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1.
Langmuir ; 2024 Oct 03.
Article de Anglais | MEDLINE | ID: mdl-39360777

RÉSUMÉ

Creating and unveiling chiral systems is important to the development of new materials and devices. In this study, after depositing prochiral radical molecule 3-carbamoyl-2,2,5,5-tetramethyl pyrroline-1-oxyl (CTPO) on a Au(111) substrate, 2D molecular crystals with two chiralities of CTPO molecules have been discovered. A single CTPO molecule is an achiral molecule in three-dimensional space, and it can form chiral configurations after adsorbing on the substrate. The chiralities of 2D molecular crystals originate from the chiral properties of adsorbed CTPO molecules and their assembling. Molecules with different chiralities are connected with molecular recognition through hydrogen bond interactions. Through density functional theory simulations, the hydrogen bond networks and molecular structures of this system were explored. To gain a further understanding of this system, the electronic property of CTPO/Au(111) was studied with a local density of states (LDOS) characterization. A peculiar LDOS distribution related to the vibrational excitation of the molecules was mapped at the submolecular scale. These results are useful for understanding the nature of chirality formation, 2D molecular crystal construction, and radical molecule applications.

2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(9): 1117-1123, 2024 Sep 10.
Article de Chinois | MEDLINE | ID: mdl-39217493

RÉSUMÉ

OBJECTIVE: To explore the genetic basis for a child with developmental delay and intellectual deficit (DD/ID). METHODS: A child who was admitted to the Maternal and Child Health Care Hospital of Longhua District of Shenzhen City on June 3, 2023 due to DD/ID, craniofacial malformations, and recurrent infections of upper respiratory tract was selected as the study subject. G-banded chromosomal karyotyping was carried out for the child and her parents. Low-depth genome-wide copy number variation sequencing (CNV-seq) and chromosomal microarray analysis (CMA) were used to screen for genome-wide copy number variations (CNV), and fluorescence in situ hybridization (FISH) was used to verify the origin of candidate CNV. RESULTS: The child, an 8-year-old girl, had featured unexplained growth and intellectual development delay, multiple craniofacial malformations, and recurrent infections of the upper respiratory tract. She was found to have a karyotype of 46,XX,der(6)add(6)(q23), while both of her parents were normal. Both CNV-seq and CMA showed that the child has harbored a 21.38 Mb interstitial duplication at 6p25.3p22.3 and a 0.78 Mb terminal deletion at 6p25. FISH verified that both the duplication and deletion had occurred de novo. CONCLUSION: The abnormal phenotype of the child may be attributed to the 6p duplication and terminal deletion.


Sujet(s)
Délétion de segment de chromosome , Variations de nombre de copies de segment d'ADN , Phénotype , Humains , Femelle , Enfant , Chromosomes humains de la paire 6/génétique , Caryotypage , Déficience intellectuelle/génétique , Incapacités de développement/génétique , Hybridation fluorescente in situ , Duplication chromosomique
3.
Acta Bioeng Biomech ; 26(1): 23-35, 2024 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-39219086

RÉSUMÉ

Purpose: Iliac vein stenting is the primary treatment for patients with iliac vein compression syndrome (IVCS). However, post-stent placement, patients often experience in-stent restenosis and thrombosis. Despite this, the role of lower limb movements in the functioning of stents and veins in IVCS patients remains unclear. This study aimed to address this knowledge gap by developing a computational model using medical imaging techniques to simulate IVCS after stent placement. Methods: This research used a patient-specific model to analyze the effects of lower extremity exercises on hemodynamics post-stent placement. We conducted a comprehensive analysis to evaluate the impact of specific lower limb movements, including hip flexion, ankle movement and pneumatic compression on the hemo-dynamic characteristics within the treated vein. The analysis assessed parameters such as wall shear stress (WSS), oscillatory shear index (OSI), and residence time (RRT). Results: The results demonstrated that hip flexion significantly disrupts blood flow dynamics at the iliac vein bifurcation after stenting. Bilateral and left hip flexion were associated with pronounced regions of low WSS and high OSI at the iliac-vena junction and the stent segment. Additionally, active ankle exercise (AAE) and intermittent pump compression (IPC) therapy were found to enhance the occurrence of low WSS regions along the venous wall, potentially reducing the risk of thrombosis post-stent placement. Consequently, both active joint movements (hip and ankle) and passive movements have the potential to influence the local blood flow environment within the iliac vein after stenting. Conclusions: The exploration of the impact of lower limb movements on hemodynamics provides valuable insights for mitigating adverse effects associated with lower limb movements post iliac-stenting. Bilateral and left hip flexions negatively impacted blood flow, increasing thrombosis risk. However, active ankle exercise and intermittent pump compression therapies effectively improve the patency.


