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Palo Alto, CA, United States

Kimm S.Y.,Stanford University | Tarin T.V.,Stanford University | Lee J.H.,Stanford University | Hu B.,Stanford University | And 3 more authors.
Journal of Magnetic Resonance Imaging

Purpose: To evaluate two methods of scanning and tissue processing to achieve accurate magnetic resonance (MR)-histologic correlation in human prostate specimens. Materials and Methods: Two prostates had acrylic paint markers injected to define the plane of imaging and serve as internal fiducials. Each was placed on a polycarbonate plane-finder device (PFD), which was adjusted to align the imaging and cutting planes. Three prostates were aligned by use of a plane finder key (PFK), a polycarbonate plate that locks the specimen in a cylindrical carrier. Markers were injected for registration analysis. Prostates were imaged, then sectioned. Imaging software was used to create registration maps of the MR and histology images. Measurements between control points were made and compared. Results: Accurate correlation was achieved between MR and histologic images. The mean displacement (MD) between the corresponding registration points using the PFD technique ranged from 1.11-1.38 mm for each section. The MD for all sections was 1.24 mm. The MD using the PFK technique ranged from 0.79-1.01 mm for each section, and the MD across all sections for the PFK was 0.92 mm. Conclusion: We describe two methods that can achieve accurate, reproducible correlation between MR imaging and histologic sections in human prostatectomy specimens. © 2012 Wiley Periodicals, Inc. Source

Grant J.D.,University of Washington | Scherrer J.F.,University of Washington | Scherrer J.F.,Research Service 151 JC | Lynskey M.T.,University of Washington | And 6 more authors.
Alcoholism: Clinical and Experimental Research

Background: Although substance use is associated with reduced educational attainment, this association may be owing to common risk factors such as socioeconomic disadvantage. We tested whether alcohol, nicotine, and illicit drug use and dependence were associated with lifetime educational attainment after controlling for familial background characteristics. Methods: Data were from a 1987 questionnaire and a 1992 telephone diagnostic interview of 6,242 male twins (n = 3,121 pairs; mean age = 41.9 years in 1992) who served in the U.S. military during the Vietnam era and therefore, were eligible for educational benefits after military service. Reduced educational attainment (<16 years) was examined in twin pairs discordant for substance use history. Substance use and dependence risk factors assessed were early alcohol and cannabis use, daily nicotine use, lifetime cannabis use, and alcohol, nicotine, cannabis, and any illicit drug dependence. Results: Three significant differences were observed between at-risk twins and their cotwins: Compared to their low-risk cotwins, likelihood of completing <16 years of education was significantly increased for the following: (i) twins who used alcohol before age 18 (adjusted OR = 1.44; 95% CI: 1.02 to 2.05), (ii) twins with a lifetime alcohol dependence diagnosis (adjusted OR = 1.76; 95% CI: 1.27 to 2.44), and (iii) twins who had used nicotine daily for 30 or more days (adjusted OR = 2.54, 95% CI: 1.55 to 4.17). However, no differences in education were observed among twin pairs discordant for cannabis initiation, early cannabis use, or cannabis, nicotine, or any illicit drug dependence. Conclusions: Even in a veteran population with access to military educational benefits, early alcohol use, alcohol dependence, and daily nicotine use remained significantly associated with years of education after controlling for shared familial contributions to educational attainment. The association between other substances and educational attainment was explained by familial factors common to these substance use phenotypes and adult educational attainment. © 2012 by the Research Society on Alcoholism. Source

Yoluk O.,KTH Royal Institute of Technology | Bromstrup T.,KTH Royal Institute of Technology | Bromstrup T.,University of Stockholm | Bertaccini E.J.,Palo Alto Veterans Affairs Health Care System | And 3 more authors.
Biophysical Journal

