| 1. |
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| 2. |
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| 3. |
- Andersson, Bo, et al.
(author)
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A general model for jet fragmentation
- 1983
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In: European Physical Journal C. - 0170-9739. ; 20:4, s. 317-329
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Journal article (peer-reviewed)abstract
- We present a general condition on quark fragmentation which gives a hadron distribution satisfying Lorentz invariance and causality. The hadronization can be described as an iterative cascade process, symmetric with respect to iteration from the quark and the antiquark ends. The possible particle distributions are strongly restricted, with few free parameters related to the total multiplicity and corelations in rapidity. These parameters can be given an appealing interpretation in terms of the expected area and perimeter dependence of Wilson loop integrals.
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| 4. |
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| 5. |
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| 6. |
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| 7. |
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| 8. |
- Andersson, Bo, et al.
(author)
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Coherence Effects in Deep Inelastic Scattering
- 1989
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In: Zeitschrift für Physik C Particles and Fields. - 0170-9739. ; 43:4, s. 625-632
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Journal article (peer-reviewed)abstract
- We present a framework for deep inelastic scattering, with bound state properties in accordance with a QCD force field acting like a vortex line in a colour superconducting vacuum, which implies some simple coherence effects. Within this scheme one may describe the results of present energies very well, but one obtains an appreciable depletion of gluon radiation in the HERA energy regime.
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| 9. |
- Andersson, Bo, et al.
(author)
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Gluon Splitting in the Color Dipole Cascades
- 1990
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In: Nuclear Physics B. - 0550-3213. ; 339:2, s. 393-405
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Journal article (peer-reviewed)abstract
- We present a method to implement the gluon splitting process, g → QQ, into the dipole approximation to QCD cascades. It is known that due to the uncertainties in the interpolation between the pole regions, there are large uncertainties in the results. We show that there are further uncertainties due to the ordering in phase space of the gluon emission and gluon splitting processes. We present two options called the IO scheme (for independent dipoles) and another, the DO scheme (corresponding to an ordering in transverse momentum of the emissions) both of which lead to enhanced (hard) QQ-pair production, as compared to conventional cascades. We compare to present experimental data and give predictions for LEP energies.
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| 10. |
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| 11. |
- Andersson, Bo, et al.
(author)
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Implications of a large vector meson production on quark jet fragmentation and large p T reactions
- 1978
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In: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 18:4, s. 193-195
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Journal article (peer-reviewed)abstract
- A large vector meson production in quark jet fragmentation implies characteristic differences between the kaon and pion spectra. This prediction is verified in a recent SLAC-MIT experiment. Similar considerations are relevant for the c-quark fragmentation into D-mesons, as observed in ν scattering experiments.The difference in kaon and pion spectra provides a test of the hard quark-quark scattering description of large p T events. In particular the K+/π+ ratio (∼ 1/2 for single particle triggers) should be around 0.1-0.2 for jet triggers.
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| 12. |
- Andersson, Bo, et al.
(author)
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Investigations into the BFKL mechanism with a running QCD coupling
- 1998
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In: Physical Review D (Particles and Fields). - 0556-2821. ; 57:9, s. 5543-5554
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Journal article (peer-reviewed)abstract
- We present approximations of varying degree of sophistication to the integral equations for the (gluon) structure functions of a hadron ("the partonic flux factor") in a model valid in the leading log approximation with a running coupling constant. The results are all of the BFKL type, i.e., a power in the Bjorken variable x(B)(-lambda) with the parameter lambda determined from the size alpha(0) of the "effective" running coupling <(alpha)over bar>=3 alpha(s)/pi =alpha(0)/ln(k(perpendicular to)(2)) and varying depending upon the treatment of the transverse momentum pole, we also consider the implications for the transverse momentum (k(perpendicular to)) fluctuations along the emission chains and we obtain an exponential falloff in the relevant kappa=ln(k(perpendicular to)(2)) variable, i.e., an inverse power (k(perpendicular to)(2))(-(2+lambda)) with the same parameter lambda. This is different from the BFKL result for a fixed coupling, where the distributions are Gaussian in the kappa variable with a width as in a Brownian motion determined by "the length" of the emission chains, i.e., In(1/x(B)). The results are verified by a realistic Monte Carlo simulation and we provide a simple physics motivation for the change.
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| 13. |
- Andersson, Bo, et al.
(author)
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Is there screwiness at the end of the QCD cascades?
- 1998
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In: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479. ; :9
-
Journal article (peer-reviewed)abstract
- We discuss what happens at the end of the QCD cascades. We show that, with just a few reasonable assumptions, the emission of soft gluons is constrained to produce an ordered field in the form of a helix. We describe how to modify the Lund fragmentation scheme in order to fragment such a field. Our modified fragmentation scheme yields results which are consistent with current experimental measurements, but predicts at least one signature which should be observable.
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| 14. |
- Andersson, Bo, et al.
(author)
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ON HIGH-ENERGY LEPTOPRODUCTION
- 1981
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In: Zeitschrift für Physik C Particles and Fields. - 0170-9739. ; C9, s. 233-233
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Journal article (peer-reviewed)
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| 15. |
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| 16. |
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| 17. |
- Andersson, Bo, et al.
(author)
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Quark Jet Fragmentation
- 1979
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In: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 19:2, s. 184-190
-
Journal article (peer-reviewed)abstract
- A semiclassical model is presented for the way the energy of a fast quark is transformed into observable hadrons. It reproduces the features of 1 + 1 dimensional QED (the Schwinger model) concerning a flat rapidity distribution in the central region. In particular the model predicts that the probability to find a meson containing a leading quark is independent of the Feynman scaling variable. Also a quark jet interpretation of low PT jets in hadronic interactions is discussed shortly.
