2,052 research outputs found
Resource use data by patient report or hospital records: Do they agree?
Background: Economic evaluations alongside clinical trials are becoming increasingly common.
Cost data are often collected through the use of postal questionnaires; however, the accuracy of
this method is uncertain. We compared postal questionnaires with hospital records for collecting
data on physiotherapy service use.
Methods: As part of a randomised trial of orthopaedic medicine compared with orthopaedic
surgery we collected physiotherapy use data on a group of patients from retrospective postal
questionnaires and from hospital records.
Results: 315 patients were referred for physiotherapy. Hospital data on attendances was available
for 30% (n = 96), compared with 48% (n = 150) of patients completing questionnaire data (95% Cl
for difference = 10% to 24%); 19% (n = 59) had data available from both sources. The two methods
produced an intraclass correlation coefficient of 0.54 (95% Cl 0.31 to 0.70). However, the two
methods produced significantly different estimates of resource use with patient self report recalling
a mean of 1.3 extra visits (95% Cl 0.4 to 2.2) compared with hospital records.
Conclusions: Using questionnaires in this study produced data on a greater number of patients
compared with examination of hospital records. However, the two data sources did differ in the
quantity of physiotherapy used and this should be taken into account in any analysi
Using Seroprevalence and Immunisation Coverage Data to Estimate the Global Burden of Congenital Rubella Syndrome, 1996-2010: A Systematic Review.
BACKGROUND: The burden of Congenital Rubella Syndrome (CRS) is typically underestimated in routine surveillance. Updated estimates are needed following the recent WHO position paper on rubella and recent GAVI initiatives, funding rubella vaccination in eligible countries. Previous estimates considered the year 1996 and only 78 (developing) countries. METHODS: We reviewed the literature to identify rubella seroprevalence studies conducted before countries introduced rubella-containing vaccination (RCV). These data and the estimated vaccination coverage in the routine schedule and mass campaigns were incorporated in mathematical models to estimate the CRS incidence in 1996 and 2000-2010 for each country, region and globally. RESULTS: The estimated CRS decreased in the three regions (Americas, Europe and Eastern Mediterranean) which had introduced widespread RCV by 2010, reaching <2 per 100,000 live births (the Americas and Europe) and 25 (95% CI 4-61) per 100,000 live births (the Eastern Mediterranean). The estimated incidence in 2010 ranged from 90 (95% CI: 46-195) in the Western Pacific, excluding China, to 116 (95% CI: 56-235) and 121 (95% CI: 31-238) per 100,000 live births in Africa and SE Asia respectively. Highest numbers of cases were predicted in Africa (39,000, 95% CI: 18,000-80,000) and SE Asia (49,000, 95% CI: 11,000-97,000). In 2010, 105,000 (95% CI: 54,000-158,000) CRS cases were estimated globally, compared to 119,000 (95% CI: 72,000-169,000) in 1996. CONCLUSIONS: Whilst falling dramatically in the Americas, Europe and the Eastern Mediterranean after vaccination, the estimated CRS incidence remains high elsewhere. Well-conducted seroprevalence studies can help to improve the reliability of these estimates and monitor the impact of rubella vaccination
A systematic review of biomarkers for disease progression in Parkinson's disease
Peer reviewedPublisher PD
Two Earth-sized planets orbiting Kepler-20
Since the discovery of the first extrasolar giant planets around Sun-like
stars, evolving observational capabilities have brought us closer to the
detection of true Earth analogues. The size of an exoplanet can be determined
when it periodically passes in front of (transits) its parent star, causing a
decrease in starlight proportional to its radius. The smallest exoplanet
hitherto discovered has a radius 1.42 times that of the Earth's radius (R
Earth), and hence has 2.9 times its volume. Here we report the discovery of two
planets, one Earth-sized (1.03R Earth) and the other smaller than the Earth
(0.87R Earth), orbiting the star Kepler-20, which is already known to host
three other, larger, transiting planets. The gravitational pull of the new
planets on the parent star is too small to measure with current
instrumentation. We apply a statistical method to show that the likelihood of
the planetary interpretation of the transit signals is more than three orders
of magnitude larger than that of the alternative hypothesis that the signals
result from an eclipsing binary star. Theoretical considerations imply that
these planets are rocky, with a composition of iron and silicate. The outer
planet could have developed a thick water vapour atmosphere.Comment: Letter to Nature; Received 8 November; accepted 13 December 2011;
Published online 20 December 201
Computational modelling of cancerous mutations in the EGFR/ERK signalling pathway
