185 research outputs found
Teaching responsible conduct responsibly.
The advancement of science requires trust – trust in the literature, in our collaborators, in the data we are handed, and most of all in ourselves. Policies issued by U.S. federal funding agencies (e.g., the National Institutes of Health and National Science Foundation) have been valuable in prompting institutions to initiate formal mechanisms for providing instruction in the responsible conduct of research (RCR). However, the guidelines vary greatly in scope, detail, and the types of individuals to which they apply. Unfortunately, at many institutions, the provision of RCR instruction has become a bureaucratic exercise aimed at fulfilling a regulatory requirement, instead of an activity optimized for promoting a climate of integrity. We argue that for RCR instruction to be effective it should (1) be provided to everyone involved in the research enterprise, be they students, trainees, faculty, or staff, (2) be infused throughout one’s time at an institution. For graduate students, that would include from orientation to thesis completion, including integration into all “core classes” within their discipline, as well as into discussions at research group meetings. (3) We also advocate that the bulk of the instruction should be provided primarily by active researchers who know the issues and have relevance to, and credibly with, those being taught, and (4) that the instruction actively engages the learners. Not only will we be providing RCR instruction in a much more optimized manner, such an approach also emphasizes through our actions, not just in words, that behaving responsibly is an essential skill for researchers
Toward a Climate of Scientific Integrity
A review of the new edition of Macrina's "Scientific integrity: Text and cases in responsible conduct of research" highlights the continuing need for teaching ethical guidelines to young researchers
Protection of dopamine neurons by CDNF and neurturin variant N4 against MPP+ in dissociated cultures from rat mesencephalon
Parkinson's disease is associated with the loss of dopamine (DA) neurons in ventral mesencephalon. We have previously reported that no single neurotrophic factor we tested protected DA neurons from the dopaminergic toxin 1-methyl-4-phenylpyridinium (MPP+) in dissociated cultures isolated from the P0 rat substantia nigra, but that a combination of five neurotrophic factors was protective. We now report that cerebral DA neurotrophic factor (CDNF) and a variant of neurturin (NRTN), N4, were also not protective when provided alone but were protective when added together. In cultures isolated from the substantia nigra, MPP+ (10 mu M) decreased tyrosine hydroxylase-positive cells to 41.7 +/- 5.4% of vehicle control. Although treatment of cultures with 100 ng/ml of either CDNF or N4 individually before and after toxin exposure did not significantly increase survival in MPP+-treated cultures, when the two trophic factors were added together at 100 ng/ml each, survival of cells was increased 28.2 +/- 6.1% above the effect of MPP+ alone. In cultures isolated from the ventral tegmental area, another DA rich area, a higher dose of MPP+ (1 mM) was required to produce an EC50 in TH-positive cells but, as in the substantia nigra, only the combination of CDNF and N4 (100 ng/ml each) was successful at increasing the survival of these cells compared to MPP+ alone (by 22.5 +/- 3.5%). These data support previous findings that CDNF and N4 may be of therapeutic value for treatment of PD, but suggest that they may need to be administered together.Peer reviewe
Introductory comments for the scientific ethics theme.
In this letter, the three Guest Editors for JMBE's first-ever themed section introduce the topic of scientific ethics and decribe the organization of essays within the special section.\u
Melanoma cells break down LPA to establish local gradients that drive chemotactic dispersal.
