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The collective migration of keratinocytes during wound healing requires both the generation and transmission of mechanical forces for individual cellular locomotion and the coordination of movement across cells. Leader cells along the wound edge transmit mechanical and biochemical cues to ensuing follower cells, ensuring their coordinated direction of migration across multiple cells. Despite the observed importance of mechanical cues in leader cell formation and in controlling coordinated directionality of cell migration, the underlying biophysical mechanisms remain elusive. The mechanically-activated ion channel PIEZO1 was recently identified to play an inhibitory role during the reepithelialization of wounds. Here, through an integrative experimental and mathematical modeling approach, we elucidate PIEZO1's contributions to collective migration. Time-lapse microscopy reveals that PIEZO1 activity inhibits leader cell formation at the wound edge. To probe the relationship between PIEZO1 activity, leader cell formation and inhibition of reepithelialization, we developed an integrative 2D continuum model of wound closure that links observations at the single cell and collective cell migration scales. Through numerical simulations and subsequent experimental validation, we found that coordinated directionality plays a key role during wound closure and is inhibited by upregulated PIEZO1 activity. We propose that PIEZO1-mediated retraction suppresses leader cell formation which inhibits coordinated directionality between cells during collective migration.
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Canais Iônicos , Queratinócitos , Movimento Celular/fisiologiaRESUMO
Aqueous proton batteries (APBs) have emerged as one of the most promising batteries for large-scale energy storage technology. However, they usually show an undesirable electrochemical performance. Herein, we demonstrate a novel aqueous catalytic hydrogen gas powered organic proton (HOP) battery, which is driven by hydrogen evolution/oxidation redox reactions via commercial nanocatalysts on the anode and coordination/decoordination reactions of CâO with H+ on the cathode. The HOP battery shows an excellent rate capacity of 190.1 mAh g-1 at 1 A g-1 and 71.4 mAh g-1 at 100 A g-1. It also delivers a capacity of 96.6 mAh g-1 after 100000 cycles and operates at temperatures down to -70 °C. Moreover, the HOP battery is fabricated in a large-scale pouch cell with an extended capacity, exhibiting its potential for practical energy storage applications. This work provides new insights into the building of sustainable APBs, which will broaden the horizons of high-performance aqueous batteries.
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BACKGROUND: The effects of exogenous brassinolide (BR) treatment (3.0 µmol L-1 ) on phenolic biosynthesis in mung bean sprouts were investigated. This investigation included the analysis of sugar content, substrates within the phenylpropane pathway, energy substances, enzymatic activity within the phenylpropane pathway, sugar metabolism and energy metabolism. RESULTS: Results showed that BR treatment significantly increased the levels of total phenolics, p-hydroxybenzoic acid, p-coumaric acid, gallic acid, fumalic acid and caffeic acid. This enhancement was accomplished through the elevation of l-phenylalanine levels and the activation of enzymes associated with the phenylpropane pathway in mung bean sprouts, including phenylalanine ammonia-lyase, cinnamate 4-hydroxylase and 4-coumarate CoA ligase. Furthermore, BR treatment induced alterations in sugar metabolism in mung bean sprouts as evidenced by the increased levels of glucose, fructose, sucrose and phosphoenolpyruvate. Moreover, increased activity was observed for enzymes linked to sucrose metabolism and glycolysis in the BR-treated group. Concurrently, BR treatment bolstered the levels of adenosine triphosphate and energy charge in mung bean sprouts, which was attributed to the activation of H+ -adenosine triphosphatase, Ca2+ -adenosine triphosphatase and succinic dehydrogenase. CONCLUSION: These results suggest that BR treatment can accelerate the accumulation of phenolic compounds in mung bean sprouts. This effect is achieved not only through the activation of the phenylpropane pathway, but also through the modulation of sugar and energy metabolism. The modulation provides ample energy and a substrate for the biosynthesis of phenolics. © 2023 Society of Chemical Industry.
