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1.
JACS Au ; 3(11): 3213-3226, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38034962

RESUMO

Zeolite-encapsulated subnanometer metal catalysts are an emerging class of solid catalysts with superior performances in comparison to metal catalysts supported on open-structure solid carriers. Currently, there is no general synthesis methodology for the encapsulation of subnanometer metal catalysts in different zeolite structures. In this work, we will show a general synthesis method for the encapsulation of subnanometer metal clusters (Pt, Pd, and Rh) within various silicoaluminate zeolites with different topologies (MFI, CHA, TON, MOR). The successful generation of subnanometer metal species in silicoaluminate zeolites relies on the introduction of Sn, which can suppress the migration of subnanometer metal species during high-temperature oxidation-reduction treatments according to advanced electron microscopy and spectroscopy characterizations. The advantage of encapsulated subnanometer Pt catalysts in silicoaluminate zeolites is reflected in the direct coupling of ethane and benzene for production of ethylbenzene, in which the Pt and the acid sites work in a synergistic way.

2.
Angew Chem Int Ed Engl ; 62(36): e202308523, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37370248

RESUMO

Constructing a powerful photocatalytic system that can achieve the carbon dioxide (CO2 ) reduction half-reaction and the water (H2 O) oxidation half-reaction simultaneously is a very challenging but meaningful task. Herein, a porous material with a crystalline topological network, named viCOF-bpy-Re, was rationally synthesized by incorporating rhenium complexes as reductive sites and triazine ring structures as oxidative sites via robust -C=C- bond linkages. The charge-separation ability of viCOF-bpy-Re is promoted by low polarized π-bridges between rhenium complexes and triazine ring units, and the efficient charge-separation enables the photogenerated electron-hole pairs, followed by an intramolecular charge-transfer process, to form photogenerated electrons involved in CO2 reduction and photogenerated holes that participate in H2 O oxidation simultaneously. The viCOF-bpy-Re shows the highest catalytic photocatalytic carbon monoxide (CO) production rate (190.6 µmol g-1 h-1 with about 100 % selectivity) and oxygen (O2 ) evolution (90.2 µmol g-1 h-1 ) among all the porous catalysts in CO2 reduction with H2 O as sacrificial agents. Therefore, a powerful photocatalytic system was successfully achieved, and this catalytic system exhibited excellent stability in the catalysis process for 50 hours. The structure-function relationship was confirmed by femtosecond transient absorption spectroscopy and density functional theory calculations.

3.
Semin Thorac Cardiovasc Surg ; 35(3): 583-593, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35550846

RESUMO

We aimed to evaluate the prognostic value of visceral pleural invasion on the survival of node-negative non-small cell lung cancer ≤3 cm using a large cohort. The Kaplan-Meier method was used to compare overall survival (OS); competing risk analysis with Fine-Gray's test was used to compare cancer- specific survival between groups. The least absolute shrinkage and selection operator penalized Cox regression model was used to identify prognostic factors. In total, 9725 eligible cases were included in this study, and they were separated into 3 groups: tumor invasion beneath the elastic layer (PL0), 8837 cases; tumor invasion surpassing the elastic layer (PL1), 505 cases; and tumor invasion to the visceral pleural surface (PL2), 383 cases. Visceral pleural invasion was more likely to occur in poorly differentiated and larger-sized tumors. Survival curves displayed that PL0 conferred better survival rates than PL1 and PL2, and PL1 achieved outcomes equivalent to those of PL2. Tumor size and histology subset analyses further corroborated this conclusion. Least absolute shrinkage and selection operator -penalized Cox regression analysis confirmed that PL status was an independent prognostic factor for both OS and cancer- specific survival. This study supported the notion that in node-negative non-small cell lung cancer ≤3 cm, PL1 patients should remain classified as pT2a, which could improve staging accuracy.

