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1.
Cancer Commun (Lond) ; 39(1): 75, 2019 Nov 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.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31637617

RESUMO

The peri-urban soil is exposed to pollutants because of its proximity to the city, which may influence the quality of agricultural products. In this study, the occurrence of 16 trace elements (TEs), 16 polycyclic aromatic hydrocarbons (PAHs), and 33 contaminants of emerging concern (CECs) was analyzed in two soil sites of the peri-urban area of Barcelona (Spain) (S2 and S3) and a pristine site (S1). Levels of Pb (S2 164 and S3 150 mg kg-1) are around 2.5 times higher than the guideline values. Values for Cu (178 mg kg-1) in S2 are 1.8-fold higher, whereas for Zn, levels are slightly above the threshold in S2 (208 mg kg-1) and S3 (217 mg kg-1). The total concentrations of PAHs are significantly below the limits: 24 ng g-1 dw (S1), 38 ng g-1 dw (S2), 49 ng g-1 dw (S3), whereas only some CECs are detected with low concentrations. We also developed a simple and rapid method to assess soil pollution. Here, we use two plant growth indexes (seed germination rate and root elongation at the initial stage) of three seeds (lettuce, tomato, and cauliflower) to assess soil chemical contamination on agriculture. In the peri-urban soil, the concentration of Pb was 2.5 times higher than the guideline values, whereas for Cu and Zn, values were slightly above their limits, while only few PAHs and CECs were detected. Results for principal component analysis suggest that root elongation is a more sensitive measurement endpoint than germination rate, especially for lettuce. The germination rate of tomato relied on the nitrate in the soil and decreased sharply in the site with pollution of Cu and As. Under the specific conditions of this study, cauliflower should not be recommended to assess environmental pollution due to its low sensitivity to pollutants. In conclusion, this is a low-cost, simple, and rapid method for evaluating the effects of chemical pollution of agriculture soils on seed growth.

3.
Cancer Res ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484669

RESUMO

The genetic events occuring in recurrent nasopharyngeal carcinoma (rNPC) are poorly understood. Here, we performed whole-genome and whole-exome sequencing in 55 rNPC and 44 primarily diagnosed NPC (pNPC) patients; with 7 patients having paired rNPC and pNPC samples. Previously published pNPC exome data were integrated for analysis. rNPC and pNPC tissues had similar mutational burdens, however, the number of clonal mutations was increased in rNPC samples. TP53 and three NF-κB pathway components (TRAF3, CYLD and NFKBIA) were significantly mutated in both pNPC and rNPC. Notably, mutations in TRAF3, CYLD and NFKBIA were all clonal in rNPC, however, 55.6-57.9% of them were clonal in pNPC. In general, the number of clonal mutations in NF-κB pathway-associated genes was significantly higher in rNPC than in pNPC. The NF-κB mutational clonality was selected and/or enriched during NPC recurrence. The amount of NF-κB translocated to the nucleus in samples with clonal NF-κB mutants was significantly higher than that in samples with subclonal NF-κB mutants. Moreover, the nuclear abundance of NF-κB protein was significantly greater in pNPC samples with local regional relapse than in those without relapse. Further, high nuclear NF-κB levels were an independent negative prognostic marker for locoregional relapse-free survival in pNPC. Lastly, inhibition of NF-κB enhanced both radiosensitivity and chemosensitivity in vitro and in vivo. In conclusion, NF-κB pathway activation by clonal mutations plays an important role in promoting the recurrence of NPC. Moreover, nuclear accumulation of NF-κB is a prominent biomarker for predicting locoregional relapse-free survival.

