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1.
Neural Regen Res ; 20(3): 695-714, 2025 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38886936

RESUMO

Alzheimer's disease, the primary cause of dementia, is characterized by neuropathologies, such as amyloid plaques, synaptic and neuronal degeneration, and neurofibrillary tangles. Although amyloid plaques are the primary characteristic of Alzheimer's disease in the central nervous system and peripheral organs, targeting amyloid-beta clearance in the central nervous system has shown limited clinical efficacy in Alzheimer's disease treatment. Metabolic abnormalities are commonly observed in patients with Alzheimer's disease. The liver is the primary peripheral organ involved in amyloid-beta metabolism, playing a crucial role in the pathophysiology of Alzheimer's disease. Notably, impaired cholesterol metabolism in the liver may exacerbate the development of Alzheimer's disease. In this review, we explore the underlying causes of Alzheimer's disease and elucidate the role of the liver in amyloid-beta clearance and cholesterol metabolism. Furthermore, we propose that restoring normal cholesterol metabolism in the liver could represent a promising therapeutic strategy for addressing Alzheimer's disease.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38980778

RESUMO

This article is committed to studying projective synchronization and complete synchronization (CS) issues for one kind of discrete-time variable-order fractional neural networks (DVFNNs) with time-varying delays. First, two new variable-order fractional (VF) inequalities are built by relying on nabla Laplace transform and some properties of Mittag-Leffler function, which are extensions of constant-order fractional (CF) inequalities. Moreover, the VF Halanay inequality in discrete-time sense is strictly proved. Subsequently, some sufficient projective synchronization and CS criteria are derived by virtue of VF inequalities and hybrid controllers. Finally, we exploit numerical simulation examples to verify the validity of the derived results, and a practical application of the obtained results in image encryption is also discussed.

3.
J Appl Res Intellect Disabil ; 37(5): e13246, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38982871

RESUMO

BACKGROUND: Measurement instruments to understand self-determined motivation towards physical activity among college students with intellectual disabilities are needed to develop programs to support physical and psychological health and well-being. The purpose of the current study was to validate a modified questionnaire measuring basic psychological needs towards physical activity among college students with intellectual disabilities. METHODS: A total of 108 college students with intellectual disabilities completed the modified questionnaire. Validity and reliability of the questionnaire was examined. RESULTS: Confirmatory factor analysis demonstrated a six-factor model had good model fit. Cronbach's alpha values showed acceptable reliability evidence of the instrument as a whole, although some alpha values in subdomains of the instrument were below acceptable values. CONCLUSION: The modified questionnaire was found to have acceptable validity evidence. Further studies are needed with refinement of answer options and the addition of more questions to increase reliability.


Assuntos
Exercício Físico , Deficiência Intelectual , Estudantes , Humanos , Deficiência Intelectual/psicologia , Masculino , Feminino , Adulto Jovem , Estudantes/psicologia , Adulto , Reprodutibilidade dos Testes , Universidades , Psicometria/normas , Psicometria/instrumentação , Adolescente , Inquéritos e Questionários , Motivação
4.
Zool Res ; 45(4): 877-909, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39004865

RESUMO

The tree shrew ( Tupaia belangeri) has long been proposed as a suitable alternative to non-human primates (NHPs) in biomedical and laboratory research due to its close evolutionary relationship with primates. In recent years, significant advances have facilitated tree shrew studies, including the determination of the tree shrew genome, genetic manipulation using spermatogonial stem cells, viral vector-mediated gene delivery, and mapping of the tree shrew brain atlas. However, the limited availability of tree shrews globally remains a substantial challenge in the field. Additionally, determining the key questions best answered using tree shrews constitutes another difficulty. Tree shrew models have historically been used to study hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, myopia, and psychosocial stress-induced depression, with more recent studies focusing on developing animal models for infectious and neurodegenerative diseases. Despite these efforts, the impact of tree shrew models has not yet matched that of rodent or NHP models in biomedical research. This review summarizes the prominent advancements in tree shrew research and reflects on the key biological questions addressed using this model. We emphasize that intensive dedication and robust international collaboration are essential for achieving breakthroughs in tree shrew studies. The use of tree shrews as a unique resource is expected to gain considerable attention with the application of advanced techniques and the development of viable animal models, meeting the increasing demands of life science and biomedical research.