The high mortality of melanoma is caused by rapid spread of cancer cells, which occurs unusually early in tumour evolution. Unlike most solid tumours, thickness rather than cytological markers or differentiation is the best guide to metastatic potential. Multiple stimuli that drive melanoma cell migration have been described, but it is not clear which are responsible for invasion, nor if chemotactic gradients exist in real tumours. In a chamber-based assay for melanoma dispersal, we find that cells migrate efficiently away from one another, even in initially homogeneous medium. This dispersal is driven by positive chemotaxis rather than chemorepulsion or contact inhibition. The principal chemoattractant, unexpectedly active across all tumour stages, is the lipid agonist lysophosphatidic acid (LPA) acting through the LPA receptor LPAR1. LPA induces chemotaxis of remarkable accuracy, and is both necessary and sufficient for chemotaxis and invasion in 2-D and 3-D assays. Growth factors, often described as tumour attractants, cause negligible chemotaxis themselves, but potentiate chemotaxis to LPA. Cells rapidly break down LPA present at substantial levels in culture medium and normal skin to generate outward-facing gradients. We measure LPA gradients across the margins of melanomas in vivo, confirming the physiological importance of our results. We conclude that LPA chemotaxis provides a strong drive for melanoma cells to invade outwards. Cells create their own gradients by acting as a sink, breaking down locally present LPA, and thus forming a gradient that is low in the tumour and high in the surrounding areas. The key step is not acquisition of sensitivity to the chemoattractant, but rather the tumour growing to break down enough LPA to form a gradient. Thus the stimulus that drives cell dispersal is not the presence of LPA itself, but the self-generated, outward-directed gradient
The affective modulation of motor awareness in anosognosia for hemiplegia : Behavioural and lesion evidence
© 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).The possible role of emotion in anosognosia for hemiplegia (i.e., denial of motor deficits contralateral to a brain lesion), has long been debated between psychodynamic and neurocognitive theories. However, there are only a handful of case studies focussing on this topic, and the precise role of emotion in anosognosia for hemiplegia requires empirical investigation. In the present study, we aimed to investigate how negative and positive emotions influence motor awareness in anosognosia. Positive and negative emotions were induced under carefully-controlled experimental conditions in right-hemisphere stroke patients with anosognosia for hemiplegia (n = 11) and controls with clinically normal awareness (n = 10). Only the negative, emotion induction condition resulted in a significant improvement of motor awareness in anosognosic patients compared to controls; the positive emotion induction did not. Using lesion overlay and voxel-based lesion-symptom mapping approaches, we also investigated the brain lesions associated with the diagnosis of anosognosia, as well as with performance on the experimental task. Anatomical areas that are commonly damaged in AHP included the right-hemisphere motor and sensory cortices, the inferior frontal cortex, and the insula. Additionally, the insula, putamen and anterior periventricular white matter were associated with less awareness change following the negative emotion induction. This study suggests that motor unawareness and the observed lack of negative emotions about one's disabilities cannot be adequately explained by either purely motivational or neurocognitive accounts. Instead, we propose an integrative account in which insular and striatal lesions result in weak interoceptive and motivational signals. These deficits lead to faulty inferences about the self, involving a difficulty to personalise new sensorimotor information, and an abnormal adherence to premorbid beliefs about the body.Peer reviewedFinal Published versio
The association between Type D personality and the metabolic syndrome: a cross-sectional study in a University-based outpatient lipid clinic
<p>Abstract</p> <p>Background</p> <p>Type D personality has been associated in the past with increased cardiovascular mortality among patients with established coronary heart disease. Very few studies have investigated the association of type D personality with traditional cardiovascular risk factors. In this study, we assessed the association between type D personality and the metabolic syndrome.</p> <p>Findings</p> <p>New consecutive patients referred to an outpatient lipid clinic for evaluation of possible metabolic syndrome were eligible for inclusion in the study. The metabolic syndrome was defined according to the International Diabetes Federation (IDF) diagnostic criteria. Type D personality was assessed with the DS-14 scale. Multivariate regression techniques were used to investigate the association between personality and metabolic syndromes adjusting for a number of medical and psychiatric confounders. Three hundred and fifty-nine persons were screened of whom 206 met the diagnostic criteria for the metabolic syndrome ("cases") and 153 did not ("control group"). The prevalence of type D personality was significantly higher in the cases as compared to the control group (44% versus 15% respectively, p < 0.001). In multivariate logistic regression analysis the presence of Type D personality was significantly associated with metabolic syndrome independently of other clinical factors, anxiety and depressive symptoms (odds ratio 3.47; 95% Confidence Interval: 1.90 - 6.33).</p> <p>Conclusions</p> <p>Type D personality was independently associated with the metabolic syndrome in this cross-sectional study. The potential implications of this finding, especially from a clinical or preventive perspective, should be examined in future research.</p