Sujet(s)
Veine iliaque commune , Membre inférieur , Syndrome de May-Thurner , Endoprothèses , Humains , Veine iliaque commune/physiopathologie , Syndrome de May-Thurner/physiopathologie , Syndrome de May-Thurner/thérapie , Membre inférieur/physiopathologie , Membre inférieur/vascularisation , Simulation numérique , Mouvement/physiologie , Contrainte mécanique , Hémodynamique/physiologie , Modèles cardiovasculaires
5.
Ecol Evol ; 14(9): e70314, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39279795

RÉSUMÉ

The global climate change has resulted in substantial modifications to the distribution patterns of narrowly distributed species across different time periods, leading to an imminent threat to the survival of some vulnerable species. Chimonobambusa tumidissinoda J. R. Xue & T. P. Yi ex Ohrnb., a bamboo species endemic to the transition zone from the Yunnan-Guizhou Plateau to the Sichuan Basin with high economic and ecological value, exhibits a limited range and rarity. Utilizing eight environmental variables and 56 occurrence records, we employed the MaxEnt model to predict the potential distribution range of C. tumidissinoda under current and future climate scenarios. The findings revealed that precipitation of the driest month (Bio14), elevation and isothermality (Bio3) were the crucial factors determining the species' distribution, accounting for 31.24%, 28.27% and 17.24% of data variability, respectively. The distribution centroid of C. tumidissinoda is anticipated to shift towards higher latitudes in response to future climate change, and the projected habitat suitability is expected to expand under ssp245 and ssp585 scenarios while remaining unchanged or contracting under the ssp126 scenario. Despite these expansions, the suitable habitats remain limited, with the largest being approximately 2.08 × 104 km2, indicating a significant threat to its survival. Our study provides insights into the adaptive responses of C. tumidissinoda to climate change, enriching scientific knowledge for developing effective conservation measurements as well as sustainable utilization.

6.
Med Phys ; 2024 Sep 10.
Article de Anglais | MEDLINE | ID: mdl-39255333

RÉSUMÉ

BACKGROUND: Residual stenosis (RS) and hemodynamics demonstrate a significant correlation with postoperative in-stent restenosis/thrombosis following carotid artery stenting (CAS). PURPOSE: This study endeavors to elucidate the potential associations between RS and adverse postoperative hemodynamic factors. METHODS: This study utilized 46 patient-specific carotid artery models post-stenting, which were categorized into two groups based on the presence of RS: the normal group (N, n = 23) and the RS group (RS, n = 23). A comparative analysis was conducted to evaluate the discrepancies in geometry and adverse hemodynamic parameters, alongside investigating the potential correlation between hemodynamic and geometric parameters. RESULTS: The results reveal that a higher reflux flow volume is discernible in the RS group during low-velocity phases of the cardiac cycle, concomitant with an augmented extent of areas exposed to oscillatory shear stress and extended particle residence time. Moreover, the adverse hemodynamic parameters exhibit a positive correlation with the degree of stent expansion, stent length in the common carotid artery (CCA), and the distal slope of the RS. CONCLUSION: The distal slope and tortuosity of RS significantly influence the development of adverse hemodynamic conditions post-stenting, exacerbating the hemodynamic environment near the stenosis. Interestingly, while an extended stent length in the internal carotid artery (ICA) region improves hemodynamics by reducing flow disturbance, a longer stent in the CCA significantly worsens these conditions. Hence, it is prudent to analyze the characteristics of the local lesion regions to optimize the strategy for stent implantation.

