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1.
Small ; : e2403079, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829022

RESUMO

Phosphate-based electrolyte propels the advanced battery system with high safety. Unfortunately, restricted by poor electrochemical stability, it is difficult to be compatible with advanced lithium metal anodes and Ni-rich cathodes. To alleviate these issues, the study has developed a phosphate-based localized high-concentration electrolyte with a nitrate-driven solvation structure, and the nitrate-derived N-rich inorganic interface shows excellent performance in stabilizing the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode interface and modulating the lithium deposition morphology on the anode. The results show that the Li|| NCM811 cell has exceptional long-cycle stability of >80% capacity retention after 800 cycles at 4.3 V, 1 C. A more prominent capacity retention rate of 93.3% after 200 cycles can be reached with the high voltage of 4.5 V. While being compatible with the phosphate-based electrolyte with good flame retardancy and the good electrochemical stability of Ni-rich lithium metal battery (LMBs) systems, the present work expands the construction of anion-rich solvation structures, which is expected to promote the development of the high-performance LMBs with safety.

2.
ISA Trans ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38834424

RESUMO

This study investigates pigeon-like flexible flapping wings, which are known for their low energy consumption, high flexibility, and lightweight design. However, such flexible flapping wing systems are prone to deformation and vibration during flight, leading to performance degradation. It is thus necessary to design a control method to effectively manage the vibration of flexible wings. This paper proposes an improved rigid finite element method (IRFE) to develop a dynamic visualization model of flexible flapping wings. Subsequently, an adaptive vibration controller was designed based on non-singular terminal sliding mode (NTSM) control and fuzzy neural network (FNN) in order to effectively solve the problems of system uncertainty and actuator failure. With the proposed control, stability of the closed loop system is achieved in the context of Lyapunov's stability theory. At last, a joint simulation using MapleSim and MATLAB/Simulink was conducted to verify the effectiveness and robustness of the proposed controller in terms of trajectory tracking and vibration suppression.The obtained results have demonstrated great practical value of the proposed method in both military (low-altitude reconnaissance, urban operations, and accurate delivery, etc.) and civil (field research, monitoring, and relief for disasters, etc.) applications.

3.
Small ; : e2402123, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804876

RESUMO

The localized high-concentration electrolyte (LHCE) propels the advanced high-voltage battery system. Sulfone-based LHCE is a transformative direction compatible with high energy density and high safety. In this work, the application of lithium bis(trifluoromethanesulphonyl)imide and lithium bis(fluorosulfonyl)imide (LiFSI) in the LHCE system constructed from sulfolane and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE) is investigated. The addition of diluent causes an increase of contact ion pairs and ionic aggregates in the solvation cluster and an acceptable quantity of free solvent molecules. A small amount of LiFSI as an additive can synergistically decompose with TTE on the cathode and participate in the construction of both electrode interfaces. The designed electrolyte helps the Ni-rich system to cycle firmly at a high voltage of 4.5 V. Even with high mass load and lean electrolyte, it can keep a reversible specific capacity of 91.5% after 50 cycles. The constructed sulfone-based electrolyte system exhibits excellent thermal stability far beyond the commercial electrolytes. Further exploration of in-situ gelation has led to a quick conversion of the designed liquid electrolyte to the gel state, accompanied by preserved stability, which provides a direction for the synergistic development of LHCE with gel electrolytes.

4.
Small ; : e2401241, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38660829

RESUMO

It is challenging to sufficiently regulate endogenous neuronal reactive oxygen species (ROS) production, reduce neuronal apoptosis, and reconstruct neural networks under spinal cord injury conditions. Here, hydrogel surface grafting and microsol electrospinning are used to construct a composite biomimetic scaffold with "external-endogenous" dual regulation of ROS. The outer hydrogel enhances local autophagy through responsive degradation and rapid release of rapamycin (≈80% within a week), neutralizing extracellular ROS and inhibiting endogenous ROS production, further reducing neuronal apoptosis. The inner directional fibers continuously supply brain-derived neurotrophic factors to guide axonal growth. The results of in vitro co-culturing show that the dual regulation of oxidative metabolism by the composite scaffold approximately doubles the neuronal autophagy level, reduces 60% of the apoptosis induced by oxidative stress, and increases the differentiation of neural stem cells into neuron-like cells by ≈2.5 times. The in vivo results show that the composite fibers reduce the ROS levels by ≈80% and decrease the formation of scar tissue. RNA sequencing results show that composite scaffolds upregulate autophagy-associated proteins, antioxidase genes, and axonal growth proteins. The developed composite biomimetic scaffold represents a therapeutic strategy to achieve neurofunctional recovery through programmed and accurate bidirectional regulation of the ROS cascade response.

