Publications by authors named "Levenson J"

Background: Relations of mediators of inflammation and hemostasis with preclinical atherosclerosis have been poorly analyzed. The aim of this study was to test potential associations of these blood markers with indicators of cardiovascular risk and atherosclerotic burden in asymptomatic, nonsmoking, hypercholesterolemic men.

Methods: A total of 87 men underwent cardiovascular risk assessment by means of 10-year Framingham risk calculation (median 9%) and atherosclerotic burden evaluation by means of ultrasonographic measurement of common carotid intima-media thickness and assessment of atherosclerotic plaques at three arterial sites (three-site plaques).

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Background: Enhanced external counterpulsation (EECP) is a noninvasive method previously shown to improve measures of myocardial ischemia in patients with coronary artery disease. However, the concomitant effects of EECP on large and small arterial properties have been poorly examined. In a randomized controlled study, we investigated whether arterial stiffness and resistance of the carotid circulation are altered by EECP.

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Serotonin reuptake inhibitors may increase symptoms of anxiety immediately following treatment initiation. The present study examined whether acute citalopram increased fear-potentiated startle to predictable and/or unpredictable shocks in healthy subjects. Eighteen healthy subjects each received two treatments, placebo and 20 mg citalopram in a crossover design.

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Traditional risk factors are poor screening tests for coronary heart disease, whereas clinical arterial disease represents its strongest predictor. This raises the question whether subclinical arterial disease may also predict coronary disease. Using published data of prospective studies of subclinical arterial disease, we calculated the incidence of coronary event associated with the absence or presence of atherosclerosis as defined by dichotomous characterization of the following markers: low or high intima-media thickness or the absence or presence of plaque, assessed by carotid ultrasound; zero or high total coronary artery calcium score assessed by computed tomography; normal or decreased ankle-arm index pressure assessed by Doppler stethoscope; and low or high aortic pulse wave velocity assessed by mecanography.

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Background: Enhanced external counterpulsation (EECP) is a noninvasive, pneumatic technique that provides favorable effects in patients with coronary artery disease and heart failure. The mechanisms by which EECP exerts its beneficial effects remain poorly understood. Cyclic GMP (cGMP) regulates vascular smooth muscle tone that may improve arterial function.

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Long-term memory formation is regulated by many distinct molecular mechanisms that control gene expression. An emerging model for effecting a stable, coordinated pattern of gene transcription involves epigenetic tagging through modifications of histones or DNA. In this study, we investigated the regulation of histone phosphorylation in the hippocampus by the ERK/MAPK (extracellular signal-regulated kinase/mitogen-activated protein kinase) pathway.

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An increasing amount of evidence suggests that the family of nuclear factor kappaB (NF-kappaB) transcription factors plays an important role in synaptic plasticity and long-term memory formation. The present study investigated the regulation of NF-kappaB family members p50, p65/RelA, and c-Rel in the hippocampus in response to metabotropic glutamate receptor (mGluR) signaling. Activation of group I metabotropic glutamate receptors (GpI-mGluRs) with the agonist (S)-3,5-dihydroxyphenylglycine (DHPG) resulted in a time-dependent increase in DNA binding activity of p50, p65, and c-Rel in area CA1 of the hippocampus.

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Objectives: To assess whether circulating endothelial progenitor cells (CEPCs) can be considered as a cardiovascular risk marker before event has occurred, that is less firmly established than in clinically overt atherosclerosis.

Methods: Number of CD34+KDR+ cell number per ml blood was measured by flow cytometry in 84 untreated subjects without cardiovascular disease. Atherosclerotic plaque was detected by ultrasound in carotid, abdominal aortic and femoral sites and the number of sites affected by plaque among these three sites was counted as 0, 1, 2 or 3.

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DNA (cytosine-5) methylation represents one of the most widely used mechanisms of enduring cellular memory. Stable patterns of DNA methylation are established during development, resulting in creation of persisting cellular phenotypes. There is growing evidence that the nervous system has co-opted a number of cellular mechanisms used during development to subserve the formation of long term memory.

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We address, both experimentally and theoretically, phase and amplitude dynamics of the electromagnetic field in a two-dimensional photonic crystal when femtosecond pulses are injected. We demonstrate that the usual adiabatic approximation underlying the dynamics of field and carriers in a semiconductor resonator is no longer valid, since in general the photon lifetime cannot be neglected with respect to the carrier recombination lifetime. Parameter regions where adiabaticity is broken are shown, and the ubiquity of the observed dynamical scenario in the new generation of active photonic microresonators is predicted.

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Despite continuing improvements in risk assessment for child protective services (CPS) and movement toward actuarial prediction of child maltreatment, current models have not adequately addressed child sexual abuse. Sexual abuse cases present unique and ambiguous indicators to the investigating professional, and risk factors differ from those related to physical abuse and neglect. Incorporation of research on risk factors specifically related to sexual offender recidivism into existing CPS risk assessment models may improve the ability to assess the risk of future sexual maltreatment to children.

