Boron Bifunctional Catalysts for Rapid Degradation of Persistent Organic Pollutants in a Metal-Free Electro-Fenton Process: O2 and H2O2 Activation Process.

Metals usually served as the active sites of the heterogeneous bifunctional electro-Fenton reaction, which faced the challenge of poor stability under acidic or even neutral conditions. Exploring a metal-free heterogeneous bifunctional electro-Fenton catalyst can effectively solve the above problems. In this work, a stable metal-free heterogeneous bifunctional boron-modified porous carbon catalyst (BTA-1000) was synthesized. For the BTA-1000 catalyst, the yield of H2O2 (294 mg/L) significantly increased. The degradation rate of phenol by BTA-1000 (0.242 min-1) increased by an order of magnitude, compared with the porous carbon catalyst (0.0105 min-1). The BTA catalyst could rapidly degrade industrial dye wastewater, and its specific energy consumption was 5.52 kW h kg-1 COD-1, lower than that in previous reports (6.38-7.4 kW h kg-1 COD-1). DFT and XPS revealed that C═O and -BC2O groups jointly promoted the generation of H2O2, and the -BCO2 group played dominant roles in the generation of •OH because the oxygen atom near the electron-giving groups (-BCO2 group) facilitated the formation of hydrogen bond and H2O2 adsorption. This work gained deep insights into the reaction mechanism of the boron-modified porous carbon catalyst, which helped to guide the development of metal-free heterogeneous bifunctional electro-Fenton catalysts.

Errate: Identification of NDRG Family Member 4 (NDRG4) and CDC28 Protein Kinase Regulatory Subunit 2 (CKS2) as Key Prognostic Genes in Adrenocortical Carcinoma by Transcriptomic Analysis.

The original published paper had the same image for Figure 5E and 5F. Figure 5 should have been as follows: Reference: Zhengqing Yang, Hui Cheng, Yazhou Zhang, Yan Zhou. Identification of NDRG Family Member 4 (NDRG4) and CDC28 Protein Kinase Regulatory Subunit 2 (CKS2) as Key Prognostic Genes in Adrenocortical Carcinoma by Transcriptomic Analysis. Med Sci Monit, 2021; 27:e928523. DOI: 10.12659/MSM.928523.

Identification of NDRG Family Member 4 (NDRG4) and CDC28 Protein Kinase Regulatory Subunit 2 (CKS2) as Key Prognostic Genes in Adrenocortical Carcinoma by Transcriptomic Analysis.

BACKGROUND Adrenocortical carcinoma (ACC) is an aggressive cancer with heterogeneous outcomes. In this study, we aimed to investigate genomic and prognostic features of ACC. MATERIAL AND METHODS Clinical, pathologic, and transcriptomic data from 2 independent datasets derived from ACC samples (TCGA-ACC dataset, GEO-GSE76021 dataset) were collected. Weighted gene co-expression network analysis (WGCNA) and survival analyses were performed to identify prognostic genes. Pathway analysis was performed for mechanistic analysis. xCell deconvolution was performed for tumor microenvironment analysis. RESULTS In the TCGA-ACC cohort, WGCNA identified a prognostic module of 5408 genes. Differential expression analysis identified 1969 genes that differed in expression level between long-term and short-term survivors. Univariate Cox regression model analysis identified 8393 genes with prognostic value. The intersection of these gene sets included 820 prognostic genes. Similar protocols were performed for the GSE76021 dataset, and 5 candidate genes were identified. Further intersection of these genes finally identified NDRG4 and CKS2 as key prognostic genes. Multivariate Cox regression model analysis validated the prognostic value of NDRG4 (HR=0.61, 95% CI 0.46-0.80) and CKS2 (HR=2.52, 95% CI 1.38-4.60). Moreover, NDRG4 and CKS2 expression predicted survival in patients treated with mitotane (P<0.001). Further mechanism exploration found an association between CKS2 and DNA mismatch repair pathways. Moreover, NDRG4 positively correlated with CD8⁺ T cell infiltration, while CKS2 negatively correlated with it. CONCLUSIONS We identified NDRG4 and CKS2 expression as key prognostic genes in ACC, which may help in risk stratification of ACC. Moreover, a close relationship was found between CKS2 and mismatch repair pathways. Moreover, immune cell infiltration differed according to NDRG4 and CKS2 expression.

