Copper is taken up efficiently from albumin and α2-macroglobulin by cultured human cells by more than one mechanism

Ionic copper entering blood plasma binds tightly to albumin and the macroglobulin transcuprein. It then goes primarily to the liver and kidney except in lactation, where a large portion goes directly to the mammary gland. Little is known about how this copper is taken up from these plasma proteins. To examine this, the kinetics of uptake from purified human  albumin and α2-macroglobulin, and the effects of inhibitors, were measured using human hepatic (HepG2) and mammary epithelial (PMC42) cell lines. At physiological concentrations (3–6 µM), both cell types took up copper from these proteins independently and at rates similar to each other and to those for Cu-dihistidine or Cu-nitrilotriacetate (NTA). Uptakes from   α2-macroglobulin indicated a single saturable system in each cell type, but with different kinetics, and 65–80% inhibition by Ag(I) in HepG2 cells but not PMC42 cells. Uptake kinetics for Cu-albumin were more complex and also differed with cell type (as was the case for Cu-histidine and NTA), and there was little or no inhibition by Ag(I). High Fe(II) concentrations (100–500 µM) inhibited copper uptake from albumin by 20–30% in both cell types and that from {alpha}2-macroglobulin by 0–30%, and there was no inhibition of the latter by Mn(II) or Zn(II). We conclude that the proteins mainly responsible for the plasma-exchangeable copper pool deliver the metal to mammalian cells efficiently and by several different mechanisms.α2-Macroglobulin delivers it primarily to copper transporter 1 in hepatic cells but not mammary epithelial cells, and additional as-yet-unidentified copper transporters or systems for uptake from these proteins remain to be identified.

Patient safety ethics and human error management in ED contexts part I : development of the global patient safety movement

In recent years there has been increasing recognition internationally that health care is not as safe as it ought to be and that patient safety outcomes need to be improved. To this end patient safety has become the focus of a world-wide endeavour aimed at reducing the incidence and impact of preventable human errors and related adverse events in health care domains. The emergency department has been identified as a significant site of preventable human errors and adverse events in the health care system, raising important questions about the nature of human error management and patient safety ethics in rapidly changing environments. In this article (the first of a two-part discussion on the subject) an overview of the incidence and impact of preventable adverse events in ED contexts is explored. The development of a ‘culture of safety’ in other hazardous industries and the ‘lessons learned’ and applied to the health care industry are also briefly examined. In a second article (to be presented as Part II), some of the ethical tensions that have arisen in the context of implementing patient safety processes and their possible implications for ED contexts are explored.

Patient safety ethics and human error management in ED contexts Part II : Accountability and the challenge to change

In recent years there has been increasing recognition internationally that health care is not as safe as it ought to be and that patient safety outcomes need to be improved. To this end, patient safety has become the focus of a world-wide endeavour – endorsed by the World Health Organisation – to reduce the incidence and impact of preventable human errors and related adverse events in health care domains. The emergency department has been identified as a significant site of preventable human errors and adverse events in the health care system, raising important questions about the nature of human error management and patient safety ethics in rapidly changing environments, of which the Emergency Department is a prime example. In Part I of this article series, an overview of the incidence and impact of preventable adverse events in Emergency Department contexts and the development of the global patient safety movement was presented. In this second article brief attention is given to examining some of the ethical tensions that have arisen in response to the patient safety movement and their possible implications for Emergency Department contexts and staff.

Studies of the human lymphocyte P2Z receptor and its activation of phospholipase D

