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1.
The distinction between the recognition of an individual using an automated biometric system and the fundamental notion of their identity is subtle and therefore provokes much debate relating to privacy and other societal issues. This article seeks to clarify some of these issues relating to biometric recognition and identity by providing a framework, and by distinguishing between the technology and societal issues.  相似文献   

2.
The evaluation of product alternatives in Life Cycle Analysis (LCA) is a critical step on the basis of results as related to their impact category data. Decisions involving several environmental issues are hardly ever straightforward, since one alternative only seldom clearly dominates the others in all aspects. More often, one alternative scores better on some environmental issues and worse on others. A combination of impact data and preferences is then required for evaluation. This can be done using evaluation methods based on fixed societal preferences. However, by applying different evaluation methods to the same data, different “best” alternatives may be chosen. This reduces the credibility of LCA results. Instead of fixed societal preferences an approach has been developed which uses consensus-oriented ranges of societal values for specifying the ranking of the overall environmental attractiveness of alternatives. These ranges may indicate both the uncertainty of decision-makers and the shifting of societal values, e.g. as related to the dynamics of knowledge of environmental problem areas. In this article, an approach is proposed which combines environmental data and uncertain societal values to form a clear statement on alternatives regarding their overall damage. By using a full set of potentially relevant societal preferences, a merely coincidental selection of the best product alternative is ruled out. A step-by-step procedure, narrowing down the feasible range of societal preferences, has been developed. The approach is illustrated using a case study of TV-housing concepts and a survey.  相似文献   

3.
Biological Invasions - Globally, invasive plant-fueled wildfires have tremendous environmental, economical, and societal impacts, and the frequencies of wildfires and plant invasions are on an...  相似文献   

4.
Valorization of knowledge has been defined as a major challenge in the context of genomics as an emerging strategic research field. Valorization is a Dutch science-policy concept for what is elsewhere called science impact or the third mission of universities. This article describes the institutionalization of valorization policy in the Dutch genomics research system as a specific manifestation of a changing social contract between science and society, which mainly targets economic value creation and the stimulation of entrepreneurship. A societal debate has emerged in which this focus on economic aspects has been strongly criticized as one-sided. In response, policy-makers are willing to adopt a broader definition of valorization. On the basis of an analysis of valorization policies and practices in Dutch medical genomics, this article draws attention to two myths in this valorization debate.  相似文献   

5.
Laberge CM  Knoppers BM 《Bioethics》1992,6(4):317-330
Conclusion: Genetic knowledge is now in the public domain and its interpretation by the media and the citizens brings the issues into the public forum of discussion for the necessary ethical, legal and socio-cultural evaluation of its application. Science is being perceived by some as dangerous and as requiring international regulation. Others feel that genetic knowledge will be the breakthrough that will permit medical progress and individual autonomy with regards to personal health and lifestyle choices. The mapping of the human genome has already yielded valuable information on an increasing number of diseases and their variants. Prevailing popular and journalistic archetypes ("imaginaires") used in the media are perceived by the producers as slowing down the possible application of genetic knowledge. The answers to these dilemmas are not readily apparent nor are they prescribed by classical philosophy of medicine. Since genetic knowledge eventually resides with the individual who carries the genes of disease and/or susceptibility, a logical approach to integration of this knowledge at a societal level would seem to reside with individual education and decision-making. The politics of the ensuing social debate could transform the current social contract since an individual's interests need to be balanced against those of his or her immediate family in the sharing of information. The ethical foundations of such a contract requires the genetic education of "Everyone" as a matter of urgent priority. Genetic education should not serve ideological power struggles between the medical establishment and the ethical-legal alliance. Instead, it should ensure the transfer of knowledge to physicians, to patients, to users, to planners, to social science and humanities researchers and to politicians, so that they may make "informed" and free decisions....  相似文献   

6.
As part of the SYNBIOSAFE project, we carried out an open electronic conference (e-conference), with the aim to stimulate an open debate on the societal issues of synthetic biology in a proactive way. The e-conference attracted 124 registered participants from 23 different countries and different professional backgrounds, who wrote 182 contributions in six different categories: (I) Ethics; (II) Safety; (III) Security; (IV) IPR; (V) Governance and regulation; (VI) and Public perception. In this paper we discuss the main arguments brought up during the e-conference and provide our conclusions about how the community thinks, and thinks differently on the societal impact of synthetic biology. Finally we conclude that there is a chance for an open discourse on the societal issues of synthetic biology happening, and that the rules to govern such a discourse might be set up much easier and be respected more readily than many would suggest.  相似文献   

