221 research outputs found

    Transoral endoscopic nasopharyngectomy with a flexible next-generation robotic surgical system

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    Objectives/Hypothesis: To determine the feasibility of transoral endoscopic nasopharyngectomy without division of the soft plate using a flexible, next-generation robotic surgical system. Study Design: Preclinical anatomic study using four human cadavers. Methods: Transoral resection of the nasopharyngeal wall with en-bloc resection of the cartilaginous Eustachian tube and dissection of the parapharyngeal fat space. Results: The first flexible robotic surgical system has recently been described. We performed a series of laboratory experiments to determine whether this flexible system could be used to perform transoral robotic nasopharyngectomy. This novel system allowed docking of the patient-side cart at the side of the operating table. The cannula tip was placed approximately 12 cm from the edge of the retractor pointing superiorly toward the nasopharynx (NP). Retraction of the soft palate anteriorly and tonsillar pillars laterally with stay sutures expanded the velopharyngeal inlet, providing adequate space to deploy all four instruments (three surgical instruments and a camera) into the NP for dissection. All instruments could be deployed into the NP, without collision or restriction of joint movement in this cadaver model. Using this position and docking location, the new flexible surgical robot provided sufficient access, reach, and visualization to complete robotic nasopharyngectomy with en-bloc resection of the cartilaginous Eustachian tube. Conclusion: This feasibility study showed that transoral endoscopic nasopharyngectomy could be performed without compromising the integrity of the soft palate using a novel flexible robotic surgical system. Level of Evidence: N/A. Laryngoscope, 126:2257–2262, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.postprin

    Face, content, construct validity and training effect of touch surgery (TM) as a surgical decision-making trainer for novices in open appendicectomy

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    Background Laparoscopic surgery has become the gold standard for many operations with significant benefits in morbidity and hospital recovery time. One such procedure is appendicectomy, which is overwhelmingly performed using the laparoscopic approach in the modern era. This has also meant that the number of cases involving traditional open appendicectomy has declined despite surgeons being expected to be able to convert to the open technique if required. One method to rehearse for theatre is the use of software applications. This paper investigates the validity of Touch Surgery™ as an education tool for surgical decision-making for novices, as well as its training effect in open appendicectomy. Method 70 participants will be recruited, consisting of 60 medical students (novices) and 10 surgical consultants (experts). For face, content, and construct validity, first attempt scores on the Touch Surgery™ Open Appendicectomy Test Module will be compared between novices and experts. For the training effect and knowledge decline elements of the study, novices will be further randomised into either the low intervention (control) group who will complete the simulation once, or to the high intervention group who will complete the simulation six times, with both novice groups asked to repeat the test one week later. All participants will also be requested to complete questionnaires regarding the stimulation

    Mercury DPM: fast, flexible particle simulations in complex geometries part II: applications

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    MercuryDPM is a particle-simulation software developed open-source by a global network of researchers. It was designed ​ab initio to simulate realistic geometries and materials, thus it contains several unique features not found in any other particle simulation software. These features have been discussed in a companion paper published in the DEM7 conference proceedings; here we present several challenging setups implemented in MercuryDPM ​ . Via these setups, we demonstrate the unique capability of the code to simulate and analyse highly complex geotechnical and industrial applications.These tups implemented include complex geometries such as (i) a screw conveyor, (ii) steady-state inflow conditions for chute flows, (iii) a confined conveyor belt to simulate a steady-state breaking wave, and(iii)aquasi-2D cylindrical slice to efficiently study shear flows.​MercuryDPM is also parallel, which we showcase via a multi-million particle simulations of a rotating drum. We further demonstrate how to simulate complex particle interactions, including: (i)deformable, charged clay particles; and (ii) liquid bridges and liquid migration in wet particulates, (iii) non-spherical particles implemented via superquadrics. Finally, we show how to analyse and complex systems using the unique micro-macro mapping (coarse-graining) tool MercuryCG

    Single-crosslink microscopy in a biopolymer network dissects local elasticity from molecular fluctuations

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    Polymer networks are fundamental from cellular biology to plastics technology but their intrinsic inhomogeneity is masked by the usual ensemble-averaged measurements. Here, we construct direct maps of crosslinks-symbolic depiction of spatially-distributed elements highlighting their physical features and the relationships between them-in an actin network. We selectively label crosslinks with fluorescent markers, track their thermal fluctuations, and characterize the local elasticity and cross-correlations between crosslinks. Such maps display massive heterogeneity, reveal abundant anticorrelations, and may contribute to address how local responses scale up to produce macroscopic elasticity. Single-crosslink microscopy offers a general, microscopic framework to better understand crosslinked molecular networks in undeformed or strained states

