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The photoinjector test facility at DESY, Zeuthen site (PITZ), was built to develop and optimize photoelectron sources for superconducting linacs for high-brilliance, short-wavelength free-electron laser (FEL) applications like the free-electron laser in Hamburg (FLASH) and the European x-ray free-electron laser (XFEL). In this paper, the detailed characterization of two laser-driven rf guns with different operating conditions is described. One experimental optimization of the beam parameters was performed at an accelerating gradient of about 43 MV/m at the photocathode and the other at about 60 MV/m. In both cases, electron beams with very high phase-space density have been demonstrated at a bunch charge of 1 nC and are compared with corresponding simulations. The rf gun optimized for the lower gradient has surpassed all the FLASH requirements on beam quality and rf parameters (gradient, rf pulse length, repetition rate) and serves as a spare gun for this facility. The rf gun studied with increased accelerating gradient at the cathode produced beams with even higher brightness, yielding the first demonstration of the beam quality required for driving the European XFEL: The geometric mean of the normalized projected rms emittance in the two transverse directions was measured to be 1.26±0.13 mm mrad for a 1-nC electron bunch. When a 10% charge cut is applied excluding electrons from those phase-space regions where the measured phase-space density is below a certain level and which are not expected to contribute to the lasing process, the normalized projected rms emittance is about 0.9 mm mrad.

Objective: This publication summarizes the clinical development of the compound SAR113945, an IκB kinase inhibitor injected intra-articularly in a slow-release formulation to treat patients with symptomatic osteoarthritis (OA) of the knee., Results: In vitro experiments demonstrated a specific inhibition of the IκB kinase complex. Profiling of SAR113945 on kinases, enzymes and ion channels supported the initiation of a clinical development. Cellular assay systems also revealed an inhibition in the synthesis of interleukin 1β, tumor necrosis factor α (TNFα) and the prostaglandin E2 (PGE 2 ). In vivo studies demonstrated positive effects of SAR113945 on thermal and mechanical hyperalgesia and even showed superiority in comparison with triamcinolone. Pharmacokinetic measurements showed a sustained release of dissolved SAR113945 locally supporting a comparably high exposure in the knee joint combined with a low systemic exposure. Three phase 1 studies with a dose-escalating design confirmed safety and tolerability of SAR113945. In those studies SAR113945 showed a positive trend on the WOMAC scores. The proof-of-concept or phase 2a study failed to show any effect in the overall group of recruited study participants for the primary endpoint, the WOMAC pain subscore at day 56, but showed a statistically significant difference in a subgroup of patients who had presented with effusion at baseline., Conclusion: Inhibiting the NFκB signaling pathway is an attractive method to treat patients with signs and symptoms of OA. The preclinical work and the results of the phase 1 studies appeared promising for a full clinical development, however, the proof-of-concept study failed to show efficacy in a larger patient sample size., (Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

To evaluate in an interventional trial on knee osteoarthritis (OA) the level and change of two serum biomarkers and their correlation with imaging parameters. The previously reported interventional OA study (ClinicalTrials.gov: NCT00536302) identified a positive effect of collagen hydrolysate (CH) on cartilage morphology in patients with knee OA using delayed gadolinium enhanced magnetic resonance imaging (dGEMRIC). It was the objective in this research project to evaluate in an interventional clinical trial on knee OA the level and change of two serum biomarkers and their correlation with imaging parameters. In blood samples of study participants, we determined the concentration of procollagen type II N-terminal propeptide (PIIANP) and aggrecan chondroitin sulfate 846 epitope (CS846) at baseline (BL) and at the follow-up (FU) visits at 24 and 48 weeks. We measured the level and change of biomarker concentrations in both study groups, and the correlation of those changes with changes in dGEMRIC. For the biomarker PIIANP, we observed a significantly greater increase in the CH group (29.9% vs. 1.2% at week 24, P= 0.001). For CS846, the mean concentration was lower among the CH treated participants at 24 weeks (78% vs. 96%, P= 0.045). Consistent correlations of changes in biomarkers PIIANP and CS846 with changes of the dGEMRIC score could not be observed. In this study, different changes per treatment group, CH and placebo were seen for dGEMRIC and PIIANP BL to 24 weeks FU, but only weak correlations between changes in dGEMRIC and biochemical markers.

Objective: To evaluate the extent to which the current designs of clinical trials in knee osteoarthritis (OA) permit detection of a therapeutic effect of disease-modifying OA drugs (DMOADs) on the incidence of knee replacement, and to provide estimates of the required sample sizes., Methods: We selected distinct subcohorts of the Osteoarthritis Initiative (OAI), based on available information on eligibility criteria for clinical knee OA trials (ClinicalTrials.gov) and additional subcohorts stratified for age, sex, and the severity of radiographic OA. The observed incidence of knee replacement in these OAI subcohorts was used to estimate the expected incidence of knee replacement in the control group of a clinical trial. Based on this estimate, the sample sizes required to detect hypothetical treatment effects on the incidence of knee replacement were calculated, assuming observation periods of 2, 5, or 7 years., Results: The cumulative knee replacement incidence rates in the OAI subcohorts ranged from 0.9% to 12.9%. The corresponding sample sizes required to detect 50% improvement by the DMOAD, with a power of 80% and 95% confidence, were 5,459 and 362, respectively. Including only women with advanced age and radiographic OA increased the incidence of knee replacement and decreased the required sample size., Conclusion: The sample sizes that are commonly used in clinical trials do not enable the effects of a DMOAD on incident knee replacement to be detected with sufficient power and confidence. The estimated incidence rates of knee replacement and the corresponding sample sizes are important for informing the design of trials for disease course-modifying effects as well as for socioeconomic evaluation of a DMOAD in terms of preventing knee replacement., (© 2015, American College of Rheumatology.)

Objective: To determine whether either of two magnetic resonance imaging approaches - delayed gadolinium enhanced magnetic resonance imaging of cartilage (dGEMRIC), or T2 mapping - can detect short-term changes in knee hyaline cartilage among individuals taking a formulation of collagen hydrolysate., Design: Single center, prospective, randomized, placebo-controlled, double-blind, pilot trial of collagen hydrolysate for mild knee osteoarthritis (OA). Participants were allowed to continue the prior analgesic use. The primary outcome was change in dGEMRIC T1 relaxation time in the cartilage regions of interest at the 24-week timepoint. Secondary endpoints included the change in dGEMRIC T1 relaxation time between baseline and 48 weeks, the change in T2 relaxation time at 0, 24 and 48 weeks, the symptom and functional measures obtained at each of the visits, and overall analgesic use., Results: Among a sample of 30 randomized subjects the dGEMRIC score increased in the medial and lateral tibial regions of interest (median increase of 29 and 41 ms respectively) in participants assigned to collagen hydrolysate but decreased (median decline 37 and 36 ms respectively) in the placebo arm with the changes between the two groups at 24 weeks reaching significance. No other significant changes between the two groups were seen in the other four regions, or in any of the T2 values or in the clinical outcomes., Conclusions: These preliminary results suggest that the dGEMRIC technique may be able to detect change in proteoglycan content in knee cartilage among individuals taking collagen hydrolysate after 24 weeks., (Copyright © 2011 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)