Improving our understanding of the mechanisms and effects of anesthetics is a critically important part of neuroscience. The currently dominant theory is that anesthetics and similar molecules act by binding to Cys-loop receptors in the postsynaptic terminal of nerve cells and potentiate or inhibit their function. Although structures for some of the most important mammalian channels have still not been determined, a number of important results have been derived from work on homologous cationic channels in bacteria. However, partly due to the lack of a nervous system in bacteria, there are a number of questions about how these results relate to higher organisms. The recent determination of a structure of the eukaryotic chloride channel, GluCl, is an important step toward accurate modeling of mammalian channels, because it is more similar in function to human Cys-loop receptors such as GABAAR or GlyR. One potential issue with using GluCl to model other receptors is the presence of the large ligand ivermectin (IVM) positioned between all five subunits. Here, we have performed a series of microsecond molecular simulations to study how the dynamics and structure of GluCl change in the presence versus absence of IVM. When the ligand is removed, subunits move at least 2 Å closer to each other compared to simulations with IVM bound. In addition, the pore radius shrinks to 1.2 Å, all of which appears to support a model where IVM binding between subunits stabilizes an open state, and that the relaxed nonIVM conformations might be suitable for modeling other channels. Interestingly, the presence of IVM also has an effect on the structure of the important loop C located at the neurotransmitter-binding pocket, which might help shed light on its partial agonist behavior. © 2013 Biophysical Society. Source

Brooks III J.O.,University of California at Los Angeles | Hoblyn J.C.,Palo Alto Veterans Affairs Health Care System | Ketter T.A.,Stanford University
Psychiatry Research - Neuroimaging

Findings from previous research on the neural substrates of mania have been variable, in part because of heterogeneity of techniques and patients. Though some findings have been replicated, the constellation of neurophysiological changes has not been demonstrated simultaneously. We sought to determine resting state cerebral metabolic changes associated with relatively severe acute mania. Resting positron emission tomography with 18fluorodeoxyglucose was performed in bipolar disorder patients with severe mania and in healthy controls. Statistical parametric mapping was used to determine regions of differential metabolism. Relative to controls, bipolar disorder patients with mania exhibited significantly decreased cerebral metabolism in both the dorsolateral prefrontal regions and the precuneus. Conversely, manic patients exhibited significant hypermetabolism in the parahippocampal complex, temporal lobe, anterior cingulate, and subgenual prefrontal cortex compared with controls. These results demonstrate simultaneous resting limbic/paralimbic hypermetabolism and prefrontal hypometabolism during mania. The findings support the hypothesis of corticolimbic dysregulation as a crucial contributor to the pathophysiology of bipolar disorder. © 2009 Elsevier Ireland Ltd. Source

Robert P.H.,University of Nice Sophia Antipolis | Robert P.H.,Nice University Hospital Center | Konig A.,University of Nice Sophia Antipolis | Konig A.,Maastricht University | And 22 more authors.
Frontiers in Aging Neuroscience

Alzheimer's disease and other related disorders (ADRD) represent a major challenge for health care systems within the aging population. It is therefore important to develop better instruments to assess the disease severity and progression, as well as to improve its treatment, stimulation, and rehabilitation. This is the underlying idea for the development of Serious Games (SG). These are digital applications specially adapted for purposes other than entertaining; such as rehabilitation, training and education. Recently, there has been an increase of interest in the use of SG targeting patients with ADRD. However, this field is completely uncharted, and the clinical, ethical, economic and research impact of the employment of SG in these target populations has never been systematically addressed. The aim of this paper is to systematically analyze the Strengths, Weaknesses, Opportunities, and Threats (SWOT) of employing SG with patients with ADRD in order to provide practical recommendations for the development and use of SG in these populations. These analyses and recommendations were gathered, commented on and validated during a 2-round workshop in the context of the 2013 Clinical Trial of Alzheimer's Disease (CTAD) conference, and endorsed by stakeholders in the field. The results revealed that SG may offer very useful tools for professionals involved in the care of patients suffering from ADRD. However, more interdisciplinary work should be done in order to create SG specifically targeting these populations. Furthermore, in order to acquire more academic and professional credibility and acceptance, it will be necessary to invest more in research targeting efficacy and feasibility. Finally, the emerging ethical challenges should be considered a priority. © 2014 Robert, König, Amieva, Andrieu, Bremond, Bullock, Ceccaldi, Dubois, Gauthier, Kenigsberg, Nave, Orgogozo, Piano, Benoit, Touchon, Vellas, Yesavage and Manera. Source

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