Neural Circuitries between the Brain and Peripheral Solid Tumors.

The recent discovery of the pivotal role of the central nervous system in controlling tumor initiation and progression has opened a new field of research. Increasing evidence suggests a bidirectional interaction between the brain and tumors. The brain influences the biological behavior of tumor cells through complex neural networks involving the peripheral nervous system, the endocrine system, and the immune system, whereas tumors can establish local autonomic and sensory neural networks to transmit signals into the central nervous system, thereby affecting brain activity. This review aims to summarize the latest research in brain-tumor cross-talk, exploring neural circuitries between the brain and various peripheral solid tumors, analyzing the roles in tumor development and the related molecular mediators and pathologic mechanisms, and highlighting the critical impact on the understanding of cancer biology. Enhanced understanding of reciprocal communication between the brain and tumors will establish a solid theoretical basis for further research and could open avenues for repurposing psychiatric interventions in cancer treatment.

Effects of freeze-thaw leaching on physicochemical properties and cadmium transformation in cadmium contaminated soil.

This study aims to investigate the effect of the combined method of freeze-thaw and leaching on the removal of cadmium (Cd) in soil and to provide a theoretical basis for the remediation of farmland soil polluted by heavy metals. The removal process and mechanism of Cd were deduced through oscillatory leaching experiments and freeze-thaw leaching simulation experiments, and the influence of the freeze-thaw leaching technology on the soil environment was evaluated. The results of oscillatory leaching showed that a mixture consisting of 0.80 mol/L citric acid and 0.80 mol/L ferric chloride in a 1:19 vol ratio effectively remove 47.75 % of Cd, indicating that the composite leaching agent could effectively remove Cd from the soil. The results of the freeze-thaw leaching simulation experiment showed that although the freeze-thaw leaching treatment increased the total Cd content in the 0-5 cm soil layer, the total Cd content in the 5-10 cm, 10-15 cm, and 15-20 cm soil layers decreased by 5.08 %, 2.39 %, and 5.68 %, respectively. The freeze-thaw leaching increased the content of exchangeable Cd (p<0.05), carbonate bound Cd, but decreased organic bound Cd and residual Cd (p<0.05), thereby increasing the bioavailability of Cd. Freeze-thaw leaching not only increased the competitive adsorption of Cd2+ by decreasing soil pH, cation exchange capacity, and increasing the content of exchangeable calcium and exchangeable magnesium, thus reducing the adsorption of Cd in soil. And the results of XPS and FTIR similarly showed that the freeze-thaw leaching could promote the chelation between Cd2+ and hydroxyl, carboxyl and carbonyl functional groups. Although the freeze-thaw leaching destroyed the large particle structure (0.05-2 mm) and large pores in the soil, and increased the clay content (<0.002 mm) and the proportion of small pores in the soil, the XRD results showed that freeze-thaw leaching had no significant effect on the minerals in the soil. In summary, this study shows that freeze-thaw leaching has a significant effect on the removal of soil heavy metals, suggesting that the synergistic effect of freeze-thaw and leaching should be considered in the process of removing soil pollutants in seasonal freeze-thaw zones, and that this method provides a new insight into the remediation of contaminated soils.

Inhibition of microbially mediated total organic carbon decomposition in different types of cadmium contaminated soils with wheat straw addition.

