| 1. |
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| 2. |
- Juth, Niklas, 1973, et al.
(författare)
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The Ethics of Screening in Health Care and Medicine: Serving Society or Serving the Patient?
- 2012
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- Medical or health-oriented screening programs are amongst the most debated aspects of health care and public health practices in health care and public health ethics, as well as health policy discussions. In spite of this, most treatments of screening in the research literature restrict themselves to isolated scientific aspects, sometimes complemented by economic analyses or loose speculations regarding policy aspects. At the same time, recent advances in medical genetics and technology, as well as a rapidly growing societal focus on public health concerns, inspires an increase in suggested or recently started screening programs. This book involves an in-depth analysis of the ethical, political and philosophical issues related to health-oriented screening programs. It explores the considerations that arise when heath care interacts with other societal institutions on a large scale, as is the case with screening: What values may be promoted or compromised by screening programs? What conflicts of values do typically arise – both internally and in relation to the goals of health care, on the one hand, and the goals of public health and the general society, on the other? What aspects of screening are relevant for determining whether it should be undertaken or not and how it should be organised in order to remain defensible? What implications does the ethics of screening have for health care ethics as a whole? These questions are addressed by applying philosophical methods of conceptual analysis, as well as models and theories from moral and political philosophy, medical ethics, and public health ethics, to a large number of ongoing and proposed screening programs which makes this book the first comprehensive work on the ethics of screening. Analyses and suggestions are made that are of potential interest to health care staff, medical researchers, policy makers and the general public.
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| 3. |
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| 4. |
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| 5. |
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| 6. |
- Cutas, Daniela, 1978, et al.
(författare)
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Legal imperialism in the regulation of stem cell research and therapy: the problem of extraterritorial jurisdiction
- 2010
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Ingår i: Capps BJ & Campbell AV (eds.). CONTESTED CELLS: Global Perspectives on the Stem Cell Debate. - London : Imperial College Press. - 9781848164376 ; , s. 95-119
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Countries worldwide have very different national regulations on human embryonic stem (ES) cell research, informed by a range of ethical values. Some countries find reason to extend the applicability of their regulations on such research to its citizens when they visit other countries. Extraterritorial jurisdiction has recently been identified as a potential challenge towards global regulation of ES cell research. This chapter explores the implications and impact of extraterritorial jurisdiction and global regulation of ES cell research on researchers, clinicians and national health systems, and how this may affect patients. The authors argue that it would make ethical sense for ES cell restrictive countries to extend its regulations on ES cell research beyond its borders, because, if these countries really consider embryo destruction to be objectionable on the basis on the status of the embryo, then they ought to count it morally on par with murder (and thus have a moral imperative to protect embryos from the actions of its own citizens). However, doing so could lead to a legal situation that would result in substantial harm to central values in areas besides research, such as health care, the job market, basic freedom of movement, and strategic international finance and politics. Thus, it seems that restrictive extraterritorial jurisdiction in respect to ES cell research would be deeply problematic, given that the ethical permissibility of ES cell research is characterised by deep and wide disagreement.
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| 7. |
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| 8. |
- Munthe, Christian, 1962
(författare)
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The Price of Precaution and the Ethics of Risk
- 2011
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- Since a couple of decades, the notion of a precautionary principle plays a central and increasingly influential role in international as well as national policy and regulation regarding the environment and the use of technology. Urging society to take action in the face of potential risks of human activities in these areas, the recent focus on climate change has further sharpened the importance of this idea. However, the idea of a precautionary principle has also been problematised and criticised by scientists, scholars and policy activists, and been accused of almost every intellectual sin imaginable: unclarity, impracticality, arbitrariness and moral as well as political unsoundness. In that light, the very idea of precaution as an ideal for policy making rather comes out as a dead end. On the basis of these contrasting starting points, Christian Munthe undertakes an innovative, in-depth philosophical analysis of what the idea of a precautionary principle is and should be about. A novel theory of the ethics of imposing risks is developed and used as a foundation for defending the idea of precaution in environmental and technological policy making against its critics, while at the same time avoiding a number of identified flaws. The theory is shown to have far-reaching consequences for areas such as bio-, information- and nuclear technology, and global environmental policy in areas such as climate change. The author argues that, while the price we pay for precaution must not be too high, we have to be prepared to pay it in order to act ethically defensible. A number of practical suggestions for precautionary regulation and policy making are made on the basis of this, and some challenges to basic ethical theory as well as consumerist societies, the global political order and liberal democracy are identified
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| 9. |
- Munthe, Christian, 1962, et al.
(författare)
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The Return of Lombroso? Ethical Aspects of (Visions of) Preventive Forensic Screening
- 2015
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Ingår i: Public Health Ethics. - : Oxford University Press (OUP). - 1754-9973 .- 1754-9981. ; 8:3, s. 270-283
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Tidskriftsartikel (refereegranskat)abstract
- The vision of legendary criminologist Cesare Lombroso to use scientific theories of individual causes of crime as a basis for screening and prevention programmes targeting individuals at risk for future criminal behaviour has resurfaced, following advances in genetics, neuroscience and psychiatric epidemiology. This article analyses this idea and maps its ethical implications from a public health ethical standpoint. Twenty-seven variants of the new Lombrosian vision of forensic screening and prevention are distinguished, and some scientific and technical limitations are noted. Some lures, biases and structural factors, making the application of the Lombrosian idea likely in spite of weak evidence are pointed out and noted as a specific type of ethical aspect. Many classic and complex ethical challenges for health screening programmes are shown to apply to the identified variants and the choice between them, albeit with peculiar and often provoking variations. These variations are shown to actualize an underlying theoretical conundrum in need of further study, pertaining to the relationship between public health ethics and the ethics and values of criminal law policy.
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| 10. |
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| 11. |
- Munthe, Christian, 1962
(författare)
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Etiska aspekter på regenerativ medicin : Ethical aspects on regenerative medicine
- 2003
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Ingår i: SNIB-konferensen 2003, Chalmers tekniska högskola, Göteborg, 16-18 maj 2003.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Inom den regenerativa medicinen strävar man efter att ersätta skadat eller sjukligt biologiskt mänskligt material (celler, organ, kroppsdelar) med nya biologiska komponenter. Området aktualiserar en rad etiska frågeställningar vad gäller (1) produktionen av ersättningsmaterialet (t.ex. embryonala stamceller eller införskaffande av transplantationsvävnad från donatorer), (2) risker i samband med försök på människa (genmodifierat material, material från djur), samt (3) gränserna för hur långt man bör gå i denna slags försök att förlänga människans livsspann. Föredraget ger en kort översikt över dessa frågeställningar, ståndpunkter och argument i debatten kring dem.
