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1.
Artigo em Inglês | MEDLINE | ID: mdl-39297850

RESUMO

BACKGROUND: Myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) using stress cardiovascular magnetic resonance (CMR) have been shown to identify epicardial coronary artery disease. However, comparative analysis between quantitative perfusion and conventional qualitative assessment (QA) remains limited. OBJECTIVES: The aim of this multicenter study was to test the hypothesis that quantitative stress MBF (sMBF) and MPR analysis can identify obstructive coronary artery disease (obCAD) with comparable performance as QA of stress CMR performed by experienced physicians in interpretation. METHODS: The analysis included 127 individuals (mean age 62 ± 16 years, 84 men [67%]) who underwent stress CMR. obCAD was defined as the presence of stenosis ≥50% in the left main coronary artery or ≥70% in a major vessel. Each patient, coronary territory, and myocardial segment was categorized as having either obCAD or no obCAD (noCAD). Global, per coronary territory, and segmental MBF and MPR values were calculated. QA was performed by 4 CMR experts. RESULTS: At the patient level, global sMBF and MPR were significantly lower in subjects with obCAD than in those with noCAD, with median values of sMBF of 1.5 mL/g/min (Q1-Q3: 1.2-1.8 mL/g/min) vs 2.4 mL/g/min (Q1-Q3: 2.1-2.7 mL/g/min) (P < 0.001) and median values of MPR of 1.3 (Q1-Q3: 1.0-1.6) vs 2.1 (Q1-Q3: 1.6-2.7) (P < 0.001). At the coronary artery level, sMBF and MPR were also significantly lower in vessels with obCAD compared with those with noCAD. Global sMBF and MPR had areas under the curve (AUCs) of 0.90 (95% CI: 0.84-0.96) and 0.86 (95% CI: 0.80-0.93). The AUCs for QA by 4 physicians ranged between 0.69 and 0.88. The AUC for global sMBF and MPR was significantly better than the average AUC for QA. CONCLUSIONS: This study demonstrates that sMBF and MPR using dual-sequence stress CMR can identify obCAD more accurately than qualitative analysis by experienced CMR readers.

2.
Biosens Bioelectron ; 267: 116775, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39276438

RESUMO

Hydrogel and aerogel materials have garnered significant attention in constructing effective surface-enhanced Raman spectroscopy (SERS) substrates due to their excellent adsorption capabilities, high specific surface area, and abundant chemical groups. However, in liquids with complex compositions, non-specific adsorption of macromolecules can lead to surface scaling and pore clogging of the substrate material, limiting the selective enrichment and SERS detection of target molecules. To address this, an innovative aerogel-chimeric hydrogel material (CH@S-CNF/SA/Ag NPs) was developed. The aerogel component, with its high specific surface area and electronegative properties, functions as a SERS "chip" for adsorption and detection of target molecules. Simultaneously, the mesoporous structure of the hydrogel "shell" effectively filters macromolecules from the solution. These CH@S-CNF/SA/Ag NPs were utilized as SERS substrate materials for detecting urine from healthy individuals and patients with chronic kidney disease stage 5 (CKD5). When combined with machine learning algorithms, the detection accuracy reached 99.50%. This work represents a significant advancement in the specific adsorption and SERS detection of small molecules in complex biological samples such as urine and blood.