7.
Front Neurorobot ; 18: 1442080, 2024.
Article de Anglais | MEDLINE | ID: mdl-39323931

RÉSUMÉ

Physiological signal recognition is crucial in emotion recognition, and recent advancements in multi-modal fusion have enabled the integration of various physiological signals for improved recognition tasks. However, current models for emotion recognition with hyper complex multi-modal signals face limitations due to fusion methods and insufficient attention mechanisms, preventing further enhancement in classification performance. To address these challenges, we propose a new model framework named Signal Channel Attention Network (SCA-Net), which comprises three main components: an encoder, an attention fusion module, and a decoder. In the attention fusion module, we developed five types of attention mechanisms inspired by existing research and performed comparative experiments using the public dataset MAHNOB-HCI. All of these experiments demonstrate the effectiveness of the attention module we addressed for our baseline model in improving both accuracy and F1 score metrics. We also conducted ablation experiments within the most effective attention fusion module to verify the benefits of multi-modal fusion. Additionally, we adjusted the training process for different attention fusion modules by employing varying early stopping parameters to prevent model overfitting.

8.
J Theor Biol ; 595: 111929, 2024 Aug 26.
Article de Anglais | MEDLINE | ID: mdl-39197677

RÉSUMÉ

Vascular stent intervention is a pivotal treatment for coronary atherosclerosis, though in-stent thrombosis remains a significant postoperative complication with an unclear underlying mechanism. This study utilized dissipated particle dynamics analysis to investigate the impact of stent and its injury on platelet behavior. The findings suggest that thrombus formation upstream of the stent is mainly initiated by upstream arterial injury, which leads to increased platelet accumulation and activation in that area. While thrombosis downstream of the stent is more directly influenced by the stent itself. The morphology and size of in-stent thrombosis can vary significantly due to the different contributions of the stent and underlying injuries. Additionally, the volume of in-stent thrombosis is affected by the extent of the injury and the viscosity of platelets, showing a notable increase in volume with the lengthening of the injury area and rise in platelet viscosity. This study provides a novel theoretical framework for optimizing stent placement strategies and structural designs by examining the effects of stent struts and associated injuries on thrombus formation.

9.
Hortic Res ; 11(7): uhae155, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39005999

RÉSUMÉ

Stable genetic transformation of peach [Prunus persica (L.) Batsch] still faces many technical challenges, and existing transient expression methods are limited by tissue type or developmental stage, making it difficult to conduct functional analysis of genes regulating shoot growth. To overcome this dilemma, we developed a three-step method for efficient analysis of gene functions during peach seedling growth and development. This method resulted in transformation frequencies ranging from 48 to 87%, depending on the gene. From transformation of germinating seeds to phenotyping of young saplings took just 1.5 months and can be carried out any time of year. To test the applicability of this method, the function of three tree architecture-related genes, namely PpPDS, PpMAX4, and PpWEEP, and two lateral root-related genes, PpIAA14-1 and -2, were confirmed. Since functional redundancy can challenge gene functional analyses, tests were undertaken with the growth-repressor DELLA, which has three homologous genes, PpDGYLA (DG), PpDELLA1 (D1), and -2 (D2), in peach that are functionally redundant. Silencing using a triple-target vector (TRV2-DG-D1-D2) resulted in transgenic plants taller than those carrying just TRV2-DG or TRV2. Simultaneously silencing the three DELLA genes also attenuated the stature of two dwarf genotypes, 'FHSXT' and 'HSX', which normally accumulate DELLA proteins. Our study provides a method for the functional analysis of genes in peach and can be used for the study of root, stem, and leaf development. We believe this method can be replicated in other woody plants.

10.
Chem Sci ; 15(28): 10989-10996, 2024 Jul 17.
Article de Anglais | MEDLINE | ID: mdl-39027270

RÉSUMÉ

The discovery of negative differential conductance (NDC) in a single molecule and mechanism controlling this phenomenon are important for molecular electronics. We investigated the electronic properties of a typical radical molecule 3-carbamoyl-2,2,5,5-tetramethyl-3-pyrrolin-1-yloxy (CTPO) on an Au(111) surface using low-temperature scanning tunneling microscopy (STM) and inelastic electron tunneling spectroscopy. Large NDC was observed in single CTPO molecules at the boundary of the crystal monolayer. The origin of observed NDC is revealed as the inelastic electron-phonon scattering during tunneling, and the strong spatial variation of the NDC over the single molecule illustrates the nature of the localized radical group. In addition, the NDC can be transformed into a positive differential conductance peak by tuning coupling strengths between different tunneling channels. An empirical multi-channel model has been developed to describe the competition between the valley-shaped NDC and peak-shaped positive differential conductance. The unique electronic property and giant conductance change observed in this radical molecule is valuable for designing novel molecular devices in the future.

