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1.
Cancers (Basel) ; 16(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39001379

RESUMO

The ability to predict or detect colorectal cancer (CRC) recurrence early after surgery enables physicians to apply appropriate treatment plans and different follow-up strategies to improve patient survival. Overall, 30-50% of CRC patients experience cancer recurrence after radical surgery, but current surveillance tools have limitations in the precise and early detection of cancer recurrence. Circulating tumor cells (CTCs) are cancer cells that detach from the primary tumor and enter the bloodstream. These can provide real-time information on disease status. CTCs might become novel markers for predicting CRC recurrence and, more importantly, for making decisions about additional adjuvant chemotherapy. In this review, the clinical application of CTCs as a therapeutic marker for stage II CRC is described. It then discusses the utility of CTCs for monitoring cancer recurrence in advanced rectal cancer patients who undergo neoadjuvant chemoradiotherapy. Finally, it discusses the roles of CTC subtypes and CTCs combined with clinicopathological factors in establishing a multimarker model for predicting CRC recurrence.

2.
Int Ophthalmol ; 44(1): 213, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700596

RESUMO

PURPOSE: This study aimed to explore the diagnostic value of whole-orbit-based multiparametric assessment on Dixon MRI for the evaluation of the thyroid eye disease (TED) activity. METHODS: The retrospective study enrolled patients diagnosed as TED and obtained their axial and coronal Dixon MRI scans. Multiparameters were assessed, including water fraction (WF), fat fraction (FF) of extraocular muscles (EOMs), orbital fat (OF), and lacrimal gland (LG). The thickness of OF and herniation of LG were also measured. Univariable and multivariable logistic regression was applied to construct prediction models based on single or multiple structures. Receiver operating characteristic (ROC) curve analysis was also implemented. RESULTS: Univariable logistic analysis revealed significant differences in water fraction (WF) of the superior rectus (P = 0.018), fat fraction (FF) of the medial rectus (P = 0.029), WF of OF (P = 0.004), and herniation of LG (P = 0.012) between the active and inactive TED phases. Multivariable logistic analysis and corresponding receiver operating characteristic curve (ROC) analysis of each structure attained the area under the curve (AUC) values of 0.774, 0.771, and 0.729 for EOMs, OF, and LG, respectively, while the combination of the four imaging parameters generated a final AUC of 0.909. CONCLUSIONS: Dixon MRI may be used for fine multiparametric assessment of multiple orbital structures. The whole-orbit-based model improves the diagnostic performance of TED activity evaluation.


Assuntos
Oftalmopatia de Graves , Músculos Oculomotores , Órbita , Curva ROC , Humanos , Masculino , Feminino , Oftalmopatia de Graves/diagnóstico , Oftalmopatia de Graves/diagnóstico por imagem , Estudos Retrospectivos , Pessoa de Meia-Idade , Órbita/diagnóstico por imagem , Órbita/patologia , Músculos Oculomotores/diagnóstico por imagem , Músculos Oculomotores/patologia , Adulto , Idoso , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Imageamento por Ressonância Magnética/métodos , Aparelho Lacrimal/diagnóstico por imagem , Aparelho Lacrimal/patologia
3.
Sensors (Basel) ; 24(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38610363

RESUMO

Film cooling technology is of great significance to enhance the performance of aero-engines and extend service life. With the increasing requirements for film cooling efficiency, researchers and engineers have carried out a lot of work on the precision and digital measurement of cooling holes. Based on the above, this paper outlines the importance and principles of film cooling technology and reviews the evolution of cooling holes. Also, this paper details the traditional measurement methods of the cooling hole used in current engineering scenarios with their limitations and categorizes digital measurement methods into five main types, including probing measurement technology, optical measurement technology, infrared imaging technology, computer tomography (CT) scanning technology, and composite measurement technology. The five types of methods and integrated automated measurement platforms are also analyzed. Finally, through a generalize and analysis of cooling hole measurement methods, this paper points out technical challenges and future trends, providing a reference and guidance for forward researches.

