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1.
Int J Biol Macromol ; 2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34785197

RESUMO

Biologically active bacterial cellulose (BC) was efficiently synthesized in situ using wine pomace and its hydrolysate. The structural and biomechanical properties together with the biological functions of the BC were investigated. Functional BC from wine pomace and its enzymatic hydrolysate were of high purity and had higher crystallinity indexes (90.61% and 89.88%, respectively) than that from HS medium (82.26%). FTIR results proved the in-situ bindings of polyphenols to the functionalized BC. Compared to BC from HS medium, wine pomace-based BC had more densely packed ultrafine fibrils, higher diameter range distributions of fiber ribbon, but lower thermal decomposition temperatures, as revealed by the SEM micrographs and DSC data. Meanwhile, wine pomace-based BC exhibited higher loads in tensile strength and higher hardness (4.95 ± 0.31 N and 5.13 ± 0.63 N, respectively) than BC in HS medium (3.43 ± 0.14 N). Furthermore, BC synthesized from wine pomace hydrolysate exhibited a slower release rate of phenolic compounds, and possessed more antioxidant activities and better bacteriostatic effects than BC from wine pomace. These results demonstrate that BC synthesized in situ from wine pomace (especially from enzymatic hydrolysate) is a promising biomolecule with a potential application in wound dressing, tissue engineering, and other biomedical fields.

2.
Oral Oncol ; 122: 105555, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34619463

RESUMO

OBJECTIVE: We undertook this study to clarify how TPF, TP and PF induction chemotherapy (IC) regimens benefit for nasopharyngeal carcinoma (NPC) patients with different risk of disease progression. MATERIALS AND METHODS: Patients with newly diagnosed, stage III-IVA NPC were included. A quantitative nomogram was built using the independent prognostic factors identified for disease-free survival (DFS). Patients were stratified into low-risk and high-risk groups by the nomogram. Survival outcomes and toxicities between different IC regimens were compared. RESULTS: In total, 1647 (41.0%), 1123 (28.0%) and 1242 (31.0%) patients received TPF, PF and TP regimen, respectively. Consequently, 2253 (56.2%) patients were clarified as low-risk group and the other 1759 (43.8%) as high-risk group. Survival outcomes did not significantly differ between TPF, PF and TP regimens within the low-risk group. However, TPF was associated with significantly improved 3-year DFS (76.2% vs. 67.5% vs. 68.3%), overall survival (88.3% vs. 84.1% vs. 83.9%), distant metastasis-free survival (81.9% vs. 75.0% vs. 77.4%) and locoregional relapse-free survival (92.0% vs. 87.5% vs. 86.9%; all P < 0.05) compared with PF and TP within high-risk group. Multivariate analysis also confirmed these findings. Toxicity analysis showed that TP regimen has the highest percentage of grade 3-5 hematologic toxicities while PF regimen achieved the lowest percentages of overall grade 3-5 adverse events. CONCLUSIONS: Patients with high risk should receive TPF for better efficacy and PF may be a better choice for low-risk patients with regard to less grade 3-5 toxicities.

3.
Polymers (Basel) ; 13(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34641060

RESUMO

Poly (lactic acid) (PLA)-Poly (propylene carbonate) (PPC) block copolymer compatibilizers are produced in incompatible 70wt%PLA/PPC blend by initiating transesterification with addition of 1% of tetra butyl titanate (TBT) or by chain extension with addition of 2% of 2,4-toluene diisocyanate (TDI). The above blends can have much better mechanical properties than the blend without TBT and TDI. The elongation at break is dramatically larger (114% with 2% of TDI and 60% with 1% of TBT) than the blend without TDI and TBT, with a slightly lower mechanical strength. A small fraction of the copolymer is likely formed in the PLA/PPC blend with addition of TBT, and a significant amount of the copolymer can be made with addition of TDI. The copolymer produced with TDI has PPC as a major content (~70 wt%) and forms a miscible interphase with its own Tg. The crystallinity of the blend with TDI is significantly lower than the blend without TDI, as the PLA blocks of the copolymer in the interphase is hardly to crystallize. The average molecular weight increases significantly with addition of TDI, likely compensating the lower mechanical strength due to lower crystallinity. Material degradation can occur with addition of TBT, but it is very limited with 1% of TBT. However, compared with the blends without TBT, the PLA crystallinity of the blend with 1%TBT increases sharply during the cooling process, which likely compensates the loss of mechanical strength due to the slightly material degradation. The added TDI does not have any significant impact on PLA lamellar packing, but the addition of TBT can make PLA lamellar packing much less ordered, presumably resulted from much smaller PPC domains formed in the blend due to better compatibility.

