Radius je kritická kost pro funkci předloktí, a proto musí být jeho rekonstrukce v případě diafyzární zlomeniny anatomická ve všech rovinách a osách. Metodu volby představuje dlahová osteosyntéza, u které se však stále setkáváme s řadou zbytečných komplikací. Situaci nevyřešilo ani zavedení zamykacích dlah, ale spíše naopak. Proto je udivující, jak je diskuze anatomických a biomechanických principů dlahové osteosyntézy radia v současné literatuře redukována na minimum, nebo dokonce opomíjena. To se týká volby přístupu, typu dlahy, místa přiložení dlahy a jejího tvarování, pracovní délky dlahy, počtu šroubů a jejich rozložení na dlaze. Přitom je třeba si uvědomit, že dlahová fixace na radiu je namáhána nejen v ohybu, ale i v torzi. Na základě 30letých zkušeností i analýzy literatury prezentujeme naše názory na dlahovou osteosyntézu zlomenin diafýzy radia: Vždy preferujeme volární Henryho přístup, neboť umožňuje obnažit radius téměř v celé jeho délce a riziko poranění r. profundus n. radialis je minimální. Dosavadní studie nezjistily zásadní výhodu LCP dlah ve srovnání s 3.5 DCP nebo 3.5 LC DCP dlahami, spíše naopak. Důvodem je značná rigidita zamykacích dlah, determinovaný, a proto často nevyhovující směr zamykacích šroubů, zejména u dlah přiložených na volární plochu diafýzy a nerespektování fyziologického zakřivení radia při jejich aplikaci. Proto na základě vlastních zkušeností preferujeme použití „klasických“ DCP dlah 3.5 mm. Volární aplikace dlahy, zejména LCP dlahy, je spojena s řadou problémů. Tuto plochu, krytou prakticky v celém rozsahu svaly, je nutné nejdříve celou obnažit, což má negativní vliv na cévní zásobení kosti. Rovná dlaha v případě větší délky buď leží svým středem částečně mimo kost a překrývá margo interosseus, anebo její konce přečnívají přes kost zevně. Při použití zamykací dlahy s pevně determinovanou trajektorií šroubů procházejí tyto zamykací šrouby ve střední části dlahy mimo střed diafýzy pouze tenkou mezikostní hranou (mediální pozice) nebo jsou excentricky zavedeny krajní šrouby (laterální pozice). Obojí snižuje stabilitu osteosyntézy. Pokud dlaha překrývá margo interosseus, je obtížné kontrolovat vzájemný rotační vztah obou hlavních fragmentů. Použití kratší LCP dlahy zvyšuje rigiditu fixace, potlačuje tvorbu svalku a vede často k pakloubu. Laterální aplikace dlahy je z hlediska jejího ohybového i torzního namáhání výhodnější. Laterální plocha radia je plocha tahová, její distální polovina není kryta žádnými svaly, takže odpadá uvolnění svalů, margo interosseus není dlahou zakryto, a je tak možná bezpečná kontrola rotačního postavení úlomků. Správně předehnutá dlaha kopíruje fyziologické zakřivení laterální plochy radia. Dotažením normálních šroubů se oba hlavní úlomky přitáhnou do vrcholu konkavity dlahy a tím zvýší stabilitu osteosyntézy. Vzhledem k tvaru průřezu diafýzy radia je při laterálním přiložení dlahy dráha šroubů nejdelší. To zvyšuje rotační stabilitu. Dlahu přikládáme vždy v minimální délce tří otvorů na každém hlavním fragmentu. Příčné dvoufragmentové zlomeniny lze fixovat 2+2, tj. dvěma šrouby na každém hlavním fragmentu. Zlomeniny s interfragmentem nebo kominutivní zónou fixujeme v modu 3+3. U rozsáhlejších kominucí, defektů či segmentálních zlomenin jsou nutné 4 otvory dlahy na každém hlavním fragmentu, ne však více. Při vrtání otvorů pro šrouby je třeba vrták směřovat přímo proti margo interosseus. Šroub tak má nejdelší dráhu a nejlepší fixaci v kosti. Perforace volární či dorzální plochy radia významně zkracuje dráhu šroubu a tím snižuje stabilitu osteosyntézy.

