586 research outputs found

    Asset Allocation for Retirement: Simple Heuristics and Target-Date Funds

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    We examine common asset allocation strategies for retirement investing, considering both static and dynamic approaches, as well as those allocation policies used by leading target-date fund providers. We studied the average performance of each strategy over historical rolling periods (that is, bootstrapping), using actual annual returns starting in 1926. Then we applied the simulation method to review potential future results, as well as to provide additional insight into the structure and characteristics of each approach. We find that, over time, certain static approaches are essentially equivalent to dynamic strategies that reduce equity exposure through time. Further, we find that most target-date fund providers appear to target a dynamic 120 - age equity allocation. We suggest that financial planners consider a 100 percent equity allocation for their clients until approximately 10 years prior to a client\u27s retirement, at which point a more conservative allocation should be employed. Although the average outcome for this approach is technically better there is still significant risk associated with this strategy. Consider the outcome should the year prior to reallocation be like 2008, or the inherent difficulties of a large shift from 100 percent equity to 45 percent equity because of tax or other issues. A more moderate reallocation over a few years may be reasonable. This flexibility suggests that financial planners can play a valuable role by helping investors determine the optimal reallocation time and process, in addition to encouraging a larger equity exposure early on to capture the benefits thereof

    PowerPoint Games in a Secondary Laptop Environment

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    There is no denying the success and popularity of WebQuests among teachers. For those interested in technology integration, this is a significant step in the right direction. Yet, WebQuests are instructivist examples of technology integration – they are web-enhanced forms of direct instruction. We consider constructing homemade PowerPoint games as a constructionist alternative to WebQuests. PowerPoint is nearly ubiquitous software and teachers already use existing games in their classrooms. The authors contend that a better use of class time for learning is to turn over the act of game design to the children themselves. In this project, students in social studies course delivered by a mid-western high school designed PowerPoint Games as a means to review for portions of two examinations

    A new approach for improving coronary plaque component analysis based on intravascular ultrasound images

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    Virtual histology intravascular ultrasound (VH-IVUS) is a clinically available technique for atherosclerosis plaque characterization. It, however, suffers from a poor longitudinal resolution due to electrocardiogram (ECG)-gated acquisition. This article presents an effective algorithm for IVUS image-based histology to overcome this limitation. After plaque area extraction within an input IVUS image, a textural analysis procedure consisting of feature extraction and classification steps is proposed. The pixels of the extracted plaque area excluding the shadow region were classified into one of the three plaque components of fibro-fatty (FF), calcification (CA) or necrotic core (NC) tissues. The average classification accuracy for pixel and region based validations is 75% and 87% respectively. Sensitivities (specificities) were 79% (85%) for CA, 81% (90%) for FF and 52% (82%) for NC. The kappa (kappa) = 0.61 and p value = 0.02 indicate good agreement of the proposed method with VH images. Finally, the enhancement in the longitudinal resolution was evaluated by reconstructing the IVUS images between the two sequential IVUS-VH images

    Do Acute Coronary Events Affect Lipid Management and Cholesterol Goal Attainment in Germany?

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    Objective To document utilization of lipid-lowering therapy, attainment of low-density lipoprotein cholesterol target values, and cardiovascular outcomes in patients hospitalized for acute coronary syndrome in Germany. Methods The Dyslipidemia International Study II was a multicenter, observational study of the prevalence of dyslipidemia and lipid target value attainment in patients surviving any acute coronary syndrome event. Among patients on lipid-lowering therapy for ≥3 months, use of lipid-lowering therapy and lipid profiles were assessed at admission and again at 120 ± 15 days after admission (the follow-up time point). Multivariate logistic regression was used to identify variables predictive of low-density lipoprotein cholesterol target value attainment in patients using lipid-lowering therapy. Results A total of 461 patients hospitalized for acute coronary syndrome were identified, 270 (58.6%) of whom were on lipid-lowering therapy at admission. Among patients on lipid-lowering therapy, 90.7% and 85.9% were receiving statin monotherapy at admission and follow-up, respectively. Mean (SD) lowdensity lipoprotein cholesterol levels in patients on lipid-lowering therapy were 101 (40) mg/dl and 95 (30) mg/dl at admission and follow-up, respectively. In patients with data at both admission and followup (n= 61), low-density lipoprotein cholesterol target value attainment rates were the same (19.7%) at both time points. Smoking was associated with a 77% lower likelihood of attaining the low-density lipoprotein cholesterol target value. Conclusion Hospitalization for an acute event does not greatly alter lipid management in acute coronary syndrome patients in Germany. Both lipid-lowering therapy doses and rates of low-density lipoprotein cholesterol target value attainment remained essentially the same several months after the event

    T helper cell subsets specific for pseudomonas aeruginosa in healthy individuals and patients with cystic fibrosis

