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https://www.readbyqxmd.com/read/27927624/cerebral-blood-flow-autoregulation-in-ischemic-heart-failure
#1
Juliana R Caldas, Ronney B Panerai, Victoria Jane Haunton, Juliano P Almeida, Graziela S R Ferreira, Ligia Camara, Ricardo de Carvalho Nogueira, Edson Bor-Seng-Shu, Marcelo L Oliveira, Raphaela R V Groehs, Larissa Ferreira-Santos, Manoel Jacobsen Teixeira, Filomena R B G Galas, Thompson G Robinson, Fabio B Jatene, Ludhmila A Hajjar
Patients with ischemic heart failure (iHF) have a high risk of neurological complications such as cognitive impairment and stroke. We hypothesized that iHF patients have a higher incidence of impaired dynamic cerebral autoregulation (dCA). Adult patients with iHF and healthy volunteers were included. Cerebral blood flow velocity (CBFV, transcranial Doppler, middle cerebral artery), end-tidal CO2 (capnography), and arterial blood pressure (Finometer) were continuously recorded supine for five minutes at rest...
December 7, 2016: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology
https://www.readbyqxmd.com/read/27911329/comparison-of-model-based-indices-of%C3%A2-cerebral-autoregulation-and-vasomotor-reactivity-using-transcranial-doppler-versus-near-infrared-spectroscopy-in%C3%A2-patients-with-amnestic-mild-cognitive-impairment
#2
Vasilis Z Marmarelis, Dae C Shin, Takashi Tarumi, Rong Zhang
We recently introduced model-based "physiomarkers" of dynamic cerebral autoregulation and CO2 vasomotor reactivity as an aid for diagnosis of early-stage Alzheimer's disease (AD) [1], where significant impairment of dynamic vasomotor reactivity (DVR) was observed in early-stage AD patients relative to age-matched controls. Milder impairment of DVR was shown in patients with amnestic mild cognitive impairment (MCI) using the same approach in a subsequent study [2]. The advocated approach utilizes subject-specific data-based models of cerebral hemodynamics to quantify the dynamic effects of resting-state changes in arterial blood pressure and end-tidal CO2 (the putative inputs) upon cerebral blood flow velocity (the putative output) measured at the middle cerebral artery via transcranial Doppler (TCD)...
November 28, 2016: Journal of Alzheimer's Disease: JAD
https://www.readbyqxmd.com/read/27909201/infarct-pattern-and-collateral-status-in-adult-moyamoya-disease-a-multimodal-magnetic-resonance-imaging-study
#3
Dong Yeop Kim, Jeong Pyo Son, Je Young Yeon, Gyeong-Moon Kim, Jong-Soo Kim, Seung-Chyul Hong, Oh Young Bang
BACKGROUND AND PURPOSE: Moyamoya disease (MMD) is a unique cerebrovascular disease characterized by the progressive stenosis of large intracranial arteries and a hazy network of basal collaterals, called moyamoya vessels. Although hemodynamic studies have been applied in MMD patients, the mechanisms of stroke in MMD are still unclear. The present study evaluated the infarct pattern and collateral status using multimodal magnetic resonance imaging in MMD patients. METHODS: Adult MMD patients with acute ischemic stroke were prospectively recruited, and infarct pattern on diffusion-weighted imaging was evaluated...
December 1, 2016: Stroke; a Journal of Cerebral Circulation
https://www.readbyqxmd.com/read/27892636/impaired-retinal-vasoreactivity-an-early-marker-of-stroke-risk-in-diabetes
#4
Kerstin Bettermann, Julia Slocomb, Vikram Shivkumar, David Quillen, Thomas W Gardner, Mary E Lott
Diabetes is a common cause of small vessel disease leading to stroke and vascular dementia. While the function and structure of large cerebral vessels can be easily studied, the brain's microvasculature remains difficult to assess. Previous studies have demonstrated that structural changes in the retinal vessel architecture predict stroke risk, but these changes occur at late disease stages. Our goal was to examine whether retinal vascular status can predict cerebral small vessel dysfunction during early stages of diabetes...
