Assessment of freestanding membranes prepared from Antheraea pernyi silk fibroin as a potential vehicle for corneal epithelial cell transplantation

Freestanding membranes created from Bombyx mori silk fibroin (BMSF) offer a potential vehicle for corneal cell transplantation since they are transparent and support the growth of human corneal epithelial cells (HCE). Fibroin derived from the wild silkworm Antheraea pernyi (APSF) might provide a superior material by virtue of containing putative cell- attachment sites that are absent from BMSF. Thus we have investigated the feasibility of producing transparent, freestanding membranes from APSF and have analysed the behaviour of HCE cells on this material. No significant differences in cell numbers or phenotype were observed in short term HCE cell cultures established on either fibroin. Production of transparent freestanding APSF membranes, however, proved to be problematic as cast solutions of APSF were more prone to becoming opaque, displayed significantly lower permeability and were more brittle than BMSF-membranes. Cultures of HCE cells established on either membrane developed a normal stratified morphology with cytokeratin pair 3/12 being immuno-localized to the superficial layers. We conclude that while it is feasible to produce transparent freestanding membranes from APSF, the technical difficulties associated with this biomaterial, along with an absence of enhanced cell growth, currently favours the continued development of BMSF as a preferred vehicle for corneal cell transplantation. Nevertheless, it remains possible that refinement of techniques for processing APSF might yet lead to improvements in the handling properties and performance of this material.

The promise of justice reinvestment

Abstract: This article examines the notion and practice of Justice Reinvestment (‘JR’), an emerging approach addressing the high social and economic costs of soaring incarceration rates. JR invests in public safety by reallocating dollars from corrections budgets to finance education, housing, healthcare, and jobs in high-crime communities. Key distinguishing features of JR (including justice and asset mapping, budgetary devolution and localism, and the desirability of bipartisanship) are briefly outlined, followed by discussion of its recent emergence and application in the United States, and to a lesser extent in the United Kingdom. The prospects for the adoption of JR approaches in Australia are then considered, with particular reference to the high imprisonment rates of Indigenous people. If JR is to be promoted in the Australian context it is important that it be subject to critical scrutiny and therefore some of the key problems are briefly outlined, before a conclusion which emphasizes the potential benefits of JR.

The importance of understanding student learning styles in accounting degree programs

Accounting education is critical and any improvements in tertiary education of accounting students should result in better prepared graduates entering the profession. This study evaluates accounting students’ learning styles and the interaction of learning styles and teaching methodologies during degree programmes. Nine classes of accounting students (648 students) spread across four years and two degree programmes were evaluated. Students self-evaluated their learning style, pre-instruction. They were then subject to two separate teaching techniques (one active and one passive) in each course. Learning styles were then re-assessed and teaching techniques evaluated. Accounting students displayed a preference for passive learning, even those far advanced in their degrees. Furthermore, when learning styles matched teaching methods used, usefulness was assessed as high but when learning styles and teaching methods differed, usefulness deteriorated. Overall, the teaching methods were deemed more effective by active rather than passive learners. The implications are significant. To maximise educational benefit for the accounting profession, student learning styles should be assessed before designing appropriate teaching methodologies. This has resource implications which would have to be considered.

“Best for everyone concerned” or “Only as a last resort”? Views of Australian doctors about sterilisation of men and women with intellectual disability

Background  Doctors have the potential to influence opportunities for normative life experiences in the area of sexuality for individuals with intellectual disability (ID). Method  In Study One, 106 doctors completed the Attitudes to Sexuality Questionnaire (Individuals with an Intellectual Disability). In Study Two, 97 doctors completed a modified form of the questionnaire that included additional questions designed to assess their views about sterilisation. Results  Attitudes were less positive about parenting than about other aspects of sexuality, and less sexual freedom was seen as desirable for adults with ID. A surprising number of doctors agreed that sterilisation was a desirable practice. Study Two provided data about the conditions under which sterilisation was endorsed. Most doctors reported they had not been approached to perform sterilisations. Only 12% believed medical practitioners receive sufficient training in the area of disability and sexuality. Conclusions  The findings have implications for training and professional development for doctors.

