El tratamiento de la especificidad de riegos de tortura y malos tratos a mujeres privadas de la libertad en las visitas realizadas por el Subcomité de Prevención de la Tortura (2007-2013)

En este artículo me enfoco en analizar el tratamiento que el Subcomité de Prevención de la Tortura de la Organización de Naciones Unidas ha dado en sus informes de visitas públicos a los riesgos específicos de sufrir malos tratos y tortura en el caso de mujeres privadas de la libertad utilizando aportes de metodologías feministas para el análisis de género del derecho. Para el efecto he estudiado las normas internacionales más pertinentes para el mandato de visitas que cumple el Subcomité en contraste con los hallazgos y recomendaciones realizados por este órgano de tratado en la visita a 11 Estados parte de los cinco continentes. Finalmente he ubicado los límites y aportes encontrados con relación a la prevención de la tortura y los malos tratos en mujeres privadas de la libertad y he propuesto algunos elementos a tener en cuenta para la inclusión de un enfoque de género en la labor de visitas del Subcomité.

El tratamiento de la especificidad de riegos de tortura y malos tratos a mujeres privadas de la libertad en las visitas realizadas por el Subcomité de Prevención de la Tortura (2007-2013)

En este artículo me enfoco en analizar el tratamiento que el Subcomité de Prevención de la Tortura de la Organización de Naciones Unidas ha dado en sus informes de visitas públicos a los riesgos específicos de sufrir malos tratos y tortura en el caso de mujeres privadas de la libertad. Este análisis se aborda desde aportes de metodologías feministas para el análisis de género del derecho. Para el efecto he estudiado las normas internacionales más pertinentes en relación con el mandato de visitas que cumple el Subcomité en contraste con los hallazgos y recomendaciones realizados por este órgano de tratado en la visita a once Estados parte de los cinco continentes. Finalmente he ubicado los límites y aportes encontrados con relación a la prevención de la tortura y los malos tratos en mujeres privadas de la libertad y he propuesto algunos elementos a tener en cuenta para la inclusión de un enfoque de género en la labor de visitas del Subcomité.

El tratamiento del delito de pornografía infantil en la legislación ecuatoriana

No hay equívoco al afirmar que la internet, así como el avance de las tecnologías de la información y comunicación han bridando a la humanidad significativos beneficios. Hoy imaginarse un mundo sin internet es impensable. Casi dos mil millones de habitantes del planeta están conectados a la red, y en todos los sectores de la sociedad se han utilizado estos medios para el desarrollo de las operaciones cotidianas. Existen varias dificultades a la hora de aplicar la ley en los casos de pornografía infantil y procesar a los autores de este delito a través de los métodos tradicionales de investigación, es por esto que a lo largo del presente trabajo analizaremos aquellos problemas y a modo de propuesta determinaremos si es posible aplicar nuevos métodos de investigación como el agente encubierto cibernético o el allanamiento virtual para dar una respuesta efectiva a esta clase de delitos. Con la entrada en vigencia del Código Orgánico Integral Penal se dio un avance significativo en la tipificación del delito de pornografía infantil, y se incluyeron novedosas vías de investigación; no obstante, la carencia de instrumentos tecnológicos, la falta de planes de investigación consensuados, escasez de capacitación especializada, dificultades en la cooperación internacional y fundamentalmente la resistencia a la innovación, son circunstancias que dificultan su aplicación. El avance legislativo que enfrentan los países desarrollados sobre la temática, ha permitido generar un instrumento guía para el manejo judicial de los delitos generados por las nuevas tecnologías; en particular, el Convenio de Ciberdelincuencia (Budapest), contempla preceptos sustantivos y procesales para un adecuado manejo del delito de pornografía infantil; si bien es cierto ha sido desarrollado en el margen de la Unión Europea, su contenido rebasa las instancias nacionales, propias de los delitos transnacionales, instrumento que puede ser tomado en cuenta para establecer regulaciones sobre la materia en nuestra región.

