Assessment of Immune Status in Patients with Mismatch Repair Deficiency Endometrial Cancer.

Objective: This study introduced a novel subtype classification method for endometrial cancer (EC) with mismatch repair deficiency (MMRd) by employing immune status and prognosis as the foundational criteria. The goal was to enhance treatment guidance through precise subtype delineation. Methods: Study Cohort: This study encompassed a cohort of 119 patients diagnosed with MMRd-EC between 2015 and 2022. Analyses using t-tests and Mann-Whitney U-tests were performed to assess prognostic markers and peripheral blood immune cell profiles in patients with MutS deficiency (MutS-d) versus those with MutL deficiency (MutL-d). Logistic regression analysis was used to identify independent risk factors. Bioinformatics Analysis: An online database was used to assess the prognostic implications, immune cell infiltration, and immune checkpoint involvement associated with the deficiency of MutS versus MutL in EC. Results: Patients with MutL-d exhibited heightened risk factors, including elevated cancer grade and increased myometrial invasion, leading to poorer prognosis and shorter overall survival and progression-free survival. Regarding systemic immune status, patients with MutL-d demonstrated decreased peripheral blood lymphocyte percentage, lymphocyte count, and CD8+ T cell percentage. For local immunity, the infiltration of natural killer cells, CD8+ T cells, and cytotoxic T lymphocytes in the tumor tissue was reduced in patients with MutL-d. Additionally, patients with MutL-d exhibited lower expression of immune checkpoint markers. The composition of immune subtypes and survival outcomes also indicate that patients with MutL-d have a poorer immune status and prognosis than the patients with MutS-d. Conclusion: Patients with MMRd-EC can be subclassified according to MutS or MutL deficiency. Patients with MutS-d exhibited better immune status, prognosis, and immunotherapy benefits than those with MutL-d. These results can help guide patients to a more precise treatment.

ZnIn2S4 Heterojunctions Constructed with In-MOF Precursor for Photocatalytic Hydrogen Evolution without Cocatalysts.

Znln2S4 has great prospects for photocatalytic water splitting to hydrogen by visible light. Herein, a novel Znln2S4-In-MOF (ZnInMS4) photocatalyst is elaborately synthesized by in situ method with In-MOF as the template and In3+ as the source. ZnInMS4 overcomes the fast interface charge recombination and a sluggish charge lifetime via the formed heterojunctions. Photoelectrochemical measurements reveal that the charge-transfer kinetics is enhanced since In-MOF is introduced to act as a reliable charge-transport channel. ZnInMS4 exhibits outstanding cocatalyst-free H2 evolution rate of 70 µmol h-1 under irradiation (λ > 420 nm), which is 3.2-fold higher than that of Znln2S4. In addition, the ZnInMS4 photocatalyst shows good stability in the 16 h continuous reaction. This work illustrates the feasibility of the MOF precursor instead of inorganic salts to directly synthesize photocatalysts with high performance.

Consumption of a Taiwanese cafeteria diet induces metabolic disorders and fecal flora changes in obese rats.

OBJECTIVES: Among diet-induced obesity animal models, the cafeteria diet, which contains human junk food and processed foods, is a popular experimental animal diets in Western countries. Consumption of a cafeteria diet can lead to the development of obesity and non-alcoholic liver disease in as soon as 2 mo, which more accurately reflects human eating patterns. The aim of this study was to establish a Taiwanese cafeteria diet and compare it with a traditional lard-based, 60% high-fat diet in a 12-wk animal model. METHODS: Six-wk-old male Wistar rats were assigned to the following three groups: control diet (C; LabDiet 5001); high-fat diet (HFD; 60% HFD); and the Taiwanese cafeteria diet (CAF). RESULTS: At the end of the study, weight gain and steatosis were observed in the HF and CAF groups. Compared with the HFD group, rats in the CAF group showed significantly higher plasma triacylglycerol concentrations and insulin resistance, which may have been correlated with increased inflammatory responses. Significantly lower hepatic sterol regulatory element-binding protein-1c and insulin receptor substrate-1 protein expressions were observed in the CAF group compared with the HFD group. Additionally, disruption of the microbiotic composition followed by increased obesity-related bacteria was observed in the CAF group. CONCLUSIONS: The present study confirmed that the Taiwanese cafeteria diet-induced rat model provided a potential platform for investigating obesity-related diseases.

