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BACKGROUND: To review the changes and survey on status quo of the surgical treatment for esophageal cancer in China. The differences in diagnosis and treatment for esophageal cancer among hospitals in different regions across China were also investigated. METHODS: We sent questionnaires to 46 hospitals across China, investigating the volume of esophageal cancer surgeries, surgical procedures, and perioperative management under the guidance of esophageal surgery chiefs. RESULTS: A total of 46 questionnaires were sent out and collected. The survey results showed that in the past 5 years, the volume of surgeries for esophageal cancer remained stable by 23.9% of those hospitals, increased by 30.4%, and decreased by 45.7%. Of those patients treated by surgery, 19.1% were in the early stages, and 80.9% were in locally advanced stages. In terms of surgical procedures, 73.4% of the patients were treated by minimally invasive surgery and 85.7% of esophageal substitutes were a gastric conduit, 93.1% of the substitutes were pulled to the neck through the esophageal bed. For the lymph node dissection, 78.5% of the patients had a complete two-field lymph node dissection including the para-recurrent laryngeal nerve lymph nodes. Of the patients with neoadjuvant therapy, 53.5% received chemotherapy or chemotherapy plus immunotherapy (47.0%), and 43.5% had chemoradiation. CONCLUSIONS: Currently, in China, minimally invasive surgery-oriented multimodality treatment, including complete two-field lymph node dissection, has become the standard approach for esophageal cancer management. Over the past decade, this standardized approach has significantly improved prognosis compared to previous decades.
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Neoplasias Esofágicas , Humanos , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , China/epidemiologia , Inquéritos e Questionários , Masculino , Feminino , Esofagectomia/métodos , Esofagectomia/estatística & dados numéricosRESUMO
Solar-driven photothermal catalytic H2 production from lignocellulosic biomass was achieved by using 1T-2H MoS2 with tunable Lewis acidic sites as catalysts in an alkaline aqueous solution, in which the number of Lewis acidic sites derived from the exposed Mo edges of MoS2 was successfully regulated by both the formation of an edge-terminated 1T-2H phase structure and tunable layer number. Owing to the abundant Lewis acidic sites for the oxygenolysis of lignocellulosic biomass, the 1T-2H MoS2 catalyst shows high photothermal catalytic lignocellulosic biomass-to-H2 transformation performance in polar wood chips, bamboo, rice straw corncobs, and rice hull aqueous solutions, and the highest H2 generation rate and solar-to-H2 (STH) efficiency respectively achieves 3661 µmol·h-1·g-1 and 0.18% in the polar wood chip system under 300 W Xe lamp illumination. This study provides a sustainable and cost-effective method for the direct transformation of renewable lignocellulosic biomass to H2 fuel driven by solar energy.
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The development of stable, Earth-abundant, and high-activity molecular water oxidation catalysts under acidic and neutral conditions remains a great challenge. Here, the use of N-heterocyclic carbene (NHC)-based iron(III) complex 1 {[phenyl(tris(3-methylimidazol-1-ylidene))borate]2Fe(III)}+ as a catalyst for water oxidation under acidic and neutral conditions was investigated. Two iron(II) carbene complexes, 2 {[2,6-bis(3-methylimidazolium-1-yl)pyridine]2Fe}2+ and 3 {[2,6-bis(3-methylimidazolium-1-yl)pyridine-4-carboxylic acid]2Fe}2+, were also used for comparison. A series of experiments demonstrate that complex 1 has excellent performance in terms of both catalytic activity and stability. In addition, the faradaic efficiency and turnover frequency (TOF) reach 95.0% and 2.8 s-1, respectively. An overpotential of ca. 490 mV is obtained at pH 1.5. Density functional theory (DFT) calculations indicate that dehydrogenation is the potential-determining step (PDS) in water oxidation. Complex 1 has a lower free energy barrier in this process than 2 and 3. High-valent Fe species are further proven in 1 by spectroelectrochemical measurements, which are crucial in promoting water oxidation. This study is expected to contribute to the development of homogeneous water oxidation catalysis under acidic and neutral conditions.