4.
Adv Mater ; : e1901981, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31441164

RESUMO

Recent years have witnessed the rise of graphene and its applications in various electronic devices. Specifically, featuring excellent flexibility, transparency, conductivity, and mechanical robustness, graphene has emerged as a versatile material for flexible electronics. In the past decade, facilitated by various laser processing technologies, including the laser-treatment-induced photoreduction of graphene oxides, flexible patterning, hierarchical structuring, heteroatom doping, controllable thinning, etching, and shock of graphene, along with laser-induced graphene on polyimide, graphene has found broad applications in a wide range of electronic devices, such as power generators, supercapacitors, optoelectronic devices, sensors, and actuators. Here, the recent advancements in the laser fabrication of graphene-based flexible electronic devices are comprehensively summarized. The various laser fabrication technologies that have been employed for the preparation, processing, and modification of graphene and its derivatives are reviewed. A thorough overview of typical laser-enabled flexible electronic devices that are based on various graphene sources is presented. With the rapid progress that has been made in the research on graphene preparation methodologies and laser micronanofabrication technologies, graphene-based electronics may soon undergo fast development.

5.
Angew Chem Int Ed Engl ; 58(41): 14686-14693, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31403236

RESUMO

The interaction of hydrogen with reduced ceria (CeO2-x ) powders and CeO2-x (111) thin films was studied using several characterization techniques including TEM, XRD, LEED, XPS, RPES, EELS, ESR, and TDS. The results clearly indicate that both in reduced ceria powders as well as in reduced single crystal ceria films hydrogen may form hydroxyls at the surface and hydride species below the surface. The formation of hydrides is clearly linked to the presence of oxygen vacancies and is accompanied by the transfer of an electron from a Ce3+ species to hydrogen, which results in the formation of Ce4+ , and thus in oxidation of ceria.

6.
Eur J Cancer ; 119: 87-96, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31425966

RESUMO

BACKGROUND: Initial 3-year results from our clinical trial in locoregionally advanced nasopharyngeal carcinoma (NPC) patients showed that induction chemotherapy (IC) with cisplatin and fluorouracil resulted in improved disease-free survival (DFS) with a marginally significant effect on distant metastasis-free survival (DMFS), but the effect of IC on locoregional relapse-free survival and overall survival (OS) did not differ significantly. Here, we present 5-year follow-up results. PATIENTS AND METHODS: Our trial was a randomised, open-label phase III trial comparing IC followed by concurrent chemoradiotherapy (CCRT) versus CCRT alone in patients with stage III-IVB (except T3N0-1) NPC. The IC followed by CCRT group received cisplatin (80 mg/m2 d1) and fluorouracil (800 mg/m2 d1-5) every 3 weeks for two cycles before CCRT. Both groups were treated with 80 mg/m2 cisplatin every 3 weeks concurrently with radiotherapy. The primary end-points were DFS and DMFS. We did efficacy analyses in the 476 randomised patients (intention-to-treat population). RESULTS: After a median follow-up of 82.6 months, the 5-year DFS rate was 73.4% (95% confidence interval [CI] 67.7-79.1) in the IC followed by CCRT group and 63.1% (95% CI 56.8-69.4) in the CCRT alone group (p = 0.007). The 5-year DMFS rate was also significantly higher in the IC followed by CCRT group (82.8%, 95% CI 77.9-87.7) than in the CCRT alone group (73.1%, 95% CI 67.2-79.0, p = 0.014). Our updated analysis revealed an OS benefit of IC: the 5-year OS rate was 80.8% in the IC followed by CCRT group versus 76.8% in the CCRT alone group (p = 0.040). The proportion of patients with eye damage was significantly higher in the CCRT alone group than the IC followed by CCRT group (16.4% [39/238] versus 9.7% [23/238], p = 0.029). CONCLUSION: IC followed by CCRT provides long-term DFS, DMFS and OS benefits compared with CCRT alone in locoregionally advanced NPC and, therefore, can be recommended for these patients.

7.
Angew Chem Int Ed Engl ; 58(35): 12043-12048, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31192496

RESUMO

Supported Pd catalysts are active in catalyzing the highly exothermic methane combustion reaction but tend to be deactivated owing to local hyperthermal environments. Herein we report an effective approach to stabilize Pd/SiO2 catalysts with porous Al2 O3 overlayers coated by atomic layer deposition (ALD). 27 Al magic angle spinning NMR analysis showed that Al2 O3 overlayers on Pd particles coated by the ALD method are rich in pentacoordinated Al3+ sites capable of strongly interacting with adjacent surface PdOx phases on supported Pd particles. Consequently, Al2 O3 -decorated Pd/SiO2 catalysts exhibit active and stable PdOx and Pd-PdOx structures to efficiently catalyze methane combustion between 200 and 850 °C. These results reveal the unique structural characteristics of Al2 O3 overlayers on metal surfaces coated by the ALD method and provide a practical strategy to explore stable and efficient supported Pd catalysts for methane combustion.

