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51.
Pierre Kunz Paul Mick Sascha Gross Gerhard Schmidmaier Felix Zeifang Marc-André Weber Christian Fischer 《Journal of orthopaedic research》2020,38(5):1150-1158
Supraspinatus (SSP) tendon tears represent a common indication for shoulder surgery. Yet, prediction of postoperative function and tendon retear remains challenging and primarily relies on morphologic magnetic resonance imaging (MRI)-based parameters, supported by patients' demographic data like age, gender, and comorbidities. Considering continuously high retear rates, especially in patients with larger tears and negative prognostic factors, improved outcome prediction could be of high clinical value. Contrast-enhanced ultrasound (CEUS) enables an assessment of dynamic perfusion of the SSP muscle. As a potential surrogate for muscle vitality, CEUS might reflect functional properties of the SSP and support improved outcome prediction after tendon repair. Fifty patients with isolated SSP tendon tears were prospectively enrolled. Preoperatively, SSP muscle perfusion was quantified by CEUS and conventional morphologic parameters like tear size, fatty infiltration, and tendon retraction were assessed by MRI. At six months follow-up, shoulder function, tendon integrity, and muscle perfusion were reassessed. The predictive value of preoperative CEUS for postoperative shoulder function and tendon integrity was evaluated. 35 patients entered the statistical analysis. Preoperative CEUS-based assessment of SSP perfusion significantly correlated with early postoperative shoulder function (Constant, r = 0.48, p < 0.018) and tendon retear (r = 0.67, p < 0.001). CEUS-based subgroup analysis identified patients with exceptionally high, respectively low risk for tendon retear. CEUS-based assessment of the SSP seemed to predict early shoulder function and tendon retear after SSP repair and allowed to identify patient subgroups with exceptionally high or low risk for tendon retear. © 2019 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 38:1150-1158, 2020 相似文献
52.
Max J. Friedrich Jan Schmolders Robert D. Michel Thomas M. Randau Matthias D. Wimmer Hendrik Kohlhof Dieter C. Wirtz Sascha Gravius 《International orthopaedics》2014,38(12):2455-2461
Purpose
Revision of failed total hip arthroplasty with massive acetabular bone loss resulting in pelvic discontinuity represents a rare but challenging problem. The objective of this study was to present short to mid-term results of revision total hip arthroplasty with a custom-made acetabular implant in a consecutive series of patients with pelvic discontinuity.Methods
We retrospectively reviewed 18 consecutive patients with massive acetabular bone loss (Paprosky Type 3B) resulting in pelvic discontinuity reconstructed with revision total hip arthroplasty using a custom-made acetabular component. The prosthesis was created on the basis of a thin-cut 1-mm computed tomography (CT) scan of the pelvis. Initial stability of the implant was obtained by screw fixation. Harris hip score and sequential radiographs were used to evaluate the clinical and radiographic results.Results
At an average follow up of 30 months (range 17–62 months) 16 of 18 (88.9 %) custom-made implants were considered radiographically stable without signs of acetabular migration of more than 2 mm in the horizontal or vertical direction, implant rotation or screw breakage. Complications included two periprosthetic joint infections treated with explantation of the implant. Three patients had recurrent dislocations postoperatively. The mean Harris hip score improved from 28?±?12 points preoperatively to 69?±?13 points at the time of last follow up.Conclusion
Treatment of acetabular bone loss and pelvic discontinuity with a custom-made acetabular component can provide a durable solution with good clinical and radiographic results. 相似文献53.
