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Abstract Background This study aimed to explore the incidence of occult lymph node metastasis (OLM) in clinical T1 − 2N0M0 (cT1 − 2N0M0) small cell lung cancer (SCLC) patients and develop machine learning prediction models using preoperative intratumoral and peritumoral contrast-enhanced CT-based radiomic data. Methods By conducting a retrospective analysis involving 242 eligible patients from 4 centeres, we determined the incidence of OLM in cT1 − 2N0M0 SCLC patients. For each lesion, two ROIs were defined using the gross tumour volume (GTV) and peritumoral volume 15 mm around the tumour (PTV). By extracting a comprehensive set of 1595 enhanced CT-based radiomic features individually from the GTV and PTV, five models were constucted and we rigorously evaluated the model performance using various metrics, including the area under the curve (AUC), accuracy, sensitivity, specificity, calibration curve, and decision curve analysis (DCA). For enhanced clinical applicability, we formulated a nomogram that integrates clinical parameters and the rad_score (GTV and PTV). Results The initial investigation revealed a 33.9% OLM positivity rate in cT1 − 2N0M0 SCLC patients. Our combined model, which incorporates three radiomic features from the GTV and PTV, along with two clinical parameters (smoking status and shape), exhibited robust predictive capabilities. With a peak AUC value of 0.772 in the external validation cohort, the model outperformed the alternative models. The nomogram significantly enhanced diagnostic precision for radiologists and added substantial value to the clinical decision-making process for cT1 − 2N0M0 SCLC patients. Conclusions The incidence of OLM in SCLC patients surpassed that in non-small cell lung cancer patients. The combined model demonstrated a notable generalization effect, effectively distinguishing between positive and negative OLMs in a noninvasive manner, thereby guiding individualized clinical decisions for patients with cT1 − 2N0M0 SCLC.

Summary: Both concurrent chemoradiotherapy (CCRT) and induction chemotherapy (ICT) followed by CCRT are standard care of advanced nasopharyngeal carcinoma (NPC). However, tailoring personalized treatment is lacking. Herein, we established a radiogenomic clinical decision support system to classify patients into three subgroups according to their predicted disease-free survival (DFS) with CCRT and ICT response. The CCRT-preferred group was suitable for CCRT since they achieved good survival with CCRT, which could not be improved by ICT. The ICT-preferred group was suitable for ICT plus CCRT since they had poor survival with CCRT; additional ICT could afford an improved DFS. The clinical trial–preferred group was suitable for clinical trials since they exhibited poor survival regardless of receiving CCRT or ICT plus CCRT. These findings suggest that our radiogenomic clinical decision support system could identify optimal candidates for CCRT, ICT plus CCRT, and clinical trials, and may thus aid in personalized management of advanced NPC.

Objective To evaluate the effect of hematopoietic stem cell mobilization and collection in healthy pediatric donors. Methods 67 healthy pediatric donors were included in this study.According to the donor/recipient （D/R） body weight ratio （BWR）， they were divided into three groups： D/R BWR2 group （n = 14）. The mobilization， collection effect and adverse reactions of bone marrow and peripheral blood stem cells were compared among all groups. Results The quantity of mononuclear cells （MNCs） of bone marrow stem cells collected in the D/R BWR2 group （both P < 0.001）. There was no significant difference in the quantity of bone marrow CD34+ cells among three groups （all P > 0.05）. The quantity of MNCs of peripheral blood stem cells in the D/R BWR>2 group was significantly higher than those in the D/R BWR2 group was significantly higher than that in the D/R BWR

