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1.
J Sep Sci ; 47(15): e2400140, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39108164

RÉSUMÉ

In this article, chiral covalent organic framework core-shell composite CCOF-TpPa-Py@SiO2 was facilely synthesized by induction at room temperature. The CCOF-TpPa-Py@SiO2 core-shell composite was used as a chiral stationary phase for the separation of the racemates by high-performance liquid chromatography, which exhibits good separation performance for chiral compounds including ketones, alcohols, esters, epoxides, carboxylic acids, amides, and amines. The effects of analyte injection mass on the enantioseparation were studied. The reproducibility and stability of the CCOF-TpPa-Py@SiO2 chiral column were explored. The intra-day (n = 5), inter-day (n = 5), and inter-column (n = 3) relative standard deviations for the migration times and resolution of benzoin were 0.32%-0.54%, 0.45%-0.61%, and 1.21%-1.53%, respectively. In addition, the chiral separation ability of the CCOF-TpPa-Py@SiO2 chiral column (column A) was compared with that of the MDI-ß-CD-Modified COF@SiO2 (column B) as well as a commercial chiral column (Chiralpak AD-H). The chiral recognition ability of column A is complementary to that of column B and AD-H column. The resolution mechanism of CCOF-TpPa-Py@SiO2 stationary phase towards chiral analyte was explored. Hence, the synthesis of CCOF-TpPa-Py@SiO2 core-shell composite by induction at room temperature as chiral stationary phases for chromatographic separation has important research potential and application prospects.

2.
J Neuroimmune Pharmacol ; 19(1): 38, 2024 Jul 27.
Article de Anglais | MEDLINE | ID: mdl-39066908

RÉSUMÉ

Repetitive exposure of innate immune cells to a subthreshold dosage of endotoxin components may modulate inflammatory responses. However, the regulatory mechanisms in the interactions between the central nervous system (CNS) and the immune system remain unclear. This study aimed to investigate the effects of lipopolysaccharide (LPS) preconditioning in repeated social defeat stress (RSDS)-induced abnormal immune responses and behavioral impairments. This study aimed to elucidate the mechanisms that underlie the protective effects of repeated administration of a subthreshold dose LPS on behavioral impairments using the RSDS paradigm. LPS preconditioning improved abnormal behaviors in RSDS-defeated mice, accompanied by decreased monoamine oxidases and increased glucocorticoid receptor expression in the hippocampus. In addition, pre-treated with LPS significantly decreased the recruited peripheral myeloid cells (CD11b+CD45hi), mainly circulating inflammatory monocytes (CD11b+CD45hiLy6ChiCCR2+) into the brain in response to RSDS challenge. Importantly, we found that LPS preconditioning exerts its protective properties by regulating lipocalin-2 (LCN2) expression in microglia, which subsequently induces expressions of chemokine CCL2 and pro-inflammatory cytokine. Subsequently, LPS-preconditioning lessened the resident microglia population (CD11b+CD45intCCL2+) in the brains of the RSDS-defeated mice. Moreover, RSDS-associated expressions of leukocytes (CD11b+CD45+CCR2+) and neutrophils (CD11b+CD45+Ly6G+) in the bone marrow, spleen, and blood were also attenuated by LPS-preconditioning. In particular, LPS preconditioning also promoted the expression of endogenous antioxidants and anti-inflammatory proteins in the hippocampus. Our results demonstrate that LPS preconditioning ameliorates lipocalin 2-associated microglial activation and aberrant immune response and promotes the expression of endogenous antioxidants and anti-inflammatory protein, thereby maintaining the homeostasis of pro-inflammation/anti-inflammation in both the brain and immune system, ultimately protecting the mice from RSDS-induced aberrant immune response and behavioral changes.