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Two-dimensional (2D) semiconductors for photocatalysis are more advantageous than the other photocatalytic materials since the 2D semiconductors generally have large specific surface area and abundant active sites. Phosphorus silicon (SiP), with an indirect bandgap in bulk and a direct bandgap in the monolayer, has recently emerged as an attractive 2D material because of its anisotropic layered structure, tunable bandgap, and high charge carrier mobility. However, the utilization of SiP as a photocatalyst for photocatalysis has been scarcely studied experimentally. Herein, we reported the synthesis of SiP nanosheets (SiP NSs) prepared from bulk SiP by an ultrasound-assisted liquid-phase exfoliation approach which can act as a metal-free, efficient, and visible-light-responsive photocatalyst for photocatalytic H2 production and nitrogen fixation. In a half-reaction system, the maximal H2 and NH3 generation rate under visible light irradiation achieves 528 and 35 µmol·h-1·g-1, respectively. Additionally, the apparent quantum yield for H2 production at 420 nm reaches 3.56%. Furthermore, a Z-scheme photocatalytic overall water-splitting system was successfully constructed by using Pt-loaded SiP NSs as the H2-evolving photocatalyst, Co3O4/BiVO4 as the O2-evolving photocatalyst, and Co(bpy)33+/2+ as an electron mediator. Notably, the highest H2 and O2 generation rate with respect to Pt/SiP NSs achieves 71 and 31 µmol·h-1·g-1, respectively. This study explores the potential application of 2D SiP as a metal-free visible-light-responsive photocatalyst for photocatalysis.
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BACKGROUND: Alpha-L-fucosidase-1 (FUCA1) has been demonstrated to play opposing regulatory roles in adenocarcinoma and non-adenocarcinoma. Moreover, recent studies reported that FUCA1 could decrease the invasion capability by downregulating matrix metalloproteinase 9 (MMP-9) expression. However, the potential role and prognostic significance of FUCA1 in esophageal squamous cell carcinoma (ESCC) have not yet been explored. AIM: To evaluate the status, association, and prognostic value of FUCA1 and MMP-9 expression in ESCC. METHODS: Patients who underwent esophagectomy for ESCC between January 1, 2014, and December 31, 2014 at Sun Yat-Sen University Cancer Center were enrolled. The expression status of FUCA1 and MMP-9 in cancerous tissues was detected using immunohistochemistry. In addition, the expression profiles of the FUCA1 and MMP-9 genes in non-metastatic ESCC were extracted from The Cancer Genome Atlas (TCGA) database. RESULTS: High expression of FUCA1 and MMP-9 was found in 90 patients (75.6%) and 62 patients (52.1%), respectively. In the high FUCA1 expression group, the constituent ratios of patients with stage III disease (61.1% vs 37.9%, P = 0.029), lymphatic invasion (62.2% vs 31.0%, P = 0.003), and high MMP-9 expression (60.0% vs 27.6%, P = 0.002) were significantly higher than those in the low FUCA1 expression group. In Kaplan-Meier univariate analysis, advanced tumor-node-metastasis stage (III, P = 0.001), positive regional lymph node metastasis (N+, P = 0.002), high FUCA1 expression (P = 0.001), and high MMP-9 expression (P = 0.002) were potential predictors of shorter overall survival (OS), which was similar to the results analyzed based on the TCGA database. Further Cox multivariate regression analyses still demonstrated that FUCA1 and MMP-9 expression levels were independent prognostic factors of OS [hazard ratio (HR): 0.484, 95% confidence interval (CI): 0.239-0.979; P = 0.044; and HR: 0.591, 95%CI: 0.359-0.973, P = 0.039, respectively]. CONCLUSION: FUCA1 cooperation with MMP-9 may have a major role in affecting the ESCC invasion and metastatic capability, and serve as a valuable prognostic biomarker in ESCC.