4.
Sensors (Basel) ; 24(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38544029

RESUMO

In this article, we propose and demonstrate a probe-type multi-core fiber (MCF) sensor for the multi-parameter measurement of seawater. The sensor comprises an MCF and two capillary optical fibers (COFs) with distinct inner diameters, in which a 45° symmetric core reflection (SCR) structure and a step-like inner diameter capillary (SIDC) structure filled with polydimethylsiloxane (PDMS) are fabricated at the fiber end. The sensor is equipped with three channels for different measurements. The surface plasmon resonance (SPR) channel (CHSPR) based on the side-polished MCF is utilized for salinity measurement. The fiber end air cavity, forming the Fabry-Pérot interference (FPI) channel (CHFPI), is utilized for pressure and temperature measurement. Additionally, the fiber Bragg grating (FBG) channel (CHFBG), which is inscribed in the central core, serves as temperature compensation for the measurement results. By combining three sensing principles with space division multiplexing (SDM) technology, the sensor overcomes the common challenges faced by multi-parameter sensors, such as channel crosstalk and signal demodulation difficulties. The experimental results indicate that the sensor has sensitivities of 0.36 nm/‱, -10.62 nm/MPa, and -0.19 nm/°C for salinity, pressure, and temperature, respectively. As a highly integrated and easily demodulated probe-type optical fiber sensor, it can serve as a valuable reference for the development of multi-parameter fiber optic sensors.

5.
Small ; 20(7): e2303962, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37789502

RESUMO

Previous on-chip technologies for characterizing the cellular mechanical properties often suffer from a low throughput and limited sensitivity. Herein, an inertial multi-force deformability cytometry (IMFDC) is developed for high-throughput, high-accuracy, and high-applicability tumor cell mechanotyping. Three different deformations, including shear deformations and stretch deformations under different forces, are integrated with the IMFDC. The 3D inertial focusing of cells enables the cells to deform by an identical fluid flow, and 10 parameters, such as cell area, perimeter, deformability, roundness, and rectangle deformability, are obtained in three deformations. The IMFDC is able to evaluate the deformability of different cells that are sensitive to different forces on a single chip, demonstrating the high applicability of the IMFDC in analyzing different cell lines. In identifying cell types, the three deformations exhibit different mechanical responses to cells with different sizes and deformability. A discrimination accuracy of ≈93% for both MDA-MB-231 and MCF-10A cells and a throughput of ≈500 cells s-1 can be achieved using the multiple-parameters-based machine learning model. Finally, the mechanical properties of metastatic tumor cells in pleural and peritoneal effusions are characterized, enabling the practical application of the IMFDC in clinical cancer diagnosis.


Assuntos
Técnicas Analíticas Microfluídicas , Neoplasias , Humanos , Fenômenos Mecânicos , Citometria de Fluxo
6.
Quant Imaging Med Surg ; 13(8): 4879-4896, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37581036

RESUMO

Background: Estimation of the global optima of multiple model parameters is valuable for precisely extracting parameters that characterize a physical environment. This is especially useful for imaging purposes, to form reliable, meaningful physical images with good reproducibility. However, it is challenging to avoid different local minima when the objective function is nonconvex. The problem of global searching of multiple parameters was formulated to be a k-D move in the parameter space and the parameter updating scheme was converted to be a state-action decision-making problem. Methods: We proposed a novel Deep Q-learning of Model Parameters (DQMP) method for global optimization which updated the parameter configurations through actions that maximized the Q-value and employed a Deep Reward Network (DRN) designed to learn global reward values from both visible fitting errors and hidden parameter errors. The DRN was constructed with Long Short-Term Memory (LSTM) layers followed by fully connected layers and a rectified linear unit (ReLU) nonlinearity. The depth of the DRN depended on the number of parameters. Through DQMP, the k-D parameter search in each step resembled the decision-making of action selections from 3k configurations in a k-D board game. Results: The DQMP method was evaluated by widely used general functions that can express a variety of experimental data and further validated on imaging applications. The convergence of the proposed DRN was evaluated, which showed that the loss values of six general functions all converged after 12 epochs. The parameters estimated by the DQMP method had relative errors of less than 4% for all cases, whereas the relative errors achieved by Q-learning (QL) and the Least Squares Method (LSM) were 17% and 21%, respectively. Furthermore, the imaging experiments demonstrated that the imaging of the parameters estimated by the proposed DQMP method were the closest to the ground truth simulation images when compared to other methods. Conclusions: The proposed DQMP method was able to achieve global optima, thus yielding accurate model parameter estimates. DQMP is promising for estimating multiple high-dimensional parameters and can be generalized to global optimization for many other complex nonconvex functions and imaging of physical parameters.

