| 1. |
- Wallensten, Anders, et al.
(författare)
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Surveillance of influenza A virus in migratory waterfowl in northern Europe
- 2007
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Ingår i: Emerging Infectious Diseases. - 1080-6040 .- 1080-6059. - 1080-6040 ; 13:3, s. 404-411
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Tidskriftsartikel (refereegranskat)abstract
- We conducted large-scale, systematic sampling of influenza type A virus in migratory waterfowl (mostly mallards [Anas platyrhynchos]) at Ottenby Bird Observatory, southeast Sweden. As with previous studies, we found a higher prevalence in fall than spring, and among juveniles compared with adults. However, in contrast to other studies, we found that prevalence in spring was sometimes high (mean 4.0%, highest 9.5%). This finding raises the possibility that ducks are capable of perpetuating influenza A virus of different subtypes and subtype combinations throughout the year and from 1 year to the next. Isolation of the H5 and H7 subtypes was common, which suggests risk for transmission to sensitive domestic animals such as poultry. We argue that wild bird screening can function as a sentinel system, and we give an example of how it could have been used to forecast a remote and deadly outbreak of influenza A in poultry.
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| 2. |
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| 3. |
- Henriksson, C., et al.
(författare)
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Knowledge and attitudes toward seeking medical care for AMI-symptoms
- 2009
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Ingår i: International Journal of Cardiology. - 1874-1754. ; 147:2, s. 224-227
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Time is crucial when an acute myocardial infarction (AMI) occurs, but patients often wait before seeking medical care. AIM: To investigate and compare patients' and relatives' knowledge of AMI, attitudes toward seeking medical care, and intended behaviour if AMI-symptoms occur. METHODS: The present study was a descriptive, multicentre study. Participants were AMI-patients
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| 4. |
- Karlsson, Per Erik, 1957, et al.
(författare)
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Risk assessments for forest trees: The performance of the ozone flux versus the AOT concepts
- 2007
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491. ; 146:3, s. 608-616
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Tidskriftsartikel (refereegranskat)abstract
- Published ozone exposure-response relationships from experimental studies with young trees performed at different sites across Europe were re-analysed in order to test the performance of ozone exposure indices based on AOTX (Accumulated exposure Over a Threshold of X nmol mol(-1)) and AF(st)Y (Accumulated Stomatal Flux above a threshold of Y nmol m(-2) s(-1)). AF(st)1.6 was superior, as compared to AOT40, for explaining biomass reductions, when ozone sensitive species with differing leaf morphology were included in the analysis, while this was not the case for less sensitive species. A re-analysis of data with young black cherry trees, subject to different irrigation regimes, indicated that leaf visible injuries were more strongly related to the estimated stomatal ozone uptake, as compared to the ozone concentration in the air. Experimental data with different clones of silver birch indicated that leaf thickness was also an important factor influencing the development of ozone induced leaf visible injury. (c) 2006 Elsevier Ltd. All rights reserved.
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| 5. |
- Björkman, Lena, 1965, et al.
(författare)
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Serum amyloid A mediates human neutrophil production of reactive oxygen species through a receptor independent of formyl peptide receptor like-1
- 2008
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Ingår i: Journal of Leukocyte Biology. - : Oxford University Press (OUP). - 0741-5400 .- 1938-3673. ; 83:2, s. 245-53
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Tidskriftsartikel (refereegranskat)abstract
- Serum amyloid A (SAA) is one of the acute-phase reactants, a group of plasma proteins that increases immensely in concentration during microbial infections and inflammatory conditions, and a close relationship between SAA levels and disease activity in rheumatoid arthritis (RA) has been observed. RA is an inflammatory disease, where neutrophils play important roles, and SAA is thought to participate in the inflammatory reaction by being a neutrophil chemoattractant and inducer of proinflammatory cytokines. The biological effects of SAA are reportedly mediated mainly through formyl peptide receptor like-1 (FPRL1), a G protein-coupled receptor (GPCR) belonging to the formyl peptide receptor family. Here, we confirmed the affinity of SAA for FPRL1 by showing that stably transfected HL-60 cells expressing FPRL1 were activated by SAA and that the response was inhibited by the use of the FPRL1-specific antagonist WRWWWW (WRW4). We also show that SAA activates the neutrophil NADPH-oxidase and that a reserve pool of receptors is present in storage organelles mobilized by priming agents such as TNF-alpha and LPS from Gram-negative bacteria. The induced activity was inhibited by pertussis toxin, indicating the involvement of a GPCR. However, based on FPRL1-specific desensitization and use of FPRL1 antagonist WRW4, we found the SAA-mediated effects in neutrophils to be independent of FPRL1. Based on these findings, we conclude that SAA signaling in neutrophils is mediated through a GPCR, distinct from FPRL1. Future identification and characterization of the SAA receptor could lead to development of novel, therapeutic targets for treatment of RA.
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| 6. |
- Holmgren, Christina M, et al.
(författare)
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Presumed arrhythmic death in consecutive survivors of acute myocardial infarction--implications for primary implantable cardioverter defibrillator implantation.
