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1.
Reprod Biol Endocrinol ; 19(1): 6, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413472

RESUMO

BACKGROUND: Women who conceived with in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) are more likely to experience adverse pregnancy outcomes than women who conceived naturally. Cervical insufficiency (CI) is one of the important causes of miscarriage and premature birth, however there is no published data available focusing on the potential risk factors predicting CI occurrence in women who received IVF/ICSI treatment. This study aimed to identify the risk factors that could be integrated into a predictive model for CI, which could provide further personalized and clinically specific information related to the incidence of CI after IVF/ICSI treatment. PATIENTS AND METHODS: This retrospective study included 4710 patients who conceived after IVF/ICSI treatment from Jan 2011 to Dec 2018 at a public university hospital. The patients were randomly divided into development (n = 3108) and validation (n = 1602) samples for the building and testing of the nomogram, respectively. Multivariate logistic regression was developed on the basis of pre-pregnancy clinical covariates assessed for their association with CI occurrence. RESULTS: A total of 109 patients (2.31%) experienced CI among all the enrolled patients. Body mass index (BMI), basal serum testosterone (T), gravidity and uterine length were associated with CI occurrence. The statistical nomogram was built based on BMI, serum T, gravidity and uterine length, with an area under the curve (AUC) of 0.84 (95% confidence interval: 0.76-0.90) for the developing cohort. The AUC for the validation cohort was 0.71 (95% confidence interval: 0.69-0.83), showing a satisfactory goodness-of-fit and discrimination ability in this nomogram. CONCLUSION: The user-friendly nomogram which graphically represents the risk factors and a pre-pregnancy predicted tool for the incidence of CI in patients undergoing IVF/ICSI treatment, provides a useful guide for medical staff on individualized decisions making, where preventive measures could be carried out during the IVF/ICSI procedure and subsequent pregnancy.

2.
FASEB J ; 35(2): e21330, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33417289

RESUMO

Epilepsy is a common brain disorder, repeated seizures of epilepsy may lead to a series of brain pathological changes such as neuronal or glial damage. However, whether circular RNAs are involved in neuronal injury during epilepsy is not fully understood. Here, we screened circIgf1r in the status epilepticus model through circRNA sequencing, and found that it was upregulated after the status epilepticus model through QPCR analysis. Astrocytes polarizing toward neurotoxic A1 phenotype and neurons loss were observed after status epilepticus. Through injecting circIgf1r siRNA into the lateral ventricle, it was found that knocking down circIgf1r in vivo would induce the polarization of astrocytes to phenotype A2 and reduce neuronal loss. The results in vitro further confirmed that inhibiting the expression of circIgf1r in astrocytes could protect neurons by converting reactive astrocytes from A1 to the protective A2. In addition, knocking down circIgf1r in astrocytes could functionally promote astrocyte autophagy and relieve the destruction of 4-AP-induced autophagy flux. In terms of mechanism, circIgf1r promoted the polarization of astrocytes to phenotype A1 by inhibiting autophagy. Taken together, our results reveal circIgf1r may serve as a potential target for the prevention and treatment of neuron damage after epilepsy.

3.
J Plant Biol ; : 1-14, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33424241

RESUMO

Although morphology and grain size are important to rice growth and yield, the identity of abundant natural allelic variations that determine agronomically important differences in crops is unknown. Here, we characterized the function of mitogen-activated protein kinase 3 from Oryza officinalis Wall. ex Watt encoded by OrMKK3. Different alternative splicing variants occurred in OrMKK3. Green fluorescent protein (GFP)-OrMKK3 fusion proteins localized to the cell membrane and nuclei of rice protoplasts. Overexpression of OrMKK3 influenced the expression levels of the grain size-related genes SMG1, GW8, GL3, GW2, and DEP3. Phylogenetic analysis showed that OrMKK3 is well conserved in plants while showing large amounts of variation between indica, japonica, and wild rice. In addition, OrMKK3 slightly influenced brassinosteroid (BR) responses and the expression levels of BR-related genes. Our findings thus identify a new gene, OrMKK3, influencing morphology and grain size and that represents a possible link between mitogen-activated protein kinase and BR response pathways in grain growth. Supplementary Information: The online version contains supplementary material available at 10.1007/s12374-020-09290-2.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33410669

