keyword
MENU ▼
Read by QxMD icon Read
search

Penumbra

keyword
https://www.readbyqxmd.com/read/28547529/toll-like-receptor-4-tlr4-and-triggering-receptor-expressed-on-myeloid-cells-2-trem-2-activation-balance-astrocyte-polarization-into-a-proinflammatory-phenotype
#1
Gerardo Rosciszewski, Vanesa Cadena, Veronica Murta, Jeronimo Lukin, Alejandro Villarreal, Thierry Roger, Alberto Javier Ramos
Astrocytes react to brain injury with a generic response known as reactive gliosis, which involves activation of multiple intracellular pathways including several that may be beneficial for neuronal survival. However, by unknown mechanisms, reactive astrocytes can polarize into a proinflammatory phenotype that induces neurodegeneration. In order to study reactive gliosis and astroglial polarization into a proinflammatory phenotype, we used cortical devascularization-induced brain ischemia in Wistar rats and primary astroglial cell cultures exposed to oxygen-glucose deprivation (OGD)...
May 25, 2017: Molecular Neurobiology
https://www.readbyqxmd.com/read/28545556/finer-leaf-resolution-and-steeper-beam-edges-using-a-virtual-isocentre-in-concurrence-to-ptv-shaped-collimators-in-standard-distance-a-planning-study
#2
Klaus Bratengeier, Barbara Herzog, Sonja Wegener, Kostyantyn Holubyev
PURPOSE: Investigation of a reduced source to target distance to improve organ at risk sparing during stereotactic irradiation (STX). METHODS: The authors present a planning study with perfectly target-volume adapted collimator compared with multi-leaf collimator (MLC) at reduced source to virtual isocentre distance (SVID) in contrast to normal source to isocentre distance (SID) for stereotactic applications. The role of MLC leaf width and 20-80% penumbra was examined concerning the healthy tissue sparing...
May 25, 2017: Radiation Oncology
https://www.readbyqxmd.com/read/28537507/electroacupuncture-alleviated-brain-damages-through-mir-191a-5p-targeting-neuronal-calcium-sensor-1-after-ischemic-stroke
#3
Heng Zhou, Ceng Yang, Fuhai Bai, Zhi Ma, Jingyi Wang, Feng Wang, Feng Li, Qiang Wang, Lize Xiong
Electroacupuncture (EA) administration before or after cerebral ischemia has been shown to afford protection against ischemic injury. However, the underlying mechanism of EA-mediated protection is still unclear. Functional microRNAs (miRNAs) are believed to play important roles in neuroprotection and synaptic plasticity during and after ischemia. In a previous study, we identified 20 miRNAs that are expressed in the penumbra and are significantly changed after EA treatment. Here, we used bioinformatics analysis to predict the biological functions and gene-networks of these miRNAs...
May 24, 2017: Rejuvenation Research
https://www.readbyqxmd.com/read/28531910/extracranial-carotid-disease-and-effect-of-intra-arterial-treatment-in-patients-with-proximal-anterior-circulation-stroke-in-mr-clean
#4
Olvert A Berkhemer, Jordi Borst, Manon Kappelhof, Albert J Yoo, Lucie A van den Berg, Puck S S Fransen, Debbie Beumer, Wouter J Schonewille, Paul J Nederkoorn, Marieke J H Wermer, Henk A Marquering, Hester F Lingsma, Yvo B W E M Roos, Robert J van Oostenbrugge, Diederik W J Dippel, Wim H van Zwam, Charles B L M Majoie, Bart J Emmer, Aad van der Lugt
Background: The presence of extracranial carotid disease (ECD) is associated with less favorable clinical outcomes a in patients with acute ischemic stroke caused by intracranial proximal occlusion. Acute intra-arterial treatment (IAT) in the setting of extracranial and intracranial lesions is considered challenging, and whether it yields improved outcomes remains uncertain. Objective: To examine whether the presence of ECD modified the effect of IAT for intracranial proximal anterior circulation occlusion...
May 23, 2017: Annals of Internal Medicine
https://www.readbyqxmd.com/read/28524074/neurotrauma-the-crosstalk-between-neurotrophins-and-inflammation-in-the-acutely-injured-brain
#5
REVIEW
Lindolfo da Silva Meirelles, Daniel Simon, Andrea Regner
Traumatic brain injury (TBI) is a major cause of morbidity and mortality among young individuals worldwide. Understanding the pathophysiology of neurotrauma is crucial for the development of more effective therapeutic strategies. After the trauma occurs, immediate neurologic damage is produced by the traumatic forces; this primary injury triggers a secondary wave of biochemical cascades together with metabolic and cellular changes, called secondary neural injury. In the scenario of the acutely injured brain, the ongoing secondary injury results in ischemia and edema culminating in an uncontrollable increase in intracranial pressure...
