Publications by authors named "James R Wilson"

21 Publications

  • Page 1 of 1

Multicentre, single-blind randomised controlled trial comparing MyndMove neuromodulation therapy with conventional therapy in traumatic spinal cord injury: a protocol study.

BMJ Open 2020 09 28;10(9):e039650. Epub 2020 Sep 28.

Toronto Rehabilitation Institute, University Health Network, Toronto, Ontario, Canada

Introduction: This protocol is describing a multicentre, single-blind randomised controlled trial. The objective is to compare the efficacy of MyndMove therapy versus conventional therapy (CT) in improving upper extremity function in individuals with C4-C7 traumatic, incomplete spinal cord injury (SCI). It is being conducted in two US and two Canadian SCI rehabilitation centres.

Methods And Analysis: Sixty people aged 18 years or older with a C4-C7 incomplete (AIS B-D) SCI between 4 months and 8 years postinjury are randomised to receive 40 sessions of MyndMove neuromodulation therapy or CT within a 14-week period of time. Therapy sessions are 1 hour in duration with a dose of 3-5 sessions per week. Assessments occur prior to randomisation, after 20 sessions, after 40 sessions and 10 weeks after the last session. The primary outcome measure is the efficacy of MyndMove therapy versus CT in improving upper extremity function as measured by Spinal Cord Independence Measure III: Self-Care subscore after 40 sessions. Secondary outcomes include: (1) improvements in the SCIM mobility subscore; (2) upper limb functions measured by Graded Redefined Assessment of Strength, Sensibility and Prehension and (3) Toronto Rehab Institute Hand Function Test; (4) To assess safety as measured by serious and non-serious adverse events recorded for participants in both groups of the study population over the duration of the study; (5) to compare the change in quality of life as measured by the Spinal Cord Injury-Quality of Life; and (6) to evaluate the impact on healthcare resource utilisation.

Ethics And Dissemination: All ethical approvals were obtained prior to enrolling any participants. Dissemination of the results of the study will be made at peer-reviewed academic meetings and through peer-reviewed medical journals TRIAL REGISTRATION NUMBER: NCT03439319.
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http://dx.doi.org/10.1136/bmjopen-2020-039650DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7523215PMC
September 2020

Management of the Patient with Chronic Spinal Cord Injury.

Med Clin North Am 2020 Mar 16;104(2):263-278. Epub 2019 Dec 16.

Spinal Cord Injuries and Disorders Center, Louis Stokes Cleveland VA Medical Center, 10701 East Boulevard, 128(W), Cleveland, OH 44106, USA; Department of Physical Medicine and Rehabilitation, Case Western Reserve University, MetroHealth System, Old Brooklyn Campus, 4229 Pearl Road, Cleveland, OH 44109, USA. Electronic address:

Individuals with spinal cord injuries or disorders (SCI/D), whether of traumatic or nontraumatic cause, require multidisciplinary management by their care team to achieve optimal health outcomes. SCI/D is relatively rare in the general population and primary care providers (PCPs) may not have extensive experience managing people with these disorders. Spinal cord injuries, impair the body's autonomic and biomechanical performance by interrupting the communications to and from major bodily systems. This article provides a framework to help PCPs understand how these changes impact their patient's physiologic function and subsequent risks for health complications with guidance for initial treatment approaches.
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http://dx.doi.org/10.1016/j.mcna.2019.10.006DOI Listing
March 2020

Cytotoxic and non-cytotoxic cardiac glycosides isolated from the combined flowers, leaves, and twigs of Streblus asper.

Bioorg Med Chem 2020 02 7;28(4):115301. Epub 2020 Jan 7.

Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States. Electronic address:

A new non-cytotoxic [(+)-17β-hydroxystrebloside (1)] and two known cytotoxic [(+)-3'-de-O-methylkamaloside (2) and (+)-strebloside (3)] cardiac glycosides were isolated and identified from the combined flowers, leaves, and twigs of Streblus asper collected in Vietnam, with the absolute configuration of 1 established from analysis of its ECD and NMR spectroscopic data and confirmed by computational ECD calculations. A new 14,21-epoxycardanolide (3a) was synthesized from 3 that was treated with base. A preliminary structure-activity relationship study indicated that the C-14 hydroxy group and the C-17 lactone unit and the established conformation are important for the mediation of the cytotoxicity of 3. Molecular docking profiles showed that the cytotoxic 3 and its non-cytotoxic analogue 1 bind differentially to Na/K-ATPase. Compound 3 docks deeply in the Na/K-ATPase pocket with a sole pose, and its C-10 formyl and C-5, C-14, and C-4' hydroxy groups may form hydrogen bonds with the side-chains of Glu111, Glu117, Thr797, and Arg880 of Na/K-ATPase, respectively. However, 1 fits the cation binding sites with at least three different poses, which all depotentiate the binding between 1 and Na/K-ATPase. Thus, 3 was found to inhibit Na/K-ATPase, but 1 did not. In addition, the cytotoxic and Na/K-ATPase inhibitory 3 did not affect glucose uptake in human lung cancer cells, against which it showed potent activity, indicating that this cardiac glycoside mediates its cytotoxicity by targeting Na/K-ATPase but not by interacting with glucose transporters.
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http://dx.doi.org/10.1016/j.bmc.2019.115301DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7029422PMC
February 2020

Structurally Modified Cyclopenta[]benzofuran Analogues Isolated from .

J Nat Prod 2019 10 17;82(10):2870-2877. Epub 2019 Oct 17.

Institute of Ecology and Biological Resources , Vietnamese Academy of Science and Technology , Hanoi , Vietnam.

Four new cyclopenta[]benzofuran derivatives based on an unprecedented carbon skeleton (-), with a dihydrofuran ring fused to dioxanyl and aryl rings, along with a new structural analogue () of 5‴-episilvestrol (episilvestrol, ), were isolated from an aqueous extract of a large-scale re-collection of the roots of collected in Vietnam. Compound demonstrated mutarotation in solution due to the presence of a hydroxy group at C-2‴, leading to the isolation of a racemic mixture, despite being purified on a chiral-phase HPLC column. Silvestrol () and episilvestrol () were isolated from the most potently cytotoxic chloroform subfraction of the roots. All new structures were elucidated using 1D and 2D NMR, HRESIMS, IR, UV, and ECD spectroscopic data. Of the five newly isolated compounds, only compound exhibited cytotoxic activity against a human colon cancer (HT-29) and human prostate cancer cell line (PC-3), with IC values of 2.3 μM in both cases. The isolated compounds (-) double the number of dioxanyl ring-containing rocaglate analogues reported to date from species and present additional information on the structural requirements for cancer cell line cytotoxicity within this compound class.
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http://dx.doi.org/10.1021/acs.jnatprod.9b00631DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6819999PMC
October 2019

Simulation model of the relationship between cesarean section rates and labor duration.

Health Care Manag Sci 2019 Dec 11;22(4):635-657. Epub 2018 Jul 11.

Department of Obstetrics and Gynecology, Duke University School of Medicine, Durham, NC, 27710, USA.

Cesarean delivery is the most common major abdominal surgery in many parts of the world, and it accounts for nearly one-third of births in the United States. For a patient who requires a C-section, allowing prolonged labor is not recommended because of the increased risk of infection. However, for a patient who is capable of a successful vaginal delivery, performing an unnecessary C-section can have a substantial adverse impact on the patient's future health. We develop two stochastic simulation models of the delivery process for women in labor; and our objectives are (i) to represent the natural progression of labor and thereby gain insights concerning the duration of labor as it depends on the dilation state for induced, augmented, and spontaneous labors; and (ii) to evaluate the Friedman curve and other labor-progression rules, including their impact on the C-section rate and on the rates of maternal and fetal complications. To use a shifted lognormal distribution for modeling the duration of labor in each dilation state and for each type of labor, we formulate a percentile-matching procedure that requires three estimated quantiles of each distribution as reported in the literature. Based on results generated by both simulation models, we concluded that for singleton births by nulliparous women with no prior complications, labor duration longer than two hours (i.e., the time limit for labor arrest based on the Friedman curve) should be allowed in each dilation state; furthermore, the allowed labor duration should be a function of dilation state.
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http://dx.doi.org/10.1007/s10729-018-9449-3DOI Listing
December 2019