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Vigna , Vigna/química , Açúcares/metabolismo , Metabolismo Energético , Sacarose/metabolismo , Adenosina Trifosfatases/metabolismoRESUMO
The electrochemical conversion of nitrate pollutants into value-added ammonia is a feasible way to achieve artificial nitrogen cycle. However, the development of electrocatalytic nitrate-to-ammonia reduction reaction (NO3 - RR) has been hampered by high overpotential and low Faradaic efficiency. Here we develop an iron single-atom catalyst coordinated with nitrogen and phosphorus on hollow carbon polyhedron (denoted as Fe-N/P-C) as a NO3 - RR electrocatalyst. Owing to the tuning effect of phosphorus atoms on breaking local charge symmetry of the single-Fe-atom catalyst, it facilitates the adsorption of nitrate ions and enrichment of some key reaction intermediates during the NO3 - RR process. The Fe-N/P-C catalyst exhibits 90.3 % ammonia Faradaic efficiency with a yield rate of 17980â µg h-1 mgcat -1 , greatly outperforming the reported Fe-based catalysts. Furthermore, operando SR-FTIR spectroscopy measurements reveal the reaction pathway based on key intermediates observed under different applied potentials and reaction durations. Density functional theory calculations demonstrate that the optimized free energy of NO3 - RR intermediates is ascribed to the asymmetric atomic interface configuration, which achieves the optimal electron density distribution. This work demonstrates the critical role of atomic-level precision modulation by heteroatom doping for the NO3 - RR, providing an effective strategy for improving the catalytic performance of single atom catalysts in different electrochemical reactions.
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BACKGROUND: This study was aimed to explore the clinical application of dual-energy computed tomography (DECT) monoenergetic plus (mono+) imaging to evaluate anatomical variations in the inferior mesenteric artery (IMA). METHODS: The clinical and imaging data of 212 patients who had undergone total abdominal DECT were retrospectively analyzed. The post-processing mono+ technique was used to obtain 40-keV single-level images in the arterial phase. Three-dimensional reconstruction was performed to evaluate the relationship between the IMA root position and the spinal level, IMA length, and IMA branch type, as well as the position of the left colic artery (LCA) and inferior mesenteric vein (IMV) at the IMA root level. RESULTS: The IMA root was located at the L3 level in 78.3% of cases and at the L2/L3 level in 3.3%. The highest vertebral level of IMA origin was L2 (4.2%), and the lowest was L4 (7.1%). The distance from the IMA root to the level of the sacral promontory was 99.58 ± 13.07 mm, which increased with the elevation of the IMA root at the spinal level. Of the patients, 53.8% demonstrated Type I IMA, 23.1% Type II, 20.7% Type III, and 2.4% Type IV. The length of the IMA varied from 13.6 to 66.0 mm. 77.3% of the IMAs belonged to Type A, the adjacent type, and 22.7% to Type B, the distant type. CONCLUSION: DECT mono+ can preoperatively evaluate the anatomical characteristics of the IMA and the positional relationship between the LCA and IMV at the IMA root level, which would help clinicians plan individualized surgery for patients.