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    Background: We set out to determine the magnitude of antigen-specific memory T helper cell responses to Pseudomonas aeruginosa in healthy humans and patients with cystic fibrosis. Methods: Peripheral blood human memory CD4+ T cells were co-cultured with dendritic cells that had been infected with different strains of Pseudomonas aeruginosa. The T helper response was determined by measuring proliferation, immunoassay of cytokine output, and immunostaining of intracellular cytokines. Results: Healthy individuals and patients with cystic fibrosis had robust antigen-specific memory CD4+ T cell responses to Pseudomonas aeruginosa that not only contained a Th1 and Th17 component but also Th22 cells. In contrast to previous descriptions of human Th22 cells, these Pseudomonal-specific Th22 cells lacked the skin homing markers CCR4 or CCR10, although were CCR6+. Healthy individuals and patients with cystic fibrosis had similar levels of Th22 cells, but the patient group had significantly fewer Th17 cells in peripheral blood. Conclusions: Th22 cells specific to Pseudomonas aeruginosa are induced in both healthy individuals and patients with cystic fibrosis. Along with Th17 cells, they may play an important role in the pulmonary response to this microbe in patients with cystic fibrosis and other conditions

    Identification of SOX2 as a novel glioma-associated antigen and potential target for T cell-based immunotherapy

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    Prognosis for patients suffering from malignant glioma has not substantially improved. Specific immunotherapy as a novel treatment concept critically depends on target antigens, which are highly overexpressed in the majority of gliomas, but the number of such antigens is still very limited. SOX2 was identified by screening an expression database for transcripts that are overexpressed in malignant glioma, but display minimal expression in normal tissues. Expression of SOX2 mRNA was further investigated in tumour and normal tissues by real-time PCR. Compared to cDNA from pooled normal brain, SOX2 was overexpressed in almost all (9 out of 10) malignant glioma samples, whereas expression in other, non-malignant tissues was almost negligible. SOX2 protein expression in glioma cell lines and tumour tissues was verified by Western blot and immunofluorescence. Immunohistochemistry demonstrated SOX2 protein expression in all malignant glioma tissues investigated ranging from 6 to 66% stained tumour cells. Human leucocyte antigen-A*0201-restricted SOX2-derived peptides were tested for the activation of glioma-reactive CD8+ cytotoxic T lymphocytes (CTLs). Specific CTLs were raised against the peptide TLMKKDKYTL and were capable of lysing glioma cells. The abundant and glioma-restricted overexpression of SOX2 and the generation of SOX2-specific and tumour-reactive CTLs may recommend this antigen as target for T-cell-based immunotherapy of glioma

    Acellular Pertussis Booster in Adolescents Induces Th1 and Memory CD8+ T Cell Immune Response

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    In a number of countries, whole cell pertussis vaccines (wcP) were replaced by acellular vaccines (aP) due to an improved reactogenicity profile. Pertussis immunization leads to specific antibody production with the help of CD4+ T cells. In earlier studies in infants and young children, wcP vaccines selectively induced a Th1 dominated immune response, whereas aP vaccines led to a Th2 biased response. To obtain data on Th1 or Th2 dominance of the immune response in adolescents receiving an aP booster immunization after a wcP or aP primary immunization, we analyzed the concentration of Th1 (IL-2, TNF-α, INF-γ) and Th2 (IL-4, IL-5, IL-10) cytokines in supernatants of lymphocyte cultures specifically stimulated with pertussis antigens. We also investigated the presence of cytotoxic T cell responses against the facultative intracellular bacterium Bordetella pertussis by quantifying pertussis-specific CD8+ T cell activation following the aP booster immunization. Here we show that the adolescent aP booster vaccination predominantly leads to a Th1 immune response based on IFNgamma secretion upon stimulation with pertussis antigen, irrespective of a prior whole cell or acellular primary vaccination. The vaccination also induces an increase in peripheral CD8+CD69+ activated pertussis-specific memory T cells four weeks after vaccination. The Th1 bias of this immune response could play a role for the decreased local reactogenicity of this adolescent aP booster immunization when compared to the preceding childhood acellular pertussis booster. Pertussis-specific CD8+ memory T cells may contribute to protection against clinical pertussis

    Symptoms, disease severity and treatment of adults with a new diagnosis of severe aortic stenosis

