Associations between brain structures, cognition and dual-task performance in patients with mild cognitive impairment: A study based on voxel-based morphology.

BACKGROUND: This study aimed to explore the associations between brain structures, cognition, and motor control in participants with mild cognitive impairment (MCI), with a focus on dual-task performance. METHODS: Thirty MCI patients and thirty healthy controls were enrolled. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA). Structural magnetic resonance imaging data were analyzed using voxel-based morphometry (VBM) to calculate brain parenchyma volume and gray matter volume (GMV). Participants performed single- and dual-task Timed Up and Go (TUG) tests, and the correlations between significant GMV differences and task execution time was analyzed. RESULTS: MCI patients showed significantly lower MoCA scores, particularly in visuospatial/executive, attention, and delayed recall domains (p < 0.05). Dual-task TUG execution time was significantly increased in MCI patients (p < 0.05). The GMV in the right anterior lobe of the cerebellum and both insulae was positively correlated with visuospatial/executive scores (FDR-corrected, p < 0.05). The GMV of the right cerebellar anterior lobe and insula were significantly reduced in MCI patients (p < 0.05). The GMV of the right cerebellar anterior lobe was negatively correlated with dual-task execution time (r = -0.32, p = 0.012). CONCLUSION: Smaller GMV in the right anterior lobe of the cerebellum was associated with impaired dual-task performance, which may provide more evidence for the neural mechanisms of cognitive and motor function impairments in MCI.

Cortical Mechanisms Underlying Effects of Repetitive Peripheral Magnetic Stimulation on Dynamic and Static Postural Control in Patients with Chronic Non-Specific Low Back Pain: A Double-Blind Randomized Clinical Trial.

INTRODUCTION: Patients with chronic non-specific low back pain (CNLBP) often experience impaired postural control, contributing to pain recurrence. Although repetitive peripheral magnetic stimulation (rPMS) combined with core muscle training (CMT) could improve postural control, its neural mechanism remains unclear. This study aims to investigate the postural control-related cortical mechanism of the effect of rPMS on patients with CNLBP. METHODS: This unicentric, prospective, randomized, double-blind, controlled trial was conducted in a public hospital from May to December 2023. A total of 40 patients (27 females and 13 males, mean age 29.38 ± 7.72) with CNLBP were randomly assigned to either the rPMS group (real rPMS with CMT) or the sham-rPMS group (sham-rPMS with CMT) for 12 sessions over 4 weeks. The rPMS was applied to the lumbar paravertebral multifidus muscle on the painful side. Pain and disability were quantified using the visual analog scale (VAS) and Oswestry dysfunction index (ODI) pre- and post-intervention. Furthermore, the sway area and velocity of the center of pressure (COP) were measured using a force platform. The cortical activities in 6 regions of interest during 4 tasks (standing with eyes open/closed on a stable/unstable plane) were recorded by functional near-infrared spectroscopy (fNIRS) pre- and post-intervention. The repeated measure ANOVA was applied for statistical analysis. Spearman's correlation was used to determine the relationships between variables. RESULTS: After the intervention, the rPMS group showed decreased pain intensity (p = 0.001) and sway area (unstable eyes-closed task) (p = 0.046) compared to the sham-rPMS group. Additionally, the rPMS group exhibited increased activation in left primary motor cortex (M1) (p = 0.042) and reduced in left supplementary motor area (SMA) (p = 0.045), whereas the sham-rPMS group showed no significant changes. The increased activation of left M1 was negatively correlated to the reduction of pain intensity (r = - 0.537, p = 0.018) and sway area (r = - 0.500, p = 0.029) under the static balancing task. Furthermore, there was a positive correlation between sway velocity and VAS (r = 0.451, p = 0.046) post-rPMS intervention. CONCLUSION: Repetitive peripheral magnetic stimulation combined with core muscle training demonstrated better analgesic effects and postural control improvements, compared to sham-stimulation. This may be attributed to the increased activation of the left primary motor cortex. CLINICAL TRIAL REGISTRATION: The trial was registered on ClinicalTrials.gov (ChiCTR2300070943).

Relationship between Fear-Avoidance Beliefs and Reaction Time Changes Prior to and following Exercise-Induced Muscle Fatigue in Chronic Low Back Pain.

