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1.
BMC Cancer ; 23(1): 988, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848844

RESUMO

BACKGROUND: The machine learning models with dose factors and the deep learning models with dose distribution matrix have been used to building lung toxics models for radiotherapy and achieve promising results. However, few studies have integrated clinical features into deep learning models. This study aimed to explore the role of three-dimension dose distribution and clinical features in predicting radiation pneumonitis (RP) in esophageal cancer patients after radiotherapy and designed a new hybrid deep learning network to predict the incidence of RP. METHODS: A total of 105 esophageal cancer patients previously treated with radiotherapy were enrolled in this study. The three-dimension (3D) dose distributions within the lung were extracted from the treatment planning system, converted into 3D matrixes and used as inputs to predict RP with ResNet. In total, 15 clinical factors were normalized and converted into one-dimension (1D) matrixes. A new prediction model (HybridNet) was then built based on a hybrid deep learning network, which combined 3D ResNet18 and 1D convolution layers. Machine learning-based prediction models, which use the traditional dosiomic factors with and without the clinical factors as inputs, were also constructed and their predictive performance compared with that of HybridNet using tenfold cross validation. Accuracy and area under the receiver operator characteristic curve (AUC) were used to evaluate the model effect. DeLong test was used to compare the prediction results of the models. RESULTS: The deep learning-based model achieved superior prediction results compared with machine learning-based models. ResNet performed best in the group that only considered dose factors (accuracy, 0.78 ± 0.05; AUC, 0.82 ± 0.25), whereas HybridNet performed best in the group that considered both dose factors and clinical factors (accuracy, 0.85 ± 0.13; AUC, 0.91 ± 0.09). HybridNet had higher accuracy than that of Resnet (p = 0.009). CONCLUSION: Based on prediction results, the proposed HybridNet model could predict RP in esophageal cancer patients after radiotherapy with significantly higher accuracy, suggesting its potential as a useful tool for clinical decision-making. This study demonstrated that the information in dose distribution is worth further exploration, and combining multiple types of features contributes to predict radiotherapy response.


Assuntos
Neoplasias Esofágicas , Pneumonite por Radiação , Humanos , Pneumonite por Radiação/diagnóstico , Pneumonite por Radiação/etiologia , Pulmão , Aprendizado de Máquina , Dosagem Radioterapêutica , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/complicações
2.
Biomed Eng Online ; 20(1): 101, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627279

RESUMO

BACKGROUND: Neural-network methods have been widely used for the prediction of dose distributions in radiotherapy. However, the prediction accuracy of existing methods may be degraded by the problem of dose imbalance. In this work, a new loss function is proposed to alleviate the dose imbalance and achieve more accurate prediction results. The U-Net architecture was employed to build a prediction model. Our study involved a total of 110 patients with left-breast cancer, who were previously treated by volumetric-modulated arc radiotherapy. The patient dataset was divided into training and test subsets of 100 and 10 cases, respectively. We proposed a novel 'sharp loss' function, and a parameter γ was used to adjust the loss properties. The mean square error (MSE) loss and the sharp loss with different γ values were tested and compared using the Wilcoxon signed-rank test. RESULTS: The sharp loss achieved superior dose prediction results compared to those of the MSE loss. The best performance with the MSE loss and the sharp loss was obtained when the parameter γ was set to 100. Specifically, the mean absolute difference values for the planning target volume were 318.87 ± 30.23 for the MSE loss versus 144.15 ± 16.27 for the sharp loss with γ = 100 (p < 0.05). The corresponding values for the ipsilateral lung, the heart, the contralateral lung, and the spinal cord were 278.99 ± 51.68 versus 198.75 ± 61.38 (p < 0.05), 216.99 ± 44.13 versus 144.86 ± 43.98 (p < 0.05), 125.96 ± 66.76 versus 111.86 ± 47.19 (p > 0.05), and 194.30 ± 14.51 versus 168.58 ± 25.97 (p < 0.05), respectively. CONCLUSIONS: The sharp loss function could significantly improve the accuracy of radiotherapy dose prediction.


