Search

Electrochemical carbon dioxide reduction reaction using sustainable energy is a promising approach of synthesizing chemicals and fuels, yet is highly energy intensive. The oxygen evolution reaction is particularly problematic, which is kinetically sluggish and causes anodic carbon loss. In this context, we couple CO2 electrolysis with hydrogen oxidation reaction in a single electrochemical cell. A Ni(OH)2/NiOOH mediator is used to fully suppress the anodic carbon loss and hydrogen oxidation catalyst poisoning by migrated reaction products. This cell is highly flexible in producing either gaseous (CO) or soluble (formate) products with high selectivity (up to 95.3%) and stability (>100 h) at voltages below 0.9 V (50 mA cm−2). Importantly, thanks to the "transferred" oxygen evolution reaction to a water electrolyzer with thermodynamically and kinetically favored reaction conditions, the total polarization loss and energy consumption of our H2-integrated CO2 reduction reaction, including those for hydrogen generation, are reduced up to 22% and 42%, respectively. This work demonstrates the opportunity of combining CO2 electrolysis with the hydrogen economy, paving the way to the possible integration of various emerging energy conversion and storage approaches for improved energy/cost effectiveness. Electrochemical CO2 reduction is a promising method of producing sustainable chemicals and fuels, yet is highly energy intensive. Here, the authors couple CO2 electrolysis with hydrogen oxidation using a Ni(OH)2/NiOOH auxiliary electrode to enhance energy efficiency. [ABSTRACT FROM AUTHOR]

Simple Summary: Chemotherapy has been widely used in clinic to treat various types of tumors, although severe side effects have been the most critical limitation of this treatment modality. For a long time, it has been believed that toxicity derives from the apoptosis of normal cells induced by the use of chemotherapeutic drugs due to their off-target biodistribution. In 2017, a breakthrough finding by Shao Feng's group showed that the side effects were related to pyroptosis caused by chemotherapeutic-drug-induced GSDME activation, and, interestingly, pyroptosis shares the same upstream signaling molecule with apoptosis, i.e., the caspase-3 activation. From then on, great research attention has been paid to chemotherapy-induced pyroptosis. In reality, pyroptosis is a "double-edged sword", causing side effects in normal tissue, but also being able to promote antitumor effects, owing to its regulation of antitumor immunity. Therefore, rationally balancing the cell apoptosis and pyroptosis of caspase-3-activating chemotherapy is critically important for better antitumor therapy. This critical review aims to summarize recent progress in the field, focusing on how to balance cell apoptosis and pyroptosis for better tumor chemotherapy. Chemotherapy is a standard treatment modality in clinic that exerts an antitumor effect via the activation of the caspase-3 pathway, inducing cell death. While a number of chemotherapeutic drugs have been developed to combat various types of tumors, severe side effects have been their common limitation, due to the nonspecific drug biodistribution, bringing significant pain to cancer patients. Recently, scientists found that, besides apoptosis, chemotherapy could also cause cell pyroptosis, both of which have great influence on the therapeutic index. For example, cell apoptosis is, generally, regarded as the main mechanism of killing tumor cells, while cell pyroptosis in tumors promotes treatment efficacy, but in normal tissue results in toxicity. Therefore, significant research efforts have been paid to exploring the rational modulation mode of cell death induced by chemotherapy. This critical review aims to summarize recent progress in the field, focusing on how to balance cell apoptosis and pyroptosis for better tumor chemotherapy. We first reviewed the mechanisms of chemotherapy-induced cell apoptosis and pyroptosis, in which the activated caspase-3 is the key signaling molecule for regulating both types of cell deaths. Then, we systematically discussed the rationale and methods of switching apoptosis to pyroptosis for enhanced antitumor efficacy, as well as the blockage of pyroptosis to decrease side effects. To balance cell pyroptosis in tumor and normal tissues, the level of GSDME expression and tumor-targeting drug delivery are two important factors. Finally, we proposed potential future research directions, which may provide guidance for researchers in the field. [ABSTRACT FROM AUTHOR]