Assuntos
Pesquisa Biomédica , Animais , Pesquisa Biomédica/tendências , Tupaiidae , Modelos Animais de Doenças , Tupaia , Modelos Animais
6.
Cancer Immunol Immunother ; 73(8): 154, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833154

RESUMO

BACKGROUND: Alpha-fetoprotein elevated gastric cancer (AFPGC) got growing interests for its aggressive nature and unfavorable prognosis. Here, a phase 1 dose escalation study was conducted to evaluate safety and efficacy of zimberelimab (GLS-010, anti-PD-1) plus lenvatinib and chemotherapy (XELOX) as the first-line treatment for AFPGC. METHODS: Histologically confirmed HER2-negative, advanced GC patients with elevated serum AFP level (≥ 20 ng/ml) were screened. Using a 3 + 3 dose escalation design, patients were administered varying doses of lenvatinib (12, 16, 20 mg) with GLS-010 and XELOX. The primary endpoints were safety and determination of recommended phase II dose (RP2D). Secondary endpoints included overall response rate (ORR), progression-free survival (PFS) and disease control rate. RESULTS: Nine patients were enrolled with no dose-limiting toxicities observed. Most frequent treatment-related AEs were fatigue (55.6%), hand-foot syndrome (55.6%) and rash (55.6%), and no grade ≥ 4 AEs were reported. All patients exhibited disease control with ORR reaching 33.3%. The median PFS and OS reached 7.67 months (95% CI 4.07-11.27) and 13.17 months (95% CI 2.78-23.56), respectively. Serum AFP level was found correlated with therapeutic responses. Further 16s rRNA sequencing analysis demonstrated altered gut microbiota with elevated abundance of Lachnospiraceae bacterium-GAM79 and Roseburia hominis A2-183. CONCLUSIONS: GLS-010 plus lenvatinib and XELOX demonstrated a manageable safety profile with promising efficacy for AFPGC. With RP2D of lenvatinib determined as 16 mg, further expansion cohort is now ongoing. Translational investigation suggested that serum AFP can be indictive for therapeutic responses and certain microbiota species indicating favorable responses to immunotherapy was elevated after the combinational treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Compostos de Fenilureia , Quinolinas , Neoplasias Gástricas , alfa-Fetoproteínas , Humanos , Quinolinas/uso terapêutico , Quinolinas/administração & dosagem , Masculino , Feminino , Pessoa de Meia-Idade , Compostos de Fenilureia/uso terapêutico , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/mortalidade , Idoso , alfa-Fetoproteínas/metabolismo , alfa-Fetoproteínas/análise , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Adulto , Prognóstico
8.
Respir Res ; 25(1): 261, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943142

