The Short-term Effects of Artificial Tears on the Tear Film Assessed by a Novel High-Resolution Tear Film Imager: A Pilot Study.

PURPOSE: The purpose of this study was to investigate the effects of artificial tears (AT) on the sublayers of the tear film assessed by a novel tear film imaging (TFI) device. METHODS: The mucoaqueous layer thickness (MALT) and lipid layer thickness (LLT) of 198 images from 11 healthy participants, 9 of whom had meibomian gland disease, were prospectively measured before and after exposure to 3 different AT preparations (Refresh Plus; Retaine [RTA]; Systane Complete PF [SYS]), using a novel nanometer resolution TFI device (AdOM, Israel). Participants were assessed at baseline and at 1, 5, 10, 30, and 60 minutes after instilling 1 drop of AT during 3 sessions on separate days. Repeated-measures analysis of variances were used for comparisons with P < 0.05 considered significant. RESULTS: For all ATs, the mean MALT was greatest 1 minute after drop instillation, with an increase of 67%, 55%, and 11% above the baseline for SYS, Refresh Plus, and RTA, respectively. The SYS formulation demonstrated the highest percentage increases in mean MALT and LLT at most postdrop time points. The MALT differences were significantly higher in the SYS than in the RTA (P = 0.014). After 60 minutes, no AT group demonstrated statistically significant changes in MALT or LLT compared with baseline. CONCLUSIONS: We report, for the first time, the effects of AT on MALT and LLT using a high-resolution TFI. A substantial acute mean MALT increase occurs 1 minute after AT instillation with all agents tested, but there were clear differences in response and durability, suggesting the benefits of choosing specific AT according to the needs of each patient.

Conformational Changes of Poly(Maleic Anhydride-alt-styrene) Modified with Amino Acids in an Aqueous Medium and Their Effect on Cytocompatibility and Hemolytic Response.

The conformational changes of poly(maleic anhydride-alt-styrene) (PSMA) modified with different amino acids (PSMA-Aa) were studied in an aqueous medium as a function of ionic strength and pH. The specific viscosity of PSMA-Aa decreased with increasing salt concentration due to a more compact conformation. There was a decrease in surface tension with increasing concentrations of the modified polyelectrolyte having a greater effect for the PSMA modified with l-phenylalanine at pH 7.0, demonstrating a greater surface-active character. The conformational changes were also confirmed by molecular dynamics studies, indicating that PSMA-Aa exhibits a compact structure at pH 4.0 and a more extended structure at pH 7.0. On the other hand, the conformational changes of PSMA-Aa were related to its biological response, where the higher surface-active character of the PSMA modified with l-phenylalanine correlates very well with the higher hemolytic activity observed in red blood cells, in which the surface-active capacity supports lytic potency in erythrocytes. The cytocompatibility assays indicated that there were no significant cytotoxic effects of the PSMA-Aa. Additionally, in solvent-accessible surface area studies, it was shown that the carboxylate groups of the PSMA modified with l-phenylalanine are more exposed to the solvent at pH 7.0 and high salt concentrations, which correlates with lower fluorescence intensity, reflecting a loss of mitochondrial membrane potential. It is concluded that the study of the conformational changes in PE modified with amino acids is essential for their use as biomaterials and relevant to understanding the possible effects of PE modified with amino acids in biological systems.

Additional measures of macular function beyond visual acuity.

PURPOSE: Visual function is a complex process in which external visual stimuli are interpreted. Patients with retinal diseases and prolonged follow-up times may experience changes in their visual function that are not detected by the standard visual acuity measure, as they are a result of other alterations in visual function. With the advancement of different methods to evaluate visual function, additional measurements have become available, and further standardization suggests that some methods may be promising for use in clinical trials or routine clinical practice. The objectives of this article are to review these additional measurements and to provide guidance on their application. METHODS: The Vision Academy's membership of international retinal disease experts reviewed the literature and developed consensus recommendations for the application of additional measures of visual function in routine clinical practice or clinical trials. RESULTS: Measures such as low-luminance visual acuity, contrast sensitivity, retinal fixation and microperimetry, and reading performance are measures which can complement visual acuity measurements to provide an assessment of overall visual function, including impact on patients' quality of life. Measures such as dark adaptation, color vision testing, binocular vision testing, visual recognition testing, and shape discrimination require further optimization and validation before they can be implemented in everyday clinical practice. CONCLUSION: Additional measurements of visual function may help identify patients who could benefit from earlier diagnosis, detection of disease progression, and therapeutic intervention. New and additional functional clinical trial endpoints are required to fully understand the early stages of macular disease, its progression, and the response to treatment.

3-D OCT imaging of hyalocytes in partial posterior vitreous detachment and vaso-occlusive retinal disease.

