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INTRODUCCIÓN. La constante degradación de los suelos a nivel global es un problema de suma importancia, el cual en la actualidad se está afrontando con diversas propuestas de restauración, entre las cuales se encuentra el uso de la madera rameal fragmentada (MRF). OBJETIVO. La presente investigación analiza la variación de diferentes factores físicos y químicos que nos permiten inferir la viabilidad de la MRF como una propuesta para la enmienda edáfica de suelos degradados en los paisajes andinos. MÉTODO. Para ello se recolectaron muestras de suelo de dos parcelas, una con tratamiento y una sin tratamiento, muestras a las cuales se les realizó un análisis de fertilidad con cuyos resultados se procedió a analizar la variación temporal y espacial, utilizando un ANOVA y realizando una ponderación de distancia inversa (IDW) respectivamente. RESULTADOS. Nuestros resultados muestran una mejor condición y calidad del suelo en la parcela con tratamiento, así como diferencias significativas en los indicadores de calidad del suelo. DISCUSIÓN Y CONCLUSIONES. Los resultados obtenidos en esta investigación respaldan el uso de la MRF como una enmienda edáfica efectiva para el tratamiento de suelos andinos degradados.

Este editorial resume los 10 años de historia y los principales logros del Centro de Investigación de la Biodiversidad y Cambio Climático (BioCamb), de la Universidad Tecnológica Indoamérica. El BioCamb fue creado el 15 de julio del 2011, en respuesta a la necesidad de conocer la diversidad biológica del Ecuador, incluyendo su interrelación con el ser humano. Estos años ha publicado más de 140 artículos en revistas indexadas en Scopus con investigadores de 48 países, de 412 instituciones. Estas investigaciones se han centrado en Ecuador y en los Andes y han descrito 53 nuevas especies. El BioCamb, con la Facultad de Ciencias del Medio Ambiente, puso en marcha la Ingeniería en Biodiversidad y Recursos Genéticos, y las maestrías en Biodiversidad y Cambio Climático y en Gestión Ambiental. Además, ha impulsado la ciencia ciudadana, organizando, varios BioBlitz y el Desafío Naturaleza Urbana, y trabajos comunitarios integrados en proyectos de investigación o a través de la vinculación con la sociedad. El BioCamb ha conseguido integrar las tres funciones sustantivas de la educación superior, docencia, investigación y vinculación con la sociedad, aportando con conocimiento y profesionales que trabajen por el desarrollo sostenible de Ecuador y la conservación de su biodiversidad.

Bioblitz is a citizen global science initiative which aims to find and identify as many species of fauna and flora as possible in a specific area during a short period of time. This activity promotes the engagement of the public to learn about the biodiversity of a particular region, often in urban areas. The objective of this study was to do the first Bioblitz in Quito (Ecuador) to (1) survey the flora and fauna of Quito, specifically in the Guangüiltagua Metropolitan Park; and (2) engage citizens in such activity. This first Bioblitz, held on December 2, 2017, was organized by Universidad Tecnológica Indoamérica and Fundación Zoológica del Ecuador. The event was attended by 15 experts, 21 students, and 29 citizens, including two children under 10 years of age. Standard biological diversity assessment methods were used for amphibians, reptiles, birds, mammals, insects, aquatic macroinvertebrates, and plants. A total of 18 species of birds, two of amphibians, one reptile, 21 terrestrial invertebrates, two macroinvertebrates, one mammal, and 26 plant species were identified. This experience allowed the engagement of citizens to learn about the local biodiversity in their city.

Background: The standard treatment for prostate cancer (PCa) is androgen deprivation therapy (ADT) that blocks AR transcriptional activity, which is responsible to the initiation and progression of PCa. However, ADT invariably leads to the castration-resistant PCa (CRPC) with restored activity of AR. CRPC can be further treated with more intensive ADTs, including CYP17-inhibitors to block intratumoral androgen synthesis and more potent AR antagonist. By analyzing the tumor mRNA from a CRPC patient biopsy who developed resistance to CYP17-inhibitor treatment, we identified a novel nonsense AR mutation on ligand binding domain (Q784*), which produces a C-terminal truncated form of AR protein containing only a fraction of ligand binding domain (LBD) and may mimic the function of some AR splice variants. We hypothesized that AR-Q784* may gain the androgen-independent activity, or may enhance the transcriptional activity of full-length AR (AR-FL) under low androgen environment through dimerization with AR-FL. Method: Luciferase reporter assays were applied to assess the transcriptional activity of AR-Q784* in absence or presence of androgens, and with or without AR-FL. Immunoblotting and immunofluorescence assays were used to examine the protein stability and cellular localization of AR-Q784*. Chromatin immunoprecipitation assays were also used to assess the chromatin binding ability of AR-Q784*. Moreover, the stable cell line that expresses endogenous AR-FL and tetracycline-inducible AR-Q784* was generated to determine the transcription activity on AR target genes and assess the effects on cell proliferation, particularly under low dose androgen condition. Result: Although it was constitutively expressed in nucleus, AR-Q784* does not elicit transcriptional activity despite the conditions of ligands. However, when it was co-expressed with AR-FL, AR-Q784* can enhance AR-mediated transcriptional activity and thus increased PCa cell proliferation particularly under low androgen conditions. Mechanistically, AR-Q784* can dimerize with AR-FL, enhance DNA binding ability of AR-FL, and strengthen AR recruitment of p300 coactivator. Conclusion: We show that CYP17 inhibitor treatment in CRPC may select for a distinct class of AR mutations/variations, including nonsense (AR-Q784*) or point-deletion mutations within LBD and certain splice variants that only lose a fraction of LBD domain. This class of AR mutants/variants is transcriptionally inactive but can enhance the activity of AR-FL due to their abilities of constitutive DNA binding and dimerization with AR-FL. However, this enhancing activity of those AR mutants/variants can be prevented by antagonist treatments such as enzalutamide. Therefore, this study provides an additional rationale for treating PCa patients with combination therapy of abiraterone and enzalutamide, which may prevent the selection for such AR mutations/variations in CRPC. Citation Format: Dong Han, Jude Owiredu, Kevin Valencia, Changmeng Cai. A novel nonsense mutation in androgen receptor confers resistance to CYP17 inhibitor treatment in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4476. doi:10.1158/1538-7445.AM2017-4476