RESUMO

Presently, approaches to achieve superlubricity for diamond-like carbon (DLC) films rely heavily on the film deposition techniques and parameters, such as other nonmetallic element incorporation and structure optimization. In this work, we report a new feasible pathway to achieve superlubricity for DLC films, which is not dependent on the film preparation parameters but rather on the external effects, i.e., sliding interfacial addition of metal nanoparticles (Cu and Ni). The approach controls the structures of wear products by the introduction of metal nanoparticles and the subsequent effect of metal catalysts, to in situ form graphene-coated particles without impacting the overall performances of the films. Through detailed experimental investigations combined with density functional theory (DFT) simulations, graphitic encapsulation and electronic shielding of metal nanoparticles are responsible for the dramatic changes at the frictional interface leading to metal-carbon interfacial superlubricity. We expect that the approach will enrich the understanding of the lubrication mechanism of DLC films and promote the DLC films' superlubricity toward applications.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33405508

RESUMO

Conductive hydrogels have drawn significant attention in the field of stretchable/wearable sensors due to their intrinsic stretchability, tunable conductivity, biocompatibility, multistimuli sensitivity, and self-healing ability. Recent advancements in hydrogel- and organohydrogel-based sensors, including a novel sensing mechanism, outstanding performance, and broad application scenarios, suggest the great potential of hydrogels for stretchable electronics. However, a systematic summary of hydrogel- and organohydrogel-based sensors in terms of their working principles, unique properties, and promising applications is still lacking. In this spotlight, we present recent advances in hydrogel- and organohydrogel-based stretchable sensors with four main sections: improved stability of hydrogels, fabrication and characterization of organohydrogel, working principles, and performance of different types of sensors. We particularly highlight our recent work on ultrastretchable and high-performance strain, temperature, humidity, and gas sensors based on polyacrylamide/carrageenan double network hydrogel and ethylene glycol/glycerol modified organohydrogels obtained via a facile solvent displacement strategy. The organohydrogels display higher stability (drying and freezing tolerances) and sensing performances than corresponding hydrogels. The sensing mechanisms, key factors influencing the performance, and application prospects of these sensors are revealed. Especially, we find that the hindering effect of polymer networks on the ionic transport is one of the key mechanisms applicable for all four of these kinds of sensors.

