272 research outputs found
Effect of substrate thermal resistance on space-domain microchannel
In recent years, Fluorescent Melting Curve Analysis (FMCA) has become an almost ubiquitous feature of commercial quantitative PCR (qPCR) thermal cyclers. Here a micro-fluidic device is presented capable of performing FMCA within a microchannel. The device consists of modular thermally conductive blocks which can sandwich a microfluidic substrate. Opposing ends of the blocks are held at differing temperatures and a linear thermal gradient is generated along the microfluidic channel. Fluorescent measurements taken from a sample as it passes along the micro-fluidic channel permits fluorescent melting curves to be generated. In this study we measure DNA melting temperature from two plasmid fragments. The effects of flow velocity and ramp-rate are investigated, and measured melting curves are compared to those acquired from a commercially available PCR thermocycler
Development of an opportunistic diagnostic prediction algorithm for osteoporosis and fragility fracture risk estimates from forearm radiographs (The OFFER1 Study)
This is a preprintData availability statement: The data that support the findings of this study are available from the corresponding author upon reasonable request.Osteoporosis and associated fractures are an increasingly prevalent concern in context with an ageing population. This study reports testing of IBEX Bone Health (IBEX BH) software, applied following acquisition of forearm radiographs. IBEX BH analyses the radiograph to measure areal bone mineral density (aBMD) at the examination site.
A non-randomised cross-sectional study design was performed involving 261 (254 after exclusions) participants (112/142 m/f; mean age 70.8years (SD+/-9.0); 53 with osteoporosis). They underwent posterior-anterior distal forearm radiographs; dual x-ray absorptiometry (DXA) of the wrists, hips and lumbar spine; and, questionnaires exploring clinical risk factors.
IBEX BH automatically identifies regions of interest (ROI) at the ultra-distal (UD) and distal third (TD) regions of the radius. Analysis investigated the area under the receiver operating characteristics curve (AUC) performance of IBEX BH for prediction of i) osteoporosis (based on clinical reporting of the hip and spine DXA) and ii) treatment recommendations by Fracture Risk Assessment Tool (FRAX) inclusive of neck of femur (NoF) areal bone mineral density (aBMD) results following National Osteoporosis Guideline Group (NOGG) guidelines.
AUC for osteoporosis prediction at the UD and TD ROIs were 0.86 (99% Confidence interval (CI) [0.80, 0.91]) and 0.81 (99% CI [0.75, 0.88]), respectively. AUC for treatment recommendation using FRAX inclusive of NoF aBMD at the UD and TD ROIs were 0.95 (99% CI [0.91, 1.00]) and 0.97 (99% CI [0.93,1.00]), respectively. With a matched sensitivity to FRAX (without NoF aBMD) 0.93 (99% CI [0.78, 0.99]), IBEX BH predicted at the UD and TD ROIs recommended treatment outcomes by NOGG guidelines using FRAX (with NoF aBMD) with specificity 0.89 (99% CI 0.83, 0.94]) and 0.93 (99% CI [0.87, 0.97]), respectively. This is compared with 0.60 (99% CI [0.51, 0.69]) for FRAX (without NoF aBMD). Results demonstrate the potential clinical utility of IBEX BH as an opportunistic screening tool.Ibex Innovation
The biomechanics of metaphyseal cone augmentation in revision knee replacement
This is the final version. Available on open access from Elsevier via the DOI in this recordThe demand for revision knee replacement (RKR) has increased dramatically with rising patient life expectancy and younger recipients for primary TKR. However, significant challenges to RKR arise from osseous defects, reduced bone quality, potential bone volume loss from implant removal and the need to achieve implant stability. This study utilizes the outcomes of an ongoing RKR clinical trial using porous metaphyseal cones 3D-printed of titanium, to investigate 1) bone mineral density (BMD) changes in three fixation zones (epiphysis, metaphysis, and diaphysis) over a year and 2) the biomechanical effects of the cones at 6 months post-surgery. It combines dual-energy x-ray absorptiometry (DXA), computed tomography (CT) with patient-specific based finite element (FE) modelling. Bone loss (-0.086 ± 0.05 g/cm2) was found in most patients over the first year. The biomechanical assessment considered four different loading scenarios from standing, walking on a flat surface, and walking downstairs, to a simulated impact of the knee. The patient-specific FE models showed that the cones marginally improved the strain distribution in the bone and shared the induced load but played a limited role in reducing the risks of bone fracture or cement debonding. This technique of obtaining real live data from a randomized clinical trial and inserting it into an in-silico FE model is unique and innovative in RKR research. The tibia RKR biomechanics examined open up further possibilities, allowing the in-silico testing of prototypes and implant combinations without putting patients at risk as per the recommended IDEAL framework standards. This process with further improvements could allow rapid innovation, optimization of implant design, and improve surgical planning.Engineering and Physical Sciences Research Council (EPSRC
How to Educate Entrepreneurs?
