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The key residue responsible for the red shift of bioluminescence spectra of light-sensitive Ca2+-regulated photoproteins of ctenophores
Abstract Isoforms of some ctenophore photoproteins show different maxima of bioluminescence spectra— the ones of mnemiopsin and bolinopsin have λmax at 490 and 500 nm, while λmax for velamin isoforms are at 500 and 508 nm. The reasons for the fact have not yet been established. Here we report on the construction and characterization of a set of mutants of berovin from ctenophore Beroe abyssicola with a substitution of Ala in position 106, which was selected for mutagenesis based on the comparison of the amino acid sequences of ctenophore photoproteins and the spatial structure model of berovin, to the residues with different properties of their side chains. The appearance of only Ser in this position, and its OH group in particular, is demonstrated to result in a green light emission. Moreover, we propose a plausible mechanism of bioluminescence spectrum shift towards longer wavelengths and the function of certain residues situated near OH group of the 6-(p-hydroxy)-phenyl substituent of coelenterazine in this process. We also conclude that the suggested mechanism of emitter formation is valid for other ctenophore photoproteins as well.
Research on the salt disease and deterioration simulation of hui-zhou corridor bridge(an-fu bridge) in China
Hybrid golden Jackal and moth flame optimization algorithm based coverage path planning in heterogeneous UAV networks
Learned saccade readiness varies with fluctuations in sustained attention
Abstract Both the focus of sustained attention and an individual’s readiness to shift attention among spatial locations fluctuate over time. However, the interaction of these ongoing changes in attentional states remains unknown. In the current study, participants completed a modified gradual continuous performance task during which they monitored one of two lateralized streams of black and white images for the appearance of frequent target stimuli, withholding responses to foils. Periodically, a visual cue signaled participants to either maintain fixation at the current stream or to make a saccade to the opposing stream, and participants made a parity categorization for a digit appearing at the cued location. Trial-by-trial variation in pupil size, an indicator of arousal, accounted for both fluctuations in sustained attention and shift readiness but fluctuations in sustained attention were not associated with general modulations of shift readiness. Furthermore, we manipulated the frequency of gaze shift cues over time and observed that unexpected shift cues were most disruptive when participants lacked sustained focus, yielding a greater cost in saccade latencies than when the efficacy of sustained attention was high. Our results suggest that ongoing changes in sustained attention occur independently from gaze shifting readiness but carry consequences for learned saccade preparation.
Corneal higher-order aberrations as key predictive indicators of axial elongation in myopic children with orthokeratology: a single-center prospective cohort study
Abstract This prospective study aimed to investigate changes in corneal higher-order aberrations (HOAs) in myopic children using orthokeratology (ortho-k) lenses and their relationship with myopia progression. A total of 112 children aged 8–13 years were divided into group A (axial elongation ≤ 0.1 mm/y with ortho-k) and group B (axial elongation > 0.1 mm/y with ortho-k). At baseline, 1, 6, and 12 months following the initiation of lens wear, HOAs and corneal peripheral defocus were evaluated. Ninety-three patients completed the 1-year follow-up. The mean axial elongation was − 0.07 ± 0.15 mm/y in group A, versus 0.32 ± 0.17 mm/y in group B. No statistical differences were observed in HOAs and corneal peripheral defocus at 1, 6, and 12 months (F = 0.653, 0.878; P > 0.05). Multivariate linear regression showed axial elongation was negatively correlated with ∆HOAs, peripheral defocus, and ∆horizontal coma (standardized beta=-0.331, -0.318, -0.209; P = 0.006, 0.001, 0.010, respectively) and positively correlated with the treatment zone diameter (standardized beta = 0.261, P = 0.003). Multivariate logistic regression identified ∆HOAs, peripheral defocus, ∆horizontal coma, and treatment zone as key factors distinguishing group A from group B (OR = 0.009, 0.455, 0.123, 12.172; P = 0.036, 0.003, 0.032, 0.019, respectively). The ROC curve for ∆HOAs had an area of 0.803 with a cut-off value of 0.834 μm. The ∆HOAs were more effective independent predictors of axial elongation than corneal peripheral defocus in children using ortho-k lenses. The ∆HOAs greater than 0.834 μm may lead to axial elongation ≤ 0.1 mm/y. These findings can be beneficial to fitting and optimizing ortho-k lenses.
Flecainide mediated sodium channel blockade enhances blood brain barrier integrity and promotes neuroprotection in neuroinflammation
Abstract Multiple Sclerosis (MS), an autoimmune disorder, is characterized by severe neuroinflammation, leading to demyelination and neuronal damage in the CNS, resulting in significant clinical impairment. MS progression involves complex pathological processes like immune cell invasion and cytokine-mediated recruitment to the CNS. Experimental autoimmune encephalomyelitis (EAE), widely used as a model for MS, despite its translational limitations, has been crucial for identifying effective treatments. Recent studies have shown that sodium channel (NaV) blockers and monoamine oxidase- (MAO) B inhibitors can alleviate symptoms of EAE and optic neuritis (ON), but their mode of action remains partially unclear. To evaluate the effects and understand the action mechanism of NaV blockers and MAO-B inhibitors (rasagiline, safinamide, flecainide and phenytoin) in neurological conditions, various techniques were used, including optical coherence tomography (OCT), optomotor response measurement (OMR), flow cytometry, histological evaluations, Evans blue assay, blood–brain barrier (BBB) permeability assay, western blot, proliferations assay, and gene expression analyses. The study found that the primary therapeutic effect comes from inhibiting the NaV 1.5 sodium channel, not MAO-B inhibition. Flecainide, a NaV 1.5 channel blocker, significantly reduced EAE disability scores, mitigated neurodegeneration, preserved visual function, and restricted immune cell migration into the CNS. Importantly, blocking the NaV 1.5 channel had an effect on the BBB, limiting lymphocyte entry into the CNS. This research highlights sodium channel blockers’ potential in treating EAE. The findings demonstrate induced neuroprotection and reduced disease progression, suggesting a novel therapeutic approach. Crucially, it reveals for the first time that NaV 1.5 channel blockade leads to neuroprotection primarily by affecting the BBB, a key factor in controlling immune cell migration, thus addressing a critical aspect of neuroinflammation.