3.
Aquat Toxicol ; 275: 107077, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39236549

RESUMO

Hexafluoropropylene oxide trimer acid (HFPO-TA), an alternative to perfluorooctanoic acid, has been shown to have estrogenic effects. However, its potential to disrupt fish sex differentiation during gonadal development remains unknown. Therefore, this study exposed zebrafish to HFPO-TA from approximately 2 hours post fertilization (hpf) to 60 days post fertilization (dpf) to investigate its effects on sex differentiation. Results indicated that HFPO-TA disrupted steroid hormone homeostasis, delayed gonadal development in both sexes, and resulted in a female-skewed sex ratio in zebrafish. HFPO-TA exposure up-regulated gene expressions of cyp19a1a, esr1, vtg1 and foxl2, while down-regulated those of amh, sox9a and dmrt1. These suggested that HFPO-TA dysregulated the expressions of key genes related to sex differentiation of zebrafish, promoted the production and activation of estrogen, and further induced the feminization. Interestingly, we observed promoter hypomethylation of cyp19a1a and promoter hypermethylation of amh in male zebrafish, which were negatively associated with their gene expressions. These suggested that HFPO-TA dysregulated these key genes through DNA methylation in their promoters. Therefore, the HFPO-TA disrupted the sex differentiation of zebrafish through an epigenetic mechanism involving DNA methylation, ultimately skewing the sex ratio towards females. Overall, this study demonstrated adverse effects of HFPO-TA on fish sex differentiation and provided novel insights into the underlying epigenetic mechanism.


Assuntos
Metilação de DNA , Epigênese Genética , Diferenciação Sexual , Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/genética , Diferenciação Sexual/efeitos dos fármacos , Feminino , Masculino , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Razão de Masculinidade , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fluorocarbonos/toxicidade
4.
Foods ; 13(18)2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39335939

RESUMO

This study aimed to analyze the structure of polysaccharides from eight different Dendrobium species and their protective effects on gastric mucosa. Ultraviolet (UV) analysis showed that the contents of eight polysaccharides ranged from 51.89 ± 6.91% to 80.57 ± 11.63%; the degree of acetylation ranged from 0.17 ± 0.03 to 0.48 ± 0.03. High-performance liquid chromatography (HPLC) results showed that these polysaccharides were mainly composed of mannose (Man) and glucose (Glc) with a small amount of galactose (Gal) and arabinose (Ara), and the monosaccharide ratios of different Dendrobium species were different. High-performance size exclusion chromatography-multi angle light scattering-refractive index detector (HPSEC-MALS-RID) showed that the molecular weight (Mw) of all Dendrobium polysaccharides was >1 × 105 Da; D. huoshanense had the lowest molecular weight. Subsequently, an ethanol injured GES-1 cell model was constructed to evaluate the gastric mucosal protective potential of polysaccharides from eight different Dendrobium species. The results showed that the protective effect of the low concentration 50 µg/mL DHP treatment group was similar to that of the control group (p > 0.05), and the cell viability could reach 97.32% of that of the control group. Based on the polysaccharide composition, different kinds of Dendrobium have different degrees of migration and repair effects on GES-1 damaged cells, and the effect of DHP is slightly better than that of other varieties (83.13 ± 1.05%). Additionally, Dendrobium polysaccharides alleviated ethanol-induced oxidative stress and inflammatory response in gastric mucosal cells by enhancing the activity of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase) and reducing the levels of malondialdehyde and reactive oxygen species. Overall, DHP can most effectively protect gastric mucosa. These findings enhance our understanding of the relationship between the structure and biological activity of Dendrobium polysaccharides, providing a foundation for the quality control of Dendrobium. Furthermore, these findings offer theoretical support for the development of Dendrobium polysaccharides as nutraceuticals to treat digestive system diseases.

5.
Polymers (Basel) ; 16(18)2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39339052

RESUMO

A series of partially bio-based and biodegradable poly(propylene terephthalate-co-adipate) (PPTA) random copolymers with different components were prepared by the melt polycondensation of petro-based adipic acid and terephthalic acid with bio-based 1,3-propanediol. The microstructure, crystallization behavior, thermal properties, and enzymatic degradation properties were further investigated. The thermal decomposition kinetics was deeply analyzed using Friedman's method, with the thermal degradation activation energy ranging from 297.8 to 302.1 kJ/mol. The crystallinity and wettability of the copolymers decreased with the increase in the content of the third unit, but they were lower than those of the homopolymer. The thermal degradation activation energy E, carbon residue, and reaction level n all showed a decreasing trend. Meanwhile, the initial thermal decomposition temperature (Td) was higher than 350 °C, which can meet the requirements for processing and use. The PPTA copolymer material still showed excellent thermal stability. Adding PA units could regulate the crystallinity, wettability, and degradation rate of PPTA copolymers. The composition of PPTA copolymers in different degradation cycles was characterized by 1H NMR analysis. Further, the copolymers' surface morphology during the process of enzymatic degradation also was observed by scanning electron microscopy (SEM). The copolymers' enzymatic degradation accorded with the surface degradation mechanism. The copolymers showed significant degradation behavior within 30 days, and the rate increased with increasing PA content when the PA content exceeded 45.36%.

