Generalized hypermobility is associated with higher rates of musculoskeletal injuries, a trend also observed in volleyball. We aimed to investigate how asymptomatic hypermobility affects other suggested lower limb injury risk factors. Fifty female volleyball players (22 hypermobile, 28 non-hypermobile) were assessed using Beighton scores (BS) and lower limb injury risk factors based on the Landing Error Scoring System, single-leg dynamic balance, and Limb Symmetry Index (LSI) for single-leg hop and triple hop for distance. Spearman's correlations assessed relationships between BS and the risk factors, and t-tests or Mann-Whitney U tests compared risk factors between non-hypermobile and asymptomatic hypermobile groups. No significant associations were found between BS and most risk factors, except for a negative correlation with the centre of pressure range of motion in the medio-lateral direction during dynamic balance on the non-dominant leg (ρ = -0.332; p = 0.015). The only significant group difference was in the LSI for single-leg hop distance, where the hypermobile group showed greater symmetry (r = 0.28, p = 0.041). The association between BS and dynamic balance was weak, with no clear difference in injury risk factors were observed between groups, suggesting hypermobile players may not need specialized training programs.

• Klíčová slova
• Beighton score, Landing Error Scoring System, Limb Symmetry Index, balance, injury risk, movement screen,
• MeSH
• dolní končetina * zranění   MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nestabilita kloubu * patofyziologie   komplikace   MeSH
• posturální rovnováha fyziologie   MeSH
• rizikové faktory MeSH
• rozsah kloubních pohybů MeSH
• sportovní úrazy * etiologie   MeSH
• volejbal * zranění   MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Protein acetylation has emerged as essential for sperm function, attracting considerable attention recently. Acetylation, typically mediated by lysine acetyltransferases, involves attaching an acetyl group from acetyl-coenzyme A to lysine residues in proteins. Under alkaline conditions, however, acetylation can occur with minimal enzymatic involvement, primarily due to an elevated pH. As sperm migrate towards the ampulla, they experience increasing intracellular pH (pHi) while undergoing two crucial processes for fertilization: capacitation and the acrosome reaction (AR). Whereas the involvement of acetylating enzymes in these events has been partially investigated, the potential for non-enzymatic acetylation driven by the pHi alkalinization remains unknown. RESULTS: This study examined protein acetylation (acLys) levels in sperm incubated under capacitating conditions at pH 7.2 and pH 9.0, the latter condition potentially promoting non-enzymatic acetylation. To more precisely investigate the occurrence of non-enzymatic acetylation events, acetyltransferase activity was selectively attenuated using a specific cocktail of inhibitors. The functional implications of these conditions were assessed by examining key fertilization-related sperm attributes, including motility during capacitation and the ability to initiate the AR. Results demonstrated that alkaline conditions elevated basal acLys levels even with reduced acetyltransferase activity (P < 0.05), indicative of non-enzymatic acetylation. α-tubulin, particularly in the midpiece of the sperm flagellum, was identified as a specific target of this modification, correlating with diminished motility during capacitation. Following the AR, acLys levels in the head and midpiece decreased (P < 0.05) under conditions promoting non-enzymatic acetylation, accompanied by reductions in intracellular and acrosomal pH. In contrast, acLys levels and pH in the sperm head incubated under standard capacitating conditions (pH 7.2) remained stable. Sperm exposed to conditions conducive to non-enzymatic acetylation exhibited an impaired ability to trigger the AR (P < 0.05) compared to those maintained at pH 7.2. Notably, diminished acetylase activity emerged as a key factor impairing the maintenance of intracellular and acrosomal pH levels attained during capacitation, even under a pH of 9.0. CONCLUSION: This study provides novel evidence for the occurrence of non-enzymatic acetylation in sperm, linked to the modulation of α-tubulin acetylation levels and motility during capacitation. Additionally, it suggests that acetyltransferase activity may play a crucial role in regulating intracellular and acrosomal pH levels in capacitated sperm, facilitating the AR.

