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1.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(2): 231-236, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-33825389

RESUMO

Accurate CT simulation is the key link of precision radiotherapy, and the performance of the localization couch of CT simulator directly affects the accuracy of radiotherapy. With the rapid development of precision radiotherapy, conventional large aperture radiotherapy special CT simulator is difficult to meet the needs of precision radiotherapy localization, so most radiotherapy centers choose high-end diagnostic CT machines equipped with a flat tabletop for radiotherapy localization. In clinical work, the performance testing of the CT simulator localization couch is easy to be ignored. In addition, there are some problems such as insufficient precision in transforming the cradle-shaped couch top of diagnostic CT into a special flat couch top for radiotherapy. This paper provided an in-depth description of the improved design and performance test of the localization couch of the first special GE Revolution CT simulator for radiotherapy introduced by West China Hospital of Sichuan University. After the improvement, all the acceptance tests of the localization couch are in line with the standard, and the performance meets the high-precision radiotherapy localization needs of patients with different body weight in the center.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X , China , Simulação por Computador , Humanos , Imagens de Fantasmas
2.
PLoS Pathog ; 17(3): e1009347, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33647067

RESUMO

In the field, many insect-borne crop viral diseases are more suitable for maintenance and spread in hot-temperature areas, but the mechanism remains poorly understood. The epidemic of a planthopper (Sogatella furcifera)-transmitted rice reovirus (southern rice black-streaked dwarf virus, SRBSDV) is geographically restricted to southern China and northern Vietnam with year-round hot temperatures. Here, we reported that two factors of endoplasmic reticulum-associated degradation (ERAD) machinery, the heat shock protein DnaJB11 and ER membrane protein BAP31, were activated by viral infection to mediate the adaptation of S. furcifera to high temperatures. Infection and transmission efficiencies of SRBSDV by S. furcifera increased with the elevated temperatures. We observed that high temperature (35°C) was beneficial for the assembly of virus-containing tubular structures formed by nonstructural protein P7-1 of SRBSDV, which facilitates efficient viral transmission by S. furcifera. Both DnaJB11 and BAP31 competed to directly bind to the tubule protein P7-1 of SRBSDV; however, DnaJB11 promoted whereas BAP31 inhibited P7-1 tubule assembly at the ER membrane. Furthermore, the binding affinity of DnaJB11 with P7-1 was stronger than that of BAP31 with P7-1. We also revealed that BAP31 negatively regulated DnaJB11 expression through their direct interaction. High temperatures could significantly upregulate DnaJB11 expression but inhibit BAP31 expression, thereby strongly facilitating the assembly of abundant P7-1 tubules. Taken together, we showed that a new temperature-dependent protein quality control pathway in the ERAD machinery has evolved for strong activation of DnaJB11 for benefiting P7-1 tubules assembly to support efficient transmission of SRBSDV in high temperatures. We thus deduced that ERAD machinery has been hitchhiked by insect-borne crop viruses to enhance their transmission in tropical climates.

3.
Head Neck ; 43(6): 1838-1847, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33605501

RESUMO

BACKGROUND: Treatment of nasopharyngeal carcinoma (NPC) is evolving toward Intensity-modulated radiotherapy (IMRT) era, which requires patient-specific reestimation of survival outcomes in modern health care. METHODS: A total of 488 detectable pre-treatment Epstein-Barr virus (EBV) DNA patients (stage II-IVa) treated with induction chemotherapy (IC) and IMRT were examined (training set, n = 325; validation set, n = 163). RESULTS: Concurrent chemotherapy (CC) was still an independent prognosticator for overall survival (OS) and progression-free survival (PFS). Both nomograms included age, T classification, N classification, post-IC EBV DNA, and CC. Predictions correlated well with observed 3-/5-year OS and PFS. The concordance index was 0.776 (95% confidence interval (CI) 0.69-0.86) for OS and 0.742 (95% CI 0.65-0.83) for PFS in the validation cohort. The nomograms can successfully classify patients into low- and high-risk groups. CONCLUSION: The validated nomograms provided useful prediction of OS and PFS for detectable pre-treatment EBV DNA patients with NPC in IMRT era.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33634551

