176 research outputs found

    S1PR2 variants associated with auditory function in humans and endocochlear potential decline in mouse

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    Progressive hearing loss is very common in the population but we still know little about the underlying pathology. A new spontaneous mouse mutation (stonedeaf, stdf ) leading to recessive, early-onset progressive hearing loss was detected and exome sequencing revealed a Thr289Arg substitution in Sphingosine-1-Phosphate Receptor-2 (S1pr2). Mutants aged 2 weeks had normal hearing sensitivity, but at 4 weeks most showed variable degrees of hearing impairment, which became severe or profound in all mutants by 14 weeks. Endocochlear potential (EP) was normal at 2 weeks old but was reduced by 4 and 8 weeks old in mutants, and the stria vascularis, which generates the EP, showed degenerative changes. Three independent mouse knockout alleles of S1pr2 have been described previously, but this is the first time that a reduced EP has been reported. Genomic markers close to the human S1PR2 gene were significantly associated with auditory thresholds in the 1958 British Birth Cohort (n = 6099), suggesting involvement of S1P signalling in human hearing loss. The finding of early onset loss of EP gives new mechanistic insight into the disease process and suggests that therapies for humans with hearing loss due to S1P signalling defects need to target strial function

    Cardiac Procedures among American Indians and Alaska Natives compared to Non-Hispanic Whites Hospitalized with Ischemic Heart Disease in California

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    BackgroundAmerican Indians/Alaska Natives (AIAN) experience a high burden of cardiovascular disease with rates for fatal and nonfatal heart disease approximately twofold higher than the U.S. population.ObjectiveTo determine if disparities exist in cardiac procedure rates among AIAN compared to non-Hispanic whites hospitalized in California for ischemic heart disease defined as acute myocardial infarction or unstable angina.DesignCross-sectional study. EVENTS: A total of 796 ischemic heart disease hospitalizations among AIAN and 90971 among non-Hispanic whites in 37 of 58 counties in California from 1998-2002.MeasurementsCardiac catheterization, percutaneous cardiac intervention, and coronary artery bypass graft surgery procedure rates from hospitalization administrative data.Main resultsAIAN did not have lower cardiac procedure rates for cardiac catheterization and percutaneous cardiac intervention compared to non-Hispanic whites (unadjusted OR 1.00, 95% CI 0.87-1.16 and OR 1.04, 95% CI 0.90-1.20, respectively). Adjustment for age, sex, comorbidities, and payer source did not alter the results (adjusted OR 0.95, 95% CI 0.82-1.10 and OR 0.98, 95% CI 0.85-1.14, respectively). We found higher odds (unadjusted OR 1.36, 95% CI 1.09-1.70) for receipt of coronary artery bypass graft surgery among AIAN hospitalized for ischemic heart disease compared to non-Hispanic whites which after adjustment attenuated some and was no longer statistically significant (adjusted OR 1.26, 95% CI 1.00-1.58).ConclusionAIAN were not less likely to receive cardiac procedures as non-Hispanic whites during hospitalizations for ischemic heart disease. Additional research is needed to determine whether differences in specialty referral patterns, patients' treatment preferences, or outpatient management may explain some of the health disparities due to cardiovascular disease that is found among AIAN

    Premature Discontinuation of Prospective Clinical Studies Approved by a Research Ethics Committee - A Comparison of Randomised and Non-Randomised Studies.

