Editorial

No Abstrac

Editorial: Launching our new website

No Abstrac

Cerebral blood flow and behavioural effects of caffeine in habitual and non-habitual consumers of caffeine: A near infrared spectroscopy study

Caffeine has been shown to modulate cerebral blood flow, with little evidence of tolerance to these effects following habitual use. However, previous studies have focused on caffeine levels much higher than those found in dietary servings and have compared high caffeine consumers with low consumers rather than 'non-consumers'. The current placebo-controlled double-blind, balanced-crossover study employed near infrared spectroscopy to monitor pre-frontal cerebral-haemodynamics at rest and during completion of tasks that activate the pre-frontal cortex. Twenty healthy young habitual and non-habitual consumers of caffeine received 75mg caffeine or placebo. Caffeine significantly decreased cerebral blood flow but this was subject to a significant interaction with consumption status, with no significant effect being shown in habitual consumers and an exaggerated effect in non-habitual consumers. These findings suggest that caffeine, at levels typically found in a single dietary serving, is able to modulate cerebral blood flow but these effects are subject to tolerance

Empirically derived guidance for social scientists to influence environmental policy

Failure to stem trends of ecological disruption and associated loss of ecosystem services worldwide is partly due to the inadequate integration of the human dimension into environmental decision-making. Decision-makers need knowledge of the human dimension of resource systems and of the social consequences of decision-making if environmental management is to be effective and adaptive. Social scientists have a central role to play, but little guidance exists to help them influence decision-making processes. We distil 348 years of cumulative experience shared by 31 environmental experts across three continents into advice for social scientists seeking to increase their influence in the environmental policy arena. Results focus on the importance of process, engagement, empathy and acumen and reveal the importance of understanding and actively participating in policy processes through co-producing knowledge and building trust. The insights gained during this research might empower a science-driven cultural change in science-policy relations for the routine integration of the human dimension in environmental decision making; ultimately for an improved outlook for earth’s ecosystems and the billions of people that depend on them

Diagnosis and staging of laryngopharyngeal tumours with flexible endoscopy: A prospective study

Background: Many suspected laryngopharyngeal neoplasms are examination under general anaesthesia (EUA). Office-based endoscopy is already routinely performed on all patients presenting with a suspected laryngopharyngeal neoplasm. Accurate clinical staging and tissue sampling using flexible endoscopy may eliminate the need for EUA. Aim: To compare the use of flexible endoscopy to EUA as primary diagnostic tool of laryngopharyngeal lesions to EUA, using accuracy of tissue samples obtained and clinical staging as primary outcome measures. Duration, patient tolerance and cost implications were also assessed. Setting: The study was performed in the outpatient department and surgical theatres of Tygerberg Hospital, Cape Town, South Africa. Methods: A prospective study compared staging and tissue sampling accuracy with flexible endoscopy to EUA in 54 patients. Duration, tolerance and cost implications were also assessed. Results: Flexible endoscopic biopsy had a 77.1% sensitivity, 100% specificity and 82.2% diagnostic accuracy. Liquid-based cytology had 97.3% sensitivity, 100% specificity and 97.9% diagnostic accuracy in differentiating high-grade lesions from low-grade lesions. Local staging agreement occurred in 88.6% (n = 31/35) of malignant cases. The mean duration was 15 ± 7 min; 86% of patients perceived the procedure as tolerable. Flexible endoscopy as a primary diagnostic tool would have avoided EUA in 68.6% (n = 24/35) of squamous cell carcinoma cases, with a R128 232 cost savings. Conclusion: Office-based endoscopy is an accurate, well-tolerated, time- and cost-effective primary diagnostic tool of laryngopharyngeal lesions. It reduces the number of patients requiring EUA. Further evaluation is empirical when the histopathology does not confirm the clinical suspicion of malignancy

Inhibition of Dihydrotestosterone Synthesis in Prostate Cancer by Combined Frontdoor and Backdoor Pathway Blockade

Androgen deprivation therapy (ADT) is palliative and prostate cancer (CaP) recurs as lethal castration-recurrent/resistant CaP (CRPC). One mechanism that provides CaP resistance to ADT is primary backdoor androgen metabolism, which uses up to four 3α-oxidoreductases to convert 5α-androstane-3α,17β-diol (DIOL) to dihydrotestosterone (DHT). The goal was to determine whether inhibition of 3α-oxidoreductase activity decreased conversion of DIOL to DHT. Protein sequence analysis showed that the four 3α-oxidoreductases have identical catalytic amino acid residues. Mass spectrometry data showed combined treatment using catalytically inactive 3α-oxidoreductase mutants and the 5α-reductase inhibitor, dutasteride, decreased DHT levels in CaP cells better than dutasteride alone. Combined blockade of frontdoor and backdoor pathways of DHT synthesis provides a therapeutic strategy to inhibit CRPC development and growth

