Search results for "cerebrovascular circulation"
showing 10 items of 158 documents
Role of non-coding RNAs in age-related vascular cognitive impairment: An overview on diagnostic/prognostic value in Vascular Dementia and Vascular Pa…
2020
Age is the pivotal risk factor for different common medical conditions such as cardiovascular diseases, cancer and dementia. Among age-related disorders, cardiovascular and cerebrovascular diseases, represent the leading causes of premature mortality strictly related to vascular ageing, a pathological condition characterized by endothelial dysfunction, atherosclerosis, hypertension, heart disease and stroke. These features negatively impact on the brain, owing to altered cerebral blood flow, neurovascular coupling and impaired endothelial permeability leading to cerebrovascular diseases (CVDs) as Vascular Dementia (VD) and Parkinsonism (VP). It is an increasing opinion that neurodegenerativ…
Vascular pathology: Cause or effect in Alzheimer disease?
2018
Introduction: Alzheimer disease (AD) is the main cortical neurodegenerative disease. The incidence of this disease increases with age, causing significant medical, social and economic problems, especially in countries with ageing populations. Objective: This review aims to highlight existing evidence of how vascular dysfunction may contribute to cognitive impairment in AD, as well as the therapeutic possibilities that might arise from this evidence. Development: The vascular hypothesis emerged as an alternative to the amyloid cascade hypothesis as an explanation for the pathophysiology of AD. This hypothesis locates blood vessels as the origin for a variety of pathogenic pathways that lead …
Deciphering Alzheimer’s Disease Pathogenic Pathway: Role of Chronic Brain Hypoperfusion on p-Tau and mTOR
2021
This review examines new biomolecular findings that lend support to the hemodynamic role played by chronic brain hypoperfusion (CBH) in driving a pathway to Alzheimer’s disease (AD). CBH is a common clinical feature of AD and the current topic of intense investigation in AD models. CBH is also the basis for the vascular hypothesis of AD which we originally proposed in 1993. New biomolecular findings reveal the interplay of CBH in increasing tau phosphorylation (p-Tau) in the hippocampus and cortex of AD mice, damaging fast axonal transport, increasing signaling of mammalian target of rapamycin (mTOR), impairing learning-memory function, and promoting the formation of neurofibrillary tangles…
Collapsibility of the internal jugular veins in the lateral decubitus body position: A potential protective role of the cerebral venous outflow again…
2019
Recent research has revealed that patients with neurodegenerative disease sleep longer in the supine position, while healthy controls prefer sleeping in the lateral decubitus position. Thus, sleeping in the lateral position seems to be protective against neurodegeneration. It has also been suggested that a protective role of this body position could be associated with better cerebral venous drainage in this body position, which results in more active glymphatic system of the brain (the system responsible for clearance of the cerebral tissue from waste products, e.g. amyloid-β). Since no published evidence exists regarding venous outflow from the cranial cavity in the lateral decubitus posit…
Neurotrophic and neuroprotective effects of muscle contraction
2016
Background: Physical activity has been shown to be associated with reduced risk of coronary heart disease but the same effect seems to be produced in neurological diseases. Objective: In this review, we focused on the interplay between physical activity and some neurological conditions (Stroke, dementia, epilepsy, headache, Parkinson’ s disease, amyotrophic lateral sclerosis, multiple sclerosis, insomnia, depression and anxiety) with the aim of describing the potential role of physical activity in the prevention of such diseases and the physiological mechanisms involved in these processes. Results: Despite a growing body of evidence which reveals that physical activity is able to reduce the…
Anaesthetic techniques to prevent perioperative stroke.
2013
Different techniques and interventions that can be used by an anaesthesiologist to minimize the perioperative stroke risk are summarized.The most important risk factors for perioperative stoke are not modifiable, for example previous stroke or renal failure, but they can be used to identify patients with a high risk for perioperative stroke. The antiplatelet therapy should be continued in patients with a high risk for cardiovascular thrombosis. This might be true even for operations in which bleeding should be strictly avoided such as eye surgery. One of the most recent neuroprotective approaches is the remote ischaemic preconditioning.Perioperative stroke increases morbidity and mortality …
Brain tissue pO2 related to SjvO2, ICP, and CPP in severe brain injury
2000
The aim of this report is to present first experience in comparing the course of brain tissue oxygen pressure values (PtiO2) to changes in jugular vein oxygen saturation (SjvO2), intracranial pressure (ICP), and cerebral perfusion pressure (CPP) after severe brain injury. PtiO2 monitoring was done using a polarographic Clark type microcatheter (LICOX pO2 probe) (GMS, Kiel, Germany) with a diameter of 0.5 mm and a sensitive area 7.9 mm long inserted in a right frontal position. The microcatheter was connected to a LICOX pO2 device. A fiber-optic catheter was used to measure SjvO2 and placed into the right internal jugular vein. The ICP monitoring was performed with a fiber-optic intraparench…
RCBF-quantification with 99mTc-HMPAO-SPECT: theory and first results.
1989
The activity concentrations of 99mTc-HMPAO in brain after intravenous injection were evaluated in 25 patients using SPECT. With additional first pass studies of heart and brain with the short lived isotope 195mAu, the cardiac output and the mean cerebral transit times of the patients were measured a short time before the HMPAO injection. The time dependence of 99mTc-HMPAO activity in the brain was registered during the first 5 min after injection over both hemispheres. Using a simplified three compartment model it was possible to calculate the mean retention fraction of HMPAO in brain from the time activity curves. It could be shown that the regional cerebral blood flow in ml/min per 100 g …
Cerebral blood flow, computerized tomography and angiography in 562 cases of cerebrovascular insufficiency
1987
The measurement of cerebral blood flow (CBF) in addition to cerebral computerized tomography (CT) and angiography is most reliable in cases of transient ischemic attacks (TIA) and prolonged reversible ischemic neurologic deficits (PRIND). Alterations of CBF can be detected in symptom-free intervals. The cerebrovascular reactivity to CO2 stimulus is regarded as an especially suitable tool to prove the cerebrovascular reserve. If it is diminished, cerebral angiography should be carried out since it will often show major obstructive lesions. Angiography shows no sure correlation between CBF and collateral circulation. Strong opthalmic pathways in unilateral occlusion of the internal carotid ar…
Correlation of cerebral blood flow and MCA flow velocity measured in healthy volunteers during acetazolamide and CO2 stimulation
1995
Abstract The assessment of the cerebrovascular reserve capacity (RC) has become a widely used tool in the management of cerebrovascular disease. Discrepancies become obvious, however, if results obtained with different methods are compared. Aim of the present study, therefore, was to compare blood velocity and cerebral perfusion data in the same group of healthy test persons. In 32 volunteers regional cerebral blood flow (rCBF) was measured with the 133 Xe-inhalation method. F1 as grey matter flow and the initial slope index (ISI) were computed. Simultaneously flow velocity in the middle cerebral artery (V MCA ) was assessed by transcranial Doppler sonography (TCD). Measurements were perfor…