4.
BMC Cancer ; 21(1): 1167, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34717582

RESUMO

OBJECTIVES: To develop and validate a radiomics model for evaluating treatment response to immune-checkpoint inhibitor plus chemotherapy (ICI + CT) in patients with advanced esophageal squamous cell carcinoma (ESCC). METHODS: A total of 64 patients with advance ESCC receiving first-line ICI + CT at two centers between January 2019 and June 2020 were enrolled in this study. Both 2D ROIs and 3D ROIs were segmented. ComBat correction was applied to minimize the potential bias on the results due to different scan protocols. A total of 788 features were extracted and radiomics models were built on corrected/uncorrected 2D and 3D features by using 5-fold cross-validation. The performance of the radiomics models was assessed by its discrimination, calibration and clinical usefulness with independent validation. RESULTS: Five features and support vector machine algorithm were selected to build the 2D uncorrected, 2D corrected, 3D uncorrected and 3D corrected radiomics models. The 2D radiomics models significantly outperformed the 3D radiomics models in both primary and validation cohorts. When ComBat correction was used, the performance of 2D models was better (p = 0.0059) in the training cohort, and significantly better (p < 0.0001) in the validation cohort. The 2D corrected radiomics model yielded the optimal performance and was used to build the nomogram. The calibration curve of the radiomics model demonstrated good agreement between prediction and observation and the decision curve analysis confirmed the clinical utility. CONCLUSIONS: The easy-to-use 2D corrected radiomics model could facilitate noninvasive preselection of ESCC patients who would benefit from ICI + CT.

5.
Polymers (Basel) ; 13(20)2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34685234

RESUMO

The difference in compatibility at the molecular level can lead to a change of microphase separation structure of thermoplastic polyurethanes blend systems, which will improve their thermal and mechanical properties. In this study, TDI-polyester based TPU was blended with MDI-polyether-based TPU and MDI-polyester based TPU, with different ratios. In the blend system, the obvious reduction of the melting temperature of the high-temperature TDI-polyester based TPU component indicates its hard segments can be mutually integrated with the other component. For TDI-polyester based TPU/MDI-polyether based TPU blends, their similar hard segment ratio and similar chemical structure of the soft segment give the molecular chains of the two components better compatibility. The aggregation structure of the two kinds of chains can rearrange at the molecular level which makes the hard domains mutually integrate to form a new phase separation structure with larger phase region distance. As a result, the yield strength of this blend increased by almost 143% when the elongation at break was only reduced by 12%. In contrast, the other group of blends still partly maintain their respective micro domains, forming a weak interface and leading to a decreased of elongation at break.

