4 research outputs found
High performance graph analysis on parallel architectures
PhD ThesisOver the last decade pharmacology has been developing computational
methods to enhance drug development and testing. A computational
method called network pharmacology uses graph analysis
tools to determine protein target sets that can lead on better targeted
drugs for diseases as Cancer. One promising area of network-based
pharmacology is the detection of protein groups that can produce
better e ects if they are targeted together by drugs. However, the
e cient prediction of such protein combinations is still a bottleneck
in the area of computational biology.
The computational burden of the algorithms used by such protein
prediction strategies to characterise the importance of such proteins
consists an additional challenge for the eld of network pharmacology.
Such computationally expensive graph algorithms as the all pairs
shortest path (APSP) computation can a ect the overall drug discovery
process as needed network analysis results cannot be given on
time. An ideal solution for these highly intensive computations could
be the use of super-computing. However, graph algorithms have datadriven
computation dictated by the structure of the graph and this
can lead to low compute capacity utilisation with execution times
dominated by memory latency.
Therefore, this thesis seeks optimised solutions for the real-world
graph problems of critical node detection and e ectiveness characterisation
emerged from the collaboration with a pioneer company in the
eld of network pharmacology as part of a Knowledge Transfer Partnership
(KTP) / Secondment (KTS). In particular, we examine how
genetic algorithms could bene t the prediction of protein complexes
where their removal could produce a more e ective 'druggable' impact.
Furthermore, we investigate how the problem of all pairs shortest
path (APSP) computation can be bene ted by the use of emerging
parallel hardware architectures as GPU- and FPGA- desktop-based
accelerators.
In particular, we address the problem of critical node detection with
the development of a heuristic search method. It is based on a genetic
algorithm that computes optimised node combinations where their removal
causes greater impact than common impact analysis strategies.
Furthermore, we design a general pattern for parallel network analysis
on multi-core architectures that considers graph's embedded properties.
It is a divide and conquer approach that decomposes a graph
into smaller subgraphs based on its strongly connected components
and computes the all pairs shortest paths concurrently on GPU. Furthermore,
we use linear algebra to design an APSP approach based
on the BFS algorithm. We use algebraic expressions to transform the
problem of path computation to multiple independent matrix-vector
multiplications that are executed concurrently on FPGA. Finally, we
analyse how the optimised solutions of perturbation analysis and parallel
graph processing provided in this thesis will impact the drug
discovery process.This research was part of a Knowledge Transfer Partnership (KTP)
and Knowledge Transfer Secondment (KTS) between e-therapeutics
PLC and Newcastle University. It was supported as a collaborative
project by e-therapeutics PLC and Technology Strategy boar
Outdoor particulate matter and childhood asthma admissions in Athens, Greece: a time-series study
<p>Abstract</p> <p>Background</p> <p>Particulate matter with diameter less than 10 micrometers (PM<sub>10</sub>) that originates from anthropogenic activities and natural sources may settle in the bronchi and cause adverse effects possibly via oxidative stress in susceptible individuals, such as asthmatic children. This study aimed to investigate the effect of outdoor PM<sub>10 </sub>concentrations on childhood asthma admissions (CAA) in Athens, Greece.</p> <p>Methods</p> <p>Daily counts of CAA from the three Children's Hospitals within the greater Athens' area were obtained from the hospital records during a four-year period (2001-2004, n = 3602 children). Mean daily PM<sub>10 </sub>concentrations recorded by the air pollution-monitoring network of the greater Athens area were also collected. The relationship between CAA and PM<sub>10 </sub>concentrations was investigated using the Generalized Linear Models with Poisson distribution and logistic analysis.</p> <p>Results</p> <p>There was a statistically significant (95% CL) relationship between CAA and mean daily PM<sub>10 </sub>concentrations on the day of exposure (+3.8% for 10 μg/m<sup>3 </sup>increase in PM<sub>10 </sub>concentrations), while a 1-day lag (+3.4% for 10 μg/m<sup>3 </sup>increase in PM<sub>10 </sub>concentrations) and a 4-day lag (+4.3% for 10 μg/m<sup>3 </sup>increase in PM<sub>10 </sub>concentrations) were observed for older asthmatic children (5-14 year-old). High mean daily PM<sub>10 </sub>concentration (the highest 10%; >65.69 μg/m<sup>3</sup>) doubled the risk of asthma exacerbations even in younger asthmatic children (0-4 year-old).</p> <p>Conclusions</p> <p>Our results provide evidence of the adverse effect of PM<sub>10 </sub>on the rates of paediatric asthma exacerbations and hospital admissions. A four-day lag effect between PM<sub>10 </sub>peak exposure and asthma admissions was also observed in the older age group.</p
External validation and recalibration of an incidental meningioma prognostic model - IMPACT: protocol for an international multicentre retrospective cohort study
Introduction: Due to the increased use of CT and MRI, the prevalence of incidental findings on brain scans is increasing. Meningioma, the most common primary brain tumour, is a frequently encountered incidental finding, with an estimated prevalence of 3/1000. The management of incidental meningioma varies widely with active clinical-radiological monitoring being the most accepted method by clinicians. Duration of monitoring and time intervals for assessment, however, are not well defined. To this end, we have recently developed a statistical model of progression risk based on single-centre retrospective data. The model Incidental Meningioma: Prognostic Analysis Using Patient Comorbidity and MRI Tests (IMPACT) employs baseline clinical and imaging features to categorise the patient with an incidental meningioma into one of three risk groups: low, medium and high risk with a proposed active monitoring strategy based on the risk and temporal trajectory of progression, accounting for actuarial life expectancy. The primary aim of this study is to assess the external validity of this model. Methods and analysis: IMPACT is a retrospective multicentre study which will aim to include 1500 patients with an incidental intracranial meningioma, powered to detect a 10% progression risk. Adult patients ≥16 years diagnosed with an incidental meningioma between 1 January 2009 and 31 December 2010 will be included. Clinical and radiological data will be collected longitudinally until the patient reaches one of the study endpoints: intervention (surgery, stereotactic radiosurgery or fractionated radiotherapy), mortality or last date of follow-up. Data will be uploaded to an online Research Electronic Data Capture database with no unique identifiers. External validity of IMPACT will be tested using established statistical methods. Ethics and dissemination: Local institutional approval at each participating centre will be required. Results of the study will be reported through peer-reviewed articles and conferences and disseminated to participating centres, patients and the public using social media