2,637 research outputs found
Chromosome segregation errors generate a diverse spectrum of simple and complex genomic rearrangements
Cancer genomes are frequently characterized by numerical and structural chromosomal abnormalities. Here we integrated a centromere-specific inactivation approach with selection for a conditionally essential gene, a strategy termed CEN-SELECT, to systematically interrogate the structural landscape of mis-segregated chromosomes. We show that single-chromosome mis-segregation into a micronucleus can directly trigger a broad spectrum of genomic rearrangement types. Cytogenetic profiling revealed that mis-segregated chromosomes exhibit 120-fold-higher susceptibility to developing seven major categories of structural aberrations, including translocations, insertions, deletions, and complex reassembly through chromothripsis coupled to classical non-homologous end joining. Whole-genome sequencing of clonally propagated rearrangements identified random patterns of clustered breakpoints with copy-number alterations resulting in interspersed gene deletions and extrachromosomal DNA amplification events. We conclude that individual chromosome segregation errors during mitotic cell division are sufficient to drive extensive structural variations that recapitulate genomic features commonly associated with human disease
CUSUM: A tool for early feedback about performance?
BACKGROUND: Modern day clinical practice demands evidence justifying our choice of treatment methods. Cumulative sum techniques (cusum) are amongst the simplest statistical methods known. They provide rapid analysis and identification of trends in a series of data. This study highlights use of these techniques as an early performance indicator of a clinical procedure before its implementation. METHODS: Twenty consecutive patients who underwent total hip or knee arthroplasty received a simple dressing – blue gauze and Tegaderm. Cusum charting was used to assess the dressing with regards to skin blistering. At an acceptable level of performance the curve would oscillate about the horizontal axis and the overall trend therefore said to be flat. If performance is unacceptable, the cusum slopes upward. RESULTS: The cusum plot for the twenty patients did not cross the specified control limits. This showed that our simple dressing met specified standards with regards to wound blistering postoperatively. CONCLUSION: We recommend the use of this simple, yet versatile cusum technique in the early evaluation of a clinical procedure before its implementation
A feasibility trial to examine the social norms approach for the prevention and reduction of licit and illicit drug use in European University and college students.
Background: Incorrect perceptions of high rates of peer alcohol and tobacco use are predictive of increased personal use in student populations. Correcting misperceptions by providing feedback has been shown to be an effective intervention for reducing licit drug use. It is currently unknown if social norms interventions are effective in preventing and reducing illicit drug use in European students. The purpose of this paper is to describe the design of a multi-site cluster controlled trial of a web-based social norms intervention aimed at reducing licit and preventing illicit drug use in European university students.
Methods/Design: An online questionnaire to assess rates of drug use will be developed and translated based on existing social norms surveys. Students from sixteen universities in seven participating European countries will be invited to complete the questionnaire. Both intervention and control sites will be chosen by convenience. In each country, the intervention site will be the university that the local principal investigator is affiliated with. We aim to recruit 1000 students per site (baseline assessment). All participants will complete the online questionnaire at baseline. Baseline data will be used to develop social norms messages that will be included in a web-based intervention. The intervention group will receive individualized social norms feedback. The website will remain online during the following 5 months. After five months, a second survey will be conducted and effects of the intervention on social norms and drug use will be measured in comparison to the control site.
Discussion: This project is the first cross-national European collaboration to investigate the feasibility of a social norms intervention to reduce licit and prevent illicit drug use among European university students.
