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https://www.readbyqxmd.com/read/28214521/neuroprotective-effect-of-salvianolic-acid-b-against-cerebral-ischemic-injury-in-rats-via-the-cd40-nf-%C3%AE%C2%BAb-pathway-associated-with-suppression-of-platelets-activation-and-neuroinflammation
#1
Shixin Xu, Aiqin Zhong, Huining Ma, Dan Li, Yue Hu, Yingzhi Xu, Junping Zhang
Neuroinflammation plays a critical role in the pathogenesis of ischemia/reperfusion (I/R) injury. Activated platelets are increasingly regarded as initiators and/or amplifiers of inflammatory processes in cerebral I/R injury. Salvianolic acid B (SAB) is the most abundant bioactive compound of Salviae miltiorrhizae, a well-known Chinese herb used to promote blood circulation and eliminating blood stasis. S. miltiorrhizae has been used clinically in Asia for the treatment of ischemic cerebrovascular diseases...
February 15, 2017: Brain Research
https://www.readbyqxmd.com/read/28207602/spreading-depolarization-monitoring-in-neurocritical-care-of-acute-brain-injury
#2
Jed A Hartings
PURPOSE OF REVIEW: Spreading depolarizations are unique in being discrete pathologic entities that are well characterized experimentally and also occur commonly in patients with substantial acute brain injury. Here, we review essential concepts in depolarization monitoring, highlighting its clinical significance, interpretation, and future potential. RECENT FINDINGS: Cortical lesion development in diverse animal models is mediated by tissue waves of mass spreading depolarization that cause the toxic loss of ion homeostasis and limit energy substrate supply through associated vasoconstriction...
February 14, 2017: Current Opinion in Critical Care
https://www.readbyqxmd.com/read/28202414/lncrna-tug1-sponges-microrna-9-to-promote-neurons-apoptosis-by-up-regulated-bcl2l11-under-ischemia
#3
Shengcai Chen, Mengdie Wang, Hang Yang, Ling Mao, Quanwei He, Huijuan Jin, Zi-Ming Ye, Xue-Ying Luo, Yuan-Peng Xia, Bo Hu
Emerging studies have illustrated that LncRNAs TUG1 play critical roles in multiple biologic processes. However, the LncRNA TUG1 expression and function in ischemic stroke have not been reported yet. In this study, we found that LncRNA TUG1 expression was significantly up-regulated in brain ischemic penumbra from rat middle carotid artery occlusion (MCAO) model, while similar results were also observed in cultured neurons under oxygen-glucose deprivation (OGD) insult. Knockdown of TUG1 decreased the ratio of apoptotic cells and promoted cells survival in vitro, which may be regulated by the elevated miRNA-9 expression and decreased Bcl2l11 protein...
February 12, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/28192195/puerarin-provides-a-neuroprotection-against-transient-cerebral-ischemia-by-attenuating-autophagy-at-the-ischemic-penumbra-in-neurons-but-not-in-astrocytes
#4
He Hongyun, Guo Tao, Zhang Pengyue, Yang Liqiang, Deng Yihao
Puerarin is an isoflavone derived from the Chinese medical herb of Radix puerariae (kudzu root), and has been widely used in the treatment for ischemic stroke in China. However, its underlying pharmacological mechanisms are still not understood. This study was to investigate the efficacy of puerarin on autophagy in the ischemic penumbra after cerebral stroke. A model of cerebral stroke in Sprague-Dawley rats was prepared by middle cerebral artery occlusion (MCAO); rats were then randomly divided into 5 groups: MCAO+Pue group (rats were treated with puerarin), MCAO+Pue+Tat-Beclin-1 group (rats were administrated with both puerarin and autophagy inducer Tat-Beclin-1), MCAO+Tat-Beclin-1 group (rats were treated with Tat-Beclin-1), MCAO+saline group (rats were administrated with the same volume of physiological saline), and sham surgery group...
February 10, 2017: Neuroscience Letters
https://www.readbyqxmd.com/read/28188261/role-of-genetic-variation-in-collateral-circulation-in-the-evolution-of-acute-stroke-a-multimodal-magnetic-resonance-imaging-study
#5
Yu-Chieh Jill Kao, Esteban A Oyarzabal, Hua Zhang, James E Faber, Yen-Yu Ian Shih
BACKGROUND AND PURPOSE: No studies have determined the effect of differences in pial collateral extent (number and diameter), independent of differences in environmental factors and unknown genetic factors, on severity of stroke. We examined ischemic tissue evolution during acute stroke, as measured by magnetic resonance imaging and histology, by comparing 2 congenic mouse strains with otherwise identical genetic backgrounds but with different alleles of the Determinant of collateral extent-1 (Dce1) genetic locus...