Summary: Background: Previous studies demonstrated that induction chemotherapy (IC) followed by de-escalated chemoradiotherapy adapted to tumor response was effective in treating childhood nasopharyngeal carcinoma (NPC), but the toxicity profile of this treatment strategy, and whether childhood patients with advanced stages can obtain enough benefits from it requires further investigation. Methods: We conducted a single-center phase II trial (NCT03020329). All participants received 3 cycles of paclitaxel liposome, cisplatin and 5-fluorouracil (TPF)-based IC. Patients who showed complete or partial response received de-escalated radiotherapy of 60 Gy with 3 cycles of concurrent cisplatin, and those who showed stable or progressive disease received standard-dose radiotherapy of 70 Gy with concurrent cisplatin. The primary endpoint was the complete response (CR) rate at the end of concurrent chemoradiotherapy (CCRT). Findings: From November 2016 to March 2021, 44 patients were recruited in the cohort. The CR rate was 80% (35/44, 95% CI, 65–90) of the whole cohort. All patients achieved CR 3 months after CCRT. By the last follow-up, the 3-year progression-free survival and overall survival were 91% (95% CI, 82–99) and 100% respectively. Dry mouth was the most common late toxicity, with an incidence of 41% (18/44), followed by skin fibrosis and hearing impairment. No patient suffered from severe late toxicity and growth retardation. Interpretation: Our results proved the efficacy and safety of TPF regimen followed by de-escalated radiotherapy with concurrent cisplatin in treating stage IVa-b childhood NPC patients. Funding: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.

It is critical to understand the factors that are associated with nasopharyngeal carcinoma (NPC) progression, metastasis and response to therapy. Here, the authors analyse primary and metastatic NPC samples using bulk and single-cell sequencing, and find two distinct evolutionary routes that lead to metastasis.

Summary: Chemotherapy remains controversial for stage II nasopharyngeal carcinoma because of its considerable prognostic heterogeneity. We aimed to develop an MRI-based deep learning model for predicting distant metastasis and assessing chemotherapy efficacy in stage II nasopharyngeal carcinoma. This multicenter retrospective study enrolled 1072 patients from three Chinese centers for training (Center 1, n = 575) and external validation (Centers 2 and 3, n = 497). The deep learning model significantly predicted the risk of distant metastases for stage II nasopharyngeal carcinoma and was validated in the external validation cohort. In addition, the deep learning model outperformed the clinical and radiomics models in terms of predictive performance. Furthermore, the deep learning model facilitates the identification of high-risk patients who could benefit from chemotherapy, providing useful additional information for individualized treatment decisions.

Polyethylene (PE)-based elastomers are the ideal choice for enhancing the compatibility of polypropylene/polyethylene (PP/PE) blends and improving the mechanical properties of PP-based materials. However, the issue of blend systems lies in the interplay between the crystallization processes. Therefore, we investigated the crystallization behavior during the cooling process of a new generation of PP/PE block copolymers (PP-b-PE) and random polypropylene (PPR, a copolymer of propylene and a small amount of ethylene or an alpha-olefin) blends using in-situ X-ray diffraction/scattering and differential scanning calorimetry (DSC) techniques. We also conducted mechanical performance tests on PPR/PP-b-PE blends at room temperature and low temperature (−5 °C). The results indicate that during the cooling process, the PP phase of PP-b-PE will follow the PPR to crystallize in advance and form a eutectic mixture, thereby enhancing the compatibility of PP/PE. Moreover, the PPR/PP-b-PE blend will form stable β-(300) crystals with excellent mechanical properties. Due to the improved compatibility of PP/PE with PP-b-PE, PE crystals are dispersed within PP crystals, providing bonding that improves the toughness of PPR under the low stiffness failure conditions of PPR/PP-b-PE blends, thereby enhancing their impact performance at low and room temperatures. This research has great significance for both recycling waste plastics and enhancing the low-temperature toughness of PPR.

