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1.
Sensors (Basel) ; 23(16)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37631761

RESUMO

In indoor environments, reverberation can distort the signalseceived by active noise cancelation devices, posing a challenge to sound classification. Therefore, we combined three speech spectral features based on different frequency scales into a densely connected network (DenseNet) to accomplish sound classification with reverberation effects. We adopted the DenseNet structure to make the model lightweight A dataset was created based on experimental and simulation methods, andhe classification goal was to distinguish between music signals, song signals, and speech signals. Using this framework, effectivexperiments were conducted. It was shown that the classification accuracy of the approach based on DenseNet and fused features reached 95.90%, betterhan the results based on other convolutional neural networks (CNNs). The size of the optimized DenseNet model is only 3.09 MB, which is only 7.76% of the size before optimization. We migrated the model to the Android platform. The modified model can discriminate sound clips faster on Android thanhe network before the modification. This shows that the approach based on DenseNet and fused features can dealith sound classification tasks in different indoor scenes, and the lightweight model can be deployed on embedded devices.

2.
Sensors (Basel) ; 23(15)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37571671

RESUMO

In the shallow-water waveguide environment, the tonal signals radiated by moving targets carry modal interference and Doppler shift information. The modal interference can be used to obtain the time of the closest point of approach (tCPA) and the ratio of the range at the closest point of approach to the velocity of the source (rCPA/v). However, parameters rCPA and v cannot be solved separately. When tCPA is known, the rCPA and the v of the target can be obtained theoretically by using the Doppler information. However, when the Doppler frequency shift is small or at a low signal-to-noise ratio, there will be a strong parametric coupling between rCPA and v. In order to solve the above parameter coupling problem, a target motion parameter estimation method from tonal signals with a single hydrophone is proposed in this paper. The method uses the Doppler and modal interference information carried by the tonal signals to obtain two different parametric coupling curves. Then, the parametric coupling curves can be used to estimate the two motion parameters. Simulation experiments verified the rationality of this method. The proposed method was applied to the SWellEx-96 and speedboat experiments, and the estimation errors of the motion parameters were within 10%, which shows the method is effective in its practical applications.

6.
Appl Biochem Biotechnol ; 195(1): 505-518, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36094649

RESUMO

Transarterial embolization (TAE) constitutes the gold standard for the treatment of hepatocellular carcinoma. The effect of combination of TAE and peglated-H1/HGFK1 nanoparticles was explored on hepatocellular carcinoma. MTT and Annexin V-FITC were used to determine the cell viability and apoptosis of HepG2, ml-1, LO2, and VX2 cells after the treatment of HGFK1. Next, the orthotopic rabbit was selected to establish the in situ models of VX2 hepatocellular carcinoma. Nanoparticles were synthesized with peglated-PH1 and used to deliver HGFK1 overexpressing plasmids. MRI was performed to monitor tumor volume after being treated with TAE. The protein expression levels of CD31, CD90, and Ki67 were determined by immunohistochemistry. H&E and TUNEL staining were used to determine the necrosis and apoptosis in vivo. HGFK1 significantly inhibited the proliferation and increased the apoptosis of HepG2 and ml-1 cells (P < 0.05). MRI on 14 days after modeling suggested that the tumor showed ring enhancement. MRI on 7 days and 14 days after interventional therapy showed that tumor volume was significantly inhibited after the treatment with TAE and HGFK1 (P < 0.05). The immunohistochemical results 7 days after interventional therapy indicated that the expressions of CD31, CD90, and Ki67 were significantly lower after treatment with TAE and HGFK1 (P < 0.05). TAE and HGFK1 all extended the survival period of rabbits (P < 0.05). PH1/HGFK1 nanoparticle is an innovative and effective embolic agent, which could limit angiogenesis post-TAE treatment. The combination of TAE with PH1/HGFK1 is a promising strategy and might alter the way that surgeons manage hepatocellular carcinoma (HCC).


