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INTRODUCTION: Serum concentration of C-reactive protein (CRP) that exceeds a pre-defined threshold between the 3rd and 5th postoperative day is a reliable marker of infectious complications after colorectal surgery. However, the optimal strategy to follow when a high CRP is found has not been defined. The aim of this study was to analyze the usefulness of computed tomography (CT) scan in this situation in a prospective cohort of patients following colorectal surgery. METHODS: Between November 2011 and April 2015, patients at two surgical centers who had undergone elective colorectal resection with anastomosis and who had a CRP>12.5mg/dL on the 4th postoperative day (POD) were prospectively included in a database. Data were collected concerning all complications occurring during the 30days following surgery, method of diagnosis, management and clinical course. The decision to perform a CT scan between POD 4 and POD 6 day was guided only by the elevation of CRP in the absence of any other clinical signs; results were analyzed to evaluate the diagnostic value of elevated CRP. Uni- and multivariable analyses were performed to identify risk factors for postoperative infection. RESULTS: The study included a total of 174 patients: 56 (32.1%) had a CT between POD 4 and 6, and this helped detect a postoperative complication in 55.4% of cases. Patients who did not undergo CT had lower CRP values (16.3 vs. 18.5, P=0.02). Among the 118 patients who did not undergo CT, 50.8% eventually developed an infectious complication. The sensitivity of CRP-guided CT was 76.7% with a negative predictive value of 78.8%. CONCLUSION: If an elevated CRP is found on POD 4, an abdominopelvic CT should be performed. A normal result does not formally eliminate the existence of intra-abdominal complication. A study protocol should be set up to evaluate whether systematic revisional surgery or repeat CT scan is the appropriate management if CRP in the next two days reveals persistent inflammation.

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INTRODUCTION: Isolated hepatic perfusion allows the delivery of high dose chemotherapy while decreasing extra-hepatic toxicity, and is used mainly for patients with surgically unresectable liver tumors. PRINCIPLES: Vascular exclusion of the liver is performed after obtaining satisfactory hemodynamic tolerance, occasionally after cavocaval shunt and/or porto-systemic shunt. Perfusion entry can be arterial and/or portal while the exit is portal or caval. The perfusion circuit can be open or closed, using a circulation pump with or without oxygenation. The chemotherapy regimens used are high dose melphalan (with or without TNF-alpha), oxaliplatin, cisplatin and mitomycin, sometimes associated with moderate hyperthermia. The duration of perfusion ranges between 30 and 90 minutes according to the different protocols used. A percutaneous technique with incomplete liver vascular exclusion is also possible. RESULTS: The larger series in the literature show a response rate (partial or complete stabilization) between 60 and 80%, with approximately 5% complete morphologic responses. Morbidity and mortality are 40 and 5%, respectively, including specific morbidity related to the perfusion procedure as well as to chemotherapy. CONCLUSION: Chemotherapy delivered through isolated hepatic perfusion is a new therapeutic alternative, still under development, and can be proposed to patients with surgically unresectable primary or secondary liver tumors within clinical trials. These results seem to be promising, but are still associated with a non-negligible morbidity rate.

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We evaluated the clinical results and complications after extra-articular resection of the distal femur and/or proximal tibia and reconstruction with a tumour endoprosthesis (MUTARS) in 59 patients (mean age 33 years (11 to 74)) with malignant bone or soft-tissue tumours. According to a Kaplan-Meier analysis, limb survival was 76% (95% confidence interval (CI) 64.1 to 88.5) after a mean follow-up of 4.7 years (one month to 17 years). Peri-prosthetic infection was the most common indication for subsequent amputation (eight patients). Survival of the prosthesis without revision was 48% (95% CI 34.8 to 62.0) at two years and 25% (95% CI 11.1 to 39.9) at five years post-operatively. Failure of the prosthesis was due to deep infection in 22 patients (37%), aseptic loosening in ten patients (17%), and peri-prosthetic fracture in six patients (10%). Wear of the bearings made a minor revision necessary in 12 patients (20%). The mean Musculoskeletal Tumor Society score was 23 (10 to 29). An extensor lag > 10° was noted in ten patients (17%). These results suggest that limb salvage after extra-articular resection with a tumour prosthesis can achieve good functional results in most patients, although the rates of complications and subsequent amputation are higher than in patients treated with intra-articular resection.