- 2009
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Ingår i: Coronary artery disease. - : Lippincott Williams & Wilkins. - 1473-5830 .- 0954-6928. ; 20:2, s. 155-62
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Tidskriftsartikel (refereegranskat)abstract
- AIM: To describe the occurrence of arrhythmic death among survivors of acute myocardial infarction (AMI) and the availability of a primary implantable cardioverter defibrillator (ICD). METHODS: Consecutive patients who fulfilled the criteria for AMI admitted to the Sahlgrenska University Hospital during 21 months were prospectively followed for 2 years with a focus on echocardiography and mode of death. RESULTS: Among the 471 patients, for whom information on ejection fraction (EF) was available and who survived the first week, 10 patients died between days 7 and 30 - of whom one had an arrhythmic death. Among the 461 survivors on day 30, 34 patients (7.4%) had an EF of 30% or less. Among these, 24 were judged to be available for ICD implantation, of whom one died an arrhythmic death during follow-up. Among the remaining 10 patients who were excluded from ICD indication because of either high age and/or severe comorbidity, two patients died an arrhythmic death. Among the remaining 427 patients who had an EF greater than 30%, six died an arrhythmic death. Thus, 10 patients, with EF assessed, died an arrhythmic death between day 7 and 2 years after AMI, but only one would have received an ICD according to the Multicenter Automatic Defibrillator Implantation Trial II criteria and clinical judgement. CONCLUSION: Of the 471 consecutive survivors of AMI, 10 (2%) died an arrhythmic death, of whom only one would have received an ICD according to current guidelines and clinical judgement. Predictors of subsequent arrhythmic death after an AMI, useful on a per patient basis, remain an unmet need.
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| 7. |
- Nicholls, Ian A., et al.
(författare)
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Theoretical and Computational Strategies for Rational Molecularly Imprinted Polymer Design
- 2009
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Ingår i: Biosensors & bioelectronics. - : Elsevier BV. - 0956-5663 .- 1873-4235. ; 25:3, s. 543-552
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Tidskriftsartikel (refereegranskat)abstract
- The further evolution of molecularly imprinted polymer science and technology necessitates the development of robust predictive tools capable of handling the complexity of molecular imprinting systems. A combination of the rapid growth in computer power over the past decade and significant software developments have opened new possibilities for simulating aspects of the complex molecular imprinting process. We present here a survey of the current status of the use of in silico-based approaches to aspects of molecular imprinting. Finally, we highlight areas where ongoing and future efforts should yield information critical to our understanding of the underlying mechanisms sufficient to permit the rational design of molecularly imprinted polymers.
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| 8. |
- Svensson, L., et al.
(författare)
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Comparison of very early treatment with either fibrinolysis or percutaneous coronary intervention facilitated with abciximab with respect to ST recovery and infarct-related artery epicardial flow in patients with acute ST-segment elevation myocardial infarction: the Swedish Early Decision (SWEDES) reperfusion trial
- 2006
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Ingår i: Am Heart J. - : Mosby, Inc.. - 1097-6744 .- 0002-8703. ; 151:4
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Results from a number of studies indicate that primary percutaneous coronary intervention (PCI) is superior to fibrinolysis for treatment of acute ST-elevation myocardial infarction. Modern adjunctive antithrombotic treatment with systematic use of low-molecular-weight heparins, fibrin-specific thrombolysis, and glycoprotein IIb/IIIa receptor inhibitors may improve the outcome compared with what was achieved in previous studies. METHODS: Patients with ST-elevation myocardial infarction were randomized to receive enoxaparin followed by reteplase (group A; n = 104) or enoxaparin followed by abciximab and transfer to invasive center for optional PCI (group B; n = 101). Primary end points were ST-segment resolution 120 minutes and TIMI flow at coronary angiography 5 to 7 days after randomization. RESULTS: Forty-two percent of the patients started therapy in the prehospital phase. Time from symptom to treatment was 114 minutes in group A and 202 minutes in group B. Baseline characteristics were similar in the 2 groups. Sixty-four percent in group A and 68% in group B had ST resolution of > 50% at 120 minutes (not significant). At control angiography, 54% in the fibrinolytic group and 71% in the invasive group had TIMI 3 flow (P = .04). At 30 days, the composite of death, stroke, or reinfarction occurred in 8% in the fibrinolytic group compared with 3% in the invasive group (not significant). CONCLUSIONS: Despite much shorter time delay to start of fibrinolysis than PCI, this did not result in signs of superior myocardial reperfusion. Epicardial flow in the infarct-related artery was better after invasive therapy, and there was a trend toward better clinical outcome after this treatment compared with after fibrinolysis.
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| 9. |
- Ahlin, Gustav, et al.
(författare)
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Structural requirements for drug inhibition of the liver specific human organic cation transport protein 1
- 2008
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Ingår i: Journal of Medicinal Chemistry. - : American Chemical Society (ACS). - 0022-2623 .- 1520-4804. ; 51:19, s. 5932-5942
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Tidskriftsartikel (refereegranskat)abstract
- The liver-specific organic cation transport protein (OCT1; SLC22A1) transports several cationic drugs including the antidiabetic drug metformin and the anticancer agents oxaliplatin and imatinib. In this study, we explored the chemical space of registered oral drugs with the aim of studying the inhibition pattern of OCT1 and of developing predictive computational models of OCT1 inhibition. In total, 191 structurally diverse compounds were examined in HEK293-OCT1 cells. The assay identified 47 novel inhibitors and confirmed 15 previously known inhibitors. The enrichment of OCT1 inhibitors was seen in several drug classes including antidepressants. High lipophilicity and a positive net charge were found to be the key physicochemical properties for OCT1 inhibition, whereas a high molecular dipole moment and many hydrogen bonds were negatively correlated to OCT1 inhibition. The data were used to generate OPLS-DA models for OCT1 inhibitors; the final model correctly predicted 82% of the inhibitors and 88% of the noninhibitors of the test set.