Radius is a critical bone for functioning of the forearm and therefore its reconstruction following fracture of its shaft must be anatomical in all planes and along all axes. The method of choice is plate fixation. However, it is still associated with a number of unnecessary complications that were not resolved even by introduction of locking plates, but rather the opposite. All the more it is surprising that discussions about anatomical and biomechanical principles of plate fixation have been reduced to minimum or even neglected in the current literature. This applies primarily to the choice of the surgical approach, type of plate, site of its placement and contouring, its working length, number of screws and their distribution in the plate. At the same time it has to be taken into account that a plate used to fix radius is exposed to both bending and torsion stress. Based on our 30-year experience and analysis of literature we present our opinions on plate fixation of radial shaft fractures: We always prefer the volar Henry approach as it allows expose almost the whole of radius, with a minimal risk of injury to the deep branch of the radial nerve. The available studies have not so far found any substantial advantage of LCP plates as compared to 3.5mm DCP or 3.5mm LC DCP plates, quite the contrary. The reason is high rigidity of the locking plates, a determined trajectory of locking screws which is often unsuitable, mainly in plates placed on the anterior surface of the shaft, and failure to respect the physiological curvature of the radius. Therefore based on our experience we prefer “classical” 3.5mm DCP plates. Volar placement of the plate, LCP in particular, is associated with a number of problems. The volar surface covered almost entirely by muscles, must be fully exposed which negatively affects blood supply to the bone. A straight plate, if longer, either lies with its central part partially off the bone and overlaps the interosseous border, or its ends overhang the bone laterally. In a locking plate with a fixed determined trajectory of screws, the locking screws in the central holes of the plate pass off the shaft centre only through a thin interosseous border (medial position), or screws at the ends of the plate are inserted eccentrically (lateral position). Both these techniques reduce stability of internal fixation. Where the plate overlaps the interosseous border, it is difficult to control the mutual rotation of the two main fragments. A shorter LCP plate increases rigidity of fixation, suppresses bone healing and often leads to non-union. Placement of the plate on the lateral surface of the radius is more beneficial from the viewpoint of the bending and torsion stress. Lateral surface of the radius is a tension site, its distal half is not covered by muscles which eliminates the necessity to release them, the interosseous border is not obscured by plate and all this allows a safe control of rotational position of fragments. A properly pre-bent plate follows the physiological curvature of the lateral surface of the radius. Full tightening of standard screws will fix both main fragments firmly to the apex of plate concavity and increase stability of the internal fixation. Due to the shape of the cross-section of the radial shaft, the trajectory of screws is the longest in case of lateral placement of the plate, which increases rotational stability. We place the plate always in a minimal three-hole length on each main fragment. Transverse two-fragment fractures may be fixed with a 2+2 configuration, i.e. with two screws on each main fragment. Fractures with an inter-fragment or comminuted zone are fixed in the 3+3 mode. More extensive comminutions, defects or segmental fractures require 4 plate holes on each fragment, but not more. When drilling screw holes the drill must be directed into the interosseous border. As a result, the screw has the longest trajectory and the best fixation in the bone. Perforation of the anterior or posterior surface of the radius considerably shortens the trajectory of the screw and thus reduces stability of internal fixation.

• Keywords
• volární Henryho přístup,
• MeSH
• Biomechanical Phenomena MeSH
• Equipment Design MeSH
• Diaphyses surgery   injuries   MeSH
• Radius Fractures * surgery   MeSH
• Fracture Healing MeSH
• Bone Plates * adverse effects   utilization   MeSH
• Bone Screws MeSH
• Humans MeSH
• Forearm Injuries surgery   MeSH
• Radius surgery   MeSH
• Fracture Fixation, Internal * methods   instrumentation   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Review MeSH

Histone variants and their epigenetic modifications determine genome function, particularly transcription. However, whether regulation of gene expression can be influenced by nuclear organization or vice versa is not completely clear. Here, we analyzed the effect of epigenetic changes induced by a histone deacetylase inhibitor (HDACi) on the nuclear radial rearrangement of select genomic regions and chromosomes. The HDACi, sodium butyrate (NaBt), induced differentiation of human adenocarcinoma HT29 cells as well as a genome-wide increase in H3K9 acetylation. Three-dimensional analysis of nuclear radial distributions revealed that this increase in H3K9 acetylation was often associated with a repositioning of select loci and chromosomes toward the nuclear center. On the other hand, many centromeres resided sites more toward the nuclear periphery, similar to sites occupied by chromosome X. In more than two-thirds of events analyzed, central nuclear positioning correlated with a high level of H3K9 acetylation, while more peripheral positioning within interphase nuclei correlated with a lower level of acetylation. This was observed for the gene-rich chromosomes 17 and 19, TP53, and CCND1 genes as well as for gene-poor chromosome 18, APC gene, regions of low transcriptional activity (anti-RIDGEs), and the relatively transcriptionally less active chromosome X. These results are consistent with a role for epigenetic histone modifications in governing the nuclear radial positioning of genomic regions during differentiation.

