942 resultados para polyester prosthesis


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Segment poses and joint kinematics estimated from skin markers are highly affected by soft tissue artifact (STA) and its rigid motion component (STARM). While four marker-clusters could decrease the STA non-rigid motion during gait activity, other data, such as marker location or STARM patterns, would be crucial to compensate for STA in clinical gait analysis. The present study proposed 1) to devise a comprehensive average map illustrating the spatial distribution of STA for the lower limb during treadmill gait and 2) to analyze STARM from four marker-clusters assigned to areas extracted from spatial distribution. All experiments were realized using a stereophotogrammetric system to track the skin markers and a bi-plane fluoroscopic system to track the knee prosthesis. Computation of the spatial distribution of STA was realized on 19 subjects using 80 markers apposed on the lower limb. Three different areas were extracted from the distribution map of the thigh. The marker displacement reached a maximum of 24.9mm and 15.3mm in the proximal areas of thigh and shank, respectively. STARM was larger on thigh than the shank with RMS error in cluster orientations between 1.2° and 8.1°. The translation RMS errors were also large (3.0mm to 16.2mm). No marker-cluster correctly compensated for STARM. However, the coefficient of multiple correlations exhibited excellent scores between skin and bone kinematics, as well as for STARM between subjects. These correlations highlight dependencies between STARM and the kinematic components. This study provides new insights for modeling STARM for gait activity.

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Objectives: The growing interest in minimally invasive surgery, together with the possibility of fitting prostheses with immediate function, have led to the development of software capable of planning and manufacturing a surgical guide and prosthesis that can be placed upon conclusion of the implant surgery step. The present study evaluates the surgical and prosthetic complications of implant treatment with the guided surgery technique, together with patient comfort during and after treatment. Patients and methods: A retrospective observational study was made of 19 patients with partially or totally edentulous upper and/or lower maxillae, involving the placement of a total of 122 implants. All cases were planned and operated upon with the guided surgery technique. Results: A total of 122 implants were placed in 14 males and 5 females. The intraoperative surgical complications comprised a lack of primary stability, while the postoperative complications consisted of infections and a lack of implant osteointegration. Ten implants failed. The prosthetic complications in turn comprised loosening of the provisional prosthesis screws, prosthesis tooth fracture, and a lack of passive fit of the immediate prosthesis. The degree of patient satisfaction was evaluated using a verbal scale. Conclusions: Implant restoration with the guided surgery technique and immediate functional loading is a predictable procedure, provided patient selection and the surgical technique are adequate, affording lesser postoperative morbidity and increased patient satisfaction thanks to the immediate restoration of esthetics and function

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The cuticle is an essential diffusion barrier on aerial surfaces of land plants whose structural component is the polyester cutin. The PERMEABLE CUTICLE1/ABCG32 (PEC1) transporter is involved in plant cuticle formation in Arabidopsis. The gpat6 pec1 and gpat4 gapt8 pec1 double and triple mutants are characterized. Their PEC1-specific contributions to aliphatic cutin composition and cuticle formation during plant development are revealed by gas chromatography/mass spectrometry and Fourier-transform infrared spectroscopy. The composition of cutin changes during rosette leaf expansion in Arabidopsis. C16:0 monomers are in higher abundance in expanding than in fully expanded leaves. The atypical cutin monomer C18:2 dicarboxylic acid is more prominent in fully expanded leaves. Findings point to differences in the regulation of several pathways of cutin precursor synthesis. PEC1 plays an essential role during expansion of the rosette leaf cuticle. The reduction of C16 monomers in the pec1 mutant during leaf expansion is unlikely to cause permeability of the leaf cuticle because the gpat6 mutant with even fewer C16:0 monomers forms a functional rosette leaf cuticle at all stages of development. PEC1/ABCG32 transport activity affects cutin composition and cuticle structure in a specific and non-redundant fashion.

