Receptor oligomerization plays a key role in maintaining genome stability and restricting protein mutagenesis. When properly folded, protein monomers assemble as oligomeric receptors and interact with environmental ligands. In a gene-centered view, the ligand specificity expressed by these receptors is assumed to be causally predetermined by the cell genome. However, this mechanism does not fully explain how differentiated cells have come to express specific receptor repertoires and which combinatorial codes have been explored to activate their associated signaling pathways. It is (...) our contention that the plasma membrane acts as the locus where several contextual cues may be integrated. As such it allows the semiotic selection of those receptor configurations that provide cells with the minimum essential requirements for agency. The occurrence of protein misfolding makes it impossible for receptor monomers to assemble along the membrane and to sustain meaningful relationships with environmental ligands. How could a cell lineage deal with these loss-of-function mutations during evolution and restrain gene redundancy accordingly? In this paper, we will be arguing that the easiest way for bacteria clones to accomplish this goal is by getting rid of cells expressing mutated receptor proteins. The mechanism sustaining this cell selection is also occurring in many somatic tissues and its function is currently believed to counteract in vivo protein mutagenesis. Our discussion will be mainly focused on the significance and semiotic nature of the interplay between membrane receptors and the epigenetic control of gene expression, as mediated by the control of mismatched repairing and protein folding mechanisms. (shrink)

Established at the annual meeting of the International Society for Biosemiotic Studies on July 3rd 2014, in conjunction with Springer Publishing, publishers of the Society’s official journal, Biosemiotics, the Annual Biosemiotic Achievement Award seeks to recognize those papers published in the journal that present novel and potentially important contributions to the ongoing project of biosemiotic research, its scientific impact, and its future prospects. Here the winner of the Biosemiotics Achievement Award for 2019 is announced: the award goes to Y.H. Hendlin (...) for the article ‘I Am a Fake Loop: the Effects of Advertising-Based Artificial Selection’. (shrink)

The concept of scaffolding has wide resonance in several scientific fields. Here we attempt to adopt it for the study of development. In this perspective, the embryo is conceived as an integral whole, comprised of several hierarchical modules as in a recurrent circularity of emerging patterns. Within the developmental hierarchy, each module yields an inter-level relationship that makes it possible for the scaffolding to mediate the production of selectable variations. A wide range of genetic, cellular and morphological mechanisms allows the (...) scaffolding to integrate these modular variations into a functionally coordinate unit. A genetic scaffolding accounts for the inherited invariance of pattern formation during the embryo’s growth. At higher level, cells behave as agents endowed with the capacity to interpret any scaffolding variation as signs. The full hierarchy of a multi-level scaffolding is eventually attained when the embryo acquires the capacity to impose a number of developmental constraints on its constituting parts in a top-down direction. The acquisition of this capacity allows a semiotic threshold to emerge between the living cellular world and the underlying non-living molecular world. As this boundary is gradually defined during development, cells enter into new functional relationships, while, at the same time, are relieved from their physical determinism. The resulting constraints can thus become the driving forces that upgrade embryonic scaffolding from the simple molecular signalling to the complexity of sign recognition proper of a cellular community. In this semiotic perspective, the apparent goal directness of any developmental strategy should no longer be accounted for by a predetermined genetic program, but by the gradual definition of the relationships selected amongst the ones historically explored. (shrink)

: The technologies at the intersection of assisted reproduction and genetics call for a new regulatory approach, say Franco Furger and Francis Fukuyama, authors of the recent report Beyond Bioethics. In the essay below they map out their recommendation. In the following essays, James Fossett argues that regulation is likelier—and would be better—at the state level, Leonard Fleck calls for more robust public involvement, and John Robertson recommends sticking with the status quo. Turning from procedural to substantive issues, Josephine (...) Johnston takes up Furger and Fukuyama’s suggestion that children have a right to a traditional genetic parentage. (shrink)

The majority of G protein-coupled receptors (GPCRs) self-assemble in the form dimeric/oligomeric complexes along the plasma membrane. Due to the molecular interactions they participate, GPCRs can potentially provide the framework for discriminating a wide variety of intercellular signals, as based on some kind of combinatorial receptor codes. GPCRs can in fact transduce signals from the external milieu by modifying the activity of such intracellular proteins as adenylyl cyclases, phospholipases and ion channels via interactions with specific G-proteins. However, in spite of (...) the number of cell functions they can actually control, both GPCRs and their associated signal transduction pathways are extremely well conserved, for only a few alleles with null or minor functional alterations have so far been found. This would seem to suggest that, beside a mechanism for DNA repairing, there must be another level of quality control that may help maintaining GPCRs rather stable throughout evolution. We propose here receptor oligomerization to be a basic molecular mechanism controlling GPCRs redundancy in many different cell types, and the plasma membrane as the first hierarchical cell structure at which selective categorical sensing may occur. Categorical sensing can be seen as the cellular capacity for identifying and ordering complex patterns of mixed signals out of a contextual matrix, i.e., the recognition of meaningful patterns out of ubiquitous signals. In this context, redundancy and degeneracy may appear as the required feature to integrate the cell system into functional units of progressively higher hierarchical levels. (shrink)