6.
J Ethnopharmacol ; : 113811, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33444717

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hypecoum erectum has been used extensively in folk medicine to treat inflammation, fever, and pain. However, few investigations have been carried out on the biological activities related to its traditional use. The chemical constituents of this plant along with their anti-inflammatory and analgesic effects have yet to be revealed. AIM OF THE STUDY: This study aimed to support the traditional use of H. erectum by first assessing its anti-inflammatory and analgesic effects and then investigating its chemical constituents to identify any anti-inflammatory and/or analgesic compounds. MATERIAL AND METHODS: The in vivo anti-inflammatory and analgesic activities of the MeOH extract (ME), total alkaloid (AL), and non-alkaloid (Non-AL) fractions of H. erectum at doses of 200, 100, and 50 mg/kg and four major constituents (20, 21, 22, and 27) at doses of 100 and 50 mg/kg delivered via intragastrical administration were evaluated using carrageenan-induced paw edema and acetic acid-stimulated writhing animal models. A phytochemical study of the bioactive (AL) fraction was conducted using various chromatographic techniques, and the structures of the obtained isoquinolines were identified by multiple spectroscopic analyses and quantum chemical computations. Moreover, the anti-inflammatory activities of all the isolates were assessed in vitro based on the suppression of lipopolysaccharide-activated inflammatory mediators (COX-2, IL-1ß, and TNF-α) in RAW 264.7 macrophage cells. RESULTS: At the dose of 200 mg/kg, the three fractions (ME, AL, and Non-AL) of H. erectum ameliorated the paw edema by carrageenan-stimulated and reduced the number of writhing by acetic acid-induced in mice compared to the model group, with the AL fraction showing the most potent effects. Subsequent phytochemical investigation of the AL fraction led to the isolation of six new isoquinoline alkaloids (1-6) as well as 23 known analogues (7-29). However, compared to common isoquinolines, compounds 1-4 possess an additional nitrogen atom, while compound 5 has two additional nitrogen atoms. These additional atoms enrich the diversity of natural isoquinoline alkaloids. Further pharmacological evaluation in vivo revealed that the four major constituents (20, 21, 22, and 27) significantly relieved paw edema at 100 mg/kg, while protopine (20) and oxyhydrastinin (27) remarkably decreased the number of writhing at 100 mg/kg. In addition, most of the isolates displayed anti-inflammatory effects, as indicated by the inhibition of inflammatory mediators (COX-2, IL-1ß, and/or TNF-α) in vitro at a treatment concentration of 5 µg/mL. trans-benzindenoazepines (13), protopine (20), and 1,3,6,6-tetramethyl-5,6,7,8-tetrahyboisoquiolin-8-one (25) showed comparable anti-inflammatory activity to dexamethasone by inhibiting the secretion of IL-1ß. CONCLUSIONS: This investigation validated the traditional use of H. erectum by assessing its anti-inflammatory and analgesic effects. Phytochemical investigation revealed the diversity and novelty of the natural isoquinoline alkaloids in H. erectum. Four major isoquinolines were identified as the bioactive constituents of H. erectum. The findings provide scientific justification to support the traditional application of H. erectum for treating inflammatory and pain disorders.

7.
Angew Chem Int Ed Engl ; 60(1): 159-165, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-32931603

RESUMO

The dominated approaches for asymmetric aldol reactions have primarily focused on the aldol carbon-carbon bond-forming events. Here we postulate and develop a new catalytic strategy that seeks to modulate the reaction thermodynamics and control the product enantioselectivities via post-aldol processes. Specifically, an NHC catalyst is used to activate a masked enolate substrate (vinyl carbonate) to promote the aldol reaction in a non-enantioselective manner. This reversible aldol event is subsequently followed by an enantioselective acylative kinetic resolution that is mediated by the same (chiral) NHC catalyst without introducing any additional substance. This post-aldol process takes care of the enantioselectivity issues and drives the otherwise reversible aldol reaction toward a complete conversion. The acylated aldol products bearing quaternary/tetrasubstituted carbon stereogenic centers are formed in good yields and high optical purities.

8.
Mol Biol Evol ; 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33283852

RESUMO

The rise and expansion of Tibetan Empire in the 7th to 9th centuries AD affected the course of history across East Eurasia, but the genetic impact of Tibetans on surrounding populations remains undefined. We sequenced 60 genomes for four populations from Pakistan and Tajikistan to explore their demographic history. We showed that the genomes of Balti people from Baltistan were comprised of 22.6% ∼ 26% Tibetan ancestry. We inferred a single admixture event and dated it to about 39 to 21 generations ago, a period that postdated the conquest of Baltistan by the ancient Tibetan Empire. The analyses of mitochondrial DNA, Y, and X chromosome data indicated that both ancient Tibetan males and females were involved in the male-biased dispersal. Given the fact that the Balti people adopted Tibetan language and culture in history, our study suggested the impact of Tibetan Empire on Baltistan involved dominant cultural and minor demic diffusion.