Background: Reaction time is a reliable indicator of the velocity and efficiency of neuromuscular control and may be associated with fear-avoidance beliefs. However, the effect of exercise-induced muscle fatigue on reaction time in chronic low back pain (cLBP) and its relationship with fear-avoidance beliefs remains poorly understood. Objectives: This study aimed to reveal the relationship between fear-avoidance beliefs and reaction time changes before and after exercise-induced muscle fatigue in cLBP. Methods: Twenty-five patients with cLBP were tested by the Biering-Sorensen test (BST) to induce exhaustive muscle fatigue. Total reaction time (TRT), premotor time (PMT), and electromechanical delay (EMD) of dominated deltoid muscle were recorded by surface electromyography during the arm-raising task with visual cues before and after muscle fatigue. The mean difference (MD) of TRT (MDTRT), PMT (MDPMT), and EMD (MDEMD) was calculated from the changes before and after muscle fatigue. Fear-avoidance beliefs questionnaire (FABQ) was applied to evaluate fear-avoidance beliefs before muscle fatigue. In addition, the duration time of BST was recorded for each subject. Results: TRT and PMT of dominated deltoid muscle were prolonged after exercise-induced muscle fatigue (Z = 3.511, p < 0.001; t = 3.431, p = 0.001), while there was no statistical difference in EMD (Z = 1.029, p = 0.304). Correlation analysis showed that both the MDTRT and MDPMT were positively correlated with FABQ (r = 0.418, p = 0.042; r = 0.422, p = 0.040). Conclusions: These findings suggested that we should pay attention to both muscle fatigue-induced reaction time delay in cLBP management and the possible psychological mechanism involved in it. Furthermore, this study implied that FABQ-based psychotherapy might serve as a potential approach for cLBP treatment by improving reaction time delay. This trial is registered with ChiCTR2300074348.

The gut microbiota and metabolite profiles are altered in patients with spinal cord injury.

BACKGROUND: Metabolites secreted by the gut microbiota may play an essential role in microbiota-gut-central nervous system crosstalk. In this study, we explored the changes occurring in the gut microbiota and their metabolites in patients with spinal cord injury (SCI) and analyzed the correlations among them. METHODS: The structure and composition of the gut microbiota derived from fecal samples collected from patients with SCI (n = 11) and matched control individuals (n = 10) were evaluated using 16S rRNA gene sequencing. Additionally, an untargeted metabolomics approach was used to compare the serum metabolite profiles of both groups. Meanwhile, the association among serum metabolites, the gut microbiota, and clinical parameters (including injury duration and neurological grade) was also analyzed. Finally, metabolites with the potential for use in the treatment of SCI were identified based on the differential metabolite abundance analysis. RESULTS: The composition of the gut microbiota was different between patients with SCI and healthy controls. At the genus level, compared with the control group, the abundance of UBA1819, Anaerostignum, Eggerthella, and Enterococcus was significantly increased in the SCI group, whereas that of Faecalibacterium, Blautia, Escherichia-Shigella, Agathobacter, Collinsella, Dorea, Ruminococcus, Fusicatenibacter, and Eubacterium was decreased. Forty-one named metabolites displayed significant differential abundance between SCI patients and healthy controls, including 18 that were upregulated and 23 that were downregulated. Correlation analysis further indicated that the variation in gut microbiota abundance was associated with changes in serum metabolite levels, suggesting that gut dysbiosis is an important cause of metabolic disorders in SCI. Finally, gut dysbiosis and serum metabolite dysregulation was found to be associated with injury duration and severity of motor dysfunction after SCI. CONCLUSIONS: We present a comprehensive landscape of the gut microbiota and metabolite profiles in patients with SCI and provide evidence that their interaction plays a role in the pathogenesis of SCI. Furthermore, our findings suggested that uridine, hypoxanthine, PC(18:2/0:0), and kojic acid may be important therapeutic targets for the treatment of this condition.

Electricity-Wettability Controlled Fast Transmission of Dopamine in Nanochannels.

