Anti-staphylococcal activity of C-methyl flavanones from propolis of Australian stingless bees (Tetragonula carbonaria) and fruit resins of Corymbia torelliana (Myrtaceae)

Propolis of Australian stingless bees (Tetragonula carbonaria, Meliponini) originating from Corymbia torelliana (Myrtaceae) fruit resins was tested for its antimicrobial activities as well as its flavonoid contents. This study aimed at the isolation, structural elucidation and antibacterial testing of flavanones of C. torelliana fruit resins that are incorporated into stingless bee propolis. Flavanones of this study were elucidated by spectroscopic and spectrometric methods including UV, 1D and 2D NMR, EI-MS, ESI-MS and HR-MS. The results indicated known C-methylated flavanones namely, 1 (2S)-cryptostrobin, its regioisomer 2 (2S)- stroboponin, 3 (2S)- cryptostrobin 7-methyl ether, and 6 (2S)- desmethoxymatteucinol, and known flavanones 4 (2S)- pinostrobin and 5 (2S)- pinocembrin as markers for C. torelliana fruit resins and one propolis type. Ethanolic preparations of propolis were shown to be active against Staphylococcus aureus (ATCC 25923) and to a lesser extent against Pseudomonas aeruginosa (ATCC 27853). C. torelliana flavanones inhibited the growth of S. aureus therefore contributing to the antibacterial effects observed for Australian stingless bee propolis extracts.

Atmospheric pressure gas plasma-induced colorectal cancer cell death is mediated by Nox2-ASK1 apoptosis pathways and oxidative stress is mitigated by Srx-Nrf2 anti-oxidant system

Atmospheric pressure gas plasma (AGP) generates reactive oxygen species (ROS) that induce apoptosis in cultured cancer cells. The majority of cancer cells develop a ROS-scavenging anti-oxidant system regulated by Nrf2, which confers resistance to ROS-mediated cancer cell death. Generation of ROS is involved in the AGP-induced cancer cell death of several colorectal cancer cells (Caco2, HCT116 and SW480) by activation of ASK1-mediated apoptosis signaling pathway without affecting control cells (human colonic sub-epithelial myofibroblasts; CO18, human fetal lung fibroblast; MRC5 and fetal human colon; FHC). However, the identity of an oxidase participating in AGP-induced cancer cell death is unknown. Here, we report that AGP up-regulates the expression of Nox2 (NADPH oxidase) to produce ROS. RNA interference designed to target Nox2 effectively inhibits the AGP-induced ROS production and cancer cell death. In some cases both colorectal cancer HT29 and control cells showed resistance to AGP treatment. Compared to AGP-sensitive Caco2 cells, HT29 cells show a higher basal level of the anti-oxidant system transcriptional regulator Nrf2 and its target protein sulfiredoxin (Srx) which are involved in cellular redox homeostasis. Silencing of both Nrf2 and Srx sensitized HT29 cells, leads to ROS overproduction and decreased cell viability. This indicates that in HT29 cells, Nrf2/Srx axis is a protective factor against AGP-induced oxidative stress. The inhibition of Nrf2/Srx signaling should be considered as a central target in drug-resistant colorectal cancer treatments.

Polysaccharopeptide enhanced the anti-cancer effect of gamma-tocotrienol through activation of AMPK

Background Prostate cancer (PCa) frequently relapses after hormone ablation therapy. Unfortunately, once progressed to the castration resistant stage, the disease is regarded as incurable as prostate cancer cells are highly resistant to conventional chemotherapy. Method We recently reported that the two natural compounds polysaccharopeptide (PSP) and Gamma-tocotrienols (γ-T3) possessed potent anti-cancer activities through targeting of CSCs. In the present study, using both prostate cancer cell line and xenograft models, we seek to investigate the therapeutic potential of combining γ-T3 and PSP in the treatment of prostate cancer. Result We showed that in the presence of PSP, γ-T3 treatment induce a drastic activation of AMP-activated protein kinase (AMPK). This was accompanied with inactivation of acetyl-CoA carboxylase (ACC), as evidenced by the increased phosphorylation levels at Ser 79. In addition, PSP treatment also sensitized cancer cells toward γ-T3-induced cytotoxicity. Furthermore, we demonstrated for the first time that combination of PSP and γ-T3 treaments significantly reduced the growth of prostate tumor in vivo. Conclusion Our results indicate that PSP and γ-T3 treaments may have synergistic anti-cancer effect in vitro and in vivo, which warrants further investigation as a potential combination therapy for the treatment of cancer.

William James, Sciences of Mind, and Anti-imperial Discourse

In the past few decades, the humanities and social sciences have developed new methods of reorienting their conceptual frameworks in a “world without frontiers.” In this book, Bernadette M. Baker offers an innovative approach to rethinking sciences of mind as they formed at the turn of the twentieth century, via the concerns that have emerged at the turn of the twenty-first. The less-visited texts of Harvard philosopher and psychologist William James provide a window into contemporary debates over principles of toleration, anti-imperial discourse, and the nature of ethics. Baker revisits Jamesian approaches to the formation of scientific objects including the child mind, exceptional mental states, and the ghost to explore the possibilities and limits of social scientific thought dedicated to mind development and discipline formation around the construct of the West.

Evaluation of transgenic bananas expressing anti-apoptotic genes for resistance against Fusarium wilt

The banana industry worldwide is under threat from a fungal disease known as Fusarium wilt, a disease for which there is no chemical control. Conventional breeding approaches to generate resistant banana varieties are lengthy and very difficult. As such, genetic engineering for disease resistance is considered the most viable control option. In this PhD thesis, genetically modified banana plants were generated using several different stress tolerance genes. When challenged with Fusarium wilt in glasshouse trials, some lines showed increased resistance to the disease. The promising elite lines generated in this study will now require testing in field trials.

Anti-bacterial surfaces: Natural agents, mechanisms of action, and plasma surface modification

Strategies that confine antibacterial and/or antifouling property to the surface of the implant, by modifying the surface chemistry and morphology or by encapsulating the material in an antibiotic-loaded coating, are most promising as they do not alter bulk integrity of the material. Among them, plasma-assisted modification and catechol chemistry stand out for their ability to modify a wide range of substrates. By controlling processing parameters, plasma environment can be used for surface nano structuring, chemical activation, and deposition of biologically active and passive coatings. Catechol chemistry can be used for material-independent, highly-controlled surface immobilisation of active molecules and fabrication of biodegradable drug-loaded hydrogel coatings. In this article, we comprehensively review the role plasma-assisted processing and catechol chemistry can play in combating bacterial colonisation on medically relevant coatings, and how these strategies can be coupled with the use of natural antimicrobial agents to produce synthetic antibiotic-free antibacterial surfaces.

Human trafficking heroes and villains: Representing the problem in anti-trafficking awareness campaigns

Since the declaration by the United Nations that awareness raising should be a key part of efforts to combat human trafficking, government and non-government organisations have produced numerous public awareness campaigns designed to capture the public’s attention and sympathy. These campaigns represent the ‘problem’ of trafficking in specific ways, creating heroes and villains by placing the blame for trafficking on some, while obscuring the responsibility of others. This paper adopts Carol Bacchi’s ‘What is the problem represented to be?’ framework for examining the politicisation of problem representation in 18 anti-trafficking awareness campaigns. It is argued that these campaigns construct a narrow understanding of the problem through the depiction of ‘ideal offenders’. In particular, a strong focus on the demand for commercial sex as causative of human trafficking serves to obscure the problematic role of consumerism in a wide range of industries, and perpetuates an understanding of trafficking that fails to draw a necessary distinction between the demand for labour, and the demand for ‘exploitable’ labour. This problem representation also obscures the role governments in destination countries may play in causing trafficking through imposing restrictive migration regimes that render migrants vulnerable to traffickers.

Realities on the ground: Human trafficking constructs in Thailand and the implications on NGO anti-trafficking prevention strategies

This thesis is a qualitative study that examines how participating staff from Thai based non-governmental organisations interpret and construct the notion of human trafficking; and how this impacts prevention methods. The research examined the impact of different socio-cultural, political and religious ideologies on anti-trafficking prevention and programme implementation. Findings highlighted that while a 'raid and rescue' approach to human trafficking was widely recognised by donors and the media; it was not suitable or complementary to sustainable and community focused anti-trafficking models. Rather, a holistic approach that considers contextual factors and inter-agency collaboration is essential for effective anti-trafficking prevention strategies.

Anti-bribery disclosures: A response to networked governance

This study examined the posited link between networked governance (the activities of NGOs and the media) and the anti-bribery disclosures of two global telecommunication companies. Based on a joint consideration of legitimacy theory, media agenda setting theory and responsive regulation, the findings show that anti-bribery disclosures are positively associated with the activities of the media and NGO initiatives. The findings also show that companies make anti-bribery disclosures to maintain symbolic legitimacy but are less prominent in effecting a substantive change in their accountability practices.

Fly-eye inspired superhydrophobic anti-fogging inorganic nanostructures

Fly-eye bio-inspired inorganic nanostructures are synthesized via a two-step self-assembly approach, which have low contact angle hysteresis and excellent anti-fogging properties, and are promising candidates for anti-freezing/fogging materials to be applied in extreme and hazardous environments.

Looking at the other side: Families, public health and anti-vaccination

The choice to vaccinate or not to vaccinate a child is usually an ‘informed decision’, however, it is how this decision is informed which is of most importance. More frequently, families are turning to the Internet, in particular social media, as a data source to support their decisions. However, much of the online information may be unscientific or biased. While issues such as vaccination will always see dissenting voices, engaging with that ‘other side’ is difficult in the public policy debate which is informed by evidence based science. This chapter investigates the other side in light of the growing adoption and reliance on social media as a source of anti-vaccine information. The study adopts a qualitative approach to data collection and is based on a critical discourse analysis of online social media discourse. The findings demonstrate the valuable contribution this approach can make to public policy work in vaccination.

Polysaccharopeptide enhanced the anti-cancer effect of gammatocotrienol through activation of AMPK

Prostate cancer (PCa) frequently relapses after hormone ablation therapy. Unfortunately, once progressed to the castration resistant stage, the disease is regarded as incurable as prostate tumours are highly resistant to conventional chemotherapy. Therefore, an effective treatment strategy is urgently needed for improving the treatment outcome of the patients.

NFPOs and their anti-corruption disclosure practices: Evidence from Australia

By focusing on major Australian overseas aid not-for-profit organisations (NFPOs), this study has found that NFPOs’ public disclosures lack appropriate commentary relating to anti-corruption measures. We found that this could be due to a break down in regulatory oversight caused by a lack of mandatory reporting standards. This finding reinforces the experience of NFPOs in terms of addressing anti-corruption issues. The key lesson is that there is a need for significant improvement in the anti-corruption regulations, hence associated disclosure practices within the NFPOs sector.