Willemien van den Bos Berrend G. Muller Hashim Ahmed Chris H. Bangma Eric Barret Sebastien Crouzet Scott E. Eggener Inderbir S. Gill Steven Joniau Gyoergy Kovacs Sascha Pahernik Jean J. de la Rosette Olivier Rouvière Georg Salomon John F. Ward Peter T. Scardino 《European urology》2014
Background
Focal therapy has been introduced for the treatment of localised prostate cancer (PCa). To provide the necessary data for consistent assessment, all focal therapy trials should be performed according to uniform, systematic pre- and post-treatment evaluation with well-defined end points and strict inclusion and exclusion criteria.Objective
To obtain consensus on trial design for focal therapy in PCa.Design, setting, and participants
A four-staged consensus project based on a modified Delphi process was conducted in which 48 experts in focal therapy of PCa participated. According to this formal consensus-building method, participants were asked to fill out an iterative sequence of questionnaires to collect data on trial design. Subsequently, a consensus meeting was held in which 13 panellists discussed acquired data, clarified the results, and defined the conclusions.Outcome measurements and statistical analysis
A multidisciplinary board from oncologic centres worldwide reached consensus on patient selection, pretreatment assessment, evaluation of outcome, and follow-up.Results and limitations
Inclusion criteria for candidates in focal therapy trials are patients with prostate-specific antigen <15 ng/ml, clinical stage T1c–T2a, Gleason score 3 + 3 or 3 + 4, life expectancy of >10 yr, and any prostate volume. The optimal biopsy strategy includes transrectal ultrasound-guided biopsies to be taken between 6 mo and 12 mo after treatment. The primary objective should be focal ablation of clinically significant disease with negative biopsies at 12 mo after treatment as the primary end point.Conclusions
This consensus report provides a standard for designing a feasible focal therapy trial.Patient summary
A variety of ablative technologies have been introduced and applied in a focal manner for the treatment of prostate cancer (PCa). In this consensus report, an international panel of experts in the field of PCa determined pre- and post-treatment work-up for focal therapy research. 相似文献54.
Sascha A. Müller MD Arianeb Mehrabi MD Nuh N. Rahbari MD Rene Warschkow MD Heike Elbers MD Christine Leowardi MD Hamidreza Fonouni MD Ignazio Tarantino MD MSc Peter Schemmer MD Bruno M. Schmied MD Markus W. Büchler MD 《Annals of surgical oncology》2014,21(1):155-164
Purpose
To assess the impact of perioperative blood transfusion on overall and disease-free survival in patients undergoing curative resection for cholangiocarcinoma.Methods
In a single-center study, 128 patients undergoing curative resection for cholangiocarcinoma between 2001 and 2010 were assessed. The median follow-up period was 19 months. Transfused and nontransfused patients were compared by Cox regression and propensity score analyses.Results
Overall, 38 patients (29.7 %) received blood transfusions. The patient characteristics were highly biased with respect to receiving transfusions (propensity score 0.69 ± 0.22 vs. 0.11 ± 0.16, p < 0.001). In the unadjusted analysis, blood transfusion was associated with a 105 % increased risk of mortality [hazard ratio (HR) 2.05, 95 % CI 1.19–3.51, p = 0.010]. In the multivariate (HR 1.14, 95 % CI 0.52–2.48, p = 0.745) and the propensity score-adjusted Cox regression (HR 1.02, 95 % CI 0.39–2.62, p = 0.974), blood transfusion had no influence on overall survival. Similarly, in the propensity score-adjusted Cox regression (HR 0.62, 95 % CI 0.24–1.58, p = 0.295), no relevant effect of blood transfusion on disease-free survival was observed.Conclusions
To our knowledge, this is the first propensity score-based analysis providing compelling evidence that the worse oncological outcome after curative resection for advanced cholangiocarcinoma in patients receiving perioperative blood transfusions is caused by the clinical circumstances requiring the transfusions, not by the blood transfusions themselves. 相似文献55.
Jens Hansen Marco Bianchi Maxine Sun Michael Rink Fabio Castiglione Firas Abdollah Thomas Steuber Sascha A. Ahyai Stefan Steurer Cosima Göbel Massimo Freschi Francesco Montorsi Shahrokh F. Shariat Margit Fisch Markus Graefen Pierre I. Karakiewicz Alberto Briganti Felix K.‐H. Chun 《BJU international》2014,113(3):399-407
56.