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| 12. |
- Munthe, Christian, 1962
(författare)
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A New Ethical Landscape of Prenatal Testing: Individualizing Choice to Serve Autonomy and Promote Public Health: A Radical Proposal
- 2015
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Ingår i: Bioethics. - : Wiley. - 0269-9702 .- 1467-8519. ; 29:1, s. 36-45
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Tidskriftsartikel (refereegranskat)abstract
- A new landscape of prenatal testing (PNT) is presently developing, including new techniques for risk-reducing, non-invasive sampling of foetal DNA and drastically enhanced possibilities of what may be rapidly and precisely analysed, surrounded by a growing commercial genetic testing industry and a general trend of individualization in healthcare policies. This article applies a set of established ethical notions from past debates on PNT for analysing PNT screening-programmes in this new situation. While some basic challenges of PNT stay untouched, the new development supports a radical individualization of how PNT screening is organized. This reformation is, at the same time, difficult to reconcile with responsible spending of resources in a publicly funded healthcare context. Thus, while the ethical imperative of individualization holds and applies to PNT, the new landscape of PNT provides reasons to start rolling back the type of mass-screening programmes currently established in many countries. Instead, more limited offers are suggested, based on considerations of severity of conditions and optimized to simultaneously serve reproductive autonomy and public health within an acceptable frame of priorities. The new landscape of PNT furthermore underscores the ethical importance of supporting and including people with disabilities. For the very same reason, no ban on what may be analysed using PNT in the new landscape should be applied, although private offers must, of course, conform to strict requirements of respecting reproductive autonomy and what that means in terms of counselling.
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| 13. |
- Munthe, Christian, 1962
(författare)
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Will IVF ever be the norm?
- 2014
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Ingår i: Future of IVF - A Brave New World? ESHRE symposium, September 26-27, Stockholm.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 14. |
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| 15. |
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| 16. |
- Wiszmeg, Andréa, et al.
(författare)
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Transforming trash to treasure Cultural ambiguity in foetal cell research
- 2021
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Ingår i: Philosophy Ethics and Humanities in Medicine. - : Springer Science and Business Media LLC. - 1747-5341. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Background Rich in different kind of potent cells, embryos are used in modern regenerative medicine and research. Neurobiologists today are pushing the boundaries for what can be done with embryos existing in the transitory margins of medicine. Therefore, there is a growing need to develop conceptual frameworks for interpreting the transformative cultural, biological and technical processes involving these aborted, donated and marginal embryos. This article is a contribution to this development of frameworks. Methods This article examines different emotional, cognitive and discursive strategies used by neurobiologists in a foetal cell transplantation trial in Parkinson's disease research, using cells harvested from aborted embryos. Two interviews were analysed in the light of former observations in the processing laboratories, using the anthropologist Mary Douglas's concept of pollution behaviour and the linguist, philosopher, psychoanalyst and feminist Julia Kristeva's concept of the abjective to explain and make sense of the findings. Results The findings indicate that the labour performed by the researchers in the trial work involves transforming the foetal material practically, as well as culturally, from trash to treasure. The transformation process contains different phases, and in the interview material we observed that the foetal material or cells were considered objects, subjects or rejected as abject by the researchers handling them, depending on what phase of process or practice they referred to or had experience of. As demonstrated in the analysis, it is the human origin of the cell that makes it abjective and activates pollution discourse, when the researchers talk of their practice. Conclusions The marginal and ambiguous status of the embryo that emerges in the accounts turns the scientists handling foetal cells into liminal characters in modern medicine. Focusing on how practical as well as emotional and cultural strategies and rationalizations of the researchers emerge in interview accounts, this study adds insights on the rationale of practically procuring, transforming and utilizing the foetal material to the already existing studies focused on the donations. We also discuss why the use and refinement of a tissue, around which there is practical consensus but cultural ambiguity, deserves further investigation.
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| 17. |
- Jing, Yujia, 1985
(författare)
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Hyperthermia-responsive liposomal systems
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Abstract Sophisticated liposomal systems are emerging at an increasing rate to meet the demands for multifunctional drug carriers in chemotherapies in combined with hyperthermia. For example, liposomal drug carriers for temperature-controlled drug release under hyperthermic conditions have recently been tested in clinical trials. More advanced designs of liposomes are expected to release encapsulated contents and activate hidden surface-functions in response to heat stimulus. Towards this aim, the present thesis is focused on formulating asymmetric lipid systems that can preserve functional moieties, and reactivate the targeted function as well as release the encapsulated compounds upon local heating. The design of the asymmetric liposomal systems utilizes the heat-activated transmembrane lipid diffusion during gel to liquid-crystalline phase transitions of the lipid membranes.Rational design of advanced liposomal drug-delivery systems will require understanding of the physicochemical properties of lipid membranes under, e.g., hyperthermic conditions. Here, supported lipid membranes on planar solid surfaces were used for model studies of lipid composition yielding a gel to liquid crystalline phase-transition temperature in the range 40 – 45 °C. It was found that the liposome-to-membrane formation process is not only size-dependent but also governed by temperature. Two methods of preparing supported asymmetric lipid membranes were investigated. As a proof-of-concept, the upper leaflets were either replaced or chemically transformed by enzymatic hydrolysis. The processes were monitored using surface sensitive techniques such as quartz crystal microbalance with dissipation (QCM-D) and dual polarization interferometry (DPI). The asymmetric structures were stable at a room temperature, while lipid flip-flop was induced upon increasing of the temperature. Transmembrane lipid exchange in the asymmetric structure under hyperthermic conditions was demonstrated by detecting, through streptavidin binding, biotinylated lipids appearing at the top leaflet which were first located in the lower leaflet. The protocols developed for the supported lipid systems were adapted for the preparation of asymmetric liposomes. Biotinylated asymmetric liposomes were used as a model system to demonstrate the principle of heat-activated targeting of asymmetric liposomes to streptavidin-coated surfaces. More biologically relevant interaction was utilized to replace the biotin-streptavidin function, where asymmetric cationic liposomes were binding to anionic supported membrane immobilized surfaces upon heating. The described strategies for assembly of asymmetric supported membranes provide a guide to the development of multifunctional drug carriers. The protocols used in experiments with supported membranes were readily adapted to the preparation of asymmetric liposomes. The ongoing study tests the asymmetric liposomes in vitro, which is designed to demonstrate hyperthermia treatment can enhance accumulation of liposomes in FaDu cells, and at the same time activate release of the encapsulated components. The results of in vitro tests can be used to analyze the feasibility of utilizing the asymmetric liposomes as a platform in vivo to explore further improvement in their functions upon microwave hyperthermia.
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| 18. |
- Munthe, Christian, 1962
(författare)
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Pure Selection. The Ethics of Preimplantation Genetic Diagnosis and Choosing Children without Abortion
- 1999
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- Preimplantation ge¬netic diagnosis (PGD) is taken to mark the starting-point of a new phase in human reproduction, where the possibility of choosing children on genetic grounds without having to resort to ethi¬cally controversial procedures (such as abortion) will grad¬ually increase. Ethical and political issues actu¬alised by this develop¬ment are addressed. The discussion touches upon issues regarding the moral status of em¬bryos and gametes, the moral import of respecting individual auton¬omy and its implications for the requirement of informed consent in health-care, the connec¬tion between sickness, dis¬ability and the value of life, the moral status of possible future people, and the connection between choosing children and eugenic policies of the past. Practical policy issues are adressed on the basis of this, as well as an empirical case-study of the intro¬duction of PGD in Sweden. The book ends up in a set of recommendations regarding the management of re¬search on, introduction and routine use of procedures for pure se¬lection, both within health care and from the point of view of society as a whole. It is argued that research on such procedures should be allowed and supported by society. However, tight restrictions regarding the clinical introduction of new procedures in this area is highly desirable. A rough model for implementing such re¬strictions is also pre¬sented. It is further asserted that, although reasons of economy and safety should limit the access to pure se¬lection, society should not apply any explicit restrictions based on ideasregarding how different traits affect a person’s quality of life. It is stressed that, in order to to avoid a re¬sur¬rection of eugenic policies of the past, the development in this field un¬der¬lines the need for continued and strengthen public support to the sick, dis¬abled and mentally retarded.
