19672 research outputs found
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Global Disparities in Breast Cancer Genetics Testing, Counselling and Management
No full textHereditary breast cancers, mainly due to BRCA1 and BRCA2 mutations, account for only 5–10% of this disease. The threshold for genetic testing is a 10% likelihood of detecting a mutation, as determined by validated models such as BOADICEA and Manchester Scoring System. A 90–95% reduction in breast cancer risk can be achieved with bilateral risk-reducing mastectomy in unaffected BRCA mutation carriers. In patients with BRCA-associated breast cancer, there is a 40% risk of contralateral breast cancer and hence risk-reducing contralateral mastectomy is recommended, which can be performed simultaneously with surgery for unilateral breast cancer. Other options for risk management include surveillance by mammogram and breast magnetic resonance imaging, and chemoprevention with hormonal agents. With the advent of next-generation sequencing and development of multigene panel testing, the cost and time taken for genetic testing have reduced, making it possible for treatment-focused genetic testing. There are also drugs such as the PARP inhibitors that specifically target the BRCA mutation. Risk management multidisciplinary clinics are designed to quantify risk, and offer advice on preventative strategies. However, such services are only possible in high-income settings. In low-resource settings, the prohibitive cost of testing and the lack of genetic counsellors are major barriers to setting up a breast cancer genetics service. Family history is often not well documented because of the stigma associated with cancer. Breast cancer genetics services remain an unmet need in low- and middle-income countries, where the priority is to optimise access to quality treatment
Assessment of natural radioactivity in maize and estimation of concomitant dose to nigerian via ingestion pathway
No full textUranium, thorium and potassium are the most abundant naturally occurring radioactive materials (NORMs) found in soils and other environmental media including foodstuffs. Since the human exposures to NORMs is an unavoidable phenomenon, in such a way that they can easily find their way to human being via food chain, detailed knowledge on their presence in foodstuffs is necessary to assess the radiation dose to the population. Thus, the present study concerns the assessment of natural radioactivity in maize, a staple foodstuff for Nigerian, via HPGe gamma-ray spectrometry. Activity concentrations (Bq/kg) in the maize samples were found to be in the range of 6.1 ± 0.6-8.2 ± 1.3, 2.2 ± 0.4-5.1 ± 0.7 and 288 ± 16-401 ± 24 for 226Ra, 232Th and 40K, respectively. Measured data for 226Ra and 232Th show below the world average values of 67 Bq/kg and 82 Bq/kg, respectively, while the activity of 40K exceeds the global average of 310 Bq/kg. The annual effective dose via the maize consumption was found to be far below the UNSCEAR recommended ingestion dose limit of 290 μSv/y, and the estimated lifetime cancer risk show lower than the ICRP (1991) cancer risk factor of 2.5 × 10-3 based on the additional annual dose limit of 1 mSv for general public, thus pose no adverse health risk to the Nigerian populace. © 2019 The Author(s)
Process planning and scheduling for loop layout robotic workcell using virtual reality technology
No full textThe adoption of virtual reality in manufacturing system simulation had proved its effectiveness in bridging up to the gap between different areas of expertise, especially in product design and manufacturing. Virtual reality had enclosed human–machine interface by enabling the user to be immersed into the virtual environment and experience real-time interaction with the virtual objects. In this article, an implementation of virtual reality in cellular manufacturing system simulation is presented. By utilizing the features of visualization and real-time interaction of virtual reality technology, the manufacturing process of a product had been visualized while the real-time control on the product traveling path based on the user’s input was performed and the corresponding activities that related to the change of traveling path had been predicted in the virtual environment. Through the study, simulation of the manufacturing system in virtual reality showed its potential as a powerful decision support system in process planning and scheduling. Various process planning and schedules can be planned through the virtual environment, while the product traveling distance can be obtained from the developed system. © The Author(s) 2019
Design and numerical analysis of interdigitated radiating-strips electrode for uniform 3D dielectrophoretic patterning of liver cells