4.
J Cancer Res Clin Oncol ; 149(5): 1777-1784, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35729353

RESUMO

PURPOSE: Controversy exists with regard to the T category of non-small cell lung cancer (NSCLC) with adjacent lobe invasion (ALI), and dispute arises on assigning this subset into T2 or T3 category. We evaluated the effect of ALI on the survival of resected NSCLC ≤ 5 cm, with purpose of determining the most appropriate T category for this population. METHODS: The entire cohort was divided into three subgroups (ALI group, T2 group and T3 group). Kaplan-Meier with log-rank method was carried out to compare overall survival (OS) differences. Propensity score matching (PSM) was performed to minimize bias. RESULTS: A total of 12,564 eligible NSCLC cases (ALI group: 114 cases; T2 group: 10,046 cases; T3 group: 2404 cases) were included in this study. The incidence of ALI was about 0.9%. Before PSM, survival analyses demonstrated that no significant OS differences were observed between ALI group and T2 group, and between ALI group and T3 group, neither in the entire cohort analysis nor in the subgroup analysis. After PSM, there were 102 pairs and 98 pairs in the ALI and T2 matching group and ALI and T3 matching group, respectively. In the matched cohorts, survival curves showed that the OS of ALI group was comparable to that of T2 group (P = 0.950), but superior to that of T3 group (P = 0.012). CONCLUSIONS: The current study proposed that NSCLC with ALI ≤ 5 cm should be still categorized as T2 category, which could improve staging accuracy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Pneumonectomia , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos
5.
Lipids Health Dis ; 21(1): 129, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463190

RESUMO

BACKGROUND: Little is known about the link between the monocyte to high-density lipoprotein cholesterol ratio (MHR) and frequent premature ventricular complexes (PVCs). This investigation aimed to evaluate the link between the MHR and frequent PVCs in patients, as well as their outcomes, using the axis, burden, coupling interval-ventricular tachycardia (ABC-VT) risk score (ARS). METHODS: Two hundred patients with frequent PVCs and 70 controls were retrospectively enrolled, and their general data were gathered. The MHR and ARS were calculated. Then, patients developing frequent PVCs were classified into a medium-/high-risk subgroup and a low-risk subgroup according to ARS. The results were evaluated employing comparative statistical analyses, Spearman's correlation, logistic regression analyses, and receiver operating characteristic (ROC) curves. RESULTS: The MHR in the controls was obviously lower than that in the frequent PVC group. In addition, the MHR was the lowest in the control group and highest in the medium-/high-risk subgroup, with that of the low-risk subgroup falling in the middle. Spearman's correlation analyses showed that the MHR was positively correlated with the ARS (ρ = 0.307, P < 0.001). Ultimately, the MHR was found to be a risk factor for frequent PVCs in the multivariate analysis. In addition, an MHR cutoff point of 254.6 featured 67.50% sensitivity and 67.14% specificity for predicting frequent PVCs, and the area under the curve (AUC) reached 0.694 (95% confidence interval: 0.623-0.766) (P < 0.001). CONCLUSIONS: The MHR is positively and independently correlated with frequent PVCs and can be used as a practical, cost-saving and simple biomarker of inflammation owing to its value in predicting frequent PVCs. In addition, the MHR is crucial to risk stratification and prognosis, which may give it clinical value in the prevention and management of frequent PVCs.


Assuntos
Monócitos , Humanos , HDL-Colesterol , Estudos Retrospectivos , Fatores de Risco , Área Sob a Curva
6.
Semin Thorac Cardiovasc Surg ; 34(3): 1040-1048, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34216749