[Research Advances in Barrier Technology of Paddy Soil Co-contaminated with As and Cd].

Arsenic (As) and cadmium (Cd) are the most common toxic and harmful heavy metal elements in paddy soils and are easily transferred from the soil to grains. At present, As and Cd and their co-contamination in paddy soils in China are widespread, posing a serious threat to food security and human health. As and Cd have opposite environmental behaviors in soil, and the simultaneous remediation of co-contamination with As and Cd is a current technical difficulty for safe rice production. This review focuses on several practical techniques for simultaneous mitigation of As and Cd uptake and transport in rice in recent years, including water management, passivation, drenching techniques, electrokinetic remediation, phytoremediation, selection of low-accumulation rice varieties, and foliar spraying application. The treatment effects, mechanisms of action, and constraints of various technologies are summarized and analyzed; the development direction of the main barrier control technologies is proposed and the importance of constructing a comprehensive technology model with high regional adaptability is emphasized to provide a reference for the remediation of co-contamination with As and Cd in paddy and safe rice production.

ERRα promotes glycolytic metabolism and targets the NLRP3/caspase-1/GSDMD pathway to regulate pyroptosis in endometrial cancer.

BACKGROUND: Tumor cells can resist chemotherapy-induced pyroptosis through glycolytic reprogramming. Estrogen-related receptor alpha (ERRα) is a central regulator of cellular energy metabolism associated with poor cancer prognosis. Herein, we refine the oncogenic role of ERRα in the pyroptosis pathway and glycolytic metabolism. METHODS: The interaction between ERRα and HIF-1α was verified using co-immunoprecipitation. The transcriptional binding sites of ERRα and NLRP3 were confirmed using dual-luciferase reporter assay and cleavage under targets and tagmentation (CUT&Tag). Flow cytometry, transmission electron microscopy, scanning electron microscopy, cell mito stress test, and extracellular acidification rate analysis were performed to investigate the effects of ERRα on the pyroptosis pathway and glycolytic metabolism. The results of these experiments were further confirmed in endometrial cancer (EC)-derived organoids and nude mice. In addition, the expression of ERRα-related pyroptosis genes was analyzed using The Cancer Genome Atlas and Gene Expression Omnibus database. RESULTS: Triggered by a hypoxic microenvironment, highly expressed ERRα could bind to the promoter of NLRP3 and inhibit caspase-1/GSDMD signaling, which reduced inflammasome activation and increased pyroptosis resistance, thereby resulting in the resistance of cancer cells to cisplatin. Moreover, ERRα activated glycolytic rate-limiting enzyme to bridge glycolytic metabolism and pyroptosis in EC. This phenomenon was further confirmed in EC-derived organoids and nude mice. CUT & Tag sequencing and The Cancer Genome Atlas database analysis showed that ERRα participated in glycolysis and programmed cell death, which resulted in EC progression. CONCLUSIONS: ERRα inhibits pyroptosis in an NLRP3-dependent manner and induces glycolytic metabolism, resulting in cisplatin resistance in EC cells.

Metagenomics reveals taxon-specific responses of soil nitrogen cycling under different fertilization regimes in heavy metal contaminated soil.

