1 | Alvin Teo | University of Warwick
My project focuses on the aspect of bacterial cell wall biosynthesis and its inherent connection to cell division. Before a bacterial cell is ready to divide, new cell wall materials have to be formed. This is a complex but well-coordinated process, with a plethora of proteins interacting in a coorperative and transient manner. The emphasis of the project is being placed on the membrane-associated stage for the biosynthesis of peptidoglycan, which is the major structural component of the bacterial cell wall. It is a polymer mesh consisting of alternating units of N-acetylmuramic acid and N-acetylglucosamine, being cross-linked via stem peptide bridges. My project will address the challenges in terms of overexpressing the integral membrane proteins involved, and also their subsequent extraction and solubilisation in active form. Traditional approaches using detergent solubilisation of membrane proteins are often denaturing due to the sequestration of membrane lipids stabilising the proteins. Furthermore, the membrane proteins solubilised in detergent micelles are not presented in their native lipidic environment for subsequent biophysical and biochemical analysis. My project will exploit a novel non-detergent technique to encapsulate the integral membrane proteins together with their native lipidic components into “nanodiscs” stabilised by a copolymer of styrene maleic acid (SMA). A range of bioanalytical studies facilitated by the “nanodisc” system can provide the vital information on the structure and function of many of these membrane proteins to underpin the development of next generation antimicrobial drugs.
2 | Lim Ee Lyn | University of Cambridge
How do PI3K inhibitors affect the anti-tumour immune response? It has long been known that our immune systems are able to attack and eliminate cancer cells, and much research is focused on enhancing the anti-tumour immune response in cancer therapy. p110δ is the dominant catalytic subunit isoform of the PI3K enzyme family in white blood cells, and drugs inhibiting its function have been successfully trialled in the treatment of leukaemia. However, previous work in the Okkenhaug lab has shown that the inactivation of p110δ can also bolster resistance to solid tumours in mice. While p110δ inhibition appears to increase the potency of the anti-tumour immune response, we have also discovered that cytotoxic T lymphocytes, the subset of immune cells chiefly responsible for killing cancer cells, function less effectively without p110δ activity – therefore the effects of p110δ inhibition may be complex, differentially modulating the many elements of the immune response to give an overall benefit. This project aims to elucidate the mechanistic effects of p110δ inactivation, towards the development of a novel cancer therapy.
3 | Jia Wen Choo | University of Oxford
Synthetic biology is engineering-inspired – biological networks are distilled into modular and standardised components that can be reassembled into novel systems. In addition to high profile applications in energy production and medicine, synthetic biology also allows a more sophisticated approach to the traditional discipline of transferring genes into plants to understand gene function. Instead of creating gene constructs of only a few genes, complex constructs coding for entire gene systems are possible. This facilitates a more fine-tuned approach to understanding gene function. A rudimentary example system would be a fluorescent gene that can be activated when an inducer, such as light or a hormone, is added. Thus, a gene that may be lethal if always expressed can be induced at a suitable time and place, allowing us to understand the gene’s role in development. In this poster I describe the Golden Gate Modular Cloning toolkit, a new molecular cloning technology that brings us closer to achieving the aims of synthetic biology. By allowing the DNA cutting and pasting steps to proceed in the same reaction, this technology circumvents the laborious process of having to clone and verify genes one by one. The toolkit consists of standardised promoters, coding regions and terminators that can be assembled into “transcription units”, which can then be assembled into gene systems. The toolkit was used to create inducible systems coupled to the blue GUS gene that were later transformed into rice (Oryza sativa). The ultimate aim is to couple these inducible systems to candidate genes thought to be responsible for the evolution of the more efficient C4 mode of photosynthesis, and to engineer this metabolic system into C3 plants. In line with this goal, this project explores the toolkit’s utility in monocotyledonous plants and the optimisation issues involved.
4 | Suk May Low | University of Sheffield
Could code-switching be an answer to the language dilemma in multilingual science classrooms? In year 2003, the policy of teaching mathematics and science in English was implemented in Malaysia. However, this policy was abolished and starting from 2011, students are required to learn mathematics and science in Malay. During this “soft-landing” period, only Primary One students are required to learn these subjects in Malay. For those who have started with the previous policy, they can choose to continue learning in English or both English and Malay until they complete their secondary education. This means, Sixth Form students in 2022 will be the first cohort of students having learnt mathematics and science in Malay for 11 years before starting their pre-University course in English. It is foreseen that there will be problems for both teachers and students as they will experience a change of language of instruction in these subjects. Therefore, this study is proposed to investigate the effectiveness of classroom code-switching (CS) as a solution for such a situation. In this study, three schools will be chosen for participation and all science teachers of these schools will be interviewed. Classroom observations and audio recordings will be done in one particular science class from each school, totalling 24 hours of transcript to be analysed. Students in the observed class will also be completing a questionnaire to gauge their views on teacher’s CS. This presentation will present the results collected from the study which will be carried out in Summer 2013. It is hoped that through this study, awareness of classroom CS will be raised among the teachers and it will be encouraged as a new form of classroom communication in the field of applied linguistics. A formal training module on classroom CS will also be proposed and introduced to the education ministry as a recommendation from this study.
5 | Firdaus Samsudin | University of Oxford
Improving Drug Delivery: Computational Studies of Peptide Transporters. The human peptide transport system is a promising route for improving oral drug absorption. In addition to taking up di- and tripeptides along the gastrointestinal tract during protein digestion, the proton-coupled transporter PepT1 also shows affinity for a broad range of peptide-mimetic drugs like the β-lactam antibiotics. The promiscuity of this symporter has recently been exploited in the development of amino acid prodrugs of floxuridine used to treat colon carcinoma and dipeptide-drug conjugates of azidothymidine for AIDS therapy. However, in the absence of structural data, rational drug design targeting this membrane protein has been hitherto restricted to empirical approaches. The crystal structure of a bacterial homolog, PepTSt, provides a useful model system for the understanding of the key protein-ligand interactions and building an accurate pharmacophore model. In this study, we validate the use of in silico methods of varying speed and accuracy to predict the transport of peptides and drugs by PepTSt and PepT1 homology model. We found that a good correlation to experimental data can be achieved by fast end-point free energy calculations, although rigorous methods such as thermodynamic integration are essential to distinguish, to a high accuracy, between substrates of similar transport properties. Overall, our studies demonstrate the significant potential of computational predictions to design drugs with enhanced bioavailability.
6 | Fazlyn Reeny Abdul Razak | University of Groningen
Hodgkin lymphoma (HL) is characterized by constitutive activation of several signaling pathways and transcription factors, which is partly caused by gene mutations. To generate an overview of the mutational landscape in HL we performed whole exome-sequence (WES) analysis of 7 HL cell lines. Overall, we identified 463 genes mutated in 2 or more HL cell lines and 373 genes mutated in 2 or more classical HL cell lines. Based on SNPEFF_IMPACT, PolyPhen2 and SIFT analyses we showed that approximately half of the mutations have a putative damaging effect. As compared to Broad Institute data, an overall consistency ranging from 72.1% to 98.5% was observed. With the exception of the second deletion in SOCS1 reported in L1236, all mutations were confirmed. We identified mutations in HLA associated genes, B2M, HLA-A, HLA-DRB1 and in CIITA. Consistent with the B2M mutations affecting the ATG start codon, we observed no or very low membrane B2M and HLA class I expression in L428 and DEV by flow cytometry. B2M mRNA levels were reduced in both cell lines as compared to L1236, whereas HLA-A, HLA-B and HLA-C levels were in the same range. Our WES data revealed CIITA mutations in 2 of the 7 HL cell lines albeit with low read counts, that were confirmed by Sanger sequencing and also Broad data set. No significant enrichment of mutated genes in genomic regions with copy number gain or loss was observed. Combining mutation status with mRNA expression levels revealed a differential expression pattern in cHL as compared to germinal center B cells for 44 of the 373 genes mutated in cHL. In conclusion, we observed a high number of consistently mutated genes, with part of them mapping to regions with copy number gain or loss and part of them showing deregulated expression.
