biological responses. The effects of Pb, Zn, and As on plant responses were not significant, suggesting that Cu is a metal of prime concern for plant growth in soils exposed to copper mining activities in Chile. The effects of soil nutrient availability and shoot nutrient concentrations on ryegrass response were not significant. It was possible to determine EC10, EC25 and EC50 of total Cu in the soil of 327 mg kg(-1), 735 mg kg(-1) and 1144 mg kg(-1), respectively, using the shoot length as a response variable. However, the derived 95% confidence intervals for EC10, EC25 and EC50 values of total soil Cu were wide, and thus not allowing a robust assessment of metal toxicity for agricultural crops, based on total soil Cu concentrations. Thus, plant tests might need to be performed for metal toxicity assessment. This study suggests shoot length of ryegrass as a robust response variable for metal toxicity assessment in contaminated soils with different nutrient availability.


Asunto(s)
Cobre/toxicidad , Lolium/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Agricultura , Chile , Intoxicación por Metales Pesados , Lolium/crecimiento & desarrollo , Minería , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/crecimiento & desarrollo , Intoxicación , Suelo
10.
Ecotoxicol Environ Saf ; 122: 448-54, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26398238

RESUMEN

Several previous studies highlighted the importance of using field-collected soils-and not artificially-contaminated soils-for ecotoxicity tests. However, the use of field-collected soils presents several difficulties for interpretation of results, due to the presence of various contaminants and unavoidable differences in the physicochemical properties of the tested soils. The objective of this study was to estimate thresholds of metal toxicity in topsoils of 24 agricultural areas historically contaminated by mining activities in Chile. We performed standardized earthworm reproduction tests (OECD 222 and ISO 11268-2) with Eisenia fetida. Total soil concentrations of Cu, As, Zn, and Pb were in the ranges of 82-1295 mg kg(-1), 7-41 mg kg(-1), 86-345 mg kg(-1), and 25-97 mg kg(-1), respectively. In order to differentiate between the effects of different metals, we used regression analysis between soil metal concentrations and earthworm responses, as well as between metal concentrations in earthworm tissues and earthworm responses. Based on regression analysis, we concluded that As was a metal of prime concern for Eisenia fetida in soils affected by Cu mining activities, while Cu exhibited a secondary effect. In contrast, the effects of Zn and Pb were not significant. Soil electrical conductivity was another significant contributor to reproduction toxicity in the studied soils, forcing its integration in the interpretation of the results. By using soils with electrical conductivity ≤ 0.29 dS m(-1) (which corresponds to EC50 of salt toxicity to Eisenia fetida), it was possible to isolate the effect of soil salinity on earthworm reproduction. Despite the confounding effects of Cu, it was possible to determine EC10, EC25 and EC50 values for total soil As at 8 mg kg(-1), 14 mg kg(-1) and 22 mg kg(-1), respectively, for the response of the cocoon production. However, it was not possible to determine these threshold values for juvenile production. Likewise, we were able to determine EC10, EC25 and EC50 of earthworm tissue As of 38 mg kg(-1), 47 mg kg(-1), and 57 mg kg(-1), respectively, for the response of the cocoon production. Finally, we determined the no-observed effect concentration of tissue As in E. fetida of 24 mg kg(-1). Thus, earthworm reproduction test is applicable for assessment of metal toxicity in field-collected soils with low electrical conductivity, while it might have a limited applicability in soils with high electrical conductivity because the salinity-induced toxicity will hinder the interpretation of the results.


Asunto(s)
Arsénico/toxicidad , Cobre/toxicidad , Minería , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Suelo/química , Animales , Arsénico/análisis , Chile , Cobre/análisis , Monitoreo del Ambiente , Oligoquetos/química , Oligoquetos/crecimiento & desarrollo , Reproducción/efectos de los fármacos , Contaminantes del Suelo/análisis
11.
J Vet Intern Med ; 38(1): 161-166, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38100467