Wheat straw returning is a common agronomic measure in the farmland. Understanding organic carbon transformation is of great significance for carbon budget under the premise of widespread distribution of cadmium (Cd) contaminated soils. An incubation experiment was conducted to assess the influence of Cd contamination on the decomposition and accumulation of total organic carbon (TOC) as well as the composition and abundance of bacterial communities in eight soil types with wheat straw addition. The results showed that inhibition of Cd contamination on microbially mediated organic carbon decomposition was affected by soil types. The lower cumulative C mineralization and higher TOC content could be observed in the acidic soils relative to that in the alkaline soils. The content of Cd in soil exhibits different effects on the inhibition in decomposition of TOC. The high dosage level of Cd had stronger inhibitory impact due to its high toxicity. The decomposition of TOC was restricted by a reduction in soil bacterial abundance and weakening of bacterial activities. Redundancy analysis (RDA) indicated that Proteobacteria and Gemmatimonadetes were abundant in alkaline Cd-contaminated soils with wheat straw addition, while Bacteroidetes dominated cumulative C mineralization in acidic Cd-contamination soils. Moreover, the abundance of predicted functional bacteria indicated that high-dose Cd-contamination and acid environment all inhibited the decomposition of TOC. The present study suggested that pH played an important role on carbon dynamics in the Cd-contaminated soils with wheat straw addition.

Strategies of soil microbial N-cycling in different cadmium contaminated soil with wheat straw return.

Cadmium contamination inevitably affects the microbially mediated transformation of nitrogen in soils with wheat straw return. The responses of nitrogen functional microorganisms to cadmium in acidic and alkaline soils under wheat straw returned are still unclear. In this study, quantitative polymerase chain reaction (qPCR) and sequencing of nitrifying and denitrifying bacteria were performed to investigate the effects of wheat straw application on nitrogen conversion in different Cd-contaminated soils during an incubation experiment. Results showed that the presence of Cd decreased the abundance of hao gene catalyzing nitrification and norB gene catalyzing denitrification process, resulting the accumulation of NH4+-N and reduction of NO3--N in the acidic soils. Additionally, Cd-contamination stimulates the nitrification catalyzed by bacterial amoA gene and thus reduced the NH4+-N content in the alkaline soils. Meanwhile, Cd dominated the decrease of NO3--N content by promoting denitrification process catalyzed by nirS gene. Among all nitrifying and denitrifying microorganisms, Nitrosospira are tolerant to Cd stress under alkaline condition but sensitive to acidic condition, which dominantly harbored hao gene in the acidic soils and bacterial amoA gene in the alkaline soils. This study aimed to provide reasonable information for the rational adoption of wheat straw returning strategies to realize nitrogen regulation in Cd-contaminated farmland soil.

Environment-friendly bio-based controlled-release phosphate fertilizer with waste kitchen oil as coating material: Preparation, characterization, and mechanisms.

Recently, Bio-based polyurethane controlled-release fertilizers (BPCF) have been developed rapidly owing to their environmental friendliness, renewability, and low cost. However, the unsatisfying controlled release prohibits their large-scale direct application in agricultural production. Here, we prepared bio-based controlled-release phosphate (P) fertilizers using harmful waste kitchen oils (WKO) as coating materials. The membrane shell surface was modified with multi-walled carbon nanotubes (CNT), and superhydrophobic controlled-release phosphorus fertilizers (SCRF) were obtained. After CNT modification, the controlled release period of SCRF was greatly improved. Phosphorus released period of SCRF reached over 67 d while that of BPCF was merely ∼49 d. Additionally, the surface energy, cracks, roughness, microstructure, cross-linking degree, etc., of the membrane shells were measured. The results showed that CNT greatly improved the hydrophobic properties of the membrane shells. The findings indicated the application of modified WKO with great agricultural value in preparing environment-friendly BPCFs.

Dynamics of fungal and bacterial communities in different types of soil ageing with different dosages of cadmium.

