• MeSH
• Neurophysiology MeSH
• Ocular Physiological Phenomena MeSH
• Vision, Ocular physiology   MeSH
• Publication type
• Congress MeSH

• Conspectus
• Lékařské vědy. Lékařství
• NML Fields
• fyziologie
• neurovědy
• oftalmologie

• MeSH
• Behavior MeSH
• Molecular Biology MeSH
• Nervous System Diseases MeSH
• Nervous System MeSH
• Neurochemistry MeSH
• Neurophysiology MeSH
• Neurons MeSH
• Neurosciences MeSH
• Publication type
• Monograph MeSH

• Conspectus
• Fyziologie člověka a srovnávací fyziologie
• NML Fields
• neurovědy
• biologie

INTRODUCTION: Studies in the sensorimotor system of older versus young individuals have shown alterations in functional connectivity and organization. Our objective was to explore the implications of these differences in terms of local organizations, and to identify processes that correlate with neuropsychological parameters. METHODS: Using a novel multivariate analysis method on resting-state functional MRI data obtained from 50 young and 31 older healthy individuals, we identified directed 4-node functional pathways within the sensorimotor system and examined their correlations with neuropsychological assessments. RESULTS: In young individuals, the functional pathways were unidirectional, flowing from the primary motor and sensory cortices to higher motor and visual regions. In older individuals, the functional pathways were more complex. They originated either from the calcarine sulcus or the insula and passed through mutually coupled high-order motor areas before reaching the primary sensory and motor cortices. Additionally, the pathways in older individuals that resembled those found in young individuals exhibited a positive correlation with years of education. DISCUSSION: The flow pattern of young individuals suggests efficient and fast information transfer. In contrast, the mutual coupling of high-order motor regions in older individuals suggests an inefficient and slow transfer, a less segregated and a more integrated organization. The differences in the number of sensorimotor pathways and of their directionality suggests reduced efferent degenerated pathways and increased afferent compensated pathways. Furthermore, the positive effect of years of education may be associated with the Cognitive Reserve Hypothesis, implying that cognitive reserve could be maintained through specific information transfer pathways.

• Publication type
• Journal Article MeSH

• MeSH
• Cell Biology MeSH
• Molecular Biology MeSH
• Publication type
• Monograph MeSH

• Conspectus
• Biochemie. Molekulární biologie. Biofyzika
• NML Fields
• biologie
• cytologie, klinická cytologie

Ortokeratologické čočky představují speciální typ pevné kontaktní čočky, který se používá pro korekci zejména myopie. Čočky se nosí v noci, kdy díky specifickému tvaru způsobí dočasnou (reverzibilní) změnu topografie povrchu rohovky. Přes den pak není nutné nosit jakoukoli jinou korekci. Vzhledem k režimu nošení je oproti klasickým kontaktním čočkám zvýšené riziko zdravotních komplikací. Pro jejich bezpečné používání je proto nutné dbát na aplikaci čoček s vhodnými parametry, dodržení postupu péče a hygieny, pravidelných kontrol a včasného řešení případných problémů. Aplikovat je může jen zkušený a dobře vyškolený kontaktolog. V ČR tato metoda není téměř používána. Cílem prezentované případové studie bylo sledovat průběh konkrétní aplikace ortokeratologických čoček pro korekci myopie z optického (refrakčního) hlediska a optické změny v systému oka vyhodnotit. U sledovaného subjektu byly měřeny změny subjektivní refrakce, vízu, poloměru zakřivení rohovky, rohovkových a celkových očních aberací a tloušťky rohovky po dobu jednoho měsíce od začátku používání čoček (první fáze). Stejné parametry byly sledovány po dobu jednoho měsíce od ukončení nošení čoček po předchozím tříměsíčním nošení (druhá fáze). Subjekt byla žena, 24 let, myopka, OD sféra -3,00 D, cylindr -0,25 D s osou 90°, OS sféra -2,75 D, bez očních nebo celkových onemocnění. K plné korekci refrakční vady vlivem aplikace ortokeratologických čoček došlo přibližně po čtyřech nocích (přespáních) s čočkami. Přitom během dne byl patrný mírný návrat k původním hodnotám. S poklesem refrakce se odpovídajícím způsobem zlepšoval nekorigovaný vízus. Dále bylo pozorováno centrální oploštění rohovky, tj. nárůst centrálního poloměru zakřivení (maximální změna byla 0,22 mm pro pravé a 0,28 mm pro levé oko) a mírné ztenčení. Nežádoucím optickým doprovodným jevem bylo navýšení aberací vyšších řádů, který se subjektivně projevil zhoršeným viděním za šera. Měsíc po ukončení aplikace se všechny sledované parametry vrátily do původních hodnot.