Cell communication plays a key role in multicellular organisms. In developing embryos as in adult organisms, cells communicate by coordinating their differentiation through the establishment and/or renewal of a variety of cell communication channels. Under both these conditions, cells interact by either receptor signalling, surface recognition of specific cell adhesion molecules or transfer of cytoplasmic components through junctional coupling. In recent years, it has become apparent that cells may also communicate through the extracellular release of microvesicles. They may originate as (...) either exosomes from the endosomal compartment upon fusion of multivesicular bodies with the plasma membrane or be shed directly from the plasma membrane via extensions of the cell surface. Microvesicles may disperse over long distances through body fluids and deliver their molecular cargo onto a variety of target cells. As a general rule, the metabolic fate of these cells is determined by the molecular nature of the vesicular cargo, while targeting itself depends on the affinity of the molecules expressed on the enclosing membrane. In this paper, we will be arguing that intercellular vesicular transfer is substantially different from other types of cell communication, allowing cells and molecules to interact on varying levels. Cells interacting via ligand signalling owe their specificity to the steric coupling with cognate receptor molecules. As such, it is a pure molecular process that affects target cells only upon integration into their responding repertoire. In this relationship, coupled cells are reciprocally adapted to each other through the selection of their respective signalling capacities, following exploration of their receptor specificity. Interaction by intercellular vesicles realizes a substantially different type of cell communication. Vesicular traffic allows donor cells to carry out a horizontal type of gene transfer and target this information over long distances via independently controlled mechanisms. Because of this independence, cells interacting via vesicular traffic are not expected to adapt their signalling correspondences, but to control instead the efficiency of their cargo delivery irrespective of the receptor repertoire expressed by the target tissue. In this paper, the multifaceted functions of the intercellular vesicular traffic will be discussed in a multilevel biosemiotic perspective with the aim of unravelling the cellular mechanisms devised by nature to accomplish communication. (shrink)

v. 1. O direito como ciência (epistemologia jurídica). O direito como justo (axiologia jurídica).

Este trabajo intenta analizar la concepción, naturaleza jurídica y garantía de los derechos económicos, sociales y culturales, en América Latina, así como las condiciones y medidas que pueden contribuir a su efectividad. Presenta también una propuesta de indicadores que pueden utilizarse en la supervisión de la efectividad de esos derechos y de la protección que ellos han alcanzado, proporcionando información sobre la situación latinoamericana y caribeña actual.

A recent trend in bioethics has highlighted the decisive role that solidarity plays in global health. However, given the impact and extent of the effects of climate change, which reach beyond present generations, it is important to consider whether this concept can be applied intergenerationally. Does it make sense to talk about solidarity with future generations? The objective of this article is to explore ‘amplified solidarity’, a new concept of solidarity that explains our obligations towards the health and quality of (...) life of future generations. The analysis of this concept is structured as follows: I first establish the moral relevance of future people and then investigate the traits of amplified solidarity, its challenges, and its relationship with other key principles. I propose that amplified solidarity needs both a critical imagination to be projected towards the future and an institutional framework to correct health injustices across an intergenerational timescale. Solidarity forms a potent triangular constellation with responsibility and justice to fight against global and intergenerational injustices. (shrink)

In this paper we give a strong normalization proof for a set of reduction rules for classical logic. These reductions, more general than the ones usually considered in literature, are inspired to the reductions of Felleisen's lambda calculus with continuations.

Estudio bibliográfico de: / A Bibliographical Study of: G. Coccoli, C. Marrone, F. Ratto, G. Santese , Natura e storia. Saggi di filosofia, Edizioni Sestante, Ripatransone 1996, pp. 325.