Probabilistic sensitivity analysis on Markov models with uncertain transition probabilities: an application in evaluating treatment decisions for type 2 diabetes.

Health Care Manag Sci 2019 Mar 27;22(1):34-52. Epub 2017 Oct 27.

Department of Public Health Sciences, University of Virginia, 1300 Jefferson Park Avenue, Charlottesville, VA, 22908, USA.

Markov models are commonly used for decision-making studies in many application domains; however, there are no widely adopted methods for performing sensitivity analysis on such models with uncertain transition probability matrices (TPMs). This article describes two simulation-based approaches for conducting probabilistic sensitivity analysis on a given discrete-time, finite-horizon, finite-state Markov model using TPMs that are sampled over a specified uncertainty set according to a relevant probability distribution. The first approach assumes no prior knowledge of the probability distribution, and each row of a TPM is independently sampled from the uniform distribution on the row's uncertainty set. The second approach involves random sampling from the (truncated) multivariate normal distribution of the TPM's maximum likelihood estimators for its rows subject to the condition that each row has nonnegative elements and sums to one. The two sampling methods are easily implemented and have reasonable computation times. A case study illustrates the application of these methods to a medical decision-making problem involving the evaluation of treatment guidelines for glycemic control of patients with type 2 diabetes, where natural variation in a patient's glycated hemoglobin (HbA1c) is modeled as a Markov chain, and the associated TPMs are subject to uncertainty.
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http://dx.doi.org/10.1007/s10729-017-9420-8DOI Listing
March 2019

Poster 467 Delayed Diagnosis of Cervical Anterior Cord Syndrome in a Child with Combined Traumatic Brain and Spinal Cord Injury: A Case Report.

PM R 2016 Sep 24;8(9S):S312-S313. Epub 2016 Sep 24.

The Children's Hospital of Philadelphia, Philadelphia, PA, United States.

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http://dx.doi.org/10.1016/j.pmrj.2016.07.388DOI Listing
September 2016

Poster 405 Prolongation of Botulinum Toxin Effect with Zinc Supplementation: A Case Report.

PM R 2016 Sep 24;8(9S):S294. Epub 2016 Sep 24.

Temple University Hospital, Philadelphia, PA, United States.

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http://dx.doi.org/10.1016/j.pmrj.2016.07.332DOI Listing
September 2016

Poster 321 Trazodone Associated Clitoral Priapism in a Transgender Man following Traumatic Brain Injury: A Case Report.

PM R 2016 Sep 24;8(9S):S265. Epub 2016 Sep 24.

Temple University Hospital / MossRehab Hospital, Philadelphia, PA, United States.

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http://dx.doi.org/10.1016/j.pmrj.2016.07.491DOI Listing
September 2016

A stochastic model of acute-care decisions based on patient and provider heterogeneity.

Health Care Manag Sci 2017 Jun 21;20(2):187-206. Epub 2015 Oct 21.

Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.