Assuntos
Neoplasias da Mama , Radioterapia de Intensidade Modulada , Feminino , Humanos , Redes Neurais de Computação , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
3.
Biomed Eng Online ; 19(1): 39, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32471419

RESUMO

BACKGROUND: Radiotherapy treatment planning dose prediction can be used to ensure plan quality and guide automatic plan. One of the dose prediction methods is incorporating historical treatment planning data into algorithms to estimate the dose-volume histogram (DVH) of organ for new patients. Although DVH is used extensively in treatment plan quality and radiotherapy prognosis evaluation, three-dimensional dose distribution can describe the radiation effects more explicitly. The purpose of this retrospective study was to predict the dose distribution of breast cancer radiotherapy by means of deformable registration into atlas images with historical treatment planning data that were considered to achieve expert level. The atlas cohort comprised 20 patients with left-sided breast cancer, previously treated by volumetric-modulated arc radiotherapy. The registration-based prediction technique was applied to 20 patients outside the atlas cohort. This study evaluated and compared three different approaches: registration to the most similar image from a dataset of individual atlas images (SIM), registration to all images from a database of individual atlas images with the average method (WEI_A), and the weighted method (WEI_F). The dose prediction performance of each strategy was quantified using nine metrics, including the region of interest dose error, 80% and 100% prescription area dice similarity coefficients (DSCs), and γ metrics. A Friedman test and a nonparametric exact Wilcoxon signed rank test were performed to compare the differences among groups. The clinical doses of all cases served as the gold standard. RESULTS: The WEI_F method could achieve superior dose prediction results to those of WEI_A. WEI_F outperformed SIM in the organ-at-risk mean absolute difference (MAD). When using the WEI_F method, the MAD values for the ipsilateral lung, heart, and whole lung were 197.9 ± 42.9, 166 ± 55.1, 122.3 ± 25.5, and 55.3 ± 42.2 cGy, respectively. Moreover, SIM exhibited superior prediction in the DSC and γ metrics. When using the SIM method, the means of the 80% and 100% prescription area DSCs, 33γ metric, and 55γ metric were 0.85 ± 0.05, 0.84 ± 0.05, 0.64 ± 0.13, and 0.84 ± 0.10, respectively. The plan target volume and spinal cord MAD when using SIM and WEI were 235.6 ± 158.4 cGy versus 227.4 ± 144.0 cGy ([Formula: see text]) and 61.4 ± 44.9 cGy versus 55.3 ± 42.2 cGy ([Formula: see text]), respectively. CONCLUSIONS: A predicted dose distribution that approximated the clinical plan could be generated using the methods presented in this study.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Doses de Radiação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem , Tomografia Computadorizada por Raios X , Humanos , Processamento de Imagem Assistida por Computador , Dosagem Radioterapêutica
4.
Mar Drugs ; 15(10)2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29039806

RESUMO

The incorporation of brown algae into biopolymer beads or foams for metal sorption has been previously reported. However, the direct use of these biomasses for preparing foams is a new approach. In this study, two kinds of porous foams were prepared by ionotropic gelation using algal biomass (AB, Laminaria digitata) or alginate (as the reference) and applied for Pb(II) sorption. These foams (manufactured as macroporous discs) were packed in filtration holders (simulating fixed-bed column) and the system was operated in either a recirculation or a one-pass mode. Sorption isotherms, uptake kinetics and sorbent reuse were studied in the recirculation mode (analogous to batch system). In the one-pass mode (continuous fixed-bed system), the influence of parameters such as flow rate, feed metal concentration and bed height were investigated on both sorption and desorption. In addition, the effect of Cu(II) on Pb(II) recovery from binary solutions was also studied in terms of both sorption and desorption. Sorption isotherms are well fitted by the Langmuir equation while the pseudo-second order rate equation described well both sorption and desorption kinetic profiles. The study of material regeneration confirms that the reuse of the foams was feasible with a small mass loss, even after 9 cycles. In the one-pass mode, for alginate foams, a slower flow rate led to a smaller saturation volume, while the effect of flow rate was less marked for AB foams. Competitive study suggests that the foams have a preference for Pb(II) over Cu(II) but cannot selectively remove Pb(II) from the binary solution.