Purpose: To describe the spatial distribution and morphologic characteristics of macrophage-like cells called hyalocytes in the posterior vitreous cortex of a patient with unilateral partial posterior vitreous detachment (PVD) using coronal plane en face optical coherence tomography (OCT). Observations: A 54-year-old male with sickle cell disease (HbSC genotype) presented with a partial PVD in one eye. Rendered volumes of a slab extending from 600 µm to 3 µm anterior to the inner limiting membrane (ILM) revealed hyperreflective foci in the detached posterior vitreous cortex suspended anterior to the macula, likely representing hyalocytes. In the fellow eye without PVD, hyperreflective foci were located 3 µm anterior to the ILM. The morphology of the cells in the eye with PVD varied between a ramified state with multiple elongated processes and a more activated state characterized by a plump cell body with fewer retracted processes. In the same anatomical location, the hyperreflective foci were 10-fold more numerous in the patient with vaso-occlusive disease than in an unaffected, age-matched control. Conclusions and Importance: Direct, non-invasive, and label-free techniques of imaging cells at the vitreoretinal interface and within the vitreous body is an emerging field. The findings from this case report suggest that coronal plane en face OCT can be used to provide a detailed and quantitative characterization of cells at the human vitreo-retinal interface in vivo. Importantly, this case report demonstrates that 3D-OCT renderings can enhance visualization of these cells in relation to the ILM, which may provide clues concerning the identity and contribution of these cells to the pathogenesis of vitreo-retinal diseases.

Posterior vitreous cortex hyalocytes visualization in asymmetric pigmented paravenous chorioretinal atrophy (PPCRA) using en face OCT.

Purpose: Pigmented paravenous chorioretinal atrophy (PPCRA) is a rare retinal disease with inflammatory or infectious associations affecting the retinal pigment epithelium (RPE) and choriocapillaris. While the clinical manifestations and imaging findings are well-documented in the literature, no reports exist describing potential biomarkers of intraocular inflammation or ischemia in this condition, such as the presence of posterior vitreous cortex hyalocytes. Observations: We report a case of a 26-year-old female who presented with progressive peripheral vision loss in both eyes over one year. Dilated fundus examination revealed bilateral, asymmetric bone-spicule pigmentary changes along the retinal veins, which appeared more advanced in the left eye. Optical coherence tomography (OCT) revealed the presence of numerous hyalocytes in both eyes 3 µm anterior to the inner limiting membrane (ILM). The morphology of the hyalocytes differed between the two eyes, suggesting different levels of activation related to the stage of the disease. Specifically, the left eye, with more advanced disease, exhibited hyalocytes with multiple elongated processes consistent with a quiescent state, whereas the right eye, with the less advanced disease state, exhibited amoeboid-appearing hyalocytes suggestive of more active inflammation. Conclusions: This case illustrates how hyalocyte morphology may reflect the underlying activity of an indolent retinal degeneration and provide a useful biomarker of disease progression.

Optical coherence tomography angiography as predictor of visual outcomes in retinal vein occlusion treated with antiangiogenic therapy.

PURPOSE: Evaluate optical coherence tomography angiography (OCT-A) features in retinal vein occlusions (RVO) associated with visual outcomes after anti-VEGF. METHODS: Analytical observational study performed in eyes with macular edema secondary to RVO treated with anti-VEGF, with at least 6 months of follow-up. Bradley et al. classification of macular ischemia was used. Logistic regression analysis was used to investigate associations between final best-corrected visual acuity (BCVA) and OCT-A. RESULTS: A total of 62 eyes, 61 subjects, mean age of 70 ± 12,6 years were included. Median follow up time 21,2 months (IQR 24.8), 53,2% had central retinal vein occlusion (CRVO) and 46,8% branch retinal vein occlusion (BRVO). Median BCVA pre-treatment was 0,84 logMAR (IQR 0,83) and post-treatment 0,47 logMAR (IQR 0,52). BCVA improved at the end of follow-up (p = 0,01), as well as central retinal thickness (CRT) (p = 0,02). Regarding capillary densities (CD), there was a decrease for both plexus, Superficial CD (p = 0,01) and Deep CD (p = 0,01), being more involved the superficial plexus. The lower the capillary density in both plexus, the worse BCVA, Superficial CD (r - 0,27, p = 0,03) and Deep CD (r - 0,29, p = 0,02). Media FAZ pre-treatment was 0,30 mm2 (IQR 0,23), with enlargement to 0,37 mm2 (IQR 0,32) (p = 0,01) post-treatment. Preservation of External Limiting Membrane/ Ellipsoid Zone (ELM/EZ) was seen in 60% of subjects (n = 37). The majority had grade 3 macular ischemia. Variables that best explain visual results were, baseline visual acuity (p = 0,01), pre-treatment CRT (p = 0,02) and pretreatment foveal superficial CD (p = 0,02). CONCLUSIONS: Variables that best explain final vision after anti-VEGF were baseline visual acuity, CRT and foveal superficial CD.

Flavoprotein fluorescence elevation is a marker of mitochondrial oxidative stress in patients with retinal disease.