7.
Front Neurosci ; 15: 692575, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34349618

RESUMO

Radiation encephalopathy (RE) is an important potential complication in patients with nasopharyngeal carcinoma (NPC) who undergo radiotherapy (RT) that can affect the quality of life. However, a functional imaging biomarker of pre-symptomatic RE has not yet been established. This study aimed to assess radiation-induced gray matter functional alterations and explore fractional amplitude of low-frequency fluctuation (fALFF) as an imaging biomarker for predicting or diagnosing RE in patients with NPC. A total of 60 patients with NPC were examined, 21 in the pre-RT cohort and 39 in the post-RT cohort. Patients in the post-RT cohort were further divided into two subgroups according to the occurrence of RE in follow-up: post-RT non-RE (n = 21) and post-RT REproved infollow-up (n = 18). Surface-based and volume-based fALFF were used to detect radiation-induced functional alterations. Functional derived features were then adopted to construct a predictive model for the diagnosis of RE. We observed that surface-based fALFF could sensitively detect radiation-induced functional alterations in the intratemporal brain regions (such as the hippocampus and superior temporal gyrus), as well as the extratemporal regions (such as the insula and prefrontal lobe); however, no significant intergroup differences were observed using volume-based fALFF. No significant correlation between fALFF and radiation dose to the ipsilateral temporal lobe was observed. Support vector machine (SVM) analysis revealed that surface-based fALFF in the bilateral superior temporal gyri and left insula exhibited impressive performance (accuracy = 80.49%) in identifying patients likely to develop RE. We conclude that surface-based fALFF may serve as a sensitive imaging biomarker in the prediction of RE.

8.
Radiother Oncol ; 160: 221-227, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33984350

RESUMO

PURPOSE: This study aimed to evaluate the prognostic value of paranasal sinus involvement (PSI) in NPC and to explore its appropriate position in the current AJCC staging system. MATERIALS AND METHODS: Pretreatment MRI of 1317 patients with NPC treated with intensity-modulated radiotherapy (IMRT) between January 2010, and January 2013, were reviewed retrospectively. Survival was compared between patients with PSI-slight (sinus bone wall erosion only) and PSI-severe (tumor penetrated into sinus cavity). Multivariable analysis was performed to identify the independent predictors of survival. RESULTS: The study included 1317 patients (median age 46 years; range, 11-78 years). PSI-slight was present in 15.2% (200/1317) patients and PSI-severe in 20.0% (263/1317) patients. Overall survival (OS), distant metastasis-free survival (DMFS), loco-regional recurrence-free survival (LRFS), and progression-free survival (PFS) were significantly lower in patients with PSI-severe (all P < .05). In multivariable analysis, PSI-severe was an independent prognostic factor for OS, DMFS, LRFS, and PFS (all P < .05). 96 AJCC T3 category patients with PSI-severe were reclassified as T4 category. The revised T category had significantly better predictive value (higher C-index) than that the AJCC system for survival (OS, 0.661 vs. 0.652; DMFS, 0.655 vs. 0.650; and PFS, 0.625 vs. 0.625; P < .05 for all). CONCLUSION: PSI-severe is an independent negative prognostic factor in nasopharyngeal carcinoma, which is recommended to be classified as T4 category in the 8th AJCC staging system for NPC.


Assuntos
Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Humanos , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos
9.
Radiother Oncol ; 155: 219-225, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33217495

RESUMO

PURPOSE: To assess the impact of tumor necrosis on treatment sensitivity and long-term survival in patients with nasopharyngeal carcinoma (NPC) treated using intensity-modulated radiation therapy (IMRT). PARTICIPANTS AND METHODS: In total, 757 patients with non-metastatic, histologically confirmed NPC were retrospectively examined. All patients were treated using IMRT; 93.7% patients with stage T3-T4/N1-N3 disease also received cisplatin-based chemotherapy. RESULTS: The incidence rates of tumor necrosis in primary tumor, retropharyngeal lymph nodes, neck lymph nodes, and total tumor were 2%, 17.7%, 21.5%, and 31.4%. Overall, 40.8% patients with necrosis of the total tumor achieved complete response (CR) and 54.7% patients without tumor necrosis achieved CR at the end of treatment (χ2 = 12.728, P < 0.001). The estimated 7-year overall survival (OS), failure-free survival (FFS), distant metastasis-free survival (DMFS), and loco-regional relapse-free survival (LRRFS) for patients with tumor necrosis and without tumor necrosis of the total tumor were 68.5% vs. 88.4%, 70.5% vs. 88.1%, 77.6% vs. 90.6%, and 85.9% vs. 91.3%, respectively (all P < 0.001). Multivariate analyses indicated that necrosis of the total tumor was an independent predictor of OS, FFS, DMFS, and LRRFS. The impact of lymph node necrosis on long-term survival was similar to that of necrosis of the total tumor. ROC curves verified that inclusion of lymph node necrosis improved the predictive value of the current N classification criteria (P = 0.006). CONCLUSIONS: Tumor necrosis served as a predictor of treatment sensitivity and poor prognosis for patients with NPC. Lymph node necrosis significantly improved the prognostic value of the current N classification criteria for NPC.