RESUMEN

BACKGROUND: The utility of neutrophil-to-lymphocyte ratio (NLR), platelet to-lymphocyte ratio (PLR) and monocyte-to-lymphocyte ratio (MLR) as prognostic indicators has not been investigated in canine parvovirosis (CPV). HYPOTHESIS: To evaluate whether these hematological ratios obtained at hospital admission in CPV are associated with outcome or duration of hospitalization. ANIMALS: Four hundred one client-owned dogs presented with CPV. Methods-Retrospective multicenter cohort study. Medical records were reviewed to identify dogs with CPV. Data regarding signalment, complete blood count at admission, duration of hospitalization and outcome were collected. RESULTS: Of the 401 dogs included in the study, 336 (83.8%) survived to discharge. The median (25th and 75th percentiles) PLR in nonsurvivors (336.56 [159.84-635.77]) was significantly higher than in survivors (217.65 [117.67-389.65]) (P = .003). The area under the receiver-operating characteristic curve for nonsurvival was 0.615 (95% CI [0.593-0.691], P = .003). A cut off of 700 showed a 21.5% sensitivity and 90% specificity for nonsurvival. No association was observed between hospitalization duration and either hematological ratios or total WBC counts. The median (25th and 75th percentiles) lymphocyte count was below reference interval in all dogs and was significantly lower in the dogs which died (0.82 × 109 /L [0.5-1.87]) than in survivors (1.27 × 109 /L [0.73-2.22]) (P = .005). The median (25th and 75th percentiles) monocyte count however was lower in survivors (0.38 × 109 /L [0.29-1.59]), than in nonsurvivors (0.73 × 109 /L [0.1-2]) (P = .002). CONCLUSIONS: Evaluation of PLR at hospital admission might be a useful marker of disease severity and could have prognostic value in dogs with CPV.


Asunto(s)
Plaquetas , Linfocitos , Humanos , Perros , Animales , Estudios Retrospectivos , Estudios de Cohortes , Recuento de Leucocitos/veterinaria , Pronóstico , Neutrófilos
12.
Children (Basel) ; 11(2)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38397251

RESUMEN

BACKGROUND: Childhood myopia represents a global concern with increasing prevalence in recent decades. Lifestyle factors significantly impact myopia. AIM: To evaluate lifestyle factors in myopic children from a metropolitan area in Europe. METHODS: This was a descriptive study including myopic subjects aged 4-18 years. Patient demographic and clinical data were collected, including cycloplegic refraction in spherical equivalent refraction (SER) and axial length (AL). In addition, a questionnaire on lifestyle factors was conducted between September 2022 and April 2023. RESULTS: A total of 321 myopic children were included, aged 10.72 ± 3.05 years, of whom 51.4% were boys, with SER -2.25 ± 1.9 D and AL 24.54 ± 0.98 mm. The mean age of myopia onset was 7.69 ± 3.05 years. A total of 59.8% had family history of myopia. Those children who had <2 h/day of screen time (on weekdays) presented SER -2 ± 1.91 D, compared to those who had >2 h/day, SER: -2.50 ±1.88 D (p = 0.009). Children who spent <2 h/day doing near work after school were less myopic compared to those who spent >2 h/day (SER: -1.75 ± 1.83 vs. SER: -2.75 ± 1.82, respectively, p = 0.03). However, no significant association was observed between SER and AL and time spent outdoors nor between SER and AL and academic performance (p > 0.05). CONCLUSIONS: Screen time and near-work time appear to be lifestyle factors related to myopia.

13.
Graefes Arch Clin Exp Ophthalmol ; 251(9): 2171-9, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23657729

RESUMEN

BACKGROUND: To compare keratocyte density after mechanical microkeratome LASIK (MK-LASIK) and femtosecond-laser assisted LASIK (FS-LASIK). METHODS: We performed a prospective study of myopic patients that underwent MK-LASIK or FS-LASIK. We measured keratocyte density 3 and 15 months, and 3-5 years after the surgery using confocal microscopy, and compared them with healthy, non-operated corneas. RESULTS: Thirty-one eyes were included in the FS-LASIK group, 30 in the MK-LASIK group and 28 in the control group. Three months postoperatively, there was an increase in the keratocyte population of the whole cornea, mainly due to the mid and posterior stromal layers, in both treatment groups. It was also increased in the stromal bed after MK-LASIK, but not after FS-LASIK. In both groups, this was followed by a normalisation and stabilisation of cell density in those deeper layers 15 months after the surgery. Keratocyte density in the flap and stromal bed was decreased 15 months after FS- and MK-LASIK compared to 3 months postoperatively and compared to controls. It seemed to remain stable thereafter. In spite of this decrease, the average cell density throughout the cornea was not decreased compared to controls at any time point. CONCLUSION: We found a reorganization of keratocytes density after LASIK, with an initial increase, followed by a decrease in the stromal flap and stromal bed 15 months postoperatively, and stable from then onwards, but still maintaining normal average densities in the total cornea. There were no differences between MK- and FS-LASIK.


