Infecciones y alteraciones epigenéticas en cáncer

ResumenLa participación de mecanismos epigenéticos, junto con infecciones en etapas tempranas de la vida, moldean lesiones premalignas del cáncer, en particular el cáncer gástrico, uno de los tumores más frecuentes en Chile, Latinoamérica y el mundo. El principal objetivo de este artículo, como parte de la serie de revisiones en torno a mecanismos epigenéticos en el desarrollo de enfermedades crónicas, es actualizar el rol de alteraciones epigenéticas (i.e. metilación del ADN) en el contexto de la infección crónica por H. pylori en las etapas precursoras del cáncer gástrico. Las investigaciones desarrolladas en esta área permiten delinear desafíos e interrogantes, en los cuales la pediatría tiene un papel preponderante en el desarrollo de estrategias de prevención y detección temprana de esta enfermedad.AbstractThe role of epigenetics and infectious diseases at early stages of life influence pre-malignant lesions of cancer, in particular, gastric cancer, one of the most frequent tumours in Chile, Latin America, and worldwide. This article examines the role of H.pylori and epigenetic alterations (i.e. DNA methylation) at early stages of gastric cancer and proposes, from the paediatric point of view, strategies for prevention and early detection

Strong arsenic enrichment in sediments from the Elqui watershed, Northern Chile: industrial (gold mining at El Indio–Tambo district) vs. geologic processes.

Sediments from the Elqui watershed river system (9800 km2; northern Chile) are highly enriched in arsenic. The river system initiates in the high altitude domain of the Andes (3500–4000 m) and drains important hydrothermal alteration zones and epithermal deposits, including the copper-, and arsenic-rich gold veins of the well-known El Indio–Tambo district. In order to study the extent, source, and age of contamination, we carried out a geochemical survey of stream sediments and older, Early Holocene lacustrine sediments. The results reveal very high contents of arsenic in both, the stream (55–485 ppm As) and lacustrine sediments (119–2344 ppm As). As shown by the ESEM-EDX study, arsenic is associated with the iron oxide mineral phase. Given that arsenic is enriched in both the stream sediments and the Early Holocene sequence, we suggest that contamination is not only industrial derived (mining operations), but also a major geological process, related to long-lived erosion of the As-rich epithermal ores and alteration zones. Erosion in this realm is particularly important during El Niño years, when increased activity of the Westerly winds brings intense rains, with catastrophic consequences in the Elqui atershed, including the massive removal of sediments in the form of large debris flows.Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

Towards Autopoietic Computing

A key challenge in modern computing is to develop systems that address complex, dynamic problems in a scalable and efficient way, because the increasing complexity of software makes designing and maintaining efficient and flexible systems increasingly difficult. Biological systems are thought to possess robust, scalable processing paradigms that can automatically manage complex, dynamic problem spaces, possessing several properties that may be useful in computer systems. The biological properties of self-organisation, self-replication, self-management, and scalability are addressed in an interesting way by autopoiesis, a descriptive theory of the cell founded on the concept of a system's circular organisation to define its boundary with its environment. In this paper, therefore, we review the main concepts of autopoiesis and then discuss how they could be related to fundamental concepts and theories of computation. The paper is conceptual in nature and the emphasis is on the review of other people's work in this area as part of a longer-term strategy to develop a formal theory of autopoietic computing.Comment: 10 Pages, 3 figure