Heike M. A. Ehmann Sascha Winter Thomas Griesser Roman Keimel Simone Schrank Andreas Zimmer Oliver Werzer 《Pharmaceutical research》2014,31(10):2708-2715
Purpose
The low aqueous solubility of many drugs impedes detailed investigation as the detection limit of standard testing routines is limited. This is further complicated within application relevant thin films typical used in patches or stripes for buccal or topical routes.Methods
In this work a model system is developed based on spin – casting technique allowing defined clotrimazole and clotrimazole – polystyrene composite films preparation at a solid surface. Various highly sensitive techniques including quarz crystal microbalance (QCM), X-ray reflevtivity (XRR) and X-ray photon spectroscopy (XPS) are used to investigate the drug release over time into an aqueous media.Results
The results reveal a steady drug release for both samples over the course of the experiments but with the release from the composite being significantly slower. In addition the dissolution rate of the clotrimazole sample initially increases up to 30 min after which a decrease is noted. XRR shows that this is a result of surface roughening together with film thickness reduction. The results for the composite show that the release in the composite film is a result of drug diffusion within the matrix and collapsing PS film thickness whereby XPS shows that the amount of clotrimazole at the surface after 800 min immersion is still high.Conclusion
It can be stated that the applied techniques allow following low mass drug release in detail which may also be applied to other systems like pellets or surface loaded nano-carriers providing information for processing and application relevant parameters. 相似文献57.
Sascha Dietrich Olga Lykhachova Xiaoyin Cheng Michael Godehardt Markus Kronenberger Michael Meyer David Neusius Julia Orlik Katja Schladitz Haiko Schulz Konrad Steiner Diana Voigt 《Materials》2021,14(8)
Simulation-based prediction of mechanical properties is highly desirable for optimal choice and treatment of leather. Nowadays, this is state-of-the-art for many man-made materials. For the natural material leather, this task is however much more demanding due to the leather’s high variability and its extremely intricate structure. Here, essential geometric features of the leather’s meso-scale are derived from 3D images obtained by micro-computed tomography and subsumed in a parameterizable structural model. That is, the fiber-bundle structure is modeled. The structure model is combined with bundle properties derived from tensile tests. Then the effective leather visco-elastic properties are simulated numerically in the finite element representation of the bundle structure model with sliding contacts between bundles. The simulation results are validated experimentally for two animal types, several tanning procedures, and varying sample positions within the hide. Finally, a complete workflow for assessing leather quality by multi-scale simulation of elastic and visco-elastic properties is established and validated. 相似文献
58.
Pini Pietro Colombari Bruna Marchi Enrico Castagnoli Anna Venturelli Claudia Sarti Mario Blasi Elisabetta 《Diagnostic microbiology and infectious disease》2019,93(1):39-43
Invasive candidiasis (IC) plays an important role as severe infection. Elder population, immunocompromised individuals, and intensive care unit (ICU) patients, especially when exposed to major surgery, are the most affected. IC diagnosis and treatment are difficult because of the absence of pathognomonic signs and symptoms. In addition, culture-based examination (gold standard) is known to have low sensitivity and long time to report. All these often lead to unnecessary and costly empirical antifungal therapies, burdened also by the onset of drug resistance and serious side effects for the patient. To partially overcome these problems, in recent years, novel noncultural markers have been investigated with the aim of easily and rapidly achieving an early diagnosis of IC. Such novel markers include the pan-fungal antigen (1?→?3)-β-D-glucan (BDG) and the anti–Candida albicans germ tube antibodies (CAGTAs). We retrospectively analyzed the presence of CAGTA on ?80?°C stored serum samples, where the level of BDG had been previously assessed in a prospective study conducted in the Azienda Ospedaliero–Universitaria Policlinic of Modena (Pini et al. Infection 44:223–233, 2016). In particular, we selected 29 samples from proven IC episodes and 28 from non-IC cases. The 29 IC samples had been diagnosed as infections by C. albicans (n?