RESUMO

Precise control of the composition and structure of active sites in an atom-by-atom fashion remains insuperable for heterogeneous catalysts. Here, we introduce tailor-made catalytic sites for the cycloaddition of CO2 to epoxides achieved by implementing Ag atoms at different levels of liberation in atomically precise Au nanoclusters. Our results reveal that a single open Ag site on the Au19 Ag4 cluster improves the ring-opening of epoxides and sequent CO2 insertion, while the partially exposed Ag site on the Au20 Ag1 cluster exhibits a weak affinity for epoxides and poor efficiency for CO2 capture. Structural tunability imparted by the atom-by-atom tailoring and unusual atomic charges distributed on Au and Ag atoms of the three clusters seem to be crucial for promoting challenging bond cleavages and formations in the chemical utilization of CO2 .

5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(1): 109-113, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33522189

RESUMO

Clinically, beam matching can greatly improve the flexibility and efficiency of treating patients between different medical electron linacs. However, in addition to the regular quality assurance (QA) test of the machine performance of linacs, there is still a lack of comprehensive evaluation of the clinical radiotherapy performance of beam-matched linacs. In this paper, the performance of volumetric modulated arc therapy (VMAT) between three closely matched linacs was evaluated by statistical process control (SPC) technology. It was found that the average and median γ passing rates of the VMAT QA processes of the three linacs had little difference, but the process capability levels were at three different levels. The results show that SPC technology can effectively evaluate the performance of beam matching for medical electron linacs, improve the patient-specific VMAT QA processes, and guide clinical decision-making.


Assuntos
Elétrons , Aceleradores de Partículas , Garantia da Qualidade dos Cuidados de Saúde , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada
6.
Radiat Oncol ; 16(1): 13, 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446245

RESUMO

BACKGROUND: Surface-guided radiation therapy can be used to continuously monitor a patient's surface motions during radiotherapy by a non-irradiating, noninvasive optical surface imaging technique. In this study, machine learning methods were applied to predict external respiratory motion signals and predict internal liver motion in this therapeutic context. METHODS: Seven groups of interrelated external/internal respiratory liver motion samples lasting from 5 to 6 min collected simultaneously were used as a dataset, Dv. Long short-term memory (LSTM) and support vector regression (SVR) networks were then used to establish external respiratory signal prediction models (LSTMpred/SVRpred) and external/internal respiratory motion correlation models (LSTMcorr/SVRcorr). These external prediction and external/internal correlation models were then combined into an integrated model. Finally, the LSTMcorr model was used to perform five groups of model updating experiments to confirm the necessity of continuously updating the external/internal correlation model. The root-mean-square error (RMSE), mean absolute error (MAE), and maximum absolute error (MAX_AE) were used to evaluate the performance of each model. RESULTS: The models established using the LSTM neural network performed better than those established using the SVR network in the tasks of predicting external respiratory signals for latency-compensation (RMSE < 0.5 mm at a latency of 450 ms) and predicting internal liver motion using external signals (RMSE < 0.6 mm). The prediction errors of the integrated model (RMSE ≤ 1.0 mm) were slightly higher than those of the external prediction and external/internal correlation models. The RMSE/MAE of the fifth model update was approximately ten times smaller than that of the first model update. CONCLUSIONS: The LSTM networks outperform SVR networks at predicting external respiratory signals and internal liver motion because of LSTM's strong ability to deal with time-dependencies. The LSTM-based integrated model performs well at predicting liver motion from external respiratory signals with system latencies of up to 450 ms. It is necessary to update the external/internal correlation model continuously.