Soil deficiency, cyclic erosion, and heavy metal pollution have led to fertility loss and ecological function decline in mining areas. Fertilization is an important way to rapidly replenish soil nutrients, which have a major influence on the soil nitrogen cycling process, but different fertilization regimes have different impacts on soil properties and microbial functional potentials. Here, metagenomic sequencing was used to investigate the different responses of key functional genes of microbial nitrogen cycling to fertilization regimes and explore the potential effects of soil physicochemical properties on the key functional genes. The results indicated that AC-HH (ammonium chloride-high frequency and concentration) treatment significantly increased the gene abundance of norC (13.40-fold), nirK (5.46-fold), and napA (5.37-fold). U-HH (urea-high frequency and concentration) treatment significantly increased the gene abundance of hao (6.24-fold), pmoA-amoA (4.32-fold) norC (7.00-fold), nosZ (3.69-fold), and nirK (6.88-fold). Functional genes were distributed differently among the 10 dominant phyla. The nifH and nifK genes were distributed only in Proteobacteria. The hao gene was distributed in Gemmatimonadetes, Nitrospirae and Proteobacteria. Fertilization regimes caused changes in functional redundancy in soil, and nirK and nirB, which are involved in denitrification, were present in different genera. Fertilization regimes with high frequency and high concentration were more likely to increase the gene abundance at the genus level. In summary, this study provides insights into the taxon-specific response of soil nitrogen cycling under different fertilization regimes, where changes in fertilization regimes affect microbial nitrogen cycling by altering soil physicochemical properties in a complex dynamic environment.

A PDMS-Agar Hybrid Microfluidic Device for the Investigation of Chemical-Mechanical Associative Learning Behavior of C. elegans.

Associative learning is a critical survival trait that promotes behavioral plasticity in response to changing environments. Chemosensation and mechanosensation are important sensory modalities that enable animals to gather information about their internal state and external environment. However, there is a limited amount of research on these two modalities. In this paper, a novel PDMS-agar hybrid microfluidic device is proposed for training and analyzing chemical-mechanical associative learning behavior in the nematode Caenorhabditis elegans. The microfluidic device consisted of a bottom agar gel layer and an upper PDMS layer. A chemical concentration gradient was generated on the agar gel layer, and the PDMS layer served to mimic mechanical stimuli. Based on this platform, C. elegans can perform chemical-mechanical associative learning behavior after training. Our findings indicated that the aversive component of training is the primary driver of the observed associative learning behavior. In addition, the results indicated that the neurotransmitter octopamine is involved in regulating this associative learning behavior via the SER-6 receptor. Thus, the microfluidic device provides a highly efficient platform for studying the associative learning behavior of C. elegans, and it may be applied in mutant screening and drug testing.

Alkalization-induced disintegration increased redox activity of solid humic acids and its soil biogeochemical implications.

Solid humic acids (HAsolid) plays a significant role in maintaining soil ecosystem services, especially in alkaline soil. The unique chemical structures and electrochemical properties are the cores that HAsolid works. In this study, the alkalization-induced variations of particle morphology, functional groups and redox activity of HAsolid were investigated and its soil biogeochemical implications were discussed. Atomic force microscopy (AFM) deflection images and zeta potential results showed that alkalization induced disintegration of HAsolid, with particle size reducing to 200 nm when pH value reached 10.0. This result suggested that HAsolid could exist in alkaline soil. AFM-IR along with fluorescence intensity of HAsolid at different pH further proved that the supramolecular aggregation of HAsolid became loose and dispersive with more redox-active functional groups exposure after alkalization, which could lead to HAsolid susceptible to degradation in alkaline soil. Conductivity of HAsolid decreased 42.86 % when pH increased from 5.0 to 10.0, while electron exchange capacity (EEC) of HAsolid increased 45.30 %, indicating the increase of redox activity of HAsolid. Increase of redox activity of HAsolid by alkalization-induced disintegration not only can accelerate organic pollutant degradation via enhancing microbial co-metabolism, but also speed up the organic carbon loss. This study contributes to a better understanding of the role of HAsolid in organic carbon stocks and fluxes of alkaline soils and has great implications for soil biogeochemical process.

Revealing the Sequence Characteristics and Molecular Mechanisms of ACE Inhibitory Peptides by Comprehensive Characterization of 160,000 Tetrapeptides.