• MeSH
• Acetylation MeSH
• Adenocarcinoma enzymology   genetics   MeSH
• Cell Differentiation MeSH
• Cell Nucleus enzymology   pathology   drug effects   MeSH
• HT29 Cells MeSH
• Butyrates pharmacology   MeSH
• Cyclin D1 genetics   MeSH
• Enterocytes drug effects   enzymology   pathology   MeSH
• Epigenesis, Genetic drug effects   MeSH
• Financing, Organized MeSH
• Genes, APC MeSH
• Histone Deacetylases MeSH
• Histones metabolism   MeSH
• Enzyme Inhibitors pharmacology   MeSH
• Histone Deacetylase Inhibitors MeSH
• Humans MeSH
• Chromosomes, Human, Pair 17 metabolism   MeSH
• Chromosomes, Human, Pair 18 metabolism   MeSH
• Chromosomes, Human, Pair 19 metabolism   MeSH
• Chromosomes, Human metabolism   MeSH
• Tumor Suppressor Protein p53 genetics   MeSH
• Colonic Neoplasms enzymology   genetics   MeSH
• Protein Processing, Post-Translational drug effects   MeSH
• Cell Proliferation MeSH
• Promoter Regions, Genetic MeSH
• Gene Expression Regulation, Neoplastic MeSH
• Chromatin Assembly and Disassembly drug effects   MeSH
• Check Tag
• Humans MeSH

Odborná příručka se věnuje problematice klinických funkčních testů, například srdce, dále respiračním funkčním testům, funkčním testům ledvin, jater, trávicího ústrojí a nervového systému a dalším funkčním testům.

• MeSH
• Diagnostic Techniques and Procedures MeSH
• Heart Function Tests MeSH
• Respiratory Function Tests MeSH
• Internal Medicine MeSH
• Publication type
• Handbook MeSH

• Conspectus
• Lékařské vědy. Lékařství
• NML Fields
• lékařství
• vnitřní lékařství
• NML Publication type
• kolektivní monografie

Parkinson's disease (PD) is a neurodegenerative disorder which impairs motor skills, speech, and other functions such as behavior, mood, and cognitive processes. One of the most typical clinical hallmarks of PD is handwriting deterioration, usually the first manifestation of PD. The aim of this study is twofold: (a) to find a subset of handwriting features suitable for identifying subjects with PD and (b) to build a predictive model to efficiently diagnose PD. We collected handwriting samples from 37 medicated PD patients and 38 age- and sex-matched controls. The handwriting samples were collected during seven tasks such as writing a syllable, word, or sentence. Every sample was used to extract the handwriting measures. In addition to conventional kinematic and spatio-temporal handwriting measures, we also computed novel handwriting measures based on entropy, signal energy, and empirical mode decomposition of the handwriting signals. The selected features were fed to the support vector machine classifier with radial Gaussian kernel for automated diagnosis. The accuracy of the classification of PD was as high as 88.13%, with the highest values of sensitivity and specificity equal to 89.47% and 91.89%, respectively. Handwriting may be a valuable marker as a diagnostic and screening tool.

• MeSH
• Algorithms MeSH
• Biomarkers MeSH
• Biomechanical Phenomena MeSH
• Energy Metabolism MeSH
• Entropy MeSH
• Middle Aged MeSH
• Humans MeSH
• Neuropsychological Tests MeSH
• Normal Distribution MeSH
• Parkinson Disease * diagnosis   psychology   therapy   MeSH
• Aged MeSH
• Support Vector Machine MeSH
• Decision Support Systems, Clinical * MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH

The role of width of Gaussians in two types of computational models is investigated: Gaussian radial-basis-functions (RBFs) where both widths and centers vary and Gaussian kernel networks which have fixed widths but varying centers. The effect of width on functional equivalence, universal approximation property, and form of norms in reproducing kernel Hilbert spaces (RKHS) is explored. It is proven that if two Gaussian RBF networks have the same input-output functions, then they must have the same numbers of units with the same centers and widths. Further, it is shown that while sets of input-output functions of Gaussian kernel networks with two different widths are disjoint, each such set is large enough to be a universal approximator. Embedding of RKHSs induced by "flatter" Gaussians into RKHSs induced by "sharper" Gaussians is described and growth of the ratios of norms on these spaces with increasing input dimension is estimated. Finally, large sets of argminima of error functionals in sets of input-output functions of Gaussian RBFs are described.

• MeSH
• Algorithms * MeSH
• Neural Networks, Computer * MeSH
• Normal Distribution MeSH
• Computer Simulation * MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Directional organ growth allows the plant root system to strategically cover its surroundings. Intercellular auxin transport is aligned with the gravity vector in the primary root tips, facilitating downward organ bending at the lower root flank. Here we show that cytokinin signaling functions as a lateral root specific anti-gravitropic component, promoting the radial distribution of the root system. We performed a genome-wide association study and reveal that signal peptide processing of Cytokinin Oxidase 2 (CKX2) affects its enzymatic activity and, thereby, determines the degradation of cytokinins in natural Arabidopsis thaliana accessions. Cytokinin signaling interferes with growth at the upper lateral root flank and thereby prevents downward bending. Our interdisciplinary approach proposes that two phytohormonal cues at opposite organ flanks counterbalance each other's negative impact on growth, suppressing organ growth towards gravity and allow for radial expansion of the root system.