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| 10. |
- Andersson, Bodil, et al.
(författare)
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Combining Keystroke Logging with Eye Tracking
- 2006
-
Ingår i: Writing and Digital Media. - 1572-6304. - 0080448631 ; 17, s. 166-172
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Bokkapitel (refereegranskat)abstract
- This chapter describes the successful development of a new methodology for studying on-line writing. The text-logging tool ScriptLog has been combined with the eyetracking technology iView X HED HT, in order to enhance the study of the interplay between writing, monitoring and revision. Data on the distribution of visual attention during writing help determining to what extent pauses are used for monitoring. The complexity of the experimental settings, and the expertise needed for interpreting the eye-tracking data make this a method suitable mainly for laboratory settings. The chapter also introduces an analysis tool that merges data from ScriptLog and iView and thus helps the researcher to organise and analyse the vast amount of data produced.
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| 11. |
- Bergfeldt, Erik, et al.
(författare)
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A Performance Study of Bandwidth Measurement Tools over Mobile Connections
- 2009
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Ingår i: 2009 IEEE 69th Vehicular Technology Conference Spring. - : IEEE. - 9781424425174 ; , s. 2978-2982
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Konferensbidrag (refereegranskat)abstract
- The knowledge of the present available bandwidth on a network path is essential in numerous contexts, such as network management and streaming applications. A network path nowadays often contains at least one wireless link. This is obviously true for mobile users having a wireless connection to the Internet through a laptop or mobile terminal. The existing tools for measuring end-to-end available bandwidth are developed and optimized for paths with only guided media links. Since the characteristics for wired links and radio links differ in many aspects, such as fluctuations in capacity and stability, the network tools need to be evaluated also for network paths containing wireless links. In this investigation we have performed experiments over a high-speed downlink UMTS channel. This makes the present paper unique in the sense that it evaluates and analyzes the applicability of available-bandwidth measurement tools over a radio interface in a wide-area mobile communication network. For the experiments, a commercial mobile network has been used. The measurements show that it is feasible to achieve reliable estimates under certain circumstances. However, some cases pose challenges which motivate further studies.
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| 12. |
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| 13. |
- Bergfeldt, Erik, et al.
(författare)
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Real-time available-bandwidth estimation using filtering and change detection
- 2009
-
Ingår i: Computer Networks. - : Elsevier. - 1389-1286. ; 53:15, s. 2617-2645
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a filter-based method BART (Bandwidth Available in Real-Time) for real-time estimation of end-to-end available bandwidth in packet-switched communication networks. BART relies on self-induced congestion, and repeatedly samples the available bandwidth of the network path with sequences of probe-packet pairs. The method is light-weight with respect to computation and memory requirements, and performs well when only a small amount of probe traffic is injected. BART uses Kalman filtering, which enables real-time estimation. It maintains a current estimate, which is incrementally improved with each new measurement of the inter-packet time separation in a sequence of probe-packet pairs. It is possible to tune BART according to specific needs. The estimation performance can be significantly enhanced by employing a change-detection technique. An implementation of BART has been evaluated in a physical test network with carefully controlled cross traffic. In addition, experiments have been performed over the Internet as well as over a mobile broadband connection. © 2009 Elsevier B.V. All rights reserved.
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| 14. |
- Eklund, Patrik, et al.
(författare)
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Categorical innovations for rough sets
- 2009
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Ingår i: Rough set theory. - Berlin/Heidelberg : Springer Berlin/Heidelberg. - 9783540899204 - 9783540899211 ; , s. 45-69
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Categories arise in mathematics and appear frequently in computer science where algebraic and logical notions have powerful representations using categorical constructions. In this chapter we lean towards the functorial view involving natural transformations and monads. Functors extendable to monads, further incorporating order structure related to the underlying functor, turn out to be very useful when presenting rough sets beyond relational structures in the usual sense. Relations can be generalized with rough set operators largely maintaining power and properties. In this chapter we set forward our required categorical tools and we show how rough sets and indeed a theory of rough monads can be developed. These rough monads reveal some canonic structures, and are further shown to be useful in real applications as well. Information within pharmacological treatment can be structured by rough set approaches. In particular, situations involving management of drug interactions and medical diagnosis can be described and formalized using rough monads.
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| 15. |
- Eklund, Patrik, 1958-, et al.
(författare)
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Computational coronary artery bypass grafting
- 2005
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Ingår i: Sixth International Conference on Computational Intelligence and Multimedia Applications, 2005.. - : IEEE Computer Society. - 0769523587 ; , s. 138-144
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Konferensbidrag (refereegranskat)abstract
- Multimedia in health care is a topic of growing interest. Guideline presentation, utility and adherence require intelligence and multimedia to interact in decision support environments. In this paper we aim at identifying guideline logic during statistical analysis. The case study is drawn from a regional perspective on analysis and production of data, information and knowledge.
