Purification and characterization of heparan sulfate from human primary osteoblasts

Heparan sulfate (HS) is a linear, highly variable, highly sulfated glycosaminoglycan sugar whose biological activity largely depends on internal sulfated domains that mediate specific binding to an extensive range of proteins. In this study we employed anion exchange chromatography, molecular sieving and enzymatic cleavage on HS fractions purified from three compartments of cultured osteoblasts-soluble conditioned media, cell surface, and extracellular matrix (ECM). We demonstrate that the composition of HS chains purified from the different compartments is structurally non-identical by a number of parameters, and that these differences have significant ramifications for their ligand-binding properties. The HS chains purified of conditioned medium had twice the binding affinity for FGF2 when compared with either cell surface or ECM HS. In contrast, similar binding of BMP2 to the three types of HS was observed. These results suggest that different biological compartments of cultured cells have structurally and functionally distinct HS species that help to modulate the flow of HS-dependent factors between the ECM and the cell surface.

What it means to become a public relations professional: student perceptions of professional identity through real-world learning

Public relations educators need new solutions to prepare students to become tomorrow's practitioner today. Managers and employers in the new creative workforce (McWilliam, 2008) expect graduates to be problem solvers, critical and creative thinkers, reflective, and self reliant (Barrie, 2008; David, 2004). Enabling students to develop these attributes requires a collaborative and creative approach to pedagogy (Jeffrey & Craft, 2001, 2004). A model for the next generation of public relations education was developed to integrate industry partnerships as a way to bridge pedagogy and professional practice. The model suggests (a) that industry partnerships be embedded in learning activities, (b) that assessment items be considered on a continuum and delivered incrementally across a course of study, and (c) that connections between classroom and workplace activities are clearly signposted for students.

Responsibility to Protect and Sovereignty

The responsibility to protect ('R2P') principle articulates the obligations of the international community to prevent conflict occurring, to intervene in conflicts, and to assist in rebuilding after conflicts. The doctrine is about protecting civilians in armed conflicts from four mass atrocity crimes: genocide, war crimes, crimes against humanity and ethnic cleansing. This book examines interventions in East Timor, Sri Lanka, Sudan and Kosovo. The chapters explore and question UN debates with respect to the doctrine both before and after its adoption in 2005; contrasting state attitudes to international military intervention; and what takes place after intervention. It also discusses the ability of the Security Council to access reliable information and credible and transparent processes to enable it to make a determination on the occurrence of atrocities in a Member State. Questioning whether there is a need to find a closer operational link between the responsibilities to prevent and react and a normative link between R2P and principles of international law, the contributions examine the effectiveness of the framework of R2P for international decision-making in response to mass atrocity crimes and ask how an international system to deal with threats and mass atrocities can be developed in the absence of a central authority. This book will be valuable to those interested in international law, human rights, and security, peace and conflict studies