Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 6 de 6
Filter
Add more filters










Database
Language
Publication year range
1.
J Hazard Mater ; 471: 134273, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38653137

ABSTRACT

This study employs five UV-AOPs (PMS, PDS, H2O2, NaClO and NaClO2) to produce radicals (•OH, SO4•-, ClO•, O2•- and 1O2) and further comparatively studies their activity sequence and activity difference cause in toluene degradation. The toluene mineralization efficiency as a descending order is 73 % (UV-PMS) > 71 % (UV-PDS) > 70 % (acidified-UV-NaClO) > 55 % (UV-H2O2) > 36 % (UV-NaClO) > 35 % (UV-NaClO2); that of conversion efficiency is 99 % (acidified-UV-NaClO) > 95 % (UV-PMS) > 90 % (UV-PDS) > 74 % (UV-H2O2) > 44 % (UV-NaClO) > 41 % (UV-NaClO2). Acidic pretreatment significantly boosts the reactivity of UV-NaClO. ESR combined with radical quenching tests reveals the radicals' generation and evolution, and their contribution rates to toluene conversion, i.e. ClO• > SO4•- > O2•- > 1O2 > â€¢OH. Theoretical calculations further unveil the ring-opening reaction routes and the nature of the activity difference of different radicals. The minimum energy required for ring-opening reaction is 116.77, 150.63, 168.29 and 191.92 kJ/mol with respect to ClO•, SO4•-, 1O2 and •OH, and finding that the ClO•-HO• pair is the best for toluene mineralization. The difficulty for eliminating typical VOCs by using UV-AOPs method is determined as toluene > chlorobenzene > benzene > ethyl acetate.

2.
BMC Chem ; 18(1): 72, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38609951

ABSTRACT

Toluene, a prominent member of volatile organic compounds (VOCs), exerts a substantial adverse influence on both human life and the environment. In the context of advanced oxidation processes, the ·OH radical emerges as a highly efficient oxidant, pivotal in the elimination of VOCs. This study employs computational quantum chemistry methods (G4MP2//B3LYP/6-311++G(d,p)) to systematically investigate the degradation of toluene by ·OH radicals in an implicit solvent model, and validates the rationale of choosing a single-reference method using T1 diagnostics. Our results suggest three possible reaction mechanisms for the oxidation of toluene by ·OH: firstly, the phenyl ring undergoes a hydrogen abstraction reaction followed by direct combination with ·OH to form cresol; secondly, ·OH directly adds to the phenyl ring, leading to ring opening; thirdly, oxidation of sidechain to benzoic acid followed by further addition and ring opening. The last two oxidation pathways involve the ring opening of toluene via the addition of ·OH, significantly facilitating the process. Therefore, both pathways are considered feasible for the degradation of toluene. Subsequently, the UV-H2O2 system was designed to induce the formation of ·OH for toluene degradation and to identify the optimal reaction conditions. It was demonstrated that ·OH and 1O2 are the primary active species for degrading toluene, with their contribution ranking as ·OH > 1O2. The intermediates in the mixture solution after reactions were characterized using GC-MS, demonstrating the validity of theoretical predictions. A comparative study of the toluene consumption rate revealed an experimental comprehensive activation energy of 10.33 kJ/mol, which is consistent with the preliminary activation energies obtained via theoretical analysis of these three mechanisms (0.56 kJ/mol to 13.66 kJ/mol), indicating that this theoretical method can provide a theoretical basis for experimental studies on the oxidation of toluene by ·OH.

3.
Biosci Trends ; 18(1): 42-48, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38325823

ABSTRACT

Therapies for patients with unresectable hepatocellular carcinoma (uHCC) are currently popular. Current first-line standard-of-care treatments for uHCC are systematic therapies. However, treatments that combine locoregional therapy with systemic therapy are widely accepted in China and have demonstrated high rates of tumor response and conversion to resection with manageable toxicity. A literature review was performed by searching published literature in PubMed and Web of Science up to December 2023 for relevant articles on the use of triple therapy (transarterial chemoembolization combined with lenvatinib and anti-PD-1 antibodies) in uHCC. This review concentrates on the efficacy and safety of triple therapy with Chinese characteristics in patients with uHCC and describes the outcome of conversion surgery, degree of pathological necrosis, and effect prediction. This article will contribute to a comprehensive understanding of the role of triple therapy with Chinese characteristics in patients with uHCC.


Subject(s)
Carcinoma, Hepatocellular , Chemoembolization, Therapeutic , Liver Neoplasms , Phenylurea Compounds , Quinolines , Humans , Carcinoma, Hepatocellular/therapy , Liver Neoplasms/therapy , China
4.
J Hepatocell Carcinoma ; 10: 1827-1837, 2023.
Article in English | MEDLINE | ID: mdl-37850079

