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Brain blood flow

Susan Y S Feng, Jacob H Hollis, Thilini Samarasinghe, David J Phillips, Shripada Rao, Victor Y H Yu, Adrian M Walker
As the comparative pathophysiology of perinatal infection in the fetus and newborn is uncertain, this study contrasted the cerebral effects of endotoxemia in conscious fetal sheep and newborn lambs. Responses to intravenous bacterial endotoxin (lipopolysaccharide, LPS) or normal saline were studied on three consecutive days in fetal sheep (LPS 1 μg/kg, n = 5; normal saline n = 5) and newborn lambs (LPS 2 μg/kg, n = 10; normal saline n = 5). Cerebro-vascular function was assessed by monitoring cerebral blood flow (CBF) and cerebral vascular resistance (CVR) over 12 h each day, and inflammatory responses were assessed by plasma TNF alpha (TNF-α), nitrate and nitrite concentrations...
February 2019: Physiological Reports
Giampiero Giovacchini, Elisabetta Giovannini, Elisa Borsò, Patrizia Lazzeri, Mattia Riondato, Rossella Leoncini, Valerio Duce, Andrea Ciarmiello
Neuropathological and clinical evidence indicates that the clinical expression of Alzheimer's disease (AD) occurs as neuropathology exceeds the brain reserve capacity. The brain or cognitive reserve (BCR) hypothesis states that high premorbid intelligence, education, and an active and stimulating lifestyle provide reserve capacity, which acts as a buffer against the cognitive deficits due to accumulating neuropathology. Neuroimaging studies that assessed the BCR hypothesis are critically reviewed with emphasis on study design and statistical analysis...
February 19, 2019: Journal of Cellular Physiology
I B Sokolova, G I Lobov
Intracerebral transplantation of mesenchymal stem cells to 6- and 12-month-old SHR rats induced angiogenesis in the pia mater. In 6-months-old SHR rats, perfusion in the brain tissue after cell transplantation considerably increased, while in 12-month-old rats it remained practically unchanged. We also observed marked activation of regulatory processes in the cerebral vascular system, most pronounced in 12-month-old rats. Neurogenic and myogenic tone of cerebral vessels increased significantly, while endothelium-dependent tone slightly decreased...
February 19, 2019: Bulletin of Experimental Biology and Medicine
Ronaldo V Nunes, Marcelo B Reyes, Raphael Y de Camargo
The flow of information between different regions of the cortex is fundamental for brain function. Researchers use causality detection techniques, such as Granger causality, to infer connectivity among brain areas from time series. Generalized partial directed coherence (GPDC) is a frequency domain linear method based on vector autoregressive model, which has been applied in electroencephalography, local field potential, and blood oxygenation level-dependent signals. Despite its widespread usage, previous attempts to validate GPDC use oversimplified simulated data, which do not reflect the nonlinearities and network couplings present in biological signals...
February 19, 2019: Biological Cybernetics
Yasuyoshi Shimada, Masakazu Kobayashi, Kenji Yoshida, Kazunori Terasaki, Shunrou Fujiwara, Yoshitaka Kubo, Takaaki Beppu, Kuniaki Ogasawara
BACKGROUND: Hypoxic but viable neural tissue is seen on 1-(2-18F-fluoro-1-[hydroxymethyl]ethoxy) methyl-2-nitroimidazole (18F-FRP170) positron emission tomography (PET) in patients with chronic cerebral ischemia with a combination of misery perfusion and moderately reduced oxygen metabolism. Cognitive function sometimes improves after revascularization surgery in patients with chronic cerebral ischemia. OBJECTIVES: We used brain perfusion single-photon emission computed tomography (SPECT) and 18F-FRP170 PET to determine whether hypoxic tissue was reduced following the restoration of cerebral perfusion after carotid endarterectomy (CEA) in patients with severe stenosis of the cervical internal carotid artery (ICA) and whether the reduction in hypoxic tissue was associated with cognitive improvement...
February 15, 2019: Cerebrovascular Diseases
Debby Vreeken, Maximilian Wiesmann, Laura N Deden, Ilse A C Arnoldussen, Esther Aarts, Roy P C Kessels, Robert Kleemann, Eric J Hazebroek, Edo O Aarts, Amanda J Kiliaan
INTRODUCTION: Weight loss after bariatric surgery (BS) is often associated with improved cognition and structural brain recovery. However, improved cognition after BS is not always exhibited by patients, in fact, in some cases there is even a decline in cognition. Long-term consequences of BS weight loss, in terms of obesity and related diseases, can be hard to determine due to studies having short follow-up periods and small sample sizes.The aim of the BARICO study ( BA riatric surgery R ijnstate and Radboudumc neuro I maging and C ognition in O besity) is to determine the long-term effect of weight loss after BS on brain function and structure, using sensitive neuropsychological tests and (functional) MRI ((f)MRI)...