Assuntos
Quelantes/química , Filtração/métodos , Laminaria/fisiologia , Chumbo/química , Poluentes Químicos da Água/química , Adsorção , Alginatos/química , Biomassa , Reatores Biológicos , Cobre/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Modelos Químicos , Porosidade
5.
Artigo em Inglês | MEDLINE | ID: mdl-28463536

RESUMO

The objectives of this study were to investigate the competitive sorption behaviors and mechanisms of heavy metals onto ELMB, a novel eucalyptus-leaf-based magnetic biosorbent, and to study the potential application of ELMB in the treatment of actual zinc smelting effluent after a necessary pretreatment process. ELMB and ELMB-metals systems were characterized using several techniques. Competitive sorption of Zn2+ with Pb2+, Cu2+ and Cd2+ onto ELMB was studied by batch experiments and the used sorbent was separated under a magnetic field. The results show that the ELMB can be considered as paramagnetic material with various functional groups on its surface. The presence of Pb2+, Cu2+ and Cd2+ significantly decreases the sorption of Zn2+ in either the binary system or multimetal systems. The order of adsorption preference is Pb2+ > Cu2+ > Cd2+ > Zn2+ in multimetal systems and the sequence of competitive ability to zinc is: Pb2+ > Cu2+ > Cd2+. Non-competitive Langmuir multicomponent isotherm model fits to the adsorption data of Pb2+ and Cu2+ well in aqueous solution. The co-existent Ca2+ and SO42- decrease the removal efficiencies of heavy metals while the presence of Na+ and Cl- shows little effect in the multimetal solution. In the case of actual zinc smelting effluent, "pretreatment + ELMB sorption" is successfully applied to remove heavy metals and the contents of Zn2+ and its associated metals are well below discharge limits.


Assuntos
Eucalyptus/química , Magnetismo , Folhas de Planta/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zinco/análise , Adsorção , Metais Pesados/análise , Modelos Teóricos , Propriedades de Superfície
6.
World J Surg Oncol ; 14: 89, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-27012522

RESUMO

BACKGROUND: Salvage surgery has been recommended as the approach of choice for neck residue or recurrence of nasopharyngeal carcinoma (NPC) after primary radiotherapy (RT). This study aimed to assess the outcome and prognostic factors, options for different surgical methods, and the extent of neck dissection (ND) for patients. METHODS: NPC patients who had undergone RT and received salvage surgery for neck residue or recurrence from January 2001 to December 2011 were retrospectively analyzed. The overall survival (OS) rate was calculated by Kaplan-Meier method, and prognostic factors were determined by log-rank test and Cox regression analysis. RESULTS: In 153 cases, 96 cases have level I dissections. The metastasis rate was 20/153 (13.07%) for level I metastasis and 7/153 (4.58%) for parotid gland cases. The 3- and 5-year OS rate was 57.2 and 40.6%, respectively, and median survival time was 49 months. By univariate analysis, the age, rN staging, size of lymph nodes (LN), extra-capsular spread (ECS), and surgical procedure were significant prognostic factors. By multivariable analysis, the age, rN staging, and size of LN were significant prognostic factors. CONCLUSIONS: Salvage surgery is effective for neck failure of NPC after primary treatment, but patients with age >50 years, stage rN3, or LN >6 cm have poor prognosis.


Assuntos
Neoplasias Nasofaríngeas/cirurgia , Esvaziamento Cervical , Pescoço/cirurgia , Recidiva Local de Neoplasia/cirurgia , Neoplasia Residual/cirurgia , Terapia de Salvação , Adolescente , Adulto , Idoso , Carcinoma , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Pescoço/patologia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Estadiamento de Neoplasias , Neoplasia Residual/patologia , Neoplasia Residual/radioterapia , Prognóstico , Radioterapia , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
7.
Int J Mol Sci ; 17(9)2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27598128

RESUMO

Alginate and algal-biomass (Laminaria digitata) beads were prepared by homogeneous Ca ionotropic gelation. In addition, glutaraldehyde-crosslinked poly (ethyleneimine) (PEI) was incorporated into algal beads. The three sorbents were characterized by scanning electron microscopy (SEM) coupled with energy dispersive X-ray analysis (EDX): the sorption occurs in the whole mass of the sorbents. Sorption experiments were conducted to evaluate the impact of pH, sorption isotherms, and uptake kinetics. A special attention was paid to the effect of drying (air-drying vs. freeze-drying) on the mass transfer properties. For alginate, freeze drying is required for maintaining the porosity of the hydrogel, while for algal-based sorbents the swelling of the material minimizes the impact of the drying procedure. The maximum sorption capacities observed from experiments were 415, 296 and 218 mg Pb g(-1) and 112, 77 and 67 mg Cu g(-1) for alginate, algal and algal/PEI beads respectively. Though the sorption capacities of algal-beads decreased slightly (compared to alginate beads), the greener and cheaper one-pot synthesis of algal beads makes this sorbent more competitive for environmental applications. PEI in algal beads decreases the sorption properties in the case of the sorption of metal cations under selected experimental conditions.