February 10, 2017: Stroke; a Journal of Cerebral Circulation
https://www.readbyqxmd.com/read/28178170/use-of-susceptibility-weighted-imaging-in-assessing-ischemic-penumbra-a-case-report
#6
Xiujuan Wu, Song Luo, Ying Wang, Yang Chen, Jun Liu, Jing Bai, Jiachun Feng, Hongliang Zhang
RATIONALE: The ischemic penumbra assessment is essential for the subsequent therapy and prediction of evolution in patients with acute ischemic infraction. Although controversial as a perfect equivalence to penumbra, perfusion-weighted imaging (PWI)-diffusion-weighted imaging (DWI) mismatch may predict the response to thrombolysis. Due to the reliance of PWI on contrast agents, noninvasive alternatives remain an unmet need. PATIENT CONCERNS: We reported a 65-year-old man complained of paroxysmal hemiplegia of his right limbs and anepia for 2 days, whereas the symptoms lasted for about 12 hours when he admitted to the hospital...
February 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28154103/acute-ischemic-stroke-therapy-overview
#7
Luciana Catanese, Joseph Tarsia, Marc Fisher
The treatment of acute ischemic stroke has undergone dramatic changes recently subsequent to the demonstrated efficacy of intra-arterial (IA) device-based therapy in multiple trials. The selection of patients for both intravenous and IA therapy is based on timely imaging with either computed tomography or magnetic resonance imaging, and if IA therapy is considered noninvasive, angiography with one of these modalities is necessary to document a large-vessel occlusion amenable for intervention. More advanced computed tomography and magnetic resonance imaging studies are available that can be used to identify a small ischemic core and ischemic penumbra, and this information will contribute increasingly in treatment decisions as the therapeutic time window is lengthened...
February 3, 2017: Circulation Research
https://www.readbyqxmd.com/read/28152195/a-2d-silicon-detector-array-for-quality-assurance-in-small-field-dosimetry-duo
#8
Khalsa Al Shukaili, Marco Petasecca, Matthew Newall, Anthony Espinoza, Vladimir L Perevertaylo, Stéphanie Corde, Michael Lerch, Anatoly B Rosenfeld
PURPOSE: Nowadays, there are many different applications that use small fields in radiotherapy treatments. The dosimetry of small radiation fields is not trivial due to the problems associated with lateral disequilibrium and source occlusion and requires reliable quality assurance (QA). Ideally such a QA tool should provide high spatial resolution, minimal beam perturbation and real time fast measurements. Many different types of silicon diode arrays are used for QA in radiotherapy; however, their application in small filed dosimetry is limited, in part, due to a lack of spatial resolution...
December 10, 2016: Medical Physics
https://www.readbyqxmd.com/read/28151727/contour-scanning-for-penumbra-improvement-in-pencil-beam-scanned-proton-therapy
#9
Gabriel Meier, Dominic Leiser, Rico Besson, Alexandre Mayor, Sairos Safai, Damien Weber, Antony Lomax
Proton therapy, especially in the form of pencil beam scanning (PBS), allows for the delivery of highly conformal dose distributions for complex tumor geometries. However, due to scattering of protons inside the patient, lateral dose gradients cannot be arbitrarily steep, which is of importance in cases with organs at risk (OARs) in close proximity to or overlapping planning target volumes (PTVs). In the PBS approach, physical pencil beams are planned using a regular grid orthogonal to the beam direction. In this work, we propose an alternative to this commonly used approach, by defining pencil beams on an irregular grid which is concentric to the target contour...
February 2, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28137900/rare-presentation-of-brodie-s-abscess-in-the-acromion-process-and-the-value-of-the-penumbra-sign
#10
Jelle Gorter, Kyrill Rykov, Pieter Ott, Jos J A M van Raay
A 17-year-old male patient presented with a swelling on his right shoulder 1 week after a fall. MRI revealed a superficial fluid collection of the acromion and trapezius muscle, with slight enhancement of the wall. The swelling burst open spontaneously after failed conservative therapy and was treated with surgical drainage and antibiotics. Tissue cultures showed a Staphylococcus aureus 1 year later, he presented with local red discolouration and a recurrent painful swelling that fluctuated at palpation...