Purpose: Recent studies of glaucoma, age-related macular degeneration, and diabetic retinopathy have demonstrated that flavoprotein fluorescence (FPF) can be utilized non-invasively as an indicator of mitochondrial oxidative stress in the retina. However, a comprehensive assessment of the validity and reliability of FPF in differentiating between healthy and diseased eyes across multiple disease states is lacking. Here, we evaluate the sensitivity and specificity of FPF in discriminating between healthy and diseased eyes in four leading causes of visual impairment worldwide, one of which has not been previously evaluated using FPF. We also evaluate the association between FPF and visual acuity. Methods: A total of 88 eyes [21 eyes of 21 unaffected controls, 20 eyes from 20 retinal vein occlusion (RVO) patients, 20 eyes from 20 diabetic retinopathy (DR) patients, 17 eyes from 17 chronic exudative age-related macular degeneration (exudative AMD) patients, and 10 eyes from 10 central serous retinopathy (CSR) patients] were included in the present cross-sectional observational study. Eyes were imaged non-invasively using a specially configured fundus camera OcuMet Beacon® (OcuSciences, Ann Arbor, MI). The macula was illuminated using a narrow bandwidth blue light (455 - 470 nm) and fluorescence was recorded using a narrow notch filter to match the peak emission of flavoproteins from 520 to 540 nm. AUROC analysis was used to determine the sensitivity of FPF in discriminating between diseased eyes and healthy eyes. Nonparametric Kruskal-Wallis Tests with post-hoc Mann Whitney U tests with the Holm-Bonferroni correction were performed to assess differences in FPF intensity, FPF heterogeneity, and best corrected visual acuity (BCVA) between the five groups. Spearman rank correlation coefficients were calculated to assess the relationship between FPF and BCVA. Results: AUROC analysis indicated that FPF intensity is highly sensitive for detecting disease, particularly for exudative AMD subjects (0.989; 95% CI = 0.963 - 1.000, p=3.0 x 107). A significant difference was detected between the FPF intensity, FPF heterogeneity, and BCVA in all four disease states compared to unaffected controls (Kruskal-Wallis Tests, p = 1.06 x 10-8, p = 0.002, p = 5.54 x 10-8, respectively). Compared to healthy controls, FPF intensity values were significantly higher in RVO, DR, exudative AMD, and CSR (p < 0.001, p < 0.001, p < 0.001, and p = 0.001, respectively). Spearman rank correlation coefficient between FPF intensity and BCVA was ρ = 0.595 (p = 9.62 x 10-10). Conclusions: Despite variations in structural retinal findings, FPF was found to be highly sensitive for detecting retinal disease. Significant FPF elevation were seen in all four disease states, with the exudative AMD patients exhibiting the highest FPF values compared to DR, CSR, and RVO subjects. This is consistent with the hypothesis that there is elevated oxidative stress in all of these conditions as previously demonstrated by blood studies. FPF intensity is moderately correlated with the late-in disease-marker BCVA, which suggests that the degree of FPF elevation can be used as a metabolic indicator of disease severity.

Sífilis gestacional y congénita en el Centro Hospitalario Pereira Rossell, 2020-2021 / Gestational and congenital syphilis at a children Hospital Center Pereira Rossell, 2020-2021 / Sifilis gestacional e congênita no Centro Hospitalar Pereira Rossell, 2020-2021

Introducción: la sífilis congénita es una entidad grave, que ocurre en recién nacidos de gestantes con sífilis no tratada o tratada inadecuadamente, que puede conducir a resultados adversos en el feto como abortos, óbitos, partos prematuros, bajo peso al nacer, infecciones sistémicas graves y muerte. Constituye un importante problema de salud pública a pesar de la disponibilidad de intervenciones costo-efectivas para evitar la transmisión materno fetal. Objetivos: determinar la prevalencia de sífilis gestacional e incidencia de sífilis congénita en el Centro Hospitalario Pereira Rossell en el periodo marzo 2020 - marzo 2021, año en el que se declaró la pandemia por COVID-19. Material y métodos: se realizó un estudio observacional, descriptivo en al cual fueron incluidas las mujeres embarazadas con diagnóstico de sífilis gestacional y neonatos con sífilis congénita. Resultados: se registró una prevalencia de sífilis gestacional de 27,5/1000 embarazadas y una incidencia de sífilis congénita de 1,37/1000 nacidos vivos. De los 161 recién nacidos 78 (48,4%) fueron considerados de alto riesgo de sífilis connatal por lo cual recibieron tratamiento y su internación se prolongó. Se observó un alto porcentaje de embarazos mal controlados y un bajo nivel de tratamiento a las parejas sexuales. Conclusiones: la prevalencia de sífilis gestacional en el Centro Hospitalario Pereira Rossell, en el período marzo 2020-marzo 2021, año de la pandemia por COVID-19; fue de 27,5/1000 embarazadas. Se confirmó aumento de la prevalencia con respecto al 20,8% reportado anteriormente. La incidencia de SC fue de 1,37/1000 nacidos vivos. Concomitante se observó una disminución en el control del embarazo y escaso tratamiento de las parejas sexuales. Se constata que aumentó el porcentaje de neonatos con alto riesgo de padecer sífilis connatal.