• Klíčová slova
• Acrosome reaction, Motility, Non-enzymatic acetylation, Sperm capacitation, pH, α-tubulin,
• MeSH
• acetylace MeSH
• akrozomální reakce * fyziologie   MeSH
• fertilizace * fyziologie   MeSH
• kapacitace spermií * fyziologie   MeSH
• koncentrace vodíkových iontů MeSH
• motilita spermií fyziologie   MeSH
• spermie * metabolismus   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

In therapeutic diagnostics, early diagnosis and monitoring of heart disease is dependent on fast time-series MRI data processing. Robust encryption techniques are necessary to guarantee patient confidentiality. While deep learning (DL) algorithm have improved medical imaging, privacy and performance are still hard to balance. In this study, a novel approach for analyzing homomorphivally-encrypted (HE) time-series MRI data is introduced: The Multi-Faceted Long Short-Term Memory (MF-LSTM). This method includes privacy protection. The MF-LSTM architecture protects patient's privacy while accurately categorizing and forecasting cardiac disease, with accuracy (97.5%), precision (96.5%), recall (98.3%), and F1-score (97.4%). While segmentation methods help to improve interpretability by identifying important region in encrypted MRI images, Generalized Histogram Equalization (GHE) improves image quality. Extensive testing on selected dataset if encrypted time-series MRI images proves the method's stability and efficacy, outperforming previous approaches. The finding shows that the suggested technique can decode medical image to expose visual representation as well as sequential movement while protecting privacy and providing accurate medical image evaluation.

• Klíčová slova
• Encryption, Heart Disease, MRI Images, Multi-faceted long short-term memory (MF-LSTM),
• MeSH
• algoritmy MeSH
• deep learning MeSH
• důvěrnost informací MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie * metody   MeSH
• nemoci srdce * diagnostické zobrazování   MeSH
• neuronové sítě MeSH
• počítačové zpracování obrazu metody   MeSH
• soukromí * MeSH
• zabezpečení počítačových systémů MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROND: One of the important areas of heart research is to analyze heart rate variability during (HRV) walking. OBJECTIVE: In this research, we investigated the correction between heart activation and the variations of walking paths. METHOD: We employed Shannon entropy to analyze how the information content of walking paths affects the information content of HRV. Eight healthy students walked on three designed walking paths with different information contents while we recorded their ECG signals. We computed and analyzed the Shannon entropy of the R-R interval time series (as an indicator of HRV) versus the Shannon entropy of different walking paths and accordingly evaluated their relation. RESULTS: According to the obtained results, walking on the path that contains more information leads to less information in the R-R time series. CONCLUSION: The analysis method employed in this research can be extended to analyze the relation between other physiological signals (such as brain or muscle reactions) and the walking path.

• Klíčová slova
• Heart Rate Variability (HRV), R-R interval time series, Shannon entropy, information content, walking path,
• MeSH
• časové faktory MeSH
• chůze * MeSH
• elektrokardiografie * MeSH
• entropie MeSH
• lidé MeSH
• srdeční frekvence fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Analysis of the reactions of different organs to external stimuli is an important area of research in physiological science. OBJECTIVE: In this paper, we investigated the correlation between the brain and facial muscle activities by information-based analysis of electroencephalogram (EEG) signals and electromyogram (EMG) signals using Shannon entropy. METHOD: The EEG and EMG signals of thirteen subjects were recorded during rest and auditory stimulations using relaxing, pop, and rock music. Accordingly, we calculated the Shannon entropy of these signals. RESULTS: The results showed that rock music has a greater effect on the information of EEG and EMG signals than pop music, which itself has a greater effect than relaxing music. Furthermore, a strong correlation (r= 0.9980) was found between the variations of the information of EEG and EMG signals. CONCLUSION: The activities of the facial muscle and brain are correlated in different conditions. This technique can be utilized to investigate the correlation between the activities of different organs versus brain activity in different situations.

• Klíčová slova
• EEG signals, EMG signals, Facial muscle, Shannon entropy, brain, correlation, information,
• MeSH
• akustická stimulace MeSH
• elektroencefalografie * metody   MeSH
• elektromyografie metody   MeSH
• lidé MeSH
• mozek fyziologie   MeSH
• obličejové svaly * fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Objective.Functional specialization is fundamental to neural information processing. Here, we study whether and how functional specialization emerges in artificial deep convolutional neural networks (CNNs) during a brain-computer interfacing (BCI) task.Approach.We trained CNNs to predict hand movement speed from intracranial electroencephalography (iEEG) and delineated how units across the different CNN hidden layers learned to represent the iEEG signal.Main results.We show that distinct, functionally interpretable neural populations emerged as a result of the training process. While some units became sensitive to either iEEG amplitude or phase, others showed bimodal behavior with significant sensitivity to both features. Pruning of highly sensitive units resulted in a steep drop of decoding accuracy not observed for pruning of less sensitive units, highlighting the functional relevance of the amplitude- and phase-specialized populations.Significance.We anticipate that emergent functional specialization as uncovered here will become a key concept in research towards interpretable deep learning for neuroscience and BCI applications.

