T1-Enhanced MRI-visible nanoclusters for imaging-guided drug delivery

Iron oxide nanoparticles with extremely low dimensions have recently been explored as positive (T₁) contrast agent for magnetic resonance imaging (MRI). However, their small sizes lead to fast renal clearance and limit their use in elongated in vivo tracking or therapy monitoring. In this paper, we present a state of art approach to forming nanoclusters by crosslinking ultrasmall iron oxide nanoparticles with bovine serum albumin. This novel design not only maintains the T₁ performance of the ultrasmall nanoparticles, but also significantly increases their blood circulation times from 15 minutes to over two hours. Our breast tumor model study also exhibited enhanced contrast at tumor sites for more than 24 hours. The ability of maintaining the T₁ performance of the ultrasmall nanoparticles is significant, because previous studies have shown complete T₁ loss or signal decrease upon polymer encapsulation. This design also shows great potential in encapsulating model drug molecules, which will greatly benefit the field of imaging-guided drug delivery.

The impact of indigenous cultural identity and cultural engagement on violent offending

BACKGROUND

Possessing a strong cultural identity has been shown to protect against mental health symptoms and buffer distress prompted by discrimination. However, no research to date has explored the protective influences of cultural identity and cultural engagement on violent offending. This paper investigates the relationships between cultural identity/engagement and violent recidivism for a cohort of Australian Indigenous people in custody.

METHODS

A total of 122 adults from 11 prisons in the state of Victoria completed a semi-structured interview comprising cultural identification and cultural engagement material in custody. All official police charges for violent offences were obtained for participants who were released from custody into the community over a period of 2 years.

RESULTS

No meaningful relationship between cultural identity and violent recidivism was identified. However a significant association between cultural engagement and violent recidivism was obtained. Further analyses demonstrated that this relationship was significant only for participants with a strong Indigenous cultural identity. Participants with higher levels of cultural engagement took longer to violently re-offend although this association did not reach significance.

CONCLUSIONS

For Australian Indigenous people in custody, 'cultural engagement' was significantly associated with non-recidivism. The observed protective impact of cultural engagement is a novel finding in a correctional context. Whereas identity alone did not buffer recidivism directly, it may have had an indirect influence given its relationship with cultural engagement. The findings of the study emphasize the importance of culture for Indigenous people in custody and a greater need for correctional institutions to accommodate Indigenous cultural considerations.

Genetic and environmental factors influence Listeria monocytogenes nisin resistance

AIMS

Listeria monocytogenes nisin resistance increases when first exposed to NaCl and other stresses, such as low pH. In addition to environmental stressors, specific genomic elements can confer nisin resistance, such as the stress survival islet (SSI-1). As SSI-1 is variably present among L. monocytogenes strains, we wanted to determine if SSI-1 was associated with salt-induced nisin resistance.

METHODS AND RESULTS

The presence of SSI-1 was determined using PCR for 48 strains of L. monocytogenes. When combined with multilocus sequence typing data, we found that the distribution of SSI-1 is clonal, where strains from clonal complexes (CC) 2, 6 and 11 do not have SSI-1, while strains from CCs 3, 5, 7 and 9 contain SSI-1. The impact of SSI-1 on salt-induced nisin resistance was dependent on CC. The average log decrease after 24 h of exposure to nisin at 7°C under salt-inducing conditions was 2·6 ± 1·1 for CC 9 strains and 2·3 ± 0·7 for CC 11 strains, which had significantly lower survival compared to the other CCs, such as 1·3 ± 0·3 for CC 6. Deletion of SSI-1 from a CC 7 strain demonstrated the role SSI-1 plays in salt-induced nisin resistance, as the deletion mutant had lower resistance compared to the parent strain.

CONCLUSIONS

These data suggest that inducible nisin resistance in L. monocytogenes can be influenced by environmental conditions as well as the genetic composition of the strain, which should be considered when selecting control measures for ready-to-eat foods.

