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41.
Cathérine Ruther Carolin Gabler Hartmut Ewald Martin Ellenrieder Maximilian Haenle Tobias Lindner Wolfram Mittelmeier Rainer Bader Daniel Kluess 《Journal of orthopaedic research》2014,32(4):606-612
Implant osseointegration can currently only be assessed reliably post mortem. A novel method that relies on the principle of acoustic sound analysis was developed to enable examination of the longitudinal progress of osseointegration. The method is based on a magnetic sphere inside a hollow cylinder of the implant. By excitation using an external magnetic field, collision of the sphere inside the implant produces a sound signal. Custom‐made titanium implants equipped thusly were inserted in each lateral femoral epicondyle of 20 New Zealand White Rabbits. Two groups were investigated: Uncoated, machined surface versus antiadhesive surface; and calcium phosphate‐coated surface versus antiadhesive surface. The sound analysis was performed postoperatively and weekly. After 4 weeks, the animals were euthanized, and the axial pull‐out strengths of the implants were determined. A significant increase in the central frequency was observed for the loose implants (mean pull‐out strength 21.1 ± 16.9 N), up to 6.4 kHz over 4 weeks. In comparison, the central frequency of the osseointegrated implants (105.2 ± 25.3 N) dropped to its initial value. The presented method shows potential for monitoring the osseointegration of different implant surfaces and could considerably reduce the number of animals needed for experiments. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:606–612, 2014. 相似文献
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43.
Albrecht Waschke Christin Hartmann Jan Walter Pedro Dünisch Falko Wahnschaff Rolf Kalff Christian Ewald 《Acta neurochirurgica》2014,156(2):235-244
Background
Different studies have shown that atrophy of paraspinal muscles arises after open dorsal lumbar fusion, and the reasons for this atrophy are still not yet fully clarified. This prospective study investigates the extent of atrophy of the lumbar paraspinal muscles after open lumbar interbody fusion, its possible causes, and their association with clinical outcome measures.Methods
Thirty consecutive patients were prospectively included (13 male, 17 female, median age 60.5 years, range 33–80 years). Mono or bisegmental, posterior lumbar interbody fusion and instrumentation was performed applying a conventional, open lumbar midline approach. Clinical outcome was assessed by the Short Form (36) Health Survey (SF-36) questionnaire and visual analogue scale. Needle electromyography of paraspinal muscles was performed preoperatively, at 6 and 12 months. Serum values of creatine kinase, lactate dehydrogenase and myoglobin were determined preoperatively, at day 2 after surgery and at discharge. Paraspinal muscle volume was determined by volumetric analysis of thin-slice computed tomography scans preoperatively and 1 year after surgery.Results
There was a significant increase of electromyographic denervation activity (p =0.024) and reduced recruitment of motor units (p?=?0.001) after 1 year. Laboratory studies showed a significant increase of CK (p?<?0.001) and myoglobin (p < 0.001) serum levels at day 2 after surgery. The paraspinal muscle volume decreased from 67.8 to 60.4 % (p < 0.001) after 1 year. Correlation analyses revealed a significant negative correlation between denervation and muscle volume (K = -0.219, p = 0.002). Paraspinal muscle volume is significantly correlated with physical outcome (K = 0.169, p = 0.020), mental outcome (K = 0.214, p = 0.003), and pain (K = 0.382, p < 0.001) after 1 year.Conclusions
Atrophy of paraspinal muscles after open, posterior lumbar interbody fusion seems to be associated with denervation, as well as direct muscle trauma during surgery. While muscle atrophy is also correlated with a worse clinical outcome, it seems to be a determining factor for successful lumbar spine surgery. 相似文献44.