6.
Chin J Nat Med ; 22(9): 797-807, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39326974

RESUMO

The Chinese herb Ephedra (also known as Mahuang) has been extensively utilized for the prevention and treatment of coronavirus-induced diseases, including coronavirus disease 2019 (COVID-19). However, the specific anti-SARS-CoV-2 compounds and mechanisms have not been fully elucidated. The main protease (Mpro) of SARS-CoV-2 is a highly conserved enzyme responsible for proteolytic processing during the viral life cycle, making it a critical target for the development of antiviral therapies. This study aimed to identify naturally occurring covalent inhibitors of SARS-CoV-2 Mpro from Ephedra and to investigate their covalent binding sites. The results demonstrated that the non-alkaloid fraction of Ephedra (ENA) exhibited a potent inhibitory effect against the SARS-CoV-2 Mpro effect, whereas the alkaloid fraction did not. Subsequently, the chemical constituents in ENA were identified, and the major constituents' anti-SARS-CoV-2 Mpro effects were evaluated. Among the tested constituents, herbacetin (HE) and gallic acid (GA) were found to inhibit SARS-CoV-2 Mpro in a time- and dose-dependent manner. Their combination displayed a significant synergistic effect on this key enzyme. Additionally, various techniques, including inhibition kinetic assays, chemoproteomic methods, and molecular dynamics simulations, were employed to further elucidate the synergistic anti-Mpro mechanisms of the combination of HE and GA. Overall, this study deciphers the naturally occurring covalent inhibitors of SARS-CoV-2 Mpro from Ephedra and characterizes their synergistic anti-Mpro synergistic effect, providing robust evidence to support the anti-coronavirus efficacy of Ephedra.


Assuntos
Antivirais , Proteases 3C de Coronavírus , Ephedra , SARS-CoV-2 , Antivirais/farmacologia , Antivirais/química , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Ephedra/química , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/química , Proteases 3C de Coronavírus/metabolismo , Humanos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Ácido Gálico/farmacologia , Ácido Gálico/química , Tratamento Farmacológico da COVID-19 , Simulação de Acoplamento Molecular , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Flavonoides
7.
J Med Internet Res ; 26: e55576, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39348685

RESUMO

BACKGROUND: Osteoarthritis (OA) is a chronic musculoskeletal disease that causes pain, functional disability, and an economic burden. Nonpharmacological treatments are at the core of OA management. However, limited access to these services due to uneven regional local availability has been highlighted. Internet-based telehealth (IBTH) programs, providing digital access to abundant health care resources, offer advantages, such as convenience and cost-effectiveness. These characteristics make them promising strategies for the management of patients with OA. OBJECTIVE: This study aimed to evaluate the effectiveness of IBTH programs in the management of patients with hip or knee OA. METHODS: We systematically searched 6 electronic databases to identify trials comparing IBTH programs with conventional interventions for hip and knee OA. Studies were selected based on inclusion and exclusion criteria, focusing on outcomes related to function, pain, and self-efficacy. Standardized mean differences (SMDs) with 95% CIs were calculated to compare outcome measures. Heterogeneity was assessed using I² and χ² tests. The methodological quality of the selected studies and the quality of evidence were also evaluated. RESULTS: A total of 21 studies with low-to-high risk of bias were included in this meta-analysis. The pooled results showed that IBTH has a superior effect on increasing function (SMD 0.30, 95% CI 0.23-0.37, P<.001), relieving pain (SMD -0.27, 95% CI -0.34 to -0.19, P<.001), and improving self-efficacy for pain (SMD 0.21, 95% CI 0.08-0.34, P<.001) compared to the conventional intervention group. Subgroup analysis revealed that IBTH with exercise can significantly alleviate pain and improve function and self-efficacy, but IBTH with cognitive-behavioral therapy only had the effect of reducing pain. CONCLUSIONS: The meta-analysis provides moderate-quality evidence that IBTH programs have a beneficial effect on improving function, relieving pain, and improving self-efficacy compared to conventional interventions in patients with hip or knee OA. Limited evidence suggests that the inclusion of exercise regimens in IBTH programs is recommended. TRIAL REGISTRATION: PROSPERO CRD42024541111; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=541111.