The energy band structure, density of states, and optical properties of monolayers of MoS2 doped with alkaline earth metals (Be/Mg/Ca/Sr/Ba) are systematically studied based on first principles. The results indicate that all the doped systems have a great potential to be formed and structurally stable. In comparison to monolayer MoS2, doping alkaline earth metals results in lattice distortions in the doped system. Therefore, the recombination of photogenerated hole–electron pairs is suppressed effectively. Simultaneously, the introduction of dopants reduces the band gap of the systems while creating impurity levels. Hence, the likelihood of electron transfer from the valence to the conduction band is enhanced, which means a reduction in the energy required for such a transfer. Moreover, doping monolayer MoS2 with alkaline earth metals increases the static dielectric constant and enhances its polarizability. Notably, the Sr–MoS2 system exhibits the highest value of static permittivity, demonstrating the strongest polarization capability. The doped systems exhibit a red-shifted absorption spectrum in the low-energy region. Consequently, the Be/Mg/Ca–MoS2 systems demonstrate superior visible absorption properties and a favorable band gap, indicating their potential as photo-catalysts for water splitting.

Abstract 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

Radiation-induced functional and structural brain alterations are well documented in patients with nasopharyngeal carcinoma (NPC), followed by radiotherapy (RT); however, alterations in structure–function coupling remain largely unknown. Herein, we aimed to assess radiation-induced structure–function decoupling and its importance in predicting radiation encephalopathy (RE). We included 62 patients with NPC (22 patients in the pre-RT cohort, 18 patients in the post-RT-RE+ve cohort, and 22 patients in the post-RT-RE–ve cohort). A metric of regional homogeneity (ReHo)/voxel-based morphometry (VBM) was used to detect radiation-induced structure–function decoupling, which was then used as a feature to construct a predictive model for RE. Compared with the pre-RT group, patients in the post-RT group (which included post-RT-RE+ve and post-RT-RE–ve) showed higher ReHo/VBM coupling values in the substantia nigra (SN), the putamen, and the bilateral thalamus and lower values in the brain stem, the cerebellum, the bilateral medial temporal lobes (MTLs), the bilateral insula, the right precentral and postcentral gyri, the medial prefrontal cortex (MPFC), and the left inferior parietal lobule (IPL). In the post-RT group, negative correlations were observed between maximum dosage of RT (MDRT) to the ipsilateral temporal lobe and ReHo/VBM values in the ipsilateral middle temporal gyrus (MTG). Moreover, structure–function decoupling in the bilateral superior temporal gyrus (STG), the bilateral precentral and postcentral gyri, the paracentral lobules, the right precuneus and IPL, and the right MPFC exhibited excellent predictive performance (accuracy = 88.0%) in identifying patients likely to develop RE. These findings show that ReHo/VBM may be a novel effective imaging metric that reflects the neural mechanism underlying RE in patients with NPC.

The crystallization of polyethylene (PE) blends is a highly complex process, owing to the significant differences in crystallizability of the various PE components and the varying PE sequence distributions resulting from short- or long-chain branching. In this study, we examined both the resins and their blends through crystallization analysis fractionation (CRYSTAF) to understand the PE sequence distribution and differential scanning calorimetry (DSC) to investigate the non-isothermal crystallization behavior of the bulk materials. Small-angle X-ray scattering (SAXS) was utilized to study the crystal packing structure. The results showed that the PE molecules in the blends crystallize at different rates during cooling, resulting in a complicated crystallization behavior characterized by nucleation, co-crystallization, and fractionation. We compared these behaviors to those of reference immiscible blends and found that the extent of the differences is related to the disparity in crystallizability between components. Furthermore, the lamellar packing of the blends is closely associated with their crystallization behaviors, and the crystalline structure varies significantly depending on the components’ compositions. Specifically, the lamellar packing of the HDPE/LLDPE and HDPE/LDPE blends is similar to that of the HDPE component owing to its strong crystallizability, while the lamellar packing of the LLDPE/LDPE blend is approximately an average of the two neat components.