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    Premature discontinuation of clinical studies affects about 25% of randomised controlled trials (RCTs) which raises concerns about waste of scarce resources for research. The risk of discontinuation of non-randomised prospective studies (NPSs) is yet unclear. To compare the proportion of discontinued studies between NPSs and RCTs that received ethical approval. We systematically surveyed prospective longitudinal clinical studies that were approved by a single REC in Freiburg, Germany between 2000 and 2002. We collected study characteristics, identified subsequent publications, and surveyed investigators to elucidate whether a study was discontinued and, if so, why. Of 917 approved studies, 547 were prospective longitudinal studies (306 RCTs and 241 NPSs). NPSs were on average smaller than RCTs, more frequently single centre and pilot studies, and less frequently funded by industry. NPSs were less frequently discontinued than RCTs: 32/221 (14%) versus 78/288 (27%, p<0.001, missing data excluded). Poor recruitment was the most frequent reason for discontinuation in both NPSs (36%) and RCTs (37%). Compared to RCTs, NPSs were at lower risk for discontinuation. Measures to reliably predict, sustain, and stimulate recruitment could prevent discontinuation of many RCTs but also of some NPSs

    Statistical Multiplicity in Systematic Reviews of Anaesthesia Interventions: A Quantification and Comparison between Cochrane and Non-Cochrane Reviews

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    BACKGROUND: Systematic reviews with meta-analyses often contain many statistical tests. This multiplicity may increase the risk of type I error. Few attempts have been made to address the problem of statistical multiplicity in systematic reviews. Before the implications are properly considered, the size of the issue deserves clarification. Because of the emphasis on bias evaluation and because of the editorial processes involved, Cochrane reviews may contain more multiplicity than their non-Cochrane counterparts. This study measured the quantity of statistical multiplicity present in a population of systematic reviews and aimed to assess whether this quantity is different in Cochrane and non-Cochrane reviews. METHODS/PRINCIPAL FINDINGS: We selected all the systematic reviews published by the Cochrane Anaesthesia Review Group containing a meta-analysis and matched them with comparable non-Cochrane reviews. We counted the number of statistical tests done in each systematic review. The median number of tests overall was 10 (interquartile range (IQR) 6 to 18). The median was 12 in Cochrane and 8 in non-Cochrane reviews (difference in medians 4 (95% confidence interval (CI) 2.0-19.0). The proportion that used an assessment of risk of bias as a reason for doing extra analyses was 42% in Cochrane and 28% in non-Cochrane reviews (difference in proportions 14% (95% CI -8 to 36). The issue of multiplicity was addressed in 6% of all the reviews. CONCLUSION/SIGNIFICANCE: Statistical multiplicity in systematic reviews requires attention. We found more multiplicity in Cochrane reviews than in non-Cochrane reviews. Many of the reasons for the increase in multiplicity may well represent improved methodological approaches and greater transparency, but multiplicity may also cause an increased risk of spurious conclusions. Few systematic reviews, whether Cochrane or non-Cochrane, address the issue of multiplicity

    The control of attentional target selection in a colour/colour conjunction task

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    To investigate the time course of attentional object selection processes in visual search tasks where targets are defined by a combination of features from the same dimension, we measured the N2pc component as an electrophysiological marker of attentional object selection during colour/colour conjunction search. In Experiment 1, participants searched for targets defined by a combination of two colours, while ignoring distractor objects that matched only one of these colours. Reliable N2pc components were triggered by targets and also by partially matching distractors, even when these distractors were accompanied by a target in the same display. The target N2pc was initially equal in size to the sum of the two N2pc components to the two different types of partially matching distractors, and became superadditive from about 250 ms after search display onset. Experiment 2 demonstrated that the superadditivity of the target N2pc was not due to a selective disengagement of attention from task-irrelevant partially matching distractors. These results indicate that attention was initially deployed separately and in parallel to all target-matching colours, before attentional allocation processes became sensitive to the presence of both matching colours within the same object. They suggest that attention can be controlled simultaneously and independently by multiple features from the same dimension, and that feature-guided attentional selection processes operate in parallel for different target-matching objects in the visual field

    Does Prehabilitation modify muscle mass in patients with rectal cancer undergoing neoadjuvant therapy?:A subanalysis from the REx Randomised Controlled Trial

