| 1. |
- Inkinen, Satu, et al.
(författare)
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Collagen and chondrocyte concentrations control ultrasound scattering in agarose scaffolds
- 2014
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Ingår i: Ultrasound in Medicine and Biology. - : Elsevier. - 0301-5629 .- 1879-291X. ; 40:9, s. 2162-2171
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Tidskriftsartikel (refereegranskat)abstract
- Ultrasound imaging has been proposed for diagnostics of osteoarthritis and cartilage injuries in vivo. However, the specific contribution of chondrocytes and collagen to ultrasound scattering in articular cartilage has not been systematically studied. We investigated the role of these tissue structures by measuring ultrasound scattering in agarose scaffolds with varying collagen and chondrocyte concentrations. Ultrasound catheters with center frequencies of 9 MHz (7.1–11.0 MHz, −6 dB) and 40 MHz (30.1–45.3 MHz, −6 dB) were applied using an intravascular ultrasound device. Ultrasound backscattering quantified in a region of interest starting right below sample surface differed significantly (p < 0.05) with the concentrations of collagen and chondrocytes. An ultrasound frequency of 40 MHz, as compared with 9 MHz, was more sensitive to variations in collagen and chondrocyte concentrations. The present findings may improve diagnostic interpretation of arthroscopic ultrasound imaging and provide information necessary for development of models describing ultrasound propagation within cartilage.
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| 2. |
- Jensen, Jan S., et al.
(författare)
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Safety in simple versus complex stenting of coronary artery bifurcation lesions : The nordic bifurcation study 14-month follow-up results
- 2008
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Ingår i: EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology. - 1774-024X. ; 4:2, s. 229-233
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: The risk of stent thrombosis has been reported to increase with percutaneous coronary intervention (PCI) complexity. The present study reports the pre-specified secondary endpoint of a 14-month stent thrombosis and major adverse cardiac events in patients stented with a simple versus a complex bifurcation technique using sirolimus eluting stents (SES). METHODS AND RESULTS: A total of 413 patients with a coronary bifurcation lesion were randomised to a simple treatment strategy; stenting of main vessel and optional stenting of side branch (MV group), or to a complex stenting strategy; stenting of both main vessel and side branch (MV+SB group). Mortality data were available in all patients and 14-month clinical follow-up data in 395 (96%) of the patients. After 14 months, the rates of definite, probable and possible stent thrombosis (ARC criteria) were 1.0% vs. 0.5%, 1.0% vs. 0% and 0.5% vs. 0% (ns) in the MV and in the MV+SB groups, respectively. Rates of MACE were 9.5% in the MV group and 8.2% in the MV+SB group (ns). Total death was seen in 2.4% vs. 1.0% and non-PCI related myocardial infarction in 2.0% vs. 1.0% in the MV and the MV+SB groups, respectively. CONCLUSIONS: After 14 months, two months after recommended cessation of dual antiplatelet therapy, the rates of stent thrombosis and major adverse cardiac events were low and independent of treatment complexity in patients treated with SES for coronary artery bifurcation lesions.
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| 3. |
- Maeng, Michael, et al.
(författare)
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Long-Term Results After Simple Versus Complex Stenting of Coronary Artery Bifurcation Lesions : Nordic Bifurcation Study 5-Year Follow-Up Results
- 2013
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Ingår i: Journal of the American College of Cardiology. - : Elsevier BV. - 0735-1097 .- 1558-3597. ; 62:1, s. 30-34
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Tidskriftsartikel (refereegranskat)abstract
- Objectives This study sought to report the 5-year follow-up results of the Nordic Bifurcation Study. Background Randomized clinical trials with short-term follow-up have indicated that coronary bifurcation lesions may be optimally treated using the optional side branch stenting strategy. Methods A total of 413 patients with a coronary bifurcation lesion were randomly assigned to a simple stenting strategy of main vessel (MV) and optional stenting of side branch (SB) or to a complex stenting strategy, namely, stenting of both MV and SB. Results Five-year clinical follow-up data were available for 404 (98%) patients. The combined safety and efficacy endpoint of cardiac death, non-procedure-related myocardial infarction, and target vessel revascularization were seen in 15.8% in the optional SB stenting group as compared to 21.8% in the MV and SB stenting group (p = 0.15). All-cause death was seen in 5.9% versus 10.4% (p = 0.16) and non-procedure-related myocardial infarction in 4% versus 7.9% (p = 0.09) in the optional SB stenting group versus the MV and SB stenting group, respectively. The rates of target vessel revascularization were 13.4% versus 18.3% (p = 0.14) and the rates of definite stent thrombosis were 3% versus 1.5% (p = 0.31) in the optional SB stenting group versus the MV and SB stenting group, respectively. Conclusions At 5-year follow-up in the Nordic Bifurcation Study, the clinical outcomes after simple optional side branch stenting remained at least equal to the more complex strategy of planned stenting of both the main vessel and the side branch.