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| 16. |
- Eklund, Patrik, et al.
(författare)
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Rough monadic interpretations of pharmacologic information
- 2007
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Ingår i: ICCS 2007. - London : Springer. - 9781846289903 - 9781846289927 ; , s. 108-113
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Konferensbidrag (refereegranskat)abstract
- Public databases for pharmacological information provide rich and complete information for therapeutic requirements. In particular, the ATe code with its unique identification of drug compound is the basis e.g. of modelling of drug interactions. Therapeutic decisions are frequently faced with needs to consider not just drug-drug interactions but also drugs interacting with sets of drugs and even sets of medical conditions. The typing of interactions provides an additional complication as this is an entrance towards management of uncertainties concerning interactions. The hierarchical structure of pharmacological information and its intrinsic uncertainties are in this paper used as an information platformfor the demonstration of the power of rough set modelling. Rough sets in a more general functorial view involving partially ordered monads are able to capture interactionswith respect to different granularities in the information hierarchy.
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| 17. |
- Gottfridsson, Christer, 1958, et al.
(författare)
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Sex difference and factors associated with outcome in patients with sustained ventricular arrhythmias.
- 2008
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Ingår i: Scandinavian cardiovascular journal : SCJ. - : Informa UK Limited. - 1401-7431 .- 1651-2006. ; 42:3, s. 182-91
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To describe gender differences and factors of importance for outcome in patients referred for sustained ventricular arrhythmias. RESULTS: Two hundred and fifty three patients took part in the survey, 126 (20 women) had sustained monomorphic ventricular tachycardia (VT) and 127 (31 women) had polymorphic VT/ventricular fibrillation. Ischemic heart disease was less common in women than in men (47 vs. 80%). At discharge, an ICD implant was similarly common in women (33%) and men (29%). One hundred and twenty five (65%) men and 37 (79%) women were alive at follow-up, p =0.08 (median follow-up 53 months). Independent predictors of long-term mortality were: 1) PVT/VF as the presenting arrhythmia, 2) a low ejection fraction, 3) increased QRS duration and 4) diabetes mellitus. CONCLUSION: The lower proportion of women compared to men being referred for evaluation of sustained ventricular arrhythmias may contribute to the lower number of ICD implants in women. The long-term survival in women and men did not differ significantly.
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| 18. |
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| 19. |
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| 20. |
- Gundlegård, David, 1978-, et al.
(författare)
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Generating Road Traffic Information from Cellular Networks - New Possibilities in UMTS
- 2006
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Ingår i: Proceedings 2006 6th International Conference onITS Telecommunications. - 0780395875 - 0780395875 ; , s. 1128-1133
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Konferensbidrag (refereegranskat)abstract
- This paper summarizes different approaches to collecting road traffic information from second-generation cellular systems (GSM) and point out the possibilities that arise when third generation systems (UMTS) are used. Cell breathing is a potential problem, but smaller cells, soft handover and flexible measurements have the potential to increase the usage area and information quality when road traffic information is extracted from the UMTS network compared to using the GSM network
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| 21. |
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| 22. |
- Gundlegård, David, et al.
(författare)
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Handover location accuracy for travel time estimation in GSM and UMTS
- 2009
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Ingår i: IET Intelligent Transport Systems. - : Institution of Engineering and Technology (IET). - 1751-956X .- 1751-9578. ; 3:1, s. 87-94
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Tidskriftsartikel (refereegranskat)abstract
- Field measurements from the GSM and UMTS networks are analysed in a road traffic information context. The measurements indicate a potentially large improvement using UMTS signalling data compared with GSM regarding handover location accuracy. These improvements can be used to generate real-time traffic information with higher quality and extend the geographic usage area for cellular-based travel time estimation systems. The results con. rm previous reports indicating that the technology has a large potential in GSM and also show that the potential might be even larger and more. exible using UMTS. Assuming that non-vehicle terminals can be. ltered out, that vehicles are tracked to the correct route and that handovers can be predicted correctly, a conclusion from the experiments is that the handover location accuracy in both GSM and UMTS will be sufficient to estimate useful travel times, also in urban environments. In a real system, these tasks are typically very challenging, especially in an urban environment. Further, it is reasonably established that the location error will be minor for the data obtained from UMTS.
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| 23. |
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| 24. |
- Gundlegård, David, et al.