Asunto(s)
Queratocitos de la Córnea/patología , Queratomileusis por Láser In Situ/métodos , Láseres de Excímeros/uso terapéutico , Miopía/cirugía , Adulto , Recuento de Células , Paquimetría Corneal , Sustancia Propia/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Microscopía Confocal , Miopía/fisiopatología , Estudios Prospectivos , Colgajos Quirúrgicos/patología , Agudeza Visual/fisiología , Adulto Joven
14.
Graefes Arch Clin Exp Ophthalmol ; 251(11): 2575-84, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24008847

RESUMEN

BACKGROUND: Descemet membrane endothelial keratoplasty (DMEK) is being proposed as the procedure of choice in corneal endothelial disease as it achieves better visual and refractive outcomes than Descemet stripping automated endothelial keratoplasty (DSAEK). Nevertheless, primary graft failure is frequent, especially during the learning curve, and secondary back-up procedure consists on DSAEK. We aim to compare corneal haze and visual acuity of patients undergoing primary DSAEK vs. patients undergoing DSAEK as a back-up procedure after primary DMEK failure. METHODS: This study is a comparative case series that included 19 eyes from 16 patients with early stages of corneal failure and limitation of daily activities after primary DSAEK or secondary DSAEK. A control group of non-operated corneas included 10 aged-matched normal eyes. The study was conducted at University Hospital Ramón y Cajal and Vissum Hospital, Madrid, Spain. Corneal densitometry readings and postoperative best-corrected visual acuity in subjects with primary and secondary DSAEK were recorded 6 months after the surgery using the Pentacam Scheimpflug system (Oculus, inc.,Wetzlar, Germany). RESULTS: In primary DSAEK median densitometry values (range) were statistically significantly higher (p < 0.05) than normal subjects for the full thickness, posterior and anterior part of the paracentral cornea; and the anterior part of the central cornea. In secondary DSAEK, median densitometry values were statistically significantly higher than normal subjects at all levels of the central and paracentral cornea. In secondary DSAEK, median densitometry values (range) were statistically significantly higher than in primary DSAEK in the full-thickness, anterior part and interface of the central cornea and in the full-thickness and posterior part of the paracentral cornea. Median visual acuity between groups (p = 0.47) was statistically better for the primary DSAEK group, which also had a higher percentage of patients achieving BCVA of ≥ 20/40 and ≥ 20/25 than the secondary DSAEK group (100% vs. 62% and 60% vs. 0% respectively). CONCLUSIONS: There is an increase in central corneal light scattering after secondary DSAEK performed after a failed DMEK as compared to primary DSAEK. This has a negative impact on final visual acuity that needs to be considered in each patient when starting DMEK surgery.


Asunto(s)
Vesícula/cirugía , Opacidad de la Córnea/fisiopatología , Lámina Limitante Posterior/cirugía , Queratoplastia Endotelial de la Lámina Limitante Posterior , Endotelio Corneal/trasplante , Distrofia Endotelial de Fuchs/cirugía , Agudeza Visual/fisiología , Adulto , Anciano , Vesícula/fisiopatología , Córnea/patología , Enfermedades de la Córnea/fisiopatología , Enfermedades de la Córnea/cirugía , Densitometría , Femenino , Distrofia Endotelial de Fuchs/fisiopatología , Humanos , Luz , Masculino , Persona de Mediana Edad , Reoperación , Dispersión de Radiación , Insuficiencia del Tratamiento , Resultado del Tratamiento
15.
J Eye Mov Res ; 16(3)2023.
Artículo en Inglés | MEDLINE | ID: mdl-38111688