Assuntos
Carcinoma Hepatocelular , Embolização Terapêutica , Neoplasias Hepáticas , Nanopartículas , Animais , Coelhos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Antígeno Ki-67/genética , Nanopartículas/uso terapêutico
7.
JASA Express Lett ; 2(5): 056002, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-36154066

RESUMO

Experimental data indicate that in a sloped area, the value of ß abruptly changes before and after a given source arrives at the closest point of approach to the hydrophone, which has not been previously reported. The adiabatic approximation is employed to explain the above abrupt change in ß, and it is found that the azimuthal variance in the sound path is the reason for this phenomenon. Simulations are performed to confirm the model and experimental data, and perfect agreement is achieved. This work suggests that ß should be carefully set in related applications in a sloped area.


Assuntos
Localização de Som , Som , Espectrografia do Som
8.
Int J Med Robot ; 18(6): e2444, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35923081

RESUMO

BACKGROUND: Endovascular intervention is an important minimally invasive surgery that requires professional skills to operate surgical instruments. Such skills are mainly gained through the traditional training paradigm of "see one, do one, teach one", rather than the guidewire simulation system. METHODS: To identify limitations of existing guidewire simulation research and suggest further research orientations, a comprehensive search on literature published from 2007 to 2021 is performed in 11 selected electronic databases. Through our scrutiny and filtration, 34 articles are selected as major studies for careful examinations. RESULTS: We identify challenges faced in the field of endovascular intervention guidewire simulation. We examine and classify guidewire simulation techniques (including guidewire models, collision detection methods and collision response methods), accuracy evaluation methods, error sources, and performance optimization methods. CONCLUSIONS: Guidewire simulation can satisfy the urgent need to train surgeons, thus more efforts should be dedicated enabling its wide application in clinical environment.


Assuntos
Procedimentos Endovasculares , Cirurgiões , Humanos , Competência Clínica , Simulação por Computador , Cateterismo , Procedimentos Endovasculares/educação
9.
Transl Res ; 249: 128-143, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35850446

RESUMO

Despite progress in prevention and treatment, colorectal cancer (CRC) remains the third most common malignancy worldwide and the second most common cause of cancer death in 2020. To evaluate various characteristics of human CRC, a variety of mouse models have been established. Transplant mouse models have distinct advantages in studying the clinical behavior and therapeutic progress of CRC. Host, xenograft, and transplantation routes are the basis of transplant mouse models. As the effects of the tumor microenvironment and the systemic environment on cancer cells are gradually revealed, 3 key elements of transplanted CRC mouse models have been revolutionized. This has led to the development of humanized mice, patient-derived xenografts, and orthotopic transplants that reflect the human systemic environment, patient's tumor of origin, and tumor growth microenvironments in immunodeficient mice, respectively. These milestone events have allowed for great progress in tumor biology and the treatment of CRC. This article reviews the evolution of these events and points out their strengths and weaknesses as innovative and useful preclinical tools to study CRC progression and metastasis and to exploit novel treatment schedules by establishing a testing platform. This review article depicts the optimal transplanted CRC mouse models and emphasizes the significance of surgical models in the study of CRC behavior and treatment response.


Assuntos
Neoplasias Colorretais , Microambiente Tumoral , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Camundongos
11.
Int J Comput Assist Radiol Surg ; 17(6): 1115-1124, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35384552

RESUMO

PURPOSE: Clinical rib fracture diagnosis via computed tomography (CT) screening has attracted much attention in recent years. However, automated and accurate segmentation solutions remain a challenging task due to the large sets of 3D CT data to deal with. Down-sampling is often required to face computer constraints, but the performance of the segmentation may decrease in this case. METHODS: A new multi-angle projection network (MAPNet) method is proposed for accurately segmenting rib fractures by means of a deep learning approach. The proposed method incorporates multi-angle projection images to complementarily and comprehensively extract the rib characteristics using a rib extraction (RE) module and the fracture features using a fracture segmentation (FS) module. A multi-angle projection fusion (MPF) module is designed for fusing multi-angle spatial features. RESULTS: It is shown that MAPNet can capture more detailed rib fracture features than some commonly used segmentation networks. Our method achieves a better performance in accuracy (88.06 ± 6.97%), sensitivity (89.26 ± 5.69%), specificity (87.58% ± 7.66%) and in terms of classical criteria like dice (85.41 ± 3.35%), intersection over union (IoU, 80.37 ± 4.63%), and Hausdorff distance (HD, 4.34 ± 3.1). CONCLUSION: We propose a rib fracture segmentation technique to deal with the problem of automatic fracture diagnosis. The proposed method avoids the down-sampling of 3D CT data through a projection technique. Experimental results show that it has excellent potential for clinical applications.