    A traditional Chinese medicine versus Western combination therapy in the treatment of rheumatoid arthritis: two-stage study protocol for a randomized controlled trial

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    <p>Abstract</p> <p>Background</p> <p>The common randomized controlled trial design has distinct limitations when applied to Chinese medicine, because Chinese medicine identifies and treats 'Chinese medicine patterns' rather than diagnosed diseases. Chinese medicine patterns are a group of associated symptoms, tongue appearances and pulse characteristics. These limitations could be overcome by developing new strategies to evaluate the effect of Chinese medicine. The idea behind pattern-based efficacy evaluations may optimize clinical trial design by identifying the responsiveness-related Chinese medicine patterns.</p> <p>Methods/Design</p> <p>This is a two-stage multi-center trial of Chinese herbal medicine for the management of rheumatoid arthritis. The stage one trial is an open-label trial and aims to explore what groups of Chinese medicine information (such as symptoms) correlates with better efficacy, and the stage two trial is a randomized, controlled, double-blind, double-dummy clinical trial that incorporates the efficacy-related information identified in the stage-one trial into the inclusion criteria.</p> <p>Discussion</p> <p>The indication of a Chinese herbal formula is a specific Chinese medicine pattern and not a single disease and stratifying a disease into several patterns with a group of symptoms is a feasible procedure in clinical trials. This study is the first to investigate whether this approach in the design of Chinese herbal medicine trials can improve responses.</p> <p>Trial registration</p> <p>ChiCTR-TRC-10000989</p

    Carotid artery plaque in women with rheumatoid arthritis and low estimated cardiovascular disease risk: a cross-sectional study

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    INTRODUCTION: We previously reported that most patients with rheumatoid arthritis (RA) and moderate cardiovascular disease (CVD) risk according to the Systematic COronary Evaluation score (SCORE) experience carotid artery plaque. In this study, we aimed to identify patient characteristics that can potentially predict carotid plaque presence in women with RA and a concurrent low CVD risk according to the SCORE. METHODS: A cohort of 144 women with an evaluated low risk of CVD (SCORE value of zero) was assembled amongst 550 consecutive patients with RA that underwent CVD risk factor recording and carotid artery ultrasound. Participants had no established CVD, moderate or severe chronic kidney disease, or diabetes. We assessed carotid plaque(s) presence and its associated patient characteristics. RESULTS: Carotid artery plaque was present in 35 (24.3%) of women with RA. Age, the number of synthetic disease-modifying agents (DMARDs) and total cholesterol concentrations were independently associated with plaque in multivariable stepwise backward regression analysis (odds ratio (95% confidence interval)=1.15 (1.07 to 1.24), P49.5 years or/and total cholesterol concentration of >5.4 mmol/l, respectively, compared to only 7.8% in those (n=64; 44.4%) with age≤49.5 years or/and total cholesterol concentration of ≤5.4 mmol/l, respectively. CONCLUSIONS: Approximately one-third of women with RA who experience a low SCORE value and are aged >49.5 years or/and have a total cholesterol concentration of >5.4 mmol/l, experience high-risk atherosclerosis, which requires intensive CVD risk management

    Nucleolar protein CSIG is required for p33ING1 function in UV-induced apoptosis

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    Cellular senescence-inhibited gene (CSIG) protein, a nucleolar protein with a ribosomal L1 domain in its N-terminus, can exert non-ribosomal functions to regulate biological processes, such as cellular senescence. Here, we describe a previously unknown function for CSIG: promotion of apoptosis in response to ultraviolet (UV) irradiation-induced CSIG upregulation. We identified p33ING1 as a binding partner that interacts with CSIG. After UV irradiation, p33ING1 increases its protein expression, translocates into the nucleolus and binds CSIG. p33ING1 requires its nucleolar targeting sequence region to interact with CSIG and enhance CSIG protein stability, which is essential for activation of downstream effectors, Bcl-2-associated X protein, to promote apoptosis. Thus, our data imply that p33ING1–CSIG axis functions as a novel pro-apoptotic regulator in response to DNA damage
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