Assuntos
Internet , Osteoartrite do Quadril , Osteoartrite do Joelho , Telemedicina , Humanos , Osteoartrite do Joelho/terapia , Osteoartrite do Quadril/terapia
8.
J Phys Chem Lett ; 15(34): 8689-8696, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39159421

RESUMO

Multiferroic materials, known for their multiple tunable orders, present an exceptional opportunity to manipulate nonlinear optical responses that are sensitive to symmetry. In this study, we propose leveraging electric and magnetic fields to selectively control and switch specific types of photogalvanic effects in two-dimensional multiferroic breathing kagome materials. Taking monolayer Nb3I8 as an example, we demonstrate that the shift current, characterized by the real-space shift of electrons and holes, is predominantly unaffected by magnetic order. In contrast, injection current, featured by quantum metric dipole in momentum space, is closely related to valley polarization, which can be controlled by a magnetic field. Furthermore, both photocurrents can be reversed by an out-of-plane electric field via lattice breathing. Our findings reveal the potential of multiferroic breathing kagome structures for multifunctional optoelectronic applications and sensors.

9.
J Cardiovasc Magn Reson ; 26(2): 101085, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39154806

RESUMO

BACKGROUND: Quantitative stress cardiac magnetic resonance (CMR) can be performed using the dual-sequence (DS) technique or dual-bolus (DB) method. It is unknown if DS and DB produce similar results for myocardial blood flow (MBF) and myocardial perfusion reserve (MPR). The study objective is to investigate if there are any differences between DB- and DS-derived MBF and MPR. METHODS: Retrospective observational study with 168 patients who underwent stress CMR. DB and DS methods were simultaneously performed on each patient on the same day. Global and segmental stress MBF and rest MBF values were collected. RESULTS: Using Bland-Altman analysis, segmental and global stress MBF values were higher in DB than DS (0.22 ± 0.60 mL/g/min, p < 0.001 and 0.20 ± 0.48 mL/g/min, p = 0.005, respectively) with strong correlation (r = 0.81, p < 0.001 for segmental and r = 0.82, p < 0.001 for global). In rest MBF, segmental and global DB values were higher than by DS (0.15 ± 0.51 mL/g/min, p < 0.001 and 0.14 ± 0.36 mL/g/min, p = 0.011, respectively) with strong correlation (r = 0.81, p < 0.001 and r = 0.77, p < 0.001). Mean difference between MPR by DB and DS was -0.02 ± 0.68 mL/g/min (p = 0.758) for segmental values and -0.01 ± 0.49 mL/g/min (p = 0.773) for global values. MPR values correlated strongly as well in both segmental and global, both (r = 0.74, p < 0.001) and (r = 0.75, p < 0.001), respectively. CONCLUSION: There is a very good correlation between DB- and DS-derived MBF and MPR values. However, there are significant differences between DB- and DS-derived global stress and rest MBF. While MPR values did not show statistically significant differences between DB and DS methods.