In the field of photocatalysis, building a heterojunction is an effective way to promote electron transfer and enhance the reducibility of electrons. Herein, the S‐scheme heterojunction photocatalyst (CoS2/Zn0.5Cd0.5S) of CoS2 nanospheres modified Zn0.5Cd0.5S solid solution was synthesized and studied. The H2 evolution rate of the composite catalyst reached 25.15 mmol g−1 h−1, which was 3.26 times that of single Zn0.5Cd0.5S, whereas pure CoS2 showed almost no hydrogen production activity. Moreover, CoS2/Zn0.5Cd0.5S had excellent stability and the hydrogen production rate after six cycles of experiments only dropped by 6.19 %. In addition, photoluminescence spectroscopy and photoelectrochemical experiments had effectively proved that the photogenerated carrier transfer rate of CoS2/Zn0.5Cd0.5S was better than CoS2 or Zn0.5Cd0.5S single catalyst. In this study, the synthesized CoS2 and Zn0.5Cd0.5S were both n‐type semiconductors. After close contact, they followed an S‐scheme heterojunction electron transfer mechanism, which not only promoted the separation of their respective holes and electrons, but also retained a stronger reduction potential, thus promoting the reduction of H+ protons in photocatalytic experiments. In short, this work provided a new basis for the construction of S‐scheme heterojunction in addition to being used for photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

Due to the poor photocatalytic hydrogen evolution ability of pure CdS, we need to develop a photocatalytic hydrogen evolution catalyst with high activity and no precious metal doping. Therefore, in this article, we used a simple hydrothermal synthesis of CdS nanoparticles, using water as a carrier, loading a small amount of amorphous CoS, by changing the loading ratio of amorphous CoS, synthesized TYPE–II type heterojunction composite catalyst CCS. The successful synthesis of the composite catalyst CCS was verified by XRD, SEM and other characterization methods. UV–vis, PL and other characterization showed that the supported amorphous CoS could significantly improve the photocatalytic activity of CdS, and the photochemical detection also showed that the performance of composite catalyst CCS was better than that of pure CdS. Using Na2S and Na2SO3 mixed solution as electron sacrificial agent, the hydrogen production performance of CCS composite catalyst was determined through hydrogen evolution experiment and cyclic stability experiment. It was found that the sacrificial agent had a great promotion effect on the hydrogen production performance of photocatalyst. It was found that the hydrogen production rate of the composite catalyst could reach 2.01 mmol·g−1·h−1, which was 6.3 times of the pure CdS. This study offers a novel approach for the design of amorphous–based nanostructures as efficient hydrogen evolution cocatalysts. First, CdS are excited by light, consuming S2− and SO32− ions in the sacrificial agent, generating a large number of electrons and holes. Due to the energy difference between the conducting band (CB) of CdS and amorphous CoS, the electrons are transferred from the surface of CdS to the conducting band (CB) of amorphous CoS, while the electrons obtained from water and H+ in the sacrificial agent are reduced to H2. The amorphous CoS is used as the transfer medium of electron acceptor, and the synergistic effect between heterojunctions is used to improve the charge separation efficiency and electron transfer rate. Therefore, the photocatalytic hydrogen production effect of the composite catalyst CCS–7 has been greatly improved. [ABSTRACT FROM AUTHOR]

One of the most effective methods to improve electron-transfer efficiency and photocatalytic reaction activity is to construct a photocatalyst with a heterojunction interface. Herein, a WO3/CoS2 n–n heterojunction composite catalyst was synthesized, and used in photocatalytic hydrogen evolution, and was optimized by adjusting the pH of the triethanolamine solution, the amount of Eosin Y added, and the content of WO3 in the composite catalyst. After 5 h of photocatalytic reaction, WO3/CoS2 (WCS-2) had a H2 production of 221.15 μmol, which was 80.41 times that of single WO3 and 2.17 times that of CoS2, and had good stability. XRD, SEM, TEM, and XPS characterization results indicated that WO3/CoS2 was successfully prepared. Fluorescence test and electrochemical test results showed that the WO3/CoS2 catalyst had a higher photoelectron transfer efficiency. Finally, it is pointed out that WO3/CoS2 enhanced the photocatalytic activity, which may be due to the electron migration of WO3 and CoS2 following the Z-scheme mechanism. This work presents a new idea for constructing n–n heterojunction to enhance the activity in photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

A novel composite perovskite LaNiO3 photocatalyst modified by MoS2 was synthesized by sol-high temperature calcination. When the molar ratio of La/Ni was 2:1, MoS2 accounts for 3% of the MoS2/LaNiO3 composite catalyst. The hydrogen production activity is up to 47.1 μmol h−1. In the visible range (≥ 420 nm), the hydrogen generation of the composite photocatalyst is increased more than three times that of pure LaNiO3. It is described that the hydrogen production capacity of catalytic materials formed by MoS2-modified LaNiO3 is significantly improved under visible light, the electron and hole pairs are effectively separated, the electron transfer rate is increased, and the recombination of electron and hole pairs is reduced. Furthermore, the experimental results were measured by energy spectrum (XPS), X-ray diffraction (XRD), photoluminescence spectroscopy (PL), scanning electron microscope (SEM), UV–Vis transmission electron microscopy (TEM), and electrochemical workstation. This is consistent with the hydrogen production capacity of the catalyst. [ABSTRACT FROM AUTHOR]

