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1.
Sensors (Basel) ; 23(7)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37050734

RESUMO

The identification of ground intrusion is a key and important technology in the national public security field. In this paper, a novel variational mode decomposition (VMD) and Hilbert transform (HT) is proposed for the classification of seismic signals generated by ground intrusion activities using a seismic sensing system. Firstly, the representative seismic data, including bicycles, vehicles, footsteps, excavations, and environmental noises, were collected through the designed experiment. Secondly, each original datum is decomposed through VMD and five Band-limited intrinsic mode functions (BIMF) are obtained, respectively, which will be used to generate a corresponding marginal spectrum that can reflect the actual frequency component of the signal accurately by HT. Then, three features related to the marginal spectrum, including marginal spectrum energy, marginal spectrum entropy, and marginal spectrum dominant frequency, are extracted for the analysis of the multi-classification using the support vector machine (SVM) classifier with the LIBSVM library. For the sake of testing and verifying the effectiveness of the proposed variational mode decomposition and Hilbert transform (VMD-HT) technique, the evaluation indicators including accuracy, precision, recall, and F1-Score are used and the results are compared with the time domain, frequency domain, ensemble empirical mode decomposition (EEMD), and empirical wavelet transform (EWT) combined with the HT analysis method. The performance of the VMD-HT method for ground intrusion activity classification provides an average value of 99.50%, 98.76%, 98.76%, and 98.75% for the four evaluation indicators, which are higher than all the other contrasted methods.

2.
Sci Rep ; 12(1): 19959, 2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36402912

RESUMO

Cinnamon aqueous extract's active substance base remains unclear and its mechanisms, mainly the therapeutic target of anti-Alzheimer's disease (AD)-related GABAergic synaptic dysfunction, remain unclear. Here, 30 chemical components were identified in the aqueous extract of cinnamon using LC/MS; secondly, we explored the brain-targeting components of the aqueous extract of cinnamon, and 17 components had a good absorption due to the blood-brain barrier (BBB) limitation; thirdly, further clustering analysis of active ingredient targets by network pharmacology showed that the GABA pathway with GABRG2 as the core target was significantly enriched; then, we used prominent protein-protein interactions (PPI), relying on a protein-metabolite network, and identified the GABRA1, GABRB2 and GABRA5 as the closest targets to GABRG2; finally, the affinity between the target and its cognate active compound was predicted by molecular docking. In general, we screened five components, methyl cinnamate, propyl cinnamate, ( +)-procyanidin B2, procyanidin B1, and myristicin as the brain synapse-targeting active substances of cinnamon using a systematic strategy, and identified GABRA1, GABRB2, GABRA5 and GABRG2 as core therapeutic targets of cinnamon against Alzheimer's disease-related GABAergic synaptic dysfunction. Exploring the mechanism of cinnamon' activities through multi-components and multiple targets strategies promise to reduce the threat of single- target and symptom-based drug discovery failure.


Assuntos
Doença de Alzheimer , Medicamentos de Ervas Chinesas , Cinnamomum zeylanicum , Simulação de Acoplamento Molecular , Farmacologia em Rede , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Medicamentos de Ervas Chinesas/farmacologia
3.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(8): 1058-1064, 2022 Aug 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36097773

