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1.
Artigo em Inglês | MEDLINE | ID: mdl-39316669

RESUMO

Ni-rich single-crystalline layered cathodes have garnered significant attention due to their high energy density and thermal stability. However, they experience severe capacity degradation caused by lattice strain and interfacial side reactions during practical applications. In this study, an effective yttrium modification method is employed to stabilize the structure of Ni-rich single-crystalline LiNi0.83Mn0.05Co0.12O2 (SC-NMC83) to solve these issues. This innovative approach successfully immobilizes oxygen within the material, preventing crack formation while simultaneously broadening the diffusion path of Li+. The yttrium-modified sample (SC-NMC83-Y) exhibits a superior capacity retention compared to the SC-NMC83 sample, with values of 90% and 76.1% after 100 cycles, respectively. This work demonstrates the promising potential of a doping strategy for Ni-rich single-crystalline cathodes and paves a pathway for its practical implementation, such as all-solid-state batteries.

2.
NPJ Breast Cancer ; 10(1): 72, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112498

RESUMO

Breast cancer diagnosis and treatment have been revolutionized by multiparametric Magnetic Resonance Imaging (mpMRI), encompassing T2-weighted imaging (T2WI), Diffusion-weighted imaging (DWI), and Dynamic Contrast-Enhanced MRI (DCE-MRI). We conducted a retrospective analysis of mpMRI data from 194 breast cancer patients (September 2019 to October 2023). Using 'pyradiomics' for radiomics feature extraction and MOVICS for unsupervised clustering. Interestingly, we identified two distinct patient clusters associated with significant differences in molecular subtypes, particularly in Luminal A subtype distribution (p = 0.03), estrogen receptor (ER) (p = 0.01), progesterone receptor (PR) (p = 0.04), mean tumor size (p < 0.01), lymph node metastasis (LNM) (p = 0.01), and edema (p < 0.01). Our study emphasizes mpMRI's potential in breast cancer by using radiomics-based cluster analysis to categorize tumors, uncovering heterogeneity, and aiding in personalized treatment strategies.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37878046

RESUMO

Pyroptosis-mediated neuron death plays a crucial role in neurodegenerative diseases, such as Alzheimer's disease (AD). However, the effect of 1,7-diphenyl-4-hepten-3-one (C1), a natural diarylheptanoid, on AD is unclear. Herein, we investigated the therapeutic effect of C1 on APP/PS1 mice and ß-amyloid (Aß)-induced HT22 cells. Our findings showed that C1 attenuated cognitive impairment and mitigated pathological damage in APP/PS1 mice. Furthermore, we found that C1 prevented oxidative stress damage and decreased the levels of pyroptosis-related proteins. In vitro experiments showed that C1 can improve the proliferation of Aß-induced HT22 cells and decrease the levels of pyroptosis-related proteins in them. When Nrf2 was silenced, the positive effects of C1 in inhibiting pyroptosis were inhibited. Particularly, the production of pyroptosis-associated proteins, including NLRP3, GSDMD, and caspase-1, and the secretion of pro-inflammatory molecules, including IL-1 and IL-18, were increased. Altogether, these findings indicate that C1 can mitigate AD-like pathology via the inhibition of pyroptosis by activating the Nrf2 pathway. We believe that this study can provide alternative strategies for the prevention and treatment of AD.