7 | Ee Soo Lee | University of Groningen
Replicative senescence alters the response of endothelial cells to haemodynamic force. Endothelial dysfunction where endothelial cells (ECs) acquire a pro-atherogenic phenotype is strongly correlated with arterial neointima formation and atherosclerosis. Hemodynamic force suppresses pro-atherogenic phenotype of ECs while it is promoted during vascular ageing. Previously, we showed that an extreme fibrotic form of endothelial dysfunction, endothelial-to-mesenchymal transition (EndMT), which is involved in intimal thickening, is inhibited by high shear stress (Moonen and Lee et. al., under revision). We showed that mechanotransduced shear forces regulate activation of MAPkinases that suppress EndMT. Little is known about the association between shear stress and vascular aging in endothelial dysfunction. We hypothesize that low shear stress predisposes, particularly senescent ECs to a pro-atherogenic phenotype. Expression of mesenchymal and endothelial markers was compared between low passaged (passage 7) and high passaged (passage 13 and above) human umbilical vein endothelial cells (HUVEC). The influence of low (2 dynes/cm2) and high (20 dynes/cm2) shear stress on phenotype and mechanosensing events in low and high passages of HUVEC were examined in EC medium and pro-fibrotic medium. In high passaged HUVEC, replicative senescence as shown by senescence-associated β-galactosidase staining and induction of p16 expression occurred. Replicative senescence was associated with the induction of mesenchymal markers expression, while expression of endothelial markers was decreased. Mesenchymal markers, particularly SM22α were highly expressed in non-senescent HUVEC under pro-fibrotic condition, while high shear stress suppressed their expression. In both EC medium and pro-fibrotic medium, low shear stress enhanced the induction of SM22α in senescent HUVEC but not in non-senescent HUVEC. In response to high shear stress, both types of HUVEC showed activation of ERK5 pathway, which suggests an atheroprotective mechanosensing event. Activation of SMAD1/5/8 pathway was detected in both non-senescent and senescent HUVEC exposed to low shear stress, which suggests an alternative pathway to proatherogenesis. In conclusion, ECs acquire atheroprotective phenotype in response to high shear stress, whereas low shear stress predisposes ECs particularly the senescent cells to a pro-atherogenic phenotype. Of note, the activation of ERK5 and SMAD1/5/8 pathways by high and low shear stress, respectively remained unaltered by replicative senescence.
8 | Gui Zhen Teoh | University College London
Development of nanocomposite trachea and bronchi scaffolds for paediatric applications. Introduction: Tracheal defects like congenital tracheal stenosis (CTS) and prolonged intubation following premature birth have resulted in an unmet clinical need. Advances in stem cell technology, tissue engineering and material sciences have inspired the development of our resorbable, nanocomposite trachea and bronchi scaffold. Materials and Methods: A trachea and bronchi scaffold was designed and constructed using our novel, resorbable nanocomposite polymer, Polyhedral Oligomeric Silsesquioxane Poly(ε-caprolactone) Urea Urethane (POSS-PCL), integrated with Polyhedral Oligomeric Silsesquioxane Poly(carbonate-urea) urethane for additional mechanical strength. Material characterisation studies included polymer viscosity, tensile strength, suture retention and contact angle. Bone marrow derived mesenchymal stem cells (bmMSCs) and human tracheobronchial epithelial cells (HBECs) were isolated, passaged and cultured on POSS-PCL and the metabolic activity was assessed by Alamar Blue® assay. Quantum dots conjugated to RGD peptides and anti-collagen type I antibody were then used to examine cell migration throughout the scaffold. Results: POSS-PCL exhibited good mechanical properties and the relationship between the solid and foam elastomers of the polymer was comparable to the relationship between the cartilaginous U-shaped rings and interconnective cartilage of the native human trachea. Good suture retention of the scaffold was also achieved. Isolation and in vitro culture protocols for bmMSCs and HBECs were successfully optimised. Cell attachment and a significant, steady increase in proliferation was observed, as illustrated by two-way ANOVA (bmMSC: p=0.001; HBEC: p=0.003). Antibody-quantum dot imaging illustrated cell penetration throughout the scaffold. SEM images confirmed the attachment and proliferation of both cell lines as well. Conclusion: Our mechanically viable synthetic scaffold provides a conducive environment for bmMSC and HBEC attachment and proliferation demonstrating its potential as a tissue-engineered solution to the increasing number of tracheal anomalies and pathologies in clinics.
9 | Jia Tsing Ng | University of Oxford
Visual inspection of crystallization experiments is an important yet time-consuming and subjective step in X-ray crystallography. While previous published work have focused on automatically classifying crystallization droplets into distinct experiment outcomes, a method is described here that instead ranks droplets by their likelihood of containing crystals or microcrystals, thereby prioritizing for visual inspection those images that are most likely to contain useful information. The use of textons to objectively describe crystallization droplets is introduced, allowing them to be scored with the posterior probability of a Random Forest classifier trained against droplets manually annotated for the presence or absence of crystals or microcrystals. When images are ranked for viewing according to these scores, so that droplets with probable crystalline behaviour are placed early in the viewing order, then for 94% of plates in a dataset of 196 plates imaged with a Minstrel HT system, the top 10 wells include at least one human-annotated crystal or microcrystal. This algorithm is robustly transferable to at least one other imaging system: applying the same parameters trained from Minstrel HT images to a dataset imaged by the Rock-Imager system, human-annotated crystals ranked in the top 10 wells for 90% of plates. Because the shape of the curve of scores is itself a useful overview of the plate’s behaviour, a custom viewer was written to integrate presentation of this curve with the display of images in their ranked order. Evidence that such ranked viewing of images results in more careful evaluation of drops with only microcrystals is also presented.
10 | Naila Azma Che Kamaruzaman | University of Reading
The development of forensic acarology and its reference collection. The application of mites in forensic investigation has received much attention in the recent years to provide forensically important information since mites have reported to be associated with dead bodies. The scope of forensic acarology goes further than the application of mites to estimate time of death, circumstances of death or relocation of dead bodies, particularly in conditions where insects are rare or absent. Mites can provide forensically important information to estimate the postmortem interval, post burial interval, cause of death and relocation of a dead body because they are microhabitat specific. And in fact because of their high diversity and abundance, they are of paramount importance in the analysis of trace evidence. However, the characteristic of mites and lack of expertise make mites one of the most overlooked pieces of evidence in forensic settings. In the mid 1800s, Dr. Jean Pierre Mégnin working at the Paris morgue, realised the importance of mites as markers of time of death, especially in cases with little or no insect activity. He analysed the arthropods colonising over 100 human corpses and documented his observations in “La Faune des Cadavres” [The Fauna of Carcasses]. Of the eight distinct waves of arthropods colonising human corpses, the first included flies and mites, but the sixth wave was composed of mites only. Despite representing a promising start for forensic acarology, his work remained ignored for a further 100 years. Since 2006, and thanks to funding support from the Leverhulme Trust in Britain, a group of researchers at UK Universities undertook the initiative of reviving and expanding the pioneering effort of Mégnin. By exploring the application of modern microscopical and molecular methods, the development of forensic acarology is taking shape, new protocols are being developed and assessed, and mites are analyzed in forensic settings, including crime scenes. The curation of the Forensic Acarology Reference Collection at the University of Reading is underway; this collection includes specimens from human corpses and animal carcasses, of criminal cases and research, covering five continents.