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Herein, we present a stable water-soluble cobalt complex supported by a dianionic 2,2'-([2,2'-bipyridine]-6,6'-diyl)bis(propan-2-ol) ligand scaffold, which is a rare example of a high-oxidation species, as demonstrated by structural, spectroscopic and theoretical data. Electron paramagnetic resonance (EPR) spectroscopy and magnetic susceptibility measurements revealed that the CoIV center of the mononuclear complex in the solid state resides in the high spin state (sextet, S=5/2). The complex can effectively catalyze water oxidation via a single-site water nucleophilic attack pathway with an overpotential of only 360â mV in a phosphate buffer with a pH of 6. The key intermediate toward water oxidation was speculated based on theoretical calculations and was identified by in situ spectroelectrochemical experiments. The results are important regarding the accessibility of high-oxidation state metal species in synthetic models for achieving robust and reactive oxidation catalysis.
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Cobalto , Água , Catálise , Cobalto/química , Espectroscopia de Ressonância de Spin Eletrônica , Oxirredução , Água/químicaRESUMO
A Z-scheme system was successfully constructed for visible-light-driven photocatalytic H2 production from lignocelluloses, the highest H2 evolution rate of this Z-scheme system is 5.3 and 1.6 µmol h-1 in α-cellulose and poplar wood chip aqueous solutions, respectively, under visible light irradiation.
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As an alternative strategy for H2 production under ambient conditions, solar-driven lignocellulose-to-H2 conversion provides a very attractive approach to store and utilize solar energy sustainably. Exploiting efficient photocatalyst for photocatalytic lignocellulose-to-H2 conversion is of huge significance and remains the key challenge for development of solar H2 generation from lignocellulose. Herein, 2D-2D MoS2 /TiO2 photocatalysts with large 2D nanojunction were constructed for photocatalytic lignocellulose-to-H2 conversion. In this smart structure, the 2D nanojunctions acted as efficient channel for charge transfer from TiO2 to MoS2 to improve charge separation efficiency and thus enhance photocatalytic lignocellulose-to-H2 conversion activity. The 2 % MoS2 /TiO2 photocatalyst showed the highest photocatalytic lignocellulose-to-H2 conversion performance with the maximal H2 generation rate of 201 and 21.4â µmol h-1 g-1 in α-cellulose and poplar wood chip aqueous solution, respectively. The apparent quantum yield at 380â nm reached 1.45 % for 2 % 2D-2D TiO2 /MoS2 photocatalyst in α-cellulose aqueous solution. This work highlights the importance of optimizing the interface structures of photocatalyst for solar-driven lignocellulose-to-H2 conversion.
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OBJECTIVE: To explore the mechanism of miR-195-5p in the pathogenesis non-small cell lung cancer (NSCLC) and cisplatin resistance. METHODS: The function of miR-195-5p in NSCLC and cisplatin resistance were determined by MTT, scratch assay, transwell assay, and nude mice xenograft experiments. miR-195-5p target gene was identified by dual-luciferase reporter assays and real-time PCR analysis. RESULTS: miR-195-5p content was lower in A549/DDP than that in A549 cells, with reduced chemotherapy sensitivity and increased cell invasion and migration ability. The loss-of-function and gain-of-function assays illustrated that miR-195-5p might have increased the chemosensitivity to cisplatin in the A549/DDP cells and decreased cell migration and invasion. FGF2 is a negatively correlated action target of miR-195-5p. miR-195-5p might affect EMT by inhibiting FGF2. Overexpression of FGF2 resulted in enhanced cisplatin resistance in the cells, while miR-195-5p might have reversed this resistance. CONCLUSION: Overall, miR-195-5p might target FGF2 to reduce cisplatin resistance in A549/DDP cells and enhance chemosensitivity.