Christian Ewald Pedro Duenisch Jan Walter Theresa Götz Otto W. Witte Rolf Kalff Albrecht Günther 《Neurocritical care》2014,20(1):91-97
Background
Autologous bone flap reinsertion follows as a second surgical intervention after decompressive craniectomy in patients with malignant middle cerebral artery (MCA) infarction. In addition to surgery-related short-term complications, aseptic resorption of the reimplanted bone flap is a possible long-term problem which has not yet been sufficiently elucidated in these patients.Methods
A total of 109 patients who had undergone decompressive hemicraniectomy for malignant MCA infarction in our institution between September 1994 and December 2011 were included in the study. Clinical and radiological findings were retrieved retrospectively. Aseptic bone necrosis was classified into two categories based on computer tomographic features.Results
A total of 76 patients received their own cryoconserved bone flap (mean age 54.34 ± 10.73 years; 49 males). The overall short-term complication rate was 9.2 %. Bone flap necrosis occurred in 26 patients (22.8 %) with 7 flaps showing signs of surgically relevant type II necrosis after a median time of 14 months (interquartile range [IQR] 4–22).Conclusions
There is a noticeable complication rate in patients undergoing bone flap reinsertion after hemicraniectomy due to malignant MCA infarction. Aseptic bone necrosis represents a significant complication during long-term follow-up. The pathophysiological mechanisms remain unclear and more efforts should be undertaken to understand and possibly prevent this complication in these patients. 相似文献45.
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47.
Ursula Friedrich Ole Mors Henrik Ewald 《American journal of medical genetics. Part A》1996,67(1):58-62
Systematic and detailed chromosome analysis, combined with a semistructured interview, was performed in 2 families with schizophrenia and in 2 families with manic depressive illness. Prometaphase technique did not reveal any subtle structural chromosome abnormalities. However, in standard techniques, gain and loss of sex chromosomes were observed. This occurred in patients at a younger age than in unaffected persons. This gives rise to the suspicion that sex chromosome aneuploidy may somehow be related to the development of psychosis. But since the data set is small, especially with respect to schizophrenia, further studies are needed to elucidate this observation. In one family, cosegregation of the disease locus with a marker on chromosome 21 was seen. Therefore, further research should determine if chromosome 21 contains a gene for manic depressive illness. © 1996 Wiley-Liss, Inc. 相似文献
48.
Matti O. Ruuskanen Pande P. Erawijantari Aki S. Havulinna Yang Liu Guillaume Mric Jaakko Tuomilehto Michael Inouye Pekka Jousilahti Veikko Salomaa Mohit Jain Rob Knight Leo Lahti Teemu J. Niiranen 《Diabetes care》2022,45(4):811
OBJECTIVETo examine the previously unknown long-term association between gut microbiome composition and incident type 2 diabetes in a representative population cohort.RESEARCH DESIGN AND METHODSWe collected fecal samples from 5,572 Finns (mean age 48.7 years; 54.1% women) in 2002 who were followed up for incident type 2 diabetes until 31 December 2017. The samples were sequenced using shotgun metagenomics. We examined associations between gut microbiome composition and incident diabetes using multivariable-adjusted Cox regression models. We first used the eastern Finland subpopulation to obtain initial findings and validated these in the western Finland subpopulation.RESULTSAltogether, 432 cases of incident diabetes occurred over the median follow-up of 15.8 years. We detected four species and two clusters consistently associated with incident diabetes in the validation models. These four species were Clostridium citroniae (hazard ratio [HR] 1.21; 95% CI 1.04–1.42), C. bolteae (HR 1.20; 95% CI 1.04–1.39), Tyzzerella nexilis (HR 1.17; 95% CI 1.01–1.36), and Ruminococcus gnavus (HR 1.17; 95% CI 1.01–1.36). The positively associated clusters, cluster 1 (HR 1.18; 95% CI 1.02–1.38) and cluster 5 (HR 1.18; 95% CI 1.02–1.36), mostly consisted of these same species.CONCLUSIONSWe observed robust species-level taxonomic features predictive of incident type 2 diabetes over long-term follow-up. These findings build on and extend previous mainly cross-sectional evidence and further support links between dietary habits, metabolic diseases, and type 2 diabetes that are modulated by the gut microbiome. The gut microbiome can potentially be used to improve disease prediction and uncover novel therapeutic targets for diabetes. 相似文献
49.
Dr. C. A. Ewald 《Virchows Archiv : an international journal of pathology》1879,75(3):409-419
Ohne ZusammenfassungNach einem in der Berliner medicin. Gesellschaft am 11. December 1878 gehaltenen Vortrag, mit Fortlassung der einleitenden und Schlussworte. 相似文献
50.