11 | Muhammad Zamir Othman | University of Bristol
Diamond: Future Material for Renewable & Sustainable Energy Production. Thermionic emission from diamond is a promising route for making thermal energy converters for use in solar power generation or energy harvesting devices. However, despite much recent progress, the production of high-current-density diamond thermionic emitters remains elusive. The most promising thermionic emission materials reported to date use nanocrystalline or even ultrananocrystalline diamond (UNCD) films, since it is believed that a high sp2/sp3–carbon ratio is essential in improving the electrical conductivity throughout the films. However, there is a trade off with the film thermal conductivity, a high value of which is necessary to transport heat from the heater at the base of the film to its emitting surface. Electron emission can be further improved by using n-type diamond, doped with phosphorus or sulfur, or n-type UNCD. Lithium has been suggested as a possible alternative n-type dopant due to its potential as a shallow donor in diamond. However, experimentally doping with lithium is difficult to achieve due to the low solubility of Li in diamond, and its relatively high mobility which allows it to diffuse through the lattice at fairly low temperatures. It has been suggested that the unwanted Li diffusion can be prevented by adding substitutional nitrogen together with interstitial Li, with the nitrogen acting as a trap to pin down the Li in the diamond lattice while retaining its n-donor properties. Calculations suggest that the optimum ratio of Li-to-N is 1:4, with LiN4 clusters acting as shallow donors. To study this, we investigated the incorporation of both lithium and nitrogen while growing microcrystalline diamond in a hot-filament chemical vapour deposition (HFCVD) system. Diamond thin films were grown using a methane/ammonia/hydrogen gas mixture with Li being added as solid LiN3 and overgrown with diamond. Secondary ion mass spectrometry showed that high levels of Li and N were embedded in the diamond and were situated in close proximity to each other. The crystallinity and morphology of the diamond films were unchanged by the Li/N incorporation. The diamond surface was hydrogen terminated. Thermionic emission measurements were performed on these Li-N co-doped diamond films and the results showed that emission began at a temperature of 500°C and gave a current of 124 µA/cm2 at 627°C, making it a promising thermionic material. We shall report the results of these studies, plus those from varying the Li:N ratio in a set of films to investigate the effect upon thermionic emission.
12 | Noratikah Othman | University of Reading
The Chaperone: Usher Translocon of Yersinia pestis F1 Capsular Antigen. Plague is a notifiable disease for which there is still no reliable vaccine available. This project is focused on understanding details of the structure and function of the Yersinia pestis F1 chaperone:usher translocon and applying this knowledge to export of heterologous epitopes. This study involved in silico and in vitro analyses; modeling of Caf translocon (IntFOLD2, iTASSER and PyMOL) and construction of Caf1 as a scaffold for export of heterologous epitopes (InFusion technology). The outer membrane Caf1A usher was modelled based on high resolution structures of 2 states of E. coli FimD. Based on the modelled translocon and identification of conserved residues within the usher plug, a conserved interaction between subunit (Asn81) and plug (Tyr287) was identified. The potential of F1 fibre to act as a carrier of epitopes was then tested by replacing 4 loops within Caf1 with either Gly residues ( pACYC-F1D11, -F1D12, -F1D13 and –F1D14) or a charged epitope (ELDKWA) (pACYC-F1::1, -F1::2, -F1::3 and -F1::4). Quantitation of heat extracted F1 from all constructs revealed that all constructs with Gly replacement assembled F1 on the cell surface. However, only F1D13 assembled as efficiently as wild type F1. Of constructs with the charged insert, ELDKWA, only one (F1::1) produced high levels of surface F1. Reduced export of the F1D12 and F1::2 constructs could be explained by a lost interaction, a clash of residues and possibly even a new interaction between Caf1A barrel and Caf1. Quantitation of F1 with cells carrying pACYC-F1::3 and pACYC-F1::4 were also showing low level of F1, 30.2%±4.18 and 8.9%±1.15 respectively. In contrast, export of F1::3 and F1::4 was blocked at an early stage as polymerisation of both constructs was disturbed. In conclusion, these preliminary studies indicate that loop 5 (F1D11/F1::3) of Caf1 appears to be the most efficient site for modification for heterologous translocate to the cell surface. Continuing studies will investigate optimal use of this and other sites, heat stability of modified F1 and antibody interactions. At the same time, mutagenesis of the barrel to suppress the export defect in non-exporting mutants will be investigated.
13 | Suraya Abdul Sani | Nottingham University
Is torcetrapib can be substituted by HCA in inhibiting Cholesteryl Ester Transfer Protein (CETP)?: A molecular modelling approach. Artherosclerosis is a multifactorial disease which caused by a long term process of an accumulation of lipids combines with an inflammatory response. The most promising strategy is to increase the HDL-c level by inhibiting the CETP function. Aim: The aims of this study is to see whether HCA does bind to the same active site as torcetrapib is and to see the stability of the ligand-protein binding. Method: Docking studies are carried out by using X-ray crystallography structure (PDB ID: 20BD and 4EWS) by using Glides software from Schrodinger Inc and validated results using GOLD. The molecular dynamic simulations are being carried out by Desmond (Schrodinger inc) by using the ligand-protein complexes from the docking results. Results: Based on the molecular docking studies, HCA does bind to the same residue as torcetrapib is and based on the MD simulation analysis, the binding of the ligand-protein complexes are stable throughout the simulation. Further verification on in vitro experimentation of HCA does shows the potency against CETP activity and the results are in consonance with the in silico studies. Conclusion: This study prepares a solid foundation on how the binding mode of HCA against CETP and the study of the mechanism of actions should be carried out in order to see the real interaction between CETP protein residue and HCA in increasing the HDL-C level.
14 | Jun Hon Pang | University College London
Antibody-Functionalised Nanocomposite Material as Next Generation Stent Coating with In Situ Endothelialization Capability. Background: Current clinically used coronary stents, i.e. bare metals stents and drug eluting stents are associated with considerable risk of restenosis and late stent thrombosis. Improving patency of these stents has been a thriving goal in cardiovascular medicine research. Regeneration of an endothelium layer is regarded as the ideal blood-contacting surface. In situ endothelialization serve as a promising approach to enhance long-term patency and could be achieved by capturing endothelial progenitor cells (EPCs) using EPC-capturing biomolecules. Materials & Methods: A novel non-degradable nanocomposite polymer, polyhedral oligomeric silsesquioxane-poly(carbonate-urea) urethane (POSS-PCU), which had previously demonstrated superior mechanical properties and anti-thrombogenicity, was selected as a coating material for coronary stents. Surface functionalisation of POSS-PCU was achieved by the creation of amine groups (-NH2) by coating of POSS-PCU pre-polymer containing isocyanate groups followed by chemical treatment. The surface was characterised using colourimetric assay, microscopy and whole-blood thromboelastography (TEG). EPC-capturing anti-CD34 antibodies were subsequently immobilised to the amine functionalised POSS-PCU (POSS-PCU-NH2) followed by characterisation using fluorescent secondary antibodies. Results: Amine functionalisation on POSS-PCU surface was confirmed and optimised via colourimetric assay and microscopy. TEG shows no significant difference in hemocompatibility between POSS-PCU-NH2 and pristine POSS-PCU surface. Characterisation using fluorescent secondary antibodies appears to confirm the immobilisation of antibodies onto the surface. We intend to elaborate further on the function and orientation of the antibodies after immobilisation. Conclusion: We have developed a new stent-applicable surface functionalisation method of a complex nanocomposite polymer, POSS-PCU, and have utilised this surface for antibody immobilisation for use as a coating for coronary artery stents. This platform could potentially be utilised for immobilisation of other biomolecules including peptides and growth factors for future investigation of in situ endothelialisation capability.
15 | Hasmawati Antong | Loughborough University
Modelling and building of experimental rig for high redundancy actuator. The high redundancy actuator (HRA) concept is a novel approach to fault tolerant actuation. It refers to an actuator that consists of relatively large number of actuation elements, connected both in series and parallel to form a single actuator. This configuration improves the reliability and availability of the actuator and thus provides a high degree of fault tolerance. The HRA also reduces the need for over-sizing an actuator especially in safety-critical applications such as aerospace. HRA is suitable to a wide range of actuation technology but this paper focuses on a linear electromechanical actuator (EMA) due to its extensive application not only in industrial machinery but in aircraft and the aerospace industry in general. This paper presents ongoing and future work to demonstrate the concept of a fault tolerant system high redundancy actuator through a 3-by-4 series-in-parallel linear electromechanical actuator.
16 | Zatul-‘Iffah Abu Hasan | University of Leeds
RF-amide peptides of the reproductive tissues of male dipteran insects. Peptides, operating as either modulators of adult behaviour or of muscle activity in reproductive tissues, can play important roles in the reproductive success of insects. Male accessory gland (MAG) peptides transferred in seminal fluid to the female during copulation can change both the reproductive physiology and behaviour of the post-mated female. We recently reported that the Aea-HP-1 (pERPhPSLKTRFamide) of Aedes aegypti that inhibits host-seeking behaviour of the female mosquito is made in the MAG and is passed to the female on copulation. We were interested to know whether structurally related peptides were present in male accessory tissues of other insects and have used both mass spectrometry and immunological approaches to look for peptides with similar -RFamide C-termini in several dipteran insects including Drosophila melanogaster, Drosophila suzukii, Drosophila yakuba and Drosophila erecta. Although we do not find evidence for synthesis of –RFamide peptides in the male accessory tissues of these insects, we do show that –RFamide related peptides are commonly expressed in motor neurons innervating the muscle of the ejaculatory duct and the MAG. We propose that these peptides play a role in the control and coordination of muscle activity responsible for the transfer of semen during copulation.