Extracellular adenosine 5′-triphosphate (ATP) is an agonist for the P2Z receptor of human leukaemic lymphocytes and opens a Ca ²⁺-selective ion channel, which also conducts Ba²⁺, Sr²⁺ and the small fluorescent dye, ethidium⁺. A wide range of receptor agonists, many of which raise cytosolic [Ca²⁺] activate phospholipase D (PLD). In the present study, it was shown that both ATP and 3′-O-(4-benzoylbenzoyl)-ATP (BzATP) stimulated PLD activity in a concentration-dependent manner, and the inhibitory effects of suramin, oxidised ATP, extracellular Na⁺ and Mg²⁺ suggested that the effect of these agonists is mediated by P2Z receptors. The role of divalent cations in ATP-stimulated PLD activity was investigated. Several agonists (eg ATP, thapsigargin, ionomycin) stimulated a rise in cytosolic [Ca²⁺] in human lymphocytes, but only ATP and ionomycin stimulated PLD activity. When Ca²⁺ influx was prevented by EGTA, the majority of ATP-stimulated and all of ionomycin-stimulated PLD activity was inhibited. Preloading cells with the Ca²⁺ chelator, BAPTA, reduced cytosolic [Ca²⁺] and, paradoxically, ATP-stimulated PLD activity was potentiated. ATP-stimulated PLD activity was supported by both Ba²⁺ and Sr²⁺ when they were substituted for extracellular Ca²⁺. Furthermore, both ATP-stimulated PLD activity and ATP-stimulated ¹³³Ba²⁺ influx showed a linear dependence on extracellular [Ba²⁺]. Thus it was concluded that ATP stimulated PLD activity in direct proportion to the influx of divalent cations through the P2Z ion channel and this PLD activity was insensitive to changes in bulk cytosolic [Ca²⁺]. The calmodulin (Ca²⁺/CaM) inhibitor, trifluoperazine (TFP) inhibited ionomycin- and ATP-stimulated PLD activity and ATP-stimulated apoptosis, but had no effect on PLD activity already activated by ATP. However, TFP inhibited ATP-stimulated Ca²⁺, Ba²⁺ and ethidium⁺ fluxes, at concentrations below those which inhibit Ca²⁺/CaM, suggesting that TFP inhibits the P2Z receptor. Similarly, the isoquinolinesulphonamide, KN-62, a selective inhibitor of Ca²⁺/CaM-dependent protein kinase II (CaMKII), also prevented ATP-stimulated apoptosis, but had no effect on pre-activated PLD. In addition, KN-62, and an analogue, KN-04, which has no effect on CaMKII, potently inhibited ATP-stimulated Ba²⁺ influx (IC₅₀ 12.7 ± 1.5 and 17.3 ± 2.7 nM, respectively), ATP-stimulated ethidium⁺ uptake (IC₅₀ 13.1 ± 2.6 and 37.2 ± 8.9 nM, respectively), ATP-stimulated phospholipase D activity (50% inhibition 5.9 ± 1.2 and 9.7 ± 2.8 nM, respectively) and ATP-induced shedding of the surface adhesion molecule, L-selectin (IC₅₀ 31.5 ± 4.5 and 78.7 ± 10.8 nM, respectively). They did not inhibit phorbol ester- or ionomycin-stimulated PLD activity or phorbol ester-induced L-selectin shedding. Neither KN-62 nor KN-04 (both 500 nM) have any effect on UTP-stimulated Ca²⁺ transients in fura-2-loaded human neutrophils, a response which is mediated by the P2Y₂ receptor, neither did they inhibit ATP-stimulated contractile responses mediated by the P2X₁ receptor of guinea pig urinary bladder. Thus, KN-62 and KN-04 are almost equipotent as P2Z inhibitors with IC₅₀s in the nanomolar, indicating that their actions cannot be due to CaMKII inhibition, but rather that they are potent and direct inhibitors of the P2Z receptor. Extracellular