Micronutrients and Alzheimer's disease

The current high life expectancy is overshadowed by neurodegenerative illnesses that lead to dementia and dependence. Alzheimer's disease (AD) is the most common of these conditions, and is considered to be a proteinopathy, with amyloid-β42 as a key factor, leading via a cascade of events to neurodegeneration. Major factors involved are oxidative stress, perturbed Ca homeostasis and impaired energy metabolism. Protection against oxidative stress by micronutrients (including secondary bioactive substances) has been shown in transgenic Alzheimer model systems to delay AD. Epidemiological evidence is less conclusive, but the vast majority of the evidence supports a protective effect on cognitive functions in old age and AD. Thus, a diet rich in fruits and vegetables but also containing meat and fish is the most suitable to provide adequate micronutrients. The strong link between cardiovascular risk and AD may be explained by common pathogenetic mechanisms mediated, for example, by homocysteine and thus dependant on B-vitamins (folate and vitamins B12 and B6). However, micronutrients may also be harmful. The high affinity of amyloid for metals (Fe, Al and Zn) favours the generation of reactive oxygen species and triggers an inflammatory response. Micronutrients in a balanced diet have a long-lasting, albeit low, protective impact on brain aging, hence prevention should be life lon

The validity of clinical diagnoses of dementia in a group of consecutively autopsied memory clinic patients

Background: Epidemiological studies show that up to 10 % of individuals aged 65 years and older suffer from dementia, most commonly from dementia of the Alzheimer Type (DAT) [1]. Clinicopathological studies are critical to our understanding of this disease and improving the accuracy of clinical diagnoses.Objectives: Our objectives were to examine the validity of clinical diagnoses of DAT, to determine the prevalence of different forms of dementia in this sample, and to investigate the relationship between age at death and polymorbidity.Subjects and method: Clinical data were available from 221 patients who had been examined at the Basel Memory Clinic between 1986 and 1996. From this population, 34 % (75 patients) were autopsied in the Department of Pathology, University Hospital Basel, and neuropathological examinations were additionally performed on 62 (83 %) of these patients. Clinical and neuropathological data were retrospectively compared.Results: 67.8 % of the neuropathologically examined patients received a definitive diagnosis of AD (Alzheimer's disease), vascular dementia (VaD) or mixed dementia (AD and VaD). AD alone or with other histopathological hallmarks of dementia was the most prevalent neuropathological diagnosis (63 %). VaD was deemed the only cause of dementia in only 4.8 % of patients. The sensitivity for DAT was 75.9 %, the specificity 60.6 %. Increasing age was associated with an increasing number of clinical and neuropathological diagnoses.Conclusion: The sensitivity and specificity of the clinical diagnoses of DAT found in our study are similar to previous reports (2-5). Older patients had more etiologies of their dementia than younger patients. This study reaffirms the need for internationally accepted criteria for clinical and neuropathological diagnoses, as well as further clinical-neuropathological investigations to further refine the clinical diagnostic proces

The effects of resistance training on well-being and memory in elderly volunteers

Objective: to determine the short- and long-term effects of resistance training on muscle strength, psychological well-being, control-beliefs, cognitive speed and memory in normally active elderly people. Methods: 46 elderly people (mean age 73.2 years; 18 women and 28 men), were randomly assigned to training and control groups (n = 23 each). Pre- and post-tests were administered 1 week before and 1 week after the 8-week training intervention. The training sessions, performed once a week, consisted of a 10 min warm-up phase and eight resistance exercises on machines. Results: there was a significant increase in maximum dynamic strength in the training group. This training effect was associated with a significant decrease in self-attentiveness, which is known to enhance psychological well-being. No significant changes could be observed in control-beliefs. Modest effects on cognitive functioning occurred with the training procedure: although there were no changes in cognitive speed, significant pre/post-changes could be shown in free recall and recognition in the experimental group. A post-test comparison between the experimental group and control group showed a weak effect for recognition but no significant differences in free recall. Significant long-term effects were found in the training group for muscular strength and memory performance (free recall) 1 year later. Conclusion: an 8-week programme of resistance training lessens anxiety and self-attentiveness and improves muscle strengt