Do we need to prescribe exercise differently for premenopausal and postmenopausal women?

The article by Kretzschmar et al 1 in this issue of Menopause details a study investigating the effect of a mild-intensity aerobic exercise training program on markers of mortality risk in both pre- and post-menopausal African American women. The findings of this study showed that aerobic exercise training was successful in improving some markers of cardiovascular disease (CVD) and mortality in post-menopausal women. The premise of this study, however, does suggest that increased exercise intensity may be required in post-menopausal women as opposed to pre-menopausal women to achieve the same decreased changes in CVD markers. The outcome of the study is thus of interest to the readers of Menopause and to all those who provide health care to postmenopausal women, as it suggests that higher levels of exercise intensity or perhaps additional interventions may need to be considered in this population to further decrease mortality risk. The study therefore, has greater implications than simply the suggestion of tailoring exercise interventions generally; rather, the publication highlights the importance of prescribing exercise as medicine in a tailored fashion for women depending on their menopausal status.

Climate change and financial regulation : challenges for the financial sector post the Global Financial Crisis

Regulation has played a significant role in shaping the financial services sector in Australia over the past few decades. Regulatory changes have included the establishment of the Australian Prudential Regulation Authority (APRA), floating the Australian dollar, allowing foreign financial institutions to operate domestically, the introduction of the superannuation guarantee charge, and the removal of interest rate controls. As the economy emerges from the worst financial crisis since the great depression, a new force of change that is recognised as one of the most significant sources of risk and opportunity facing the business community in the foreseeable future is that of climate change. Climate change is expected to be a significant change agent in the financial services sector as extreme weather patterns, sea level rises, and atmospheric changes impact on asset values (both investment and lending), project finance, and risk products. The financial services industry will be particularly affected by these developments, both as a provider of financial products (capital, credit, investment, advice, and insurance), and also through its powerful influence on the economy in terms of capital allocation. In addition, industry constituents will be heavily impacted by government regulation in this area (reporting, emissions trading and environmental policies), with respect to their own business practices and also those of their clients. This study reports the results of interviews conducted with senior members of the finance sector working in the sustainability area to gauge their perceptions of the challenges facing the sector with respect to climate change. Our results confirm that that regulatory intervention will be critical to climate change response gaining traction and momentum. In particular, regulatory certainty will promote engagement, particularly in relation to the Carbon Pollution Reduction Scheme (CPRS), with other developments needed in terms of information disclosure, performance and remuneration, and incentive programs. Accordingly, the significant potential risks and opportunities that climate change presents to the sector, and the broader economy, will in part be managed/realised only if a swift and significant regulatory response is achieved.

Internal audit involvement in enterprise risk management

Purpose The paper examines the impact of internal auditors’ involvement in Enterprise Risk Management (ERM) on perceptions of their willingness to report a breakdown in risk procedures and whether a strong relationship with the audit committee affects such willingness to report. The study also investigates the use of ERM and the role of internal audit in ERM in Australian private and public sector entities. Design/methodology/approach The study uses an experimental design, manipulating (i) the internal auditor’s involvement in ERM and (ii) the strength of the relationship between internal audit and the audit committee. Participants are 117 certified internal auditors. The study also gathers descriptive data on the use of ERM. Findings The study indicates that a high involvement in ERM impacts the perceptions of internal auditors’ willingness to report a breakdown in risk procedures to the audit committee. However, a strong relationship with the audit committee does not appear to affect their perceived willingness to report. The study also finds that the majority of organisations have recently adopted ERM. Internal auditors are involved in ERM assurance activities but some also engage in activities that could compromise objectivity.