An innovative compound bed of EDI device with enhancing ion-exchange resins regeneration efficiency.

Electrodeionization (EDI) technology is limited by low regeneration efficiency of ion exchange resins, requirements of high-quality influent water, fouling of the ion exchange membrane and electrode, etc. In this work, a novel bed type called a compound bed in which cation and anion exchange resins were near the cation and anion exchange membrane and placed in layers, was proposed to implement high-efficiency regeneration of ion exchange resins. The influence of different operating conditions on the regeneration efficiency of ion exchange resins was elucidated as well. The regeneration efficiency of ion exchange resins could reach 73.1%, when the device was operated for 5 h under current density of 9 mA/cm2, with a cation and anion exchange resins ratio of 2: 3, influent water conductivity of 1,360 µS/cm and hardness of 400 mg/L. Therefore, the proposed compound bed structure not only widened the inlet water conditions, but also achieved the high-efficiency regeneration of ion exchange resins and anti-fouling of membranes and electrodes.

[Correlation between Indian hedgehog and damage degree of knee osteoarthritis cartilage].

OBJECTIVE: To explore the correlation between the Indian hedgehog and severity of knee osteoarthritis cartilage damage. METHODS: A total of 215 patients with osteoarthritis [97 males and 118 females with an average age of 65.2 ± 7.8 (49-78) years and 34 healthy persons [28 males and 6 females with an average age of 58.4 ± 8.7 (45-62) years were selected randomly and their cartilages in knee joints collected. The damage degree of osteoarthritis was evaluated by revised Markin scale. The Ihh mRNA was assessed by real-time polymerase chain reaction (PCR) and the Ihh protein expression examined by Western blot. RESULTS: According to the revised Mankin scale, the osteoarthritis samples were divided into 3 stages of severe, moderate and mild. Comparing with normal control group, the Ihh mRNA and protein expressions increased obviously in cartilage. With worsening cartilage damage, Ihh mRNA and protein expression increased accordingly. Statistical differences existed among the groups (normal: 1.00 ± 0.01; mild: 1.37 ± 0.02; moderate: 1.90 ± 0.02; severe: 2.13 ± 0.03; P < 0.01). And the damage degree of osteoarthritis was determined by injury extent of soft tissue in knee joint (Mankin scale). And the damage degree of cartilage was positively correlated with Ihh expression (r = 0.581, P < 0.01). CONCLUSION: Ihh expression is correlated with the damage degree of knee joint osteoarthritis.

Degradation of emerging contaminants in synthetic hydrolyzed urine by UV/peracetic acid: Free radical chemistry, and toxicity analysis.

The ecological impact of emerging contaminants (ECs) in aquatic environments has raised concerns, particularly with regards to urine as a significant source of such contaminants in wastewater. The current investigation used the UV/Peracetic Acid (UV/PAA) processes, an innovative advanced oxidation technology, to effectively separate two emerging pollutants from urine at its source, namely, ciprofloxacin (CIP) and bisphenol A(BPA). The research findings demonstrate that the presence of the majority of characteristic ions has minimal impact on the degradation of ECs. However, in synthetic hydrolyzed urine, only NH4+ inhibits the degradation of two types of ECs, with a more pronounced effect observed on CIP degradation compared to BPA.The impact of halogen ions, specifically Cl- and I-, on the degradation of CIP in synthetic hydrolyzed urine was a complex phenomenon. When these two halogen ions are present individually, the generation of reactive halogen species (RHS) within the system enhances the degradation of CIP. However, when both types of ions coexist, the formation of diatomic radical species partially inhibits degradation. In terms of BPA degradation, while the production of reactive chlorine species (RCS) to some extent hinders the reaction rate, the generation of reactive iodine species (RIS) promotes the overall process. CIP undergoes fragmentation of the piperazine and quinoline rings, decarboxylation, defluorination reactions, as well as substitution reactions, leading to the formation of products with simplified structures. The degradation of BPA occurs gradually through hydroxyl and halogen substitution as well as isopropyl cleavage. The preliminary toxicity analysis confirmed that the presence of halogen ions in urine resulted in the formation of halogenated products in two types of ECs, albeit with an overall reduction in toxicity. The UV/PAA processes was considered to be an effective and relatively safe approach for the separation of ECs in urine.

Impact of uranium on antibiotic resistance in activated sludge.