7.
Med Dosim ; 46(2): 188-194, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33353791

RESUMO

This study describes a new plan complexity metric for volumetric-modulated arc therapy (VMAT) and evaluates the relationship of this metric with the VMAT dosimetric accuracy. The new modulation complexity score for VMAT (NMCSv) that is based on the aperture shape and multi-leaf collimator (MLC) leaf travel is described. Its performance is evaluated through correlation and receiver operating characteristic (ROC) analyses with patient-specific gamma passing rates using 2 3-dimensional diode arrays. For comparison, the following metrics are evaluated using the same correlation analyses: average field width, average leaf travel, modulation complexity score, and leaf travel modulation complexity score. Spearman's rank correlation analysis is performed to examine any relationships between the complexity metrics and the patient-specific gamma passing rates. ROC curves are used to assess the performance of the plan metrics using a gamma passing rate of 3%/3 mm criterion with a 95% tolerance level. In both the diode arrays, the gamma passing rates (3%/3 mm and 2%/2 mm) for patient-specific dosimetric verification of VMAT plans are moderately or weakly correlated to all the complexity metrics. NMCSv demonstrates the highest correlation with the passing rates (r = 0.652, p < 0.001 for Delta4 and r = 0.499, p < 0.001 for ArcCheck) and the highest area under the curve value (0.809, p < 0.01 for Delta4 and 0.734, p < 0.01 for ArcCheck). While using the Delta4 system, NMCSv exhibits an excellent classification performance with area under the curves of 0.926 (sensitivity: 0.913; specificity: 0.860; p < 0.01) and 0.918 (sensitivity: 0.943; specificity: 0.720; p < 0.01) for rectal and cervical cancer plans, respectively. NMCSv as a novel potential clinical plan complexity metric is moderately correlated with the gamma passing rate. It demonstrates the best performance with respect to distinguishing the dosimetric accuracy of VMAT plans among the evaluated metrics. The classification performance of complexity metrics can be affected by various dosimetry verification devices and treatment sites.

8.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(5): 842-847, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33140608

RESUMO

Patient-specific volumetric modulated arc therapy (VMAT) quality assurance (QA) process is an important component of the implementation process of clinical radiotherapy. The tolerance limit and action limit of discrepancies between the calculated dose and the delivered radiation dose are the key parts of the VMAT QA processes as recognized by the AAPM TG-218 report, however, there is no unified standard for these two values among radiotherapy centers. In this study, based on the operational recommendations given in the AAPM TG-218 report, treatment site-specific tolerance limits and action limits of gamma pass rate in VMAT QA processes when using ArcCHECK for dose verification were established by statistical process control (SPC) methodology. The tolerance limit and action limit were calculated based on the first 25 in-control VMAT QA for each site. The individual control charts were drawn to continuously monitor the VMAT QA process with 287 VMAT plans and analyze the causes of VMAT QA out of control. The tolerance limits for brain, head and neck, abdomen and pelvic VMAT QA processes were 94.56%, 94.68%, 94.34%, and 92.97%, respectively, and the action limits were 93.82%, 92.54%, 93.23%, and 90.29%, respectively. Except for pelvic, the tolerance limits for the brain, head and neck, and abdomen were close to the universal tolerance limit of TG-218 (95%), and the action limits for all sites were higher than the universal action limit of TG-218 (90%). The out-of-control VMAT QAs were detected by the individual control chart, including one case of head and neck, two of the abdomen and two of the pelvic site. Four of them were affected by the setup error, and one was affected by the calibration of ArcCHECK. The results show that the SPC methodology can effectively monitor the IMRT/VMAT QA processes. Setting treatment site-specific tolerance limits is helpful to investigate the cause of out-of-control VMAT QA.