Assuntos
Alginatos/química , Cobre/química , Chumbo/química , Microesferas , Absorção Fisico-Química , Cátions Bivalentes/química , Laminaria/química
8.
World J Surg Oncol ; 13: 1, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25622525

RESUMO

BACKGROUND: Malignant parotid tumors are rare metastases originating from nasopharyngeal carcinoma (NPC). This study aimed to investigate the clinicopathological features and outcome of patients with metastasis of NPC to parotid lymph nodes after surgical therapy. METHODS: We enrolled 14 NPC patients who had metastatic disease to parotid lymph nodes after IMRT. They received surgical treatment by total parotidectomy with neck dissection, superficial parotidectomy with neck dissection, partial parotidectomy with neck dissection, total parotidectomy, or superficial parotidectomy. Their age, gender, histopathology, clinical findings, and treatment outcome were analyzed. RESULTS: After radiotherapy, parotid metastasis represented as uncontrolled disease in three cases and as recurrent disease in 11 cases. All the 14 patients received salvaged surgery successfully. Pathologic findings showed grade 3 in most patients. The follow-up ranged from 11 to 120 months and the overall three- and five-year survival was 49.5% and 37.1%, respectively. CONCLUSIONS: Metastasis to parotid lymph nodes should be examined in NPC patients after IMRT. Resection of the inferior parotid lymph nodes is recommended for patients with cervical metastasis, and superficial or total parotidectomy and adjuvant therapy are recommended for intraparotid lymph node metastasis.


Assuntos
Linfonodos/patologia , Neoplasias Nasofaríngeas/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias Parotídeas/secundário , Adolescente , Adulto , Idoso , Carcinoma , Terapia Combinada , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/terapia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Neoplasias Parotídeas/mortalidade , Neoplasias Parotídeas/terapia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
9.
Chin J Cancer ; 32(6): 342-52, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23114087

RESUMO

Small cell carcinoma of the esophagus (SCCE) is a rare and aggressive malignant tumor with a poor prognosis. The optimal disease staging system and treatment approaches have not yet been defined. This study aimed to evaluate the prediction of different staging systems for prognosis and treatment options of SCCE. We retrospectively accessed the clinicopathologic characteristics, treatment strategy, and prognosis of 76 patients diagnosed with primary SCCE between 2001 and 2011. The 1-, 2-, 3-, and 5-year overall survival rates were 58%, 31%, 19%, and 13%, respectively. Univariate analysis showed that the 2002 American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) classification (P = 0.002), Veterans Administration Lung Study Group (VALSG) stage (P = 0.001), predisposing factors (P < 0.001), T category (P = 0.023), and M category (P < 0.001) were prognostic factors for overall survival. Multivariate analysis showed that the 2002 AJCC TNM stage (P < 0.001) was the only independent prognostic factor for survival. The value of the area under the receiver operator characteristic (ROC) curve (AUC) of the 2002 AJCC TNM staging system was larger than that of VALSG staging system with regard to predicting overall survival (0.774 vs. 0.620). None of the single treatment regimens showed any benefit for survival by Cox regression analysis. Thus, the 2002 AJCC TMN staging system improved the prediction of SCCE prognosis; however, the optimal treatment regimen for SCCE remains unclear.