PurposeWe aimed to establish a prognostic model based on magnetic resonance imaging (MRI) radiomics features for individual distant metastasis risk prediction in patients with nasopharyngeal carcinoma (NPC).MethodsRegression analysis was applied to select radiomics features from T1-weighted (T1-w), contrast-enhanced T1-weighted (T1C-w), and T2-weighted (T2-w) MRI scans. All prognostic models were established using a primary cohort of 518 patients with NPC. The prognostic ability of the radiomics, clinical (based on clinical factors), and merged prognostic models (integrating clinical factors with radiomics) were identified using a concordance index (C-index). Models were tested using a validation cohort of 260 NPC patients. Distant metastasis-free survival (DMFS) were calculated by using the Kaplan-Meier method and compared by using the log-rank test.ResultsIn the primary cohort, seven radiomics prognostic models showed similar discrimination ability for DMFS to the clinical prognostic model (P=0.070-0.708), while seven merged prognostic models displayed better discrimination ability than the clinical prognostic model or corresponding radiomics prognostic models (all P

Abstract 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

Moony viscosity of ethylene-propylene-diene monomers (EPDMs) can have effect on the crystallization dynamics, structure, and properties of EPDM/polypropylene (PP)-based thermoplastic vulcanizates (TPVs). TPVs with two different Moony viscosities are prepared via a twin-screw extruder, respectively. Crosslinked EPDM with lower Moony viscosity has a higher crosslinking density and the nucleation effect of its crosslink point improves the crystallization ability of PP in TPV, leading to PP phase crystallization at higher temperatures. For TPV with an EPDM of higher Moony viscosity, it has higher crystallinity and the EPDM phase crystallized earlier. Synchrotron radiation studies show that the EPDM with low Moony viscosity has no obvious crystalline structure, and the prepared TPV has an obvious phase separation structure, while the TPV with higher Mooney viscosity of the EPDM does not exhibit obvious phase separation, indicating that the longer EPDM chains have better compatibility with PP in TPV, also evidenced by the almost disappearance of the PP glass transition peak in TPV, from the dynamic mechanical analysis. The longer EPDM chains in TPV provide more physical entanglement and better interaction with PP molecules, resulting in a stronger strain hardening process, longer elongation at break, and higher tensile stress in TPV.

Abstract 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

The melt-free radical grafting of glycidyl methacrylate (GMA) onto poly (lactic acid) (PLA) with styrene (St), α-methylstyrene (AMS), and epoxy resin (EP) as comonomers in a twin-screw extruder was used to prepare PLA-g-GMA graft copolymers. The prepared graft copolymers were then used as compatibilizers to prepare PLA/PPC/PLA-g-GMA blends by melt blending with PLA and polypropylene carbonate (PPC), respectively. The effects of different comonomers in the PLA-g-GMA graft copolymers on the thermal, rheological, optical, and mechanical properties and microstructure of the blends were studied. It was found that the grafting degree of PLA-g-GMA graft copolymers was increased to varying degrees after the introduction of comonomers in the PLA-g-GMA grafting reaction system. When St was used as the comonomer, the grafting degree of the PLA-g-GMA graft copolymer increased most significantly, from 0.8 to 1.6 phr. St as a comonomer also most improved the compatibility between PLA and PPC, and the haze of the blends was reduced while maintaining high transmittance. In addition, the PLA-g-GMA graft copolymer with the introduction of St as a comonomer significantly improved the impact toughness of the blends, while the thermal stability and tensile strength of the blends remained largely unchanged.

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 REprovedinfollow−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.