(författare)
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Road Traffic Estimation using Cellular Network Signaling in Intelligent Transportation Systems
- 2009
-
Ingår i: Wireless technologies in Intelligent Transportation Systems. - Hauppauge, NY : Nova Science Publishers. - 9781607415886 - 1607415887 ; , s. 1-33
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- In the area of Intelligent Transportation Systems the introduction of wireless communications is reshaping the information distribution concept, and is one of the most important enabling technologies. The distribution of real-time traffic information, scheduling and route-guidance information is helping the transportation management systems in their strive to optimize the system. The communication required to transfer all this information is rather expensive in terms of transmission power, use of the scarce resources of frequencies and also the building of an infrastructure to support the transceivers. By using information that already exists and is exchanged within the infrastructures of the GSM and UMTS networks, a lot of the resource problems are solved. The information that could be extracted from these cellular networks could be used to obtain accurate road traffic information to support real-time traffic information. In this way the cellular networks not only becomes the means to distribute information but also a source of road traffic information.From the analysis made it is obvious that the potential of retrieving valuable road traffic information from cellular systems in a cost efficient way, i.e. by using already existing signalling data, is very high. It has however not been clear what to expect from these systems in terms of accuracy, availability and coverage. In this chapter the basics for this is laid out and discussed in detail. A practical trial has also been performed and the results show clearly the potential as well as the differences in using the GSM compared to the UMTS system. The advantages and drawbacks are discussed and backed up by real measurements from an existing road segment environment. The main advantages of using the existing signalling data, i.e., passive monitoring compared to active monitoring where the terminal sends extra data is discussed and could be summarized in three components, no user acceptance is necessary, no extra signalling is necessary and it does not drain the terminal battery.In the future it is likely that vehicles need to communicate more frequently with each other and with some kind of traffic control centre. This traffic will also be very useful in order to estimate road traffic information using the signalling information obtained from the cellular system. However, the enhanced communication systems will also change traffic patterns in the cellular networks which will affect the potential of estimating road traffic from cellular systems. The evolvement indicates that the terminals will be in active state almost constantly, and hence the updating information will be more frequent and the information more accurate.
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| 25. |
- Gundlegård, David, et al.
(författare)
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Route Classification in Travel Time Estimation Based on Cellular Network Signaling
- 2009
-
Ingår i: Proceedings of 12th International IEEE Conference on Intelligent Transport Systems (ITSC), October 3-7, St. Louis, USA. - 9781424455201 - 9781424455195 ; , s. 474-479
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Konferensbidrag (refereegranskat)abstract
- Travel time estimation based on cellular network signaling is a promising technology for delivery of wide area travel times in real-time. The technology has received much attention recently, but few academic research reports has so far been published in the area, which together with uncertain location estimates and environmental dependent performance makes it difficult to assess the potential of the technology. This paper aims to investigate the route classification task in a cellular travel time estimation context in detail. In order to estimate the magnitude of the problem, two classification algorithms are developed, one based on nearest neighbor classification and one based on Bayesian classification. These are then evaluated using field measurements from the GSM network. A conclusion from the results is that the route classification problem is not trivial even in a highway environment, due to effects of multipath propagation and changing radio environment. In a highway environment the classification problem can be solved rather efficiently using e.g., one of the methods described in this paper, keeping the effect on travel time accuracy low. However, in order to solve the route classification task in urban environments more research is required.
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| 26. |
- Hartikainen, Erik, 1977-, et al.
(författare)
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Adjustment of the BART Kalman Filter to Improve Real-Time Estimation of End-to-End Available Bandwidth
- 2005
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Ingår i: Proceedings of SNCNW 2005. - Sweden : SNCNW. ; , s. 56-
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Konferensbidrag (refereegranskat)abstract
- This paper concerns simulation results using the network simulator ns-2 to validate the end-to-end available bandwidth estimation ability of the real-time measurement tool BART (Bandwidth Available in Real-Time). In addition to an active probing scheme, this method applies Kalman filtering in order to produce available bandwidth estimates. Simulation results show that clever use of an adjustable filter parameter yields great possibilities of achieving highly accurate estimates, even in the presence of harsh circumstances.
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| 27. |
- Hartikainen, Erik, 1977-, et al.
(författare)
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Change Detection and Estimation for Network-Measurement Applications
- 2007
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Ingår i: Proceedings of the 2nd ACM workshop on Performance monitoring and measurement of heterogeneous wireless and wired networks. - New York, NY, USA : ACM Digital Library. - 9781595938053 ; , s. 1-10
-
Konferensbidrag (refereegranskat)abstract
- This paper presents a method for improving filter-based network-state estimation by adding detection and estimation of sudden changes in the system state. This can be of benefit in various contexts, e.g. in network management and adaptive streaming applications. In particular, it is shown that the performance of available-bandwidth estimation can be significantly enhanced by employing change detection in conjunction with a filter-based estimator. The use of filtering makes it feasible to track the communication network state and to estimate selected properties in real-time. In addition, filter-based methods may be combined with change detection in order to overcome the trade-off regarding stable estimation versus speed of adaptation to change. We discuss filtering and change detection in general, and present the novel approach of combining the filter-based available-bandwidth estimator BART with the Generalized Likelihood Ratio (GLR) change-detection test, which estimates both the time and magnitude of changes.
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| 28. |
- Herlitz, Johan, et al.
(författare)
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Långtidsprognos vid hjärtinfarkt sämre än väntat
- 2008
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Ingår i: Läkartidningen. - : Läkartidningen förlag AB. - 0023-7205 .- 1652-7518. ; 105:17, s. 1289-1294
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Tidskriftsartikel (refereegranskat)abstract
- I en representativ population patienter som sjukhusvårdats i Göteborgs kommun med slutdiagnos akut hjärtinfarkt (medelålder 75 år) var långtidsprognosen mer alarmerande än vad som tidigare rapporterats i litteraturen. Under det första året efter symtomdebut hade 30 procent avlidit, och under de första 3 åren hade 45 procent avlidit. Endast 60 procent av patienterna behandlades på hjärtinfarktavdelning. Högriskgrupper var de patienter som aldrig behandlades på hjärtinfarktavdelning och de patienter där det inte förelåg någon misstanke om hjärtinfarkt vid ankomst till sjukhus.
