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71.

Objective

To study low blood hemoglobin concentrations as a predictor of radiographic damage progression in patients with rheumatoid arthritis (RA).

Methods

Post hoc analyses were performed in patients from the PREMIER trial with early RA undergoing 2 years of adalimumab (ADA), methotrexate (MTX), or ADA + MTX combination therapy. Low disease activity was defined as a score <3.2 on the 28‐joint Disease Activity Score using the C‐reactive protein level (DAS28‐CRP), and clinical response by the American College of Rheumatology criteria for 20% improvement at week 24. Baseline or mean hemoglobin concentrations over time, or anemia as defined using sex‐specific World Health Organization criteria, were analyzed in mixed‐effects models for longitudinal data in men and women as predictors of progressive joint damage, as measured by the modified total Sharp/van der Heijde score (ΔSHS). Data were adjusted for treatment and other patient characteristics, including the DAS28‐CRP.

Results

Baseline hemoglobin was inversely associated with ΔSHS in adjusted analyses (P < 0.05 for both sexes). Baseline anemia predicted greater ΔSHS in MTX‐treated patients over 104 weeks, and in ADA‐ and combination‐treated patients over 26 weeks. Lower hemoglobin concentrations over time, as well as time with anemia, were associated with greater damage progression (P < 0.001). The effect of low hemoglobin concentrations on joint damage progression remained significant, even in patients achieving low disease activity.

Conclusion

Low hemoglobin is a DAS28‐CRP‐independent predictor of radiographic joint damage progression in MTX‐treated patients with early RA. This effect decreases over time in ADA‐ and combination‐treated patients, and in clinical responders irrespective of treatment modality.
  相似文献   
72.
The mortality rate after acute myocardial infarction (AMI) has generally been modeled by a single exponential function. The present study was undertaken to determine, in 3 different populations, whether or not periods exist during the first year after AMI which have mortality distributions that differ from this pattern. The 3 patient populations included San Diego (346 patients, 71 deaths), Vancouver (704 patients, 146 deaths), and Copenhagen (1,140 patients, 262 deaths). Hospital admission was within 24 hours of the onset of symptoms, and patients dying within the first 24 hours after hospital admission or of noncardiac or unknown causes were not analyzed. The mortality between 2 and 21 days in the combined data base was 11.4% (range 10.9 to 11.7) and from 3 weeks to 1 year 10.5% (range 9.0 to 11.3). A high degree of similarity was noted among the shapes of the 3 survival curves. The hypothesis of an exponential mortality rate during the entire first year was rejected. Using a special statistic, changepoints at days 17,23, and 24 in the 3 populations (21 days for the combined data base) were identified and used thereafter to divide the year into 2 separate periods of mortality within which exponentiality for the mortality rate was not rejected. The point by which exactly 50% of deaths had occurred was day 19, with 75% of deaths occurring by day 100. These data further define the natural history after AMI and indicate optimal follow-up periods for short- and longer-term management strategies based on risk assessment or trials of risk reduction after AMI.  相似文献   
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The use of immunoglobulin (Ig) preparations (intravenous, IVIg, subcutaneous, SCIg) for replacement and immunomodulation therapy worldwide has tripled in the past 20 years and represents an ever‐increasing cost factor for healthcare organizations. The limited access to the starting material of this essential medicinal product is currently the driving force for human plasma collection. Increasing awareness and improved diagnosis of human primary immunodeficiencies and a broadening of immunomodulatory indications are responsible for this development, and on a longer run might lead to plasma supply shortages. Consensus recommendations for the optimal use of Ig in clinical practice, including priority rankings for the most urgent indications, are therefore urgently needed. During a recent meeting in Kreuth, Germany, expert nominees from 36 Council of Europe states, together with colleagues from observer countries and regulatory agencies came up with this consensus statement.

  相似文献   

75.
All-solid microstructured optical fibers (MOF) allow the realization of very flexible optical waveguide designs. They are prepared by stacking of doped silica rods or canes in complex arrangements. Typical dopants in silica matrices are germanium and phosphorus to increase the refractive index (RI), or boron and fluorine to decrease the RI. However, the direct interface contact of stacking elements often causes interrelated chemical reactions or evaporation during thermal processing. The obtained fiber structures after the final drawing step thus tend to deviate from the targeted structure risking degrading their favored optical functionality. Dopant profiles and design parameters (e.g., the RI homogeneity of the cladding) are controlled by the combination of diffusion and equilibrium conditions of evaporation reactions. We show simulation results of diffusion and thermal dissociation in germanium and fluorine doped silica rod arrangements according to the monitored geometrical disturbances in stretched canes or drawn fibers. The paper indicates geometrical limits of dopant structures in sub-µm-level depending on the dopant concentration and the thermal conditions during the drawing process. The presented results thus enable an optimized planning of the preform parameters avoiding unwanted alterations in dopant concentration profiles or in design parameters encountered during the drawing process.  相似文献   
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78.
To identify cooperating lesions in core-binding factor acute myeloid leukemia, we performed single-nucleotide polymorphism-array analysis on 300 diagnostic and 41 relapse adult and pediatric leukemia samples. We identified a mean of 1.28 copy number alterations per case at diagnosis in both patient populations. Recurrent minimally deleted regions (MDRs) were identified at 7q36.1 (7.7%), 9q21.32 (5%), 11p13 (2.3%), and 17q11.2 (2%). Approximately one-half of the 7q deletions were detectable only by single-nucleotide polymorphism-array analysis because of their limited size. Sequence analysis of MLL3, contained within the 7q36.1 MDR, in 46 diagnostic samples revealed one truncating mutation in a leukemia lacking a 7q deletion. Recurrent focal gains were identified at 8q24.21 (4.7%) and 11q25 (1.7%), both containing a single noncoding RNA. Recurrent regions of copy-neutral loss-of-heterozygosity were identified at 1p (1%), 4q (0.7%), and 19p (0.7%), with known mutated cancer genes present in the minimally altered region of 1p (NRAS) and 4q (TET2). Analysis of relapse samples identified recurrent MDRs at 3q13.31 (12.2%), 5q (4.9%), and 17p (4.9%), with the 3q13.31 region containing only LSAMP, a putative tumor suppressor. Determining the role of these lesions in leukemogenesis and drug resistance should provide important insights into core-binding factor acute myeloid leukemia.  相似文献   
79.
Standardized criteria for diagnosis and response evaluation in chronic lymphocytic leukemia (CLL) are essential to achieve comparability of results and improvement of clinical care. With the increasing range of therapeutic options, the treatment context is important when defining refractory CLL. Refractory CLL has been defined as no response or response lasting ≤ 6 months from last therapy. This subgroup has a very poor outcome, and many trials use this group as an entry point for early drug development. With the intensification of first-line regimens, the proportion of patients with refractory CLL using these criteria decreases. This has immediate consequences for recruitment of patients into trials as well as salvage strategies. Conversely, patients who are not refractory according to the traditional definition but who have suboptimal or short response to intense therapy also have a very poor outcome. In this Perspective, we discuss recent results that may lead to a reassessment of risk categories in CLL focusing on fit patients who are eligible for all treatment options. We cover aspects of the history and biologic basis for refractory CLL and will focus on how emerging data on treatment failure from large trials using chemoimmunotherapy may help to define risk groups in CLL.  相似文献   
80.
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