Chronic diseases, such as hypertension, cause great harm to human health. Conventional drugs have promising therapeutic effects, but also cause significant side effects. Food-sourced angiotensin-converting enzyme (ACE) inhibitory peptides are an excellent therapeutic alternative to pharmaceuticals, as they have fewer side effects. However, there is no systematic and effective screening method for ACE inhibitory peptides, and the lack of understanding of the sequence characteristics and molecular mechanism of these inhibitory peptides poses a major obstacle to the development of ACE inhibitory peptides. Through systematically calculating the binding effects of 160,000 tetrapeptides with ACE by molecular docking, we found that peptides with Tyr, Phe, His, Arg, and especially Trp were the characteristic amino acids of ACE inhibitory peptides. The tetrapeptides of WWNW, WRQF, WFRV, YYWK, WWDW, and WWTY rank in the top 10 peptides exhibiting significantly high ACE inhibiting behaviors, with IC50 values between 19.98 ± 8.19 µM and 36.76 ± 1.32 µM. Salt bridges, π-π stacking, π-cations, and hydrogen bonds contributed to the high binding characteristics of the inhibitors and ACE. Introducing eight Trp into rabbit skeletal muscle protein (no Trp in wide sequence) endowed the protein with a more than 90% ACE inhibition rate, further suggesting that meat with a high content of Trp could have potential utility in hypertension regulation. This study provides a clear direction for the development and screening of ACE inhibitory peptides.

Comparative study on plant growth-promoting bacterial inoculation by irrigation and spraying for promoting Bidens pilosa L. phytoremediation of cadmium-contaminated soil.

A field study was conducted to compare FM-1 inoculation by irrigation and spraying for promoting Bidens pilosa L. phytoremediation of cadmium (Cd)-contaminated soil. Cascading relationships between bacterial inoculation by irrigation and spraying and soil properties, plant growth-promoting traits, plant biomass and Cd concentrations in Bidens pilosa L. were explored based on the partial least squares path model (PLS-PM). The results indicated that inoculation with FM-1 not only improved the rhizosphere soil environment of B. pilosa L. but also increased the Cd extracted from the soil. Moreover, Fe and P in leaves play vital roles in promoting plant growth when FM-1 is inoculated by irrigation, while Fe in leaves and stems plays a vital role in promoting plant growth when FM-1 is inoculated by spraying. In addition, FM-1 inoculation decreased the soil pH by affecting soil dehydrogenase and oxalic acid in cases with irrigation and Fe in roots in cases with spraying. Thus, the soil bioavailable Cd content increased and promoted Cd uptake by Bidens pilosa L. To address Cd-induced oxidative stress, Fe in leaves helped to convert GSH into PCs, which played a vital role in ROS scavenging when FM-1 was inoculated by irrigation. The soil urease content effectively increased the POD and APX activities in the leaves of Bidens pilosa L., which helped alleviate Cd-induced oxidative stress when FM-1 was inoculated by spraying. This study compares and illustrates the potential mechanism by which FM-1 inoculation can improve the phytoremediation of Cd-contaminated soil by Bidens pilosa L., suggesting that FM-1 inoculation by irrigation and spraying is useful in the phytoremediation of Cd-contaminated sites.

ERRα Up-Regulates Invadopodia Formation by Targeting HMGCS1 to Promote Endometrial Cancer Invasion and Metastasis.

