Functional study
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This study explores the structural and electronic factors affecting the absorption spectra of 5-carboxy-tetramethylrhodamine (TAMRA) in water, a widely used fluorophore in imaging and molecular labeling in biophysical studies. Through molecular dynamics (MD) simulations and density functional theory (DFT) calculations, we examine TAMRA UV absorption spectra together with TAMRA-labeled peptides (Arg9, Arg4, Lys9). We found that DFT calculations with different functionals underestimate TAMRA maximum UV absorption peak by ~100 nm, resulting in the maximum at ca. 450 nm instead of the experimental value of ca. 550 nm. However, incorporating MD simulation snapshots of TAMRA in water, the UV maximum peak shifts and is in close agreement with the experimental results due to the rotation of TAMRA N(CH3)2 groups, effectively captured in MD simulations. The method is used to estimate the UV absorption spectra of TAMRA-labeled peptides, matching experimental values.
- Klíčová slova
- UV absorption spectra, fluorescent probes, molecular dynamics simulations, time‐dependent density functional theory,
- MeSH
- fluorescenční barviva * chemie MeSH
- peptidy * chemie MeSH
- rhodaminy * chemie MeSH
- simulace molekulární dynamiky * MeSH
- spektrofotometrie ultrafialová MeSH
- teorie funkcionálu hustoty * MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- fluorescenční barviva * MeSH
- peptidy * MeSH
- rhodaminy * MeSH
- tetramethylrhodamine MeSH Prohlížeč
OBJECTIVE: Pathophysiology explanations for functional movement disorders often assume a role for emotional hyperarousal. Pupillometry is a validated method for evaluation of emotional arousal by detecting changes in pupil size in response to emotional stimuli. In a case-control study design, we aimed to study objective and subjective emotional arousal using pupillometry and affective ratings. To assess attentional engagement by affective stimuli, we used videooculographic tracking of eye movement patterns (scanpath). METHODS: Twenty-five female patients with functional movement disorders (mean age: 40.9 [SD 12.7] years) and 23 age matched healthy female controls participated in the study. Using infrared high-resolution eye-tracker, both pupil size and eye movement pattern in response to emotionally charged erotic, adventure, threat, victim, and neutral pictures were recorded along with subjective ratings of emotional valence and arousal of the presented pictures. RESULTS: A between-group comparison showed significantly smaller pupil dilation to adventure stimuli compared to neutral stimuli in patients compared to controls (P < 0.004, bootstrap, uncorr., adj. η2 = 0.00). No significant difference in pupillary response to other stimuli and scanpath parameters was found between the groups. Patients rated significantly lower emotional arousal to erotic pictures than controls (P < 0.001, bootstrap, uncorr., adj. η2 = 0.09). CONCLUSION: This study did not find evidence of autonomous or subjective emotional hyperarousal. The mismatch between objective autonomic measures and subjective arousal ratings in patients is of pathophysiological interest and in line with recent findings of impaired interoception in functional movement disorders.
- Klíčová slova
- Affective ratings, Conversion disorder, Emotional arousal, Motor functional neurological disorder, Pupillometry, Scanpath,
- MeSH
- arousal * fyziologie MeSH
- dospělí MeSH
- emoce fyziologie MeSH
- konverzní poruchy * MeSH
- lidé MeSH
- pozornost MeSH
- studie případů a kontrol MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Brain imaging studies in complex regional pain syndrome (CRPS) have found mixed evidence for functional and structural changes in CRPS. In this cross-sectional study, we evaluated two patient cohorts from different centers and examined functional connectivity (rsFC) in 51 CRPS patients and 50 matched controls. rsFC was compared in predefined ROI pairs, but also in non-hypothesis driven analyses. Resting state (rs)fMRI changes in default mode network (DMN) and the degree rank order disruption index (kD) were additionally evaluated. Finally, imaging parameters were correlated with clinical severity and somatosensory function. Among predefined pairs, we found only weakly to moderately lower functional connectivity between the right nucleus accumbens and bilateral ventromedial prefrontal cortex in the infra-slow oscillations (ISO) band. The unconstrained ROI-to-ROI analysis revealed lower rsFC between the periaqueductal gray matter (PAG) and left anterior insula, and higher rsFC between the right sensorimotor thalamus and nucleus accumbens. In the correlation analysis, pain was positively associated with insulo-prefrontal rsFC, whereas sensorimotor thalamo-cortical rsFC was positively associated with tactile spatial resolution of the affected side. In contrast to previous reports, we found no group differences for kD or rsFC in the DMN, but detected overall lower data quality in patients. In summary, while some of the previous results were not replicated despite the larger sample size, novel findings from two independent cohorts point to potential down-regulated antinociceptive modulation by the PAG and increased connectivity within the reward system as pathophysiological mechanisms in CRPS. However, in light of the detected systematic differences in data quality between patients and healthy subjects, validity of rsFC abnormalities in CRPS should be carefully scrutinized in future replication studies.