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| 18. |
- Andersson, Bo, et al.
(author)
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Small x phenomenology: summary and status
- 2002
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In: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 25:1, s. 77-101
-
Research review (peer-reviewed)abstract
- The aim of this paper is to summarize the general status of our understanding of small-x physics. It is based on presentations and discussions at an informal meeting OIL this topic held in Lund, Sweden, in March 2001. This document also marks the founding of an informal collaboration between experimentalists and theoreticians with a special interest in small-x physics. This paper is dedicated to the memory of Bo Andersson. who died unexpectedly from a heart attack on March 4th, 2002.
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| 19. |
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| 20. |
- Andersson, Bo, et al.
(author)
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Structure Functions and general final state properties in the linked dipole chain model
- 1996
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In: Zeitschrift für Physik C Particles and Fields. - : Springer Science and Business Media LLC. - 0170-9739 .- 1431-5858. ; 71:4, s. 613-624
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Journal article (peer-reviewed)abstract
- We have in an earlier paper, [1], presented a generalization, the Linked Dipole Chain Model LDC, of the model developed by Ciafaloni-Catani-Fiorani-Marchesini, [2], to decribe the structure functions and the states in Deep Inelastic Scattering events. In this paper we would like to present an investigation of a set of general features of the LDC Model, viz the behaviour of the structure functions (we will show how the result interpolates in a precise way in between the well-known DGLAP and BFKL approaches), the average bremsstrahlung emission in the states and finally a partitioning of the structure functions into three different channels: the ''ordinary'' parton-probe events, where all bremsstrahlung emissions are below the probe Q(2), the boson-gluon fusion events where the last splitting of the par ton chains contain transverse momentum above Q(2), and the resolved Rutherford scattering events between the probe and the hadron (where the largest transverse momentum occur somewhere along the emission lines away from the ends).
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| 21. |
- Andersson, Bo, et al.
(author)
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The Feynman-Wilson gas and the Lund model
- 1999
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In: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 7:2, s. 251-261
-
Journal article (peer-reviewed)abstract
- We derive a partition function for the Lund fragmentation model and compare it with that of a classical gas. For a fixed rapidity “volume” this partition function corresponds to a multiplicity distribution which is very close to a binomial distribution. We compare our results with the multiplicity distributions obtained from the JETSET Monte Carlo for several scenarios. Firstly, for the fragmentation vertices of the Lund string. Secondly, for the final state particles both with and without decays.
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| 22. |
- Andersson, Bo, et al.
(author)
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The flavouring of a gluon jet
- 1990
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In: Physics Letters B. - 0370-2693. ; 236:4, s. 461-465
-
Journal article (peer-reviewed)abstract
- We show that the hard qq̄ production is very sensitive to the details of the parton shower and that our treatment based on the dipole approximation gives significantly larger production than “conventional” parton showers. For our model we find qualitative agreement with experimental data for the Kπ ratio and D-meson production in high-pT jets.
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| 23. |
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| 24. |
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| 25. |
- Asif, Sana, et al.
(author)
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Heparinization of cell surfaces with short peptide-conjugated PEG-lipid regulates thromboinflammation in transplantation of human MSCs and hepatocytes
- 2016
-
In: Acta Biomaterialia. - : Elsevier BV. - 1742-7061 .- 1878-7568. ; 35, s. 194-205
-
Journal article (peer-reviewed)abstract
- Infusion of therapeutic cells into humans is associated with immune responses, including thromboinflammation, which result in a large loss of transplanted cells\ To address these problems, heparinization of the cell surfaces was achieved by a cell-surface modification technique using polyethylene glycol conjugated phospholipid (PEG-lipid) derivatives. A short heparin-binding peptide was conjugated to the PEG-lipid for immobilization of heparin conjugates on the surface of human mesenchymal stem cells (hMSCs) and human hepatocytes. Here three kinds of heparin-binding peptides were used for immobilizing heparin conjugates and examined for the antithrombogenic effects on the cell surface. The heparinized cells were incubated in human whole blood to evaluate their hemocompatibility by measuring blood parameters such as platelet count, coagulation markers, complement markers, and Factor Xa activity. We found that one of the heparin-binding peptides did not show cytotoxicity after the immobilization with heparin conjugates. The degree of binding of the heparin conjugates on the cell surface (analyzed by flow cytometer) depended on the ratio of the active peptide to control peptide. For both human MSCs and hepatocytes in whole-blood experiments, no platelet aggregation was seen in the heparin conjugate-immobilized cell group vs. the controls (non-coated cells or control peptide). Also, the levels of thrombin-antithrombin complex (TAT), C3a, and sC5b-9 were significantly lower than those of the controls, indicating a lower activation of coagulation and complement. Factor Xa analysis indicated that the heparin conjugate was still active on the cell surface at 24 h post-coating. It is possible to immobilize heparin conjugates onto hMSC and human hepatocyte surfaces and thereby protect the cell surfaces from damaging thromboinflammation. Statement of Signigficance We present a promising approach to enhance the biocompatibility of therapeutic cells. Here we used short peptide-conjugated PEG-lipid for cell surface modification and heparin conjugates for the coating of human hepatocytes and MSCs. We screened the short peptides to find higher affinity for heparinization of cell surface and performed hemocompatibility assay of heparinized human hepatocytes and human MSCs in human whole blood. Using heparin-binding peptide with higher affinity, not only coagulation activation but also complement activation was significantly suppressed. Thus, it was possible to protect human hepatocytes and human MSCs from the attack of thromboinflammatory activation, which can contribute to the improvement graft survival. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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| 26. |
- Bauer, Betty, et al.