Assuntos
Carcinoma , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Carcinoma/patologia , Carcinoma/terapia , Intervalo Livre de Doença , Humanos , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Necrose , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos
10.
J Natl Cancer Inst ; 113(4): 471-480, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33094348

RESUMO

BACKGROUND: Induction chemotherapy (IC) followed by concurrent chemoradiotherapy is the mainstay treatment for patients with locoregionally advanced nasopharyngeal carcinoma. However, some patients obtain little benefit and experience unnecessary toxicities from IC. We intended to develop a gene-expression signature that can identify beneficiaries of IC. METHODS: We screened chemosensitivity-related genes by comparing gene-expression profiles of patients with short-term tumor response or nonresponse to IC (n = 95) using microarray analysis. Chemosensitivity-related genes were quantified by digital expression profiling in a training cohort (n = 342) to obtain a gene signature. We then validated this gene signature in the clinical trial cohort (n = 187) and an external independent cohort (n = 240). Tests of statistical significance are 2-sided. RESULTS: We identified 43 chemosensitivity-related genes associated with the short-term tumor response to IC. In the training cohort, a 6-gene signature was developed that was highly accurate at predicting the short-term tumor response to IC (area under the curve [AUC] = 0.87, sensitivity = 87.5%, specificity = 75.6%). We further found that IC conferred failure-free survival benefits only in patients in the benefit group (hazard ratio [HR] = 0.54, 95% confidence interval [CI] = 0.34 to 0.87; P = .01) and not on those in the no-benefit group (HR = 1.25, 95% CI = 0.62 to 2.51; P = .53). In the clinical trial cohort, the 6-gene signature was also highly accurate at predicting the tumor response (AUC = 0.82, sensitivity = 87.5%, specificity = 71.8%) and indicated failure-free survival benefits. In the external independent cohort, similar results were observed. CONCLUSIONS: The 6-gene signature can help select beneficiaries of IC and lay a foundation for a more individualized therapeutic strategy for locoregionally advanced nasopharyngeal carcinoma patients.


Assuntos
Expressão Gênica , Quimioterapia de Indução , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Adulto , Idoso , Área Sob a Curva , Estudos de Coortes , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Sensibilidade e Especificidade , Resultado do Tratamento
11.
Radiother Oncol ; 156: 113-119, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33310007

RESUMO

PURPOSE: To evaluate how prevertebral space involvement (PSI) and degree of tumor extension within the space affects prognosis in nasopharyngeal carcinoma (NPC). PARTICIPANTS AND METHODS: Data of patients with newly-diagnosed nonmetastatic NPC (n = 757) were retrospectively analyzed. Patients were separated into groups according to presence or absence of PSI and degree of tumor spread. Overall survival (OS), failure-free survival (FFS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) were compared between the groups. RESULTS: Prevalence of PSI, simple prevertebral muscle involvement (PMI), and behind prevertebral muscle involvement (BPMI) were 44.9% (340/757), 22.5% (170/757), and 22.5% (170/757), respectively. OS, FFS, LRFS, and DMFS for patients with and without PSI were 64% vs. 84.8%, 68% vs. 85.6%, 85.8% vs. 94.4%, and 78.5% vs. 92.8%, respectively (all P < 0.001). PSI was an independent predictor of OS, FFS, LRFS, and DMFS. OS, FFS, and DMFS for patients with simple PMI and with BPMI were 72.7% vs. 54.8% (P = 0.002), 75.8% vs. 59.8% (P = 0.003), and 85.5% vs. 71.2% (P = 0.002), respectively. Degree of PSI extension was related to OS, FFS, and DMFS. OS, FFS, LRFS, and DMFS were significantly poorer in patients with PSI in T2-3 stage than in patients without PSI in T3 stage (P < 0.05), but comparable to those in patients with T4 stage (P > 0.05). CONCLUSIONS: PSI predicts poor prognosis in NPC. Survival is poorer in patients with BPMI than in those with simple PMI. NPC with PSI should be classified as T4 stage.