RESUMO

AIMS: To detect the expression of autophagy components, p38 MAPK (p38) and phosphorylated forkhead box transcription factor O-1 (pFoxO1) in pulmonary vascular endothelial cells of chronic thromboembolic pulmonary hypertension (CTEPH) rats and to investigate the possible mechanism through which tissue factor (TF) regulates autophagy. METHODS: Pulmonary artery endothelial cells (PAECs) were isolated from CTEPH (CTEPH group) and healthy rats (control group (ctrl group)) which were cocultured with TF at different time points including 12 h, 24 h, 48 h and doses including 0 nM,10 nM, 100 nM, 1µM, 10µM, 100µM and cocultured with TFPI at 48 h including 0 nM, 2.5 nM, 5 nM. The expression of forkhead box transcription factor O-1 (FoxO1), pFoxO1, p38, Beclin-1 and LC3B in PAECs was measured. Coimmunoprecipitation (co-IP) assays were used to detect the interaction between FoxO1 and LC3. RESULTS: The protein expression of p-FoxO1/FoxO1 was significantly lower in the CTEPH groups (cocultured with TF from 0 nM to 100 µM) than in the ctrl group at 12 h, 24 h, and 48 h (P < 0.05) and was significantly lower in the CTEPH groups (cocultured with TFPI from 0 nM to 5 nM) than in the ctrl group at 48 h (P < 0.05). The protein expression of p38 in the CTEPH groups treated with 0 nM, 10 nM, 100 nM or 1 µM TF for 48 h significantly increased than ctrl groups (P < 0.05) and was significantly increased in the CTEPH groups (cocultured with TFPI concentration from 0 nM to 5 nM) than in the ctrl group at 48 h (P < 0.05). The protein expression of Beclin1 at the same concentration (cocultured with TF from 0 nM to 100 µM) was significantly lower in the CTEPH groups than ctrl groups after 24 h and 48 h (P < 0.05) and was significantly decreased in the CTEPH groups (cocultured with TFPI concentration from 2.5 nM to 5 nM) than in the ctrl group at 48 h (P < 0.05). The protein expression of LC3-II/LC3-I at the same concentration (cocultured with TF 0 nM, 1 µM, 10 µM, and 100 µM) was significantly lower in the CTEPH than in the ctrl groups after 12 h (P < 0.05) and was significantly lower in the CTEPH groups (cocultured with TFPI concentration from 0 nM to 5 nM) than in the ctrl group at 48 h (P < 0.05). There were close interactions between FoxO1 and LC3 in the control and CTEPH groups at different doses and time points. CONCLUSION: The autophagic activity of PAECs from CTEPH rats was disrupted. TF, FoxO1 and p38 MAPK play key roles in the autophagic activity of PAECs. TF may regulate autophagic activity through the p38 MAPK-FoxO1 pathway.


Assuntos
Autofagia , Células Endoteliais , Hipertensão Pulmonar , Artéria Pulmonar , Ratos Sprague-Dawley , Tromboplastina , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Autofagia/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Ratos , Masculino , Células Endoteliais/metabolismo , Células Cultivadas , Tromboplastina/metabolismo , Tromboplastina/biossíntese , Hipertensão Pulmonar/metabolismo , Embolia Pulmonar/metabolismo , Embolia Pulmonar/patologia , Doença Crônica , Transdução de Sinais/fisiologia , Proteína Forkhead Box O1
9.
Entropy (Basel) ; 26(6)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38920454

RESUMO

Salient object detection (SOD) aims to accurately identify significant geographical objects in remote sensing images (RSI), providing reliable support and guidance for extensive geographical information analyses and decisions. However, SOD in RSI faces numerous challenges, including shadow interference, inter-class feature confusion, as well as unclear target edge contours. Therefore, we designed an effective Global Semantic-aware Aggregation Network (GSANet) to aggregate salient information in RSI. GSANet computes the information entropy of different regions, prioritizing areas with high information entropy as potential target regions, thereby achieving precise localization and semantic understanding of salient objects in remote sensing imagery. Specifically, we proposed a Semantic Detail Embedding Module (SDEM), which explores the potential connections among multi-level features, adaptively fusing shallow texture details with deep semantic features, efficiently aggregating the information entropy of salient regions, enhancing information content of salient targets. Additionally, we proposed a Semantic Perception Fusion Module (SPFM) to analyze map relationships between contextual information and local details, enhancing the perceptual capability for salient objects while suppressing irrelevant information entropy, thereby addressing the semantic dilution issue of salient objects during the up-sampling process. The experimental results on two publicly available datasets, ORSSD and EORSSD, demonstrated the outstanding performance of our method. The method achieved 93.91% Sα, 98.36% Eξ, and 89.37% Fß on the EORSSD dataset.

10.
Avian Pathol ; : 1-10, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38922304

RESUMO

RESEARCH HIGHLIGHTS: First confirmation of AOAV-16 in domestic and wild birds in China.AOAV-16 are low virulent viruses for chickens.Co-circulation/co-infection of AOAV-16 and H9N2 subtype AIV enhanced pathogenicity.Different intergenic sequences and recombination events exist within AOAV-16.