(author)
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Right temporal lobe activation when listening to emotionally significant music
- 2004
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In: Applied Neuropsychology. - : Informa UK Limited. - 0908-4282 .- 1532-4826. ; 11:3, s. 161-166
-
Journal article (peer-reviewed)abstract
- The cerebral activation when normal elderly participants (6 women, 6 men, M age = 70 years) listened to self-selected emotionally significant music was investigated. Musical memories and preferences were discussed in an interview, and a piece of music with great emotional significance to the participant was selected and later played during measurement of the regional cerebral blood flow (rCBF). Measurements were made during silence, individually selected emotional music, and standard neutral music. The right temporal lobe showed a significant (p < .01) increase in rCBF when the emotional music was compared to silence. A temporal lobe asymmetry (right > left) during emotional music was also significant (p < .01). A decrease in the left prefrontal areas reached significance (p < .05) when standard music was compared to silence. For the emotional music, the right prefrontal area showed a decrease (p < .05). Emotional music thus activates right temporal and deactivates prefrontal regions in the right hemisphere.
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| 27. |
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| 28. |
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| 29. |
- Choong, P F, et al.
(author)
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Prognostic value of Ki-67 expression in 182 soft tissue sarcomas. Proliferation--a marker of metastasis?
- 1994
-
In: APMIS : acta pathologica, microbiologica, et immunologica Scandinavica. - 1600-0463. ; 102:12, s. 915-924
-
Journal article (peer-reviewed)abstract
- Soft tissue sarcomas (STS) are characterized by deregulated proliferation. Ki-67 is a cell cycle antigen which may be elevated in proliferative states. We analysed Ki-67 expression in fixed and embedded tissues from STS in order to examine associations between proliferation, primary tumour characteristics, and metastasis. One hundred and eighty-two adult patients with trunk wall or extremity STS were treated at our institution between 1980 and 1992 (35 developed local recurrence and 56 developed metastases). Median follow-up time for survivors was 6 years (1-13). We used a semiquantitative score to the assess percentage of Ki-67-positive cells: < or = 10% (n = 86), > 10-25% (n = 57), > 25-50% (n = 30), > 50-75% (n = 7), > 75-100% (n = 2). Increasing Ki-67 expression correlated positively with tumour size, malignancy grade, necrosis, vascular invasion, S-phase fraction, and metastasis. A Ki-67 index Ki-D < or = 10% (n = 86) and > 10% (n = 96) defined two groups who had 84% and 56% 3-year metastasis-free survival (p = 0.0001), respectively. Tumours with Ki-D > 10 were typically large, high grade, necrotic, DNA aneuploid, and had intravascular invasion and a higher S-phase fraction. Ki-67 expression may be helpful in predicting survival of patients with soft tissue sarcomas.
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| 30. |
- Dreinhofer, KE, et al.
(author)
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DNA ploidy in soft tissue sarcoma: Comparison of flow and image cytometry with clinical follow-up in 93 patients : comparison of flow and image cytometry with clinical follow-up in 93 patients
- 2002
-
In: Cytometry. - : Wiley. - 0196-4763. ; 50:1, s. 19-24
-
Journal article (peer-reviewed)abstract
- In soft tissue sarcoma, the prognostic importance of DNA ploidy status is limited. One possible explanation may be technical; small nondiploid stemlines will he diluted in relation to the presence of normal diploid cells and may not be detected by flow cytometry (FCM). We assessed DNA ploidy status in 93 tumors with both FCM and image cytometry (ICM). ICM may permit the exclusion of nonrelevant cells. The ability of the two methods to detect nondiploid stemlines was compared, as were the prognostic consequences. The patients (54 males) had a median age of 69 years. Surgical procedures were performed on all patients. None of the patients had received preoperative radiotherapy or chemotherapy. FCM and ICM were performed with standard methods. The prognostic value was assessed with univariate and multivariate analysis. In 82 of the 93 tumors, a concordant ploidy status by FCM and ICM was found. In 5 FCM type 1-2 tumors (diploid), the identification of nondiploid stemlines by ICM did not influence the metastatic rates. Increasing tumor size, histotype other than liposarcoma, increasing malignancy grade, tumor necrosis, and ICM nondiploidy were univariate prognostic factors for metastasis. In a multivariate analysis, only tumor size larger than 9 cm was a prognostic factor. In about 10% of the tumors, a discrepancy between FCM and ICM ploidy status was found, but we could not find a consistent prognostic consequence of this. Neither FCM nor ICM ploidy status was an independent prognostic factor. (C) 2002 Wiley-Liss, Inc.
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| 31. |
- Friedland, René, et al.
