Characterisation of the functional consequences of PTEN gene mutation on colon cancer

University of Technology, Sydney. Faculty of Science.olon cancer constitutes the second most common cause of cancer death in many Western countries. The PTEN tumour suppressor gene, located on chromosome 10q23.3, is now recognised as the most highly mutated tumour suppressor gene. PTEN, a lipid and protein phosphatase, regulates the phosphatidylinositol 3-kinase (PI3K)/ Akt signalling pathway and modulates cell cycle progression and cell survival. Previous work at University of Technology of Sydney laboratory has shown that a significant proportion of sporadic colorectal tumours harbour PTEN mutations that alter gene function and may therefore contribute to the pathways of colorectal carcinogenesis. A total of 10 novel somatic mutations have been described. In order to determine the functional consequences of these colon cancer-associated PTEN mutations, the wild type (WT) PTEN gene was cloned into a mammalian expression vector system and each of the mutants were generated from this. The WT, and each of the mutant K62R, Y65C, K125E, K125X, E150Q, D153N, D153Y, V217A 319X and N323K PTEN constructs were then transiently transfected into an U87MG glioblastoma PTEN null cell line and HCT116 colon cancer PTEN expressing cell lines that were then assayed for cell cycle phase distribution, Akt phosphorylation levels and cell proliferation. The analyses of endogenous suppression of Phospho Akt assay indicates 50% of PTEN mutants (Y65C, K125E, K125X, D153N, and 319 X) shows deficiency in the U87MG cell line and 70% of the mutants in the EICT116 cell line (Y65C, K125E, K125X, D153N, D153\ V217A and 319X) had deficiency in suppressing endogenous phosphorylated Akt. The results obtained show 50% (Y65C, K125X, K125E, D153N and 319X) of the PTEN mutants had functional deficiency in cell cycle inhibitory capacity in the S phase in the U87MG cells; in contrast 80% (Y65C, K125X, K125E, E150Q, D153N, D153Y, V217A and 319X) of the PTEN mutants had functional deficiency in cell cycle inhibitory capacity in the S phase in the HCT116 cells. The results obtained show 60% of the PTEN mutants (K62R, Y65C, K125E, K125X, D153N and 319X) had alteration in cell proliferation rate in U87MG cells. In contrast in the HCT116 cell lines, 80% of the PTEN mutants (Y65C, K125E, K125X, E150Q, D153N, D153Y, V217A and 319X) had alteration in cell proliferation rates. These three functional assays of the mutations tested show an alteration of PTEN function. This was observed as a marked reduction in the ability of these PTEN mutants to bring about a level of cycle arrest, reduction of Akt phosphorylation levels and cell proliferation, compared to that observed with the WT PTEN gene product. These studies reveal that PTEN gene somatic mutations do alter PTEN function and are therefore likely to contribute to the process of colorectal carcinogenesis and may mediate a PTEN- associated carcinogenic pathway in these tumours

Modeling and control of TCV

Published versio

Integrating 3D Printing Technology into Arts, Science, and Engineering Subjects

Abstract A strong emphasis on active learning and integration of hands-on activities into course curriculum have been shown to significantly enhance students\u27 conceptual understanding of the course. Three-dimensional (3D) printing, also called additive manufacturing, has been a subject of many academic and industrial research projects. Many higher education institutions across the United States and the world are increasingly incorporating 3D printing technology into their curriculum. 3D printing is a manufacturing method in which solid 3D objects are printed layer by layer from raw materials. Various types of raw materials can be used for 3D printing that include plastics, metal, nylon, ceramic, powders, and liquids. Currently, plastics are the most widely used materials. The Art Department in collaboration with the Physics Department at the University of North Georgia (UNG) Gainesville opened the 3D Printing Lab, focused on producing physical models from computer-designed, virtual models. The goals are to assist faculty in using 3D printing technology and to develop the curriculum. The UNG 3D Printing Lab, located in Dunlap Mathis Building, provides students and faculty with state-of-the-art lab and collaborative project spaces. The lab is currently equipped with a variety of 3D printers, 3D digital scanners, and slicing software for 3D printers. Currently, students from Art, Physics, and Pre-engineering programs are able to develop and print models individually designed for class projects, design groups, research, or personal use. The Art and Physics departments operate the lab with student supervisors from the two departments, who are available to assist in printing models. Keywords: 3D printing, 3D digital scanners, and plastic