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Artéria Mesentérica Inferior , Veias Mesentéricas , Abdome , Artérias , Humanos , Artéria Mesentérica Inferior/diagnóstico por imagem , Artéria Mesentérica Inferior/cirurgia , Veias Mesentéricas/diagnóstico por imagem , Estudos RetrospectivosRESUMO
OBJECTIVES: An investigation of the effects of different types of the inferior mesenteric artery (IMA) on laparoscopic left colic artery (LCA) radical resection of rectal cancer was conducted. METHODS: Clinical data were collected from 92 patients who underwent laparoscopic radical resection of rectal cancer with preservation of the LCA at Nantong University's Second Affiliated Hospital. All patients underwent full-abdominal dual-energy CT enhancement examination before surgery and 3D post-processing reconstruction of the IMA. Two radiologists with >3 years of experience in abdominal radiology jointly conducted the examination. A total of three types of IMA were identified among the patients: IMA type I (the LCA arising independently from the IMA), type II (LCA and sigmoid colon artery [SA] branching from a common trunk from IMA), and type III (LCA, SA, and superior rectal artery [SRA] branching from the IMA at the same point). The baseline data, pathological results, and intra-operative and post-operative indicators of the groups were analyzed. RESULTS: The proportions of type I, type II, and type III IMA were 58.70% (54/92), 18.48% (17/92), and 22.82% (21/92), respectively. IMA typing was consistent with the preoperative CT evaluation results. The intra-operative blood loss of type III IMA patients [median (interquartile spacing), M (P25, P75): 52.00 (39.50, 68.50) ml] was higher than that of type I and II IMA patients [35.00 (24.00, 42.00) and 32.00 (25.50, 39.50) ml, respectively] (P<0.05). The incidence of anastomotic fistula in type III IMA patients (4 cases, 19.05%) was higher than that in non-type III IMA patients (1 case, 1.41%) (X2=6.679, P=0.010). The incidence of postoperative complications among the three types of IMA was not significantly different (P>0.05). CONCLUSIONS: Among rectal cancer patients undergoing laparoscopic LCA preservation, type III IMA patients had more intraoperative bleeding and a higher incidence of postoperative anastomotic fistula. However, this did not increase the risk of overall postoperative complications.
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Laparoscopia , Neoplasias Retais , Artérias/patologia , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Artéria Mesentérica Inferior/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Neoplasias Retais/patologia , Neoplasias Retais/cirurgiaRESUMO
Disulfiram (DSF) chelated with copper has been confirmed to have a strong anti-tumor ability. In this study, we determined that DSF-Cu induced mitochondria-dependent apoptosis in osteosarcoma (OS), reflecting in DSF-Cu induces mitochondrial membrane potential decline, the production of reactive oxygen species (ROS), and inhibiting cells migration and invasion along with decreasing the concentration of intracellular glutathione (GSH) and facilitating the opening of mitochondrial permeability transition pore (PT) in osteosarcoma cells. These anti-tumor activities can be reversed by Cyclosporine A (CsA, PT inhibitors) and N-acetyl-L-cysteine (NAC, antioxidants). Our results suggested that DSF-Cu exerts its anti-tumor effects in OS via regulation of the ROS/Mitochondria pathway. Our findings provide the basis for DSF-Cu to treat osteosarcoma, even might develop as a potential therapy for other tumors.
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Neoplasias Ósseas/tratamento farmacológico , Dissulfiram/farmacologia , Osteossarcoma/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Quelantes/química , Cobre/química , Dissulfiram/química , Dissulfiram/uso terapêutico , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Osteossarcoma/patologia , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: This retrospective study aimed to investigate the usefulness of the optimized kiloelectron volt (keV) for virtual monoenergetic imaging (VMI) combined with iodine map in dual-energy computed tomography enterography (DECTE) in the diagnosis of Crohn's disease (CD). METHODS: Seventy-two patients (mean age: 41.89 ± 17.28 years) with negative computed tomography enterography (CTE) were enrolled for investigating the optimized VMI keV in DECTE by comparing subjective and objective parameters of VMIs that were reconstructed from 40 to 90 keV. Moreover, 68 patients (38.27 ± 15.10 years; 35 normal and 33 CD) were included for evaluating the diagnostic efficacy of DECTE iodine map at the optimized VMI energy level and routine CTE for CD and active CD. Statistical analysis for all data was conducted. RESULTS: Objective and subjective imaging evaluations showed the best results at 60 keV for VMIs. The CT values of the normal group, active subgroup, and CD group during the small intestinal phase at routine 120 kVp or 60 keV VMI had significant differences. The diagnostic efficacy of an iodine map was the best when NIC = 4% or fat value = 45.8% for CD, whereas NIC < 0.35 or the fat value < 0.38 for active CD. The combined routine CTE and optimized VMI improved the diagnostic efficacy (P < 0.001). CONCLUSIONS: VMI at 60 keV provided the best imaging quality on DECTE. NIC and fat value provided important basis for active CD evaluation. Routine CTE combined with VMI at 60 keV improved the diagnostic efficiency for CD.
