Biomedical subjects

L Parnetti

Publications and source records attributed to L Parnetti.

98 records · Page 6Linked to original sources

PubMedDate not supplied

The effect of oxiracetam treatment on alterations of lipid metabolism in brain areas from spontaneously hypertensive rats.

It has been previously demonstrated that spontaneously hypertensive adult rats (SHR) develop severe hypertension and cerebrovascular lesions on drinking 1% NaCl from weaning and that the phospholipid metabolism in the whole brain is actively altered in these lesioned animals (SHR-NaCl) as compared to SHRs which drink only water and show only sporadic cerebrovascular lesions. We have now assayed the incorporation of labelled choline, ethanolamine, glycerol and arachidonic acid into the phospholipids from the cortex and hippocampus of SHR-water and SHR-NaCl at different time intervals from injection into the lateral ventricle of the brain. A noticeable decrease of both choline and arachidonate specific activity (SA) in the phospholipids was found in the cortex and hippocampus (where the effect is most evident) from SHR-NaCl. Based on the literature and the data obtained, we suggest that in SHR-NaCl brain areas a release of choline and fatty acid also occurs from choline glycerophospholipids as a consequence of the cerebrovascular lesions caused by NaCl treatment. Even if a relatively minor loss of the amount of the lipids studied is evident from our results as compared to their entire pool, this change may be quite important if it causes a modification of the lipidic bilayer in excitable membranes. In a parallel group of SHR-NaCl animals, treated with the nootropic drug oxiracetam, we observed that the metabolic utilization of the precursors was completely restored. These experimental data favour the hypothesis that oxiracetam is effective in stimulating the phospholipid metabolism rate at levels even higher than those of the SHR-water animals.

Animals↗

PubMedDate not supplied

Secondary prevention of cardioembolic stroke: oldest and newest promises.

Atrial fibrillation (AF) is the most common cause of cardioembolism. An update on secondary prevention strategies used to protect from the risk of stroke AF patients is presented. The main line of actions of stroke prevention in AF are antithrombotics (anticoagulant or antiplatelet), antiarrhythmics (for rate control and sinus rhythm restore), mechanical means (for occlusion of the left atrial appendage or protection of the internal carotid artery from emboli). Classic pharmacological prevention with K vitamin Kantagonists such as warfarin may be overcome by direct thrombin inhibitors like ximelagatran and melagatran. New ablation technologies promise to cure, at least a part of Nonvalvolae AF in the community, restoring sinus rhythm. Recent achievements on endovascular procedures deploying carotid artery implants provide an opportunity to divert emboli to nonhazardous locations, whereas cardiac devices can seal left atrial appendages and avoid risk of clot migration in the blood stream. In the next decade, the challenge will be to understand competitiveness between old and new drugs with endovascular implants.

Anti-Arrhythmia Agents↗

PubMedDate not supplied

Multimodal use of computed tomography in early acute stroke, part 2.

Computed tomography (CT) scan remains the most widely technique in the cerebrovascular emergency, as it is largely available, minimally invasive, fast, cheap and reliable. Noncontrast enhanced CT (NeCT) imaging can show early signs of infarction in ischemic stroke; however, it could not show if the ischemic tissue is irreversibly damaged. CT perfusion (CTP) imaging has been shown to predict stroke location and size and can provide information about ischemic cerebral parenchyma not definitively compromised. CT angiography (CTA) could highlight stenosis or occlusion both in intracranial and extracranial vessels. By combining NeCT, CTP, and CTA the entire cerebrovascular axis can be imaged during acute stroke. Currently, the term "multimodal CT" indicates the combined use of these three techniques in order to obtain a complete picture of the extension of ischemic damage in acute stroke patients.

Acute Disease↗

PubMedDate not supplied

Educational approach on stroke training in Europe.

According to the European Stroke Initiative (EUSI), stroke care is best delivered within a stroke unit by a specialized multidisciplinary stroke team led by stroke specialists. At present, there is no guideline or consensus regarding training requirements or clinical standards that stroke specialists should achieve. It is envisaged that stroke specialists in training would need to acquire adequate knowledge and competency across three major areas of stroke care: acute stroke, stroke rehabilitation, and stroke prevention. With an EUSI document, the European Association of Young Neurologists and Trainees Stroke Subspeciality Group aims to promote discussion on the many aspects of stroke training and the requirements to be a stroke specialist in the European community. The ultimate purpose is to agree on common standards to promote good clinical care and effective stroke prevention across Europe. In the future, this may be translated into better patient outcome and a reduction in the global burden of this condition.