11.
MedComm (2020) ; 5(7): e617, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38887468

RESUMO

Coffee, a widely consumed beverage, has shown benefits for human health but lacks sufficient basic and clinical evidence to fully understand its impacts and mechanisms. Here, we conducted a cross-sectional observational study of coffee consumption and a 1-month clinical trial in humans. We found that coffee consumption significantly reshaped the immune system and metabolism, including reduced levels of inflammatory factors and a reduced frequency of senescent T cells. The frequency of senescent T cells and the levels of the senescence-associated secretory phenotype were lower in both long-term coffee consumers and new coffee consumers than in coffee nondrinking subjects, suggesting that coffee has anti-immunosenescence effects. Moreover, coffee consumption downregulated the activities of the The Janus kinase/signal transduction and activator of transcription (JAK/STAT) and mitogen-activated protein kinases (MAPK) signaling pathways and reduced systemic proinflammatory cytokine levels. Mechanistically, coffee-associated metabolites, such as 1-methylxanthine, 3-methylxanthine, paraxanthine, and ceramide, reduced the frequency of senescent CD4+CD57+ T cells in vitro. Finally, in vivo, coffee intake alleviated inflammation and immunosenescence in imiquimod-induced psoriasis-like mice. Our results provide novel evidence of the anti-inflammatory and anti-immunosenescence effects of coffee, suggesting that coffee consumption could be considered a healthy habit.

12.
Endocr Relat Cancer ; 31(9)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38904412

RESUMO

Scientific evidence has linked diabetes to a higher incidence and increased aggressiveness of breast cancer; however, mechanistic studies of the numerous regulators involved in this process are insufficiently thorough. Advanced glycation end products (AGEs) play an important role in the chronic complications of diabetes, but the mechanisms of AGEs in breast cancer are largely unexplored. In this study, we first demonstrate that high AGE levels in breast cancer tissues are associated with the diabetic state and poor patient outcomes. Furthermore, AGEs interact with the receptor for AGEs (RAGE) to promote breast cancer cell migration and invasion. Mechanistically, based on RNA sequencing (RNA-seq) analysis, we reveal that growth arrest and DNA damage gene 45α (GADD45α) is a vital protein upregulated by AGEs through a P53-dependent pathway. Next, GADD45α recruits thymine DNA glycosylase for base excision repair to form the demethylation complex at the promoter region of MMP-9 and enhance MMP-9 transactivation through DNA demethylation. Overall, our results indicate a critical regulatory role of AGEs in patients with breast cancer and diabetes and reveal a novel mechanism of epigenetic modification in promoting breast cancer metastasis.


Assuntos
Neoplasias da Mama , Proteínas de Ciclo Celular , Produtos Finais de Glicação Avançada , Metaloproteinase 9 da Matriz , Regiões Promotoras Genéticas , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Feminino , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Produtos Finais de Glicação Avançada/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Reparo do DNA , Metástase Neoplásica , Linhagem Celular Tumoral , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Animais , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Pessoa de Meia-Idade , Proteínas GADD45
13.
Life Sci ; 350: 122744, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810793

RESUMO

AIMS: The prevalence of gestational diabetes mellitus (GDM) has spurred investigations into various interconnected factors, among which gut dysbiosis is notably prominent. Although gut dysbiosis is strongly associated with GDM, the specific role of the gut microbiome in the pathogenesis of GDM remains unknown. This study aims to explore the pathogenesis of GDM from gut microbiota. MATERIALS AND METHODS: In our study, we constructed two GDM mice models: one induced by a high-fat diet (HFD) and the other through fecal microbiota transplantation (FMT) from GDM patients. In vitro, we used a co-culture system of RAW264.7 and 3T3-L1 adipocytes. KEY FINDINGS: We induced a GDM-like state in pregnant mice by FMT from GDM patients, which was consistent with the HFD model. A potential mechanism identified involves the diminished abundance of SCFA-producing microbiota, which reduces SCFAs, particularly propionic acid and butyric acid. In vitro, butyric and propionic acids were observed to alleviate LPS-induced TLR4-NF-κB activation, thereby reducing inflammation levels and inhibiting adipose insulin resistance via the PI3K/AKT signaling pathway. This reduction appears to trigger the polarization of adipose tissue macrophages toward M1 and promote insulin resistance in adipose tissue. SIGNIFICANCE: Our study fills this knowledge gap by finding that alterations in gut microbiota have an independent impact on hyperglycemia and insulin resistance in the GDM state. In vivo and in vitro, gut dysbiosis is linked to adipose tissue inflammation and insulin resistance via the bacterial product SCFAs in the GDM state, providing new insights into the pathogenesis of GDM.