11.
Sensors (Basel) ; 24(13)2024 Jun 24.
Article de Anglais | MEDLINE | ID: mdl-39000877

RÉSUMÉ

In complex environments a single visible image is not good enough to perceive the environment, this paper proposes a novel dual-stream real-time detector designed for target detection in extreme environments such as nighttime and fog, which is able to efficiently utilise both visible and infrared images to achieve Fast All-Weatherenvironment sensing (FAWDet). Firstly, in order to allow the network to process information from different modalities simultaneously, this paper expands the state-of-the-art end-to-end detector YOLOv8, the backbone is expanded in parallel as a dual stream. Then, for purpose of avoid information loss in the process of network deepening, a cross-modal feature enhancement module is designed in this study, which enhances each modal feature by cross-modal attention mechanisms, thus effectively avoiding information loss and improving the detection capability of small targets. In addition, for the significant differences between modal features, this paper proposes a three-stage fusion strategy to optimise the feature integration through the fusion of spatial, channel and overall dimensions. It is worth mentioning that the cross-modal feature fusion module adopts an end-to-end training approach. Extensive experiments on two datasets validate that the proposed method achieves state-of-the-art performance in detecting small targets. The cross-modal real-time detector in this study not only demonstrates excellent stability and robust detection performance, but also provides a new solution for target detection techniques in extreme environments.

12.
New Phytol ; 243(3): 1050-1064, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38872462

RÉSUMÉ

Branch number is one of the most important agronomic traits of fruit trees such as peach. Little is known about how LncRNA and/or miRNA modules regulate branching through transcription factors. Here, we used molecular and genetic tools to clarify the molecular mechanisms underlying brassinosteroid (BR) altering plant branching. We found that the number of sylleptic branch and BR content in pillar peach ('Zhaoshouhong') was lower than those of standard type ('Okubo'), and exogenous BR application could significantly promote branching. PpTCP4 expressed great differentially comparing 'Zhaoshouhong' with 'Okubo'. PpTCP4 could directly bind to DWARF2 (PpD2) and inhibited its expression. PpD2 was the only one differentially expressed key gene in the path of BR biosynthesis. At the same time, PpTCP4 was identified as a target of miR6288b-3p. LncRNA1 could act as the endogenous target mimic of miR6288b-3p and repress expression of miR6288b-3p. Three deletions and five SNP sites of lncRNA1 promoter were found in 'Zhaoshouhong', which was an important cause of different mRNA level of PpTCP4 and BR content. Moreover, overexpressed PpTCP4 significantly inhibited branching. A novel mechanism in which the lncRNA1-miR6288b-3p-PpTCP4-PpD2 module regulates peach branching number was proposed.


Sujet(s)
Brassinostéroïdes , Régulation de l'expression des gènes végétaux , microARN , Protéines végétales , Prunus persica , ARN long non codant , ARN long non codant/génétique , ARN long non codant/métabolisme , microARN/génétique , microARN/métabolisme , Prunus persica/génétique , Prunus persica/croissance et développement , Prunus persica/métabolisme , Brassinostéroïdes/métabolisme , Brassinostéroïdes/biosynthèse , Protéines végétales/génétique , Protéines végétales/métabolisme , Régions promotrices (génétique)/génétique , Séquence nucléotidique , Polymorphisme de nucléotide simple/génétique , Gènes de plante
13.
Plant Mol Biol ; 114(3): 46, 2024 Apr 17.
Article de Anglais | MEDLINE | ID: mdl-38630415