5.
ACS Appl Mater Interfaces ; 16(15): 19730-19741, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591140

RESUMO

Metal-organic framework materials can be converted into carbon-based nanoporous materials by pyrolysis, which have a wide range of applications in energy storage. Here, we design special interface engineering to combine the carbon skeleton and nitrogen-doped carbon nanotubes (CNTs) with the transition metal compounds (TMCs) well, which mitigates the bulk effect of the TMCs and improves the conductivity of the electrodes. Zeolitic imidazolate framework-67 is used as a precursor to form a carbon skeleton and a large number of nitrogen-doped CNTs by pyrolysis followed by the in situ formation of Co3O4 and CoS2, and finally, Co3O4@CNTs and CoS2@CNTs are synthesized. The obtained anode electrodes exhibit a long cycle life and high-rate properties. In lithium-ion batteries (LIBs), Co3O4@CNTs have a high capacity of 581 mAh g-1 at a high current of 5 A g-1, and their reversible capacity is still 1037.6 mAh g-1 after 200 cycles at 1 A g-1. In sodium-ion batteries (SIBs), CoS2@CNTs have a capacity of 859.9 mAh g-1 at 0.1 A g-1 and can be retained at 801.2 mAh g-1 after 50 cycles. The unique interface engineering and excellent electrochemical properties make them ideal anode materials for high-rate, long-life LIBs and SIBs.

6.
J Chem Phys ; 160(11)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38501473

RESUMO

We establish a theoretical model to analyze the photoassociative spectroscopy of 85Rb 133Cs molecules in the (3)3Σ+ state. The vibrational energy, spin-spin coupling constant, and hyperfine interaction constant of the (3)3Σ+ state are determined based on nine observed vibrational levels. Consequently, the Rydberg-Klein-Rees potential energy curve of the (3)3Σ+ state is obtained and compared with the ab initial potential energy curve. Our model can be adopted to analyze the photoassociative spectroscopy of other heteronuclear alkali-metal diatomic molecules in the (3)3Σ+ state.

7.
Bioact Mater ; 37: 132-152, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38549774

RESUMO

Sustained and intense inflammation is the pathological basis for intervertebral disc degeneration (IVDD). Effective antagonism or reduction of local inflammatory factors may help regulate the IVDD microenvironment and reshape the extracellular matrix of the disc. This study reports an immunomodulatory hydrogel microsphere system combining cell membrane-coated mimic technology and surface chemical modification methods by grafting neutrophil membrane-coated polylactic-glycolic acid copolymer nanoparticles loaded with transforming growth factor-beta 1 (TGF-ß1) (T-NNPs) onto the surface of methacrylic acid gelatin anhydride microspheres (GM) via amide bonds. The nanoparticle-microsphere complex (GM@T-NNPs) sustained the long-term release of T-NNPs with excellent cell-like functions, effectively bound to pro-inflammatory cytokines, and improved the release kinetics of TGF-ß1, maintaining a 36 day-acting release. GM@T-NNPs significantly inhibited lipopolysaccharide-induced inflammation in nucleus pulposus cells in vitro, downregulated the expression of inflammatory factors and matrix metalloproteinase, and upregulated the expression of collagen-II and aggrecan. GM@T-NNPs effectively restored intervertebral disc height and significantly improved the structure and biomechanical function of the nucleus pulposus in a rat IVDD model. The integration of biomimetic technology and nano-drug delivery systems expands the application of biomimetic cell membrane-coated materials and provides a new treatment strategy for IVDD.