Estrogen-related receptor alpha (ERRα) plays an important role in endometrial cancer (EC) progression. However, the biological roles of ERRα in EC invasion and metastasis are not clear. This study aimed to investigate the role of ERRα and 3-hydroxy-3-methylglutaryl-CoA synthase 1 (HMGCS1) in regulating intracellular cholesterol metabolism to promote EC progression. ERRα and HMGCS1 interactions were detected by co-immunoprecipitation, and the effects of ERRα/HMGCS1 on the metastasis of EC were investigated by wound-healing and transwell chamber invasion assays. Cellular cholesterol content was measured to verify the relationship between ERRα and cellular cholesterol metabolism. Additionally, immunohistochemistry was performed to confirm that ERRα and HMGCS1 were related to EC progression. Furthermore, the mechanism was investigated using loss-of-function and gain-of-function assays or treatment with simvastatin. High expression levels of ERRα and HMGCS1 promoted intracellular cholesterol metabolism for invadopodia formation. Moreover, inhibiting ERRα and HMGCS1 expression significantly weakened the malignant progression of EC in vitro and in vivo. Our functional analysis showed that ERRα promoted EC invasion and metastasis through the HMGCS1-mediated intracellular cholesterol metabolism pathway, which was dependent on the epithelial-mesenchymal transition pathway. Our findings suggest that ERRα and HMGCS1 are potential targets to suppress EC progression.

Affinity-based alleviation of dissolved organic matter (DOM) on tetracycline toxicity to photosynthesis of green algae Chlorella vulgaris: roles of hydrophilic and hydrophobic DOM.

The environmental fate and toxic effects of antibiotics such as tetracycline (TC) could be influenced by the ubiquitous dissolved organic matter (DOM). However, DOM from different origins has different hydrophilic and hydrophobic properties. It is still unknown the effects of hydrophilic and hydrophobic DOM on the toxic effect of TC. In this study, DOM with hydrophilicity and hydrophobicity was separated and used to investigate their roles in affecting TC toxicity to the photosynthesis of green algae Chlorella vulgaris. Results showed that 10 mg L-1 TC inhibited the efficiency of photosystem II (PSII) of C. vulgaris using light by hindering electron transfer from QA- to QB/QB-, and the O2 release rate of C. vulgaris decreased by a third after 12-h treatment of 10 mg L-1 TC, while both hydrophilic and hydrophobic DOM (20 mg L-1 TOC) alleviated TC toxicity to the photosynthesis of C. vulgaris. In the presence of hydrophilic or hydrophobic DOM, stable complex of TC-hydrophilic DOM or TC-hydrophobic DOM was formed immediately, due to the good affinity of both DOM for TC. Fourier transform infrared spectroscopy result showed that both hydrophilic and hydrophobic DOM could reduce C=O in TC to C-O, and isothermal titration calorimetry result suggested that reactions of both DOM with TC were exothermic (△H < 0) and spontaneous (△G < 0). Thereinto, the reaction constant (Ka) of TC reacting with hydrophobic DOM (Ka=9.70) was higher than that with hydrophilic DOM (Ka=8.93), indicating hydrophobic DOM with more chemical binding sites and accessible fractions for TC. The present study suggests that DOM, especially the hydrophobic DOM, is an important consideration in the environmental impact assessment of antibiotics.

A modified diatomite additive alleviates cadmium-induced oxidative stress in Bidens pilosa L. by altering soil microbial communities.

In the present study, a modified silicon adsorbent (MDSA) was used as a passivator, and we explored the mechanism by which the MDSA helps B. pilosa L. alleviate Cd-induced oxidative stress and its effect on the rhizosphere microbial community. Therefore, a field study was conducted, and MDSA was applied at four levels (control (0 mg m-2), A1 (100 mg m-2), A2 (200 mg m-2), and A3 (400 mg m-2)). The application of MDSA significantly increased the soil pH and decreased the acid-soluble Cd content, which decreased by 30.3% with A3 addition. The addition of MDSA increased the relative abundance of Sordariomycetes due to the increased invertase activity and total nitrogen (TN) and total phosphorus (TP) contents, and the increased soil pH led to increased relative abundances of Alphaproteobacteria and Thermoleophilia. Meanwhile, MDSA addition significantly decreased the Cd concentrations in leaves and stems, which decreased by 19.7 to 39.5% in stems and 24.6 to 43.2% in leaves. All MDSA additions significantly decreased the translocation factor (TF) values of Cd, which decreased by 30.5% (A1), 50.9% (A2), and 52.7% (A3). Moreover, peroxidase (POD) from the antioxidant enzyme system and glutathione (GSH) from the nonenzymatic system played vital roles in scavenging reactive oxygen intermediates (ROIs) such as H2O2 and ⋅O2- in leaves, thereby helping B. pilosa L. alleviate Cd-induced oxidative stress and promote plant growth. Hence, our study indicated that MDSA application improved the rhizosphere soil environment, reconstructed the soil microbial community, helped B. pilosa L. alleviate Cd-induced oxidative stress, and promoted plant growth.

