Rush University Medical Center

About: Rush University Medical Center is a healthcare organization based out in Chicago, Illinois, United States. It is known for research contribution in the topics: Population & Dementia. The organization has 13915 authors who have published 29027 publications receiving 1379216 citations. The organization is also known as: Rush Presbyterian St. Luke's Medical Center.

Neurofibrillary Tangles Mediate the Association of Amyloid Load With Clinical Alzheimer Disease and Level of Cognitive Function

Abstract: Objective: To test the hypothesis that the association of amyloid load with clinical Alzheimer disease (AD) and cognitive impairment is mediated through neurofibrillary tangles. Design: Longitudinal clinicopathologic cohort study. Participants and Setting: Forty-four individuals with clinically diagnosed AD and 53 without dementia who participated in the Religious Orders Study underwent a uniform structured clinical evaluation for AD and cognitive testing about 8 months prior to death, and brain autopsy at death. Methods: The percent area occupied by amyloid- and the density of neurofibrillary tangles were quantified from 6 brain regions and averaged to yield summary measures of amyloid load and neurofibrillary tangles. Multivariate regression analyses were used to simultaneously examine the effects of amyloid load and neurofibrillary tangles on clinically diagnosed AD and level of cognition. Main Outcome Measures: Clinically diagnosed AD and level of global cognitive function proximate to death. Results: In separate logistic regression analyses, each 1% increase in amyloid load was associated with about a 50% increase in the odds of clinical AD (P=.002), and each neurofibrillary tangle was associated with a greater than 20% increase in the odds of clinical AD (P.001). When a term for tangles was added to the regression model with amyloid, the association of amyloid load with clinical disease was reduced by more than 60% and was no longer significant, whereas the association of tangles with clinical disease was essentially unchanged. Similar results were found in analyses of global cognitive function. Conclusion: These findings are consistent with a sequence of pathologic events whereby the effect of amyloid deposition on clinical disease is mediated by neurofibrillary tangles. Arch Neurol. 2004;61:378-384

Working Conditions in Primary Care: Physician Reactions and Care Quality

Abstract: Linzer and colleagues assessed the relationship among adverse primary care work conditions, adverse physician reactions, and quality of patient care. Among 422 family practitioners and general inte...

Summation priming and coarse semantic coding in the right hemisphere

Abstract: There are now numerous observations of subtle right hemisphere (RH) contributions to language comprehension. It has been suggested that these contributions reflect coarse semantic coding in the RH. That is, the RH weakly activates large semantic fields---including concepts distantly related to the input word---whereas the left hemisphere (LH) strongly activates small semantic fields---limited to concepts closely related to the input (Beeman, 1993a,b). This makes the RH less effective at interpreting single words, but more sensitive to semantic overlap of multiple words. To test this theory, subjects read target words preceded by either “Summation” primes (three words each weakly related to the target) or Unrelated primes (three unrelated words), and target exposure duration was manipulated so that subjects correctly named about half the target words in each hemifield. In Experiment 1, subjects benefited more from Summation primes when naming target words presented to the left visual field-RH (Ivf-RH) than when naming target words presented to the right visual field-LH (rvf-LH), suggesting a RH advantage in coarse semantic coding. In Experiment 2, with a low proportion of related prime-target trials, subjects benefited more from “Direct” primes (one strong associate flanked by two unrelated words) than from Summation primes for rvf-LH target words, indicating that the LH activates closely related information much more strongly than distantly related information. Subjects benefited equally from both prime types for Ivf-RH target words, indicating that the RH activates closely related information only slightly more strongly, at best, than distantly related information. This suggests that the RH processes words with relatively coarser coding than the LH, a conclusion consistent with a recent suggestion that the RH coarsely codes visual input (Kosslyn, Chabris, Mar-solek, & Koenig, 1992).

Perioperative Testing for Joint Infection in Patients Undergoing Revision Total Hip Arthroplasty

Abstract: Background: While multiple tests are used to determine the presence of infection at the site of a total hip arthroplasty, few studies have applied a consistent algorithm to determine the utility of the various tests that are available. The purpose of the present study was to evaluate the utility of commonly available tests for determining the presence of periprosthetic infection in patients undergoing revision total hip arthroplasty. Methods: Two hundred and thirty-five consecutive total hip arthroplasties in 220 patients were evaluated by one of two surgeons using a consistent algorithm to identify infection and were treated with reoperation. Receiver-operating-characteristic curve analysis was used to determine the optimal cut-point values for the white blood-cell count and the percentage of polymorphonuclear cells of intraoperatively aspirated hip synovial fluid. Sensitivity, specificity, negative predictive value, positive predictive value, and accuracy were determined. Patients were considered to have an infection if two of three criteria were met; the three criteria were a positive intraoperative culture, gross purulence at the time of reoperation, and positive histopathological findings. Results: Thirty-four arthroplasties were excluded because of the presence of a draining sinus, incomplete data, or a preoperative diagnosis of inflammatory arthritis, leaving 201 total hip arthroplasties available for evaluation. Fifty-five hips were judged to be infected. No hip in a patient with a preoperative erythrocyte sedimentation rate of 4200 white blood cells/mL for the white blood-cell count and >80% polymorphonuclear cells for the differential count. However, when combined with an elevated erythrocyte sedimentation rate and C-reactive protein level, the optimal cut-point for the synovial fluid cell count was >3000 white blood cells/mL, which yielded the highest combined sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the tests studied. Discussion: A synovial fluid cell count of >3000 white blood cells/mL was the most predictive perioperative testing modality in our study for determining the presence of periprosthetic infection when combined with an elevated preoperative erythrocyte sedimentation rate and C-reactive protein level in patients undergoing revision total hip arthroplasty. Level of Evidence: Diagnostic Level I. See Instructions to Authors for a complete description of levels of evidence.

Incidence and characteristics of pain in a sample of medical-surgical inpatients.

Abstract: The purposes of this study were to determine the incidence and characteristics of pain in hospitalized patients and to explore the type and perceived effectiveness of pharmacologic and nonpharmacologic therapies. Three hundred and fifty-three randomly selected patients reported experiencing pain during this hospitalization; 58% of these patients experienced excruciating pain. Fewer than half of the patients with pain had a member of the health care team ask them about their pain or note the pain in the patient record. The methods perceived as most effective in decreasing pain were analgesics, sleep, immobilization and distraction. As in earlier studies, the dose of analgesic administered over a 24-h period was less than a quarter of the amount ordered. This study concluded that (1) pain in hospitalized patients is more prevalent than has previously been reported, (2) patients with pain continue to receive inadequate dosages of analgesics, and (3) the identification and treatment of patients with pain remains a significant health care problem.