ATP-induced shedding of L-selectin from lymphocytes into the medium is a Ca²⁺-independent response. L-selectin is either cleaved by a metalloproteinase or a PLD with specificity for glycosylphosphatidylinositol (GPI). The novel hydroxamic acid-based zinc chelator, Ro-31-9790 blocks ATP-induced L-selectin shedding, but was without effect on ATP-induced Ba²⁺ influx or ATP-stimulated PLD activity. Furthermore, another zinc chelator, 1,10-phenanthroline, an inhibitor of a GPI-PLD, potentiated rather than inhibited ATP-stimulated PLD activity, suggesting that ATP-induced L-selectin shedding and ATP-stimulated PLD activity are independent of each other. Although extracellular ATP is the natural ligand for the lymphocyte P2Z receptor, it is less potent than BzATP in stimulating Ba²⁺ influx. Concentration-response curves for BzATP- and ATP-stimulated ethidium⁺ influx gave EC₅₀s 15.4 ± 1.4 µM and 85.6 ± 8.8 µM, respectively. The maximal response to ATP was only 69.8 ± 1.9% of that for BzATP. Hill coefficients were 3.17 ± 0.24 and 2.09 ± 0.45 for BzATP and ATP respectively, suggesting greater positive cooperativity for BzATP than for ATP in opening the P2Z-operated ion channel. A rank order of agonist potency of BzATP > ATP = 2MeSATP > ATPγS was observed for agonist-stimulated ethidium⁺ influx, while maximal influxes followed a rank order of BzATP > ATP > 2MeSATP > ATPγS. When ATP (300 -1000 µM) was added simultaneously with 30 µM BzATP (EC₉₀), it reduced both ethidium⁺ and Ba²⁺ fluxes by 30 - 40% relative to values observed with BzATP alone. KN-62, previously shown to be a specific inhibitor of the lymphocyte P2Z receptor, was a less potent antagonist of BzATP-induced fluxes than ATP, when maximal concentrations of both agonists (50 and 500 µM respectively) were used. However, when BzATP (18 µM) was used at a concentration equiactive with a maximally effective ATP concentration, KN-62 showed the same inhibitory potency for both agonists. The ecto-ATPase antagonist, ARL-67156, inhibited both ATP- and BzATP-stimulated Ba²⁺ influx, suggesting that the lower efficacy of ATP compared with BzATP was not due to preferential hydrolysis of ATP. Thus, the natural ligand, ATP, is a partial agonist for the P2Z receptor while BzATP is a full agonist. Moreover the competitive studies show that only a single class of P2-receptor (P2Z class) is expressed on human leukaemic lymphocytes. Both ATP- and BzATP-stimulated PLD activity were significantly inhibited (P < 0.05) when cells were suspended in iso-osmotic choline Cl medium. Choline⁺ was found to be a permeant for the P2Z ion channel, since ATP induced a large uptake of [¹⁴C]choline⁺ (60 to 150 µmol/ml intracellular water) during a 5 min incubation, which remained in the cells for several hours, and ATP was used to load cells with these levels of choline⁺. Intracellular choline⁺ inhibited ATP-, BzATP-, PMA- and ionomycin-stimulated PLD activity. Brief exposure of lymphocytes to ATP increased the subsequent basal rate of ethidium⁺ uptake, and this was prevented by intracellular choline⁺. It is proposed that P2Z-mediated Ca²⁺ influx in lymphocytes activates PLD leading to significantly changes of the phospholipid composition of the plasma membrane, which subsequently produces a permeability lesion, which in turn contributes to cell death.