7.
Elevation of cyclic GMP by muscarinic agonists has been suggested to be responsible for the negative inotropic effects of these agents in cardiac muscle, and for the endothelium-dependent relaxation caused by these agents in vascular smooth muscle. These relationships were studied by monitoring the effects of muscarinic agonists on tension and cyclic GMP levels in rabbit left atrial strips and aortic rings, in the presence and absence of the cyclic GMP lowering agent, LY83583. LY83583 completely blocked both the cyclic GMP increase and the relaxation caused by acetylcholine in rabbit aortic rings with intact endothelial cells. Acetylcholine-induced cyclic GMP elevation and relaxation in these preparations were also blocked by quinacrine and nordihydroguaiaretic acid (NDGA), but neither response was blocked by the 5-lipoxygenase inhibitor U-60257. In the experiments with rabbit left atrium, LY83583 blocked the acetylcholine-induced cyclic GMP elevation but did not block the negative inotropic effects of the drug. Quinacrine, NDGA, and a guanylate cyclase inhibitor, methylene blue, failed to block either the cyclic GMP increase or the decrease in contractile force caused by carbachol in atrial strips. These results support the suggestion that an increase in cyclic GMP may be responsible for the endothelium-dependent relaxation of rabbit aorta by muscarinic agonists, but not for the direct negative inotropic effects of these drugs in rabbit atrium. Muscarinic agents appear to increase cyclic GMP levels in rabbit atrium and aorta by different mechanisms. Although both are blocked by LY83583, they differ not only in their requirements for endothelial cells, but also in their susceptibility to other blocking agents.  相似文献   

8.
Abstract— The effect of light on the content of cyclic GMP in degenerative retinae of Royal College of Surgeons (RCS) rats and rd mice was compared with that in control retinae during postnatal maturation. In vivo, the cyclic GMP content of retinae of control rats or mice is light-dependent after photoreceptor outer segments develop. Mature retinae of control animals have high levels of cyclic GMP in the dark which are reduced 40–50% upon illumination. In the rd mouse disorder, a light-induced reduction in cyclic GMP content is observed while the rod outer segments are morphologically intact. The rd photoreceptor cells possess a phosphodiesterase which, when stabilized by freeze-drying, has a Km similar to that of control photoreceptors, and an apparent Vmax that is below normal. It is suggested that developing rd visual cells have an abnormality in cyclic GMP metabolism which results in the accumulation of cyclic GMP within the entire cell but which does not prevent the light-mediated reduction of cyclic GMP in their outer segment organelles. In the RCS dystrophy, a light-induced reduction in cyclic GMP content is observed also during the period when photoreceptor outer segments are present. The cyclic GMP content of dark- or light-adapted RCS retinae is below that of the respective controls. Biochemical and morphological observations show that cyclic GMP levels increase in rd visual cells and that they are reduced in photoreceptor cells of RCS retina before the onset of visual cell degeneration. Until detailed knowledge of the role of cyclic GMP in the visual cells is known, it is suggested that high or low levels of cyclic GMP in rd and RCS photoreceptors, respectively, result from differences in the etiology or histopathology of the mouse and rat diseases.  相似文献   

9.
Inactivation of hypoxanthine phosphoribosyltransferase caused by periodate-oxidized GMP is irreversible, even under the conditions of polyacrylamide gel electrophoresis and during affinity chromatography on GMP-Sepharose. Partial binding of the inhibitor to the enzyme protein can be demonstrated on dodecyl sulfate gel electrophoresis: The substrate, phosphoribosyl diphosphate in the presence of Mg2, and the product GMP protect the enzyme against inactivation. Periodate-oxidized GMP, AMP and oxidized purine nucleosides do not influence ribosephosphate pyrophosphokinase, 5'-nucleotidase, purine-nucleoside phosphorylase and guanylate kinase. A variety of other purine nucleosides and nucleotides, tested in their periodateoxidized form, do not lead to a compound comparable or superior to oxidized GMP in its effect on hypoxanthine phosphoribosyltransferase. In an erythrocyte system it is clearly demonstrated that oxidized GMP cannot act across an intact cell membrane.  相似文献   