Protective-mechanism-exclusive thermal stability modes of soil organic matter: Novel implication for wildfire effect on soil organic carbon.

Stability of soil organic matter (SOM) is considered to be governed by different protection mechanisms including physical protection (PP), biochemical protection (BCP) and physical plus biochemical protection (PBCP). The thermostability of SOM protected by different mechanisms is unknown, despite its importance for understanding the stability of soil organic carbon (SOC) under frequently occurred wildfires. In this study, we reported for the first time that pyrolysis of SOM under different protection mechanisms in three types of soil (shrub soil, cultivated soil, and meadow soil) followed their own distinct modes regardless of soil type. Specifically, SOM-PP, SOM-PBCP and SOM-BCP from each type of soil were pyrolyzed in the double-step-shape, the mono-step-shape and the linear modes, respectively, when they were heated from room temperature to 800 °C by thermogravimeter. There were more thermolabile organic fractions (pyrolysis temperature < 200 °C) enriched in SOM-PP, while more thermostable organic fractions enriched in SOM-BCP and SOM-PBCP. These findings are of great importance for deeper insight into stability responses of SOM with different occurrence of wildfire.

Depletion of circPDSS1 inhibits ITGA11 production to confer cisplatin sensitivity through miR-515-5p in gastric cancer.

Chemoresistance limits cisplatin (DDP)-mediated treatment for gastric cancer (GC). Circular RNA (circRNA) acts an important role in chemoresistance. However, the underlying mechanism of circPDSS1 regulating DDP sensitivity in GC remains unclear. The expression patterns of circPDSS1, miR-515-5p and integrin subunit alpha 11 (ITGA11) were analyzed by qRT-PCR. Protein expression was checked by Western blotting analysis. Cell viability was investigated by 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell proliferation was evaluated by colony formation assay and 5-ethynyl-2'-deoxyuridine (EdU) assay. The analysis of cell apoptosis, migration and invasion was performed by flow cytometry analysis and transwell assays. Dual-luciferase reporter assay and RNA immunoprecipitation assay were conducted to identify the associations among circPDSS1, miR-515-5p and ITGA11. In vivo assay was implemented using a xenograft mouse model assay. CircPDSS1 and ITGA11 expression were significantly upregulated, whereas miR-515-5p was downregulated in DDP-resistant GC tissues and cells in comparison with controls. CircPDSS1 depletion reduced DDP resistance, cell proliferation, migration and invasion but induced cell apoptosis in DDP-resistant GC cells. CircPDSS1 directly bound to miR-515-5p. CircPDSS1-mediated actions were dependent on the regulation of miR-515-5p. Besides, miR-515-5p was associated with ITGA11, and circPDSS1 regulated ITGA11 expression by binding to miR-515-5p. Overexpression of miR-515-5p improved DDP sensitivity owing to the downregulation of ITGA11. Further, circPDSS1 mediated DDP sensitivity by regulating miR-515-5p and ITGA11 in vivo. CircPDSS1 conferred DDP resistance through the miR-515-5p/ITGA11 axis in GC cells.

Simultaneous mitigation of arsenic and cadmium accumulation in rice grains by foliar inhibitor with ZIF-8@Ge-132.