Assuntos
Carcinoma de Células Pequenas/classificação , Neoplasias Esofágicas/classificação , Estadiamento de Neoplasias/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Pequenas/terapia , Cisplatino/administração & dosagem , Terapia Combinada , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Esofagectomia/métodos , Etoposídeo/administração & dosagem , Feminino , Humanos , Excisão de Linfonodo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Radioterapia de Alta Energia , Estudos Retrospectivos , Sociedades Médicas , Taxa de Sobrevida , Estados Unidos
10.
Environ Sci Pollut Res Int ; 30(35): 84609-84619, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37368212

RESUMO

The recovery of platinum from industrial waste is of critical importance. Usually, the recovery method is to dissolve the solid waste with acid to form a solution where platinum mainly exists in the form of Pt(IV). Therefore, it is urgent to efficiently and selectively adsorb Pt(IV) ions from acid leachates. In this study, a highly efficient adsorbent was developed by grafting of carboxyl and amine groups onto melamine sponge with alginate-Ca and polyethylenimine-glutaraldehyde (ML/ACPG). Combination of SEM, FTIR and XPS showed that the ML/ACPG sponge had a tree structure and the amino, carboxyl and hydroxyl groups were successfully introduced. Maximum adsorption capacity of ML/ACPG sponge reached up to 101.1 mg/L at pH of 1 (optimum initial pH value). The Pt(IV) ions were readily desorbed (within 60-80 min) using 0.1 M HCl + 0.025 M thiourea solution. Desorption efficiency remained higher than 83.3% while adsorption capacity decreased by less than 6.0% after 5 cycles operation. The ML/ACPG sponge was stable in 3 M of HNO3, NaCl after shaking for 72 h at 300 rpm with mass loss less than 2.5%. The mechanism of Pt(IV) adsorption onto ML/ACPG sponge mainly involved coordination by electrostatic attraction and carboxyl groups by protonated amine groups. The above results confirmed that the ML/ACPG sponge has a good practical application potential for Pt(IV) recovery from acid leachates.


Assuntos
Platina , Triazinas , Platina/química , Triazinas/química , Glutaral , Íons , Aminas , Adsorção , Concentração de Íons de Hidrogênio , Cinética
11.
Comput Intell Neurosci ; 2022: 7173421, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35510058

RESUMO

The vibration compensation control of a hovering helicopter rescue simulator mounted on a crane beam is studied in this research. A Stewart platform is used as the motion generator of the helicopter simulation cabin and the vibration compensation device of the beam, simultaneously. This study describes how the dynamic model of the Stewart platform with consideration of the beam vibration is established. To determine the interference of the Stewart platform motion control in the special application of a large component flexible base requiring large-scale movement, a hybrid vibration controller composed of a feed-forward compensation module and a PD (proportional-derivative) feedback control module is designed. The experimental results show that this method can effectively compensate for the beam vibration and improve the accuracy of the motion reproduction of a helicopter simulation cabin.


Assuntos
Aeronaves , Vibração , Simulação por Computador , Movimento (Física) , Movimento
12.
Wideochir Inne Tech Maloinwazyjne ; 17(3): 524-532, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36187058

RESUMO

Introduction: Papillary thyroid cancer (PTC) is one of the most common malignancies involving the endocrine system. Aim: To explore the clinical value of ultrasound-based radiomics for predicting the recurrence of PTC after complete endoscopic resection. Material and methods: The general data of 361 PTC patients were collected. They were randomly assigned to the modeling group (n = 253) and the validation group (n = 108) according to the ratio of 7 : 3. In the modeling group, the PyRadiomics package was applied to extract radiomic features from preoperative ultrasound images, and least absolute shrinkage and selection operator (LASSO) was used to screen and to construct a radiomics score (Rad-score). Independent prognostic predictors were identified using the Cox proportional hazards model, and a nomogram prediction model was constructed by R software. Results: Using the LASSO regression model, 7 radiomic features were screened and then the Rad-score was calculated. Based on the Rad-score, modeling and validation groups were divided into low-, medium- and high-risk groups, and the 10-year recurrence-free survival rates were 94.7% vs. 95.9%, 83.6% vs. 80.0%, and 50.0% vs. 66.6%, respectively (p < 0.001). Multivariate analysis revealed that age, lymph node metastasis and Rad-score were independent predictors for recurrence-free survival (p < 0.05). Conclusions: The ultrasound-based radiomics score can effectively predict the postoperative recurrence-free survival in patients with PTC. The nomogram prediction model is superior to the AJCC staging system in terms of predictive accuracy and consistency.