RÉSUMÉ

Peach fruit rapidly soften after harvest, a significant challenge for producers and marketers as it results in rotting fruit and significantly reduces shelf life. In this study, we identified two tandem genes, PpNAC1 and PpNAC5, within the sr (slow ripening) locus. Phylogenetic analysis showed that NAC1 and NAC5 are highly conserved in dicots and that PpNAC1 is the orthologous gene of Non-ripening (NOR) in tomato. PpNAC1 and PpNAC5 were highly expressed in peach fruit, with their transcript levels up-regulated at the onset of ripening. Yeast two-hybrid and bimolecular fluorescence complementation assays showed PpNAC1 interacting with PpNAC5 and this interaction occurs with the tomato and apple orthologues. Transient gene silencing experiments showed that PpNAC1 and PpNAC5 positively regulate peach fruit softening. Yeast one-hybrid and dual luciferase assays and LUC bioluminescence imaging proved that PpNAC1 and PpNAC5 directly bind to the PpPGF promoter and activate its transcription. Co-expression of PpNAC1 and PpNAC5 showed higher levels of PpPGF activation than expression of PpNAC1 or PpNAC5 alone. In summary, our findings demonstrate that the tandem transcription factors PpNAC1 and PpNAC5 synergistically activate the transcription of PpPGF to regulate fruit softening during peach fruit ripening.


Sujet(s)
Prunus persica , Solanum lycopersicum , Prunus persica/génétique , Fruit/génétique , Phylogenèse , Saccharomyces cerevisiae , Solanum lycopersicum/génétique , Facteurs de transcription/génétique
14.
Skin Res Technol ; 30(4): e13671, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38558153

RÉSUMÉ

BACKGROUND: Nowadays, diabetic wound healing remains a crucial challenge due to their protracted and uncertain healing process. Traditional Chinese medicine (TCM) has demonstrated the therapeutic value of Sanguis draconis (SD)-Salvia miltiorrhiza (SMR) Herb Pair in diabetic wound healing. However, new administration modes are urgently needed for their convenient and wide-ranging applications. OBJECTIVE: We propose a soluble polyvinylpyrrolidone-based microneedle patch containing the herbal extracts of SD and SMR (MN-SD@SMR) for diabetic wound healing. METHODS: The herbal extracts of SD and SMR are purification and concentration via traditional lyophilization. SD endowed MN-SD@SMR with functions to improve high glycemic blood environment and migration of keratinocyte and fibroblast cells. RESULTS: SMR in MN-SD@SMR could improve blood flow velocity and microcirculation in the wound area. The effectiveness of transdermal release and mechanical strengths of MN-SD@SMR were verified. CONCLUSION: Integrating the advantages of these purified herbal compositions, we demonstrated that MN-SD@SMR had a positive healing effect on the wounds in vitro and vivo. These results indicate that soluble polyvinylpyrrolidone-based microneedle patch containing the herbal extracts of SD and SMR has a promising application value due to their superior capability to promote diabetic wound healing.


Sujet(s)
Diabète , Médicaments issus de plantes chinoises , Salvia miltiorrhiza , Humains , Povidone , Diabète/traitement médicamenteux , Cicatrisation de plaie
15.
Nat Genet ; 56(4): 710-720, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38491323

RÉSUMÉ

Polyploidy (genome duplication) is a pivotal force in evolution. However, the interactions between parental genomes in a polyploid nucleus, frequently involving subgenome dominance, are poorly understood. Here we showcase analyses of a bamboo system (Poaceae: Bambusoideae) comprising a series of lineages from diploid (herbaceous) to tetraploid and hexaploid (woody), with 11 chromosome-level de novo genome assemblies and 476 transcriptome samples. We find that woody bamboo subgenomes exhibit stunning karyotype stability, with parallel subgenome dominance in the two tetraploid clades and a gradual shift of dominance in the hexaploid clade. Allopolyploidization and subgenome dominance have shaped the evolution of tree-like lignified culms, rapid growth and synchronous flowering characteristic of woody bamboos as large grasses. Our work provides insights into genome dominance in a remarkable polyploid system, including its dependence on genomic context and its ability to switch which subgenomes are dominant over evolutionary time.


