Cílem práce bylo zkoumat vztah mezi zobecněnou entropií diskrétní náhodné veličiny (tzv. f-entropií, třídou funkcí, zahrnující řadu indexů používaných pří měření biodiverzity) a minimální Bayesovskou pravděpodobností chyby při odhadu hodnoty této náhodné veličiny. Zejména studovat těsnost jejich vztahu. Morales a Vajda [1] nedávno zavedli míru zvanou průměrná nepřesnost (average inaccuracy), která kvantifikuje těsnost vztahu mezi aposteriorní Bayesovskou pravděpodobností chyby a mocninnými entropiemi. Tato míra je definována jako normalizovaný průměrný rozdíl horní a dolní meze aposteriorní Bayesovské pravděpodobnosti chyby za dané entropie. Tuto míru je možno zobecnit na jakoukoli striktně konkávní f-entropii a použít ji k vyjádření těsnosti vztahu této f-entropie k aposteriorní Bayesovské pravděpodobnosti chyby. Získaný vztah je však většinou poměrně složitý a není možné snadno analyticky porovnat průměrné nepřesnosti různých f-entropií. Navrhujeme hladkou aproximaci dolní meze aposteriorní Bayesovské pravděpodobnosti chyby za dané f-entropie, jejíž použití zjednoduší formuli průměrné nepřesnosti. Ukázali jsme, že při použití této aproximace má kvadratická entropie nejtěsnější vztah k aposteriorní Bayesovské pravděpodobnosti chyby mezi f-entropiemi. Kvadratická entropie má těsnější vztah k Bayesovské pravděpodobnosti chyby (ve smyslu popsaném v článku) než Shannonova entropie a další funkce příslušící do třídy f-entropií, jako např. Emlenův index, Ferreriho index, Goodův index a další.

We deal with the relation between the generalized entropy (f-entropy, a family of functions that include several biodiversity measures) of a discrete random variable and the minimal probability of error (Bayes error) when the value of this random variable is estimated. Namely the tightness of their relation is studied. Morales and Vajda [1] recently introduced a measure called average inaccuracy that aims to quantify the tightness of the relation between the posterior Bayes error and the power entropies. It is defined as a standardized average difference between the upper and the lower bound for the posterior Bayes error under given entropy. Their concept can be generalized to any strictly concave f-entropy and used to evaluate its relation to the Bayes probability of error. However, due to a complex form of the formula of the average inaccuracy, it is difficult to compare the average inaccuracies of most f-entropies analytically. We propose a smooth approximation of the lower bound for the posterior Bayes error under given f-entropy that simplifies the formula of the average inaccuracy. We show that under this approximation, the quadratic entropy has the tightest relation to the posterior Bayes error among f-entropies. The quadratic entropy has the tightest relation to the posterior Bayes error (in the sense described in this paper) than the Shannon’s entropy and other functions that belong to the family of f-entropies, like Emlen’s index, Ferreri’s index and Good’s index.

• Klíčová slova
• zobecněná entropie, f-entropie, Bayesovská pravděpodobnost chyby, průměrná nepřesnost, mocninná entropie, kvadratická entropie, Shannonova entropie, Emlenův index, Ferreriho index, Goodův index,
• MeSH
• algoritmy MeSH
• Bayesova věta MeSH
• entropie MeSH
• financování organizované MeSH

Among the main challenges of the predictive brain/mind concept is how to link prediction at the neural level to prediction at the cognitive-psychological level and finding conceptually robust and empirically verifiable ways to harness this theoretical framework toward explaining higher-order mental and cognitive phenomena, including the subjective experience of aesthetic and symbolic forms. Building on the tentative prediction error account of visual art, this article extends the application of the predictive coding framework to the visual arts. It does so by linking this theoretical discussion to a subjective, phenomenological account of how a work of art is experienced. In order to engage more deeply with a work of art, viewers must be able to tune or adapt their prediction mechanism to recognize art as a specific class of objects whose ontological nature defies predictability, and they must be able to sustain a productive flow of predictions from low-level sensory, recognitional to abstract semantic, conceptual, and affective inferences. The affective component of the process of predictive error optimization that occurs when a viewer enters into dialog with a painting is constituted both by activating the affective affordances within the image and by the affective consequences of prediction error minimization itself. The predictive coding framework also has implications for the problem of the culturality of vision. A person's mindset, which determines what top-down expectations and predictions are generated, is co-constituted by culture-relative skills and knowledge, which form hyperpriors that operate in the perception of art.

