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991.
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Emilie Le Rhun Patrick Devos Johannes Weller Katharina Seystahl Francesca Mo Annette Compter Anna S Berghoff Joost L M Jongen Fabian Wolpert Roberta Rud Dieta Brandsma Martin van den Bent Matthias Preusser Ulrich Herrlinger Michael Weller 《Neuro-oncology》2021,23(7):1100
Background The EANO ESMO guidelines have proposed a classification of leptomeningeal metastases (LM) from solid cancers based on clinical, magnetic resonance imaging (MRI), and cerebrospinal fluid (CSF) cytology presentation. MRI patterns are classified as linear, nodular, both, or neither. Type I LM is defined by positive CSF cytology (confirmed LM) whereas type II LM is defined by typical clinical and MRI signs (probable or possible LM). Here we explored the clinical utility of these LM subtypes.Patients and methodsWe retrospectively assembled data from 254 patients with newly diagnosed LM from solid tumors. Survival curves were derived using the Kaplan–Meier method and compared by Log-rank test.ResultsMedian age at LM diagnosis was 56 years. Typical clinical LM features were noted in 225 patients (89%); 13 patients (5%) were clinically asymptomatic. Tumor cells in the CSF were observed in 186 patients (73%) whereas the CSF was equivocal in 24 patients (9.5%) and negative in 44 patients (17.5%). Patients with confirmed LM had inferior outcome compared with patients with probable or possible LM (P = 0.006). Type I patients had inferior outcome than type II patients (P = 0.002). Nodular disease on MRI was a negative prognostic factor in type II LM (P = 0.014), but not in type I LM. On multivariate analysis, administration of either intrathecal pharmacotherapy (P = 0.012) or systemic pharmacotherapy (P = 0.0003) was associated with improved outcome in type I LM, but not in type II LM.ConclusionThe EANO ESMO LM subtypes are highly prognostic and should be considered for stratification and overall design of clinical trials. 相似文献
994.
Andreas Modler Heinz Fabian Fabian Sokolowski Gudrun Lutsch Klaus Gast Gregor Damaschun 《Amyloid》2013,20(4):215-231
Amyloid protofibril formation of phosphoglycerate kinase (PGK) and Syrian hamster prion protein (SHaPrP(90-232)) were investigated by static and dynamic light scattering, size exclusion chromatography and electron microscopy. Changes in secondary structure were monitored by Fourier transform infrared spectroscopy and by circular dichroism. Protofibril formation of the two proteins is found to be a two-stage process. At the beginning, an ensemble of critical oligomers is built up. These critical oligomeric states possess a predominant β-sheet structure and do not interact considerably with monomers. Initial oligomerization and transition to β-sheet structure are coupled events differing in their details for both proteins. Intermediate oligomeric states (dimers, trimers, etc.) are populated in case of PGK, whereas SHaPrP(90-232) behaves according to an apparent two-state reaction between monomers and octamers rich in β-structure with a reaction order varying between 2 and 4. All oligomers coalesce to PGK protofibrils in the second stage, while SHaPrP(90-232) protofibrils are only formed by a subpopulation. The rates of both growth stages can be tuned in case of PGK by different salts preserving the underlying generalized diffusion-collision mechanism. The different kinetics of the early misfolding and oligomerization events of the two proteins argue against a common mechanism of protofibril formation. A classification scheme for misassembly mechanisms of proteins based on energy landscapes is presented. It includes scenarios of downhill polymerization to which protofibril formation of PGK and SHaPrP(90-232) belong. 相似文献
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Characterization of non-calcified coronary atherosclerotic plaque by multi-detector row CT: comparison to IVUS 总被引:6,自引:0,他引:6
Pohle K Achenbach S Macneill B Ropers D Ferencik M Moselewski F Hoffmann U Brady TJ Jang IK Daniel WG 《Atherosclerosis》2007,190(1):174-180
Multi-detector row Computed Tomography (MDCT) permits non-invasive visualization of the coronary arteries. The ability to visualize and, with limitations, to characterize non-calcified coronary atherosclerotic plaque has been described. We investigated the CT attenuation of non-calcified plaques as determined by 16-slice MDCT in comparison to intravascular ultrasound (IVUS). METHODS AND RESULTS: Thirty-two patients were investigated by contrast-enhanced 16-slice CT. In addition, IVUS of one coronary artery (motorized pullback) was performed (LM+LAD: 22, LM+LCX: 4, RCA: 6). At 252 sites within the coronary system, in which non-calcified atherosclerotic plaque could be identified both in MDCT and IVUS, the CT attenuation within the plaque was measured using a centrally placed region of interest and correlated to the appearance of the plaque in IVUS at the corresponding location. The mean CT attenuation within plaque that corresponded to hyper-echogenic appearance in IVUS was 121+/-34HU (n=76). The mean CT attenuation within plaque that corresponded to hypo-echogenic appearance was 58+/-43HU (n=176, p<0.001). However, there was substantial overlap of the density values measured by MDCT in the two groups. CONCLUSIONS: A significant difference of the mean CT attenuation within atherosclerotic lesions of hypo-echogenic and hyper-echogenic appearance in IVUS could be observed. However, we observed substantial overlap of attenuation values between plaque types so that the differentiation of "vulnerable" and "stable" plaques based on their CT attenuation is doubtful. 相似文献
998.
