ABSTRACT
Resumen: El presente artículo identificó y evaluó, mediante la percepción ambiental con enfoque geográfico (PAEG), los impactos sociales y ambientales a nivel de comunidades derivados de la contaminación presente en el arroyo denominado el Riíto en Tonalá, Chiapas. Para ello, se aplicó una metodología mixta que comprendió la identificación de actores sociales, entrevistas y aplicación de encuestas estructuradas mediante procedimientos estadísticos en dos comunidades de la costa de Chiapas: Paredón y Tonalá. Este tipo de investigación, además, permitió identificar debilidades en la gobernanza y gestión de las instituciones presentes en la zona. Se evidenció que no logran dar una solución integral a un problema de agua que pone en riesgo la salud de las dos comunidades en estudio y mucho menos al medio ambiente de la microcuenca.
Abstract: This article identified and evaluated through Environmental Perception with a Geographical Approach (PAEG), the social and environmental impacts at the community level derived from the contamination present in the stream called El Riíto in Tonalá, Chiapas. For this, a mixed methodology was applied, which included from the identification of social actors, interviews and the application of structured surveys using statistical procedures in two communities on the Chiapas coast: Paredón and Tonalá. This type of research also allowed identifying weaknesses in the governance and management of the institutions present in the area, as they fail to provide a comprehensive solution to a water problem that puts the health of the two communities under study at risk, much less to the micro basin environment.
Subject(s)
Humans , Water Pollutants , City Planning , MexicoABSTRACT
Human small intestinal crypts are the source of intestinal stem cells (ISCs) that are capable of undergoing self-renewal and differentiation to an epithelial layer. The development of methods to expand the ISCs has provided opportunities to model human intestinal epithelial disorders. Human crypt samples are usually obtained from either endoscopic or discarded surgical samples, and are thereby exposed to warm ischemia, which may impair their in vitro growth as three-dimensional culture as spheroids or enteroids. In this study we compared duodenal samples obtained from discarded surgical samples to those isolated from whole-body preserved cadaveric donors to generate in vitro cultures. We also examined the effect of storage solution (phosphate-buffered saline or University of Wisconsin [UW] solution) as well as multiple storage times on crypt isolation and growth in culture. We found that intestinal crypts were successfully isolated from cadaveric tissue stored for up to 144 h post-procurement and also were able to generate enteroids and spheroids in certain media conditions. Surgical samples stored in UW after procurement were sufficiently viable up to 24 h and also allowed the generation of enteroids and spheroids. We conclude that surgical samples stored for up to 24 h post-procurement in UW solution allowed for delayed crypt isolation and viable in vitro cultures. Furthermore, in situ, hypothermic preservation in cadaveric duodenal samples permitted crypt/ISC isolation, and successful culture of spheroids and enteroids from tissues held for up to 6 days post-procurement.
Subject(s)
Cell Culture Techniques/methods , Intestines/physiopathology , Cadaver , Cell Differentiation , HumansABSTRACT
PURPOSE: Current culture schema for human intestinal stem cells (hISCs) frequently rely on a 3D culture system using Matrigel™, a laminin-rich matrix derived from murine sarcoma that is not suitable for clinical use. We have developed a novel 2D culture system for the in vitro expansion of hISCs as an intestinal epithelial monolayer without the use of Matrigel. METHODS: Cadaveric duodenal samples were processed to isolate intestinal crypts from the mucosa. Crypts were cultured on a thin coat of type I collagen or laminin. Intestinal epithelial monolayers were supported with growth factors to promote self-renewal or differentiation of the hISCs. Proliferating monolayers were sub-cultured every 4-5days. RESULTS: Intestinal epithelial monolayers were capable of long-term cell renewal. Less differentiated monolayers expressed high levels of gene marker LGR5, while more differentiated monolayers had higher expressions of CDX2, MUC2, LYZ, DEF5, and CHGA. Furthermore, monolayers were capable of passaging into a 3D culture system to generate spheroids and enteroids. CONCLUSION: This 2D system is an important step to expand hISCs for further experimental studies and for clinical cell transplantation. LEVEL OF EVIDENCE: 1 Experimental.