November 28, 2016: Journal of Neuroimaging: Official Journal of the American Society of Neuroimaging
https://www.readbyqxmd.com/read/27881556/nitrite-and-s-nitrosohemoglobin-exchange-across-the-human-cerebral-and-femoral-circulation-relationship-to-basal-and-exercise-blood-flow-responses-to-hypoxia
#5
Damian M Bailey, Peter Rasmussen, Morten Overgaard, Kevin A Evans, Aske M Bohm, Thomas Seifert, Patrice Brassard, Morten Zaar, Henning B Nielsen, Peter Raven, Niels H Secher
BACKGROUND: -The mechanisms underlying red blood cell (RBC)-mediated hypoxic vasodilation remain controversial with separate roles for nitrite (NO2(-)) and S-nitrosohemoglobin (SNO-Hb) widely contested given their ability to transduce nitric oxide (NO) bioactivity within the microcirculation. To establish their relative contribution in vivo, we quantified arterial-venous (a-v) concentration gradients across the human cerebral and femoral circulation at rest and during exercise, an ideal model system characterized by physiological extremes of O2 tension and blood flow...
November 15, 2016: Circulation
https://www.readbyqxmd.com/read/27880813/transcranial-doppler-based-surrogates-for-cerebral-blood-flow-a-statistical-study
#6
Joseph Hart, Vera Novak, Charles Saunders, Pierre A Gremaud
It is commonly assumed that perfusion in a given cerebral territory can be inferred from Blood Flow Velocity (BFV) measurements in the corresponding stem artery. In order to test this hypothesis, we construct a cerebral blood flow (CBF) estimator based on transcranial Doppler (TCD) blood flow velocity and ten other easily available patient characteristics and clinical parameters. A total of 261 measurements were collected from 88 older patients. The estimator is based on local regression (Random Forest). Its performance is analyzed against baseline CBF from 3-D pseudocontinuous arterial spin labeling (pCASL) magnetic resonance imaging (MRI)...
2016: PloS One
https://www.readbyqxmd.com/read/27875362/relationship-between-hiv-infection-antiretroviral-therapy-inflammatory-markers-and-cerebrovascular-endothelial-function-among-adults-in-urban-china
#7
Felicia C Chow, Yanling Li, Yinghuan Hu, Joy Chan, Huanling Wang, Weihai Xu, Richard W Price, Farzaneh A Sorond, Taisheng Li
BACKGROUND: Cerebrovascular risk is increased in people living with HIV infection compared with age-matched uninfected individuals. Cerebrovascular endothelial dysfunction related to antiretroviral therapy and inflammation may contribute to higher stroke risk in HIV infection. METHODS: We compared cerebral vasoreactivity-a measure of cerebrovascular endothelial function assessed by the breath holding index (BHI) using transcranial Doppler ultrasound-between virologically suppressed Chinese HIV-infected individuals followed in an HIV clinic in Beijing, China and uninfected controls...
November 21, 2016: Journal of Acquired Immune Deficiency Syndromes: JAIDS
https://www.readbyqxmd.com/read/27866915/trends-in-transcranial-doppler-monitoring-in-aneurysmal-subarachnoid-hemorrhage-a-10-year-analysis-of-the-nationwide-inpatient-sample
#8
Gyanendra Kumar, Karen C Albright, John P Donnelly, Angela Hays Shapshak, Mark R Harrigan
BACKGROUND: Transcranial Doppler (TCD) is endorsed by national guidelines for use in aneurysmal subarachnoid hemorrhage (aSAH) for surveillance of cerebral vasospasm (CV). However, nationwide data on utilization of TCD for CV detection and monitoring in aSAH are lacking. METHODS: Analysis of nationwide trends in TCD prevalence was performed using Nationwide Inpatient Sample (NIS) data from 2002 to 2011. Raw counts were converted into weighted counts, which were used to generate national estimates...
November 17, 2016: Journal of Stroke and Cerebrovascular Diseases: the Official Journal of National Stroke Association
https://www.readbyqxmd.com/read/27857223/non-high-density-lipoprotein-cholesterol-levels-on-the-risk-of-asymptomatic-intracranial-arterial-stenosis-a-result-from-the-apac-study
#9
Jianwei Wu, Anxin Wang, Xin Li, Shouling Wu, Xingquan Zhao
Intracranial arterial stenosis (ICAS) is an important cause of ischemic stroke and transient ischemic attack (TIA), and the correlation between the plasma non-high density cholesterol (non-HDLC) levels and ICAS, especially asymptomatic ICAS (AICAS) is not clear. The Asymptomatic Polyvascular Abnormalities Community(APAC) study is a community-based, prospective, long-term follow-up observational study. 3387 participants were enrolled in this study. The diagnosis of AICAS was made by transcranial Doppler ultrasonography...
November 18, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27857051/elevation-of-the-acth-cortisol-ratio-in-female-opioid-dependent-patients-a-biomarker-of-aging-and-correlate-of-metabolic-and-immune-activation
#10
(no author information available yet)
BACKGROUND: Whilst the hypothalamic-pituitary-adrenal (HPA) Axis is a major stress axis, and is necessarily perturbed in opioid dependency, and stress is a major contributor to aging mechanisms, the HPA axis has not been studied in opioid dependency in an age-dependent manner. OBJECTIVE: Hypothesis - Differences in age dependent levels of HPA components. DESIGN: Cross-sectional comparison of general medical and opioid dependent patients (ODP, GMP)...