8.
Colloids Surf B Biointerfaces ; 238: 113870, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38555763

RESUMO

Antibiotic resistance has become an urgent threat to health care in recent years. The use of drug delivery systems provides advantages over conventional administration of antibiotics and can slow the development of antibiotic resistance. In the current study, we developed a toxin-triggered liposomal antibiotic delivery system, in which the drug release is enabled by the leukotoxin (LtxA) produced by the Gram-negative pathogen, Aggregatibacter actinomycetemcomitans. LtxA has previously been shown to mediate membrane disruption by promoting a lipid phase change in nonlamellar lipids, such as 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-methyl (N-methyl-DOPE). In addition, LtxA has been observed to bind strongly and nearly irreversibly to membranes containing large amounts of cholesterol. Here, we designed a liposomal delivery system composed of N-methyl-DOPE and cholesterol to take advantage of these interactions. Specifically, we hypothesized that liposomes composed of N-methyl-DOPE and cholesterol, encapsulating antibiotics, would be sensitive to LtxA, enabling controlled antibiotic release. We observed that liposomes composed of N-methyl-DOPE were sensitive to the presence of low concentrations of LtxA, and cholesterol increased the extent and kinetics of content release. The liposomes were stable under various storage conditions for at least 7 days. Finally, we showed that antibiotic release occurs selectively in the presence of an LtxA-producing strain of A. actinomycetemcomitans but not in the presence of a non-LtxA-expressing strain. Together, these results demonstrate that the designed liposomal vehicle enables toxin-triggered delivery of antibiotics to LtxA-producing strains of A. actinomycetemcomitans.


Assuntos
Aggregatibacter actinomycetemcomitans , Antibacterianos , Lipossomos , Lipossomos/química , Antibacterianos/farmacologia , Antibacterianos/química , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Liberação Controlada de Fármacos , Colesterol/química , Colesterol/metabolismo , Testes de Sensibilidade Microbiana , Exotoxinas/metabolismo , Exotoxinas/química , Fosfatidiletanolaminas/química , Sistemas de Liberação de Medicamentos
9.
Nat Methods ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38366243

RESUMO

Analysis of single-cell datasets generated from diverse organisms offers unprecedented opportunities to unravel fundamental evolutionary processes of conservation and diversification of cell types. However, interspecies genomic differences limit the joint analysis of cross-species datasets to homologous genes. Here we present SATURN, a deep learning method for learning universal cell embeddings that encodes genes' biological properties using protein language models. By coupling protein embeddings from language models with RNA expression, SATURN integrates datasets profiled from different species regardless of their genomic similarity. SATURN can detect functionally related genes coexpressed across species, redefining differential expression for cross-species analysis. Applying SATURN to three species whole-organism atlases and frog and zebrafish embryogenesis datasets, we show that SATURN can effectively transfer annotations across species, even when they are evolutionarily remote. We also demonstrate that SATURN can be used to find potentially divergent gene functions between glaucoma-associated genes in humans and four other species.

10.
Med Res Rev ; 44(4): 1662-1682, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38299968

RESUMO

Prostate, bladder, and kidney cancers are the most common malignancies of the urinary system. Chemotherapeutic drugs are generally used as adjuvant treatment in the middle, late, or recurrence stages after surgery for urologic cancers. However, traditional chemotherapy is plagued by problems such as poor efficacy, severe side effects, and complications. Copper-containing nanomedicines are promising novel cancer treatment modalities that can potentially overcome these disadvantages. Copper homeostasis and cuproptosis play crucial roles in the development, adaptability, and therapeutic sensitivity of urological malignancies. Cuproptosis refers to the direct binding of copper ions to lipoylated components of the tricarboxylic acid cycle, leading to protein oligomerization, loss of iron-sulfur proteins, proteotoxic stress, and cell death. This review focuses on copper homeostasis and cuproptosis as well as recent findings on copper and cuproptosis in urological malignancies. Furthermore, we highlight the potential therapeutic applications of copper- and cuproptosis-targeted therapies to better understand cuproptosis-based drugs for the treatment of urological tumors in the future.


Assuntos
Cobre , Neoplasias Urológicas , Humanos , Cobre/metabolismo , Neoplasias Urológicas/metabolismo , Neoplasias Urológicas/tratamento farmacológico , Animais , Homeostase
11.
Adv Healthc Mater ; 13(11): e2303851, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38226706

