The human intestines are constantly under the influence of numerous pathological factors: enteropathogenic microorganisms, food antigens, physico‐chemical stress associated with digestion and bacterial metabolism, therefore it must be provided with a system of protection against adverse impact. Recent studies have shown that Paneth cells play a crucial role in maintaining homeostasis of the small intestines. Paneth cells perform many vital functions aimed at maintaining a homeostatic balance between normal microbiota, infectious pathogens and the human body, regulate (...) the qualitative composition and number of intestinal microorganisms, prevent the introduction of potentially pathogenic species, and protect stem cells from damage. Paneth cells take part in adaptive and protective‐inflammatory reactions. Paneth cells maintain dynamic balance between microbial populations, and the macroorganism, preventing the development of intestinal infections and cancer. They play a crucial role in gastrointestinal homeostasis and may be key factors in the etiopathological progression of intestinal diseases. (shrink)

This article is a translation into english of a lecture given by paneth in 1931. The content of the work is described by the section titles: (1) the need for epistemological clarification of the fundamental concepts of chemistry, (2) the concept of substance in chemistry, (3) the epistemological standpoint of the ancient atomists, (4) the epistemological position of the concept of element introduced by lavoisier, (5) the double meaning of the chemical concept of element: 'basic substance' and 'simple substance', (...) And (6) the double meaning of other chemical concepts. Sections (4)-(6) are published in the following number of this journal. (staff). (shrink)

This article is a translation into english of a lecture given by paneth in 1931. The content of the work is described by the section titles: (1) the need for epistemological clarification of the fundamental concepts of chemistry, (2) the concept of substance in chemistry, (3) the epistemological standpoint of the ancient atomists, (4) the epistemological position of the concept of element introduced by lavoisier, (5) the double meaning of the chemical concept of element: 'basic substance' and 'simple substance', (...) And (6) the double meaning of other chemical concepts. Sections (4)-(6) are published in the following number of this journal. (staff). (shrink)

This article is a translation into english of a lecture given by paneth in 1931. The content of the work is described by the section titles: (1) the need for epistemological clarification of the fundamental concepts of chemistry, (2) the concept of substance in chemistry, (3) the epistemological standpoint of the ancient atomists, (4) the epistemological position of the concept of element introduced by lavoisier, (5) the double meaning of the chemical concept of element: 'basic substance' and 'simple substance', (...) And (6) the double meaning of other chemical concepts. Sections (4)-(6) are published in the following number of this journal. (staff). (shrink)

The molecular genetic age can be said to have begun with the letter in Nature in 1953 by Watson and Crick, describing the helical structure of DNA. Some outstanding scientific work preceded that discovery, including especially the recognition by Chargaff of base-pair complementarity, but no discovery quite captured the imagination of the biomedical world as a few understated words by Watson and Crick in their famous one-page paper: "It has not escaped our notice that the specific pairing we have postulated (...) immediately suggests a possible copying mechanism for the genetic material". The manner in which genetic material was passed on from generation to generation had been decoded.That discovery was... (shrink)

Any human enterprise that consumes billions of dollars, especially when those dollars are those of citizen tax payers, should be subject to at least occasional scrutiny and stock-taking. This Special Issue of Perspectives in Biology and Medicine is an attempt to do just that: to ask whether the massive investment of money, equipment and human scientific talent that has been poured into studying the human genome under the assumption that this enormous scientific endeavor will advance human health has been worth (...) it thus far, and whether it is likely to bear fruit in the futureThe expression that best encapsulates the goal of using genomic information to alter trajectories of... (shrink)

Among emotions, surprise has been extensively studied in psychology. In linguistics, surprise, like other emotions, has mainly been studied through the syntactic patterns involving surprise lexemes. However, little has been done so far to correlate the reaction of surprise investigated in psychological approaches and the effects of surprise on language. This cross-disciplinary volume aims to bridge the gap between emotion, cognition and language by bringing together nine contributions on surprise from different backgrounds - psychology, human-agent interaction, linguistics. Using different methods (...) at different levels of analysis, all contributors concur in defining surprise as a cognitive operation and as a component of emotion rather than as a pure emotion. Surprise results from expectations not being met and is therefore related to epistemicity. Linguistically, there does not exist an unequivocal marker of surprise. Surprise may be either described by surprise lexemes, which are often associated with figurative language, or it may be expressed by grammatical and syntactic constructions. Originally published as a special issue of Review of Cognitive Linguistics 13:2 (2015). (shrink)

Nous étudions dans cet article les différentes formes de prédication seconde détachée en position initiale dans un corpus comparable composé de textes d’économie en anglais et en français. Ce corpus a été annoté sous le logiciel Analec. L’enjeu est de montrer en quoi un même phénomène syntaxique est exploité, sur le plan discursif, de façon divergente dans chacune des deux langues. Une étude qualitative et quantitative des prédications secondes du corpus montre que la prédication seconde prend le plus souvent la (...) forme d’une participiale en –ing en anglais, où elle se spécialise dans un rôle méta-énonciatif de balise textuelle pour le lecteur, ce qui n’est pas le cas en français. (shrink)

This study presents a sociological profile of Peruvian female industrialists and some narratives of their struggle for personal independence and entrepreneurial success within the context of global restructuring and local deindustrialization. The study adopts the classical definition of woman's economic independence as a result of women's participation in the world of paid labor.

Surprise is treated as an affect in Aristotelian philosophy as well as in Cartesian philosophy. In experimental psychology, surprise is considered to be an emotion. In phenomenology, it is only addressed indirectly (Husserl, Heidegger, Levinas), with the important exception of Ricoeur and Maldiney; it is reduced to a break in cognition by cognitivists (Dennett). Only recently was it broached in linguistics, with a focus on lexico-syntactic categories. As for the expression of surprise, it has been studied in connection with evidentiality (...) in languages that encode surprise morphosyntactically. However, how surprise is encoded in languages that lack an evidential morphosyntactic system has been largely unexplored. This book provides new insights into the dynamics of surprise based on a heuristic hypothesis tested against the investigation of time, language and emotion. It is intended to arouse the interest of a multidisciplinary audience keen on crossing the disciplinary borders of phenomenology, cognitive sciences, and pragmatics. The theoretical approaches adopted in this collection of articles rely on experiments and corpus data. They advance knowledge by building on robust empirical results coming from psychology, microphenomenology, linguistics and physiology. (shrink)

Friedrich Paneth’s conception of “chemical element” has functioned as the official definition adopted by the International Union of Pure and Applied Chemistry since 1923. Paneth maintains a distinction between empirical and “transcendental” concepts of element; furthermore, chemical science requires fluctuation between the two. The origin of the empirical-transcendental split is found in Immanuel Kant’s classic Critique of Pure Reason (1781/1787). The present paper examines Paneth’s foundational concept of element in light of Kant’s attempt, late in life, to (...) revoke key distinctions made in his Critique, including that of regulative and constitutive functions of reason. In a section of his Opus postumum devoted to the “Transition from the Metaphysical Foundations of Natural Science to Physics,” Kant bends his philosophical system to address the newly emerging sciences of matter of his time. Specifically, he tried, without success, to develop the transcendental ground for microscale motions of bodies encountered in physical, electrical and chemical processes. Paneth’s discussion of chemical element does not take the Opus postumum into account, which is why it begins with a rejection of Kant’s rejection (in his earlier writings) of chemistry’s status as science. I make the case that Paneth’s definition of element effectively maintains something very like Kant’s critical separation of regulative and constitutive principles, while a advancing the concept of chemical science. (shrink)

Immanuel Kant has built up a dualistic epistemology that seems to fit to the peculiarities of chemistry quite well. Friedrich Paneth used Kant’s concept and characterised simple and basic substances which refer to the empirical and to the transcendental world, respectively. This paper takes account of the Kantian influences in Paneth’s philosophy of chemistry, and discusses pertinent topics, like observables, atomism and realism.