Final trial registration number
DRKS00004375 on the ‘German Clinical Trials Register’.This study is funded by the European Commission, Directorate General Justice, Freedom and Security (JLS/2009-2010/DPIP/AG
The BASES Expert Statement on the Effectiveness of Vision Training Programmes
Two types of vision training programmes exist, namely, generalised vision training (GVT) and sport-specific vision training (SVT). GVT programmes are designed to improve basic visual function (e.g., depth perception, motion perception and peripheral vision). A range of exercises is typically used by vision specialists such as optometrists and ophthalmologists. Although these specialists usually work to assist individuals with visual deficiencies, more recently the same methods have been used with athletes in an effort to improve sports performance. Whilst there is anecdotal support for the use of GVT programmes, there remains a paucity of empirical evidence to suggest that such training improves sports performance. Conversely, research on SVT has been shown to lead to task-specific improvements in sports performance (Smeeton et al., 2005; Williams et al., 2002). Here, we summarise scientific research that examines the utility of both types of training programmes for performance enhancement in sport
Logarithmic correction to BH entropy as Noether charge
We consider the role of the type-A trace anomaly in static black hole
solutions to semiclassical Einstein equation in four dimensions. Via Wald's
Noether charge formalism, we compute the contribution to the entropy coming
from the anomaly induced effective action and unveil a logarithmic correction
to the Bekenstein-Hawking area law.
The corrected entropy is given by a seemingly universal formula involving the
coefficient of the type-A trace anomaly, the Euler characteristic of the
horizon and the value at the horizon of the solution to the uniformization
problem for Q-curvature. Two instances are examined in detail: Schwarzschild
and a four-dimensional massless topological black hole. We also find agreement
with the logarithmic correction due to one-loop contribution of conformal
fields in the Schwarzschild background.Comment: 14 pages, JHEP styl
Psychosocial Factors Associated with Patterns of Smoking Surrounding Pregnancy in Fragile Families
Although research has documented factors associated with maternal smoking, we need a more in-depth understanding of the risk factors associated with changes in smoking behaviors during the postpartum period. We investigate smoking patterns during pregnancy and 1 year postpartum as a function of relevant psychosocial factors. We use data on 3,522 postpartum mothers from the Fragile Families and Child Wellbeing Study to analyze the predictors of smoking among mothers who did not smoke during pregnancy but smoked at 1 year postpartum, mothers who smoked both during pregnancy and postpartum, and mothers who did not smoke during either period. Our covariates are grouped into four categories of risk factors for smoking: socioeconomic status, health care, life course and health, and partner and social support. Postpartum mothers in our sample were more likely to smoke throughout or after their pregnancies if they had only a high school education or less, had a household income three or more times below the poverty line, had public or no health insurance, breastfed for less than 5 months, were not married to the infant’s father, if the infant’s father currently smoked, and if they attended religious services less than once a week. Mental health problems were consistently associated with an increased risk of constant and postpartum smoking relative to non-smoking. Psychosocial factors play a role in postpartum smoking, but they have a stronger effect in predicting smoking that persists throughout pregnancy and the first year postpartum
Primordial Black Holes: sirens of the early Universe
Primordial Black Holes (PBHs) are, typically light, black holes which can
form in the early Universe. There are a number of formation mechanisms,
including the collapse of large density perturbations, cosmic string loops and
bubble collisions. The number of PBHs formed is tightly constrained by the
consequences of their evaporation and their lensing and dynamical effects.
Therefore PBHs are a powerful probe of the physics of the early Universe, in
particular models of inflation. They are also a potential cold dark matter
candidate.Comment: 21 pages. To be published in "Quantum Aspects of Black Holes", ed. X.
Calmet (Springer, 2014
Spontaneous infection of a stable mediastinal cystic mass: A case report
Mediastinal cysts have an unpredictable course but can cause complications such as infection or local pressure effects. Persons with mediastinal cysts can be asymptomatic for many years or can develop symptoms as a result of complications of the cyst. There is a lack of consensus on the best approach to managing those patients without symptoms. In this case report, a 56 year old woman with an indolent mediastinal cyst initially managed conservatively suddenly developed symptoms suggestive of an infected mediastinal cyst requiring surgical resection
Pharmacoepidemiology and the Australian regional prevalence of multiple sclerosis
Background: Over some 50 years, field surveys have shown that the prevalence of multiple sclerosis (MS) increases with increasing distance from the equator in both the northern and the southern hemispheres. Such a latitudinal gradient has been found in field surveys of MS prevalence carried out at different times in various local regions of Australia
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