The primary cause of preventable death in many hospitals is the failure to recognize and/or rescue patients from acute physiologic deterioration (APD). APD affects all hospitalized patients, potentially causing cardiac arrest and death. Identifying APD is difficult, and response timing is critical - delays in response represent a significant and modifiable patient safety issue. Hospitals have instituted rapid response systems or teams (RRT) to provide timely critical care for APD, with thresholds that trigger the involvement of critical care expertise. The National Early Warning Score (NEWS) was developed to define these thresholds. However, current triggers are inconsistent and ignore patient-specific factors. Further, acute care is delivered by providers with different clinical experience, resulting in quality-of-care variation. This article documents a semi-Markov decision process model of APD that incorporates patient and provider heterogeneity. The model allows for stochastically changing health states, while determining patient subpopulation-specific RRT-activation thresholds. The objective function minimizes the total time associated with patient deterioration and stabilization; and the relative values of nursing and RRT times can be modified. A case study from January 2011 to December 2012 identified six subpopulations. RRT activation was optimal for patients in "slightly concerning" health states (NEWS > 0) for all subpopulations, except surgical patients with low risk of deterioration for whom RRT was activated in "concerning" states (NEWS > 4). Clustering methods identified provider clusters considering RRT-activation preferences and estimation of stabilization-related resource needs. Providers with conservative resource estimates preferred waiting over activating RRT. This study provides simple practical rules for personalized acute care delivery.
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http://dx.doi.org/10.1007/s10729-015-9347-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5415592PMC
June 2017

Competing risks analysis in mortality estimation for breast cancer patients from independent risk groups.

Health Care Manag Sci 2014 Sep 19;17(3):259-69. Epub 2013 Nov 19.

Department of Industrial Engineering, University of Arkansas, Fayetteville, AR, 72701, USA,

This study quantifies breast cancer mortality in the presence of competing risks for complex patients. Breast cancer behaves differently in different patient populations, which can have significant implications for patient survival; hence these differences must be considered when making screening and treatment decisions. Mortality estimation for breast cancer patients has been a significant research question. Accurate estimation is critical for clinical decision making, including recommendations. In this study, a competing risks framework is built to analyze the effect of patient risk factors and cancer characteristics on breast cancer and other cause mortality. To estimate mortality probabilities from breast cancer and other causes as a function of not only the patient's age or race but also biomarkers for estrogen and progesterone receptor status, a nonparametric cumulative incidence function is formulated using data from the community-based Carolina Mammography Registry. Based on the log(-log) transformation, confidence intervals are constructed for mortality estimates over time. To compare mortality probabilities in two independent risk groups at a given time, a method with improved power is formulated using the log(-log) transformation.
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http://dx.doi.org/10.1007/s10729-013-9255-xDOI Listing
September 2014

Multifunctional Polymer-Coated Carbon Nanotubes for Safe Drug Delivery.

Part Part Syst Charact 2013 Apr 28;30(4):365-373. Epub 2013 Feb 28.

Department of Bioengineering, Clemson University, Clemson, SC, 29634, USA.

Though progress in the use carbon nanotubes in medicine has been most encouraging for therapeutic and diagnostic applications, any translational success must involve overcoming the toxicological and surface functionalization challenges inherent in the use of such nanotubes. Ideally, a carbon nanotube-based drug delivery system would exhibit low toxicity, sustained drug release, and persist in circulation without aggregation. We report a carbon nanotube (CNT) coated with a biocompatible block-co-polymer composed of poly(lactide)-poly(ethylene glycol) (PLA-PEG) to reduce short-term and long-term toxicity, sustain drug release of paclitaxel (PTX), and prevent aggregation. The copolymer coating on the surface of CNTs significantly reduces toxicity in human umbilical vein endothelial cells (HUVEC) and U-87 glioblastoma cells. Moreover, coating reduces inflammatory response in rat lung epithelial cells. Compared to non-coated CNTs, studies show no long-term inflammatory response with CNT coated with PLA-PEG (CLP) and the surface coating significantly decreases acute toxicity by doubling the maximum tolerated dose in mice. Using polymer coatings, we can encapsulate PTX and release over one week to increase the therapeutic efficacy compared to free drugs. biodistribution and histology studies suggests a lower degree of aggregation in tissues in that CLP accumulate more in the brain and less in the spleen than the CNT-PLA (CL) formulation.
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http://dx.doi.org/10.1002/ppsc.201200145DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5022564PMC
April 2013

Measurement of the membrane potential in small cells using patch clamp methods.