RESUMO

Targeting macrophages can facilitate the site-specific repair of critical bone defects. Herein, a composite hydrogel, gelatin-Bletilla striata polysaccharide-mesoporous bioactive glass hydrogel (GBMgel), is constructed via the self-assembly of mesoporous bioactive glass on polysaccharide structures, through the Schiff base reaction. GBMgel can efficiently capture macrophages and drive the recruitment of seed stem cells and vascular budding required for regeneration in the early stages of bone injury, and the observed sustained release of inorganic silicon ions further enhances bone matrix deposition, mineralization, and vascular maturation. Moreover, the use of macrophage-depleted rat calvarial defect models further confirms that GBMgel, with ligand-selective macrophage targeting, increases the bone regeneration area and the proportion of mature bone. Mechanistic studies reveal that GBMgel upregulates the TLR4/NF-κB and MAPK macrophage pathways in the early stages and the JAK/STAT3 pathway in the later stages; thus initiating macrophage polarization at different time points. In conclusion, this study is based on the endogenous self-healing properties of bone macrophages, which enhances stem cell homing, and provides a research and theoretical basis upon which bone tissue can be reshaped and regenerated using the body's immune power, providing a new strategy for the treatment of critical bone defects.


Assuntos
Regeneração Óssea , Hidrogéis , Macrófagos , Animais , Regeneração Óssea/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Ratos , Ratos Sprague-Dawley , Camundongos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Células RAW 264.7 , Ligantes , Masculino , Gelatina/química , Crânio/efeitos dos fármacos , Crânio/patologia , Crânio/lesões , Polissacarídeos/química , Polissacarídeos/farmacologia
12.
IEEE Trans Pattern Anal Mach Intell ; 46(5): 3972-3980, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38224500

RESUMO

Backpropagation (BP) is widely used for calculating gradients in deep neural networks (DNNs). Applied often along with stochastic gradient descent (SGD) or its variants, BP is considered as a de-facto choice in a variety of machine learning tasks including DNN training and adversarial attack/defense. Recently, a linear variant of BP named LinBP was introduced for generating more transferable adversarial examples for performing black-box attacks, by (Guo et al. 2020). Although it has been shown empirically effective in black-box attacks, theoretical studies and convergence analyses of such a method is lacking. This paper serves as a complement and somewhat an extension to Guo et al. (2020) paper, by providing theoretical analyses on LinBP in neural-network-involved learning tasks, including adversarial attack and model training. We demonstrate that, somewhat surprisingly, LinBP can lead to faster convergence in these tasks in the same hyper-parameter settings, compared to BP. We confirm our theoretical results with extensive experiments.

14.
J Control Release ; 365: 1124-1138, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38123070

RESUMO

Following an ocular chemical injury, the release of neutrophil extracellular traps (NETs) triggers an innate immune cascade fibrotic effect involving macrophages (Mø), which limits corneal repair. However, the interplay and mechanisms between NETs and macrophages, as well as the coordination between the innate immunity and corneal repair, remain challenging issues. Using a co-culture system, we report that chemical stimulation exacerbates the accumulation of reactive oxygen species (ROS) within the polymorphonuclear neutrophils, leading to NET formation and the activation of M2 macrophages, ultimately inducing pathological fibrosis of the ocular surface through the IL-10/STAT3/TGF-ß1/Smad2 axis. Inspired by the locally formed acidic microenvironment mediated by innate acute inflammatory stimulation, we further integrate sericin with oxidized chitosan nanoparticles loaded with black phosphorus quantum dots (BPQDs) using Schiff base chemistry to construct a functional pH-responsive hydrogel. Following corneal injury, the hydrogel selectively releases BPQDs in response to the acidic environment, inhibiting the innate immune cascade fibrosis triggered by the PMN-ROS-NETs. Thus, corneal pathological fibrosis is alleviated and reshaping of the ocular surface takes place. These results represent a refinement of the mechanism of inherent immune effector cell interactions, and provide new research ideas for the construction of nano biomaterials that regulate pathological fibrosis.


Assuntos
Hidrogéis , Neutrófilos , Humanos , Espécies Reativas de Oxigênio , Hidrogéis/farmacologia , Imunidade Inata , Fibrose
15.
Int J Mol Sci ; 24(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38069311