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Different therapeutic options for prosthetic joint infections exist, but surgery remains the key. With a two-stage exchange procedure, a success rate above 90% can be expected. Currently, there is no consensus regarding the optimal duration between explantation and the reimplantation in a two-stage procedure. The aim of this study was to retrospectively compare treatment outcomes between short-interval and long-interval two-stage exchanges. Patients having a two-stage exchange of a hip or knee prosthetic joint infection at Lausanne University Hospital (Switzerland) between 1999 and 2013 were included. The satisfaction of the patient, the function of the articulation and the eradication of infection, were compared between patients having a short (2 to 4 weeks) versus a long (4 weeks and more) interval during a two-stage procedure. Patient satisfaction was defined as good if the patient did not have pain and bad if the patient had pain. Functional outcome was defined good if the patient had a prosthesis in place and could walk, medium if the prosthesis was in place but the patient could not walk, and bad if the prosthesis was no longer in place. Infection outcome was considered good if there had been no re-infection and bad if there had been a re-infection of the prosthesis 145 patients (100 hips, 45 knees) were identified with a median age of 68 years (range 19-103). The median hospital stay was 58 days (range 10-402). The median follow-up was 12.9 months (range 0.5-152). 28 % and 72 % of the patients had a short-interval and long-interval exchange of the prosthesis, respectively. Patient satisfaction, functional outcome and infection outcome for patients having a short versus a long interval are reported in the Table. The patient satisfaction was higher when a long interval was performed whereas the functional and infection outcomes were higher when a short interval was performed. According to this study a short-interval exchange appears preferable to a long interval, especially in the view of treatment effectiveness and functional outcome.

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Concomitant aortic and mitral valve replacement or concomitant aortic valve replacement and mitral repair can be a challenge for the cardiac surgeon: in particular, because of their structure and design, two bioprosthetic heart valves or an aortic valve prosthesis and a rigid mitral ring can interfere at the level of the mitroaortic junction. Therefore, when a mitral bioprosthesis or a rigid mitral ring is already in place and a surgical aortic valve replacement becomes necessary, or when older high-risk patients require concomitant mitral and aortic procedures, the new 'fast-implantable' aortic valve system (Intuity valve, Edwards Lifesciences, Irvine, CA, USA) can represent a smart alternative to standard aortic bioprosthesis. Unfortunately, this is still controversial (risk of interference). However, transcatheter aortic valve replacements have been performed in patients with previously implanted mitral valves or mitral rings. Interestingly, we learned that there is no interference (or not significant interference) among the standard valve and the stent valve. Consequently, we can assume that a fast-implantable valve can also be safely placed next to a biological mitral valve or next to a rigid mitral ring without risks of distortion, malpositioning, high gradient or paravalvular leak. This paper describes two cases: a concomitant Intuity aortic valve and bioprosthetic mitral valve implantation and a concomitant Intuity aortic valve and mitral ring implantation.

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Aortic root (AoR) components provide synchronous and precise 3D deformation of the aortic root during the cardiac cycle in order to ensure closure and opening of the three leaflets over a lifetime. Any deviation from the natural 3D morphology, such as with AoR annulus dilatation, enlarged sinuses and/or dilatation of the sinotubular junction, as in the case of ascending aortic dilatation, may result in disruption of the natural AoR function. Surgical treatment of AoR pathology has two modalities: the replacement of the aortic valve by artificial prosthesis or by preservation of the three leaflets and reconstruction of the aortic root components. Currently, there are two basic aortic root reconstruction procedures: aortic root sparing and aortic valve reimplantation techniques. Regardless of the technique used, the restoration of adequate cusp coaptation, is from a technical point of view, the most important element to consider. To achieve this, there are two requirements that need to be met: (i) the valve coaptation should be superior to the level of the aortic root base by at least 8 mm and (ii) the coaptation height per se has to be ≥5 mm. Successful restoration of the aortic root requires adequate technical skills, detailed knowledge of aortic root anatomy and topography, and also knowledge of the spatial pattern of AoR elements. Recently, there has been growing interest in aortic root reconstructive procedures as well their modifications. As such, the aim of this review is to analyse aortic root topography and 3D anatomy from a surgical point of view. The review also focuses on potential risk regions that one should be aware of before the surgical journey into the 'deep waters area' of the AoR begins.

