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1.
Comput Methods Programs Biomed ; 249: 108142, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38547688

ABSTRACT

BACKGROUND AND OBJECTIVES: Virtual training has emerged as an exceptionally effective approach for training healthcare practitioners in the field of vascular intervention surgery. By providing a simulated environment and blood vessel model that enables repeated practice, virtual training facilitates the acquisition of surgical skills in a safe and efficient manner for trainees. However, the current state of research in this area is characterized by limitations in the fidelity of blood vessel and guidewire models, which restricts the effectiveness of training. Additionally, existing approaches lack the necessary real-time responsiveness and precision, while the blood vessel models suffer from incompleteness and a lack of scientific rigor. METHODS: To address these challenges, this paper integrates position-based dynamics (PBD) and its extensions, shape matching, and Cosserat elastic rods. By combining these approaches within a unified particle framework, accurate and realistic deformation simulation of personalized blood vessel and guidewire models is achieved, thereby enhancing the training experience. Furthermore, a multi-level progressive continuous collision detection method, leveraging spatial hashing, is proposed to improve the accuracy and efficiency of collision detection. RESULTS: Our proposed blood vessel model demonstrated acceptable performance with the reduced deformation simulation response times of 7 ms, improving the real-time capability at least of 43.75 %. Experimental validation confirmed that the guidewire model proposed in this paper can dynamically adjust the density of its elastic rods to alter the degree of bending and torsion. It also exhibited a deformation process comparable to that of real guidewires, with an average response time of 6 ms. In the interaction of blood vessel and guidewire models, the simulator blood vessel model used for coronary vascular intervention training exhibited an average response time of 15.42 ms, with a frame rate of approximately 64 FPS. CONCLUSIONS: The method presented in this paper achieves deformation simulation of both vascular and guidewire models, demonstrating sufficient real-time performance and accuracy. The interaction efficiency between vascular and guidewire models is enhanced through the unified simulation framework and collision detection. Furthermore, it can be integrated with virtual training scenarios within the system, making it suitable for developing more advanced vascular interventional surgery training systems.


Subject(s)
Virtual Reality , Computer Simulation , User-Computer Interface
2.
Analyst ; 149(3): 958-967, 2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38197472

ABSTRACT

Cortisol hormone imbalances can be detected through non-invasive sweat monitoring using field-effect transistor (FET) biosensors, which provide rapid and sensitive detection. However, challenges like skin compatibility and integration with sweat collection have hindered FET biosensors as wearable sensing platforms. In this study, we present an integrated wearable sticker for real-time cortisol detection based on an extended-gate AlGaN/GaN high electron mobility transistor (HEMT) combined with a soft bottom substrate and flexible channel for sweat collection. The developed devices exhibit excellent linearity (R2 = 0.990) and a high sensitivity of 1.245 µA dec-1 for cortisol sensing from 1 nM to 100 µM in high-ionic-strength solution, with successful cortisol detection demonstrated using authentic human sweat samples. Additionally, the chip's microminiature design effectively reduces bending impact during the wearable process of traditional soft binding sweat sensors. The extendedgate structure design of the HEMT chip enhances both width-to-length ratio and active sensing area, resulting in an exceptionally low detection limit of 100 fM. Futhermore, due to GaN material's inherent stability, this device exhibits long-term stability with sustained performance within a certain attenuation range even after 60 days. These stickers possess small, lightweight, and portable features that enable real-time cortisol detection within 5 minutes through direct sweat collection. The application of this technology holds great potential in the field of personal health management, facilitating users to conveniently monitor their mental and physical conditions.


Subject(s)
Aluminum Compounds , Biosensing Techniques , Gallium , Wearable Electronic Devices , Humans , Sweat/chemistry , Hydrocortisone/analysis , Electrons , Biosensing Techniques/methods
3.
Sci Rep ; 13(1): 20828, 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38012237

ABSTRACT

In contrast to traditional approaches to simulating fresh concrete, the model applied here allows issues such as liquid phase and the motion of sub-scale particles to be considered. The rheological behavior of fresh concrete materials was investigated, and the slump test and pumping process of fresh concrete were simulated by combining the smooth particle hydrodynamics coupled with discrete element method. Based on Bi-viscosity model and Bingham model, linear and nonlinear fitting of rheometer data and the derivation equations were educing. Bi-viscosity model and the Bingham model were compared in slump test. The results show that the Bi-viscosity model is more accurate in simulation, and the error percentage is less than 10%. The Bi-viscosity model was used to simulate and predict the results of slump experiment, and the influence of rheological parameters on the slump velocity and shape was obtained. The simulation analysis model of concrete single-cylinder pumping is established, and the experimental and simulation analysis models are compared. The results show that the SPH-DEM pumping pressure prediction is very close to the experimental results.