Sujet(s)
Lipopolysaccharides , Souris de lignée C57BL , Défaite sociale , Stress psychologique , Animaux , Lipopolysaccharides/toxicité , Souris , Mâle , Stress psychologique/immunologie , Microglie/effets des médicaments et des substances chimiques , Microglie/métabolisme , Microglie/immunologie , Comportement animal/effets des médicaments et des substances chimiques , Hippocampe/effets des médicaments et des substances chimiques , Hippocampe/métabolisme , Hippocampe/immunologie , Lipocaline-2/métabolisme
3.
Small ; : e2402798, 2024 Jul 14.
Article de Anglais | MEDLINE | ID: mdl-39004884

RÉSUMÉ

The properties of single molecules and molecular aggregates can differ dramatically, leading to a long-standing interest in mesoscale aggregation processes. Herein, a series of acid-base molecular complexes is developed by using a tetraphenylethylene-backboned fluorophore, and investigated the photophysical properties and photochemical activities at different aggregation length scales. This fluorophore, with two basic diethylamine groups and two acidic tetrazole groups, exhibits sparse solubility due to multivalent interactions that cause infinite aggregation. The addition of a third acid leads to the formation of fluorophore/acid complexes with good dispersibility and colloidal stability. This assembly process can be controlled by the use of different acids and their stoichiometry, resulting in aggregates ranging in size from a few to hundreds of nanometers. A crystalline structure is obtained to illustrate the complex properties of the acid-base network. Unlike the single molecule, these complexes show a trend of size-related properties for photoluminescence efficiency and photochemical activity. As the amount of acid added increases, the size of the complexes decreases, the aggregation effect of the complexes on fluorescence emission increases, and the rates of the oxidative photocyclization and photodecomposition slow down. This work may help to understand size-controlled molecular materials at the mesoscale for functional design.

4.
Langmuir ; 40(28): 14548-14554, 2024 Jul 16.
Article de Anglais | MEDLINE | ID: mdl-38963797

RÉSUMÉ

Aggregation-induced emission (AIE) has revolutionized solid-state fluorescence by overcoming the limitations of aggregation-caused quenching. While extensively studied in solutions, AIE's potential on solid surfaces remains largely unexplored, which can be fundamentally interesting and practically useful. In this work, we demonstrate the successful dispersion of tetraphenylethylene (TPE), one of the most classical AIE luminogens, on solid surfaces coated with silicone nanofilaments (SNF). The high surface area of SNF enables the uniform immobilization of TPE luminogens, replicating their dispersal behavior in solutions. Compared to unmodified surfaces, TPE dispersed on SNF-coated surfaces exhibits significantly enhanced fluorescence intensity. Moreover, a fascinating dynamic blue shift in TPE emission on SNF-coated surfaces is observed, with the velocity controllable by the surface group of SNF by up to 4 orders of magnitude, showing that TPE can be applied to the judgment of the nanoscale morphology and surface free energy of the solid surface. Owing to the superhydrophobicity and self-cleaning properties of SNF, the on-surface fluorescence can be sustained underwater and is resistant to dust contamination and rain erosion, with potential applications of information encryption presented. Our approach of uniformly dispersing AIE luminogens on nanomaterials with high surface areas provides a general methodology for creating on-surface fluorescence and saving the usage of expensive AIE luminogens in applications.

5.
Acad Radiol ; 2024 Jul 05.
Article de Anglais | MEDLINE | ID: mdl-38971660

RÉSUMÉ

RATIONALE AND OBJECTIVES: We explored the feasibility of using total tumor apparent diffusion coefficient (ttADC) histogram parameters to predict high-risk cytogenetic abnormalities (HRCA) in patients with multiple myeloma (MM) and compared the performance of an image prediction model based on these parameters with that of a combined prediction model based on these parameters and clinical indicators. METHODS: We retrospectively analyzed the parameters of the ttADC histogram based on whole-body diffusion-weighted images(WB-DWI) and clinical indicators in 92 patients with MM. The patients were divided into HRCA and non-HRCA groups according to the results of the fluorescence in situ hybridization. Logistic regression analysis was used to construct the image prediction and combined prediction models. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was used to evaluate the performance of the models to identify HRCA. The DeLong test was used to compare the AUC differences of each prediction model. RESULTS: Logistic regression analysis results revealed that the ttADC histogram parameter, ttADC entropy < 7.959 (OR: 39.167; 95% confidence interval [CI]: 3.891-394.208; P < 0.05), was an independent risk factor for HRCA. The image prediction model consisted of ttADC entropy and ttADC SD. The combined prediction model included ttADC entropy along with patient clinical indicators such as biological sex and M protein percentage. The AUCs of the image prediction and combined prediction models were 0.739 and 0.811, respectively (P < .05). The image prediction model showed a sensitivity of 73.9% and a specificity of 68.1%. The combined prediction model showed 82.6% sensitivity and 72.5% specificity. CONCLUSIONS: Using ttADC histogram parameters based on WB-DWI images to predict HRCA in patients with MM is feasible, and combining ttADC parameters with clinical indicators can achieve better predictive performance.