Abstract Background The role of pretreatment Epstein-Barr virus DNA (pre-DNA) for individualized induction chemotherapy (IC) in locoregionally advanced nasopharyngeal carcinoma (LA-NPC) still remains unknown. We aimed to address this clinical issue. Methods In total, data on 6218 patient with newly diagnosed LA-NPC receiving concurrent chemoradiotherapy (CCRT) with or without IC were retrospectively reviewed. Receiver operating characteristics (ROC) curve was adopted to calculate the cut-off value of pre-DNA based on disease-free survival (DFS). Propensity score matching (PSM) method was adopted to balance prognostic factors and match patients. Survival outcomes between IC + CCRT and CCRT groups were compared. Results Among the original cohort, no survival difference between IC + CCRT and CCRT groups was found. The cut-off value of pre-DNA was 4650 copies/ml (area under curve [AUC], 0.620; sensitivity, 0.6224; specificity, 0.5673). For patients with Pre-DNA ≤ 4650 copies/ml, the IC + CCRT and CCRT groups also achieved comparable survival outcomes (P > 0.05 for all rates). However, IC + CCRT was associated with significantly improved 3-year DFS (78.6% vs. 74.8%, P = 0.03), overall survival (OS; 91.4% vs. 87.5%, P = 0.002) and distant metastasis-free survival (DMFS; 86.0% vs. 82.2%, P = 0.036) for patient with pre-DNA > 4650 copies/ml. Multivariate analysis also confirm that IC + CCRT was an independent prognostic factor for DFS (HR, 0.817; 95% CI, 0.683–0.977; P = 0.027), OS (HR, 0.675; 95% CI, 0.537–0.848; P = 0.001) and DMFS (HR, 0.782; 95% CI, 0.626–0.976; P = 0.03). Conclusions Pre-DNA may be a feasible and powerful consideration for individualized IC apart from other baseline clinical characteristics in LA-NPC.

Abstract Background Enlarged retropharyngeal lymph nodes (RLNs) are very common in patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy. The most suitable treatment option for enlarged RLNs depends on the pathological results. However, RLN sampling is difficult and imminent in the clinic setting. We recently developed a novel minimally invasive technique termed endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for sampling RLN tissues sufficient for pathological or cytological diagnosis. Methods We enrolled 30 post-radiotherapy patients with NPC with suspected RLN metastasis detected via magnetic resonance imaging (MRI). The EUS probe was introduced into the nasopharynx via the nostrils, and EUS was then used to scan the retropharyngeal space and locate the RLN in the anterior carotid sheath. EUS-FNA was subsequently performed. The safety and efficacy of using EUS-FNA to sample the RLN tissues were assessed. Results Strips of tissue were successfully sampled from all patients using EUS-FNA. Of the 30 patients, 23 were confirmed to have cancer cells in the biopsied tissues via pathology or cytology examinations with 1 EUS-FNA biopsy session. The seven cases without confirmed cancer cells were subsequently reanalyzed by using another EUS-FNA biopsy session, and two more cases were confirmed possessing cancer cells. The other five patients without confirmed cancer cells were closely followed with MRI every month for 3 months. After follow-up for 3 months, three patients were still considered cancer-free due to the presence of RLNs with stable or shrinking diameters. The rest two patients who showed progressive disease underwent a third EUS-FNA biopsy procedure and were further confirmed to be cancer cell-positive. In the whole cohort reported here, the EUS-FNA procedure was not associated with any severe complications. Conclusion EUS-FNA is a safe and effective diagnostic approach for sampling tissues from the RLNs in patients with suspected recurrent NPC.

Abstract Ultrastable Y zeolite (USY)-supported Pt catalyst was prepared by gas-bubbling-assisted membrane reduction. The influence of reaction conditions and the metal and acid sites of catalysts on the catalytic performance of catalyst in hydrogenation and selective ring opening of tetralin, 1,2,3,4-tetrahydronaphthalene (THN), was studied. It was found that the optimal reaction conditions were at a temperature of 280 °C, hydrogen pressure of 4 MPa, liquid hourly space velocity of 2 h−1 and H2/THN ratio of 750. Under these optimal conditions, a high conversion of almost 100% was achieved on the 0.3Pt/USY catalyst. XRD patterns and TEM images revealed that Pt particles were highly dispersed on the USY, favorable to the hydrogenation reaction of tetralin. Ammonia temperature-programmed desorption and Py-IR results indicated that the introduction of Pt can reduce the acid sites of USY, particularly the strong acid sites of USY. Thus, the hydrocracking reaction can be suppressed.