Between 1940 and 1970 pioneers in the new field of cell biology discovered the operative parts of cells and their contributions to cell life. They offered mechanistic accounts that explained cellular phenomena by identifying the relevant parts of cells, the biochemical operations they performed, and the way in which these parts and operations were organised to accomplish important functions. Cell biology was a revolutionary science but in this book it also provides fuel for yet another revolution, one that (...) focuses on the very conception of science itself. Laws have traditionally been regarded as the primary vehicle of explanation, but in the emerging philosophy of science it is mechanisms that do the explanatory work. Bechtel emphasises how mechanisms were discovered, focusing especially on the way in which new instruments made these inquiries possible. He also describes how new journals and societies provided institutional structure to this new enterprise. (shrink)

Between 1940 and 1970 pioneers in the new field of cell biology discovered the operative parts of cells and their contributions to cell life. They offered mechanistic accounts that explained cellular phenomena by identifying the relevant parts of cells, the biochemical operations they performed, and the way in which these parts and operations were organised to accomplish important functions. Cell biology was a revolutionary science but in this book it also provides fuel for yet another revolution, one that (...) focuses on the very conception of science itself. Laws have traditionally been regarded as the primary vehicle of explanation, but in the emerging philosophy of science it is mechanisms that do the explanatory work. Bechtel emphasises how mechanisms were discovered, focusing especially on the way in which new instruments made these inquiries possible. He also describes how new journals and societies provided institutional structure to this new enterprise. (shrink)

Talk of different types of cells is commonplace in the biological sciences. We know a great deal, for example, about human muscle cells by studying the same type of cells in mice. Information about cell type is apparently largely projectible across species boundaries. But what defines cell type? Do cells come pre-packaged into different natural kinds? Philosophical attention to these questions has been extremely limited [see e.g., Wilson (Species: New Interdisciplinary Essays, pp 187–207, 1999; Genes and (...) the Agents of Life, 2005; Wilson et al. Philos Top 35(1/2):189–215, 2007)]. On the face of it, the problems we face in individuating cellular kinds resemble those biologists and philosophers of biology encountered in thinking about species: there are apparently many different (and interconnected) bases on which we might legitimately classify cells. We could, for example, focus on their developmental history (a sort of analogue to a species’ evolutionary history); or we might divide on the basis of certain structural features, functional role, location within larger systems, and so on. In this paper, I sketch an approach to cellular kinds inspired by Boyd’s Homeostatic Property Cluster Theory, applying some lessons from this application back to general questions about the nature of natural kinds. (shrink)

Research in many fields of biology has been extremely successful in decomposing biological mechanisms to discover their parts and operations. It often remains a significant challenge for scientists to recompose these mechanisms to understand how they function as wholes and interact with the environments around them. This is true of the eukaryotic cell. Although initially identified in nineteenth-century cell theory as the fundamental unit of organisms, researchers soon learned how to decompose it into its organelles and chemical constituents and have (...) been highly successful in understanding how these carry out many operations important to life. The emphasis on decomposition is particularly evident in modern cell biology, which for the most part has viewed the cell as merely a locus of the mechanisms responsible for vital phenomena. The cell, however, is also an integrated system and for some explanatory purposes it is essential to recompose it and understand it as an organized whole. I illustrate both the virtues of decomposition (treating the cell as a locus) and recomposition (treating the cell as an object) with recent work on circadian rhythms. Circadian researchers have both identified critical intracellular operations that maintain endogenous oscillations and have also addressed the integration of cells into multicellular systems in which cells constitute units. Ó 2010 Elsevier Ltd. All rights reserved. (shrink)

(Recipient of the 2020 Everett Mendelsohn Prize.) This article revisits the development of the protoplasm concept as it originally arose from critiques of the cell theory, and examines how the term “protoplasm” transformed from a botanical term of art in the 1840s to the so-called “living substance” and “the physical basis of life” two decades later. I show that there were two major shifts in biological materialism that needed to occur before protoplasm theory could be elevated to have equal status (...) with cell theory in the nineteenth century. First, I argue that biologists had to accept that life could inhere in matter alone, regardless of form. Second, I argue that in the 1840s, ideas of what formless, biological matter was capable of dramatically changed: going from a “coagulation paradigm” that had existed since Theophrastus, to a more robust conception of matter that was itself capable of movement and self-maintenance. In addition to revisiting Schleiden and Schwann’s original writings on cell theory, this article looks especially closely at Hugo von Mohl’s definition of the protoplasm concept in 1846, how it differed from his primordial utricle theory of cell structure two years earlier. This article draws on Lakoff and Johnson’s theory of “ontological metaphors” to show that the cell, primordial utricle, and protoplasm can be understood as material container, object, and substance, and that these overlapping distinctions help explain the chaotic and confusing early history of cell theory. (shrink)