Assuntos
Tecido Adiposo , Diabetes Gestacional , Disbiose , Ácidos Graxos Voláteis , Microbioma Gastrointestinal , Macrófagos , Animais , Diabetes Gestacional/metabolismo , Diabetes Gestacional/microbiologia , Feminino , Disbiose/metabolismo , Camundongos , Gravidez , Macrófagos/metabolismo , Ácidos Graxos Voláteis/metabolismo , Tecido Adiposo/metabolismo , Humanos , Células RAW 264.7 , Resistência à Insulina , Transplante de Microbiota Fecal , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Células 3T3-L1 , Modelos Animais de Doenças
14.
Anal Chem ; 96(23): 9460-9467, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38820243

RESUMO

Pathological cardiac hypertrophy is a complex process that often leads to heart failure. Label-free proteomics has emerged as an important platform to reveal protein variations and to elucidate the mechanisms of cardiac hypertrophy. Endomyocardial biopsy is a minimally invasive technique for sampling cardiac tissue, but it yields only limited amounts of an ethically permissible specimen. After regular pathological examination, the remaining trace samples pose significant challenges for effective protein extraction and mass spectrometry analysis. Herein, we developed trace cardiac tissue proteomics based on the anchor-nanoparticles (TCPA) method. We identified an average of 6666 protein groups using ∼50 µg of myocardial interventricular septum samples by TCPA. We then applied TCPA to acquire proteomics from patients' cardiac samples both diagnosed as hypertrophic hearts and myocarditis controls and identified significant alterations in pathways such as regulation of actin cytoskeleton, oxidative phosphorylation, and cGMP-PKG signaling pathway. Moreover, we found multiple lipid metabolic pathways to be dysregulated in transthyretin cardiac amyloidosis compared to other types of cardiac hypertrophy. TCPA offers a new technique for studying pathological cardiac hypertrophy and can serve as a platform toolbox for proteomic research in other cardiac diseases.


Assuntos
Miocárdio , Nanopartículas , Proteômica , Proteômica/métodos , Humanos , Miocárdio/metabolismo , Miocárdio/patologia , Miocárdio/química , Nanopartículas/química , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomegalia/diagnóstico , Amiloidose/metabolismo , Amiloidose/patologia , Neuropatias Amiloides Familiares
15.
Biomed Pharmacother ; 175: 116775, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38776680

RESUMO

Gestational diabetes mellitus (GDM) is a pregnancy-specific disease characterized by impaired glucose tolerance during pregnancy. Although diagnosis and clinical management have improved significantly, there are still areas where therapeutic approaches need further improvement. Recent evidence suggests that CCL2, a chemokine involved in immunoregulatory and inflammatory processes, is closely related to GDM. However, the potential value for clinical therapeutic applications and the mechanism of CCL2 in adipose tissue macrophages (ATMs) of GDM remain to be elucidated. Here, we found that CCL2 was enriched in macrophages of the visceral adipose tissue from GDM women and HFD-induced GDM mice. The combination of in vitro and in vivo experiments showed that Ccl2 silencing inhibited the inflammatory response of macrophage by blocking calcium transport between ER and mitochondria and reducing excessive ROS generation. Additionally, the ATS-9R/siCcl2 oligopeptide complex targeting adipose tissue was created. Under the delivery of ATS-9R peptide, Ccl2 siRNA is expressed in ATMs, which reduces inflammation in adipose tissue and, as a result, mitigates insulin resistance. All of these findings point to the possibility that the ATS-9R/siCcl2 complex, which targets adipose tissue, is able to reduce insulin resistance in GDM and the inflammatory response in macrophages. The ATS-9R/siCcl2 oligopeptide complex targeting adipose tissue seems to be a viable treatment for GDM pregnancies.