Abstract Background Little is known about the prognostic difference of anti-EGFR therapy, cetuximab (CTX) or nimotuzumab (NTZ), concurrently with induction chemotherapy (IC, investigational arm) or RT (control arm) for patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC). We conducted this retrospective study to address this. Methods We identified 296 patients with newly diagnosed LA-NPC at Sun Yat-Sen University Cancer Center between January 2012 and May 2015. Patients were treated by IC with CCRT or RT and CTX/NTZ was delivered during IC or radiotherapy. Survival outcomes and toxicities between different arms were compared. Results In total, there were 149 patients in the investigational arm and 147 in control arm. The 3-year disease-free survival, overall survival, distant metastasis-free survival and locoregional relapse-free survival rates for investigational arm vs. control arm were 84.3% vs. 74.3% (P = 0.027), 94.0% vs. 92.1% (P = 0.673), 88.0% vs. 81.8% (P = 0.147) and 93.3% vs. 88.0% (P = 0.093). Multivariate analysis revealed patients in the control arm achieved significantly worse disease-free survival (HR, 1.497; 95% CI, 1.016–2.206; P = 0.026) compared with those in the investigational arm; however, no significant difference was identified for other endpoints. Patients in the investigational arm experienced more grade 3–4 skin reaction (15.4% vs. 2.0%, P

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 β 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.

Abstract Background Little is known about the nature of metastasis to small cervical lymph nodes (SCLNs) in the patients with nasopharyngeal carcinoma (NPC) examined by using 18-fluoro-2-deoxy-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT). The present study aimed to evaluate the diagnostic values of PET/CT in identifying metastasis in SCLNs in NPC patients. Methods Magnetic resonance images (MRI) and PET/CT scans for 470 patients with newly diagnosed, non-distant metastatic NPC were analyzed. Metastatic rates of SCLNs were defined by the positive number of SCLNs on PET/CT scans and total number of SCLNs on MRI scans. Receiver operating characteristic curve was applied to compare PET/CT-determined stage with MRI-determined stage. Results In total, 2082 SCLNs were identified, with 808 (38.8%) ≥ 5 and

Abstract Background According to the 7th edition of the American Joint Committee on Cancer (AJCC) staging system, over 50% of patients with nasopharyngeal carcinoma (NPC) have N1 disease at initial diagnosis. However, patients with N1 NPC are relatively under-researched, and the metastasis risk of this group is not well-stratified. This study aimed to evaluate the prognostic values of gross tumor volume of metastatic regional lymph node (GTVnd) and pretreatment serum copy number of Epstein–Barr virus (EBV) DNA in predicting distant metastasis of patients with N1 NPC, and to develop an integrated prognostic model that incorporates GTVnd and EBV DNA copy number for this group of patients. Methods The medical records of 787 newly diagnosed patients with nonmetastatic, histologically proven N1 NPC who were treated at Sun Yat-sen University Cancer Center between November 2009 and February 2012 were analyzed. Computed tomography-derived GTVnd was measured using the summation-of-area technique. Blood samples were collected before treatment to quantify plasma EBV DNA. The receiver operating characteristic (ROC) curve analysis was used to evaluate the cut-off point for GTVnd, and the area under the ROC curve was used to assess the predicted validity of GTVnd. The survival rates were assessed by Kaplan–Meier analysis, and the survival curves were compared using a log-rank test. Multivariate analysis was conducted using the Cox proportional hazard regression model. Results The 5-year distant metastasis-free survival (DMFS) rates for patients with GTVnd > 18.9 vs. ≤ 18.9 mL were 82.2% vs. 93.2% (P 4000 vs. ≤ 4000 copies/mL were 83.5% vs. 93.9% (P 18.9 mL and EBV DNA copy number > 4000 copies/mL were significantly associated with poor prognosis (both P

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.

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.