Channels (Austin) 2011 Nov-Dec;5(6):530-7. Epub 2011 Nov 1.

University of Calgary, AB, Canada.

The resting membrane potential, E(m), of mammalian cells is a fundamental physiological parameter. Even small changes in E(m) can modulate excitability, contractility and rates of cell migration. At present accurate, reproducible measurements of E(m) and determination of its ionic basis remain significant challenges when patch clamp methods are applied to small cells. In this study, a mathematical model has been developed which incorporates many of the main biophysical principles which govern recordings of the resting potential of 'small cells'. Such a prototypical cell (approx. capacitance, 6 pF; input resistance 5 GΩ) is representative of neonatal cardiac myocytes, and other cells in the cardiovascular system (endothelium, fibroblasts) and small cells in other tissues, e.g. bone (osteoclasts) articular joints (chondrocytes) and the pancreas (β cells). Two common experimental conditions have been examined: (1) when the background K(+) conductance is linear; and (2) when this K(+) conductance is highly nonlinear and shows pronounced inward rectification. In the case of a linear K(+) conductance, the presence of a "leakage" current through the seal resistance between the cell membrane and the patch pipette always depolarizes E(m). Our calculations confirm that accurate characterization of E(m) is possible when the seal resistance is at least 5 times larger than the input resistance of the targeted cell. Measurement of E(m) under conditions in which the main background current includes a markedly nonlinear K(+) conductance (due to inward rectification) yields complex and somewhat counter-intuitive findings. In fact, there are at least two possible stable values of resting membrane potential for a cell when the nonlinear, inwardly rectifying K(+) conductance interacts with the seal current. This type of bistable behavior has been reported in a variety of small mammalian cells, including those from the heart, endothelium, smooth muscle and bone. Our theoretical treatment of these two common experimental situations provides useful mechanistic insights, and suggests practical methods by which these significant limitations, and their impact, can be minimized.
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http://dx.doi.org/10.4161/chan.5.6.17484DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3265801PMC
June 2012

Three-dimensional analysis of solid oxide fuel cell Ni-YSZ anode interconnectivity.

Microsc Microanal 2009 Feb;15(1):71-7

Department of Materials Science, Northwestern University, 2220 Campus Dr., Evanston, IL 60208, USA.

A method is described for quantitatively analyzing the level of interconnectivity of solid-oxide fuel cell electrode phases. The method was applied to the three-dimensional microstructure of a Ni-Y2O3-stabilized ZrO2 (Ni-YSZ) anode active layer measured by focused ion beam scanning electron microscopy. Each individual contiguous network of Ni, YSZ, and porosity was identified and labeled according to whether it was contiguous with the rest of the electrode. It was determined that the YSZ phase was 100% connected, whereas at least 86% of the Ni and 96% of the pores were connected. Triple-phase boundary (TPB) segments were identified and evaluated with respect to the contiguity of each of the three phases at their locations. It was found that 11.6% of the TPB length was on one or more isolated phases and hence was not electrochemically active.
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http://dx.doi.org/10.1017/S1431927609090096DOI Listing
February 2009

Clinical judgment analysis of the parameters used by consultant urologists in the management of prostate cancer.

J Urol 2007 Jul 11;178(1):98-102. Epub 2007 May 11.

Department of Urology, Taunton and Somerset Hospital, Taunton, United Kingdom.

Purpose: We assessed which clinical parameters consultant urologists use to recommend treatment for early prostate cancer.