6.
Mikrochim Acta ; 191(8): 445, 2024 Jul 03.
Article de Anglais | MEDLINE | ID: mdl-38958767

RÉSUMÉ

A novel CCOF core-shell composite material (S)-DTP-COF@SiO2 was prepared via asymmetric catalytic and in situ growth strategy. The prepared (S)-DTP-COF@SiO2 was utilized as separation medium for HPLC enantioseparation using normal-phase and reversed-phase chromatographic modes, which displays excellent chiral separation performance for alcohols, esters, ketones, and epoxides, etc. Compared with chiral commercial chromatographic columns (Chiralpak AD-H and Chiralcel OD-H columns) and some previously reported chiral CCOF@SiO2 (CC-MP CCTF@SiO2 and MDI-ß-CD-modified COF@SiO2)-packed columns, there are 4, 3, 13, and 15 tested racemic compounds that could not be resolved on the Chiralpak AD-H column, Chiralcel OD-H column, CC-MP CCTF@SiO2 column, and MDI-ß-CD-modified COF@SiO2 column, respectively, which indicates that the resolution effect of (S)-DTP-COF@SiO2-packed column can be complementary to the other ones. The effects of the analyte mass, column temperature, and mobile phase composition on the enantiomeric separation were investigated. The chiral column exhibits good reproducibility after multiple consecutive injections. The RSDs (n = 5) of the peak area and retention time were less than 1.5% for repetitive separation of 2-methoxy-2-phenylethanol and 1-phenyl-1-pentanol. The chiral core-shell composite (S)-DTP-COF@SiO2 exhibited good enantiomeric separation performance, which not only demonstrates its potential as a novel CSP material in HPLC but also expands the range of applications for chiral COFs.

7.
Plant Physiol Biochem ; 212: 108783, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38824694

RÉSUMÉ

Cimicifuga dahurica (C. dahurica) is an important medicinal plant in the northern region of China. The best supplemental light environment helps plant growth, development, and metabolism. In this study, we used two-year-old seedlings as experimental materials. The white light as the control (CK). The different ratios of red (R) and blue (B) combined light were supplemented (T1, 2R: 1B, 255.37 µmol m-2·s-1; T2, 3R: 1B, 279.69 µmol m-2·s-1; T3, 7R: 1B, 211.16 µmol m-2·s-1). The growth characteristics, photosynthetic pigment content, photosynthesis and chlorophyll fluorescence parameters, and primary metabolite content were studied in seedlings. The results showed that: 1) The fresh weight from shoot, root, and total fresh weight were significantly (P < 0.05) increased under T2 and T3 treatment. 2) The contents of chlorophyll a (Chl a), chlorophyll b (Chl b), and total chlorophyll (Chl) were significantly (P < 0.05) increased under T2 treatment, and carotenoid (car) content was reduced. 3) The photochemical quenching (qP), the actual photosynthetic efficiency of PSII (Y(II)), and the photosynthetic electron transfer rate (ETR) from leaves were significantly (P < 0.05) increased under T1 treatment. The Net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci), and transpiration rate (Tr) were significantly (P < 0.05) increased under T2 and T3 treatments. 4) A total of 52 primary metabolites were detected in C. dahurica leaves. Compared with CK, 14, 15, and 18 differential metabolites were screened under T1, T2, and T3 treatments. In addition, D-xylose, D-glucose, glycerol, glycolic acid, and succinic acid were significantly (P < 0.05) accumulated under the T2 treatment, which could regulate the TCA cycle metabolism pathway. The correlation analysis suggested that plant growth was promoted by regulating the change of D-mannose content in galactinol metabolism and amino sugar and nucleotide sugar metabolism. In summary, the growth of C. dahurica was improved under T2 treatment.


