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Purpose: The aim of this study was to investigate in 18 patients with ischaemic stroke classified as cryptogenic and presenting non-stenotic carotid atherosclerotic plaques the morphological and biological aspects of these plaques with magnetic resonance imaging (MRI) and F-fluoro-deoxyglucose positron emission tomography (F-FDG PET) imaging. Methods: Carotid arteries were imaged 150 min after injection of F-FDG with a combined PET/MRI system. American Heart Association (AHA) lesion type and plaque composition were determined on consecutive MRI axial sections ( n = 460) in both carotid arteries. F-FDG uptake in carotid arteries was quantified using tissue to background ratio (TBR) on corresponding PET sections. Results: The prevalence of complicated atherosclerotic plaques (AHA lesion type VI) detected with high-resolution MRI was significantly higher in the carotid artery ipsilateral to the ischaemic stroke as compared to the contralateral side (39 vs 0 %; p = 0.001). For all other AHA lesion types, no significant differences were found between ipsilateral and contralateral sides. In addition, atherosclerotic plaques classified as high-risk lesions with MRI (AHA lesion type VI) were associated with higher F-FDG uptake in comparison with other AHA lesions (TBR = 3.43 ± 1.13 vs 2.41 ± 0.84, respectively; p < 0.001). Furthermore, patients presenting at least one complicated lesion (AHA lesion type VI) with MRI showed significantly higher F-FDG uptake in both carotid arteries (ipsilateral and contralateral to the stroke) in comparison with carotid arteries of patients showing no complicated lesion with MRI (mean TBR = 3.18 ± 1.26 and 2.80 ± 0.94 vs 2.19 ± 0.57, respectively; p < 0.05) in favour of a diffuse inflammatory process along both carotid arteries associated with complicated plaques. Conclusion: Morphological and biological features of high-risk plaques can be detected with F-FDG PET/MRI in non-stenotic atherosclerotic plaques ipsilateral to the stroke, suggesting a causal role for these plaques in stroke. Combined F-FDG PET/MRI systems might help in the evaluation of patients with ischaemic stroke classified as cryptogenic. [ABSTRACT FROM AUTHOR]

ABSTRACT This article investigates how far the International Criminal Court (ICC) trial of post-election violence in Kenya represented a new start for Kenyan politics, for international criminal justice in Africa, and for the international response to democratic violence more broadly. For the first time an international criminal court investigated violence associated with the democratic process. The prosecution of instigators of violence was not only a demonstration of a far less patient international approach to a democratic process gone wrong; it also provided the internationally expected response to exceptional levels of violence in the face of domestic inaction. However, it is less clear whether the ICC case represents a new beginning for Kenya. It might be a new start for political accountability in the context of a weak domestic judiciary, but it cannot address the structural root causes of violence that require political reform rather than criminal prosecution. [ABSTRACT FROM AUTHOR]

Background: Iloprost, a stable prostacyclin I2 analogue, seems to have an osteoblast-protective potential, whereas indomethacin suppresses new bone formation. The aim of this study was to investigate human bone marrow stromal cell (BMSC) proliferation and differentiation towards the osteoblastic lineage by administration of indomethacin and/or iloprost., Material/methods: Human bone marrow cells were obtained from 3 different donors (A=26 yrs/m; B=25 yrs/f, C=35 yrs/m) via vacuum aspiration of the iliac crest followed by density gradient centrifugation and flow cytometry with defined antigens (CD105+/73+/45-/14-). The cells were seeded and incubated as follows: without additives (Group 0; donor A/B/C), with 10(-7) M iloprost only (Group 0+ilo; A/B), with indomethacin only in concentrations of 10(-6) M (Group 1, A), 10(-5) M (Group 2, B), 10(-4) M (Group 3, A/B), and together with 10(-7) M iloprost (Groups 4-6, A/B/C). On Day 10 and 28, UV/Vis spectrometric and immunocytochemical assays (4 samples per group and donor) were performed to investigate cell proliferation (cell count measurement) and differentiation towards the osteoblastic lineage (CD34-, CD45-, CD105+, type 1 collagen (Col1), osteocalcin (OC), alkaline phosphatase (ALP), Runx2, Twist, specific ALP-activity)., Results: Indomethacin alone suppressed BMSC differentiation towards the osteoblastic lineage by downregulation of Runx2, Col1, and ALP. In combination with indomethacin, iloprost increased cell proliferation and differentiation and it completely suppressed Twist expression at Day 10 and 28. Iloprost alone did not promote cell proliferation, but moderately enhanced Runx2 and Twist expression. However, the proliferative effects and the specific ALP-activity varied donor-dependently., Conclusions: Iloprost partially antagonized the suppressing effects of indomethacin on BMSC differentiation towards the osteoblast lineage. It enhanced the expression of Runx2 and, only in the presence of indomethacin, it completely suppressed Twist. Thus, in the treatment of avascular osteonecrosis or painful bone marrow edema, the undesirable effects of indomethacin might be counterbalanced by iloprost.