17 | Siti Fatimah Ibrahim | University of Leeds
Predicting the Deformation of Solid Particulates Materials Using Molecular and Synthonic Modelling Techniques. Direct compression is favourable in the solid dosage processing because of its simple and cost effective approach. Major issues of direct compression are related to the compressibility and flowability of the drug formulation. The molecular and synthonic engineering are applicable to give a quick and cheap prediction for mechanical properties for diverse solid forms. A ‘mechanical properties toolbox’, which is the combination of the crystal molecular and synthonic modelling test kits, is used in this study. The test kits include analysis of slip systems, calculation of slip surface rugosity, examination of hydrogen bonds breaking, appreciating the crystallographic patterns, and computing the energies associated to the surface-bulk of particulates. Each of the test kits, are associated to a specific program which are developed or available commercially. Software used are Materials Studio, GULP, VisualHabit and XRTD6. The case study systems are diverse solid forms of paracetamol. By observing the crystallographic pattern, all solid forms showed distinct differences in terms of interlocking or non-interlocking pattern. Further evaluations using the ‘mechanical properties toolbox’ demonstrated the behavior for each solid form that is potential to plastically deform or cleaved. The results obtained from the preliminary study showed that prediction of crystal structures mechanical properties with regards to its crystallographic structure is sensible in showing the occurrence of deformations. Hence, the prediction of mechanical properties is reliable to facilitate the solid dosage selection for used in direct compression.
18 | Cheong Sek Shir | University College London
Purpose: CHRDL1 mutations have previously been reported to cause X-linked megalocornea (MGC1). In this study, eight MGC1 families were ascertained and screened for CHRDL1 mutations. Megalocornea is also a key pathognomonic feature of Megalocornea-Mental Retardation (MMR) syndrome. MMR is a rare, phenotypically heterogeneous condition and the underlying genetic cause(s) are unknown. We therefore performed whole exome sequencing (WES) to identify the causative gene(s) in a male patient diagnosed with MMR. Methods: After informed consent was obtained genomic DNA was isolated from whole blood. All coding exons and splice sites of CHRDL1 were amplified by PCR, followed by Sanger sequencing. WES was performed for the MMR patient. The WES dataset was filtered for rare variants with a minor allele frequency ≤0.01 and cross-referenced with genes that have been reported to cause intellectual disability, hypotonia or seizures that are features of MMR. This dataset was generated with reference to the KEGG disease database. Candidate variants were then validated by PCR and Sanger sequencing. Results: In each MGC1 family, a novel CHRDL1 mutation was identified which included nonsense mutations (p.Cys80X and p.Cys99X), missense mutations (p.Cys289Arg and p.Cys291Tyr), a frameshift mutation (p.Glu101Glyfs*42), a splice site mutation (c.1247_1247-1delGG) and an entire CHRDL1 gene deletion. Interestingly, analysis of the WES dataset for the MMR patient resulted in identification of a novel missense mutation in CHRDL1 (p.Cys155Tyr) that was subsequently validated. The mother of the MMR proband was found to be a carrier of the CHRDL1 mutation. Although his ocular phenotype could therefore be attributed toCHRDL1, his non-ocular phenotypes (including intellectual disability and seizures) are unlikely to be caused by CHRDL1. The WES dataset was also interrogated for rare variants in genes known to cause these conditions, but no likely causative mutations were identified. Conclusions: All MGC1 families investigated were found to have a mutation in CHRDL1. The missense mutations identified are located at conserved cysteine residues within von Willebrand factor C domains. We describe the first mutation causing the ocular component of MMR syndrome. CHRDL1 screening in other male MMR patients will reveal the contribution of mutations in this gene.
19 | Maizatul Suriza Mohamed | University of Nottingham
Analysis of genetic variation in Phytophthora palmivora, the causal agent of bud rot disease of oil palm. Phytophthora palmivora has recently been identified as the causal agent of bud rot disease of oil palm in Latin America with severe outbreaks reported in Colombia, Brazil, Ecuador, Panama and Suriname. This disease has been responsible for the losses of thousands of hectares of oil palm in this region. However, no outbreaks of the disease have been reported in Malaysia or other Southeast Asian countries despite the fact that P. palmivora is a common pathogen in this region on other plant species. Sequence analysis and amplified fragment length polymorphism (AFLP) are being carried out to investigate the genetic diversity and variation of P. palmivora isolates from around the world and from different hosts in comparison Colombian oil palm isolates, as one of the steps in understanding why this species of Oomycetes causes devastating damage in oil palm in Latin America but not in other regions. 25 isolates of P. palmivora has been collected from cocoa, coconut, durian, rubber, betel palm, kentia palm and cymbidium from various places such as Malaysia, Indonesia, Sri Lanka, India and Ghana. Sequence analysis of internal transcribed spacer regions (ITS) of the ribosomal RNA gene cluster has been carried out using ITS1 and ITS4 primers and sequences alignment showed no distinguishing differences between P. palmivora isolates. However, with AFLP analysis, variations within P. palmivora isolates can be observed based on the banding patterns on agarose gel electrophoresis and fragment analysis. AFLP is a PCR-based fingerprint technique that is widely used to study biodiversity of organisms at the molecular level without knowing the sequences of the studied organisms, and has proven useful for investigating genetic variation among individuals. Restriction enzymes, EcoRI and MseI have been used for genomic DNA digestion prior to PCR amplification in the AFLP technique. 27 primer combinations have been tested and 8 primer pairs (EcoRI-A+Mse-AG; EcoRI-A+Mse-GA; EcoRI-A+Mse-CAT; EcoRI-A+Mse-CAA; EcoRI-A+Mse-CTG; EcoRI-AA+Mse-CAA; EcoRI-AA+Mse-CTG; EcoRI-AA+Mse-CAT) have shown good banding patterns for P. palmivora and gave distinctive patterns compared to P. cryptogea and Trichoderma viride.
20 | Khairil Anas Md Rezali | University of Southampton, Universiti Putra Malaysia
Background: Long exposure to vibration emitted by powered tools can cause serious injuries in the fingers and the hands of the tool operator, known as the hand-arm vibration syndrome. Previous research has shown that the materials used in anti-vibration gloves are capable of attenuating vibration transmitted to the hand of the tool operator. Transmissibility of a glove to the hand primarily depends on two factors, the driving response of the hand (i.e apparent mass of the hand at the tool handle) and the dynamic stiffness of the material in the glove. However, the mechanism of how vibration is attenuated by the glove is still not clear. Objective of the study: The objective of this study is to advanced understand factors that influence the transmission of vibration through gloves to the hand. Method: This was done by measuring and modeling the biodynamic response of the hand and the arm. The effects of contact force, contact area, and material dynamic stiffness on the glove transmissibility to the hand were studied. Findings: The findings of this study suggest that the effective way of improving a glove efficiency in attenuating vibration is to increase contact area and contact force of the hand but decrease the material dynamic stiffness (i.e by decreasing the contact area). The increase and the decrease of these three variables are needed to be ‘balanced’ to avoid ‘no-contact’ or material from bottom-out. Conclusion: It is recommended that a glove is design and assessed based on frequency of vibration of the vibrating tool, contact area as well as contact force required to operate the vibrating tool. The inclusion of the mass of the human body in the assessment of a glove transmissibility may overestimate the attenuation of vibration of a glove at low frequencies of vibration. This study however has excluded the effects of hand-arm posture and vibration direction which may give a great effect on the apparent mass of the hand.