Sujet(s)
Chlorophylle , Cimicifuga , Lumière , Photosynthèse , Chlorophylle/métabolisme , Cimicifuga/métabolisme , Plant/croissance et développement , Plant/métabolisme , Caroténoïdes/métabolisme , Feuilles de plante/métabolisme , Feuilles de plante/croissance et développement , Chlorophylle A/métabolisme
8.
Talanta ; 277: 126388, 2024 Sep 01.
Article de Anglais | MEDLINE | ID: mdl-38870759

RÉSUMÉ

Metal organic cages (MOCs), as an emerging discrete supramolecular compounds, have received widespread attention in separation, biomedicine, gas capture, catalysis, and molecular recognition due to their porosity, adjustability and stability. Herein, we present a new chiral MOC FeII4L4 coated capillary column prepared for gas chromatographic (GC) separation of different types of organic compounds, including n-alkanes, n-alcohols, alkylbenzenes, isomers, especially for racemic compounds. There are 20 different kinds of racemates (e.g., alcohols, ethers, epoxides, esters, alkenes, and aldehydes) were well resolved on the FeII4L4 chiral column and a maximum resolution value for 1-phenyl-1-propanol reaches 6.17. The FeII4L4 coated column exhibited high column efficiency (3100 plates m-1 for n-dodecane) and good enantiomeric resolution complementary to that of a commercial ß-DEX 120 column and the previously reported chiral MOC [Fe4L6] (ClO4)8 coated column. The relative standard deviation (RSDs) of the peak area and retention time of glycidol and nitrotoluene were below 1.2 %. This study reveals that chiral MOCs have good application prospects in chromatographic separation.

9.
Pharmacol Biochem Behav ; 241: 173794, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38834160

RÉSUMÉ

Psychological stress affects the neuroendocrine regulation, which modulates mental status and behaviors. Melatonin, a hormone synthesized primarily by the pineal gland, regulates many brain functions, including circadian rhythms, pain, sleep, and mood. Selective pharmacological melatonin agonist ramelteon has been clinically used to treat mood and sleep disorders. Posttraumatic stress disorder (PTSD) is a psychiatric condition associated with severe trauma; it is generally triggered by traumatic events, which lead to severe anxiety and uncontrollable trauma recall. We recently reported that repeated social defeat stress (RSDS) may induce robust anxiety-like behaviors and social avoidance in mice. In the present study, we investigated whether melatonin receptor activation by melatonin and ramelteon regulates RSDS-induced behavioral changes. Melatonin treatment improved social avoidance and anxiety-like behaviors in RSDS mice. Moreover, treatment of the non-selective MT1/MT2 receptor agonist, ramelteon, markedly ameliorated RSDS-induced social avoidance and anxiety-like behaviors. Moreover, activating melatonin receptors also balanced the expression of monoamine oxidases, glucocorticoid receptors, and endogenous antioxidants in the hippocampus. Taken together, our findings indicate that the activation of both melatonin and ramelteon regulates RSDS-induced anxiety-like behaviors and PTSD symptoms. The current study also showed that the regulatory effects of neuroendocrine mechanisms and cognitive behaviors on melatonin receptor activation in repeated social defeat stress.


Sujet(s)
Anxiété , Indènes , Mélatonine , Défaite sociale , Stress psychologique , Animaux , Indènes/pharmacologie , Souris , Mâle , Stress psychologique/métabolisme , Stress psychologique/traitement médicamenteux , Mélatonine/pharmacologie , Anxiété/traitement médicamenteux , Anxiété/psychologie , Comportement animal/effets des médicaments et des substances chimiques , Hippocampe/effets des médicaments et des substances chimiques , Hippocampe/métabolisme , Récepteurs aux glucocorticoïdes/métabolisme , Récepteurs aux glucocorticoïdes/agonistes , Récepteur de la mélatonine de type MT1/agonistes , Récepteur de la mélatonine de type MT1/métabolisme , Récepteur de la mélatonine de type MT2/agonistes , Récepteur de la mélatonine de type MT2/métabolisme , Souris de lignée C57BL , Monoamine oxidase/métabolisme , Récepteurs à la mélatonine/agonistes , Récepteurs à la mélatonine/métabolisme , Troubles de stress post-traumatique/traitement médicamenteux , Troubles de stress post-traumatique/psychologie , Troubles de stress post-traumatique/métabolisme
10.
Jpn J Radiol ; 2024 Jun 28.
Article de Anglais | MEDLINE | ID: mdl-38937410