RESUMO

We identified the prognostic factors of resected stage IA non-small cell lung cancer (NSCLC) and developed a nomogram, with purpose of defining the high-risk population who may need closer follow-up or more intensive care. Eligible stage IA NSCLC cases from the Surveillance, Epidemiology, and End Results (SEER) database and the Sun Yat-sen University Cancer Center (SYSUCC) were included. Stage IB NSCLCs were also included for evaluating the risk stratification efficacy. Cancer specific survival (CSS) was compared between groups. Statistically significant factors from multivariate analysis were entered into the nomogram. The performance of the nomogram was evaluated by concordance index (C-index) and calibration plots. A total of 23,112 NSCLC cases (SEER stage IA training cohort, N=7,777; SEER stage IA validation cohort, N=7,776; SEER stage IB cohort, N=7,559) from the SEER database were included. 1,304 NSCLC cases (SYSUCC stage IA validation cohort, N=684; SYSUCC stage IB cohort, N=620) from the SYSUCC were also included. Younger age, female, lobectomy, well differentiated, smaller size and more examined lymph nodes were identified as favorable prognostic factors. A nomogram was established. The C-index was 0.68 (95%CI, 0.67-0.69), 0.66 (95% CI, 0.64-0.68) and 0.66 (95% CI, 0.61-0.71) for the SEER training cohort, SEER validation cohort and SYSUCC validation cohort. A risk classification system was constructed to stratify stage IA NSCLC into low-risk subgroup and high-risk subgroup. The CSS curves of these two subgroups showed statistically significant distinctions. This nomogram delivered a prognostic prediction for stage IA NSCLC and may aid individual clinical practice.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Feminino , Humanos , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Nomogramas , Programa de SEER , Resultado do Tratamento
7.
Front Surg ; 8: 757085, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778364

RESUMO

Background: The current study analyzed resected stage I-IIIA pulmonary lymphoepithelioma-like carcinoma (LELC) cases to define the clinical characteristics, prognosis and long-term outcomes of resected LELC, with the purpose of guiding clinical management for this rare tumor. Methods: Resected stage I-IIIA LELC, adenocarcinoma (ADC) and squamous cell carcinoma (SCC) cases from our center were enrolled. Propensity score matching (PSM) was applied to minimize the selection bias. Overall survival (OS) and disease-free survival (DFS) were compared between groups. Multivariate analyses were performed to identify the prognostic factors, and a nomogram was developed. Results: A total of 159 LELCs, 2,757 ADCs, and 1,331 SCCs were included. LELC, dominated among younger patients and non-smokers. LELC was a poorly differentiated disease that lacked driver gene mutations and was positive for immunohistochemistry indicators of squamous cell lineage. Survival analyses revealed that OS was significantly better for LELC than for other common non-small cell lung cancers (NSCLCs) both before PSM (all P < 0.001) and after PSM (all P < 0.05). Further analyses revealed that early pathological node stage and preoperative albumin level ≥35 were identified as independent prognostic factors favoring OS and DFS. Conclusions: LELC, dominated among younger and non-smoking populations, lacked driver gene mutations and was positive for immunohistochemistry indicators of squamous cell lineage. The survival outcome of LELC was better than other common NSCLCs.

8.
Lung Cancer ; 159: 135-144, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34340110

RESUMO

OBJECTIVES: To compare the perioperative and oncologic outcomes following pneumonectomy performed by uniportal video-assisted thoracoscopic surgery (U-VATS) and thoracotomy in patients with centrally located non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: Patients with NSCLC who underwent pneumonectomy at the Shanghai Pulmonary Hospital (SPH) and Sun Yat-sen University Cancer Center (SYUCC) with the U-VATS approach or open approach between 2011 and 2016 were selected. Propensity score matching (1:3) was performed to balance the baseline covariates. Overall survival (OS) rates and recurrence-free survival (RFS) rates were estimated and compared using the Kaplan-Meier method, respectively. RESULTS: The enrollees in the study were 579 patients in the SPH cohort, with 501 (86.5%) in the open group and 48 (13.5%) in the U-VATS group, and 271 patients in the SYUCC cohort, with 245 (90.4%) in the open group and 26 (9.6%) in the U-VATS group. After propensity score matching, morbidity rates and 30-day mortality rates were found to be similar between the U-VATS group and open group in both the SPH and SYUCC cohorts. The long-term OS rate of patients who underwent U-VATS pneumonectomy did not significantly differ compared with the patients who underwent open pneumonectomy in both cohorts (SPH, p = .900; SYUCC, p = .240). Cox regression analysis revealed that the surgical option was not a risk factor for the OS rate (SPH: hazard ratio [HR], 0.925; 95% confidence interval [CI], 0.555 to 1.542; SYUCC: HR, 1.524; 95% CI, 0.752 to 3.087). CONCLUSION: U-VATS can be used to safely perform pneumonectomy in patients with centrally located NSCLC without compromising the perioperative and oncologic outcomes compared with an open approach.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/cirurgia , China/epidemiologia , Humanos , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Pontuação de Propensão , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida , Toracotomia , Resultado do Tratamento
9.
Ann Transl Med ; 9(12): 980, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34277780

