21 research outputs found

    LUMiC(A (R)) Endoprosthetic Reconstruction After Periacetabular Tumor Resection:Short-term Results

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    Reconstruction of periacetabular defects after pelvic tumor resection ranks among the most challenging procedures in orthopaedic oncology, and reconstructive techniques are generally associated with dissatisfying mechanical and nonmechanical complication rates. In an attempt to reduce the risk of dislocation, aseptic loosening, and infection, we introduced the LUMiC(A (R)) prosthesis (implantcast, Buxtehude, Germany) in 2008. The LUMiC(A (R)) prosthesis is a modular device, built of a separate stem (hydroxyapatite-coated uncemented or cemented) and acetabular cup. The stem and cup are available in different sizes (the latter of which is also available with silver coating for infection prevention) and are equipped with sawteeth at the junction to allow for rotational adjustment of cup position after implantation of the stem. Whether this implant indeed is durable at short-term followup has not been evaluated. (1) What proportion of patients experience mechanical complications and what are the associated risk factors of periacetabular reconstruction with the LUMiC(A (R)) after pelvic tumor resection? (2) What proportion of patients experience nonmechanical complications and what are the associated risk factors of periacetabular reconstruction with the LUMiC(A (R)) after pelvic tumor resection? (3) What is the cumulative incidence of implant failure at 2 and 5 years and what are the mechanisms of reconstruction failure? (4) What is the functional outcome as assessed by Musculoskeletal Tumor Society (MSTS) score at final followup? We performed a retrospective chart review of every patient in whom a LUMiC(A (R)) prosthesis was used to reconstruct a periacetabular defect after internal hemipelvectomy for a pelvic tumor from July 2008 to June 2014 in eight centers of orthopaedic oncology with a minimum followup of 24 months. Forty-seven patients (26 men [55%]) with a mean age of 50 years (range, 12-78 years) were included. At review, 32 patients (68%) were alive. The reverse Kaplan-Meier method was used to calculate median followup, which was equal to 3.9 years (95% confidence interval [CI], 3.4-4.3). During the period under study, our general indications for using this implant were reconstruction of periacetabular defects after pelvic tumor resections in which the medial ilium adjacent to the sacroiliac joint was preserved; alternative treatments included hip transposition and saddle or custom-made prostheses in some of the contributing centers; these were generally used when the medial ilium was involved in the tumorous process or if the LUMiC(A (R)) was not yet available in the specific country at that time. Conventional chondrosarcoma was the predominant diagnosis (n = 22 [47%]); five patients (11%) had osseous metastases of a distant carcinoma and three (6%) had multiple myeloma. Uncemented fixation (n = 43 [91%]) was preferred. Dual-mobility cups (n = 24 [51%]) were mainly used in case of a higher presumed risk of dislocation in the early period of our study; later, dual-mobility cups became the standard for the majority of the reconstructions. Silver-coated acetabular cups were used in 29 reconstructions (62%); because only the largest cup size was available with silver coating, its use depended on the cup size that was chosen. We used a competing risk model to estimate the cumulative incidence of implant failure. Six patients (13%) had a single dislocation; four (9%) had recurrent dislocations. The risk of dislocation was lower in reconstructions with a dual-mobility cup (one of 24 [4%]) than in those without (nine of 23 [39%]) (hazard ratio, 0.11; 95% CI, 0.01-0.89; p = 0.038). Three patients (6%; one with a preceding structural allograft reconstruction, one with poor initial fixation as a result of an intraoperative fracture, and one with a cemented stem) had loosening and underwent revision. Infections occurred in 13 reconstructions (28%). Median duration of surgery was 6.5 hours (range, 4.0-13.6 hours) for patients with an infection and 5.3 hours (range, 2.8-9.9 hours) for those without (p = 0.060); blood loss was 2.3 L (range, 0.8-8.2 L) for patients with an infection and 1.5 L (range, 0.4-3.8 L) for those without (p = 0.039). The cumulative incidences of implant failure at 2 and 5 years were 2.1% (95% CI, 0-6.3) and 17.3% (95% CI, 0.7-33.9) for mechanical reasons and 6.4% (95% CI, 0-13.4) and 9.2% (95% CI, 0.5-17.9) for infection, respectively. Reasons for reconstruction failure were instability (n = 1 [2%]), loosening (n = 3 [6%]), and infection (n = 4 [9%]). Mean MSTS functional outcome score at followup was 70% (range, 33%-93%). At short-term followup, the LUMiC(A (R)) prosthesis demonstrated a low frequency of mechanical complications and failure when used to reconstruct the acetabulum in patients who underwent major pelvic tumor resections, and we believe this is a useful reconstruction for periacetabular resections for tumor or failed prior reconstructions. Still, infection and dislocation are relatively common after these complex reconstructions. Dual-mobility articulation in our experience is associated with a lower risk of dislocation. Future, larger studies will need to further control for factors such as dual-mobility articulation and silver coating. We will continue to follow our patients over the longer term to ascertain the role of this implant in this setting. Level IV, therapeutic study