Materials And Methods: A total of 30 consultant urologists reviewed 70 paper representations of patients with prostate cancer. Each contained 7 commonly available cues, including prostate specific antigen, Gleason grade, rectal examination, magnetic resonance imaging/laparoscopic stage, medical history, patient choice and age, in addition to 2 cues not yet routinely available, that is predicted life expectancy and 10-year survival probability, as calculated using actuarial formulas based on noncancer comorbidity. Consultants indicated how strongly they would recommend radical prostatectomy, radiotherapy with or without hormones, or active surveillance/hormones. Judgment analysis was performed using multiple regression analysis with significance considered at p
Results: Consultants varied in the treatments that they recommended. An average of only 3 of the possible 9 cues was used to formulate decisions. Prostate specific antigen and predicted 10-year survival probability were most commonly used for recommending all 3 treatment options. Patient choice, predicted life expectancy, rectal examination and age were all used infrequently. Consultants were inconsistent in an average of 31.4% of judgments when repeat cases were analyzed with the greatest inconsistency observed when recommending radiotherapy with or without hormones and the least inconsistency when recommending radical prostatectomy.

Conclusions: Consultants were inconsistent in their decisions regarding the management of early prostate cancer and they used only a small number of available clinical parameters. Ensuring that all relevant information is available and providing clinicians with further education and training would ensure that treatment decisions become more reliable, appropriate and targeted toward patient choice.
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http://dx.doi.org/10.1016/j.juro.2007.03.029DOI Listing
July 2007

Three-dimensional reconstruction of a solid-oxide fuel-cell anode.

Nat Mater 2006 Jul 11;5(7):541-4. Epub 2006 Jun 11.

Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA.

The drive towards increased energy efficiency and reduced air pollution has led to accelerated worldwide development of fuel cells. As the performance and cost of fuel cells have improved, the materials comprising them have become increasingly sophisticated, both in composition and microstructure. In particular, state-of-the-art fuel-cell electrodes typically have a complex micro/nano-structure involving interconnected electronically and ionically conducting phases, gas-phase porosity, and catalytically active surfaces. Determining this microstructure is a critical, yet usually missing, link between materials properties/processing and electrode performance. Current methods of microstructural analysis, such as scanning electron microscopy, only provide two-dimensional anecdotes of the microstructure, and thus limited information about how regions are interconnected in three-dimensional space. Here we demonstrate the use of dual-beam focused ion beam-scanning electron microscopy to make a complete three-dimensional reconstruction of a solid-oxide fuel-cell electrode. We use this data to calculate critical microstructural features such as volume fractions and surface areas of specific phases, three-phase boundary length, and the connectivity and tortuosity of specific subphases.
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http://dx.doi.org/10.1038/nmat1668DOI Listing
July 2006

Low-level exertions of the neck musculature: a study of research methods.

J Electromyogr Kinesiol 2006 Oct 24;16(5):485-97. Epub 2006 Feb 24.

Department of Industrial Engineering, North Carolina State University, Raleigh, NC 27695-7906, USA.

Musculoskeletal neck discomfort is prevalent in many occupations and has been the focus of much research employing surface electromyography (sEMG). Significant differences in experimental methods among researchers make comparisons across studies difficult. The goal of the current research was to use empirical methods to answer specific methodological questions concerning use of sEMG in evaluation of the neck extensor system. This was accomplished in two studies. In Experiment 1, ultrasound technology was used to: (a) determine accessibility of m. splenius and semispinalis capitis with surface electrodes, (b) identify appropriate electrode locations for these muscles/muscle groups, and (c) illustrate potential benefits of using ultrasound in locating muscles/placing electrodes. Experiment 2 sought to assess effects of posture when normalizing sEMG data. Results from Experiment 1 showed no direct access to semispinalis capitis for surface electrodes; their activity can only be sampled as part of a group of muscles. In most subjects, m. splenius was found to be accessible to surface electrodes. Electrode placement recommendations are provided. Results of Experiment 2 showed significant differences in normalized EMG data between a posture-specific technique and a reference posture technique. Posture-specific normalization is recommended for accurately assessing the relative intensity of contractions of these muscles.
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http://dx.doi.org/10.1016/j.jelekin.2005.09.007DOI Listing
October 2006

Human frequency-following responses to binaural masking level difference stimuli.

J Am Acad Audiol 2005 Mar;16(3):184-95

Department of Audiology and Speech Sciences, Purdue University, West Lafayette, IN 47907, USA.