Simultaneous mitigation of Arsenic (As) and Cadmium (Cd) in rice grains is hardly achieved with conventional soil treatments due to their opposite chemical behaviors in paddy soils. This study evaluates the effectiveness of a novel foliar inhibitor with germanium (Ge) -modified zeolitic imidazolate framework (ZIF-8@Ge-132) in cooperative mitigation of As and Cd in rice grains in a As and Cd co-contaminated paddy field, and the effecting mechanisms are elucidated by a series of advanced techniques. The results showed that the grains inorganic As and Cd was remarkably decreased by 45 % and 66 % by the foliar spay of ZIF-8@Ge-132, respectively. ZIF-8@Ge-132 also reduced the As and Cd contents in rice tissues, except for Cd in leaves, where Cd content increased by 148 %. The image-based measurement of plant phenotypic traits and the elements of image analysis using Laser Ablation-ICP-MS (LA-ICP-MS) and Laser Scanning Confocal Microscopy (LSCM) revealed that the possible mechanisms for the reduction of As and Cd in rice grains were as follows: (i) the thickening of the xylem in roots significantly retarded As and Cd absorption by rice plants. (ii) co-accumulation of Ge and Cd in the leaf vascular system likely contributed to the high Cd retention in rice leaves. (iii) antagonistic effects of Zn suppressed the uptake and transport of As in roots/leaves, resulting a lower As accumulation in rice grains.

Impact of environmental factors on the ammonia-oxidizing and denitrifying microbial community and functional genes along soil profiles from different ecologically degraded areas in the Siding mine.

Ammonia oxidizers (ammonia-oxidizing bacteria (AOB amoA) and ammonia-oxidizing archaea (AOA amoA)) and denitrifiers (encoded by nirS, nirK and nosZ) in the soil nitrogen cycle exist in a variety of natural ecosystems. However, little is known about the contribution of these five N-related functional genes to nitrification and denitrification in the soil profile in severely ecologically degraded areas. Therefore, in the present study, the abundance, diversity and community composition of AOA, AOB, nirS, nirK and nosZ were investigated in the soil profiles of different ecologically degraded areas in the Siding mine. The results indicated that, at the phylum level, the dominant archaea were Crenarchaeota and Thaumarchaeota and the dominant bacteria were Proteobacteria. Heavy metal contents had a great impact on AOA amoA, nirS and nirK gene abundances. AOA amoA contributed more during the ammonia oxidation process and was better adapted for survival in heavy metal-contaminated environments. In addition to heavy metals, the soil organic matter (SOM) content and C/N ratio had strong effects on the AOA and AOB community diversity and structure. In addition, variations in the net ammonification and nitrification rates were proportional to AOA amoA abundance along the soil profile. The soil C/N ratio, soil available phosphorus content and soil moisture influenced the denitrification process. Both soil available phosphorus and moisture were more strongly related to nosZ than to nirS and nirK. In addition, nosZ presented a higher correlation with the nosZ/(nirS + nirK) ratio. Moreover, nosZ/(nirS + nirK) was the key functional gene group that drove the major processes for NH4+-N and NO3--N transformation. This study demonstrated the role and importance of soil property impacts on N-related microbes in the soil profile and provided a better understanding of the role and importance of N-related functional genes and their contribution to soil nitrification and denitrification processes in highly degraded areas in the Siding mine.

Rhombohedral/Cubic In2O3 Phase Junction Hybridized with Polymeric Carbon Nitride for Photodegradation of Organic Pollutants.

In recent studies, phase junctions constructed as photocatalysts have been found to possess great prospects for organic degradation with visible light. In this study, we designed an elaborate rhombohedral corundum/cubic In2O3 phase junction (named MIO) combined with polymeric carbon nitride (PCN) via an in situ calcination method. The performance of the MIO/PCN composites was measured by photodegradation of Rhodamine B under LED light (λ = 420 nm) irradiation. The excellent performance of MIO/PCN could be attributed to the intimate interface contact between MIO and PCN, which provides a reliable charge transmission channel, thereby improving the separation efficiency of charge carriers. Photocatalytic degradation experiments with different quenchers were also executed. The results suggest that the superoxide anion radicals (O2-) and hydroxyl radicals (·OH) played the main roles in the reaction, as opposed to the other scavengers. Moreover, the stability of the MIO/PCN composites was particularly good in the four cycling photocatalytic reactions. This work illustrates that MOF-modified materials have great potential for solving environmental pollution without creating secondary pollution.