The emergence of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) in the environment is well established as a human health crisis. The impact of radioactive heavy metals on ecosystems and ultimately on human health has become a global issue, especially for the regions suffering various nuclear activities or accidents. However, whether the radionuclides can affect the fate of antibiotic resistance in bacteria remains poorly understood. Here, the dynamics of ARB, three forms of ARGs-intracellular ARGs (iARGs), adsorbed extracellular ARGs (aeARGs), and free extracellular ARGs (feARGs)-and microbial communities were investigated following exposure to uranium (U), a representative radioactive heavy metal. The results showed that 90-d of U exposure at environmentally relevant concentrations of 0.05 mg/L or 5 mg/L significantly increased the ARB concentration in activated sludge (p < 0.05). Furthermore, 90-d of U exposure slightly elevated the absolute abundance of aeARGs (except tetO) and sulfonamide iARGs, but decreased tetracycline iARGs. Regarding feARGs, the abundance of tetC, tetO, and sul1 decreased after 90-d of U stress, whereas sul2 showed the opposite trend. Partial least-squares path model analysis revealed that the abundance of aeARGs and iARGs under U stress was predominantly driven by increased cell membrane permeability/intI1 abundance and cell membrane permeability/reactive oxygen species concentration, respectively. Conversely, the changes in feARGs abundance depended on the composition of the microbial community and the expression of efflux pumps. Our findings shed light on the variations of ARGs and ARB in activated sludge under U exposure, providing a more comprehensive understanding of antibiotic resistance risks aggravated by radioactive heavy metal-containing wastewater.

Metagenomic insights into the distribution, mobility, and hosts of extracellular antibiotic resistance genes in activated sludge under starvation stress.

Extracellular antibiotic resistance genes (eARGs) are important emerging environmental pollutants in wastewater treatment plants (WWTPs). Nutritional substrate deficiency (i.e., starvation) frequently occurs in WWTPs owing to annual maintenance, water quality fluctuation, and sludge storage; and it can greatly alter the antibiotic resistance and extracellular DNA content of bacteria. However, the fate and corresponding transmission risk of eARGs in activated sludge under starvation stress remain largely unknown. Herein, we used metagenomic sequencing to explore the effects of starvation scenarios (carbon, nitrogen, and/or phosphorus deficiency) and environmental conditions (alternating anaerobic-aerobic, anaerobic, anoxic, and aerobic) on the distribution, mobility, and hosts of eARGs in activated sludge. The results showed that 30 days of starvation reduced the absolute abundances of eARGs by 40.9%-88.2%, but high-risk dual and multidrug resistance genes persisted. Starvation, particularly the simultaneous lack of carbon, nitrogen, and phosphorus under aerobic conditions, effectively alleviated eARGs by reducing the abundance of extracellular mobile genetic elements (eMGEs). Starvation also altered the profile of bacterial hosts of eARGs and the bacterial community composition, the latter of which had an indirect positive effect on eARGs via changing eMGEs. Our findings shed light on the response patterns and mechanisms of eARGs in activated sludge under starvation conditions and highlight starvation as a potential strategy to mitigate the risk of previously neglected eARGs in WWTPs.

Insight into the impacts and mechanisms of ketone stress on the antibiotic resistance in Escherichia coli.

Accumulation of toxic organic has posed a substantial pressure on the proliferation of bacterial resistance. While aromatic organics have been demonstrated to enhance the antibiotic resistance in bacteria, no information is yet available on the effects of non-aromatic organics on the variations of bacterial resistance. Here, we investigated the effects of a typical ketone (i.e., methylisobutanone (MIBK)) on the variations of antibiotic resistance in Escherichia coli (E. coli). The results showed that the growth of resistant E. coli under environmental concentration of 50 µg/L MIBK was firstly inhibited as explained by the transient disruption in the cell membrane and then recovered possibly due to the reactive oxygen species. Exposure to 50 µg/L MIBK gradually raised the abundance of representative resistance gene (ampR) in E. coli. In contrast, the high concentration of 50 mg/L MIBK continuously inhibited the growth of resistant E. coli by disrupting cell membrane and notably promoted the proliferation of ampR through enhancing the horizontal transformation and up-regulating the expression of efflux pump gene. These findings provided the first evidence for the evolution of bacterial resistance in response to ketone organics.