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In this review we address the idea that conservation of epigenetic mechanisms for information storage represents a unifying model in biology, with epigenetic mechanisms being utilized for cellular memory at levels from behavioral memory to development to cellular differentiation. Epigenetic mechanisms typically involve alterations in chromatin structure, which in turn regulate gene expression. An emerging idea is that the regulation of chromatin structure through histone acetylation and DNA methylation may mediate long-lasting behavioral change in the context of learning and memory.

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Background: Many studies have found gender differences in frequency and intensity of pain. Women often report lower pain thresholds, higher pain ratings, and lower tolerance for pain. People with sickle cell disease (SCD) experience both chronic and acute pain throughout life.

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Objective: We examined the relationship between mental illness, health care utilization and rates of cholesterol testing.

Methods: We conducted a retrospective cohort study using Veterans Affairs (VA) administrative data on 64,490 United States veterans who used VA New England Health Care System outpatient services between January 1998 and June 2001. A total of 10,100 veterans (15.

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Loss-of-function mutations or abnormal expression of the X-linked gene encoding methyl CpG binding protein 2 (MeCP2) cause a spectrum of postnatal neurodevelopmental disorders including Rett syndrome (RTT), nonsyndromic mental retardation, learning disability, and autism. Mice expressing a truncated allele of Mecp2 (Mecp2(308)) reproduce the motor and social behavior abnormalities of RTT; however, it is not known whether learning deficits are present in these animals. We investigated learning and memory, neuronal morphology, and synaptic function in Mecp2(308) mice.

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Current possibilities for better detecting high risk of coronary heart disease (CHD) and stroke and peripheral arterial disease are described in this review. A first step is based on risk factors assessment that allows establishing high-risk diagnostic, either by detecting a condition termed as "CHD risk equivalent" and defined by one or more severe major risk factor, or by calculating multifactorial risk in asymptomatic subjects with a global risk score integrating several moderate risk factors. A second diagnostic step, concerning subjects not considered at high-risk by risk factors assessment, is based on non-invasive detection of sub clinical atherosclerosis via a wide variety of structural and functional arterial markers.

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Background: The effects of statins on intima-media thickness (IMT) are well documented, whereas those of fibrates are unknown. Therefore we compared IMT under treatment with each class of drugs.

Methods: We studied a cohort of consecutive dyslipidemic subjects treated with statin (n = 291) or fibrate (n = 82) drugs.

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We show that coherent population oscillations effect allows us to burn a narrow spectral hole (26 Hz) within the homogeneous absorption line of the optical transition of an erbium ion-doped crystal. The large dispersion of the index of refraction associated with this hole permits us to achieve a group velocity as low as 2.7 m/s with a transmission of 40%.

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The diagnosis of high risk of cardiovascular disease (CVD) in subjects without clinically overt CVD has been somewhat improved by integrating multiple traditional risk factors via appropriate risk score programs. Nevertheless, novel measures of CVD risk are being proposed and debated to further improve high-risk detection by their addition to, or their use in place of, traditional risk factors. Among such measures, non-invasive detection of subclinical arterial disease is a subject of growing interest.

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Background: Sickle cell disease (SCD) is a chronic disease associated with high degrees of morbidity and increased mortality. Health-related quality of life (HRQOL) among adults with sickle cell disease has not been widely reported.

Methods: We administered the Medical Outcomes Study 36-item Short-Form to 308 patients in the Pain in Sickle Cell Epidemiology Study (PiSCES) to assess HRQOL.

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Biofilm formation on surfaces is an ancient and integral strategy for bacterial survival. Billions of years of adaptation provide microbes with the ability to colonize any surface, including those used in orthopaedic surgery. Although remarkable progress has been made in the treatment of orthopaedic diseases with implanted prostheses, infection rates remain between 1% and 2%, and are higher for revision surgeries.

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Arterial sialic acid (SA) has been shown to attenuate the binding of fibrinogen and low-density lipoproteins (LDL) to the vessel wall, presumably protecting against atherosclerosis. This study was aimed to assess the effect of changes in SA content in intimal thickening, an early step in the development of atherosclerosis. New Zealand white rabbits were subjected to bilateral carotid periarterial collaring, followed by in situ-perfusion with neuroaminidase (random artery) and with vehicle (contralateral control artery).

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We studied 4,543 male physicians to assess accuracy of self-reported cholesterol level. The rate of accurate reporting improved over 14 years (25% to 62%), while failing to report a cholesterol level decreased. Overweight, current or past smoking, and physical inactivity were significantly associated with not reporting or inaccurately reporting cholesterol level.

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