Assuntos
Aprendizado Profundo , Fraturas das Costelas , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Fraturas das Costelas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
12.
Int J Biol Markers ; 37(2): 140-148, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35296171

RESUMO

BACKGROUND: This study aimed to investigate the expression pattern and prognostic significance of HOXB13 in rectal cancer. METHODS: HOXB13 expression in rectal cancer and normal adjacent tissues was detected by reverse transcriptase-polymerase chain reaction and immunohistochemistry, and its clinicopathological characteristics and prognosis were statistically tested. Furthermore, we evaluated the association between tumor immune infiltrating cells and HOXB13 using the tumor immune estimation resource (TIMER) database. The potential biological mechanism associated with HOXB13 overexpression was investigated by gene set enrichment analysis (GSEA). RESULTS: The expression of HOXB13 messenger RNA and protein in human rectal cancer tissues were significantly higher than those in the normal adjacent tissues (P < 0.05). HOXB13 expression was significantly correlated with depth of invasion, lymphatic invasion, lymph node metastasis, distant metastasis, and pathological tumor node metastasis stage (P < 0.05). Kaplan-Meier survival curves confirmed that HOXB13 overexpression was correlated negatively with overall survival and disease-free survival in rectal cancer (P < 0.05). Also, multivariate Cox regression analysis demonstrated that HOXB13 expression, age, and lymphatic invasion were independent prognostic factors in rectal cancer (P < 0.05). Plus, the results from the TIMER database indicated that HOXB13 expression has a significant association with several immune cell infiltrates. Finally, the GSEA results indicated that HOXB13 participated in the various immune-associated processes, including natural killer cell-mediated cytotoxicity and the T-cell receptor signaling pathway. CONCLUSION: Our study showed an essential role of HOXB13 in rectal cancer immunity and prognosis. Significantly, the overexpression of HOXB13 leads to the worse prognosis for patients with rectal cancer, which will contribute to understanding molecular mechanisms associated with tumor pathogenesis and prognosis in this disease.


Assuntos
Proteínas de Homeodomínio , Neoplasias Retais , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proteínas de Homeodomínio/biossíntese , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Imuno-Histoquímica , Prognóstico , Neoplasias Retais/genética , Neoplasias Retais/metabolismo
13.
Anticancer Res ; 41(11): 5507-5515, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34732421

RESUMO

BACKGROUND/AIM: The aim of the present study was to correlate the survival response to regional arterial-perfusion chemotherapy (RAPC) with Borrmann classification in patients with gastric cancer. PATIENTS AND METHODS: The survival response of 270 patients with advanced gastric cancer treated with RAPC was analyzed and Borrmann classification of the tumors was retrospectively correlated to survival. RESULTS: The median survival time of RAPC-treated patients with Borrmann type I/II was 53 months compared with 19 and 12 months for those with Borrmann type III and IV, respectively (p<0.001). CONCLUSION: Borrmann classification is a potential indicator to predict prognosis of patients with advanced gastric cancer treated with RAPC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Quimioterapia do Câncer por Perfusão Regional , Terapia Neoadjuvante , Neoplasias Gástricas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante , Quimioterapia do Câncer por Perfusão Regional/efeitos adversos , Quimioterapia do Câncer por Perfusão Regional/mortalidade , Feminino , Gastrectomia , Humanos , Excisão de Linfonodo , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Terapia Neoadjuvante/mortalidade , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Fatores de Tempo , Resultado do Tratamento
14.
Int J Biol Markers ; 36(3): 23-32, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34595980