21 | Chun Hao Wong | King’s College London
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that primarily targets the motor neuron system. ALS is generally considered as a complex disease with multiple rare and lowly penetrant genetic causes identified in a few individuals. The most common genes known to cause dominantly inherited adult-onset ALS are SOD1, TARDBP, FUS and C9orf72 expansions. Most ALS cases are sporadic (SALS) but 5% are familial (FALS) with a first- or second-degree relative with ALS or frontotemporal dementia. Despite several breakthroughs in recent years, approximately 45% of FALS cases still have unknown genetic aetiology. As FALS and SALS are indistinguishable both clinically and pathologically, gene hunting in familial disease is important to gain further insights into the much more common sporadic cases. To identify novel candidate genes, to date we have conducted extensive exome capture and next generation sequencing of approximately 200 UK cases and 550 collaborators samples. Using this approach, we have identified several clustered gene mutations in a RNA binding protein. We aimed to model these mutations at cellular level with focus on pathological hallmark of ALS respectively protein solubility and cellular localisation. Our preliminary results suggest that these mutations could contribute to ALS development through influencing fundamental protein-protein interactions. Investigation into these rare novel variants would provide promising insights into the genetic architecture and variation in the pathogenesis of motor neuron degeneration.
22 | Amirah Zaki | University College London
Enhanced expression of conjunctival IL-9 co-localized with mast cells in seasonal allergic conjunctivitis and its effect on mast cell cytokine secretion via IL-9R. Purpose: Mast cells (MC) are well known as the primary responders in allergy, secreting pro-inflammatory mediators including cytokines into the extracellular environment. IL-9 is a pro-inflammatory cytokine that is associated with the immunopathogenesis of allergic diseases including asthma. However, its role in allergic conjunctivitis is still unknown. The aim of this study was to investigate conjunctival expression of IL-9, and its role in cytokine secretion by mast cells. Methods: Human anonymised conjunctival tissue biopsies (3µm) were obtained from SAC donors (n=8, from all males; age: 18-65 years) at 8 hours’ post allergen challenge, and normal, non-inflamed, conjunctival tissues from anonymised donors (n=8 from 3 males; age 31-57 years). Donor tissues were collected after obtaining informed consent and Local Ethics approval in accordance with the Declaration of Helsinki. Sequential tissue sections were stained for anti-human IL-9 (Abcam), anti-human MC tryptase (AA1;DAKO) and primary antibody was omitted as a negative control. Two independent, masked observers enumerated positively stained cells per biopsy area (at least three fields). To study the function of IL-9 in vitro, bone marrow derived murine mouse mast cells (BMMCs) were exposed to PMA/ionomycin, ionomycin alone or anti-IgE in the presence or without anti-IL-9 or anti-IL-9R antibodies (R&D). Cytokine secretion at 24, 48, 72, 96, and 120 hours was assayed using multiplex bead arrays (Luminex). Results: IL-9 expressing cells were detected mainly within the subepithelial and stromal areas. There was a significant increase in numbers of IL-9+ cells in SAC tissues (mean=10.25 ± 1.26) compared to controls (mean= 25.00 ± 3.72; P<0.01). MC numbers were increased in SAC tissues and co-localised with IL-9. IL-9 was detected 24 hours’ post stimulation and reached its maximum at 48 hr in response to PMA/ionomycin and anti-IgE and 96 hr in response to ionomycin. Following neutralization of IL-9, IL-4, IL-5 and IL-13 secretion was upregulated but these cytokine levels decreased upon blocking IL-9R (P<0.05). Conclusion: IL-9 expression within conjunctival tissues was upregulated during challenge and is secreted by mast cells. In vitro studies revealed that IL-9 affects IL-4, IL-5 and IL-13 secretion from BMMC.
23 | Khairunnisa Mohammed | University of Cambridge
Purification and characterization of mitochondrial complex I from different tissues of Rattus norvegicus. Mitochondrial complex I (NADH:ubiquinone oxidoreductase) is an entry point of electrons into the respiratory chain. It oxidizes NADH, reduces quinone, and couples the redox process to proton translocation across the inner mitochondrial membrane. Numerous diseases have been reported to arise from defects in complex I, ranging from muscular to neurodegenerative diseases. Complex I has a unique L-shaped structure, containing 14 conserved ‘core’ subunits that have been identified in bacteria to eukaryotes. Complex I from bovine heart has been used as a mammalian enzyme model for complex I studies, and 30 additional ‘supernumerary’ subunits have been identified in it. However, it is not known how the subunit compositions of complex I from different mammalian tissues may vary. Rat (Rattus norvegicus) is a popular in vivo model for studying mitochondrial dysfunction and other diseases, providing a model for comparison of various tissues to study complex I using minimum materials. Here, tissues were obtained from the rat skeletal muscle, heart, kidney, liver and brain and used to prepare mitochondria and purify complex I. As there is no published protocol for obtaining highly-pure catalytically-active complex I from rat tissues, the standard bovine heart complex I isolation protocol was used initially, and modified to suit the small scale purification. A microscale purification system consisting of three chromatographic steps was applied in order to obtain the best resolution, recovery and purity from small amounts of material (down to 0.5 g tissue). The catalytic activities were assessed and the polypeptide composition of each complex I from each tissue was identified and compared by mass spectrometry.
24 | Nurul Nadiah Hamidon | University of Groningen/Universiti Malaysia Pahang
The advancement of paper microfluidics offers an undeniable solution for diagnosis in low resource settings. Multiple glucose and protein assays can be conducted simultaneously by simply introducing a drop of urine or fingerpricked blood on a stamp-size paper device. The ability of paper to propel liquid movement through readily available capillary action eliminates the need of external pump, thus keeping the design simple. The movement of liquid can be guided to a particular location on the paper, either to react with a particular reagent or undergone extraction, by patterning barriers. Previously, constructing pattern on paper using wax dipping technique produces wax barriers that are not very robust due to adherence attributed only by physical bonding. The consistency of melted wax is also affected by the type of wax used, heating temperature and prolonged heating, thus varying the wettability of wax on paper. Often it is difficult to obtain uniform layer of wax when mask with small opening is used to construct pattern on paper. In this work, patterning technique using hydrophobic agent called alkyl ketene dimer (AKD) with subsequent exposure to oxygen plasma is proposed. Chromatography paper was first coated with AKD solution and cured in oven for 30 min. To construct desired pattern on the paper, 3D-printed mask was applied to the coated paper were exposed region will undergo treatment with oxygen plasma. Coating of paper with AKD solution produced surface that is impermeable to water. Upon exposure to oxygen plasma, unmasked surface regains its hydrophilicity, while the masked region remains hydrophobic. Interestingly, the hydrophility of the surface increases with duration of exposure. This suggests that the wettability of surface can be manipulated to control the speed of fluid flow. Because of the high diffusion of oxygen plasma and good control of treatment process, patterns of high resolution and reproducibility was achieved on paper. Chemical bonding of AKD to cellulose produces a more stable coating and expected to maintain its surface property over a long period of time.
25 | Haijie Tan | University of Oxford
Nano-electronic devices based on 2D materials. The birth of 2D materials was marked by the discovery of graphene by Nobel laureates Geim and Novoselov in 2004. Made of only one layer of carbon atoms, graphene is found to have excellent electromechanical properties including high strength, flexibility, transparency and electron conductivity. 2D materials, with unique properties unseen in bulk materials, are promising candidates in making faster, denser and more efficient integrated circuits used in computer chips. Furthermore, doubled with their two-dimensional nature, 2D materials also pave way for a new generation of transparent and bendable electronics, with applications such as flexible solar cells, wearable health monitors and contact lens computer. The focus of our research is to make field-effect transistors (FETs) based on 2D materials, which will act as a switch that produces the “0” or “1” signal within a logic circuit. To do so, a thorough understanding of the electronic behaviours and interaction between the layered 2D materials will be essential. We have synthesized 2D materials including graphene (semi-metal), boron nitride (insulator) and tungsten disulfide (semiconductor) using chemical vapour deposition (CVD) process, and have studied the atomic structures of these 2D materials using transmission electron microscopy (TEM). Nano-electronic devices are fabricated using electron-beam lithography, allowing features as small as a few microns. We have also investigated the charge transfer and contact interaction between tungsten disulfide and graphene using field-effect measurement and optical characterization such as Raman and photoluminescence analysis. These experiments aim to elucidate the structure-property relationship of devices based on 2D materials, and contribute to more effective designs and fabrication processes of novel electronic devices.