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    Background: Patients with rectal cancer who present with sarcopenia (low muscle mass) are at significantly greater risk of postoperative complications and reduction in disease-free survival. We performed a subanalysis of a randomised controlled study [the REx trial; www.isrctn.com; 62859294] to assess the potential of prehabilitation to modify muscle mass in patients having neoadjuvant chemoradiotherapy (NACRT). Methods: Patients scheduled for NACRT, then potentially curative surgery (August 2014–March 2016) had baseline physical assessment and psoas muscle mass measurement (total psoas index using computed tomography-based measurements). Participants were randomised to either the intervention (13–17-week telephone-guided graduated walking programme) or control group (standard care). Follow-up testing was performed 1–2 weeks before surgery. Results: The 44 patients had a mean age of 66.8 years (SD 9.6) and were male (64%); white (98%); American Society of Anesthesiologists class 2 (66%); co-morbid (58%); overweight (72%) (body mass index ≥ 25 kg/m2). At baseline, 14% were sarcopenic. At follow-up, 13 (65%) of patients in the prehabilitation group had increased muscle mass versus 7 (35%) that experienced a decrease. Conversely, 16 (67%) controls experienced a decrease in muscle mass and 8 (33%) showed an increase. An adjusted linear regression model estimated a mean treatment difference in Total Psoas Index of 40.2mm2/m2 (95% CI − 3.4 to 83.7) between groups in change from baseline (p = 0.07). Conclusions: Prehabilitation improved muscle mass in patients with rectal cancer who had NACRT. These results need to be explored in a larger trial to determine if the poorer short- and long-term patient outcomes associated with low muscle mass can be minimised by prehabilitation

    Synaptic scaffold evolution generated components of vertebrate cognitive complexity

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    The origins and evolution of higher cognitive functions, including complex forms of learning, attention and executive functions, are unknown. A potential mechanism driving the evolution of vertebrate cognition early in the vertebrate lineage (550 million years ago) was genome duplication and subsequent diversification of postsynaptic genes. Here we report, to our knowledge, the first genetic analysis of a vertebrate gene family in cognitive functions measured using computerized touchscreens. Comparison of mice carrying mutations in each of the four Dlg paralogs showed that simple associative learning required Dlg4, whereas Dlg2 and Dlg3 diversified to have opposing functions in complex cognitive processes. Exploiting the translational utility of touchscreens in humans and mice, testing Dlg2 mutations in both species showed that Dlg2\u27s role in complex learning, cognitive flexibility and attention has been highly conserved over 100 million years. Dlg-family mutations underlie psychiatric disorders, suggesting that genome evolution expanded the complexity of vertebrate cognition at the cost of susceptibility to mental illness

    Electromagnetic Field Effect or Simply Stress? Effects of UMTS Exposure on Hippocampal Longterm Plasticity in the Context of Procedure Related Hormone Release

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    Harmful effects of electromagnetic fields (EMF) on cognitive and behavioural features of humans and rodents have been controversially discussed and raised persistent concern about adverse effects of EMF on general brain functions. In the present study we applied radio-frequency (RF) signals of the Universal Mobile Telecommunications System (UMTS) to full brain exposed male Wistar rats in order to elaborate putative influences on stress hormone release (corticosteron; CORT and adrenocorticotropic hormone; ACTH) and on hippocampal derived synaptic long-term plasticity (LTP) and depression (LTD) as electrophysiological hallmarks for memory storage and memory consolidation. Exposure was computer controlled providing blind conditions. Nominal brain-averaged specific absorption rates (SAR) as a measure of applied mass-related dissipated RF power were 0, 2, and 10 W/kg over a period of 120 min. Comparison of cage exposed animals revealed, regardless of EMF exposure, significantly increased CORT and ACTH levels which corresponded with generally decreased field potential slopes and amplitudes in hippocampal LTP and LTD. Animals following SAR exposure of 2 W/kg (averaged over the whole brain of 2.3 g tissue mass) did not differ from the sham-exposed group in LTP and LTD experiments. In contrast, a significant reduction in LTP and LTD was observed at the high power rate of SAR (10 W/kg). The results demonstrate that a rate of 2 W/kg displays no adverse impact on LTP and LTD, while 10 W/kg leads to significant effects on the electrophysiological parameters, which can be clearly distinguished from the stress derived background. Our findings suggest that UMTS exposure with SAR in the range of 2 W/kg is not harmful to critical markers for memory storage and memory consolidation, however, an influence of UMTS at high energy absorption rates (10 W/kg) cannot be excluded

    We can guide search by a set of colours, but are reluctant to do it.