RESUMO

PURPOSE: To study in detail the expression pattern and prognostic significance of TMPRSS4 in colorectal cancer. METHODS: The expression of TMPRSS4 protein was determined using Western blot in the colorectal cancer tissues and normal tissues. Immunohistochemistry was used to detect the TMPRSS4 expression in colorectal cancer tissues, and the clinicopathologic characteristics and prognostic significance were analyzed. RESULTS: TMPRSS4 overexpression was associated with tumor budding, lymphovascular invasion, perineural invasion, cancerous emboli, infiltration depth, lymph node metastasis, distant metastasis, and tumor node metastasis stage (P < 0.05 for all). Interestingly, TMPRSS4 expression in the tumor budding, tumor emboli, lymph node, and liver metastatic tumor samples was higher than in the paired primary tumors. In contrast, TMPRSS4 overexpression is inversely correlated with both the overall survival and the disease-free survival of the patients with colorectal cancer (P < 0.05 for both). Also, we found that TMPRSS4 is only of significance in predicting the prognosis of stage III and IV colorectal cancer, not stage I and II. CONCLUSIONS: TMPRSS4 was shown to be involved in the whole process of metastasis from tumor budding to lymph node and/or distant metastasis in colorectal cancer and predicted the unfavorable prognosis of stage III-IV, indicating that it is a novel target for the precise treatment of colorectal cancer with lymph node or distant organ metastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Humanos , Imuno-Histoquímica , Metástase Linfática , Proteínas de Membrana/genética , Estadiamento de Neoplasias , Prognóstico , Serina Endopeptidases/genética
15.
Hum Cell ; 34(6): 1812-1829, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34431063

RESUMO

Mesenchymal stem cell (MSCs)-derived exosomes have been frequently used as useful tools in disease control. This research aimed to study the function of MSC-derived exosomes (Exo) in the stemness of cancer stem cells (CSCs) of hepatocellular carcinoma (HCC) and the molecular mechanism. Exo from the procured human bone marrow-MSCs were extracted and identified. CSCs from HCC cell lines were collected. The CSCs were treated with Exo, and then the proliferation, migration, invasion, angiogenesis-stimulating and self-renewal abilities of the Hep3B-CSCs and HuH7-CSCs were significantly reduced. C5orf66-AS1 was found as the most upregulated long noncoding RNAs (lncRNAs) in CSCs after Exo treatment. The integrated bioinformatic analyses and luciferase assays suggested that C5orf66-AS1 upregulated DUSP1 expression through sequestering microRNA-127-3p (miR-127-3p). Either artificial overexpression of miR-127-3p or silencing of DUSP1 blocked the inhibitory functions of Exo in the CSCs. DUSP1 inhibition increased the phosphorylation of ERK. Similar results were reproduced in vivo where Exo reduced the growth of xenograft formed by CSCs in nude mice, and this reduction was blocked upon miR-127-3p overexpression or DUSP1 silencing. To conclude, this research reported that MSC-derived Exo block malignant behaviors of HCC-sourced CSCs through a C5orf66-AS1/miR-127-3p/DUSP1/ERK axis.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Fosfatase 1 de Especificidade Dupla/metabolismo , Exossomos/genética , Exossomos/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Células-Tronco Mesenquimais/citologia , MicroRNAs/metabolismo , Animais , Carcinoma Hepatocelular/terapia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Autorrenovação Celular/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Hepáticas/terapia , Camundongos Nus , Invasividade Neoplásica/genética , RNA Longo não Codificante
16.
Wideochir Inne Tech Maloinwazyjne ; 16(1): 83-90, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33786120

