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https://www.readbyqxmd.com/read/27915429/high-risk-pml-patients-switching-from-natalizumab-to-alemtuzumab-an-observational-study
#1
Simona Malucchi, Marco Capobianco, Marianna Lo Re, Maria Malentacchi, Alessia di Sapio, Manuela Matta, Francesca Sperli, Antonio Bertolotto
INTRODUCTION: The choice of therapy in patients withdrawing from natalizumab treatment is still an open question and neurologists need strategies to manage this group of patients. The aim of this study is to evaluate if alemtuzumab is able to control the disease when used in patient who have stopped natalizumab. METHODS: 16 patients stopped natalizumab treatment after a median number of 20 infusions (range 12-114); all the patients were responders to natalizumab (neither clinical nor radiological activity during natalizumab therapy) and the reason for stopping was the risk of PML for all of them...
December 3, 2016: Neurology and Therapy
https://www.readbyqxmd.com/read/27914180/burned-out-testis-tumors-in-asymptomatic-infertile-men-multiparametric-sonography-and-mri-findings
#2
Laurence Rocher, Ludivine Glas, Marie France Bellin, Sophie Ferlicot, Vincent Izard, Gerard Benoit, Laurence Albiges, Karim Fizazi, Jean-Michel Correas
Multiparametric testicular ultrasound and magnetic resonance imaging (MRI) findings were analyzed in a series of 10 infertile asymptomatic men presenting with pathologically confirmed burned-out testicular tumors. Color/power Doppler ultrasound (CDUS), shear wave elastography (SWE), contrast-enhanced ultrasonography (CEUS), and MRI were performed on 10, 5, 6, and 7 patients, respectively. All lesions appeared as a hypoechoic and hypovascular nodular area at CDUS, SWE, CEUS CDUS, and CEUS (if performed). Shear wave elastography showed a stiffer nodular area compared with the surrounding/contralateral tissues (13 versus 2 kPa); MRI revealed a well-delineated nodular area in hypointense signal on T2, a high apparent diffusion coefficient value, and a lack of enhancement...
December 3, 2016: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
https://www.readbyqxmd.com/read/27914172/cryotherapy-of-renal-lesions-enhancement-on-contrast-enhanced-sonography-on-postoperative-day-1-does-not-imply-viable-tissue-persistence
#3
Michele Bertolotto, Salvatore Siracusano, Calogero Cicero, Mariano Iannelli, Tommaso Silvestri, Antonio Celia, Alessandro Guarise, Fulvio Stacul
OBJECTIVES: To investigate whether persistent enhancement detected on contrast-enhanced sonography at postoperative day 1 (early contrast-enhanced sonography) after cryoablation of renal tumors implies the presence of residual viable tumor tissue, defined as residual enhancing tissue on reference imaging (computed tomography or magnetic resonance imaging) performed 6 months after the procedure. METHODS: Seventy-four patients with percutaneous cryoablation of renal tumors had early contrast-enhanced sonography from November 2011 to August 2015...
December 3, 2016: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
https://www.readbyqxmd.com/read/27913960/neuroimaging-abnormalities-in-clade-c-hiv-are-independent-of-tat-genetic-diversity
#4
Robert H Paul, Sarah Phillips, Jacqueline Hoare, David H Laidlaw, Ryan Cabeen, Gayla R Olbricht, Yuqing Su, Dan J Stein, Susan Engelbrecht, Soraya Seedat, Lauren E Salminen, Laurie M Baker, Jodi Heaps, John Joska
Controversy remains regarding the neurotoxicity of clade C human immunodeficiency virus (HIV-C). When examined in preclinical studies, a cysteine to serine substitution in the C31 dicysteine motif of the HIV-C Tat protein (C31S) results in less severe brain injury compared to other viral clades. By contrast, patient cohort studies identify significant neuropsychological impairment among HIV-C individuals independent of Tat variability. The present study clarified this discrepancy by examining neuroimaging markers of brain integrity among HIV-C individuals with and without the Tat substitution...
December 2, 2016: Journal of Neurovirology
https://www.readbyqxmd.com/read/27913827/intra-lesional-spatial-correlation-of-static-and-dynamic-fet-pet-parameters-with-mri-based-cerebral-blood-volume-in-patients-with-untreated-glioma
#5
Jens Göttler, Mathias Lukas, Anne Kluge, Stephan Kaczmarz, Jens Gempt, Florian Ringel, Mona Mustafa, Bernhard Meyer, Claus Zimmer, Markus Schwaiger, Stefan Förster, Christine Preibisch, Thomas Pyka
PURPOSE: (18)F-fluorethyltyrosine-(FET)-PET and MRI-based relative cerebral blood volume (rCBV) have both been used to characterize gliomas. Recently, inter-individual correlations between peak static FET-uptake and rCBV have been reported. Herein, we assess the local intra-lesional relation between FET-PET parameters and rCBV. METHODS: Thirty untreated glioma patients (27 high-grade) underwent simultaneous PET/MRI on a 3 T hybrid scanner obtaining structural and dynamic susceptibility contrast sequences...