RESUMO

BACKGROUND: Defecation delay (greater than or equal to 3 days post-surgery) is a common symptom in patients after lung tumor surgery. This study investigated the incidence and relevant risk factors of defecation delay in patients after lung tumor surgery. METHODS: Between October 2019 and March 2020, a prospective nested case-control study was conducted in 80 patients who received lung tumor surgery in the Department of Thoracic Surgery at the Sun Yat-sen University Cancer Center. According to the Rome III criteria for functional constipation and the accepted definitions in the literature, patients with defecation delay time greater than or equal to 3 days post-surgery were classified as the defecation delay group, and the remaining patients were considered the control group. A questionnaire survey was conducted to explore the trait of the stool, defecation time, postoperative activity, diet, and perioperative pain score. Statistical analyses were performed to compare the risk factors affecting defecation time in the two groups. RESULTS: Out of 80 patients, a total of 44 patients (44/80) experienced defecation delay after the operation. Univariate analysis showed that there were significant differences between the two groups in operation methods (P<0.029), postoperative stool trait (P<0.001), difficulty in defecation (P<0.01), and perioperative pain score (P=0.0178), suggesting that change of stool characteristics and pain were possible factors causing defecation delay. Multivariate analysis also revealed significant differences between the two groups in the postoperative pain score on the first day post-surgery (P=0.03). CONCLUSIONS: Defecation delay is a common symptom in patients after lung cancer surgery, and is related to operation method, pain score, and changes in stool characteristics. This study identified that minimally invasive surgery, postoperative pain relief treatment, and health education may play an important role in preventing delayed defecation.

10.
J Thorac Dis ; 13(4): 2363-2377, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34012585

RESUMO

BACKGROUND: According to the National Comprehensive Cancer Network (NCCN) guidelines, surveillance or adjuvant chemoradiation is recommended for patients with completely resected pT2-4aN0M0 esophageal carcinoma (EC). Due to this population's variant prognosis, we developed novel nomograms to define the high-risk patients who may need closer follow-up or even post-operative therapy. METHODS: Cases with resected pT2-4aN0M0 EC from the Surveillance, Epidemiology, and End Results (SEER) database and the Sun Yat-sen University Cancer Center (SYSUCC) were enrolled in the study. The SEER database cases were randomly assigned into the training cohort (SEER-T) and the internal validation cohort (SEER-V). Cases from the SYSUCC served as the external validation cohort (SYSUCC-V). Overall survival (OS) and cancer specific survival (CSS) were compared between groups. Multivariate analyses were applied to identify the prognostic factors. Nomograms and risk-classifying systems were developed. The nomograms' performances were evaluated by concordance index (C-index), calibration plots and decision curve analysis (DCA). RESULTS: A total of 2,441 eligible EC cases (SEER-T, n=839; SEER-V, n=279; SYSUCC-V, n=1,323) were included. Age, sex, chemotherapy, lymph node harvested (LNH) and T stage were identified as the independent predictors for CSS. Regarding OS, it also included the prognostic factor of histology. Nomograms were formulated. For CSS, the C-index was 0.68 [95% confidence interval (CI): 0.66-0.71], 0.67 (95% CI: 0.63-0.71) and 0.61 (95% CI: 0.59-0.63) for the SEER-T, SEER-V, and SYSUCC-V, respectively. For OS, the C-index was 0.69 (95% CI: 0.66-0.72), 0.64 (95% CI: 0.59-0.69) and 0.62 (95% CI: 0.61-0.63) for the SEER-T, SEER-V, and SYSUCC-V, respectively. The calibration curves and DCA showed good performances of the nomograms. In further analyses, risk-classification systems stratified pT2-4aN0M0 EC into low-risk and high-risk subgroup. The OS and CSS curves of these 2 subgroups, in the full analysis set or stratified by TNM stage, histology, T stage and LNH categories, showed significant distinctions. CONCLUSIONS: The novel prognostic nomograms and risk-stratifying systems which separated resected pT2-4aN0M0 esophageal carcinoma patients into the low-risk and high-risk prognostic groups were developed. It may help clinicians estimate individual survival and develop individualized treatment strategies.