7.
Comput Biol Med ; 159: 106842, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37062254

RESUMO

OBJECTIVE: Hemolysis performance is a crucial criterion for roller pumps utilized in life supporting system. In this study, the factor of hemolysis for roller pumps was selected as the target, and an estimation formulation was built to evaluate its hemolysis. METHODS: Several models were proposed and then simulated with the assistant of Computational fluid dynamics (CFD) framework. The hemolysis performance was calculated using the power law model based on CFD and the estimation model in accordance with geometry parameters proposed in this study. The results of the in vitro experiments were compared with the simulation results. Power law model with the lowest error was utilized in following analysis. RESULTS: As indicated by the simulation result, the rotary speed most significantly affected the hemolysis performance of roller blood pumps, followed by roller number and diameter of tube. The index of hemolysis (IH) for roller blood pumps at a rotary speed of 20-100 rpm ranged from 8.73E-7 to 8.07E-5. The relative error of the estimation model (4.93%) was lower than of the power law model (6.78%). CONCLUSION: The IH led by pumps shows a significant, nonlinear relationship with the rotary speed. The design of multiple rollers design is harmful for hemolysis performance and larger diameter of tube exhibits decreased hemolysis at constant flow rate. An estimation formula was proposed with lower relative error for roller pump with the same shell set, which exhibited reduced computation and elevated convenience. And it can be utilized in hemolysis estimation of roller pumps potentially.


Assuntos
Coração Auxiliar , Hemólise , Humanos , Desenho de Equipamento , Hidrodinâmica
8.
Materials (Basel) ; 16(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36984211

RESUMO

Understanding the brittle fracture behavior of rock is crucial for engineering and Earth science. In this paper, based on acoustic emission (AE) and laser Doppler vibration (LDV) monitoring technology, the staged damage behaviors of rock-like materials with different brittleness degrees under uniaxial compression are studied via multiple parameters. The results show that the brittleness degree determines the fracture mode. As the specimen's brittleness degree increases, the tensile failure increases and shear failure decreases. AE activity is enhanced at the crack damage point. With an increasing specimen brittleness degree, different instability precursor information is shown during the unstable crack growth stage: the AE b value changes from the fluctuating to continuously decreasing state, and the natural frequency changes from the stable fluctuation to upward fluctuation state. The AE b value near the stress drop is the smallest, and it decreases with an increasing brittleness degree. The natural frequency reduction indicates the rock-like fracture. The natural frequency is a symbolic index that reflects staged damage characteristics and predicts the amount of energy released by brittle failure. These findings provide guidelines for rock stability monitoring and provide support for better responses to stability evaluations of rock slopes, rock collapses, and tunnel surrounding rock in engineering.