10.
Parkinsonism Relat Disord ; 127: 107080, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39096550

RESUMO

BACKGROUND: Huntington's disease (HD) is a neurodegenerative disorder for which effective therapies are currently lacking. Studies suggest that increasing physical activity (PA) and reducing leisure sedentary behavior (LSB) mitigate the progression of HD, but their causal relationship with the age at onset (AAO) of HD remains uncertain. To investigate this, we conducted the Two-sample Mendelian Randomization (MR). METHODS: Exposure were retrieved from the UK BioBank's (UKB) Genome-Wide Association Study (GWAS). PA included accelerometer-based average PA, vigorous PA, self-reported moderate-to-vigorous PA (MVPA), and light do-it-yourself activity. LSB included television (TV) time, computer time, and driving time. Outcome came from the GWAS of the GEM-HD Consortium. We applied several MR methods such as inverse variance weighted (IVW), MR-Egger regression, weighted median (WM) for sensitivity analysis. RESULTS: Increases in light PA (ß = 8.53 years, 95 % CI = 10.64 to 44.09, P = 0.001) and accelerometer-based vigorous PA (ß = 5.18, 95 % CI = 0.92 to 9.43, P = 0.017) delayed AAO of HD, while longer TV time was associated with earlier AAO of HD (ß = -2.88 years, 95 % CI = -4.99 to -0.77, P = 0.007). However, other PA and LSB phenotypes did not significantly affect AAO of HD. CONCLUSION: The study revealed a unidirectional causality between PA, LSB and the AAO of HD. Increasing PA and reducing TV time delay HD onset. Therefore, we recommend increasing physical activity and reducing sedentary behavior to delay the occurrence of motor symptoms for premanifest HD individuals.

11.
Neural Netw ; 178: 106546, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39053196

RESUMO

Current state-of-the-art medical image segmentation techniques predominantly employ the encoder-decoder architecture. Despite its widespread use, this U-shaped framework exhibits limitations in effectively capturing multi-scale features through simple skip connections. In this study, we made a thorough analysis to investigate the potential weaknesses of connections across various segmentation tasks, and suggest two key aspects of potential semantic gaps crucial to be considered: the semantic gap among multi-scale features in different encoding stages and the semantic gap between the encoder and the decoder. To bridge these semantic gaps, we introduce a novel segmentation framework, which incorporates a Dual Attention Transformer module for capturing channel-wise and spatial-wise relationships, and a Decoder-guided Recalibration Attention module for fusing DAT tokens and decoder features. These modules establish a principle of learnable connection that resolves the semantic gaps, leading to a high-performance segmentation model for medical images. Furthermore, it provides a new paradigm for effectively incorporating the attention mechanism into the traditional convolution-based architecture. Comprehensive experimental results demonstrate that our model achieves consistent, significant gains and outperforms state-of-the-art methods with relatively fewer parameters. This study contributes to the advancement of medical image segmentation by offering a more effective and efficient framework for addressing the limitations of current encoder-decoder architectures. Code: https://github.com/McGregorWwww/UDTransNet.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Semântica , Humanos , Processamento de Imagem Assistida por Computador/métodos , Aprendizado Profundo , Algoritmos
12.
Small Methods ; : e2400258, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38962863

RESUMO

Nanoengineering polar oxide films have attracted great attention in energy storage due to their high energy density. However, most of them are deposited on thick and rigid substrates, which is not conducive to the integration of capacitors and applications in flexible electronics. Here, an alternative strategy using van der Waals epitaxial oxide dielectrics on ultra-thin flexible mica substrates is developed and increased the disorder within the system through high laser flux. The introduction of defects can efficiently weaken or destroy the long-range ferroelectric ordering, ultimately leading to the emergence of a large numbers of weak-coupling regions. Such polarization configuration ensures fast polarization response and significantly improves energy storage characteristics. A flexible BiFeO3-BaTiO3 (BF-BT) capacitor exhibits a total energy density of 43.5 J cm-3 and an efficiency of 66.7% and maintains good energy storage performance over a wide temperature range (20-200 °C) and under large bending deformation (bending radii ≈ 2 mm). This study provides a feasible approach to improve the energy storage characteristics of dielectric oxide films and paves the way for their practical application in high-energy density capacitors.