Achieving fast transmembrane transmission of molecules in organisms is a challenging problem. Inspired by the transport of Dopmine (DA) in organisms, the DA transporter (DAT) binds to DA in a way that has a ring recognition (the recognition group is the tryptophan group). Herein, D-Tryptophan-pillar[5]arene (D-Trp-P5) functionalized conical nanochannel is constructed to achieve fast transmission of DA. The D-Trp-P5 functionalized nanochannel enables specific wettability recognition of DA molecules and has great cycle stability. With the controlling of voltage to wettability, the transport flux of DA is up to 499.73 nmol cm-2 h-1 at -6 V, 16.88 times higher than that under positive voltages. In response to these results, a high-throughput DA transport device based on controlled electricity-wettability is provided.

Chiral Transport in Nanochannel Based Artificial Drug Transporters.

The precise regulation of chiral drug transmembrane transport can be achieved through drug transporters in living organisms. However, implementing this process in vitro is still a formidable challenge due to the complexity of the biological systems that control drug enantiomeric transport. Herein, a facile and feasible strategy is employed to construct chiral L-tyrosine-modified nanochannels (L-Tyr nanochannels) based on polyethylene terephthalate film, which could enhance the chiral recognition of propranolol isomers (R-/S-PPL) for transmembrane transport. Moreover, conventional fluorescence spectroscopy, patch-clamp technology, laser scanning confocal microscopy, and picoammeter technology are employed to evaluate the performance of nanochannels. The results show that the L-Tyr nanochannel have better chiral selectivity for R-/S-PPL compared with the L-tryptophan (L-Trp) channel, and the chiral selectivity coefficient is improved by about 4.21-fold. Finally, a detailed theoretical analysis of the chirality selectivity mechanism is carried out. The findings would not only enrich the basic theory research related to chiral drug transmembrane transport, but also provide a new idea for constructing artificial channels to separate chiral drugs.

Effect of Progressive Postural Control Exercise Versus Core Stability Exercise in Young Adults with Chronic Low Back Pain: A Randomized Controlled Trial.

INTRODUCTION: This study aimed to investigate the effects of progressive postural control exercise (PPCE) vs core stability exercise (CSE) in patients with chronic low back pain (CLBP). METHODS: A total of 34 young-adult participants with CLBP were randomly assigned to two groups (the PPCE group and the CSE group). They received instructions for two different exercise training regimens persisting over 8 weeks. Before, after, and at 6 months after the intervention, the participants were evaluated on the basis of pain intensity (VAS), degree of dysfunction (ODI and RMDQ), contractility of transversus abdominis (TrA) and lumbar multifidus (MF), as well as the ability to control static posture. RESULTS: There was no significant difference between the results of the PPCE group and the CSE group. At the 6-month follow-up after the 8-week treatment, the scores of VAS, ODI, and RMDQ in the two groups decreased significantly compared to before (p < 0.05). The percentage change in thickness of bilateral TrA and left MF (p < 0.05) was elevated and the sway area of center of pressure during static stance tasks with eyes opened (p < 0.05) was decreased in both groups. CONCLUSION: In the short term, PPCE provides positive effects similar to those of core stability exercise in patients with CLBP. The effective mechanism of PPCE might be the consequence of neuromuscular plasticity and adaptation adjustments. PPCE enriches the choices of treatment for CLBP. CLINICAL TRIAL REGISTRATION: The trial was registered at www.chictr.org.cn , identifier ChiCTR2100043113.

Chronic low back pain (CLBP) is a widespread disorder with highly recurrent prevalence. As of now, the treatment effects are not satisfactory, leading to a search for novel therapies that might work better in patients with CLBP. This study comprehensively explored the effects of progressive postural control exercise, as compared to core stability exercise, on patients with CLBP. The outcomes included pain intensity, disability of daily life, contractility of trunk muscles, and postural control. The results of the study showed that the efficacy of exercises in patients in the experimental group was similar to that of the control group and both exercise treatments improved the pain intensity, the disability, the contractile function of trunk muscle, as well as postural control in patients with CLBP in the short term. The mechanism of the effects of progressive postural control exercise might be the consequence of "neuromuscular plasticity" and adaptation adjustments.

Supramolecular Biopharmaceutical Carriers Based on Host-Guest Interactions.

