Search results for "ECL"

Screening of pharmacologic adulterant classes in herbal formulations using voltammetry of microparticles.

2013

A solid state electrochemical method for screening different families of adulterant chemicals illegally added to commercial phytotherapuetic formulations is described. The proposed method, based on the voltammetry of microparticles approach, permits a fast and sensitive way to distinguish between anorexics (amfepramone, fenproporex, sibutramine), benzozodiazepinic anxiolytics (clonazepam, flurazepam, alprazolam, midazolam, medazepam, chlordiazepoxide, diazepam), antidepressants (bupropione, fluoxetine, sertraline, paroxetine), diuretics (hydrochlorothiazide, furosemide, chlortalidone, amiloride, spironolactone), and hypoglycemics (glimepiride, chlorpropamide, glibenclamide) based on charact…

Acute psychosocial stress effects on memory performance: Relevance of age and sex.

2018

In recent decades, there has been a growing interest in investigating the effects of chronic and acute stress on cognitive processes, especially memory performance. However, research focusing on acute stress effects has reported contradictory findings, probably due to the many factors that can moderate this relationship. In addition to factors related to the individual, such as sex and age, other factors, such as the type of memory assessed, can play a critical role in the direction of these effects. This review summarizes the main findings of our research group and others about the effects of acute psychosocial stress on memory performance in young and older people of both sexes, taking in…

Longitudinal Study on Sustained Attention to Response Task (SART): Clustering Approach for Mobility and Cognitive Decline

2022

The Sustained Attention to Response Task (SART) is a computer-based go/no-go task to measure neurocognitive function in older adults. However, simplified average features of this complex dataset lead to loss of primary information and fail to express associations between test performance and clinically meaningful outcomes. Here, we combine a novel method to visualise individual trial (raw) information obtained from the SART test in a large population-based study of ageing in Ireland and an automatic clustering technique. We employed a thresholding method, based on the individual trial number of mistakes, to identify poorer SART performances and a fuzzy clusters algorithm to partition the da…

EFFETTO DEGLI ESTRATTI DI PAPAYA FERMENTATA SULLO STRESS OSSIDATIVO IN PAZIENTI CON MALATTIA DI ALZHEIMER

2013

Brain tissue is particularly susceptible to oxidative damage, which has been associated with pathological findings of Alzheimer's disease (AD), such as amyloid plaques and protein fibrils. Oxidative stress alterations, including increased production of reactive oxygen metabolites, decline of antioxidant systems, and decreased efficiency in repairing molecules, have been linked to the development of AD. Postmortem studies on brain tissue from AD patients have shown several oxidative damage markers, such as increased lipid peroxidation, oxidative damage of proteins, glyco-oxidation, and reduction of antioxidant systems. We studied 40 patients referred to our Geriatric Unit (age 78,2 ± 1,1 yea…

Pharmacological heterogeneity of γ-aminobutyric acid receptors during development suggests distinct classes of rat cerebellar granule cells in situ

2001

The gamma-aminobutyric acid receptor (GABA(A)R) represents a ligand-gated Cl(-)-channel assembling as heteropentamere from 19 known subunits. Cerebellar granule cells contain a unique subset, namely the alpha1-, alpha6-, beta2-, gamma2- and delta-subunits. We studied their GABAergic pharmacology in situ using whole-cell patch-clamp recordings in brain slices and a modified Y-tube application system. The distribution of the EC50s for GABA in young (P8-P14) and medium aged animals (P15-P28) could be fitted with the sum of two Gaussian distributions with means of 60 and 185 microM and 27 and 214 microM, respectively. In older animals (P29-P48) the observed homogeneous range of sensitivities fi…

Awareness of Cognitive Decline in Patients With Alzheimer's Disease: A Systematic Review and Meta-Analysis

2021

Background: Identifying a poor degree of awareness of cognitive decline (ACD) could represent an early indicator of Alzheimer's disease (AD).Objectives: (1) to understand whether there is evidence of poor ACD in the pre-dementia stages of AD; (2) to summarize the main findings obtained investigating ACD in AD; (3) to propose a conceptual framework.Data Sources: We searched Scopus, Pubmed, and the reference lists for studies published up to August 2020. Original research articles must report a measure of ACD and included individuals with AD dementia, or prodromal AD (or MCI), or being at risk for AD.Data Synthesis: All studies covering preclinical, prodromal, and AD dementia were systematica…

Microvascular brain damage with aging and hypertension

2011

Loss of cognitive function and hypertension are two common conditions in the elderly and both significantly contribute to loss of personal independency. Microvascular brain damage - the result of age-associated alteration in large arteries and the progressive mismatch of their cross-talk with small cerebral arteries - represents a potent risk factor for cognitive decline and for the onset of dementia in older individuals. The present review discusses the complexity of factors linking large artery to microvascular brain disease and to cognitive decline and the evidence for possible clinical markers useful for prevention of this phenomenon. The possibility of dementia prevention by cardiovasc…

2021

Introduction: Functional imaging studies have demonstrated the recruitment of additional neural resources as a possible mechanism to compensate for age and Alzheimer’s disease (AD)-related cerebral pathology, the efficacy of which is potentially modulated by underlying structural network connectivity. Additionally, structural network efficiency (SNE) is associated with intelligence across the lifespan, which is a known factor for resilience to cognitive decline. We hypothesized that SNE may be a surrogate of the physiological basis of resilience to cognitive decline in elderly persons without dementia and with age- and AD-related cerebral pathology.Methods: We included 85 cognitively normal…

Postprandial Hyperglycemia Is Associated With White Matter Hyperintensity and Brain Atrophy in Older Patients With Type 2 Diabetes Mellitus

2018

Type 2 diabetes mellitus is associated with neurodegeneration and cerebrovascular disease. However, the precise mechanism underlying the effects of glucose management on brain abnormalities is not fully understood. The differential impacts of glucose alteration on brain changes in patients with and without cognitive impairment are also unclear. This cross-sectional study included 57 older type 2 diabetes patients with a diagnosis of Alzheimer's disease (AD) or normal cognition (NC). We examined the effects of hypoglycemia, postprandial hyperglycemia and glucose fluctuations on regional white matter hyperintensity (WMH) and brain atrophy among these patients. In a multiple regression analysi…

A low cortisol response to acute stress is related to worse basal memory performance in older people

2014

Age-related memory decline has been associated with a faulty regulation of the hypothalamus-pituitary-adrenal axis (HPA-axis). The aim of this study was to investigate whether the magnitude of the stress-induced cortisol increase is related to memory performance when memory is measured in non-stressful conditions. To do so, declarative and working memory performance were measured in 31 men and 35 women between 55 and 77 years of age. On a different day, the magnitude of their cortisol response to acute psychosocial stress was measured. The relationship between the cortisol response and memory performance was U shaped: a low cortisol response to stress was related to poorer declarative and w…