RESUMEN

This systematic review examines the use of eye-tracking devices in optometry, describing their main characteristics, areas of application and metrics used. Using the PRISMA method, a systematic search was performed of three databases. The search strategy identified 141 reports relevant to this topic, indicating the exponential growth over the past ten years of the use of eye trackers in optometry. Eye-tracking technology was applied in at least 12 areas of the field of optometry and rehabilitation, the main ones being optometric device technology, and the assessment, treatment, and analysis of ocular disorders. The main devices reported on were infrared light-based and had an image capture frequency of 60 Hz to 2000 Hz. The main metrics mentioned were fixations, saccadic movements, smooth pursuit, microsaccades, and pupil variables. Study quality was sometimes limited in that incomplete information was provided regarding the devices used, the study design, the methods used, participants' visual function and statistical treatment of data. While there is still a need for more research in this area, eye-tracking devices should be more actively incorporated as a useful tool with both clinical and research applications. This review highlights the robustness this technology offers to obtain objective information about a person's vision in terms of optometry and visual function, with implications for improving visual health services and our understanding of the vision process.

16.
Diagnostics (Basel) ; 13(20)2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37892009

RESUMEN

OBJECTIVE: To describe corneal confocal microscopy findings in patients with long COVID-19 with persistent symptoms over 20 months after SARS-CoV-2 infection. DESIGN: A descriptive cross-sectional study that included a total of 88 patients; 60 patients with Long COVID-19 and 28 controls. Long COVID-19 diagnosis was established according to the World Health Organization criteria. Corneal confocal microscopy using a Heidelberg Retina Tomograph II (Heidelberg Engineering, Heidelberg, Germany) was performed to evaluate sub-basal nerve plexus morphology (corneal nerve fiber density, nerve fiber length, nerve branch density, nerve fiber total branch density, nerve fiber area, and nerve fiber width). Dendritic cell density and area, along with microneuromas and other morphological changes of the nerve fibers were recorded. RESULTS: Long COVID-19 patients presented with reduced corneal nerve density and branch density as well as shorter corneal nerves compared to the control group. Additionally, Long COVID-19 patients showed an increased density of dendritic cells also with a greater area than that found in the control group of patients without systemic diseases. Microneuromas were detected in 15% of Long COVID-19 patients. CONCLUSIONS: Long COVID-19 patients exhibited altered corneal nerve parameters and increased DC density over 20 months after acute SARS-CoV-2 infection. These findings are consistent with a neuroinflammatory condition hypothesized to be present in patients with Long COVID-19, highlighting the potential role of corneal confocal microscopy as a promising noninvasive technique for the study of patients with Long COVID-19.

17.
PLoS One ; 18(6): e0286884, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37289791

RESUMEN

PURPOSE: To investigate the possible risk factors for treatment failure in patients who had undergone Preserflo Microshunt (PMS) implantation, using anterior-segment optical coherence tomography (AS-OCT) to analyze the internal structures of the bleb. METHODS: The PMS blebs of 54 patients were evaluated with AS-OCT. A mathematical model was used to calculate the total filtering surface of the episcleral fluid cavity (EFC) and the hydraulic conductivity (HC) of the bleb wall. Complete and qualified success were defined as IOP between 6 and 17 mmHg with or without glaucoma medication. The relation between baseline characteristics and probability of bleb success was analyzed by bivariate and multivariate logistic regression. The main outcome measures were mean bleb wall thickness (BWT), reflectivity (BWR), HC, mean horizontal and vertical diameter and total filtering surface (TFS) of the EFC. RESULTS: Blebs from 74% patients were considered as complete success and 26% as failure. BWR and BWT increased linearly up to the first year in both groups. BWR was higher in the group failure (p = 0.02) and BWT in the group success (p<0.001). EFC was wider and shorter in the success group (p = 0.009, p = 0.03). Higher TFS showed a negative correlation with IOP (r = -0.4, p = 0.002). Higher baseline IOP was associated with success of PMS by multivariate analysis (p = 0.01). Mean HC, 0.034 ± 0.008 (µL/min)/mm2/mmHg, was negatively correlated with bleb surface (r = -0.5, p<0.0001) and wall´s thickness (r = -0.3, p = 0.01). CONCLUSIONS: AS-OCT revealed that successful PMS blebs could show either thick hyporreflective walls or wide filtering surfaces with thin capsules. A higher baseline IOP increased the probability of surgical success.