January 30, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28129665/optimization-of-the-mechanical-collimation-for-minibeam-generation-in-proton-minibeam-radiation-therapy
#11
Consuelo Guardiola, Cécile Peucelle, Yolanda Prezado
PURPOSE: The dose tolerances of normal tissues continue to be the main barrier in radiation therapy. To lower it, a novel concept based on a combination of proton therapy and the use of arrays of parallel and thin beams has been recently proposed: proton minibeam radiation therapy (pMBRT). It allies the inherent advantages of protons with the remarkable normal tissue preservation observed when irradiated with submillimetric spatially fractionated beams. Due to multiple Coulomb scattering, the tumor receives a homogeneous dose distribution, while normal tissues in the beam's path benefit from the spatial fractionation of the dose...
January 27, 2017: Medical Physics
https://www.readbyqxmd.com/read/28129172/mr360-mixed-reality-rendering-for-360-%C3%A2-panoramic-videos
#12
Taehyun Rhee, Lohit Petikam, Benjamin Allen, Andrew Chalmers
This paper presents a novel immersive system called MR360 that provides interactive mixed reality (MR) experiences using a conventional low dynamic range (LDR) 360 (°) panoramic video (360-video) shown in head mounted displays (HMDs). MR360 seamlessly composites 3D virtual objects into a live 360-video using the input panoramic video as the lighting source to illuminate the virtual objects. Image based lighting (IBL) is perceptually optimized to provide fast and believable results using the LDR 360-video as the lighting source...
January 23, 2017: IEEE Transactions on Visualization and Computer Graphics
https://www.readbyqxmd.com/read/28126476/optimization-of-brain-metastases-radiotherapy-with-tomohda
#13
Slav Yartsev, Glenn Bauman
An upgrade of the helical tomotherapy technology by introducing variable fan-field width (dynamic jaws) reduced the penumbra in superior-inferior direction for the target. Possible implementation of this upgrade even for the cases of the targets with different dose prescriptions is proposed. An example of brain metastasis in proximity to the optical apparatus in need of the whole brain irradiation of 30 Gy and higher dose to the lesion is considered.
January 23, 2017: Medical Dosimetry: Official Journal of the American Association of Medical Dosimetrists
https://www.readbyqxmd.com/read/28123421/effect-of-ephrin-b2-on-the-expressions-of-angiopoietin-1-and-2-after-focal-cerebral-ischemia-reperfusion
#14
Hui Xiao, Qing Huang, Jia-Qi Wang, Qing-Qing Deng, Wen-Ping Gu
Ephrin-B2 has been shown to participate in angiogenesis, but the underlying mechanisms involved remain unclear. In this study, a rat model of focal cerebral ischemia was prepared by focal middle cerebral artery occlusion, followed by 24-hour reperfusion. Then, ephrin-B2 protein was administered intracerebroventricularly for 3 consecutive days via a micro-osmotic pump. Western blot assay and quantitative real-time reverse transcription PCR demonstrated the expression levels of angiopoietin-1 (Ang-1) mRNA and protein in the penumbra cortex of the ephrin-B2 treated group were decreased at day 4 after reperfusion, and increased at day 28, while the expression levels of angiopoietin-2 (Ang-2) were highly up-regulated at all time points tested...
November 2016: Neural Regeneration Research
https://www.readbyqxmd.com/read/28114983/panaxatriol-saponins-promotes-angiogenesis-and-enhances-cerebral-perfusion-after-ischemic-stroke-in-rats
#15
Zhen Hui, Du-Juan Sha, Su-Lei Wang, Chao-Sheng Li, Jian Qian, Jing-Qing Wang, Yang Zhao, Jing-Hua Zhang, Hong-Yu Cheng, Hui Yang, Lin-Jie Yu, Yun Xu
BACKGROUND: Panaxatriol saponins (PTS), an extract from the traditional Chinese herb Panax notoginseng, which has been used to treat ischemic stroke for many years in China. However, the mechanism underlying the effects of PTS remains unclear. This study aimed to determine whether PTS can protect against ischemic brain injury by promoting angiogenesis and to explore the possible mechanism by which it promotes angiogenesis. METHODS: Middle cerebral artery occlusion (MCAO) was induced in rats, and neurological deficit scores and brain infarct volumes were assessed...