Traditional drugs have the disadvantages of poor permeability and low solubility, which makes the utilization of pesticides lower and brings many side effects. With the continuous development of supramolecular chemistry in recent years, it has also played an irreplaceable role in the field of pharmaceutical science. Supramolecular macrocycles, such as crown ethers, cyclodextrins, calixarenes, pillararenes and cucurbiturils, are potentially good candidates for drug carriers due to their biocompatibility, hydrophobic cavity and ease of derivatization. The encapsulation of drugs based on host-guest interaction has the advantage of being adjustable and reversible as well as improving the low availability of drugs. Here, the recent advances in methods and strategies for drug encapsulation and release based on supramolecular macrocycles with host-guest interactions have been systematically summarized, laying a bright foundation for the development of novel nanopesticide preparations in the future and pointing out future directions of novel biopesticide research.

Chiral Covalent Organic Framework Packed Nanochannel Membrane for Enantioseparation.

A nanochannel membrane has the prospect of large-scale separation. However, selectivity in enantioseparation is a challenge, due to the size difference between nanochannels and enantiomers. Here, we compartmented nanochannels by the in situ synthesis of a L-tyrosine functionalized covalent organic framework (L-Tyr-COF). The L-Tyr-COF decreased the pore size of channels to match with naproxen enantiomers (S/R-NPX) and improved the enantioselective gating. In contrast to the surface-functionalized nanochannels (L-Tyr channel), the L-Tyr-COF packed nanochannels (L-Tyr-COF channel) exhibited high enantioselectivity for S-NPX and realized the enantioseparation with the enantiomer excess value up to 94.2 %. The separation flux through the highly porous L-Tyr-COF channel was 1.33 mmol m-2 h-1 . This study provided a size-matching strategy and the chiral covalent organic framework packed nanochannel membrane to realize enantioseparation with high selectivity and flux.

Highly Chiral Selective Resolution in Pillar[6]arenes Functionalized Microchannel Membranes.

High flux microchannel membranes have the potential for large scale separations. However, it is prevented by poor enantioselectivity. Therefore, the development of a high-enantioselective microchannel membrane is of great importance for large scale chiral separations. In this work, chiral gold nanoparticles are incorporated into the microchannel membrane to astringe the large pores and improve the enantioselectivity. Here, the gold nanoparticles are functionalized by l-phenylalanine-derived pil-lararenes (l-Phe-P6@AuNPs) as the chiral receptor of R-phenylglycinol (R-PGC) over its enantiomer. This chiral Au NPs coated microchannel membrane (l-Phe-P6@AuNPs microchannel) shows a selectivity of 5.40 for R-PGC and a flux of 140.35 nmol·cm-2·h-1, where the enantioselectivity is improved, ensuring its flux. Compared with the enantioselectivity and flux of nanochannel membranes reported in literatures, the l-Phe-P6@AuNPs microchannel has the advantage for enantioselectivity and flux for chiral separation.

Highly enantioselective recognition of S-ibuprofen by a host-guest induced chiral nanochannel.

Chirality is an important property, especially for chiral drug enantiomers with huge differences in pharmacology and toxicity. Chiral recognition of drug enantiomers is the first step to understanding the physiological phenomenon and ensuring medical safety. To efficiently identify and isolate these chiral drugs, we prepared a nanochannel. Here, a chiral sensor was fabricated by introducing the host-guest system of pillar[5]arene (WAP5) and phenethylamine into solid-state nanochannels. The chiral guest R-phenethylamine (R-PEA) induced the chirality of the host-guest system and amplified the chiral selectivity for ibuprofen enantiomers in the host-guest-based nanochannels, which was significantly greater than that in the aqueous phase or the R-PEA modified nanochannels. This study provides a strategy to fabricate highly enantioselective nanosensors for chiral drugs.

Controlled release of drug molecules by pillararene-modified nanosystems.