26 | Raja Ili Airina binti Raja Khalif | University of Southampton
Friend or Foe? : Embryo freezing in assisted reproductive technologies (ART). The effect of freezing on subsequent mouse embryo development and postnatal health Embryo freezing, an integral part of IVF routine, proved to be the ultimate solution for infertile couples. In 2013, it is estimated that 5 million babies have been born following ART worldwide1. As the use of embryo freezing and IVF increases worldwide, it is important to consider the possible risks involved as well as the unknown potential long-term consequences on the IVF children. Objectives: (i) To determine whether freezing procedures would affect the number of cells in embryos (ii) To compare the postnatal growth, cardiovascular and metabolic health between the controls and the frozen embryos offspring. Materials and Methods: Using mouse model, frozen embryos underwent vitrification procedure before cultured and developed to blastocyst that will give rise to a proper foetus if implanted to a surrogate mother. Embryo transfer (ET) were carried out. Offspring were then monitored and data were collected until week 27. Results and discussion; There is a significant differences (p<0.05) between the cell number of the control compared to the frozen embryos. Currently, offspring body weight between naturally-mated (controls; n=81), non-frozen ET (n=43) and frozen ET (n=27) showed significant differences in male and female offspring from week 4 and 7 (p<0.05); respectively. Mean systolic blood pressure showed significant differences (p<0.05) in male and female offspring between control and other treatments in week 21. Conclusions: Embryo freezing may affect long-term growth of offspring into adulthood. Future works: Derivation of embryonic stem cell (ESc) from the frozen embryos will be carried out and analysis on gene expressions and epigenetic findings might then linked to the different phenotype that were observed in the offspring earlier. Funding EU FP7 EpiHealth and Malaysian government (MARA).
27 | Amirul Hakim Noor Haizat | University of Cambridge
Identification of BES1 functional partners involved in regulation of xylem differentiation. Vascular plants have adapted to a variety of environments ranging from arid deserts to tropical rainforests. The vascular system which they have in common is important for water and nutrients transportation throughout the organism via xylem and phloem. During plant radial growth, meristematic cells in the vascular system either self-proliferate or differentiate into xylem cells. These two processes are regulated by a signalling pathway that involves a peptide ligand, TDIF and its cognate TDR receptor. In this study, our results were consistent with role of BRI1-EMS SUPPRESSOR 1 (BES1), a downstream component of the TDIF-TDR signalling pathway, as a promoter of xylem differentiation. It has been proposed that BES1 functions as a heterodimer with other factors to regulate xylem differentiation. Thus, we selected five candidate BES1 partners and tested for physical interactions with BES1 by using bimolecular fluorescence complementation (BiFC). We observed positive results for four genes tested. To support our results further, we checked for any xylem differentiation phenotype by overexpressing the candidate genes in a constitutively active BES1 mutant background in Arabidopsis thaliana. We observed phenotypes for two of the candidate genes. In conclusion, the two genes narrowed down are possibly BES1 partners. These findings provide insight into the regulation of cell fate determination in meristem maintenance.
28 | Fara Yahya | University of Southampton
More and more data are stored in the personal cloud storage and it is expected to grow further. As cloud storage are becoming an option for user in keeping their data online, it comes with the security threats and the challenges of protecting their data from unauthorised accessed. Many security controls have been implemented by cloud storage providers (CSPs) as a security measure but although encryption is known as one of the solution, it cannot be fully implemented due to the need of a robust and costly infrastructure. Therefore, we foresee the need to implement protection based on categorisation of data determined by users. We propose a security framework that protects data in cloud storage based on the level of protection it needs. This will also enable the implementation to be more flexible as it will offer multi layers of security only to a group of data that requires it. This paper will discuss recent security threats and also the levels of data protection in cloud storage. It is essential to look into these security threats and ways to protect our data as cloud storage is an evolving technology with security considerations. We aim to protect data in personal cloud storage in enhancing cloud storage security implementation.
29 | Nuzul Jambari | University of Nottingham
Allergenicity Of 2S Albumin Proteins: In Vitro Studies On The Uptake And Molecular Mechanisms Of Bmdcs Upon Stimulation With Ber e 1 AND SFA8. In order to study the intrinsic allergenicity of food proteins, the storage 2S albumin Ber e 1, the major allergen from Brazil nut (Bertholletia excelsa) and the related but weak allergenic SFA8 from sunflower seeds (Helianthus annuus) were used as model proteins. Both P. pastoris-expressed recombinant Ber e 1 (rBer e 1) and SFA8 (rSFA8) were shown to mimic their native counterparts in structure, biophysical characteristics and immunoreactivity. However, rBer e 1 is mannosylated whereas native Ber e 1 (nBer e 1) is not. Glycosylation of proteins has been shown to increase immunogenicity of antigens and characterised as allergenic Th2 adjuvant in other systems. This study aimed to determine whether glycosylation plays a role as an antigenic determinant for Ber e 1. The glycosylation pattern of rBer e 1 and nBer e 1 extracted from Brazil nut were characterised by mass spectrometry (MS). MS analysis indicated mannose residues present in rBer e 1. This mannose modification, however, is not detected in nBer e 1. Murine bone marrow-derived dendritic cells (BMDCs) endocytosis assay analysed by FACS showed that the uptake of both mannosylated and non-glycosylated proteins were mainly via macropinocytosis. However, the uptake of rBer e 1 was also assisted by mannose specific-C-type lectin receptor (CLR)-mediated endocytosis, which increases the endocytosis rate of the mannosylated rBer e 1 by 3-fold compared to nBer e 1 or rSFA8. The confocal imaging showed that the rBer e 1 did not co-localise with the nBer e 1 but co-localise withrSFA8 in dendritic cells during the early phase of endocytosis. The results so far suggested that mannosylation of rBer e 1 affects the immunogenicity of protein via enhancing the endocytosis rate and changing the route of uptake of protein by DCs compared to its natural counterpart. However, mannosylation of rBer e 1 might not be the main feature responsible for the DC polarisation observed. Stimulation of bmDCs with nBer e 1 and rSFA8 resulted in polarised DC programming that affect DC maturation and TH1/TH2 polarising cytokines. Further transcriptomic profiling was performed to establish the exact molecular mechanisms involved in determining the allergenicity of Ber e 1 and SFA8.
30 | Erni Mariana Mukhtar | University of Southampton
Drivers of sustainable waste management are defined as forces that influence the development and may have changes or effects on the existing waste management system. Many research papers have categorized drivers into various types; however, little attention has been given to factors that insignificantly contribute to the efficient waste management. Drivers that have significant impact onto waste management efficiency can be addressed as visible factors. In this context, drivers can be considered as positive (accelerators) or negative (barriers) depending local waste scenario. On the other hand, supporting drivers are the factors that commonly seen as insignificantly important in the waste management can be addressed as invisible factors. The strength of invisible factors in waste management system maybe varies depending on local waste scenario. Although these factors are often been neglected from the waste management system loop, it may produce significant impact in waste management systems if it is been given attention in the local waste scenario. This paper attempted to critically review the key factors that create opportunities/barriers effecting waste management systems in large urban areas, focusing on rapidly urbanized cities. In addition, it is also investigated on how visible and invisible factors interact to impact the current waste management system and how they might contribute to improve future systems. The finding of this study is expected to portray the interactions of all these factors with the policy implications towards obtaining sustainable urban planning in rapidly developed cities.