Assuntos
Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Humanos , Imageamento por Ressonância Magnética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos
12.
IEEE Trans Cybern ; 51(11): 5397-5408, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32248143

RESUMO

Segmentation of colorectal cancerous regions from 3-D magnetic resonance (MR) images is a crucial procedure for radiotherapy. Automatic delineation from 3-D whole volumes is in urgent demand yet very challenging. Drawbacks of existing deep-learning-based methods for this task are two-fold: 1) extensive graphics processing unit (GPU) memory footprint of 3-D tensor limits the trainable volume size, shrinks effective receptive field, and therefore, degrades speed and segmentation performance and 2) in-region segmentation methods supported by region-of-interest (RoI) detection are either blind to global contexts, detail richness compromising, or too expensive for 3-D tasks. To tackle these drawbacks, we propose a novel encoder-decoder-based framework for 3-D whole volume segmentation, referred to as 3-D RoI-aware U-Net (3-D RU-Net). 3-D RU-Net fully utilizes the global contexts covering large effective receptive fields. Specifically, the proposed model consists of a global image encoder for global understanding-based RoI localization, and a local region decoder that operates on pyramid-shaped in-region global features, which is GPU memory efficient and thereby enables training and prediction with large 3-D whole volumes. To facilitate the global-to-local learning procedure and enhance contour detail richness, we designed a dice-based multitask hybrid loss function. The efficiency of the proposed framework enables an extensive model ensemble for further performance gain at acceptable extra computational costs. Over a dataset of 64 T2-weighted MR images, the experimental results of four-fold cross-validation show that our method achieved 75.5% dice similarity coefficient (DSC) in 0.61 s per volume on a GPU, which significantly outperforms competing methods in terms of accuracy and efficiency. The code is publicly available.

13.
Polymers (Basel) ; 14(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35012161

RESUMO

The dynamic crosslinking method has been widely used to prepare rubber/plastic blends with thermoplastic properties, and the rubber phase is crosslinked in these blends. Both polyolefin elastomer (POE) and ethylene-propylene-diene monomer rubber (EPDM) can be crosslinked, which is different from usual dynamic crosslinking components. In this paper, dynamic crosslinked POE/EPDM blends were prepared. For POE/EPDM blends without dynamic crosslinking, EPDM can play a nucleation role, leading to POE crystallizing at a higher temperature. After dynamic crosslinking, the crosslinking points hinder the mobility of POE chains, resulting in smaller crystals, but having too many crosslinking points suppresses POE crystallization. Synchrotron radiation studies show that phase separation occurs and phase regions form in non-crosslinked blends. After crosslinking, crosslinking points connecting EPDM and part of POE chains, enabling more POE to enter the EPDM phase and thus weakening phase separation, indicates that dynamic crosslinking improves the compatibility of POE/EPDM, also evidenced by a lower ß conversion temperature and higher α conversion temperature than neat POE from dynamic mechanical analysis. Moreover, crosslinking networks hinder the crystal fragmentation during stretching and provide higher strength, resulting in 8.3% higher tensile strength of a 10 wt% EPDM blend than neat POE and almost the same elongation at break. Though excessive crosslinking points offer higher strength, they weaken the elongation at break.