• Publikační typ
• časopisecké články MeSH

OBJECTIVES: Compare overall Landing Error Scoring System (LESS) scores, risk categorisation, specific LESS errors, and double-leg jump-landing jump heights between overhead goal and no goal conditions. DESIGN: Randomised cross-over. SETTING: Laboratory. PARTICIPANTS: 76 (51% male). MAIN OUTCOME MEASURES: Participants landed from a 30-cm box to 50% of their body height and immediately jumped vertically for maximum height. Participants completed three trials under two random-ordered conditions: with and without overhead goal. Group-level mean LESS scores, risk categorisation (5-error threshold), specific landing errors, and jump heights were compared between conditions. RESULTS: Mean LESS scores were greater (0.3 errors, p < 0.001) with the overhead goal, but this small difference was not clinically meaningful. Similarly, although the number of high-risk participants was greater with the overhead goal (p = 0.039), the 9.2% difference was trivial. Participants jumped 2.7 cm higher with the overhead goal (p < 0.001) without affecting the occurrence of any specific LESS errors. DISCUSSION: Performing the LESS with an overhead goal enhances sport specificity and elicits greater vertical jump performances with minimal change in landing errors and injury-risk categorisation. Adding an overhead goal to LESS might enhance its suitability for injury risk screening, although the predictive value of LESS with an overhead goal needs confirmation.

• MeSH
• klinické křížové studie MeSH
• kolenní kloub MeSH
• lidé MeSH
• pohyb MeSH
• poranění předního zkříženého vazu * MeSH
• sporty * MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH

We argue that prediction success maximization is a basic objective of cognition and cortex, that it is compatible with but distinct from prediction error minimization, that neither objective requires subtractive coding, that there is clear neurobiological evidence for the amplification of predicted signals, and that we are unconvinced by evidence proposed in support of subtractive coding. We outline recent discoveries showing that pyramidal cells on which our cognitive capabilities depend usually transmit information about input to their basal dendrites and amplify that transmission when input to their distal apical dendrites provides a context that agrees with the feedforward basal input in that both are depolarizing, i.e., both are excitatory rather than inhibitory. Though these intracellular discoveries require a level of technical expertise that is beyond the current abilities of most neuroscience labs, they are not controversial and acclaimed as groundbreaking. We note that this cellular cooperative context-sensitivity greatly enhances the cognitive capabilities of the mammalian neocortex, and that much remains to be discovered concerning its evolution, development, and pathology.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

During the minimally-invasive liver surgery, only the partial surface view of the liver is usually provided to the surgeon via the laparoscopic camera. Therefore, it is necessary to estimate the actual position of the internal structures such as tumors and vessels from the pre-operative images. Nevertheless, such task can be highly challenging since during the intervention, the abdominal organs undergo important deformations due to the pneumoperitoneum, respiratory and cardiac motion and the interaction with the surgical tools. Therefore, a reliable automatic system for intra-operative guidance requires fast and reliable registration of the pre- and intra-operative data. In this paper we present a complete pipeline for the registration of pre-operative patient-specific image data to the sparse and incomplete intra-operative data. While the intra-operative data is represented by a point cloud extracted from the stereo-endoscopic images, the pre-operative data is used to reconstruct a biomechanical model which is necessary for accurate estimation of the position of the internal structures, considering the actual deformations. This model takes into account the patient-specific liver anatomy composed of parenchyma, vascularization and capsule, and is enriched with anatomical boundary conditions transferred from an atlas. The registration process employs the iterative closest point technique together with a penalty-based method. We perform a quantitative assessment based on the evaluation of the target registration error on synthetic data as well as a qualitative assessment on real patient data. We demonstrate that the proposed registration method provides good results in terms of both accuracy and robustness w.r.t. the quality of the intra-operative data.

• MeSH
• biologické modely * MeSH
• individualizovaná medicína metody   MeSH
• játra chirurgie   MeSH
• lidé MeSH
• miniinvazivní chirurgické výkony metody   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

U starších pacientů – zejména u těch, kteří užívají alespoň pět léčiv – se běžně vyskytují nežádoucí účinky léčiv, ovšem tyto projevy lze předvídat a často jim lze i předcházet. Racionální přístup k předepisování léčiv starším osobám vychází z propojení znalostí fyziologických změn spojených se stárnutím a farmako­logie. Základem opatrného a spolehlivého přístupu k předepisování léčiv je pro ­rodinného lékaře soustředění na specifické výsledné stavy, např. na rychlé ­rozpoznání nežádoucích účinků léčiv. Lékaři se musejí naučit usměrňovat ­průběh léčby, mj. pravidelným hodnocením všech užívaných léčiv podle Beersových ­kritérií, a tím, že nebudou předepisovat nová léčiva s cílem odstranit nežádoucí účinky jiných farmak. Výskyt nežádoucích účinků léčiv lze snížit používáním počítačových programů, které generují varování, a uplatňováním multidisciplinárního přístupu.

Adverse drug events are common in older patients, particularly in those taking at least five medications, but such events are predictable and often preventable. A rational approach to prescribing in older adults integrates physiologic changes of aging with knowledge of pharmacology. Focusing on specific outcomes, such as the prompt recognition of adverse drug events, allows the family physician to approach prescribing cautiously and confidently. Physicians need to find ways to streamline the medical regimen, such as periodically reviewing all medications in relation to the Beers criteria and avoiding new prescriptions to counteract adverse drug reactions. The incorporation of computerized alerts and a multidisciplinary approach can reduce adverse drug events.

