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Tumor-derived extracellular vesicles (TEVs) induce the epithelial-to-mesenchymal transition (EMT) in nonmalignant cells to promote invasion and cancer metastasis, representing a novel therapeutic target in a field severely lacking in efficacious antimetastasis treatments. However, scalable technologies that allow continuous, multiparametric monitoring for identifying metastasis inhibitors are absent. Here, the development of a functional phenotypic screening platform based on organic electrochemical transistors (OECTs) for real-time, noninvasive monitoring of TEV-induced EMT and screening of antimetastatic drugs is reported. TEVs derived from the triple-negative breast cancer cell line MDA-MB-231 induce EMT in nonmalignant breast epithelial cells (MCF10A) over a nine-day period, recapitulating a model of invasive ductal carcinoma metastasis. Immunoblot analysis and immunofluorescence imaging confirm the EMT status of TEV-treated cells, while dual optical and electrical readouts of cell phenotype are obtained using OECTs. Further, heparin, a competitive inhibitor of cell surface receptors, is identified as an effective blocker of TEV-induced EMT. Together, these results demonstrate the utility of the platform for TEV-targeted drug discovery, allowing for facile modeling of the transient drug response using electrical measurements, and provide proof of concept that inhibitors of TEV function have potential as antimetastatic drug candidates.

Resumen Introducción: La baja visión y la ceguera tienen alta prevalencia mundial, siendo categorias de discapacidad frecuentes en Colombia. Se requieren estudios que caractericen la etiologia de las deficiencias visuales permanentes. Objetivo: Identificar y caracterizar las diferentes causas de baja visión y ceguera en siete centros de referencia para la población con discapacidad visual en Colombia, atendida entre los años 2012 a 2017 en seis ciudades capitales. Materiales y métodos: estudio retrospectivo, serie de casos, descriptivo y multicéntrico. Resultados: Se contó con una muestra de 879 registros de pacientes con discapacidad visual. El 70% (612/879) con baja visión y 30% (267/879) con ceguera. Para todos los grupos de edad es más prevalente la baja visión. La etiologia más frecuente en pacientes con baja visión fue la degeneración macular asociada a la edad (DMAE) (24%, 144/612); en pacientes con ceguera fue el glaucoma (17%, 45/267). Discusión: Posiblemente en Colombia las causas de baja visión y ceguera van más allá de las cataratas, errores de refracción no corregidos y ceguera infecciosa. Conclusiones: las etiologias más frecuentes encontradas son condiciones oculares crónicas y diversas, que requieren intervenciones especificas para disminuir su prevalencia y prevenir casos de baja visión y ceguera. Abstract Introduction: Low vision and blindness have high global prevalence, with categories of disability common in Colombia. Studies that characterize the etiology of permanent visual impairments are required. Objective: To identify and characterize the different causes of low vision and blindness in seven reference centers for the visually impaired population in Colombia, attended between 2012 and 2017 in six capital cities. Materials and methods: retrospective, case series, descriptive and multicenter study. Results: A sample of 879 records of visually impaired patients was available. Low vision is more prevalent for all age groups. 70% (612/879) low vision and 30% (267/879) blindness. The most common etiology in patients with low vision was age-related macular degeneration (DMAE) (24%, 144/612); in patients with blindness it was glaucoma (17%, 45/267). Discussion: Possibly in Colombia the causes of low vision and blindness go beyond cataracts, un corrected refractive errors and infectious blindness. Conclusions: The most common etiologies found are chronic and diverse eye conditions, which require specific interventions to decrease their prevalence and prevent cases of low vision and blindness. Resumo Introdujo: Baixa visáo e cegueira tém alta prevaléncia global, com categorías de incapacidade comuns na Colombia. Sao necessários estudos que caracterizem a etiologia das deficiencias visuais permanentes. Objetivo: Identificar e caracterizar as diferentes causas de baixa visao e cegueira em sete centros de referéncia para a populagáo deficiente visual na Colombia, atendidos entre 2012 e 2017 em seis capitais. Materiais e métodos: estudo retrospectivo, série de casos, descritivo e multicéntrico. Resultados: Uma amostra de 879 registros de pacientes com deficiéncia visual estava disponível. 54% (478/879) homens. A baixa visao é mais prevalente para todas as faixas etárias. 70% (612/879) baixa visao e 30% (267/879) cegueira. A etiologia mais comum em pacientes com baixa visáo foi a degenerado macular relacionada a idade (DMAE) (24%, 144/612); em pacientes com cegueira foi glaucoma (17%, 45/267). Discussao: Possivelmente na Colombia as causas da baixa visáo e cegueira váo além da catarata, erros refrativos náo corrigidos e cegueira infecciosa. Condusdes: As etiologias mais comuns encontradas sáo condigóes oculares crónicas e diversas, que requerem intervengóes específicas para diminuir sua prevaléncia e prevenir casos de baixa visáo e cegueira.

Cancer-derived exosomes (cEXOs) facilitate transfer of information between tumor and human primary stromal cells, favoring cancer progression. Although the mechanisms used during this information exchange are still not completely understood, it is known that binding is the initial contact established between cEXOs and cells. Hence, studying binding and finding strategies to block it are of great therapeutic value. However, such studies are challenging for a variety of reasons, including the need for human primary cell culture, the difficulty in decoupling and isolating binding from internalization and cargo delivery, and the lack of techniques to detect these specific interactions. In this work, we created a supported biomimetic stem cell membrane incorporating membrane components from human primary adipose-derived stem cells (ADSCs). We formed the supported membrane on glass and on multielectrode arrays to offer the dual option of optical or electrical detection of cEXO binding to the membrane surface. Using our platform, we show that cEXOs bind to the stem cell membrane and that binding is blocked when an antibody to integrin β1, a component of ADSC surface, is exposed to the membrane surface prior to cEXOs. To test the biological outcome of blocking this interaction, we first confirm that adding cEXOs to cultured ADSCs leads to the upregulation of vascular endothelial growth factor, a measure of proangiogenic activity. Next, when ADSCs are first blocked with anti-integrin β1 and then exposed to cEXOs, the upregulation of proangiogenic activity and cell proliferation are significantly reduced. This biomimetic membrane platform is the first cell-free label-free in vitro platform for the recapitulation and study of cEXO binding to human primary stem cells with potential for therapeutic molecule screening as it is compatible with scale-up and multiplexing.

Johanna Prüssmann-Uribe1,2 and amp; Iván Darío Correa-Arango1 1Área de Ciencias del Mar, Departamento de Geología, Facultad de Ingeniería, Universidad EAFIT, sede Medellín, A.A. 3300, 2Docente de cátedra, Universidad de Antioquia, Colombia jprussmann@eafit.edu.co, icorrea@eafit.edu.co Con el fin de generar información para el manejo integrado y el desarrollo sostenible de la franja litoral Caribe de los departamentos de Antioquia y Chocó, se creó una base de datos espacial llamada GEOURABÁ, a partir de la fotointerpretación y restitución de una ortofoto tomada en el año 2009; esta base de datos recopila la información geomorfológica a escala 1:10000, de los 600km del contorno litoral del sector en estudio, con una geomorfología sumamente variada que obedece a múltiples factores naturales y antrópicos, incluyendo: a) la litología y tectónica, b) los cambios en el nivel relativo del mar, c) la extracción de materiales de playas y zonas aledañas y d) el drenaje/colmatación de los pantanos de manglares.....