Asunto(s)
Glaucoma , Trabeculectomía , Humanos , Trabeculectomía/métodos , Segmento Anterior del Ojo , Presión Intraocular , Conjuntiva/cirugía , Glaucoma/cirugía , Tomografía de Coherencia Óptica/métodos
18.
Vet Rec ; 192(10): e2683, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-36755402

RESUMEN

BACKGROUND: Myocarditis frequently occurs in canine leishmaniosis (CanL). Heart fatty acid-binding protein (HFABP) is a biomarker of myocardial damage. METHODS: This study aimed to compare HFABP concentration (HFABPc) in healthy dogs and dogs at different stages of CanL and evaluate the correlation of this biomarker with several clinicopathological and echocardiographic variables. Thirty-one dogs diagnosed with CanL and 10 healthy dogs were included. RESULTS: HFABPc was not statistically different (p > 0.05) between groups of dogs at different LeishVet stages of CanL or between groups with high versus low to intermediate serology titres. In 70% of CanL dogs, HFABPc was within the 95% confidence interval limits of the mean of healthy dogs. A moderate negative correlation with globulin (r = -0.519; p = 0.03) and haematocrit (HCT) (r = -0.538; p = 0.02) was observed. No other significant correlation (p > 0.05) was observed with any other variable. LIMITATIONS: Many statistical tests were performed, and therefore, type I error cannot be ruled out. CONCLUSION: HFABPc is not consistently elevated in dogs with CanL and is not associated with the severity of the disease, or most echocardiographic or clinicopathological variables studied. The correlation with globulin and HCT was not strong and not considered clinically significant. HFABPc lacks sufficient predictive capacity in dogs with CanL, discouraging further research or clinical use of this biomarker in this disease.


Asunto(s)
Enfermedades de los Perros , Leishmania infantum , Leishmaniasis Visceral , Leishmaniasis , Perros , Animales , Enfermedades de los Perros/diagnóstico , Leishmaniasis/veterinaria , Biomarcadores , Leishmaniasis Visceral/veterinaria
19.
Diagnostics (Basel) ; 13(1)2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36611338

RESUMEN

In vivo corneal confocal microscopy (IVCM) is a non-invasive ophthalmic imaging technique that provides images of the cornea at the cellular level. Despite the uses in ocular surface pathologies, in the last decades IVCM has been used to provide more knowledge in refractive surgery wound healing, in neuropathies diagnosis, etc. The observation of the corneal cells, both normal and inflammatory, and the possibility of quantification of the corneal nerve density with manual or automated tools, makes IVCM have a significant potential to improve the diagnosis and prognosis in several systemic and corneal conditions.

20.
J Optom ; 15(1): 78-87, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33750678

RESUMEN

PURPOSE: To investigate which baseline factors are predictive for success in controlling myopia progression in a group of children wearing MiSight Contact Lens (CLs). METHODS: Myopic patients (n=41) fitted with MiSight CLs and followed up two years were included in this study. Bivariate analysis, a logistic regression analysis (LG) and a decision tree (DT) approach were used to screen for the factors influencing the success of the treatment. To assess the response, axial length (AL) changes were considered as main variable. Patients were classified based on a specific range of change of axial length at the end of each year of treatment as "responders" (R) (AL change <0.11mm/per year) and "non-responders" (NR) (AL change ≥0.11mm/per year). RESULTS: Of a total of forty-one Caucasian patients treated with MiSight CLs, 21 and 16 were considered responders in the first and the second year of follow-up, respectively. LG analysis showed that the only factor associated with smaller axial length growth was more time spent outdoors (p=0.0079) in the first year of treatment. The decision tree analysis showed that in the responding group spending more than 3 and 4h outdoors per week was associated with the best response in the first year and in the second year of treatment respectively. CONCLUSIONS: The LR and the DT approach of this pilot study identifies time spent outdoors as a main factor in controlling axial eye growth in children treated with MiSight CLs.


Asunto(s)
Lentes de Contacto Hidrofílicos , Miopía , Longitud Axial del Ojo , Niño , Progresión de la Enfermedad , Humanos , Miopía/diagnóstico , Miopía/terapia , Proyectos Piloto , Refracción Ocular , España
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