9.
Cancer Commun (Lond) ; 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33270990

RESUMO

BACKGROUND: Conditional survival (CS) provides dynamic prognostic estimates by considering the patients existing survival time. Since CS for endemic nasopharyngeal carcinoma (NPC) is lacking, we aimed to assess the CS of endemic NPC and establish a web-based calculator to predict individualized, conditional site-specific recurrence risk. METHODS: Using an NPC-specific database with a big-data intelligence platform, 10,058 endemic patients with non-metastatic stage I-IVA NPC receiving intensity-modulated radiotherapy with or without chemotherapy between April 2009 and December 2015 were investigated. Crude CS estimates of conditional overall survival (COS), conditional disease-free survival (CDFS), conditional locoregional relapse-free survival (CLRRFS), conditional distant metastasis-free survival (CDMFS), and conditional NPC-specific survival (CNPC-SS) were calculated. Covariate-adjusted CS estimates were generated using inverse probability weighting. A prediction model was established using competing risk models and was externally validated with an independent, non-metastatic stage I-IVA NPC cohort undergoing intensity-modulated radiotherapy with or without chemotherapy (n = 601) at another institution. RESULTS: The median follow-up of the primary cohort was 67.2 months. The 5-year COS, CDFS, CLRRFS, CDMFS, and CNPC-SS increased from 86.2%, 78.1%, 89.8%, 87.3%, and 87.6% at diagnosis to 87.3%, 87.7%, 94.4%, 96.0%, and 90.1%, respectively, for an existing survival time of 3 years since diagnosis. Differences in CS estimates between prognostic factor subgroups of each endpoint were noticeable at diagnosis but diminished with time, whereas an ever-increasing disparity in CS between different age subgroups was observed over time. Notably, the prognoses of patients that were poor at diagnosis improved greatly as patients survived longer. For individualized CS predictions, we developed a web-based model to estimate the conditional risk of local (C-index, 0.656), regional (0.667), bone (0.742), lung (0.681), and liver (0.711) recurrence, which significantly outperformed the current staging system (P < 0.001). The performance of this web-based model was further validated using an external validation cohort (median follow-up, 61.3 months), with C-indices of 0.672, 0.736, 0.754, 0.663, and 0.721, respectively. CONCLUSIONS: We characterized the CS of endemic NPC in the largest cohort to date. Moreover, we established a web-based calculator to predict the CS of site-specific recurrence, which may help to tailor individualized, risk-based, time-adapted follow-up strategies.

10.
Environ Res ; 193: 110594, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33307079

RESUMO

Potentially toxic elements (PTEs) and phthalic acid esters (PAEs) often coexist in contaminated soils. Their co-existence may affect the mutual sorption behavior, and thereby influence their bioavailability and fate in soils. To our best knowledge, the impacts of plant-and animal-derived biochar on the competitive sorption-desorption of PTEs and PAEs in soils with different organic carbon content have not been studied up to date. Therefore, in this study, batch sorption-desorption experiments were conducted to investigate the influence of biochars derived from pig carcass and Platanus orientalis branches on the mono- and competitive sorption of cadmium (Cd2+) and diethyl phthalate (DEP) in soils with high (HS) and low (LS) organic carbon content. The DEP sorption was well described by Freundlich isotherm model, while Cd2+ sorption fitted better with the Langmuir isotherm model. Application of both biochars enhanced soil sorption of DEP, which increased as the application doses increased. The HS showed a stronger affinity to both DEP and Cd2+ than the LS. In the LS, the pig carcass biochar (PB) addition was more effective to increase the sorption capacity of Cd2+ and DEP and to reduce their desorption than woody biochar (WB) treatments. Moreover, the co-existing of Cd2+ could reduce the sorption of DEP, especially in the LS. The presence of DEP enhanced Cd2+ sorption in LS treated by both biochars, but the sorption of Cd2+ was suppressed with DEP addition in the PB-amended HS. In conclusion, the soil sorption capacity of DEP and Cd2+ was affected by biochar type, application dose and soil organic carbon content. The reciprocal effect between DEP and Cd2+ was also a crucial factor influencing their sorption/desorption by biochar. Therefore, PB and WB, especially PB, can be used for metal/DEP immobilization due to enhanced sorption. This approach is applicable for future remediation of soils contaminated by PTEs and PAEs.

