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121.
Yader Sandoval Stephen W. Smith Anne Sexter Sarah E. Thordsen Charles A. Bruen Michelle D. Carlson Kenneth W. Dodd Brian E. Driver Yan Hu Katherine Jacoby Benjamin K. Johnson Sara A. Love Johanna C. Moore Karen Schulz Nathaniel L. Scott Fred S. Apple 《The American journal of medicine》2017,130(12):1431-1439.e4
Background
Studies addressing patients with type 2 myocardial infarction and myocardial injury, including the impact of using high-sensitivity (hs) cardiac troponin (cTn) assays on their incidence are needed.Methods
Ours is a prospective, observational US cohort study. Consecutive emergency department patients with serial cTnI measurements were studied. Outcomes included 180-day mortality and major adverse cardiac events, including 2-year follow-up for those with myonecrosis.Results
Among 1640 patients, using a contemporary cTnI assay, 30% (n = 497) had ≥1 cTnI >99th percentile, with 4.7% (n = 77), 8.5% (n = 140), and 17% (n = 280) classified as type 1 myocardial infarction, type 2 myocardial infarction, and myocardial injury, respectively. Compared with patients without myonecrosis, 180-day mortality was higher for type 2 myocardial infarction (4% vs 13%, P < .0001) (adjusted hazard ratio 2.7; 95% confidence interval, 1.6-4.8; P = .0005) and myocardial injury (4% vs 11%, P < .0001) (adjusted hazard ratio 1.8; 95% confidence interval, 1.1-3.0; P = .02), both with mortality >20% at 2 years. Predictors of 2-year mortality for type 2 myocardial infarction included age, congestive heart failure, and beta-blockers. Relative to the contemporary cTnI assay, hs-cTnI had less myonecrosis (30% vs 26%, P = .003) and acute myocardial infarction (13.2% vs 10.8%, P = .032), including fewer type 2 myocardial infarctions (8.5% vs 6.3, P = .01), with no difference in myocardial injury (17% vs 15%, P = .1).Conclusions
cTnI increases are encountered in approximately a third of patients, the majority due to nonatherothrombotic conditions. Compared with patients without myonecrosis, type 2 myocardial infarction and myocardial injury have worse short-term outcomes, with mortality rates >20% at 2 years. hs-cTnI assay does not lead to more myocardial injury or infarction. 相似文献122.
Yang XR Chang-Claude J Goode EL Couch FJ Nevanlinna H Milne RL Gaudet M Schmidt MK Broeks A Cox A Fasching PA Hein R Spurdle AB Blows F Driver K Flesch-Janys D Heinz J Sinn P Vrieling A Heikkinen T Aittomäki K Heikkilä P Blomqvist C Lissowska J Peplonska B Chanock S Figueroa J Brinton L Hall P Czene K Humphreys K Darabi H Liu J Van 't Veer LJ van Leeuwen FE Andrulis IL Glendon G Knight JA Mulligan AM O'Malley FP Weerasooriya N John EM Beckmann MW Hartmann A Weihbrecht SB Wachter DL Jud SM 《Journal of the National Cancer Institute》2011,103(3):250-263
123.
John N. Caviness MD Lih‐Fen Lue PhD Thomas G. Beach MD PhD Joseph G. Hentz MS Charles H. Adler MD PhD Lucia Sue Ramin Sadeghi Erika Driver‐Dunckley MD Virgilio G. Evidente MD Marwan N. Sabbagh MD Holly A. Shill MD Douglas G. Walker PhD 《Movement disorders》2011,26(8):1436-1442
The ability to understand how Parkinson's disease neurodegeneration leads to cortical dysfunction will be critical for developing therapeutic advances in Parkinson's disease dementia. The overall purpose of this project was to study the small‐amplitude cortical myoclonus in Parkinson's disease as an in vivo model of focal cortical dysfunction secondary to Parkinson's disease neurodegeneration. The objectives were to test the hypothesis that cortical myoclonus in Parkinson's disease is linked to abnormal levels of α‐synuclein in the primary motor cortex and to define its relationship to various biochemical, clinical, and pathological measures. The primary motor cortex was evaluated for 11 Parkinson's disease subjects with and 8 without electrophysiologically confirmed cortical myoclonus (the Parkinson's disease + myoclonus group and the Parkinson's disease group, respectively) who had premortem movement and cognitive testing. Similarly assessed 9 controls were used for comparison. Measurements for α‐synuclein, Aβ‐42 peptide, and other biochemical measures were made in the primary motor cortex. A 36% increase in α‐synuclein was found in the motor cortex of Parkinson's disease + myoclonus cases when compared with Parkinson's disease without myoclonus. This occurred without significant differences in insoluble α‐synuclein, phosphorylated to total α‐synuclein ratio, or Aβ‐42 peptide levels. Higher total motor cortex α‐synuclein levels significantly correlated with the presence of cortical myoclonus but did not correlate with multiple clinical or pathological findings. These results suggest an association between elevated α‐synuclein and the dysfunctional physiology arising from the motor cortex in Parkinson's disease + myoclonus cases. Alzheimer's disease pathology was not associated with cortical myoclonus in Parkinson's disease. Cortical myoclonus arising from the motor cortex is a model to study cortical dysfunction in Parkinson's disease. © 2011 Movement Disorder Society 相似文献
124.