4.
Technol Health Care ; 31(5): 1799-1808, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36970925

RESUMO

BACKGROUND: Gastric cancer (GC) is the fifth most common cancer worldwide and the third leading cause of cancer death. Due to the low rate of early diagnosis, most patients are already in the advanced stage and lose the chance of radical surgery. OBJECTIVE: To investigate the clinical value of computed tomography (CT) dual-energy imaging in preoperative evaluation of pathological types of gastric cancer patients. METHODS: 121 patients with gastric cancer were selected. Dual-energy CT imaging was performed on the patients. The CT values of virtual noncontrast (VNC) images and iodine concentration of the lesion were measured, and the standardized iodine concentration ratio was calculated. The iodine concentration, iodine concentration ratio and CT values of VNC images of different pathological types were analyzed and compared. RESULTS: The iodine concentration and iodine concentration ratio of gastric mucinous carcinoma patients in venous phase and parenchymal phase were lower than those of gastric non-mucinous carcinoma patients, and the differences were statistically significant (P< 0.05). The iodine concentration and iodine concentration ratio of patients with mucinous adenocarcinoma in venous phase and parenchymal phase were lower than those of patients with choriocarcinoma, and the differences were statistically significant (P< 0.05). The iodine concentration and iodine concentration ratio of middle and high differentiated adenocarcinoma patients in venous phase and parenchymal phase were lower than those of low differentiated adenocarcinoma patients, and the differences were statistically significant (P< 0.05). However, there was no significant difference in CT values of VNC images among venous, arterial, and parenchymal phases in all pathological types of gastric cancer patients (P> 0.05). CONCLUSION: Dual-energy CT imaging plays an important role in the preoperative evaluation of patients with gastric cancer. The pathological types of gastric cancer are different, and the iodine concentration will change accordingly. Dual-energy CT imaging can effectively evaluate the pathological types of gastric cancer and has high clinical application value.


Assuntos
Adenocarcinoma , Iodo , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X/métodos , Adenocarcinoma/patologia , Estudos Retrospectivos
5.
Foods ; 11(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35804746

RESUMO

Momordica charantia L. (Cucurbitaceae) is rich in saponins, which have multiple biological effects. In this study, the total saponins of M. charantia were extracted by high hydrostatic pressure (HHP) technology. The optimal extraction process was determined (ethanol concentration 68%, pressure-holding time 8 min, ratio of material to solvent 1:35 and pressure 510 MPa), and the extraction amount of saponins reached 127.890 mg/g. On this basis, an ionic liquid-based aqueous biphasic system was constructed to purify the total saponins. Under the optimized conditions, the purity of M. charantia saponins was 76.06%. Liquid chromatography-mass spectrometry (LC/MS) was used to characterize the saponins in the purified extract of M. charantia. It was found that there were four kinds of saponins in the extract of M. charantia: kuguaglycoside A, momordicoside L, kuguacin B and kuguacin J, providing a basis for the study of the biological activity of saponins.

6.
Chemphyschem ; 23(15): e202200248, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35522010

RESUMO

Rechargeable Mg batteries (RMBs) are advantageous large-scale energy-storage devices because of the high abundance and high safety, but exploring high-performance cathodes remains the largest difficulty for their development. Compared with oxides and sulfides, selenides show better Mg-storage performance because the weaker interaction with the Mg2+ cation favors fast kinetics. Herein, nanorod-like FeSe2 was synthesized and investigated as a cathode for RMBs. Compared with microspheres and microparticles, nanorods exhibit higher capacity and better rate capability with a smaller particle size. The FeSe2 nanorods show a high capacity of 191 mAh g-1 at 50 mA g-1 and a good rate performance of 39 mAh g-1 at 1000 mA g-1 . Ex situ characterizations demonstrate the Mg2+ intercalation mechanism for FeSe2 , and a slight conversion reaction occurs on the surface of the particles. The capacity fading is mainly because of the dissolution of Fe2+ , which is caused by the reaction between Fe2+ and Cl- of the electrolyte during the charge process on the surface of the particles. The surface of FeSe2 is mainly selenium after long cycling, which may also dissolve in the electrolyte during cycling. The present work develops a new type of Mg2+ intercalation cathode for RMBs. More importantly, the fading mechanism revealed herein has considered the specificity of Mg battery electrolyte and would assist a better understanding of selenide cathodes for RMBs.

7.
Chemphyschem ; 22(14): 1455-1460, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34117706

RESUMO

Inorganic cathodes of rechargeable Mg batteries suffer from limited selections, while organic materials provide more options. Herein, three conjugated dianhydrides, pyromellitic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride and 3,4,9,10-perylenetetracarboxylic dianhydride are comparatively investigated to elucidate the effects of conjugated structure on the Mg2+ storage performances. It is observed that the reversible Mg2+ storage capacity is more dependent on the conjugated structure than carbonyl numbers. Ex-situ mechanism study illustrates that the extended conjugated structure delocalizes the electron density, hence enhancing carbonyl enolization and increasing the Mg2+ storage capacity. Furthermore, the largely conjugated structure buffers the charge density change during repeated magnesiation/demagnesiation resulting in better cyclability. Prominently, 3,4,9,10-perylenetetracarboxylic dianhydride shows a high Mg2+ storage capacity (160 mAh g-1 ) and a good cycling stability (80 % capacity retention after 100 cycles) with the largest conjugated structure. This work provides a low-cost cathode for rechargeable Mg batteries that can be utilized for designing high-performance organic Mg battery cathodes.