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| 29. |
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| 30. |
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| 31. |
- Johansson, M. K., et al.
(författare)
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Hematopoietic stem cell-targeted neonatal gene therapy reverses lethally progressive osteopetrosis in oc/oc mice
- 2007
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 109:12, s. 5178-85
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Tidskriftsartikel (refereegranskat)abstract
- Infantile malignant osteopetrosis (IMO) is a fatal disease caused by lack of functional osteoclasts, and the only available treatment is hematopoietic stem cell (HSC) transplantation. In the majority of patients, the TCIRG1 gene, coding for a subunit of a proton pump essential for bone resorption, is mutated. Oc/oc mice have a deletion in the homologue gene (tcirg1) and die at 3 to 4 weeks, but can be rescued by neonatal transplantation of HSCs. Here, HSC-targeted gene therapy of osteopetrosis in the oc/oc mouse model was developed. Oc/oc fetal liver cells depleted of Ter119-expressing erythroid cells were transduced with a retroviral vector expressing tcirg1 and GFP, and subsequently transplanted intraperitoneally to irradiated neonatal oc/oc mice. Eight of 15 mice survived past the normal life span of oc/oc mice. In vitro osteoclastogenesis revealed formation of GFP-positive osteoclasts and bone resorption, albeit at a lower level than from wild-type cells. The skeletal phenotype was analyzed by X-ray and histopathology and showed partial correction at 8 weeks and almost normalization after 18 weeks. In summary, osteopetrosis in oc/oc mice can be reversed by neonatal transplantation of gene-modified HSCs leading to long-term survival. This represents a significant step toward the development of gene therapy for osteopetrosis.
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| 32. |
- Johansson, M., et al.
(författare)
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Neonatal hematopoietic stem cell transplantation cures oc/oc mice from osteopetrosis
- 2006
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Ingår i: Exp Hematol. - : Elsevier BV. - 0301-472X .- 1873-2399. ; 34:2, s. 242-9
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Infantile malignant osteopetrosis (IMO) is a rare autosomal recessive disorder affecting osteoclast function. Fifty percent of the patients have a mutation in the TCIRG1 gene coding for one subunit of an osteoclast proton pump. The only curative treatment is hematopoietic stem cell transplantation (SCT). The oc/oc mouse has a mutation in the gene homologous to TCIRG1 and its expected lifespan is only 3 to 4 weeks. Previous attempts to cure these mice with SCT have been unsuccessful. We wanted to determine if early hematopoietic SCT using enriched and MHC-matched stem cells can cure oc/oc mice from osteopetrosis. METHODS: One- and 8-day-old oc/oc and control mice were radiated with 200, 400, or 600 cGy and transplanted intraperitoneally with 1 or 5 x 10(6) normal lineage-depleted bone marrow cells. Blood, x-ray, and pathology analyses were performed on transplanted mice. RESULTS: All 1-day-old mice irradiated with 400 cGy and transplanted with 5 x 10(6) cells survived long term. An engraftment level of 20% is sufficient to correct most features of the disease. X-ray and histopathology examination of transplanted animals showed normalization of bone structure. However, although a correction of bone structure occurred, the transplanted oc/oc mice were smaller in size than their littermates. In contrast to untreated animals, oc/oc mice developed teeth after transplantation, but with abnormal structure and shape making them unusable. CONCLUSION: We have shown that this murine form of IMO is curable with neonatal SCT using enriched stem cells.
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| 33. |
- Karlsson, Johan M, et al.
(författare)
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Hierarchical Structure of Wireless Systems - an Analytical Performance Study
- 2008
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Ingår i: 2008 Ieee 19Th International Symposium On Personal, Indoor And Mobile Radio Communications. ; , s. 2509-2514
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Konferensbidrag (refereegranskat)abstract
- Sammanfattning-The use of hierarchical structures for providing excellent wireless connections for customers has attained growing attention. Models to investigate the QoS requirements rather quickly become complicated and hard to analyze. In the paper a first rough analytical approach for the answer is given. As the users devote more and more time to be connected through wireless connections, and at the same time becomes more and more mobile the traditional systems does not work. Our model is based on a hierarchical structure where different, already existing, wireless systems interact to maintain coverage for moving customers outdoors as well as indoors. The QoS requirements are based on the type of service used and the mobility pattern. The system should be able to configure the connection to make the optimal choice among those networks present at the location of the customer. Further, the mobile terminals must be able to handle the different networks. In a general case, systems with broader coverage and usually lower bandwidth will act as backup systems for higher quality systems. Our analytical tool shows the benefits and drawbacks of such a system. The transition duration times between usage of different systems are analyzed together with their variance and squared coefficient of variation. Each handover is a source for failure. By changing the parameter setting it is possible to get at better understanding of how to configure hierarchical wireless systems for best performance. With the presented formulas this could be achieved in a fast and thorough way.
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| 34. |
- Karlsson, Johan M
(författare)
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Kontinuerliga självvalda kontroller under kursgång
- 2006
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Ingår i: [Host publication title missing].