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Doença de Crohn/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos RetrospectivosRESUMO
The Sci-Tech Commissioner System (SCS) is a result of exploratory efforts by the Chinese government to use science and technology to strengthen the agricultural sector. Social network analysis (SNA) and machine learning (ML) techniques make it feasible to assess the service performance in China's SCS by using indicators such as group types and structure features. In this study, SNA and a clustering algorithm were employed to categorize service group types of sci-tech commissioners. By comparing the accuracy of different classification algorithms in predicting the clustering results, LightGBM algorithm was finally select to determine the clustering features of sci-tech commissioners and establish an interpretable ML model. Then, the SHAP was used to algorithm to analyze influences affecting service performance. Results show that the service forms of sci-tech commissioners are group-oriented, and that group types include small groups of young commissioners with close cooperation, larger groups of young and middle-aged commissioners, small groups of middle-aged and old commissioners with close cooperation, and isolated points of highly-influential commissioners. Furthermore, while group size is not the determinant of a commissioner's average performance, group structure and coordination ability were found to be more critical. Moreover, while differences in distinct types of service performance are caused by various factors, but good group structures and extensive social contacts are essential for high service performance.
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BACKGROUND: To compare the integrity, clarity, conciseness, etc., of the structured report (SR) versus free-text report (FTR) for computed tomography enterography of Crohn's disease (CD). METHODS: FTRs and SRs were generated for 30 patients with CD. The integrity, clarity, conciseness etc., of SRs versus FTRs, were compared. In this study, an evidence-based medicine practice model was utilized on 92 CD patients based on SR in order to evaluate its clinical value. Then, the life quality of the patients in two groups was evaluated before and after three months of intervention using an Inflammatory Bowel Disease Questionnaire (IBDQ). RESULTS: SRs received higher ratings for satisfaction with integrity (median rating 4.27 vs. 3.75, P=0.008), clarity (median rating 4.20 vs. 3.43, P=0.003), conciseness (median rating 4.23 vs. 3.20, P=0.003), the possibility of contacting a radiologist to interpret (median rating 4.17 vs. 3.20, P<0.001), and overall clinical impact (median rating 4.23 vs. 3.27, P<0.001) than FTRs. Besides, research group had higher score of IBDQ intestinal symptom dimension (median score 61.13 vs. 58.02, P=0.003), IBDQ systemic symptom dimension (median score 24.48 vs. 20.67, P<0.001), IBDQ emotional capacity dimension (median score 65.65 vs. 61.74, P<0.001), IBDQ social ability dimension (median score 26.80 vs. 22.37, P<0.001), and total IBDQ score (median score 178.07 vs. 162.80, P<0.001) than control group. CONCLUSION: The SR of CTE in CD patients was conducive to improving the quality and readability of the report, and CD patients' life quality could significantly improve after the intervention of an evidence-based medicine model based on SR.
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Micro-sensors, such as pressure and flow sensors, are usually adopted to attain actual fluid information around swimming biomimetic robotic fish for hydrodynamic analysis and control. However, most of the reported micro-sensors are mounted discretely on body surfaces of robotic fish and it is impossible to analyzed the hydrodynamics between the caudal fin and the fluid. In this work, a biomimetic caudal fin integrated with a resistive pressure sensor is designed and fabricated by laser machined conductive carbon fibre composites. To analyze the pressure exerted on the caudal fin during underwater oscillation, the pressure on the caudal fin is measured under different oscillating frequencies and angles. Then a model developed from Bernoulli equation indicates that the maximum pressure difference is linear to the quadratic power of the oscillating frequency and the maximum oscillating angle. The fluid disturbance generated by caudal fin oscillating increases with an increase of oscillating frequency, resulting in the decrease of the efficiency of converting the kinetic energy of the caudal fin oscillation into the pressure difference on both sides of the caudal fin. However, perhaps due to the longer stability time of the disturbed fluid, this conversion efficiency increases with the increase of the maximum oscillating angle. Additionally, the pressure variation of the caudal fin oscillating with continuous different oscillating angles is also demonstrated to be detected effectively. It is suggested that the caudal fin integrated with the pressure sensor could be used for sensing thein situflow field in real time and analyzing the hydrodynamics of biomimetic robotic fish.