ABSTRACT

Purpose: Few reliable biomarkers for predicting the efficacy of triple therapy (lenvatinib + immune checkpoint inhibitors + transarterial chemoembolization) exist for patients with unresectable hepatocellular carcinoma (uHCC). This study explored the prognostic role of alpha-fetoprotein (AFP) and des-gamma-carboxyprothrombin (DCP) levels in patients with uHCC receiving triple therapy. Patients and Methods: This retrospective study included 93 patients with uHCC who received triple therapy at Fujian Provincial Hospital between August 2020 and November 2022. Depending on the respective baseline levels, the patients were divided into high-AFP and high-DCP groups. An early response was defined as an AFP or DCP concentration >50% less than the baseline concentration after 6 weeks of triple therapy. The primary endpoint was the objective response rate (ORR). The secondary endpoints were progression-free survival (PFS) and overall survival (OS). Results: After 6 weeks of triple therapy, 75.3% (58/77) and 78.9% (60/76) of patients in the high-AFP and high-DCP groups achieved an objective response. Early AFP and DCP responses were positively associated with ORR (high-AFP group: odds ratio [OR]: 13.542; 95% confidence interval [CI]: 3.991-45.950, p<0.001; high-DCP group: OR: 17.853; 95% CI: 4.478-71.179, p<0.001). In the high-AFP group, the 6-month, 12-month, and 18-month PFS and OS rates were higher in the AFP responders than those in the non-responders (PFS: 66.4%, 59.6%, 48.2% vs 42.3%, 19.3%, 0%, p<0.001; OS: 94.5%, 90.4%, 77.3% vs 75.6%, 66.2%, 49.6%, p=0.006). In the high-DCP group, the 6-month, 12-month, and 18-month PFS and OS rates were higher in the DCP responders than those in the non-responders (PFS: 67.4%, 57.7%, 39.0% vs 38.9%, 8.1%, 0%, p<0.001; OS: 94.7%, 94.7%, 83.3% vs 77.0%, 53.9%, 36.0%, p<0.001). Conclusion: After 6 weeks of triple therapy, an AFP or DCP reduction of >50% predicts better treatment outcomes in uHCC patients.

5.
Environ Sci Technol ; 56(14): 10423-10432, 2022 07 19.
Article in English | MEDLINE | ID: mdl-35794709

ABSTRACT

A novel microwave (MW) catalytic oxidation denitrification method was developed, which can deeply oxidize NO into nitrate/nitrite with little NO2 yield. A molecular-sieve-supported oxygen-vacancy-enriched Fe2O3-MnO2 catalyst (Ov-Fe-Mn@MOS) was fabricated. Physicochemical properties of the catalyst were revealed by various characterization methods. MW irradiation was superior to the conventional heating method in NO oxidation (90.5 vs 70.6%), and MW empowered the catalyst with excellent low-temperature activity (100-200 °C) and good resistance to H2O and SO2. Ion chromatography analysis demonstrated that the amount of nitrate/nitrite accounted for over 90.0% of the N products, but the main product gradually varied from nitrate to nitrite as the reaction proceeded because of the switching of the main reaction path of NO removal. Mechanism analyses clarified that NO oxidation was a non-radical catalytic reaction: (i) the chemisorbed NO on ≡Mn(IV) reacted with O2* to produce nitrate and (ii) the excited NO* due to MW irradiation reacted with the active O* generated from Ov···O2 to form nitrite. Density functional theory calculations combined with electron paramagnetic resonance tests revealed the promotional effects of Fe2O3 in (i) boosting the Ov's quantity; (ii) facilitating O2 adsorption; (iii) increasing the nitrite formation; and (iv) alleviating the suppression of SO2.


Subject(s)
Microwaves , Oxides , Catalysis , Manganese Compounds , Nitrates , Nitrites , Nitrogen Oxides , Oxidation-Reduction , Oxygen/chemistry
6.
Gene ; 591(1): 236-244, 2016 Oct 10.
Article in English | MEDLINE | ID: mdl-27397650

ABSTRACT

Peptidylprolyl isomerase A (PPIA) is a peptidyl-prolyl cis-trans isomerase that is known to play a critical role in the development of many human cancers. However, the precise biological function of PPIA in hepatocellular carcinoma (HCC) remains largely unclear. In this study, lentiviral overexpression vectors and small interfering RNA knockdown methods were employed to investigate the biological effects of PPIA in HCC. PPIA levels in HCC tissues and peritumoral tissues were detected by real-time Polymerase Chain Reaction (RT-PCR), Western blotting, and immunohistochemistry. Our results indicate that PPIA levels were significantly higher in the HCC tissues compared to the matched peritumoral tissues. Moreover, PPIA expression was significantly associated with tumor size in these tissues. Interestingly, serum PPIA (sPPIA) levels were significantly higher in healthy controls compared to the HCC patients. Knockdown or overexpression of PPIA was shown to downregulate and upregulate cell growth, respectively. Moreover, PPIA siRNA knockdown appears to promote doxorubicin-induced apoptosis in HCC cells, altering the expression of downstream apoptotic factors. In summary, our results indicate that PPIA may play a pivotal role in HCC by regulating cell growth and could serve as a novel marker and therapeutic molecular target for HCC patients.


Subject(s)
Apoptosis/drug effects , Carcinoma, Hepatocellular/enzymology , Carcinoma, Hepatocellular/pathology , Down-Regulation/drug effects , Doxorubicin/pharmacology , Liver Neoplasms/pathology , Peptidylprolyl Isomerase/genetics , Carcinoma, Hepatocellular/genetics , Caspase 7/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Gene Expression Regulation, Neoplastic/drug effects , Gene Knockdown Techniques , Humans , Liver Neoplasms/enzymology , Liver Neoplasms/genetics , Male , Middle Aged , Peptidylprolyl Isomerase/blood , Peptidylprolyl Isomerase/metabolism , RNA, Small Interfering/metabolism , Transfection , bcl-X Protein/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL