Ag3PO4-anchored La2Ti2O7 nanorod as a Z-Scheme heterostructure composite with boosted photogenerated carrier separation and enhanced photocatalytic performance under natural sunlight.

Developing wide spectra-responsive photocatalysts has attracted considerable attention in the photocatalytic technology to achieve excellent catalytic activity. Ag3PO4, with strong response to light spectra shorter than 530 nm, shows extremely outstanding photocatalytic oxidation ability. Unfortunately, the photocorrosion of Ag3PO4 is still the biggest obstacle to its application. Herein, the La2Ti2O7 nanorod was used to anchor Ag3PO4 nanoparticles in this study, and a novel Z-Scheme La2Ti2O7/Ag3PO4 heterostructure composite was constructed. Remarkably, the composite showed strong responsive to most of the spectra in natural sunlight. The Ag0 formed in-situ acted as the recombination center of photogenerated carriers, which promoted their efficient separation and contributed to the improved photocatalytic performance of the heterostructure. When the mass ratio of Ag3PO4 in the La2Ti2O7/Ag3PO4 catalyst was 50%, the degradation rate constant of Rhodamine B (RhB), methyl orange (MO), chloroquine phosphate (CQ), tetracycline (TC), and phenol under natural sunlight irradiation were 0.5923, 0.4463, 0.1399, 0.0493, and 0.0096 min-1, respectively. Furthermore, the photocorrosion of the composite was greatly inhibited, 76.49% of CQ and 83.96% of RhB were still degraded after four cycles. Besides, the holes and O2•- played a significant role in RhB degradation, and it included multiple mechanisms of deethylation, deamination, decarboxylation, and cleavage of ring-structures. Moreover, the treated solution can also show safety to the water receiving environment. Overall, the synthesized Z-Scheme La2Ti2O7/Ag3PO4 composite exhibited immense potential for removing various organic pollutants through photocatalytic technology under natural sunlight irradiation.

AKG induces cell apoptosis by inducing reactive oxygen species-mediated endoplasmic reticulum stress and by suppressing PI3K/AKT/mTOR-mediated autophagy in renal cell carcinoma.

BACKGROUND: Alpha-ketoglutarate (AKG) or 2-oxoglutarate is a key substance in the tricarboxylic acid cycle (TCA) and has been known to play an important role in cancerogenesis and tumor progression. Renal cell carcinoma (RCC) is the most common type of kidney cancer, and it has a high mortality rate. Autophagy is a phenomenon of self-digestion, and its significance in tumor genesis and progression remains debatable. However, the mechanisms underlying how AKG regulates autophagy in RCC remain unknown. Thus, the purpose of this study was to assess the therapeutic efficacy of AKG and its molecular mechanisms. METHODS: RCC cell lines 786O and ACHN were treated with varying doses of AKG for 24 h. CCK-8, Transwell, and scratch wound healing assays were utilized to evaluate the role of AKG in RCC cells. Autophagy protein and PI3K/AKT/mTOR pathway protein levels were analyzed by Western blot. RESULTS: AKG inhibited the proliferation of RCC cells 786O and ACHN in a dose-dependent manner according to the CCK-8 assay. In addition, flow cytometry and Western blot analysis revealed that AKG dose-dependently triggered apoptosis and autophagy in RCC cells. By promoting cell apoptosis and autophagy, AKG dramatically suppressed tumor growth. Mechanistically, AKG induces autophagy by promoting ROS generation and inhibiting the PI3K/AKT/mTOR pathway. CONCLUSIONS: The anti-tumor effect of AKG promotes autophagy in renal cancer cells via mediating ROS-PI3K/Akt/mTOR, and may be used as a potential anticancer drug for kidney cancer.

Pyrocatechol Alleviates Cisplatin-Induced Acute Kidney Injury by Inhibiting ROS Production.

As one of the most common cancer chemotherapy drugs, cisplatin is widely used in cancer management. However, cisplatin-induced nephrotoxicity occurs in patients who receive this drug. This study is aimed at developing therapeutic agents that effectively alleviate the nephrotoxic effects during cisplatin treatment. We identified a compound named pyrocatechol (PCL) from a natural product library that significantly alleviated cisplatin-induced cytotoxicity in vitro. Pyrocatechol treatment substantially ameliorated cisplatin (20 mg · kg-1) treatment-induced neuropathological indexes, including inflammatory cell infiltration and apoptosis, in vivo. Mechanistically, pyrocatechol significantly prevented oxidative stress-induced apoptosis by activating glutathione peroxidase 4 (GPX4) to reduce reactive oxygen species (ROS) accumulation in cisplatin-treated cells. In addition, pyrocatechol significantly inhibited ROS-induced JNK/P38 activation. Thus, we found that pyrocatechol prevents ROS-mediated JNK/P38 MAPK activation, apoptosis, and cytotoxicity through GPX4. Our study demonstrated that pyrocatechol is a novel therapeutic agent against cisplatin-induced kidney injury.

Biomass ash pyrolyzed from municipal sludge and its adsorption performance toward tetracycline: effect of pyrolysis temperature and KOH activation.

Large amount of municipal sludge is difficult to handle; its resource utilization is an effective measure. In this study, the municipal sludge from sewage treatment plant was pyrolyzed without gas protection at different temperatures and potassium hydroxide (KOH) concentrations for activation. The pyrolysis products, named biomass ash, with higher surface area and enriched pore structures could be obtained at the pyrolysis temperature of 773 K. Moreover, the KOH activation for raw municipal sludge could further increase the surface area of the pyrolysis biomass ash. The maximum specific surface area was 44.71 m2/g, which was obtained under 2 mol/L KOH activation before pyrolysis at 773 K. And in this situation, the obtained pyrolysis biomass ash as adsorbent showed the maximum adsorption capacity of 50.75 mg/g toward tetracycline (TC). Moreover, the TC adsorption onto pyrolysis biomass ash obtained under various conditions followed the pseudo-second-order kinetic model. Adsorption thermodynamics analysis suggested the TC adsorption onto the pyrolysis biomass ash with no pre-activation was mainly due to the multi-molecule heterogeneous adsorption, while the TC adsorption onto pyrolysis biomass ash pretreated through the activation of KOH followed the monomer adsorption mechanism. This different adsorption mechanism was largely related to the pore structure, polarity, and aromaticity of the adsorbent.

Downregulation of Circular RNA circPSD3 Promotes Metastasis by Modulating FBXW7 Expression in Clear Cell Renal Cell Carcinoma.

Circular RNAs (circRNAs), a novel class of noncoding RNAs, have been shown to play critical regulatory roles in clear cell renal cell carcinoma (ccRCC). Metastasis is the main contributor to the poor prognosis of patients with ccRCC. However, the role of circRNAs in ccRCC metastasis has not been fully elucidated. In this study, microarray and RNA-seq analyses revealed that circPSD3 (hsa_circ_0002111) was dramatically downregulated in ccRCC tissues compared to adjacent nontumor tissues. A qRT-PCR analysis performed on our ccRCC cohorts confirmed the downregulation of circPSD3 in ccRCC tissues and further suggested that a low level of circPSD3 expression was associated with tumor metastasis in patients with ccRCC. Based on the results of functional studies, circPSD3 significantly inhibited cell migration, invasion, and the epithelial-mesenchymal transition (EMT) in vitro and blocked pulmonary metastasis in vivo. Mechanistically, circPSD3 functioned as a competing endogenous RNA for microRNA 25-3p (miR-25-3p) to regulate F-box and WD repeat domain-containing 7 (FBXW7) expression. Further verification indicated that circPSD3 overexpression restrained an EMT-like phenotype in cells, while miR-25-3p partially rescued these effects. In summary, circPSD3 inhibits tumor metastasis by repressing the miR-25-3p/FBXW7-EMT axis and might be developed as a potential diagnostic and therapeutic target for ccRCC.

Ag3PO4-based photocatalysts and their application in organic-polluted wastewater treatment.