Tratamiento tributario para los organismos no gubernamentales de acuerdo a la normativa vigente

Las ONGs tienen diversidad de campos de acción en el ámbito social, están creados bajo el Código Civil; muchas de ellas son ejecutoras de Convenios Internacionales, los que mantienen una jerarquía legal superior, sin embargo los fondos que se manejan deben cumplir tanto los requisitos internacionales suscritos en el Convenio como los locales. En el ámbito tributario, no existe un documento que compile de forma clara el tratamiento tributario, las obligaciones que deben cumplir, así como los deberes formales a los que están sometidos para mantener las exenciones a las que tiene derecho de acuerdo a la normativa vigente El objetivo del presente trabajo es ofrecer una herramienta de consulta tributaria y contable sobre el tratamiento tributario, los deberes formales y las obligaciones tributarias adecuada a las características de los Organismos No Gubernamentales ONGs, de manera que permita cumplir a cabalidad la Ley Tributaria vigente, durante la ejecución de los proyectos o convenios internacionales, con el objeto de potenciar la eficiencia administrativa, contable y económica específicamente y de su relación con las operaciones del proyecto para incrementar su impacto social en el país. Con base en el régimen jurídico vigente, Ley de Régimen Tributario Interno y su Reglamento, Convenios Internacionales y Normativa internacional sobre pago de impuestos con fondos de asistencia, se trata: en el primer capítulo sobre las ONGs su creación y control así como sobre los convenios internacionales; en el segundo capítulo constan los deberes formales y obligaciones tributarias a cumplir, en cada impuesto se detallan sus generalidades, deberes formales, retenciones y comportamiento contable; en el tercer capítulo constan las obligaciones tributarias seccionales, los impuestos y su normativa de exención; finalmente en el cuarto capítulo a manera de conclusiones se presenta la realidad tributaria internacional comparada para organizaciones no gubernamentales.

Concepto, alcance y tratamiento de canon y regalía en la legislación de los Estados miembros de la Comunidad Andina

La consideración de bienes intangibles como generadores de regalías es un tema importante dentro de la fiscalidad internacional, mas aún si estamos en una realidad en la que el surgimiento de transacciones sobre tecnología, comercio electrónico, software, intercambio de bienes y servicios, y otros son considerados fundamentales dentro del comercio internacional y la correspondiente aplicación de normativa tributaria. Sin embargo este tipo de rentas conlleva en esencia la característica de ser muy compleja y de complicado tratamiento, abarcando una gran variedad de bienes y servicios como son los derechos de propiedad intelectual, propiedad industrial y know-how. Estos problemas se presentan al ser erróneamente categorizadas con otros tipos de renta siendo esto un cuello de botella para la pertinente calificación impositiva que recae sobre ellas. Con esta investigación se expone cual es el tratamiento que reciben estas rentas, bajo un enfoque dogmático conformado por las distintas posiciones doctrinarias, la consideración que merecen en el ámbito internacional y supranacional, los diferentes instrumentos que conforman el ámbito donde se desarrollan como los modelos de convenio, convenios para evitar la doble imposición, y posteriormente ver cual es el tratamiento normativo que brindan los estados miembros de la CAN con sus legislaciones internas. Culminada la presente investigación el resultado mostrará si es o no coincidente la regulación interna de los países miembros con lo señalado por la doctrina y la práctica internacional.