10.
Abstract: The effects of arginine on calcium mobilization in human SK-N-SH neuroblastoma cells were examined. It was found that arginine potentiated an increase in carbachol-induced Ca2+ from the external Ca2+ influx as opposed to an internal Ca2+ release from intracellular pools. The potentiation effect of arginine on carbachol-induced calcium mobilization was mimicked by either 8-bromo cyclic GMP or sodium nitroprusside. In addition, it was found that arginine induced NO production and an increase in cyclic GMP. Moreover, arginine-induced potentiation, NO production, and cyclic GMP increases were all suppressed after the preincubation of cells with N -methyl- l -arginine or N -nitro- l -arginine, nitric oxide synthase inhibitor. It is suggested that the NO production and subsequent cyclic GMP elevation induced by arginine are responsible for the potentiation of carbachol-induced Ca2+ increase. Our results show the existence of a NO/cyclic GMP pathway and an interconnection of NO and Ca2+ signaling pathways in human SK-N-SH neuroblastoma cells. We also observed that NO, which is produced by endothelial CPAE cells, has a modulating effect on cyclic GMP elevation in human SK-N-SH neuroblastoma cells. The intercellular communication role of NO and its cell-diffusing character may also affect the regulation of nonneuronal cells in their interactions with neuronal cells.  相似文献   

11.
Primary, first and second passaged endothelial cells from bovine aorta were grown in plastic culture dishes or on glass coverslips. The cells were characterized by their monolayer cobblestone appearance at confluence, their immunofluorescent staining for factor VIII-related antigen, their specific uptake of low density lipoprotein and by their ultrastructure. Following stimulation of the cells by atriopeptin II or sodium nitroprusside, both cellular and extracellular cyclic GMP levels were measured. Cellular cyclic GMP content was increased greatly by atriopeptin II in a time-dependent manner while sodium nitroprusside was essentially without effect. Increases in tissue cyclic GMP levels were associated with a time-dependent accumulation of the nucleotide in the extracellular compartment. Zaprinast, a specific inhibitor of cyclic GMP phosphodiesterases, did not significantly affect either basal or atriopeptin II-stimulated increases in cyclic GMP content, nor extracellular accumulation of the nucleotide. It is concluded that the cyclic GMP content of endothelial cells is not solely dependent on degradation by phosphodiesterases but also involves release of cyclic GMP into the extracellular compartment.  相似文献   

12.
Bacteria live predominantly in biofilms, and the internal signal cyclic diguanylate (c‐di‐GMP) is a universal signal that governs the formation and the dispersal of these communities. Pseudomonas aeruginosa is one of the most important reference systems for studying bacterial biofilms and contains numerous diguanylate cyclases (DGCs) for synthesizing c‐di‐GMP and phosphodiesterases (PDEs) for degrading c‐di‐GMP. However, few studies have discerned how cells in biofilms respond to their environment to regulate c‐di‐GMP concentrations through this sophisticated network of enzymes. Basu Roy and Sauer (2014) provide insights on how cells disperse in response to an increase in nutrient levels. Their results show that the inner membrane protein NicD is a DGC that controls dispersal by sensing nutrient levels: when glutamate concentrations are increased, NicD is dephosphorylated, which increases c‐di‐GMP levels and leads to phosphorylation and processing of dispersal regulator BdlA. Processing of BdlA leads to activation of PDE DipA, which results in a net reduction of c‐di‐GMP and biofilm dispersal. These results suggest biofilm dispersal relies on surprisingly dynamic c‐di‐GMP concentrations as a result of a sophisticated interaction between DGCs and PDEs.  相似文献   

13.
The levels of cyclic AMP and cyclic GMP have been measured in Physarum plasmodia before and after treatment with gamma-radiation, 2 mM caffeine, or combinations of the two agents and compared to the length of the radiation-induced mitotic delay. Caffeine alone produces a rapid transient elevation of cyclic AMP and a slower delayed elevation of cyclic GMP. Irradiation elicits an immediate transient increase in cyclic AMP and a later cyclic GMP increase which accompanies or precedes the delayed mitosis. A composite pattern is produced by combinations of radiation and caffeine, a distinctive feature of which is an elevated level of cyclic GMP near the time of the radiation-delayed and caffeine-promoted mitosis. With pretreatment by caffeine, the least radiation-induced mitotic delay occurs when plasmodia are irradiated during the caffeine-elicited increase in cyclic GMP. The plasmodium becomes refractory to the reduction of mitotic delay by caffeine at approximately the time it becomes refractory to the further elevation of cyclic GMP by caffeine. The data support a role for cyclic AMP in the onset of and for cyclic GMP in the recovery from mitotic delay induced by ionizing radiation.  相似文献   