    Pediatric drug safety signal detection: a new drug-event reference set for performance testing of data-mining methods and systems

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    BACKGROUND: Better evidence regarding drug safety in the pediatric population might be generated from existing data sources such as spontaneous reporting systems and electronic healthcare records. The Global Research in Paediatrics (GRiP)-Network of Excellence aims to develop pediatric-specific methods that can be applied to these data sources. A reference set of positive and negative drug-event associations is required. OBJECTIVE: The aim of this study was to develop a pediatric-specific reference set of positive and negative drug-event associations. METHODS: Considering user patterns and expert opinion, 16 drugs that are used in individuals aged 0-18 years were selected and evaluated against 16 events, regarded as important safety outcomes. A cross-table of unique drug-event pairs was created. Each pair was classified as potential positive or negative control based on information from the drug's Summary of Product Characteristics and Micromedex. If both information sources consistently listed the event as an adverse event, the combination was reviewed as potential positive control. If both did not, the combination was evaluated as potential negative control. Further evaluation was based on published literature. RESULTS: Selected drugs include ibuprofen, flucloxacillin, domperidone, methylphenidate, montelukast, quinine, and cyproterone/ethinylestradiol. Selected events include bullous eruption, aplastic anemia, ventricular arrhythmia, sudden death, acute kidney injury, psychosis, and seizure. Altogether, 256 unique combinations were reviewed, yielding 37 positive (17 with evidence from the pediatric population and 20 with evidence from adults only) and 90 negative control pairs, with the remainder being unclassifiable. CONCLUSION: We propose a drug-event reference set that can be used to compare different signal detection methods in the pediatric population

    Nanopatterning of Cu-Ligated Mercaptoalkanoic Acid Multilayers on Si Substrates via Atomic Force Lithography

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    Chemical self-assembly has garnered tremendous interest as a tool for generating nanometer-scale structures and devices. Organosilane self-assembled monolayers (SAMs) are of particular interest because of their ability to assemble on a wide range of substrates with varied chemical functionalities. Nanoshaving, an atomic force lithographic technique, has been demonstrated as a method to generate nanopatterns of organosilane SAMs. However, this method requires extremely high force setpoints, which rapidly dulls atomic force microscopy tips and degrades the resolution of the resulting nanopattern. In this work, we utilize Cu-ligated mercaptohexadecanoic acid (MHDA) multilayers to circumvent this limitation. Initially, a 10-undecenyltrichlorosilane (UTS) SAM is assembled onto a Si substrate, and the terminal olefin groups of the UTS SAM are oxidized to carboxyl groups. Subsequently, a Cu-ligated MHDA multilayer is assembled via the sequential deposition of Cu2+ ions and MHDA molecules. The interface between the oxidized UTS SAM and Cu-ligated MHDA multilayer serves as a natural low force breakpoint for nanoshaving. We demonstrate that the resulting nanopatterns can function as a chemical resist to fabricate metal nanostructures

    4.4 INTERACTIVE MODELING AND VISUALIZATION IN UNDERGRADUATE SURVEY COURSES

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    Over the past decade, the paradigm for undergraduate education has shifted in focus fro

    The Influence of Obesity on the Complication Rate and Outcome of Total Knee Arthroplasty A Meta-Analysis and Systematic Literature Review

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    Background: The increase in the number of individuals with an unhealthily high body weight is particularly relevant in the United States. Obesity (body mass index >= 30 kg/m(2)) is a well-documented risk factor for the development of osteoarthritis. Furthermore, an increased prevalence of total knee arthroplasty in obese individuals has been observed in the last decades. The primary aim of this systematic literature review was to determine whether obesity has a negative influence on outcome after primary total knee arthroplasty. Methods: A search of the literature was performed, and studies comparing the outcome of total knee arthroplasty in different weight groups were included. The methodology of the included studies was scored according to the Cochrane guidelines. Data extraction and pooling were performed. The weighted mean difference for continuous data and the weighted odds ratio for dichotomous variables were calculated. Heterogeneity was calculated with use of the 12 statistic. Results: After consensus was reached, twenty studies were included in the data analysis. The presence of any infection was reported in fourteen studies including 15,276 patients (I-2, 26%). Overall, infection occurred more often in obese patients, with an odds ratio of 1.90 (95% confidence interval [CI], 1.46 to 2.47). Deep infection requiring surgical debridement was reported in nine studies including 5061 patients (I-2, 0%). Deep infection occurred more often in obese patients, with an odds ratio of 2.38 (95% CI, 1.28 to 4.55). Revision of the total knee arthroplasty, defined as exchange or removal of the components for any reason, was documented in eleven studies including 12,101 patients (I-2, 25%). Revision for any reason occurred more often in obese patients, with an odds ratio of 1.30 (95% CI, 1.02 to 1.67). Conclusions: Obesity had a negative influence on outcome after total knee arthroplast