Entrepreneurship education has two purposes: To improve students’ entrepreneurial skills and to provide impetus to those suited to entrepreneurship while discouraging the rest. While entrepreneurship education helps students to make a vocational decision its effects may conflict for those not suited to entrepreneurship. This study shows that vocational and the skill formation effects of entrepreneurship education can be identified empirically by drawing on the Theory of Planned Behavior. This is embedded in a structural equation model which we estimate and test using a robust 2SLS estimator. We find that the attitudinal factors posited by the Theory of Planned Behavior are positively correlated with students’ entrepreneurial intentions. While conflicting effects of vocational and skill directed course content are observed in some individuals, overall these types of content are complements. This finding contradicts previous results in the literature. We reconcile the conflicting findings and discuss implications for the design of entrepreneurship courses
The effectiveness of public health interventions to reduce the health impact of climate change:a systematic review of systematic reviews
Climate change is likely to be one of the most important threats to public health in the coming years. Yet despite the large number of papers considering the health impact of climate change, few have considered what public health interventions may be of most value in reducing the disease burden. We aimed to evaluate the effectiveness of public health interventions to reduce the disease burden of high priority climate sensitive diseases
Small firms and patenting revisited
In order to observe a patent application at the firm level two conditions need to be met: new products need to be of patentable quality, which depends both on the degree of novelty of innovations and on the total number (portfolio) of innovations; and the benefits of patents
need to be higher than the costs of owning them. Analyzing the patent propensity of small and large UK firms using a novel innovation-level survey (the SIPU survey) linked to Community Innovation Survey data we find that when we consider the whole innovation portfolio smaller firms do patent less than larger firms. However, using data on individual
innovations, we find that smaller firms are no less likely to patent any specific innovation than larger firms. We argue that size differences in the probability to patent relate primarily to the ‘portfolio effect’, i.e. larger firms generate more innovations than smaller firms and therefore are more likely to create one or more which are patentable. As for the decision to patent a patentable innovation, we find that cost barriers, more than issues of innovation quality or enforceability, deter small firms from patenting specific innovations. Measures to address the costs of patenting for smaller firms – perhaps by considering patents as eligible
costs for R&D tax credits – and/or subsidizing SMEs’ participation in IP litigation schemes may both encourage patent use by smaller firms
ngs_backbone: a pipeline for read cleaning, mapping and SNP calling using Next Generation Sequence
Background: The possibilities offered by next generation sequencing (NGS) platforms are revolutionizing
biotechnological laboratories. Moreover, the combination of NGS sequencing and affordable high-throughput
genotyping technologies is facilitating the rapid discovery and use of SNPs in non-model species. However, this
abundance of sequences and polymorphisms creates new software needs. To fulfill these needs, we have
developed a powerful, yet easy-to-use application.