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BACKGROUND: The impact of neoadjuvant chemoradiotherapy (nCRT) on early stage esophageal cancer is unknown. Here, we compared the outcomes after esophagectomy alone or nCRT plus surgery for clinically staged node-negative esophageal cancer. METHODS: We searched the Surveillance, Epidemiology, and End Results database for patients with clinically node-negative (cN0) esophageal cancer from 2004 to 2016 who underwent surgery alone or nCRT plus surgery. Propensity score matching and Cox regression analysis were used to identify covariates associated with overall survival and cancer-specific survival. RESULTS: A total of 1587 patients were retrospectively identified, of whom 49.8% (n = 791) received nCRT and 80.2% (n = 1273) were truly node-negative diseases. For the entire cohort, surgery alone was associated with a statistically significant but modest absolute increase in survival outcomes (P < 0.01). After matching, nCRT was associated with improved five-year overall survival for pT3-4N0 (localized) disease (59.6% vs. 37.7%; P < 0.001) and pathological node-positive disease (60.5% vs. 40.7%; P = 0.002). Cox multivariate regression analysis revealed that the addition of nCRT for truly node-negative patients with tumor length ≥ 3 cm, pT1-2N0 (early-staged) and localized disease were independent risk factors for survival than surgery alone (P < 0.01). CONCLUSIONS: Compared with surgery alone, patients with cN0 esophageal cancer with pathological node-positive or localized true node-negative disease gain a significant survival benefit from nCRT. However, nCRT plus surgery was associated with decreased survival for early-staged true node-negative patients. This finding may have significant implications on the use of neoadjuvant chemoradiation in patients with cN0 disease.
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Quimiorradioterapia/métodos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Terapia Neoadjuvante/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Programa de SEERRESUMO
BACKGROUND: This study investigated the prognostic impact of (neo-)adjuvant radiation therapies in early stage esophageal cancer. METHODS: A retrospective analysis using the Surveillance, Epidemiology, and End Results (SEER) database was conducted from 2004 to 2016. Patients with pathologically staged T1-4N0M0 esophageal cancer were divided into two treatment groups: (i) neoadjuvant radiotherapy followed by surgery; and (ii) upfront esophagectomy followed by adjuvant radiotherapy. Propensity scored match and Cox proportional hazards model were used to identify covariates associated with overall survival and cancer-specific survival. RESULTS: There were 821 patients selected, of whom 588 (71.6%) received neoadjuvant radiotherapy and 233 (28.4%) received adjuvant radiotherapy. For the entire cohort, neoadjuvant radiotherapy was associated with a significantly benefit in five-year survival outcomes compared with adjuvant radiotherapy (P < 0.01). After matching, the survival outcomes were still better for neoadjuvant radiotherapy than that of adjuvant treatment. Stratifying based on pathologic tumor status, neoadjuvant radiation was associated with improved CSS (five-year survival 73.7% vs. 42.1%; P = 0.014) for localized (pT3-4N0) disease. The Cox multivariate regression analysis revealed that the addition of neoadjuvant radiation for pT3-4N0 diseases with tumor length ≥ 5 cm and squamous cell carcinoma, was a powerful prognostic factor for improved cancer-specific survival (P < 0.01). CONCLUSIONS: Compared with adjuvant radiotherapy, the addition of neoadjuvant radiation for pT3-4N0 diseases has been associated with improved cancer-specific survival in high-risk patients. Studies on preoperative neoadjuvant therapies would be plausible in high-risk esophageal cancer patients.
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Neoplasias Esofágicas/radioterapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos RetrospectivosRESUMO
Exploiting an appropriate strategy to prepare fine crystal quality black phosphorus nanosheet (BPNS) catalyst is a major challenge for its practical application in catalysis. Herein, we address this challenge by developing a rapid electrochemical expansion strategy for scale preparation of fine crystal quality BPNSs from bulk black phosphorus, which was demonstrated to be an active cocatalyst for photocatalytic nitrogen fixation in the presence of CdS as a photocatalyst. The transient photocurrent and charge density studies show that the BPNSs can efficiently accelerate charge separation of CdS, leading to the enhanced photocatalytic activities of BPNS/CdS nanocomposites for nitrogen fixation. The 1.5% BPNS/CdS photocatalyst exhibits the highest photocatalytic activity for nitrogen fixation with an NH3 evolution rate of 57.64 µmol·L-1·h-1. This study not only affords a rapid and simple strategy for scale synthesis of fine crystal quality BPNSs but also provides new insights into the design and development of black phosphorus-based materials as low-cost metal-free cocatalysts for photocatalytic nitrogen fixation.