9.
Med Phys ; 47(10): 4694-4702, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32677053

RESUMO

PURPOSE: Applying statistical process control (SPC) to intensity-modulated radiotherapy (IMRT)/volumetric modulated arc therapy (VMAT) patient-specific quality assurance (PSQA) program was recommended by the American Association of Physics in Medicine Task Group 218 report, but a comprehensive analysis of PSQA processes with non-normal distributions is lacking. This study investigates SPC and process capability analysis (PCA) methods for non-normal IMRT/VMAT PSQA processes. METHODS: 1119 VMAT PSQAs were performed on three beam-matched linear accelerators (linacs), using gamma analysis. The Anderson-Darling statistic was used to test normality. The control charts for each PSQA process were obtained using three non-normal-based methods and compared with the conventional Shewhart method. The ability of each PSQA process to produce an output within the specification limit was measured using the C pk index; in this study, the C pk index was calculated using two transformation methods and compared with that calculated using the conventional method. The performances of the three linacs were assessed using SPC and PCA methods. RESULTS: All three PSQA processes were non-normal (P < 0.005). Compared to the non-normal-based SPC and PCA methods, the false alarm rates of the conventional method for linac1, linac2, and linac3 were 0.83%, 3.77%, and 4.95% respectively; the minimum overestimated C pk values were 0.59, 0.87, and 1.49, respectively. The process capabilities of the three beam-matched linacs were at different levels. CONCLUSION: For non-normal VMAT PSQA processes, the conventional SPC and PCA methods increase the false alarm rates and overestimate process capabilities. Instead, non-normal-based SPC and PCA methods are more reliable and accurate in non-normal PSQA processes. Statistical process control and PCA are useful tools for assessing the performance of beam-matched linacs.

10.
Angew Chem Int Ed Engl ; 59(47): 21135-21142, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32729214

RESUMO

The emergence of atomically precise metal nanoclusters with unique electronic structures provides access to currently inaccessible catalytic challenges at the single-electron level. We investigate the catalytic behavior of gold Au25 (SR)18 nanoclusters by monitoring an incoming and outgoing free valence electron of Au 6s1 . Distinct performances are revealed: Au25 (SR)18 - is generated upon donation of an electron to neutral Au25 (SR)18 0 and this is associated with a loss in reactivity, whereas Au25 (SR)18 + is generated from dislodgment of an electron from neutral Au25 (SR)18 0 with a loss in stability. The reactivity diversity of the three Au25 (SR)18 clusters stems from different affinities with reactants and the extent of intramolecular charge migration during the reactions, which are closely associated with the valence occupancies of the clusters varied by one electron. The stability difference in the three clusters is attributed to their different equilibria, which are established between the AuSR dissociation and polymerization influenced by one electron.

11.
Radiat Oncol ; 15(1): 170, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32650819

RESUMO

BACKGROUND: Surface-guided radiation therapy (SGRT) employs a non-invasive real-time optical surface imaging (OSI) technique for patient surface motion monitoring during radiotherapy. The main purpose of this study is to verify the real-time tracking accuracy of SGRT for respiratory motion and provide a fitting method to detect the time delay of gating. METHODS: A respiratory motion phantom was utilized to simulate respiratory motion using 17 cosine breathing pattern curves with various periods and amplitudes. The motion tracking of the phantom was performed by the Catalyst™ system. The tracking accuracy of the system (with period and amplitude variations) was evaluated by analyzing the adjusted coefficient of determination (A_R2) and root mean square error (RMSE). Furthermore, 13 actual respiratory curves, which were categorized into regular and irregular patterns, were selected and then simulated by the phantom. The Fourier transform was applied to the respiratory curves, and tracking accuracy was compared through the quantitative analyses of curve similarity using the Pearson correlation coefficient (PCC). In addition, the time delay of amplitude-based respiratory-gating radiotherapy based on the OSI system with various beam hold times was tested using film dosimetry for the Elekta Versa-HD and Varian Edge linacs. A dose convolution-fitting method was provided to accurately measure the beam-on and beam-off time delays. RESULTS: A_R2 and RMSE for the cosine curves were 0.9990-0.9996 and 0.110-0.241 mm for periods ranging from 1 s to 10 s and 0.9990-0.9994 and 0.059-0.175 mm for amplitudes ranging from 3 mm to 15 mm. The PCC for the actual respiratory curves ranged from 0.9955 to 0.9994, which was not significantly affected by breathing patterns. For gating radiotherapy, the average beam-on and beam-off time delays were 1664 ± 72 and 25 ± 30 ms for Versa-HD and 303 ± 45 and 34 ± 25 ms for Edge, respectively. The time delay was relatively stable as the beam hold time increased. CONCLUSIONS: The OSI technique provides high accuracy for respiratory motion tracking. The proposed dose convolution-fitting method can accurately measure the time delay of respiratory-gating radiotherapy. When the OSI technique is used for respiratory-gating radiotherapy, the time delay for the beam-on is considerably longer than the beam-off.