The fallacy of the bolted horse: changing our thinking about mature-age Aboriginal and Torres Strait Islander university students

The aim of this paper is to critically review and analyse the public representations of mature-age university students in developed and some developing nations and how they compare to the public representations of mature-age Aboriginal and Torres Strait Islander university students in Australia (‘students’ also refers to graduates unless the context requires specificity). Relevant texts were identified by reviewing education-related academic and policy literature, media opinion and reportage pieces, conference proceedings, and private sector and higher education reviews, reports and submissions. What this review reveals is striking: very few commentators are publicly and unambiguously encouraging, supporting and celebrating mature-age Aboriginal and Torres Strait Islander university students. This strongly contrasts with the discussions around mature-age university students in general, where continuous or lifelong learning is acclaimed and endorsed, particularly as our populations grow older and remain healthier and there are relatively lower numbers of working-age people. While scholars, social commentators, bureaucrats and politicians enthusiastically highlight the intrinsic and extrinsic value of the mature-age student’s social and economic contributions, the overarching narrative of the mature-age Aboriginal and Torres Strait Islander student is one of ‘the horse has bolted’, meaning that it is too late for this cohort and therefore society to benefit from their university education. In this paper we examine these conflicting positions, investigate why this dichotomy exists, present an alternative view for consideration and make recommendations for further research into this area

Visualising biological data: a semantic approach to tool and database integration

<p>Abstract</p> <p>Motivation</p> <p>In the biological sciences, the need to analyse vast amounts of information has become commonplace. Such large-scale analyses often involve drawing together data from a variety of different databases, held remotely on the internet or locally on in-house servers. Supporting these tasks are <it>ad hoc </it>collections of data-manipulation tools, scripting languages and visualisation software, which are often combined in arcane ways to create cumbersome systems that have been customised for a particular purpose, and are consequently not readily adaptable to other uses. For many day-to-day bioinformatics tasks, the sizes of current databases, and the scale of the analyses necessary, now demand increasing levels of automation; nevertheless, the unique experience and intuition of human researchers is still required to interpret the end results in any meaningful biological way. Putting humans in the loop requires tools to support real-time interaction with these vast and complex data-sets. Numerous tools do exist for this purpose, but many do not have optimal interfaces, most are effectively isolated from other tools and databases owing to incompatible data formats, and many have limited real-time performance when applied to realistically large data-sets: much of the user's cognitive capacity is therefore focused on controlling the software and manipulating esoteric file formats rather than on performing the research.</p> <p>Methods</p> <p>To confront these issues, harnessing expertise in human-computer interaction (HCI), high-performance rendering and distributed systems, and guided by bioinformaticians and end-user biologists, we are building reusable software components that, together, create a toolkit that is both architecturally sound from a computing point of view, and addresses both user and developer requirements. Key to the system's usability is its direct exploitation of semantics, which, crucially, gives individual components knowledge of their own functionality and allows them to interoperate seamlessly, removing many of the existing barriers and bottlenecks from standard bioinformatics tasks.</p> <p>Results</p> <p>The toolkit, named Utopia, is freely available from <url>http://utopia.cs.man.ac.uk/</url>.</p

Manufacturing of agarose-based chromatographic adsorbents – effect of ionic strength and cooling conditions on particle structure and mechanical strength

The effect of ionic strength of agarose solution and quenching temperature of the emulsion on the structure and mechanical strength of agarose-based chromatographic adsorbents was investigated. Solutions of agarose containing different amounts of NaCl were emulsified at elevated temperature in mineral oil using a high-shear mixer. The hot emulsion was quenched at different temperatures leading to the gelation of agarose and formation of soft particles. Analysis of Atomic Force Microscopy (AFM) images of particle surfaces shows that pore size of particles increases with ionic strength and/or high quenching temperature. Additionally it has been found that the compressive strength of particles measured by micromanipulation also increases with ionic strength of the emulsion and/or high quenching temperature but these two parameters have no significant effect on the resulting particle size and particle size distribution. Results from both characterization methods were compared with Sepharose 4B, a commercial agarose-based adsorbent. This is the first report examining the effect of ionic strength and cooling conditions on the microstructure of micron-sized agarose beads for bioseparation