Introduction: syphilis is a preventable and treatable sexually transmitted disease that is a major public health problem. Transmission to the fetus, congenital syphilis, is serious and it is also the cause of abortions and deaths. Early and timely maternal diagno sis is a fundamental prevention tool. Objectives: to determine the prevalence of gestational syphilis and the incidence of congenital syphilis in the Pereira Rossell Hospital Center in the period March 2020-March 2021, the year in which the COVID-19 pandemic was declared. Material and Methods: an observational, descriptive study was carried out in which pregnant women diagnosed with gestational syphilis and neonates with congenital syphilis were included. Results: a prevalence of gestational syphilis of 27.5/1000 pregnant women and an incidence of congenital syphilis of 1.37/1000 live births were recorded of the 161 newborns, 78 (48.4%) of the neonates were considered to be at high risk of connatal syphilis, for which they received treatment and their hospital stay was prolonged. A high percentage of poorly controlled pregnancies and a low level of treatment for sexual partners were observed. Conclusions: the prevalence of gestational syphilis maintained an upward trend at the Pereira Rossell Hospital Center during the first year of the COVID-19 pandemic, mainly due to a significant decrease in pregnancy control, poor treatment of sexual partners and a high percentage of patients at high risk of unconfirmed connatal syphilis. After the first year of the COVID-19 Pandemic this rising trend still remains.

Introduccción: a sífilis é uma doença sexualmente transmissível, prevenível e tratável, que constitui um importante problema de saúde pública. Sua transmissão para o feto constitui uma entidade grave, a sífilis congênita, que é a causa de abortos e mortes. O diagnóstico materno precoce e oportuno é uma ferramenta fundamental de prevenção. Objetivos: determinar a prevalência de sífilis gestacional e incidência de sífilis congênita no Centro Hospitalar Pereira Rossell no período de março de 2020 a março de 2021, ano em que foi declarada a pandemia de COVID-19. Materiais e métodos: foi realizado um estudo observacional, descritivo, no qual foram incluídas gestantes com diagnóstico de sífilis gestacional e neonatos com sífilis congênita. Resultados: houve prevalência de sífilis gestacional de 27,5/1000 gestantes e incidência de sífilis congênita de 1,37/1000 nascidos vivos. Dos 161 recém nascidos, 78 (48,4%) dos neonatos foram considerados de alto risco para sífilis conatal para os quais receberam tratamento e sua internação foi prolongada. Observouse elevado percentual de gestações mal controladas e baixo nível de tratamento dos parceiros sexuais. Conclusões: a prevalência de sífilis gestacional no Centro Hospitalar Pereira Rossell no primeiro ano da pandemia de COVID-19 manteve a tendência ascendente, maiormente devido à diminuição significativa do controle da gravidez, mau tratamento dos parceiros sexuais e alta porcentagem de pacientes com alto risco de sífilis congênita não confirmada. A tendência ascendente ainda continua depois do primeiro ano da pandemia.

Central serous chorioretinopathy imaging biomarkers.

PURPOSE: To identify the factors predicting the visual and anatomical outcomes in eyes with central serous chorioretinopathy (CSCR) through 12 months. METHODS: Patients with diagnosis of CSCR, either acute or chronic, were included in this multicentric, retrospective study. Demographic factors; systemic risk factors; central macular thickness (CMT), subfoveal choroidal thickness (SFCT), linear extent of ellipsoid zone (EZ) and interdigitation zone damage on optical coherence tomography; details of leak on fluorescein angiography and indocyanine green angiography were included as predictors of anatomical and visual outcomes. Regression analysis was performed to correlate the changes in best corrected visual acuity (BCVA) and resolution of disease activity. RESULTS: A total of 231 eyes of 201 patients with a mean age (49.7±11.8 years) were analysed. A total of 97 and 134 eyes were classified as acute and chronic CSCR. BCVA (0.35±0.31 to 0.24±0.34; p<0.001), baseline optical coherence tomography (OCT) parameters including CMT (p<0.001), subretinal fluid (SRF) height (p<0.001) and SFCT (p=0.05) showed a significant change through 12 months. Multivariate regression analysis showed change in CMT (p≤0.01) and SRF height at baseline (p=0.05) as factors predictive of good visual outcome. Logistic regression analysis revealed changes in both CMT (p=0.009) and SFCT (p=0.01) through 12 months to correlate with the resolution of disease. CONCLUSION: OCT parameters such as changes in both CMT and SFCT along with subfoveal EZ damage can be predictive of disease resolution whereas changes in CMT and baseline SRF height correlate well with changes in BCVA through 12 months.

Evaluación de medidas morfométricas de tendones y ligamentos metacarpales palmares por ultrasonografía en caballos criollos colombianos / Evaluation of morphometric measures of tendons and metacarpal ligaments by ultrasonography in Colombian creole horses

RESUMEN Objetivo. Determinar los parámetros morfométricos ultrasonográficos de los tendones y ligamentos metacarpales palmares de caballos criollos colombianos clínicamente sanos. Materiales y métodos. Treinta caballos criollos colombianos clínicamente sanos de 6.4 ± 2.5 años se evaluaron en diferentes zonas del departamento de Córdoba (Colombia). Se midieron las variables área transversal (cm2), ancho latero medial (ALM) (cm) y espesor dorso palmar (EDP) (cm) en las estructuras de la región metacarpiana en los dos miembros anteriores mediante ultrasonografía. Resultados. La ecografía reveló que el área transversal del ligamento suspensorio fue la estructura de mayor área en las regiones proximales (1A, 1B y 2A), tanto para la extremidad izquierda como para la derecha. Por otro lado, no hubo una diferencia significativa (p>0.05) entre la extremidad izquierda y derecha para las mediciones de las estructuras en cualquier zona, y no hubo una diferencia significativa entre los grupos de edades e índice de masa corporal (IMC) de los caballos. Conclusiones. Se obtuvieron valores de referencia para los tendones y ligamentos en la región metacarpiana palmar en equinos proporcionando una guía de referencia cuando se sospechan condiciones patológicas metacarpo en equinos.