31 | Choong Siew Shean | University of Nottingham
Comparative Transcriptomics in Adipose Tissue of Meishan & Large White Pigs. Introduction: Meishan sows have been recorded to outperform the Large Whites (LW) reproductively. The higher percentage of body fat in the Meishan compared to that of the LW may be an important factor, as adipose tissue has been reported to be pertinent in regulation of the hypothalamus-pituitary-gonadal axis. To test this hypothesis, next generation sequencing was used to generate transcriptomes of adipose tissue from Meishan and LW neonates (7-day old); these were compared to demonstrate differential expression of genes for adipogenesis and fat metabolism between these breeds. Additionally, adipose tissues from 7-day and 6-month old LW were compared to examine the influence of age. Methods: 7-day old Meishan, 7-day and 6-month old LW female pigs were euthanised, and subcutaneous adipose tissue was collected. RNA was extracted using Qiagen RNeasy Mini Kit, followed by quality evaluation with Agilent 2100 Bioanalyzer. RNA transcription was measured utilising RNA-Seq (Illumina HiSeq). A total of 61,746,166 (Meishan), 63,614,313 (7-day LW), and 61,180,967 (6-month LW) paired reads were obtained. Differential expression of genes was analysed using edgeR (www.bioconductor.org/packages/release/bioc/html/edgeR.html). qPCR was used to validate the sequencing results. Results & Discussion: Lower expressions of adipogenic factors such as leptin (LEP), uncoupling protein 2 (UCP2) and vitamin D regulator (VDR) were detected in Meishan compared to LW, with fold changes (FC) of 2.34, 2.79, and 2.41 (P<0.05) respectively. Comparison between 7-day and 6-month old LW revealed higher leptin receptor (LEPR), but lower cellular retinoic acid binding protein 2 (CRABP2) and retinol binding protein 5 (RBP5) expressions in 6-month old animals (FC = 5.10, 6.37, and 3.17 respectively; P<0.05). CRABP2 and RBP5 expressions were investigated as they were reported to affect adipogenesis. Results suggest a role for these genes in dissimilarities in adipogenecity between the breeds and age groups, which could lead to an understanding of differences in reproductive performance of the Meishan and LW.
32 | Syatirah Abdullah | Newcastle University
Larygectomy patients undergo voice rehabilitation that requires implantation of tracheaesophageal speech valve (TESV). The shunt-one way valve is positioned between the trachea and oesophagus, creating a tracheoesophageal fistula to assist in the production of sound. Usually laryngeal cancer patients require insertion of these devices post-operatively to improve their quality of life. Implantation of TESV dates back to 1979 by pioneering work of Blom and Singer. However, TESV may only last for couple of weeks because of biofilm development that obstructs the function of the valve.
Previous study reported that biofilm community on TESVs consists of Candida sp. and several bacterial species, such as Bifidobacterium infantis, Enterococcus faecium, Lactobacillus sp. and Streptococcus thermophilus. There are also oral origin strains that include; Rothia denticariosa, Stomatococcus mucilaginosus, Streptococcus mitis, Streptococcus sobrinus and Streptococcus salivarius.
33 | Amanda You Yi Fen | Imperial College London
Characterisation of human cardiovascular tissue in calcific disease using Raman and scanning electron microscopy. Calcification of human tissues occurs naturally in bone, deep zone of the cartilage and teeth. However certain pathological processes can result in ectopic soft tissue calcification. A better understanding of the structures and nano-scale architecture of ectopic calcification, as well as the extracellular matrix composition in tissues such as aortae affected by arteriosclerosis and other calcific diseases can lend insight into the biomineralisation mechanisms. Here, aortae, aortic valve, and coronary artery samples from healthy human donors and patients were analysed using Raman spectroscopy and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS). A previous study in our group identified spherical calcium phosphate deposits within aortic tissues of diseased and even healthy donors. These spherical deposits are a highly crystalline form of calcium phosphate, which differs from bone mineral in both its crystallinity and structure 1, 2. In this study, further characterisation with Raman mapping of the aortic wall supports these results based on intensity heat maps of the 960 cm-1 calcium phosphate and the 1080 cm-1 phosphate band, indicating discreet regions of calcium phosphate deposits within the tunica media of the aortic wall tissue. Furthermore the mineral composition of the calcified spheres was determined to be similar to whitlockite as found by Raman, EDS, and ICP, in stark contrast to calcifications of atherosclerotic plaques and bone mineral, which are poorly crystalline apatite. Interestingly, this is true for calcified spheres of the tunica media in both healthy and diseased tissue, suggesting the same origin. Differences in the chemical composition of the surrounding tissue matrix were also analysed to find a relationship between matrix composition and presence of mineralisation. In conclusion, this study indicates that the calcification in vascular tissues is different from that of bone. The characterisation and study of these tissues can thus contribute to a better understanding of pathophysiological tissue calcification processes and can have important implications in the field of cardiovascular disease.
34 | Suseela Yelumalai | University of Oxford
The effect of cryopreservation upon total levels of protamine, a key sperm nuclear protein responsible for maintaining DNA integrity, in mouse sperm. Introduction: Human infertility is becoming a significant global health problem and is generally estimated to affect 1 in 7 couples. While Assisted Reproductive Technology (ART), which implements sophisticated treatments such as in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) can now treat many cases of infertility, and has accounted for over 5 million babies thus far, success rates rarely exceed 30%. The mechanisms underlying the efficiency of ART are multi-factorial, but are generally associated with the manipulation and treatment of gametes in an artificial in vitro environment. Evidence is emerging to suggest that routine ART laboratory techniques, such as cryopreservation, may induce detrimental effects upon sperm structure, sperm DNA integrity, and the expression of sperm proteins that play a vital role in successful fertilization. Protamines are a group of proteins expressed in the sperm nuclei and play a critical role in DNA packaging leading to the formation of a hydrodynamic sperm structure and the maintenance and protection of paternal genomic DNA prior to fertilization. Mounting evidence suggests that alterations in the total levels of P1 and P2 are strongly related to male factor infertility via association with poor semen quality, increased levels of DNA fragmentation, and embryonic death. Aims Of The Study: We aimed to investigate whether a routine cryopreservation technique could detrimentally affect the total levels of P1 and P2 in mouse sperm. Methods: Comparative analyses were performed to evaluate the total levels of P1 and P2 between non-cryopreserved and cryopreserved sperm extracted from the caudal epididymi of 16 week old mice, (n=5) using immunocytochemical technique. Results: Current findings clearly indicate a significant reduction, by up to 50% (P ≤ 0.05, as determined by One-way ANOVA) in the total levels of P1 and P2 in cryopreserved mouse sperm as compared to non-cryopreserved sperm. Conclusions/Discussion: Future studies will extrapolate such findings to human sperm, and to link these observations to specific tests of DNA integrity and fragmentation. It is possible that the quantification and characterization of protamine may serve as a biomarker for the selection of sperm exhibiting the best quality, integrity and function, for subsequent ART treatments.
35 | Pollux Sii | Heriot-Watt University
The Role of Punctuated Subsidence and Structural Inversion in Creating the East African Spice Islands of Zanzibar. The Tanzanian margin has been historically been considered a passive margin with no active structuring since the rifting of Madagascar from East Africa. A period of tectonic stability and gentle subsidence followed, lasting through to the Oligocene. However, seismic interpretation works using an array of 2D grids and 3D seismic volumes from the Indian Ocean and adjacent areas, shows that the Neogene tectonic evolution of the margin may be more complicated. The peculiar presence of the three largest island offshore Tanzania i.e. Pemba, Zanzibar and Mafia may be structurally related. Anticlinally cored with Miocene sediments and growth of sedimentary packages at hanging wall of large faults which are now elevated above regional compared to footwall suggest that these islands are likely to be once submerged and recently uplifted. A number of competing possibilities have been considered and discounted. It is proposed that punctuated period(s) of compression could have took place as early as Late Miocene leading to the inversion of Miocene growth faults, emerging the islands as a positive structure in a generally subsiding coastal region. The inversion structures are not massive and still in net extension. Broad folding structures evident in offshore areas support this theory as well. Opening of the East African Rift System (EARS) in the Miocene may have reactivated the basin reflecting a period of rejuvenation of pre-existing extensional faults and a post-Miocene re-establishment of Tanzanian passive margin. Research is now inquired in the following directions: 1. Tectonic drivers that lead to the compression in this ‘passive margin’ – ridge push effects due to opening of EARS; high spreading rates in Late Miocene; or development of topographical high in EARS generating sufficient horizontal stresses to deform the margin. 2. Acquire more seismic data on and inboard of the islands to provide a more solid evidence to support the inversion hypothesis. 3. Additional well data to fully constraint the ages of horizons allowing stratigraphic correlation to capture accurate timing of inversion. 4. Assessment of plate margin and intraplate stresses.