RÉSUMÉ

OBJECTIVES: To investigate the diagnostic performance and complication rates of percutaneous transthoracic CT-guided coaxial core needle biopsy (PTCNB) in persistent consolidations and evaluate its safety in routine clinical practice. METHODS: A total of 685 patients (404 males, 281 females) underwent PTCNB with coaxial core technique for persisted consolidation were reviewed in this study. According to histopathological and microbiological analysis, the results of biopsy specimens were categorized as follows: malignant, specific benign, non-specific benign and non-diagnostic. The final diagnosis was established through surgical resection or clinicoradiological follow-up for at least 12 months following biopsy. Diagnostic yield of PTCNB was defined as the percentage of the true diagnosis from biopsy as malignant and specific benign lesions. RESULTS: With respect to the final diagnosis, 54 (54/685; 7.88%) cases were obtained by surgery and the remaining were by follow-up. The total accuracy, sensitivity, specificity of PTCNB for malignancy diagnosis was 94.45%, 84.87%, 100%, respectively. Diagnostic yield of PTCNB was 66.28%. Compared to lesions smaller than 3 cm, higher diagnostic yield (70.89%), lower complication incidence (38.22%) and shorter procedure time (8.78 min) were observed in lesions ≥ 3 cm group. CONCLUSION: PTCNB in persistent consolidation is a safe and effective procedure, which provide relatively high diagnostic yield and acceptable complication, especially in size over 3 cm lesions. CRITICAL RELEVANCE STATEMENT: CT-guided coaxial needle biopsy for pulmonary consolidation is a safe and effective procedure. The coaxial needle biopsy yielded high diagnostic rates and low complication rates (including pneumothorax and intrapulmonary hemorrhage), especially in larger lesions.

11.
Clin Nephrol ; 2024 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-38916495

RÉSUMÉ

BACKGROUND: Therapeutic approaches that target the gut microbiota may be helpful in the potential prevention and treatment of membranous nephropathy (MN). Several studies demonstrated a correlation between gut microbiota and MN. However, the confounding evidence cannot prove a causal relationship between gut microbiota and MN. MATERIALS AND METHODS: The aim of our study is to assess genome-wide association study data for a causal relationship between gut microbiota and MN using a two-sample Mendelian randomization (MR) approach. Inverse variance weighted (IVW) was used as the primary technique to determine the association of genetic variants from gut microbiota and MN patients. Besides, sensitivity analyses confirmed the accuracy of the results. Finally, we applied false discovery rate (FDR) correction to results with IVW < 0.05 during multiple hypothesis testing. RESULTS: The results from IVW estimates indicated that Bacillales exhibited a significant association with MN, acting as a risk factor (OR = 1.52, 95% CI: 1.14 - 2.02, p = 0.005). In addition, our univariable MR results showed that 7 bacterial taxa (Melainabacteria, Butyricicoccus, Catenibacterium, Ruminiclostridium5, RuminococcaceaeUCG003, RuminococcaceaeUCG013, and Gastranaerophilales) had suggestive associations with MN. The sensitivity analysis did not reveal any significant heterogeneity in the instrumental variables or horizontal pleiotropy. CONCLUSION: Our findings provided causal evidence for the effect of gut microbiota on MN patients and broadened the spectrum of bacterial taxa that might be involved in the pathogenesis of MN. These selected bacterial taxa hold promise as new biomarkers, which may aid in designing targeted therapeutic modalities for MN, improving our comprehension of the gut-kidney axis.

12.
Chemistry ; : e202401561, 2024 Jun 07.
Article de Anglais | MEDLINE | ID: mdl-38847762

RÉSUMÉ

Gelatin polymers made from partially degraded collagen are important biomaterials, but their in-situ analysis suffers from uncontrollable covalent labelling and poor spatio-temporal imaging resolution. Herein, three tetrazolate-tagged tetraphenylethylene fluorophores (TPE-TAs) are introduced for practical fluorogenic labelling of gelatin in aqueous phase and hydrogels. These probes with aggregation-induced emission characteristics offer negligible background and elicit turn-on fluorescence by simply mixing with the gelatin in aqueous phase, giving a detection limit of 0.15 mg/L over a linear dynamic range up to 100 mg/L. This method does not work for collagens and causes minimal interference with gelatin properties. Mechanistic studies reveal a key role for multivalent electrostatic interactions between the abundant basic residues in gelatin (e.g., lysine, hydroxylysine, arginine) and anionic tetrazolate moieties of the lipophilic fluorophore synergistically in spatially rigid macromolecular encapsulation to achieve fluorogenic labelling. The AIE strategy by forming non-covalent fluorophore-gelatin complexes was developed for novel hydrogels that exhibited reversible fluorescence in response to dynamic microstructural changes in the hydrogel scaffold upon salting-in/out treatments, and enabled high spatio-temporal imaging of the fiber network in lyophilized samples. This work may open up avenues for in-situ imaging analysis and evaluation of gelatin-based biomaterials during processes such as in vivo degradation and mineralization.