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Nadadeiras de Animais , Biomimética , Desenho de Equipamento , Peixes , Robótica , Natação , Animais , Robótica/instrumentação , Nadadeiras de Animais/fisiologia , Biomimética/instrumentação , Biomimética/métodos , Peixes/fisiologia , Natação/fisiologia , Hidrodinâmica , Análise de Falha de Equipamento , Transdutores de Pressão , Pressão , Materiais Biomiméticos , TransdutoresRESUMO
Traditional noble metal oxide, such as RuO2, is considered a benchmark catalyst for acidic oxygen evolution reaction (OER). However, its practical application is limited due to sluggish activity and severe electrochemical corrosion. In this study, Ru-Fe nanoparticles loading on carbon felt (RuFe@CF) is synthesized via an ultrafast Joule heating method as an active and durable OER catalyst in acidic conditions. Remarkably low overpotentials of 188 and 269 mV are achieved at 10 and 100 mA cm-2, respectively, with a robust stability up to 620 h at 10 mA cm-2. When used as an anode in a proton exchange membrane water electrolyzer, the catalyst shows more than 250 h of stability at a water-splitting current of 200 mA cm-2. Experimental characterizations reveal the presence of a Ru-based oxide nanosheath on the surface of the catalyst during OER tests, suggesting a surface reconstruction process that enhances the intrinsic activity and inhibits continuous metal dissolution. Moreover, density functional theory calculations demonstrate that the introduction of Fe into the RuFe@CF catalyst reduces the energy barrier and boosts its activities. This work offers an effective and universal strategy for the development of highly efficient and stable catalysts for acidic water splitting.
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The repair of diabetic wounds remains challenging, primarily due to the high-glucose-derived immune inhibition which often leads to the excessive inflammatory response, impaired angiogenesis, and heightened susceptibility to infection. However, the means to reduce the immunosuppression and regulate the conversion of M2 phenotype macrophages under a high-glucose microenvironment using advanced biomaterials for diabetic wounds are not yet fully understood. Herein, we report two-dimensional carbide (MXene)-M2 macrophage exosome (Exo) nanohybrids (FM-Exo) for promoting diabetic wound repair by overcoming the high-glucose-derived immune inhibition. FM-Exo showed the sustained release of M2 macrophage-derived exosomes (M2-Exo) up to 7 days and exhibited broad-spectrum antibacterial activity. In the high-glucose microenvironment, relative to the single Exo, FM-Exo could significantly induce the optimized M2a/M2c polarization ratio of macrophages by activating the PI3K/Akt signaling pathway, promoting the proliferation, migration of fibroblasts, and angiogenic ability of endothelial cells. In the diabetic full-thickness wound model, FM-Exo effectively regulated the polarization status of macrophages and promoted their transition to the M2 phenotype, thereby inhibiting inflammation, promoting angiogenesis through VEGF secretion, and improving proper collagen deposition. As a result, the healing process was accelerated, leading to a better healing outcome with reduced scarring. Therefore, this study introduced a promising approach to address diabetic wounds by developing bioactive nanomaterials to regulate immune inhibition in a high-glucose environment.