4.
J Pers Med ; 13(3)2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36983645

ABSTRACT

We evaluated the reading characteristics of normal-sighted young adults using C-Read to provide baseline healthy population values. We also investigated the relationship between the National Eye Institute's Visual Functioning Questionnaire (VFQ-25) score and reading ability, myopia, and hours of screen use, focusing on the extent to which these factors affect participants' visual function and, ultimately, their vision-related quality of life (QoL). Overall, 207 young, healthy participants (414 eyes) aged 18-35 years were tested for reading speed using C-Read connected to a smartphone-based application between December 2022 and January 2023. Each participant received a VFQ-25 questionnaire to evaluate vision-related QoL. Data on daily e-screen usage hours were collected. Among the participants, 91 (44.0%) were women; their mean (SD) age was 22.45 (4.01) years. The mean (SD) reading acuity (RA) was 0.242 (0.124), 0.249 (0.120), and 0.193 (0.104) logarithmic minimum angle of resolution (logMAR) for the right, left, and both eyes, respectively. The mean (SD) maximum reading speed (MRS) was 171.65 (46.27), 168.59 (45.68), and 185.16 (44.93) words per minute (wpm) with the right, left, and both eyes, respectively. The mean (SD) critical print size (CPS) was 0.412 (0.647), 0.371 (0.229), and 0.419 (1.05) logMAR per the right, left, and both eyes, respectively. The RA and CPS were significantly different between sexes (p = 0.002 and p = 0.001). MRS was significantly different between the education level (p = 0.005) and myopia level groups (p = 0.010); however, it was not clear whether this difference was confounded by age. The myopic power in diopters significantly affected RA (coefficient, -0.012; 95% CI, -0.018 to -0.006; p = 0.001); screen time significantly affected MRS (coefficient, 0.019; 95% CI, 0.57 to 6.33; p = 0.019). RA (coefficient, -21.41; 95% CI, -33.74 to -9.08; p = 0.001) and duration of screen use (coefficient, -0.86; 95% CI, -1.29 to -0.43; p < 0.001) independently had a significantly negative correlation with VFQ-25 scores. Our findings provide a baseline value for C-Read in normal-sighted young adults. Refractive status significantly affected RA, while screen time significantly affected MRS. Interventions aimed at enhancing RA may have the potential to maximize vision-related QoL and enable older adults with impaired vision to achieve greater outcomes. Future, larger-scale, C-Read experiments will help provide newer, more optimal methods for the early diagnosis of visual impairment.

5.
Eur J Med Chem ; 186: 111856, 2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31734021

ABSTRACT

Inhibiting the programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) pathway is an attractive strategy for tumor immunotherapy. Here, a novel series of indoline-containing compounds were developed, among which, A13 was identified as the most promising PD-1/PD-L1 pathway inhibitor. At the biochemical level, A13 demonstrated strong inhibition of the PD-1/PD-L1 interaction, with an IC50 of 132.8 nM. Notably, it exhibited outstanding immunoregulatory activity, and significantly elevated interferon-γ secretion in a Hep3B/OS-8/hPD-L1 and CD3 T cell co-culture model, without significant toxic effect. Therefore, A13 could be employed as a suitable lead compound for further design of non-peptide inhibitors targeting the PD-1/PD-L1 interaction. In addition, the preliminary structure-activity relationships of these new indoline compounds were investigated in this study, providing valuable information for future drug development.