While the clinical promise of much stem cell research remains largely theoretical, patients are nonetheless pursuing unproven stem cell therapies in jurisdictions around the world—a phenomenon referred to as “stem cell tourism.” These treatments are generally advertised on a direct-to-consumer basis via the Internet. Research shows portrayals of stem cell medicine on such websites are overly optimistic and the claims made are unsubstantiated by published evidence. However, anecdotal evidence suggests that parents are pursing these “treatments” for their children, despite potential (...) physical and financial risk. Physicians are in a unique position as they can be expected to be involved in, or privy to, such decisions. In this paper, we consider what duties physicians may have toward minor patients whose parents/guardians wish to engage in stem cell tourism on their behalf. We use the Canadian perspective to address the broadly relevant issues raised by this trend. (shrink)

Editor's suggested further reading in BioEssaysA new paradigm in cell therapy for diabetes: Turning pancreatic α‐cells into β‐cells Abstract.

The differentiation of male and female characteristics in vertebrates and insects has long been thought to proceed via different mechanisms. Traditionally, vertebrate sexual development was thought to occur in two phases: a primary and a secondary phase, the primary phase involving the differentiation of the gonads, and the secondary phase involving the differentiation of other sexual traits via the influence of sex hormones secreted by the gonads. In contrast, insect sexual development was thought to depend exclusively on cell‐autonomous expression of (...) sex‐specific genes. Recently, however, new evidence indicates that both vertebrates and insects rely on sex hormones as well as cell‐autonomous mechanisms to develop sexual traits. Collectively, these new data challenge the traditional vertebrate definitions of primary and secondary sexual development, call for a redefinition of these terms, and indicate the need for research aimed at explaining the relative dependence on cell‐autonomous versus hormonally guided sexual development in animals. (shrink)

The stunning possibility of “reprogramming” differentiated somatic cells to express a pluripotent stem cell phenotype (iPS, induced pluripotent stem cell) and the “ground state” character of pluripotency reveal fundamental features of cell fate regulation that lie beyond existing paradigms. The rarity of reprogramming events appears to contradict the robustness with which the unfathomably complex phenotype of stem cells can reliably be generated. This apparent paradox, however, is naturally explained by the rugged “epigenetic landscape” with valleys representing “preprogrammed” attractor (...) states that emerge from the dynamical constraints of the gene regulatory network. This article provides a pedagogical primer to the fundamental principles of gene regulatory networks as integrated dynamic systems and reviews recent insights in gene expression noise and fate determination, thereby offering a formal framework that may help us to understand why cell fate reprogramming events are inherently rare and yet so robust. (shrink)

Ontologies of living things are increasingly grounded on the concepts and practices of current life science. Biological development is a process, undergone by living things, which begins with a single cell and (in an important class of cases) ends with formation of a multicellular organism. The process of development is thus prima facie central for ideas about biological individuality and organismality. However, recent accounts of these concepts do not engage developmental biology. This paper aims to fill the gap, proposing the (...) lineage view of stem cells as an ontological framework for conceptualizing organismal development. This account is grounded on experimental practices of stem cell research, with emphasis on new techniques for generating biological organization in vitro. On the lineage view, a stem cell is the starting point of a cell lineage with a specific organismal source, time-interval of existence, and ‘tree topology’ of branch-points linking the stem to developmental termini. The concept of ‘enkapsis’ accommodates the cell-organism relation within the lineage view; this hierarchical notion is further explicated by considering the methods and results of stem cell experiments. Results of this examination include a (partial) characterization of stem cells’ developmental versatility, and the context-dependence of developmental processes involving stem cells. (shrink)

(2013). Sickle Cell Disease and the “Difficult Patient” Conundrum. The American Journal of Bioethics: Vol. 13, No. 4, pp. 3-10. doi: 10.1080/15265161.2013.767954.