8.
Foods ; 9(4)2020 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-32290555

RESUMO

Physicochemical properties and volatiles of kiwifruit pulp beverage treated with high hydrostatic pressure (HHP, 400-600 MPa/5-15 min) were investigated during 40-day refrigerated storage. Compared with heat treatment (HT), HHP ranged from 400-500 MPa was superior in retaining vitamin C, fresh-like color and volatiles, while soluble solids content and pH were not affected significantly. Furthermore, HHP improved brightness and inhibited browning of kiwifruit pulp beverage. Samples treated at 400 MPa for 15 min showed significantly higher vitamin C content and lower ∆E values over 40 days than heat-treated kiwifruit pulp beverage. The total content of alcohols, esters, acids, and ketones gradually increased, whereas the total aldehydes content decreased during storage. Interestingly, HHP treatment at 500 MPa for 15 min mostly retained important characteristic volatiles including hexanal and (E)-2-hexenal, indicating this treatment was more conducive to preserve the original fruity, fresh, grassy and green notes of kiwifruit pulp beverage than HT.

9.
Med Phys ; 46(12): e823-e834, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31811792

RESUMO

PURPOSE: Metal artifact is a quite common problem in diagnostic dental computed tomography (CT) images. Due to the high attenuation of heavy materials such as metal, severe global artifacts can occur in reconstructions. Typical metal artifact reduction (MAR) techniques segment out the metal regions and estimate the corrupted projection data by various interpolation methods. However, interpolations are not accurate and introduce new artifacts or even deform the teeth in the reconstructed image. This work presents a new strategy to take advantage of the power of deep learning for metal artifact reduction. METHOD: The analysis first uses coarse reconstructions from simulated locally interpolated data affected by metal fillings as a starting point. A deep learning network is then trained using the simulated data and applied to practical data. Thus, an easily implemented three-step MAR method is formed: Firstly, use the acquired projection data to create a preliminary image reconstruction with linearly interpolated data for the metal-related projections. Secondly, a deep learning network is used to remove the artifacts from the linear interpolation and recover the nonmetal region information. Thirdly, the method adds the ROI reconstruction of the metal regions. The structures behind the shading artifacts in the direct filtered back-projection (FBP) reconstruction can be partially recovered by interpolation-based MAR (I-MAR) with the network further correcting for interpolation errors. The key to this method is that the linear interpolation reconstruction errors can be easily simulated to train a network and the effectiveness of the network can be easily generalized to I-MAR results in real situations. RESULTS: We trained a network with a simulation dataset and validated the network against a separate simulation dataset. Then, the network was tested using simulation data that did not overlap with the training/validation datasets and real patient datasets. Both tests gave encouraging results with accurate tooth structure recovery and few artifacts. The relative root mean square error and structure similarity index method indexes were significantly improved in the tests. The method was also evaluated by two experienced dentists who gave positive evaluations. CONCLUSIONS: This work presents a strategy to build a transferable learning from simulations to practical systems for metal artifact reduction using a supervised deep learning method. The system transforms the MAR analyses to an interpolation-artifact reduction problem to recover structural details from the coarse interpolation reconstruction. In this way, training data from simulations with ground truth labels can easily model the similar features in real data with I-MAR as the bridge. The network can seamlessly optimize both simulations and real data. The whole method is easily implemented with little computational cost. Test results demonstrated that this is an effective MAR method applicable to practical dental CT systems.