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Optical simulation software based on the ray-tracing method offers easy and fast results in imaging optics. This method can also be applied in other fields of light propagation. For short distance communications, polymer optical fibers (POFs) are gradually gaining importance. This kind of fiber offers a larger core diameter, e.g., the step index POF features a core diameter of 980 µm. Consequently, POFs have a large number of modes (>3 million modes) in the visible range, and ray tracing could be used to simulate the propagation of light. This simulation method is applicable not only for the fiber itself but also for the key components of a complete POF network, e.g., couplers or other key elements of the transmission line. In this paper a demultiplexer designed and developed by means of ray tracing is presented. Compared to the classical optical design, requirements for optimal design differ particularly with regard to minimizing the insertion loss (IL). The basis of the presented key element is a WDM device using a Rowland spectrometer setup. In this approach the input fiber carries multiple wavelengths, which will be divided into multiple output fibers that transmit only one wavelength. To adapt the basic setup to POF, the guidance of light in this element has to be changed fundamentally. Here, a monolithic approach is presented with a blazed grating using an aspheric mirror to minimize most of the aberrations. In the simulations the POF is represented by an area light source, while the grating is analyzed for different orders and the highest possible efficiency. In general, the element should be designed in a way that it can be produced with a mass production technology like injection molding in order to offer a reasonable price. However, designing the elements with regard to injection molding leads to some inherent challenges. The microstructure of an optical grating and the thick-walled 3D molded parts both result in high demands on the injection molding process. This also requires complex machining of the molding tool. Therefore, different experiments are done to optimize the process parameter, find the best molding material, and find a suitable machining method for the molding tool. The paper will describe the development of the demultiplexer by means of ray-tracing simulations step by step. Also, the process steps and the realized solutions for the injection molding are described.

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The diagnosis and treatment of periprosthetic joint infections is a difficult situation for the attending physician. From the extensive literature, algorithms for diagnosis and therapy can be created. The aim of this study was to collect a representative survey of current concepts in the Federal States of the former West Germany and to compare them with those in the current literature. In 2011 orthopaedic and trauma clinics were surveyed anonymously in western Germany about diagnosis and treatment of periprosthetic infections. 450 questionnaires could be evaluated. Septic hip arthroplasty revisions were performed on average 12 (± 20)/year, septic knee arthroplasty revisions were performed on average 9 (± 17)/year. On average 205 (± 178) primary hip and 167 (± 155) primary knee arthroplasties were implanted/year. The analysis of the collected parameters is summarised in three tables. In the field of diagnostics, parameters such as CRP are determined. The interpretation, however, differs in more than 50 % of the hospitals on the relevant literature. Some important diagnostic parameters are not used. Therapy concepts are largely consistent with the literature. To a non-negligible extent, the vacuum-assisted therapy (approximately 30 % of hospitals) is used. In the literature it is described only for early infection. But even for use in early infection, there are very few data available. A unified diagnostic algorithm would be desirable.

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The management of a patient with a post-radiation pancreatitis is reported. Several biopsies and imaging failed to diagnose the radiation-induced carcinoma revealed during emergency laparotomy. This diagnosis must be kept in mind, and repeated biopsies are necessary.

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For years the Ilizarov fixator has been an established method for the treatment of orthopedic and trauma patients. The Taylor Spatial Frame is a software-navigated hexapod construction on the basis of the Ilizarov fixator. Unicompartmental arthroplasty of the knee is an option especially in medial osteoarthritis. The therapeutic procedure with a complicated development is illustrated by a case report on a patient with post-traumatic deformity of the femur and medial osteoarthritis of the knee.

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This article presents treatment priorities for open pelvic fracture and the results of 12 patients. In a retrospective study we analyzed 12 patients treated at a level 1 trauma center between 1994 and 1998 of whom eight were male and four female with an average age of 29.6 years. Six type C (6 x III degrees open) and six type B (4 x II degrees and 2 x III degrees open) were identified. On average, 15 EKs were necessary within the first 12 h of treatment (type C=17, type B=13). All type C fractures underwent emergency stabilization with the pelvic C-clamp. Early laparotomy was performed in 60%. Perineal laceration was identified in 58%, followed by nerve and plexus lesions in 42%, injuries of the genitourinary tract in 33%, and lesions of the fecal stream in 25%. Altogether, there were more peripelvic injuries associated with type C fracture than with type B (12 vs 8). On average, there were 27 second-look operations necessary with 3-.2 operations per patient. The average stay in the ICU was 82 days (80-360); 25% died. Control of hemorrhage is fundamental; therefore, emergency stabilization of the pelvis is essential followed by surgical procedures. Early surgical definitive stabilization of the fracture decreases septic complications. Such complex injuries should be treated at specialized trauma centers.