15.
Cancer Med ; 9(19): 7100-7106, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32794334

RESUMO

OBJECTIVES: To investigate the prognostic value of magnetic resonance imaging (MRI)-determined cervical lymph node (CLN) size in nasopharyngeal carcinoma (NPC). METHODS: We retrospectively reviewed 2066 patients with NPC treated with intensity-modulated radiotherapy, and randomly divided them into two groups, in a 1:1 ratio. One group was used for training (the training group), and the other one was for internal validation (the validation group). All patients had undergone MRI examination and the maximal axial diameters (MAD) of the axial plane of all positive nodes had been measured and recorded. RESULTS: Of 683 patients with CLN metastases in the training group (n = 1033), MAD = 4 cm was associated with worse OS (64.7% vs 84.6%, P < .001), DFS (55.9% vs 76.3%, P = .001), and DMFS (67.6% vs 86.1%, P = .001). Multivariate analysis showed that MAD = 4 cm was a significant negative prognostic factor for OS (HR = 2.058; P = .025), DFS (HR = 1.727; P = .049), and DMFS (HR = 2.034; P = .036). When MRI-determined MAD = 4 cm was classified as N3 in the N classification, the OS, DFS, DMFS, and RRFS survival curves were well separated. The OS, DFS, DMFS, and RRFS concordance indexes were not statistically different between the proposed N staging system and the UICC/AJCC staging system in the training group, or between the training group and the validation group (all P = .05). CONCLUSION: MAD = 4 cm on axial MRI slices can be recommended as a prognostic factor in future versions of the UICC/AJCC NPC staging system.


Assuntos
Linfonodos/diagnóstico por imagem , Imageamento por Ressonância Magnética , Carcinoma Nasofaríngeo/diagnóstico por imagem , Neoplasias Nasofaríngeas/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Intervalo Livre de Progressão , Radioterapia de Intensidade Modulada , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
16.
Polymers (Basel) ; 12(3)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197387

RESUMO

Maleic anhydride (MAH) grafting to different polyolefins with similar grafting degree can have different effects on crystallization, crystal structure, and mechanical and thermal properties. The grafting leads to a smaller crystal size, less ordered lamellar structure, and a shorter long period for HDPE, LLDPE, and PP. The grafting makes PP lamellar packing less ordered the most and almost no effect to LLDPE. The grafting does not have that much impact on the crystallization ability of the HDPE, LLDPE, and HDPE/PP blend, but appreciably reduces the crystalline ability of PP-g-MAH, due to a dramatical drop in its molecular weight during the grafting process. As a result, the grafting makes PP a very brittle material with a lowered average melting point than the corresponding neat PP, but the grafting has almost no effect on elongation at break for LLDPE and some effect on HDPE (decreased by one-third). However, the PP degradation due to MAH grafting can be avoided in the presence of PE component, i.e., making the grafting of PP and PE at the same time with HDPE/PP blend. The grafted HDPE/PP blend shows a significantly improved compatibility, which leads to overall appreciably better mechanical properties than the neat HDPE/PP blend.

17.
Brain Imaging Behav ; 14(5): 1964-1978, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31264197

RESUMO

Radiation encephalopathy (RE) is a common complication in patients with nasopharyngeal carcinoma (NPC) who have received radiotherapy (RT), and recent neuroimaging studies have shown brain alterations in Post-RT patients prior to RE. However, whether there are functional alterations between those Post-RT patients who are proved to have RE in follow-up and those who do not develop it remains largely unknown. Here, we used resting state functional MRI to explore regional homogeneity (ReHo) and functional connectivity (FC) alterations in Post-RT patients with (Post-RT RE proved; n = 18) or without (Post-RT non-RE; n = 22) RE at follow-up, also making comparisons with a Pre-RT group (n = 23). Compared with the Pre-RT group, patients in Post-RT non-RE and Post-RT RE proved groups showed concurrent increased and decreased ReHo values in different brain regions inside and/or outside the radiation field, with the alterations in ReHo tending to increase if RE occurred. Seed-based FC analysis showed that compared with the Post-RT non-RE group, patients in the Post-RT RE proved group had different changing patterns of FC between a region of interest (ROI) in the right temporal lobe and distant brain regions (mainly in the sensorimotor system and default mode network). Receiver operating characteristic (ROC) curve analysis showed that the altered ReHo value in the ROI had excellent diagnostic performance for differentiating NPC patients who developed RE in follow-up from those who did not, with an area under the curve (AUC) value of 0.94. These ReHo and FC findings may provide new insights into the early diagnosis of RE.