(author)
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Effects of Nutrient Management Scenarios on Marine Eutrophication Indicators : A Pan-European, Multi-Model Assessment in Support of the Marine Strategy Framework Directive
- 2021
-
In: Frontiers in Marine Science. - : Frontiers Media SA. - 2296-7745. ; 8
-
Journal article (peer-reviewed)abstract
- A novel pan-European marine model ensemble was established, covering nearly all seas under the regulation of the Marine Strategy Framework Directive (MSFD), with the aim of providing a consistent assessment of the potential impacts of riverine nutrient reduction scenarios on marine eutrophication indicators. For each sea region, up to five coupled biogeochemical models from institutes all over Europe were brought together for the first time. All model systems followed a harmonised scenario approach and ran two simulations, which varied only in the riverine nutrient inputs. The load reductions were evaluated with the catchment model GREEN and represented the impacts due to improved management of agriculture and wastewater treatment in all European river systems. The model ensemble, comprising 15 members, was used to assess changes to the core eutrophication indicators as defined within MSFD Descriptor 5. In nearly all marine regions, riverine load reductions led to reduced nutrient concentrations in the marine environment. However, regionally the nutrient input reductions led to an increase in the non-limiting nutrient in the water, especially in the case of phosphate concentrations in the Black Sea. Further core eutrophication indicators, such as chlorophyll-a, bottom oxygen and the Trophic Index TRIX, improved nearly everywhere, but the changes were less pronounced than for the inorganic nutrients. The model ensemble displayed strong consistency and robustness, as most if not all models indicated improvements in the same areas. There were substantial differences between the individual seas in the speed of response to the reduced nutrient loads. In the North Sea ensemble, a stable plateau was reached after only three years, while the simulation period of eight years was too short to obtain steady model results in the Baltic Sea. The ensemble exercise confirmed the importance of improved management of agriculture and wastewater treatments in the river catchments to reduce marine eutrophication. Several shortcomings were identified, the outcome of different approaches to compute the mean change was estimated and potential improvements are discussed to enhance policy support. Applying a model ensemble enabled us to obtain highly robust and consistent model results, substantially decreasing uncertainties in the scenario outcome. ABSTRACT A novel pan-European marine model ensemble was established, covering nearly all seas under the regulation of the Marine Strategy Framework Directive (MSFD), with the aim of providing a consistent assessment of the potential impacts of riverine nutrient reduction scenarios on marine eutrophication indicators. For each sea region, up to five coupled biogeochemical models from institutes all over Europe were brought together for the first time. All model systems followed a harmonised scenario approach and ran two simulations, which varied only in the riverine nutrient inputs. The load reductions were evaluated with the catchment model GREEN and represented the impacts due to improved management of agriculture and wastewater treatment in all European river
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| 32. |
- Guo, Xinxin, 1972, et al.
(author)
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Midlife respiratory function related to white matter lesions and lacunar infarcts in late life: the Prospective Population Study of Women in Gothenburg, Sweden.
- 2006
-
In: Stroke; a journal of cerebral circulation. - 1524-4628. ; 37:7, s. 1658-62
-
Journal article (peer-reviewed)abstract
- BACKGROUND AND PURPOSE: Increased evidence suggests that poor respiratory function increases risk of ischemic damage to the brain. Longitudinal studies on respiratory function and cerebral small-vessel disease are lacking. We examined midlife and late-life respiratory function in relation to small-vessel disease on computed tomography (CT) in women followed for 26 years. METHODS: White matter lesions (WMLs) and lacunar infarcts were rated on brain CT scans in 2000 in 379 women 70 to 92 years of age from a longitudinal population study in Göteborg, Sweden. Respiratory function was measured by peak expiratory flow (PEF) in 1974 and 2000 and by forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) in 1980 and 2000. RESULTS: Lower FVC and FEV1 in 1980 and 2000 were associated with presence and severity of WMLs and lacunar infarcts in 2000. Per 1-SD decrease of FVC in 1980, odds ratios (95% CIs) were 1.49 (1.11 to 2.02) for presence of WMLs and 1.95 (1.34 to 2.84) for lacunar infarcts after adjustment for potential confounders. Per 1-SD decrease of FEV1 in 1980, adjusted odds ratios were 1.46 (1.06 to 2.00) for presence of WMLs and 1.42 (1.02 to 1.97) for lacunar infarcts. PEF in 1974 and 2000 was not associated with WMLs or lacunar infarcts. CONCLUSIONS: WMLs and lacunar infarcts in elderly women were related to lower midlife respiratory function. Although our data may not establish causation between lower respiratory function and small-vessel disease, they imply the importance of good respiratory function in midlife.
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| 33. |
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| 34. |
- Gustafson, Elisabet, et al.
(author)
-
Control of IBMIR Induced by Fresh and Cryopreserved Hepatocytes by Low Molecular Weight Dextran Sulfate Versus Heparin
- 2017
-
In: Cell Transplantation. - : Sage Publications. - 0963-6897 .- 1555-3892. ; 26:1, s. 71-81
-
Journal article (peer-reviewed)abstract
- Rapid destruction of hepatocytes after hepatocyte transplantation has hampered the application of this procedure clinically. The instant blood-mediated inflammatory reaction (IBMIR) is a plausible underlying cause for this cell loss. The present study was designed to evaluate the capacity of low molecular weight dextran sulfate (LMW-DS) to control these initial reactions from the innate immune system. Fresh and cryopreserved hepatocytes were tested in an in vitro whole-blood model using ABO-compatible blood. The ability to elicit IBMIR and the capacity of LMW-DS (100 mu g/ml) to attenuate the degree of activation of the cascade systems were monitored. The effect was also compared to conventional anticoagulant therapy using unfractionated heparin (1 IU/ml). Both fresh and freeze thawed hepatocytes elicited IBMIR to the same extent. LMW-DS reduced the platelet loss and maintained the cell counts at the same degree as unfractionated heparin, but controlled the coagulation and complement systems significantly more efficiently than heparin. LMW-DS also attenuated the IBMIR elicited by freeze thawed cells. Therefore, LMW-DS inhibits the cascade systems and maintains the cell counts in blood triggered by both fresh and cryopreserved hepatocytes in direct contact with ABO-matched blood. LMW-DS at a previously used and clinically applicable concentration (100 mu g/ml) inhibits IBMIR in vitro and is therefore a potential IBMIR inhibitor in hepatocyte transplantation.