Can physical activity prevent physical and cognitive decline in postmenopausal women? A systematic review of the literature

Background Participation in regular physical activity is among the most promising and cost effective strategies to reduce physical and cognitive decline and premature death. However, confusion remains about the amount, frequency, and duration of physical activity that is likely to provide maximum benefit as well as the way in which interventions should be delivered. Aims This paper aimed to review research on the impact of leisure-time and general physical activity levels on physical and cognitive decline in postmenopausal women. In a systematic review of the literature, empirical literature from 2009-2013 is reviewed to explore the potential impact of either commencing or sustaining physical activity on older women’s health. Results All studies found that physical activity was associated with lower rates of cognitive and physical decline and a significant reduction in all-cause mortality. In this review we found that exercise interventions (or lifestyle activities) that improved cardiorespiratory exercise capacity showed the most positive impact on physical health. Conclusions Findings suggest that programs should facilitate and support women to participate in regular exercise by embedding physical activity programs in public health initiatives, by developing home-based exercise programs that require few resources and by creating interventions that can incorporate physical activity within a healthy lifestyle. The review also suggests that clinicians should consider prescribing exercise in a tailored manner for older women to ensure that it is of a high enough intensity to obtain the positive sustained effects of exercise.

Should we tailor standardize exercise interventions to suit differing menopausal status?

The article by Kretzschmar et al in this issue of Menopause details a study investigating the effect of a mild-intensity aerobic exercise training program on markers of mortality risk in both pre- and post-menopausal African American women. The findings of this study showed that aerobic exercise training was successful in improving some markers of cardiovascular disease and mortality in post-menopausal women. The premise of this study, however, does suggest that increased exercise intensity may be required in post-menopausal women as opposed to pre menopausal women to achieve the same decreased changes in CVD markers. The outcome of the study is thus of interest to the readers of Menopause and to all those who provide health care to postmenopausal women, as they suggest that higher levels of exercise intensity or perhaps additional interventions may need to be considered in this population to further decrease mortality risk. The study therefore, has greater implications than simply the suggesting of tailoring exercise interventions generally, rather, the publication highlights the importance of prescribing exercise as medicine in a tailored fashion for women depending on their menopausal status.

Human single-stranded DNA binding protein 1 (hSSB1/NABP2) is required for the stability and repair of stalled replication forks

Aberrant DNA replication is a primary cause of mutations that are associated with pathological disorders including cancer. During DNA metabolism, the primary causes of replication fork stalling include secondary DNA structures, highly transcribed regions and damaged DNA. The restart of stalled replication forks is critical for the timely progression of the cell cycle and ultimately for the maintenance of genomic stability. Our previous work has implicated the single-stranded DNA binding protein, hSSB1/NABP2, in the repair of DNA double-strand breaks via homologous recombination. Here, we demonstrate that hSSB1 relocates to hydroxyurea (HU)-damaged replication forks where it is required for ATR and Chk1 activation and recruitment of Mre11 and Rad51. Consequently, hSSB1-depleted cells fail to repair and restart stalled replication forks. hSSB1 deficiency causes accumulation of DNA strand breaks and results in chromosome aberrations observed in mitosis, ultimately resulting in hSSB1 being required for survival to HU and camptothecin. Overall, our findings demonstrate the importance of hSSB1 in maintaining and repairing DNA replication forks and for overall genomic stability.

Head and neck squamous-cell cancer and its association with polymorphic enzymes of xenobiotic metabolism and repair