Stimuli-responsive nanosystems have attracted the interest of researchers due to their intelligent function of controlled release regulated by a variety of external stimuli and have been applied in biomedical fields. Pillar[n]arenes with the advantages of a rigid structure, electron holes and easy functionalization are considered as excellent candidates for the construction of host-guest nanosystems. In recent years, many pillararene modified nanosystems have been reported in response to different stimuli. In this feature article, we summarize the advance of stimuli-responsive pillararene modified nanosystems for controlled release of drugs from the perspectives of decomposition release and gated release, focusing on the control principles of these nanosystems. We expect that this review can enlighten and guide investigators in the field of stimuli-responsive controlled release.

Photoresponsive Solid Nanochannels Membranes: Design and Applications.

Light stimuli have notable advantages over other environmental stimuli, such as more precise spatial and temporal regulation, and the ability to serve as an energy source to power the system. In nature, photoresponsive nanochannels are important components of organisms, with examples including the rhodopsin channels in optic nerve cells and photoresponsive protein channels in the photosynthesis system of plants. Inspired by biological channels, scientists have constructed various photoresponsive, smart solid-state nanochannels membranes for a range of applications. In this review, the methods and applications of photosensitive nanochannels membranes are summarized. The authors believe that this review will inspire researchers to further develop multifunctional artificial nanochannels for applications in the fields of biosensors, stimuli-responsive smart devices, and nanofluidic devices, among others.

Impaired static postural control correlates to the contraction ability of trunk muscle in young adults with chronic non-specific low back pain: A cross-sectional study.

INTRODUCTION: Patients with chronic non-specific low back pain (CNSLBP) were found with impaired postural control in previous studies. Since the trunk muscle take important efforts on core stability, the study aimed to examine the relationships of postural control during stance tasks and the contractility of trunk muscle in young adults with CNSLBP and without. METHODS: Healthy individuals (n = 25) and individuals with CNSLBP (n = 30) were included. The thickness of the bilateral transversus abdominis (TrA) and lumbar multifidus (MF) was measured during rest and maximal voluntary contraction, and the change percentages (TrA%, MF%) were calculated. Regarding postural control, COP path length and sway area during the stance tasks were measured thrice in each group. RESULTS: The bilateral TrA% of the CNSLBP group was less than that of the HC group (p < 0.05). The bilateral TrA% of the CNSLBP group was less than that of the HC group (p < 0.05). The bilateral MF% showed no significantly different(p > 0.05) between the two groups. Compared with healthy controls, CNSLBP patients resulted larger path length and sway area of COP during most of static stance tasks. During the EO task in the CNSLBP group, TrA% was found correlate to COP path length (p < 0.05); the right MF% was correlated with COP sway area (p < 0.05). No significant correlations appeared in the healthy controls (p > 0.05). CONCLUSIONS: Compared with healthy individuals, impaired postural control during static stance with eyes open in patients with CNSLBP was likely to be related to the poor contraction ability of bilateral transversus abdominis and correlated to the normal contraction ability of right lumbar multifidus.

Construction of A High-Flux Protein Transport Channel Inspired by the Nuclear Pore Complex.

Inspired by the nuclear pore complex (NPC), herein we have established a biomimetic high-flux protein delivery system via the ingenious introduction of pillar[5]arene-based host-guest system into one side of artificial hour-glass shaped nanochannel. With a transport flux of 660 lysozymes per minute, the system provides efficient high-flux protein transport at a rate which is significantly higher than that of an unmodified nanochannel and conventional bilateral symmetrical modified nanochannels. In view of these promising results, the use of artificial nanochannel to improve protein transport not only presents a new potential chemical model for biological research and better understanding of protein transport behavior in the living systems, but also provides a high-flux protein transporter device, which may have applications in the design of protein drug release systems, protein separation systems and microfluidics in the near future.

The Effect of Virtual Reality Training on Anticipatory Postural Adjustments in Patients with Chronic Nonspecific Low Back Pain: A Preliminary Study.

