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71.
Sage Hahn Scott Mackey Janna Cousijn John J. Foxe Andreas Heinz Robert Hester Kent Hutchinson Falk Kiefer Ozlem Korucuoglu Tristram Lett Chiang-Shan R. Li Edythe London Valentina Lorenzetti Luijten Maartje Reza Momenan Catherine Orr Martin Paulus Lianne Schmaal Rajita Sinha Zsuzsika Sjoerds Dan J. Stein Elliot Stein Ruth J. van Holst Dick Veltman Henrik Walter Reinout W. Wiers Murat Yucel Paul M. Thompson Patricia Conrod Nicholas Allgaier Hugh Garavan 《Human brain mapping》2022,43(1):555-565
To identify neuroimaging biomarkers of alcohol dependence (AD) from structural magnetic resonance imaging, it may be useful to develop classification models that are explicitly generalizable to unseen sites and populations. This problem was explored in a mega-analysis of previously published datasets from 2,034 AD and comparison participants spanning 27 sites curated by the ENIGMA Addiction Working Group. Data were grouped into a training set used for internal validation including 1,652 participants (692 AD, 24 sites), and a test set used for external validation with 382 participants (146 AD, 3 sites). An exploratory data analysis was first conducted, followed by an evolutionary search based feature selection to site generalizable and high performing subsets of brain measurements. Exploratory data analysis revealed that inclusion of case- and control-only sites led to the inadvertent learning of site-effects. Cross validation methods that do not properly account for site can drastically overestimate results. Evolutionary-based feature selection leveraging leave-one-site-out cross-validation, to combat unintentional learning, identified cortical thickness in the left superior frontal gyrus and right lateral orbitofrontal cortex, cortical surface area in the right transverse temporal gyrus, and left putamen volume as final features. Ridge regression restricted to these features yielded a test-set area under the receiver operating characteristic curve of 0.768. These findings evaluate strategies for handling multi-site data with varied underlying class distributions and identify potential biomarkers for individuals with current AD. 相似文献
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Kahn KL MacLean CH Liu H Rubenstein LZ Wong AL Harker JO Chen WP Fitzpatrick DM Bulpitt KJ Traina SB Mittman BS Hahn BH Paulus HE 《Medical care》2007,45(1):55-65
BACKGROUND: Patients with rheumatoid arthritis (RA) provide an important opportunity for understanding care of patients with a serious chronic condition. OBJECTIVES: We sought to characterize the complexity of care for patients with RA, including metrics describing the patient, the disease, and use of the health care system across time and place. METHODS: We undertook a prospective cohort study of 568 community-dwelling patients with RA by using observational data from clinically detailed telephone interviews at baseline and 2 years later in addition to medical record abstraction. Health status, comorbidity, use of disease-modifying antirheumatic drugs, visits, providers, provider types, encounter settings, and the discontinuity between patients and providers were studied. RESULTS: Within a 12-month window, 568 patients had 8686 outpatient encounters with the health care system with a mean of 3.41 unique providers per patient associated with a mean of 5 primary care and 6 rheumatologist visits. Half did not see a primary care physician, and 20% did not see a rheumatologist during 6-month periods despite their use of potentially toxic drugs, a mean of 4 comorbidities and progressive RA. Over the course of 24 months, 29% of patients changed their primary care provider, and 15% changed their rheumatologist. Patients were moderately impaired with mean SF-12 physical component score 37 (SD, 9). CONCLUSION: Patients with RA have frequent encounters with multiple providers and also frequent discontinuity of care. Recognizing the complexity of the care of patients with a chronic disease across multiple dimensions provides an opportunity to better understand challenges and opportunities in delivering high quality care. 相似文献
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Canisius Julian Wagner Andrea Bunk Eva Christina Spille Dorothee Cäcilia Stögbauer Louise Grauer Oliver Hess Katharina Thomas Christian Paulus Werner Stummer Walter Senner Volker Brokinkel Benjamin 《Neurosurgical review》2022,45(4):2767-2775
Neurosurgical Review - Treatment of meningiomas refractory to surgery and irradiation is challenging and effective chemotherapies are still lacking. Recently, in vitro analyses revealed decitabine... 相似文献
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Mark W. Zawadsky Megan C. Paulus Patrick J. Murray Matthew A. Johansen 《The Journal of arthroplasty》2014
This study evaluated early postoperative results of 150 consecutive primary total hip arthroplasties performed by a single surgeon; 50 from mini-incision posterior approach, 50 during the learning curve for the direct anterior approach, and 50 subsequent cases when the approach was routine. The anterior approach groups had significantly reduced hospital length of stays (2.9 and 2.7 days versus 3.9 days for the posterior group; P < 0.0001) and discharge to home versus rehab was more likely (80% and 84% in anterior groups, 56% in posterior group; P = 0.0028). In the anterior groups, there was significantly less use of assistive devices and narcotics at 6 weeks, and pain was significantly lower. Primary total hip arthroplasty using the anterior approach allows for superior recovery in a matched cohort of patients. 相似文献
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Regulation of interleukin-12 expression in human monocytes: selective priming by interferon-gamma of lipopolysaccharide-inducible p35 and p40 genes 总被引:24,自引:4,他引:24
Interleukin-12 (IL-12) is a monocyte/macrophage-derived cytokine that is critical for T lymphocyte and natural killer cell activities and functions. In this study, we examined the regulation of IL-12 expression by human monocytes in response to bacterial lipopolysaccharide (LPS). Several novel aspects of IL-12 induction from monocytes were shown. Optimal expression of IL-12 mRNA and bioactivity required specific priming of monocytes by interferon-gamma (IFN-gamma) before LPS stimulation. Granulocyte-macrophage colony-stimulating factor (GM-CSF) provided an equivalent priming stimulus for LPS-induced tumor necrosis factor (TNF) and IL-12 p40 mRNA, but primed poorly for LPS-inducible p35 message and secreted IL-12 activity. Macrophage colony-stimulating factor (M-CSF), although a potent survival factor for monocytes, showed no priming activity for IL-12 production. Time course experiments demonstrated independent regulation of p40 and p35 by IFN-gamma and LPS. LPS inducibility of p40 expression required only a brief exposure to IFN-gamma (2 hours), while prolonged exposure (+/- 24 hours) to IFN-gamma resulted in diminishing levels of p40 mRNA. p35 inducibility (by LPS) required a longer exposure to IFN-gamma (8 to 16 hours), and continued to be inducible up to 40 hours following IFN- gamma priming. Both mRNAs were rapidly induced (1 to 2 hours) in IFN- gamma-primed monocytes; p35 message reached a plateau by 2 hours, while p40 continued to accumulate. Finally, both p40 and p35 were directly induced by LPS in the presence of cycloheximide. These results indicated that both p40 and p35 are LPS-inducible in monocytes following IFN-gamma pretreatment, and that the regulated expression of p35 controls the level of active IL-12 protein in purified human monocytes. The selectivity of priming by IFN-gamma is in accord with a putative role for IL-12 in the initiation and amplification of TH1-type responses. 相似文献