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BACKGROUND: After neoadjuvant chemoradiotherapy (nCRT) for esophageal cancer, high pathologically complete response (pCR) rates are being achieved especially in patients with squamous cell carcinoma (SCC). An active surveillance strategy has been proposed for SCC patients with clinically complete response (cCR) after nCRT. To justify omitting surgical resection, patients with residual disease should be accurately identified. The aim of this study is to assess the accuracy of response evaluations after nCRT based on the preSANO trial, including positron emission tomography with computed tomography (PET-CT), endoscopy with bite-on-bite biopsies and endoscopic ultrasonography (EUS) with fine-needle aspiration (FNA) in patients with potentially curable esophageal SCC. METHODS: Operable esophageal SCC patients who are planned to undergo nCRT according to the CROSS regimen and are planned to undergo surgery will be recruited from four Asian centers. Four to 6 weeks after completion of nCRT, patients will undergo a first clinical response evaluation (CRE-1) consisting of endoscopy with bite-on-bite biopsies. In patients without histological evidence of residual tumor (i.e. without positive biopsies), surgery will be postponed another 6 weeks. A second clinical response evaluation (CRE-2) will be performed 10-12 weeks after completion of nCRT, consisting of PET-CT, endoscopy with bite-on-bite biopsies and EUS with FNA. Immediately after CRE-2 all patients without evidence of distant metastases will undergo esophagectomy. Results of CRE-1 and CRE-2 as well as results of the three single diagnostic modalities will be correlated to pathological response in the resection specimen (gold standard) for calculation of sensitivity, specificity, negative predictive value and positive predictive value. DISCUSSION: If the current study shows that major locoregional residual disease (> 10% residual carcinoma or any residual nodal disease) can be accurately (i.e. with sensitivity of 80.5%) detected in patients with esophageal SCC, a prospective trial will be conducted comparing active surveillance with standard esophagectomy in patients with a clinically complete response after nCRT (SINO trial). TRIAL REGISTRATION: The preSINO trial has been registered at ClinicalTrials.gov as NCT03937362 (May 3, 2019).
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Quimiorradioterapia/métodos , Confiabilidade dos Dados , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/terapia , Terapia Neoadjuvante/métodos , Biópsia por Agulha Fina , Endoscopia/métodos , Endossonografia/métodos , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Esofagectomia , Esôfago/patologia , Humanos , Neoplasia Residual , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND: The impact of adjuvant treatment for esophageal carcinoma with tumor-negative lymph nodes after upfront radical esophagectomy is still uncertain. This study investigated the effects of postoperative radiotherapy in pT1-3N0 esophageal carcinoma after radical resection. METHOD: We retrospectively identified pT1-3N0M0 esophageal carcinoma patients between 2000 and 2016 from the Surveillance, Epidemiology, and End Results database. Patients with upfront esophagectomy were categorized as having received surgery alone (SA) and surgical resection followed by adjuvant radiotherapy (SA + RT). Propensity score matching, univariate and multivariate analysis were performed to compare overall survival (OS) and cause-specific survival (CSS). RESULTS: A total of 2862 patients were identified, of whom 274 received SA + RT and 2588 received SA. The median follow-up was 60.4 months (95%CI, 58.7-62.1 months). The five-year OS and CSS were better for SA group compared with SA + RT group (P < 0.001, respectively). Furthermore, after matching, the OS and CSS were still significantly better for SA patients. For T subgroup analysis, postoperative radiotherapy was an independent prognostic factor only for pT1 patients with worse OS, without survival differences for pT2 and pT3 patients. However, after multivariate cox analysis, postoperative radiotherapy can provide significantly better OS for pT3 patients with tumor length ≥5 cm (P = 0.03; 95%CI, 0.29-0.94). CONCLUSIONS: Among pT1-3N0M0 esophageal carcinoma patients, postoperative radiotherapy can provide significantly better OS for pT3 patients with tumor length ≥5 cm. However, there are no survival benefits for pT1-2 patients after SA + RT procedure. This finding may have significant implications on the use of adjuvant radiation in patients with pN0 disease.