Semiconductor photocatalysis technology has shown great potential in the field of organic pollutant removal, as it can use clean and pollution-free solar energy as driving force. The discovery of silver phosphate (Ag3PO4) is a major breakthrough in the field of visible light responsive semiconductor photocatalysis due to its robust capacity to absorb visible light < 520 nm. Furthermore, the holes produced in Ag3PO4 under light excitation possess a strong oxidation ability. However, the strong oxidation activity of Ag3PO4 is only achieved in the presence of electron sacrifice agents. Otherwise, photocorrosion would greatly reduce the reuse efficiency of Ag3PO4. This review thus focuses on the structural characteristics and preparation methods of Ag3PO4. Particularly, the recent advances in noble metal deposition, ion doping, and semiconductor coupling, as well as methods of magnetic composite modification for the improvement of catalytic activity and recycling efficiency of Ag3PO4-based catalysts, were also discussed, and all of these measures could enhance the catalytic performance of Ag3PO4 toward organic pollutants degradation. Additionally, some potential modification methods for Ag3PO4 were also proposed. This review thus provides insights into the advantages and disadvantages of the application of Ag3PO4 in the field of photocatalysis, clarifies the photocorrosion essence of Ag3PO4, and reveals the means to improve photocatalytic activity and stability of Ag3PO4. Furthermore, it provides a theoretical and methodological basis for studying Ag3PO4-based photocatalyst and also compiles valuable information regarding the photocatalytic treatment of organic polluted wastewater.

Novel visible-light-driven SrCoO3/Ag3PO4 heterojunction with enhanced photocatalytic performance for tetracycline degradation.

The semiconductor photocatalytic technology has been considerably studied due to its excellent catalytic performance in water pollution control. Herein, in this study, novel SrCoO3/Ag3PO4 composite materials with different SrCoO3 content were synthesized via a simple hydrothermal synthesis method. The characteristics of the as-prepared samples were detected through SEM/HRTEM, XRD, UV-vis DRS, PL, ESR, FT-IR, and XPS techniques, and then, the photocatalytic performance of SrCoO3/Ag3PO4 toward the degradation of tetracycline was investigated. When the mass ratio of SrCoO3 and Ag3PO4 in the composite was 1:1.5, the degradation rate constant of tetracycline in SrCoO3/Ag3PO4 (1:1.5) system is 0.0102 min-1, which is 1.7 times that of the Ag3PO4, and 3.78 times that of the SrCoO3. In addition, reactive species were also analyzed through the free radical trapping experiment and DMPO spin-trapping ESR spectra analysis, showing that OH•, h+, and O2•-participated in the catalytic degradation process of tetracycline to varying degrees. Finally, the photocatalytic mechanism of SrCoO3/Ag3PO4 was also proposed.

Metallothermic Reduction of Silica Nanoparticles to Porous Silicon for Drug Delivery Using New and Existing Reductants.

In this study, the influence of metals (Mg, Al, and Ca) and reaction conditions (time, temperature, and metal grain size) on the metallothermic reduction of Stöber silica nanoparticles (NPs) to form porous Si has been explored. Mg metal was found to be an effective reducing agent even at temperatures below its melting point; however, it also induced a high degree of structural damage and morphology change. Al was effective in reducing silica NPs only at its melting point or above, but the resulting particles retained a higher degree of structural morphology as compared to those reduced using Mg. Ca was found to be ineffective in reducing silica. A new reductant, a mixture of 70 % Mg and 30 % Al, was found to induce the least amount of morphology change, and the reactions proceeded at a temperature (450 °C) lower than those required with Mg or Al individually. Furthermore, porous Si NPs obtained using Mg, Al, and the mixture of 70 % Mg and 30 % Al as reductants have been investigated as carriers for ibuprofen loading and release. Porous Si obtained from reductions with Mg and the Mg/Al mixture showed higher drug loading and a sustained drug release profile, whereas porous Si obtained from Al reduction had lower loading and showed a conventional release profile over 24 h.