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| 35. |
- Gustafson, Elisabet K., et al.
(author)
-
Exposure of von Willebrand Factor on Isolated Hepatocytes Promotes Tethering of Platelets to the Cell Surface
- 2019
-
In: Transplantation. - : Wolters Kluwer. - 0041-1337 .- 1534-6080. ; 103:8, s. 1630-1638
-
Journal article (peer-reviewed)abstract
- Background. Hepatocyte transplantation (Hctx) is a potentially attractive method for the treatment of acute liver failure and liver-based metabolic disorders. Unfortunately, the procedure is hampered by the instant blood-mediated inflammatory reaction (IBMIR), a thromboinflammatory response elicited by the vascular innate immune system, causing activation of the coagulation and complement systems and clearance of transplanted cells. Observations have also revealed platelets adhered to the surface of the hepatocytes (Hc). To establish Hctx as a clinical treatment, all factors that trigger IBMIR need to be identified and controlled. This work explores the expression of von Willebrand factor (VWF) on isolated Hc resulting in tethering of platelets. Methods. VWF on Hc was studied by flow cytometry, confocal microscopy, immunoblot, and real-time polymerase chain reaction. Interaction between Hc and platelets was studied in a Chandler loop model. Adhesion of platelets to the hepatocyte surface was demonstrated by flow cytometry and confocal microscopy. Results. Isolated Hc constitutively express VWF on their cell surface and mRNA for VWF was found in the cells. Hc and platelets, independently of coagulation formed complexes, were shown by antibody blocking studies to be dependent on hepatocyte-associated VWF and platelet-bound glycoprotein Ib alpha. Conclusions. VWF on isolated Hc causes, in contact with blood, adhesion of platelets, which thereby forms an ideal surface for coagulation. This phenomenon needs to be considered in hepatocyte-based reconstitution therapy and possibly even in other settings of cell transplantation.
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| 36. |
- Gustafson, Elisabet K., et al.
(author)
-
The Instant Blood-Mediated Inflammatory Reaction Characterized in Hepatocyte Transplantation
- 2011
-
In: Transplantation. - 0041-1337 .- 1534-6080. ; 91:6, s. 632-638
-
Journal article (peer-reviewed)abstract
- Background. Hepatocyte transplantation (HcTx) has proven to be a safe procedure, although the functional results have been unsatisfactory, probably due to insufficient engraftment or a loss of transplanted mass or function. In this study, we investigate whether hepatocytes in contact with blood induce an inflammatory reaction leading to, similar to what happens in clinical islet transplantation, an instant blood-mediated inflammatory reaction (IBMIR) resulting in an early loss of transplanted cells. Methods. By using an experimental model that mimics the portal vein blood flow, we could study different parameters reflecting the effects on the innate immunity elicited by hepatocytes in contact with ABO-matched human blood. Results. We report that all aspects of the IBMIR such as platelet and granulocyte consumption, coagulation, and complement activation were demonstrated. Addition of various specific inhibitors of coagulation allowed us to clearly delineate the various stages of the hepatocyte-triggered IBMIR and show that the reaction was triggered by tissue factor. Analysis of a case of clinical HcTx showed that hepatocyte-induced IBMIR also occurs in vivo. Both the inflammatory and the coagulation aspects were controlled by low-molecular-weight dextran sulfate. Conclusion. Isolated hepatocytes in contact with blood induce the IBMIR in vitro, and there are indications that these events are also relevant in vivo. According to these findings, HcTx would benefit from controlling a wider range of signals from the innate immune system.
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| 37. |
- Gustafson, Elisabet
(author)
-
Thromboinflammation : in a Model of Hepatocyte Transplantation
- 2016
-
Doctoral thesis (other academic/artistic)abstract
- Hepatocyte transplantation is an attractive method for the treatment of metabolic liver disease and acute liver failure. The clinical application of this method has been hampered by a large initial loss of transplanted cells.This thesis has identified and characterized an instant blood-mediated inflammatory reaction (IBMIR), which is a thromboinflammatory response from the innate immunity that may partly explain the observed loss of cells. In vitro perifusion experiments were performed and established that hepatocytes in contact with blood activate the complement and coagulation systems and induce clot formation in conjunction with the recruitment of neutrophils. Within an hour, the hepatocytes were surrounded by platelets and entrapped in a clot infiltrated by neutrophils. Furthermore, hepatocytes expressed tissue factor (TF), and the reactions were shown to be initiated through the TF pathway. Monitoring of hepatocyte transplantation in vivo revealed activation of the same parameters as were noted in vitro.For the first time, von Willebrand factor (vWF) was identified on the hepatocyte surface, being demonstrated by flow cytometry and confocal microscopy. mRNA for vWF was also confirmed in hepatocytes. Complex formation between platelets and hepatocytes was also identified. Addition of antibodies targeting the binding site for vWF on the platelets reduced the complex formation.Two different strategies, systemic and local intervention, were applied to diminish the thromboinflammation elicited from the hepatocytes in contact with ABO-matched blood. Systemic inhibition with LMW-DS, in a clinically applicable dose, was found to be superior in controlling the IBMIR in vitro when compared to heparin. Cryopreserved hepatocytes elicited the IBMIR to the same extent as did fresh hepatocytes, and the IBMIR was equally well controlled with LMW-DS in both cryopreserved and fresh cells.Hepatocytes were coated with two layers of immobilized heparin in an attempt to protect the cells from the IBMIR. In vitro perifusion experiments showed heparinized hepatocytes triggered a significantly lower degree of IBMIR.