9.
Echocardiography ; 39(2): 223-232, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35034377

RESUMO

AIMS: This study aimed to explore the validation and the diagnostic value of multiple right ventricle (RV) volumes and functional parameters derived from a novel artificial intelligence (AI)-based three-dimensional echocardiography (3DE) algorithm compared to cardiac magnetic resonance (CMR). METHODS AND RESULTS: A total of 51 patients with a broad spectrum of clinical diagnoses were finally included in this study. AI-based RV 3DE was performed in a single-beat HeartModel mode within 24 hours after CMR. In the entire population, RV volumes and right ventricular ejection fraction (RVEF) measured by AI-based 3DE showed statistically significant correlations with the corresponding CMR analysis (p < 0.05 for all). However, the Bland-Altman plots indicated that these parameters were slightly underestimated by AI-based 3DE. Based on CMR derived RVEF < 45% as RV dysfunction, end-systolic volume (ESV), end-systolic volume index (ESVi), stroke volume (SV), and RVEF showed great diagnostic performance in identifying RV dysfunction, as well as some non-volumetric parameters, including tricuspid annular systolic excursion (TAPSE), fractional area change (FAC), and free-wall longitudinal strains (LS) (p < 0.05 for all). The cutoff value was 43% for RVEF with a sensitivity of 94% and specificity of 67%. CONCLUSION: AI-based 3DE could provide rapid and accurate quantitation of the RV volumes and function with multiple parameters. Both volumetric and non-volumetric measurements derived from AI-based 3DE contributed to the identification of the RV dysfunction.


Assuntos
Ecocardiografia Tridimensional , Disfunção Ventricular Direita , Inteligência Artificial , Ecocardiografia Tridimensional/métodos , Ventrículos do Coração/diagnóstico por imagem , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Reprodutibilidade dos Testes , Volume Sistólico , Função Ventricular Direita
10.
ACS Sens ; 5(1): 171-179, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31885255

RESUMO

The assessment of the petroleum product quality often involves multiple indicators, among which water content and acid value are two major parameters. The complexity of an oil sample and the narrow space in pipeline transport make it difficult to monitor the oil quality in real-time. Considering the practical requirements, a new type of flexible microstrip sensor is proposed in this work. The shape and line width of the microstrip sensor are studied and optimized by theory and experiments. The proposed square spiral-based microstrip sensor has good water content detection resolution at high frequencies with less acid interference, and it can determine the acid value in the low-frequency band. The sensor surface is further passivated, protecting it from direct contact with the oil sample to enhance the electrochemical robustness, and still achieves good detection linearity and high sensitivity. After encapsulation on a flexible substrate, the proposed microstrip sensor realized the non-contact determination of the water content and acid value of oil at the same time, which is only a few millimeters in size and can conform to various tubing wall shapes. Due to the fact that the manufacture of the sensor is CMOS-compatible, we expect it to be readily applied to many other miniaturized chemical-sensing applications.


Assuntos
Técnicas Biossensoriais/métodos , Monitorização Fisiológica/métodos , Indústria de Petróleo e Gás/métodos , Água/química , Contaminação de Equipamentos
11.
Genet Epidemiol ; 43(1): 82-101, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30353568

RESUMO

Commonly in biomedical research, studies collect data in which an outcome measure contains informative excess zeros; for example, when observing the burden of neuritic plaques (NPs) in brain pathology studies, those who show none contribute to our understanding of neurodegenerative disease. The outcome may be characterized by a mixture distribution with one component being the "structural zero" and the other component being a Poisson distribution. We propose a novel variance components score test of genetic association between a set of genetic markers and a zero-inflated count outcome from a mixture distribution. This test shares advantageous properties with single-nucleotide polymorphism (SNP)-set tests which have been previously devised for standard continuous or binary outcomes, such as the sequence kernel association test. In particular, our method has superior statistical power compared to competing methods, especially when there is correlation within the group of markers, and when the SNPs are associated with both the mixing proportion and the rate of the Poisson distribution. We apply the method to Alzheimer's data from the Rush University Religious Orders Study and Memory and Aging Project, where as proof of principle we find highly significant associations with the APOE gene, in both the "structural zero" and "count" parameters, when applied to a zero-inflated NPs count outcome.