This study investigated the structure of fungal and bacterial communities in different types of Cd-contaminated soils. The results showed that obvious variations in microbial structure between contaminated alkaline soils and acidic soils. Proteobacteria, Gemmatimonadetes, Bacteroidetes and Basidiomycota dominated the studied communities in the alkaline soils, whereas Actinobacteria, Chloroflexi, Firmicutes, Acidobacteria, Saccharibacteria and Ascomycota were more abundant in the acidic soils. Additionally, Cd tolerant (Proteobacteria, Bacteroidetes, Ascomycota) and sensitive (Actinobacteria, Acidobacteria, Basidiomycota) in alkaline soils and JL-soils, Cd tolerant (Actinobacteria, Acidobacteria, Basidiomycota) and sensitive (Saccharibacteria, Proteobacteria, Bacteroidetes, Ascomycota, Mucoromycota) in the acidic soils were identified. Redundancy analysis and correlation analysis demonstrated that it was significantly affected by different environment parameters in alkaline soils and acidic soils. Varied bacterial community structures in all soils were dominantly influenced by pH and SOM. The similarities among different groups indicated the effect of soil type on microbial community structure was greater than that of Cd level. The above conclusions may provide a new perspective for the bio-remediation of Cd in different types of soils.

Impacts of cadmium addition on the alteration of microbial community and transport of antibiotic resistance genes in oxytetracycline contaminated soil.

The large-scale development in livestock feed industry has increased the chances of antibiotics and heavy metals contamination in the soil. The fate of antibiotic resistance genes (ARGs) and microbial community in heavy metals and antibiotic contaminated soil is still unclear. In this study, we investigated the effect of cadmium (Cd) addition on the transport of ARGs, microbial community and human pathogenic bacteria in oxytetracycline (OTC) contaminated soil. Results showed that the addition of OTC significantly increased the abundance of ARGs and intI1 in the soil and lettuce tissues. The addition of Cd to OTC treated soil further increased the abundance and translocation of ARGs and intI1. Moreover, Cd promoted the transfer of potential human pathogenic bacteria (HPB) into lettuce tissues. Compared with O10 treatment, the addition of Cd decreased the concentration of OTC in soil and lettuce tissue, but slightly increased the fresh weight of lettuce tissues. Redundancy analysis indicated that bacterial community succession is a major factor in ARGs variation. Network analysis indicated that the main host bacteria of ARGs were mainly derived from Proteobacteria. Correlation analysis showed that intI1 was significantly correlated with tetG, tetC, sul1, sul2, ermX, and ermQ. Meanwhile, potential HPB (Clostridium, and Burkholderia) was significantly correlated with intI1 and eight ARGs (tetG, tetC, tetW, tetX, sul1, sul2, ermX, and ermQ.). The findings of this study suggest that the addition of heavy metals to agricultural fields must be considered in order to reduce the transfer of ARGs in the soil and crops.

Compost supplementation with nitrogen loss and greenhouse gas emissions during pig manure composting.

This research investigated the influence of biochar (B) and bean dregs (BD) amendments on carbon and nitrogen losses through greenhouse gas (GHG) emissions during pig manure (PM) composting. The treatments included 15% BD, 10% B and 15% BD+10% B (w/w dry basis of PM) amendments in the compost, whereas the CK (control) lacked any additives. The NH4+-N, C/N and germination index (GI) of the end products ensured compost maturity. Compared with the CK, the 15% BD amendment increased the total nitrogen content (TKN) of the final product by 8.05% but also increased NH3 (54.98%) and GHG emissions (40.35%) as well as nitrogen loss (25.62%). Furthermore, the combined treatment of 15% BD+10% B improved the TKN (2.83%) of the end product and controlled NH3 emissions (33.71%), GHG emissions (29.56%) and nitrogen loss (24.26%) while increasing CO2 only with the 15% BD amendment. Therefore, the combination of BD+B was recommended.

Role of Bentonite on the Mobility of Antibiotic Resistance Genes, and Microbial Community in Oxytetracycline and Cadmium Contaminated Soil.