11.
Radiother Oncol ; 156: 113-119, 2020 Dec 11.
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.

12.
Sci Total Environ ; 763: 144218, 2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33383518

RESUMO

In this study, typical animal- and plant-derived biochars derived from pig carcass (PB) and green waste (GWB), and their iron-engineered products (Fe-PB and Fe-GWB) were added at the dose of 3% (w/w) to an acidic (pH = 5.8) soil, and incubated to test their efficacy in improving soil quality and immobilizing arsenic (As = 141.3 mg kg-1) and lead (Pb = 736.2 mg kg-1). Soil properties, microbial activities, and the geochemical fractions and potential availabilities of As and Pb were determined in the non-treated (control) and biochar-treated soil. Modification of PB (pH = 10.6) and GWB (pH = 9.3) with Fe caused a decrease in their pH to 4.4 and 3.4, respectively. The application of PB and GWB significantly increased soil pH, while Fe-PB and Fe-GWB decreased soil pH, as compared to the control. Application of Fe-GWB and Fe-PB decreased the NH4H2PO4-extractable As by 32.8 and 35.9%, which was more effective than addition of GWB and PB. However, PB and GWB were more effective than Fe-PB and Fe-GWB in Pb immobilization. Compared to the control, the DTPA-extractable Pb decreased by 20.6 and 21.7%, respectively, following PB and GWB application. Both biochars, particularly PB significantly increased the 16S rRNA bacterial gene copy numbers, indicating that biochar amendments enhanced the bacterial abundance, implying an alleviation of As and Pb bio-toxicity to soil bacteria. The results demonstrated that pristine pig carcass and green waste biochars were more effective in immobilizing Pb, while their Fe-engineered biochars were more effective in As immobilization in co-contaminated soils.

14.
J Obstet Gynaecol ; : 1-5, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33228414

RESUMO

The objective of this study was to explore the correlation between cervical insufficiency (CI) and polycystic ovary syndrome (PCOS) in Chinese women undergoing assisted reproductive technology (ART) treatment. The retrospective study enrolled 2978 women including 1489 with PCOS and 1489 without PCOS, among which 34 women were diagnosed with CI (1.14%). The prevalence of CI in PCOS women was statistically higher than that in women without PCOS. Among those women with CI, 23 cases exhibited PCOS, and those cases had an average gestational age of 26.09 ± 5.91 weeks at the end of pregnancy, which was earlier than that of women without PCOS, and the pregnancy outcomes were worse than in the non-PCOS group though not statistically significant. Multivariable logistic regression showed that PCOS status (odds ratio: 2.050, 95% confidence interval: 1.009-4.206) were associated with increased risk of CI. Our study revealed that among those Chinese women who conceived by ART treatment, the prevalence of CI in women with PCOS was higher than that in women without PCOS. Co-morbidity of CI with polycystic ovarian syndrome negatively impacts prognosis. Impact statement What is already known on this subject? Women with PCOS have a higher rate of adverse obstetrical outcomes than women without PCOS. What the results of this study add? Women with PCOS were more likely to have pregnancies complicated with CI. Co-morbidity of cervical incompetence with PCOS negatively impacts prognosis. What the implications are of these findings for clinical practice and/or further research? Given these results, close surveillance of cervical changes during the second trimester in women with PCOS is necessary for reducing the risk of miscarriage related to CI.

15.
J Hazard Mater ; : 124502, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33229260

RESUMO

The biological safety of mesoporous silica nanoparticles (MSNs) has gradually attracted attention. However, few studies of their toxicity to the intestine and mechanism are available. In this study, their primary structures were characterized, and their subacute toxicity to mice was investigated. After 2 weeks of intragastric administration of MSNs, they significantly enhanced serum ALP, ALT, AST and TNF-α levels and caused infiltration of inflammatory cells in the spleen and intestines. MSNs induced intestinal oxidative stress and colonic epithelial cell apoptosis in mice. Intestinal epithelial cells exhibited mitochondrial ridge rupture and membrane potential decrease after MSN treatment. Additionally, MSNs increased ROS and NLRP3 levels and inhibited expression of the autophagy proteins LC3-II and Beclin1. MSNs significantly changed the intestinal flora diversity in mice, especially for harmful bacteria, leading to intestinal microecology imbalance. Meanwhile, MSNs influenced the expression of metabolites, which were involved in a range of metabolic pathways, including pyrimidine metabolism, central carbon metabolism in cancer, protein digestion and absorption, mineral absorption, ABC transport and purine metabolism. These results indicated that the subacute toxicity of mesoporous silicon was mainly caused by intestinal damage. Thus, our research provides additional evidence about the safe dosage of MSNs in the clinical and food industries.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33184787