13.
Am J Transl Res ; 14(11): 7985-7993, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36505297

RESUMO

OBJECTIVE: By comparing the target dose distribution with or without the robust optimization, the dosimetric advantages of robust optimization and flattening filter free (FFF) in radiation therapy for postmastectomy cancer of the left breast was explored when part of the chest wall target was moved out in case of respiratory motion. MATERIALS AND METHODS: This is a retrospective study. The data of 21 postmastectomy patients with cancer of the left breast from 2019 to 2020 were retrospectively collected. The planned target volume (PTV) dose was prescribed 50 Gy/25 fractions and the treatment plans were designed using 6 MV FFF X ray and volumetric modulated arc therapy (VMAT) technology in RayStation treatment planning system (TPS), with and without robust optimization. The movement of the target area of the internal chest wall (0.50 cm) caused by respiratory movement was simulated by moving the isocenter of the beams. RESULTS: When the chest wall target moved outward, the PTV target area D98, D95, D2, conformity index (CI) and homogeneity index (HI) with robust optimization were better than those without robust optimization. The coverage rate of Planned Target Volume-Chest (PTV-T) V50 with robust optimization was significantly higher than that with no-robust optimization (P<0.001). Clinical target volume (CTV) V50 coverage with robust optimization was 14.49% higher than that with no-robust optimization. In terms of organ-at-risk parameters, the average spinal cord dose of the plan with robust optimization was 13.19% lower than that of the plan with no-robust optimization, and the Lung-L V5 of the plan with no-robust optimization was slightly (1.94%) lower than that of the plan with robust optimization. There was no significant difference in machine execution efficiency between the two groups (P>0.05). CONCLUSIONS: Robust optimization could be adopted in the postoperative radiotherapy planning for cancer in the left breast, for it ensures that the target dose coverage and the dose limit of organ-at-risk still meet the clinical requirements under condition of chest wall displacement caused by respiratory movement.

14.
Chemosphere ; 288(Pt 3): 132666, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34710463

RESUMO

Advanced oxidation processes based on sulfate radicals are considered as a promising approach for environmental remediation. In this study, TiO2@MIL-101(Fe) is successfully fabricated by a facile impregnation method and is used for sodium persulfate (SPS) activation. TiO2@MIL-101@SPS combines the advantages of photocatalysis and SPS activation, which shows high removal efficiency for nitrobenzene and methyl orange. In addition, the effect of multiple factors, including light source, SPS amount and catalyst amount, on nitrobenzene degradation have been investigated. Results show that the nitrobenzene degradation efficiency is up to 66.53 % while that of TOC removal is 32.21 % under 4-h visible light irradiation with 30 mg catalyst and 1.6 mM SPS. Moreover, LC-MS have been carried out to study the route of nitrobenzene degradation. Besides, ESR analysis reveals that both ●SO4- and ●OH radicals are generated sustainably under visible light irradiation, and more ●OH radicals can be detected owing to the synergic effect of photocatalysis and SPS activation. Interfacial charge transfer effect provides photoinduced electrons for the Fe3+/Fe2+ cycle in MIL-101(Fe), which boosts the SPS activation process, resulting in high photocatalytic activity.


Assuntos
Estruturas Metalorgânicas , Sulfatos , Compostos de Sódio , Titânio
15.
Sci Prog ; 104(3): 368504211038162, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34519556

RESUMO

Fully convolutional networks were developed for predicting optimal dose distributions for patients with left-sided breast cancer and compared the prediction accuracy between two-dimensional and three-dimensional networks. Sixty cases treated with volumetric modulated arc radiotherapy were analyzed. Among them, 50 cases were randomly chosen to conform the training set, and the remaining 10 were to construct the test set. Two U-Net fully convolutional networks predicted the dose distributions, with two-dimensional and three-dimensional convolution kernels, respectively. Computed tomography images, delineated regions of interest, or their combination were considered as input data. The accuracy of predicted results was evaluated against the clinical dose. Most types of input data retrieved a similar dose to the ground truth for organs at risk (p > 0.05). Overall, the two-dimensional model had higher performance than the three-dimensional model (p < 0.05). Moreover, the two-dimensional region of interest input provided the best prediction results regarding the planning target volume mean percentage difference (2.40 ± 0.18%), heart mean percentage difference (4.28 ± 2.02%), and the gamma index at 80% of the prescription dose are with tolerances of 3 mm and 3% (0.85 ± 0.03), whereas the two-dimensional combined input provided the best prediction regarding ipsilateral lung mean percentage difference (4.16 ± 1.48%), lung mean percentage difference (2.41 ± 0.95%), spinal cord mean percentage difference (0.67 ± 0.40%), and 80% Dice similarity coefficient (0.94 ± 0.01). Statistically, the two-dimensional combined inputs achieved higher prediction accuracy regarding 80% Dice similarity coefficient than the two-dimensional region of interest input (0.94 ± 0.01 vs 0.92 ± 0.01, p < 0.05). The two-dimensional data model retrieves higher performance than its three-dimensional counterpart for dose prediction, especially when using region of interest and combined inputs.