Ex Vivo Construction of an Artificial Ocular Surface by Combination of Corneal Limbal Epithelial Cells and a Compressed Collagen Scaffold Containing Keratocytes

We have investigated the use of a laminin coated compressed collagen gel containing corneal fibroblasts (keratocytes) as a novel scaffold to support the growth of corneal limbal epithelial stem cells. The growth of limbal epithelial cells was compared between compressed collagen gel and a clinically proven conventional substrate, denuded amniotic membrane. Following compression of the collagen gel, encapsulated keratocytes remained viable and scanning electron microscopy showed that fibres within the compressed gel were dense, homogeneous and similar in structure to those within denuded amniotic membrane. Limbal epithelial cells were successfully expanded upon the compressed collagen resulting in stratified layers of cells containing desmosome and hemidesmosome structures. The resulting corneal constructs of both the groups shared a high degree of transparency, cell morphology and cell stratification. Similar protein expression profiles for cytokeratin 3 and cytokeratin 14 and no significant difference in cytokeratin 12 mRNA expression levels by real time PCR were also observed. This study provides the first line of evidence that a laminin coated compressed collagen gel containing keratocytes can adequately support limbal epithelial cell expansion, stratification and differentiation to a degree that is comparable to the leading conventional scaffold, denuded amniotic membrane.

A role for Notch signaling in human corneal epithelial cell differentiation and proliferation

PURPOSE. To identify the role of Notch signaling in the human corneal epithelium. METHODS. Localization of Notch1, Notch2, Delta1, and Jagged1 in the human corneal epithelium was observed with the use of indirect immunofluorescence microscopy. Gene and protein expression of Notch receptors and ligands in human corneal epithelial cells was determined by RT-PCR and Western blot analysis, respectively. The effects of Notch inhibition (by {gamma}-secretase inhibition) and activation (by recombinant Jagged1) on epithelial cell proliferation (Ki67) and differentiation (CK3) were analyzed after Western blotting and immunocytochemistry. RESULTS. Immunofluorescent labeling localized Notch1 and Notch2 to suprabasal epithelial cell layers, whereas Delta1 and Jagged1 were observed throughout the corneal epithelium. Notch1, Notch2, Delta1, and Jagged1 genes and proteins were expressed in human corneal epithelial cells. {gamma}-Secretase inhibition resulted in decreased Notch1 and Notch2 expression, with an accompanying decrease in Ki67 and increased CK3 expression. The activation of Notch by Jagged1 resulted in the upregulation of active forms of Notch1 and 2 proteins (P < 0.05), with a concurrent increase in Ki67 (P < 0.05) and a decrease in CK3 (P < 0.05) expression. Interestingly, {gamma}-secretase inhibition in a three-dimensional, stratified corneal epithelium equivalent had no effect on Ki67 or CK3 expression. In contrast, Jagged1 activation resulted in decreased CK3 expression (P < 0.05), though neither Notch activation nor inhibition affected cell proliferation in the 3D tissue equivalent. CONCLUSIONS. Notch family members and ligands are expressed in the human corneal epithelium and appear to play pivotal roles in corneal epithelial cell differentiation.

Photochemical cross-linking of plastically compressed collagen gel produces an optimal scaffold for corneal tissue engineering

The experiments were designed to use photochemically cross-linked plastically compressed collagen (PCPCC) gel to support corneal epithelial cells. A plastically compressed collagen (PCC) scaffold was photo cross-linked by UVA in the presence of riboflavin to form a biomaterial with optimal mechanical properties. The breaking force, rheology, surgical suture strength, transparency, ultrastructure, and cell-based biocompatibility were compared between PCPCC and PCC gels. The breaking force increased proportionally with an increased concentration of riboflavin. The stress required to reach breaking point of the PCPCC scaffolds was over two times higher compared to the stress necessary to break PCC scaffolds in the presence of 0.1% riboflavin. Rheology results indicated that the structural properties of PCC remain unaltered after UVA cross-linking. The PCC gels were more easily broken than PCPCC gels when sutured on to bovine corneas. The optical density values of PCPCC and PCC showed no significant differences (p > 0.05). SEM analyses showed that the collagen fibres within the PCPCC gels were similar in morphology to PCC gels. No difference in cell-based biocompatibility was seen between the PCPCC and PCC scaffolds in terms of their ability to support the ex vivo expansion of corneal epithelial cells or their subsequent differentiation evidenced by similar levels of cytokeratin 14. In conclusion, PCPCC scaffold is an optimal biomaterial for use in therapeutic tissue engineering of the cornea.