11.
Bioresour Technol ; 321: 124443, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33276209

RESUMO

Non-noble bimetallic nanoparticles anchored on Zeolitic Imidazolate Frameworks, bifunctional ReMo@ZNB catalyst, has been demonstrated to promote Kraft lignin depolymerization. In this study, the catalytic activities under different heat treatment conditions are ranked as follows: ReMo@ZNB-700 (Air) > ReMo@ZNB-500 (Air) > ReMo@ZNB-700 (N2). Particularly, bimetallic ReMo nanocatalyst with Re/Mo atomic ratio of 1/3 shows superior performance. Excellent yields of Ethyl acetate soluble products (92.18%) and Petroleum ether extracted biofuels (78%) are obtained at 300℃ and 24 h, and the calorific value is 32.33 MJ/kg. The ReMo@ZNB catalyst exhibits superior recyclability and regeneration after cycle experiment. Structural characterization results reveal that the incorporation of ReMo can engender the transformation of lattice morphology, the strength of hydrogenation and acid adsorption. The possible mechanism is based on the synergism of adsorption coupling and hydrogenation over ReMo@ZNB catalyst. The synergic action initiates potential perspectives for improving lignin hydroconversion.


Assuntos
Rênio , Zeolitas , Biocombustíveis , Lignina , Molibdênio
12.
Pathol Res Pract ; 216(2): 152794, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31902551

RESUMO

OBJECTIVE: To evaluate the correlation between expression of p53, Livin, Excision repair cross-complementation group 1 (ERCC1), BRCA1 and Poly (ADP-ribose) polymerase 1 (PARP 1) in epithelial ovarian cancer (EOC) tissues with platinum-based chemotherapy and prognosis in patients who received either comprehensive surgical staging or cytoreductive surgery. METHODS: The protein expressions level of five potential regulators involved in chemo-resistance, including p53, Livin, ERCC1, BRCA1 and PARP1 in EOC tissues from 66 patients were evaluated using immunohistochemistry method. We also measured preoperative CA125 level measured by an electrochemiluminescence immunoassay (ECLIA) in all patients. Cox proportional hazard regression model was established to identify whether these proteins are associated with overall survival. RESULTS: Chemo-resistance and poor overall survival were shown to be significantly related with positive expressions of p53, Livin, ERCC1, BRCA1 and PARP1. The evaluation of risk factors on the chemo-resistance showed that ERCC1 and BRCA1 are strong risk factors (OR: 21.12 and 21.61, all P < 0.01), while the positive expression of ERCC1, BRCA1 and PARP1 was significantly highly associated with the overall survival (HR: 3.9, 3.7 and 2.6, all P < 0.05, respectively). CA125 levels were significantly higher in patients with positive expression of P53, BRCA1, ERCC1 or Livin compared with those with negative expression (471:146, 667:260, 494:261 and 4589:89 U/ml, respectively, all P < 0.05). CONCLUSIONS: The elevated expression levels of ERCC1 and BRCA1 were identified as significant risk factors for chemo-resistance in EOC. Reduced expression levels of ERCC1, BRCA1 and PARP1 were significantly associated with better overall survival. The CA125 levels were significantly higher in patients with EOC specimens that were positive of p53, BRCA1, ERCC1 and Livin.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína BRCA1/metabolismo , Carcinoma Epitelial do Ovário/metabolismo , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Ovarianas/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/tratamento farmacológico , Prognóstico
13.
RSC Adv ; 10(14): 8558-8567, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35497830