This article has been made available through the Brunel Open Access Publishing Fund - Copyright @ 2009 Orton et al.BACKGROUND: The Epidermal Growth Factor Receptor (EGFR) activated Extracellular-signal Regulated Kinase (ERK) pathway is a critical cell signalling pathway that relays the signal for a cell to proliferate from the plasma membrane to the nucleus. Deregulation of the EGFR/ERK pathway due to alterations affecting the expression or function of a number of pathway components has long been associated with numerous forms of cancer. Under normal conditions, Epidermal Growth Factor (EGF) stimulates a rapid but transient activation of ERK as the signal is rapidly shutdown. Whereas, under cancerous mutation conditions the ERK signal cannot be shutdown and is sustained resulting in the constitutive activation of ERK and continual cell proliferation. In this study, we have used computational modelling techniques to investigate what effects various cancerous alterations have on the signalling flow through the ERK pathway. RESULTS: We have generated a new model of the EGFR activated ERK pathway, which was verified by our own experimental data. We then altered our model to represent various cancerous situations such as Ras, B-Raf and EGFR mutations, as well as EGFR overexpression. Analysis of the models showed that different cancerous situations resulted in different signalling patterns through the ERK pathway, especially when compared to the normal EGF signal pattern. Our model predicts that cancerous EGFR mutation and overexpression signals almost exclusively via the Rap1 pathway, predicting that this pathway is the best target for drugs. Furthermore, our model also highlights the importance of receptor degradation in normal and cancerous EGFR signalling, and suggests that receptor degradation is a key difference between the signalling from the EGF and Nerve Growth Factor (NGF) receptors. CONCLUSION: Our results suggest that different routes to ERK activation are being utilised in different cancerous situations which therefore has interesting implications for drug selection strategies. We also conducted a comparison of the critical differences between signalling from different growth factor receptors (namely EGFR, mutated EGFR, NGF, and Insulin) with our results suggesting the difference between the systems are large scale and can be attributed to the presence/absence of entire pathways rather than subtle difference in individual rate constants between the systems.This work was funded by the Department of Trade and Industry (DTI), under their Bioscience Beacon project programme. AG was funded by an industrial PhD studentship from Scottish Enterprise and Cyclacel
Features of mammalian microRNA promoters emerge from polymerase II chromatin immunoprecipitation data
Background: MicroRNAs (miRNAs) are short, non-coding RNA regulators of protein coding genes. miRNAs play a very important role in diverse biological processes and various diseases. Many algorithms are able to predict miRNA genes and their targets, but their transcription regulation is still under investigation. It is generally believed that intragenic miRNAs (located in introns or exons of protein coding genes) are co-transcribed with their host genes and most intergenic miRNAs transcribed from their own RNA polymerase II (Pol II) promoter. However, the length of the primary transcripts and promoter organization is currently unknown. Methodology: We performed Pol II chromatin immunoprecipitation (ChIP)-chip using a custom array surrounding regions of known miRNA genes. To identify the true core transcription start sites of the miRNA genes we developed a new tool (CPPP). We showed that miRNA genes can be transcribed from promoters located several kilobases away and that their promoters share the same general features as those of protein coding genes. Finally, we found evidence that as many as 26% of the intragenic miRNAs may be transcribed from their own unique promoters. Conclusion: miRNA promoters have similar features to those of protein coding genes, but miRNA transcript organization is more complex. © 2009 Corcoran et al
The Effect of Visual Cues on Auditory Stream Segregation in Musicians and Non-Musicians
Background: The ability to separate two interleaved melodies is an important factor in music appreciation. This ability is greatly reduced in people with hearing impairment, contributing to difficulties in music appreciation. The aim of this study was to assess whether visual cues, musical training or musical context could have an effect on this ability, and potentially improve music appreciation for the hearing impaired. Methods: Musicians (N = 18) and non-musicians (N = 19) were asked to rate the difficulty of segregating a four-note repeating melody from interleaved random distracter notes. Visual cues were provided on half the blocks, and two musical contexts were tested, with the overlap between melody and distracter notes either gradually increasing or decreasing. Conclusions: Visual cues, musical training, and musical context all affected the difficulty of extracting the melody from a background of interleaved random distracter notes. Visual cues were effective in reducing the difficulty of segregating the melody from distracter notes, even in individuals with no musical training. These results are consistent with theories that indicate an important role for central (top-down) processes in auditory streaming mechanisms, and suggest that visual cue
