Publications by authors named "O'Keefe J"

Place cells in hippocampal area CA1 are essential for spatial learning and memory. Here, we examine whether daily exposure to a previously unexplored environment can alter place cell properties. We demonstrate two previously unreported slowly developing plasticities in mouse place fields: both the spatial tuning and the trial-to-trial reproducibility of CA1 place fields improve over days.

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We expand upon our proposal that the oscillatory interference mechanism proposed for the phase precession effect in place cells underlies the grid-like firing pattern of dorsomedial entorhinal grid cells (O'Keefe and Burgess (2005) Hippocampus 15:853-866). The original one-dimensional interference model is generalized to an appropriate two-dimensional mechanism. Specifically, dendritic subunits of layer II medial entorhinal stellate cells provide multiple linear interference patterns along different directions, with their product determining the firing of the cell.

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A real-time polymerase chain reaction (PCR) assay was developed for detection of the presence of bovine herpesvirus type 1 (BoHV-1) in extended bovine semen. The assay detects a region encoding a highly conserved glycoprotein B gene. The real-time PCR assay was validated for specificity, sensitivity and repeatability using spiked semen and semen from naturally infected animals.

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Background: The Epleronone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival Study (EPHESUS) trial demonstrated that selective aldosterone blockade with eplerenone significantly reduced total mortality by 15%, combined cardiovascular (CV) mortality/CV hospitalization by 13%, CV mortality by 17% and sudden cardiac death by 21%, vs. placebo when added to standard care in patients with left ventricular systolic dysfunction (LVSD) and signs of congestive heart failure (CHF) following acute myocardial infarction (AMI). We retrospectively evaluated the effect of eplerenone vs.

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Background: Diabetes mellitus (DM) is a common comorbidity among patients with acute coronary syndrome (ACS). The frequency with which physicians assess diabetic patients' glycemic control during an ACS hospitalization is not known and may represent an opportunity for quality improvement.

Methods: This study describes the proportion of diabetic patients who had an assessment of their glycemic control (HbA1c) at the time of an ACS hospitalization.

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The current epidemic of obesity warrants aggressive screening for associated comorbid conditions; namely, the metabolic syndrome and diabetes mellitus. Approximately 25-30% of patients with acute coronary syndrome have diabetes. Of the remaining patients, most have a spectrum of abnormal glucose metabolism, including previously undiagnosed impaired fasting glucose and diabetes mellitus.

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Memory CD8(+) T cell responses are thought to be more effective as a result of both a higher frequency of Ag-specific clones and more rapid execution of effector functions such as granule-mediated lysis. Murine models have indicated that memory CD8(+) T cells exhibit constitutive expression of perforin and can lyse targets directly ex vivo. However, the regulated expression of cytotoxic granules in human memory CD8(+) T cell subsets has been underexplored.

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Clinically and experimentally, primary tumor formation and metastasis are distinct processes — locally growing tumors can progress without the development of metastases. This observation prompted the hypothesis that the molecular processes regulating tumorigenicity and metastasis are distinguishable and could be targeted therapeutically. During the process of transformation and subsequent progression to a malignant phenotype, both genetic and epigenetic alterations alter a cell’s ability to perceive and respond to signals that regulate normal tissue homeostasis.

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This editorial outlines the data supporting aggressive lipid goals and options for treating low-density lipoprotein (LDL) cholesterol to a range of approximately 30 to 70 mg/dl. The physiologically normal cholesterol range is approximately 30 to 70 mg/dl for native hunter-gatherers, healthy human neonates, free-living primates, and virtually all wild mammals. Randomized statin trials in patients with recent acute coronary syndromes and stable coronary artery disease have demonstrated that cardiovascular events are reduced and cardiovascular survival optimized when LDL cholesterol is reduced to <70 mg/dl.

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Many mammals spontaneously rear on their hind legs in response to novelty. The current paper is the first review of rearing behaviour, and is intended to collate findings from different perspectives that are not usually brought together. We suggest that rearing is a useful marker of environmental novelty, that the hippocampal formation is a crucial component of the system controlling rearing in novel environments, and that rearing is one of several ethological measures that can profitably be used to assess hippocampal learning and memory.