December 2, 2016: European Journal of Nuclear Medicine and Molecular Imaging
https://www.readbyqxmd.com/read/27913433/medial-temporal-lobe-contributions-to-episodic-future-thinking-scene-construction-or-future-projection
#6
D J Palombo, S M Hayes, K M Peterson, M M Keane, M Verfaellie
Previous research has shown that the medial temporal lobes (MTL) are more strongly engaged when individuals think about the future than about the present, leading to the suggestion that future projection drives MTL engagement. However, future thinking tasks often involve scene processing, leaving open the alternative possibility that scene-construction demands, rather than future projection, are responsible for the MTL differences observed in prior work. This study explores this alternative account. Using functional magnetic resonance imaging, we directly contrasted MTL activity in 1) high scene-construction and low scene-construction imagination conditions matched in future thinking demands and 2) future-oriented and present-oriented imagination conditions matched in scene-construction demands...
December 1, 2016: Cerebral Cortex
https://www.readbyqxmd.com/read/27911291/a-metal-free-method-for-producing-mri-contrast-at-amyloid-%C3%AE
#7
Silvia Hilt, Tang Tang, Jeffrey H Walton, Madhu Budamagunta, Izumi Maezawa, Tamás Kálai, Kálmán Hideg, Vikrant Singh, Heike Wulff, Qizhi Gong, Lee-Way Jin, Angelique Louie, John C Voss
Alzheimer's disease (AD) is characterized by depositions of the amyloid-β (Aβ) peptide in the brain. The disease process develops over decades, with substantial neurological loss occurring before a clinical diagnosis of dementia can be rendered. It is therefore imperative to develop methods that permit early detection and monitoring of disease progression. In addition, the multifactorial pathogenesis of AD has identified several potential avenues for AD intervention. Thus, evaluation of therapeutic candidates over lengthy trial periods also demands a practical, noninvasive method for measuring Aβ in the brain...
November 26, 2016: Journal of Alzheimer's Disease: JAD
https://www.readbyqxmd.com/read/27910951/molecular-imaging-with-engineered-physiology
#8
Mitul Desai, Adrian L Slusarczyk, Ashley Chapin, Mariya Barch, Alan Jasanoff
In vivo imaging techniques are powerful tools for evaluating biological systems. Relating image signals to precise molecular phenomena can be challenging, however, due to limitations of the existing optical, magnetic and radioactive imaging probe mechanisms. Here we demonstrate a concept for molecular imaging which bypasses the need for conventional imaging agents by perturbing the endogenous multimodal contrast provided by the vasculature. Variants of the calcitonin gene-related peptide artificially activate vasodilation pathways in rat brain and induce contrast changes that are readily measured by optical and magnetic resonance imaging...
December 2, 2016: Nature Communications
https://www.readbyqxmd.com/read/27910866/biomechanical-analysis-of-normal-brain-development-during-the-first-year-of-life-using-finite-strain-theory
#9
Jeong Chul Kim, Li Wang, Dinggang Shen, Weili Lin
The first year of life is the most critical time period for structural and functional development of the human brain. Combining longitudinal MR imaging and finite strain theory, this study aimed to provide new insights into normal brain development through a biomechanical framework. Thirty-three normal infants were longitudinally imaged using MRI from 2 weeks to 1 year of age. Voxel-wise Jacobian determinant was estimated to elucidate volumetric changes while Lagrange strains (both normal and shear strains) were measured to reveal directional growth information every 3 months during the first year of life...
December 2, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27910719/artifacts-in-multimodal-imaging-of-titanium-zirconium-and-binary-titanium-zirconium-alloy-dental-implants-an-in-vitro-study
#10
Ralf Smeets, Maximilian Schöllchen, Tobias Gauer, Gahzal Aarabi, Alexandre T Assaf, Carsten Rendenbach, Benedicta Beck-Broichsitter, Jan Semmusch, Jan Sedlacik, Max Heiland, Jens Fiehler, Susanne Siemonsen
OBJECTIVES: To analyze and evaluate imaging artifacts induced by zirconium, titanium and titanium-zirconium alloy dental implants. METHODS: Zirconium, titanium and titanium-zirconium alloy implants were embedded in gelatin and MRI, CT and CBCT were performed. Standard-protocols were used for each modality. For MRI, line-distance-profiles were plotted to quantify the accuracy of size-determination. For CT and CBCT, six shells surrounding the implant were defined every 0...
December 2, 2016: Dento Maxillo Facial Radiology
https://www.readbyqxmd.com/read/27910222/cyclic-vomiting-syndrome-is-characterized-by-altered-functional-brain-connectivity-of-the-insular-cortex-a-cross-comparison-with-migraine-and-healthy-adults
#11
D-M Ellingsen, R G Garcia, J Lee, R L Lin, J Kim, A H Thurler, S Castel, L Dimisko, B R Rosen, N Hadjikhani, B Kuo, V Napadow
Cyclic Vomiting Syndrome (CVS) has been linked to episodic migraine, yet little is known about the precise brain-based mechanisms underpinning CVS, and whether these associated conditions share similar pathophysiology. We investigated the functional integrity of salience (SLN) and sensorimotor (SMN) intrinsic connectivity networks in CVS, migraine and healthy controls using brain functional Magnetic Resonance Imaging. CVS, relative to both migraine and controls, showed increased SLN connectivity to middle/posterior insula, a key brain region for nausea and viscerosensory processing...
December 1, 2016: Neurogastroenterology and Motility: the Official Journal of the European Gastrointestinal Motility Society
https://www.readbyqxmd.com/read/27909413/sex-effects-on-smoking-cue-perception-in-non-smokers-smokers-and-ex-smokers-a-pilot-study
#12
Davide Zanchi, Arthur Brody, Stefan Borgwardt, Sven Haller
INTRODUCTION: Recent neuroimaging research suggests sex-related brain differences in smoking addiction. In the present pilot study, we assessed gender-related differences in brain activation in response to cigarette-related video cues, investigating non-smokers, smokers, and ex-smokers. METHODS: First, we compared 29 females (28.6 ± 5.3) vs. 23 males (31.5 ± 6.4), regardless of current smoking status to assess global gender-related effects. Second, we performed a post hoc analysis of non-smokers (9 females and 8 males), smokers (10 females and 8 males), and ex-smokers (10 females and 7 males)...
2016: Frontiers in Psychiatry
https://www.readbyqxmd.com/read/27909401/implicit-learning-in-transient-global-amnesia-and-the-role-of-stress
#13
Frauke Nees, Martin Griebe, Anne Ebert, Michaela Ruttorf, Benjamin Gerber, Oliver T Wolf, Lothar R Schad, Achim Gass, Kristina Szabo
Transient global amnesia (TGA) is a disorder with reversible anterograde disturbance of explicit memory, frequently preceded by an emotionally or physically stressful event. By using magnetic resonance imaging (MRI) following an episode of TGA, small hippocampal lesions have been observed. Hence it has been postulated that the disorder is caused by the stress-related transient inhibition of memory formation in the hippocampus. In experimental studies, stress has been shown to affect both explicit and implicit learning-the latter defined as learning and memory processes that lack conscious awareness of the information acquired...
2016: Frontiers in Behavioral Neuroscience
https://www.readbyqxmd.com/read/27909118/the-relative-contribution-of-the-medial-and-lateral-femoral-circumflex-arteries-to-the-vascularity-of-the-head-and-neck-of-the-femur-a-quantitative-mri-based-assessment
#14
D C Dewar, L E Lazaro, C E Klinger, P K Sculco, J P Dyke, A Y Ni, D L Helfet, D G Lorich
AIMS: We aimed to quantify the relative contributions of the medial femoral circumflex artery (MFCA) and lateral femoral circumflex artery (LFCA) to the arterial supply of the head and neck of the femur. MATERIALS AND METHODS: We acquired ten cadaveric pelvises. In each of these, one hip was randomly assigned as experimental and the other as a matched control. The MFCA and LFCA were cannulated bilaterally. The hips were designated LFCA-experimental or MFCA-experimental and underwent quantitative MRI using a 2 mm slice thickness before and after injection of MRI-contrast diluted 3:1 with saline (15 ml Gd-DTPA) into either the LFCA or MFCA...
December 2016: Bone & Joint Journal
https://www.readbyqxmd.com/read/27908724/cell-surface-engineering-to-embed-targeting-ligands-or-tracking-agents-on-the-cell-membrane
#15
Kwang Suk Lim, Daniel Y Lee, Gabriel M Valencia, Young-Wook Won, David A Bull
The key challenge to improve the efficacy of cell therapy is how to efficiently modify cells with a specific molecule or compound that can guide the cells to the target tissue. To address this, we have developed a cell surface engineering technology to non-invasively modify the cell surface. This technology can embed a wide variety of bioactive molecules on any cell surface and allow for the targeting of a wide range of tissues in a variety of disease states. Using our cell surface engineering technology, mesenchymal stem cells (MSC)s were modified with: 1) a homing peptide or a recombinant protein to facilitate the migration of the cells toward a specific molecular target; or 2) magnetic resonance imaging (MRI) contrast agents to allow for in vivo tracking of the cells...
November 28, 2016: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/27908189/thermoacoustic-imaging-of-rabbit-knee-joints
#16
Zihui Chi, Yuan Zhao, Lin Huang, Zhu Zheng, Huabei Jiang
PURPOSE: Knee joint is one of the largest and most complex joints of the body. Knee joint diseases are common, and current clinical imaging technologies such as x-ray computed tomography, magnetic resonance imaging, and ultrasound imaging have limitations in the diagnosis of knee joint diseases. Emerging imaging technologies such as diffuse optical tomography and photoacoustic imaging (PAI) have been applied to the detection of osteoarthritis (OA). However, they are limited to small joints such as the finger and difficult to be used for large joints such as the knee...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27908163/learning-based-3t-brain-mri-segmentation-with-guidance-from-7t-mri-labeling
#17
Minghui Deng, Renping Yu, Li Wang, Feng Shi, Pew-Thian Yap, Dinggang Shen
PURPOSE: Segmentation of brain magnetic resonance (MR) images into white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF) is crucial for brain structural measurement and disease diagnosis. Learning-based segmentation methods depend largely on the availability of good training ground truth. However, the commonly used 3T MR images are of insufficient image quality and often exhibit poor intensity contrast between WM, GM, and CSF. Therefore, they are not ideal for providing good ground truth label data for training learning-based methods...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27907931/-koronararterienanomalien-diagnostik-und-klassifikation-auf-basis-der-ct-und-mrt-des-herzens-von-alcapa-bis-terminationsanomaliecoronary-artery-anomalies-diagnosis-and-classification-based-on-cardiac-ct-and-mri-cmr-from-alcapa-to-anomalies-of-termination
#18
Philipp Heermann, Walter Heindel, Christoph Schülke
Background Coronary artery anomalies encompass a clinically and anatomically variable spectrum including physiological variants and pathophysiologically relevant anomalies. The majority of the variants has no hemodynamic relevance and is often detected accidentally. The recognition of the rare and relevant anomalies that cause either relevant shunt volumes leading to myocardial ischemia or ventricular tachyarrhythmias with the risk of sudden cardiac death is of major importance. Methods This review is based on a literature search in PubMed conducted using the key words "coronary artery" and/or "anomaly" and/or "anomalous origin" and/or "myocardial bridging" and/or "coronary artery fistula" and/or "Bland-White-Garland" and/or "ALCAPA"...
December 1, 2016: RöFo: Fortschritte Auf Dem Gebiete der Röntgenstrahlen und der Nuklearmedizin
https://www.readbyqxmd.com/read/27906396/gadolinium-oxysulfide-coated-gold-nanorods-with-improved-stability-and-dual-modal-magnetic-resonance-photoacoustic-imaging-contrast-enhancement-for-cancer-theranostics
#19
Tao Guo, Yan Lin, Zhi Li, Shan Chen, Guoming Huang, Huirong Lin, Jun Wang, Gang Liu, Huang-Hao Yang
Gold nanorods (GNRs) are emerging as a promising nanoplatform for cancer theranostics because of their unique optical properties. However, they still suffer from many limitations, such as high cytotoxicity, low thermodynamic and biological stability, and a tedious process for integrating other imaging modalities, for further practical biomedical applications. In this work, a strategy by one-step coating of Gd2O2S around GNRs is reported to address these limitations of GNRs. After the coating of the Gd2O2S shell, the as-fabricated Gd2O2S coated GNRs (GNRs@Gd2O2S) show enhanced biocompatibility and photostability, and tunable localized surface plasmon resonance...
December 1, 2016: Nanoscale
https://www.readbyqxmd.com/read/27906054/is-radical-surgery-of-an-inverted-papilloma-of-the-maxillary-sinus-obsolete-a-case-report
#20
Vedat Yildirim, Niels Christian Pausch, Dirk Halama, Heinz-Theo Lübbers, Ayhan Yildirim
BACKGROUND: Sinonasal inverted papilloma is a locally aggressive tumor arising from the Schneiderian membrane which lines the nasal cavity and paranasal sinuses. Aggressive surgical approaches, such as lateral rhinotomy, were used until recently for complete removal of the inverted papilloma. Currently, endoscopic resection is the gold standard in the treatment of inverted papilloma. However, there are situations that justify an open approach. For example there are studies that report a higher postoperative recurrence rate after endonasal endoscopic resection, particularly in the treatment of recurrent diseases...
December 1, 2016: Journal of Medical Case Reports
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