12.
Herz ; 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32394020

RESUMO

BACKGROUND: This study aimed to investigate the impact of metabolic syndrome (MetS) with microalbuminuria on the improvement of cardiac function after acute myocardial infarction (AMI). METHODS: Nondiabetic patients with acute ST segment elevation MI (STEMI) who underwent coronary revascularization from 2013 to 2017 were included. They were grouped according to history of MetS and microalbuminuria test results as follows: microalbuminuria/MetS group, normoalbuminuria/MetS group, microalbuminuria/no MetS group, and normoalbuminuria/no MetS group. Left ventricular ejection fraction (LVEF) and serum N-terminal pro-brain natriuretic peptide (NT-proBNP) levels at the 6­month follow-up were measured and the predictive value of MetS with microalbuminuria on recovery of cardiac function was assessed by multivariable logistic regression modeling. RESULTS: A total of 530 STEMI patients were included (average age = 66.6 years). Analysis of covariance showed that LVEF recovery in the normoalbuminuria/no MetS group was better than that of the normoalbuminuria/MetS, microalbuminuria/no MetS, and microalbuminuria/MetS groups (49.22% vs. 48.92% vs. 47.48% vs. 46.99%, respectively, p < 0.001) when acute phase LVEF was the covariable. The NT-proBNP level of the normoalbuminuria/no MetS group at the 6­month follow-up was lower than that of the microalbuminuria/MetS group (p < 0.001). Further regression analysis revealed that there was a lower probability of complete cardiac function recovery after 6 months in patients with microalbuminuria (odds ratio: 0.455) than in patients without microalbuminuria (95% CI: 0.316-0.655, p < 0.001). CONCLUSION: Although post-AMI cardiac function in MetS patients with microalbuminuria can be improved after revascularization, the improvement is not as good as that of patients without microalbuminuria, suggesting that clinical attention should be paid to this subgroup.

13.
J Musculoskelet Neuronal Interact ; 20(1): 142-148, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32131379

RESUMO

OBJECTIVE: to investigate the combined construction of injectable tissue-engineered bone with calcium phosphate bone cement composite (CPC) and bone marrow mesenchymal stem cells (BMMSCs). METHODS: The proliferation activity of BMMSCs encapsulated was detected by CCK8 method on the 7th day after its self-coagulation by CPC. qRT-PCR was used to detect the expressions of mRNA. The microcapsules of BMMSCs combined with CPC were completely filled in the defect site in the experimental group, and the control group not filled. The two groups were sutured and routinely reared, double upper limb X-ray examination performed after operation. RESULTS: Those of two groups were on the rise over time, which were higher at the 1st, 3rd, 5th and 7th days than those at the previous time points (all P<0.05). The relative expressions of ALP and CALCR at the 7th day were higher than those at the day in BMMSCs combined with the CPC group and BMMSCs group (all P<0.05). The relative expression of CALCR was significantly higher in BMMSCs combined with the CPC group than that in the BMMSCs group on the 7th day (P<0.05). CONCLUSION: With good cell activity and biological activity, the combined construction of the tissue-engineered bone with BMMSCs and CPC can be used as an ideal treatment material for bone tissue repair and connection.