8.
Int J Cancer ; 145(10): 2873-2883, 2019 Nov 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.

9.
ACS Sens ; 4(5): 1261-1269, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-30990023

RESUMO

Ti3C2T x MXene with an organ-like structure was synthesized from Ti3AlC2 (MAX phase) through the typical hydrofluoric (HF) acid etching method. Ti3C2T x MXene was further alkaline-treated with a sodium hydroxide solution to obtain alkalized Ti3C2T x. Room-temperature planar-type gas- and humidity-sensing devices were also fabricated by utilizing Ti3C2T x MXene and alkalized Ti3C2T x sensing material based on the dip coating method, respectively. The intercalation of the alkali metal ion (Na+) and the increase of the surface terminal oxygen-fluorine ratio ([O]/[F]) in Ti3C2T x can effectively improve humidity- and gas-sensing properties at room temperature. The developed alkalized Ti3C2T x sensor exhibited excellent humidity-sensing characteristics (approximately 60 times response signal change) in the relative humidity (RH) with a range of 11-95% and considerable NH3 sensing performance (28.87% response value to 100 ppm of NH3) at room temperature. The improvement of NH3 and humidity-sensing properties indicated that alkalized Ti3C2T x has great potential in chemical sensors, especially in NH3 and humidity sensors.

10.
J Am Chem Soc ; 141(11): 4505-4509, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30832476

RESUMO

Developing a facile route to access active and well-defined single atom sites catalysts has been a major area of focus for single atoms catalysts (SACs). Herein, we demonstrate a simple approach to generate atomically dispersed platinum via a thermal emitting method using bulk Pt metal as a precursor, significantly simplifying synthesis routes and minimizing synthesis costs. The ammonia produced by pyrolysis of Dicyandiamide can coordinate with platinum atoms by strong coordination effect. Then, the volatile Pt(NH3) x can be anchored onto the surface of defective graphene. The as-prepared Pt SAs/DG exhibits high activity for the electrochemical hydrogen evolution reaction and selective oxidation of various organosilanes. This viable thermal emitting strategy can also be applied to other single metal atoms, for example, gold and palladium. Our findings provide an enabling and versatile platform for facile accessing SACs toward many industrial important reactions.

11.
Cancer Commun (Lond) ; 38(1): 74, 2018 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-30577735

RESUMO

BACKGROUND: Postradiation nasopharyngeal necrosis (PRNN) is a severe complication after radiotherapy in patients with nasopharyngeal carcinoma (NPC), which can severely affect the quality of life and threaten the patient's life. Only 13.4%-28.6% of patients can be cured by traditional repeated endoscopic debridement. Here, we introduced an innovative curative-intent endoscopic surgery for PRNN patients and evaluated its clinical efficacy. METHODS: Clinical data of 72 PRNN patients who underwent radical endoscopic necrectomy, followed by reconstruction using a posterior pedicle nasal septum and floor mucoperiosteum flap were analyzed to determine the efficacy of this surgery. The endpoints were complete re-epithelialization of the nasopharyngeal defect, relief of headache, and overall survival (OS). RESULTS: All surgeries were successfully performed without any severe postoperative complications or death. The median value of numeric rating scales of pain decreased from 8 before surgery to 0 after surgery (P < 0.001). Fifty-one patients (70.8%) achieved complete re-epithelialization of the nasopharyngeal defect. The number of cycles of radiotherapy (odds ratio [OR], 7.254; 95% confidence interval [CI] 1.035-50.821; P = 0.046), postoperative pathological result (OR, 34.087; 95% CI 3.168-366.746; P = 0.004), and survival status of flap (OR, 261.179; 95% CI 17.176-3971.599; P < 0.001) were independent risk factors of re-epithelialization of the nasopharyngeal defects. Postoperative pathological result (hazard ratio [HR], 5.018; 95% CI 1.970-12.782; P = 0.001) was an independent prognostic factor for OS. The 2-year OS rate of the entire cohort was 77.9%. CONCLUSION: Curative-intent endoscopic necrectomy followed by construction using the posterior pedicle nasal septum and floor mucoperiosteum flap is a novel, safe, and effective treatment of PRNN in patients with NPC.