Assuntos
Estudos de Associação Genética , Simulação por Computador , Haplótipos/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética
12.
BMC Musculoskelet Disord ; 18(1): 50, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28137249

RESUMO

BACKGROUND: Acetabular dysplasia (AD) is a well-known cause of osteoarthritis (OA) of the hip, with its prevalence previously determined on plain radiography. The prevalence of preexisting AD was reported as 7.3% in a patient-based Asian population. Although computed tomography (CT) could evaluate AD in multiple planes, its prevalence using multiplanar CT images has not been reported. We investigated its prevalence with CT on coronal, axial, and sagittal planes and then determined if adding the axial and sagittal planes enhanced the investigation. METHODS: We retrospectively examined 52 consecutive Japanese individuals (mean age 59.4 years) who had undergone CT for conditions unrelated to hip disorders. The inclusion criteria of CT images were (1) reconstructed axial slice thickness of ≤1 mm and (2) normal pelvic rotations and tilt. Exclusion criteria were (1) age <20 years, (2) neither hip center could be clearly detected, (3) evidence of hip OA. The parameters used to define AD on the coronal plane were the center-edge angle, Sharp angle, acetabular index, acetabular depth ratio, and acetabulum head index. The anterior and posterior acetabular sector angles were used as axial parameters and the vertical-center-anterior margin angle as the sagittal parameter. AD prevalence was calculated using multiplanar images and then compared with the previously reported Asian prevalence using 95% confidence intervals (CI). In this study, we defined "prevalence" as the proportion of subjects who had AD in at least one hip. RESULTS: The mean prevalence of AD on coronal, axial, and sagittal planes was 16.9, 15.4, and 7.7%, respectively. The lowest prevalence found by combining the three planes was 25.0% (95% CI 15.2-38.2%). This prevalence was significantly higher than that in the previously reported Asian population (7.3%). CONCLUSIONS: At the lowest estimate, the prevalence of AD evaluated in three planes was more than twice as high as the previously reported prevalence in Asians when we investigated its prevalence using multiplanar images. The prevalence of AD in the axial and sagittal planes was not negligible. We therefore suggest that it is important to add axial and sagittal planes' data when investigating the prevalence of AD.


Assuntos
Acetábulo/diagnóstico por imagem , Povo Asiático , Luxação do Quadril/diagnóstico por imagem , Luxação do Quadril/epidemiologia , Tomografia Computadorizada por Raios X/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos
13.
Artigo em Inglês | MEDLINE | ID: mdl-27542714

RESUMO

Many studies have investigated exposure biomarkers for high dose radiation. However, no systematic study on which biomarkers can be used in dose estimation through premature chromosome condensation (PCC) analysis has been conducted. The present study aims to screen the high-dose radiation exposure indicator in calyculin A-induced PCC. The dose response of multiple biological endpoints, including G2/A-PCC (G2/M and M/A-PCC) index, PCC ring (PCC-R), ratio of the longest/shortest length (L/L ratio), and length and width ratio of the longest chromosome (L/B ratio), were investigated in calyculin A-induced G2/A-PCC spreads in human peripheral blood lymphocytes exposed to 0-20Gy (dose-rate of 1Gy/min) cobalt-60 gamma-rays. The G2/A-PCC index was decreased with enhanced absorbed doses of 4-20Gy gamma-rays. The G2/A PCC-R at 0-12Gy gamma-rays conformed to Poisson distribution. Three types of PCC-R were scored according to their shape and their solidity or hollowness. The frequencies of hollow PCC-R and PCC-R including or excluding solid ring in G2/A-PCC spreads were enhanced with increased doses. The length and width of the longest chromosome, as well as the length of the shortest chromosome in each G2/M-PCC or M/A-PCC spread, were measured. All L/L or L/B ratios in G2/M-PCC or M/A-PCC spread increased with enhanced doses. A blind test with two new irradiated doses was conducted to validate which biomarker could be used in dose estimation. Results showed that hollow PCC-R and PCC-R including solid ring can be utilized for accurate dose estimation, and that hollow PCC-R was optimal for practical application.


Assuntos
Carcinógenos/toxicidade , Cromossomos/efeitos dos fármacos , Raios gama/efeitos adversos , Linfócitos/efeitos da radiação , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Oxazóis/toxicidade , Adulto , Células Cultivadas , Cromossomos/efeitos da radiação , Radioisótopos de Cobalto , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Humanos , Linfócitos/efeitos dos fármacos , Masculino , Toxinas Marinhas , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos
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