13.
Sensors (Basel) ; 24(9)2024 May 03.
Article de Anglais | MEDLINE | ID: mdl-38733031

RÉSUMÉ

This study aimed to propose a portable and intelligent rehabilitation evaluation system for digital stroke-patient rehabilitation assessment. Specifically, the study designed and developed a fusion device capable of emitting red, green, and infrared lights simultaneously for photoplethysmography (PPG) acquisition. Leveraging the different penetration depths and tissue reflection characteristics of these light wavelengths, the device can provide richer and more comprehensive physiological information. Furthermore, a Multi-Channel Convolutional Neural Network-Long Short-Term Memory-Attention (MCNN-LSTM-Attention) evaluation model was developed. This model, constructed based on multiple convolutional channels, facilitates the feature extraction and fusion of collected multi-modality data. Additionally, it incorporated an attention mechanism module capable of dynamically adjusting the importance weights of input information, thereby enhancing the accuracy of rehabilitation assessment. To validate the effectiveness of the proposed system, sixteen volunteers were recruited for clinical data collection and validation, comprising eight stroke patients and eight healthy subjects. Experimental results demonstrated the system's promising performance metrics (accuracy: 0.9125, precision: 0.8980, recall: 0.8970, F1 score: 0.8949, and loss function: 0.1261). This rehabilitation evaluation system holds the potential for stroke diagnosis and identification, laying a solid foundation for wearable-based stroke risk assessment and stroke rehabilitation assistance.


Sujet(s)
, Photopléthysmographie , Réadaptation après un accident vasculaire cérébral , Accident vasculaire cérébral , Humains , Réadaptation après un accident vasculaire cérébral/instrumentation , Réadaptation après un accident vasculaire cérébral/méthodes , Photopléthysmographie/méthodes , Photopléthysmographie/instrumentation , Accident vasculaire cérébral/physiopathologie , Mâle , Femelle , Adulte d'âge moyen , Adulte , Pléthysmographie/méthodes , Pléthysmographie/instrumentation , Conception d'appareillage , Dispositifs électroniques portables , Algorithmes
14.
Article de Anglais | MEDLINE | ID: mdl-38696295

RÉSUMÉ

This review aims to provide a systematic analysis of the literature focused on the use of intelligent control systems in robotics for physical rehabilitation, identifying trends in recent research and comparing the effectiveness of intelligence used in control, with the aim of determining important factors in robot-assisted rehabilitation and how intelligent controller design can improve them. Seven electronic research databases were searched for articles published in the years 2015 - 2022 with articles selected based on relevance to the subject area of intelligent control systems in rehabilitation robotics. It was found that the most common use of intelligent algorithms for control is improving traditional control strategies with optimization and learning techniques. Intelligent algorithms are also commonly used in sensor output mapping, model construction, and for various data learning purposes. Experimental results show that intelligent controllers consistently outperform non-intelligent controllers in terms of transparency, tracking accuracy, and adaptability. Active participation of the patients and lowered interaction forces are consistently mentioned as important factors in improving the rehabilitation outcome as well as the patient experience. However, there are limited examples of studies presenting experimental results with impaired participants suffering limited range of motion, so the effectiveness of therapy provided by these systems is often difficult to quantify. A lack of universal evaluation criteria also makes it difficult to compare control systems outside of articles which use their own comparison criteria.