Policy, practice and purpose in the field of education : a critical review

This paper provides a critical review of papers in this special issue on Bourdieu and practice. What is different about this collection is that, in analysing policy and practice through a Bourdieusian lens, the thinking tools of field, disposition (collective and individual), logics of practice and doxa have been mobilised with regard to the social practices of educational policy - its production, circulation and reception. First, these papers illustrate how, as a field, education has its own language, boundaries and power relations informed by particular modes of distinction and legitimation around different forms of capital formation, thus providing explanations for both social mobility and social stratification. Second, this collection foregrounds 'policy as practice' in terms of the social practices involved in the production of policy, the practices involved with the articulation and vernacularisation of policy through the processes of its reception, as well as the intent and effects of policy changing practice. Third, in focusing on specific policy problematics in higher education and schools, teacher professional development, leadership and educational reform, these contributions illustrate multiple methodological approaches as to how Bourdieu's thinking tools can be used to theorise educational policy, change, practice and effects. The value of Bourdieu's work lies on getting past the impasses between divisions between material and cultural analyses, between the materialist and linguistic focus, by talking about social practices, what people are doing, how they are thinking and how they are acting.

The relationship between human beings and technological systems

By combining the ontological approaches to technology of Dessauer, Ortega y Gasset and Heidegger, with the psychology of Jung, the integrated and psycho-constructivist approach to technology demonstrates that the relationship between human beings and technological systems is a symptomatic, symbiotic and synchronistic factor of human well-being and adaption.

Primary teacher beliefs and practices in working and thinking scientifically and technologically

What are primary teachers' beliefs about thinking and working scientifically and technologically? How do the teachers' beliefs manifest in classroom practice? What differences do the teachers see between thinking and working scientifically and technologically? These questions were central themes of the case study research. Interviews and classroom observation were the techniques used to identify how three experienced primary teachers' beliefs about thinking and working technologically and scientifically were manifested in their classroom practice.

Historical landscape languages : creating symbolic space over generations

Landscape creation takes time, patience, water, and languages of visions. Landscape ‘history’ is not short in time but progressive, evolutionary and slow. In the case of the Adelaide Park Lands, the spectre of the myth of the Park Lands as a historical statement is very evident in planning and design discourses in South Australia. It is a mental creation of a number of actors who sought initially to remove all vegetation and evidence of human sedentary occupation. These actors applied languages to argue for a certain type of landscape as well as for the human, water, plant and financial resources to construct this picture. Some were simple letters to editors, some were political statements and pronouncements, some were the actual endeavours and expressions of municipal officials and city gardeners who sought to plant and craft representations of what they thought were ideal visions, and some were consultants who equally sought to apply their ideals.

This paper considers the historiography of the Adelaide Park Lands through the languages of those who argued for and enabled its planting using their words, languages and action examples.

Nursing and justice as a basic human need

This paper explores the idea that justice is a basic human need akin to those famously depicted in Maslow’s hierarchy of human needs and, as such, warrants recognition as a core element in representative ideas about nursing. Early nurse theorists positioned the principles and practice of nursing as having their origins in ‘universal human needs’. The principle of deriving nursing care from human needs was thought to provide a guide not only for promoting health, but for preventing disease and illness. The nursing profession has had a longstanding commitment to social justice as a core professional value and ideal, obligating nurses to address the social conditions that undermine people’s health.The idea of justice as a universal human need per se and its possible relationship to people’s health outcomes has, however, not been considered. One reason for this is that justice in nursing discourse has more commonly been associated with law and ethics, and the legal and ethical responsibilities of nurses in relation to individualized patient care and, more recently, changing systems of care to improve health and health outcomes. Although this association is not incorrect, it is incomplete.A key aim of this paper is to redress this oversight and to encourage a broader conceptualization of justice as necessary for human survival, health and development, not merely as a professional value, or legal or ethical principle for guiding human conduct.

Social work and welfare education without discrimination : are we there yet?

The Australian Human Rights Commission (AHRC) has identified education as one of five crucial issues relating to the settlement of African Australians into the Australian community from a human rights perspective (AHRC 2009:5). In this paper I advocate that social work and welfare work in Australia are placed in important and multi dimensioned positions in relation to our complicities, responsibilities and potentialities with this educational human rights issue. As a Technical and Further Education (TAFE) welfare and University social work educator, I offer an outline of the ‘mutual respect inquiry approach’ that developed between myself and Southern Sudanese Australian students as a basis for discussion, reflection and change. I seek to stimulate thinking and action, particularly among those welfare work and social work educators, practitioners and students who identify as critical and anti-oppressive, to consider how these approaches can be realised and reshaped in practice to enhance not only Southern Sudanese Australians' right to education that is 'without discrimination', but indeed all students in our diversity.