Tobacco smoking, alcohol drinking, and occupational exposures to polycyclic aromatic hydrocarbons are the major proven risk factors for human head and neck squamous-cell cancer (HNSCC). Major research focus on gene-environment interactions concerning HNSCC has been on genes encoding enzymes of metabolism for tobacco smoke constituents and repair enzymes. To investigate the role of genetically determined individual predispositions in enzymes of xenobiotic metabolism and in repair enzymes under the exogenous risk factor tobacco smoke in the carcinogenesis of HNSCC, we conducted a case-control study on 312 cases and 300 noncancer controls. We focused on the impact of 22 sequence variations in CYP1A1, CYP1B1, CYP2E1, ERCC2/XPD, GSTM1, GSTP1, GSTT1, NAT2, NQO1, and XRCC1. To assess relevant main and interactive effects of polymorphic genes on the susceptibility to HNSCC we used statistical models such as logic regression and a Bayesian version of logic regression. In subgroup analysis of nonsmokers, main effects in ERCC2 (Lys751Gln) C/C genotype and combined ERCC2 (Arg156Arg) C/A and A/A genotypes were predominant. When stratifying for smokers, the data revealed main effects on combined CYP1B1 (Leu432Val) C/G and G/G genotypes, followed by CYP1B1 (Leu432Val) G/G genotype and CYP2E1 (-70G>T) G/T genotype. When fitting logistic regression models including relevant main effects and interactions in smokers, we found relevant associations of CYP1B1 (Leu432Val) C/G genotype and CYP2E1 (-70G>T) G/T genotype (OR, 10.84; 95% CI, 1.64-71.53) as well as CYP1B1 (Leu432Val) G/G genotype and GSTM1 null/null genotype (OR, 11.79; 95% CI, 2.18-63.77) with HNSCC. The findings underline the relevance of genotypes of polymorphic CYP1B1 combined with exposures to tobacco smoke.

Logic-gate devices based on printed polymer semiconducting nanostripes

The applications of organic semiconductors in complex circuitry such as printed CMOS-like logic circuits demand miniaturization of the active structures to the submicrometric and nanoscale level while enhancing or at least preserving the charge transport properties upon processing. Here, we addressed this issue by using a wet lithographic technique, which exploits and enhances the molecular order in polymers by spatial confinement, to fabricate ambipolar organic field effect transistors and inverter circuits based on nanostructured single component ambipolar polymeric semiconductor. In our devices, the current flows through a precisely defined array of nanostripes made of a highly ordered diketopyrrolopyrrole-benzothiadiazole copolymer with high charge carrier mobility (1.45 cm2 V-1 s-1 for electrons and 0.70 cm2 V-1 s-1 for holes). Finally, we demonstrated the functionality of the ambipolar nanostripe transistors by assembling them into an inverter circuit that exhibits a gain (105) comparable to inverters based on single crystal semiconductors.

A population-specific HTR2B stop codon predisposes to severe impulsivity

Impulsivity, describing action without foresight, is an important feature of several psychiatric diseases, suicidality and violent behaviour. The complex origins of impulsivity hinder identification of the genes influencing it and the diseases with which it is associated. Here we perform exon-focused sequencing of impulsive individuals in a founder population, targeting fourteen genes belonging to the serotonin and dopamine domain. A stop codon in HTR2B was identified that is common (minor allele frequency > 1%) but exclusive to Finnish people. Expression of the gene in the human brain was assessed, as well as the molecular functionality of the stop codon, which was associated with psychiatric diseases marked by impulsivity in both population and family-based analyses. Knockout of Htr2b increased impulsive behaviours in mice, indicative of predictive validity. Our study shows the potential for identifying and tracing effects of rare alleles in complex behavioural phenotypes using founder populations, and indicates a role for HTR2B in impulsivity.

Molecular phylogeny, biogeography, and habitat preference evolution of marsupials

Marsupials exhibit great diversity in ecology and morphology. However, compared to their sister group, the placental mammals, our understanding of many aspects of marsupial evolution remains limited. We use 101 mitochondrial genomes and data from 26 nuclear loci to reconstruct a dated phylogeny including 97% of extant genera and 58% of modern marsupial species. This tree allows us to analyze the evolution of habitat preference and geographic distributions of marsupial species through time. We found a pattern of mesic-adapted lineages evolving to use more arid and open habitats, which is broadly consistent with regional climate and environmental change. However, contrary to the general trend, several lineages subsequently appear to have reverted from drier to more mesic habitats. Biogeographic reconstructions suggest that current views on the connectivity between Australia and New Guinea/Wallacea during the Miocene and Pliocene need to be revised. The antiquity of several endemic New Guinean clades strongly suggests a substantially older period of connection stretching back to the Middle Miocene, and implies that New Guinea was colonized by multiple clades almost immediately after its principal formation.