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1.
Environ Res ; 237(Pt 1): 116962, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37619634

RESUMO

It is of great significance to develop the effective technique to treat phenol-containing wastewater. Herein, Fe-based prussian blue analogues-derived zero valent iron (ZVI) was successfully synthesized by one-step calcination method. Owing to high specific surface area and rich active sites, ZVI-2 possessed excellent performance in charge transfer. Notably, in comparison with conventional ZVI and Fe2+, ZVI-2 can effectively activate peroxymonosulfate (PMS) for achieving rapid degradation of phenol, and the highest removal efficiency of phenol reached 94.9% within 24 min. More importantly, developed ZVI-2/PMS oxidation system with good stability displayed strong anti-interference capability. Interestingly, Fe0 loaded on the surface of ZVI-2 can efficiently break the O-O bond of PMS to generate reactive oxygen species (i.e., SO4•-, OH•, O2•- and 1O2). As main adsorption sites of PMS, the existence of oxygen vacancy promote the formation of high-valent transition metal complexes (namely ZVI-2≡Fe4+=O). Under the combined action of reactive oxygen species and ZVI-2≡Fe4+=O, phenol can be eventually degraded into CO2 and H2O. The possible degradation pathways of phenol were also investigated. Furthermore, proposed ZVI-2/PMS oxidation system displayed great potential for application in the field of wastewater treatment. All in all, current work provided a valuable reference for design and application of Fe-based catalysts in PS-AOPs.

2.
Huan Jing Ke Xue ; 41(9): 3899-3907, 2020 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124268

RESUMO

To study the seasonal pollution characteristics and sources of water-soluble inorganic ions in atmospheric PM2.5 in Suqian City, 171 samples were collected at three monitoring points, which were in the water vapor channel, from May 2017 to January 2018. The mass concentrations of PM2.5 and nine water-soluble inorganic ions were analyzed. The results showed that the annual average concentration of water-soluble inorganic ions in PM2.5 in Suqian City was (44.08±34.61) µg ·m-3, accounting for 41.8% of PM2.5. The concentrations of these species were in the order of ρ(NO3-) > ρ(SO42-) > ρ(NH4+) > ρ(ρl-) > ρ(Na+) > ρ(Ca2+) > ρ(K+) > ρ(F-) > ρ(Mg2+); NO3-, SO42-, and NH4+ accounted for 75.6% of the total water-soluble ions. The annual average ratio of ρ(NO3-) to ρ(SO42-) was 1.53±0.88, indicating that mobile sources contributed more to PM2.5 pollution. Based on the correlation analysis of NH4+ and SO42-, NO3- may exist in the form of (NH4)2 SO4, NH4HSO4, or NH4NO3. According to the principal component analysis, secondary transformation, industrial pollution, biomass burning, and dust were the major sources of water-soluble inorganic ions. PM2.5concentrations were positively related to relative humidity in winter. Water vapor transmission is more likely to promote PM2.5 accumulation in winter.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Cidades , Monitoramento Ambiental , Íons/análise , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , Água
3.
J Thorac Dis ; 10(12): 6838-6845, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30746229

RESUMO

BACKGROUND: It remains controversial that whether transcervical resection (TC) was associated with better outcomes than video-assisted thoracoscopic surgery (VATS) in the treatment of antero-superior mediastinal tumors. We aimed to compare the safety and reliability between TC and VATS. METHODS: Between 2010 and 2012, 80 consecutive patients underwent antero-superior mediastinal tumor resection via TC (n=31) or VATS (n=49). Perioperative outcomes were compared. A propensity score-matched analysis was performed to control the potential confounders. RESULTS: A total of 41 men and 39 women with median age of 52.5 years were enrolled. No patient died during the perioperative course. After propensity matching, TC group was associated with less intraoperative blood loss (35.1±18.7 vs. 93.7±136.1 mL, P=0.034), less postoperative drainage (65.6±76.8 vs. 335.0±154.9 mL, P<0.001), shorter length of postoperative hospital stay (3.2±1.2 vs. 4.1±1.3 days, P=0.003) and less hospitalization expense (22,252.3±4,761.7 vs. 26,514.2±4,052.8 CNY, P=0.002) compared to VATS group. One patient with VATS was converted to open surgery due to intraoperative vessels damage. The postoperative complication was null in TC group while it was 6.1% (n=3) in VATS group (P=0.279), including 1 case of prolonged chest tube drainage and 2 cases of recurrent laryngeal nerve injury. CONCLUSIONS: TC for antero-superior mediastinal tumors is a safe procedure with better perioperative outcomes compared to VATS.

