Search

This article provides a comparative analysis of Jihadist foreign fighters who traveled from Australia and Canada to engage in the conflict in Syria and Iraq. Data are provided on the demographics of those who traveled, group affiliations, when and how they traveled, and their social connections. Despite the strong similarities between these societies, significant differences are detected across levels of educational attainment, immediate familial status, and the degree of connection to existing Jihadist networks. The Australian and Canadian foreign fighters also differ, in key respects, from their European counterparts, and even those from the United States. Consideration is given to the possible significance of these differences, as well as the possible return of those currently detained in the region. [ABSTRACT FROM AUTHOR]

Copyright of Annals of Burns & Fire Disasters is the property of Euro-Mediterranean Council for Burns & Fire Disasters and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Neuronal damage following stroke or neurodegenerative diseases is thought to stem in part from overexcitation of N-methyl-D-aspartate (NMDA) receptors by glutamate. NMDA receptors triggered neurotoxicity is mediated in large part by activation of neuronal nitric oxide synthase (nNOS) and production of nitric oxide (NO). Simultaneous production of superoxide anion in mitochondria provides a permissive environment for the formation of peroxynitrite (ONOO−). Peroxynitrite damages DNA leading to strand breaks and activation of poly(ADP-ribose) polymerase-1 (PARP-1). This signal cascade plays a key role in NMDA excitotoxicity, and experimental models of stroke and Parkinson''s disease. The mechanisms of PARP-1-mediated neuronal death are just being revealed. While decrements in ATP and NAD are readily observed following PARP activation, it is not yet clear whether loss of ATP and NAD contribute to the neuronal death cascade or are simply a biochemical marker for PARP-1 activation. Apoptosis-inducing factor (AIF) is normally localized to mitochondria but following PARP-1 activation, AIF translocates to the nucleus triggering chromatin condensation, DNA fragmentation and nuclear shrinkage. Additionally, phosphatidylserine is exposed and at a later time point cytochrome c is released and caspase-3 is activated. In the setting of excitotoxic neuronal death, AIF toxicity is caspase independent. These observations are consistent with reports of biochemical features of apoptosis in neuronal injury models but modest to no protection by caspase inhibitors. It is likely that AIF is the effector of the morphologic and biochemical events and is the commitment point to neuronal cell death, events that occur prior to caspase activation, thus accounting for the limited effects of caspase inhibitors. There exists significant cross talk between the nucleus and mitochondria, ultimately resulting in neuronal cell death. In exploiting this pathway for the development of new therapeutics, it will be important to block AIF translocation from the mitochondria to the nucleus without impairing important physiological functions of AIF in the mitochondria. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a common progressive neurodegenerative disorder caused by the loss of dopaminergic neurons in the substantia nigra. Although mutations in (α-synuclein have been identified in autosomal dominant PD, the mechanism by which dopaminergic neural cell death occurs remains unknown. Proteins encoded by two other genes in which mutations cause familial PD, parkin and UCH-L1, are involved in regulation of the ubiquitin-proteasome pathway, suggesting that dysregulation of the ubiquitin-proteasome pathway is involved in the mechanism by which these mutations cause PD. We established inducible PC12 cell lines in which wild-type or mutant (α-synuclein can be de-repressed by removing doxycycline. Differentiated PC12 cell lines expressing mutant (α-synuclein showed decreased activity of proteasomes without direct toxicity. Cells expressing mutant (α-synuclein showed increased sensitivity to apoptotic cell death when treated with sub-toxic concentrations of an exogenous proteasome inhibitor. Apoptosis was accompanied by mitochondrial depolarization and elevation of caspase-3 and -9, and was blocked by cyclosporin A. These data suggest that expression of mutant (α-synuclein results in sensitivity to impairment of proteasome activity, leading to mitochondrial abnormalities and neuronal cell death. [ABSTRACT FROM AUTHOR]