RESUMO

OBJECTIVES: The automatic delineation of organs at risk (OARs) can help doctors make radiotherapy plans efficiently and accurately, and effectively improve the accuracy of radiotherapy and the therapeutic effect. Therefore, this study aims to propose an automatic delineation method for OARs in cervical cancer scenarios of both after-loading and external irradiation. At the same time, the similarity of OARs structure between different scenes is used to improve the segmentation accuracy of OARs in difficult segmentations. METHODS: Our ensemble model adopted the strategy of ensemble learning. The model obtained from the pre-training based on the after-loading and external irradiation was introduced into the integrated model as a feature extraction module. The data in different scenes were trained alternately, and the personalized features of the OARs within the model and the common features of the OARs between scenes were introduced. Computer tomography (CT) images for 84 cases of after-loading and 46 cases of external irradiation were collected as the train data set. Five-fold cross-validation was adopted to split training sets and test sets. The five-fold average dice similarity coefficient (DSC) served as the figure-of-merit in evaluating the segmentation model. RESULTS: The DSCs of the OARs (the rectum and bladder in the after-loading images and the bladder in the external irradiation images) were higher than 0.7. Compared with using an independent residual U-net (convolutional networks for biomedical image segmentation) model [residual U-net (Res-Unet)] delineate OARs, the proposed model can effectively improve the segmentation performance of difficult OARs (the sigmoid in the after-loading CT images and the rectum in the external irradiation images), and the DSCs were increased by more than 3%. CONCLUSIONS: Comparing to the dedicated models, our ensemble model achieves the comparable result in segmentation of OARs for different treatment options in cervical cancer radiotherapy, which may be shorten time for doctors to sketch OARs and improve doctor's work efficiency.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Órgãos em Risco/efeitos da radiação , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias do Colo do Útero/radioterapia
4.
BMC Complement Med Ther ; 22(1): 115, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35468773

RESUMO

BACKGROUND: Trans-cinnamaldehyde (TCA) is one of the main pharmaceutical ingredients of Cinnamomum cassia Presl, which has been shown to have therapeutic effects on a variety of cardiovascular diseases. This study was carried out to characterize and reveal the underlying mechanisms of the protective effects of TCA against cardiac hypertrophy. METHODS: We used phenylephrine (PE) to induce cardiac hypertrophy and treated with TCA in vivo and in vitro. In neonatal rat cardiomyocytes (NRCMs), RNA sequencing and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were carried out to identify potential pathways of TCA. Then, the phosphorylation and nuclear localization of calcium/calmodulin-dependent protein kinase II (CaMKII) and extracellular signal-related kinase (ERK) were detected. In adult mouse cardiomyocytes (AMCMs), calcium transients, calcium sparks, sarcomere shortening and the phosphorylation of several key proteins for calcium handling were evaluated. For mouse in vivo experiments, cardiac hypertrophy was evaluated by assessing morphological changes, echocardiographic parameters, and the expression of hypertrophic genes and proteins. RESULTS: TCA suppressed PE-induced cardiac hypertrophy and the phosphorylation and nuclear localization of CaMKII and ERK in NRCMs. Our data also demonstrate that TCA blocked the hyperphosphorylation of ryanodine receptor type 2 (RyR2) and phospholamban (PLN) and restored Ca2+ handling and sarcomere shortening in AMCMs. Moreover, our data revealed that TCA alleviated PE-induced cardiac hypertrophy in adult mice and downregulated the phosphorylation of CaMKII and ERK. CONCLUSION: TCA has a protective effect against PE-induced cardiac hypertrophy that may be associated with the inhibition of the CaMKII/ERK pathway.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Miócitos Cardíacos , Acroleína/análogos & derivados , Animais , Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/tratamento farmacológico , Cardiomegalia/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Fenilefrina/efeitos adversos , Fenilefrina/metabolismo , Ratos , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/farmacologia
5.
Sci Total Environ ; 814: 152681, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-34973326

RESUMO

Polyethylene microplastics (PE-MPs) and glyphosate (GLY) occur widely and have toxic characteristics, resulting in increased research interest. In this study, common carp were used to assess the individual and combined toxicity of PE-MPs (0, 1.5, or 4.5 mg/L) and GLY (0, 5, or 15 mg/L) on the brain-gut axis. After 60 days of exposure, the developmental toxicity, blood-brain barrier (BBB), locomotor behavior, intestinal barrier (physical barrier, chemical barrier, microbial barrier), and intestinal content metabolism of common carp were evaluated. Results showed that 15 mg/L of GLY exposure significantly reduced the mRNA expression of tight-junction genes (occludin, claudin-2, and ZO-1) in the brain, and acetylcholinesterase (AChE) activity was clearly inhibited by high concentrations of GLY. However, different concentrations of PE-MPs had no significant effect on the activity of AChE. Furthermore, the free-swimming behavior of common carp was distinctly inhibited by treatment with a combination of 15 mg/L GLY and 4.5 mg/L PE-MPs. Histological studies indicated that PE-MPs alone and in combination with GLY could disrupt the physical and chemical intestinal barriers of common carp. Additionally, the abundance and diversity of gut microbiota in common carp were significantly changed when exposed to a combination of PE-MPs and GLY. Metabolomics further revealed that PE-MPs combined with GLY triggered metabolic changes and that differential metabolites were related to amino acid and lipid metabolism. These findings illustrate that exposure to PE-MPs or GLY alone is toxic to fish and results in physiological changes to the brain-gut axis. This work offers a robust analysis to understand the mechanisms underlying GLY and MP-induced aquatic toxicity.