Assuntos
Neoplasias da Mama , Radioterapia de Intensidade Modulada , Neoplasias Unilaterais da Mama , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Feminino , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos
16.
Chemosphere ; 273: 129695, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33524756

RESUMO

Recently, the discharge of flue gas has become a global issue due to the rapid development in industrial and anthropogenic activities. Various dry and wet treatment approaches including conventional and hybrid hybrid wet scrubbing have been employing to combat against these toxic exhaust emissions. However, certain issues i.e., large energy consumption, generation of secondary pollutants, low regeneration of scrubbing liquid and high efficieny are hindering their practical applications on industrial level. Despite this, the hybrid wet scrubbing technique (advanced oxidation, ionic-liquids and solid engineered interface hybrid materials based techniques) is gaining great attention because of its low installation costs, simultaneous removal of multi-air pollutants and low energy requirements. However, the lack of understanding about the basic principles and fundamental requirements are great hurdles for its commercial scale application, which is aim of this review article. This review article highlights the recent developments, minimization of GHG, sustainable improvements for the regeneration of used catalyst via green and electron rich donors. It explains, various hybrid wet scrubbing techniques can perform well under mild condition with possible improvements such as development of stable, heterogeneous catalysts, fast and in-situ regeneration for large scale applications. Finally, it discussed recovery of resources i.e., N2O, NH3 and N2, the key challenges about several competitive side products and loss of catalytic activity over time to treat toxic gases via feasible solutions by hybrid wet scrubbing techniques.


Assuntos
Poluentes Atmosféricos , Dióxido de Enxofre , Poluentes Atmosféricos/análise , Catálise , Oxirredução , Dióxido de Enxofre/análise
17.
Transl Cancer Res ; 9(2): 901-909, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35117435

RESUMO

BACKGROUND: This study aimed to compare three different therapeutic models based on regional control and the outcome of locally advanced squamous cell carcinoma of the head and neck (SCCHN) after induction chemotherapy (ICT). METHODS: One hundred and twenty patients with locally advanced SCCHN were retrospectively reviewed and divided into three groups. Patients in Group A received induction chemotherapy + concurrent chemoradiotherapy (ICT + CCRT). Patients in Group B received induction chemotherapy + radical surgery + adjuvant radiotherapy with or without chemotherapy (ICT + Surgery + RT/CRT). Patients in Group C received induction chemotherapy + planned neck dissection + concurrent chemoradiotherapy (ICT + PND + CCRT). The clinicopathological characteristics, locoregional recurrence (LR), distant metastasis (DM), and overall survival (OS) were compared among them. RESULTS: The median follow-up time was 20 months. In Group A, Group B and Group C, the 3-year OS was 69.7%, 72.9%, and 65.5% respectively. The LR rate was 35.1%, 26.2%, and 42.9%, respectively. The DM rate was 10.5%, 31.0%, and 9.5%, respectively. There were no significant differences in OS and LR among three groups. The DM in Group B was significantly higher than that in Group A (P<0.05), and was probably higher than that in Group C (P=0.06). CONCLUSIONS: Locally advanced SCCHN has a poor prognosis, and the first treatment is critical. Individualized therapeutic regimen based on the response of ICT could be an ideal solution. As cervical metastatic lymph nodes are less sensitive to ICT than primary tumors, PND before radiation therapy might improve the regional control and throat function preservation. A multidisciplinary team (MDT) collaboration is important throughout the treatment process.