Subject(s)
B7-H1 Antigen/antagonists & inhibitors , Drug Discovery , Indoles/pharmacology , Programmed Cell Death 1 Receptor/antagonists & inhibitors , B7-H1 Antigen/metabolism , Cells, Cultured , Dose-Response Relationship, Drug , Humans , Indoles/chemical synthesis , Indoles/chemistry , Jurkat Cells , Molecular Docking Simulation , Molecular Structure , Programmed Cell Death 1 Receptor/metabolism , Structure-Activity Relationship
6.
Jpn J Infect Dis ; 70(6): 678-681, 2017 Nov 22.
Article in English | MEDLINE | ID: mdl-28890512

ABSTRACT

Oxazolidinones constitute a novel class of antimicrobials as inhibitors of bacterial ribosomal protein synthesis. In this study, we identified 15 novel oxazolidinone analogs with potent antituberculosis activities. Compounds sy124 and sy125 showed the best activity in vitro (better than that of the linezolid) against various clinically relevant bacterial species, including most Gram-positive bacteria, Mycobacterium spp., and Helicobacter pylori. A cell-based assay indicated that these compounds have a strong ability to kill intracellular pathogens. Our results reveal that the newly identified compounds may be further developed as novel antimicrobial agents.


Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Linezolid/chemistry , Linezolid/pharmacology , Oxazolidinones/chemistry , Oxazolidinones/pharmacology , Bacteria/drug effects , Humans , Microbial Sensitivity Tests , Molecular Structure , Structure-Activity Relationship
7.
Eur J Med Chem ; 104: 115-26, 2015 Nov 02.
Article in English | MEDLINE | ID: mdl-26451770

ABSTRACT

The epidermal growth factor receptor (EGFR) T790M mutant is found in approximately 50% of clinically acquired resistance to gefitinib among patients with non-small cell lung cancer (NSCLC). Here, a series of novel aminopyrimidines bearing a hydrazone moiety were identified as potent and selective EGFR inhibitors. Compounds 14a, 15g, and 15i potently inhibited all EGFR mutants including EGFR T790M/L858R, EGFR T790M/delE746_A750, and EGFR T790M while they showed weak effects on the wild type (WT) EGFR. In addition, these compounds effectively suppressed proliferation of gefitinib-resistant H1975 (EGFR T790M/L858R) cells but were less potent against A549 (WT EGFR and k-Ras mutation) and HT-29 (non-special gene type) cells, showing a high safety index. Therefore, 14a, 15g, and 15i might be promising candidates to overcome drug resistance mediated by the EGFR T790M mutant.


Subject(s)
Antineoplastic Agents/pharmacology , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/genetics , Hydrazones/pharmacology , Mutant Proteins/antagonists & inhibitors , Protein Kinase Inhibitors/pharmacology , Pyrimidines/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , HT29 Cells , Humans , Hydrazones/chemistry , Molecular Structure , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Structure-Activity Relationship
8.
Eur J Med Chem ; 96: 173-86, 2015.
Article in English | MEDLINE | ID: mdl-25874341

ABSTRACT

Through a structure-based molecular hybridization approach, a series of novel benzothiazole derivatives bearing indole-based moiety were designed, synthesized and screened for in vitro antitumor activity against four cancer cell lines (HT29, H460, A549 and MDA-MB-231). Most of them showed moderate to excellent activity against all the tested cell lines. Among them, compounds 20a-w with substituted benzyl-1H-indole moiety showed better selectivity against HT29 cancer cell line than other compounds. Compound 20d exhibited excellent antitumor activity with IC50 values of 0.024, 0.29, 0.84 and 0.88 µM against HT29, H460, A549 and MDA-MB-231, respectively. Further mechanism studies indicated that the marked pharmacological activity of compound 20d might be ascribed to activation of procaspase-3 (apoptosis-inducing) and cell cycle arrest, which had emerged as a lead for further structural modifications. Furthermore, 3D-QSAR model (training set: q(2) = 0.850, r(2) = 0.987, test set: r(2) = 0.811) was built to provide a comprehensive guide for further structural modification and optimization.


Subject(s)
Antineoplastic Agents/pharmacology , Benzothiazoles/pharmacology , Drug Design , Indoles/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Benzothiazoles/chemical synthesis , Benzothiazoles/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Indoles/chemistry , Models, Molecular , Molecular Structure , Quantitative Structure-Activity Relationship
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