Human rights and the right to development : insights into the Myanmar government's response to rights allegations

Myanmar is ruled by a military government that is strongly condemned for human rights abuses. In responding to these allegations, the Myanmar government repeatedly adopt the language of Right to Development as a counter perspective and counter allegation. The Right to Development is not well reflected in the Western human rights discourse, and both its development and Myanmar's position in the Right to Development dialogue are considered. This paper looks at the differing perspective that an understanding of the official public Myanmar response to rights allegations brings to the human rights debate surrounding Myanmar, highlighting contested ideas concerning the identity of rights duty-bearers, conceptions of those duties, and allegations of double standards. While the Myanmar position that sanctions violate the Right to Development is rejected, it is suggested that this difference in perspective is a contributor to the impasse and communication gap between the West and the Myanmar regime over human rights.

Dignity and human rights in correctional practice

Interventions with offenders have a normative layer as well as a scientific basis and therefore it is not possible to quarantine ethical questions from discussions of best practice. My aim in this paper is to provide an expanded ethical canvass from which to approach correctional practice with offenders. The cornerstone of this broader ethical perspective will be the concept of human dignity and its protection by human rights norms and theories. I also explore the relationship between responses to crime and offender rehabilitation based on an enriched theory of punishment that is sensitive to offenders’ moral equality and their attendant rights.

Human rights and correctional clinical practice

The formulation of human rights theory and policies represents an ethical advance and promises to supply a framework for resolving ethnic, social, and individual conflicts. Ethics is essentially a means for coordinating the conflicting interests of peoples and nations and human rights provide a strong foundation to do this in multiple domains. Our aim in this paper is to apply a human rights perspective, in association with a justifying theory and set of goods, to the correctional arena. First, we discuss the definition of human rights, their proper analysis and justification. We then apply the results of our discussion to the assessment, treatment, and monitoring of offenders. Finally, we consider the policy, research, and intervention implications of a human rights perspective for correctional practitioners.

Amyloid formation in human IAPP transgenic mouse islets and pancreas, and human pancreas, is not associated with endoplasmic reticulum stress

Aims/hypothesis Supraphysiological levels of the amyloidogenic peptide human islet amyloid polypeptide have been associated with beta cell endoplasmic reticulum (ER) stress. However, in human type 2 diabetes, levels of human IAPP are equivalent or decreased relative to matched controls. Thus, we sought to investigate whether ER stress is induced during amyloidogenesis at physiological levels of human IAPP.

Methods Islets from human IAPP transgenic mice that develop amyloid, and non-transgenic mice that do not, were cultured for up to 7 days in 11.1, 16.7 and 33.3 mmol/l glucose. Pancreases from human IAPP transgenic and non-transgenic mice and humans with or without type 2 diabetes were also evaluated. Amyloid formation was determined histologically. ER stress was determined in islets by quantifying mRNA levels of Bip, Atf4 and Chop (also known as Ddit3) and alternate splicing of Xbp1 mRNA, or in pancreases by immunostaining for immunoglobulin heavy chain-binding protein (BIP), C/EBP homologous protein (CHOP) and X-box binding protein 1 (XBP1).

Results Amyloid formation in human IAPP transgenic islets was associated with reduced beta cell area in a glucose- and time-dependent manner. However, amyloid formation was not associated with significant increases in expression of ER stress markers under any culture condition. Thapsigargin treatment, a positive control, did result in significant ER stress. Amyloid formation in vivo in pancreas samples from human IAPP transgenic mice or humans was not associated with upregulation of ER stress markers.

Conclusions/interpretation Our data suggest that ER stress is not an obligatory pathway mediating the toxic effects of amyloid formation at physiological levels of human IAPP.

The role of contexts and teacher's questioning to enhance students' thinking

This paper discusses results from a design research in line with Realistic Mathematics Education (RME). Daily cycles of design, classroom experiments, and retrospective analysis are enacted in five days of working about division by fractions. Data consists of episodes of video classroom discussions, and samples of students’ work. The focus of discussion and analysis centres on the role of contexts and the role of teachers’ probing questions to elicit students’ thinking. Our findings suggest that contexts that are meaningful for and understandable by students bring out rich mathematical thinking and discussion amongst students. Meaningful contexts combined with teacher’s probing questions - highlighting big mathematical ideas - allow students to attain various approaches at different levels of formal mathematics.