RESUMO

Although recent research progress on the abundant C-to-U RNA editing events in plant chloroplasts and mitochondria has uncovered many recognition factors and their molecular mechanisms, the intrinsic regulation of RNA editing within plants remains largely unknown. This study aimed to establish a regulatory relationship in Arabidopsis between the plant hormone auxin and chloroplast RNA editing. We first analyzed auxin response elements (AuxREs) present within promoters of chloroplast editing factors reported to date. We found that each has more than one AuxRE, suggesting a potential regulatory role of auxin in their expression. Further investigation unveiled that the depletion of auxin synthesis gene YUC2 reduces the expression of several editing factors. However, in yuc2 mutants, only the expression of CRR4, DYW1, ISE2, and ECD1 editing factors and the editing efficiency of their corresponding editing sites, ndhD-2 and rps14-149, were simultaneously suppressed. In addition, exogenous IAA and the overexpression of YUC2 enhanced the expression of these editing factors and the editing efficiency at the ndhD-2 and rps14-149 sites. These results suggested a direct effect of auxin upon the editing of the ndhD-2 and rps14-149 sites through the modulation of the expression of the editing factors. We further demonstrated that ARF1, a downstream transcription factor in the auxin-signaling pathway, could directly bind to and inactivate the promoters of CRR4, DYW1, and ISE2 in a dual-luciferase reporter system, thereby inhibiting their expression. Moreover, the overexpression of ARF1 in Arabidopsis significantly reduced the expression of the three editing factors and the editing efficiency at the ndhD-2 and rps14-149 sites. These data suggest that YUC2-mediated auxin biosynthesis governs the RNA-editing process through the ARF1-dependent signal transduction pathway.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Transporte/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Proteínas Ribossômicas/metabolismo , Edição de RNA , RNA de Cloroplastos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
bioRxiv ; 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37808632

RESUMO

Antibiotic resistance has become an urgent threat to health care in recent years. The use of drug delivery systems provides advantages over conventional administration of antibiotics and can slow the development of antibiotic resistance. In the current study, we developed a toxin-triggered liposomal antibiotic delivery system, in which the drug release is enabled by the leukotoxin (LtxA) produced by the Gram-negative pathogen, Aggregatibacter actinomycetemcomitans. LtxA has previously been shown to mediate membrane disruption by promoting a lipid phase change in nonlamellar lipids, such as 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-methyl (N-methyl-DOPE). In addition, LtxA has been observed to bind strongly and nearly irreversibly to membranes containing large amounts of cholesterol. Here, we designed a liposomal delivery system composed of N-methyl-DOPE and cholesterol to take advantage of these interactions. Specifically, we hypothesized that liposomes composed of N-methyl-DOPE and cholesterol, encapsulating antibiotics, would be sensitive to LtxA, enabling controlled antibiotic release. We observed that liposomes composed of N-methyl-DOPE were sensitive to the presence of low concentrations of LtxA, and cholesterol increased the extent and kinetics of content release. The liposomes were stable under various storage conditions for at least 7 days. Finally, we showed that antibiotic release occurs selectively in the presence of an LtxA-producing strain of A. actinomycetemcomitans but not in the presence of a non-LtxA-expressing strain. Together, these results demonstrate that the designed liposomal vehicle enables toxin-triggered delivery of antibiotics to LtxA-producing strains of A. actinomycetemcomitans.

17.
Regen Med ; 18(10): 795-807, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37702008

RESUMO

Research has shown that the therapeutic effect of mesenchymal stem cells (MSCs) is partially due to its secreted factors as opposed to the implantation of the cells into the treated tissue or tissue replacement. MSC secretome, especially in the form of conditioned medium (MSC-CM) is now being explored as an alternative to MSCs transplantation. Despite the observed benefits of MSC-CM, only a few clinical trials have evaluated it and other secretome components in the treatment of eye diseases. This review provides insight into the potential therapeutic use of MSC-CM in eye conditions, such as corneal diseases, dry eye, glaucoma, retinal diseases and uveitis. We discuss the current evidence, some limitations, and the progress that remains to be achieved before clinical translation becomes possible.


Assuntos
Células-Tronco Mesenquimais , Secretoma , Meios de Cultivo Condicionados/farmacologia
18.
BMC Surg ; 23(1): 253, 2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37635216