May 18, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28523299/three-dimensional-organ-scanning-reveals-brain-edema-reduction-in-a-rat-model-of-stroke-treated-with-an-aquaporin-4-inhibitor
#6
Elena Silvia Popescu, Ionica Pirici, Raluca Niculina Ciurea, Tudor Adrian Bălşeanu, Bogdan Cătălin, Claudiu Mărgăritescu, LaurenŢiu Mogoantă, Sorin Hostiuc, Daniel Pirici
Stroke is one of the most important cause of death and disability, especially when considering the increasing life expectancy worldwide, with ischemic stroke being much more common than hemorrhages. In the physiopathological chain of ischemic stroke, brain edema is one first element that if attended to might reduce tissue necrosis, penumbra, and increase functional recovery. Aquaporin 4 (AQP4) has been found to be the most important water channel in the brain, and its inhibition before inducing focal ischemia in an animal model of stroke proved to alleviate the pathology and improve clinical recovery...
2017: Romanian Journal of Morphology and Embryology, Revue Roumaine de Morphologie et Embryologie
https://www.readbyqxmd.com/read/28515593/role-of-penumbra-mechanical-thrombectomy-device-in-acute-dural-sinus-thrombosis
#7
Suraj Mammen, Shyamkumar Nidugala Keshava, Vinu Moses, Sanjith Aaron, Munawwar Ahmed, George K Chiramel, Sunithi E Mani, Mathew Alexander
BACKGROUND: In dural venous sinus thrombosis (DVST), the mortality ranges 5-30%. Deep venous system involvement and septic dural sinus thrombosis have a higher mortality rate. In acute occlusion, collateral flow may not be established, which may result in significant edema and mass effect. Endovascular interventions may be considered as a treatment option in appropriate high-risk patients with DVST. MATERIALS AND METHODS: Eight patients with magnetic resonance imaging (MRI)-confirmed dural sinus thrombosis, who did not respond to the conventional standard medical treatment, were subsequently treated with mechanical thrombectomy using the Penumbra System(®)...
January 2017: Indian Journal of Radiology & Imaging
https://www.readbyqxmd.com/read/28508117/single-center-experience-using-the-3max-reperfusion-catheter-for-the-treatment-of-acute-ischemic-stroke-with-distal-arterial-occlusions
#8
Kévin Premat, Bruno Bartolini, Flore Baronnet-Chauvet, Eimad Shotar, Vincent Degos, Paul Muresan, Federico Di Maria, Joseph Gabrieli, Charlotte Rosso, Silvia Pistocchi, Jacques Chiras, Nader Sourour, Sonia Alamowitch, Yves Samson, Frédéric Clarençon
PURPOSE: Most recent guidelines recommend the use of stent retriever devices in endovascular treatment of acute ischemic stroke with large vessel occlusion (LVO). Recently published data reported convincing results with thromboaspiration devices such as the Penumbra System (Penumbra, Alameda, CA, USA) combined with supple reperfusion catheters by using the ADAPT (A Direct Aspiration First-Pass Thrombectomy) technique. The aim of this study was to report our initial experience with the 3MAX (3...
May 15, 2017: Clinical Neuroradiology
https://www.readbyqxmd.com/read/28506162/brodie-s-abscess-of-the-radius-in-a-child
#9
N Takeuchi, Y Matsumoto, T Okada, M Hanada, H Bekki, Y Iwamoto
We herein report an unusual case of Brodie's abscess of the radius in a child. A 13-year-old boy presented with pain on his right distal forearm. A plain radiograph showed an 8 cm translucent lesion in the distal radius. MRI showed a penumbra sign on the T1-weighted image, hyperintensity on T2-weighted images, and ring enhancement on the contrast-enhanced T1 image. (18)F-FDG PET/CT images showed an uptake at the margin of the radius. Curettage and iliac cancellous bone grafting were undertaken for Brodie's abscess...
June 2017: Journal of Hand Surgery Asian-Pacific Volume
https://www.readbyqxmd.com/read/28506087/differential-variations-of-autophagy-and-apoptosis-in-permanent-focal-cerebral-ischaemia-rat-model
#10
Pengyue Zhang, Liqiang Yang, Hongyun He, Yihao Deng
OBJECTIVE: Autophagy and apoptosis coexist in stroke, but the relationship between effects and complex is poorly understood. Herein, we investigated dynamic changes of autophagy and apoptosis at the penumbra in permanent cerebral ischaemia. METHODS: Sprague-Dawley rat models were prepared by middle cerebral artery occlusion. The autophagy and apoptosis were evaluated by Western blotting and immunofluorescence with LC3-II and cleaved caspase-3, respectively. The neurological deficit score and infarct volume were assessed...
May 16, 2017: Brain Injury: [BI]
https://www.readbyqxmd.com/read/28503134/aquaporin-4-mediated-glutamate-induced-astrocyte-swelling-is-partially-mediated-through-metabotropic-glutamate-receptor-5-activation
#11
Zhongfang Shi, Wei Zhang, Yang Lu, Yi Lu, Lixin Xu, Qing Fang, Min Wu, Mei Jia, Yujiao Wang, Liping Dong, Xu Yan, Shaohua Yang, Fang Yuan
Astrocytes are one of the most abundant cell types in the mammalian central nervous system (CNS), and astrocyte swelling is the primary event associated with brain edema. Glutamate, the principal excitatory amino acid neurotransmitter in the CNS, is released at high levels after brain injury including cerebral ischemia. This leads to astrocyte swelling, which we previously demonstrated is related to metabotropic glutamate receptor (mGluR) activation. Aquaporin 4 (AQP4), the predominant water channel in the brain, is expressed in astrocyte endfeet and plays an important role in brain edema following ischemia...
2017: Frontiers in Cellular Neuroscience
https://www.readbyqxmd.com/read/28498612/design-of-a-modulated-orthovoltage-stereotactic-radiosurgery-system
#12
Jessica M Fagerstrom, Edward T Bender, Michael J Lawless, Wesley S Culberson
PURPOSE: To achieve stereotactic radiosurgery (SRS) dose distributions with sharp gradients using orthovoltage energy fluence modulation with inverse planning optimization techniques. METHODS: A pencil beam model was used to calculate dose distributions from an orthovoltage unit at 250 kVp. Kernels for the model were derived using Monte Carlo methods. A Genetic Algorithm search heuristic was used to optimize the spatial distribution of added tungsten filtration to achieve dose distributions with sharp dose gradients...
May 12, 2017: Medical Physics
https://www.readbyqxmd.com/read/28494095/comparison-of-192-ir-169-yb-and-60-co-high-dose-rate-brachytherapy-sources-for-skin-cancer-treatment
#13
Habib Safigholi, Ali S Meigooni, William Y Song
PURPOSE: To evaluate the possibility of utilizing the high-dose rate (HDR) (169) Yb and (60) Co sources, in addition to (192) Ir, for the treatment of skin malignancies with conical applicators. METHODS: Monte Carlo (MC) simulations were used to benchmark the dosimetric parameters of single (169) Yb (4140), (60) Co (Co0.A86), and (192) Ir (mHDR-V2) brachytherapy sources in a water phantom and compared their results against published data. A standard conical tungsten alloy Leipzig-style applicator (Stand...
May 11, 2017: Medical Physics
https://www.readbyqxmd.com/read/28487326/xbp1-x-box-binding-protein-1-dependent-o-glcnacylation-is-neuroprotective-in-ischemic-stroke-in-young-mice-and-its-impairment-in-aged-mice-is-rescued-by-thiamet-g
#14
Meng Jiang, Shu Yu, Zhui Yu, Huaxin Sheng, Ying Li, Shuai Liu, David S Warner, Wulf Paschen, Wei Yang
BACKGROUND AND PURPOSE: Impaired protein homeostasis induced by endoplasmic reticulum dysfunction is a key feature of a variety of age-related brain diseases including stroke. To restore endoplasmic reticulum function impaired by stress, the unfolded protein response is activated. A key unfolded protein response prosurvival pathway is controlled by the endoplasmic reticulum stress sensor (inositol-requiring enzyme-1), XBP1 (downstream X-box-binding protein-1), and O-GlcNAc (O-linked β-N-acetylglucosamine) modification of proteins (O-GlcNAcylation)...
May 9, 2017: Stroke; a Journal of Cerebral Circulation
https://www.readbyqxmd.com/read/28486941/neuroprotective-effect-of-salvianolate-lyophilized-injection-against-cerebral-ischemia-in-type-1-diabetic-rats
#15
Fujiang Wang, Qiansong He, Jinxin Wang, Qing Yuan, Hong Guo, Lijuan Chai, Shaoxia Wang, Limin Hu, Yue Zhang
BACKGROUND: Salvianolate lyophilized injection (SLI) has been clinically used in China for the treatment of acutely cerebral infarction. Clinical and experimental studies have shown that Diabetes mellitus (DM) not only increases the risk of ischemic stroke recurrence but also leads to poor outcomes and increases fatality rates after stroke. Our previous study has proved that SLI can reduce the infarct volume after stroke in type 1 diabetic rats. The aim of the study is to explore the mechanism of SLI on stroke outcome in type 1 diabetic (T1DM) rats...