No full textThis paper presents the design and numerical analysis of a new three-dimensional (3D) electrode having a non-uniform electric field gradient for dielectrophoretic patterning of liver cells. The strength of the dielectrophoresis (DEP) force is influenced by the gradient of electric field generated by the electrode. The new design of the 3D electrode with two different electrode configurations were first modelled and simulated using COMSOL Multiphysics. Results show that the electrical field distribution of vertical configuration concentrated only on the end strips and decays progressively towards the centre while the horizontal configuration shows a more uniform electric field distribution with minimal decrease of the electric field towards the centre. Besides, the horizontal configuration offered 2.7 times higher of the electrical field strength to establish the 3D DEP force hence the 3D cellular pattern. Thus, the electrode with the horizontal configuration has been proposed and optimized to be fabricated for the cell patterning application later on. The optimum electrode dimension identified in this work was 20 µm: 50 µm (gap: height) with a 20 µm electrode width that generates a maximum value of 1.06 × 106 V/m with a voltage set at 5 V. Increasing voltage leads to a stronger electric field and more DEP force would be imposed on the cells. This findings support that the unique design of the 3D electrode can further be used for dielectrophoretic-based patterning mechanism specifically for the complex liver tissue engineering. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature
Description of the female of Simulium (Gomphostilbia) aziruni (Diptera: Simuliidae) and its genetic relationships with members of the Simulium gombakense species-group
No full textSimulium (Gomphostilbia) aziruni Takaoka, Hashim & Chen was described initially based only on a pupa and a mature larva collected from Peninsular Malaysia. Herein, we describe the morphological characters of the female of S. aziruni for the first time. It resembles those of the other members of the Simulium gombakense species-group by the genital fork with a distinct projection directed medioposteriorly from each arm and claw with a large basal tooth. Cytochrome c oxidase I (COI) barcoding analysis indicates that S. aziruni is the sister species of S. maleewongae, but both are distantly separated by a genetic distance of 4.9%. © 2019 Elsevier B.V
Poisson's ratio and volume change accompanying deformation of randomly oriented electrospun nanofibrous membranes
No full textThe present work focuses on the determination of volume change accompanying deformation and Poisson's ratio for electrospun nanofibrous membranes. For this purpose, polyurethane (PU) is considered for the fabrication of electrospun nanofibrous membranes. Three different sample thicknesses are fabricated. Following this, surface morphology analysis and fibre orientation analysis are conducted to investigate the variation of properties between electrospun PU membranes of different thicknesses. Subsequently, PU specimens are subjected to uniaxial extension test where the changes in sample width and thickness are recorded as a function of applied strain. Volume changes are computed while further analysis on the relationship between transverse strains and axial strain provided the values of Poisson's ratio. For all three electrospun PU samples investigated, significant volume changes are observed while the in-plane Poisson's ratio is found to be around 0.55. However, the out-of-plane Poisson's ratio of electrospun PU membranes are not classical and remains undetermined. © 2019, © 2019 Institute of Materials, Minerals and Mining Published by Taylor & Francis on behalf of the Institute
FBG Water-Level Transducer Based on PVC-Cantilever and Rubber-Diaphragm Structure
No full textThe use of FBG sensors in water level monitoring has shown great advantages over the use of conventional electrical sensors. However, much effort is still required to increase their sensitivity towards water level measurement with eliminated sensitivity towards temperature. Here, the FBG was bonded on a PVC polymer plastic cantilever beam and rubber diaphragm structure. The sensing mechanism was based on the differential FBG method. Variations of the water level from 0 to 100 cm obtained the sensitivity of 0.0639 nm/cm with the linearity of 98.06%. The poor linearity was mainly due to the manual fabrication errors. However, this uncertainty can be overcome through the polynomial regression fit in determining the water level measurement. The measured water level was closed to the actual water level at a tolerance of ±2 cm. For temperature effects, the sensitivity was inconspicuous, recorded at only 0.0003 nm/°C across the range of 10 °C to 60 °C. © 2001-2012 IEEE
Current treatment practice of Guillain-Barré syndrome