Sujet(s)
Algorithmes , Intelligence artificielle , Robotique , Humains , Réadaptation/méthodes , Réadaptation/instrumentation , Résultat thérapeutique
15.
Sci Adv ; 10(20): eadi7024, 2024 May 17.
Article de Anglais | MEDLINE | ID: mdl-38758791

RÉSUMÉ

At the synapse, presynaptic neurotransmitter release is tightly controlled by release machinery, involving the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins and Munc13. The Ca2+ sensor Doc2 cooperates with Munc13 to regulate neurotransmitter release, but the underlying mechanisms remain unclear. In our study, we have characterized the binding mode between Doc2 and Munc13 and found that Doc2 originally occludes Munc13 to inhibit SNARE complex assembly. Moreover, our investigation unveiled that EphB2, a presynaptic adhesion molecule (SAM) with inherent tyrosine kinase functionality, exhibits the capacity to phosphorylate Doc2. This phosphorylation attenuates Doc2 block on Munc13 to promote SNARE complex assembly, which functionally induces spontaneous release and synaptic augmentation. Consistently, application of a Doc2 peptide that interrupts Doc2-Munc13 interplay impairs excitatory synaptic transmission and leads to dysfunction in spatial learning and memory. These data provide evidence that SAMs modulate neurotransmitter release by controlling SNARE complex assembly.


Sujet(s)
Protéines de liaison au calcium , Protéines de tissu nerveux , Agents neuromédiateurs , Récepteur EphB2 , Protéines SNARE , Transmission synaptique , Protéines SNARE/métabolisme , Animaux , Agents neuromédiateurs/métabolisme , Protéines de tissu nerveux/métabolisme , Phosphorylation , Récepteur EphB2/métabolisme , Récepteur EphB2/génétique , Protéines de liaison au calcium/métabolisme , Liaison aux protéines , Humains , Souris , Rats
16.
Mikrochim Acta ; 191(5): 281, 2024 Apr 23.
Article de Anglais | MEDLINE | ID: mdl-38649632

RÉSUMÉ

Two chiral covalent organic frameworks (CCOFs) core-shell microspheres based on achiral organic precursors by chiral-induced synthesis strategy for HPLC enantioseparation are reported for the first time. Using n-hexane/isopropanol as mobile phase, various kinds of racemates were selected as analytes and separated on the CCOF-TpPa-1@SiO2 and CCOF-TpBD@SiO2-packed columns with a low column backpressure (3 ~ 9 bar). The fabricated two CCOFs@SiO2 chiral columns exhibited good separation performance towards various racemates with high column efficiency (e.g., 19,500 plates m-1 for (4-fluorophenyl)ethanol and 18,900 plates m-1 for 1-(4-chlorophenyl)ethanol) and good reproducibility. Some effects have been investigated such as the analyte mass and column temperature on the HPLC enantioseparation. Moreover, the chiral separation results of the CCOF-TpPa-1@SiO2 chiral column and the commercialized Chiralpak AD-H column show a good complementarity. This study demonstrates that the usage of chiral-induced synthesis strategy for preparing CCOFs core-shell microspheres as a novel stationary phase has a good application potential in HPLC.

17.
Article de Anglais | MEDLINE | ID: mdl-38557618

RÉSUMÉ

Upper limb functional impairments persisting after stroke significantly affect patients' quality of life. Precise adjustment of robotic assistance levels based on patients' motion intentions using sEMG signals is crucial for active rehabilitation. This paper systematically reviews studies on continuous prediction of upper limb single joints and multi-joint combinations motion intention using Model-Based (MB) and Model-Free (MF) approaches over the past decade, based on 186 relevant studies screened from six major electronic databases. The findings indicate ongoing challenges in terms of subject composition, algorithm robustness and generalization, and algorithm feasibility for practical applications. Moreover, it suggests integrating the strengths of both MB and MF approaches to improve existing algorithms. Therefore, future research should further explore personalized MB-MF combination methods incorporating deep learning, attention mechanisms, muscle synergy features, motor unit features, and closed-loop feedback to achieve precise, real-time, and long-duration prediction of multi-joint complex movements, while further refining the transfer learning strategy for rapid algorithm deployment across days and subjects. Overall, this review summarizes the current research status, significant findings, and challenges, aiming to inspire future research on predicting upper limb motion intentions based on sEMG.