Enhanced viability of corneal epithelial cells for efficient transport/storage using a structurally-modified calcium alginate hydrogel

Aims: Therapeutic limbal epithelial stem cells could be managed more efficiently if clinically validated batches were transported for ‘on-demand’ use. Materials & methods: In this study, corneal epithelial cell viability in calcium alginate hydrogels was examined under cell culture, ambient and chilled conditions for up to 7 days. Results: Cell viability improved as gel internal pore size increased, and was further enhanced with modification of the gel from a mass to a thin disc. Ambient storage conditions were optimal for supporting cell viability in gel discs. Cell viability in gel discs was significantly enhanced with increases in pore size mediated by hydroxyethyl cellulose. Conclusion: Our novel methodology of controlling alginate gel shape and pore size together provides a more practical and economical alternative to established corneal tissue/cell storage methods.

Influence of substrate on corneal epithelial cell viability within ocular surface models

Corneal tissue engineering has improved dramatically over recent years. It is now possible to apply these technological advancements to the development of superior in vitro ocular surface models to reduce animal testing. We aim to show the effect different substrates can have on the viability of expanded corneal epithelial cells and that those which more accurately mimic the stromal surface provide the most protection against toxic assault. Compressed collagen gel as a substrate for the expansion of a human epithelial cell line was compared against two well-known substrates for modeling the ocular surface (polycarbonate membrane and conventional collagen gel). Cells were expanded over 10 days at which point cell stratification, cell number and expression of junctional proteins were assessed by electron microscopy, immunohistochemistry and RT-PCR. The effect of increasing concentrations of sodium lauryl sulphate on epithelial cell viability was quantified by MTT assay. Results showed improvement in terms of stratification, cell number and tight junction expression in human epithelial cells expanded upon either the polycarbonate membrane or compressed collagen gel when compared to a the use of a conventional collagen gel. However, cell viability was significantly higher in cells expanded upon the compressed collagen gel. We conclude that the more naturalistic composition and mechanical properties of compressed collagen gels produces a more robust corneal model.

Cyclodextrin-mediated enhancement of riboflavin solubility and corneal permeability

Cyclodextrins are water-soluble cyclic oligosaccharides consisting of six, seven, and eight α-(1,4)-linked glucopyranose subunits. This study reports the use of different cyclodextrins in eye drop formulations to improve the aqueous solubility and corneal permeability of riboflavin. Riboflavin is a poorly soluble drug with a solubility up to 0.08 mg mL–1 in deionized water. It is used as a drug topically administered to the eye to mediate UV-induced corneal cross-linking in the treatment of keratoconus. Aqueous solutions of β-cyclodextrin (10–30 mg mL–1) can enhance the solubility of riboflavin up to 0.12–0.19 mg mL–1, whereas the higher concentration of α-cyclodextrin (100 mg mL–1) achieved a lower level of enhancement of 0.11 mg mL–1. The other oligosaccharides were found to be inefficient for this purpose. In vitro diffusion experiments performed with fresh and cryopreserved bovine cornea have demonstrated that β-cyclodextrin enhances riboflavin permeability. The mechanism of this enhancement was examined through microscopic histological analysis of the cornea and is discussed in this paper.

Oxidized alginate hydrogels as niche environments for corneal epithelial cells

Chemical and biochemical modification of hydrogels is one strategy to create physiological constructs that maintain cell function. The aim of this study was to apply oxidised alginate hydrogels as a basis for development of a biomimetic niche for limbal epithelial stem cells that may be applied to treating corneal dysfunction. The stem phenotype of bovine limbal epithelial cells (LEC) and the viability of corneal epithelial cells (CEC) were examined in oxidised alginate gels containing collagen IV over a 3-day culture period. Oxidation increased cell viability (P - 0.8 microm) than unmodified gels (pore diameter: 0.05 - 0.1 microm) and were significantly less stiff (P corneal extracellular matrix proteins can influence corneal epithelial cell function in a manner that may impact beneficially on corneal wound healing therapy.