Self-organisation and psychotherapy

Neste artigo, resultado de uma pesquisa de tipo qualitativo, hermenêutico e documental, procuramos mostrar como as Ciências Cognitivas, desde a sua constituição, têm contribuído para a compreensão do ser humano. Fazemos referência às visões mais racionalistas da mente, que a entendem semelhante a um sistema computacional, até à visão menos (não) racionalista que lhe confere valor cognitivo, envolta em emoções e afetos, que numa visão mais construtivista – ou pós-racionalista – se diria que traduz significados, traduz uma vivência ou uma história narrativa (e) pessoal. Assim, apresentamos o modelo de terapia cognitiva pós-racionalista de Vittorio Guidano, refletindo sobre os fundamentos epistemológicos do Movimento da Auto-organização (MAO), nos quais ele se fundamenta. Descrevemos sumariamente os alicerces epistemológicos do MAO, os quais garantem a este modelo uma dimensão holista e explicativa do processo de construção da identidade humana, que pode ser descrita como processo de conhecimento, capaz de vivenciar e ao mesmo tempo perceber e avaliar a sua própria experiência (autoconsciência). O ser humano age na intersubjetividade, num mundo pluralista, com os seus congéneres, partilhando experiências e interpretando ações (complexificando-se através desses acoplamentos). Pretendemos, também, ilustrar que a matriz de funcionamento interno de cada ser humano, a qual lhe permite ordenar essa múltipla e facetada realidade, assim como formar/construir/ordenar significados pessoais, é o vínculo emotivo-afetivo.In this paper, which is the result of a qualitative, hermeneutical and documental research, we intend to show how the Cognitive Sciences, since their beginning, have contributed to the understanding of human beings. We refer to the rationalistic understanding of the mind (the mind is like a computer system), and also to the non-rationalistic understanding, which attributes to the mind a cognitive value, immersed in emotions and affections. In addition, according to a constructivist or post-rationalistic understanding, the mind translates meanings, an experience or a personal narrative story. Thus, we present the model of post-rationalistic cognitive therapy of Vittorio Guidano, reflecting on the epistemological foundations of the Self-Organization Movement, on which it is based. We describe briefly the epistemological principles of the Self-Organization Movement, which give to this model a holistic and explanatory dimension of the process of construction of human identity. This identity can be described as the human beings’ process of self-knowledge, as we are capable of experiencing and at the same time perceiving and evaluating, our own experiences (self-consciousness). The human being acts on intersubjectivity, in a pluralistic world with his peers, sharing experiences and interpreting actions. We also want to illustrate that the matrix of inner functioning of every human being, which allows us to sort this multi-faceted reality in a single personal order, is the emotional bond.(undefined

Antimicrobials in animal agriculture: Parables and policy

In addition to the scientific, economic, regulatory and other policy factors that impact on antimicrobial decision-making in different jurisdictions around the world, there exist ethical, social and cultural bases for the contemporary use of these products in animal agriculture. Thus, the use of the word ‘parable’ to describe the contemporary moral stories that help to guide ethical antimicrobial use practices and broader policy decisions in animal agriculture is appropriate. Several of these stories reflect difficult decisions that arise from conflicting moral imperatives (i.e. both towards animal welfare and towards human health). Understanding the factors that combine to define the past and present paradigms of antimicrobial usage is crucial to mapping a path forward. There exist barriers, as well as opportunities, for advancing scenarios for reducing antimicrobial usage under a variety of voluntary, regulatory and legal policy frameworks. Any new approaches will ideally be structured to extend the use of present-day antimicrobials into the future, to provide novel alternatives for regulating any newly introduced antimicrobial products so as to maximize their useful life span and to ensure the optimal use of these products in animal agriculture to protect not only the health of animals and the interests of animal health/agriculture stakeholders, but also the human health and the interests of the public at large. A full range of policy approaches, which span the realm from strictly enforced regulations and laws to voluntary guidelines and compliance, should be explored with respect to their risks and benefits in a variety of worldwide settings and in full consideration of a range of stakeholder values

Neurophysiology

Contains reports on seven research projects.Bell Telephone Laboratories, IncorporatedNational Institutes of HealthTeagle Foundation, IncorporatedUnited States Air Force (WADD Contract AF33(616)-7783

Performing the paradox: collaboration as intervention in Eis o Homem

After the economic crisis of 2008, Portugal, like other European countries, underwent a readjustment programme based on neo-liberal principles. This programme widened the gap between rich and poor and elevated the economic over the social, the political and the affective. This paper analyses the devised performance Eis o Homem (Behold Man) as both an artistic and intellectual intervention in this context of crisis. It suggests that collaboration between artists on an explicitly non-hierarchical basis functioned as a coping mechanism for both the artists involved and the audience. The material generated during rehearsals contrasted the powerful reality of life as lived by Portuguese citizens during this period with the Real, that, as Slavoj Zizek has argued, masked this reality with social discourses that emphasized that there was no alternative to the dominance of the market. It concludes that such forms of theatrical collaboration, which explicitly contemplate the right to dissensus, can lead to complex, transformative responses to social situations and to dialogically-informed performances