13.
Sci Rep ; 14(1): 15684, 2024 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977919

RESUMO

The global spread of COVID-19 has profoundly affected health and economies, highlighting the need for precise epidemic trend predictions for effective interventions. In this study, we used infectious disease models to simulate and predict the trajectory of COVID-19. An SEIR (susceptible, exposed, infected, removed) model was established using Wuhan data to reflect the pandemic. We then trained a genetic algorithm-based SEIR (GA-SEIR) model using data from a specific U.S. region and focused on individual susceptibility and infection dynamics. By integrating socio-psychological factors, we achieved a significant enhancement to the GA-SEIR model, leading to the development of an optimized version. This refined GA-SEIR model significantly improved our ability to simulate the spread and control of the epidemic and to effectively track trends. Remarkably, it successfully predicted the resurgence of COVID-19 in mainland China in April 2023, demonstrating its robustness and reliability. The refined GA-SEIR model provides crucial insights for public health authorities, enabling them to design and implement proactive strategies for outbreak containment and mitigation. Its substantial contributions to epidemic modelling and public health planning are invaluable, particularly in managing and controlling respiratory infectious diseases such as COVID-19.


Assuntos
Algoritmos , COVID-19 , COVID-19/epidemiologia , COVID-19/virologia , COVID-19/psicologia , Humanos , China/epidemiologia , SARS-CoV-2 , Pandemias , Estados Unidos/epidemiologia
14.
Biomed Chromatogr ; 38(9): e5932, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38922712

RESUMO

Abnormal relaxation and contraction of intestinal smooth muscle can cause various intestinal diseases. Diarrhea is a common and important public health problem worldwide in epidemiology. Zingiber officinale Roscoe (fresh ginger) has been found to treat diarrhea, but the material basis and mechanism of action that inhibits intestinal peristalsis remain unclear. Metabolomics and serum pharmacology were used to identify differential metabolites, metabolic pathways, and pharmacodynamic substances, and were then combined with network pharmacology to explore the potential targets of ginger that inhibit intestinal peristalsis during diarrhea treatment, and the targets identified were verified using molecular docking and molecular dynamic simulation. We found that 25 active components of ginger (the six most relevant components), 35 potential key targets (three core targets), 40 differential metabolites (four key metabolites), and four major metabolic pathways were involved in the process by which ginger inhibits intestinal peristalsis during diarrhea treatment. This study reveals the complex mechanism of action and pharmacodynamic material basis of ginger in the inhibition of intestinal peristalsis, and this information helps in the development of new Chinese medicine to treat diarrhea and lays the foundation for the clinical application of ginger.


Assuntos
Metabolômica , Simulação de Acoplamento Molecular , Farmacologia em Rede , Peristaltismo , Zingiber officinale , Zingiber officinale/química , Metabolômica/métodos , Animais , Peristaltismo/efeitos dos fármacos , Masculino , Diarreia/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Metaboloma/efeitos dos fármacos , Metaboloma/fisiologia , Intestinos/efeitos dos fármacos
15.
J Neurosurg Spine ; 41(3): 316-324, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38905714

RESUMO

OBJECTIVE: There is still controversy about whether it is necessary to perform prophylactic neurosurgical decompression for severe scoliosis (SS) with syringomyelia (SM) to reduce the risk of neurological complications during subsequent spinal correction. This study aimed to explore the safety and effectiveness of using traction-assisted single-stage spinal correction as a treatment for patients who had SS with SM (SS-SM). METHODS: The patients who had SS-SM without previous neurosurgical intervention and who underwent traction-assisted single-stage posterior spinal correction at a single center were included, and the initial, posttraction, and postoperative clinical data were reviewed. Based on preoperative MRI, the included patients were divided into two categories: those with versus those without Chiari malformation type I (CM-I-related SM [CS] vs idiopathic SM [IS]), and those with a moderate syrinx (MS) versus those with a large syrinx (LS). Different groups' traction and operation contributions were calculated for comparisons (CS vs IS, MS vs LS). RESULTS: A total of 28 patients were included. The initial mean major scoliosis was 101.0° with a mean flexibility of 21.4%. After the operation, the mean total correction rate for scoliosis was 63.9%. The mean traction and operation contributions were 61.5% and 38.5%, respectively. Most of the patients (75%) underwent spinal corrections without 3-column osteotomies, and only 1 patient reported postoperative regional numbness without motor deficits. No differences were found in the mean total correction rates, traction, and operation contributions when comparing CS versus IS and MS versus LS with the comparable initial clinical data (p > 0.05). More than 50% of the total corrections were achieved by preoperative traction in all groups. CONCLUSIONS: Traction-assisted single-stage spinal correction can safely and effectively correct SS-SM without prophylactic neurosurgical decompression under strict patient selection. Additionally, traction can achieve more than half of the final spinal correction, even for patients with varying sizes of SMs.


Assuntos
Descompressão Cirúrgica , Escoliose , Siringomielia , Tração , Humanos , Escoliose/cirurgia , Siringomielia/cirurgia , Feminino , Masculino , Tração/métodos , Adolescente , Descompressão Cirúrgica/métodos , Resultado do Tratamento , Adulto , Adulto Jovem , Malformação de Arnold-Chiari/cirurgia , Malformação de Arnold-Chiari/complicações , Criança , Fusão Vertebral/métodos , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Procedimentos Neurocirúrgicos/métodos
16.
Nat Commun ; 15(1): 4905, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851776

RESUMO

The moiré potential serves as a periodic quantum confinement for optically generated excitons, creating spatially ordered zero-dimensional quantum systems. However, a broad emission spectrum resulting from inhomogeneity among moiré potentials hinders the investigation of their intrinsic properties. In this study, we demonstrated a method for the optical observation of quantum coherence and interference of a single moiré exciton in a twisted semiconducting heterobilayer beyond the diffraction limit of light. We observed a single and sharp photoluminescence peak from a single moiré exciton following nanofabrication. Our findings revealed the extended duration of quantum coherence in a single moiré exciton, persisting beyond 10 ps, and an accelerated decoherence process with increasing temperature and excitation power density. Moreover, quantum interference experiments revealed the coupling between moiré excitons in different moiré potential minima. The observed quantum coherence and interference of moiré exciton will facilitate potential applications of moiré quantum systems in quantum technologies.

18.
Trials ; 25(1): 352, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822360

RESUMO

BACKGROUND: Knee osteoarthritis (KOA) is a chronic musculoskeletal disorder characterized by pain and functional impairment. Blood flow restriction (BFR) with low-load resistance training (LLRT) demonstrates a similar improvement in clinical outcomes to high-load resistance training (HLRT) in treating KOA. It has not been established whether intermittent blood flow restriction (iBFR) with LLRT can lead to clinical outcomes that are comparable to those produced by continuous blood flow restriction (cBFR) with LLRT and HLRT. The aim of the proposed study is to evaluate the efficacy of iBFR with LLRT on pain, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), muscle strength, muscle mass, physical function, perceptions of discomfort and effort, and adherence in KOA patients. METHODS: This is a three-arm, non-inferiority, randomized controlled trial utilizing blinded assessors. Two hundred thirteen participants will be randomly allocated to one of the following three groups: iBFR group-receiving 4 months of LLRT with iBFR, twice weekly (n = 71); cBFR group-receiving 4 months of LLRT with cBFR, twice weekly (n = 71); or HLRT group-receiving 4 months of HLRT without BFR, twice weekly (n = 71). The primary outcome is pain. The secondary outcomes include the WOMAC, muscle strength, muscle mass, physical function, perceptions of discomfort and effort, and adherence. Pain and WOMAC will be measured at the baseline and 4 and 12 months after randomizations. Muscle strength, muscle mass, and physical function will be measured at the baseline and 4 months after randomizations. The perceptions of discomfort and effort will be measured during the first and final sessions. DISCUSSION: BFR with LLRT has a similar improvement in clinical outcomes as HLRT. However, cBFR may cause elevated ratings of perceived exertion and local discomfort, compromising patient tolerability and treatment adherence. If iBFR with LLRT could produce improvement in clinical outcomes analogous to those of HLRT and iBFR with LLRT, it could be considered an alternative approach for treating patients with KOA. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2300072820. Registered on June 26, 2023.