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Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas do Esôfago/radioterapia , Radioterapia Adjuvante/mortalidade , Idoso , China/epidemiologia , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/epidemiologia , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Prognóstico , Pontuação de Propensão , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Two remarkable polyoxometalate-bridged Cu(I)- and Ag(I)-thiacalix[4]arene dimers, namely, [Cu4(SiW12O40)(L)2(DMF)2]·2EtOH·DMF (1-Cu) and [Ag4(PMo12O40)(L)2]·OH (1-Ag), were prepared by using a new thiacalix[4]arene, metal cation and polyoxometalate (L = tetra[2-(ethylthio)-1-methyl-1H-imidazole]-thiacalix[4]arene). In 1-Cu and 1-Ag, two thiacalix[4]arenes were linked together by one [SiW12O40]4- or [PMo12O40]3- anion via two metal cations to give a molecular dimer. Further, adjacent dimers were extended into a high-dimensional supramolecular architecture through hydrogen bonds. Markedly, these molecular dimers are exceedingly stable in organic solvents and then were employed as efficient catalysts for catalytic oxidation desulfurization as well as the azide-alkyne "click" reaction.
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BACKGROUND: In this retrospective study, we evaluated the safety and efficacy of video-assisted thoracic surgery (VATS) sleeve lobectomy for patients with centrally located non-small cell lung cancer. METHODS: All consecutive patients who received VATS sleeve lobectomy (n = 54) and thoracotomy sleeve lobectomy (n = 94) were analyzed retrospectively; after propensity score matching, 78 paired cases were selected for further statistical analysis. RESULTS: Among all patients, the VATS group showed significantly better recurrence-free survival and overall survival than the thoracotomy group (P = .025 and P = .026, respectively) with smaller total tumor size and earlier pathological tumor-node-metastasis (TNM) stage. Nevertheless, after matching, the recurrence-free survival (50.9% vs 48.7%; P = .445) and overall survival (79.5% vs 66.7%; P = .198) were not significantly different. There was significantly less blood loss (228 vs 246 mL; P = .022), shorter thoracic drainage stay (4.6 vs 6.8 days; P < .001), and postoperative hospital stay (9.2 vs 11.3 days; P = .033) in the VATS group. Multivariate Cox analyses demonstrated that the surgical procedure was not an independent prognostic factor for recurrence-free survival, not only for patients with an invasive component size of 3 cm or less and negative lymphatic invasion, but for locally advanced patients with an invasive tumor size >3 cm (hazard ratio: 0.94; 95% confidence interval: 0.36-2.45; P = .55) or positive lymphatic invasion (hazard ratio: 0.91; 95% confidence interval: 0.35-2.39; P = .41). CONCLUSIONS: VATS sleeve lobectomy is a safe and effective procedure associated with better postoperative recovery and equivalent oncological results, even for locally advanced non-small cell lung cancer patients with an invasive tumor size larger than 3 cm or accompanying lymphatic invasion.
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Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Pneumonectomia/métodos , Pontuação de Propensão , Cirurgia Torácica Vídeoassistida/métodos , Toracotomia/métodos , Brônquios , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
A supramolecular complex, [Au(C^N^C)(C≡CC6 H4 C≡C)Pt(terpy)]+ , has been synthesized as a photocatalyst for water reduction. This compound consists of a cyclometalated alkyne-gold(III) photosensitizer and a platinum(II) terpyridine complex bridged through a central phenylethynyl group.