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Two questions were investigated: Do ankle devices have any influence on sports performance? Are there any differences between the devices? 31 participants could be included. The average age was 24.5 (+/- 4.1). The participants exercised 5.8 hours/week. We tested 41 ankles without any previous injury. With the Cybex 6000 four parameters were evaluated. Torque maximum for the plantarflexion, range of motion, work in Joule. The ankles were tested with three different ortheses, ankle taping and without any device. The Friedman Test was used to evaluate differences between the five test conditions. All measurements showed significant worse results for the devices and taping. The protective effect of ankle devices is well known. In this investigation we could show a restriction of the performance. Thus it should be decided individually, if an ankle device is useful.

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Annealing of commercial grade cadmium phosphide (CD3P2) at 600 K produces a material which, in magic-angle spinning spin-lattice 31P NMR relaxation experiments, has broad lines and multiple T1 values. By contrast, sublimation at 900 K results in a crystalline material with narrow lines and a single T1. However, both materials have the same Cd-P lattice spacings as determined by rotational-echo, double-resonance 31P NMR with 113Cd dephasing. Both materials also have closely similar X-ray diffraction powder patterns. These results are interpreted in terms of a distribution of lattice vacancies in the annealed material, creating structural heterogeneity but with no substantial change in lattice parameters from those of the sublimed cadmium phosphide.

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Structural constraints for the tryptophans in rat cellular retinol binding protein II (CRBP II) have been obtained by rotational-echo double-resonance (REDOR) solid-state NMR. CRBP II was labeled with L-[6-19F]tryptophan and L-[2-13C]tryptophan. The 13C-19F dipolar coupling was determined for various possible tryptophan geometries. The allowed distance between the closest two of the four tryptophans in CRBP II was obtained for each geometry. The minimum possible distance between these two tryptophans in CRBP II is 7 A, and the maximum possible distance is 11 A.

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Solid-state 13C and 15N NMR spectra have been obtained of intact adhesive plaques from the mussel Geukensia demissa labeled by L-[6-13C,6-15N]lysine. The plaques are rich in a polyphenolic protein glue which has 50 or more repeats of a nonapeptide sequence with one lysine per repeat. The average isotopic 15N enrichment of lysyl epsilon nitrogens in the plaques was 4%. These lysyl amines are not involved in ionic complexes and do not form observable concentrations of covalent crosslinks.

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Cross-polarization, magic-angle spinning 13C NMR spectra of skeletal components of individual colonies of the New Zealand black coral, Antipathes fiordensis, have a marked similarity to spectra of the sclerotized exoskeleton of the adult tobacco hornworm, Manduca sexta. NMR analysis estimates the organic content of the load-bearing skeletal base of A. fiordensis as 70% protein, 10% chitin, 15% diphenol, and 5% lipid by weight, and that of M. Sexta moth cuticle as 60% protein, 20% chitin, 15% diphenol, and 5% lipid. The younger pinnules or tips of A. fiordensis are less than 3% diphenol by weight. The only diphenols extracted from coral skeleton by hydrochloric acid are 3-(3,4-dihydroxyphenyl)-DL-alanine (DOPA) and 3,4-dihydroxybenzaldehyde (DOBAL), while the predominant diphenols in acid extracts of insect cuticles are N-acyldopamines. More DOPA is found in the base than in the tips of A. fiordensis and it appears to be a peptidyl component of coral skeletal protein. The oxidation of DOPA and DOBAL to quinones may provide mechanical stabilization of the coral skeleton by cross-linking of structural proteins to other proteins or to chitin.

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This study evaluated an open access general practitioner radiological service. Questionnaires were completed in 216 out of 250 cases both before and after radiological examination. Chests and specials (bariums, intravenous urography, ultrasound) were most often of diagnostic value when confirming normality, while other radiographs were more likely to be of value in assessing the severity of known disease (P less than 0.001). Patient therapy was altered in 31% of cases following receipt of the radiological report, and management was changed in 40%. In 25% of cases the patient was discharged on receipt of the report. In 28% of cases the report avoided a hospital referral. Special examinations were most likely (P less than 0.05) to avoid a referral. It is concluded that open access radiology is a considerable help with diagnosis and management, and substantially reduces out-patient referrals. The possible consequences for the acute services of providing a full general practitioner diagnostic service are discussed.

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