Ageing is a complex phenomenon affecting a wide range of coexisting biological processes. The homogeneity of the studied population is an essential parameter for valid interpretations of outcomes. The presented study capitalises on the MRI data available in the Human Connectome Project-Aging (HCP-A) and, within individuals over 55 years of age who passed the HCP-A section criteria, compares a subgroup of 37 apparently neurocognitively healthy individuals selected based on stringent criteria with 37 age and sex-matched individuals still representative of typical ageing but who did not pass the stringent definition of neurocognitively healthy. Specifically, structural scans, diffusion weighted imaging and T1w/T2w ratio were utilised. Furthermore, data of 26 HCP-A participants older than 90 years as notional 'super-agers' were analysed. The relationship of age and several microstructural MRI metrics (T1w/T2w ratio, mean diffusivity, intracellular volume fraction and free water volume fraction) differed significantly between typical and healthy ageing cohort in areas highly relevant for ageing such as hippocampus, prefrontal and temporal cortex and cerebellum. However, the trajectories of the healthy ageing population did not show substantially better overlap with the findings in people older than 90 than those of the typical population. Therefore, caution must be exercised in the choice of adequate study group characteristics relevant for respective ageing-related hypotheses. Contrary to typical ageing group, the healthy ageing cohort may show generally stable levels of several MRI metrics of interest.
- MeSH
- kognice * fyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mozek diagnostické zobrazování MeSH
- šedá hmota * diagnostické zobrazování MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- stárnutí * fyziologie MeSH
- zdravé stárnutí fyziologie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Dysfagie neboli porucha polykání je častým problémem u stárnoucí populace, přičemž její výskyt narůstá s věkem. Fyziologická ztráta motorických a senzitivních funkcí vede k presbyfagii, což je nepravá dysfagie u zdravých jedinců. Skutečná dysfagie vzniká při komplikacích způsobených akutním onemocněním. Incidence dysfagie je vysoká, v USA se udává, že 6–7 % osob trpí touto poruchou. U seniorů nad 65 let je aspirační bronchopneumonie, často způsobená dysfagií, čtvrtou nejčastější příčinou úmrtí. Po cévní mozkové příhodě (CMP) se dysfagie vyskytuje u 37–38 % pacientů a u neurodegenerativních onemocnění, jako je demence, až u 93 % pacientů. Dysfagie ve stáří ovlivňuje všechny fáze polykání: orální přípravnou, orální transportní, faryngeální a ezofageální. Diagnostika vyžaduje spolupráci specialistů a zahrnuje metody jako FEES a VFSS. Terapie se zaměřuje na udržení bezpečného příjmu potravy a zahrnuje logopedickou intervenci, cvičení a manévry na zlepšení svalové síly a koordinace. Kompenzační techniky a rehabilitační postupy jsou klíčové pro prevenci komplikací. Presbyfagie je často opomíjená, a proto je důležitá mezioborová spolupráce a edukace rodinných příslušníků pro zajištění adekvátní péče. Korespondenční adresa: MUDr. Jana Šatanková, Ph.D. Klinika otorinolaryngologie a chirurgie hlavy a krku LF UK a FN Sokolská 581, 500 05 Hradec Králové e-mail: jana.satankova@fnhk.cz
Dysphagia, or swallowing disorder, is a common problem in the aging population, with its incidence increasing with age. The physiological loss of motor and sensory functions leads to presbyphagia, which is a false dysphagia in healthy individuals. True dysphagia occurs with complications caused by acute illness. The incidence of dysphagia is high, with 6-7% of people in the USA reported to suffer from this disorder. In the elderly over 65, aspiration bronchopneumonia, often caused by dysphagia, is the fourth most common cause of death. After a stroke, dysphagia occurs in 37-38% of patients and in neurodegenerative diseases such as dementia in up to 93% of patients. Dysphagia in old age affects all phases of swallowing: oral preparatory, oral transport, pharyngeal and oesophageal. Diagnosis requires the collaboration of specialists and includes methods such as FEES and VFSS. Therapy focuses on maintaining safe eating and includes speech therapy intervention, exercises and manoeuvres to improve muscle strength and coordination. Compensatory techniques and rehabilitation procedures are key to preventing complications. Presbyphagia is often neglected, so interdisciplinary collaboration and education of family members is important to ensure adequate care.