14.
Biol Res ; 52(1): 61, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31870440

RESUMO

BACKGROUND: Papillary thyroid cancer (PTC) is the most common malignancy of all thyroid cancers. LncRNA LINC00460 has been proved to play roles in the oncogenesis and progression of various tumors, including papillary thyroid cancer. However, the potential molecular mechanism of LINC00460 in PTC is poorly investigated. RESULTS: LINC00460 was upregulated in PTC tissues and cells. Raf1 was upregulated in PTC tissues, but miR-485-5p was down-regulated. High LINC00460 expression was associated with poor prognosis. LINC00460 knockdown suppressed proliferation, migration, invation and EMT of PTC cells. Bioinformatics prediction revealed that LINC00460 had binding sites with miR-485-5p, which was validated by luciferase reporter assay. In addition, miR-485-5p was confirmed to directly target Raf1 3'-UTR. Moreover, LINC00460 promoted PTC progression by sponging miR-485-5p to elevate the expression of Raf1. Knockdown of LINC00460 restrained tumor growth in vivo. CONCLUSION: LINC00460 induced proliferation, migration, invation and EMT of PTC cells by regulating the LINC00460/miR-485-5p/Raf1 axis, which indicated that LINC00460 may be a potential biomarker and therapeutic target for PTC.


Assuntos
MicroRNAs/genética , RNA Longo não Codificante/genética , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Apoptose , Proliferação de Células , Transformação Celular Neoplásica , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Regulação para Cima
15.
Zhongguo Yi Liao Qi Xie Za Zhi ; 43(5): 326-329, 2019 Sep 30.
Artigo em Chinês | MEDLINE | ID: mdl-31625327

RESUMO

MRI simulation images quality of head and neck coil scanning is better than that of radiotherapy surface coil, but currently the head and neck coil is not compatible with radiotherapy positioning devices. In this paper, a new fixation device is developed based on computer reverse engineering technology, which can be used in combination with head and neck coil. This article focuses on discussing the feasibility of the new device in radiotherapy. The obtained ACR phantom and Cat phantom 504 images were used to analyze MR and CT images quality assurance indicators. The dose attenuation of 6 MV photons was measured using the ionization chamber. The results showed each index met the clinical application requirements of intracranial tumor radiotherapy, thereby it can be used in intracranial tumor radiotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço , Imagem por Ressonância Magnética , Estudos de Viabilidade , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética/instrumentação , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador
16.
Oral Oncol ; 98: 85-91, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31569054

RESUMO

OBJECTIVES: To develop a multidimensional nomogram for predicting the progression-free survival (PFS) in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) (stage III-IVa). MATERIALS AND METHODS: A total of 224 patients with locoregionally advanced NPC (training cohort, n = 149; validation cohort, n = 75) were retrospectively included. We extracted 260 radiomic features from the primary tumor and lymph nodes on the axial contrast-enhanced T1 weighted and T2 weighted MRI. Radiomic signatures of the gross tumor volume (RSnx) and lymph node (RSnd), Dose Volume Histogram (DVH) signature reflecting planning score (PS), and clinical characteristics were included as potential predictors of PFS. The least absolute shrinkage and selection operator (LASSO) regression were applied for feature selection and data dimension reduction. A nomogram was developed by incorporating the selected predictors. The C-index and calibration curve were used to assess discrimination and calibration power of the nomogram, respectively. RESULTS: RSnd, PS, and tumor-node-metastasis (TNM) stage were the independent predictors for PFS (all p < 0.05). The nomogram integrating the three factors achieved a C-index of 0.811 (95% CI: 0.74-0.882) in the validation cohort for predicting PFS, which outperformed than that of the TNM stage alone (C-index, 0.613, 95% CI: 0.532-0.694). Subgroup analysis showed Epstein-Barr virus (EBV) DNA status improved the predictive accuracy of the nomogram (C-index, 0.86, 95% CI: 0.787-0.933). CONCLUSIONS: The multidimensional nomogram incorporating RSnd, PS, and TNM stage showed high performance for predicting PFS in patients with locoregionally advanced NPC.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/mortalidade , Estadiamento de Neoplasias/métodos , Nomogramas , Adulto , Terapia Combinada , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Metástase Linfática , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/terapia , Prognóstico , Intervalo Livre de Progressão , Curva ROC
17.
Chaos ; 29(5): 053117, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31154760

RESUMO

Recovering network topologies is of great significance in the study of complex networks. In this paper, a method for identifying structures of multilayer networks is proposed via compressive sensing and Taylor expansion. By using this method, the topologies of multilayer networks with unknown node dynamical functions can be identified from a relatively small number of observations. Numerical experiments are provided to show the effectiveness and efficiency of the method on different types of multilayer networks, where the intralayer topology and the interlayer topology of a multilayer network can be identified simultaneously. In particular, the topology of one layer can be identified even when nodes of the other layer are unobservable.