Assuntos
Tecido Adiposo , Quimiocina CCL2 , Diabetes Gestacional , Resistência à Insulina , Macrófagos , Camundongos Endogâmicos C57BL , Oligopeptídeos , Animais , Diabetes Gestacional/metabolismo , Diabetes Gestacional/tratamento farmacológico , Feminino , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Gravidez , Quimiocina CCL2/metabolismo , Camundongos , Humanos , Oligopeptídeos/farmacologia , Tecido Adiposo/metabolismo , Adulto , Dieta Hiperlipídica , Gordura Intra-Abdominal/metabolismo
16.
Food Chem ; 454: 139802, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38797098

RESUMO

Direct surface analysis in ambient conditions provides information on the position and chemical composition of an object at the time of investigation. An angled sampling probe is developed in this work for direct analysis in real time (DART) ionization high-resolution mass spectrometry. The DART ion source and the interface were modified for improved surface resolution, increased ion transfer efficiency, as well as enabling two-dimensional surface scanning. The angled probe DART-MS system was used for investigating a variety of food samples including fruit peels, ginseng root, plant leaves and sections of radish. Abundant signals and distinct chemical profiles are obtained in seconds, and spatial distribution of different molecules across the sample surfaces can be observed. In addition, the developed system can quickly identify the chemical changes when the surfaces were treated. The method is capable of directly evaluating food sample surfaces with different shapes, hardness, and conditions, without any sample pretreatments.


Assuntos
Frutas , Espectrometria de Massas , Espectrometria de Massas/métodos , Frutas/química , Produtos Biológicos/química , Produtos Biológicos/análise , Análise de Alimentos/métodos , Raphanus/química , Panax/química , Folhas de Planta/química , Raízes de Plantas/química
17.
Rev Sci Instrum ; 95(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38739424

RESUMO

Multidimensional microdriving stage is one of the key components to realize precision driving and high-precision positioning. To meet nanometer displacement and positioning in the fields of micro-/nano-machining and precision testing, a new six-degree-of-freedom microdriving stage (6-DOF-MDS) of multilayer spatially distributed piezoelectric ceramic actuators (PZTs) is proposed and designed. The interior of the 6-DOF-MDS is a hollow design. The flexure hinge is used as the transmission mechanism, and the series-parallel hybrid driving of the corresponding PZTs achieves the microtranslation in the X, Y, and Z directions and the microrotation around the three axes of the microdriving stage, forming a microdisplacement mechanism with high rigidity and simple structure, which can realize the microfeed of 6-DOF. The force-displacement theory and lug boss structure optimization of the 6-DOF-MDS are analyzed, while the strength checking and natural frequency of the 6-DOF-MDS are also simulated by the finite element method. In addition, the real-time motion control system of the 6-DOF-MDS is designed based on Advanced RISC Machines. Through a series of verification experiments, the stroke and resolution results of the 6-DOF-MDS are obtained, where the displacements in the X, Y, and Z directions are 20.72, 20.02, and 37.60 µm, respectively. The resolution is better than 0.68 nm. The rotation angles around X, Y, and Z are 38.96″, 33.80″, and 27.87″, respectively, with an angular resolution of 0.063″. Relevant coupling experiments were also performed in this paper; in the full stroke linear running of X-axis, the maximum coupling displacements of the Y- and Z-axes are 1.04 and 0.17 µm, respectively, with the corresponding coupling rates of ∼5.0% and 0.8%. The maximum coupling angles for the X-, Y-, and Z-axes are 0.33″, 0.14″, and 2.30″, respectively. Considering the coupling of the 6-DOF-MDS, decoupling measures and specific mathematical models have also been proposed. The proposed multidimensional microdriving stage achieves subnanometer resolution and can be used for the precise positioning and attitude control of precision instruments at the nano-/subnanometer level.