- Klíčová slova
- Biomarker, CRPS, Functional connectivity, Neuropathic pain, Resting-state fMRI,
- MeSH
- default mode network diagnostické zobrazování patofyziologie MeSH
- dospělí MeSH
- komplexní regionální syndromy bolesti * patofyziologie diagnostické zobrazování MeSH
- konektom metody MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie * MeSH
- mozek patofyziologie diagnostické zobrazování MeSH
- nervová síť patofyziologie diagnostické zobrazování MeSH
- průřezové studie 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
OBJECTIVES: This study aimed to investigate the associations between radiographic damage, serum biomarkers, and clinical assessments in Czech patients with hand osteoarthritis (HOA) over a five-year follow-up period. METHODS: The study cohort comprised 129 patients diagnosed with HOA, including 72 patients with an erosive subtype and 57 patients with a non-erosive subtype. Radiographs were evaluated using the Kallman scoring system by two independent readers. Blood samples were analysed for markers of dyslipidaemia, bone metabolism, and inflammation. Clinical assessments focused on symptom severity and functional impairment. We employed generalised additive modelling (GAM) to analyse the associations between the Kallman score, serum biomarkers and clinical outcomes. RESULTS: The Kallman score was consistently higher in the erosive subtype compared to the non-erosive subtype across all time points and demonstrated a positive correlation with age in both groups. We demonstrated significant positive associations between radiographic progression and erythrocyte sedimentation rate across both HOA subtypes. Additionally, positive associations with the number of swollen joints and health assessment questionnaire scores were observed in all HOA patients, particularly in those with non-erosive subtypes. In contrast, markers of dyslipidaemia (e.g. LDL‑c or atherogenic index) were negatively associated with radiographic progression. No biomarker reliably differentiated between the erosive and non-erosive subtypes. CONCLUSIONS: Our longitudinal study revealed a significant association between systemic/local inflammation, dyslipidaemia, functional impairment and structural progression in HOA. However, these findings warrant further validation through additional studies to confirm these associations.
- MeSH
- biologické markery krev MeSH
- časové faktory MeSH
- dyslipidemie * krev diagnóza MeSH
- funkční status MeSH
- klouby ruky * diagnostické zobrazování patofyziologie MeSH
- krevní sedimentace MeSH
- lidé středního věku MeSH
- lidé MeSH
- longitudinální studie MeSH
- mediátory zánětu * krev MeSH
- osteoartróza * diagnostické zobrazování krev patofyziologie MeSH
- posuzování pracovní neschopnosti MeSH
- prediktivní hodnota testů MeSH
- progrese nemoci MeSH
- radiografie MeSH
- senioři MeSH
- stupeň závažnosti nemoci MeSH
- zánět * krev MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- biologické markery MeSH
- mediátory zánětu * MeSH
OBJECTIVE: Our objective was to assess cognitive functioning across multiple cognitive domains using a standardised neuropsychological battery in patients with motor functional neurological disorders (mFND). METHODS: Thirty patients with clinically established mFND and 30 age-, sex- and education-matched control subjects underwent a thorough neuropsychological assessment evaluating (1) attention including processing speed, (2) executive functions including working memory, (3) short-term memory, (4) speech and language and (5) visuospatial functions. Performance validity tests (PVT) and self-report measures of depression, anxiety and cognitive complaints were included in the assessment. Only patients with valid test performance were included in the analysis. RESULTS: Three patients scored below the cut-off scores in PVT. Patients performed significantly worse than controls in the following areas: (1) the attention domain which included a slow processing speed (p = 0.005, Cohen's d = 0.89), (2) executive functions (p = 0.01, Cohen's d = 0.88) and (3) speech and language domains (p = 0.025, Cohen's d = 0.77). Patients with mFND showed greater intra-individual variability in cognitive performance (p = 0.005, Cohen's d = 0.94). Cognitive impairments were independent of depressive symptoms, which were higher in mFND patients. CONCLUSION: This study revealed both subjective and objective cognitive impairment in patients with mFND. The neuropsychological profile in mFND was characterised primarily by attentional impairment including a slow processing speed and a high intra-individual variability in cognitive performance. Cognitive impairment was associated with a valid test performance, highlighting that the deficits observed were not likely to be explained by a lack of effort in the patient group. Attention is considered to play a key role in mFND pathophysiology, and the results suggest that such impairments are objectively measurable.