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    Objective Contemporary data on patients with previously undiagnosed severe aortic stenosis (AS) are scarce. We aimed to address this gap by gathering data from consecutive patients diagnosed with severe AS on echocardiography. Methods This was a prospective, multicentre, multinational, registry in 23 tertiary care hospitals across 9 European countries. Patients with a diagnosis of severe AS were included using echocardiography (aortic valve area (AVA) <1 cm 2, indexed AVA <0.6 cm 2 /m 2, maximum jet-velocity (V max) >4 m/s and/or mean transvalvular gradient >40 mm Hg). Results The 2171 participants had a mean age of 77.9 years and 48.0% were female. The mean AVA was 0.73 cm 2, V max 4.3 m/s and mean gradient 47.1 mm Hg; 62.1% had left ventricular hypertrophy and 27.3% an ejection fraction (EF) <50%. 1743 patients (80.3%) were symptomatic (shortness-of-breath 91.0%; dizziness 30.2%, chest pain 28.9%). Patients had a EuroSCORE II of 4.0; 25.3% had a creatinine clearance <50 mL/min, and 3.2% had an EF <30%. Symptomatic patients were older and had more comorbidities than asymptomatic patients. Despite European Society of Cardiology 2017 valvular heart disease guideline class I recommendation, in only 76.2% a decision was made for an intervention (transcatheter 50.4%, surgical aortic valve replacement 25.8%). In asymptomatic patients, 57.7% with a class I/IIa indication were scheduled for a procedure, while 36.3% patients without an indication had their valve replaced. Conclusions The majority of patients with severe AS presented at an advanced disease stage. Management of severe AS remained suboptimal in a significant proportion of contemporary patients with severe AS. Trial registration number NCT02241447;Results

    Facilitated Data Relay and Effects on Treatment of Severe Aortic Stenosis in Europe

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    Background: Many patients with severe aortic stenosis are referred late with advanced symptoms or inappropriately denied intervention. The objective was to investigate whether a structured communication to referring physicians (facilitated data relay) might improve the rate and timeliness of intervention. Methods and Results: A prospective registry of consecutive patients with severe aortic stenosis at 23 centers in 9 European countries with transcatheter as well as surgical aortic valve replacement being available was performed. The study included a 3-month documentation of the status quo (phase A), a 6-month intervention phase (implementing facilitated data relay), and a 3-month documentation of a legacy effect (phase-B). Two thousand one hundred seventy-one patients with severe aortic stenoses were enrolled (phase A: 759; intervention: 905; phase-B: 507). Mean age was 77.9±10.0 years, and 80% were symptomatic, including 52% with severe symptoms. During phase A, intervention was planned in 464/696 (67%), 138 (20%) were assigned to watchful waiting, 8 (1%) to balloon aortic valvuloplasty, 60 (9%) were listed as not for active treatment, and in 26 (4%), no decision was made. Three hundred sixty-three of 464 (78%) patients received the planned intervention within 3 months. Timeliness of the intervention improved as shown by the higher number of aortic valve replacements performed within 3 months (59% versus 51%, P=0.002) and a significant decrease in the time to intervention (36±38 versus 30±33 days, P=0.002). Conclusions: A simple, low-cost, facilitated data relay improves timeliness of treatment for patients diagnosed with severe aortic stenosis, resulting in a shorter time to transcatheter aortic valve replacement. This effect was mainly driven by a significant improvement in timeliness of intervention in transcatheter aortic valve replacement but not surgical aortic valve replacement. Clinical Trial Registration: URL: https://www.clinicaltrials.gov/. Unique identifier: NCT02241447

    A Novel Modular Antigen Delivery System for Immuno Targeting of Human 6-sulfo LacNAc-Positive Blood Dendritic Cells (SlanDCs)

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    Previously, we identified a major myeloid-derived proinflammatory subpopulation of human blood dendritic cells which we termed slanDCs (e.g. Schäkel et al. (2006) Immunity 24, 767-777). The slan epitope is an O-linked sugar modification (6-sulfo LacNAc, slan) of P-selectin glycoprotein ligand-1 (PSGL-1). As slanDCs can induce neoantigen-specific CD4+ T cells and tumor-reactive CD8+ cytotoxic T cells, they appear as promising targets for an in vivo delivery of antigens for vaccination. However, tools for delivery of antigens to slanDCs were not available until now. Moreover, it is unknown whether or not antigens delivered via the slan epitope can be taken up, properly processed and presented by slanDCs to T cells.Single chain fragment variables were prepared from presently available decavalent monoclonal anti-slan IgM antibodies but failed to bind to slanDCs. Therefore, a novel multivalent anti-slanDC scaffold was developed which consists of two components: (i) a single chain bispecific recombinant diabody (scBsDb) that is directed on the one hand to the slan epitope and on the other hand to a novel peptide epitope tag, and (ii) modular (antigen-containing) linker peptides that are flanked at both their termini with at least one peptide epitope tag. Delivery of a Tetanus Toxin-derived antigen to slanDCs via such a scBsDb/antigen scaffold allowed us to recall autologous Tetanus-specific memory T cells.In summary our data show that (i) the slan epitope can be used for delivery of antigens to this class of human-specific DCs, and (ii) antigens bound to the slan epitope can be taken up by slanDCs, processed and presented to T cells. Consequently, our novel modular scaffold system may be useful for the development of human vaccines
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