#32 - Incorporating 3D Printing into Introductory Engineering Courses

Integration of hands-on activities, and design projects into course curriculum have been shown to significantly enhance and deepen understanding of concepts in the course. Three-dimensional (3D) printing has been a subject of many academic and industrial research projects. This abstract presents our efforts to integrate 3D printing technology into our pre-engineering and physics courses at University of North Georgia (UNG) Gainesville campus. The Physics Department in collaboration with the Art Department in the UNG Gainesville Campus opened a Digital Fabrication Lab (DFL) located in Dunlap Mathis Building. The goals of the lab are to assist faculty to develop the curriculum and to help students develop a deeper understanding of science and engineering techniques when creating a digital 3D object. A formal introduction to the DFL’s 3D printers is presented as a part of Computer-Aided Design (CAD) topics in the pre-engineering courses. As part of a semester group project, student project teams created CAD models of their design using Autodesk’s CAD software and 3D printed them with the assistance of the TAs. Most of the students who took part in this design projects had no or limited experience with both CAD modeling as well as 3D printing technology. But despite having limited prior experience, all student indicated a relatively high interest in learning more about 3D printing technology. Currently Physics, Pre-engineering, and Art students have been direct beneficiaries of the Digital Fabrication Lab. 3D printing technology helped students to successfully correlate and implement various science and engineering concepts that they learnt in class through hands-on activities. In the future, research will go into finding out ways 3D printing can be introduced to higher level science and engineering classes, by showcasing 3D printed objects and different filaments’ properties, such as tolerances, tensile strength, elastic strength etc

Cardiac imaging to detect coronary artery disease in athletes aged 35 years and older. A scoping review.

Sudden cardiac death (SCD) is a devastating event in athletes. Screening efforts that were first directed at athletes younger than 35 years, are now focusing on the rapidly growing group of older sportspersons. Athletes aged ≥35 years have a 10-fold increased risk of exercise-related cardiac arrest, mostly due to coronary artery disease (CAD). Although cardiac imaging is pivotal in identifying CAD, the role of imaging modalities in screening asymptomatic older sportspersons remains unclear. We performed a scoping review to identify the role of cardiac imaging to detect CAD in older sportspersons and to identify gaps in the existing literature. We searched Medline, Embase and the Cochrane library for studies reporting data on cardiac imaging of CAD in sportspersons ≥35 years. The systematic search yielded 1737 articles and 14 were included in this scoping review. Imaging modalities included 2 echocardiography, 1 unenhanced Computed Tomography (CT) for coronary artery calcium scoring (CACS), 3 CACS and contrast-enhanced CT angiography (CCTA), 2 CACS and Cardiac Magnetic Resonance (CMR), 1 CCTA with CMR and echocardiography, 2 CCTA, 2 CMR, and 1 myocardial perfusion imaging article. The low number of relevant articles and the selection bias introduced by studying specific groups, like veteran marathon runners, indicate the need for future research. Cardiac CT (CACS and CCTA) probably has the highest potential for pre-participation screening, with high diagnostic value to detect CAD and low radiation dose. However, currently there is insufficient evidence for incorporating routine cardiac imaging in the pre-participation screening of asymptomatic sportspersons over 35 years

Refractive change following pseudophakic vitrectomy: a retrospective review

Background To assess the occurrence and magnitude of refractive change in pseudophakic eyes undergoing 20 gauge pars plana vitrectomy without scleral buckling and to investigate possible aetiological factors. Methods Retrospective case note review of 87 pseudophakic eyes undergoing 20 gauge pars plana vitrectomy for a variety of vitreo-retinal conditions over a three-year period. Anterior chamber depth (ACD) was measured before and after vitrectomy surgery in 32 eyes. Forty-three pseudophakic fellow eyes were used as controls. Results Eighty-seven eyes (84 patients) were included in the study. Mean spherical equivalent refraction prior to vitrectomy was -0.20 dioptres, which changed to a mean of -0.65 dioptres postoperatively (standard deviation of refractive change 0.59, range-2.13 to 0.75 dioptres) (p < 0.001). Sixty-one of the 87(70%) eyes experienced a myopic shift and 45(52%) eyes had a myopic shift of -0.5 dioptres or more. Mean fellow eye refraction was -0.19 dioptres preoperatively and -0.17 dioptres postoperatively (p = 0.14)(n = 37) Mean ACD preoperatively was 3.29 mm and postoperatively 3.27 mm (p = 0.53) (n = 32) and there was no significant change in ACD with tamponade use. Regression analysis revealed no statistically significant association between changes in anterior chamber depth, as well as a wide variety of other pre-, intra and postoperative factors examined, and the refractive change observed. Conclusion Significant refractive changes occur in some pseudophakic patients undergoing 20 g pars plana vitrectomy. The mean change observed was a small myopic shift but the range was large. The aetiology of the refractive change is uncertain

The structure of a resuscitation-promoting factor domain from Mycobacterium tuberculosis shows homology to lysozymes