Binaural masking level difference is the behavioral threshold difference between a diotic condition (SoNo) and a dichotic condition with a 180 degrees interaural phase delay of either the signal (SpiNo) or the masker (SoNpi). Threshold disparity is partially related to coincidence-detecting units in the medial superior olive that are sensitive to low-frequency binaural stimuli with interaural phase differences. Previous surface evoked potential studies report significant latency and amplitude differences to SpiNo stimuli with respect to SoNo stimuli in the P1-N1 auditory event related potential, but no study has reported physiologic masking level differences in a brain stem evoked potential. The human frequency-following response (FFR) represents activity from low-frequency, phase locking neural units in the upper brainstem. Unmasked FFRs to 500 Hz tone bursts and masked FFRs using a 1.5 kHz low-pass masker were recorded from nine normal-hearing adult subjects. Significant reduction in FFR amplitude occurred in the SoNo condition, re the So condition, with masker intensities near the psychoacoustic SoNo masking level. Significant FFR amplitude recovery was observed for both the SoNpi and SpiNo conditions. These results support the role of phase-locked neural activity in brainstem mechanisms involved in perceptual masking release.
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http://dx.doi.org/10.3766/jaaa.16.3.6DOI Listing
March 2005

The assessment of patient life-expectancy: how accurate are urologists and oncologists?

BJU Int 2005 Apr;95(6):794-8

Department of Urology, Taunton & Somerset Hospital, Musgrove Park, Taunton, TA1 5DA, UK.

Objective: To assess the degree of accuracy, precision and consistency with which consultant urologists, oncologists and junior doctors predict a patient's 10-year life-expectancy.

Subjects And Methods: Eighteen doctors of varying seniority independently examined 70 patient case scenarios containing detailed medical histories; 13 of these cases were duplicate scenarios. Bland-Altman analyses were used to compare doctors' estimates of the probability of each hypothetical patient surviving 10 years with that calculated using actuarial methods. Intra- and interdoctor reliability were also assessed.

Results: Compared with actuarial estimates, doctors underestimated the 10-year survival probability by an overall mean of 10.8% (95% confidence interval, 10.1-11.5%). The 18 individual doctors ranged from a mean underestimation of 33.2% to a mean overestimation of 3.9%. Variation around these means was considerable for each doctor, the standard deviations being 14.5-20.9%. Inter-doctor reliability was 0.58, while overall intra-doctor reliability was 0.74, but for individual doctors was 0.31-0.94. Junior doctors were less accurate in their predictions than the senior doctors. Five doctors tended to overestimate where life-expectancy was poor and underestimate where it was good.

Conclusions: Doctors were poor at predicting 10-year survival, tending to underestimate when compared with actuarial estimates. There was also substantial variability both within and between doctors. The inaccuracy, imprecision and inconsistency amongst the doctors in assessing patient life-expectancy is an important finding and has significant implications for managing patients. Many patients may be denied treatment after a pessimistic assessment of life-expectancy and (less commonly) some may inappropriately be offered treatment after an optimistic assessment. The particular inaccuracy in junior doctors compared with their senior colleagues also highlights the need for training. The development of a tool to assist in both training and clinical practice has the potential to improve doctors' decision-making and patient care.
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http://dx.doi.org/10.1111/j.1464-410X.2005.05403.xDOI Listing
April 2005

Responsible authorship and peer review.

Authors:
James R Wilson

Sci Eng Ethics 2002 Apr;8(2):155-74

Department of Industrial Engineering, 2401 Stinson Drive, Riddick Labs 328, North Carolina State University, Raleigh, NC 27695-7906, USA.

In this article the basic principles of responsible authorship and peer review are surveyed, with special emphasis on (a) guidelines for refereeing archival journal articles and proposals; and (b) how these guidelines should be taken into account at all stages of writing.
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http://dx.doi.org/10.1007/s11948-002-0016-3DOI Listing
April 2002