- MeSH
- endosonografie metody MeSH
- fluoroskopie metody MeSH
- lidé MeSH
- polykání fyziologie MeSH
- poruchy polykání * diagnóza etiologie patofyziologie terapie MeSH
- rehabilitace metody MeSH
- senioři MeSH
- stárnutí * fyziologie MeSH
- Check Tag
- lidé MeSH
- senioři MeSH
- Publikační typ
- přehledy MeSH
Various studies have correlated the mechanical properties of the aortic wall with its biochemical parameters and inner structure. Very few studies have addressed correlations with the cohesive properties, which are crucial for understanding fracture phenomena such as aortic dissection, i.e. a life-threatening process. Aimed at filling this gap, we conducted a comprehensive biochemical and histological analysis of human aortas (the ascending and descending thoracic and infrarenal abdominal aorta) from 34 cadavers obtained post-mortem during regular autopsies. The pentosidine, hydroxyproline and calcium contents, calcium/phosphorus molar ratio, degree of atherosclerosis, area fraction of elastin, collagen type I and III, alpha smooth muscle actin, vasa vasorum, vasa vasorum density, aortic wall thickness, thicknesses of the adventitia, media and intima were determined and correlated with the delamination forces in the longitudinal and circumferential directions of the vessel as determined from identical cadavers. The majority of the parameters determined did not indicate significant correlation with age, except for the calcium content and collagen maturation (enzymatic crosslinking). The main results concern differences between enzymatic and non-enzymatic crosslinking and those caused by the presence of atherosclerosis. The enzymatic crosslinking of collagen increased with age and was accompanied by a decrease in the delamination strength, while non-enzymatic crosslinking tended to decrease with age and was accompanied by an increase in the delamination strength. As the rate of calcification increased, the presence of atherosclerosis led to the formation of calcium phosphate plaques with higher solubility than the tissue without or with only mild signs of atherosclerosis. STATEMENT OF SIGNIFICANCE: This study presents a detailed biochemical and histological analysis of human aortic samples (ascending thoracic aorta, descending thoracic aorta and infrarenal abdominal aorta) taken from 34 cadavers. The contribution of this scientific study lies in the detailed biochemical comparison of the enzymatic and non-enzymatic glycosylation-derived crosslinks of vascular tissues and their influence on the delamination strength of the human aorta since, to the best of our knowledge, no such comprehensive studies exist in the literature. A further benefit concerns the notification of the limitations of the various analytical methods applied; an important factor that must be taken into account in such studies.
- MeSH
- aktiny metabolismus MeSH
- aorta * metabolismus MeSH
- arginin analogy a deriváty MeSH
- ateroskleróza metabolismus patologie MeSH
- dospělí MeSH
- elastin metabolismus MeSH
- hydroxyprolin metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- lysin analogy a deriváty metabolismus MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- stárnutí * fyziologie MeSH
- vápník metabolismus MeSH
- vasa vasorum metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Age-related brain changes affect sleep and are reflected in properties of sleep slow-waves, however, the precise mechanisms behind these changes are still not completely understood. Here, we adapt a previously established whole-brain model relating structural connectivity changes to resting state dynamics, and extend it to a slow-wave sleep brain state. In particular, starting from a representative connectome at the beginning of the aging trajectory, we have gradually reduced the inter-hemispheric connections, and simulated sleep-like slow-wave activity. We show that the main empirically observed trends, namely a decrease in duration and increase in variability of the slow waves are captured by the model. Furthermore, comparing the simulated EEG activity to the source signals, we suggest that the empirically observed decrease in amplitude of the slow waves is caused by the decrease in synchrony between brain regions.