The effects of bentonite (BT), a commonly used heavy metal deactivator, on the ARGs and microbial communities in soils and lettuce systems contaminated by heavy metals and antibiotics are unclear. A study was conducted to investigate the effect of BT on the mobility of antibiotic resistance genes in oxytetracycline and cadmium contaminated soil. Results showed that the addition of BT reduced the accumulation of OTC and ARGs in the soil and lettuce roots, but increased the abundance of ARGs in lettuce leaves, and increase the risk of human pathogenic bacteria (HPB) transferring to lettuce leaves. Redundancy analysis showed that environmental factors (OTC, H2O, SOM, and pH) were the dominant factors that influence the distribution of ARGs and intI1. Network analysis showed that Proteobacteria and Bacteroidetes were the major host bacteria which caused changes in ARGs and intI1. There were significant positive correlations between ermX and ermQ, and a large number of HPB. The co-occurrence of intl1 with some ARGs (tetC, tetG, ermQ, sul1, and sul2), may threaten human health due to the dispersion of ARGs via horizontal gene transfer.

Impacts of wheat straw addition on dissolved organic matter characteristics in cadmium-contaminated soils: Insights from fluorescence spectroscopy and environmental implications.

Incorporating straw in soil can change the dissolved organic matter (DOM) content and also affect the mobility and solubility of soil pollutants. However, few studies have focused on the spectral features of DOM released by soil after amendment with crop residues. In this study, excitation-emission matrix (EEM) fluorescence and UV-visible absorbance spectroscopy were used to monitor the quality and quantity of the DOM derived from wheat straw incorporation in the soil. We found remarkable changes in the dissolved organic carbon (DOC) concentration (0.10-0.34 g kg-1). But the mean DOC concentrations were lower in the cadmium (Cd2+) added treatments compared with the control treatment due to additional Cd2+. The specific UV-visible absorbance at 254 nm was positively correlated with Cd2+ content, thereby suggesting a strong relationship between aromatic materials and heavy metals. Three fluorescent components were identified by EEM fluorescence combined with parallel factor analysis (PARAFAC) modeling, i.e., UVC humic-like, fulvic acid-like, and tryptophan-like. The relative abundances of these three components and dynamic variations in fluorescent indices predicted the changes in DOM composition during the wheat straws decomposition process. Therefore, the findings obtained in this study can be utilized to evaluate the variations in DOM for soil incorporated with straws in order to support agricultural production and overcome the heavy metal pollution.

Comparison of DGT with traditional methods for assessing cadmium bioavailability to Brassica chinensis in different soils.

There is no universally accepted method for evaluating cadmium (Cd) bioavailability in soil. The diffusive gradient in thin films (DGT) technique is a promising tool, but there is considerable debate about its suitability. The ability of this technique to estimate Cd bioavailability in soils was compared with the abilities of other traditional chemical extraction techniques (soil solution, ethylene diamine tetraacetic acid (EDTA), acetic acid (HAc), calcium chloride (CaCl2), and pseudo-total Cd methods) based on a greenhouse experiment using pakchoi (Brassica chinensis) grown in 15 soils from different provinces of China. In addition, we assessed whether these methods were independent of the soil properties. Correlations between the plant and soil Cd concentrations measured with the traditional extraction techniques were dependent on the pH and organic carbon (OC) content, indicating that these methods are influenced by the soil properties. In contrast, the DGT measurements were independent of the soil properties and showed a higher correlation coefficient compared to that of the traditional techniques. Hence, the DGT technique is better and should be preferable for assessing Cd biological effectiveness in different soil types.

Major factors influencing cadmium uptake from the soil into wheat plants.

At present, soil quality standards for agriculture have not been improved for many years and are applied uniformly for a diverse variety of crops and different soil types, not fully considering the effects of soil properties on cadmium (Cd) uptake via soil-plant transfer. In this study, the characteristics of Cd transfer from soil to eight wheat varieties were investigated, and the results showed that Xiaoyan 22 was moderately sensitive to Cd. Upon growing Xiaoyan 22 in 18 different Chinese soils, we studied the major controlling factors of Cd transfer and constructed a bioaccumulation prediction model from the soil properties. The results showed that pH was the most important factor contributing to Cd uptake. After calibration for the eight wheat varieties, a continuous soil threshold model for wheat was derived for the species sensitive distribution based on food safety standards.