Assuntos
Carpas , Poluentes Químicos da Água , Acetilcolinesterase , Animais , Glicina/análogos & derivados , Homeostase , Microplásticos , Plásticos , Polietileno/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Glifosato
6.
Eur J Pharmacol ; 914: 174687, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34883072

RESUMO

BACKGROUND: Trans-cinnamaldehyde (TCA) is a main compound of Cinnamomum cassia, used in traditional Chinese medicine to treat many ailments. Increasing evidence has demonstrated the therapeutic effects of TCA in cardiovascular diseases. PURPOSE: The present study aimed to determine whether TCA exerts antihypertrophic effects in vitro and in vivo and to elucidate the underlying mechanisms of these effects. METHODS: Neonatal rat cardiac myocytes (NRCMs) and adult mouse cardiac myocytes (AMCMs) were treated with 50 µΜ phenylephrine (PE) for 48 h. Tubulin detyrosination, store-operated Ca2+ entry (SOCE), stromal interaction molecule-1 (STIM1)/Orai1 translocation, and calcineurin/nuclear factor of activated T-cells (NFAT) signaling pathways were analyzed in NRCMs. Meanwhile, tubulin detyrosination, junctophilin-2, T-tubule distribution pattern, Ca2+ handling, and sarcomere shortening were observed in AMCMs. Male C57BL/6 mice were stimulated with PE (70 mg/kg per day) with or without TCA treatment for 2 weeks. Cardiac hypertrophy and tubulin detyrosination were also assessed. RESULTS: TCA was confirmed to alleviate cardiac hypertrophy induced by PE stimulation in vitro and in vivo. PE-induced cardiac hypertrophy was associated with excessive tubulin detyrosination and overexpression of vasohibin 1 (VASH1) and small vasohibin binding protein (SVBP), two key proteins responsible for tubulin detyrosination. These effects were largely blocked by TCA administration. PE treatment also enhanced SOCE with massive translocation of STIM1 and Orai1, Ca2+ mishandling, reduced sarcomere shortening, junctophilin-2, and T-tubule redistribution, all of which were significantly ameliorated by TCA administration. CONCLUSION: Our study indicated that the therapeutic effects of TCA against cardiac hypertrophy may be associated with its ability to reduce tubulin detyrosination.


Assuntos
Acroleína/análogos & derivados , Cardiomegalia , Microtúbulos , Miócitos Cardíacos , Tubulina (Proteína)/metabolismo , Acroleína/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Cardiomegalia/tratamento farmacológico , Cardiomegalia/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/ultraestrutura , Ratos , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento , Moduladores de Tubulina/farmacologia
7.
Med Phys ; 48(4): 1771-1780, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33555048

RESUMO

PURPOSE: This study aimed to improve the accuracy of the hippocampus segmentation through multitask edge-aware learning. METHOD: We developed a multitask framework for computerized hippocampus segmentation. We used three-dimensional (3D) U-net as our backbone model with two training objectives: (a) to minimize the difference between the targeted binary mask and the model prediction; and (b) to optimize an auxiliary edge-prediction task which is designed to guide the model detection of the weak boundary of the hippocampus in model optimization. To balance the multiple task objectives, we proposed an improved gradient normalization by adaptively adjusting the weight of losses from different tasks. A total of 247 T1-weighted MRIs including 131 without contrast and 116 with contrast were collected from 247 patients to train and validate the proposed method. Segmentation was quantitatively evaluated with the dice coefficient (Dice), Hausdorff distance (HD), and average Hausdorff distance (AVD). The 3D U-net was used for baseline comparison. We used a Wilcoxon signed-rank test to compare repeated measurements (Dice, HD, and AVD) by different segmentations. RESULTS: Through fivefold cross-validation, our multitask edge-aware learning achieved Dice of 0.8483 ± 0.0036, HD of 7.5706 ± 1.2330 mm, and AVD of 0.1522 ± 0.0165 mm, respectively. Conversely, the baseline results were 0.8340 ± 0.0072, 10.4631 ± 2.3736 mm, and 0.1884 ± 0.0286 mm, respectively. With a Wilcoxon signed-rank test, we found that the differences between our method and the baseline were statistically significant (P < 0.05). CONCLUSION: Our results demonstrated the efficiency of multitask edge-aware learning in hippocampus segmentation for hippocampal sparing whole-brain radiotherapy. The proposed framework may also be useful for other low-contrast small organ segmentations on medical imaging modalities.


Assuntos
Hipocampo , Imageamento por Ressonância Magnética , Hipocampo/diagnóstico por imagem , Humanos , Aprendizagem
8.
Adv Mater ; 31(25): e1808226, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31074118

RESUMO

Inspired by flagellate microorganisms in nature, the microhelix is considered as an ideal model for transportation in fluid environment with low Reynolds number. However, how to promote the swimming and loading capabilities of microhelices with controllable geometries remains challenging. In this study, a novel kind of conical hollow microhelices is proposed and a method is developed to rapidly fabricate these microhelices with controllable parameters by femtosecond vortex beams generated from spatial light modulation along helical scanning. Conical hollow microhelices with designable heights (H = 45-75 µm), diameters (D = 6-18 µm), pitch numbers (Pi = 2-4), taper angles (T = 0.1-0.6 rad), and pitch periods (ΔP = 10-30 µm) are efficiently fabricated. In addition, compared with straight microhelices, the forward swimming capability of conical microhelices increases by 50% and the lateral drift of the conical hollow microhelices is reduced by 70%. Finally, the capabilities of these conical hollow microhelices for nanocargo loading and release by the inner hollow core, as well as transportation of neural stem cells by the outer surface are demonstrated. This work provides new insights into faster and simultaneous transportation of multicargoes for hybrid drug delivery, targeted therapy, and noninvasive surgery in vivo.

9.
Opt Lett ; 43(21): 5335-5338, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30383000

RESUMO

In this Letter, parallel writing of silver microwire (AgMW) arrays based on femtosecond laser multiphoton reduction (MPR) is realized by modulating a femtosecond laser beam into a multifoci pattern with a spatial light modulator (SLM). Arbitrarily distributed multifoci are generated with predesigned holograms loaded on a SLM for MPR. The experimental parameters for the desired fabrication of AgMWs with multifoci are systematically investigated and optimized. On this basis, different AgMW patterns are dynamically and simultaneously fabricated by loading different holograms onto a high-frequency refreshed SLM in sequence. The quantity and distribution of multifoci can be controlled dynamically by the SLM in the fabrication process, and even the intensity of individual focus is dynamically modulated by the control of the gray level of holograms. Finally, the potential application of this flexible and rapid AgMW fabrication method in microheater fabrication is demonstrated. The microheaters exhibit a controllable temperature gradient after energized.

10.
Mol Plant ; 11(10): 1278-1291, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30130577

RESUMO

In plants, stomatal movements are tightly controlled by changes in cellular turgor pressure. Carbohydrates produced by glycolysis and the tricarboxylic acid cycle play an important role in regulating turgor pressure. Here, we describe an Arabidopsis mutant, bzu1, isolated in a screen for elevated leaf temperature in response to drought stress, which displays smaller stomatal pores and higher drought resistance than wild-type plants. BZU1 encodes a known acetyl-coenzyme A synthetase, ACN1, which acts in the first step of a metabolic pathway converting acetate to malate in peroxisomes. We showed that BZU1/ACN1-mediated acetate-to-malate conversion provides a shunt that plays an important role in osmoregulation of stomatal turgor. We found that the smaller stomatal pores in the bzu1 mutant are a consequence of reduced accumulation of malate, which acts as an osmoticum and/or a signaling molecule in the control of turgor pressure within guard cells, and these results provided new genetic evidence for malate-regulated stomatal movement. Collectively, our results indicate that a peroxisomal BZU1/ACN1-mediated acetate-malate shunt regulates drought resistance by controlling the turgor pressure of guard cells in Arabidopsis.