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Diabetes Mellitus , Exossomos , Nanocompostos , Nitritos , Elementos de Transição , Humanos , Cicatrização , Células Endoteliais , Exossomos/metabolismo , Fosfatidilinositol 3-Quinases , Diabetes Mellitus/metabolismo , Glucose/metabolismo , Nanocompostos/uso terapêuticoRESUMO
The development of efficient, stable, and low-cost bifunctional catalysts for the hydrogen evolution/oxidation reaction (HER/HOR) is critical to promote the application of hydrogen gas batteries in large scale energy storage systems. Here we demonstrate a non-noble metal high-entropy alloy grown on Cu foam (NNM-HEA@CF) as a self-supported catalytic electrode for nickel-hydrogen gas (Ni-H2) batteries. Experimental and theoretical calculation results reveal that the NNM-HEA catalyst greatly facilitates the HER/HOR catalytic process through the optimized electronic structures of the active sites. The assembled Ni-H2 battery with NNM-HEA@CF as the anode shows excellent rate capability and exceptional cycling performance of over 1800 h without capacity decay at an areal capacity of 15 mAh cm-2. Furthermore, a scaled-up Ni-H2 battery fabricated with an extended capacity of 0.45 Ah exhibits a high cell-level energy density of â¼109.3 Wh kg-1. Moreover, its estimated cost reaches as low as â¼107.8 $ kWh-1 based on all key components of electrodes, separator and electrolyte, which is reduced by more than 6 times compared to that of the commercial Pt/C-based Ni-H2 battery. This work provides an approach to develop high-efficiency non-noble metal-based bifunctional catalysts for hydrogen batteries in large-scale energy storage applications.
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With the increasing use of social media, online self-organized relief has become a crucial aspect of crisis management during public health emergencies, leading to the emergence of online self-organizations. This study employed the BERT model to classify the replies of Weibo users and used K-means clustering to summarize the patterns of self-organized groups and communities. We then combined the findings from pattern discovery and documents from online relief networks to analyze the core components and mechanisms of online self-organizations. Our findings indicate the following: (1) The composition of online self-organized groups follows Pareto's law. (2) Online self-organized communities are mainly composed of sparse and small groups with loose connections, and bot accounts can automatically identify those in need and provide them with helpful information and resources. (3) The core components of the mechanism of online self-organized rescue groups include the initial gathering of groups, the formation of key groups, the generation of collective action, and the establishment of organizational norms. This study suggests that social media can establish an authentication mechanism for online self-organizations, and that authorities should encourage online interactive live streams about public health issues. However, it is important to note that self-organizations are not a panacea for all issues during public health emergencies.
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Saúde Pública , Mídias Sociais , Humanos , Saúde Pública/métodos , Emergências , PersonalidadeRESUMO
Enzymes are critical for cellular functions, and malfunction of enzymes is closely related to many human diseases. Inhibition studies can help in deciphering the physiological roles of enzymes and guide conventional drug development programs. In particular, chemogenetic approaches enabling rapid and selective inhibition of enzymes in mammalian cells have unique advantages. Here, we describe the procedure for rapid and selective inhibition of a kinase in mammalian cells by bioorthogonal ligand tethering (iBOLT). Briefly, a non-canonical amino acid bearing a bioorthogonal group is genetically incorporated into the target kinase by genetic code expansion. The sensitized kinase can react with a conjugate containing a complementary biorthogonal group linked with a known inhibitory ligand. As a result, tethering of the conjugate to the target kinase allows selective inhibition of protein function. Here, we demonstrate this method by using cAMP-dependent protein kinase catalytic subunit alpha (PKA-Cα) as the model enzyme. The method should be applicable to other kinases, enabling their rapid and selective inhibition.
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Aminoácidos , Proteínas , Animais , Humanos , Ligantes , Proteínas/química , Fosforilação , Aminoácidos/química , Mamíferos/metabolismoRESUMO
Fibrous scaffolds have shown their advantages in tissue engineering, such as peripheral nerve regeneration, while most of the existing fiber-shaped scaffolds are with simple structures, and the in vitro performance for nerve regeneration lacks systematic analysis. Here, novel nerve-on-a-chip derived biomimicking microfibers for peripheral nerve regeneration are presented. The microfibers with controllable core-shell structures and functionalities are generated through capillary microfluidic devices. By integrating these microfibers into a multitrack-architectured chip, and coculturing them with nerve cells as well as gradient bioactive elements, the nerve-on-a-chip with the capabilities of systematically assessing the performances of nerve fiber formation in the hollow microfibers at in vitro level is constructed. Based on a rat sciatic nerve injury model, the rapid promotion ability is demonstrated of optimized microfibers in nerve regeneration and function recovery in vivo, which implies the credibility of the nerve-on-a-chip on biomimicking microfibers evaluation for peripheral nerve regeneration. Thus, it is convinced that the organ-on-a-chip will undoubtedly open up a new chapter in evaluating biological scaffolds for in vivo tissue engineering.