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The authors report the case of a giant cell tumor of the frontal sinus in a 54-year-old male patient. This tumor location is rare, and this is the third case reported in the literature with radiographic documentation and histopathological confirmation. The patient underwent surgery, with curettage of frontal sinus and placement of a prosthesis. He died because a voluntary abrupt discontinuation of corticosteroids.

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Objective To evaluate the association of conventional angiography (AG) with computed tomography angiography (CTA) as compared with CTA only, preoperatively, in the treatment of aortic diseases. Materials and Methods Retrospective study involving patients submitted to endovascular treatment of aortic diseases, in the period from January 2009 to July 2010, with use of preoperative CTA + conventional AG or CTA only. The patients were divided into two groups, namely: G1 – thoracic aortic diseases; and G2 – abdominal aortic diseases. G1 was subdivided into 1A (preoperative AG + CTA) and 1B (preoperative CTA). G2 was subdivided into 2C (CTA + AG) and 2D (CTA only). Results The authors evaluated 156 patients. In subgroups 1A and 1B, the rate of technical success was, respectively, 100% and 94.7% (p = 1.0); and the rate of therapeutic success was, respectively, 81% and 58% (p = 0.13). A higher number of complications were observed in subgroup 1B (p = 0.057). The accuracy in the calculation of the prosthesis was higher in subgroup 1A (p = 0.065). In their turn, the rate of technical success in subgroups 2C and 2D was, respectively, 92.3% and 98.6% (p = 0.17). The rate of therapeutic success was 73% and 98.6% (p = 0.79). Conclusion Preoperative conventional AG should be reserved for cases where CTA cannot provide all the information in the planning of a therapeutic intervention.

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Cleidocranial dysostosis is a rare genetic syndrome with an autosomal dominant inheritance pattern. The most common manifestations include clavicular aplasia or hypoplasia, open fontanelles and abnormal dentition. The present report describes two familial cases whose late diagnosis was made by means of clinical and radiographic findings. The treatment was radical, with complete surgical teeth extraction and making of total dental prosthesis.

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This study aimed at comparing the efficiency of various sampling materials for the collection and subsequent analysis of organic gunshot residues (OGSR). To the best of our knowledge, it is the first time that sampling devices were investigated in detail for further quantitation of OGSR by LC-MS. Seven sampling materials, namely two "swab"-type and five "stub"-type collection materials, were tested. The investigation started with the development of a simple and robust LC-MS method able to separate and quantify molecules typically found in gunpowders, such as diphenylamine or ethylcentralite. The evaluation of sampling materials was then systematically carried out by first analysing blank extracts of the materials to check for potential interferences and determining matrix effects. Based on these results, the best four materials, namely cotton buds, polyester swabs, a tape from 3M and PTFE were compared in terms of collection efficiency during shooting experiments using a set of 9 mm Luger ammunition. It was found that the tape was capable of recovering the highest amounts of OGSR. As tape-lifting is the technique currently used in routine for inorganic GSR, OGSR analysis might be implemented without modifying IGSR sampling and analysis procedure.