RESUMO

INTRODUCTION: Patients are at risk of abdominal rebleeding after transcatheter arterial embolization (TAE) for pancreatitis-related pseudoaneurysm, which increases the mortality rate. AIM: This study was performed to evaluate the effects of an intestinal fistula (IF) and the anatomical location of the pseudoaneurysm on abdominal rebleeding after TAE of a ruptured pseudoaneurysm associated with severe acute pancreatitis (SAP). MATERIAL AND METHODS: From February 2013 to November 2019, 24 patients with SAP-related pseudoaneurysm rupture and hemorrhage in our hospital underwent TAE. All patients' epidemiological data and related medical histories were collected and statistically analyzed. We classified the pseudoaneurysms as type I, II, and III according to their anatomical locations and as type A (without an IF) and type B (with an IF). RESULTS: The interventions for abdominal infection in patients with type I pseudoaneurysms were percutaneous drainage in 6 patients, endoscopic necrotic tissue removal in 5, and surgical necrotic tissue removal or enterostomy in none, with a rebleeding rate of 33.3% (3/9 patients). The interventions for abdominal infection in patients with type II pseudoaneurysms were percutaneous drainage in 7 patients, endoscopy in three, and surgery in one, with a rebleeding rate of 20.0% (2/10 patients). The interventions for abdominal infection in patients with type III pseudoaneurysms were percutaneous drainage in 3 patients, endoscopy in 1, and surgery in 2, with a rebleeding rate of 80.0% (4/5 patients). There was no statistically significant difference in the types of interventions for abdominal infection among patients with type I, II, and III pseudoaneurysms (p = 0.355) or in the rate of abdominal rebleeding after TAE for type III pseudoaneurysms (p = 0.111). The interventions for abdominal infection in patients with type A pseudoaneurysms were percutaneous drainage in 13 patients, endoscopy in 6, and surgery in 1, with a rebleeding rate of 22.2% (4/18 patients) and mortality rate of 11.1% (2/18 patients). The interventions for abdominal infection in patients with type B pseudoaneurysms were percutaneous drainage in 3 patients, endoscopy in 3, and surgery in 2, with a rebleeding rate of 83.3% (5/6 patients) and mortality rate of 66.7% (4/6 patients). There was no significant difference in the types of interventions for abdominal infection in patients with and without IF (p = 0.215); however, the rebleeding rate and mortality rate were significantly higher in patients with IF (p = 0.015 and 0.018, respectively). CONCLUSIONS: IF may increase the rate of abdominal rebleeding after TAE for ruptured SAP-related pseudoaneurysms, while the anatomical location of the pseudoaneurysm may not affect the rate of rebleeding after TAE.

17.
JASA Express Lett ; 1(1): 016006, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36154094

RESUMO

In this letter, a method is proposed to estimate the motion parameters of a multitonal source with a single hydrophone when only the acquisition time of the pressure field is known. Source motion parameters, including the time of closest point of approach (tCPA) and the ratio of the range at the closest point of approach to the source speed ( rCPA/v) are obtained by correlation of two resampled tonal signals. Only two tones emitted by the same source and a value of the waveguide invariant are required. The proposed method is validated by simulation and data from the SWellEx-96 experiment.

18.
J Acoust Soc Am ; 147(4): EL363, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32359287

RESUMO

A U-Net is trained to recover acoustic interference striations (AISs) from distorted ones. A random mode-coupling matrix model is introduced to generate a large number of training data quickly, which are used to train the U-Net. The performance of AIS recovery of the U-Net is tested in range-dependent waveguides with nonlinear internal waves (NLIWs). Although the random mode-coupling matrix model is not an accurate physical model, the test results show that the U-Net successfully recovers AISs under different signal-to-noise ratios and different amplitudes and widths of NLIWs for different shapes.

19.
J Acoust Soc Am ; 146(3): EL258, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31590517

RESUMO

When a feed-forward neural network (FNN) is trained for acoustic source ranging in an ocean waveguide, it is difficult evaluating the FNN ranging accuracy of unlabeled test data. The label is the distance between source and receiver array. A fitting-based early stopping (FEAST) method is introduced to evaluate the FNN ranging error on test data where the distance to the source is unknown. Based on FEAST, when the evaluated ranging error is minimum on test data, training is stopped. This will improve the FNN ranging accuracy on the test data. The FEAST is demonstrated on simulated and experimental data.


Assuntos
Acústica , Redes Neurais de Computação , Som , Algoritmos , Aprendizado de Máquina
20.
J Acoust Soc Am ; 145(6): EL483, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31255152

RESUMO

The received low frequency signals in the long range shallow water will suffer severe attenuation and modal dispersion effect, which will distort the signal and deteriorate the communication performance. In this letter, a modal dispersion compensation receiver is proposed, which exploits the de-dispersion transform to compensate intra-mode dispersion and the rake combination to combine the multi-mode components. With the proposed receiver, the waveform expansion of high order modes is compensated, and thus more modes can be distinguished from the noise and the rake combination gain is improved, which leads to high communication accuracy. Simulation results show that the proposed receiver can achieve about 3 dB gain for the 40 km range and signal with a center frequency 400 Hz.

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