RESUMO

To improve the utilization of lignin, much effort has been devoted to lignin depolymerization with the aim to decrease waste and enhance profitability. Here, a dual property (acid and base) catalyst, namely S2O8 2--K2O/TiO2, was carefully researched. Upon loading S2O8 2- and K2O onto TiO2, acid and base sites emerged, and S2O8 2- and K2O mutually enhanced the acid and base strengths of the catalyst enormously; this indeed facilitated lignin depolymerization. Under appropriate conditions, the yields of liquid product, petroleum ether soluble (PE-soluble) product and total monomer products were 83.76%, 50.4% and 28.96%, respectively. The constituents of the PE-soluble fraction, which are mainly monomers and dimers, can be used as liquid fuels or additives. In addition, after the catalyst was modified by Ni, better results were obtained. Surprisingly, it was found that the Ni enhanced not only the hydrogenation capacity but also the acidity. The highest high heating value (HHV) of the liquid product (33.6 MJ kg-1) was obtained, and the yield of PE-soluble product increased from 50.4 to 56.4%. The product can be utilized as a fuel additive or be converted to bio-fuel. This catalysis system has significant potential in the conversion of lignin to bio-fuel.

14.
RSC Adv ; 10(71): 43599-43606, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-35519679

RESUMO

Efficient cleavage of aryl-ether linkages is a key strategy for generating aromatic chemicals and fuels from lignin. Currently, a popular method to depolymerize native/technical lignin employs a combination of Lewis acid and hydrogenation metal. However, a clear mechanistic understanding of the process is lacking. Thus, a more thorough understanding of the mechanism of lignin depolymerization in this system is essential. Herein, we propose a detailed mechanistic study conducted with lignin model compounds (LMC) via a synergistic Co-Zn/Off-Al H-beta catalyst that mirrors the hydrogenolysis process of lignin. The results suggest that the main reaction paths for the phenolic dimers exhibiting α-O-4 and ß-O-4 ether linkages are the cleavage of aryl-ether linkages. Particularly, the conversion was readily completed using a Co-Zn/Off-Al H-beta catalyst, but 40% of α-O-4 was converted and ß-O-4 did not react in the absence of a catalyst under the same conditions. In addition, it was found that the presence of hydroxyl groups on the side chain, commonly found in native lignin, greatly promotes the cleavage of aryl-ether linkages activated by Zn Lewis acid, which was attributed to the adsorption between Zn and the hydroxyl group. Followed by the cobalt catalyzed hydrogenation reaction, the phenolic dimers are degraded into monomers that maintain aromaticity.

15.
Org Lett ; 21(19): 7938-7942, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31553199

RESUMO

We have successfully developed a green and efficient multicomponent reaction protocol to synthesize S-aryl dithiocarbamates under visible light. Most appealingly, the reaction can proceed smoothly without adding any transition-metal catalysts, ligands, or photocatalysts while minimizing chemical wastes and metal residues in the end products. The advantages of this method meet the requirements of sustainable and green synthetic chemistry, and it provides a straightforward way to create valuable S-aryl dithiocarbamates.

16.
Bioresour Technol ; 284: 293-301, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30952057

RESUMO

A series of non-precious metal/metal oxide nickel-cobalt catalysts was prepared for a highly efficient depolymerization of Kraft lignin (KL) into liquid fuels using amorphous TiZr-oxide (Ti1-yZryO2) as a carrier. The effects of Ni-NiOx, Co-CoOx, NiCo-NiCoOx, NiCoOx and NiCo catalysts supported on amorphous TiZr-oxide carrier on KL depolymerization were investigated. It was found that the NiCo-NiCoOx/Ti1-yZryO2 catalyst is optimal for converting KL to petroleum ether (PE)-soluble product (mainly composed of monomers and dimers) in an 80.2% high yield at 320 °C for 24 h, with excellent reusability and a low formation of char. Under these conditions, the higher heating value (HHV) increased from 25.11 to 33.89 MJ/kg. A meticulous study on NiCo-NiCoOx/Ti1-yZryO2 catalysts revealed that the synergistic effect among Lewis acid sites, basic sites and metal active sites played an important role in obtaining high yields of monomers and low rates of char formation during lignin conversion.