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| 19. |
- Trigo, João Pedro, 1995, et al.
(författare)
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In vitro digestibility and Caco-2 cell bioavailability of sea lettuce (Ulva fenestrata) proteins extracted using pH-shift processing
- 2021
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Ingår i: Food Chemistry. - : Elsevier BV. - 0308-8146 .- 1873-7072. ; 356
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Tidskriftsartikel (refereegranskat)abstract
- Seaweed is a promising sustainable source of vegan protein as its farming does not require arable land, pesticides/insecticides, nor freshwater supply. However, to be explored as a novel protein source the content and nutritional quality of protein in seaweed need to be improved. We assessed the influence of pH-shift processing on protein degree of hydrolysis (%DH), protein/peptide size distribution, accessibility, and cell bioavailability of Ulva fenestrata proteins after in vitro gastrointestinal digestion. pH-shift processing of Ulva, which concentrated its proteins 3.5-times, significantly improved the %DH from 27.7±2.6% to 35.7±2.1% and the amino acid accessibility from 56.9±4.1% to 72.7±0.6%. Due to the higher amino acid accessibility, the amount of most amino acids transported across the cell monolayers was higher in the protein extracts. Regarding bioavailability, both Ulva and protein extracts were as bioavailable as casein. The protein/peptide molecular size distribution after digestion did not disclose a clear association with bioavailability.
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| 20. |
- Palmquist, Anders, 1977, et al.
(författare)
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Complex geometry and integrated macro-porosity: Clinical applications of electron beam melting to fabricate bespoke bone-anchored implants
- 2023
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Ingår i: Acta Biomaterialia. - : Elsevier BV. - 1742-7061 .- 1878-7568. ; 156, s. 125-145
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Forskningsöversikt (refereegranskat)abstract
- The last decade has witnessed rapid advancements in manufacturing technologies for biomedical implants. Additive manufacturing (or 3D printing) has broken down major barriers in the way of producing complex 3D geometries. Electron beam melting (EBM) is one such 3D printing process applicable to metals and alloys. EBM offers build rates up to two orders of magnitude greater than comparable laser-based technologies and a high vacuum environment to prevent accumulation of trace elements. These features make EBM particularly advantageous for materials susceptible to spontaneous oxidation and nitrogen pick-up when exposed to air (e.g., titanium and titanium-based alloys). For skeletal reconstruction(s), anatomical mimickry and integrated macro-porous architecture to facilitate bone ingrowth are undoubtedly the key features of EBM manufactured implants. Using finite element modelling of physiological loading conditions, the design of a prosthesis may be further personalised. This review looks at the many unique clinical applications of EBM in skeletal repair and the ground-breaking innovations in prosthetic rehabilitation. From a simple acetabular cup to the fifth toe, from the hand-wrist complex to the shoulder, and from vertebral replacement to cranio-maxillofacial reconstruction, EBM has experienced it all. While sternocostal reconstructions might be rare, the repair of long bones using EBM manufactured implants is becoming exceedingly frequent. Despite the various merits, several challenges remain yet untackled. Nevertheless, with the capability to produce osseointegrating implants of any conceivable shape/size, and permissive of bone ingrowth and functional loading, EBM can pave the way for numerous fascinating and novel applications in skeletal repair, regeneration, and rehabilitation. Statement of significance: Electron beam melting (EBM) offers unparalleled possibilities in producing contaminant-free, complex and intricate geometries from alloys of biomedical interest, including Ti6Al4V and CoCr. We review the diverse range of clinical applications of EBM in skeletal repair, both as mass produced off-the-shelf implants and personalised, patient-specific prostheses. From replacing large volumes of disease-affected bone to complex, multi-material reconstructions, almost every part of the human skeleton has been replaced with an EBM manufactured analog to achieve macroscopic anatomical-mimickry. However, various questions regarding long-term performance of patient-specific implants remain unaddressed. Directions for further development include designing personalised implants and prostheses based on simulated loading conditions and accounting for trabecular bone microstructure with respect to physiological factors such as patient's age and disease status.
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| 21. |
- Trigo, João Pedro, 1995, et al.
(författare)
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Mild blanching prior to pH-shift processing of Saccharina latissima retains protein extraction yields and amino acid levels of extracts while minimizing iodine content
- 2023
-
Ingår i: Food Chemistry. - : Elsevier BV. - 0308-8146 .- 1873-7072. ; 404
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Tidskriftsartikel (refereegranskat)abstract
- The seaweed Saccharina latissima is often blanched to lower iodine levels, however, it is not known how blanching affects protein extraction. We assessed the effect of blanching or soaking (80/45/12 °C, 2 min) on protein yield and protein extract characteristics after pH-shift processing of S. latissima. Average protein yields and extract amino acid levels ranked treatments as follows: blanching-45 °C ∼ control > soaking ∼ blanching-80 °C. Although blanching-45 °C decreased protein solubilization yield at pH 12, it increased isoelectric protein precipitation yield at pH 2 (p < 0.05). The former could be explained by a higher ratio of large peptides/proteins in the blanched biomass as shown by HP-SEC, whereas the latter by blanching-induced lowering of ionic strength, as verified by a dialysis model. Moreover, blanching-45 °C yielded a protein extract with 49 % less iodine compared with the control extract. We recommend blanching-45 °C since it is effective at removing iodine and does not compromise total protein extraction yield.
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| 22. |
- Andersson, Sören, 1957-, et al.
(författare)
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CHIMERIC MOMP ANTIGEN
- 2015
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Patent (populärvet., debatt m.m.)
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| 23. |
- Gillman, Anna, et al.
(författare)
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Oseltamivir-Resistant Influenza A (H1N1) Virus Strain with an H274Y Mutation in Neuraminidase Persists without Drug Pressure in Infected Mallards
- 2015
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Ingår i: Applied and Environmental Microbiology. - : American Society for Microbiology. - 0099-2240 .- 1098-5336. ; 81:7, s. 2378-2383
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Tidskriftsartikel (refereegranskat)abstract
- Influenza A virus (IAV) has its natural reservoir in wild waterfowl and emerging human IAVs often contain gene segments from avian viruses. The active drug metabolite of oseltamivir (oseltamivir carboxylate (OC)), stockpiled as Tamiflu® for influenza pandemic preparedness, is not removed by conventional sewage treatment and has been detected in river water. There, it may there exert evolutionary pressure on avian IAV in waterfowl, resulting in development of resistant viral variants. A resistant avian IAV can circulate among wild birds only if resistance does not restrict viral fitness and if the resistant virus can persist without continuous drug pressure. In this in vivo Mallard (Anas platyrhynchos) study we tested if an OC-resistant avian IAV strain (A(H1N1)/NA-H274Y) could retain resistance while drug pressure was gradually removed. Successively infected Mallards were exposed to decreasing levels of OC, and fecal samples were analyzed for neuraminidase sequence and phenotypic resistance. No reversion to wild-type virus was observed during the experiment, which included 17 days of viral transmission in 10 ducks exposed to OC concentrations below resistance induction levels. We conclude that resistance in avian IAV, induced by OC exposure of the natural host, can persist in absence of the drug. Thus, there is a risk that human pathogenic IAVs that evolve from IAVs circulating among wild birds may contain resistance mutations. An oseltamivir resistant pandemic IAV would be a substantial public health threat. Therefore, our observations underscore the need for prudent oseltamivir use, upgraded sewage treatment and resistance surveillance of IAV in wild birds.
