117 research outputs found

    Surgical Treatment of Iatrogenic Ventral Glottic Stenosis Using a Mucosal Flap Technique

    Get PDF
    OBJECTIVE: To describe a novel surgical technique for correcting postoperative ventral glottic stenosis (cicatrix or web formation) and the outcome in 2 Thoroughbred racehorses. STUDY DESIGN: Retrospective case report. ANIMALS: Thoroughbreds diagnosed with ventral glottic stenosis (n=2). METHODS: Horses presenting with iatrogenic ventral glottic stenosis and resultant exercise intolerance and abnormal exercise‐related noise were anesthetized and a midline sagittal skin incision was made over the ventral larynx and between the sternohyoideus muscles overlying the cricothyroid notch. The cricothyroid ligament, attached laryngeal cicatrix, and overlying mucosa were sagittally sectioned at the dorsal aspect of the cicatrix on the left side. The laryngeal mucosa, cicatrix, and underlying cricothyroid ligament immediately rostral and caudal to the cicatrix were sectioned in a medial (axial) direction as far as the right side of the cricothyroid notch. After resection of the majority of the attached cicatrix tissue, the residual mucosal flap (attached to the right side of the larynx) was reflected ventrally and sutured to the attachment of the cricothyroid ligament on the right side of the cricothyroid notch, creating an intact mucosal layer on the right side of the ventral larynx. RESULTS: Both horses had good intralaryngeal wound healing with minimal redevelopment of ventral glottic stenosis at 5 and 9 months postoperatively and were successfully returned to racing with complete absence of abnormal respiratory noise. CONCLUSION: The unique laryngeal anatomy of horses, with a cartilage‐free ventral laryngeal area (cricothyroid notch), allowed the use of this novel surgical technique to successfully treat ventral glottic stenosis

    Influences of Excluded Volume of Molecules on Signaling Processes on Biomembrane

    Get PDF
    We investigate the influences of the excluded volume of molecules on biochemical reaction processes on 2-dimensional surfaces using a model of signal transduction processes on biomembranes. We perform simulations of the 2-dimensional cell-based model, which describes the reactions and diffusion of the receptors, signaling proteins, target proteins, and crowders on the cell membrane. The signaling proteins are activated by receptors, and these activated signaling proteins activate target proteins that bind autonomously from the cytoplasm to the membrane, and unbind from the membrane if activated. If the target proteins bind frequently, the volume fraction of molecules on the membrane becomes so large that the excluded volume of the molecules for the reaction and diffusion dynamics cannot be negligible. We find that such excluded volume effects of the molecules induce non-trivial variations of the signal flow, defined as the activation frequency of target proteins, as follows. With an increase in the binding rate of target proteins, the signal flow varies by i) monotonically increasing; ii) increasing then decreasing in a bell-shaped curve; or iii) increasing, decreasing, then increasing in an S-shaped curve. We further demonstrate that the excluded volume of molecules influences the hierarchical molecular distributions throughout the reaction processes. In particular, when the system exhibits a large signal flow, the signaling proteins tend to surround the receptors to form receptor-signaling protein clusters, and the target proteins tend to become distributed around such clusters. To explain these phenomena, we analyze the stochastic model of the local motions of molecules around the receptor.Comment: 31 pages, 10 figure

    Depressive symptom trajectories among girls in the juvenile justice system: 24-month outcomes of an RCT of Multidimensional Treatment Foster Care

    Get PDF
    Youth depression is a significant and growing international public health problem. Youth who engage in high levels of delinquency are at particularly high risk for developing problems with depression. The present study examined the impact of a behavioral intervention designed to reduce delinquency (Multidimensional Treatment Foster Care; MTFC) compared to a group care intervention (GC; i.e., services as usual) on trajectories of depressive symptoms among adolescent girls in the juvenile justice system. MTFC has documented effects on preventing girls' recidivism, but its effects on preventing the normative rise in girls' depressive symptoms across adolescence have not been examined. This indicated prevention sample included 166 girls (13-17 years at T1) who had at least one criminal referral in the past 12 months and who were mandated to out-of-home care; girls were randomized to MTFC or GC. Intent-to-treat analyses examined the main effects of MTFC on depression symptoms and clinical cut-offs, and whether benefits were greatest for girls most at risk. Depressive symptom trajectories were specified in hierarchical linear growth models over a 2 year period using five waves of data at 6 month intervals. Depression clinical cut-off scores were specified as nonlinear probability growth models. Results showed significantly greater rates of deceleration for girls in MTFC versus GC for depressive symptoms and for clinical cut-off scores. The MTFC intervention also showed greater benefits for girls with higher levels of initial depressive symptoms. Possible mechanisms of effect are discussed, given MTFC's effectiveness on targeted and nontargeted outcomes. © 2013 Society for Prevention Research

    The effect of on-line position correction on the dose distribution in focal radiotherapy for bladder cancer