• Klíčová slova
• brain–computer interface (BCI), deep learning, explainable AI (XAI), internal representation, intracranial EEG (iEEG), motor decoding, neural network visualization,
• MeSH
• algoritmy MeSH
• elektroencefalografie metody   MeSH
• mozek MeSH
• neuronové sítě MeSH
• rozhraní mozek-počítač * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The accurate decoding of facial emotion expressions lies at the center of many research traditions in psychology. Much of this research, while paying lip service to the importance of context in emotion perception, has used stimuli that were carefully created to be deprived of contextual information. The participants' task is to associate the expression shown in the face with a correct label, essentially changing a social perception task into a cognitive task. In fact, in many cases, the task can be carried out correctly without engaging emotion recognition at all. The present article argues that infusing context in emotion perception does not only add an additional source of information but changes the way that participants approach the task by rendering it a social perception task rather than a cognitive task. Importantly, distinguishing between accuracy (perceiving the intended emotions) and bias (perceiving additional emotions to those intended) leads to a more nuanced understanding of social emotion perception. Results from several studies that use the Assessment of Contextual Emotions demonstrate the significance and social functionality of simultaneously considering emotion decoding accuracy and bias for social interaction in different cultures, their key personality and societal correlates, and their function for close relationships processes.

• Klíčová slova
• accuracy, bias, emotion perception, social perception,
• MeSH
• emoce * MeSH
• lidé MeSH
• osobnost MeSH
• sociální percepce MeSH
• výraz obličeje * MeSH
• zkreslení výsledků (epidemiologie) MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Rhomboid intramembrane proteases regulate pathophysiological processes, but their targeting in a disease context has never been achieved. We decoded the atypical substrate specificity of malaria rhomboid PfROM4, but found, unexpectedly, that it results from "steric exclusion": PfROM4 and canonical rhomboid proteases cannot cleave each other's substrates due to reciprocal juxtamembrane steric clashes. Instead, we engineered an optimal sequence that enhanced proteolysis >10-fold, and solved high-resolution structures to discover that boronates enhance inhibition >100-fold. A peptide boronate modeled on our "super-substrate" carrying one "steric-excluding" residue inhibited PfROM4 but not human rhomboid proteolysis. We further screened a library to discover an orthogonal alpha-ketoamide that potently inhibited PfROM4 but not human rhomboid proteolysis. Despite the membrane-immersed target and rapid invasion, ultrastructural analysis revealed that single-dosing blood-stage malaria cultures blocked host-cell invasion and cleared parasitemia. These observations establish a strategy for designing parasite-selective rhomboid inhibitors and expose a druggable dependence on rhomboid proteolysis in non-motile parasites.

• Klíčová slova
• Plasmodium, Ras-converting enzyme, Toxoplasma, apicomplexan parasites, malaria, presenilin, regulated intramembrane proteolysis, rhomboid protease, serine protease, site-2 protease,
• MeSH
• amidy chemická syntéza   chemie   farmakologie   MeSH
• antimalarika chemická syntéza   chemie   farmakologie   MeSH
• HEK293 buňky MeSH
• inhibitory proteas chemická syntéza   chemie   farmakologie   MeSH
• kyseliny boronové chemická syntéza   chemie   farmakologie   MeSH
• lidé MeSH
• malárie krev   farmakoterapie   metabolismus   MeSH
• molekulární struktura MeSH
• parazitické testy citlivosti MeSH
• peptidy chemická syntéza   chemie   farmakologie   MeSH
• Plasmodium falciparum účinky léků   metabolismus   MeSH
• proteasy krev   metabolismus   MeSH
• proteolýza účinky léků   MeSH
• protozoální proteiny antagonisté a inhibitory   krev   metabolismus   MeSH
• racionální návrh léčiv * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• amidy MeSH
• antimalarika MeSH
• inhibitory proteas MeSH
• kyseliny boronové MeSH
• peptidy MeSH
• proteasy MeSH
• protozoální proteiny MeSH
• ROM4 protein, Plasmodium falciparum MeSH Prohlížeč