Sujet(s)
Poaceae , Tétraploïdie , Poaceae/génétique , Polyploïdie , Génomique , Transcriptome/génétique , Génome végétal/génétique , Évolution moléculaire
16.
Inorg Chem ; 63(14): 6514-6525, 2024 Apr 08.
Article de Anglais | MEDLINE | ID: mdl-38547361

RÉSUMÉ

The solar light-responsive Fe-doped Co-based coordination polymer (Fe@Co-CP) photocatalyst was synthesized under mild conditions. [Co(4-padpe)(1,3-BDC)]n (Co-CP) was first constructed using mixed ligands through the hydrothermal method. Then, Fe was introduced into the Co-CP framework to achieve the enhanced photocatalytic activity. The optimal Fe@Co-CP-2 exhibited excellent catalytic degradation performance for norfloxacin and ciprofloxacin under sunlight irradiation without auxiliary oxidants, and the degradation rates were 91.25 and 92.66% in 120 min. These excellent photocatalytic properties were ascribed to the generation of the Fe-O bond, which not only enhanced the light absorption intensity but also accelerated the separation efficiency of electrons and holes, and hence significantly improved the photocatalytic property of the composites. Meanwhile, Fe@Co-CP-2 displayed excellent stability and reusability. In addition, the degradation pathways and intermediates of antibiotic molecules were effectively analyzed. The free radical scavenging experiment and ESR results confirmed that •OH, •O2-, and h+ active species were involved in the catalytic degradation reaction; the corresponding mechanisms were deeply investigated. This study provides a fresh approach for constructing Fe-doped Co-CP-based composite materials as photocatalysts for degradation of antibiotic contaminants.


Sujet(s)
Ciprofloxacine , Norfloxacine , Norfloxacine/composition chimique , Norfloxacine/effets des radiations , Antibactériens/composition chimique , Lumière , Catalyse
17.
Protoplasma ; 261(4): 819-830, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38418654

RÉSUMÉ

Transient transformation is extremely useful for rapid in vivo assessment of gene function, especially for fruit-related genes. Grape berry, while an important fruit crop, is recalcitrant to transient transformation, due to the high turgor pressure in its mesocarp cells that limits the ability of Agrobacterium to penetrate into the tissue. It is urgent to establish a simple transient transformation system for rapid analysis of gene function. In this study, different injection methods, grape genotypes, and developmental stages were tested in order to develop a rapid and efficient Agrobacterium-mediated transient transformation methodology for grape berries. Two injection methods, namely punch injection and direct injection, were evaluated using the ß-glucuronidase (GUS) gene and by x-gluc tissue staining and 4-methylumbelliferyl-ß-D-glucuronide fluorescence analysis. The results indicated that there were no significant differences on transformation effects between the two methods, but the latter was more suitable because of its simplicity and convenience. Six grape cultivars ('Hanxiangmi', 'Moldova', 'Zijixin', 'Jumeigui', 'Shine-Muscat', and 'A17') were tested for transient transformation. 'Hanxiangmi', 'Moldova', and 'Zijixin' grape berries were not suitable for agroinfiltration due to frequently fruit cracking, browning, and formation of scar skin. The fruit integrity rates of 'Jumeigui', 'Shine-Muscat', and 'A17' berries were all above 80%, and GUS activity was detected in the berries of the three cultivars 3-14 days after injection with the Agrobacterium culture, while higher GUS activities were observed in the 'Jumeigui' berries. The levels of GUS activity in injected berries at 7-8 weeks after full blooming (WAFB) were more than twice at 6 WAFB. In subsequent assays, the over-expression of MYB transcription factor VvMYB44 via transient transformation accelerated the anthocyanin accumulation and fruit coloring through raising the expression levels of VvLAR1, VvUFGT, VvLDOX, VvANS, and VvDFR, which verified the effectiveness of this transformation system. These experiments finally identified the reliable grape cultivars and suitable operational approach for transient transformation and further indicated that this Agrobacterium-mediated transient transformation system was efficient and suitable for the elucidation of gene function in grape berries.