18.
Int J Psychophysiol ; 200: 112356, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38701899

RESUMO

Using the N-back task, we investigated how memory load influences the neural activity of the Chinese character cognitive subprocess (recognition, updating, and maintenance) in Mainland Chinese speakers. Twenty-seven participants completed the Chinese character N-back paradigm while having their event-related potentials recorded. The study employed time and frequency domain analyses of EEG data. Results showed that accuracy decreased and response times increased with larger N values. For ERPs, N2pc and P300 amplitudes decreased and SW amplitude increased with larger N values. For time frequency analyses, the desynchronization of alpha oscillations decreased after stimulus onset, but the synchronization of alpha oscillations increased during the maintenance phase. The results suggest that greater memory load is related to a decrease in cognitive resources during updating and an increase in cognitive resources during information maintenance. The results of a behavioral-ERP data structural equation model analysis showed that the ERP indicators in the maintenance phase predicted behavioral performance.


Assuntos
Eletroencefalografia , Potenciais Evocados , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Potenciais Evocados/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Memória de Curto Prazo/fisiologia , Desempenho Psicomotor/fisiologia , Reconhecimento Psicológico/fisiologia , Tempo de Reação/fisiologia , Potenciais Evocados P300/fisiologia
19.
Adv Sci (Weinh) ; 11(25): e2402193, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38569521

RESUMO

Hydrogel-based zinc-air batteries (ZABs) are promising flexible rechargeable batteries. However, the practical application of hydrogel-based ZABs is limited by their short service life, narrow operating temperature range, and repair difficulty. Herein, a self-healing ionogel is synthesized by the photopolymerization of acrylamide and poly(ethylene glycol) monomethyl ether acrylate in 1-ethyl-3-methylimidazolium dicyanamide with zinc acetate dihydrate and first used as an electrolyte to fabricate self-healing ZABs. The obtained self-healing ionogel has a wide operating temperature range, good environmental and electrochemical stability, high ionic conductivity, satisfactory mechanical strength, repeatable and efficient self-healing properties enabled by the reversibility of hydrogen bonding, and the ability to inhibit the production of dendrites and by-products. Notably, the self-healing ionogel has the highest ionic conductivity and toughness compared to other reported self-healing ionogels. The prepared self-healing ionogel is used to assemble self-healing flexible ZABs with a wide operating temperature range. These ZABs have ultra-long cycling lives and excellent stability under harsh conditions. After being damaged, the ZABs can repeatedly self-heal to recover their battery performance, providing a long-lasting and reliable power supply for wearable devices. This work opens new opportunities for the development of electrolytes for ZABs.

20.
Comput Struct Biotechnol J ; 23: 1298-1310, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38560280

RESUMO

In gestational diabetes mellitus (GDM), adipose tissue undergoes metabolic disturbances and chronic low-grade inflammation. Alternative polyadenylation (APA) is a post-transcriptional modification mechanism that generates mRNA with variable lengths of 3' untranslated regions (3'UTR), and it is associated with inflammation and metabolism. However, the role of APA in GDM adipose tissue has not been well characterized. In this study, we conducted transcriptomic and proteomic sequencing on subcutaneous and omental adipose tissues from both control and GDM patients. Using Dapars, a novel APA quantitative algorithm, we delineated the APA landscape of adipose tissue, revealing significant 3'UTR elongation of mRNAs in the GDM group. Omental adipose tissue exhibited a significant correlation between elongated 3'UTRs and reduced translation levels of genes related to metabolism and inflammation. Validation experiments in THP-1 derived macrophages (TDMs) demonstrated the impact of APA on translation levels by overexpressing long and short 3'UTR isoforms of a representative gene LRRC25. Additionally, LRRC25 was validated to suppress proinflammatory polarization in TDMs. Further exploration revealed two underexpressed APA trans-acting factors, CSTF3 and PPP1CB, in GDM omental adipose tissue. In conclusion, this study provides preliminary insights into the APA landscape of GDM adipose tissue. Reduced APA regulation in GDM omental adipose tissue may contribute to metabolic disorders and inflammation by downregulating gene translation levels. These findings advance our understanding of the molecular mechanisms underlying GDM-associated adipose tissue changes.

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