Chemical structure and nanomechanics relevant electrochemistry of solid-phase humic acid along a typical forest-river-paddy landscape section in eastern China and its environmental implications.

Solid-phase humic acid (HAsolid) plays a critical role in global carbon cycle and redox biogeochemistry of topsoil, because of its unique physicochemical properties, including electrochemical property. In this study, topsoil HAsolid along a typical forest-river-paddy landscape section in eastern China was investigated in the aspects of electrochemical property, chemical structure and nanomechanics, and their relationship. Nano-size HAsolid particles were extracted from topsoil of paddy soil (PS-HAsolid), forest soil (FS-HAsolid) and riverside sediment (RS-HAsolid). Results showed that all the HAsolid were conductive and played an important role in conductivity of topsoil suspension. HAsolid contained both reversible and irreversible redox peaks, with redox activity of PS-HAsolid > RS-HAsolid > FS-HAsolid. Owing to limited humification, electron exchange capacity (EEC) values of topsoil HAsolid suspensions were modest (3.18-4.45 µmol e-g-1 HAsolid). Compared with RS-HAsolid and FS-HAsolid, PS-HAsolid showed higher aromaticity and higher degree of humification with simple and even nanomechanical property. Long-term cultivation (human activities) as well as high content of polyvalent metals in paddy soil were supposed to facilitate formation of aromatic carbon and improve humification of HAsolid. The results suggested that aromatic carbon and high humification degree of PS-HAsolid contributed to simple and even nanomechanics, which further optimized its electrochemical property. This study not only provides novel insight into the mechanism of HAsolid mediating electron transfer, but also inspires ideas for soil and environmental management with different purposes based on regulation of HAsolid.

Mechanism underlying how a chitosan-based phosphorus adsorbent alleviates cadmium-induced oxidative stress in Bidens pilosa L. and its impact on soil microbial communities: A field study.

In the present study, field experiments were conducted in Side village, Yangshuo, Guilin, Guangxi Province, China, using four C-BPA application levels (control (0 mg m-2), T1 (100 mg m-2), T2 (200 mg m-2) and T3 (400 mg m-2)) to clarify the mechanism by which a chitosan-based phosphorus adsorbent (C-BPA) applied as a passivator helps Bidens pilosa L. (B. pilosa L.) alleviate cadmium (Cd)-induced oxidative stress in Cd-contaminated soil. In the aqueous phase, C-BPA successfully adsorbed Cd2+ on the surface primarily via ion exchange, and C-BPA has potential Cd2+ adsorption capacity, enabling its use as a passivator in real Cd-contaminated environments. In Cd-contaminated soils, under C-BPA application at the T3 level, the pH value increased by 11.2%, and the acid-soluble form of Cd decreased by 26.5%. Additionally, the application of C-BPA improved the rhizosphere soil environment and impacted the soil microbial community diversity and structure. Among soil microbes, the soil fungal community was more sensitive than bacteria to C-BPA application. Dehydrogenase, acetic acid, soil pH and Eurotiomycetes or Dothideomycetes significantly impacted Cd accumulation in the leaves of B. pilosa L.; Cd accumulation in leaves was decreased by 68.1% under C-BPA application at the T3 level. Additionally, the variation of increased catalase (CAT) and peroxidase (POD) jointly promoted plant growth; the plant weight was increased by 112.7% under the C-BPA application at the T3 level. Notably, the production of CAT and POD by B. pilosa L. was more effective than the synthesis of glutathione (GSH) in helping B. pilosa L. eliminate excess reactive oxygen species (ROS). Therefore, our findings demonstrated that the application of C-BPA to Cd-contaminated soil can greatly improve the rhizosphere soil environment, help B. pilosa L. eliminate ROS and promote plant growth.