Clinical Competence↗

PubMedDate not supplied

Vascular dementia: the role of cerebral infarcts.

Although vascular dementia (VaD) is the second most frequent cause of dementia after Alzheimer disease (AD), the concept remains controversial in terms of delineation. The objective of this review is to investigate, from available literature, the role of cerebral infarcts in the pathogenesis of VaD and to identify areas of interest that need further evaluation and research. The incidence of new onset dementia is increased after stroke. Stroke subtypes, total volume of cerebral infarction and functional tissue loss, and location of the lesions are probably the major determinants of VaD. Any cause of stroke can lead to VaD. In some circumstances the causal relation between stroke and dementia is clear: (1) in young patients who are unlikely to have associated Alzheimer pathology; (2) when the cognitive functioning was normal before stroke, impaired immediately after, and does not worsen over time; (3) when the lesions are located in strategic areas; and (4) when a well-defined vasculopathy known to cause dementia is proven. However, several issues remain unsolved in VaD: lack of specificity of the diagnostic criteria; influence of white matter changes and associated Alzheimer pathology; influence of preexisting cognitive status; possibility of having VaD without stroke and the clinical relevance of silent infarcts to VaD; and best therapeutic strategy to be used to prevent VaD and to prevent stroke in patients with VaD. These questions form the basis for proposals for future research.

Cerebral Infarction↗

PubMedDate not supplied

Epidemiology of vascular dementia.

Although epidemiological studies are limited by diagnostic uncertainties, they suggest that stroke increases the risk of dementia. The mortality rate is higher in vascular dementia (VaD) than in Alzheimer's disease (AD). Community-based studies have provided several consistent findings: (i) age dependence with prevalence rates doubling every 5 years, (ii) a higher frequency in men and (iii) nation-to-nation differences. The prevalence of VaD ranges from 2.2% in 70- to 79-year-old women, to 16.3% in men >80 years. One sixth of acute stroke patients have preexisting dementia. The incidence of VaD has been studied much less extensively than that of AD, and substantial variations in the incidence rates have been observed: annual incidence rates (per 100,000) range from 20 to 40 between 60 and 69 years of age and from 200 to 700 over 80. The incidence rate of VaD declined over the last 2 decades, probably as a consequence of effective stroke prevention. It is generally assumed that risk factors for VaD are those of stroke, with arterial hypertension as leading factor, followed by atherosclerotic disease, low education level, alcohol abuse and heart disease. Stroke characteristics, such as lacunar infarction and left-sided hemispheric lesions, are major determinants of VaD. The cerebrovascular lesions are likely to be the only cause of dementia in strategic infarcts, in lacunar state, in hereditary cystatin C amyloid angiopathy and in CADASIL. However, white matter changes, and associated Alzheimer pathology, which are both frequent in this age category, may also contribute to the cognitive decline.

Aged↗

PubMedDate not supplied

Multicentre study of l-alpha-glyceryl-phosphorylcholine vs ST200 among patients with probable senile dementia of Alzheimer's type.

A multicentre, randomised, controlled study compared the efficacy of l-alpha-glyceryl-phosphorylcholine (alpha GPC) and ST200 (acetyl-l-carnitine) among 126 patients with probable senile dementia of Alzheimer's type (SDAT) of mild to moderate degree. Efficacy was evaluated by means of behavioural scales and psychometric tests. The results showed significant improvements in most neuropsychological parameters in the alpha GPC recipients. Improvements also occurred in the ST200 recipients but to a lesser extent. Tolerability was good in both groups. These positive findings require replication in larger, double-blind, longitudinal studies coupling clinical and biological determinations.

Acetylcarnitine↗

PubMedDate not supplied

Mental deterioration in old age: results of two multicenter, clinical trials with nimodipine. The Nimodipine Study Group.

The efficacy and tolerability of nimodipine, a calcium antagonist selective for the central nervous system, was evaluated in old age dementias in two multicenter, clinical trials. A total of 755 elderly patients suffering from mental deterioration of degenerative or vascular origin were enrolled in the studies. In the first study, 352 patients received nimodipine 30 mg TID orally for 3 months; in the second study, 403 patients received the same treatment for 6 months. In both studies, psychobehavioral instruments showed a highly significant improvement of the global functional state. In hypertensive patients, nimodipine had a synergistic effect with the antihypertensive drugs. These results confirm the therapeutic efficacy and safety of nimodipine in the treatment of old age dementias.

Activities of Daily Living↗