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| 4. |
- Puhakka, Mikko, et al.
(författare)
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Do an insider's wealth and income matter in the decision to engage in insider trading?
- 2018
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Ingår i: Journal of Financial Economics. - : Elsevier. - 0304-405X. ; 130:1, s. 135-165
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Tidskriftsartikel (refereegranskat)abstract
- We explore why insiders engage in informed trading, given the surprisingly small average insider returns reported in the literature and the potential costs involved. We begin by proposing a model of an insider's decision to engage in insider trading. We then empirically test the model's predictions using archival data of corporate insiders in Sweden. Consistent with the model, we find that less wealthy insiders are more likely to time their insider selling, and to sell in greater magnitudes, prior to abnormal price declines than wealthy insiders. We also find that less wealthy insiders with lower risk aversion as measured by their criminal behavior are particularly prone to timing their selling to avoid price declines.
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| 5. |
- Puhakka, Pia, et al.
(författare)
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Dependence of light attenuation and backscattering on collagen concentration and chondrocyte density in agarose scaffolds
- 2014
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Ingår i: Physics in Medicine and Biology. - : Institute of Physics Publishing (IOPP). - 0031-9155 .- 1361-6560. ; 59:21, s. 6537-6548
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Tidskriftsartikel (refereegranskat)abstract
- Optical coherence tomography (OCT) has been applied for high resolution imaging of articular cartilage. However, the contribution of individual structural elements of cartilage on OCT signal has not been thoroughly studied. We hypothesize that both collagen and chondrocytes, essential structural components of cartilage, act as important light scatterers and that variation in their concentrations can be detected by OCT through changes in backscattering and attenuation. To evaluate this hypothesis, we established a controlled model system using agarose scaffolds embedded with variable collagen concentrations and chondrocyte densities. Using OCT, we measured the backscattering coefficient (µb) and total attenuation coefficient (µt) in these scaffolds. Along our hypothesis, light backscattering and attenuation in agarose were dependent on collagen concentration and chondrocyte density. Significant correlations were found between µt and chondrocyte density (ρ = 0.853, p < 0.001) and between µt and collagen concentration (ρ = 0.694, p < 0.001). µb correlated significantly with chondrocyte density (ρ = 0.504, p < 0.001) but not with collagen concentration (ρ = 0.103, p = 0.422) of the scaffold. Thus, quantitation of light backscattering and, especially, attenuation could be valuable when evaluating the integrity of soft tissues, such as articular cartilage with OCT.
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| 6. |
- Steigen, Terje K., et al.
(författare)
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Randomized study on simple versus complex stenting of coronary artery bifurcation lesions : the Nordic bifurcation study
- 2006
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Ingår i: Circulation. - 0009-7322 .- 1524-4539. ; 114:18, s. 1955-1961
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Tidskriftsartikel (refereegranskat)abstract
- Background - The optimal stenting strategy in coronary artery bifurcation lesions is unknown. In the present study, a strategy of stenting both the main vessel and the side branch ( MV + SB) was compared with a strategy of stenting the main vessel only, with optional stenting of the side branch ( MV), with sirolimus-eluting stents. Methods and Results - A total of 413 patients with a bifurcation lesion were randomized. The primary end point was a major adverse cardiac event: cardiac death, myocardial infarction, target-vessel revascularization, or stent thrombosis after 6 months. At 6 months, there were no significant differences in rates of major adverse cardiac events between the groups ( MV + SB 3.4%, MV 2.9%; P = NS). In the MV + SB group, there were significantly longer procedure and fluoroscopy times, higher contrast volumes, and higher rates of procedure-related increases in biomarkers of myocardial injury. A total of 307 patients had a quantitative coronary assessment at the index procedure and after 8 months. The combined angiographic end point of diameter stenosis > 50% of main vessel and occlusion of the side branch after 8 months was found in 5.3% in the MV group and 5.1% in the MV + SB group ( P = NS). Conclusions - Independent of stenting strategy, excellent clinical and angiographic results were obtained with percutaneous treatment of de novo coronary artery bifurcation lesions with sirolimus-eluting stents. The simple stenting strategy used in the MV group was associated with reduced procedure and fluoroscopy times and lower rates of procedure-related biomarker elevation. Therefore, this strategy can be recommended as the routine bifurcation stenting technique.
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