An improved multi-strategy equilibrium optimizer for surface marine vehicle path planning
SRCIN1 promotes thyroid carcinoma growth by activating Wnt signaling pathway
Biomagnification and potential health effects of per- and polyfluoroalkyl substances (PFAS) in a terrestrial food web
Abstract Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants with bioaccumulative, biomagnifying and toxic potential, and largely unknown fate and health effects in terrestrial wildlife. In a contaminated area, we studied PFAS in a terrestrial food web including soil, mushrooms, berries, and wild-living herbivores (bank vole and two ungulate species) and a specialized predator (Tengmalm’s owl). In addition, in voles, we studied potential PFAS-induced liver damage and infection with a zoonotic pathogen. Concentrations of PFAS in vole livers were among the highest reported in terrestrial wildlife. Results suggest biomagnification of PFAS from soil, mushrooms, and berries to bank voles, from mushrooms to ungulates and from voles to the owl. Most vole livers showed diffuse cytoplasmic granulation, ranging from mild to severe, as well as mild and variable hepatocellular hypertrophy. We found high prevalence of Orthohantavirus puumalaense infection in bank voles, highlighting the possibility of PFAS-induced infection susceptibility. Our study supports that terrestrial wildlife magnifies PFAS from the environment and highlights largely unexplored yet worrying effects on wildlife health.
A novel residual network based on multidimensional attention and pinwheel convolution for brain tumor classification
Adaptive changes in the intestinal microbiota of giant pandas following reintroduction
Pollution indices of brackish water and sediments of major mangrove sites along Arabian Sea coast of Pakistan
Detection of GNSS spoofed signals based on the weighted moving average bias correction method
Repeated theta burst stimulation of the right ventrolateral prefrontal cortex reveals strong habituation in the context of stress and rumination
Abstract Prefrontal hypoactivation under stress has been consistently observed in individuals with high trait rumination and in patients with depression. However, no study has yet investigated the mechanisms of modulating activity of the Ventrolateral Prefrontal Cortex (VLPFC) by using excitatory and inhibitory Theta Burst Stimulation (TBS) in this context. To address this, we recruited 89 healthy participants (44 low trait ruminators and 45 high trait ruminators) who attended two lab sessions, each including stress induction via the Trier Social Stress Test (TSST). Participants received either excitatory intermittent TBS (iTBS) or inhibitory continuous TBS (cTBS). One session involved active TBS, while the other used sham TBS (sTBS), with the order randomized and balanced across stimulation conditions and groups. In high ruminators, we observed a significant impact of iTBS in the hypothesized direction when considering cortical oxygenation in the right VLPFC. We found higher subjective stress following iTBS and cTBS compared to sTBS during recovery of the TSST but only at the first appointment. No stimulation-dependent effects were found for other measures (state rumination, positive and negative affect, and heart rates). In our discussion, we draw conclusions concerning repeated-measures designs in TBS-studies.
Aging associated immunosenescence in rheumatoid arthritis identified by machine learning and single cell profiling
Characterization of novel Annona reticulata fiber as a potential reinforcement for composite applications
Abstract With the rising demand for sustainable and environmentally friendly materials, there is growing interest in alternative natural fibers for potential biocomposite applications. This study introduces a novel source of lignocellulosic fibers derived from the bark of Annona reticulata L., an abundant and underutilized bioresource. This novel fiber aims to meet the growing demand for eco-conscious textiles and biocomposite materials by preserving biodegradability and minimizing environmental impact. The fibers were extracted using a simple, chemical-free, short-duration water retting process, followed by drying. The dried fibers were characterized via chemical composition analysis, FTIR spectroscopy, density measurement, XRD, thermal analysis, morphological examination, and tensile testing. It was revealed that the fiber contains 56.26, 17.56, and 16.74% cellulose, hemicellulose, and lignin, respectively, while the density was found 1.33 g/cm3. XRD analysis indicates a crystalline index of 65% and a crystalline size of 3.34 nm, suggesting a moderately ordered cellulose structure. Thermogravimetric analysis confirmed thermal stability up to 258 °C, with maximum degradation occurring at 373 °C. FTIR analysis confirmed the presence of characteristic functional groups, including O–H stretching at 3309 cm⁻¹ and C–H stretching at 2928 cm⁻¹ in cellulose, as well as C = C stretching at 1514 cm⁻¹ in lignin, typical of lignocellulosic fibers. SEM imaging further revealed a fibrillar and bundled microstructure. Tensile testing showed an average tensile strength of 327 MPa and a Young’s modulus of 4.3 GPa, supporting the potential of Annona reticulata fibers for load-bearing applications. The findings of this study are comparable to those of commonly employed and some other new lignocellulosic fibers exhibited the potential of Annona reticulata for bicomposite applications.