The diploid species G. herbaceum (A1) and G. raimondii (D5) are the progenitors of allotetraploid cotton, respectively. However, hybrids between G. herbaceum and G. raimondii haven’t been reported. In the present study, hybridization between G. herbaceum and G. raimondii was explored. Morphological, cytogenetic and molecular analyses were used to assess the hybridity. The interspecific hybrid plants were successfully obtained. Most of the morphological characteristics of the hybrids were intermediate between G. herbaceum and G. raimondii. However, the color of glands, anther cases, pollen and corolla, and the state of bracteoles in hybrids were associated with the G. herbaceum. The color of staminal columns and filaments in hybrids were associated with G. raimondii. Cytogenetic analysis confirmed abnormal meiotic behavior existed in hybrids. The hybrids couldn’t produce boll-set. Simple sequence repeat results found that besides the fragments inherited from the two parents, some novel bands were amplified in hybrids, indicating that potential mutations and chromosomal recombination occurred between parental genomes during hybridization. These results may provide some novel insights in speciation, genome interaction, and evolution of the tetraploid cotton species. [ABSTRACT FROM AUTHOR]

In the field of photocatalysis, building a heterojunction is an effective way to promote electron transfer and enhance the reducibility of electrons. Herein, the S-scheme heterojunction photocatalyst (CoS 2 /Zn 0.5 Cd 0.5 S) of CoS 2 nanospheres modified Zn 0.5 Cd 0.5 S solid solution was synthesized and studied. The H 2 evolution rate of the composite catalyst reached 25.15 mmol g -1  h -1 , which was 3.26 times that of single Zn 0.5 Cd 0.5 S, whereas pure CoS 2 showed almost no hydrogen production activity. Moreover, CoS 2 /Zn 0.5 Cd 0.5 S had excellent stability and the hydrogen production rate after six cycles of experiments only dropped by 6.19 %. In addition, photoluminescence spectroscopy and photoelectrochemical experiments had effectively proved that the photogenerated carrier transfer rate of CoS 2 /Zn 0.5 Cd 0.5 S was better than CoS 2 or Zn 0.5 Cd 0.5 S single catalyst. In this study, the synthesized CoS 2 and Zn 0.5 Cd 0.5 S were both n-type semiconductors. After close contact, they followed an S-scheme heterojunction electron transfer mechanism, which not only promoted the separation of their respective holes and electrons, but also retained a stronger reduction potential, thus promoting the reduction of H + protons in photocatalytic experiments. In short, this work provided a new basis for the construction of S-scheme heterojunction in addition to being used for photocatalytic hydrogen production., (© 2021 Wiley-VCH GmbH.)

Excessive oxidative stress is a major causative factor of endothelial dysfunction in hypertension. As an endogenous pro-oxidant, thioredoxin-interacting protein (TXNIP) contributes to oxidative damage in various tissues. The present study aimed to investigate the role of TXNIP in mediating endothelial dysfunction in hypertension. In vivo , an experimental model of acquired hypertension was established with two-kidney, one-clip (2K1C) surgery. The expression of TXNIP in the vascular endothelial cells of multiple vessels was significantly increased in hypertensive rats compared with sham-operated rats. Resveratrol, a TXNIP inhibitor, suppressed vascular oxidative damage and increased the expression and activity of eNOS in the aorta of hypertensive rats. Notably, impaired endothelium-dependent vasodilation was effectively improved by TXNIP inhibition in hypertensive rats. In vitro , we observed that Ang II increased the expression of TXNIP in primary human aortic endothelial cells (HAECs) and that TXNIP knockdown by RNA interference alleviated cellular oxidative stress damage and mitigated the impaired eNOS activation and intracellular nitric oxide (NO) production observed in Ang II-treated HAECs. However, inhibiting thioredoxin (TRX) with PX-12 completely blunted the protective effect of silencing TXNIP. In addition, TXNIP knockdown facilitated TRX expression and promoted TRX nuclear translocation to further activate AP1 and REF1. TRX overexpression exhibited favorable effects on eNOS/NO homeostasis in Ang II-treated HAECs. Thus, TXNIP contributes to oxidative stress and endothelial dysfunction in hypertension, and these effects are dependent on the antioxidant capacity of TRX, suggesting that targeting TXNIP may be a novel strategy for antihypertensive therapy., (© 2020 Chongqing Medical University. Production and hosting by Elsevier B.V.)