ABSTRACT Objective. To determine the ultrasonographic morphometric parameters of the palmar metacarpal tendons and ligaments of clinically healthy Colombian creole horses. Materials and methods. Thirty clinically healthy Colombian creole horses of 6.4 ± 2.5 years were evaluated in different areas of the department of Córdoba (Colombia). The variables cross-sectional area (cm2), medial lateral width (ALM) (cm) and dorsal palmar thickness (EDP) (cm) in the structures of the metacarpal region in the two anterior members were measured by means of ultrasound. Results. Ultrasonography revealed that the transverse area of the suspensory ligament was the structure with the largest area in the proximal regions (1A, 1B and 2A), for both the left and right limbs. On the other hand, there was no significant difference (P> 0.05) between left and right limb for measurements of structures in any area, and there was no significant difference between age groups and body mass index (BMI) of horses. Conclusions. Reference values for tendons and ligaments in the palmar metacarpal region were obtained in equines providing a reference guide when metacarpal pathological conditions in equines are suspected.

Characteristics of Pediatric Glaucoma in a Latin American Reference Center.

AIM: To describe the clinical and epidemiological characteristics of children with pediatric glaucoma (PG) treated in an ophthalmologic national reference center. MATERIALS AND METHODS: A retrospective study of patients diagnosed with PG in a national ophthalmologic reference center was made, between 2005 and 2015. Clinical findings, type of treatment, and the follow-up were evaluated. RESULTS: A total of 89 patients (145 eyes) were included. The median age of diagnosis was 2.0 years. The most frequent type of glaucoma was primary PG with 67.4% of affected patients, primary congenital glaucoma (PCG) being more frequent (69 eyes) than juvenile open-angle glaucoma (JOAG 36 eyes). Secondary PG accounted for 32.6% of the cases (40 eyes). At least one surgical procedure was needed in 56.6% of all studied eyes, and 10.7% of eyes had more than two surgical procedures. Even more, eyes with PCG had surgery in 88.4% of cases. On the contrary, eyes with JOAG did not require surgery. In the last assessment, the distribution of cases according visual acuity did not show differences. However, it is important to note that patients with secondary PG maintained a good vision only in 17.9% of cases. CONCLUSION: Pediatric glaucoma is a heterogeneous group of diseases, and due to its low incidence, descriptive reports of large cohorts are not available. This study has a well-detailed report of PG characteristics in a national reference center. The frequency of JOAG in the present study was significantly higher than that reported in other studies. Also, clinical characteristics of all glaucoma described have some differences from data published. CLINICAL SIGNIFICANCE: There are few studies that describe characteristics of PG. This study is an important tool to analyze the characteristics of PG in an effort to better know the disease. HOW TO CITE THIS ARTICLE: Saavedra C, Rios HA, Belalcazar S, et al. Characteristics of Pediatric Glaucoma in a Latin American Reference Center. J Curr Glaucoma Pract 2020;14(1):10-15.

Severe acute multi-systemic failure with bilateral ocular toxoplasmosis in immunocompetent patients from urban settings in Colombia: Case reports.

PROPOSE: To report two cases of severe acute multi-systemic failure with bilateral ocular toxoplasmosis in immunocompetent patients from urban settings in Colombia. OBSERVATIONS: We report two immunocompetent male patients aged 44- and 67-years-old who, despite not having visited the Amazonian region in Colombia, had severe bilateral posterior uveitis and extensive-bilateral macular lesions and multiple organ failure that required admission to an intensive care unit. Toxoplasma gondii was positive by PCR assay in vitreous humor samples. Patients were treated with intravitreal clindamycin and dexamethasone in addition to systemic treatment with trimethoprim-sulfamethoxazole. In both patients, infection by atypical strains was confirmed; in one case by serotyping and in another one by genotyping (ROP 18 virulent allele). After 2 and 4 months of treatment respectively, the patients showed improvement of the posterior uveitis and its systemic manifestations. However, there was no significant visual acuity improvement due to bilateral extensive macular involvement. CONCLUSIONS AND IMPORTANCE: Clinicians should be aware that toxoplasmosis originating from South America could be associated with severe acute multisystemic and intraocular bilateral involvement, even in patients with no history of exposure to jungle environments.