- Klíčová slova
- Attention, Cognitive functions, Motor functional neurological disorders, Neuropsychological profile, Performance validity,
- MeSH
- exekutivní funkce fyziologie MeSH
- kognice fyziologie MeSH
- kognitivní dysfunkce * komplikace etiologie MeSH
- kognitivní poruchy * diagnóza etiologie MeSH
- konverzní poruchy * MeSH
- lidé MeSH
- neuropsychologické testy MeSH
- pozornost fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Our ability to process complex social cues presented by faces improves during adolescence. Using multivariate analyses of neuroimaging data collected longitudinally from a sample of 38 adolescents (17 males) when they were 10, 11.5, 13 and 15 years old, we tested the possibility that there exists parallel variations in the structural and functional development of neural systems supporting face processing. By combining measures of task-related functional connectivity and brain morphology, we reveal that both the structural covariance and functional connectivity among 'distal' nodes of the face-processing network engaged by ambiguous faces increase during this age range. Furthermore, we show that the trajectory of increasing functional connectivity between the distal nodes occurs in tandem with the development of their structural covariance. This demonstrates a tight coupling between functional and structural maturation within the face-processing network. Finally, we demonstrate that increased functional connectivity is associated with age-related improvements of face-processing performance, particularly in females. We suggest that our findings reflect greater integration among distal elements of the neural systems supporting the processing of facial expressions. This, in turn, might facilitate an enhanced extraction of social information from faces during a time when greater importance is placed on social interactions.
- Klíčová slova
- adolescence, development, face processing, functional connectivity, structural covariance,
- MeSH
- dítě MeSH
- interpersonální vztahy MeSH
- lidé MeSH
- longitudinální studie MeSH
- magnetická rezonanční tomografie * MeSH
- mapování mozku MeSH
- mladiství MeSH
- mozek fyziologie MeSH
- nervová síť fyziologie MeSH
- obličej * MeSH
- podněty MeSH
- rozpoznávání obrazu fyziologie MeSH
- sexuální faktory MeSH
- věkové faktory MeSH
- výraz obličeje * MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: Our study aimed at exploring structural and functional differences in the brain during higher cognitive processing between middle-aged hypertensive patients and controls matched for sex, age and years of education. METHODS: Two groups of 20 patients took part in MRI examinations. This article reports the results of functional MRI during a Stroop color interference task and structural evaluations based on a modified Fazekas scale. RESULTS: No intergroup differences were found in regards to the severity of white matter lesions (Mann-Whitney U test = 150.5, P > 0.1), nor from the task performance in the scanner (t(35) = 0.2, P > 0.1). However, brain activation patterns between patients and controls varied. Hypertensive patients involved significantly more cerebral areas during the processing, regardless of the task difficulty. Differences were found in 26 diverse regions of both primary and associative cortices (with a peak voxel located in the cuneus, Z = 6.94, P < 0.05 family-wise error corrected at voxel level). CONCLUSION: Our findings provide an insight into the brain mechanisms related to essential hypertension and suggest a functional reorganization (neuroplasticity) early in the course of the disease.
- MeSH
- dospělí MeSH
- hypertenze komplikace patofyziologie MeSH
- kognitivní dysfunkce diagnostické zobrazování etiologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- mozek diagnostické zobrazování patologie patofyziologie MeSH
- neuropsychologické testy MeSH
- senioři MeSH
- studie případů a kontrol 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: Evidence suggests that brain-computer interface (BCI)-based rehabilitation strategies show promise in overcoming the limited recovery potential in the chronic phase of stroke. However, the specific mechanisms driving motor function improvements are not fully understood. OBJECTIVE: We aimed at elucidating the potential functional brain connectivity changes induced by BCI training in participants with chronic stroke. METHODS: A longitudinal crossover design was employed with two groups of participants over the span of 4 weeks to allow for within-subject (n = 21) and cross-group comparisons. Group 1 (n = 11) underwent a 6-day motor imagery-based BCI training during the second week, whereas Group 2 (n = 10) received the same training during the third week. Before and after each week, both groups underwent resting state functional MRI scans (4 for Group 1 and 5 for Group 2) to establish a baseline and monitor the effects of BCI training. RESULTS: Following BCI training, an increased functional connectivity was observed between the medial prefrontal cortex of the default mode network (DMN) and motor-related areas, including the premotor cortex, superior parietal cortex, SMA, and precuneus. Moreover, these changes were correlated with the increased motor function as confirmed with upper-extremity Fugl-Meyer assessment scores, measured before and after the training. CONCLUSIONS: Our findings suggest that BCI training can enhance brain connectivity, underlying the observed improvements in motor function. They provide a basis for developing novel rehabilitation approaches using non-invasive brain stimulation for targeting functionally relevant brain regions, thereby augmenting BCI-induced neuroplasticity and enhancing motor recovery.