Introduction: Orthokeratology lenses present a special type of hard contact lenses, which is used especially for myopic correction. The lenses are applied during the night, when thanks to their special shape cause temporally (reversible) change of the cornea shape. During the day, there is not necessary to wear any other refractive correction. Due to the wearing regimen, there is, comparing to the classical contact lenses, higher risk of health complications. For their safe use, it is necessary to pay attention to the application of lenses of adequate parameters, follow up the care and hygiene precautions, regular controls and early treatment of possible problems. The application of contact lenses should be done by experienced and well-educated expert in contact lens fitting. In the Czech Republic, this method is practically not used. Aim: The aim of the case report was to follow up the course of concrete application of orthokeratology lenses for myopic correction from the optic (refractive) point of view, and to evaluate the optic changes in the system of the eye. In the followed up subject, there were measured subjective changes in refraction, visual acuity, corneal curvature, corneal and whole eye aberrations, and corneal thickness during the period of one month after the beginning of lens application (initial phase). The same parameters were followed-up during one-month period since the termination of lens wearing for three months (second phase). The subject was a woman, 24 years old, myopic, with the refractive error in the right eye –3.0 spherical diopters and astigmatism of –0.25 cylinder in the axis 90°, and in the left eye –2.75 spherical diopters without astigmatism; without ophthalmologic or systemic diseases. The full correction of the refractive error after the orthokeratology lenses application occurred approximately after four nights (wearing the lenses overnight). Concurrently, during the day, slight recurrence to original values was evident. With the decreased refractive error, the uncorrected visual acuity improved accordingly. Further, the flattening of the central cornea was observed, e.g. increasing of the central cornea curvature diameter (maximum change was 0.22 mm in the right and 0.28 mm in the left eye) and slight thinning. The adverse accompanying optic phenomenon was increasing of the aberrations of higher orders, which presented subjectively by decreased visual acuity under mesopic conditions. One month after the termination of contact lenses wearing, all the followed-up parameters returned to original values.

• Keywords
• ortokeratologické kontaktní čočky,
• MeSH
• Contact Lenses * MeSH
• Humans MeSH
• Young Adult MeSH
• Myopia * therapy   MeSH
• Ocular Physiological Phenomena MeSH
• Eye physiopathology   MeSH
• Treatment Outcome MeSH
• Check Tag
• Humans MeSH
• Young Adult MeSH
• Female MeSH
• Publication type
• Case Reports MeSH

• MeSH
• Cells * MeSH
• Molecular Biology MeSH

• Conspectus
• Biochemie. Molekulární biologie. Biofyzika
• NML Fields
• molekulární biologie, molekulární medicína
• NML Publication type
• učebnice vysokých škol

• MeSH
• Brain MeSH
• Neurophysiology MeSH
• Neurons MeSH

• Conspectus
• Patologie. Klinická medicína
• NML Fields
• neurologie
• neurovědy

Bilingualism (BL) is increasing around the world. Although BL has been shown to have a broad impact-both positive and negative-on language and cognitive functioning, cognitive models and standards are mainly based on monolinguals. If we take cognitive performance of monolinguals as a standard, then the performance of bilinguals might not be accurately estimated. The assessment of cognitive functions is an important part of both the diagnostic process and further treatment in neurological and neuropsychiatric patients. In order to identify the presence or absence of cognitive deficit in bilingual patients, it will be important to determine the positive and/or negative impact of BL properties on measured cognitive performance. However, research of the impact of BL on cognitive performance in neuropsychiatric patients is limited. This article aims to compare the influence of the language (dominant-L1, second-L2) used for assessment of verbal cognitive performance in two cases of bilingual neuropsychiatric patients (English/Czech). Despite the fact that the two cases have different diagnoses, similarities in working memory and verbal learning profiles for L1 and L2 were present in both patients. We expected L1 to have higher performance in all measures when compared with L2. This assumption was partially confirmed. As expected, verbal working memory performance was better when assessed in L1. In contrast, verbal learning showed the same or better performance in L2 when compared with L1. Verbal fluency and immediate recall results were comparable in both languages. In conclusion, the language of administration partially influenced verbal performance of bilingual patients. Whether the language itself influenced low performance in a given language or it was a result of a deficit requires further research. According to our results, we suggest that an assessment in both languages needs to be a component of reasonable cognitive assessment of bilingual patients.