Assuntos
Encefalopatias/etiologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Carcinoma Nasofaríngeo/fisiopatologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/fisiopatologia , Neoplasias Nasofaríngeas/radioterapia , Adulto , Encéfalo/diagnóstico por imagem , Encefalopatias/diagnóstico por imagem , Encefalopatias/patologia , Encefalopatias/fisiopatologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/patologia
18.
Cancer Commun (Lond) ; 39(1): 75, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730020

RESUMO

BACKGROUND: The National Comprehensive Cancer Network guidelines recommend intensity-modulated radiotherapy (IMRT) as the primary curative treatment for newly diagnosed nasopharyngeal carcinoma (NPC), but the radiation-related complications and relatively high medical costs remain a consequential burden for the patients. Endoscopic nasopharyngectomy (ENPG) was successfully applied in recurrent NPC with radiation free and relatively low medical costs. In this study, we examined whether ENPG could be an effective treatment for localized stage I NPC. METHODS: Ten newly diagnosed localized stage I NPC patients voluntarily received ENPG alone from June 2007 to September 2017 in Sun Yat-sen University Cancer Center. Simultaneously, the data of 329 stage I NPC patients treated with IMRT were collected and used as a reference cohort. The survival outcomes, quality of life (QOL), and medical costs between two groups were compared. RESULTS: After a median follow-up of 59.0 months (95% CI 53.4-64.6), no death, locoregional recurrence, or distant metastasis was observed in the 10 patients treated with ENPG. The 5-year overall survival, local relapse-free survival, regional relapse-free survival, and distant metastasis-free survival among the ENPG-treated patients was similar to that among the IMRT-treated patients (100% vs. 99.1%, 100% vs. 97.7%, 100% vs. 99.0%, 100% vs. 97.4%, respectively, P > 0.05). In addition, compared with IMRT, ENPG was associated with decreased total medical costs ($ 4090.42 ± 1502.65 vs. $ 12620.88 ± 4242.65, P < 0.001) and improved QOL scores including dry mouth (3.3 ± 10.5 vs. 34.4 ± 25.8, P < 0.001) and sticky saliva (3.3 ± 10.5 vs. 32.6 ± 23.3, P < 0.001). CONCLUSIONS: ENPG alone was associated with promising long-term survival outcomes, low medical costs, and satisfactory QOL and might therefore be an alternative strategy for treating newly diagnosed localized stage I NPC patients who refused radiotherapy. However, the application of ENPG should be prudent, and prospective clinical trials were needed to further verify the results.


Assuntos
Carcinoma Nasofaríngeo/radioterapia , Carcinoma Nasofaríngeo/cirurgia , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/cirurgia , Radioterapia de Intensidade Modulada , Adulto , Idoso , Feminino , Custos de Cuidados de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/economia , Carcinoma Nasofaríngeo/economia , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/economia , Neoplasias Nasofaríngeas/patologia , Qualidade de Vida , Radioterapia de Intensidade Modulada/economia , Adulto Jovem
19.
Int J Cancer ; 145(10): 2873-2883, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31044420