Ribosomes accurately decode mRNA by proofreading each aminoacyl-tRNA that is delivered by the elongation factor EF-Tu1. To understand the molecular mechanism of this proofreading step it is necessary to visualize GTP-catalysed elongation, which has remained a challenge2-4. Here we use time-resolved cryogenic electron microscopy to reveal 33 ribosomal states after the delivery of aminoacyl-tRNA by EF-Tu•GTP. Instead of locking cognate tRNA upon initial recognition, the ribosomal decoding centre dynamically monitors codon-anticodon interactions before and after GTP hydrolysis. GTP hydrolysis enables the GTPase domain of EF-Tu to extend away, releasing EF-Tu from tRNA. The 30S subunit then locks cognate tRNA in the decoding centre and rotates, enabling the tRNA to bypass 50S protrusions during accommodation into the peptidyl transferase centre. By contrast, the decoding centre fails to lock near-cognate tRNA, enabling the dissociation of near-cognate tRNA both during initial selection (before GTP hydrolysis) and proofreading (after GTP hydrolysis). These findings reveal structural similarity between ribosomes in initial selection states5,6 and in proofreading states, which together govern the efficient rejection of incorrect tRNA.

• MeSH
• elektronová kryomikroskopie * MeSH
• elongační faktor Tu chemie   metabolismus   ultrastruktura   MeSH
• Escherichia coli MeSH
• GTP-fosfohydrolasy metabolismus   MeSH
• guanosindifosfát chemie   metabolismus   MeSH
• guanosintrifosfát chemie   metabolismus   MeSH
• hydrolýza MeSH
• messenger RNA genetika   metabolismus   MeSH
• molekulární modely MeSH
• ribozomy chemie   metabolismus   ultrastruktura   MeSH
• RNA transferová chemie   genetika   metabolismus   ultrastruktura   MeSH
• rotace MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• elongační faktor Tu MeSH
• GTP-fosfohydrolasy MeSH
• guanosindifosfát MeSH
• guanosintrifosfát MeSH
• messenger RNA MeSH
• RNA transferová MeSH

During translation termination in bacteria, the release factors RF1 and RF2 are recycled from the ribosome by RF3. While high-resolution structures of the individual termination factors on the ribosome exist, direct structural insight into how RF3 mediates dissociation of the decoding RFs has been lacking. Here we have used the Apidaecin 137 peptide to trap RF1 together with RF3 on the ribosome and visualize an ensemble of termination intermediates using cryo-electron microscopy. Binding of RF3 to the ribosome induces small subunit (SSU) rotation and swivelling of the head, yielding intermediate states with shifted P-site tRNAs and RF1 conformations. RF3 does not directly eject RF1 from the ribosome, but rather induces full rotation of the SSU that indirectly dislodges RF1 from its binding site. SSU rotation is coupled to the accommodation of the GTPase domain of RF3 on the large subunit (LSU), thereby promoting GTP hydrolysis and dissociation of RF3 from the ribosome.

• MeSH
• elektronová kryomikroskopie MeSH
• Escherichia coli genetika   metabolismus   MeSH
• GTP-fosfohydrolasy metabolismus   MeSH
• kationické antimikrobiální peptidy farmakologie   MeSH
• konformace proteinů MeSH
• peptidy - faktory ukončení metabolismus   MeSH
• proteiny z Escherichia coli metabolismus   MeSH
• proteosyntéza účinky léků   MeSH
• ribozomální proteiny metabolismus   MeSH
• ribozomy metabolismus   MeSH
• RNA transferová metabolismus   MeSH
• simulace molekulového dockingu MeSH
• terminace translace peptidového řetězce MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• velké podjednotky ribozomu bakteriální metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• apidaecin MeSH Prohlížeč
• GTP-fosfohydrolasy MeSH
• kationické antimikrobiální peptidy MeSH
• peptidy - faktory ukončení MeSH
• prfA protein, E coli MeSH Prohlížeč
• prfC protein, E coli MeSH Prohlížeč
• proteiny z Escherichia coli MeSH
• ribozomální proteiny MeSH
• RNA transferová MeSH