Contextos de interacción educativa y desarrollo de niños preescolares / Educational interaction and development contexts in pre-school children

Este artículo establece relaciones entre el desarrollo cognitivo de 405 niños1 de 3, 4 y 5 años y sus contextos educativos en la modalidad Hogares Comunitarios del Instituto Colombiano de Bienestar Familiar (HC-ICBF). Desde el enfoque sistémico de U. Bronfenbrenner se establecen relaciones entre indicadores de desarrollo de los niños y los descriptores de los contextos educativos denominados HC - ICBF. Los indicadores se establecen a partir de niveles diferenciados de estrategias de inferencia en la resolución de un problema, anclado a prácticas culturales específicas. Estadísticas no paramétricas y análisis de correspondencia múltiples (ACM) permitieron establecer que el desarrollo cognitivo de los niños preescolares tiene relaciones significativas con las expectativas que el cuidador tiene respecto de la educación de los niños. Estos datos dialogan con perspectivas de la psicología del desarrollo que vinculan los procesos de construcción de conocimiento a contextos culturales específicos

This article links the cognitive development of 405 children between 3 and 5 years old and their educational contexts under the modality of Community Homes of the Colombian Institute of Family Wellbeing (HC-ICBF). The systemic approach of Bronfenbrenner University establishes relations between development indicators of children and the descriptors of educational contexts called HC-ICBF. Indicators are established based on differentiated levels of inference strategies for problem resolutions concerning specific cultural practices. Non-parametric statistics and multiple correspondence analysis helped to determine that cognitive development of pre-school children have significant relationships with the expectation the caregiver has about children's education. These data relate to the approaches to developmental psychology that associate the knowledge construction processes with specific cultural contexts

Aproximaciones a estudios sobre la Burla desde la Perspectiva del Desarrollo / Mockery Studies from a Development Perspective

La burla emerge como una acción simbólica en la relación burlón-burlado. Usualmente se expresa en la modalidad hostil o en la modalidad amigable. El propósito de este artículo es reflexionar acerca de la noción de desarrollo que subyace a los estudios de la burla. Para cumplir con este objetivo se adoptaron los postulados de Jaan Valsiner acerca de los axiomas que conducen la investigación y las matrices de pensamiento psicológico que dan sentido a la re-organización de las teorías del desarrollo en tres modelos: Diferenciación, Equilibración y Enseñanza-aprendizaje. La revisión muestra una distribución de los estudios de la burla en el axioma no evolutivo y en el axioma evolutivo. Los estudios en el axioma evolutivo se caracterizan por la identificación de capacidades y habilidades cognitivas y sociales que se complejizan con la edad. En esta modalidad de trabajos se subordina la expresión de la burla respecto a otras expresiones humorísticas como el sarcasmo, la sátira y la ironía. Los referentes teórico-metodológicos de los estudios en el axioma evolutivo se aproximan al Modelo por Equilibración. Las conclusiones señalan la pertinencia de sostener la coherencia de las matrices de pensamiento psicológico en las investigaciones que indagan problemáticas del desarrollo.

The teasing emerges as a symbolic action in the interaction between a teaser and teased. It is Usually expressed in a hostile or in a friendly mode. The purpose of this article is to reflex about the development concept that underlies the teasing studies. To fulfill this objective, we were adopted Jaan Valsiner's postulates about the guided axioms in the developing research and also we adopted the psychological thought matrices that give meaning to the re-organization of theories of development in three models: Differentiation, Balance and Teaching and Learning. The review shows a distribution of studies of teasing in the evolutive axiom. The studies in the evolutive axiom are characterized by the identification of cognitive and social capabilities and abilities which complexitfy with the age. In this type of researches the teasing expression is subordinated respect to other humoristic expression as: the sarcasm, the satire and the irony. The theorical ­ methodological referents in the evolutive axiom are approach to the Balance Model. The conclusion focus on the pertinence to hold coherence in the psychological thought matrices for the researches that inquire in the development subject.

Lens changes in cardiovascular catheterization laboratories staff / Cambios en el cristalino en personal de laboratorio de cateterismo cardiovascular

Abstract Objective: To determine the association between occupational ionizing radiation exposure in the cardiovascular catheterization laboratories staff and development of lens changes. Methods: A cross-sectional study was made. Participants were recruited at the XIII Colombian Conference of Interventional Cardiology and SOLACI conferences in Bogotá - Colombia 2017. Informed consent was obtained from all study participants. Demographics and clinical data were collected. Associated lens changes were determined according to the ionizing radiation exposure status. Results: A total of 89 subjects (178 eyes) participated in the study. In general, the mean age was 40 years old, ranging from 19 to 78 years old. Distribution according gender was 55.3% male and 44.7% female. 31 subjects (62 eyes) were deemed to have not occupational exposure to radiation and 58 subjects (116 eyes) with a history of occupational radiation exposure. Exposed eyes had twice risk for present subcapsular posterior lens opacity compared to non-exposed eyes. The subjects with older age and physician role were associated to the presence of lens opacity, with a p value 0.001 in both cases. Likewise, exposed subjects with any lens opacity had a high mean occupational lifetime, with a p 0.001. Conclusions: This study confirms a statistically significant increase in radiation-associated subcapsular lens changes in the eyes of interventional cardiology staff compared to unexposed controls.