- MeSH
- dospělí MeSH
- elektroencefalografie * MeSH
- konektom * MeSH
- lidé středního věku MeSH
- lidé MeSH
- modely neurologické * MeSH
- mozek * fyziologie MeSH
- počítačová simulace MeSH
- senioři MeSH
- spánek pomalých vln * fyziologie MeSH
- stárnutí * fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND AND OBJECTIVES: Disentangling brain aging from disease-related neurodegeneration in patients with multiple sclerosis (PwMS) is increasingly topical. The brain-age paradigm offers a window into this problem but may miss disease-specific effects. In this study, we investigated whether a disease-specific model might complement the brain-age gap (BAG) by capturing aspects unique to MS. METHODS: In this retrospective study, we collected 3D T1-weighted brain MRI scans of PwMS to build (1) a cross-sectional multicentric cohort for age and disease duration (DD) modeling and (2) a longitudinal single-center cohort of patients with early MS as a clinical use case. We trained and evaluated a 3D DenseNet architecture to predict DD from minimally preprocessed images while age predictions were obtained with the DeepBrainNet model. The brain-predicted DD gap (the difference between predicted and actual duration) was proposed as a DD-adjusted global measure of MS-specific brain damage. Model predictions were scrutinized to assess the influence of lesions and brain volumes while the DD gap was biologically and clinically validated within a linear model framework assessing its relationship with BAG and physical disability measured with the Expanded Disability Status Scale (EDSS). RESULTS: We gathered MRI scans of 4,392 PwMS (69.7% female, age: 42.8 ± 10.6 years, DD: 11.4 ± 9.3 years) from 15 centers while the early MS cohort included 749 sessions from 252 patients (64.7% female, age: 34.5 ± 8.3 years, DD: 0.7 ± 1.2 years). Our model predicted DD better than chance (mean absolute error = 5.63 years, R2 = 0.34) and was nearly orthogonal to the brain-age model (correlation between DD and BAGs: r = 0.06 [0.00-0.13], p = 0.07). Predictions were influenced by distributed variations in brain volume and, unlike brain-predicted age, were sensitive to MS lesions (difference between unfilled and filled scans: 0.55 years [0.51-0.59], p < 0.001). DD gap significantly explained EDSS changes (B = 0.060 [0.038-0.082], p < 0.001), adding to BAG (ΔR2 = 0.012, p < 0.001). Longitudinally, increasing DD gap was associated with greater annualized EDSS change (r = 0.50 [0.39-0.60], p < 0.001), with an incremental contribution in explaining disability worsening compared with changes in BAG alone (ΔR2 = 0.064, p < 0.001). DISCUSSION: The brain-predicted DD gap is sensitive to MS-related lesions and brain atrophy, adds to the brain-age paradigm in explaining physical disability both cross-sectionally and longitudinally, and may be used as an MS-specific biomarker of disease severity and progression.
- MeSH
- deep learning * MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- longitudinální studie MeSH
- magnetická rezonanční tomografie * MeSH
- mozek * diagnostické zobrazování patologie MeSH
- neurodegenerativní nemoci diagnostické zobrazování MeSH
- průřezové studie MeSH
- retrospektivní studie MeSH
- roztroušená skleróza * diagnostické zobrazování patologie MeSH
- stárnutí * patologie fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- MeSH
- alveolární makrofágy fyziologie klasifikace MeSH
- dýchací soustava patofyziologie MeSH
- infekce dýchací soustavy * klasifikace patofyziologie patologie MeSH
- lidé MeSH
- mikrobiota MeSH
- plicní nemoci klasifikace patologie MeSH
- pneumonie klasifikace patologie MeSH
- stárnutí fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
The relationship between working memory (WM) and neuronal oscillations can be studied in detail using brain stimulation techniques, which provide a method for modulating these oscillations and thus influencing WM. The endogenous coupling between the amplitude of gamma oscillations and the phase of theta oscillations is crucial for cognitive control. Theta/gamma peak-coupled transcranial alternating current stimulation (TGCp-tACS) can modulate this coupling and thus influence WM performance. This study investigated the effects of TGCp-tACS on WM in older adults and compared their responses with those of younger participants from our previous work who underwent the same experimental design. Twenty-eight older subjects underwent both TGCp-tACS and sham stimulation sessions at least 72 h apart. Resting-state electroencephalography (EEG) was recorded before and after the interventions, and a WM task battery with five different WM tasks was performed during the interventions to assess various WM components. Outcomes measured included WM task performance (e.g., accuracy, reaction time (RT)) and changes in power spectral density (PSD) in different frequency bands. TGCp-tACS significantly decreased accuracy and RT on the 10- and 14-point Sternberg tasks and increased RT on the Digit Symbol Substitution Test in older adults. In contrast, younger participants showed a significant increase in accuracy only on the 14-item Sternberg task. Electrophysiological analysis revealed a decrease in delta and theta PSD and an increase in high gamma PSD in both younger and older participants after verum stimulation. In conclusion, theta-gamma coupling is essential for WM and modulation of this coupling affects WM performance. The effects of TGCp-tACS on WM vary with age due to natural brain changes. To better support older adults, the study suggests several strategies to improve cognitive function, including: Adjusting stimulation parameters, applying stimulation to two sites, conducting multiple sessions, and using brain imaging techniques for precise targeting.