RESUMO

We analyzed the number of circulating tumor cells (CTCs) and Epstein-Barr virus DNA (EBV DNA) for diagnosis, monitoring and prognosis of patients with metastatic nasopharyngeal carcinoma (mNPC). The levels of CTCs and EBV DNA were measured at baseline and after first-line chemotherapy in 148 mNPC patients prospectively enrolled between December 2014 and August 2016. We also collected 122 non-mNPC cases within the same time frame for examining CTCs and EBV DNA at baseline. In 270 NPC patients, we observed improved specificity (86.0% vs. 41.0%) and inferior sensitivity (42.3% vs. 81.3%) of CTCs as compared to EBV DNA for diagnosis of distant metastasis. mNPC patients were stratified into unfavorable and favorable prognostic groups, respectively, based on CTC of 12 at baseline and 1 after first-line chemotherapy and EBV DNA of 10,000 at baseline and 4,000 after first-line chemotherapy. Conversion of baseline unfavorable CTCs and EBV DNA to favorable after first-line chemotherapy was associated with significantly longer progression-free survival (PFS) and overall survival (OS) compared to patients with unfavorable CTCs and EBV DNA at both time points. Among patients with a complete/partial response as per imaging evaluation, favorable CTCs and EBV DNA levels after first-line chemotherapy were associated with significantly longer PFS and OS. In conclusion, our data demonstrated the number of CTCs and EBV DNA before, after and during first-line chemotherapy were strong predictive markers for mNPC patients. When utilized in conjunction with imaging studies, CTCs and EBV DNA could provide additional prognostic information.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/sangue , Herpesvirus Humano 4/isolamento & purificação , Carcinoma Nasofaríngeo/mortalidade , Neoplasias Nasofaríngeas/mortalidade , Células Neoplásicas Circulantes , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/genética , DNA Viral/sangue , DNA Viral/genética , Feminino , Herpesvirus Humano 4/genética , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/sangue , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/patologia , Valor Preditivo dos Testes , Prognóstico , Intervalo Livre de Progressão , Estudos Prospectivos , Adulto Jovem
20.
Clin Cancer Res ; 25(14): 4271-4279, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30975664

RESUMO

PURPOSE: We aimed to evaluate the value of deep learning on positron emission tomography with computed tomography (PET/CT)-based radiomics for individual induction chemotherapy (IC) in advanced nasopharyngeal carcinoma (NPC). EXPERIMENTAL DESIGN: We constructed radiomics signatures and nomogram for predicting disease-free survival (DFS) based on the extracted features from PET and CT images in a training set (n = 470), and then validated it on a test set (n = 237). Harrell's concordance indices (C-index) and time-independent receiver operating characteristic (ROC) analysis were applied to evaluate the discriminatory ability of radiomics nomogram, and compare radiomics signatures with plasma Epstein-Barr virus (EBV) DNA. RESULTS: A total of 18 features were selected to construct CT-based and PET-based signatures, which were significantly associated with DFS (P < 0.001). Using these signatures, we proposed a radiomics nomogram with a C-index of 0.754 [95% confidence interval (95% CI), 0.709-0.800] in the training set and 0.722 (95% CI, 0.652-0.792) in the test set. Consequently, 206 (29.1%) patients were stratified as high-risk group and the other 501 (70.9%) as low-risk group by the radiomics nomogram, and the corresponding 5-year DFS rates were 50.1% and 87.6%, respectively (P < 0.0001). High-risk patients could benefit from IC while the low-risk could not. Moreover, radiomics nomogram performed significantly better than the EBV DNA-based model (C-index: 0.754 vs. 0.675 in the training set and 0.722 vs. 0.671 in the test set) in risk stratification and guiding IC. CONCLUSIONS: Deep learning PET/CT-based radiomics could serve as a reliable and powerful tool for prognosis prediction and may act as a potential indicator for individual IC in advanced NPC.


Assuntos
Aprendizado Profundo/estatística & dados numéricos , Quimioterapia de Indução/métodos , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Nomogramas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/tratamento farmacológico , Prognóstico , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
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