300 research outputs found
Bapineuzumab for mild to moderate Alzheimerâs disease in two global, randomized, phase 3 trials
Background Our objective was to evaluate the efficacy (clinical and biomarker)
and safety of intravenous bapineuzumab in patients with mild to moderate
Alzheimerâs disease (AD). Methods Two of four phase 3, multicenter,
randomized, double-blind, placebo-controlled, 18-month trials were conducted
globally: one in apolipoprotein E Δ4 carriers and another in noncarriers.
Patients received bapineuzumab 0.5 mg/kg (both trials) or 1.0 mg/kg
(noncarrier trial) or placebo every 13 weeks. Coprimary endpoints were change
from baseline to week 78 on the 11-item Alzheimerâs Disease Assessment
ScaleâCognitive subscale and the Disability Assessment for Dementia. Results A
total of 683 and 329 patients completed the current carrier and noncarrier
trials, respectively, which were terminated prematurely owing to lack of
efficacy in the two other phase 3 trials of bapineuzumab in AD. The current
trials showed no significant difference between bapineuzumab and placebo for
the coprimary endpoints and no effect of bapineuzumab on amyloid load or
cerebrospinal fluid phosphorylated tau. (Both measures were stable over time
in the placebo group.) Amyloid-related imaging abnormalities with edema or
effusion were confirmed as the most notable adverse event. Conclusions These
phase 3 global trials confirmed lack of efficacy of bapineuzumab at tested
doses on clinical endpoints in patients with mild to moderate AD. Some
differences in the biomarker results were seen compared with the other phase 3
bapineuzumab trials. No unexpected adverse events were observed. Trial
registration Noncarriers (3000) ClinicalTrials.gov identifier NCT00667810;
registered 24 Apr 2008. Carriers (3001) ClinicalTrials.gov identifier
NCT00676143; registered 2 May 2008
Multi-tier Loyalty Programs to Stimulate Customer Engagement
Customers differ in their purchase behavior, profitability, attitude toward the firm, and so on. These differences between customers have led to numerous firms introducing multi-tier loyalty programs. A multi-tier loyalty program explicitly distinguishes between customers by means of hierarchical tiers (e.g. Silver, Gold, Platinum) and assigns customers to different tiers based on their past purchase behavior. Next, customers in different tiers are provided varying levels of tangible rewards and intangible benefits, which are potentially powerful instruments to stimulate customer engagement. In this chapter, we focus on the design and effectiveness of such multi-tier loyalty programs. Building on loyalty program and customer prioritization research, we discuss whether, why, and how multi-tier loyalty programs are effective (or not) in influencing customer behavior, thereby enhancing customer engagement and financial performance
Clinical utility of tibial motor and sensory nerve conduction studies with motor recording from the flexor hallucis brevis: a methodological and reliability study
<p>Abstract</p> <p>Background</p> <p>Standard tibial motor nerve conduction measures are established with recording from the abductor hallucis. This technique is often technically challenging and clinicians have difficulty interpreting the information particularly in the short segment needed to assess focal tibial nerve entrapment at the medial ankle as occurs in posterior tarsal tunnel syndrome. The flexor hallucis brevis (FHB) has been described as an alternative site for recording tibial nerve function in those with posterior tarsal tunnel syndrome. Normative data has not been established for this technique. This pilot study describes the technique in detail. In addition we provide reference values for medial and lateral plantar orthodromic sensory measures and assessed intrarater reliability for all measures.</p> <p>Methods</p> <p>Eighty healthy female participants took part, and 39 returned for serial testing at 4 time points. Mean values ± SD were recorded for nerve conduction measures, and coefficient of variation as well as intraclass correlation coefficients (ICC) were calculated.</p> <p>Results</p> <p>Motor latency, amplitude and velocity values for the FHB were 4.1 ± 0.9 msec, 8.0 ± 3.0 mV and 45.6 ± 3.4 m/s, respectively. Sensory latencies, amplitudes, and velocities, respectively, were 2.8 ± 0.3 msec, 26.7 ± 10.1 ΌV, and 41.4 ± 3.5 m/s for the medial plantar nerve and 3.2 ± 0.5 msec, 13.3 ± 4.7 ΌV, and 44.3 ± 4.0 msec for the lateral plantar nerve. All values demonstrated significant ICC values (<it>P </it>†0.007).</p> <p>Conclusion</p> <p>Motor recording from the FHB provides technically clear waveforms that allow for an improved ability to assess tibial nerve function in the short segments used to assess tarsal tunnel syndrome. The reported means will begin to establish normal values for this technique.</p
Long-Lived Plasma Cells and Memory B Cells Produce Pathogenic Anti-GAD65 Autoantibodies in Stiff Person Syndrome
Stiff person syndrome (SPS) is a rare, neurological disorder characterized by sudden cramps and spasms. High titers of enzyme-inhibiting IgG autoantibodies against the 65 kD isoform of glutamic acid decarboxylase (GAD65) are a hallmark of SPS, implicating an autoimmune component in the pathology of the syndrome. Studying the B cell compartment and the anti-GAD65 B cell response in two monozygotic twins suffering from SPS, who were treated with the B cell-depleting monoclonal anti-CD20 antibody rituximab, we found that the humoral autoimmune response in SPS is composed of a rituximab-sensitive part that is rapidly cleared after treatment, and a rituximab-resistant component, which persists and acts as a reservoir for autoantibodies inhibiting GAD65 enzyme activity. Our data show that these potentially pathogenic anti-GAD65 autoantibodies are secreted by long-lived plasma cells, which may either be persistent or develop from rituximab-resistant memory B lymphocytes. Both subsets represent only a fraction of anti-GAD65 autoantibody secreting cells. Therefore, the identification and targeting of this compartment is a key factor for successful treatment planning of SPS and of similar autoimmune diseases
Seasonal temperatures in West Antarctica during the Holocene
The recovery of long-term climate proxy records with seasonal resolution is rare because of natural smoothing processes, discontinuities and limitations in measurement resolution. Yet insolation forcing, a primary driver of multimillennial-scale climate change, acts through seasonal variations with direct impacts on seasonal climate1. Whether the sensitivity of seasonal climate to insolation matches theoretical predictions has not been assessed over long timescales. Here, we analyse a continuous record of water-isotope ratios from the West Antarctic Ice Sheet Divide ice core to reveal summer and winter temperature changes through the last 11,000âyears. Summer temperatures in West Antarctica increased through the early-to-mid-Holocene, reached a peak 4,100âyears ago and then decreased to the present. Climate model simulations show that these variations primarily reflect changes in maximum summer insolation, confirming the general connection between seasonal insolation and warming and demonstrating the importance of insolation intensity rather than seasonally integrated insolation or season duration2,3. Winter temperatures varied less overall, consistent with predictions from insolation forcing, but also fluctuated in the early Holocene, probably owing to changes in meridional heat transport. The magnitudes of summer and winter temperature changes constrain the lowering of the West Antarctic Ice Sheet surface since the early Holocene to less than 162âm and probably less than 58âm, consistent with geological constraints elsewhere in West Antarctica4-7
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