Brodsky JW Baum BS Pollo FE Mehta H 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2007,28(2):162-165
BACKGROUND: Arthrodesis of the first metatarsophalangeal (MTP) joint is a common procedure with a proven long-term success rate. However, there is limited scientific information on its functional results. There is little data in the literature about changes in gait parameters after first MTP joint arthrodesis. The purpose of this study was to objectively evaluate the effects of first MTP joint arthrodesis on gait. METHODS: Twenty-three patients with symptomatic hallux rigidus refractory to nonoperative treatment were treated with first MTP joint arthrodesis. A prospective gait analysis study was performed on all patients at an average of 8.6 days before surgery and then again at least 1 year postoperatively. Preoperative and postoperative data from the patients were compared to determine differences in clinically relevant temporal-spatial, kinematic, and kinetic parameters of gait. RESULTS: There were three statistically significant changes in gait: increases in maximal ankle push-off power and single-limb support time on the involved extremity, and a decrease in step width. CONCLUSIONS: First MTP joint arthrodesis produces objective improvement in propulsive power, weightbearing function of the foot, and stability during gait. 相似文献
999.
Brodsky JW Pollo FE Cheleuitte D Baum BS 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2007,28(8):880-889
BACKGROUND: Patients with neuropathic conditions may develop plantar bony deformities through neuropathic collapse, frequently placing the skin and soft tissues at risk. Orthoses have been used to accommodate and distribute plantar pressures over a large surface area, thereby minimizing peak loading pressures in small regions and reducing the risk of ulceration. METHODS: A previously described bony prominence model (Brodsky et al.) was used to test the pressure-absorbing and force-transmission properties of various orthotic material combinations used in our outpatient clinic. Six materials were tested in five combinations of materials for their compressive properties: [MS]: medium plastazote (M) + soft plastazote (S); [MN]: medium plastazote (M) + nickelplast (N); [NP] nickelplast (N) + Poron (P); [MO] medium plastazote (M) + Spenco (O); and [MC] medium plastazote (M) + P-cell (C). Materials were tested for 100,000 cycles using a materials-testing system (MTS) apparatus (MTS Systems Corporation, Cary, NC) and software. Stress-strain curves comparing the measured peak pressure to the elastic deformation, or the percentage of compression a material experiences with respect to its original thickness, were plotted for each orthotic combination. RESULTS: For MS, MN, MO, and to a lesser extent, MC, a trend was noted for decreased elastic deformation with increased testing. Additionally, the peak pressures before and after testing for each 10,000 testing cycle for each of the orthotic combinations were plotted. For both MN and NP, no demonstrable difference was noted in the peak pressures in the pretesting and post-testing for the 100,000 cycles. The MO showed a trend for increased peak pressures after each testing cycle. Both the MC and MS peak pressures markedly increased with respect to pretesting value. Also, the MN, MO, and MS all showed an overall trend for increased load cell values with increasing cycles at fast loading. CONCLUSIONS: These data showed that some orthotic combinations are more effective than others at reducing peak pressures during compression testing using our bony prominence model. Further studies are needed to test the orthotic combinations for shear and combined shear and compression modes. 相似文献
1000.
Croce MA Magnotti LJ Savage SA Wood GW Fabian TC 《Journal of the American College of Surgeons》2007,204(5):935-9; discussion 940-2
BACKGROUND: An alternative to embolization or external pelvic fixation (EPF) in patients with multiple pelvic fractures and hemorrhage is a pelvic orthotic device (POD), which may easily be placed in the resuscitation area. Little published information is available about its effectiveness. This study evaluated the efficacy of the POD compared with EPF in patients with life-threatening pelvic fractures. STUDY DESIGN: We evaluated patients with blunt pelvic fractures over a 10-year period. Inclusion required multiple pelvic fractures with vascular disruption and severe retroperitoneal hematoma, open book fracture with symphysis diastasis, or sacroiliac disruption with vertical shear. Patients with EPF were compared with those in whom a POD was used. Outcomes included transfusions, hospital stay, and mortality. RESULTS: There were 3,359 patients with pelvic fractures who were admitted: 186 (6%) met entry criteria; 93 had EPF and 93 had POD. There were no differences in age or shock severity. Both 24-hour (4.9 versus 17.1 U, p < 0.0001) and 48-hour transfusions (6.0 versus 18.6 U, p < 0.0001) were reduced with POD. Twenty-three percent of each group underwent pelvic angiography, and 24-hour transfusion amounts for those patients were also reduced with POD (9.9 versus 21.5 U, p < 0.007). Hospital length of stay (16.5 versus 24.4 days, p < 0.03) was less with POD. Although there was decreased mortality with POD (26%) versus EPF (37%), it was not statistically significant (p=0.11). CONCLUSIONS: The therapeutic shift to POD has substantially reduced transfusion requirements and length of hospital stay, and has reduced mortality in patients with unstable pelvic fractures. POD has made a major contribution to the care of critically injured patients with the most severe pelvic fractures. 相似文献