Truncated Power Laws Reveal a Link between Low-Level Behavioral Processes and Grouping Patterns in a Colonial Bird
Background: Departures from power law group size frequency distributions have been proposed as a useful tool to link individual behavior with population patterns and dynamics, although examples are scarce for wild animal populations. Methodology/Principal Findings: We studied a population of Lesser kestrels (Falco naumanni) breeding in groups (colonies) from one to ca. 40 breeding pairs in 10,000 km 2 in NE Spain. A 3.5 fold steady population increase occurred during the eight-year study period, accompanied by a geographical expansion from an initial subpopulation which in turn remained stable in numbers. This population instability was mainly driven by first-breeders, which are less competitive at breeding sites, being relegated to breed solitarily or in small colony sizes, and disperse farther than adults. Colony size frequency distributions shifted from an initial power law to a truncated power law mirroring population increase. Thus, we hypothesized that population instability was behind the truncation of the power law. Accordingly, we found a power law distribution through years in the initial subpopulation, and a match between the power law breakpoint (at ca. ten pairs) and those colony sizes from which the despotic behavior of colony owners started to impair the settlement of newcomers. Moreover, the instability hypothesis was further supported by snapshot data from another population of Lesser kestrels in SW Spain suffering a population decline. Conclusions/Significance: Appropriate analysis of the scaling properties of grouping patterns has unraveled the lin
Expression of Distal-less, dachshund, and optomotor blind in Neanthes arenaceodentata (Annelida, Nereididae) does not support homology of appendage-forming mechanisms across the Bilateria
The similarity in the genetic regulation of
arthropod and vertebrate appendage formation has been
interpreted as the product of a plesiomorphic gene
network that was primitively involved in bilaterian
appendage development and co-opted to build appendages
(in modern phyla) that are not historically related
as structures. Data from lophotrochozoans are needed to
clarify the pervasiveness of plesiomorphic appendage forming
mechanisms. We assayed the expression of three
arthropod and vertebrate limb gene orthologs, Distal-less
(Dll), dachshund (dac), and optomotor blind (omb), in
direct-developing juveniles of the polychaete Neanthes
arenaceodentata. Parapodial Dll expression marks premorphogenetic
notopodia and neuropodia, becoming restricted
to the bases of notopodial cirri and to ventral
portions of neuropodia. In outgrowing cephalic appendages,
Dll activity is primarily restricted to proximal
domains. Dll expression is also prominent in the brain. dac
expression occurs in the brain, nerve cord ganglia, a pair
of pharyngeal ganglia, presumed interneurons linking a
pair of segmental nerves, and in newly differentiating
mesoderm. Domains of omb expression include the brain,
nerve cord ganglia, one pair of anterior cirri, presumed
precursors of dorsal musculature, and the same pharyngeal
ganglia and presumed interneurons that express dac.
Contrary to their roles in outgrowing arthropod and
vertebrate appendages, Dll, dac, and omb lack comparable
expression in Neanthes appendages, implying independent
evolution of annelid appendage development. We infer
that parapodia and arthropodia are not structurally or
mechanistically homologous (but their primordia might
be), that Dll’s ancestral bilaterian function was in sensory
and central nervous system differentiation, and that
locomotory appendages possibly evolved from sensory
outgrowths
Global biogeography of SAR11 marine bacteria
The ubiquitous SAR11 bacterial clade is the most abundant type of organism in the worldĝ€™s oceans, but the reasons for its success are not fully elucidated. We analysed 128 surface marine metagenomes, including 37 new Antarctic metagenomes. The large size of the data set enabled internal transcribed spacer (ITS) regions to be obtained from the Southern polar region, enabling the first global characterization of the distribution of SAR11, from waters spanning temperatures ĝ̂'2 to 30°C. Our data show a stable co-occurrence of phylotypes within both ĝ€̃ tropicalĝ€™ (>20°C) and ĝ€̃ polarĝ€™ (<10°C) biomes, highlighting ecological niche differentiation between major SAR11 subgroups. All phylotypes display transitions in abundance that are strongly correlated with temperature and latitude. By assembling SAR11 genomes from Antarctic metagenome data, we identified specific genes, biases in gene functions and signatures of positive selection in the genomes of the polar SAR11ĝ€"genomic signatures of adaptive radiation. Our data demonstrate the importance of adaptive radiation in the organismĝ€™s ability to proliferate throughout the worldĝ€™s oceans, and describe genomic traits characteristic of different phylotypes in specific marine biomes. © 2012 EMBO and Macmillan Publishers Limited All rights reserved
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