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Konferensbidrag (refereegranskat)abstract
- Målet med att införa kontinuerliga självvalda kontroller under en kurs gång är att på så vis engagera och motivera studenterna att läsa kontinuerligt redan från kursstart. De självvalda kontrollerna genomförs individuellt under kursen för att fånga upp vilka kunskaper som studenten införskaffat hitintills. Ett bra resultat på dessa självvalda kontroller innebär att studenten erhåller bonuspoäng vilka kan tillgodoräknas mot resultatet på tentamen. Rapporten diskuterar funktionen och resultatet av införandet av dessa självvalda kontroller. Resultaten visar att en större andel av dem som genomför de självvalda kontrollerna också klarar den slutliga tentamen. Vidare är en stor del av studenterna hjälpta av de bonuspoäng de uppnår på de självvalda kontrollerna för att uppnå ett högre betyg. Uppfattningen är att även då delvis flervalsfrågor används studenterna uppnår en större förståelse för ämnet. Studenterna är nöjda med införandet av detta nya moment i kursen. Sammantaget indikerar slutligen detta att verksamheten bör vara fortvarig vid kommande kurser.
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| 35. |
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| 36. |
- Lindkvist, Annica, et al.
(författare)
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Reduction of the HIV-1 reservoir in resting CD4+ T-lymphocytes by high dosage intravenous immunoglobulin treatment: a proof-of-concept study
- 2009
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Ingår i: AIDS research and therapy. - : Springer Science and Business Media LLC. - 1742-6405. ; 6:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The latency of HIV-1 in resting CD4+ T-lymphocytes constitutes a major obstacle for the eradication of virus in patients on antiretroviral therapy (ART). As yet, no approach to reduce this viral reservoir has proven effective. METHODS: Nine subjects on effective ART were included in the study and treated with high dosage intravenous immunoglobulin (IVIG) for five consecutive days. Seven of those had detectable levels of replication-competent virus in the latent reservoir and were thus possible to evaluate. Highly purified resting memory CD4+ T-cells were activated and cells containing replication-competent HIV-1 were quantified. HIV-1 from plasma and activated memory CD4+ T-cells were compared with single genome sequencing (SGS) of the gag region. T-lymphocyte activation markers and serum interleukins were measured. RESULTS: The latent HIV-1 pool decreased with in median 68% after IVIG was added to effective ART. The reservoir decreased in five, whereas no decrease was found in two subjects with detectable virus. Plasma HIV-1 RNA >or= 2 copies/mL was detected in five of seven subjects at baseline, but in only one at follow-up after 8-12 weeks. The decrease of the latent HIV-1 pool and the residual plasma viremia was preceded by a transitory low-level increase in plasma HIV-1 RNA and serum interleukin 7 (IL-7) levels, and followed by an expansion of T regulatory cells. The magnitude of the viral increase in plasma correlated to the size of the latent HIV-1 pool and SGS of the gag region showed that viral clones from plasma clustered together with virus from activated memory T-cells, pointing to the latent reservoir as the source of HIV-1 RNA in plasma. CONCLUSION: The findings from this uncontrolled proof-of-concept study suggest that the reservoir became accessible by IVIG treatment through activation of HIV-1 gene expression in latently-infected resting CD4+ T-cells. We propose that IVIG should be further evaluated as an adjuvant to effective ART.
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| 37. |
- Omland, Torbjörn, et al.
(författare)
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Circulating osteoprotegerin levels and long-term prognosis in patients with acute coronary syndromes.
- 2008
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Ingår i: Journal of the American College of Cardiology. - : Elsevier BV. - 1558-3597 .- 0735-1097. ; 51:6, s. 627-33
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: This study was designed to assess the association between osteoprotegerin (OPG) levels on admission and long-term prognosis in patients with acute coronary syndromes (ACS). BACKGROUND: Osteoprotegerin, a member of the tumor necrosis factor receptor superfamily, has pleiotropic effects on bone metabolism, endocrine function, and the immune system. METHODS: Serum samples for OPG analysis were obtained within 24 h of admission in 897 ACS patients (median age 66 years, 71% men) and related to the incidence of death, heart failure (HF) hospitalizations, myocardial infarction (MI), and stroke. RESULTS: A total of 261 patients died during a median follow-up of 89 months. The baseline OPG concentration was strongly associated with increased long-term mortality (hazard ratio [HR] for HR per 1 SD increase in logarithmically transformed OPG level 1.7 [range 1.5 to 1.9] p < 0.0001) and HF hospitalizations (HR 2.0 [range 1.6 to 2.5]; p < 0.0001) but weaker with recurrent MI (HR 1.3 [range 1.0 to 1.5]; p = 0.02) and not with stroke (HR 1.2 [range 0.9 to 1.6]; p = 0.35). After adjustment for conventional risk markers, including troponin I, C-reactive protein (CRP), B-type natriuretic peptide (BNP), and ejection fraction, the association remained significant for mortality (HR 1.4 [range 1.2 to 1.7]; p < 0.0001) and HF hospitalization (HR 1.6 [range 1.2 to 2.1]; p = 0.0002), but not recurrent MI. By comparison of the area under the receiver-operating characteristics curves, OPG performed similarly to BNP and ejection fraction and significantly better than CRP and troponin I as a predictor of death. CONCLUSIONS: Serum OPG is strongly predictive of long-term mortality and HF development in patients with ACS, independent of conventional risk markers.
