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81.
Interferon-alpha stimulates production of interleukin-10 in activated CD4+ T cells and monocytes 总被引:4,自引:1,他引:4
Aman MJ; Tretter T; Eisenbeis I; Bug G; Decker T; Aulitzky WE; Tilg H; Huber C; Peschel C 《Blood》1996,87(11):4731-4736
In the present study, we investigated the effect of interferon-alpha (IFN-alpha) on the expression of interleukin-10 (IL-10) mRNA and protein synthesis in human monocytes and CD4+ T cells. In mononuclear cells, IFN-alpha induced expression of IL-10 mRNA and further enhanced lipopolysaccharide (LPS)-stimulated IL-10 expression. In purified monocytes, a strong expression of IL-10 mRNA induced by LPS was not further enhanced by IFN-alpha. In highly purified CD4+ T cells, IFN- alpha upregulated IL-10 mRNA upon activation with phytohemagglutinin and phorbol myristate acetate. In purified monocytes, an effect of IFN- alpha on IL-10 protein synthesis was dependent on costimulation with LPS. Maximal stimulation of IL-10 protein by IFN-alpha was seen after prolonged incubation periods of 48 to 96 hours, whereas IFN-gamma reduced IL-10 production in the early incubation period. Similar effects of IFN-alpha were observed in CD4+ T cells activated with CD3 and CD28 monoclonal antibodies. Addition of IFN-alpha caused an increase of IL-10 in culture supernatants of activated T-helper cells of more than 100% after 96 hours of incubation. In contrast, other cytokines, including IFN-gamma and IL-4, had no influence on IL-10 secretion stimulated by CD3 and CD28 in CD4+ T cells. In serum samples of IFN-alpha-treated individuals, we failed to detect an influence of cytokine treatment on IL-10 serum levels, confirming the requirement of additional activating signals for IFN-alpha-mediated effects on IL-10 synthesis. In conclusion, IFN-alpha enhances the late induction of IL- 10, which physiologically occurs upon stimulation of monocytes and T cells. Biologically, this effect might enhance the negative-feedback mechanism ascribed to IL-10, which limits inflammatory reactions. 相似文献
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Jessica Kramer Amy Rubin Wendy Coster Eric Helmuth John Hermos David Rosenbloom Rich Moed Meghan Dooley Ying‐Chia Kao Kendra Liljenquist Deborah Brief Justin Enggasser Terence Keane Monica Roy Mark Lachowicz 《International journal of methods in psychiatric research》2014,23(1):120-129
Emerging methodological research suggests that the World Wide Web (“Web”) is an appropriate venue for survey data collection, and a promising area for delivering behavioral intervention. However, the use of the Web for research raises concerns regarding sample validity, particularly when the Web is used for recruitment and enrollment. The purpose of this paper is to describe the challenges experienced in two different Web‐based studies in which participant misrepresentation threatened sample validity: a survey study and an online intervention study. The lessons learned from these experiences generated three types of strategies researchers can use to reduce the likelihood of participant misrepresentation for eligibility in Web‐based research. Examples of procedural/design strategies, technical/software strategies and data analytic strategies are provided along with the methodological strengths and limitations of specific strategies. The discussion includes a series of considerations to guide researchers in the selection of strategies that may be most appropriate given the aims, resources and target population of their studies. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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David Cella Seung Choi Sofia Garcia Karon F. Cook Sarah Rosenbloom Jin-Shei Lai Donna Surges Tatum Richard Gershon 《Quality of life research》2014,23(10):2651-2661
Background
Although the use of patient-reported outcome measures (PROs) has increased markedly, clinical interpretation of scores remains lacking. We developed a method to identify clinical severity thresholds for pain, fatigue, depression, and anxiety in people with cancer.Methods
Using available Patient-Reported Outcomes Measurement Information System (PROMIS) item bank response data collected on 840 cancer patients, symptom vignettes across a range of symptom severity were developed and placed on index cards. Cards represented symptom severity at five-point intervals differences on the T score metric [mean = 50; standard deviation (SD) = 10]. Symptom vignettes for each symptom were anchored on these standardized scores at 0.5 SD increments across the full range of severity. Clinical experts, blind to the PROMIS score associated with each vignette, rank-ordered the vignettes by severity, then arrived at consensus regarding which two vignettes were at the upper and lower boundaries of normal and mildly symptomatic for each symptom. The procedure was repeated to identify cut scores separating mildly from moderately symptomatic, and moderately from severely symptomatic scores. Clinician severity rankings were then compared to the T scores upon which the vignettes were based.Results
For each of the targeted PROs, the severity rankings reached by clinician consensus perfectly matched the numerical rankings of their associated T scores. Across all symptoms, the thresholds (cut scores) identified to differentiate normal from mildly symptomatic were near a T score of 50. Cut scores differentiating mildly from moderately symptomatic were at or near 60, and those separating moderately from severely symptomatic were at or near 70.Conclusions
The study results provide empirically generated PROMIS T score thresholds that differentiate levels of symptom severity for pain interference, fatigue, anxiety, and depression. The convergence of clinical judgment with self-reported patient severity scores supports the validity of this methodology to derive clinically relevant symptom severity levels for PROMIS symptom measures in other settings. 相似文献85.