    Advanced Multimedia For Education On The Internet

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    INTRODUCTION Research in the education field has supported a shift toward learning in a constructivist setting, i.e., one in which the user actively learns about a topic through inquiry and exploration rather than passively receiving information [Ramamurthy 1999]. At the same time, the rapid increase in desktop computer capabilities coupled with a decrease in hardware cost has made possible the delivery and viewing of more advanced forms of multimedia content to the typical Internet user. Web developers and content providers have a variety of options available to add this content to their sites. These faster computers and new multimedia formats allow access to animation, video, and interactive diagrams that can give the student a much more intuitive feel for scientific concepts than traditional text and static 2-dimensional diagrams. 2. TECHNOLOGY The Java programming language from Sun Microsystems provides one method of including the non-trivial, interactive content necessary to

    Sarkad, Gyula, Békéscsaba 10. évfolyamos fiatalok életvitelének vizsgálata

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    Purpose: In order to identify challenges in pediatric pharmacoepidemiological safety studies, we assessed the characteristics of such (published) studies. Methods: Relevant articles from inception to 2013 were retrieved from Embase and Medline. We sequentially screened titles, abstracts and full texts with independent validation. We systematically collected data regarding general information, study methods and results. Results: Out of 4825 unique articles, 268 full texts (5.6%) were retained; 147 (54.9%) pertained to drugs rather than vaccines. Considering the 268 studies, 202 (75.4%) concerned children and adolescents (2 to 11 years) and 14 (5.3%) included preterm newborns. Most studies originated from North America (154 [57.5%]) or Europe (92 [34.3%]). Only 47 studies (17.5%) were privately funded. The majority (174 [64.9%]) were cohort studies. Out of 268 studies, 196 (73.1%) collected data retrospectively; paper medical charts were the most common data source for the exposures (85 [31.7%]) and outcomes (122 [45.5%]). Only 3 (2.0%) drug-only studies investigated rarely used drugs. Considering all 268 studies, only 27 (10.1%) reported sample size or power calculation. Most (75 [51.0%]) drug-only studies corrected confounding by multivariate modeling unlike stratification in 66 (55.9%) vaccine-only studies. Considering 75 child-only studies without any statistically significant result, 41 (54.7%) did not discuss lack of power. Conclusions: Although the field of pediatric pharmacoepidemiology is steadily developing evaluation seldom includes neonates, is mainly focused on few drug classes and safety outcomes and concerns mainly drug use in developed countries. Small study size is a specific challenge in pediatrics. Reporting should be improved. © 2016 The Authors. Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd

    6.14 1. BACKGROUND

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    Most of the best known and most extensive of the WWW servers that offer weather information products started as a single page listing and expanded from there to the detailed multi-page collections that they are today. Such was the case with the sections of the University of Illinois at Urbana-Champaign Department of Atmospheric Sciences ’ servers. Excluding the sections that offered educational material and the widely successful interactive weather map tools, the rest of the sections offering the bulk of the weather products however, unfortunately fell into disarray...victims of uncoordinated growth and the ultimately unmanageable underlying structures that supported them. So armed with experiences, successes, failures, and lots of wishlist items, we started out with a clean slate and undertook the design of a completely new weather server in order to “do it right this time.” The following details the design process and goals of the Weather World 2010 ™ server project. (Because much of the implementation of this design was still in progress (and flux) at the time of this writing, details of the actual implementation will be presented at a later date.

    Dynamics of the human gut microbiome in inflammatory bowel disease.

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    Inflammatory bowel disease (IBD) is characterized by flares of inflammation with a periodic need for increased medication and sometimes even surgery. The aetiology of IBD is partly attributed to a deregulated immune response to gut microbiome dysbiosis. Cross-sectional studies have revealed microbial signatures for different IBD subtypes, including ulcerative colitis, colonic Crohn's disease and ileal Crohn's disease. Although IBD is dynamic, microbiome studies have primarily focused on single time points or a few individuals. Here, we dissect the long-term dynamic behaviour of the gut microbiome in IBD and differentiate this from normal variation. Microbiomes of IBD subjects fluctuate more than those of healthy individuals, based on deviation from a newly defined healthy plane (HP). Ileal Crohn's disease subjects deviated most from the HP, especially subjects with surgical resection. Intriguingly, the microbiomes of some IBD subjects periodically visited the HP then deviated away from it. Inflammation was not directly correlated with distance to the healthy plane, but there was some correlation between observed dramatic fluctuations in the gut microbiome and intensified medication due to a flare of the disease. These results will help guide therapies that will redirect the gut microbiome towards a healthy state and maintain remission in IBD
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