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| 38. |
- Persson, Henrik, et al.
(författare)
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Evaluation of Inter-System Handover Frequency in a Hierarchical Structure
- 2009
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Ingår i: 2009 Global Mobile Congress. ; , s. 441-445
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Konferensbidrag (refereegranskat)abstract
- Mobile terminals that have the possibility to make intersystem handovers will increase in numbers and importance as the interaction between wireless networks evolve. New services and applications are pushing this system development. Users want their mobile terminal to be able to make seamless handovers both within the present wireless network as well as to other wireless systems. In this paper such a mobile terminal is foreseen and its system utilization applied in a three level hierarchical structure of wireless systems is presented and analyzed. The intersystem handovers between the three different levels (systems) are investigated for different settings of for example overlap and load. The implementation of new services in the systems effect on the performance is analyzed while altering the proposed scenarios. The handover rates and blocking probabilities are discussed and thoroughly explained. Further, the mean number of handovers per connection is investigated.
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| 39. |
- Persson, Henrik, et al.
(författare)
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Inter-system handover on a cellular level in a hierarchical structure
- 2008
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Ingår i: ICOIN 2008: International Conference on Information Networking. - 9788996076117 ; , s. 297-301
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Konferensbidrag (refereegranskat)abstract
- Within this paper a simulation model of a hierarchical structure with three levels with different wireless systems is presented and investigated. The analysis is placed on a cellular level to better understand the user behavior. Modeled is a city environment, where the focus is made on the inter-system handovers between the different wireless systems and how they are affected by the change of different parameters. The results show that inter-system handovers will react differently dependent on what type of handover that is investigated. The results can be used to analyze the influence of mobility, as well as service demands. This can be an effective way to dimensioning cooperating wireless systems and to analyze the effect of introducing a new service or application.
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| 40. |
- Zander, Roland, et al.
(författare)
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Analysis of dynamic reservation schemes for cellular networks
- 2006
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Ingår i: World Wireless Congress. - 1558-7835. ; 2006, s. 349-354
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Konferensbidrag (refereegranskat)abstract
- Out of Quality of Service reasons, higher priority shall in cellular networks be assigned to ongoing connections than to new call attempts. In order to improve the efficiency of the bandwidth reservation scheme, the amount of bandwidth to reserve for high priority connections can be made time-varying and adaptive towards the momentary network conditions. Subscriber movement predictions can be applied to obtain handover arrival rate estimations, which can be used as input to the bandwidth reservation allocation procedure. The subscribers can for instance be grouped according to speed and previous cells. In this paper, a Markovian analysis of such prediction-oriented grouping features will be performed. The obtained analytical results will be validated using computer simulations.
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| 41. |
- Zander, Roland, et al.
(författare)
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Analysis of prediction-oriented features in dynamic bandwidth reservation schemes
- 2006
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Ingår i: IEEE Vehicular Technology Conference. - 1550-2252. ; , s. 2439-2443
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Konferensbidrag (refereegranskat)abstract
- Out of Quality of Service reasons, higher priority shall in cellular networks be assigned to ongoing connections than to new call attempts. This can be accomplished through reserving a portion of the bandwidth assigned to a cell exclusively for high priority connections. A low priority call is only admitted to a cell if the unoccupied bandwidth in the cell following the acceptance of the call exceeds or is equal to the reserved bandwidth. In order to improve the efficiency of the bandwidth reservation scheme, the amount of bandwidth to reserve can be made time-varying and adaptive towards the momentary network conditions. Subscriber movement predictions can be applied to obtain handover arrival rate estimations, which can be used as input to the bandwidth reservation allocation procedure. The subscribers can for instance be grouped according to speed and previous cells. In this paper, a Markovian analysis of such prediction-oriented grouping features will be performed. The probability for a new call attempt to be blocked and the probability for a handover attempt to fail, due to channel occupancies, will be calculated for a bandwidth reservation scheme with and without grouping features. The obtained analytical results will be validated using computer simulations. © 2006 IEEE.
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| 42. |
- Zander, Roland, et al.
(författare)
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Performance analysis of cell zone partitioning in bandwidth reservation schemes
- 2005
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Ingår i: Proceedings - 6th World Wireless Congress, WWC. ; , s. 272-277
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Konferensbidrag (refereegranskat)abstract
- Bandwidth reservation is a procedure that can be applied to give higher priority to certain connection types in cellular networks. Subscriber movement predictions can be used to determine the amount of bandwidth to be reserved in each cell. The prediction accuracy is significantly unproved if both the approximate subscriber locations in the cell and stored subscriber movement data are taken into account in the prediction procedure. The obtained accuracy improvement reduces the call blocking and/or handover dropping probabilities in the network. In this paper, the efficiency of including a cell zone partitioning feature in the bandwidth reservation procedure will be studied. Each cell is partitioned into smaller cell areas, denoted zones, and it is continuously tracked in which zone every single ongoing call is located. Different zone configurations and subscriber mobility parameters as well as the impacts of imperfect positioning will be considered in the performance analysis.
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