Resumen Objetivo: Determinar la asociación entre la exposición a radiación ionizante en el personal de las salas de cateterismo cardiovascular y el desarrollo de cambios en el cristalino. Métodos: Se hizo un estudio transversal. Los participantes fueron reclutados en el XIII Congreso Colombiano de Cardiología Intervencionista y las Conferencias SOLACI en Bogotá - Colombia 2017. Se obtuvo el consentimiento informado de todos los participantes. Se recolectaron datos demográficos y clínicos. Se determinó la asociación entre los cambios en el cristalino y la exposición a la radiación ionizante. Resultados: Un total de 89 sujetos (178 ojos) participaron en el estudio. En general, la edad promedio fue de 40 años, con edades comprendidas entre los 19 años y 78 años. La distribución según el género fue del 55,3% en hombres y el 44,7% en mujeres. Se consideró que 31 sujetos (62 ojos) no tenían exposición ocupacional a la radiación y 58 sujetos (116 ojos) presentaban exposición ocupacional a esta. Los ojos expuestos tenían dos veces el riesgo de presentar opacidad subcapsular posterior del cristalino en comparación con los ojos no expuestos. Los sujetos de mayor edad y con rol de médico se asociaron a la presencia de opacidad del cristalino, con un valor p de 0.001 en ambos casos. Del mismo modo, los sujetos expuestos con cualquier opacidad del cristalino tenían una vida laboral más larga, con una p 0.001. Conclusiones: Este estudio confirma un aumento estadísticamente significativo en la presencia de cambios en el cristalino en el personal de las salas de cateterismo cardiovascular en comparación con los controles no expuestos.

Surfaces based on amino acid functionalized polyelectrolyte films towards active surfaces for enzyme immobilization.

Surface based on polyelectrolytes functionalized with amino acids onto amino-terminated solid surfaces of silicon wafers was prepared, with the purpose of evaluate the chemical functionality of the polyelectrolyte films in adsorption and catalytic activity of an enzyme. In this work, the adsorption of the enzyme glucose 6-phosphate dehydrogenase from Leuconostoc mesenteroides (LmG6PD) was studied as model. The polyelectrolytes were obtained from poly (maleic anhydride-alt-vinylpyrrolidone) [poly(MA-alt-VP)] and functionalized with amino acids of different hydropathy index: glutamine (Gln), tyrosine (Tyr) and methionine (Met). The polyelectrolytes were adsorbed onto the amino-terminated silicon wafer at pH 3.5 and 4.5 and at low and high ionic strength. At low ionic strength and pH 3.5, the largest quantity of adsorbed polyelectrolyte was on the films containing glutamine moiety as the most hydrophilic amino acid in the side chain of polymer chain (5.88 mg/m2), whereas at high ionic strength and pH 4.5, the lowest quantity was in films containing tyrosine moiety in the side chain (1.88 mg/m2). The films were characterized by ellipsometry, contact angle measurements and atomic force microscopy (AFM). The polyelectrolyte films showed a moderate degree of hydrophobicity, the methionine derivative being the most hydrophobic film. With the aim of evaluate the effect of the amino acid moieties on the ability of the surface to adsorb enzymes, we study the activity of the enzyme on these surfaces. We observed that the polarity of the side chain of the amino acid in the polyelectrolyte affected the quantity of LmG6PD adsorbed, as well as its specific activity, showing that films prepared from poly(MA-alt-VP) functionalized with Met provide the best enzymatic performance. The results obtained demonstrated that the surfaces prepared from polyelectrolytes functionalized with amino acids could be an attractive and simple platform for the immobilization of enzymes, which could be of interest for biocatalysis applications.

Classification of diabetes-related retinal diseases using a deep learning approach in optical coherence tomography.

BACKGROUND AND OBJECTIVES: Spectral Domain Optical Coherence Tomography (SD-OCT) is a volumetric imaging technique that allows measuring patterns between layers such as small amounts of fluid. Since 2012, automatic medical image analysis performance has steadily increased through the use of deep learning models that automatically learn relevant features for specific tasks, instead of designing visual features manually. Nevertheless, providing insights and interpretation of the predictions made by the model is still a challenge. This paper describes a deep learning model able to detect medically interpretable information in relevant images from a volume to classify diabetes-related retinal diseases. METHODS: This article presents a new deep learning model, OCT-NET, which is a customized convolutional neural network for processing scans extracted from optical coherence tomography volumes. OCT-NET is applied to the classification of three conditions seen in SD-OCT volumes. Additionally, the proposed model includes a feedback stage that highlights the areas of the scans to support the interpretation of the results. This information is potentially useful for a medical specialist while assessing the prediction produced by the model. RESULTS: The proposed model was tested on the public SERI-CUHK and A2A SD-OCT data sets containing healthy, diabetic retinopathy, diabetic macular edema and age-related macular degeneration. The experimental evaluation shows that the proposed method outperforms conventional convolutional deep learning models from the state of the art reported on the SERI+CUHK and A2A SD-OCT data sets with a precision of 93% and an area under the ROC curve (AUC) of 0.99 respectively. CONCLUSIONS: The proposed method is able to classify the three studied retinal diseases with high accuracy. One advantage of the method is its ability to produce interpretable clinical information in the form of highlighting the regions of the image that most contribute to the classifier decision.

Genetic association with intravitreal ranibizumab response for neovascular age-related macular degeneration in Hispanic population.

