59 research outputs found
A Model for Predicting Magnetic Targeting of Multifunctional Particles in the Microvasculature
A mathematical model is presented for predicting magnetic targeting of
multifunctional carrier particles that are designed to deliver therapeutic
agents to malignant tissue in vivo. These particles consist of a nonmagnetic
core material that contains embedded magnetic nanoparticles and therapeutic
agents such as photodynamic sensitizers. For in vivo therapy, the particles are
injected into the vascular system upstream from malignant tissue, and captured
at the tumor using an applied magnetic field. The applied field couples to the
magnetic nanoparticles inside the carrier particle and produces a force that
attracts the particle to the tumor. In noninvasive therapy the applied field is
produced by a permanent magnet positioned outside the body. In this paper a
mathematical model is developed for predicting noninvasive magnetic targeting
of therapeutic carrier particles in the microvasculature. The model takes into
account the dominant magnetic and fluidic forces on the particles and leads to
an analytical expression for predicting their trajectory. An analytical
expression is also derived for predicting the volume fraction of embedded
magnetic nanoparticles required to ensure capture of the carrier particle at
the tumor. The model enables rapid parametric analysis of magnetic targeting as
a function of key variables including the size of the carrier particle, the
properties and volume fraction of the embedded magnetic nanoparticles, the
properties of the magnet, the microvessel, the hematocrit of the blood and its
flow rate.Comment: To appear in Journal of Magnetism and Magnetic Material
Phylogeographic analysis reveals multiple international transmission events have driven the global emergence of Escherichia coli O157:H7
This work was supported by: Scotland by Food Standards Scotland [Grant Number FS102029] and University of Aberdeen; New Zealand, Institute of Environmental Science and Research; Canada, the Public Health Agency of Canada; United States, United States Department of AgriculturePeer reviewedPostprin
Using sequence data to identify alternative routes and risk of infection: a case-study of campylobacter in Scotland
<b>Background:</b> Genetic typing data are a potentially powerful resource for determining how infection is acquired. In this paper MLST typing was used to distinguish the routes and risks of infection of humans with Campylobacter jejuni from poultry and ruminant sources.<p></p>
<b>Methods:</b> C. jejuni samples from animal and environmental sources and from reported human cases confirmed between June 2005 and September 2006 were typed using MLST. The STRUCTURE software was used to assign the specific sequence types of the sporadic human cases to a particular source. We then used mixed case-case logistic regression analysis to compare the risk factors for being infected with C. jejuni from different sources.<p></p>
<b>Results:</b> A total of 1,599 (46.3%) cases were assigned to poultry, 1,070 (31.0%) to ruminant and 67 (1.9%) to wild bird sources; the remaining 715 (20.7%) did not have a source that could be assigned with a probability of greater than 0.95. Compared to ruminant sources, cases attributed to poultry sources were typically among adults (odds ratio (OR) = 1.497, 95% confidence intervals (CIs) = 1.211, 1.852), not among males (OR = 0.834, 95% CIs = 0.712, 0.977), in areas with population density of greater than 500 people/km(2) (OR = 1.213, 95% CIs = 1.030, 1.431), reported in the winter (OR = 1.272, 95% CIs = 1.067, 1.517) and had undertaken recent overseas travel (OR = 1.618, 95% CIs = 1.056, 2.481). The poultry assigned strains had a similar epidemiology to the unassigned strains, with the exception of a significantly higher likelihood of reporting overseas travel in unassigned strains.<p></p>
<b>Conclusions:</b> Rather than estimate relative risks for acquiring infection, our analyses show that individuals acquire C. jejuni infection from different sources have different associated risk factors. By enhancing our ability to identify at-risk groups and the times at which these groups are likely to be at risk, this work allows public health messages to be targeted more effectively. The rapidly increasing capacity to conduct genetic typing of pathogens makes such traced epidemiological analysis more accessible and has the potential to substantially enhance epidemiological risk factor studies
Synapse loss in the prefrontal cortex is associated with cognitive decline in amyotrophic lateral sclerosis
Climate, human behaviour or environment: individual-based modelling of Campylobacter seasonality and strategies to reduce disease burden
Acknowledgements: We thank colleagues within the Modelling, Evidence and Policy Research Group for useful feedback on this manuscript. Competing interests: The authors declare that they have no competing interests. Availability of data and materials: The R code used in this research is available at https://gitlab.com/rasanderson/campylobacter-microsimulation; it is platform independent, R version 3.3.0 and above. Funding: This research was funded by Medical Research Council Grant, Natural Environment Research Council, Economic and Social Research Council, Biotechnology and Biological Sciences Research Council, and the Food Standards Agency through the Environmental and Social Ecology of Human Infectious Diseases Initiative (Sources, seasonality, transmission and control: Campylobacter and human behaviour in a changing environment (ENIGMA); Grant Reference G1100799-1). PRH, SJOâB, and IRL are funded in part by the NIHR Health Protection Research Unit in Gastrointestinal Infection, at the University of Liverpool. PRH and IRL are also funded in part by the NIHR Health Protection Research Unit in Emergency Preparedness and Response, at Kingâs College London. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, the Department of Health or Public Health England.Peer reviewedPublisher PD
Prevalence, quantitative load and genetic diversity of Campylobacter spp. in dairy cattle herds in Lithuania
C6 Are there any factors predicting the postoperative complications of transurethral resection of the prostate?
C108 ADJUVANT INSTILLATION THERAPY IN THE TREATMENT OF NON-MUSCLE INVASIVE BLADDER CANCER DURING THE FIRST TWO YEARS AFTER TRANSURETHRAL RESECTION
Characteristics and outcome of surgically treated acromegaly patients attending an endocrinology clinic at a tertiary referral centre in Durban, South Africa over a period of 10Â years
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