Sujet(s)
Agrobacterium , Fruit , Végétaux génétiquement modifiés , Transformation génétique , Vitis , Vitis/génétique , Vitis/métabolisme , Agrobacterium/génétique
18.
J Theor Biol ; 582: 111758, 2024 04 07.
Article de Anglais | MEDLINE | ID: mdl-38336241

RÉSUMÉ

BACKGROUND: Stent implantation is a highly efficacious intervention for the treatment of coronary atherosclerosis. Nevertheless, stent thrombosis and other post-operative complications persist, and the underlying mechanism of adverse event remains elusive. METHODS: In the present study, a dissipative particle dynamics model was formulated to simulate the motion, adhesion, activation, and aggregation of platelets, with the aim of elucidating the mechanisms of in-stent thrombosis. FINDINGS: The findings suggest that stent thrombosis arises from a complex interplay of multiple factors, including endothelial injury resulting from stent implantation and alterations in the hemodynamic milieu. Furthermore, the results suggest a noteworthy association between in-stent thrombosis and both the length of the endothelial injured site and the degree of stent malposition. Specifically, the incidence of stent thrombosis appears to rise in tandem with the extent of the injured site, while moderate stent malposition is more likely to result in in-stent thrombosis compared to severe or minor malposition. INTERPRETATION: This study offers novel research avenues for investigating the plasticity mechanism of stent thrombosis, while also facilitating the clinical prediction of stent thrombosis formation and the development of more precise treatment strategies.


Sujet(s)
Endoprothèses , Thrombose , Humains , Endoprothèses/effets indésirables , Plaquettes , Thrombose/étiologie
19.
Article de Anglais | MEDLINE | ID: mdl-38261605

RÉSUMÉ

OBJECTIVES: Rheumatoid arthritis (RA) is characterized by hypoxia in the synovial tissue. While photoacoustic imaging (PA) offers a method to evaluate tissue oxygenation in RA patients, studies exploring the link between extra-synovial tissue of wrist oxygenation and disease activity remain scarce. We aimed to assess synovial oxygenation in RA patients using a multimodal photoacoustic-ultrasound (PA/US) imaging system and establish its correlation with disease activity. METHODS: A retrospective study was conducted on 111 patients with RA and 72 healthy controls from 2022 to 2023. Dual-wavelength PA imaging quantified oxygen saturation (So2) levels in the synovial membrane and peri-wrist region. Oxygenation states were categorised as hyperoxia, intermediate oxygenation, and hypoxia based on So2 values. The association between oxygenation levels and the clinical disease activity index was evaluated using a one-way analysis of variance, complemented by the Kruskal-Wallis test with Bonferroni adjustment. RESULTS: Of the patients with RA, 39 exhibited hyperoxia, 24 had intermediate oxygenation, and 48 had hypoxia in the wrist extra-synovial tissue. All of the control participants exhibited the hyperoxia status. Oxygenation levels in patients with RA correlated with clinical metrics. Patients with intermediate oxygenation had a lower disease activity index compared with those with hypoxia and hyperoxia. CONCLUSION: A significant correlation exists between wrist extra-synovial tissue oxygenation and disease activity in patients with RA.

20.
Comput Biol Med ; 169: 107838, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38171259

RÉSUMÉ

To improve the detection of COVID-19, this paper researches and proposes an effective swarm intelligence algorithm-driven multi-threshold image segmentation (MTIS) method. First, this paper proposes a novel RIME structure integrating the Co-adaptive hunting and dispersed foraging strategies, called CDRIME. Specifically, the Co-adaptive hunting strategy works in coordination with the basic search rules of RIME at the individual level, which not only facilitates the algorithm to explore the global optimal solution but also enriches the population diversity to a certain extent. The dispersed foraging strategy further enriches the population diversity to help the algorithm break the limitation of local search and thus obtain better convergence. Then, on this basis, a new multi-threshold image segmentation method is proposed by combining the 2D non-local histogram with 2D Kapur entropy, called CDRIME-MTIS. Finally, the results of experiments based on IEEE CEC2017, IEEE CEC2019, and IEEE CEC2022 demonstrate that CDRIME has superior performance than some other basic, advanced, and state-of-the-art algorithms in terms of global search, convergence performance, and escape from local optimality. Meanwhile, the segmentation experiments on COVID-19 X-ray images demonstrate that CDRIME is more advantageous than RIME and other peers in terms of segmentation effect and adaptability to different threshold levels. In conclusion, the proposed CDRIME significantly enhances the global optimization performance and image segmentation of RIME and has great potential to improve COVID-19 diagnosis.


Sujet(s)
COVID-19 , Humains , Dépistage de la COVID-19 , Rayons X , Algorithmes , Entropie
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