Resuscitation-promoting factor (RPF) proteins reactivate stationary-phase cultures of (G+C)-rich Gram-positive bacteria including the causative agent of tuberculosis, Mycobacterium tuberculosis. We report the solution structure of the RPF domain from M. tuberculosis Rv1009 (RpfB) solved by heteronuclear multidimensional NMR. Structural homology with various glycoside hydrolases suggested that RpfB cleaved oligosaccharides. Biochemical studies indicate that a conserved active site glutamate is important for resuscitation activity. These data, as well as the presence of a clear binding pocket for a large molecule, indicate that oligosaccharide cleavage is probably the signal for revival from dormancy

Metamaterial Applicator for Hyperthermia Cancer Treatment Procedure: Overview Study

This paper presents an overview of metamaterial slabs or lens as an integrated structure for applicators used in hyperthermia cancer treatment procedure. Hyperthermia treatment procedure (HTP) is a new technique that exposes a cancerous tissue by increasing tissue temperature until 41 °C to 45 °C at a certain period with electromagnetic radiation. Based on the previous study, by moving the microwave sources relative to the metamaterial (MTM) lenses from a tumor/cancer phantom alters the concentration of heating within biological tissue. In this paper, the overview of a metamaterial study on HTP from 2009 to 2019 was carried out. This study indicated that the left-handed metamaterial (LHM) lens was observed to be able to improve the focusing capabilities of HTP on the treated tissue. However, a further study is significantly required to provide different focus position distances on the treated tissue for different stages of cancer. Therefore, a modified HTP applicator integration with an MTM lens structure was proposed. It is aimed to improve focus position distance on the treated tissue and to reduce unwanted hot-spots on surrounding healthy tissues simultaneously. The proposed modified structure was presented in this paper. Specific absorption rate (SAR) simulation was carried out with SEMCAD X 14.8.4 to obtain a SAR distribution for determining penetration depth and focusing position distance on the treated tissu

DNA-based Self-Assembly of Chiral Plasmonic Nanostructures with Tailored Optical Response

Surface plasmon resonances generated in metallic nanostructures can be utilized to tailor electromagnetic fields. The precise spatial arrangement of such structures can result in surprising optical properties that are not found in any naturally occurring material. Here, the designed activity emerges from collective effects of singular components equipped with limited individual functionality. Top-down fabrication of plasmonic materials with a predesigned optical response in the visible range by conventional lithographic methods has remained challenging due to their limited resolution, the complexity of scaling, and the difficulty to extend these techniques to three-dimensional architectures. Molecular self-assembly provides an alternative route to create such materials which is not bound by the above limitations. We demonstrate how the DNA origami method can be used to produce plasmonic materials with a tailored optical response at visible wavelengths. Harnessing the assembly power of 3D DNA origami, we arranged metal nanoparticles with a spatial accuracy of 2 nm into nanoscale helices. The helical structures assemble in solution in a massively parallel fashion and with near quantitative yields. As a designed optical response, we generated giant circular dichroism and optical rotary dispersion in the visible range that originates from the collective plasmon-plasmon interactions within the nanohelices. We also show that the optical response can be tuned through the visible spectrum by changing the composition of the metal nanoparticles. The observed effects are independent of the direction of the incident light and can be switched by design between left- and right-handed orientation. Our work demonstrates the production of complex bulk materials from precisely designed nanoscopic assemblies and highlights the potential of DNA self-assembly for the fabrication of plasmonic nanostructures.Comment: 5 pages, 4 figure

Classification of patients with knee osteoarthritis in clinical phenotypes: data from the osteoarthritis initiative

<div><p>Objectives</p><p>The existence of phenotypes has been hypothesized to explain the large heterogeneity characterizing the knee osteoarthritis. In a previous systematic review of the literature, six main phenotypes were identified: Minimal Joint Disease (MJD), Malaligned Biomechanical (MB), Chronic Pain (CP), Inflammatory (I), Metabolic Syndrome (MS) and Bone and Cartilage Metabolism (BCM). The purpose of this study was to classify a sample of individuals with knee osteoarthritis (KOA) into pre-defined groups characterized by specific variables that can be linked to different disease mechanisms, and compare these phenotypes for demographic and health outcomes.</p><p>Methods</p><p>599 patients were selected from the OAI database FNIH at 24 months’ time to conduct the study. For each phenotype, cut offs of key variables were identified matching the results from previous studies in the field and the data available for the sample. The selection process consisted of 3 steps. At the end of each step, the subjects classified were excluded from the further classification stages. Patients meeting the criteria for more than one phenotype were classified separately into a ‘complex KOA’ group.</p><p>Results</p><p>Phenotype allocation (including complex KOA) was successful for 84% of cases with an overlap of 20%. Disease duration was shorter in the MJD while the CP phenotype included a larger number of Women (81%). A significant effect of phenotypes on WOMAC pain (F = 16.736 p <0.001) and WOMAC physical function (F = 14.676, p < 0.001) was identified after controlling for disease duration.</p><p>Conclusion</p><p>This study signifies the feasibility of a classification of KOA subjects in distinct phenotypes based on subgroup-specific characteristics.</p></div