125.
Geng JJ Eger E Ruff CC Kristjánsson A Rotshtein P Driver J 《Journal of neurophysiology》2006,96(5):2601-2612
We used fMRI to investigate competition and on-line attentional selection between targets and distractors in opposite visual hemifields. Displays comprised a high-contrast square-wave grating, defined as target by its orientation, presented alone (unilateral) or with a similar distractor of orthogonal orientation in the opposite hemifield (bilateral displays). The target appeared unpredictably on the left or right, precluding anticipatory attention to one side. We found greater activation in target-contralateral superior occipital gyrus for unilateral than for bilateral displays, indicating suppression of the target's visual representation by distractor presence despite the competing distractor projecting to a different occipital hemisphere. Several frontal and parietal regions showed greater activation for bilateral than unilateral trials, suggesting involvement in on-line attentional selection. This was particularly pronounced for regions in bilateral intraparietal sulcus (IPS), which also showed greater functional coupling with occipital cortex specifically on bilateral trials that required selection plus some repetition-suppression effects when target side was repeated, but again only on bilateral trials requiring selection. Our results indicate that competition between visual stimuli in opposite hemifields can influence occipital cortex, and implicate IPS in resolution of this competition by selection. 相似文献
126.
Ross J Chester G Driver J Lunchick C Holden L Rosenheck L Barnekow D 《Journal of exposure science & environmental epidemiology》2008,18(2):211-230
Passive dosimetry (PD) methods for measuring and estimating exposure to agricultural workers (i.e., persons handling agricultural chemicals and working in treated crops) have been in use since the 1950s. A large number of studies were conducted in the 1950s through 1970s to characterize exposure. Since the 1980s quantitative dermal PD methods are used in conjunction with inhalation PD methods to measure whole-body exposure. These exposure or absorbed dose estimates are then compared to "no effect" exposure levels for hazards identified in toxicology studies, and have become the standard for risk assessment for regulatory agencies. The PD methods used have never been validated. Validation in the context of human exposure monitoring methods means that a method has been shown to measure accurately a delivered dose in humans. The most practical alternative to isolating parts of the body for validating recovery methods is to utilize field exposure studies in which concurrent or consecutive measurements of exposure and absorbed dose have been made with PD and biomonitoring in the same cohorts of individuals. This ensures that a direct comparison can be made between the two estimates of absorbed dose, one derived from PD and the other from biomonitoring. There are several studies available (published and proprietary) employing both of these approaches. Reports involving 14 concurrent or consecutive PD-biomonitoring studies were quantitatively evaluated with 18 different methods of application or reentry scenarios for eight different active ingredients for which measured human kinetics and dermal absorption data existed. This evaluation demonstrated that the total absorbed dose estimated using PD for important handler and reentry scenarios is generally similar to the measurements for those same scenarios made using human urinary biomonitoring methods. The statistical analysis of individual worker PD:biomonitoring ratios showed them to be significantly correlated in these studies. The PD techniques currently employed yield a reproducible, standard methodology that is valid and reliably quantifies exposure. 相似文献
127.
Nanthakumaran S Inam I Neefjes V Driver CP Youngson GG 《Pediatric surgery international》2008,24(4):481-483
Limitations exist with the use of computer tomography (CT) in evaluating tumour recurrence at the site of previous chest wall
reconstruction due to poor differentiation between inflammatory change and tumour recurrence. This case highlights the value
of combined positron emission tomography and CT, which generates detailed anatomical and metabolic profiles in this diagnostic
dilemma. 相似文献
128.
Alexander E. Sherman Gabriela Motyckova K. Rebecca Fega Daniel J. DeAngelo Gregory A. Abel David Steensma Martha Wadleigh Richard M. Stone Jane A. Driver 《Leukemia research》2013
We explored whether geriatric assessment variables predicted mortality in addition to known prognostic factors in 101 patients aged ≥65 with newly diagnosed AML. Baseline comorbidity score (HR = 1.92; 95%CI 1.18–3.11), difficulty with strenuous activity (HR = 2.18; 95%CI 1.19–4.00), and pain (HR = 2.17; 95%CI 1.19–3.97) were independent prognostic factors for greater risk of death in a multivariable model that included cytogenetic risk group. They remained independent predictors in the subset of patients with baseline ECOG PS 0-1. Our results support the use of geriatric assessment to better predict prognosis in older patients with AML, even among those with excellent functional status. 相似文献
129.
130.
Visual perception depends not only on local stimulus features but also on their relationship to the surrounding stimulus context, as evident in both local and contextual influences on figure-ground segmentation. Intermediate visual areas may play a role in such contextual influences, as we tested here by examining LG, a rare case of developmental visual agnosia. LG has no evident abnormality of brain structure and functional neuroimaging showed relatively normal V1 function, but his intermediate visual areas (V2/V3) function abnormally. We found that contextual influences on figure-ground organization were selectively disrupted in LG, while local sources of figure-ground influences were preserved. Effects of object knowledge and familiarity on figure-ground organization were also significantly diminished. Our results suggest that the mechanisms mediating contextual and familiarity influences on figure-ground organization are dissociable from those mediating local influences on figure-ground assignment. The disruption of contextual processing in intermediate visual areas may play a role in the substantial object recognition difficulties experienced by LG. 相似文献