• MeSH
• hodnocení rizik MeSH
• informační služby o lécích normy   MeSH
• lékové předpisy normy   MeSH
• lidé MeSH
• medikační omyly prevence a kontrola   MeSH
• počítačová farmakoterapie kontraindikace   MeSH
• primární zdravotní péče normy   MeSH
• senioři MeSH
• spotřeba léčiv normy   MeSH
• Check Tag
• lidé MeSH
• senioři MeSH

BACKGROUND: Treponema pallidum ssp. pallidum (TPA), the causative agent of syphilis, is a highly clonal bacterium showing minimal genetic variability in the genome sequence of individual strains. Nevertheless, genetically characterized syphilis strains can be clearly divided into two groups, Nichols-like strains and SS14-like strains. TPA Nichols and SS14 strains were completely sequenced in 1998 and 2008, respectively. Since publication of their complete genome sequences, a number of sequencing errors in each genome have been reported. Therefore, we have resequenced TPA Nichols and SS14 strains using next-generation sequencing techniques. METHODOLOGY/PRINCIPAL FINDINGS: The genomes of TPA strains Nichols and SS14 were resequenced using the 454 and Illumina sequencing methods that have a combined average coverage higher than 90x. In the TPA strain Nichols genome, 134 errors were identified (25 substitutions and 109 indels), and 102 of them affected protein sequences. In the TPA SS14 genome, a total of 191 errors were identified (85 substitutions and 106 indels) and 136 of them affected protein sequences. A set of new intrastrain heterogenic regions in the TPA SS14 genome were identified including the tprD gene, where both tprD and tprD2 alleles were found. The resequenced genomes of both TPA Nichols and SS14 strains clustered more closely with related strains (i.e. strains belonging to same syphilis treponeme subcluster). At the same time, groups of Nichols-like and SS14-like strains were found to be more distantly related. CONCLUSION/SIGNIFICANCE: We identified errors in 11.5% of all annotated genes and, after correction, we found a significant impact on the predicted proteomes of both Nichols and SS14 strains. Corrections of these errors resulted in protein elongations, truncations, fusions and indels in more than 11% of all annotated proteins. Moreover, it became more evident that syphilis is caused by treponemes belonging to two separate genetic subclusters.

• MeSH
• fylogeneze MeSH
• genetická variace MeSH
• genom genetika   MeSH
• molekulární sekvence - údaje MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sekvenční analýza DNA metody   MeSH
• sekvenční seřazení MeSH
• syfilis genetika   parazitologie   MeSH
• Treponema pallidum genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem 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

Even though chemotherapy and immunotherapy emerged to limit continual and unregulated proliferation of cancer cells, currently available therapeutic agents are associated with high toxicity levels and low success rates. Additionally, ongoing multi-targeted therapies are limited only for few carcinogenesis pathways, due to continually emerging and evolving mutations of proto-oncogenes and tumor-suppressive genes. CRISPR/Cas9, as a specific gene-editing tool, is used to correct causative mutations with minimal toxicity, but is also employed as an adjuvant to immunotherapy to achieve a more robust immunological response. Some of the most critical limitations of the CRISPR/Cas9 technology include off-target mutations, resulting in nonspecific restrictions of DNA upstream of the Protospacer Adjacent Motifs (PAM), ethical agreements, and the lack of a scientific consensus aiming at risk evaluation. Currently, CRISPR/Cas9 is tested on animal models to enhance genome editing specificity and induce a stronger anti-tumor response. Moreover, ongoing clinical trials use the CRISPR/Cas9 system in immune cells to modify genomes in a target-specific manner. Recently, error-free in vitro systems have been engineered to overcome limitations of this gene-editing system. The aim of the article is to present the knowledge concerning the use of CRISPR Cas9 technique in targeting treatment-resistant cancers. Additionally, the use of CRISPR/Cas9 is aided as an emerging supplementation of immunotherapy, currently used in experimental oncology. Demonstrating further, applications and advances of the CRISPR/Cas9 technique are presented in animal models and human clinical trials. Concluding, an overview of the limitations of the gene-editing tool is proffered.

• MeSH
• CRISPR-Cas systémy * MeSH
• editace genu * MeSH
• genetická terapie * MeSH
• imunoterapie adoptivní MeSH
• imunoterapie * MeSH
• individualizovaná medicína metody   MeSH
• klinické zkoušky jako téma MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• nádory etiologie   terapie   MeSH
• nemoc MeSH
• preklinické hodnocení léčiv MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

• MeSH
• matematické výpočty počítačové MeSH
• matematika MeSH
• numerická analýza pomocí počítače * MeSH
• Publikační typ
• monografie MeSH

• Konspekt
• Počítačová věda. Výpočetní technika. Informační technologie
• NLK Obory
• přírodní vědy
• přírodní vědy