Fabrication of a microfluidic platform for impedance analysis of cultured endothelial cell monolayers.

Assessing the functionality of the endothelium can provide insight into the initiation and formation of arterial diseases. One of the most important functions of the endothelial layer is its permeability. The integrity of the cell monolayer and its ability to transport molecules can be assessed in vitro by investigating the electrical impedance. In this study, a microfluidic platform was created using an electrode-patterned glass substrate and microfluidic poly(dimethyl siloxane) (PDMS) substrate. The electrode glass base of the structure was fabricated with platinum square electrodes of various sizes ranging from 10x10 ìm2 to 160x160 ìm2 and a larger, common counter electrode. Master microfluidic molds for PDMS casting were created by micro-milling Lexan® and photolithographically patterning SU-8. The microfluidic PDMS substrates reversibly and conformally bonded to the glass-electrode substrate. The microfluidic platforms were characterized by loading the microchannels with cell growth media alone, cell growth media and fibronectin, and cell growth media, fibronectin and human umbilical vein endothelial cells and obtaining impedance spectra. The experiments were performed under both no flow and flow conditions. Fibronectin did not significantly alter the collected impedance spectrum compared to media alone under no flow conditions. Under no flow conditions, impedance spectra measurements were able to detect the presence of cultured cells on the electrodes. The presence of fibronectin and various tested flow rates did not alter the impedance spectrum compared to media alone under static conditions. After further investigations, the microfluidic platform will become a versatile means of characterizing endothelial cell layer behavior

Purinergic receptor mediated calcium signalling in urothelial cells

Non-neuronal ATP released from the urothelium in response to bladder stretch is a key modulator of bladder mechanosensation. Whilst non-neuronal ATP acts on the underlying bladder afferent nerves to facilitate sensation, there is also the potential for ATP to act in an autocrine manner, modulating urothelial cell function. The aim of this study was to systematically characterise the functional response of primary mouse urothelial cells (PMUCs) to ATP. PMUCs isolated from male mice (14-16 weeks) were used for live-cell fluorescent calcium imaging and qRT-PCR to determine the expression profile of P2X and P2Y receptors. The majority of PMUCs (74-92%) responded to ATP (1 μM-1 mM), as indicted by an increase in intracellular calcium (iCa2+). PMUCs exhibited dose-dependent responses to ATP (10 nM-1 mM) in both calcium containing (2 mM, EC50 = 3.49 ± 0.77 μM) or calcium free (0 mM, EC50 = 9.5 ± 1.5 μM) buffers. However, maximum iCa2+ responses to ATP were significantly attenuated upon repetitive applications in calcium containing but not in calcium free buffer. qRT-PCR revealed expression of P2X1-6, and P2Y1-2, P2Y4, P2Y6, P2Y11-14, but not P2X7 in PMUCs. These findings suggest the major component of ATP induced increases in iCa2+ are mediated via the liberation of calcium from intracellular stores, implicating functional P2Y receptors that are ubiquitously expressed on PMUCs.Russell Chess-Williams, Donna J. Sellers, Stuart M. Brierley, David Grundy, Luke Grund

Attitudes of Paramedic Students towards Specific Medical Conditions: A Four-Year Study

Purpose: The purpose of this study was to determine the attitude of first year students entering a paramedic course over 4 consecutive yearly intakes toward patients with intellectual disability, substance abuse, attempted suicide, and acute mental illness. Method: The students’ attitude towards four medical conditions commonly encountered in the out-of-hospital setting was assessed using the Medical Condition Regard Scale (MCRS). The MCRS score ranges from 11 to 66. Results: 230 students in Victoria, Australia, participated in the study; 66% were female, and 76% of all students \u3c 21 years of age. Students showed the most negative attitudes towards substance abuse, mean 35(SD+6.6), and the most positive attitude toward intellectual disability, mean 38.2(SD+6.3). Students in 2008 cohort displayed significantly higher regard for all medical conditions (pConclusions: The study findings suggest that these students in Victoria, Australia, entering an undergraduate paramedic or paramedic/nursing course have a relatively poor attitude towards the four reviewed medical conditions, particularly substance abuse

Industrial biotechnology for developing countries: The case for genetically modified biofuels in Kenya

Attempts to diversify the energy portfolios of developed countries with green technologies have brought competition between food and fuel for crop production resources to the forefront of public policy debates. Biofuel policies in the European Union (EU) and the United States (US) mandate the long-term use of renewable energy in transportation, independent of production capacity and technical feasibility. Both the US and EU policies explicitly allow for biofuel imports and, hence, have the potential to provide developing countries with export opportunities. For example, the EU is seen as a market that could be supplied with biofuels produced in Kenya. As a result, contentious land acquisitions have been made in Kenya to make way for sugar cane and jatropha cultivation for biofuel production. One potential means of improving the efficiency of Kenya’s agricultural sector is the application of transgenic technologies. The objective of this article is to assess whether a biofuel industry could be developed in Kenya, based on the use of genetically modified (GM) feedstocks to supply the EU demand for biofuel. This article concludes that GM agriculture will improve the economic returns for those Kenyan farmers willing to engage in the production of GM biofuel crops.Keywords: Barriers to trade, energy policy, genetically modified (GM) crops, international trade, land-use policyAfrican Journal of Biotechnology Vol. 12(15), pp. 1722-173

There and back again: detecting regularity in human encounter communities

Detecting communities that recur over time is a challenging problem due to the potential sparsity of encounter events at an individual scale and inherent uncertainty in human behavior. Existing methods for community detection in mobile human encounter networks ignore the presence of temporal patterns that lead to periodic components in the network. Daily and weekly routine are prevalent in human behavior and can serve as rich context for applications that rely on person-to-person encounters, such as mobile routing protocols and intelligent digital personal assistants. In this article, we present the design, implementation, and evaluation of an approach to decentralized periodic community detection that is robust to uncertainty and computationally efficient. This alternative approach has a novel periodicity detection method inspired by a neural synchrony measure used in the field of neurophysiology. We evaluate our approach and investigate human periodic encounter patterns using empirical datasets of inferred and direct-sensed encounters

Spatial calibration of an optical see-through head-mounted display

We present here a method for calibrating an optical see-through Head Mounted Display (HMD) using techniques usually applied to camera calibration (photogrammetry). Using a camera placed inside the HMD to take pictures simultaneously of a tracked object and features in the HMD display, we could exploit established camera calibration techniques to recover both the intrinsic and extrinsic properties of the~HMD (width, height, focal length, optic centre and principal ray of the display). Our method gives low re-projection errors and, unlike existing methods, involves no time-consuming and error-prone human measurements, nor any prior estimates about the HMD geometry

Improved Efficacy of a Gene Optimised Adenovirus-based Vaccine for Venezuelan Equine Encephalitis Virus

<p>Abstract</p> <p>Background</p> <p>Optimisation of genes has been shown to be beneficial for expression of proteins in a range of applications. Optimisation has increased protein expression levels through improved codon usage of the genes and an increase in levels of messenger RNA. We have applied this to an adenovirus (ad)-based vaccine encoding structural proteins (E3-E2-6K) of Venezuelan equine encephalitis virus (VEEV).</p> <p>Results</p> <p>Following administration of this vaccine to Balb/c mice, an approximately ten-fold increase in antibody response was elicited and increased protective efficacy compared to an ad-based vaccine containing non-optimised genes was observed after challenge.</p> <p>Conclusion</p> <p>This study, in which the utility of optimising genes encoding the structural proteins of VEEV is demonstrated for the first time, informs us that including optimised genes in gene-based vaccines for VEEV is essential to obtain maximum immunogenicity and protective efficacy.</p