• MeSH
• Adult MeSH
• Mental Disorders diagnosis   MeSH
• Cognition * MeSH
• Memory, Short-Term * MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Multilingualism * MeSH
• Neuropsychological Tests MeSH
• Verbal Learning * MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH
• Research Support, Non-U.S. Gov't MeSH

M systems are mathematical models of morphogenesis developed to gain insights into its relations to phenomena such as self-assembly, self-controlled growth, homeostasis, self-healing and self-reproduction, in both natural and artificial systems. M systems rely on basic principles of membrane computing and self-assembly, as well as explicit emphasis on geometrical structures (location and shape) in 2D, 3D or higher dimensional Euclidean spaces. They can be used for principled studies of these phenomena, both theoretically and experimentally, at a computational level abstracted from their detailed implementation. In particular, they afford 2D and 3D models to explore biological morphogenetic processes. Theoretical studies have shown that M systems are powerful tools (e.g., computational universal, i.e. can become as complex as any computer program) and their parallelism allows for trading space for time in solving efficiently problems considered infeasible on conventional computers (NP-hard problems). In addition, they can also exhibit properties such as robustness to injuries and degrees of self-healing. This paper focuses on the experimental side of M systems. To this end, we have developed a high-level morphogenetic simulator, Cytos, to implement and visualize M systems in silico in order to verify theoretical results and facilitate research in M systems. We summarize the software package and make a brief comparison with some other simulators of membrane systems. The core of the article is a description of a range of experiments inspired by aspects of morphogenesis in both prokaryotic and eukaryotic cells. The experiments explore the regulatory role of the septum and of the cytoskeleton in cell fission, the robustness of cell models against injuries, and, finally, the impact of changing nutrient concentration on population growth.

• MeSH
• Algorithms * MeSH
• Cell Division MeSH
• Cytoskeleton metabolism   MeSH
• Eukaryotic Cells cytology   metabolism   MeSH
• Morphogenesis * MeSH
• Computer Simulation MeSH
• Prokaryotic Cells cytology   metabolism   MeSH
• Software * MeSH
• Models, Theoretical * MeSH
• Computational Biology methods   MeSH
• Publication type
• Journal Article MeSH

The utilization of artificial snow for environmentally relevant (photo)chemical studies was systematically investigated. Contaminated snow samples were prepared by various methods: by shock freezing of the aqueous solutions sprayed into liquid nitrogen or inside a large walk-in cold chamber at -35 °C, or by adsorption of gaseous contaminants on the surface of artificially prepared pure or natural urban snow. The specific surface area of artificial snow grains produced in liquid nitrogen was determined using valerophenone photochemistry (400-440 cm(2) g(-1)) to estimate the surface coverage by small hydrophobic organic contaminants. The dynamics of recombination/dissociation (cage effect) of benzyl radical pairs, photochemically produced from 4-methyldibenzyl ketone on the snow surface, was investigated. The initial ketone loading, c = 10(-6)-10(-8) mol kg(-1), only about 1-2 orders of magnitude higher than the contaminant concentrations commonly found in nature, was already well below monolayer coverage. We found that the efficiency of out-of-cage reactions decreased at much higher temperatures than those previously determined for frozen solutions; however, the cage effect was essentially the same no matter what technique of snow production or ketone deposition/uptake was used, including the experiments with collected natural snow. The experimental observation that the contaminant molecules are initially self-associated even at the lowest concentrations was supported by DFT calculations. We conclude that, contrary to frozen aqueous solutions, in which the impurities reside in a 3D cage (micropocket), contaminant molecules located on the artificial snow grain surface at low concentrations can be visualized in terms of a 2D cage. Artificial snow thus represents a readily available study matrix that can be used to emulate the natural chemical processes of trace contaminants occurring in natural snow.

• MeSH
• Adsorption MeSH
• Models, Chemical MeSH
• Photochemical Processes MeSH
• Ketones analysis   chemistry   MeSH
• Air Pollutants analysis   chemistry   MeSH
• Environmental Monitoring methods   MeSH
• Surface Properties MeSH
• Snow chemistry   MeSH
• Temperature MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH