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Ischemic stroke is a leading cause of death and disability worldwide, with an increasing trend and tendency for onset at a younger age. China, in particular, bears a high burden of stroke cases. In recent years, the inflammatory response after stroke has become a research hotspot: understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its treatment. This review summarizes several major cells involved in the inflammatory response following ischemic stroke, including microglia, neutrophils, monocytes, lymphocytes, and astrocytes. Additionally, we have also highlighted the recent progress in various treatments for ischemic stroke, particularly in the field of stem cell therapy. Overall, understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient outcomes. Stem cell therapy may potentially become an important component of ischemic stroke treatment.
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Mitochondrial homeostasis serves as a cornerstone of cellular function, orchestrating a delicate balance between energy production, redox status, and cellular signaling transduction. This equilibrium involves a myriad of interconnected processes, including mitochondrial dynamics, quality control mechanisms, and biogenesis and degradation. Perturbations in mitochondrial homeostasis have been implicated in a wide range of diseases, including neurodegenerative diseases, metabolic syndromes, and aging-related disorders. In the past decades, the discovery of numerous mitochondrial proteins and signaling has led to a more complete understanding of the intricate mechanisms underlying mitochondrial homeostasis. Recent studies have revealed that Family with sequence similarity 210 member A (FAM210A) is a novel nuclear-encoded mitochondrial protein involved in multiple aspects of mitochondrial homeostasis, including mitochondrial quality control, dynamics, cristae remodeling, metabolism, and proteostasis. Here, we review the function and physiological role of FAM210A in cellular and organismal health. This review discusses how FAM210A acts as a regulator on mitochondrial inner membrane to coordinate mitochondrial dynamics and metabolism.
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The strong resource constraints of edge-computing devices and the dynamic evolution of load characteristics put forward higher requirements for forecasting methods of active distribution networks. This paper proposes a lightweight adaptive ensemble learning method for local load forecasting and predictive control of active distribution networks based on edge computing in resource constrained scenarios. First, the adaptive sparse integration method is proposed to reduce the model scale. Then, the auto-encoder is introduced to downscale the model variables to further reduce computation time and storage overhead. An adaptive correction method is proposed to maintain the adaptability. Finally, a multi-timescale predictive control method for the edge side is established, which realizes the collaboration of local load forecasting and control. All cases can be deployed on an actual edge-computing device. Compared to other benchmark methods and the existing researches, the proposed method can minimize the model complexity without reducing the forecasting accuracy.
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The corrosion behaviors of two bridge steels (Q345q and Q500q) under simulated ultraviolet irradiation and a wet-dry alternating (UVWD) environment were studied. Weight loss measurement, stereomicroscope observation, SEM, XRD, and electrochemical impedance spectroscopy (EIS) were performed to investigate the influence of the coupled environment. The results revealed that the corrosion rates of Q345q and Q500q were significantly accelerated by the synergistic effect of UV light exposure and alternating wet-dry conditions. Numerous voids and cracks could be observed throughout the thickened rust layers, enabling the corrosive substances to easily penetrate through the rust layer. Q500q exhibited better corrosion resistance than Q345q due to the addition of Mo, Cr, and Ni as corrosion-resistant elements, which tended to transform the rust layer into α-FeOOH rather than γ-FeOOH during later stages of corrosion.
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The cell death field has profited from the increasing attention of the scientific community and has been shown to lie at the very basis of cancer initiation and progression. Cuproptosis is a recently proposed method of cell death in 2022, and it is different from any previously reported method. The principle is that copper ions lead to aggregation and instability of intracellular proteins. An increasing number of researchers are dedicated to enriching the mechanism of cuproptosis and exploring its relationship with cancer. Studies have found that intracellular copper levels have an impact on the occurrence and development of lymphoma. The complexity of lymphoma and the limitations of treatment necessitate in-depth studies of the disease. We will review the mechanism of cuproptosis and its potential in lymphoma therapy.
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The combination of nanosecond Pulsed Electric Field (nsPEF) with pharmaceuticals is a pioneering therapeutic method capable of enhancing drug uptake efficacy in cells. Utilizing nsPEFs configured at 400 pulses, an electric field strength of 15 kV/cm, a pulse duration of 100 ns, and a repetition rate of 10 pulses per second (PPS), we combined the nsPEF with a low dose of doxorubicin (DOX) at 0.5 µM. Upon verifying that cells could continuously internalize DOX from the surrounding medium within 1 h post nsPEF exposure, we set the DOX exposure period to 10 min and contrasted the outcomes of varying sequences of DOX and nsPEF administration: pulsing followed by DOX, DOX followed by pulsing, and DOX applied 40 min after pulsing. Flow cytometry, CCK-8 assays, and transmission electron microscopy (TEM) were employed to examine intracellular DOX accumulation, cell viability, apoptosis, cell cycle, and ultrastructural transformations. Our findings demonstrate that exposing cells to DOX 40 min subsequent to nsPEF treatment can effectively elevate intracellular DOX levels, decrease cell viability, and inhibit the cell cycle. This research work presents a novel approach to enhance DOX uptake efficiency with moderate conditions of both DOX and nsPEF.
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This study addresses the challenges in plant pest and disease prediction within the context of smart agriculture, highlighting the need for efficient data processing techniques. In response to the limitations of existing models, which are characterized by slow training speeds and a low prediction accuracy, we introduce an innovative prediction method that integrates gene expression programming (GEP) with support vector machines (SVM). Our approach, the gene expression programming-support vector machine (GEP-SVM) model, begins with encoding and fitness function determination, progressing through cycles of selection, crossover, mutation, and the application of a convergence criterion. This method uniquely employs individual gene values as parameters for SVM, optimizing them through a grid search technique to refine genetic parameters. We tested this model using historical data on wheat blossom midges in Shaanxi Province, spanning from 1933 to 2010, and compared its performance against traditional methods, such as GEP, SVM, naive Bayes, K-nearest neighbor, and BP neural networks. Our findings reveal that the GEP-SVM model achieves a leading back-generation accuracy rate of 90.83%, demonstrating superior generalization and fitting capabilities. These results not only enhance the computational efficiency of pest and disease prediction in agriculture but also provide a scientific foundation for future predictive endeavors, contributing significantly to the optimization of agricultural production strategies.
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BACKGROUND: Despite rapid advances in genomic-resolved metagenomics and remarkable explosion of metagenome-assembled genomes (MAGs), the function of uncultivated anaerobic lineages and their interactions in carbon mineralization remain largely uncertain, which has profound implications in biotechnology and biogeochemistry. RESULTS: In this study, we combined long-read sequencing and metatranscriptomics-guided metabolic reconstruction to provide a genome-wide perspective of carbon mineralization flow from polymers to methane in an anaerobic bioreactor. Our results showed that incorporating long reads resulted in a substantial improvement in the quality of metagenomic assemblies, enabling the effective recovery of 132 high-quality genomes meeting stringent criteria of minimum information about a metagenome-assembled genome (MIMAG). In addition, hybrid assembly obtained 51% more prokaryotic genes in comparison to the short-read-only assembly. Metatranscriptomics-guided metabolic reconstruction unveiled the remarkable metabolic flexibility of several novel Bacteroidales-affiliated bacteria and populations from Mesotoga sp. in scavenging amino acids and sugars. In addition to recovering two circular genomes of previously known but fragmented syntrophic bacteria, two newly identified bacteria within Syntrophales were found to be highly engaged in fatty acid oxidation through syntrophic relationships with dominant methanogens Methanoregulaceae bin.74 and Methanothrix sp. bin.206. The activity of bin.206 preferring acetate as substrate exceeded that of bin.74 with increasing loading, reinforcing the substrate determinantal role. CONCLUSION: Overall, our study uncovered some key active anaerobic lineages and their metabolic functions in this complex anaerobic ecosystem, offering a framework for understanding carbon transformations in anaerobic digestion. These findings advance the understanding of metabolic activities and trophic interactions between anaerobic guilds, providing foundational insights into carbon flux within both engineered and natural ecosystems. Video Abstract.
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Carbono , Metagenômica , Metano , Metano/metabolismo , Carbono/metabolismo , Metagenômica/métodos , Reatores Biológicos/microbiologia , Metagenoma , Bactérias/genética , Bactérias/metabolismo , Bactérias/classificação , Filogenia , Anaerobiose , Transcriptoma , Genoma Bacteriano , Microbiota , Perfilação da Expressão GênicaRESUMO
Cardiomyopathy (CM) represents a heterogeneous group of diseases primarily affecting cardiac structure and function, with genetic and epigenetic dysregulation playing a pivotal role in its pathogenesis. Emerging evidence from the burgeoning field of epitranscriptomics has brought to light the significant impact of various RNA modifications, notably N6-methyladenosine (m6A), 5-methylcytosine (m5C), N7-methylguanosine (m7G), N1-methyladenosine (m1A), 2'-O-methylation (Nm), and 6,2'-O-dimethyladenosine (m6Am), on cardiomyocyte function and the broader processes of cardiac and vascular remodelling. These modifications have been shown to influence key pathological mechanisms including mitochondrial dysfunction, oxidative stress, cardiomyocyte apoptosis, inflammation, immune response, and myocardial fibrosis. Importantly, aberrations in the RNA methylation machinery have been observed in human CM cases and animal models, highlighting the critical role of RNA methylating enzymes and their potential as therapeutic targets or biomarkers for CM. This review underscores the necessity for a deeper understanding of RNA methylation processes in the context of CM, to illuminate novel therapeutic avenues and diagnostic tools, thereby addressing a significant gap in the current management strategies for this complex disease.
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OBJECTIVE: Epidemiological studies on spinal cord tumors are rare, and studies on primary intramedullary tumors are even rarer. The incidence and survival of patients with primary intramedullary spinal cord tumors have not been well documented. We aimed to study the incidence and survival of patients with primary spinal cord malignant and borderline malignant tumors based on data from the Surveillance, Epidemiology, and End Results (SEER) database and provide information for revealing the epidemiology and exploring the prognosis of patients with primary intramedullary tumors. METHODS: Patients in the SEER database with microscopically diagnosed malignant and borderline malignant primary spinal cord tumors from 2000 and 2019 were included in this study. We analyzed the distribution of patients according to the demographic and clinical characteristics. Then, we extracted the incidence rate and 5-year relative survival for the whole cohort and different subgroups of the cohort. Finally, multivariate Cox proportional hazards models were used to analyze the independent prognostic factors associated with overall survival. RESULTS: A total of 5,211 patients with malignant and borderline malignant primary spinal cord tumors were included in this cohort study. Ependymoma, astrocytoma (including oligodendrogliomas and glioblastoma), lymphoma and hemangioblastoma were the most common pathological types. The age-adjusted incidence rates of primary spinal cord ependymoma was 0.18 per 100,000. The incidence rate for females was significantly lower than that for males. The incidence rate was highest in Caucasian. The incidence rate of ependymoma was significantly higher than that of other pathological types. The incidence of astrocytoma was highest among people aged 0-19 years, the incidence of ependymoma was highest among people aged 40-59 years, and the incidence of lymphoma was highest among people aged 60 years or older. The 5-year observed survival and relative survival rates for the whole cohort were 82.80% and 86.00%, respectively. Patients diagnosed with ependymoma had significantly better survival than their counterparts. We also found the impact of surgery and chemotherapy on the prognosis of patients with different tumors varies a lot. CONCLUSION: We conducted a population-based analysis of malignant and borderline malignant primary spinal cord tumors with the aim of revealing the epidemiology and survival of patients with primary intramedullary spinal cord tumors. Despite some shortcomings, this study provides valuable information to help us better understand the epidemiological characteristics of primary intramedullary spinal cord tumors.
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The ion association of salts aqueous solutions have long captivated the attention of researchers within the field of physical chemistry. In this paper, we have performed a comprehensive analysis of ion interactions in sodium sulfate (Na2SO4) aqueous solutions using a combination of high-resolution techniques, including excess (ERS) and two-dimensional correlation (2DCRS) Raman spectroscopy in conjunction with molecular dynamics (MD) calculations. The Raman spectrum shows that two inflection points in the Raman shift of the O-H vibration are observed with the increase in Na2SO4 concentration. Simultaneously, a new peak of the SO42- vibration appears at first inflection point, representing the formation of ion association. Further analysis based on ERS and 2CRS reveals that these two inflection points correspond respectively to the formation of ion pairs (CIPs) and small ion clusters. Importantly, MD simulations confirm the above experimental results. Our study provides evidence for ion association and clustering in aqueous in salt ion aqueous solutions.
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Somatic mutations related to clonal hematopoiesis of indeterminate potential (CHIP) are risk factors for stroke. The impact of DNMT3A, the most mutated gene in CHIP, on clinical functional outcomes of acute ischemic stroke (AIS) remains unclear. In a well-characterized cohort of 8524 ischemic stroke patients, we demonstrated that DNMT3A-driven CHIP was significantly associated with neurological disability in these patients. With a stroke mouse model of transient middle cerebral artery occlusion (tMCAO), we demonstrated that DNMT3A protein levels in the brain penumbra increased. The DNMT3A inhibitor RG108 administration amplified neutrophil proliferation in the blood, promoted neutrophil infiltration into the brain penumbra, and exaggerated proinflammatory activation in tMCAO male mice. DNMT3A inhibition also significantly increased infarct volume and worsened neurobehavioral function in tMCAO male mice. In conclusion, DNMT3A somatic mutations are associated with worsened neurological disability in some patients with AIS, potentially through increased neutrophil proliferation and infiltration in the ischemic brain region. These findings suggest a possible mechanism for proinflammatory activation and tissue damage in the affected brain tissue, highlighting the need for further research in this area.