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    For some real-world color searches, the target colours are not precisely known, and any item within a range of color values should be attended. This, a target representation that captures multiple similar colours would be advantageous. If such multicolour search is possible, then search for two targets (e..g Stroud, Menneer, Cave and Donnelly, 2012) might be guided by a target representation that included the target colours as well as the continuum of colours that fall between the targets within a contiguous region of color space. Results from Stroud et al (2012) suggest otherwise, however. The current set of experiments show that guidance for a set of colours that are from a single region of color space can be effective if targets are depicted as specific discrete colours. Specifically, Experiments 1-3 demonstrate that a search can be guided by four and even eight colours given the appropriate conditions. However, Experiment 5 gives evidence that guidance is sometimes sensitive to how informative the target preview is to search. Experiments 6 and 7 show that a stimulus showing a continuous range of target colours is not translated into a search target representation. Thus, search can be guided by multiple discrete colours that are from a single region in color space, but this approach was not adopted in a search for two targets with intervening distractor colours

    Is it feasible and effective to provide osteopathy and acupuncture for patients with musculoskeletal problems in a GP setting? A service evaluation

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    <p>Abstract</p> <p>Background</p> <p>Spinal manipulation and acupuncture can be helpful in reducing the symptoms of musculoskeletal (MSK) pain. Both approaches are currently recommended by NICE as treatment options for patients with persistent low back pain. However, there has been no previous evaluation of a GP service using them together for MSK pain. The purpose of this study was to evaluate acceptability and outcomes for an osteopathy and acupuncture service (delivered by complementary therapy practitioners) for patients with MSK problems provided within a General Practice.</p> <p>Methods</p> <p>Patients were asked to complete a questionnaire before and after their course of treatment. Outcome measures included the Bournemouth Questionnaire (measuring MSK problems), EuroQoL-5D (measuring quality of life), medication use, physical activity and general well-being. Non-parametric tests were used to compare pre- and post- treatment variables. Qualitative data, regarding participants' views on the service, were collected from patients via a service survey and healthcare professionals via interviews. Qualitative data were analysed using thematic analysis.</p> <p>Results</p> <p>123 adults with MSK problems were referred into the service (79 female and 44 male, mean age 49 years). Complete patient questionnaire data sets (pre- and post- treatment) were available for 102 participants; 91 completed a service survey. All healthcare professionals involved in the service participated in interviews including all seven GPs and the administration manager at the practice, as well as the three acupuncture/osteopathy practitioners.</p> <p>Patient outcomes: comparisons between pre and post-treatment revealed a statistically significant improvement in MSK pain (p < 0.0001) and quality of life (p < 0.0001), and a statistically significant reduction in medication use (p < 0.0001). Qualitative analysis found that patients reported improvements in their MSK pain, mobility, other physical health conditions, well-being and self-management of their MSK problem.</p> <p>Acceptability of the service: overall patients and healthcare professionals were satisfied with the service and its provision within the Practice. Patients reported wanting increased appointment availability and flexibility, and more sessions. Complementary therapy practitioners reported finding the high number of referrals of chronic patients challenging, and wanting increased communication with GPs.</p> <p>Conclusions</p> <p>Provision of acupuncture and osteopathy for MSK pain is achievable in General Practice. A GP surgery can quickly adapt to incorporate complementary therapy provided key principles are followed.</p
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