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https://www.readbyqxmd.com/read/27903933/translocator-positron-emission-tomography-and-magnetic-resonance-spectroscopic-imaging-of-brain-glial-cell-activation-in-multiple-sclerosis
#1
Gourab Datta, Ines R Violante, Gregory Scott, Karl Zimmerman, Andre Santos-Ribeiro, Eugenii A Rabiner, Roger N Gunn, Omar Malik, Olga Ciccarelli, Richard Nicholas, Paul M Matthews
BACKGROUND: Multiple sclerosis (MS) is characterised by a diffuse inflammatory response mediated by microglia and astrocytes. Brain translocator protein (TSPO) positron-emission tomography (PET) and [myo-inositol] magnetic resonance spectroscopy (MRS) were used together to assess this. OBJECTIVE: To explore the in vivo relationships between MRS and PET [(11)C]PBR28 in MS over a range of brain inflammatory burden. METHODS: A total of 23 patients were studied...
November 30, 2016: Multiple Sclerosis: Clinical and Laboratory Research
https://www.readbyqxmd.com/read/27903921/a-two-pool-model-to-describe-the-ivim-cerebral-perfusion
#2
Gabrielle Fournet, Jing-Rebecca Li, Alex M Cerjanic, Bradley P Sutton, Luisa Ciobanu, Denis Le Bihan
IntraVoxel Incoherent Motion (IVIM) is a magnetic resonance imaging (MRI) technique capable of measuring perfusion-related parameters. In this manuscript, we show that the mono-exponential model commonly used to process IVIM data might be challenged, especially at short diffusion times. Eleven rat datasets were acquired at 7T using a diffusion-weighted pulsed gradient spin echo sequence with b-values ranging from 7 to 2500 s/mm(2) at three diffusion times. The IVIM signals, obtained by removing the diffusion component from the raw MR signal, were fitted to the standard mono-exponential model, a bi-exponential model and the Kennan model...
November 30, 2016: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/27903187/stereotactic-diffusion-tensor-imaging-tractography-for-gamma-knife-radiosurgery
#3
Cormac G Gavin, H Ian Sabin
OBJECTIVE The integration of modern neuroimaging into treatment planning has increased the therapeutic potential and safety of stereotactic radiosurgery. The authors report their method of integrating stereotactic diffusion tensor imaging (DTI) tractography into conventional treatment planning for Gamma Knife radiosurgery (GKRS). The aim of this study was to demonstrate the feasibility of this technique and to address some of the technical limitations of previously reported techniques. METHODS Twenty patients who underwent GKRS composed the study cohort...
December 2016: Journal of Neurosurgery
https://www.readbyqxmd.com/read/27902865/small-world-properties-changes-in-mild-traumatic-brain-injury
#4
Yongxia Zhou
PURPOSE: To investigate local and global efficiency changes characterized by small-world properties based on resting-state functional MRI, such as centrality and clustering coefficient, in mild traumatic brain injury (MTBI) patients; and to associate these findings with axonal injury as measured by diffusion tensor imaging (DTI) as well as with post-concussive symptom (PCS). MATERIALS AND METHODS: Thirty patients (mean age 35 ± 13 years) with clinically defined MTBI and 45 age-matched healthy controls (mean age 37 ± 10 years) participated in the experiments...
November 30, 2016: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/27902245/streptomyces-luteus-sp-nov-a-novel-actinomycete-isolated-from-loulan-soil-of-xinjiang-china
#5
Xiaoxia Luo, Kai Liang, Yang Wang, Chuanxing Wan, Lili Zhang
A Streptomyces strain, designated TRM 45540T, was isolated from the soil of Loulan area(89°22'22″E, 40°29'55″N), Xinjiang Province, north-west China and was characterized taxonomically by using a polyphasic study. Phylogenetic analysis of the strain from 16S rRNA sequence revealed the strain TRM 45540 had 99.87% similarity with the type strain Streptomyces mutabilis NRRL12800T (GenBank accession number. AB184156). The strain was aerobic, gram-staining-positive, with an optimum NaCl concentration for growth of 5% (w/v)...
November 1, 2016: International Journal of Systematic and Evolutionary Microbiology
https://www.readbyqxmd.com/read/27900365/genome-sequencing-in-a-case-of-niemann-pick-type-c
#6
Max Dougherty, John Lazar, Jason C Klein, Karina Diaz, Theodore Gobillot, Eli Grunblatt, Nicholas Hasle, Daniel Lawrence, Megan Maurano, Maria Nelson, Gregory Olson, Sanjay Srivatsan, Jay Shendure, C Dirk Keene, Thomas Bird, Marshall S Horwitz, Desiree A Marshall
Adult-onset Niemann-Pick disease type C (NPC) is an infrequent presentation of a rare neurovisceral lysosomal lipid storage disorder caused by autosomal recessive mutations in NPC1 (∼95%) or NPC2 (∼5%). Our patient was diagnosed at age 33 when he presented with a 10-yr history of difficulties in judgment, concentration, speech, and coordination. A history of transient neonatal jaundice and splenomegaly with bone marrow biopsy suggesting a lipid storage disorder pointed to NPC; biochemical ("variant" level cholesterol esterification) and ultrastructural studies in adulthood confirmed the diagnosis...