14.
In many bacterial pathogens, the second messenger c‐di‐GMP stimulates the production of an exopolysaccharide (EPS) matrix to shield bacteria from assaults of the immune system. How c‐di‐GMP induces EPS biogenesis is largely unknown. Here, we show that c‐di‐GMP allosterically activates the synthesis of poly‐β‐1,6‐N‐acetylglucosamine (poly‐GlcNAc), a major extracellular matrix component of Escherichia coli biofilms. C‐di‐GMP binds directly to both PgaC and PgaD, the two inner membrane components of the poly‐GlcNAc synthesis machinery to stimulate their glycosyltransferase activity. We demonstrate that the PgaCD machinery is a novel type c‐di‐GMP receptor, where ligand binding to two proteins stabilizes their interaction and promotes enzyme activity. This is the first example of a c‐di‐GMP‐mediated process that relies on protein–protein interaction. At low c‐di‐GMP concentrations, PgaD fails to interact with PgaC and is rapidly degraded. Thus, when cells experience a c‐di‐GMP trough, PgaD turnover facilitates the irreversible inactivation of the Pga machinery, thereby temporarily uncoupling it from c‐di‐GMP signalling. These data uncover a mechanism of c‐di‐GMP‐mediated EPS control and provide a frame for c‐di‐GMP signalling specificity in pathogenic bacteria.  相似文献   

15.
Biobanks include biological samples and attached databases. Human biobanks occur in research, technological development and medical activities. Population genomics is highly dependent on the availability of large biobanks. Ethical issues must be considered: protecting the rights of those people whose samples or data are in biobanks (information, autonomy, confidentiality, protection of private life), assuring the non-commercial use of human body elements and the optimal use of samples and data. They balance other issues, such as protecting the rights of researchers and companies, allowing long-term use of biobanks while detailed information on future uses is not available. At the level of populations, the traditional form of informed consent is challenged. Other dimensions relate to the rights of a group as such, in addition to individual rights. Conditions of return of results and/or benefit to a population need to be defined. With 'large-scale biobanking' a marked trend in genomics, new societal dimensions appear, regarding communication, debate, regulation, societal control and valorization of such large biobanks. Exploring how genomics can help health sector biobanks to become more rationally constituted and exploited is an interesting perspective. For example, evaluating how genomic approaches can help in optimizing haematopoietic stem cell donor registries using new markers and high-throughput techniques to increase immunogenetic variability in such registries is a challenge currently being addressed. Ethical issues in such contexts are important, as not only individual decisions or projects are concerned, but also national policies in the international arena and organization of democratic debate about science, medicine and society.  相似文献   

16.
Cyclic guanosine 3′,5′-monophosphate (cyclic GMP) stimulates nucleic acid synthesis in lymphocytes, and has been implicated as the intracellular effector of the actions of mitogenic agents on these cells. In the present study, we examined the specificity of the mitogenic activity of cyclic GMP and of its 8-bromo (Br) derivatives, and the effects of the T cell mitogens, concanavalin A, phytohemagglutinin, and staphylococcal entertoxin B (SEB) on the cyclic GMP content and guanylate cyclase activity of mouse splenic lymphocytes. Cyclic GMP and guanosine modestly increased the incorporation of [3H]thymidine into DNA by cultured lymphocytes, but were far less effective than their 8-Br-derivatives. However, on a molar basis the mitogenic activity of both 8-Br-guanosine and 8-Br-5′-GMP exceeded that of 8-Br-cyclic GMP, when tested in the presence and absence of serum in the culture media. Combined addition of maximal doses of these nucleotides did not give additive stimulatory effects, suggesting an action on a common subpopulation of cells, and possibly a common mechanism. By contrast, cyclic AMP, 8-Br-cyclic AMP, 8-Br-adenosine, cholera toxin and prostaglandin E1 suppressed both basal [3]thymidine incorporation and stimulation of this parameter by T-cell line mitogens and the guanosine nucleotides. Rapid effects of concanavalin A, phytohemagglutinin, SEB, guanosine, 5′-GMP, 8-Br-guanosine, and 8-Br-5′-GMP on the cyclic GMP content of murine lymphocytes could not be demonstrated. Similarly, concanalin A, phytohemagglutinin and SEB failed to alter guanylate cyclase activity when added directly to cellular homogenates or pre-incubated with intact cels. Conversely, carbamylcholine rapidly increased lymphocyte cyclic GMP but was not mitogenic.These results are consistent with the hypothesis that cyclic GMP and cyclic AMP are antagonistic in their influence on lymphocyte mitogenesis. However, they also demonstrate that related nucleotides are more potent mitogens than cyclic GMP and suggest that activation of murine lymphocytes by concanavalin A, phytohemagglutinin and SEB may not be mediated by rapid increases in cellular cyclic GMP content. Since high concentrations of exogenous cyclic GMP and related nucleotides must be used to influence DNA synthesis, the biologic significance of this effect remains uncertain.  相似文献   