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| 38. |
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| 39. |
- Gustafson, Pelle, et al.
(author)
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Flow cytometric S-phase fraction in soft-tissue sarcoma: prognostic importance analysed in 160 patients
- 1997
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In: British Journal of Cancer. - 1532-1827. ; 75:1, s. 94-100
-
Journal article (peer-reviewed)abstract
- We could determine the S-phase fraction (SPF) by flow cytometric DNA analysis of paraffin archival material in 160 of 260 patients with soft-tissue sarcoma of extremity and trunk wall. The prognostic value of SPF was compared with other clinicopathological factors. The median follow-up time was 16 (6-31) years. In a univariate analysis, deep tumour location, increasing tumour size and histological malignancy grade, microscopic tumour necrosis, vascular invasion, DNA non-diploidy and high SPF (>3.0%) were associated with poor metastasis-free survival. In a multivariate analysis, microscopic tumour necrosis and high SPF were independently prognostic for metastasis. Used in combination with tumour size, microscopic tumour necrosis and vascular invasion, SPF could identify a group of patients with a 5-year metastasis-free survival rate of 0.97. This group constituted one-quarter of all patients. Patients with low SPF who did recur had a prolonged clinical course both as regards metastases and local recurrence. We conclude that SPF is a valuable adjunct in prognostication in soft-tissue sarcoma.
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| 40. |
- Gustafson, Pelle, et al.
(author)
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Liposarcoma: a population-based epidemiologic and prognostic study of features of 43 patients, including tumor DNA content
- 1993
-
In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 55:4, s. 541-546
-
Journal article (peer-reviewed)abstract
- Different conceptions exist regarding the epidemiology and prognosis of liposarcoma, and several classification systems are in use. We analyzed a population-based, 25-year series of 43 patients with liposarcoma of the extremity or trunk wall. Follow-up was complete. The annual incidence was 0.12/10(5). The thigh was the most common location. One of 6 tumors was subcutaneous. Deep-seated tumors were larger than s.c. tumors. Among the 42 surgically treated patients, grade II (4-grade scale) was the most common malignancy grade. Four tumors were well-differentiated, 24 were predominantly myxoid, 4 predominantly round-cell, and 10 were predominantly of pleomorphic type. The 5-year metastasis-free survival rate was 69%. By univariate analysis increasing malignancy grade, tumor necrosis, vascular invasion, mitotic count, subtype other than well-differentiated, and high cellularity were prognostic for metastatic disease. However, in the multivariate analysis only tumor necrosis was an independent risk factor. Tumor necrosis should be considered when prognosis of liposarcoma of the extremity and trunk wall is evaluated.
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| 41. |
- Gustafson, Pelle, et al.
(author)
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Prognostic implications of various models for calculation of S-phase fraction in 259 patients with soft tissue sarcoma
- 1999
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In: British Journal of Cancer. - : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 79, s. 1205-1209
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Journal article (peer-reviewed)abstract
- The S-phase fraction (SPF) in flow cytometric DNA histograms in soft tissue sarcoma (STS) can be calculated in various ways. The traditional planimetric method of Baisch has been shown to be prognostic, but is hampered by a failure rate of around 40%. We therefore tested other models to see if this rate could be decreased with retained prognostic value. In 259 STS of the locomotor system the SPF was calculated according to Baisch and with commercial parametric MultiCycle software using different corrections for background. Using the Baisch model, 159 histograms could be evaluated for SPF. The 5-year metastasis-free survival rate (MFSR) was 0.94 for the low-risk group (defined with SPF), and 0.53 for the high-risk group. In the low-risk group, four of the seven patients who developed metastasis did so after 5 years Using the MultiCycle software, SPF could be calculated in 253 tumours. Depending on type of background correction used, the 5-year MFSR varied between 0.67 and 0.82 for the low-risk group, and between 0.47 and 0.53 for the high-risk group. The late metastasis pattern in the low-risk group was never seen using the MultiCycle software. We conclude that in paraffin archival material, calculation of SPF according to Baisch is preferable in clinical use due to better separation between low-risk and high-risk groups, and also the possibility to identify patients who metastasize late.
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| 42. |
- Gustafson, Pelle, et al.
(author)
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Soft tissue leiomyosarcoma. A population-based epidemiologic and prognostic study of 48 patients, including cellular DNA content
- 1992
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In: Cancer. - 1097-0142. ; 70:1, s. 114-119
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Journal article (peer-reviewed)abstract
- BACKGROUND. Leiomyosarcoma of soft tissue is a rare tumor. There are different opinions regarding epidemiology and prognosis. METHODS. Epidemiology and prognosis were analyzed in a consecutive, population-based series of 48 patients with subcutaneous and deep-seated leiomyosarcoma in the extremities and trunk wall with a complete follow-up of a minimum of 3 years. Cutaneous tumors were not included. RESULTS. The annual incidence was 0.13/10(5). The ratio of men to women was 1.2, and the median age was 65 years. The thigh was the most common location. Almost half of the tumors were subcutaneous. The median tumor size was 6 cm (range, 1-25 cm). All patients were treated with surgery, and in 19 cases it was combined with adjuvant radiation therapy or chemotherapy. The cumulative 5-year survival rate was 64%. Multivariate analysis indicated that age of 60 years or greater (relative risk [RR] = 8) and intratumoral vascular invasion (RR = 4) were independent risk factors for death resulting from tumor. DNA aneuploidy (RR = 4) and tumor necrosis (RR = 3) were associated with poor prognosis, but did not reach statistic significance. CONCLUSIONS. Advanced age, vascular invasion, and DNA aneuploidy could be used to identify prognostic subgroups.