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| 24. |
- Checinska, Aleksandra, et al.
(författare)
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Microbiomes of the dust particles collected from the International Space Station and Spacecraft Assembly Facilities
- 2015
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Ingår i: Microbiome. - : Springer Science and Business Media LLC. - 2049-2618. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- Background - The International Space Station (ISS) is a unique built environment due to the effects of microgravity, space radiation, elevated carbon dioxide levels, and especially continuous human habitation. Understanding the composition of the ISS microbial community will facilitate further development of safety and maintenance practices. The primary goal of this study was to characterize the viable microbiome of the ISS-built environment. A second objective was to determine if the built environments of Earth-based cleanrooms associated with space exploration are an appropriate model of the ISS environment. Results - Samples collected from the ISS and two cleanrooms at the Jet Propulsion Laboratory (JPL, Pasadena, CA) were analyzed by traditional cultivation, adenosine triphosphate (ATP), and propidium monoazide–quantitative polymerase chain reaction (PMA-qPCR) assays to estimate viable microbial populations. The 16S rRNA gene Illumina iTag sequencing was used to elucidate microbial diversity and explore differences between ISS and cleanroom microbiomes. Statistical analyses showed that members of the phyla Actinobacteria, Firmicutes, and Proteobacteria were dominant in the samples examined but varied in abundance. Actinobacteria were predominant in the ISS samples whereas Proteobacteria, least abundant in the ISS, dominated in the cleanroom samples. The viable bacterial populations seen by PMA treatment were greatly decreased. However, the treatment did not appear to have an effect on the bacterial composition (diversity) associated with each sampling site. Conclusions - The results of this study provide strong evidence that specific human skin-associated microorganisms make a substantial contribution to the ISS microbiome, which is not the case in Earth-based cleanrooms. For example, Corynebacterium and Propionibacterium (Actinobacteria) but not Staphylococcus (Firmicutes) species are dominant on the ISS in terms of viable and total bacterial community composition. The results obtained will facilitate future studies to determine how stable the ISS environment is over time. The present results also demonstrate the value of measuring viable cell diversity and population size at any sampling site. This information can be used to identify sites that can be targeted for more stringent cleaning. Finally, the results will allow comparisons with other built sites and facilitate future improvements on the ISS that will ensure astronaut health.
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| 25. |
- Munthe, Christian, 1962
(författare)
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Precaution, bioethics and normative justification
- 2015
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Ingår i: Monash Bioethics Review. - : Springer Science and Business Media LLC. - 1321-2753 .- 1836-6716. ; 33:2, s. 219-225
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Recension (övrigt vetenskapligt/konstnärligt)abstract
- Daniel Steel’s new book on the precautionary principle illustrates the need to work ahead to fuse perspectives of epistemology and philosophy of science with those of ethics to accomplish progress in the debate on the proper role of precaution in a broad selection of bioethical areas. Steel advances the territory greatly with regard to conceptual clarity and epistemology, but from a bioethics standpoint he is mistaken in discounting the need for ethical underpinnings of a sound theory of the precautionary principle.
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| 26. |
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| 27. |
- Munthe, Christian, 1962
(författare)
-
Precautionary Principle
- 2013
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Ingår i: International Encyclopedia of Ethics. - Chichester : Blackwell. - 9781444367072 ; , s. 4031-4039
-
Bokkapitel (refereegranskat)abstract
- Following the statement in the United Nations' Rio Declaration of 1992 that countries should apply a “precautionary approach” in policymaking on environmental and technological issues, the notion of a precautionary principle (PP) has gained ground in worldwide policymaking and regulation, thus catching the interest of ethics scholars. Although seldom explained in much detail, and resulting in quite different policy results in different countries and areas (O'Riordan et al. 2001; Sandin 1999; Trouwborst 2002; Zander 2010), PP is generally understood as a norm urging or permitting policymakers to take preventive action in the face of unknown, uncertain, or probable dangers, motivated by the experience of how seemingly valuable and promising practices may lead to seriously adverse consequences in spite of lack of solid evidence to this effect (Sandin 1999). In ethics debate, this idea has been applied not only to matters regarding the large-scale introduction and use of technology (e.g., regarding energy production, transport and communication, nano- or biotechnology, and so on) (see Biotechnology; Nanotechnology, Ethics of) with possible ensuing impact on the natural environment connecting to the notion of sustainability (see Sustainability), but also, for example, to abortion (see Abortion), medical genetics, embryo experimentation (see Embryo Research), the treatment of animals (see Animal Experimentation), terrorism (see Terrorism), and general research ethics (see Research Ethics) (Munthe 2011). Many of these applications advocate strong conclusions in spite of the fact that PP or its normative justification have not been made very clear. At the same time, PP has been the subject of criticism, much of which boils down to three points: lack of clarity, lack of practicality, and/or ethical implausibility. Curiously, these critical points have often been made in conjunction, in spite of the fact that a clear sense of what PP means seems necessary for backing up the other two objections.
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| 28. |
- Gund, Anna, 1980, et al.
(författare)
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Design Evaluation of a Home-Based Telecare System for Chronic Heart Failure Patients
- 2008
-
Ingår i: Engineering in Medicine and Biology Society, 2008. EMBS 2008. 30th Annual International Conference of the IEEE. - : IEEE. - 1557-170X. - 9781424418145 ; , s. 5851-5854, s. 5851-5854
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Konferensbidrag (refereegranskat)abstract
- In order to improve the care of Chronic Heart Failure (CHF) patients, a system has been developed for monitoring symptoms and document subjective judgments on health conditions in a home environment. Since system usability is an important issue, a two step evaluation of the solution was conducted. First a ten-patient survey was conducted, which was aimed at spotting possible problem areas. The second step involved a small trial in a home setting with CHF patients. The results are promising, indicating that the system is user friendly and easy to use, and that it is suitable as a prototype for the intended use.
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| 29. |
- Memedi, Mevludin, et al.
(författare)
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Validity and responsiveness of at-home touch-screen assessments in advanced Parkinson's disease
- 2015
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Ingår i: IEEE journal of biomedical and health informatics. - : Institute of Electrical and Electronics Engineers (IEEE). - 2168-2194 .- 2168-2208. ; 19:6, s. 1829-1834
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to investigate if a telemetry test battery can be used to measure effects of Parkinson’s disease (PD) treatment intervention and disease progression in patients with fluctuations. Sixty-five patients diagnosed with advanced PD were recruited in an open longitudinal 36-month study; 35 treated with levodopa-carbidopa intestinal gel (LCIG) and 30 were candidates for switching from oral PD treatment to LCIG. They utilized a test battery, consisting of self-assessments of symptoms and fine motor tests (tapping and spiral drawings), four times per day in their homes during week-long test periods. The repeated measurements were summarized into an overall test score (OTS) to represent the global condition of the patient during a test period. Clinical assessments included ratings on Unified PD Rating Scale (UPDRS) and 39-item PD Questionnaire (PDQ-39) scales. In LCIG-naïve patients, mean OTS compared to baseline was significantly improved from the first test period on LCIG treatment until month 24. In LCIG-non-naïve patients, there were no significant changes in mean OTS until month 36. The OTS correlated adequately with total UPDRS (rho = 0.59) and total PDQ-39 (0.59). Responsiveness measured as effect size was 0.696 and 0.536 for OTS and UPDRS respectively. The trends of the test scores were similar to the trends of clinical rating scores but dropout rate was high. Correlations between OTS and clinical rating scales were adequate indicating that the test battery contains important elements of the information of well-established scales. The responsiveness and reproducibility were better for OTS than for total UPDRS.