17.
Guanylate kinase is an essential enzyme in the nucleotide biosynthetic pathway, catalyzing the reversible transfer of the terminal phospharyl group of ATP to GMP or dGMP. This enzyme has been well studied from several organisms and many structural and functional details have been characterized. Animal GMP kinases have also been implicated in signal transduction pathways. However, the corresponding role by plant derived GMP kinases remains to be elucidated. Full-length cDNA clones encoding enzymatically active guanylate kinases were isolated from cDNA libraries of lily and tobacco. Lily cDNA is predicted to encode a 392-amino acid protein with a molecular mass of 43.1 kDa and carries amino- and carboxy- terminal extensions of the guanylate kinase (GK)-like domain. But tobacco cDNA is predicted to encode a smaller protein of 297-amino acids with a molecular mass of 32.7 kDa. The amino acid residues known to participate in the catalytic activity of functionally characterized GMP kinases, are also conserved in GK domains of LGK-1 and NGK-1. The GK domains of NGK-1, LGK-1 and previously characterized AGK-1 from Arabidopsis exhibit 74–84% identity, whereas their N- and C-terminal domains are more divergent with amino acid conservation in the order of 48-55%. Phylogenetic analysis on the deduced amino acid sequences reveals that NGK-1 and LGK-1 form one distinct subgroup along with AGK-1 and AGK-2 homologues from Arabidopsis. Isolation of GMP kinases from diverse plant species like lily and tobacco adds a new dimension in understanding their role in cell signaling pathways that are associated with plant growth and development.  相似文献   

18.
19.
Evidence is presented for Ca2+ and cyclic GMP being involved in signal transduction between the cell surface cyclic AMP receptors and cytoskeletal myosin II involved in chemotactic cell movement. Ca2+ is shown to be required for chemotactic aggregation of amoebae. The evidence for uptake and/or eflux of this ion being regulated by the nucleotide cyclic GMP is discussed. The connection between Ca2+, cyclic GMP and chemotactic cell movement has been explored using “streamer F” mutants. The primary defect in these mutants is in the structural gene for the cyclic GMP-specific phosphodiesterase which results in the mutants producing an abnormally prolonged peak of accumulation of cyclic GMP in response to stimulation with the chernoattractant cyclic AMP. While events associated with production and relay of cyclic AMP signals are normal, certain events associated with movement are (like the cyclic GMP response) abnormally prolonged in the mutants. These events include Ca2+ uptake, myosin II association with the cytoskeleton and inhibition of myosin heavy and light chain phosphorylation. These changes can be correlated with the amoebae becoming elongated and transiently decreasing their locomotive speed after chemotactic stimulation. Other mutants studied in which the accumulation of cyclic GMP in response to cyclic AMP stimulation was absent produced no myosin II responses. Models are described in which cyclic GMP (directly or indirectly via Ca2+) regulates accumulation of myosin II on the cytoskeleton by inhibiting phosphorylation of the myosin heavy and light chain kinases.  相似文献   

20.
Nanotechnology could produce a revolutionary wave of innovation in society. The form that such a revolution might take will depend upon many things but certainly upon the context, content and purposes of research projects and agendas decided by existing political and corporate institutions. Lessons from the genetically modified organism debate indicate that the behaviour of these institutions is at least as important as the 'risk' in informing public acceptability. This article argues that current research priorities need to shift in favour of environmental and health protection to engender public support and/or an ongoing need to remain sensitive to emerging societal preferences.  相似文献   

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