The secretome of alginate-encapsulated limbal epithelial stem cells modulates corneal epithelial cell proliferation

Limbal epithelial stem cells may ameliorate limbal stem cell deficiency through secretion of therapeutic proteins, delivered to the cornea in a controlled manner using hydrogels. In the present study the secretome of alginate-encapsulated limbal epithelial stem cells is investigated. Conditioned medium was generated from limbal epithelial stem cells encapsulated in 1.2% (w/v) calcium alginate gels. Conditioned medium proteins separated by 1-D gel electrophoresis were visualized by silver staining. Proteins of interest including secreted protein acidic and rich in cysteine, profilin-1, and galectin-1 were identified by immunoblotting. The effect of conditioned medium (from alginate-encapsulated limbal epithelial stem cells) on corneal epithelial cell proliferation was quantified and shown to significantly inhibit (Pcorneal epithelial cell proliferation. We conclude that limbal epithelial stem cells encapsulated in alginate gels may regulate corneal epithelialisation through secretion of inhibitory proteins.

In vivo study of the biocompatibility of a novel compressed collagen hydrogel scaffold for artificial corneas

The experiments were designed to evaluate the biocompatibility of a plastically compressed collagen scaffold (PCCS). The ultrastructure of the PCCS was observed via scanning electron microscopy. Twenty New Zealand white rabbits were randomly divided into experimental and control groups that received corneal pocket transplantation with PCCS and an amniotic membrane, respectively. And the contralateral eye of the implanted rabbit served as the normal group. On the 1st, 7th, 14th, 21st, 30th, 60th, 90th, and 120th postoperative day, the eyes were observed via a slit lamp. On the 120th postoperative day, the rabbit eyes were enucleated to examine the tissue compatibility of the implanted stroma. The PCCS was white and translucent. The scanning electron microscopy results showed that fibers within the PCCS were densely packed and evenly arranged. No edema, inflammation, or neovascularization was observed on ocular surface under a slit lamp and few lymphocytes were observed in the stroma of rabbit cornea after histological study. In conclusion, the PCCS has extremely high biocompatibility and is a promising corneal scaffold for an artificial cornea. (c) 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.

The effects of retinoic acid on human corneal stromal keratocytes cultured in vitro under serum-free conditions

Purpose: Retinoic acid (RA) is a metabolite of vitamin A that plays a fundamental role in the development and function of the human eye. The purpose of this study was to investigate the effects of RA on the phenotype of corneal stromal keratocytes maintained in vitro for extended periods under serum-free conditions. Methods: Keratocytes isolated from human corneas were cultured up to 21 days in serum-free media supplemented with RA or DMSO vehicle. The effects of RA and of its removal after treatment on cell proliferation and morphology were evaluated. In addition, the expression of keratocyte markers was quantified at the transcriptional and protein levels by quantitative PCR and immunoblotting or ELISA, respectively. Furthermore, the effects of RA on keratocyte migration were tested using scratch assays. Results: Keratocytes cultured with RA up to 10×10-6 M showed enhanced proliferation and stratification, and reduced mobility. RA also promoted the expression of keratocyte-characteristic proteoglycans such as keratocan, lumican, and decorin, and increased the amounts of collagen type-I in culture while significantly reducing the expression of matrix metalloproteases 1, 3, and 9. RA effects were reversible, and cell phenotype reverted to that of control after removal of RA from media. Conclusions: RA was shown to control the phenotype of human corneal keratocytes cultured in vitro by regulating cell behaviour and extracellular matrix composition. These findings contribute to our understanding of corneal stromal biology in health and disease, and may prove useful in optimizing keratocyte cultures for applications in tissue engineering, cell biology, and medicine.