No full textObjectiveTo define the current treatment practice of Guillain-Barré syndrome (GBS).MethodsThe study was based on prospective observational data from the first 1,300 patients included in the International GBS Outcome Study. We described the treatment practice of GBS in general, and for (1) severe forms (unable to walk independently), (2) no recovery after initial treatment, (3) treatment-related fluctuations, (4) mild forms (able to walk independently), and (5) variant forms including Miller Fisher syndrome, taking patient characteristics and hospital type into account.ResultsWe excluded 88 (7%) patients because of missing data, protocol violation, or alternative diagnosis. Patients from Bangladesh (n = 189, 15%) were described separately because 83% were not treated. IV immunoglobulin (IVIg), plasma exchange (PE), or other immunotherapy was provided in 941 (92%) of the remaining 1,023 patients, including patients with severe GBS (724/743, 97%), mild GBS (126/168, 75%), Miller Fisher syndrome (53/70, 76%), and other variants (33/40, 83%). Of 235 (32%) patients who did not improve after their initial treatment, 82 (35%) received a second immune modulatory treatment. A treatment-related fluctuation was observed in 53 (5%) of 1,023 patients, of whom 36 (68%) were re-treated with IVIg or PE.ConclusionsIn current practice, patients with mild and variant forms of GBS, or with treatment-related fluctuations and treatment failures, are frequently treated, even in absence of trial data to support this choice. The variability in treatment practice can be explained in part by the lack of evidence and guidelines for effective treatment in these situations. © American Academy of Neurology
Ultrasound-Assisted Preparation of Chitosan/Nano-Activated Carbon Composite Beads Aminated with (3-Aminopropyl)Triethoxysilane for Adsorption of Acetaminophen from Aqueous Solutions
No full textA composite chitosan/nano-activated carbon (CS-NAC) aminated by (3-aminopropyl) triethoxysilane (APTES) was prepared in the form of beads and applied for the removal of acetaminophen from aqueous solutions. NAC and APTES concentrations were optimized to obtain a suitable adsorbent structure for enhanced removal of the pharmaceutical. The aminated adsorbent (CS-NAC-APTES beads) prepared with 40% w/w NAC and 2% v/v APTES showed higher adsorption capacity (407.83 mg/g) than CS-NAC beads (278.4 mg/g). Brunauer-Emmett-Teller (BET) analysis demonstrated that the surface area of the CS-NAC-APTES beads was larger than that of CS-NAC beads (1.16 times). The adsorption process was well fitted by the Freundlich model (R2 > 0.95), suggesting a multilayer adsorption. The kinetic study also substantiated that the pseudo-second-order model (R2 > 0.98) was in better agreement with the experimental data. Finally, it was proved that the prepared beads can be recycled (by washing with NaOH solution) at least 5 times before detectable performance loss. © 2019 by the authors
Kcnab1 Is Expressed in Subplate Neurons With Unilateral Long-Range Inter-Areal Projections
No full textSubplate (SP) neurons are among the earliest-born neurons in the cerebral cortex and heterogeneous in terms of gene expression. SP neurons consist mainly of projection neurons, which begin to extend their axons to specific target areas very early during development. However, the relationships between axon projection and gene expression patterns of the SP neurons, and their remnant layer 6b (L6b) neurons, are largely unknown. In this study, we analyzed the corticocortical projections of L6b/SP neurons in the mouse cortex and searched for a marker gene expressed in L6b/SP neurons that have ipsilateral inter-areal projections. Retrograde tracing experiments demonstrated that L6b/SP neurons in the primary somatosensory cortex (S1) projected to the primary motor cortex (M1) within the same cortical hemisphere at postnatal day (PD) 2 but did not show any callosal projection. This unilateral projection pattern persisted into adulthood. Our microarray analysis identified the gene encoding a β subunit of voltage-gated potassium channel (Kcnab1) as being expressed in L6b/SP. Double labeling with retrograde tracing and in situ hybridization demonstrated that Kcnab1 was expressed in the unilaterally-projecting neurons in L6b/SP. Embryonic expression was specifically detected in the SP as early as embryonic day (E) 14.5, shortly after the emergence of SP. Double immunostaining experiments revealed different degrees of co-expression of the protein product Kvβ1 with L6b/SP markers Ctgf (88%), Cplx3 (79%), and Nurr1 (58%), suggesting molecular subdivision of unilaterally-projecting L6b/SP neurons. In addition to expression in L6b/SP, scattered expression of Kcnab1 was observed during postnatal stages without layer specificity. Among splicing variants with three alternative first exons, the variant 1.1 explained all the cortical expression mentioned in this study. Together, our data suggest that L6b/SP neurons have corticocortical projections and Kcnab1 expression defines a subpopulation of L6b/SP neurons with a unilateral inter-areal projection. © 2019 Tiong, Oka, Sasaki, Taniguchi, Doi, Akiyama and Sato