Short-term effect of whole milk and milk fermented by Pseudomonas fluorescens on plasma lipids in adult boars

The short-term effects of whole milk and milk fermented by Pseudomonas fluorescens, of the amino acid composition of the diet and of feeding frequency on the level of plasma lipids, were investigated in six 1-year-old adult boars. The experimental diets contained equal amounts of protein, carbohydrates, fat and cholesterol. After an adaptation period of 5 d for each experimental treatment, blood was collected at regular intervals during 48 h and plasma levels of cholesterol, triacylglycerol, high-density-lipoprotein (HDL)-cholesterol and low-density-lipoprotein (LDL-cholesterol were examined). All variables except HDL-cholesterol showed distinct diurnal fluctuations, which were substantially influenced by feeding frequency. Variations in the amino acid composition of the experimental diets, which were within a physiological range, had no effect on the level of plasma lipids. Plasma lipid levels were significantly lower when the animals received the diets containing milk instead of the diet without milk: cholesterol, triacylglycerol, and LDL-cholesterol were reduced by 5.6, 5.8 and 10% respectively (pondered means) while HDL-cholesterol remained unaffected. Fermentation of whole milk by P. fluorescens reduced the lipid-lowering effect. Our findings suggest that the intake of diets containing milk results in a lower plasma cholesterol and LDL-cholesterol level than the intake of diets with a similar nutrient content which do not contain mil

Artificial Neural Network to predict mean monthly total ozone in Arosa, Switzerland

Present study deals with the mean monthly total ozone time series over Arosa, Switzerland. The study period is 1932-1971. First of all, the total ozone time series has been identified as a complex system and then Artificial Neural Networks models in the form of Multilayer Perceptron with back propagation learning have been developed. The models are Single-hidden-layer and Two-hidden-layer Perceptrons with sigmoid activation function. After sequential learning with learning rate 0.9 the peak total ozone period (February-May) concentrations of mean monthly total ozone have been predicted by the two neural net models. After training and validation, both of the models are found skillful. But, Two-hidden-layer Perceptron is found to be more adroit in predicting the mean monthly total ozone concentrations over the aforesaid period.Comment: 22 pages, 14 figure

Humoral response to mRNA vaccines against SARS-CoV-2 in patients with humoral immunodeficiency disease.

OBJECTIVES Although mRNA-based vaccines against SARS-CoV-2 induce a robust immune response and prevent infections and hospitalizations, there are limited data on the antibody response in individuals with humoral immunodeficiency. The aim of this study was to evaluate the humoral immune response after two vaccine doses with BNT162b2 or mRNA-1273 in patients with humoral immunodeficiency disease. METHODS This cross-sectional study assessed 39 individuals with hypogammaglobulinemia under immunoglobulin replacement therapy. IgG anti-SARS-CoV-2 spike protein antibodies (anti-S) were measured 4 weeks to 4 months after two doses of an mRNA vaccine against SARS-CoV-2. The proportion of patients, who developed a humoral immune response to the spike protein were evaluated and compared to 19 healthy controls. RESULTS After vaccination with two vaccine doses, 26/39 patients (66.7%) with humoral immunodeficiency disease and all healthy controls developed anti-S. In subjects with baseline IgG 5 g/l: 151.5 AU/ml (95%CI 109.0-400.0), healthy controls 250.0 AU/ml (95%CI 209.0-358.0), p = 0.007. CONCLUSION In most patients with mild to moderate humoral immunodeficiency we found only slightly lower anti-S antibodies compared with healthy controls after two vaccine doses with BNT162b2 and mRNA-1273. However, in patients with a decreased baseline IgG below 3 g/l and/or under immunosuppressive drugs, we found severely impaired humoral immune responses