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| 43. |
- Gustafson, Pernilla, 1978, et al.
(author)
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The impact of domestic wood burning on personal, indoor and outdoor levels of 1,3-butadiene, benzene, formaldehyde and acetaldehyde
- 2007
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In: J Environ Monit. ; 9:1, s. 23-32
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Journal article (peer-reviewed)abstract
- The aim of this study was to quantify personal exposure and indoor levels of the suspected or known carcinogenic compounds 1,3-butadiene, benzene, formaldehyde and acetaldehyde in a small Swedish town where wood burning for space heating is common. Subjects (wood burners, n = 14), living in homes with daily use of wood-burning appliances were compared with referents (n = 10) living in the same residential area. Personal exposure and stationary measurements indoors and at an ambient site were performed with diffusive samplers for 24 h. In addition, 7 day measurements of 1,3-butadiene and benzene were performed inside and outside the homes. Wood burners had significantly higher median personal exposure to 1,3-butadiene (0.18 microg m(-3)) compared with referents (0.12 microg m(-3)), which was also reflected in the indoor levels. Significantly higher indoor levels of benzene were found in the wood-burning homes (3.0 microg m(-3)) compared with the reference homes (1.5 microg m(-3)). With regard to aldehydes, median levels obtained from personal and indoor measurements were similar although the four most extreme acetaldehyde levels were all found in wood burners. High correlations were found between personal and indoor levels for all substances (r(s) > 0.8). In a linear regression model, type of wood-burning appliance, burning time and number of wood replenishments were significant factors for indoor levels of 1,3-butadiene. Domestic wood burning seems to increase personal exposure to 1,3-butadiene as well as indoor levels of 1,3-butadiene and benzene and possibly also acetaldehyde. The cancer risk from these compounds at exposure to wood smoke is, however, estimated to be low in developed countries.
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| 44. |
- Gustafson, Rolf, et al.
(author)
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Prevalence of Borrelia burgdorferi sensu lato infection in Ixodes ricinus in Sweden
- 1995
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In: Scandinavian Journal of Infectious Diseases. - : Informa UK Limited. - 0036-5548 .- 1651-1980. ; 27:6, s. 597-601
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Journal article (peer-reviewed)abstract
- Between 1988-1991, a total of 3,141 Ixodes ricinus ticks, 2,740 adults and 401 nymphs, was collected from different localities in 23 of the 25 provinces of Sweden. The ticks were identified, dissected and examined for the presence of Borrelia spirochetes. Indirect immunofluorescence was performed, using an antiserum obtained from rabbits, immunized with sonicated, whole Borrelia burgdorferi spirochetes isolated from Swedish Ixodes ricinus ticks. Borrelia-positive I. ricinus were found in all 23 provinces. The prevalence of infection in adults ranged from 3% in Jämtland to 23% in Södermanland. In nymphs, the infection prevalence ranged from 0% in 9 provinces to 15% in Södermanland. A significantly greater proportion of the adult ticks were found to be positive for Borrelia in the southern and central parts of Sweden as compared to the northern part (Norrland). No significant difference in prevalence could be demonstrated between the western and eastern parts of Sweden. On average, 10% of the nymphs and 15% of the adult I. ricinus were positive for Borrelia. Of 41 non-I. ricinus ticks, none was positive for Borrelia. This study shows that Borrelia burgdorferi sensu lato is present throughout the distributional area of I. ricinus in Sweden. This should lead to increased awareness of signs and symptoms compatible with Lyme borreliosis in persons living in or visiting areas where I. ricinus is present.
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| 45. |
- Gustafson, Stefan, et al.
(author)
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ICAM-1 is a cell-surface receptor for hyaluronan.
- 1995
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In: 6th Interscience World Conference on Inflammation, Antirheumatics, Analgesics, Immunomodulators, Geneva, Switzerland, 28-30 March, Abstract. ; 160, s. 28-
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Review (other academic/artistic)
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| 46. |
- Hörnsten, Carl, et al.