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Regeneração Nervosa , Engenharia Tecidual , Ratos , Animais , Dispositivos Lab-On-A-ChipRESUMO
Peripheral nerve injury is a serious medical problem with limited surgical and clinical treatment options. It is of great significance to integrate multiple guidance cues in one platform of nerve guidance conduits (NGCs) to promote axonal elongation and functional recovery. Here, a multi-functional NGC is constructed to promote nerve regeneration by combining ordered topological structure, density gradient of biomacromolecular nanoparticles, and controlled delivery of biological effectors to provide the topographical, haptotactic, and biological cues, respectively. On the surface of aligned polycaprolactone nanofibers, a density gradient of bioactive nanoparticles capable of delivering recombinant human acidic fibroblast growth factor is deposited. On the graded scaffold, the proliferation of Schwann cells is promoted, and the directional extension of neurites from both PC12 cells and dorsal root ganglions is improved in the direction of increasing particle density. After being implanted in vivo for 6 and 12 weeks to repair a 10-mm rat sciatic nerve defect, the NGC promotes axonal elongation and remyelination, achieving the regeneration of the nerve not only in anatomical structure but also in functional recovery. Taken together, the NGC provides a favorable microenvironment for peripheral nerve regeneration and holds great promise for realizing nerve repair with an efficacy close to autograft.
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Nanopartículas , Nervo Isquiático , Ratos , Animais , Humanos , Axônios , Alicerces Teciduais/química , Regeneração NervosaRESUMO
Objective: To evaluate the effects of exercise therapy on patients with poststroke cognitive impairment and compare the differences in the effect of this method when compared with conventional measures, providing evidence for a more standardized and effective clinical application of exercise therapy. Methods: A search was conducted using 7 electronic databases, including PubMed, CINAHL, Web of Science, CENTRAL, CNKI, Wanfang, SinoMed, and clinical trials registry platforms for randomized controlled trials concerning exercise therapy on patients with poststroke cognitive impairment. Two researchers independently screened the literature, evaluated the quality, and extracted information. Meta-analysis was carried out using Review Manager 5.4 software. Results: There were 11 studies with 1,382 patients. Meta-analysis showed that exercise therapy could improve cognitive function [SMD = 0.67, 95% CI (0.31, 1.04), P = 0.0003], motor function [SMD = 1.81, 95% CI (0.41, 3.20), P = 0.01], and the activities of daily living [MD = 8.11, 95% CI (3.07, 13.16), P = 0.002] in patients with poststroke cognitive impairment. Conclusion: Exercise therapy can not only improve cognitive function in patients with poststroke cognitive impairment but also improve motor function and the activities of daily living. Medical staff should prioritize the management of patients with poststroke cognitive impairment and carry out exercise therapy actively to improve the cognitive function of patients with stroke. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42023397553.
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Oxidative stress plays a crucial role in the pathogenesis of hepatic encephalopathy (HE), but the mechanism remains unclear. GABAergic neurons in substantia nigra pars reticulata (SNr) contribute to the motor deficit of HE. The present study aims to investigate the effects of oxidative stress on HE in male mice. The results validate the existence of oxidative stress in both liver and SNr across two murine models of HE induced by thioacetamide (TAA) and bile duct ligation (BDL). Systemic mitochondria-targeted antioxidative drug mitoquinone (Mito-Q) rescues mitochondrial dysfunction and oxidative injury in SNr, so as to restore the locomotor impairment in TAA and BDL mice. Furthermore, the GAD2-expressing SNr population (SNrGAD2) is activated by HE. Both overexpression of mitochondrial uncoupling protein 2 (UCP2) targeted to SNrGAD2 and SNrGAD2-targeted chemogenetic inhibition targeted to SNrGAD2 rescue mitochondrial dysfunction in TAA-induced HE. These results define the key role of oxidative stress in the pathogenesis of HE.