Assuntos
Terapia de Restrição de Fluxo Sanguíneo , Força Muscular , Osteoartrite do Joelho , Treinamento Resistido , Humanos , Treinamento Resistido/métodos , Osteoartrite do Joelho/fisiopatologia , Osteoartrite do Joelho/terapia , Idoso , Resultado do Tratamento , Terapia de Restrição de Fluxo Sanguíneo/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos de Equivalência como Asunto , Medição da Dor , Fluxo Sanguíneo Regional , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Fatores de Tempo , Articulação do Joelho/fisiopatologia
19.
Front Physiol ; 15: 1404247, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38911327

RESUMO

Purpose: The blood flow restriction (BFR) training is an effective approach to promoting muscle strength, muscle hypertrophy, and regulating the peripheral vascular system. It is recommended to use to the percentage of individual arterial occlusion pressure (AOP) to ensure safety and effectiveness. The gold standard method for assessing arterial occlusive disease is typically measured using Doppler ultrasound. However, its high cost and limited accessibility restrict its use in clinical and practical applications. A novel wearable BFR training device (Airbands) with automatic AOP assessment provides an alternative solution. This study aims to examine the reliability and validity of the wearable BFR training device. Methods: Ninety-two participants (46 female and 46 male) were recruited for this study. Participants were positioned in the supine position with the wearable BFR training device placed on the proximal portion of the right thigh. AOP was measured automatically by the software program and manually by gradually increasing the pressure until the pulse was no longer detected by color Doppler ultrasound, respectively. Validity, inter-rater reliability, and test-retest reliability were assessed by intraclass correlation coefficients (ICC) and Bland-Altman analysis. Results: The wearable BFR training device demonstrated good validity (ICC = 0.85, mean difference = 4.1 ± 13.8 mmHg [95% CI: -23.0 to 31.2]), excellent inter-rater reliability (ICC = 0.97, mean difference = -1.4 ± 6.7 mmHg [95% CI: -14.4 to 11.7]), and excellent test-retest reliability (ICC = 0.94, mean difference = 0.6 ± 8.6 mmHg [95% CI: -16.3 to 17.5]) for the assessment of AOP. These results were robust in both male and female subgroups. Conclusion: The wearable BFR training device can be used as a valid and reliable tool to assess the AOP of the lower limb in the supine position during BFR training.

20.
Sci Bull (Beijing) ; 69(13): 2042-2049, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38824120

RESUMO

Owing to the outstanding properties provided by nontrivial band topology, topological phases of matter are considered as a promising platform towards low-dissipation electronics, efficient spin-charge conversion, and topological quantum computation. Achieving ferroelectricity in topological materials enables the non-volatile control of the quantum states, which could greatly facilitate topological electronic research. However, ferroelectricity is generally incompatible with systems featuring metallicity due to the screening effect of free carriers. In this study, we report the observation of memristive switching based on the ferroelectric surface state of a topological semimetal (TaSe4)2I. We find that the surface state of (TaSe4)2I presents out-of-plane ferroelectric polarization due to surface reconstruction. With the combination of ferroelectric surface and charge-density-wave-gapped bulk states, an electric-switchable barrier height can be achieved in (TaSe4)2I-metal contact. By employing a multi-terminal-grounding design, we manage to construct a prototype ferroelectric memristor based on (TaSe4)2I with on/off ratio up to 103, endurance over 103 cycles, and good retention characteristics. The origin of the ferroelectric surface state is further investigated by first-principles calculations, which reveal an interplay between ferroelectricity and band topology. The emergence of ferroelectricity in (TaSe4)2I not only demonstrates it as a rare but essential case of ferroelectric topological materials, but also opens new routes towards the implementation of topological materials in functional electronic devices.

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