The biopsychosocial model was initially proposed to overcome the normative assumption that human diseases are exclusively due to disordered biochemical and/or neurophysiological processes. The model attempts to explain how expectations, thoughts and feelings modify the patient’s motivations to deal with illness and recovery. By considering the physical health in this perspective, healthcare professionals may test the importance of socially and culturally shared principles in alleviating illness experience. The entire biopsychosocial hierarchy may thus appear as a complex network of relationships between (...) the strict logic of scientific explanations and the emotional sustainability with which beliefs may either be defended, changed or even refused. In this paper, we aim at reviewing some of the evidence-based biomedical and psychological findings that provide a unified framework for the biopsychosocial model as a multilevel integrative process. To tackle this objective, we propose to approach the model in biosemiotic terms. It is our contention that the entire biopsychosocial hierarchy could be better understood if approached biosemiotically and the multilevel interconnection of this hierarchy re-examined in the light of a collaborative meaning-making process. (shrink)

Germ cells are cross-roads of development and evolution. They define the origin of every new generation and, at the same time, represent the biological end-product of any mature organism. Germ cells are endowed with the following capacities: to store a self-descriptive program, to accumulate a protein-synthesizing machinery, and to incorporate enough nourishment to sustain embryonic development. To accomplish this goal, germ cells do not simply unfold a pre-determined program or realize a sole instructive role. On the contrary, due to the (...) complexity of their cytoarchitecture and the nature of the soma-to-germ interactions, they are heavily involved in processes of sign recognition and meaningful tissue exploration. At each stage of their inward migration, germ plasma membranes act as semiotic interfaces allowing cells to interact with the surrounding extracellular milieu and experience the compatibility of selected developmental sequences. The question of which signaling pathways are activated at each developmental stage does not result from a strictly predetermined program instructing germ cell stemness. Rather, each developmental sequence is an open-ended semiotic relationship explored and gradually defined during evolution by the context-dependency of specific cell-to-cell interactions. In this way, any structural and functional novelty that has emerged in the course of germ cell interactions may be interpreted as an exaptation fixed in the species genome in response to specific environmental constraints. (shrink)

The egg behaves as a prospective cell sustaining the developmental processes of the future embryo. In biosemiotic terms, this apparent teleonomic behaviour can be accounted for without referring to the exclusive causal role played by its genetic makeup. We envision two different processes that are uniquely found in the oocyte: (1) the first involves the mechanisms by which large amounts of mRNA accumulate in the ooplasm to establish the embryo axes prior to fertilization; (2) the second involves transfer of an (...) excess of maternally supplied ribosomes to the oocyte to provide the future embryo with newly synthesized proteins. In this paper, we argue that the information required to sustain embryonic development is not due to any physical properties of the zygotic DNA and the maternal mRNAs, but to their spatially and temporally ordered relationship in the zygote’s internal space. (shrink)

Book review of Marie Boas Hall, Henry Oldenburg: Shaping the Royal Society (Oxford: Oxford University Press, 2002), pp. xii + 369.

Una raccolta di testi che consente un primo approccio diretto alla varietà e ricchezza del pensiero femminista. Temi e figure principali vengono presentati seguendo un itinerario storicotematico e suddivisi per aree culturali, tenendo conto degli specifici contributi teorici delle singole aree: denuncia del patriarcalismo, dicotomia, sesso-genere, lesbofemminismo e femminismo etnico negli Stati Uniti; femminismo socialista integrato dalla psicoanalisi in Gran Bretagna; teoria della differenza sessuale e scrittura femminile in Francia; differenza e pensiero sessuato in Italia."--Page 4 of cover.

This volume makes an important contribution to the understanding of Greek Neoplatonism and its historical significance.

Quine is one of the most influential of contemporary philosophers, whose work has ranged broadly across a great number of topics and issues in a career spanning some fifty years. In this collection a group of distinguished philosophers offer a sustained critical evaluation of the full range of Quine's writings. Amongst the topics addressed are interpretation, epistemology, ontology, modality, and mathematical truth. This collection will certainly influence all future discussion of Quine. The contributors include: George Boolos, H-N. Castaneda, Donald Davidson, (...) Umberto Eco, Dagfinn Follesdal, James Higginbotham, Charles Parsons, Hilary Putnam, Barry Stroud, and Bas van Fraassen. However, Quine is given the last word, responding to the essays in the final contribution. (shrink)

Can psychology contribute in some way to the approach to the fundamental questions of life? Psychology can be and indeed often is seen and used as a technique. In reality, every psychology carries in itself the seeds, more or less developed, of an anthropology, just as every anthropology cannot but have a pedagogical/psychological component. Without claiming to be comprehensive, the article raises some questions concerning the unavoidable integration of psychological aspects with the fundamental dimensions of being, such as the truth (...) to be known, the good to be worked for, and the unity or harmony found at the basis of human motivations. All this cannot disregard the pedagogical dimension/mission, recalling that the question is not 'what' or 'if' but rather 'which one' and 'how'. (shrink)