January 9, 2019: BMJ Open
Tatyana Gavrilchenko, Eleni Katifori
The structure of flow networks determines their function under normal conditions as well as their response to perturbative damage. Brain vasculature often experiences transient or permanent occlusions in the finest vessels, but it is not clear how these microclots affect the large-scale blood flow or to what extent they decrease functionality. Motivated by this, we investigate how flow is rerouted after the occlusion of a single edge in networks with a hierarchy in edge conductances. We find that in two-dimensional networks, vessels formed by highly conductive edges serve as barriers to contain the displacement of flow due to a localized perturbation...
January 2019: Physical Review. E
Jeremy F Wong, Craig A Simmons
Cell monolayers, including endothelial cells lining the vasculature and blood-brain barrier, and epithelial cells lining the lung airways and gut, form a semipermeable barrier across which transport of biomolecules is tightly regulated. The assessment of barrier function is therefore critical in in vitro models of barrier-forming tissues, including microfluidic organ-on-a-chip models. Cell monolayer barrier function is commonly assessed using a fluorescent tracer-based permeability assay in both conventional Transwell and organ-on-a-chip models, but this method requires laborious manual sampling, bulky instrumentation and offline sample processing...
February 19, 2019: Lab on a Chip
Isabel Fragata, Marta Alves, Ana Luísa Papoila, Ana Paiva Nunes, Patrícia Ferreira, Mariana Diogo, Nuno Canto-Moreira, Patrícia Canhão
BACKGROUND: Computed tomography (CT) perfusion has been studied as a tool to predict delayed cerebral ischemia (DCI) and clinical outcome in spontaneous subarachnoid hemorrhage (SAH). The purpose of the study was to determine whether quantitative CT perfusion performed within 72 hours after admission can predict the occurrence of DCI and clinical outcome as measured with a modified Rankin scale (mRS) at 3 months after ictus. METHODS: Cerebral perfusion was assessed in a prospective cohort of patients with acute SAH...
February 19, 2019: Neuroradiology Journal
Yi-Bin Xi, Xiao-Wei Kang, Ning Wang, Ting-Ting Liu, Yuan-Qiang Zhu, Guang Cheng, Kai Wang, Chen Li, Fan Guo, Hong Yin
BACKGROUND AND PURPOSE: Conventional magnetic resonance imaging (MRI) is sometimes difficult to distinguish primary central nervous system lymphoma (PCNSL) from other malignant brain tumors effectively. The study aimed to evaluate the diagnostic performance of arterial spin labeling (ASL) and dynamic contrast-enhanced (DCE)-derived permeability parameters to differentiate PCNSL from high-grade glioma (HGG) and brain metastasis. MATERIALS AND METHODS: Eight patients with PCNSL, twenty one patients with HGG and six brain metastasis underwent preoperative 3...
March 2019: European Journal of Radiology
Abhijit Nirwane, Jessica Johnson, Benjamin Nguyen, Jeffrey H Miner, Yao Yao
At the blood-brain barrier (BBB), laminin-α5 is predominantly synthesized by endothelial cells and mural cells. Endothelial laminin-α5 is dispensable for BBB maintenance under homeostatic conditions but inhibits inflammatory cell extravasation in pathological conditions. Whether mural cell-derived laminin-α5 is involved in vascular integrity regulation, however, remains unknown. To answer this question, we generated transgenic mice with laminin-α5 deficiency in mural cells (α5-PKO). Under homeostatic conditions, no defects in BBB integrity and cerebral blood flow (CBF) were observed in α5-PKO mice, suggesting that mural cell-derived laminin-α5 is dispensable for BBB maintenance and CBF regulation under homeostatic conditions...
February 18, 2019: Acta Neuropathologica Communications
Francesco Acerbi, Francesco Prada, Ignazio G Vetrano, Jacopo Falco, Giuseppe Faragò, Paolo Ferroli, Francesco DiMeco
BACKGROUND: Distal outflow occlusion and extracranial-intracranial bypass represent a possible option for the surgical management of complex middle cerebral artery (MCA) aneurysm. A limitation of distal clipping strategy combined to bypass relies on the difficulties in predicting intraoperatively the good blood flow supply to the brain territory distal to the aneurysm and the extent and speed of aneurysmal thrombosis. METHODS: The authors presented an innovative approach in which Contrast-enhanced US (CEUS) and indocyanine green video-angiography (ICG-VA) have been synergistically used to study the effect of distal clipping on the aneurysm flow and the parenchymal blood flow after the bypass...
February 15, 2019: World Neurosurgery
M V Turovskaya, S G Gaidin, V N Mal'tseva, V P Zinchenko, E A Turovsky
Cerebral blood flow disturbances lead to the massive death of brain cells. The death of >80% of cells is observed in hippocampal cell cultures after 40 min of oxygen and glucose deprivation (ischemia-like conditions, OGD). However, there are some populations of GABAergic neurons which are characterized by increased vulnerability to oxygen-glucose deprivation conditions. Using fluorescent microscopy, immunocytochemical assay, vitality tests and PCR-analysis, we have shown that population of GABAergic neurons are characterized by a different (faster) Ca2+ dynamics in response to OGD and increased basal ROS production under OGD conditions...