Adolf Pfefferbaum David A. Rogosa Margaret J. Rosenbloom Weiwei Chu Stephanie A. Sassoon Carol A. Kemper Stanley Deresinski Torsten Rohlfing Natalie M. Zahr Edith V. Sullivan 《Neurobiology of aging》2014
Advances in treatment have transformed human immunodeficiency virus (HIV) infection from an inexorable march to severe morbidity and premature death to a manageable chronic condition, often marked by good health. Thus, infected individuals are living long enough that there is a potential for interaction with normal senescence effects on various organ systems, including the brain. To examine this interaction, the brains of 51 individuals with HIV infection and 65 uninfected controls were studied using 351 magnetic resonance imaging and a battery of neuropsychological tests collected 2 or more times over follow-up periods ranging from 6 months to 8 years. Brain tissue regions of interest showed expected age-related decrease in volume; cerebrospinal fluid-filled spaces showed increase in volume for both groups. Although HIV-infected individuals were in good general health, and free of clinically-detectable dementia, several brain regions supporting higher-order cognition and integration of functions showed acceleration of the normal aging trajectory, including neocortex, which extended from the frontal and temporal poles to the parietal lobe, and the thalamus. Beyond an anticipated increase in lateral ventricle and Sylvian fissure volumes and decrease in tissue volumes (specifically, the frontal and sensorimotor neocortices, thalamus, and hippocampus) with longer duration of illness, most regions also showed accelerated disease progression. This accelerated loss of cortical tissue may represent a risk factor for premature cognitive and motor compromise if not dementia. On a more promising note, HIV-infected patients with increasing CD4 counts exhibited slower expansion of Sylvian fissure volume and slower declines of frontal and temporoparietal cortices, insula, and hippocampus tissue volumes. Thus, attenuated shrinkage of these brain regions, likely with adequate pharmacologic treatment and control of further infection, has the potential of abating decline in associated higher-order functions, notably, explicit memory, executive functions, self-regulation, and visuospatial abilities. 相似文献
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J C Laschinger M W Vannier S Gronemeyer F Gutierrez M Rosenbloom J L Cox 《The Annals of thoracic surgery》1988,45(5):505-514
We have developed a new method of computer image processing that allows true three-dimensional (3-D) images of the heart and great vessels to be reconstructed from standard ECG-gated two-dimensional magnetic resonance (MR) images. Contiguous 5-mm thick MR images of the thorax from the level of the cardiac apex to the aortic arch were obtained in 4 normal volunteers and 3 patients with congenital heart disease: 1 with pseudotruncus arteriosus and 1 with a ventricular septal defect, each with Eisenmenger's complex, and 1 with aortic coarctation. Each image could be obtained at up to seven different intervals throughout the cardiac cycle with ECG gating. The scanning procedure is noninvasive and requires no contrast material. Using standard software, images from each interval in the cardiac cycle were edited to isolate pertinent cardiac and great vessel structures. High-resolution 3-D reconstructions were formed for each interval by stacking the edited images. Sequential projection of 3-D reconstructions from each interval yields four-dimensional (includes time) cine views. Both 3-D and cine views can be obtained from any axis or divided in any plane to allow accurate, noninvasive assessment of cardiac and great vessel anatomy, chamber volumes, and regional and global wall motion. Noninvasive 3-D reconstruction of the heart and great vessels provides accurate anatomical data not available from standard cardiac catheterization or other noninvasive diagnostic procedures, and aids in the preoperative planning of the procedure to correct complex congenital malformations. 相似文献
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