In this paper the permissibility of stem cell research on early human embryos is defended. It is argued that, in order to have moral status, an individual must have an interest in its own wellbeing. Sentience is a prerequisite for having an interest in avoiding pain, and personhood is a prerequisite for having an interest in the continuation of one's own existence. Early human embryos are not sentient and therefore they are not recipients of direct moral consideration. Early human embryos (...) do not satisfy the requirements for personhood, but there are arguments to the effect that they should be treated as persons nonetheless. These are the arguments from potentiality, symbolic value and the principle of human dignity. These arguments are challenged in this paper and it is claimed that they offer us no good reason to believe that early human embryos should be treated as persons. (shrink)

This paper examines a case of failed interdisciplinary collaboration, between experimental stem cell research and theoretical systems biology. Recently, two groups of theoretical biologists have proposed dynamical systems models as a basis for understanding stem cells and their distinctive capacities. Experimental stem cell biologists, whose work focuses on manipulation of concrete cells, tissues and organisms, have largely ignored these proposals. I argue that ‘failure to communicate’ in this case is rooted in divergent views of explanation: the theoretically-inclined modelers (...) are committed to a version of the covering-law view, while experimental stem cell biologists aim at mechanistic explanations. I propose a way to reconcile these two explanatory approaches to cell development, and discuss the significance of this result for interdisciplinary collaboration in systems biology and beyond. (shrink)

B‐cell acute lymphoblastic leukaemia (B‐ALL) is a clonal malignant disease originated in a single cell and characterized by the accumulation of blast cells that are phenotypically reminiscent of normal stages of B‐cell differentiation. B‐ALL origin has been a subject of continuing discussion, given the fact that human disease is diagnosed at late stages and cannot be monitored during its natural evolution from its cell of origin, although most B‐ALLs probably start off with chromosomal changes in haematopoietic stem cells. (...) However, the cells responsible for maintaining the disease appear to differ between the different types of B‐ALLs and this remains an intriguing and exciting topic of research, since these cells have been posited to be responsible for resistance to conventional therapies, recurrence and dissemination. During the last years this problem has been addressed primarily by transplantation of purified subpopulations of human B‐ALL cells into immunodeficient mice. The results from these different reconstitution experiments and their interpretations are compared in this review in the context of normal B‐cell developmental plasticity. While the results from different research groups might appear mutually exclusive, we discuss how they could be reconciled with the biology of normal B‐cells and propose research avenues for addressing these issues in the future. (shrink)

Cell membranes experience frequent stretching and poking: from cytoskeletal elements, from osmotic imbalances, from fusion and budding of vesicles, and from forces from the outside. Are the ensuing changes in membrane tension localized near the site of perturbation, or do these changes propagate rapidly through the membrane to distant parts of the cell, perhaps as a mechanical mechanism of long‐range signaling? Literature statements on the timescale for membrane tension to equilibrate across a cell vary by a factor of ≈106. This (...) study reviews and discusses how apparently contradictory findings on tension propagation in cells can be evaluated in the context of 2D hydrodynamics and poroelasticity. Localization of tension in the cell membrane is likely critical in governing how membrane forces gate ion channels, set the subcellular distribution of vesicle fusion, and regulate the dynamics of cytoskeletal growth. Furthermore, in this study, it is proposed that cells can actively regulate the degree to which membrane tension propagates by modulating the density and arrangement of immobile transmembrane proteins. Also see the video abstract here https://youtu.be/T6K7AIAqqBs. (shrink)

Recent advances in stem cell research suggest that in the future it may be possible to create eggs and sperm from human stem cells through a process that we term in vitro gametogenesis (IVG). IVG would allow treatment of some currently untreatable forms of infertility. It may also allow same-sex couples to have genetically-related children. For example, cells taken from one man could potentially be used to create an egg, which could then be fertilised using naturally produced sperm (...) from another man to create a genetically-related child with half of its DNA from each of the men. In this chapter, we consider whether this technology could justifiably be denied to same-sex couples if it were made available as a fertility treatment to different-sex couples. We argue that it could not. (shrink)