Abstract Background Nasopharyngeal carcinoma (NPC) shows a high proportion of lymph node metastasis, and treatment guidelines have been developed for positive nodes. However, no irradiation guidelines have been proposed for patients with enlarged neck lymph nodes (ENLNs) that do not meet the radiological criteria of 10 mm in diameter for positive lymph nodes. This study aimed to determine the prognostic value and radiation dose for ENLNs in N0-category NPC patients treated with intensity-modulated radiotherapy (IMRT). Methods We reviewed the medical data of 251 patients with non-metastatic, N0-category NPC treated with IMRT. Receiver operating characteristic curves were used to calculate the cut-off value of the ENLN diameter for the prediction of disease failure. The biological equivalent dose (BED) for ENLNs was calculated. Patient survival was compared between the small and large ENLN groups. Independent prognostic factors were identified using the Cox proportional hazards model. Results The estimated 4-year regional relapse-free survival rate was higher in patients with ENLNs ≥5.5 mm than in those with ENLNs 0.05 for all survival rates). In the subgroup analysis, patients receiving BED ≥72 Gy had a similar prognosis as patients receiving BED

Background: In small fiber neuropathy (SFN), thinly myelinated Aδ and unmyelinated C fibers are primarily affected, resulting in sensory and/or autonomic symptoms. Various etiologies have been shown to be associated with SFN. This study was aimed to analyze a variety of features in peripheral neuropathy (PN) with small fiber involvement, and to compare disease severity among patients with idiopathic PN, PN associated with impaired glucose tolerance (IGT), and metabolic syndrome (MS) PN. Methods: Thirty-eight PN patients with small fiber involvement were enrolled from December 20, 2013 to May 31, 2016. Patients were divided into idiopathic PN, IGT-related PN, and MS-related PN groups. Detailed medical history and small fiber neuropathy were investigated, and symptom inventory questionnaire was conducted, as well as the visual analog scale. Nerve conduction studies and skin biopsies were also performed. The differences among the groups were analyzed using analysis of variance and Kruskal-Wallis test. Results: Eight patients were diagnosed with pure SFN. Intraepidermal nerve fiber density (IENFD) weakly correlated with motor conduction velocity (MCV) (r = 0.372, P = 0.025), and proximal (r = 0.383, P = 0.021) and distal (r = 0.358, P = 0.032) compound muscle action potential (CMAP) of the tibial nerve. IENFD also weakly correlated with MCV of the peroneal nerve (r = 0.399, P = 0.016). IENFD was shown to be significantly different among all groups (χ2 = 9.901, P = 0.007). IENFD was significantly decreased (χ2 = 23.000, P = 0.003) in the MS-related PN group compared to the idiopathic PN group. The MCV of the tibial nerve was significantly different among all groups (χ2 = 8.172, P < 0.017). The proximal (F = 4.336, P = 0.021) and distal (F = 3.262, P = 0.049) CMAP of the tibial nerve was also significantly different among all groups. Conclusions: IENFD of patients included in the present study weakly correlated with various electrophysiological parameters. Small and large fibers are more involved in patients with MS-related PN than in patients with idiopathic PN.

Background: Few studies have focused on peripheral nerve conduction during exposure to microgravity. The −6° head-down tilt (HDT) comprises an experimental model used to simulate the space flight environment. This study investigated nerve conduction characteristics of rhesus monkeys before and after prolonged exposure to HDT. Methods: Six rhesus monkeys (3–4 years old) were tilted backward 6° from the horizontal. Nerve conduction studies (NCSs) were performed on the median, ulnar, tibial, and fibular motor nerves. Analysis of variance with a randomized block design was conducted to compare the differences in the NCS before and 7, 21, and 42 days after the −6° HDT. Results: The proximal amplitude of the CMAP of the median nerve was significantly decreased at 21 and 42 days of HDT compared with the amplitude before HDT (4.38 ± 2.83 vs. 8.40 ± 2.66 mV, F = 4.85, P = 0.013 and 3.30 ± 2.70 vs. 8.40 ± 2.66 mV, F = 5.93, P = 0.004, respectively). The distal amplitude of the CMAP of the median nerve was significantly decreased at 7, 21, and 42 days of HDT compared with the amplitude before HDT (7.28 ± 1.27 vs. 10.25 ± 3.40 mV, F = 4.03, P = 0.039; 5.05 ± 2.01 vs. 10.25 ± 3.40 mV, F = 6.25, P = 0.04; and 3.95 ± 2.79 vs. 10.25 ± 3.40 mV, F = 7.35, P = 0.01; respectively). The proximal amplitude of the CMAP of the tibial nerve was significantly decreased at 42 days of HDT compared with the amplitude before HDT (6.14 ± 1.94 vs. 11.87 ± 3.19 mV, F = 5.02, P = 0.039). Conclusions: This study demonstrates that the compound muscle action potential amplitudes of nerves are decreased under simulated microgravity in rhesus monkeys. Moreover, rhesus monkeys exposed to HDT might be served as an experimental model for the study of NCS under microgravity.

