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1.
Environ Sci Technol ; 57(47): 18473-18482, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36727553

RESUMEN

Permanganate (Mn(VII)) is extensively applied in water purification due to its stability and ease of handling, but it is a mild oxidant for trace organic contaminants (TrOCs). Hence, there is significant interest in strategies for enhancing reaction kinetics, especially in combination with efficient and economical carbocatalysts. This study compared the performance of four carbocatalysts (graphite, graphene oxide (GO), reduced-GO (rGO), and nitrogen-doped rGO (N-rGO)) in accelerating sulfisoxazole (SSX) oxidation by Mn(VII) and found that GO exhibited the greatest catalytic performance. Besides, the Mn(VII)/GO system shows desirable capacities to remove a broad spectrum of TrOCs. We proposed that the degradation of SSX in Mn(VII)-GO suspensions follows two routes: (i) direct oxidation of SSX by Mn species [both Mn(VII) and in situ formed MnO2(s)] and (ii) a carbocatalyst route, where GO acts as an electron mediator, accepting electrons from SSX and transferring them to Mn(VII). We developed a mathematical model to show the contribution of each parallel pathway and found one-electron transfer is primarily responsible for accelerating SSX removal in the Mn(VII)/GO system. Findings in this study showed that GO provides a simple and effective strategy for enhancing the reactivity of Mn(VII) and provided mechanistic insights into the GO-catalyzed redox reaction between SSX and Mn(VII).


Asunto(s)
Óxidos , Sulfisoxazol , Oxidación-Reducción , Compuestos de Manganeso
2.
Transl Oncol ; 28: 101617, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36610242

RESUMEN

Oxaliplatin is a commonly used platinum drug for colorectal cancer (CRC). However, the treatment of CRC by oxaliplatin usually fails because of drug resistance, which results in a huge challenge in the therapy of CRC. Elucidation of molecular mechanisms may help to overcome oxaliplatin resistance of CRC. In our study, we revealed that KIAA1199 can promote oxaliplatin resistance of CRC. Mechanistically, KIAA1199 prevents oxaliplatin mediated apoptosis via up-regulated PARP1 derived from reduced endoplasmic reticulum stress induced by protein O-GlcNAcylation. In the meantime, KIAA1199 can also trigger epithelial mesenchymal transition by stabilizing SNAI1 protein via O-GlcNAcylation. Therefore, KIAA1199 has great potential to be a novel biomarker, therapeutic target for oxaliplatin resistance and metastasis of CRC.

3.
J Hazard Mater ; 433: 128772, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35358813

RESUMEN

In this study, we found that the introduction of Cu(II) (several µM, close to the concentration level of some real water/wastewater) in ferrate (Fe(VI)) oxidation can remarkably accelerate the abatement of various organic pollutants under slightly alkaline conditions. The results show that 5 µM sulfamethoxazole (SMX) can be completely degraded by Fe(VI) (50 µM) in the presence of 20 µM Cu(II) within 10 min at pH 8.0, which was 1.65 times higher than that by Fe(VI) alone. High-valent iron intermediates (i.e. Fe(V), Fe(IV)) and Cu(III) were generated as reactive species in the Cu(II)/Fe(VI) system, all of which contributed to the enhanced oxidation of SMX. Common water components, except for HCO3- and humic acid, exhibited no influence on SMX removal. Additionally, the enhanced removal of SMX by Cu(II)/Fe(VI) was also observed in real water with the benefit of total removal of Cu(II) by the ferrate resultant particles. Due to the presence of highly reactive and selective oxidant, the Cu(II)/Fe(VI) system could react readily with organic pollutants containing electron-rich moieties, such as phenol, olefin or amino groups. This study provided a simple, selective, and practical strategy for the abatement of organic pollutants and a simultaneous removal of Cu(II).


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Purificación del Agua , Hierro , Oxidación-Reducción , Sulfametoxazol , Agua , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
4.
Front Oncol ; 11: 650919, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34150618

RESUMEN

Prostate cancer (PCa) is a common aggressive disease worldwide which usually progresses into incurable castration-resistant prostate cancer (CRPC) in most cases after 18-24 months treatment. Androgen receptor (AR) has been considered as a crucial factor involved in CRPC and the study of AR as a potential therapeutic target in CRPC may be helpful in disease control and life-cycle management. In this study, we identified a potent small molecule compound, HG122, that suppressed CRPC cells proliferation and metastasis, and inhibited tumor growth both in subcutaneous and orthotopic tumor model. In addition, HG122 reduced the mRNA expression of PSA and TMPRSS2 which are target genes of AR, resulting in cell growth inhibition and metastasis suppression of CRPC, without affecting the expression of AR mRNA level. Mechanically, HG122 promoted AR protein degradation through the proteasome pathway impairing the AR signaling pathway. In conclusion, HG122 overcomes enzalutamide (ENZ) resistance in CRPC both in vitro and in vivo, thus suggesting HG122 is a potential candidate for the clinical prevention and treatment of CRPC.