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In recent years, the use of arsenic trioxide (ATO) in the context of ovarian cancer chemotherapy has attracted significant attention. However, ATO's limited biocompatibility and the occurrence of severe toxic side effects hinder its clinical application. A nanoparticle (NP) drug delivery system using ATO as a therapeutic agent is reported in this study. Achieving a synergistic effect by combining starvation therapy, chemodynamic therapy, and chemotherapy for the treatment of ovarian cancer was the ultimate goal of this system. This nanotechnology-based drug delivery system (NDDS) introduced arsenic-manganese complexes into cancer cells, leading to the subsequent release of lethal arsenic ions (As3+) and manganese ions (Mn2+). The acidic microenvironment of the tumor facilitated this process, and MR imaging offered real-time monitoring of the ATO dose distribution. Simultaneously, to produce reactive oxygen species that induced cell death through a Fenton-like reaction, Mn2+ exploited the surplus of hydrogen peroxide (H2O2) within tumor cells. Glucose oxidase-based starvation therapy further supported this mechanism, which restored H2O2 and lowered the cellular acidity. Consequently, this approach achieved self-enhanced chemodynamic therapy. Homologous targeting of the NPs was facilitated through the use of SKOV3 cell membranes that encapsulated the NPs. Hence, the use of a multimodal NDDS that integrated ATO delivery, therapy, and monitoring exhibited superior efficacy and biocompatibility compared with the nonspecific administration of ATO. This approach presents a novel concept for the diagnosis and treatment of ovarian cancer.
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Antineoplásicos , Trióxido de Arsênio , Nanopartículas , Neoplasias Ovarianas , Feminino , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Humanos , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral , Trióxido de Arsênio/administração & dosagem , Trióxido de Arsênio/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacologia , Nanopartículas/química , Manganês/química , Manganês/administração & dosagem , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Materiais Biomiméticos/química , Materiais Biomiméticos/administração & dosagem , Camundongos Nus , Sistemas de Liberação de Medicamentos/métodos , Sistemas de Liberação de Fármacos por Nanopartículas/química , Glucose Oxidase/administração & dosagem , Camundongos Endogâmicos BALB CRESUMO
Spinal epidural angiolipomas are rare, benign, mesenchymal tumors. It remains unclear whether spinal epidural angiolipomas are genuinely rare or merely underreported. Herein, we assessed the demographic and clinical characteristics of patients with spinal epidural angiolipoma. We collected data from patients with spinal epidural angiolipoma from three sources. First, we retrospectively analyzed data from patients diagnosed with spinal epidural angiolipoma in our hospital between January 1, 2014, and December 31, 2023. Second, we performed a literature review of studies retrieved from PubMed. Third, we retrieved detailed data of patients with spinal angiolipoma from the Surveillance, Epidemiology, and End Results (SEER) database. We conducted a descriptive analysis to investigate the demographic and clinical characteristics of patients with spinal epidural angiolipoma. At our institution, three patients were diagnosed with spinal epidural angiolipoma. Additionally, we identified 116 patients from the literature review and 15 patients from the SEER database. We reviewed the treatment history and imaging features of the three patients from our institution. The descriptive analysis of the data collected from the literature review was consistent with previous reports. For example, 63.0% of lesions were located at the thoracic level. 31.9% of these lesions involved two vertebral bodies, while 75.6% involved 2-4 vertebral bodies. The most common symptoms experienced by patients were back pain, paraparesis, and numbness in the legs. Surgery was the primary treatment option for most patients, and complete tumor resection was achieved in the majority of patients. The male:female ratio was 1:1.4, the median age at diagnosis for the patients from the literature was 49 years old, and the median follow-up was 24 months. Notably, most of the reports came from Asia and there were few reports from Africa. The findings from the SEER database indicated a male:female ratio of 2:1. The peak incidence, which is typically reported in the fifth decade of life, was not observed. We presented three cases of spinal epidural angiolipoma and supplemented our findings with a literature review and population-based analysis according to the SEER database for the United States population. We believe that our research will enhance clinicians' comprehension of this uncommon tumor.