Objectives: This study is aimed at exploring the effects of virtual reality (VR) training on postural control, measured by anticipatory and compensatory postural adjustments (APAs and CPAs, respectively), in patients with chronic nonspecific low back pain (CNLBP) and the potential neuromuscular mechanism of VR training. Methods: Thirty-four patients were recruited and randomly assigned to the VR group (n = 11), the motor control exercise group (MCE, n = 12) and the control group (CG, n = 11). The VR group received VR training using Kinect Xbox 360 systems and magnetic therapy. Besides magnetic therapy, the participants in the MCE group performed real-time ultrasound-guided abdominal drawing-in maneuver (ADIM) and four-point kneeling exercise. The CG only received magnetic therapy. Surface muscle electromyography (sEMG) was used to record the muscle activities of transverse abdominis (TrA), multifidus (MF), lateral gastrocnemius (LG), and tibialis anterior (TA) during ball-hitting tasks. The muscle activation time and integrals of the electromyography activities (IEMGs) during the APA and CPA stages were calculated and used in the data analysis. The visual analogue scale (VAS) and Oswestry dysfunction index (ODI) scores were also recorded. Results: A significant interaction effect of time × group was observed on the activation time of TrA (p = 0.018) and MF (p = 0.037). The post-intervention activation time of the TrA was earlier in the VR group (p = 0.029). In contrast, the post-intervention activation time of the MF was significantly delayed in the VR group (p = 0.001). The IEMGs of TrA (p = 0.002) and TA (p = 0.007) during CPA1 significantly decreased only in the VR group after the intervention. The VAS scores of three group participants showed significant decreases after intervention (p < 0.001). Conclusions: Patients with CNLBP showed reciprocal muscle activation patterns of the TrA and MF muscles after VR training. VR training may be a potential intervention for enhancing the APAs of the patients with CNLBP.

Promoting the Spreading of Droplets on a Superhydrophobic Surface by Supramolecular Amphiphilic Complex-Based Host-Guest Chemistry.

The spreading of pesticide droplets on the surface of superhydrophobic plants is an important process, which can prevent the inadequate retention such as bouncing, splashing, and drifting, thereby improving the efficiency of pesticide utilization and reducing soil and groundwater pollution. Herein, we report an approach to fabricate a supramolecular amphiphilic system that significantly contributes to this issue. The hydrophilic amino-pillar[5]arene was synthesized, which could form vesicles with the hydrophobic long-chain guest. This host-guest complex decreased the surface tension, which greatly promotes the spreading of droplets. This study provides a new strategy for prolonging pesticide retention and reducing pesticide loss.

Recent advances in chiral discrimination on host-guest functionalized interfaces.

Chiral discrimination has gained much focus in supramolecular chemistry, since it is one of the fundamental processes in biological systems, enantiomeric separation and biochemical sensors. Though most of the biochemical processes can routinely recognize biological enantiomers, enantioselective identification of chiral molecules in artificial systems is currently one of the challenging topics in the field of chiral discrimination. Inaccuracy, low separation efficiency and expensive instrumentation were considered typical problems in artificial systems. Recently, chiral recognition on the interfaces has been widely used in the fields of electrochemical detection and biochemical sensing. For the moment, a series of macrocyclic host functionalized interfaces have been developed for use as chiral catalysts or for enantiomeric separation. Here, we have briefly exposited the most recent advances in the fabrication of supramolecular functionalized interfaces and their application for chiral recognition.

Enantioselective Antiport in Asymmetric Nanochannels.

Enantioselective sensing and separation are major challenges. Nanochannel technologies are energy-saving and efficient for membrane separation. Herein, inspired by biological antiporter proteins, artificial nanochannels with antiporter behavior were fabricated for chiral sensing and separation. Tyrosine enantiomers were incorporated into hourglass-shaped nanochannels via stepwise modifications to fabricating multiligand-modified asymmetric channels. Chiral distinction of naproxen enantiomers was amplified in the l-Tyr/d-Tyr channels, with an enantioselectivity coefficient of 524, which was over 100-fold that of one-ligand-modified nanochannels. Furthermore, transport experiments evidenced the spontaneous antiport of naproxen enantiomers in the l-Tyr/d-Tyr channels. The racemic naproxen sample was separated via the chiral antiport process, with an enantiomeric excess of 71.2%. Further analysis using electro-osmotic flow experiments and finite-element simulations confirmed that the asymmetric modified multiligand was key to achieving separation of the naproxen enantiomers. We expect these multiligand-modified asymmetric nanochannels to provide insight into mimicking biological antiporter systems and offer an approach to energy-efficient and robust enantiomer separation.