=?16), C. glabrata (n?=?8), C. parapsilosis (n?=?1), C. pelliculosa (n?=?1), and C. tropicalis (n?=?1), while 2 samples had intrasurgery biopsies positive for yeast (compatible with Candida spp.). The 28 control samples (non-IC) included 9 sera with positive blood cultures [E. faecium (n?=?5), S. pneumoniae (n?=?2), P. aeruginosa?+?A. baumannii (n?=?2)] and 19 negative blood cultures. The CAGTA immunofluorescence assay was performed using 1:40, 1:80, 1:160, and 1:320 dilutions (reference dilution, as indicated by the manufacturer). According to the protocol, the samples were evaluated by the operator-dependent optical reading based on immunofluorescence positive/negative samples. In parallel, with the aim of standardizing the reading, the fluorescence images were captured, and the data were expressed as arbitrary fluorescence units (AFU). Finally, the results were interpreted as positive or negative using a cutoff provided by receiver operating characteristic (ROC) curves (Youden index). The traditional operator-dependent optical reading and the AFU measuring protocol provided comparable information with respect to the processed samples since IC and non-IC sera were correctly identified by the 2 CAGTA reading strategies in most of the cases. Interestingly, the AFU reading enabled a semiquantitative evaluation of the samples and an objective interpretation of the results. Based on the cutoff value, the AFU-based CAGTA procedure demonstrated a sensitivity of 52% and a specificity of 89%, while BDG showed a sensitivity of 90% and a specificity of 75%; the overall accuracy was 70% and 83% for CAGTA and BDG, respectively. The association of the 2 markers greatly increased both sensitivity and accuracy to 97% and 84%, respectively. As expected, when excluding non–C. albicans episodes, the sensitivity of CAGTA increased from 52% to 86%; moreover, with the exclusion of the non–deep-seated episodes, the sensitivity of CAGTA increased to 67% and reached 100% for C. albicans deep-seated candidiasis. Finally, when evaluating the influence of colonization, BDG demonstrated the most drastic decrease in specificity that dropped from 88% in noncolonized to 58% in colonized patients. With the exception of non–C. albicans episodes, CAGTA is a good marker of IC, particularly in the presence of deep-seated candidiasis. The performance of CAGTA greatly increases when used in combination with BDG. 相似文献
59.
60.
Sascha Dietrich Jürgen G. Okun Kathrin Schmidt Christine S. Falk Andreas H. Wagner Suzan Karamustafa Aleksandar Radujkovic Ute Hegenbart Anthony D. Ho Peter Dreger Thomas Luft 《Haematologica》2014,99(3):541-547
Steroid-refractory graft-versus-host disease is a life-threatening complication after allogeneic stem cell transplantation. Evidence is accumulating that steroid-refractory graft-versus-host disease is associated with endothelial distress. Endothelial cell homeostasis is regulated by nitric oxide, and serum nitrates are derived from nitric oxide synthase activity or dietary sources. In this retrospective study based on 417 patients allografted at our institution we investigated whether quantification of serum nitrates could predict steroid-refractory graft-versus-host disease. Elevated pre-transplant levels of serum nitrates (>26.5 μM) predicted steroid-refractory graft-versus-host disease (P=0.026) and non-relapse mortality (P=0.028), particularly in combination with high pre-transplant angiopoietin-2 levels (P=0.0007 and P=0.021, respectively). Multivariate analyses confirmed serum nitrates as independent predictors of steroid-refractory graft-versus-host disease and non-relapse mortality. Differences in serum nitrate levels did not correlate with serum levels of tumor necrosis factor or C-reactive protein or expression of inducible nitric oxide synthase in blood cells. Patients with high pre-transplant nitrate levels had significantly reduced rates of refractory graft-versus-host disease (P=0.031) when pravastatin was taken. In summary, patients at high risk of developing steroid-refractory graft-versus-host disease could be identified prior to transplantation by serum markers linked to endothelial cell function. Retrospectively, statin medication was associated with a reduced incidence of refractory graft-versus-host disease in this endothelial high-risk cohort. 相似文献