History, Philosophy and Theory of the Life Sciences
Unlike inert objects, organisms and their cells have the ability to initiate activity by themselv... more Unlike inert objects, organisms and their cells have the ability to initiate activity by themselves and thus change their properties or states even in the absence of an external cause. This crucial difference led us to search for principles suitable for the study organisms. We propose that cells follow the default state of proliferation with variation and motility, a principle of biological inertia. This means that in the presence of sufficient nutrients, cells will express their default state. We also propose a principle of variation that addresses two central features of organisms, variation and historicity. To address interdependence between parts, we use a third principle, the principle of organization, more specifically, the notion of the closure of constraints. Within this theoretical framework, constraints are specific theoretical entities defined by their relative stability with respect to the processes they constrain. Constraints are mutually dependent in an organized syste...
Les organismes, qu'ils soient uni ou multi-cellulaires, sont des agents capables de créer leurs p... more Les organismes, qu'ils soient uni ou multi-cellulaires, sont des agents capables de créer leurs propres normes ; ils articulent continuellement leur capacité à créer de la nouveauté et de la stabilité, c'est-à-dire qu'ils combinent plasticité et robustesse. Ici, nous présentons et articulons brièvement les trois principes proposés récemment pour une théorie des organismes, à savoir : l'état par défaut, prolifération avec variation et motilité, le principe de variation et le principe d'organisation. Ces principes modifient profondément les observables biologiques et leur nature théorique par rapport aux cadres des théories physiques. Ce changement radical ouvre la possibilité d'ancrer la modélisation mathématique à des principes proprement biologiques. ABSTRACT. Organisms, whether uni or multi-cellular, are agents that make their own norms; they continually express their ability to generate novelty and stability, that is to say they combine plasticity and robustness. Here, we briefly present and describe the three main principles that our group proposes for a theory of organisms, namely: the default state, proliferation with variation and motility, the principle of variation and the principle of organization. These principles profoundly modify biological observables and their theoretical nature compared to the situation in physical theories. This radical change opens up the possibility of anchoring mathematical modeling to biological principles.
We commend Dan Sarewi , a professor of Science and Society at Arizona State University, for his r... more We commend Dan Sarewi , a professor of Science and Society at Arizona State University, for his recent arti - cle on the status of science (Sarewitz, 2016). The article sheds light on the complex issue of irreproducibility and lack of progress in certain areas of scienti c re - search, particularly on the sociological determinants of the status quo . These are compelling explanations and therefore will not be addressed in our commentary. We will posit, instead, that contrary to Sarewi’ opinion, the notion that progress in fundamental science cannot be managed from “outside” by managers focused on speci c practical results, or contrary to the current NIH practice, from “inside” by “study sections” populated by peers that while accepting the current dogma, may be incapable or unwilling to recognize a novel idea and, thus, intent to maintain the status quo (Huang, 2013).
Endocrinologists apply the idea of feedback loops to explain how hormones regulate certain bodily... more Endocrinologists apply the idea of feedback loops to explain how hormones regulate certain bodily functions such as glucose metabolism. In particular, feedback loops focus on the maintenance of the plasma concentrations of glucose within a narrow range. Here, we put forward a different, organicist perspective on the endocrine regulation of glycaemia, by relying on the pivotal concept of closure of constraints. From this perspective, biological systems are understood as organized ones, which means that they are constituted of a set of mutually dependent functional structures acting as constraints, whose maintenance depends on their reciprocal interactions. Closure refers specifically to the mutual dependence among functional constraints in an organism. We show that, when compared to feedback loops, organizational closure can generate much richer descriptions of the processes and constraints at play in the metabolism and regulation of glycaemia, by making explicit the different hierarchical orders involved. We expect that the proposed theoretical framework will open the way to the construction of original mathematical models, which would provide a better understanding of endocrine regulation from an organicist perspective.
BackgroundCLARITY-BPA is a rare collaboration of guideline-compliant (core) studies and academic ... more BackgroundCLARITY-BPA is a rare collaboration of guideline-compliant (core) studies and academic hypothesis-based studies to assess the effects of bisphenol A (BPA).Objectives1) determine BPA’s effects on the developing rat mammary gland using new quantitative and established semi-quantitative methods in two labs, 2) develop a software tool for semi-automatic evaluation of quantifiable aspects of the mammary ductal tree, and 3) compare those methods.MethodsSprague Dawley rats were exposed to BPA, vehicle, or positive control (ethinyl estradiol, EE2) by oral gavage beginning on gestational day 6 and continuing with direct dosing of the pups after birth. There were two studies; sub-chronic and chronic. The latter used two exposure regimes, one stopping at PND21 the other continuing until tissue harvest. Glands were harvested at multiple time points; whole mounts and histological specimens were analyzed blinded to treatment.ResultsThe subchronic study’s semiquantitative analysis reveal...
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Papers by Ana M Soto