5.
Chemosphere ; 282: 131115, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34119724

RESUMEN

Pharmaceuticals may pose serious potential risks, such as biological responses and chronic health effects, due to their ubiquitous in natural aquatic water bodies. In this study, we proposed an effective, feasible, and low-cost strategy for the abatement of pharmaceuticals (i.e., phenylbutazone (PBZ) and sulfinpyrazone (SPZ)) via Co3O4 nanoparticles (NPs) as heterogeneous catalyst in permanganate (Mn(VII)) oxidation for the first time. The performance of the Co3O4 NPs in permanganate oxidation is highly dependent on pH and its dosage. Co3O4 NPs play as electron shuttles in the catalytic permanganate oxidation process involving one-electron transfer with the oxidation of ≡CoII to ≡CoIII by permanganate and the formation of colloidal manganese dioxide (MnO2), as well as the reduction of the newly formed ≡CoIII to ≡CoII by organics and the production of oxidized organic byproducts. The degradation pathways of PBZ and SPZ in catalytic permanganate oxidation were proposed based on the liquid chromatography-tandem mass spectrometry (LC-MS/MS) results and Gaussian calculation, and the toxicity decay of pharmaceuticals during oxidation was observed. Considering the stability, reusability, and cost, Co3O4 coupled with Mn(VII) is suitable for water pretreatment and is potentially feasible for industrial application, which is not only effective for decomposing PBZ and SPZ, but also for eliminating their toxicity.


Asunto(s)
Nanopartículas , Preparaciones Farmacéuticas , Cromatografía Liquida , Compuestos de Manganeso , Oxidación-Reducción , Óxidos , Espectrometría de Masas en Tándem
6.
Environ Sci Technol ; 55(11): 7681-7689, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34009966

RESUMEN

Permanganate (Mn(VII)) has been widely applied as an oxidant in water treatment plants. However, compared with ozone, Fenton, and other advanced oxidation processes, the reaction rates of some trace organic contaminants (TrOCs) with Mn(VII) are relatively low. Therefore, further studies on the strategies for enhancing the oxidation of organic contaminants by Mn(VII) are valuable. In this work, 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO), as an electron shuttle, enhanced Mn(VII) oxidation toward various TrOCs (i.e., bisphenol A (BPA), phenol, estrone, sulfisoxazole, etc.). TEMPO sped up the oxidative kinetics of BPA by Mn(VII) greatly, and this enhancement was observed at a wide pH range of 4.0-11.0. The exact mechanism of TEMPO in Mn(VII) oxidation was described briefly as follows: (i) TEMPO was oxidized by Mn(VII) to its oxoammonium cation (TEMPO+) by electron transfer, which was the reactive species responsible for the accelerated degradation of TrOCs and (ii) TEMPO+ could decompose TrOCs rapidly with itself back to TEMPO or TEMPOH (TEMPO hydroxylamine). To further illustrate the interaction between TEMPO and target TrOCs, we explored the transformation pathways of BPA in Mn(VII)/TEMPO oxidation. Compared to Mn(VII) alone, adding TEMPO into the Mn(VII) solution significantly suppressed BPA's self-coupling and promoted hydroxylation, ring-opening, and decarboxylation. Moreover, the Mn(VII)/TEMPO system was promising for the abatement of TrOCs in real waters for humic acid, and ubiquitous cations/anions had no adverse or even beneficial impact on the Mn(VII)/TEMPO system.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Compuestos de Manganeso , Oxidación-Reducción , Óxidos
7.
ISA Trans ; 106: 271-282, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32674852

RESUMEN

Accurate sintering condition recognition (SCR) is an important precondition for optimal control of rotary kilns. However, the occurrence probability of abnormal conditions in the industrial field is much lower than normal, resulting in imbalanced class sintering samples in general. This significantly deteriorates the effectiveness of existing recognition models in abnormal condition detection. In this paper, an integrated framework considering class imbalance is proposed for sintering condition recognition. In the proposed framework, after analysing the characteristics of thermal signals by the Lipschitz method, four discriminant features are extracted to comprehensively describe different sintering conditions. In addition, focusing on the class imbalance of sintering samples, the kernel modification method is introduced to enhance the optimal marginal distribution machine (ODM), and a novel recognition model kernel modified the ODM (KMODM) is proposed for SCR. By constructing a new conformal transformation function to modify the ODM kernel function, KMODM optimizes the spatial distribution of training samples in the kernel space, thereby alleviating the detection accuracy deterioration of the minority class. The experimental results on real thermal signals and standard datasets show that the KMODM model can effectively handle imbalanced data. Based on this, the proposed SCR framework can reduce the misjudgement of abnormal conditions and balance the recognition accuracy of each condition.

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