Assuntos
Cobalto/química , Lignina/química , Níquel/química , Óxidos/química , Titânio/química , Zircônio/química , Catálise , Polimerização , Solventes/química
17.
Bioresour Technol ; 269: 346-354, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30195227

RESUMO

In this study, a novel modified nickel/H-beta (Ni/DeAl-beta) catalyst, which has active acidic sites and hydrogen binding sites, was prepared and used to produce liquefied fuel from lignin. The bifunctional Ni/DeAl-beta catalyst efficiently converted kraft lignin into liquefied fuel due to the synergistic effect of aluminum Lewis acid sites and nickel hydrogen binding sites. At a nickel content of 0.6 mmol/gzeolite, the Ni/DeAl-beta catalyst gave a high liquid product yield of 88.6% at 300 °C for 36 h. Most of the liquid product was dissolved in petroleum ether (73% of 88.6%), which was mainly composed of monomeric and dimeric degradation products. Under these conditions, the higher heating values (HHV) increased from 24.9 MJ/kg for kraft lignin to 32.0 MJ/kg for the liquid product. These results demonstrated the bifunctional Ni/DeAl-beta catalyst could be an efficient catalyst for lignin to liquefied fuel conversion.


Assuntos
Biocombustíveis , Lignina/química , Níquel , Catálise , Polimerização
18.
Biomed Pharmacother ; 79: 166-75, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27044825

RESUMO

OBJECTIVE: CD154 (CD40L) is a protein that is primarily expressed on activated T cells and is a member of the TNF superfamily of molecules. It binds to CD40 on antigen-presenting cells (APC), which leads to many effects depending on the target cell type. Being an activator of immune cells, CD40L has also been shown to directly induce apoptosis in tumor cells by multiple mechanisms. To understand the role of sCD40L in regulating the proliferation of epithelial ovarian cancer cells treated or untreated with cisplatin. METHODS: Epithelial ovarian cancer cells: SKOV3 and its cisplatin-resistant strain SKOV3/DDP cells were used to test the effect of sCD40L and cisplatin. The proliferation of SKOV3 and SKOV3/DDP cells were measured by MTT. Cell cycle was assessed by flow cytometry. The mRNA expressions of targeted genes were detected by qRT-PCR. The protein expressions were detected by Western blotting. RESULTS: sCD40L showed a significant dose-dependence inhibitory effect on the proliferation of ovarian cancer cell lines. sCD40L in combination with cisplatin could sensitized SKOV3/DDP cells to cisplatin treatment and reversed the drug resistance of SKOV3/DDP cells. The reversal ratios of 1 µg/ml sCD40L combined with cisplatin in SKOV3 and SKOV3/DDP cells were 2.11, 2.71, while the reversal ratios of 2 µg/ml sCD40L combined with cisplatin in SKOV3 and SKOV3/DDP cells were 3.78, 5.20, respectively. sCD40L or sCD40L combined cisplatin increased tumor cells in G0/G1 phase. sCD40L in combination with cisplatin decreased the expression levels of GST-π, LRP, Survivin, p53 and Bcl-2 in both epithelial ovarian cancer cell lines. The protein expression level of GST-π, LRP and P53 protein was also decreased upon sCD40L in combination with cisplatin although the expression level of Bcl-2 and survivin protein had no significant difference. CONCLUSION: sCD40L inhibits the proliferation of SKOV3 and SKOV3/DDP cells. The combined application of sCD40L and cisplatin can strength the inhibitory effect of cisplatin, and to a certain extent, reversing the resistance to cisplatin in SKOV3/DDP cells. sCD40L could lead a cell block in G0/G1 phase and make the cell growth restrained. sCD40L could induce SKOV3 and SKOV3/DDP cells apoptosis and reverse drug resistance through cutting GST-π mRNA, LRP mRNA, survivin mRNA, p53 mRNA and Bcl-2 mRNA and decreasing the expression of GST-π, LRP and P53 protein in SKOV3 and SKOV3/DDP cells, which provides in-vivo experiment basis to the application of sCD40L as a drug improving ovarian cancer cells sensitivity to cisplatin.


Assuntos
Ligante de CD40/farmacologia , Cisplatino/farmacologia , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Antígenos CD40/genética , Antígenos CD40/metabolismo , Carcinoma Epitelial do Ovário , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Neoplasias/metabolismo , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Solubilidade
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