36 | Zaiton Abdul Majid | Universiti Teknologi Malaysia
Carbon-Based Nanostructures For Reinforcement Of Cementitious Matrix. The incorporation of carbon nanostructures in cementitious environment is expected to provide a nanoscale reinforcement, thus shifting the reinforcement from macroscopic to nanoscopic scale, resulting in better mechanical properties. Our research focuses on the effect of three types of carbon nanostructures namely pristine MWCNTs (p-MWCNTs), surface-modified MWCNTs (f-MWCNTs) and cellulosic aerogel (CA) on the chemical and mechanical properties of hardened cement paste (HCP). The CA was synthesized by boiling and digesting wastepaper using sodium hydroxide until gelation occurred, followed by supercritical drying process. The amount of each carbon nanostructures was fixed at 0.03% (w/w) of cement and at a water-to-cement ratio of 0.33. The hardened samples were cured in humidity cabinet and evaluated via FTIR, XRD, SEM-EDX and compressive strength at 7, 28 and 56 age. The initial setting time of the samples performed in accordance to ASTM C191-08 showed that the setting time achieved were within the acceptable limit. Generally, it can be seen that the incorporation of carbon nanomaterials showed enhancement in the compressive strengths. The FTIR spectra of HCP and carbon composites showed that CA-cement and p-MWCNTs cement composite yield approximately similar hydration spectra to HCP, suggesting that the hydration of cement was not affected with the incorporation of p-MWCNT and CA. Similar observations were observed for the XRD data. Field Emission Scanning Electron Microscopy (FESEM) showed bridging of voids between MWCNTs and the neighbouring cement particles surrounded by their hydration products. This could explain the significant increase in the mechanical strength of the composite pastes compared to the paste prepared from the plain cement. Morphology of CA-cement composites showed that cement hydration products were entangled within the cellulosic aerogel thus filling voids, causing the paste to harden in between the honeycomb-shaped fibrillar network resulting in denser cement composite.
37 | Ka-Liong Tan | University of Oxford
Expression of Targeted Neddylated Pathway Proteins In Cancer Cells Under Hypoxic/Reoxygenation Condition. AIPL1 (Aryl hydrocarbon receptor-interacting protein-like 1) is the member of the FK506 binding protein family. It interacts with NUB1 (NEDD8 ultimate buster 1) and subsequently downregulates the NEDD8 expression through its conjugation system. Overexpression of NUB1 induces a inhibit cancer cells’ growth, the mechanism actions of NUB1 in cancer cells remain uncertain. The aim of the study is to examine the variable expressions of these proteins in the targeted NEDD8 conjugation pathway in cancer cells. Five human breast cancer cells, two renal cancer cells and two liver cancer cells were used for this study. The expression of cancer cells under normal condition was measured by westernblot and quantitative reverse transcriptase PCR. Cells were harvested and lysates were prepared in accordance with the manufacturer’s instructions. Protein samples (20 µg of each protein) were treated at 95°C for 5 mins with β-mercaptoethanol and separated in 10% SDS–polyacrylamide gels and transferred onto nitrocellulose membranes. Membranes were blocked for 1 h at room temperature with PBST and probed overnight at 4°C with primary antibodies under manufacturer-recommended conditions. Immunoblots were washed with PBST and incubated with secondary antibodies conjugated with horseradish peroxidase against mouse IgG or rabbit IgG for 1 h at room temperature. Each western blot analysis was performed in duplicate. All AIPL1, NUB1 and NEDD8 messenger RNA and protein varied among the selected cancer cell lines. Differential expression of these proteins will be discussed in detailed. In future studies, cell cycle profile in cancer cells will be examined and associated with the apoptotic profile.
38 | Janice Shing Wei Ng | University of Cambridge
Investigating the biophysical properties of TDP-43 aggregates in Amyotrophic Lateral Sclerosis (ALS), a motor neurone disease. The aggregation and deposition of transactivation response DNA-binding protein 43 (TDP-43) in motor neurons is a key pathological feature in nearly all amyotrophic lateral sclerosis (ALS) cases. To date, a detailed analysis of the dynamic processes leading to TDP-43 aggregate deposits in live cells has not been reported. We have established neuronal cell lines that express the full length or C-terminal fragment (residue 274-414) of TDP-43 tagged with a tetracysteine (TC) motif that binds specifically to membrane-permeable biarsenical dyes (FlAsH and ReAsH), and we are comparing this to a cell model expressing TDP-43 fused to green fluorescent protein (GFP). Using confocal microscopy, we demonstrate that biarsenical labelling technique enable the visualisation of TDP-43 localisation for both the monomers and aggregate formed within live mammalian cells; in particular we can monitor the changes in distribution and aggregation as a function of time. Purified recombinant CTF-TC show to form fibrillar aggregates, which might be an important cause of ALS. This in vitro model will allow us to compare the folding and misfolding properties of CTF with the processes occurring in the cellular environment. Such models will prove useful towards investigating how changes in the structure of TDP-43 influences its localisation and aggregation under both physiological and cell stress conditions, and how these processes may relate to the pathogenicity and progression of ALS.
39 |Julianna Mohd. Janurudin | University of Oxford
The Fabrication of Superconducting/Polymer Composites for Microwave Applications. The fabrication of metamaterials, in which electromagnetic waves are manipulated by varying the effective permittivity and permeability in three dimensions, is a major area of research worldwide. One approach to producing materials with a controllable spatial distribution of electromagnetic (EM) properties is the synthesis of polymer matrix composites containing different volume fractions of metallic, dielectric or magnetic filler particles. High temperature superconducting (HTS) filler particles can be used to produce temperature-dependent EM properties, with a controlled reduction in permeability as the filler material is cooled into the superconducting state. These composite materials are attractive for variety of potential applications such as active switching and shielding devices for electrical machines, as well as potentially being useful as microwave frequency flux guides for MRI applications. In this study, the basic electromagnetic properties of cast HTS composites have been measured with various volume fractions of YBCO powder, and the permittivity (εr) and permeability (μr) values measured at room and 77K. The EM properties of these HTS composites have been correlated with the homogeneity and density of YBCO particle distributions in the polymer matrix measured using scanning electron microscopy. We show that the εr values of the HTS composite are enhanced with increasing volume fraction of YBCO powder at both room and low temperature. A large drop of μr values with volume fraction is observed at 77K, owing to the diamagnetic response of the superconducting particles. Thus, the refractive index of the composites can be controlled both by volume fraction and temperature. In order to achieve spatial variations in EM properties, we have investigated 3D printing of superconducting composites, a simple and versatile technique for fabricating objects with complex materials properties using polymer-based materials. Our initial experiments have demonstrated that the filament loaded with a chosen volume fraction of YBCO powder can be extruded and we will report initial results on HTS composites fabricated by this technique.
40 |May Ling Lai| University of Cambridge
Bright Light-emitting Diodes based on Organometal Halide Perovskite. Direct bandgap semiconductors have dominated the field of solid-state lighting devices where although it is energy efficient, the high cost of fabrication renders it attractive for usage in large-area displays. Recent progress in organometal-based perovskite materials for high-efficiency photovoltaics demonstrated the suitability for applications in optoelectronic devices. Here, we report high-brightness light-emitting diodes based on solution-processed organometal perovskites. We demonstrate electroluminescence in the near-infrared, green and red by tuning the halide compositions in the perovskite. For the infrared device, CH3NH3PbI3-xClx perovskite emitter is fitted in between larger bandgap titanium dioxide (TiO2) and poly(9,9-dioctyl-fluorene) (F8) layers, confining electrons and holes in the emitter layer for radiative recombination. We report an infrared radiance of 13.2 W sr-1 m-2 at current density of 363 mA cm-2, with the highest external and internal quantum efficiencies of 0.76% and 3.4% respectively. In the green light-emitting device, with CH3NH3PbBr3 perovskite emitter sandwiched between PEDOT:PSS and F8, we achieved a luminance of 364 cd m-2 at a current density of 123 mA cm-2 with external and internal quantum efficiencies of 0.1% and 0.4% respectively. Using the same structure, CH3NH3PbBr2I emitter shows red emission, demonstrating the versatility and tenability of these materials. These findings offer scope for developing this class of materials into efficient and colour-tunable light emitters for low-cost display, lighting and optical communication applications.