BACKGROUND/PURPOSE: Age-related macular degeneration (AMD) is the leading cause of visual impairment in patients over 55 years. Currently, the most common therapies for neovascular AMD (nAMD) are intravitreal antiangiogenics. Studies suggest that genetic factors influence on antiangiogenics therapy outcomes. The purpose of this work was to establish the association between complement factor H (CFH) (Y402H), age-related maculopathy susceptibility 2 (ARMS2) (A69S), and high-temperature requirement factor A1 (HTRA1) (rs11200638) polymorphisms and the response to treatment with ranibizumab in patients with nAMD. METHODS: A cross-sectional study with 61 eyes with nAMD treated with ranibizumab was performed. Association between polymorphisms from CFH, ARMS2, and HTRA1 with the response to treatment was established. RESULTS: The mean age of patients was 76.6 (51-91) years. Only 37.7% of patients had a functional response and 26.2% had an anatomic response. TT polymorphism Y402H from CFH gene was associated with an increased likelihood of functional response to treatment. Otherwise, there was not a statistically significant association between anatomic and functional response to gene polymorphisms rs11200638 from HTRA1 and rs10490924 from ARMS 2. CONCLUSIONS: This study suggests that the response to intravitreal antiangiogenic therapy with ranibizumab was not associated to main polymorphisms from genes HTRA1 and ARMS2. However, it was found that the response to treatment differed according to CFH genotype, suggesting that further investigations are needed to establish if patients with the CC and TC genotype may need to be monitored more closely for disease recurrence than the TT genotype.

Inhibiting Pathogen Surface Adherence by Multilayer Polyelectrolyte Films Functionalized with Glucofuranose Derivatives.

Inhibiting pathogenic bacterial adherence on surfaces is an ongoing challenge to prevent the development of biofilms. Multilayer polyelectrolyte films are feasible antibacterial materials. Here, we have designed new films made of carbohydrate polyelectrolytes to obtain antibacterial coatings that prevent biofilm formation. The polyelectrolyte films were constructed from poly(maleic anhydride- alt-styrene) functionalized with glucofuranose derivatives and quaternized poly(4-vinylpyridine) N-alkyl. These films prevent Pseudomonas aeruginosa and Salmonella Typhimurium, two important bacterial contaminants in clinical environments, from adhering to surfaces. When the film was composed of more than 10 layers, the bacterial population was greatly reduced, while the bacteria remaining on the film were morphologically damaged, as atomic force microscopy revealed. The antibacterial capacity of the polyelectrolyte films was determined by the combination of thickness, wettability, surface energy, and most importantly, the conformation that polyelectrolytes adopt the function of nature of the carbohydrate group. This polyelectrolyte film constitutes the first green approach to preventing pathogenic bacterial surface adherence and proliferation without killing the bacterial pathogen.

Determinación de la curva de crecimiento en ovinos criollos de pelo, mediante la utilización del modelo gompertz, en el trópico bajo colombiano / Growth curve determination for creole hair sheep using the gompertz model in the low colombian tropic

En Colombia existe una diversidad de ovinos, denominados ovinos criollos, resultado del cruce de diferentes razas, desde la época de la colonización y que se adaptaron a diferentes regiones del país. En el caso particular de este estudio, se hace referencia a los ovinos criollos de pelo, que se acomodaron a las condiciones biogeográficas de la Costa Caribe colombiana. Estos animales, por su adaptabilidad, han tenido un importante papel en el desarrollo de la ovinocultura del país; sin embargo, es muy poca la información que se tiene, a nivel nacional, sobre las características crecimiento de la raza o especie. El objetivo del presente estudio fue determinar la curva de crecimiento de dos poblaciones de ovinos criollos del trópico bajo colombiano, a través del uso del modelo no lineal Gompertz. Se utilizaron 55 animales, con 13 pesajes cada uno, perteneciente a dos sistemas de producción del departamento de Córdoba, Colombia. Se realizó un ajuste del modelo, mediante el procedimiento NLIN de Statistical Analysis Software (SAS), para la estimación de los parámetros del modelo. Se estimó β0, β1 y β2, cuyos valores fueron 25,97 ± 9,3, 2,1 ± 0,5 y 0,010 ± 0,004, respectivamente. Los estimados de madurez a los 4 y 6 meses fueron de 55,8 y 70,6%, respectivamente, y la edad al 75 de madurez fue de 7,0 meses y al 95% de madurez, de 13,1 meses. El modelo de Gompertz permitió describir el crecimiento de ovinos criollos, en condiciones de pastoreo, en el trópico bajo.

The Colombian Creole sheep has an important role in the development of sheep farming in the country, as this breed is distributed in most of the territory, being animals with significant features that make it widely used in farms with different productive purposes. To assess growth characteristics in animals have been used mathematical models, which describe the relationship between the age of the animal, its rate of growth and maturity. These models are equations that allow the construction of continuous curves of one biological variable according to another. This study aimed to determine the growth curve of two populations of crossbred sheep through the use of nonlinear Gompertz model. 55 animals with 13 measures of weight each were used, pertaining to two production systems of the department of Córdoba, Colombia. Estimaste for β0, β1 y β2 were 25.97 ± 9.3, 2.1 ± 0.5 and 0.010 ± 0.004, respectively. Estimates of maturity at 4 and 6 months were 55.8 and 70.6%, respectively; age 75% of maturity was of 7.0 months and at 95% of maturity was of 13.1 months. Gompertz model allowed describing the growth of creole sheep in conditions of grazing in the low tropics.