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The development of novel iridium(III) complexes has continued as an important area of research owing to their highly tunable photophysical properties and versatile applications. In this report, three heteroleptic dimesitylboron-containing iridium(III) complexes, [Ir(p-B-ppy)2 (N^N)]+ {p-B-ppy=2-(4-dimesitylborylphenyl)pyridine; N^N=dipyrido[3,2-a:2',3'-c]phenazine (dppz) (1), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq) (2), and 1,10-phenanthroline (phen) (3)}, were prepared and fully characterized electrochemically, photophysically, and computationally. Altering the conjugated length of the N^N ligands allowed us to tailor the photophysical properties of these complexes, especially their luminescence wavelength, which could be adjusted from λ=583 to 631â nm in CH2 Cl2 . All three complexes were evaluated as visible-light-absorbing sensitizers for the photogeneration of hydrogen from water and as photocatalysts for the photopolymerization of methyl methacrylate. The results showed that all of them were active in both photochemical reactions. High activity for the photosensitizer (over 1158â turnover numbers with 1) was observed, and the system generated hydrogen even after 20â h. Additionally, poly(methyl methacrylate) with a relatively narrow molecular-weight distribution was obtained if an initiator (i.e., ethyl α-bromophenylacetate) was used. The living character of the photoinduced polymerization was confirmed on the basis of successful chain-extension experiments.
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Expanding the photoresponse range of TiO2-based photocatalysts is of great interest for photocatalytic H2 production. Herein, noble-metal-free CuInS2 quantum dots were employed as a novel inorganic dye to expand the visible light absorption of TiO2/MoS2 for solar H2 generation. The as-prepared CuInS2/TiO2/MoS2 photocatalysts exhibit broad absorption from the ultraviolet to near-infrared region. Under visible light irradiation (λ > 420 nm), the CuInS2/TiO2/MoS2 photocatalyst with 0.6 mmol g-1 CuInS2 and 0.5 wt% MoS2 showed the highest H2 evolution rate with a value of 1034 µmol h-1 g-1. Moreover, a considerable H2 evolution rate of 141 µmol h-1 g-1 was obtained under the irradiation of the optimized CuInS2/TiO2/MoS2 photocatalyst with >500 nm light. The reaction mechanism of the CuInS2/TiO2/MoS2 photocatalyst for photocatalytic H2 evolution was investigated in detail by photoluminescence decay study, and the results showed that the photoexcited electrons of CuInS2 can be transferred efficiently through TiO2 to MoS2 and then react with the absorbed protons to generate H2. The reported sensitization strategy tremendously improves the visible light absorption capacity and the photocatalytic performance of TiO2-based photocatalysts.
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OBJECTIVE: To evaluate the prevalence, pattern and risk factors of lymph node metastasis (LNM) for pathological T1 (pT1) esophageal cancer (EC). METHODS: The clinical data of 143 cases of pT1 patients who underwent esophagectomy and lymph node dissection during January 2011 and July 2016 were reviewed, including 120 male patients and 23 female patients with a median age of 60 years. The pattern of LNM was analyzed and the risk factors related to LNM were assessed by logistic regression analysis. The nomogram model was used to estimate the individual risk of lymph node metastasis. RESULTS: Of 143 patients with T1 tumors, 25 patients had LNM, and the LNM rate was 17.5%. The LNM rate was 8.0% for T1a tumors, and 22.5% for T1b tumors. The logistic regression analysis showed that the depth of tumor infiltration (P < 0.05), tumor size (P < 0.01), tumor location (P < 0.05), and tumor differentiation (P < 0.01) were independent risk factors related to LNM for T1 EC. These four parameters allowed the compilation of a nomogram to estimate the individual risk of LNM. Tumor differentiation (P < 0.05) was an independent risk factor related to LNM for T1a tumors, and tumor size (P < 0.05) and tumor location (P < 0.05) were independent risk factors related to LNM for T1b tumors. Of 25 patients with LNM, one patient had cervical LNM, 15 patients with thoracic LNM, and 17 patients with abdominal LNM. The relatively highest LNM sites were laryngeal recurrent nerve (n = 8), the left gastric artery (n = 8), right and left cardiac (n = 6) and thoracic paraesophageal (n = 5). CONCLUSIONS: T1 EC has a relatively high LNM rate, and the depth of tumor infiltration, tumor size, tumor location and tumor differentiation are correlated with LNM. The LNM risk and extent must be considered comprehensively in decision-making of a better surgical treatment and lymph node dissection strategy.