Assuntos
Endoscopia/métodos , Carcinoma Nasofaríngeo/cirurgia , Qualidade de Vida/psicologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
J Cancer ; 9(19): 3447-3455, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30310501

RESUMO

Purpose: To directly compare the efficacy and acute toxicities of intensity-modulated radiotherapy (IMRT) concurrent with weekly cisplatin (40 mg/m2) to high-dose concurrent cisplatin (100 mg/m2) at three-week intervals. Materials and Methods: A total of 3,799 patients diagnosed with locally advanced nasopharyngeal carcinoma (NPC) at Sun Yat-Sen University Cancer Center between January 2010 and December 2013 were retrospectively reviewed. Propensity score analysis was conducted to balance the baseline characteristics between the groups, which allowed us to draw reliable conclusions. The efficacy and safety profiles were then assessed in the well-balanced large cohort. Results: The risk of distant metastasis was lower among the patients treated with weekly concurrent cisplatin than among those treated with the triweekly regimen (hazard ratio [HR], 0.45; P = .028). However, the disease-free survival, loco-regional relapse-free survival and overall survival rates were similar. The weekly group showed significantly higher rates of grade 3-4 thrombocytopenia, but lower rates of grade 3-4 mucositis, nausea and vomiting than the triweekly group. Conclusion: IMRT concurrent with a weekly cisplatin regimen was associated with significantly improved distant metastasis-free survival in locally advanced NPC. Differences in the selected acute toxicities between the weekly and triweekly concurrent cisplatin regimens were noted.

13.
Laryngoscope ; 2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30325027

RESUMO

OBJECTIVE: To compare survival effects of comprehensive neck dissection (CND) and selective neck dissection (SND) for patients with nasopharyngeal carcinoma (NPC) with only regional failure. METHODS: A total of 294 recurrent T0N1-3M0 NPC patients who underwent neck dissection in Sun Yat-Sen University Cancer Center, Guangzhou, People's Republic of China, between January 1984 and February 2014, were enrolled in the survival and interaction analyses. Using propensity scores to adjust for potential prognostic factors, an additional well-balanced cohort of 210 patients was constructed by matching each patient who received SND with one patient who underwent CND (1:1); the differences were then compared between SND and CND in terms of overall survival (OS), local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), and distant metastasis-free survival (DMFS). RESULTS: Both univariate and multivariate analyses showed that SND was not inferior to CND (P > 0.05) but demonstrated that extracapsular spread (ECS) (hazard ratio [HR] 3.49, 95% confidence interval [CI] 2.30-5.29, P < 0.001), recurrent N stage (rN stage) (HR 1.96, 95% CI 1.29-2.97, P = 0.002), and positive margins (HR 3.67, 95% CI 2.40-5.62, P < 0.001) were independent poor prognostic factors for OS. The interaction effects between the dissection style and each independent factor were not significant for OS, LRFS, RRFS, or DMFS (P > 0.05). Furthermore, no survival differences were found between SND and CND in the case-matched cohort in terms of OS, LRFS, RRFS, or DMFS (P = 0.550, 0.930, 0.214, and 0.146, respectively). CONCLUSION: With a similar radical dissection extent around the tumor rather than dissection of extensive lymph region distal to the lesion, SND is not inferior to CND for patients with NPC with only cervical failure. ECS, rN stage, and positive margins were adverse independent prognostic factors for patients with NPC. LEVEL OF EVIDENCE: 4. Laryngoscope, 2018.