RESUMO

A large amount of biochar-derived dissolved organic matter (BDOM) will be released into the environment with biochars application into repairing soil/water, which may alter the fate and transport of contaminants. In this study, four DOM samples were extracted from cauliflower root biochar (CRBC), reed straw biochar (RSBC), corn stalks biochar (CSBC), and potato stalk biochar (PSBC). Excitation-emission matrix combined with parallel factor (EEM-PARAFAC) analysis, differential absorbance spectra (DAS), and two-dimensional correlation spectroscopy (2D-COS) analysis were applied to explore the complexation property of BDOM with metals. DAS showed sites heterogeneity within the DOM pool for metals complexing. Humic-like and fulvic-like substances were main fluorescent components identified by EEM-PARAFAC. 2D-COS analysis revealed that polysaccharides and aliphatic firstly responded to Pb(II) binding with CRBC-derived DOM and three other biochar-derived DOM, respectively. While aliphatic groups, aromatic N=O, and polysaccharides gave the fastest response to Cu(II) binding with CRBC, RSBC, and the other two biochar-derived DOM, respectively.

18.
Radiother Oncol ; 155: 219-225, 2020 Nov 18.
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.

19.
Mikrochim Acta ; 187(12): 676, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33244673

RESUMO

Chirality is a universal phenomenon in nature and an essential attribute of life systems. Chiral recognition has very important research value in many fields. Amino acids and other chiral molecules are the basic components of human body. Understanding the configuration of chiral molecules is beneficial not only to the development of life science, but also to the development of chiral recognition. Compared with other traditional chiral recognition methods, electrochemical methods have the advantages of rapid detection, simple operation, low price, and high sensitivity, which has been widely concerned. In this review, we present an overview of chiral materials in a view of various chiral selectors, including amino acids and their derivatives, proteins, polysaccharides, chiral ligand exchange compounds, chiral cavity compounds (such as cyclodextrin, cucurbituril, calixarene, crown ether), and chiral ionic liquids, which were applied for the recognition of chiral molecules. Besides the chiral recognition mechanisms, some critical challenges and outlooks in the field of electrochemical chiral sensing interfaces are also discussed. Graphical abstract We have reported an overview of chiral materials in various chiral selectors, including amino acids and their derivatives, proteins, polysaccharides, chiral ligand-exchange compounds, chiral cavity, and chiral ionic liquids, which was applied for the recognition of chiral molecules. Besides chiral recognition mechanism, some critical challenges and outlooks are also discussed.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33147020

RESUMO

Conductive hydrogels have emerged as promising candidate materials for fabricating wearable electronics because of their fascinating stimuli-responsive and mechanical properties. However, the inherent instability of hydrogels seriously limits their application scope. Herein, the stable, ultrastretchable (upon to 1330% strain), self-healing, and transparent organohydrogel was exploited as a novel gas-responsive material to fabricate NH3 and NO2 gas sensors for the first time with extraordinary performance. A facile solvent substitution method was employed to convert the unstable hydrogel into the organohydrogel with a remarkable moisture retention (avoid drying within a year), frost resistance (freezing point below -130 °C), and unimpaired mechanical and gas sensing properties. First-principles simulations were performed to uncover the mechanisms of antidrying and antifreezing effects of organohydrogels and the interactions between NH3/NO2 and organohydrogels, revealing the vital role of hydrogen bonds in enhancing the stability and the adsorption of NH3/NO2 on the organohydrogel. The organohydrogel gas sensor displayed high sensitivity, ultralow theoretical limit of detection (91.6 and 3.5 ppb for NH3 and NO2, respectively), reversibility, and fast recovery at room temperature. It exhibited the capabilities to work at a highly deformed state with nondegraded sensing performance and restore all the electrical, mechanical, and sensing properties after mechanical damage. The gas sensing mechanism was understood by considering the gas adsorption on functional groups, dissolution in the solvent, and the hindering effect on the transport of ions.

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