Assuntos
Artefatos , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Metais , Odontologia , Aprendizado de Máquina Supervisionado
10.
PeerJ ; 6: e4550, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29607262

RESUMO

Ornithogalum mosaic virus (OrMV) has a wide host range and affects the production of a variety of ornamentals. In this study, the coat protein (CP) gene of OrMVwas used to investigate the molecular mechanisms underlying the evolution of this virus. The 36 OrMV isolates fell into two groups which have significant subpopulation differentiation with an FST value of 0.470. One isolate was identified as a recombinant and the other 35 recombination-free isolates could be divided into two major clades under different evolutionary constraints with dN/dS values of 0.055 and 0.028, respectively, indicating a role of purifying selection in the differentiation of OrMV. In addition, the results from analysis of molecular variance (AMOVA) indicated that the effect of host species on the genetic divergence of OrMV is greater than that of geography. Furthermore, OrMV isolates from the genera Ornithogalum, Lachenalia and Diuri tended to group together, indicating that OrMV diversification was maintained, in part, by host-driven adaptation.

11.
Arch Virol ; 163(5): 1383-1386, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29392500

RESUMO

The complete sequence of a narcissus virus isolated from the Netherlands (Narv-NL) was determined to be 8172 nucleotides in length with an open reading frame encoding for 2624 amino acids. Phylogenetic analysis indicates that Narv-NL is clustered with high confidence among representative members from the genus Macluravirus, including artichoke latent virus (ArLV) and Chinese yam necrotic mosaic virus (CYNMV). Sequence analyses indicated Narv-NL shares 67%-69% nucleotide and 51%-68% amino acid sequence identity with ArLV and CYNMV either in the complete ORF or the coat protein (CP) gene, whereas it had 81%-99 % nucleotide and 80%-99 % amino acid sequence identity with the corresponding CP sequences of narcissus latent virus (NLV) isolates, suggesting that Narv-NL is a member of NLV. To our knowledge, this is the first report of the complete sequence of a NLV isolate.


Assuntos
Genoma Viral , Narcissus/virologia , Potyviridae/genética , Proteínas do Capsídeo/genética , Países Baixos , Fases de Leitura Aberta , Filogenia , Doenças das Plantas/virologia , RNA Viral/genética , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
12.
Med Phys ; 44(5): 1692-1706, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28206667

RESUMO

PURPOSE: The positioning accuracy of each component is important to ensure the image quality of cone-beam CT. However, accurate positioning is not easy and requires experience and time. The option is to calibrate the geometric parameters and then plug them into a reconstruction algorithm which is the preferred solution in practice. In this case, the image quality is determined by the accuracy and precision of the calibration method. This work describes a method to independently calibrate an imaging system in each pose (projection angle) for a cone-beam CT with a nonideal circular trajectory. METHODS: The calibration method uses a phantom with 12 beads on 2 planes that are observed on the radiographic images. This pose-independent calibration method (PIC) can decorrelate the relationships among the geometric parameters so that the parameters can be estimated one-by-one. This simplifies the calibration process. Besides the pose-independent calibration method, this paper also describes an extended calibration method with additional constraints on the system geometry. Both methods are validated with numerical simulations and then experimentally on a practical system with a scanning object loosely supported by rotating wheels. The object rotates during the CT data acquisition. The angular and pose information of the CT system are not accurately known a priori in this case. RESULTS: The numerical simulations and the experiments both provide satisfactory results. The relative error of the calibrated source-to-detector distance in the simulation is less than 0.1%. The errors in the calibrated roll, pitch, and yaw angles are less than 0.04°. A sensitivity study using various bead position uncertainties in random directions shows that the pose-independent calibration method is robust to measurement errors. Tests were also done with a nonideal circular trajectory for further validation. Images reconstructed using the geometric parameters from both the pose-independent and the extended calibration methods were free of artifacts and blur from misalignment. All these results demonstrate the effectiveness of these methods. CONCLUSIONS: The PIC method can be used to independently calibrate the geometric parameters of a cone-beam CT view-by-view. Thus, the PIC method can be implemented on commonly used systems such as circular, nonideal circular or C-arm cone-beam CTs. The PIC method can also be useful for some irregularly configured CT systems to fulfill special imaging requirements, for example, a CT system when the x ray source or the rotating platform cannot be easily located. The PIC method will reduce the costs of ensuring very precise mechanics and the labor in fine tuning CT systems.