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Angiolipoma , Humanos , Angiolipoma/patologia , Angiolipoma/epidemiologia , Angiolipoma/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Neoplasias Epidurais/epidemiologia , Neoplasias Epidurais/patologia , Neoplasias Epidurais/cirurgia , Idoso , Neoplasias da Coluna Vertebral/epidemiologia , Neoplasias da Coluna Vertebral/patologia , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Imageamento por Ressonância Magnética , Programa de SEERRESUMO
BACKGROUND: The interaction between CD47 and signal-regulatory protein-alpha (SIRPα) inhibits phagocytosis, and their clinicopathological characteristics have been evaluated in various diseases. However, the significance of CD47 and SIRPα expression, as well as the combined effect, in Extranodal Natural killer/T-cell Lymphoma (ENKTL) remains uncertain. METHODS: In total, 76 newly diagnosed ENKTL patients (mean age 49.9 years, 73.7% male) were included in this study. CD47 and SIRPα expression were examined by immunohistochemistry. Survival analyses were conducted through Kaplan-Meier curves and the Cox regression model. RESULTS: Seventy-one (93.4%) cases were categorized as the CD47 positive group and 59 (77.6%) cases were categorized as the SIRPα positive group. CD47-negative cases had more advanced-stage illness (P = 0.001), while SIRPα-positive cases showed significantly lower levels of high-density lipoprotein (P < 0.001). In univariable analysis, CD47, SIRPα expression, and their combination were significantly associated with prognosis (P < 0.05). In multivariable analysis, only positive SIRPα expression remained significantly associated with superior overall survival (Hazard ratio [HR] 0.446; 95% confidence interval [CI] 0.207-0.963; P = 0.004). Furthermore, SIRPα expression could re-stratify the survival of patients in ECOG (< 2), advanced CA stage, PINK (HR), CD38-positive, PD1-positive, and CD30-positive groups. CONCLUSIONS: SIRPα status was a potential independent prognostic factor for ENKTL. The prognostic significance of CD47 expression and the interaction between CD47 and SIRPα in ENKTL need further investigation.
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Antígeno CD47 , Linfoma Extranodal de Células T-NK , Receptores Imunológicos , Humanos , Antígeno CD47/metabolismo , Antígeno CD47/análise , Antígeno CD47/biossíntese , Masculino , Pessoa de Meia-Idade , Feminino , Receptores Imunológicos/metabolismo , Receptores Imunológicos/biossíntese , Linfoma Extranodal de Células T-NK/metabolismo , Linfoma Extranodal de Células T-NK/patologia , Linfoma Extranodal de Células T-NK/mortalidade , Adulto , Idoso , Antígenos de Diferenciação/biossíntese , Antígenos de Diferenciação/análise , Imuno-Histoquímica , Prognóstico , Taxa de SobrevidaRESUMO
Sapphire is a promising wideband substrate material for visible photonics. It is a common growth substrate for III-nitride light-emitting diodes and laser structures. Doped sapphires are important gain media foundational to the development of titanium-sapphire and ruby lasers. For lasers operating at visible and near-infrared wavelengths, a photonic platform that minimizes loss while maximizing gain material overlap is crucial. Here, we introduce a novel low-loss waveguiding strategy that establishes high-performance integrated photonics on sapphire substrates. This platform achieves a high intrinsic quality factor of 5.6 million near 780 nm and features direct compatibility with a range of solid-state laser gain media.
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BACKGROUND: Drought is a leading environmental factor affecting plant growth. To explore the drought tolerance mechanism of asparagus, this study analyzed the responses of two asparagus varieties, namely, 'Jilv3' (drought tolerant) and 'Pacific Early' (drought sensitive), to drought stress using metabolomics and transcriptomics. RESULTS: In total, 2,567 and 7,187 differentially expressed genes (DEGs) were identified in 'Pacific Early' and 'Jilv3', respectively, by comparing the transcriptome expression patterns between the normal watering treatment and the drought stress treatment. These DEGs were significantly enriched in the amino acid biosynthesis, carbon metabolism, phenylpropanoid biosynthesis, and plant hormone signal transduction pathways. In 'Jilv3', DEGs were also enriched in the following energy metabolism-related pathways: citrate cycle (TCA cycle), glycolysis/gluconeogenesis, and pyruvate metabolism. This study also identified 112 and 254 differentially accumulated metabolites (DAMs) in 'Pacific Early' and 'Jilv3' under drought stress compared with normal watering, respectively. The amino acid, flavonoid, organic acid, and soluble sugar contents were more significantly enhanced in 'Jilv3' than in 'Pacific Early'. According to the metabolome and transcriptome analysis, in 'Jilv3', the energy supply of the TCA cycle was improved, and flavonoid biosynthesis increased. As a result, its adaptability to drought stress improved. CONCLUSIONS: These findings help to better reveal the molecular mechanism underlying how asparagus responds to drought stress and improve researchers' ability to screen drought-tolerant asparagus varieties as well as breed new varieties.