Assuntos
Arabidopsis/metabolismo , Malatos/metabolismo , Peroxissomos/metabolismo , Estômatos de Plantas/metabolismo , Adaptação Fisiológica , Arabidopsis/citologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Secas , Mutação , Osmorregulação , Transpiração Vegetal
11.
Opt Lett ; 42(4): 743-746, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28198854

RESUMO

In this Letter, superposed Bessel beams (SBBs) are realized by alternatively imprinting holograms of opposite-order Bessel beams along the radial direction on a spatial light modulator. The propagation invariance and non-rotation properties of SBBs are theoretically predicted and experimentally demonstrated. The focusing property of SBBs with a high numerical aperture (NA) objective is investigated with the Debye vectorial diffraction theory. Near the focal plane, a circularly distributed multiple foci pattern is achieved. The multiple foci generated from SBBs are adopted in a two-photon fabrication system, and micropattern fabrication by a single exposure is demonstrated. Facile fabrication of three-dimensional microstructures with SBBs is realized by dynamically controlling the number of focal spots, and the diameter and rotation of the focal pattern.

12.
Shanghai Kou Qiang Yi Xue ; 22(3): 305-9, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23852062

RESUMO

PURPOSE: To investigate the feasibility of occlusal reconstruction with IPS e.max Press for patients suffering from severely worn dentition, and to summarize the technological experience. METHODS: IPS e.max Press was used to reconstruct occlusion for one patient with severely worn dentition. Provisional restorations were fitted in worn teeth to rehabilitate the vertical dimension and centric relationship almost 3 months before final treatment. Face bow was used to transfer the general information of provisional restorations to articulator, including the plane of occlusion, anatomical outline and intercuspal position of teeth. RESULTS: After 24 months of follow-up, the masticatory efficiency and facial appearance were improved significantly, and TMJ disorder was not observed. The patient was satisfied with the prostheses. CONCLUSIONS: IPS e.max Press is an effective and reliable treatment of occlusal reconstruction.The short term effect is promoting. Supported by Clinical Medical Research Fund of Bureau of Science and Technology, Jiangsu Province(SBL201230169).


Assuntos
Articuladores Dentários , Dentição , Oclusão Dentária , Porcelana Dentária , Humanos , Dimensão Vertical
13.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 31(2): 113-7, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23662547

RESUMO

This paper introduced the key points in fabricating anterior esthetic restorations with all ceramic materials, including pre-operative smile design, standard tooth preparation, provisional restoration fabrication, all ceramic materials selection, all ceramic restoration bonding, ceramic crack and fracture prevention. And then, the authors summarized and reviewed the clinical common problems in anterior esthetic restorations.


Assuntos
Cerâmica , Porcelana Dentária , Estética , Humanos
14.
Shanghai Kou Qiang Yi Xue ; 21(6): 691-4, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23364558

RESUMO

PURPOSE: To investigate the clinical effect of repairing posterior residual crown using titanium alloy post combined with composite resin core technique. METHODS: Twenty-one patients (26 residual crown) with perfect root canal therapy were selected. Modern bonding technique was used to build up the core with titanium alloy post and flow composite resin together for crown restoration. RESULTS: After ten years of clinical observation, only 4 cases among the 21 patients failed in restoration. The rate of success was 85%. X-ray showed that the periapical alveolar bone density was enhanced after restoration. CONCLUSIONS: Standard root canal therapy and effective post-core strengthening can restore the function of the residual crown and retain the tooth.


Assuntos
Coroas , Técnica para Retentor Intrarradicular , Resinas Compostas , Humanos , Tratamento do Canal Radicular , Coroa do Dente
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