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| 30. |
- Rems, Lea, et al.
(författare)
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Cell electrofusion using nanosecond electric pulses
- 2013
-
Ingår i: Scientific Reports. - : Macmillan Publishers Ltd.. - 2045-2322. ; 3
-
Tidskriftsartikel (refereegranskat)abstract
- Electrofusion is an efficient method for fusing cells using short-duration high-voltage electric pulses. However, electrofusion yields are very low when fusion partner cells differ considerably in their size, since the extent of electroporation (consequently membrane fusogenic state) with conventionally used microsecond pulses depends proportionally on the cell radius. We here propose a new and innovative approach to fuse cells with shorter, nanosecond (ns) pulses. Using numerical calculations we demonstrate that ns pulses can induce selective electroporation of the contact areas between cells (i.e. the target areas), regardless of the cell size. We then confirm experimentally on B16-F1 and CHO cell lines that electrofusion of cells with either equal or different size by using ns pulses is indeed feasible. Based on our results we expect that ns pulses can improve fusion yields in electrofusion of cells with different size, such as myeloma cells and B lymphocytes in hybridoma technology.
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| 31. |
- McGinn, Steven, et al.
(författare)
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New Technologies for DNA analysis-A review of the READNA Project.
- 2016
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Ingår i: New Biotechnology. - : Elsevier BV. - 1876-4347 .- 1871-6784.
-
Forskningsöversikt (refereegranskat)abstract
- The REvolutionary Approaches and Devices for Nucleic Acid analysis (READNA) project received funding from the European Commission for 4 1/2 years. The objectives of the project revolved around technological developments in nucleic acid analysis. The project partners have discovered, created and developed a huge body of insights into nucleic acid analysis, ranging from improvements and implementation of current technologies to the most promising sequencing technologies that constitute a 3(rd) and 4(th) generation of sequencing methods with nanopores and in situ sequencing, respectively.
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| 32. |
- Yewale, Priti, et al.
(författare)
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Studies on Biosmotrap : A multipurpose biological air purifier to minimize indoor and outdoor air pollution
- 2022
-
Ingår i: Journal of Cleaner Production. - : Elsevier. - 0959-6526 .- 1879-1786. ; 357
-
Tidskriftsartikel (refereegranskat)abstract
- Air pollution is a serious health concern that affects many people across the globe. The major air pollutants are particulate matter, carbon oxides, nitrogen oxides, sulphur oxides, volatile organic compounds, polycyclic aromatics and free radicals which cause severe respiratory distress and infections. The existing air cleaning systems suffer from drawbacks of high cost and generation of secondary pollutants. A novel biological air filter “Biosmotrap” which is a laminate composite of sponge gourd and algae was developed. Biosmotrap placed in a carrier assembly on exhaust of vehicles, could remove carbon monoxide, nitric oxide, nitrogen dioxide, and fine particulate matter (PM2.5) from the vehicular emissions resulting in cleaner emissions. Biosmotrap decreased carbon monoxide from 1,423,992 μg/m3 to 76,756 μg/m3, nitric oxide from 71,128 μg/m3 to 9982 μg/m3, nitrogen dioxide from 565 μg/m3 to 188 μg/m3 and PM2.5 from 3200 μg/m3 to 60 μg/m3 from a polluting vehicle. Biosmotrap removed 60–80% of indoor pollutants from cigarette smoke and incense-stick smoke. Biosmotrap could protect the human cells from oxidative DNA damage induced by indoor air pollutants. Hibiscus rosa-sinensis plants exposed to air filtered through Biosmotrap were healthy as compared to the plants directly exposed to polluted air. Biosmotrap is an economic, efficient, eco-friendly filter that is superior to existing air filtration methods.
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| 33. |
- Bakidou, Anna, 1996, et al.
(författare)
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On Scene Injury Severity Prediction (OSISP) model for trauma developed using the Swedish Trauma Registry
- 2023
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Ingår i: BMC Medical Informatics and Decision Making. - 1472-6947. ; 23:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Providing optimal care for trauma, the leading cause of death for young adults, remains a challenge e.g., due to field triage limitations in assessing a patient’s condition and deciding on transport destination. Data-driven On Scene Injury Severity Prediction (OSISP) models for motor vehicle crashes have shown potential for providing real-time decision support. The objective of this study is therefore to evaluate if an Artificial Intelligence (AI) based clinical decision support system can identify severely injured trauma patients in the prehospital setting. Methods: The Swedish Trauma Registry was used to train and validate five models – Logistic Regression, Random Forest, XGBoost, Support Vector Machine and Artificial Neural Network – in a stratified 10-fold cross validation setting and hold-out analysis. The models performed binary classification of the New Injury Severity Score and were evaluated using accuracy metrics, area under the receiver operating characteristic curve (AUC) and Precision-Recall curve (AUCPR), and under- and overtriage rates. Results: There were 75,602 registrations between 2013–2020 and 47,357 (62.6%) remained after eligibility criteria were applied. Models were based on 21 predictors, including injury location. From the clinical outcome, about 40% of patientswere undertriaged and 46% were overtriaged. Models demonstrated potential for improved triaging and yielded AUC between 0.80–0.89 and AUCPR between 0.43–0.62. Conclusions: AI based OSISP models have potential to provide support during assessment of injury severity. The findings may be used for developing tools to complement field triage protocols, with potential to improve prehospital trauma care and thereby reduce morbidity and mortality for a large patient population.
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| 34. |
- Munthe, Christian, 1962
(författare)
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Precautionary Principle
- 2015
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Ingår i: Encyclopedia of Global Bioethics. - Dordrecht : Springer. - 9783319055442
-
Bokkapitel (refereegranskat)abstract
- Precautionary reasoning has deep historical and wide cross-cultural roots in the ethics of health, health care, and medical research. As in general ethics, however, this side of bioethical thinking has not been the subject of focused critical analysis until recently. The emergence of the precautionary principle (PP) in general environmental and technology policy debate has, after an initial period of confusion, resulted in a range of possible ideas about the value of precaution and what sacrifices it may be worth. This has indicated some need for developments in ethical as well as decision theory. In bioethical debates, this process has left only vague traces, however. Although many issues exist where precautionary reasoning has a place, this is either often left unnoticed or arguments developed suffer from elementary flaws. Environmental and general public health ethics, the ethics of evidence-based practice in research, as well as clinical decision-making, management of normative or factual uncertainty, and the nature of clinical ethical virtues are all areas where precautionary ideas seem to have a place. Such reasoning moreover has specific relevance for global approaches to bioethics and health policy issues in a number of ways.
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| 35. |
- Bondesson, Johan, 1991, et al.