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Asparagus , Secas , Metabolômica , Transcriptoma , Asparagus/genética , Asparagus/metabolismo , Asparagus/fisiologia , Perfilação da Expressão Gênica , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , MetabolomaRESUMO
Background: Physical exertion during exercise often leads to increased oxidative stress and inflammatory responses, significantly affecting physical performance. Current strategies to mitigate these effects are limited by their effectiveness and potential side effects. Molecular hydrogen (H2) has gained attention for its antioxidant and anti-inflammatory properties. Studies have suggested that H2 supplementation contributes to antioxidant potential and anti-fatigue during exercise, but the variance in the observations and study protocols is presented across those studies. Objective: This systematic review and meta-analysis aimed to comprehensively characterize the effects of H2 supplementation on physical performance (i.e., endurance, muscular strength, and explosive power), providing knowledge that can inform strategies using H2 for enhancing physical performance. Methods: We conducted a literature search of six databases (PubMed, Web of Science, Medline, Sport-Discus, Embase, and PsycINFO) according to the PRISMA guidelines. The data were extracted from the included studies and converted into the standardized mean difference (SMD). After that, we performed random-effects meta-analyses and used the I 2 statistic to evaluate heterogeneity. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to assess the quality of the evidence obtained from this meta-analysis. Results: In total, 27 publications consisting of 597 participants were included. The search finally included aerobic endurance, anaerobic endurance, muscular strength, lower limb explosive power, rating of perceived exertion (RPE), blood lactate (BLA), and average heart rate (HRavg) in the effect size (ES) synthesis. The ES of H2 on aerobic endurance, including VÌO2max (SMD = 0.09, p = 0.394; I 2 = 0%) and aerobic endurance exercise (SMD = 0.04, p = 0.687; I 2 = 0%), were not significant and trivial; the ES of H2 on 30 s maximal anaerobic endurance (SMD = 0.19, p = 0.239; I 2 = 0%) was not significant and trivial; the ES of H2 on muscular strength (SMD = 0.19, p = 0.265; I 2 = 0%) was not significant and trivial; but the ES of H2 on lower limb explosive power (SMD = 0.30, p = 0.018; I 2 = 0%) was significant and small. In addition, H2 reduces RPE (SMD = -0.37, p = 0.009; I 2 = 58.0%) and BLA (SMD = -0.37, p = 0.001; I 2 = 22.0%) during exercise, but not HRavg (SMD = -0.27, p = 0.094; I 2 = 0%). Conclusion: These findings suggest that H2 supplementation is favorable in healthy adults to improve lower limb explosive power, alleviate fatigue, and boost BLA clearance, but may not be effectively improving aerobic and anaerobic endurance and muscular strength. Future studies with more rigorous designs are thus needed to examine and confirm the effects of H2 on these important functionalities in humans. Systematic review registration: http://www.crd.york.ac.uk/PROSPERO.
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Dielectric elastomers, such as thermoplastic polyurethanes (TPUs), are widely used as the dielectric layer, encapsulation layer, and substrate of flexible and stretchable devices. To construct capacitors and actuators that work stably upon deformation, it has become urgent to investigate the evolution of dielectricity under stress and strain. However, the lack of effective methods for estimating the dielectric constant of elastomers under strain poses a big challenge. This study reports a device for the in situ measurement of the dielectric constant of TPU under strain. It is found that upon stretching TPU to a strain of 400%, its dielectric constant decreases from 8.02 ± 0.01 to 2.88 ± 0.25 (at 1 MHz). In addition, combined Fourier-transform infrared spectroscopy, the X-ray scattering technique, and atomic force microscopy were utilized to characterize the evolution of the microstructure under strain. The investigation under tensile strain reveals a decreased density and average size of polarized hard domains, along with a tendency of the molecular chains to align in parallel with the tensile stress. The evolution of the microstructures results in a reduction in the measured dielectric constant in TPU.