18.
Environ Technol ; 40(7): 807-812, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29185884

RESUMO

This work aimed to investigate the effectiveness of ozone in degradation of polyoxymethylene (POM) effluent in a rotating packed bed (RPB) (O3-RPB system). The degradation efficiency was evaluated in terms of chemical oxygen demand (COD), 5-day biological oxygen demand (BOD5) and BOD5/COD under various operating conditions. Pilot experiments comprising the O3-RPB unit coupled with a biological contact oxidation unit were also carried out. The COD removal rates in the pilot process increased markedly to about 70-85% compared to about 40% in the original treatment process, which is the tertiary aerobic treatment in the plant, confirming that the O3-RPB system is very efficient in improving the biodegradability of the POM effluent.


Assuntos
Ozônio , Purificação da Água , Análise da Demanda Biológica de Oxigênio , Oxirredução , Resinas Sintéticas , Eliminação de Resíduos Líquidos
19.
Med Dosim ; 44(2): 107-110, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29678482

RESUMO

The eye lens is recognized as one of the most radiosensitive structures in the human body. The widespread use of intensity-modulated radiotherapy (IMRT) complicates dose verification and necessitates high standards of dose computation. The purpose of this work was to assess the computed dose accuracy of eye lens through measurements using a metal-oxide-semiconductor field-effect transistor (MOSFET) dosimetry system. Sixteen clinical IMRT plans of head and neck patients were copied to an anthropomorphic head phantom. Measurements were performed using the MOSFET dosimetry system based on the head phantom. Two MOSFET detectors were imbedded in the eyes of the head phantom as the left and the right lens, covered by approximately 5-mm-thick paraffin wax. The measurement results were compared with the calculated values with a dose grid size of 1 mm. Sixteen IMRT plans were delivered, and 32 measured lens doses were obtained for analysis. The MOSFET dosimetry system can be used to verify the lens dose, and our measurements showed that the treatment planning system used in our clinic can provide adequate dose assessment in eye lenses. The average discrepancy between measurement and calculation was 6.7 ± 3.4%, and the largest discrepancy was 14.3%, which met the acceptability criterion set by the American Association of Physicists in Medicine Task Group 53 for external beam calculation for multileaf collimator-shaped fields in buildup regions.


Assuntos
Cristalino/efeitos da radiação , Radiometria , Radioterapia de Intensidade Modulada , Humanos , Imagens de Fantasmas , Dosagem Radioterapêutica , Reprodutibilidade dos Testes
20.
Biol. Res ; 52: 61, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1100913

RESUMO

BACKGROUND: Papillary thyroid cancer (PTC) is the most common malignancy of all thyroid cancers. LncRNA LINC00460 has been proved to play roles in the oncogenesis and progression of various tumors, including papillary thyroid cancer. However, the potential molecular mechanism of LINC00460 in PTC is poorly investigated. RESULTS: LINC00460 was upregulated in PTC tissues and cells. Raf1 was upregulated in PTC tissues, but miR-485-5p was down-regulated. High LINC00460 expression was associated with poor prognosis. LINC00460 knockdown suppressed proliferation, migration, invation and EMT of PTC cells. Bioinformatics prediction revealed that LINC00460 had binding sites with miR-485-5p, which was validated by luciferase reporter assay. In addition, miR-485-5p was confirmed to directly target Raf1 3'-UTR. Moreover, LINC00460 promoted PTC progression by sponging miR-485-5p to elevate the expression of Raf1. Knockdown of LINC00460 restrained tumor growth in vivo. CONCLUSION: LINC00460 induced proliferation, migration, invation and EMT of PTC cells by regulating the LINC00460/miR-485-5p/Raf1 axis, which indicated that LINC00460 may be a potential biomarker and therapeutic target for PTC.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade
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