(författare)
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Definition of Tubular Anatomic Structures from Arbitrary Stereo Lithographic Surface
- 2017
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Ingår i: Initiative Seminar Engineering Health, 8-9 November 2017, Chalmers.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- An accurate description of anatomies and dynamics of vessels is crucial to understand their characteristics and improve surgical techniques, thus it is the basis, in addition to surgeon experience, on which stent design and operation procedures rely. The process of producing this description is user intensive, and recent improvement in image processing of medical3D imaging allows for a more automated workflow. However, there is a need to bridge the gap from a processed geometry to a robust mathematical computational grid. By sequentially segmenting a tubular anatomic structure, here defined by a stereo lithographic (STL) surface, an initial centerline is formed by connecting centroids of orthogonal cross-sectional contours along the length of the structure. Relying on the initial centerline, a set of non-overlapping 2D cross sectional contours are defined along the centerline, a centerline which is updated after the 2D contours are produced. After a second iteration of producing 2D contours and updating the centerline, a full description of the structure is created. Our method for describing vessel geometry shows good coherence to existing method. The main advantages of our method include the possibility of having arbitrary triangulated STL surface input, automated centerline definition, safety against intersecting cross-sectional contours and automatic clean-up of local kinks and wrinkles.
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| 36. |
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| 37. |
- Fu, Ying, 1964-, et al.
(författare)
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Endocytic pathway of vascular cell adhesion molecule 1 in human umbilical vein endothelial cell identified in vitro by using functionalized nontoxic fluorescent quantum dots
- 2019
-
Ingår i: Sensors and actuators. B, Chemical. - : Elsevier B.V.. - 0925-4005 .- 1873-3077. ; 297
-
Tidskriftsartikel (refereegranskat)abstract
- Studies about vascular cell adhesion molecule 1 (VCAM1) in tumor growth, metastasis, and angiogenesis suggest that targeting VCAM1 expression is an attractive strategy for diagnosis and anti-tumor therapy. However, the endocytic pathway of VCAM1 in vascular cells has not been well characterized. In this study we visualize the endocytic pathway of tumor necrosis factor α (TNFα) induced VCAM1 in human umbilical vein endothelial cell (HUVEC) in vitro using 5-carboxyfluorescein labeled VCAM1 binding peptides and fluorescent water-dispersible 3-mercaptopropionic acid (3MPA)-coated CdSe-CdS/Cd0.5Zn0.5S/ZnS core–multishell nontoxic quantum dots (3MPA-QDs) functionalized with VCAM1 binding peptides. Clear key in vitro observations are as follows: (a) 3MPA-QDs functionalized with VCAM1 binding peptides, denoted as VQDs, adhered and aggregated cumulatively to cell membrane around 2 h after VQD deposition to cell culture medium and were found in lysosomes in TNFα-treated HUVECs approximately 24 h after VQD deposition; (b) VQDs remained in TNFα-treated HUVECs for the whole 16 days of the experimental observation period; (c) quite differently, 3MPA-QDs were endocytosed then exocytosed by HUVECs via endosomes in about 24–48 h after 3MPA-QD deposition. Our study suggests that VCAM1 molecules, initially expressed on cell membrane induced by TNFα treatment, are internalized into lysosomes. This provides a novel means to deliver materials to lysosomes such as enzyme replacement therapy. Moreover, our meticulous sensing methodology of devising fluorescent nontoxic QDs advances biosensing technique for studying cellular activities in vitro and in vivo. © 2019 The Authors
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| 38. |
- Visuttijai, Kittichate, 1979-, et al.
(författare)
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Lowered Expression of Tumor Suppressor Candidate MYO1C Stimulates Cell Proliferation, Suppresses Cell Adhesion and Activates AKT
- 2016
-
Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 11:10
-
Tidskriftsartikel (refereegranskat)abstract
- Myosin-1C (MYO1C) is a tumor suppressor candidate located in a region of recurrent losses distal to TP53. Myo1c can tightly and specifically bind to PIP2, the substrate of Phosphoinositide 3-kinase (PI3K), and to Rictor, suggesting a role for MYO1C in the PI3K pathway. This study was designed to examine MYO1C expression status in a panel of well-stratified endometrial carcinomas as well as to assess the biological significance of MYO1C as a tumor suppressor in vitro. We found a significant correlation between the tumor stage and lowered expression of MYO1C in endometrial carcinoma samples. In cell transfection experiments, we found a negative correlation between MYO1C expression and cell proliferation, and MYO1C silencing resulted in diminished cell migration and adhesion. Cells expressing excess of MYO1C had low basal level of phosphorylated protein kinase B (PKB, a.k.a. AKT) and cells with knocked down MYO1C expression showed a quicker phosphorylated AKT (pAKT) response in reaction to serum stimulation. Taken together the present study gives further evidence for tumor suppressor activity of MYO1C and suggests MYO1C mediates its tumor suppressor function through inhibition of PI3K pathway and its involvement in loss of contact inhibition.
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| 39. |
- Sepehri, Sobhan, 1986, et al.
(författare)
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Homogeneous Differential Magnetic Assay
- 2019
-
Ingår i: Acs Sensors. - : American Chemical Society (ACS). - 2379-3694. ; 4:9, s. 2381-2388
-
Tidskriftsartikel (refereegranskat)abstract
- Assays are widely used for detection of various targets, including pathogens, drugs, and toxins. Homogeneous assays are promising for the realization of point-of-care diagnostics as they do not require separation, immobilization, or washing steps. For low concentrations of target molecules, the speed and sensitivity of homogeneous assays have hitherto been limited by slow binding kinetics, time-consuming amplification steps, and the presence of a high background signal. Here, we present a homogeneous differential magnetic assay that utilizes a differential magnetic readout that eliminates previous limitations of homogeneous assays. The assay uses a gradiometer sensor configuration combined with precise microfluidic sample handling. This enables simultaneous differential measurement sample containing a synthesized Vibrio cholerae target and a negative control sample, which reduces the background signal and increases the readout speed. Very low concentrations of targets down to femtomolar levels are thus detectable without any additional amplification of the number of targets. Our homogeneous differential magnetic assay method opens new possibilities for rapid and highly sensitive diagnostics at the point of care.
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| 40. |
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| 41. |
- Petzold, Martin, et al.
(författare)
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Towards an Ambient Assisted Living User Interaction Taxonomy
- 2013
-
Ingår i: CHI '13 Extended Abstracts of the ACM International Conference on Human Factors in Computing Systems. - New York : ACM Press. - 9781450318990 ; , s. 49-54
-
Konferensbidrag (refereegranskat)abstract
- Extensive research in the field of ambient assisted living (AAL) provides profound knowledge about the design of AAL systems. However, more generic design characteristics for user interaction have not been formalized for this domain yet. Thus, we propose to develop a domain specific taxonomy for the design of user interaction in AAL systems. We adopted a systematic taxonomy development approach that combines an empirical and a pseudo-conceptual strategy. Six co-researchers from different disciplines conduct the iterative research process. Next to AAL systems existing taxonomies in the field of human-computer interaction are analyzed following the Delphi method. In this paper we present our research process and preliminary results from the first iteration. The final taxonomy allows classification and should support the analysis of user interaction utilized in AAL systems. Furthermore, it can deal as a practical design guideline.
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| 42. |
- Ahluwalia, Bani, et al.
(författare)
-
Differences in Metabolite Composition of Aloe barbadensis Mill. Extracts Lead to Differential Effects on Human Blood T Cell Activity In Vitro
- 2022
-
Ingår i: Molecules. - : MDPI AG. - 1420-3049 .- 1420-3049. ; 27:19
-
Tidskriftsartikel (refereegranskat)abstract
- Aloe barbadensis Mill. (Aloe) is used for diverse therapeutic properties including immunomodulation. However, owing to the compositionally complex nature of Aloe, bioactive component(s) responsible for its beneficial properties, though thought to be attributed to polysaccharides (acemannan), remain unknown. We therefore aimed to determine the metabolite composition of various commercial Aloe extracts and assess their effects on human blood T cell activity in vitro. Peripheral blood mononuclear cells (PBMC) from healthy donors were stimulated polyclonally in presence or absence of various Aloe extracts. T cell phenotype and proliferation were investigated by flow cytometry. Aloe extracts were analyzed using targeted 1H-NMR spectroscopy for standard phytochemical quality characterization and untargeted gas chromatography mass spectrometry (GC-MS) for metabolite profiling. Aloe extracts differing in their standard phytochemical composition had varying effects on T cell activation, proliferation, apoptosis, and cell-death in vitro, although this was not related to the acemannan content. Furthermore, each Aloe extract had its own distinct metabolite profile, where extracts rich in diverse sugar and sugar-derivatives were associated with reduced T cell activity. Our results demonstrate that all commercial Aloe extracts are unique with distinct metabolite profiles, which lead to differential effects on T cell activity in vitro, independent of the acemannan content.
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| 43. |
- Orru, Anna Maria, 1976, et al.
(författare)
-
AHA! festival 2015
- 2015
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The AHA festival investigates the borders between art and science in a three-day event at the Chalmers University of Technology hosted by the Department of Architecture. An international festival intended to provide enlightening experiences, staging surprises, new thoughts and displaced perspectives that lead to alternative modes of thinking about the space between art and science. We invite scientists (physicists, historians, mathematicians, medical students), artists (dancers, musicians, painters, poets, chefs) and not least architects, who reside in these borderlands and wish to share their vision and work. The key intention is to celebrate both art and science as key knowledge building devices.
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| 44. |
- Andersson, Sören, 1957-, et al.
(författare)
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Chimeric MOMP antigen
- 2014
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Patent (populärvet., debatt m.m.)abstract
- The present invention regards polypeptides capable of eliciting an immunological response that is protective against Chlamydia trachomatis. The polypeptide comprises a first amino acid sequence which has at least 90% homology with the amino acid sequence according to SEQ ID NO: 1 and a second amino acid sequence which has at least 90% homology with the amino acid sequence according to SEQ ID NO: 2. Furthermore, production of these polypeptides and pharmaceutical compositions comprising them are also provided.
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| 45. |
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| 46. |
- Palsdottir, Vilborg, 1979, et al.
(författare)
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Postnatal deficiency of essential fatty acids in mice results in resistance to diet-induced obesity and low plasma insulin during adulthood
- 2011
-
Ingår i: Prostaglandins, Leukotrienes and Essential Fatty Acids. - : Elsevier BV. - 1532-2823 .- 0952-3278. ; 84:3-4, s. 85-92
-
Tidskriftsartikel (refereegranskat)abstract
- Our objective was to investigate the long-term metabolic effects of postnatal essential fatty acid deficiency (EFAD). Mouse dams were fed an EFAD diet or an isoenergetic control diet 4 days before delivery and throughout lactation. The pups were weaned to standard diet (STD) and were later subdivided into two groups: receiving high fat diet (HFD) or STD. Body composition, energy expenditure, food intake and leptin levels were analyzed in adult offspring. Blood glucose and plasma insulin concentrations were measured before and during a glucose tolerance test. EFAD offspring fed STD were leaner with lower plasma leptin and insulin concentrations compared to controls. EFAD offspring fed HFD were resistant to diet-induced obesity, had higher energy expenditure and lower levels of plasma leptin and insulin compared to controls. These results indicate that the fatty acid composition during lactation is important for body composition and glucose tolerance in the adult offspring.
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| 47. |
- Ušaj, Marko, et al.
(författare)
-
Electrofusion of B16-F1 and CHO cells: the comparison of the pulse first and contact first protocols
- 2013
-
Ingår i: Bioelectrochemistry. - : Elsevier BV. - 1567-5394 .- 1878-562X. ; 89, s. 34-41
-
Tidskriftsartikel (refereegranskat)abstract
- High voltage electric pulses induce permeabilisation (i.e. electroporation) of cell membranes. Electric pulses also induce fusion of cells which are in contact. Contacts between cells can be established before electroporation, in so-called contact first or after electroporation in pulse first protocol. The lowest fusion yield was obtained by pulse first protocol (0.8%±0.3%) and it was only detected by phase contrast microscopy. Higher fusion yield detected by fluorescence microscopy was obtained by contact first protocol. The highest fusion yield (15%) was obtained by modified adherence method whereas fusion yield obtained by dielectrophoresis was lower (4%). The results are in agreement with current understanding of electrofusion process and with existing electrochemical models. Our data indicate that probability of stalk formation leading to fusion pores and cytoplasmic mixing is higher in contact first protocol where cells in contact are exposed to electric pulses. Another contribution of present study is the comparison of two detection methods. Although fusion yield can be more precisely determined with fluorescence microscopy we should note that by using this detection method single coloured fused cells cannot be detected. Therefore low fusion yields are more reliably detected by phase contrast microscopy.
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| 48. |
- Mamontov, Eugen, 1955
(författare)
-
Homeorhesis and evolutionary properties of living systems: From ordinary differential equations to the active-particle generalized kinetics theory
- 2006
-
Ingår i: 10th Evolutionary Biology Meeting at Marseilles, 20-22 September 2006, Marseilles, France.
-
Konferensbidrag (refereegranskat)abstract
- Advanced generalized-kinetic-theory (GKT) models for biological systems are developed for populations of active (or living) particles [1]-[5]. These particles are described with both the stochastic variables common in kinetic theory (such as time, the particle random location and velocity) and the stochastic variables related to the internal states of an active particle. Evolution of these states represents biological, ecological, or social properties of the particle behavior. Paper [6] analyzes a number of the well-known statistical-mechanics approaches and shows that the active-particle GKT (APGKT) is the only treatment capable of modelling living systems. Work [2] summarizes the significance of the notion of an active particle in kinetic models. This notion draws attention to the features distinguishing living matter from nonliving matter. They are discussed by many authors (e.g., [7]-[15], [1]-[3], [6], [16]-[18]). Work [11] considers a lot of differences between living and nonliving matters, and the limitations of the modelling approaches developed for nonliving matter. Work [6] mainly focuses on the comparison of a few theoretical mechanics treatments in terms of the key living-matter properties formulated in [15]. One of the necessary properties of the evolution of living systems is homeorhesis. It is, loosely speaking, a peculiar qualitative and quantitative insensitivity of a living system to the exogenous signals acting on it. The earlier notion, homeostasis, was introduced by W. B. Cannon in 1926 who discussed the phenomenon in detail later [7]. Homeorhesis introduced by C. H. Waddington [8, p. 32] generalizes homeostasis and is well known in biology [8], [9], [12]. It is an inherent part of mathematical models for oncogeny (e.g., [16]-[18], [6, Appendix]). Homeorhesis is also discussed in [3, Section 4] in connection with APGKT. Homeorhesis is documented in ecology (e.g., [11], [13, the left column on p. 675]) where it is one of the key notions of the strong Gaia theory, a version of the Gaia theory (e.g., [14, Chapter 8]). The strong Gaia theory “states that the planet with its life, a single living system, is regulated in certain aspects by that life” [14, p. 124]. The very origin of the name “Gaia” is related to homeorhesis or homeostasis [14, p. 118]. These notions are also used in psychology and sociology. If evolution of a system is not homeorhetic, the system can not be living. Work [6, Appendix] derives a preliminary mathematical formulation of homeorhesis in terms of the simplest dynamical systems, i.e. ordinary differential equations (ODEs). The present work complements, extended, and further specify the approach of [6, Appendix]. The work comprises the two main parts. The first part develops the sufficient conditions for ODE systems to describe homeorhesis, and suggests a fairly general structure of the ODE model. It regards homeorhesis as piecewise homeostasis. The model can be specified in different ways depending on specific systems and specific purposes of the analysis. An example of the specification is also noted (the PhasTraM nonlinear reaction-diffusion model for hyperplastic oncogeny [16]-[18]). The second part of the work discusses implementation of the above homeorhesis ODE model in terms of a special version [3] of APGKT (see above). The key feature of this version is that the components of a living population need not be discrete: the subdivision into the components is described with a general, continuous-discrete probability distribution (see also [6]). This enables certain properties of living matter noted in [15]. Moreover, the corresponding APGKT model presents a system of, firstly, a generalized kinetic equation for the conditional distribution function conditioned by the internal states of the population and, secondly, Ito's stochastic differential equations for these states. This treatement employs the results on nonstationary invariant diffusion stochastic processes [19]. The second part of the work also stresses that APGKT is substantially more important for the living-matter analysis than in the case of nonliving matter. One of the reasons is certain limitations in experimental sampling of the living-system modes presented with stochastic processes. A few directions for future research are suggested as well. REFERENCES: [1] Bellomo, N., Bellouquid, A. and Delitala, M., 2004, Mathematical topics on the modelling complex multicellular systems and tumor immune cells competition, Math. Models Methods Appl. Sci., 14, 1683-1733. [2] Bellomo, N., 2006, New hot Paper Comments, Essential Science Indicators, http://www.esi-topics.com/nhp/2006 /may- 06-NicolaBellomo.html. [3] Willander, M., Mamontov, E. and Chiragwandi, Z., 2004, Modelling living fluids with the subdivision into the components in terms of probability distributions, Math. Models Methods Appl. Sci. 14, 1495-1520. [4] Bellomo, N. and Maini, P.K., 2005, Preface and the Special Issue “Multiscale Cancer Modelling-A New Frontier in Applied Mathematics”, Math. Models Methods Appl. Sci., 15, iii-viii. [5] De Angelis, E. and Delitala, M., 2006, Modelling complex systems in applied sciences: Methods and tools of the mathematical kinetic theory for active particles. Mathl Comput. Modelling, 43, 1310-1328. [6] Mamontov, E., Psiuk-Maksymowicz, K. and Koptioug, A., 2006, Stochastic mechanics in the context of the properties of living systems, Mathl Comput. Modelling, Article in Press, 13 pp. [7] Cannon, W.B., 1932, The Wisdom of the Body (New York: Norton). [8] Waddington, C.H., 1957, The Strategy of the Genes. A Discussion of Some Aspects of Theoretical Biology (London, George Allen and Unwin). [9] Waddington, C.H., 1968, Towards a theoretical biology, Nature, 218, 525-527. [10] Cotnoir, P.-A., 1981, La compétence environnementale: Une affaire d’adaptation. Séminaire en écologie behaviorale, Univeristé du Québec, Montralé. Available online at: http://pac.cam.org/culture.doc . [11] O’Neill, R.V., DeAngelis, D.L., Waide, J.B. and Allen, T.F.H., 1986, A Hierarchical Concept of Ecosystems, Princeton: Princeton Univ. Press). [12] Sauvant, D., 1992, La modélisation systémique en nutrition, Reprod. Nutr. Dev., 32, 217-230. [13] Christensen, N.L., Bartuska, A.M., Brown, J.H., Carpenter, S., D'Antonio, C., Francis, R., Franklin, J.F., MacMahon, J.A., Noss, R.F., Parsons, D.J., Peterson, C.H., Turner, M.G. and Woodmansee, R.G., 1996, The Report of the Ecological Society of America Committee on the Scientific Basis for Ecosystem Management, Ecological Applications, 6, 665-691. Available online at: http://www.esa.org/pao/esaPositions/Papers/ReportOfSBEM.php. [14] Margulis, L., 1998, Symbiotic Planet. A New Look at Evolution (Amherst: Sciencewriters). [15] Hartwell, L.H., Hopfield, J.J., Leibler, S. and Murray, A.W., 1999, From molecular to modular cell biology, Nature, 402, C47-C52. [16] Mamontov, E., Koptioug, A.V. and Psiuk-Maksymowicz, K., 2006, The minimal, phase-transition model for the cell- number maintenance by the hyperplasia-extended homeorhesis, Acta Biotheoretica, 54, 44 pp., (no. 2, May-June, accepted). [17] Psiuk-Maksymowicz, K. and Mamontov, E., 2005, The time-slices method for rapid solving the Cauchy problem for nonlinear reaction-diffusion equations in the competition of homeorhesis with genotoxically activated hyperplasia, In: European Conference on Mathematical and Theoretical Biology - ECMTB05 (July 18-22, 2005) Book of Abstracts, Vol.1 (Dresden: Center for Information Services and High Performance Computing, Dresden Univ. Technol.), p. 429 (http://www.ecmtb05.org/). [18] Psiuk-Maksymowicz, K. and Mamontov, E., 2006, The homeorhesis-based modelling and fast numerical analysis for oncogenic hyperplasia under radiation therapy, submitted. [19] Mamontov, E., 2005, Nonstationary invariant distributions and the hydrodynamic-style generalization of the Kolmogorov-forward/Fokker-Planck equation, Appl. Math. Lett. 18 (9) 976-982.
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| 49. |
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| 50. |
- Juul, Louise, et al.
(författare)
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Ulva fenestrata protein – comparison of three extraction methods with respect to protein yield and protein quality
- 2021
-
Ingår i: Algal Research. - : Elsevier BV. - 2211-9264. ; 60
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Tidskriftsartikel (refereegranskat)abstract
- Seaweed is gaining attention as a possible alternative and sustainable source of proteins. This study investigates three protein extraction methods and their effect on protein yield and quality when applied to Ulva fenestrata . Two of the methods included alkaline extractions (pH-shifts); one version solubilizing the proteins at pH 8.5 and one solubilizing them at pH 8.5 followed by pH 12 (pH 8.5+12). The third method was a mechanical pressing, using a double screw press. All extraction methods were followed by isoelectric precipitation to concentrate the proteins. Extraction at pH 8.5 gave the significantly highest total protein yield after the isoelectric precipitation, followed by extraction at pH 8.5+12 and lastly mechanical extraction gave the lowest yield. Proteins extracted with both alkaline methods had a significantly higher solubility at pH 7 and pH 9, compared to proteins from the mechanical pressing. There were no significant differences between the three methods in total D/L-amino acid ratio. Amino acid cross-links measured as lysinoalanine (LAL) and lanthionine (LAN) where found in significantly higher amounts in alkali-extracted proteins compared to mechanically extracted, however not to a degree that expect to compromise functional or nutritional quality. Further, no significant difference in protein in vitro digestibility was found between extraction methods. In conclusion, results indicated that protein extraction at pH 8.5 can be recommended, especially regarding total protein yield and solubility of the final protein extract.
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