• MeSH
• Arabidopsis physiology   MeSH
• Genome-Wide Association Study MeSH
• Cytokinins metabolism   MeSH
• Plants, Genetically Modified physiology   MeSH
• Genome, Plant genetics   MeSH
• Gravitropism MeSH
• Plant Roots metabolism   MeSH
• Oxidoreductases genetics   metabolism   MeSH
• Arabidopsis Proteins metabolism   MeSH
• Proteolysis MeSH
• Plant Growth Regulators metabolism   MeSH
• Systems Biology MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

• MeSH
• Physical Phenomena MeSH
• Magnetic Resonance Imaging MeSH

• Conspectus
• Patologie. Klinická medicína
• NML Fields
• radiologie, nukleární medicína a zobrazovací metody
• NML Publication type
• kolektivní monografie

The localisation and distribution of the serotoninergic nerve elements was studied for the first time in the flatworm Chimaericola leptogaster (Leuckart, 1830) using immunocytochemical methodology and confocal laser scanning microscopy. The musculature was investigated by histochemical staining of actin filaments; scanning electron microscopy was used to identify the sensory structures on the worm's surface. Uniciliated, bi-ciliated and multiciliated sensory endings have been described on the worm's surface. The morphological data demonstrate the presence of circular, longitudinal and diagonal muscles that comprise the musculature of C. leptogaster in the anterior, median and posterior body regions. Well-developed radial and circular muscle fibres were also observed surrounding the genital pore, two vaginae and in clumps of the haptor. The study revealed the presence of biogenic amine, serotonin, in the central and peripheral nervous systems of C. leptogaster: in the neurons and fibres of the cephalic ganglia and ventral nerve cord, in the innervation of reproductive system compartments. The localised sites of the serotoninergic elements point to important roles of serotonin in monogenean reproductive processes and, possibly, in the regulation of muscle function.

• MeSH
• Immunohistochemistry veterinary   MeSH
• Microscopy, Confocal veterinary   MeSH
• Microscopy, Electron, Scanning veterinary   MeSH
• Nervous System Physiological Phenomena * MeSH
• Nervous System cytology   ultrastructure   MeSH
• Fishes parasitology   MeSH
• Serotonin analysis   MeSH
• Muscles cytology   ultrastructure   MeSH
• Trematoda cytology   physiology   ultrastructure   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

To meet the need for Parkinson's disease biomarkers and evidence for amount and distribution of pathological changes, MRI diffusion tensor imaging (DTI) has been explored in a number of previous studies. However, conflicting results warrant further investigations. As tissue microstructure, particularly of the grey matter, is heterogeneous, a more precise diffusion model may benefit tissue characterization. The purpose of this study was to analyze the diffusion-based imaging technique restriction spectrum imaging (RSI) and DTI, and their ability to detect microstructural changes within brain regions associated with motor function in Parkinson's disease. Diffusion weighted (DW) MR images of a total of 100 individuals, (46 Parkinson's disease patients and 54 healthy controls) were collected using b-values of 0-4000s/mm2. Output diffusion-based maps were estimated based on the RSI-model combining the full set of DW-images (Cellular Index (CI), Neurite Density (ND)) and DTI-model combining b = 0 and b = 1000 s/mm2 (fractional anisotropy (FA), Axial-, Mean- and Radial diffusivity (AD, MD, RD)). All parametric maps were analyzed in a voxel-wise group analysis, with focus on typical brain regions associated with Parkinson's disease pathology. CI, ND and DTI diffusivity metrics (AD, MD, RD) demonstrated the ability to differentiate between groups, with strongest performance within the thalamus, prone to pathology in Parkinson's disease. Our results indicate that RSI may improve the predictive power of diffusion-based MRI, and provide additional information when combined with the standard diffusivity measurements. In the absence of major atrophy, diffusion techniques may reveal microstructural pathology. Our results suggest that protocols for MRI diffusion imaging may be adapted to more sensitive detection of pathology at different sites of the central nervous system.

• MeSH
• Nerve Degeneration diagnosis   diagnostic imaging   pathology   MeSH
• Diagnostic Imaging * MeSH
• Diffusion Magnetic Resonance Imaging MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Brain Stem diagnostic imaging   pathology   MeSH
• Parkinson Disease diagnosis   diagnostic imaging   pathology   MeSH
• Gray Matter diagnostic imaging   pathology   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Substantia Nigra diagnostic imaging   pathology   MeSH
• Thalamus diagnostic imaging   pathology   MeSH
• Diffusion Tensor Imaging * MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

• Conspectus
• Hygiena. Lidské zdraví
• NML Fields
• hyperbarická a letecká medicína