4.
Hepatobiliary Pancreat Dis Int ; 2(1): 73-6, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14607651

RESUMO

OBJECTIVES: To analyze the characteristics of early hepatocellular carcinoma by using multi-phase helical CT and assess the value of this method. METHODS: Multi-phase helical CT findings were reviewed double-blindly by radiologists. RESULTS: Altogether 24 lesions were found in 21 patients. In plain CT, the lesions were seen as hypodense or isodense areas. After contrast enhancement, 87.5% of the lesions showed regular or irregular hyperdense enhancement, whereas 12.5% demonstrated tumor vessels in arterial phase, which became hypodensed or isodensed nodules in portal phase or the hypodensed in delayed phase. The prevalence of density changes showed a hypo-hyper-hypo and hypo-hypo pattern. CONCLUSIONS: Multi-phase helical CT could reflect the blood supply of early hepatocelluar carcinoma, and is also convenient for the differential diagnosis of hepatic cavernous angioma, metastatic tumor, hepatic nodulous hyperplasia, and hepatic inflammatory granuloma.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Nat Immunol ; 4(11): 1074-82, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14528304

RESUMO

Although increasing evidence indicates that there is a direct link between ubiquitination and mono-ubiquitination and transcription in yeast, this link has not been demonstrated in higher eukaryotes. Here we show that the major histocompatibility complex (MHC) class II transactivator (CIITA), which is required for expression of genes encoding MHC class II molecules, is ubiquitinated. This ubiquitination enhanced the association of CIITA with both MHC class II transcription factors and the MHC class II promoter, resulting in an increase in transactivation function and in the expression of MHC class II mRNA. The degree of CIITA ubiquitination was controlled by histone acetylases (HATs) and deacetylases (HDACs), indicating that the crucial cellular processes mediated by these enzymes are linked to regulate transcription. Thus, ubiquitin positively regulates a mammalian coactivator by enhancing its assembly at the promoter.


Assuntos
Proteínas Nucleares , Transativadores/metabolismo , Ativação Transcricional , Ubiquitina/metabolismo , Animais , Cromatina/metabolismo , Antígenos de Histocompatibilidade Classe II/biossíntese , Antígenos de Histocompatibilidade Classe II/genética , Histona Desacetilases/metabolismo , Humanos , Regiões Promotoras Genéticas
6.
Mol Cell Biol ; 23(9): 3091-102, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12697811

RESUMO

The class II transactivator (CIITA) is a master transcriptional regulator of major histocompatibility complex class II (MHC-II) promoters. CIITA does not bind DNA, but it interacts with the transcription factors RFX5, NF-Y, and CREB and associated chromatin-modifying enzymes to form an enhanceosome. This report examines the effects of histone deacetylases 1 and 2 (HDAC1/HDAC2) on MHC-II gene induction by gamma interferon (IFN-gamma) and CIITA. The results show that an inhibitor of HDACs, trichostatin A, enhances IFN-gamma-induced MHC-II expression, while HDAC1/HDAC2 inhibits IFN-gamma- and CIITA-induced MHC-II gene expression. mSin3A, a corepressor of HDAC1/HDAC2, is important for this inhibition, while NcoR, a corepressor of HDAC3, is not. The effect of this inhibition is directed at CIITA, since HDAC1/HDAC2 reduces transactivation by a GAL4-CIITA fusion protein. CIITA binds to overexpressed and endogenous HDAC1, suggesting that HDAC and CIITA may affect each other by direct or indirect association. Inhibition of HDAC activity dramatically increases the association of NF-YB and RFX5 with CIITA, the assembly of CIITA, NF-YB, and RFX5 enhanceosome, and the extent of H3 acetylation at the MHC-II promoter. These results suggest a model where HDAC1/HDAC2 affect the function of CIITA through a disruption of MHC-II enhanceosome and relevant coactivator-transcription factor association and provide evidence that CIITA may act as a molecular switch to modulate MHC-II transcription by coordinating the functions of both histone acetylases and HDACs.


Assuntos
Antígenos de Histocompatibilidade Classe II/metabolismo , Histona Desacetilases/metabolismo , Interferon gama/farmacologia , Proteínas Repressoras/metabolismo , Transativadores/metabolismo , Acetilação , Animais , Fator de Ligação a CCAAT/genética , Fator de Ligação a CCAAT/metabolismo , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Genes MHC da Classe II/fisiologia , Antígenos de Histocompatibilidade Classe II/genética , Histona Desacetilase 1 , Histona Desacetilase 2 , Inibidores de Histona Desacetilases , Histona Desacetilases/genética , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Substâncias Macromoleculares , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Correpressor 1 de Receptor Nuclear , Regiões Promotoras Genéticas/fisiologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Transcrição de Fator Regulador X , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Complexo Correpressor Histona Desacetilase e Sin3 , Transativadores/efeitos dos fármacos , Transativadores/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional
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