May 10, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28486789/ct-perfusion-to-predict-response-to-recanalization-in-ischemic-stroke
#16
Maarten G Lansberg, Soren Christensen, Stephanie Kemp, Michael Mlynash, Nishant Mishra, Christian Federau, Jenny P Tsai, Sun Kim, Raul G Nogueria, Tudor Jovin, Thomas G Devlin, Naveed Akhtar, Dileep R Yavagal, Diogo Haussen, Seena Dehkharghani, Roland Bammer, Matus Straka, Greg Zaharchuk, Michael P Marks, Gregory W Albers
OBJECTIVE: To assess the utility of CT perfusion for selection of patients for endovascular therapy up to 18 hours after symptom onset. METHODS: We conducted a multicenter cohort study of consecutive acute stroke patients scheduled to undergo endovascular therapy within 90 min after a baseline CTP. Patients were classified as 'target mismatch' if they had a small ischemic core and a large penumbra on their baseline CT perfusion. Reperfusion was defined as >50% reduction in critical hypoperfusion between the baseline CT perfusion and the 36-hour follow-up MRI...
May 9, 2017: Annals of Neurology
https://www.readbyqxmd.com/read/28485194/chemical-exchange-sensitive-spin-lock-mri-of-glucose-analog-3-o-methyl-d-glucose-in-normal-and-ischemic-brain
#17
Tao Jin, Hunter Mehrens, Ping Wang, Seong-Gi Kim
Glucose transport is important for understanding brain glucose metabolism. We studied glucose transport with a presumably non-toxic and non-metabolizable glucose analog, 3-O-methyl-d-glucose, using a chemical exchange-sensitive spin-lock MRI technique at 9.4 Tesla. 3-O-methyl-d-glucose showed comparable chemical exchange properties with d-glucose and 2-deoxy-d-glucose in phantoms, and higher and lower chemical exchange-sensitive spin-lock sensitivity than Glc and 2-deoxy-d-glucose in in vivo experiments, respectively...
January 1, 2017: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/28481639/ct-measure-of-lung-at-risk-and-lung-function-decline-in-chronic-obstructive-pulmonary-disease
#18
Surya P Bhatt, Sandeep Bodduluri, Eric A Hoffman, John D Newell, Jessica C Sieren, Mark T Dransfield, Joseph M Reinhardt
RATIONALE: The rate of decline of lung function is greater than age-related change in a substantial proportion of patients with COPD, even after smoking cessation. Regions of the lung adjacent to emphysematous areas are subject to abnormal stretch during respiration, and this biomechanical stress likely influences emphysema initiation and progression. OBJECTIVE: To assess whether quantifying this penumbra of lung-at-risk would predict FEV1 decline. METHODS: We analyzed paired inspiratory-expiratory computerized tomography (CT) images at baseline of 680 subjects participating in a large multicenter study (COPDGene) over approximately 5 years...
May 8, 2017: American Journal of Respiratory and Critical Care Medicine
https://www.readbyqxmd.com/read/28479590/cerebral-granulomatous-inflammation-secondary-to-hydrophilic-polymer-embolization-following-thrombectomy
#19
Craig Meiers, Yoftahe Abebe, Neville M Alberto, John Riedinger, Dane A Breker, Michael Manchak, Alexander Drofa, Corey Teigen
BACKGROUND Given the recent completion of multiple trials demonstrating the benefit of endovascular mechanical thrombectomy for select patients with proximal large artery occlusive ischemic strokes, there has been a large increase in the performance of these procedures. In the context of increased thrombectomy performance, there have also been increased reports of rare occurrences of granulomatous inflammatory response to the hydrophilic polymer which coat many of these interventional devices. CASE REPORT A 59-year-old female presented with a complete occlusion of her right proximal middle cerebral artery (MCA) and imaging showed a large area of penumbra...
May 8, 2017: American Journal of Case Reports
https://www.readbyqxmd.com/read/28479465/safety-of-early-carotid-endarterectomy-after-intravenous-thrombolysis-in-acute-ischemic-stroke
#20
Igor Gunka, Dagmar Krajickova, Michal Lesko, Ondrej Renc, Jan Raupach, Stanislav Jiska, Miroslav Lojik, Vendelin Chovanec, Radovan Maly
BACKGROUND: The timing of carotid endarterectomy (CEA) after intravenous thrombolysis (IVT) is still a controversial issue. The aim of this study was to assess the safety of early carotid interventions in patients treated with thrombolysis for acute ischemic stroke. MATERIAL AND METHODS: A retrospective analysis was performed using prospectively collected data from consecutive patients who underwent CEA for symptomatic internal carotid artery stenosis within 14 days after the index neurological event during the period from January 2013 to July 2016...
May 4, 2017: Annals of Vascular Surgery
keyword
keyword
758
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"