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The purpose of this study was to determine the dosimetric effect of on-line position correction for bladder tumor irradiation and to find methods to predict and handle this effect.</p> <p>Methods</p> <p>For 25 patients with unifocal bladder cancer intensity modulated radiotherapy (IMRT) with 5 beams was planned. The requirement for each plan was that 99% of the target volume received 95% of the prescribed dose. Tumor displacements from -2.0 cm to 2.0 cm in each dimension were simulated, using 0.5 cm increments, resulting in 729 simulations per patient. We assumed that on-line correction for the tumor was applied perfectly. We determined the correlation between the change in D<sub>99% </sub>and the change in path length, which is defined here as the distance from the skin to the isocenter for each beam. In addition the margin needed to avoid underdosage was determined and the probability that an underdosage occurs in a real treatment was calculated.</p> <p>Results</p> <p>Adjustments for tumor displacement with perfect on-line position correction resulted in an altered dose distribution. The altered fraction dose to the target varied from 91.9% to 100.4% of the prescribed dose. The mean D<sub>99% </sub>(± SD) was 95.8% ± 1.0%. There was a modest linear correlation between the difference in D<sub>99% </sub>and the change in path length of the beams after correction (R<sup>2 </sup>= 0.590). The median probability that a systematic underdosage occurs in a real treatment was 0.23% (range: 0 - 24.5%). A margin of 2 mm reduced that probability to < 0.001% in all patients.</p> <p>Conclusion</p> <p>On-line position correction does result in an altered target coverage, due to changes in average path length after position correction. An extra margin can be added to prevent underdosage.</p

    Comparing exercise interventions to increase persistence with physical exercise and sporting activity among people with hypertension or high normal blood pressure: study protocol for a randomised controlled trial

    Get PDF
    BACKGROUND: Increasing physical activity is known to have health benefits for people with hypertension and related conditions. Current general practitioner referrals for gym-based exercise increase physical activity but meta-analyses show that while these are effective the absolute health risk reduction is small due to patients failing to maintain activity levels over time. This study assesses the effectiveness of two sports-oriented interventions that are intended to bridge the intention-behaviour gap and thus increase the likelihood of sustained increases in physical activity. METHODS/DESIGN: Four-arm randomised controlled trial. The study tests two types of intervention that are intended to increase physical activity among currently inactive 18- to 74-year-old people with hypertension or high-normal blood pressure. This study will assess the effectiveness of a 12-week sports-oriented exercise programme, the efficacy of a web-delivered self-help tool to promote and support sports participation and healthy behaviour change and the effect of these interventions in combination. The control arm will be a standard care general practitioner referral for gym-based exercise. Participants will be allocated using block randomisation. The first author and primary analyst is blinded to participant allocation. The primary outcome measures will be time spent in physical activity assessed in metabolic equivalent minutes per week using the International Physical Activity Questionnaire 1 year after commencement of the intervention. Secondary outcomes include increased involvement in sporting activity and biomedical health outcomes including change in body mass index, and waist and hip measurement and reductions in blood pressure. DISCUSSION: If proven to be superior to general practitioner referrals for gym-based exercise, these sports-oriented interventions would constitute low-cost alternatives. The next stage would be a full economic evaluation of the interventions. TRIAL REGISTRATION: Current Controlled Trials ISRCTN71952900 (7 June 2013)

    Intensity-modulated radiation therapy: emerging cancer treatment technology

    Get PDF
    The use of intensity-modulated radiation therapy (IMRT) is rapidly advancing in the field of radiation oncology. Intensity-modulated radiation therapy allows for improved dose conformality, thereby affording the potential to decrease the spectrum of normal tissue toxicities associated with IMRT. Preliminary results with IMRT are quite promising; however, the clinical data is relatively immature and overall patient numbers remain small. High-quality IMRT requires intensive physics support and detailed knowledge of three-dimensional anatomy and patterns of tumour spread. This review focuses on basic principles, and highlights the clinical implementation of IMRT in head and neck and prostate cancer

    Why and how does shared language affect subsidiary knowledge inflows? A social identity perspective

    Get PDF
    We draw on social identity theory to conceptualize a moderated mediation model that examines the relationship between shared language among subsidiary and HQ managers, and subsidiaries’ knowledge inflows from HQ. Specifically, we study (1) whether this relationship is mediated by the extent to which subsidiary managers share HQ goals and vision, and the extent to which HR decisions are centralized; and (2) whether subsidiary type moderates these mediated relationships. Building on a sample of 817 subsidiaries in nine countries/regions, we find support for our model. Implications for research on HQ-subsidiary knowledge flows, social identity theory and international HRM are discussed

    Between the Vinča and Linearbandkeramik worlds: the diversity of practices and identities in the 54th–53rd centuries cal BC in south-west Hungary and beyond

    Get PDF
    Szederk&eacute;ny-Kukorica-dƱlƑ is a large settlement in south-east Transdanubia, Hungary, excavated in advance of road construction, which is notable for its combination of pottery styles, variously including Vinča A, RaĆŸi&scaron;te and LBK, and longhouses of a kind otherwise familiar from the LBK world. Formal modelling of its date establishes that the site probably began in the later 54th century cal BC, lasting until the first decades of the 52nd century cal BC. Occupation, featuring longhouses, pits and graves, probably began at the same time on the east and west parts of the settlement, the central part starting a decade or two later; the western part was probably abandoned last. Vinča pottery is predominantly associated with the east and central parts of the site, and RaĆŸi&scaron;te pottery with the west. Formal modelling of the early history and diaspora of longhouses in the LBK world suggests their emergence in the Formative LBK of Transdanubia c. 5500 cal BC and then rapid diaspora in the middle of the 54th century cal BC, associated with the &lsquo;earliest&rsquo; (&auml;lteste) LBK. The adoption of longhouses at Szederk&eacute;ny thus appears to come a few generations after the start of the diaspora. Rather than explaining the mixture of things, practices and perhaps people at Szederk&eacute;ny by reference to problematic notions such as hybridity, we propose instead a more fluid and varied vocabulary including combination and amalgamation, relationships and performance in the flow of social life, and networks; this makes greater allowance for diversity and interleaving in a context of rapid change
    • 

    corecore