February 15, 2019: Molecular and Cellular Neurosciences
Carmen Rey-Santano, Victoria E Mielgo, Miguel A Gomez-Solaetxe, Fabrizio Salomone, Elena Gastiasoro, Begoña Loureiro
BACKGROUND: Nasal continuous-positive airway pressure (nCPAP) with the INSURE (INtubation-SURfactant-Extubation) or LISA (Less-Invasive Surfactant Administration) procedures are increasingly being chosen as the initial treatment for neonates with surfactant deficiency. Our objective was to compare the effects on cerebral oxygenation of different methods for surfactant administration: INSURE and LISA, using a nasogastric tube (NT) or a LISAcath® catheter, in spontaneously breathing SF-deficient newborn piglets...
February 18, 2019: Pediatric Pulmonology
Dimitrios Priftakis, Phivi Rondogianni, Ioannis Datseris
Crossed cerebellar diaschisis (CCD) represents the reduction of blood flow, metabolism, and oxygen consumption in the cerebellar hemisphere contralateral to a cerebral focal lesion. This phenomenon is the result of remote metabolic effects of cerebral lesions and it has been described since the first attempts for functional imaging of the brain, almost 40 years ago. Nevertheless, its clinical significance remains uncertain and new ways to use imaging of CCD for prognosis or assessment of novel therapies are being investigated...
January 2019: World Journal of Nuclear Medicine
C C Wang, H B Dong, F Ding, Y D Li, G Y Wang, H X Ding
Objective: To investigate the value of multiple parameters derived from intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and three-dimensional arterial spin labeling (3D-ASL) in Ki-67 labeling index (Ki-67 LI) and grading of human brain gliomas. Methods: From December 2015 to May 2018, 45 patients of gliomas confirmed by surgical pathology in Li Huili Hospital, Ningbo Medical Center were divided into low-grade group (20 cases of WHO grade Ⅱ) and high-grade group (12 cases of WHO grade Ⅲ, 13 cases of WHO grade Ⅳ), and the Ki-67 LI of glioma was obtained by immunohistochemistry...
January 29, 2019: Zhonghua Yi Xue za Zhi [Chinese medical journal]
Arnon Blum, Nina Pastukh, Rizak Sirchan, Nava Blum, Lev Chernikoff, Vladimir Vaispapir
BACKGROUND: Endothelial progenitor cells may have a role in ongoing endothelial repair. Impaired mobilization or depletion of these cells may contribute to progression of vascular disease. Our hypothesis was that endothelial progenitor cells would be suppressed in patients with acute cerebrovascular event based on our previous study that found severe endothelial dysfunction in those patients. OBJECTIVES: To study the ability of patients with acute stroke to build colonies of endothelial progenitor cells...
February 2019: Israel Medical Association Journal: IMAJ
Emiko Momoki, Tatsuo Fuchigami, Yuki Kasuga, Kaori Kimura, Wakako Ishii, Ayumi Fukuda, Yukihiko Fujita, Ichiro Morioka
BACKGROUND: Confusional migraine is a rare type of migraine presenting as an acute confusional state. However, the mechanism of this confusional state remains unclear. SUBJECT AND METHODS: We examined an 11-year-old girl with confusional migraine, using electroencephalography, brain magnetic resonance imaging, cerebrovascular magnetic resonance angiography, and single-photon emission computed tomography to investigate cerebral blood flow changes. RESULTS: Our findings revealed vessel narrowing in the left middle and posterior cerebral artery territory, indicating vasospasm and suggesting that the confusion was caused by hypoperfusion...
February 13, 2019: Brain & Development
Yuemei Zhao, Yanbai Xue, Yan Zhang, Weitao Li, Zhiy Qian
In vivo simultaneous monitoring of blood flow and changes of concentration of oxyhemoglobin (ΔHbO2 ) in brain is a key important method for the research of cerebrovascular disease. In this study, a new monitoring system, combining laser speckle contrast imaging method and spectral analysis method, was proposed, which could be utilized to measure the cerebral blood flow and ΔHbO2 on mice during traumatic brain injury. The principle of the present system was studied and the hardware platform of the detection system was built...
January 30, 2019: Zhongguo Yi Liao Qi Xie za Zhi, Chinese Journal of Medical Instrumentation
Christian Staehr, Rajkumar Rajanathan, Vladimir Matchkov
NEW FINDINGS: What is the topic of this review? This review considers the role of the Na,K-ATPase in cerebrovascular function and how it might be changed in familial hemiplegic migraine type 2 (FHM2). The primary focus will be involvement of the Na,K-ATPase isoforms in regulation of cerebrovascular tone. What advances does it highlight? The review discusses three overall distinct mechanisms whereby the Na,K-ATPase might be capable of regulating cerebrovascular tone. Furthermore, it discusses how changes in the Na,K-ATPase in cerebral arteries might affect brain perfusion and thereby be involved in the FHM2 pathology...
February 15, 2019: Experimental Physiology
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