- Klíčová slova
- Brain-computer interface, Default mode network, Functional Connectivity, Neuroplasticity, Resting-state fMRI, Stroke,
- MeSH
- cévní mozková příhoda * patofyziologie diagnostické zobrazování MeSH
- chronická nemoc MeSH
- default mode network * patofyziologie diagnostické zobrazování MeSH
- dospělí MeSH
- klinické křížové studie MeSH
- lidé středního věku MeSH
- lidé MeSH
- longitudinální studie MeSH
- magnetická rezonanční tomografie MeSH
- mozek * patofyziologie diagnostické zobrazování MeSH
- nervová síť * patofyziologie diagnostické zobrazování MeSH
- rehabilitace po cévní mozkové příhodě * metody MeSH
- rozhraní mozek-počítač * MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
We have performed a hierarchical ab initio benchmark and DFT performance study of D2 Ch•••A- chalcogen bonds (Ch = S, Se; D, A = F, Cl). The ab initio benchmark study is based on a series of ZORA-relativistic quantum chemical methods [HF, MP2, CCSD, CCSD(T)], and all-electron relativistically contracted variants of Karlsruhe basis sets (ZORA-def2-SVP, ZORA-def2-TZVPP, ZORA-def2-QZVPP) with and without diffuse functions. The highest-level ZORA-CCSD(T)/ma-ZORA-def2-QZVPP counterpoise-corrected complexation energies (ΔECPC ) are converged within 1.1-3.4 kcal mol-1 and 1.5-3.1 kcal mol-1 with respect to the method and basis set, respectively. Next, we used the ZORA-CCSD(T)/ma-ZORA-def2-QZVPP (ΔECPC ) as reference data for analyzing the performance of 13 different ZORA-relativistic DFT approaches in combination with the Slater-type QZ4P basis set. We find that the three-best performing functionals are M06-2X, B3LYP, and M06, with mean absolute errors (MAE) of 4.1, 4.2, and 4.3 kcal mol-1 , respectively. The MAE for BLYP-D3(BJ) and PBE amount to 8.5 and 9.3 kcal mol-1 , respectively.
- Klíčová slova
- benchmark study, chalcogen bonds, coupled-cluster, density functional calculations, noncovalent interactions,
- Publikační typ
- časopisecké články MeSH
In this study, a functionalized graphene oxide-cerium oxide nanocatalysts (FGCe) with varying graphene oxide (GO) contents were prepared using an in-situ reflux method. The prepared nanocatalysts showcased improvement in the crystallinity and BET surface area values with increasing GO contents. The efficacies of prepared catalysts were investigated towards oxidative pyrolysis of alkali lignin in an ethanol-water system. Among various nanocatalyst samples, the best lignin conversion (93 %) and bio-oil yield (86 %) were achieved using 50 mg FGCe nanocatalyst (0.5 wt% GO) at 423 K and 60 min. GC-MS and 1HNMR analyses were used to identify significant lignin conversion products, including 2-pentanone-4-hydroxy-4-methyl, 2-methoxyphenol, nonylcyclopropane, vanillin, apocynin, homovanollic acid, and benzoic acid. Kinetic studies revealed that the activation energy for lignin conversion was 24.36 kJ/mol at 423 K. Mechanistic investigations by density functional theory analysis revealed that the lignin breakdown occurred at oxygen bonds producing aromatic.
- Klíčová slova
- Alkali lignin, Cerium oxide, Density functional theory, Functionalized graphene oxide, Pyrolysis,
- MeSH
- alkálie * chemie MeSH
- cer * chemie MeSH
- dusík * chemie MeSH
- grafit * chemie MeSH
- katalýza MeSH
- kinetika MeSH
- lignin * chemie MeSH
- oleje rostlin MeSH
- oxidace-redukce MeSH
- plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
- polyfenoly MeSH
- pyrolýza * MeSH
- teorie funkcionálu hustoty MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- alkálie * MeSH
- Bio-Oil MeSH Prohlížeč
- cer * MeSH
- ceric oxide MeSH Prohlížeč
- dusík * MeSH
- grafit * MeSH
- graphene oxide MeSH Prohlížeč
- lignin * MeSH
- oleje rostlin MeSH
- polyfenoly MeSH