SIGNIFICANCE AND IMPACT OF THE STUDY

The foodborne pathogen L. monocytogenes can grow in suboptimal conditions, including low temperature and high osmolarity, which makes it a safety concern for ready-to-eat foods. When using antimicrobial peptide inhibitors such as nisin, it is important to understand how food components can impact antimicrobial resistance across the genetic diversity of L. monocytogenes.

Shape-dependent cellular behaviors and relaxivity of iron oxide-based T1 MRI contrast agents

Recent research efforts about iron oxide nanoparticles has focused on the development of iron oxide-based T₁ contrast agents for magnetic resonance imaging (MRI), such as ultrasmall iron oxide nanospheres (USNPs <4 nm) and ultrathin nanowires (NW, diameter <4 nm). In this paper, we report the cellular uptake behaviors of these two types of ultrasmall scale nanostructures on HepG2 cells. Both these two nanostructures were functionalized with tannic acid and their physical and chemical properties were carefully analyzed before cellular tests. Both USNPs and NWs exhibited strong paramagnetic signals, a property suitable for T₁ MRI contrast agents. The distinct shapes also caused much difference in their cellular uptake behaviors. Specifically, the uptake of USNPs was five times higher than that of NWs after 72 hours incubation. The shape-dependent cellular uptake can potentially lead to different blood circulation times, and subsequently different applications of these two types of ultrasmall nanostructures.

REM

The well-documented health disparities between the Australian Indigenous and non-Indigenous population mandates a comprehensive response from health professionals. This article outlines the approach taken by one faculty of health in a large urban Australian university to enhance cultural competence in students from a variety of fields. Here we outline a collaborative and deeply respectful process of Indigenous and non-Indigenous university staff collectively developing a model that has framed the embedding of a common faculty Indigenous graduate attribute across the curriculum. Through collaborative committee processes, the development of the principles of “Respect; Engagement and sharing; Moving forward” (REM) has provided both a framework and way of “being and doing” our work. By drawing together the recurring principles and qualities that characterize Indigenous cultural competence the result will be students and staff learning and bringing into their lives and practice, important Indigenous cultural understanding.

An assessment of the doses received by members of the public in Japan following the nuclear accident at Fukushima Daiichi nuclear power plant

The earthquake and tsunami on 11 March 2011, centred off the east coast of Japan, caused considerable destruction and substantial loss of life along large swathes of the Japanese coastline. The tsunami damaged the Fukushima Daiichi nuclear power plant (NPP), resulting in prolonged releases of radioactive material into the environment. This paper assesses the doses received by members of the public in Japan. The assessment is based on an estimated source term and atmospheric dispersion modelling rather than monitoring data. It is evident from this assessment that across the majority of Japan the estimates of dose are very low, for example they are estimated to be less than the annual average dose from natural background radiation in Japan. Even in the regions local to Fukushima Daiichi NPP (and not affected by any form of evacuation) the maximum lifetime effective dose is estimated to be well below the cumulative natural background dose over the same period. The impact of the urgent countermeasures on the estimates of dose was considered. And the relative contribution to dose from the range of exposure pathways and radionuclides were evaluated. Analysis of estimated doses focused on the geographic irregularity and the impact of the meteorological conditions. For example the dose to an infant's thyroid received over the first year was estimated to be greater in Hirono than in the non-evacuated region of Naraha, despite Hirono being further from the release location. A number of factors were identified and thought to contribute towards this outcome, including the local wind pattern which resulted in the recirculation of part of the release. The non-uniform nature of dose estimates strengthens the case for evaluations based on dispersion modelling.

The role of primary health care services to better meet the needs of Aboriginal Australians transitioning from prison to the community

Background

Aboriginal Australians are more likely than other Australians to cycle in and out of prison on remand or by serving multiple short sentences—a form of serial incarceration and institutionalisation. This cycle contributes to the over-representation of Aboriginal Australians in prison and higher rates of recidivism. Our research examined how primary health care can better meet the health care and social support needs of Aboriginal Australians transitioning from prison to the community.