- MeSH
- dospělí MeSH
- elektroencefalografie MeSH
- gama rytmus EEG * fyziologie MeSH
- krátkodobá paměť * fyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- přímá transkraniální stimulace mozku * MeSH
- reakční čas fyziologie MeSH
- senioři MeSH
- stárnutí fyziologie MeSH
- theta rytmus EEG * fyziologie MeSH
- zdraví MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
White matter (WM) development has been studied extensively, but most studies used cross-sectional data, and to the best of our knowledge, none of them considered the possible effects of biological (vs. chronological) age. Therefore, we conducted a longitudinal multimodal study of WM development and studied changes in fractional anisotropy (FA) in the different WM tracts and their relationship with cortical thickness-based measures of brain aging in young adulthood. A total of 105 participants from the European Longitudinal Study of Pregnancy and Childhood (ELSPAC) prenatal birth cohort underwent magnetic resonance imaging (MRI) at the age of 23-24, and the age of 28-30 years. At both time points, FA in the different WM tracts was extracted using the JHU atlas, and brain age gap estimate (BrainAGE) was calculated using the Neuroanatomical Age Prediction using R (NAPR) model based on cortical thickness maps. Changes in FA and the speed of cortical brain aging were calculated as the difference between the respective variables in the late vs. early 20s. We demonstrated tract-specific increases as well as decreases in FA, which indicate that the WM microstructure continues to develop in the third decade of life. Moreover, the significant interaction between the speed of cortical brain aging, tract, and sex on mean FA revealed that a greater speed of cortical brain aging in young adulthood predicted greater decreases in FA in the bilateral cingulum and left superior longitudinal fasciculus in young adult men. Overall, these changes in FA in the WM tracts in young adulthood point out the protracted development of WM microstructure, particularly in men.
- MeSH
- anizotropie MeSH
- bílá hmota * diagnostické zobrazování růst a vývoj MeSH
- dospělí MeSH
- lidé MeSH
- longitudinální studie MeSH
- mladý dospělý MeSH
- mozek * růst a vývoj diagnostické zobrazování anatomie a histologie MeSH
- stárnutí * fyziologie MeSH
- zobrazování difuzních tenzorů metody MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Aortic dissection is a life-threatening disease that consists in the development of a tear in the wall of the aorta. The initial tear propagates as a discontinuity leading to separation within the aortic wall, which can result in the creation of a so-called false lumen. A fatal threat occurs if the rupture extends through the whole thickness of the aortic wall, as blood may then leak. It is generally accepted that the dissection, which can sometime extend along the entire length of the aorta, propagates via a delamination mechanism. The aim of the present paper is to provide experimentally validated parameters of a mathematical model for the description of the wall's cohesion. A model of the peeling experiment was built in Abaqus. The delamination interface was described by a piecewise linear traction-separation law. The bulk behavior of the aorta was assumed to be nonlinearly elastic, anisotropic, and incompressible. Our simulations resulted in estimates of the material parameters for the traction-separation law of the human descending thoracic aorta, which were obtained by minimizing the differences between the FEM predictions and the delamination force given by the regression of the peeling experiments. The results show that the stress at damage initiation, Tc, should be understood as an age-dependent quantity, and under the assumptions of our model this dependence can be expressed by linear regression as Tc = - 13.03·10-4·Age + 0.2485 if the crack front advances in the axial direction, and Tc = - 7.58·10-4·Age + 0.1897 if the crack front advances in the direction of the aortic circumference (Tc [MPa], Age [years]). Other model parameters were the stiffness K and the separation at failure, δf-δc (K = 0.5 MPa/mm, δf-δc = 0.1 mm). The material parameters provided by our study can be used in numerical simulations of the biomechanics of dissection propagation through the aorta especially when age-associated phenomena are studied.
- MeSH
- analýza metodou konečných prvků MeSH
- aorta thoracica * fyziologie MeSH
- biomechanika MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mechanický stres MeSH
- modely kardiovaskulární MeSH
- počítačová simulace MeSH
- senioři MeSH
- stárnutí fyziologie MeSH
- trakce MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