18.
Appl Opt ; 63(6): 1546-1552, 2024 Feb 20.
Article de Anglais | MEDLINE | ID: mdl-38437367

RÉSUMÉ

Underwater wireless optical communication (UWOC) has attracted considerable interest owing to its capability of high data rates and low latency. As a crucial component of UWOC, the transmission characteristics of an underwater channel directly impact the system's performance metrics. However, the existing channel models cannot exactly capture the underwater channel states, thus degrading the observability of channel states. This paper proposes a hybrid-field channel model containing both far-field and near-field path components, in which the signal-dependent shot noise (SDSN) is incorporated as well to accurately describe the underwater channel behavior. Then an improved orthogonal matching pursuit (I-OMP) algorithm that estimates the far-field and near-field path components independently with different transform matrices is developed to obtain the underwater channel state. The performance analyses show that I-OMP can improve the estimation accuracy of underwater channels by iteratively minimizing the mean square error (MSE) and utilizing two different transform matrices, demonstrating the advantage of the proposed I-OMP over the existing methods.

19.
J Am Chem Soc ; 146(11): 7506-7514, 2024 Mar 20.
Article de Anglais | MEDLINE | ID: mdl-38457476

RÉSUMÉ

Very recently, a new superconductor with Tc = 80 K has been reported in nickelate (La3Ni2O7) at around 15-40 GPa conditions (Nature, 621, 493, 2023), which is the second type of unconventional superconductor, besides cuprates, with Tc above liquid nitrogen temperature. However, the phase diagram plotted in this report was mostly based on the transport measurement under low-temperature and high-pressure conditions, and the assumed corresponding X-ray diffraction (XRD) results were carried out at room temperature. This encouraged us to carry out in situ high-pressure and low-temperature synchrotron XRD experiments to determine which phase is responsible for the high Tc state. In addition to the phase transition from the orthorhombic Amam structure to the orthorhombic Fmmm structure, a tetragonal phase with the space group of I4/mmm was discovered when the sample was compressed to around 19 GPa at 40 K where the superconductivity takes place in La3Ni2O7. The calculations based on this tetragonal structure reveal that the electronic states that approached the Fermi energy were mainly dominated by the eg orbitals (3dz2 and 3dx2-y2) of Ni atoms, which are located in the oxygen octahedral crystal field. The correlation between Tc and this structural evolution, especially Ni-O octahedra regularity and the in-plane Ni-O-Ni bonding angles, is analyzed. This work sheds new light to identify what is the most likely phase responsible for superconductivity in double-layered nickelate.

20.
J Pharmacol Sci ; 154(4): 225-235, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38485340

RÉSUMÉ

In this study, we investigated the regulatory mechanisms underlying the effects of LPS tolerance on the inflammatory homeostasis of immune cells. LPS priming-induced immune tolerance downregulated cyclooxygenase-2, and lowered the production of prostaglandin-E2 in microglial cells. In addition, LPS tolerance downregulated the expression of suppressor of cytokine signaling 3, and inducible nitric oxide synthase/nitric oxide; suppressed the LPS-mediated induction of tumor necrosis factor-α, interleukin (IL)-6, and IL-1; and reduced reactive oxygen species production in microglial cells. LPS stimulation increased the levels of the adaptive response-related proteins heme oxygenase-1 and superoxide dismutase 2, and the levels of heme oxygenase-1 (HO-1) enhanced after LPS priming. Systemic administration of low-dose LPS (0.5 mg/kg) to mice for 4 consecutive days attenuated high-dose LPS (5 mg/kg)-induced inflammatory response, microglial activation, and proinflammatory cytokine expression. Moreover, repeated exposure to low-dose LPS suppressed the recruitment of peripheral monocytes or macrophages to brain regions and downregulated the expression of proinflammatory cytokines. Notably, LPS-induced social avoidance behaviors in mice were mitigated by immune tolerance. In conclusion, immune tolerance may reduce proinflammatory cytokine expression and reactive oxygen species production. Our findings provide insights into the effects of endotoxin tolerance on innate immune cells and social behaviors.


Sujet(s)
Heme oxygenase-1 , Microglie , Animaux , Souris , Heme oxygenase-1/métabolisme , Microglie/métabolisme , Lipopolysaccharides/pharmacologie , Facteur de transcription NF-kappa B/métabolisme , Espèces réactives de l'oxygène/métabolisme , Apprentissage par évitement , Cytokines/métabolisme , Interleukine-6/métabolisme , Comportement social , Tolérance immunitaire , Nitric oxide synthase type II/métabolisme , Monoxyde d'azote/métabolisme
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