Methods

Purposive sampling was used to identify 30 interviewees. Twelve interviews were with Aboriginal people who had been in prison; ten were with family members and eight with community service providers who worked with former inmates. Thematic analysis was conducted on the interviewees’ description of their experience of services provided to prisoners both during incarceration and on transition to the community.

Results

Interviewees believed that effective access to primary health care on release and during transition was positively influenced by providing appropriate healthcare to inmates in custody and by properly planning for their release. Further, interviewees felt that poor communication between health care providers in custody and in the community prior to an inmate’s release, contributed to a lack of comprehensive management of chronic conditions. System level barriers to timely communication between in-custody and community providers included inmates being placed on remand which contributed to uncertainty regarding release dates and therefore difficulties planning for release, cycling in and out of prison on short sentences and being released to freedom without access to support services.

Conclusions

For Aboriginal former inmates and family members, release from prison was a period of significant emotional stress and commonly involved managing complex needs. To support their transition into the community, Aboriginal former inmates would benefit from immediate access to culturally- responsive community -primary health care services. At present, however, pre-release planning is not always available, especially for Aboriginal inmates who are more likely to be on remand or in custody for less than six months.

Decolonisation: A critical step for improving Aboriginal health

Aboriginal health continues to be in crisis in Australia although expenditure has increased in service provision, strategic planning, research and policy development over the last thirty years. This paper recommends that a shift must occur to make Aboriginal health improvement a reality. This shift requires the decolonising of Aboriginal health so that the experts in Aboriginal health, namely Aboriginal people, can voice and action initiatives that address their health issues. This shift is from the current western dominant approach that continues to manage Aboriginal health in its linear spectrum of illness and disease. Aboriginal people view health differently; their contexts for health issues are also diverse requiring a more holistic and informed response.

Reframing spaces by building relationships: community collaborative participatory action research with Aboriginal mothers in prison

Aboriginal women are vastly over-represented in the Australian prison system. Their recidivism rates are high. Aboriginal women in contact with the criminal justice system also have higher rates of mental health disorders and are likely to have been a victim of violence. The majority of these women are mothers. Their increasing incarceration therefore has serious implications for the health and social and emotional wellbeing of their Aboriginal children, families and communities. Illustrating and exploring this situation requires an Indigenous informed conceptual framework utilising a decolonising research methodology inclusive of enduring community and stakeholder dialogue and consultation. Respectful and ethical praxis are central to this approach. We will describe how this methodology has been applied within a current National Health and Medical Research Council (NHMRC) research project in NSW, Australia. The NHMRC guidelines for research with Aboriginal and Torres Strait Islanders peoples have supported our process and will be highlighted in illustrating our research experience.

Working together to make Indigenous health care curricula everybody's business: a graduate attribute teaching innovation report

Previously there has been commitment to the idea that Indigenous curricula should be taught by Indigenous academic staff, whereas now there is increasing recognition of the need for all academic staff to have confidence in enabling Indigenous cultural competency for nursing and other health professional students. In this way, Indigenous content can be threaded throughout a curriculum and raised in many teaching and learning situations, rather than being siloed into particular subjects and with particular staff. There are many sensitivities around this change, with potential implications for Indigenous and non-Indigenous students and staff, and for the quality of teaching and learning experiences. This paper reports on a collaborative process that was used to reconceptualise how Indigenous health care curricula would be positioned throughout a programme and who would or could work with students in this area. Effective leadership, establishing a truly collaborative environment, acknowledging fears and perceived inadequacies, and creating safe spaces for sharing and learning were crucial in effecting this change.

Who is not coping with colonization? Laying out the map for decolonization

OBJECTIVE

This paper explores reasons for using decolonization as a method for improving Indigenous health status. Decolonization is a method required to shift the current paradigm of Western dominance and colonial amnesia that constructs and maintains Indigenous poor health status.

CONCLUSION

Decolonization requires every Australian to examine the impact colonization has upon their past and present in order to formulate a future that does not reinstate the past. To take these steps requires a balance of histories, informing our current political and social context, critical reflexive practice and open communication with Aboriginal and Torres Strait Islander peoples.