Assuntos
Algoritmos , Tomografia Computadorizada de Feixe Cônico , Processamento de Imagem Assistida por Computador , Calibragem , Humanos , Imagens de Fantasmas
13.
Nanomaterials (Basel) ; 6(11)2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-28335331

RESUMO

The electrocatalytic activities of Mn3O4/C composites are studied in lithium-oxygen (Li-O2) batteries as cathode catalysts. The Mn3O4/C composites are fabricated using ultrasonic spray pyrolysis (USP) with organic surfactants as the carbon sources. The physical and electrochemical performance of the composites is characterized by X-ray diffraction, scanning electron microscopy, particle size analysis, Brunauer-Emmett-Teller (BET) measurements, elemental analysis, galvanostatic charge-discharge methods and rotating ring-disk electrode (RRDE) measurements. The electrochemical tests demonstrate that the Mn3O4/C composite that is prepared using Trition X-114 (TX114) surfactant has higher activity as a bi-functional catalyst and delivers better oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic performance in Li-O2 batteries because there is a larger surface area and particles are homogeneous with a meso/macro porous structure. The rate constant (kf) for the production of superoxide radical (O2•-) and the propylene carbonate (PC)-electrolyte decomposition rate constant (k) for M3O4/C and Super P electrodes are measured using RRDE experiments and analysis in the 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF6)/PC electrolyte. The results show that TX114 has higher electrocatalytic activity for the first step of ORR to generate O2•- and produces a faster PC-electrolyte decomposition rate.

14.
Nanomaterials (Basel) ; 6(1)2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-28344278

RESUMO

The electrocatalytic activities of the MnO2/C composites are examined in Li-O2 cells as the cathode catalysts. Hierarchically mesoporous carbon-supported manganese oxide (MnO2/C) composites are prepared using a combination of soft template and hydrothermal methods. The composites are characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, small angle X-ray scattering, The Brunauer-Emmett-Teller (BET) measurements, galvanostatic charge-discharge methods, and rotating ring-disk electrode (RRDE) measurements. The electrochemical tests indicate that the MnO2/C composites have excellent catalytic activity towards oxygen reduction reactions (ORRs) due to the larger surface area of ordered mesoporous carbon and higher catalytic activity of MnO2. The O2 solubility, diffusion rates of O2 and O2•- coefficients (DO2 and DO-2), the rate constant (kf) for producing O2•-, and the propylene carbonate (PC)-electrolyte decomposition rate constant (k) of the MnO2/C material were measured by RRDE experiments in the 0.1 M TBAPF6/PC electrolyte. The values of kf and k for MnO2/C are 4.29 × 10-2 cm·s-1 and 2.6 s-1, respectively. The results indicate that the MnO2/C cathode catalyst has higher electrocatalytic activity for the first step of ORR to produce O2•- and achieves a faster PC-electrolyte decomposition rate.

15.
J Chemother ; 26(5): 306-11, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24075685

RESUMO

This study sought to investigate the efficacy and tolerability of the regimen of low-dose gemcitabine combined with carboplatin in chemo-naïve patients with non-small cell lung cancer (NSCLC). The study involved 37 chemo-naive patients with unresectable stage IIIB or stage IV NSCLC. The predominant histological type was squamous carcinoma (22/37), and the performance status (PS) was 2 in 23 patients (62%). All received gemcitabine, 250 mg/m(2) in 6-hour infusion on days 1 and 8 plus carboplatin area under the curve (AUC)  =  5 on day 1, every 28 days. The overall response rate (ORR) was 62·2% and disease stabilization was achieved in 21·6% of the patients. After a median follow-up duration of 13 months, the median overall survival (OS) time was 14·0 months (95% CI 13·3-16·6 months), and the median progression-free survival (PFS) time was 7·0 months (95% CI 6·1-8·9 months). Hematological toxicities were well-tolerated with the development of grade 3/4 neutropenia and thrombocytopenia in 10·3 and 10·3% of patients respectively, and the gastrointestinal toxicities were mild.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Carboplatina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/patologia , Terapia Combinada , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Progressão da Doença , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Gencitabina
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