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We review evidence for the boundary vector cell model of the environmental determinants of the firing of hippocampal place cells. Preliminary experimental results are presented concerning the effects of addition or removal of environmental boundaries on place cell firing and evidence that boundary vector cells may exist in the subiculum. We review and update computational simulations predicting the location of human search within a virtual environment of variable geometry, assuming that boundary vector cells provide one of the input representations of location used in mammalian spatial memory.

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This article will detail how the Kaiser Permanente Healthcare Organization responded to the 2000 Institute of Medicine's report which cited statistics regarding patient safety and the cost and consequences of medical errors. It will then reveal the important role Kaiser Permanente's Employee and Physician Assistance Program serves in support of Kaiser's patient care providers who are working to reduce the medical errors that lead to adverse outcomes. While striving to increase patient safety, Kaiser Permanente's Responsible Reporting and Accountability Policy will be reviewed, with a primary focus on the components of the policy which describes how the Employee and Physician Assistance Program utilizes a model of support intended to maintain and restore the functioning and well-being of Kaiser Permanente's patient care providers.

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We explored possible mechanisms by which recommended intakes of omega-3 fatty acids may decrease the risk for sudden cardiac death in patients with documented coronary heart disease. The cardioprotective effects of omega-3 fatty acids have been documented in epidemiologic and randomized controlled trials. These fatty acids are presumed to decrease susceptibility to fatal arrhythmias, but whether this is mediated by classic risk factors or direct cardiac mechanisms is not known.

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Measuring and monitoring performance--be it waiting list and posttransplant outcomes by a transplant center, or organ donation success by an organ procurement organization and its partnering hospitals--is an important component of ensuring good care for people with end-stage organ failure. Many parties have an interest in examining these outcomes, from patients and their families to payers such as insurance companies or the Centers for Medicare and Medicaid Services; from primary caregivers providing patient counseling to government agencies charged with protecting patients. The Scientific Registry of Transplant Recipients produces regular, public reports on the performance of transplant centers and organ procurement organizations.

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Aim: To genotype bovine herpesvirus type 1 (BHV-1) isolates from cattle in New Zealand.

Methods: Twenty-eight BHV-1 isolates were collected from clinical samples from cattle over 28 years. They were characterised and compared using restriction endonuclease analysis (REA), and polymerase chain reaction (PCR) and DNA sequencing.

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This study surveyed all cardiologists in a large coalition of cardiology groups. A 1-page, 25-item anonymous questionnaire containing 3 sections (demographics, medical history, and current medications and supplements) was used. Data from returned questionnaires were analyzed and compared with those in national databases.

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Aim: To determine the diagnostic capability of a newly developed Western blot (WB) assay for the detection of serum antibodies against Mycoplasma agalactiae compared with conventional serological tests, and to identify the best test for routine diagnostic use.

Methods: The serological test methods used were: two commercial indirect enzyme-linked immunosorbent assays (ELISA), viz ELISA-1, using a bacterial antigen preparation, and ELISA-2, using a recombinant protein (lipoprotein p48) antigen; the complement fixation test (CFT); and a newly developed WB assay, the latter both using a bacterial antigen preparation. Thirty sera from goats infected with M.

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Psychosocial stress exerts independent adverse effects on cardiovascular health. The recent INTERHEART study reported that psychosocial stress accounted for approximately 30% of the attributable risk of acute myocardial infarction. Prospective studies consistently indicate that hostility, depression, and anxiety are all related to increased risk of coronary heart disease and cardiovascular death.

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Recruitment of adolescents into tobacco use research is often challenging. This study reports on the predictors of recruitment and retention in a longitudinal study of adolescent smoking behavior. In 2000, 8th and 10th grade students at 18 schools (N = 5,298) in the Chicago metropolitan area completed brief screening surveys; 1457 students (ranging from susceptible nonsmokers to regular smokers) were invited to participate in a longitudinal study, and 48.

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Aim: To conduct a longitudinal serological survey for evidence of Brucella spp and Leptospira spp infection of pre-weaned New Zealand fur seals in a colony on the Otago Peninsula.

Methods: Seal pups were repeatedly captured on a monthly basis from February through to July 2001. Pups were tagged at first capture and a blood sample was taken at each capture event.

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