14.
Huan Jing Ke Xue ; 39(8): 3759-3766, 2018 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29998684

RESUMO

A novel heterogeneous Fenton catalyst, Prussian blue@yeast (PB@yeast), was prepared via facile self-assembly synthesis. The as-synthesized composite was characterized by field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), powder X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). All of the results indicated that PB nanoparticles were uniformly dispersed on the surface of yeasts with stable core-shell morphology. Degradation of the model anionic fluorescent whitening agent CXT indicated that the PB@yeast catalyst presented a synergistic effect of adsorption and heterogeneous Fenton performance. Owing to the high adsorption capacity of yeast, the CXT molecules were easy to move to the active site of the catalyst, promoting the electron transfer between Fe(Ⅲ) and Fe(Ⅱ) and then enhancing the catalytic activity of the Fenton reaction effectively. Furthermore, the yeast support could improve the dispersity and stability of PB nanoparticles, which maintained excellent catalytic activity and stability after being recycled four times.

15.
Rev Sci Instrum ; 89(6): 064101, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29960580

RESUMO

A pulse chemisorption system combining a Tian-Calvet microcalorimeter (Setaram Sensys EVO 600) and an automated chemisorption apparatus (Micromeritics Autochem II 2920) was established to accurately measure differential adsorption heats of gas molecules' chemisorption on solid surfaces in a flow-pulse mode. Owing to high sensitivity and high degree of automation in a wide range of temperatures from -100 to 600 °C, this coupled system can present adsorption heats as a function of adsorption temperature and adsorbate coverage. The functions of this system were demonstrated by successful measurements of CO adsorption heats on Pd surfaces at various temperatures and also at different CO coverages by varying the CO concentration in the pulse dose. Key parameters, including adsorption amounts, integral adsorption heats, and differential adsorption heats of CO adsorption on a Pd/CeO2 catalyst, were acquired. Our adsorption-microcalorimetry system provides a powerful technique for the investigation of adsorption processes on powder catalysts.

16.
Nat Commun ; 9(1): 2533, 2018 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-29955067

RESUMO

Transition metal dichalcogenide materials have been explored extensively as catalysts to negotiate the hydrogen evolution reaction, but they often run at a large excess thermodynamic cost. Although activating strategies, such as defects and composition engineering, have led to remarkable activity gains, there remains the requirement for better performance that aims for real device applications. We report here a phosphorus-doping-induced phase transition from cubic to orthorhombic phases in CoSe2. It has been found that the achieved orthorhombic CoSe2 with appropriate phosphorus dopant (8 wt%) needs the lowest overpotential of 104 mV at 10 mA cm-2 in 1 M KOH, with onset potential as small as -31 mV. This catalyst demonstrates negligible activity decay after 20 h of operation. The striking catalysis performance can be attributed to the favorable electronic structure and local coordination environment created by this doping-induced structural phase transition strategy.

17.
Oral Oncol ; 80: 1-8, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29706183

RESUMO

OBJECTIVE: This study aimed to evaluate the efficacy and safety in locoregionally advanced nasopharyngeal carcinoma (NPC) patients receiving concurrent chemoradiotherapy (CCRT) plus Cetuximab (CTX) or Nimotuzumab (NTZ) compared to those receiving induction chemotherapy (IC) plus CCRT. MATERIALS AND METHODS: From January 2008 to December 2013, 715 eligible patients were enrolled in the study. Using propensity scores to adjust for gender, age, Karnofsky performance status (KPS), tumor stage, node stage, and clinical stage, a well-balanced cohort was created by matching each patient who received CTX/NTZ plus CCRT (137 patients) with two patients who underwent IC plus CCRT (274 patients). The primary endpoint was overall survival (OS), and other outcome variables included disease-free survival (DFS), distant metastasis-free survival (DMFS) and loco-regional relapse-free survival (LRRFS). RESULTS AND CONCLUSION: The median follow-up was 57.0 months and 55.0 months for the CTX/NTZ plus CCRT group and IC plus CCRT group, respectively. No significant differences were found between the CTX/NTZ plus CCRT group and the IC plus CCRT group in 3-year OS (95.5% vs. 94.7%, P = 0.083), 3-year DFS (93.3% vs. 86.1%, P = 0.104), 3-year DMFS (96.2% vs. 92.5%, P = 0.243) and 3-year LRRFS (97.0% vs. 95.1%, P = 0.297). Patients undergoing IC plus CCRT suffered from severe hematologic toxicity and diarrhea compared with those treated with CTX/NTZ plus CCRT. The combination of CTX/NTZ with CCRT is comparable to IC plus CCRT treatment in survival outcomes for locoregionally advanced NPC patients but has a better safety profile than IC plus CCRT treatment.