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AbstractObjective:To define the distal femur rotation pattern in a Brazilian population, correlating such pattern with the one suggested by the arthroplasty instruments, and analyzing the variability of each anatomic parameter.Materials and Methods:A series of 101 magnetic resonance imaging studies were evaluated in the period between April and June 2012. The epidemiological data collection was performed with the aid of the institution's computed imaging system, and the sample included 52 male and 49 female patients. The measurements were made in the axial plane, with subsequent correlation and triangulation with the other plans. The posterior condylar line was used as a reference for angle measurements. Subsequently, the anatomical and surgical transepicondylar axes and the anteroposterior trochlear line were specified. The angles between the reference line and the studied lines were calculated with the aid of the institution's software.Results:The mean angle between the anatomical transepicondylar axis and the posterior condylar line was found to be 6.89°, ranging from 0.25° to 12°. For the surgical transepicondylar axis, the mean value was 2.89°, ranging from –2.23° (internal rotation) to 7.86°, and for the axis perpendicular to the anteroposterior trochlear line, the mean value was 4.77°, ranging from –2.09° to 12.2°.Conclusion:The anatomical transepicondylar angle showed mean values corresponding to the measurement observed in the Caucasian population. The utilized instruments are appropriate, but no anatomical parameter proved to be steady enough to be used in isolation.

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We report a case of ascending aortic graft infection by an atypical bacteria, Mycoplasma hominis, with mediastinitis, a dreaded complication after cardiac surgery. A 55-year-old patient underwent ascending aorta replacement for acute type A dissection. He developed sternal instability and purulent discharge, requiring sternal wire removal and debridement. Cultures were initially sterile, but showed M. hominis infection after a significant delay and in specific culture media. The patient was treated with doxycycline and moxifloxacine. Cultures became negative and the sternum was closed on the 28th postoperative day after the first debridement. Recovery was favorable, with no signs of infection. Antibiotics were continued for one year. The patient is still asymptomatic 16 months after antibiotic interruption. Atypical organisms should be considered in the differential diagnosis of acute mediastinitis of unknown etiology after routine microbiological investigations.

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Since routine eubacterial 16S rRNA PCR does not amplify members of the Chlamydiales order, we tested all samples received in our laboratory during a 10 months period using a pan-Chlamydiales real-time PCR. 3 of 107 samples (2.8%) revealed to be positive, suggesting a role of some Chlamydiales in the pathogenesis of chronic bronchial stenosis or bronchial stenosis superinfection and as agents of orthopaedic prosthesis infections.

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A flow injection spectrophotometric method was developed for determining aspartame in sweeteners. Sample was dissolved in water and 250 µL of the solution was injected into a carrier stream of 5.0 x 10-5 mol L-1 sodium borate solution. The sample flowed through a column (14 cm x 2.0 mm) packed with Zn3(PO4)2 immobilized in a polymeric matrix of polyester resin and Zn(II) ions were released from the solid-phase reactor by formation of the Zn(II)-aspartame complex. The mixture merged with a stream of borate buffer solution (pH 9.0) containing 0.030 % (m/v) alizarin red S and the Zn(II)-alizarin red complex formed was measured spectrophotometrically at 540 nm. The calibration graph for aspartame was linear in the concentration range from 10 to 80 µg mL-1 with a detection limit of 4 µg mL-1 of aspartame. The RSD was 0.3 % for a solution containing 40 µg mL-1 aspartame (n = 10) and seventy results were obtained per hour. The proposed method was applied for determining aspartame in commercial sweeteners.

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This thesis focuses on fibre coalescers whose efficiency is based on the surface properties/characteristics. They have the ability to preferentially wet or interact with one or more of the fluids to be separated. Thus, the interfacial phenomena governing the separation efficiency of the coalescers is investigated depending on physical factors such as flowrates, phase ratios and coalescer packing density. Design of process equipment to produce and separate of the emulsions was carried out.The experimentation was carried out to test the separation efficiency of the coalescing medias, namely fibreglass, polyester I and polyester II. The performances of the coalescing medias were assessed via droplet size information. In conclusion, the objectives (design of process equipment and experimentation) were achieved. Fibre glass was the best coalescing media, next was polyester I and then finally polyester II. Droplets sizes increased with decreased flowrates and increased packing density of the coalescer. Phase ratio had effect on the droplet sizes of the feed but had no effect on the coalescence of droplets of the feed.