20 research outputs found
BAAV Transcytosis Requires an Interaction with ÎČ-1-4 Linked- Glucosamine and gp96
Cell surface carbohydrates play an important role in virus entry and intracellular trafficking. Bovine Adeno-Associated Virus (BAAV) uses plasma membrane gangliosides for transduction and infection. In addition, independent of the infectious pathway, BAAV also has the ability to pass through barrier epithelia and endothelia using a transcytosis pathway dependent upon the presence of cell surface carbohydrates. Thus, in order to better define the carbohydrate interactions that are necessary for BAAV infection or transcytosis, a glycan microarray composed of both natural and synthetic carbohydrates was probed with HA-tagged BAAV particles. This identified chitotriose, a trimer of ÎČ-1-4-linked N-acetyl glucosamine, as having an interaction with BAAV. Competition experiments showed that the BAAV interaction with this carbohydrate is not necessary for infection but is instead important in the transcytosis pathway. The ÎČ-1-4-linked N-acetyl glucosamine modification has been reported on gp96, a glycoprotein involved in the transcytosis of bacteria and toxins. Significantly, immunoprecipitation and competition experiments with an anti-gp96 antibody and a soluble form of gp96, respectively, showed this glycoprotein can also interact with BAAV to serve as a receptor for its transcytosis
Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases
The production of peroxide and superoxide is an inevitable consequence of
aerobic metabolism, and while these particular "reactive oxygen species" (ROSs)
can exhibit a number of biological effects, they are not of themselves
excessively reactive and thus they are not especially damaging at physiological
concentrations. However, their reactions with poorly liganded iron species can
lead to the catalytic production of the very reactive and dangerous hydroxyl
radical, which is exceptionally damaging, and a major cause of chronic
inflammation. We review the considerable and wide-ranging evidence for the
involvement of this combination of (su)peroxide and poorly liganded iron in a
large number of physiological and indeed pathological processes and
inflammatory disorders, especially those involving the progressive degradation
of cellular and organismal performance. These diseases share a great many
similarities and thus might be considered to have a common cause (i.e.
iron-catalysed free radical and especially hydroxyl radical generation). The
studies reviewed include those focused on a series of cardiovascular, metabolic
and neurological diseases, where iron can be found at the sites of plaques and
lesions, as well as studies showing the significance of iron to aging and
longevity. The effective chelation of iron by natural or synthetic ligands is
thus of major physiological (and potentially therapeutic) importance. As
systems properties, we need to recognise that physiological observables have
multiple molecular causes, and studying them in isolation leads to inconsistent
patterns of apparent causality when it is the simultaneous combination of
multiple factors that is responsible. This explains, for instance, the
decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference
The antecedents of simultaneous appointments to CEO and Chair
Duality, Succession, Corporate governance,
Revisiting agency theory: evidence of board independence and agency cost from Bangladesh
This study examines the influence of board independence on firm agency cost among listed firms in Bangladesh, which feature concentrated ownership and high insider representation on corporate boards. This study uses three measures of agency cost: the 'expense ratio', the 'Q-free cash flow interaction' and the 'asset utilization ratio'. The finding of the study is that board independence can reduce the firm agency cost only under 'asset utilization ratio' measure of agency cost. These findings are robust to several robustness tests. Furthermore, the non-linearity tests suggest that the benefit of outside independent directors is generally plausible as a factor controlling agency costs in the case of a medium level of board independence. Overall, these findings do not reject the validity of agency theory, supporting the Anglo-American orthodoxy promoting outside independent directors as good monitors
Corporate governance decision-making model: How to nominate skilled board members, by addressing the formal and informal systems
Proton Beam Radiation Therapy for Prostate CancerâIs the Hype (and the Cost) Justified?
Corporate Governance and Sustainability Performance: Analysis of Triple Bottom Line Performance
The study empirically investigates the relationship between corporate governance and the triple bottom line sustainability performance through the lens of agency theory and stakeholder theory. We claim, in fact, that no single theory fully accounts for all the hypothesised relationships. We measure sustainability performance through manual content analysis on sustainability reports of the US-based companies. The study extends the existing literature by investigating the impact of selected corporate governance mechanisms on each dimension of sustainability performance, as defined by the GRI framework. Our approach allows to identify which governance mechanisms foster triple bottom line performance, also revealing that some mechanisms fit only specific dimension(s) of sustainability. The fact-based findings provide support for a new beginning in the theorising process in which the theories must try not only to provide rationale for the impact of corporate governance on sustainability, but also to explain which dimension of sustainability might be more affected. The most important implication for practitioners is the support for sustainability practices, which may be gained through implementation of particular corporate governance mechanisms. The findings contribute also to the improvement of the ongoing standard setting process, in particular as it concerns the in-depth revision of the economic dimension of sustainability carried out under the new GRI framework