Abstract Background The prognostic values of staging parameters require continual re-assessment amid changes in diagnostic and therapeutic methods. This study aimed to identify the prognostic factors and failure patterns of non-metastatic nasopharyngeal carcinoma (NPC) in the intensity-modulated radiotherapy (IMRT) era. Methods We reviewed the data from 749 patients with newly diagnosed, biopsy-proven, non-metastatic NPC in our cancer center (South China, an NPC endemic area) between January 2003 and December 2007. All patients underwent magnetic resonance imaging (MRI) before receiving IMRT. The actuarial survival rates were estimated using the Kaplan–Meier method, and survival curves were compared using the log-rank test. Multivariate analyses with the Cox proportional hazards model were used to test for the independent prognostic factors by backward eliminating insignificant explanatory variables. Results The 5-year occurrence rates of local failure, regional failure, locoregional failure, and distant failure were 5.4, 3.0, 7.4, and 17.4%, respectively. The 5-year survival rates were as follows: local relapse-free survival, 94.6%; nodal relapse-free survival, 97.0%; distant metastasis-free survival, 82.6%; disease-free survival, 75.1%; and overall survival, 82.0%. Multivariate Cox regression analysis revealed that orbit involvement was the only significant prognostic factor for local failure (P = 0.011). Parapharyngeal tumor extension, retropharyngeal lymph node involvement, and the laterality, longest diameter, and Ho’s location of the cervical lymph nodes were significant prognostic factors for both distant failure and disease failure (all P

Background: Among patients with Charcot–Marie–Tooth disease (CMT), the X-linked variant (CMTX) caused by gap junction protein beta 1 (GJB1) gene mutation is the second most frequent type, accounting for approximately 90% of all CMTX. More than 400 mutations have been identified in the GJB1 gene that encodes connexin 32 (CX32). CX32 is thought to form gap junctions that promote the diffusion pathway between cells. GJB1 mutations interfere with the formation of the functional channel and impair the maintenance of peripheral myelin, and novel mutations are continually discovered. Methods: We included 79 unrelated patients clinically diagnosed with CMT at the Department of Neurology of the Chinese People's Liberation Army General Hospital from December 20, 2012, to December 31, 2015. Clinical examination, nerve conduction studies, and molecular and bioinformatics analyses were performed to identify patients with CMTX1. Results: Nine GJB1 mutations (c.283G>A, c.77C>T, c.643C>T, c.515C>T, c.191G>A, c.610C>T, c.490C>T, c.491G>A, and c.44G>A) were discovered in nine patients. Median motor nerve conduction velocities of all nine patients were < 38 m/s, resembling CMT Type 1. Three novel mutations, c.643C>T, c.191G>A, and c.610C>T, were revealed and bioinformatics analyses indicated high pathogenicity. Conclusions: The three novel missense mutations within the GJB1 gene broaden the mutational diversity of CMT1X. Molecular analysis of family members and bioinformatics analyses of the afflicted patients confirmed the pathogenicity of these mutations.