November 2016: Cold Spring Harbor Molecular Case Studies
https://www.readbyqxmd.com/read/27898701/assessing-white-matter-microstructure-in-brain-regions-with-different-myelin-architecture-using-mri
#7
Samuel Groeschel, Gisela E Hagberg, Thomas Schultz, Dávid Z Balla, Uwe Klose, Till-Karsten Hauser, Thomas Nägele, Oliver Bieri, Thomas Prasloski, Alex L MacKay, Ingeborg Krägeloh-Mann, Klaus Scheffler
OBJECTIVE: We investigate how known differences in myelin architecture between regions along the cortico-spinal tract and frontal white matter (WM) in 19 healthy adolescents are reflected in several quantitative MRI parameters that have been proposed to non-invasively probe WM microstructure. In a clinically feasible scan time, both conventional imaging sequences as well as microstructural MRI parameters were assessed in order to quantitatively characterise WM regions that are known to differ in the thickness of their myelin sheaths, and in the presence of crossing or parallel fibre organisation...
2016: PloS One
https://www.readbyqxmd.com/read/27898201/diffusion-weighted-imaging-of-the-abdomen-impact-of-b-values-on-texture-analysis-features
#8
Anton S Becker, Matthias W Wagner, Moritz C Wurnig, Andreas Boss
The purpose of this work was to systematically assess the impact of the b-value on texture analysis in MR diffusion-weighted imaging (DWI) of the abdomen. In eight healthy male volunteers, echo-planar DWI sequences at 16 b-values ranging between 0 and 1000 s/mm(2) were acquired at 3 T. Three different apparent diffusion coefficient (ADC) maps were computed (0, 750/100, 390, 750 s/mm(2) /all b-values). Texture analysis of rectangular regions of interest in the liver, kidney, spleen, pancreas, paraspinal muscle and subcutaneous fat was performed on DW images and the ADC maps, applying 19 features computed from the histogram, grey-level co-occurrence matrix (GLCM) and grey-level run-length matrix (GLRLM)...
November 29, 2016: NMR in Biomedicine
https://www.readbyqxmd.com/read/27896958/when-should-we-not-transfer-functional-annotation-between-sequence-paralogs
#9
Mengfei Cao, Lenore J Cowen
Current automated computational methods to assign functional labels to unstudied genes often involve transferring annotation from orthologous or paralogous genes, however such genes can evolve divergent functions, making such transfer inappropriate. We consider the problem of determining when it is correct to make such an assignment between paralogs. We construct a benchmark dataset of two types of similar paralogous pairs of genes in the well-studied model organism S. cerevisiae: one set of pairs where single deletion mutants have very similar phenotypes (implying similar functions), and another set of pairs where single deletion mutants have very divergent phenotypes (implying different functions)...
2016: Pacific Symposium on Biocomputing
https://www.readbyqxmd.com/read/27891585/novel-mutations-in-kars-cause-hypertrophic-cardiomyopathy-and-combined-mitochondrial-respiratory-chain-defect
#10
Daniela Verrigni, Daria Diodato, Michela Di Nottia, Alessandra Torraco, Emanuele Bellacchio, Teresa Rizza, Giulia Tozzi, Margherita Verardo, Fiorella Piemonte, Giorgio Tasca, Adele D'Amico, Enrico Bertini, Rosalba Carrozzo
Mutations in KARS, which encodes for both mitochondrial and cytoplasmic lysyl-tRNA synthethase, have been so far associated with three different phenotypes: the recessive form of Charcot Mary-Tooth polyneuropathy, the autosomal recessive non-syndromic hearing loss and the last recently described condition related to congenital visual impairment and progressive microcephaly. Here we report the case of a 14-years-old-girl with severe cardiomyopathy associated to mild psychomotor delay and mild myopathy; moreover, a diffuse reduction of cytochrome C oxidase (COX, complex IV) and a combined enzymatic defect of complex I (CI) and IV (CIV) was evident in muscle biopsy...
November 28, 2016: Clinical Genetics
https://www.readbyqxmd.com/read/27891144/a-developmental-and-molecular-view-of-formation-of-auxin-induced-nodule-like-structures-in-land-plants
#11
Ryan Hiltenbrand, Jacklyn Thomas, Hannah McCarthy, Karl J Dykema, Ashley Spurr, Hamilton Newhart, Mary E Winn, Arijit Mukherjee
Several studies have shown that plant hormones play important roles during legume-rhizobia symbiosis. For instance, auxins induce the formation of nodule-like structures (NLSs) on legume roots in the absence of rhizobia. Furthermore, these NLS can be colonized by nitrogen-fixing bacteria, which favor nitrogen fixation compared to regular roots and subsequently increase plant yield. Interestingly, auxin also induces similar NLS in cereal roots. While several genetic studies have identified plant genes controlling NLS formation in legumes, no studies have investigated the genes involved in NLS formation in cereals...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27889022/advanced-mr-imaging-in-pediatric-brain-tumors-clinical-applications
#12
REVIEW
Maarten Lequin, Jeroen Hendrikse
Advanced MR imaging techniques, such as spectroscopy, perfusion, diffusion, and functional imaging, have improved the diagnosis of brain tumors in children and also play an important role in defining surgical as well as therapeutic responses in these patients. In addition to the anatomic or structural information gained with conventional MR imaging sequences, advanced MR imaging techniques also provide physiologic information about tumor morphology, metabolism, and hemodynamics. This article reviews the physiology, techniques, and clinical applications of diffusion-weighted and diffusion tensor imaging, MR spectroscopy, perfusion MR imaging, susceptibility-weighted imaging, and functional MR imaging in the setting of neuro-oncology...
February 2017: Neuroimaging Clinics of North America
https://www.readbyqxmd.com/read/27888345/robust-thalamic-nuclei-segmentation-method-based-on-local-diffusion-magnetic-resonance-properties
#13
Giovanni Battistella, Elena Najdenovska, Philippe Maeder, Naghmeh Ghazaleh, Alessandro Daducci, Jean-Philippe Thiran, Sébastien Jacquemont, Constantin Tuleasca, Marc Levivier, Meritxell Bach Cuadra, Eleonora Fornari
The thalamus is an essential relay station in the cortical-subcortical connections. It is characterized by a complex anatomical architecture composed of numerous small nuclei, which mediate the involvement of the thalamus in a wide range of neurological functions. We present a novel framework for segmenting the thalamic nuclei, which explores the orientation distribution functions (ODFs) from diffusion magnetic resonance images at 3 T. The differentiation of the complex intra-thalamic microstructure is improved by using the spherical harmonic (SH) representation of the ODFs, which provides full angular characterization of the diffusion process in each voxel...
November 25, 2016: Brain Structure & Function
https://www.readbyqxmd.com/read/27885285/emergence-of-aminoglycoside-resistance-due-to-arma-methylase-in-multi-drug-resistant-acinetobacter-baumannii-isolates-in-a-university-hospital-in-nepal
#14
S Shrestha, T Tada, B Shrestha, T Kirikae, H Ohara, B P Rijal, B M Pokhrel, J B Sherchand
BACKGROUND: The emergence of multidrug-resistant Acinetobacter baumannii associated with hospital-acquired infections has been increasingly reported worldwide. 16S rRNA methylase producing Gram-negative bacteria are highly resistant to all clinically important aminoglycosides. We analyzed A. baumannii clinical isolates resistant to aminoglycosides from hospitalized patients. The objective of this study was to investigate the emergence of armA in A.baumannii species associated with nosocomial infection in a university hospital in Nepal...
May 2016: Journal of Nepal Health Research Council
https://www.readbyqxmd.com/read/27880784/cdh1-missense-variant-c-1679c-g-p-t560r-completely-disrupts-normal-splicing-through-creation-of-a-novel-5-splice-site
#15
Zarina Yelskaya, Ruben Bacares, Erin Salo-Mullen, Joshua Somar, Deborah A Lehrich, Grace-Ann Fasaye, Daniel G Coit, Laura H Tang, Zsofia K Stadler, Liying Zhang
Disease-causing germline mutations in CDH1 cause Hereditary Diffuse Gastric Cancer (HDGC). For patients who meet the HDGC screening criteria, the identification and classification of the sequence variants found in CDH1 are critical for risk management of patients. In this report, we describe a germline CDH1 c.1679C>G (p.T560R) variant identified in a 50 year old man who was diagnosed with gastric cancer with a strong family history of gastric cancer (one living brother was diagnosed with gastric cancer at 63 and another brother died of gastric cancer at 45)...
2016: PloS One
https://www.readbyqxmd.com/read/27879030/age-related-decline-in-task-switching-is-linked-to-both-global-and-tract-specific-changes-in-white-matter-microstructure
#16
Todd A D Jolly, Patrick S Cooper, Jaime L Rennie, Christopher R Levi, Rhoshel Lenroot, Mark W Parsons, Patricia T Michie, Frini Karayanidis
Task-switching performance relies on a broadly distributed frontoparietal network and declines in older adults. In this study, they investigated whether this age-related decline in task switching performance was mediated by variability in global or regional white matter microstructural health. Seventy cognitively intact adults (43-87 years) completed a cued-trials task switching paradigm. Microstructural white matter measures were derived using diffusion tensor imaging (DTI) analyses on the diffusion-weighted imaging (DWI) sequence...
November 23, 2016: Human Brain Mapping
https://www.readbyqxmd.com/read/27878926/the-effects-of-dwi-infarct-lesion-volume-on-dwi-flair-mismatch-is-there-a-need-for-size-stratification
#17
Seyedmehdi Payabvash, Shayandokht Taleb, John C Benson, Jeffrey B Rykken, Mark C Oswood, Alexander M McKinney, Benjamin Hoffman
BACKGROUND: The lack of fluid-attenuated inversion-recovery (FLAIR) hyperintensity in areas of diffusion-weighted imaging (DWI) high signal, or DWI-FLAIR mismatch, is a potential imaging biomarker for timing of stroke onset. We aimed to determine the effects of DWI infarct lesion volume on DWI-FLAIR mismatch and its accuracy for identification of strokes within intravenous (IV) the thrombolytic therapy window. METHODS: Acute ischemic stroke patients with magnetic resonance imaging scan within 12 hours of witnessed stroke were included...
November 23, 2016: Journal of Neuroimaging: Official Journal of the American Society of Neuroimaging
https://www.readbyqxmd.com/read/27876066/in-vivo-cardiovascular-magnetic-resonance-of-2d-vessel-wall-diffusion-anisotropy-in-carotid-arteries
#18
Peter Opriessnig, Harald Mangge, Rudolf Stollberger, Hannes Deutschmann, Gernot Reishofer
BACKGROUND: Diffusion weighted (DW) cardiovascular magnetic resonance (CMR) has shown great potential to discriminate between healthy and diseased vessel tissue by evaluating the apparent diffusion coefficient (ADC) along the arterial axis. Recently, ex vivo studies on porcine arteries utilizing diffusion tensor imaging (DTI) revealed a circumferential fiber orientation rather than an organization in axial direction, suggesting dominant diffusion perpendicular to the slice direction. In the present study, we propose a method to access tangential and radial diffusion of carotids in vivo by utilizing a pulse sequence that enables high resolution DW imaging in combination with a two-dimensional (2D) diffusion gradient direction sampling scheme perpendicular to the longitudinal axis of the artery...
November 23, 2016: Journal of Cardiovascular Magnetic Resonance
https://www.readbyqxmd.com/read/27875687/complete-substitution-of-the-brazilian-endemic-clone-by-other-methicillin-resistant-staphylococcus-aureus-lineages-in-two-public-hospitals-in-rio-de-janeiro-brazil
#19
Raiane Cardoso Chamon, Sthefanie da Silva Ribeiro, Thaina Miranda da Costa, Simone Aranha Nouér, Katia Regina Netto Dos Santos
Staphylococcus aureus is an important cause of bloodstream infections (BSI). Therefore, the main purpose of this work was to characterize a collection of 139 S. aureus isolates from BSI in two public hospitals in relation to their antimicrobial susceptibility profile, SCCmec types, and clonal relationship. Methicillin resistance and resistance to other 12 agents were accessed by the disk diffusion test. Minimum inhibitory concentration (MIC) to mupirocin was also determined. The SCCmec types were accessed by multiplex PCR, and the clonal relationship was determined by pulsed field gel electrophoresis method and restriction modification system characterization...
November 19, 2016: Brazilian Journal of Infectious Diseases
https://www.readbyqxmd.com/read/27875092/morphological-variability-of-demodex-cati-in-a-feline-immunodeficiency-virus-positive-cat
#20
Elien R L Taffin, Stijn Casaert, Edwin Claerebout, Thomas J J Vandekerkhof, Sophie Vandenabeele
CASE DESCRIPTION A 17-year-old FIV-positive cat was evaluated because of weight loss during the preceding few months. The cat had a weight loss of 0.5 kg (1.1 lb) during the last month. Because of its FIV-positive status, the cat was confined indoors. CLINICAL FINDINGS A large nonpruritic area of alopecia with hyperpigmentation and comedones was present on the right lateral aspect of the neck. The chin had diffuse alopecia and comedones. Mild alopecia was present on the dorsal aspect of the muzzle. Trichography and microscopic examination of acetate tape imprint preparations and skin scrapings revealed a very morphologically heterogeneous population of Demodex mites...
December 1, 2016: Journal of the American Veterinary Medical Association
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