The North Staffordshire Osteoarthritis Project – NorStOP: Prospective, 3-year study of the epidemiology and management of clinical osteoarthritis in a general population of older adults
BACKGROUND: The clinical syndrome of joint pain and stiffness in older people is the commonest cause of disability and health care consultation in this age group. Yet there have been few prospective studies of its course over time and its impact on personal and social life. We plan a cohort study in the general population aged 50 years and over to determine the course and prognosis of hand, hip, knee and foot pain, and the impact of these syndromes on participation levels and health care use. METHODS: All patients aged 50 years and over registered with 3 local general practices are to be recruited to a population-based cohort study through the use of a two-stage mailing process. Participants will initially complete a "Health Survey" questionnaire. This will collect information on several areas of life including socio-demographics, general health, physical function, participation, and bodily pain. Those who state that they have experienced any hand problem or any pain in their hands, hips, knees, or feet in the previous 12 months, and also give permission to be re-contacted, will be mailed a "Regional Pains Survey" questionnaire which collects detailed information on the four selected body regions (hand, hips, knees, feet). Follow-up data for the three-year period subsequent to cohort recruitment will be collected through two sources: i) general practice medical records and ii) repeat mailed survey
Migraine and sleep apnea in the general population
Objective is to investigate the relationship between migraine and obstructive sleep apnea in the general population. A cross-sectional population-based study. A random age and gender stratified sample of 40,000 persons aged 20–80 years residing in Akershus, Hedmark or Oppland County, Norway, were drawn by the National Population Register. A postal questionnaire containing the Berlin Questionnaire was used to classify respondents to be of either high or low risk of obstructive sleep apnea. 376 persons with high risk and 157 persons with low risk of sleep apnea aged 30–65 years were included for further investigations. They underwent an extensive clinical interview, a physical and a neurological examination by physicians, and in-hospital polysomnography. Those with apnea hypopnoea index (AHI) ≥5 were classified with obstructive sleep apnea. Migraine without aura (MO) and migraine with aura (MA) was diagnosed according to the International Classification of Headache Disorders. MO and MA occurred in 12.5 and 6.8% of the participants with obstructive sleep apnea. The logistic regression analyses showed no relationship between the two types of migraine and obstructive sleep apnea, with adjusted odds ratios for MO 1.15 (0.65–2.06) and MA 1.15 (0.95–2.39). Further, estimates using cutoff of moderate (AHI ≥ 15) and severe (AHI ≥ 30) obstructive sleep apnea, did not reveal any significant relationship between migraine and the AHI. Migraine and obstructive sleep apnea are unrelated in the general population
A randomized, double-blind, placebo-controlled clinical trial to evaluate the efficacy and safety of neramexane in patients with moderate to severe subjective tinnitus
<p>Abstract</p> <p>Background</p> <p>Neramexane is a new substance that exhibits antagonistic properties at α<sub>9</sub>α<sub>10 </sub>cholinergic nicotinic receptors and <it>N</it>-methyl-D-aspartate receptors, suggesting potential efficacy in the treatment of tinnitus.</p> <p>Methods</p> <p>A total of 431 outpatients with moderate to severe subjective tinnitus (onset 3-18 months before screening) were assigned randomly to receive either placebo or neramexane mesylate (25 mg/day, 50 mg/day and 75 mg/day) for 16 weeks, with assessment at 4-week intervals. The primary (intention-to-treat) efficacy analysis was based on the change from baseline in Week 16 in the total score of the adapted German short version of the validated Tinnitus Handicap Inventory questionnaire (THI-12).</p> <p>Results</p> <p>Compared with placebo, the largest improvement was achieved in the 50 mg/d neramexane group, followed by the 75 mg/d neramexane group. This treatment difference did not reach statistical significance at the pre-defined endpoint in Week 16 (<it>p </it>= 0.098 for 50 mg/d; <it>p </it>= 0.289 for 75 mg/d neramexane), but consistent numerical superiority of both neramexane groups compared with placebo was observed. Four weeks after the end of treatment, THI-12 scores in the 50 mg/d group were significantly better than those of the controls. Secondary efficacy variables supported this trend, with <it>p </it>values of < 0.05 for the 50 mg/d neramexane group associated with the functional-communicational subscores of the THI-12 and the assessments of tinnitus annoyance and tinnitus impact on life as measured on an 11-point Likert-like scale. No relevant changes were observed for puretone threshold, for tinnitus pitch and loudness match, or for minimum masking levels. The 25 mg/d neramexane group did not differ from placebo. Neramexane was generally well tolerated and had no relevant influence on laboratory values, electrocardiography and vital signs. Dizziness was the most common adverse event and showed a clear dose-dependence.</p> <p>Conclusions</p> <p>This study demonstrated the safety and tolerability of neramexane treatment in patients with moderate to severe tinnitus. The primary efficacy variable showed a trend towards improvement of tinnitus suffering in the medium- and high-dose neramexane groups. This finding is in line with consistent beneficial effects observed in secondary assessment variables. These results allow appropriate dose selection for further studies.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov NCT00405886</p
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