No Going Back: Un-Fixing the Future of De-Extinction

‘Extinction is a colossal problem facing the world’ proclaims the Colossal Laboratories & Biosciences website, adding, ‘And Colossal is the company that’s going to fix it’. For Colossal, this involves combining the science of genetics with ‘the business of discovery’ in order to bring back the woolly mammoth, which will not only help ‘rewild’ lost habitats, but also contribute toward ‘making humanity more human’. De-extinction is the process through which extinct species can be brought back into existence, often with the goal of reintroducing species to the wild and restoring ecosystems. While still in its nascent state, the science of de-extinction is currently expanding and advancing through, for instance, projects like Colossal’s, raising numerous ethical, social and technological debates about what defines a species, and thus its regeneration; how such definitions shape conservation paradigms; and, ultimately, what we mean when we talk about life, death and species extinction. With their commitment to ‘reversing climate change’ while also ‘advanc[ing] the economies of biology and healing through genetics’, Colossal’s work has not only been deemed ‘game-changing’ in terms of “saving” endangered species, but also in terms of ‘future proofing’ the environment by reshaping how the world thinks about the power of genetics for solving pressing challenges in the life sciences today, including the challenge of extinction. In this de-extinction example, then, the problem of extinction is actualized in relation to solutions aimed at enacting further control over the planet, this time by ‘rewinding’ and ‘reversing’ ecological destruction, so as to fix the human-caused disaster, and in so doing, fix the future. In this essay, I trace the line between ‘the business of discovery’ and ‘making humanity more human’ in order to draw out what I see as some of the broader refrains and fixations that have come to infect future-oriented ecological discourse in these times of dying. Looking to the example of Colossal, I examine the ways in which extinction, and the corollary project of de-extinction, has become at once a territorializing force that works to re-install monohumanist fantasies of planetary control, and a potentially deterritorializing force for letting go and giving up

Effects of a synthetic bioactive peptide on neurite growth and nerve growth factor release in chondroitin sulfate hydrogels.

Previous work has revealed robust dorsal root ganglia neurite growth in hydrogels of chondroitin sulfate. In the current work, it was determined whether addition of a synthetic bioactive peptide could augment neurite growth in these matrices via enhanced binding and sequestering of growth factors. Fluorescence recovery after photobleaching studies revealed that addition of peptide slowed nerve growth factor diffusivity in chondroitin sulfate gels, but not in control gels of hyaluronic acid. Furthermore, cultures of chick dorsal root ganglia in gels of hyaluronic acid or chondroitin sulfate revealed enhanced growth in chondroitin sulfate gels only upon addition of peptide. Taken together, these results suggest a synergistic nerve growth factor-binding activity between this peptide and chondroitin sulfate

Cast Out: Vagrancy and Homelessness in Global and Historical Perspective

Throughout history, those arrested for vagrancy have generally been poor men and women, often young, able-bodied, unemployed, and homeless. Most histories of vagrancy have focused on the European and American experiences. Cast Out: Vagrancy and Homelessness in Global and Historical Perspective is the first book to consider the shared global heritage of vagrancy laws, homelessness, and the historical processes they accompanied. In this ambitious collection, vagrancy and homelessness are used to examine a vast array of phenomena, from the migration of labor to social and governmental responses to poverty through charity, welfare, and prosecution. The essays in Cast Out represent the best scholarship on these subjects and include discussions of the lives of the underclass, strategies for surviving and escaping poverty, the criminalization of poverty by the state, the rise of welfare and development programs, the relationship between imperial powers and colonized peoples, and the struggle to achieve independence after colonial rule. By juxtaposing these histories, the authors explore vagrancy as a common response to poverty, labor dislocation, and changing social norms, as well as how this strategy changed over time and adapted to regional peculiarities. Part of a growing literature on world history, Cast Out offers fresh perspectives and new research in fields that have yet to fully investigate vagrancy and homelessness. This book by leading scholars in the field is for policy makers, as well as for courses on poverty, homelessness, and world history. Contributors: Richard B. Allen, David Arnold, A. L. Beier, Andrew Burton, Vincent DiGirolamo, Andrew A. Gentes, Robert Gordon, Frank Tobias Higbie, Thomas H. Holloway, Abby Margolis, Paul Ocobock, Aminda M. Smith, Linda Woodbridgehttps://ohioopen.library.ohio.edu/oupress/1000/thumbnail.jp

Immunologic Aspects of Perioperative Nutrition

Nutrition has proven to be of great importance for the postoperative clinical outcome. Several studies have shown that infectious complications in the surgical patient , are reduced by pre- or postoperative nourishment. We discuss cellular immunity in relation to both enteral and parenteral nutrition and present an updated literature study of current evidence. The aim of this paper is to give an overview of studies, that compare different immunological parameters in the surgical patient being nourished either enterally or parenterally