September 18, 2016: Neuro Endocrinology Letters
https://www.readbyqxmd.com/read/27856223/-transcient-ischemic-attack-a-rare-manifestation-of-eagle-syndrome
#11
J Usseglio, F Macian Montoro, S Martin, J Lerat, J Laloze, A Taibi, J Brie
INTRODUCTION: Clinical presentation of Eagle syndrome (ES) is very variable and non-specific, making its diagnosis difficult. It is usually limited to pain. Transient neurological manifestations are exceptional. We report one case in which the diagnosis of ES has been made based on neurological events occurring during left anterolateral head bending, without pain. OBSERVATION: A 47-year-old man presented with transient neurological events progressing since two years, half-right body paresthesia and reduced field of vision on the left side type, triggered by left anterolateral head flexion and regressive in neutral position...
December 2016: Revue de Stomatologie, de Chirurgie Maxillo-faciale et de Chirurgie Orale
https://www.readbyqxmd.com/read/27850447/809-transcranial-doppler-assessment-in-mild-pediatric-traumatic-brain-injury
#12
Jake Deines, Jianhong Chang, Karin Reuter-Rice
No abstract text is available yet for this article.
December 2016: Critical Care Medicine
https://www.readbyqxmd.com/read/27843693/treatment-and-imaging-of-intracranial-atherosclerotic-stenosis-current-perspectives-and-future-directions
#13
REVIEW
Ido R van den Wijngaard, Ghislaine Holswilder, Marianne A A van Walderveen, Ale Algra, Marieke J H Wermer, Osama O Zaidat, Jelis Boiten
BACKGROUND AND PURPOSE: Intracranial atherosclerosis is a common cause of stroke worldwide. It results in ischemic stroke due to different mechanisms including artery-to-artery embolism, in situ thrombo-occlusion, occlusion of perforating arteries, and hemodynamic failure. In this review, we present an overview of current treatment and imaging modalities in intracranial atherosclerotic stenosis. METHODS: PubMed was searched for relevant articles in English that evaluated the treatment and imaging of intracranial atherosclerotic stenosis (ICAS)...
November 2016: Brain and Behavior
https://www.readbyqxmd.com/read/27837190/hyperoxia-results-in-increased-aerobic-metabolism-following-acute-brain-injury
#14
Arnab Ghosh, David Highton, Christina Kolyva, Ilias Tachtsidis, Clare E Elwell, Martin Smith
Acute brain injury is associated with depressed aerobic metabolism. Below a critical mitochondrial pO2 cytochrome c oxidase, the terminal electron acceptor in the mitochondrial respiratory chain, fails to sustain oxidative phosphorylation. After acute brain injury, this ischaemic threshold might be shifted into apparently normal levels of tissue oxygenation. We investigated the oxygen dependency of aerobic metabolism in 16 acutely brain-injured patients using a 120-min normobaric hyperoxia challenge in the acute phase (24-72 h) post-injury and multimodal neuromonitoring, including transcranial Doppler ultrasound-measured cerebral blood flow velocity, cerebral microdialysis-derived lactate-pyruvate ratio (LPR), brain tissue pO2 (pbrO2), and tissue oxygenation index and cytochrome c oxidase oxidation state (oxCCO) measured using broadband spectroscopy...
November 11, 2016: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/27837189/middle-cerebral-artery-diameter-changes-during-rhythmic-handgrip-exercise-in-humans
#15
J Verbree, Agt Bronzwaer, M A van Buchem, Mjap Daemen, J J van Lieshout, Mjp van Osch
Transcranial Doppler (TCD) sonography is a frequently employed technique for quantifying cerebral blood flow by assuming a constant arterial diameter. Given that exercise increases arterial pressure by sympathetic activation, we hypothesized that exercise might induce a change in the diameter of large cerebral arteries. Middle cerebral artery (MCA) cross-sectional area was assessed in response to handgrip exercise by direct magnetic resonance imaging (MRI) observations. Twenty healthy subjects (11 female) performed three 5 min bouts of rhythmic handgrip exercise at 60% maximum voluntary contraction, alternated with 5 min of rest...