18.
Biol Pharm Bull ; 41(6): 885-890, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29618699

RESUMO

Six triterpenic acids were separated and purified from the ethyl acetate extractive fraction of ethanol extracts of Potentilla parvifolia FISCH. using a variety of chromatographic methods. The neuroprotective effects of these triterpenoids were investigated in the present study, in which the okadaic acid induced neurotoxicity in human neuroblastoma SH-SY5Y cells were used as an Alzheimer's disease cell model in vitro. The cell model was established with all trans-retinoic acid (5 µmol/L, 4 d) and okadaic acid (40 nmol/L, 6 h) treatments to induce tau phosphorylation and synaptic atrophy. Subsequently, the neuroprotective effects of these triterpenic acids were evaluated in vitro by this cell model. Results from the Western blot and morphology analysis suggested that compounds 3-6 had the better neuroprotective effects. Furthermore, we tested the level of mitochondrial reactive oxygen species and mitochondrial membrane potential of these compounds in SH-SY5Y cells by flow cytometry technology to investigate the potential neuroprotective mechanism of these compounds. All of the results indicated that maybe the mechanism of compounds 5 and 6 is to protect the cell from mitochondrial oxidative stress injuries.


Assuntos
Fármacos Neuroprotetores/farmacologia , Potentilla , Triterpenos/farmacologia , Doença de Alzheimer , Diferenciação Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Ácido Okadáico , Estresse Oxidativo/efeitos dos fármacos , Componentes Aéreos da Planta , Espécies Reativas de Oxigênio/metabolismo , Tretinoína
19.
Adv Mater ; 30(18): e1706617, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29575274

RESUMO

Electrochemical conversion of CO2 to value-added chemicals using renewable electricity provides a promising way to mitigate both global warming and the energy crisis. Here, a facile ion-adsorption strategy is reported to construct highly active graphene-based catalysts for CO2 reduction to CO. The isolated transition metal cyclam-like moieties formed upon ion adsorption are found to contribute to the observed improvements. Free from the conventional harsh pyrolysis and acid-leaching procedures, this solution-chemistry strategy is easy to scale up and of general applicability, thus paving a rational avenue for the design of high-efficiency catalysts for CO2 reduction and beyond.

20.
Phys Chem Chem Phys ; 20(14): 9659-9670, 2018 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-29582032

RESUMO

CeO2-Catalyzed C2H2 semihydrogenation reaction is a newly emerging catalytic reaction, but the reaction mechanism is not established. We herein report a comprehensive mechanistic study by in situ diffuse reflectance infrared Fourier transformed spectroscopy. Various types of surface species were observed to form upon C2H2 and C2H4 adsorption on CeO2 at different temperatures, including molecularly-adsorbed π-bonded and di-σ-bonded species, dissociatively-adsorbed species of C2H and C2H3, carbonates and formate species, and oligomers species, respectively. During the C2H2 semihydrogenation reaction, the CeO2 surface is partially reduced and strongly hydroxylated. Both O and Ce sites on CeO2 are capable of catalyzing C2H2 semihydrogenation reaction to C2H4, and the O site is more active than the Ce site. The reaction mechanism was elucidated with observed molecularly-adsorbed C2H2 species, a C2H3 intermediate and adsorbed C2H4 species on CeO2. The π-bonded C2H2 species at the O site was identified as the dominant active surface species for CeO2-catalyzed C2H2 semihydrogenation reaction. These results greatly advance the fundamental understanding of CeO2-catalyzed C2H2 semihydrogenation reaction.

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