Tracking Lysosome Migration within Chinese Hamster Ovary (CHO) Cells Following Exposure to Nanosecond Pulsed Electric Fields

Above a threshold electric field strength, 600 ns-duration pulsed electric field (nsPEF) exposure substantially porates and permeabilizes cellular plasma membranes in aqueous solution to many small ions. Repetitive exposures increase permeabilization to calcium ions (Ca2+) in a dosage-dependent manner. Such exposure conditions can create relatively long-lived pores that reseal after passive lateral diffusion of lipids should have closed the pores. One explanation for eventual pore resealing is active membrane repair, and an ubiquitous repair mechanism in mammalian cells is lysosome exocytosis. A previous study shows that intracellular lysosome movement halts upon a 16.2 kV/cm, 600-ns PEF exposure of a single train of 20 pulses at 5 Hz. In that study, lysosome stagnation qualitatively correlates with the presence of Ca2+ in the extracellular solution and with microtubule collapse. The present study tests the hypothesis that limitation of nsPEF-induced Ca2+ influx and colloid osmotic cell swelling permits unabated lysosome translocation in exposed cells. The results indicate that the efforts used herein to preclude Ca2+ influx and colloid osmotic swelling following nsPEF exposure did not prevent attenuation of lysosome translocation. Intracellular lysosome movement is inhibited by nsPEF exposure(s) in the presence of PEG 300-containing solution or by 20 pulses of nsPEF in the presence of extracellular calcium. The only cases with no significant decreases in lysosome movement are the sham and exposure to a single nsPEF in Ca2+-free solution

Destruction of single species biofi lms of Escherichia coli or Klebsiella pneumoniae subsp. pneumoniae by dextranase, lactoferrin, and lysozyme

The aim of this work was to determine the destructive activity of dextranase, lactoferrin, and lysozyme, against single species biofi lms composed of either Klebsiella pneumoniae subsp. pneumoniae or Escherichia coli using the MBEC Assay. Luminescence measurements based on quantitation of the ATP present were used to determine the amount of biofi lm elimination and correlated with quantity of live bacteria present in the sample. The data were analyzed employing a two-way ANOVA and Bonferroni post-test. Treatments resulted in percentage reductions of E. coli biofi lms ranging from 73 to 98 %. Lactoferrin (40 μg/ml) produced a signifi cantly higher-percentage reduction than lysozyme (10 μg/ml) (P < 0.05), no other signifi cant differences occurred. Similar treatments resulted in percentage reductions of K. pneumoniae subsp. pneumoniae biofilms ranging from 51 to 100 %. Dextranase treatments produced a signifi cantly lower percentage reduction than all other materials (P < 0.05), no other signifi cant differences occurred. No material was capable of complete destruction of both single species biofi lms; however, low concentrations of lactoferrin and lysozyme each removed 100 % of the K. pneumoniae subsp. pneumoniae biofi lm. Low concentrations of lactoferrin or lysozyme might be benefi cial to prevent biofi lm formation by K. pneumoniae subsp. pneumoniae. [Int Microbiol 2012; 15(4):183-187

Agouti C57BL/6N embryonic stem cells for mouse genetic resources.

We report the characterization of a highly germline competent C57BL/6N mouse embryonic stem cell line, JM8. To simplify breeding schemes, the dominant agouti coat color gene was restored in JM8 cells by targeted repair of the C57BL/6 nonagouti mutation. These cells provide a robust foundation for large-scale mouse knockout programs that aim to provide a public resource of targeted mutations in the C57BL/6 genetic background

Conditional expression of the TVA receptor allows clonal analysis of descendents from Cre-expressing progenitor cells

AbstractAn understanding of the number and types of progeny produced by progenitor cells during development provides a foundation for studies of when and where cell fate determination takes place. Lineal relationships can be revealed by the identification of descendents of cells that express a recombinase, such as Cre or Flp. This method provides data concerning gene expression history, but does not provide clonal resolution among the descendents. An alternative method employs retroviral labeling, which permits the identification of clones, but does not allow for the tracking of gene expression history. Here we report a combination of these methods to circumvent each method's limitations. By employing the specificity of Cre expression, and by selecting only a subset of cells with a Cre history for retroviral infection, clones with a gene expression history can be labeled. The method utilizes a conditional allele of the avian tumor virus receptor A (TVA), which allows infection of mouse cells following Cre activity, with mammalian retroviral vectors pseudotyped with the ASLV-A envelope glycoprotein (EnvA). We quantified the efficiency and specificity of this system in vivo and in vitro. We also generated a series of retroviral vectors encoding a variety of histochemical and fluorescent reporter genes that enable the tracking of mixtures of clones, thus enabling better resolution of clonal boundaries. This method and new vectors can be used to further our understanding of the gene expression patterns of progenitor cells that make particular daughter cells, as well as provide a platform for manipulating identified subsets of developing cells