November 11, 2016: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/27823712/sleep-apnea-syndrome-and-patent-foramen-ovale-a-dangerous-association-in-ischemic-stroke
#16
Silvia Tur, Mónica de la Peña, Bárbara Vives, Ana Belén Martínez, Arantza Gorospe, Inés Legarda, Maria José Torres, Carmen Jiménez, Joan B Soriano
BACKGROUND: The coexistence of patent foramen ovale (PFO) and sleep apnea syndrome (SAS) might be related to the pathogenesis of cryptogenic stroke (CS). We aimed to determine the prevalence of SAS in patients with cryptogenic stroke and PFO. METHODS: This is a prospective case-control study in which we included ischemic stroke patients consecutively admitted to our hospital's Acute Stroke Unit. Contrast transcranial Doppler (c-TCD) and sleep polygraphy within the first 72 h after stroke onset were performed to detect PFO and SAS...
September 2016: Sleep Medicine
https://www.readbyqxmd.com/read/27810458/effect-of-hyperoxia-on-cerebral-blood-flow-velocity-and-regional-oxygen-saturation-in-patients-operated-upon-for-severe-traumatic-brain-injury-the-influence-of-cerebral-blood-flow-autoregulation
#17
Sarasa Sahoo, Veena Sheshadri, Kamath Sriganesh, K R Madhsudana Reddy, M Radhakrishnan, G S Umamaheswara Rao
BACKGROUND: The effect of normobaric hyperoxia on brain oxygenation in the presence or absence of intact autoregulation has not been studied till now in acute traumatic brain injury (TBI). METHODS: In this prospective clinical investigation in fifty patients operated for severe TBI, cerebral blood flow (CBF) velocity in the middle cerebral artery (MCA) was measured using transcranial doppler (TCD). Regional cerebral oxygen saturation (rSO2) using near infra-red spectroscopy (NIRS) at three different inspired oxygen fractions (FiO2 of 0...
October 31, 2016: World Neurosurgery
https://www.readbyqxmd.com/read/27801780/preoperative-3d-fse-t1-weighted-mr-plaque-imaging-for-severely-stenotic-cervical-ica-accuracy-of-predicting-emboli-during-carotid-endarterectomy
#18
Yasushi Ogasawara, Yuiko Sato, Shinsuke Narumi, Makoto Sasaki, Shunrou Fujiwara, Masakazu Kobayashi, Kenji Yoshida, Yasuo Terayama, Kuniaki Ogasawara
The aim of the present study was to determine whether preoperative three-dimensional (3D) fast spin-echo (FSE) T1-weighted magnetic resonance (MR) plaque imaging for severely stenotic cervical carotid arteries could accurately predict the development of artery-to-artery emboli during exposure of the carotid arteries in carotid endarterectomy (CEA). Seventy-five patients underwent preoperative MR plaque imaging and CEA under transcranial Doppler ultrasonography of the ipsilateral middle cerebral artery. On reformatted axial MR image slices showing the maximum plaque occupation rate (POR) and maximum plaque intensity for each patient, the contrast ratio (CR) was calculated by dividing the internal carotid artery plaque signal intensity by the sternocleidomastoid muscle signal intensity...
October 27, 2016: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/27796172/risk-factors-between-intracranial-extracranial-atherosclerosis-and-anterior-posterior-circulation-stroke-in-ischaemic-stroke
#19
Yan Li, Yefeng Cai, Min Zhao, Jingbo Sun
OBJECTIVES: Atherosclerosis is an important cause of stroke and remains a challenge for stroke prevention. Risk factors involved in atherosclerotic stroke and anterior and posterior circulation strokes (ACS and PCS, respectively) are different. The purpose of this study is to investigate differences in risk factors between intracranial and extracranial atherosclerosis (ICAS and ECAS), ACS and PCS, and ICAS/ECAS with ACS/PCS in a Chinese acute ischaemic stroke population. METHODS: We analysed 551 ischaemic stroke patients who had been enrolled between August 2005 and July 2008...
October 31, 2016: Neurological Research
https://www.readbyqxmd.com/read/27790125/a-case-of-turner-syndrome-with-multiple-embolic-infarcts
#20
Cindy W Yoon, Eungseok Lee, Byung-Nam Yoon, Hee-Kwon Park, Joung-Ho Rha
Only a few cases of Turner syndrome (TS) with ischemic stroke have been reported. Various arteriopathies of the cerebral arteries, including fibromuscular dysplasia, congenital hypoplasia, moyamoya syndrome, and premature atherosclerosis have been assumed to be the cause of ischemic stroke in TS. There has been no case report of a TS patient presenting with an embolic stroke pattern without any cerebral arteriopathy. A 28-year-old woman with TS was referred to our hospital because of abnormal brain magnetic resonance imaging (MRI) findings...
September 2016: Case Reports in Neurology
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