(author)
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High blood pressure as a risk factor for incident stroke among very old people : a population-based cohort study
- 2016
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In: Journal of Hypertension. - 0263-6352 .- 1473-5598. ; 34:10, s. 2059-2065
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Journal article (peer-reviewed)abstract
- INTRODUCTION: High blood pressure (BP) increases the risk of stroke, but there is limited evidence from studies including very old people. The aim was to investigate risk factors for incident stroke among very old people.METHODS: A prospective population-based cohort study was performed among participants aged at least 85 years in northern Sweden. The 955 participants were tested at their homes. BP was measured manually after 5-min supine rest. Incident stroke data were collected from medical charts guided by hospital registry, death records, and 5-year reassessments. Cox proportional hazards models were used.RESULTS: The stroke incidence was 33.8/1000 person-years (94 stroke events) during a mean follow-up period of 2.9 years. In a comprehensive multivariate model, atrial fibrillation [hazard ratio 1.85, 95% confidence interval (CI) 1.07-3.19] and higher SBP (hazard ratio 1.19, 95% CI 1.08-1.30 per 10-mmHg increase) were associated with incident stroke overall. However, higher SBP was not associated with incident stroke in participants with SBP less than 140 mmHg (hazard ratio 0.90, 95% CI 0.53-1.53 per 10-mmHg increase). In additional multivariate models, DBP at least 90 mmHg (hazard ratio 2.45, 95% CI 1.47-4.08) and SBP at least 160 mmHg (vs. <140 mmHg; hazard ratio 2.80, 95% CI 1.53-5.14) were associated with incident stroke. The association between BP and incident stroke was not affected by interactions related to sex, dependence in activities of daily living, or cognitive impairment.CONCLUSION: High SBP (≥160 mmHg) and DBP (≥90 mmHg) and atrial fibrillation appeared to be risk factors for incident stroke among very old people.
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| 47. |
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| 48. |
- Hörnsten, Carl, 1985-
(author)
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Stroke and depression in very old age
- 2016
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Doctoral thesis (other academic/artistic)abstract
- Background The prevalence and incidence of stroke are known to increase with age, which, combined with demographic change, means that very old patients with stroke are a growing patient group. Risk factors for incident stroke among very old people have not been widely investigated. The impact of depression on mortality in very old people who have had a stroke also remains unclear. The aim of this thesis was to investigate the risk factors for incident stroke, the epidemiology of stroke and depression, and the consequences of having had a stroke regarding the risk of depression and mortality among very old people.Methods A randomly selected half of 85-, all 90-, and all ≥95-year-olds in certain municipalities in Västerbotten County, Sweden, and Pohjanmaa County, Finland were targeted in a population-based cohort study from 2000-2012. The 65-, 70-, 75-, and 80-year-olds in all the rural and random samples from the urban municipalities in the same counties were furthermore targeted in a survey in 2010.In the cohort study patients were assessed in their homes, by means of the 15-item Geriatric Depression Scale (GDS-15) and other assessment scales, as well as blood pressure measurements, several physical tests, and a review of medical diagnoses appearing in the medical charts. Incident stroke data were collected from medical charts guided by hospital registry records, cause of death records, and reassessments after 5 years. Depression was defined as a GDS-15 score ≥5. A clinical definition of all depressive disorders, based on assessment scale scores and review of medical charts was also used. A specialist in geriatric medicine evaluated the diagnoses. The survey included yes/no questions about stroke and depression status, and the 4-item Geriatric Depression Scale. Associations with mortality and incident stroke were tested using Cox proportional-hazard models. Results In the ≥85-year-olds examined in 2005-2007 (n=601), the stroke prevalence was 21.5%, the prevalence of all depressive disorders was 37.8% and stroke was independently associated with depressive disorders (odds ratio 1.644, p=0.038). The prevalence of depression according to GDS-15 scores was 43.2% in people with stroke compared with 25.0% in people without stroke (p=0.001). However, in ≥85-year-olds examined in Sweden from 2000-2012 (n=955), from all past data collections in the study, depression was not independently associated with incident stroke. In ≥65-year-olds who responded to a survey in 2010 (n=6098), the stroke prevalence rose with age from 4.7% among the 65- to 11.6% among the 80-year-olds (p<0.001). The prevalence of depression rose from 11.0% among the 65- to 18.1% among the 80-year-olds (p<0.001). In the group with stroke, depression was independently associated with dependence in personal activities of daily living and having a life crisis the preceding year, while in the non-stroke group, depression was independently associated with several additional demographic, social and health factors.In ≥85-year-olds examined in 2005-2007 with valid GDS-15 tests (n=452), having had a stroke was associated with increased 5-year mortality [hazard ratio (HR) 1.53, 95% confidence interval (CI) 1.15-2.03]. Having had a stroke and depression was associated with increased 5-year mortality compared with having only stroke (HR 1.90, 95% CI 1.15-3.13), having only depression (HR 1.59, 95% CI 1.03-2.45), and compared with having neither stroke nor depression (HR 2.50, 95% CI 1.69-3.69). Having only stroke without a depression did not increase mortality compared with having neither stroke nor depression.In ≥85-year-olds examined in Sweden from 2000-2012 (n=955), from all past data collections in the study, the stroke incidence was 33.8/1000 person-years during a mean follow-up period of about three years. In a comprehensive multivariate model, atrial fibrillation (HR 1.85, 95% CI 1.07–3.19) and higher systolic blood pressure (SBP; HR 1.19, 95% CI 1.08–1.30 per 10-mmHg increase) were associated with incident stroke overall. In additional multivariate models, diastolic blood pressure (DBP) ≥90 mmHg (HR 2.45, 95% CI 1.47–4.08) and SBP ≥160 mmHg (v. <140 mmHg; HR 2.80, 95% CI 1.53–5.14) were associated with incident stroke.Conclusion The prevalence of both stroke and depression increased with age, and rates were especially high among very old people. Having had a stroke was independently associated with a higher prevalence of depression among very old people, however, depression was not independently associated with a higher incidence of stroke. Having had a stroke was associated with increased all-cause mortality among very old people, but only among those who were also depressed. High SBP (≥160 mmHg), DBP (≥90 mmHg) and atrial fibrillation were the only consistent independent risk factors for incident stroke among very old people.
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