Results: The ngs_backbone software is a parallel pipeline capable of analyzing Sanger, 454, Illumina and SOLiD
(Sequencing by Oligonucleotide Ligation and Detection) sequence reads. Its main supported analyses are: read
cleaning, transcriptome assembly and annotation, read mapping and single nucleotide polymorphism (SNP) calling
and selection. In order to build a truly useful tool, the software development was paired with a laboratory
experiment. All public tomato Sanger EST reads plus 14.2 million Illumina reads were employed to test the tool
and predict polymorphism in tomato. The cleaned reads were mapped to the SGN tomato transcriptome
obtaining a coverage of 4.2 for Sanger and 8.5 for Illumina. 23,360 single nucleotide variations (SNVs) were
predicted. A total of 76 SNVs were experimentally validated, and 85% were found to be real.
Conclusions: ngs_backbone is a new software package capable of analyzing sequences produced by NGS
technologies and predicting SNVs with great accuracy. In our tomato example, we created a highly polymorphic
collection of SNVs that will be a useful resource for tomato researchers and breeders. The software developed
along with its documentation is freely available under the AGPL license and can be downloaded from http://bioinf.
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A Systematic Analysis of Eluted Fraction of Plasma Post Immunoaffinity Depletion: Implications in Biomarker Discovery
Plasma is the most easily accessible source for biomarker discovery in clinical proteomics. However, identifying potential biomarkers from plasma is a challenge given the large dynamic range of proteins. The potential biomarkers in plasma are generally present at very low abundance levels and hence identification of these low abundance proteins necessitates the depletion of highly abundant proteins. Sample pre-fractionation using immuno-depletion of high abundance proteins using multi-affinity removal system (MARS) has been a popular method to deplete multiple high abundance proteins. However, depletion of these abundant proteins can result in concomitant removal of low abundant proteins. Although there are some reports suggesting the removal of non-targeted proteins, the predominant view is that number of such proteins is small. In this study, we identified proteins that are removed along with the targeted high abundant proteins. Three plasma samples were depleted using each of the three MARS (Hu-6, Hu-14 and Proteoprep 20) cartridges. The affinity bound fractions were subjected to gelC-MS using an LTQ-Orbitrap instrument. Using four database search algorithms including MassWiz (developed in house), we selected the peptides identified at <1% FDR. Peptides identified by at least two algorithms were selected for protein identification. After this rigorous bioinformatics analysis, we identified 101 proteins with high confidence. Thus, we believe that for biomarker discovery and proper quantitation of proteins, it might be better to study both bound and depleted fractions from any MARS depleted plasma sample
Is detection of intraperitoneal exfoliated tumor cells after surgical resection of rectal cancer a prognostic factor of survival?
Proteomic Analysis of Polypeptides Captured from Blood during Extracorporeal Albumin Dialysis in Patients with Cholestasis and Resistant Pruritus
Albumin dialysis using the molecular adsorbent recirculating system (MARS) is a new therapeutic approach for liver diseases. To gain insight into the mechanisms involved in albumin dialysis, we analyzed the peptides and proteins absorbed into the MARS strong anion exchange (SAX) cartridges as a result of the treatment of patients with cholestasis and resistant pruritus. Proteins extracted from the SAX MARS cartridges after patient treatment were digested with two enzymes. The resulting peptides were analyzed by multidimensional liquid chromatography coupled to tandem mass spectrometry. We identified over 1,500 peptide sequences corresponding to 144 proteins. In addition to the proteins that are present in control albumin-derived samples, this collection includes 60 proteins that were specific to samples obtained after patient treatment. Five of these proteins (neutrophil defensin 1 [HNP-1], secreted Ly-6/uPAR-related protein 1 [SLURP1], serum amyloid A, fibrinogen alpha chain and pancreatic prohormone) were confirmed to be removed by the dialysis procedure using targeted selected-reaction monitoring MS/MS. Furthermore, capture of HNP-1 and SLURP1 was also validated by Western blot. Interestingly, further analyses of SLURP1 in serum indicated that this protein was 3-fold higher in cholestatic patients than in controls. Proteins captured by MARS share certain structural and biological characteristics, and some of them have important biological functions. Therefore, their removal could be related either to therapeutic or possible adverse effects associated with albumin dialysis
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