18.
J Hazard Mater ; 386: 121637, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31740300

RESUMO

This study synthesizes polyethyleneimine-glutaraldehyde (PEI-GA) resins using different amounts of GA to crosslink with a certain amount of PEI and compares these adsorbents for the adsorption of Cu(II) (cations) and Se(VI) (anions). Moreover, the stability of adsorption affinity of PEI-GA resins stored in open or sealed conditions is also studied. Results show that the amount of GA for PEI crosslinking does not affect the adsorption performance for Se(VI), especially when PEI/GA mass ratio is less than 2, while for Cu(II), the increase on GA amount decreases Cu(II) adsorption capacity. This difference is directly correlated to the change in the adsorption mechanism from electrostatic attraction to chelation. The primary and secondary amine groups on PEI can easily react with CO2 in the air to form carbamate, potentially affecting the adsorption performance of PEI. Results also indicate that the adsorption efficiency for Se(VI) is hardly affected by the storage condition, while that for Cu(II) decreases significantly after 20-day storage compared to the freshly prepared ones. In addition, all of the adsorbents can selectively remove Se(VI) from Se(VI)-As(V) system and Cu(II) from Pb(II)-Cu(II) system, indicating that the crosslinking has no significant influence on the selectivity.

19.
Front Oncol ; 10: 526360, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33552942

RESUMO

BACKGROUND AND OBJECTIVE: Radiotherapy (RT) is the primary treatment option for nasopharyngeal carcinoma (NPC), but it is associated with radiation-induced sarcomas (RISs). This study aims to investigate clinicopathological features and head and neck RIS prognosis after NPC RT. METHODS: The medical and radiological records of the NPC patients (n =14,074) referred to Zhejiang Cancer Hospital, Hang Zhou, China between January 1995 and December 2018 were retrospectively reviewed. Among them, 22 patients were determined to have RIS after RT for NPC. The clinicopathological data, diagnosis, treatment, and follow-up results of 22 patients with RIS were analyzed in this retrospective research. All 22 patients underwent surgery as the main treatment. The levels of Overall Survival (OS) were determined through the Log-rank test and Kaplan-Meier method. RESULTS: Among these patients, 13 were males and nine females with the male/female ratio of 1.44:1. The age during the primary RT of NPC ranged from 25 to 61 years old (median age: 37 years old). Patients' ages ranged from 33 to 73 years old (median age: 52.5 years old) when diagnosed with RIS. The latency period for development of the RIS was between 3 and 36 years (median: 8.5 years) after RT. In this cohort, R0 resection was achieved in 13 cases, R1 resection in five cases, and R2 resection in four cases. During the follow-up period ranged from 2 to 102 months (median 14 months), 15 patients had died of the disease. Kaplan-Meier method showed that the 2-year, 3-year, and the 5-year cumulative OS rate was 50.3, 43.2, and 14.4%, respectively. The median survival time was 34 months. Surgical resection with R0 resection achieves a significantly better prognosis (P = 0.012). Patients under the age of 37 years old at the time of initial RT had a relatively better prognosis (P = 0.035). CONCLUSIONS: Although the incidence of RIS after RT of NPC is generally low, the treatment of RIS is very difficult. The RISs are associated with poor overall prognosis. R0 resection can improve the prognosis thus it should be considered as the primary and optimal choice for the treatment of RIS.

20.
Carbohydr Polym ; 225: 115177, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521319

RESUMO

Highly percolating membranes are prepared by the interaction of polyethylenimine and alginate (with glutaraldehyde crosslinking). SEM illustrates the macroporous structure of the material. The material is characterized by FTIR before and after chromate anions sorption. Batch-simulated continuous sorption experiments revealed that the maximum sorption occurred at pH 2 and the flow rate has limited effect on sorption efficiency. Uptake kinetics and sorption isotherms are well fitted by the pseudo-second-order rate and Sips equations, respectively. Maximum sorption is found close to 314 mg g-1. Competition effects from Ca(II), Cu(II), Cl-, NO3-, and SO42- are investigated to evaluate sorbent selectivity. The membranes are applied to remediate a simulate of Cr(VI) contaminated electroplating wastewater. Successive cycles of sorption and desorption show that the membranes maintain sorption capacity higher than 200 mg Cr g-1 for both Cr(VI) and total chromium for the first two cycles. These new highly percolating membranes have promising performances for Cr(VI) removal.

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