RESUMO

OBJECTIVE: We compared the outcome of radical prostatectomy (RP) with seed brachytherapy (BT) in clinically localized prostate cancer (LPCa) using two different biochemical recurrence (BCR) definitions. METHODS: Clinical data of 1117 patients with non-metastatic prostate cancer (PCa) treated with either RP or BT as the basis of the multimodal therapy from a single tertiary hospital between 2007 and 2021 were retrospectively analyzed. 843 LPCa patients (RP = 737, BT = 106) with at least one prostate-specific antigen (PSA) test after treatment were finally included. The BCR survival was evaluated by direct comparison and one-to-one propensity score matching (PSM) analysis using surgical definition (PSA ≥ 0.2ng/ml) for RP and surgical/Phoenix definition (PSA nadir + 2ng/ml ) for BT. The propensity score (PS) was calculated by multivariable logistic regression based on the clinicopathological parameters. RESULTS: Median follow-up was 43 months for RP patients and 45 months for BT patients. Kaplan-Meier analysis did not show any statistically significant differences in terms of BCR-free survival (BFS) between the two groups when using Phoenix definition for BT (P > 0.05). Similar results were obtained in all D'Amico risk groups when stratified analyses were conducted. However, RP achieved improved BFS compared to BT in the whole cohort and all risk groups with the surgical definition for BT(P < 0.05). After adjusting PS, 192 patients were divided into RP and BT groups (96 each). RP presented a better BFS than BT when using the surgical definition (P < 0.001), but no significant difference was found when using the Phoenix definition (P = 0.609). CONCLUSION: Inconsistent BCR-free survival outcomes were acquired using two different BCR definitions for BT patients. RP provided comparable BFS with BT using the Phoenix definition but better BFS using the surgical definition, regardless of whether the PSM was performed. Our findings indicated that an exact BCR definition was critical for prognostic assessment. The corresponding results will assist physicians in pretreatment consultation and treatment selection.


Assuntos
Braquiterapia , Neoplasias da Próstata , Masculino , Humanos , Antígeno Prostático Específico , Estudos Retrospectivos , Prostatectomia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia
19.
Phys Chem Chem Phys ; 25(33): 21908-21915, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37581209

RESUMO

Vanadium dioxide (VO2) exhibits the most abrupt metal-to-insulator transition (MIT) property near room temperature among the representative 3d-orbital correlated oxides, and its structural variation during the MIT usually results in poor mechanical properties as bulk pellets. Moreover, compositing with highly resistive oxides has been reported to improve the mechanical strength of bulk VO2 since the generation and propagation of microcracks is suppressed upon thermocycling across the MIT; further, their respective impacts on electrical transportation are yet unclear. Herein, we demonstrate the role of these highly resistive oxide composites (e.g., HfO2, CoO and Al2O3) in reducing charge leakage along the microcracks within the insulating phase of VO2, leading to more abrupt MIT properties from the perspective of electrical transportation. This enables the possibility of simultaneously regulating the critical temperature and abrupt MIT transition, as well as the mechanical properties of the VO2 bulk pellets via compositing with oxides with different melting points using spark plasma-assisted reactive sintering (SPARS).

20.
Arch Esp Urol ; 76(4): 264-269, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37455525

RESUMO

OBJECTIVE: We aimed to investigate the predictive value of imaging features derived from magnetic resonance imaging (MRI) and develop a radiomics model predicting the biochemical recurrence-free survival (BFS) in prostate cancer (PCa) patients treated with seed brachytherapy (seed-BT). METHODS: The data of 272 patients with PCa treated with seed-BT at Peking University Third Hospital from 2007 to 2019 was retrospectively investigated. Based on the eligibility criteria, 83 patients were finally included in our study. The cohort was divided into two groups in a ratio of 8:2 (training set: n = 67, test set: n = 16). The Cox survival model combined with the least absolute shrinkage and selection operator (LASSO) algorithm was applied to select the radiomics features from T2WI of pretreatment MRI. A radiomics model with selected features was established to predict the BFS. RESULTS: Nineteen patients experienced biochemical recurrence (BCR) during a median follow-up period of 46 months. Three features with non-zero coefficients were selected from 1598 features and used to construct a radiomics model for BCR prediction. The model accurately predicted the BCR in both the training and test groups, for which the concordance index (C-index) were 0.83 and 0.78, respectively. Receiver operating characteristic (ROC) analysis of the test set was conducted to assess the prediction accuracy. The model achieved a high area under the operator curve (AUC) performance for BCR prediction in the test cohort. CONCLUSIONS: Our study revealed the considerable potential of a radiomics model based on MRI-derived imaging features in BCR prediction of PCa patients after seed-BT. Radiomics provides a new perspective to clinicians assessing the outcome of radiotherapy, facilitating accurate prognostic evaluation and preoperative consultation for PCa patients followed by seed-BT.


Assuntos
Braquiterapia , Neoplasias da Próstata , Masculino , Humanos , Estudos Retrospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Imageamento por Ressonância Magnética , Sementes
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