January 23, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28103599/evaluations-of-intravenous-administration-of-cd34-human-umbilical-cord-blood-cells-in-a-mouse-model-of-neonatal-hypoxic-ischemic-encephalopathy
#16
Makiko Ohshima, Akihiko Taguchi, Yoshiaki Sato, Yuko Ogawa, Satoshi Saito, Kenichi Yamahara, Masafumi Ihara, Mariko Harada-Shiba, Tomoaki Ikeda, Tomohiro Matsuyama, Masahiro Tsuji
Several cell therapies have been explored as novel therapeutic strategies for neonatal encephalopathy because the benefits of current treatments are limited. We previously reported that intravenous administration of human umbilical cord blood (hUCB) CD34+ cells (hematopoietic stem cells/endothelial progenitor cells) at 48 h after insult exerts therapeutic effects in neonatal mice with stroke, i.e., permanent middle cerebral artery occlusion. Although neonatal stroke and hypoxic-ischemic encephalopathy (HIE) are grouped under the term "neonatal encephalopathy," their pathogenesis differs...
January 20, 2017: Developmental Neuroscience
https://www.readbyqxmd.com/read/28079313/postischemic-inflammation-in-acute-stroke
#17
REVIEW
Simone Vidale, Arturo Consoli, Marco Arnaboldi, Domenico Consoli
Cerebral ischemia is caused by arterial occlusion due to a thrombus or an embolus. Such occlusion induces multiple and concomitant pathophysiological processes that involve bioenergetic failure, acidosis, loss of cell homeostasis, excitotoxicity, and disruption of the blood-brain barrier. All of these mechanisms contribute to neuronal death, mainly via apoptosis or necrosis. The immune system is involved in this process in the early phases after brain injury, which contributes to potential enlargement of the infarct size and involves the penumbra area...
January 2017: Journal of Clinical Neurology
https://www.readbyqxmd.com/read/28078626/time-course-investigation-of-blood-brain-barrier-permeability-and-tight-junction-protein-changes-in-a-rat-model-of-permanent-focal-ischemia
#18
Peng Liu, Rui Zhang, Danyang Liu, Jinling Wang, Chunling Yuan, Xuemei Zhao, Yinjie Li, Xuefei Ji, Tianyan Chi, Libo Zou
Permanent middle cerebral artery occlusion (pMCAO) is an animal model that is widely used to simulate human ischemic stroke. However, the timing of the changes in the expression of tight junction (TJ) proteins and synaptic proteins associated with pMCAO remain incompletely understood. Therefore, to further explore the characteristics and mechanisms of blood-brain barrier (BBB) damage during cerebral ischemic stroke, we used a pMCAO rat model to define dynamic changes in BBB permeability within 120 h after ischemia in order to examine the expression levels of the TJ proteins claudin-5 and occludin and the synaptic proteins synaptophysin (SYP) and postsynaptic density protein 95 (PSD95)...
January 11, 2017: Journal of Physiological Sciences: JPS
https://www.readbyqxmd.com/read/28068417/preserved-collateral-blood-flow-in-the-endovascular-m2cao-model-allows-for-clinically-relevant-profiling-of-injury-progression-in-acute-ischemic-stroke
#19
Philip Little, Ola Kvist, Rikard Grankvist, Stefan Jonsson, Peter Damberg, Michael Söderman, Fabian Arnberg, Staffan Holmin
Interventional treatment regimens have increased the demand for accurate understanding of the progression of injury in acute ischemic stroke. However, conventional animal models severely inhibit collateral blood flow and mimic the malignant infarction profile not suitable for treatment. The aim of this study was to provide a clinically relevant profile of the emergence and course of ischemic injury in cases suitable for acute intervention, and was achieved by employing a M2 occlusion model (M2CAO) that more accurately simulates middle cerebral artery (MCA) occlusion in humans...
2017: PloS One
https://www.readbyqxmd.com/read/28065778/protective-effects-of-tongxinluo-on-cerebral-ischemia-reperfusion-injury-related-to-connexin-43-calpain-ii-bax-caspase-3-pathway-in-rat
#20
Xiao Cheng, Zijun Hou, Jingbo Sun, Yan Huang, Lixin Wang, Ziyi Zhou, Li-Hua Zhou, Yefeng Cai
ETHNOPHARMACOLOGICAL RELEVANCE: Tongxinluo (TXL) is a multifunctional traditional Chinese medicine and has been widely used in the treatment of cardiovascular and cerebrovascular diseases. Numerous studies demonstrate that TXL is a novel neuroprotective drug, however, the mechanisms are largely unknown. AIM OF THE STUDY: we aimed to demonstrate the protective effect of TXL on cerebral ischemia/reperfusion (I/R) injury and provide the evidence for the involvement of Connexin 43/Calpain II/ Bax/Caspase-3 pathway in TXL-mediated neuroprotection...
January 5, 2017: Journal of Ethnopharmacology
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